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 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
23 /* Known bugs or deficiencies include:
25 all methods must be provided in header files; can't use a source
26 file that contains only the method templates and "just win". */
30 #include "coretypes.h"
34 #include "pointer-set.h"
38 #include "cp-objcp-common.h"
39 #include "tree-inline.h"
46 #include "tree-iterator.h"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work. */
56 struct pending_template GTY (()) {
57 struct pending_template *next;
58 struct tinst_level *tinst;
61 static GTY(()) struct pending_template *pending_templates;
62 static GTY(()) struct pending_template *last_pending_template;
64 int processing_template_parmlist;
65 static int template_header_count;
67 static GTY(()) tree saved_trees;
68 static VEC(int,heap) *inline_parm_levels;
70 static GTY(()) struct tinst_level *current_tinst_level;
72 static GTY(()) tree saved_access_scope;
74 /* Live only within one (recursive) call to tsubst_expr. We use
75 this to pass the statement expression node from the STMT_EXPR
76 to the EXPR_STMT that is its result. */
77 static tree cur_stmt_expr;
79 /* A map from local variable declarations in the body of the template
80 presently being instantiated to the corresponding instantiated
82 static htab_t local_specializations;
84 /* Contains canonical template parameter types. The vector is indexed by
85 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
86 TREE_LIST, whose TREE_VALUEs contain the canonical template
87 parameters of various types and levels. */
88 static GTY(()) VEC(tree,gc) *canonical_template_parms;
90 #define UNIFY_ALLOW_NONE 0
91 #define UNIFY_ALLOW_MORE_CV_QUAL 1
92 #define UNIFY_ALLOW_LESS_CV_QUAL 2
93 #define UNIFY_ALLOW_DERIVED 4
94 #define UNIFY_ALLOW_INTEGER 8
95 #define UNIFY_ALLOW_OUTER_LEVEL 16
96 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
97 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
99 static void push_access_scope (tree);
100 static void pop_access_scope (tree);
101 static bool resolve_overloaded_unification (tree, tree, tree, tree,
102 unification_kind_t, int);
103 static int try_one_overload (tree, tree, tree, tree, tree,
104 unification_kind_t, int, bool);
105 static int unify (tree, tree, tree, tree, int);
106 static void add_pending_template (tree);
107 static int push_tinst_level (tree);
108 static void pop_tinst_level (void);
109 static tree reopen_tinst_level (struct tinst_level *);
110 static tree tsubst_initializer_list (tree, tree);
111 static tree get_class_bindings (tree, tree, tree);
112 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
114 static void tsubst_enum (tree, tree, tree);
115 static tree add_to_template_args (tree, tree);
116 static tree add_outermost_template_args (tree, tree);
117 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
118 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
120 static int type_unification_real (tree, tree, tree, tree,
121 int, unification_kind_t, int);
122 static void note_template_header (int);
123 static tree convert_nontype_argument_function (tree, tree);
124 static tree convert_nontype_argument (tree, tree);
125 static tree convert_template_argument (tree, tree, tree,
126 tsubst_flags_t, int, tree);
127 static int for_each_template_parm (tree, tree_fn_t, void*,
128 struct pointer_set_t*, bool);
129 static tree expand_template_argument_pack (tree);
130 static tree build_template_parm_index (int, int, int, tree, tree);
131 static bool inline_needs_template_parms (tree);
132 static void push_inline_template_parms_recursive (tree, int);
133 static tree retrieve_local_specialization (tree);
134 static void register_local_specialization (tree, tree);
135 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
136 static int mark_template_parm (tree, void *);
137 static int template_parm_this_level_p (tree, void *);
138 static tree tsubst_friend_function (tree, tree);
139 static tree tsubst_friend_class (tree, tree);
140 static int can_complete_type_without_circularity (tree);
141 static tree get_bindings (tree, tree, tree, bool);
142 static int template_decl_level (tree);
143 static int check_cv_quals_for_unify (int, tree, tree);
144 static void template_parm_level_and_index (tree, int*, int*);
145 static int unify_pack_expansion (tree, tree, tree, tree, int, bool, bool);
146 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
147 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
148 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
149 static void regenerate_decl_from_template (tree, tree);
150 static tree most_specialized_class (tree, tree);
151 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
152 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
153 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
154 static bool check_specialization_scope (void);
155 static tree process_partial_specialization (tree);
156 static void set_current_access_from_decl (tree);
157 static tree get_template_base (tree, tree, tree, tree);
158 static tree try_class_unification (tree, tree, tree, tree);
159 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
161 static bool template_template_parm_bindings_ok_p (tree, tree);
162 static int template_args_equal (tree, tree);
163 static void tsubst_default_arguments (tree);
164 static tree for_each_template_parm_r (tree *, int *, void *);
165 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
166 static void copy_default_args_to_explicit_spec (tree);
167 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
168 static int eq_local_specializations (const void *, const void *);
169 static bool dependent_template_arg_p (tree);
170 static bool any_template_arguments_need_structural_equality_p (tree);
171 static bool dependent_type_p_r (tree);
172 static tree tsubst (tree, tree, tsubst_flags_t, tree);
173 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
174 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
175 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
177 /* Make the current scope suitable for access checking when we are
178 processing T. T can be FUNCTION_DECL for instantiated function
179 template, or VAR_DECL for static member variable (need by
180 instantiate_decl). */
183 push_access_scope (tree t)
185 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
186 || TREE_CODE (t) == VAR_DECL);
188 if (DECL_FRIEND_CONTEXT (t))
189 push_nested_class (DECL_FRIEND_CONTEXT (t));
190 else if (DECL_CLASS_SCOPE_P (t))
191 push_nested_class (DECL_CONTEXT (t));
193 push_to_top_level ();
195 if (TREE_CODE (t) == FUNCTION_DECL)
197 saved_access_scope = tree_cons
198 (NULL_TREE, current_function_decl, saved_access_scope);
199 current_function_decl = t;
203 /* Restore the scope set up by push_access_scope. T is the node we
207 pop_access_scope (tree t)
209 if (TREE_CODE (t) == FUNCTION_DECL)
211 current_function_decl = TREE_VALUE (saved_access_scope);
212 saved_access_scope = TREE_CHAIN (saved_access_scope);
215 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
218 pop_from_top_level ();
221 /* Do any processing required when DECL (a member template
222 declaration) is finished. Returns the TEMPLATE_DECL corresponding
223 to DECL, unless it is a specialization, in which case the DECL
224 itself is returned. */
227 finish_member_template_decl (tree decl)
229 if (decl == error_mark_node)
230 return error_mark_node;
232 gcc_assert (DECL_P (decl));
234 if (TREE_CODE (decl) == TYPE_DECL)
238 type = TREE_TYPE (decl);
239 if (type == error_mark_node)
240 return error_mark_node;
241 if (MAYBE_CLASS_TYPE_P (type)
242 && CLASSTYPE_TEMPLATE_INFO (type)
243 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
245 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
246 check_member_template (tmpl);
251 else if (TREE_CODE (decl) == FIELD_DECL)
252 error ("data member %qD cannot be a member template", decl);
253 else if (DECL_TEMPLATE_INFO (decl))
255 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
257 check_member_template (DECL_TI_TEMPLATE (decl));
258 return DECL_TI_TEMPLATE (decl);
264 error ("invalid member template declaration %qD", decl);
266 return error_mark_node;
269 /* Return the template info node corresponding to T, whatever T is. */
272 get_template_info (tree t)
274 tree tinfo = NULL_TREE;
276 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
277 tinfo = DECL_TEMPLATE_INFO (t);
279 if (!tinfo && TREE_CODE (t) == TYPE_DECL)
282 if (TAGGED_TYPE_P (t))
283 tinfo = TYPE_TEMPLATE_INFO (t);
288 /* Returns the template nesting level of the indicated class TYPE.
298 A<T>::B<U> has depth two, while A<T> has depth one.
299 Both A<T>::B<int> and A<int>::B<U> have depth one, if
300 they are instantiations, not specializations.
302 This function is guaranteed to return 0 if passed NULL_TREE so
303 that, for example, `template_class_depth (current_class_type)' is
307 template_class_depth (tree type)
312 type && TREE_CODE (type) != NAMESPACE_DECL;
313 type = (TREE_CODE (type) == FUNCTION_DECL)
314 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
316 tree tinfo = get_template_info (type);
318 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
319 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
326 /* Subroutine of maybe_begin_member_template_processing.
327 Returns true if processing DECL needs us to push template parms. */
330 inline_needs_template_parms (tree decl)
332 if (! DECL_TEMPLATE_INFO (decl))
335 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
336 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
339 /* Subroutine of maybe_begin_member_template_processing.
340 Push the template parms in PARMS, starting from LEVELS steps into the
341 chain, and ending at the beginning, since template parms are listed
345 push_inline_template_parms_recursive (tree parmlist, int levels)
347 tree parms = TREE_VALUE (parmlist);
351 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
353 ++processing_template_decl;
354 current_template_parms
355 = tree_cons (size_int (processing_template_decl),
356 parms, current_template_parms);
357 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
359 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
361 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
363 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
365 if (parm == error_mark_node)
368 gcc_assert (DECL_P (parm));
370 switch (TREE_CODE (parm))
379 /* Make a CONST_DECL as is done in process_template_parm.
380 It is ugly that we recreate this here; the original
381 version built in process_template_parm is no longer
383 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
385 DECL_ARTIFICIAL (decl) = 1;
386 TREE_CONSTANT (decl) = 1;
387 TREE_READONLY (decl) = 1;
388 DECL_INITIAL (decl) = DECL_INITIAL (parm);
389 SET_DECL_TEMPLATE_PARM_P (decl);
400 /* Restore the template parameter context for a member template or
401 a friend template defined in a class definition. */
404 maybe_begin_member_template_processing (tree decl)
409 if (inline_needs_template_parms (decl))
411 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
412 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
414 if (DECL_TEMPLATE_SPECIALIZATION (decl))
417 parms = TREE_CHAIN (parms);
420 push_inline_template_parms_recursive (parms, levels);
423 /* Remember how many levels of template parameters we pushed so that
424 we can pop them later. */
425 VEC_safe_push (int, heap, inline_parm_levels, levels);
428 /* Undo the effects of maybe_begin_member_template_processing. */
431 maybe_end_member_template_processing (void)
436 if (VEC_length (int, inline_parm_levels) == 0)
439 last = VEC_pop (int, inline_parm_levels);
440 for (i = 0; i < last; ++i)
442 --processing_template_decl;
443 current_template_parms = TREE_CHAIN (current_template_parms);
448 /* Return a new template argument vector which contains all of ARGS,
449 but has as its innermost set of arguments the EXTRA_ARGS. */
452 add_to_template_args (tree args, tree extra_args)
459 extra_depth = TMPL_ARGS_DEPTH (extra_args);
460 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
462 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
463 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
465 for (j = 1; j <= extra_depth; ++j, ++i)
466 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
471 /* Like add_to_template_args, but only the outermost ARGS are added to
472 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
473 (EXTRA_ARGS) levels are added. This function is used to combine
474 the template arguments from a partial instantiation with the
475 template arguments used to attain the full instantiation from the
476 partial instantiation. */
479 add_outermost_template_args (tree args, tree extra_args)
483 /* If there are more levels of EXTRA_ARGS than there are ARGS,
484 something very fishy is going on. */
485 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
487 /* If *all* the new arguments will be the EXTRA_ARGS, just return
489 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
492 /* For the moment, we make ARGS look like it contains fewer levels. */
493 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
495 new_args = add_to_template_args (args, extra_args);
497 /* Now, we restore ARGS to its full dimensions. */
498 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
503 /* Return the N levels of innermost template arguments from the ARGS. */
506 get_innermost_template_args (tree args, int n)
514 /* If N is 1, just return the innermost set of template arguments. */
516 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
518 /* If we're not removing anything, just return the arguments we were
520 extra_levels = TMPL_ARGS_DEPTH (args) - n;
521 gcc_assert (extra_levels >= 0);
522 if (extra_levels == 0)
525 /* Make a new set of arguments, not containing the outer arguments. */
526 new_args = make_tree_vec (n);
527 for (i = 1; i <= n; ++i)
528 SET_TMPL_ARGS_LEVEL (new_args, i,
529 TMPL_ARGS_LEVEL (args, i + extra_levels));
534 /* The inverse of get_innermost_template_args: Return all but the innermost
535 EXTRA_LEVELS levels of template arguments from the ARGS. */
538 strip_innermost_template_args (tree args, int extra_levels)
541 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
546 /* If N is 1, just return the outermost set of template arguments. */
548 return TMPL_ARGS_LEVEL (args, 1);
550 /* If we're not removing anything, just return the arguments we were
552 gcc_assert (extra_levels >= 0);
553 if (extra_levels == 0)
556 /* Make a new set of arguments, not containing the inner arguments. */
557 new_args = make_tree_vec (n);
558 for (i = 1; i <= n; ++i)
559 SET_TMPL_ARGS_LEVEL (new_args, i,
560 TMPL_ARGS_LEVEL (args, i));
565 /* We've got a template header coming up; push to a new level for storing
569 begin_template_parm_list (void)
571 /* We use a non-tag-transparent scope here, which causes pushtag to
572 put tags in this scope, rather than in the enclosing class or
573 namespace scope. This is the right thing, since we want
574 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
575 global template class, push_template_decl handles putting the
576 TEMPLATE_DECL into top-level scope. For a nested template class,
579 template <class T> struct S1 {
580 template <class T> struct S2 {};
583 pushtag contains special code to call pushdecl_with_scope on the
584 TEMPLATE_DECL for S2. */
585 begin_scope (sk_template_parms, NULL);
586 ++processing_template_decl;
587 ++processing_template_parmlist;
588 note_template_header (0);
591 /* This routine is called when a specialization is declared. If it is
592 invalid to declare a specialization here, an error is reported and
593 false is returned, otherwise this routine will return true. */
596 check_specialization_scope (void)
598 tree scope = current_scope ();
602 An explicit specialization shall be declared in the namespace of
603 which the template is a member, or, for member templates, in the
604 namespace of which the enclosing class or enclosing class
605 template is a member. An explicit specialization of a member
606 function, member class or static data member of a class template
607 shall be declared in the namespace of which the class template
609 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
611 error ("explicit specialization in non-namespace scope %qD", scope);
617 In an explicit specialization declaration for a member of a class
618 template or a member template that appears in namespace scope,
619 the member template and some of its enclosing class templates may
620 remain unspecialized, except that the declaration shall not
621 explicitly specialize a class member template if its enclosing
622 class templates are not explicitly specialized as well. */
623 if (current_template_parms)
625 error ("enclosing class templates are not explicitly specialized");
632 /* We've just seen template <>. */
635 begin_specialization (void)
637 begin_scope (sk_template_spec, NULL);
638 note_template_header (1);
639 return check_specialization_scope ();
642 /* Called at then end of processing a declaration preceded by
646 end_specialization (void)
649 reset_specialization ();
652 /* Any template <>'s that we have seen thus far are not referring to a
653 function specialization. */
656 reset_specialization (void)
658 processing_specialization = 0;
659 template_header_count = 0;
662 /* We've just seen a template header. If SPECIALIZATION is nonzero,
663 it was of the form template <>. */
666 note_template_header (int specialization)
668 processing_specialization = specialization;
669 template_header_count++;
672 /* We're beginning an explicit instantiation. */
675 begin_explicit_instantiation (void)
677 gcc_assert (!processing_explicit_instantiation);
678 processing_explicit_instantiation = true;
683 end_explicit_instantiation (void)
685 gcc_assert (processing_explicit_instantiation);
686 processing_explicit_instantiation = false;
689 /* An explicit specialization or partial specialization TMPL is being
690 declared. Check that the namespace in which the specialization is
691 occurring is permissible. Returns false iff it is invalid to
692 specialize TMPL in the current namespace. */
695 check_specialization_namespace (tree tmpl)
697 tree tpl_ns = decl_namespace_context (tmpl);
701 An explicit specialization shall be declared in the namespace of
702 which the template is a member, or, for member templates, in the
703 namespace of which the enclosing class or enclosing class
704 template is a member. An explicit specialization of a member
705 function, member class or static data member of a class template
706 shall be declared in the namespace of which the class template is
708 if (is_associated_namespace (current_namespace, tpl_ns))
709 /* Same or super-using namespace. */
713 permerror (input_location, "specialization of %qD in different namespace", tmpl);
714 permerror (input_location, " from definition of %q+#D", tmpl);
719 /* SPEC is an explicit instantiation. Check that it is valid to
720 perform this explicit instantiation in the current namespace. */
723 check_explicit_instantiation_namespace (tree spec)
727 /* DR 275: An explicit instantiation shall appear in an enclosing
728 namespace of its template. */
729 ns = decl_namespace_context (spec);
730 if (!is_ancestor (current_namespace, ns))
731 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
732 "(which does not enclose namespace %qD)",
733 spec, current_namespace, ns);
736 /* The TYPE is being declared. If it is a template type, that means it
737 is a partial specialization. Do appropriate error-checking. */
740 maybe_process_partial_specialization (tree type)
744 if (type == error_mark_node)
745 return error_mark_node;
747 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
749 error ("name of class shadows template template parameter %qD",
751 return error_mark_node;
754 context = TYPE_CONTEXT (type);
756 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
758 /* This is for ordinary explicit specialization and partial
759 specialization of a template class such as:
761 template <> class C<int>;
765 template <class T> class C<T*>;
767 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
769 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
770 && !COMPLETE_TYPE_P (type))
772 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
773 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
774 if (processing_template_decl)
776 if (push_template_decl (TYPE_MAIN_DECL (type))
778 return error_mark_node;
781 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
782 error ("specialization of %qT after instantiation", type);
784 else if (CLASS_TYPE_P (type)
785 && !CLASSTYPE_USE_TEMPLATE (type)
786 && CLASSTYPE_TEMPLATE_INFO (type)
787 && context && CLASS_TYPE_P (context)
788 && CLASSTYPE_TEMPLATE_INFO (context))
790 /* This is for an explicit specialization of member class
791 template according to [temp.expl.spec/18]:
793 template <> template <class U> class C<int>::D;
795 The context `C<int>' must be an implicit instantiation.
796 Otherwise this is just a member class template declared
799 template <> class C<int> { template <class U> class D; };
800 template <> template <class U> class C<int>::D;
802 In the first case, `C<int>::D' is a specialization of `C<T>::D'
803 while in the second case, `C<int>::D' is a primary template
804 and `C<T>::D' may not exist. */
806 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
807 && !COMPLETE_TYPE_P (type))
811 if (current_namespace
812 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
814 permerror (input_location, "specializing %q#T in different namespace", type);
815 permerror (input_location, " from definition of %q+#D",
816 CLASSTYPE_TI_TEMPLATE (type));
819 /* Check for invalid specialization after instantiation:
821 template <> template <> class C<int>::D<int>;
822 template <> template <class U> class C<int>::D; */
824 for (t = DECL_TEMPLATE_INSTANTIATIONS
825 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
826 t; t = TREE_CHAIN (t))
827 if (TREE_VALUE (t) != type
828 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
829 error ("specialization %qT after instantiation %qT",
830 type, TREE_VALUE (t));
832 /* Mark TYPE as a specialization. And as a result, we only
833 have one level of template argument for the innermost
835 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
836 CLASSTYPE_TI_ARGS (type)
837 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
840 else if (processing_specialization)
842 error ("explicit specialization of non-template %qT", type);
843 return error_mark_node;
849 /* Returns nonzero if we can optimize the retrieval of specializations
850 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
851 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
854 optimize_specialization_lookup_p (tree tmpl)
856 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
857 && DECL_CLASS_SCOPE_P (tmpl)
858 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
860 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
861 /* The optimized lookup depends on the fact that the
862 template arguments for the member function template apply
863 purely to the containing class, which is not true if the
864 containing class is an explicit or partial
866 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
867 && !DECL_MEMBER_TEMPLATE_P (tmpl)
868 && !DECL_CONV_FN_P (tmpl)
869 /* It is possible to have a template that is not a member
870 template and is not a member of a template class:
872 template <typename T>
873 struct S { friend A::f(); };
875 Here, the friend function is a template, but the context does
876 not have template information. The optimized lookup relies
877 on having ARGS be the template arguments for both the class
878 and the function template. */
879 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
882 /* Retrieve the specialization (in the sense of [temp.spec] - a
883 specialization is either an instantiation or an explicit
884 specialization) of TMPL for the given template ARGS. If there is
885 no such specialization, return NULL_TREE. The ARGS are a vector of
886 arguments, or a vector of vectors of arguments, in the case of
887 templates with more than one level of parameters.
889 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
890 then we search for a partial specialization matching ARGS. This
891 parameter is ignored if TMPL is not a class template. */
894 retrieve_specialization (tree tmpl, tree args,
895 bool class_specializations_p)
897 if (args == error_mark_node)
900 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
902 /* There should be as many levels of arguments as there are
903 levels of parameters. */
904 gcc_assert (TMPL_ARGS_DEPTH (args)
905 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
907 if (optimize_specialization_lookup_p (tmpl))
910 tree class_specialization;
911 VEC(tree,gc) *methods;
915 /* The template arguments actually apply to the containing
916 class. Find the class specialization with those
918 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
920 = retrieve_specialization (class_template, args,
921 /*class_specializations_p=*/false);
922 if (!class_specialization)
924 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
925 for the specialization. */
926 idx = class_method_index_for_fn (class_specialization, tmpl);
929 /* Iterate through the methods with the indicated name, looking
930 for the one that has an instance of TMPL. */
931 methods = CLASSTYPE_METHOD_VEC (class_specialization);
932 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
934 tree fn = OVL_CURRENT (fns);
935 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
945 /* Class templates store their instantiations on the
946 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
947 DECL_TEMPLATE_SPECIALIZATIONS list. */
948 if (!class_specializations_p
949 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL
950 && TAGGED_TYPE_P (TREE_TYPE (tmpl)))
951 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
953 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
955 /* Iterate through the list until we find a matching template. */
956 while (*sp != NULL_TREE)
960 if (comp_template_args (TREE_PURPOSE (spec), args))
962 /* Use the move-to-front heuristic to speed up future
966 *sp = TREE_CHAIN (*sp);
967 TREE_CHAIN (spec) = *head;
970 return TREE_VALUE (spec);
972 sp = &TREE_CHAIN (spec);
979 /* Like retrieve_specialization, but for local declarations. */
982 retrieve_local_specialization (tree tmpl)
986 if (local_specializations == NULL)
989 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
990 htab_hash_pointer (tmpl));
991 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
994 /* Returns nonzero iff DECL is a specialization of TMPL. */
997 is_specialization_of (tree decl, tree tmpl)
1001 if (TREE_CODE (decl) == FUNCTION_DECL)
1005 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1011 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1013 for (t = TREE_TYPE (decl);
1015 t = CLASSTYPE_USE_TEMPLATE (t)
1016 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1017 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1024 /* Returns nonzero iff DECL is a specialization of friend declaration
1025 FRIEND_DECL according to [temp.friend]. */
1028 is_specialization_of_friend (tree decl, tree friend_decl)
1030 bool need_template = true;
1033 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1034 || TREE_CODE (decl) == TYPE_DECL);
1036 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1037 of a template class, we want to check if DECL is a specialization
1039 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1040 && DECL_TEMPLATE_INFO (friend_decl)
1041 && !DECL_USE_TEMPLATE (friend_decl))
1043 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1044 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1045 need_template = false;
1047 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1048 && !PRIMARY_TEMPLATE_P (friend_decl))
1049 need_template = false;
1051 /* There is nothing to do if this is not a template friend. */
1052 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1055 if (is_specialization_of (decl, friend_decl))
1059 A member of a class template may be declared to be a friend of a
1060 non-template class. In this case, the corresponding member of
1061 every specialization of the class template is a friend of the
1062 class granting friendship.
1064 For example, given a template friend declaration
1066 template <class T> friend void A<T>::f();
1068 the member function below is considered a friend
1070 template <> struct A<int> {
1074 For this type of template friend, TEMPLATE_DEPTH below will be
1075 nonzero. To determine if DECL is a friend of FRIEND, we first
1076 check if the enclosing class is a specialization of another. */
1078 template_depth = template_class_depth (DECL_CONTEXT (friend_decl));
1080 && DECL_CLASS_SCOPE_P (decl)
1081 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1082 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1084 /* Next, we check the members themselves. In order to handle
1085 a few tricky cases, such as when FRIEND_DECL's are
1087 template <class T> friend void A<T>::g(T t);
1088 template <class T> template <T t> friend void A<T>::h();
1092 void A<int>::g(int);
1093 template <int> void A<int>::h();
1095 we need to figure out ARGS, the template arguments from
1096 the context of DECL. This is required for template substitution
1097 of `T' in the function parameter of `g' and template parameter
1098 of `h' in the above examples. Here ARGS corresponds to `int'. */
1100 tree context = DECL_CONTEXT (decl);
1101 tree args = NULL_TREE;
1102 int current_depth = 0;
1104 while (current_depth < template_depth)
1106 if (CLASSTYPE_TEMPLATE_INFO (context))
1108 if (current_depth == 0)
1109 args = TYPE_TI_ARGS (context);
1111 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1114 context = TYPE_CONTEXT (context);
1117 if (TREE_CODE (decl) == FUNCTION_DECL)
1122 tree friend_args_type;
1123 tree decl_args_type;
1125 /* Make sure that both DECL and FRIEND_DECL are templates or
1127 is_template = DECL_TEMPLATE_INFO (decl)
1128 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1129 if (need_template ^ is_template)
1131 else if (is_template)
1133 /* If both are templates, check template parameter list. */
1135 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1137 if (!comp_template_parms
1138 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1142 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1145 decl_type = TREE_TYPE (decl);
1147 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1148 tf_none, NULL_TREE);
1149 if (friend_type == error_mark_node)
1152 /* Check if return types match. */
1153 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1156 /* Check if function parameter types match, ignoring the
1157 `this' parameter. */
1158 friend_args_type = TYPE_ARG_TYPES (friend_type);
1159 decl_args_type = TYPE_ARG_TYPES (decl_type);
1160 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1161 friend_args_type = TREE_CHAIN (friend_args_type);
1162 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1163 decl_args_type = TREE_CHAIN (decl_args_type);
1165 return compparms (decl_args_type, friend_args_type);
1169 /* DECL is a TYPE_DECL */
1171 tree decl_type = TREE_TYPE (decl);
1173 /* Make sure that both DECL and FRIEND_DECL are templates or
1176 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1177 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1179 if (need_template ^ is_template)
1181 else if (is_template)
1184 /* If both are templates, check the name of the two
1185 TEMPLATE_DECL's first because is_friend didn't. */
1186 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1187 != DECL_NAME (friend_decl))
1190 /* Now check template parameter list. */
1192 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1194 return comp_template_parms
1195 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1199 return (DECL_NAME (decl)
1200 == DECL_NAME (friend_decl));
1206 /* Register the specialization SPEC as a specialization of TMPL with
1207 the indicated ARGS. IS_FRIEND indicates whether the specialization
1208 is actually just a friend declaration. Returns SPEC, or an
1209 equivalent prior declaration, if available. */
1212 register_specialization (tree spec, tree tmpl, tree args, bool is_friend)
1216 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1218 if (TREE_CODE (spec) == FUNCTION_DECL
1219 && uses_template_parms (DECL_TI_ARGS (spec)))
1220 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1221 register it; we want the corresponding TEMPLATE_DECL instead.
1222 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1223 the more obvious `uses_template_parms (spec)' to avoid problems
1224 with default function arguments. In particular, given
1225 something like this:
1227 template <class T> void f(T t1, T t = T())
1229 the default argument expression is not substituted for in an
1230 instantiation unless and until it is actually needed. */
1233 fn = retrieve_specialization (tmpl, args,
1234 /*class_specializations_p=*/false);
1235 /* We can sometimes try to re-register a specialization that we've
1236 already got. In particular, regenerate_decl_from_template calls
1237 duplicate_decls which will update the specialization list. But,
1238 we'll still get called again here anyhow. It's more convenient
1239 to simply allow this than to try to prevent it. */
1242 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1244 if (DECL_TEMPLATE_INSTANTIATION (fn))
1247 || DECL_EXPLICIT_INSTANTIATION (fn))
1249 error ("specialization of %qD after instantiation",
1251 return error_mark_node;
1256 /* This situation should occur only if the first
1257 specialization is an implicit instantiation, the
1258 second is an explicit specialization, and the
1259 implicit instantiation has not yet been used. That
1260 situation can occur if we have implicitly
1261 instantiated a member function and then specialized
1264 We can also wind up here if a friend declaration that
1265 looked like an instantiation turns out to be a
1268 template <class T> void foo(T);
1269 class S { friend void foo<>(int) };
1270 template <> void foo(int);
1272 We transform the existing DECL in place so that any
1273 pointers to it become pointers to the updated
1276 If there was a definition for the template, but not
1277 for the specialization, we want this to look as if
1278 there were no definition, and vice versa. */
1279 DECL_INITIAL (fn) = NULL_TREE;
1280 duplicate_decls (spec, fn, is_friend);
1281 /* The call to duplicate_decls will have applied
1284 An explicit specialization of a function template
1285 is inline only if it is explicitly declared to be,
1286 and independently of whether its function template
1289 to the primary function; now copy the inline bits to
1290 the various clones. */
1291 FOR_EACH_CLONE (clone, fn)
1292 DECL_DECLARED_INLINE_P (clone)
1293 = DECL_DECLARED_INLINE_P (fn);
1294 check_specialization_namespace (fn);
1299 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1301 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1302 /* Dup decl failed, but this is a new definition. Set the
1303 line number so any errors match this new
1305 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1311 /* A specialization must be declared in the same namespace as the
1312 template it is specializing. */
1313 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1314 && !check_specialization_namespace (tmpl))
1315 DECL_CONTEXT (spec) = FROB_CONTEXT (decl_namespace_context (tmpl));
1317 if (!optimize_specialization_lookup_p (tmpl))
1318 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1319 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1324 /* Unregister the specialization SPEC as a specialization of TMPL.
1325 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1326 if the SPEC was listed as a specialization of TMPL. */
1329 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1333 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1335 s = &TREE_CHAIN (*s))
1336 if (TREE_VALUE (*s) == spec)
1339 *s = TREE_CHAIN (*s);
1341 TREE_VALUE (*s) = new_spec;
1348 /* Compare an entry in the local specializations hash table P1 (which
1349 is really a pointer to a TREE_LIST) with P2 (which is really a
1353 eq_local_specializations (const void *p1, const void *p2)
1355 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1358 /* Hash P1, an entry in the local specializations table. */
1361 hash_local_specialization (const void* p1)
1363 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1366 /* Like register_specialization, but for local declarations. We are
1367 registering SPEC, an instantiation of TMPL. */
1370 register_local_specialization (tree spec, tree tmpl)
1374 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1375 htab_hash_pointer (tmpl), INSERT);
1376 *slot = build_tree_list (spec, tmpl);
1379 /* TYPE is a class type. Returns true if TYPE is an explicitly
1380 specialized class. */
1383 explicit_class_specialization_p (tree type)
1385 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1387 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1390 /* Print the list of candidate FNS in an error message. */
1393 print_candidates (tree fns)
1397 const char *str = "candidates are:";
1399 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1403 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1404 error ("%s %+#D", str, OVL_CURRENT (f));
1409 /* Returns the template (one of the functions given by TEMPLATE_ID)
1410 which can be specialized to match the indicated DECL with the
1411 explicit template args given in TEMPLATE_ID. The DECL may be
1412 NULL_TREE if none is available. In that case, the functions in
1413 TEMPLATE_ID are non-members.
1415 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1416 specialization of a member template.
1418 The TEMPLATE_COUNT is the number of references to qualifying
1419 template classes that appeared in the name of the function. See
1420 check_explicit_specialization for a more accurate description.
1422 TSK indicates what kind of template declaration (if any) is being
1423 declared. TSK_TEMPLATE indicates that the declaration given by
1424 DECL, though a FUNCTION_DECL, has template parameters, and is
1425 therefore a template function.
1427 The template args (those explicitly specified and those deduced)
1428 are output in a newly created vector *TARGS_OUT.
1430 If it is impossible to determine the result, an error message is
1431 issued. The error_mark_node is returned to indicate failure. */
1434 determine_specialization (tree template_id,
1437 int need_member_template,
1443 tree explicit_targs;
1444 tree candidates = NULL_TREE;
1445 /* A TREE_LIST of templates of which DECL may be a specialization.
1446 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1447 corresponding TREE_PURPOSE is the set of template arguments that,
1448 when used to instantiate the template, would produce a function
1449 with the signature of DECL. */
1450 tree templates = NULL_TREE;
1452 struct cp_binding_level *b;
1454 *targs_out = NULL_TREE;
1456 if (template_id == error_mark_node || decl == error_mark_node)
1457 return error_mark_node;
1459 fns = TREE_OPERAND (template_id, 0);
1460 explicit_targs = TREE_OPERAND (template_id, 1);
1462 if (fns == error_mark_node)
1463 return error_mark_node;
1465 /* Check for baselinks. */
1466 if (BASELINK_P (fns))
1467 fns = BASELINK_FUNCTIONS (fns);
1469 if (!is_overloaded_fn (fns))
1471 error ("%qD is not a function template", fns);
1472 return error_mark_node;
1475 /* Count the number of template headers specified for this
1478 for (b = current_binding_level;
1479 b->kind == sk_template_parms;
1483 for (; fns; fns = OVL_NEXT (fns))
1485 tree fn = OVL_CURRENT (fns);
1487 if (TREE_CODE (fn) == TEMPLATE_DECL)
1489 tree decl_arg_types;
1492 /* In case of explicit specialization, we need to check if
1493 the number of template headers appearing in the specialization
1494 is correct. This is usually done in check_explicit_specialization,
1495 but the check done there cannot be exhaustive when specializing
1496 member functions. Consider the following code:
1498 template <> void A<int>::f(int);
1499 template <> template <> void A<int>::f(int);
1501 Assuming that A<int> is not itself an explicit specialization
1502 already, the first line specializes "f" which is a non-template
1503 member function, whilst the second line specializes "f" which
1504 is a template member function. So both lines are syntactically
1505 correct, and check_explicit_specialization does not reject
1508 Here, we can do better, as we are matching the specialization
1509 against the declarations. We count the number of template
1510 headers, and we check if they match TEMPLATE_COUNT + 1
1511 (TEMPLATE_COUNT is the number of qualifying template classes,
1512 plus there must be another header for the member template
1515 Notice that if header_count is zero, this is not a
1516 specialization but rather a template instantiation, so there
1517 is no check we can perform here. */
1518 if (header_count && header_count != template_count + 1)
1521 /* Check that the number of template arguments at the
1522 innermost level for DECL is the same as for FN. */
1523 if (current_binding_level->kind == sk_template_parms
1524 && !current_binding_level->explicit_spec_p
1525 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1526 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1527 (current_template_parms))))
1530 /* DECL might be a specialization of FN. */
1531 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1532 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1534 /* For a non-static member function, we need to make sure
1535 that the const qualification is the same. Since
1536 get_bindings does not try to merge the "this" parameter,
1537 we must do the comparison explicitly. */
1538 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1539 && !same_type_p (TREE_VALUE (fn_arg_types),
1540 TREE_VALUE (decl_arg_types)))
1543 /* Skip the "this" parameter and, for constructors of
1544 classes with virtual bases, the VTT parameter. A
1545 full specialization of a constructor will have a VTT
1546 parameter, but a template never will. */
1548 = skip_artificial_parms_for (decl, decl_arg_types);
1550 = skip_artificial_parms_for (fn, fn_arg_types);
1552 /* Check that the number of function parameters matches.
1554 template <class T> void f(int i = 0);
1555 template <> void f<int>();
1556 The specialization f<int> is invalid but is not caught
1557 by get_bindings below. */
1558 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1561 /* Function templates cannot be specializations; there are
1562 no partial specializations of functions. Therefore, if
1563 the type of DECL does not match FN, there is no
1565 if (tsk == tsk_template)
1567 if (compparms (fn_arg_types, decl_arg_types))
1568 candidates = tree_cons (NULL_TREE, fn, candidates);
1572 /* See whether this function might be a specialization of this
1574 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1577 /* We cannot deduce template arguments that when used to
1578 specialize TMPL will produce DECL. */
1581 /* Save this template, and the arguments deduced. */
1582 templates = tree_cons (targs, fn, templates);
1584 else if (need_member_template)
1585 /* FN is an ordinary member function, and we need a
1586 specialization of a member template. */
1588 else if (TREE_CODE (fn) != FUNCTION_DECL)
1589 /* We can get IDENTIFIER_NODEs here in certain erroneous
1592 else if (!DECL_FUNCTION_MEMBER_P (fn))
1593 /* This is just an ordinary non-member function. Nothing can
1594 be a specialization of that. */
1596 else if (DECL_ARTIFICIAL (fn))
1597 /* Cannot specialize functions that are created implicitly. */
1601 tree decl_arg_types;
1603 /* This is an ordinary member function. However, since
1604 we're here, we can assume it's enclosing class is a
1605 template class. For example,
1607 template <typename T> struct S { void f(); };
1608 template <> void S<int>::f() {}
1610 Here, S<int>::f is a non-template, but S<int> is a
1611 template class. If FN has the same type as DECL, we
1612 might be in business. */
1614 if (!DECL_TEMPLATE_INFO (fn))
1615 /* Its enclosing class is an explicit specialization
1616 of a template class. This is not a candidate. */
1619 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1620 TREE_TYPE (TREE_TYPE (fn))))
1621 /* The return types differ. */
1624 /* Adjust the type of DECL in case FN is a static member. */
1625 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1626 if (DECL_STATIC_FUNCTION_P (fn)
1627 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1628 decl_arg_types = TREE_CHAIN (decl_arg_types);
1630 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1633 candidates = tree_cons (NULL_TREE, fn, candidates);
1637 if (templates && TREE_CHAIN (templates))
1643 It is possible for a specialization with a given function
1644 signature to be instantiated from more than one function
1645 template. In such cases, explicit specification of the
1646 template arguments must be used to uniquely identify the
1647 function template specialization being specialized.
1649 Note that here, there's no suggestion that we're supposed to
1650 determine which of the candidate templates is most
1651 specialized. However, we, also have:
1655 Partial ordering of overloaded function template
1656 declarations is used in the following contexts to select
1657 the function template to which a function template
1658 specialization refers:
1660 -- when an explicit specialization refers to a function
1663 So, we do use the partial ordering rules, at least for now.
1664 This extension can only serve to make invalid programs valid,
1665 so it's safe. And, there is strong anecdotal evidence that
1666 the committee intended the partial ordering rules to apply;
1667 the EDG front end has that behavior, and John Spicer claims
1668 that the committee simply forgot to delete the wording in
1669 [temp.expl.spec]. */
1670 tree tmpl = most_specialized_instantiation (templates);
1671 if (tmpl != error_mark_node)
1674 TREE_CHAIN (templates) = NULL_TREE;
1678 if (templates == NULL_TREE && candidates == NULL_TREE)
1680 error ("template-id %qD for %q+D does not match any template "
1681 "declaration", template_id, decl);
1682 return error_mark_node;
1684 else if ((templates && TREE_CHAIN (templates))
1685 || (candidates && TREE_CHAIN (candidates))
1686 || (templates && candidates))
1688 error ("ambiguous template specialization %qD for %q+D",
1690 chainon (candidates, templates);
1691 print_candidates (candidates);
1692 return error_mark_node;
1695 /* We have one, and exactly one, match. */
1698 tree fn = TREE_VALUE (candidates);
1699 /* DECL is a re-declaration of a template function. */
1700 if (TREE_CODE (fn) == TEMPLATE_DECL)
1702 /* It was a specialization of an ordinary member function in a
1704 *targs_out = copy_node (DECL_TI_ARGS (fn));
1705 return DECL_TI_TEMPLATE (fn);
1708 /* It was a specialization of a template. */
1709 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1710 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1712 *targs_out = copy_node (targs);
1713 SET_TMPL_ARGS_LEVEL (*targs_out,
1714 TMPL_ARGS_DEPTH (*targs_out),
1715 TREE_PURPOSE (templates));
1718 *targs_out = TREE_PURPOSE (templates);
1719 return TREE_VALUE (templates);
1722 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1723 but with the default argument values filled in from those in the
1727 copy_default_args_to_explicit_spec_1 (tree spec_types,
1730 tree new_spec_types;
1735 if (spec_types == void_list_node)
1736 return void_list_node;
1738 /* Substitute into the rest of the list. */
1740 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1741 TREE_CHAIN (tmpl_types));
1743 /* Add the default argument for this parameter. */
1744 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1745 TREE_VALUE (spec_types),
1749 /* DECL is an explicit specialization. Replicate default arguments
1750 from the template it specializes. (That way, code like:
1752 template <class T> void f(T = 3);
1753 template <> void f(double);
1756 works, as required.) An alternative approach would be to look up
1757 the correct default arguments at the call-site, but this approach
1758 is consistent with how implicit instantiations are handled. */
1761 copy_default_args_to_explicit_spec (tree decl)
1766 tree new_spec_types;
1770 tree object_type = NULL_TREE;
1771 tree in_charge = NULL_TREE;
1772 tree vtt = NULL_TREE;
1774 /* See if there's anything we need to do. */
1775 tmpl = DECL_TI_TEMPLATE (decl);
1776 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1777 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1778 if (TREE_PURPOSE (t))
1783 old_type = TREE_TYPE (decl);
1784 spec_types = TYPE_ARG_TYPES (old_type);
1786 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1788 /* Remove the this pointer, but remember the object's type for
1790 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1791 spec_types = TREE_CHAIN (spec_types);
1792 tmpl_types = TREE_CHAIN (tmpl_types);
1794 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1796 /* DECL may contain more parameters than TMPL due to the extra
1797 in-charge parameter in constructors and destructors. */
1798 in_charge = spec_types;
1799 spec_types = TREE_CHAIN (spec_types);
1801 if (DECL_HAS_VTT_PARM_P (decl))
1804 spec_types = TREE_CHAIN (spec_types);
1808 /* Compute the merged default arguments. */
1810 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1812 /* Compute the new FUNCTION_TYPE. */
1816 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1821 /* Put the in-charge parameter back. */
1822 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1823 TREE_VALUE (in_charge),
1826 new_type = build_method_type_directly (object_type,
1827 TREE_TYPE (old_type),
1831 new_type = build_function_type (TREE_TYPE (old_type),
1833 new_type = cp_build_type_attribute_variant (new_type,
1834 TYPE_ATTRIBUTES (old_type));
1835 new_type = build_exception_variant (new_type,
1836 TYPE_RAISES_EXCEPTIONS (old_type));
1837 TREE_TYPE (decl) = new_type;
1840 /* Check to see if the function just declared, as indicated in
1841 DECLARATOR, and in DECL, is a specialization of a function
1842 template. We may also discover that the declaration is an explicit
1843 instantiation at this point.
1845 Returns DECL, or an equivalent declaration that should be used
1846 instead if all goes well. Issues an error message if something is
1847 amiss. Returns error_mark_node if the error is not easily
1850 FLAGS is a bitmask consisting of the following flags:
1852 2: The function has a definition.
1853 4: The function is a friend.
1855 The TEMPLATE_COUNT is the number of references to qualifying
1856 template classes that appeared in the name of the function. For
1859 template <class T> struct S { void f(); };
1862 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1863 classes are not counted in the TEMPLATE_COUNT, so that in
1865 template <class T> struct S {};
1866 template <> struct S<int> { void f(); }
1867 template <> void S<int>::f();
1869 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1870 invalid; there should be no template <>.)
1872 If the function is a specialization, it is marked as such via
1873 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1874 is set up correctly, and it is added to the list of specializations
1875 for that template. */
1878 check_explicit_specialization (tree declarator,
1883 int have_def = flags & 2;
1884 int is_friend = flags & 4;
1885 int specialization = 0;
1886 int explicit_instantiation = 0;
1887 int member_specialization = 0;
1888 tree ctype = DECL_CLASS_CONTEXT (decl);
1889 tree dname = DECL_NAME (decl);
1894 if (!processing_specialization)
1897 tsk = tsk_excessive_parms;
1900 tsk = current_tmpl_spec_kind (template_count);
1905 if (processing_specialization)
1908 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1910 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1913 /* This could be something like:
1915 template <class T> void f(T);
1916 class S { friend void f<>(int); } */
1920 /* This case handles bogus declarations like template <>
1921 template <class T> void f<int>(); */
1923 error ("template-id %qD in declaration of primary template",
1930 case tsk_invalid_member_spec:
1931 /* The error has already been reported in
1932 check_specialization_scope. */
1933 return error_mark_node;
1935 case tsk_invalid_expl_inst:
1936 error ("template parameter list used in explicit instantiation");
1942 error ("definition provided for explicit instantiation");
1944 explicit_instantiation = 1;
1947 case tsk_excessive_parms:
1948 case tsk_insufficient_parms:
1949 if (tsk == tsk_excessive_parms)
1950 error ("too many template parameter lists in declaration of %qD",
1952 else if (template_header_count)
1953 error("too few template parameter lists in declaration of %qD", decl);
1955 error("explicit specialization of %qD must be introduced by "
1956 "%<template <>%>", decl);
1960 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1962 member_specialization = 1;
1968 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1970 /* This case handles bogus declarations like template <>
1971 template <class T> void f<int>(); */
1973 if (uses_template_parms (declarator))
1974 error ("function template partial specialization %qD "
1975 "is not allowed", declarator);
1977 error ("template-id %qD in declaration of primary template",
1982 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1983 /* This is a specialization of a member template, without
1984 specialization the containing class. Something like:
1986 template <class T> struct S {
1987 template <class U> void f (U);
1989 template <> template <class U> void S<int>::f(U) {}
1991 That's a specialization -- but of the entire template. */
1999 if (specialization || member_specialization)
2001 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2002 for (; t; t = TREE_CHAIN (t))
2003 if (TREE_PURPOSE (t))
2005 permerror (input_location,
2006 "default argument specified in explicit specialization");
2011 if (specialization || member_specialization || explicit_instantiation)
2013 tree tmpl = NULL_TREE;
2014 tree targs = NULL_TREE;
2016 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2017 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2021 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2026 /* If there is no class context, the explicit instantiation
2027 must be at namespace scope. */
2028 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2030 /* Find the namespace binding, using the declaration
2032 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2034 if (fns == error_mark_node || !is_overloaded_fn (fns))
2036 error ("%qD is not a template function", dname);
2037 fns = error_mark_node;
2041 tree fn = OVL_CURRENT (fns);
2042 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2043 CP_DECL_CONTEXT (fn)))
2044 error ("%qD is not declared in %qD",
2045 decl, current_namespace);
2049 declarator = lookup_template_function (fns, NULL_TREE);
2052 if (declarator == error_mark_node)
2053 return error_mark_node;
2055 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2057 if (!explicit_instantiation)
2058 /* A specialization in class scope. This is invalid,
2059 but the error will already have been flagged by
2060 check_specialization_scope. */
2061 return error_mark_node;
2064 /* It's not valid to write an explicit instantiation in
2067 class C { template void f(); }
2069 This case is caught by the parser. However, on
2072 template class C { void f(); };
2074 (which is invalid) we can get here. The error will be
2081 else if (ctype != NULL_TREE
2082 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2085 /* Find the list of functions in ctype that have the same
2086 name as the declared function. */
2087 tree name = TREE_OPERAND (declarator, 0);
2088 tree fns = NULL_TREE;
2091 if (constructor_name_p (name, ctype))
2093 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2095 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2096 : !CLASSTYPE_DESTRUCTORS (ctype))
2098 /* From [temp.expl.spec]:
2100 If such an explicit specialization for the member
2101 of a class template names an implicitly-declared
2102 special member function (clause _special_), the
2103 program is ill-formed.
2105 Similar language is found in [temp.explicit]. */
2106 error ("specialization of implicitly-declared special member function");
2107 return error_mark_node;
2110 name = is_constructor ? ctor_identifier : dtor_identifier;
2113 if (!DECL_CONV_FN_P (decl))
2115 idx = lookup_fnfields_1 (ctype, name);
2117 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2121 VEC(tree,gc) *methods;
2124 /* For a type-conversion operator, we cannot do a
2125 name-based lookup. We might be looking for `operator
2126 int' which will be a specialization of `operator T'.
2127 So, we find *all* the conversion operators, and then
2128 select from them. */
2131 methods = CLASSTYPE_METHOD_VEC (ctype);
2133 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2134 VEC_iterate (tree, methods, idx, ovl);
2137 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2138 /* There are no more conversion functions. */
2141 /* Glue all these conversion functions together
2142 with those we already have. */
2143 for (; ovl; ovl = OVL_NEXT (ovl))
2144 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2148 if (fns == NULL_TREE)
2150 error ("no member function %qD declared in %qT", name, ctype);
2151 return error_mark_node;
2154 TREE_OPERAND (declarator, 0) = fns;
2157 /* Figure out what exactly is being specialized at this point.
2158 Note that for an explicit instantiation, even one for a
2159 member function, we cannot tell apriori whether the
2160 instantiation is for a member template, or just a member
2161 function of a template class. Even if a member template is
2162 being instantiated, the member template arguments may be
2163 elided if they can be deduced from the rest of the
2165 tmpl = determine_specialization (declarator, decl,
2167 member_specialization,
2171 if (!tmpl || tmpl == error_mark_node)
2172 /* We couldn't figure out what this declaration was
2174 return error_mark_node;
2177 tree gen_tmpl = most_general_template (tmpl);
2179 if (explicit_instantiation)
2181 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2182 is done by do_decl_instantiation later. */
2184 int arg_depth = TMPL_ARGS_DEPTH (targs);
2185 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2187 if (arg_depth > parm_depth)
2189 /* If TMPL is not the most general template (for
2190 example, if TMPL is a friend template that is
2191 injected into namespace scope), then there will
2192 be too many levels of TARGS. Remove some of them
2197 new_targs = make_tree_vec (parm_depth);
2198 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2199 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2200 = TREE_VEC_ELT (targs, i);
2204 return instantiate_template (tmpl, targs, tf_error);
2207 /* If we thought that the DECL was a member function, but it
2208 turns out to be specializing a static member function,
2209 make DECL a static member function as well. */
2210 if (DECL_STATIC_FUNCTION_P (tmpl)
2211 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2212 revert_static_member_fn (decl);
2214 /* If this is a specialization of a member template of a
2215 template class, we want to return the TEMPLATE_DECL, not
2216 the specialization of it. */
2217 if (tsk == tsk_template)
2219 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2220 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2223 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2224 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2225 = DECL_SOURCE_LOCATION (decl);
2226 /* We want to use the argument list specified in the
2227 definition, not in the original declaration. */
2228 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2229 = DECL_ARGUMENTS (decl);
2234 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2235 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2237 /* Inherit default function arguments from the template
2238 DECL is specializing. */
2239 copy_default_args_to_explicit_spec (decl);
2241 /* This specialization has the same protection as the
2242 template it specializes. */
2243 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2244 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2246 /* 7.1.1-1 [dcl.stc]
2248 A storage-class-specifier shall not be specified in an
2249 explicit specialization...
2251 The parser rejects these, so unless action is taken here,
2252 explicit function specializations will always appear with
2255 The action recommended by the C++ CWG in response to C++
2256 defect report 605 is to make the storage class and linkage
2257 of the explicit specialization match the templated function:
2259 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2261 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2263 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2264 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2266 /* This specialization has the same linkage and visibility as
2267 the function template it specializes. */
2268 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2269 if (! TREE_PUBLIC (decl))
2271 DECL_INTERFACE_KNOWN (decl) = 1;
2272 DECL_NOT_REALLY_EXTERN (decl) = 1;
2274 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2275 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2277 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2278 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2282 /* If DECL is a friend declaration, declared using an
2283 unqualified name, the namespace associated with DECL may
2284 have been set incorrectly. For example, in:
2286 template <typename T> void f(T);
2288 struct S { friend void f<int>(int); }
2291 we will have set the DECL_CONTEXT for the friend
2292 declaration to N, rather than to the global namespace. */
2293 if (DECL_NAMESPACE_SCOPE_P (decl))
2294 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2296 if (is_friend && !have_def)
2297 /* This is not really a declaration of a specialization.
2298 It's just the name of an instantiation. But, it's not
2299 a request for an instantiation, either. */
2300 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2301 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2302 /* This is indeed a specialization. In case of constructors
2303 and destructors, we need in-charge and not-in-charge
2304 versions in V3 ABI. */
2305 clone_function_decl (decl, /*update_method_vec_p=*/0);
2307 /* Register this specialization so that we can find it
2309 decl = register_specialization (decl, gen_tmpl, targs, is_friend);
2316 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2317 parameters. These are represented in the same format used for
2318 DECL_TEMPLATE_PARMS. */
2321 comp_template_parms (const_tree parms1, const_tree parms2)
2326 if (parms1 == parms2)
2329 for (p1 = parms1, p2 = parms2;
2330 p1 != NULL_TREE && p2 != NULL_TREE;
2331 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2333 tree t1 = TREE_VALUE (p1);
2334 tree t2 = TREE_VALUE (p2);
2337 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2338 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2340 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2343 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2345 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2346 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2348 /* If either of the template parameters are invalid, assume
2349 they match for the sake of error recovery. */
2350 if (parm1 == error_mark_node || parm2 == error_mark_node)
2353 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2356 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2357 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2358 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2360 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2365 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2366 /* One set of parameters has more parameters lists than the
2373 /* Determine whether PARM is a parameter pack. */
2375 template_parameter_pack_p (const_tree parm)
2377 /* Determine if we have a non-type template parameter pack. */
2378 if (TREE_CODE (parm) == PARM_DECL)
2379 return (DECL_TEMPLATE_PARM_P (parm)
2380 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2382 /* If this is a list of template parameters, we could get a
2383 TYPE_DECL or a TEMPLATE_DECL. */
2384 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2385 parm = TREE_TYPE (parm);
2387 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2388 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2389 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2392 /* Determine whether ARGS describes a variadic template args list,
2393 i.e., one that is terminated by a template argument pack. */
2395 template_args_variadic_p (tree args)
2400 if (args == NULL_TREE)
2403 args = INNERMOST_TEMPLATE_ARGS (args);
2404 nargs = TREE_VEC_LENGTH (args);
2409 last_parm = TREE_VEC_ELT (args, nargs - 1);
2411 return ARGUMENT_PACK_P (last_parm);
2414 /* Generate a new name for the parameter pack name NAME (an
2415 IDENTIFIER_NODE) that incorporates its */
2417 make_ith_pack_parameter_name (tree name, int i)
2419 /* Munge the name to include the parameter index. */
2423 sprintf(numbuf, "%i", i);
2424 newname = (char*)alloca (IDENTIFIER_LENGTH (name) + strlen(numbuf) + 2);
2425 sprintf(newname, "%s#%i", IDENTIFIER_POINTER (name), i);
2426 return get_identifier (newname);
2429 /* Structure used to track the progress of find_parameter_packs_r. */
2430 struct find_parameter_pack_data
2432 /* TREE_LIST that will contain all of the parameter packs found by
2434 tree* parameter_packs;
2436 /* Set of AST nodes that have been visited by the traversal. */
2437 struct pointer_set_t *visited;
2440 /* Identifies all of the argument packs that occur in a template
2441 argument and appends them to the TREE_LIST inside DATA, which is a
2442 find_parameter_pack_data structure. This is a subroutine of
2443 make_pack_expansion and uses_parameter_packs. */
2445 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2448 struct find_parameter_pack_data* ppd =
2449 (struct find_parameter_pack_data*)data;
2450 bool parameter_pack_p = false;
2452 /* Identify whether this is a parameter pack or not. */
2453 switch (TREE_CODE (t))
2455 case TEMPLATE_PARM_INDEX:
2456 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2457 parameter_pack_p = true;
2460 case TEMPLATE_TYPE_PARM:
2461 case TEMPLATE_TEMPLATE_PARM:
2462 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2463 parameter_pack_p = true;
2467 if (FUNCTION_PARAMETER_PACK_P (t))
2469 /* We don't want to walk into the type of a PARM_DECL,
2470 because we don't want to see the type parameter pack. */
2472 parameter_pack_p = true;
2477 /* Not a parameter pack. */
2481 if (parameter_pack_p)
2483 /* Add this parameter pack to the list. */
2484 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2488 cp_walk_tree (&TYPE_CONTEXT (t),
2489 &find_parameter_packs_r, ppd, ppd->visited);
2491 /* This switch statement will return immediately if we don't find a
2493 switch (TREE_CODE (t))
2495 case TEMPLATE_PARM_INDEX:
2498 case BOUND_TEMPLATE_TEMPLATE_PARM:
2499 /* Check the template itself. */
2500 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2501 &find_parameter_packs_r, ppd, ppd->visited);
2502 /* Check the template arguments. */
2503 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2508 case TEMPLATE_TYPE_PARM:
2509 case TEMPLATE_TEMPLATE_PARM:
2516 if (TYPE_PTRMEMFUNC_P (t))
2522 if (TYPE_TEMPLATE_INFO (t))
2523 cp_walk_tree (&TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
2524 &find_parameter_packs_r, ppd, ppd->visited);
2530 cp_walk_tree (&TREE_TYPE (t),
2531 &find_parameter_packs_r, ppd, ppd->visited);
2535 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
2540 case TYPE_PACK_EXPANSION:
2541 case EXPR_PACK_EXPANSION:
2546 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
2551 case IDENTIFIER_NODE:
2552 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
2564 /* Determines if the expression or type T uses any parameter packs. */
2566 uses_parameter_packs (tree t)
2568 tree parameter_packs = NULL_TREE;
2569 struct find_parameter_pack_data ppd;
2570 ppd.parameter_packs = ¶meter_packs;
2571 ppd.visited = pointer_set_create ();
2572 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2573 pointer_set_destroy (ppd.visited);
2574 return parameter_packs != NULL_TREE;
2577 /* Turn ARG, which may be an expression, type, or a TREE_LIST
2578 representation a base-class initializer into a parameter pack
2579 expansion. If all goes well, the resulting node will be an
2580 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
2583 make_pack_expansion (tree arg)
2586 tree parameter_packs = NULL_TREE;
2587 bool for_types = false;
2588 struct find_parameter_pack_data ppd;
2590 if (!arg || arg == error_mark_node)
2593 if (TREE_CODE (arg) == TREE_LIST)
2595 /* The only time we will see a TREE_LIST here is for a base
2596 class initializer. In this case, the TREE_PURPOSE will be a
2597 _TYPE node (representing the base class expansion we're
2598 initializing) and the TREE_VALUE will be a TREE_LIST
2599 containing the initialization arguments.
2601 The resulting expansion looks somewhat different from most
2602 expansions. Rather than returning just one _EXPANSION, we
2603 return a TREE_LIST whose TREE_PURPOSE is a
2604 TYPE_PACK_EXPANSION containing the bases that will be
2605 initialized. The TREE_VALUE will be identical to the
2606 original TREE_VALUE, which is a list of arguments that will
2607 be passed to each base. We do not introduce any new pack
2608 expansion nodes into the TREE_VALUE (although it is possible
2609 that some already exist), because the TREE_PURPOSE and
2610 TREE_VALUE all need to be expanded together with the same
2611 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
2612 resulting TREE_PURPOSE will mention the parameter packs in
2613 both the bases and the arguments to the bases. */
2616 tree parameter_packs = NULL_TREE;
2618 /* Determine which parameter packs will be used by the base
2620 ppd.visited = pointer_set_create ();
2621 ppd.parameter_packs = ¶meter_packs;
2622 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
2625 if (parameter_packs == NULL_TREE)
2627 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
2628 pointer_set_destroy (ppd.visited);
2629 return error_mark_node;
2632 if (TREE_VALUE (arg) != void_type_node)
2634 /* Collect the sets of parameter packs used in each of the
2635 initialization arguments. */
2636 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
2638 /* Determine which parameter packs will be expanded in this
2640 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
2645 pointer_set_destroy (ppd.visited);
2647 /* Create the pack expansion type for the base type. */
2648 purpose = make_node (TYPE_PACK_EXPANSION);
2649 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
2650 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
2652 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2653 they will rarely be compared to anything. */
2654 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
2656 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
2659 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
2662 /* Build the PACK_EXPANSION_* node. */
2663 result = make_node (for_types ? TYPE_PACK_EXPANSION : EXPR_PACK_EXPANSION);
2664 SET_PACK_EXPANSION_PATTERN (result, arg);
2665 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
2667 /* Propagate type and const-expression information. */
2668 TREE_TYPE (result) = TREE_TYPE (arg);
2669 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
2672 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2673 they will rarely be compared to anything. */
2674 SET_TYPE_STRUCTURAL_EQUALITY (result);
2676 /* Determine which parameter packs will be expanded. */
2677 ppd.parameter_packs = ¶meter_packs;
2678 ppd.visited = pointer_set_create ();
2679 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
2680 pointer_set_destroy (ppd.visited);
2682 /* Make sure we found some parameter packs. */
2683 if (parameter_packs == NULL_TREE)
2686 error ("expansion pattern %<%T%> contains no argument packs", arg);
2688 error ("expansion pattern %<%E%> contains no argument packs", arg);
2689 return error_mark_node;
2691 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
2696 /* Checks T for any "bare" parameter packs, which have not yet been
2697 expanded, and issues an error if any are found. This operation can
2698 only be done on full expressions or types (e.g., an expression
2699 statement, "if" condition, etc.), because we could have expressions like:
2701 foo(f(g(h(args)))...)
2703 where "args" is a parameter pack. check_for_bare_parameter_packs
2704 should not be called for the subexpressions args, h(args),
2705 g(h(args)), or f(g(h(args))), because we would produce erroneous
2708 Returns TRUE and emits an error if there were bare parameter packs,
2709 returns FALSE otherwise. */
2711 check_for_bare_parameter_packs (tree t)
2713 tree parameter_packs = NULL_TREE;
2714 struct find_parameter_pack_data ppd;
2716 if (!processing_template_decl || !t || t == error_mark_node)
2719 if (TREE_CODE (t) == TYPE_DECL)
2722 ppd.parameter_packs = ¶meter_packs;
2723 ppd.visited = pointer_set_create ();
2724 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2725 pointer_set_destroy (ppd.visited);
2727 if (parameter_packs)
2729 error ("parameter packs not expanded with %<...%>:");
2730 while (parameter_packs)
2732 tree pack = TREE_VALUE (parameter_packs);
2733 tree name = NULL_TREE;
2735 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
2736 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
2737 name = TYPE_NAME (pack);
2738 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
2739 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
2741 name = DECL_NAME (pack);
2744 inform (input_location, " %qD", name);
2746 inform (input_location, " <anonymous>");
2748 parameter_packs = TREE_CHAIN (parameter_packs);
2757 /* Expand any parameter packs that occur in the template arguments in
2760 expand_template_argument_pack (tree args)
2762 tree result_args = NULL_TREE;
2763 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
2764 int num_result_args = -1;
2766 /* First, determine if we need to expand anything, and the number of
2767 slots we'll need. */
2768 for (in_arg = 0; in_arg < nargs; ++in_arg)
2770 tree arg = TREE_VEC_ELT (args, in_arg);
2771 if (ARGUMENT_PACK_P (arg))
2773 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
2774 if (num_result_args < 0)
2775 num_result_args = in_arg + num_packed;
2777 num_result_args += num_packed;
2781 if (num_result_args >= 0)
2786 /* If no expansion is necessary, we're done. */
2787 if (num_result_args < 0)
2790 /* Expand arguments. */
2791 result_args = make_tree_vec (num_result_args);
2792 for (in_arg = 0; in_arg < nargs; ++in_arg)
2794 tree arg = TREE_VEC_ELT (args, in_arg);
2795 if (ARGUMENT_PACK_P (arg))
2797 tree packed = ARGUMENT_PACK_ARGS (arg);
2798 int i, num_packed = TREE_VEC_LENGTH (packed);
2799 for (i = 0; i < num_packed; ++i, ++out_arg)
2800 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
2804 TREE_VEC_ELT (result_args, out_arg) = arg;
2812 /* Checks if DECL shadows a template parameter.
2814 [temp.local]: A template-parameter shall not be redeclared within its
2815 scope (including nested scopes).
2817 Emits an error and returns TRUE if the DECL shadows a parameter,
2818 returns FALSE otherwise. */
2821 check_template_shadow (tree decl)
2825 /* If we're not in a template, we can't possibly shadow a template
2827 if (!current_template_parms)
2830 /* Figure out what we're shadowing. */
2831 if (TREE_CODE (decl) == OVERLOAD)
2832 decl = OVL_CURRENT (decl);
2833 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2835 /* If there's no previous binding for this name, we're not shadowing
2836 anything, let alone a template parameter. */
2840 /* If we're not shadowing a template parameter, we're done. Note
2841 that OLDDECL might be an OVERLOAD (or perhaps even an
2842 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2844 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2847 /* We check for decl != olddecl to avoid bogus errors for using a
2848 name inside a class. We check TPFI to avoid duplicate errors for
2849 inline member templates. */
2851 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2854 error ("declaration of %q+#D", decl);
2855 error (" shadows template parm %q+#D", olddecl);
2859 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2860 ORIG_LEVEL, DECL, and TYPE. */
2863 build_template_parm_index (int index,
2869 tree t = make_node (TEMPLATE_PARM_INDEX);
2870 TEMPLATE_PARM_IDX (t) = index;
2871 TEMPLATE_PARM_LEVEL (t) = level;
2872 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2873 TEMPLATE_PARM_DECL (t) = decl;
2874 TREE_TYPE (t) = type;
2875 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2876 TREE_READONLY (t) = TREE_READONLY (decl);
2881 /* Find the canonical type parameter for the given template type
2882 parameter. Returns the canonical type parameter, which may be TYPE
2883 if no such parameter existed. */
2885 canonical_type_parameter (tree type)
2888 int idx = TEMPLATE_TYPE_IDX (type);
2889 if (!canonical_template_parms)
2890 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
2892 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
2893 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
2895 list = VEC_index (tree, canonical_template_parms, idx);
2896 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
2897 list = TREE_CHAIN (list);
2900 return TREE_VALUE (list);
2903 VEC_replace(tree, canonical_template_parms, idx,
2904 tree_cons (NULL_TREE, type,
2905 VEC_index (tree, canonical_template_parms, idx)));
2910 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2911 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2912 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2913 new one is created. */
2916 reduce_template_parm_level (tree index, tree type, int levels, tree args,
2917 tsubst_flags_t complain)
2919 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2920 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2921 != TEMPLATE_PARM_LEVEL (index) - levels))
2923 tree orig_decl = TEMPLATE_PARM_DECL (index);
2926 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2927 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2928 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2929 DECL_ARTIFICIAL (decl) = 1;
2930 SET_DECL_TEMPLATE_PARM_P (decl);
2932 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2933 TEMPLATE_PARM_LEVEL (index) - levels,
2934 TEMPLATE_PARM_ORIG_LEVEL (index),
2936 TEMPLATE_PARM_DESCENDANTS (index) = t;
2937 TEMPLATE_PARM_PARAMETER_PACK (t)
2938 = TEMPLATE_PARM_PARAMETER_PACK (index);
2940 /* Template template parameters need this. */
2941 if (TREE_CODE (decl) == TEMPLATE_DECL)
2942 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
2943 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
2947 return TEMPLATE_PARM_DESCENDANTS (index);
2950 /* Process information from new template parameter PARM and append it to the
2951 LIST being built. This new parameter is a non-type parameter iff
2952 IS_NON_TYPE is true. This new parameter is a parameter
2953 pack iff IS_PARAMETER_PACK is true. */
2956 process_template_parm (tree list, tree parm, bool is_non_type,
2957 bool is_parameter_pack)
2964 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2965 defval = TREE_PURPOSE (parm);
2969 tree p = tree_last (list);
2971 if (p && TREE_VALUE (p) != error_mark_node)
2974 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2975 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2977 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2987 parm = TREE_VALUE (parm);
2989 SET_DECL_TEMPLATE_PARM_P (parm);
2991 if (TREE_TYPE (parm) == error_mark_node)
2993 err_parm_list = build_tree_list (defval, parm);
2994 TREE_VALUE (err_parm_list) = error_mark_node;
2995 return chainon (list, err_parm_list);
3001 The top-level cv-qualifiers on the template-parameter are
3002 ignored when determining its type. */
3003 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3004 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3006 err_parm_list = build_tree_list (defval, parm);
3007 TREE_VALUE (err_parm_list) = error_mark_node;
3008 return chainon (list, err_parm_list);
3011 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3013 /* This template parameter is not a parameter pack, but it
3014 should be. Complain about "bare" parameter packs. */
3015 check_for_bare_parameter_packs (TREE_TYPE (parm));
3017 /* Recover by calling this a parameter pack. */
3018 is_parameter_pack = true;
3022 /* A template parameter is not modifiable. */
3023 TREE_CONSTANT (parm) = 1;
3024 TREE_READONLY (parm) = 1;
3025 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3026 TREE_CONSTANT (decl) = 1;
3027 TREE_READONLY (decl) = 1;
3028 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3029 = build_template_parm_index (idx, processing_template_decl,
3030 processing_template_decl,
3031 decl, TREE_TYPE (parm));
3033 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3034 = is_parameter_pack;
3039 parm = TREE_VALUE (TREE_VALUE (parm));
3041 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3043 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3044 /* This is for distinguishing between real templates and template
3045 template parameters */
3046 TREE_TYPE (parm) = t;
3047 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3052 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3053 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3054 decl = build_decl (TYPE_DECL, parm, t);
3057 TYPE_NAME (t) = decl;
3058 TYPE_STUB_DECL (t) = decl;
3060 TEMPLATE_TYPE_PARM_INDEX (t)
3061 = build_template_parm_index (idx, processing_template_decl,
3062 processing_template_decl,
3063 decl, TREE_TYPE (parm));
3064 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3065 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3067 DECL_ARTIFICIAL (decl) = 1;
3068 SET_DECL_TEMPLATE_PARM_P (decl);
3070 parm = build_tree_list (defval, parm);
3071 return chainon (list, parm);
3074 /* The end of a template parameter list has been reached. Process the
3075 tree list into a parameter vector, converting each parameter into a more
3076 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3080 end_template_parm_list (tree parms)
3084 tree saved_parmlist = make_tree_vec (list_length (parms));
3086 current_template_parms
3087 = tree_cons (size_int (processing_template_decl),
3088 saved_parmlist, current_template_parms);
3090 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3092 next = TREE_CHAIN (parm);
3093 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3094 TREE_CHAIN (parm) = NULL_TREE;
3097 --processing_template_parmlist;
3099 return saved_parmlist;
3102 /* end_template_decl is called after a template declaration is seen. */
3105 end_template_decl (void)
3107 reset_specialization ();
3109 if (! processing_template_decl)
3112 /* This matches the pushlevel in begin_template_parm_list. */
3115 --processing_template_decl;
3116 current_template_parms = TREE_CHAIN (current_template_parms);
3119 /* Within the declaration of a template, return all levels of template
3120 parameters that apply. The template parameters are represented as
3121 a TREE_VEC, in the form documented in cp-tree.h for template
3125 current_template_args (void)
3128 tree args = NULL_TREE;
3129 int length = TMPL_PARMS_DEPTH (current_template_parms);
3132 /* If there is only one level of template parameters, we do not
3133 create a TREE_VEC of TREE_VECs. Instead, we return a single
3134 TREE_VEC containing the arguments. */
3136 args = make_tree_vec (length);
3138 for (header = current_template_parms; header; header = TREE_CHAIN (header))
3140 tree a = copy_node (TREE_VALUE (header));
3143 TREE_TYPE (a) = NULL_TREE;
3144 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3146 tree t = TREE_VEC_ELT (a, i);
3148 /* T will be a list if we are called from within a
3149 begin/end_template_parm_list pair, but a vector directly
3150 if within a begin/end_member_template_processing pair. */
3151 if (TREE_CODE (t) == TREE_LIST)
3155 if (!error_operand_p (t))
3157 if (TREE_CODE (t) == TYPE_DECL
3158 || TREE_CODE (t) == TEMPLATE_DECL)
3162 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3164 /* Turn this argument into a TYPE_ARGUMENT_PACK
3165 with a single element, which expands T. */
3166 tree vec = make_tree_vec (1);
3167 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3169 t = make_node (TYPE_ARGUMENT_PACK);
3170 SET_ARGUMENT_PACK_ARGS (t, vec);
3175 t = DECL_INITIAL (t);
3177 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3179 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3180 with a single element, which expands T. */
3181 tree vec = make_tree_vec (1);
3182 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3183 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3185 t = make_node (NONTYPE_ARGUMENT_PACK);
3186 SET_ARGUMENT_PACK_ARGS (t, vec);
3187 TREE_TYPE (t) = type;
3190 TREE_VEC_ELT (a, i) = t;
3196 TREE_VEC_ELT (args, --l) = a;
3204 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3205 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3206 a member template. Used by push_template_decl below. */
3209 build_template_decl (tree decl, tree parms, bool member_template_p)
3211 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3212 DECL_TEMPLATE_PARMS (tmpl) = parms;
3213 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3214 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3215 if (DECL_LANG_SPECIFIC (decl))
3217 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
3218 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
3219 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
3220 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
3221 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
3222 if (DECL_OVERLOADED_OPERATOR_P (decl))
3223 SET_OVERLOADED_OPERATOR_CODE (tmpl,
3224 DECL_OVERLOADED_OPERATOR_P (decl));
3230 struct template_parm_data
3232 /* The level of the template parameters we are currently
3236 /* The index of the specialization argument we are currently
3240 /* An array whose size is the number of template parameters. The
3241 elements are nonzero if the parameter has been used in any one
3242 of the arguments processed so far. */
3245 /* An array whose size is the number of template arguments. The
3246 elements are nonzero if the argument makes use of template
3247 parameters of this level. */
3248 int* arg_uses_template_parms;
3251 /* Subroutine of push_template_decl used to see if each template
3252 parameter in a partial specialization is used in the explicit
3253 argument list. If T is of the LEVEL given in DATA (which is
3254 treated as a template_parm_data*), then DATA->PARMS is marked
3258 mark_template_parm (tree t, void* data)
3262 struct template_parm_data* tpd = (struct template_parm_data*) data;
3264 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3266 level = TEMPLATE_PARM_LEVEL (t);
3267 idx = TEMPLATE_PARM_IDX (t);
3271 level = TEMPLATE_TYPE_LEVEL (t);
3272 idx = TEMPLATE_TYPE_IDX (t);
3275 if (level == tpd->level)
3277 tpd->parms[idx] = 1;
3278 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
3281 /* Return zero so that for_each_template_parm will continue the
3282 traversal of the tree; we want to mark *every* template parm. */
3286 /* Process the partial specialization DECL. */
3289 process_partial_specialization (tree decl)
3291 tree type = TREE_TYPE (decl);
3292 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
3293 tree specargs = CLASSTYPE_TI_ARGS (type);
3294 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
3295 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3296 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
3297 int nargs = TREE_VEC_LENGTH (inner_args);
3298 int ntparms = TREE_VEC_LENGTH (inner_parms);
3300 int did_error_intro = 0;
3301 struct template_parm_data tpd;
3302 struct template_parm_data tpd2;
3304 /* We check that each of the template parameters given in the
3305 partial specialization is used in the argument list to the
3306 specialization. For example:
3308 template <class T> struct S;
3309 template <class T> struct S<T*>;
3311 The second declaration is OK because `T*' uses the template
3312 parameter T, whereas
3314 template <class T> struct S<int>;
3316 is no good. Even trickier is:
3327 The S2<T> declaration is actually invalid; it is a
3328 full-specialization. Of course,
3331 struct S2<T (*)(U)>;
3333 or some such would have been OK. */
3334 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
3335 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
3336 memset (tpd.parms, 0, sizeof (int) * ntparms);
3338 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
3339 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
3340 for (i = 0; i < nargs; ++i)
3342 tpd.current_arg = i;
3343 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
3344 &mark_template_parm,
3347 /*include_nondeduced_p=*/false);
3349 for (i = 0; i < ntparms; ++i)
3350 if (tpd.parms[i] == 0)
3352 /* One of the template parms was not used in the
3354 if (!did_error_intro)
3356 error ("template parameters not used in partial specialization:");
3357 did_error_intro = 1;
3360 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
3363 /* [temp.class.spec]
3365 The argument list of the specialization shall not be identical to
3366 the implicit argument list of the primary template. */
3367 if (comp_template_args
3369 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
3371 error ("partial specialization %qT does not specialize any template arguments", type);
3373 /* [temp.class.spec]
3375 A partially specialized non-type argument expression shall not
3376 involve template parameters of the partial specialization except
3377 when the argument expression is a simple identifier.
3379 The type of a template parameter corresponding to a specialized
3380 non-type argument shall not be dependent on a parameter of the
3383 Also, we verify that pack expansions only occur at the
3384 end of the argument list. */
3385 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
3387 for (i = 0; i < nargs; ++i)
3389 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
3390 tree arg = TREE_VEC_ELT (inner_args, i);
3391 tree packed_args = NULL_TREE;
3394 if (ARGUMENT_PACK_P (arg))
3396 /* Extract the arguments from the argument pack. We'll be
3397 iterating over these in the following loop. */
3398 packed_args = ARGUMENT_PACK_ARGS (arg);
3399 len = TREE_VEC_LENGTH (packed_args);
3402 for (j = 0; j < len; j++)
3405 /* Get the Jth argument in the parameter pack. */
3406 arg = TREE_VEC_ELT (packed_args, j);
3408 if (PACK_EXPANSION_P (arg))
3410 /* Pack expansions must come at the end of the
3412 if ((packed_args && j < len - 1)
3413 || (!packed_args && i < nargs - 1))
3415 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3416 error ("parameter pack argument %qE must be at the end of the template argument list", arg);
3418 error ("parameter pack argument %qT must be at the end of the template argument list", arg);
3421 TREE_VEC_ELT (packed_args, j) = error_mark_node;
3425 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3426 /* We only care about the pattern. */
3427 arg = PACK_EXPANSION_PATTERN (arg);
3429 if (/* These first two lines are the `non-type' bit. */
3431 && TREE_CODE (arg) != TEMPLATE_DECL
3432 /* This next line is the `argument expression is not just a
3433 simple identifier' condition and also the `specialized
3434 non-type argument' bit. */
3435 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
3437 if ((!packed_args && tpd.arg_uses_template_parms[i])
3438 || (packed_args && uses_template_parms (arg)))
3439 error ("template argument %qE involves template parameter(s)",
3443 /* Look at the corresponding template parameter,
3444 marking which template parameters its type depends
3446 tree type = TREE_TYPE (parm);
3450 /* We haven't yet initialized TPD2. Do so now. */
3451 tpd2.arg_uses_template_parms
3452 = (int *) alloca (sizeof (int) * nargs);
3453 /* The number of parameters here is the number in the
3454 main template, which, as checked in the assertion
3456 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
3458 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
3461 /* Mark the template parameters. But this time, we're
3462 looking for the template parameters of the main
3463 template, not in the specialization. */
3464 tpd2.current_arg = i;
3465 tpd2.arg_uses_template_parms[i] = 0;
3466 memset (tpd2.parms, 0, sizeof (int) * nargs);
3467 for_each_template_parm (type,
3468 &mark_template_parm,
3471 /*include_nondeduced_p=*/false);
3473 if (tpd2.arg_uses_template_parms [i])
3475 /* The type depended on some template parameters.
3476 If they are fully specialized in the
3477 specialization, that's OK. */
3479 for (j = 0; j < nargs; ++j)
3480 if (tpd2.parms[j] != 0
3481 && tpd.arg_uses_template_parms [j])
3483 error ("type %qT of template argument %qE depends "
3484 "on template parameter(s)",
3495 if (retrieve_specialization (maintmpl, specargs,
3496 /*class_specializations_p=*/true))
3497 /* We've already got this specialization. */
3500 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
3501 = tree_cons (specargs, inner_parms,
3502 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
3503 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
3507 /* Check that a template declaration's use of default arguments and
3508 parameter packs is not invalid. Here, PARMS are the template
3509 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
3510 a primary template. IS_PARTIAL is nonzero if DECL is a partial
3514 IS_FRIEND_DECL is nonzero if DECL is a friend function template
3515 declaration (but not a definition); 1 indicates a declaration, 2
3516 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
3517 emitted for extraneous default arguments.
3519 Returns TRUE if there were no errors found, FALSE otherwise. */
3522 check_default_tmpl_args (tree decl, tree parms, int is_primary,
3523 int is_partial, int is_friend_decl)
3526 int last_level_to_check;
3528 bool no_errors = true;
3532 A default template-argument shall not be specified in a
3533 function template declaration or a function template definition, nor
3534 in the template-parameter-list of the definition of a member of a
3537 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
3538 /* You can't have a function template declaration in a local
3539 scope, nor you can you define a member of a class template in a
3543 if (current_class_type
3544 && !TYPE_BEING_DEFINED (current_class_type)
3545 && DECL_LANG_SPECIFIC (decl)
3546 /* If this is either a friend defined in the scope of the class
3547 or a member function. */
3548 && (DECL_FUNCTION_MEMBER_P (decl)
3549 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
3550 : DECL_FRIEND_CONTEXT (decl)
3551 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
3553 /* And, if it was a member function, it really was defined in
3554 the scope of the class. */
3555 && (!DECL_FUNCTION_MEMBER_P (decl)
3556 || DECL_INITIALIZED_IN_CLASS_P (decl)))
3557 /* We already checked these parameters when the template was
3558 declared, so there's no need to do it again now. This function
3559 was defined in class scope, but we're processing it's body now
3560 that the class is complete. */
3563 /* Core issue 226 (C++0x only): the following only applies to class
3565 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
3569 If a template-parameter has a default template-argument, all
3570 subsequent template-parameters shall have a default
3571 template-argument supplied. */
3572 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
3574 tree inner_parms = TREE_VALUE (parm_level);
3575 int ntparms = TREE_VEC_LENGTH (inner_parms);
3576 int seen_def_arg_p = 0;
3579 for (i = 0; i < ntparms; ++i)
3581 tree parm = TREE_VEC_ELT (inner_parms, i);
3583 if (parm == error_mark_node)
3586 if (TREE_PURPOSE (parm))
3588 else if (seen_def_arg_p)
3590 error ("no default argument for %qD", TREE_VALUE (parm));
3591 /* For better subsequent error-recovery, we indicate that
3592 there should have been a default argument. */
3593 TREE_PURPOSE (parm) = error_mark_node;
3599 && TREE_CODE (decl) == TYPE_DECL
3601 && template_parameter_pack_p (TREE_VALUE (parm)))
3603 /* A primary class template can only have one
3604 parameter pack, at the end of the template
3607 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
3608 error ("parameter pack %qE must be at the end of the"
3609 " template parameter list", TREE_VALUE (parm));
3611 error ("parameter pack %qT must be at the end of the"
3612 " template parameter list",
3613 TREE_TYPE (TREE_VALUE (parm)));
3615 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
3623 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
3627 /* For an ordinary class template, default template arguments are
3628 allowed at the innermost level, e.g.:
3629 template <class T = int>
3631 but, in a partial specialization, they're not allowed even
3632 there, as we have in [temp.class.spec]:
3634 The template parameter list of a specialization shall not
3635 contain default template argument values.
3637 So, for a partial specialization, or for a function template
3638 (in C++98/C++03), we look at all of them. */
3641 /* But, for a primary class template that is not a partial
3642 specialization we look at all template parameters except the
3644 parms = TREE_CHAIN (parms);
3646 /* Figure out what error message to issue. */
3647 if (is_friend_decl == 2)
3648 msg = "default template arguments may not be used in function template friend re-declaration";
3649 else if (is_friend_decl)
3650 msg = "default template arguments may not be used in function template friend declarations";
3651 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
3652 msg = "default template arguments may not be used in function templates";
3653 else if (is_partial)
3654 msg = "default template arguments may not be used in partial specializations";
3656 msg = "default argument for template parameter for class enclosing %qD";
3658 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
3659 /* If we're inside a class definition, there's no need to
3660 examine the parameters to the class itself. On the one
3661 hand, they will be checked when the class is defined, and,
3662 on the other, default arguments are valid in things like:
3663 template <class T = double>
3664 struct S { template <class U> void f(U); };
3665 Here the default argument for `S' has no bearing on the
3666 declaration of `f'. */
3667 last_level_to_check = template_class_depth (current_class_type) + 1;
3669 /* Check everything. */
3670 last_level_to_check = 0;
3672 for (parm_level = parms;
3673 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
3674 parm_level = TREE_CHAIN (parm_level))
3676 tree inner_parms = TREE_VALUE (parm_level);
3680 ntparms = TREE_VEC_LENGTH (inner_parms);
3681 for (i = 0; i < ntparms; ++i)
3683 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
3686 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
3691 if (is_friend_decl == 2)
3698 /* Clear out the default argument so that we are not
3700 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
3704 /* At this point, if we're still interested in issuing messages,
3705 they must apply to classes surrounding the object declared. */
3707 msg = "default argument for template parameter for class enclosing %qD";
3713 /* Worker for push_template_decl_real, called via
3714 for_each_template_parm. DATA is really an int, indicating the
3715 level of the parameters we are interested in. If T is a template
3716 parameter of that level, return nonzero. */
3719 template_parm_this_level_p (tree t, void* data)
3721 int this_level = *(int *)data;
3724 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3725 level = TEMPLATE_PARM_LEVEL (t);
3727 level = TEMPLATE_TYPE_LEVEL (t);
3728 return level == this_level;
3731 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
3732 parameters given by current_template_args, or reuses a
3733 previously existing one, if appropriate. Returns the DECL, or an
3734 equivalent one, if it is replaced via a call to duplicate_decls.
3736 If IS_FRIEND is true, DECL is a friend declaration. */
3739 push_template_decl_real (tree decl, bool is_friend)
3747 int new_template_p = 0;
3748 /* True if the template is a member template, in the sense of
3750 bool member_template_p = false;
3752 if (decl == error_mark_node)
3755 /* See if this is a partial specialization. */
3756 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
3757 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3758 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
3760 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
3764 /* For a friend, we want the context of the friend function, not
3765 the type of which it is a friend. */
3766 ctx = DECL_CONTEXT (decl);
3767 else if (CP_DECL_CONTEXT (decl)
3768 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
3769 /* In the case of a virtual function, we want the class in which
3771 ctx = CP_DECL_CONTEXT (decl);
3773 /* Otherwise, if we're currently defining some class, the DECL
3774 is assumed to be a member of the class. */
3775 ctx = current_scope ();
3777 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
3780 if (!DECL_CONTEXT (decl))
3781 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
3783 /* See if this is a primary template. */
3784 if (is_friend && ctx)
3785 /* A friend template that specifies a class context, i.e.
3786 template <typename T> friend void A<T>::f();
3790 primary = template_parm_scope_p ();
3794 if (DECL_CLASS_SCOPE_P (decl))
3795 member_template_p = true;
3796 if (TREE_CODE (decl) == TYPE_DECL
3797 && ANON_AGGRNAME_P (DECL_NAME (decl)))
3799 error ("template class without a name");
3800 return error_mark_node;
3802 else if (TREE_CODE (decl) == FUNCTION_DECL)
3804 if (DECL_DESTRUCTOR_P (decl))
3808 A destructor shall not be a member template. */
3809 error ("destructor %qD declared as member template", decl);
3810 return error_mark_node;
3812 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
3813 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
3814 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
3815 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
3816 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
3817 == void_list_node)))
3819 /* [basic.stc.dynamic.allocation]
3821 An allocation function can be a function
3822 template. ... Template allocation functions shall
3823 have two or more parameters. */
3824 error ("invalid template declaration of %qD", decl);
3825 return error_mark_node;
3828 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3829 && CLASS_TYPE_P (TREE_TYPE (decl)))
3833 error ("template declaration of %q#D", decl);
3834 return error_mark_node;
3838 /* Check to see that the rules regarding the use of default
3839 arguments are not being violated. */
3840 check_default_tmpl_args (decl, current_template_parms,
3841 primary, is_partial, /*is_friend_decl=*/0);
3843 /* Ensure that there are no parameter packs in the type of this
3844 declaration that have not been expanded. */
3845 if (TREE_CODE (decl) == FUNCTION_DECL)
3847 /* Check each of the arguments individually to see if there are
3848 any bare parameter packs. */
3849 tree type = TREE_TYPE (decl);
3850 tree arg = DECL_ARGUMENTS (decl);
3851 tree argtype = TYPE_ARG_TYPES (type);
3853 while (arg && argtype)
3855 if (!FUNCTION_PARAMETER_PACK_P (arg)
3856 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
3858 /* This is a PARM_DECL that contains unexpanded parameter
3859 packs. We have already complained about this in the
3860 check_for_bare_parameter_packs call, so just replace
3861 these types with ERROR_MARK_NODE. */
3862 TREE_TYPE (arg) = error_mark_node;
3863 TREE_VALUE (argtype) = error_mark_node;
3866 arg = TREE_CHAIN (arg);
3867 argtype = TREE_CHAIN (argtype);
3870 /* Check for bare parameter packs in the return type and the
3871 exception specifiers. */
3872 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
3873 /* Errors were already issued, set return type to int
3874 as the frontend doesn't expect error_mark_node as
3876 TREE_TYPE (type) = integer_type_node;
3877 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
3878 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
3880 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
3882 TREE_TYPE (decl) = error_mark_node;
3883 return error_mark_node;
3887 return process_partial_specialization (decl);
3889 args = current_template_args ();
3892 || TREE_CODE (ctx) == FUNCTION_DECL
3893 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3894 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3896 if (DECL_LANG_SPECIFIC (decl)
3897 && DECL_TEMPLATE_INFO (decl)
3898 && DECL_TI_TEMPLATE (decl))
3899 tmpl = DECL_TI_TEMPLATE (decl);
3900 /* If DECL is a TYPE_DECL for a class-template, then there won't
3901 be DECL_LANG_SPECIFIC. The information equivalent to
3902 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3903 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3904 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3905 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3907 /* Since a template declaration already existed for this
3908 class-type, we must be redeclaring it here. Make sure
3909 that the redeclaration is valid. */
3910 redeclare_class_template (TREE_TYPE (decl),
3911 current_template_parms);
3912 /* We don't need to create a new TEMPLATE_DECL; just use the
3913 one we already had. */
3914 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3918 tmpl = build_template_decl (decl, current_template_parms,
3922 if (DECL_LANG_SPECIFIC (decl)
3923 && DECL_TEMPLATE_SPECIALIZATION (decl))
3925 /* A specialization of a member template of a template
3927 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3928 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3929 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3935 tree a, t, current, parms;
3937 tree tinfo = get_template_info (decl);
3941 error ("template definition of non-template %q#D", decl);
3942 return error_mark_node;
3945 tmpl = TI_TEMPLATE (tinfo);
3947 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3948 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3949 && DECL_TEMPLATE_SPECIALIZATION (decl)
3950 && DECL_MEMBER_TEMPLATE_P (tmpl))
3954 /* The declaration is a specialization of a member
3955 template, declared outside the class. Therefore, the
3956 innermost template arguments will be NULL, so we
3957 replace them with the arguments determined by the
3958 earlier call to check_explicit_specialization. */
3959 args = DECL_TI_ARGS (decl);
3962 = build_template_decl (decl, current_template_parms,
3964 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3965 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3966 DECL_TI_TEMPLATE (decl) = new_tmpl;
3967 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3968 DECL_TEMPLATE_INFO (new_tmpl)
3969 = tree_cons (tmpl, args, NULL_TREE);
3971 register_specialization (new_tmpl,
3972 most_general_template (tmpl),
3978 /* Make sure the template headers we got make sense. */
3980 parms = DECL_TEMPLATE_PARMS (tmpl);
3981 i = TMPL_PARMS_DEPTH (parms);
3982 if (TMPL_ARGS_DEPTH (args) != i)
3984 error ("expected %d levels of template parms for %q#D, got %d",
3985 i, decl, TMPL_ARGS_DEPTH (args));
3988 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3990 a = TMPL_ARGS_LEVEL (args, i);
3991 t = INNERMOST_TEMPLATE_PARMS (parms);
3993 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3995 if (current == decl)
3996 error ("got %d template parameters for %q#D",
3997 TREE_VEC_LENGTH (a), decl);
3999 error ("got %d template parameters for %q#T",
4000 TREE_VEC_LENGTH (a), current);
4001 error (" but %d required", TREE_VEC_LENGTH (t));
4002 return error_mark_node;
4005 if (current == decl)
4008 current = (TYPE_P (current)
4009 ? TYPE_CONTEXT (current)
4010 : DECL_CONTEXT (current));
4013 /* Check that the parms are used in the appropriate qualifying scopes
4014 in the declarator. */
4015 if (!comp_template_args
4017 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4020 template arguments to %qD do not match original template %qD",
4021 decl, DECL_TEMPLATE_RESULT (tmpl));
4022 if (!uses_template_parms (TI_ARGS (tinfo)))
4023 inform (input_location, "use template<> for an explicit specialization");
4024 /* Avoid crash in import_export_decl. */
4025 DECL_INTERFACE_KNOWN (decl) = 1;
4026 return error_mark_node;
4030 DECL_TEMPLATE_RESULT (tmpl) = decl;
4031 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4033 /* Push template declarations for global functions and types. Note
4034 that we do not try to push a global template friend declared in a
4035 template class; such a thing may well depend on the template
4036 parameters of the class. */
4037 if (new_template_p && !ctx
4038 && !(is_friend && template_class_depth (current_class_type) > 0))
4040 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4041 if (tmpl == error_mark_node)
4042 return error_mark_node;
4044 /* Hide template friend classes that haven't been declared yet. */
4045 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4047 DECL_ANTICIPATED (tmpl) = 1;
4048 DECL_FRIEND_P (tmpl) = 1;
4054 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4057 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4058 if (DECL_CONV_FN_P (tmpl))
4060 int depth = TMPL_PARMS_DEPTH (parms);
4062 /* It is a conversion operator. See if the type converted to
4063 depends on innermost template operands. */
4065 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4067 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4070 /* Give template template parms a DECL_CONTEXT of the template
4071 for which they are a parameter. */
4072 parms = INNERMOST_TEMPLATE_PARMS (parms);
4073 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4075 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4076 if (TREE_CODE (parm) == TEMPLATE_DECL)
4077 DECL_CONTEXT (parm) = tmpl;
4081 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4082 back to its most general template. If TMPL is a specialization,
4083 ARGS may only have the innermost set of arguments. Add the missing
4084 argument levels if necessary. */
4085 if (DECL_TEMPLATE_INFO (tmpl))
4086 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4088 info = tree_cons (tmpl, args, NULL_TREE);
4090 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4091 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4092 else if (DECL_LANG_SPECIFIC (decl))
4093 DECL_TEMPLATE_INFO (decl) = info;
4095 return DECL_TEMPLATE_RESULT (tmpl);
4099 push_template_decl (tree decl)
4101 return push_template_decl_real (decl, false);
4104 /* Called when a class template TYPE is redeclared with the indicated
4105 template PARMS, e.g.:
4107 template <class T> struct S;
4108 template <class T> struct S {}; */
4111 redeclare_class_template (tree type, tree parms)
4117 if (!TYPE_TEMPLATE_INFO (type))
4119 error ("%qT is not a template type", type);
4123 tmpl = TYPE_TI_TEMPLATE (type);
4124 if (!PRIMARY_TEMPLATE_P (tmpl))
4125 /* The type is nested in some template class. Nothing to worry
4126 about here; there are no new template parameters for the nested
4132 error ("template specifiers not specified in declaration of %qD",
4137 parms = INNERMOST_TEMPLATE_PARMS (parms);
4138 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4140 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4142 error ("redeclared with %d template parameter(s)",
4143 TREE_VEC_LENGTH (parms));
4144 inform (input_location, "previous declaration %q+D used %d template parameter(s)",
4145 tmpl, TREE_VEC_LENGTH (tmpl_parms));
4149 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4156 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4157 || TREE_VEC_ELT (parms, i) == error_mark_node)
4160 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4161 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4162 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4163 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4165 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
4167 if (tmpl_parm != error_mark_node
4168 && (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
4169 || (TREE_CODE (tmpl_parm) != TYPE_DECL
4170 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
4171 || (TREE_CODE (tmpl_parm) != PARM_DECL
4172 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
4173 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
4174 || (TREE_CODE (tmpl_parm) == PARM_DECL
4175 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
4176 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))))))
4178 error ("template parameter %q+#D", tmpl_parm);
4179 error ("redeclared here as %q#D", parm);
4183 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
4185 /* We have in [temp.param]:
4187 A template-parameter may not be given default arguments
4188 by two different declarations in the same scope. */
4189 error ("redefinition of default argument for %q#D", parm);
4190 inform (input_location, "%Joriginal definition appeared here", tmpl_parm);
4194 if (parm_default != NULL_TREE)
4195 /* Update the previous template parameters (which are the ones
4196 that will really count) with the new default value. */
4197 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
4198 else if (tmpl_default != NULL_TREE)
4199 /* Update the new parameters, too; they'll be used as the
4200 parameters for any members. */
4201 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
4207 /* Simplify EXPR if it is a non-dependent expression. Returns the
4208 (possibly simplified) expression. */
4211 fold_non_dependent_expr (tree expr)
4213 if (expr == NULL_TREE)
4216 /* If we're in a template, but EXPR isn't value dependent, simplify
4217 it. We're supposed to treat:
4219 template <typename T> void f(T[1 + 1]);
4220 template <typename T> void f(T[2]);
4222 as two declarations of the same function, for example. */
4223 if (processing_template_decl
4224 && !type_dependent_expression_p (expr)
4225 && !value_dependent_expression_p (expr))
4227 HOST_WIDE_INT saved_processing_template_decl;
4229 saved_processing_template_decl = processing_template_decl;
4230 processing_template_decl = 0;
4231 expr = tsubst_copy_and_build (expr,
4234 /*in_decl=*/NULL_TREE,
4235 /*function_p=*/false,
4236 /*integral_constant_expression_p=*/true);
4237 processing_template_decl = saved_processing_template_decl;
4242 /* EXPR is an expression which is used in a constant-expression context.
4243 For instance, it could be a VAR_DECL with a constant initializer.
4244 Extract the innermost constant expression.
4246 This is basically a more powerful version of
4247 integral_constant_value, which can be used also in templates where
4248 initializers can maintain a syntactic rather than semantic form
4249 (even if they are non-dependent, for access-checking purposes). */
4252 fold_decl_constant_value (tree expr)
4254 tree const_expr = expr;
4257 expr = fold_non_dependent_expr (const_expr);
4258 const_expr = integral_constant_value (expr);
4260 while (expr != const_expr);
4265 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
4266 must be a function or a pointer-to-function type, as specified
4267 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
4268 and check that the resulting function has external linkage. */
4271 convert_nontype_argument_function (tree type, tree expr)
4276 fn = instantiate_type (type, fns, tf_none);
4277 if (fn == error_mark_node)
4278 return error_mark_node;
4281 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
4282 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
4283 if (TREE_CODE (fn_no_ptr) == BASELINK)
4284 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
4286 /* [temp.arg.nontype]/1
4288 A template-argument for a non-type, non-template template-parameter
4291 -- the address of an object or function with external linkage. */
4292 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
4294 error ("%qE is not a valid template argument for type %qT "
4295 "because function %qD has not external linkage",
4296 expr, type, fn_no_ptr);
4303 /* Attempt to convert the non-type template parameter EXPR to the
4304 indicated TYPE. If the conversion is successful, return the
4305 converted value. If the conversion is unsuccessful, return
4306 NULL_TREE if we issued an error message, or error_mark_node if we
4307 did not. We issue error messages for out-and-out bad template
4308 parameters, but not simply because the conversion failed, since we
4309 might be just trying to do argument deduction. Both TYPE and EXPR
4310 must be non-dependent.
4312 The conversion follows the special rules described in
4313 [temp.arg.nontype], and it is much more strict than an implicit
4316 This function is called twice for each template argument (see
4317 lookup_template_class for a more accurate description of this
4318 problem). This means that we need to handle expressions which
4319 are not valid in a C++ source, but can be created from the
4320 first call (for instance, casts to perform conversions). These
4321 hacks can go away after we fix the double coercion problem. */
4324 convert_nontype_argument (tree type, tree expr)
4328 /* Detect immediately string literals as invalid non-type argument.
4329 This special-case is not needed for correctness (we would easily
4330 catch this later), but only to provide better diagnostic for this
4331 common user mistake. As suggested by DR 100, we do not mention
4332 linkage issues in the diagnostic as this is not the point. */
4333 if (TREE_CODE (expr) == STRING_CST)
4335 error ("%qE is not a valid template argument for type %qT "
4336 "because string literals can never be used in this context",
4341 /* If we are in a template, EXPR may be non-dependent, but still
4342 have a syntactic, rather than semantic, form. For example, EXPR
4343 might be a SCOPE_REF, rather than the VAR_DECL to which the
4344 SCOPE_REF refers. Preserving the qualifying scope is necessary
4345 so that access checking can be performed when the template is
4346 instantiated -- but here we need the resolved form so that we can
4347 convert the argument. */
4348 expr = fold_non_dependent_expr (expr);
4349 if (error_operand_p (expr))
4350 return error_mark_node;
4351 expr_type = TREE_TYPE (expr);
4353 /* HACK: Due to double coercion, we can get a
4354 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
4355 which is the tree that we built on the first call (see
4356 below when coercing to reference to object or to reference to
4357 function). We just strip everything and get to the arg.
4358 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
4360 if (TREE_CODE (expr) == NOP_EXPR)
4362 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
4364 /* ??? Maybe we could use convert_from_reference here, but we
4365 would need to relax its constraints because the NOP_EXPR
4366 could actually change the type to something more cv-qualified,
4367 and this is not folded by convert_from_reference. */
4368 tree addr = TREE_OPERAND (expr, 0);
4369 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
4370 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
4371 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
4372 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4373 (TREE_TYPE (expr_type),
4374 TREE_TYPE (TREE_TYPE (addr))));
4376 expr = TREE_OPERAND (addr, 0);
4377 expr_type = TREE_TYPE (expr);
4380 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
4381 parameter is a pointer to object, through decay and
4382 qualification conversion. Let's strip everything. */
4383 else if (TYPE_PTROBV_P (type))
4386 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
4387 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
4388 /* Skip the ADDR_EXPR only if it is part of the decay for
4389 an array. Otherwise, it is part of the original argument
4390 in the source code. */
4391 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
4392 expr = TREE_OPERAND (expr, 0);
4393 expr_type = TREE_TYPE (expr);
4397 /* [temp.arg.nontype]/5, bullet 1
4399 For a non-type template-parameter of integral or enumeration type,
4400 integral promotions (_conv.prom_) and integral conversions
4401 (_conv.integral_) are applied. */
4402 if (INTEGRAL_TYPE_P (type))
4404 if (!INTEGRAL_TYPE_P (expr_type))
4405 return error_mark_node;
4407 expr = fold_decl_constant_value (expr);
4408 /* Notice that there are constant expressions like '4 % 0' which
4409 do not fold into integer constants. */
4410 if (TREE_CODE (expr) != INTEGER_CST)
4412 error ("%qE is not a valid template argument for type %qT "
4413 "because it is a non-constant expression", expr, type);
4417 /* At this point, an implicit conversion does what we want,
4418 because we already know that the expression is of integral
4420 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
4421 if (expr == error_mark_node)
4422 return error_mark_node;
4424 /* Conversion was allowed: fold it to a bare integer constant. */
4427 /* [temp.arg.nontype]/5, bullet 2
4429 For a non-type template-parameter of type pointer to object,
4430 qualification conversions (_conv.qual_) and the array-to-pointer
4431 conversion (_conv.array_) are applied. */
4432 else if (TYPE_PTROBV_P (type))
4434 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
4436 A template-argument for a non-type, non-template template-parameter
4437 shall be one of: [...]
4439 -- the name of a non-type template-parameter;
4440 -- the address of an object or function with external linkage, [...]
4441 expressed as "& id-expression" where the & is optional if the name
4442 refers to a function or array, or if the corresponding
4443 template-parameter is a reference.
4445 Here, we do not care about functions, as they are invalid anyway
4446 for a parameter of type pointer-to-object. */
4448 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
4449 /* Non-type template parameters are OK. */
4451 else if (TREE_CODE (expr) != ADDR_EXPR
4452 && TREE_CODE (expr_type) != ARRAY_TYPE)
4454 if (TREE_CODE (expr) == VAR_DECL)
4456 error ("%qD is not a valid template argument "
4457 "because %qD is a variable, not the address of "
4462 /* Other values, like integer constants, might be valid
4463 non-type arguments of some other type. */
4464 return error_mark_node;
4470 decl = ((TREE_CODE (expr) == ADDR_EXPR)
4471 ? TREE_OPERAND (expr, 0) : expr);
4472 if (TREE_CODE (decl) != VAR_DECL)
4474 error ("%qE is not a valid template argument of type %qT "
4475 "because %qE is not a variable",
4479 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
4481 error ("%qE is not a valid template argument of type %qT "
4482 "because %qD does not have external linkage",
4488 expr = decay_conversion (expr);
4489 if (expr == error_mark_node)
4490 return error_mark_node;
4492 expr = perform_qualification_conversions (type, expr);
4493 if (expr == error_mark_node)
4494 return error_mark_node;
4496 /* [temp.arg.nontype]/5, bullet 3
4498 For a non-type template-parameter of type reference to object, no
4499 conversions apply. The type referred to by the reference may be more
4500 cv-qualified than the (otherwise identical) type of the
4501 template-argument. The template-parameter is bound directly to the
4502 template-argument, which must be an lvalue. */
4503 else if (TYPE_REF_OBJ_P (type))
4505 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
4507 return error_mark_node;
4509 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
4511 error ("%qE is not a valid template argument for type %qT "
4512 "because of conflicts in cv-qualification", expr, type);
4516 if (!real_lvalue_p (expr))
4518 error ("%qE is not a valid template argument for type %qT "
4519 "because it is not an lvalue", expr, type);
4523 /* [temp.arg.nontype]/1
4525 A template-argument for a non-type, non-template template-parameter
4526 shall be one of: [...]
4528 -- the address of an object or function with external linkage. */
4529 if (!DECL_EXTERNAL_LINKAGE_P (expr))
4531 error ("%qE is not a valid template argument for type %qT "
4532 "because object %qD has not external linkage",
4537 expr = build_nop (type, build_address (expr));
4539 /* [temp.arg.nontype]/5, bullet 4
4541 For a non-type template-parameter of type pointer to function, only
4542 the function-to-pointer conversion (_conv.func_) is applied. If the
4543 template-argument represents a set of overloaded functions (or a
4544 pointer to such), the matching function is selected from the set
4546 else if (TYPE_PTRFN_P (type))
4548 /* If the argument is a template-id, we might not have enough
4549 context information to decay the pointer. */
4550 if (!type_unknown_p (expr_type))
4552 expr = decay_conversion (expr);
4553 if (expr == error_mark_node)
4554 return error_mark_node;
4557 expr = convert_nontype_argument_function (type, expr);
4558 if (!expr || expr == error_mark_node)
4561 /* [temp.arg.nontype]/5, bullet 5
4563 For a non-type template-parameter of type reference to function, no
4564 conversions apply. If the template-argument represents a set of
4565 overloaded functions, the matching function is selected from the set
4567 else if (TYPE_REFFN_P (type))
4569 if (TREE_CODE (expr) == ADDR_EXPR)
4571 error ("%qE is not a valid template argument for type %qT "
4572 "because it is a pointer", expr, type);
4573 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
4577 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
4578 if (!expr || expr == error_mark_node)
4581 expr = build_nop (type, build_address (expr));
4583 /* [temp.arg.nontype]/5, bullet 6
4585 For a non-type template-parameter of type pointer to member function,
4586 no conversions apply. If the template-argument represents a set of
4587 overloaded member functions, the matching member function is selected
4588 from the set (_over.over_). */
4589 else if (TYPE_PTRMEMFUNC_P (type))
4591 expr = instantiate_type (type, expr, tf_none);
4592 if (expr == error_mark_node)
4593 return error_mark_node;
4595 /* There is no way to disable standard conversions in
4596 resolve_address_of_overloaded_function (called by
4597 instantiate_type). It is possible that the call succeeded by
4598 converting &B::I to &D::I (where B is a base of D), so we need
4599 to reject this conversion here.
4601 Actually, even if there was a way to disable standard conversions,
4602 it would still be better to reject them here so that we can
4603 provide a superior diagnostic. */
4604 if (!same_type_p (TREE_TYPE (expr), type))
4606 /* Make sure we are just one standard conversion off. */
4607 gcc_assert (can_convert (type, TREE_TYPE (expr)));
4608 error ("%qE is not a valid template argument for type %qT "
4609 "because it is of type %qT", expr, type,
4611 inform (input_location, "standard conversions are not allowed in this context");
4615 /* [temp.arg.nontype]/5, bullet 7
4617 For a non-type template-parameter of type pointer to data member,
4618 qualification conversions (_conv.qual_) are applied. */
4619 else if (TYPE_PTRMEM_P (type))
4621 expr = perform_qualification_conversions (type, expr);
4622 if (expr == error_mark_node)
4625 /* A template non-type parameter must be one of the above. */
4629 /* Sanity check: did we actually convert the argument to the
4631 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
4635 /* Subroutine of coerce_template_template_parms, which returns 1 if
4636 PARM_PARM and ARG_PARM match using the rule for the template
4637 parameters of template template parameters. Both PARM and ARG are
4638 template parameters; the rest of the arguments are the same as for
4639 coerce_template_template_parms.
4642 coerce_template_template_parm (tree parm,
4644 tsubst_flags_t complain,
4648 if (arg == NULL_TREE || arg == error_mark_node
4649 || parm == NULL_TREE || parm == error_mark_node)
4652 if (TREE_CODE (arg) != TREE_CODE (parm))
4655 switch (TREE_CODE (parm))
4658 /* We encounter instantiations of templates like
4659 template <template <template <class> class> class TT>
4662 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
4663 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
4665 if (!coerce_template_template_parms
4666 (parmparm, argparm, complain, in_decl, outer_args))
4672 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
4673 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
4674 /* Argument is a parameter pack but parameter is not. */
4679 /* The tsubst call is used to handle cases such as
4681 template <int> class C {};
4682 template <class T, template <T> class TT> class D {};
4685 i.e. the parameter list of TT depends on earlier parameters. */
4686 if (!dependent_type_p (TREE_TYPE (arg))
4688 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
4692 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
4693 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
4694 /* Argument is a parameter pack but parameter is not. */
4707 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
4708 template template parameters. Both PARM_PARMS and ARG_PARMS are
4709 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
4712 Consider the example:
4713 template <class T> class A;
4714 template<template <class U> class TT> class B;
4716 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
4717 the parameters to A, and OUTER_ARGS contains A. */
4720 coerce_template_template_parms (tree parm_parms,
4722 tsubst_flags_t complain,
4726 int nparms, nargs, i;
4730 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
4731 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
4733 nparms = TREE_VEC_LENGTH (parm_parms);
4734 nargs = TREE_VEC_LENGTH (arg_parms);
4736 /* Determine whether we have a parameter pack at the end of the
4737 template template parameter's template parameter list. */
4738 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
4740 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
4742 switch (TREE_CODE (parm))
4746 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
4751 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
4761 && !(variadic_p && nargs >= nparms - 1))
4764 /* Check all of the template parameters except the parameter pack at
4765 the end (if any). */
4766 for (i = 0; i < nparms - variadic_p; ++i)
4768 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
4769 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
4772 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
4773 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
4775 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
4783 /* Check each of the template parameters in the template
4784 argument against the template parameter pack at the end of
4785 the template template parameter. */
4786 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
4789 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
4791 for (; i < nargs; ++i)
4793 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
4796 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
4798 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
4807 /* Verifies that the deduced template arguments (in TARGS) for the
4808 template template parameters (in TPARMS) represent valid bindings,
4809 by comparing the template parameter list of each template argument
4810 to the template parameter list of its corresponding template
4811 template parameter, in accordance with DR150. This
4812 routine can only be called after all template arguments have been
4813 deduced. It will return TRUE if all of the template template
4814 parameter bindings are okay, FALSE otherwise. */
4816 template_template_parm_bindings_ok_p (tree tparms, tree targs)
4818 int i, ntparms = TREE_VEC_LENGTH (tparms);
4821 /* We're dealing with template parms in this process. */
4822 ++processing_template_decl;
4824 targs = INNERMOST_TEMPLATE_ARGS (targs);
4826 for (i = 0; i < ntparms; ++i)
4828 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
4829 tree targ = TREE_VEC_ELT (targs, i);
4831 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
4833 tree packed_args = NULL_TREE;
4836 if (ARGUMENT_PACK_P (targ))
4838 /* Look inside the argument pack. */
4839 packed_args = ARGUMENT_PACK_ARGS (targ);
4840 len = TREE_VEC_LENGTH (packed_args);
4843 for (idx = 0; idx < len; ++idx)
4845 tree targ_parms = NULL_TREE;
4848 /* Extract the next argument from the argument
4850 targ = TREE_VEC_ELT (packed_args, idx);
4852 if (PACK_EXPANSION_P (targ))
4853 /* Look at the pattern of the pack expansion. */
4854 targ = PACK_EXPANSION_PATTERN (targ);
4856 /* Extract the template parameters from the template
4858 if (TREE_CODE (targ) == TEMPLATE_DECL)
4859 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
4860 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
4861 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
4863 /* Verify that we can coerce the template template
4864 parameters from the template argument to the template
4865 parameter. This requires an exact match. */
4867 && !coerce_template_template_parms
4868 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
4883 --processing_template_decl;
4887 /* Convert the indicated template ARG as necessary to match the
4888 indicated template PARM. Returns the converted ARG, or
4889 error_mark_node if the conversion was unsuccessful. Error and
4890 warning messages are issued under control of COMPLAIN. This
4891 conversion is for the Ith parameter in the parameter list. ARGS is
4892 the full set of template arguments deduced so far. */
4895 convert_template_argument (tree parm,
4898 tsubst_flags_t complain,
4904 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
4906 if (TREE_CODE (arg) == TREE_LIST
4907 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
4909 /* The template argument was the name of some
4910 member function. That's usually
4911 invalid, but static members are OK. In any
4912 case, grab the underlying fields/functions
4913 and issue an error later if required. */
4914 orig_arg = TREE_VALUE (arg);
4915 TREE_TYPE (arg) = unknown_type_node;
4920 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
4921 requires_type = (TREE_CODE (parm) == TYPE_DECL
4922 || requires_tmpl_type);
4924 /* When determining whether an argument pack expansion is a template,
4925 look at the pattern. */
4926 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
4927 arg = PACK_EXPANSION_PATTERN (arg);
4930 ((TREE_CODE (arg) == TEMPLATE_DECL
4931 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
4932 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
4933 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
4936 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
4937 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
4938 arg = TYPE_STUB_DECL (arg);
4940 is_type = TYPE_P (arg) || is_tmpl_type;
4942 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
4943 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
4945 permerror (input_location, "to refer to a type member of a template parameter, "
4946 "use %<typename %E%>", orig_arg);
4948 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
4949 TREE_OPERAND (arg, 1),
4951 complain & tf_error);
4955 if (is_type != requires_type)
4959 if (complain & tf_error)
4961 error ("type/value mismatch at argument %d in template "
4962 "parameter list for %qD",
4965 error (" expected a constant of type %qT, got %qT",
4967 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
4968 else if (requires_tmpl_type)
4969 error (" expected a class template, got %qE", orig_arg);
4971 error (" expected a type, got %qE", orig_arg);
4974 return error_mark_node;
4976 if (is_tmpl_type ^ requires_tmpl_type)
4978 if (in_decl && (complain & tf_error))
4980 error ("type/value mismatch at argument %d in template "
4981 "parameter list for %qD",
4984 error (" expected a type, got %qT", DECL_NAME (arg));
4986 error (" expected a class template, got %qT", orig_arg);
4988 return error_mark_node;
4993 if (requires_tmpl_type)
4995 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
4996 /* The number of argument required is not known yet.
4997 Just accept it for now. */
4998 val = TREE_TYPE (arg);
5001 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5004 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5006 if (coerce_template_template_parms (parmparm, argparm,
5012 /* TEMPLATE_TEMPLATE_PARM node is preferred over
5014 if (val != error_mark_node)
5016 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
5017 val = TREE_TYPE (val);
5018 else if (TREE_CODE (val) == TYPE_PACK_EXPANSION
5019 && DECL_TEMPLATE_TEMPLATE_PARM_P (arg))
5021 val = TREE_TYPE (arg);
5022 val = make_pack_expansion (val);
5028 if (in_decl && (complain & tf_error))
5030 error ("type/value mismatch at argument %d in "
5031 "template parameter list for %qD",
5033 error (" expected a template of type %qD, got %qD",
5037 val = error_mark_node;
5043 /* We only form one instance of each template specialization.
5044 Therefore, if we use a non-canonical variant (i.e., a
5045 typedef), any future messages referring to the type will use
5046 the typedef, which is confusing if those future uses do not
5047 themselves also use the typedef. */
5049 val = canonical_type_variant (val);
5053 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
5055 if (invalid_nontype_parm_type_p (t, complain))
5056 return error_mark_node;
5058 if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
5059 /* We used to call digest_init here. However, digest_init
5060 will report errors, which we don't want when complain
5061 is zero. More importantly, digest_init will try too
5062 hard to convert things: for example, `0' should not be
5063 converted to pointer type at this point according to
5064 the standard. Accepting this is not merely an
5065 extension, since deciding whether or not these
5066 conversions can occur is part of determining which
5067 function template to call, or whether a given explicit
5068 argument specification is valid. */
5069 val = convert_nontype_argument (t, orig_arg);
5073 if (val == NULL_TREE)
5074 val = error_mark_node;
5075 else if (val == error_mark_node && (complain & tf_error))
5076 error ("could not convert template argument %qE to %qT", orig_arg, t);
5082 /* Coerces the remaining template arguments in INNER_ARGS (from
5083 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
5084 Returns the coerced argument pack. PARM_IDX is the position of this
5085 parameter in the template parameter list. ARGS is the original
5086 template argument list. */
5088 coerce_template_parameter_pack (tree parms,
5096 tsubst_flags_t complain)
5098 tree parm = TREE_VEC_ELT (parms, parm_idx);
5099 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5102 tree packed_types = NULL_TREE;
5104 if (arg_idx > nargs)
5107 packed_args = make_tree_vec (nargs - arg_idx);
5109 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
5110 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
5112 /* When the template parameter is a non-type template
5113 parameter pack whose type uses parameter packs, we need
5114 to look at each of the template arguments
5115 separately. Build a vector of the types for these
5116 non-type template parameters in PACKED_TYPES. */
5118 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
5119 packed_types = tsubst_pack_expansion (expansion, args,
5122 if (packed_types == error_mark_node)
5123 return error_mark_node;
5125 /* Check that we have the right number of arguments. */
5127 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
5128 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
5131 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
5132 error ("wrong number of template arguments (%d, should be %d)",
5133 nargs, needed_parms);
5134 return error_mark_node;
5137 /* If we aren't able to check the actual arguments now
5138 (because they haven't been expanded yet), we can at least
5139 verify that all of the types used for the non-type
5140 template parameter pack are, in fact, valid for non-type
5141 template parameters. */
5143 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
5145 int j, len = TREE_VEC_LENGTH (packed_types);
5146 for (j = 0; j < len; ++j)
5148 tree t = TREE_VEC_ELT (packed_types, j);
5149 if (invalid_nontype_parm_type_p (t, complain))
5150 return error_mark_node;
5155 /* Convert the remaining arguments, which will be a part of the
5156 parameter pack "parm". */
5157 for (; arg_idx < nargs; ++arg_idx)
5159 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
5160 tree actual_parm = TREE_VALUE (parm);
5162 if (packed_types && !PACK_EXPANSION_P (arg))
5164 /* When we have a vector of types (corresponding to the
5165 non-type template parameter pack that uses parameter
5166 packs in its type, as mention above), and the
5167 argument is not an expansion (which expands to a
5168 currently unknown number of arguments), clone the
5169 parm and give it the next type in PACKED_TYPES. */
5170 actual_parm = copy_node (actual_parm);
5171 TREE_TYPE (actual_parm) =
5172 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
5175 if (arg != error_mark_node)
5176 arg = convert_template_argument (actual_parm,
5177 arg, new_args, complain, parm_idx,
5179 if (arg == error_mark_node)
5181 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
5184 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
5185 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
5186 argument_pack = make_node (TYPE_ARGUMENT_PACK);
5189 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
5190 TREE_TYPE (argument_pack)
5191 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
5192 TREE_CONSTANT (argument_pack) = 1;
5195 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
5196 return argument_pack;
5199 /* Convert all template arguments to their appropriate types, and
5200 return a vector containing the innermost resulting template
5201 arguments. If any error occurs, return error_mark_node. Error and
5202 warning messages are issued under control of COMPLAIN.
5204 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
5205 for arguments not specified in ARGS. Otherwise, if
5206 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
5207 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
5208 USE_DEFAULT_ARGS is false, then all arguments must be specified in
5212 coerce_template_parms (tree parms,
5215 tsubst_flags_t complain,
5216 bool require_all_args,
5217 bool use_default_args)
5219 int nparms, nargs, parm_idx, arg_idx, lost = 0;
5222 tree new_inner_args;
5223 bool saved_skip_evaluation;
5225 /* When used as a boolean value, indicates whether this is a
5226 variadic template parameter list. Since it's an int, we can also
5227 subtract it from nparms to get the number of non-variadic
5232 = expand_template_argument_pack (INNERMOST_TEMPLATE_ARGS (args));
5234 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5235 nparms = TREE_VEC_LENGTH (parms);
5237 /* Determine if there are any parameter packs. */
5238 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
5240 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
5241 if (template_parameter_pack_p (tparm))
5248 if ((nargs > nparms - variadic_p && !variadic_p)
5249 || (nargs < nparms - variadic_p
5251 && (!use_default_args
5252 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
5253 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
5255 if (complain & tf_error)
5257 const char *or_more = "";
5260 or_more = " or more";
5264 error ("wrong number of template arguments (%d, should be %d%s)",
5265 nargs, nparms, or_more);
5268 error ("provided for %q+D", in_decl);
5271 return error_mark_node;
5274 /* We need to evaluate the template arguments, even though this
5275 template-id may be nested within a "sizeof". */
5276 saved_skip_evaluation = skip_evaluation;
5277 skip_evaluation = false;
5278 new_inner_args = make_tree_vec (nparms);
5279 new_args = add_outermost_template_args (args, new_inner_args);
5280 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
5285 /* Get the Ith template parameter. */
5286 parm = TREE_VEC_ELT (parms, parm_idx);
5288 if (parm == error_mark_node)
5290 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
5294 /* Calculate the next argument. */
5295 if (template_parameter_pack_p (TREE_VALUE (parm)))
5297 /* All remaining arguments will be placed in the
5298 template parameter pack PARM. */
5299 arg = coerce_template_parameter_pack (parms, parm_idx, args,
5300 inner_args, arg_idx,
5304 /* Store this argument. */
5305 if (arg == error_mark_node)
5307 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
5309 /* We are done with all of the arguments. */
5314 else if (arg_idx < nargs)
5316 arg = TREE_VEC_ELT (inner_args, arg_idx);
5318 if (arg && PACK_EXPANSION_P (arg))
5320 if (complain & tf_error)
5322 /* If ARG is a pack expansion, but PARM is not a
5323 template parameter pack (if it were, we would have
5324 handled it above), we're trying to expand into a
5325 fixed-length argument list. */
5326 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
5327 error ("cannot expand %<%E%> into a fixed-length "
5328 "argument list", arg);
5330 error ("cannot expand %<%T%> into a fixed-length "
5331 "argument list", arg);
5333 return error_mark_node;
5336 else if (require_all_args)
5337 /* There must be a default arg in this case. */
5338 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
5343 if (arg == error_mark_node)
5345 if (complain & tf_error)
5346 error ("template argument %d is invalid", arg_idx + 1);
5349 /* This only occurs if there was an error in the template
5350 parameter list itself (which we would already have
5351 reported) that we are trying to recover from, e.g., a class
5352 template with a parameter list such as
5353 template<typename..., typename>. */
5354 return error_mark_node;
5356 arg = convert_template_argument (TREE_VALUE (parm),
5357 arg, new_args, complain,
5360 if (arg == error_mark_node)
5362 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
5364 skip_evaluation = saved_skip_evaluation;
5367 return error_mark_node;
5369 return new_inner_args;
5372 /* Returns 1 if template args OT and NT are equivalent. */
5375 template_args_equal (tree ot, tree nt)
5380 if (TREE_CODE (nt) == TREE_VEC)
5381 /* For member templates */
5382 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
5383 else if (PACK_EXPANSION_P (ot))
5384 return PACK_EXPANSION_P (nt)
5385 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
5386 PACK_EXPANSION_PATTERN (nt));
5387 else if (TYPE_P (nt))
5388 return TYPE_P (ot) && same_type_p (ot, nt);
5389 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
5392 return cp_tree_equal (ot, nt);
5395 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
5396 of template arguments. Returns 0 otherwise. */
5399 comp_template_args (tree oldargs, tree newargs)
5403 oldargs = expand_template_argument_pack (oldargs);
5404 newargs = expand_template_argument_pack (newargs);
5406 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
5409 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
5411 tree nt = TREE_VEC_ELT (newargs, i);
5412 tree ot = TREE_VEC_ELT (oldargs, i);
5414 if (! template_args_equal (ot, nt))
5421 add_pending_template (tree d)
5423 tree ti = (TYPE_P (d)
5424 ? CLASSTYPE_TEMPLATE_INFO (d)
5425 : DECL_TEMPLATE_INFO (d));
5426 struct pending_template *pt;
5429 if (TI_PENDING_TEMPLATE_FLAG (ti))
5432 /* We are called both from instantiate_decl, where we've already had a
5433 tinst_level pushed, and instantiate_template, where we haven't.
5435 level = !current_tinst_level || current_tinst_level->decl != d;
5438 push_tinst_level (d);
5440 pt = GGC_NEW (struct pending_template);
5442 pt->tinst = current_tinst_level;
5443 if (last_pending_template)
5444 last_pending_template->next = pt;
5446 pending_templates = pt;
5448 last_pending_template = pt;
5450 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
5457 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
5458 ARGLIST. Valid choices for FNS are given in the cp-tree.def
5459 documentation for TEMPLATE_ID_EXPR. */
5462 lookup_template_function (tree fns, tree arglist)
5466 if (fns == error_mark_node || arglist == error_mark_node)
5467 return error_mark_node;
5469 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
5470 gcc_assert (fns && (is_overloaded_fn (fns)
5471 || TREE_CODE (fns) == IDENTIFIER_NODE));
5473 if (BASELINK_P (fns))
5475 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
5477 BASELINK_FUNCTIONS (fns),
5482 type = TREE_TYPE (fns);
5483 if (TREE_CODE (fns) == OVERLOAD || !type)
5484 type = unknown_type_node;
5486 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
5489 /* Within the scope of a template class S<T>, the name S gets bound
5490 (in build_self_reference) to a TYPE_DECL for the class, not a
5491 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
5492 or one of its enclosing classes, and that type is a template,
5493 return the associated TEMPLATE_DECL. Otherwise, the original
5494 DECL is returned. */
5497 maybe_get_template_decl_from_type_decl (tree decl)
5499 return (decl != NULL_TREE
5500 && TREE_CODE (decl) == TYPE_DECL
5501 && DECL_ARTIFICIAL (decl)
5502 && CLASS_TYPE_P (TREE_TYPE (decl))
5503 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
5504 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
5507 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
5508 parameters, find the desired type.
5510 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
5512 IN_DECL, if non-NULL, is the template declaration we are trying to
5515 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
5516 the class we are looking up.
5518 Issue error and warning messages under control of COMPLAIN.
5520 If the template class is really a local class in a template
5521 function, then the FUNCTION_CONTEXT is the function in which it is
5524 ??? Note that this function is currently called *twice* for each
5525 template-id: the first time from the parser, while creating the
5526 incomplete type (finish_template_type), and the second type during the
5527 real instantiation (instantiate_template_class). This is surely something
5528 that we want to avoid. It also causes some problems with argument
5529 coercion (see convert_nontype_argument for more information on this). */
5532 lookup_template_class (tree d1,
5537 tsubst_flags_t complain)
5539 tree templ = NULL_TREE, parmlist;
5542 timevar_push (TV_NAME_LOOKUP);
5544 if (TREE_CODE (d1) == IDENTIFIER_NODE)
5546 tree value = innermost_non_namespace_value (d1);
5547 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
5552 push_decl_namespace (context);
5553 templ = lookup_name (d1);
5554 templ = maybe_get_template_decl_from_type_decl (templ);
5556 pop_decl_namespace ();
5559 context = DECL_CONTEXT (templ);
5561 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
5563 tree type = TREE_TYPE (d1);
5565 /* If we are declaring a constructor, say A<T>::A<T>, we will get
5566 an implicit typename for the second A. Deal with it. */
5567 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
5568 type = TREE_TYPE (type);
5570 if (CLASSTYPE_TEMPLATE_INFO (type))
5572 templ = CLASSTYPE_TI_TEMPLATE (type);
5573 d1 = DECL_NAME (templ);
5576 else if (TREE_CODE (d1) == ENUMERAL_TYPE
5577 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
5579 templ = TYPE_TI_TEMPLATE (d1);
5580 d1 = DECL_NAME (templ);
5582 else if (TREE_CODE (d1) == TEMPLATE_DECL
5583 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
5586 d1 = DECL_NAME (templ);
5587 context = DECL_CONTEXT (templ);
5590 /* Issue an error message if we didn't find a template. */
5593 if (complain & tf_error)
5594 error ("%qT is not a template", d1);
5595 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5598 if (TREE_CODE (templ) != TEMPLATE_DECL
5599 /* Make sure it's a user visible template, if it was named by
5601 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
5602 && !PRIMARY_TEMPLATE_P (templ)))
5604 if (complain & tf_error)
5606 error ("non-template type %qT used as a template", d1);
5608 error ("for template declaration %q+D", in_decl);
5610 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5613 complain &= ~tf_user;
5615 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
5617 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
5618 template arguments */
5624 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
5626 /* Consider an example where a template template parameter declared as
5628 template <class T, class U = std::allocator<T> > class TT
5630 The template parameter level of T and U are one level larger than
5631 of TT. To proper process the default argument of U, say when an
5632 instantiation `TT<int>' is seen, we need to build the full
5633 arguments containing {int} as the innermost level. Outer levels,
5634 available when not appearing as default template argument, can be
5635 obtained from the arguments of the enclosing template.
5637 Suppose that TT is later substituted with std::vector. The above
5638 instantiation is `TT<int, std::allocator<T> >' with TT at
5639 level 1, and T at level 2, while the template arguments at level 1
5640 becomes {std::vector} and the inner level 2 is {int}. */
5642 outer = DECL_CONTEXT (templ);
5644 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
5645 else if (current_template_parms)
5646 /* This is an argument of the current template, so we haven't set
5647 DECL_CONTEXT yet. */
5648 outer = current_template_args ();
5651 arglist = add_to_template_args (outer, arglist);
5653 arglist2 = coerce_template_parms (parmlist, arglist, templ,
5655 /*require_all_args=*/true,
5656 /*use_default_args=*/true);
5657 if (arglist2 == error_mark_node
5658 || (!uses_template_parms (arglist2)
5659 && check_instantiated_args (templ, arglist2, complain)))
5660 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5662 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
5663 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
5667 tree template_type = TREE_TYPE (templ);
5670 tree found = NULL_TREE;
5673 int is_partial_instantiation;
5675 gen_tmpl = most_general_template (templ);
5676 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
5677 parm_depth = TMPL_PARMS_DEPTH (parmlist);
5678 arg_depth = TMPL_ARGS_DEPTH (arglist);
5680 if (arg_depth == 1 && parm_depth > 1)
5682 /* We've been given an incomplete set of template arguments.
5685 template <class T> struct S1 {
5686 template <class U> struct S2 {};
5687 template <class U> struct S2<U*> {};
5690 we will be called with an ARGLIST of `U*', but the
5691 TEMPLATE will be `template <class T> template
5692 <class U> struct S1<T>::S2'. We must fill in the missing
5695 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
5697 arg_depth = TMPL_ARGS_DEPTH (arglist);
5700 /* Now we should have enough arguments. */
5701 gcc_assert (parm_depth == arg_depth);
5703 /* From here on, we're only interested in the most general
5707 /* Calculate the BOUND_ARGS. These will be the args that are
5708 actually tsubst'd into the definition to create the
5712 /* We have multiple levels of arguments to coerce, at once. */
5714 int saved_depth = TMPL_ARGS_DEPTH (arglist);
5716 tree bound_args = make_tree_vec (parm_depth);
5718 for (i = saved_depth,
5719 t = DECL_TEMPLATE_PARMS (templ);
5720 i > 0 && t != NULL_TREE;
5721 --i, t = TREE_CHAIN (t))
5723 tree a = coerce_template_parms (TREE_VALUE (t),
5726 /*require_all_args=*/true,
5727 /*use_default_args=*/true);
5729 /* Don't process further if one of the levels fails. */
5730 if (a == error_mark_node)
5732 /* Restore the ARGLIST to its full size. */
5733 TREE_VEC_LENGTH (arglist) = saved_depth;
5734 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5737 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
5739 /* We temporarily reduce the length of the ARGLIST so
5740 that coerce_template_parms will see only the arguments
5741 corresponding to the template parameters it is
5743 TREE_VEC_LENGTH (arglist)--;
5746 /* Restore the ARGLIST to its full size. */
5747 TREE_VEC_LENGTH (arglist) = saved_depth;
5749 arglist = bound_args;
5753 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
5754 INNERMOST_TEMPLATE_ARGS (arglist),
5757 /*require_all_args=*/true,
5758 /*use_default_args=*/true);
5760 if (arglist == error_mark_node)
5761 /* We were unable to bind the arguments. */
5762 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5764 /* In the scope of a template class, explicit references to the
5765 template class refer to the type of the template, not any
5766 instantiation of it. For example, in:
5768 template <class T> class C { void f(C<T>); }
5770 the `C<T>' is just the same as `C'. Outside of the
5771 class, however, such a reference is an instantiation. */
5772 if (comp_template_args (TYPE_TI_ARGS (template_type),
5775 found = template_type;
5777 if (!entering_scope && PRIMARY_TEMPLATE_P (templ))
5781 for (ctx = current_class_type;
5782 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
5784 ? TYPE_CONTEXT (ctx)
5785 : DECL_CONTEXT (ctx)))
5786 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
5789 /* We're not in the scope of the class, so the
5790 TEMPLATE_TYPE is not the type we want after all. */
5796 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
5798 /* If we already have this specialization, return it. */
5799 found = retrieve_specialization (templ, arglist,
5800 /*class_specializations_p=*/false);
5802 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
5804 /* This type is a "partial instantiation" if any of the template
5805 arguments still involve template parameters. Note that we set
5806 IS_PARTIAL_INSTANTIATION for partial specializations as
5808 is_partial_instantiation = uses_template_parms (arglist);
5810 /* If the deduced arguments are invalid, then the binding
5812 if (!is_partial_instantiation
5813 && check_instantiated_args (templ,
5814 INNERMOST_TEMPLATE_ARGS (arglist),
5816 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5818 if (!is_partial_instantiation
5819 && !PRIMARY_TEMPLATE_P (templ)
5820 && TREE_CODE (CP_DECL_CONTEXT (templ)) == NAMESPACE_DECL)
5822 found = xref_tag_from_type (TREE_TYPE (templ),
5824 /*tag_scope=*/ts_global);
5825 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
5828 context = tsubst (DECL_CONTEXT (templ), arglist,
5831 context = global_namespace;
5833 /* Create the type. */
5834 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
5836 if (!is_partial_instantiation)
5838 set_current_access_from_decl (TYPE_NAME (template_type));
5839 t = start_enum (TYPE_IDENTIFIER (template_type),
5840 tsubst (ENUM_UNDERLYING_TYPE (template_type),
5841 arglist, complain, in_decl),
5842 SCOPED_ENUM_P (template_type));
5846 /* We don't want to call start_enum for this type, since
5847 the values for the enumeration constants may involve
5848 template parameters. And, no one should be interested
5849 in the enumeration constants for such a type. */
5850 t = make_node (ENUMERAL_TYPE);
5851 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
5856 t = make_class_type (TREE_CODE (template_type));
5857 CLASSTYPE_DECLARED_CLASS (t)
5858 = CLASSTYPE_DECLARED_CLASS (template_type);
5859 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
5860 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
5862 /* A local class. Make sure the decl gets registered properly. */
5863 if (context == current_function_decl)
5864 pushtag (DECL_NAME (templ), t, /*tag_scope=*/ts_current);
5866 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
5867 /* This instantiation is another name for the primary
5868 template type. Set the TYPE_CANONICAL field
5870 TYPE_CANONICAL (t) = template_type;
5871 else if (any_template_arguments_need_structural_equality_p (arglist))
5872 /* Some of the template arguments require structural
5873 equality testing, so this template class requires
5874 structural equality testing. */
5875 SET_TYPE_STRUCTURAL_EQUALITY (t);
5878 /* If we called start_enum or pushtag above, this information
5879 will already be set up. */
5882 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
5884 type_decl = create_implicit_typedef (DECL_NAME (templ), t);
5885 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
5886 TYPE_STUB_DECL (t) = type_decl;
5887 DECL_SOURCE_LOCATION (type_decl)
5888 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
5891 type_decl = TYPE_NAME (t);
5893 TREE_PRIVATE (type_decl)
5894 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
5895 TREE_PROTECTED (type_decl)
5896 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
5897 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
5899 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
5900 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
5903 /* Set up the template information. We have to figure out which
5904 template is the immediate parent if this is a full
5906 if (parm_depth == 1 || is_partial_instantiation
5907 || !PRIMARY_TEMPLATE_P (templ))
5908 /* This case is easy; there are no member templates involved. */
5912 /* This is a full instantiation of a member template. Look
5913 for a partial instantiation of which this is an instance. */
5915 for (found = DECL_TEMPLATE_INSTANTIATIONS (templ);
5916 found; found = TREE_CHAIN (found))
5919 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
5921 /* We only want partial instantiations, here, not
5922 specializations or full instantiations. */
5923 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
5924 || !uses_template_parms (TREE_VALUE (found)))
5927 /* Temporarily reduce by one the number of levels in the
5928 ARGLIST and in FOUND so as to avoid comparing the
5929 last set of arguments. */
5930 TREE_VEC_LENGTH (arglist)--;
5931 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
5933 /* See if the arguments match. If they do, then TMPL is
5934 the partial instantiation we want. */
5935 success = comp_template_args (TREE_PURPOSE (found), arglist);
5937 /* Restore the argument vectors to their full size. */
5938 TREE_VEC_LENGTH (arglist)++;
5939 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
5950 /* There was no partial instantiation. This happens
5951 where C<T> is a member template of A<T> and it's used
5954 template <typename T> struct B { A<T>::C<int> m; };
5957 Create the partial instantiation.
5959 TREE_VEC_LENGTH (arglist)--;
5960 found = tsubst (templ, arglist, complain, NULL_TREE);
5961 TREE_VEC_LENGTH (arglist)++;
5965 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
5966 DECL_TEMPLATE_INSTANTIATIONS (templ)
5967 = tree_cons (arglist, t,
5968 DECL_TEMPLATE_INSTANTIATIONS (templ));
5970 if (TREE_CODE (t) == ENUMERAL_TYPE
5971 && !is_partial_instantiation)
5972 /* Now that the type has been registered on the instantiations
5973 list, we set up the enumerators. Because the enumeration
5974 constants may involve the enumeration type itself, we make
5975 sure to register the type first, and then create the
5976 constants. That way, doing tsubst_expr for the enumeration
5977 constants won't result in recursive calls here; we'll find
5978 the instantiation and exit above. */
5979 tsubst_enum (template_type, t, arglist);
5981 if (is_partial_instantiation)
5982 /* If the type makes use of template parameters, the
5983 code that generates debugging information will crash. */
5984 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
5986 /* Possibly limit visibility based on template args. */
5987 TREE_PUBLIC (type_decl) = 1;
5988 determine_visibility (type_decl);
5990 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
5992 timevar_pop (TV_NAME_LOOKUP);
5999 /* True when we should also visit template parameters that occur in
6000 non-deduced contexts. */
6001 bool include_nondeduced_p;
6002 struct pointer_set_t *visited;
6005 /* Called from for_each_template_parm via walk_tree. */
6008 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
6011 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
6012 tree_fn_t fn = pfd->fn;
6013 void *data = pfd->data;
6016 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
6017 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
6018 pfd->include_nondeduced_p))
6019 return error_mark_node;
6021 switch (TREE_CODE (t))
6024 if (TYPE_PTRMEMFUNC_P (t))
6030 if (!TYPE_TEMPLATE_INFO (t))
6032 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
6033 fn, data, pfd->visited,
6034 pfd->include_nondeduced_p))
6035 return error_mark_node;
6039 if (for_each_template_parm (TYPE_MIN_VALUE (t),
6040 fn, data, pfd->visited,
6041 pfd->include_nondeduced_p)
6042 || for_each_template_parm (TYPE_MAX_VALUE (t),
6043 fn, data, pfd->visited,
6044 pfd->include_nondeduced_p))
6045 return error_mark_node;
6049 /* Since we're not going to walk subtrees, we have to do this
6051 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
6052 pfd->visited, pfd->include_nondeduced_p))
6053 return error_mark_node;
6057 /* Check the return type. */
6058 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6059 pfd->include_nondeduced_p))
6060 return error_mark_node;
6062 /* Check the parameter types. Since default arguments are not
6063 instantiated until they are needed, the TYPE_ARG_TYPES may
6064 contain expressions that involve template parameters. But,
6065 no-one should be looking at them yet. And, once they're
6066 instantiated, they don't contain template parameters, so
6067 there's no point in looking at them then, either. */
6071 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
6072 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
6073 pfd->visited, pfd->include_nondeduced_p))
6074 return error_mark_node;
6076 /* Since we've already handled the TYPE_ARG_TYPES, we don't
6077 want walk_tree walking into them itself. */
6083 if (pfd->include_nondeduced_p
6084 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
6086 pfd->include_nondeduced_p))
6087 return error_mark_node;
6092 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
6093 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
6094 pfd->visited, pfd->include_nondeduced_p))
6095 return error_mark_node;
6100 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
6101 && for_each_template_parm (DECL_INITIAL (t), fn, data,
6102 pfd->visited, pfd->include_nondeduced_p))
6103 return error_mark_node;
6104 if (DECL_CONTEXT (t)
6105 && pfd->include_nondeduced_p
6106 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
6107 pfd->visited, pfd->include_nondeduced_p))
6108 return error_mark_node;
6111 case BOUND_TEMPLATE_TEMPLATE_PARM:
6112 /* Record template parameters such as `T' inside `TT<T>'. */
6113 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
6114 pfd->include_nondeduced_p))
6115 return error_mark_node;
6118 case TEMPLATE_TEMPLATE_PARM:
6119 case TEMPLATE_TYPE_PARM:
6120 case TEMPLATE_PARM_INDEX:
6121 if (fn && (*fn)(t, data))
6122 return error_mark_node;
6124 return error_mark_node;
6128 /* A template template parameter is encountered. */
6129 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
6130 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6131 pfd->include_nondeduced_p))
6132 return error_mark_node;
6134 /* Already substituted template template parameter */
6140 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
6142 pfd->include_nondeduced_p))
6143 return error_mark_node;
6147 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
6148 && pfd->include_nondeduced_p
6149 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
6150 (TREE_TYPE (t)), fn, data,
6151 pfd->visited, pfd->include_nondeduced_p))
6152 return error_mark_node;
6157 /* If there's no type, then this thing must be some expression
6158 involving template parameters. */
6159 if (!fn && !TREE_TYPE (t))
6160 return error_mark_node;
6165 case REINTERPRET_CAST_EXPR:
6166 case CONST_CAST_EXPR:
6167 case STATIC_CAST_EXPR:
6168 case DYNAMIC_CAST_EXPR:
6172 case PSEUDO_DTOR_EXPR:
6174 return error_mark_node;
6181 /* We didn't find any template parameters we liked. */
6185 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
6186 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
6187 call FN with the parameter and the DATA.
6188 If FN returns nonzero, the iteration is terminated, and
6189 for_each_template_parm returns 1. Otherwise, the iteration
6190 continues. If FN never returns a nonzero value, the value
6191 returned by for_each_template_parm is 0. If FN is NULL, it is
6192 considered to be the function which always returns 1.
6194 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
6195 parameters that occur in non-deduced contexts. When false, only
6196 visits those template parameters that can be deduced. */
6199 for_each_template_parm (tree t, tree_fn_t fn, void* data,
6200 struct pointer_set_t *visited,
6201 bool include_nondeduced_p)
6203 struct pair_fn_data pfd;
6209 pfd.include_nondeduced_p = include_nondeduced_p;
6211 /* Walk the tree. (Conceptually, we would like to walk without
6212 duplicates, but for_each_template_parm_r recursively calls
6213 for_each_template_parm, so we would need to reorganize a fair
6214 bit to use walk_tree_without_duplicates, so we keep our own
6217 pfd.visited = visited;
6219 pfd.visited = pointer_set_create ();
6220 result = cp_walk_tree (&t,
6221 for_each_template_parm_r,
6223 pfd.visited) != NULL_TREE;
6228 pointer_set_destroy (pfd.visited);
6235 /* Returns true if T depends on any template parameter. */
6238 uses_template_parms (tree t)
6241 int saved_processing_template_decl;
6243 saved_processing_template_decl = processing_template_decl;
6244 if (!saved_processing_template_decl)
6245 processing_template_decl = 1;
6247 dependent_p = dependent_type_p (t);
6248 else if (TREE_CODE (t) == TREE_VEC)
6249 dependent_p = any_dependent_template_arguments_p (t);
6250 else if (TREE_CODE (t) == TREE_LIST)
6251 dependent_p = (uses_template_parms (TREE_VALUE (t))
6252 || uses_template_parms (TREE_CHAIN (t)));
6253 else if (TREE_CODE (t) == TYPE_DECL)
6254 dependent_p = dependent_type_p (TREE_TYPE (t));
6257 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
6258 || TREE_CODE (t) == OVERLOAD
6259 || TREE_CODE (t) == BASELINK
6260 || TREE_CODE (t) == IDENTIFIER_NODE
6261 || TREE_CODE (t) == TRAIT_EXPR
6262 || CONSTANT_CLASS_P (t))
6263 dependent_p = (type_dependent_expression_p (t)
6264 || value_dependent_expression_p (t));
6267 gcc_assert (t == error_mark_node);
6268 dependent_p = false;
6271 processing_template_decl = saved_processing_template_decl;
6276 /* Returns true if T depends on any template parameter with level LEVEL. */
6279 uses_template_parms_level (tree t, int level)
6281 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
6282 /*include_nondeduced_p=*/true);
6285 static int tinst_depth;
6286 extern int max_tinst_depth;
6287 #ifdef GATHER_STATISTICS
6290 static int tinst_level_tick;
6291 static int last_template_error_tick;
6293 /* We're starting to instantiate D; record the template instantiation context
6294 for diagnostics and to restore it later. */
6297 push_tinst_level (tree d)
6299 struct tinst_level *new_level;
6301 if (tinst_depth >= max_tinst_depth)
6303 /* If the instantiation in question still has unbound template parms,
6304 we don't really care if we can't instantiate it, so just return.
6305 This happens with base instantiation for implicit `typename'. */
6306 if (uses_template_parms (d))
6309 last_template_error_tick = tinst_level_tick;
6310 error ("template instantiation depth exceeds maximum of %d (use "
6311 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
6312 max_tinst_depth, d);
6314 print_instantiation_context ();
6319 new_level = GGC_NEW (struct tinst_level);
6320 new_level->decl = d;
6321 new_level->locus = input_location;
6322 new_level->in_system_header_p = in_system_header;
6323 new_level->next = current_tinst_level;
6324 current_tinst_level = new_level;
6327 #ifdef GATHER_STATISTICS
6328 if (tinst_depth > depth_reached)
6329 depth_reached = tinst_depth;
6336 /* We're done instantiating this template; return to the instantiation
6340 pop_tinst_level (void)
6342 /* Restore the filename and line number stashed away when we started
6343 this instantiation. */
6344 input_location = current_tinst_level->locus;
6345 current_tinst_level = current_tinst_level->next;
6350 /* We're instantiating a deferred template; restore the template
6351 instantiation context in which the instantiation was requested, which
6352 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
6355 reopen_tinst_level (struct tinst_level *level)
6357 struct tinst_level *t;
6360 for (t = level; t; t = t->next)
6363 current_tinst_level = level;
6368 /* Returns the TINST_LEVEL which gives the original instantiation
6371 struct tinst_level *
6372 outermost_tinst_level (void)
6374 struct tinst_level *level = current_tinst_level;
6377 level = level->next;
6381 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
6382 vector of template arguments, as for tsubst.
6384 Returns an appropriate tsubst'd friend declaration. */
6387 tsubst_friend_function (tree decl, tree args)
6391 if (TREE_CODE (decl) == FUNCTION_DECL
6392 && DECL_TEMPLATE_INSTANTIATION (decl)
6393 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
6394 /* This was a friend declared with an explicit template
6395 argument list, e.g.:
6399 to indicate that f was a template instantiation, not a new
6400 function declaration. Now, we have to figure out what
6401 instantiation of what template. */
6403 tree template_id, arglist, fns;
6406 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
6408 /* Friend functions are looked up in the containing namespace scope.
6409 We must enter that scope, to avoid finding member functions of the
6410 current class with same name. */
6411 push_nested_namespace (ns);
6412 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
6413 tf_warning_or_error, NULL_TREE,
6414 /*integral_constant_expression_p=*/false);
6415 pop_nested_namespace (ns);
6416 arglist = tsubst (DECL_TI_ARGS (decl), args,
6417 tf_warning_or_error, NULL_TREE);
6418 template_id = lookup_template_function (fns, arglist);
6420 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6421 tmpl = determine_specialization (template_id, new_friend,
6423 /*need_member_template=*/0,
6424 TREE_VEC_LENGTH (args),
6426 return instantiate_template (tmpl, new_args, tf_error);
6429 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6431 /* The NEW_FRIEND will look like an instantiation, to the
6432 compiler, but is not an instantiation from the point of view of
6433 the language. For example, we might have had:
6435 template <class T> struct S {
6436 template <class U> friend void f(T, U);
6439 Then, in S<int>, template <class U> void f(int, U) is not an
6440 instantiation of anything. */
6441 if (new_friend == error_mark_node)
6442 return error_mark_node;
6444 DECL_USE_TEMPLATE (new_friend) = 0;
6445 if (TREE_CODE (decl) == TEMPLATE_DECL)
6447 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
6448 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
6449 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
6452 /* The mangled name for the NEW_FRIEND is incorrect. The function
6453 is not a template instantiation and should not be mangled like
6454 one. Therefore, we forget the mangling here; we'll recompute it
6455 later if we need it. */
6456 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
6458 SET_DECL_RTL (new_friend, NULL_RTX);
6459 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
6462 if (DECL_NAMESPACE_SCOPE_P (new_friend))
6465 tree new_friend_template_info;
6466 tree new_friend_result_template_info;
6468 int new_friend_is_defn;
6470 /* We must save some information from NEW_FRIEND before calling
6471 duplicate decls since that function will free NEW_FRIEND if
6473 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
6474 new_friend_is_defn =
6475 (DECL_INITIAL (DECL_TEMPLATE_RESULT
6476 (template_for_substitution (new_friend)))
6478 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
6480 /* This declaration is a `primary' template. */
6481 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
6483 new_friend_result_template_info
6484 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
6487 new_friend_result_template_info = NULL_TREE;
6489 /* Make the init_value nonzero so pushdecl knows this is a defn. */
6490 if (new_friend_is_defn)
6491 DECL_INITIAL (new_friend) = error_mark_node;
6493 /* Inside pushdecl_namespace_level, we will push into the
6494 current namespace. However, the friend function should go
6495 into the namespace of the template. */
6496 ns = decl_namespace_context (new_friend);
6497 push_nested_namespace (ns);
6498 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
6499 pop_nested_namespace (ns);
6501 if (old_decl == error_mark_node)
6502 return error_mark_node;
6504 if (old_decl != new_friend)
6506 /* This new friend declaration matched an existing
6507 declaration. For example, given:
6509 template <class T> void f(T);
6510 template <class U> class C {
6511 template <class T> friend void f(T) {}
6514 the friend declaration actually provides the definition
6515 of `f', once C has been instantiated for some type. So,
6516 old_decl will be the out-of-class template declaration,
6517 while new_friend is the in-class definition.
6519 But, if `f' was called before this point, the
6520 instantiation of `f' will have DECL_TI_ARGS corresponding
6521 to `T' but not to `U', references to which might appear
6522 in the definition of `f'. Previously, the most general
6523 template for an instantiation of `f' was the out-of-class
6524 version; now it is the in-class version. Therefore, we
6525 run through all specialization of `f', adding to their
6526 DECL_TI_ARGS appropriately. In particular, they need a
6527 new set of outer arguments, corresponding to the
6528 arguments for this class instantiation.
6530 The same situation can arise with something like this:
6533 template <class T> class C {
6537 when `C<int>' is instantiated. Now, `f(int)' is defined
6540 if (!new_friend_is_defn)
6541 /* On the other hand, if the in-class declaration does
6542 *not* provide a definition, then we don't want to alter
6543 existing definitions. We can just leave everything
6548 /* Overwrite whatever template info was there before, if
6549 any, with the new template information pertaining to
6551 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
6553 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
6554 reregister_specialization (new_friend,
6555 most_general_template (old_decl),
6560 tree new_friend_args;
6562 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
6563 = new_friend_result_template_info;
6565 new_friend_args = TI_ARGS (new_friend_template_info);
6566 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
6570 tree spec = TREE_VALUE (t);
6573 = add_outermost_template_args (new_friend_args,
6574 DECL_TI_ARGS (spec));
6577 /* Now, since specializations are always supposed to
6578 hang off of the most general template, we must move
6580 t = most_general_template (old_decl);
6583 DECL_TEMPLATE_SPECIALIZATIONS (t)
6584 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
6585 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
6586 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
6591 /* The information from NEW_FRIEND has been merged into OLD_DECL
6592 by duplicate_decls. */
6593 new_friend = old_decl;
6598 tree context = DECL_CONTEXT (new_friend);
6602 template <class T> class C {
6603 template <class U> friend void C1<U>::f (); // case 1
6604 friend void C2<T>::f (); // case 2
6606 we only need to make sure CONTEXT is a complete type for
6607 case 2. To distinguish between the two cases, we note that
6608 CONTEXT of case 1 remains dependent type after tsubst while
6609 this isn't true for case 2. */
6610 ++processing_template_decl;
6611 dependent_p = dependent_type_p (context);
6612 --processing_template_decl;
6615 && !complete_type_or_else (context, NULL_TREE))
6616 return error_mark_node;
6618 if (COMPLETE_TYPE_P (context))
6620 /* Check to see that the declaration is really present, and,
6621 possibly obtain an improved declaration. */
6622 tree fn = check_classfn (context,
6623 new_friend, NULL_TREE);
6633 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
6634 template arguments, as for tsubst.
6636 Returns an appropriate tsubst'd friend type or error_mark_node on
6640 tsubst_friend_class (tree friend_tmpl, tree args)
6646 context = DECL_CONTEXT (friend_tmpl);
6650 if (TREE_CODE (context) == NAMESPACE_DECL)
6651 push_nested_namespace (context);
6653 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
6656 /* Look for a class template declaration. We look for hidden names
6657 because two friend declarations of the same template are the
6658 same. For example, in:
6661 template <typename> friend class F;
6663 template <typename> struct B {
6664 template <typename> friend class F;
6667 both F templates are the same. */
6668 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
6669 /*block_p=*/true, 0,
6670 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
6672 /* But, if we don't find one, it might be because we're in a
6673 situation like this:
6681 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
6682 for `S<int>', not the TEMPLATE_DECL. */
6683 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
6685 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
6686 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
6689 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
6691 /* The friend template has already been declared. Just
6692 check to see that the declarations match, and install any new
6693 default parameters. We must tsubst the default parameters,
6694 of course. We only need the innermost template parameters
6695 because that is all that redeclare_class_template will look
6697 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
6698 > TMPL_ARGS_DEPTH (args))
6701 location_t saved_input_location;
6702 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
6703 args, tf_warning_or_error);
6705 saved_input_location = input_location;
6706 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
6707 redeclare_class_template (TREE_TYPE (tmpl), parms);
6708 input_location = saved_input_location;
6712 friend_type = TREE_TYPE (tmpl);
6716 /* The friend template has not already been declared. In this
6717 case, the instantiation of the template class will cause the
6718 injection of this template into the global scope. */
6719 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
6720 if (tmpl == error_mark_node)
6721 return error_mark_node;
6723 /* The new TMPL is not an instantiation of anything, so we
6724 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
6725 the new type because that is supposed to be the corresponding
6726 template decl, i.e., TMPL. */
6727 DECL_USE_TEMPLATE (tmpl) = 0;
6728 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
6729 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
6730 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
6731 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
6733 /* Inject this template into the global scope. */
6734 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
6739 if (TREE_CODE (context) == NAMESPACE_DECL)
6740 pop_nested_namespace (context);
6742 pop_nested_class ();
6748 /* Returns zero if TYPE cannot be completed later due to circularity.
6749 Otherwise returns one. */
6752 can_complete_type_without_circularity (tree type)
6754 if (type == NULL_TREE || type == error_mark_node)
6756 else if (COMPLETE_TYPE_P (type))
6758 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
6759 return can_complete_type_without_circularity (TREE_TYPE (type));
6760 else if (CLASS_TYPE_P (type)
6761 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
6767 /* Apply any attributes which had to be deferred until instantiation
6768 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
6769 ARGS, COMPLAIN, IN_DECL are as tsubst. */
6772 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
6773 tree args, tsubst_flags_t complain, tree in_decl)
6775 tree last_dep = NULL_TREE;
6779 for (t = attributes; t; t = TREE_CHAIN (t))
6780 if (ATTR_IS_DEPENDENT (t))
6783 attributes = copy_list (attributes);
6787 if (DECL_P (*decl_p))
6789 if (TREE_TYPE (*decl_p) == error_mark_node)
6791 p = &DECL_ATTRIBUTES (*decl_p);
6794 p = &TYPE_ATTRIBUTES (*decl_p);
6798 tree late_attrs = NULL_TREE;
6799 tree *q = &late_attrs;
6801 for (*p = attributes; *p; )
6804 if (ATTR_IS_DEPENDENT (t))
6806 *p = TREE_CHAIN (t);
6807 TREE_CHAIN (t) = NULL_TREE;
6808 /* If the first attribute argument is an identifier, don't
6809 pass it through tsubst. Attributes like mode, format,
6810 cleanup and several target specific attributes expect it
6813 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
6814 && TREE_VALUE (TREE_VALUE (t))
6815 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
6816 == IDENTIFIER_NODE))
6819 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
6821 /*integral_constant_expression_p=*/false);
6822 if (chain != TREE_CHAIN (TREE_VALUE (t)))
6824 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
6829 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
6830 /*integral_constant_expression_p=*/false);
6832 q = &TREE_CHAIN (t);
6835 p = &TREE_CHAIN (t);
6838 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
6843 instantiate_class_template (tree type)
6845 tree templ, args, pattern, t, member;
6850 if (type == error_mark_node)
6851 return error_mark_node;
6853 if (TYPE_BEING_DEFINED (type)
6854 || COMPLETE_TYPE_P (type)
6855 || dependent_type_p (type))
6858 /* Figure out which template is being instantiated. */
6859 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
6860 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
6862 /* Determine what specialization of the original template to
6864 t = most_specialized_class (type, templ);
6865 if (t == error_mark_node)
6867 TYPE_BEING_DEFINED (type) = 1;
6868 return error_mark_node;
6872 /* This TYPE is actually an instantiation of a partial
6873 specialization. We replace the innermost set of ARGS with
6874 the arguments appropriate for substitution. For example,
6877 template <class T> struct S {};
6878 template <class T> struct S<T*> {};
6880 and supposing that we are instantiating S<int*>, ARGS will
6881 presently be {int*} -- but we need {int}. */
6882 pattern = TREE_TYPE (t);
6883 args = TREE_PURPOSE (t);
6887 pattern = TREE_TYPE (templ);
6888 args = CLASSTYPE_TI_ARGS (type);
6891 /* If the template we're instantiating is incomplete, then clearly
6892 there's nothing we can do. */
6893 if (!COMPLETE_TYPE_P (pattern))
6896 /* If we've recursively instantiated too many templates, stop. */
6897 if (! push_tinst_level (type))
6900 /* Now we're really doing the instantiation. Mark the type as in
6901 the process of being defined. */
6902 TYPE_BEING_DEFINED (type) = 1;
6904 /* We may be in the middle of deferred access check. Disable
6906 push_deferring_access_checks (dk_no_deferred);
6908 push_to_top_level ();
6910 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
6912 /* Set the input location to the template definition. This is needed
6913 if tsubsting causes an error. */
6914 typedecl = TYPE_MAIN_DECL (type);
6915 input_location = DECL_SOURCE_LOCATION (typedecl);
6917 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
6918 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
6919 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
6920 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
6921 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
6922 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
6923 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
6924 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
6925 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
6926 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
6927 TYPE_PACKED (type) = TYPE_PACKED (pattern);
6928 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
6929 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
6930 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
6931 if (ANON_AGGR_TYPE_P (pattern))
6932 SET_ANON_AGGR_TYPE_P (type);
6933 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
6935 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
6936 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
6939 pbinfo = TYPE_BINFO (pattern);
6941 /* We should never instantiate a nested class before its enclosing
6942 class; we need to look up the nested class by name before we can
6943 instantiate it, and that lookup should instantiate the enclosing
6945 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
6946 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
6947 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
6949 base_list = NULL_TREE;
6950 if (BINFO_N_BASE_BINFOS (pbinfo))
6953 tree context = TYPE_CONTEXT (type);
6957 /* We must enter the scope containing the type, as that is where
6958 the accessibility of types named in dependent bases are
6960 pushed_scope = push_scope (context ? context : global_namespace);
6962 /* Substitute into each of the bases to determine the actual
6964 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
6967 tree access = BINFO_BASE_ACCESS (pbinfo, i);
6968 tree expanded_bases = NULL_TREE;
6971 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
6974 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
6975 args, tf_error, NULL_TREE);
6976 if (expanded_bases == error_mark_node)
6979 len = TREE_VEC_LENGTH (expanded_bases);
6982 for (idx = 0; idx < len; idx++)
6985 /* Extract the already-expanded base class. */
6986 base = TREE_VEC_ELT (expanded_bases, idx);
6988 /* Substitute to figure out the base class. */
6989 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
6992 if (base == error_mark_node)
6995 base_list = tree_cons (access, base, base_list);
6996 if (BINFO_VIRTUAL_P (pbase_binfo))
6997 TREE_TYPE (base_list) = integer_type_node;
7001 /* The list is now in reverse order; correct that. */
7002 base_list = nreverse (base_list);
7005 pop_scope (pushed_scope);
7007 /* Now call xref_basetypes to set up all the base-class
7009 xref_basetypes (type, base_list);
7011 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
7012 (int) ATTR_FLAG_TYPE_IN_PLACE,
7013 args, tf_error, NULL_TREE);
7015 /* Now that our base classes are set up, enter the scope of the
7016 class, so that name lookups into base classes, etc. will work
7017 correctly. This is precisely analogous to what we do in
7018 begin_class_definition when defining an ordinary non-template
7019 class, except we also need to push the enclosing classes. */
7020 push_nested_class (type);
7022 /* Now members are processed in the order of declaration. */
7023 for (member = CLASSTYPE_DECL_LIST (pattern);
7024 member; member = TREE_CHAIN (member))
7026 tree t = TREE_VALUE (member);
7028 if (TREE_PURPOSE (member))
7032 /* Build new CLASSTYPE_NESTED_UTDS. */
7035 bool class_template_p;
7037 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
7038 && TYPE_LANG_SPECIFIC (t)
7039 && CLASSTYPE_IS_TEMPLATE (t));
7040 /* If the member is a class template, then -- even after
7041 substitution -- there may be dependent types in the
7042 template argument list for the class. We increment
7043 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
7044 that function will assume that no types are dependent
7045 when outside of a template. */
7046 if (class_template_p)
7047 ++processing_template_decl;
7048 newtag = tsubst (t, args, tf_error, NULL_TREE);
7049 if (class_template_p)
7050 --processing_template_decl;
7051 if (newtag == error_mark_node)
7054 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
7056 tree name = TYPE_IDENTIFIER (t);
7058 if (class_template_p)
7059 /* Unfortunately, lookup_template_class sets
7060 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
7061 instantiation (i.e., for the type of a member
7062 template class nested within a template class.)
7063 This behavior is required for
7064 maybe_process_partial_specialization to work
7065 correctly, but is not accurate in this case;
7066 the TAG is not an instantiation of anything.
7067 (The corresponding TEMPLATE_DECL is an
7068 instantiation, but the TYPE is not.) */
7069 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
7071 /* Now, we call pushtag to put this NEWTAG into the scope of
7072 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
7073 pushtag calling push_template_decl. We don't have to do
7074 this for enums because it will already have been done in
7077 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
7078 pushtag (name, newtag, /*tag_scope=*/ts_current);
7081 else if (TREE_CODE (t) == FUNCTION_DECL
7082 || DECL_FUNCTION_TEMPLATE_P (t))
7084 /* Build new TYPE_METHODS. */
7087 if (TREE_CODE (t) == TEMPLATE_DECL)
7088 ++processing_template_decl;
7089 r = tsubst (t, args, tf_error, NULL_TREE);
7090 if (TREE_CODE (t) == TEMPLATE_DECL)
7091 --processing_template_decl;
7092 set_current_access_from_decl (r);
7093 finish_member_declaration (r);
7097 /* Build new TYPE_FIELDS. */
7098 if (TREE_CODE (t) == STATIC_ASSERT)
7101 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
7102 tf_warning_or_error, NULL_TREE,
7103 /*integral_constant_expression_p=*/true);
7104 finish_static_assert (condition,
7105 STATIC_ASSERT_MESSAGE (t),
7106 STATIC_ASSERT_SOURCE_LOCATION (t),
7109 else if (TREE_CODE (t) != CONST_DECL)
7113 /* The file and line for this declaration, to
7114 assist in error message reporting. Since we
7115 called push_tinst_level above, we don't need to
7117 input_location = DECL_SOURCE_LOCATION (t);
7119 if (TREE_CODE (t) == TEMPLATE_DECL)
7120 ++processing_template_decl;
7121 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
7122 if (TREE_CODE (t) == TEMPLATE_DECL)
7123 --processing_template_decl;
7124 if (TREE_CODE (r) == VAR_DECL)
7128 [t]he initialization (and any associated
7129 side-effects) of a static data member does
7130 not occur unless the static data member is
7131 itself used in a way that requires the
7132 definition of the static data member to
7135 Therefore, we do not substitute into the
7136 initialized for the static data member here. */
7137 finish_static_data_member_decl
7140 /*init_const_expr_p=*/false,
7141 /*asmspec_tree=*/NULL_TREE,
7143 if (DECL_INITIALIZED_IN_CLASS_P (r))
7144 check_static_variable_definition (r, TREE_TYPE (r));
7146 else if (TREE_CODE (r) == FIELD_DECL)
7148 /* Determine whether R has a valid type and can be
7149 completed later. If R is invalid, then it is
7150 replaced by error_mark_node so that it will not be
7151 added to TYPE_FIELDS. */
7152 tree rtype = TREE_TYPE (r);
7153 if (can_complete_type_without_circularity (rtype))
7154 complete_type (rtype);
7156 if (!COMPLETE_TYPE_P (rtype))
7158 cxx_incomplete_type_error (r, rtype);
7159 r = error_mark_node;
7163 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
7164 such a thing will already have been added to the field
7165 list by tsubst_enum in finish_member_declaration in the
7166 CLASSTYPE_NESTED_UTDS case above. */
7167 if (!(TREE_CODE (r) == TYPE_DECL
7168 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
7169 && DECL_ARTIFICIAL (r)))
7171 set_current_access_from_decl (r);
7172 finish_member_declaration (r);
7179 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
7181 /* Build new CLASSTYPE_FRIEND_CLASSES. */
7183 tree friend_type = t;
7184 bool adjust_processing_template_decl = false;
7186 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7188 /* template <class T> friend class C; */
7189 friend_type = tsubst_friend_class (friend_type, args);
7190 adjust_processing_template_decl = true;
7192 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
7194 /* template <class T> friend class C::D; */
7195 friend_type = tsubst (friend_type, args,
7196 tf_warning_or_error, NULL_TREE);
7197 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7198 friend_type = TREE_TYPE (friend_type);
7199 adjust_processing_template_decl = true;
7201 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
7203 /* This could be either
7207 when dependent_type_p is false or
7209 template <class U> friend class T::C;
7212 friend_type = tsubst (friend_type, args,
7213 tf_warning_or_error, NULL_TREE);
7214 /* Bump processing_template_decl for correct
7215 dependent_type_p calculation. */
7216 ++processing_template_decl;
7217 if (dependent_type_p (friend_type))
7218 adjust_processing_template_decl = true;
7219 --processing_template_decl;
7221 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
7222 && hidden_name_p (TYPE_NAME (friend_type)))
7226 where C hasn't been declared yet. Let's lookup name
7227 from namespace scope directly, bypassing any name that
7228 come from dependent base class. */
7229 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
7231 /* The call to xref_tag_from_type does injection for friend
7233 push_nested_namespace (ns);
7235 xref_tag_from_type (friend_type, NULL_TREE,
7236 /*tag_scope=*/ts_current);
7237 pop_nested_namespace (ns);
7239 else if (uses_template_parms (friend_type))
7240 /* friend class C<T>; */
7241 friend_type = tsubst (friend_type, args,
7242 tf_warning_or_error, NULL_TREE);
7247 where C is already declared or
7249 friend class C<int>;
7251 We don't have to do anything in these cases. */
7253 if (adjust_processing_template_decl)
7254 /* Trick make_friend_class into realizing that the friend
7255 we're adding is a template, not an ordinary class. It's
7256 important that we use make_friend_class since it will
7257 perform some error-checking and output cross-reference
7259 ++processing_template_decl;
7261 if (friend_type != error_mark_node)
7262 make_friend_class (type, friend_type, /*complain=*/false);
7264 if (adjust_processing_template_decl)
7265 --processing_template_decl;
7269 /* Build new DECL_FRIENDLIST. */
7272 /* The file and line for this declaration, to
7273 assist in error message reporting. Since we
7274 called push_tinst_level above, we don't need to
7276 input_location = DECL_SOURCE_LOCATION (t);
7278 if (TREE_CODE (t) == TEMPLATE_DECL)
7280 ++processing_template_decl;
7281 push_deferring_access_checks (dk_no_check);
7284 r = tsubst_friend_function (t, args);
7285 add_friend (type, r, /*complain=*/false);
7286 if (TREE_CODE (t) == TEMPLATE_DECL)
7288 pop_deferring_access_checks ();
7289 --processing_template_decl;
7295 /* Set the file and line number information to whatever is given for
7296 the class itself. This puts error messages involving generated
7297 implicit functions at a predictable point, and the same point
7298 that would be used for non-template classes. */
7299 input_location = DECL_SOURCE_LOCATION (typedecl);
7301 unreverse_member_declarations (type);
7302 finish_struct_1 (type);
7303 TYPE_BEING_DEFINED (type) = 0;
7305 /* Now that the class is complete, instantiate default arguments for
7306 any member functions. We don't do this earlier because the
7307 default arguments may reference members of the class. */
7308 if (!PRIMARY_TEMPLATE_P (templ))
7309 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
7310 if (TREE_CODE (t) == FUNCTION_DECL
7311 /* Implicitly generated member functions will not have template
7312 information; they are not instantiations, but instead are
7313 created "fresh" for each instantiation. */
7314 && DECL_TEMPLATE_INFO (t))
7315 tsubst_default_arguments (t);
7317 pop_nested_class ();
7318 pop_from_top_level ();
7319 pop_deferring_access_checks ();
7322 /* The vtable for a template class can be emitted in any translation
7323 unit in which the class is instantiated. When there is no key
7324 method, however, finish_struct_1 will already have added TYPE to
7325 the keyed_classes list. */
7326 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
7327 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
7333 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7339 else if (TYPE_P (t))
7340 r = tsubst (t, args, complain, in_decl);
7343 r = tsubst_expr (t, args, complain, in_decl,
7344 /*integral_constant_expression_p=*/true);
7345 r = fold_non_dependent_expr (r);
7350 /* Substitute ARGS into T, which is an pack expansion
7351 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
7352 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
7353 (if only a partial substitution could be performed) or
7354 ERROR_MARK_NODE if there was an error. */
7356 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
7360 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
7361 tree first_arg_pack; int i, len = -1;
7365 gcc_assert (PACK_EXPANSION_P (t));
7366 pattern = PACK_EXPANSION_PATTERN (t);
7368 /* Determine the argument packs that will instantiate the parameter
7369 packs used in the expansion expression. While we're at it,
7370 compute the number of arguments to be expanded and make sure it
7372 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
7373 pack = TREE_CHAIN (pack))
7375 tree parm_pack = TREE_VALUE (pack);
7376 tree arg_pack = NULL_TREE;
7377 tree orig_arg = NULL_TREE;
7379 if (TREE_CODE (parm_pack) == PARM_DECL)
7380 arg_pack = retrieve_local_specialization (parm_pack);
7383 int level, idx, levels;
7384 template_parm_level_and_index (parm_pack, &level, &idx);
7386 levels = TMPL_ARGS_DEPTH (args);
7387 if (level <= levels)
7388 arg_pack = TMPL_ARG (args, level, idx);
7391 orig_arg = arg_pack;
7392 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
7393 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
7395 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
7396 /* This can only happen if we forget to expand an argument
7397 pack somewhere else. Just return an error, silently. */
7399 result = make_tree_vec (1);
7400 TREE_VEC_ELT (result, 0) = error_mark_node;
7405 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
7406 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
7408 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
7409 tree pattern = PACK_EXPANSION_PATTERN (expansion);
7410 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
7411 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
7412 /* The argument pack that the parameter maps to is just an
7413 expansion of the parameter itself, such as one would
7414 find in the implicit typedef of a class inside the
7415 class itself. Consider this parameter "unsubstituted",
7416 so that we will maintain the outer pack expansion. */
7417 arg_pack = NULL_TREE;
7423 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
7425 /* It's all-or-nothing with incomplete argument packs. */
7426 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7427 return error_mark_node;
7429 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7435 first_arg_pack = arg_pack;
7437 else if (len != my_len)
7439 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
7440 error ("mismatched argument pack lengths while expanding "
7444 error ("mismatched argument pack lengths while expanding "
7447 return error_mark_node;
7450 /* Keep track of the parameter packs and their corresponding
7452 packs = tree_cons (parm_pack, arg_pack, packs);
7453 TREE_TYPE (packs) = orig_arg;
7456 /* We can't substitute for this parameter pack. */
7457 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
7459 unsubstituted_packs);
7462 /* We cannot expand this expansion expression, because we don't have
7463 all of the argument packs we need. Substitute into the pattern
7464 and return a PACK_EXPANSION_*. The caller will need to deal with
7466 if (unsubstituted_packs)
7467 return make_pack_expansion (tsubst (pattern, args, complain,
7470 /* We could not find any argument packs that work. */
7472 return error_mark_node;
7474 /* For each argument in each argument pack, substitute into the
7476 result = make_tree_vec (len + incomplete);
7477 for (i = 0; i < len + incomplete; ++i)
7479 /* For parameter pack, change the substitution of the parameter
7480 pack to the ith argument in its argument pack, then expand
7482 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7484 tree parm = TREE_PURPOSE (pack);
7486 if (TREE_CODE (parm) == PARM_DECL)
7488 /* Select the Ith argument from the pack. */
7489 tree arg = make_node (ARGUMENT_PACK_SELECT);
7490 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
7491 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
7493 register_local_specialization (arg, parm);
7499 template_parm_level_and_index (parm, &level, &idx);
7503 /* Select the Ith argument from the pack. */
7504 value = make_node (ARGUMENT_PACK_SELECT);
7505 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
7506 ARGUMENT_PACK_SELECT_INDEX (value) = i;
7509 /* Update the corresponding argument. */
7510 TMPL_ARG (args, level, idx) = value;
7514 /* Substitute into the PATTERN with the altered arguments. */
7515 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
7516 TREE_VEC_ELT (result, i) =
7517 tsubst_expr (pattern, args, complain, in_decl,
7518 /*integral_constant_expression_p=*/false);
7520 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
7523 /* When we have incomplete argument packs, the last "expanded"
7524 result is itself a pack expansion, which allows us
7525 to deduce more arguments. */
7526 TREE_VEC_ELT (result, i) =
7527 make_pack_expansion (TREE_VEC_ELT (result, i));
7529 if (TREE_VEC_ELT (result, i) == error_mark_node)
7531 result = error_mark_node;
7536 /* Update ARGS to restore the substitution from parameter packs to
7537 their argument packs. */
7538 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7540 tree parm = TREE_PURPOSE (pack);
7542 if (TREE_CODE (parm) == PARM_DECL)
7543 register_local_specialization (TREE_TYPE (pack), parm);
7547 template_parm_level_and_index (parm, &level, &idx);
7549 /* Update the corresponding argument. */
7550 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
7551 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
7554 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
7561 /* Substitute ARGS into the vector or list of template arguments T. */
7564 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7567 int len = TREE_VEC_LENGTH (t);
7568 int need_new = 0, i, expanded_len_adjust = 0, out;
7569 tree *elts = (tree *) alloca (len * sizeof (tree));
7571 for (i = 0; i < len; i++)
7573 tree orig_arg = TREE_VEC_ELT (t, i);
7576 if (TREE_CODE (orig_arg) == TREE_VEC)
7577 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
7578 else if (PACK_EXPANSION_P (orig_arg))
7580 /* Substitute into an expansion expression. */
7581 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
7583 if (TREE_CODE (new_arg) == TREE_VEC)
7584 /* Add to the expanded length adjustment the number of
7585 expanded arguments. We subtract one from this
7586 measurement, because the argument pack expression
7587 itself is already counted as 1 in
7588 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
7589 the argument pack is empty. */
7590 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
7592 else if (ARGUMENT_PACK_P (orig_arg))
7594 /* Substitute into each of the arguments. */
7595 new_arg = make_node (TREE_CODE (orig_arg));
7597 SET_ARGUMENT_PACK_ARGS (
7599 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
7600 args, complain, in_decl));
7602 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
7603 new_arg = error_mark_node;
7605 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
7606 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
7608 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
7610 if (TREE_TYPE (new_arg) == error_mark_node)
7611 new_arg = error_mark_node;
7615 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
7617 if (new_arg == error_mark_node)
7618 return error_mark_node;
7621 if (new_arg != orig_arg)
7628 /* Make space for the expanded arguments coming from template
7630 t = make_tree_vec (len + expanded_len_adjust);
7631 for (i = 0, out = 0; i < len; i++)
7633 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
7634 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
7635 && TREE_CODE (elts[i]) == TREE_VEC)
7639 /* Now expand the template argument pack "in place". */
7640 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
7641 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
7645 TREE_VEC_ELT (t, out) = elts[i];
7653 /* Return the result of substituting ARGS into the template parameters
7654 given by PARMS. If there are m levels of ARGS and m + n levels of
7655 PARMS, then the result will contain n levels of PARMS. For
7656 example, if PARMS is `template <class T> template <class U>
7657 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
7658 result will be `template <int*, double, class V>'. */
7661 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
7666 /* When substituting into a template, we must set
7667 PROCESSING_TEMPLATE_DECL as the template parameters may be
7668 dependent if they are based on one-another, and the dependency
7669 predicates are short-circuit outside of templates. */
7670 ++processing_template_decl;
7672 for (new_parms = &r;
7673 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
7674 new_parms = &(TREE_CHAIN (*new_parms)),
7675 parms = TREE_CHAIN (parms))
7678 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
7681 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
7687 if (parms == error_mark_node)
7690 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
7692 if (tuple == error_mark_node)
7695 default_value = TREE_PURPOSE (tuple);
7696 parm_decl = TREE_VALUE (tuple);
7698 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
7699 if (TREE_CODE (parm_decl) == PARM_DECL
7700 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
7701 parm_decl = error_mark_node;
7702 default_value = tsubst_template_arg (default_value, args,
7703 complain, NULL_TREE);
7705 tuple = build_tree_list (default_value, parm_decl);
7706 TREE_VEC_ELT (new_vec, i) = tuple;
7710 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
7711 - TMPL_ARGS_DEPTH (args)),
7712 new_vec, NULL_TREE);
7715 --processing_template_decl;
7720 /* Substitute the ARGS into the indicated aggregate (or enumeration)
7721 type T. If T is not an aggregate or enumeration type, it is
7722 handled as if by tsubst. IN_DECL is as for tsubst. If
7723 ENTERING_SCOPE is nonzero, T is the context for a template which
7724 we are presently tsubst'ing. Return the substituted value. */
7727 tsubst_aggr_type (tree t,
7729 tsubst_flags_t complain,
7736 switch (TREE_CODE (t))
7739 if (TYPE_PTRMEMFUNC_P (t))
7740 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
7742 /* Else fall through. */
7745 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
7750 bool saved_skip_evaluation;
7752 /* In "sizeof(X<I>)" we need to evaluate "I". */
7753 saved_skip_evaluation = skip_evaluation;
7754 skip_evaluation = false;
7756 /* First, determine the context for the type we are looking
7758 context = TYPE_CONTEXT (t);
7761 context = tsubst_aggr_type (context, args, complain,
7762 in_decl, /*entering_scope=*/1);
7763 /* If context is a nested class inside a class template,
7764 it may still need to be instantiated (c++/33959). */
7765 if (TYPE_P (context))
7766 context = complete_type (context);
7769 /* Then, figure out what arguments are appropriate for the
7770 type we are trying to find. For example, given:
7772 template <class T> struct S;
7773 template <class T, class U> void f(T, U) { S<U> su; }
7775 and supposing that we are instantiating f<int, double>,
7776 then our ARGS will be {int, double}, but, when looking up
7777 S we only want {double}. */
7778 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
7780 if (argvec == error_mark_node)
7781 r = error_mark_node;
7784 r = lookup_template_class (t, argvec, in_decl, context,
7785 entering_scope, complain);
7786 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7789 skip_evaluation = saved_skip_evaluation;
7794 /* This is not a template type, so there's nothing to do. */
7798 return tsubst (t, args, complain, in_decl);
7802 /* Substitute into the default argument ARG (a default argument for
7803 FN), which has the indicated TYPE. */
7806 tsubst_default_argument (tree fn, tree type, tree arg)
7808 tree saved_class_ptr = NULL_TREE;
7809 tree saved_class_ref = NULL_TREE;
7811 /* This default argument came from a template. Instantiate the
7812 default argument here, not in tsubst. In the case of
7821 we must be careful to do name lookup in the scope of S<T>,
7822 rather than in the current class. */
7823 push_access_scope (fn);
7824 /* The "this" pointer is not valid in a default argument. */
7827 saved_class_ptr = current_class_ptr;
7828 cp_function_chain->x_current_class_ptr = NULL_TREE;
7829 saved_class_ref = current_class_ref;
7830 cp_function_chain->x_current_class_ref = NULL_TREE;
7833 push_deferring_access_checks(dk_no_deferred);
7834 /* The default argument expression may cause implicitly defined
7835 member functions to be synthesized, which will result in garbage
7836 collection. We must treat this situation as if we were within
7837 the body of function so as to avoid collecting live data on the
7840 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
7841 tf_warning_or_error, NULL_TREE,
7842 /*integral_constant_expression_p=*/false);
7844 pop_deferring_access_checks();
7846 /* Restore the "this" pointer. */
7849 cp_function_chain->x_current_class_ptr = saved_class_ptr;
7850 cp_function_chain->x_current_class_ref = saved_class_ref;
7853 pop_access_scope (fn);
7855 /* Make sure the default argument is reasonable. */
7856 arg = check_default_argument (type, arg);
7861 /* Substitute into all the default arguments for FN. */
7864 tsubst_default_arguments (tree fn)
7869 tmpl_args = DECL_TI_ARGS (fn);
7871 /* If this function is not yet instantiated, we certainly don't need
7872 its default arguments. */
7873 if (uses_template_parms (tmpl_args))
7876 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
7878 arg = TREE_CHAIN (arg))
7879 if (TREE_PURPOSE (arg))
7880 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
7882 TREE_PURPOSE (arg));
7885 /* Substitute the ARGS into the T, which is a _DECL. Return the
7886 result of the substitution. Issue error and warning messages under
7887 control of COMPLAIN. */
7890 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
7892 location_t saved_loc;
7896 /* Set the filename and linenumber to improve error-reporting. */
7897 saved_loc = input_location;
7898 input_location = DECL_SOURCE_LOCATION (t);
7900 switch (TREE_CODE (t))
7904 /* We can get here when processing a member function template,
7905 member class template, and template template parameter of
7906 a template class. */
7907 tree decl = DECL_TEMPLATE_RESULT (t);
7912 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7914 /* Template template parameter is treated here. */
7915 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7916 if (new_type == error_mark_node)
7917 return error_mark_node;
7920 TREE_CHAIN (r) = NULL_TREE;
7921 TREE_TYPE (r) = new_type;
7922 DECL_TEMPLATE_RESULT (r)
7923 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
7924 DECL_TEMPLATE_PARMS (r)
7925 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
7927 TYPE_NAME (new_type) = r;
7931 /* We might already have an instance of this template.
7932 The ARGS are for the surrounding class type, so the
7933 full args contain the tsubst'd args for the context,
7934 plus the innermost args from the template decl. */
7935 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
7936 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
7937 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
7938 /* Because this is a template, the arguments will still be
7939 dependent, even after substitution. If
7940 PROCESSING_TEMPLATE_DECL is not set, the dependency
7941 predicates will short-circuit. */
7942 ++processing_template_decl;
7943 full_args = tsubst_template_args (tmpl_args, args,
7945 --processing_template_decl;
7946 if (full_args == error_mark_node)
7947 return error_mark_node;
7949 /* tsubst_template_args doesn't copy the vector if
7950 nothing changed. But, *something* should have
7952 gcc_assert (full_args != tmpl_args);
7954 spec = retrieve_specialization (t, full_args,
7955 /*class_specializations_p=*/true);
7956 if (spec != NULL_TREE)
7962 /* Make a new template decl. It will be similar to the
7963 original, but will record the current template arguments.
7964 We also create a new function declaration, which is just
7965 like the old one, but points to this new template, rather
7966 than the old one. */
7968 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
7969 TREE_CHAIN (r) = NULL_TREE;
7971 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
7973 if (TREE_CODE (decl) == TYPE_DECL)
7976 ++processing_template_decl;
7977 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7978 --processing_template_decl;
7979 if (new_type == error_mark_node)
7980 return error_mark_node;
7982 TREE_TYPE (r) = new_type;
7983 CLASSTYPE_TI_TEMPLATE (new_type) = r;
7984 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
7985 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
7986 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
7991 ++processing_template_decl;
7992 new_decl = tsubst (decl, args, complain, in_decl);
7993 --processing_template_decl;
7994 if (new_decl == error_mark_node)
7995 return error_mark_node;
7997 DECL_TEMPLATE_RESULT (r) = new_decl;
7998 DECL_TI_TEMPLATE (new_decl) = r;
7999 TREE_TYPE (r) = TREE_TYPE (new_decl);
8000 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
8001 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
8004 SET_DECL_IMPLICIT_INSTANTIATION (r);
8005 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
8006 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
8008 /* The template parameters for this new template are all the
8009 template parameters for the old template, except the
8010 outermost level of parameters. */
8011 DECL_TEMPLATE_PARMS (r)
8012 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8015 if (PRIMARY_TEMPLATE_P (t))
8016 DECL_PRIMARY_TEMPLATE (r) = r;
8018 if (TREE_CODE (decl) != TYPE_DECL)
8019 /* Record this non-type partial instantiation. */
8020 register_specialization (r, t,
8021 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
8029 tree argvec = NULL_TREE;
8037 /* Nobody should be tsubst'ing into non-template functions. */
8038 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
8040 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
8045 /* If T is not dependent, just return it. We have to
8046 increment PROCESSING_TEMPLATE_DECL because
8047 value_dependent_expression_p assumes that nothing is
8048 dependent when PROCESSING_TEMPLATE_DECL is zero. */
8049 ++processing_template_decl;
8050 dependent_p = value_dependent_expression_p (t);
8051 --processing_template_decl;
8055 /* Calculate the most general template of which R is a
8056 specialization, and the complete set of arguments used to
8058 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
8059 argvec = tsubst_template_args (DECL_TI_ARGS
8060 (DECL_TEMPLATE_RESULT (gen_tmpl)),
8061 args, complain, in_decl);
8063 /* Check to see if we already have this specialization. */
8064 spec = retrieve_specialization (gen_tmpl, argvec,
8065 /*class_specializations_p=*/false);
8073 /* We can see more levels of arguments than parameters if
8074 there was a specialization of a member template, like
8077 template <class T> struct S { template <class U> void f(); }
8078 template <> template <class U> void S<int>::f(U);
8080 Here, we'll be substituting into the specialization,
8081 because that's where we can find the code we actually
8082 want to generate, but we'll have enough arguments for
8083 the most general template.
8085 We also deal with the peculiar case:
8087 template <class T> struct S {
8088 template <class U> friend void f();
8090 template <class U> void f() {}
8092 template void f<double>();
8094 Here, the ARGS for the instantiation of will be {int,
8095 double}. But, we only need as many ARGS as there are
8096 levels of template parameters in CODE_PATTERN. We are
8097 careful not to get fooled into reducing the ARGS in
8100 template <class T> struct S { template <class U> void f(U); }
8101 template <class T> template <> void S<T>::f(int) {}
8103 which we can spot because the pattern will be a
8104 specialization in this case. */
8105 args_depth = TMPL_ARGS_DEPTH (args);
8107 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
8108 if (args_depth > parms_depth
8109 && !DECL_TEMPLATE_SPECIALIZATION (t))
8110 args = get_innermost_template_args (args, parms_depth);
8114 /* This special case arises when we have something like this:
8116 template <class T> struct S {
8117 friend void f<int>(int, double);
8120 Here, the DECL_TI_TEMPLATE for the friend declaration
8121 will be an IDENTIFIER_NODE. We are being called from
8122 tsubst_friend_function, and we want only to create a
8123 new decl (R) with appropriate types so that we can call
8124 determine_specialization. */
8125 gen_tmpl = NULL_TREE;
8128 if (DECL_CLASS_SCOPE_P (t))
8130 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
8134 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
8135 complain, t, /*entering_scope=*/1);
8140 ctx = DECL_CONTEXT (t);
8142 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8143 if (type == error_mark_node)
8144 return error_mark_node;
8146 /* We do NOT check for matching decls pushed separately at this
8147 point, as they may not represent instantiations of this
8148 template, and in any case are considered separate under the
8151 DECL_USE_TEMPLATE (r) = 0;
8152 TREE_TYPE (r) = type;
8153 /* Clear out the mangled name and RTL for the instantiation. */
8154 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8155 SET_DECL_RTL (r, NULL_RTX);
8156 /* Leave DECL_INITIAL set on deleted instantiations. */
8157 if (!DECL_DELETED_FN (r))
8158 DECL_INITIAL (r) = NULL_TREE;
8159 DECL_CONTEXT (r) = ctx;
8161 if (member && DECL_CONV_FN_P (r))
8162 /* Type-conversion operator. Reconstruct the name, in
8163 case it's the name of one of the template's parameters. */
8164 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
8166 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
8168 DECL_RESULT (r) = NULL_TREE;
8170 TREE_STATIC (r) = 0;
8171 TREE_PUBLIC (r) = TREE_PUBLIC (t);
8172 DECL_EXTERNAL (r) = 1;
8173 /* If this is an instantiation of a function with internal
8174 linkage, we already know what object file linkage will be
8175 assigned to the instantiation. */
8176 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
8177 DECL_DEFER_OUTPUT (r) = 0;
8178 TREE_CHAIN (r) = NULL_TREE;
8179 DECL_PENDING_INLINE_INFO (r) = 0;
8180 DECL_PENDING_INLINE_P (r) = 0;
8181 DECL_SAVED_TREE (r) = NULL_TREE;
8182 DECL_STRUCT_FUNCTION (r) = NULL;
8184 if (DECL_CLONED_FUNCTION (r))
8186 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
8188 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
8189 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
8192 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
8193 this in the special friend case mentioned above where
8194 GEN_TMPL is NULL. */
8197 DECL_TEMPLATE_INFO (r)
8198 = tree_cons (gen_tmpl, argvec, NULL_TREE);
8199 SET_DECL_IMPLICIT_INSTANTIATION (r);
8200 register_specialization (r, gen_tmpl, argvec, false);
8202 /* We're not supposed to instantiate default arguments
8203 until they are called, for a template. But, for a
8206 template <class T> void f ()
8207 { extern void g(int i = T()); }
8209 we should do the substitution when the template is
8210 instantiated. We handle the member function case in
8211 instantiate_class_template since the default arguments
8212 might refer to other members of the class. */
8214 && !PRIMARY_TEMPLATE_P (gen_tmpl)
8215 && !uses_template_parms (argvec))
8216 tsubst_default_arguments (r);
8219 DECL_TEMPLATE_INFO (r) = NULL_TREE;
8221 /* Copy the list of befriending classes. */
8222 for (friends = &DECL_BEFRIENDING_CLASSES (r);
8224 friends = &TREE_CHAIN (*friends))
8226 *friends = copy_node (*friends);
8227 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
8232 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
8234 maybe_retrofit_in_chrg (r);
8235 if (DECL_CONSTRUCTOR_P (r))
8236 grok_ctor_properties (ctx, r);
8237 /* If this is an instantiation of a member template, clone it.
8238 If it isn't, that'll be handled by
8239 clone_constructors_and_destructors. */
8240 if (PRIMARY_TEMPLATE_P (gen_tmpl))
8241 clone_function_decl (r, /*update_method_vec_p=*/0);
8243 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r))
8244 && !grok_op_properties (r, (complain & tf_error) != 0))
8245 return error_mark_node;
8247 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
8248 SET_DECL_FRIEND_CONTEXT (r,
8249 tsubst (DECL_FRIEND_CONTEXT (t),
8250 args, complain, in_decl));
8252 /* Possibly limit visibility based on template args. */
8253 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8254 if (DECL_VISIBILITY_SPECIFIED (t))
8256 DECL_VISIBILITY_SPECIFIED (r) = 0;
8258 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8260 determine_visibility (r);
8262 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8263 args, complain, in_decl);
8269 tree type = NULL_TREE;
8271 tree expanded_types = NULL_TREE;
8272 tree prev_r = NULL_TREE;
8273 tree first_r = NULL_TREE;
8275 if (FUNCTION_PARAMETER_PACK_P (t))
8277 /* If there is a local specialization that isn't a
8278 parameter pack, it means that we're doing a "simple"
8279 substitution from inside tsubst_pack_expansion. Just
8280 return the local specialization (which will be a single
8282 tree spec = retrieve_local_specialization (t);
8284 && TREE_CODE (spec) == PARM_DECL
8285 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
8288 /* Expand the TYPE_PACK_EXPANSION that provides the types for
8289 the parameters in this function parameter pack. */
8290 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
8292 if (TREE_CODE (expanded_types) == TREE_VEC)
8294 len = TREE_VEC_LENGTH (expanded_types);
8296 /* Zero-length parameter packs are boring. Just substitute
8299 return tsubst (TREE_CHAIN (t), args, complain,
8304 /* All we did was update the type. Make a note of that. */
8305 type = expanded_types;
8306 expanded_types = NULL_TREE;
8310 /* Loop through all of the parameter's we'll build. When T is
8311 a function parameter pack, LEN is the number of expanded
8312 types in EXPANDED_TYPES; otherwise, LEN is 1. */
8314 for (i = 0; i < len; ++i)
8318 if (DECL_TEMPLATE_PARM_P (t))
8319 SET_DECL_TEMPLATE_PARM_P (r);
8322 /* We're on the Ith parameter of the function parameter
8325 /* Get the Ith type. */
8326 type = TREE_VEC_ELT (expanded_types, i);
8329 /* Rename the parameter to include the index. */
8331 make_ith_pack_parameter_name (DECL_NAME (r), i);
8334 /* We're dealing with a normal parameter. */
8335 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8337 type = type_decays_to (type);
8338 TREE_TYPE (r) = type;
8339 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8341 if (DECL_INITIAL (r))
8343 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
8344 DECL_INITIAL (r) = TREE_TYPE (r);
8346 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
8350 DECL_CONTEXT (r) = NULL_TREE;
8352 if (!DECL_TEMPLATE_PARM_P (r))
8353 DECL_ARG_TYPE (r) = type_passed_as (type);
8355 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8356 args, complain, in_decl);
8358 /* Keep track of the first new parameter we
8359 generate. That's what will be returned to the
8364 /* Build a proper chain of parameters when substituting
8365 into a function parameter pack. */
8367 TREE_CHAIN (prev_r) = r;
8371 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
8372 complain, TREE_CHAIN (t));
8374 /* FIRST_R contains the start of the chain we've built. */
8384 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8385 if (type == error_mark_node)
8386 return error_mark_node;
8387 TREE_TYPE (r) = type;
8388 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8390 /* DECL_INITIAL gives the number of bits in a bit-field. */
8392 = tsubst_expr (DECL_INITIAL (t), args,
8394 /*integral_constant_expression_p=*/true);
8395 /* We don't have to set DECL_CONTEXT here; it is set by
8396 finish_member_declaration. */
8397 TREE_CHAIN (r) = NULL_TREE;
8398 if (VOID_TYPE_P (type))
8399 error ("instantiation of %q+D as type %qT", r, type);
8401 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8402 args, complain, in_decl);
8407 /* We reach here only for member using decls. */
8408 if (DECL_DEPENDENT_P (t))
8410 r = do_class_using_decl
8411 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
8412 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
8414 r = error_mark_node;
8419 TREE_CHAIN (r) = NULL_TREE;
8426 tree argvec = NULL_TREE;
8427 tree gen_tmpl = NULL_TREE;
8429 tree tmpl = NULL_TREE;
8431 tree type = NULL_TREE;
8434 if (TREE_CODE (t) == TYPE_DECL
8435 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
8437 /* If this is the canonical decl, we don't have to
8438 mess with instantiations, and often we can't (for
8439 typename, template type parms and such). Note that
8440 TYPE_NAME is not correct for the above test if
8441 we've copied the type for a typedef. */
8442 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8443 if (type == error_mark_node)
8444 return error_mark_node;
8445 r = TYPE_NAME (type);
8449 /* Check to see if we already have the specialization we
8452 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
8454 /* T is a static data member or namespace-scope entity.
8455 We have to substitute into namespace-scope variables
8456 (even though such entities are never templates) because
8459 template <class T> void f() { extern T t; }
8461 where the entity referenced is not known until
8462 instantiation time. */
8464 ctx = DECL_CONTEXT (t);
8465 if (DECL_CLASS_SCOPE_P (t))
8467 ctx = tsubst_aggr_type (ctx, args,
8469 in_decl, /*entering_scope=*/1);
8470 /* If CTX is unchanged, then T is in fact the
8471 specialization we want. That situation occurs when
8472 referencing a static data member within in its own
8473 class. We can use pointer equality, rather than
8474 same_type_p, because DECL_CONTEXT is always
8476 if (ctx == DECL_CONTEXT (t))
8482 tmpl = DECL_TI_TEMPLATE (t);
8483 gen_tmpl = most_general_template (tmpl);
8484 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
8485 spec = (retrieve_specialization
8487 /*class_specializations_p=*/false));
8492 /* A local variable. */
8494 /* Subsequent calls to pushdecl will fill this in. */
8496 spec = retrieve_local_specialization (t);
8498 /* If we already have the specialization we need, there is
8499 nothing more to do. */
8506 /* Create a new node for the specialization we need. */
8508 if (type == NULL_TREE)
8509 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8510 if (TREE_CODE (r) == VAR_DECL)
8512 /* Even if the original location is out of scope, the
8513 newly substituted one is not. */
8514 DECL_DEAD_FOR_LOCAL (r) = 0;
8515 DECL_INITIALIZED_P (r) = 0;
8516 DECL_TEMPLATE_INSTANTIATED (r) = 0;
8517 if (type == error_mark_node)
8518 return error_mark_node;
8519 if (TREE_CODE (type) == FUNCTION_TYPE)
8521 /* It may seem that this case cannot occur, since:
8526 declares a function, not a variable. However:
8529 template <typename T> void g() { T t; }
8530 template void g<f>();
8532 is an attempt to declare a variable with function
8534 error ("variable %qD has function type",
8535 /* R is not yet sufficiently initialized, so we
8536 just use its name. */
8538 return error_mark_node;
8540 type = complete_type (type);
8541 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
8542 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
8543 type = check_var_type (DECL_NAME (r), type);
8545 if (DECL_HAS_VALUE_EXPR_P (t))
8547 tree ve = DECL_VALUE_EXPR (t);
8548 ve = tsubst_expr (ve, args, complain, in_decl,
8549 /*constant_expression_p=*/false);
8550 SET_DECL_VALUE_EXPR (r, ve);
8553 else if (DECL_SELF_REFERENCE_P (t))
8554 SET_DECL_SELF_REFERENCE_P (r);
8555 TREE_TYPE (r) = type;
8556 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8557 DECL_CONTEXT (r) = ctx;
8558 /* Clear out the mangled name and RTL for the instantiation. */
8559 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8560 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8561 SET_DECL_RTL (r, NULL_RTX);
8562 /* The initializer must not be expanded until it is required;
8564 DECL_INITIAL (r) = NULL_TREE;
8565 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8566 SET_DECL_RTL (r, NULL_RTX);
8567 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
8568 if (TREE_CODE (r) == VAR_DECL)
8570 /* Possibly limit visibility based on template args. */
8571 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8572 if (DECL_VISIBILITY_SPECIFIED (t))
8574 DECL_VISIBILITY_SPECIFIED (r) = 0;
8576 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8578 determine_visibility (r);
8580 /* Preserve a typedef that names a type. */
8581 else if (TREE_CODE (r) == TYPE_DECL
8582 && DECL_ORIGINAL_TYPE (t)
8583 && type != error_mark_node)
8585 DECL_ORIGINAL_TYPE (r) = tsubst (DECL_ORIGINAL_TYPE (t),
8586 args, complain, in_decl);
8587 TREE_TYPE (r) = type = build_variant_type_copy (type);
8588 TYPE_NAME (type) = r;
8593 /* A static data member declaration is always marked
8594 external when it is declared in-class, even if an
8595 initializer is present. We mimic the non-template
8597 DECL_EXTERNAL (r) = 1;
8599 register_specialization (r, gen_tmpl, argvec, false);
8600 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
8601 SET_DECL_IMPLICIT_INSTANTIATION (r);
8604 register_local_specialization (r, t);
8606 TREE_CHAIN (r) = NULL_TREE;
8608 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
8609 (int) ATTR_FLAG_TYPE_IN_PLACE,
8610 args, complain, in_decl);
8619 /* Restore the file and line information. */
8620 input_location = saved_loc;
8625 /* Substitute into the ARG_TYPES of a function type. */
8628 tsubst_arg_types (tree arg_types,
8630 tsubst_flags_t complain,
8633 tree remaining_arg_types;
8634 tree type = NULL_TREE;
8636 tree expanded_args = NULL_TREE;
8639 if (!arg_types || arg_types == void_list_node)
8642 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
8643 args, complain, in_decl);
8644 if (remaining_arg_types == error_mark_node)
8645 return error_mark_node;
8647 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
8649 /* For a pack expansion, perform substitution on the
8650 entire expression. Later on, we'll handle the arguments
8652 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
8653 args, complain, in_decl);
8655 if (TREE_CODE (expanded_args) == TREE_VEC)
8656 /* So that we'll spin through the parameters, one by one. */
8657 i = TREE_VEC_LENGTH (expanded_args);
8660 /* We only partially substituted into the parameter
8661 pack. Our type is TYPE_PACK_EXPANSION. */
8662 type = expanded_args;
8663 expanded_args = NULL_TREE;
8671 type = TREE_VEC_ELT (expanded_args, i);
8673 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
8675 if (type == error_mark_node)
8676 return error_mark_node;
8677 if (VOID_TYPE_P (type))
8679 if (complain & tf_error)
8681 error ("invalid parameter type %qT", type);
8683 error ("in declaration %q+D", in_decl);
8685 return error_mark_node;
8688 /* Do array-to-pointer, function-to-pointer conversion, and ignore
8689 top-level qualifiers as required. */
8690 type = TYPE_MAIN_VARIANT (type_decays_to (type));
8692 /* We do not substitute into default arguments here. The standard
8693 mandates that they be instantiated only when needed, which is
8694 done in build_over_call. */
8695 default_arg = TREE_PURPOSE (arg_types);
8697 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
8699 /* We've instantiated a template before its default arguments
8700 have been parsed. This can happen for a nested template
8701 class, and is not an error unless we require the default
8702 argument in a call of this function. */
8703 remaining_arg_types =
8704 tree_cons (default_arg, type, remaining_arg_types);
8705 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
8706 remaining_arg_types);
8709 remaining_arg_types =
8710 hash_tree_cons (default_arg, type, remaining_arg_types);
8713 return remaining_arg_types;
8716 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
8717 *not* handle the exception-specification for FNTYPE, because the
8718 initial substitution of explicitly provided template parameters
8719 during argument deduction forbids substitution into the
8720 exception-specification:
8724 All references in the function type of the function template to the
8725 corresponding template parameters are replaced by the specified tem-
8726 plate argument values. If a substitution in a template parameter or
8727 in the function type of the function template results in an invalid
8728 type, type deduction fails. [Note: The equivalent substitution in
8729 exception specifications is done only when the function is instanti-
8730 ated, at which point a program is ill-formed if the substitution
8731 results in an invalid type.] */
8734 tsubst_function_type (tree t,
8736 tsubst_flags_t complain,
8743 /* The TYPE_CONTEXT is not used for function/method types. */
8744 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
8746 /* Substitute the return type. */
8747 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8748 if (return_type == error_mark_node)
8749 return error_mark_node;
8750 /* The standard does not presently indicate that creation of a
8751 function type with an invalid return type is a deduction failure.
8752 However, that is clearly analogous to creating an array of "void"
8753 or a reference to a reference. This is core issue #486. */
8754 if (TREE_CODE (return_type) == ARRAY_TYPE
8755 || TREE_CODE (return_type) == FUNCTION_TYPE)
8757 if (complain & tf_error)
8759 if (TREE_CODE (return_type) == ARRAY_TYPE)
8760 error ("function returning an array");
8762 error ("function returning a function");
8764 return error_mark_node;
8767 /* Substitute the argument types. */
8768 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
8770 if (arg_types == error_mark_node)
8771 return error_mark_node;
8773 /* Construct a new type node and return it. */
8774 if (TREE_CODE (t) == FUNCTION_TYPE)
8775 fntype = build_function_type (return_type, arg_types);
8778 tree r = TREE_TYPE (TREE_VALUE (arg_types));
8779 if (! MAYBE_CLASS_TYPE_P (r))
8783 Type deduction may fail for any of the following
8786 -- Attempting to create "pointer to member of T" when T
8787 is not a class type. */
8788 if (complain & tf_error)
8789 error ("creating pointer to member function of non-class type %qT",
8791 return error_mark_node;
8794 fntype = build_method_type_directly (r, return_type,
8795 TREE_CHAIN (arg_types));
8797 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
8798 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
8803 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
8804 ARGS into that specification, and return the substituted
8805 specification. If there is no specification, return NULL_TREE. */
8808 tsubst_exception_specification (tree fntype,
8810 tsubst_flags_t complain,
8816 specs = TYPE_RAISES_EXCEPTIONS (fntype);
8817 new_specs = NULL_TREE;
8820 if (! TREE_VALUE (specs))
8827 tree expanded_specs = NULL_TREE;
8829 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
8831 /* Expand the pack expansion type. */
8832 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
8836 if (expanded_specs == error_mark_node)
8837 return error_mark_node;
8838 else if (TREE_CODE (expanded_specs) == TREE_VEC)
8839 len = TREE_VEC_LENGTH (expanded_specs);
8842 /* We're substituting into a member template, so
8843 we got a TYPE_PACK_EXPANSION back. Add that
8844 expansion and move on. */
8845 gcc_assert (TREE_CODE (expanded_specs)
8846 == TYPE_PACK_EXPANSION);
8847 new_specs = add_exception_specifier (new_specs,
8850 specs = TREE_CHAIN (specs);
8855 for (i = 0; i < len; ++i)
8858 spec = TREE_VEC_ELT (expanded_specs, i);
8860 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
8861 if (spec == error_mark_node)
8863 new_specs = add_exception_specifier (new_specs, spec,
8867 specs = TREE_CHAIN (specs);
8873 /* Take the tree structure T and replace template parameters used
8874 therein with the argument vector ARGS. IN_DECL is an associated
8875 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
8876 Issue error and warning messages under control of COMPLAIN. Note
8877 that we must be relatively non-tolerant of extensions here, in
8878 order to preserve conformance; if we allow substitutions that
8879 should not be allowed, we may allow argument deductions that should
8880 not succeed, and therefore report ambiguous overload situations
8881 where there are none. In theory, we could allow the substitution,
8882 but indicate that it should have failed, and allow our caller to
8883 make sure that the right thing happens, but we don't try to do this
8886 This function is used for dealing with types, decls and the like;
8887 for expressions, use tsubst_expr or tsubst_copy. */
8890 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8894 if (t == NULL_TREE || t == error_mark_node
8895 || t == integer_type_node
8896 || t == void_type_node
8897 || t == char_type_node
8898 || t == unknown_type_node
8899 || TREE_CODE (t) == NAMESPACE_DECL)
8903 return tsubst_decl (t, args, complain);
8905 if (TREE_CODE (t) == IDENTIFIER_NODE)
8906 type = IDENTIFIER_TYPE_VALUE (t);
8908 type = TREE_TYPE (t);
8910 gcc_assert (type != unknown_type_node);
8912 /* Reuse typedefs. We need to do this to handle dependent attributes,
8913 such as attribute aligned. */
8916 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
8918 tree decl = TYPE_NAME (t);
8920 if (DECL_CLASS_SCOPE_P (decl)
8921 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
8922 && uses_template_parms (DECL_CONTEXT (decl)))
8924 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
8925 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
8926 r = retrieve_specialization (tmpl, gen_args, false);
8928 else if (DECL_FUNCTION_SCOPE_P (decl)
8929 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
8930 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
8931 r = retrieve_local_specialization (decl);
8933 /* The typedef is from a non-template context. */
8939 r = cp_build_qualified_type_real
8940 (r, cp_type_quals (t) | cp_type_quals (r),
8941 complain | tf_ignore_bad_quals);
8944 /* Else we must be instantiating the typedef, so fall through. */
8948 && TREE_CODE (t) != TYPENAME_TYPE
8949 && TREE_CODE (t) != IDENTIFIER_NODE
8950 && TREE_CODE (t) != FUNCTION_TYPE
8951 && TREE_CODE (t) != METHOD_TYPE)
8952 type = tsubst (type, args, complain, in_decl);
8953 if (type == error_mark_node)
8954 return error_mark_node;
8956 switch (TREE_CODE (t))
8961 return tsubst_aggr_type (t, args, complain, in_decl,
8962 /*entering_scope=*/0);
8965 case IDENTIFIER_NODE:
8977 if (t == integer_type_node)
8980 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
8981 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
8985 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
8987 max = tsubst_expr (omax, args, complain, in_decl,
8988 /*integral_constant_expression_p=*/false);
8989 max = fold_decl_constant_value (max);
8991 if (TREE_CODE (max) != INTEGER_CST
8992 && !at_function_scope_p ()
8993 && !value_dependent_expression_p (max))
8995 if (complain & tf_error)
8996 error ("array bound is not an integer constant");
8997 return error_mark_node;
9002 Type deduction may fail for any of the following
9005 Attempting to create an array with a size that is
9006 zero or negative. */
9007 if (integer_zerop (max) && !(complain & tf_error))
9008 /* We must fail if performing argument deduction (as
9009 indicated by the state of complain), so that
9010 another substitution can be found. */
9011 return error_mark_node;
9012 else if (TREE_CODE (max) == INTEGER_CST
9013 && INT_CST_LT (max, integer_zero_node))
9015 if (complain & tf_error)
9016 error ("creating array with negative size (%qE)", max);
9018 return error_mark_node;
9021 return compute_array_index_type (NULL_TREE, max);
9024 case TEMPLATE_TYPE_PARM:
9025 case TEMPLATE_TEMPLATE_PARM:
9026 case BOUND_TEMPLATE_TEMPLATE_PARM:
9027 case TEMPLATE_PARM_INDEX:
9032 tree arg = NULL_TREE;
9036 gcc_assert (TREE_VEC_LENGTH (args) > 0);
9037 template_parm_level_and_index (t, &level, &idx);
9039 levels = TMPL_ARGS_DEPTH (args);
9040 if (level <= levels)
9042 arg = TMPL_ARG (args, level, idx);
9044 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
9045 /* See through ARGUMENT_PACK_SELECT arguments. */
9046 arg = ARGUMENT_PACK_SELECT_ARG (arg);
9049 if (arg == error_mark_node)
9050 return error_mark_node;
9051 else if (arg != NULL_TREE)
9053 if (ARGUMENT_PACK_P (arg))
9054 /* If ARG is an argument pack, we don't actually want to
9055 perform a substitution here, because substitutions
9056 for argument packs are only done
9057 element-by-element. We can get to this point when
9058 substituting the type of a non-type template
9059 parameter pack, when that type actually contains
9060 template parameter packs from an outer template, e.g.,
9062 template<typename... Types> struct A {
9063 template<Types... Values> struct B { };
9067 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
9070 gcc_assert (TYPE_P (arg));
9072 /* cv-quals from the template are discarded when
9073 substituting in a function or reference type. */
9074 if (TREE_CODE (arg) == FUNCTION_TYPE
9075 || TREE_CODE (arg) == METHOD_TYPE
9076 || TREE_CODE (arg) == REFERENCE_TYPE)
9077 quals = cp_type_quals (arg);
9079 quals = cp_type_quals (arg) | cp_type_quals (t);
9081 return cp_build_qualified_type_real
9082 (arg, quals, complain | tf_ignore_bad_quals);
9084 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9086 /* We are processing a type constructed from a
9087 template template parameter. */
9088 tree argvec = tsubst (TYPE_TI_ARGS (t),
9089 args, complain, in_decl);
9090 if (argvec == error_mark_node)
9091 return error_mark_node;
9093 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
9094 are resolving nested-types in the signature of a
9095 member function templates. Otherwise ARG is a
9096 TEMPLATE_DECL and is the real template to be
9098 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
9099 arg = TYPE_NAME (arg);
9101 r = lookup_template_class (arg,
9104 /*entering_scope=*/0,
9106 return cp_build_qualified_type_real
9107 (r, TYPE_QUALS (t), complain);
9110 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
9115 /* This can happen during the attempted tsubst'ing in
9116 unify. This means that we don't yet have any information
9117 about the template parameter in question. */
9120 /* If we get here, we must have been looking at a parm for a
9121 more deeply nested template. Make a new version of this
9122 template parameter, but with a lower level. */
9123 switch (TREE_CODE (t))
9125 case TEMPLATE_TYPE_PARM:
9126 case TEMPLATE_TEMPLATE_PARM:
9127 case BOUND_TEMPLATE_TEMPLATE_PARM:
9128 if (cp_type_quals (t))
9130 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
9131 r = cp_build_qualified_type_real
9132 (r, cp_type_quals (t),
9133 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
9134 ? tf_ignore_bad_quals : 0));
9139 TEMPLATE_TYPE_PARM_INDEX (r)
9140 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
9141 r, levels, args, complain);
9142 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
9143 TYPE_MAIN_VARIANT (r) = r;
9144 TYPE_POINTER_TO (r) = NULL_TREE;
9145 TYPE_REFERENCE_TO (r) = NULL_TREE;
9147 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
9148 /* We have reduced the level of the template
9149 template parameter, but not the levels of its
9150 template parameters, so canonical_type_parameter
9151 will not be able to find the canonical template
9152 template parameter for this level. Thus, we
9153 require structural equality checking to compare
9154 TEMPLATE_TEMPLATE_PARMs. */
9155 SET_TYPE_STRUCTURAL_EQUALITY (r);
9156 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
9157 SET_TYPE_STRUCTURAL_EQUALITY (r);
9159 TYPE_CANONICAL (r) = canonical_type_parameter (r);
9161 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9163 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
9165 if (argvec == error_mark_node)
9166 return error_mark_node;
9168 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
9169 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
9174 case TEMPLATE_PARM_INDEX:
9175 r = reduce_template_parm_level (t, type, levels, args, complain);
9187 tree purpose, value, chain;
9189 if (t == void_list_node)
9192 purpose = TREE_PURPOSE (t);
9195 purpose = tsubst (purpose, args, complain, in_decl);
9196 if (purpose == error_mark_node)
9197 return error_mark_node;
9199 value = TREE_VALUE (t);
9202 value = tsubst (value, args, complain, in_decl);
9203 if (value == error_mark_node)
9204 return error_mark_node;
9206 chain = TREE_CHAIN (t);
9207 if (chain && chain != void_type_node)
9209 chain = tsubst (chain, args, complain, in_decl);
9210 if (chain == error_mark_node)
9211 return error_mark_node;
9213 if (purpose == TREE_PURPOSE (t)
9214 && value == TREE_VALUE (t)
9215 && chain == TREE_CHAIN (t))
9217 return hash_tree_cons (purpose, value, chain);
9221 /* We should never be tsubsting a binfo. */
9225 /* A vector of template arguments. */
9227 return tsubst_template_args (t, args, complain, in_decl);
9230 case REFERENCE_TYPE:
9232 enum tree_code code;
9234 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
9237 code = TREE_CODE (t);
9242 Type deduction may fail for any of the following
9245 -- Attempting to create a pointer to reference type.
9246 -- Attempting to create a reference to a reference type or
9247 a reference to void.
9249 Core issue 106 says that creating a reference to a reference
9250 during instantiation is no longer a cause for failure. We
9251 only enforce this check in strict C++98 mode. */
9252 if ((TREE_CODE (type) == REFERENCE_TYPE
9253 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
9254 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
9256 static location_t last_loc;
9258 /* We keep track of the last time we issued this error
9259 message to avoid spewing a ton of messages during a
9260 single bad template instantiation. */
9261 if (complain & tf_error
9262 && last_loc != input_location)
9264 if (TREE_CODE (type) == VOID_TYPE)
9265 error ("forming reference to void");
9267 error ("forming %s to reference type %qT",
9268 (code == POINTER_TYPE) ? "pointer" : "reference",
9270 last_loc = input_location;
9273 return error_mark_node;
9275 else if (code == POINTER_TYPE)
9277 r = build_pointer_type (type);
9278 if (TREE_CODE (type) == METHOD_TYPE)
9279 r = build_ptrmemfunc_type (r);
9281 else if (TREE_CODE (type) == REFERENCE_TYPE)
9282 /* In C++0x, during template argument substitution, when there is an
9283 attempt to create a reference to a reference type, reference
9284 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
9286 "If a template-argument for a template-parameter T names a type
9287 that is a reference to a type A, an attempt to create the type
9288 'lvalue reference to cv T' creates the type 'lvalue reference to
9289 A,' while an attempt to create the type type rvalue reference to
9290 cv T' creates the type T"
9292 r = cp_build_reference_type
9294 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
9296 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
9297 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
9299 if (r != error_mark_node)
9300 /* Will this ever be needed for TYPE_..._TO values? */
9307 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
9308 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
9312 Type deduction may fail for any of the following
9315 -- Attempting to create "pointer to member of T" when T
9316 is not a class type. */
9317 if (complain & tf_error)
9318 error ("creating pointer to member of non-class type %qT", r);
9319 return error_mark_node;
9321 if (TREE_CODE (type) == REFERENCE_TYPE)
9323 if (complain & tf_error)
9324 error ("creating pointer to member reference type %qT", type);
9325 return error_mark_node;
9327 if (TREE_CODE (type) == VOID_TYPE)
9329 if (complain & tf_error)
9330 error ("creating pointer to member of type void");
9331 return error_mark_node;
9333 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
9334 if (TREE_CODE (type) == FUNCTION_TYPE)
9336 /* The type of the implicit object parameter gets its
9337 cv-qualifiers from the FUNCTION_TYPE. */
9339 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
9340 cp_type_quals (type));
9342 method_type = build_method_type_directly (this_type,
9344 TYPE_ARG_TYPES (type));
9345 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
9346 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
9350 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
9359 fntype = tsubst_function_type (t, args, complain, in_decl);
9360 if (fntype == error_mark_node)
9361 return error_mark_node;
9363 /* Substitute the exception specification. */
9364 specs = tsubst_exception_specification (t, args, complain,
9366 if (specs == error_mark_node)
9367 return error_mark_node;
9369 fntype = build_exception_variant (fntype, specs);
9374 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
9375 if (domain == error_mark_node)
9376 return error_mark_node;
9378 /* As an optimization, we avoid regenerating the array type if
9379 it will obviously be the same as T. */
9380 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
9383 /* These checks should match the ones in grokdeclarator.
9387 The deduction may fail for any of the following reasons:
9389 -- Attempting to create an array with an element type that
9390 is void, a function type, or a reference type, or [DR337]
9391 an abstract class type. */
9392 if (TREE_CODE (type) == VOID_TYPE
9393 || TREE_CODE (type) == FUNCTION_TYPE
9394 || TREE_CODE (type) == REFERENCE_TYPE)
9396 if (complain & tf_error)
9397 error ("creating array of %qT", type);
9398 return error_mark_node;
9400 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
9402 if (complain & tf_error)
9403 error ("creating array of %qT, which is an abstract class type",
9405 return error_mark_node;
9408 r = build_cplus_array_type (type, domain);
9410 if (TYPE_USER_ALIGN (t))
9412 TYPE_ALIGN (r) = TYPE_ALIGN (t);
9413 TYPE_USER_ALIGN (r) = 1;
9422 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9423 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9425 if (e1 == error_mark_node || e2 == error_mark_node)
9426 return error_mark_node;
9428 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
9434 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9435 if (e == error_mark_node)
9436 return error_mark_node;
9438 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
9443 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9444 in_decl, /*entering_scope=*/1);
9445 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
9448 if (ctx == error_mark_node || f == error_mark_node)
9449 return error_mark_node;
9451 if (!MAYBE_CLASS_TYPE_P (ctx))
9453 if (complain & tf_error)
9454 error ("%qT is not a class, struct, or union type", ctx);
9455 return error_mark_node;
9457 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
9459 /* Normally, make_typename_type does not require that the CTX
9460 have complete type in order to allow things like:
9462 template <class T> struct S { typename S<T>::X Y; };
9464 But, such constructs have already been resolved by this
9465 point, so here CTX really should have complete type, unless
9466 it's a partial instantiation. */
9467 ctx = complete_type (ctx);
9468 if (!COMPLETE_TYPE_P (ctx))
9470 if (complain & tf_error)
9471 cxx_incomplete_type_error (NULL_TREE, ctx);
9472 return error_mark_node;
9476 f = make_typename_type (ctx, f, typename_type,
9477 (complain & tf_error) | tf_keep_type_decl);
9478 if (f == error_mark_node)
9480 if (TREE_CODE (f) == TYPE_DECL)
9482 complain |= tf_ignore_bad_quals;
9486 if (TREE_CODE (f) != TYPENAME_TYPE)
9488 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
9489 error ("%qT resolves to %qT, which is not an enumeration type",
9491 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
9492 error ("%qT resolves to %qT, which is is not a class type",
9496 return cp_build_qualified_type_real
9497 (f, cp_type_quals (f) | cp_type_quals (t), complain);
9500 case UNBOUND_CLASS_TEMPLATE:
9502 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9503 in_decl, /*entering_scope=*/1);
9504 tree name = TYPE_IDENTIFIER (t);
9505 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
9507 if (ctx == error_mark_node || name == error_mark_node)
9508 return error_mark_node;
9511 parm_list = tsubst_template_parms (parm_list, args, complain);
9512 return make_unbound_class_template (ctx, name, parm_list, complain);
9522 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9523 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
9524 /*integral_constant_expression_p=*/false);
9525 if (e1 == error_mark_node || e2 == error_mark_node)
9526 return error_mark_node;
9528 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
9533 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9534 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9535 if (e1 == error_mark_node || e2 == error_mark_node)
9536 return error_mark_node;
9538 return build_qualified_name (/*type=*/NULL_TREE,
9539 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
9546 type = finish_typeof (tsubst_expr
9547 (TYPEOF_TYPE_EXPR (t), args,
9549 /*integral_constant_expression_p=*/false));
9550 return cp_build_qualified_type_real (type,
9552 | cp_type_quals (type),
9562 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
9564 /*integral_constant_expression_p=*/false);
9569 finish_decltype_type (type,
9570 DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
9571 return cp_build_qualified_type_real (type,
9573 | cp_type_quals (type),
9577 case TYPE_ARGUMENT_PACK:
9578 case NONTYPE_ARGUMENT_PACK:
9580 tree r = make_node (TREE_CODE (t));
9582 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
9586 SET_ARGUMENT_PACK_ARGS (r, packed_out);
9588 /* For template nontype argument packs, also substitute into
9590 if (TREE_CODE (t) == NONTYPE_ARGUMENT_PACK)
9591 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
9598 sorry ("use of %qs in template",
9599 tree_code_name [(int) TREE_CODE (t)]);
9600 return error_mark_node;
9604 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
9605 type of the expression on the left-hand side of the "." or "->"
9609 tsubst_baselink (tree baselink, tree object_type,
9610 tree args, tsubst_flags_t complain, tree in_decl)
9613 tree qualifying_scope;
9616 tree template_args = 0;
9617 bool template_id_p = false;
9619 /* A baselink indicates a function from a base class. Both the
9620 BASELINK_ACCESS_BINFO and the base class referenced may
9621 indicate bases of the template class, rather than the
9622 instantiated class. In addition, lookups that were not
9623 ambiguous before may be ambiguous now. Therefore, we perform
9624 the lookup again. */
9625 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
9626 qualifying_scope = tsubst (qualifying_scope, args,
9628 fns = BASELINK_FUNCTIONS (baselink);
9629 optype = BASELINK_OPTYPE (baselink);
9630 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
9632 template_id_p = true;
9633 template_args = TREE_OPERAND (fns, 1);
9634 fns = TREE_OPERAND (fns, 0);
9636 template_args = tsubst_template_args (template_args, args,
9639 name = DECL_NAME (get_first_fn (fns));
9640 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
9642 /* If lookup found a single function, mark it as used at this
9643 point. (If it lookup found multiple functions the one selected
9644 later by overload resolution will be marked as used at that
9646 if (BASELINK_P (baselink))
9647 fns = BASELINK_FUNCTIONS (baselink);
9648 if (!template_id_p && !really_overloaded_fn (fns))
9649 mark_used (OVL_CURRENT (fns));
9651 /* Add back the template arguments, if present. */
9652 if (BASELINK_P (baselink) && template_id_p)
9653 BASELINK_FUNCTIONS (baselink)
9654 = build_nt (TEMPLATE_ID_EXPR,
9655 BASELINK_FUNCTIONS (baselink),
9657 /* Update the conversion operator type. */
9658 BASELINK_OPTYPE (baselink)
9659 = tsubst (optype, args, complain, in_decl);
9662 object_type = current_class_type;
9663 return adjust_result_of_qualified_name_lookup (baselink,
9668 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
9669 true if the qualified-id will be a postfix-expression in-and-of
9670 itself; false if more of the postfix-expression follows the
9671 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
9675 tsubst_qualified_id (tree qualified_id, tree args,
9676 tsubst_flags_t complain, tree in_decl,
9677 bool done, bool address_p)
9685 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
9687 /* Figure out what name to look up. */
9688 name = TREE_OPERAND (qualified_id, 1);
9689 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
9692 template_args = TREE_OPERAND (name, 1);
9694 template_args = tsubst_template_args (template_args, args,
9696 name = TREE_OPERAND (name, 0);
9700 is_template = false;
9701 template_args = NULL_TREE;
9704 /* Substitute into the qualifying scope. When there are no ARGS, we
9705 are just trying to simplify a non-dependent expression. In that
9706 case the qualifying scope may be dependent, and, in any case,
9707 substituting will not help. */
9708 scope = TREE_OPERAND (qualified_id, 0);
9711 scope = tsubst (scope, args, complain, in_decl);
9712 expr = tsubst_copy (name, args, complain, in_decl);
9717 if (dependent_type_p (scope))
9718 return build_qualified_name (/*type=*/NULL_TREE,
9720 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
9722 if (!BASELINK_P (name) && !DECL_P (expr))
9724 if (TREE_CODE (expr) == BIT_NOT_EXPR)
9725 /* If this were actually a destructor call, it would have been
9726 parsed as such by the parser. */
9727 expr = error_mark_node;
9729 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
9730 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
9731 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
9733 if (complain & tf_error)
9735 error ("dependent-name %qE is parsed as a non-type, but "
9736 "instantiation yields a type", qualified_id);
9737 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
9739 return error_mark_node;
9745 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
9747 /* Remember that there was a reference to this entity. */
9751 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
9753 if (complain & tf_error)
9754 qualified_name_lookup_error (scope,
9755 TREE_OPERAND (qualified_id, 1),
9756 expr, input_location);
9757 return error_mark_node;
9761 expr = lookup_template_function (expr, template_args);
9763 if (expr == error_mark_node && complain & tf_error)
9764 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
9765 expr, input_location);
9766 else if (TYPE_P (scope))
9768 expr = (adjust_result_of_qualified_name_lookup
9769 (expr, scope, current_class_type));
9770 expr = (finish_qualified_id_expr
9771 (scope, expr, done, address_p,
9772 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
9773 /*template_arg_p=*/false));
9776 /* Expressions do not generally have reference type. */
9777 if (TREE_CODE (expr) != SCOPE_REF
9778 /* However, if we're about to form a pointer-to-member, we just
9779 want the referenced member referenced. */
9780 && TREE_CODE (expr) != OFFSET_REF)
9781 expr = convert_from_reference (expr);
9786 /* Like tsubst, but deals with expressions. This function just replaces
9787 template parms; to finish processing the resultant expression, use
9791 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9793 enum tree_code code;
9796 if (t == NULL_TREE || t == error_mark_node)
9799 code = TREE_CODE (t);
9804 r = retrieve_local_specialization (t);
9808 /* This can happen for a parameter name used later in a function
9809 declaration (such as in a late-specified return type).
9810 Replace it with an arbitrary expression with the same type
9811 (*(T*)0). This should only occur in an unevaluated context
9813 gcc_assert (skip_evaluation);
9814 r = non_reference (TREE_TYPE (t));
9815 r = tsubst (r, args, complain, in_decl);
9816 r = build_pointer_type (r);
9817 r = build_c_cast (r, null_node);
9818 return cp_build_indirect_ref (r, NULL, tf_warning_or_error);
9821 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
9822 r = ARGUMENT_PACK_SELECT_ARG (r);
9831 if (DECL_TEMPLATE_PARM_P (t))
9832 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
9833 /* There is no need to substitute into namespace-scope
9835 if (DECL_NAMESPACE_SCOPE_P (t))
9837 /* If ARGS is NULL, then T is known to be non-dependent. */
9838 if (args == NULL_TREE)
9839 return integral_constant_value (t);
9841 /* Unfortunately, we cannot just call lookup_name here.
9844 template <int I> int f() {
9846 struct S { void g() { E e = a; } };
9849 When we instantiate f<7>::S::g(), say, lookup_name is not
9850 clever enough to find f<7>::a. */
9852 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
9853 /*entering_scope=*/0);
9855 for (v = TYPE_VALUES (enum_type);
9858 if (TREE_PURPOSE (v) == DECL_NAME (t))
9859 return TREE_VALUE (v);
9861 /* We didn't find the name. That should never happen; if
9862 name-lookup found it during preliminary parsing, we
9863 should find it again here during instantiation. */
9869 if (DECL_CONTEXT (t))
9873 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
9874 /*entering_scope=*/1);
9875 if (ctx != DECL_CONTEXT (t))
9877 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
9880 if (complain & tf_error)
9881 error ("using invalid field %qD", t);
9882 return error_mark_node;
9892 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
9893 || local_variable_p (t))
9894 t = tsubst (t, args, complain, in_decl);
9899 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
9902 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9903 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
9904 args, complain, in_decl);
9905 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
9906 return tsubst (t, args, complain, in_decl);
9907 else if (DECL_CLASS_SCOPE_P (t)
9908 && uses_template_parms (DECL_CONTEXT (t)))
9910 /* Template template argument like the following example need
9913 template <template <class> class TT> struct C {};
9914 template <class T> struct D {
9915 template <class U> struct E {};
9920 We are processing the template argument `E' in #1 for
9921 the template instantiation #2. Originally, `E' is a
9922 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
9923 have to substitute this with one having context `D<int>'. */
9925 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
9926 return lookup_field (context, DECL_NAME(t), 0, false);
9929 /* Ordinary template template argument. */
9933 case REINTERPRET_CAST_EXPR:
9934 case CONST_CAST_EXPR:
9935 case STATIC_CAST_EXPR:
9936 case DYNAMIC_CAST_EXPR:
9939 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
9940 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
9943 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
9945 /* We only want to compute the number of arguments. */
9946 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
9950 if (TREE_CODE (expanded) == TREE_VEC)
9951 len = TREE_VEC_LENGTH (expanded);
9953 if (expanded == error_mark_node)
9954 return error_mark_node;
9955 else if (PACK_EXPANSION_P (expanded)
9956 || (TREE_CODE (expanded) == TREE_VEC
9958 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
9960 if (TREE_CODE (expanded) == TREE_VEC)
9961 expanded = TREE_VEC_ELT (expanded, len - 1);
9963 if (TYPE_P (expanded))
9964 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
9965 complain & tf_error);
9967 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
9968 complain & tf_error);
9971 return build_int_cst (size_type_node, len);
9977 case TRUTH_NOT_EXPR:
9980 case UNARY_PLUS_EXPR: /* Unary + */
9988 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
9989 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
9996 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
9997 name = TREE_OPERAND (t, 1);
9998 if (TREE_CODE (name) == BIT_NOT_EXPR)
10000 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10001 complain, in_decl);
10002 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10004 else if (TREE_CODE (name) == SCOPE_REF
10005 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
10007 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
10008 complain, in_decl);
10009 name = TREE_OPERAND (name, 1);
10010 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10011 complain, in_decl);
10012 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10013 name = build_qualified_name (/*type=*/NULL_TREE,
10015 /*template_p=*/false);
10017 else if (TREE_CODE (name) == BASELINK)
10018 name = tsubst_baselink (name,
10019 non_reference (TREE_TYPE (object)),
10023 name = tsubst_copy (name, args, complain, in_decl);
10024 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
10030 case TRUNC_DIV_EXPR:
10031 case CEIL_DIV_EXPR:
10032 case FLOOR_DIV_EXPR:
10033 case ROUND_DIV_EXPR:
10034 case EXACT_DIV_EXPR:
10038 case TRUNC_MOD_EXPR:
10039 case FLOOR_MOD_EXPR:
10040 case TRUTH_ANDIF_EXPR:
10041 case TRUTH_ORIF_EXPR:
10042 case TRUTH_AND_EXPR:
10043 case TRUTH_OR_EXPR:
10056 case COMPOUND_EXPR:
10059 case PREDECREMENT_EXPR:
10060 case PREINCREMENT_EXPR:
10061 case POSTDECREMENT_EXPR:
10062 case POSTINCREMENT_EXPR:
10064 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10065 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10068 return build_qualified_name (/*type=*/NULL_TREE,
10069 tsubst_copy (TREE_OPERAND (t, 0),
10070 args, complain, in_decl),
10071 tsubst_copy (TREE_OPERAND (t, 1),
10072 args, complain, in_decl),
10073 QUALIFIED_NAME_IS_TEMPLATE (t));
10078 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10079 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10080 NULL_TREE, NULL_TREE);
10084 int n = VL_EXP_OPERAND_LENGTH (t);
10085 tree result = build_vl_exp (CALL_EXPR, n);
10087 for (i = 0; i < n; i++)
10088 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
10089 complain, in_decl);
10095 case PSEUDO_DTOR_EXPR:
10098 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10099 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10100 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10101 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
10108 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10109 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10110 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10111 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
10118 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10119 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10120 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
10121 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
10125 case TEMPLATE_ID_EXPR:
10127 /* Substituted template arguments */
10128 tree fn = TREE_OPERAND (t, 0);
10129 tree targs = TREE_OPERAND (t, 1);
10131 fn = tsubst_copy (fn, args, complain, in_decl);
10133 targs = tsubst_template_args (targs, args, complain, in_decl);
10135 return lookup_template_function (fn, targs);
10140 tree purpose, value, chain;
10142 if (t == void_list_node)
10145 purpose = TREE_PURPOSE (t);
10147 purpose = tsubst_copy (purpose, args, complain, in_decl);
10148 value = TREE_VALUE (t);
10150 value = tsubst_copy (value, args, complain, in_decl);
10151 chain = TREE_CHAIN (t);
10152 if (chain && chain != void_type_node)
10153 chain = tsubst_copy (chain, args, complain, in_decl);
10154 if (purpose == TREE_PURPOSE (t)
10155 && value == TREE_VALUE (t)
10156 && chain == TREE_CHAIN (t))
10158 return tree_cons (purpose, value, chain);
10163 case ENUMERAL_TYPE:
10165 case TEMPLATE_TYPE_PARM:
10166 case TEMPLATE_TEMPLATE_PARM:
10167 case BOUND_TEMPLATE_TEMPLATE_PARM:
10168 case TEMPLATE_PARM_INDEX:
10170 case REFERENCE_TYPE:
10172 case FUNCTION_TYPE:
10175 case TYPENAME_TYPE:
10176 case UNBOUND_CLASS_TEMPLATE:
10178 case DECLTYPE_TYPE:
10180 return tsubst (t, args, complain, in_decl);
10182 case IDENTIFIER_NODE:
10183 if (IDENTIFIER_TYPENAME_P (t))
10185 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10186 return mangle_conv_op_name_for_type (new_type);
10192 /* This is handled by tsubst_copy_and_build. */
10193 gcc_unreachable ();
10196 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
10198 tsubst (TREE_TYPE (t), args, complain, in_decl));
10200 case CLEANUP_POINT_EXPR:
10201 /* We shouldn't have built any of these during initial template
10202 generation. Instead, they should be built during instantiation
10203 in response to the saved STMT_IS_FULL_EXPR_P setting. */
10204 gcc_unreachable ();
10207 mark_used (TREE_OPERAND (t, 1));
10210 case EXPR_PACK_EXPANSION:
10211 error ("invalid use of pack expansion expression");
10212 return error_mark_node;
10214 case NONTYPE_ARGUMENT_PACK:
10215 error ("use %<...%> to expand argument pack");
10216 return error_mark_node;
10223 /* Like tsubst_copy, but specifically for OpenMP clauses. */
10226 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
10229 tree new_clauses = NULL, nc, oc;
10231 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
10233 nc = copy_node (oc);
10234 OMP_CLAUSE_CHAIN (nc) = new_clauses;
10237 switch (OMP_CLAUSE_CODE (nc))
10239 case OMP_CLAUSE_LASTPRIVATE:
10240 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
10242 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
10243 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
10244 in_decl, /*integral_constant_expression_p=*/false);
10245 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
10246 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
10249 case OMP_CLAUSE_PRIVATE:
10250 case OMP_CLAUSE_SHARED:
10251 case OMP_CLAUSE_FIRSTPRIVATE:
10252 case OMP_CLAUSE_REDUCTION:
10253 case OMP_CLAUSE_COPYIN:
10254 case OMP_CLAUSE_COPYPRIVATE:
10255 case OMP_CLAUSE_IF:
10256 case OMP_CLAUSE_NUM_THREADS:
10257 case OMP_CLAUSE_SCHEDULE:
10258 case OMP_CLAUSE_COLLAPSE:
10259 OMP_CLAUSE_OPERAND (nc, 0)
10260 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
10261 in_decl, /*integral_constant_expression_p=*/false);
10263 case OMP_CLAUSE_NOWAIT:
10264 case OMP_CLAUSE_ORDERED:
10265 case OMP_CLAUSE_DEFAULT:
10266 case OMP_CLAUSE_UNTIED:
10269 gcc_unreachable ();
10273 return finish_omp_clauses (nreverse (new_clauses));
10276 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
10279 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
10282 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
10284 tree purpose, value, chain;
10289 if (TREE_CODE (t) != TREE_LIST)
10290 return tsubst_copy_and_build (t, args, complain, in_decl,
10291 /*function_p=*/false,
10292 /*integral_constant_expression_p=*/false);
10294 if (t == void_list_node)
10297 purpose = TREE_PURPOSE (t);
10299 purpose = RECUR (purpose);
10300 value = TREE_VALUE (t);
10302 value = RECUR (value);
10303 chain = TREE_CHAIN (t);
10304 if (chain && chain != void_type_node)
10305 chain = RECUR (chain);
10306 return tree_cons (purpose, value, chain);
10310 /* Substitute one OMP_FOR iterator. */
10313 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
10314 tree condv, tree incrv, tree *clauses,
10315 tree args, tsubst_flags_t complain, tree in_decl,
10316 bool integral_constant_expression_p)
10318 #define RECUR(NODE) \
10319 tsubst_expr ((NODE), args, complain, in_decl, \
10320 integral_constant_expression_p)
10321 tree decl, init, cond, incr;
10323 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
10324 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
10325 decl = RECUR (TREE_OPERAND (init, 0));
10326 init = TREE_OPERAND (init, 1);
10327 gcc_assert (!type_dependent_expression_p (decl));
10329 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
10331 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
10332 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
10333 if (TREE_CODE (incr) == MODIFY_EXPR)
10334 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
10335 RECUR (TREE_OPERAND (incr, 1)),
10338 incr = RECUR (incr);
10339 TREE_VEC_ELT (declv, i) = decl;
10340 TREE_VEC_ELT (initv, i) = init;
10341 TREE_VEC_ELT (condv, i) = cond;
10342 TREE_VEC_ELT (incrv, i) = incr;
10346 if (init && TREE_CODE (init) != DECL_EXPR)
10349 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
10351 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
10352 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
10353 && OMP_CLAUSE_DECL (c) == decl)
10355 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
10356 && OMP_CLAUSE_DECL (c) == decl)
10357 error ("iteration variable %qD should not be firstprivate", decl);
10358 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
10359 && OMP_CLAUSE_DECL (c) == decl)
10360 error ("iteration variable %qD should not be reduction", decl);
10364 c = build_omp_clause (OMP_CLAUSE_PRIVATE);
10365 OMP_CLAUSE_DECL (c) = decl;
10366 c = finish_omp_clauses (c);
10369 OMP_CLAUSE_CHAIN (c) = *clauses;
10374 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
10375 if (COMPARISON_CLASS_P (cond))
10376 cond = build2 (TREE_CODE (cond), boolean_type_node,
10377 RECUR (TREE_OPERAND (cond, 0)),
10378 RECUR (TREE_OPERAND (cond, 1)));
10380 cond = RECUR (cond);
10381 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
10382 switch (TREE_CODE (incr))
10384 case PREINCREMENT_EXPR:
10385 case PREDECREMENT_EXPR:
10386 case POSTINCREMENT_EXPR:
10387 case POSTDECREMENT_EXPR:
10388 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
10389 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
10392 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
10393 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
10395 tree rhs = TREE_OPERAND (incr, 1);
10396 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
10397 RECUR (TREE_OPERAND (incr, 0)),
10398 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
10399 RECUR (TREE_OPERAND (rhs, 0)),
10400 RECUR (TREE_OPERAND (rhs, 1))));
10403 incr = RECUR (incr);
10406 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
10407 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
10409 tree lhs = RECUR (TREE_OPERAND (incr, 0));
10410 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
10411 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
10412 TREE_TYPE (decl), lhs,
10413 RECUR (TREE_OPERAND (incr, 2))));
10415 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
10416 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
10417 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
10419 tree rhs = TREE_OPERAND (incr, 2);
10420 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
10421 RECUR (TREE_OPERAND (incr, 0)),
10422 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
10423 RECUR (TREE_OPERAND (rhs, 0)),
10424 RECUR (TREE_OPERAND (rhs, 1))));
10427 incr = RECUR (incr);
10430 incr = RECUR (incr);
10434 TREE_VEC_ELT (declv, i) = decl;
10435 TREE_VEC_ELT (initv, i) = init;
10436 TREE_VEC_ELT (condv, i) = cond;
10437 TREE_VEC_ELT (incrv, i) = incr;
10441 /* Like tsubst_copy for expressions, etc. but also does semantic
10445 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
10446 bool integral_constant_expression_p)
10448 #define RECUR(NODE) \
10449 tsubst_expr ((NODE), args, complain, in_decl, \
10450 integral_constant_expression_p)
10454 if (t == NULL_TREE || t == error_mark_node)
10457 if (EXPR_HAS_LOCATION (t))
10458 input_location = EXPR_LOCATION (t);
10459 if (STATEMENT_CODE_P (TREE_CODE (t)))
10460 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
10462 switch (TREE_CODE (t))
10464 case STATEMENT_LIST:
10466 tree_stmt_iterator i;
10467 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
10468 RECUR (tsi_stmt (i));
10472 case CTOR_INITIALIZER:
10473 finish_mem_initializers (tsubst_initializer_list
10474 (TREE_OPERAND (t, 0), args));
10478 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
10482 tmp = RECUR (EXPR_STMT_EXPR (t));
10483 if (EXPR_STMT_STMT_EXPR_RESULT (t))
10484 finish_stmt_expr_expr (tmp, cur_stmt_expr);
10486 finish_expr_stmt (tmp);
10490 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
10498 decl = DECL_EXPR_DECL (t);
10499 if (TREE_CODE (decl) == LABEL_DECL)
10500 finish_label_decl (DECL_NAME (decl));
10501 else if (TREE_CODE (decl) == USING_DECL)
10503 tree scope = USING_DECL_SCOPE (decl);
10504 tree name = DECL_NAME (decl);
10507 scope = RECUR (scope);
10508 decl = lookup_qualified_name (scope, name,
10509 /*is_type_p=*/false,
10510 /*complain=*/false);
10511 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
10512 qualified_name_lookup_error (scope, name, decl, input_location);
10514 do_local_using_decl (decl, scope, name);
10518 init = DECL_INITIAL (decl);
10519 decl = tsubst (decl, args, complain, in_decl);
10520 if (decl != error_mark_node)
10522 /* By marking the declaration as instantiated, we avoid
10523 trying to instantiate it. Since instantiate_decl can't
10524 handle local variables, and since we've already done
10525 all that needs to be done, that's the right thing to
10527 if (TREE_CODE (decl) == VAR_DECL)
10528 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
10529 if (TREE_CODE (decl) == VAR_DECL
10530 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
10531 /* Anonymous aggregates are a special case. */
10532 finish_anon_union (decl);
10535 maybe_push_decl (decl);
10536 if (TREE_CODE (decl) == VAR_DECL
10537 && DECL_PRETTY_FUNCTION_P (decl))
10539 /* For __PRETTY_FUNCTION__ we have to adjust the
10541 const char *const name
10542 = cxx_printable_name (current_function_decl, 2);
10543 init = cp_fname_init (name, &TREE_TYPE (decl));
10547 tree t = RECUR (init);
10550 /* If we had an initializer but it
10551 instantiated to nothing,
10552 value-initialize the object. This will
10553 only occur when the initializer was a
10554 pack expansion where the parameter packs
10555 used in that expansion were of length
10557 init = build_default_init (TREE_TYPE (decl),
10563 finish_decl (decl, init, NULL_TREE);
10568 /* A DECL_EXPR can also be used as an expression, in the condition
10569 clause of an if/for/while construct. */
10574 stmt = begin_for_stmt ();
10575 RECUR (FOR_INIT_STMT (t));
10576 finish_for_init_stmt (stmt);
10577 tmp = RECUR (FOR_COND (t));
10578 finish_for_cond (tmp, stmt);
10579 tmp = RECUR (FOR_EXPR (t));
10580 finish_for_expr (tmp, stmt);
10581 RECUR (FOR_BODY (t));
10582 finish_for_stmt (stmt);
10586 stmt = begin_while_stmt ();
10587 tmp = RECUR (WHILE_COND (t));
10588 finish_while_stmt_cond (tmp, stmt);
10589 RECUR (WHILE_BODY (t));
10590 finish_while_stmt (stmt);
10594 stmt = begin_do_stmt ();
10595 RECUR (DO_BODY (t));
10596 finish_do_body (stmt);
10597 tmp = RECUR (DO_COND (t));
10598 finish_do_stmt (tmp, stmt);
10602 stmt = begin_if_stmt ();
10603 tmp = RECUR (IF_COND (t));
10604 finish_if_stmt_cond (tmp, stmt);
10605 RECUR (THEN_CLAUSE (t));
10606 finish_then_clause (stmt);
10608 if (ELSE_CLAUSE (t))
10610 begin_else_clause (stmt);
10611 RECUR (ELSE_CLAUSE (t));
10612 finish_else_clause (stmt);
10615 finish_if_stmt (stmt);
10619 if (BIND_EXPR_BODY_BLOCK (t))
10620 stmt = begin_function_body ();
10622 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
10623 ? BCS_TRY_BLOCK : 0);
10625 RECUR (BIND_EXPR_BODY (t));
10627 if (BIND_EXPR_BODY_BLOCK (t))
10628 finish_function_body (stmt);
10630 finish_compound_stmt (stmt);
10634 finish_break_stmt ();
10637 case CONTINUE_STMT:
10638 finish_continue_stmt ();
10642 stmt = begin_switch_stmt ();
10643 tmp = RECUR (SWITCH_STMT_COND (t));
10644 finish_switch_cond (tmp, stmt);
10645 RECUR (SWITCH_STMT_BODY (t));
10646 finish_switch_stmt (stmt);
10649 case CASE_LABEL_EXPR:
10650 finish_case_label (RECUR (CASE_LOW (t)),
10651 RECUR (CASE_HIGH (t)));
10655 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
10659 tmp = GOTO_DESTINATION (t);
10660 if (TREE_CODE (tmp) != LABEL_DECL)
10661 /* Computed goto's must be tsubst'd into. On the other hand,
10662 non-computed gotos must not be; the identifier in question
10663 will have no binding. */
10666 tmp = DECL_NAME (tmp);
10667 finish_goto_stmt (tmp);
10671 tmp = finish_asm_stmt
10672 (ASM_VOLATILE_P (t),
10673 RECUR (ASM_STRING (t)),
10674 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
10675 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
10676 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl));
10678 tree asm_expr = tmp;
10679 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
10680 asm_expr = TREE_OPERAND (asm_expr, 0);
10681 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
10688 stmt = begin_try_block ();
10689 RECUR (TRY_STMTS (t));
10690 finish_cleanup_try_block (stmt);
10691 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
10695 tree compound_stmt = NULL_TREE;
10697 if (FN_TRY_BLOCK_P (t))
10698 stmt = begin_function_try_block (&compound_stmt);
10700 stmt = begin_try_block ();
10702 RECUR (TRY_STMTS (t));
10704 if (FN_TRY_BLOCK_P (t))
10705 finish_function_try_block (stmt);
10707 finish_try_block (stmt);
10709 RECUR (TRY_HANDLERS (t));
10710 if (FN_TRY_BLOCK_P (t))
10711 finish_function_handler_sequence (stmt, compound_stmt);
10713 finish_handler_sequence (stmt);
10719 tree decl = HANDLER_PARMS (t);
10723 decl = tsubst (decl, args, complain, in_decl);
10724 /* Prevent instantiate_decl from trying to instantiate
10725 this variable. We've already done all that needs to be
10727 if (decl != error_mark_node)
10728 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
10730 stmt = begin_handler ();
10731 finish_handler_parms (decl, stmt);
10732 RECUR (HANDLER_BODY (t));
10733 finish_handler (stmt);
10738 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
10741 case STATIC_ASSERT:
10744 tsubst_expr (STATIC_ASSERT_CONDITION (t),
10747 /*integral_constant_expression_p=*/true);
10748 finish_static_assert (condition,
10749 STATIC_ASSERT_MESSAGE (t),
10750 STATIC_ASSERT_SOURCE_LOCATION (t),
10751 /*member_p=*/false);
10756 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
10757 args, complain, in_decl);
10758 stmt = begin_omp_parallel ();
10759 RECUR (OMP_PARALLEL_BODY (t));
10760 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
10761 = OMP_PARALLEL_COMBINED (t);
10765 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
10766 args, complain, in_decl);
10767 stmt = begin_omp_task ();
10768 RECUR (OMP_TASK_BODY (t));
10769 finish_omp_task (tmp, stmt);
10774 tree clauses, body, pre_body;
10775 tree declv, initv, condv, incrv;
10778 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
10779 args, complain, in_decl);
10780 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
10781 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
10782 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
10783 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
10785 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
10786 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
10787 &clauses, args, complain, in_decl,
10788 integral_constant_expression_p);
10790 stmt = begin_omp_structured_block ();
10792 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
10793 if (TREE_VEC_ELT (initv, i) == NULL
10794 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
10795 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
10796 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
10798 tree init = RECUR (TREE_VEC_ELT (initv, i));
10799 gcc_assert (init == TREE_VEC_ELT (declv, i));
10800 TREE_VEC_ELT (initv, i) = NULL_TREE;
10804 tree decl_expr = TREE_VEC_ELT (initv, i);
10805 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
10806 gcc_assert (init != NULL);
10807 TREE_VEC_ELT (initv, i) = RECUR (init);
10808 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
10810 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
10813 pre_body = push_stmt_list ();
10814 RECUR (OMP_FOR_PRE_BODY (t));
10815 pre_body = pop_stmt_list (pre_body);
10817 body = push_stmt_list ();
10818 RECUR (OMP_FOR_BODY (t));
10819 body = pop_stmt_list (body);
10821 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
10822 body, pre_body, clauses);
10824 add_stmt (finish_omp_structured_block (stmt));
10830 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
10831 stmt = push_stmt_list ();
10832 RECUR (OMP_BODY (t));
10833 stmt = pop_stmt_list (stmt);
10836 OMP_BODY (t) = stmt;
10837 OMP_CLAUSES (t) = tmp;
10845 stmt = push_stmt_list ();
10846 RECUR (OMP_BODY (t));
10847 stmt = pop_stmt_list (stmt);
10850 OMP_BODY (t) = stmt;
10855 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
10857 tree op1 = TREE_OPERAND (t, 1);
10858 tree lhs = RECUR (TREE_OPERAND (op1, 0));
10859 tree rhs = RECUR (TREE_OPERAND (op1, 1));
10860 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
10864 case EXPR_PACK_EXPANSION:
10865 error ("invalid use of pack expansion expression");
10866 return error_mark_node;
10868 case NONTYPE_ARGUMENT_PACK:
10869 error ("use %<...%> to expand argument pack");
10870 return error_mark_node;
10873 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
10875 return tsubst_copy_and_build (t, args, complain, in_decl,
10876 /*function_p=*/false,
10877 integral_constant_expression_p);
10884 /* T is a postfix-expression that is not being used in a function
10885 call. Return the substituted version of T. */
10888 tsubst_non_call_postfix_expression (tree t, tree args,
10889 tsubst_flags_t complain,
10892 if (TREE_CODE (t) == SCOPE_REF)
10893 t = tsubst_qualified_id (t, args, complain, in_decl,
10894 /*done=*/false, /*address_p=*/false);
10896 t = tsubst_copy_and_build (t, args, complain, in_decl,
10897 /*function_p=*/false,
10898 /*integral_constant_expression_p=*/false);
10903 /* Like tsubst but deals with expressions and performs semantic
10904 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
10907 tsubst_copy_and_build (tree t,
10909 tsubst_flags_t complain,
10912 bool integral_constant_expression_p)
10914 #define RECUR(NODE) \
10915 tsubst_copy_and_build (NODE, args, complain, in_decl, \
10916 /*function_p=*/false, \
10917 integral_constant_expression_p)
10921 if (t == NULL_TREE || t == error_mark_node)
10924 switch (TREE_CODE (t))
10928 /* Fall through. */
10929 case IDENTIFIER_NODE:
10933 bool non_integral_constant_expression_p;
10934 const char *error_msg;
10936 if (IDENTIFIER_TYPENAME_P (t))
10938 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10939 t = mangle_conv_op_name_for_type (new_type);
10942 /* Look up the name. */
10943 decl = lookup_name (t);
10945 /* By convention, expressions use ERROR_MARK_NODE to indicate
10946 failure, not NULL_TREE. */
10947 if (decl == NULL_TREE)
10948 decl = error_mark_node;
10950 decl = finish_id_expression (t, decl, NULL_TREE,
10952 integral_constant_expression_p,
10953 /*allow_non_integral_constant_expression_p=*/false,
10954 &non_integral_constant_expression_p,
10955 /*template_p=*/false,
10957 /*address_p=*/false,
10958 /*template_arg_p=*/false,
10963 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
10964 decl = unqualified_name_lookup_error (decl);
10968 case TEMPLATE_ID_EXPR:
10971 tree templ = RECUR (TREE_OPERAND (t, 0));
10972 tree targs = TREE_OPERAND (t, 1);
10975 targs = tsubst_template_args (targs, args, complain, in_decl);
10977 if (TREE_CODE (templ) == COMPONENT_REF)
10979 object = TREE_OPERAND (templ, 0);
10980 templ = TREE_OPERAND (templ, 1);
10983 object = NULL_TREE;
10984 templ = lookup_template_function (templ, targs);
10987 return build3 (COMPONENT_REF, TREE_TYPE (templ),
10988 object, templ, NULL_TREE);
10990 return baselink_for_fns (templ);
10995 tree r = RECUR (TREE_OPERAND (t, 0));
10997 if (REFERENCE_REF_P (t))
10999 /* A type conversion to reference type will be enclosed in
11000 such an indirect ref, but the substitution of the cast
11001 will have also added such an indirect ref. */
11002 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
11003 r = convert_from_reference (r);
11006 r = build_x_indirect_ref (r, "unary *", complain);
11012 (tsubst (TREE_TYPE (t), args, complain, in_decl),
11013 RECUR (TREE_OPERAND (t, 0)));
11016 case REINTERPRET_CAST_EXPR:
11017 case CONST_CAST_EXPR:
11018 case DYNAMIC_CAST_EXPR:
11019 case STATIC_CAST_EXPR:
11024 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11025 if (integral_constant_expression_p
11026 && !cast_valid_in_integral_constant_expression_p (type))
11028 if (complain & tf_error)
11029 error ("a cast to a type other than an integral or "
11030 "enumeration type cannot appear in a constant-expression");
11031 return error_mark_node;
11034 op = RECUR (TREE_OPERAND (t, 0));
11036 switch (TREE_CODE (t))
11039 return build_functional_cast (type, op, complain);
11040 case REINTERPRET_CAST_EXPR:
11041 return build_reinterpret_cast (type, op, complain);
11042 case CONST_CAST_EXPR:
11043 return build_const_cast (type, op, complain);
11044 case DYNAMIC_CAST_EXPR:
11045 return build_dynamic_cast (type, op, complain);
11046 case STATIC_CAST_EXPR:
11047 return build_static_cast (type, op, complain);
11049 gcc_unreachable ();
11053 case POSTDECREMENT_EXPR:
11054 case POSTINCREMENT_EXPR:
11055 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11056 args, complain, in_decl);
11057 return build_x_unary_op (TREE_CODE (t), op1, complain);
11059 case PREDECREMENT_EXPR:
11060 case PREINCREMENT_EXPR:
11064 case TRUTH_NOT_EXPR:
11065 case UNARY_PLUS_EXPR: /* Unary + */
11066 case REALPART_EXPR:
11067 case IMAGPART_EXPR:
11068 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
11072 op1 = TREE_OPERAND (t, 0);
11073 if (TREE_CODE (op1) == SCOPE_REF)
11074 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
11075 /*done=*/true, /*address_p=*/true);
11077 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
11079 if (TREE_CODE (op1) == LABEL_DECL)
11080 return finish_label_address_expr (DECL_NAME (op1),
11081 EXPR_LOCATION (op1));
11082 return build_x_unary_op (ADDR_EXPR, op1, complain);
11087 case TRUNC_DIV_EXPR:
11088 case CEIL_DIV_EXPR:
11089 case FLOOR_DIV_EXPR:
11090 case ROUND_DIV_EXPR:
11091 case EXACT_DIV_EXPR:
11095 case TRUNC_MOD_EXPR:
11096 case FLOOR_MOD_EXPR:
11097 case TRUTH_ANDIF_EXPR:
11098 case TRUTH_ORIF_EXPR:
11099 case TRUTH_AND_EXPR:
11100 case TRUTH_OR_EXPR:
11115 return build_x_binary_op
11117 RECUR (TREE_OPERAND (t, 0)),
11118 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
11120 : TREE_CODE (TREE_OPERAND (t, 0))),
11121 RECUR (TREE_OPERAND (t, 1)),
11122 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
11124 : TREE_CODE (TREE_OPERAND (t, 1))),
11125 /*overloaded_p=*/NULL,
11129 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
11130 /*address_p=*/false);
11132 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11133 args, complain, in_decl);
11134 return build_x_binary_op (ARRAY_REF, op1,
11135 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
11137 : TREE_CODE (TREE_OPERAND (t, 0))),
11138 RECUR (TREE_OPERAND (t, 1)),
11139 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
11141 : TREE_CODE (TREE_OPERAND (t, 1))),
11142 /*overloaded_p=*/NULL,
11146 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11147 return tsubst_copy (t, args, complain, in_decl);
11151 op1 = TREE_OPERAND (t, 0);
11154 /* When there are no ARGS, we are trying to evaluate a
11155 non-dependent expression from the parser. Trying to do
11156 the substitutions may not work. */
11158 op1 = TREE_TYPE (op1);
11163 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
11164 /*function_p=*/false,
11165 /*integral_constant_expression_p=*/false);
11169 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
11170 complain & tf_error);
11172 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
11173 complain & tf_error);
11177 tree r = build_x_modify_expr
11178 (RECUR (TREE_OPERAND (t, 0)),
11179 TREE_CODE (TREE_OPERAND (t, 1)),
11180 RECUR (TREE_OPERAND (t, 2)),
11182 /* TREE_NO_WARNING must be set if either the expression was
11183 parenthesized or it uses an operator such as >>= rather
11184 than plain assignment. In the former case, it was already
11185 set and must be copied. In the latter case,
11186 build_x_modify_expr sets it and it must not be reset
11188 if (TREE_NO_WARNING (t))
11189 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11194 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11195 args, complain, in_decl);
11196 /* Remember that there was a reference to this entity. */
11199 return build_x_arrow (op1);
11203 tree init = RECUR (TREE_OPERAND (t, 3));
11205 if (TREE_OPERAND (t, 3) && !init)
11206 /* If there was an initializer in the original tree, but
11207 it instantiated to an empty list, then we should pass on
11208 VOID_ZERO_NODE to tell build_new that it was an empty
11209 initializer () rather than no initializer. This can only
11210 happen when the initializer is a pack expansion whose
11211 parameter packs are of length zero. */
11212 init = void_zero_node;
11215 (RECUR (TREE_OPERAND (t, 0)),
11216 RECUR (TREE_OPERAND (t, 1)),
11217 RECUR (TREE_OPERAND (t, 2)),
11219 NEW_EXPR_USE_GLOBAL (t),
11224 return delete_sanity
11225 (RECUR (TREE_OPERAND (t, 0)),
11226 RECUR (TREE_OPERAND (t, 1)),
11227 DELETE_EXPR_USE_VEC (t),
11228 DELETE_EXPR_USE_GLOBAL (t));
11230 case COMPOUND_EXPR:
11231 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
11232 RECUR (TREE_OPERAND (t, 1)),
11242 function = CALL_EXPR_FN (t);
11243 /* When we parsed the expression, we determined whether or
11244 not Koenig lookup should be performed. */
11245 koenig_p = KOENIG_LOOKUP_P (t);
11246 if (TREE_CODE (function) == SCOPE_REF)
11248 qualified_p = true;
11249 function = tsubst_qualified_id (function, args, complain, in_decl,
11251 /*address_p=*/false);
11255 if (TREE_CODE (function) == COMPONENT_REF)
11257 tree op = TREE_OPERAND (function, 1);
11259 qualified_p = (TREE_CODE (op) == SCOPE_REF
11260 || (BASELINK_P (op)
11261 && BASELINK_QUALIFIED_P (op)));
11264 qualified_p = false;
11266 function = tsubst_copy_and_build (function, args, complain,
11269 integral_constant_expression_p);
11271 if (BASELINK_P (function))
11272 qualified_p = true;
11275 /* FIXME: Rewrite this so as not to construct an arglist. */
11276 call_args = RECUR (CALL_EXPR_ARGS (t));
11278 /* We do not perform argument-dependent lookup if normal
11279 lookup finds a non-function, in accordance with the
11280 expected resolution of DR 218. */
11282 && ((is_overloaded_fn (function)
11283 /* If lookup found a member function, the Koenig lookup is
11284 not appropriate, even if an unqualified-name was used
11285 to denote the function. */
11286 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
11287 || TREE_CODE (function) == IDENTIFIER_NODE))
11288 function = perform_koenig_lookup (function, call_args);
11290 if (TREE_CODE (function) == IDENTIFIER_NODE)
11292 unqualified_name_lookup_error (function);
11293 return error_mark_node;
11296 /* Remember that there was a reference to this entity. */
11297 if (DECL_P (function))
11298 mark_used (function);
11300 if (TREE_CODE (function) == OFFSET_REF)
11301 return build_offset_ref_call_from_tree (function, call_args);
11302 if (TREE_CODE (function) == COMPONENT_REF)
11304 if (!BASELINK_P (TREE_OPERAND (function, 1)))
11305 return finish_call_expr (function, call_args,
11306 /*disallow_virtual=*/false,
11307 /*koenig_p=*/false,
11310 return (build_new_method_call
11311 (TREE_OPERAND (function, 0),
11312 TREE_OPERAND (function, 1),
11313 call_args, NULL_TREE,
11314 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
11318 return finish_call_expr (function, call_args,
11319 /*disallow_virtual=*/qualified_p,
11325 return build_x_conditional_expr
11326 (RECUR (TREE_OPERAND (t, 0)),
11327 RECUR (TREE_OPERAND (t, 1)),
11328 RECUR (TREE_OPERAND (t, 2)),
11331 case PSEUDO_DTOR_EXPR:
11332 return finish_pseudo_destructor_expr
11333 (RECUR (TREE_OPERAND (t, 0)),
11334 RECUR (TREE_OPERAND (t, 1)),
11335 RECUR (TREE_OPERAND (t, 2)));
11339 tree purpose, value, chain;
11341 if (t == void_list_node)
11344 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
11345 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
11347 /* We have pack expansions, so expand those and
11348 create a new list out of it. */
11349 tree purposevec = NULL_TREE;
11350 tree valuevec = NULL_TREE;
11354 /* Expand the argument expressions. */
11355 if (TREE_PURPOSE (t))
11356 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
11357 complain, in_decl);
11358 if (TREE_VALUE (t))
11359 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
11360 complain, in_decl);
11362 /* Build the rest of the list. */
11363 chain = TREE_CHAIN (t);
11364 if (chain && chain != void_type_node)
11365 chain = RECUR (chain);
11367 /* Determine the number of arguments. */
11368 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
11370 len = TREE_VEC_LENGTH (purposevec);
11371 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
11373 else if (TREE_CODE (valuevec) == TREE_VEC)
11374 len = TREE_VEC_LENGTH (valuevec);
11377 /* Since we only performed a partial substitution into
11378 the argument pack, we only return a single list
11380 if (purposevec == TREE_PURPOSE (t)
11381 && valuevec == TREE_VALUE (t)
11382 && chain == TREE_CHAIN (t))
11385 return tree_cons (purposevec, valuevec, chain);
11388 /* Convert the argument vectors into a TREE_LIST */
11392 /* Grab the Ith values. */
11394 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
11397 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
11400 /* Build the list (backwards). */
11401 chain = tree_cons (purpose, value, chain);
11407 purpose = TREE_PURPOSE (t);
11409 purpose = RECUR (purpose);
11410 value = TREE_VALUE (t);
11412 value = RECUR (value);
11413 chain = TREE_CHAIN (t);
11414 if (chain && chain != void_type_node)
11415 chain = RECUR (chain);
11416 if (purpose == TREE_PURPOSE (t)
11417 && value == TREE_VALUE (t)
11418 && chain == TREE_CHAIN (t))
11420 return tree_cons (purpose, value, chain);
11423 case COMPONENT_REF:
11429 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11430 args, complain, in_decl);
11431 /* Remember that there was a reference to this entity. */
11432 if (DECL_P (object))
11433 mark_used (object);
11434 object_type = TREE_TYPE (object);
11436 member = TREE_OPERAND (t, 1);
11437 if (BASELINK_P (member))
11438 member = tsubst_baselink (member,
11439 non_reference (TREE_TYPE (object)),
11440 args, complain, in_decl);
11442 member = tsubst_copy (member, args, complain, in_decl);
11443 if (member == error_mark_node)
11444 return error_mark_node;
11446 if (object_type && !CLASS_TYPE_P (object_type))
11448 if (SCALAR_TYPE_P (object_type))
11450 tree s = NULL_TREE;
11451 tree dtor = member;
11453 if (TREE_CODE (dtor) == SCOPE_REF)
11455 s = TREE_OPERAND (dtor, 0);
11456 dtor = TREE_OPERAND (dtor, 1);
11458 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
11460 dtor = TREE_OPERAND (dtor, 0);
11462 return finish_pseudo_destructor_expr (object, s, dtor);
11466 else if (TREE_CODE (member) == SCOPE_REF
11467 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
11472 /* Lookup the template functions now that we know what the
11474 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
11475 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
11476 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
11477 /*is_type_p=*/false,
11478 /*complain=*/false);
11479 if (BASELINK_P (member))
11481 BASELINK_FUNCTIONS (member)
11482 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
11484 member = (adjust_result_of_qualified_name_lookup
11485 (member, BINFO_TYPE (BASELINK_BINFO (member)),
11490 qualified_name_lookup_error (object_type, tmpl, member,
11492 return error_mark_node;
11495 else if (TREE_CODE (member) == SCOPE_REF
11496 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
11497 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
11499 if (complain & tf_error)
11501 if (TYPE_P (TREE_OPERAND (member, 0)))
11502 error ("%qT is not a class or namespace",
11503 TREE_OPERAND (member, 0));
11505 error ("%qD is not a class or namespace",
11506 TREE_OPERAND (member, 0));
11508 return error_mark_node;
11510 else if (TREE_CODE (member) == FIELD_DECL)
11511 return finish_non_static_data_member (member, object, NULL_TREE);
11513 return finish_class_member_access_expr (object, member,
11514 /*template_p=*/false,
11520 (RECUR (TREE_OPERAND (t, 0)));
11524 VEC(constructor_elt,gc) *n;
11525 constructor_elt *ce;
11526 unsigned HOST_WIDE_INT idx;
11527 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11528 bool process_index_p;
11530 bool need_copy_p = false;
11533 if (type == error_mark_node)
11534 return error_mark_node;
11536 /* digest_init will do the wrong thing if we let it. */
11537 if (type && TYPE_PTRMEMFUNC_P (type))
11540 /* We do not want to process the index of aggregate
11541 initializers as they are identifier nodes which will be
11542 looked up by digest_init. */
11543 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
11545 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
11546 newlen = VEC_length (constructor_elt, n);
11547 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
11549 if (ce->index && process_index_p)
11550 ce->index = RECUR (ce->index);
11552 if (PACK_EXPANSION_P (ce->value))
11554 /* Substitute into the pack expansion. */
11555 ce->value = tsubst_pack_expansion (ce->value, args, complain,
11558 if (ce->value == error_mark_node)
11560 else if (TREE_VEC_LENGTH (ce->value) == 1)
11561 /* Just move the argument into place. */
11562 ce->value = TREE_VEC_ELT (ce->value, 0);
11565 /* Update the length of the final CONSTRUCTOR
11566 arguments vector, and note that we will need to
11568 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
11569 need_copy_p = true;
11573 ce->value = RECUR (ce->value);
11578 VEC(constructor_elt,gc) *old_n = n;
11580 n = VEC_alloc (constructor_elt, gc, newlen);
11581 for (idx = 0; VEC_iterate (constructor_elt, old_n, idx, ce);
11584 if (TREE_CODE (ce->value) == TREE_VEC)
11586 int i, len = TREE_VEC_LENGTH (ce->value);
11587 for (i = 0; i < len; ++i)
11588 CONSTRUCTOR_APPEND_ELT (n, 0,
11589 TREE_VEC_ELT (ce->value, i));
11592 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
11596 r = build_constructor (init_list_type_node, n);
11598 if (TREE_HAS_CONSTRUCTOR (t))
11599 return finish_compound_literal (type, r);
11606 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
11607 if (TYPE_P (operand_0))
11608 return get_typeid (operand_0);
11609 return build_typeid (operand_0);
11619 tree r = tsubst_copy (t, args, complain, in_decl);
11621 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
11622 /* If the original type was a reference, we'll be wrapped in
11623 the appropriate INDIRECT_REF. */
11624 r = convert_from_reference (r);
11629 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
11630 tsubst_copy (TREE_TYPE (t), args, complain,
11633 case OFFSETOF_EXPR:
11634 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
11638 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
11639 complain, in_decl);
11641 tree type2 = TRAIT_EXPR_TYPE2 (t);
11643 type2 = tsubst_copy (type2, args, complain, in_decl);
11645 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
11650 tree old_stmt_expr = cur_stmt_expr;
11651 tree stmt_expr = begin_stmt_expr ();
11653 cur_stmt_expr = stmt_expr;
11654 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
11655 integral_constant_expression_p);
11656 stmt_expr = finish_stmt_expr (stmt_expr, false);
11657 cur_stmt_expr = old_stmt_expr;
11663 t = tsubst_copy (t, args, complain, in_decl);
11664 /* As in finish_id_expression, we resolve enumeration constants
11665 to their underlying values. */
11666 if (TREE_CODE (t) == CONST_DECL)
11668 used_types_insert (TREE_TYPE (t));
11669 return DECL_INITIAL (t);
11674 /* Handle Objective-C++ constructs, if appropriate. */
11677 = objcp_tsubst_copy_and_build (t, args, complain,
11678 in_decl, /*function_p=*/false);
11682 return tsubst_copy (t, args, complain, in_decl);
11688 /* Verify that the instantiated ARGS are valid. For type arguments,
11689 make sure that the type's linkage is ok. For non-type arguments,
11690 make sure they are constants if they are integral or enumerations.
11691 Emit an error under control of COMPLAIN, and return TRUE on error. */
11694 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
11696 int ix, len = DECL_NTPARMS (tmpl);
11697 bool result = false;
11699 for (ix = 0; ix != len; ix++)
11701 tree t = TREE_VEC_ELT (args, ix);
11705 /* [basic.link]: A name with no linkage (notably, the name
11706 of a class or enumeration declared in a local scope)
11707 shall not be used to declare an entity with linkage.
11708 This implies that names with no linkage cannot be used as
11709 template arguments. */
11710 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
11714 /* DR 488 makes use of a type with no linkage cause
11715 type deduction to fail. */
11716 if (complain & tf_error)
11718 if (TYPE_ANONYMOUS_P (nt))
11719 error ("%qT is/uses anonymous type", t);
11721 error ("template argument for %qD uses local type %qT",
11726 /* In order to avoid all sorts of complications, we do not
11727 allow variably-modified types as template arguments. */
11728 else if (variably_modified_type_p (t, NULL_TREE))
11730 if (complain & tf_error)
11731 error ("%qT is a variably modified type", t);
11735 /* A non-type argument of integral or enumerated type must be a
11737 else if (TREE_TYPE (t)
11738 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
11739 && !TREE_CONSTANT (t))
11741 if (complain & tf_error)
11742 error ("integral expression %qE is not constant", t);
11746 if (result && (complain & tf_error))
11747 error (" trying to instantiate %qD", tmpl);
11751 /* Instantiate the indicated variable or function template TMPL with
11752 the template arguments in TARG_PTR. */
11755 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
11760 HOST_WIDE_INT saved_processing_template_decl;
11762 if (tmpl == error_mark_node)
11763 return error_mark_node;
11765 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
11767 /* If this function is a clone, handle it specially. */
11768 if (DECL_CLONED_FUNCTION_P (tmpl))
11773 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
11775 if (spec == error_mark_node)
11776 return error_mark_node;
11778 /* Look for the clone. */
11779 FOR_EACH_CLONE (clone, spec)
11780 if (DECL_NAME (clone) == DECL_NAME (tmpl))
11782 /* We should always have found the clone by now. */
11783 gcc_unreachable ();
11787 /* Check to see if we already have this specialization. */
11788 spec = retrieve_specialization (tmpl, targ_ptr,
11789 /*class_specializations_p=*/false);
11790 if (spec != NULL_TREE)
11793 gen_tmpl = most_general_template (tmpl);
11794 if (tmpl != gen_tmpl)
11796 /* The TMPL is a partial instantiation. To get a full set of
11797 arguments we must add the arguments used to perform the
11798 partial instantiation. */
11799 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
11802 /* Check to see if we already have this specialization. */
11803 spec = retrieve_specialization (gen_tmpl, targ_ptr,
11804 /*class_specializations_p=*/false);
11805 if (spec != NULL_TREE)
11809 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
11811 return error_mark_node;
11813 /* We are building a FUNCTION_DECL, during which the access of its
11814 parameters and return types have to be checked. However this
11815 FUNCTION_DECL which is the desired context for access checking
11816 is not built yet. We solve this chicken-and-egg problem by
11817 deferring all checks until we have the FUNCTION_DECL. */
11818 push_deferring_access_checks (dk_deferred);
11820 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
11821 (because, for example, we have encountered a non-dependent
11822 function call in the body of a template function and must now
11823 determine which of several overloaded functions will be called),
11824 within the instantiation itself we are not processing a
11826 saved_processing_template_decl = processing_template_decl;
11827 processing_template_decl = 0;
11828 /* Substitute template parameters to obtain the specialization. */
11829 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
11830 targ_ptr, complain, gen_tmpl);
11831 processing_template_decl = saved_processing_template_decl;
11832 if (fndecl == error_mark_node)
11833 return error_mark_node;
11835 /* Now we know the specialization, compute access previously
11837 push_access_scope (fndecl);
11838 perform_deferred_access_checks ();
11839 pop_access_scope (fndecl);
11840 pop_deferring_access_checks ();
11842 /* The DECL_TI_TEMPLATE should always be the immediate parent
11843 template, not the most general template. */
11844 DECL_TI_TEMPLATE (fndecl) = tmpl;
11846 /* If we've just instantiated the main entry point for a function,
11847 instantiate all the alternate entry points as well. We do this
11848 by cloning the instantiation of the main entry point, not by
11849 instantiating the template clones. */
11850 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
11851 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
11856 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
11857 arguments that are being used when calling it. TARGS is a vector
11858 into which the deduced template arguments are placed.
11860 Return zero for success, 2 for an incomplete match that doesn't resolve
11861 all the types, and 1 for complete failure. An error message will be
11862 printed only for an incomplete match.
11864 If FN is a conversion operator, or we are trying to produce a specific
11865 specialization, RETURN_TYPE is the return type desired.
11867 The EXPLICIT_TARGS are explicit template arguments provided via a
11870 The parameter STRICT is one of:
11873 We are deducing arguments for a function call, as in
11874 [temp.deduct.call].
11877 We are deducing arguments for a conversion function, as in
11878 [temp.deduct.conv].
11881 We are deducing arguments when doing an explicit instantiation
11882 as in [temp.explicit], when determining an explicit specialization
11883 as in [temp.expl.spec], or when taking the address of a function
11884 template, as in [temp.deduct.funcaddr]. */
11887 fn_type_unification (tree fn,
11888 tree explicit_targs,
11892 unification_kind_t strict,
11898 bool incomplete_argument_packs_p = false;
11900 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
11902 fntype = TREE_TYPE (fn);
11903 if (explicit_targs)
11907 The specified template arguments must match the template
11908 parameters in kind (i.e., type, nontype, template), and there
11909 must not be more arguments than there are parameters;
11910 otherwise type deduction fails.
11912 Nontype arguments must match the types of the corresponding
11913 nontype template parameters, or must be convertible to the
11914 types of the corresponding nontype parameters as specified in
11915 _temp.arg.nontype_, otherwise type deduction fails.
11917 All references in the function type of the function template
11918 to the corresponding template parameters are replaced by the
11919 specified template argument values. If a substitution in a
11920 template parameter or in the function type of the function
11921 template results in an invalid type, type deduction fails. */
11922 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
11923 int i, len = TREE_VEC_LENGTH (tparms);
11924 tree converted_args;
11925 bool incomplete = false;
11927 if (explicit_targs == error_mark_node)
11931 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
11932 /*require_all_args=*/false,
11933 /*use_default_args=*/false));
11934 if (converted_args == error_mark_node)
11937 /* Substitute the explicit args into the function type. This is
11938 necessary so that, for instance, explicitly declared function
11939 arguments can match null pointed constants. If we were given
11940 an incomplete set of explicit args, we must not do semantic
11941 processing during substitution as we could create partial
11943 for (i = 0; i < len; i++)
11945 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
11946 bool parameter_pack = false;
11948 /* Dig out the actual parm. */
11949 if (TREE_CODE (parm) == TYPE_DECL
11950 || TREE_CODE (parm) == TEMPLATE_DECL)
11952 parm = TREE_TYPE (parm);
11953 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
11955 else if (TREE_CODE (parm) == PARM_DECL)
11957 parm = DECL_INITIAL (parm);
11958 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
11961 if (parameter_pack)
11965 template_parm_level_and_index (parm, &level, &idx);
11967 /* Mark the argument pack as "incomplete". We could
11968 still deduce more arguments during unification. */
11969 targ = TMPL_ARG (converted_args, level, idx);
11972 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
11973 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
11974 = ARGUMENT_PACK_ARGS (targ);
11977 /* We have some incomplete argument packs. */
11978 incomplete_argument_packs_p = true;
11982 if (incomplete_argument_packs_p)
11983 /* Any substitution is guaranteed to be incomplete if there
11984 are incomplete argument packs, because we can still deduce
11988 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
11990 processing_template_decl += incomplete;
11991 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
11992 processing_template_decl -= incomplete;
11994 if (fntype == error_mark_node)
11997 /* Place the explicitly specified arguments in TARGS. */
11998 for (i = NUM_TMPL_ARGS (converted_args); i--;)
11999 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
12002 /* Never do unification on the 'this' parameter. */
12003 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
12007 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
12008 args = tree_cons (NULL_TREE, return_type, args);
12011 /* We allow incomplete unification without an error message here
12012 because the standard doesn't seem to explicitly prohibit it. Our
12013 callers must be ready to deal with unification failures in any
12015 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
12016 targs, parms, args, /*subr=*/0,
12019 if (result == 0 && incomplete_argument_packs_p)
12021 int i, len = NUM_TMPL_ARGS (targs);
12023 /* Clear the "incomplete" flags on all argument packs. */
12024 for (i = 0; i < len; i++)
12026 tree arg = TREE_VEC_ELT (targs, i);
12027 if (ARGUMENT_PACK_P (arg))
12029 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
12030 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
12035 /* Now that we have bindings for all of the template arguments,
12036 ensure that the arguments deduced for the template template
12037 parameters have compatible template parameter lists. We cannot
12038 check this property before we have deduced all template
12039 arguments, because the template parameter types of a template
12040 template parameter might depend on prior template parameters
12041 deduced after the template template parameter. The following
12042 ill-formed example illustrates this issue:
12044 template<typename T, template<T> class C> void f(C<5>, T);
12046 template<int N> struct X {};
12049 f(X<5>(), 5l); // error: template argument deduction fails
12052 The template parameter list of 'C' depends on the template type
12053 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
12054 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
12055 time that we deduce 'C'. */
12057 && !template_template_parm_bindings_ok_p
12058 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
12062 /* All is well so far. Now, check:
12066 When all template arguments have been deduced, all uses of
12067 template parameters in nondeduced contexts are replaced with
12068 the corresponding deduced argument values. If the
12069 substitution results in an invalid type, as described above,
12070 type deduction fails. */
12071 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
12072 == error_mark_node)
12078 /* Adjust types before performing type deduction, as described in
12079 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
12080 sections are symmetric. PARM is the type of a function parameter
12081 or the return type of the conversion function. ARG is the type of
12082 the argument passed to the call, or the type of the value
12083 initialized with the result of the conversion function.
12084 ARG_EXPR is the original argument expression, which may be null. */
12087 maybe_adjust_types_for_deduction (unification_kind_t strict,
12101 /* Swap PARM and ARG throughout the remainder of this
12102 function; the handling is precisely symmetric since PARM
12103 will initialize ARG rather than vice versa. */
12111 /* There is nothing to do in this case. */
12115 gcc_unreachable ();
12118 if (TREE_CODE (*parm) != REFERENCE_TYPE)
12120 /* [temp.deduct.call]
12122 If P is not a reference type:
12124 --If A is an array type, the pointer type produced by the
12125 array-to-pointer standard conversion (_conv.array_) is
12126 used in place of A for type deduction; otherwise,
12128 --If A is a function type, the pointer type produced by
12129 the function-to-pointer standard conversion
12130 (_conv.func_) is used in place of A for type deduction;
12133 --If A is a cv-qualified type, the top level
12134 cv-qualifiers of A's type are ignored for type
12136 if (TREE_CODE (*arg) == ARRAY_TYPE)
12137 *arg = build_pointer_type (TREE_TYPE (*arg));
12138 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
12139 *arg = build_pointer_type (*arg);
12141 *arg = TYPE_MAIN_VARIANT (*arg);
12144 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
12145 of the form T&&, where T is a template parameter, and the argument
12146 is an lvalue, T is deduced as A& */
12147 if (TREE_CODE (*parm) == REFERENCE_TYPE
12148 && TYPE_REF_IS_RVALUE (*parm)
12149 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
12150 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
12151 && arg_expr && real_lvalue_p (arg_expr))
12152 *arg = build_reference_type (*arg);
12154 /* [temp.deduct.call]
12156 If P is a cv-qualified type, the top level cv-qualifiers
12157 of P's type are ignored for type deduction. If P is a
12158 reference type, the type referred to by P is used for
12160 *parm = TYPE_MAIN_VARIANT (*parm);
12161 if (TREE_CODE (*parm) == REFERENCE_TYPE)
12163 *parm = TREE_TYPE (*parm);
12164 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
12167 /* DR 322. For conversion deduction, remove a reference type on parm
12168 too (which has been swapped into ARG). */
12169 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
12170 *arg = TREE_TYPE (*arg);
12175 /* Most parms like fn_type_unification.
12177 If SUBR is 1, we're being called recursively (to unify the
12178 arguments of a function or method parameter of a function
12182 type_unification_real (tree tparms,
12187 unification_kind_t strict,
12190 tree parm, arg, arg_expr;
12192 int ntparms = TREE_VEC_LENGTH (tparms);
12194 int saw_undeduced = 0;
12197 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
12198 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
12199 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
12200 gcc_assert (ntparms > 0);
12205 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
12206 | UNIFY_ALLOW_DERIVED);
12210 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
12214 sub_strict = UNIFY_ALLOW_NONE;
12218 gcc_unreachable ();
12225 while (parms && parms != void_list_node
12226 && args && args != void_list_node)
12228 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
12231 parm = TREE_VALUE (parms);
12232 parms = TREE_CHAIN (parms);
12233 arg = TREE_VALUE (args);
12234 args = TREE_CHAIN (args);
12237 if (arg == error_mark_node)
12239 if (arg == unknown_type_node)
12240 /* We can't deduce anything from this, but we might get all the
12241 template args from other function args. */
12244 /* Conversions will be performed on a function argument that
12245 corresponds with a function parameter that contains only
12246 non-deducible template parameters and explicitly specified
12247 template parameters. */
12248 if (!uses_template_parms (parm))
12253 type = TREE_TYPE (arg);
12257 if (same_type_p (parm, type))
12259 if (strict != DEDUCE_EXACT
12260 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
12269 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
12270 if (type_unknown_p (arg))
12272 /* [temp.deduct.type]
12274 A template-argument can be deduced from a pointer to
12275 function or pointer to member function argument if
12276 the set of overloaded functions does not contain
12277 function templates and at most one of a set of
12278 overloaded functions provides a unique match. */
12279 if (resolve_overloaded_unification
12280 (tparms, targs, parm, arg, strict, sub_strict))
12286 arg = unlowered_expr_type (arg);
12287 if (arg == error_mark_node)
12292 int arg_strict = sub_strict;
12295 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
12298 if (arg == init_list_type_node && arg_expr)
12300 if (unify (tparms, targs, parm, arg, arg_strict))
12307 && parms != void_list_node
12308 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
12310 /* Unify the remaining arguments with the pack expansion type. */
12312 tree parmvec = make_tree_vec (1);
12316 /* Count the number of arguments that remain. */
12317 for (t = args; t && t != void_list_node; t = TREE_CHAIN (t))
12320 /* Allocate a TREE_VEC and copy in all of the arguments */
12321 argvec = make_tree_vec (len);
12322 for (i = 0; args && args != void_list_node; args = TREE_CHAIN (args))
12324 TREE_VEC_ELT (argvec, i) = TREE_VALUE (args);
12328 /* Copy the parameter into parmvec. */
12329 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
12330 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
12331 /*call_args_p=*/true, /*subr=*/subr))
12334 /* Advance to the end of the list of parameters. */
12335 parms = TREE_CHAIN (parms);
12338 /* Fail if we've reached the end of the parm list, and more args
12339 are present, and the parm list isn't variadic. */
12340 if (args && args != void_list_node && parms == void_list_node)
12342 /* Fail if parms are left and they don't have default values. */
12343 if (parms && parms != void_list_node
12344 && TREE_PURPOSE (parms) == NULL_TREE)
12348 for (i = 0; i < ntparms; i++)
12349 if (!TREE_VEC_ELT (targs, i))
12353 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
12356 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
12358 /* If this is an undeduced nontype parameter that depends on
12359 a type parameter, try another pass; its type may have been
12360 deduced from a later argument than the one from which
12361 this parameter can be deduced. */
12362 if (TREE_CODE (tparm) == PARM_DECL
12363 && uses_template_parms (TREE_TYPE (tparm))
12364 && !saw_undeduced++)
12367 /* Core issue #226 (C++0x) [temp.deduct]:
12369 If a template argument has not been deduced, its
12370 default template argument, if any, is used.
12372 When we are in C++98 mode, TREE_PURPOSE will either
12373 be NULL_TREE or ERROR_MARK_NODE, so we do not need
12374 to explicitly check cxx_dialect here. */
12375 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
12377 tree arg = tsubst (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)),
12378 targs, tf_none, NULL_TREE);
12379 if (arg == error_mark_node)
12383 TREE_VEC_ELT (targs, i) = arg;
12388 /* If the type parameter is a parameter pack, then it will
12389 be deduced to an empty parameter pack. */
12390 if (template_parameter_pack_p (tparm))
12394 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
12396 arg = make_node (NONTYPE_ARGUMENT_PACK);
12397 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
12398 TREE_CONSTANT (arg) = 1;
12401 arg = make_node (TYPE_ARGUMENT_PACK);
12403 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
12405 TREE_VEC_ELT (targs, i) = arg;
12415 /* Subroutine of type_unification_real. Args are like the variables
12416 at the call site. ARG is an overloaded function (or template-id);
12417 we try deducing template args from each of the overloads, and if
12418 only one succeeds, we go with that. Modifies TARGS and returns
12419 true on success. */
12422 resolve_overloaded_unification (tree tparms,
12426 unification_kind_t strict,
12429 tree tempargs = copy_node (targs);
12433 if (TREE_CODE (arg) == ADDR_EXPR)
12435 arg = TREE_OPERAND (arg, 0);
12441 if (TREE_CODE (arg) == COMPONENT_REF)
12442 /* Handle `&x' where `x' is some static or non-static member
12444 arg = TREE_OPERAND (arg, 1);
12446 if (TREE_CODE (arg) == OFFSET_REF)
12447 arg = TREE_OPERAND (arg, 1);
12449 /* Strip baselink information. */
12450 if (BASELINK_P (arg))
12451 arg = BASELINK_FUNCTIONS (arg);
12453 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
12455 /* If we got some explicit template args, we need to plug them into
12456 the affected templates before we try to unify, in case the
12457 explicit args will completely resolve the templates in question. */
12459 tree expl_subargs = TREE_OPERAND (arg, 1);
12460 arg = TREE_OPERAND (arg, 0);
12462 for (; arg; arg = OVL_NEXT (arg))
12464 tree fn = OVL_CURRENT (arg);
12465 tree subargs, elem;
12467 if (TREE_CODE (fn) != TEMPLATE_DECL)
12470 ++processing_template_decl;
12471 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
12472 expl_subargs, /*check_ret=*/false);
12475 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
12476 good += try_one_overload (tparms, targs, tempargs, parm,
12477 elem, strict, sub_strict, addr_p);
12479 --processing_template_decl;
12482 else if (TREE_CODE (arg) != OVERLOAD
12483 && TREE_CODE (arg) != FUNCTION_DECL)
12484 /* If ARG is, for example, "(0, &f)" then its type will be unknown
12485 -- but the deduction does not succeed because the expression is
12486 not just the function on its own. */
12489 for (; arg; arg = OVL_NEXT (arg))
12490 good += try_one_overload (tparms, targs, tempargs, parm,
12491 TREE_TYPE (OVL_CURRENT (arg)),
12492 strict, sub_strict, addr_p);
12494 /* [temp.deduct.type] A template-argument can be deduced from a pointer
12495 to function or pointer to member function argument if the set of
12496 overloaded functions does not contain function templates and at most
12497 one of a set of overloaded functions provides a unique match.
12499 So if we found multiple possibilities, we return success but don't
12500 deduce anything. */
12504 int i = TREE_VEC_LENGTH (targs);
12506 if (TREE_VEC_ELT (tempargs, i))
12507 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
12515 /* Subroutine of resolve_overloaded_unification; does deduction for a single
12516 overload. Fills TARGS with any deduced arguments, or error_mark_node if
12517 different overloads deduce different arguments for a given parm.
12518 ADDR_P is true if the expression for which deduction is being
12519 performed was of the form "& fn" rather than simply "fn".
12521 Returns 1 on success. */
12524 try_one_overload (tree tparms,
12529 unification_kind_t strict,
12537 /* [temp.deduct.type] A template-argument can be deduced from a pointer
12538 to function or pointer to member function argument if the set of
12539 overloaded functions does not contain function templates and at most
12540 one of a set of overloaded functions provides a unique match.
12542 So if this is a template, just return success. */
12544 if (uses_template_parms (arg))
12547 if (TREE_CODE (arg) == METHOD_TYPE)
12548 arg = build_ptrmemfunc_type (build_pointer_type (arg));
12550 arg = build_pointer_type (arg);
12552 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
12554 /* We don't copy orig_targs for this because if we have already deduced
12555 some template args from previous args, unify would complain when we
12556 try to deduce a template parameter for the same argument, even though
12557 there isn't really a conflict. */
12558 nargs = TREE_VEC_LENGTH (targs);
12559 tempargs = make_tree_vec (nargs);
12561 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
12564 /* First make sure we didn't deduce anything that conflicts with
12565 explicitly specified args. */
12566 for (i = nargs; i--; )
12568 tree elt = TREE_VEC_ELT (tempargs, i);
12569 tree oldelt = TREE_VEC_ELT (orig_targs, i);
12573 else if (uses_template_parms (elt))
12574 /* Since we're unifying against ourselves, we will fill in
12575 template args used in the function parm list with our own
12576 template parms. Discard them. */
12577 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
12578 else if (oldelt && !template_args_equal (oldelt, elt))
12582 for (i = nargs; i--; )
12584 tree elt = TREE_VEC_ELT (tempargs, i);
12587 TREE_VEC_ELT (targs, i) = elt;
12593 /* PARM is a template class (perhaps with unbound template
12594 parameters). ARG is a fully instantiated type. If ARG can be
12595 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
12596 TARGS are as for unify. */
12599 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
12601 tree copy_of_targs;
12603 if (!CLASSTYPE_TEMPLATE_INFO (arg)
12604 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
12605 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
12608 /* We need to make a new template argument vector for the call to
12609 unify. If we used TARGS, we'd clutter it up with the result of
12610 the attempted unification, even if this class didn't work out.
12611 We also don't want to commit ourselves to all the unifications
12612 we've already done, since unification is supposed to be done on
12613 an argument-by-argument basis. In other words, consider the
12614 following pathological case:
12616 template <int I, int J, int K>
12619 template <int I, int J>
12620 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
12622 template <int I, int J, int K>
12623 void f(S<I, J, K>, S<I, I, I>);
12632 Now, by the time we consider the unification involving `s2', we
12633 already know that we must have `f<0, 0, 0>'. But, even though
12634 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
12635 because there are two ways to unify base classes of S<0, 1, 2>
12636 with S<I, I, I>. If we kept the already deduced knowledge, we
12637 would reject the possibility I=1. */
12638 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
12640 /* If unification failed, we're done. */
12641 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
12642 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
12648 /* Given a template type PARM and a class type ARG, find the unique
12649 base type in ARG that is an instance of PARM. We do not examine
12650 ARG itself; only its base-classes. If there is not exactly one
12651 appropriate base class, return NULL_TREE. PARM may be the type of
12652 a partial specialization, as well as a plain template type. Used
12656 get_template_base (tree tparms, tree targs, tree parm, tree arg)
12658 tree rval = NULL_TREE;
12661 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
12663 binfo = TYPE_BINFO (complete_type (arg));
12665 /* The type could not be completed. */
12668 /* Walk in inheritance graph order. The search order is not
12669 important, and this avoids multiple walks of virtual bases. */
12670 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
12672 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
12676 /* If there is more than one satisfactory baseclass, then:
12680 If they yield more than one possible deduced A, the type
12684 if (rval && !same_type_p (r, rval))
12694 /* Returns the level of DECL, which declares a template parameter. */
12697 template_decl_level (tree decl)
12699 switch (TREE_CODE (decl))
12702 case TEMPLATE_DECL:
12703 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
12706 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
12709 gcc_unreachable ();
12714 /* Decide whether ARG can be unified with PARM, considering only the
12715 cv-qualifiers of each type, given STRICT as documented for unify.
12716 Returns nonzero iff the unification is OK on that basis. */
12719 check_cv_quals_for_unify (int strict, tree arg, tree parm)
12721 int arg_quals = cp_type_quals (arg);
12722 int parm_quals = cp_type_quals (parm);
12724 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
12725 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
12727 /* Although a CVR qualifier is ignored when being applied to a
12728 substituted template parameter ([8.3.2]/1 for example), that
12729 does not apply during deduction [14.8.2.4]/1, (even though
12730 that is not explicitly mentioned, [14.8.2.4]/9 indicates
12731 this). Except when we're allowing additional CV qualifiers
12732 at the outer level [14.8.2.1]/3,1st bullet. */
12733 if ((TREE_CODE (arg) == REFERENCE_TYPE
12734 || TREE_CODE (arg) == FUNCTION_TYPE
12735 || TREE_CODE (arg) == METHOD_TYPE)
12736 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
12739 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
12740 && (parm_quals & TYPE_QUAL_RESTRICT))
12744 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
12745 && (arg_quals & parm_quals) != parm_quals)
12748 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
12749 && (parm_quals & arg_quals) != arg_quals)
12755 /* Determines the LEVEL and INDEX for the template parameter PARM. */
12757 template_parm_level_and_index (tree parm, int* level, int* index)
12759 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
12760 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
12761 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
12763 *index = TEMPLATE_TYPE_IDX (parm);
12764 *level = TEMPLATE_TYPE_LEVEL (parm);
12768 *index = TEMPLATE_PARM_IDX (parm);
12769 *level = TEMPLATE_PARM_LEVEL (parm);
12773 /* Unifies the remaining arguments in PACKED_ARGS with the pack
12774 expansion at the end of PACKED_PARMS. Returns 0 if the type
12775 deduction succeeds, 1 otherwise. STRICT is the same as in
12776 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
12777 call argument list. We'll need to adjust the arguments to make them
12778 types. SUBR tells us if this is from a recursive call to
12779 type_unification_real. */
12781 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
12782 tree packed_args, int strict, bool call_args_p,
12786 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
12787 tree pattern = PACK_EXPANSION_PATTERN (parm);
12788 tree pack, packs = NULL_TREE;
12789 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
12790 int len = TREE_VEC_LENGTH (packed_args);
12792 /* Determine the parameter packs we will be deducing from the
12793 pattern, and record their current deductions. */
12794 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
12795 pack; pack = TREE_CHAIN (pack))
12797 tree parm_pack = TREE_VALUE (pack);
12800 /* Determine the index and level of this parameter pack. */
12801 template_parm_level_and_index (parm_pack, &level, &idx);
12803 /* Keep track of the parameter packs and their corresponding
12805 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
12806 TREE_TYPE (packs) = make_tree_vec (len - start);
12809 /* Loop through all of the arguments that have not yet been
12810 unified and unify each with the pattern. */
12811 for (i = start; i < len; i++)
12813 tree parm = pattern;
12815 /* For each parameter pack, clear out the deduced value so that
12816 we can deduce it again. */
12817 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12820 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12822 TMPL_ARG (targs, level, idx) = NULL_TREE;
12825 /* Unify the pattern with the current argument. */
12827 tree arg = TREE_VEC_ELT (packed_args, i);
12828 tree arg_expr = NULL_TREE;
12829 int arg_strict = strict;
12830 bool skip_arg_p = false;
12836 /* This mirrors what we do in type_unification_real. */
12840 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
12841 | UNIFY_ALLOW_MORE_CV_QUAL
12842 | UNIFY_ALLOW_DERIVED);
12846 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
12850 sub_strict = UNIFY_ALLOW_NONE;
12854 gcc_unreachable ();
12859 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
12860 if (type_unknown_p (arg))
12862 /* [temp.deduct.type] A template-argument can be
12863 deduced from a pointer to function or pointer
12864 to member function argument if the set of
12865 overloaded functions does not contain function
12866 templates and at most one of a set of
12867 overloaded functions provides a unique
12870 if (resolve_overloaded_unification
12871 (tparms, targs, parm, arg, strict, sub_strict)
12880 arg = unlowered_expr_type (arg);
12881 if (arg == error_mark_node)
12886 arg_strict = sub_strict;
12890 maybe_adjust_types_for_deduction (strict, &parm, &arg,
12896 if (unify (tparms, targs, parm, arg, arg_strict))
12901 /* For each parameter pack, collect the deduced value. */
12902 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12905 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12907 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
12908 TMPL_ARG (targs, level, idx);
12912 /* Verify that the results of unification with the parameter packs
12913 produce results consistent with what we've seen before, and make
12914 the deduced argument packs available. */
12915 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12917 tree old_pack = TREE_VALUE (pack);
12918 tree new_args = TREE_TYPE (pack);
12919 int i, len = TREE_VEC_LENGTH (new_args);
12920 bool nondeduced_p = false;
12922 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
12923 actually deduce anything. */
12924 for (i = 0; i < len && !nondeduced_p; ++i)
12925 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
12926 nondeduced_p = true;
12930 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
12932 /* Prepend the explicit arguments onto NEW_ARGS. */
12933 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
12934 tree old_args = new_args;
12935 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
12936 int len = explicit_len + TREE_VEC_LENGTH (old_args);
12938 /* Copy the explicit arguments. */
12939 new_args = make_tree_vec (len);
12940 for (i = 0; i < explicit_len; i++)
12941 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
12943 /* Copy the deduced arguments. */
12944 for (; i < len; i++)
12945 TREE_VEC_ELT (new_args, i) =
12946 TREE_VEC_ELT (old_args, i - explicit_len);
12954 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12956 /* Build the deduced *_ARGUMENT_PACK. */
12957 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
12959 result = make_node (NONTYPE_ARGUMENT_PACK);
12960 TREE_TYPE (result) =
12961 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
12962 TREE_CONSTANT (result) = 1;
12965 result = make_node (TYPE_ARGUMENT_PACK);
12967 SET_ARGUMENT_PACK_ARGS (result, new_args);
12969 /* Note the deduced argument packs for this parameter
12971 TMPL_ARG (targs, level, idx) = result;
12973 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
12974 && (ARGUMENT_PACK_ARGS (old_pack)
12975 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
12977 /* We only had the explicitly-provided arguments before, but
12978 now we have a complete set of arguments. */
12980 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
12981 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12983 /* Keep the original deduced argument pack. */
12984 TMPL_ARG (targs, level, idx) = old_pack;
12986 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
12987 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
12988 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
12990 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
12992 /* Inconsistent unification of this parameter pack. */
12998 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13000 /* Keep the original deduced argument pack. */
13001 TMPL_ARG (targs, level, idx) = old_pack;
13008 /* Deduce the value of template parameters. TPARMS is the (innermost)
13009 set of template parameters to a template. TARGS is the bindings
13010 for those template parameters, as determined thus far; TARGS may
13011 include template arguments for outer levels of template parameters
13012 as well. PARM is a parameter to a template function, or a
13013 subcomponent of that parameter; ARG is the corresponding argument.
13014 This function attempts to match PARM with ARG in a manner
13015 consistent with the existing assignments in TARGS. If more values
13016 are deduced, then TARGS is updated.
13018 Returns 0 if the type deduction succeeds, 1 otherwise. The
13019 parameter STRICT is a bitwise or of the following flags:
13022 Require an exact match between PARM and ARG.
13023 UNIFY_ALLOW_MORE_CV_QUAL:
13024 Allow the deduced ARG to be more cv-qualified (by qualification
13025 conversion) than ARG.
13026 UNIFY_ALLOW_LESS_CV_QUAL:
13027 Allow the deduced ARG to be less cv-qualified than ARG.
13028 UNIFY_ALLOW_DERIVED:
13029 Allow the deduced ARG to be a template base class of ARG,
13030 or a pointer to a template base class of the type pointed to by
13032 UNIFY_ALLOW_INTEGER:
13033 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
13034 case for more information.
13035 UNIFY_ALLOW_OUTER_LEVEL:
13036 This is the outermost level of a deduction. Used to determine validity
13037 of qualification conversions. A valid qualification conversion must
13038 have const qualified pointers leading up to the inner type which
13039 requires additional CV quals, except at the outer level, where const
13040 is not required [conv.qual]. It would be normal to set this flag in
13041 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
13042 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
13043 This is the outermost level of a deduction, and PARM can be more CV
13044 qualified at this point.
13045 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
13046 This is the outermost level of a deduction, and PARM can be less CV
13047 qualified at this point. */
13050 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
13055 int strict_in = strict;
13057 /* I don't think this will do the right thing with respect to types.
13058 But the only case I've seen it in so far has been array bounds, where
13059 signedness is the only information lost, and I think that will be
13061 while (TREE_CODE (parm) == NOP_EXPR)
13062 parm = TREE_OPERAND (parm, 0);
13064 if (arg == error_mark_node)
13066 if (arg == unknown_type_node
13067 || arg == init_list_type_node)
13068 /* We can't deduce anything from this, but we might get all the
13069 template args from other function args. */
13072 /* If PARM uses template parameters, then we can't bail out here,
13073 even if ARG == PARM, since we won't record unifications for the
13074 template parameters. We might need them if we're trying to
13075 figure out which of two things is more specialized. */
13076 if (arg == parm && !uses_template_parms (parm))
13079 /* Handle init lists early, so the rest of the function can assume
13080 we're dealing with a type. */
13081 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
13086 if (!is_std_init_list (parm))
13087 /* We can only deduce from an initializer list argument if the
13088 parameter is std::initializer_list; otherwise this is a
13089 non-deduced context. */
13092 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
13094 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
13096 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
13097 elt = TREE_TYPE (elt);
13098 if (unify (tparms, targs, elttype, elt, UNIFY_ALLOW_NONE))
13104 /* Immediately reject some pairs that won't unify because of
13105 cv-qualification mismatches. */
13106 if (TREE_CODE (arg) == TREE_CODE (parm)
13108 /* It is the elements of the array which hold the cv quals of an array
13109 type, and the elements might be template type parms. We'll check
13110 when we recurse. */
13111 && TREE_CODE (arg) != ARRAY_TYPE
13112 /* We check the cv-qualifiers when unifying with template type
13113 parameters below. We want to allow ARG `const T' to unify with
13114 PARM `T' for example, when computing which of two templates
13115 is more specialized, for example. */
13116 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
13117 && !check_cv_quals_for_unify (strict_in, arg, parm))
13120 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
13121 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
13122 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
13123 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
13124 strict &= ~UNIFY_ALLOW_DERIVED;
13125 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
13126 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
13128 switch (TREE_CODE (parm))
13130 case TYPENAME_TYPE:
13132 case UNBOUND_CLASS_TEMPLATE:
13133 /* In a type which contains a nested-name-specifier, template
13134 argument values cannot be deduced for template parameters used
13135 within the nested-name-specifier. */
13138 case TEMPLATE_TYPE_PARM:
13139 case TEMPLATE_TEMPLATE_PARM:
13140 case BOUND_TEMPLATE_TEMPLATE_PARM:
13141 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
13142 if (tparm == error_mark_node)
13145 if (TEMPLATE_TYPE_LEVEL (parm)
13146 != template_decl_level (tparm))
13147 /* The PARM is not one we're trying to unify. Just check
13148 to see if it matches ARG. */
13149 return (TREE_CODE (arg) == TREE_CODE (parm)
13150 && same_type_p (parm, arg)) ? 0 : 1;
13151 idx = TEMPLATE_TYPE_IDX (parm);
13152 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
13153 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
13155 /* Check for mixed types and values. */
13156 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13157 && TREE_CODE (tparm) != TYPE_DECL)
13158 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13159 && TREE_CODE (tparm) != TEMPLATE_DECL))
13162 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13164 /* ARG must be constructed from a template class or a template
13165 template parameter. */
13166 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
13167 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
13171 tree parmvec = TYPE_TI_ARGS (parm);
13172 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
13174 = DECL_INNERMOST_TEMPLATE_PARMS
13175 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
13177 int parm_variadic_p = 0;
13179 /* The resolution to DR150 makes clear that default
13180 arguments for an N-argument may not be used to bind T
13181 to a template template parameter with fewer than N
13182 parameters. It is not safe to permit the binding of
13183 default arguments as an extension, as that may change
13184 the meaning of a conforming program. Consider:
13186 struct Dense { static const unsigned int dim = 1; };
13188 template <template <typename> class View,
13190 void operator+(float, View<Block> const&);
13192 template <typename Block,
13193 unsigned int Dim = Block::dim>
13194 struct Lvalue_proxy { operator float() const; };
13198 Lvalue_proxy<Dense> p;
13203 Here, if Lvalue_proxy is permitted to bind to View, then
13204 the global operator+ will be used; if they are not, the
13205 Lvalue_proxy will be converted to float. */
13206 if (coerce_template_parms (parm_parms,
13208 TYPE_TI_TEMPLATE (parm),
13210 /*require_all_args=*/true,
13211 /*use_default_args=*/false)
13212 == error_mark_node)
13215 /* Deduce arguments T, i from TT<T> or TT<i>.
13216 We check each element of PARMVEC and ARGVEC individually
13217 rather than the whole TREE_VEC since they can have
13218 different number of elements. */
13220 parmvec = expand_template_argument_pack (parmvec);
13221 argvec = expand_template_argument_pack (argvec);
13223 len = TREE_VEC_LENGTH (parmvec);
13225 /* Check if the parameters end in a pack, making them
13228 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
13229 parm_variadic_p = 1;
13231 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
13234 for (i = 0; i < len - parm_variadic_p; ++i)
13236 if (unify (tparms, targs,
13237 TREE_VEC_ELT (parmvec, i),
13238 TREE_VEC_ELT (argvec, i),
13243 if (parm_variadic_p
13244 && unify_pack_expansion (tparms, targs,
13247 /*call_args_p=*/false,
13251 arg = TYPE_TI_TEMPLATE (arg);
13253 /* Fall through to deduce template name. */
13256 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13257 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13259 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
13261 /* Simple cases: Value already set, does match or doesn't. */
13262 if (targ != NULL_TREE && template_args_equal (targ, arg))
13269 /* If PARM is `const T' and ARG is only `int', we don't have
13270 a match unless we are allowing additional qualification.
13271 If ARG is `const int' and PARM is just `T' that's OK;
13272 that binds `const int' to `T'. */
13273 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
13277 /* Consider the case where ARG is `const volatile int' and
13278 PARM is `const T'. Then, T should be `volatile int'. */
13279 arg = cp_build_qualified_type_real
13280 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
13281 if (arg == error_mark_node)
13284 /* Simple cases: Value already set, does match or doesn't. */
13285 if (targ != NULL_TREE && same_type_p (targ, arg))
13290 /* Make sure that ARG is not a variable-sized array. (Note
13291 that were talking about variable-sized arrays (like
13292 `int[n]'), rather than arrays of unknown size (like
13293 `int[]').) We'll get very confused by such a type since
13294 the bound of the array will not be computable in an
13295 instantiation. Besides, such types are not allowed in
13296 ISO C++, so we can do as we please here. */
13297 if (variably_modified_type_p (arg, NULL_TREE))
13301 /* If ARG is a parameter pack or an expansion, we cannot unify
13302 against it unless PARM is also a parameter pack. */
13303 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
13304 && !template_parameter_pack_p (parm))
13307 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
13310 case TEMPLATE_PARM_INDEX:
13311 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
13312 if (tparm == error_mark_node)
13315 if (TEMPLATE_PARM_LEVEL (parm)
13316 != template_decl_level (tparm))
13317 /* The PARM is not one we're trying to unify. Just check
13318 to see if it matches ARG. */
13319 return !(TREE_CODE (arg) == TREE_CODE (parm)
13320 && cp_tree_equal (parm, arg));
13322 idx = TEMPLATE_PARM_IDX (parm);
13323 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
13326 return !cp_tree_equal (targ, arg);
13328 /* [temp.deduct.type] If, in the declaration of a function template
13329 with a non-type template-parameter, the non-type
13330 template-parameter is used in an expression in the function
13331 parameter-list and, if the corresponding template-argument is
13332 deduced, the template-argument type shall match the type of the
13333 template-parameter exactly, except that a template-argument
13334 deduced from an array bound may be of any integral type.
13335 The non-type parameter might use already deduced type parameters. */
13336 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
13337 if (!TREE_TYPE (arg))
13338 /* Template-parameter dependent expression. Just accept it for now.
13339 It will later be processed in convert_template_argument. */
13341 else if (same_type_p (TREE_TYPE (arg), tparm))
13343 else if ((strict & UNIFY_ALLOW_INTEGER)
13344 && (TREE_CODE (tparm) == INTEGER_TYPE
13345 || TREE_CODE (tparm) == BOOLEAN_TYPE))
13346 /* Convert the ARG to the type of PARM; the deduced non-type
13347 template argument must exactly match the types of the
13348 corresponding parameter. */
13349 arg = fold (build_nop (TREE_TYPE (parm), arg));
13350 else if (uses_template_parms (tparm))
13351 /* We haven't deduced the type of this parameter yet. Try again
13357 /* If ARG is a parameter pack or an expansion, we cannot unify
13358 against it unless PARM is also a parameter pack. */
13359 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
13360 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
13363 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
13368 /* A pointer-to-member constant can be unified only with
13369 another constant. */
13370 if (TREE_CODE (arg) != PTRMEM_CST)
13373 /* Just unify the class member. It would be useless (and possibly
13374 wrong, depending on the strict flags) to unify also
13375 PTRMEM_CST_CLASS, because we want to be sure that both parm and
13376 arg refer to the same variable, even if through different
13377 classes. For instance:
13379 struct A { int x; };
13382 Unification of &A::x and &B::x must succeed. */
13383 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
13384 PTRMEM_CST_MEMBER (arg), strict);
13389 if (TREE_CODE (arg) != POINTER_TYPE)
13392 /* [temp.deduct.call]
13394 A can be another pointer or pointer to member type that can
13395 be converted to the deduced A via a qualification
13396 conversion (_conv.qual_).
13398 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
13399 This will allow for additional cv-qualification of the
13400 pointed-to types if appropriate. */
13402 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
13403 /* The derived-to-base conversion only persists through one
13404 level of pointers. */
13405 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
13407 return unify (tparms, targs, TREE_TYPE (parm),
13408 TREE_TYPE (arg), strict);
13411 case REFERENCE_TYPE:
13412 if (TREE_CODE (arg) != REFERENCE_TYPE)
13414 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
13415 strict & UNIFY_ALLOW_MORE_CV_QUAL);
13418 if (TREE_CODE (arg) != ARRAY_TYPE)
13420 if ((TYPE_DOMAIN (parm) == NULL_TREE)
13421 != (TYPE_DOMAIN (arg) == NULL_TREE))
13423 if (TYPE_DOMAIN (parm) != NULL_TREE)
13430 /* Our representation of array types uses "N - 1" as the
13431 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
13432 not an integer constant. We cannot unify arbitrarily
13433 complex expressions, so we eliminate the MINUS_EXPRs
13435 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
13436 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
13439 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
13440 parm_max = TREE_OPERAND (parm_max, 0);
13442 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
13443 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
13446 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
13447 trying to unify the type of a variable with the type
13448 of a template parameter. For example:
13450 template <unsigned int N>
13451 void f (char (&) [N]);
13458 Here, the type of the ARG will be "int [g(i)]", and
13459 may be a SAVE_EXPR, etc. */
13460 if (TREE_CODE (arg_max) != MINUS_EXPR)
13462 arg_max = TREE_OPERAND (arg_max, 0);
13465 /* If only one of the bounds used a MINUS_EXPR, compensate
13466 by adding one to the other bound. */
13467 if (parm_cst && !arg_cst)
13468 parm_max = fold_build2 (PLUS_EXPR,
13472 else if (arg_cst && !parm_cst)
13473 arg_max = fold_build2 (PLUS_EXPR,
13478 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
13481 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
13482 strict & UNIFY_ALLOW_MORE_CV_QUAL);
13489 case ENUMERAL_TYPE:
13491 if (TREE_CODE (arg) != TREE_CODE (parm))
13494 /* We have already checked cv-qualification at the top of the
13496 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
13499 /* As far as unification is concerned, this wins. Later checks
13500 will invalidate it if necessary. */
13503 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
13504 /* Type INTEGER_CST can come from ordinary constant template args. */
13506 while (TREE_CODE (arg) == NOP_EXPR)
13507 arg = TREE_OPERAND (arg, 0);
13509 if (TREE_CODE (arg) != INTEGER_CST)
13511 return !tree_int_cst_equal (parm, arg);
13516 if (TREE_CODE (arg) != TREE_VEC)
13518 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
13520 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
13521 if (unify (tparms, targs,
13522 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
13530 if (TREE_CODE (arg) != TREE_CODE (parm))
13533 if (TYPE_PTRMEMFUNC_P (parm))
13535 if (!TYPE_PTRMEMFUNC_P (arg))
13538 return unify (tparms, targs,
13539 TYPE_PTRMEMFUNC_FN_TYPE (parm),
13540 TYPE_PTRMEMFUNC_FN_TYPE (arg),
13544 if (CLASSTYPE_TEMPLATE_INFO (parm))
13546 tree t = NULL_TREE;
13548 if (strict_in & UNIFY_ALLOW_DERIVED)
13550 /* First, we try to unify the PARM and ARG directly. */
13551 t = try_class_unification (tparms, targs,
13556 /* Fallback to the special case allowed in
13557 [temp.deduct.call]:
13559 If P is a class, and P has the form
13560 template-id, then A can be a derived class of
13561 the deduced A. Likewise, if P is a pointer to
13562 a class of the form template-id, A can be a
13563 pointer to a derived class pointed to by the
13565 t = get_template_base (tparms, targs, parm, arg);
13571 else if (CLASSTYPE_TEMPLATE_INFO (arg)
13572 && (CLASSTYPE_TI_TEMPLATE (parm)
13573 == CLASSTYPE_TI_TEMPLATE (arg)))
13574 /* Perhaps PARM is something like S<U> and ARG is S<int>.
13575 Then, we should unify `int' and `U'. */
13578 /* There's no chance of unification succeeding. */
13581 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
13582 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
13584 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
13589 case FUNCTION_TYPE:
13590 if (TREE_CODE (arg) != TREE_CODE (parm))
13593 /* CV qualifications for methods can never be deduced, they must
13594 match exactly. We need to check them explicitly here,
13595 because type_unification_real treats them as any other
13596 cv-qualified parameter. */
13597 if (TREE_CODE (parm) == METHOD_TYPE
13598 && (!check_cv_quals_for_unify
13600 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
13601 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
13604 if (unify (tparms, targs, TREE_TYPE (parm),
13605 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
13607 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
13608 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
13612 /* Unify a pointer to member with a pointer to member function, which
13613 deduces the type of the member as a function type. */
13614 if (TYPE_PTRMEMFUNC_P (arg))
13618 cp_cv_quals cv_quals;
13620 /* Check top-level cv qualifiers */
13621 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
13624 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
13625 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
13628 /* Determine the type of the function we are unifying against. */
13629 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
13631 build_function_type (TREE_TYPE (method_type),
13632 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
13634 /* Extract the cv-qualifiers of the member function from the
13635 implicit object parameter and place them on the function
13636 type to be restored later. */
13638 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
13639 fntype = build_qualified_type (fntype, cv_quals);
13640 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
13643 if (TREE_CODE (arg) != OFFSET_TYPE)
13645 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
13646 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
13648 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
13652 if (DECL_TEMPLATE_PARM_P (parm))
13653 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
13654 if (arg != integral_constant_value (parm))
13659 case TEMPLATE_DECL:
13660 /* Matched cases are handled by the ARG == PARM test above. */
13663 case TYPE_ARGUMENT_PACK:
13664 case NONTYPE_ARGUMENT_PACK:
13666 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
13667 tree packed_args = ARGUMENT_PACK_ARGS (arg);
13668 int i, len = TREE_VEC_LENGTH (packed_parms);
13669 int argslen = TREE_VEC_LENGTH (packed_args);
13670 int parm_variadic_p = 0;
13672 for (i = 0; i < len; ++i)
13674 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
13677 /* We can unify against something with a trailing
13679 parm_variadic_p = 1;
13681 /* Since there is something following the pack
13682 expansion, we cannot unify this template argument
13689 /* If we don't have enough arguments to satisfy the parameters
13690 (not counting the pack expression at the end), or we have
13691 too many arguments for a parameter list that doesn't end in
13692 a pack expression, we can't unify. */
13693 if (argslen < (len - parm_variadic_p)
13694 || (argslen > len && !parm_variadic_p))
13697 /* Unify all of the parameters that precede the (optional)
13698 pack expression. */
13699 for (i = 0; i < len - parm_variadic_p; ++i)
13701 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
13702 TREE_VEC_ELT (packed_args, i), strict))
13706 if (parm_variadic_p)
13707 return unify_pack_expansion (tparms, targs,
13708 packed_parms, packed_args,
13709 strict, /*call_args_p=*/false,
13717 case DECLTYPE_TYPE:
13718 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
13723 /* Unification fails if we hit an error node. */
13727 gcc_assert (EXPR_P (parm));
13729 /* We must be looking at an expression. This can happen with
13733 void foo(S<I>, S<I + 2>);
13735 This is a "nondeduced context":
13739 The nondeduced contexts are:
13741 --A type that is a template-id in which one or more of
13742 the template-arguments is an expression that references
13743 a template-parameter.
13745 In these cases, we assume deduction succeeded, but don't
13746 actually infer any unifications. */
13748 if (!uses_template_parms (parm)
13749 && !template_args_equal (parm, arg))
13756 /* Note that DECL can be defined in this translation unit, if
13760 mark_definable (tree decl)
13763 DECL_NOT_REALLY_EXTERN (decl) = 1;
13764 FOR_EACH_CLONE (clone, decl)
13765 DECL_NOT_REALLY_EXTERN (clone) = 1;
13768 /* Called if RESULT is explicitly instantiated, or is a member of an
13769 explicitly instantiated class. */
13772 mark_decl_instantiated (tree result, int extern_p)
13774 SET_DECL_EXPLICIT_INSTANTIATION (result);
13776 /* If this entity has already been written out, it's too late to
13777 make any modifications. */
13778 if (TREE_ASM_WRITTEN (result))
13781 if (TREE_CODE (result) != FUNCTION_DECL)
13782 /* The TREE_PUBLIC flag for function declarations will have been
13783 set correctly by tsubst. */
13784 TREE_PUBLIC (result) = 1;
13786 /* This might have been set by an earlier implicit instantiation. */
13787 DECL_COMDAT (result) = 0;
13790 DECL_NOT_REALLY_EXTERN (result) = 0;
13793 mark_definable (result);
13794 /* Always make artificials weak. */
13795 if (DECL_ARTIFICIAL (result) && flag_weak)
13796 comdat_linkage (result);
13797 /* For WIN32 we also want to put explicit instantiations in
13798 linkonce sections. */
13799 else if (TREE_PUBLIC (result))
13800 maybe_make_one_only (result);
13803 /* If EXTERN_P, then this function will not be emitted -- unless
13804 followed by an explicit instantiation, at which point its linkage
13805 will be adjusted. If !EXTERN_P, then this function will be
13806 emitted here. In neither circumstance do we want
13807 import_export_decl to adjust the linkage. */
13808 DECL_INTERFACE_KNOWN (result) = 1;
13811 /* Given two function templates PAT1 and PAT2, return:
13813 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
13814 -1 if PAT2 is more specialized than PAT1.
13815 0 if neither is more specialized.
13817 LEN indicates the number of parameters we should consider
13818 (defaulted parameters should not be considered).
13820 The 1998 std underspecified function template partial ordering, and
13821 DR214 addresses the issue. We take pairs of arguments, one from
13822 each of the templates, and deduce them against each other. One of
13823 the templates will be more specialized if all the *other*
13824 template's arguments deduce against its arguments and at least one
13825 of its arguments *does* *not* deduce against the other template's
13826 corresponding argument. Deduction is done as for class templates.
13827 The arguments used in deduction have reference and top level cv
13828 qualifiers removed. Iff both arguments were originally reference
13829 types *and* deduction succeeds in both directions, the template
13830 with the more cv-qualified argument wins for that pairing (if
13831 neither is more cv-qualified, they both are equal). Unlike regular
13832 deduction, after all the arguments have been deduced in this way,
13833 we do *not* verify the deduced template argument values can be
13834 substituted into non-deduced contexts, nor do we have to verify
13835 that all template arguments have been deduced. */
13838 more_specialized_fn (tree pat1, tree pat2, int len)
13840 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
13841 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
13842 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
13843 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
13844 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
13845 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
13846 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
13847 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
13851 /* Remove the this parameter from non-static member functions. If
13852 one is a non-static member function and the other is not a static
13853 member function, remove the first parameter from that function
13854 also. This situation occurs for operator functions where we
13855 locate both a member function (with this pointer) and non-member
13856 operator (with explicit first operand). */
13857 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
13859 len--; /* LEN is the number of significant arguments for DECL1 */
13860 args1 = TREE_CHAIN (args1);
13861 if (!DECL_STATIC_FUNCTION_P (decl2))
13862 args2 = TREE_CHAIN (args2);
13864 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
13866 args2 = TREE_CHAIN (args2);
13867 if (!DECL_STATIC_FUNCTION_P (decl1))
13870 args1 = TREE_CHAIN (args1);
13874 /* If only one is a conversion operator, they are unordered. */
13875 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
13878 /* Consider the return type for a conversion function */
13879 if (DECL_CONV_FN_P (decl1))
13881 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
13882 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
13886 processing_template_decl++;
13889 /* Stop when an ellipsis is seen. */
13890 && args1 != NULL_TREE && args2 != NULL_TREE)
13892 tree arg1 = TREE_VALUE (args1);
13893 tree arg2 = TREE_VALUE (args2);
13894 int deduce1, deduce2;
13898 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
13899 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
13901 /* When both arguments are pack expansions, we need only
13902 unify the patterns themselves. */
13903 arg1 = PACK_EXPANSION_PATTERN (arg1);
13904 arg2 = PACK_EXPANSION_PATTERN (arg2);
13906 /* This is the last comparison we need to do. */
13910 if (TREE_CODE (arg1) == REFERENCE_TYPE)
13912 arg1 = TREE_TYPE (arg1);
13913 quals1 = cp_type_quals (arg1);
13916 if (TREE_CODE (arg2) == REFERENCE_TYPE)
13918 arg2 = TREE_TYPE (arg2);
13919 quals2 = cp_type_quals (arg2);
13922 if ((quals1 < 0) != (quals2 < 0))
13924 /* Only of the args is a reference, see if we should apply
13925 array/function pointer decay to it. This is not part of
13926 DR214, but is, IMHO, consistent with the deduction rules
13927 for the function call itself, and with our earlier
13928 implementation of the underspecified partial ordering
13929 rules. (nathan). */
13932 switch (TREE_CODE (arg1))
13935 arg1 = TREE_TYPE (arg1);
13937 case FUNCTION_TYPE:
13938 arg1 = build_pointer_type (arg1);
13947 switch (TREE_CODE (arg2))
13950 arg2 = TREE_TYPE (arg2);
13952 case FUNCTION_TYPE:
13953 arg2 = build_pointer_type (arg2);
13962 arg1 = TYPE_MAIN_VARIANT (arg1);
13963 arg2 = TYPE_MAIN_VARIANT (arg2);
13965 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
13967 int i, len2 = list_length (args2);
13968 tree parmvec = make_tree_vec (1);
13969 tree argvec = make_tree_vec (len2);
13972 /* Setup the parameter vector, which contains only ARG1. */
13973 TREE_VEC_ELT (parmvec, 0) = arg1;
13975 /* Setup the argument vector, which contains the remaining
13977 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
13978 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
13980 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
13981 argvec, UNIFY_ALLOW_NONE,
13982 /*call_args_p=*/false,
13985 /* We cannot deduce in the other direction, because ARG1 is
13986 a pack expansion but ARG2 is not. */
13989 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
13991 int i, len1 = list_length (args1);
13992 tree parmvec = make_tree_vec (1);
13993 tree argvec = make_tree_vec (len1);
13996 /* Setup the parameter vector, which contains only ARG1. */
13997 TREE_VEC_ELT (parmvec, 0) = arg2;
13999 /* Setup the argument vector, which contains the remaining
14001 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
14002 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
14004 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
14005 argvec, UNIFY_ALLOW_NONE,
14006 /*call_args_p=*/false,
14009 /* We cannot deduce in the other direction, because ARG2 is
14010 a pack expansion but ARG1 is not.*/
14016 /* The normal case, where neither argument is a pack
14018 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
14019 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
14026 if (better1 < 0 && better2 < 0)
14027 /* We've failed to deduce something in either direction.
14028 These must be unordered. */
14031 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
14033 /* Deduces in both directions, see if quals can
14034 disambiguate. Pretend the worse one failed to deduce. */
14035 if ((quals1 & quals2) == quals2)
14037 if ((quals1 & quals2) == quals1)
14040 if (deduce1 && !deduce2 && !better2)
14042 if (deduce2 && !deduce1 && !better1)
14045 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
14046 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
14047 /* We have already processed all of the arguments in our
14048 handing of the pack expansion type. */
14051 args1 = TREE_CHAIN (args1);
14052 args2 = TREE_CHAIN (args2);
14055 processing_template_decl--;
14057 /* All things being equal, if the next argument is a pack expansion
14058 for one function but not for the other, prefer the
14059 non-variadic function. */
14060 if ((better1 > 0) - (better2 > 0) == 0
14061 && args1 && TREE_VALUE (args1)
14062 && args2 && TREE_VALUE (args2))
14064 if (TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION)
14065 return TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION ? 0 : -1;
14066 else if (TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION)
14070 return (better1 > 0) - (better2 > 0);
14073 /* Determine which of two partial specializations is more specialized.
14075 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
14076 to the first partial specialization. The TREE_VALUE is the
14077 innermost set of template parameters for the partial
14078 specialization. PAT2 is similar, but for the second template.
14080 Return 1 if the first partial specialization is more specialized;
14081 -1 if the second is more specialized; 0 if neither is more
14084 See [temp.class.order] for information about determining which of
14085 two templates is more specialized. */
14088 more_specialized_class (tree pat1, tree pat2)
14093 bool any_deductions = false;
14095 tmpl1 = TREE_TYPE (pat1);
14096 tmpl2 = TREE_TYPE (pat2);
14098 /* Just like what happens for functions, if we are ordering between
14099 different class template specializations, we may encounter dependent
14100 types in the arguments, and we need our dependency check functions
14101 to behave correctly. */
14102 ++processing_template_decl;
14103 targs = get_class_bindings (TREE_VALUE (pat1),
14104 CLASSTYPE_TI_ARGS (tmpl1),
14105 CLASSTYPE_TI_ARGS (tmpl2));
14109 any_deductions = true;
14112 targs = get_class_bindings (TREE_VALUE (pat2),
14113 CLASSTYPE_TI_ARGS (tmpl2),
14114 CLASSTYPE_TI_ARGS (tmpl1));
14118 any_deductions = true;
14120 --processing_template_decl;
14122 /* In the case of a tie where at least one of the class templates
14123 has a parameter pack at the end, the template with the most
14124 non-packed parameters wins. */
14127 && (template_args_variadic_p (TREE_PURPOSE (pat1))
14128 || template_args_variadic_p (TREE_PURPOSE (pat2))))
14130 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
14131 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
14132 int len1 = TREE_VEC_LENGTH (args1);
14133 int len2 = TREE_VEC_LENGTH (args2);
14135 /* We don't count the pack expansion at the end. */
14136 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
14138 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
14143 else if (len1 < len2)
14150 /* Return the template arguments that will produce the function signature
14151 DECL from the function template FN, with the explicit template
14152 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
14153 also match. Return NULL_TREE if no satisfactory arguments could be
14157 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
14159 int ntparms = DECL_NTPARMS (fn);
14160 tree targs = make_tree_vec (ntparms);
14162 tree decl_arg_types;
14164 /* Substitute the explicit template arguments into the type of DECL.
14165 The call to fn_type_unification will handle substitution into the
14167 decl_type = TREE_TYPE (decl);
14168 if (explicit_args && uses_template_parms (decl_type))
14171 tree converted_args;
14173 if (DECL_TEMPLATE_INFO (decl))
14174 tmpl = DECL_TI_TEMPLATE (decl);
14176 /* We can get here for some invalid specializations. */
14180 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
14181 explicit_args, NULL_TREE,
14183 /*require_all_args=*/false,
14184 /*use_default_args=*/false);
14185 if (converted_args == error_mark_node)
14188 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
14189 if (decl_type == error_mark_node)
14193 /* Never do unification on the 'this' parameter. */
14194 decl_arg_types = skip_artificial_parms_for (decl,
14195 TYPE_ARG_TYPES (decl_type));
14197 if (fn_type_unification (fn, explicit_args, targs,
14199 (check_rettype || DECL_CONV_FN_P (fn)
14200 ? TREE_TYPE (decl_type) : NULL_TREE),
14201 DEDUCE_EXACT, LOOKUP_NORMAL))
14207 /* Return the innermost template arguments that, when applied to a
14208 template specialization whose innermost template parameters are
14209 TPARMS, and whose specialization arguments are PARMS, yield the
14212 For example, suppose we have:
14214 template <class T, class U> struct S {};
14215 template <class T> struct S<T*, int> {};
14217 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
14218 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
14219 int}. The resulting vector will be {double}, indicating that `T'
14220 is bound to `double'. */
14223 get_class_bindings (tree tparms, tree spec_args, tree args)
14225 int i, ntparms = TREE_VEC_LENGTH (tparms);
14227 tree innermost_deduced_args;
14229 innermost_deduced_args = make_tree_vec (ntparms);
14230 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
14232 deduced_args = copy_node (args);
14233 SET_TMPL_ARGS_LEVEL (deduced_args,
14234 TMPL_ARGS_DEPTH (deduced_args),
14235 innermost_deduced_args);
14238 deduced_args = innermost_deduced_args;
14240 if (unify (tparms, deduced_args,
14241 INNERMOST_TEMPLATE_ARGS (spec_args),
14242 INNERMOST_TEMPLATE_ARGS (args),
14246 for (i = 0; i < ntparms; ++i)
14247 if (! TREE_VEC_ELT (innermost_deduced_args, i))
14250 /* Verify that nondeduced template arguments agree with the type
14251 obtained from argument deduction.
14255 struct A { typedef int X; };
14256 template <class T, class U> struct C {};
14257 template <class T> struct C<T, typename T::X> {};
14259 Then with the instantiation `C<A, int>', we can deduce that
14260 `T' is `A' but unify () does not check whether `typename T::X'
14262 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
14263 if (spec_args == error_mark_node
14264 /* We only need to check the innermost arguments; the other
14265 arguments will always agree. */
14266 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
14267 INNERMOST_TEMPLATE_ARGS (args)))
14270 /* Now that we have bindings for all of the template arguments,
14271 ensure that the arguments deduced for the template template
14272 parameters have compatible template parameter lists. See the use
14273 of template_template_parm_bindings_ok_p in fn_type_unification
14274 for more information. */
14275 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
14278 return deduced_args;
14281 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
14282 Return the TREE_LIST node with the most specialized template, if
14283 any. If there is no most specialized template, the error_mark_node
14286 Note that this function does not look at, or modify, the
14287 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
14288 returned is one of the elements of INSTANTIATIONS, callers may
14289 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
14290 and retrieve it from the value returned. */
14293 most_specialized_instantiation (tree templates)
14297 ++processing_template_decl;
14300 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
14304 if (get_bindings (TREE_VALUE (champ),
14305 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
14306 NULL_TREE, /*check_ret=*/false))
14309 if (get_bindings (TREE_VALUE (fn),
14310 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
14311 NULL_TREE, /*check_ret=*/false))
14318 /* Equally specialized, move to next function. If there
14319 is no next function, nothing's most specialized. */
14320 fn = TREE_CHAIN (fn);
14328 /* Now verify that champ is better than everything earlier in the
14329 instantiation list. */
14330 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
14331 if (get_bindings (TREE_VALUE (champ),
14332 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
14333 NULL_TREE, /*check_ret=*/false)
14334 || !get_bindings (TREE_VALUE (fn),
14335 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
14336 NULL_TREE, /*check_ret=*/false))
14342 processing_template_decl--;
14345 return error_mark_node;
14350 /* If DECL is a specialization of some template, return the most
14351 general such template. Otherwise, returns NULL_TREE.
14353 For example, given:
14355 template <class T> struct S { template <class U> void f(U); };
14357 if TMPL is `template <class U> void S<int>::f(U)' this will return
14358 the full template. This function will not trace past partial
14359 specializations, however. For example, given in addition:
14361 template <class T> struct S<T*> { template <class U> void f(U); };
14363 if TMPL is `template <class U> void S<int*>::f(U)' this will return
14364 `template <class T> template <class U> S<T*>::f(U)'. */
14367 most_general_template (tree decl)
14369 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
14370 an immediate specialization. */
14371 if (TREE_CODE (decl) == FUNCTION_DECL)
14373 if (DECL_TEMPLATE_INFO (decl)) {
14374 decl = DECL_TI_TEMPLATE (decl);
14376 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
14377 template friend. */
14378 if (TREE_CODE (decl) != TEMPLATE_DECL)
14384 /* Look for more and more general templates. */
14385 while (DECL_TEMPLATE_INFO (decl))
14387 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
14388 (See cp-tree.h for details.) */
14389 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
14392 if (CLASS_TYPE_P (TREE_TYPE (decl))
14393 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
14396 /* Stop if we run into an explicitly specialized class template. */
14397 if (!DECL_NAMESPACE_SCOPE_P (decl)
14398 && DECL_CONTEXT (decl)
14399 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
14402 decl = DECL_TI_TEMPLATE (decl);
14408 /* Return the most specialized of the class template partial
14409 specializations of TMPL which can produce TYPE, a specialization of
14410 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
14411 a _TYPE node corresponding to the partial specialization, while the
14412 TREE_PURPOSE is the set of template arguments that must be
14413 substituted into the TREE_TYPE in order to generate TYPE.
14415 If the choice of partial specialization is ambiguous, a diagnostic
14416 is issued, and the error_mark_node is returned. If there are no
14417 partial specializations of TMPL matching TYPE, then NULL_TREE is
14421 most_specialized_class (tree type, tree tmpl)
14423 tree list = NULL_TREE;
14429 tree outer_args = NULL_TREE;
14431 tmpl = most_general_template (tmpl);
14432 args = CLASSTYPE_TI_ARGS (type);
14434 /* For determining which partial specialization to use, only the
14435 innermost args are interesting. */
14436 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
14438 outer_args = strip_innermost_template_args (args, 1);
14439 args = INNERMOST_TEMPLATE_ARGS (args);
14442 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
14444 tree partial_spec_args;
14446 tree parms = TREE_VALUE (t);
14448 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
14453 ++processing_template_decl;
14455 /* Discard the outer levels of args, and then substitute in the
14456 template args from the enclosing class. */
14457 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
14458 partial_spec_args = tsubst_template_args
14459 (partial_spec_args, outer_args, tf_none, NULL_TREE);
14461 /* PARMS already refers to just the innermost parms, but the
14462 template parms in partial_spec_args had their levels lowered
14463 by tsubst, so we need to do the same for the parm list. We
14464 can't just tsubst the TREE_VEC itself, as tsubst wants to
14465 treat a TREE_VEC as an argument vector. */
14466 parms = copy_node (parms);
14467 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
14468 TREE_VEC_ELT (parms, i) =
14469 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
14471 --processing_template_decl;
14473 spec_args = get_class_bindings (parms,
14479 spec_args = add_to_template_args (outer_args, spec_args);
14480 list = tree_cons (spec_args, TREE_VALUE (t), list);
14481 TREE_TYPE (list) = TREE_TYPE (t);
14488 ambiguous_p = false;
14491 t = TREE_CHAIN (t);
14492 for (; t; t = TREE_CHAIN (t))
14494 fate = more_specialized_class (champ, t);
14501 t = TREE_CHAIN (t);
14504 ambiguous_p = true;
14513 for (t = list; t && t != champ; t = TREE_CHAIN (t))
14515 fate = more_specialized_class (champ, t);
14518 ambiguous_p = true;
14525 const char *str = "candidates are:";
14526 error ("ambiguous class template instantiation for %q#T", type);
14527 for (t = list; t; t = TREE_CHAIN (t))
14529 error ("%s %+#T", str, TREE_TYPE (t));
14532 return error_mark_node;
14538 /* Explicitly instantiate DECL. */
14541 do_decl_instantiation (tree decl, tree storage)
14543 tree result = NULL_TREE;
14546 if (!decl || decl == error_mark_node)
14547 /* An error occurred, for which grokdeclarator has already issued
14548 an appropriate message. */
14550 else if (! DECL_LANG_SPECIFIC (decl))
14552 error ("explicit instantiation of non-template %q#D", decl);
14555 else if (TREE_CODE (decl) == VAR_DECL)
14557 /* There is an asymmetry here in the way VAR_DECLs and
14558 FUNCTION_DECLs are handled by grokdeclarator. In the case of
14559 the latter, the DECL we get back will be marked as a
14560 template instantiation, and the appropriate
14561 DECL_TEMPLATE_INFO will be set up. This does not happen for
14562 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
14563 should handle VAR_DECLs as it currently handles
14565 if (!DECL_CLASS_SCOPE_P (decl))
14567 error ("%qD is not a static data member of a class template", decl);
14570 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
14571 if (!result || TREE_CODE (result) != VAR_DECL)
14573 error ("no matching template for %qD found", decl);
14576 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
14578 error ("type %qT for explicit instantiation %qD does not match "
14579 "declared type %qT", TREE_TYPE (result), decl,
14584 else if (TREE_CODE (decl) != FUNCTION_DECL)
14586 error ("explicit instantiation of %q#D", decl);
14592 /* Check for various error cases. Note that if the explicit
14593 instantiation is valid the RESULT will currently be marked as an
14594 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
14595 until we get here. */
14597 if (DECL_TEMPLATE_SPECIALIZATION (result))
14599 /* DR 259 [temp.spec].
14601 Both an explicit instantiation and a declaration of an explicit
14602 specialization shall not appear in a program unless the explicit
14603 instantiation follows a declaration of the explicit specialization.
14605 For a given set of template parameters, if an explicit
14606 instantiation of a template appears after a declaration of an
14607 explicit specialization for that template, the explicit
14608 instantiation has no effect. */
14611 else if (DECL_EXPLICIT_INSTANTIATION (result))
14615 No program shall explicitly instantiate any template more
14618 We check DECL_NOT_REALLY_EXTERN so as not to complain when
14619 the first instantiation was `extern' and the second is not,
14620 and EXTERN_P for the opposite case. */
14621 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
14622 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
14623 /* If an "extern" explicit instantiation follows an ordinary
14624 explicit instantiation, the template is instantiated. */
14628 else if (!DECL_IMPLICIT_INSTANTIATION (result))
14630 error ("no matching template for %qD found", result);
14633 else if (!DECL_TEMPLATE_INFO (result))
14635 permerror (input_location, "explicit instantiation of non-template %q#D", result);
14639 if (storage == NULL_TREE)
14641 else if (storage == ridpointers[(int) RID_EXTERN])
14643 if (!in_system_header && (cxx_dialect == cxx98))
14644 pedwarn (input_location, OPT_pedantic,
14645 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
14650 error ("storage class %qD applied to template instantiation", storage);
14652 check_explicit_instantiation_namespace (result);
14653 mark_decl_instantiated (result, extern_p);
14655 instantiate_decl (result, /*defer_ok=*/1,
14656 /*expl_inst_class_mem_p=*/false);
14660 mark_class_instantiated (tree t, int extern_p)
14662 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
14663 SET_CLASSTYPE_INTERFACE_KNOWN (t);
14664 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
14665 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
14668 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
14669 rest_of_type_compilation (t, 1);
14673 /* Called from do_type_instantiation through binding_table_foreach to
14674 do recursive instantiation for the type bound in ENTRY. */
14676 bt_instantiate_type_proc (binding_entry entry, void *data)
14678 tree storage = *(tree *) data;
14680 if (MAYBE_CLASS_TYPE_P (entry->type)
14681 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
14682 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
14685 /* Called from do_type_instantiation to instantiate a member
14686 (a member function or a static member variable) of an
14687 explicitly instantiated class template. */
14689 instantiate_class_member (tree decl, int extern_p)
14691 mark_decl_instantiated (decl, extern_p);
14693 instantiate_decl (decl, /*defer_ok=*/1,
14694 /*expl_inst_class_mem_p=*/true);
14697 /* Perform an explicit instantiation of template class T. STORAGE, if
14698 non-null, is the RID for extern, inline or static. COMPLAIN is
14699 nonzero if this is called from the parser, zero if called recursively,
14700 since the standard is unclear (as detailed below). */
14703 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
14708 int previous_instantiation_extern_p = 0;
14710 if (TREE_CODE (t) == TYPE_DECL)
14713 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
14715 error ("explicit instantiation of non-template type %qT", t);
14721 if (!COMPLETE_TYPE_P (t))
14723 if (complain & tf_error)
14724 error ("explicit instantiation of %q#T before definition of template",
14729 if (storage != NULL_TREE)
14731 if (!in_system_header)
14733 if (storage == ridpointers[(int) RID_EXTERN])
14735 if (cxx_dialect == cxx98)
14736 pedwarn (input_location, OPT_pedantic,
14737 "ISO C++ 1998 forbids the use of %<extern%> on "
14738 "explicit instantiations");
14741 pedwarn (input_location, OPT_pedantic,
14742 "ISO C++ forbids the use of %qE"
14743 " on explicit instantiations", storage);
14746 if (storage == ridpointers[(int) RID_INLINE])
14748 else if (storage == ridpointers[(int) RID_EXTERN])
14750 else if (storage == ridpointers[(int) RID_STATIC])
14754 error ("storage class %qD applied to template instantiation",
14760 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
14762 /* DR 259 [temp.spec].
14764 Both an explicit instantiation and a declaration of an explicit
14765 specialization shall not appear in a program unless the explicit
14766 instantiation follows a declaration of the explicit specialization.
14768 For a given set of template parameters, if an explicit
14769 instantiation of a template appears after a declaration of an
14770 explicit specialization for that template, the explicit
14771 instantiation has no effect. */
14774 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
14778 No program shall explicitly instantiate any template more
14781 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
14782 instantiation was `extern'. If EXTERN_P then the second is.
14783 These cases are OK. */
14784 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
14786 if (!previous_instantiation_extern_p && !extern_p
14787 && (complain & tf_error))
14788 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
14790 /* If we've already instantiated the template, just return now. */
14791 if (!CLASSTYPE_INTERFACE_ONLY (t))
14795 check_explicit_instantiation_namespace (TYPE_NAME (t));
14796 mark_class_instantiated (t, extern_p);
14804 /* In contrast to implicit instantiation, where only the
14805 declarations, and not the definitions, of members are
14806 instantiated, we have here:
14810 The explicit instantiation of a class template specialization
14811 implies the instantiation of all of its members not
14812 previously explicitly specialized in the translation unit
14813 containing the explicit instantiation.
14815 Of course, we can't instantiate member template classes, since
14816 we don't have any arguments for them. Note that the standard
14817 is unclear on whether the instantiation of the members are
14818 *explicit* instantiations or not. However, the most natural
14819 interpretation is that it should be an explicit instantiation. */
14822 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
14823 if (TREE_CODE (tmp) == FUNCTION_DECL
14824 && DECL_TEMPLATE_INSTANTIATION (tmp))
14825 instantiate_class_member (tmp, extern_p);
14827 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
14828 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
14829 instantiate_class_member (tmp, extern_p);
14831 if (CLASSTYPE_NESTED_UTDS (t))
14832 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
14833 bt_instantiate_type_proc, &storage);
14837 /* Given a function DECL, which is a specialization of TMPL, modify
14838 DECL to be a re-instantiation of TMPL with the same template
14839 arguments. TMPL should be the template into which tsubst'ing
14840 should occur for DECL, not the most general template.
14842 One reason for doing this is a scenario like this:
14845 void f(const T&, int i);
14847 void g() { f(3, 7); }
14850 void f(const T& t, const int i) { }
14852 Note that when the template is first instantiated, with
14853 instantiate_template, the resulting DECL will have no name for the
14854 first parameter, and the wrong type for the second. So, when we go
14855 to instantiate the DECL, we regenerate it. */
14858 regenerate_decl_from_template (tree decl, tree tmpl)
14860 /* The arguments used to instantiate DECL, from the most general
14865 args = DECL_TI_ARGS (decl);
14866 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
14868 /* Make sure that we can see identifiers, and compute access
14870 push_access_scope (decl);
14872 if (TREE_CODE (decl) == FUNCTION_DECL)
14880 args_depth = TMPL_ARGS_DEPTH (args);
14881 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
14882 if (args_depth > parms_depth)
14883 args = get_innermost_template_args (args, parms_depth);
14885 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
14886 args, tf_error, NULL_TREE);
14888 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
14891 /* Merge parameter declarations. */
14892 decl_parm = skip_artificial_parms_for (decl,
14893 DECL_ARGUMENTS (decl));
14895 = skip_artificial_parms_for (code_pattern,
14896 DECL_ARGUMENTS (code_pattern));
14897 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
14902 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
14903 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
14904 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
14906 parm_type = type_decays_to (parm_type);
14907 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
14908 TREE_TYPE (decl_parm) = parm_type;
14909 attributes = DECL_ATTRIBUTES (pattern_parm);
14910 if (DECL_ATTRIBUTES (decl_parm) != attributes)
14912 DECL_ATTRIBUTES (decl_parm) = attributes;
14913 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
14915 decl_parm = TREE_CHAIN (decl_parm);
14916 pattern_parm = TREE_CHAIN (pattern_parm);
14918 /* Merge any parameters that match with the function parameter
14920 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
14923 tree expanded_types;
14924 /* Expand the TYPE_PACK_EXPANSION that provides the types for
14925 the parameters in this function parameter pack. */
14926 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
14927 args, tf_error, NULL_TREE);
14928 len = TREE_VEC_LENGTH (expanded_types);
14929 for (i = 0; i < len; i++)
14934 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
14935 /* Rename the parameter to include the index. */
14936 DECL_NAME (decl_parm) =
14937 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
14938 parm_type = TREE_VEC_ELT (expanded_types, i);
14939 parm_type = type_decays_to (parm_type);
14940 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
14941 TREE_TYPE (decl_parm) = parm_type;
14942 attributes = DECL_ATTRIBUTES (pattern_parm);
14943 if (DECL_ATTRIBUTES (decl_parm) != attributes)
14945 DECL_ATTRIBUTES (decl_parm) = attributes;
14946 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
14948 decl_parm = TREE_CHAIN (decl_parm);
14951 /* Merge additional specifiers from the CODE_PATTERN. */
14952 if (DECL_DECLARED_INLINE_P (code_pattern)
14953 && !DECL_DECLARED_INLINE_P (decl))
14954 DECL_DECLARED_INLINE_P (decl) = 1;
14956 else if (TREE_CODE (decl) == VAR_DECL)
14957 DECL_INITIAL (decl) =
14958 tsubst_expr (DECL_INITIAL (code_pattern), args,
14959 tf_error, DECL_TI_TEMPLATE (decl),
14960 /*integral_constant_expression_p=*/false);
14962 gcc_unreachable ();
14964 pop_access_scope (decl);
14967 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
14968 substituted to get DECL. */
14971 template_for_substitution (tree decl)
14973 tree tmpl = DECL_TI_TEMPLATE (decl);
14975 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
14976 for the instantiation. This is not always the most general
14977 template. Consider, for example:
14980 struct S { template <class U> void f();
14981 template <> void f<int>(); };
14983 and an instantiation of S<double>::f<int>. We want TD to be the
14984 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
14985 while (/* An instantiation cannot have a definition, so we need a
14986 more general template. */
14987 DECL_TEMPLATE_INSTANTIATION (tmpl)
14988 /* We must also deal with friend templates. Given:
14990 template <class T> struct S {
14991 template <class U> friend void f() {};
14994 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
14995 so far as the language is concerned, but that's still
14996 where we get the pattern for the instantiation from. On
14997 other hand, if the definition comes outside the class, say:
14999 template <class T> struct S {
15000 template <class U> friend void f();
15002 template <class U> friend void f() {}
15004 we don't need to look any further. That's what the check for
15005 DECL_INITIAL is for. */
15006 || (TREE_CODE (decl) == FUNCTION_DECL
15007 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
15008 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
15010 /* The present template, TD, should not be a definition. If it
15011 were a definition, we should be using it! Note that we
15012 cannot restructure the loop to just keep going until we find
15013 a template with a definition, since that might go too far if
15014 a specialization was declared, but not defined. */
15015 gcc_assert (TREE_CODE (decl) != VAR_DECL
15016 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
15018 /* Fetch the more general template. */
15019 tmpl = DECL_TI_TEMPLATE (tmpl);
15025 /* Produce the definition of D, a _DECL generated from a template. If
15026 DEFER_OK is nonzero, then we don't have to actually do the
15027 instantiation now; we just have to do it sometime. Normally it is
15028 an error if this is an explicit instantiation but D is undefined.
15029 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
15030 explicitly instantiated class template. */
15033 instantiate_decl (tree d, int defer_ok,
15034 bool expl_inst_class_mem_p)
15036 tree tmpl = DECL_TI_TEMPLATE (d);
15043 bool pattern_defined;
15045 location_t saved_loc = input_location;
15048 /* This function should only be used to instantiate templates for
15049 functions and static member variables. */
15050 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
15051 || TREE_CODE (d) == VAR_DECL);
15053 /* Variables are never deferred; if instantiation is required, they
15054 are instantiated right away. That allows for better code in the
15055 case that an expression refers to the value of the variable --
15056 if the variable has a constant value the referring expression can
15057 take advantage of that fact. */
15058 if (TREE_CODE (d) == VAR_DECL)
15061 /* Don't instantiate cloned functions. Instead, instantiate the
15062 functions they cloned. */
15063 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
15064 d = DECL_CLONED_FUNCTION (d);
15066 if (DECL_TEMPLATE_INSTANTIATED (d))
15067 /* D has already been instantiated. It might seem reasonable to
15068 check whether or not D is an explicit instantiation, and, if so,
15069 stop here. But when an explicit instantiation is deferred
15070 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
15071 is set, even though we still need to do the instantiation. */
15074 /* If we already have a specialization of this declaration, then
15075 there's no reason to instantiate it. Note that
15076 retrieve_specialization gives us both instantiations and
15077 specializations, so we must explicitly check
15078 DECL_TEMPLATE_SPECIALIZATION. */
15079 gen_tmpl = most_general_template (tmpl);
15080 gen_args = DECL_TI_ARGS (d);
15081 spec = retrieve_specialization (gen_tmpl, gen_args,
15082 /*class_specializations_p=*/false);
15083 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
15086 /* This needs to happen before any tsubsting. */
15087 if (! push_tinst_level (d))
15090 timevar_push (TV_PARSE);
15092 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
15093 for the instantiation. */
15094 td = template_for_substitution (d);
15095 code_pattern = DECL_TEMPLATE_RESULT (td);
15097 /* We should never be trying to instantiate a member of a class
15098 template or partial specialization. */
15099 gcc_assert (d != code_pattern);
15101 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
15102 || DECL_TEMPLATE_SPECIALIZATION (td))
15103 /* In the case of a friend template whose definition is provided
15104 outside the class, we may have too many arguments. Drop the
15105 ones we don't need. The same is true for specializations. */
15106 args = get_innermost_template_args
15107 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
15111 if (TREE_CODE (d) == FUNCTION_DECL)
15112 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
15114 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
15116 /* We may be in the middle of deferred access check. Disable it now. */
15117 push_deferring_access_checks (dk_no_deferred);
15119 /* Unless an explicit instantiation directive has already determined
15120 the linkage of D, remember that a definition is available for
15122 if (pattern_defined
15123 && !DECL_INTERFACE_KNOWN (d)
15124 && !DECL_NOT_REALLY_EXTERN (d))
15125 mark_definable (d);
15127 input_location = DECL_SOURCE_LOCATION (d);
15129 /* If D is a member of an explicitly instantiated class template,
15130 and no definition is available, treat it like an implicit
15132 if (!pattern_defined && expl_inst_class_mem_p
15133 && DECL_EXPLICIT_INSTANTIATION (d))
15135 DECL_NOT_REALLY_EXTERN (d) = 0;
15136 DECL_INTERFACE_KNOWN (d) = 0;
15137 SET_DECL_IMPLICIT_INSTANTIATION (d);
15142 /* Recheck the substitutions to obtain any warning messages
15143 about ignoring cv qualifiers. */
15144 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
15145 tree type = TREE_TYPE (gen);
15147 /* Make sure that we can see identifiers, and compute access
15148 correctly. D is already the target FUNCTION_DECL with the
15150 push_access_scope (d);
15152 if (TREE_CODE (gen) == FUNCTION_DECL)
15154 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
15155 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
15157 /* Don't simply tsubst the function type, as that will give
15158 duplicate warnings about poor parameter qualifications.
15159 The function arguments are the same as the decl_arguments
15160 without the top level cv qualifiers. */
15161 type = TREE_TYPE (type);
15163 tsubst (type, gen_args, tf_warning_or_error, d);
15165 pop_access_scope (d);
15168 /* Check to see whether we know that this template will be
15169 instantiated in some other file, as with "extern template"
15171 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
15172 /* In general, we do not instantiate such templates... */
15174 /* ... but we instantiate inline functions so that we can inline
15176 && ! (TREE_CODE (d) == FUNCTION_DECL
15177 && possibly_inlined_p (d))
15178 /* ... we instantiate static data members whose values are
15179 needed in integral constant expressions. */
15180 && ! (TREE_CODE (d) == VAR_DECL
15181 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
15183 /* Defer all other templates, unless we have been explicitly
15184 forbidden from doing so. */
15185 if (/* If there is no definition, we cannot instantiate the
15188 /* If it's OK to postpone instantiation, do so. */
15190 /* If this is a static data member that will be defined
15191 elsewhere, we don't want to instantiate the entire data
15192 member, but we do want to instantiate the initializer so that
15193 we can substitute that elsewhere. */
15194 || (external_p && TREE_CODE (d) == VAR_DECL))
15196 /* The definition of the static data member is now required so
15197 we must substitute the initializer. */
15198 if (TREE_CODE (d) == VAR_DECL
15199 && !DECL_INITIAL (d)
15200 && DECL_INITIAL (code_pattern))
15205 ns = decl_namespace_context (d);
15206 push_nested_namespace (ns);
15207 push_nested_class (DECL_CONTEXT (d));
15208 init = tsubst_expr (DECL_INITIAL (code_pattern),
15210 tf_warning_or_error, NULL_TREE,
15211 /*integral_constant_expression_p=*/false);
15212 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
15213 /*asmspec_tree=*/NULL_TREE,
15214 LOOKUP_ONLYCONVERTING);
15215 pop_nested_class ();
15216 pop_nested_namespace (ns);
15219 /* We restore the source position here because it's used by
15220 add_pending_template. */
15221 input_location = saved_loc;
15223 if (at_eof && !pattern_defined
15224 && DECL_EXPLICIT_INSTANTIATION (d))
15227 The definition of a non-exported function template, a
15228 non-exported member function template, or a non-exported
15229 member function or static data member of a class template
15230 shall be present in every translation unit in which it is
15231 explicitly instantiated. */
15232 permerror (input_location, "explicit instantiation of %qD "
15233 "but no definition available", d);
15235 /* ??? Historically, we have instantiated inline functions, even
15236 when marked as "extern template". */
15237 if (!(external_p && TREE_CODE (d) == VAR_DECL))
15238 add_pending_template (d);
15241 /* Tell the repository that D is available in this translation unit
15242 -- and see if it is supposed to be instantiated here. */
15243 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
15245 /* In a PCH file, despite the fact that the repository hasn't
15246 requested instantiation in the PCH it is still possible that
15247 an instantiation will be required in a file that includes the
15250 add_pending_template (d);
15251 /* Instantiate inline functions so that the inliner can do its
15252 job, even though we'll not be emitting a copy of this
15254 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
15258 need_push = !cfun || !global_bindings_p ();
15260 push_to_top_level ();
15262 /* Mark D as instantiated so that recursive calls to
15263 instantiate_decl do not try to instantiate it again. */
15264 DECL_TEMPLATE_INSTANTIATED (d) = 1;
15266 /* Regenerate the declaration in case the template has been modified
15267 by a subsequent redeclaration. */
15268 regenerate_decl_from_template (d, td);
15270 /* We already set the file and line above. Reset them now in case
15271 they changed as a result of calling regenerate_decl_from_template. */
15272 input_location = DECL_SOURCE_LOCATION (d);
15274 if (TREE_CODE (d) == VAR_DECL)
15278 /* Clear out DECL_RTL; whatever was there before may not be right
15279 since we've reset the type of the declaration. */
15280 SET_DECL_RTL (d, NULL_RTX);
15281 DECL_IN_AGGR_P (d) = 0;
15283 /* The initializer is placed in DECL_INITIAL by
15284 regenerate_decl_from_template. Pull it out so that
15285 finish_decl can process it. */
15286 init = DECL_INITIAL (d);
15287 DECL_INITIAL (d) = NULL_TREE;
15288 DECL_INITIALIZED_P (d) = 0;
15290 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
15291 initializer. That function will defer actual emission until
15292 we have a chance to determine linkage. */
15293 DECL_EXTERNAL (d) = 0;
15295 /* Enter the scope of D so that access-checking works correctly. */
15296 push_nested_class (DECL_CONTEXT (d));
15297 finish_decl (d, init, NULL_TREE);
15298 pop_nested_class ();
15300 else if (TREE_CODE (d) == FUNCTION_DECL)
15302 htab_t saved_local_specializations;
15307 /* Save away the current list, in case we are instantiating one
15308 template from within the body of another. */
15309 saved_local_specializations = local_specializations;
15311 /* Set up the list of local specializations. */
15312 local_specializations = htab_create (37,
15313 hash_local_specialization,
15314 eq_local_specializations,
15317 /* Set up context. */
15318 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
15320 /* Create substitution entries for the parameters. */
15321 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
15322 tmpl_parm = DECL_ARGUMENTS (subst_decl);
15323 spec_parm = DECL_ARGUMENTS (d);
15324 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
15326 register_local_specialization (spec_parm, tmpl_parm);
15327 spec_parm = skip_artificial_parms_for (d, spec_parm);
15328 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
15330 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
15332 register_local_specialization (spec_parm, tmpl_parm);
15333 tmpl_parm = TREE_CHAIN (tmpl_parm);
15334 spec_parm = TREE_CHAIN (spec_parm);
15336 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
15338 /* Collect all of the extra "packed" parameters into an
15342 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
15343 tree argtypepack = make_node (TYPE_ARGUMENT_PACK);
15347 /* Count how many parameters remain. */
15348 for (t = spec_parm; t; t = TREE_CHAIN (t))
15351 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
15352 parmvec = make_tree_vec (len);
15353 parmtypevec = make_tree_vec (len);
15354 for(i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
15356 TREE_VEC_ELT (parmvec, i) = spec_parm;
15357 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
15360 /* Build the argument packs. */
15361 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
15362 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
15363 TREE_TYPE (argpack) = argtypepack;
15365 /* Register the (value) argument pack as a specialization of
15366 TMPL_PARM, then move on. */
15367 register_local_specialization (argpack, tmpl_parm);
15368 tmpl_parm = TREE_CHAIN (tmpl_parm);
15370 gcc_assert (!spec_parm);
15372 /* Substitute into the body of the function. */
15373 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
15374 tf_warning_or_error, tmpl,
15375 /*integral_constant_expression_p=*/false);
15377 /* Set the current input_location to the end of the function
15378 so that finish_function knows where we are. */
15379 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
15381 /* We don't need the local specializations any more. */
15382 htab_delete (local_specializations);
15383 local_specializations = saved_local_specializations;
15385 /* Finish the function. */
15386 d = finish_function (0);
15387 expand_or_defer_fn (d);
15390 /* We're not deferring instantiation any more. */
15391 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
15394 pop_from_top_level ();
15397 input_location = saved_loc;
15398 pop_deferring_access_checks ();
15399 pop_tinst_level ();
15401 timevar_pop (TV_PARSE);
15406 /* Run through the list of templates that we wish we could
15407 instantiate, and instantiate any we can. RETRIES is the
15408 number of times we retry pending template instantiation. */
15411 instantiate_pending_templates (int retries)
15414 location_t saved_loc = input_location;
15416 /* Instantiating templates may trigger vtable generation. This in turn
15417 may require further template instantiations. We place a limit here
15418 to avoid infinite loop. */
15419 if (pending_templates && retries >= max_tinst_depth)
15421 tree decl = pending_templates->tinst->decl;
15423 error ("template instantiation depth exceeds maximum of %d"
15424 " instantiating %q+D, possibly from virtual table generation"
15425 " (use -ftemplate-depth-NN to increase the maximum)",
15426 max_tinst_depth, decl);
15427 if (TREE_CODE (decl) == FUNCTION_DECL)
15428 /* Pretend that we defined it. */
15429 DECL_INITIAL (decl) = error_mark_node;
15435 struct pending_template **t = &pending_templates;
15436 struct pending_template *last = NULL;
15440 tree instantiation = reopen_tinst_level ((*t)->tinst);
15441 bool complete = false;
15443 if (TYPE_P (instantiation))
15447 if (!COMPLETE_TYPE_P (instantiation))
15449 instantiate_class_template (instantiation);
15450 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
15451 for (fn = TYPE_METHODS (instantiation);
15453 fn = TREE_CHAIN (fn))
15454 if (! DECL_ARTIFICIAL (fn))
15455 instantiate_decl (fn,
15457 /*expl_inst_class_mem_p=*/false);
15458 if (COMPLETE_TYPE_P (instantiation))
15462 complete = COMPLETE_TYPE_P (instantiation);
15466 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
15467 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
15470 = instantiate_decl (instantiation,
15472 /*expl_inst_class_mem_p=*/false);
15473 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
15477 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
15478 || DECL_TEMPLATE_INSTANTIATED (instantiation));
15482 /* If INSTANTIATION has been instantiated, then we don't
15483 need to consider it again in the future. */
15491 current_tinst_level = NULL;
15493 last_pending_template = last;
15495 while (reconsider);
15497 input_location = saved_loc;
15500 /* Substitute ARGVEC into T, which is a list of initializers for
15501 either base class or a non-static data member. The TREE_PURPOSEs
15502 are DECLs, and the TREE_VALUEs are the initializer values. Used by
15503 instantiate_decl. */
15506 tsubst_initializer_list (tree t, tree argvec)
15508 tree inits = NULL_TREE;
15510 for (; t; t = TREE_CHAIN (t))
15514 tree expanded_bases = NULL_TREE;
15515 tree expanded_arguments = NULL_TREE;
15518 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
15523 /* Expand the base class expansion type into separate base
15525 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
15526 tf_warning_or_error,
15528 if (expanded_bases == error_mark_node)
15531 /* We'll be building separate TREE_LISTs of arguments for
15533 len = TREE_VEC_LENGTH (expanded_bases);
15534 expanded_arguments = make_tree_vec (len);
15535 for (i = 0; i < len; i++)
15536 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
15538 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
15539 expand each argument in the TREE_VALUE of t. */
15540 expr = make_node (EXPR_PACK_EXPANSION);
15541 PACK_EXPANSION_PARAMETER_PACKS (expr) =
15542 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
15544 if (TREE_VALUE (t) == void_type_node)
15545 /* VOID_TYPE_NODE is used to indicate
15546 value-initialization. */
15548 for (i = 0; i < len; i++)
15549 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
15553 /* Substitute parameter packs into each argument in the
15555 in_base_initializer = 1;
15556 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
15558 tree expanded_exprs;
15560 /* Expand the argument. */
15561 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
15563 = tsubst_pack_expansion (expr, argvec,
15564 tf_warning_or_error,
15566 if (expanded_exprs == error_mark_node)
15569 /* Prepend each of the expanded expressions to the
15570 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
15571 for (i = 0; i < len; i++)
15573 TREE_VEC_ELT (expanded_arguments, i) =
15574 tree_cons (NULL_TREE,
15575 TREE_VEC_ELT (expanded_exprs, i),
15576 TREE_VEC_ELT (expanded_arguments, i));
15579 in_base_initializer = 0;
15581 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
15582 since we built them backwards. */
15583 for (i = 0; i < len; i++)
15585 TREE_VEC_ELT (expanded_arguments, i) =
15586 nreverse (TREE_VEC_ELT (expanded_arguments, i));
15591 for (i = 0; i < len; ++i)
15593 if (expanded_bases)
15595 decl = TREE_VEC_ELT (expanded_bases, i);
15596 decl = expand_member_init (decl);
15597 init = TREE_VEC_ELT (expanded_arguments, i);
15601 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
15602 tf_warning_or_error, NULL_TREE);
15604 decl = expand_member_init (decl);
15605 if (decl && !DECL_P (decl))
15606 in_base_initializer = 1;
15608 init = tsubst_expr (TREE_VALUE (t), argvec,
15609 tf_warning_or_error, NULL_TREE,
15610 /*integral_constant_expression_p=*/false);
15611 in_base_initializer = 0;
15616 init = build_tree_list (decl, init);
15617 TREE_CHAIN (init) = inits;
15625 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
15628 set_current_access_from_decl (tree decl)
15630 if (TREE_PRIVATE (decl))
15631 current_access_specifier = access_private_node;
15632 else if (TREE_PROTECTED (decl))
15633 current_access_specifier = access_protected_node;
15635 current_access_specifier = access_public_node;
15638 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
15639 is the instantiation (which should have been created with
15640 start_enum) and ARGS are the template arguments to use. */
15643 tsubst_enum (tree tag, tree newtag, tree args)
15647 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
15652 decl = TREE_VALUE (e);
15653 /* Note that in a template enum, the TREE_VALUE is the
15654 CONST_DECL, not the corresponding INTEGER_CST. */
15655 value = tsubst_expr (DECL_INITIAL (decl),
15656 args, tf_warning_or_error, NULL_TREE,
15657 /*integral_constant_expression_p=*/true);
15659 /* Give this enumeration constant the correct access. */
15660 set_current_access_from_decl (decl);
15662 /* Actually build the enumerator itself. */
15663 build_enumerator (DECL_NAME (decl), value, newtag);
15666 finish_enum (newtag);
15667 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
15668 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
15671 /* DECL is a FUNCTION_DECL that is a template specialization. Return
15672 its type -- but without substituting the innermost set of template
15673 arguments. So, innermost set of template parameters will appear in
15677 get_mostly_instantiated_function_type (tree decl)
15685 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
15686 targs = DECL_TI_ARGS (decl);
15687 tparms = DECL_TEMPLATE_PARMS (tmpl);
15688 parm_depth = TMPL_PARMS_DEPTH (tparms);
15690 /* There should be as many levels of arguments as there are levels
15692 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
15694 fn_type = TREE_TYPE (tmpl);
15696 if (parm_depth == 1)
15697 /* No substitution is necessary. */
15701 int i, save_access_control;
15704 /* Replace the innermost level of the TARGS with NULL_TREEs to
15705 let tsubst know not to substitute for those parameters. */
15706 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
15707 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
15708 SET_TMPL_ARGS_LEVEL (partial_args, i,
15709 TMPL_ARGS_LEVEL (targs, i));
15710 SET_TMPL_ARGS_LEVEL (partial_args,
15711 TMPL_ARGS_DEPTH (targs),
15712 make_tree_vec (DECL_NTPARMS (tmpl)));
15714 /* Disable access control as this function is used only during
15716 save_access_control = flag_access_control;
15717 flag_access_control = 0;
15719 ++processing_template_decl;
15720 /* Now, do the (partial) substitution to figure out the
15721 appropriate function type. */
15722 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
15723 --processing_template_decl;
15725 /* Substitute into the template parameters to obtain the real
15726 innermost set of parameters. This step is important if the
15727 innermost set of template parameters contains value
15728 parameters whose types depend on outer template parameters. */
15729 TREE_VEC_LENGTH (partial_args)--;
15730 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
15732 flag_access_control = save_access_control;
15738 /* Return truthvalue if we're processing a template different from
15739 the last one involved in diagnostics. */
15741 problematic_instantiation_changed (void)
15743 return last_template_error_tick != tinst_level_tick;
15746 /* Remember current template involved in diagnostics. */
15748 record_last_problematic_instantiation (void)
15750 last_template_error_tick = tinst_level_tick;
15753 struct tinst_level *
15754 current_instantiation (void)
15756 return current_tinst_level;
15759 /* [temp.param] Check that template non-type parm TYPE is of an allowable
15760 type. Return zero for ok, nonzero for disallowed. Issue error and
15761 warning messages under control of COMPLAIN. */
15764 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
15766 if (INTEGRAL_TYPE_P (type))
15768 else if (POINTER_TYPE_P (type))
15770 else if (TYPE_PTR_TO_MEMBER_P (type))
15772 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
15774 else if (TREE_CODE (type) == TYPENAME_TYPE)
15777 if (complain & tf_error)
15778 error ("%q#T is not a valid type for a template constant parameter", type);
15782 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
15783 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
15786 dependent_type_p_r (tree type)
15792 A type is dependent if it is:
15794 -- a template parameter. Template template parameters are types
15795 for us (since TYPE_P holds true for them) so we handle
15797 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
15798 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
15800 /* -- a qualified-id with a nested-name-specifier which contains a
15801 class-name that names a dependent type or whose unqualified-id
15802 names a dependent type. */
15803 if (TREE_CODE (type) == TYPENAME_TYPE)
15805 /* -- a cv-qualified type where the cv-unqualified type is
15807 type = TYPE_MAIN_VARIANT (type);
15808 /* -- a compound type constructed from any dependent type. */
15809 if (TYPE_PTR_TO_MEMBER_P (type))
15810 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
15811 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
15813 else if (TREE_CODE (type) == POINTER_TYPE
15814 || TREE_CODE (type) == REFERENCE_TYPE)
15815 return dependent_type_p (TREE_TYPE (type));
15816 else if (TREE_CODE (type) == FUNCTION_TYPE
15817 || TREE_CODE (type) == METHOD_TYPE)
15821 if (dependent_type_p (TREE_TYPE (type)))
15823 for (arg_type = TYPE_ARG_TYPES (type);
15825 arg_type = TREE_CHAIN (arg_type))
15826 if (dependent_type_p (TREE_VALUE (arg_type)))
15830 /* -- an array type constructed from any dependent type or whose
15831 size is specified by a constant expression that is
15832 value-dependent. */
15833 if (TREE_CODE (type) == ARRAY_TYPE)
15835 if (TYPE_DOMAIN (type)
15836 && dependent_type_p (TYPE_DOMAIN (type)))
15838 return dependent_type_p (TREE_TYPE (type));
15840 else if (TREE_CODE (type) == INTEGER_TYPE
15841 && !TREE_CONSTANT (TYPE_MAX_VALUE (type)))
15843 /* If this is the TYPE_DOMAIN of an array type, consider it
15845 return (value_dependent_expression_p (TYPE_MAX_VALUE (type))
15846 || type_dependent_expression_p (TYPE_MAX_VALUE (type)));
15849 /* -- a template-id in which either the template name is a template
15851 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
15853 /* ... or any of the template arguments is a dependent type or
15854 an expression that is type-dependent or value-dependent. */
15855 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
15856 && (any_dependent_template_arguments_p
15857 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
15860 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
15861 argument of the `typeof' expression is not type-dependent, then
15862 it should already been have resolved. */
15863 if (TREE_CODE (type) == TYPEOF_TYPE
15864 || TREE_CODE (type) == DECLTYPE_TYPE)
15867 /* A template argument pack is dependent if any of its packed
15869 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
15871 tree args = ARGUMENT_PACK_ARGS (type);
15872 int i, len = TREE_VEC_LENGTH (args);
15873 for (i = 0; i < len; ++i)
15874 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
15878 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
15879 be template parameters. */
15880 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
15883 /* The standard does not specifically mention types that are local
15884 to template functions or local classes, but they should be
15885 considered dependent too. For example:
15887 template <int I> void f() {
15892 The size of `E' cannot be known until the value of `I' has been
15893 determined. Therefore, `E' must be considered dependent. */
15894 scope = TYPE_CONTEXT (type);
15895 if (scope && TYPE_P (scope))
15896 return dependent_type_p (scope);
15897 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
15898 return type_dependent_expression_p (scope);
15900 /* Other types are non-dependent. */
15904 /* Returns TRUE if TYPE is dependent, in the sense of
15905 [temp.dep.type]. */
15908 dependent_type_p (tree type)
15910 /* If there are no template parameters in scope, then there can't be
15911 any dependent types. */
15912 if (!processing_template_decl)
15914 /* If we are not processing a template, then nobody should be
15915 providing us with a dependent type. */
15917 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
15921 /* If the type is NULL, we have not computed a type for the entity
15922 in question; in that case, the type is dependent. */
15926 /* Erroneous types can be considered non-dependent. */
15927 if (type == error_mark_node)
15930 /* If we have not already computed the appropriate value for TYPE,
15932 if (!TYPE_DEPENDENT_P_VALID (type))
15934 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
15935 TYPE_DEPENDENT_P_VALID (type) = 1;
15938 return TYPE_DEPENDENT_P (type);
15941 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
15944 dependent_scope_ref_p (tree expression, bool criterion (tree))
15949 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
15951 if (!TYPE_P (TREE_OPERAND (expression, 0)))
15954 scope = TREE_OPERAND (expression, 0);
15955 name = TREE_OPERAND (expression, 1);
15959 An id-expression is type-dependent if it contains a
15960 nested-name-specifier that contains a class-name that names a
15962 /* The suggested resolution to Core Issue 2 implies that if the
15963 qualifying type is the current class, then we must peek
15966 && currently_open_class (scope)
15967 && !criterion (name))
15969 if (dependent_type_p (scope))
15975 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
15976 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
15980 value_dependent_expression_p (tree expression)
15982 if (!processing_template_decl)
15985 /* A name declared with a dependent type. */
15986 if (DECL_P (expression) && type_dependent_expression_p (expression))
15989 switch (TREE_CODE (expression))
15991 case IDENTIFIER_NODE:
15992 /* A name that has not been looked up -- must be dependent. */
15995 case TEMPLATE_PARM_INDEX:
15996 /* A non-type template parm. */
16000 /* A non-type template parm. */
16001 if (DECL_TEMPLATE_PARM_P (expression))
16003 return value_dependent_expression_p (DECL_INITIAL (expression));
16006 /* A constant with integral or enumeration type and is initialized
16007 with an expression that is value-dependent. */
16008 if (DECL_INITIAL (expression)
16009 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
16010 && value_dependent_expression_p (DECL_INITIAL (expression)))
16014 case DYNAMIC_CAST_EXPR:
16015 case STATIC_CAST_EXPR:
16016 case CONST_CAST_EXPR:
16017 case REINTERPRET_CAST_EXPR:
16019 /* These expressions are value-dependent if the type to which
16020 the cast occurs is dependent or the expression being casted
16021 is value-dependent. */
16023 tree type = TREE_TYPE (expression);
16025 if (dependent_type_p (type))
16028 /* A functional cast has a list of operands. */
16029 expression = TREE_OPERAND (expression, 0);
16032 /* If there are no operands, it must be an expression such
16033 as "int()". This should not happen for aggregate types
16034 because it would form non-constant expressions. */
16035 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
16040 if (TREE_CODE (expression) == TREE_LIST)
16041 return any_value_dependent_elements_p (expression);
16043 return value_dependent_expression_p (expression);
16048 /* A `sizeof' expression is value-dependent if the operand is
16049 type-dependent or is a pack expansion. */
16050 expression = TREE_OPERAND (expression, 0);
16051 if (PACK_EXPANSION_P (expression))
16053 else if (TYPE_P (expression))
16054 return dependent_type_p (expression);
16055 return type_dependent_expression_p (expression);
16058 return dependent_scope_ref_p (expression, value_dependent_expression_p);
16060 case COMPONENT_REF:
16061 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
16062 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
16065 /* A CALL_EXPR may appear in a constant expression if it is a
16066 call to a builtin function, e.g., __builtin_constant_p. All
16067 such calls are value-dependent. */
16070 case NONTYPE_ARGUMENT_PACK:
16071 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
16072 is value-dependent. */
16074 tree values = ARGUMENT_PACK_ARGS (expression);
16075 int i, len = TREE_VEC_LENGTH (values);
16077 for (i = 0; i < len; ++i)
16078 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
16086 tree type2 = TRAIT_EXPR_TYPE2 (expression);
16087 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
16088 || (type2 ? dependent_type_p (type2) : false));
16092 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
16093 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
16096 /* A constant expression is value-dependent if any subexpression is
16097 value-dependent. */
16098 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
16100 case tcc_reference:
16102 return (value_dependent_expression_p
16103 (TREE_OPERAND (expression, 0)));
16105 case tcc_comparison:
16107 return ((value_dependent_expression_p
16108 (TREE_OPERAND (expression, 0)))
16109 || (value_dependent_expression_p
16110 (TREE_OPERAND (expression, 1))));
16112 case tcc_expression:
16116 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
16117 /* In some cases, some of the operands may be missing.
16118 (For example, in the case of PREDECREMENT_EXPR, the
16119 amount to increment by may be missing.) That doesn't
16120 make the expression dependent. */
16121 if (TREE_OPERAND (expression, i)
16122 && (value_dependent_expression_p
16123 (TREE_OPERAND (expression, i))))
16133 /* The expression is not value-dependent. */
16137 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
16138 [temp.dep.expr]. */
16141 type_dependent_expression_p (tree expression)
16143 if (!processing_template_decl)
16146 if (expression == error_mark_node)
16149 /* An unresolved name is always dependent. */
16150 if (TREE_CODE (expression) == IDENTIFIER_NODE
16151 || TREE_CODE (expression) == USING_DECL)
16154 /* Some expression forms are never type-dependent. */
16155 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
16156 || TREE_CODE (expression) == SIZEOF_EXPR
16157 || TREE_CODE (expression) == ALIGNOF_EXPR
16158 || TREE_CODE (expression) == TRAIT_EXPR
16159 || TREE_CODE (expression) == TYPEID_EXPR
16160 || TREE_CODE (expression) == DELETE_EXPR
16161 || TREE_CODE (expression) == VEC_DELETE_EXPR
16162 || TREE_CODE (expression) == THROW_EXPR)
16165 /* The types of these expressions depends only on the type to which
16166 the cast occurs. */
16167 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
16168 || TREE_CODE (expression) == STATIC_CAST_EXPR
16169 || TREE_CODE (expression) == CONST_CAST_EXPR
16170 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
16171 || TREE_CODE (expression) == CAST_EXPR)
16172 return dependent_type_p (TREE_TYPE (expression));
16174 /* The types of these expressions depends only on the type created
16175 by the expression. */
16176 if (TREE_CODE (expression) == NEW_EXPR
16177 || TREE_CODE (expression) == VEC_NEW_EXPR)
16179 /* For NEW_EXPR tree nodes created inside a template, either
16180 the object type itself or a TREE_LIST may appear as the
16182 tree type = TREE_OPERAND (expression, 1);
16183 if (TREE_CODE (type) == TREE_LIST)
16184 /* This is an array type. We need to check array dimensions
16186 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
16187 || value_dependent_expression_p
16188 (TREE_OPERAND (TREE_VALUE (type), 1));
16190 return dependent_type_p (type);
16193 if (TREE_CODE (expression) == SCOPE_REF
16194 && dependent_scope_ref_p (expression,
16195 type_dependent_expression_p))
16198 if (TREE_CODE (expression) == FUNCTION_DECL
16199 && DECL_LANG_SPECIFIC (expression)
16200 && DECL_TEMPLATE_INFO (expression)
16201 && (any_dependent_template_arguments_p
16202 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
16205 if (TREE_CODE (expression) == TEMPLATE_DECL
16206 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
16209 if (TREE_CODE (expression) == STMT_EXPR)
16210 expression = stmt_expr_value_expr (expression);
16212 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
16217 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
16219 if (type_dependent_expression_p (elt))
16225 if (TREE_TYPE (expression) == unknown_type_node)
16227 if (TREE_CODE (expression) == ADDR_EXPR)
16228 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
16229 if (TREE_CODE (expression) == COMPONENT_REF
16230 || TREE_CODE (expression) == OFFSET_REF)
16232 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
16234 expression = TREE_OPERAND (expression, 1);
16235 if (TREE_CODE (expression) == IDENTIFIER_NODE)
16238 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
16239 if (TREE_CODE (expression) == SCOPE_REF)
16242 if (TREE_CODE (expression) == BASELINK)
16243 expression = BASELINK_FUNCTIONS (expression);
16245 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
16247 if (any_dependent_template_arguments_p
16248 (TREE_OPERAND (expression, 1)))
16250 expression = TREE_OPERAND (expression, 0);
16252 gcc_assert (TREE_CODE (expression) == OVERLOAD
16253 || TREE_CODE (expression) == FUNCTION_DECL);
16257 if (type_dependent_expression_p (OVL_CURRENT (expression)))
16259 expression = OVL_NEXT (expression);
16264 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
16266 return (dependent_type_p (TREE_TYPE (expression)));
16269 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
16270 contains a type-dependent expression. */
16273 any_type_dependent_arguments_p (const_tree args)
16277 tree arg = TREE_VALUE (args);
16279 if (type_dependent_expression_p (arg))
16281 args = TREE_CHAIN (args);
16286 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
16287 expressions) contains any value-dependent expressions. */
16290 any_value_dependent_elements_p (const_tree list)
16292 for (; list; list = TREE_CHAIN (list))
16293 if (value_dependent_expression_p (TREE_VALUE (list)))
16299 /* Returns TRUE if the ARG (a template argument) is dependent. */
16302 dependent_template_arg_p (tree arg)
16304 if (!processing_template_decl)
16307 if (TREE_CODE (arg) == TEMPLATE_DECL
16308 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
16309 return dependent_template_p (arg);
16310 else if (ARGUMENT_PACK_P (arg))
16312 tree args = ARGUMENT_PACK_ARGS (arg);
16313 int i, len = TREE_VEC_LENGTH (args);
16314 for (i = 0; i < len; ++i)
16316 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
16322 else if (TYPE_P (arg))
16323 return dependent_type_p (arg);
16325 return (type_dependent_expression_p (arg)
16326 || value_dependent_expression_p (arg));
16329 /* Returns true if ARGS (a collection of template arguments) contains
16330 any types that require structural equality testing. */
16333 any_template_arguments_need_structural_equality_p (tree args)
16340 if (args == error_mark_node)
16343 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
16345 tree level = TMPL_ARGS_LEVEL (args, i + 1);
16346 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
16348 tree arg = TREE_VEC_ELT (level, j);
16349 tree packed_args = NULL_TREE;
16352 if (ARGUMENT_PACK_P (arg))
16354 /* Look inside the argument pack. */
16355 packed_args = ARGUMENT_PACK_ARGS (arg);
16356 len = TREE_VEC_LENGTH (packed_args);
16359 for (k = 0; k < len; ++k)
16362 arg = TREE_VEC_ELT (packed_args, k);
16364 if (error_operand_p (arg))
16366 else if (TREE_CODE (arg) == TEMPLATE_DECL
16367 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
16369 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
16371 else if (!TYPE_P (arg) && TREE_TYPE (arg)
16372 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
16381 /* Returns true if ARGS (a collection of template arguments) contains
16382 any dependent arguments. */
16385 any_dependent_template_arguments_p (const_tree args)
16392 if (args == error_mark_node)
16395 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
16397 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
16398 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
16399 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
16406 /* Returns TRUE if the template TMPL is dependent. */
16409 dependent_template_p (tree tmpl)
16411 if (TREE_CODE (tmpl) == OVERLOAD)
16415 if (dependent_template_p (OVL_FUNCTION (tmpl)))
16417 tmpl = OVL_CHAIN (tmpl);
16422 /* Template template parameters are dependent. */
16423 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
16424 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
16426 /* So are names that have not been looked up. */
16427 if (TREE_CODE (tmpl) == SCOPE_REF
16428 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
16430 /* So are member templates of dependent classes. */
16431 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
16432 return dependent_type_p (DECL_CONTEXT (tmpl));
16436 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
16439 dependent_template_id_p (tree tmpl, tree args)
16441 return (dependent_template_p (tmpl)
16442 || any_dependent_template_arguments_p (args));
16445 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
16449 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
16453 if (!processing_template_decl)
16456 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
16458 tree decl = TREE_VEC_ELT (declv, i);
16459 tree init = TREE_VEC_ELT (initv, i);
16460 tree cond = TREE_VEC_ELT (condv, i);
16461 tree incr = TREE_VEC_ELT (incrv, i);
16463 if (type_dependent_expression_p (decl))
16466 if (init && type_dependent_expression_p (init))
16469 if (type_dependent_expression_p (cond))
16472 if (COMPARISON_CLASS_P (cond)
16473 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
16474 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
16477 if (TREE_CODE (incr) == MODOP_EXPR)
16479 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
16480 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
16483 else if (type_dependent_expression_p (incr))
16485 else if (TREE_CODE (incr) == MODIFY_EXPR)
16487 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
16489 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
16491 tree t = TREE_OPERAND (incr, 1);
16492 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
16493 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
16502 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
16503 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
16504 no such TYPE can be found. Note that this function peers inside
16505 uninstantiated templates and therefore should be used only in
16506 extremely limited situations. ONLY_CURRENT_P restricts this
16507 peering to the currently open classes hierarchy (which is required
16508 when comparing types). */
16511 resolve_typename_type (tree type, bool only_current_p)
16520 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
16522 scope = TYPE_CONTEXT (type);
16523 name = TYPE_IDENTIFIER (type);
16525 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
16526 it first before we can figure out what NAME refers to. */
16527 if (TREE_CODE (scope) == TYPENAME_TYPE)
16528 scope = resolve_typename_type (scope, only_current_p);
16529 /* If we don't know what SCOPE refers to, then we cannot resolve the
16531 if (TREE_CODE (scope) == TYPENAME_TYPE)
16533 /* If the SCOPE is a template type parameter, we have no way of
16534 resolving the name. */
16535 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
16537 /* If the SCOPE is not the current instantiation, there's no reason
16538 to look inside it. */
16539 if (only_current_p && !currently_open_class (scope))
16541 /* If SCOPE isn't the template itself, it will not have a valid
16542 TYPE_FIELDS list. */
16543 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
16544 /* scope is either the template itself or a compatible instantiation
16545 like X<T>, so look up the name in the original template. */
16546 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
16548 /* scope is a partial instantiation, so we can't do the lookup or we
16549 will lose the template arguments. */
16551 /* Enter the SCOPE so that name lookup will be resolved as if we
16552 were in the class definition. In particular, SCOPE will no
16553 longer be considered a dependent type. */
16554 pushed_scope = push_scope (scope);
16555 /* Look up the declaration. */
16556 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
16558 result = NULL_TREE;
16560 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
16561 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
16564 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
16565 && TREE_CODE (decl) == TYPE_DECL)
16567 result = TREE_TYPE (decl);
16568 if (result == error_mark_node)
16569 result = NULL_TREE;
16571 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
16572 && DECL_CLASS_TEMPLATE_P (decl))
16576 /* Obtain the template and the arguments. */
16577 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
16578 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
16579 /* Instantiate the template. */
16580 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
16581 /*entering_scope=*/0,
16582 tf_error | tf_user);
16583 if (result == error_mark_node)
16584 result = NULL_TREE;
16587 /* Leave the SCOPE. */
16589 pop_scope (pushed_scope);
16591 /* If we failed to resolve it, return the original typename. */
16595 /* If lookup found a typename type, resolve that too. */
16596 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
16598 /* Ill-formed programs can cause infinite recursion here, so we
16599 must catch that. */
16600 TYPENAME_IS_RESOLVING_P (type) = 1;
16601 result = resolve_typename_type (result, only_current_p);
16602 TYPENAME_IS_RESOLVING_P (type) = 0;
16605 /* Qualify the resulting type. */
16606 quals = cp_type_quals (type);
16608 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
16613 /* EXPR is an expression which is not type-dependent. Return a proxy
16614 for EXPR that can be used to compute the types of larger
16615 expressions containing EXPR. */
16618 build_non_dependent_expr (tree expr)
16622 /* Preserve null pointer constants so that the type of things like
16623 "p == 0" where "p" is a pointer can be determined. */
16624 if (null_ptr_cst_p (expr))
16626 /* Preserve OVERLOADs; the functions must be available to resolve
16629 if (TREE_CODE (inner_expr) == STMT_EXPR)
16630 inner_expr = stmt_expr_value_expr (inner_expr);
16631 if (TREE_CODE (inner_expr) == ADDR_EXPR)
16632 inner_expr = TREE_OPERAND (inner_expr, 0);
16633 if (TREE_CODE (inner_expr) == COMPONENT_REF)
16634 inner_expr = TREE_OPERAND (inner_expr, 1);
16635 if (is_overloaded_fn (inner_expr)
16636 || TREE_CODE (inner_expr) == OFFSET_REF)
16638 /* There is no need to return a proxy for a variable. */
16639 if (TREE_CODE (expr) == VAR_DECL)
16641 /* Preserve string constants; conversions from string constants to
16642 "char *" are allowed, even though normally a "const char *"
16643 cannot be used to initialize a "char *". */
16644 if (TREE_CODE (expr) == STRING_CST)
16646 /* Preserve arithmetic constants, as an optimization -- there is no
16647 reason to create a new node. */
16648 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
16650 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
16651 There is at least one place where we want to know that a
16652 particular expression is a throw-expression: when checking a ?:
16653 expression, there are special rules if the second or third
16654 argument is a throw-expression. */
16655 if (TREE_CODE (expr) == THROW_EXPR)
16658 if (TREE_CODE (expr) == COND_EXPR)
16659 return build3 (COND_EXPR,
16661 TREE_OPERAND (expr, 0),
16662 (TREE_OPERAND (expr, 1)
16663 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
16664 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
16665 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
16666 if (TREE_CODE (expr) == COMPOUND_EXPR
16667 && !COMPOUND_EXPR_OVERLOADED (expr))
16668 return build2 (COMPOUND_EXPR,
16670 TREE_OPERAND (expr, 0),
16671 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
16673 /* If the type is unknown, it can't really be non-dependent */
16674 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
16676 /* Otherwise, build a NON_DEPENDENT_EXPR.
16678 REFERENCE_TYPEs are not stripped for expressions in templates
16679 because doing so would play havoc with mangling. Consider, for
16682 template <typename T> void f<T& g>() { g(); }
16684 In the body of "f", the expression for "g" will have
16685 REFERENCE_TYPE, even though the standard says that it should
16686 not. The reason is that we must preserve the syntactic form of
16687 the expression so that mangling (say) "f<g>" inside the body of
16688 "f" works out correctly. Therefore, the REFERENCE_TYPE is
16690 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
16693 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
16694 Return a new TREE_LIST with the various arguments replaced with
16695 equivalent non-dependent expressions. */
16698 build_non_dependent_args (tree args)
16703 new_args = NULL_TREE;
16704 for (a = args; a; a = TREE_CHAIN (a))
16705 new_args = tree_cons (NULL_TREE,
16706 build_non_dependent_expr (TREE_VALUE (a)),
16708 return nreverse (new_args);
16711 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
16712 with a level one deeper than the actual template parms. */
16719 /* ??? Is it worth caching this for multiple autos at the same level? */
16720 au = cxx_make_type (TEMPLATE_TYPE_PARM);
16721 TYPE_NAME (au) = build_decl (TYPE_DECL, get_identifier ("auto"), au);
16722 TYPE_STUB_DECL (au) = TYPE_NAME (au);
16723 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
16724 (0, processing_template_decl + 1, processing_template_decl + 1,
16725 TYPE_NAME (au), NULL_TREE);
16726 TYPE_CANONICAL (au) = canonical_type_parameter (au);
16727 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
16728 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
16733 /* Replace auto in TYPE with std::initializer_list<auto>. */
16736 listify_autos (tree type, tree auto_node)
16738 tree std_init_list = namespace_binding
16739 (get_identifier ("initializer_list"), std_node);
16742 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
16744 error ("deducing auto from brace-enclosed initializer list requires "
16745 "#include <initializer_list>");
16746 return error_mark_node;
16748 argvec = make_tree_vec (1);
16749 TREE_VEC_ELT (argvec, 0) = auto_node;
16750 init_auto = lookup_template_class (std_init_list, argvec, NULL_TREE,
16751 NULL_TREE, 0, tf_warning_or_error);
16753 TREE_VEC_ELT (argvec, 0) = init_auto;
16754 if (processing_template_decl)
16755 argvec = add_to_template_args (current_template_args (), argvec);
16756 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
16759 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
16760 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
16763 do_auto_deduction (tree type, tree init, tree auto_node)
16765 tree parms, args, tparms, targs;
16768 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
16769 with either a new invented type template parameter U or, if the
16770 initializer is a braced-init-list (8.5.4), with
16771 std::initializer_list<U>. */
16772 if (BRACE_ENCLOSED_INITIALIZER_P (init))
16773 type = listify_autos (type, auto_node);
16775 parms = build_tree_list (NULL_TREE, type);
16776 args = build_tree_list (NULL_TREE, init);
16777 tparms = make_tree_vec (1);
16778 targs = make_tree_vec (1);
16779 TREE_VEC_ELT (tparms, 0)
16780 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
16781 val = type_unification_real (tparms, targs, parms, args, 0,
16782 DEDUCE_CALL, LOOKUP_NORMAL);
16785 error ("unable to deduce %qT from %qE", type, init);
16786 return error_mark_node;
16789 if (processing_template_decl)
16790 targs = add_to_template_args (current_template_args (), targs);
16791 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
16794 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
16798 splice_late_return_type (tree type, tree late_return_type)
16802 if (late_return_type == NULL_TREE)
16804 argvec = make_tree_vec (1);
16805 TREE_VEC_ELT (argvec, 0) = late_return_type;
16806 if (processing_template_decl)
16807 argvec = add_to_template_args (current_template_args (), argvec);
16808 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
16811 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
16814 is_auto (const_tree type)
16816 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
16817 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
16823 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
16824 appear as a type-specifier for the declaration in question, we don't
16825 have to look through the whole type. */
16828 type_uses_auto (tree type)
16830 enum tree_code code;
16831 if (is_auto (type))
16834 code = TREE_CODE (type);
16836 if (code == POINTER_TYPE || code == REFERENCE_TYPE
16837 || code == OFFSET_TYPE || code == FUNCTION_TYPE
16838 || code == METHOD_TYPE || code == ARRAY_TYPE)
16839 return type_uses_auto (TREE_TYPE (type));
16841 if (TYPE_PTRMEMFUNC_P (type))
16842 return type_uses_auto (TREE_TYPE (TREE_TYPE
16843 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
16848 #include "gt-cp-pt.h"