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 ("specialization of %qD in different namespace", tmpl);
714 permerror (" 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 ("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 ("specializing %q#T in different namespace", type);
815 permerror (" 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)
1293 DECL_DECLARED_INLINE_P (clone)
1294 = DECL_DECLARED_INLINE_P (fn);
1298 check_specialization_namespace (fn);
1303 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1305 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1306 /* Dup decl failed, but this is a new definition. Set the
1307 line number so any errors match this new
1309 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1315 /* A specialization must be declared in the same namespace as the
1316 template it is specializing. */
1317 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1318 && !check_specialization_namespace (tmpl))
1319 DECL_CONTEXT (spec) = FROB_CONTEXT (decl_namespace_context (tmpl));
1321 if (!optimize_specialization_lookup_p (tmpl))
1322 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1323 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1328 /* Unregister the specialization SPEC as a specialization of TMPL.
1329 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1330 if the SPEC was listed as a specialization of TMPL. */
1333 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1337 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1339 s = &TREE_CHAIN (*s))
1340 if (TREE_VALUE (*s) == spec)
1343 *s = TREE_CHAIN (*s);
1345 TREE_VALUE (*s) = new_spec;
1352 /* Compare an entry in the local specializations hash table P1 (which
1353 is really a pointer to a TREE_LIST) with P2 (which is really a
1357 eq_local_specializations (const void *p1, const void *p2)
1359 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1362 /* Hash P1, an entry in the local specializations table. */
1365 hash_local_specialization (const void* p1)
1367 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1370 /* Like register_specialization, but for local declarations. We are
1371 registering SPEC, an instantiation of TMPL. */
1374 register_local_specialization (tree spec, tree tmpl)
1378 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1379 htab_hash_pointer (tmpl), INSERT);
1380 *slot = build_tree_list (spec, tmpl);
1383 /* TYPE is a class type. Returns true if TYPE is an explicitly
1384 specialized class. */
1387 explicit_class_specialization_p (tree type)
1389 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1391 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1394 /* Print the list of candidate FNS in an error message. */
1397 print_candidates (tree fns)
1401 const char *str = "candidates are:";
1403 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1407 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1408 error ("%s %+#D", str, OVL_CURRENT (f));
1413 /* Returns the template (one of the functions given by TEMPLATE_ID)
1414 which can be specialized to match the indicated DECL with the
1415 explicit template args given in TEMPLATE_ID. The DECL may be
1416 NULL_TREE if none is available. In that case, the functions in
1417 TEMPLATE_ID are non-members.
1419 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1420 specialization of a member template.
1422 The TEMPLATE_COUNT is the number of references to qualifying
1423 template classes that appeared in the name of the function. See
1424 check_explicit_specialization for a more accurate description.
1426 TSK indicates what kind of template declaration (if any) is being
1427 declared. TSK_TEMPLATE indicates that the declaration given by
1428 DECL, though a FUNCTION_DECL, has template parameters, and is
1429 therefore a template function.
1431 The template args (those explicitly specified and those deduced)
1432 are output in a newly created vector *TARGS_OUT.
1434 If it is impossible to determine the result, an error message is
1435 issued. The error_mark_node is returned to indicate failure. */
1438 determine_specialization (tree template_id,
1441 int need_member_template,
1447 tree explicit_targs;
1448 tree candidates = NULL_TREE;
1449 /* A TREE_LIST of templates of which DECL may be a specialization.
1450 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1451 corresponding TREE_PURPOSE is the set of template arguments that,
1452 when used to instantiate the template, would produce a function
1453 with the signature of DECL. */
1454 tree templates = NULL_TREE;
1456 struct cp_binding_level *b;
1458 *targs_out = NULL_TREE;
1460 if (template_id == error_mark_node || decl == error_mark_node)
1461 return error_mark_node;
1463 fns = TREE_OPERAND (template_id, 0);
1464 explicit_targs = TREE_OPERAND (template_id, 1);
1466 if (fns == error_mark_node)
1467 return error_mark_node;
1469 /* Check for baselinks. */
1470 if (BASELINK_P (fns))
1471 fns = BASELINK_FUNCTIONS (fns);
1473 if (!is_overloaded_fn (fns))
1475 error ("%qD is not a function template", fns);
1476 return error_mark_node;
1479 /* Count the number of template headers specified for this
1482 for (b = current_binding_level;
1483 b->kind == sk_template_parms;
1487 for (; fns; fns = OVL_NEXT (fns))
1489 tree fn = OVL_CURRENT (fns);
1491 if (TREE_CODE (fn) == TEMPLATE_DECL)
1493 tree decl_arg_types;
1496 /* In case of explicit specialization, we need to check if
1497 the number of template headers appearing in the specialization
1498 is correct. This is usually done in check_explicit_specialization,
1499 but the check done there cannot be exhaustive when specializing
1500 member functions. Consider the following code:
1502 template <> void A<int>::f(int);
1503 template <> template <> void A<int>::f(int);
1505 Assuming that A<int> is not itself an explicit specialization
1506 already, the first line specializes "f" which is a non-template
1507 member function, whilst the second line specializes "f" which
1508 is a template member function. So both lines are syntactically
1509 correct, and check_explicit_specialization does not reject
1512 Here, we can do better, as we are matching the specialization
1513 against the declarations. We count the number of template
1514 headers, and we check if they match TEMPLATE_COUNT + 1
1515 (TEMPLATE_COUNT is the number of qualifying template classes,
1516 plus there must be another header for the member template
1519 Notice that if header_count is zero, this is not a
1520 specialization but rather a template instantiation, so there
1521 is no check we can perform here. */
1522 if (header_count && header_count != template_count + 1)
1525 /* Check that the number of template arguments at the
1526 innermost level for DECL is the same as for FN. */
1527 if (current_binding_level->kind == sk_template_parms
1528 && !current_binding_level->explicit_spec_p
1529 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1530 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1531 (current_template_parms))))
1534 /* DECL might be a specialization of FN. */
1535 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1536 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1538 /* For a non-static member function, we need to make sure
1539 that the const qualification is the same. Since
1540 get_bindings does not try to merge the "this" parameter,
1541 we must do the comparison explicitly. */
1542 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1543 && !same_type_p (TREE_VALUE (fn_arg_types),
1544 TREE_VALUE (decl_arg_types)))
1547 /* Skip the "this" parameter and, for constructors of
1548 classes with virtual bases, the VTT parameter. A
1549 full specialization of a constructor will have a VTT
1550 parameter, but a template never will. */
1552 = skip_artificial_parms_for (decl, decl_arg_types);
1554 = skip_artificial_parms_for (fn, fn_arg_types);
1556 /* Check that the number of function parameters matches.
1558 template <class T> void f(int i = 0);
1559 template <> void f<int>();
1560 The specialization f<int> is invalid but is not caught
1561 by get_bindings below. */
1562 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1565 /* Function templates cannot be specializations; there are
1566 no partial specializations of functions. Therefore, if
1567 the type of DECL does not match FN, there is no
1569 if (tsk == tsk_template)
1571 if (compparms (fn_arg_types, decl_arg_types))
1572 candidates = tree_cons (NULL_TREE, fn, candidates);
1576 /* See whether this function might be a specialization of this
1578 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1581 /* We cannot deduce template arguments that when used to
1582 specialize TMPL will produce DECL. */
1585 /* Save this template, and the arguments deduced. */
1586 templates = tree_cons (targs, fn, templates);
1588 else if (need_member_template)
1589 /* FN is an ordinary member function, and we need a
1590 specialization of a member template. */
1592 else if (TREE_CODE (fn) != FUNCTION_DECL)
1593 /* We can get IDENTIFIER_NODEs here in certain erroneous
1596 else if (!DECL_FUNCTION_MEMBER_P (fn))
1597 /* This is just an ordinary non-member function. Nothing can
1598 be a specialization of that. */
1600 else if (DECL_ARTIFICIAL (fn))
1601 /* Cannot specialize functions that are created implicitly. */
1605 tree decl_arg_types;
1607 /* This is an ordinary member function. However, since
1608 we're here, we can assume it's enclosing class is a
1609 template class. For example,
1611 template <typename T> struct S { void f(); };
1612 template <> void S<int>::f() {}
1614 Here, S<int>::f is a non-template, but S<int> is a
1615 template class. If FN has the same type as DECL, we
1616 might be in business. */
1618 if (!DECL_TEMPLATE_INFO (fn))
1619 /* Its enclosing class is an explicit specialization
1620 of a template class. This is not a candidate. */
1623 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1624 TREE_TYPE (TREE_TYPE (fn))))
1625 /* The return types differ. */
1628 /* Adjust the type of DECL in case FN is a static member. */
1629 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1630 if (DECL_STATIC_FUNCTION_P (fn)
1631 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1632 decl_arg_types = TREE_CHAIN (decl_arg_types);
1634 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1637 candidates = tree_cons (NULL_TREE, fn, candidates);
1641 if (templates && TREE_CHAIN (templates))
1647 It is possible for a specialization with a given function
1648 signature to be instantiated from more than one function
1649 template. In such cases, explicit specification of the
1650 template arguments must be used to uniquely identify the
1651 function template specialization being specialized.
1653 Note that here, there's no suggestion that we're supposed to
1654 determine which of the candidate templates is most
1655 specialized. However, we, also have:
1659 Partial ordering of overloaded function template
1660 declarations is used in the following contexts to select
1661 the function template to which a function template
1662 specialization refers:
1664 -- when an explicit specialization refers to a function
1667 So, we do use the partial ordering rules, at least for now.
1668 This extension can only serve to make invalid programs valid,
1669 so it's safe. And, there is strong anecdotal evidence that
1670 the committee intended the partial ordering rules to apply;
1671 the EDG front end has that behavior, and John Spicer claims
1672 that the committee simply forgot to delete the wording in
1673 [temp.expl.spec]. */
1674 tree tmpl = most_specialized_instantiation (templates);
1675 if (tmpl != error_mark_node)
1678 TREE_CHAIN (templates) = NULL_TREE;
1682 if (templates == NULL_TREE && candidates == NULL_TREE)
1684 error ("template-id %qD for %q+D does not match any template "
1685 "declaration", template_id, decl);
1686 return error_mark_node;
1688 else if ((templates && TREE_CHAIN (templates))
1689 || (candidates && TREE_CHAIN (candidates))
1690 || (templates && candidates))
1692 error ("ambiguous template specialization %qD for %q+D",
1694 chainon (candidates, templates);
1695 print_candidates (candidates);
1696 return error_mark_node;
1699 /* We have one, and exactly one, match. */
1702 tree fn = TREE_VALUE (candidates);
1703 /* DECL is a re-declaration of a template function. */
1704 if (TREE_CODE (fn) == TEMPLATE_DECL)
1706 /* It was a specialization of an ordinary member function in a
1708 *targs_out = copy_node (DECL_TI_ARGS (fn));
1709 return DECL_TI_TEMPLATE (fn);
1712 /* It was a specialization of a template. */
1713 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1714 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1716 *targs_out = copy_node (targs);
1717 SET_TMPL_ARGS_LEVEL (*targs_out,
1718 TMPL_ARGS_DEPTH (*targs_out),
1719 TREE_PURPOSE (templates));
1722 *targs_out = TREE_PURPOSE (templates);
1723 return TREE_VALUE (templates);
1726 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1727 but with the default argument values filled in from those in the
1731 copy_default_args_to_explicit_spec_1 (tree spec_types,
1734 tree new_spec_types;
1739 if (spec_types == void_list_node)
1740 return void_list_node;
1742 /* Substitute into the rest of the list. */
1744 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1745 TREE_CHAIN (tmpl_types));
1747 /* Add the default argument for this parameter. */
1748 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1749 TREE_VALUE (spec_types),
1753 /* DECL is an explicit specialization. Replicate default arguments
1754 from the template it specializes. (That way, code like:
1756 template <class T> void f(T = 3);
1757 template <> void f(double);
1760 works, as required.) An alternative approach would be to look up
1761 the correct default arguments at the call-site, but this approach
1762 is consistent with how implicit instantiations are handled. */
1765 copy_default_args_to_explicit_spec (tree decl)
1770 tree new_spec_types;
1774 tree object_type = NULL_TREE;
1775 tree in_charge = NULL_TREE;
1776 tree vtt = NULL_TREE;
1778 /* See if there's anything we need to do. */
1779 tmpl = DECL_TI_TEMPLATE (decl);
1780 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1781 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1782 if (TREE_PURPOSE (t))
1787 old_type = TREE_TYPE (decl);
1788 spec_types = TYPE_ARG_TYPES (old_type);
1790 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1792 /* Remove the this pointer, but remember the object's type for
1794 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1795 spec_types = TREE_CHAIN (spec_types);
1796 tmpl_types = TREE_CHAIN (tmpl_types);
1798 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1800 /* DECL may contain more parameters than TMPL due to the extra
1801 in-charge parameter in constructors and destructors. */
1802 in_charge = spec_types;
1803 spec_types = TREE_CHAIN (spec_types);
1805 if (DECL_HAS_VTT_PARM_P (decl))
1808 spec_types = TREE_CHAIN (spec_types);
1812 /* Compute the merged default arguments. */
1814 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1816 /* Compute the new FUNCTION_TYPE. */
1820 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1825 /* Put the in-charge parameter back. */
1826 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1827 TREE_VALUE (in_charge),
1830 new_type = build_method_type_directly (object_type,
1831 TREE_TYPE (old_type),
1835 new_type = build_function_type (TREE_TYPE (old_type),
1837 new_type = cp_build_type_attribute_variant (new_type,
1838 TYPE_ATTRIBUTES (old_type));
1839 new_type = build_exception_variant (new_type,
1840 TYPE_RAISES_EXCEPTIONS (old_type));
1841 TREE_TYPE (decl) = new_type;
1844 /* Check to see if the function just declared, as indicated in
1845 DECLARATOR, and in DECL, is a specialization of a function
1846 template. We may also discover that the declaration is an explicit
1847 instantiation at this point.
1849 Returns DECL, or an equivalent declaration that should be used
1850 instead if all goes well. Issues an error message if something is
1851 amiss. Returns error_mark_node if the error is not easily
1854 FLAGS is a bitmask consisting of the following flags:
1856 2: The function has a definition.
1857 4: The function is a friend.
1859 The TEMPLATE_COUNT is the number of references to qualifying
1860 template classes that appeared in the name of the function. For
1863 template <class T> struct S { void f(); };
1866 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1867 classes are not counted in the TEMPLATE_COUNT, so that in
1869 template <class T> struct S {};
1870 template <> struct S<int> { void f(); }
1871 template <> void S<int>::f();
1873 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1874 invalid; there should be no template <>.)
1876 If the function is a specialization, it is marked as such via
1877 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1878 is set up correctly, and it is added to the list of specializations
1879 for that template. */
1882 check_explicit_specialization (tree declarator,
1887 int have_def = flags & 2;
1888 int is_friend = flags & 4;
1889 int specialization = 0;
1890 int explicit_instantiation = 0;
1891 int member_specialization = 0;
1892 tree ctype = DECL_CLASS_CONTEXT (decl);
1893 tree dname = DECL_NAME (decl);
1898 if (!processing_specialization)
1901 tsk = tsk_excessive_parms;
1904 tsk = current_tmpl_spec_kind (template_count);
1909 if (processing_specialization)
1912 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1914 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1917 /* This could be something like:
1919 template <class T> void f(T);
1920 class S { friend void f<>(int); } */
1924 /* This case handles bogus declarations like template <>
1925 template <class T> void f<int>(); */
1927 error ("template-id %qD in declaration of primary template",
1934 case tsk_invalid_member_spec:
1935 /* The error has already been reported in
1936 check_specialization_scope. */
1937 return error_mark_node;
1939 case tsk_invalid_expl_inst:
1940 error ("template parameter list used in explicit instantiation");
1946 error ("definition provided for explicit instantiation");
1948 explicit_instantiation = 1;
1951 case tsk_excessive_parms:
1952 case tsk_insufficient_parms:
1953 if (tsk == tsk_excessive_parms)
1954 error ("too many template parameter lists in declaration of %qD",
1956 else if (template_header_count)
1957 error("too few template parameter lists in declaration of %qD", decl);
1959 error("explicit specialization of %qD must be introduced by "
1960 "%<template <>%>", decl);
1964 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1966 member_specialization = 1;
1972 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1974 /* This case handles bogus declarations like template <>
1975 template <class T> void f<int>(); */
1977 if (uses_template_parms (declarator))
1978 error ("function template partial specialization %qD "
1979 "is not allowed", declarator);
1981 error ("template-id %qD in declaration of primary template",
1986 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1987 /* This is a specialization of a member template, without
1988 specialization the containing class. Something like:
1990 template <class T> struct S {
1991 template <class U> void f (U);
1993 template <> template <class U> void S<int>::f(U) {}
1995 That's a specialization -- but of the entire template. */
2003 if (specialization || member_specialization)
2005 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2006 for (; t; t = TREE_CHAIN (t))
2007 if (TREE_PURPOSE (t))
2010 ("default argument specified in explicit specialization");
2015 if (specialization || member_specialization || explicit_instantiation)
2017 tree tmpl = NULL_TREE;
2018 tree targs = NULL_TREE;
2020 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2021 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2025 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2030 /* If there is no class context, the explicit instantiation
2031 must be at namespace scope. */
2032 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2034 /* Find the namespace binding, using the declaration
2036 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2038 if (fns == error_mark_node || !is_overloaded_fn (fns))
2040 error ("%qD is not a template function", dname);
2041 fns = error_mark_node;
2045 tree fn = OVL_CURRENT (fns);
2046 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2047 CP_DECL_CONTEXT (fn)))
2048 error ("%qD is not declared in %qD",
2049 decl, current_namespace);
2053 declarator = lookup_template_function (fns, NULL_TREE);
2056 if (declarator == error_mark_node)
2057 return error_mark_node;
2059 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2061 if (!explicit_instantiation)
2062 /* A specialization in class scope. This is invalid,
2063 but the error will already have been flagged by
2064 check_specialization_scope. */
2065 return error_mark_node;
2068 /* It's not valid to write an explicit instantiation in
2071 class C { template void f(); }
2073 This case is caught by the parser. However, on
2076 template class C { void f(); };
2078 (which is invalid) we can get here. The error will be
2085 else if (ctype != NULL_TREE
2086 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2089 /* Find the list of functions in ctype that have the same
2090 name as the declared function. */
2091 tree name = TREE_OPERAND (declarator, 0);
2092 tree fns = NULL_TREE;
2095 if (constructor_name_p (name, ctype))
2097 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2099 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2100 : !CLASSTYPE_DESTRUCTORS (ctype))
2102 /* From [temp.expl.spec]:
2104 If such an explicit specialization for the member
2105 of a class template names an implicitly-declared
2106 special member function (clause _special_), the
2107 program is ill-formed.
2109 Similar language is found in [temp.explicit]. */
2110 error ("specialization of implicitly-declared special member function");
2111 return error_mark_node;
2114 name = is_constructor ? ctor_identifier : dtor_identifier;
2117 if (!DECL_CONV_FN_P (decl))
2119 idx = lookup_fnfields_1 (ctype, name);
2121 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2125 VEC(tree,gc) *methods;
2128 /* For a type-conversion operator, we cannot do a
2129 name-based lookup. We might be looking for `operator
2130 int' which will be a specialization of `operator T'.
2131 So, we find *all* the conversion operators, and then
2132 select from them. */
2135 methods = CLASSTYPE_METHOD_VEC (ctype);
2137 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2138 VEC_iterate (tree, methods, idx, ovl);
2141 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2142 /* There are no more conversion functions. */
2145 /* Glue all these conversion functions together
2146 with those we already have. */
2147 for (; ovl; ovl = OVL_NEXT (ovl))
2148 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2152 if (fns == NULL_TREE)
2154 error ("no member function %qD declared in %qT", name, ctype);
2155 return error_mark_node;
2158 TREE_OPERAND (declarator, 0) = fns;
2161 /* Figure out what exactly is being specialized at this point.
2162 Note that for an explicit instantiation, even one for a
2163 member function, we cannot tell apriori whether the
2164 instantiation is for a member template, or just a member
2165 function of a template class. Even if a member template is
2166 being instantiated, the member template arguments may be
2167 elided if they can be deduced from the rest of the
2169 tmpl = determine_specialization (declarator, decl,
2171 member_specialization,
2175 if (!tmpl || tmpl == error_mark_node)
2176 /* We couldn't figure out what this declaration was
2178 return error_mark_node;
2181 tree gen_tmpl = most_general_template (tmpl);
2183 if (explicit_instantiation)
2185 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2186 is done by do_decl_instantiation later. */
2188 int arg_depth = TMPL_ARGS_DEPTH (targs);
2189 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2191 if (arg_depth > parm_depth)
2193 /* If TMPL is not the most general template (for
2194 example, if TMPL is a friend template that is
2195 injected into namespace scope), then there will
2196 be too many levels of TARGS. Remove some of them
2201 new_targs = make_tree_vec (parm_depth);
2202 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2203 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2204 = TREE_VEC_ELT (targs, i);
2208 return instantiate_template (tmpl, targs, tf_error);
2211 /* If we thought that the DECL was a member function, but it
2212 turns out to be specializing a static member function,
2213 make DECL a static member function as well. */
2214 if (DECL_STATIC_FUNCTION_P (tmpl)
2215 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2216 revert_static_member_fn (decl);
2218 /* If this is a specialization of a member template of a
2219 template class, we want to return the TEMPLATE_DECL, not
2220 the specialization of it. */
2221 if (tsk == tsk_template)
2223 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2224 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2227 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2228 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2229 = DECL_SOURCE_LOCATION (decl);
2230 /* We want to use the argument list specified in the
2231 definition, not in the original declaration. */
2232 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2233 = DECL_ARGUMENTS (decl);
2238 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2239 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2241 /* Inherit default function arguments from the template
2242 DECL is specializing. */
2243 copy_default_args_to_explicit_spec (decl);
2245 /* This specialization has the same protection as the
2246 template it specializes. */
2247 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2248 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2250 /* 7.1.1-1 [dcl.stc]
2252 A storage-class-specifier shall not be specified in an
2253 explicit specialization...
2255 The parser rejects these, so unless action is taken here,
2256 explicit function specializations will always appear with
2259 The action recommended by the C++ CWG in response to C++
2260 defect report 605 is to make the storage class and linkage
2261 of the explicit specialization match the templated function:
2263 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2265 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2267 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2268 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2270 /* This specialization has the same linkage and visibility as
2271 the function template it specializes. */
2272 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2273 if (! TREE_PUBLIC (decl))
2275 DECL_INTERFACE_KNOWN (decl) = 1;
2276 DECL_NOT_REALLY_EXTERN (decl) = 1;
2278 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2279 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2281 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2282 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2286 /* If DECL is a friend declaration, declared using an
2287 unqualified name, the namespace associated with DECL may
2288 have been set incorrectly. For example, in:
2290 template <typename T> void f(T);
2292 struct S { friend void f<int>(int); }
2295 we will have set the DECL_CONTEXT for the friend
2296 declaration to N, rather than to the global namespace. */
2297 if (DECL_NAMESPACE_SCOPE_P (decl))
2298 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2300 if (is_friend && !have_def)
2301 /* This is not really a declaration of a specialization.
2302 It's just the name of an instantiation. But, it's not
2303 a request for an instantiation, either. */
2304 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2305 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2306 /* This is indeed a specialization. In case of constructors
2307 and destructors, we need in-charge and not-in-charge
2308 versions in V3 ABI. */
2309 clone_function_decl (decl, /*update_method_vec_p=*/0);
2311 /* Register this specialization so that we can find it
2313 decl = register_specialization (decl, gen_tmpl, targs, is_friend);
2320 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2321 parameters. These are represented in the same format used for
2322 DECL_TEMPLATE_PARMS. */
2325 comp_template_parms (const_tree parms1, const_tree parms2)
2330 if (parms1 == parms2)
2333 for (p1 = parms1, p2 = parms2;
2334 p1 != NULL_TREE && p2 != NULL_TREE;
2335 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2337 tree t1 = TREE_VALUE (p1);
2338 tree t2 = TREE_VALUE (p2);
2341 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2342 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2344 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2347 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2349 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2350 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2352 /* If either of the template parameters are invalid, assume
2353 they match for the sake of error recovery. */
2354 if (parm1 == error_mark_node || parm2 == error_mark_node)
2357 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2360 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2361 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2362 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2364 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2369 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2370 /* One set of parameters has more parameters lists than the
2377 /* Determine whether PARM is a parameter pack. */
2379 template_parameter_pack_p (const_tree parm)
2381 /* Determine if we have a non-type template parameter pack. */
2382 if (TREE_CODE (parm) == PARM_DECL)
2383 return (DECL_TEMPLATE_PARM_P (parm)
2384 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2386 /* If this is a list of template parameters, we could get a
2387 TYPE_DECL or a TEMPLATE_DECL. */
2388 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2389 parm = TREE_TYPE (parm);
2391 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2392 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2393 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2396 /* Determine whether ARGS describes a variadic template args list,
2397 i.e., one that is terminated by a template argument pack. */
2399 template_args_variadic_p (tree args)
2404 if (args == NULL_TREE)
2407 args = INNERMOST_TEMPLATE_ARGS (args);
2408 nargs = TREE_VEC_LENGTH (args);
2413 last_parm = TREE_VEC_ELT (args, nargs - 1);
2415 return ARGUMENT_PACK_P (last_parm);
2418 /* Generate a new name for the parameter pack name NAME (an
2419 IDENTIFIER_NODE) that incorporates its */
2421 make_ith_pack_parameter_name (tree name, int i)
2423 /* Munge the name to include the parameter index. */
2427 sprintf(numbuf, "%i", i);
2428 newname = (char*)alloca (IDENTIFIER_LENGTH (name) + strlen(numbuf) + 2);
2429 sprintf(newname, "%s#%i", IDENTIFIER_POINTER (name), i);
2430 return get_identifier (newname);
2433 /* Structure used to track the progress of find_parameter_packs_r. */
2434 struct find_parameter_pack_data
2436 /* TREE_LIST that will contain all of the parameter packs found by
2438 tree* parameter_packs;
2440 /* Set of AST nodes that have been visited by the traversal. */
2441 struct pointer_set_t *visited;
2444 /* Identifies all of the argument packs that occur in a template
2445 argument and appends them to the TREE_LIST inside DATA, which is a
2446 find_parameter_pack_data structure. This is a subroutine of
2447 make_pack_expansion and uses_parameter_packs. */
2449 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2452 struct find_parameter_pack_data* ppd =
2453 (struct find_parameter_pack_data*)data;
2454 bool parameter_pack_p = false;
2456 /* Identify whether this is a parameter pack or not. */
2457 switch (TREE_CODE (t))
2459 case TEMPLATE_PARM_INDEX:
2460 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2461 parameter_pack_p = true;
2464 case TEMPLATE_TYPE_PARM:
2465 case TEMPLATE_TEMPLATE_PARM:
2466 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2467 parameter_pack_p = true;
2471 if (FUNCTION_PARAMETER_PACK_P (t))
2473 /* We don't want to walk into the type of a PARM_DECL,
2474 because we don't want to see the type parameter pack. */
2476 parameter_pack_p = true;
2481 /* Not a parameter pack. */
2485 if (parameter_pack_p)
2487 /* Add this parameter pack to the list. */
2488 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2492 cp_walk_tree (&TYPE_CONTEXT (t),
2493 &find_parameter_packs_r, ppd, ppd->visited);
2495 /* This switch statement will return immediately if we don't find a
2497 switch (TREE_CODE (t))
2499 case TEMPLATE_PARM_INDEX:
2502 case BOUND_TEMPLATE_TEMPLATE_PARM:
2503 /* Check the template itself. */
2504 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2505 &find_parameter_packs_r, ppd, ppd->visited);
2506 /* Check the template arguments. */
2507 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2512 case TEMPLATE_TYPE_PARM:
2513 case TEMPLATE_TEMPLATE_PARM:
2520 if (TYPE_PTRMEMFUNC_P (t))
2526 if (TYPE_TEMPLATE_INFO (t))
2527 cp_walk_tree (&TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
2528 &find_parameter_packs_r, ppd, ppd->visited);
2534 cp_walk_tree (&TREE_TYPE (t),
2535 &find_parameter_packs_r, ppd, ppd->visited);
2539 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
2544 case TYPE_PACK_EXPANSION:
2545 case EXPR_PACK_EXPANSION:
2550 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
2555 case IDENTIFIER_NODE:
2556 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
2568 /* Determines if the expression or type T uses any parameter packs. */
2570 uses_parameter_packs (tree t)
2572 tree parameter_packs = NULL_TREE;
2573 struct find_parameter_pack_data ppd;
2574 ppd.parameter_packs = ¶meter_packs;
2575 ppd.visited = pointer_set_create ();
2576 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2577 pointer_set_destroy (ppd.visited);
2578 return parameter_packs != NULL_TREE;
2581 /* Turn ARG, which may be an expression, type, or a TREE_LIST
2582 representation a base-class initializer into a parameter pack
2583 expansion. If all goes well, the resulting node will be an
2584 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
2587 make_pack_expansion (tree arg)
2590 tree parameter_packs = NULL_TREE;
2591 bool for_types = false;
2592 struct find_parameter_pack_data ppd;
2594 if (!arg || arg == error_mark_node)
2597 if (TREE_CODE (arg) == TREE_LIST)
2599 /* The only time we will see a TREE_LIST here is for a base
2600 class initializer. In this case, the TREE_PURPOSE will be a
2601 _TYPE node (representing the base class expansion we're
2602 initializing) and the TREE_VALUE will be a TREE_LIST
2603 containing the initialization arguments.
2605 The resulting expansion looks somewhat different from most
2606 expansions. Rather than returning just one _EXPANSION, we
2607 return a TREE_LIST whose TREE_PURPOSE is a
2608 TYPE_PACK_EXPANSION containing the bases that will be
2609 initialized. The TREE_VALUE will be identical to the
2610 original TREE_VALUE, which is a list of arguments that will
2611 be passed to each base. We do not introduce any new pack
2612 expansion nodes into the TREE_VALUE (although it is possible
2613 that some already exist), because the TREE_PURPOSE and
2614 TREE_VALUE all need to be expanded together with the same
2615 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
2616 resulting TREE_PURPOSE will mention the parameter packs in
2617 both the bases and the arguments to the bases. */
2620 tree parameter_packs = NULL_TREE;
2622 /* Determine which parameter packs will be used by the base
2624 ppd.visited = pointer_set_create ();
2625 ppd.parameter_packs = ¶meter_packs;
2626 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
2629 if (parameter_packs == NULL_TREE)
2631 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
2632 pointer_set_destroy (ppd.visited);
2633 return error_mark_node;
2636 if (TREE_VALUE (arg) != void_type_node)
2638 /* Collect the sets of parameter packs used in each of the
2639 initialization arguments. */
2640 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
2642 /* Determine which parameter packs will be expanded in this
2644 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
2649 pointer_set_destroy (ppd.visited);
2651 /* Create the pack expansion type for the base type. */
2652 purpose = make_node (TYPE_PACK_EXPANSION);
2653 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
2654 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
2656 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2657 they will rarely be compared to anything. */
2658 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
2660 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
2663 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
2666 /* Build the PACK_EXPANSION_* node. */
2667 result = make_node (for_types ? TYPE_PACK_EXPANSION : EXPR_PACK_EXPANSION);
2668 SET_PACK_EXPANSION_PATTERN (result, arg);
2669 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
2671 /* Propagate type and const-expression information. */
2672 TREE_TYPE (result) = TREE_TYPE (arg);
2673 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
2676 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2677 they will rarely be compared to anything. */
2678 SET_TYPE_STRUCTURAL_EQUALITY (result);
2680 /* Determine which parameter packs will be expanded. */
2681 ppd.parameter_packs = ¶meter_packs;
2682 ppd.visited = pointer_set_create ();
2683 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
2684 pointer_set_destroy (ppd.visited);
2686 /* Make sure we found some parameter packs. */
2687 if (parameter_packs == NULL_TREE)
2690 error ("expansion pattern %<%T%> contains no argument packs", arg);
2692 error ("expansion pattern %<%E%> contains no argument packs", arg);
2693 return error_mark_node;
2695 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
2700 /* Checks T for any "bare" parameter packs, which have not yet been
2701 expanded, and issues an error if any are found. This operation can
2702 only be done on full expressions or types (e.g., an expression
2703 statement, "if" condition, etc.), because we could have expressions like:
2705 foo(f(g(h(args)))...)
2707 where "args" is a parameter pack. check_for_bare_parameter_packs
2708 should not be called for the subexpressions args, h(args),
2709 g(h(args)), or f(g(h(args))), because we would produce erroneous
2712 Returns TRUE and emits an error if there were bare parameter packs,
2713 returns FALSE otherwise. */
2715 check_for_bare_parameter_packs (tree t)
2717 tree parameter_packs = NULL_TREE;
2718 struct find_parameter_pack_data ppd;
2720 if (!processing_template_decl || !t || t == error_mark_node)
2723 if (TREE_CODE (t) == TYPE_DECL)
2726 ppd.parameter_packs = ¶meter_packs;
2727 ppd.visited = pointer_set_create ();
2728 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2729 pointer_set_destroy (ppd.visited);
2731 if (parameter_packs)
2733 error ("parameter packs not expanded with %<...%>:");
2734 while (parameter_packs)
2736 tree pack = TREE_VALUE (parameter_packs);
2737 tree name = NULL_TREE;
2739 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
2740 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
2741 name = TYPE_NAME (pack);
2742 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
2743 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
2745 name = DECL_NAME (pack);
2748 inform (" %qD", name);
2750 inform (" <anonymous>");
2752 parameter_packs = TREE_CHAIN (parameter_packs);
2761 /* Expand any parameter packs that occur in the template arguments in
2764 expand_template_argument_pack (tree args)
2766 tree result_args = NULL_TREE;
2767 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
2768 int num_result_args = -1;
2770 /* First, determine if we need to expand anything, and the number of
2771 slots we'll need. */
2772 for (in_arg = 0; in_arg < nargs; ++in_arg)
2774 tree arg = TREE_VEC_ELT (args, in_arg);
2775 if (ARGUMENT_PACK_P (arg))
2777 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
2778 if (num_result_args < 0)
2779 num_result_args = in_arg + num_packed;
2781 num_result_args += num_packed;
2785 if (num_result_args >= 0)
2790 /* If no expansion is necessary, we're done. */
2791 if (num_result_args < 0)
2794 /* Expand arguments. */
2795 result_args = make_tree_vec (num_result_args);
2796 for (in_arg = 0; in_arg < nargs; ++in_arg)
2798 tree arg = TREE_VEC_ELT (args, in_arg);
2799 if (ARGUMENT_PACK_P (arg))
2801 tree packed = ARGUMENT_PACK_ARGS (arg);
2802 int i, num_packed = TREE_VEC_LENGTH (packed);
2803 for (i = 0; i < num_packed; ++i, ++out_arg)
2804 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
2808 TREE_VEC_ELT (result_args, out_arg) = arg;
2816 /* Complain if DECL shadows a template parameter.
2818 [temp.local]: A template-parameter shall not be redeclared within its
2819 scope (including nested scopes). */
2822 check_template_shadow (tree decl)
2826 /* If we're not in a template, we can't possibly shadow a template
2828 if (!current_template_parms)
2831 /* Figure out what we're shadowing. */
2832 if (TREE_CODE (decl) == OVERLOAD)
2833 decl = OVL_CURRENT (decl);
2834 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2836 /* If there's no previous binding for this name, we're not shadowing
2837 anything, let alone a template parameter. */
2841 /* If we're not shadowing a template parameter, we're done. Note
2842 that OLDDECL might be an OVERLOAD (or perhaps even an
2843 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2845 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2848 /* We check for decl != olddecl to avoid bogus errors for using a
2849 name inside a class. We check TPFI to avoid duplicate errors for
2850 inline member templates. */
2852 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2855 error ("declaration of %q+#D", decl);
2856 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 ("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 ("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 ("%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 ("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 ("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 ("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));
5842 /* We don't want to call start_enum for this type, since
5843 the values for the enumeration constants may involve
5844 template parameters. And, no one should be interested
5845 in the enumeration constants for such a type. */
5846 t = make_node (ENUMERAL_TYPE);
5850 t = make_class_type (TREE_CODE (template_type));
5851 CLASSTYPE_DECLARED_CLASS (t)
5852 = CLASSTYPE_DECLARED_CLASS (template_type);
5853 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
5854 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
5856 /* A local class. Make sure the decl gets registered properly. */
5857 if (context == current_function_decl)
5858 pushtag (DECL_NAME (templ), t, /*tag_scope=*/ts_current);
5860 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
5861 /* This instantiation is another name for the primary
5862 template type. Set the TYPE_CANONICAL field
5864 TYPE_CANONICAL (t) = template_type;
5865 else if (any_template_arguments_need_structural_equality_p (arglist))
5866 /* Some of the template arguments require structural
5867 equality testing, so this template class requires
5868 structural equality testing. */
5869 SET_TYPE_STRUCTURAL_EQUALITY (t);
5872 /* If we called start_enum or pushtag above, this information
5873 will already be set up. */
5876 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
5878 type_decl = create_implicit_typedef (DECL_NAME (templ), t);
5879 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
5880 TYPE_STUB_DECL (t) = type_decl;
5881 DECL_SOURCE_LOCATION (type_decl)
5882 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
5885 type_decl = TYPE_NAME (t);
5887 TREE_PRIVATE (type_decl)
5888 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
5889 TREE_PROTECTED (type_decl)
5890 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
5891 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
5893 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
5894 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
5897 /* Set up the template information. We have to figure out which
5898 template is the immediate parent if this is a full
5900 if (parm_depth == 1 || is_partial_instantiation
5901 || !PRIMARY_TEMPLATE_P (templ))
5902 /* This case is easy; there are no member templates involved. */
5906 /* This is a full instantiation of a member template. Look
5907 for a partial instantiation of which this is an instance. */
5909 for (found = DECL_TEMPLATE_INSTANTIATIONS (templ);
5910 found; found = TREE_CHAIN (found))
5913 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
5915 /* We only want partial instantiations, here, not
5916 specializations or full instantiations. */
5917 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
5918 || !uses_template_parms (TREE_VALUE (found)))
5921 /* Temporarily reduce by one the number of levels in the
5922 ARGLIST and in FOUND so as to avoid comparing the
5923 last set of arguments. */
5924 TREE_VEC_LENGTH (arglist)--;
5925 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
5927 /* See if the arguments match. If they do, then TMPL is
5928 the partial instantiation we want. */
5929 success = comp_template_args (TREE_PURPOSE (found), arglist);
5931 /* Restore the argument vectors to their full size. */
5932 TREE_VEC_LENGTH (arglist)++;
5933 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
5944 /* There was no partial instantiation. This happens
5945 where C<T> is a member template of A<T> and it's used
5948 template <typename T> struct B { A<T>::C<int> m; };
5951 Create the partial instantiation.
5953 TREE_VEC_LENGTH (arglist)--;
5954 found = tsubst (templ, arglist, complain, NULL_TREE);
5955 TREE_VEC_LENGTH (arglist)++;
5959 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
5960 DECL_TEMPLATE_INSTANTIATIONS (templ)
5961 = tree_cons (arglist, t,
5962 DECL_TEMPLATE_INSTANTIATIONS (templ));
5964 if (TREE_CODE (t) == ENUMERAL_TYPE
5965 && !is_partial_instantiation)
5966 /* Now that the type has been registered on the instantiations
5967 list, we set up the enumerators. Because the enumeration
5968 constants may involve the enumeration type itself, we make
5969 sure to register the type first, and then create the
5970 constants. That way, doing tsubst_expr for the enumeration
5971 constants won't result in recursive calls here; we'll find
5972 the instantiation and exit above. */
5973 tsubst_enum (template_type, t, arglist);
5975 if (is_partial_instantiation)
5976 /* If the type makes use of template parameters, the
5977 code that generates debugging information will crash. */
5978 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
5980 /* Possibly limit visibility based on template args. */
5981 TREE_PUBLIC (type_decl) = 1;
5982 determine_visibility (type_decl);
5984 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
5986 timevar_pop (TV_NAME_LOOKUP);
5993 /* True when we should also visit template parameters that occur in
5994 non-deduced contexts. */
5995 bool include_nondeduced_p;
5996 struct pointer_set_t *visited;
5999 /* Called from for_each_template_parm via walk_tree. */
6002 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
6005 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
6006 tree_fn_t fn = pfd->fn;
6007 void *data = pfd->data;
6010 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
6011 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
6012 pfd->include_nondeduced_p))
6013 return error_mark_node;
6015 switch (TREE_CODE (t))
6018 if (TYPE_PTRMEMFUNC_P (t))
6024 if (!TYPE_TEMPLATE_INFO (t))
6026 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
6027 fn, data, pfd->visited,
6028 pfd->include_nondeduced_p))
6029 return error_mark_node;
6033 if (for_each_template_parm (TYPE_MIN_VALUE (t),
6034 fn, data, pfd->visited,
6035 pfd->include_nondeduced_p)
6036 || for_each_template_parm (TYPE_MAX_VALUE (t),
6037 fn, data, pfd->visited,
6038 pfd->include_nondeduced_p))
6039 return error_mark_node;
6043 /* Since we're not going to walk subtrees, we have to do this
6045 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
6046 pfd->visited, pfd->include_nondeduced_p))
6047 return error_mark_node;
6051 /* Check the return type. */
6052 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6053 pfd->include_nondeduced_p))
6054 return error_mark_node;
6056 /* Check the parameter types. Since default arguments are not
6057 instantiated until they are needed, the TYPE_ARG_TYPES may
6058 contain expressions that involve template parameters. But,
6059 no-one should be looking at them yet. And, once they're
6060 instantiated, they don't contain template parameters, so
6061 there's no point in looking at them then, either. */
6065 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
6066 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
6067 pfd->visited, pfd->include_nondeduced_p))
6068 return error_mark_node;
6070 /* Since we've already handled the TYPE_ARG_TYPES, we don't
6071 want walk_tree walking into them itself. */
6077 if (pfd->include_nondeduced_p
6078 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
6080 pfd->include_nondeduced_p))
6081 return error_mark_node;
6086 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
6087 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
6088 pfd->visited, pfd->include_nondeduced_p))
6089 return error_mark_node;
6094 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
6095 && for_each_template_parm (DECL_INITIAL (t), fn, data,
6096 pfd->visited, pfd->include_nondeduced_p))
6097 return error_mark_node;
6098 if (DECL_CONTEXT (t)
6099 && pfd->include_nondeduced_p
6100 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
6101 pfd->visited, pfd->include_nondeduced_p))
6102 return error_mark_node;
6105 case BOUND_TEMPLATE_TEMPLATE_PARM:
6106 /* Record template parameters such as `T' inside `TT<T>'. */
6107 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
6108 pfd->include_nondeduced_p))
6109 return error_mark_node;
6112 case TEMPLATE_TEMPLATE_PARM:
6113 case TEMPLATE_TYPE_PARM:
6114 case TEMPLATE_PARM_INDEX:
6115 if (fn && (*fn)(t, data))
6116 return error_mark_node;
6118 return error_mark_node;
6122 /* A template template parameter is encountered. */
6123 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
6124 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6125 pfd->include_nondeduced_p))
6126 return error_mark_node;
6128 /* Already substituted template template parameter */
6134 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
6136 pfd->include_nondeduced_p))
6137 return error_mark_node;
6141 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
6142 && pfd->include_nondeduced_p
6143 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
6144 (TREE_TYPE (t)), fn, data,
6145 pfd->visited, pfd->include_nondeduced_p))
6146 return error_mark_node;
6151 /* If there's no type, then this thing must be some expression
6152 involving template parameters. */
6153 if (!fn && !TREE_TYPE (t))
6154 return error_mark_node;
6159 case REINTERPRET_CAST_EXPR:
6160 case CONST_CAST_EXPR:
6161 case STATIC_CAST_EXPR:
6162 case DYNAMIC_CAST_EXPR:
6166 case PSEUDO_DTOR_EXPR:
6168 return error_mark_node;
6175 /* We didn't find any template parameters we liked. */
6179 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
6180 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
6181 call FN with the parameter and the DATA.
6182 If FN returns nonzero, the iteration is terminated, and
6183 for_each_template_parm returns 1. Otherwise, the iteration
6184 continues. If FN never returns a nonzero value, the value
6185 returned by for_each_template_parm is 0. If FN is NULL, it is
6186 considered to be the function which always returns 1.
6188 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
6189 parameters that occur in non-deduced contexts. When false, only
6190 visits those template parameters that can be deduced. */
6193 for_each_template_parm (tree t, tree_fn_t fn, void* data,
6194 struct pointer_set_t *visited,
6195 bool include_nondeduced_p)
6197 struct pair_fn_data pfd;
6203 pfd.include_nondeduced_p = include_nondeduced_p;
6205 /* Walk the tree. (Conceptually, we would like to walk without
6206 duplicates, but for_each_template_parm_r recursively calls
6207 for_each_template_parm, so we would need to reorganize a fair
6208 bit to use walk_tree_without_duplicates, so we keep our own
6211 pfd.visited = visited;
6213 pfd.visited = pointer_set_create ();
6214 result = cp_walk_tree (&t,
6215 for_each_template_parm_r,
6217 pfd.visited) != NULL_TREE;
6222 pointer_set_destroy (pfd.visited);
6229 /* Returns true if T depends on any template parameter. */
6232 uses_template_parms (tree t)
6235 int saved_processing_template_decl;
6237 saved_processing_template_decl = processing_template_decl;
6238 if (!saved_processing_template_decl)
6239 processing_template_decl = 1;
6241 dependent_p = dependent_type_p (t);
6242 else if (TREE_CODE (t) == TREE_VEC)
6243 dependent_p = any_dependent_template_arguments_p (t);
6244 else if (TREE_CODE (t) == TREE_LIST)
6245 dependent_p = (uses_template_parms (TREE_VALUE (t))
6246 || uses_template_parms (TREE_CHAIN (t)));
6247 else if (TREE_CODE (t) == TYPE_DECL)
6248 dependent_p = dependent_type_p (TREE_TYPE (t));
6251 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
6252 || TREE_CODE (t) == OVERLOAD
6253 || TREE_CODE (t) == BASELINK
6254 || TREE_CODE (t) == IDENTIFIER_NODE
6255 || TREE_CODE (t) == TRAIT_EXPR
6256 || CONSTANT_CLASS_P (t))
6257 dependent_p = (type_dependent_expression_p (t)
6258 || value_dependent_expression_p (t));
6261 gcc_assert (t == error_mark_node);
6262 dependent_p = false;
6265 processing_template_decl = saved_processing_template_decl;
6270 /* Returns true if T depends on any template parameter with level LEVEL. */
6273 uses_template_parms_level (tree t, int level)
6275 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
6276 /*include_nondeduced_p=*/true);
6279 static int tinst_depth;
6280 extern int max_tinst_depth;
6281 #ifdef GATHER_STATISTICS
6284 static int tinst_level_tick;
6285 static int last_template_error_tick;
6287 /* We're starting to instantiate D; record the template instantiation context
6288 for diagnostics and to restore it later. */
6291 push_tinst_level (tree d)
6293 struct tinst_level *new_level;
6295 if (tinst_depth >= max_tinst_depth)
6297 /* If the instantiation in question still has unbound template parms,
6298 we don't really care if we can't instantiate it, so just return.
6299 This happens with base instantiation for implicit `typename'. */
6300 if (uses_template_parms (d))
6303 last_template_error_tick = tinst_level_tick;
6304 error ("template instantiation depth exceeds maximum of %d (use "
6305 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
6306 max_tinst_depth, d);
6308 print_instantiation_context ();
6313 new_level = GGC_NEW (struct tinst_level);
6314 new_level->decl = d;
6315 new_level->locus = input_location;
6316 new_level->in_system_header_p = in_system_header;
6317 new_level->next = current_tinst_level;
6318 current_tinst_level = new_level;
6321 #ifdef GATHER_STATISTICS
6322 if (tinst_depth > depth_reached)
6323 depth_reached = tinst_depth;
6330 /* We're done instantiating this template; return to the instantiation
6334 pop_tinst_level (void)
6336 /* Restore the filename and line number stashed away when we started
6337 this instantiation. */
6338 input_location = current_tinst_level->locus;
6339 current_tinst_level = current_tinst_level->next;
6344 /* We're instantiating a deferred template; restore the template
6345 instantiation context in which the instantiation was requested, which
6346 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
6349 reopen_tinst_level (struct tinst_level *level)
6351 struct tinst_level *t;
6354 for (t = level; t; t = t->next)
6357 current_tinst_level = level;
6362 /* Returns the TINST_LEVEL which gives the original instantiation
6365 struct tinst_level *
6366 outermost_tinst_level (void)
6368 struct tinst_level *level = current_tinst_level;
6371 level = level->next;
6375 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
6376 vector of template arguments, as for tsubst.
6378 Returns an appropriate tsubst'd friend declaration. */
6381 tsubst_friend_function (tree decl, tree args)
6385 if (TREE_CODE (decl) == FUNCTION_DECL
6386 && DECL_TEMPLATE_INSTANTIATION (decl)
6387 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
6388 /* This was a friend declared with an explicit template
6389 argument list, e.g.:
6393 to indicate that f was a template instantiation, not a new
6394 function declaration. Now, we have to figure out what
6395 instantiation of what template. */
6397 tree template_id, arglist, fns;
6400 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
6402 /* Friend functions are looked up in the containing namespace scope.
6403 We must enter that scope, to avoid finding member functions of the
6404 current class with same name. */
6405 push_nested_namespace (ns);
6406 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
6407 tf_warning_or_error, NULL_TREE,
6408 /*integral_constant_expression_p=*/false);
6409 pop_nested_namespace (ns);
6410 arglist = tsubst (DECL_TI_ARGS (decl), args,
6411 tf_warning_or_error, NULL_TREE);
6412 template_id = lookup_template_function (fns, arglist);
6414 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6415 tmpl = determine_specialization (template_id, new_friend,
6417 /*need_member_template=*/0,
6418 TREE_VEC_LENGTH (args),
6420 return instantiate_template (tmpl, new_args, tf_error);
6423 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6425 /* The NEW_FRIEND will look like an instantiation, to the
6426 compiler, but is not an instantiation from the point of view of
6427 the language. For example, we might have had:
6429 template <class T> struct S {
6430 template <class U> friend void f(T, U);
6433 Then, in S<int>, template <class U> void f(int, U) is not an
6434 instantiation of anything. */
6435 if (new_friend == error_mark_node)
6436 return error_mark_node;
6438 DECL_USE_TEMPLATE (new_friend) = 0;
6439 if (TREE_CODE (decl) == TEMPLATE_DECL)
6441 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
6442 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
6443 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
6446 /* The mangled name for the NEW_FRIEND is incorrect. The function
6447 is not a template instantiation and should not be mangled like
6448 one. Therefore, we forget the mangling here; we'll recompute it
6449 later if we need it. */
6450 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
6452 SET_DECL_RTL (new_friend, NULL_RTX);
6453 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
6456 if (DECL_NAMESPACE_SCOPE_P (new_friend))
6459 tree new_friend_template_info;
6460 tree new_friend_result_template_info;
6462 int new_friend_is_defn;
6464 /* We must save some information from NEW_FRIEND before calling
6465 duplicate decls since that function will free NEW_FRIEND if
6467 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
6468 new_friend_is_defn =
6469 (DECL_INITIAL (DECL_TEMPLATE_RESULT
6470 (template_for_substitution (new_friend)))
6472 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
6474 /* This declaration is a `primary' template. */
6475 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
6477 new_friend_result_template_info
6478 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
6481 new_friend_result_template_info = NULL_TREE;
6483 /* Make the init_value nonzero so pushdecl knows this is a defn. */
6484 if (new_friend_is_defn)
6485 DECL_INITIAL (new_friend) = error_mark_node;
6487 /* Inside pushdecl_namespace_level, we will push into the
6488 current namespace. However, the friend function should go
6489 into the namespace of the template. */
6490 ns = decl_namespace_context (new_friend);
6491 push_nested_namespace (ns);
6492 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
6493 pop_nested_namespace (ns);
6495 if (old_decl == error_mark_node)
6496 return error_mark_node;
6498 if (old_decl != new_friend)
6500 /* This new friend declaration matched an existing
6501 declaration. For example, given:
6503 template <class T> void f(T);
6504 template <class U> class C {
6505 template <class T> friend void f(T) {}
6508 the friend declaration actually provides the definition
6509 of `f', once C has been instantiated for some type. So,
6510 old_decl will be the out-of-class template declaration,
6511 while new_friend is the in-class definition.
6513 But, if `f' was called before this point, the
6514 instantiation of `f' will have DECL_TI_ARGS corresponding
6515 to `T' but not to `U', references to which might appear
6516 in the definition of `f'. Previously, the most general
6517 template for an instantiation of `f' was the out-of-class
6518 version; now it is the in-class version. Therefore, we
6519 run through all specialization of `f', adding to their
6520 DECL_TI_ARGS appropriately. In particular, they need a
6521 new set of outer arguments, corresponding to the
6522 arguments for this class instantiation.
6524 The same situation can arise with something like this:
6527 template <class T> class C {
6531 when `C<int>' is instantiated. Now, `f(int)' is defined
6534 if (!new_friend_is_defn)
6535 /* On the other hand, if the in-class declaration does
6536 *not* provide a definition, then we don't want to alter
6537 existing definitions. We can just leave everything
6542 /* Overwrite whatever template info was there before, if
6543 any, with the new template information pertaining to
6545 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
6547 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
6548 reregister_specialization (new_friend,
6549 most_general_template (old_decl),
6554 tree new_friend_args;
6556 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
6557 = new_friend_result_template_info;
6559 new_friend_args = TI_ARGS (new_friend_template_info);
6560 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
6564 tree spec = TREE_VALUE (t);
6567 = add_outermost_template_args (new_friend_args,
6568 DECL_TI_ARGS (spec));
6571 /* Now, since specializations are always supposed to
6572 hang off of the most general template, we must move
6574 t = most_general_template (old_decl);
6577 DECL_TEMPLATE_SPECIALIZATIONS (t)
6578 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
6579 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
6580 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
6585 /* The information from NEW_FRIEND has been merged into OLD_DECL
6586 by duplicate_decls. */
6587 new_friend = old_decl;
6592 tree context = DECL_CONTEXT (new_friend);
6596 template <class T> class C {
6597 template <class U> friend void C1<U>::f (); // case 1
6598 friend void C2<T>::f (); // case 2
6600 we only need to make sure CONTEXT is a complete type for
6601 case 2. To distinguish between the two cases, we note that
6602 CONTEXT of case 1 remains dependent type after tsubst while
6603 this isn't true for case 2. */
6604 ++processing_template_decl;
6605 dependent_p = dependent_type_p (context);
6606 --processing_template_decl;
6609 && !complete_type_or_else (context, NULL_TREE))
6610 return error_mark_node;
6612 if (COMPLETE_TYPE_P (context))
6614 /* Check to see that the declaration is really present, and,
6615 possibly obtain an improved declaration. */
6616 tree fn = check_classfn (context,
6617 new_friend, NULL_TREE);
6627 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
6628 template arguments, as for tsubst.
6630 Returns an appropriate tsubst'd friend type or error_mark_node on
6634 tsubst_friend_class (tree friend_tmpl, tree args)
6640 context = DECL_CONTEXT (friend_tmpl);
6644 if (TREE_CODE (context) == NAMESPACE_DECL)
6645 push_nested_namespace (context);
6647 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
6650 /* Look for a class template declaration. We look for hidden names
6651 because two friend declarations of the same template are the
6652 same. For example, in:
6655 template <typename> friend class F;
6657 template <typename> struct B {
6658 template <typename> friend class F;
6661 both F templates are the same. */
6662 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
6663 /*block_p=*/true, 0,
6664 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
6666 /* But, if we don't find one, it might be because we're in a
6667 situation like this:
6675 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
6676 for `S<int>', not the TEMPLATE_DECL. */
6677 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
6679 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
6680 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
6683 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
6685 /* The friend template has already been declared. Just
6686 check to see that the declarations match, and install any new
6687 default parameters. We must tsubst the default parameters,
6688 of course. We only need the innermost template parameters
6689 because that is all that redeclare_class_template will look
6691 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
6692 > TMPL_ARGS_DEPTH (args))
6695 location_t saved_input_location;
6696 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
6697 args, tf_warning_or_error);
6699 saved_input_location = input_location;
6700 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
6701 redeclare_class_template (TREE_TYPE (tmpl), parms);
6702 input_location = saved_input_location;
6706 friend_type = TREE_TYPE (tmpl);
6710 /* The friend template has not already been declared. In this
6711 case, the instantiation of the template class will cause the
6712 injection of this template into the global scope. */
6713 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
6714 if (tmpl == error_mark_node)
6715 return error_mark_node;
6717 /* The new TMPL is not an instantiation of anything, so we
6718 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
6719 the new type because that is supposed to be the corresponding
6720 template decl, i.e., TMPL. */
6721 DECL_USE_TEMPLATE (tmpl) = 0;
6722 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
6723 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
6724 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
6725 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
6727 /* Inject this template into the global scope. */
6728 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
6733 if (TREE_CODE (context) == NAMESPACE_DECL)
6734 pop_nested_namespace (context);
6736 pop_nested_class ();
6742 /* Returns zero if TYPE cannot be completed later due to circularity.
6743 Otherwise returns one. */
6746 can_complete_type_without_circularity (tree type)
6748 if (type == NULL_TREE || type == error_mark_node)
6750 else if (COMPLETE_TYPE_P (type))
6752 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
6753 return can_complete_type_without_circularity (TREE_TYPE (type));
6754 else if (CLASS_TYPE_P (type)
6755 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
6761 /* Apply any attributes which had to be deferred until instantiation
6762 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
6763 ARGS, COMPLAIN, IN_DECL are as tsubst. */
6766 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
6767 tree args, tsubst_flags_t complain, tree in_decl)
6769 tree last_dep = NULL_TREE;
6773 for (t = attributes; t; t = TREE_CHAIN (t))
6774 if (ATTR_IS_DEPENDENT (t))
6777 attributes = copy_list (attributes);
6781 if (DECL_P (*decl_p))
6783 if (TREE_TYPE (*decl_p) == error_mark_node)
6785 p = &DECL_ATTRIBUTES (*decl_p);
6788 p = &TYPE_ATTRIBUTES (*decl_p);
6792 tree late_attrs = NULL_TREE;
6793 tree *q = &late_attrs;
6795 for (*p = attributes; *p; )
6798 if (ATTR_IS_DEPENDENT (t))
6800 *p = TREE_CHAIN (t);
6801 TREE_CHAIN (t) = NULL_TREE;
6802 /* If the first attribute argument is an identifier, don't
6803 pass it through tsubst. Attributes like mode, format,
6804 cleanup and several target specific attributes expect it
6807 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
6808 && TREE_VALUE (TREE_VALUE (t))
6809 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
6810 == IDENTIFIER_NODE))
6813 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
6815 /*integral_constant_expression_p=*/false);
6816 if (chain != TREE_CHAIN (TREE_VALUE (t)))
6818 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
6823 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
6824 /*integral_constant_expression_p=*/false);
6826 q = &TREE_CHAIN (t);
6829 p = &TREE_CHAIN (t);
6832 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
6837 instantiate_class_template (tree type)
6839 tree templ, args, pattern, t, member;
6844 if (type == error_mark_node)
6845 return error_mark_node;
6847 if (TYPE_BEING_DEFINED (type)
6848 || COMPLETE_TYPE_P (type)
6849 || dependent_type_p (type))
6852 /* Figure out which template is being instantiated. */
6853 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
6854 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
6856 /* Determine what specialization of the original template to
6858 t = most_specialized_class (type, templ);
6859 if (t == error_mark_node)
6861 TYPE_BEING_DEFINED (type) = 1;
6862 return error_mark_node;
6866 /* This TYPE is actually an instantiation of a partial
6867 specialization. We replace the innermost set of ARGS with
6868 the arguments appropriate for substitution. For example,
6871 template <class T> struct S {};
6872 template <class T> struct S<T*> {};
6874 and supposing that we are instantiating S<int*>, ARGS will
6875 presently be {int*} -- but we need {int}. */
6876 pattern = TREE_TYPE (t);
6877 args = TREE_PURPOSE (t);
6881 pattern = TREE_TYPE (templ);
6882 args = CLASSTYPE_TI_ARGS (type);
6885 /* If the template we're instantiating is incomplete, then clearly
6886 there's nothing we can do. */
6887 if (!COMPLETE_TYPE_P (pattern))
6890 /* If we've recursively instantiated too many templates, stop. */
6891 if (! push_tinst_level (type))
6894 /* Now we're really doing the instantiation. Mark the type as in
6895 the process of being defined. */
6896 TYPE_BEING_DEFINED (type) = 1;
6898 /* We may be in the middle of deferred access check. Disable
6900 push_deferring_access_checks (dk_no_deferred);
6902 push_to_top_level ();
6904 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
6906 /* Set the input location to the template definition. This is needed
6907 if tsubsting causes an error. */
6908 typedecl = TYPE_MAIN_DECL (type);
6909 input_location = DECL_SOURCE_LOCATION (typedecl);
6911 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
6912 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
6913 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
6914 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
6915 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
6916 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
6917 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
6918 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
6919 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
6920 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
6921 TYPE_PACKED (type) = TYPE_PACKED (pattern);
6922 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
6923 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
6924 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
6925 if (ANON_AGGR_TYPE_P (pattern))
6926 SET_ANON_AGGR_TYPE_P (type);
6927 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
6929 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
6930 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
6933 pbinfo = TYPE_BINFO (pattern);
6935 /* We should never instantiate a nested class before its enclosing
6936 class; we need to look up the nested class by name before we can
6937 instantiate it, and that lookup should instantiate the enclosing
6939 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
6940 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
6941 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
6943 base_list = NULL_TREE;
6944 if (BINFO_N_BASE_BINFOS (pbinfo))
6947 tree context = TYPE_CONTEXT (type);
6951 /* We must enter the scope containing the type, as that is where
6952 the accessibility of types named in dependent bases are
6954 pushed_scope = push_scope (context ? context : global_namespace);
6956 /* Substitute into each of the bases to determine the actual
6958 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
6961 tree access = BINFO_BASE_ACCESS (pbinfo, i);
6962 tree expanded_bases = NULL_TREE;
6965 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
6968 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
6969 args, tf_error, NULL_TREE);
6970 if (expanded_bases == error_mark_node)
6973 len = TREE_VEC_LENGTH (expanded_bases);
6976 for (idx = 0; idx < len; idx++)
6979 /* Extract the already-expanded base class. */
6980 base = TREE_VEC_ELT (expanded_bases, idx);
6982 /* Substitute to figure out the base class. */
6983 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
6986 if (base == error_mark_node)
6989 base_list = tree_cons (access, base, base_list);
6990 if (BINFO_VIRTUAL_P (pbase_binfo))
6991 TREE_TYPE (base_list) = integer_type_node;
6995 /* The list is now in reverse order; correct that. */
6996 base_list = nreverse (base_list);
6999 pop_scope (pushed_scope);
7001 /* Now call xref_basetypes to set up all the base-class
7003 xref_basetypes (type, base_list);
7005 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
7006 (int) ATTR_FLAG_TYPE_IN_PLACE,
7007 args, tf_error, NULL_TREE);
7009 /* Now that our base classes are set up, enter the scope of the
7010 class, so that name lookups into base classes, etc. will work
7011 correctly. This is precisely analogous to what we do in
7012 begin_class_definition when defining an ordinary non-template
7013 class, except we also need to push the enclosing classes. */
7014 push_nested_class (type);
7016 /* Now members are processed in the order of declaration. */
7017 for (member = CLASSTYPE_DECL_LIST (pattern);
7018 member; member = TREE_CHAIN (member))
7020 tree t = TREE_VALUE (member);
7022 if (TREE_PURPOSE (member))
7026 /* Build new CLASSTYPE_NESTED_UTDS. */
7029 bool class_template_p;
7031 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
7032 && TYPE_LANG_SPECIFIC (t)
7033 && CLASSTYPE_IS_TEMPLATE (t));
7034 /* If the member is a class template, then -- even after
7035 substitution -- there may be dependent types in the
7036 template argument list for the class. We increment
7037 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
7038 that function will assume that no types are dependent
7039 when outside of a template. */
7040 if (class_template_p)
7041 ++processing_template_decl;
7042 newtag = tsubst (t, args, tf_error, NULL_TREE);
7043 if (class_template_p)
7044 --processing_template_decl;
7045 if (newtag == error_mark_node)
7048 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
7050 tree name = TYPE_IDENTIFIER (t);
7052 if (class_template_p)
7053 /* Unfortunately, lookup_template_class sets
7054 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
7055 instantiation (i.e., for the type of a member
7056 template class nested within a template class.)
7057 This behavior is required for
7058 maybe_process_partial_specialization to work
7059 correctly, but is not accurate in this case;
7060 the TAG is not an instantiation of anything.
7061 (The corresponding TEMPLATE_DECL is an
7062 instantiation, but the TYPE is not.) */
7063 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
7065 /* Now, we call pushtag to put this NEWTAG into the scope of
7066 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
7067 pushtag calling push_template_decl. We don't have to do
7068 this for enums because it will already have been done in
7071 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
7072 pushtag (name, newtag, /*tag_scope=*/ts_current);
7075 else if (TREE_CODE (t) == FUNCTION_DECL
7076 || DECL_FUNCTION_TEMPLATE_P (t))
7078 /* Build new TYPE_METHODS. */
7081 if (TREE_CODE (t) == TEMPLATE_DECL)
7082 ++processing_template_decl;
7083 r = tsubst (t, args, tf_error, NULL_TREE);
7084 if (TREE_CODE (t) == TEMPLATE_DECL)
7085 --processing_template_decl;
7086 set_current_access_from_decl (r);
7087 finish_member_declaration (r);
7091 /* Build new TYPE_FIELDS. */
7092 if (TREE_CODE (t) == STATIC_ASSERT)
7095 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
7096 tf_warning_or_error, NULL_TREE,
7097 /*integral_constant_expression_p=*/true);
7098 finish_static_assert (condition,
7099 STATIC_ASSERT_MESSAGE (t),
7100 STATIC_ASSERT_SOURCE_LOCATION (t),
7103 else if (TREE_CODE (t) != CONST_DECL)
7107 /* The file and line for this declaration, to
7108 assist in error message reporting. Since we
7109 called push_tinst_level above, we don't need to
7111 input_location = DECL_SOURCE_LOCATION (t);
7113 if (TREE_CODE (t) == TEMPLATE_DECL)
7114 ++processing_template_decl;
7115 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
7116 if (TREE_CODE (t) == TEMPLATE_DECL)
7117 --processing_template_decl;
7118 if (TREE_CODE (r) == VAR_DECL)
7122 [t]he initialization (and any associated
7123 side-effects) of a static data member does
7124 not occur unless the static data member is
7125 itself used in a way that requires the
7126 definition of the static data member to
7129 Therefore, we do not substitute into the
7130 initialized for the static data member here. */
7131 finish_static_data_member_decl
7134 /*init_const_expr_p=*/false,
7135 /*asmspec_tree=*/NULL_TREE,
7137 if (DECL_INITIALIZED_IN_CLASS_P (r))
7138 check_static_variable_definition (r, TREE_TYPE (r));
7140 else if (TREE_CODE (r) == FIELD_DECL)
7142 /* Determine whether R has a valid type and can be
7143 completed later. If R is invalid, then it is
7144 replaced by error_mark_node so that it will not be
7145 added to TYPE_FIELDS. */
7146 tree rtype = TREE_TYPE (r);
7147 if (can_complete_type_without_circularity (rtype))
7148 complete_type (rtype);
7150 if (!COMPLETE_TYPE_P (rtype))
7152 cxx_incomplete_type_error (r, rtype);
7153 r = error_mark_node;
7157 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
7158 such a thing will already have been added to the field
7159 list by tsubst_enum in finish_member_declaration in the
7160 CLASSTYPE_NESTED_UTDS case above. */
7161 if (!(TREE_CODE (r) == TYPE_DECL
7162 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
7163 && DECL_ARTIFICIAL (r)))
7165 set_current_access_from_decl (r);
7166 finish_member_declaration (r);
7173 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
7175 /* Build new CLASSTYPE_FRIEND_CLASSES. */
7177 tree friend_type = t;
7178 bool adjust_processing_template_decl = false;
7180 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7182 /* template <class T> friend class C; */
7183 friend_type = tsubst_friend_class (friend_type, args);
7184 adjust_processing_template_decl = true;
7186 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
7188 /* template <class T> friend class C::D; */
7189 friend_type = tsubst (friend_type, args,
7190 tf_warning_or_error, NULL_TREE);
7191 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7192 friend_type = TREE_TYPE (friend_type);
7193 adjust_processing_template_decl = true;
7195 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
7197 /* This could be either
7201 when dependent_type_p is false or
7203 template <class U> friend class T::C;
7206 friend_type = tsubst (friend_type, args,
7207 tf_warning_or_error, NULL_TREE);
7208 /* Bump processing_template_decl for correct
7209 dependent_type_p calculation. */
7210 ++processing_template_decl;
7211 if (dependent_type_p (friend_type))
7212 adjust_processing_template_decl = true;
7213 --processing_template_decl;
7215 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
7216 && hidden_name_p (TYPE_NAME (friend_type)))
7220 where C hasn't been declared yet. Let's lookup name
7221 from namespace scope directly, bypassing any name that
7222 come from dependent base class. */
7223 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
7225 /* The call to xref_tag_from_type does injection for friend
7227 push_nested_namespace (ns);
7229 xref_tag_from_type (friend_type, NULL_TREE,
7230 /*tag_scope=*/ts_current);
7231 pop_nested_namespace (ns);
7233 else if (uses_template_parms (friend_type))
7234 /* friend class C<T>; */
7235 friend_type = tsubst (friend_type, args,
7236 tf_warning_or_error, NULL_TREE);
7241 where C is already declared or
7243 friend class C<int>;
7245 We don't have to do anything in these cases. */
7247 if (adjust_processing_template_decl)
7248 /* Trick make_friend_class into realizing that the friend
7249 we're adding is a template, not an ordinary class. It's
7250 important that we use make_friend_class since it will
7251 perform some error-checking and output cross-reference
7253 ++processing_template_decl;
7255 if (friend_type != error_mark_node)
7256 make_friend_class (type, friend_type, /*complain=*/false);
7258 if (adjust_processing_template_decl)
7259 --processing_template_decl;
7263 /* Build new DECL_FRIENDLIST. */
7266 /* The file and line for this declaration, to
7267 assist in error message reporting. Since we
7268 called push_tinst_level above, we don't need to
7270 input_location = DECL_SOURCE_LOCATION (t);
7272 if (TREE_CODE (t) == TEMPLATE_DECL)
7274 ++processing_template_decl;
7275 push_deferring_access_checks (dk_no_check);
7278 r = tsubst_friend_function (t, args);
7279 add_friend (type, r, /*complain=*/false);
7280 if (TREE_CODE (t) == TEMPLATE_DECL)
7282 pop_deferring_access_checks ();
7283 --processing_template_decl;
7289 /* Set the file and line number information to whatever is given for
7290 the class itself. This puts error messages involving generated
7291 implicit functions at a predictable point, and the same point
7292 that would be used for non-template classes. */
7293 input_location = DECL_SOURCE_LOCATION (typedecl);
7295 unreverse_member_declarations (type);
7296 finish_struct_1 (type);
7297 TYPE_BEING_DEFINED (type) = 0;
7299 /* Now that the class is complete, instantiate default arguments for
7300 any member functions. We don't do this earlier because the
7301 default arguments may reference members of the class. */
7302 if (!PRIMARY_TEMPLATE_P (templ))
7303 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
7304 if (TREE_CODE (t) == FUNCTION_DECL
7305 /* Implicitly generated member functions will not have template
7306 information; they are not instantiations, but instead are
7307 created "fresh" for each instantiation. */
7308 && DECL_TEMPLATE_INFO (t))
7309 tsubst_default_arguments (t);
7311 pop_nested_class ();
7312 pop_from_top_level ();
7313 pop_deferring_access_checks ();
7316 /* The vtable for a template class can be emitted in any translation
7317 unit in which the class is instantiated. When there is no key
7318 method, however, finish_struct_1 will already have added TYPE to
7319 the keyed_classes list. */
7320 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
7321 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
7327 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7333 else if (TYPE_P (t))
7334 r = tsubst (t, args, complain, in_decl);
7337 r = tsubst_expr (t, args, complain, in_decl,
7338 /*integral_constant_expression_p=*/true);
7339 r = fold_non_dependent_expr (r);
7344 /* Substitute ARGS into T, which is an pack expansion
7345 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
7346 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
7347 (if only a partial substitution could be performed) or
7348 ERROR_MARK_NODE if there was an error. */
7350 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
7354 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
7355 tree first_arg_pack; int i, len = -1;
7359 gcc_assert (PACK_EXPANSION_P (t));
7360 pattern = PACK_EXPANSION_PATTERN (t);
7362 /* Determine the argument packs that will instantiate the parameter
7363 packs used in the expansion expression. While we're at it,
7364 compute the number of arguments to be expanded and make sure it
7366 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
7367 pack = TREE_CHAIN (pack))
7369 tree parm_pack = TREE_VALUE (pack);
7370 tree arg_pack = NULL_TREE;
7371 tree orig_arg = NULL_TREE;
7373 if (TREE_CODE (parm_pack) == PARM_DECL)
7374 arg_pack = retrieve_local_specialization (parm_pack);
7377 int level, idx, levels;
7378 template_parm_level_and_index (parm_pack, &level, &idx);
7380 levels = TMPL_ARGS_DEPTH (args);
7381 if (level <= levels)
7382 arg_pack = TMPL_ARG (args, level, idx);
7385 orig_arg = arg_pack;
7386 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
7387 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
7389 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
7390 /* This can only happen if we forget to expand an argument
7391 pack somewhere else. Just return an error, silently. */
7393 result = make_tree_vec (1);
7394 TREE_VEC_ELT (result, 0) = error_mark_node;
7399 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
7400 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
7402 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
7403 tree pattern = PACK_EXPANSION_PATTERN (expansion);
7404 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
7405 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
7406 /* The argument pack that the parameter maps to is just an
7407 expansion of the parameter itself, such as one would
7408 find in the implicit typedef of a class inside the
7409 class itself. Consider this parameter "unsubstituted",
7410 so that we will maintain the outer pack expansion. */
7411 arg_pack = NULL_TREE;
7417 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
7419 /* It's all-or-nothing with incomplete argument packs. */
7420 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7421 return error_mark_node;
7423 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7429 first_arg_pack = arg_pack;
7431 else if (len != my_len)
7433 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
7434 error ("mismatched argument pack lengths while expanding "
7438 error ("mismatched argument pack lengths while expanding "
7441 return error_mark_node;
7444 /* Keep track of the parameter packs and their corresponding
7446 packs = tree_cons (parm_pack, arg_pack, packs);
7447 TREE_TYPE (packs) = orig_arg;
7450 /* We can't substitute for this parameter pack. */
7451 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
7453 unsubstituted_packs);
7456 /* We cannot expand this expansion expression, because we don't have
7457 all of the argument packs we need. Substitute into the pattern
7458 and return a PACK_EXPANSION_*. The caller will need to deal with
7460 if (unsubstituted_packs)
7461 return make_pack_expansion (tsubst (pattern, args, complain,
7464 /* We could not find any argument packs that work. */
7466 return error_mark_node;
7468 /* For each argument in each argument pack, substitute into the
7470 result = make_tree_vec (len + incomplete);
7471 for (i = 0; i < len + incomplete; ++i)
7473 /* For parameter pack, change the substitution of the parameter
7474 pack to the ith argument in its argument pack, then expand
7476 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7478 tree parm = TREE_PURPOSE (pack);
7480 if (TREE_CODE (parm) == PARM_DECL)
7482 /* Select the Ith argument from the pack. */
7483 tree arg = make_node (ARGUMENT_PACK_SELECT);
7484 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
7485 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
7487 register_local_specialization (arg, parm);
7493 template_parm_level_and_index (parm, &level, &idx);
7497 /* Select the Ith argument from the pack. */
7498 value = make_node (ARGUMENT_PACK_SELECT);
7499 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
7500 ARGUMENT_PACK_SELECT_INDEX (value) = i;
7503 /* Update the corresponding argument. */
7504 TMPL_ARG (args, level, idx) = value;
7508 /* Substitute into the PATTERN with the altered arguments. */
7509 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
7510 TREE_VEC_ELT (result, i) =
7511 tsubst_expr (pattern, args, complain, in_decl,
7512 /*integral_constant_expression_p=*/false);
7514 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
7517 /* When we have incomplete argument packs, the last "expanded"
7518 result is itself a pack expansion, which allows us
7519 to deduce more arguments. */
7520 TREE_VEC_ELT (result, i) =
7521 make_pack_expansion (TREE_VEC_ELT (result, i));
7523 if (TREE_VEC_ELT (result, i) == error_mark_node)
7525 result = error_mark_node;
7530 /* Update ARGS to restore the substitution from parameter packs to
7531 their argument packs. */
7532 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7534 tree parm = TREE_PURPOSE (pack);
7536 if (TREE_CODE (parm) == PARM_DECL)
7537 register_local_specialization (TREE_TYPE (pack), parm);
7541 template_parm_level_and_index (parm, &level, &idx);
7543 /* Update the corresponding argument. */
7544 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
7545 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
7548 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
7555 /* Substitute ARGS into the vector or list of template arguments T. */
7558 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7561 int len = TREE_VEC_LENGTH (t);
7562 int need_new = 0, i, expanded_len_adjust = 0, out;
7563 tree *elts = (tree *) alloca (len * sizeof (tree));
7565 for (i = 0; i < len; i++)
7567 tree orig_arg = TREE_VEC_ELT (t, i);
7570 if (TREE_CODE (orig_arg) == TREE_VEC)
7571 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
7572 else if (PACK_EXPANSION_P (orig_arg))
7574 /* Substitute into an expansion expression. */
7575 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
7577 if (TREE_CODE (new_arg) == TREE_VEC)
7578 /* Add to the expanded length adjustment the number of
7579 expanded arguments. We subtract one from this
7580 measurement, because the argument pack expression
7581 itself is already counted as 1 in
7582 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
7583 the argument pack is empty. */
7584 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
7586 else if (ARGUMENT_PACK_P (orig_arg))
7588 /* Substitute into each of the arguments. */
7589 new_arg = make_node (TREE_CODE (orig_arg));
7591 SET_ARGUMENT_PACK_ARGS (
7593 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
7594 args, complain, in_decl));
7596 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
7597 new_arg = error_mark_node;
7599 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
7600 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
7602 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
7604 if (TREE_TYPE (new_arg) == error_mark_node)
7605 new_arg = error_mark_node;
7609 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
7611 if (new_arg == error_mark_node)
7612 return error_mark_node;
7615 if (new_arg != orig_arg)
7622 /* Make space for the expanded arguments coming from template
7624 t = make_tree_vec (len + expanded_len_adjust);
7625 for (i = 0, out = 0; i < len; i++)
7627 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
7628 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
7629 && TREE_CODE (elts[i]) == TREE_VEC)
7633 /* Now expand the template argument pack "in place". */
7634 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
7635 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
7639 TREE_VEC_ELT (t, out) = elts[i];
7647 /* Return the result of substituting ARGS into the template parameters
7648 given by PARMS. If there are m levels of ARGS and m + n levels of
7649 PARMS, then the result will contain n levels of PARMS. For
7650 example, if PARMS is `template <class T> template <class U>
7651 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
7652 result will be `template <int*, double, class V>'. */
7655 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
7660 /* When substituting into a template, we must set
7661 PROCESSING_TEMPLATE_DECL as the template parameters may be
7662 dependent if they are based on one-another, and the dependency
7663 predicates are short-circuit outside of templates. */
7664 ++processing_template_decl;
7666 for (new_parms = &r;
7667 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
7668 new_parms = &(TREE_CHAIN (*new_parms)),
7669 parms = TREE_CHAIN (parms))
7672 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
7675 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
7681 if (parms == error_mark_node)
7684 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
7686 if (tuple == error_mark_node)
7689 default_value = TREE_PURPOSE (tuple);
7690 parm_decl = TREE_VALUE (tuple);
7692 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
7693 if (TREE_CODE (parm_decl) == PARM_DECL
7694 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
7695 parm_decl = error_mark_node;
7696 default_value = tsubst_template_arg (default_value, args,
7697 complain, NULL_TREE);
7699 tuple = build_tree_list (default_value, parm_decl);
7700 TREE_VEC_ELT (new_vec, i) = tuple;
7704 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
7705 - TMPL_ARGS_DEPTH (args)),
7706 new_vec, NULL_TREE);
7709 --processing_template_decl;
7714 /* Substitute the ARGS into the indicated aggregate (or enumeration)
7715 type T. If T is not an aggregate or enumeration type, it is
7716 handled as if by tsubst. IN_DECL is as for tsubst. If
7717 ENTERING_SCOPE is nonzero, T is the context for a template which
7718 we are presently tsubst'ing. Return the substituted value. */
7721 tsubst_aggr_type (tree t,
7723 tsubst_flags_t complain,
7730 switch (TREE_CODE (t))
7733 if (TYPE_PTRMEMFUNC_P (t))
7734 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
7736 /* Else fall through. */
7739 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
7744 bool saved_skip_evaluation;
7746 /* In "sizeof(X<I>)" we need to evaluate "I". */
7747 saved_skip_evaluation = skip_evaluation;
7748 skip_evaluation = false;
7750 /* First, determine the context for the type we are looking
7752 context = TYPE_CONTEXT (t);
7755 context = tsubst_aggr_type (context, args, complain,
7756 in_decl, /*entering_scope=*/1);
7757 /* If context is a nested class inside a class template,
7758 it may still need to be instantiated (c++/33959). */
7759 if (TYPE_P (context))
7760 context = complete_type (context);
7763 /* Then, figure out what arguments are appropriate for the
7764 type we are trying to find. For example, given:
7766 template <class T> struct S;
7767 template <class T, class U> void f(T, U) { S<U> su; }
7769 and supposing that we are instantiating f<int, double>,
7770 then our ARGS will be {int, double}, but, when looking up
7771 S we only want {double}. */
7772 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
7774 if (argvec == error_mark_node)
7775 r = error_mark_node;
7778 r = lookup_template_class (t, argvec, in_decl, context,
7779 entering_scope, complain);
7780 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7783 skip_evaluation = saved_skip_evaluation;
7788 /* This is not a template type, so there's nothing to do. */
7792 return tsubst (t, args, complain, in_decl);
7796 /* Substitute into the default argument ARG (a default argument for
7797 FN), which has the indicated TYPE. */
7800 tsubst_default_argument (tree fn, tree type, tree arg)
7802 tree saved_class_ptr = NULL_TREE;
7803 tree saved_class_ref = NULL_TREE;
7805 /* This default argument came from a template. Instantiate the
7806 default argument here, not in tsubst. In the case of
7815 we must be careful to do name lookup in the scope of S<T>,
7816 rather than in the current class. */
7817 push_access_scope (fn);
7818 /* The "this" pointer is not valid in a default argument. */
7821 saved_class_ptr = current_class_ptr;
7822 cp_function_chain->x_current_class_ptr = NULL_TREE;
7823 saved_class_ref = current_class_ref;
7824 cp_function_chain->x_current_class_ref = NULL_TREE;
7827 push_deferring_access_checks(dk_no_deferred);
7828 /* The default argument expression may cause implicitly defined
7829 member functions to be synthesized, which will result in garbage
7830 collection. We must treat this situation as if we were within
7831 the body of function so as to avoid collecting live data on the
7834 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
7835 tf_warning_or_error, NULL_TREE,
7836 /*integral_constant_expression_p=*/false);
7838 pop_deferring_access_checks();
7840 /* Restore the "this" pointer. */
7843 cp_function_chain->x_current_class_ptr = saved_class_ptr;
7844 cp_function_chain->x_current_class_ref = saved_class_ref;
7847 pop_access_scope (fn);
7849 /* Make sure the default argument is reasonable. */
7850 arg = check_default_argument (type, arg);
7855 /* Substitute into all the default arguments for FN. */
7858 tsubst_default_arguments (tree fn)
7863 tmpl_args = DECL_TI_ARGS (fn);
7865 /* If this function is not yet instantiated, we certainly don't need
7866 its default arguments. */
7867 if (uses_template_parms (tmpl_args))
7870 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
7872 arg = TREE_CHAIN (arg))
7873 if (TREE_PURPOSE (arg))
7874 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
7876 TREE_PURPOSE (arg));
7879 /* Substitute the ARGS into the T, which is a _DECL. Return the
7880 result of the substitution. Issue error and warning messages under
7881 control of COMPLAIN. */
7884 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
7886 location_t saved_loc;
7890 /* Set the filename and linenumber to improve error-reporting. */
7891 saved_loc = input_location;
7892 input_location = DECL_SOURCE_LOCATION (t);
7894 switch (TREE_CODE (t))
7898 /* We can get here when processing a member function template,
7899 member class template, and template template parameter of
7900 a template class. */
7901 tree decl = DECL_TEMPLATE_RESULT (t);
7906 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7908 /* Template template parameter is treated here. */
7909 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7910 if (new_type == error_mark_node)
7911 return error_mark_node;
7914 TREE_CHAIN (r) = NULL_TREE;
7915 TREE_TYPE (r) = new_type;
7916 DECL_TEMPLATE_RESULT (r)
7917 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
7918 DECL_TEMPLATE_PARMS (r)
7919 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
7921 TYPE_NAME (new_type) = r;
7925 /* We might already have an instance of this template.
7926 The ARGS are for the surrounding class type, so the
7927 full args contain the tsubst'd args for the context,
7928 plus the innermost args from the template decl. */
7929 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
7930 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
7931 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
7932 /* Because this is a template, the arguments will still be
7933 dependent, even after substitution. If
7934 PROCESSING_TEMPLATE_DECL is not set, the dependency
7935 predicates will short-circuit. */
7936 ++processing_template_decl;
7937 full_args = tsubst_template_args (tmpl_args, args,
7939 --processing_template_decl;
7940 if (full_args == error_mark_node)
7941 return error_mark_node;
7943 /* tsubst_template_args doesn't copy the vector if
7944 nothing changed. But, *something* should have
7946 gcc_assert (full_args != tmpl_args);
7948 spec = retrieve_specialization (t, full_args,
7949 /*class_specializations_p=*/true);
7950 if (spec != NULL_TREE)
7956 /* Make a new template decl. It will be similar to the
7957 original, but will record the current template arguments.
7958 We also create a new function declaration, which is just
7959 like the old one, but points to this new template, rather
7960 than the old one. */
7962 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
7963 TREE_CHAIN (r) = NULL_TREE;
7965 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
7967 if (TREE_CODE (decl) == TYPE_DECL)
7970 ++processing_template_decl;
7971 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7972 --processing_template_decl;
7973 if (new_type == error_mark_node)
7974 return error_mark_node;
7976 TREE_TYPE (r) = new_type;
7977 CLASSTYPE_TI_TEMPLATE (new_type) = r;
7978 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
7979 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
7980 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
7985 ++processing_template_decl;
7986 new_decl = tsubst (decl, args, complain, in_decl);
7987 --processing_template_decl;
7988 if (new_decl == error_mark_node)
7989 return error_mark_node;
7991 DECL_TEMPLATE_RESULT (r) = new_decl;
7992 DECL_TI_TEMPLATE (new_decl) = r;
7993 TREE_TYPE (r) = TREE_TYPE (new_decl);
7994 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
7995 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
7998 SET_DECL_IMPLICIT_INSTANTIATION (r);
7999 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
8000 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
8002 /* The template parameters for this new template are all the
8003 template parameters for the old template, except the
8004 outermost level of parameters. */
8005 DECL_TEMPLATE_PARMS (r)
8006 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8009 if (PRIMARY_TEMPLATE_P (t))
8010 DECL_PRIMARY_TEMPLATE (r) = r;
8012 if (TREE_CODE (decl) != TYPE_DECL)
8013 /* Record this non-type partial instantiation. */
8014 register_specialization (r, t,
8015 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
8023 tree argvec = NULL_TREE;
8031 /* Nobody should be tsubst'ing into non-template functions. */
8032 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
8034 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
8039 /* If T is not dependent, just return it. We have to
8040 increment PROCESSING_TEMPLATE_DECL because
8041 value_dependent_expression_p assumes that nothing is
8042 dependent when PROCESSING_TEMPLATE_DECL is zero. */
8043 ++processing_template_decl;
8044 dependent_p = value_dependent_expression_p (t);
8045 --processing_template_decl;
8049 /* Calculate the most general template of which R is a
8050 specialization, and the complete set of arguments used to
8052 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
8053 argvec = tsubst_template_args (DECL_TI_ARGS
8054 (DECL_TEMPLATE_RESULT (gen_tmpl)),
8055 args, complain, in_decl);
8057 /* Check to see if we already have this specialization. */
8058 spec = retrieve_specialization (gen_tmpl, argvec,
8059 /*class_specializations_p=*/false);
8067 /* We can see more levels of arguments than parameters if
8068 there was a specialization of a member template, like
8071 template <class T> struct S { template <class U> void f(); }
8072 template <> template <class U> void S<int>::f(U);
8074 Here, we'll be substituting into the specialization,
8075 because that's where we can find the code we actually
8076 want to generate, but we'll have enough arguments for
8077 the most general template.
8079 We also deal with the peculiar case:
8081 template <class T> struct S {
8082 template <class U> friend void f();
8084 template <class U> void f() {}
8086 template void f<double>();
8088 Here, the ARGS for the instantiation of will be {int,
8089 double}. But, we only need as many ARGS as there are
8090 levels of template parameters in CODE_PATTERN. We are
8091 careful not to get fooled into reducing the ARGS in
8094 template <class T> struct S { template <class U> void f(U); }
8095 template <class T> template <> void S<T>::f(int) {}
8097 which we can spot because the pattern will be a
8098 specialization in this case. */
8099 args_depth = TMPL_ARGS_DEPTH (args);
8101 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
8102 if (args_depth > parms_depth
8103 && !DECL_TEMPLATE_SPECIALIZATION (t))
8104 args = get_innermost_template_args (args, parms_depth);
8108 /* This special case arises when we have something like this:
8110 template <class T> struct S {
8111 friend void f<int>(int, double);
8114 Here, the DECL_TI_TEMPLATE for the friend declaration
8115 will be an IDENTIFIER_NODE. We are being called from
8116 tsubst_friend_function, and we want only to create a
8117 new decl (R) with appropriate types so that we can call
8118 determine_specialization. */
8119 gen_tmpl = NULL_TREE;
8122 if (DECL_CLASS_SCOPE_P (t))
8124 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
8128 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
8129 complain, t, /*entering_scope=*/1);
8134 ctx = DECL_CONTEXT (t);
8136 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8137 if (type == error_mark_node)
8138 return error_mark_node;
8140 /* We do NOT check for matching decls pushed separately at this
8141 point, as they may not represent instantiations of this
8142 template, and in any case are considered separate under the
8145 DECL_USE_TEMPLATE (r) = 0;
8146 TREE_TYPE (r) = type;
8147 /* Clear out the mangled name and RTL for the instantiation. */
8148 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8149 SET_DECL_RTL (r, NULL_RTX);
8150 DECL_INITIAL (r) = NULL_TREE;
8151 DECL_CONTEXT (r) = ctx;
8153 if (member && DECL_CONV_FN_P (r))
8154 /* Type-conversion operator. Reconstruct the name, in
8155 case it's the name of one of the template's parameters. */
8156 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
8158 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
8160 DECL_RESULT (r) = NULL_TREE;
8162 TREE_STATIC (r) = 0;
8163 TREE_PUBLIC (r) = TREE_PUBLIC (t);
8164 DECL_EXTERNAL (r) = 1;
8165 /* If this is an instantiation of a function with internal
8166 linkage, we already know what object file linkage will be
8167 assigned to the instantiation. */
8168 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
8169 DECL_DEFER_OUTPUT (r) = 0;
8170 TREE_CHAIN (r) = NULL_TREE;
8171 DECL_PENDING_INLINE_INFO (r) = 0;
8172 DECL_PENDING_INLINE_P (r) = 0;
8173 DECL_SAVED_TREE (r) = NULL_TREE;
8175 if (DECL_CLONED_FUNCTION (r))
8177 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
8179 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
8180 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
8183 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
8184 this in the special friend case mentioned above where
8185 GEN_TMPL is NULL. */
8188 DECL_TEMPLATE_INFO (r)
8189 = tree_cons (gen_tmpl, argvec, NULL_TREE);
8190 SET_DECL_IMPLICIT_INSTANTIATION (r);
8191 register_specialization (r, gen_tmpl, argvec, false);
8193 /* We're not supposed to instantiate default arguments
8194 until they are called, for a template. But, for a
8197 template <class T> void f ()
8198 { extern void g(int i = T()); }
8200 we should do the substitution when the template is
8201 instantiated. We handle the member function case in
8202 instantiate_class_template since the default arguments
8203 might refer to other members of the class. */
8205 && !PRIMARY_TEMPLATE_P (gen_tmpl)
8206 && !uses_template_parms (argvec))
8207 tsubst_default_arguments (r);
8210 DECL_TEMPLATE_INFO (r) = NULL_TREE;
8212 /* Copy the list of befriending classes. */
8213 for (friends = &DECL_BEFRIENDING_CLASSES (r);
8215 friends = &TREE_CHAIN (*friends))
8217 *friends = copy_node (*friends);
8218 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
8223 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
8225 maybe_retrofit_in_chrg (r);
8226 if (DECL_CONSTRUCTOR_P (r))
8227 grok_ctor_properties (ctx, r);
8228 /* If this is an instantiation of a member template, clone it.
8229 If it isn't, that'll be handled by
8230 clone_constructors_and_destructors. */
8231 if (PRIMARY_TEMPLATE_P (gen_tmpl))
8232 clone_function_decl (r, /*update_method_vec_p=*/0);
8234 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r))
8235 && !grok_op_properties (r, (complain & tf_error) != 0))
8236 return error_mark_node;
8238 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
8239 SET_DECL_FRIEND_CONTEXT (r,
8240 tsubst (DECL_FRIEND_CONTEXT (t),
8241 args, complain, in_decl));
8243 /* Possibly limit visibility based on template args. */
8244 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8245 if (DECL_VISIBILITY_SPECIFIED (t))
8247 DECL_VISIBILITY_SPECIFIED (r) = 0;
8249 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8251 determine_visibility (r);
8253 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8254 args, complain, in_decl);
8260 tree type = NULL_TREE;
8262 tree expanded_types = NULL_TREE;
8263 tree prev_r = NULL_TREE;
8264 tree first_r = NULL_TREE;
8266 if (FUNCTION_PARAMETER_PACK_P (t))
8268 /* If there is a local specialization that isn't a
8269 parameter pack, it means that we're doing a "simple"
8270 substitution from inside tsubst_pack_expansion. Just
8271 return the local specialization (which will be a single
8273 tree spec = retrieve_local_specialization (t);
8275 && TREE_CODE (spec) == PARM_DECL
8276 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
8279 /* Expand the TYPE_PACK_EXPANSION that provides the types for
8280 the parameters in this function parameter pack. */
8281 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
8283 if (TREE_CODE (expanded_types) == TREE_VEC)
8285 len = TREE_VEC_LENGTH (expanded_types);
8287 /* Zero-length parameter packs are boring. Just substitute
8290 return tsubst (TREE_CHAIN (t), args, complain,
8295 /* All we did was update the type. Make a note of that. */
8296 type = expanded_types;
8297 expanded_types = NULL_TREE;
8301 /* Loop through all of the parameter's we'll build. When T is
8302 a function parameter pack, LEN is the number of expanded
8303 types in EXPANDED_TYPES; otherwise, LEN is 1. */
8305 for (i = 0; i < len; ++i)
8309 if (DECL_TEMPLATE_PARM_P (t))
8310 SET_DECL_TEMPLATE_PARM_P (r);
8313 /* We're on the Ith parameter of the function parameter
8316 /* Get the Ith type. */
8317 type = TREE_VEC_ELT (expanded_types, i);
8320 /* Rename the parameter to include the index. */
8322 make_ith_pack_parameter_name (DECL_NAME (r), i);
8325 /* We're dealing with a normal parameter. */
8326 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8328 type = type_decays_to (type);
8329 TREE_TYPE (r) = type;
8330 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8332 if (DECL_INITIAL (r))
8334 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
8335 DECL_INITIAL (r) = TREE_TYPE (r);
8337 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
8341 DECL_CONTEXT (r) = NULL_TREE;
8343 if (!DECL_TEMPLATE_PARM_P (r))
8344 DECL_ARG_TYPE (r) = type_passed_as (type);
8346 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8347 args, complain, in_decl);
8349 /* Keep track of the first new parameter we
8350 generate. That's what will be returned to the
8355 /* Build a proper chain of parameters when substituting
8356 into a function parameter pack. */
8358 TREE_CHAIN (prev_r) = r;
8362 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
8363 complain, TREE_CHAIN (t));
8365 /* FIRST_R contains the start of the chain we've built. */
8375 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8376 if (type == error_mark_node)
8377 return error_mark_node;
8378 TREE_TYPE (r) = type;
8379 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8381 /* DECL_INITIAL gives the number of bits in a bit-field. */
8383 = tsubst_expr (DECL_INITIAL (t), args,
8385 /*integral_constant_expression_p=*/true);
8386 /* We don't have to set DECL_CONTEXT here; it is set by
8387 finish_member_declaration. */
8388 TREE_CHAIN (r) = NULL_TREE;
8389 if (VOID_TYPE_P (type))
8390 error ("instantiation of %q+D as type %qT", r, type);
8392 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8393 args, complain, in_decl);
8398 /* We reach here only for member using decls. */
8399 if (DECL_DEPENDENT_P (t))
8401 r = do_class_using_decl
8402 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
8403 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
8405 r = error_mark_node;
8410 TREE_CHAIN (r) = NULL_TREE;
8417 tree argvec = NULL_TREE;
8418 tree gen_tmpl = NULL_TREE;
8420 tree tmpl = NULL_TREE;
8422 tree type = NULL_TREE;
8425 if (TREE_CODE (t) == TYPE_DECL
8426 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
8428 /* If this is the canonical decl, we don't have to
8429 mess with instantiations, and often we can't (for
8430 typename, template type parms and such). Note that
8431 TYPE_NAME is not correct for the above test if
8432 we've copied the type for a typedef. */
8433 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8434 if (type == error_mark_node)
8435 return error_mark_node;
8436 r = TYPE_NAME (type);
8440 /* Check to see if we already have the specialization we
8443 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
8445 /* T is a static data member or namespace-scope entity.
8446 We have to substitute into namespace-scope variables
8447 (even though such entities are never templates) because
8450 template <class T> void f() { extern T t; }
8452 where the entity referenced is not known until
8453 instantiation time. */
8455 ctx = DECL_CONTEXT (t);
8456 if (DECL_CLASS_SCOPE_P (t))
8458 ctx = tsubst_aggr_type (ctx, args,
8460 in_decl, /*entering_scope=*/1);
8461 /* If CTX is unchanged, then T is in fact the
8462 specialization we want. That situation occurs when
8463 referencing a static data member within in its own
8464 class. We can use pointer equality, rather than
8465 same_type_p, because DECL_CONTEXT is always
8467 if (ctx == DECL_CONTEXT (t))
8473 tmpl = DECL_TI_TEMPLATE (t);
8474 gen_tmpl = most_general_template (tmpl);
8475 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
8476 spec = (retrieve_specialization
8478 /*class_specializations_p=*/false));
8483 /* A local variable. */
8485 /* Subsequent calls to pushdecl will fill this in. */
8487 spec = retrieve_local_specialization (t);
8489 /* If we already have the specialization we need, there is
8490 nothing more to do. */
8497 /* Create a new node for the specialization we need. */
8499 if (type == NULL_TREE)
8500 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8501 if (TREE_CODE (r) == VAR_DECL)
8503 /* Even if the original location is out of scope, the
8504 newly substituted one is not. */
8505 DECL_DEAD_FOR_LOCAL (r) = 0;
8506 DECL_INITIALIZED_P (r) = 0;
8507 DECL_TEMPLATE_INSTANTIATED (r) = 0;
8508 if (type == error_mark_node)
8509 return error_mark_node;
8510 if (TREE_CODE (type) == FUNCTION_TYPE)
8512 /* It may seem that this case cannot occur, since:
8517 declares a function, not a variable. However:
8520 template <typename T> void g() { T t; }
8521 template void g<f>();
8523 is an attempt to declare a variable with function
8525 error ("variable %qD has function type",
8526 /* R is not yet sufficiently initialized, so we
8527 just use its name. */
8529 return error_mark_node;
8531 type = complete_type (type);
8532 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
8533 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
8534 type = check_var_type (DECL_NAME (r), type);
8536 if (DECL_HAS_VALUE_EXPR_P (t))
8538 tree ve = DECL_VALUE_EXPR (t);
8539 ve = tsubst_expr (ve, args, complain, in_decl,
8540 /*constant_expression_p=*/false);
8541 SET_DECL_VALUE_EXPR (r, ve);
8544 else if (DECL_SELF_REFERENCE_P (t))
8545 SET_DECL_SELF_REFERENCE_P (r);
8546 TREE_TYPE (r) = type;
8547 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8548 DECL_CONTEXT (r) = ctx;
8549 /* Clear out the mangled name and RTL for the instantiation. */
8550 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8551 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8552 SET_DECL_RTL (r, NULL_RTX);
8553 /* The initializer must not be expanded until it is required;
8555 DECL_INITIAL (r) = NULL_TREE;
8556 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8557 SET_DECL_RTL (r, NULL_RTX);
8558 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
8559 if (TREE_CODE (r) == VAR_DECL)
8561 /* Possibly limit visibility based on template args. */
8562 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8563 if (DECL_VISIBILITY_SPECIFIED (t))
8565 DECL_VISIBILITY_SPECIFIED (r) = 0;
8567 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8569 determine_visibility (r);
8571 /* Preserve a typedef that names a type. */
8572 else if (TREE_CODE (r) == TYPE_DECL
8573 && DECL_ORIGINAL_TYPE (t)
8574 && type != error_mark_node)
8576 DECL_ORIGINAL_TYPE (r) = tsubst (DECL_ORIGINAL_TYPE (t),
8577 args, complain, in_decl);
8578 TREE_TYPE (r) = type = build_variant_type_copy (type);
8579 TYPE_NAME (type) = r;
8584 /* A static data member declaration is always marked
8585 external when it is declared in-class, even if an
8586 initializer is present. We mimic the non-template
8588 DECL_EXTERNAL (r) = 1;
8590 register_specialization (r, gen_tmpl, argvec, false);
8591 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
8592 SET_DECL_IMPLICIT_INSTANTIATION (r);
8595 register_local_specialization (r, t);
8597 TREE_CHAIN (r) = NULL_TREE;
8599 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
8600 (int) ATTR_FLAG_TYPE_IN_PLACE,
8601 args, complain, in_decl);
8610 /* Restore the file and line information. */
8611 input_location = saved_loc;
8616 /* Substitute into the ARG_TYPES of a function type. */
8619 tsubst_arg_types (tree arg_types,
8621 tsubst_flags_t complain,
8624 tree remaining_arg_types;
8625 tree type = NULL_TREE;
8627 tree expanded_args = NULL_TREE;
8630 if (!arg_types || arg_types == void_list_node)
8633 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
8634 args, complain, in_decl);
8635 if (remaining_arg_types == error_mark_node)
8636 return error_mark_node;
8638 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
8640 /* For a pack expansion, perform substitution on the
8641 entire expression. Later on, we'll handle the arguments
8643 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
8644 args, complain, in_decl);
8646 if (TREE_CODE (expanded_args) == TREE_VEC)
8647 /* So that we'll spin through the parameters, one by one. */
8648 i = TREE_VEC_LENGTH (expanded_args);
8651 /* We only partially substituted into the parameter
8652 pack. Our type is TYPE_PACK_EXPANSION. */
8653 type = expanded_args;
8654 expanded_args = NULL_TREE;
8662 type = TREE_VEC_ELT (expanded_args, i);
8664 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
8666 if (type == error_mark_node)
8667 return error_mark_node;
8668 if (VOID_TYPE_P (type))
8670 if (complain & tf_error)
8672 error ("invalid parameter type %qT", type);
8674 error ("in declaration %q+D", in_decl);
8676 return error_mark_node;
8679 /* Do array-to-pointer, function-to-pointer conversion, and ignore
8680 top-level qualifiers as required. */
8681 type = TYPE_MAIN_VARIANT (type_decays_to (type));
8683 /* We do not substitute into default arguments here. The standard
8684 mandates that they be instantiated only when needed, which is
8685 done in build_over_call. */
8686 default_arg = TREE_PURPOSE (arg_types);
8688 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
8690 /* We've instantiated a template before its default arguments
8691 have been parsed. This can happen for a nested template
8692 class, and is not an error unless we require the default
8693 argument in a call of this function. */
8694 remaining_arg_types =
8695 tree_cons (default_arg, type, remaining_arg_types);
8696 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
8697 remaining_arg_types);
8700 remaining_arg_types =
8701 hash_tree_cons (default_arg, type, remaining_arg_types);
8704 return remaining_arg_types;
8707 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
8708 *not* handle the exception-specification for FNTYPE, because the
8709 initial substitution of explicitly provided template parameters
8710 during argument deduction forbids substitution into the
8711 exception-specification:
8715 All references in the function type of the function template to the
8716 corresponding template parameters are replaced by the specified tem-
8717 plate argument values. If a substitution in a template parameter or
8718 in the function type of the function template results in an invalid
8719 type, type deduction fails. [Note: The equivalent substitution in
8720 exception specifications is done only when the function is instanti-
8721 ated, at which point a program is ill-formed if the substitution
8722 results in an invalid type.] */
8725 tsubst_function_type (tree t,
8727 tsubst_flags_t complain,
8734 /* The TYPE_CONTEXT is not used for function/method types. */
8735 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
8737 /* Substitute the return type. */
8738 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8739 if (return_type == error_mark_node)
8740 return error_mark_node;
8741 /* The standard does not presently indicate that creation of a
8742 function type with an invalid return type is a deduction failure.
8743 However, that is clearly analogous to creating an array of "void"
8744 or a reference to a reference. This is core issue #486. */
8745 if (TREE_CODE (return_type) == ARRAY_TYPE
8746 || TREE_CODE (return_type) == FUNCTION_TYPE)
8748 if (complain & tf_error)
8750 if (TREE_CODE (return_type) == ARRAY_TYPE)
8751 error ("function returning an array");
8753 error ("function returning a function");
8755 return error_mark_node;
8758 /* Substitute the argument types. */
8759 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
8761 if (arg_types == error_mark_node)
8762 return error_mark_node;
8764 /* Construct a new type node and return it. */
8765 if (TREE_CODE (t) == FUNCTION_TYPE)
8766 fntype = build_function_type (return_type, arg_types);
8769 tree r = TREE_TYPE (TREE_VALUE (arg_types));
8770 if (! MAYBE_CLASS_TYPE_P (r))
8774 Type deduction may fail for any of the following
8777 -- Attempting to create "pointer to member of T" when T
8778 is not a class type. */
8779 if (complain & tf_error)
8780 error ("creating pointer to member function of non-class type %qT",
8782 return error_mark_node;
8785 fntype = build_method_type_directly (r, return_type,
8786 TREE_CHAIN (arg_types));
8788 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
8789 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
8794 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
8795 ARGS into that specification, and return the substituted
8796 specification. If there is no specification, return NULL_TREE. */
8799 tsubst_exception_specification (tree fntype,
8801 tsubst_flags_t complain,
8807 specs = TYPE_RAISES_EXCEPTIONS (fntype);
8808 new_specs = NULL_TREE;
8811 if (! TREE_VALUE (specs))
8818 tree expanded_specs = NULL_TREE;
8820 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
8822 /* Expand the pack expansion type. */
8823 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
8827 if (expanded_specs == error_mark_node)
8828 return error_mark_node;
8829 else if (TREE_CODE (expanded_specs) == TREE_VEC)
8830 len = TREE_VEC_LENGTH (expanded_specs);
8833 /* We're substituting into a member template, so
8834 we got a TYPE_PACK_EXPANSION back. Add that
8835 expansion and move on. */
8836 gcc_assert (TREE_CODE (expanded_specs)
8837 == TYPE_PACK_EXPANSION);
8838 new_specs = add_exception_specifier (new_specs,
8841 specs = TREE_CHAIN (specs);
8846 for (i = 0; i < len; ++i)
8849 spec = TREE_VEC_ELT (expanded_specs, i);
8851 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
8852 if (spec == error_mark_node)
8854 new_specs = add_exception_specifier (new_specs, spec,
8858 specs = TREE_CHAIN (specs);
8864 /* Take the tree structure T and replace template parameters used
8865 therein with the argument vector ARGS. IN_DECL is an associated
8866 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
8867 Issue error and warning messages under control of COMPLAIN. Note
8868 that we must be relatively non-tolerant of extensions here, in
8869 order to preserve conformance; if we allow substitutions that
8870 should not be allowed, we may allow argument deductions that should
8871 not succeed, and therefore report ambiguous overload situations
8872 where there are none. In theory, we could allow the substitution,
8873 but indicate that it should have failed, and allow our caller to
8874 make sure that the right thing happens, but we don't try to do this
8877 This function is used for dealing with types, decls and the like;
8878 for expressions, use tsubst_expr or tsubst_copy. */
8881 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8885 if (t == NULL_TREE || t == error_mark_node
8886 || t == integer_type_node
8887 || t == void_type_node
8888 || t == char_type_node
8889 || t == unknown_type_node
8890 || TREE_CODE (t) == NAMESPACE_DECL)
8894 return tsubst_decl (t, args, complain);
8896 if (TREE_CODE (t) == IDENTIFIER_NODE)
8897 type = IDENTIFIER_TYPE_VALUE (t);
8899 type = TREE_TYPE (t);
8901 gcc_assert (type != unknown_type_node);
8903 /* Reuse typedefs. We need to do this to handle dependent attributes,
8904 such as attribute aligned. */
8907 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
8909 tree decl = TYPE_NAME (t);
8911 if (DECL_CLASS_SCOPE_P (decl)
8912 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
8913 && uses_template_parms (DECL_CONTEXT (decl)))
8915 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
8916 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
8917 r = retrieve_specialization (tmpl, gen_args, false);
8919 else if (DECL_FUNCTION_SCOPE_P (decl)
8920 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
8921 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
8922 r = retrieve_local_specialization (decl);
8924 /* The typedef is from a non-template context. */
8930 r = cp_build_qualified_type_real
8931 (r, cp_type_quals (t) | cp_type_quals (r),
8932 complain | tf_ignore_bad_quals);
8935 /* Else we must be instantiating the typedef, so fall through. */
8939 && TREE_CODE (t) != TYPENAME_TYPE
8940 && TREE_CODE (t) != IDENTIFIER_NODE
8941 && TREE_CODE (t) != FUNCTION_TYPE
8942 && TREE_CODE (t) != METHOD_TYPE)
8943 type = tsubst (type, args, complain, in_decl);
8944 if (type == error_mark_node)
8945 return error_mark_node;
8947 switch (TREE_CODE (t))
8952 return tsubst_aggr_type (t, args, complain, in_decl,
8953 /*entering_scope=*/0);
8956 case IDENTIFIER_NODE:
8968 if (t == integer_type_node)
8971 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
8972 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
8976 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
8978 max = tsubst_expr (omax, args, complain, in_decl,
8979 /*integral_constant_expression_p=*/false);
8980 max = fold_decl_constant_value (max);
8982 if (TREE_CODE (max) != INTEGER_CST
8983 && !at_function_scope_p ()
8984 && !value_dependent_expression_p (max))
8986 if (complain & tf_error)
8987 error ("array bound is not an integer constant");
8988 return error_mark_node;
8993 Type deduction may fail for any of the following
8996 Attempting to create an array with a size that is
8997 zero or negative. */
8998 if (integer_zerop (max) && !(complain & tf_error))
8999 /* We must fail if performing argument deduction (as
9000 indicated by the state of complain), so that
9001 another substitution can be found. */
9002 return error_mark_node;
9003 else if (TREE_CODE (max) == INTEGER_CST
9004 && INT_CST_LT (max, integer_zero_node))
9006 if (complain & tf_error)
9007 error ("creating array with negative size (%qE)", max);
9009 return error_mark_node;
9012 return compute_array_index_type (NULL_TREE, max);
9015 case TEMPLATE_TYPE_PARM:
9016 case TEMPLATE_TEMPLATE_PARM:
9017 case BOUND_TEMPLATE_TEMPLATE_PARM:
9018 case TEMPLATE_PARM_INDEX:
9023 tree arg = NULL_TREE;
9027 gcc_assert (TREE_VEC_LENGTH (args) > 0);
9028 template_parm_level_and_index (t, &level, &idx);
9030 levels = TMPL_ARGS_DEPTH (args);
9031 if (level <= levels)
9033 arg = TMPL_ARG (args, level, idx);
9035 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
9036 /* See through ARGUMENT_PACK_SELECT arguments. */
9037 arg = ARGUMENT_PACK_SELECT_ARG (arg);
9040 if (arg == error_mark_node)
9041 return error_mark_node;
9042 else if (arg != NULL_TREE)
9044 if (ARGUMENT_PACK_P (arg))
9045 /* If ARG is an argument pack, we don't actually want to
9046 perform a substitution here, because substitutions
9047 for argument packs are only done
9048 element-by-element. We can get to this point when
9049 substituting the type of a non-type template
9050 parameter pack, when that type actually contains
9051 template parameter packs from an outer template, e.g.,
9053 template<typename... Types> struct A {
9054 template<Types... Values> struct B { };
9058 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
9061 gcc_assert (TYPE_P (arg));
9063 /* cv-quals from the template are discarded when
9064 substituting in a function or reference type. */
9065 if (TREE_CODE (arg) == FUNCTION_TYPE
9066 || TREE_CODE (arg) == METHOD_TYPE
9067 || TREE_CODE (arg) == REFERENCE_TYPE)
9068 quals = cp_type_quals (arg);
9070 quals = cp_type_quals (arg) | cp_type_quals (t);
9072 return cp_build_qualified_type_real
9073 (arg, quals, complain | tf_ignore_bad_quals);
9075 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9077 /* We are processing a type constructed from a
9078 template template parameter. */
9079 tree argvec = tsubst (TYPE_TI_ARGS (t),
9080 args, complain, in_decl);
9081 if (argvec == error_mark_node)
9082 return error_mark_node;
9084 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
9085 are resolving nested-types in the signature of a
9086 member function templates. Otherwise ARG is a
9087 TEMPLATE_DECL and is the real template to be
9089 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
9090 arg = TYPE_NAME (arg);
9092 r = lookup_template_class (arg,
9095 /*entering_scope=*/0,
9097 return cp_build_qualified_type_real
9098 (r, TYPE_QUALS (t), complain);
9101 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
9106 /* This can happen during the attempted tsubst'ing in
9107 unify. This means that we don't yet have any information
9108 about the template parameter in question. */
9111 /* If we get here, we must have been looking at a parm for a
9112 more deeply nested template. Make a new version of this
9113 template parameter, but with a lower level. */
9114 switch (TREE_CODE (t))
9116 case TEMPLATE_TYPE_PARM:
9117 case TEMPLATE_TEMPLATE_PARM:
9118 case BOUND_TEMPLATE_TEMPLATE_PARM:
9119 if (cp_type_quals (t))
9121 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
9122 r = cp_build_qualified_type_real
9123 (r, cp_type_quals (t),
9124 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
9125 ? tf_ignore_bad_quals : 0));
9130 TEMPLATE_TYPE_PARM_INDEX (r)
9131 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
9132 r, levels, args, complain);
9133 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
9134 TYPE_MAIN_VARIANT (r) = r;
9135 TYPE_POINTER_TO (r) = NULL_TREE;
9136 TYPE_REFERENCE_TO (r) = NULL_TREE;
9138 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
9139 /* We have reduced the level of the template
9140 template parameter, but not the levels of its
9141 template parameters, so canonical_type_parameter
9142 will not be able to find the canonical template
9143 template parameter for this level. Thus, we
9144 require structural equality checking to compare
9145 TEMPLATE_TEMPLATE_PARMs. */
9146 SET_TYPE_STRUCTURAL_EQUALITY (r);
9147 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
9148 SET_TYPE_STRUCTURAL_EQUALITY (r);
9150 TYPE_CANONICAL (r) = canonical_type_parameter (r);
9152 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9154 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
9156 if (argvec == error_mark_node)
9157 return error_mark_node;
9159 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
9160 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
9165 case TEMPLATE_PARM_INDEX:
9166 r = reduce_template_parm_level (t, type, levels, args, complain);
9178 tree purpose, value, chain;
9180 if (t == void_list_node)
9183 purpose = TREE_PURPOSE (t);
9186 purpose = tsubst (purpose, args, complain, in_decl);
9187 if (purpose == error_mark_node)
9188 return error_mark_node;
9190 value = TREE_VALUE (t);
9193 value = tsubst (value, args, complain, in_decl);
9194 if (value == error_mark_node)
9195 return error_mark_node;
9197 chain = TREE_CHAIN (t);
9198 if (chain && chain != void_type_node)
9200 chain = tsubst (chain, args, complain, in_decl);
9201 if (chain == error_mark_node)
9202 return error_mark_node;
9204 if (purpose == TREE_PURPOSE (t)
9205 && value == TREE_VALUE (t)
9206 && chain == TREE_CHAIN (t))
9208 return hash_tree_cons (purpose, value, chain);
9212 /* We should never be tsubsting a binfo. */
9216 /* A vector of template arguments. */
9218 return tsubst_template_args (t, args, complain, in_decl);
9221 case REFERENCE_TYPE:
9223 enum tree_code code;
9225 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
9228 code = TREE_CODE (t);
9233 Type deduction may fail for any of the following
9236 -- Attempting to create a pointer to reference type.
9237 -- Attempting to create a reference to a reference type or
9238 a reference to void.
9240 Core issue 106 says that creating a reference to a reference
9241 during instantiation is no longer a cause for failure. We
9242 only enforce this check in strict C++98 mode. */
9243 if ((TREE_CODE (type) == REFERENCE_TYPE
9244 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
9245 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
9247 static location_t last_loc;
9249 /* We keep track of the last time we issued this error
9250 message to avoid spewing a ton of messages during a
9251 single bad template instantiation. */
9252 if (complain & tf_error
9253 && last_loc != input_location)
9255 if (TREE_CODE (type) == VOID_TYPE)
9256 error ("forming reference to void");
9258 error ("forming %s to reference type %qT",
9259 (code == POINTER_TYPE) ? "pointer" : "reference",
9261 last_loc = input_location;
9264 return error_mark_node;
9266 else if (code == POINTER_TYPE)
9268 r = build_pointer_type (type);
9269 if (TREE_CODE (type) == METHOD_TYPE)
9270 r = build_ptrmemfunc_type (r);
9272 else if (TREE_CODE (type) == REFERENCE_TYPE)
9273 /* In C++0x, during template argument substitution, when there is an
9274 attempt to create a reference to a reference type, reference
9275 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
9277 "If a template-argument for a template-parameter T names a type
9278 that is a reference to a type A, an attempt to create the type
9279 'lvalue reference to cv T' creates the type 'lvalue reference to
9280 A,' while an attempt to create the type type rvalue reference to
9281 cv T' creates the type T"
9283 r = cp_build_reference_type
9285 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
9287 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
9288 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
9290 if (r != error_mark_node)
9291 /* Will this ever be needed for TYPE_..._TO values? */
9298 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
9299 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
9303 Type deduction may fail for any of the following
9306 -- Attempting to create "pointer to member of T" when T
9307 is not a class type. */
9308 if (complain & tf_error)
9309 error ("creating pointer to member of non-class type %qT", r);
9310 return error_mark_node;
9312 if (TREE_CODE (type) == REFERENCE_TYPE)
9314 if (complain & tf_error)
9315 error ("creating pointer to member reference type %qT", type);
9316 return error_mark_node;
9318 if (TREE_CODE (type) == VOID_TYPE)
9320 if (complain & tf_error)
9321 error ("creating pointer to member of type void");
9322 return error_mark_node;
9324 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
9325 if (TREE_CODE (type) == FUNCTION_TYPE)
9327 /* The type of the implicit object parameter gets its
9328 cv-qualifiers from the FUNCTION_TYPE. */
9330 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
9331 cp_type_quals (type));
9333 method_type = build_method_type_directly (this_type,
9335 TYPE_ARG_TYPES (type));
9336 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
9337 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
9341 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
9350 fntype = tsubst_function_type (t, args, complain, in_decl);
9351 if (fntype == error_mark_node)
9352 return error_mark_node;
9354 /* Substitute the exception specification. */
9355 specs = tsubst_exception_specification (t, args, complain,
9357 if (specs == error_mark_node)
9358 return error_mark_node;
9360 fntype = build_exception_variant (fntype, specs);
9365 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
9366 if (domain == error_mark_node)
9367 return error_mark_node;
9369 /* As an optimization, we avoid regenerating the array type if
9370 it will obviously be the same as T. */
9371 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
9374 /* These checks should match the ones in grokdeclarator.
9378 The deduction may fail for any of the following reasons:
9380 -- Attempting to create an array with an element type that
9381 is void, a function type, or a reference type, or [DR337]
9382 an abstract class type. */
9383 if (TREE_CODE (type) == VOID_TYPE
9384 || TREE_CODE (type) == FUNCTION_TYPE
9385 || TREE_CODE (type) == REFERENCE_TYPE)
9387 if (complain & tf_error)
9388 error ("creating array of %qT", type);
9389 return error_mark_node;
9391 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
9393 if (complain & tf_error)
9394 error ("creating array of %qT, which is an abstract class type",
9396 return error_mark_node;
9399 r = build_cplus_array_type (type, domain);
9401 if (TYPE_USER_ALIGN (t))
9403 TYPE_ALIGN (r) = TYPE_ALIGN (t);
9404 TYPE_USER_ALIGN (r) = 1;
9413 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9414 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9416 if (e1 == error_mark_node || e2 == error_mark_node)
9417 return error_mark_node;
9419 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
9425 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9426 if (e == error_mark_node)
9427 return error_mark_node;
9429 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
9434 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9435 in_decl, /*entering_scope=*/1);
9436 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
9439 if (ctx == error_mark_node || f == error_mark_node)
9440 return error_mark_node;
9442 if (!MAYBE_CLASS_TYPE_P (ctx))
9444 if (complain & tf_error)
9445 error ("%qT is not a class, struct, or union type", ctx);
9446 return error_mark_node;
9448 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
9450 /* Normally, make_typename_type does not require that the CTX
9451 have complete type in order to allow things like:
9453 template <class T> struct S { typename S<T>::X Y; };
9455 But, such constructs have already been resolved by this
9456 point, so here CTX really should have complete type, unless
9457 it's a partial instantiation. */
9458 ctx = complete_type (ctx);
9459 if (!COMPLETE_TYPE_P (ctx))
9461 if (complain & tf_error)
9462 cxx_incomplete_type_error (NULL_TREE, ctx);
9463 return error_mark_node;
9467 f = make_typename_type (ctx, f, typename_type,
9468 (complain & tf_error) | tf_keep_type_decl);
9469 if (f == error_mark_node)
9471 if (TREE_CODE (f) == TYPE_DECL)
9473 complain |= tf_ignore_bad_quals;
9477 if (TREE_CODE (f) != TYPENAME_TYPE)
9479 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
9480 error ("%qT resolves to %qT, which is not an enumeration type",
9482 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
9483 error ("%qT resolves to %qT, which is is not a class type",
9487 return cp_build_qualified_type_real
9488 (f, cp_type_quals (f) | cp_type_quals (t), complain);
9491 case UNBOUND_CLASS_TEMPLATE:
9493 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9494 in_decl, /*entering_scope=*/1);
9495 tree name = TYPE_IDENTIFIER (t);
9496 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
9498 if (ctx == error_mark_node || name == error_mark_node)
9499 return error_mark_node;
9502 parm_list = tsubst_template_parms (parm_list, args, complain);
9503 return make_unbound_class_template (ctx, name, parm_list, complain);
9513 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9514 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
9515 /*integral_constant_expression_p=*/false);
9516 if (e1 == error_mark_node || e2 == error_mark_node)
9517 return error_mark_node;
9519 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
9524 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9525 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9526 if (e1 == error_mark_node || e2 == error_mark_node)
9527 return error_mark_node;
9529 return build_qualified_name (/*type=*/NULL_TREE,
9530 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
9537 type = finish_typeof (tsubst_expr
9538 (TYPEOF_TYPE_EXPR (t), args,
9540 /*integral_constant_expression_p=*/false));
9541 return cp_build_qualified_type_real (type,
9543 | cp_type_quals (type),
9552 finish_decltype_type (tsubst_expr
9553 (DECLTYPE_TYPE_EXPR (t), args,
9555 /*integral_constant_expression_p=*/false),
9556 DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
9557 return cp_build_qualified_type_real (type,
9559 | cp_type_quals (type),
9563 case TYPE_ARGUMENT_PACK:
9564 case NONTYPE_ARGUMENT_PACK:
9566 tree r = make_node (TREE_CODE (t));
9568 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
9572 SET_ARGUMENT_PACK_ARGS (r, packed_out);
9574 /* For template nontype argument packs, also substitute into
9576 if (TREE_CODE (t) == NONTYPE_ARGUMENT_PACK)
9577 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
9584 sorry ("use of %qs in template",
9585 tree_code_name [(int) TREE_CODE (t)]);
9586 return error_mark_node;
9590 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
9591 type of the expression on the left-hand side of the "." or "->"
9595 tsubst_baselink (tree baselink, tree object_type,
9596 tree args, tsubst_flags_t complain, tree in_decl)
9599 tree qualifying_scope;
9602 tree template_args = 0;
9603 bool template_id_p = false;
9605 /* A baselink indicates a function from a base class. Both the
9606 BASELINK_ACCESS_BINFO and the base class referenced may
9607 indicate bases of the template class, rather than the
9608 instantiated class. In addition, lookups that were not
9609 ambiguous before may be ambiguous now. Therefore, we perform
9610 the lookup again. */
9611 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
9612 qualifying_scope = tsubst (qualifying_scope, args,
9614 fns = BASELINK_FUNCTIONS (baselink);
9615 optype = BASELINK_OPTYPE (baselink);
9616 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
9618 template_id_p = true;
9619 template_args = TREE_OPERAND (fns, 1);
9620 fns = TREE_OPERAND (fns, 0);
9622 template_args = tsubst_template_args (template_args, args,
9625 name = DECL_NAME (get_first_fn (fns));
9626 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
9628 /* If lookup found a single function, mark it as used at this
9629 point. (If it lookup found multiple functions the one selected
9630 later by overload resolution will be marked as used at that
9632 if (BASELINK_P (baselink))
9633 fns = BASELINK_FUNCTIONS (baselink);
9634 if (!template_id_p && !really_overloaded_fn (fns))
9635 mark_used (OVL_CURRENT (fns));
9637 /* Add back the template arguments, if present. */
9638 if (BASELINK_P (baselink) && template_id_p)
9639 BASELINK_FUNCTIONS (baselink)
9640 = build_nt (TEMPLATE_ID_EXPR,
9641 BASELINK_FUNCTIONS (baselink),
9643 /* Update the conversion operator type. */
9644 BASELINK_OPTYPE (baselink)
9645 = tsubst (optype, args, complain, in_decl);
9648 object_type = current_class_type;
9649 return adjust_result_of_qualified_name_lookup (baselink,
9654 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
9655 true if the qualified-id will be a postfix-expression in-and-of
9656 itself; false if more of the postfix-expression follows the
9657 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
9661 tsubst_qualified_id (tree qualified_id, tree args,
9662 tsubst_flags_t complain, tree in_decl,
9663 bool done, bool address_p)
9671 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
9673 /* Figure out what name to look up. */
9674 name = TREE_OPERAND (qualified_id, 1);
9675 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
9678 template_args = TREE_OPERAND (name, 1);
9680 template_args = tsubst_template_args (template_args, args,
9682 name = TREE_OPERAND (name, 0);
9686 is_template = false;
9687 template_args = NULL_TREE;
9690 /* Substitute into the qualifying scope. When there are no ARGS, we
9691 are just trying to simplify a non-dependent expression. In that
9692 case the qualifying scope may be dependent, and, in any case,
9693 substituting will not help. */
9694 scope = TREE_OPERAND (qualified_id, 0);
9697 scope = tsubst (scope, args, complain, in_decl);
9698 expr = tsubst_copy (name, args, complain, in_decl);
9703 if (dependent_type_p (scope))
9704 return build_qualified_name (/*type=*/NULL_TREE,
9706 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
9708 if (!BASELINK_P (name) && !DECL_P (expr))
9710 if (TREE_CODE (expr) == BIT_NOT_EXPR)
9711 /* If this were actually a destructor call, it would have been
9712 parsed as such by the parser. */
9713 expr = error_mark_node;
9715 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
9716 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
9717 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
9719 if (complain & tf_error)
9721 error ("dependent-name %qE is parsed as a non-type, but "
9722 "instantiation yields a type", qualified_id);
9723 inform ("say %<typename %E%> if a type is meant", qualified_id);
9725 return error_mark_node;
9731 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
9733 /* Remember that there was a reference to this entity. */
9737 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
9739 if (complain & tf_error)
9740 qualified_name_lookup_error (scope,
9741 TREE_OPERAND (qualified_id, 1),
9742 expr, input_location);
9743 return error_mark_node;
9747 expr = lookup_template_function (expr, template_args);
9749 if (expr == error_mark_node && complain & tf_error)
9750 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
9751 expr, input_location);
9752 else if (TYPE_P (scope))
9754 expr = (adjust_result_of_qualified_name_lookup
9755 (expr, scope, current_class_type));
9756 expr = (finish_qualified_id_expr
9757 (scope, expr, done, address_p,
9758 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
9759 /*template_arg_p=*/false));
9762 /* Expressions do not generally have reference type. */
9763 if (TREE_CODE (expr) != SCOPE_REF
9764 /* However, if we're about to form a pointer-to-member, we just
9765 want the referenced member referenced. */
9766 && TREE_CODE (expr) != OFFSET_REF)
9767 expr = convert_from_reference (expr);
9772 /* Like tsubst, but deals with expressions. This function just replaces
9773 template parms; to finish processing the resultant expression, use
9777 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9779 enum tree_code code;
9782 if (t == NULL_TREE || t == error_mark_node)
9785 code = TREE_CODE (t);
9790 r = retrieve_local_specialization (t);
9791 gcc_assert (r != NULL);
9792 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
9793 r = ARGUMENT_PACK_SELECT_ARG (r);
9802 if (DECL_TEMPLATE_PARM_P (t))
9803 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
9804 /* There is no need to substitute into namespace-scope
9806 if (DECL_NAMESPACE_SCOPE_P (t))
9808 /* If ARGS is NULL, then T is known to be non-dependent. */
9809 if (args == NULL_TREE)
9810 return integral_constant_value (t);
9812 /* Unfortunately, we cannot just call lookup_name here.
9815 template <int I> int f() {
9817 struct S { void g() { E e = a; } };
9820 When we instantiate f<7>::S::g(), say, lookup_name is not
9821 clever enough to find f<7>::a. */
9823 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
9824 /*entering_scope=*/0);
9826 for (v = TYPE_VALUES (enum_type);
9829 if (TREE_PURPOSE (v) == DECL_NAME (t))
9830 return TREE_VALUE (v);
9832 /* We didn't find the name. That should never happen; if
9833 name-lookup found it during preliminary parsing, we
9834 should find it again here during instantiation. */
9840 if (DECL_CONTEXT (t))
9844 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
9845 /*entering_scope=*/1);
9846 if (ctx != DECL_CONTEXT (t))
9848 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
9851 if (complain & tf_error)
9852 error ("using invalid field %qD", t);
9853 return error_mark_node;
9863 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
9864 || local_variable_p (t))
9865 t = tsubst (t, args, complain, in_decl);
9870 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
9873 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9874 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
9875 args, complain, in_decl);
9876 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
9877 return tsubst (t, args, complain, in_decl);
9878 else if (DECL_CLASS_SCOPE_P (t)
9879 && uses_template_parms (DECL_CONTEXT (t)))
9881 /* Template template argument like the following example need
9884 template <template <class> class TT> struct C {};
9885 template <class T> struct D {
9886 template <class U> struct E {};
9891 We are processing the template argument `E' in #1 for
9892 the template instantiation #2. Originally, `E' is a
9893 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
9894 have to substitute this with one having context `D<int>'. */
9896 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
9897 return lookup_field (context, DECL_NAME(t), 0, false);
9900 /* Ordinary template template argument. */
9904 case REINTERPRET_CAST_EXPR:
9905 case CONST_CAST_EXPR:
9906 case STATIC_CAST_EXPR:
9907 case DYNAMIC_CAST_EXPR:
9910 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
9911 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
9914 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
9916 /* We only want to compute the number of arguments. */
9917 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
9921 if (TREE_CODE (expanded) == TREE_VEC)
9922 len = TREE_VEC_LENGTH (expanded);
9924 if (expanded == error_mark_node)
9925 return error_mark_node;
9926 else if (PACK_EXPANSION_P (expanded)
9927 || (TREE_CODE (expanded) == TREE_VEC
9929 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
9931 if (TREE_CODE (expanded) == TREE_VEC)
9932 expanded = TREE_VEC_ELT (expanded, len - 1);
9934 if (TYPE_P (expanded))
9935 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
9936 complain & tf_error);
9938 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
9939 complain & tf_error);
9942 return build_int_cst (size_type_node, len);
9948 case TRUTH_NOT_EXPR:
9951 case UNARY_PLUS_EXPR: /* Unary + */
9959 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
9960 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
9967 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
9968 name = TREE_OPERAND (t, 1);
9969 if (TREE_CODE (name) == BIT_NOT_EXPR)
9971 name = tsubst_copy (TREE_OPERAND (name, 0), args,
9973 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
9975 else if (TREE_CODE (name) == SCOPE_REF
9976 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
9978 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
9980 name = TREE_OPERAND (name, 1);
9981 name = tsubst_copy (TREE_OPERAND (name, 0), args,
9983 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
9984 name = build_qualified_name (/*type=*/NULL_TREE,
9986 /*template_p=*/false);
9988 else if (TREE_CODE (name) == BASELINK)
9989 name = tsubst_baselink (name,
9990 non_reference (TREE_TYPE (object)),
9994 name = tsubst_copy (name, args, complain, in_decl);
9995 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
10001 case TRUNC_DIV_EXPR:
10002 case CEIL_DIV_EXPR:
10003 case FLOOR_DIV_EXPR:
10004 case ROUND_DIV_EXPR:
10005 case EXACT_DIV_EXPR:
10009 case TRUNC_MOD_EXPR:
10010 case FLOOR_MOD_EXPR:
10011 case TRUTH_ANDIF_EXPR:
10012 case TRUTH_ORIF_EXPR:
10013 case TRUTH_AND_EXPR:
10014 case TRUTH_OR_EXPR:
10027 case COMPOUND_EXPR:
10030 case PREDECREMENT_EXPR:
10031 case PREINCREMENT_EXPR:
10032 case POSTDECREMENT_EXPR:
10033 case POSTINCREMENT_EXPR:
10035 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10036 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10039 return build_qualified_name (/*type=*/NULL_TREE,
10040 tsubst_copy (TREE_OPERAND (t, 0),
10041 args, complain, in_decl),
10042 tsubst_copy (TREE_OPERAND (t, 1),
10043 args, complain, in_decl),
10044 QUALIFIED_NAME_IS_TEMPLATE (t));
10049 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10050 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10051 NULL_TREE, NULL_TREE);
10055 int n = VL_EXP_OPERAND_LENGTH (t);
10056 tree result = build_vl_exp (CALL_EXPR, n);
10058 for (i = 0; i < n; i++)
10059 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
10060 complain, in_decl);
10066 case PSEUDO_DTOR_EXPR:
10069 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10070 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10071 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10072 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
10079 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10080 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10081 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10082 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
10089 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10090 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10091 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
10092 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
10096 case TEMPLATE_ID_EXPR:
10098 /* Substituted template arguments */
10099 tree fn = TREE_OPERAND (t, 0);
10100 tree targs = TREE_OPERAND (t, 1);
10102 fn = tsubst_copy (fn, args, complain, in_decl);
10104 targs = tsubst_template_args (targs, args, complain, in_decl);
10106 return lookup_template_function (fn, targs);
10111 tree purpose, value, chain;
10113 if (t == void_list_node)
10116 purpose = TREE_PURPOSE (t);
10118 purpose = tsubst_copy (purpose, args, complain, in_decl);
10119 value = TREE_VALUE (t);
10121 value = tsubst_copy (value, args, complain, in_decl);
10122 chain = TREE_CHAIN (t);
10123 if (chain && chain != void_type_node)
10124 chain = tsubst_copy (chain, args, complain, in_decl);
10125 if (purpose == TREE_PURPOSE (t)
10126 && value == TREE_VALUE (t)
10127 && chain == TREE_CHAIN (t))
10129 return tree_cons (purpose, value, chain);
10134 case ENUMERAL_TYPE:
10136 case TEMPLATE_TYPE_PARM:
10137 case TEMPLATE_TEMPLATE_PARM:
10138 case BOUND_TEMPLATE_TEMPLATE_PARM:
10139 case TEMPLATE_PARM_INDEX:
10141 case REFERENCE_TYPE:
10143 case FUNCTION_TYPE:
10146 case TYPENAME_TYPE:
10147 case UNBOUND_CLASS_TEMPLATE:
10149 case DECLTYPE_TYPE:
10151 return tsubst (t, args, complain, in_decl);
10153 case IDENTIFIER_NODE:
10154 if (IDENTIFIER_TYPENAME_P (t))
10156 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10157 return mangle_conv_op_name_for_type (new_type);
10163 /* This is handled by tsubst_copy_and_build. */
10164 gcc_unreachable ();
10167 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
10169 tsubst (TREE_TYPE (t), args, complain, in_decl));
10171 case CLEANUP_POINT_EXPR:
10172 /* We shouldn't have built any of these during initial template
10173 generation. Instead, they should be built during instantiation
10174 in response to the saved STMT_IS_FULL_EXPR_P setting. */
10175 gcc_unreachable ();
10178 mark_used (TREE_OPERAND (t, 1));
10181 case EXPR_PACK_EXPANSION:
10182 error ("invalid use of pack expansion expression");
10183 return error_mark_node;
10185 case NONTYPE_ARGUMENT_PACK:
10186 error ("use %<...%> to expand argument pack");
10187 return error_mark_node;
10194 /* Like tsubst_copy, but specifically for OpenMP clauses. */
10197 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
10200 tree new_clauses = NULL, nc, oc;
10202 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
10204 nc = copy_node (oc);
10205 OMP_CLAUSE_CHAIN (nc) = new_clauses;
10208 switch (OMP_CLAUSE_CODE (nc))
10210 case OMP_CLAUSE_LASTPRIVATE:
10211 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
10213 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
10214 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
10215 in_decl, /*integral_constant_expression_p=*/false);
10216 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
10217 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
10220 case OMP_CLAUSE_PRIVATE:
10221 case OMP_CLAUSE_SHARED:
10222 case OMP_CLAUSE_FIRSTPRIVATE:
10223 case OMP_CLAUSE_REDUCTION:
10224 case OMP_CLAUSE_COPYIN:
10225 case OMP_CLAUSE_COPYPRIVATE:
10226 case OMP_CLAUSE_IF:
10227 case OMP_CLAUSE_NUM_THREADS:
10228 case OMP_CLAUSE_SCHEDULE:
10229 case OMP_CLAUSE_COLLAPSE:
10230 OMP_CLAUSE_OPERAND (nc, 0)
10231 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
10232 in_decl, /*integral_constant_expression_p=*/false);
10234 case OMP_CLAUSE_NOWAIT:
10235 case OMP_CLAUSE_ORDERED:
10236 case OMP_CLAUSE_DEFAULT:
10237 case OMP_CLAUSE_UNTIED:
10240 gcc_unreachable ();
10244 return finish_omp_clauses (nreverse (new_clauses));
10247 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
10250 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
10253 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
10255 tree purpose, value, chain;
10260 if (TREE_CODE (t) != TREE_LIST)
10261 return tsubst_copy_and_build (t, args, complain, in_decl,
10262 /*function_p=*/false,
10263 /*integral_constant_expression_p=*/false);
10265 if (t == void_list_node)
10268 purpose = TREE_PURPOSE (t);
10270 purpose = RECUR (purpose);
10271 value = TREE_VALUE (t);
10273 value = RECUR (value);
10274 chain = TREE_CHAIN (t);
10275 if (chain && chain != void_type_node)
10276 chain = RECUR (chain);
10277 return tree_cons (purpose, value, chain);
10281 /* Substitute one OMP_FOR iterator. */
10284 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
10285 tree condv, tree incrv, tree *clauses,
10286 tree args, tsubst_flags_t complain, tree in_decl,
10287 bool integral_constant_expression_p)
10289 #define RECUR(NODE) \
10290 tsubst_expr ((NODE), args, complain, in_decl, \
10291 integral_constant_expression_p)
10292 tree decl, init, cond, incr;
10294 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
10295 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
10296 decl = RECUR (TREE_OPERAND (init, 0));
10297 init = TREE_OPERAND (init, 1);
10298 gcc_assert (!type_dependent_expression_p (decl));
10300 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
10302 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
10303 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
10304 if (TREE_CODE (incr) == MODIFY_EXPR)
10305 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
10306 RECUR (TREE_OPERAND (incr, 1)),
10309 incr = RECUR (incr);
10310 TREE_VEC_ELT (declv, i) = decl;
10311 TREE_VEC_ELT (initv, i) = init;
10312 TREE_VEC_ELT (condv, i) = cond;
10313 TREE_VEC_ELT (incrv, i) = incr;
10317 if (init && TREE_CODE (init) != DECL_EXPR)
10320 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
10322 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
10323 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
10324 && OMP_CLAUSE_DECL (c) == decl)
10326 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
10327 && OMP_CLAUSE_DECL (c) == decl)
10328 error ("iteration variable %qD should not be firstprivate", decl);
10329 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
10330 && OMP_CLAUSE_DECL (c) == decl)
10331 error ("iteration variable %qD should not be reduction", decl);
10335 c = build_omp_clause (OMP_CLAUSE_PRIVATE);
10336 OMP_CLAUSE_DECL (c) = decl;
10337 c = finish_omp_clauses (c);
10340 OMP_CLAUSE_CHAIN (c) = *clauses;
10345 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
10346 if (COMPARISON_CLASS_P (cond))
10347 cond = build2 (TREE_CODE (cond), boolean_type_node,
10348 RECUR (TREE_OPERAND (cond, 0)),
10349 RECUR (TREE_OPERAND (cond, 1)));
10351 cond = RECUR (cond);
10352 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
10353 switch (TREE_CODE (incr))
10355 case PREINCREMENT_EXPR:
10356 case PREDECREMENT_EXPR:
10357 case POSTINCREMENT_EXPR:
10358 case POSTDECREMENT_EXPR:
10359 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
10360 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
10363 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
10364 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
10366 tree rhs = TREE_OPERAND (incr, 1);
10367 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
10368 RECUR (TREE_OPERAND (incr, 0)),
10369 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
10370 RECUR (TREE_OPERAND (rhs, 0)),
10371 RECUR (TREE_OPERAND (rhs, 1))));
10374 incr = RECUR (incr);
10377 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
10378 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
10380 tree lhs = RECUR (TREE_OPERAND (incr, 0));
10381 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
10382 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
10383 TREE_TYPE (decl), lhs,
10384 RECUR (TREE_OPERAND (incr, 2))));
10386 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
10387 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
10388 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
10390 tree rhs = TREE_OPERAND (incr, 2);
10391 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
10392 RECUR (TREE_OPERAND (incr, 0)),
10393 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
10394 RECUR (TREE_OPERAND (rhs, 0)),
10395 RECUR (TREE_OPERAND (rhs, 1))));
10398 incr = RECUR (incr);
10401 incr = RECUR (incr);
10405 TREE_VEC_ELT (declv, i) = decl;
10406 TREE_VEC_ELT (initv, i) = init;
10407 TREE_VEC_ELT (condv, i) = cond;
10408 TREE_VEC_ELT (incrv, i) = incr;
10412 /* Like tsubst_copy for expressions, etc. but also does semantic
10416 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
10417 bool integral_constant_expression_p)
10419 #define RECUR(NODE) \
10420 tsubst_expr ((NODE), args, complain, in_decl, \
10421 integral_constant_expression_p)
10425 if (t == NULL_TREE || t == error_mark_node)
10428 if (EXPR_HAS_LOCATION (t))
10429 input_location = EXPR_LOCATION (t);
10430 if (STATEMENT_CODE_P (TREE_CODE (t)))
10431 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
10433 switch (TREE_CODE (t))
10435 case STATEMENT_LIST:
10437 tree_stmt_iterator i;
10438 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
10439 RECUR (tsi_stmt (i));
10443 case CTOR_INITIALIZER:
10444 finish_mem_initializers (tsubst_initializer_list
10445 (TREE_OPERAND (t, 0), args));
10449 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
10453 tmp = RECUR (EXPR_STMT_EXPR (t));
10454 if (EXPR_STMT_STMT_EXPR_RESULT (t))
10455 finish_stmt_expr_expr (tmp, cur_stmt_expr);
10457 finish_expr_stmt (tmp);
10461 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
10469 decl = DECL_EXPR_DECL (t);
10470 if (TREE_CODE (decl) == LABEL_DECL)
10471 finish_label_decl (DECL_NAME (decl));
10472 else if (TREE_CODE (decl) == USING_DECL)
10474 tree scope = USING_DECL_SCOPE (decl);
10475 tree name = DECL_NAME (decl);
10478 scope = RECUR (scope);
10479 decl = lookup_qualified_name (scope, name,
10480 /*is_type_p=*/false,
10481 /*complain=*/false);
10482 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
10483 qualified_name_lookup_error (scope, name, decl, input_location);
10485 do_local_using_decl (decl, scope, name);
10489 init = DECL_INITIAL (decl);
10490 decl = tsubst (decl, args, complain, in_decl);
10491 if (decl != error_mark_node)
10493 /* By marking the declaration as instantiated, we avoid
10494 trying to instantiate it. Since instantiate_decl can't
10495 handle local variables, and since we've already done
10496 all that needs to be done, that's the right thing to
10498 if (TREE_CODE (decl) == VAR_DECL)
10499 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
10500 if (TREE_CODE (decl) == VAR_DECL
10501 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
10502 /* Anonymous aggregates are a special case. */
10503 finish_anon_union (decl);
10506 maybe_push_decl (decl);
10507 if (TREE_CODE (decl) == VAR_DECL
10508 && DECL_PRETTY_FUNCTION_P (decl))
10510 /* For __PRETTY_FUNCTION__ we have to adjust the
10512 const char *const name
10513 = cxx_printable_name (current_function_decl, 2);
10514 init = cp_fname_init (name, &TREE_TYPE (decl));
10518 tree t = RECUR (init);
10521 /* If we had an initializer but it
10522 instantiated to nothing,
10523 value-initialize the object. This will
10524 only occur when the initializer was a
10525 pack expansion where the parameter packs
10526 used in that expansion were of length
10528 init = build_default_init (TREE_TYPE (decl),
10534 finish_decl (decl, init, NULL_TREE);
10539 /* A DECL_EXPR can also be used as an expression, in the condition
10540 clause of an if/for/while construct. */
10545 stmt = begin_for_stmt ();
10546 RECUR (FOR_INIT_STMT (t));
10547 finish_for_init_stmt (stmt);
10548 tmp = RECUR (FOR_COND (t));
10549 finish_for_cond (tmp, stmt);
10550 tmp = RECUR (FOR_EXPR (t));
10551 finish_for_expr (tmp, stmt);
10552 RECUR (FOR_BODY (t));
10553 finish_for_stmt (stmt);
10557 stmt = begin_while_stmt ();
10558 tmp = RECUR (WHILE_COND (t));
10559 finish_while_stmt_cond (tmp, stmt);
10560 RECUR (WHILE_BODY (t));
10561 finish_while_stmt (stmt);
10565 stmt = begin_do_stmt ();
10566 RECUR (DO_BODY (t));
10567 finish_do_body (stmt);
10568 tmp = RECUR (DO_COND (t));
10569 finish_do_stmt (tmp, stmt);
10573 stmt = begin_if_stmt ();
10574 tmp = RECUR (IF_COND (t));
10575 finish_if_stmt_cond (tmp, stmt);
10576 RECUR (THEN_CLAUSE (t));
10577 finish_then_clause (stmt);
10579 if (ELSE_CLAUSE (t))
10581 begin_else_clause (stmt);
10582 RECUR (ELSE_CLAUSE (t));
10583 finish_else_clause (stmt);
10586 finish_if_stmt (stmt);
10590 if (BIND_EXPR_BODY_BLOCK (t))
10591 stmt = begin_function_body ();
10593 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
10594 ? BCS_TRY_BLOCK : 0);
10596 RECUR (BIND_EXPR_BODY (t));
10598 if (BIND_EXPR_BODY_BLOCK (t))
10599 finish_function_body (stmt);
10601 finish_compound_stmt (stmt);
10605 finish_break_stmt ();
10608 case CONTINUE_STMT:
10609 finish_continue_stmt ();
10613 stmt = begin_switch_stmt ();
10614 tmp = RECUR (SWITCH_STMT_COND (t));
10615 finish_switch_cond (tmp, stmt);
10616 RECUR (SWITCH_STMT_BODY (t));
10617 finish_switch_stmt (stmt);
10620 case CASE_LABEL_EXPR:
10621 finish_case_label (RECUR (CASE_LOW (t)),
10622 RECUR (CASE_HIGH (t)));
10626 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
10630 tmp = GOTO_DESTINATION (t);
10631 if (TREE_CODE (tmp) != LABEL_DECL)
10632 /* Computed goto's must be tsubst'd into. On the other hand,
10633 non-computed gotos must not be; the identifier in question
10634 will have no binding. */
10637 tmp = DECL_NAME (tmp);
10638 finish_goto_stmt (tmp);
10642 tmp = finish_asm_stmt
10643 (ASM_VOLATILE_P (t),
10644 RECUR (ASM_STRING (t)),
10645 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
10646 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
10647 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl));
10649 tree asm_expr = tmp;
10650 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
10651 asm_expr = TREE_OPERAND (asm_expr, 0);
10652 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
10659 stmt = begin_try_block ();
10660 RECUR (TRY_STMTS (t));
10661 finish_cleanup_try_block (stmt);
10662 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
10666 tree compound_stmt = NULL_TREE;
10668 if (FN_TRY_BLOCK_P (t))
10669 stmt = begin_function_try_block (&compound_stmt);
10671 stmt = begin_try_block ();
10673 RECUR (TRY_STMTS (t));
10675 if (FN_TRY_BLOCK_P (t))
10676 finish_function_try_block (stmt);
10678 finish_try_block (stmt);
10680 RECUR (TRY_HANDLERS (t));
10681 if (FN_TRY_BLOCK_P (t))
10682 finish_function_handler_sequence (stmt, compound_stmt);
10684 finish_handler_sequence (stmt);
10690 tree decl = HANDLER_PARMS (t);
10694 decl = tsubst (decl, args, complain, in_decl);
10695 /* Prevent instantiate_decl from trying to instantiate
10696 this variable. We've already done all that needs to be
10698 if (decl != error_mark_node)
10699 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
10701 stmt = begin_handler ();
10702 finish_handler_parms (decl, stmt);
10703 RECUR (HANDLER_BODY (t));
10704 finish_handler (stmt);
10709 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
10712 case STATIC_ASSERT:
10715 tsubst_expr (STATIC_ASSERT_CONDITION (t),
10718 /*integral_constant_expression_p=*/true);
10719 finish_static_assert (condition,
10720 STATIC_ASSERT_MESSAGE (t),
10721 STATIC_ASSERT_SOURCE_LOCATION (t),
10722 /*member_p=*/false);
10727 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
10728 args, complain, in_decl);
10729 stmt = begin_omp_parallel ();
10730 RECUR (OMP_PARALLEL_BODY (t));
10731 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
10732 = OMP_PARALLEL_COMBINED (t);
10736 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
10737 args, complain, in_decl);
10738 stmt = begin_omp_task ();
10739 RECUR (OMP_TASK_BODY (t));
10740 finish_omp_task (tmp, stmt);
10745 tree clauses, body, pre_body;
10746 tree declv, initv, condv, incrv;
10749 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
10750 args, complain, in_decl);
10751 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
10752 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
10753 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
10754 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
10756 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
10757 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
10758 &clauses, args, complain, in_decl,
10759 integral_constant_expression_p);
10761 stmt = begin_omp_structured_block ();
10763 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
10764 if (TREE_VEC_ELT (initv, i) == NULL
10765 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
10766 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
10767 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
10769 tree init = RECUR (TREE_VEC_ELT (initv, i));
10770 gcc_assert (init == TREE_VEC_ELT (declv, i));
10771 TREE_VEC_ELT (initv, i) = NULL_TREE;
10775 tree decl_expr = TREE_VEC_ELT (initv, i);
10776 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
10777 gcc_assert (init != NULL);
10778 TREE_VEC_ELT (initv, i) = RECUR (init);
10779 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
10781 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
10784 pre_body = push_stmt_list ();
10785 RECUR (OMP_FOR_PRE_BODY (t));
10786 pre_body = pop_stmt_list (pre_body);
10788 body = push_stmt_list ();
10789 RECUR (OMP_FOR_BODY (t));
10790 body = pop_stmt_list (body);
10792 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
10793 body, pre_body, clauses);
10795 add_stmt (finish_omp_structured_block (stmt));
10801 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
10802 stmt = push_stmt_list ();
10803 RECUR (OMP_BODY (t));
10804 stmt = pop_stmt_list (stmt);
10807 OMP_BODY (t) = stmt;
10808 OMP_CLAUSES (t) = tmp;
10816 stmt = push_stmt_list ();
10817 RECUR (OMP_BODY (t));
10818 stmt = pop_stmt_list (stmt);
10821 OMP_BODY (t) = stmt;
10826 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
10828 tree op1 = TREE_OPERAND (t, 1);
10829 tree lhs = RECUR (TREE_OPERAND (op1, 0));
10830 tree rhs = RECUR (TREE_OPERAND (op1, 1));
10831 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
10835 case EXPR_PACK_EXPANSION:
10836 error ("invalid use of pack expansion expression");
10837 return error_mark_node;
10839 case NONTYPE_ARGUMENT_PACK:
10840 error ("use %<...%> to expand argument pack");
10841 return error_mark_node;
10844 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
10846 return tsubst_copy_and_build (t, args, complain, in_decl,
10847 /*function_p=*/false,
10848 integral_constant_expression_p);
10855 /* T is a postfix-expression that is not being used in a function
10856 call. Return the substituted version of T. */
10859 tsubst_non_call_postfix_expression (tree t, tree args,
10860 tsubst_flags_t complain,
10863 if (TREE_CODE (t) == SCOPE_REF)
10864 t = tsubst_qualified_id (t, args, complain, in_decl,
10865 /*done=*/false, /*address_p=*/false);
10867 t = tsubst_copy_and_build (t, args, complain, in_decl,
10868 /*function_p=*/false,
10869 /*integral_constant_expression_p=*/false);
10874 /* Like tsubst but deals with expressions and performs semantic
10875 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
10878 tsubst_copy_and_build (tree t,
10880 tsubst_flags_t complain,
10883 bool integral_constant_expression_p)
10885 #define RECUR(NODE) \
10886 tsubst_copy_and_build (NODE, args, complain, in_decl, \
10887 /*function_p=*/false, \
10888 integral_constant_expression_p)
10892 if (t == NULL_TREE || t == error_mark_node)
10895 switch (TREE_CODE (t))
10899 /* Fall through. */
10900 case IDENTIFIER_NODE:
10904 bool non_integral_constant_expression_p;
10905 const char *error_msg;
10907 if (IDENTIFIER_TYPENAME_P (t))
10909 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10910 t = mangle_conv_op_name_for_type (new_type);
10913 /* Look up the name. */
10914 decl = lookup_name (t);
10916 /* By convention, expressions use ERROR_MARK_NODE to indicate
10917 failure, not NULL_TREE. */
10918 if (decl == NULL_TREE)
10919 decl = error_mark_node;
10921 decl = finish_id_expression (t, decl, NULL_TREE,
10923 integral_constant_expression_p,
10924 /*allow_non_integral_constant_expression_p=*/false,
10925 &non_integral_constant_expression_p,
10926 /*template_p=*/false,
10928 /*address_p=*/false,
10929 /*template_arg_p=*/false,
10934 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
10935 decl = unqualified_name_lookup_error (decl);
10939 case TEMPLATE_ID_EXPR:
10942 tree templ = RECUR (TREE_OPERAND (t, 0));
10943 tree targs = TREE_OPERAND (t, 1);
10946 targs = tsubst_template_args (targs, args, complain, in_decl);
10948 if (TREE_CODE (templ) == COMPONENT_REF)
10950 object = TREE_OPERAND (templ, 0);
10951 templ = TREE_OPERAND (templ, 1);
10954 object = NULL_TREE;
10955 templ = lookup_template_function (templ, targs);
10958 return build3 (COMPONENT_REF, TREE_TYPE (templ),
10959 object, templ, NULL_TREE);
10961 return baselink_for_fns (templ);
10966 tree r = RECUR (TREE_OPERAND (t, 0));
10968 if (REFERENCE_REF_P (t))
10970 /* A type conversion to reference type will be enclosed in
10971 such an indirect ref, but the substitution of the cast
10972 will have also added such an indirect ref. */
10973 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
10974 r = convert_from_reference (r);
10977 r = build_x_indirect_ref (r, "unary *", complain);
10983 (tsubst (TREE_TYPE (t), args, complain, in_decl),
10984 RECUR (TREE_OPERAND (t, 0)));
10987 case REINTERPRET_CAST_EXPR:
10988 case CONST_CAST_EXPR:
10989 case DYNAMIC_CAST_EXPR:
10990 case STATIC_CAST_EXPR:
10995 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10996 if (integral_constant_expression_p
10997 && !cast_valid_in_integral_constant_expression_p (type))
10999 if (complain & tf_error)
11000 error ("a cast to a type other than an integral or "
11001 "enumeration type cannot appear in a constant-expression");
11002 return error_mark_node;
11005 op = RECUR (TREE_OPERAND (t, 0));
11007 switch (TREE_CODE (t))
11010 return build_functional_cast (type, op, complain);
11011 case REINTERPRET_CAST_EXPR:
11012 return build_reinterpret_cast (type, op, complain);
11013 case CONST_CAST_EXPR:
11014 return build_const_cast (type, op, complain);
11015 case DYNAMIC_CAST_EXPR:
11016 return build_dynamic_cast (type, op, complain);
11017 case STATIC_CAST_EXPR:
11018 return build_static_cast (type, op, complain);
11020 gcc_unreachable ();
11024 case POSTDECREMENT_EXPR:
11025 case POSTINCREMENT_EXPR:
11026 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11027 args, complain, in_decl);
11028 return build_x_unary_op (TREE_CODE (t), op1, complain);
11030 case PREDECREMENT_EXPR:
11031 case PREINCREMENT_EXPR:
11035 case TRUTH_NOT_EXPR:
11036 case UNARY_PLUS_EXPR: /* Unary + */
11037 case REALPART_EXPR:
11038 case IMAGPART_EXPR:
11039 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
11043 op1 = TREE_OPERAND (t, 0);
11044 if (TREE_CODE (op1) == SCOPE_REF)
11045 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
11046 /*done=*/true, /*address_p=*/true);
11048 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
11050 if (TREE_CODE (op1) == LABEL_DECL)
11051 return finish_label_address_expr (DECL_NAME (op1));
11052 return build_x_unary_op (ADDR_EXPR, op1, complain);
11057 case TRUNC_DIV_EXPR:
11058 case CEIL_DIV_EXPR:
11059 case FLOOR_DIV_EXPR:
11060 case ROUND_DIV_EXPR:
11061 case EXACT_DIV_EXPR:
11065 case TRUNC_MOD_EXPR:
11066 case FLOOR_MOD_EXPR:
11067 case TRUTH_ANDIF_EXPR:
11068 case TRUTH_ORIF_EXPR:
11069 case TRUTH_AND_EXPR:
11070 case TRUTH_OR_EXPR:
11085 return build_x_binary_op
11087 RECUR (TREE_OPERAND (t, 0)),
11088 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
11090 : TREE_CODE (TREE_OPERAND (t, 0))),
11091 RECUR (TREE_OPERAND (t, 1)),
11092 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
11094 : TREE_CODE (TREE_OPERAND (t, 1))),
11095 /*overloaded_p=*/NULL,
11099 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
11100 /*address_p=*/false);
11102 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11103 args, complain, in_decl);
11104 return build_x_binary_op (ARRAY_REF, op1,
11105 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
11107 : TREE_CODE (TREE_OPERAND (t, 0))),
11108 RECUR (TREE_OPERAND (t, 1)),
11109 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
11111 : TREE_CODE (TREE_OPERAND (t, 1))),
11112 /*overloaded_p=*/NULL,
11116 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11117 return tsubst_copy (t, args, complain, in_decl);
11121 op1 = TREE_OPERAND (t, 0);
11124 /* When there are no ARGS, we are trying to evaluate a
11125 non-dependent expression from the parser. Trying to do
11126 the substitutions may not work. */
11128 op1 = TREE_TYPE (op1);
11133 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
11134 /*function_p=*/false,
11135 /*integral_constant_expression_p=*/false);
11139 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
11140 complain & tf_error);
11142 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
11143 complain & tf_error);
11147 tree r = build_x_modify_expr
11148 (RECUR (TREE_OPERAND (t, 0)),
11149 TREE_CODE (TREE_OPERAND (t, 1)),
11150 RECUR (TREE_OPERAND (t, 2)),
11152 /* TREE_NO_WARNING must be set if either the expression was
11153 parenthesized or it uses an operator such as >>= rather
11154 than plain assignment. In the former case, it was already
11155 set and must be copied. In the latter case,
11156 build_x_modify_expr sets it and it must not be reset
11158 if (TREE_NO_WARNING (t))
11159 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11164 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11165 args, complain, in_decl);
11166 /* Remember that there was a reference to this entity. */
11169 return build_x_arrow (op1);
11173 tree init = RECUR (TREE_OPERAND (t, 3));
11175 if (TREE_OPERAND (t, 3) && !init)
11176 /* If there was an initializer in the original tree, but
11177 it instantiated to an empty list, then we should pass on
11178 VOID_ZERO_NODE to tell build_new that it was an empty
11179 initializer () rather than no initializer. This can only
11180 happen when the initializer is a pack expansion whose
11181 parameter packs are of length zero. */
11182 init = void_zero_node;
11185 (RECUR (TREE_OPERAND (t, 0)),
11186 RECUR (TREE_OPERAND (t, 1)),
11187 RECUR (TREE_OPERAND (t, 2)),
11189 NEW_EXPR_USE_GLOBAL (t),
11194 return delete_sanity
11195 (RECUR (TREE_OPERAND (t, 0)),
11196 RECUR (TREE_OPERAND (t, 1)),
11197 DELETE_EXPR_USE_VEC (t),
11198 DELETE_EXPR_USE_GLOBAL (t));
11200 case COMPOUND_EXPR:
11201 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
11202 RECUR (TREE_OPERAND (t, 1)),
11212 function = CALL_EXPR_FN (t);
11213 /* When we parsed the expression, we determined whether or
11214 not Koenig lookup should be performed. */
11215 koenig_p = KOENIG_LOOKUP_P (t);
11216 if (TREE_CODE (function) == SCOPE_REF)
11218 qualified_p = true;
11219 function = tsubst_qualified_id (function, args, complain, in_decl,
11221 /*address_p=*/false);
11225 if (TREE_CODE (function) == COMPONENT_REF)
11227 tree op = TREE_OPERAND (function, 1);
11229 qualified_p = (TREE_CODE (op) == SCOPE_REF
11230 || (BASELINK_P (op)
11231 && BASELINK_QUALIFIED_P (op)));
11234 qualified_p = false;
11236 function = tsubst_copy_and_build (function, args, complain,
11239 integral_constant_expression_p);
11241 if (BASELINK_P (function))
11242 qualified_p = true;
11245 /* FIXME: Rewrite this so as not to construct an arglist. */
11246 call_args = RECUR (CALL_EXPR_ARGS (t));
11248 /* We do not perform argument-dependent lookup if normal
11249 lookup finds a non-function, in accordance with the
11250 expected resolution of DR 218. */
11252 && ((is_overloaded_fn (function)
11253 /* If lookup found a member function, the Koenig lookup is
11254 not appropriate, even if an unqualified-name was used
11255 to denote the function. */
11256 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
11257 || TREE_CODE (function) == IDENTIFIER_NODE))
11258 function = perform_koenig_lookup (function, call_args);
11260 if (TREE_CODE (function) == IDENTIFIER_NODE)
11262 unqualified_name_lookup_error (function);
11263 return error_mark_node;
11266 /* Remember that there was a reference to this entity. */
11267 if (DECL_P (function))
11268 mark_used (function);
11270 if (TREE_CODE (function) == OFFSET_REF)
11271 return build_offset_ref_call_from_tree (function, call_args);
11272 if (TREE_CODE (function) == COMPONENT_REF)
11274 if (!BASELINK_P (TREE_OPERAND (function, 1)))
11275 return finish_call_expr (function, call_args,
11276 /*disallow_virtual=*/false,
11277 /*koenig_p=*/false,
11280 return (build_new_method_call
11281 (TREE_OPERAND (function, 0),
11282 TREE_OPERAND (function, 1),
11283 call_args, NULL_TREE,
11284 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
11288 return finish_call_expr (function, call_args,
11289 /*disallow_virtual=*/qualified_p,
11295 return build_x_conditional_expr
11296 (RECUR (TREE_OPERAND (t, 0)),
11297 RECUR (TREE_OPERAND (t, 1)),
11298 RECUR (TREE_OPERAND (t, 2)),
11301 case PSEUDO_DTOR_EXPR:
11302 return finish_pseudo_destructor_expr
11303 (RECUR (TREE_OPERAND (t, 0)),
11304 RECUR (TREE_OPERAND (t, 1)),
11305 RECUR (TREE_OPERAND (t, 2)));
11309 tree purpose, value, chain;
11311 if (t == void_list_node)
11314 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
11315 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
11317 /* We have pack expansions, so expand those and
11318 create a new list out of it. */
11319 tree purposevec = NULL_TREE;
11320 tree valuevec = NULL_TREE;
11324 /* Expand the argument expressions. */
11325 if (TREE_PURPOSE (t))
11326 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
11327 complain, in_decl);
11328 if (TREE_VALUE (t))
11329 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
11330 complain, in_decl);
11332 /* Build the rest of the list. */
11333 chain = TREE_CHAIN (t);
11334 if (chain && chain != void_type_node)
11335 chain = RECUR (chain);
11337 /* Determine the number of arguments. */
11338 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
11340 len = TREE_VEC_LENGTH (purposevec);
11341 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
11343 else if (TREE_CODE (valuevec) == TREE_VEC)
11344 len = TREE_VEC_LENGTH (valuevec);
11347 /* Since we only performed a partial substitution into
11348 the argument pack, we only return a single list
11350 if (purposevec == TREE_PURPOSE (t)
11351 && valuevec == TREE_VALUE (t)
11352 && chain == TREE_CHAIN (t))
11355 return tree_cons (purposevec, valuevec, chain);
11358 /* Convert the argument vectors into a TREE_LIST */
11362 /* Grab the Ith values. */
11364 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
11367 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
11370 /* Build the list (backwards). */
11371 chain = tree_cons (purpose, value, chain);
11377 purpose = TREE_PURPOSE (t);
11379 purpose = RECUR (purpose);
11380 value = TREE_VALUE (t);
11382 value = RECUR (value);
11383 chain = TREE_CHAIN (t);
11384 if (chain && chain != void_type_node)
11385 chain = RECUR (chain);
11386 if (purpose == TREE_PURPOSE (t)
11387 && value == TREE_VALUE (t)
11388 && chain == TREE_CHAIN (t))
11390 return tree_cons (purpose, value, chain);
11393 case COMPONENT_REF:
11399 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11400 args, complain, in_decl);
11401 /* Remember that there was a reference to this entity. */
11402 if (DECL_P (object))
11403 mark_used (object);
11404 object_type = TREE_TYPE (object);
11406 member = TREE_OPERAND (t, 1);
11407 if (BASELINK_P (member))
11408 member = tsubst_baselink (member,
11409 non_reference (TREE_TYPE (object)),
11410 args, complain, in_decl);
11412 member = tsubst_copy (member, args, complain, in_decl);
11413 if (member == error_mark_node)
11414 return error_mark_node;
11416 if (object_type && !CLASS_TYPE_P (object_type))
11418 if (SCALAR_TYPE_P (object_type))
11420 tree s = NULL_TREE;
11421 tree dtor = member;
11423 if (TREE_CODE (dtor) == SCOPE_REF)
11425 s = TREE_OPERAND (dtor, 0);
11426 dtor = TREE_OPERAND (dtor, 1);
11428 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
11430 dtor = TREE_OPERAND (dtor, 0);
11432 return finish_pseudo_destructor_expr (object, s, dtor);
11436 else if (TREE_CODE (member) == SCOPE_REF
11437 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
11442 /* Lookup the template functions now that we know what the
11444 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
11445 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
11446 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
11447 /*is_type_p=*/false,
11448 /*complain=*/false);
11449 if (BASELINK_P (member))
11451 BASELINK_FUNCTIONS (member)
11452 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
11454 member = (adjust_result_of_qualified_name_lookup
11455 (member, BINFO_TYPE (BASELINK_BINFO (member)),
11460 qualified_name_lookup_error (object_type, tmpl, member,
11462 return error_mark_node;
11465 else if (TREE_CODE (member) == SCOPE_REF
11466 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
11467 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
11469 if (complain & tf_error)
11471 if (TYPE_P (TREE_OPERAND (member, 0)))
11472 error ("%qT is not a class or namespace",
11473 TREE_OPERAND (member, 0));
11475 error ("%qD is not a class or namespace",
11476 TREE_OPERAND (member, 0));
11478 return error_mark_node;
11480 else if (TREE_CODE (member) == FIELD_DECL)
11481 return finish_non_static_data_member (member, object, NULL_TREE);
11483 return finish_class_member_access_expr (object, member,
11484 /*template_p=*/false,
11490 (RECUR (TREE_OPERAND (t, 0)));
11494 VEC(constructor_elt,gc) *n;
11495 constructor_elt *ce;
11496 unsigned HOST_WIDE_INT idx;
11497 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11498 bool process_index_p;
11500 bool need_copy_p = false;
11503 if (type == error_mark_node)
11504 return error_mark_node;
11506 /* digest_init will do the wrong thing if we let it. */
11507 if (type && TYPE_PTRMEMFUNC_P (type))
11510 /* We do not want to process the index of aggregate
11511 initializers as they are identifier nodes which will be
11512 looked up by digest_init. */
11513 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
11515 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
11516 newlen = VEC_length (constructor_elt, n);
11517 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
11519 if (ce->index && process_index_p)
11520 ce->index = RECUR (ce->index);
11522 if (PACK_EXPANSION_P (ce->value))
11524 /* Substitute into the pack expansion. */
11525 ce->value = tsubst_pack_expansion (ce->value, args, complain,
11528 if (ce->value == error_mark_node)
11530 else if (TREE_VEC_LENGTH (ce->value) == 1)
11531 /* Just move the argument into place. */
11532 ce->value = TREE_VEC_ELT (ce->value, 0);
11535 /* Update the length of the final CONSTRUCTOR
11536 arguments vector, and note that we will need to
11538 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
11539 need_copy_p = true;
11543 ce->value = RECUR (ce->value);
11548 VEC(constructor_elt,gc) *old_n = n;
11550 n = VEC_alloc (constructor_elt, gc, newlen);
11551 for (idx = 0; VEC_iterate (constructor_elt, old_n, idx, ce);
11554 if (TREE_CODE (ce->value) == TREE_VEC)
11556 int i, len = TREE_VEC_LENGTH (ce->value);
11557 for (i = 0; i < len; ++i)
11558 CONSTRUCTOR_APPEND_ELT (n, 0,
11559 TREE_VEC_ELT (ce->value, i));
11562 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
11566 r = build_constructor (init_list_type_node, n);
11568 if (TREE_HAS_CONSTRUCTOR (t))
11569 return finish_compound_literal (type, r);
11576 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
11577 if (TYPE_P (operand_0))
11578 return get_typeid (operand_0);
11579 return build_typeid (operand_0);
11589 tree r = tsubst_copy (t, args, complain, in_decl);
11591 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
11592 /* If the original type was a reference, we'll be wrapped in
11593 the appropriate INDIRECT_REF. */
11594 r = convert_from_reference (r);
11599 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
11600 tsubst_copy (TREE_TYPE (t), args, complain,
11603 case OFFSETOF_EXPR:
11604 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
11608 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
11609 complain, in_decl);
11611 tree type2 = TRAIT_EXPR_TYPE2 (t);
11613 type2 = tsubst_copy (type2, args, complain, in_decl);
11615 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
11620 tree old_stmt_expr = cur_stmt_expr;
11621 tree stmt_expr = begin_stmt_expr ();
11623 cur_stmt_expr = stmt_expr;
11624 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
11625 integral_constant_expression_p);
11626 stmt_expr = finish_stmt_expr (stmt_expr, false);
11627 cur_stmt_expr = old_stmt_expr;
11633 t = tsubst_copy (t, args, complain, in_decl);
11634 /* As in finish_id_expression, we resolve enumeration constants
11635 to their underlying values. */
11636 if (TREE_CODE (t) == CONST_DECL)
11638 used_types_insert (TREE_TYPE (t));
11639 return DECL_INITIAL (t);
11644 /* Handle Objective-C++ constructs, if appropriate. */
11647 = objcp_tsubst_copy_and_build (t, args, complain,
11648 in_decl, /*function_p=*/false);
11652 return tsubst_copy (t, args, complain, in_decl);
11658 /* Verify that the instantiated ARGS are valid. For type arguments,
11659 make sure that the type's linkage is ok. For non-type arguments,
11660 make sure they are constants if they are integral or enumerations.
11661 Emit an error under control of COMPLAIN, and return TRUE on error. */
11664 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
11666 int ix, len = DECL_NTPARMS (tmpl);
11667 bool result = false;
11669 for (ix = 0; ix != len; ix++)
11671 tree t = TREE_VEC_ELT (args, ix);
11675 /* [basic.link]: A name with no linkage (notably, the name
11676 of a class or enumeration declared in a local scope)
11677 shall not be used to declare an entity with linkage.
11678 This implies that names with no linkage cannot be used as
11679 template arguments. */
11680 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
11684 /* DR 488 makes use of a type with no linkage cause
11685 type deduction to fail. */
11686 if (complain & tf_error)
11688 if (TYPE_ANONYMOUS_P (nt))
11689 error ("%qT is/uses anonymous type", t);
11691 error ("template argument for %qD uses local type %qT",
11696 /* In order to avoid all sorts of complications, we do not
11697 allow variably-modified types as template arguments. */
11698 else if (variably_modified_type_p (t, NULL_TREE))
11700 if (complain & tf_error)
11701 error ("%qT is a variably modified type", t);
11705 /* A non-type argument of integral or enumerated type must be a
11707 else if (TREE_TYPE (t)
11708 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
11709 && !TREE_CONSTANT (t))
11711 if (complain & tf_error)
11712 error ("integral expression %qE is not constant", t);
11716 if (result && (complain & tf_error))
11717 error (" trying to instantiate %qD", tmpl);
11721 /* Instantiate the indicated variable or function template TMPL with
11722 the template arguments in TARG_PTR. */
11725 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
11730 HOST_WIDE_INT saved_processing_template_decl;
11732 if (tmpl == error_mark_node)
11733 return error_mark_node;
11735 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
11737 /* If this function is a clone, handle it specially. */
11738 if (DECL_CLONED_FUNCTION_P (tmpl))
11743 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
11745 if (spec == error_mark_node)
11746 return error_mark_node;
11748 /* Look for the clone. */
11749 FOR_EACH_CLONE (clone, spec)
11750 if (DECL_NAME (clone) == DECL_NAME (tmpl))
11752 /* We should always have found the clone by now. */
11753 gcc_unreachable ();
11757 /* Check to see if we already have this specialization. */
11758 spec = retrieve_specialization (tmpl, targ_ptr,
11759 /*class_specializations_p=*/false);
11760 if (spec != NULL_TREE)
11763 gen_tmpl = most_general_template (tmpl);
11764 if (tmpl != gen_tmpl)
11766 /* The TMPL is a partial instantiation. To get a full set of
11767 arguments we must add the arguments used to perform the
11768 partial instantiation. */
11769 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
11772 /* Check to see if we already have this specialization. */
11773 spec = retrieve_specialization (gen_tmpl, targ_ptr,
11774 /*class_specializations_p=*/false);
11775 if (spec != NULL_TREE)
11779 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
11781 return error_mark_node;
11783 /* We are building a FUNCTION_DECL, during which the access of its
11784 parameters and return types have to be checked. However this
11785 FUNCTION_DECL which is the desired context for access checking
11786 is not built yet. We solve this chicken-and-egg problem by
11787 deferring all checks until we have the FUNCTION_DECL. */
11788 push_deferring_access_checks (dk_deferred);
11790 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
11791 (because, for example, we have encountered a non-dependent
11792 function call in the body of a template function and must now
11793 determine which of several overloaded functions will be called),
11794 within the instantiation itself we are not processing a
11796 saved_processing_template_decl = processing_template_decl;
11797 processing_template_decl = 0;
11798 /* Substitute template parameters to obtain the specialization. */
11799 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
11800 targ_ptr, complain, gen_tmpl);
11801 processing_template_decl = saved_processing_template_decl;
11802 if (fndecl == error_mark_node)
11803 return error_mark_node;
11805 /* Now we know the specialization, compute access previously
11807 push_access_scope (fndecl);
11808 perform_deferred_access_checks ();
11809 pop_access_scope (fndecl);
11810 pop_deferring_access_checks ();
11812 /* The DECL_TI_TEMPLATE should always be the immediate parent
11813 template, not the most general template. */
11814 DECL_TI_TEMPLATE (fndecl) = tmpl;
11816 /* If we've just instantiated the main entry point for a function,
11817 instantiate all the alternate entry points as well. We do this
11818 by cloning the instantiation of the main entry point, not by
11819 instantiating the template clones. */
11820 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
11821 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
11826 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
11827 arguments that are being used when calling it. TARGS is a vector
11828 into which the deduced template arguments are placed.
11830 Return zero for success, 2 for an incomplete match that doesn't resolve
11831 all the types, and 1 for complete failure. An error message will be
11832 printed only for an incomplete match.
11834 If FN is a conversion operator, or we are trying to produce a specific
11835 specialization, RETURN_TYPE is the return type desired.
11837 The EXPLICIT_TARGS are explicit template arguments provided via a
11840 The parameter STRICT is one of:
11843 We are deducing arguments for a function call, as in
11844 [temp.deduct.call].
11847 We are deducing arguments for a conversion function, as in
11848 [temp.deduct.conv].
11851 We are deducing arguments when doing an explicit instantiation
11852 as in [temp.explicit], when determining an explicit specialization
11853 as in [temp.expl.spec], or when taking the address of a function
11854 template, as in [temp.deduct.funcaddr]. */
11857 fn_type_unification (tree fn,
11858 tree explicit_targs,
11862 unification_kind_t strict,
11868 bool incomplete_argument_packs_p = false;
11870 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
11872 fntype = TREE_TYPE (fn);
11873 if (explicit_targs)
11877 The specified template arguments must match the template
11878 parameters in kind (i.e., type, nontype, template), and there
11879 must not be more arguments than there are parameters;
11880 otherwise type deduction fails.
11882 Nontype arguments must match the types of the corresponding
11883 nontype template parameters, or must be convertible to the
11884 types of the corresponding nontype parameters as specified in
11885 _temp.arg.nontype_, otherwise type deduction fails.
11887 All references in the function type of the function template
11888 to the corresponding template parameters are replaced by the
11889 specified template argument values. If a substitution in a
11890 template parameter or in the function type of the function
11891 template results in an invalid type, type deduction fails. */
11892 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
11893 int i, len = TREE_VEC_LENGTH (tparms);
11894 tree converted_args;
11895 bool incomplete = false;
11897 if (explicit_targs == error_mark_node)
11901 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
11902 /*require_all_args=*/false,
11903 /*use_default_args=*/false));
11904 if (converted_args == error_mark_node)
11907 /* Substitute the explicit args into the function type. This is
11908 necessary so that, for instance, explicitly declared function
11909 arguments can match null pointed constants. If we were given
11910 an incomplete set of explicit args, we must not do semantic
11911 processing during substitution as we could create partial
11913 for (i = 0; i < len; i++)
11915 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
11916 bool parameter_pack = false;
11918 /* Dig out the actual parm. */
11919 if (TREE_CODE (parm) == TYPE_DECL
11920 || TREE_CODE (parm) == TEMPLATE_DECL)
11922 parm = TREE_TYPE (parm);
11923 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
11925 else if (TREE_CODE (parm) == PARM_DECL)
11927 parm = DECL_INITIAL (parm);
11928 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
11931 if (parameter_pack)
11935 template_parm_level_and_index (parm, &level, &idx);
11937 /* Mark the argument pack as "incomplete". We could
11938 still deduce more arguments during unification. */
11939 targ = TMPL_ARG (converted_args, level, idx);
11942 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
11943 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
11944 = ARGUMENT_PACK_ARGS (targ);
11947 /* We have some incomplete argument packs. */
11948 incomplete_argument_packs_p = true;
11952 if (incomplete_argument_packs_p)
11953 /* Any substitution is guaranteed to be incomplete if there
11954 are incomplete argument packs, because we can still deduce
11958 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
11960 processing_template_decl += incomplete;
11961 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
11962 processing_template_decl -= incomplete;
11964 if (fntype == error_mark_node)
11967 /* Place the explicitly specified arguments in TARGS. */
11968 for (i = NUM_TMPL_ARGS (converted_args); i--;)
11969 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
11972 /* Never do unification on the 'this' parameter. */
11973 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
11977 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
11978 args = tree_cons (NULL_TREE, return_type, args);
11981 /* We allow incomplete unification without an error message here
11982 because the standard doesn't seem to explicitly prohibit it. Our
11983 callers must be ready to deal with unification failures in any
11985 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
11986 targs, parms, args, /*subr=*/0,
11989 if (result == 0 && incomplete_argument_packs_p)
11991 int i, len = NUM_TMPL_ARGS (targs);
11993 /* Clear the "incomplete" flags on all argument packs. */
11994 for (i = 0; i < len; i++)
11996 tree arg = TREE_VEC_ELT (targs, i);
11997 if (ARGUMENT_PACK_P (arg))
11999 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
12000 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
12005 /* Now that we have bindings for all of the template arguments,
12006 ensure that the arguments deduced for the template template
12007 parameters have compatible template parameter lists. We cannot
12008 check this property before we have deduced all template
12009 arguments, because the template parameter types of a template
12010 template parameter might depend on prior template parameters
12011 deduced after the template template parameter. The following
12012 ill-formed example illustrates this issue:
12014 template<typename T, template<T> class C> void f(C<5>, T);
12016 template<int N> struct X {};
12019 f(X<5>(), 5l); // error: template argument deduction fails
12022 The template parameter list of 'C' depends on the template type
12023 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
12024 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
12025 time that we deduce 'C'. */
12027 && !template_template_parm_bindings_ok_p
12028 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
12032 /* All is well so far. Now, check:
12036 When all template arguments have been deduced, all uses of
12037 template parameters in nondeduced contexts are replaced with
12038 the corresponding deduced argument values. If the
12039 substitution results in an invalid type, as described above,
12040 type deduction fails. */
12041 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
12042 == error_mark_node)
12048 /* Adjust types before performing type deduction, as described in
12049 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
12050 sections are symmetric. PARM is the type of a function parameter
12051 or the return type of the conversion function. ARG is the type of
12052 the argument passed to the call, or the type of the value
12053 initialized with the result of the conversion function.
12054 ARG_EXPR is the original argument expression, which may be null. */
12057 maybe_adjust_types_for_deduction (unification_kind_t strict,
12071 /* Swap PARM and ARG throughout the remainder of this
12072 function; the handling is precisely symmetric since PARM
12073 will initialize ARG rather than vice versa. */
12081 /* There is nothing to do in this case. */
12085 gcc_unreachable ();
12088 if (TREE_CODE (*parm) != REFERENCE_TYPE)
12090 /* [temp.deduct.call]
12092 If P is not a reference type:
12094 --If A is an array type, the pointer type produced by the
12095 array-to-pointer standard conversion (_conv.array_) is
12096 used in place of A for type deduction; otherwise,
12098 --If A is a function type, the pointer type produced by
12099 the function-to-pointer standard conversion
12100 (_conv.func_) is used in place of A for type deduction;
12103 --If A is a cv-qualified type, the top level
12104 cv-qualifiers of A's type are ignored for type
12106 if (TREE_CODE (*arg) == ARRAY_TYPE)
12107 *arg = build_pointer_type (TREE_TYPE (*arg));
12108 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
12109 *arg = build_pointer_type (*arg);
12111 *arg = TYPE_MAIN_VARIANT (*arg);
12114 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
12115 of the form T&&, where T is a template parameter, and the argument
12116 is an lvalue, T is deduced as A& */
12117 if (TREE_CODE (*parm) == REFERENCE_TYPE
12118 && TYPE_REF_IS_RVALUE (*parm)
12119 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
12120 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
12121 && arg_expr && real_lvalue_p (arg_expr))
12122 *arg = build_reference_type (*arg);
12124 /* [temp.deduct.call]
12126 If P is a cv-qualified type, the top level cv-qualifiers
12127 of P's type are ignored for type deduction. If P is a
12128 reference type, the type referred to by P is used for
12130 *parm = TYPE_MAIN_VARIANT (*parm);
12131 if (TREE_CODE (*parm) == REFERENCE_TYPE)
12133 *parm = TREE_TYPE (*parm);
12134 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
12137 /* DR 322. For conversion deduction, remove a reference type on parm
12138 too (which has been swapped into ARG). */
12139 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
12140 *arg = TREE_TYPE (*arg);
12145 /* Most parms like fn_type_unification.
12147 If SUBR is 1, we're being called recursively (to unify the
12148 arguments of a function or method parameter of a function
12152 type_unification_real (tree tparms,
12157 unification_kind_t strict,
12160 tree parm, arg, arg_expr;
12162 int ntparms = TREE_VEC_LENGTH (tparms);
12164 int saw_undeduced = 0;
12167 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
12168 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
12169 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
12170 gcc_assert (ntparms > 0);
12175 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
12176 | UNIFY_ALLOW_DERIVED);
12180 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
12184 sub_strict = UNIFY_ALLOW_NONE;
12188 gcc_unreachable ();
12195 while (parms && parms != void_list_node
12196 && args && args != void_list_node)
12198 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
12201 parm = TREE_VALUE (parms);
12202 parms = TREE_CHAIN (parms);
12203 arg = TREE_VALUE (args);
12204 args = TREE_CHAIN (args);
12207 if (arg == error_mark_node)
12209 if (arg == unknown_type_node)
12210 /* We can't deduce anything from this, but we might get all the
12211 template args from other function args. */
12214 /* Conversions will be performed on a function argument that
12215 corresponds with a function parameter that contains only
12216 non-deducible template parameters and explicitly specified
12217 template parameters. */
12218 if (!uses_template_parms (parm))
12223 type = TREE_TYPE (arg);
12227 if (same_type_p (parm, type))
12229 if (strict != DEDUCE_EXACT
12230 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
12239 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
12240 if (type_unknown_p (arg))
12242 /* [temp.deduct.type]
12244 A template-argument can be deduced from a pointer to
12245 function or pointer to member function argument if
12246 the set of overloaded functions does not contain
12247 function templates and at most one of a set of
12248 overloaded functions provides a unique match. */
12249 if (resolve_overloaded_unification
12250 (tparms, targs, parm, arg, strict, sub_strict))
12256 arg = unlowered_expr_type (arg);
12257 if (arg == error_mark_node)
12262 int arg_strict = sub_strict;
12265 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
12268 if (arg == init_list_type_node && arg_expr)
12270 if (unify (tparms, targs, parm, arg, arg_strict))
12277 && parms != void_list_node
12278 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
12280 /* Unify the remaining arguments with the pack expansion type. */
12282 tree parmvec = make_tree_vec (1);
12286 /* Count the number of arguments that remain. */
12287 for (t = args; t && t != void_list_node; t = TREE_CHAIN (t))
12290 /* Allocate a TREE_VEC and copy in all of the arguments */
12291 argvec = make_tree_vec (len);
12292 for (i = 0; args && args != void_list_node; args = TREE_CHAIN (args))
12294 TREE_VEC_ELT (argvec, i) = TREE_VALUE (args);
12298 /* Copy the parameter into parmvec. */
12299 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
12300 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
12301 /*call_args_p=*/true, /*subr=*/subr))
12304 /* Advance to the end of the list of parameters. */
12305 parms = TREE_CHAIN (parms);
12308 /* Fail if we've reached the end of the parm list, and more args
12309 are present, and the parm list isn't variadic. */
12310 if (args && args != void_list_node && parms == void_list_node)
12312 /* Fail if parms are left and they don't have default values. */
12313 if (parms && parms != void_list_node
12314 && TREE_PURPOSE (parms) == NULL_TREE)
12318 for (i = 0; i < ntparms; i++)
12319 if (!TREE_VEC_ELT (targs, i))
12323 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
12326 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
12328 /* If this is an undeduced nontype parameter that depends on
12329 a type parameter, try another pass; its type may have been
12330 deduced from a later argument than the one from which
12331 this parameter can be deduced. */
12332 if (TREE_CODE (tparm) == PARM_DECL
12333 && uses_template_parms (TREE_TYPE (tparm))
12334 && !saw_undeduced++)
12337 /* Core issue #226 (C++0x) [temp.deduct]:
12339 If a template argument has not been deduced, its
12340 default template argument, if any, is used.
12342 When we are in C++98 mode, TREE_PURPOSE will either
12343 be NULL_TREE or ERROR_MARK_NODE, so we do not need
12344 to explicitly check cxx_dialect here. */
12345 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
12347 tree arg = tsubst (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)),
12348 targs, tf_none, NULL_TREE);
12349 if (arg == error_mark_node)
12353 TREE_VEC_ELT (targs, i) = arg;
12358 /* If the type parameter is a parameter pack, then it will
12359 be deduced to an empty parameter pack. */
12360 if (template_parameter_pack_p (tparm))
12364 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
12366 arg = make_node (NONTYPE_ARGUMENT_PACK);
12367 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
12368 TREE_CONSTANT (arg) = 1;
12371 arg = make_node (TYPE_ARGUMENT_PACK);
12373 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
12375 TREE_VEC_ELT (targs, i) = arg;
12385 /* Subroutine of type_unification_real. Args are like the variables
12386 at the call site. ARG is an overloaded function (or template-id);
12387 we try deducing template args from each of the overloads, and if
12388 only one succeeds, we go with that. Modifies TARGS and returns
12389 true on success. */
12392 resolve_overloaded_unification (tree tparms,
12396 unification_kind_t strict,
12399 tree tempargs = copy_node (targs);
12403 if (TREE_CODE (arg) == ADDR_EXPR)
12405 arg = TREE_OPERAND (arg, 0);
12411 if (TREE_CODE (arg) == COMPONENT_REF)
12412 /* Handle `&x' where `x' is some static or non-static member
12414 arg = TREE_OPERAND (arg, 1);
12416 if (TREE_CODE (arg) == OFFSET_REF)
12417 arg = TREE_OPERAND (arg, 1);
12419 /* Strip baselink information. */
12420 if (BASELINK_P (arg))
12421 arg = BASELINK_FUNCTIONS (arg);
12423 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
12425 /* If we got some explicit template args, we need to plug them into
12426 the affected templates before we try to unify, in case the
12427 explicit args will completely resolve the templates in question. */
12429 tree expl_subargs = TREE_OPERAND (arg, 1);
12430 arg = TREE_OPERAND (arg, 0);
12432 for (; arg; arg = OVL_NEXT (arg))
12434 tree fn = OVL_CURRENT (arg);
12435 tree subargs, elem;
12437 if (TREE_CODE (fn) != TEMPLATE_DECL)
12440 ++processing_template_decl;
12441 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
12442 expl_subargs, /*check_ret=*/false);
12445 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
12446 good += try_one_overload (tparms, targs, tempargs, parm,
12447 elem, strict, sub_strict, addr_p);
12449 --processing_template_decl;
12452 else if (TREE_CODE (arg) != OVERLOAD
12453 && TREE_CODE (arg) != FUNCTION_DECL)
12454 /* If ARG is, for example, "(0, &f)" then its type will be unknown
12455 -- but the deduction does not succeed because the expression is
12456 not just the function on its own. */
12459 for (; arg; arg = OVL_NEXT (arg))
12460 good += try_one_overload (tparms, targs, tempargs, parm,
12461 TREE_TYPE (OVL_CURRENT (arg)),
12462 strict, sub_strict, addr_p);
12464 /* [temp.deduct.type] A template-argument can be deduced from a pointer
12465 to function or pointer to member function argument if the set of
12466 overloaded functions does not contain function templates and at most
12467 one of a set of overloaded functions provides a unique match.
12469 So if we found multiple possibilities, we return success but don't
12470 deduce anything. */
12474 int i = TREE_VEC_LENGTH (targs);
12476 if (TREE_VEC_ELT (tempargs, i))
12477 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
12485 /* Subroutine of resolve_overloaded_unification; does deduction for a single
12486 overload. Fills TARGS with any deduced arguments, or error_mark_node if
12487 different overloads deduce different arguments for a given parm.
12488 ADDR_P is true if the expression for which deduction is being
12489 performed was of the form "& fn" rather than simply "fn".
12491 Returns 1 on success. */
12494 try_one_overload (tree tparms,
12499 unification_kind_t strict,
12507 /* [temp.deduct.type] A template-argument can be deduced from a pointer
12508 to function or pointer to member function argument if the set of
12509 overloaded functions does not contain function templates and at most
12510 one of a set of overloaded functions provides a unique match.
12512 So if this is a template, just return success. */
12514 if (uses_template_parms (arg))
12517 if (TREE_CODE (arg) == METHOD_TYPE)
12518 arg = build_ptrmemfunc_type (build_pointer_type (arg));
12520 arg = build_pointer_type (arg);
12522 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
12524 /* We don't copy orig_targs for this because if we have already deduced
12525 some template args from previous args, unify would complain when we
12526 try to deduce a template parameter for the same argument, even though
12527 there isn't really a conflict. */
12528 nargs = TREE_VEC_LENGTH (targs);
12529 tempargs = make_tree_vec (nargs);
12531 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
12534 /* First make sure we didn't deduce anything that conflicts with
12535 explicitly specified args. */
12536 for (i = nargs; i--; )
12538 tree elt = TREE_VEC_ELT (tempargs, i);
12539 tree oldelt = TREE_VEC_ELT (orig_targs, i);
12543 else if (uses_template_parms (elt))
12544 /* Since we're unifying against ourselves, we will fill in
12545 template args used in the function parm list with our own
12546 template parms. Discard them. */
12547 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
12548 else if (oldelt && !template_args_equal (oldelt, elt))
12552 for (i = nargs; i--; )
12554 tree elt = TREE_VEC_ELT (tempargs, i);
12557 TREE_VEC_ELT (targs, i) = elt;
12563 /* PARM is a template class (perhaps with unbound template
12564 parameters). ARG is a fully instantiated type. If ARG can be
12565 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
12566 TARGS are as for unify. */
12569 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
12571 tree copy_of_targs;
12573 if (!CLASSTYPE_TEMPLATE_INFO (arg)
12574 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
12575 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
12578 /* We need to make a new template argument vector for the call to
12579 unify. If we used TARGS, we'd clutter it up with the result of
12580 the attempted unification, even if this class didn't work out.
12581 We also don't want to commit ourselves to all the unifications
12582 we've already done, since unification is supposed to be done on
12583 an argument-by-argument basis. In other words, consider the
12584 following pathological case:
12586 template <int I, int J, int K>
12589 template <int I, int J>
12590 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
12592 template <int I, int J, int K>
12593 void f(S<I, J, K>, S<I, I, I>);
12602 Now, by the time we consider the unification involving `s2', we
12603 already know that we must have `f<0, 0, 0>'. But, even though
12604 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
12605 because there are two ways to unify base classes of S<0, 1, 2>
12606 with S<I, I, I>. If we kept the already deduced knowledge, we
12607 would reject the possibility I=1. */
12608 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
12610 /* If unification failed, we're done. */
12611 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
12612 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
12618 /* Given a template type PARM and a class type ARG, find the unique
12619 base type in ARG that is an instance of PARM. We do not examine
12620 ARG itself; only its base-classes. If there is not exactly one
12621 appropriate base class, return NULL_TREE. PARM may be the type of
12622 a partial specialization, as well as a plain template type. Used
12626 get_template_base (tree tparms, tree targs, tree parm, tree arg)
12628 tree rval = NULL_TREE;
12631 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
12633 binfo = TYPE_BINFO (complete_type (arg));
12635 /* The type could not be completed. */
12638 /* Walk in inheritance graph order. The search order is not
12639 important, and this avoids multiple walks of virtual bases. */
12640 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
12642 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
12646 /* If there is more than one satisfactory baseclass, then:
12650 If they yield more than one possible deduced A, the type
12654 if (rval && !same_type_p (r, rval))
12664 /* Returns the level of DECL, which declares a template parameter. */
12667 template_decl_level (tree decl)
12669 switch (TREE_CODE (decl))
12672 case TEMPLATE_DECL:
12673 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
12676 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
12679 gcc_unreachable ();
12684 /* Decide whether ARG can be unified with PARM, considering only the
12685 cv-qualifiers of each type, given STRICT as documented for unify.
12686 Returns nonzero iff the unification is OK on that basis. */
12689 check_cv_quals_for_unify (int strict, tree arg, tree parm)
12691 int arg_quals = cp_type_quals (arg);
12692 int parm_quals = cp_type_quals (parm);
12694 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
12695 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
12697 /* Although a CVR qualifier is ignored when being applied to a
12698 substituted template parameter ([8.3.2]/1 for example), that
12699 does not apply during deduction [14.8.2.4]/1, (even though
12700 that is not explicitly mentioned, [14.8.2.4]/9 indicates
12701 this). Except when we're allowing additional CV qualifiers
12702 at the outer level [14.8.2.1]/3,1st bullet. */
12703 if ((TREE_CODE (arg) == REFERENCE_TYPE
12704 || TREE_CODE (arg) == FUNCTION_TYPE
12705 || TREE_CODE (arg) == METHOD_TYPE)
12706 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
12709 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
12710 && (parm_quals & TYPE_QUAL_RESTRICT))
12714 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
12715 && (arg_quals & parm_quals) != parm_quals)
12718 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
12719 && (parm_quals & arg_quals) != arg_quals)
12725 /* Determines the LEVEL and INDEX for the template parameter PARM. */
12727 template_parm_level_and_index (tree parm, int* level, int* index)
12729 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
12730 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
12731 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
12733 *index = TEMPLATE_TYPE_IDX (parm);
12734 *level = TEMPLATE_TYPE_LEVEL (parm);
12738 *index = TEMPLATE_PARM_IDX (parm);
12739 *level = TEMPLATE_PARM_LEVEL (parm);
12743 /* Unifies the remaining arguments in PACKED_ARGS with the pack
12744 expansion at the end of PACKED_PARMS. Returns 0 if the type
12745 deduction succeeds, 1 otherwise. STRICT is the same as in
12746 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
12747 call argument list. We'll need to adjust the arguments to make them
12748 types. SUBR tells us if this is from a recursive call to
12749 type_unification_real. */
12751 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
12752 tree packed_args, int strict, bool call_args_p,
12756 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
12757 tree pattern = PACK_EXPANSION_PATTERN (parm);
12758 tree pack, packs = NULL_TREE;
12759 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
12760 int len = TREE_VEC_LENGTH (packed_args);
12762 /* Determine the parameter packs we will be deducing from the
12763 pattern, and record their current deductions. */
12764 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
12765 pack; pack = TREE_CHAIN (pack))
12767 tree parm_pack = TREE_VALUE (pack);
12770 /* Determine the index and level of this parameter pack. */
12771 template_parm_level_and_index (parm_pack, &level, &idx);
12773 /* Keep track of the parameter packs and their corresponding
12775 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
12776 TREE_TYPE (packs) = make_tree_vec (len - start);
12779 /* Loop through all of the arguments that have not yet been
12780 unified and unify each with the pattern. */
12781 for (i = start; i < len; i++)
12783 tree parm = pattern;
12785 /* For each parameter pack, clear out the deduced value so that
12786 we can deduce it again. */
12787 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12790 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12792 TMPL_ARG (targs, level, idx) = NULL_TREE;
12795 /* Unify the pattern with the current argument. */
12797 tree arg = TREE_VEC_ELT (packed_args, i);
12798 tree arg_expr = NULL_TREE;
12799 int arg_strict = strict;
12800 bool skip_arg_p = false;
12806 /* This mirrors what we do in type_unification_real. */
12810 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
12811 | UNIFY_ALLOW_MORE_CV_QUAL
12812 | UNIFY_ALLOW_DERIVED);
12816 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
12820 sub_strict = UNIFY_ALLOW_NONE;
12824 gcc_unreachable ();
12829 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
12830 if (type_unknown_p (arg))
12832 /* [temp.deduct.type] A template-argument can be
12833 deduced from a pointer to function or pointer
12834 to member function argument if the set of
12835 overloaded functions does not contain function
12836 templates and at most one of a set of
12837 overloaded functions provides a unique
12840 if (resolve_overloaded_unification
12841 (tparms, targs, parm, arg, strict, sub_strict)
12850 arg = unlowered_expr_type (arg);
12851 if (arg == error_mark_node)
12856 arg_strict = sub_strict;
12860 maybe_adjust_types_for_deduction (strict, &parm, &arg,
12866 if (unify (tparms, targs, parm, arg, arg_strict))
12871 /* For each parameter pack, collect the deduced value. */
12872 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12875 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12877 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
12878 TMPL_ARG (targs, level, idx);
12882 /* Verify that the results of unification with the parameter packs
12883 produce results consistent with what we've seen before, and make
12884 the deduced argument packs available. */
12885 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12887 tree old_pack = TREE_VALUE (pack);
12888 tree new_args = TREE_TYPE (pack);
12889 int i, len = TREE_VEC_LENGTH (new_args);
12890 bool nondeduced_p = false;
12892 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
12893 actually deduce anything. */
12894 for (i = 0; i < len && !nondeduced_p; ++i)
12895 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
12896 nondeduced_p = true;
12900 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
12902 /* Prepend the explicit arguments onto NEW_ARGS. */
12903 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
12904 tree old_args = new_args;
12905 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
12906 int len = explicit_len + TREE_VEC_LENGTH (old_args);
12908 /* Copy the explicit arguments. */
12909 new_args = make_tree_vec (len);
12910 for (i = 0; i < explicit_len; i++)
12911 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
12913 /* Copy the deduced arguments. */
12914 for (; i < len; i++)
12915 TREE_VEC_ELT (new_args, i) =
12916 TREE_VEC_ELT (old_args, i - explicit_len);
12924 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12926 /* Build the deduced *_ARGUMENT_PACK. */
12927 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
12929 result = make_node (NONTYPE_ARGUMENT_PACK);
12930 TREE_TYPE (result) =
12931 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
12932 TREE_CONSTANT (result) = 1;
12935 result = make_node (TYPE_ARGUMENT_PACK);
12937 SET_ARGUMENT_PACK_ARGS (result, new_args);
12939 /* Note the deduced argument packs for this parameter
12941 TMPL_ARG (targs, level, idx) = result;
12943 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
12944 && (ARGUMENT_PACK_ARGS (old_pack)
12945 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
12947 /* We only had the explicitly-provided arguments before, but
12948 now we have a complete set of arguments. */
12950 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
12951 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12953 /* Keep the original deduced argument pack. */
12954 TMPL_ARG (targs, level, idx) = old_pack;
12956 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
12957 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
12958 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
12960 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
12962 /* Inconsistent unification of this parameter pack. */
12968 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12970 /* Keep the original deduced argument pack. */
12971 TMPL_ARG (targs, level, idx) = old_pack;
12978 /* Deduce the value of template parameters. TPARMS is the (innermost)
12979 set of template parameters to a template. TARGS is the bindings
12980 for those template parameters, as determined thus far; TARGS may
12981 include template arguments for outer levels of template parameters
12982 as well. PARM is a parameter to a template function, or a
12983 subcomponent of that parameter; ARG is the corresponding argument.
12984 This function attempts to match PARM with ARG in a manner
12985 consistent with the existing assignments in TARGS. If more values
12986 are deduced, then TARGS is updated.
12988 Returns 0 if the type deduction succeeds, 1 otherwise. The
12989 parameter STRICT is a bitwise or of the following flags:
12992 Require an exact match between PARM and ARG.
12993 UNIFY_ALLOW_MORE_CV_QUAL:
12994 Allow the deduced ARG to be more cv-qualified (by qualification
12995 conversion) than ARG.
12996 UNIFY_ALLOW_LESS_CV_QUAL:
12997 Allow the deduced ARG to be less cv-qualified than ARG.
12998 UNIFY_ALLOW_DERIVED:
12999 Allow the deduced ARG to be a template base class of ARG,
13000 or a pointer to a template base class of the type pointed to by
13002 UNIFY_ALLOW_INTEGER:
13003 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
13004 case for more information.
13005 UNIFY_ALLOW_OUTER_LEVEL:
13006 This is the outermost level of a deduction. Used to determine validity
13007 of qualification conversions. A valid qualification conversion must
13008 have const qualified pointers leading up to the inner type which
13009 requires additional CV quals, except at the outer level, where const
13010 is not required [conv.qual]. It would be normal to set this flag in
13011 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
13012 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
13013 This is the outermost level of a deduction, and PARM can be more CV
13014 qualified at this point.
13015 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
13016 This is the outermost level of a deduction, and PARM can be less CV
13017 qualified at this point. */
13020 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
13025 int strict_in = strict;
13027 /* I don't think this will do the right thing with respect to types.
13028 But the only case I've seen it in so far has been array bounds, where
13029 signedness is the only information lost, and I think that will be
13031 while (TREE_CODE (parm) == NOP_EXPR)
13032 parm = TREE_OPERAND (parm, 0);
13034 if (arg == error_mark_node)
13036 if (arg == unknown_type_node
13037 || arg == init_list_type_node)
13038 /* We can't deduce anything from this, but we might get all the
13039 template args from other function args. */
13042 /* If PARM uses template parameters, then we can't bail out here,
13043 even if ARG == PARM, since we won't record unifications for the
13044 template parameters. We might need them if we're trying to
13045 figure out which of two things is more specialized. */
13046 if (arg == parm && !uses_template_parms (parm))
13049 /* Handle init lists early, so the rest of the function can assume
13050 we're dealing with a type. */
13051 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
13056 if (!is_std_init_list (parm))
13057 /* We can only deduce from an initializer list argument if the
13058 parameter is std::initializer_list; otherwise this is a
13059 non-deduced context. */
13062 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
13064 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
13066 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
13067 elt = TREE_TYPE (elt);
13068 if (unify (tparms, targs, elttype, elt, UNIFY_ALLOW_NONE))
13074 /* Immediately reject some pairs that won't unify because of
13075 cv-qualification mismatches. */
13076 if (TREE_CODE (arg) == TREE_CODE (parm)
13078 /* It is the elements of the array which hold the cv quals of an array
13079 type, and the elements might be template type parms. We'll check
13080 when we recurse. */
13081 && TREE_CODE (arg) != ARRAY_TYPE
13082 /* We check the cv-qualifiers when unifying with template type
13083 parameters below. We want to allow ARG `const T' to unify with
13084 PARM `T' for example, when computing which of two templates
13085 is more specialized, for example. */
13086 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
13087 && !check_cv_quals_for_unify (strict_in, arg, parm))
13090 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
13091 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
13092 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
13093 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
13094 strict &= ~UNIFY_ALLOW_DERIVED;
13095 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
13096 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
13098 switch (TREE_CODE (parm))
13100 case TYPENAME_TYPE:
13102 case UNBOUND_CLASS_TEMPLATE:
13103 /* In a type which contains a nested-name-specifier, template
13104 argument values cannot be deduced for template parameters used
13105 within the nested-name-specifier. */
13108 case TEMPLATE_TYPE_PARM:
13109 case TEMPLATE_TEMPLATE_PARM:
13110 case BOUND_TEMPLATE_TEMPLATE_PARM:
13111 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
13112 if (tparm == error_mark_node)
13115 if (TEMPLATE_TYPE_LEVEL (parm)
13116 != template_decl_level (tparm))
13117 /* The PARM is not one we're trying to unify. Just check
13118 to see if it matches ARG. */
13119 return (TREE_CODE (arg) == TREE_CODE (parm)
13120 && same_type_p (parm, arg)) ? 0 : 1;
13121 idx = TEMPLATE_TYPE_IDX (parm);
13122 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
13123 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
13125 /* Check for mixed types and values. */
13126 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13127 && TREE_CODE (tparm) != TYPE_DECL)
13128 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13129 && TREE_CODE (tparm) != TEMPLATE_DECL))
13132 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13134 /* ARG must be constructed from a template class or a template
13135 template parameter. */
13136 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
13137 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
13141 tree parmvec = TYPE_TI_ARGS (parm);
13142 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
13144 = DECL_INNERMOST_TEMPLATE_PARMS
13145 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
13147 int parm_variadic_p = 0;
13149 /* The resolution to DR150 makes clear that default
13150 arguments for an N-argument may not be used to bind T
13151 to a template template parameter with fewer than N
13152 parameters. It is not safe to permit the binding of
13153 default arguments as an extension, as that may change
13154 the meaning of a conforming program. Consider:
13156 struct Dense { static const unsigned int dim = 1; };
13158 template <template <typename> class View,
13160 void operator+(float, View<Block> const&);
13162 template <typename Block,
13163 unsigned int Dim = Block::dim>
13164 struct Lvalue_proxy { operator float() const; };
13168 Lvalue_proxy<Dense> p;
13173 Here, if Lvalue_proxy is permitted to bind to View, then
13174 the global operator+ will be used; if they are not, the
13175 Lvalue_proxy will be converted to float. */
13176 if (coerce_template_parms (parm_parms,
13178 TYPE_TI_TEMPLATE (parm),
13180 /*require_all_args=*/true,
13181 /*use_default_args=*/false)
13182 == error_mark_node)
13185 /* Deduce arguments T, i from TT<T> or TT<i>.
13186 We check each element of PARMVEC and ARGVEC individually
13187 rather than the whole TREE_VEC since they can have
13188 different number of elements. */
13190 parmvec = expand_template_argument_pack (parmvec);
13191 argvec = expand_template_argument_pack (argvec);
13193 len = TREE_VEC_LENGTH (parmvec);
13195 /* Check if the parameters end in a pack, making them
13198 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
13199 parm_variadic_p = 1;
13201 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
13204 for (i = 0; i < len - parm_variadic_p; ++i)
13206 if (unify (tparms, targs,
13207 TREE_VEC_ELT (parmvec, i),
13208 TREE_VEC_ELT (argvec, i),
13213 if (parm_variadic_p
13214 && unify_pack_expansion (tparms, targs,
13217 /*call_args_p=*/false,
13221 arg = TYPE_TI_TEMPLATE (arg);
13223 /* Fall through to deduce template name. */
13226 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13227 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13229 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
13231 /* Simple cases: Value already set, does match or doesn't. */
13232 if (targ != NULL_TREE && template_args_equal (targ, arg))
13239 /* If PARM is `const T' and ARG is only `int', we don't have
13240 a match unless we are allowing additional qualification.
13241 If ARG is `const int' and PARM is just `T' that's OK;
13242 that binds `const int' to `T'. */
13243 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
13247 /* Consider the case where ARG is `const volatile int' and
13248 PARM is `const T'. Then, T should be `volatile int'. */
13249 arg = cp_build_qualified_type_real
13250 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
13251 if (arg == error_mark_node)
13254 /* Simple cases: Value already set, does match or doesn't. */
13255 if (targ != NULL_TREE && same_type_p (targ, arg))
13260 /* Make sure that ARG is not a variable-sized array. (Note
13261 that were talking about variable-sized arrays (like
13262 `int[n]'), rather than arrays of unknown size (like
13263 `int[]').) We'll get very confused by such a type since
13264 the bound of the array will not be computable in an
13265 instantiation. Besides, such types are not allowed in
13266 ISO C++, so we can do as we please here. */
13267 if (variably_modified_type_p (arg, NULL_TREE))
13271 /* If ARG is a parameter pack or an expansion, we cannot unify
13272 against it unless PARM is also a parameter pack. */
13273 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
13274 && !template_parameter_pack_p (parm))
13277 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
13280 case TEMPLATE_PARM_INDEX:
13281 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
13282 if (tparm == error_mark_node)
13285 if (TEMPLATE_PARM_LEVEL (parm)
13286 != template_decl_level (tparm))
13287 /* The PARM is not one we're trying to unify. Just check
13288 to see if it matches ARG. */
13289 return !(TREE_CODE (arg) == TREE_CODE (parm)
13290 && cp_tree_equal (parm, arg));
13292 idx = TEMPLATE_PARM_IDX (parm);
13293 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
13296 return !cp_tree_equal (targ, arg);
13298 /* [temp.deduct.type] If, in the declaration of a function template
13299 with a non-type template-parameter, the non-type
13300 template-parameter is used in an expression in the function
13301 parameter-list and, if the corresponding template-argument is
13302 deduced, the template-argument type shall match the type of the
13303 template-parameter exactly, except that a template-argument
13304 deduced from an array bound may be of any integral type.
13305 The non-type parameter might use already deduced type parameters. */
13306 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
13307 if (!TREE_TYPE (arg))
13308 /* Template-parameter dependent expression. Just accept it for now.
13309 It will later be processed in convert_template_argument. */
13311 else if (same_type_p (TREE_TYPE (arg), tparm))
13313 else if ((strict & UNIFY_ALLOW_INTEGER)
13314 && (TREE_CODE (tparm) == INTEGER_TYPE
13315 || TREE_CODE (tparm) == BOOLEAN_TYPE))
13316 /* Convert the ARG to the type of PARM; the deduced non-type
13317 template argument must exactly match the types of the
13318 corresponding parameter. */
13319 arg = fold (build_nop (TREE_TYPE (parm), arg));
13320 else if (uses_template_parms (tparm))
13321 /* We haven't deduced the type of this parameter yet. Try again
13327 /* If ARG is a parameter pack or an expansion, we cannot unify
13328 against it unless PARM is also a parameter pack. */
13329 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
13330 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
13333 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
13338 /* A pointer-to-member constant can be unified only with
13339 another constant. */
13340 if (TREE_CODE (arg) != PTRMEM_CST)
13343 /* Just unify the class member. It would be useless (and possibly
13344 wrong, depending on the strict flags) to unify also
13345 PTRMEM_CST_CLASS, because we want to be sure that both parm and
13346 arg refer to the same variable, even if through different
13347 classes. For instance:
13349 struct A { int x; };
13352 Unification of &A::x and &B::x must succeed. */
13353 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
13354 PTRMEM_CST_MEMBER (arg), strict);
13359 if (TREE_CODE (arg) != POINTER_TYPE)
13362 /* [temp.deduct.call]
13364 A can be another pointer or pointer to member type that can
13365 be converted to the deduced A via a qualification
13366 conversion (_conv.qual_).
13368 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
13369 This will allow for additional cv-qualification of the
13370 pointed-to types if appropriate. */
13372 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
13373 /* The derived-to-base conversion only persists through one
13374 level of pointers. */
13375 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
13377 return unify (tparms, targs, TREE_TYPE (parm),
13378 TREE_TYPE (arg), strict);
13381 case REFERENCE_TYPE:
13382 if (TREE_CODE (arg) != REFERENCE_TYPE)
13384 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
13385 strict & UNIFY_ALLOW_MORE_CV_QUAL);
13388 if (TREE_CODE (arg) != ARRAY_TYPE)
13390 if ((TYPE_DOMAIN (parm) == NULL_TREE)
13391 != (TYPE_DOMAIN (arg) == NULL_TREE))
13393 if (TYPE_DOMAIN (parm) != NULL_TREE)
13400 /* Our representation of array types uses "N - 1" as the
13401 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
13402 not an integer constant. We cannot unify arbitrarily
13403 complex expressions, so we eliminate the MINUS_EXPRs
13405 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
13406 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
13409 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
13410 parm_max = TREE_OPERAND (parm_max, 0);
13412 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
13413 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
13416 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
13417 trying to unify the type of a variable with the type
13418 of a template parameter. For example:
13420 template <unsigned int N>
13421 void f (char (&) [N]);
13428 Here, the type of the ARG will be "int [g(i)]", and
13429 may be a SAVE_EXPR, etc. */
13430 if (TREE_CODE (arg_max) != MINUS_EXPR)
13432 arg_max = TREE_OPERAND (arg_max, 0);
13435 /* If only one of the bounds used a MINUS_EXPR, compensate
13436 by adding one to the other bound. */
13437 if (parm_cst && !arg_cst)
13438 parm_max = fold_build2 (PLUS_EXPR,
13442 else if (arg_cst && !parm_cst)
13443 arg_max = fold_build2 (PLUS_EXPR,
13448 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
13451 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
13452 strict & UNIFY_ALLOW_MORE_CV_QUAL);
13459 case ENUMERAL_TYPE:
13461 if (TREE_CODE (arg) != TREE_CODE (parm))
13464 /* We have already checked cv-qualification at the top of the
13466 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
13469 /* As far as unification is concerned, this wins. Later checks
13470 will invalidate it if necessary. */
13473 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
13474 /* Type INTEGER_CST can come from ordinary constant template args. */
13476 while (TREE_CODE (arg) == NOP_EXPR)
13477 arg = TREE_OPERAND (arg, 0);
13479 if (TREE_CODE (arg) != INTEGER_CST)
13481 return !tree_int_cst_equal (parm, arg);
13486 if (TREE_CODE (arg) != TREE_VEC)
13488 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
13490 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
13491 if (unify (tparms, targs,
13492 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
13500 if (TREE_CODE (arg) != TREE_CODE (parm))
13503 if (TYPE_PTRMEMFUNC_P (parm))
13505 if (!TYPE_PTRMEMFUNC_P (arg))
13508 return unify (tparms, targs,
13509 TYPE_PTRMEMFUNC_FN_TYPE (parm),
13510 TYPE_PTRMEMFUNC_FN_TYPE (arg),
13514 if (CLASSTYPE_TEMPLATE_INFO (parm))
13516 tree t = NULL_TREE;
13518 if (strict_in & UNIFY_ALLOW_DERIVED)
13520 /* First, we try to unify the PARM and ARG directly. */
13521 t = try_class_unification (tparms, targs,
13526 /* Fallback to the special case allowed in
13527 [temp.deduct.call]:
13529 If P is a class, and P has the form
13530 template-id, then A can be a derived class of
13531 the deduced A. Likewise, if P is a pointer to
13532 a class of the form template-id, A can be a
13533 pointer to a derived class pointed to by the
13535 t = get_template_base (tparms, targs, parm, arg);
13541 else if (CLASSTYPE_TEMPLATE_INFO (arg)
13542 && (CLASSTYPE_TI_TEMPLATE (parm)
13543 == CLASSTYPE_TI_TEMPLATE (arg)))
13544 /* Perhaps PARM is something like S<U> and ARG is S<int>.
13545 Then, we should unify `int' and `U'. */
13548 /* There's no chance of unification succeeding. */
13551 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
13552 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
13554 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
13559 case FUNCTION_TYPE:
13560 if (TREE_CODE (arg) != TREE_CODE (parm))
13563 /* CV qualifications for methods can never be deduced, they must
13564 match exactly. We need to check them explicitly here,
13565 because type_unification_real treats them as any other
13566 cv-qualified parameter. */
13567 if (TREE_CODE (parm) == METHOD_TYPE
13568 && (!check_cv_quals_for_unify
13570 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
13571 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
13574 if (unify (tparms, targs, TREE_TYPE (parm),
13575 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
13577 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
13578 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
13582 /* Unify a pointer to member with a pointer to member function, which
13583 deduces the type of the member as a function type. */
13584 if (TYPE_PTRMEMFUNC_P (arg))
13588 cp_cv_quals cv_quals;
13590 /* Check top-level cv qualifiers */
13591 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
13594 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
13595 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
13598 /* Determine the type of the function we are unifying against. */
13599 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
13601 build_function_type (TREE_TYPE (method_type),
13602 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
13604 /* Extract the cv-qualifiers of the member function from the
13605 implicit object parameter and place them on the function
13606 type to be restored later. */
13608 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
13609 fntype = build_qualified_type (fntype, cv_quals);
13610 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
13613 if (TREE_CODE (arg) != OFFSET_TYPE)
13615 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
13616 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
13618 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
13622 if (DECL_TEMPLATE_PARM_P (parm))
13623 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
13624 if (arg != integral_constant_value (parm))
13629 case TEMPLATE_DECL:
13630 /* Matched cases are handled by the ARG == PARM test above. */
13633 case TYPE_ARGUMENT_PACK:
13634 case NONTYPE_ARGUMENT_PACK:
13636 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
13637 tree packed_args = ARGUMENT_PACK_ARGS (arg);
13638 int i, len = TREE_VEC_LENGTH (packed_parms);
13639 int argslen = TREE_VEC_LENGTH (packed_args);
13640 int parm_variadic_p = 0;
13642 for (i = 0; i < len; ++i)
13644 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
13647 /* We can unify against something with a trailing
13649 parm_variadic_p = 1;
13651 /* Since there is something following the pack
13652 expansion, we cannot unify this template argument
13659 /* If we don't have enough arguments to satisfy the parameters
13660 (not counting the pack expression at the end), or we have
13661 too many arguments for a parameter list that doesn't end in
13662 a pack expression, we can't unify. */
13663 if (argslen < (len - parm_variadic_p)
13664 || (argslen > len && !parm_variadic_p))
13667 /* Unify all of the parameters that precede the (optional)
13668 pack expression. */
13669 for (i = 0; i < len - parm_variadic_p; ++i)
13671 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
13672 TREE_VEC_ELT (packed_args, i), strict))
13676 if (parm_variadic_p)
13677 return unify_pack_expansion (tparms, targs,
13678 packed_parms, packed_args,
13679 strict, /*call_args_p=*/false,
13687 case DECLTYPE_TYPE:
13688 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
13693 /* Unification fails if we hit an error node. */
13697 gcc_assert (EXPR_P (parm));
13699 /* We must be looking at an expression. This can happen with
13703 void foo(S<I>, S<I + 2>);
13705 This is a "nondeduced context":
13709 The nondeduced contexts are:
13711 --A type that is a template-id in which one or more of
13712 the template-arguments is an expression that references
13713 a template-parameter.
13715 In these cases, we assume deduction succeeded, but don't
13716 actually infer any unifications. */
13718 if (!uses_template_parms (parm)
13719 && !template_args_equal (parm, arg))
13726 /* Note that DECL can be defined in this translation unit, if
13730 mark_definable (tree decl)
13733 DECL_NOT_REALLY_EXTERN (decl) = 1;
13734 FOR_EACH_CLONE (clone, decl)
13735 DECL_NOT_REALLY_EXTERN (clone) = 1;
13738 /* Called if RESULT is explicitly instantiated, or is a member of an
13739 explicitly instantiated class. */
13742 mark_decl_instantiated (tree result, int extern_p)
13744 SET_DECL_EXPLICIT_INSTANTIATION (result);
13746 /* If this entity has already been written out, it's too late to
13747 make any modifications. */
13748 if (TREE_ASM_WRITTEN (result))
13751 if (TREE_CODE (result) != FUNCTION_DECL)
13752 /* The TREE_PUBLIC flag for function declarations will have been
13753 set correctly by tsubst. */
13754 TREE_PUBLIC (result) = 1;
13756 /* This might have been set by an earlier implicit instantiation. */
13757 DECL_COMDAT (result) = 0;
13760 DECL_NOT_REALLY_EXTERN (result) = 0;
13763 mark_definable (result);
13764 /* Always make artificials weak. */
13765 if (DECL_ARTIFICIAL (result) && flag_weak)
13766 comdat_linkage (result);
13767 /* For WIN32 we also want to put explicit instantiations in
13768 linkonce sections. */
13769 else if (TREE_PUBLIC (result))
13770 maybe_make_one_only (result);
13773 /* If EXTERN_P, then this function will not be emitted -- unless
13774 followed by an explicit instantiation, at which point its linkage
13775 will be adjusted. If !EXTERN_P, then this function will be
13776 emitted here. In neither circumstance do we want
13777 import_export_decl to adjust the linkage. */
13778 DECL_INTERFACE_KNOWN (result) = 1;
13781 /* Given two function templates PAT1 and PAT2, return:
13783 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
13784 -1 if PAT2 is more specialized than PAT1.
13785 0 if neither is more specialized.
13787 LEN indicates the number of parameters we should consider
13788 (defaulted parameters should not be considered).
13790 The 1998 std underspecified function template partial ordering, and
13791 DR214 addresses the issue. We take pairs of arguments, one from
13792 each of the templates, and deduce them against each other. One of
13793 the templates will be more specialized if all the *other*
13794 template's arguments deduce against its arguments and at least one
13795 of its arguments *does* *not* deduce against the other template's
13796 corresponding argument. Deduction is done as for class templates.
13797 The arguments used in deduction have reference and top level cv
13798 qualifiers removed. Iff both arguments were originally reference
13799 types *and* deduction succeeds in both directions, the template
13800 with the more cv-qualified argument wins for that pairing (if
13801 neither is more cv-qualified, they both are equal). Unlike regular
13802 deduction, after all the arguments have been deduced in this way,
13803 we do *not* verify the deduced template argument values can be
13804 substituted into non-deduced contexts, nor do we have to verify
13805 that all template arguments have been deduced. */
13808 more_specialized_fn (tree pat1, tree pat2, int len)
13810 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
13811 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
13812 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
13813 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
13814 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
13815 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
13816 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
13817 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
13821 /* Remove the this parameter from non-static member functions. If
13822 one is a non-static member function and the other is not a static
13823 member function, remove the first parameter from that function
13824 also. This situation occurs for operator functions where we
13825 locate both a member function (with this pointer) and non-member
13826 operator (with explicit first operand). */
13827 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
13829 len--; /* LEN is the number of significant arguments for DECL1 */
13830 args1 = TREE_CHAIN (args1);
13831 if (!DECL_STATIC_FUNCTION_P (decl2))
13832 args2 = TREE_CHAIN (args2);
13834 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
13836 args2 = TREE_CHAIN (args2);
13837 if (!DECL_STATIC_FUNCTION_P (decl1))
13840 args1 = TREE_CHAIN (args1);
13844 /* If only one is a conversion operator, they are unordered. */
13845 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
13848 /* Consider the return type for a conversion function */
13849 if (DECL_CONV_FN_P (decl1))
13851 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
13852 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
13856 processing_template_decl++;
13859 /* Stop when an ellipsis is seen. */
13860 && args1 != NULL_TREE && args2 != NULL_TREE)
13862 tree arg1 = TREE_VALUE (args1);
13863 tree arg2 = TREE_VALUE (args2);
13864 int deduce1, deduce2;
13868 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
13869 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
13871 /* When both arguments are pack expansions, we need only
13872 unify the patterns themselves. */
13873 arg1 = PACK_EXPANSION_PATTERN (arg1);
13874 arg2 = PACK_EXPANSION_PATTERN (arg2);
13876 /* This is the last comparison we need to do. */
13880 if (TREE_CODE (arg1) == REFERENCE_TYPE)
13882 arg1 = TREE_TYPE (arg1);
13883 quals1 = cp_type_quals (arg1);
13886 if (TREE_CODE (arg2) == REFERENCE_TYPE)
13888 arg2 = TREE_TYPE (arg2);
13889 quals2 = cp_type_quals (arg2);
13892 if ((quals1 < 0) != (quals2 < 0))
13894 /* Only of the args is a reference, see if we should apply
13895 array/function pointer decay to it. This is not part of
13896 DR214, but is, IMHO, consistent with the deduction rules
13897 for the function call itself, and with our earlier
13898 implementation of the underspecified partial ordering
13899 rules. (nathan). */
13902 switch (TREE_CODE (arg1))
13905 arg1 = TREE_TYPE (arg1);
13907 case FUNCTION_TYPE:
13908 arg1 = build_pointer_type (arg1);
13917 switch (TREE_CODE (arg2))
13920 arg2 = TREE_TYPE (arg2);
13922 case FUNCTION_TYPE:
13923 arg2 = build_pointer_type (arg2);
13932 arg1 = TYPE_MAIN_VARIANT (arg1);
13933 arg2 = TYPE_MAIN_VARIANT (arg2);
13935 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
13937 int i, len2 = list_length (args2);
13938 tree parmvec = make_tree_vec (1);
13939 tree argvec = make_tree_vec (len2);
13942 /* Setup the parameter vector, which contains only ARG1. */
13943 TREE_VEC_ELT (parmvec, 0) = arg1;
13945 /* Setup the argument vector, which contains the remaining
13947 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
13948 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
13950 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
13951 argvec, UNIFY_ALLOW_NONE,
13952 /*call_args_p=*/false,
13955 /* We cannot deduce in the other direction, because ARG1 is
13956 a pack expansion but ARG2 is not. */
13959 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
13961 int i, len1 = list_length (args1);
13962 tree parmvec = make_tree_vec (1);
13963 tree argvec = make_tree_vec (len1);
13966 /* Setup the parameter vector, which contains only ARG1. */
13967 TREE_VEC_ELT (parmvec, 0) = arg2;
13969 /* Setup the argument vector, which contains the remaining
13971 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
13972 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
13974 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
13975 argvec, UNIFY_ALLOW_NONE,
13976 /*call_args_p=*/false,
13979 /* We cannot deduce in the other direction, because ARG2 is
13980 a pack expansion but ARG1 is not.*/
13986 /* The normal case, where neither argument is a pack
13988 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
13989 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
13996 if (better1 < 0 && better2 < 0)
13997 /* We've failed to deduce something in either direction.
13998 These must be unordered. */
14001 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
14003 /* Deduces in both directions, see if quals can
14004 disambiguate. Pretend the worse one failed to deduce. */
14005 if ((quals1 & quals2) == quals2)
14007 if ((quals1 & quals2) == quals1)
14010 if (deduce1 && !deduce2 && !better2)
14012 if (deduce2 && !deduce1 && !better1)
14015 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
14016 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
14017 /* We have already processed all of the arguments in our
14018 handing of the pack expansion type. */
14021 args1 = TREE_CHAIN (args1);
14022 args2 = TREE_CHAIN (args2);
14025 processing_template_decl--;
14027 /* All things being equal, if the next argument is a pack expansion
14028 for one function but not for the other, prefer the
14029 non-variadic function. */
14030 if ((better1 > 0) - (better2 > 0) == 0
14031 && args1 && TREE_VALUE (args1)
14032 && args2 && TREE_VALUE (args2))
14034 if (TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION)
14035 return TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION ? 0 : -1;
14036 else if (TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION)
14040 return (better1 > 0) - (better2 > 0);
14043 /* Determine which of two partial specializations is more specialized.
14045 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
14046 to the first partial specialization. The TREE_VALUE is the
14047 innermost set of template parameters for the partial
14048 specialization. PAT2 is similar, but for the second template.
14050 Return 1 if the first partial specialization is more specialized;
14051 -1 if the second is more specialized; 0 if neither is more
14054 See [temp.class.order] for information about determining which of
14055 two templates is more specialized. */
14058 more_specialized_class (tree pat1, tree pat2)
14063 bool any_deductions = false;
14065 tmpl1 = TREE_TYPE (pat1);
14066 tmpl2 = TREE_TYPE (pat2);
14068 /* Just like what happens for functions, if we are ordering between
14069 different class template specializations, we may encounter dependent
14070 types in the arguments, and we need our dependency check functions
14071 to behave correctly. */
14072 ++processing_template_decl;
14073 targs = get_class_bindings (TREE_VALUE (pat1),
14074 CLASSTYPE_TI_ARGS (tmpl1),
14075 CLASSTYPE_TI_ARGS (tmpl2));
14079 any_deductions = true;
14082 targs = get_class_bindings (TREE_VALUE (pat2),
14083 CLASSTYPE_TI_ARGS (tmpl2),
14084 CLASSTYPE_TI_ARGS (tmpl1));
14088 any_deductions = true;
14090 --processing_template_decl;
14092 /* In the case of a tie where at least one of the class templates
14093 has a parameter pack at the end, the template with the most
14094 non-packed parameters wins. */
14097 && (template_args_variadic_p (TREE_PURPOSE (pat1))
14098 || template_args_variadic_p (TREE_PURPOSE (pat2))))
14100 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
14101 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
14102 int len1 = TREE_VEC_LENGTH (args1);
14103 int len2 = TREE_VEC_LENGTH (args2);
14105 /* We don't count the pack expansion at the end. */
14106 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
14108 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
14113 else if (len1 < len2)
14120 /* Return the template arguments that will produce the function signature
14121 DECL from the function template FN, with the explicit template
14122 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
14123 also match. Return NULL_TREE if no satisfactory arguments could be
14127 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
14129 int ntparms = DECL_NTPARMS (fn);
14130 tree targs = make_tree_vec (ntparms);
14132 tree decl_arg_types;
14134 /* Substitute the explicit template arguments into the type of DECL.
14135 The call to fn_type_unification will handle substitution into the
14137 decl_type = TREE_TYPE (decl);
14138 if (explicit_args && uses_template_parms (decl_type))
14141 tree converted_args;
14143 if (DECL_TEMPLATE_INFO (decl))
14144 tmpl = DECL_TI_TEMPLATE (decl);
14146 /* We can get here for some invalid specializations. */
14150 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
14151 explicit_args, NULL_TREE,
14153 /*require_all_args=*/false,
14154 /*use_default_args=*/false);
14155 if (converted_args == error_mark_node)
14158 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
14159 if (decl_type == error_mark_node)
14163 /* Never do unification on the 'this' parameter. */
14164 decl_arg_types = skip_artificial_parms_for (decl,
14165 TYPE_ARG_TYPES (decl_type));
14167 if (fn_type_unification (fn, explicit_args, targs,
14169 (check_rettype || DECL_CONV_FN_P (fn)
14170 ? TREE_TYPE (decl_type) : NULL_TREE),
14171 DEDUCE_EXACT, LOOKUP_NORMAL))
14177 /* Return the innermost template arguments that, when applied to a
14178 template specialization whose innermost template parameters are
14179 TPARMS, and whose specialization arguments are PARMS, yield the
14182 For example, suppose we have:
14184 template <class T, class U> struct S {};
14185 template <class T> struct S<T*, int> {};
14187 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
14188 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
14189 int}. The resulting vector will be {double}, indicating that `T'
14190 is bound to `double'. */
14193 get_class_bindings (tree tparms, tree spec_args, tree args)
14195 int i, ntparms = TREE_VEC_LENGTH (tparms);
14197 tree innermost_deduced_args;
14199 innermost_deduced_args = make_tree_vec (ntparms);
14200 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
14202 deduced_args = copy_node (args);
14203 SET_TMPL_ARGS_LEVEL (deduced_args,
14204 TMPL_ARGS_DEPTH (deduced_args),
14205 innermost_deduced_args);
14208 deduced_args = innermost_deduced_args;
14210 if (unify (tparms, deduced_args,
14211 INNERMOST_TEMPLATE_ARGS (spec_args),
14212 INNERMOST_TEMPLATE_ARGS (args),
14216 for (i = 0; i < ntparms; ++i)
14217 if (! TREE_VEC_ELT (innermost_deduced_args, i))
14220 /* Verify that nondeduced template arguments agree with the type
14221 obtained from argument deduction.
14225 struct A { typedef int X; };
14226 template <class T, class U> struct C {};
14227 template <class T> struct C<T, typename T::X> {};
14229 Then with the instantiation `C<A, int>', we can deduce that
14230 `T' is `A' but unify () does not check whether `typename T::X'
14232 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
14233 if (spec_args == error_mark_node
14234 /* We only need to check the innermost arguments; the other
14235 arguments will always agree. */
14236 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
14237 INNERMOST_TEMPLATE_ARGS (args)))
14240 /* Now that we have bindings for all of the template arguments,
14241 ensure that the arguments deduced for the template template
14242 parameters have compatible template parameter lists. See the use
14243 of template_template_parm_bindings_ok_p in fn_type_unification
14244 for more information. */
14245 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
14248 return deduced_args;
14251 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
14252 Return the TREE_LIST node with the most specialized template, if
14253 any. If there is no most specialized template, the error_mark_node
14256 Note that this function does not look at, or modify, the
14257 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
14258 returned is one of the elements of INSTANTIATIONS, callers may
14259 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
14260 and retrieve it from the value returned. */
14263 most_specialized_instantiation (tree templates)
14267 ++processing_template_decl;
14270 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
14274 if (get_bindings (TREE_VALUE (champ),
14275 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
14276 NULL_TREE, /*check_ret=*/false))
14279 if (get_bindings (TREE_VALUE (fn),
14280 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
14281 NULL_TREE, /*check_ret=*/false))
14288 /* Equally specialized, move to next function. If there
14289 is no next function, nothing's most specialized. */
14290 fn = TREE_CHAIN (fn);
14298 /* Now verify that champ is better than everything earlier in the
14299 instantiation list. */
14300 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
14301 if (get_bindings (TREE_VALUE (champ),
14302 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
14303 NULL_TREE, /*check_ret=*/false)
14304 || !get_bindings (TREE_VALUE (fn),
14305 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
14306 NULL_TREE, /*check_ret=*/false))
14312 processing_template_decl--;
14315 return error_mark_node;
14320 /* If DECL is a specialization of some template, return the most
14321 general such template. Otherwise, returns NULL_TREE.
14323 For example, given:
14325 template <class T> struct S { template <class U> void f(U); };
14327 if TMPL is `template <class U> void S<int>::f(U)' this will return
14328 the full template. This function will not trace past partial
14329 specializations, however. For example, given in addition:
14331 template <class T> struct S<T*> { template <class U> void f(U); };
14333 if TMPL is `template <class U> void S<int*>::f(U)' this will return
14334 `template <class T> template <class U> S<T*>::f(U)'. */
14337 most_general_template (tree decl)
14339 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
14340 an immediate specialization. */
14341 if (TREE_CODE (decl) == FUNCTION_DECL)
14343 if (DECL_TEMPLATE_INFO (decl)) {
14344 decl = DECL_TI_TEMPLATE (decl);
14346 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
14347 template friend. */
14348 if (TREE_CODE (decl) != TEMPLATE_DECL)
14354 /* Look for more and more general templates. */
14355 while (DECL_TEMPLATE_INFO (decl))
14357 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
14358 (See cp-tree.h for details.) */
14359 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
14362 if (CLASS_TYPE_P (TREE_TYPE (decl))
14363 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
14366 /* Stop if we run into an explicitly specialized class template. */
14367 if (!DECL_NAMESPACE_SCOPE_P (decl)
14368 && DECL_CONTEXT (decl)
14369 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
14372 decl = DECL_TI_TEMPLATE (decl);
14378 /* Return the most specialized of the class template partial
14379 specializations of TMPL which can produce TYPE, a specialization of
14380 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
14381 a _TYPE node corresponding to the partial specialization, while the
14382 TREE_PURPOSE is the set of template arguments that must be
14383 substituted into the TREE_TYPE in order to generate TYPE.
14385 If the choice of partial specialization is ambiguous, a diagnostic
14386 is issued, and the error_mark_node is returned. If there are no
14387 partial specializations of TMPL matching TYPE, then NULL_TREE is
14391 most_specialized_class (tree type, tree tmpl)
14393 tree list = NULL_TREE;
14399 tree outer_args = NULL_TREE;
14401 tmpl = most_general_template (tmpl);
14402 args = CLASSTYPE_TI_ARGS (type);
14404 /* For determining which partial specialization to use, only the
14405 innermost args are interesting. */
14406 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
14408 outer_args = strip_innermost_template_args (args, 1);
14409 args = INNERMOST_TEMPLATE_ARGS (args);
14412 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
14414 tree partial_spec_args;
14416 tree parms = TREE_VALUE (t);
14418 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
14423 ++processing_template_decl;
14425 /* Discard the outer levels of args, and then substitute in the
14426 template args from the enclosing class. */
14427 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
14428 partial_spec_args = tsubst_template_args
14429 (partial_spec_args, outer_args, tf_none, NULL_TREE);
14431 /* PARMS already refers to just the innermost parms, but the
14432 template parms in partial_spec_args had their levels lowered
14433 by tsubst, so we need to do the same for the parm list. We
14434 can't just tsubst the TREE_VEC itself, as tsubst wants to
14435 treat a TREE_VEC as an argument vector. */
14436 parms = copy_node (parms);
14437 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
14438 TREE_VEC_ELT (parms, i) =
14439 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
14441 --processing_template_decl;
14443 spec_args = get_class_bindings (parms,
14449 spec_args = add_to_template_args (outer_args, spec_args);
14450 list = tree_cons (spec_args, TREE_VALUE (t), list);
14451 TREE_TYPE (list) = TREE_TYPE (t);
14458 ambiguous_p = false;
14461 t = TREE_CHAIN (t);
14462 for (; t; t = TREE_CHAIN (t))
14464 fate = more_specialized_class (champ, t);
14471 t = TREE_CHAIN (t);
14474 ambiguous_p = true;
14483 for (t = list; t && t != champ; t = TREE_CHAIN (t))
14485 fate = more_specialized_class (champ, t);
14488 ambiguous_p = true;
14495 const char *str = "candidates are:";
14496 error ("ambiguous class template instantiation for %q#T", type);
14497 for (t = list; t; t = TREE_CHAIN (t))
14499 error ("%s %+#T", str, TREE_TYPE (t));
14502 return error_mark_node;
14508 /* Explicitly instantiate DECL. */
14511 do_decl_instantiation (tree decl, tree storage)
14513 tree result = NULL_TREE;
14516 if (!decl || decl == error_mark_node)
14517 /* An error occurred, for which grokdeclarator has already issued
14518 an appropriate message. */
14520 else if (! DECL_LANG_SPECIFIC (decl))
14522 error ("explicit instantiation of non-template %q#D", decl);
14525 else if (TREE_CODE (decl) == VAR_DECL)
14527 /* There is an asymmetry here in the way VAR_DECLs and
14528 FUNCTION_DECLs are handled by grokdeclarator. In the case of
14529 the latter, the DECL we get back will be marked as a
14530 template instantiation, and the appropriate
14531 DECL_TEMPLATE_INFO will be set up. This does not happen for
14532 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
14533 should handle VAR_DECLs as it currently handles
14535 if (!DECL_CLASS_SCOPE_P (decl))
14537 error ("%qD is not a static data member of a class template", decl);
14540 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
14541 if (!result || TREE_CODE (result) != VAR_DECL)
14543 error ("no matching template for %qD found", decl);
14546 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
14548 error ("type %qT for explicit instantiation %qD does not match "
14549 "declared type %qT", TREE_TYPE (result), decl,
14554 else if (TREE_CODE (decl) != FUNCTION_DECL)
14556 error ("explicit instantiation of %q#D", decl);
14562 /* Check for various error cases. Note that if the explicit
14563 instantiation is valid the RESULT will currently be marked as an
14564 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
14565 until we get here. */
14567 if (DECL_TEMPLATE_SPECIALIZATION (result))
14569 /* DR 259 [temp.spec].
14571 Both an explicit instantiation and a declaration of an explicit
14572 specialization shall not appear in a program unless the explicit
14573 instantiation follows a declaration of the explicit specialization.
14575 For a given set of template parameters, if an explicit
14576 instantiation of a template appears after a declaration of an
14577 explicit specialization for that template, the explicit
14578 instantiation has no effect. */
14581 else if (DECL_EXPLICIT_INSTANTIATION (result))
14585 No program shall explicitly instantiate any template more
14588 We check DECL_NOT_REALLY_EXTERN so as not to complain when
14589 the first instantiation was `extern' and the second is not,
14590 and EXTERN_P for the opposite case. */
14591 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
14592 permerror ("duplicate explicit instantiation of %q#D", result);
14593 /* If an "extern" explicit instantiation follows an ordinary
14594 explicit instantiation, the template is instantiated. */
14598 else if (!DECL_IMPLICIT_INSTANTIATION (result))
14600 error ("no matching template for %qD found", result);
14603 else if (!DECL_TEMPLATE_INFO (result))
14605 permerror ("explicit instantiation of non-template %q#D", result);
14609 if (storage == NULL_TREE)
14611 else if (storage == ridpointers[(int) RID_EXTERN])
14613 if (pedantic && !in_system_header && (cxx_dialect == cxx98))
14614 pedwarn ("ISO C++ 1998 forbids the use of %<extern%> on explicit "
14619 error ("storage class %qD applied to template instantiation", storage);
14621 check_explicit_instantiation_namespace (result);
14622 mark_decl_instantiated (result, extern_p);
14624 instantiate_decl (result, /*defer_ok=*/1,
14625 /*expl_inst_class_mem_p=*/false);
14629 mark_class_instantiated (tree t, int extern_p)
14631 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
14632 SET_CLASSTYPE_INTERFACE_KNOWN (t);
14633 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
14634 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
14637 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
14638 rest_of_type_compilation (t, 1);
14642 /* Called from do_type_instantiation through binding_table_foreach to
14643 do recursive instantiation for the type bound in ENTRY. */
14645 bt_instantiate_type_proc (binding_entry entry, void *data)
14647 tree storage = *(tree *) data;
14649 if (MAYBE_CLASS_TYPE_P (entry->type)
14650 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
14651 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
14654 /* Called from do_type_instantiation to instantiate a member
14655 (a member function or a static member variable) of an
14656 explicitly instantiated class template. */
14658 instantiate_class_member (tree decl, int extern_p)
14660 mark_decl_instantiated (decl, extern_p);
14662 instantiate_decl (decl, /*defer_ok=*/1,
14663 /*expl_inst_class_mem_p=*/true);
14666 /* Perform an explicit instantiation of template class T. STORAGE, if
14667 non-null, is the RID for extern, inline or static. COMPLAIN is
14668 nonzero if this is called from the parser, zero if called recursively,
14669 since the standard is unclear (as detailed below). */
14672 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
14677 int previous_instantiation_extern_p = 0;
14679 if (TREE_CODE (t) == TYPE_DECL)
14682 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
14684 error ("explicit instantiation of non-template type %qT", t);
14690 if (!COMPLETE_TYPE_P (t))
14692 if (complain & tf_error)
14693 error ("explicit instantiation of %q#T before definition of template",
14698 if (storage != NULL_TREE)
14700 if (pedantic && !in_system_header)
14702 if (storage == ridpointers[(int) RID_EXTERN])
14704 if (cxx_dialect == cxx98)
14705 pedwarn("ISO C++ 1998 forbids the use of %<extern%> on "
14706 "explicit instantiations");
14709 pedwarn("ISO C++ forbids the use of %qE on explicit "
14710 "instantiations", storage);
14713 if (storage == ridpointers[(int) RID_INLINE])
14715 else if (storage == ridpointers[(int) RID_EXTERN])
14717 else if (storage == ridpointers[(int) RID_STATIC])
14721 error ("storage class %qD applied to template instantiation",
14727 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
14729 /* DR 259 [temp.spec].
14731 Both an explicit instantiation and a declaration of an explicit
14732 specialization shall not appear in a program unless the explicit
14733 instantiation follows a declaration of the explicit specialization.
14735 For a given set of template parameters, if an explicit
14736 instantiation of a template appears after a declaration of an
14737 explicit specialization for that template, the explicit
14738 instantiation has no effect. */
14741 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
14745 No program shall explicitly instantiate any template more
14748 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
14749 instantiation was `extern'. If EXTERN_P then the second is.
14750 These cases are OK. */
14751 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
14753 if (!previous_instantiation_extern_p && !extern_p
14754 && (complain & tf_error))
14755 permerror ("duplicate explicit instantiation of %q#T", t);
14757 /* If we've already instantiated the template, just return now. */
14758 if (!CLASSTYPE_INTERFACE_ONLY (t))
14762 check_explicit_instantiation_namespace (TYPE_NAME (t));
14763 mark_class_instantiated (t, extern_p);
14771 /* In contrast to implicit instantiation, where only the
14772 declarations, and not the definitions, of members are
14773 instantiated, we have here:
14777 The explicit instantiation of a class template specialization
14778 implies the instantiation of all of its members not
14779 previously explicitly specialized in the translation unit
14780 containing the explicit instantiation.
14782 Of course, we can't instantiate member template classes, since
14783 we don't have any arguments for them. Note that the standard
14784 is unclear on whether the instantiation of the members are
14785 *explicit* instantiations or not. However, the most natural
14786 interpretation is that it should be an explicit instantiation. */
14789 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
14790 if (TREE_CODE (tmp) == FUNCTION_DECL
14791 && DECL_TEMPLATE_INSTANTIATION (tmp))
14792 instantiate_class_member (tmp, extern_p);
14794 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
14795 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
14796 instantiate_class_member (tmp, extern_p);
14798 if (CLASSTYPE_NESTED_UTDS (t))
14799 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
14800 bt_instantiate_type_proc, &storage);
14804 /* Given a function DECL, which is a specialization of TMPL, modify
14805 DECL to be a re-instantiation of TMPL with the same template
14806 arguments. TMPL should be the template into which tsubst'ing
14807 should occur for DECL, not the most general template.
14809 One reason for doing this is a scenario like this:
14812 void f(const T&, int i);
14814 void g() { f(3, 7); }
14817 void f(const T& t, const int i) { }
14819 Note that when the template is first instantiated, with
14820 instantiate_template, the resulting DECL will have no name for the
14821 first parameter, and the wrong type for the second. So, when we go
14822 to instantiate the DECL, we regenerate it. */
14825 regenerate_decl_from_template (tree decl, tree tmpl)
14827 /* The arguments used to instantiate DECL, from the most general
14832 args = DECL_TI_ARGS (decl);
14833 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
14835 /* Make sure that we can see identifiers, and compute access
14837 push_access_scope (decl);
14839 if (TREE_CODE (decl) == FUNCTION_DECL)
14847 args_depth = TMPL_ARGS_DEPTH (args);
14848 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
14849 if (args_depth > parms_depth)
14850 args = get_innermost_template_args (args, parms_depth);
14852 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
14853 args, tf_error, NULL_TREE);
14855 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
14858 /* Merge parameter declarations. */
14859 decl_parm = skip_artificial_parms_for (decl,
14860 DECL_ARGUMENTS (decl));
14862 = skip_artificial_parms_for (code_pattern,
14863 DECL_ARGUMENTS (code_pattern));
14864 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
14869 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
14870 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
14871 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
14873 parm_type = type_decays_to (parm_type);
14874 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
14875 TREE_TYPE (decl_parm) = parm_type;
14876 attributes = DECL_ATTRIBUTES (pattern_parm);
14877 if (DECL_ATTRIBUTES (decl_parm) != attributes)
14879 DECL_ATTRIBUTES (decl_parm) = attributes;
14880 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
14882 decl_parm = TREE_CHAIN (decl_parm);
14883 pattern_parm = TREE_CHAIN (pattern_parm);
14885 /* Merge any parameters that match with the function parameter
14887 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
14890 tree expanded_types;
14891 /* Expand the TYPE_PACK_EXPANSION that provides the types for
14892 the parameters in this function parameter pack. */
14893 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
14894 args, tf_error, NULL_TREE);
14895 len = TREE_VEC_LENGTH (expanded_types);
14896 for (i = 0; i < len; i++)
14901 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
14902 /* Rename the parameter to include the index. */
14903 DECL_NAME (decl_parm) =
14904 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
14905 parm_type = TREE_VEC_ELT (expanded_types, i);
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);
14918 /* Merge additional specifiers from the CODE_PATTERN. */
14919 if (DECL_DECLARED_INLINE_P (code_pattern)
14920 && !DECL_DECLARED_INLINE_P (decl))
14921 DECL_DECLARED_INLINE_P (decl) = 1;
14922 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
14923 DECL_INLINE (decl) = 1;
14925 else if (TREE_CODE (decl) == VAR_DECL)
14926 DECL_INITIAL (decl) =
14927 tsubst_expr (DECL_INITIAL (code_pattern), args,
14928 tf_error, DECL_TI_TEMPLATE (decl),
14929 /*integral_constant_expression_p=*/false);
14931 gcc_unreachable ();
14933 pop_access_scope (decl);
14936 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
14937 substituted to get DECL. */
14940 template_for_substitution (tree decl)
14942 tree tmpl = DECL_TI_TEMPLATE (decl);
14944 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
14945 for the instantiation. This is not always the most general
14946 template. Consider, for example:
14949 struct S { template <class U> void f();
14950 template <> void f<int>(); };
14952 and an instantiation of S<double>::f<int>. We want TD to be the
14953 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
14954 while (/* An instantiation cannot have a definition, so we need a
14955 more general template. */
14956 DECL_TEMPLATE_INSTANTIATION (tmpl)
14957 /* We must also deal with friend templates. Given:
14959 template <class T> struct S {
14960 template <class U> friend void f() {};
14963 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
14964 so far as the language is concerned, but that's still
14965 where we get the pattern for the instantiation from. On
14966 other hand, if the definition comes outside the class, say:
14968 template <class T> struct S {
14969 template <class U> friend void f();
14971 template <class U> friend void f() {}
14973 we don't need to look any further. That's what the check for
14974 DECL_INITIAL is for. */
14975 || (TREE_CODE (decl) == FUNCTION_DECL
14976 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
14977 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
14979 /* The present template, TD, should not be a definition. If it
14980 were a definition, we should be using it! Note that we
14981 cannot restructure the loop to just keep going until we find
14982 a template with a definition, since that might go too far if
14983 a specialization was declared, but not defined. */
14984 gcc_assert (TREE_CODE (decl) != VAR_DECL
14985 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
14987 /* Fetch the more general template. */
14988 tmpl = DECL_TI_TEMPLATE (tmpl);
14994 /* Produce the definition of D, a _DECL generated from a template. If
14995 DEFER_OK is nonzero, then we don't have to actually do the
14996 instantiation now; we just have to do it sometime. Normally it is
14997 an error if this is an explicit instantiation but D is undefined.
14998 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
14999 explicitly instantiated class template. */
15002 instantiate_decl (tree d, int defer_ok,
15003 bool expl_inst_class_mem_p)
15005 tree tmpl = DECL_TI_TEMPLATE (d);
15012 bool pattern_defined;
15014 location_t saved_loc = input_location;
15017 /* This function should only be used to instantiate templates for
15018 functions and static member variables. */
15019 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
15020 || TREE_CODE (d) == VAR_DECL);
15022 /* Variables are never deferred; if instantiation is required, they
15023 are instantiated right away. That allows for better code in the
15024 case that an expression refers to the value of the variable --
15025 if the variable has a constant value the referring expression can
15026 take advantage of that fact. */
15027 if (TREE_CODE (d) == VAR_DECL)
15030 /* Don't instantiate cloned functions. Instead, instantiate the
15031 functions they cloned. */
15032 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
15033 d = DECL_CLONED_FUNCTION (d);
15035 if (DECL_TEMPLATE_INSTANTIATED (d))
15036 /* D has already been instantiated. It might seem reasonable to
15037 check whether or not D is an explicit instantiation, and, if so,
15038 stop here. But when an explicit instantiation is deferred
15039 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
15040 is set, even though we still need to do the instantiation. */
15043 /* If we already have a specialization of this declaration, then
15044 there's no reason to instantiate it. Note that
15045 retrieve_specialization gives us both instantiations and
15046 specializations, so we must explicitly check
15047 DECL_TEMPLATE_SPECIALIZATION. */
15048 gen_tmpl = most_general_template (tmpl);
15049 gen_args = DECL_TI_ARGS (d);
15050 spec = retrieve_specialization (gen_tmpl, gen_args,
15051 /*class_specializations_p=*/false);
15052 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
15055 /* This needs to happen before any tsubsting. */
15056 if (! push_tinst_level (d))
15059 timevar_push (TV_PARSE);
15061 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
15062 for the instantiation. */
15063 td = template_for_substitution (d);
15064 code_pattern = DECL_TEMPLATE_RESULT (td);
15066 /* We should never be trying to instantiate a member of a class
15067 template or partial specialization. */
15068 gcc_assert (d != code_pattern);
15070 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
15071 || DECL_TEMPLATE_SPECIALIZATION (td))
15072 /* In the case of a friend template whose definition is provided
15073 outside the class, we may have too many arguments. Drop the
15074 ones we don't need. The same is true for specializations. */
15075 args = get_innermost_template_args
15076 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
15080 if (TREE_CODE (d) == FUNCTION_DECL)
15081 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
15083 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
15085 /* We may be in the middle of deferred access check. Disable it now. */
15086 push_deferring_access_checks (dk_no_deferred);
15088 /* Unless an explicit instantiation directive has already determined
15089 the linkage of D, remember that a definition is available for
15091 if (pattern_defined
15092 && !DECL_INTERFACE_KNOWN (d)
15093 && !DECL_NOT_REALLY_EXTERN (d))
15094 mark_definable (d);
15096 input_location = DECL_SOURCE_LOCATION (d);
15098 /* If D is a member of an explicitly instantiated class template,
15099 and no definition is available, treat it like an implicit
15101 if (!pattern_defined && expl_inst_class_mem_p
15102 && DECL_EXPLICIT_INSTANTIATION (d))
15104 DECL_NOT_REALLY_EXTERN (d) = 0;
15105 DECL_INTERFACE_KNOWN (d) = 0;
15106 SET_DECL_IMPLICIT_INSTANTIATION (d);
15111 /* Recheck the substitutions to obtain any warning messages
15112 about ignoring cv qualifiers. */
15113 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
15114 tree type = TREE_TYPE (gen);
15116 /* Make sure that we can see identifiers, and compute access
15117 correctly. D is already the target FUNCTION_DECL with the
15119 push_access_scope (d);
15121 if (TREE_CODE (gen) == FUNCTION_DECL)
15123 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
15124 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
15126 /* Don't simply tsubst the function type, as that will give
15127 duplicate warnings about poor parameter qualifications.
15128 The function arguments are the same as the decl_arguments
15129 without the top level cv qualifiers. */
15130 type = TREE_TYPE (type);
15132 tsubst (type, gen_args, tf_warning_or_error, d);
15134 pop_access_scope (d);
15137 /* Check to see whether we know that this template will be
15138 instantiated in some other file, as with "extern template"
15140 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
15141 /* In general, we do not instantiate such templates... */
15143 /* ... but we instantiate inline functions so that we can inline
15145 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
15146 /* ... we instantiate static data members whose values are
15147 needed in integral constant expressions. */
15148 && ! (TREE_CODE (d) == VAR_DECL
15149 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
15151 /* Defer all other templates, unless we have been explicitly
15152 forbidden from doing so. */
15153 if (/* If there is no definition, we cannot instantiate the
15156 /* If it's OK to postpone instantiation, do so. */
15158 /* If this is a static data member that will be defined
15159 elsewhere, we don't want to instantiate the entire data
15160 member, but we do want to instantiate the initializer so that
15161 we can substitute that elsewhere. */
15162 || (external_p && TREE_CODE (d) == VAR_DECL))
15164 /* The definition of the static data member is now required so
15165 we must substitute the initializer. */
15166 if (TREE_CODE (d) == VAR_DECL
15167 && !DECL_INITIAL (d)
15168 && DECL_INITIAL (code_pattern))
15173 ns = decl_namespace_context (d);
15174 push_nested_namespace (ns);
15175 push_nested_class (DECL_CONTEXT (d));
15176 init = tsubst_expr (DECL_INITIAL (code_pattern),
15178 tf_warning_or_error, NULL_TREE,
15179 /*integral_constant_expression_p=*/false);
15180 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
15181 /*asmspec_tree=*/NULL_TREE,
15182 LOOKUP_ONLYCONVERTING);
15183 pop_nested_class ();
15184 pop_nested_namespace (ns);
15187 /* We restore the source position here because it's used by
15188 add_pending_template. */
15189 input_location = saved_loc;
15191 if (at_eof && !pattern_defined
15192 && DECL_EXPLICIT_INSTANTIATION (d))
15195 The definition of a non-exported function template, a
15196 non-exported member function template, or a non-exported
15197 member function or static data member of a class template
15198 shall be present in every translation unit in which it is
15199 explicitly instantiated. */
15201 ("explicit instantiation of %qD but no definition available", d);
15203 /* ??? Historically, we have instantiated inline functions, even
15204 when marked as "extern template". */
15205 if (!(external_p && TREE_CODE (d) == VAR_DECL))
15206 add_pending_template (d);
15209 /* Tell the repository that D is available in this translation unit
15210 -- and see if it is supposed to be instantiated here. */
15211 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
15213 /* In a PCH file, despite the fact that the repository hasn't
15214 requested instantiation in the PCH it is still possible that
15215 an instantiation will be required in a file that includes the
15218 add_pending_template (d);
15219 /* Instantiate inline functions so that the inliner can do its
15220 job, even though we'll not be emitting a copy of this
15222 if (!(TREE_CODE (d) == FUNCTION_DECL
15223 && flag_inline_trees
15224 && DECL_DECLARED_INLINE_P (d)))
15228 need_push = !cfun || !global_bindings_p ();
15230 push_to_top_level ();
15232 /* Mark D as instantiated so that recursive calls to
15233 instantiate_decl do not try to instantiate it again. */
15234 DECL_TEMPLATE_INSTANTIATED (d) = 1;
15236 /* Regenerate the declaration in case the template has been modified
15237 by a subsequent redeclaration. */
15238 regenerate_decl_from_template (d, td);
15240 /* We already set the file and line above. Reset them now in case
15241 they changed as a result of calling regenerate_decl_from_template. */
15242 input_location = DECL_SOURCE_LOCATION (d);
15244 if (TREE_CODE (d) == VAR_DECL)
15248 /* Clear out DECL_RTL; whatever was there before may not be right
15249 since we've reset the type of the declaration. */
15250 SET_DECL_RTL (d, NULL_RTX);
15251 DECL_IN_AGGR_P (d) = 0;
15253 /* The initializer is placed in DECL_INITIAL by
15254 regenerate_decl_from_template. Pull it out so that
15255 finish_decl can process it. */
15256 init = DECL_INITIAL (d);
15257 DECL_INITIAL (d) = NULL_TREE;
15258 DECL_INITIALIZED_P (d) = 0;
15260 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
15261 initializer. That function will defer actual emission until
15262 we have a chance to determine linkage. */
15263 DECL_EXTERNAL (d) = 0;
15265 /* Enter the scope of D so that access-checking works correctly. */
15266 push_nested_class (DECL_CONTEXT (d));
15267 finish_decl (d, init, NULL_TREE);
15268 pop_nested_class ();
15270 else if (TREE_CODE (d) == FUNCTION_DECL)
15272 htab_t saved_local_specializations;
15277 /* Save away the current list, in case we are instantiating one
15278 template from within the body of another. */
15279 saved_local_specializations = local_specializations;
15281 /* Set up the list of local specializations. */
15282 local_specializations = htab_create (37,
15283 hash_local_specialization,
15284 eq_local_specializations,
15287 /* Set up context. */
15288 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
15290 /* Create substitution entries for the parameters. */
15291 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
15292 tmpl_parm = DECL_ARGUMENTS (subst_decl);
15293 spec_parm = DECL_ARGUMENTS (d);
15294 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
15296 register_local_specialization (spec_parm, tmpl_parm);
15297 spec_parm = skip_artificial_parms_for (d, spec_parm);
15298 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
15300 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
15302 register_local_specialization (spec_parm, tmpl_parm);
15303 tmpl_parm = TREE_CHAIN (tmpl_parm);
15304 spec_parm = TREE_CHAIN (spec_parm);
15306 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
15308 /* Collect all of the extra "packed" parameters into an
15312 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
15313 tree argtypepack = make_node (TYPE_ARGUMENT_PACK);
15317 /* Count how many parameters remain. */
15318 for (t = spec_parm; t; t = TREE_CHAIN (t))
15321 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
15322 parmvec = make_tree_vec (len);
15323 parmtypevec = make_tree_vec (len);
15324 for(i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
15326 TREE_VEC_ELT (parmvec, i) = spec_parm;
15327 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
15330 /* Build the argument packs. */
15331 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
15332 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
15333 TREE_TYPE (argpack) = argtypepack;
15335 /* Register the (value) argument pack as a specialization of
15336 TMPL_PARM, then move on. */
15337 register_local_specialization (argpack, tmpl_parm);
15338 tmpl_parm = TREE_CHAIN (tmpl_parm);
15340 gcc_assert (!spec_parm);
15342 /* Substitute into the body of the function. */
15343 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
15344 tf_warning_or_error, tmpl,
15345 /*integral_constant_expression_p=*/false);
15347 /* Set the current input_location to the end of the function
15348 so that finish_function knows where we are. */
15349 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
15351 /* We don't need the local specializations any more. */
15352 htab_delete (local_specializations);
15353 local_specializations = saved_local_specializations;
15355 /* Finish the function. */
15356 d = finish_function (0);
15357 expand_or_defer_fn (d);
15360 /* We're not deferring instantiation any more. */
15361 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
15364 pop_from_top_level ();
15367 input_location = saved_loc;
15368 pop_deferring_access_checks ();
15369 pop_tinst_level ();
15371 timevar_pop (TV_PARSE);
15376 /* Run through the list of templates that we wish we could
15377 instantiate, and instantiate any we can. RETRIES is the
15378 number of times we retry pending template instantiation. */
15381 instantiate_pending_templates (int retries)
15384 location_t saved_loc = input_location;
15386 /* Instantiating templates may trigger vtable generation. This in turn
15387 may require further template instantiations. We place a limit here
15388 to avoid infinite loop. */
15389 if (pending_templates && retries >= max_tinst_depth)
15391 tree decl = pending_templates->tinst->decl;
15393 error ("template instantiation depth exceeds maximum of %d"
15394 " instantiating %q+D, possibly from virtual table generation"
15395 " (use -ftemplate-depth-NN to increase the maximum)",
15396 max_tinst_depth, decl);
15397 if (TREE_CODE (decl) == FUNCTION_DECL)
15398 /* Pretend that we defined it. */
15399 DECL_INITIAL (decl) = error_mark_node;
15405 struct pending_template **t = &pending_templates;
15406 struct pending_template *last = NULL;
15410 tree instantiation = reopen_tinst_level ((*t)->tinst);
15411 bool complete = false;
15413 if (TYPE_P (instantiation))
15417 if (!COMPLETE_TYPE_P (instantiation))
15419 instantiate_class_template (instantiation);
15420 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
15421 for (fn = TYPE_METHODS (instantiation);
15423 fn = TREE_CHAIN (fn))
15424 if (! DECL_ARTIFICIAL (fn))
15425 instantiate_decl (fn,
15427 /*expl_inst_class_mem_p=*/false);
15428 if (COMPLETE_TYPE_P (instantiation))
15432 complete = COMPLETE_TYPE_P (instantiation);
15436 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
15437 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
15440 = instantiate_decl (instantiation,
15442 /*expl_inst_class_mem_p=*/false);
15443 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
15447 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
15448 || DECL_TEMPLATE_INSTANTIATED (instantiation));
15452 /* If INSTANTIATION has been instantiated, then we don't
15453 need to consider it again in the future. */
15461 current_tinst_level = NULL;
15463 last_pending_template = last;
15465 while (reconsider);
15467 input_location = saved_loc;
15470 /* Substitute ARGVEC into T, which is a list of initializers for
15471 either base class or a non-static data member. The TREE_PURPOSEs
15472 are DECLs, and the TREE_VALUEs are the initializer values. Used by
15473 instantiate_decl. */
15476 tsubst_initializer_list (tree t, tree argvec)
15478 tree inits = NULL_TREE;
15480 for (; t; t = TREE_CHAIN (t))
15484 tree expanded_bases = NULL_TREE;
15485 tree expanded_arguments = NULL_TREE;
15488 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
15493 /* Expand the base class expansion type into separate base
15495 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
15496 tf_warning_or_error,
15498 if (expanded_bases == error_mark_node)
15501 /* We'll be building separate TREE_LISTs of arguments for
15503 len = TREE_VEC_LENGTH (expanded_bases);
15504 expanded_arguments = make_tree_vec (len);
15505 for (i = 0; i < len; i++)
15506 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
15508 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
15509 expand each argument in the TREE_VALUE of t. */
15510 expr = make_node (EXPR_PACK_EXPANSION);
15511 PACK_EXPANSION_PARAMETER_PACKS (expr) =
15512 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
15514 if (TREE_VALUE (t) == void_type_node)
15515 /* VOID_TYPE_NODE is used to indicate
15516 value-initialization. */
15518 for (i = 0; i < len; i++)
15519 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
15523 /* Substitute parameter packs into each argument in the
15525 in_base_initializer = 1;
15526 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
15528 tree expanded_exprs;
15530 /* Expand the argument. */
15531 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
15533 = tsubst_pack_expansion (expr, argvec,
15534 tf_warning_or_error,
15536 if (expanded_exprs == error_mark_node)
15539 /* Prepend each of the expanded expressions to the
15540 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
15541 for (i = 0; i < len; i++)
15543 TREE_VEC_ELT (expanded_arguments, i) =
15544 tree_cons (NULL_TREE,
15545 TREE_VEC_ELT (expanded_exprs, i),
15546 TREE_VEC_ELT (expanded_arguments, i));
15549 in_base_initializer = 0;
15551 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
15552 since we built them backwards. */
15553 for (i = 0; i < len; i++)
15555 TREE_VEC_ELT (expanded_arguments, i) =
15556 nreverse (TREE_VEC_ELT (expanded_arguments, i));
15561 for (i = 0; i < len; ++i)
15563 if (expanded_bases)
15565 decl = TREE_VEC_ELT (expanded_bases, i);
15566 decl = expand_member_init (decl);
15567 init = TREE_VEC_ELT (expanded_arguments, i);
15571 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
15572 tf_warning_or_error, NULL_TREE);
15574 decl = expand_member_init (decl);
15575 if (decl && !DECL_P (decl))
15576 in_base_initializer = 1;
15578 init = tsubst_expr (TREE_VALUE (t), argvec,
15579 tf_warning_or_error, NULL_TREE,
15580 /*integral_constant_expression_p=*/false);
15581 in_base_initializer = 0;
15586 init = build_tree_list (decl, init);
15587 TREE_CHAIN (init) = inits;
15595 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
15598 set_current_access_from_decl (tree decl)
15600 if (TREE_PRIVATE (decl))
15601 current_access_specifier = access_private_node;
15602 else if (TREE_PROTECTED (decl))
15603 current_access_specifier = access_protected_node;
15605 current_access_specifier = access_public_node;
15608 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
15609 is the instantiation (which should have been created with
15610 start_enum) and ARGS are the template arguments to use. */
15613 tsubst_enum (tree tag, tree newtag, tree args)
15617 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
15622 decl = TREE_VALUE (e);
15623 /* Note that in a template enum, the TREE_VALUE is the
15624 CONST_DECL, not the corresponding INTEGER_CST. */
15625 value = tsubst_expr (DECL_INITIAL (decl),
15626 args, tf_warning_or_error, NULL_TREE,
15627 /*integral_constant_expression_p=*/true);
15629 /* Give this enumeration constant the correct access. */
15630 set_current_access_from_decl (decl);
15632 /* Actually build the enumerator itself. */
15633 build_enumerator (DECL_NAME (decl), value, newtag);
15636 finish_enum (newtag);
15637 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
15638 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
15641 /* DECL is a FUNCTION_DECL that is a template specialization. Return
15642 its type -- but without substituting the innermost set of template
15643 arguments. So, innermost set of template parameters will appear in
15647 get_mostly_instantiated_function_type (tree decl)
15655 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
15656 targs = DECL_TI_ARGS (decl);
15657 tparms = DECL_TEMPLATE_PARMS (tmpl);
15658 parm_depth = TMPL_PARMS_DEPTH (tparms);
15660 /* There should be as many levels of arguments as there are levels
15662 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
15664 fn_type = TREE_TYPE (tmpl);
15666 if (parm_depth == 1)
15667 /* No substitution is necessary. */
15671 int i, save_access_control;
15674 /* Replace the innermost level of the TARGS with NULL_TREEs to
15675 let tsubst know not to substitute for those parameters. */
15676 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
15677 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
15678 SET_TMPL_ARGS_LEVEL (partial_args, i,
15679 TMPL_ARGS_LEVEL (targs, i));
15680 SET_TMPL_ARGS_LEVEL (partial_args,
15681 TMPL_ARGS_DEPTH (targs),
15682 make_tree_vec (DECL_NTPARMS (tmpl)));
15684 /* Disable access control as this function is used only during
15686 save_access_control = flag_access_control;
15687 flag_access_control = 0;
15689 ++processing_template_decl;
15690 /* Now, do the (partial) substitution to figure out the
15691 appropriate function type. */
15692 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
15693 --processing_template_decl;
15695 /* Substitute into the template parameters to obtain the real
15696 innermost set of parameters. This step is important if the
15697 innermost set of template parameters contains value
15698 parameters whose types depend on outer template parameters. */
15699 TREE_VEC_LENGTH (partial_args)--;
15700 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
15702 flag_access_control = save_access_control;
15708 /* Return truthvalue if we're processing a template different from
15709 the last one involved in diagnostics. */
15711 problematic_instantiation_changed (void)
15713 return last_template_error_tick != tinst_level_tick;
15716 /* Remember current template involved in diagnostics. */
15718 record_last_problematic_instantiation (void)
15720 last_template_error_tick = tinst_level_tick;
15723 struct tinst_level *
15724 current_instantiation (void)
15726 return current_tinst_level;
15729 /* [temp.param] Check that template non-type parm TYPE is of an allowable
15730 type. Return zero for ok, nonzero for disallowed. Issue error and
15731 warning messages under control of COMPLAIN. */
15734 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
15736 if (INTEGRAL_TYPE_P (type))
15738 else if (POINTER_TYPE_P (type))
15740 else if (TYPE_PTR_TO_MEMBER_P (type))
15742 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
15744 else if (TREE_CODE (type) == TYPENAME_TYPE)
15747 if (complain & tf_error)
15748 error ("%q#T is not a valid type for a template constant parameter", type);
15752 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
15753 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
15756 dependent_type_p_r (tree type)
15762 A type is dependent if it is:
15764 -- a template parameter. Template template parameters are types
15765 for us (since TYPE_P holds true for them) so we handle
15767 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
15768 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
15770 /* -- a qualified-id with a nested-name-specifier which contains a
15771 class-name that names a dependent type or whose unqualified-id
15772 names a dependent type. */
15773 if (TREE_CODE (type) == TYPENAME_TYPE)
15775 /* -- a cv-qualified type where the cv-unqualified type is
15777 type = TYPE_MAIN_VARIANT (type);
15778 /* -- a compound type constructed from any dependent type. */
15779 if (TYPE_PTR_TO_MEMBER_P (type))
15780 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
15781 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
15783 else if (TREE_CODE (type) == POINTER_TYPE
15784 || TREE_CODE (type) == REFERENCE_TYPE)
15785 return dependent_type_p (TREE_TYPE (type));
15786 else if (TREE_CODE (type) == FUNCTION_TYPE
15787 || TREE_CODE (type) == METHOD_TYPE)
15791 if (dependent_type_p (TREE_TYPE (type)))
15793 for (arg_type = TYPE_ARG_TYPES (type);
15795 arg_type = TREE_CHAIN (arg_type))
15796 if (dependent_type_p (TREE_VALUE (arg_type)))
15800 /* -- an array type constructed from any dependent type or whose
15801 size is specified by a constant expression that is
15802 value-dependent. */
15803 if (TREE_CODE (type) == ARRAY_TYPE)
15805 if (TYPE_DOMAIN (type)
15806 && dependent_type_p (TYPE_DOMAIN (type)))
15808 return dependent_type_p (TREE_TYPE (type));
15810 else if (TREE_CODE (type) == INTEGER_TYPE
15811 && !TREE_CONSTANT (TYPE_MAX_VALUE (type)))
15813 /* If this is the TYPE_DOMAIN of an array type, consider it
15815 return (value_dependent_expression_p (TYPE_MAX_VALUE (type))
15816 || type_dependent_expression_p (TYPE_MAX_VALUE (type)));
15819 /* -- a template-id in which either the template name is a template
15821 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
15823 /* ... or any of the template arguments is a dependent type or
15824 an expression that is type-dependent or value-dependent. */
15825 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
15826 && (any_dependent_template_arguments_p
15827 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
15830 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
15831 argument of the `typeof' expression is not type-dependent, then
15832 it should already been have resolved. */
15833 if (TREE_CODE (type) == TYPEOF_TYPE
15834 || TREE_CODE (type) == DECLTYPE_TYPE)
15837 /* A template argument pack is dependent if any of its packed
15839 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
15841 tree args = ARGUMENT_PACK_ARGS (type);
15842 int i, len = TREE_VEC_LENGTH (args);
15843 for (i = 0; i < len; ++i)
15844 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
15848 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
15849 be template parameters. */
15850 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
15853 /* The standard does not specifically mention types that are local
15854 to template functions or local classes, but they should be
15855 considered dependent too. For example:
15857 template <int I> void f() {
15862 The size of `E' cannot be known until the value of `I' has been
15863 determined. Therefore, `E' must be considered dependent. */
15864 scope = TYPE_CONTEXT (type);
15865 if (scope && TYPE_P (scope))
15866 return dependent_type_p (scope);
15867 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
15868 return type_dependent_expression_p (scope);
15870 /* Other types are non-dependent. */
15874 /* Returns TRUE if TYPE is dependent, in the sense of
15875 [temp.dep.type]. */
15878 dependent_type_p (tree type)
15880 /* If there are no template parameters in scope, then there can't be
15881 any dependent types. */
15882 if (!processing_template_decl)
15884 /* If we are not processing a template, then nobody should be
15885 providing us with a dependent type. */
15887 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM);
15891 /* If the type is NULL, we have not computed a type for the entity
15892 in question; in that case, the type is dependent. */
15896 /* Erroneous types can be considered non-dependent. */
15897 if (type == error_mark_node)
15900 /* If we have not already computed the appropriate value for TYPE,
15902 if (!TYPE_DEPENDENT_P_VALID (type))
15904 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
15905 TYPE_DEPENDENT_P_VALID (type) = 1;
15908 return TYPE_DEPENDENT_P (type);
15911 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
15914 dependent_scope_ref_p (tree expression, bool criterion (tree))
15919 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
15921 if (!TYPE_P (TREE_OPERAND (expression, 0)))
15924 scope = TREE_OPERAND (expression, 0);
15925 name = TREE_OPERAND (expression, 1);
15929 An id-expression is type-dependent if it contains a
15930 nested-name-specifier that contains a class-name that names a
15932 /* The suggested resolution to Core Issue 2 implies that if the
15933 qualifying type is the current class, then we must peek
15936 && currently_open_class (scope)
15937 && !criterion (name))
15939 if (dependent_type_p (scope))
15945 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
15946 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
15950 value_dependent_expression_p (tree expression)
15952 if (!processing_template_decl)
15955 /* A name declared with a dependent type. */
15956 if (DECL_P (expression) && type_dependent_expression_p (expression))
15959 switch (TREE_CODE (expression))
15961 case IDENTIFIER_NODE:
15962 /* A name that has not been looked up -- must be dependent. */
15965 case TEMPLATE_PARM_INDEX:
15966 /* A non-type template parm. */
15970 /* A non-type template parm. */
15971 if (DECL_TEMPLATE_PARM_P (expression))
15973 return value_dependent_expression_p (DECL_INITIAL (expression));
15976 /* A constant with integral or enumeration type and is initialized
15977 with an expression that is value-dependent. */
15978 if (DECL_INITIAL (expression)
15979 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
15980 && value_dependent_expression_p (DECL_INITIAL (expression)))
15984 case DYNAMIC_CAST_EXPR:
15985 case STATIC_CAST_EXPR:
15986 case CONST_CAST_EXPR:
15987 case REINTERPRET_CAST_EXPR:
15989 /* These expressions are value-dependent if the type to which
15990 the cast occurs is dependent or the expression being casted
15991 is value-dependent. */
15993 tree type = TREE_TYPE (expression);
15995 if (dependent_type_p (type))
15998 /* A functional cast has a list of operands. */
15999 expression = TREE_OPERAND (expression, 0);
16002 /* If there are no operands, it must be an expression such
16003 as "int()". This should not happen for aggregate types
16004 because it would form non-constant expressions. */
16005 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
16010 if (TREE_CODE (expression) == TREE_LIST)
16011 return any_value_dependent_elements_p (expression);
16013 return value_dependent_expression_p (expression);
16018 /* A `sizeof' expression is value-dependent if the operand is
16019 type-dependent or is a pack expansion. */
16020 expression = TREE_OPERAND (expression, 0);
16021 if (PACK_EXPANSION_P (expression))
16023 else if (TYPE_P (expression))
16024 return dependent_type_p (expression);
16025 return type_dependent_expression_p (expression);
16028 return dependent_scope_ref_p (expression, value_dependent_expression_p);
16030 case COMPONENT_REF:
16031 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
16032 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
16035 /* A CALL_EXPR may appear in a constant expression if it is a
16036 call to a builtin function, e.g., __builtin_constant_p. All
16037 such calls are value-dependent. */
16040 case NONTYPE_ARGUMENT_PACK:
16041 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
16042 is value-dependent. */
16044 tree values = ARGUMENT_PACK_ARGS (expression);
16045 int i, len = TREE_VEC_LENGTH (values);
16047 for (i = 0; i < len; ++i)
16048 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
16056 tree type2 = TRAIT_EXPR_TYPE2 (expression);
16057 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
16058 || (type2 ? dependent_type_p (type2) : false));
16062 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
16063 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
16066 /* A constant expression is value-dependent if any subexpression is
16067 value-dependent. */
16068 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
16070 case tcc_reference:
16072 return (value_dependent_expression_p
16073 (TREE_OPERAND (expression, 0)));
16075 case tcc_comparison:
16077 return ((value_dependent_expression_p
16078 (TREE_OPERAND (expression, 0)))
16079 || (value_dependent_expression_p
16080 (TREE_OPERAND (expression, 1))));
16082 case tcc_expression:
16086 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
16087 /* In some cases, some of the operands may be missing.
16088 (For example, in the case of PREDECREMENT_EXPR, the
16089 amount to increment by may be missing.) That doesn't
16090 make the expression dependent. */
16091 if (TREE_OPERAND (expression, i)
16092 && (value_dependent_expression_p
16093 (TREE_OPERAND (expression, i))))
16103 /* The expression is not value-dependent. */
16107 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
16108 [temp.dep.expr]. */
16111 type_dependent_expression_p (tree expression)
16113 if (!processing_template_decl)
16116 if (expression == error_mark_node)
16119 /* An unresolved name is always dependent. */
16120 if (TREE_CODE (expression) == IDENTIFIER_NODE
16121 || TREE_CODE (expression) == USING_DECL)
16124 /* Some expression forms are never type-dependent. */
16125 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
16126 || TREE_CODE (expression) == SIZEOF_EXPR
16127 || TREE_CODE (expression) == ALIGNOF_EXPR
16128 || TREE_CODE (expression) == TRAIT_EXPR
16129 || TREE_CODE (expression) == TYPEID_EXPR
16130 || TREE_CODE (expression) == DELETE_EXPR
16131 || TREE_CODE (expression) == VEC_DELETE_EXPR
16132 || TREE_CODE (expression) == THROW_EXPR)
16135 /* The types of these expressions depends only on the type to which
16136 the cast occurs. */
16137 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
16138 || TREE_CODE (expression) == STATIC_CAST_EXPR
16139 || TREE_CODE (expression) == CONST_CAST_EXPR
16140 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
16141 || TREE_CODE (expression) == CAST_EXPR)
16142 return dependent_type_p (TREE_TYPE (expression));
16144 /* The types of these expressions depends only on the type created
16145 by the expression. */
16146 if (TREE_CODE (expression) == NEW_EXPR
16147 || TREE_CODE (expression) == VEC_NEW_EXPR)
16149 /* For NEW_EXPR tree nodes created inside a template, either
16150 the object type itself or a TREE_LIST may appear as the
16152 tree type = TREE_OPERAND (expression, 1);
16153 if (TREE_CODE (type) == TREE_LIST)
16154 /* This is an array type. We need to check array dimensions
16156 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
16157 || value_dependent_expression_p
16158 (TREE_OPERAND (TREE_VALUE (type), 1));
16160 return dependent_type_p (type);
16163 if (TREE_CODE (expression) == SCOPE_REF
16164 && dependent_scope_ref_p (expression,
16165 type_dependent_expression_p))
16168 if (TREE_CODE (expression) == FUNCTION_DECL
16169 && DECL_LANG_SPECIFIC (expression)
16170 && DECL_TEMPLATE_INFO (expression)
16171 && (any_dependent_template_arguments_p
16172 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
16175 if (TREE_CODE (expression) == TEMPLATE_DECL
16176 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
16179 if (TREE_CODE (expression) == STMT_EXPR)
16180 expression = stmt_expr_value_expr (expression);
16182 if (TREE_TYPE (expression) == unknown_type_node)
16184 if (TREE_CODE (expression) == ADDR_EXPR)
16185 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
16186 if (TREE_CODE (expression) == COMPONENT_REF
16187 || TREE_CODE (expression) == OFFSET_REF)
16189 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
16191 expression = TREE_OPERAND (expression, 1);
16192 if (TREE_CODE (expression) == IDENTIFIER_NODE)
16195 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
16196 if (TREE_CODE (expression) == SCOPE_REF)
16199 if (TREE_CODE (expression) == BASELINK)
16200 expression = BASELINK_FUNCTIONS (expression);
16202 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
16204 if (any_dependent_template_arguments_p
16205 (TREE_OPERAND (expression, 1)))
16207 expression = TREE_OPERAND (expression, 0);
16209 gcc_assert (TREE_CODE (expression) == OVERLOAD
16210 || TREE_CODE (expression) == FUNCTION_DECL);
16214 if (type_dependent_expression_p (OVL_CURRENT (expression)))
16216 expression = OVL_NEXT (expression);
16221 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
16223 return (dependent_type_p (TREE_TYPE (expression)));
16226 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
16227 contains a type-dependent expression. */
16230 any_type_dependent_arguments_p (const_tree args)
16234 tree arg = TREE_VALUE (args);
16236 if (type_dependent_expression_p (arg))
16238 args = TREE_CHAIN (args);
16243 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
16244 expressions) contains any value-dependent expressions. */
16247 any_value_dependent_elements_p (const_tree list)
16249 for (; list; list = TREE_CHAIN (list))
16250 if (value_dependent_expression_p (TREE_VALUE (list)))
16256 /* Returns TRUE if the ARG (a template argument) is dependent. */
16259 dependent_template_arg_p (tree arg)
16261 if (!processing_template_decl)
16264 if (TREE_CODE (arg) == TEMPLATE_DECL
16265 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
16266 return dependent_template_p (arg);
16267 else if (ARGUMENT_PACK_P (arg))
16269 tree args = ARGUMENT_PACK_ARGS (arg);
16270 int i, len = TREE_VEC_LENGTH (args);
16271 for (i = 0; i < len; ++i)
16273 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
16279 else if (TYPE_P (arg))
16280 return dependent_type_p (arg);
16282 return (type_dependent_expression_p (arg)
16283 || value_dependent_expression_p (arg));
16286 /* Returns true if ARGS (a collection of template arguments) contains
16287 any types that require structural equality testing. */
16290 any_template_arguments_need_structural_equality_p (tree args)
16297 if (args == error_mark_node)
16300 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
16302 tree level = TMPL_ARGS_LEVEL (args, i + 1);
16303 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
16305 tree arg = TREE_VEC_ELT (level, j);
16306 tree packed_args = NULL_TREE;
16309 if (ARGUMENT_PACK_P (arg))
16311 /* Look inside the argument pack. */
16312 packed_args = ARGUMENT_PACK_ARGS (arg);
16313 len = TREE_VEC_LENGTH (packed_args);
16316 for (k = 0; k < len; ++k)
16319 arg = TREE_VEC_ELT (packed_args, k);
16321 if (error_operand_p (arg))
16323 else if (TREE_CODE (arg) == TEMPLATE_DECL
16324 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
16326 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
16328 else if (!TYPE_P (arg) && TREE_TYPE (arg)
16329 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
16338 /* Returns true if ARGS (a collection of template arguments) contains
16339 any dependent arguments. */
16342 any_dependent_template_arguments_p (const_tree args)
16349 if (args == error_mark_node)
16352 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
16354 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
16355 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
16356 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
16363 /* Returns TRUE if the template TMPL is dependent. */
16366 dependent_template_p (tree tmpl)
16368 if (TREE_CODE (tmpl) == OVERLOAD)
16372 if (dependent_template_p (OVL_FUNCTION (tmpl)))
16374 tmpl = OVL_CHAIN (tmpl);
16379 /* Template template parameters are dependent. */
16380 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
16381 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
16383 /* So are names that have not been looked up. */
16384 if (TREE_CODE (tmpl) == SCOPE_REF
16385 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
16387 /* So are member templates of dependent classes. */
16388 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
16389 return dependent_type_p (DECL_CONTEXT (tmpl));
16393 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
16396 dependent_template_id_p (tree tmpl, tree args)
16398 return (dependent_template_p (tmpl)
16399 || any_dependent_template_arguments_p (args));
16402 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
16406 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
16410 if (!processing_template_decl)
16413 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
16415 tree decl = TREE_VEC_ELT (declv, i);
16416 tree init = TREE_VEC_ELT (initv, i);
16417 tree cond = TREE_VEC_ELT (condv, i);
16418 tree incr = TREE_VEC_ELT (incrv, i);
16420 if (type_dependent_expression_p (decl))
16423 if (init && type_dependent_expression_p (init))
16426 if (type_dependent_expression_p (cond))
16429 if (COMPARISON_CLASS_P (cond)
16430 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
16431 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
16434 if (TREE_CODE (incr) == MODOP_EXPR)
16436 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
16437 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
16440 else if (type_dependent_expression_p (incr))
16442 else if (TREE_CODE (incr) == MODIFY_EXPR)
16444 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
16446 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
16448 tree t = TREE_OPERAND (incr, 1);
16449 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
16450 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
16459 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
16460 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
16461 no such TYPE can be found. Note that this function peers inside
16462 uninstantiated templates and therefore should be used only in
16463 extremely limited situations. ONLY_CURRENT_P restricts this
16464 peering to the currently open classes hierarchy (which is required
16465 when comparing types). */
16468 resolve_typename_type (tree type, bool only_current_p)
16477 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
16479 scope = TYPE_CONTEXT (type);
16480 name = TYPE_IDENTIFIER (type);
16482 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
16483 it first before we can figure out what NAME refers to. */
16484 if (TREE_CODE (scope) == TYPENAME_TYPE)
16485 scope = resolve_typename_type (scope, only_current_p);
16486 /* If we don't know what SCOPE refers to, then we cannot resolve the
16488 if (TREE_CODE (scope) == TYPENAME_TYPE)
16490 /* If the SCOPE is a template type parameter, we have no way of
16491 resolving the name. */
16492 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
16494 /* If the SCOPE is not the current instantiation, there's no reason
16495 to look inside it. */
16496 if (only_current_p && !currently_open_class (scope))
16498 /* If SCOPE isn't the template itself, it will not have a valid
16499 TYPE_FIELDS list. */
16500 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
16501 /* scope is either the template itself or a compatible instantiation
16502 like X<T>, so look up the name in the original template. */
16503 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
16505 /* scope is a partial instantiation, so we can't do the lookup or we
16506 will lose the template arguments. */
16508 /* Enter the SCOPE so that name lookup will be resolved as if we
16509 were in the class definition. In particular, SCOPE will no
16510 longer be considered a dependent type. */
16511 pushed_scope = push_scope (scope);
16512 /* Look up the declaration. */
16513 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
16515 result = NULL_TREE;
16517 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
16518 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
16521 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
16522 && TREE_CODE (decl) == TYPE_DECL)
16524 result = TREE_TYPE (decl);
16525 if (result == error_mark_node)
16526 result = NULL_TREE;
16528 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
16529 && DECL_CLASS_TEMPLATE_P (decl))
16533 /* Obtain the template and the arguments. */
16534 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
16535 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
16536 /* Instantiate the template. */
16537 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
16538 /*entering_scope=*/0,
16539 tf_error | tf_user);
16540 if (result == error_mark_node)
16541 result = NULL_TREE;
16544 /* Leave the SCOPE. */
16546 pop_scope (pushed_scope);
16548 /* If we failed to resolve it, return the original typename. */
16552 /* If lookup found a typename type, resolve that too. */
16553 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
16555 /* Ill-formed programs can cause infinite recursion here, so we
16556 must catch that. */
16557 TYPENAME_IS_RESOLVING_P (type) = 1;
16558 result = resolve_typename_type (result, only_current_p);
16559 TYPENAME_IS_RESOLVING_P (type) = 0;
16562 /* Qualify the resulting type. */
16563 quals = cp_type_quals (type);
16565 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
16570 /* EXPR is an expression which is not type-dependent. Return a proxy
16571 for EXPR that can be used to compute the types of larger
16572 expressions containing EXPR. */
16575 build_non_dependent_expr (tree expr)
16579 /* Preserve null pointer constants so that the type of things like
16580 "p == 0" where "p" is a pointer can be determined. */
16581 if (null_ptr_cst_p (expr))
16583 /* Preserve OVERLOADs; the functions must be available to resolve
16586 if (TREE_CODE (inner_expr) == STMT_EXPR)
16587 inner_expr = stmt_expr_value_expr (inner_expr);
16588 if (TREE_CODE (inner_expr) == ADDR_EXPR)
16589 inner_expr = TREE_OPERAND (inner_expr, 0);
16590 if (TREE_CODE (inner_expr) == COMPONENT_REF)
16591 inner_expr = TREE_OPERAND (inner_expr, 1);
16592 if (is_overloaded_fn (inner_expr)
16593 || TREE_CODE (inner_expr) == OFFSET_REF)
16595 /* There is no need to return a proxy for a variable. */
16596 if (TREE_CODE (expr) == VAR_DECL)
16598 /* Preserve string constants; conversions from string constants to
16599 "char *" are allowed, even though normally a "const char *"
16600 cannot be used to initialize a "char *". */
16601 if (TREE_CODE (expr) == STRING_CST)
16603 /* Preserve arithmetic constants, as an optimization -- there is no
16604 reason to create a new node. */
16605 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
16607 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
16608 There is at least one place where we want to know that a
16609 particular expression is a throw-expression: when checking a ?:
16610 expression, there are special rules if the second or third
16611 argument is a throw-expression. */
16612 if (TREE_CODE (expr) == THROW_EXPR)
16615 if (TREE_CODE (expr) == COND_EXPR)
16616 return build3 (COND_EXPR,
16618 TREE_OPERAND (expr, 0),
16619 (TREE_OPERAND (expr, 1)
16620 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
16621 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
16622 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
16623 if (TREE_CODE (expr) == COMPOUND_EXPR
16624 && !COMPOUND_EXPR_OVERLOADED (expr))
16625 return build2 (COMPOUND_EXPR,
16627 TREE_OPERAND (expr, 0),
16628 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
16630 /* If the type is unknown, it can't really be non-dependent */
16631 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
16633 /* Otherwise, build a NON_DEPENDENT_EXPR.
16635 REFERENCE_TYPEs are not stripped for expressions in templates
16636 because doing so would play havoc with mangling. Consider, for
16639 template <typename T> void f<T& g>() { g(); }
16641 In the body of "f", the expression for "g" will have
16642 REFERENCE_TYPE, even though the standard says that it should
16643 not. The reason is that we must preserve the syntactic form of
16644 the expression so that mangling (say) "f<g>" inside the body of
16645 "f" works out correctly. Therefore, the REFERENCE_TYPE is
16647 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
16650 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
16651 Return a new TREE_LIST with the various arguments replaced with
16652 equivalent non-dependent expressions. */
16655 build_non_dependent_args (tree args)
16660 new_args = NULL_TREE;
16661 for (a = args; a; a = TREE_CHAIN (a))
16662 new_args = tree_cons (NULL_TREE,
16663 build_non_dependent_expr (TREE_VALUE (a)),
16665 return nreverse (new_args);
16668 #include "gt-cp-pt.h"