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)
1292 DECL_DECLARED_INLINE_P (clone)
1293 = DECL_DECLARED_INLINE_P (fn);
1294 check_specialization_namespace (fn);
1299 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1301 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1302 /* Dup decl failed, but this is a new definition. Set the
1303 line number so any errors match this new
1305 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1311 /* A specialization must be declared in the same namespace as the
1312 template it is specializing. */
1313 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1314 && !check_specialization_namespace (tmpl))
1315 DECL_CONTEXT (spec) = FROB_CONTEXT (decl_namespace_context (tmpl));
1317 if (!optimize_specialization_lookup_p (tmpl))
1318 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1319 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1324 /* Unregister the specialization SPEC as a specialization of TMPL.
1325 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1326 if the SPEC was listed as a specialization of TMPL. */
1329 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1333 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1335 s = &TREE_CHAIN (*s))
1336 if (TREE_VALUE (*s) == spec)
1339 *s = TREE_CHAIN (*s);
1341 TREE_VALUE (*s) = new_spec;
1348 /* Compare an entry in the local specializations hash table P1 (which
1349 is really a pointer to a TREE_LIST) with P2 (which is really a
1353 eq_local_specializations (const void *p1, const void *p2)
1355 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1358 /* Hash P1, an entry in the local specializations table. */
1361 hash_local_specialization (const void* p1)
1363 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1366 /* Like register_specialization, but for local declarations. We are
1367 registering SPEC, an instantiation of TMPL. */
1370 register_local_specialization (tree spec, tree tmpl)
1374 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1375 htab_hash_pointer (tmpl), INSERT);
1376 *slot = build_tree_list (spec, tmpl);
1379 /* TYPE is a class type. Returns true if TYPE is an explicitly
1380 specialized class. */
1383 explicit_class_specialization_p (tree type)
1385 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1387 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1390 /* Print the list of candidate FNS in an error message. */
1393 print_candidates (tree fns)
1397 const char *str = "candidates are:";
1399 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1403 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1404 error ("%s %+#D", str, OVL_CURRENT (f));
1409 /* Returns the template (one of the functions given by TEMPLATE_ID)
1410 which can be specialized to match the indicated DECL with the
1411 explicit template args given in TEMPLATE_ID. The DECL may be
1412 NULL_TREE if none is available. In that case, the functions in
1413 TEMPLATE_ID are non-members.
1415 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1416 specialization of a member template.
1418 The TEMPLATE_COUNT is the number of references to qualifying
1419 template classes that appeared in the name of the function. See
1420 check_explicit_specialization for a more accurate description.
1422 TSK indicates what kind of template declaration (if any) is being
1423 declared. TSK_TEMPLATE indicates that the declaration given by
1424 DECL, though a FUNCTION_DECL, has template parameters, and is
1425 therefore a template function.
1427 The template args (those explicitly specified and those deduced)
1428 are output in a newly created vector *TARGS_OUT.
1430 If it is impossible to determine the result, an error message is
1431 issued. The error_mark_node is returned to indicate failure. */
1434 determine_specialization (tree template_id,
1437 int need_member_template,
1443 tree explicit_targs;
1444 tree candidates = NULL_TREE;
1445 /* A TREE_LIST of templates of which DECL may be a specialization.
1446 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1447 corresponding TREE_PURPOSE is the set of template arguments that,
1448 when used to instantiate the template, would produce a function
1449 with the signature of DECL. */
1450 tree templates = NULL_TREE;
1452 struct cp_binding_level *b;
1454 *targs_out = NULL_TREE;
1456 if (template_id == error_mark_node || decl == error_mark_node)
1457 return error_mark_node;
1459 fns = TREE_OPERAND (template_id, 0);
1460 explicit_targs = TREE_OPERAND (template_id, 1);
1462 if (fns == error_mark_node)
1463 return error_mark_node;
1465 /* Check for baselinks. */
1466 if (BASELINK_P (fns))
1467 fns = BASELINK_FUNCTIONS (fns);
1469 if (!is_overloaded_fn (fns))
1471 error ("%qD is not a function template", fns);
1472 return error_mark_node;
1475 /* Count the number of template headers specified for this
1478 for (b = current_binding_level;
1479 b->kind == sk_template_parms;
1483 for (; fns; fns = OVL_NEXT (fns))
1485 tree fn = OVL_CURRENT (fns);
1487 if (TREE_CODE (fn) == TEMPLATE_DECL)
1489 tree decl_arg_types;
1492 /* In case of explicit specialization, we need to check if
1493 the number of template headers appearing in the specialization
1494 is correct. This is usually done in check_explicit_specialization,
1495 but the check done there cannot be exhaustive when specializing
1496 member functions. Consider the following code:
1498 template <> void A<int>::f(int);
1499 template <> template <> void A<int>::f(int);
1501 Assuming that A<int> is not itself an explicit specialization
1502 already, the first line specializes "f" which is a non-template
1503 member function, whilst the second line specializes "f" which
1504 is a template member function. So both lines are syntactically
1505 correct, and check_explicit_specialization does not reject
1508 Here, we can do better, as we are matching the specialization
1509 against the declarations. We count the number of template
1510 headers, and we check if they match TEMPLATE_COUNT + 1
1511 (TEMPLATE_COUNT is the number of qualifying template classes,
1512 plus there must be another header for the member template
1515 Notice that if header_count is zero, this is not a
1516 specialization but rather a template instantiation, so there
1517 is no check we can perform here. */
1518 if (header_count && header_count != template_count + 1)
1521 /* Check that the number of template arguments at the
1522 innermost level for DECL is the same as for FN. */
1523 if (current_binding_level->kind == sk_template_parms
1524 && !current_binding_level->explicit_spec_p
1525 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1526 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1527 (current_template_parms))))
1530 /* DECL might be a specialization of FN. */
1531 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1532 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1534 /* For a non-static member function, we need to make sure
1535 that the const qualification is the same. Since
1536 get_bindings does not try to merge the "this" parameter,
1537 we must do the comparison explicitly. */
1538 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1539 && !same_type_p (TREE_VALUE (fn_arg_types),
1540 TREE_VALUE (decl_arg_types)))
1543 /* Skip the "this" parameter and, for constructors of
1544 classes with virtual bases, the VTT parameter. A
1545 full specialization of a constructor will have a VTT
1546 parameter, but a template never will. */
1548 = skip_artificial_parms_for (decl, decl_arg_types);
1550 = skip_artificial_parms_for (fn, fn_arg_types);
1552 /* Check that the number of function parameters matches.
1554 template <class T> void f(int i = 0);
1555 template <> void f<int>();
1556 The specialization f<int> is invalid but is not caught
1557 by get_bindings below. */
1558 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1561 /* Function templates cannot be specializations; there are
1562 no partial specializations of functions. Therefore, if
1563 the type of DECL does not match FN, there is no
1565 if (tsk == tsk_template)
1567 if (compparms (fn_arg_types, decl_arg_types))
1568 candidates = tree_cons (NULL_TREE, fn, candidates);
1572 /* See whether this function might be a specialization of this
1574 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1577 /* We cannot deduce template arguments that when used to
1578 specialize TMPL will produce DECL. */
1581 /* Save this template, and the arguments deduced. */
1582 templates = tree_cons (targs, fn, templates);
1584 else if (need_member_template)
1585 /* FN is an ordinary member function, and we need a
1586 specialization of a member template. */
1588 else if (TREE_CODE (fn) != FUNCTION_DECL)
1589 /* We can get IDENTIFIER_NODEs here in certain erroneous
1592 else if (!DECL_FUNCTION_MEMBER_P (fn))
1593 /* This is just an ordinary non-member function. Nothing can
1594 be a specialization of that. */
1596 else if (DECL_ARTIFICIAL (fn))
1597 /* Cannot specialize functions that are created implicitly. */
1601 tree decl_arg_types;
1603 /* This is an ordinary member function. However, since
1604 we're here, we can assume it's enclosing class is a
1605 template class. For example,
1607 template <typename T> struct S { void f(); };
1608 template <> void S<int>::f() {}
1610 Here, S<int>::f is a non-template, but S<int> is a
1611 template class. If FN has the same type as DECL, we
1612 might be in business. */
1614 if (!DECL_TEMPLATE_INFO (fn))
1615 /* Its enclosing class is an explicit specialization
1616 of a template class. This is not a candidate. */
1619 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1620 TREE_TYPE (TREE_TYPE (fn))))
1621 /* The return types differ. */
1624 /* Adjust the type of DECL in case FN is a static member. */
1625 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1626 if (DECL_STATIC_FUNCTION_P (fn)
1627 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1628 decl_arg_types = TREE_CHAIN (decl_arg_types);
1630 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1633 candidates = tree_cons (NULL_TREE, fn, candidates);
1637 if (templates && TREE_CHAIN (templates))
1643 It is possible for a specialization with a given function
1644 signature to be instantiated from more than one function
1645 template. In such cases, explicit specification of the
1646 template arguments must be used to uniquely identify the
1647 function template specialization being specialized.
1649 Note that here, there's no suggestion that we're supposed to
1650 determine which of the candidate templates is most
1651 specialized. However, we, also have:
1655 Partial ordering of overloaded function template
1656 declarations is used in the following contexts to select
1657 the function template to which a function template
1658 specialization refers:
1660 -- when an explicit specialization refers to a function
1663 So, we do use the partial ordering rules, at least for now.
1664 This extension can only serve to make invalid programs valid,
1665 so it's safe. And, there is strong anecdotal evidence that
1666 the committee intended the partial ordering rules to apply;
1667 the EDG front end has that behavior, and John Spicer claims
1668 that the committee simply forgot to delete the wording in
1669 [temp.expl.spec]. */
1670 tree tmpl = most_specialized_instantiation (templates);
1671 if (tmpl != error_mark_node)
1674 TREE_CHAIN (templates) = NULL_TREE;
1678 if (templates == NULL_TREE && candidates == NULL_TREE)
1680 error ("template-id %qD for %q+D does not match any template "
1681 "declaration", template_id, decl);
1682 return error_mark_node;
1684 else if ((templates && TREE_CHAIN (templates))
1685 || (candidates && TREE_CHAIN (candidates))
1686 || (templates && candidates))
1688 error ("ambiguous template specialization %qD for %q+D",
1690 chainon (candidates, templates);
1691 print_candidates (candidates);
1692 return error_mark_node;
1695 /* We have one, and exactly one, match. */
1698 tree fn = TREE_VALUE (candidates);
1699 /* DECL is a re-declaration of a template function. */
1700 if (TREE_CODE (fn) == TEMPLATE_DECL)
1702 /* It was a specialization of an ordinary member function in a
1704 *targs_out = copy_node (DECL_TI_ARGS (fn));
1705 return DECL_TI_TEMPLATE (fn);
1708 /* It was a specialization of a template. */
1709 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1710 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1712 *targs_out = copy_node (targs);
1713 SET_TMPL_ARGS_LEVEL (*targs_out,
1714 TMPL_ARGS_DEPTH (*targs_out),
1715 TREE_PURPOSE (templates));
1718 *targs_out = TREE_PURPOSE (templates);
1719 return TREE_VALUE (templates);
1722 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1723 but with the default argument values filled in from those in the
1727 copy_default_args_to_explicit_spec_1 (tree spec_types,
1730 tree new_spec_types;
1735 if (spec_types == void_list_node)
1736 return void_list_node;
1738 /* Substitute into the rest of the list. */
1740 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1741 TREE_CHAIN (tmpl_types));
1743 /* Add the default argument for this parameter. */
1744 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1745 TREE_VALUE (spec_types),
1749 /* DECL is an explicit specialization. Replicate default arguments
1750 from the template it specializes. (That way, code like:
1752 template <class T> void f(T = 3);
1753 template <> void f(double);
1756 works, as required.) An alternative approach would be to look up
1757 the correct default arguments at the call-site, but this approach
1758 is consistent with how implicit instantiations are handled. */
1761 copy_default_args_to_explicit_spec (tree decl)
1766 tree new_spec_types;
1770 tree object_type = NULL_TREE;
1771 tree in_charge = NULL_TREE;
1772 tree vtt = NULL_TREE;
1774 /* See if there's anything we need to do. */
1775 tmpl = DECL_TI_TEMPLATE (decl);
1776 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1777 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1778 if (TREE_PURPOSE (t))
1783 old_type = TREE_TYPE (decl);
1784 spec_types = TYPE_ARG_TYPES (old_type);
1786 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1788 /* Remove the this pointer, but remember the object's type for
1790 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1791 spec_types = TREE_CHAIN (spec_types);
1792 tmpl_types = TREE_CHAIN (tmpl_types);
1794 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1796 /* DECL may contain more parameters than TMPL due to the extra
1797 in-charge parameter in constructors and destructors. */
1798 in_charge = spec_types;
1799 spec_types = TREE_CHAIN (spec_types);
1801 if (DECL_HAS_VTT_PARM_P (decl))
1804 spec_types = TREE_CHAIN (spec_types);
1808 /* Compute the merged default arguments. */
1810 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1812 /* Compute the new FUNCTION_TYPE. */
1816 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1821 /* Put the in-charge parameter back. */
1822 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1823 TREE_VALUE (in_charge),
1826 new_type = build_method_type_directly (object_type,
1827 TREE_TYPE (old_type),
1831 new_type = build_function_type (TREE_TYPE (old_type),
1833 new_type = cp_build_type_attribute_variant (new_type,
1834 TYPE_ATTRIBUTES (old_type));
1835 new_type = build_exception_variant (new_type,
1836 TYPE_RAISES_EXCEPTIONS (old_type));
1837 TREE_TYPE (decl) = new_type;
1840 /* Check to see if the function just declared, as indicated in
1841 DECLARATOR, and in DECL, is a specialization of a function
1842 template. We may also discover that the declaration is an explicit
1843 instantiation at this point.
1845 Returns DECL, or an equivalent declaration that should be used
1846 instead if all goes well. Issues an error message if something is
1847 amiss. Returns error_mark_node if the error is not easily
1850 FLAGS is a bitmask consisting of the following flags:
1852 2: The function has a definition.
1853 4: The function is a friend.
1855 The TEMPLATE_COUNT is the number of references to qualifying
1856 template classes that appeared in the name of the function. For
1859 template <class T> struct S { void f(); };
1862 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1863 classes are not counted in the TEMPLATE_COUNT, so that in
1865 template <class T> struct S {};
1866 template <> struct S<int> { void f(); }
1867 template <> void S<int>::f();
1869 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1870 invalid; there should be no template <>.)
1872 If the function is a specialization, it is marked as such via
1873 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1874 is set up correctly, and it is added to the list of specializations
1875 for that template. */
1878 check_explicit_specialization (tree declarator,
1883 int have_def = flags & 2;
1884 int is_friend = flags & 4;
1885 int specialization = 0;
1886 int explicit_instantiation = 0;
1887 int member_specialization = 0;
1888 tree ctype = DECL_CLASS_CONTEXT (decl);
1889 tree dname = DECL_NAME (decl);
1894 if (!processing_specialization)
1897 tsk = tsk_excessive_parms;
1900 tsk = current_tmpl_spec_kind (template_count);
1905 if (processing_specialization)
1908 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1910 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1913 /* This could be something like:
1915 template <class T> void f(T);
1916 class S { friend void f<>(int); } */
1920 /* This case handles bogus declarations like template <>
1921 template <class T> void f<int>(); */
1923 error ("template-id %qD in declaration of primary template",
1930 case tsk_invalid_member_spec:
1931 /* The error has already been reported in
1932 check_specialization_scope. */
1933 return error_mark_node;
1935 case tsk_invalid_expl_inst:
1936 error ("template parameter list used in explicit instantiation");
1942 error ("definition provided for explicit instantiation");
1944 explicit_instantiation = 1;
1947 case tsk_excessive_parms:
1948 case tsk_insufficient_parms:
1949 if (tsk == tsk_excessive_parms)
1950 error ("too many template parameter lists in declaration of %qD",
1952 else if (template_header_count)
1953 error("too few template parameter lists in declaration of %qD", decl);
1955 error("explicit specialization of %qD must be introduced by "
1956 "%<template <>%>", decl);
1960 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1962 member_specialization = 1;
1968 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1970 /* This case handles bogus declarations like template <>
1971 template <class T> void f<int>(); */
1973 if (uses_template_parms (declarator))
1974 error ("function template partial specialization %qD "
1975 "is not allowed", declarator);
1977 error ("template-id %qD in declaration of primary template",
1982 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1983 /* This is a specialization of a member template, without
1984 specialization the containing class. Something like:
1986 template <class T> struct S {
1987 template <class U> void f (U);
1989 template <> template <class U> void S<int>::f(U) {}
1991 That's a specialization -- but of the entire template. */
1999 if (specialization || member_specialization)
2001 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2002 for (; t; t = TREE_CHAIN (t))
2003 if (TREE_PURPOSE (t))
2006 ("default argument specified in explicit specialization");
2011 if (specialization || member_specialization || explicit_instantiation)
2013 tree tmpl = NULL_TREE;
2014 tree targs = NULL_TREE;
2016 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2017 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2021 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2026 /* If there is no class context, the explicit instantiation
2027 must be at namespace scope. */
2028 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2030 /* Find the namespace binding, using the declaration
2032 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2034 if (fns == error_mark_node || !is_overloaded_fn (fns))
2036 error ("%qD is not a template function", dname);
2037 fns = error_mark_node;
2041 tree fn = OVL_CURRENT (fns);
2042 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2043 CP_DECL_CONTEXT (fn)))
2044 error ("%qD is not declared in %qD",
2045 decl, current_namespace);
2049 declarator = lookup_template_function (fns, NULL_TREE);
2052 if (declarator == error_mark_node)
2053 return error_mark_node;
2055 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2057 if (!explicit_instantiation)
2058 /* A specialization in class scope. This is invalid,
2059 but the error will already have been flagged by
2060 check_specialization_scope. */
2061 return error_mark_node;
2064 /* It's not valid to write an explicit instantiation in
2067 class C { template void f(); }
2069 This case is caught by the parser. However, on
2072 template class C { void f(); };
2074 (which is invalid) we can get here. The error will be
2081 else if (ctype != NULL_TREE
2082 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2085 /* Find the list of functions in ctype that have the same
2086 name as the declared function. */
2087 tree name = TREE_OPERAND (declarator, 0);
2088 tree fns = NULL_TREE;
2091 if (constructor_name_p (name, ctype))
2093 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2095 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2096 : !CLASSTYPE_DESTRUCTORS (ctype))
2098 /* From [temp.expl.spec]:
2100 If such an explicit specialization for the member
2101 of a class template names an implicitly-declared
2102 special member function (clause _special_), the
2103 program is ill-formed.
2105 Similar language is found in [temp.explicit]. */
2106 error ("specialization of implicitly-declared special member function");
2107 return error_mark_node;
2110 name = is_constructor ? ctor_identifier : dtor_identifier;
2113 if (!DECL_CONV_FN_P (decl))
2115 idx = lookup_fnfields_1 (ctype, name);
2117 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2121 VEC(tree,gc) *methods;
2124 /* For a type-conversion operator, we cannot do a
2125 name-based lookup. We might be looking for `operator
2126 int' which will be a specialization of `operator T'.
2127 So, we find *all* the conversion operators, and then
2128 select from them. */
2131 methods = CLASSTYPE_METHOD_VEC (ctype);
2133 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2134 VEC_iterate (tree, methods, idx, ovl);
2137 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2138 /* There are no more conversion functions. */
2141 /* Glue all these conversion functions together
2142 with those we already have. */
2143 for (; ovl; ovl = OVL_NEXT (ovl))
2144 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2148 if (fns == NULL_TREE)
2150 error ("no member function %qD declared in %qT", name, ctype);
2151 return error_mark_node;
2154 TREE_OPERAND (declarator, 0) = fns;
2157 /* Figure out what exactly is being specialized at this point.
2158 Note that for an explicit instantiation, even one for a
2159 member function, we cannot tell apriori whether the
2160 instantiation is for a member template, or just a member
2161 function of a template class. Even if a member template is
2162 being instantiated, the member template arguments may be
2163 elided if they can be deduced from the rest of the
2165 tmpl = determine_specialization (declarator, decl,
2167 member_specialization,
2171 if (!tmpl || tmpl == error_mark_node)
2172 /* We couldn't figure out what this declaration was
2174 return error_mark_node;
2177 tree gen_tmpl = most_general_template (tmpl);
2179 if (explicit_instantiation)
2181 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2182 is done by do_decl_instantiation later. */
2184 int arg_depth = TMPL_ARGS_DEPTH (targs);
2185 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2187 if (arg_depth > parm_depth)
2189 /* If TMPL is not the most general template (for
2190 example, if TMPL is a friend template that is
2191 injected into namespace scope), then there will
2192 be too many levels of TARGS. Remove some of them
2197 new_targs = make_tree_vec (parm_depth);
2198 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2199 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2200 = TREE_VEC_ELT (targs, i);
2204 return instantiate_template (tmpl, targs, tf_error);
2207 /* If we thought that the DECL was a member function, but it
2208 turns out to be specializing a static member function,
2209 make DECL a static member function as well. */
2210 if (DECL_STATIC_FUNCTION_P (tmpl)
2211 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2212 revert_static_member_fn (decl);
2214 /* If this is a specialization of a member template of a
2215 template class, we want to return the TEMPLATE_DECL, not
2216 the specialization of it. */
2217 if (tsk == tsk_template)
2219 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2220 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2223 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2224 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2225 = DECL_SOURCE_LOCATION (decl);
2226 /* We want to use the argument list specified in the
2227 definition, not in the original declaration. */
2228 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2229 = DECL_ARGUMENTS (decl);
2234 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2235 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2237 /* Inherit default function arguments from the template
2238 DECL is specializing. */
2239 copy_default_args_to_explicit_spec (decl);
2241 /* This specialization has the same protection as the
2242 template it specializes. */
2243 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2244 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2246 /* 7.1.1-1 [dcl.stc]
2248 A storage-class-specifier shall not be specified in an
2249 explicit specialization...
2251 The parser rejects these, so unless action is taken here,
2252 explicit function specializations will always appear with
2255 The action recommended by the C++ CWG in response to C++
2256 defect report 605 is to make the storage class and linkage
2257 of the explicit specialization match the templated function:
2259 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2261 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2263 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2264 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2266 /* This specialization has the same linkage and visibility as
2267 the function template it specializes. */
2268 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2269 if (! TREE_PUBLIC (decl))
2271 DECL_INTERFACE_KNOWN (decl) = 1;
2272 DECL_NOT_REALLY_EXTERN (decl) = 1;
2274 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2275 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2277 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2278 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2282 /* If DECL is a friend declaration, declared using an
2283 unqualified name, the namespace associated with DECL may
2284 have been set incorrectly. For example, in:
2286 template <typename T> void f(T);
2288 struct S { friend void f<int>(int); }
2291 we will have set the DECL_CONTEXT for the friend
2292 declaration to N, rather than to the global namespace. */
2293 if (DECL_NAMESPACE_SCOPE_P (decl))
2294 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2296 if (is_friend && !have_def)
2297 /* This is not really a declaration of a specialization.
2298 It's just the name of an instantiation. But, it's not
2299 a request for an instantiation, either. */
2300 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2301 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2302 /* This is indeed a specialization. In case of constructors
2303 and destructors, we need in-charge and not-in-charge
2304 versions in V3 ABI. */
2305 clone_function_decl (decl, /*update_method_vec_p=*/0);
2307 /* Register this specialization so that we can find it
2309 decl = register_specialization (decl, gen_tmpl, targs, is_friend);
2316 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2317 parameters. These are represented in the same format used for
2318 DECL_TEMPLATE_PARMS. */
2321 comp_template_parms (const_tree parms1, const_tree parms2)
2326 if (parms1 == parms2)
2329 for (p1 = parms1, p2 = parms2;
2330 p1 != NULL_TREE && p2 != NULL_TREE;
2331 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2333 tree t1 = TREE_VALUE (p1);
2334 tree t2 = TREE_VALUE (p2);
2337 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2338 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2340 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2343 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2345 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2346 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2348 /* If either of the template parameters are invalid, assume
2349 they match for the sake of error recovery. */
2350 if (parm1 == error_mark_node || parm2 == error_mark_node)
2353 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2356 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2357 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2358 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2360 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2365 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2366 /* One set of parameters has more parameters lists than the
2373 /* Determine whether PARM is a parameter pack. */
2375 template_parameter_pack_p (const_tree parm)
2377 /* Determine if we have a non-type template parameter pack. */
2378 if (TREE_CODE (parm) == PARM_DECL)
2379 return (DECL_TEMPLATE_PARM_P (parm)
2380 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2382 /* If this is a list of template parameters, we could get a
2383 TYPE_DECL or a TEMPLATE_DECL. */
2384 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2385 parm = TREE_TYPE (parm);
2387 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2388 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2389 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2392 /* Determine whether ARGS describes a variadic template args list,
2393 i.e., one that is terminated by a template argument pack. */
2395 template_args_variadic_p (tree args)
2400 if (args == NULL_TREE)
2403 args = INNERMOST_TEMPLATE_ARGS (args);
2404 nargs = TREE_VEC_LENGTH (args);
2409 last_parm = TREE_VEC_ELT (args, nargs - 1);
2411 return ARGUMENT_PACK_P (last_parm);
2414 /* Generate a new name for the parameter pack name NAME (an
2415 IDENTIFIER_NODE) that incorporates its */
2417 make_ith_pack_parameter_name (tree name, int i)
2419 /* Munge the name to include the parameter index. */
2423 sprintf(numbuf, "%i", i);
2424 newname = (char*)alloca (IDENTIFIER_LENGTH (name) + strlen(numbuf) + 2);
2425 sprintf(newname, "%s#%i", IDENTIFIER_POINTER (name), i);
2426 return get_identifier (newname);
2429 /* Structure used to track the progress of find_parameter_packs_r. */
2430 struct find_parameter_pack_data
2432 /* TREE_LIST that will contain all of the parameter packs found by
2434 tree* parameter_packs;
2436 /* Set of AST nodes that have been visited by the traversal. */
2437 struct pointer_set_t *visited;
2440 /* Identifies all of the argument packs that occur in a template
2441 argument and appends them to the TREE_LIST inside DATA, which is a
2442 find_parameter_pack_data structure. This is a subroutine of
2443 make_pack_expansion and uses_parameter_packs. */
2445 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2448 struct find_parameter_pack_data* ppd =
2449 (struct find_parameter_pack_data*)data;
2450 bool parameter_pack_p = false;
2452 /* Identify whether this is a parameter pack or not. */
2453 switch (TREE_CODE (t))
2455 case TEMPLATE_PARM_INDEX:
2456 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2457 parameter_pack_p = true;
2460 case TEMPLATE_TYPE_PARM:
2461 case TEMPLATE_TEMPLATE_PARM:
2462 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2463 parameter_pack_p = true;
2467 if (FUNCTION_PARAMETER_PACK_P (t))
2469 /* We don't want to walk into the type of a PARM_DECL,
2470 because we don't want to see the type parameter pack. */
2472 parameter_pack_p = true;
2477 /* Not a parameter pack. */
2481 if (parameter_pack_p)
2483 /* Add this parameter pack to the list. */
2484 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2488 cp_walk_tree (&TYPE_CONTEXT (t),
2489 &find_parameter_packs_r, ppd, ppd->visited);
2491 /* This switch statement will return immediately if we don't find a
2493 switch (TREE_CODE (t))
2495 case TEMPLATE_PARM_INDEX:
2498 case BOUND_TEMPLATE_TEMPLATE_PARM:
2499 /* Check the template itself. */
2500 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2501 &find_parameter_packs_r, ppd, ppd->visited);
2502 /* Check the template arguments. */
2503 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2508 case TEMPLATE_TYPE_PARM:
2509 case TEMPLATE_TEMPLATE_PARM:
2516 if (TYPE_PTRMEMFUNC_P (t))
2522 if (TYPE_TEMPLATE_INFO (t))
2523 cp_walk_tree (&TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
2524 &find_parameter_packs_r, ppd, ppd->visited);
2530 cp_walk_tree (&TREE_TYPE (t),
2531 &find_parameter_packs_r, ppd, ppd->visited);
2535 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
2540 case TYPE_PACK_EXPANSION:
2541 case EXPR_PACK_EXPANSION:
2546 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
2551 case IDENTIFIER_NODE:
2552 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
2564 /* Determines if the expression or type T uses any parameter packs. */
2566 uses_parameter_packs (tree t)
2568 tree parameter_packs = NULL_TREE;
2569 struct find_parameter_pack_data ppd;
2570 ppd.parameter_packs = ¶meter_packs;
2571 ppd.visited = pointer_set_create ();
2572 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2573 pointer_set_destroy (ppd.visited);
2574 return parameter_packs != NULL_TREE;
2577 /* Turn ARG, which may be an expression, type, or a TREE_LIST
2578 representation a base-class initializer into a parameter pack
2579 expansion. If all goes well, the resulting node will be an
2580 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
2583 make_pack_expansion (tree arg)
2586 tree parameter_packs = NULL_TREE;
2587 bool for_types = false;
2588 struct find_parameter_pack_data ppd;
2590 if (!arg || arg == error_mark_node)
2593 if (TREE_CODE (arg) == TREE_LIST)
2595 /* The only time we will see a TREE_LIST here is for a base
2596 class initializer. In this case, the TREE_PURPOSE will be a
2597 _TYPE node (representing the base class expansion we're
2598 initializing) and the TREE_VALUE will be a TREE_LIST
2599 containing the initialization arguments.
2601 The resulting expansion looks somewhat different from most
2602 expansions. Rather than returning just one _EXPANSION, we
2603 return a TREE_LIST whose TREE_PURPOSE is a
2604 TYPE_PACK_EXPANSION containing the bases that will be
2605 initialized. The TREE_VALUE will be identical to the
2606 original TREE_VALUE, which is a list of arguments that will
2607 be passed to each base. We do not introduce any new pack
2608 expansion nodes into the TREE_VALUE (although it is possible
2609 that some already exist), because the TREE_PURPOSE and
2610 TREE_VALUE all need to be expanded together with the same
2611 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
2612 resulting TREE_PURPOSE will mention the parameter packs in
2613 both the bases and the arguments to the bases. */
2616 tree parameter_packs = NULL_TREE;
2618 /* Determine which parameter packs will be used by the base
2620 ppd.visited = pointer_set_create ();
2621 ppd.parameter_packs = ¶meter_packs;
2622 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
2625 if (parameter_packs == NULL_TREE)
2627 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
2628 pointer_set_destroy (ppd.visited);
2629 return error_mark_node;
2632 if (TREE_VALUE (arg) != void_type_node)
2634 /* Collect the sets of parameter packs used in each of the
2635 initialization arguments. */
2636 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
2638 /* Determine which parameter packs will be expanded in this
2640 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
2645 pointer_set_destroy (ppd.visited);
2647 /* Create the pack expansion type for the base type. */
2648 purpose = make_node (TYPE_PACK_EXPANSION);
2649 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
2650 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
2652 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2653 they will rarely be compared to anything. */
2654 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
2656 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
2659 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
2662 /* Build the PACK_EXPANSION_* node. */
2663 result = make_node (for_types ? TYPE_PACK_EXPANSION : EXPR_PACK_EXPANSION);
2664 SET_PACK_EXPANSION_PATTERN (result, arg);
2665 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
2667 /* Propagate type and const-expression information. */
2668 TREE_TYPE (result) = TREE_TYPE (arg);
2669 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
2672 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2673 they will rarely be compared to anything. */
2674 SET_TYPE_STRUCTURAL_EQUALITY (result);
2676 /* Determine which parameter packs will be expanded. */
2677 ppd.parameter_packs = ¶meter_packs;
2678 ppd.visited = pointer_set_create ();
2679 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
2680 pointer_set_destroy (ppd.visited);
2682 /* Make sure we found some parameter packs. */
2683 if (parameter_packs == NULL_TREE)
2686 error ("expansion pattern %<%T%> contains no argument packs", arg);
2688 error ("expansion pattern %<%E%> contains no argument packs", arg);
2689 return error_mark_node;
2691 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
2696 /* Checks T for any "bare" parameter packs, which have not yet been
2697 expanded, and issues an error if any are found. This operation can
2698 only be done on full expressions or types (e.g., an expression
2699 statement, "if" condition, etc.), because we could have expressions like:
2701 foo(f(g(h(args)))...)
2703 where "args" is a parameter pack. check_for_bare_parameter_packs
2704 should not be called for the subexpressions args, h(args),
2705 g(h(args)), or f(g(h(args))), because we would produce erroneous
2708 Returns TRUE and emits an error if there were bare parameter packs,
2709 returns FALSE otherwise. */
2711 check_for_bare_parameter_packs (tree t)
2713 tree parameter_packs = NULL_TREE;
2714 struct find_parameter_pack_data ppd;
2716 if (!processing_template_decl || !t || t == error_mark_node)
2719 if (TREE_CODE (t) == TYPE_DECL)
2722 ppd.parameter_packs = ¶meter_packs;
2723 ppd.visited = pointer_set_create ();
2724 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2725 pointer_set_destroy (ppd.visited);
2727 if (parameter_packs)
2729 error ("parameter packs not expanded with %<...%>:");
2730 while (parameter_packs)
2732 tree pack = TREE_VALUE (parameter_packs);
2733 tree name = NULL_TREE;
2735 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
2736 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
2737 name = TYPE_NAME (pack);
2738 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
2739 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
2741 name = DECL_NAME (pack);
2744 inform (" %qD", name);
2746 inform (" <anonymous>");
2748 parameter_packs = TREE_CHAIN (parameter_packs);
2757 /* Expand any parameter packs that occur in the template arguments in
2760 expand_template_argument_pack (tree args)
2762 tree result_args = NULL_TREE;
2763 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
2764 int num_result_args = -1;
2766 /* First, determine if we need to expand anything, and the number of
2767 slots we'll need. */
2768 for (in_arg = 0; in_arg < nargs; ++in_arg)
2770 tree arg = TREE_VEC_ELT (args, in_arg);
2771 if (ARGUMENT_PACK_P (arg))
2773 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
2774 if (num_result_args < 0)
2775 num_result_args = in_arg + num_packed;
2777 num_result_args += num_packed;
2781 if (num_result_args >= 0)
2786 /* If no expansion is necessary, we're done. */
2787 if (num_result_args < 0)
2790 /* Expand arguments. */
2791 result_args = make_tree_vec (num_result_args);
2792 for (in_arg = 0; in_arg < nargs; ++in_arg)
2794 tree arg = TREE_VEC_ELT (args, in_arg);
2795 if (ARGUMENT_PACK_P (arg))
2797 tree packed = ARGUMENT_PACK_ARGS (arg);
2798 int i, num_packed = TREE_VEC_LENGTH (packed);
2799 for (i = 0; i < num_packed; ++i, ++out_arg)
2800 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
2804 TREE_VEC_ELT (result_args, out_arg) = arg;
2812 /* Complain if DECL shadows a template parameter.
2814 [temp.local]: A template-parameter shall not be redeclared within its
2815 scope (including nested scopes). */
2818 check_template_shadow (tree decl)
2822 /* If we're not in a template, we can't possibly shadow a template
2824 if (!current_template_parms)
2827 /* Figure out what we're shadowing. */
2828 if (TREE_CODE (decl) == OVERLOAD)
2829 decl = OVL_CURRENT (decl);
2830 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2832 /* If there's no previous binding for this name, we're not shadowing
2833 anything, let alone a template parameter. */
2837 /* If we're not shadowing a template parameter, we're done. Note
2838 that OLDDECL might be an OVERLOAD (or perhaps even an
2839 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2841 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2844 /* We check for decl != olddecl to avoid bogus errors for using a
2845 name inside a class. We check TPFI to avoid duplicate errors for
2846 inline member templates. */
2848 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2851 error ("declaration of %q+#D", decl);
2852 error (" shadows template parm %q+#D", olddecl);
2855 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2856 ORIG_LEVEL, DECL, and TYPE. */
2859 build_template_parm_index (int index,
2865 tree t = make_node (TEMPLATE_PARM_INDEX);
2866 TEMPLATE_PARM_IDX (t) = index;
2867 TEMPLATE_PARM_LEVEL (t) = level;
2868 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2869 TEMPLATE_PARM_DECL (t) = decl;
2870 TREE_TYPE (t) = type;
2871 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2872 TREE_READONLY (t) = TREE_READONLY (decl);
2877 /* Find the canonical type parameter for the given template type
2878 parameter. Returns the canonical type parameter, which may be TYPE
2879 if no such parameter existed. */
2881 canonical_type_parameter (tree type)
2884 int idx = TEMPLATE_TYPE_IDX (type);
2885 if (!canonical_template_parms)
2886 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
2888 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
2889 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
2891 list = VEC_index (tree, canonical_template_parms, idx);
2892 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
2893 list = TREE_CHAIN (list);
2896 return TREE_VALUE (list);
2899 VEC_replace(tree, canonical_template_parms, idx,
2900 tree_cons (NULL_TREE, type,
2901 VEC_index (tree, canonical_template_parms, idx)));
2906 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2907 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2908 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2909 new one is created. */
2912 reduce_template_parm_level (tree index, tree type, int levels, tree args,
2913 tsubst_flags_t complain)
2915 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2916 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2917 != TEMPLATE_PARM_LEVEL (index) - levels))
2919 tree orig_decl = TEMPLATE_PARM_DECL (index);
2922 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2923 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2924 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2925 DECL_ARTIFICIAL (decl) = 1;
2926 SET_DECL_TEMPLATE_PARM_P (decl);
2928 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2929 TEMPLATE_PARM_LEVEL (index) - levels,
2930 TEMPLATE_PARM_ORIG_LEVEL (index),
2932 TEMPLATE_PARM_DESCENDANTS (index) = t;
2933 TEMPLATE_PARM_PARAMETER_PACK (t)
2934 = TEMPLATE_PARM_PARAMETER_PACK (index);
2936 /* Template template parameters need this. */
2937 if (TREE_CODE (decl) == TEMPLATE_DECL)
2938 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
2939 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
2943 return TEMPLATE_PARM_DESCENDANTS (index);
2946 /* Process information from new template parameter PARM and append it to the
2947 LIST being built. This new parameter is a non-type parameter iff
2948 IS_NON_TYPE is true. This new parameter is a parameter
2949 pack iff IS_PARAMETER_PACK is true. */
2952 process_template_parm (tree list, tree parm, bool is_non_type,
2953 bool is_parameter_pack)
2960 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2961 defval = TREE_PURPOSE (parm);
2965 tree p = tree_last (list);
2967 if (p && TREE_VALUE (p) != error_mark_node)
2970 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2971 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2973 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2983 parm = TREE_VALUE (parm);
2985 SET_DECL_TEMPLATE_PARM_P (parm);
2987 if (TREE_TYPE (parm) == error_mark_node)
2989 err_parm_list = build_tree_list (defval, parm);
2990 TREE_VALUE (err_parm_list) = error_mark_node;
2991 return chainon (list, err_parm_list);
2997 The top-level cv-qualifiers on the template-parameter are
2998 ignored when determining its type. */
2999 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3000 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3002 err_parm_list = build_tree_list (defval, parm);
3003 TREE_VALUE (err_parm_list) = error_mark_node;
3004 return chainon (list, err_parm_list);
3007 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3009 /* This template parameter is not a parameter pack, but it
3010 should be. Complain about "bare" parameter packs. */
3011 check_for_bare_parameter_packs (TREE_TYPE (parm));
3013 /* Recover by calling this a parameter pack. */
3014 is_parameter_pack = true;
3018 /* A template parameter is not modifiable. */
3019 TREE_CONSTANT (parm) = 1;
3020 TREE_READONLY (parm) = 1;
3021 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3022 TREE_CONSTANT (decl) = 1;
3023 TREE_READONLY (decl) = 1;
3024 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3025 = build_template_parm_index (idx, processing_template_decl,
3026 processing_template_decl,
3027 decl, TREE_TYPE (parm));
3029 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3030 = is_parameter_pack;
3035 parm = TREE_VALUE (TREE_VALUE (parm));
3037 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3039 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3040 /* This is for distinguishing between real templates and template
3041 template parameters */
3042 TREE_TYPE (parm) = t;
3043 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3048 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3049 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3050 decl = build_decl (TYPE_DECL, parm, t);
3053 TYPE_NAME (t) = decl;
3054 TYPE_STUB_DECL (t) = decl;
3056 TEMPLATE_TYPE_PARM_INDEX (t)
3057 = build_template_parm_index (idx, processing_template_decl,
3058 processing_template_decl,
3059 decl, TREE_TYPE (parm));
3060 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3061 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3063 DECL_ARTIFICIAL (decl) = 1;
3064 SET_DECL_TEMPLATE_PARM_P (decl);
3066 parm = build_tree_list (defval, parm);
3067 return chainon (list, parm);
3070 /* The end of a template parameter list has been reached. Process the
3071 tree list into a parameter vector, converting each parameter into a more
3072 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3076 end_template_parm_list (tree parms)
3080 tree saved_parmlist = make_tree_vec (list_length (parms));
3082 current_template_parms
3083 = tree_cons (size_int (processing_template_decl),
3084 saved_parmlist, current_template_parms);
3086 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3088 next = TREE_CHAIN (parm);
3089 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3090 TREE_CHAIN (parm) = NULL_TREE;
3093 --processing_template_parmlist;
3095 return saved_parmlist;
3098 /* end_template_decl is called after a template declaration is seen. */
3101 end_template_decl (void)
3103 reset_specialization ();
3105 if (! processing_template_decl)
3108 /* This matches the pushlevel in begin_template_parm_list. */
3111 --processing_template_decl;
3112 current_template_parms = TREE_CHAIN (current_template_parms);
3115 /* Within the declaration of a template, return all levels of template
3116 parameters that apply. The template parameters are represented as
3117 a TREE_VEC, in the form documented in cp-tree.h for template
3121 current_template_args (void)
3124 tree args = NULL_TREE;
3125 int length = TMPL_PARMS_DEPTH (current_template_parms);
3128 /* If there is only one level of template parameters, we do not
3129 create a TREE_VEC of TREE_VECs. Instead, we return a single
3130 TREE_VEC containing the arguments. */
3132 args = make_tree_vec (length);
3134 for (header = current_template_parms; header; header = TREE_CHAIN (header))
3136 tree a = copy_node (TREE_VALUE (header));
3139 TREE_TYPE (a) = NULL_TREE;
3140 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3142 tree t = TREE_VEC_ELT (a, i);
3144 /* T will be a list if we are called from within a
3145 begin/end_template_parm_list pair, but a vector directly
3146 if within a begin/end_member_template_processing pair. */
3147 if (TREE_CODE (t) == TREE_LIST)
3151 if (!error_operand_p (t))
3153 if (TREE_CODE (t) == TYPE_DECL
3154 || TREE_CODE (t) == TEMPLATE_DECL)
3158 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3160 /* Turn this argument into a TYPE_ARGUMENT_PACK
3161 with a single element, which expands T. */
3162 tree vec = make_tree_vec (1);
3163 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3165 t = make_node (TYPE_ARGUMENT_PACK);
3166 SET_ARGUMENT_PACK_ARGS (t, vec);
3171 t = DECL_INITIAL (t);
3173 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3175 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3176 with a single element, which expands T. */
3177 tree vec = make_tree_vec (1);
3178 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3179 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3181 t = make_node (NONTYPE_ARGUMENT_PACK);
3182 SET_ARGUMENT_PACK_ARGS (t, vec);
3183 TREE_TYPE (t) = type;
3186 TREE_VEC_ELT (a, i) = t;
3192 TREE_VEC_ELT (args, --l) = a;
3200 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3201 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3202 a member template. Used by push_template_decl below. */
3205 build_template_decl (tree decl, tree parms, bool member_template_p)
3207 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3208 DECL_TEMPLATE_PARMS (tmpl) = parms;
3209 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3210 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3211 if (DECL_LANG_SPECIFIC (decl))
3213 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
3214 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
3215 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
3216 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
3217 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
3218 if (DECL_OVERLOADED_OPERATOR_P (decl))
3219 SET_OVERLOADED_OPERATOR_CODE (tmpl,
3220 DECL_OVERLOADED_OPERATOR_P (decl));
3226 struct template_parm_data
3228 /* The level of the template parameters we are currently
3232 /* The index of the specialization argument we are currently
3236 /* An array whose size is the number of template parameters. The
3237 elements are nonzero if the parameter has been used in any one
3238 of the arguments processed so far. */
3241 /* An array whose size is the number of template arguments. The
3242 elements are nonzero if the argument makes use of template
3243 parameters of this level. */
3244 int* arg_uses_template_parms;
3247 /* Subroutine of push_template_decl used to see if each template
3248 parameter in a partial specialization is used in the explicit
3249 argument list. If T is of the LEVEL given in DATA (which is
3250 treated as a template_parm_data*), then DATA->PARMS is marked
3254 mark_template_parm (tree t, void* data)
3258 struct template_parm_data* tpd = (struct template_parm_data*) data;
3260 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3262 level = TEMPLATE_PARM_LEVEL (t);
3263 idx = TEMPLATE_PARM_IDX (t);
3267 level = TEMPLATE_TYPE_LEVEL (t);
3268 idx = TEMPLATE_TYPE_IDX (t);
3271 if (level == tpd->level)
3273 tpd->parms[idx] = 1;
3274 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
3277 /* Return zero so that for_each_template_parm will continue the
3278 traversal of the tree; we want to mark *every* template parm. */
3282 /* Process the partial specialization DECL. */
3285 process_partial_specialization (tree decl)
3287 tree type = TREE_TYPE (decl);
3288 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
3289 tree specargs = CLASSTYPE_TI_ARGS (type);
3290 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
3291 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3292 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
3293 int nargs = TREE_VEC_LENGTH (inner_args);
3294 int ntparms = TREE_VEC_LENGTH (inner_parms);
3296 int did_error_intro = 0;
3297 struct template_parm_data tpd;
3298 struct template_parm_data tpd2;
3300 /* We check that each of the template parameters given in the
3301 partial specialization is used in the argument list to the
3302 specialization. For example:
3304 template <class T> struct S;
3305 template <class T> struct S<T*>;
3307 The second declaration is OK because `T*' uses the template
3308 parameter T, whereas
3310 template <class T> struct S<int>;
3312 is no good. Even trickier is:
3323 The S2<T> declaration is actually invalid; it is a
3324 full-specialization. Of course,
3327 struct S2<T (*)(U)>;
3329 or some such would have been OK. */
3330 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
3331 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
3332 memset (tpd.parms, 0, sizeof (int) * ntparms);
3334 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
3335 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
3336 for (i = 0; i < nargs; ++i)
3338 tpd.current_arg = i;
3339 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
3340 &mark_template_parm,
3343 /*include_nondeduced_p=*/false);
3345 for (i = 0; i < ntparms; ++i)
3346 if (tpd.parms[i] == 0)
3348 /* One of the template parms was not used in the
3350 if (!did_error_intro)
3352 error ("template parameters not used in partial specialization:");
3353 did_error_intro = 1;
3356 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
3359 /* [temp.class.spec]
3361 The argument list of the specialization shall not be identical to
3362 the implicit argument list of the primary template. */
3363 if (comp_template_args
3365 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
3367 error ("partial specialization %qT does not specialize any template arguments", type);
3369 /* [temp.class.spec]
3371 A partially specialized non-type argument expression shall not
3372 involve template parameters of the partial specialization except
3373 when the argument expression is a simple identifier.
3375 The type of a template parameter corresponding to a specialized
3376 non-type argument shall not be dependent on a parameter of the
3379 Also, we verify that pack expansions only occur at the
3380 end of the argument list. */
3381 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
3383 for (i = 0; i < nargs; ++i)
3385 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
3386 tree arg = TREE_VEC_ELT (inner_args, i);
3387 tree packed_args = NULL_TREE;
3390 if (ARGUMENT_PACK_P (arg))
3392 /* Extract the arguments from the argument pack. We'll be
3393 iterating over these in the following loop. */
3394 packed_args = ARGUMENT_PACK_ARGS (arg);
3395 len = TREE_VEC_LENGTH (packed_args);
3398 for (j = 0; j < len; j++)
3401 /* Get the Jth argument in the parameter pack. */
3402 arg = TREE_VEC_ELT (packed_args, j);
3404 if (PACK_EXPANSION_P (arg))
3406 /* Pack expansions must come at the end of the
3408 if ((packed_args && j < len - 1)
3409 || (!packed_args && i < nargs - 1))
3411 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3412 error ("parameter pack argument %qE must be at the end of the template argument list", arg);
3414 error ("parameter pack argument %qT must be at the end of the template argument list", arg);
3417 TREE_VEC_ELT (packed_args, j) = error_mark_node;
3421 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3422 /* We only care about the pattern. */
3423 arg = PACK_EXPANSION_PATTERN (arg);
3425 if (/* These first two lines are the `non-type' bit. */
3427 && TREE_CODE (arg) != TEMPLATE_DECL
3428 /* This next line is the `argument expression is not just a
3429 simple identifier' condition and also the `specialized
3430 non-type argument' bit. */
3431 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
3433 if ((!packed_args && tpd.arg_uses_template_parms[i])
3434 || (packed_args && uses_template_parms (arg)))
3435 error ("template argument %qE involves template parameter(s)",
3439 /* Look at the corresponding template parameter,
3440 marking which template parameters its type depends
3442 tree type = TREE_TYPE (parm);
3446 /* We haven't yet initialized TPD2. Do so now. */
3447 tpd2.arg_uses_template_parms
3448 = (int *) alloca (sizeof (int) * nargs);
3449 /* The number of parameters here is the number in the
3450 main template, which, as checked in the assertion
3452 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
3454 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
3457 /* Mark the template parameters. But this time, we're
3458 looking for the template parameters of the main
3459 template, not in the specialization. */
3460 tpd2.current_arg = i;
3461 tpd2.arg_uses_template_parms[i] = 0;
3462 memset (tpd2.parms, 0, sizeof (int) * nargs);
3463 for_each_template_parm (type,
3464 &mark_template_parm,
3467 /*include_nondeduced_p=*/false);
3469 if (tpd2.arg_uses_template_parms [i])
3471 /* The type depended on some template parameters.
3472 If they are fully specialized in the
3473 specialization, that's OK. */
3475 for (j = 0; j < nargs; ++j)
3476 if (tpd2.parms[j] != 0
3477 && tpd.arg_uses_template_parms [j])
3479 error ("type %qT of template argument %qE depends "
3480 "on template parameter(s)",
3491 if (retrieve_specialization (maintmpl, specargs,
3492 /*class_specializations_p=*/true))
3493 /* We've already got this specialization. */
3496 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
3497 = tree_cons (specargs, inner_parms,
3498 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
3499 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
3503 /* Check that a template declaration's use of default arguments and
3504 parameter packs is not invalid. Here, PARMS are the template
3505 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
3506 a primary template. IS_PARTIAL is nonzero if DECL is a partial
3510 IS_FRIEND_DECL is nonzero if DECL is a friend function template
3511 declaration (but not a definition); 1 indicates a declaration, 2
3512 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
3513 emitted for extraneous default arguments.
3515 Returns TRUE if there were no errors found, FALSE otherwise. */
3518 check_default_tmpl_args (tree decl, tree parms, int is_primary,
3519 int is_partial, int is_friend_decl)
3522 int last_level_to_check;
3524 bool no_errors = true;
3528 A default template-argument shall not be specified in a
3529 function template declaration or a function template definition, nor
3530 in the template-parameter-list of the definition of a member of a
3533 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
3534 /* You can't have a function template declaration in a local
3535 scope, nor you can you define a member of a class template in a
3539 if (current_class_type
3540 && !TYPE_BEING_DEFINED (current_class_type)
3541 && DECL_LANG_SPECIFIC (decl)
3542 /* If this is either a friend defined in the scope of the class
3543 or a member function. */
3544 && (DECL_FUNCTION_MEMBER_P (decl)
3545 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
3546 : DECL_FRIEND_CONTEXT (decl)
3547 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
3549 /* And, if it was a member function, it really was defined in
3550 the scope of the class. */
3551 && (!DECL_FUNCTION_MEMBER_P (decl)
3552 || DECL_INITIALIZED_IN_CLASS_P (decl)))
3553 /* We already checked these parameters when the template was
3554 declared, so there's no need to do it again now. This function
3555 was defined in class scope, but we're processing it's body now
3556 that the class is complete. */
3559 /* Core issue 226 (C++0x only): the following only applies to class
3561 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
3565 If a template-parameter has a default template-argument, all
3566 subsequent template-parameters shall have a default
3567 template-argument supplied. */
3568 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
3570 tree inner_parms = TREE_VALUE (parm_level);
3571 int ntparms = TREE_VEC_LENGTH (inner_parms);
3572 int seen_def_arg_p = 0;
3575 for (i = 0; i < ntparms; ++i)
3577 tree parm = TREE_VEC_ELT (inner_parms, i);
3579 if (parm == error_mark_node)
3582 if (TREE_PURPOSE (parm))
3584 else if (seen_def_arg_p)
3586 error ("no default argument for %qD", TREE_VALUE (parm));
3587 /* For better subsequent error-recovery, we indicate that
3588 there should have been a default argument. */
3589 TREE_PURPOSE (parm) = error_mark_node;
3595 && TREE_CODE (decl) == TYPE_DECL
3597 && template_parameter_pack_p (TREE_VALUE (parm)))
3599 /* A primary class template can only have one
3600 parameter pack, at the end of the template
3603 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
3604 error ("parameter pack %qE must be at the end of the"
3605 " template parameter list", TREE_VALUE (parm));
3607 error ("parameter pack %qT must be at the end of the"
3608 " template parameter list",
3609 TREE_TYPE (TREE_VALUE (parm)));
3611 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
3619 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
3623 /* For an ordinary class template, default template arguments are
3624 allowed at the innermost level, e.g.:
3625 template <class T = int>
3627 but, in a partial specialization, they're not allowed even
3628 there, as we have in [temp.class.spec]:
3630 The template parameter list of a specialization shall not
3631 contain default template argument values.
3633 So, for a partial specialization, or for a function template
3634 (in C++98/C++03), we look at all of them. */
3637 /* But, for a primary class template that is not a partial
3638 specialization we look at all template parameters except the
3640 parms = TREE_CHAIN (parms);
3642 /* Figure out what error message to issue. */
3643 if (is_friend_decl == 2)
3644 msg = "default template arguments may not be used in function template friend re-declaration";
3645 else if (is_friend_decl)
3646 msg = "default template arguments may not be used in function template friend declarations";
3647 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
3648 msg = "default template arguments may not be used in function templates";
3649 else if (is_partial)
3650 msg = "default template arguments may not be used in partial specializations";
3652 msg = "default argument for template parameter for class enclosing %qD";
3654 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
3655 /* If we're inside a class definition, there's no need to
3656 examine the parameters to the class itself. On the one
3657 hand, they will be checked when the class is defined, and,
3658 on the other, default arguments are valid in things like:
3659 template <class T = double>
3660 struct S { template <class U> void f(U); };
3661 Here the default argument for `S' has no bearing on the
3662 declaration of `f'. */
3663 last_level_to_check = template_class_depth (current_class_type) + 1;
3665 /* Check everything. */
3666 last_level_to_check = 0;
3668 for (parm_level = parms;
3669 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
3670 parm_level = TREE_CHAIN (parm_level))
3672 tree inner_parms = TREE_VALUE (parm_level);
3676 ntparms = TREE_VEC_LENGTH (inner_parms);
3677 for (i = 0; i < ntparms; ++i)
3679 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
3682 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
3687 if (is_friend_decl == 2)
3694 /* Clear out the default argument so that we are not
3696 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
3700 /* At this point, if we're still interested in issuing messages,
3701 they must apply to classes surrounding the object declared. */
3703 msg = "default argument for template parameter for class enclosing %qD";
3709 /* Worker for push_template_decl_real, called via
3710 for_each_template_parm. DATA is really an int, indicating the
3711 level of the parameters we are interested in. If T is a template
3712 parameter of that level, return nonzero. */
3715 template_parm_this_level_p (tree t, void* data)
3717 int this_level = *(int *)data;
3720 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3721 level = TEMPLATE_PARM_LEVEL (t);
3723 level = TEMPLATE_TYPE_LEVEL (t);
3724 return level == this_level;
3727 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
3728 parameters given by current_template_args, or reuses a
3729 previously existing one, if appropriate. Returns the DECL, or an
3730 equivalent one, if it is replaced via a call to duplicate_decls.
3732 If IS_FRIEND is true, DECL is a friend declaration. */
3735 push_template_decl_real (tree decl, bool is_friend)
3743 int new_template_p = 0;
3744 /* True if the template is a member template, in the sense of
3746 bool member_template_p = false;
3748 if (decl == error_mark_node)
3751 /* See if this is a partial specialization. */
3752 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
3753 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3754 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
3756 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
3760 /* For a friend, we want the context of the friend function, not
3761 the type of which it is a friend. */
3762 ctx = DECL_CONTEXT (decl);
3763 else if (CP_DECL_CONTEXT (decl)
3764 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
3765 /* In the case of a virtual function, we want the class in which
3767 ctx = CP_DECL_CONTEXT (decl);
3769 /* Otherwise, if we're currently defining some class, the DECL
3770 is assumed to be a member of the class. */
3771 ctx = current_scope ();
3773 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
3776 if (!DECL_CONTEXT (decl))
3777 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
3779 /* See if this is a primary template. */
3780 if (is_friend && ctx)
3781 /* A friend template that specifies a class context, i.e.
3782 template <typename T> friend void A<T>::f();
3786 primary = template_parm_scope_p ();
3790 if (DECL_CLASS_SCOPE_P (decl))
3791 member_template_p = true;
3792 if (TREE_CODE (decl) == TYPE_DECL
3793 && ANON_AGGRNAME_P (DECL_NAME (decl)))
3795 error ("template class without a name");
3796 return error_mark_node;
3798 else if (TREE_CODE (decl) == FUNCTION_DECL)
3800 if (DECL_DESTRUCTOR_P (decl))
3804 A destructor shall not be a member template. */
3805 error ("destructor %qD declared as member template", decl);
3806 return error_mark_node;
3808 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
3809 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
3810 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
3811 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
3812 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
3813 == void_list_node)))
3815 /* [basic.stc.dynamic.allocation]
3817 An allocation function can be a function
3818 template. ... Template allocation functions shall
3819 have two or more parameters. */
3820 error ("invalid template declaration of %qD", decl);
3821 return error_mark_node;
3824 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3825 && CLASS_TYPE_P (TREE_TYPE (decl)))
3829 error ("template declaration of %q#D", decl);
3830 return error_mark_node;
3834 /* Check to see that the rules regarding the use of default
3835 arguments are not being violated. */
3836 check_default_tmpl_args (decl, current_template_parms,
3837 primary, is_partial, /*is_friend_decl=*/0);
3839 /* Ensure that there are no parameter packs in the type of this
3840 declaration that have not been expanded. */
3841 if (TREE_CODE (decl) == FUNCTION_DECL)
3843 /* Check each of the arguments individually to see if there are
3844 any bare parameter packs. */
3845 tree type = TREE_TYPE (decl);
3846 tree arg = DECL_ARGUMENTS (decl);
3847 tree argtype = TYPE_ARG_TYPES (type);
3849 while (arg && argtype)
3851 if (!FUNCTION_PARAMETER_PACK_P (arg)
3852 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
3854 /* This is a PARM_DECL that contains unexpanded parameter
3855 packs. We have already complained about this in the
3856 check_for_bare_parameter_packs call, so just replace
3857 these types with ERROR_MARK_NODE. */
3858 TREE_TYPE (arg) = error_mark_node;
3859 TREE_VALUE (argtype) = error_mark_node;
3862 arg = TREE_CHAIN (arg);
3863 argtype = TREE_CHAIN (argtype);
3866 /* Check for bare parameter packs in the return type and the
3867 exception specifiers. */
3868 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
3869 /* Errors were already issued, set return type to int
3870 as the frontend doesn't expect error_mark_node as
3872 TREE_TYPE (type) = integer_type_node;
3873 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
3874 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
3876 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
3878 TREE_TYPE (decl) = error_mark_node;
3879 return error_mark_node;
3883 return process_partial_specialization (decl);
3885 args = current_template_args ();
3888 || TREE_CODE (ctx) == FUNCTION_DECL
3889 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3890 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3892 if (DECL_LANG_SPECIFIC (decl)
3893 && DECL_TEMPLATE_INFO (decl)
3894 && DECL_TI_TEMPLATE (decl))
3895 tmpl = DECL_TI_TEMPLATE (decl);
3896 /* If DECL is a TYPE_DECL for a class-template, then there won't
3897 be DECL_LANG_SPECIFIC. The information equivalent to
3898 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3899 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3900 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3901 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3903 /* Since a template declaration already existed for this
3904 class-type, we must be redeclaring it here. Make sure
3905 that the redeclaration is valid. */
3906 redeclare_class_template (TREE_TYPE (decl),
3907 current_template_parms);
3908 /* We don't need to create a new TEMPLATE_DECL; just use the
3909 one we already had. */
3910 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3914 tmpl = build_template_decl (decl, current_template_parms,
3918 if (DECL_LANG_SPECIFIC (decl)
3919 && DECL_TEMPLATE_SPECIALIZATION (decl))
3921 /* A specialization of a member template of a template
3923 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3924 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3925 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3931 tree a, t, current, parms;
3933 tree tinfo = get_template_info (decl);
3937 error ("template definition of non-template %q#D", decl);
3938 return error_mark_node;
3941 tmpl = TI_TEMPLATE (tinfo);
3943 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3944 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3945 && DECL_TEMPLATE_SPECIALIZATION (decl)
3946 && DECL_MEMBER_TEMPLATE_P (tmpl))
3950 /* The declaration is a specialization of a member
3951 template, declared outside the class. Therefore, the
3952 innermost template arguments will be NULL, so we
3953 replace them with the arguments determined by the
3954 earlier call to check_explicit_specialization. */
3955 args = DECL_TI_ARGS (decl);
3958 = build_template_decl (decl, current_template_parms,
3960 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3961 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3962 DECL_TI_TEMPLATE (decl) = new_tmpl;
3963 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3964 DECL_TEMPLATE_INFO (new_tmpl)
3965 = tree_cons (tmpl, args, NULL_TREE);
3967 register_specialization (new_tmpl,
3968 most_general_template (tmpl),
3974 /* Make sure the template headers we got make sense. */
3976 parms = DECL_TEMPLATE_PARMS (tmpl);
3977 i = TMPL_PARMS_DEPTH (parms);
3978 if (TMPL_ARGS_DEPTH (args) != i)
3980 error ("expected %d levels of template parms for %q#D, got %d",
3981 i, decl, TMPL_ARGS_DEPTH (args));
3984 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3986 a = TMPL_ARGS_LEVEL (args, i);
3987 t = INNERMOST_TEMPLATE_PARMS (parms);
3989 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3991 if (current == decl)
3992 error ("got %d template parameters for %q#D",
3993 TREE_VEC_LENGTH (a), decl);
3995 error ("got %d template parameters for %q#T",
3996 TREE_VEC_LENGTH (a), current);
3997 error (" but %d required", TREE_VEC_LENGTH (t));
3998 return error_mark_node;
4001 if (current == decl)
4004 current = (TYPE_P (current)
4005 ? TYPE_CONTEXT (current)
4006 : DECL_CONTEXT (current));
4009 /* Check that the parms are used in the appropriate qualifying scopes
4010 in the declarator. */
4011 if (!comp_template_args
4013 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4016 template arguments to %qD do not match original template %qD",
4017 decl, DECL_TEMPLATE_RESULT (tmpl));
4018 if (!uses_template_parms (TI_ARGS (tinfo)))
4019 inform ("use template<> for an explicit specialization");
4020 /* Avoid crash in import_export_decl. */
4021 DECL_INTERFACE_KNOWN (decl) = 1;
4022 return error_mark_node;
4026 DECL_TEMPLATE_RESULT (tmpl) = decl;
4027 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4029 /* Push template declarations for global functions and types. Note
4030 that we do not try to push a global template friend declared in a
4031 template class; such a thing may well depend on the template
4032 parameters of the class. */
4033 if (new_template_p && !ctx
4034 && !(is_friend && template_class_depth (current_class_type) > 0))
4036 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4037 if (tmpl == error_mark_node)
4038 return error_mark_node;
4040 /* Hide template friend classes that haven't been declared yet. */
4041 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4043 DECL_ANTICIPATED (tmpl) = 1;
4044 DECL_FRIEND_P (tmpl) = 1;
4050 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4053 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4054 if (DECL_CONV_FN_P (tmpl))
4056 int depth = TMPL_PARMS_DEPTH (parms);
4058 /* It is a conversion operator. See if the type converted to
4059 depends on innermost template operands. */
4061 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4063 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4066 /* Give template template parms a DECL_CONTEXT of the template
4067 for which they are a parameter. */
4068 parms = INNERMOST_TEMPLATE_PARMS (parms);
4069 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4071 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4072 if (TREE_CODE (parm) == TEMPLATE_DECL)
4073 DECL_CONTEXT (parm) = tmpl;
4077 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4078 back to its most general template. If TMPL is a specialization,
4079 ARGS may only have the innermost set of arguments. Add the missing
4080 argument levels if necessary. */
4081 if (DECL_TEMPLATE_INFO (tmpl))
4082 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4084 info = tree_cons (tmpl, args, NULL_TREE);
4086 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4087 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4088 else if (DECL_LANG_SPECIFIC (decl))
4089 DECL_TEMPLATE_INFO (decl) = info;
4091 return DECL_TEMPLATE_RESULT (tmpl);
4095 push_template_decl (tree decl)
4097 return push_template_decl_real (decl, false);
4100 /* Called when a class template TYPE is redeclared with the indicated
4101 template PARMS, e.g.:
4103 template <class T> struct S;
4104 template <class T> struct S {}; */
4107 redeclare_class_template (tree type, tree parms)
4113 if (!TYPE_TEMPLATE_INFO (type))
4115 error ("%qT is not a template type", type);
4119 tmpl = TYPE_TI_TEMPLATE (type);
4120 if (!PRIMARY_TEMPLATE_P (tmpl))
4121 /* The type is nested in some template class. Nothing to worry
4122 about here; there are no new template parameters for the nested
4128 error ("template specifiers not specified in declaration of %qD",
4133 parms = INNERMOST_TEMPLATE_PARMS (parms);
4134 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4136 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4138 error ("redeclared with %d template parameter(s)",
4139 TREE_VEC_LENGTH (parms));
4140 inform ("previous declaration %q+D used %d template parameter(s)",
4141 tmpl, TREE_VEC_LENGTH (tmpl_parms));
4145 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4152 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4153 || TREE_VEC_ELT (parms, i) == error_mark_node)
4156 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4157 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4158 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4159 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4161 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
4163 if (tmpl_parm != error_mark_node
4164 && (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
4165 || (TREE_CODE (tmpl_parm) != TYPE_DECL
4166 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
4167 || (TREE_CODE (tmpl_parm) != PARM_DECL
4168 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
4169 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
4170 || (TREE_CODE (tmpl_parm) == PARM_DECL
4171 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
4172 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))))))
4174 error ("template parameter %q+#D", tmpl_parm);
4175 error ("redeclared here as %q#D", parm);
4179 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
4181 /* We have in [temp.param]:
4183 A template-parameter may not be given default arguments
4184 by two different declarations in the same scope. */
4185 error ("redefinition of default argument for %q#D", parm);
4186 inform ("%Joriginal definition appeared here", tmpl_parm);
4190 if (parm_default != NULL_TREE)
4191 /* Update the previous template parameters (which are the ones
4192 that will really count) with the new default value. */
4193 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
4194 else if (tmpl_default != NULL_TREE)
4195 /* Update the new parameters, too; they'll be used as the
4196 parameters for any members. */
4197 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
4203 /* Simplify EXPR if it is a non-dependent expression. Returns the
4204 (possibly simplified) expression. */
4207 fold_non_dependent_expr (tree expr)
4209 if (expr == NULL_TREE)
4212 /* If we're in a template, but EXPR isn't value dependent, simplify
4213 it. We're supposed to treat:
4215 template <typename T> void f(T[1 + 1]);
4216 template <typename T> void f(T[2]);
4218 as two declarations of the same function, for example. */
4219 if (processing_template_decl
4220 && !type_dependent_expression_p (expr)
4221 && !value_dependent_expression_p (expr))
4223 HOST_WIDE_INT saved_processing_template_decl;
4225 saved_processing_template_decl = processing_template_decl;
4226 processing_template_decl = 0;
4227 expr = tsubst_copy_and_build (expr,
4230 /*in_decl=*/NULL_TREE,
4231 /*function_p=*/false,
4232 /*integral_constant_expression_p=*/true);
4233 processing_template_decl = saved_processing_template_decl;
4238 /* EXPR is an expression which is used in a constant-expression context.
4239 For instance, it could be a VAR_DECL with a constant initializer.
4240 Extract the innermost constant expression.
4242 This is basically a more powerful version of
4243 integral_constant_value, which can be used also in templates where
4244 initializers can maintain a syntactic rather than semantic form
4245 (even if they are non-dependent, for access-checking purposes). */
4248 fold_decl_constant_value (tree expr)
4250 tree const_expr = expr;
4253 expr = fold_non_dependent_expr (const_expr);
4254 const_expr = integral_constant_value (expr);
4256 while (expr != const_expr);
4261 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
4262 must be a function or a pointer-to-function type, as specified
4263 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
4264 and check that the resulting function has external linkage. */
4267 convert_nontype_argument_function (tree type, tree expr)
4272 fn = instantiate_type (type, fns, tf_none);
4273 if (fn == error_mark_node)
4274 return error_mark_node;
4277 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
4278 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
4279 if (TREE_CODE (fn_no_ptr) == BASELINK)
4280 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
4282 /* [temp.arg.nontype]/1
4284 A template-argument for a non-type, non-template template-parameter
4287 -- the address of an object or function with external linkage. */
4288 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
4290 error ("%qE is not a valid template argument for type %qT "
4291 "because function %qD has not external linkage",
4292 expr, type, fn_no_ptr);
4299 /* Attempt to convert the non-type template parameter EXPR to the
4300 indicated TYPE. If the conversion is successful, return the
4301 converted value. If the conversion is unsuccessful, return
4302 NULL_TREE if we issued an error message, or error_mark_node if we
4303 did not. We issue error messages for out-and-out bad template
4304 parameters, but not simply because the conversion failed, since we
4305 might be just trying to do argument deduction. Both TYPE and EXPR
4306 must be non-dependent.
4308 The conversion follows the special rules described in
4309 [temp.arg.nontype], and it is much more strict than an implicit
4312 This function is called twice for each template argument (see
4313 lookup_template_class for a more accurate description of this
4314 problem). This means that we need to handle expressions which
4315 are not valid in a C++ source, but can be created from the
4316 first call (for instance, casts to perform conversions). These
4317 hacks can go away after we fix the double coercion problem. */
4320 convert_nontype_argument (tree type, tree expr)
4324 /* Detect immediately string literals as invalid non-type argument.
4325 This special-case is not needed for correctness (we would easily
4326 catch this later), but only to provide better diagnostic for this
4327 common user mistake. As suggested by DR 100, we do not mention
4328 linkage issues in the diagnostic as this is not the point. */
4329 if (TREE_CODE (expr) == STRING_CST)
4331 error ("%qE is not a valid template argument for type %qT "
4332 "because string literals can never be used in this context",
4337 /* If we are in a template, EXPR may be non-dependent, but still
4338 have a syntactic, rather than semantic, form. For example, EXPR
4339 might be a SCOPE_REF, rather than the VAR_DECL to which the
4340 SCOPE_REF refers. Preserving the qualifying scope is necessary
4341 so that access checking can be performed when the template is
4342 instantiated -- but here we need the resolved form so that we can
4343 convert the argument. */
4344 expr = fold_non_dependent_expr (expr);
4345 if (error_operand_p (expr))
4346 return error_mark_node;
4347 expr_type = TREE_TYPE (expr);
4349 /* HACK: Due to double coercion, we can get a
4350 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
4351 which is the tree that we built on the first call (see
4352 below when coercing to reference to object or to reference to
4353 function). We just strip everything and get to the arg.
4354 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
4356 if (TREE_CODE (expr) == NOP_EXPR)
4358 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
4360 /* ??? Maybe we could use convert_from_reference here, but we
4361 would need to relax its constraints because the NOP_EXPR
4362 could actually change the type to something more cv-qualified,
4363 and this is not folded by convert_from_reference. */
4364 tree addr = TREE_OPERAND (expr, 0);
4365 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
4366 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
4367 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
4368 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4369 (TREE_TYPE (expr_type),
4370 TREE_TYPE (TREE_TYPE (addr))));
4372 expr = TREE_OPERAND (addr, 0);
4373 expr_type = TREE_TYPE (expr);
4376 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
4377 parameter is a pointer to object, through decay and
4378 qualification conversion. Let's strip everything. */
4379 else if (TYPE_PTROBV_P (type))
4382 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
4383 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
4384 /* Skip the ADDR_EXPR only if it is part of the decay for
4385 an array. Otherwise, it is part of the original argument
4386 in the source code. */
4387 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
4388 expr = TREE_OPERAND (expr, 0);
4389 expr_type = TREE_TYPE (expr);
4393 /* [temp.arg.nontype]/5, bullet 1
4395 For a non-type template-parameter of integral or enumeration type,
4396 integral promotions (_conv.prom_) and integral conversions
4397 (_conv.integral_) are applied. */
4398 if (INTEGRAL_TYPE_P (type))
4400 if (!INTEGRAL_TYPE_P (expr_type))
4401 return error_mark_node;
4403 expr = fold_decl_constant_value (expr);
4404 /* Notice that there are constant expressions like '4 % 0' which
4405 do not fold into integer constants. */
4406 if (TREE_CODE (expr) != INTEGER_CST)
4408 error ("%qE is not a valid template argument for type %qT "
4409 "because it is a non-constant expression", expr, type);
4413 /* At this point, an implicit conversion does what we want,
4414 because we already know that the expression is of integral
4416 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
4417 if (expr == error_mark_node)
4418 return error_mark_node;
4420 /* Conversion was allowed: fold it to a bare integer constant. */
4423 /* [temp.arg.nontype]/5, bullet 2
4425 For a non-type template-parameter of type pointer to object,
4426 qualification conversions (_conv.qual_) and the array-to-pointer
4427 conversion (_conv.array_) are applied. */
4428 else if (TYPE_PTROBV_P (type))
4430 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
4432 A template-argument for a non-type, non-template template-parameter
4433 shall be one of: [...]
4435 -- the name of a non-type template-parameter;
4436 -- the address of an object or function with external linkage, [...]
4437 expressed as "& id-expression" where the & is optional if the name
4438 refers to a function or array, or if the corresponding
4439 template-parameter is a reference.
4441 Here, we do not care about functions, as they are invalid anyway
4442 for a parameter of type pointer-to-object. */
4444 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
4445 /* Non-type template parameters are OK. */
4447 else if (TREE_CODE (expr) != ADDR_EXPR
4448 && TREE_CODE (expr_type) != ARRAY_TYPE)
4450 if (TREE_CODE (expr) == VAR_DECL)
4452 error ("%qD is not a valid template argument "
4453 "because %qD is a variable, not the address of "
4458 /* Other values, like integer constants, might be valid
4459 non-type arguments of some other type. */
4460 return error_mark_node;
4466 decl = ((TREE_CODE (expr) == ADDR_EXPR)
4467 ? TREE_OPERAND (expr, 0) : expr);
4468 if (TREE_CODE (decl) != VAR_DECL)
4470 error ("%qE is not a valid template argument of type %qT "
4471 "because %qE is not a variable",
4475 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
4477 error ("%qE is not a valid template argument of type %qT "
4478 "because %qD does not have external linkage",
4484 expr = decay_conversion (expr);
4485 if (expr == error_mark_node)
4486 return error_mark_node;
4488 expr = perform_qualification_conversions (type, expr);
4489 if (expr == error_mark_node)
4490 return error_mark_node;
4492 /* [temp.arg.nontype]/5, bullet 3
4494 For a non-type template-parameter of type reference to object, no
4495 conversions apply. The type referred to by the reference may be more
4496 cv-qualified than the (otherwise identical) type of the
4497 template-argument. The template-parameter is bound directly to the
4498 template-argument, which must be an lvalue. */
4499 else if (TYPE_REF_OBJ_P (type))
4501 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
4503 return error_mark_node;
4505 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
4507 error ("%qE is not a valid template argument for type %qT "
4508 "because of conflicts in cv-qualification", expr, type);
4512 if (!real_lvalue_p (expr))
4514 error ("%qE is not a valid template argument for type %qT "
4515 "because it is not an lvalue", expr, type);
4519 /* [temp.arg.nontype]/1
4521 A template-argument for a non-type, non-template template-parameter
4522 shall be one of: [...]
4524 -- the address of an object or function with external linkage. */
4525 if (!DECL_EXTERNAL_LINKAGE_P (expr))
4527 error ("%qE is not a valid template argument for type %qT "
4528 "because object %qD has not external linkage",
4533 expr = build_nop (type, build_address (expr));
4535 /* [temp.arg.nontype]/5, bullet 4
4537 For a non-type template-parameter of type pointer to function, only
4538 the function-to-pointer conversion (_conv.func_) is applied. If the
4539 template-argument represents a set of overloaded functions (or a
4540 pointer to such), the matching function is selected from the set
4542 else if (TYPE_PTRFN_P (type))
4544 /* If the argument is a template-id, we might not have enough
4545 context information to decay the pointer. */
4546 if (!type_unknown_p (expr_type))
4548 expr = decay_conversion (expr);
4549 if (expr == error_mark_node)
4550 return error_mark_node;
4553 expr = convert_nontype_argument_function (type, expr);
4554 if (!expr || expr == error_mark_node)
4557 /* [temp.arg.nontype]/5, bullet 5
4559 For a non-type template-parameter of type reference to function, no
4560 conversions apply. If the template-argument represents a set of
4561 overloaded functions, the matching function is selected from the set
4563 else if (TYPE_REFFN_P (type))
4565 if (TREE_CODE (expr) == ADDR_EXPR)
4567 error ("%qE is not a valid template argument for type %qT "
4568 "because it is a pointer", expr, type);
4569 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
4573 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
4574 if (!expr || expr == error_mark_node)
4577 expr = build_nop (type, build_address (expr));
4579 /* [temp.arg.nontype]/5, bullet 6
4581 For a non-type template-parameter of type pointer to member function,
4582 no conversions apply. If the template-argument represents a set of
4583 overloaded member functions, the matching member function is selected
4584 from the set (_over.over_). */
4585 else if (TYPE_PTRMEMFUNC_P (type))
4587 expr = instantiate_type (type, expr, tf_none);
4588 if (expr == error_mark_node)
4589 return error_mark_node;
4591 /* There is no way to disable standard conversions in
4592 resolve_address_of_overloaded_function (called by
4593 instantiate_type). It is possible that the call succeeded by
4594 converting &B::I to &D::I (where B is a base of D), so we need
4595 to reject this conversion here.
4597 Actually, even if there was a way to disable standard conversions,
4598 it would still be better to reject them here so that we can
4599 provide a superior diagnostic. */
4600 if (!same_type_p (TREE_TYPE (expr), type))
4602 /* Make sure we are just one standard conversion off. */
4603 gcc_assert (can_convert (type, TREE_TYPE (expr)));
4604 error ("%qE is not a valid template argument for type %qT "
4605 "because it is of type %qT", expr, type,
4607 inform ("standard conversions are not allowed in this context");
4611 /* [temp.arg.nontype]/5, bullet 7
4613 For a non-type template-parameter of type pointer to data member,
4614 qualification conversions (_conv.qual_) are applied. */
4615 else if (TYPE_PTRMEM_P (type))
4617 expr = perform_qualification_conversions (type, expr);
4618 if (expr == error_mark_node)
4621 /* A template non-type parameter must be one of the above. */
4625 /* Sanity check: did we actually convert the argument to the
4627 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
4631 /* Subroutine of coerce_template_template_parms, which returns 1 if
4632 PARM_PARM and ARG_PARM match using the rule for the template
4633 parameters of template template parameters. Both PARM and ARG are
4634 template parameters; the rest of the arguments are the same as for
4635 coerce_template_template_parms.
4638 coerce_template_template_parm (tree parm,
4640 tsubst_flags_t complain,
4644 if (arg == NULL_TREE || arg == error_mark_node
4645 || parm == NULL_TREE || parm == error_mark_node)
4648 if (TREE_CODE (arg) != TREE_CODE (parm))
4651 switch (TREE_CODE (parm))
4654 /* We encounter instantiations of templates like
4655 template <template <template <class> class> class TT>
4658 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
4659 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
4661 if (!coerce_template_template_parms
4662 (parmparm, argparm, complain, in_decl, outer_args))
4668 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
4669 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
4670 /* Argument is a parameter pack but parameter is not. */
4675 /* The tsubst call is used to handle cases such as
4677 template <int> class C {};
4678 template <class T, template <T> class TT> class D {};
4681 i.e. the parameter list of TT depends on earlier parameters. */
4682 if (!dependent_type_p (TREE_TYPE (arg))
4684 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
4688 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
4689 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
4690 /* Argument is a parameter pack but parameter is not. */
4703 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
4704 template template parameters. Both PARM_PARMS and ARG_PARMS are
4705 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
4708 Consider the example:
4709 template <class T> class A;
4710 template<template <class U> class TT> class B;
4712 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
4713 the parameters to A, and OUTER_ARGS contains A. */
4716 coerce_template_template_parms (tree parm_parms,
4718 tsubst_flags_t complain,
4722 int nparms, nargs, i;
4726 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
4727 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
4729 nparms = TREE_VEC_LENGTH (parm_parms);
4730 nargs = TREE_VEC_LENGTH (arg_parms);
4732 /* Determine whether we have a parameter pack at the end of the
4733 template template parameter's template parameter list. */
4734 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
4736 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
4738 switch (TREE_CODE (parm))
4742 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
4747 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
4757 && !(variadic_p && nargs >= nparms - 1))
4760 /* Check all of the template parameters except the parameter pack at
4761 the end (if any). */
4762 for (i = 0; i < nparms - variadic_p; ++i)
4764 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
4765 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
4768 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
4769 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
4771 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
4779 /* Check each of the template parameters in the template
4780 argument against the template parameter pack at the end of
4781 the template template parameter. */
4782 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
4785 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
4787 for (; i < nargs; ++i)
4789 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
4792 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
4794 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
4803 /* Verifies that the deduced template arguments (in TARGS) for the
4804 template template parameters (in TPARMS) represent valid bindings,
4805 by comparing the template parameter list of each template argument
4806 to the template parameter list of its corresponding template
4807 template parameter, in accordance with DR150. This
4808 routine can only be called after all template arguments have been
4809 deduced. It will return TRUE if all of the template template
4810 parameter bindings are okay, FALSE otherwise. */
4812 template_template_parm_bindings_ok_p (tree tparms, tree targs)
4814 int i, ntparms = TREE_VEC_LENGTH (tparms);
4817 /* We're dealing with template parms in this process. */
4818 ++processing_template_decl;
4820 targs = INNERMOST_TEMPLATE_ARGS (targs);
4822 for (i = 0; i < ntparms; ++i)
4824 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
4825 tree targ = TREE_VEC_ELT (targs, i);
4827 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
4829 tree packed_args = NULL_TREE;
4832 if (ARGUMENT_PACK_P (targ))
4834 /* Look inside the argument pack. */
4835 packed_args = ARGUMENT_PACK_ARGS (targ);
4836 len = TREE_VEC_LENGTH (packed_args);
4839 for (idx = 0; idx < len; ++idx)
4841 tree targ_parms = NULL_TREE;
4844 /* Extract the next argument from the argument
4846 targ = TREE_VEC_ELT (packed_args, idx);
4848 if (PACK_EXPANSION_P (targ))
4849 /* Look at the pattern of the pack expansion. */
4850 targ = PACK_EXPANSION_PATTERN (targ);
4852 /* Extract the template parameters from the template
4854 if (TREE_CODE (targ) == TEMPLATE_DECL)
4855 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
4856 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
4857 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
4859 /* Verify that we can coerce the template template
4860 parameters from the template argument to the template
4861 parameter. This requires an exact match. */
4863 && !coerce_template_template_parms
4864 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
4879 --processing_template_decl;
4883 /* Convert the indicated template ARG as necessary to match the
4884 indicated template PARM. Returns the converted ARG, or
4885 error_mark_node if the conversion was unsuccessful. Error and
4886 warning messages are issued under control of COMPLAIN. This
4887 conversion is for the Ith parameter in the parameter list. ARGS is
4888 the full set of template arguments deduced so far. */
4891 convert_template_argument (tree parm,
4894 tsubst_flags_t complain,
4900 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
4902 if (TREE_CODE (arg) == TREE_LIST
4903 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
4905 /* The template argument was the name of some
4906 member function. That's usually
4907 invalid, but static members are OK. In any
4908 case, grab the underlying fields/functions
4909 and issue an error later if required. */
4910 orig_arg = TREE_VALUE (arg);
4911 TREE_TYPE (arg) = unknown_type_node;
4916 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
4917 requires_type = (TREE_CODE (parm) == TYPE_DECL
4918 || requires_tmpl_type);
4920 /* When determining whether an argument pack expansion is a template,
4921 look at the pattern. */
4922 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
4923 arg = PACK_EXPANSION_PATTERN (arg);
4926 ((TREE_CODE (arg) == TEMPLATE_DECL
4927 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
4928 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
4929 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
4932 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
4933 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
4934 arg = TYPE_STUB_DECL (arg);
4936 is_type = TYPE_P (arg) || is_tmpl_type;
4938 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
4939 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
4941 permerror ("to refer to a type member of a template parameter, "
4942 "use %<typename %E%>", orig_arg);
4944 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
4945 TREE_OPERAND (arg, 1),
4947 complain & tf_error);
4951 if (is_type != requires_type)
4955 if (complain & tf_error)
4957 error ("type/value mismatch at argument %d in template "
4958 "parameter list for %qD",
4961 error (" expected a constant of type %qT, got %qT",
4963 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
4964 else if (requires_tmpl_type)
4965 error (" expected a class template, got %qE", orig_arg);
4967 error (" expected a type, got %qE", orig_arg);
4970 return error_mark_node;
4972 if (is_tmpl_type ^ requires_tmpl_type)
4974 if (in_decl && (complain & tf_error))
4976 error ("type/value mismatch at argument %d in template "
4977 "parameter list for %qD",
4980 error (" expected a type, got %qT", DECL_NAME (arg));
4982 error (" expected a class template, got %qT", orig_arg);
4984 return error_mark_node;
4989 if (requires_tmpl_type)
4991 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
4992 /* The number of argument required is not known yet.
4993 Just accept it for now. */
4994 val = TREE_TYPE (arg);
4997 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5000 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5002 if (coerce_template_template_parms (parmparm, argparm,
5008 /* TEMPLATE_TEMPLATE_PARM node is preferred over
5010 if (val != error_mark_node)
5012 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
5013 val = TREE_TYPE (val);
5014 else if (TREE_CODE (val) == TYPE_PACK_EXPANSION
5015 && DECL_TEMPLATE_TEMPLATE_PARM_P (arg))
5017 val = TREE_TYPE (arg);
5018 val = make_pack_expansion (val);
5024 if (in_decl && (complain & tf_error))
5026 error ("type/value mismatch at argument %d in "
5027 "template parameter list for %qD",
5029 error (" expected a template of type %qD, got %qD",
5033 val = error_mark_node;
5039 /* We only form one instance of each template specialization.
5040 Therefore, if we use a non-canonical variant (i.e., a
5041 typedef), any future messages referring to the type will use
5042 the typedef, which is confusing if those future uses do not
5043 themselves also use the typedef. */
5045 val = canonical_type_variant (val);
5049 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
5051 if (invalid_nontype_parm_type_p (t, complain))
5052 return error_mark_node;
5054 if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
5055 /* We used to call digest_init here. However, digest_init
5056 will report errors, which we don't want when complain
5057 is zero. More importantly, digest_init will try too
5058 hard to convert things: for example, `0' should not be
5059 converted to pointer type at this point according to
5060 the standard. Accepting this is not merely an
5061 extension, since deciding whether or not these
5062 conversions can occur is part of determining which
5063 function template to call, or whether a given explicit
5064 argument specification is valid. */
5065 val = convert_nontype_argument (t, orig_arg);
5069 if (val == NULL_TREE)
5070 val = error_mark_node;
5071 else if (val == error_mark_node && (complain & tf_error))
5072 error ("could not convert template argument %qE to %qT", orig_arg, t);
5078 /* Coerces the remaining template arguments in INNER_ARGS (from
5079 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
5080 Returns the coerced argument pack. PARM_IDX is the position of this
5081 parameter in the template parameter list. ARGS is the original
5082 template argument list. */
5084 coerce_template_parameter_pack (tree parms,
5092 tsubst_flags_t complain)
5094 tree parm = TREE_VEC_ELT (parms, parm_idx);
5095 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5098 tree packed_types = NULL_TREE;
5100 if (arg_idx > nargs)
5103 packed_args = make_tree_vec (nargs - arg_idx);
5105 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
5106 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
5108 /* When the template parameter is a non-type template
5109 parameter pack whose type uses parameter packs, we need
5110 to look at each of the template arguments
5111 separately. Build a vector of the types for these
5112 non-type template parameters in PACKED_TYPES. */
5114 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
5115 packed_types = tsubst_pack_expansion (expansion, args,
5118 if (packed_types == error_mark_node)
5119 return error_mark_node;
5121 /* Check that we have the right number of arguments. */
5123 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
5124 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
5127 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
5128 error ("wrong number of template arguments (%d, should be %d)",
5129 nargs, needed_parms);
5130 return error_mark_node;
5133 /* If we aren't able to check the actual arguments now
5134 (because they haven't been expanded yet), we can at least
5135 verify that all of the types used for the non-type
5136 template parameter pack are, in fact, valid for non-type
5137 template parameters. */
5139 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
5141 int j, len = TREE_VEC_LENGTH (packed_types);
5142 for (j = 0; j < len; ++j)
5144 tree t = TREE_VEC_ELT (packed_types, j);
5145 if (invalid_nontype_parm_type_p (t, complain))
5146 return error_mark_node;
5151 /* Convert the remaining arguments, which will be a part of the
5152 parameter pack "parm". */
5153 for (; arg_idx < nargs; ++arg_idx)
5155 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
5156 tree actual_parm = TREE_VALUE (parm);
5158 if (packed_types && !PACK_EXPANSION_P (arg))
5160 /* When we have a vector of types (corresponding to the
5161 non-type template parameter pack that uses parameter
5162 packs in its type, as mention above), and the
5163 argument is not an expansion (which expands to a
5164 currently unknown number of arguments), clone the
5165 parm and give it the next type in PACKED_TYPES. */
5166 actual_parm = copy_node (actual_parm);
5167 TREE_TYPE (actual_parm) =
5168 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
5171 if (arg != error_mark_node)
5172 arg = convert_template_argument (actual_parm,
5173 arg, new_args, complain, parm_idx,
5175 if (arg == error_mark_node)
5177 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
5180 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
5181 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
5182 argument_pack = make_node (TYPE_ARGUMENT_PACK);
5185 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
5186 TREE_TYPE (argument_pack)
5187 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
5188 TREE_CONSTANT (argument_pack) = 1;
5191 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
5192 return argument_pack;
5195 /* Convert all template arguments to their appropriate types, and
5196 return a vector containing the innermost resulting template
5197 arguments. If any error occurs, return error_mark_node. Error and
5198 warning messages are issued under control of COMPLAIN.
5200 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
5201 for arguments not specified in ARGS. Otherwise, if
5202 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
5203 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
5204 USE_DEFAULT_ARGS is false, then all arguments must be specified in
5208 coerce_template_parms (tree parms,
5211 tsubst_flags_t complain,
5212 bool require_all_args,
5213 bool use_default_args)
5215 int nparms, nargs, parm_idx, arg_idx, lost = 0;
5218 tree new_inner_args;
5219 bool saved_skip_evaluation;
5221 /* When used as a boolean value, indicates whether this is a
5222 variadic template parameter list. Since it's an int, we can also
5223 subtract it from nparms to get the number of non-variadic
5228 = expand_template_argument_pack (INNERMOST_TEMPLATE_ARGS (args));
5230 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5231 nparms = TREE_VEC_LENGTH (parms);
5233 /* Determine if there are any parameter packs. */
5234 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
5236 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
5237 if (template_parameter_pack_p (tparm))
5244 if ((nargs > nparms - variadic_p && !variadic_p)
5245 || (nargs < nparms - variadic_p
5247 && (!use_default_args
5248 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
5249 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
5251 if (complain & tf_error)
5253 const char *or_more = "";
5256 or_more = " or more";
5260 error ("wrong number of template arguments (%d, should be %d%s)",
5261 nargs, nparms, or_more);
5264 error ("provided for %q+D", in_decl);
5267 return error_mark_node;
5270 /* We need to evaluate the template arguments, even though this
5271 template-id may be nested within a "sizeof". */
5272 saved_skip_evaluation = skip_evaluation;
5273 skip_evaluation = false;
5274 new_inner_args = make_tree_vec (nparms);
5275 new_args = add_outermost_template_args (args, new_inner_args);
5276 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
5281 /* Get the Ith template parameter. */
5282 parm = TREE_VEC_ELT (parms, parm_idx);
5284 if (parm == error_mark_node)
5286 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
5290 /* Calculate the next argument. */
5291 if (template_parameter_pack_p (TREE_VALUE (parm)))
5293 /* All remaining arguments will be placed in the
5294 template parameter pack PARM. */
5295 arg = coerce_template_parameter_pack (parms, parm_idx, args,
5296 inner_args, arg_idx,
5300 /* Store this argument. */
5301 if (arg == error_mark_node)
5303 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
5305 /* We are done with all of the arguments. */
5310 else if (arg_idx < nargs)
5312 arg = TREE_VEC_ELT (inner_args, arg_idx);
5314 if (arg && PACK_EXPANSION_P (arg))
5316 if (complain & tf_error)
5318 /* If ARG is a pack expansion, but PARM is not a
5319 template parameter pack (if it were, we would have
5320 handled it above), we're trying to expand into a
5321 fixed-length argument list. */
5322 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
5323 error ("cannot expand %<%E%> into a fixed-length "
5324 "argument list", arg);
5326 error ("cannot expand %<%T%> into a fixed-length "
5327 "argument list", arg);
5329 return error_mark_node;
5332 else if (require_all_args)
5333 /* There must be a default arg in this case. */
5334 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
5339 if (arg == error_mark_node)
5341 if (complain & tf_error)
5342 error ("template argument %d is invalid", arg_idx + 1);
5345 /* This only occurs if there was an error in the template
5346 parameter list itself (which we would already have
5347 reported) that we are trying to recover from, e.g., a class
5348 template with a parameter list such as
5349 template<typename..., typename>. */
5350 return error_mark_node;
5352 arg = convert_template_argument (TREE_VALUE (parm),
5353 arg, new_args, complain,
5356 if (arg == error_mark_node)
5358 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
5360 skip_evaluation = saved_skip_evaluation;
5363 return error_mark_node;
5365 return new_inner_args;
5368 /* Returns 1 if template args OT and NT are equivalent. */
5371 template_args_equal (tree ot, tree nt)
5376 if (TREE_CODE (nt) == TREE_VEC)
5377 /* For member templates */
5378 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
5379 else if (PACK_EXPANSION_P (ot))
5380 return PACK_EXPANSION_P (nt)
5381 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
5382 PACK_EXPANSION_PATTERN (nt));
5383 else if (TYPE_P (nt))
5384 return TYPE_P (ot) && same_type_p (ot, nt);
5385 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
5388 return cp_tree_equal (ot, nt);
5391 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
5392 of template arguments. Returns 0 otherwise. */
5395 comp_template_args (tree oldargs, tree newargs)
5399 oldargs = expand_template_argument_pack (oldargs);
5400 newargs = expand_template_argument_pack (newargs);
5402 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
5405 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
5407 tree nt = TREE_VEC_ELT (newargs, i);
5408 tree ot = TREE_VEC_ELT (oldargs, i);
5410 if (! template_args_equal (ot, nt))
5417 add_pending_template (tree d)
5419 tree ti = (TYPE_P (d)
5420 ? CLASSTYPE_TEMPLATE_INFO (d)
5421 : DECL_TEMPLATE_INFO (d));
5422 struct pending_template *pt;
5425 if (TI_PENDING_TEMPLATE_FLAG (ti))
5428 /* We are called both from instantiate_decl, where we've already had a
5429 tinst_level pushed, and instantiate_template, where we haven't.
5431 level = !current_tinst_level || current_tinst_level->decl != d;
5434 push_tinst_level (d);
5436 pt = GGC_NEW (struct pending_template);
5438 pt->tinst = current_tinst_level;
5439 if (last_pending_template)
5440 last_pending_template->next = pt;
5442 pending_templates = pt;
5444 last_pending_template = pt;
5446 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
5453 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
5454 ARGLIST. Valid choices for FNS are given in the cp-tree.def
5455 documentation for TEMPLATE_ID_EXPR. */
5458 lookup_template_function (tree fns, tree arglist)
5462 if (fns == error_mark_node || arglist == error_mark_node)
5463 return error_mark_node;
5465 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
5466 gcc_assert (fns && (is_overloaded_fn (fns)
5467 || TREE_CODE (fns) == IDENTIFIER_NODE));
5469 if (BASELINK_P (fns))
5471 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
5473 BASELINK_FUNCTIONS (fns),
5478 type = TREE_TYPE (fns);
5479 if (TREE_CODE (fns) == OVERLOAD || !type)
5480 type = unknown_type_node;
5482 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
5485 /* Within the scope of a template class S<T>, the name S gets bound
5486 (in build_self_reference) to a TYPE_DECL for the class, not a
5487 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
5488 or one of its enclosing classes, and that type is a template,
5489 return the associated TEMPLATE_DECL. Otherwise, the original
5490 DECL is returned. */
5493 maybe_get_template_decl_from_type_decl (tree decl)
5495 return (decl != NULL_TREE
5496 && TREE_CODE (decl) == TYPE_DECL
5497 && DECL_ARTIFICIAL (decl)
5498 && CLASS_TYPE_P (TREE_TYPE (decl))
5499 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
5500 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
5503 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
5504 parameters, find the desired type.
5506 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
5508 IN_DECL, if non-NULL, is the template declaration we are trying to
5511 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
5512 the class we are looking up.
5514 Issue error and warning messages under control of COMPLAIN.
5516 If the template class is really a local class in a template
5517 function, then the FUNCTION_CONTEXT is the function in which it is
5520 ??? Note that this function is currently called *twice* for each
5521 template-id: the first time from the parser, while creating the
5522 incomplete type (finish_template_type), and the second type during the
5523 real instantiation (instantiate_template_class). This is surely something
5524 that we want to avoid. It also causes some problems with argument
5525 coercion (see convert_nontype_argument for more information on this). */
5528 lookup_template_class (tree d1,
5533 tsubst_flags_t complain)
5535 tree templ = NULL_TREE, parmlist;
5538 timevar_push (TV_NAME_LOOKUP);
5540 if (TREE_CODE (d1) == IDENTIFIER_NODE)
5542 tree value = innermost_non_namespace_value (d1);
5543 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
5548 push_decl_namespace (context);
5549 templ = lookup_name (d1);
5550 templ = maybe_get_template_decl_from_type_decl (templ);
5552 pop_decl_namespace ();
5555 context = DECL_CONTEXT (templ);
5557 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
5559 tree type = TREE_TYPE (d1);
5561 /* If we are declaring a constructor, say A<T>::A<T>, we will get
5562 an implicit typename for the second A. Deal with it. */
5563 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
5564 type = TREE_TYPE (type);
5566 if (CLASSTYPE_TEMPLATE_INFO (type))
5568 templ = CLASSTYPE_TI_TEMPLATE (type);
5569 d1 = DECL_NAME (templ);
5572 else if (TREE_CODE (d1) == ENUMERAL_TYPE
5573 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
5575 templ = TYPE_TI_TEMPLATE (d1);
5576 d1 = DECL_NAME (templ);
5578 else if (TREE_CODE (d1) == TEMPLATE_DECL
5579 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
5582 d1 = DECL_NAME (templ);
5583 context = DECL_CONTEXT (templ);
5586 /* Issue an error message if we didn't find a template. */
5589 if (complain & tf_error)
5590 error ("%qT is not a template", d1);
5591 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5594 if (TREE_CODE (templ) != TEMPLATE_DECL
5595 /* Make sure it's a user visible template, if it was named by
5597 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
5598 && !PRIMARY_TEMPLATE_P (templ)))
5600 if (complain & tf_error)
5602 error ("non-template type %qT used as a template", d1);
5604 error ("for template declaration %q+D", in_decl);
5606 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5609 complain &= ~tf_user;
5611 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
5613 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
5614 template arguments */
5620 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
5622 /* Consider an example where a template template parameter declared as
5624 template <class T, class U = std::allocator<T> > class TT
5626 The template parameter level of T and U are one level larger than
5627 of TT. To proper process the default argument of U, say when an
5628 instantiation `TT<int>' is seen, we need to build the full
5629 arguments containing {int} as the innermost level. Outer levels,
5630 available when not appearing as default template argument, can be
5631 obtained from the arguments of the enclosing template.
5633 Suppose that TT is later substituted with std::vector. The above
5634 instantiation is `TT<int, std::allocator<T> >' with TT at
5635 level 1, and T at level 2, while the template arguments at level 1
5636 becomes {std::vector} and the inner level 2 is {int}. */
5638 outer = DECL_CONTEXT (templ);
5640 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
5641 else if (current_template_parms)
5642 /* This is an argument of the current template, so we haven't set
5643 DECL_CONTEXT yet. */
5644 outer = current_template_args ();
5647 arglist = add_to_template_args (outer, arglist);
5649 arglist2 = coerce_template_parms (parmlist, arglist, templ,
5651 /*require_all_args=*/true,
5652 /*use_default_args=*/true);
5653 if (arglist2 == error_mark_node
5654 || (!uses_template_parms (arglist2)
5655 && check_instantiated_args (templ, arglist2, complain)))
5656 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5658 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
5659 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
5663 tree template_type = TREE_TYPE (templ);
5666 tree found = NULL_TREE;
5669 int is_partial_instantiation;
5671 gen_tmpl = most_general_template (templ);
5672 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
5673 parm_depth = TMPL_PARMS_DEPTH (parmlist);
5674 arg_depth = TMPL_ARGS_DEPTH (arglist);
5676 if (arg_depth == 1 && parm_depth > 1)
5678 /* We've been given an incomplete set of template arguments.
5681 template <class T> struct S1 {
5682 template <class U> struct S2 {};
5683 template <class U> struct S2<U*> {};
5686 we will be called with an ARGLIST of `U*', but the
5687 TEMPLATE will be `template <class T> template
5688 <class U> struct S1<T>::S2'. We must fill in the missing
5691 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
5693 arg_depth = TMPL_ARGS_DEPTH (arglist);
5696 /* Now we should have enough arguments. */
5697 gcc_assert (parm_depth == arg_depth);
5699 /* From here on, we're only interested in the most general
5703 /* Calculate the BOUND_ARGS. These will be the args that are
5704 actually tsubst'd into the definition to create the
5708 /* We have multiple levels of arguments to coerce, at once. */
5710 int saved_depth = TMPL_ARGS_DEPTH (arglist);
5712 tree bound_args = make_tree_vec (parm_depth);
5714 for (i = saved_depth,
5715 t = DECL_TEMPLATE_PARMS (templ);
5716 i > 0 && t != NULL_TREE;
5717 --i, t = TREE_CHAIN (t))
5719 tree a = coerce_template_parms (TREE_VALUE (t),
5722 /*require_all_args=*/true,
5723 /*use_default_args=*/true);
5725 /* Don't process further if one of the levels fails. */
5726 if (a == error_mark_node)
5728 /* Restore the ARGLIST to its full size. */
5729 TREE_VEC_LENGTH (arglist) = saved_depth;
5730 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5733 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
5735 /* We temporarily reduce the length of the ARGLIST so
5736 that coerce_template_parms will see only the arguments
5737 corresponding to the template parameters it is
5739 TREE_VEC_LENGTH (arglist)--;
5742 /* Restore the ARGLIST to its full size. */
5743 TREE_VEC_LENGTH (arglist) = saved_depth;
5745 arglist = bound_args;
5749 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
5750 INNERMOST_TEMPLATE_ARGS (arglist),
5753 /*require_all_args=*/true,
5754 /*use_default_args=*/true);
5756 if (arglist == error_mark_node)
5757 /* We were unable to bind the arguments. */
5758 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5760 /* In the scope of a template class, explicit references to the
5761 template class refer to the type of the template, not any
5762 instantiation of it. For example, in:
5764 template <class T> class C { void f(C<T>); }
5766 the `C<T>' is just the same as `C'. Outside of the
5767 class, however, such a reference is an instantiation. */
5768 if (comp_template_args (TYPE_TI_ARGS (template_type),
5771 found = template_type;
5773 if (!entering_scope && PRIMARY_TEMPLATE_P (templ))
5777 for (ctx = current_class_type;
5778 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
5780 ? TYPE_CONTEXT (ctx)
5781 : DECL_CONTEXT (ctx)))
5782 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
5785 /* We're not in the scope of the class, so the
5786 TEMPLATE_TYPE is not the type we want after all. */
5792 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
5794 /* If we already have this specialization, return it. */
5795 found = retrieve_specialization (templ, arglist,
5796 /*class_specializations_p=*/false);
5798 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
5800 /* This type is a "partial instantiation" if any of the template
5801 arguments still involve template parameters. Note that we set
5802 IS_PARTIAL_INSTANTIATION for partial specializations as
5804 is_partial_instantiation = uses_template_parms (arglist);
5806 /* If the deduced arguments are invalid, then the binding
5808 if (!is_partial_instantiation
5809 && check_instantiated_args (templ,
5810 INNERMOST_TEMPLATE_ARGS (arglist),
5812 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5814 if (!is_partial_instantiation
5815 && !PRIMARY_TEMPLATE_P (templ)
5816 && TREE_CODE (CP_DECL_CONTEXT (templ)) == NAMESPACE_DECL)
5818 found = xref_tag_from_type (TREE_TYPE (templ),
5820 /*tag_scope=*/ts_global);
5821 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
5824 context = tsubst (DECL_CONTEXT (templ), arglist,
5827 context = global_namespace;
5829 /* Create the type. */
5830 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
5832 if (!is_partial_instantiation)
5834 set_current_access_from_decl (TYPE_NAME (template_type));
5835 t = start_enum (TYPE_IDENTIFIER (template_type));
5838 /* We don't want to call start_enum for this type, since
5839 the values for the enumeration constants may involve
5840 template parameters. And, no one should be interested
5841 in the enumeration constants for such a type. */
5842 t = make_node (ENUMERAL_TYPE);
5846 t = make_class_type (TREE_CODE (template_type));
5847 CLASSTYPE_DECLARED_CLASS (t)
5848 = CLASSTYPE_DECLARED_CLASS (template_type);
5849 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
5850 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
5852 /* A local class. Make sure the decl gets registered properly. */
5853 if (context == current_function_decl)
5854 pushtag (DECL_NAME (templ), t, /*tag_scope=*/ts_current);
5856 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
5857 /* This instantiation is another name for the primary
5858 template type. Set the TYPE_CANONICAL field
5860 TYPE_CANONICAL (t) = template_type;
5861 else if (any_template_arguments_need_structural_equality_p (arglist))
5862 /* Some of the template arguments require structural
5863 equality testing, so this template class requires
5864 structural equality testing. */
5865 SET_TYPE_STRUCTURAL_EQUALITY (t);
5868 /* If we called start_enum or pushtag above, this information
5869 will already be set up. */
5872 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
5874 type_decl = create_implicit_typedef (DECL_NAME (templ), t);
5875 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
5876 TYPE_STUB_DECL (t) = type_decl;
5877 DECL_SOURCE_LOCATION (type_decl)
5878 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
5881 type_decl = TYPE_NAME (t);
5883 TREE_PRIVATE (type_decl)
5884 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
5885 TREE_PROTECTED (type_decl)
5886 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
5887 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
5889 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
5890 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
5893 /* Set up the template information. We have to figure out which
5894 template is the immediate parent if this is a full
5896 if (parm_depth == 1 || is_partial_instantiation
5897 || !PRIMARY_TEMPLATE_P (templ))
5898 /* This case is easy; there are no member templates involved. */
5902 /* This is a full instantiation of a member template. Look
5903 for a partial instantiation of which this is an instance. */
5905 for (found = DECL_TEMPLATE_INSTANTIATIONS (templ);
5906 found; found = TREE_CHAIN (found))
5909 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
5911 /* We only want partial instantiations, here, not
5912 specializations or full instantiations. */
5913 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
5914 || !uses_template_parms (TREE_VALUE (found)))
5917 /* Temporarily reduce by one the number of levels in the
5918 ARGLIST and in FOUND so as to avoid comparing the
5919 last set of arguments. */
5920 TREE_VEC_LENGTH (arglist)--;
5921 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
5923 /* See if the arguments match. If they do, then TMPL is
5924 the partial instantiation we want. */
5925 success = comp_template_args (TREE_PURPOSE (found), arglist);
5927 /* Restore the argument vectors to their full size. */
5928 TREE_VEC_LENGTH (arglist)++;
5929 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
5940 /* There was no partial instantiation. This happens
5941 where C<T> is a member template of A<T> and it's used
5944 template <typename T> struct B { A<T>::C<int> m; };
5947 Create the partial instantiation.
5949 TREE_VEC_LENGTH (arglist)--;
5950 found = tsubst (templ, arglist, complain, NULL_TREE);
5951 TREE_VEC_LENGTH (arglist)++;
5955 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
5956 DECL_TEMPLATE_INSTANTIATIONS (templ)
5957 = tree_cons (arglist, t,
5958 DECL_TEMPLATE_INSTANTIATIONS (templ));
5960 if (TREE_CODE (t) == ENUMERAL_TYPE
5961 && !is_partial_instantiation)
5962 /* Now that the type has been registered on the instantiations
5963 list, we set up the enumerators. Because the enumeration
5964 constants may involve the enumeration type itself, we make
5965 sure to register the type first, and then create the
5966 constants. That way, doing tsubst_expr for the enumeration
5967 constants won't result in recursive calls here; we'll find
5968 the instantiation and exit above. */
5969 tsubst_enum (template_type, t, arglist);
5971 if (is_partial_instantiation)
5972 /* If the type makes use of template parameters, the
5973 code that generates debugging information will crash. */
5974 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
5976 /* Possibly limit visibility based on template args. */
5977 TREE_PUBLIC (type_decl) = 1;
5978 determine_visibility (type_decl);
5980 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
5982 timevar_pop (TV_NAME_LOOKUP);
5989 /* True when we should also visit template parameters that occur in
5990 non-deduced contexts. */
5991 bool include_nondeduced_p;
5992 struct pointer_set_t *visited;
5995 /* Called from for_each_template_parm via walk_tree. */
5998 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
6001 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
6002 tree_fn_t fn = pfd->fn;
6003 void *data = pfd->data;
6006 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
6007 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
6008 pfd->include_nondeduced_p))
6009 return error_mark_node;
6011 switch (TREE_CODE (t))
6014 if (TYPE_PTRMEMFUNC_P (t))
6020 if (!TYPE_TEMPLATE_INFO (t))
6022 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
6023 fn, data, pfd->visited,
6024 pfd->include_nondeduced_p))
6025 return error_mark_node;
6029 if (for_each_template_parm (TYPE_MIN_VALUE (t),
6030 fn, data, pfd->visited,
6031 pfd->include_nondeduced_p)
6032 || for_each_template_parm (TYPE_MAX_VALUE (t),
6033 fn, data, pfd->visited,
6034 pfd->include_nondeduced_p))
6035 return error_mark_node;
6039 /* Since we're not going to walk subtrees, we have to do this
6041 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
6042 pfd->visited, pfd->include_nondeduced_p))
6043 return error_mark_node;
6047 /* Check the return type. */
6048 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6049 pfd->include_nondeduced_p))
6050 return error_mark_node;
6052 /* Check the parameter types. Since default arguments are not
6053 instantiated until they are needed, the TYPE_ARG_TYPES may
6054 contain expressions that involve template parameters. But,
6055 no-one should be looking at them yet. And, once they're
6056 instantiated, they don't contain template parameters, so
6057 there's no point in looking at them then, either. */
6061 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
6062 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
6063 pfd->visited, pfd->include_nondeduced_p))
6064 return error_mark_node;
6066 /* Since we've already handled the TYPE_ARG_TYPES, we don't
6067 want walk_tree walking into them itself. */
6073 if (pfd->include_nondeduced_p
6074 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
6076 pfd->include_nondeduced_p))
6077 return error_mark_node;
6082 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
6083 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
6084 pfd->visited, pfd->include_nondeduced_p))
6085 return error_mark_node;
6090 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
6091 && for_each_template_parm (DECL_INITIAL (t), fn, data,
6092 pfd->visited, pfd->include_nondeduced_p))
6093 return error_mark_node;
6094 if (DECL_CONTEXT (t)
6095 && pfd->include_nondeduced_p
6096 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
6097 pfd->visited, pfd->include_nondeduced_p))
6098 return error_mark_node;
6101 case BOUND_TEMPLATE_TEMPLATE_PARM:
6102 /* Record template parameters such as `T' inside `TT<T>'. */
6103 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
6104 pfd->include_nondeduced_p))
6105 return error_mark_node;
6108 case TEMPLATE_TEMPLATE_PARM:
6109 case TEMPLATE_TYPE_PARM:
6110 case TEMPLATE_PARM_INDEX:
6111 if (fn && (*fn)(t, data))
6112 return error_mark_node;
6114 return error_mark_node;
6118 /* A template template parameter is encountered. */
6119 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
6120 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6121 pfd->include_nondeduced_p))
6122 return error_mark_node;
6124 /* Already substituted template template parameter */
6130 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
6132 pfd->include_nondeduced_p))
6133 return error_mark_node;
6137 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
6138 && pfd->include_nondeduced_p
6139 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
6140 (TREE_TYPE (t)), fn, data,
6141 pfd->visited, pfd->include_nondeduced_p))
6142 return error_mark_node;
6147 /* If there's no type, then this thing must be some expression
6148 involving template parameters. */
6149 if (!fn && !TREE_TYPE (t))
6150 return error_mark_node;
6155 case REINTERPRET_CAST_EXPR:
6156 case CONST_CAST_EXPR:
6157 case STATIC_CAST_EXPR:
6158 case DYNAMIC_CAST_EXPR:
6162 case PSEUDO_DTOR_EXPR:
6164 return error_mark_node;
6171 /* We didn't find any template parameters we liked. */
6175 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
6176 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
6177 call FN with the parameter and the DATA.
6178 If FN returns nonzero, the iteration is terminated, and
6179 for_each_template_parm returns 1. Otherwise, the iteration
6180 continues. If FN never returns a nonzero value, the value
6181 returned by for_each_template_parm is 0. If FN is NULL, it is
6182 considered to be the function which always returns 1.
6184 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
6185 parameters that occur in non-deduced contexts. When false, only
6186 visits those template parameters that can be deduced. */
6189 for_each_template_parm (tree t, tree_fn_t fn, void* data,
6190 struct pointer_set_t *visited,
6191 bool include_nondeduced_p)
6193 struct pair_fn_data pfd;
6199 pfd.include_nondeduced_p = include_nondeduced_p;
6201 /* Walk the tree. (Conceptually, we would like to walk without
6202 duplicates, but for_each_template_parm_r recursively calls
6203 for_each_template_parm, so we would need to reorganize a fair
6204 bit to use walk_tree_without_duplicates, so we keep our own
6207 pfd.visited = visited;
6209 pfd.visited = pointer_set_create ();
6210 result = cp_walk_tree (&t,
6211 for_each_template_parm_r,
6213 pfd.visited) != NULL_TREE;
6218 pointer_set_destroy (pfd.visited);
6225 /* Returns true if T depends on any template parameter. */
6228 uses_template_parms (tree t)
6231 int saved_processing_template_decl;
6233 saved_processing_template_decl = processing_template_decl;
6234 if (!saved_processing_template_decl)
6235 processing_template_decl = 1;
6237 dependent_p = dependent_type_p (t);
6238 else if (TREE_CODE (t) == TREE_VEC)
6239 dependent_p = any_dependent_template_arguments_p (t);
6240 else if (TREE_CODE (t) == TREE_LIST)
6241 dependent_p = (uses_template_parms (TREE_VALUE (t))
6242 || uses_template_parms (TREE_CHAIN (t)));
6243 else if (TREE_CODE (t) == TYPE_DECL)
6244 dependent_p = dependent_type_p (TREE_TYPE (t));
6247 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
6248 || TREE_CODE (t) == OVERLOAD
6249 || TREE_CODE (t) == BASELINK
6250 || TREE_CODE (t) == IDENTIFIER_NODE
6251 || TREE_CODE (t) == TRAIT_EXPR
6252 || CONSTANT_CLASS_P (t))
6253 dependent_p = (type_dependent_expression_p (t)
6254 || value_dependent_expression_p (t));
6257 gcc_assert (t == error_mark_node);
6258 dependent_p = false;
6261 processing_template_decl = saved_processing_template_decl;
6266 /* Returns true if T depends on any template parameter with level LEVEL. */
6269 uses_template_parms_level (tree t, int level)
6271 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
6272 /*include_nondeduced_p=*/true);
6275 static int tinst_depth;
6276 extern int max_tinst_depth;
6277 #ifdef GATHER_STATISTICS
6280 static int tinst_level_tick;
6281 static int last_template_error_tick;
6283 /* We're starting to instantiate D; record the template instantiation context
6284 for diagnostics and to restore it later. */
6287 push_tinst_level (tree d)
6289 struct tinst_level *new_level;
6291 if (tinst_depth >= max_tinst_depth)
6293 /* If the instantiation in question still has unbound template parms,
6294 we don't really care if we can't instantiate it, so just return.
6295 This happens with base instantiation for implicit `typename'. */
6296 if (uses_template_parms (d))
6299 last_template_error_tick = tinst_level_tick;
6300 error ("template instantiation depth exceeds maximum of %d (use "
6301 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
6302 max_tinst_depth, d);
6304 print_instantiation_context ();
6309 new_level = GGC_NEW (struct tinst_level);
6310 new_level->decl = d;
6311 new_level->locus = input_location;
6312 new_level->in_system_header_p = in_system_header;
6313 new_level->next = current_tinst_level;
6314 current_tinst_level = new_level;
6317 #ifdef GATHER_STATISTICS
6318 if (tinst_depth > depth_reached)
6319 depth_reached = tinst_depth;
6326 /* We're done instantiating this template; return to the instantiation
6330 pop_tinst_level (void)
6332 /* Restore the filename and line number stashed away when we started
6333 this instantiation. */
6334 input_location = current_tinst_level->locus;
6335 current_tinst_level = current_tinst_level->next;
6340 /* We're instantiating a deferred template; restore the template
6341 instantiation context in which the instantiation was requested, which
6342 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
6345 reopen_tinst_level (struct tinst_level *level)
6347 struct tinst_level *t;
6350 for (t = level; t; t = t->next)
6353 current_tinst_level = level;
6358 /* Returns the TINST_LEVEL which gives the original instantiation
6361 struct tinst_level *
6362 outermost_tinst_level (void)
6364 struct tinst_level *level = current_tinst_level;
6367 level = level->next;
6371 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
6372 vector of template arguments, as for tsubst.
6374 Returns an appropriate tsubst'd friend declaration. */
6377 tsubst_friend_function (tree decl, tree args)
6381 if (TREE_CODE (decl) == FUNCTION_DECL
6382 && DECL_TEMPLATE_INSTANTIATION (decl)
6383 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
6384 /* This was a friend declared with an explicit template
6385 argument list, e.g.:
6389 to indicate that f was a template instantiation, not a new
6390 function declaration. Now, we have to figure out what
6391 instantiation of what template. */
6393 tree template_id, arglist, fns;
6396 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
6398 /* Friend functions are looked up in the containing namespace scope.
6399 We must enter that scope, to avoid finding member functions of the
6400 current class with same name. */
6401 push_nested_namespace (ns);
6402 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
6403 tf_warning_or_error, NULL_TREE,
6404 /*integral_constant_expression_p=*/false);
6405 pop_nested_namespace (ns);
6406 arglist = tsubst (DECL_TI_ARGS (decl), args,
6407 tf_warning_or_error, NULL_TREE);
6408 template_id = lookup_template_function (fns, arglist);
6410 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6411 tmpl = determine_specialization (template_id, new_friend,
6413 /*need_member_template=*/0,
6414 TREE_VEC_LENGTH (args),
6416 return instantiate_template (tmpl, new_args, tf_error);
6419 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6421 /* The NEW_FRIEND will look like an instantiation, to the
6422 compiler, but is not an instantiation from the point of view of
6423 the language. For example, we might have had:
6425 template <class T> struct S {
6426 template <class U> friend void f(T, U);
6429 Then, in S<int>, template <class U> void f(int, U) is not an
6430 instantiation of anything. */
6431 if (new_friend == error_mark_node)
6432 return error_mark_node;
6434 DECL_USE_TEMPLATE (new_friend) = 0;
6435 if (TREE_CODE (decl) == TEMPLATE_DECL)
6437 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
6438 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
6439 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
6442 /* The mangled name for the NEW_FRIEND is incorrect. The function
6443 is not a template instantiation and should not be mangled like
6444 one. Therefore, we forget the mangling here; we'll recompute it
6445 later if we need it. */
6446 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
6448 SET_DECL_RTL (new_friend, NULL_RTX);
6449 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
6452 if (DECL_NAMESPACE_SCOPE_P (new_friend))
6455 tree new_friend_template_info;
6456 tree new_friend_result_template_info;
6458 int new_friend_is_defn;
6460 /* We must save some information from NEW_FRIEND before calling
6461 duplicate decls since that function will free NEW_FRIEND if
6463 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
6464 new_friend_is_defn =
6465 (DECL_INITIAL (DECL_TEMPLATE_RESULT
6466 (template_for_substitution (new_friend)))
6468 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
6470 /* This declaration is a `primary' template. */
6471 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
6473 new_friend_result_template_info
6474 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
6477 new_friend_result_template_info = NULL_TREE;
6479 /* Make the init_value nonzero so pushdecl knows this is a defn. */
6480 if (new_friend_is_defn)
6481 DECL_INITIAL (new_friend) = error_mark_node;
6483 /* Inside pushdecl_namespace_level, we will push into the
6484 current namespace. However, the friend function should go
6485 into the namespace of the template. */
6486 ns = decl_namespace_context (new_friend);
6487 push_nested_namespace (ns);
6488 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
6489 pop_nested_namespace (ns);
6491 if (old_decl == error_mark_node)
6492 return error_mark_node;
6494 if (old_decl != new_friend)
6496 /* This new friend declaration matched an existing
6497 declaration. For example, given:
6499 template <class T> void f(T);
6500 template <class U> class C {
6501 template <class T> friend void f(T) {}
6504 the friend declaration actually provides the definition
6505 of `f', once C has been instantiated for some type. So,
6506 old_decl will be the out-of-class template declaration,
6507 while new_friend is the in-class definition.
6509 But, if `f' was called before this point, the
6510 instantiation of `f' will have DECL_TI_ARGS corresponding
6511 to `T' but not to `U', references to which might appear
6512 in the definition of `f'. Previously, the most general
6513 template for an instantiation of `f' was the out-of-class
6514 version; now it is the in-class version. Therefore, we
6515 run through all specialization of `f', adding to their
6516 DECL_TI_ARGS appropriately. In particular, they need a
6517 new set of outer arguments, corresponding to the
6518 arguments for this class instantiation.
6520 The same situation can arise with something like this:
6523 template <class T> class C {
6527 when `C<int>' is instantiated. Now, `f(int)' is defined
6530 if (!new_friend_is_defn)
6531 /* On the other hand, if the in-class declaration does
6532 *not* provide a definition, then we don't want to alter
6533 existing definitions. We can just leave everything
6538 /* Overwrite whatever template info was there before, if
6539 any, with the new template information pertaining to
6541 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
6543 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
6544 reregister_specialization (new_friend,
6545 most_general_template (old_decl),
6550 tree new_friend_args;
6552 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
6553 = new_friend_result_template_info;
6555 new_friend_args = TI_ARGS (new_friend_template_info);
6556 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
6560 tree spec = TREE_VALUE (t);
6563 = add_outermost_template_args (new_friend_args,
6564 DECL_TI_ARGS (spec));
6567 /* Now, since specializations are always supposed to
6568 hang off of the most general template, we must move
6570 t = most_general_template (old_decl);
6573 DECL_TEMPLATE_SPECIALIZATIONS (t)
6574 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
6575 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
6576 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
6581 /* The information from NEW_FRIEND has been merged into OLD_DECL
6582 by duplicate_decls. */
6583 new_friend = old_decl;
6588 tree context = DECL_CONTEXT (new_friend);
6592 template <class T> class C {
6593 template <class U> friend void C1<U>::f (); // case 1
6594 friend void C2<T>::f (); // case 2
6596 we only need to make sure CONTEXT is a complete type for
6597 case 2. To distinguish between the two cases, we note that
6598 CONTEXT of case 1 remains dependent type after tsubst while
6599 this isn't true for case 2. */
6600 ++processing_template_decl;
6601 dependent_p = dependent_type_p (context);
6602 --processing_template_decl;
6605 && !complete_type_or_else (context, NULL_TREE))
6606 return error_mark_node;
6608 if (COMPLETE_TYPE_P (context))
6610 /* Check to see that the declaration is really present, and,
6611 possibly obtain an improved declaration. */
6612 tree fn = check_classfn (context,
6613 new_friend, NULL_TREE);
6623 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
6624 template arguments, as for tsubst.
6626 Returns an appropriate tsubst'd friend type or error_mark_node on
6630 tsubst_friend_class (tree friend_tmpl, tree args)
6636 context = DECL_CONTEXT (friend_tmpl);
6640 if (TREE_CODE (context) == NAMESPACE_DECL)
6641 push_nested_namespace (context);
6643 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
6646 /* Look for a class template declaration. We look for hidden names
6647 because two friend declarations of the same template are the
6648 same. For example, in:
6651 template <typename> friend class F;
6653 template <typename> struct B {
6654 template <typename> friend class F;
6657 both F templates are the same. */
6658 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
6659 /*block_p=*/true, 0,
6660 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
6662 /* But, if we don't find one, it might be because we're in a
6663 situation like this:
6671 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
6672 for `S<int>', not the TEMPLATE_DECL. */
6673 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
6675 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
6676 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
6679 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
6681 /* The friend template has already been declared. Just
6682 check to see that the declarations match, and install any new
6683 default parameters. We must tsubst the default parameters,
6684 of course. We only need the innermost template parameters
6685 because that is all that redeclare_class_template will look
6687 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
6688 > TMPL_ARGS_DEPTH (args))
6691 location_t saved_input_location;
6692 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
6693 args, tf_warning_or_error);
6695 saved_input_location = input_location;
6696 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
6697 redeclare_class_template (TREE_TYPE (tmpl), parms);
6698 input_location = saved_input_location;
6702 friend_type = TREE_TYPE (tmpl);
6706 /* The friend template has not already been declared. In this
6707 case, the instantiation of the template class will cause the
6708 injection of this template into the global scope. */
6709 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
6710 if (tmpl == error_mark_node)
6711 return error_mark_node;
6713 /* The new TMPL is not an instantiation of anything, so we
6714 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
6715 the new type because that is supposed to be the corresponding
6716 template decl, i.e., TMPL. */
6717 DECL_USE_TEMPLATE (tmpl) = 0;
6718 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
6719 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
6720 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
6721 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
6723 /* Inject this template into the global scope. */
6724 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
6729 if (TREE_CODE (context) == NAMESPACE_DECL)
6730 pop_nested_namespace (context);
6732 pop_nested_class ();
6738 /* Returns zero if TYPE cannot be completed later due to circularity.
6739 Otherwise returns one. */
6742 can_complete_type_without_circularity (tree type)
6744 if (type == NULL_TREE || type == error_mark_node)
6746 else if (COMPLETE_TYPE_P (type))
6748 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
6749 return can_complete_type_without_circularity (TREE_TYPE (type));
6750 else if (CLASS_TYPE_P (type)
6751 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
6757 /* Apply any attributes which had to be deferred until instantiation
6758 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
6759 ARGS, COMPLAIN, IN_DECL are as tsubst. */
6762 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
6763 tree args, tsubst_flags_t complain, tree in_decl)
6765 tree last_dep = NULL_TREE;
6769 for (t = attributes; t; t = TREE_CHAIN (t))
6770 if (ATTR_IS_DEPENDENT (t))
6773 attributes = copy_list (attributes);
6777 if (DECL_P (*decl_p))
6779 if (TREE_TYPE (*decl_p) == error_mark_node)
6781 p = &DECL_ATTRIBUTES (*decl_p);
6784 p = &TYPE_ATTRIBUTES (*decl_p);
6788 tree late_attrs = NULL_TREE;
6789 tree *q = &late_attrs;
6791 for (*p = attributes; *p; )
6794 if (ATTR_IS_DEPENDENT (t))
6796 *p = TREE_CHAIN (t);
6797 TREE_CHAIN (t) = NULL_TREE;
6798 /* If the first attribute argument is an identifier, don't
6799 pass it through tsubst. Attributes like mode, format,
6800 cleanup and several target specific attributes expect it
6803 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
6804 && TREE_VALUE (TREE_VALUE (t))
6805 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
6806 == IDENTIFIER_NODE))
6809 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
6811 /*integral_constant_expression_p=*/false);
6812 if (chain != TREE_CHAIN (TREE_VALUE (t)))
6814 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
6819 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
6820 /*integral_constant_expression_p=*/false);
6822 q = &TREE_CHAIN (t);
6825 p = &TREE_CHAIN (t);
6828 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
6833 instantiate_class_template (tree type)
6835 tree templ, args, pattern, t, member;
6840 if (type == error_mark_node)
6841 return error_mark_node;
6843 if (TYPE_BEING_DEFINED (type)
6844 || COMPLETE_TYPE_P (type)
6845 || dependent_type_p (type))
6848 /* Figure out which template is being instantiated. */
6849 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
6850 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
6852 /* Determine what specialization of the original template to
6854 t = most_specialized_class (type, templ);
6855 if (t == error_mark_node)
6857 TYPE_BEING_DEFINED (type) = 1;
6858 return error_mark_node;
6862 /* This TYPE is actually an instantiation of a partial
6863 specialization. We replace the innermost set of ARGS with
6864 the arguments appropriate for substitution. For example,
6867 template <class T> struct S {};
6868 template <class T> struct S<T*> {};
6870 and supposing that we are instantiating S<int*>, ARGS will
6871 presently be {int*} -- but we need {int}. */
6872 pattern = TREE_TYPE (t);
6873 args = TREE_PURPOSE (t);
6877 pattern = TREE_TYPE (templ);
6878 args = CLASSTYPE_TI_ARGS (type);
6881 /* If the template we're instantiating is incomplete, then clearly
6882 there's nothing we can do. */
6883 if (!COMPLETE_TYPE_P (pattern))
6886 /* If we've recursively instantiated too many templates, stop. */
6887 if (! push_tinst_level (type))
6890 /* Now we're really doing the instantiation. Mark the type as in
6891 the process of being defined. */
6892 TYPE_BEING_DEFINED (type) = 1;
6894 /* We may be in the middle of deferred access check. Disable
6896 push_deferring_access_checks (dk_no_deferred);
6898 push_to_top_level ();
6900 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
6902 /* Set the input location to the template definition. This is needed
6903 if tsubsting causes an error. */
6904 typedecl = TYPE_MAIN_DECL (type);
6905 input_location = DECL_SOURCE_LOCATION (typedecl);
6907 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
6908 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
6909 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
6910 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
6911 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
6912 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
6913 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
6914 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
6915 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
6916 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
6917 TYPE_PACKED (type) = TYPE_PACKED (pattern);
6918 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
6919 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
6920 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
6921 if (ANON_AGGR_TYPE_P (pattern))
6922 SET_ANON_AGGR_TYPE_P (type);
6923 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
6925 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
6926 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
6929 pbinfo = TYPE_BINFO (pattern);
6931 /* We should never instantiate a nested class before its enclosing
6932 class; we need to look up the nested class by name before we can
6933 instantiate it, and that lookup should instantiate the enclosing
6935 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
6936 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
6937 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
6939 base_list = NULL_TREE;
6940 if (BINFO_N_BASE_BINFOS (pbinfo))
6943 tree context = TYPE_CONTEXT (type);
6947 /* We must enter the scope containing the type, as that is where
6948 the accessibility of types named in dependent bases are
6950 pushed_scope = push_scope (context ? context : global_namespace);
6952 /* Substitute into each of the bases to determine the actual
6954 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
6957 tree access = BINFO_BASE_ACCESS (pbinfo, i);
6958 tree expanded_bases = NULL_TREE;
6961 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
6964 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
6965 args, tf_error, NULL_TREE);
6966 if (expanded_bases == error_mark_node)
6969 len = TREE_VEC_LENGTH (expanded_bases);
6972 for (idx = 0; idx < len; idx++)
6975 /* Extract the already-expanded base class. */
6976 base = TREE_VEC_ELT (expanded_bases, idx);
6978 /* Substitute to figure out the base class. */
6979 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
6982 if (base == error_mark_node)
6985 base_list = tree_cons (access, base, base_list);
6986 if (BINFO_VIRTUAL_P (pbase_binfo))
6987 TREE_TYPE (base_list) = integer_type_node;
6991 /* The list is now in reverse order; correct that. */
6992 base_list = nreverse (base_list);
6995 pop_scope (pushed_scope);
6997 /* Now call xref_basetypes to set up all the base-class
6999 xref_basetypes (type, base_list);
7001 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
7002 (int) ATTR_FLAG_TYPE_IN_PLACE,
7003 args, tf_error, NULL_TREE);
7005 /* Now that our base classes are set up, enter the scope of the
7006 class, so that name lookups into base classes, etc. will work
7007 correctly. This is precisely analogous to what we do in
7008 begin_class_definition when defining an ordinary non-template
7009 class, except we also need to push the enclosing classes. */
7010 push_nested_class (type);
7012 /* Now members are processed in the order of declaration. */
7013 for (member = CLASSTYPE_DECL_LIST (pattern);
7014 member; member = TREE_CHAIN (member))
7016 tree t = TREE_VALUE (member);
7018 if (TREE_PURPOSE (member))
7022 /* Build new CLASSTYPE_NESTED_UTDS. */
7025 bool class_template_p;
7027 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
7028 && TYPE_LANG_SPECIFIC (t)
7029 && CLASSTYPE_IS_TEMPLATE (t));
7030 /* If the member is a class template, then -- even after
7031 substitution -- there may be dependent types in the
7032 template argument list for the class. We increment
7033 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
7034 that function will assume that no types are dependent
7035 when outside of a template. */
7036 if (class_template_p)
7037 ++processing_template_decl;
7038 newtag = tsubst (t, args, tf_error, NULL_TREE);
7039 if (class_template_p)
7040 --processing_template_decl;
7041 if (newtag == error_mark_node)
7044 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
7046 tree name = TYPE_IDENTIFIER (t);
7048 if (class_template_p)
7049 /* Unfortunately, lookup_template_class sets
7050 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
7051 instantiation (i.e., for the type of a member
7052 template class nested within a template class.)
7053 This behavior is required for
7054 maybe_process_partial_specialization to work
7055 correctly, but is not accurate in this case;
7056 the TAG is not an instantiation of anything.
7057 (The corresponding TEMPLATE_DECL is an
7058 instantiation, but the TYPE is not.) */
7059 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
7061 /* Now, we call pushtag to put this NEWTAG into the scope of
7062 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
7063 pushtag calling push_template_decl. We don't have to do
7064 this for enums because it will already have been done in
7067 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
7068 pushtag (name, newtag, /*tag_scope=*/ts_current);
7071 else if (TREE_CODE (t) == FUNCTION_DECL
7072 || DECL_FUNCTION_TEMPLATE_P (t))
7074 /* Build new TYPE_METHODS. */
7077 if (TREE_CODE (t) == TEMPLATE_DECL)
7078 ++processing_template_decl;
7079 r = tsubst (t, args, tf_error, NULL_TREE);
7080 if (TREE_CODE (t) == TEMPLATE_DECL)
7081 --processing_template_decl;
7082 set_current_access_from_decl (r);
7083 finish_member_declaration (r);
7087 /* Build new TYPE_FIELDS. */
7088 if (TREE_CODE (t) == STATIC_ASSERT)
7091 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
7092 tf_warning_or_error, NULL_TREE,
7093 /*integral_constant_expression_p=*/true);
7094 finish_static_assert (condition,
7095 STATIC_ASSERT_MESSAGE (t),
7096 STATIC_ASSERT_SOURCE_LOCATION (t),
7099 else if (TREE_CODE (t) != CONST_DECL)
7103 /* The file and line for this declaration, to
7104 assist in error message reporting. Since we
7105 called push_tinst_level above, we don't need to
7107 input_location = DECL_SOURCE_LOCATION (t);
7109 if (TREE_CODE (t) == TEMPLATE_DECL)
7110 ++processing_template_decl;
7111 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
7112 if (TREE_CODE (t) == TEMPLATE_DECL)
7113 --processing_template_decl;
7114 if (TREE_CODE (r) == VAR_DECL)
7118 [t]he initialization (and any associated
7119 side-effects) of a static data member does
7120 not occur unless the static data member is
7121 itself used in a way that requires the
7122 definition of the static data member to
7125 Therefore, we do not substitute into the
7126 initialized for the static data member here. */
7127 finish_static_data_member_decl
7130 /*init_const_expr_p=*/false,
7131 /*asmspec_tree=*/NULL_TREE,
7133 if (DECL_INITIALIZED_IN_CLASS_P (r))
7134 check_static_variable_definition (r, TREE_TYPE (r));
7136 else if (TREE_CODE (r) == FIELD_DECL)
7138 /* Determine whether R has a valid type and can be
7139 completed later. If R is invalid, then it is
7140 replaced by error_mark_node so that it will not be
7141 added to TYPE_FIELDS. */
7142 tree rtype = TREE_TYPE (r);
7143 if (can_complete_type_without_circularity (rtype))
7144 complete_type (rtype);
7146 if (!COMPLETE_TYPE_P (rtype))
7148 cxx_incomplete_type_error (r, rtype);
7149 r = error_mark_node;
7153 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
7154 such a thing will already have been added to the field
7155 list by tsubst_enum in finish_member_declaration in the
7156 CLASSTYPE_NESTED_UTDS case above. */
7157 if (!(TREE_CODE (r) == TYPE_DECL
7158 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
7159 && DECL_ARTIFICIAL (r)))
7161 set_current_access_from_decl (r);
7162 finish_member_declaration (r);
7169 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
7171 /* Build new CLASSTYPE_FRIEND_CLASSES. */
7173 tree friend_type = t;
7174 bool adjust_processing_template_decl = false;
7176 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7178 /* template <class T> friend class C; */
7179 friend_type = tsubst_friend_class (friend_type, args);
7180 adjust_processing_template_decl = true;
7182 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
7184 /* template <class T> friend class C::D; */
7185 friend_type = tsubst (friend_type, args,
7186 tf_warning_or_error, NULL_TREE);
7187 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7188 friend_type = TREE_TYPE (friend_type);
7189 adjust_processing_template_decl = true;
7191 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
7193 /* This could be either
7197 when dependent_type_p is false or
7199 template <class U> friend class T::C;
7202 friend_type = tsubst (friend_type, args,
7203 tf_warning_or_error, NULL_TREE);
7204 /* Bump processing_template_decl for correct
7205 dependent_type_p calculation. */
7206 ++processing_template_decl;
7207 if (dependent_type_p (friend_type))
7208 adjust_processing_template_decl = true;
7209 --processing_template_decl;
7211 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
7212 && hidden_name_p (TYPE_NAME (friend_type)))
7216 where C hasn't been declared yet. Let's lookup name
7217 from namespace scope directly, bypassing any name that
7218 come from dependent base class. */
7219 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
7221 /* The call to xref_tag_from_type does injection for friend
7223 push_nested_namespace (ns);
7225 xref_tag_from_type (friend_type, NULL_TREE,
7226 /*tag_scope=*/ts_current);
7227 pop_nested_namespace (ns);
7229 else if (uses_template_parms (friend_type))
7230 /* friend class C<T>; */
7231 friend_type = tsubst (friend_type, args,
7232 tf_warning_or_error, NULL_TREE);
7237 where C is already declared or
7239 friend class C<int>;
7241 We don't have to do anything in these cases. */
7243 if (adjust_processing_template_decl)
7244 /* Trick make_friend_class into realizing that the friend
7245 we're adding is a template, not an ordinary class. It's
7246 important that we use make_friend_class since it will
7247 perform some error-checking and output cross-reference
7249 ++processing_template_decl;
7251 if (friend_type != error_mark_node)
7252 make_friend_class (type, friend_type, /*complain=*/false);
7254 if (adjust_processing_template_decl)
7255 --processing_template_decl;
7259 /* Build new DECL_FRIENDLIST. */
7262 /* The file and line for this declaration, to
7263 assist in error message reporting. Since we
7264 called push_tinst_level above, we don't need to
7266 input_location = DECL_SOURCE_LOCATION (t);
7268 if (TREE_CODE (t) == TEMPLATE_DECL)
7270 ++processing_template_decl;
7271 push_deferring_access_checks (dk_no_check);
7274 r = tsubst_friend_function (t, args);
7275 add_friend (type, r, /*complain=*/false);
7276 if (TREE_CODE (t) == TEMPLATE_DECL)
7278 pop_deferring_access_checks ();
7279 --processing_template_decl;
7285 /* Set the file and line number information to whatever is given for
7286 the class itself. This puts error messages involving generated
7287 implicit functions at a predictable point, and the same point
7288 that would be used for non-template classes. */
7289 input_location = DECL_SOURCE_LOCATION (typedecl);
7291 unreverse_member_declarations (type);
7292 finish_struct_1 (type);
7293 TYPE_BEING_DEFINED (type) = 0;
7295 /* Now that the class is complete, instantiate default arguments for
7296 any member functions. We don't do this earlier because the
7297 default arguments may reference members of the class. */
7298 if (!PRIMARY_TEMPLATE_P (templ))
7299 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
7300 if (TREE_CODE (t) == FUNCTION_DECL
7301 /* Implicitly generated member functions will not have template
7302 information; they are not instantiations, but instead are
7303 created "fresh" for each instantiation. */
7304 && DECL_TEMPLATE_INFO (t))
7305 tsubst_default_arguments (t);
7307 pop_nested_class ();
7308 pop_from_top_level ();
7309 pop_deferring_access_checks ();
7312 /* The vtable for a template class can be emitted in any translation
7313 unit in which the class is instantiated. When there is no key
7314 method, however, finish_struct_1 will already have added TYPE to
7315 the keyed_classes list. */
7316 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
7317 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
7323 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7329 else if (TYPE_P (t))
7330 r = tsubst (t, args, complain, in_decl);
7333 r = tsubst_expr (t, args, complain, in_decl,
7334 /*integral_constant_expression_p=*/true);
7335 r = fold_non_dependent_expr (r);
7340 /* Substitute ARGS into T, which is an pack expansion
7341 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
7342 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
7343 (if only a partial substitution could be performed) or
7344 ERROR_MARK_NODE if there was an error. */
7346 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
7350 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
7351 tree first_arg_pack; int i, len = -1;
7355 gcc_assert (PACK_EXPANSION_P (t));
7356 pattern = PACK_EXPANSION_PATTERN (t);
7358 /* Determine the argument packs that will instantiate the parameter
7359 packs used in the expansion expression. While we're at it,
7360 compute the number of arguments to be expanded and make sure it
7362 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
7363 pack = TREE_CHAIN (pack))
7365 tree parm_pack = TREE_VALUE (pack);
7366 tree arg_pack = NULL_TREE;
7367 tree orig_arg = NULL_TREE;
7369 if (TREE_CODE (parm_pack) == PARM_DECL)
7370 arg_pack = retrieve_local_specialization (parm_pack);
7373 int level, idx, levels;
7374 template_parm_level_and_index (parm_pack, &level, &idx);
7376 levels = TMPL_ARGS_DEPTH (args);
7377 if (level <= levels)
7378 arg_pack = TMPL_ARG (args, level, idx);
7381 orig_arg = arg_pack;
7382 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
7383 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
7385 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
7386 /* This can only happen if we forget to expand an argument
7387 pack somewhere else. Just return an error, silently. */
7389 result = make_tree_vec (1);
7390 TREE_VEC_ELT (result, 0) = error_mark_node;
7395 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
7396 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
7398 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
7399 tree pattern = PACK_EXPANSION_PATTERN (expansion);
7400 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
7401 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
7402 /* The argument pack that the parameter maps to is just an
7403 expansion of the parameter itself, such as one would
7404 find in the implicit typedef of a class inside the
7405 class itself. Consider this parameter "unsubstituted",
7406 so that we will maintain the outer pack expansion. */
7407 arg_pack = NULL_TREE;
7413 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
7415 /* It's all-or-nothing with incomplete argument packs. */
7416 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7417 return error_mark_node;
7419 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7425 first_arg_pack = arg_pack;
7427 else if (len != my_len)
7429 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
7430 error ("mismatched argument pack lengths while expanding "
7434 error ("mismatched argument pack lengths while expanding "
7437 return error_mark_node;
7440 /* Keep track of the parameter packs and their corresponding
7442 packs = tree_cons (parm_pack, arg_pack, packs);
7443 TREE_TYPE (packs) = orig_arg;
7446 /* We can't substitute for this parameter pack. */
7447 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
7449 unsubstituted_packs);
7452 /* We cannot expand this expansion expression, because we don't have
7453 all of the argument packs we need. Substitute into the pattern
7454 and return a PACK_EXPANSION_*. The caller will need to deal with
7456 if (unsubstituted_packs)
7457 return make_pack_expansion (tsubst (pattern, args, complain,
7460 /* We could not find any argument packs that work. */
7462 return error_mark_node;
7464 /* For each argument in each argument pack, substitute into the
7466 result = make_tree_vec (len + incomplete);
7467 for (i = 0; i < len + incomplete; ++i)
7469 /* For parameter pack, change the substitution of the parameter
7470 pack to the ith argument in its argument pack, then expand
7472 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7474 tree parm = TREE_PURPOSE (pack);
7476 if (TREE_CODE (parm) == PARM_DECL)
7478 /* Select the Ith argument from the pack. */
7479 tree arg = make_node (ARGUMENT_PACK_SELECT);
7480 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
7481 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
7483 register_local_specialization (arg, parm);
7489 template_parm_level_and_index (parm, &level, &idx);
7493 /* Select the Ith argument from the pack. */
7494 value = make_node (ARGUMENT_PACK_SELECT);
7495 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
7496 ARGUMENT_PACK_SELECT_INDEX (value) = i;
7499 /* Update the corresponding argument. */
7500 TMPL_ARG (args, level, idx) = value;
7504 /* Substitute into the PATTERN with the altered arguments. */
7505 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
7506 TREE_VEC_ELT (result, i) =
7507 tsubst_expr (pattern, args, complain, in_decl,
7508 /*integral_constant_expression_p=*/false);
7510 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
7513 /* When we have incomplete argument packs, the last "expanded"
7514 result is itself a pack expansion, which allows us
7515 to deduce more arguments. */
7516 TREE_VEC_ELT (result, i) =
7517 make_pack_expansion (TREE_VEC_ELT (result, i));
7519 if (TREE_VEC_ELT (result, i) == error_mark_node)
7521 result = error_mark_node;
7526 /* Update ARGS to restore the substitution from parameter packs to
7527 their argument packs. */
7528 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7530 tree parm = TREE_PURPOSE (pack);
7532 if (TREE_CODE (parm) == PARM_DECL)
7533 register_local_specialization (TREE_TYPE (pack), parm);
7537 template_parm_level_and_index (parm, &level, &idx);
7539 /* Update the corresponding argument. */
7540 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
7541 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
7544 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
7551 /* Substitute ARGS into the vector or list of template arguments T. */
7554 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7557 int len = TREE_VEC_LENGTH (t);
7558 int need_new = 0, i, expanded_len_adjust = 0, out;
7559 tree *elts = (tree *) alloca (len * sizeof (tree));
7561 for (i = 0; i < len; i++)
7563 tree orig_arg = TREE_VEC_ELT (t, i);
7566 if (TREE_CODE (orig_arg) == TREE_VEC)
7567 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
7568 else if (PACK_EXPANSION_P (orig_arg))
7570 /* Substitute into an expansion expression. */
7571 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
7573 if (TREE_CODE (new_arg) == TREE_VEC)
7574 /* Add to the expanded length adjustment the number of
7575 expanded arguments. We subtract one from this
7576 measurement, because the argument pack expression
7577 itself is already counted as 1 in
7578 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
7579 the argument pack is empty. */
7580 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
7582 else if (ARGUMENT_PACK_P (orig_arg))
7584 /* Substitute into each of the arguments. */
7585 new_arg = make_node (TREE_CODE (orig_arg));
7587 SET_ARGUMENT_PACK_ARGS (
7589 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
7590 args, complain, in_decl));
7592 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
7593 new_arg = error_mark_node;
7595 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
7596 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
7598 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
7600 if (TREE_TYPE (new_arg) == error_mark_node)
7601 new_arg = error_mark_node;
7605 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
7607 if (new_arg == error_mark_node)
7608 return error_mark_node;
7611 if (new_arg != orig_arg)
7618 /* Make space for the expanded arguments coming from template
7620 t = make_tree_vec (len + expanded_len_adjust);
7621 for (i = 0, out = 0; i < len; i++)
7623 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
7624 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
7625 && TREE_CODE (elts[i]) == TREE_VEC)
7629 /* Now expand the template argument pack "in place". */
7630 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
7631 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
7635 TREE_VEC_ELT (t, out) = elts[i];
7643 /* Return the result of substituting ARGS into the template parameters
7644 given by PARMS. If there are m levels of ARGS and m + n levels of
7645 PARMS, then the result will contain n levels of PARMS. For
7646 example, if PARMS is `template <class T> template <class U>
7647 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
7648 result will be `template <int*, double, class V>'. */
7651 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
7656 /* When substituting into a template, we must set
7657 PROCESSING_TEMPLATE_DECL as the template parameters may be
7658 dependent if they are based on one-another, and the dependency
7659 predicates are short-circuit outside of templates. */
7660 ++processing_template_decl;
7662 for (new_parms = &r;
7663 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
7664 new_parms = &(TREE_CHAIN (*new_parms)),
7665 parms = TREE_CHAIN (parms))
7668 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
7671 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
7677 if (parms == error_mark_node)
7680 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
7682 if (tuple == error_mark_node)
7685 default_value = TREE_PURPOSE (tuple);
7686 parm_decl = TREE_VALUE (tuple);
7688 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
7689 if (TREE_CODE (parm_decl) == PARM_DECL
7690 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
7691 parm_decl = error_mark_node;
7692 default_value = tsubst_template_arg (default_value, args,
7693 complain, NULL_TREE);
7695 tuple = build_tree_list (default_value, parm_decl);
7696 TREE_VEC_ELT (new_vec, i) = tuple;
7700 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
7701 - TMPL_ARGS_DEPTH (args)),
7702 new_vec, NULL_TREE);
7705 --processing_template_decl;
7710 /* Substitute the ARGS into the indicated aggregate (or enumeration)
7711 type T. If T is not an aggregate or enumeration type, it is
7712 handled as if by tsubst. IN_DECL is as for tsubst. If
7713 ENTERING_SCOPE is nonzero, T is the context for a template which
7714 we are presently tsubst'ing. Return the substituted value. */
7717 tsubst_aggr_type (tree t,
7719 tsubst_flags_t complain,
7726 switch (TREE_CODE (t))
7729 if (TYPE_PTRMEMFUNC_P (t))
7730 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
7732 /* Else fall through. */
7735 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
7740 bool saved_skip_evaluation;
7742 /* In "sizeof(X<I>)" we need to evaluate "I". */
7743 saved_skip_evaluation = skip_evaluation;
7744 skip_evaluation = false;
7746 /* First, determine the context for the type we are looking
7748 context = TYPE_CONTEXT (t);
7751 context = tsubst_aggr_type (context, args, complain,
7752 in_decl, /*entering_scope=*/1);
7753 /* If context is a nested class inside a class template,
7754 it may still need to be instantiated (c++/33959). */
7755 if (TYPE_P (context))
7756 context = complete_type (context);
7759 /* Then, figure out what arguments are appropriate for the
7760 type we are trying to find. For example, given:
7762 template <class T> struct S;
7763 template <class T, class U> void f(T, U) { S<U> su; }
7765 and supposing that we are instantiating f<int, double>,
7766 then our ARGS will be {int, double}, but, when looking up
7767 S we only want {double}. */
7768 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
7770 if (argvec == error_mark_node)
7771 r = error_mark_node;
7774 r = lookup_template_class (t, argvec, in_decl, context,
7775 entering_scope, complain);
7776 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7779 skip_evaluation = saved_skip_evaluation;
7784 /* This is not a template type, so there's nothing to do. */
7788 return tsubst (t, args, complain, in_decl);
7792 /* Substitute into the default argument ARG (a default argument for
7793 FN), which has the indicated TYPE. */
7796 tsubst_default_argument (tree fn, tree type, tree arg)
7798 tree saved_class_ptr = NULL_TREE;
7799 tree saved_class_ref = NULL_TREE;
7801 /* This default argument came from a template. Instantiate the
7802 default argument here, not in tsubst. In the case of
7811 we must be careful to do name lookup in the scope of S<T>,
7812 rather than in the current class. */
7813 push_access_scope (fn);
7814 /* The "this" pointer is not valid in a default argument. */
7817 saved_class_ptr = current_class_ptr;
7818 cp_function_chain->x_current_class_ptr = NULL_TREE;
7819 saved_class_ref = current_class_ref;
7820 cp_function_chain->x_current_class_ref = NULL_TREE;
7823 push_deferring_access_checks(dk_no_deferred);
7824 /* The default argument expression may cause implicitly defined
7825 member functions to be synthesized, which will result in garbage
7826 collection. We must treat this situation as if we were within
7827 the body of function so as to avoid collecting live data on the
7830 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
7831 tf_warning_or_error, NULL_TREE,
7832 /*integral_constant_expression_p=*/false);
7834 pop_deferring_access_checks();
7836 /* Restore the "this" pointer. */
7839 cp_function_chain->x_current_class_ptr = saved_class_ptr;
7840 cp_function_chain->x_current_class_ref = saved_class_ref;
7843 pop_access_scope (fn);
7845 /* Make sure the default argument is reasonable. */
7846 arg = check_default_argument (type, arg);
7851 /* Substitute into all the default arguments for FN. */
7854 tsubst_default_arguments (tree fn)
7859 tmpl_args = DECL_TI_ARGS (fn);
7861 /* If this function is not yet instantiated, we certainly don't need
7862 its default arguments. */
7863 if (uses_template_parms (tmpl_args))
7866 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
7868 arg = TREE_CHAIN (arg))
7869 if (TREE_PURPOSE (arg))
7870 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
7872 TREE_PURPOSE (arg));
7875 /* Substitute the ARGS into the T, which is a _DECL. Return the
7876 result of the substitution. Issue error and warning messages under
7877 control of COMPLAIN. */
7880 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
7882 location_t saved_loc;
7886 /* Set the filename and linenumber to improve error-reporting. */
7887 saved_loc = input_location;
7888 input_location = DECL_SOURCE_LOCATION (t);
7890 switch (TREE_CODE (t))
7894 /* We can get here when processing a member function template,
7895 member class template, and template template parameter of
7896 a template class. */
7897 tree decl = DECL_TEMPLATE_RESULT (t);
7902 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7904 /* Template template parameter is treated here. */
7905 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7906 if (new_type == error_mark_node)
7907 return error_mark_node;
7910 TREE_CHAIN (r) = NULL_TREE;
7911 TREE_TYPE (r) = new_type;
7912 DECL_TEMPLATE_RESULT (r)
7913 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
7914 DECL_TEMPLATE_PARMS (r)
7915 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
7917 TYPE_NAME (new_type) = r;
7921 /* We might already have an instance of this template.
7922 The ARGS are for the surrounding class type, so the
7923 full args contain the tsubst'd args for the context,
7924 plus the innermost args from the template decl. */
7925 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
7926 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
7927 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
7928 /* Because this is a template, the arguments will still be
7929 dependent, even after substitution. If
7930 PROCESSING_TEMPLATE_DECL is not set, the dependency
7931 predicates will short-circuit. */
7932 ++processing_template_decl;
7933 full_args = tsubst_template_args (tmpl_args, args,
7935 --processing_template_decl;
7936 if (full_args == error_mark_node)
7937 return error_mark_node;
7939 /* tsubst_template_args doesn't copy the vector if
7940 nothing changed. But, *something* should have
7942 gcc_assert (full_args != tmpl_args);
7944 spec = retrieve_specialization (t, full_args,
7945 /*class_specializations_p=*/true);
7946 if (spec != NULL_TREE)
7952 /* Make a new template decl. It will be similar to the
7953 original, but will record the current template arguments.
7954 We also create a new function declaration, which is just
7955 like the old one, but points to this new template, rather
7956 than the old one. */
7958 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
7959 TREE_CHAIN (r) = NULL_TREE;
7961 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
7963 if (TREE_CODE (decl) == TYPE_DECL)
7966 ++processing_template_decl;
7967 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7968 --processing_template_decl;
7969 if (new_type == error_mark_node)
7970 return error_mark_node;
7972 TREE_TYPE (r) = new_type;
7973 CLASSTYPE_TI_TEMPLATE (new_type) = r;
7974 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
7975 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
7976 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
7981 ++processing_template_decl;
7982 new_decl = tsubst (decl, args, complain, in_decl);
7983 --processing_template_decl;
7984 if (new_decl == error_mark_node)
7985 return error_mark_node;
7987 DECL_TEMPLATE_RESULT (r) = new_decl;
7988 DECL_TI_TEMPLATE (new_decl) = r;
7989 TREE_TYPE (r) = TREE_TYPE (new_decl);
7990 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
7991 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
7994 SET_DECL_IMPLICIT_INSTANTIATION (r);
7995 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
7996 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
7998 /* The template parameters for this new template are all the
7999 template parameters for the old template, except the
8000 outermost level of parameters. */
8001 DECL_TEMPLATE_PARMS (r)
8002 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8005 if (PRIMARY_TEMPLATE_P (t))
8006 DECL_PRIMARY_TEMPLATE (r) = r;
8008 if (TREE_CODE (decl) != TYPE_DECL)
8009 /* Record this non-type partial instantiation. */
8010 register_specialization (r, t,
8011 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
8019 tree argvec = NULL_TREE;
8027 /* Nobody should be tsubst'ing into non-template functions. */
8028 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
8030 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
8035 /* If T is not dependent, just return it. We have to
8036 increment PROCESSING_TEMPLATE_DECL because
8037 value_dependent_expression_p assumes that nothing is
8038 dependent when PROCESSING_TEMPLATE_DECL is zero. */
8039 ++processing_template_decl;
8040 dependent_p = value_dependent_expression_p (t);
8041 --processing_template_decl;
8045 /* Calculate the most general template of which R is a
8046 specialization, and the complete set of arguments used to
8048 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
8049 argvec = tsubst_template_args (DECL_TI_ARGS
8050 (DECL_TEMPLATE_RESULT (gen_tmpl)),
8051 args, complain, in_decl);
8053 /* Check to see if we already have this specialization. */
8054 spec = retrieve_specialization (gen_tmpl, argvec,
8055 /*class_specializations_p=*/false);
8063 /* We can see more levels of arguments than parameters if
8064 there was a specialization of a member template, like
8067 template <class T> struct S { template <class U> void f(); }
8068 template <> template <class U> void S<int>::f(U);
8070 Here, we'll be substituting into the specialization,
8071 because that's where we can find the code we actually
8072 want to generate, but we'll have enough arguments for
8073 the most general template.
8075 We also deal with the peculiar case:
8077 template <class T> struct S {
8078 template <class U> friend void f();
8080 template <class U> void f() {}
8082 template void f<double>();
8084 Here, the ARGS for the instantiation of will be {int,
8085 double}. But, we only need as many ARGS as there are
8086 levels of template parameters in CODE_PATTERN. We are
8087 careful not to get fooled into reducing the ARGS in
8090 template <class T> struct S { template <class U> void f(U); }
8091 template <class T> template <> void S<T>::f(int) {}
8093 which we can spot because the pattern will be a
8094 specialization in this case. */
8095 args_depth = TMPL_ARGS_DEPTH (args);
8097 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
8098 if (args_depth > parms_depth
8099 && !DECL_TEMPLATE_SPECIALIZATION (t))
8100 args = get_innermost_template_args (args, parms_depth);
8104 /* This special case arises when we have something like this:
8106 template <class T> struct S {
8107 friend void f<int>(int, double);
8110 Here, the DECL_TI_TEMPLATE for the friend declaration
8111 will be an IDENTIFIER_NODE. We are being called from
8112 tsubst_friend_function, and we want only to create a
8113 new decl (R) with appropriate types so that we can call
8114 determine_specialization. */
8115 gen_tmpl = NULL_TREE;
8118 if (DECL_CLASS_SCOPE_P (t))
8120 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
8124 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
8125 complain, t, /*entering_scope=*/1);
8130 ctx = DECL_CONTEXT (t);
8132 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8133 if (type == error_mark_node)
8134 return error_mark_node;
8136 /* We do NOT check for matching decls pushed separately at this
8137 point, as they may not represent instantiations of this
8138 template, and in any case are considered separate under the
8141 DECL_USE_TEMPLATE (r) = 0;
8142 TREE_TYPE (r) = type;
8143 /* Clear out the mangled name and RTL for the instantiation. */
8144 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8145 SET_DECL_RTL (r, NULL_RTX);
8146 /* Leave DECL_INITIAL set on deleted instantiations. */
8147 if (!DECL_DELETED_FN (r))
8148 DECL_INITIAL (r) = NULL_TREE;
8149 DECL_CONTEXT (r) = ctx;
8151 if (member && DECL_CONV_FN_P (r))
8152 /* Type-conversion operator. Reconstruct the name, in
8153 case it's the name of one of the template's parameters. */
8154 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
8156 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
8158 DECL_RESULT (r) = NULL_TREE;
8160 TREE_STATIC (r) = 0;
8161 TREE_PUBLIC (r) = TREE_PUBLIC (t);
8162 DECL_EXTERNAL (r) = 1;
8163 /* If this is an instantiation of a function with internal
8164 linkage, we already know what object file linkage will be
8165 assigned to the instantiation. */
8166 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
8167 DECL_DEFER_OUTPUT (r) = 0;
8168 TREE_CHAIN (r) = NULL_TREE;
8169 DECL_PENDING_INLINE_INFO (r) = 0;
8170 DECL_PENDING_INLINE_P (r) = 0;
8171 DECL_SAVED_TREE (r) = NULL_TREE;
8173 if (DECL_CLONED_FUNCTION (r))
8175 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
8177 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
8178 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
8181 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
8182 this in the special friend case mentioned above where
8183 GEN_TMPL is NULL. */
8186 DECL_TEMPLATE_INFO (r)
8187 = tree_cons (gen_tmpl, argvec, NULL_TREE);
8188 SET_DECL_IMPLICIT_INSTANTIATION (r);
8189 register_specialization (r, gen_tmpl, argvec, false);
8191 /* We're not supposed to instantiate default arguments
8192 until they are called, for a template. But, for a
8195 template <class T> void f ()
8196 { extern void g(int i = T()); }
8198 we should do the substitution when the template is
8199 instantiated. We handle the member function case in
8200 instantiate_class_template since the default arguments
8201 might refer to other members of the class. */
8203 && !PRIMARY_TEMPLATE_P (gen_tmpl)
8204 && !uses_template_parms (argvec))
8205 tsubst_default_arguments (r);
8208 DECL_TEMPLATE_INFO (r) = NULL_TREE;
8210 /* Copy the list of befriending classes. */
8211 for (friends = &DECL_BEFRIENDING_CLASSES (r);
8213 friends = &TREE_CHAIN (*friends))
8215 *friends = copy_node (*friends);
8216 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
8221 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
8223 maybe_retrofit_in_chrg (r);
8224 if (DECL_CONSTRUCTOR_P (r))
8225 grok_ctor_properties (ctx, r);
8226 /* If this is an instantiation of a member template, clone it.
8227 If it isn't, that'll be handled by
8228 clone_constructors_and_destructors. */
8229 if (PRIMARY_TEMPLATE_P (gen_tmpl))
8230 clone_function_decl (r, /*update_method_vec_p=*/0);
8232 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r))
8233 && !grok_op_properties (r, (complain & tf_error) != 0))
8234 return error_mark_node;
8236 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
8237 SET_DECL_FRIEND_CONTEXT (r,
8238 tsubst (DECL_FRIEND_CONTEXT (t),
8239 args, complain, in_decl));
8241 /* Possibly limit visibility based on template args. */
8242 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8243 if (DECL_VISIBILITY_SPECIFIED (t))
8245 DECL_VISIBILITY_SPECIFIED (r) = 0;
8247 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8249 determine_visibility (r);
8251 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8252 args, complain, in_decl);
8258 tree type = NULL_TREE;
8260 tree expanded_types = NULL_TREE;
8261 tree prev_r = NULL_TREE;
8262 tree first_r = NULL_TREE;
8264 if (FUNCTION_PARAMETER_PACK_P (t))
8266 /* If there is a local specialization that isn't a
8267 parameter pack, it means that we're doing a "simple"
8268 substitution from inside tsubst_pack_expansion. Just
8269 return the local specialization (which will be a single
8271 tree spec = retrieve_local_specialization (t);
8273 && TREE_CODE (spec) == PARM_DECL
8274 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
8277 /* Expand the TYPE_PACK_EXPANSION that provides the types for
8278 the parameters in this function parameter pack. */
8279 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
8281 if (TREE_CODE (expanded_types) == TREE_VEC)
8283 len = TREE_VEC_LENGTH (expanded_types);
8285 /* Zero-length parameter packs are boring. Just substitute
8288 return tsubst (TREE_CHAIN (t), args, complain,
8293 /* All we did was update the type. Make a note of that. */
8294 type = expanded_types;
8295 expanded_types = NULL_TREE;
8299 /* Loop through all of the parameter's we'll build. When T is
8300 a function parameter pack, LEN is the number of expanded
8301 types in EXPANDED_TYPES; otherwise, LEN is 1. */
8303 for (i = 0; i < len; ++i)
8307 if (DECL_TEMPLATE_PARM_P (t))
8308 SET_DECL_TEMPLATE_PARM_P (r);
8311 /* We're on the Ith parameter of the function parameter
8314 /* Get the Ith type. */
8315 type = TREE_VEC_ELT (expanded_types, i);
8318 /* Rename the parameter to include the index. */
8320 make_ith_pack_parameter_name (DECL_NAME (r), i);
8323 /* We're dealing with a normal parameter. */
8324 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8326 type = type_decays_to (type);
8327 TREE_TYPE (r) = type;
8328 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8330 if (DECL_INITIAL (r))
8332 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
8333 DECL_INITIAL (r) = TREE_TYPE (r);
8335 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
8339 DECL_CONTEXT (r) = NULL_TREE;
8341 if (!DECL_TEMPLATE_PARM_P (r))
8342 DECL_ARG_TYPE (r) = type_passed_as (type);
8344 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8345 args, complain, in_decl);
8347 /* Keep track of the first new parameter we
8348 generate. That's what will be returned to the
8353 /* Build a proper chain of parameters when substituting
8354 into a function parameter pack. */
8356 TREE_CHAIN (prev_r) = r;
8360 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
8361 complain, TREE_CHAIN (t));
8363 /* FIRST_R contains the start of the chain we've built. */
8373 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8374 if (type == error_mark_node)
8375 return error_mark_node;
8376 TREE_TYPE (r) = type;
8377 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8379 /* DECL_INITIAL gives the number of bits in a bit-field. */
8381 = tsubst_expr (DECL_INITIAL (t), args,
8383 /*integral_constant_expression_p=*/true);
8384 /* We don't have to set DECL_CONTEXT here; it is set by
8385 finish_member_declaration. */
8386 TREE_CHAIN (r) = NULL_TREE;
8387 if (VOID_TYPE_P (type))
8388 error ("instantiation of %q+D as type %qT", r, type);
8390 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8391 args, complain, in_decl);
8396 /* We reach here only for member using decls. */
8397 if (DECL_DEPENDENT_P (t))
8399 r = do_class_using_decl
8400 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
8401 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
8403 r = error_mark_node;
8408 TREE_CHAIN (r) = NULL_TREE;
8415 tree argvec = NULL_TREE;
8416 tree gen_tmpl = NULL_TREE;
8418 tree tmpl = NULL_TREE;
8420 tree type = NULL_TREE;
8423 if (TREE_CODE (t) == TYPE_DECL
8424 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
8426 /* If this is the canonical decl, we don't have to
8427 mess with instantiations, and often we can't (for
8428 typename, template type parms and such). Note that
8429 TYPE_NAME is not correct for the above test if
8430 we've copied the type for a typedef. */
8431 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8432 if (type == error_mark_node)
8433 return error_mark_node;
8434 r = TYPE_NAME (type);
8438 /* Check to see if we already have the specialization we
8441 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
8443 /* T is a static data member or namespace-scope entity.
8444 We have to substitute into namespace-scope variables
8445 (even though such entities are never templates) because
8448 template <class T> void f() { extern T t; }
8450 where the entity referenced is not known until
8451 instantiation time. */
8453 ctx = DECL_CONTEXT (t);
8454 if (DECL_CLASS_SCOPE_P (t))
8456 ctx = tsubst_aggr_type (ctx, args,
8458 in_decl, /*entering_scope=*/1);
8459 /* If CTX is unchanged, then T is in fact the
8460 specialization we want. That situation occurs when
8461 referencing a static data member within in its own
8462 class. We can use pointer equality, rather than
8463 same_type_p, because DECL_CONTEXT is always
8465 if (ctx == DECL_CONTEXT (t))
8471 tmpl = DECL_TI_TEMPLATE (t);
8472 gen_tmpl = most_general_template (tmpl);
8473 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
8474 spec = (retrieve_specialization
8476 /*class_specializations_p=*/false));
8481 /* A local variable. */
8483 /* Subsequent calls to pushdecl will fill this in. */
8485 spec = retrieve_local_specialization (t);
8487 /* If we already have the specialization we need, there is
8488 nothing more to do. */
8495 /* Create a new node for the specialization we need. */
8497 if (type == NULL_TREE)
8498 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8499 if (TREE_CODE (r) == VAR_DECL)
8501 /* Even if the original location is out of scope, the
8502 newly substituted one is not. */
8503 DECL_DEAD_FOR_LOCAL (r) = 0;
8504 DECL_INITIALIZED_P (r) = 0;
8505 DECL_TEMPLATE_INSTANTIATED (r) = 0;
8506 if (type == error_mark_node)
8507 return error_mark_node;
8508 if (TREE_CODE (type) == FUNCTION_TYPE)
8510 /* It may seem that this case cannot occur, since:
8515 declares a function, not a variable. However:
8518 template <typename T> void g() { T t; }
8519 template void g<f>();
8521 is an attempt to declare a variable with function
8523 error ("variable %qD has function type",
8524 /* R is not yet sufficiently initialized, so we
8525 just use its name. */
8527 return error_mark_node;
8529 type = complete_type (type);
8530 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
8531 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
8532 type = check_var_type (DECL_NAME (r), type);
8534 if (DECL_HAS_VALUE_EXPR_P (t))
8536 tree ve = DECL_VALUE_EXPR (t);
8537 ve = tsubst_expr (ve, args, complain, in_decl,
8538 /*constant_expression_p=*/false);
8539 SET_DECL_VALUE_EXPR (r, ve);
8542 else if (DECL_SELF_REFERENCE_P (t))
8543 SET_DECL_SELF_REFERENCE_P (r);
8544 TREE_TYPE (r) = type;
8545 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8546 DECL_CONTEXT (r) = ctx;
8547 /* Clear out the mangled name and RTL for the instantiation. */
8548 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8549 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8550 SET_DECL_RTL (r, NULL_RTX);
8551 /* The initializer must not be expanded until it is required;
8553 DECL_INITIAL (r) = NULL_TREE;
8554 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8555 SET_DECL_RTL (r, NULL_RTX);
8556 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
8557 if (TREE_CODE (r) == VAR_DECL)
8559 /* Possibly limit visibility based on template args. */
8560 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8561 if (DECL_VISIBILITY_SPECIFIED (t))
8563 DECL_VISIBILITY_SPECIFIED (r) = 0;
8565 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8567 determine_visibility (r);
8569 /* Preserve a typedef that names a type. */
8570 else if (TREE_CODE (r) == TYPE_DECL
8571 && DECL_ORIGINAL_TYPE (t)
8572 && type != error_mark_node)
8574 DECL_ORIGINAL_TYPE (r) = tsubst (DECL_ORIGINAL_TYPE (t),
8575 args, complain, in_decl);
8576 TREE_TYPE (r) = type = build_variant_type_copy (type);
8577 TYPE_NAME (type) = r;
8582 /* A static data member declaration is always marked
8583 external when it is declared in-class, even if an
8584 initializer is present. We mimic the non-template
8586 DECL_EXTERNAL (r) = 1;
8588 register_specialization (r, gen_tmpl, argvec, false);
8589 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
8590 SET_DECL_IMPLICIT_INSTANTIATION (r);
8593 register_local_specialization (r, t);
8595 TREE_CHAIN (r) = NULL_TREE;
8597 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
8598 (int) ATTR_FLAG_TYPE_IN_PLACE,
8599 args, complain, in_decl);
8608 /* Restore the file and line information. */
8609 input_location = saved_loc;
8614 /* Substitute into the ARG_TYPES of a function type. */
8617 tsubst_arg_types (tree arg_types,
8619 tsubst_flags_t complain,
8622 tree remaining_arg_types;
8623 tree type = NULL_TREE;
8625 tree expanded_args = NULL_TREE;
8628 if (!arg_types || arg_types == void_list_node)
8631 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
8632 args, complain, in_decl);
8633 if (remaining_arg_types == error_mark_node)
8634 return error_mark_node;
8636 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
8638 /* For a pack expansion, perform substitution on the
8639 entire expression. Later on, we'll handle the arguments
8641 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
8642 args, complain, in_decl);
8644 if (TREE_CODE (expanded_args) == TREE_VEC)
8645 /* So that we'll spin through the parameters, one by one. */
8646 i = TREE_VEC_LENGTH (expanded_args);
8649 /* We only partially substituted into the parameter
8650 pack. Our type is TYPE_PACK_EXPANSION. */
8651 type = expanded_args;
8652 expanded_args = NULL_TREE;
8660 type = TREE_VEC_ELT (expanded_args, i);
8662 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
8664 if (type == error_mark_node)
8665 return error_mark_node;
8666 if (VOID_TYPE_P (type))
8668 if (complain & tf_error)
8670 error ("invalid parameter type %qT", type);
8672 error ("in declaration %q+D", in_decl);
8674 return error_mark_node;
8677 /* Do array-to-pointer, function-to-pointer conversion, and ignore
8678 top-level qualifiers as required. */
8679 type = TYPE_MAIN_VARIANT (type_decays_to (type));
8681 /* We do not substitute into default arguments here. The standard
8682 mandates that they be instantiated only when needed, which is
8683 done in build_over_call. */
8684 default_arg = TREE_PURPOSE (arg_types);
8686 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
8688 /* We've instantiated a template before its default arguments
8689 have been parsed. This can happen for a nested template
8690 class, and is not an error unless we require the default
8691 argument in a call of this function. */
8692 remaining_arg_types =
8693 tree_cons (default_arg, type, remaining_arg_types);
8694 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
8695 remaining_arg_types);
8698 remaining_arg_types =
8699 hash_tree_cons (default_arg, type, remaining_arg_types);
8702 return remaining_arg_types;
8705 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
8706 *not* handle the exception-specification for FNTYPE, because the
8707 initial substitution of explicitly provided template parameters
8708 during argument deduction forbids substitution into the
8709 exception-specification:
8713 All references in the function type of the function template to the
8714 corresponding template parameters are replaced by the specified tem-
8715 plate argument values. If a substitution in a template parameter or
8716 in the function type of the function template results in an invalid
8717 type, type deduction fails. [Note: The equivalent substitution in
8718 exception specifications is done only when the function is instanti-
8719 ated, at which point a program is ill-formed if the substitution
8720 results in an invalid type.] */
8723 tsubst_function_type (tree t,
8725 tsubst_flags_t complain,
8732 /* The TYPE_CONTEXT is not used for function/method types. */
8733 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
8735 /* Substitute the return type. */
8736 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8737 if (return_type == error_mark_node)
8738 return error_mark_node;
8739 /* The standard does not presently indicate that creation of a
8740 function type with an invalid return type is a deduction failure.
8741 However, that is clearly analogous to creating an array of "void"
8742 or a reference to a reference. This is core issue #486. */
8743 if (TREE_CODE (return_type) == ARRAY_TYPE
8744 || TREE_CODE (return_type) == FUNCTION_TYPE)
8746 if (complain & tf_error)
8748 if (TREE_CODE (return_type) == ARRAY_TYPE)
8749 error ("function returning an array");
8751 error ("function returning a function");
8753 return error_mark_node;
8756 /* Substitute the argument types. */
8757 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
8759 if (arg_types == error_mark_node)
8760 return error_mark_node;
8762 /* Construct a new type node and return it. */
8763 if (TREE_CODE (t) == FUNCTION_TYPE)
8764 fntype = build_function_type (return_type, arg_types);
8767 tree r = TREE_TYPE (TREE_VALUE (arg_types));
8768 if (! MAYBE_CLASS_TYPE_P (r))
8772 Type deduction may fail for any of the following
8775 -- Attempting to create "pointer to member of T" when T
8776 is not a class type. */
8777 if (complain & tf_error)
8778 error ("creating pointer to member function of non-class type %qT",
8780 return error_mark_node;
8783 fntype = build_method_type_directly (r, return_type,
8784 TREE_CHAIN (arg_types));
8786 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
8787 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
8792 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
8793 ARGS into that specification, and return the substituted
8794 specification. If there is no specification, return NULL_TREE. */
8797 tsubst_exception_specification (tree fntype,
8799 tsubst_flags_t complain,
8805 specs = TYPE_RAISES_EXCEPTIONS (fntype);
8806 new_specs = NULL_TREE;
8809 if (! TREE_VALUE (specs))
8816 tree expanded_specs = NULL_TREE;
8818 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
8820 /* Expand the pack expansion type. */
8821 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
8825 if (expanded_specs == error_mark_node)
8826 return error_mark_node;
8827 else if (TREE_CODE (expanded_specs) == TREE_VEC)
8828 len = TREE_VEC_LENGTH (expanded_specs);
8831 /* We're substituting into a member template, so
8832 we got a TYPE_PACK_EXPANSION back. Add that
8833 expansion and move on. */
8834 gcc_assert (TREE_CODE (expanded_specs)
8835 == TYPE_PACK_EXPANSION);
8836 new_specs = add_exception_specifier (new_specs,
8839 specs = TREE_CHAIN (specs);
8844 for (i = 0; i < len; ++i)
8847 spec = TREE_VEC_ELT (expanded_specs, i);
8849 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
8850 if (spec == error_mark_node)
8852 new_specs = add_exception_specifier (new_specs, spec,
8856 specs = TREE_CHAIN (specs);
8862 /* Take the tree structure T and replace template parameters used
8863 therein with the argument vector ARGS. IN_DECL is an associated
8864 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
8865 Issue error and warning messages under control of COMPLAIN. Note
8866 that we must be relatively non-tolerant of extensions here, in
8867 order to preserve conformance; if we allow substitutions that
8868 should not be allowed, we may allow argument deductions that should
8869 not succeed, and therefore report ambiguous overload situations
8870 where there are none. In theory, we could allow the substitution,
8871 but indicate that it should have failed, and allow our caller to
8872 make sure that the right thing happens, but we don't try to do this
8875 This function is used for dealing with types, decls and the like;
8876 for expressions, use tsubst_expr or tsubst_copy. */
8879 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8883 if (t == NULL_TREE || t == error_mark_node
8884 || t == integer_type_node
8885 || t == void_type_node
8886 || t == char_type_node
8887 || t == unknown_type_node
8888 || TREE_CODE (t) == NAMESPACE_DECL)
8892 return tsubst_decl (t, args, complain);
8894 if (TREE_CODE (t) == IDENTIFIER_NODE)
8895 type = IDENTIFIER_TYPE_VALUE (t);
8897 type = TREE_TYPE (t);
8899 gcc_assert (type != unknown_type_node);
8901 /* Reuse typedefs. We need to do this to handle dependent attributes,
8902 such as attribute aligned. */
8905 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
8907 tree decl = TYPE_NAME (t);
8909 if (DECL_CLASS_SCOPE_P (decl)
8910 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
8911 && uses_template_parms (DECL_CONTEXT (decl)))
8913 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
8914 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
8915 r = retrieve_specialization (tmpl, gen_args, false);
8917 else if (DECL_FUNCTION_SCOPE_P (decl)
8918 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
8919 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
8920 r = retrieve_local_specialization (decl);
8922 /* The typedef is from a non-template context. */
8928 r = cp_build_qualified_type_real
8929 (r, cp_type_quals (t) | cp_type_quals (r),
8930 complain | tf_ignore_bad_quals);
8933 /* Else we must be instantiating the typedef, so fall through. */
8937 && TREE_CODE (t) != TYPENAME_TYPE
8938 && TREE_CODE (t) != IDENTIFIER_NODE
8939 && TREE_CODE (t) != FUNCTION_TYPE
8940 && TREE_CODE (t) != METHOD_TYPE)
8941 type = tsubst (type, args, complain, in_decl);
8942 if (type == error_mark_node)
8943 return error_mark_node;
8945 switch (TREE_CODE (t))
8950 return tsubst_aggr_type (t, args, complain, in_decl,
8951 /*entering_scope=*/0);
8954 case IDENTIFIER_NODE:
8966 if (t == integer_type_node)
8969 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
8970 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
8974 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
8976 max = tsubst_expr (omax, args, complain, in_decl,
8977 /*integral_constant_expression_p=*/false);
8978 max = fold_decl_constant_value (max);
8980 if (TREE_CODE (max) != INTEGER_CST
8981 && !at_function_scope_p ()
8982 && !value_dependent_expression_p (max))
8984 if (complain & tf_error)
8985 error ("array bound is not an integer constant");
8986 return error_mark_node;
8991 Type deduction may fail for any of the following
8994 Attempting to create an array with a size that is
8995 zero or negative. */
8996 if (integer_zerop (max) && !(complain & tf_error))
8997 /* We must fail if performing argument deduction (as
8998 indicated by the state of complain), so that
8999 another substitution can be found. */
9000 return error_mark_node;
9001 else if (TREE_CODE (max) == INTEGER_CST
9002 && INT_CST_LT (max, integer_zero_node))
9004 if (complain & tf_error)
9005 error ("creating array with negative size (%qE)", max);
9007 return error_mark_node;
9010 return compute_array_index_type (NULL_TREE, max);
9013 case TEMPLATE_TYPE_PARM:
9014 case TEMPLATE_TEMPLATE_PARM:
9015 case BOUND_TEMPLATE_TEMPLATE_PARM:
9016 case TEMPLATE_PARM_INDEX:
9021 tree arg = NULL_TREE;
9025 gcc_assert (TREE_VEC_LENGTH (args) > 0);
9026 template_parm_level_and_index (t, &level, &idx);
9028 levels = TMPL_ARGS_DEPTH (args);
9029 if (level <= levels)
9031 arg = TMPL_ARG (args, level, idx);
9033 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
9034 /* See through ARGUMENT_PACK_SELECT arguments. */
9035 arg = ARGUMENT_PACK_SELECT_ARG (arg);
9038 if (arg == error_mark_node)
9039 return error_mark_node;
9040 else if (arg != NULL_TREE)
9042 if (ARGUMENT_PACK_P (arg))
9043 /* If ARG is an argument pack, we don't actually want to
9044 perform a substitution here, because substitutions
9045 for argument packs are only done
9046 element-by-element. We can get to this point when
9047 substituting the type of a non-type template
9048 parameter pack, when that type actually contains
9049 template parameter packs from an outer template, e.g.,
9051 template<typename... Types> struct A {
9052 template<Types... Values> struct B { };
9056 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
9059 gcc_assert (TYPE_P (arg));
9061 /* cv-quals from the template are discarded when
9062 substituting in a function or reference type. */
9063 if (TREE_CODE (arg) == FUNCTION_TYPE
9064 || TREE_CODE (arg) == METHOD_TYPE
9065 || TREE_CODE (arg) == REFERENCE_TYPE)
9066 quals = cp_type_quals (arg);
9068 quals = cp_type_quals (arg) | cp_type_quals (t);
9070 return cp_build_qualified_type_real
9071 (arg, quals, complain | tf_ignore_bad_quals);
9073 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9075 /* We are processing a type constructed from a
9076 template template parameter. */
9077 tree argvec = tsubst (TYPE_TI_ARGS (t),
9078 args, complain, in_decl);
9079 if (argvec == error_mark_node)
9080 return error_mark_node;
9082 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
9083 are resolving nested-types in the signature of a
9084 member function templates. Otherwise ARG is a
9085 TEMPLATE_DECL and is the real template to be
9087 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
9088 arg = TYPE_NAME (arg);
9090 r = lookup_template_class (arg,
9093 /*entering_scope=*/0,
9095 return cp_build_qualified_type_real
9096 (r, TYPE_QUALS (t), complain);
9099 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
9104 /* This can happen during the attempted tsubst'ing in
9105 unify. This means that we don't yet have any information
9106 about the template parameter in question. */
9109 /* If we get here, we must have been looking at a parm for a
9110 more deeply nested template. Make a new version of this
9111 template parameter, but with a lower level. */
9112 switch (TREE_CODE (t))
9114 case TEMPLATE_TYPE_PARM:
9115 case TEMPLATE_TEMPLATE_PARM:
9116 case BOUND_TEMPLATE_TEMPLATE_PARM:
9117 if (cp_type_quals (t))
9119 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
9120 r = cp_build_qualified_type_real
9121 (r, cp_type_quals (t),
9122 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
9123 ? tf_ignore_bad_quals : 0));
9128 TEMPLATE_TYPE_PARM_INDEX (r)
9129 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
9130 r, levels, args, complain);
9131 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
9132 TYPE_MAIN_VARIANT (r) = r;
9133 TYPE_POINTER_TO (r) = NULL_TREE;
9134 TYPE_REFERENCE_TO (r) = NULL_TREE;
9136 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
9137 /* We have reduced the level of the template
9138 template parameter, but not the levels of its
9139 template parameters, so canonical_type_parameter
9140 will not be able to find the canonical template
9141 template parameter for this level. Thus, we
9142 require structural equality checking to compare
9143 TEMPLATE_TEMPLATE_PARMs. */
9144 SET_TYPE_STRUCTURAL_EQUALITY (r);
9145 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
9146 SET_TYPE_STRUCTURAL_EQUALITY (r);
9148 TYPE_CANONICAL (r) = canonical_type_parameter (r);
9150 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9152 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
9154 if (argvec == error_mark_node)
9155 return error_mark_node;
9157 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
9158 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
9163 case TEMPLATE_PARM_INDEX:
9164 r = reduce_template_parm_level (t, type, levels, args, complain);
9176 tree purpose, value, chain;
9178 if (t == void_list_node)
9181 purpose = TREE_PURPOSE (t);
9184 purpose = tsubst (purpose, args, complain, in_decl);
9185 if (purpose == error_mark_node)
9186 return error_mark_node;
9188 value = TREE_VALUE (t);
9191 value = tsubst (value, args, complain, in_decl);
9192 if (value == error_mark_node)
9193 return error_mark_node;
9195 chain = TREE_CHAIN (t);
9196 if (chain && chain != void_type_node)
9198 chain = tsubst (chain, args, complain, in_decl);
9199 if (chain == error_mark_node)
9200 return error_mark_node;
9202 if (purpose == TREE_PURPOSE (t)
9203 && value == TREE_VALUE (t)
9204 && chain == TREE_CHAIN (t))
9206 return hash_tree_cons (purpose, value, chain);
9210 /* We should never be tsubsting a binfo. */
9214 /* A vector of template arguments. */
9216 return tsubst_template_args (t, args, complain, in_decl);
9219 case REFERENCE_TYPE:
9221 enum tree_code code;
9223 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
9226 code = TREE_CODE (t);
9231 Type deduction may fail for any of the following
9234 -- Attempting to create a pointer to reference type.
9235 -- Attempting to create a reference to a reference type or
9236 a reference to void.
9238 Core issue 106 says that creating a reference to a reference
9239 during instantiation is no longer a cause for failure. We
9240 only enforce this check in strict C++98 mode. */
9241 if ((TREE_CODE (type) == REFERENCE_TYPE
9242 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
9243 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
9245 static location_t last_loc;
9247 /* We keep track of the last time we issued this error
9248 message to avoid spewing a ton of messages during a
9249 single bad template instantiation. */
9250 if (complain & tf_error
9251 && last_loc != input_location)
9253 if (TREE_CODE (type) == VOID_TYPE)
9254 error ("forming reference to void");
9256 error ("forming %s to reference type %qT",
9257 (code == POINTER_TYPE) ? "pointer" : "reference",
9259 last_loc = input_location;
9262 return error_mark_node;
9264 else if (code == POINTER_TYPE)
9266 r = build_pointer_type (type);
9267 if (TREE_CODE (type) == METHOD_TYPE)
9268 r = build_ptrmemfunc_type (r);
9270 else if (TREE_CODE (type) == REFERENCE_TYPE)
9271 /* In C++0x, during template argument substitution, when there is an
9272 attempt to create a reference to a reference type, reference
9273 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
9275 "If a template-argument for a template-parameter T names a type
9276 that is a reference to a type A, an attempt to create the type
9277 'lvalue reference to cv T' creates the type 'lvalue reference to
9278 A,' while an attempt to create the type type rvalue reference to
9279 cv T' creates the type T"
9281 r = cp_build_reference_type
9283 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
9285 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
9286 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
9288 if (r != error_mark_node)
9289 /* Will this ever be needed for TYPE_..._TO values? */
9296 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
9297 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
9301 Type deduction may fail for any of the following
9304 -- Attempting to create "pointer to member of T" when T
9305 is not a class type. */
9306 if (complain & tf_error)
9307 error ("creating pointer to member of non-class type %qT", r);
9308 return error_mark_node;
9310 if (TREE_CODE (type) == REFERENCE_TYPE)
9312 if (complain & tf_error)
9313 error ("creating pointer to member reference type %qT", type);
9314 return error_mark_node;
9316 if (TREE_CODE (type) == VOID_TYPE)
9318 if (complain & tf_error)
9319 error ("creating pointer to member of type void");
9320 return error_mark_node;
9322 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
9323 if (TREE_CODE (type) == FUNCTION_TYPE)
9325 /* The type of the implicit object parameter gets its
9326 cv-qualifiers from the FUNCTION_TYPE. */
9328 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
9329 cp_type_quals (type));
9331 method_type = build_method_type_directly (this_type,
9333 TYPE_ARG_TYPES (type));
9334 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
9335 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
9339 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
9348 fntype = tsubst_function_type (t, args, complain, in_decl);
9349 if (fntype == error_mark_node)
9350 return error_mark_node;
9352 /* Substitute the exception specification. */
9353 specs = tsubst_exception_specification (t, args, complain,
9355 if (specs == error_mark_node)
9356 return error_mark_node;
9358 fntype = build_exception_variant (fntype, specs);
9363 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
9364 if (domain == error_mark_node)
9365 return error_mark_node;
9367 /* As an optimization, we avoid regenerating the array type if
9368 it will obviously be the same as T. */
9369 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
9372 /* These checks should match the ones in grokdeclarator.
9376 The deduction may fail for any of the following reasons:
9378 -- Attempting to create an array with an element type that
9379 is void, a function type, or a reference type, or [DR337]
9380 an abstract class type. */
9381 if (TREE_CODE (type) == VOID_TYPE
9382 || TREE_CODE (type) == FUNCTION_TYPE
9383 || TREE_CODE (type) == REFERENCE_TYPE)
9385 if (complain & tf_error)
9386 error ("creating array of %qT", type);
9387 return error_mark_node;
9389 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
9391 if (complain & tf_error)
9392 error ("creating array of %qT, which is an abstract class type",
9394 return error_mark_node;
9397 r = build_cplus_array_type (type, domain);
9399 if (TYPE_USER_ALIGN (t))
9401 TYPE_ALIGN (r) = TYPE_ALIGN (t);
9402 TYPE_USER_ALIGN (r) = 1;
9411 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9412 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9414 if (e1 == error_mark_node || e2 == error_mark_node)
9415 return error_mark_node;
9417 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
9423 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9424 if (e == error_mark_node)
9425 return error_mark_node;
9427 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
9432 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9433 in_decl, /*entering_scope=*/1);
9434 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
9437 if (ctx == error_mark_node || f == error_mark_node)
9438 return error_mark_node;
9440 if (!MAYBE_CLASS_TYPE_P (ctx))
9442 if (complain & tf_error)
9443 error ("%qT is not a class, struct, or union type", ctx);
9444 return error_mark_node;
9446 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
9448 /* Normally, make_typename_type does not require that the CTX
9449 have complete type in order to allow things like:
9451 template <class T> struct S { typename S<T>::X Y; };
9453 But, such constructs have already been resolved by this
9454 point, so here CTX really should have complete type, unless
9455 it's a partial instantiation. */
9456 ctx = complete_type (ctx);
9457 if (!COMPLETE_TYPE_P (ctx))
9459 if (complain & tf_error)
9460 cxx_incomplete_type_error (NULL_TREE, ctx);
9461 return error_mark_node;
9465 f = make_typename_type (ctx, f, typename_type,
9466 (complain & tf_error) | tf_keep_type_decl);
9467 if (f == error_mark_node)
9469 if (TREE_CODE (f) == TYPE_DECL)
9471 complain |= tf_ignore_bad_quals;
9475 if (TREE_CODE (f) != TYPENAME_TYPE)
9477 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
9478 error ("%qT resolves to %qT, which is not an enumeration type",
9480 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
9481 error ("%qT resolves to %qT, which is is not a class type",
9485 return cp_build_qualified_type_real
9486 (f, cp_type_quals (f) | cp_type_quals (t), complain);
9489 case UNBOUND_CLASS_TEMPLATE:
9491 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9492 in_decl, /*entering_scope=*/1);
9493 tree name = TYPE_IDENTIFIER (t);
9494 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
9496 if (ctx == error_mark_node || name == error_mark_node)
9497 return error_mark_node;
9500 parm_list = tsubst_template_parms (parm_list, args, complain);
9501 return make_unbound_class_template (ctx, name, parm_list, complain);
9511 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9512 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
9513 /*integral_constant_expression_p=*/false);
9514 if (e1 == error_mark_node || e2 == error_mark_node)
9515 return error_mark_node;
9517 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
9522 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9523 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9524 if (e1 == error_mark_node || e2 == error_mark_node)
9525 return error_mark_node;
9527 return build_qualified_name (/*type=*/NULL_TREE,
9528 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
9535 type = finish_typeof (tsubst_expr
9536 (TYPEOF_TYPE_EXPR (t), args,
9538 /*integral_constant_expression_p=*/false));
9539 return cp_build_qualified_type_real (type,
9541 | cp_type_quals (type),
9550 finish_decltype_type (tsubst_expr
9551 (DECLTYPE_TYPE_EXPR (t), args,
9553 /*integral_constant_expression_p=*/false),
9554 DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
9555 return cp_build_qualified_type_real (type,
9557 | cp_type_quals (type),
9561 case TYPE_ARGUMENT_PACK:
9562 case NONTYPE_ARGUMENT_PACK:
9564 tree r = make_node (TREE_CODE (t));
9566 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
9570 SET_ARGUMENT_PACK_ARGS (r, packed_out);
9572 /* For template nontype argument packs, also substitute into
9574 if (TREE_CODE (t) == NONTYPE_ARGUMENT_PACK)
9575 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
9582 sorry ("use of %qs in template",
9583 tree_code_name [(int) TREE_CODE (t)]);
9584 return error_mark_node;
9588 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
9589 type of the expression on the left-hand side of the "." or "->"
9593 tsubst_baselink (tree baselink, tree object_type,
9594 tree args, tsubst_flags_t complain, tree in_decl)
9597 tree qualifying_scope;
9600 tree template_args = 0;
9601 bool template_id_p = false;
9603 /* A baselink indicates a function from a base class. Both the
9604 BASELINK_ACCESS_BINFO and the base class referenced may
9605 indicate bases of the template class, rather than the
9606 instantiated class. In addition, lookups that were not
9607 ambiguous before may be ambiguous now. Therefore, we perform
9608 the lookup again. */
9609 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
9610 qualifying_scope = tsubst (qualifying_scope, args,
9612 fns = BASELINK_FUNCTIONS (baselink);
9613 optype = BASELINK_OPTYPE (baselink);
9614 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
9616 template_id_p = true;
9617 template_args = TREE_OPERAND (fns, 1);
9618 fns = TREE_OPERAND (fns, 0);
9620 template_args = tsubst_template_args (template_args, args,
9623 name = DECL_NAME (get_first_fn (fns));
9624 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
9626 /* If lookup found a single function, mark it as used at this
9627 point. (If it lookup found multiple functions the one selected
9628 later by overload resolution will be marked as used at that
9630 if (BASELINK_P (baselink))
9631 fns = BASELINK_FUNCTIONS (baselink);
9632 if (!template_id_p && !really_overloaded_fn (fns))
9633 mark_used (OVL_CURRENT (fns));
9635 /* Add back the template arguments, if present. */
9636 if (BASELINK_P (baselink) && template_id_p)
9637 BASELINK_FUNCTIONS (baselink)
9638 = build_nt (TEMPLATE_ID_EXPR,
9639 BASELINK_FUNCTIONS (baselink),
9641 /* Update the conversion operator type. */
9642 BASELINK_OPTYPE (baselink)
9643 = tsubst (optype, args, complain, in_decl);
9646 object_type = current_class_type;
9647 return adjust_result_of_qualified_name_lookup (baselink,
9652 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
9653 true if the qualified-id will be a postfix-expression in-and-of
9654 itself; false if more of the postfix-expression follows the
9655 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
9659 tsubst_qualified_id (tree qualified_id, tree args,
9660 tsubst_flags_t complain, tree in_decl,
9661 bool done, bool address_p)
9669 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
9671 /* Figure out what name to look up. */
9672 name = TREE_OPERAND (qualified_id, 1);
9673 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
9676 template_args = TREE_OPERAND (name, 1);
9678 template_args = tsubst_template_args (template_args, args,
9680 name = TREE_OPERAND (name, 0);
9684 is_template = false;
9685 template_args = NULL_TREE;
9688 /* Substitute into the qualifying scope. When there are no ARGS, we
9689 are just trying to simplify a non-dependent expression. In that
9690 case the qualifying scope may be dependent, and, in any case,
9691 substituting will not help. */
9692 scope = TREE_OPERAND (qualified_id, 0);
9695 scope = tsubst (scope, args, complain, in_decl);
9696 expr = tsubst_copy (name, args, complain, in_decl);
9701 if (dependent_type_p (scope))
9702 return build_qualified_name (/*type=*/NULL_TREE,
9704 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
9706 if (!BASELINK_P (name) && !DECL_P (expr))
9708 if (TREE_CODE (expr) == BIT_NOT_EXPR)
9709 /* If this were actually a destructor call, it would have been
9710 parsed as such by the parser. */
9711 expr = error_mark_node;
9713 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
9714 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
9715 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
9717 if (complain & tf_error)
9719 error ("dependent-name %qE is parsed as a non-type, but "
9720 "instantiation yields a type", qualified_id);
9721 inform ("say %<typename %E%> if a type is meant", qualified_id);
9723 return error_mark_node;
9729 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
9731 /* Remember that there was a reference to this entity. */
9735 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
9737 if (complain & tf_error)
9738 qualified_name_lookup_error (scope,
9739 TREE_OPERAND (qualified_id, 1),
9740 expr, input_location);
9741 return error_mark_node;
9745 expr = lookup_template_function (expr, template_args);
9747 if (expr == error_mark_node && complain & tf_error)
9748 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
9749 expr, input_location);
9750 else if (TYPE_P (scope))
9752 expr = (adjust_result_of_qualified_name_lookup
9753 (expr, scope, current_class_type));
9754 expr = (finish_qualified_id_expr
9755 (scope, expr, done, address_p,
9756 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
9757 /*template_arg_p=*/false));
9760 /* Expressions do not generally have reference type. */
9761 if (TREE_CODE (expr) != SCOPE_REF
9762 /* However, if we're about to form a pointer-to-member, we just
9763 want the referenced member referenced. */
9764 && TREE_CODE (expr) != OFFSET_REF)
9765 expr = convert_from_reference (expr);
9770 /* Like tsubst, but deals with expressions. This function just replaces
9771 template parms; to finish processing the resultant expression, use
9775 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9777 enum tree_code code;
9780 if (t == NULL_TREE || t == error_mark_node)
9783 code = TREE_CODE (t);
9788 r = retrieve_local_specialization (t);
9789 gcc_assert (r != NULL);
9790 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
9791 r = ARGUMENT_PACK_SELECT_ARG (r);
9800 if (DECL_TEMPLATE_PARM_P (t))
9801 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
9802 /* There is no need to substitute into namespace-scope
9804 if (DECL_NAMESPACE_SCOPE_P (t))
9806 /* If ARGS is NULL, then T is known to be non-dependent. */
9807 if (args == NULL_TREE)
9808 return integral_constant_value (t);
9810 /* Unfortunately, we cannot just call lookup_name here.
9813 template <int I> int f() {
9815 struct S { void g() { E e = a; } };
9818 When we instantiate f<7>::S::g(), say, lookup_name is not
9819 clever enough to find f<7>::a. */
9821 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
9822 /*entering_scope=*/0);
9824 for (v = TYPE_VALUES (enum_type);
9827 if (TREE_PURPOSE (v) == DECL_NAME (t))
9828 return TREE_VALUE (v);
9830 /* We didn't find the name. That should never happen; if
9831 name-lookup found it during preliminary parsing, we
9832 should find it again here during instantiation. */
9838 if (DECL_CONTEXT (t))
9842 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
9843 /*entering_scope=*/1);
9844 if (ctx != DECL_CONTEXT (t))
9846 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
9849 if (complain & tf_error)
9850 error ("using invalid field %qD", t);
9851 return error_mark_node;
9861 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
9862 || local_variable_p (t))
9863 t = tsubst (t, args, complain, in_decl);
9868 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
9871 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9872 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
9873 args, complain, in_decl);
9874 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
9875 return tsubst (t, args, complain, in_decl);
9876 else if (DECL_CLASS_SCOPE_P (t)
9877 && uses_template_parms (DECL_CONTEXT (t)))
9879 /* Template template argument like the following example need
9882 template <template <class> class TT> struct C {};
9883 template <class T> struct D {
9884 template <class U> struct E {};
9889 We are processing the template argument `E' in #1 for
9890 the template instantiation #2. Originally, `E' is a
9891 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
9892 have to substitute this with one having context `D<int>'. */
9894 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
9895 return lookup_field (context, DECL_NAME(t), 0, false);
9898 /* Ordinary template template argument. */
9902 case REINTERPRET_CAST_EXPR:
9903 case CONST_CAST_EXPR:
9904 case STATIC_CAST_EXPR:
9905 case DYNAMIC_CAST_EXPR:
9908 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
9909 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
9912 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
9914 /* We only want to compute the number of arguments. */
9915 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
9919 if (TREE_CODE (expanded) == TREE_VEC)
9920 len = TREE_VEC_LENGTH (expanded);
9922 if (expanded == error_mark_node)
9923 return error_mark_node;
9924 else if (PACK_EXPANSION_P (expanded)
9925 || (TREE_CODE (expanded) == TREE_VEC
9927 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
9929 if (TREE_CODE (expanded) == TREE_VEC)
9930 expanded = TREE_VEC_ELT (expanded, len - 1);
9932 if (TYPE_P (expanded))
9933 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
9934 complain & tf_error);
9936 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
9937 complain & tf_error);
9940 return build_int_cst (size_type_node, len);
9946 case TRUTH_NOT_EXPR:
9949 case UNARY_PLUS_EXPR: /* Unary + */
9957 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
9958 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
9965 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
9966 name = TREE_OPERAND (t, 1);
9967 if (TREE_CODE (name) == BIT_NOT_EXPR)
9969 name = tsubst_copy (TREE_OPERAND (name, 0), args,
9971 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
9973 else if (TREE_CODE (name) == SCOPE_REF
9974 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
9976 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
9978 name = TREE_OPERAND (name, 1);
9979 name = tsubst_copy (TREE_OPERAND (name, 0), args,
9981 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
9982 name = build_qualified_name (/*type=*/NULL_TREE,
9984 /*template_p=*/false);
9986 else if (TREE_CODE (name) == BASELINK)
9987 name = tsubst_baselink (name,
9988 non_reference (TREE_TYPE (object)),
9992 name = tsubst_copy (name, args, complain, in_decl);
9993 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
9999 case TRUNC_DIV_EXPR:
10000 case CEIL_DIV_EXPR:
10001 case FLOOR_DIV_EXPR:
10002 case ROUND_DIV_EXPR:
10003 case EXACT_DIV_EXPR:
10007 case TRUNC_MOD_EXPR:
10008 case FLOOR_MOD_EXPR:
10009 case TRUTH_ANDIF_EXPR:
10010 case TRUTH_ORIF_EXPR:
10011 case TRUTH_AND_EXPR:
10012 case TRUTH_OR_EXPR:
10025 case COMPOUND_EXPR:
10028 case PREDECREMENT_EXPR:
10029 case PREINCREMENT_EXPR:
10030 case POSTDECREMENT_EXPR:
10031 case POSTINCREMENT_EXPR:
10033 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10034 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10037 return build_qualified_name (/*type=*/NULL_TREE,
10038 tsubst_copy (TREE_OPERAND (t, 0),
10039 args, complain, in_decl),
10040 tsubst_copy (TREE_OPERAND (t, 1),
10041 args, complain, in_decl),
10042 QUALIFIED_NAME_IS_TEMPLATE (t));
10047 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10048 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10049 NULL_TREE, NULL_TREE);
10053 int n = VL_EXP_OPERAND_LENGTH (t);
10054 tree result = build_vl_exp (CALL_EXPR, n);
10056 for (i = 0; i < n; i++)
10057 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
10058 complain, in_decl);
10064 case PSEUDO_DTOR_EXPR:
10067 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10068 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10069 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10070 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
10077 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10078 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10079 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10080 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
10087 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10088 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10089 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
10090 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
10094 case TEMPLATE_ID_EXPR:
10096 /* Substituted template arguments */
10097 tree fn = TREE_OPERAND (t, 0);
10098 tree targs = TREE_OPERAND (t, 1);
10100 fn = tsubst_copy (fn, args, complain, in_decl);
10102 targs = tsubst_template_args (targs, args, complain, in_decl);
10104 return lookup_template_function (fn, targs);
10109 tree purpose, value, chain;
10111 if (t == void_list_node)
10114 purpose = TREE_PURPOSE (t);
10116 purpose = tsubst_copy (purpose, args, complain, in_decl);
10117 value = TREE_VALUE (t);
10119 value = tsubst_copy (value, args, complain, in_decl);
10120 chain = TREE_CHAIN (t);
10121 if (chain && chain != void_type_node)
10122 chain = tsubst_copy (chain, args, complain, in_decl);
10123 if (purpose == TREE_PURPOSE (t)
10124 && value == TREE_VALUE (t)
10125 && chain == TREE_CHAIN (t))
10127 return tree_cons (purpose, value, chain);
10132 case ENUMERAL_TYPE:
10134 case TEMPLATE_TYPE_PARM:
10135 case TEMPLATE_TEMPLATE_PARM:
10136 case BOUND_TEMPLATE_TEMPLATE_PARM:
10137 case TEMPLATE_PARM_INDEX:
10139 case REFERENCE_TYPE:
10141 case FUNCTION_TYPE:
10144 case TYPENAME_TYPE:
10145 case UNBOUND_CLASS_TEMPLATE:
10147 case DECLTYPE_TYPE:
10149 return tsubst (t, args, complain, in_decl);
10151 case IDENTIFIER_NODE:
10152 if (IDENTIFIER_TYPENAME_P (t))
10154 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10155 return mangle_conv_op_name_for_type (new_type);
10161 /* This is handled by tsubst_copy_and_build. */
10162 gcc_unreachable ();
10165 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
10167 tsubst (TREE_TYPE (t), args, complain, in_decl));
10169 case CLEANUP_POINT_EXPR:
10170 /* We shouldn't have built any of these during initial template
10171 generation. Instead, they should be built during instantiation
10172 in response to the saved STMT_IS_FULL_EXPR_P setting. */
10173 gcc_unreachable ();
10176 mark_used (TREE_OPERAND (t, 1));
10179 case EXPR_PACK_EXPANSION:
10180 error ("invalid use of pack expansion expression");
10181 return error_mark_node;
10183 case NONTYPE_ARGUMENT_PACK:
10184 error ("use %<...%> to expand argument pack");
10185 return error_mark_node;
10192 /* Like tsubst_copy, but specifically for OpenMP clauses. */
10195 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
10198 tree new_clauses = NULL, nc, oc;
10200 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
10202 nc = copy_node (oc);
10203 OMP_CLAUSE_CHAIN (nc) = new_clauses;
10206 switch (OMP_CLAUSE_CODE (nc))
10208 case OMP_CLAUSE_LASTPRIVATE:
10209 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
10211 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
10212 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
10213 in_decl, /*integral_constant_expression_p=*/false);
10214 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
10215 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
10218 case OMP_CLAUSE_PRIVATE:
10219 case OMP_CLAUSE_SHARED:
10220 case OMP_CLAUSE_FIRSTPRIVATE:
10221 case OMP_CLAUSE_REDUCTION:
10222 case OMP_CLAUSE_COPYIN:
10223 case OMP_CLAUSE_COPYPRIVATE:
10224 case OMP_CLAUSE_IF:
10225 case OMP_CLAUSE_NUM_THREADS:
10226 case OMP_CLAUSE_SCHEDULE:
10227 case OMP_CLAUSE_COLLAPSE:
10228 OMP_CLAUSE_OPERAND (nc, 0)
10229 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
10230 in_decl, /*integral_constant_expression_p=*/false);
10232 case OMP_CLAUSE_NOWAIT:
10233 case OMP_CLAUSE_ORDERED:
10234 case OMP_CLAUSE_DEFAULT:
10235 case OMP_CLAUSE_UNTIED:
10238 gcc_unreachable ();
10242 return finish_omp_clauses (nreverse (new_clauses));
10245 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
10248 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
10251 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
10253 tree purpose, value, chain;
10258 if (TREE_CODE (t) != TREE_LIST)
10259 return tsubst_copy_and_build (t, args, complain, in_decl,
10260 /*function_p=*/false,
10261 /*integral_constant_expression_p=*/false);
10263 if (t == void_list_node)
10266 purpose = TREE_PURPOSE (t);
10268 purpose = RECUR (purpose);
10269 value = TREE_VALUE (t);
10271 value = RECUR (value);
10272 chain = TREE_CHAIN (t);
10273 if (chain && chain != void_type_node)
10274 chain = RECUR (chain);
10275 return tree_cons (purpose, value, chain);
10279 /* Substitute one OMP_FOR iterator. */
10282 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
10283 tree condv, tree incrv, tree *clauses,
10284 tree args, tsubst_flags_t complain, tree in_decl,
10285 bool integral_constant_expression_p)
10287 #define RECUR(NODE) \
10288 tsubst_expr ((NODE), args, complain, in_decl, \
10289 integral_constant_expression_p)
10290 tree decl, init, cond, incr;
10292 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
10293 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
10294 decl = RECUR (TREE_OPERAND (init, 0));
10295 init = TREE_OPERAND (init, 1);
10296 gcc_assert (!type_dependent_expression_p (decl));
10298 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
10300 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
10301 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
10302 if (TREE_CODE (incr) == MODIFY_EXPR)
10303 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
10304 RECUR (TREE_OPERAND (incr, 1)),
10307 incr = RECUR (incr);
10308 TREE_VEC_ELT (declv, i) = decl;
10309 TREE_VEC_ELT (initv, i) = init;
10310 TREE_VEC_ELT (condv, i) = cond;
10311 TREE_VEC_ELT (incrv, i) = incr;
10315 if (init && TREE_CODE (init) != DECL_EXPR)
10318 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
10320 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
10321 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
10322 && OMP_CLAUSE_DECL (c) == decl)
10324 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
10325 && OMP_CLAUSE_DECL (c) == decl)
10326 error ("iteration variable %qD should not be firstprivate", decl);
10327 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
10328 && OMP_CLAUSE_DECL (c) == decl)
10329 error ("iteration variable %qD should not be reduction", decl);
10333 c = build_omp_clause (OMP_CLAUSE_PRIVATE);
10334 OMP_CLAUSE_DECL (c) = decl;
10335 c = finish_omp_clauses (c);
10338 OMP_CLAUSE_CHAIN (c) = *clauses;
10343 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
10344 if (COMPARISON_CLASS_P (cond))
10345 cond = build2 (TREE_CODE (cond), boolean_type_node,
10346 RECUR (TREE_OPERAND (cond, 0)),
10347 RECUR (TREE_OPERAND (cond, 1)));
10349 cond = RECUR (cond);
10350 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
10351 switch (TREE_CODE (incr))
10353 case PREINCREMENT_EXPR:
10354 case PREDECREMENT_EXPR:
10355 case POSTINCREMENT_EXPR:
10356 case POSTDECREMENT_EXPR:
10357 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
10358 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
10361 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
10362 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
10364 tree rhs = TREE_OPERAND (incr, 1);
10365 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
10366 RECUR (TREE_OPERAND (incr, 0)),
10367 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
10368 RECUR (TREE_OPERAND (rhs, 0)),
10369 RECUR (TREE_OPERAND (rhs, 1))));
10372 incr = RECUR (incr);
10375 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
10376 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
10378 tree lhs = RECUR (TREE_OPERAND (incr, 0));
10379 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
10380 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
10381 TREE_TYPE (decl), lhs,
10382 RECUR (TREE_OPERAND (incr, 2))));
10384 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
10385 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
10386 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
10388 tree rhs = TREE_OPERAND (incr, 2);
10389 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
10390 RECUR (TREE_OPERAND (incr, 0)),
10391 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
10392 RECUR (TREE_OPERAND (rhs, 0)),
10393 RECUR (TREE_OPERAND (rhs, 1))));
10396 incr = RECUR (incr);
10399 incr = RECUR (incr);
10403 TREE_VEC_ELT (declv, i) = decl;
10404 TREE_VEC_ELT (initv, i) = init;
10405 TREE_VEC_ELT (condv, i) = cond;
10406 TREE_VEC_ELT (incrv, i) = incr;
10410 /* Like tsubst_copy for expressions, etc. but also does semantic
10414 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
10415 bool integral_constant_expression_p)
10417 #define RECUR(NODE) \
10418 tsubst_expr ((NODE), args, complain, in_decl, \
10419 integral_constant_expression_p)
10423 if (t == NULL_TREE || t == error_mark_node)
10426 if (EXPR_HAS_LOCATION (t))
10427 input_location = EXPR_LOCATION (t);
10428 if (STATEMENT_CODE_P (TREE_CODE (t)))
10429 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
10431 switch (TREE_CODE (t))
10433 case STATEMENT_LIST:
10435 tree_stmt_iterator i;
10436 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
10437 RECUR (tsi_stmt (i));
10441 case CTOR_INITIALIZER:
10442 finish_mem_initializers (tsubst_initializer_list
10443 (TREE_OPERAND (t, 0), args));
10447 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
10451 tmp = RECUR (EXPR_STMT_EXPR (t));
10452 if (EXPR_STMT_STMT_EXPR_RESULT (t))
10453 finish_stmt_expr_expr (tmp, cur_stmt_expr);
10455 finish_expr_stmt (tmp);
10459 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
10467 decl = DECL_EXPR_DECL (t);
10468 if (TREE_CODE (decl) == LABEL_DECL)
10469 finish_label_decl (DECL_NAME (decl));
10470 else if (TREE_CODE (decl) == USING_DECL)
10472 tree scope = USING_DECL_SCOPE (decl);
10473 tree name = DECL_NAME (decl);
10476 scope = RECUR (scope);
10477 decl = lookup_qualified_name (scope, name,
10478 /*is_type_p=*/false,
10479 /*complain=*/false);
10480 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
10481 qualified_name_lookup_error (scope, name, decl, input_location);
10483 do_local_using_decl (decl, scope, name);
10487 init = DECL_INITIAL (decl);
10488 decl = tsubst (decl, args, complain, in_decl);
10489 if (decl != error_mark_node)
10491 /* By marking the declaration as instantiated, we avoid
10492 trying to instantiate it. Since instantiate_decl can't
10493 handle local variables, and since we've already done
10494 all that needs to be done, that's the right thing to
10496 if (TREE_CODE (decl) == VAR_DECL)
10497 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
10498 if (TREE_CODE (decl) == VAR_DECL
10499 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
10500 /* Anonymous aggregates are a special case. */
10501 finish_anon_union (decl);
10504 maybe_push_decl (decl);
10505 if (TREE_CODE (decl) == VAR_DECL
10506 && DECL_PRETTY_FUNCTION_P (decl))
10508 /* For __PRETTY_FUNCTION__ we have to adjust the
10510 const char *const name
10511 = cxx_printable_name (current_function_decl, 2);
10512 init = cp_fname_init (name, &TREE_TYPE (decl));
10516 tree t = RECUR (init);
10519 /* If we had an initializer but it
10520 instantiated to nothing,
10521 value-initialize the object. This will
10522 only occur when the initializer was a
10523 pack expansion where the parameter packs
10524 used in that expansion were of length
10526 init = build_default_init (TREE_TYPE (decl),
10532 finish_decl (decl, init, NULL_TREE);
10537 /* A DECL_EXPR can also be used as an expression, in the condition
10538 clause of an if/for/while construct. */
10543 stmt = begin_for_stmt ();
10544 RECUR (FOR_INIT_STMT (t));
10545 finish_for_init_stmt (stmt);
10546 tmp = RECUR (FOR_COND (t));
10547 finish_for_cond (tmp, stmt);
10548 tmp = RECUR (FOR_EXPR (t));
10549 finish_for_expr (tmp, stmt);
10550 RECUR (FOR_BODY (t));
10551 finish_for_stmt (stmt);
10555 stmt = begin_while_stmt ();
10556 tmp = RECUR (WHILE_COND (t));
10557 finish_while_stmt_cond (tmp, stmt);
10558 RECUR (WHILE_BODY (t));
10559 finish_while_stmt (stmt);
10563 stmt = begin_do_stmt ();
10564 RECUR (DO_BODY (t));
10565 finish_do_body (stmt);
10566 tmp = RECUR (DO_COND (t));
10567 finish_do_stmt (tmp, stmt);
10571 stmt = begin_if_stmt ();
10572 tmp = RECUR (IF_COND (t));
10573 finish_if_stmt_cond (tmp, stmt);
10574 RECUR (THEN_CLAUSE (t));
10575 finish_then_clause (stmt);
10577 if (ELSE_CLAUSE (t))
10579 begin_else_clause (stmt);
10580 RECUR (ELSE_CLAUSE (t));
10581 finish_else_clause (stmt);
10584 finish_if_stmt (stmt);
10588 if (BIND_EXPR_BODY_BLOCK (t))
10589 stmt = begin_function_body ();
10591 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
10592 ? BCS_TRY_BLOCK : 0);
10594 RECUR (BIND_EXPR_BODY (t));
10596 if (BIND_EXPR_BODY_BLOCK (t))
10597 finish_function_body (stmt);
10599 finish_compound_stmt (stmt);
10603 finish_break_stmt ();
10606 case CONTINUE_STMT:
10607 finish_continue_stmt ();
10611 stmt = begin_switch_stmt ();
10612 tmp = RECUR (SWITCH_STMT_COND (t));
10613 finish_switch_cond (tmp, stmt);
10614 RECUR (SWITCH_STMT_BODY (t));
10615 finish_switch_stmt (stmt);
10618 case CASE_LABEL_EXPR:
10619 finish_case_label (RECUR (CASE_LOW (t)),
10620 RECUR (CASE_HIGH (t)));
10624 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
10628 tmp = GOTO_DESTINATION (t);
10629 if (TREE_CODE (tmp) != LABEL_DECL)
10630 /* Computed goto's must be tsubst'd into. On the other hand,
10631 non-computed gotos must not be; the identifier in question
10632 will have no binding. */
10635 tmp = DECL_NAME (tmp);
10636 finish_goto_stmt (tmp);
10640 tmp = finish_asm_stmt
10641 (ASM_VOLATILE_P (t),
10642 RECUR (ASM_STRING (t)),
10643 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
10644 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
10645 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl));
10647 tree asm_expr = tmp;
10648 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
10649 asm_expr = TREE_OPERAND (asm_expr, 0);
10650 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
10657 stmt = begin_try_block ();
10658 RECUR (TRY_STMTS (t));
10659 finish_cleanup_try_block (stmt);
10660 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
10664 tree compound_stmt = NULL_TREE;
10666 if (FN_TRY_BLOCK_P (t))
10667 stmt = begin_function_try_block (&compound_stmt);
10669 stmt = begin_try_block ();
10671 RECUR (TRY_STMTS (t));
10673 if (FN_TRY_BLOCK_P (t))
10674 finish_function_try_block (stmt);
10676 finish_try_block (stmt);
10678 RECUR (TRY_HANDLERS (t));
10679 if (FN_TRY_BLOCK_P (t))
10680 finish_function_handler_sequence (stmt, compound_stmt);
10682 finish_handler_sequence (stmt);
10688 tree decl = HANDLER_PARMS (t);
10692 decl = tsubst (decl, args, complain, in_decl);
10693 /* Prevent instantiate_decl from trying to instantiate
10694 this variable. We've already done all that needs to be
10696 if (decl != error_mark_node)
10697 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
10699 stmt = begin_handler ();
10700 finish_handler_parms (decl, stmt);
10701 RECUR (HANDLER_BODY (t));
10702 finish_handler (stmt);
10707 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
10710 case STATIC_ASSERT:
10713 tsubst_expr (STATIC_ASSERT_CONDITION (t),
10716 /*integral_constant_expression_p=*/true);
10717 finish_static_assert (condition,
10718 STATIC_ASSERT_MESSAGE (t),
10719 STATIC_ASSERT_SOURCE_LOCATION (t),
10720 /*member_p=*/false);
10725 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
10726 args, complain, in_decl);
10727 stmt = begin_omp_parallel ();
10728 RECUR (OMP_PARALLEL_BODY (t));
10729 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
10730 = OMP_PARALLEL_COMBINED (t);
10734 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
10735 args, complain, in_decl);
10736 stmt = begin_omp_task ();
10737 RECUR (OMP_TASK_BODY (t));
10738 finish_omp_task (tmp, stmt);
10743 tree clauses, body, pre_body;
10744 tree declv, initv, condv, incrv;
10747 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
10748 args, complain, in_decl);
10749 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
10750 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
10751 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
10752 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
10754 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
10755 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
10756 &clauses, args, complain, in_decl,
10757 integral_constant_expression_p);
10759 stmt = begin_omp_structured_block ();
10761 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
10762 if (TREE_VEC_ELT (initv, i) == NULL
10763 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
10764 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
10765 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
10767 tree init = RECUR (TREE_VEC_ELT (initv, i));
10768 gcc_assert (init == TREE_VEC_ELT (declv, i));
10769 TREE_VEC_ELT (initv, i) = NULL_TREE;
10773 tree decl_expr = TREE_VEC_ELT (initv, i);
10774 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
10775 gcc_assert (init != NULL);
10776 TREE_VEC_ELT (initv, i) = RECUR (init);
10777 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
10779 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
10782 pre_body = push_stmt_list ();
10783 RECUR (OMP_FOR_PRE_BODY (t));
10784 pre_body = pop_stmt_list (pre_body);
10786 body = push_stmt_list ();
10787 RECUR (OMP_FOR_BODY (t));
10788 body = pop_stmt_list (body);
10790 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
10791 body, pre_body, clauses);
10793 add_stmt (finish_omp_structured_block (stmt));
10799 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
10800 stmt = push_stmt_list ();
10801 RECUR (OMP_BODY (t));
10802 stmt = pop_stmt_list (stmt);
10805 OMP_BODY (t) = stmt;
10806 OMP_CLAUSES (t) = tmp;
10814 stmt = push_stmt_list ();
10815 RECUR (OMP_BODY (t));
10816 stmt = pop_stmt_list (stmt);
10819 OMP_BODY (t) = stmt;
10824 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
10826 tree op1 = TREE_OPERAND (t, 1);
10827 tree lhs = RECUR (TREE_OPERAND (op1, 0));
10828 tree rhs = RECUR (TREE_OPERAND (op1, 1));
10829 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
10833 case EXPR_PACK_EXPANSION:
10834 error ("invalid use of pack expansion expression");
10835 return error_mark_node;
10837 case NONTYPE_ARGUMENT_PACK:
10838 error ("use %<...%> to expand argument pack");
10839 return error_mark_node;
10842 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
10844 return tsubst_copy_and_build (t, args, complain, in_decl,
10845 /*function_p=*/false,
10846 integral_constant_expression_p);
10853 /* T is a postfix-expression that is not being used in a function
10854 call. Return the substituted version of T. */
10857 tsubst_non_call_postfix_expression (tree t, tree args,
10858 tsubst_flags_t complain,
10861 if (TREE_CODE (t) == SCOPE_REF)
10862 t = tsubst_qualified_id (t, args, complain, in_decl,
10863 /*done=*/false, /*address_p=*/false);
10865 t = tsubst_copy_and_build (t, args, complain, in_decl,
10866 /*function_p=*/false,
10867 /*integral_constant_expression_p=*/false);
10872 /* Like tsubst but deals with expressions and performs semantic
10873 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
10876 tsubst_copy_and_build (tree t,
10878 tsubst_flags_t complain,
10881 bool integral_constant_expression_p)
10883 #define RECUR(NODE) \
10884 tsubst_copy_and_build (NODE, args, complain, in_decl, \
10885 /*function_p=*/false, \
10886 integral_constant_expression_p)
10890 if (t == NULL_TREE || t == error_mark_node)
10893 switch (TREE_CODE (t))
10897 /* Fall through. */
10898 case IDENTIFIER_NODE:
10902 bool non_integral_constant_expression_p;
10903 const char *error_msg;
10905 if (IDENTIFIER_TYPENAME_P (t))
10907 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10908 t = mangle_conv_op_name_for_type (new_type);
10911 /* Look up the name. */
10912 decl = lookup_name (t);
10914 /* By convention, expressions use ERROR_MARK_NODE to indicate
10915 failure, not NULL_TREE. */
10916 if (decl == NULL_TREE)
10917 decl = error_mark_node;
10919 decl = finish_id_expression (t, decl, NULL_TREE,
10921 integral_constant_expression_p,
10922 /*allow_non_integral_constant_expression_p=*/false,
10923 &non_integral_constant_expression_p,
10924 /*template_p=*/false,
10926 /*address_p=*/false,
10927 /*template_arg_p=*/false,
10932 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
10933 decl = unqualified_name_lookup_error (decl);
10937 case TEMPLATE_ID_EXPR:
10940 tree templ = RECUR (TREE_OPERAND (t, 0));
10941 tree targs = TREE_OPERAND (t, 1);
10944 targs = tsubst_template_args (targs, args, complain, in_decl);
10946 if (TREE_CODE (templ) == COMPONENT_REF)
10948 object = TREE_OPERAND (templ, 0);
10949 templ = TREE_OPERAND (templ, 1);
10952 object = NULL_TREE;
10953 templ = lookup_template_function (templ, targs);
10956 return build3 (COMPONENT_REF, TREE_TYPE (templ),
10957 object, templ, NULL_TREE);
10959 return baselink_for_fns (templ);
10964 tree r = RECUR (TREE_OPERAND (t, 0));
10966 if (REFERENCE_REF_P (t))
10968 /* A type conversion to reference type will be enclosed in
10969 such an indirect ref, but the substitution of the cast
10970 will have also added such an indirect ref. */
10971 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
10972 r = convert_from_reference (r);
10975 r = build_x_indirect_ref (r, "unary *", complain);
10981 (tsubst (TREE_TYPE (t), args, complain, in_decl),
10982 RECUR (TREE_OPERAND (t, 0)));
10985 case REINTERPRET_CAST_EXPR:
10986 case CONST_CAST_EXPR:
10987 case DYNAMIC_CAST_EXPR:
10988 case STATIC_CAST_EXPR:
10993 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10994 if (integral_constant_expression_p
10995 && !cast_valid_in_integral_constant_expression_p (type))
10997 if (complain & tf_error)
10998 error ("a cast to a type other than an integral or "
10999 "enumeration type cannot appear in a constant-expression");
11000 return error_mark_node;
11003 op = RECUR (TREE_OPERAND (t, 0));
11005 switch (TREE_CODE (t))
11008 return build_functional_cast (type, op, complain);
11009 case REINTERPRET_CAST_EXPR:
11010 return build_reinterpret_cast (type, op, complain);
11011 case CONST_CAST_EXPR:
11012 return build_const_cast (type, op, complain);
11013 case DYNAMIC_CAST_EXPR:
11014 return build_dynamic_cast (type, op, complain);
11015 case STATIC_CAST_EXPR:
11016 return build_static_cast (type, op, complain);
11018 gcc_unreachable ();
11022 case POSTDECREMENT_EXPR:
11023 case POSTINCREMENT_EXPR:
11024 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11025 args, complain, in_decl);
11026 return build_x_unary_op (TREE_CODE (t), op1, complain);
11028 case PREDECREMENT_EXPR:
11029 case PREINCREMENT_EXPR:
11033 case TRUTH_NOT_EXPR:
11034 case UNARY_PLUS_EXPR: /* Unary + */
11035 case REALPART_EXPR:
11036 case IMAGPART_EXPR:
11037 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
11041 op1 = TREE_OPERAND (t, 0);
11042 if (TREE_CODE (op1) == SCOPE_REF)
11043 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
11044 /*done=*/true, /*address_p=*/true);
11046 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
11048 if (TREE_CODE (op1) == LABEL_DECL)
11049 return finish_label_address_expr (DECL_NAME (op1));
11050 return build_x_unary_op (ADDR_EXPR, op1, complain);
11055 case TRUNC_DIV_EXPR:
11056 case CEIL_DIV_EXPR:
11057 case FLOOR_DIV_EXPR:
11058 case ROUND_DIV_EXPR:
11059 case EXACT_DIV_EXPR:
11063 case TRUNC_MOD_EXPR:
11064 case FLOOR_MOD_EXPR:
11065 case TRUTH_ANDIF_EXPR:
11066 case TRUTH_ORIF_EXPR:
11067 case TRUTH_AND_EXPR:
11068 case TRUTH_OR_EXPR:
11083 return build_x_binary_op
11085 RECUR (TREE_OPERAND (t, 0)),
11086 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
11088 : TREE_CODE (TREE_OPERAND (t, 0))),
11089 RECUR (TREE_OPERAND (t, 1)),
11090 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
11092 : TREE_CODE (TREE_OPERAND (t, 1))),
11093 /*overloaded_p=*/NULL,
11097 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
11098 /*address_p=*/false);
11100 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11101 args, complain, in_decl);
11102 return build_x_binary_op (ARRAY_REF, op1,
11103 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
11105 : TREE_CODE (TREE_OPERAND (t, 0))),
11106 RECUR (TREE_OPERAND (t, 1)),
11107 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
11109 : TREE_CODE (TREE_OPERAND (t, 1))),
11110 /*overloaded_p=*/NULL,
11114 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11115 return tsubst_copy (t, args, complain, in_decl);
11119 op1 = TREE_OPERAND (t, 0);
11122 /* When there are no ARGS, we are trying to evaluate a
11123 non-dependent expression from the parser. Trying to do
11124 the substitutions may not work. */
11126 op1 = TREE_TYPE (op1);
11131 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
11132 /*function_p=*/false,
11133 /*integral_constant_expression_p=*/false);
11137 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
11138 complain & tf_error);
11140 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
11141 complain & tf_error);
11145 tree r = build_x_modify_expr
11146 (RECUR (TREE_OPERAND (t, 0)),
11147 TREE_CODE (TREE_OPERAND (t, 1)),
11148 RECUR (TREE_OPERAND (t, 2)),
11150 /* TREE_NO_WARNING must be set if either the expression was
11151 parenthesized or it uses an operator such as >>= rather
11152 than plain assignment. In the former case, it was already
11153 set and must be copied. In the latter case,
11154 build_x_modify_expr sets it and it must not be reset
11156 if (TREE_NO_WARNING (t))
11157 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11162 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11163 args, complain, in_decl);
11164 /* Remember that there was a reference to this entity. */
11167 return build_x_arrow (op1);
11171 tree init = RECUR (TREE_OPERAND (t, 3));
11173 if (TREE_OPERAND (t, 3) && !init)
11174 /* If there was an initializer in the original tree, but
11175 it instantiated to an empty list, then we should pass on
11176 VOID_ZERO_NODE to tell build_new that it was an empty
11177 initializer () rather than no initializer. This can only
11178 happen when the initializer is a pack expansion whose
11179 parameter packs are of length zero. */
11180 init = void_zero_node;
11183 (RECUR (TREE_OPERAND (t, 0)),
11184 RECUR (TREE_OPERAND (t, 1)),
11185 RECUR (TREE_OPERAND (t, 2)),
11187 NEW_EXPR_USE_GLOBAL (t),
11192 return delete_sanity
11193 (RECUR (TREE_OPERAND (t, 0)),
11194 RECUR (TREE_OPERAND (t, 1)),
11195 DELETE_EXPR_USE_VEC (t),
11196 DELETE_EXPR_USE_GLOBAL (t));
11198 case COMPOUND_EXPR:
11199 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
11200 RECUR (TREE_OPERAND (t, 1)),
11210 function = CALL_EXPR_FN (t);
11211 /* When we parsed the expression, we determined whether or
11212 not Koenig lookup should be performed. */
11213 koenig_p = KOENIG_LOOKUP_P (t);
11214 if (TREE_CODE (function) == SCOPE_REF)
11216 qualified_p = true;
11217 function = tsubst_qualified_id (function, args, complain, in_decl,
11219 /*address_p=*/false);
11223 if (TREE_CODE (function) == COMPONENT_REF)
11225 tree op = TREE_OPERAND (function, 1);
11227 qualified_p = (TREE_CODE (op) == SCOPE_REF
11228 || (BASELINK_P (op)
11229 && BASELINK_QUALIFIED_P (op)));
11232 qualified_p = false;
11234 function = tsubst_copy_and_build (function, args, complain,
11237 integral_constant_expression_p);
11239 if (BASELINK_P (function))
11240 qualified_p = true;
11243 /* FIXME: Rewrite this so as not to construct an arglist. */
11244 call_args = RECUR (CALL_EXPR_ARGS (t));
11246 /* We do not perform argument-dependent lookup if normal
11247 lookup finds a non-function, in accordance with the
11248 expected resolution of DR 218. */
11250 && ((is_overloaded_fn (function)
11251 /* If lookup found a member function, the Koenig lookup is
11252 not appropriate, even if an unqualified-name was used
11253 to denote the function. */
11254 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
11255 || TREE_CODE (function) == IDENTIFIER_NODE))
11256 function = perform_koenig_lookup (function, call_args);
11258 if (TREE_CODE (function) == IDENTIFIER_NODE)
11260 unqualified_name_lookup_error (function);
11261 return error_mark_node;
11264 /* Remember that there was a reference to this entity. */
11265 if (DECL_P (function))
11266 mark_used (function);
11268 if (TREE_CODE (function) == OFFSET_REF)
11269 return build_offset_ref_call_from_tree (function, call_args);
11270 if (TREE_CODE (function) == COMPONENT_REF)
11272 if (!BASELINK_P (TREE_OPERAND (function, 1)))
11273 return finish_call_expr (function, call_args,
11274 /*disallow_virtual=*/false,
11275 /*koenig_p=*/false,
11278 return (build_new_method_call
11279 (TREE_OPERAND (function, 0),
11280 TREE_OPERAND (function, 1),
11281 call_args, NULL_TREE,
11282 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
11286 return finish_call_expr (function, call_args,
11287 /*disallow_virtual=*/qualified_p,
11293 return build_x_conditional_expr
11294 (RECUR (TREE_OPERAND (t, 0)),
11295 RECUR (TREE_OPERAND (t, 1)),
11296 RECUR (TREE_OPERAND (t, 2)),
11299 case PSEUDO_DTOR_EXPR:
11300 return finish_pseudo_destructor_expr
11301 (RECUR (TREE_OPERAND (t, 0)),
11302 RECUR (TREE_OPERAND (t, 1)),
11303 RECUR (TREE_OPERAND (t, 2)));
11307 tree purpose, value, chain;
11309 if (t == void_list_node)
11312 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
11313 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
11315 /* We have pack expansions, so expand those and
11316 create a new list out of it. */
11317 tree purposevec = NULL_TREE;
11318 tree valuevec = NULL_TREE;
11322 /* Expand the argument expressions. */
11323 if (TREE_PURPOSE (t))
11324 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
11325 complain, in_decl);
11326 if (TREE_VALUE (t))
11327 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
11328 complain, in_decl);
11330 /* Build the rest of the list. */
11331 chain = TREE_CHAIN (t);
11332 if (chain && chain != void_type_node)
11333 chain = RECUR (chain);
11335 /* Determine the number of arguments. */
11336 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
11338 len = TREE_VEC_LENGTH (purposevec);
11339 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
11341 else if (TREE_CODE (valuevec) == TREE_VEC)
11342 len = TREE_VEC_LENGTH (valuevec);
11345 /* Since we only performed a partial substitution into
11346 the argument pack, we only return a single list
11348 if (purposevec == TREE_PURPOSE (t)
11349 && valuevec == TREE_VALUE (t)
11350 && chain == TREE_CHAIN (t))
11353 return tree_cons (purposevec, valuevec, chain);
11356 /* Convert the argument vectors into a TREE_LIST */
11360 /* Grab the Ith values. */
11362 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
11365 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
11368 /* Build the list (backwards). */
11369 chain = tree_cons (purpose, value, chain);
11375 purpose = TREE_PURPOSE (t);
11377 purpose = RECUR (purpose);
11378 value = TREE_VALUE (t);
11380 value = RECUR (value);
11381 chain = TREE_CHAIN (t);
11382 if (chain && chain != void_type_node)
11383 chain = RECUR (chain);
11384 if (purpose == TREE_PURPOSE (t)
11385 && value == TREE_VALUE (t)
11386 && chain == TREE_CHAIN (t))
11388 return tree_cons (purpose, value, chain);
11391 case COMPONENT_REF:
11397 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11398 args, complain, in_decl);
11399 /* Remember that there was a reference to this entity. */
11400 if (DECL_P (object))
11401 mark_used (object);
11402 object_type = TREE_TYPE (object);
11404 member = TREE_OPERAND (t, 1);
11405 if (BASELINK_P (member))
11406 member = tsubst_baselink (member,
11407 non_reference (TREE_TYPE (object)),
11408 args, complain, in_decl);
11410 member = tsubst_copy (member, args, complain, in_decl);
11411 if (member == error_mark_node)
11412 return error_mark_node;
11414 if (object_type && !CLASS_TYPE_P (object_type))
11416 if (SCALAR_TYPE_P (object_type))
11418 tree s = NULL_TREE;
11419 tree dtor = member;
11421 if (TREE_CODE (dtor) == SCOPE_REF)
11423 s = TREE_OPERAND (dtor, 0);
11424 dtor = TREE_OPERAND (dtor, 1);
11426 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
11428 dtor = TREE_OPERAND (dtor, 0);
11430 return finish_pseudo_destructor_expr (object, s, dtor);
11434 else if (TREE_CODE (member) == SCOPE_REF
11435 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
11440 /* Lookup the template functions now that we know what the
11442 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
11443 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
11444 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
11445 /*is_type_p=*/false,
11446 /*complain=*/false);
11447 if (BASELINK_P (member))
11449 BASELINK_FUNCTIONS (member)
11450 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
11452 member = (adjust_result_of_qualified_name_lookup
11453 (member, BINFO_TYPE (BASELINK_BINFO (member)),
11458 qualified_name_lookup_error (object_type, tmpl, member,
11460 return error_mark_node;
11463 else if (TREE_CODE (member) == SCOPE_REF
11464 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
11465 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
11467 if (complain & tf_error)
11469 if (TYPE_P (TREE_OPERAND (member, 0)))
11470 error ("%qT is not a class or namespace",
11471 TREE_OPERAND (member, 0));
11473 error ("%qD is not a class or namespace",
11474 TREE_OPERAND (member, 0));
11476 return error_mark_node;
11478 else if (TREE_CODE (member) == FIELD_DECL)
11479 return finish_non_static_data_member (member, object, NULL_TREE);
11481 return finish_class_member_access_expr (object, member,
11482 /*template_p=*/false,
11488 (RECUR (TREE_OPERAND (t, 0)));
11492 VEC(constructor_elt,gc) *n;
11493 constructor_elt *ce;
11494 unsigned HOST_WIDE_INT idx;
11495 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11496 bool process_index_p;
11498 bool need_copy_p = false;
11501 if (type == error_mark_node)
11502 return error_mark_node;
11504 /* digest_init will do the wrong thing if we let it. */
11505 if (type && TYPE_PTRMEMFUNC_P (type))
11508 /* We do not want to process the index of aggregate
11509 initializers as they are identifier nodes which will be
11510 looked up by digest_init. */
11511 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
11513 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
11514 newlen = VEC_length (constructor_elt, n);
11515 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
11517 if (ce->index && process_index_p)
11518 ce->index = RECUR (ce->index);
11520 if (PACK_EXPANSION_P (ce->value))
11522 /* Substitute into the pack expansion. */
11523 ce->value = tsubst_pack_expansion (ce->value, args, complain,
11526 if (ce->value == error_mark_node)
11528 else if (TREE_VEC_LENGTH (ce->value) == 1)
11529 /* Just move the argument into place. */
11530 ce->value = TREE_VEC_ELT (ce->value, 0);
11533 /* Update the length of the final CONSTRUCTOR
11534 arguments vector, and note that we will need to
11536 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
11537 need_copy_p = true;
11541 ce->value = RECUR (ce->value);
11546 VEC(constructor_elt,gc) *old_n = n;
11548 n = VEC_alloc (constructor_elt, gc, newlen);
11549 for (idx = 0; VEC_iterate (constructor_elt, old_n, idx, ce);
11552 if (TREE_CODE (ce->value) == TREE_VEC)
11554 int i, len = TREE_VEC_LENGTH (ce->value);
11555 for (i = 0; i < len; ++i)
11556 CONSTRUCTOR_APPEND_ELT (n, 0,
11557 TREE_VEC_ELT (ce->value, i));
11560 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
11564 r = build_constructor (init_list_type_node, n);
11566 if (TREE_HAS_CONSTRUCTOR (t))
11567 return finish_compound_literal (type, r);
11574 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
11575 if (TYPE_P (operand_0))
11576 return get_typeid (operand_0);
11577 return build_typeid (operand_0);
11587 tree r = tsubst_copy (t, args, complain, in_decl);
11589 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
11590 /* If the original type was a reference, we'll be wrapped in
11591 the appropriate INDIRECT_REF. */
11592 r = convert_from_reference (r);
11597 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
11598 tsubst_copy (TREE_TYPE (t), args, complain,
11601 case OFFSETOF_EXPR:
11602 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
11606 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
11607 complain, in_decl);
11609 tree type2 = TRAIT_EXPR_TYPE2 (t);
11611 type2 = tsubst_copy (type2, args, complain, in_decl);
11613 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
11618 tree old_stmt_expr = cur_stmt_expr;
11619 tree stmt_expr = begin_stmt_expr ();
11621 cur_stmt_expr = stmt_expr;
11622 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
11623 integral_constant_expression_p);
11624 stmt_expr = finish_stmt_expr (stmt_expr, false);
11625 cur_stmt_expr = old_stmt_expr;
11631 t = tsubst_copy (t, args, complain, in_decl);
11632 /* As in finish_id_expression, we resolve enumeration constants
11633 to their underlying values. */
11634 if (TREE_CODE (t) == CONST_DECL)
11636 used_types_insert (TREE_TYPE (t));
11637 return DECL_INITIAL (t);
11642 /* Handle Objective-C++ constructs, if appropriate. */
11645 = objcp_tsubst_copy_and_build (t, args, complain,
11646 in_decl, /*function_p=*/false);
11650 return tsubst_copy (t, args, complain, in_decl);
11656 /* Verify that the instantiated ARGS are valid. For type arguments,
11657 make sure that the type's linkage is ok. For non-type arguments,
11658 make sure they are constants if they are integral or enumerations.
11659 Emit an error under control of COMPLAIN, and return TRUE on error. */
11662 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
11664 int ix, len = DECL_NTPARMS (tmpl);
11665 bool result = false;
11667 for (ix = 0; ix != len; ix++)
11669 tree t = TREE_VEC_ELT (args, ix);
11673 /* [basic.link]: A name with no linkage (notably, the name
11674 of a class or enumeration declared in a local scope)
11675 shall not be used to declare an entity with linkage.
11676 This implies that names with no linkage cannot be used as
11677 template arguments. */
11678 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
11682 /* DR 488 makes use of a type with no linkage cause
11683 type deduction to fail. */
11684 if (complain & tf_error)
11686 if (TYPE_ANONYMOUS_P (nt))
11687 error ("%qT is/uses anonymous type", t);
11689 error ("template argument for %qD uses local type %qT",
11694 /* In order to avoid all sorts of complications, we do not
11695 allow variably-modified types as template arguments. */
11696 else if (variably_modified_type_p (t, NULL_TREE))
11698 if (complain & tf_error)
11699 error ("%qT is a variably modified type", t);
11703 /* A non-type argument of integral or enumerated type must be a
11705 else if (TREE_TYPE (t)
11706 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
11707 && !TREE_CONSTANT (t))
11709 if (complain & tf_error)
11710 error ("integral expression %qE is not constant", t);
11714 if (result && (complain & tf_error))
11715 error (" trying to instantiate %qD", tmpl);
11719 /* Instantiate the indicated variable or function template TMPL with
11720 the template arguments in TARG_PTR. */
11723 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
11728 HOST_WIDE_INT saved_processing_template_decl;
11730 if (tmpl == error_mark_node)
11731 return error_mark_node;
11733 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
11735 /* If this function is a clone, handle it specially. */
11736 if (DECL_CLONED_FUNCTION_P (tmpl))
11741 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
11743 if (spec == error_mark_node)
11744 return error_mark_node;
11746 /* Look for the clone. */
11747 FOR_EACH_CLONE (clone, spec)
11748 if (DECL_NAME (clone) == DECL_NAME (tmpl))
11750 /* We should always have found the clone by now. */
11751 gcc_unreachable ();
11755 /* Check to see if we already have this specialization. */
11756 spec = retrieve_specialization (tmpl, targ_ptr,
11757 /*class_specializations_p=*/false);
11758 if (spec != NULL_TREE)
11761 gen_tmpl = most_general_template (tmpl);
11762 if (tmpl != gen_tmpl)
11764 /* The TMPL is a partial instantiation. To get a full set of
11765 arguments we must add the arguments used to perform the
11766 partial instantiation. */
11767 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
11770 /* Check to see if we already have this specialization. */
11771 spec = retrieve_specialization (gen_tmpl, targ_ptr,
11772 /*class_specializations_p=*/false);
11773 if (spec != NULL_TREE)
11777 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
11779 return error_mark_node;
11781 /* We are building a FUNCTION_DECL, during which the access of its
11782 parameters and return types have to be checked. However this
11783 FUNCTION_DECL which is the desired context for access checking
11784 is not built yet. We solve this chicken-and-egg problem by
11785 deferring all checks until we have the FUNCTION_DECL. */
11786 push_deferring_access_checks (dk_deferred);
11788 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
11789 (because, for example, we have encountered a non-dependent
11790 function call in the body of a template function and must now
11791 determine which of several overloaded functions will be called),
11792 within the instantiation itself we are not processing a
11794 saved_processing_template_decl = processing_template_decl;
11795 processing_template_decl = 0;
11796 /* Substitute template parameters to obtain the specialization. */
11797 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
11798 targ_ptr, complain, gen_tmpl);
11799 processing_template_decl = saved_processing_template_decl;
11800 if (fndecl == error_mark_node)
11801 return error_mark_node;
11803 /* Now we know the specialization, compute access previously
11805 push_access_scope (fndecl);
11806 perform_deferred_access_checks ();
11807 pop_access_scope (fndecl);
11808 pop_deferring_access_checks ();
11810 /* The DECL_TI_TEMPLATE should always be the immediate parent
11811 template, not the most general template. */
11812 DECL_TI_TEMPLATE (fndecl) = tmpl;
11814 /* If we've just instantiated the main entry point for a function,
11815 instantiate all the alternate entry points as well. We do this
11816 by cloning the instantiation of the main entry point, not by
11817 instantiating the template clones. */
11818 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
11819 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
11824 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
11825 arguments that are being used when calling it. TARGS is a vector
11826 into which the deduced template arguments are placed.
11828 Return zero for success, 2 for an incomplete match that doesn't resolve
11829 all the types, and 1 for complete failure. An error message will be
11830 printed only for an incomplete match.
11832 If FN is a conversion operator, or we are trying to produce a specific
11833 specialization, RETURN_TYPE is the return type desired.
11835 The EXPLICIT_TARGS are explicit template arguments provided via a
11838 The parameter STRICT is one of:
11841 We are deducing arguments for a function call, as in
11842 [temp.deduct.call].
11845 We are deducing arguments for a conversion function, as in
11846 [temp.deduct.conv].
11849 We are deducing arguments when doing an explicit instantiation
11850 as in [temp.explicit], when determining an explicit specialization
11851 as in [temp.expl.spec], or when taking the address of a function
11852 template, as in [temp.deduct.funcaddr]. */
11855 fn_type_unification (tree fn,
11856 tree explicit_targs,
11860 unification_kind_t strict,
11866 bool incomplete_argument_packs_p = false;
11868 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
11870 fntype = TREE_TYPE (fn);
11871 if (explicit_targs)
11875 The specified template arguments must match the template
11876 parameters in kind (i.e., type, nontype, template), and there
11877 must not be more arguments than there are parameters;
11878 otherwise type deduction fails.
11880 Nontype arguments must match the types of the corresponding
11881 nontype template parameters, or must be convertible to the
11882 types of the corresponding nontype parameters as specified in
11883 _temp.arg.nontype_, otherwise type deduction fails.
11885 All references in the function type of the function template
11886 to the corresponding template parameters are replaced by the
11887 specified template argument values. If a substitution in a
11888 template parameter or in the function type of the function
11889 template results in an invalid type, type deduction fails. */
11890 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
11891 int i, len = TREE_VEC_LENGTH (tparms);
11892 tree converted_args;
11893 bool incomplete = false;
11895 if (explicit_targs == error_mark_node)
11899 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
11900 /*require_all_args=*/false,
11901 /*use_default_args=*/false));
11902 if (converted_args == error_mark_node)
11905 /* Substitute the explicit args into the function type. This is
11906 necessary so that, for instance, explicitly declared function
11907 arguments can match null pointed constants. If we were given
11908 an incomplete set of explicit args, we must not do semantic
11909 processing during substitution as we could create partial
11911 for (i = 0; i < len; i++)
11913 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
11914 bool parameter_pack = false;
11916 /* Dig out the actual parm. */
11917 if (TREE_CODE (parm) == TYPE_DECL
11918 || TREE_CODE (parm) == TEMPLATE_DECL)
11920 parm = TREE_TYPE (parm);
11921 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
11923 else if (TREE_CODE (parm) == PARM_DECL)
11925 parm = DECL_INITIAL (parm);
11926 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
11929 if (parameter_pack)
11933 template_parm_level_and_index (parm, &level, &idx);
11935 /* Mark the argument pack as "incomplete". We could
11936 still deduce more arguments during unification. */
11937 targ = TMPL_ARG (converted_args, level, idx);
11940 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
11941 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
11942 = ARGUMENT_PACK_ARGS (targ);
11945 /* We have some incomplete argument packs. */
11946 incomplete_argument_packs_p = true;
11950 if (incomplete_argument_packs_p)
11951 /* Any substitution is guaranteed to be incomplete if there
11952 are incomplete argument packs, because we can still deduce
11956 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
11958 processing_template_decl += incomplete;
11959 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
11960 processing_template_decl -= incomplete;
11962 if (fntype == error_mark_node)
11965 /* Place the explicitly specified arguments in TARGS. */
11966 for (i = NUM_TMPL_ARGS (converted_args); i--;)
11967 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
11970 /* Never do unification on the 'this' parameter. */
11971 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
11975 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
11976 args = tree_cons (NULL_TREE, return_type, args);
11979 /* We allow incomplete unification without an error message here
11980 because the standard doesn't seem to explicitly prohibit it. Our
11981 callers must be ready to deal with unification failures in any
11983 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
11984 targs, parms, args, /*subr=*/0,
11987 if (result == 0 && incomplete_argument_packs_p)
11989 int i, len = NUM_TMPL_ARGS (targs);
11991 /* Clear the "incomplete" flags on all argument packs. */
11992 for (i = 0; i < len; i++)
11994 tree arg = TREE_VEC_ELT (targs, i);
11995 if (ARGUMENT_PACK_P (arg))
11997 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
11998 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
12003 /* Now that we have bindings for all of the template arguments,
12004 ensure that the arguments deduced for the template template
12005 parameters have compatible template parameter lists. We cannot
12006 check this property before we have deduced all template
12007 arguments, because the template parameter types of a template
12008 template parameter might depend on prior template parameters
12009 deduced after the template template parameter. The following
12010 ill-formed example illustrates this issue:
12012 template<typename T, template<T> class C> void f(C<5>, T);
12014 template<int N> struct X {};
12017 f(X<5>(), 5l); // error: template argument deduction fails
12020 The template parameter list of 'C' depends on the template type
12021 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
12022 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
12023 time that we deduce 'C'. */
12025 && !template_template_parm_bindings_ok_p
12026 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
12030 /* All is well so far. Now, check:
12034 When all template arguments have been deduced, all uses of
12035 template parameters in nondeduced contexts are replaced with
12036 the corresponding deduced argument values. If the
12037 substitution results in an invalid type, as described above,
12038 type deduction fails. */
12039 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
12040 == error_mark_node)
12046 /* Adjust types before performing type deduction, as described in
12047 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
12048 sections are symmetric. PARM is the type of a function parameter
12049 or the return type of the conversion function. ARG is the type of
12050 the argument passed to the call, or the type of the value
12051 initialized with the result of the conversion function.
12052 ARG_EXPR is the original argument expression, which may be null. */
12055 maybe_adjust_types_for_deduction (unification_kind_t strict,
12069 /* Swap PARM and ARG throughout the remainder of this
12070 function; the handling is precisely symmetric since PARM
12071 will initialize ARG rather than vice versa. */
12079 /* There is nothing to do in this case. */
12083 gcc_unreachable ();
12086 if (TREE_CODE (*parm) != REFERENCE_TYPE)
12088 /* [temp.deduct.call]
12090 If P is not a reference type:
12092 --If A is an array type, the pointer type produced by the
12093 array-to-pointer standard conversion (_conv.array_) is
12094 used in place of A for type deduction; otherwise,
12096 --If A is a function type, the pointer type produced by
12097 the function-to-pointer standard conversion
12098 (_conv.func_) is used in place of A for type deduction;
12101 --If A is a cv-qualified type, the top level
12102 cv-qualifiers of A's type are ignored for type
12104 if (TREE_CODE (*arg) == ARRAY_TYPE)
12105 *arg = build_pointer_type (TREE_TYPE (*arg));
12106 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
12107 *arg = build_pointer_type (*arg);
12109 *arg = TYPE_MAIN_VARIANT (*arg);
12112 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
12113 of the form T&&, where T is a template parameter, and the argument
12114 is an lvalue, T is deduced as A& */
12115 if (TREE_CODE (*parm) == REFERENCE_TYPE
12116 && TYPE_REF_IS_RVALUE (*parm)
12117 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
12118 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
12119 && arg_expr && real_lvalue_p (arg_expr))
12120 *arg = build_reference_type (*arg);
12122 /* [temp.deduct.call]
12124 If P is a cv-qualified type, the top level cv-qualifiers
12125 of P's type are ignored for type deduction. If P is a
12126 reference type, the type referred to by P is used for
12128 *parm = TYPE_MAIN_VARIANT (*parm);
12129 if (TREE_CODE (*parm) == REFERENCE_TYPE)
12131 *parm = TREE_TYPE (*parm);
12132 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
12135 /* DR 322. For conversion deduction, remove a reference type on parm
12136 too (which has been swapped into ARG). */
12137 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
12138 *arg = TREE_TYPE (*arg);
12143 /* Most parms like fn_type_unification.
12145 If SUBR is 1, we're being called recursively (to unify the
12146 arguments of a function or method parameter of a function
12150 type_unification_real (tree tparms,
12155 unification_kind_t strict,
12158 tree parm, arg, arg_expr;
12160 int ntparms = TREE_VEC_LENGTH (tparms);
12162 int saw_undeduced = 0;
12165 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
12166 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
12167 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
12168 gcc_assert (ntparms > 0);
12173 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
12174 | UNIFY_ALLOW_DERIVED);
12178 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
12182 sub_strict = UNIFY_ALLOW_NONE;
12186 gcc_unreachable ();
12193 while (parms && parms != void_list_node
12194 && args && args != void_list_node)
12196 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
12199 parm = TREE_VALUE (parms);
12200 parms = TREE_CHAIN (parms);
12201 arg = TREE_VALUE (args);
12202 args = TREE_CHAIN (args);
12205 if (arg == error_mark_node)
12207 if (arg == unknown_type_node)
12208 /* We can't deduce anything from this, but we might get all the
12209 template args from other function args. */
12212 /* Conversions will be performed on a function argument that
12213 corresponds with a function parameter that contains only
12214 non-deducible template parameters and explicitly specified
12215 template parameters. */
12216 if (!uses_template_parms (parm))
12221 type = TREE_TYPE (arg);
12225 if (same_type_p (parm, type))
12227 if (strict != DEDUCE_EXACT
12228 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
12237 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
12238 if (type_unknown_p (arg))
12240 /* [temp.deduct.type]
12242 A template-argument can be deduced from a pointer to
12243 function or pointer to member function argument if
12244 the set of overloaded functions does not contain
12245 function templates and at most one of a set of
12246 overloaded functions provides a unique match. */
12247 if (resolve_overloaded_unification
12248 (tparms, targs, parm, arg, strict, sub_strict))
12254 arg = unlowered_expr_type (arg);
12255 if (arg == error_mark_node)
12260 int arg_strict = sub_strict;
12263 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
12266 if (arg == init_list_type_node && arg_expr)
12268 if (unify (tparms, targs, parm, arg, arg_strict))
12275 && parms != void_list_node
12276 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
12278 /* Unify the remaining arguments with the pack expansion type. */
12280 tree parmvec = make_tree_vec (1);
12284 /* Count the number of arguments that remain. */
12285 for (t = args; t && t != void_list_node; t = TREE_CHAIN (t))
12288 /* Allocate a TREE_VEC and copy in all of the arguments */
12289 argvec = make_tree_vec (len);
12290 for (i = 0; args && args != void_list_node; args = TREE_CHAIN (args))
12292 TREE_VEC_ELT (argvec, i) = TREE_VALUE (args);
12296 /* Copy the parameter into parmvec. */
12297 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
12298 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
12299 /*call_args_p=*/true, /*subr=*/subr))
12302 /* Advance to the end of the list of parameters. */
12303 parms = TREE_CHAIN (parms);
12306 /* Fail if we've reached the end of the parm list, and more args
12307 are present, and the parm list isn't variadic. */
12308 if (args && args != void_list_node && parms == void_list_node)
12310 /* Fail if parms are left and they don't have default values. */
12311 if (parms && parms != void_list_node
12312 && TREE_PURPOSE (parms) == NULL_TREE)
12316 for (i = 0; i < ntparms; i++)
12317 if (!TREE_VEC_ELT (targs, i))
12321 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
12324 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
12326 /* If this is an undeduced nontype parameter that depends on
12327 a type parameter, try another pass; its type may have been
12328 deduced from a later argument than the one from which
12329 this parameter can be deduced. */
12330 if (TREE_CODE (tparm) == PARM_DECL
12331 && uses_template_parms (TREE_TYPE (tparm))
12332 && !saw_undeduced++)
12335 /* Core issue #226 (C++0x) [temp.deduct]:
12337 If a template argument has not been deduced, its
12338 default template argument, if any, is used.
12340 When we are in C++98 mode, TREE_PURPOSE will either
12341 be NULL_TREE or ERROR_MARK_NODE, so we do not need
12342 to explicitly check cxx_dialect here. */
12343 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
12345 tree arg = tsubst (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)),
12346 targs, tf_none, NULL_TREE);
12347 if (arg == error_mark_node)
12351 TREE_VEC_ELT (targs, i) = arg;
12356 /* If the type parameter is a parameter pack, then it will
12357 be deduced to an empty parameter pack. */
12358 if (template_parameter_pack_p (tparm))
12362 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
12364 arg = make_node (NONTYPE_ARGUMENT_PACK);
12365 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
12366 TREE_CONSTANT (arg) = 1;
12369 arg = make_node (TYPE_ARGUMENT_PACK);
12371 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
12373 TREE_VEC_ELT (targs, i) = arg;
12383 /* Subroutine of type_unification_real. Args are like the variables
12384 at the call site. ARG is an overloaded function (or template-id);
12385 we try deducing template args from each of the overloads, and if
12386 only one succeeds, we go with that. Modifies TARGS and returns
12387 true on success. */
12390 resolve_overloaded_unification (tree tparms,
12394 unification_kind_t strict,
12397 tree tempargs = copy_node (targs);
12401 if (TREE_CODE (arg) == ADDR_EXPR)
12403 arg = TREE_OPERAND (arg, 0);
12409 if (TREE_CODE (arg) == COMPONENT_REF)
12410 /* Handle `&x' where `x' is some static or non-static member
12412 arg = TREE_OPERAND (arg, 1);
12414 if (TREE_CODE (arg) == OFFSET_REF)
12415 arg = TREE_OPERAND (arg, 1);
12417 /* Strip baselink information. */
12418 if (BASELINK_P (arg))
12419 arg = BASELINK_FUNCTIONS (arg);
12421 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
12423 /* If we got some explicit template args, we need to plug them into
12424 the affected templates before we try to unify, in case the
12425 explicit args will completely resolve the templates in question. */
12427 tree expl_subargs = TREE_OPERAND (arg, 1);
12428 arg = TREE_OPERAND (arg, 0);
12430 for (; arg; arg = OVL_NEXT (arg))
12432 tree fn = OVL_CURRENT (arg);
12433 tree subargs, elem;
12435 if (TREE_CODE (fn) != TEMPLATE_DECL)
12438 ++processing_template_decl;
12439 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
12440 expl_subargs, /*check_ret=*/false);
12443 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
12444 good += try_one_overload (tparms, targs, tempargs, parm,
12445 elem, strict, sub_strict, addr_p);
12447 --processing_template_decl;
12450 else if (TREE_CODE (arg) != OVERLOAD
12451 && TREE_CODE (arg) != FUNCTION_DECL)
12452 /* If ARG is, for example, "(0, &f)" then its type will be unknown
12453 -- but the deduction does not succeed because the expression is
12454 not just the function on its own. */
12457 for (; arg; arg = OVL_NEXT (arg))
12458 good += try_one_overload (tparms, targs, tempargs, parm,
12459 TREE_TYPE (OVL_CURRENT (arg)),
12460 strict, sub_strict, addr_p);
12462 /* [temp.deduct.type] A template-argument can be deduced from a pointer
12463 to function or pointer to member function argument if the set of
12464 overloaded functions does not contain function templates and at most
12465 one of a set of overloaded functions provides a unique match.
12467 So if we found multiple possibilities, we return success but don't
12468 deduce anything. */
12472 int i = TREE_VEC_LENGTH (targs);
12474 if (TREE_VEC_ELT (tempargs, i))
12475 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
12483 /* Subroutine of resolve_overloaded_unification; does deduction for a single
12484 overload. Fills TARGS with any deduced arguments, or error_mark_node if
12485 different overloads deduce different arguments for a given parm.
12486 ADDR_P is true if the expression for which deduction is being
12487 performed was of the form "& fn" rather than simply "fn".
12489 Returns 1 on success. */
12492 try_one_overload (tree tparms,
12497 unification_kind_t strict,
12505 /* [temp.deduct.type] A template-argument can be deduced from a pointer
12506 to function or pointer to member function argument if the set of
12507 overloaded functions does not contain function templates and at most
12508 one of a set of overloaded functions provides a unique match.
12510 So if this is a template, just return success. */
12512 if (uses_template_parms (arg))
12515 if (TREE_CODE (arg) == METHOD_TYPE)
12516 arg = build_ptrmemfunc_type (build_pointer_type (arg));
12518 arg = build_pointer_type (arg);
12520 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
12522 /* We don't copy orig_targs for this because if we have already deduced
12523 some template args from previous args, unify would complain when we
12524 try to deduce a template parameter for the same argument, even though
12525 there isn't really a conflict. */
12526 nargs = TREE_VEC_LENGTH (targs);
12527 tempargs = make_tree_vec (nargs);
12529 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
12532 /* First make sure we didn't deduce anything that conflicts with
12533 explicitly specified args. */
12534 for (i = nargs; i--; )
12536 tree elt = TREE_VEC_ELT (tempargs, i);
12537 tree oldelt = TREE_VEC_ELT (orig_targs, i);
12541 else if (uses_template_parms (elt))
12542 /* Since we're unifying against ourselves, we will fill in
12543 template args used in the function parm list with our own
12544 template parms. Discard them. */
12545 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
12546 else if (oldelt && !template_args_equal (oldelt, elt))
12550 for (i = nargs; i--; )
12552 tree elt = TREE_VEC_ELT (tempargs, i);
12555 TREE_VEC_ELT (targs, i) = elt;
12561 /* PARM is a template class (perhaps with unbound template
12562 parameters). ARG is a fully instantiated type. If ARG can be
12563 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
12564 TARGS are as for unify. */
12567 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
12569 tree copy_of_targs;
12571 if (!CLASSTYPE_TEMPLATE_INFO (arg)
12572 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
12573 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
12576 /* We need to make a new template argument vector for the call to
12577 unify. If we used TARGS, we'd clutter it up with the result of
12578 the attempted unification, even if this class didn't work out.
12579 We also don't want to commit ourselves to all the unifications
12580 we've already done, since unification is supposed to be done on
12581 an argument-by-argument basis. In other words, consider the
12582 following pathological case:
12584 template <int I, int J, int K>
12587 template <int I, int J>
12588 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
12590 template <int I, int J, int K>
12591 void f(S<I, J, K>, S<I, I, I>);
12600 Now, by the time we consider the unification involving `s2', we
12601 already know that we must have `f<0, 0, 0>'. But, even though
12602 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
12603 because there are two ways to unify base classes of S<0, 1, 2>
12604 with S<I, I, I>. If we kept the already deduced knowledge, we
12605 would reject the possibility I=1. */
12606 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
12608 /* If unification failed, we're done. */
12609 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
12610 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
12616 /* Given a template type PARM and a class type ARG, find the unique
12617 base type in ARG that is an instance of PARM. We do not examine
12618 ARG itself; only its base-classes. If there is not exactly one
12619 appropriate base class, return NULL_TREE. PARM may be the type of
12620 a partial specialization, as well as a plain template type. Used
12624 get_template_base (tree tparms, tree targs, tree parm, tree arg)
12626 tree rval = NULL_TREE;
12629 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
12631 binfo = TYPE_BINFO (complete_type (arg));
12633 /* The type could not be completed. */
12636 /* Walk in inheritance graph order. The search order is not
12637 important, and this avoids multiple walks of virtual bases. */
12638 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
12640 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
12644 /* If there is more than one satisfactory baseclass, then:
12648 If they yield more than one possible deduced A, the type
12652 if (rval && !same_type_p (r, rval))
12662 /* Returns the level of DECL, which declares a template parameter. */
12665 template_decl_level (tree decl)
12667 switch (TREE_CODE (decl))
12670 case TEMPLATE_DECL:
12671 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
12674 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
12677 gcc_unreachable ();
12682 /* Decide whether ARG can be unified with PARM, considering only the
12683 cv-qualifiers of each type, given STRICT as documented for unify.
12684 Returns nonzero iff the unification is OK on that basis. */
12687 check_cv_quals_for_unify (int strict, tree arg, tree parm)
12689 int arg_quals = cp_type_quals (arg);
12690 int parm_quals = cp_type_quals (parm);
12692 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
12693 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
12695 /* Although a CVR qualifier is ignored when being applied to a
12696 substituted template parameter ([8.3.2]/1 for example), that
12697 does not apply during deduction [14.8.2.4]/1, (even though
12698 that is not explicitly mentioned, [14.8.2.4]/9 indicates
12699 this). Except when we're allowing additional CV qualifiers
12700 at the outer level [14.8.2.1]/3,1st bullet. */
12701 if ((TREE_CODE (arg) == REFERENCE_TYPE
12702 || TREE_CODE (arg) == FUNCTION_TYPE
12703 || TREE_CODE (arg) == METHOD_TYPE)
12704 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
12707 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
12708 && (parm_quals & TYPE_QUAL_RESTRICT))
12712 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
12713 && (arg_quals & parm_quals) != parm_quals)
12716 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
12717 && (parm_quals & arg_quals) != arg_quals)
12723 /* Determines the LEVEL and INDEX for the template parameter PARM. */
12725 template_parm_level_and_index (tree parm, int* level, int* index)
12727 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
12728 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
12729 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
12731 *index = TEMPLATE_TYPE_IDX (parm);
12732 *level = TEMPLATE_TYPE_LEVEL (parm);
12736 *index = TEMPLATE_PARM_IDX (parm);
12737 *level = TEMPLATE_PARM_LEVEL (parm);
12741 /* Unifies the remaining arguments in PACKED_ARGS with the pack
12742 expansion at the end of PACKED_PARMS. Returns 0 if the type
12743 deduction succeeds, 1 otherwise. STRICT is the same as in
12744 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
12745 call argument list. We'll need to adjust the arguments to make them
12746 types. SUBR tells us if this is from a recursive call to
12747 type_unification_real. */
12749 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
12750 tree packed_args, int strict, bool call_args_p,
12754 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
12755 tree pattern = PACK_EXPANSION_PATTERN (parm);
12756 tree pack, packs = NULL_TREE;
12757 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
12758 int len = TREE_VEC_LENGTH (packed_args);
12760 /* Determine the parameter packs we will be deducing from the
12761 pattern, and record their current deductions. */
12762 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
12763 pack; pack = TREE_CHAIN (pack))
12765 tree parm_pack = TREE_VALUE (pack);
12768 /* Determine the index and level of this parameter pack. */
12769 template_parm_level_and_index (parm_pack, &level, &idx);
12771 /* Keep track of the parameter packs and their corresponding
12773 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
12774 TREE_TYPE (packs) = make_tree_vec (len - start);
12777 /* Loop through all of the arguments that have not yet been
12778 unified and unify each with the pattern. */
12779 for (i = start; i < len; i++)
12781 tree parm = pattern;
12783 /* For each parameter pack, clear out the deduced value so that
12784 we can deduce it again. */
12785 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12788 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12790 TMPL_ARG (targs, level, idx) = NULL_TREE;
12793 /* Unify the pattern with the current argument. */
12795 tree arg = TREE_VEC_ELT (packed_args, i);
12796 tree arg_expr = NULL_TREE;
12797 int arg_strict = strict;
12798 bool skip_arg_p = false;
12804 /* This mirrors what we do in type_unification_real. */
12808 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
12809 | UNIFY_ALLOW_MORE_CV_QUAL
12810 | UNIFY_ALLOW_DERIVED);
12814 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
12818 sub_strict = UNIFY_ALLOW_NONE;
12822 gcc_unreachable ();
12827 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
12828 if (type_unknown_p (arg))
12830 /* [temp.deduct.type] A template-argument can be
12831 deduced from a pointer to function or pointer
12832 to member function argument if the set of
12833 overloaded functions does not contain function
12834 templates and at most one of a set of
12835 overloaded functions provides a unique
12838 if (resolve_overloaded_unification
12839 (tparms, targs, parm, arg, strict, sub_strict)
12848 arg = unlowered_expr_type (arg);
12849 if (arg == error_mark_node)
12854 arg_strict = sub_strict;
12858 maybe_adjust_types_for_deduction (strict, &parm, &arg,
12864 if (unify (tparms, targs, parm, arg, arg_strict))
12869 /* For each parameter pack, collect the deduced value. */
12870 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12873 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12875 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
12876 TMPL_ARG (targs, level, idx);
12880 /* Verify that the results of unification with the parameter packs
12881 produce results consistent with what we've seen before, and make
12882 the deduced argument packs available. */
12883 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12885 tree old_pack = TREE_VALUE (pack);
12886 tree new_args = TREE_TYPE (pack);
12887 int i, len = TREE_VEC_LENGTH (new_args);
12888 bool nondeduced_p = false;
12890 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
12891 actually deduce anything. */
12892 for (i = 0; i < len && !nondeduced_p; ++i)
12893 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
12894 nondeduced_p = true;
12898 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
12900 /* Prepend the explicit arguments onto NEW_ARGS. */
12901 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
12902 tree old_args = new_args;
12903 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
12904 int len = explicit_len + TREE_VEC_LENGTH (old_args);
12906 /* Copy the explicit arguments. */
12907 new_args = make_tree_vec (len);
12908 for (i = 0; i < explicit_len; i++)
12909 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
12911 /* Copy the deduced arguments. */
12912 for (; i < len; i++)
12913 TREE_VEC_ELT (new_args, i) =
12914 TREE_VEC_ELT (old_args, i - explicit_len);
12922 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12924 /* Build the deduced *_ARGUMENT_PACK. */
12925 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
12927 result = make_node (NONTYPE_ARGUMENT_PACK);
12928 TREE_TYPE (result) =
12929 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
12930 TREE_CONSTANT (result) = 1;
12933 result = make_node (TYPE_ARGUMENT_PACK);
12935 SET_ARGUMENT_PACK_ARGS (result, new_args);
12937 /* Note the deduced argument packs for this parameter
12939 TMPL_ARG (targs, level, idx) = result;
12941 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
12942 && (ARGUMENT_PACK_ARGS (old_pack)
12943 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
12945 /* We only had the explicitly-provided arguments before, but
12946 now we have a complete set of arguments. */
12948 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
12949 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12951 /* Keep the original deduced argument pack. */
12952 TMPL_ARG (targs, level, idx) = old_pack;
12954 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
12955 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
12956 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
12958 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
12960 /* Inconsistent unification of this parameter pack. */
12966 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12968 /* Keep the original deduced argument pack. */
12969 TMPL_ARG (targs, level, idx) = old_pack;
12976 /* Deduce the value of template parameters. TPARMS is the (innermost)
12977 set of template parameters to a template. TARGS is the bindings
12978 for those template parameters, as determined thus far; TARGS may
12979 include template arguments for outer levels of template parameters
12980 as well. PARM is a parameter to a template function, or a
12981 subcomponent of that parameter; ARG is the corresponding argument.
12982 This function attempts to match PARM with ARG in a manner
12983 consistent with the existing assignments in TARGS. If more values
12984 are deduced, then TARGS is updated.
12986 Returns 0 if the type deduction succeeds, 1 otherwise. The
12987 parameter STRICT is a bitwise or of the following flags:
12990 Require an exact match between PARM and ARG.
12991 UNIFY_ALLOW_MORE_CV_QUAL:
12992 Allow the deduced ARG to be more cv-qualified (by qualification
12993 conversion) than ARG.
12994 UNIFY_ALLOW_LESS_CV_QUAL:
12995 Allow the deduced ARG to be less cv-qualified than ARG.
12996 UNIFY_ALLOW_DERIVED:
12997 Allow the deduced ARG to be a template base class of ARG,
12998 or a pointer to a template base class of the type pointed to by
13000 UNIFY_ALLOW_INTEGER:
13001 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
13002 case for more information.
13003 UNIFY_ALLOW_OUTER_LEVEL:
13004 This is the outermost level of a deduction. Used to determine validity
13005 of qualification conversions. A valid qualification conversion must
13006 have const qualified pointers leading up to the inner type which
13007 requires additional CV quals, except at the outer level, where const
13008 is not required [conv.qual]. It would be normal to set this flag in
13009 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
13010 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
13011 This is the outermost level of a deduction, and PARM can be more CV
13012 qualified at this point.
13013 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
13014 This is the outermost level of a deduction, and PARM can be less CV
13015 qualified at this point. */
13018 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
13023 int strict_in = strict;
13025 /* I don't think this will do the right thing with respect to types.
13026 But the only case I've seen it in so far has been array bounds, where
13027 signedness is the only information lost, and I think that will be
13029 while (TREE_CODE (parm) == NOP_EXPR)
13030 parm = TREE_OPERAND (parm, 0);
13032 if (arg == error_mark_node)
13034 if (arg == unknown_type_node
13035 || arg == init_list_type_node)
13036 /* We can't deduce anything from this, but we might get all the
13037 template args from other function args. */
13040 /* If PARM uses template parameters, then we can't bail out here,
13041 even if ARG == PARM, since we won't record unifications for the
13042 template parameters. We might need them if we're trying to
13043 figure out which of two things is more specialized. */
13044 if (arg == parm && !uses_template_parms (parm))
13047 /* Handle init lists early, so the rest of the function can assume
13048 we're dealing with a type. */
13049 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
13054 if (!is_std_init_list (parm))
13055 /* We can only deduce from an initializer list argument if the
13056 parameter is std::initializer_list; otherwise this is a
13057 non-deduced context. */
13060 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
13062 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
13064 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
13065 elt = TREE_TYPE (elt);
13066 if (unify (tparms, targs, elttype, elt, UNIFY_ALLOW_NONE))
13072 /* Immediately reject some pairs that won't unify because of
13073 cv-qualification mismatches. */
13074 if (TREE_CODE (arg) == TREE_CODE (parm)
13076 /* It is the elements of the array which hold the cv quals of an array
13077 type, and the elements might be template type parms. We'll check
13078 when we recurse. */
13079 && TREE_CODE (arg) != ARRAY_TYPE
13080 /* We check the cv-qualifiers when unifying with template type
13081 parameters below. We want to allow ARG `const T' to unify with
13082 PARM `T' for example, when computing which of two templates
13083 is more specialized, for example. */
13084 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
13085 && !check_cv_quals_for_unify (strict_in, arg, parm))
13088 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
13089 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
13090 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
13091 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
13092 strict &= ~UNIFY_ALLOW_DERIVED;
13093 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
13094 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
13096 switch (TREE_CODE (parm))
13098 case TYPENAME_TYPE:
13100 case UNBOUND_CLASS_TEMPLATE:
13101 /* In a type which contains a nested-name-specifier, template
13102 argument values cannot be deduced for template parameters used
13103 within the nested-name-specifier. */
13106 case TEMPLATE_TYPE_PARM:
13107 case TEMPLATE_TEMPLATE_PARM:
13108 case BOUND_TEMPLATE_TEMPLATE_PARM:
13109 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
13110 if (tparm == error_mark_node)
13113 if (TEMPLATE_TYPE_LEVEL (parm)
13114 != template_decl_level (tparm))
13115 /* The PARM is not one we're trying to unify. Just check
13116 to see if it matches ARG. */
13117 return (TREE_CODE (arg) == TREE_CODE (parm)
13118 && same_type_p (parm, arg)) ? 0 : 1;
13119 idx = TEMPLATE_TYPE_IDX (parm);
13120 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
13121 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
13123 /* Check for mixed types and values. */
13124 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13125 && TREE_CODE (tparm) != TYPE_DECL)
13126 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13127 && TREE_CODE (tparm) != TEMPLATE_DECL))
13130 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13132 /* ARG must be constructed from a template class or a template
13133 template parameter. */
13134 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
13135 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
13139 tree parmvec = TYPE_TI_ARGS (parm);
13140 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
13142 = DECL_INNERMOST_TEMPLATE_PARMS
13143 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
13145 int parm_variadic_p = 0;
13147 /* The resolution to DR150 makes clear that default
13148 arguments for an N-argument may not be used to bind T
13149 to a template template parameter with fewer than N
13150 parameters. It is not safe to permit the binding of
13151 default arguments as an extension, as that may change
13152 the meaning of a conforming program. Consider:
13154 struct Dense { static const unsigned int dim = 1; };
13156 template <template <typename> class View,
13158 void operator+(float, View<Block> const&);
13160 template <typename Block,
13161 unsigned int Dim = Block::dim>
13162 struct Lvalue_proxy { operator float() const; };
13166 Lvalue_proxy<Dense> p;
13171 Here, if Lvalue_proxy is permitted to bind to View, then
13172 the global operator+ will be used; if they are not, the
13173 Lvalue_proxy will be converted to float. */
13174 if (coerce_template_parms (parm_parms,
13176 TYPE_TI_TEMPLATE (parm),
13178 /*require_all_args=*/true,
13179 /*use_default_args=*/false)
13180 == error_mark_node)
13183 /* Deduce arguments T, i from TT<T> or TT<i>.
13184 We check each element of PARMVEC and ARGVEC individually
13185 rather than the whole TREE_VEC since they can have
13186 different number of elements. */
13188 parmvec = expand_template_argument_pack (parmvec);
13189 argvec = expand_template_argument_pack (argvec);
13191 len = TREE_VEC_LENGTH (parmvec);
13193 /* Check if the parameters end in a pack, making them
13196 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
13197 parm_variadic_p = 1;
13199 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
13202 for (i = 0; i < len - parm_variadic_p; ++i)
13204 if (unify (tparms, targs,
13205 TREE_VEC_ELT (parmvec, i),
13206 TREE_VEC_ELT (argvec, i),
13211 if (parm_variadic_p
13212 && unify_pack_expansion (tparms, targs,
13215 /*call_args_p=*/false,
13219 arg = TYPE_TI_TEMPLATE (arg);
13221 /* Fall through to deduce template name. */
13224 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13225 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13227 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
13229 /* Simple cases: Value already set, does match or doesn't. */
13230 if (targ != NULL_TREE && template_args_equal (targ, arg))
13237 /* If PARM is `const T' and ARG is only `int', we don't have
13238 a match unless we are allowing additional qualification.
13239 If ARG is `const int' and PARM is just `T' that's OK;
13240 that binds `const int' to `T'. */
13241 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
13245 /* Consider the case where ARG is `const volatile int' and
13246 PARM is `const T'. Then, T should be `volatile int'. */
13247 arg = cp_build_qualified_type_real
13248 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
13249 if (arg == error_mark_node)
13252 /* Simple cases: Value already set, does match or doesn't. */
13253 if (targ != NULL_TREE && same_type_p (targ, arg))
13258 /* Make sure that ARG is not a variable-sized array. (Note
13259 that were talking about variable-sized arrays (like
13260 `int[n]'), rather than arrays of unknown size (like
13261 `int[]').) We'll get very confused by such a type since
13262 the bound of the array will not be computable in an
13263 instantiation. Besides, such types are not allowed in
13264 ISO C++, so we can do as we please here. */
13265 if (variably_modified_type_p (arg, NULL_TREE))
13269 /* If ARG is a parameter pack or an expansion, we cannot unify
13270 against it unless PARM is also a parameter pack. */
13271 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
13272 && !template_parameter_pack_p (parm))
13275 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
13278 case TEMPLATE_PARM_INDEX:
13279 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
13280 if (tparm == error_mark_node)
13283 if (TEMPLATE_PARM_LEVEL (parm)
13284 != template_decl_level (tparm))
13285 /* The PARM is not one we're trying to unify. Just check
13286 to see if it matches ARG. */
13287 return !(TREE_CODE (arg) == TREE_CODE (parm)
13288 && cp_tree_equal (parm, arg));
13290 idx = TEMPLATE_PARM_IDX (parm);
13291 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
13294 return !cp_tree_equal (targ, arg);
13296 /* [temp.deduct.type] If, in the declaration of a function template
13297 with a non-type template-parameter, the non-type
13298 template-parameter is used in an expression in the function
13299 parameter-list and, if the corresponding template-argument is
13300 deduced, the template-argument type shall match the type of the
13301 template-parameter exactly, except that a template-argument
13302 deduced from an array bound may be of any integral type.
13303 The non-type parameter might use already deduced type parameters. */
13304 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
13305 if (!TREE_TYPE (arg))
13306 /* Template-parameter dependent expression. Just accept it for now.
13307 It will later be processed in convert_template_argument. */
13309 else if (same_type_p (TREE_TYPE (arg), tparm))
13311 else if ((strict & UNIFY_ALLOW_INTEGER)
13312 && (TREE_CODE (tparm) == INTEGER_TYPE
13313 || TREE_CODE (tparm) == BOOLEAN_TYPE))
13314 /* Convert the ARG to the type of PARM; the deduced non-type
13315 template argument must exactly match the types of the
13316 corresponding parameter. */
13317 arg = fold (build_nop (TREE_TYPE (parm), arg));
13318 else if (uses_template_parms (tparm))
13319 /* We haven't deduced the type of this parameter yet. Try again
13325 /* If ARG is a parameter pack or an expansion, we cannot unify
13326 against it unless PARM is also a parameter pack. */
13327 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
13328 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
13331 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
13336 /* A pointer-to-member constant can be unified only with
13337 another constant. */
13338 if (TREE_CODE (arg) != PTRMEM_CST)
13341 /* Just unify the class member. It would be useless (and possibly
13342 wrong, depending on the strict flags) to unify also
13343 PTRMEM_CST_CLASS, because we want to be sure that both parm and
13344 arg refer to the same variable, even if through different
13345 classes. For instance:
13347 struct A { int x; };
13350 Unification of &A::x and &B::x must succeed. */
13351 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
13352 PTRMEM_CST_MEMBER (arg), strict);
13357 if (TREE_CODE (arg) != POINTER_TYPE)
13360 /* [temp.deduct.call]
13362 A can be another pointer or pointer to member type that can
13363 be converted to the deduced A via a qualification
13364 conversion (_conv.qual_).
13366 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
13367 This will allow for additional cv-qualification of the
13368 pointed-to types if appropriate. */
13370 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
13371 /* The derived-to-base conversion only persists through one
13372 level of pointers. */
13373 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
13375 return unify (tparms, targs, TREE_TYPE (parm),
13376 TREE_TYPE (arg), strict);
13379 case REFERENCE_TYPE:
13380 if (TREE_CODE (arg) != REFERENCE_TYPE)
13382 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
13383 strict & UNIFY_ALLOW_MORE_CV_QUAL);
13386 if (TREE_CODE (arg) != ARRAY_TYPE)
13388 if ((TYPE_DOMAIN (parm) == NULL_TREE)
13389 != (TYPE_DOMAIN (arg) == NULL_TREE))
13391 if (TYPE_DOMAIN (parm) != NULL_TREE)
13398 /* Our representation of array types uses "N - 1" as the
13399 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
13400 not an integer constant. We cannot unify arbitrarily
13401 complex expressions, so we eliminate the MINUS_EXPRs
13403 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
13404 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
13407 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
13408 parm_max = TREE_OPERAND (parm_max, 0);
13410 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
13411 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
13414 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
13415 trying to unify the type of a variable with the type
13416 of a template parameter. For example:
13418 template <unsigned int N>
13419 void f (char (&) [N]);
13426 Here, the type of the ARG will be "int [g(i)]", and
13427 may be a SAVE_EXPR, etc. */
13428 if (TREE_CODE (arg_max) != MINUS_EXPR)
13430 arg_max = TREE_OPERAND (arg_max, 0);
13433 /* If only one of the bounds used a MINUS_EXPR, compensate
13434 by adding one to the other bound. */
13435 if (parm_cst && !arg_cst)
13436 parm_max = fold_build2 (PLUS_EXPR,
13440 else if (arg_cst && !parm_cst)
13441 arg_max = fold_build2 (PLUS_EXPR,
13446 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
13449 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
13450 strict & UNIFY_ALLOW_MORE_CV_QUAL);
13457 case ENUMERAL_TYPE:
13459 if (TREE_CODE (arg) != TREE_CODE (parm))
13462 /* We have already checked cv-qualification at the top of the
13464 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
13467 /* As far as unification is concerned, this wins. Later checks
13468 will invalidate it if necessary. */
13471 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
13472 /* Type INTEGER_CST can come from ordinary constant template args. */
13474 while (TREE_CODE (arg) == NOP_EXPR)
13475 arg = TREE_OPERAND (arg, 0);
13477 if (TREE_CODE (arg) != INTEGER_CST)
13479 return !tree_int_cst_equal (parm, arg);
13484 if (TREE_CODE (arg) != TREE_VEC)
13486 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
13488 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
13489 if (unify (tparms, targs,
13490 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
13498 if (TREE_CODE (arg) != TREE_CODE (parm))
13501 if (TYPE_PTRMEMFUNC_P (parm))
13503 if (!TYPE_PTRMEMFUNC_P (arg))
13506 return unify (tparms, targs,
13507 TYPE_PTRMEMFUNC_FN_TYPE (parm),
13508 TYPE_PTRMEMFUNC_FN_TYPE (arg),
13512 if (CLASSTYPE_TEMPLATE_INFO (parm))
13514 tree t = NULL_TREE;
13516 if (strict_in & UNIFY_ALLOW_DERIVED)
13518 /* First, we try to unify the PARM and ARG directly. */
13519 t = try_class_unification (tparms, targs,
13524 /* Fallback to the special case allowed in
13525 [temp.deduct.call]:
13527 If P is a class, and P has the form
13528 template-id, then A can be a derived class of
13529 the deduced A. Likewise, if P is a pointer to
13530 a class of the form template-id, A can be a
13531 pointer to a derived class pointed to by the
13533 t = get_template_base (tparms, targs, parm, arg);
13539 else if (CLASSTYPE_TEMPLATE_INFO (arg)
13540 && (CLASSTYPE_TI_TEMPLATE (parm)
13541 == CLASSTYPE_TI_TEMPLATE (arg)))
13542 /* Perhaps PARM is something like S<U> and ARG is S<int>.
13543 Then, we should unify `int' and `U'. */
13546 /* There's no chance of unification succeeding. */
13549 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
13550 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
13552 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
13557 case FUNCTION_TYPE:
13558 if (TREE_CODE (arg) != TREE_CODE (parm))
13561 /* CV qualifications for methods can never be deduced, they must
13562 match exactly. We need to check them explicitly here,
13563 because type_unification_real treats them as any other
13564 cv-qualified parameter. */
13565 if (TREE_CODE (parm) == METHOD_TYPE
13566 && (!check_cv_quals_for_unify
13568 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
13569 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
13572 if (unify (tparms, targs, TREE_TYPE (parm),
13573 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
13575 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
13576 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
13580 /* Unify a pointer to member with a pointer to member function, which
13581 deduces the type of the member as a function type. */
13582 if (TYPE_PTRMEMFUNC_P (arg))
13586 cp_cv_quals cv_quals;
13588 /* Check top-level cv qualifiers */
13589 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
13592 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
13593 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
13596 /* Determine the type of the function we are unifying against. */
13597 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
13599 build_function_type (TREE_TYPE (method_type),
13600 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
13602 /* Extract the cv-qualifiers of the member function from the
13603 implicit object parameter and place them on the function
13604 type to be restored later. */
13606 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
13607 fntype = build_qualified_type (fntype, cv_quals);
13608 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
13611 if (TREE_CODE (arg) != OFFSET_TYPE)
13613 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
13614 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
13616 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
13620 if (DECL_TEMPLATE_PARM_P (parm))
13621 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
13622 if (arg != integral_constant_value (parm))
13627 case TEMPLATE_DECL:
13628 /* Matched cases are handled by the ARG == PARM test above. */
13631 case TYPE_ARGUMENT_PACK:
13632 case NONTYPE_ARGUMENT_PACK:
13634 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
13635 tree packed_args = ARGUMENT_PACK_ARGS (arg);
13636 int i, len = TREE_VEC_LENGTH (packed_parms);
13637 int argslen = TREE_VEC_LENGTH (packed_args);
13638 int parm_variadic_p = 0;
13640 for (i = 0; i < len; ++i)
13642 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
13645 /* We can unify against something with a trailing
13647 parm_variadic_p = 1;
13649 /* Since there is something following the pack
13650 expansion, we cannot unify this template argument
13657 /* If we don't have enough arguments to satisfy the parameters
13658 (not counting the pack expression at the end), or we have
13659 too many arguments for a parameter list that doesn't end in
13660 a pack expression, we can't unify. */
13661 if (argslen < (len - parm_variadic_p)
13662 || (argslen > len && !parm_variadic_p))
13665 /* Unify all of the parameters that precede the (optional)
13666 pack expression. */
13667 for (i = 0; i < len - parm_variadic_p; ++i)
13669 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
13670 TREE_VEC_ELT (packed_args, i), strict))
13674 if (parm_variadic_p)
13675 return unify_pack_expansion (tparms, targs,
13676 packed_parms, packed_args,
13677 strict, /*call_args_p=*/false,
13685 case DECLTYPE_TYPE:
13686 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
13691 /* Unification fails if we hit an error node. */
13695 gcc_assert (EXPR_P (parm));
13697 /* We must be looking at an expression. This can happen with
13701 void foo(S<I>, S<I + 2>);
13703 This is a "nondeduced context":
13707 The nondeduced contexts are:
13709 --A type that is a template-id in which one or more of
13710 the template-arguments is an expression that references
13711 a template-parameter.
13713 In these cases, we assume deduction succeeded, but don't
13714 actually infer any unifications. */
13716 if (!uses_template_parms (parm)
13717 && !template_args_equal (parm, arg))
13724 /* Note that DECL can be defined in this translation unit, if
13728 mark_definable (tree decl)
13731 DECL_NOT_REALLY_EXTERN (decl) = 1;
13732 FOR_EACH_CLONE (clone, decl)
13733 DECL_NOT_REALLY_EXTERN (clone) = 1;
13736 /* Called if RESULT is explicitly instantiated, or is a member of an
13737 explicitly instantiated class. */
13740 mark_decl_instantiated (tree result, int extern_p)
13742 SET_DECL_EXPLICIT_INSTANTIATION (result);
13744 /* If this entity has already been written out, it's too late to
13745 make any modifications. */
13746 if (TREE_ASM_WRITTEN (result))
13749 if (TREE_CODE (result) != FUNCTION_DECL)
13750 /* The TREE_PUBLIC flag for function declarations will have been
13751 set correctly by tsubst. */
13752 TREE_PUBLIC (result) = 1;
13754 /* This might have been set by an earlier implicit instantiation. */
13755 DECL_COMDAT (result) = 0;
13758 DECL_NOT_REALLY_EXTERN (result) = 0;
13761 mark_definable (result);
13762 /* Always make artificials weak. */
13763 if (DECL_ARTIFICIAL (result) && flag_weak)
13764 comdat_linkage (result);
13765 /* For WIN32 we also want to put explicit instantiations in
13766 linkonce sections. */
13767 else if (TREE_PUBLIC (result))
13768 maybe_make_one_only (result);
13771 /* If EXTERN_P, then this function will not be emitted -- unless
13772 followed by an explicit instantiation, at which point its linkage
13773 will be adjusted. If !EXTERN_P, then this function will be
13774 emitted here. In neither circumstance do we want
13775 import_export_decl to adjust the linkage. */
13776 DECL_INTERFACE_KNOWN (result) = 1;
13779 /* Given two function templates PAT1 and PAT2, return:
13781 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
13782 -1 if PAT2 is more specialized than PAT1.
13783 0 if neither is more specialized.
13785 LEN indicates the number of parameters we should consider
13786 (defaulted parameters should not be considered).
13788 The 1998 std underspecified function template partial ordering, and
13789 DR214 addresses the issue. We take pairs of arguments, one from
13790 each of the templates, and deduce them against each other. One of
13791 the templates will be more specialized if all the *other*
13792 template's arguments deduce against its arguments and at least one
13793 of its arguments *does* *not* deduce against the other template's
13794 corresponding argument. Deduction is done as for class templates.
13795 The arguments used in deduction have reference and top level cv
13796 qualifiers removed. Iff both arguments were originally reference
13797 types *and* deduction succeeds in both directions, the template
13798 with the more cv-qualified argument wins for that pairing (if
13799 neither is more cv-qualified, they both are equal). Unlike regular
13800 deduction, after all the arguments have been deduced in this way,
13801 we do *not* verify the deduced template argument values can be
13802 substituted into non-deduced contexts, nor do we have to verify
13803 that all template arguments have been deduced. */
13806 more_specialized_fn (tree pat1, tree pat2, int len)
13808 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
13809 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
13810 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
13811 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
13812 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
13813 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
13814 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
13815 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
13819 /* Remove the this parameter from non-static member functions. If
13820 one is a non-static member function and the other is not a static
13821 member function, remove the first parameter from that function
13822 also. This situation occurs for operator functions where we
13823 locate both a member function (with this pointer) and non-member
13824 operator (with explicit first operand). */
13825 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
13827 len--; /* LEN is the number of significant arguments for DECL1 */
13828 args1 = TREE_CHAIN (args1);
13829 if (!DECL_STATIC_FUNCTION_P (decl2))
13830 args2 = TREE_CHAIN (args2);
13832 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
13834 args2 = TREE_CHAIN (args2);
13835 if (!DECL_STATIC_FUNCTION_P (decl1))
13838 args1 = TREE_CHAIN (args1);
13842 /* If only one is a conversion operator, they are unordered. */
13843 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
13846 /* Consider the return type for a conversion function */
13847 if (DECL_CONV_FN_P (decl1))
13849 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
13850 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
13854 processing_template_decl++;
13857 /* Stop when an ellipsis is seen. */
13858 && args1 != NULL_TREE && args2 != NULL_TREE)
13860 tree arg1 = TREE_VALUE (args1);
13861 tree arg2 = TREE_VALUE (args2);
13862 int deduce1, deduce2;
13866 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
13867 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
13869 /* When both arguments are pack expansions, we need only
13870 unify the patterns themselves. */
13871 arg1 = PACK_EXPANSION_PATTERN (arg1);
13872 arg2 = PACK_EXPANSION_PATTERN (arg2);
13874 /* This is the last comparison we need to do. */
13878 if (TREE_CODE (arg1) == REFERENCE_TYPE)
13880 arg1 = TREE_TYPE (arg1);
13881 quals1 = cp_type_quals (arg1);
13884 if (TREE_CODE (arg2) == REFERENCE_TYPE)
13886 arg2 = TREE_TYPE (arg2);
13887 quals2 = cp_type_quals (arg2);
13890 if ((quals1 < 0) != (quals2 < 0))
13892 /* Only of the args is a reference, see if we should apply
13893 array/function pointer decay to it. This is not part of
13894 DR214, but is, IMHO, consistent with the deduction rules
13895 for the function call itself, and with our earlier
13896 implementation of the underspecified partial ordering
13897 rules. (nathan). */
13900 switch (TREE_CODE (arg1))
13903 arg1 = TREE_TYPE (arg1);
13905 case FUNCTION_TYPE:
13906 arg1 = build_pointer_type (arg1);
13915 switch (TREE_CODE (arg2))
13918 arg2 = TREE_TYPE (arg2);
13920 case FUNCTION_TYPE:
13921 arg2 = build_pointer_type (arg2);
13930 arg1 = TYPE_MAIN_VARIANT (arg1);
13931 arg2 = TYPE_MAIN_VARIANT (arg2);
13933 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
13935 int i, len2 = list_length (args2);
13936 tree parmvec = make_tree_vec (1);
13937 tree argvec = make_tree_vec (len2);
13940 /* Setup the parameter vector, which contains only ARG1. */
13941 TREE_VEC_ELT (parmvec, 0) = arg1;
13943 /* Setup the argument vector, which contains the remaining
13945 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
13946 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
13948 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
13949 argvec, UNIFY_ALLOW_NONE,
13950 /*call_args_p=*/false,
13953 /* We cannot deduce in the other direction, because ARG1 is
13954 a pack expansion but ARG2 is not. */
13957 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
13959 int i, len1 = list_length (args1);
13960 tree parmvec = make_tree_vec (1);
13961 tree argvec = make_tree_vec (len1);
13964 /* Setup the parameter vector, which contains only ARG1. */
13965 TREE_VEC_ELT (parmvec, 0) = arg2;
13967 /* Setup the argument vector, which contains the remaining
13969 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
13970 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
13972 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
13973 argvec, UNIFY_ALLOW_NONE,
13974 /*call_args_p=*/false,
13977 /* We cannot deduce in the other direction, because ARG2 is
13978 a pack expansion but ARG1 is not.*/
13984 /* The normal case, where neither argument is a pack
13986 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
13987 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
13994 if (better1 < 0 && better2 < 0)
13995 /* We've failed to deduce something in either direction.
13996 These must be unordered. */
13999 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
14001 /* Deduces in both directions, see if quals can
14002 disambiguate. Pretend the worse one failed to deduce. */
14003 if ((quals1 & quals2) == quals2)
14005 if ((quals1 & quals2) == quals1)
14008 if (deduce1 && !deduce2 && !better2)
14010 if (deduce2 && !deduce1 && !better1)
14013 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
14014 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
14015 /* We have already processed all of the arguments in our
14016 handing of the pack expansion type. */
14019 args1 = TREE_CHAIN (args1);
14020 args2 = TREE_CHAIN (args2);
14023 processing_template_decl--;
14025 /* All things being equal, if the next argument is a pack expansion
14026 for one function but not for the other, prefer the
14027 non-variadic function. */
14028 if ((better1 > 0) - (better2 > 0) == 0
14029 && args1 && TREE_VALUE (args1)
14030 && args2 && TREE_VALUE (args2))
14032 if (TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION)
14033 return TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION ? 0 : -1;
14034 else if (TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION)
14038 return (better1 > 0) - (better2 > 0);
14041 /* Determine which of two partial specializations is more specialized.
14043 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
14044 to the first partial specialization. The TREE_VALUE is the
14045 innermost set of template parameters for the partial
14046 specialization. PAT2 is similar, but for the second template.
14048 Return 1 if the first partial specialization is more specialized;
14049 -1 if the second is more specialized; 0 if neither is more
14052 See [temp.class.order] for information about determining which of
14053 two templates is more specialized. */
14056 more_specialized_class (tree pat1, tree pat2)
14061 bool any_deductions = false;
14063 tmpl1 = TREE_TYPE (pat1);
14064 tmpl2 = TREE_TYPE (pat2);
14066 /* Just like what happens for functions, if we are ordering between
14067 different class template specializations, we may encounter dependent
14068 types in the arguments, and we need our dependency check functions
14069 to behave correctly. */
14070 ++processing_template_decl;
14071 targs = get_class_bindings (TREE_VALUE (pat1),
14072 CLASSTYPE_TI_ARGS (tmpl1),
14073 CLASSTYPE_TI_ARGS (tmpl2));
14077 any_deductions = true;
14080 targs = get_class_bindings (TREE_VALUE (pat2),
14081 CLASSTYPE_TI_ARGS (tmpl2),
14082 CLASSTYPE_TI_ARGS (tmpl1));
14086 any_deductions = true;
14088 --processing_template_decl;
14090 /* In the case of a tie where at least one of the class templates
14091 has a parameter pack at the end, the template with the most
14092 non-packed parameters wins. */
14095 && (template_args_variadic_p (TREE_PURPOSE (pat1))
14096 || template_args_variadic_p (TREE_PURPOSE (pat2))))
14098 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
14099 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
14100 int len1 = TREE_VEC_LENGTH (args1);
14101 int len2 = TREE_VEC_LENGTH (args2);
14103 /* We don't count the pack expansion at the end. */
14104 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
14106 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
14111 else if (len1 < len2)
14118 /* Return the template arguments that will produce the function signature
14119 DECL from the function template FN, with the explicit template
14120 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
14121 also match. Return NULL_TREE if no satisfactory arguments could be
14125 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
14127 int ntparms = DECL_NTPARMS (fn);
14128 tree targs = make_tree_vec (ntparms);
14130 tree decl_arg_types;
14132 /* Substitute the explicit template arguments into the type of DECL.
14133 The call to fn_type_unification will handle substitution into the
14135 decl_type = TREE_TYPE (decl);
14136 if (explicit_args && uses_template_parms (decl_type))
14139 tree converted_args;
14141 if (DECL_TEMPLATE_INFO (decl))
14142 tmpl = DECL_TI_TEMPLATE (decl);
14144 /* We can get here for some invalid specializations. */
14148 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
14149 explicit_args, NULL_TREE,
14151 /*require_all_args=*/false,
14152 /*use_default_args=*/false);
14153 if (converted_args == error_mark_node)
14156 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
14157 if (decl_type == error_mark_node)
14161 /* Never do unification on the 'this' parameter. */
14162 decl_arg_types = skip_artificial_parms_for (decl,
14163 TYPE_ARG_TYPES (decl_type));
14165 if (fn_type_unification (fn, explicit_args, targs,
14167 (check_rettype || DECL_CONV_FN_P (fn)
14168 ? TREE_TYPE (decl_type) : NULL_TREE),
14169 DEDUCE_EXACT, LOOKUP_NORMAL))
14175 /* Return the innermost template arguments that, when applied to a
14176 template specialization whose innermost template parameters are
14177 TPARMS, and whose specialization arguments are PARMS, yield the
14180 For example, suppose we have:
14182 template <class T, class U> struct S {};
14183 template <class T> struct S<T*, int> {};
14185 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
14186 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
14187 int}. The resulting vector will be {double}, indicating that `T'
14188 is bound to `double'. */
14191 get_class_bindings (tree tparms, tree spec_args, tree args)
14193 int i, ntparms = TREE_VEC_LENGTH (tparms);
14195 tree innermost_deduced_args;
14197 innermost_deduced_args = make_tree_vec (ntparms);
14198 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
14200 deduced_args = copy_node (args);
14201 SET_TMPL_ARGS_LEVEL (deduced_args,
14202 TMPL_ARGS_DEPTH (deduced_args),
14203 innermost_deduced_args);
14206 deduced_args = innermost_deduced_args;
14208 if (unify (tparms, deduced_args,
14209 INNERMOST_TEMPLATE_ARGS (spec_args),
14210 INNERMOST_TEMPLATE_ARGS (args),
14214 for (i = 0; i < ntparms; ++i)
14215 if (! TREE_VEC_ELT (innermost_deduced_args, i))
14218 /* Verify that nondeduced template arguments agree with the type
14219 obtained from argument deduction.
14223 struct A { typedef int X; };
14224 template <class T, class U> struct C {};
14225 template <class T> struct C<T, typename T::X> {};
14227 Then with the instantiation `C<A, int>', we can deduce that
14228 `T' is `A' but unify () does not check whether `typename T::X'
14230 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
14231 if (spec_args == error_mark_node
14232 /* We only need to check the innermost arguments; the other
14233 arguments will always agree. */
14234 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
14235 INNERMOST_TEMPLATE_ARGS (args)))
14238 /* Now that we have bindings for all of the template arguments,
14239 ensure that the arguments deduced for the template template
14240 parameters have compatible template parameter lists. See the use
14241 of template_template_parm_bindings_ok_p in fn_type_unification
14242 for more information. */
14243 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
14246 return deduced_args;
14249 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
14250 Return the TREE_LIST node with the most specialized template, if
14251 any. If there is no most specialized template, the error_mark_node
14254 Note that this function does not look at, or modify, the
14255 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
14256 returned is one of the elements of INSTANTIATIONS, callers may
14257 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
14258 and retrieve it from the value returned. */
14261 most_specialized_instantiation (tree templates)
14265 ++processing_template_decl;
14268 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
14272 if (get_bindings (TREE_VALUE (champ),
14273 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
14274 NULL_TREE, /*check_ret=*/false))
14277 if (get_bindings (TREE_VALUE (fn),
14278 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
14279 NULL_TREE, /*check_ret=*/false))
14286 /* Equally specialized, move to next function. If there
14287 is no next function, nothing's most specialized. */
14288 fn = TREE_CHAIN (fn);
14296 /* Now verify that champ is better than everything earlier in the
14297 instantiation list. */
14298 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
14299 if (get_bindings (TREE_VALUE (champ),
14300 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
14301 NULL_TREE, /*check_ret=*/false)
14302 || !get_bindings (TREE_VALUE (fn),
14303 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
14304 NULL_TREE, /*check_ret=*/false))
14310 processing_template_decl--;
14313 return error_mark_node;
14318 /* If DECL is a specialization of some template, return the most
14319 general such template. Otherwise, returns NULL_TREE.
14321 For example, given:
14323 template <class T> struct S { template <class U> void f(U); };
14325 if TMPL is `template <class U> void S<int>::f(U)' this will return
14326 the full template. This function will not trace past partial
14327 specializations, however. For example, given in addition:
14329 template <class T> struct S<T*> { template <class U> void f(U); };
14331 if TMPL is `template <class U> void S<int*>::f(U)' this will return
14332 `template <class T> template <class U> S<T*>::f(U)'. */
14335 most_general_template (tree decl)
14337 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
14338 an immediate specialization. */
14339 if (TREE_CODE (decl) == FUNCTION_DECL)
14341 if (DECL_TEMPLATE_INFO (decl)) {
14342 decl = DECL_TI_TEMPLATE (decl);
14344 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
14345 template friend. */
14346 if (TREE_CODE (decl) != TEMPLATE_DECL)
14352 /* Look for more and more general templates. */
14353 while (DECL_TEMPLATE_INFO (decl))
14355 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
14356 (See cp-tree.h for details.) */
14357 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
14360 if (CLASS_TYPE_P (TREE_TYPE (decl))
14361 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
14364 /* Stop if we run into an explicitly specialized class template. */
14365 if (!DECL_NAMESPACE_SCOPE_P (decl)
14366 && DECL_CONTEXT (decl)
14367 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
14370 decl = DECL_TI_TEMPLATE (decl);
14376 /* Return the most specialized of the class template partial
14377 specializations of TMPL which can produce TYPE, a specialization of
14378 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
14379 a _TYPE node corresponding to the partial specialization, while the
14380 TREE_PURPOSE is the set of template arguments that must be
14381 substituted into the TREE_TYPE in order to generate TYPE.
14383 If the choice of partial specialization is ambiguous, a diagnostic
14384 is issued, and the error_mark_node is returned. If there are no
14385 partial specializations of TMPL matching TYPE, then NULL_TREE is
14389 most_specialized_class (tree type, tree tmpl)
14391 tree list = NULL_TREE;
14397 tree outer_args = NULL_TREE;
14399 tmpl = most_general_template (tmpl);
14400 args = CLASSTYPE_TI_ARGS (type);
14402 /* For determining which partial specialization to use, only the
14403 innermost args are interesting. */
14404 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
14406 outer_args = strip_innermost_template_args (args, 1);
14407 args = INNERMOST_TEMPLATE_ARGS (args);
14410 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
14412 tree partial_spec_args;
14414 tree parms = TREE_VALUE (t);
14416 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
14421 ++processing_template_decl;
14423 /* Discard the outer levels of args, and then substitute in the
14424 template args from the enclosing class. */
14425 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
14426 partial_spec_args = tsubst_template_args
14427 (partial_spec_args, outer_args, tf_none, NULL_TREE);
14429 /* PARMS already refers to just the innermost parms, but the
14430 template parms in partial_spec_args had their levels lowered
14431 by tsubst, so we need to do the same for the parm list. We
14432 can't just tsubst the TREE_VEC itself, as tsubst wants to
14433 treat a TREE_VEC as an argument vector. */
14434 parms = copy_node (parms);
14435 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
14436 TREE_VEC_ELT (parms, i) =
14437 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
14439 --processing_template_decl;
14441 spec_args = get_class_bindings (parms,
14447 spec_args = add_to_template_args (outer_args, spec_args);
14448 list = tree_cons (spec_args, TREE_VALUE (t), list);
14449 TREE_TYPE (list) = TREE_TYPE (t);
14456 ambiguous_p = false;
14459 t = TREE_CHAIN (t);
14460 for (; t; t = TREE_CHAIN (t))
14462 fate = more_specialized_class (champ, t);
14469 t = TREE_CHAIN (t);
14472 ambiguous_p = true;
14481 for (t = list; t && t != champ; t = TREE_CHAIN (t))
14483 fate = more_specialized_class (champ, t);
14486 ambiguous_p = true;
14493 const char *str = "candidates are:";
14494 error ("ambiguous class template instantiation for %q#T", type);
14495 for (t = list; t; t = TREE_CHAIN (t))
14497 error ("%s %+#T", str, TREE_TYPE (t));
14500 return error_mark_node;
14506 /* Explicitly instantiate DECL. */
14509 do_decl_instantiation (tree decl, tree storage)
14511 tree result = NULL_TREE;
14514 if (!decl || decl == error_mark_node)
14515 /* An error occurred, for which grokdeclarator has already issued
14516 an appropriate message. */
14518 else if (! DECL_LANG_SPECIFIC (decl))
14520 error ("explicit instantiation of non-template %q#D", decl);
14523 else if (TREE_CODE (decl) == VAR_DECL)
14525 /* There is an asymmetry here in the way VAR_DECLs and
14526 FUNCTION_DECLs are handled by grokdeclarator. In the case of
14527 the latter, the DECL we get back will be marked as a
14528 template instantiation, and the appropriate
14529 DECL_TEMPLATE_INFO will be set up. This does not happen for
14530 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
14531 should handle VAR_DECLs as it currently handles
14533 if (!DECL_CLASS_SCOPE_P (decl))
14535 error ("%qD is not a static data member of a class template", decl);
14538 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
14539 if (!result || TREE_CODE (result) != VAR_DECL)
14541 error ("no matching template for %qD found", decl);
14544 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
14546 error ("type %qT for explicit instantiation %qD does not match "
14547 "declared type %qT", TREE_TYPE (result), decl,
14552 else if (TREE_CODE (decl) != FUNCTION_DECL)
14554 error ("explicit instantiation of %q#D", decl);
14560 /* Check for various error cases. Note that if the explicit
14561 instantiation is valid the RESULT will currently be marked as an
14562 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
14563 until we get here. */
14565 if (DECL_TEMPLATE_SPECIALIZATION (result))
14567 /* DR 259 [temp.spec].
14569 Both an explicit instantiation and a declaration of an explicit
14570 specialization shall not appear in a program unless the explicit
14571 instantiation follows a declaration of the explicit specialization.
14573 For a given set of template parameters, if an explicit
14574 instantiation of a template appears after a declaration of an
14575 explicit specialization for that template, the explicit
14576 instantiation has no effect. */
14579 else if (DECL_EXPLICIT_INSTANTIATION (result))
14583 No program shall explicitly instantiate any template more
14586 We check DECL_NOT_REALLY_EXTERN so as not to complain when
14587 the first instantiation was `extern' and the second is not,
14588 and EXTERN_P for the opposite case. */
14589 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
14590 permerror ("duplicate explicit instantiation of %q#D", result);
14591 /* If an "extern" explicit instantiation follows an ordinary
14592 explicit instantiation, the template is instantiated. */
14596 else if (!DECL_IMPLICIT_INSTANTIATION (result))
14598 error ("no matching template for %qD found", result);
14601 else if (!DECL_TEMPLATE_INFO (result))
14603 permerror ("explicit instantiation of non-template %q#D", result);
14607 if (storage == NULL_TREE)
14609 else if (storage == ridpointers[(int) RID_EXTERN])
14611 if (!in_system_header && (cxx_dialect == cxx98))
14612 pedwarn (OPT_pedantic,
14613 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
14618 error ("storage class %qD applied to template instantiation", storage);
14620 check_explicit_instantiation_namespace (result);
14621 mark_decl_instantiated (result, extern_p);
14623 instantiate_decl (result, /*defer_ok=*/1,
14624 /*expl_inst_class_mem_p=*/false);
14628 mark_class_instantiated (tree t, int extern_p)
14630 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
14631 SET_CLASSTYPE_INTERFACE_KNOWN (t);
14632 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
14633 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
14636 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
14637 rest_of_type_compilation (t, 1);
14641 /* Called from do_type_instantiation through binding_table_foreach to
14642 do recursive instantiation for the type bound in ENTRY. */
14644 bt_instantiate_type_proc (binding_entry entry, void *data)
14646 tree storage = *(tree *) data;
14648 if (MAYBE_CLASS_TYPE_P (entry->type)
14649 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
14650 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
14653 /* Called from do_type_instantiation to instantiate a member
14654 (a member function or a static member variable) of an
14655 explicitly instantiated class template. */
14657 instantiate_class_member (tree decl, int extern_p)
14659 mark_decl_instantiated (decl, extern_p);
14661 instantiate_decl (decl, /*defer_ok=*/1,
14662 /*expl_inst_class_mem_p=*/true);
14665 /* Perform an explicit instantiation of template class T. STORAGE, if
14666 non-null, is the RID for extern, inline or static. COMPLAIN is
14667 nonzero if this is called from the parser, zero if called recursively,
14668 since the standard is unclear (as detailed below). */
14671 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
14676 int previous_instantiation_extern_p = 0;
14678 if (TREE_CODE (t) == TYPE_DECL)
14681 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
14683 error ("explicit instantiation of non-template type %qT", t);
14689 if (!COMPLETE_TYPE_P (t))
14691 if (complain & tf_error)
14692 error ("explicit instantiation of %q#T before definition of template",
14697 if (storage != NULL_TREE)
14699 if (!in_system_header)
14701 if (storage == ridpointers[(int) RID_EXTERN])
14703 if (cxx_dialect == cxx98)
14704 pedwarn(OPT_pedantic,
14705 "ISO C++ 1998 forbids the use of %<extern%> on "
14706 "explicit instantiations");
14709 pedwarn(OPT_pedantic, "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;
14923 else if (TREE_CODE (decl) == VAR_DECL)
14924 DECL_INITIAL (decl) =
14925 tsubst_expr (DECL_INITIAL (code_pattern), args,
14926 tf_error, DECL_TI_TEMPLATE (decl),
14927 /*integral_constant_expression_p=*/false);
14929 gcc_unreachable ();
14931 pop_access_scope (decl);
14934 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
14935 substituted to get DECL. */
14938 template_for_substitution (tree decl)
14940 tree tmpl = DECL_TI_TEMPLATE (decl);
14942 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
14943 for the instantiation. This is not always the most general
14944 template. Consider, for example:
14947 struct S { template <class U> void f();
14948 template <> void f<int>(); };
14950 and an instantiation of S<double>::f<int>. We want TD to be the
14951 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
14952 while (/* An instantiation cannot have a definition, so we need a
14953 more general template. */
14954 DECL_TEMPLATE_INSTANTIATION (tmpl)
14955 /* We must also deal with friend templates. Given:
14957 template <class T> struct S {
14958 template <class U> friend void f() {};
14961 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
14962 so far as the language is concerned, but that's still
14963 where we get the pattern for the instantiation from. On
14964 other hand, if the definition comes outside the class, say:
14966 template <class T> struct S {
14967 template <class U> friend void f();
14969 template <class U> friend void f() {}
14971 we don't need to look any further. That's what the check for
14972 DECL_INITIAL is for. */
14973 || (TREE_CODE (decl) == FUNCTION_DECL
14974 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
14975 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
14977 /* The present template, TD, should not be a definition. If it
14978 were a definition, we should be using it! Note that we
14979 cannot restructure the loop to just keep going until we find
14980 a template with a definition, since that might go too far if
14981 a specialization was declared, but not defined. */
14982 gcc_assert (TREE_CODE (decl) != VAR_DECL
14983 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
14985 /* Fetch the more general template. */
14986 tmpl = DECL_TI_TEMPLATE (tmpl);
14992 /* Produce the definition of D, a _DECL generated from a template. If
14993 DEFER_OK is nonzero, then we don't have to actually do the
14994 instantiation now; we just have to do it sometime. Normally it is
14995 an error if this is an explicit instantiation but D is undefined.
14996 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
14997 explicitly instantiated class template. */
15000 instantiate_decl (tree d, int defer_ok,
15001 bool expl_inst_class_mem_p)
15003 tree tmpl = DECL_TI_TEMPLATE (d);
15010 bool pattern_defined;
15012 location_t saved_loc = input_location;
15015 /* This function should only be used to instantiate templates for
15016 functions and static member variables. */
15017 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
15018 || TREE_CODE (d) == VAR_DECL);
15020 /* Variables are never deferred; if instantiation is required, they
15021 are instantiated right away. That allows for better code in the
15022 case that an expression refers to the value of the variable --
15023 if the variable has a constant value the referring expression can
15024 take advantage of that fact. */
15025 if (TREE_CODE (d) == VAR_DECL)
15028 /* Don't instantiate cloned functions. Instead, instantiate the
15029 functions they cloned. */
15030 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
15031 d = DECL_CLONED_FUNCTION (d);
15033 if (DECL_TEMPLATE_INSTANTIATED (d))
15034 /* D has already been instantiated. It might seem reasonable to
15035 check whether or not D is an explicit instantiation, and, if so,
15036 stop here. But when an explicit instantiation is deferred
15037 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
15038 is set, even though we still need to do the instantiation. */
15041 /* If we already have a specialization of this declaration, then
15042 there's no reason to instantiate it. Note that
15043 retrieve_specialization gives us both instantiations and
15044 specializations, so we must explicitly check
15045 DECL_TEMPLATE_SPECIALIZATION. */
15046 gen_tmpl = most_general_template (tmpl);
15047 gen_args = DECL_TI_ARGS (d);
15048 spec = retrieve_specialization (gen_tmpl, gen_args,
15049 /*class_specializations_p=*/false);
15050 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
15053 /* This needs to happen before any tsubsting. */
15054 if (! push_tinst_level (d))
15057 timevar_push (TV_PARSE);
15059 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
15060 for the instantiation. */
15061 td = template_for_substitution (d);
15062 code_pattern = DECL_TEMPLATE_RESULT (td);
15064 /* We should never be trying to instantiate a member of a class
15065 template or partial specialization. */
15066 gcc_assert (d != code_pattern);
15068 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
15069 || DECL_TEMPLATE_SPECIALIZATION (td))
15070 /* In the case of a friend template whose definition is provided
15071 outside the class, we may have too many arguments. Drop the
15072 ones we don't need. The same is true for specializations. */
15073 args = get_innermost_template_args
15074 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
15078 if (TREE_CODE (d) == FUNCTION_DECL)
15079 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
15081 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
15083 /* We may be in the middle of deferred access check. Disable it now. */
15084 push_deferring_access_checks (dk_no_deferred);
15086 /* Unless an explicit instantiation directive has already determined
15087 the linkage of D, remember that a definition is available for
15089 if (pattern_defined
15090 && !DECL_INTERFACE_KNOWN (d)
15091 && !DECL_NOT_REALLY_EXTERN (d))
15092 mark_definable (d);
15094 input_location = DECL_SOURCE_LOCATION (d);
15096 /* If D is a member of an explicitly instantiated class template,
15097 and no definition is available, treat it like an implicit
15099 if (!pattern_defined && expl_inst_class_mem_p
15100 && DECL_EXPLICIT_INSTANTIATION (d))
15102 DECL_NOT_REALLY_EXTERN (d) = 0;
15103 DECL_INTERFACE_KNOWN (d) = 0;
15104 SET_DECL_IMPLICIT_INSTANTIATION (d);
15109 /* Recheck the substitutions to obtain any warning messages
15110 about ignoring cv qualifiers. */
15111 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
15112 tree type = TREE_TYPE (gen);
15114 /* Make sure that we can see identifiers, and compute access
15115 correctly. D is already the target FUNCTION_DECL with the
15117 push_access_scope (d);
15119 if (TREE_CODE (gen) == FUNCTION_DECL)
15121 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
15122 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
15124 /* Don't simply tsubst the function type, as that will give
15125 duplicate warnings about poor parameter qualifications.
15126 The function arguments are the same as the decl_arguments
15127 without the top level cv qualifiers. */
15128 type = TREE_TYPE (type);
15130 tsubst (type, gen_args, tf_warning_or_error, d);
15132 pop_access_scope (d);
15135 /* Check to see whether we know that this template will be
15136 instantiated in some other file, as with "extern template"
15138 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
15139 /* In general, we do not instantiate such templates... */
15141 /* ... but we instantiate inline functions so that we can inline
15143 && ! (TREE_CODE (d) == FUNCTION_DECL
15144 && possibly_inlined_p (d))
15145 /* ... we instantiate static data members whose values are
15146 needed in integral constant expressions. */
15147 && ! (TREE_CODE (d) == VAR_DECL
15148 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
15150 /* Defer all other templates, unless we have been explicitly
15151 forbidden from doing so. */
15152 if (/* If there is no definition, we cannot instantiate the
15155 /* If it's OK to postpone instantiation, do so. */
15157 /* If this is a static data member that will be defined
15158 elsewhere, we don't want to instantiate the entire data
15159 member, but we do want to instantiate the initializer so that
15160 we can substitute that elsewhere. */
15161 || (external_p && TREE_CODE (d) == VAR_DECL))
15163 /* The definition of the static data member is now required so
15164 we must substitute the initializer. */
15165 if (TREE_CODE (d) == VAR_DECL
15166 && !DECL_INITIAL (d)
15167 && DECL_INITIAL (code_pattern))
15172 ns = decl_namespace_context (d);
15173 push_nested_namespace (ns);
15174 push_nested_class (DECL_CONTEXT (d));
15175 init = tsubst_expr (DECL_INITIAL (code_pattern),
15177 tf_warning_or_error, NULL_TREE,
15178 /*integral_constant_expression_p=*/false);
15179 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
15180 /*asmspec_tree=*/NULL_TREE,
15181 LOOKUP_ONLYCONVERTING);
15182 pop_nested_class ();
15183 pop_nested_namespace (ns);
15186 /* We restore the source position here because it's used by
15187 add_pending_template. */
15188 input_location = saved_loc;
15190 if (at_eof && !pattern_defined
15191 && DECL_EXPLICIT_INSTANTIATION (d))
15194 The definition of a non-exported function template, a
15195 non-exported member function template, or a non-exported
15196 member function or static data member of a class template
15197 shall be present in every translation unit in which it is
15198 explicitly instantiated. */
15200 ("explicit instantiation of %qD but no definition available", d);
15202 /* ??? Historically, we have instantiated inline functions, even
15203 when marked as "extern template". */
15204 if (!(external_p && TREE_CODE (d) == VAR_DECL))
15205 add_pending_template (d);
15208 /* Tell the repository that D is available in this translation unit
15209 -- and see if it is supposed to be instantiated here. */
15210 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
15212 /* In a PCH file, despite the fact that the repository hasn't
15213 requested instantiation in the PCH it is still possible that
15214 an instantiation will be required in a file that includes the
15217 add_pending_template (d);
15218 /* Instantiate inline functions so that the inliner can do its
15219 job, even though we'll not be emitting a copy of this
15221 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
15225 need_push = !cfun || !global_bindings_p ();
15227 push_to_top_level ();
15229 /* Mark D as instantiated so that recursive calls to
15230 instantiate_decl do not try to instantiate it again. */
15231 DECL_TEMPLATE_INSTANTIATED (d) = 1;
15233 /* Regenerate the declaration in case the template has been modified
15234 by a subsequent redeclaration. */
15235 regenerate_decl_from_template (d, td);
15237 /* We already set the file and line above. Reset them now in case
15238 they changed as a result of calling regenerate_decl_from_template. */
15239 input_location = DECL_SOURCE_LOCATION (d);
15241 if (TREE_CODE (d) == VAR_DECL)
15245 /* Clear out DECL_RTL; whatever was there before may not be right
15246 since we've reset the type of the declaration. */
15247 SET_DECL_RTL (d, NULL_RTX);
15248 DECL_IN_AGGR_P (d) = 0;
15250 /* The initializer is placed in DECL_INITIAL by
15251 regenerate_decl_from_template. Pull it out so that
15252 finish_decl can process it. */
15253 init = DECL_INITIAL (d);
15254 DECL_INITIAL (d) = NULL_TREE;
15255 DECL_INITIALIZED_P (d) = 0;
15257 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
15258 initializer. That function will defer actual emission until
15259 we have a chance to determine linkage. */
15260 DECL_EXTERNAL (d) = 0;
15262 /* Enter the scope of D so that access-checking works correctly. */
15263 push_nested_class (DECL_CONTEXT (d));
15264 finish_decl (d, init, NULL_TREE);
15265 pop_nested_class ();
15267 else if (TREE_CODE (d) == FUNCTION_DECL)
15269 htab_t saved_local_specializations;
15274 /* Save away the current list, in case we are instantiating one
15275 template from within the body of another. */
15276 saved_local_specializations = local_specializations;
15278 /* Set up the list of local specializations. */
15279 local_specializations = htab_create (37,
15280 hash_local_specialization,
15281 eq_local_specializations,
15284 /* Set up context. */
15285 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
15287 /* Create substitution entries for the parameters. */
15288 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
15289 tmpl_parm = DECL_ARGUMENTS (subst_decl);
15290 spec_parm = DECL_ARGUMENTS (d);
15291 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
15293 register_local_specialization (spec_parm, tmpl_parm);
15294 spec_parm = skip_artificial_parms_for (d, spec_parm);
15295 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
15297 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
15299 register_local_specialization (spec_parm, tmpl_parm);
15300 tmpl_parm = TREE_CHAIN (tmpl_parm);
15301 spec_parm = TREE_CHAIN (spec_parm);
15303 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
15305 /* Collect all of the extra "packed" parameters into an
15309 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
15310 tree argtypepack = make_node (TYPE_ARGUMENT_PACK);
15314 /* Count how many parameters remain. */
15315 for (t = spec_parm; t; t = TREE_CHAIN (t))
15318 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
15319 parmvec = make_tree_vec (len);
15320 parmtypevec = make_tree_vec (len);
15321 for(i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
15323 TREE_VEC_ELT (parmvec, i) = spec_parm;
15324 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
15327 /* Build the argument packs. */
15328 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
15329 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
15330 TREE_TYPE (argpack) = argtypepack;
15332 /* Register the (value) argument pack as a specialization of
15333 TMPL_PARM, then move on. */
15334 register_local_specialization (argpack, tmpl_parm);
15335 tmpl_parm = TREE_CHAIN (tmpl_parm);
15337 gcc_assert (!spec_parm);
15339 /* Substitute into the body of the function. */
15340 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
15341 tf_warning_or_error, tmpl,
15342 /*integral_constant_expression_p=*/false);
15344 /* Set the current input_location to the end of the function
15345 so that finish_function knows where we are. */
15346 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
15348 /* We don't need the local specializations any more. */
15349 htab_delete (local_specializations);
15350 local_specializations = saved_local_specializations;
15352 /* Finish the function. */
15353 d = finish_function (0);
15354 expand_or_defer_fn (d);
15357 /* We're not deferring instantiation any more. */
15358 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
15361 pop_from_top_level ();
15364 input_location = saved_loc;
15365 pop_deferring_access_checks ();
15366 pop_tinst_level ();
15368 timevar_pop (TV_PARSE);
15373 /* Run through the list of templates that we wish we could
15374 instantiate, and instantiate any we can. RETRIES is the
15375 number of times we retry pending template instantiation. */
15378 instantiate_pending_templates (int retries)
15381 location_t saved_loc = input_location;
15383 /* Instantiating templates may trigger vtable generation. This in turn
15384 may require further template instantiations. We place a limit here
15385 to avoid infinite loop. */
15386 if (pending_templates && retries >= max_tinst_depth)
15388 tree decl = pending_templates->tinst->decl;
15390 error ("template instantiation depth exceeds maximum of %d"
15391 " instantiating %q+D, possibly from virtual table generation"
15392 " (use -ftemplate-depth-NN to increase the maximum)",
15393 max_tinst_depth, decl);
15394 if (TREE_CODE (decl) == FUNCTION_DECL)
15395 /* Pretend that we defined it. */
15396 DECL_INITIAL (decl) = error_mark_node;
15402 struct pending_template **t = &pending_templates;
15403 struct pending_template *last = NULL;
15407 tree instantiation = reopen_tinst_level ((*t)->tinst);
15408 bool complete = false;
15410 if (TYPE_P (instantiation))
15414 if (!COMPLETE_TYPE_P (instantiation))
15416 instantiate_class_template (instantiation);
15417 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
15418 for (fn = TYPE_METHODS (instantiation);
15420 fn = TREE_CHAIN (fn))
15421 if (! DECL_ARTIFICIAL (fn))
15422 instantiate_decl (fn,
15424 /*expl_inst_class_mem_p=*/false);
15425 if (COMPLETE_TYPE_P (instantiation))
15429 complete = COMPLETE_TYPE_P (instantiation);
15433 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
15434 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
15437 = instantiate_decl (instantiation,
15439 /*expl_inst_class_mem_p=*/false);
15440 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
15444 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
15445 || DECL_TEMPLATE_INSTANTIATED (instantiation));
15449 /* If INSTANTIATION has been instantiated, then we don't
15450 need to consider it again in the future. */
15458 current_tinst_level = NULL;
15460 last_pending_template = last;
15462 while (reconsider);
15464 input_location = saved_loc;
15467 /* Substitute ARGVEC into T, which is a list of initializers for
15468 either base class or a non-static data member. The TREE_PURPOSEs
15469 are DECLs, and the TREE_VALUEs are the initializer values. Used by
15470 instantiate_decl. */
15473 tsubst_initializer_list (tree t, tree argvec)
15475 tree inits = NULL_TREE;
15477 for (; t; t = TREE_CHAIN (t))
15481 tree expanded_bases = NULL_TREE;
15482 tree expanded_arguments = NULL_TREE;
15485 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
15490 /* Expand the base class expansion type into separate base
15492 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
15493 tf_warning_or_error,
15495 if (expanded_bases == error_mark_node)
15498 /* We'll be building separate TREE_LISTs of arguments for
15500 len = TREE_VEC_LENGTH (expanded_bases);
15501 expanded_arguments = make_tree_vec (len);
15502 for (i = 0; i < len; i++)
15503 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
15505 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
15506 expand each argument in the TREE_VALUE of t. */
15507 expr = make_node (EXPR_PACK_EXPANSION);
15508 PACK_EXPANSION_PARAMETER_PACKS (expr) =
15509 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
15511 if (TREE_VALUE (t) == void_type_node)
15512 /* VOID_TYPE_NODE is used to indicate
15513 value-initialization. */
15515 for (i = 0; i < len; i++)
15516 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
15520 /* Substitute parameter packs into each argument in the
15522 in_base_initializer = 1;
15523 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
15525 tree expanded_exprs;
15527 /* Expand the argument. */
15528 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
15530 = tsubst_pack_expansion (expr, argvec,
15531 tf_warning_or_error,
15533 if (expanded_exprs == error_mark_node)
15536 /* Prepend each of the expanded expressions to the
15537 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
15538 for (i = 0; i < len; i++)
15540 TREE_VEC_ELT (expanded_arguments, i) =
15541 tree_cons (NULL_TREE,
15542 TREE_VEC_ELT (expanded_exprs, i),
15543 TREE_VEC_ELT (expanded_arguments, i));
15546 in_base_initializer = 0;
15548 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
15549 since we built them backwards. */
15550 for (i = 0; i < len; i++)
15552 TREE_VEC_ELT (expanded_arguments, i) =
15553 nreverse (TREE_VEC_ELT (expanded_arguments, i));
15558 for (i = 0; i < len; ++i)
15560 if (expanded_bases)
15562 decl = TREE_VEC_ELT (expanded_bases, i);
15563 decl = expand_member_init (decl);
15564 init = TREE_VEC_ELT (expanded_arguments, i);
15568 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
15569 tf_warning_or_error, NULL_TREE);
15571 decl = expand_member_init (decl);
15572 if (decl && !DECL_P (decl))
15573 in_base_initializer = 1;
15575 init = tsubst_expr (TREE_VALUE (t), argvec,
15576 tf_warning_or_error, NULL_TREE,
15577 /*integral_constant_expression_p=*/false);
15578 in_base_initializer = 0;
15583 init = build_tree_list (decl, init);
15584 TREE_CHAIN (init) = inits;
15592 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
15595 set_current_access_from_decl (tree decl)
15597 if (TREE_PRIVATE (decl))
15598 current_access_specifier = access_private_node;
15599 else if (TREE_PROTECTED (decl))
15600 current_access_specifier = access_protected_node;
15602 current_access_specifier = access_public_node;
15605 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
15606 is the instantiation (which should have been created with
15607 start_enum) and ARGS are the template arguments to use. */
15610 tsubst_enum (tree tag, tree newtag, tree args)
15614 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
15619 decl = TREE_VALUE (e);
15620 /* Note that in a template enum, the TREE_VALUE is the
15621 CONST_DECL, not the corresponding INTEGER_CST. */
15622 value = tsubst_expr (DECL_INITIAL (decl),
15623 args, tf_warning_or_error, NULL_TREE,
15624 /*integral_constant_expression_p=*/true);
15626 /* Give this enumeration constant the correct access. */
15627 set_current_access_from_decl (decl);
15629 /* Actually build the enumerator itself. */
15630 build_enumerator (DECL_NAME (decl), value, newtag);
15633 finish_enum (newtag);
15634 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
15635 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
15638 /* DECL is a FUNCTION_DECL that is a template specialization. Return
15639 its type -- but without substituting the innermost set of template
15640 arguments. So, innermost set of template parameters will appear in
15644 get_mostly_instantiated_function_type (tree decl)
15652 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
15653 targs = DECL_TI_ARGS (decl);
15654 tparms = DECL_TEMPLATE_PARMS (tmpl);
15655 parm_depth = TMPL_PARMS_DEPTH (tparms);
15657 /* There should be as many levels of arguments as there are levels
15659 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
15661 fn_type = TREE_TYPE (tmpl);
15663 if (parm_depth == 1)
15664 /* No substitution is necessary. */
15668 int i, save_access_control;
15671 /* Replace the innermost level of the TARGS with NULL_TREEs to
15672 let tsubst know not to substitute for those parameters. */
15673 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
15674 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
15675 SET_TMPL_ARGS_LEVEL (partial_args, i,
15676 TMPL_ARGS_LEVEL (targs, i));
15677 SET_TMPL_ARGS_LEVEL (partial_args,
15678 TMPL_ARGS_DEPTH (targs),
15679 make_tree_vec (DECL_NTPARMS (tmpl)));
15681 /* Disable access control as this function is used only during
15683 save_access_control = flag_access_control;
15684 flag_access_control = 0;
15686 ++processing_template_decl;
15687 /* Now, do the (partial) substitution to figure out the
15688 appropriate function type. */
15689 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
15690 --processing_template_decl;
15692 /* Substitute into the template parameters to obtain the real
15693 innermost set of parameters. This step is important if the
15694 innermost set of template parameters contains value
15695 parameters whose types depend on outer template parameters. */
15696 TREE_VEC_LENGTH (partial_args)--;
15697 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
15699 flag_access_control = save_access_control;
15705 /* Return truthvalue if we're processing a template different from
15706 the last one involved in diagnostics. */
15708 problematic_instantiation_changed (void)
15710 return last_template_error_tick != tinst_level_tick;
15713 /* Remember current template involved in diagnostics. */
15715 record_last_problematic_instantiation (void)
15717 last_template_error_tick = tinst_level_tick;
15720 struct tinst_level *
15721 current_instantiation (void)
15723 return current_tinst_level;
15726 /* [temp.param] Check that template non-type parm TYPE is of an allowable
15727 type. Return zero for ok, nonzero for disallowed. Issue error and
15728 warning messages under control of COMPLAIN. */
15731 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
15733 if (INTEGRAL_TYPE_P (type))
15735 else if (POINTER_TYPE_P (type))
15737 else if (TYPE_PTR_TO_MEMBER_P (type))
15739 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
15741 else if (TREE_CODE (type) == TYPENAME_TYPE)
15744 if (complain & tf_error)
15745 error ("%q#T is not a valid type for a template constant parameter", type);
15749 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
15750 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
15753 dependent_type_p_r (tree type)
15759 A type is dependent if it is:
15761 -- a template parameter. Template template parameters are types
15762 for us (since TYPE_P holds true for them) so we handle
15764 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
15765 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
15767 /* -- a qualified-id with a nested-name-specifier which contains a
15768 class-name that names a dependent type or whose unqualified-id
15769 names a dependent type. */
15770 if (TREE_CODE (type) == TYPENAME_TYPE)
15772 /* -- a cv-qualified type where the cv-unqualified type is
15774 type = TYPE_MAIN_VARIANT (type);
15775 /* -- a compound type constructed from any dependent type. */
15776 if (TYPE_PTR_TO_MEMBER_P (type))
15777 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
15778 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
15780 else if (TREE_CODE (type) == POINTER_TYPE
15781 || TREE_CODE (type) == REFERENCE_TYPE)
15782 return dependent_type_p (TREE_TYPE (type));
15783 else if (TREE_CODE (type) == FUNCTION_TYPE
15784 || TREE_CODE (type) == METHOD_TYPE)
15788 if (dependent_type_p (TREE_TYPE (type)))
15790 for (arg_type = TYPE_ARG_TYPES (type);
15792 arg_type = TREE_CHAIN (arg_type))
15793 if (dependent_type_p (TREE_VALUE (arg_type)))
15797 /* -- an array type constructed from any dependent type or whose
15798 size is specified by a constant expression that is
15799 value-dependent. */
15800 if (TREE_CODE (type) == ARRAY_TYPE)
15802 if (TYPE_DOMAIN (type)
15803 && dependent_type_p (TYPE_DOMAIN (type)))
15805 return dependent_type_p (TREE_TYPE (type));
15807 else if (TREE_CODE (type) == INTEGER_TYPE
15808 && !TREE_CONSTANT (TYPE_MAX_VALUE (type)))
15810 /* If this is the TYPE_DOMAIN of an array type, consider it
15812 return (value_dependent_expression_p (TYPE_MAX_VALUE (type))
15813 || type_dependent_expression_p (TYPE_MAX_VALUE (type)));
15816 /* -- a template-id in which either the template name is a template
15818 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
15820 /* ... or any of the template arguments is a dependent type or
15821 an expression that is type-dependent or value-dependent. */
15822 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
15823 && (any_dependent_template_arguments_p
15824 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
15827 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
15828 argument of the `typeof' expression is not type-dependent, then
15829 it should already been have resolved. */
15830 if (TREE_CODE (type) == TYPEOF_TYPE
15831 || TREE_CODE (type) == DECLTYPE_TYPE)
15834 /* A template argument pack is dependent if any of its packed
15836 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
15838 tree args = ARGUMENT_PACK_ARGS (type);
15839 int i, len = TREE_VEC_LENGTH (args);
15840 for (i = 0; i < len; ++i)
15841 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
15845 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
15846 be template parameters. */
15847 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
15850 /* The standard does not specifically mention types that are local
15851 to template functions or local classes, but they should be
15852 considered dependent too. For example:
15854 template <int I> void f() {
15859 The size of `E' cannot be known until the value of `I' has been
15860 determined. Therefore, `E' must be considered dependent. */
15861 scope = TYPE_CONTEXT (type);
15862 if (scope && TYPE_P (scope))
15863 return dependent_type_p (scope);
15864 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
15865 return type_dependent_expression_p (scope);
15867 /* Other types are non-dependent. */
15871 /* Returns TRUE if TYPE is dependent, in the sense of
15872 [temp.dep.type]. */
15875 dependent_type_p (tree type)
15877 /* If there are no template parameters in scope, then there can't be
15878 any dependent types. */
15879 if (!processing_template_decl)
15881 /* If we are not processing a template, then nobody should be
15882 providing us with a dependent type. */
15884 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM);
15888 /* If the type is NULL, we have not computed a type for the entity
15889 in question; in that case, the type is dependent. */
15893 /* Erroneous types can be considered non-dependent. */
15894 if (type == error_mark_node)
15897 /* If we have not already computed the appropriate value for TYPE,
15899 if (!TYPE_DEPENDENT_P_VALID (type))
15901 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
15902 TYPE_DEPENDENT_P_VALID (type) = 1;
15905 return TYPE_DEPENDENT_P (type);
15908 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
15911 dependent_scope_ref_p (tree expression, bool criterion (tree))
15916 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
15918 if (!TYPE_P (TREE_OPERAND (expression, 0)))
15921 scope = TREE_OPERAND (expression, 0);
15922 name = TREE_OPERAND (expression, 1);
15926 An id-expression is type-dependent if it contains a
15927 nested-name-specifier that contains a class-name that names a
15929 /* The suggested resolution to Core Issue 2 implies that if the
15930 qualifying type is the current class, then we must peek
15933 && currently_open_class (scope)
15934 && !criterion (name))
15936 if (dependent_type_p (scope))
15942 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
15943 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
15947 value_dependent_expression_p (tree expression)
15949 if (!processing_template_decl)
15952 /* A name declared with a dependent type. */
15953 if (DECL_P (expression) && type_dependent_expression_p (expression))
15956 switch (TREE_CODE (expression))
15958 case IDENTIFIER_NODE:
15959 /* A name that has not been looked up -- must be dependent. */
15962 case TEMPLATE_PARM_INDEX:
15963 /* A non-type template parm. */
15967 /* A non-type template parm. */
15968 if (DECL_TEMPLATE_PARM_P (expression))
15970 return value_dependent_expression_p (DECL_INITIAL (expression));
15973 /* A constant with integral or enumeration type and is initialized
15974 with an expression that is value-dependent. */
15975 if (DECL_INITIAL (expression)
15976 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
15977 && value_dependent_expression_p (DECL_INITIAL (expression)))
15981 case DYNAMIC_CAST_EXPR:
15982 case STATIC_CAST_EXPR:
15983 case CONST_CAST_EXPR:
15984 case REINTERPRET_CAST_EXPR:
15986 /* These expressions are value-dependent if the type to which
15987 the cast occurs is dependent or the expression being casted
15988 is value-dependent. */
15990 tree type = TREE_TYPE (expression);
15992 if (dependent_type_p (type))
15995 /* A functional cast has a list of operands. */
15996 expression = TREE_OPERAND (expression, 0);
15999 /* If there are no operands, it must be an expression such
16000 as "int()". This should not happen for aggregate types
16001 because it would form non-constant expressions. */
16002 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
16007 if (TREE_CODE (expression) == TREE_LIST)
16008 return any_value_dependent_elements_p (expression);
16010 return value_dependent_expression_p (expression);
16015 /* A `sizeof' expression is value-dependent if the operand is
16016 type-dependent or is a pack expansion. */
16017 expression = TREE_OPERAND (expression, 0);
16018 if (PACK_EXPANSION_P (expression))
16020 else if (TYPE_P (expression))
16021 return dependent_type_p (expression);
16022 return type_dependent_expression_p (expression);
16025 return dependent_scope_ref_p (expression, value_dependent_expression_p);
16027 case COMPONENT_REF:
16028 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
16029 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
16032 /* A CALL_EXPR may appear in a constant expression if it is a
16033 call to a builtin function, e.g., __builtin_constant_p. All
16034 such calls are value-dependent. */
16037 case NONTYPE_ARGUMENT_PACK:
16038 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
16039 is value-dependent. */
16041 tree values = ARGUMENT_PACK_ARGS (expression);
16042 int i, len = TREE_VEC_LENGTH (values);
16044 for (i = 0; i < len; ++i)
16045 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
16053 tree type2 = TRAIT_EXPR_TYPE2 (expression);
16054 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
16055 || (type2 ? dependent_type_p (type2) : false));
16059 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
16060 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
16063 /* A constant expression is value-dependent if any subexpression is
16064 value-dependent. */
16065 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
16067 case tcc_reference:
16069 return (value_dependent_expression_p
16070 (TREE_OPERAND (expression, 0)));
16072 case tcc_comparison:
16074 return ((value_dependent_expression_p
16075 (TREE_OPERAND (expression, 0)))
16076 || (value_dependent_expression_p
16077 (TREE_OPERAND (expression, 1))));
16079 case tcc_expression:
16083 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
16084 /* In some cases, some of the operands may be missing.
16085 (For example, in the case of PREDECREMENT_EXPR, the
16086 amount to increment by may be missing.) That doesn't
16087 make the expression dependent. */
16088 if (TREE_OPERAND (expression, i)
16089 && (value_dependent_expression_p
16090 (TREE_OPERAND (expression, i))))
16100 /* The expression is not value-dependent. */
16104 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
16105 [temp.dep.expr]. */
16108 type_dependent_expression_p (tree expression)
16110 if (!processing_template_decl)
16113 if (expression == error_mark_node)
16116 /* An unresolved name is always dependent. */
16117 if (TREE_CODE (expression) == IDENTIFIER_NODE
16118 || TREE_CODE (expression) == USING_DECL)
16121 /* Some expression forms are never type-dependent. */
16122 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
16123 || TREE_CODE (expression) == SIZEOF_EXPR
16124 || TREE_CODE (expression) == ALIGNOF_EXPR
16125 || TREE_CODE (expression) == TRAIT_EXPR
16126 || TREE_CODE (expression) == TYPEID_EXPR
16127 || TREE_CODE (expression) == DELETE_EXPR
16128 || TREE_CODE (expression) == VEC_DELETE_EXPR
16129 || TREE_CODE (expression) == THROW_EXPR)
16132 /* The types of these expressions depends only on the type to which
16133 the cast occurs. */
16134 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
16135 || TREE_CODE (expression) == STATIC_CAST_EXPR
16136 || TREE_CODE (expression) == CONST_CAST_EXPR
16137 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
16138 || TREE_CODE (expression) == CAST_EXPR)
16139 return dependent_type_p (TREE_TYPE (expression));
16141 /* The types of these expressions depends only on the type created
16142 by the expression. */
16143 if (TREE_CODE (expression) == NEW_EXPR
16144 || TREE_CODE (expression) == VEC_NEW_EXPR)
16146 /* For NEW_EXPR tree nodes created inside a template, either
16147 the object type itself or a TREE_LIST may appear as the
16149 tree type = TREE_OPERAND (expression, 1);
16150 if (TREE_CODE (type) == TREE_LIST)
16151 /* This is an array type. We need to check array dimensions
16153 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
16154 || value_dependent_expression_p
16155 (TREE_OPERAND (TREE_VALUE (type), 1));
16157 return dependent_type_p (type);
16160 if (TREE_CODE (expression) == SCOPE_REF
16161 && dependent_scope_ref_p (expression,
16162 type_dependent_expression_p))
16165 if (TREE_CODE (expression) == FUNCTION_DECL
16166 && DECL_LANG_SPECIFIC (expression)
16167 && DECL_TEMPLATE_INFO (expression)
16168 && (any_dependent_template_arguments_p
16169 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
16172 if (TREE_CODE (expression) == TEMPLATE_DECL
16173 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
16176 if (TREE_CODE (expression) == STMT_EXPR)
16177 expression = stmt_expr_value_expr (expression);
16179 if (TREE_TYPE (expression) == unknown_type_node)
16181 if (TREE_CODE (expression) == ADDR_EXPR)
16182 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
16183 if (TREE_CODE (expression) == COMPONENT_REF
16184 || TREE_CODE (expression) == OFFSET_REF)
16186 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
16188 expression = TREE_OPERAND (expression, 1);
16189 if (TREE_CODE (expression) == IDENTIFIER_NODE)
16192 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
16193 if (TREE_CODE (expression) == SCOPE_REF)
16196 if (TREE_CODE (expression) == BASELINK)
16197 expression = BASELINK_FUNCTIONS (expression);
16199 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
16201 if (any_dependent_template_arguments_p
16202 (TREE_OPERAND (expression, 1)))
16204 expression = TREE_OPERAND (expression, 0);
16206 gcc_assert (TREE_CODE (expression) == OVERLOAD
16207 || TREE_CODE (expression) == FUNCTION_DECL);
16211 if (type_dependent_expression_p (OVL_CURRENT (expression)))
16213 expression = OVL_NEXT (expression);
16218 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
16220 return (dependent_type_p (TREE_TYPE (expression)));
16223 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
16224 contains a type-dependent expression. */
16227 any_type_dependent_arguments_p (const_tree args)
16231 tree arg = TREE_VALUE (args);
16233 if (type_dependent_expression_p (arg))
16235 args = TREE_CHAIN (args);
16240 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
16241 expressions) contains any value-dependent expressions. */
16244 any_value_dependent_elements_p (const_tree list)
16246 for (; list; list = TREE_CHAIN (list))
16247 if (value_dependent_expression_p (TREE_VALUE (list)))
16253 /* Returns TRUE if the ARG (a template argument) is dependent. */
16256 dependent_template_arg_p (tree arg)
16258 if (!processing_template_decl)
16261 if (TREE_CODE (arg) == TEMPLATE_DECL
16262 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
16263 return dependent_template_p (arg);
16264 else if (ARGUMENT_PACK_P (arg))
16266 tree args = ARGUMENT_PACK_ARGS (arg);
16267 int i, len = TREE_VEC_LENGTH (args);
16268 for (i = 0; i < len; ++i)
16270 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
16276 else if (TYPE_P (arg))
16277 return dependent_type_p (arg);
16279 return (type_dependent_expression_p (arg)
16280 || value_dependent_expression_p (arg));
16283 /* Returns true if ARGS (a collection of template arguments) contains
16284 any types that require structural equality testing. */
16287 any_template_arguments_need_structural_equality_p (tree args)
16294 if (args == error_mark_node)
16297 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
16299 tree level = TMPL_ARGS_LEVEL (args, i + 1);
16300 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
16302 tree arg = TREE_VEC_ELT (level, j);
16303 tree packed_args = NULL_TREE;
16306 if (ARGUMENT_PACK_P (arg))
16308 /* Look inside the argument pack. */
16309 packed_args = ARGUMENT_PACK_ARGS (arg);
16310 len = TREE_VEC_LENGTH (packed_args);
16313 for (k = 0; k < len; ++k)
16316 arg = TREE_VEC_ELT (packed_args, k);
16318 if (error_operand_p (arg))
16320 else if (TREE_CODE (arg) == TEMPLATE_DECL
16321 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
16323 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
16325 else if (!TYPE_P (arg) && TREE_TYPE (arg)
16326 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
16335 /* Returns true if ARGS (a collection of template arguments) contains
16336 any dependent arguments. */
16339 any_dependent_template_arguments_p (const_tree args)
16346 if (args == error_mark_node)
16349 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
16351 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
16352 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
16353 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
16360 /* Returns TRUE if the template TMPL is dependent. */
16363 dependent_template_p (tree tmpl)
16365 if (TREE_CODE (tmpl) == OVERLOAD)
16369 if (dependent_template_p (OVL_FUNCTION (tmpl)))
16371 tmpl = OVL_CHAIN (tmpl);
16376 /* Template template parameters are dependent. */
16377 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
16378 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
16380 /* So are names that have not been looked up. */
16381 if (TREE_CODE (tmpl) == SCOPE_REF
16382 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
16384 /* So are member templates of dependent classes. */
16385 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
16386 return dependent_type_p (DECL_CONTEXT (tmpl));
16390 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
16393 dependent_template_id_p (tree tmpl, tree args)
16395 return (dependent_template_p (tmpl)
16396 || any_dependent_template_arguments_p (args));
16399 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
16403 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
16407 if (!processing_template_decl)
16410 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
16412 tree decl = TREE_VEC_ELT (declv, i);
16413 tree init = TREE_VEC_ELT (initv, i);
16414 tree cond = TREE_VEC_ELT (condv, i);
16415 tree incr = TREE_VEC_ELT (incrv, i);
16417 if (type_dependent_expression_p (decl))
16420 if (init && type_dependent_expression_p (init))
16423 if (type_dependent_expression_p (cond))
16426 if (COMPARISON_CLASS_P (cond)
16427 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
16428 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
16431 if (TREE_CODE (incr) == MODOP_EXPR)
16433 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
16434 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
16437 else if (type_dependent_expression_p (incr))
16439 else if (TREE_CODE (incr) == MODIFY_EXPR)
16441 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
16443 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
16445 tree t = TREE_OPERAND (incr, 1);
16446 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
16447 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
16456 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
16457 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
16458 no such TYPE can be found. Note that this function peers inside
16459 uninstantiated templates and therefore should be used only in
16460 extremely limited situations. ONLY_CURRENT_P restricts this
16461 peering to the currently open classes hierarchy (which is required
16462 when comparing types). */
16465 resolve_typename_type (tree type, bool only_current_p)
16474 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
16476 scope = TYPE_CONTEXT (type);
16477 name = TYPE_IDENTIFIER (type);
16479 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
16480 it first before we can figure out what NAME refers to. */
16481 if (TREE_CODE (scope) == TYPENAME_TYPE)
16482 scope = resolve_typename_type (scope, only_current_p);
16483 /* If we don't know what SCOPE refers to, then we cannot resolve the
16485 if (TREE_CODE (scope) == TYPENAME_TYPE)
16487 /* If the SCOPE is a template type parameter, we have no way of
16488 resolving the name. */
16489 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
16491 /* If the SCOPE is not the current instantiation, there's no reason
16492 to look inside it. */
16493 if (only_current_p && !currently_open_class (scope))
16495 /* If SCOPE isn't the template itself, it will not have a valid
16496 TYPE_FIELDS list. */
16497 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
16498 /* scope is either the template itself or a compatible instantiation
16499 like X<T>, so look up the name in the original template. */
16500 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
16502 /* scope is a partial instantiation, so we can't do the lookup or we
16503 will lose the template arguments. */
16505 /* Enter the SCOPE so that name lookup will be resolved as if we
16506 were in the class definition. In particular, SCOPE will no
16507 longer be considered a dependent type. */
16508 pushed_scope = push_scope (scope);
16509 /* Look up the declaration. */
16510 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
16512 result = NULL_TREE;
16514 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
16515 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
16518 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
16519 && TREE_CODE (decl) == TYPE_DECL)
16521 result = TREE_TYPE (decl);
16522 if (result == error_mark_node)
16523 result = NULL_TREE;
16525 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
16526 && DECL_CLASS_TEMPLATE_P (decl))
16530 /* Obtain the template and the arguments. */
16531 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
16532 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
16533 /* Instantiate the template. */
16534 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
16535 /*entering_scope=*/0,
16536 tf_error | tf_user);
16537 if (result == error_mark_node)
16538 result = NULL_TREE;
16541 /* Leave the SCOPE. */
16543 pop_scope (pushed_scope);
16545 /* If we failed to resolve it, return the original typename. */
16549 /* If lookup found a typename type, resolve that too. */
16550 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
16552 /* Ill-formed programs can cause infinite recursion here, so we
16553 must catch that. */
16554 TYPENAME_IS_RESOLVING_P (type) = 1;
16555 result = resolve_typename_type (result, only_current_p);
16556 TYPENAME_IS_RESOLVING_P (type) = 0;
16559 /* Qualify the resulting type. */
16560 quals = cp_type_quals (type);
16562 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
16567 /* EXPR is an expression which is not type-dependent. Return a proxy
16568 for EXPR that can be used to compute the types of larger
16569 expressions containing EXPR. */
16572 build_non_dependent_expr (tree expr)
16576 /* Preserve null pointer constants so that the type of things like
16577 "p == 0" where "p" is a pointer can be determined. */
16578 if (null_ptr_cst_p (expr))
16580 /* Preserve OVERLOADs; the functions must be available to resolve
16583 if (TREE_CODE (inner_expr) == STMT_EXPR)
16584 inner_expr = stmt_expr_value_expr (inner_expr);
16585 if (TREE_CODE (inner_expr) == ADDR_EXPR)
16586 inner_expr = TREE_OPERAND (inner_expr, 0);
16587 if (TREE_CODE (inner_expr) == COMPONENT_REF)
16588 inner_expr = TREE_OPERAND (inner_expr, 1);
16589 if (is_overloaded_fn (inner_expr)
16590 || TREE_CODE (inner_expr) == OFFSET_REF)
16592 /* There is no need to return a proxy for a variable. */
16593 if (TREE_CODE (expr) == VAR_DECL)
16595 /* Preserve string constants; conversions from string constants to
16596 "char *" are allowed, even though normally a "const char *"
16597 cannot be used to initialize a "char *". */
16598 if (TREE_CODE (expr) == STRING_CST)
16600 /* Preserve arithmetic constants, as an optimization -- there is no
16601 reason to create a new node. */
16602 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
16604 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
16605 There is at least one place where we want to know that a
16606 particular expression is a throw-expression: when checking a ?:
16607 expression, there are special rules if the second or third
16608 argument is a throw-expression. */
16609 if (TREE_CODE (expr) == THROW_EXPR)
16612 if (TREE_CODE (expr) == COND_EXPR)
16613 return build3 (COND_EXPR,
16615 TREE_OPERAND (expr, 0),
16616 (TREE_OPERAND (expr, 1)
16617 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
16618 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
16619 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
16620 if (TREE_CODE (expr) == COMPOUND_EXPR
16621 && !COMPOUND_EXPR_OVERLOADED (expr))
16622 return build2 (COMPOUND_EXPR,
16624 TREE_OPERAND (expr, 0),
16625 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
16627 /* If the type is unknown, it can't really be non-dependent */
16628 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
16630 /* Otherwise, build a NON_DEPENDENT_EXPR.
16632 REFERENCE_TYPEs are not stripped for expressions in templates
16633 because doing so would play havoc with mangling. Consider, for
16636 template <typename T> void f<T& g>() { g(); }
16638 In the body of "f", the expression for "g" will have
16639 REFERENCE_TYPE, even though the standard says that it should
16640 not. The reason is that we must preserve the syntactic form of
16641 the expression so that mangling (say) "f<g>" inside the body of
16642 "f" works out correctly. Therefore, the REFERENCE_TYPE is
16644 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
16647 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
16648 Return a new TREE_LIST with the various arguments replaced with
16649 equivalent non-dependent expressions. */
16652 build_non_dependent_args (tree args)
16657 new_args = NULL_TREE;
16658 for (a = args; a; a = TREE_CHAIN (a))
16659 new_args = tree_cons (NULL_TREE,
16660 build_non_dependent_expr (TREE_VALUE (a)),
16662 return nreverse (new_args);
16665 #include "gt-cp-pt.h"