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 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*);
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 int template_args_equal (tree, tree);
162 static void tsubst_default_arguments (tree);
163 static tree for_each_template_parm_r (tree *, int *, void *);
164 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
165 static void copy_default_args_to_explicit_spec (tree);
166 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
167 static int eq_local_specializations (const void *, const void *);
168 static bool dependent_template_arg_p (tree);
169 static bool any_template_arguments_need_structural_equality_p (tree);
170 static bool dependent_type_p_r (tree);
171 static tree tsubst (tree, tree, tsubst_flags_t, tree);
172 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
173 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
174 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
176 /* Make the current scope suitable for access checking when we are
177 processing T. T can be FUNCTION_DECL for instantiated function
178 template, or VAR_DECL for static member variable (need by
179 instantiate_decl). */
182 push_access_scope (tree t)
184 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
185 || TREE_CODE (t) == VAR_DECL);
187 if (DECL_FRIEND_CONTEXT (t))
188 push_nested_class (DECL_FRIEND_CONTEXT (t));
189 else if (DECL_CLASS_SCOPE_P (t))
190 push_nested_class (DECL_CONTEXT (t));
192 push_to_top_level ();
194 if (TREE_CODE (t) == FUNCTION_DECL)
196 saved_access_scope = tree_cons
197 (NULL_TREE, current_function_decl, saved_access_scope);
198 current_function_decl = t;
202 /* Restore the scope set up by push_access_scope. T is the node we
206 pop_access_scope (tree t)
208 if (TREE_CODE (t) == FUNCTION_DECL)
210 current_function_decl = TREE_VALUE (saved_access_scope);
211 saved_access_scope = TREE_CHAIN (saved_access_scope);
214 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
217 pop_from_top_level ();
220 /* Do any processing required when DECL (a member template
221 declaration) is finished. Returns the TEMPLATE_DECL corresponding
222 to DECL, unless it is a specialization, in which case the DECL
223 itself is returned. */
226 finish_member_template_decl (tree decl)
228 if (decl == error_mark_node)
229 return error_mark_node;
231 gcc_assert (DECL_P (decl));
233 if (TREE_CODE (decl) == TYPE_DECL)
237 type = TREE_TYPE (decl);
238 if (IS_AGGR_TYPE (type)
239 && CLASSTYPE_TEMPLATE_INFO (type)
240 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
242 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
243 check_member_template (tmpl);
248 else if (TREE_CODE (decl) == FIELD_DECL)
249 error ("data member %qD cannot be a member template", decl);
250 else if (DECL_TEMPLATE_INFO (decl))
252 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
254 check_member_template (DECL_TI_TEMPLATE (decl));
255 return DECL_TI_TEMPLATE (decl);
261 error ("invalid member template declaration %qD", decl);
263 return error_mark_node;
266 /* Return the template info node corresponding to T, whatever T is. */
269 get_template_info (tree t)
271 tree tinfo = NULL_TREE;
273 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
274 tinfo = DECL_TEMPLATE_INFO (t);
276 if (!tinfo && TREE_CODE (t) == TYPE_DECL)
279 if (TAGGED_TYPE_P (t))
280 tinfo = TYPE_TEMPLATE_INFO (t);
285 /* Returns the template nesting level of the indicated class TYPE.
295 A<T>::B<U> has depth two, while A<T> has depth one.
296 Both A<T>::B<int> and A<int>::B<U> have depth one, if
297 they are instantiations, not specializations.
299 This function is guaranteed to return 0 if passed NULL_TREE so
300 that, for example, `template_class_depth (current_class_type)' is
304 template_class_depth (tree type)
309 type && TREE_CODE (type) != NAMESPACE_DECL;
310 type = (TREE_CODE (type) == FUNCTION_DECL)
311 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
313 tree tinfo = get_template_info (type);
315 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
316 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
323 /* Subroutine of maybe_begin_member_template_processing.
324 Returns true if processing DECL needs us to push template parms. */
327 inline_needs_template_parms (tree decl)
329 if (! DECL_TEMPLATE_INFO (decl))
332 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
333 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
336 /* Subroutine of maybe_begin_member_template_processing.
337 Push the template parms in PARMS, starting from LEVELS steps into the
338 chain, and ending at the beginning, since template parms are listed
342 push_inline_template_parms_recursive (tree parmlist, int levels)
344 tree parms = TREE_VALUE (parmlist);
348 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
350 ++processing_template_decl;
351 current_template_parms
352 = tree_cons (size_int (processing_template_decl),
353 parms, current_template_parms);
354 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
356 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
358 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
360 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
362 if (parm == error_mark_node)
365 gcc_assert (DECL_P (parm));
367 switch (TREE_CODE (parm))
376 /* Make a CONST_DECL as is done in process_template_parm.
377 It is ugly that we recreate this here; the original
378 version built in process_template_parm is no longer
380 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
382 DECL_ARTIFICIAL (decl) = 1;
383 TREE_CONSTANT (decl) = 1;
384 TREE_INVARIANT (decl) = 1;
385 TREE_READONLY (decl) = 1;
386 DECL_INITIAL (decl) = DECL_INITIAL (parm);
387 SET_DECL_TEMPLATE_PARM_P (decl);
398 /* Restore the template parameter context for a member template or
399 a friend template defined in a class definition. */
402 maybe_begin_member_template_processing (tree decl)
407 if (inline_needs_template_parms (decl))
409 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
410 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
412 if (DECL_TEMPLATE_SPECIALIZATION (decl))
415 parms = TREE_CHAIN (parms);
418 push_inline_template_parms_recursive (parms, levels);
421 /* Remember how many levels of template parameters we pushed so that
422 we can pop them later. */
423 VEC_safe_push (int, heap, inline_parm_levels, levels);
426 /* Undo the effects of maybe_begin_member_template_processing. */
429 maybe_end_member_template_processing (void)
434 if (VEC_length (int, inline_parm_levels) == 0)
437 last = VEC_pop (int, inline_parm_levels);
438 for (i = 0; i < last; ++i)
440 --processing_template_decl;
441 current_template_parms = TREE_CHAIN (current_template_parms);
446 /* Return a new template argument vector which contains all of ARGS,
447 but has as its innermost set of arguments the EXTRA_ARGS. */
450 add_to_template_args (tree args, tree extra_args)
457 extra_depth = TMPL_ARGS_DEPTH (extra_args);
458 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
460 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
461 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
463 for (j = 1; j <= extra_depth; ++j, ++i)
464 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
469 /* Like add_to_template_args, but only the outermost ARGS are added to
470 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
471 (EXTRA_ARGS) levels are added. This function is used to combine
472 the template arguments from a partial instantiation with the
473 template arguments used to attain the full instantiation from the
474 partial instantiation. */
477 add_outermost_template_args (tree args, tree extra_args)
481 /* If there are more levels of EXTRA_ARGS than there are ARGS,
482 something very fishy is going on. */
483 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
485 /* If *all* the new arguments will be the EXTRA_ARGS, just return
487 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
490 /* For the moment, we make ARGS look like it contains fewer levels. */
491 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
493 new_args = add_to_template_args (args, extra_args);
495 /* Now, we restore ARGS to its full dimensions. */
496 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
501 /* Return the N levels of innermost template arguments from the ARGS. */
504 get_innermost_template_args (tree args, int n)
512 /* If N is 1, just return the innermost set of template arguments. */
514 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
516 /* If we're not removing anything, just return the arguments we were
518 extra_levels = TMPL_ARGS_DEPTH (args) - n;
519 gcc_assert (extra_levels >= 0);
520 if (extra_levels == 0)
523 /* Make a new set of arguments, not containing the outer arguments. */
524 new_args = make_tree_vec (n);
525 for (i = 1; i <= n; ++i)
526 SET_TMPL_ARGS_LEVEL (new_args, i,
527 TMPL_ARGS_LEVEL (args, i + extra_levels));
532 /* The inverse of get_innermost_template_args: Return all but the innermost
533 EXTRA_LEVELS levels of template arguments from the ARGS. */
536 strip_innermost_template_args (tree args, int extra_levels)
539 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
544 /* If N is 1, just return the outermost set of template arguments. */
546 return TMPL_ARGS_LEVEL (args, 1);
548 /* If we're not removing anything, just return the arguments we were
550 gcc_assert (extra_levels >= 0);
551 if (extra_levels == 0)
554 /* Make a new set of arguments, not containing the inner arguments. */
555 new_args = make_tree_vec (n);
556 for (i = 1; i <= n; ++i)
557 SET_TMPL_ARGS_LEVEL (new_args, i,
558 TMPL_ARGS_LEVEL (args, i));
563 /* We've got a template header coming up; push to a new level for storing
567 begin_template_parm_list (void)
569 /* We use a non-tag-transparent scope here, which causes pushtag to
570 put tags in this scope, rather than in the enclosing class or
571 namespace scope. This is the right thing, since we want
572 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
573 global template class, push_template_decl handles putting the
574 TEMPLATE_DECL into top-level scope. For a nested template class,
577 template <class T> struct S1 {
578 template <class T> struct S2 {};
581 pushtag contains special code to call pushdecl_with_scope on the
582 TEMPLATE_DECL for S2. */
583 begin_scope (sk_template_parms, NULL);
584 ++processing_template_decl;
585 ++processing_template_parmlist;
586 note_template_header (0);
589 /* This routine is called when a specialization is declared. If it is
590 invalid to declare a specialization here, an error is reported and
591 false is returned, otherwise this routine will return true. */
594 check_specialization_scope (void)
596 tree scope = current_scope ();
600 An explicit specialization shall be declared in the namespace of
601 which the template is a member, or, for member templates, in the
602 namespace of which the enclosing class or enclosing class
603 template is a member. An explicit specialization of a member
604 function, member class or static data member of a class template
605 shall be declared in the namespace of which the class template
607 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
609 error ("explicit specialization in non-namespace scope %qD", scope);
615 In an explicit specialization declaration for a member of a class
616 template or a member template that appears in namespace scope,
617 the member template and some of its enclosing class templates may
618 remain unspecialized, except that the declaration shall not
619 explicitly specialize a class member template if its enclosing
620 class templates are not explicitly specialized as well. */
621 if (current_template_parms)
623 error ("enclosing class templates are not explicitly specialized");
630 /* We've just seen template <>. */
633 begin_specialization (void)
635 begin_scope (sk_template_spec, NULL);
636 note_template_header (1);
637 return check_specialization_scope ();
640 /* Called at then end of processing a declaration preceded by
644 end_specialization (void)
647 reset_specialization ();
650 /* Any template <>'s that we have seen thus far are not referring to a
651 function specialization. */
654 reset_specialization (void)
656 processing_specialization = 0;
657 template_header_count = 0;
660 /* We've just seen a template header. If SPECIALIZATION is nonzero,
661 it was of the form template <>. */
664 note_template_header (int specialization)
666 processing_specialization = specialization;
667 template_header_count++;
670 /* We're beginning an explicit instantiation. */
673 begin_explicit_instantiation (void)
675 gcc_assert (!processing_explicit_instantiation);
676 processing_explicit_instantiation = true;
681 end_explicit_instantiation (void)
683 gcc_assert (processing_explicit_instantiation);
684 processing_explicit_instantiation = false;
687 /* An explicit specialization or partial specialization TMPL is being
688 declared. Check that the namespace in which the specialization is
689 occurring is permissible. Returns false iff it is invalid to
690 specialize TMPL in the current namespace. */
693 check_specialization_namespace (tree tmpl)
695 tree tpl_ns = decl_namespace_context (tmpl);
699 An explicit specialization shall be declared in the namespace of
700 which the template is a member, or, for member templates, in the
701 namespace of which the enclosing class or enclosing class
702 template is a member. An explicit specialization of a member
703 function, member class or static data member of a class template
704 shall be declared in the namespace of which the class template is
706 if (is_associated_namespace (current_namespace, tpl_ns))
707 /* Same or super-using namespace. */
711 pedwarn ("specialization of %qD in different namespace", tmpl);
712 pedwarn (" from definition of %q+#D", tmpl);
717 /* SPEC is an explicit instantiation. Check that it is valid to
718 perform this explicit instantiation in the current namespace. */
721 check_explicit_instantiation_namespace (tree spec)
725 /* DR 275: An explicit instantiation shall appear in an enclosing
726 namespace of its template. */
727 ns = decl_namespace_context (spec);
728 if (!is_ancestor (current_namespace, ns))
729 pedwarn ("explicit instantiation of %qD in namespace %qD "
730 "(which does not enclose namespace %qD)",
731 spec, current_namespace, ns);
734 /* The TYPE is being declared. If it is a template type, that means it
735 is a partial specialization. Do appropriate error-checking. */
738 maybe_process_partial_specialization (tree type)
742 if (type == error_mark_node)
743 return error_mark_node;
745 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
747 error ("name of class shadows template template parameter %qD",
749 return error_mark_node;
752 context = TYPE_CONTEXT (type);
754 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
756 /* This is for ordinary explicit specialization and partial
757 specialization of a template class such as:
759 template <> class C<int>;
763 template <class T> class C<T*>;
765 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
767 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
768 && !COMPLETE_TYPE_P (type))
770 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
771 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
772 if (processing_template_decl)
773 push_template_decl (TYPE_MAIN_DECL (type));
775 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
776 error ("specialization of %qT after instantiation", type);
778 else if (CLASS_TYPE_P (type)
779 && !CLASSTYPE_USE_TEMPLATE (type)
780 && CLASSTYPE_TEMPLATE_INFO (type)
781 && context && CLASS_TYPE_P (context)
782 && CLASSTYPE_TEMPLATE_INFO (context))
784 /* This is for an explicit specialization of member class
785 template according to [temp.expl.spec/18]:
787 template <> template <class U> class C<int>::D;
789 The context `C<int>' must be an implicit instantiation.
790 Otherwise this is just a member class template declared
793 template <> class C<int> { template <class U> class D; };
794 template <> template <class U> class C<int>::D;
796 In the first case, `C<int>::D' is a specialization of `C<T>::D'
797 while in the second case, `C<int>::D' is a primary template
798 and `C<T>::D' may not exist. */
800 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
801 && !COMPLETE_TYPE_P (type))
805 if (current_namespace
806 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
808 pedwarn ("specializing %q#T in different namespace", type);
809 pedwarn (" from definition of %q+#D",
810 CLASSTYPE_TI_TEMPLATE (type));
813 /* Check for invalid specialization after instantiation:
815 template <> template <> class C<int>::D<int>;
816 template <> template <class U> class C<int>::D; */
818 for (t = DECL_TEMPLATE_INSTANTIATIONS
819 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
820 t; t = TREE_CHAIN (t))
821 if (TREE_VALUE (t) != type
822 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
823 error ("specialization %qT after instantiation %qT",
824 type, TREE_VALUE (t));
826 /* Mark TYPE as a specialization. And as a result, we only
827 have one level of template argument for the innermost
829 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
830 CLASSTYPE_TI_ARGS (type)
831 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
834 else if (processing_specialization)
836 error ("explicit specialization of non-template %qT", type);
837 return error_mark_node;
843 /* Returns nonzero if we can optimize the retrieval of specializations
844 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
845 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
848 optimize_specialization_lookup_p (tree tmpl)
850 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
851 && DECL_CLASS_SCOPE_P (tmpl)
852 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
854 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
855 /* The optimized lookup depends on the fact that the
856 template arguments for the member function template apply
857 purely to the containing class, which is not true if the
858 containing class is an explicit or partial
860 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
861 && !DECL_MEMBER_TEMPLATE_P (tmpl)
862 && !DECL_CONV_FN_P (tmpl)
863 /* It is possible to have a template that is not a member
864 template and is not a member of a template class:
866 template <typename T>
867 struct S { friend A::f(); };
869 Here, the friend function is a template, but the context does
870 not have template information. The optimized lookup relies
871 on having ARGS be the template arguments for both the class
872 and the function template. */
873 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
876 /* Retrieve the specialization (in the sense of [temp.spec] - a
877 specialization is either an instantiation or an explicit
878 specialization) of TMPL for the given template ARGS. If there is
879 no such specialization, return NULL_TREE. The ARGS are a vector of
880 arguments, or a vector of vectors of arguments, in the case of
881 templates with more than one level of parameters.
883 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
884 then we search for a partial specialization matching ARGS. This
885 parameter is ignored if TMPL is not a class template. */
888 retrieve_specialization (tree tmpl, tree args,
889 bool class_specializations_p)
891 if (args == error_mark_node)
894 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
896 /* There should be as many levels of arguments as there are
897 levels of parameters. */
898 gcc_assert (TMPL_ARGS_DEPTH (args)
899 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
901 if (optimize_specialization_lookup_p (tmpl))
904 tree class_specialization;
905 VEC(tree,gc) *methods;
909 /* The template arguments actually apply to the containing
910 class. Find the class specialization with those
912 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
914 = retrieve_specialization (class_template, args,
915 /*class_specializations_p=*/false);
916 if (!class_specialization)
918 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
919 for the specialization. */
920 idx = class_method_index_for_fn (class_specialization, tmpl);
923 /* Iterate through the methods with the indicated name, looking
924 for the one that has an instance of TMPL. */
925 methods = CLASSTYPE_METHOD_VEC (class_specialization);
926 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
928 tree fn = OVL_CURRENT (fns);
929 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
939 /* Class templates store their instantiations on the
940 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
941 DECL_TEMPLATE_SPECIALIZATIONS list. */
942 if (!class_specializations_p
943 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL
944 && TAGGED_TYPE_P (TREE_TYPE (tmpl)))
945 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
947 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
949 /* Iterate through the list until we find a matching template. */
950 while (*sp != NULL_TREE)
954 if (comp_template_args (TREE_PURPOSE (spec), args))
956 /* Use the move-to-front heuristic to speed up future
960 *sp = TREE_CHAIN (*sp);
961 TREE_CHAIN (spec) = *head;
964 return TREE_VALUE (spec);
966 sp = &TREE_CHAIN (spec);
973 /* Like retrieve_specialization, but for local declarations. */
976 retrieve_local_specialization (tree tmpl)
978 tree spec = (tree) htab_find_with_hash (local_specializations, tmpl,
979 htab_hash_pointer (tmpl));
980 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
983 /* Returns nonzero iff DECL is a specialization of TMPL. */
986 is_specialization_of (tree decl, tree tmpl)
990 if (TREE_CODE (decl) == FUNCTION_DECL)
994 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1000 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1002 for (t = TREE_TYPE (decl);
1004 t = CLASSTYPE_USE_TEMPLATE (t)
1005 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1006 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1013 /* Returns nonzero iff DECL is a specialization of friend declaration
1014 FRIEND according to [temp.friend]. */
1017 is_specialization_of_friend (tree decl, tree friend)
1019 bool need_template = true;
1022 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1023 || TREE_CODE (decl) == TYPE_DECL);
1025 /* For [temp.friend/6] when FRIEND is an ordinary member function
1026 of a template class, we want to check if DECL is a specialization
1028 if (TREE_CODE (friend) == FUNCTION_DECL
1029 && DECL_TEMPLATE_INFO (friend)
1030 && !DECL_USE_TEMPLATE (friend))
1032 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1033 friend = DECL_TI_TEMPLATE (friend);
1034 need_template = false;
1036 else if (TREE_CODE (friend) == TEMPLATE_DECL
1037 && !PRIMARY_TEMPLATE_P (friend))
1038 need_template = false;
1040 /* There is nothing to do if this is not a template friend. */
1041 if (TREE_CODE (friend) != TEMPLATE_DECL)
1044 if (is_specialization_of (decl, friend))
1048 A member of a class template may be declared to be a friend of a
1049 non-template class. In this case, the corresponding member of
1050 every specialization of the class template is a friend of the
1051 class granting friendship.
1053 For example, given a template friend declaration
1055 template <class T> friend void A<T>::f();
1057 the member function below is considered a friend
1059 template <> struct A<int> {
1063 For this type of template friend, TEMPLATE_DEPTH below will be
1064 nonzero. To determine if DECL is a friend of FRIEND, we first
1065 check if the enclosing class is a specialization of another. */
1067 template_depth = template_class_depth (DECL_CONTEXT (friend));
1069 && DECL_CLASS_SCOPE_P (decl)
1070 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1071 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
1073 /* Next, we check the members themselves. In order to handle
1074 a few tricky cases, such as when FRIEND's are
1076 template <class T> friend void A<T>::g(T t);
1077 template <class T> template <T t> friend void A<T>::h();
1081 void A<int>::g(int);
1082 template <int> void A<int>::h();
1084 we need to figure out ARGS, the template arguments from
1085 the context of DECL. This is required for template substitution
1086 of `T' in the function parameter of `g' and template parameter
1087 of `h' in the above examples. Here ARGS corresponds to `int'. */
1089 tree context = DECL_CONTEXT (decl);
1090 tree args = NULL_TREE;
1091 int current_depth = 0;
1093 while (current_depth < template_depth)
1095 if (CLASSTYPE_TEMPLATE_INFO (context))
1097 if (current_depth == 0)
1098 args = TYPE_TI_ARGS (context);
1100 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1103 context = TYPE_CONTEXT (context);
1106 if (TREE_CODE (decl) == FUNCTION_DECL)
1111 tree friend_args_type;
1112 tree decl_args_type;
1114 /* Make sure that both DECL and FRIEND are templates or
1116 is_template = DECL_TEMPLATE_INFO (decl)
1117 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1118 if (need_template ^ is_template)
1120 else if (is_template)
1122 /* If both are templates, check template parameter list. */
1124 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1126 if (!comp_template_parms
1127 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1131 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1134 decl_type = TREE_TYPE (decl);
1136 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1137 tf_none, NULL_TREE);
1138 if (friend_type == error_mark_node)
1141 /* Check if return types match. */
1142 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1145 /* Check if function parameter types match, ignoring the
1146 `this' parameter. */
1147 friend_args_type = TYPE_ARG_TYPES (friend_type);
1148 decl_args_type = TYPE_ARG_TYPES (decl_type);
1149 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1150 friend_args_type = TREE_CHAIN (friend_args_type);
1151 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1152 decl_args_type = TREE_CHAIN (decl_args_type);
1154 return compparms (decl_args_type, friend_args_type);
1158 /* DECL is a TYPE_DECL */
1160 tree decl_type = TREE_TYPE (decl);
1162 /* Make sure that both DECL and FRIEND are templates or
1165 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1166 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1168 if (need_template ^ is_template)
1170 else if (is_template)
1173 /* If both are templates, check the name of the two
1174 TEMPLATE_DECL's first because is_friend didn't. */
1175 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1176 != DECL_NAME (friend))
1179 /* Now check template parameter list. */
1181 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1183 return comp_template_parms
1184 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1188 return (DECL_NAME (decl)
1189 == DECL_NAME (friend));
1195 /* Register the specialization SPEC as a specialization of TMPL with
1196 the indicated ARGS. IS_FRIEND indicates whether the specialization
1197 is actually just a friend declaration. Returns SPEC, or an
1198 equivalent prior declaration, if available. */
1201 register_specialization (tree spec, tree tmpl, tree args, bool is_friend)
1205 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1207 if (TREE_CODE (spec) == FUNCTION_DECL
1208 && uses_template_parms (DECL_TI_ARGS (spec)))
1209 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1210 register it; we want the corresponding TEMPLATE_DECL instead.
1211 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1212 the more obvious `uses_template_parms (spec)' to avoid problems
1213 with default function arguments. In particular, given
1214 something like this:
1216 template <class T> void f(T t1, T t = T())
1218 the default argument expression is not substituted for in an
1219 instantiation unless and until it is actually needed. */
1222 fn = retrieve_specialization (tmpl, args,
1223 /*class_specializations_p=*/false);
1224 /* We can sometimes try to re-register a specialization that we've
1225 already got. In particular, regenerate_decl_from_template calls
1226 duplicate_decls which will update the specialization list. But,
1227 we'll still get called again here anyhow. It's more convenient
1228 to simply allow this than to try to prevent it. */
1231 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1233 if (DECL_TEMPLATE_INSTANTIATION (fn))
1236 || DECL_EXPLICIT_INSTANTIATION (fn))
1238 error ("specialization of %qD after instantiation",
1240 return error_mark_node;
1245 /* This situation should occur only if the first
1246 specialization is an implicit instantiation, the
1247 second is an explicit specialization, and the
1248 implicit instantiation has not yet been used. That
1249 situation can occur if we have implicitly
1250 instantiated a member function and then specialized
1253 We can also wind up here if a friend declaration that
1254 looked like an instantiation turns out to be a
1257 template <class T> void foo(T);
1258 class S { friend void foo<>(int) };
1259 template <> void foo(int);
1261 We transform the existing DECL in place so that any
1262 pointers to it become pointers to the updated
1265 If there was a definition for the template, but not
1266 for the specialization, we want this to look as if
1267 there were no definition, and vice versa. */
1268 DECL_INITIAL (fn) = NULL_TREE;
1269 duplicate_decls (spec, fn, is_friend);
1270 /* The call to duplicate_decls will have applied
1273 An explicit specialization of a function template
1274 is inline only if it is explicitly declared to be,
1275 and independently of whether its function template
1278 to the primary function; now copy the inline bits to
1279 the various clones. */
1280 FOR_EACH_CLONE (clone, fn)
1282 DECL_DECLARED_INLINE_P (clone)
1283 = DECL_DECLARED_INLINE_P (fn);
1287 check_specialization_namespace (fn);
1292 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1294 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1295 /* Dup decl failed, but this is a new definition. Set the
1296 line number so any errors match this new
1298 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1304 /* A specialization must be declared in the same namespace as the
1305 template it is specializing. */
1306 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1307 && !check_specialization_namespace (tmpl))
1308 DECL_CONTEXT (spec) = FROB_CONTEXT (decl_namespace_context (tmpl));
1310 if (!optimize_specialization_lookup_p (tmpl))
1311 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1312 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1317 /* Unregister the specialization SPEC as a specialization of TMPL.
1318 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1319 if the SPEC was listed as a specialization of TMPL. */
1322 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1326 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1328 s = &TREE_CHAIN (*s))
1329 if (TREE_VALUE (*s) == spec)
1332 *s = TREE_CHAIN (*s);
1334 TREE_VALUE (*s) = new_spec;
1341 /* Compare an entry in the local specializations hash table P1 (which
1342 is really a pointer to a TREE_LIST) with P2 (which is really a
1346 eq_local_specializations (const void *p1, const void *p2)
1348 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1351 /* Hash P1, an entry in the local specializations table. */
1354 hash_local_specialization (const void* p1)
1356 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1359 /* Like register_specialization, but for local declarations. We are
1360 registering SPEC, an instantiation of TMPL. */
1363 register_local_specialization (tree spec, tree tmpl)
1367 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1368 htab_hash_pointer (tmpl), INSERT);
1369 *slot = build_tree_list (spec, tmpl);
1372 /* TYPE is a class type. Returns true if TYPE is an explicitly
1373 specialized class. */
1376 explicit_class_specialization_p (tree type)
1378 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1380 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1383 /* Print the list of candidate FNS in an error message. */
1386 print_candidates (tree fns)
1390 const char *str = "candidates are:";
1392 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1396 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1397 error ("%s %+#D", str, OVL_CURRENT (f));
1402 /* Returns the template (one of the functions given by TEMPLATE_ID)
1403 which can be specialized to match the indicated DECL with the
1404 explicit template args given in TEMPLATE_ID. The DECL may be
1405 NULL_TREE if none is available. In that case, the functions in
1406 TEMPLATE_ID are non-members.
1408 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1409 specialization of a member template.
1411 The TEMPLATE_COUNT is the number of references to qualifying
1412 template classes that appeared in the name of the function. See
1413 check_explicit_specialization for a more accurate description.
1415 TSK indicates what kind of template declaration (if any) is being
1416 declared. TSK_TEMPLATE indicates that the declaration given by
1417 DECL, though a FUNCTION_DECL, has template parameters, and is
1418 therefore a template function.
1420 The template args (those explicitly specified and those deduced)
1421 are output in a newly created vector *TARGS_OUT.
1423 If it is impossible to determine the result, an error message is
1424 issued. The error_mark_node is returned to indicate failure. */
1427 determine_specialization (tree template_id,
1430 int need_member_template,
1436 tree explicit_targs;
1437 tree candidates = NULL_TREE;
1438 /* A TREE_LIST of templates of which DECL may be a specialization.
1439 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1440 corresponding TREE_PURPOSE is the set of template arguments that,
1441 when used to instantiate the template, would produce a function
1442 with the signature of DECL. */
1443 tree templates = NULL_TREE;
1445 struct cp_binding_level *b;
1447 *targs_out = NULL_TREE;
1449 if (template_id == error_mark_node || decl == error_mark_node)
1450 return error_mark_node;
1452 fns = TREE_OPERAND (template_id, 0);
1453 explicit_targs = TREE_OPERAND (template_id, 1);
1455 if (fns == error_mark_node)
1456 return error_mark_node;
1458 /* Check for baselinks. */
1459 if (BASELINK_P (fns))
1460 fns = BASELINK_FUNCTIONS (fns);
1462 if (!is_overloaded_fn (fns))
1464 error ("%qD is not a function template", fns);
1465 return error_mark_node;
1468 /* Count the number of template headers specified for this
1471 for (b = current_binding_level;
1472 b->kind == sk_template_parms;
1476 for (; fns; fns = OVL_NEXT (fns))
1478 tree fn = OVL_CURRENT (fns);
1480 if (TREE_CODE (fn) == TEMPLATE_DECL)
1482 tree decl_arg_types;
1485 /* In case of explicit specialization, we need to check if
1486 the number of template headers appearing in the specialization
1487 is correct. This is usually done in check_explicit_specialization,
1488 but the check done there cannot be exhaustive when specializing
1489 member functions. Consider the following code:
1491 template <> void A<int>::f(int);
1492 template <> template <> void A<int>::f(int);
1494 Assuming that A<int> is not itself an explicit specialization
1495 already, the first line specializes "f" which is a non-template
1496 member function, whilst the second line specializes "f" which
1497 is a template member function. So both lines are syntactically
1498 correct, and check_explicit_specialization does not reject
1501 Here, we can do better, as we are matching the specialization
1502 against the declarations. We count the number of template
1503 headers, and we check if they match TEMPLATE_COUNT + 1
1504 (TEMPLATE_COUNT is the number of qualifying template classes,
1505 plus there must be another header for the member template
1508 Notice that if header_count is zero, this is not a
1509 specialization but rather a template instantiation, so there
1510 is no check we can perform here. */
1511 if (header_count && header_count != template_count + 1)
1514 /* Check that the number of template arguments at the
1515 innermost level for DECL is the same as for FN. */
1516 if (current_binding_level->kind == sk_template_parms
1517 && !current_binding_level->explicit_spec_p
1518 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1519 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1520 (current_template_parms))))
1523 /* DECL might be a specialization of FN. */
1524 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1525 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1527 /* For a non-static member function, we need to make sure
1528 that the const qualification is the same. Since
1529 get_bindings does not try to merge the "this" parameter,
1530 we must do the comparison explicitly. */
1531 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1532 && !same_type_p (TREE_VALUE (fn_arg_types),
1533 TREE_VALUE (decl_arg_types)))
1536 /* Skip the "this" parameter and, for constructors of
1537 classes with virtual bases, the VTT parameter. A
1538 full specialization of a constructor will have a VTT
1539 parameter, but a template never will. */
1541 = skip_artificial_parms_for (decl, decl_arg_types);
1543 = skip_artificial_parms_for (fn, fn_arg_types);
1545 /* Check that the number of function parameters matches.
1547 template <class T> void f(int i = 0);
1548 template <> void f<int>();
1549 The specialization f<int> is invalid but is not caught
1550 by get_bindings below. */
1551 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1554 /* Function templates cannot be specializations; there are
1555 no partial specializations of functions. Therefore, if
1556 the type of DECL does not match FN, there is no
1558 if (tsk == tsk_template)
1560 if (compparms (fn_arg_types, decl_arg_types))
1561 candidates = tree_cons (NULL_TREE, fn, candidates);
1565 /* See whether this function might be a specialization of this
1567 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1570 /* We cannot deduce template arguments that when used to
1571 specialize TMPL will produce DECL. */
1574 /* Save this template, and the arguments deduced. */
1575 templates = tree_cons (targs, fn, templates);
1577 else if (need_member_template)
1578 /* FN is an ordinary member function, and we need a
1579 specialization of a member template. */
1581 else if (TREE_CODE (fn) != FUNCTION_DECL)
1582 /* We can get IDENTIFIER_NODEs here in certain erroneous
1585 else if (!DECL_FUNCTION_MEMBER_P (fn))
1586 /* This is just an ordinary non-member function. Nothing can
1587 be a specialization of that. */
1589 else if (DECL_ARTIFICIAL (fn))
1590 /* Cannot specialize functions that are created implicitly. */
1594 tree decl_arg_types;
1596 /* This is an ordinary member function. However, since
1597 we're here, we can assume it's enclosing class is a
1598 template class. For example,
1600 template <typename T> struct S { void f(); };
1601 template <> void S<int>::f() {}
1603 Here, S<int>::f is a non-template, but S<int> is a
1604 template class. If FN has the same type as DECL, we
1605 might be in business. */
1607 if (!DECL_TEMPLATE_INFO (fn))
1608 /* Its enclosing class is an explicit specialization
1609 of a template class. This is not a candidate. */
1612 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1613 TREE_TYPE (TREE_TYPE (fn))))
1614 /* The return types differ. */
1617 /* Adjust the type of DECL in case FN is a static member. */
1618 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1619 if (DECL_STATIC_FUNCTION_P (fn)
1620 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1621 decl_arg_types = TREE_CHAIN (decl_arg_types);
1623 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1626 candidates = tree_cons (NULL_TREE, fn, candidates);
1630 if (templates && TREE_CHAIN (templates))
1636 It is possible for a specialization with a given function
1637 signature to be instantiated from more than one function
1638 template. In such cases, explicit specification of the
1639 template arguments must be used to uniquely identify the
1640 function template specialization being specialized.
1642 Note that here, there's no suggestion that we're supposed to
1643 determine which of the candidate templates is most
1644 specialized. However, we, also have:
1648 Partial ordering of overloaded function template
1649 declarations is used in the following contexts to select
1650 the function template to which a function template
1651 specialization refers:
1653 -- when an explicit specialization refers to a function
1656 So, we do use the partial ordering rules, at least for now.
1657 This extension can only serve to make invalid programs valid,
1658 so it's safe. And, there is strong anecdotal evidence that
1659 the committee intended the partial ordering rules to apply;
1660 the EDG front end has that behavior, and John Spicer claims
1661 that the committee simply forgot to delete the wording in
1662 [temp.expl.spec]. */
1663 tree tmpl = most_specialized_instantiation (templates);
1664 if (tmpl != error_mark_node)
1667 TREE_CHAIN (templates) = NULL_TREE;
1671 if (templates == NULL_TREE && candidates == NULL_TREE)
1673 error ("template-id %qD for %q+D does not match any template "
1674 "declaration", template_id, decl);
1675 return error_mark_node;
1677 else if ((templates && TREE_CHAIN (templates))
1678 || (candidates && TREE_CHAIN (candidates))
1679 || (templates && candidates))
1681 error ("ambiguous template specialization %qD for %q+D",
1683 chainon (candidates, templates);
1684 print_candidates (candidates);
1685 return error_mark_node;
1688 /* We have one, and exactly one, match. */
1691 tree fn = TREE_VALUE (candidates);
1692 /* DECL is a re-declaration of a template function. */
1693 if (TREE_CODE (fn) == TEMPLATE_DECL)
1695 /* It was a specialization of an ordinary member function in a
1697 *targs_out = copy_node (DECL_TI_ARGS (fn));
1698 return DECL_TI_TEMPLATE (fn);
1701 /* It was a specialization of a template. */
1702 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1703 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1705 *targs_out = copy_node (targs);
1706 SET_TMPL_ARGS_LEVEL (*targs_out,
1707 TMPL_ARGS_DEPTH (*targs_out),
1708 TREE_PURPOSE (templates));
1711 *targs_out = TREE_PURPOSE (templates);
1712 return TREE_VALUE (templates);
1715 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1716 but with the default argument values filled in from those in the
1720 copy_default_args_to_explicit_spec_1 (tree spec_types,
1723 tree new_spec_types;
1728 if (spec_types == void_list_node)
1729 return void_list_node;
1731 /* Substitute into the rest of the list. */
1733 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1734 TREE_CHAIN (tmpl_types));
1736 /* Add the default argument for this parameter. */
1737 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1738 TREE_VALUE (spec_types),
1742 /* DECL is an explicit specialization. Replicate default arguments
1743 from the template it specializes. (That way, code like:
1745 template <class T> void f(T = 3);
1746 template <> void f(double);
1749 works, as required.) An alternative approach would be to look up
1750 the correct default arguments at the call-site, but this approach
1751 is consistent with how implicit instantiations are handled. */
1754 copy_default_args_to_explicit_spec (tree decl)
1759 tree new_spec_types;
1763 tree object_type = NULL_TREE;
1764 tree in_charge = NULL_TREE;
1765 tree vtt = NULL_TREE;
1767 /* See if there's anything we need to do. */
1768 tmpl = DECL_TI_TEMPLATE (decl);
1769 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1770 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1771 if (TREE_PURPOSE (t))
1776 old_type = TREE_TYPE (decl);
1777 spec_types = TYPE_ARG_TYPES (old_type);
1779 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1781 /* Remove the this pointer, but remember the object's type for
1783 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1784 spec_types = TREE_CHAIN (spec_types);
1785 tmpl_types = TREE_CHAIN (tmpl_types);
1787 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1789 /* DECL may contain more parameters than TMPL due to the extra
1790 in-charge parameter in constructors and destructors. */
1791 in_charge = spec_types;
1792 spec_types = TREE_CHAIN (spec_types);
1794 if (DECL_HAS_VTT_PARM_P (decl))
1797 spec_types = TREE_CHAIN (spec_types);
1801 /* Compute the merged default arguments. */
1803 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1805 /* Compute the new FUNCTION_TYPE. */
1809 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1814 /* Put the in-charge parameter back. */
1815 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1816 TREE_VALUE (in_charge),
1819 new_type = build_method_type_directly (object_type,
1820 TREE_TYPE (old_type),
1824 new_type = build_function_type (TREE_TYPE (old_type),
1826 new_type = cp_build_type_attribute_variant (new_type,
1827 TYPE_ATTRIBUTES (old_type));
1828 new_type = build_exception_variant (new_type,
1829 TYPE_RAISES_EXCEPTIONS (old_type));
1830 TREE_TYPE (decl) = new_type;
1833 /* Check to see if the function just declared, as indicated in
1834 DECLARATOR, and in DECL, is a specialization of a function
1835 template. We may also discover that the declaration is an explicit
1836 instantiation at this point.
1838 Returns DECL, or an equivalent declaration that should be used
1839 instead if all goes well. Issues an error message if something is
1840 amiss. Returns error_mark_node if the error is not easily
1843 FLAGS is a bitmask consisting of the following flags:
1845 2: The function has a definition.
1846 4: The function is a friend.
1848 The TEMPLATE_COUNT is the number of references to qualifying
1849 template classes that appeared in the name of the function. For
1852 template <class T> struct S { void f(); };
1855 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1856 classes are not counted in the TEMPLATE_COUNT, so that in
1858 template <class T> struct S {};
1859 template <> struct S<int> { void f(); }
1860 template <> void S<int>::f();
1862 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1863 invalid; there should be no template <>.)
1865 If the function is a specialization, it is marked as such via
1866 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1867 is set up correctly, and it is added to the list of specializations
1868 for that template. */
1871 check_explicit_specialization (tree declarator,
1876 int have_def = flags & 2;
1877 int is_friend = flags & 4;
1878 int specialization = 0;
1879 int explicit_instantiation = 0;
1880 int member_specialization = 0;
1881 tree ctype = DECL_CLASS_CONTEXT (decl);
1882 tree dname = DECL_NAME (decl);
1887 if (!processing_specialization)
1890 tsk = tsk_excessive_parms;
1893 tsk = current_tmpl_spec_kind (template_count);
1898 if (processing_specialization)
1901 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1903 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1906 /* This could be something like:
1908 template <class T> void f(T);
1909 class S { friend void f<>(int); } */
1913 /* This case handles bogus declarations like template <>
1914 template <class T> void f<int>(); */
1916 error ("template-id %qD in declaration of primary template",
1923 case tsk_invalid_member_spec:
1924 /* The error has already been reported in
1925 check_specialization_scope. */
1926 return error_mark_node;
1928 case tsk_invalid_expl_inst:
1929 error ("template parameter list used in explicit instantiation");
1935 error ("definition provided for explicit instantiation");
1937 explicit_instantiation = 1;
1940 case tsk_excessive_parms:
1941 case tsk_insufficient_parms:
1942 if (tsk == tsk_excessive_parms)
1943 error ("too many template parameter lists in declaration of %qD",
1945 else if (template_header_count)
1946 error("too few template parameter lists in declaration of %qD", decl);
1948 error("explicit specialization of %qD must be introduced by "
1949 "%<template <>%>", decl);
1953 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1955 member_specialization = 1;
1961 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1963 /* This case handles bogus declarations like template <>
1964 template <class T> void f<int>(); */
1966 if (uses_template_parms (declarator))
1967 error ("function template partial specialization %qD "
1968 "is not allowed", declarator);
1970 error ("template-id %qD in declaration of primary template",
1975 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1976 /* This is a specialization of a member template, without
1977 specialization the containing class. Something like:
1979 template <class T> struct S {
1980 template <class U> void f (U);
1982 template <> template <class U> void S<int>::f(U) {}
1984 That's a specialization -- but of the entire template. */
1992 if (specialization || member_specialization)
1994 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1995 for (; t; t = TREE_CHAIN (t))
1996 if (TREE_PURPOSE (t))
1999 ("default argument specified in explicit specialization");
2004 if (specialization || member_specialization || explicit_instantiation)
2006 tree tmpl = NULL_TREE;
2007 tree targs = NULL_TREE;
2009 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2010 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2014 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2019 /* If there is no class context, the explicit instantiation
2020 must be at namespace scope. */
2021 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2023 /* Find the namespace binding, using the declaration
2025 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2027 if (fns == error_mark_node || !is_overloaded_fn (fns))
2029 error ("%qD is not a template function", dname);
2030 fns = error_mark_node;
2034 tree fn = OVL_CURRENT (fns);
2035 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2036 CP_DECL_CONTEXT (fn)))
2037 error ("%qD is not declared in %qD",
2038 decl, current_namespace);
2042 declarator = lookup_template_function (fns, NULL_TREE);
2045 if (declarator == error_mark_node)
2046 return error_mark_node;
2048 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2050 if (!explicit_instantiation)
2051 /* A specialization in class scope. This is invalid,
2052 but the error will already have been flagged by
2053 check_specialization_scope. */
2054 return error_mark_node;
2057 /* It's not valid to write an explicit instantiation in
2060 class C { template void f(); }
2062 This case is caught by the parser. However, on
2065 template class C { void f(); };
2067 (which is invalid) we can get here. The error will be
2074 else if (ctype != NULL_TREE
2075 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2078 /* Find the list of functions in ctype that have the same
2079 name as the declared function. */
2080 tree name = TREE_OPERAND (declarator, 0);
2081 tree fns = NULL_TREE;
2084 if (constructor_name_p (name, ctype))
2086 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2088 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
2089 : !CLASSTYPE_DESTRUCTORS (ctype))
2091 /* From [temp.expl.spec]:
2093 If such an explicit specialization for the member
2094 of a class template names an implicitly-declared
2095 special member function (clause _special_), the
2096 program is ill-formed.
2098 Similar language is found in [temp.explicit]. */
2099 error ("specialization of implicitly-declared special member function");
2100 return error_mark_node;
2103 name = is_constructor ? ctor_identifier : dtor_identifier;
2106 if (!DECL_CONV_FN_P (decl))
2108 idx = lookup_fnfields_1 (ctype, name);
2110 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2114 VEC(tree,gc) *methods;
2117 /* For a type-conversion operator, we cannot do a
2118 name-based lookup. We might be looking for `operator
2119 int' which will be a specialization of `operator T'.
2120 So, we find *all* the conversion operators, and then
2121 select from them. */
2124 methods = CLASSTYPE_METHOD_VEC (ctype);
2126 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2127 VEC_iterate (tree, methods, idx, ovl);
2130 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2131 /* There are no more conversion functions. */
2134 /* Glue all these conversion functions together
2135 with those we already have. */
2136 for (; ovl; ovl = OVL_NEXT (ovl))
2137 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2141 if (fns == NULL_TREE)
2143 error ("no member function %qD declared in %qT", name, ctype);
2144 return error_mark_node;
2147 TREE_OPERAND (declarator, 0) = fns;
2150 /* Figure out what exactly is being specialized at this point.
2151 Note that for an explicit instantiation, even one for a
2152 member function, we cannot tell apriori whether the
2153 instantiation is for a member template, or just a member
2154 function of a template class. Even if a member template is
2155 being instantiated, the member template arguments may be
2156 elided if they can be deduced from the rest of the
2158 tmpl = determine_specialization (declarator, decl,
2160 member_specialization,
2164 if (!tmpl || tmpl == error_mark_node)
2165 /* We couldn't figure out what this declaration was
2167 return error_mark_node;
2170 tree gen_tmpl = most_general_template (tmpl);
2172 if (explicit_instantiation)
2174 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2175 is done by do_decl_instantiation later. */
2177 int arg_depth = TMPL_ARGS_DEPTH (targs);
2178 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2180 if (arg_depth > parm_depth)
2182 /* If TMPL is not the most general template (for
2183 example, if TMPL is a friend template that is
2184 injected into namespace scope), then there will
2185 be too many levels of TARGS. Remove some of them
2190 new_targs = make_tree_vec (parm_depth);
2191 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2192 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2193 = TREE_VEC_ELT (targs, i);
2197 return instantiate_template (tmpl, targs, tf_error);
2200 /* If we thought that the DECL was a member function, but it
2201 turns out to be specializing a static member function,
2202 make DECL a static member function as well. */
2203 if (DECL_STATIC_FUNCTION_P (tmpl)
2204 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2205 revert_static_member_fn (decl);
2207 /* If this is a specialization of a member template of a
2208 template class, we want to return the TEMPLATE_DECL, not
2209 the specialization of it. */
2210 if (tsk == tsk_template)
2212 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2213 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2216 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2217 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2218 = DECL_SOURCE_LOCATION (decl);
2219 /* We want to use the argument list specified in the
2220 definition, not in the original declaration. */
2221 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2222 = DECL_ARGUMENTS (decl);
2227 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2228 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2230 /* Inherit default function arguments from the template
2231 DECL is specializing. */
2232 copy_default_args_to_explicit_spec (decl);
2234 /* This specialization has the same protection as the
2235 template it specializes. */
2236 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2237 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2239 /* 7.1.1-1 [dcl.stc]
2241 A storage-class-specifier shall not be specified in an
2242 explicit specialization...
2244 The parser rejects these, so unless action is taken here,
2245 explicit function specializations will always appear with
2248 The action recommended by the C++ CWG in response to C++
2249 defect report 605 is to make the storage class and linkage
2250 of the explicit specialization match the templated function:
2252 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2254 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2256 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2257 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2259 /* This specialization has the same linkage and visibility as
2260 the function template it specializes. */
2261 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2262 if (! TREE_PUBLIC (decl))
2264 DECL_INTERFACE_KNOWN (decl) = 1;
2265 DECL_NOT_REALLY_EXTERN (decl) = 1;
2267 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2268 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2270 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2271 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2275 /* If DECL is a friend declaration, declared using an
2276 unqualified name, the namespace associated with DECL may
2277 have been set incorrectly. For example, in:
2279 template <typename T> void f(T);
2281 struct S { friend void f<int>(int); }
2284 we will have set the DECL_CONTEXT for the friend
2285 declaration to N, rather than to the global namespace. */
2286 if (DECL_NAMESPACE_SCOPE_P (decl))
2287 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2289 if (is_friend && !have_def)
2290 /* This is not really a declaration of a specialization.
2291 It's just the name of an instantiation. But, it's not
2292 a request for an instantiation, either. */
2293 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2294 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2295 /* This is indeed a specialization. In case of constructors
2296 and destructors, we need in-charge and not-in-charge
2297 versions in V3 ABI. */
2298 clone_function_decl (decl, /*update_method_vec_p=*/0);
2300 /* Register this specialization so that we can find it
2302 decl = register_specialization (decl, gen_tmpl, targs, is_friend);
2309 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2310 parameters. These are represented in the same format used for
2311 DECL_TEMPLATE_PARMS. */
2314 comp_template_parms (const_tree parms1, const_tree parms2)
2319 if (parms1 == parms2)
2322 for (p1 = parms1, p2 = parms2;
2323 p1 != NULL_TREE && p2 != NULL_TREE;
2324 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2326 tree t1 = TREE_VALUE (p1);
2327 tree t2 = TREE_VALUE (p2);
2330 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2331 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2333 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2336 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2338 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2339 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2341 /* If either of the template parameters are invalid, assume
2342 they match for the sake of error recovery. */
2343 if (parm1 == error_mark_node || parm2 == error_mark_node)
2346 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2349 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2350 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2351 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2353 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2358 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2359 /* One set of parameters has more parameters lists than the
2366 /* Determine whether PARM is a parameter pack. */
2368 template_parameter_pack_p (const_tree parm)
2370 /* Determine if we have a non-type template parameter pack. */
2371 if (TREE_CODE (parm) == PARM_DECL)
2372 return (DECL_TEMPLATE_PARM_P (parm)
2373 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2375 /* If this is a list of template parameters, we could get a
2376 TYPE_DECL or a TEMPLATE_DECL. */
2377 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2378 parm = TREE_TYPE (parm);
2380 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2381 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2382 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2385 /* Determine whether ARGS describes a variadic template args list,
2386 i.e., one that is terminated by a template argument pack. */
2388 template_args_variadic_p (tree args)
2393 if (args == NULL_TREE)
2396 args = INNERMOST_TEMPLATE_ARGS (args);
2397 nargs = TREE_VEC_LENGTH (args);
2402 last_parm = TREE_VEC_ELT (args, nargs - 1);
2404 return ARGUMENT_PACK_P (last_parm);
2407 /* Generate a new name for the parameter pack name NAME (an
2408 IDENTIFIER_NODE) that incorporates its */
2410 make_ith_pack_parameter_name (tree name, int i)
2412 /* Munge the name to include the parameter index. */
2416 sprintf(numbuf, "%i", i);
2417 newname = (char*)alloca (IDENTIFIER_LENGTH (name) + strlen(numbuf) + 2);
2418 sprintf(newname, "%s#%i", IDENTIFIER_POINTER (name), i);
2419 return get_identifier (newname);
2422 /* Structure used to track the progress of find_parameter_packs_r. */
2423 struct find_parameter_pack_data
2425 /* TREE_LIST that will contain all of the parameter packs found by
2427 tree* parameter_packs;
2429 /* Set of AST nodes that have been visited by the traversal. */
2430 struct pointer_set_t *visited;
2432 /* Whether we should replace parameter packs with
2433 ERROR_MARK_NODE. Used by check_for_bare_parameter_packs. */
2434 bool set_packs_to_error;
2437 /* Identifies all of the argument packs that occur in a template
2438 argument and appends them to the TREE_LIST inside DATA, which is a
2439 find_parameter_pack_data structure. This is a subroutine of
2440 make_pack_expansion and uses_parameter_packs. */
2442 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2445 struct find_parameter_pack_data* ppd =
2446 (struct find_parameter_pack_data*)data;
2447 bool parameter_pack_p = false;
2449 /* Don't visit nodes twice, except when we're clearing out parameter
2451 if (pointer_set_contains (ppd->visited, *tp))
2458 /* Identify whether this is a parameter pack or not. */
2459 switch (TREE_CODE (t))
2461 case TEMPLATE_PARM_INDEX:
2462 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2463 parameter_pack_p = true;
2466 case TEMPLATE_TYPE_PARM:
2467 case TEMPLATE_TEMPLATE_PARM:
2468 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2469 parameter_pack_p = true;
2473 if (FUNCTION_PARAMETER_PACK_P (t))
2475 /* We don't want to walk into the type of a PARM_DECL,
2476 because we don't want to see the type parameter pack. */
2478 parameter_pack_p = true;
2483 if (ppd->set_packs_to_error)
2484 /* Pointer types are shared, set in that case the outermost
2485 POINTER_TYPE to error_mark_node rather than the parameter pack. */
2493 /* Not a parameter pack. */
2497 if (parameter_pack_p)
2499 /* Add this parameter pack to the list. */
2500 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2502 if (ppd->set_packs_to_error)
2503 /* The caller requested that we set the parameter packs to
2504 ERROR_MARK_NODE so that they will not trip up the compiler
2505 later. The caller is responsible for emitting an error. */
2506 *tp = error_mark_node;
2508 /* Make sure we do not visit this node again. */
2509 pointer_set_insert (ppd->visited, *tp);
2512 /* Make sure we do not visit this node again. */
2513 pointer_set_insert (ppd->visited, *tp);
2516 cp_walk_tree (&TYPE_CONTEXT (t),
2517 &find_parameter_packs_r, ppd, NULL);
2519 /* This switch statement will return immediately if we don't find a
2521 switch (TREE_CODE (t))
2523 case TEMPLATE_PARM_INDEX:
2526 case BOUND_TEMPLATE_TEMPLATE_PARM:
2527 /* Check the template itself. */
2528 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2529 &find_parameter_packs_r, ppd, NULL);
2530 /* Check the template arguments. */
2531 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2536 case TEMPLATE_TYPE_PARM:
2537 case TEMPLATE_TEMPLATE_PARM:
2544 if (TYPE_PTRMEMFUNC_P (t))
2550 if (TYPE_TEMPLATE_INFO (t))
2551 cp_walk_tree (&TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
2552 &find_parameter_packs_r, ppd, NULL);
2558 cp_walk_tree (&TREE_TYPE (t),
2559 &find_parameter_packs_r, ppd, NULL);
2563 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
2568 case TYPE_PACK_EXPANSION:
2569 case EXPR_PACK_EXPANSION:
2574 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
2586 /* Determines if the expression or type T uses any parameter packs. */
2588 uses_parameter_packs (tree t)
2590 tree parameter_packs = NULL_TREE;
2591 struct find_parameter_pack_data ppd;
2592 ppd.parameter_packs = ¶meter_packs;
2593 ppd.visited = pointer_set_create ();
2594 ppd.set_packs_to_error = false;
2595 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, NULL);
2596 pointer_set_destroy (ppd.visited);
2597 return parameter_packs != NULL_TREE;
2600 /* Turn ARG, which may be an expression, type, or a TREE_LIST
2601 representation a base-class initializer into a parameter pack
2602 expansion. If all goes well, the resulting node will be an
2603 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
2606 make_pack_expansion (tree arg)
2609 tree parameter_packs = NULL_TREE;
2610 bool for_types = false;
2611 struct find_parameter_pack_data ppd;
2613 ppd.set_packs_to_error = false;
2615 if (!arg || arg == error_mark_node)
2618 if (TREE_CODE (arg) == TREE_LIST)
2620 /* The only time we will see a TREE_LIST here is for a base
2621 class initializer. In this case, the TREE_PURPOSE will be a
2622 _TYPE node (representing the base class expansion we're
2623 initializing) and the TREE_VALUE will be a TREE_LIST
2624 containing the initialization arguments.
2626 The resulting expansion looks somewhat different from most
2627 expansions. Rather than returning just one _EXPANSION, we
2628 return a TREE_LIST whose TREE_PURPOSE is a
2629 TYPE_PACK_EXPANSION containing the bases that will be
2630 initialized. The TREE_VALUE will be identical to the
2631 original TREE_VALUE, which is a list of arguments that will
2632 be passed to each base. We do not introduce any new pack
2633 expansion nodes into the TREE_VALUE (although it is possible
2634 that some already exist), because the TREE_PURPOSE and
2635 TREE_VALUE all need to be expanded together with the same
2636 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
2637 resulting TREE_PURPOSE will mention the parameter packs in
2638 both the bases and the arguments to the bases. */
2641 tree parameter_packs = NULL_TREE;
2643 /* Determine which parameter packs will be used by the base
2645 ppd.visited = pointer_set_create ();
2646 ppd.parameter_packs = ¶meter_packs;
2647 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
2650 if (parameter_packs == NULL_TREE)
2652 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
2653 pointer_set_destroy (ppd.visited);
2654 return error_mark_node;
2657 if (TREE_VALUE (arg) != void_type_node)
2659 /* Collect the sets of parameter packs used in each of the
2660 initialization arguments. */
2661 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
2663 /* Determine which parameter packs will be expanded in this
2665 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
2670 pointer_set_destroy (ppd.visited);
2672 /* Create the pack expansion type for the base type. */
2673 purpose = make_node (TYPE_PACK_EXPANSION);
2674 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
2675 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
2677 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2678 they will rarely be compared to anything. */
2679 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
2681 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
2684 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
2687 /* Build the PACK_EXPANSION_* node. */
2688 result = make_node (for_types ? TYPE_PACK_EXPANSION : EXPR_PACK_EXPANSION);
2689 SET_PACK_EXPANSION_PATTERN (result, arg);
2690 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
2692 /* Propagate type and const-expression information. */
2693 TREE_TYPE (result) = TREE_TYPE (arg);
2694 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
2697 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2698 they will rarely be compared to anything. */
2699 SET_TYPE_STRUCTURAL_EQUALITY (result);
2701 /* Determine which parameter packs will be expanded. */
2702 ppd.parameter_packs = ¶meter_packs;
2703 ppd.visited = pointer_set_create ();
2704 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, NULL);
2705 pointer_set_destroy (ppd.visited);
2707 /* Make sure we found some parameter packs. */
2708 if (parameter_packs == NULL_TREE)
2711 error ("expansion pattern %<%T%> contains no argument packs", arg);
2713 error ("expansion pattern %<%E%> contains no argument packs", arg);
2714 return error_mark_node;
2716 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
2721 /* Checks T for any "bare" parameter packs, which have not yet been
2722 expanded, and issues an error if any are found. This operation can
2723 only be done on full expressions or types (e.g., an expression
2724 statement, "if" condition, etc.), because we could have expressions like:
2726 foo(f(g(h(args)))...)
2728 where "args" is a parameter pack. check_for_bare_parameter_packs
2729 should not be called for the subexpressions args, h(args),
2730 g(h(args)), or f(g(h(args))), because we would produce erroneous
2733 Returns TRUE if there were no bare parameter packs, returns FALSE
2734 (and emits an error) if there were bare parameter packs.*/
2736 check_for_bare_parameter_packs (tree* t)
2738 tree parameter_packs = NULL_TREE;
2739 struct find_parameter_pack_data ppd;
2741 if (!processing_template_decl || !t || !*t || *t == error_mark_node)
2744 if (TREE_CODE (*t) == TYPE_DECL)
2745 t = &TREE_TYPE (*t);
2747 ppd.parameter_packs = ¶meter_packs;
2748 ppd.visited = pointer_set_create ();
2749 ppd.set_packs_to_error = false;
2750 cp_walk_tree (t, &find_parameter_packs_r, &ppd, NULL);
2751 pointer_set_destroy (ppd.visited);
2753 if (parameter_packs)
2755 error ("parameter packs not expanded with `...':");
2756 while (parameter_packs)
2758 tree pack = TREE_VALUE (parameter_packs);
2759 tree name = NULL_TREE;
2761 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
2762 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
2763 name = TYPE_NAME (pack);
2764 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
2765 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
2767 name = DECL_NAME (pack);
2770 inform (" %qD", name);
2772 inform (" <anonymous>");
2774 parameter_packs = TREE_CHAIN (parameter_packs);
2777 /* Clean up any references to these parameter packs within the
2779 ppd.parameter_packs = ¶meter_packs;
2780 ppd.visited = pointer_set_create ();
2781 ppd.set_packs_to_error = true;
2782 cp_walk_tree (t, &find_parameter_packs_r, &ppd, NULL);
2783 pointer_set_destroy (ppd.visited);
2791 /* Expand any parameter packs that occur in the template arguments in
2794 expand_template_argument_pack (tree args)
2796 tree result_args = NULL_TREE;
2797 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
2798 int num_result_args = -1;
2800 /* First, determine if we need to expand anything, and the number of
2801 slots we'll need. */
2802 for (in_arg = 0; in_arg < nargs; ++in_arg)
2804 tree arg = TREE_VEC_ELT (args, in_arg);
2805 if (ARGUMENT_PACK_P (arg))
2807 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
2808 if (num_result_args < 0)
2809 num_result_args = in_arg + num_packed;
2811 num_result_args += num_packed;
2815 if (num_result_args >= 0)
2820 /* If no expansion is necessary, we're done. */
2821 if (num_result_args < 0)
2824 /* Expand arguments. */
2825 result_args = make_tree_vec (num_result_args);
2826 for (in_arg = 0; in_arg < nargs; ++in_arg)
2828 tree arg = TREE_VEC_ELT (args, in_arg);
2829 if (ARGUMENT_PACK_P (arg))
2831 tree packed = ARGUMENT_PACK_ARGS (arg);
2832 int i, num_packed = TREE_VEC_LENGTH (packed);
2833 for (i = 0; i < num_packed; ++i, ++out_arg)
2834 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
2838 TREE_VEC_ELT (result_args, out_arg) = arg;
2846 /* Complain if DECL shadows a template parameter.
2848 [temp.local]: A template-parameter shall not be redeclared within its
2849 scope (including nested scopes). */
2852 check_template_shadow (tree decl)
2856 /* If we're not in a template, we can't possibly shadow a template
2858 if (!current_template_parms)
2861 /* Figure out what we're shadowing. */
2862 if (TREE_CODE (decl) == OVERLOAD)
2863 decl = OVL_CURRENT (decl);
2864 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2866 /* If there's no previous binding for this name, we're not shadowing
2867 anything, let alone a template parameter. */
2871 /* If we're not shadowing a template parameter, we're done. Note
2872 that OLDDECL might be an OVERLOAD (or perhaps even an
2873 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2875 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2878 /* We check for decl != olddecl to avoid bogus errors for using a
2879 name inside a class. We check TPFI to avoid duplicate errors for
2880 inline member templates. */
2882 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2885 error ("declaration of %q+#D", decl);
2886 error (" shadows template parm %q+#D", olddecl);
2889 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2890 ORIG_LEVEL, DECL, and TYPE. */
2893 build_template_parm_index (int index,
2899 tree t = make_node (TEMPLATE_PARM_INDEX);
2900 TEMPLATE_PARM_IDX (t) = index;
2901 TEMPLATE_PARM_LEVEL (t) = level;
2902 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2903 TEMPLATE_PARM_DECL (t) = decl;
2904 TREE_TYPE (t) = type;
2905 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2906 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2907 TREE_READONLY (t) = TREE_READONLY (decl);
2912 /* Find the canonical type parameter for the given template type
2913 parameter. Returns the canonical type parameter, which may be TYPE
2914 if no such parameter existed. */
2916 canonical_type_parameter (tree type)
2919 int idx = TEMPLATE_TYPE_IDX (type);
2920 if (!canonical_template_parms)
2921 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
2923 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
2924 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
2926 list = VEC_index (tree, canonical_template_parms, idx);
2927 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
2928 list = TREE_CHAIN (list);
2931 return TREE_VALUE (list);
2934 VEC_replace(tree, canonical_template_parms, idx,
2935 tree_cons (NULL_TREE, type,
2936 VEC_index (tree, canonical_template_parms, idx)));
2941 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2942 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2943 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2944 new one is created. */
2947 reduce_template_parm_level (tree index, tree type, int levels, tree args,
2948 tsubst_flags_t complain)
2950 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2951 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2952 != TEMPLATE_PARM_LEVEL (index) - levels))
2954 tree orig_decl = TEMPLATE_PARM_DECL (index);
2957 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2958 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2959 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2960 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2961 DECL_ARTIFICIAL (decl) = 1;
2962 SET_DECL_TEMPLATE_PARM_P (decl);
2964 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2965 TEMPLATE_PARM_LEVEL (index) - levels,
2966 TEMPLATE_PARM_ORIG_LEVEL (index),
2968 TEMPLATE_PARM_DESCENDANTS (index) = t;
2969 TEMPLATE_PARM_PARAMETER_PACK (t)
2970 = TEMPLATE_PARM_PARAMETER_PACK (index);
2972 /* Template template parameters need this. */
2973 if (TREE_CODE (decl) == TEMPLATE_DECL)
2974 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
2975 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
2979 return TEMPLATE_PARM_DESCENDANTS (index);
2982 /* Process information from new template parameter PARM and append it to the
2983 LIST being built. This new parameter is a non-type parameter iff
2984 IS_NON_TYPE is true. This new parameter is a parameter
2985 pack iff IS_PARAMETER_PACK is true. */
2988 process_template_parm (tree list, tree parm, bool is_non_type,
2989 bool is_parameter_pack)
2996 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2997 defval = TREE_PURPOSE (parm);
3001 tree p = tree_last (list);
3003 if (p && TREE_VALUE (p) != error_mark_node)
3006 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3007 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3009 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3019 parm = TREE_VALUE (parm);
3021 SET_DECL_TEMPLATE_PARM_P (parm);
3023 if (TREE_TYPE (parm) == error_mark_node)
3025 err_parm_list = build_tree_list (defval, parm);
3026 TREE_VALUE (err_parm_list) = error_mark_node;
3027 return chainon (list, err_parm_list);
3033 The top-level cv-qualifiers on the template-parameter are
3034 ignored when determining its type. */
3035 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3036 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3038 err_parm_list = build_tree_list (defval, parm);
3039 TREE_VALUE (err_parm_list) = error_mark_node;
3040 return chainon (list, err_parm_list);
3043 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3045 /* This template parameter is not a parameter pack, but it
3046 should be. Complain about "bare" parameter packs. */
3047 check_for_bare_parameter_packs (&TREE_TYPE (parm));
3049 /* Recover by calling this a parameter pack. */
3050 is_parameter_pack = true;
3054 /* A template parameter is not modifiable. */
3055 TREE_CONSTANT (parm) = 1;
3056 TREE_INVARIANT (parm) = 1;
3057 TREE_READONLY (parm) = 1;
3058 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3059 TREE_CONSTANT (decl) = 1;
3060 TREE_INVARIANT (decl) = 1;
3061 TREE_READONLY (decl) = 1;
3062 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3063 = build_template_parm_index (idx, processing_template_decl,
3064 processing_template_decl,
3065 decl, TREE_TYPE (parm));
3067 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3068 = is_parameter_pack;
3073 parm = TREE_VALUE (TREE_VALUE (parm));
3075 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3077 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
3078 /* This is for distinguishing between real templates and template
3079 template parameters */
3080 TREE_TYPE (parm) = t;
3081 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3086 t = make_aggr_type (TEMPLATE_TYPE_PARM);
3087 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3088 decl = build_decl (TYPE_DECL, parm, t);
3091 TYPE_NAME (t) = decl;
3092 TYPE_STUB_DECL (t) = decl;
3094 TEMPLATE_TYPE_PARM_INDEX (t)
3095 = build_template_parm_index (idx, processing_template_decl,
3096 processing_template_decl,
3097 decl, TREE_TYPE (parm));
3098 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3099 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3101 DECL_ARTIFICIAL (decl) = 1;
3102 SET_DECL_TEMPLATE_PARM_P (decl);
3104 parm = build_tree_list (defval, parm);
3105 return chainon (list, parm);
3108 /* The end of a template parameter list has been reached. Process the
3109 tree list into a parameter vector, converting each parameter into a more
3110 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3114 end_template_parm_list (tree parms)
3118 tree saved_parmlist = make_tree_vec (list_length (parms));
3120 current_template_parms
3121 = tree_cons (size_int (processing_template_decl),
3122 saved_parmlist, current_template_parms);
3124 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3126 next = TREE_CHAIN (parm);
3127 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3128 TREE_CHAIN (parm) = NULL_TREE;
3131 --processing_template_parmlist;
3133 return saved_parmlist;
3136 /* end_template_decl is called after a template declaration is seen. */
3139 end_template_decl (void)
3141 reset_specialization ();
3143 if (! processing_template_decl)
3146 /* This matches the pushlevel in begin_template_parm_list. */
3149 --processing_template_decl;
3150 current_template_parms = TREE_CHAIN (current_template_parms);
3153 /* Within the declaration of a template, return all levels of template
3154 parameters that apply. The template parameters are represented as
3155 a TREE_VEC, in the form documented in cp-tree.h for template
3159 current_template_args (void)
3162 tree args = NULL_TREE;
3163 int length = TMPL_PARMS_DEPTH (current_template_parms);
3166 /* If there is only one level of template parameters, we do not
3167 create a TREE_VEC of TREE_VECs. Instead, we return a single
3168 TREE_VEC containing the arguments. */
3170 args = make_tree_vec (length);
3172 for (header = current_template_parms; header; header = TREE_CHAIN (header))
3174 tree a = copy_node (TREE_VALUE (header));
3177 TREE_TYPE (a) = NULL_TREE;
3178 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3180 tree t = TREE_VEC_ELT (a, i);
3182 /* T will be a list if we are called from within a
3183 begin/end_template_parm_list pair, but a vector directly
3184 if within a begin/end_member_template_processing pair. */
3185 if (TREE_CODE (t) == TREE_LIST)
3189 if (t != error_mark_node)
3191 if (TREE_CODE (t) == TYPE_DECL
3192 || TREE_CODE (t) == TEMPLATE_DECL)
3196 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3198 /* Turn this argument into a TYPE_ARGUMENT_PACK
3199 with a single element, which expands T. */
3200 tree vec = make_tree_vec (1);
3201 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3203 t = make_node (TYPE_ARGUMENT_PACK);
3204 SET_ARGUMENT_PACK_ARGS (t, vec);
3209 t = DECL_INITIAL (t);
3211 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3213 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3214 with a single element, which expands T. */
3215 tree vec = make_tree_vec (1);
3216 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3217 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3219 t = make_node (NONTYPE_ARGUMENT_PACK);
3220 SET_ARGUMENT_PACK_ARGS (t, vec);
3221 TREE_TYPE (t) = type;
3224 TREE_VEC_ELT (a, i) = t;
3230 TREE_VEC_ELT (args, --l) = a;
3238 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3239 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3240 a member template. Used by push_template_decl below. */
3243 build_template_decl (tree decl, tree parms, bool member_template_p)
3245 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3246 DECL_TEMPLATE_PARMS (tmpl) = parms;
3247 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3248 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3249 if (DECL_LANG_SPECIFIC (decl))
3251 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
3252 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
3253 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
3254 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
3255 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
3256 if (DECL_OVERLOADED_OPERATOR_P (decl))
3257 SET_OVERLOADED_OPERATOR_CODE (tmpl,
3258 DECL_OVERLOADED_OPERATOR_P (decl));
3264 struct template_parm_data
3266 /* The level of the template parameters we are currently
3270 /* The index of the specialization argument we are currently
3274 /* An array whose size is the number of template parameters. The
3275 elements are nonzero if the parameter has been used in any one
3276 of the arguments processed so far. */
3279 /* An array whose size is the number of template arguments. The
3280 elements are nonzero if the argument makes use of template
3281 parameters of this level. */
3282 int* arg_uses_template_parms;
3285 /* Subroutine of push_template_decl used to see if each template
3286 parameter in a partial specialization is used in the explicit
3287 argument list. If T is of the LEVEL given in DATA (which is
3288 treated as a template_parm_data*), then DATA->PARMS is marked
3292 mark_template_parm (tree t, void* data)
3296 struct template_parm_data* tpd = (struct template_parm_data*) data;
3298 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3300 level = TEMPLATE_PARM_LEVEL (t);
3301 idx = TEMPLATE_PARM_IDX (t);
3305 level = TEMPLATE_TYPE_LEVEL (t);
3306 idx = TEMPLATE_TYPE_IDX (t);
3309 if (level == tpd->level)
3311 tpd->parms[idx] = 1;
3312 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
3315 /* Return zero so that for_each_template_parm will continue the
3316 traversal of the tree; we want to mark *every* template parm. */
3320 /* Process the partial specialization DECL. */
3323 process_partial_specialization (tree decl)
3325 tree type = TREE_TYPE (decl);
3326 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
3327 tree specargs = CLASSTYPE_TI_ARGS (type);
3328 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
3329 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3330 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
3331 int nargs = TREE_VEC_LENGTH (inner_args);
3332 int ntparms = TREE_VEC_LENGTH (inner_parms);
3334 int did_error_intro = 0;
3335 struct template_parm_data tpd;
3336 struct template_parm_data tpd2;
3338 /* We check that each of the template parameters given in the
3339 partial specialization is used in the argument list to the
3340 specialization. For example:
3342 template <class T> struct S;
3343 template <class T> struct S<T*>;
3345 The second declaration is OK because `T*' uses the template
3346 parameter T, whereas
3348 template <class T> struct S<int>;
3350 is no good. Even trickier is:
3361 The S2<T> declaration is actually invalid; it is a
3362 full-specialization. Of course,
3365 struct S2<T (*)(U)>;
3367 or some such would have been OK. */
3368 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
3369 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
3370 memset (tpd.parms, 0, sizeof (int) * ntparms);
3372 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
3373 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
3374 for (i = 0; i < nargs; ++i)
3376 tpd.current_arg = i;
3377 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
3378 &mark_template_parm,
3382 for (i = 0; i < ntparms; ++i)
3383 if (tpd.parms[i] == 0)
3385 /* One of the template parms was not used in the
3387 if (!did_error_intro)
3389 error ("template parameters not used in partial specialization:");
3390 did_error_intro = 1;
3393 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
3396 /* [temp.class.spec]
3398 The argument list of the specialization shall not be identical to
3399 the implicit argument list of the primary template. */
3400 if (comp_template_args
3402 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
3404 error ("partial specialization %qT does not specialize any template arguments", type);
3406 /* [temp.class.spec]
3408 A partially specialized non-type argument expression shall not
3409 involve template parameters of the partial specialization except
3410 when the argument expression is a simple identifier.
3412 The type of a template parameter corresponding to a specialized
3413 non-type argument shall not be dependent on a parameter of the
3416 Also, we verify that pack expansions only occur at the
3417 end of the argument list. */
3418 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
3420 for (i = 0; i < nargs; ++i)
3422 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
3423 tree arg = TREE_VEC_ELT (inner_args, i);
3424 tree packed_args = NULL_TREE;
3427 if (ARGUMENT_PACK_P (arg))
3429 /* Extract the arguments from the argument pack. We'll be
3430 iterating over these in the following loop. */
3431 packed_args = ARGUMENT_PACK_ARGS (arg);
3432 len = TREE_VEC_LENGTH (packed_args);
3435 for (j = 0; j < len; j++)
3438 /* Get the Jth argument in the parameter pack. */
3439 arg = TREE_VEC_ELT (packed_args, j);
3441 if (PACK_EXPANSION_P (arg))
3443 /* Pack expansions must come at the end of the
3445 if ((packed_args && j < len - 1)
3446 || (!packed_args && i < nargs - 1))
3448 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3449 error ("parameter pack argument %qE must be at the end of the template argument list", arg);
3451 error ("parameter pack argument %qT must be at the end of the template argument list", arg);
3454 TREE_VEC_ELT (packed_args, j) = error_mark_node;
3458 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3459 /* We only care about the pattern. */
3460 arg = PACK_EXPANSION_PATTERN (arg);
3462 if (/* These first two lines are the `non-type' bit. */
3464 && TREE_CODE (arg) != TEMPLATE_DECL
3465 /* This next line is the `argument expression is not just a
3466 simple identifier' condition and also the `specialized
3467 non-type argument' bit. */
3468 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
3470 if ((!packed_args && tpd.arg_uses_template_parms[i])
3471 || (packed_args && uses_template_parms (arg)))
3472 error ("template argument %qE involves template parameter(s)",
3476 /* Look at the corresponding template parameter,
3477 marking which template parameters its type depends
3479 tree type = TREE_TYPE (parm);
3483 /* We haven't yet initialized TPD2. Do so now. */
3484 tpd2.arg_uses_template_parms
3485 = (int *) alloca (sizeof (int) * nargs);
3486 /* The number of parameters here is the number in the
3487 main template, which, as checked in the assertion
3489 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
3491 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
3494 /* Mark the template parameters. But this time, we're
3495 looking for the template parameters of the main
3496 template, not in the specialization. */
3497 tpd2.current_arg = i;
3498 tpd2.arg_uses_template_parms[i] = 0;
3499 memset (tpd2.parms, 0, sizeof (int) * nargs);
3500 for_each_template_parm (type,
3501 &mark_template_parm,
3505 if (tpd2.arg_uses_template_parms [i])
3507 /* The type depended on some template parameters.
3508 If they are fully specialized in the
3509 specialization, that's OK. */
3511 for (j = 0; j < nargs; ++j)
3512 if (tpd2.parms[j] != 0
3513 && tpd.arg_uses_template_parms [j])
3515 error ("type %qT of template argument %qE depends "
3516 "on template parameter(s)",
3527 if (retrieve_specialization (maintmpl, specargs,
3528 /*class_specializations_p=*/true))
3529 /* We've already got this specialization. */
3532 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
3533 = tree_cons (specargs, inner_parms,
3534 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
3535 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
3539 /* Check that a template declaration's use of default arguments is not
3540 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
3541 nonzero if DECL is the thing declared by a primary template.
3542 IS_PARTIAL is nonzero if DECL is a partial specialization.
3545 IS_FRIEND_DECL is nonzero if DECL is a friend function template
3546 declaration (but not a definition); 1 indicates a declaration, 2
3547 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
3548 emitted for extraneous default arguments.
3550 Returns TRUE if there were no errors found, FALSE otherwise. */
3553 check_default_tmpl_args (tree decl, tree parms, int is_primary,
3554 int is_partial, int is_friend_decl)
3557 int last_level_to_check;
3559 bool no_errors = true;
3563 A default template-argument shall not be specified in a
3564 function template declaration or a function template definition, nor
3565 in the template-parameter-list of the definition of a member of a
3568 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
3569 /* You can't have a function template declaration in a local
3570 scope, nor you can you define a member of a class template in a
3574 if (current_class_type
3575 && !TYPE_BEING_DEFINED (current_class_type)
3576 && DECL_LANG_SPECIFIC (decl)
3577 /* If this is either a friend defined in the scope of the class
3578 or a member function. */
3579 && (DECL_FUNCTION_MEMBER_P (decl)
3580 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
3581 : DECL_FRIEND_CONTEXT (decl)
3582 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
3584 /* And, if it was a member function, it really was defined in
3585 the scope of the class. */
3586 && (!DECL_FUNCTION_MEMBER_P (decl)
3587 || DECL_INITIALIZED_IN_CLASS_P (decl)))
3588 /* We already checked these parameters when the template was
3589 declared, so there's no need to do it again now. This function
3590 was defined in class scope, but we're processing it's body now
3591 that the class is complete. */
3594 /* Core issue 226 (C++0x only): the following only applies to class
3596 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
3600 If a template-parameter has a default template-argument, all
3601 subsequent template-parameters shall have a default
3602 template-argument supplied. */
3603 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
3605 tree inner_parms = TREE_VALUE (parm_level);
3606 int ntparms = TREE_VEC_LENGTH (inner_parms);
3607 int seen_def_arg_p = 0;
3610 for (i = 0; i < ntparms; ++i)
3612 tree parm = TREE_VEC_ELT (inner_parms, i);
3614 if (parm == error_mark_node)
3617 if (TREE_PURPOSE (parm))
3619 else if (seen_def_arg_p)
3621 error ("no default argument for %qD", TREE_VALUE (parm));
3622 /* For better subsequent error-recovery, we indicate that
3623 there should have been a default argument. */
3624 TREE_PURPOSE (parm) = error_mark_node;
3631 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
3635 /* For an ordinary class template, default template arguments are
3636 allowed at the innermost level, e.g.:
3637 template <class T = int>
3639 but, in a partial specialization, they're not allowed even
3640 there, as we have in [temp.class.spec]:
3642 The template parameter list of a specialization shall not
3643 contain default template argument values.
3645 So, for a partial specialization, or for a function template
3646 (in C++98/C++03), we look at all of them. */
3649 /* But, for a primary class template that is not a partial
3650 specialization we look at all template parameters except the
3652 parms = TREE_CHAIN (parms);
3654 /* Figure out what error message to issue. */
3655 if (is_friend_decl == 2)
3656 msg = "default template arguments may not be used in function template friend re-declaration";
3657 else if (is_friend_decl)
3658 msg = "default template arguments may not be used in function template friend declarations";
3659 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
3660 msg = "default template arguments may not be used in function templates";
3661 else if (is_partial)
3662 msg = "default template arguments may not be used in partial specializations";
3664 msg = "default argument for template parameter for class enclosing %qD";
3666 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
3667 /* If we're inside a class definition, there's no need to
3668 examine the parameters to the class itself. On the one
3669 hand, they will be checked when the class is defined, and,
3670 on the other, default arguments are valid in things like:
3671 template <class T = double>
3672 struct S { template <class U> void f(U); };
3673 Here the default argument for `S' has no bearing on the
3674 declaration of `f'. */
3675 last_level_to_check = template_class_depth (current_class_type) + 1;
3677 /* Check everything. */
3678 last_level_to_check = 0;
3680 for (parm_level = parms;
3681 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
3682 parm_level = TREE_CHAIN (parm_level))
3684 tree inner_parms = TREE_VALUE (parm_level);
3688 ntparms = TREE_VEC_LENGTH (inner_parms);
3689 for (i = 0; i < ntparms; ++i)
3691 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
3694 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
3699 if (is_friend_decl == 2)
3706 /* Clear out the default argument so that we are not
3708 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
3712 /* At this point, if we're still interested in issuing messages,
3713 they must apply to classes surrounding the object declared. */
3715 msg = "default argument for template parameter for class enclosing %qD";
3721 /* Worker for push_template_decl_real, called via
3722 for_each_template_parm. DATA is really an int, indicating the
3723 level of the parameters we are interested in. If T is a template
3724 parameter of that level, return nonzero. */
3727 template_parm_this_level_p (tree t, void* data)
3729 int this_level = *(int *)data;
3732 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3733 level = TEMPLATE_PARM_LEVEL (t);
3735 level = TEMPLATE_TYPE_LEVEL (t);
3736 return level == this_level;
3739 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
3740 parameters given by current_template_args, or reuses a
3741 previously existing one, if appropriate. Returns the DECL, or an
3742 equivalent one, if it is replaced via a call to duplicate_decls.
3744 If IS_FRIEND is true, DECL is a friend declaration. */
3747 push_template_decl_real (tree decl, bool is_friend)
3755 int new_template_p = 0;
3756 /* True if the template is a member template, in the sense of
3758 bool member_template_p = false;
3760 if (decl == error_mark_node)
3763 /* See if this is a partial specialization. */
3764 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
3765 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3766 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
3768 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
3772 /* For a friend, we want the context of the friend function, not
3773 the type of which it is a friend. */
3774 ctx = DECL_CONTEXT (decl);
3775 else if (CP_DECL_CONTEXT (decl)
3776 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
3777 /* In the case of a virtual function, we want the class in which
3779 ctx = CP_DECL_CONTEXT (decl);
3781 /* Otherwise, if we're currently defining some class, the DECL
3782 is assumed to be a member of the class. */
3783 ctx = current_scope ();
3785 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
3788 if (!DECL_CONTEXT (decl))
3789 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
3791 /* See if this is a primary template. */
3792 if (is_friend && ctx)
3793 /* A friend template that specifies a class context, i.e.
3794 template <typename T> friend void A<T>::f();
3798 primary = template_parm_scope_p ();
3802 if (DECL_CLASS_SCOPE_P (decl))
3803 member_template_p = true;
3804 if (TREE_CODE (decl) == TYPE_DECL
3805 && ANON_AGGRNAME_P (DECL_NAME (decl)))
3806 error ("template class without a name");
3807 else if (TREE_CODE (decl) == FUNCTION_DECL)
3809 if (DECL_DESTRUCTOR_P (decl))
3813 A destructor shall not be a member template. */
3814 error ("destructor %qD declared as member template", decl);
3815 return error_mark_node;
3817 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
3818 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
3819 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
3820 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
3821 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
3822 == void_list_node)))
3824 /* [basic.stc.dynamic.allocation]
3826 An allocation function can be a function
3827 template. ... Template allocation functions shall
3828 have two or more parameters. */
3829 error ("invalid template declaration of %qD", decl);
3830 return error_mark_node;
3833 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3834 && CLASS_TYPE_P (TREE_TYPE (decl)))
3838 error ("template declaration of %q#D", decl);
3839 return error_mark_node;
3843 /* Check to see that the rules regarding the use of default
3844 arguments are not being violated. */
3845 check_default_tmpl_args (decl, current_template_parms,
3846 primary, is_partial, /*is_friend_decl=*/0);
3848 /* Ensure that there are no parameter packs in the type of this
3849 declaration that have not been expanded. */
3850 if (TREE_CODE (decl) == FUNCTION_DECL)
3852 /* Check each of the arguments individually to see if there are
3853 any bare parameter packs. */
3854 tree type = TREE_TYPE (decl);
3855 tree arg = DECL_ARGUMENTS (decl);
3856 tree argtype = TYPE_ARG_TYPES (type);
3858 while (arg && argtype)
3860 if (!FUNCTION_PARAMETER_PACK_P (arg)
3861 && !check_for_bare_parameter_packs (&TREE_TYPE (arg)))
3863 /* This is a PARM_DECL that contains unexpanded parameter
3864 packs. We have already complained about this in the
3865 check_for_bare_parameter_packs call, so just replace
3866 these types with ERROR_MARK_NODE. */
3867 TREE_TYPE (arg) = error_mark_node;
3868 TREE_VALUE (argtype) = error_mark_node;
3871 arg = TREE_CHAIN (arg);
3872 argtype = TREE_CHAIN (argtype);
3875 /* Check for bare parameter packs in the return type and the
3876 exception specifiers. */
3877 if (!check_for_bare_parameter_packs (&TREE_TYPE (type)))
3878 /* Errors were already issued, set return type to int
3879 as the frontend doesn't expect error_mark_node as
3881 TREE_TYPE (type) = integer_type_node;
3882 check_for_bare_parameter_packs (&TYPE_RAISES_EXCEPTIONS (type));
3884 else if (!check_for_bare_parameter_packs (&TREE_TYPE (decl)))
3885 return error_mark_node;
3888 return process_partial_specialization (decl);
3890 /* A primary class template can only have one parameter pack, at the
3891 end of the template parameter list. */
3892 if (primary && TREE_CODE (decl) == TYPE_DECL)
3895 = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3896 int i, len = TREE_VEC_LENGTH (inner_parms);
3897 for (i = 0; i < len - 1; i++)
3899 tree parm = TREE_VALUE (TREE_VEC_ELT (inner_parms, i));
3901 if (template_parameter_pack_p (parm))
3903 if (TREE_CODE (parm) == PARM_DECL)
3904 error ("parameter pack %qE must be at the end of the"
3905 " template parameter list", parm);
3907 error ("parameter pack %qT must be at the end of the"
3908 " template parameter list", TREE_TYPE (parm));
3910 TREE_VALUE (TREE_VEC_ELT (inner_parms, i)) = error_mark_node;
3915 args = current_template_args ();
3918 || TREE_CODE (ctx) == FUNCTION_DECL
3919 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3920 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3922 if (DECL_LANG_SPECIFIC (decl)
3923 && DECL_TEMPLATE_INFO (decl)
3924 && DECL_TI_TEMPLATE (decl))
3925 tmpl = DECL_TI_TEMPLATE (decl);
3926 /* If DECL is a TYPE_DECL for a class-template, then there won't
3927 be DECL_LANG_SPECIFIC. The information equivalent to
3928 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3929 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3930 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3931 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3933 /* Since a template declaration already existed for this
3934 class-type, we must be redeclaring it here. Make sure
3935 that the redeclaration is valid. */
3936 redeclare_class_template (TREE_TYPE (decl),
3937 current_template_parms);
3938 /* We don't need to create a new TEMPLATE_DECL; just use the
3939 one we already had. */
3940 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3944 tmpl = build_template_decl (decl, current_template_parms,
3948 if (DECL_LANG_SPECIFIC (decl)
3949 && DECL_TEMPLATE_SPECIALIZATION (decl))
3951 /* A specialization of a member template of a template
3953 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3954 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3955 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3961 tree a, t, current, parms;
3963 tree tinfo = get_template_info (decl);
3967 error ("template definition of non-template %q#D", decl);
3971 tmpl = TI_TEMPLATE (tinfo);
3973 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3974 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3975 && DECL_TEMPLATE_SPECIALIZATION (decl)
3976 && DECL_MEMBER_TEMPLATE_P (tmpl))
3980 /* The declaration is a specialization of a member
3981 template, declared outside the class. Therefore, the
3982 innermost template arguments will be NULL, so we
3983 replace them with the arguments determined by the
3984 earlier call to check_explicit_specialization. */
3985 args = DECL_TI_ARGS (decl);
3988 = build_template_decl (decl, current_template_parms,
3990 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3991 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3992 DECL_TI_TEMPLATE (decl) = new_tmpl;
3993 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3994 DECL_TEMPLATE_INFO (new_tmpl)
3995 = tree_cons (tmpl, args, NULL_TREE);
3997 register_specialization (new_tmpl,
3998 most_general_template (tmpl),
4004 /* Make sure the template headers we got make sense. */
4006 parms = DECL_TEMPLATE_PARMS (tmpl);
4007 i = TMPL_PARMS_DEPTH (parms);
4008 if (TMPL_ARGS_DEPTH (args) != i)
4010 error ("expected %d levels of template parms for %q#D, got %d",
4011 i, decl, TMPL_ARGS_DEPTH (args));
4014 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4016 a = TMPL_ARGS_LEVEL (args, i);
4017 t = INNERMOST_TEMPLATE_PARMS (parms);
4019 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4021 if (current == decl)
4022 error ("got %d template parameters for %q#D",
4023 TREE_VEC_LENGTH (a), decl);
4025 error ("got %d template parameters for %q#T",
4026 TREE_VEC_LENGTH (a), current);
4027 error (" but %d required", TREE_VEC_LENGTH (t));
4028 return error_mark_node;
4031 if (current == decl)
4034 current = (TYPE_P (current)
4035 ? TYPE_CONTEXT (current)
4036 : DECL_CONTEXT (current));
4039 /* Check that the parms are used in the appropriate qualifying scopes
4040 in the declarator. */
4041 if (!comp_template_args
4043 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4046 template arguments to %qD do not match original template %qD",
4047 decl, DECL_TEMPLATE_RESULT (tmpl));
4048 if (!uses_template_parms (TI_ARGS (tinfo)))
4049 inform ("use template<> for an explicit specialization");
4050 /* Avoid crash in import_export_decl. */
4051 DECL_INTERFACE_KNOWN (decl) = 1;
4052 return error_mark_node;
4056 DECL_TEMPLATE_RESULT (tmpl) = decl;
4057 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4059 /* Push template declarations for global functions and types. Note
4060 that we do not try to push a global template friend declared in a
4061 template class; such a thing may well depend on the template
4062 parameters of the class. */
4063 if (new_template_p && !ctx
4064 && !(is_friend && template_class_depth (current_class_type) > 0))
4066 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4067 if (tmpl == error_mark_node)
4068 return error_mark_node;
4070 /* Hide template friend classes that haven't been declared yet. */
4071 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4073 DECL_ANTICIPATED (tmpl) = 1;
4074 DECL_FRIEND_P (tmpl) = 1;
4080 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4083 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4084 if (DECL_CONV_FN_P (tmpl))
4086 int depth = TMPL_PARMS_DEPTH (parms);
4088 /* It is a conversion operator. See if the type converted to
4089 depends on innermost template operands. */
4091 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4093 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4096 /* Give template template parms a DECL_CONTEXT of the template
4097 for which they are a parameter. */
4098 parms = INNERMOST_TEMPLATE_PARMS (parms);
4099 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4101 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4102 if (TREE_CODE (parm) == TEMPLATE_DECL)
4103 DECL_CONTEXT (parm) = tmpl;
4107 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4108 back to its most general template. If TMPL is a specialization,
4109 ARGS may only have the innermost set of arguments. Add the missing
4110 argument levels if necessary. */
4111 if (DECL_TEMPLATE_INFO (tmpl))
4112 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4114 info = tree_cons (tmpl, args, NULL_TREE);
4116 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4117 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4118 else if (DECL_LANG_SPECIFIC (decl))
4119 DECL_TEMPLATE_INFO (decl) = info;
4121 return DECL_TEMPLATE_RESULT (tmpl);
4125 push_template_decl (tree decl)
4127 return push_template_decl_real (decl, false);
4130 /* Called when a class template TYPE is redeclared with the indicated
4131 template PARMS, e.g.:
4133 template <class T> struct S;
4134 template <class T> struct S {}; */
4137 redeclare_class_template (tree type, tree parms)
4143 if (!TYPE_TEMPLATE_INFO (type))
4145 error ("%qT is not a template type", type);
4149 tmpl = TYPE_TI_TEMPLATE (type);
4150 if (!PRIMARY_TEMPLATE_P (tmpl))
4151 /* The type is nested in some template class. Nothing to worry
4152 about here; there are no new template parameters for the nested
4158 error ("template specifiers not specified in declaration of %qD",
4163 parms = INNERMOST_TEMPLATE_PARMS (parms);
4164 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4166 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4168 error ("redeclared with %d template parameter(s)",
4169 TREE_VEC_LENGTH (parms));
4170 inform ("previous declaration %q+D used %d template parameter(s)",
4171 tmpl, TREE_VEC_LENGTH (tmpl_parms));
4175 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4182 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4183 || TREE_VEC_ELT (parms, i) == error_mark_node)
4186 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4187 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4188 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4189 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4191 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
4193 if (tmpl_parm != error_mark_node
4194 && (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
4195 || (TREE_CODE (tmpl_parm) != TYPE_DECL
4196 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))))
4198 error ("template parameter %q+#D", tmpl_parm);
4199 error ("redeclared here as %q#D", parm);
4203 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
4205 /* We have in [temp.param]:
4207 A template-parameter may not be given default arguments
4208 by two different declarations in the same scope. */
4209 error ("redefinition of default argument for %q#D", parm);
4210 inform ("%Joriginal definition appeared here", tmpl_parm);
4214 if (parm_default != NULL_TREE)
4215 /* Update the previous template parameters (which are the ones
4216 that will really count) with the new default value. */
4217 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
4218 else if (tmpl_default != NULL_TREE)
4219 /* Update the new parameters, too; they'll be used as the
4220 parameters for any members. */
4221 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
4227 /* Simplify EXPR if it is a non-dependent expression. Returns the
4228 (possibly simplified) expression. */
4231 fold_non_dependent_expr (tree expr)
4233 if (expr == NULL_TREE)
4236 /* If we're in a template, but EXPR isn't value dependent, simplify
4237 it. We're supposed to treat:
4239 template <typename T> void f(T[1 + 1]);
4240 template <typename T> void f(T[2]);
4242 as two declarations of the same function, for example. */
4243 if (processing_template_decl
4244 && !type_dependent_expression_p (expr)
4245 && !value_dependent_expression_p (expr))
4247 HOST_WIDE_INT saved_processing_template_decl;
4249 saved_processing_template_decl = processing_template_decl;
4250 processing_template_decl = 0;
4251 expr = tsubst_copy_and_build (expr,
4254 /*in_decl=*/NULL_TREE,
4255 /*function_p=*/false,
4256 /*integral_constant_expression_p=*/true);
4257 processing_template_decl = saved_processing_template_decl;
4262 /* EXPR is an expression which is used in a constant-expression context.
4263 For instance, it could be a VAR_DECL with a constant initializer.
4264 Extract the innest constant expression.
4266 This is basically a more powerful version of
4267 integral_constant_value, which can be used also in templates where
4268 initializers can maintain a syntactic rather than semantic form
4269 (even if they are non-dependent, for access-checking purposes). */
4272 fold_decl_constant_value (tree expr)
4274 tree const_expr = expr;
4277 expr = fold_non_dependent_expr (const_expr);
4278 const_expr = integral_constant_value (expr);
4280 while (expr != const_expr);
4285 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
4286 must be a function or a pointer-to-function type, as specified
4287 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
4288 and check that the resulting function has external linkage. */
4291 convert_nontype_argument_function (tree type, tree expr)
4296 fn = instantiate_type (type, fns, tf_none);
4297 if (fn == error_mark_node)
4298 return error_mark_node;
4301 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
4302 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
4303 if (TREE_CODE (fn_no_ptr) == BASELINK)
4304 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
4306 /* [temp.arg.nontype]/1
4308 A template-argument for a non-type, non-template template-parameter
4311 -- the address of an object or function with external linkage. */
4312 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
4314 error ("%qE is not a valid template argument for type %qT "
4315 "because function %qD has not external linkage",
4316 expr, type, fn_no_ptr);
4323 /* Attempt to convert the non-type template parameter EXPR to the
4324 indicated TYPE. If the conversion is successful, return the
4325 converted value. If the conversion is unsuccessful, return
4326 NULL_TREE if we issued an error message, or error_mark_node if we
4327 did not. We issue error messages for out-and-out bad template
4328 parameters, but not simply because the conversion failed, since we
4329 might be just trying to do argument deduction. Both TYPE and EXPR
4330 must be non-dependent.
4332 The conversion follows the special rules described in
4333 [temp.arg.nontype], and it is much more strict than an implicit
4336 This function is called twice for each template argument (see
4337 lookup_template_class for a more accurate description of this
4338 problem). This means that we need to handle expressions which
4339 are not valid in a C++ source, but can be created from the
4340 first call (for instance, casts to perform conversions). These
4341 hacks can go away after we fix the double coercion problem. */
4344 convert_nontype_argument (tree type, tree expr)
4348 /* Detect immediately string literals as invalid non-type argument.
4349 This special-case is not needed for correctness (we would easily
4350 catch this later), but only to provide better diagnostic for this
4351 common user mistake. As suggested by DR 100, we do not mention
4352 linkage issues in the diagnostic as this is not the point. */
4353 if (TREE_CODE (expr) == STRING_CST)
4355 error ("%qE is not a valid template argument for type %qT "
4356 "because string literals can never be used in this context",
4361 /* If we are in a template, EXPR may be non-dependent, but still
4362 have a syntactic, rather than semantic, form. For example, EXPR
4363 might be a SCOPE_REF, rather than the VAR_DECL to which the
4364 SCOPE_REF refers. Preserving the qualifying scope is necessary
4365 so that access checking can be performed when the template is
4366 instantiated -- but here we need the resolved form so that we can
4367 convert the argument. */
4368 expr = fold_non_dependent_expr (expr);
4369 if (error_operand_p (expr))
4370 return error_mark_node;
4371 expr_type = TREE_TYPE (expr);
4373 /* HACK: Due to double coercion, we can get a
4374 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
4375 which is the tree that we built on the first call (see
4376 below when coercing to reference to object or to reference to
4377 function). We just strip everything and get to the arg.
4378 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
4380 if (TREE_CODE (expr) == NOP_EXPR)
4382 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
4384 /* ??? Maybe we could use convert_from_reference here, but we
4385 would need to relax its constraints because the NOP_EXPR
4386 could actually change the type to something more cv-qualified,
4387 and this is not folded by convert_from_reference. */
4388 tree addr = TREE_OPERAND (expr, 0);
4389 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
4390 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
4391 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
4392 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4393 (TREE_TYPE (expr_type),
4394 TREE_TYPE (TREE_TYPE (addr))));
4396 expr = TREE_OPERAND (addr, 0);
4397 expr_type = TREE_TYPE (expr);
4400 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
4401 parameter is a pointer to object, through decay and
4402 qualification conversion. Let's strip everything. */
4403 else if (TYPE_PTROBV_P (type))
4406 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
4407 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
4408 /* Skip the ADDR_EXPR only if it is part of the decay for
4409 an array. Otherwise, it is part of the original argument
4410 in the source code. */
4411 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
4412 expr = TREE_OPERAND (expr, 0);
4413 expr_type = TREE_TYPE (expr);
4417 /* [temp.arg.nontype]/5, bullet 1
4419 For a non-type template-parameter of integral or enumeration type,
4420 integral promotions (_conv.prom_) and integral conversions
4421 (_conv.integral_) are applied. */
4422 if (INTEGRAL_TYPE_P (type))
4424 if (!INTEGRAL_TYPE_P (expr_type))
4425 return error_mark_node;
4427 expr = fold_decl_constant_value (expr);
4428 /* Notice that there are constant expressions like '4 % 0' which
4429 do not fold into integer constants. */
4430 if (TREE_CODE (expr) != INTEGER_CST)
4432 error ("%qE is not a valid template argument for type %qT "
4433 "because it is a non-constant expression", expr, type);
4437 /* At this point, an implicit conversion does what we want,
4438 because we already know that the expression is of integral
4440 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
4441 if (expr == error_mark_node)
4442 return error_mark_node;
4444 /* Conversion was allowed: fold it to a bare integer constant. */
4447 /* [temp.arg.nontype]/5, bullet 2
4449 For a non-type template-parameter of type pointer to object,
4450 qualification conversions (_conv.qual_) and the array-to-pointer
4451 conversion (_conv.array_) are applied. */
4452 else if (TYPE_PTROBV_P (type))
4454 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
4456 A template-argument for a non-type, non-template template-parameter
4457 shall be one of: [...]
4459 -- the name of a non-type template-parameter;
4460 -- the address of an object or function with external linkage, [...]
4461 expressed as "& id-expression" where the & is optional if the name
4462 refers to a function or array, or if the corresponding
4463 template-parameter is a reference.
4465 Here, we do not care about functions, as they are invalid anyway
4466 for a parameter of type pointer-to-object. */
4468 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
4469 /* Non-type template parameters are OK. */
4471 else if (TREE_CODE (expr) != ADDR_EXPR
4472 && TREE_CODE (expr_type) != ARRAY_TYPE)
4474 if (TREE_CODE (expr) == VAR_DECL)
4476 error ("%qD is not a valid template argument "
4477 "because %qD is a variable, not the address of "
4482 /* Other values, like integer constants, might be valid
4483 non-type arguments of some other type. */
4484 return error_mark_node;
4490 decl = ((TREE_CODE (expr) == ADDR_EXPR)
4491 ? TREE_OPERAND (expr, 0) : expr);
4492 if (TREE_CODE (decl) != VAR_DECL)
4494 error ("%qE is not a valid template argument of type %qT "
4495 "because %qE is not a variable",
4499 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
4501 error ("%qE is not a valid template argument of type %qT "
4502 "because %qD does not have external linkage",
4508 expr = decay_conversion (expr);
4509 if (expr == error_mark_node)
4510 return error_mark_node;
4512 expr = perform_qualification_conversions (type, expr);
4513 if (expr == error_mark_node)
4514 return error_mark_node;
4516 /* [temp.arg.nontype]/5, bullet 3
4518 For a non-type template-parameter of type reference to object, no
4519 conversions apply. The type referred to by the reference may be more
4520 cv-qualified than the (otherwise identical) type of the
4521 template-argument. The template-parameter is bound directly to the
4522 template-argument, which must be an lvalue. */
4523 else if (TYPE_REF_OBJ_P (type))
4525 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
4527 return error_mark_node;
4529 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
4531 error ("%qE is not a valid template argument for type %qT "
4532 "because of conflicts in cv-qualification", expr, type);
4536 if (!real_lvalue_p (expr))
4538 error ("%qE is not a valid template argument for type %qT "
4539 "because it is not an lvalue", expr, type);
4543 /* [temp.arg.nontype]/1
4545 A template-argument for a non-type, non-template template-parameter
4546 shall be one of: [...]
4548 -- the address of an object or function with external linkage. */
4549 if (!DECL_EXTERNAL_LINKAGE_P (expr))
4551 error ("%qE is not a valid template argument for type %qT "
4552 "because object %qD has not external linkage",
4557 expr = build_nop (type, build_address (expr));
4559 /* [temp.arg.nontype]/5, bullet 4
4561 For a non-type template-parameter of type pointer to function, only
4562 the function-to-pointer conversion (_conv.func_) is applied. If the
4563 template-argument represents a set of overloaded functions (or a
4564 pointer to such), the matching function is selected from the set
4566 else if (TYPE_PTRFN_P (type))
4568 /* If the argument is a template-id, we might not have enough
4569 context information to decay the pointer. */
4570 if (!type_unknown_p (expr_type))
4572 expr = decay_conversion (expr);
4573 if (expr == error_mark_node)
4574 return error_mark_node;
4577 expr = convert_nontype_argument_function (type, expr);
4578 if (!expr || expr == error_mark_node)
4581 /* [temp.arg.nontype]/5, bullet 5
4583 For a non-type template-parameter of type reference to function, no
4584 conversions apply. If the template-argument represents a set of
4585 overloaded functions, the matching function is selected from the set
4587 else if (TYPE_REFFN_P (type))
4589 if (TREE_CODE (expr) == ADDR_EXPR)
4591 error ("%qE is not a valid template argument for type %qT "
4592 "because it is a pointer", expr, type);
4593 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
4597 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
4598 if (!expr || expr == error_mark_node)
4601 expr = build_nop (type, build_address (expr));
4603 /* [temp.arg.nontype]/5, bullet 6
4605 For a non-type template-parameter of type pointer to member function,
4606 no conversions apply. If the template-argument represents a set of
4607 overloaded member functions, the matching member function is selected
4608 from the set (_over.over_). */
4609 else if (TYPE_PTRMEMFUNC_P (type))
4611 expr = instantiate_type (type, expr, tf_none);
4612 if (expr == error_mark_node)
4613 return error_mark_node;
4615 /* There is no way to disable standard conversions in
4616 resolve_address_of_overloaded_function (called by
4617 instantiate_type). It is possible that the call succeeded by
4618 converting &B::I to &D::I (where B is a base of D), so we need
4619 to reject this conversion here.
4621 Actually, even if there was a way to disable standard conversions,
4622 it would still be better to reject them here so that we can
4623 provide a superior diagnostic. */
4624 if (!same_type_p (TREE_TYPE (expr), type))
4626 /* Make sure we are just one standard conversion off. */
4627 gcc_assert (can_convert (type, TREE_TYPE (expr)));
4628 error ("%qE is not a valid template argument for type %qT "
4629 "because it is of type %qT", expr, type,
4631 inform ("standard conversions are not allowed in this context");
4635 /* [temp.arg.nontype]/5, bullet 7
4637 For a non-type template-parameter of type pointer to data member,
4638 qualification conversions (_conv.qual_) are applied. */
4639 else if (TYPE_PTRMEM_P (type))
4641 expr = perform_qualification_conversions (type, expr);
4642 if (expr == error_mark_node)
4645 /* A template non-type parameter must be one of the above. */
4649 /* Sanity check: did we actually convert the argument to the
4651 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
4656 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
4657 template template parameters. Both PARM_PARMS and ARG_PARMS are
4658 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
4661 Consider the example:
4662 template <class T> class A;
4663 template<template <class U> class TT> class B;
4665 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
4666 the parameters to A, and OUTER_ARGS contains A. */
4669 coerce_template_template_parms (tree parm_parms,
4671 tsubst_flags_t complain,
4675 int nparms, nargs, i;
4678 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
4679 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
4681 nparms = TREE_VEC_LENGTH (parm_parms);
4682 nargs = TREE_VEC_LENGTH (arg_parms);
4684 if (nargs != nparms)
4687 for (i = 0; i < nparms; ++i)
4689 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
4690 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
4693 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
4694 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
4696 if (arg == NULL_TREE || arg == error_mark_node
4697 || parm == NULL_TREE || parm == error_mark_node)
4700 if (TREE_CODE (arg) != TREE_CODE (parm))
4703 switch (TREE_CODE (parm))
4706 /* We encounter instantiations of templates like
4707 template <template <template <class> class> class TT>
4710 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
4711 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
4713 if (!coerce_template_template_parms
4714 (parmparm, argparm, complain, in_decl, outer_args))
4720 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))
4721 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg)))
4722 /* One is a parameter pack, the other is not. */
4727 /* The tsubst call is used to handle cases such as
4729 template <int> class C {};
4730 template <class T, template <T> class TT> class D {};
4733 i.e. the parameter list of TT depends on earlier parameters. */
4734 if (!dependent_type_p (TREE_TYPE (arg))
4736 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
4740 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
4741 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg)))
4742 /* One is a parameter pack, the other is not. */
4753 /* Convert the indicated template ARG as necessary to match the
4754 indicated template PARM. Returns the converted ARG, or
4755 error_mark_node if the conversion was unsuccessful. Error and
4756 warning messages are issued under control of COMPLAIN. This
4757 conversion is for the Ith parameter in the parameter list. ARGS is
4758 the full set of template arguments deduced so far. */
4761 convert_template_argument (tree parm,
4764 tsubst_flags_t complain,
4770 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
4772 if (TREE_CODE (arg) == TREE_LIST
4773 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
4775 /* The template argument was the name of some
4776 member function. That's usually
4777 invalid, but static members are OK. In any
4778 case, grab the underlying fields/functions
4779 and issue an error later if required. */
4780 orig_arg = TREE_VALUE (arg);
4781 TREE_TYPE (arg) = unknown_type_node;
4786 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
4787 requires_type = (TREE_CODE (parm) == TYPE_DECL
4788 || requires_tmpl_type);
4790 /* When determining whether an argument pack expansion is a template,
4791 look at the pattern. */
4792 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
4793 arg = PACK_EXPANSION_PATTERN (arg);
4796 ((TREE_CODE (arg) == TEMPLATE_DECL
4797 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
4798 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
4799 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
4802 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
4803 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
4804 arg = TYPE_STUB_DECL (arg);
4806 is_type = TYPE_P (arg) || is_tmpl_type;
4808 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
4809 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
4811 pedwarn ("to refer to a type member of a template parameter, "
4812 "use %<typename %E%>", orig_arg);
4814 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
4815 TREE_OPERAND (arg, 1),
4817 complain & tf_error);
4821 if (is_type != requires_type)
4825 if (complain & tf_error)
4827 error ("type/value mismatch at argument %d in template "
4828 "parameter list for %qD",
4831 error (" expected a constant of type %qT, got %qT",
4833 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
4834 else if (requires_tmpl_type)
4835 error (" expected a class template, got %qE", orig_arg);
4837 error (" expected a type, got %qE", orig_arg);
4840 return error_mark_node;
4842 if (is_tmpl_type ^ requires_tmpl_type)
4844 if (in_decl && (complain & tf_error))
4846 error ("type/value mismatch at argument %d in template "
4847 "parameter list for %qD",
4850 error (" expected a type, got %qT", DECL_NAME (arg));
4852 error (" expected a class template, got %qT", orig_arg);
4854 return error_mark_node;
4859 if (requires_tmpl_type)
4861 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
4862 /* The number of argument required is not known yet.
4863 Just accept it for now. */
4864 val = TREE_TYPE (arg);
4867 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
4870 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
4872 if (coerce_template_template_parms (parmparm, argparm,
4878 /* TEMPLATE_TEMPLATE_PARM node is preferred over
4880 if (val != error_mark_node)
4882 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
4883 val = TREE_TYPE (val);
4884 else if (TREE_CODE (val) == TYPE_PACK_EXPANSION
4885 && DECL_TEMPLATE_TEMPLATE_PARM_P (arg))
4887 val = TREE_TYPE (arg);
4888 val = make_pack_expansion (val);
4894 if (in_decl && (complain & tf_error))
4896 error ("type/value mismatch at argument %d in "
4897 "template parameter list for %qD",
4899 error (" expected a template of type %qD, got %qD",
4903 val = error_mark_node;
4909 /* We only form one instance of each template specialization.
4910 Therefore, if we use a non-canonical variant (i.e., a
4911 typedef), any future messages referring to the type will use
4912 the typedef, which is confusing if those future uses do not
4913 themselves also use the typedef. */
4915 val = canonical_type_variant (val);
4919 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
4921 if (invalid_nontype_parm_type_p (t, complain))
4922 return error_mark_node;
4924 if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
4925 /* We used to call digest_init here. However, digest_init
4926 will report errors, which we don't want when complain
4927 is zero. More importantly, digest_init will try too
4928 hard to convert things: for example, `0' should not be
4929 converted to pointer type at this point according to
4930 the standard. Accepting this is not merely an
4931 extension, since deciding whether or not these
4932 conversions can occur is part of determining which
4933 function template to call, or whether a given explicit
4934 argument specification is valid. */
4935 val = convert_nontype_argument (t, orig_arg);
4939 if (val == NULL_TREE)
4940 val = error_mark_node;
4941 else if (val == error_mark_node && (complain & tf_error))
4942 error ("could not convert template argument %qE to %qT", orig_arg, t);
4948 /* Coerces the remaining template arguments in INNER_ARGS (from
4949 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
4950 Returns the coerced argument pack. PARM_IDX is the position of this
4951 parameter in the template parameter list. ARGS is the original
4952 template argument list. */
4954 coerce_template_parameter_pack (tree parms,
4962 tsubst_flags_t complain)
4964 tree parm = TREE_VEC_ELT (parms, parm_idx);
4965 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
4968 tree packed_types = NULL_TREE;
4970 if (arg_idx > nargs)
4973 packed_args = make_tree_vec (nargs - arg_idx);
4975 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
4976 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
4978 /* When the template parameter is a non-type template
4979 parameter pack whose type uses parameter packs, we need
4980 to look at each of the template arguments
4981 separately. Build a vector of the types for these
4982 non-type template parameters in PACKED_TYPES. */
4984 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
4985 packed_types = tsubst_pack_expansion (expansion, args,
4988 if (packed_types == error_mark_node)
4989 return error_mark_node;
4991 /* Check that we have the right number of arguments. */
4993 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
4994 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
4997 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
4998 error ("wrong number of template arguments (%d, should be %d)",
4999 nargs, needed_parms);
5000 return error_mark_node;
5003 /* If we aren't able to check the actual arguments now
5004 (because they haven't been expanded yet), we can at least
5005 verify that all of the types used for the non-type
5006 template parameter pack are, in fact, valid for non-type
5007 template parameters. */
5009 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
5011 int j, len = TREE_VEC_LENGTH (packed_types);
5012 for (j = 0; j < len; ++j)
5014 tree t = TREE_VEC_ELT (packed_types, j);
5015 if (invalid_nontype_parm_type_p (t, complain))
5016 return error_mark_node;
5021 /* Convert the remaining arguments, which will be a part of the
5022 parameter pack "parm". */
5023 for (; arg_idx < nargs; ++arg_idx)
5025 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
5026 tree actual_parm = TREE_VALUE (parm);
5028 if (packed_types && !PACK_EXPANSION_P (arg))
5030 /* When we have a vector of types (corresponding to the
5031 non-type template parameter pack that uses parameter
5032 packs in its type, as mention above), and the
5033 argument is not an expansion (which expands to a
5034 currently unknown number of arguments), clone the
5035 parm and give it the next type in PACKED_TYPES. */
5036 actual_parm = copy_node (actual_parm);
5037 TREE_TYPE (actual_parm) =
5038 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
5041 if (arg != error_mark_node)
5042 arg = convert_template_argument (actual_parm,
5043 arg, new_args, complain, parm_idx,
5045 if (arg == error_mark_node)
5047 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
5050 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
5051 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
5052 argument_pack = make_node (TYPE_ARGUMENT_PACK);
5055 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
5056 TREE_TYPE (argument_pack)
5057 = tsubst (TREE_TYPE (TREE_VALUE (parm)), args, complain, in_decl);
5058 TREE_CONSTANT (argument_pack) = 1;
5061 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
5062 return argument_pack;
5065 /* Convert all template arguments to their appropriate types, and
5066 return a vector containing the innermost resulting template
5067 arguments. If any error occurs, return error_mark_node. Error and
5068 warning messages are issued under control of COMPLAIN.
5070 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
5071 for arguments not specified in ARGS. Otherwise, if
5072 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
5073 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
5074 USE_DEFAULT_ARGS is false, then all arguments must be specified in
5078 coerce_template_parms (tree parms,
5081 tsubst_flags_t complain,
5082 bool require_all_args,
5083 bool use_default_args)
5085 int nparms, nargs, parm_idx, arg_idx, lost = 0;
5088 tree new_inner_args;
5089 bool saved_skip_evaluation;
5091 /* When used as a boolean value, indicates whether this is a
5092 variadic template parameter list. Since it's an int, we can also
5093 subtract it from nparms to get the number of non-variadic
5098 = expand_template_argument_pack (INNERMOST_TEMPLATE_ARGS (args));
5100 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5101 nparms = TREE_VEC_LENGTH (parms);
5103 /* Determine if there are any parameter packs. */
5104 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
5106 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
5107 if (template_parameter_pack_p (tparm))
5114 if ((nargs > nparms - variadic_p && !variadic_p)
5115 || (nargs < nparms - variadic_p
5117 && (!use_default_args
5118 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
5119 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
5121 if (complain & tf_error)
5123 const char *or_more = "";
5126 or_more = " or more";
5130 error ("wrong number of template arguments (%d, should be %d%s)",
5131 nargs, nparms, or_more);
5134 error ("provided for %q+D", in_decl);
5137 return error_mark_node;
5140 /* We need to evaluate the template arguments, even though this
5141 template-id may be nested within a "sizeof". */
5142 saved_skip_evaluation = skip_evaluation;
5143 skip_evaluation = false;
5144 new_inner_args = make_tree_vec (nparms);
5145 new_args = add_outermost_template_args (args, new_inner_args);
5146 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
5151 /* Get the Ith template parameter. */
5152 parm = TREE_VEC_ELT (parms, parm_idx);
5154 if (parm == error_mark_node)
5156 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
5160 /* Calculate the next argument. */
5161 if (template_parameter_pack_p (TREE_VALUE (parm)))
5163 /* All remaining arguments will be placed in the
5164 template parameter pack PARM. */
5165 arg = coerce_template_parameter_pack (parms, parm_idx, args,
5166 inner_args, arg_idx,
5170 /* Store this argument. */
5171 if (arg == error_mark_node)
5173 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
5175 /* We are done with all of the arguments. */
5180 else if (arg_idx < nargs)
5182 arg = TREE_VEC_ELT (inner_args, arg_idx);
5184 if (arg && PACK_EXPANSION_P (arg))
5186 /* If ARG is a pack expansion, but PARM is not a
5187 template parameter pack (if it were, we would have
5188 handled it above), we're trying to expand into a
5189 fixed-length argument list. */
5190 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
5191 error ("cannot expand %<%E%> into a fixed-length "
5192 "argument list", arg);
5194 error ("cannot expand %<%T%> into a fixed-length "
5195 "argument list", arg);
5196 return error_mark_node;
5199 else if (require_all_args)
5200 /* There must be a default arg in this case. */
5201 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
5206 if (arg == error_mark_node)
5208 if (complain & tf_error)
5209 error ("template argument %d is invalid", arg_idx + 1);
5212 /* This only occurs if there was an error in the template
5213 parameter list itself (which we would already have
5214 reported) that we are trying to recover from, e.g., a class
5215 template with a parameter list such as
5216 template<typename..., typename>. */
5217 return error_mark_node;
5219 arg = convert_template_argument (TREE_VALUE (parm),
5220 arg, new_args, complain,
5223 if (arg == error_mark_node)
5225 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
5227 skip_evaluation = saved_skip_evaluation;
5230 return error_mark_node;
5232 return new_inner_args;
5235 /* Returns 1 if template args OT and NT are equivalent. */
5238 template_args_equal (tree ot, tree nt)
5243 if (TREE_CODE (nt) == TREE_VEC)
5244 /* For member templates */
5245 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
5246 else if (PACK_EXPANSION_P (ot))
5247 return PACK_EXPANSION_P (nt)
5248 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
5249 PACK_EXPANSION_PATTERN (nt));
5250 else if (TYPE_P (nt))
5251 return TYPE_P (ot) && same_type_p (ot, nt);
5252 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
5255 return cp_tree_equal (ot, nt);
5258 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
5259 of template arguments. Returns 0 otherwise. */
5262 comp_template_args (tree oldargs, tree newargs)
5266 oldargs = expand_template_argument_pack (oldargs);
5267 newargs = expand_template_argument_pack (newargs);
5269 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
5272 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
5274 tree nt = TREE_VEC_ELT (newargs, i);
5275 tree ot = TREE_VEC_ELT (oldargs, i);
5277 if (! template_args_equal (ot, nt))
5284 add_pending_template (tree d)
5286 tree ti = (TYPE_P (d)
5287 ? CLASSTYPE_TEMPLATE_INFO (d)
5288 : DECL_TEMPLATE_INFO (d));
5289 struct pending_template *pt;
5292 if (TI_PENDING_TEMPLATE_FLAG (ti))
5295 /* We are called both from instantiate_decl, where we've already had a
5296 tinst_level pushed, and instantiate_template, where we haven't.
5298 level = !current_tinst_level || current_tinst_level->decl != d;
5301 push_tinst_level (d);
5303 pt = GGC_NEW (struct pending_template);
5305 pt->tinst = current_tinst_level;
5306 if (last_pending_template)
5307 last_pending_template->next = pt;
5309 pending_templates = pt;
5311 last_pending_template = pt;
5313 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
5320 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
5321 ARGLIST. Valid choices for FNS are given in the cp-tree.def
5322 documentation for TEMPLATE_ID_EXPR. */
5325 lookup_template_function (tree fns, tree arglist)
5329 if (fns == error_mark_node || arglist == error_mark_node)
5330 return error_mark_node;
5332 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
5333 gcc_assert (fns && (is_overloaded_fn (fns)
5334 || TREE_CODE (fns) == IDENTIFIER_NODE));
5336 if (BASELINK_P (fns))
5338 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
5340 BASELINK_FUNCTIONS (fns),
5345 type = TREE_TYPE (fns);
5346 if (TREE_CODE (fns) == OVERLOAD || !type)
5347 type = unknown_type_node;
5349 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
5352 /* Within the scope of a template class S<T>, the name S gets bound
5353 (in build_self_reference) to a TYPE_DECL for the class, not a
5354 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
5355 or one of its enclosing classes, and that type is a template,
5356 return the associated TEMPLATE_DECL. Otherwise, the original
5357 DECL is returned. */
5360 maybe_get_template_decl_from_type_decl (tree decl)
5362 return (decl != NULL_TREE
5363 && TREE_CODE (decl) == TYPE_DECL
5364 && DECL_ARTIFICIAL (decl)
5365 && CLASS_TYPE_P (TREE_TYPE (decl))
5366 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
5367 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
5370 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
5371 parameters, find the desired type.
5373 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
5375 IN_DECL, if non-NULL, is the template declaration we are trying to
5378 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
5379 the class we are looking up.
5381 Issue error and warning messages under control of COMPLAIN.
5383 If the template class is really a local class in a template
5384 function, then the FUNCTION_CONTEXT is the function in which it is
5387 ??? Note that this function is currently called *twice* for each
5388 template-id: the first time from the parser, while creating the
5389 incomplete type (finish_template_type), and the second type during the
5390 real instantiation (instantiate_template_class). This is surely something
5391 that we want to avoid. It also causes some problems with argument
5392 coercion (see convert_nontype_argument for more information on this). */
5395 lookup_template_class (tree d1,
5400 tsubst_flags_t complain)
5402 tree template = NULL_TREE, parmlist;
5405 timevar_push (TV_NAME_LOOKUP);
5407 if (TREE_CODE (d1) == IDENTIFIER_NODE)
5409 tree value = innermost_non_namespace_value (d1);
5410 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
5415 push_decl_namespace (context);
5416 template = lookup_name (d1);
5417 template = maybe_get_template_decl_from_type_decl (template);
5419 pop_decl_namespace ();
5422 context = DECL_CONTEXT (template);
5424 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
5426 tree type = TREE_TYPE (d1);
5428 /* If we are declaring a constructor, say A<T>::A<T>, we will get
5429 an implicit typename for the second A. Deal with it. */
5430 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
5431 type = TREE_TYPE (type);
5433 if (CLASSTYPE_TEMPLATE_INFO (type))
5435 template = CLASSTYPE_TI_TEMPLATE (type);
5436 d1 = DECL_NAME (template);
5439 else if (TREE_CODE (d1) == ENUMERAL_TYPE
5440 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
5442 template = TYPE_TI_TEMPLATE (d1);
5443 d1 = DECL_NAME (template);
5445 else if (TREE_CODE (d1) == TEMPLATE_DECL
5446 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
5449 d1 = DECL_NAME (template);
5450 context = DECL_CONTEXT (template);
5453 /* Issue an error message if we didn't find a template. */
5456 if (complain & tf_error)
5457 error ("%qT is not a template", d1);
5458 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5461 if (TREE_CODE (template) != TEMPLATE_DECL
5462 /* Make sure it's a user visible template, if it was named by
5464 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
5465 && !PRIMARY_TEMPLATE_P (template)))
5467 if (complain & tf_error)
5469 error ("non-template type %qT used as a template", d1);
5471 error ("for template declaration %q+D", in_decl);
5473 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5476 complain &= ~tf_user;
5478 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
5480 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
5481 template arguments */
5487 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
5489 /* Consider an example where a template template parameter declared as
5491 template <class T, class U = std::allocator<T> > class TT
5493 The template parameter level of T and U are one level larger than
5494 of TT. To proper process the default argument of U, say when an
5495 instantiation `TT<int>' is seen, we need to build the full
5496 arguments containing {int} as the innermost level. Outer levels,
5497 available when not appearing as default template argument, can be
5498 obtained from the arguments of the enclosing template.
5500 Suppose that TT is later substituted with std::vector. The above
5501 instantiation is `TT<int, std::allocator<T> >' with TT at
5502 level 1, and T at level 2, while the template arguments at level 1
5503 becomes {std::vector} and the inner level 2 is {int}. */
5505 outer = DECL_CONTEXT (template);
5507 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
5508 else if (current_template_parms)
5509 /* This is an argument of the current template, so we haven't set
5510 DECL_CONTEXT yet. */
5511 outer = current_template_args ();
5514 arglist = add_to_template_args (outer, arglist);
5516 arglist2 = coerce_template_parms (parmlist, arglist, template,
5518 /*require_all_args=*/true,
5519 /*use_default_args=*/true);
5520 if (arglist2 == error_mark_node
5521 || (!uses_template_parms (arglist2)
5522 && check_instantiated_args (template, arglist2, complain)))
5523 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5525 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
5526 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
5530 tree template_type = TREE_TYPE (template);
5533 tree found = NULL_TREE;
5536 int is_partial_instantiation;
5538 gen_tmpl = most_general_template (template);
5539 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
5540 parm_depth = TMPL_PARMS_DEPTH (parmlist);
5541 arg_depth = TMPL_ARGS_DEPTH (arglist);
5543 if (arg_depth == 1 && parm_depth > 1)
5545 /* We've been given an incomplete set of template arguments.
5548 template <class T> struct S1 {
5549 template <class U> struct S2 {};
5550 template <class U> struct S2<U*> {};
5553 we will be called with an ARGLIST of `U*', but the
5554 TEMPLATE will be `template <class T> template
5555 <class U> struct S1<T>::S2'. We must fill in the missing
5558 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
5560 arg_depth = TMPL_ARGS_DEPTH (arglist);
5563 /* Now we should have enough arguments. */
5564 gcc_assert (parm_depth == arg_depth);
5566 /* From here on, we're only interested in the most general
5568 template = gen_tmpl;
5570 /* Calculate the BOUND_ARGS. These will be the args that are
5571 actually tsubst'd into the definition to create the
5575 /* We have multiple levels of arguments to coerce, at once. */
5577 int saved_depth = TMPL_ARGS_DEPTH (arglist);
5579 tree bound_args = make_tree_vec (parm_depth);
5581 for (i = saved_depth,
5582 t = DECL_TEMPLATE_PARMS (template);
5583 i > 0 && t != NULL_TREE;
5584 --i, t = TREE_CHAIN (t))
5586 tree a = coerce_template_parms (TREE_VALUE (t),
5589 /*require_all_args=*/true,
5590 /*use_default_args=*/true);
5592 /* Don't process further if one of the levels fails. */
5593 if (a == error_mark_node)
5595 /* Restore the ARGLIST to its full size. */
5596 TREE_VEC_LENGTH (arglist) = saved_depth;
5597 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5600 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
5602 /* We temporarily reduce the length of the ARGLIST so
5603 that coerce_template_parms will see only the arguments
5604 corresponding to the template parameters it is
5606 TREE_VEC_LENGTH (arglist)--;
5609 /* Restore the ARGLIST to its full size. */
5610 TREE_VEC_LENGTH (arglist) = saved_depth;
5612 arglist = bound_args;
5616 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
5617 INNERMOST_TEMPLATE_ARGS (arglist),
5620 /*require_all_args=*/true,
5621 /*use_default_args=*/true);
5623 if (arglist == error_mark_node)
5624 /* We were unable to bind the arguments. */
5625 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5627 /* In the scope of a template class, explicit references to the
5628 template class refer to the type of the template, not any
5629 instantiation of it. For example, in:
5631 template <class T> class C { void f(C<T>); }
5633 the `C<T>' is just the same as `C'. Outside of the
5634 class, however, such a reference is an instantiation. */
5635 if (comp_template_args (TYPE_TI_ARGS (template_type),
5638 found = template_type;
5640 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
5644 for (ctx = current_class_type;
5645 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
5647 ? TYPE_CONTEXT (ctx)
5648 : DECL_CONTEXT (ctx)))
5649 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
5652 /* We're not in the scope of the class, so the
5653 TEMPLATE_TYPE is not the type we want after all. */
5659 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
5661 /* If we already have this specialization, return it. */
5662 found = retrieve_specialization (template, arglist,
5663 /*class_specializations_p=*/false);
5665 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
5667 /* This type is a "partial instantiation" if any of the template
5668 arguments still involve template parameters. Note that we set
5669 IS_PARTIAL_INSTANTIATION for partial specializations as
5671 is_partial_instantiation = uses_template_parms (arglist);
5673 /* If the deduced arguments are invalid, then the binding
5675 if (!is_partial_instantiation
5676 && check_instantiated_args (template,
5677 INNERMOST_TEMPLATE_ARGS (arglist),
5679 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5681 if (!is_partial_instantiation
5682 && !PRIMARY_TEMPLATE_P (template)
5683 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
5685 found = xref_tag_from_type (TREE_TYPE (template),
5686 DECL_NAME (template),
5687 /*tag_scope=*/ts_global);
5688 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
5691 context = tsubst (DECL_CONTEXT (template), arglist,
5694 context = global_namespace;
5696 /* Create the type. */
5697 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
5699 if (!is_partial_instantiation)
5701 set_current_access_from_decl (TYPE_NAME (template_type));
5702 t = start_enum (TYPE_IDENTIFIER (template_type));
5705 /* We don't want to call start_enum for this type, since
5706 the values for the enumeration constants may involve
5707 template parameters. And, no one should be interested
5708 in the enumeration constants for such a type. */
5709 t = make_node (ENUMERAL_TYPE);
5713 t = make_aggr_type (TREE_CODE (template_type));
5714 CLASSTYPE_DECLARED_CLASS (t)
5715 = CLASSTYPE_DECLARED_CLASS (template_type);
5716 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
5717 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
5719 /* A local class. Make sure the decl gets registered properly. */
5720 if (context == current_function_decl)
5721 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
5723 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
5724 /* This instantiation is another name for the primary
5725 template type. Set the TYPE_CANONICAL field
5727 TYPE_CANONICAL (t) = template_type;
5728 else if (any_template_arguments_need_structural_equality_p (arglist))
5729 /* Some of the template arguments require structural
5730 equality testing, so this template class requires
5731 structural equality testing. */
5732 SET_TYPE_STRUCTURAL_EQUALITY (t);
5735 /* If we called start_enum or pushtag above, this information
5736 will already be set up. */
5739 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
5741 type_decl = create_implicit_typedef (DECL_NAME (template), t);
5742 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
5743 TYPE_STUB_DECL (t) = type_decl;
5744 DECL_SOURCE_LOCATION (type_decl)
5745 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
5748 type_decl = TYPE_NAME (t);
5750 TREE_PRIVATE (type_decl)
5751 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
5752 TREE_PROTECTED (type_decl)
5753 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
5754 DECL_IN_SYSTEM_HEADER (type_decl)
5755 = DECL_IN_SYSTEM_HEADER (template);
5756 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
5758 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
5759 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
5762 /* Set up the template information. We have to figure out which
5763 template is the immediate parent if this is a full
5765 if (parm_depth == 1 || is_partial_instantiation
5766 || !PRIMARY_TEMPLATE_P (template))
5767 /* This case is easy; there are no member templates involved. */
5771 /* This is a full instantiation of a member template. Look
5772 for a partial instantiation of which this is an instance. */
5774 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
5775 found; found = TREE_CHAIN (found))
5778 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
5780 /* We only want partial instantiations, here, not
5781 specializations or full instantiations. */
5782 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
5783 || !uses_template_parms (TREE_VALUE (found)))
5786 /* Temporarily reduce by one the number of levels in the
5787 ARGLIST and in FOUND so as to avoid comparing the
5788 last set of arguments. */
5789 TREE_VEC_LENGTH (arglist)--;
5790 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
5792 /* See if the arguments match. If they do, then TMPL is
5793 the partial instantiation we want. */
5794 success = comp_template_args (TREE_PURPOSE (found), arglist);
5796 /* Restore the argument vectors to their full size. */
5797 TREE_VEC_LENGTH (arglist)++;
5798 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
5809 /* There was no partial instantiation. This happens
5810 where C<T> is a member template of A<T> and it's used
5813 template <typename T> struct B { A<T>::C<int> m; };
5816 Create the partial instantiation.
5818 TREE_VEC_LENGTH (arglist)--;
5819 found = tsubst (template, arglist, complain, NULL_TREE);
5820 TREE_VEC_LENGTH (arglist)++;
5824 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
5825 DECL_TEMPLATE_INSTANTIATIONS (template)
5826 = tree_cons (arglist, t,
5827 DECL_TEMPLATE_INSTANTIATIONS (template));
5829 if (TREE_CODE (t) == ENUMERAL_TYPE
5830 && !is_partial_instantiation)
5831 /* Now that the type has been registered on the instantiations
5832 list, we set up the enumerators. Because the enumeration
5833 constants may involve the enumeration type itself, we make
5834 sure to register the type first, and then create the
5835 constants. That way, doing tsubst_expr for the enumeration
5836 constants won't result in recursive calls here; we'll find
5837 the instantiation and exit above. */
5838 tsubst_enum (template_type, t, arglist);
5840 if (is_partial_instantiation)
5841 /* If the type makes use of template parameters, the
5842 code that generates debugging information will crash. */
5843 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
5845 /* Possibly limit visibility based on template args. */
5846 TREE_PUBLIC (type_decl) = 1;
5847 determine_visibility (type_decl);
5849 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
5851 timevar_pop (TV_NAME_LOOKUP);
5858 struct pointer_set_t *visited;
5861 /* Called from for_each_template_parm via walk_tree. */
5864 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
5867 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
5868 tree_fn_t fn = pfd->fn;
5869 void *data = pfd->data;
5872 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
5873 return error_mark_node;
5875 switch (TREE_CODE (t))
5878 if (TYPE_PTRMEMFUNC_P (t))
5884 if (!TYPE_TEMPLATE_INFO (t))
5886 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
5887 fn, data, pfd->visited))
5888 return error_mark_node;
5892 if (for_each_template_parm (TYPE_MIN_VALUE (t),
5893 fn, data, pfd->visited)
5894 || for_each_template_parm (TYPE_MAX_VALUE (t),
5895 fn, data, pfd->visited))
5896 return error_mark_node;
5900 /* Since we're not going to walk subtrees, we have to do this
5902 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
5904 return error_mark_node;
5908 /* Check the return type. */
5909 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
5910 return error_mark_node;
5912 /* Check the parameter types. Since default arguments are not
5913 instantiated until they are needed, the TYPE_ARG_TYPES may
5914 contain expressions that involve template parameters. But,
5915 no-one should be looking at them yet. And, once they're
5916 instantiated, they don't contain template parameters, so
5917 there's no point in looking at them then, either. */
5921 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
5922 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
5924 return error_mark_node;
5926 /* Since we've already handled the TYPE_ARG_TYPES, we don't
5927 want walk_tree walking into them itself. */
5933 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
5935 return error_mark_node;
5940 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
5941 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
5943 return error_mark_node;
5948 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
5949 && for_each_template_parm (DECL_INITIAL (t), fn, data,
5951 return error_mark_node;
5952 if (DECL_CONTEXT (t)
5953 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
5955 return error_mark_node;
5958 case BOUND_TEMPLATE_TEMPLATE_PARM:
5959 /* Record template parameters such as `T' inside `TT<T>'. */
5960 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
5961 return error_mark_node;
5964 case TEMPLATE_TEMPLATE_PARM:
5965 case TEMPLATE_TYPE_PARM:
5966 case TEMPLATE_PARM_INDEX:
5967 if (fn && (*fn)(t, data))
5968 return error_mark_node;
5970 return error_mark_node;
5974 /* A template template parameter is encountered. */
5975 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
5976 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
5977 return error_mark_node;
5979 /* Already substituted template template parameter */
5985 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
5986 data, pfd->visited))
5987 return error_mark_node;
5991 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
5992 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
5993 (TREE_TYPE (t)), fn, data,
5995 return error_mark_node;
6000 /* If there's no type, then this thing must be some expression
6001 involving template parameters. */
6002 if (!fn && !TREE_TYPE (t))
6003 return error_mark_node;
6008 case REINTERPRET_CAST_EXPR:
6009 case CONST_CAST_EXPR:
6010 case STATIC_CAST_EXPR:
6011 case DYNAMIC_CAST_EXPR:
6015 case PSEUDO_DTOR_EXPR:
6017 return error_mark_node;
6024 /* We didn't find any template parameters we liked. */
6028 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
6029 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
6030 call FN with the parameter and the DATA.
6031 If FN returns nonzero, the iteration is terminated, and
6032 for_each_template_parm returns 1. Otherwise, the iteration
6033 continues. If FN never returns a nonzero value, the value
6034 returned by for_each_template_parm is 0. If FN is NULL, it is
6035 considered to be the function which always returns 1. */
6038 for_each_template_parm (tree t, tree_fn_t fn, void* data,
6039 struct pointer_set_t *visited)
6041 struct pair_fn_data pfd;
6048 /* Walk the tree. (Conceptually, we would like to walk without
6049 duplicates, but for_each_template_parm_r recursively calls
6050 for_each_template_parm, so we would need to reorganize a fair
6051 bit to use walk_tree_without_duplicates, so we keep our own
6054 pfd.visited = visited;
6056 pfd.visited = pointer_set_create ();
6057 result = cp_walk_tree (&t,
6058 for_each_template_parm_r,
6060 pfd.visited) != NULL_TREE;
6065 pointer_set_destroy (pfd.visited);
6072 /* Returns true if T depends on any template parameter. */
6075 uses_template_parms (tree t)
6078 int saved_processing_template_decl;
6080 saved_processing_template_decl = processing_template_decl;
6081 if (!saved_processing_template_decl)
6082 processing_template_decl = 1;
6084 dependent_p = dependent_type_p (t);
6085 else if (TREE_CODE (t) == TREE_VEC)
6086 dependent_p = any_dependent_template_arguments_p (t);
6087 else if (TREE_CODE (t) == TREE_LIST)
6088 dependent_p = (uses_template_parms (TREE_VALUE (t))
6089 || uses_template_parms (TREE_CHAIN (t)));
6090 else if (TREE_CODE (t) == TYPE_DECL)
6091 dependent_p = dependent_type_p (TREE_TYPE (t));
6094 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
6095 || TREE_CODE (t) == OVERLOAD
6096 || TREE_CODE (t) == BASELINK
6097 || TREE_CODE (t) == IDENTIFIER_NODE
6098 || TREE_CODE (t) == TRAIT_EXPR
6099 || CONSTANT_CLASS_P (t))
6100 dependent_p = (type_dependent_expression_p (t)
6101 || value_dependent_expression_p (t));
6104 gcc_assert (t == error_mark_node);
6105 dependent_p = false;
6108 processing_template_decl = saved_processing_template_decl;
6113 /* Returns true if T depends on any template parameter with level LEVEL. */
6116 uses_template_parms_level (tree t, int level)
6118 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
6121 static int tinst_depth;
6122 extern int max_tinst_depth;
6123 #ifdef GATHER_STATISTICS
6126 static int tinst_level_tick;
6127 static int last_template_error_tick;
6129 /* We're starting to instantiate D; record the template instantiation context
6130 for diagnostics and to restore it later. */
6133 push_tinst_level (tree d)
6135 struct tinst_level *new;
6137 if (tinst_depth >= max_tinst_depth)
6139 /* If the instantiation in question still has unbound template parms,
6140 we don't really care if we can't instantiate it, so just return.
6141 This happens with base instantiation for implicit `typename'. */
6142 if (uses_template_parms (d))
6145 last_template_error_tick = tinst_level_tick;
6146 error ("template instantiation depth exceeds maximum of %d (use "
6147 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
6148 max_tinst_depth, d);
6150 print_instantiation_context ();
6155 new = GGC_NEW (struct tinst_level);
6157 new->locus = input_location;
6158 new->in_system_header_p = in_system_header;
6159 new->next = current_tinst_level;
6160 current_tinst_level = new;
6163 #ifdef GATHER_STATISTICS
6164 if (tinst_depth > depth_reached)
6165 depth_reached = tinst_depth;
6172 /* We're done instantiating this template; return to the instantiation
6176 pop_tinst_level (void)
6178 /* Restore the filename and line number stashed away when we started
6179 this instantiation. */
6180 input_location = current_tinst_level->locus;
6181 in_system_header = current_tinst_level->in_system_header_p;
6182 current_tinst_level = current_tinst_level->next;
6187 /* We're instantiating a deferred template; restore the template
6188 instantiation context in which the instantiation was requested, which
6189 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
6192 reopen_tinst_level (struct tinst_level *level)
6194 struct tinst_level *t;
6197 for (t = level; t; t = t->next)
6200 current_tinst_level = level;
6205 /* Returns the TINST_LEVEL which gives the original instantiation
6208 struct tinst_level *
6209 outermost_tinst_level (void)
6211 struct tinst_level *level = current_tinst_level;
6214 level = level->next;
6218 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
6219 vector of template arguments, as for tsubst.
6221 Returns an appropriate tsubst'd friend declaration. */
6224 tsubst_friend_function (tree decl, tree args)
6228 if (TREE_CODE (decl) == FUNCTION_DECL
6229 && DECL_TEMPLATE_INSTANTIATION (decl)
6230 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
6231 /* This was a friend declared with an explicit template
6232 argument list, e.g.:
6236 to indicate that f was a template instantiation, not a new
6237 function declaration. Now, we have to figure out what
6238 instantiation of what template. */
6240 tree template_id, arglist, fns;
6243 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
6245 /* Friend functions are looked up in the containing namespace scope.
6246 We must enter that scope, to avoid finding member functions of the
6247 current cless with same name. */
6248 push_nested_namespace (ns);
6249 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
6250 tf_warning_or_error, NULL_TREE,
6251 /*integral_constant_expression_p=*/false);
6252 pop_nested_namespace (ns);
6253 arglist = tsubst (DECL_TI_ARGS (decl), args,
6254 tf_warning_or_error, NULL_TREE);
6255 template_id = lookup_template_function (fns, arglist);
6257 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6258 tmpl = determine_specialization (template_id, new_friend,
6260 /*need_member_template=*/0,
6261 TREE_VEC_LENGTH (args),
6263 return instantiate_template (tmpl, new_args, tf_error);
6266 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6268 /* The NEW_FRIEND will look like an instantiation, to the
6269 compiler, but is not an instantiation from the point of view of
6270 the language. For example, we might have had:
6272 template <class T> struct S {
6273 template <class U> friend void f(T, U);
6276 Then, in S<int>, template <class U> void f(int, U) is not an
6277 instantiation of anything. */
6278 if (new_friend == error_mark_node)
6279 return error_mark_node;
6281 DECL_USE_TEMPLATE (new_friend) = 0;
6282 if (TREE_CODE (decl) == TEMPLATE_DECL)
6284 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
6285 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
6286 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
6289 /* The mangled name for the NEW_FRIEND is incorrect. The function
6290 is not a template instantiation and should not be mangled like
6291 one. Therefore, we forget the mangling here; we'll recompute it
6292 later if we need it. */
6293 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
6295 SET_DECL_RTL (new_friend, NULL_RTX);
6296 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
6299 if (DECL_NAMESPACE_SCOPE_P (new_friend))
6302 tree new_friend_template_info;
6303 tree new_friend_result_template_info;
6305 int new_friend_is_defn;
6307 /* We must save some information from NEW_FRIEND before calling
6308 duplicate decls since that function will free NEW_FRIEND if
6310 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
6311 new_friend_is_defn =
6312 (DECL_INITIAL (DECL_TEMPLATE_RESULT
6313 (template_for_substitution (new_friend)))
6315 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
6317 /* This declaration is a `primary' template. */
6318 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
6320 new_friend_result_template_info
6321 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
6324 new_friend_result_template_info = NULL_TREE;
6326 /* Make the init_value nonzero so pushdecl knows this is a defn. */
6327 if (new_friend_is_defn)
6328 DECL_INITIAL (new_friend) = error_mark_node;
6330 /* Inside pushdecl_namespace_level, we will push into the
6331 current namespace. However, the friend function should go
6332 into the namespace of the template. */
6333 ns = decl_namespace_context (new_friend);
6334 push_nested_namespace (ns);
6335 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
6336 pop_nested_namespace (ns);
6338 if (old_decl == error_mark_node)
6339 return error_mark_node;
6341 if (old_decl != new_friend)
6343 /* This new friend declaration matched an existing
6344 declaration. For example, given:
6346 template <class T> void f(T);
6347 template <class U> class C {
6348 template <class T> friend void f(T) {}
6351 the friend declaration actually provides the definition
6352 of `f', once C has been instantiated for some type. So,
6353 old_decl will be the out-of-class template declaration,
6354 while new_friend is the in-class definition.
6356 But, if `f' was called before this point, the
6357 instantiation of `f' will have DECL_TI_ARGS corresponding
6358 to `T' but not to `U', references to which might appear
6359 in the definition of `f'. Previously, the most general
6360 template for an instantiation of `f' was the out-of-class
6361 version; now it is the in-class version. Therefore, we
6362 run through all specialization of `f', adding to their
6363 DECL_TI_ARGS appropriately. In particular, they need a
6364 new set of outer arguments, corresponding to the
6365 arguments for this class instantiation.
6367 The same situation can arise with something like this:
6370 template <class T> class C {
6374 when `C<int>' is instantiated. Now, `f(int)' is defined
6377 if (!new_friend_is_defn)
6378 /* On the other hand, if the in-class declaration does
6379 *not* provide a definition, then we don't want to alter
6380 existing definitions. We can just leave everything
6385 /* Overwrite whatever template info was there before, if
6386 any, with the new template information pertaining to
6388 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
6390 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
6391 reregister_specialization (new_friend,
6392 most_general_template (old_decl),
6397 tree new_friend_args;
6399 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
6400 = new_friend_result_template_info;
6402 new_friend_args = TI_ARGS (new_friend_template_info);
6403 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
6407 tree spec = TREE_VALUE (t);
6410 = add_outermost_template_args (new_friend_args,
6411 DECL_TI_ARGS (spec));
6414 /* Now, since specializations are always supposed to
6415 hang off of the most general template, we must move
6417 t = most_general_template (old_decl);
6420 DECL_TEMPLATE_SPECIALIZATIONS (t)
6421 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
6422 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
6423 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
6428 /* The information from NEW_FRIEND has been merged into OLD_DECL
6429 by duplicate_decls. */
6430 new_friend = old_decl;
6435 tree context = DECL_CONTEXT (new_friend);
6439 template <class T> class C {
6440 template <class U> friend void C1<U>::f (); // case 1
6441 friend void C2<T>::f (); // case 2
6443 we only need to make sure CONTEXT is a complete type for
6444 case 2. To distinguish between the two cases, we note that
6445 CONTEXT of case 1 remains dependent type after tsubst while
6446 this isn't true for case 2. */
6447 ++processing_template_decl;
6448 dependent_p = dependent_type_p (context);
6449 --processing_template_decl;
6452 && !complete_type_or_else (context, NULL_TREE))
6453 return error_mark_node;
6455 if (COMPLETE_TYPE_P (context))
6457 /* Check to see that the declaration is really present, and,
6458 possibly obtain an improved declaration. */
6459 tree fn = check_classfn (context,
6460 new_friend, NULL_TREE);
6470 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
6471 template arguments, as for tsubst.
6473 Returns an appropriate tsubst'd friend type or error_mark_node on
6477 tsubst_friend_class (tree friend_tmpl, tree args)
6483 context = DECL_CONTEXT (friend_tmpl);
6487 if (TREE_CODE (context) == NAMESPACE_DECL)
6488 push_nested_namespace (context);
6490 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
6493 /* Look for a class template declaration. We look for hidden names
6494 because two friend declarations of the same template are the
6495 same. For example, in:
6498 template <typename> friend class F;
6500 template <typename> struct B {
6501 template <typename> friend class F;
6504 both F templates are the same. */
6505 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
6506 /*block_p=*/true, 0,
6507 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
6509 /* But, if we don't find one, it might be because we're in a
6510 situation like this:
6518 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
6519 for `S<int>', not the TEMPLATE_DECL. */
6520 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
6522 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
6523 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
6526 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
6528 /* The friend template has already been declared. Just
6529 check to see that the declarations match, and install any new
6530 default parameters. We must tsubst the default parameters,
6531 of course. We only need the innermost template parameters
6532 because that is all that redeclare_class_template will look
6534 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
6535 > TMPL_ARGS_DEPTH (args))
6538 location_t saved_input_location;
6539 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
6540 args, tf_warning_or_error);
6542 saved_input_location = input_location;
6543 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
6544 redeclare_class_template (TREE_TYPE (tmpl), parms);
6545 input_location = saved_input_location;
6549 friend_type = TREE_TYPE (tmpl);
6553 /* The friend template has not already been declared. In this
6554 case, the instantiation of the template class will cause the
6555 injection of this template into the global scope. */
6556 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
6557 if (tmpl == error_mark_node)
6558 return error_mark_node;
6560 /* The new TMPL is not an instantiation of anything, so we
6561 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
6562 the new type because that is supposed to be the corresponding
6563 template decl, i.e., TMPL. */
6564 DECL_USE_TEMPLATE (tmpl) = 0;
6565 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
6566 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
6567 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
6568 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
6570 /* Inject this template into the global scope. */
6571 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
6576 if (TREE_CODE (context) == NAMESPACE_DECL)
6577 pop_nested_namespace (context);
6579 pop_nested_class ();
6585 /* Returns zero if TYPE cannot be completed later due to circularity.
6586 Otherwise returns one. */
6589 can_complete_type_without_circularity (tree type)
6591 if (type == NULL_TREE || type == error_mark_node)
6593 else if (COMPLETE_TYPE_P (type))
6595 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
6596 return can_complete_type_without_circularity (TREE_TYPE (type));
6597 else if (CLASS_TYPE_P (type)
6598 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
6604 /* Apply any attributes which had to be deferred until instantiation
6605 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
6606 ARGS, COMPLAIN, IN_DECL are as tsubst. */
6609 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
6610 tree args, tsubst_flags_t complain, tree in_decl)
6612 tree last_dep = NULL_TREE;
6616 for (t = attributes; t; t = TREE_CHAIN (t))
6617 if (ATTR_IS_DEPENDENT (t))
6620 attributes = copy_list (attributes);
6624 if (DECL_P (*decl_p))
6625 p = &DECL_ATTRIBUTES (*decl_p);
6627 p = &TYPE_ATTRIBUTES (*decl_p);
6631 tree late_attrs = NULL_TREE;
6632 tree *q = &late_attrs;
6634 for (*p = attributes; *p; )
6637 if (ATTR_IS_DEPENDENT (t))
6639 *p = TREE_CHAIN (t);
6640 TREE_CHAIN (t) = NULL_TREE;
6642 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
6643 /*integral_constant_expression_p=*/false);
6645 q = &TREE_CHAIN (t);
6648 p = &TREE_CHAIN (t);
6651 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
6656 instantiate_class_template (tree type)
6658 tree template, args, pattern, t, member;
6663 if (type == error_mark_node)
6664 return error_mark_node;
6666 if (TYPE_BEING_DEFINED (type)
6667 || COMPLETE_TYPE_P (type)
6668 || dependent_type_p (type))
6671 /* Figure out which template is being instantiated. */
6672 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
6673 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
6675 /* Determine what specialization of the original template to
6677 t = most_specialized_class (type, template);
6678 if (t == error_mark_node)
6680 TYPE_BEING_DEFINED (type) = 1;
6681 return error_mark_node;
6685 /* This TYPE is actually an instantiation of a partial
6686 specialization. We replace the innermost set of ARGS with
6687 the arguments appropriate for substitution. For example,
6690 template <class T> struct S {};
6691 template <class T> struct S<T*> {};
6693 and supposing that we are instantiating S<int*>, ARGS will
6694 presently be {int*} -- but we need {int}. */
6695 pattern = TREE_TYPE (t);
6696 args = TREE_PURPOSE (t);
6700 pattern = TREE_TYPE (template);
6701 args = CLASSTYPE_TI_ARGS (type);
6704 /* If the template we're instantiating is incomplete, then clearly
6705 there's nothing we can do. */
6706 if (!COMPLETE_TYPE_P (pattern))
6709 /* If we've recursively instantiated too many templates, stop. */
6710 if (! push_tinst_level (type))
6713 /* Now we're really doing the instantiation. Mark the type as in
6714 the process of being defined. */
6715 TYPE_BEING_DEFINED (type) = 1;
6717 /* We may be in the middle of deferred access check. Disable
6719 push_deferring_access_checks (dk_no_deferred);
6721 push_to_top_level ();
6723 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
6725 /* Set the input location to the template definition. This is needed
6726 if tsubsting causes an error. */
6727 typedecl = TYPE_MAIN_DECL (type);
6728 input_location = DECL_SOURCE_LOCATION (typedecl);
6729 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
6731 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
6732 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
6733 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
6734 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
6735 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
6736 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
6737 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
6738 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
6739 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
6740 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
6741 TYPE_PACKED (type) = TYPE_PACKED (pattern);
6742 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
6743 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
6744 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
6745 if (ANON_AGGR_TYPE_P (pattern))
6746 SET_ANON_AGGR_TYPE_P (type);
6747 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
6749 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
6750 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
6753 pbinfo = TYPE_BINFO (pattern);
6755 /* We should never instantiate a nested class before its enclosing
6756 class; we need to look up the nested class by name before we can
6757 instantiate it, and that lookup should instantiate the enclosing
6759 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
6760 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
6761 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
6763 base_list = NULL_TREE;
6764 if (BINFO_N_BASE_BINFOS (pbinfo))
6767 tree context = TYPE_CONTEXT (type);
6771 /* We must enter the scope containing the type, as that is where
6772 the accessibility of types named in dependent bases are
6774 pushed_scope = push_scope (context ? context : global_namespace);
6776 /* Substitute into each of the bases to determine the actual
6778 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
6781 tree access = BINFO_BASE_ACCESS (pbinfo, i);
6782 tree expanded_bases = NULL_TREE;
6785 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
6788 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
6789 args, tf_error, NULL_TREE);
6790 if (expanded_bases == error_mark_node)
6793 len = TREE_VEC_LENGTH (expanded_bases);
6796 for (idx = 0; idx < len; idx++)
6799 /* Extract the already-expanded base class. */
6800 base = TREE_VEC_ELT (expanded_bases, idx);
6802 /* Substitute to figure out the base class. */
6803 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
6806 if (base == error_mark_node)
6809 base_list = tree_cons (access, base, base_list);
6810 if (BINFO_VIRTUAL_P (pbase_binfo))
6811 TREE_TYPE (base_list) = integer_type_node;
6815 /* The list is now in reverse order; correct that. */
6816 base_list = nreverse (base_list);
6819 pop_scope (pushed_scope);
6821 /* Now call xref_basetypes to set up all the base-class
6823 xref_basetypes (type, base_list);
6825 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
6826 (int) ATTR_FLAG_TYPE_IN_PLACE,
6827 args, tf_error, NULL_TREE);
6829 /* Now that our base classes are set up, enter the scope of the
6830 class, so that name lookups into base classes, etc. will work
6831 correctly. This is precisely analogous to what we do in
6832 begin_class_definition when defining an ordinary non-template
6833 class, except we also need to push the enclosing classes. */
6834 push_nested_class (type);
6836 /* Now members are processed in the order of declaration. */
6837 for (member = CLASSTYPE_DECL_LIST (pattern);
6838 member; member = TREE_CHAIN (member))
6840 tree t = TREE_VALUE (member);
6842 if (TREE_PURPOSE (member))
6846 /* Build new CLASSTYPE_NESTED_UTDS. */
6849 bool class_template_p;
6851 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
6852 && TYPE_LANG_SPECIFIC (t)
6853 && CLASSTYPE_IS_TEMPLATE (t));
6854 /* If the member is a class template, then -- even after
6855 substitution -- there may be dependent types in the
6856 template argument list for the class. We increment
6857 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
6858 that function will assume that no types are dependent
6859 when outside of a template. */
6860 if (class_template_p)
6861 ++processing_template_decl;
6862 newtag = tsubst (t, args, tf_error, NULL_TREE);
6863 if (class_template_p)
6864 --processing_template_decl;
6865 if (newtag == error_mark_node)
6868 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
6870 tree name = TYPE_IDENTIFIER (t);
6872 if (class_template_p)
6873 /* Unfortunately, lookup_template_class sets
6874 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
6875 instantiation (i.e., for the type of a member
6876 template class nested within a template class.)
6877 This behavior is required for
6878 maybe_process_partial_specialization to work
6879 correctly, but is not accurate in this case;
6880 the TAG is not an instantiation of anything.
6881 (The corresponding TEMPLATE_DECL is an
6882 instantiation, but the TYPE is not.) */
6883 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
6885 /* Now, we call pushtag to put this NEWTAG into the scope of
6886 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
6887 pushtag calling push_template_decl. We don't have to do
6888 this for enums because it will already have been done in
6891 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
6892 pushtag (name, newtag, /*tag_scope=*/ts_current);
6895 else if (TREE_CODE (t) == FUNCTION_DECL
6896 || DECL_FUNCTION_TEMPLATE_P (t))
6898 /* Build new TYPE_METHODS. */
6901 if (TREE_CODE (t) == TEMPLATE_DECL)
6902 ++processing_template_decl;
6903 r = tsubst (t, args, tf_error, NULL_TREE);
6904 if (TREE_CODE (t) == TEMPLATE_DECL)
6905 --processing_template_decl;
6906 set_current_access_from_decl (r);
6907 finish_member_declaration (r);
6911 /* Build new TYPE_FIELDS. */
6912 if (TREE_CODE (t) == STATIC_ASSERT)
6915 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
6916 tf_warning_or_error, NULL_TREE,
6917 /*integral_constant_expression_p=*/true);
6918 finish_static_assert (condition,
6919 STATIC_ASSERT_MESSAGE (t),
6920 STATIC_ASSERT_SOURCE_LOCATION (t),
6923 else if (TREE_CODE (t) != CONST_DECL)
6927 /* The the file and line for this declaration, to
6928 assist in error message reporting. Since we
6929 called push_tinst_level above, we don't need to
6931 input_location = DECL_SOURCE_LOCATION (t);
6933 if (TREE_CODE (t) == TEMPLATE_DECL)
6934 ++processing_template_decl;
6935 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
6936 if (TREE_CODE (t) == TEMPLATE_DECL)
6937 --processing_template_decl;
6938 if (TREE_CODE (r) == VAR_DECL)
6942 [t]he initialization (and any associated
6943 side-effects) of a static data member does
6944 not occur unless the static data member is
6945 itself used in a way that requires the
6946 definition of the static data member to
6949 Therefore, we do not substitute into the
6950 initialized for the static data member here. */
6951 finish_static_data_member_decl
6954 /*init_const_expr_p=*/false,
6955 /*asmspec_tree=*/NULL_TREE,
6957 if (DECL_INITIALIZED_IN_CLASS_P (r))
6958 check_static_variable_definition (r, TREE_TYPE (r));
6960 else if (TREE_CODE (r) == FIELD_DECL)
6962 /* Determine whether R has a valid type and can be
6963 completed later. If R is invalid, then it is
6964 replaced by error_mark_node so that it will not be
6965 added to TYPE_FIELDS. */
6966 tree rtype = TREE_TYPE (r);
6967 if (can_complete_type_without_circularity (rtype))
6968 complete_type (rtype);
6970 if (!COMPLETE_TYPE_P (rtype))
6972 cxx_incomplete_type_error (r, rtype);
6973 r = error_mark_node;
6977 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
6978 such a thing will already have been added to the field
6979 list by tsubst_enum in finish_member_declaration in the
6980 CLASSTYPE_NESTED_UTDS case above. */
6981 if (!(TREE_CODE (r) == TYPE_DECL
6982 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
6983 && DECL_ARTIFICIAL (r)))
6985 set_current_access_from_decl (r);
6986 finish_member_declaration (r);
6993 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
6995 /* Build new CLASSTYPE_FRIEND_CLASSES. */
6997 tree friend_type = t;
6998 bool adjust_processing_template_decl = false;
7000 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7002 /* template <class T> friend class C; */
7003 friend_type = tsubst_friend_class (friend_type, args);
7004 adjust_processing_template_decl = true;
7006 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
7008 /* template <class T> friend class C::D; */
7009 friend_type = tsubst (friend_type, args,
7010 tf_warning_or_error, NULL_TREE);
7011 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7012 friend_type = TREE_TYPE (friend_type);
7013 adjust_processing_template_decl = true;
7015 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
7017 /* This could be either
7021 when dependent_type_p is false or
7023 template <class U> friend class T::C;
7026 friend_type = tsubst (friend_type, args,
7027 tf_warning_or_error, NULL_TREE);
7028 /* Bump processing_template_decl for correct
7029 dependent_type_p calculation. */
7030 ++processing_template_decl;
7031 if (dependent_type_p (friend_type))
7032 adjust_processing_template_decl = true;
7033 --processing_template_decl;
7035 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
7036 && hidden_name_p (TYPE_NAME (friend_type)))
7040 where C hasn't been declared yet. Let's lookup name
7041 from namespace scope directly, bypassing any name that
7042 come from dependent base class. */
7043 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
7045 /* The call to xref_tag_from_type does injection for friend
7047 push_nested_namespace (ns);
7049 xref_tag_from_type (friend_type, NULL_TREE,
7050 /*tag_scope=*/ts_current);
7051 pop_nested_namespace (ns);
7053 else if (uses_template_parms (friend_type))
7054 /* friend class C<T>; */
7055 friend_type = tsubst (friend_type, args,
7056 tf_warning_or_error, NULL_TREE);
7061 where C is already declared or
7063 friend class C<int>;
7065 We don't have to do anything in these cases. */
7067 if (adjust_processing_template_decl)
7068 /* Trick make_friend_class into realizing that the friend
7069 we're adding is a template, not an ordinary class. It's
7070 important that we use make_friend_class since it will
7071 perform some error-checking and output cross-reference
7073 ++processing_template_decl;
7075 if (friend_type != error_mark_node)
7076 make_friend_class (type, friend_type, /*complain=*/false);
7078 if (adjust_processing_template_decl)
7079 --processing_template_decl;
7083 /* Build new DECL_FRIENDLIST. */
7086 /* The the file and line for this declaration, to
7087 assist in error message reporting. Since we
7088 called push_tinst_level above, we don't need to
7090 input_location = DECL_SOURCE_LOCATION (t);
7092 if (TREE_CODE (t) == TEMPLATE_DECL)
7094 ++processing_template_decl;
7095 push_deferring_access_checks (dk_no_check);
7098 r = tsubst_friend_function (t, args);
7099 add_friend (type, r, /*complain=*/false);
7100 if (TREE_CODE (t) == TEMPLATE_DECL)
7102 pop_deferring_access_checks ();
7103 --processing_template_decl;
7109 /* Set the file and line number information to whatever is given for
7110 the class itself. This puts error messages involving generated
7111 implicit functions at a predictable point, and the same point
7112 that would be used for non-template classes. */
7113 input_location = DECL_SOURCE_LOCATION (typedecl);
7115 unreverse_member_declarations (type);
7116 finish_struct_1 (type);
7117 TYPE_BEING_DEFINED (type) = 0;
7119 /* Now that the class is complete, instantiate default arguments for
7120 any member functions. We don't do this earlier because the
7121 default arguments may reference members of the class. */
7122 if (!PRIMARY_TEMPLATE_P (template))
7123 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
7124 if (TREE_CODE (t) == FUNCTION_DECL
7125 /* Implicitly generated member functions will not have template
7126 information; they are not instantiations, but instead are
7127 created "fresh" for each instantiation. */
7128 && DECL_TEMPLATE_INFO (t))
7129 tsubst_default_arguments (t);
7131 pop_nested_class ();
7132 pop_from_top_level ();
7133 pop_deferring_access_checks ();
7136 /* The vtable for a template class can be emitted in any translation
7137 unit in which the class is instantiated. When there is no key
7138 method, however, finish_struct_1 will already have added TYPE to
7139 the keyed_classes list. */
7140 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
7141 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
7147 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7153 else if (TYPE_P (t))
7154 r = tsubst (t, args, complain, in_decl);
7157 r = tsubst_expr (t, args, complain, in_decl,
7158 /*integral_constant_expression_p=*/true);
7159 r = fold_non_dependent_expr (r);
7164 /* Substitute ARGS into T, which is an pack expansion
7165 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
7166 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
7167 (if only a partial substitution could be performed) or
7168 ERROR_MARK_NODE if there was an error. */
7170 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
7174 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
7175 tree first_arg_pack; int i, len = -1;
7179 gcc_assert (PACK_EXPANSION_P (t));
7180 pattern = PACK_EXPANSION_PATTERN (t);
7182 /* Determine the argument packs that will instantiate the parameter
7183 packs used in the expansion expression. While we're at it,
7184 compute the number of arguments to be expanded and make sure it
7186 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
7187 pack = TREE_CHAIN (pack))
7189 tree parm_pack = TREE_VALUE (pack);
7190 tree arg_pack = NULL_TREE;
7191 tree orig_arg = NULL_TREE;
7193 if (TREE_CODE (parm_pack) == PARM_DECL)
7195 if (local_specializations)
7196 arg_pack = retrieve_local_specialization (parm_pack);
7200 int level, idx, levels;
7201 template_parm_level_and_index (parm_pack, &level, &idx);
7203 levels = TMPL_ARGS_DEPTH (args);
7204 if (level <= levels)
7205 arg_pack = TMPL_ARG (args, level, idx);
7208 orig_arg = arg_pack;
7209 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
7210 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
7212 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
7213 /* This can only happen if we forget to expand an argument
7214 pack somewhere else. Just return an error, silently. */
7216 result = make_tree_vec (1);
7217 TREE_VEC_ELT (result, 0) = error_mark_node;
7222 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
7223 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
7225 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
7226 tree pattern = PACK_EXPANSION_PATTERN (expansion);
7227 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
7228 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
7229 /* The argument pack that the parameter maps to is just an
7230 expansion of the parameter itself, such as one would
7231 find in the implicit typedef of a class inside the
7232 class itself. Consider this parameter "unsubstituted",
7233 so that we will maintain the outer pack expansion. */
7234 arg_pack = NULL_TREE;
7240 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
7242 /* It's all-or-nothing with incomplete argument packs. */
7243 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7244 return error_mark_node;
7246 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7252 first_arg_pack = arg_pack;
7254 else if (len != my_len)
7256 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
7257 error ("mismatched argument pack lengths while expanding "
7261 error ("mismatched argument pack lengths while expanding "
7264 return error_mark_node;
7267 /* Keep track of the parameter packs and their corresponding
7269 packs = tree_cons (parm_pack, arg_pack, packs);
7270 TREE_TYPE (packs) = orig_arg;
7273 /* We can't substitute for this parameter pack. */
7274 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
7276 unsubstituted_packs);
7279 /* We cannot expand this expansion expression, because we don't have
7280 all of the argument packs we need. Substitute into the pattern
7281 and return a PACK_EXPANSION_*. The caller will need to deal with
7283 if (unsubstituted_packs)
7284 return make_pack_expansion (tsubst (pattern, args, complain,
7287 /* We could not find any argument packs that work. */
7289 return error_mark_node;
7291 /* For each argument in each argument pack, substitute into the
7293 result = make_tree_vec (len + incomplete);
7294 for (i = 0; i < len + incomplete; ++i)
7296 /* For parameter pack, change the substitution of the parameter
7297 pack to the ith argument in its argument pack, then expand
7299 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7301 tree parm = TREE_PURPOSE (pack);
7303 if (TREE_CODE (parm) == PARM_DECL)
7305 /* Select the Ith argument from the pack. */
7306 tree arg = make_node (ARGUMENT_PACK_SELECT);
7307 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
7308 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
7310 register_local_specialization (arg, parm);
7316 template_parm_level_and_index (parm, &level, &idx);
7320 /* Select the Ith argument from the pack. */
7321 value = make_node (ARGUMENT_PACK_SELECT);
7322 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
7323 ARGUMENT_PACK_SELECT_INDEX (value) = i;
7326 /* Update the corresponding argument. */
7327 TMPL_ARG (args, level, idx) = value;
7331 /* Substitute into the PATTERN with the altered arguments. */
7332 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
7333 TREE_VEC_ELT (result, i) =
7334 tsubst_expr (pattern, args, complain, in_decl,
7335 /*integral_constant_expression_p=*/false);
7337 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
7340 /* When we have incomplete argument packs, the last "expanded"
7341 result is itself a pack expansion, which allows us
7342 to deduce more arguments. */
7343 TREE_VEC_ELT (result, i) =
7344 make_pack_expansion (TREE_VEC_ELT (result, i));
7346 if (TREE_VEC_ELT (result, i) == error_mark_node)
7348 result = error_mark_node;
7353 /* Update ARGS to restore the substitution from parameter packs to
7354 their argument packs. */
7355 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7357 tree parm = TREE_PURPOSE (pack);
7359 if (TREE_CODE (parm) == PARM_DECL)
7360 register_local_specialization (TREE_TYPE (pack), parm);
7364 template_parm_level_and_index (parm, &level, &idx);
7366 /* Update the corresponding argument. */
7367 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
7368 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
7371 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
7378 /* Substitute ARGS into the vector or list of template arguments T. */
7381 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7384 int len = TREE_VEC_LENGTH (t);
7385 int need_new = 0, i, expanded_len_adjust = 0, out;
7386 tree *elts = (tree *) alloca (len * sizeof (tree));
7388 for (i = 0; i < len; i++)
7390 tree orig_arg = TREE_VEC_ELT (t, i);
7393 if (TREE_CODE (orig_arg) == TREE_VEC)
7394 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
7395 else if (PACK_EXPANSION_P (orig_arg))
7397 /* Substitute into an expansion expression. */
7398 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
7400 if (TREE_CODE (new_arg) == TREE_VEC)
7401 /* Add to the expanded length adjustment the number of
7402 expanded arguments. We subtract one from this
7403 measurement, because the argument pack expression
7404 itself is already counted as 1 in
7405 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
7406 the argument pack is empty. */
7407 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
7409 else if (ARGUMENT_PACK_P (orig_arg))
7411 /* Substitute into each of the arguments. */
7412 new_arg = make_node (TREE_CODE (orig_arg));
7414 SET_ARGUMENT_PACK_ARGS (
7416 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
7417 args, complain, in_decl));
7419 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
7420 new_arg = error_mark_node;
7422 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
7423 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
7425 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
7427 if (TREE_TYPE (new_arg) == error_mark_node)
7428 new_arg = error_mark_node;
7432 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
7434 if (new_arg == error_mark_node)
7435 return error_mark_node;
7438 if (new_arg != orig_arg)
7445 /* Make space for the expanded arguments coming from template
7447 t = make_tree_vec (len + expanded_len_adjust);
7448 for (i = 0, out = 0; i < len; i++)
7450 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
7451 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
7452 && TREE_CODE (elts[i]) == TREE_VEC)
7456 /* Now expand the template argument pack "in place". */
7457 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
7458 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
7462 TREE_VEC_ELT (t, out) = elts[i];
7470 /* Return the result of substituting ARGS into the template parameters
7471 given by PARMS. If there are m levels of ARGS and m + n levels of
7472 PARMS, then the result will contain n levels of PARMS. For
7473 example, if PARMS is `template <class T> template <class U>
7474 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
7475 result will be `template <int*, double, class V>'. */
7478 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
7483 /* When substituting into a template, we must set
7484 PROCESSING_TEMPLATE_DECL as the template parameters may be
7485 dependent if they are based on one-another, and the dependency
7486 predicates are short-circuit outside of templates. */
7487 ++processing_template_decl;
7489 for (new_parms = &r;
7490 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
7491 new_parms = &(TREE_CHAIN (*new_parms)),
7492 parms = TREE_CHAIN (parms))
7495 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
7498 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
7504 if (parms == error_mark_node)
7507 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
7509 if (tuple == error_mark_node)
7512 default_value = TREE_PURPOSE (tuple);
7513 parm_decl = TREE_VALUE (tuple);
7515 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
7516 if (TREE_CODE (parm_decl) == PARM_DECL
7517 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
7518 parm_decl = error_mark_node;
7519 default_value = tsubst_template_arg (default_value, args,
7520 complain, NULL_TREE);
7522 tuple = build_tree_list (default_value, parm_decl);
7523 TREE_VEC_ELT (new_vec, i) = tuple;
7527 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
7528 - TMPL_ARGS_DEPTH (args)),
7529 new_vec, NULL_TREE);
7532 --processing_template_decl;
7537 /* Substitute the ARGS into the indicated aggregate (or enumeration)
7538 type T. If T is not an aggregate or enumeration type, it is
7539 handled as if by tsubst. IN_DECL is as for tsubst. If
7540 ENTERING_SCOPE is nonzero, T is the context for a template which
7541 we are presently tsubst'ing. Return the substituted value. */
7544 tsubst_aggr_type (tree t,
7546 tsubst_flags_t complain,
7553 switch (TREE_CODE (t))
7556 if (TYPE_PTRMEMFUNC_P (t))
7557 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
7559 /* Else fall through. */
7562 if (TYPE_TEMPLATE_INFO (t))
7567 bool saved_skip_evaluation;
7569 /* In "sizeof(X<I>)" we need to evaluate "I". */
7570 saved_skip_evaluation = skip_evaluation;
7571 skip_evaluation = false;
7573 /* First, determine the context for the type we are looking
7575 context = TYPE_CONTEXT (t);
7577 context = tsubst_aggr_type (context, args, complain,
7578 in_decl, /*entering_scope=*/1);
7580 /* Then, figure out what arguments are appropriate for the
7581 type we are trying to find. For example, given:
7583 template <class T> struct S;
7584 template <class T, class U> void f(T, U) { S<U> su; }
7586 and supposing that we are instantiating f<int, double>,
7587 then our ARGS will be {int, double}, but, when looking up
7588 S we only want {double}. */
7589 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
7591 if (argvec == error_mark_node)
7592 r = error_mark_node;
7595 r = lookup_template_class (t, argvec, in_decl, context,
7596 entering_scope, complain);
7597 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7600 skip_evaluation = saved_skip_evaluation;
7605 /* This is not a template type, so there's nothing to do. */
7609 return tsubst (t, args, complain, in_decl);
7613 /* Substitute into the default argument ARG (a default argument for
7614 FN), which has the indicated TYPE. */
7617 tsubst_default_argument (tree fn, tree type, tree arg)
7619 tree saved_class_ptr = NULL_TREE;
7620 tree saved_class_ref = NULL_TREE;
7622 /* This default argument came from a template. Instantiate the
7623 default argument here, not in tsubst. In the case of
7632 we must be careful to do name lookup in the scope of S<T>,
7633 rather than in the current class. */
7634 push_access_scope (fn);
7635 /* The "this" pointer is not valid in a default argument. */
7638 saved_class_ptr = current_class_ptr;
7639 cp_function_chain->x_current_class_ptr = NULL_TREE;
7640 saved_class_ref = current_class_ref;
7641 cp_function_chain->x_current_class_ref = NULL_TREE;
7644 push_deferring_access_checks(dk_no_deferred);
7645 /* The default argument expression may cause implicitly defined
7646 member functions to be synthesized, which will result in garbage
7647 collection. We must treat this situation as if we were within
7648 the body of function so as to avoid collecting live data on the
7651 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
7652 tf_warning_or_error, NULL_TREE,
7653 /*integral_constant_expression_p=*/false);
7655 pop_deferring_access_checks();
7657 /* Restore the "this" pointer. */
7660 cp_function_chain->x_current_class_ptr = saved_class_ptr;
7661 cp_function_chain->x_current_class_ref = saved_class_ref;
7664 pop_access_scope (fn);
7666 /* Make sure the default argument is reasonable. */
7667 arg = check_default_argument (type, arg);
7672 /* Substitute into all the default arguments for FN. */
7675 tsubst_default_arguments (tree fn)
7680 tmpl_args = DECL_TI_ARGS (fn);
7682 /* If this function is not yet instantiated, we certainly don't need
7683 its default arguments. */
7684 if (uses_template_parms (tmpl_args))
7687 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
7689 arg = TREE_CHAIN (arg))
7690 if (TREE_PURPOSE (arg))
7691 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
7693 TREE_PURPOSE (arg));
7696 /* Substitute the ARGS into the T, which is a _DECL. Return the
7697 result of the substitution. Issue error and warning messages under
7698 control of COMPLAIN. */
7701 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
7703 location_t saved_loc;
7707 /* Set the filename and linenumber to improve error-reporting. */
7708 saved_loc = input_location;
7709 input_location = DECL_SOURCE_LOCATION (t);
7711 switch (TREE_CODE (t))
7715 /* We can get here when processing a member function template,
7716 member class template, and template template parameter of
7717 a template class. */
7718 tree decl = DECL_TEMPLATE_RESULT (t);
7723 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7725 /* Template template parameter is treated here. */
7726 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7727 if (new_type == error_mark_node)
7728 return error_mark_node;
7731 TREE_CHAIN (r) = NULL_TREE;
7732 TREE_TYPE (r) = new_type;
7733 DECL_TEMPLATE_RESULT (r)
7734 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
7735 DECL_TEMPLATE_PARMS (r)
7736 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
7738 TYPE_NAME (new_type) = r;
7742 /* We might already have an instance of this template.
7743 The ARGS are for the surrounding class type, so the
7744 full args contain the tsubst'd args for the context,
7745 plus the innermost args from the template decl. */
7746 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
7747 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
7748 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
7749 /* Because this is a template, the arguments will still be
7750 dependent, even after substitution. If
7751 PROCESSING_TEMPLATE_DECL is not set, the dependency
7752 predicates will short-circuit. */
7753 ++processing_template_decl;
7754 full_args = tsubst_template_args (tmpl_args, args,
7756 --processing_template_decl;
7757 if (full_args == error_mark_node)
7758 return error_mark_node;
7760 /* tsubst_template_args doesn't copy the vector if
7761 nothing changed. But, *something* should have
7763 gcc_assert (full_args != tmpl_args);
7765 spec = retrieve_specialization (t, full_args,
7766 /*class_specializations_p=*/true);
7767 if (spec != NULL_TREE)
7773 /* Make a new template decl. It will be similar to the
7774 original, but will record the current template arguments.
7775 We also create a new function declaration, which is just
7776 like the old one, but points to this new template, rather
7777 than the old one. */
7779 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
7780 TREE_CHAIN (r) = NULL_TREE;
7782 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
7784 if (TREE_CODE (decl) == TYPE_DECL)
7787 ++processing_template_decl;
7788 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7789 --processing_template_decl;
7790 if (new_type == error_mark_node)
7791 return error_mark_node;
7793 TREE_TYPE (r) = new_type;
7794 CLASSTYPE_TI_TEMPLATE (new_type) = r;
7795 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
7796 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
7797 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
7802 ++processing_template_decl;
7803 new_decl = tsubst (decl, args, complain, in_decl);
7804 --processing_template_decl;
7805 if (new_decl == error_mark_node)
7806 return error_mark_node;
7808 DECL_TEMPLATE_RESULT (r) = new_decl;
7809 DECL_TI_TEMPLATE (new_decl) = r;
7810 TREE_TYPE (r) = TREE_TYPE (new_decl);
7811 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
7812 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
7815 SET_DECL_IMPLICIT_INSTANTIATION (r);
7816 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
7817 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
7819 /* The template parameters for this new template are all the
7820 template parameters for the old template, except the
7821 outermost level of parameters. */
7822 DECL_TEMPLATE_PARMS (r)
7823 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
7826 if (PRIMARY_TEMPLATE_P (t))
7827 DECL_PRIMARY_TEMPLATE (r) = r;
7829 if (TREE_CODE (decl) != TYPE_DECL)
7830 /* Record this non-type partial instantiation. */
7831 register_specialization (r, t,
7832 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
7840 tree argvec = NULL_TREE;
7848 /* Nobody should be tsubst'ing into non-template functions. */
7849 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
7851 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
7856 /* If T is not dependent, just return it. We have to
7857 increment PROCESSING_TEMPLATE_DECL because
7858 value_dependent_expression_p assumes that nothing is
7859 dependent when PROCESSING_TEMPLATE_DECL is zero. */
7860 ++processing_template_decl;
7861 dependent_p = value_dependent_expression_p (t);
7862 --processing_template_decl;
7866 /* Calculate the most general template of which R is a
7867 specialization, and the complete set of arguments used to
7869 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
7870 argvec = tsubst_template_args (DECL_TI_ARGS
7871 (DECL_TEMPLATE_RESULT (gen_tmpl)),
7872 args, complain, in_decl);
7874 /* Check to see if we already have this specialization. */
7875 spec = retrieve_specialization (gen_tmpl, argvec,
7876 /*class_specializations_p=*/false);
7884 /* We can see more levels of arguments than parameters if
7885 there was a specialization of a member template, like
7888 template <class T> struct S { template <class U> void f(); }
7889 template <> template <class U> void S<int>::f(U);
7891 Here, we'll be substituting into the specialization,
7892 because that's where we can find the code we actually
7893 want to generate, but we'll have enough arguments for
7894 the most general template.
7896 We also deal with the peculiar case:
7898 template <class T> struct S {
7899 template <class U> friend void f();
7901 template <class U> void f() {}
7903 template void f<double>();
7905 Here, the ARGS for the instantiation of will be {int,
7906 double}. But, we only need as many ARGS as there are
7907 levels of template parameters in CODE_PATTERN. We are
7908 careful not to get fooled into reducing the ARGS in
7911 template <class T> struct S { template <class U> void f(U); }
7912 template <class T> template <> void S<T>::f(int) {}
7914 which we can spot because the pattern will be a
7915 specialization in this case. */
7916 args_depth = TMPL_ARGS_DEPTH (args);
7918 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
7919 if (args_depth > parms_depth
7920 && !DECL_TEMPLATE_SPECIALIZATION (t))
7921 args = get_innermost_template_args (args, parms_depth);
7925 /* This special case arises when we have something like this:
7927 template <class T> struct S {
7928 friend void f<int>(int, double);
7931 Here, the DECL_TI_TEMPLATE for the friend declaration
7932 will be an IDENTIFIER_NODE. We are being called from
7933 tsubst_friend_function, and we want only to create a
7934 new decl (R) with appropriate types so that we can call
7935 determine_specialization. */
7936 gen_tmpl = NULL_TREE;
7939 if (DECL_CLASS_SCOPE_P (t))
7941 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
7945 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
7946 complain, t, /*entering_scope=*/1);
7951 ctx = DECL_CONTEXT (t);
7953 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7954 if (type == error_mark_node)
7955 return error_mark_node;
7957 /* We do NOT check for matching decls pushed separately at this
7958 point, as they may not represent instantiations of this
7959 template, and in any case are considered separate under the
7962 DECL_USE_TEMPLATE (r) = 0;
7963 TREE_TYPE (r) = type;
7964 /* Clear out the mangled name and RTL for the instantiation. */
7965 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
7966 SET_DECL_RTL (r, NULL_RTX);
7967 DECL_INITIAL (r) = NULL_TREE;
7968 DECL_CONTEXT (r) = ctx;
7970 if (member && DECL_CONV_FN_P (r))
7971 /* Type-conversion operator. Reconstruct the name, in
7972 case it's the name of one of the template's parameters. */
7973 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
7975 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
7977 DECL_RESULT (r) = NULL_TREE;
7979 TREE_STATIC (r) = 0;
7980 TREE_PUBLIC (r) = TREE_PUBLIC (t);
7981 DECL_EXTERNAL (r) = 1;
7982 /* If this is an instantiation of a function with internal
7983 linkage, we already know what object file linkage will be
7984 assigned to the instantiation. */
7985 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
7986 DECL_DEFER_OUTPUT (r) = 0;
7987 TREE_CHAIN (r) = NULL_TREE;
7988 DECL_PENDING_INLINE_INFO (r) = 0;
7989 DECL_PENDING_INLINE_P (r) = 0;
7990 DECL_SAVED_TREE (r) = NULL_TREE;
7992 if (DECL_CLONED_FUNCTION (r))
7994 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
7996 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
7997 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
8000 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
8001 this in the special friend case mentioned above where
8002 GEN_TMPL is NULL. */
8005 DECL_TEMPLATE_INFO (r)
8006 = tree_cons (gen_tmpl, argvec, NULL_TREE);
8007 SET_DECL_IMPLICIT_INSTANTIATION (r);
8008 register_specialization (r, gen_tmpl, argvec, false);
8010 /* We're not supposed to instantiate default arguments
8011 until they are called, for a template. But, for a
8014 template <class T> void f ()
8015 { extern void g(int i = T()); }
8017 we should do the substitution when the template is
8018 instantiated. We handle the member function case in
8019 instantiate_class_template since the default arguments
8020 might refer to other members of the class. */
8022 && !PRIMARY_TEMPLATE_P (gen_tmpl)
8023 && !uses_template_parms (argvec))
8024 tsubst_default_arguments (r);
8027 DECL_TEMPLATE_INFO (r) = NULL_TREE;
8029 /* Copy the list of befriending classes. */
8030 for (friends = &DECL_BEFRIENDING_CLASSES (r);
8032 friends = &TREE_CHAIN (*friends))
8034 *friends = copy_node (*friends);
8035 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
8040 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
8042 maybe_retrofit_in_chrg (r);
8043 if (DECL_CONSTRUCTOR_P (r))
8044 grok_ctor_properties (ctx, r);
8045 /* If this is an instantiation of a member template, clone it.
8046 If it isn't, that'll be handled by
8047 clone_constructors_and_destructors. */
8048 if (PRIMARY_TEMPLATE_P (gen_tmpl))
8049 clone_function_decl (r, /*update_method_vec_p=*/0);
8051 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r))
8052 && !grok_op_properties (r, (complain & tf_error) != 0))
8053 return error_mark_node;
8055 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
8056 SET_DECL_FRIEND_CONTEXT (r,
8057 tsubst (DECL_FRIEND_CONTEXT (t),
8058 args, complain, in_decl));
8060 /* Possibly limit visibility based on template args. */
8061 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8062 if (DECL_VISIBILITY_SPECIFIED (t))
8064 DECL_VISIBILITY_SPECIFIED (r) = 0;
8066 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8068 determine_visibility (r);
8070 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8071 args, complain, in_decl);
8077 tree type = NULL_TREE;
8079 tree expanded_types = NULL_TREE;
8080 tree prev_r = NULL_TREE;
8081 tree first_r = NULL_TREE;
8083 if (FUNCTION_PARAMETER_PACK_P (t))
8085 /* If there is a local specialization that isn't a
8086 parameter pack, it means that we're doing a "simple"
8087 substitution from inside tsubst_pack_expansion. Just
8088 return the local specialization (which will be a single
8090 tree spec = NULL_TREE;
8091 if (local_specializations)
8092 spec = retrieve_local_specialization (t);
8094 && TREE_CODE (spec) == PARM_DECL
8095 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
8098 /* Expand the TYPE_PACK_EXPANSION that provides the types for
8099 the parameters in this function parameter pack. */
8100 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
8102 if (TREE_CODE (expanded_types) == TREE_VEC)
8104 len = TREE_VEC_LENGTH (expanded_types);
8106 /* Zero-length parameter packs are boring. Just substitute
8109 return tsubst (TREE_CHAIN (t), args, complain,
8114 /* All we did was update the type. Make a note of that. */
8115 type = expanded_types;
8116 expanded_types = NULL_TREE;
8120 /* Loop through all of the parameter's we'll build. When T is
8121 a function parameter pack, LEN is the number of expanded
8122 types in EXPANDED_TYPES; otherwise, LEN is 1. */
8124 for (i = 0; i < len; ++i)
8128 if (DECL_TEMPLATE_PARM_P (t))
8129 SET_DECL_TEMPLATE_PARM_P (r);
8132 /* We're on the Ith parameter of the function parameter
8135 /* Get the Ith type. */
8136 type = TREE_VEC_ELT (expanded_types, i);
8139 /* Rename the parameter to include the index. */
8141 make_ith_pack_parameter_name (DECL_NAME (r), i);
8144 /* We're dealing with a normal parameter. */
8145 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8147 type = type_decays_to (type);
8148 TREE_TYPE (r) = type;
8149 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8151 if (DECL_INITIAL (r))
8153 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
8154 DECL_INITIAL (r) = TREE_TYPE (r);
8156 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
8160 DECL_CONTEXT (r) = NULL_TREE;
8162 if (!DECL_TEMPLATE_PARM_P (r))
8163 DECL_ARG_TYPE (r) = type_passed_as (type);
8165 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8166 args, complain, in_decl);
8168 /* Keep track of the first new parameter we
8169 generate. That's what will be returned to the
8174 /* Build a proper chain of parameters when substituting
8175 into a function parameter pack. */
8177 TREE_CHAIN (prev_r) = r;
8181 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
8182 complain, TREE_CHAIN (t));
8184 /* FIRST_R contains the start of the chain we've built. */
8194 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8195 if (type == error_mark_node)
8196 return error_mark_node;
8197 TREE_TYPE (r) = type;
8198 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8200 /* DECL_INITIAL gives the number of bits in a bit-field. */
8202 = tsubst_expr (DECL_INITIAL (t), args,
8204 /*integral_constant_expression_p=*/true);
8205 /* We don't have to set DECL_CONTEXT here; it is set by
8206 finish_member_declaration. */
8207 TREE_CHAIN (r) = NULL_TREE;
8208 if (VOID_TYPE_P (type))
8209 error ("instantiation of %q+D as type %qT", r, type);
8211 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8212 args, complain, in_decl);
8217 /* We reach here only for member using decls. */
8218 if (DECL_DEPENDENT_P (t))
8220 r = do_class_using_decl
8221 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
8222 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
8224 r = error_mark_node;
8229 TREE_CHAIN (r) = NULL_TREE;
8236 tree argvec = NULL_TREE;
8237 tree gen_tmpl = NULL_TREE;
8239 tree tmpl = NULL_TREE;
8241 tree type = NULL_TREE;
8244 if (TREE_CODE (t) == TYPE_DECL
8245 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
8247 /* If this is the canonical decl, we don't have to
8248 mess with instantiations, and often we can't (for
8249 typename, template type parms and such). Note that
8250 TYPE_NAME is not correct for the above test if
8251 we've copied the type for a typedef. */
8252 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8253 if (type == error_mark_node)
8254 return error_mark_node;
8255 r = TYPE_NAME (type);
8259 /* Check to see if we already have the specialization we
8262 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
8264 /* T is a static data member or namespace-scope entity.
8265 We have to substitute into namespace-scope variables
8266 (even though such entities are never templates) because
8269 template <class T> void f() { extern T t; }
8271 where the entity referenced is not known until
8272 instantiation time. */
8274 ctx = DECL_CONTEXT (t);
8275 if (DECL_CLASS_SCOPE_P (t))
8277 ctx = tsubst_aggr_type (ctx, args,
8279 in_decl, /*entering_scope=*/1);
8280 /* If CTX is unchanged, then T is in fact the
8281 specialization we want. That situation occurs when
8282 referencing a static data member within in its own
8283 class. We can use pointer equality, rather than
8284 same_type_p, because DECL_CONTEXT is always
8286 if (ctx == DECL_CONTEXT (t))
8292 tmpl = DECL_TI_TEMPLATE (t);
8293 gen_tmpl = most_general_template (tmpl);
8294 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
8295 spec = (retrieve_specialization
8297 /*class_specializations_p=*/false));
8302 /* A local variable. */
8304 /* Subsequent calls to pushdecl will fill this in. */
8306 spec = retrieve_local_specialization (t);
8308 /* If we already have the specialization we need, there is
8309 nothing more to do. */
8316 /* Create a new node for the specialization we need. */
8318 if (type == NULL_TREE)
8319 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8320 if (TREE_CODE (r) == VAR_DECL)
8322 /* Even if the original location is out of scope, the
8323 newly substituted one is not. */
8324 DECL_DEAD_FOR_LOCAL (r) = 0;
8325 DECL_INITIALIZED_P (r) = 0;
8326 DECL_TEMPLATE_INSTANTIATED (r) = 0;
8327 if (type == error_mark_node)
8328 return error_mark_node;
8329 if (TREE_CODE (type) == FUNCTION_TYPE)
8331 /* It may seem that this case cannot occur, since:
8336 declares a function, not a variable. However:
8339 template <typename T> void g() { T t; }
8340 template void g<f>();
8342 is an attempt to declare a variable with function
8344 error ("variable %qD has function type",
8345 /* R is not yet sufficiently initialized, so we
8346 just use its name. */
8348 return error_mark_node;
8350 type = complete_type (type);
8351 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
8352 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
8353 type = check_var_type (DECL_NAME (r), type);
8355 if (DECL_HAS_VALUE_EXPR_P (t))
8357 tree ve = DECL_VALUE_EXPR (t);
8358 ve = tsubst_expr (ve, args, complain, in_decl,
8359 /*constant_expression_p=*/false);
8360 SET_DECL_VALUE_EXPR (r, ve);
8363 else if (DECL_SELF_REFERENCE_P (t))
8364 SET_DECL_SELF_REFERENCE_P (r);
8365 TREE_TYPE (r) = type;
8366 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8367 DECL_CONTEXT (r) = ctx;
8368 /* Clear out the mangled name and RTL for the instantiation. */
8369 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8370 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8371 SET_DECL_RTL (r, NULL_RTX);
8372 /* The initializer must not be expanded until it is required;
8374 DECL_INITIAL (r) = NULL_TREE;
8375 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8376 SET_DECL_RTL (r, NULL_RTX);
8377 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
8378 if (TREE_CODE (r) == VAR_DECL)
8380 /* Possibly limit visibility based on template args. */
8381 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8382 if (DECL_VISIBILITY_SPECIFIED (t))
8384 DECL_VISIBILITY_SPECIFIED (r) = 0;
8386 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8388 determine_visibility (r);
8390 /* Preserve a typedef that names a type. */
8391 else if (TREE_CODE (r) == TYPE_DECL
8392 && DECL_ORIGINAL_TYPE (t)
8393 && type != error_mark_node)
8395 DECL_ORIGINAL_TYPE (r) = tsubst (DECL_ORIGINAL_TYPE (t),
8396 args, complain, in_decl);
8397 TREE_TYPE (r) = type = build_variant_type_copy (type);
8398 TYPE_NAME (type) = r;
8403 /* A static data member declaration is always marked
8404 external when it is declared in-class, even if an
8405 initializer is present. We mimic the non-template
8407 DECL_EXTERNAL (r) = 1;
8409 register_specialization (r, gen_tmpl, argvec, false);
8410 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
8411 SET_DECL_IMPLICIT_INSTANTIATION (r);
8414 register_local_specialization (r, t);
8416 TREE_CHAIN (r) = NULL_TREE;
8418 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
8419 (int) ATTR_FLAG_TYPE_IN_PLACE,
8420 args, complain, in_decl);
8429 /* Restore the file and line information. */
8430 input_location = saved_loc;
8435 /* Substitute into the ARG_TYPES of a function type. */
8438 tsubst_arg_types (tree arg_types,
8440 tsubst_flags_t complain,
8443 tree remaining_arg_types;
8444 tree type = NULL_TREE;
8446 tree expanded_args = NULL_TREE;
8449 if (!arg_types || arg_types == void_list_node)
8452 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
8453 args, complain, in_decl);
8454 if (remaining_arg_types == error_mark_node)
8455 return error_mark_node;
8457 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
8459 /* For a pack expansion, perform substitution on the
8460 entire expression. Later on, we'll handle the arguments
8462 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
8463 args, complain, in_decl);
8465 if (TREE_CODE (expanded_args) == TREE_VEC)
8466 /* So that we'll spin through the parameters, one by one. */
8467 i = TREE_VEC_LENGTH (expanded_args);
8470 /* We only partially substituted into the parameter
8471 pack. Our type is TYPE_PACK_EXPANSION. */
8472 type = expanded_args;
8473 expanded_args = NULL_TREE;
8481 type = TREE_VEC_ELT (expanded_args, i);
8483 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
8485 if (type == error_mark_node)
8486 return error_mark_node;
8487 if (VOID_TYPE_P (type))
8489 if (complain & tf_error)
8491 error ("invalid parameter type %qT", type);
8493 error ("in declaration %q+D", in_decl);
8495 return error_mark_node;
8498 /* Do array-to-pointer, function-to-pointer conversion, and ignore
8499 top-level qualifiers as required. */
8500 type = TYPE_MAIN_VARIANT (type_decays_to (type));
8502 /* We do not substitute into default arguments here. The standard
8503 mandates that they be instantiated only when needed, which is
8504 done in build_over_call. */
8505 default_arg = TREE_PURPOSE (arg_types);
8507 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
8509 /* We've instantiated a template before its default arguments
8510 have been parsed. This can happen for a nested template
8511 class, and is not an error unless we require the default
8512 argument in a call of this function. */
8513 remaining_arg_types =
8514 tree_cons (default_arg, type, remaining_arg_types);
8515 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
8516 remaining_arg_types);
8519 remaining_arg_types =
8520 hash_tree_cons (default_arg, type, remaining_arg_types);
8523 return remaining_arg_types;
8526 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
8527 *not* handle the exception-specification for FNTYPE, because the
8528 initial substitution of explicitly provided template parameters
8529 during argument deduction forbids substitution into the
8530 exception-specification:
8534 All references in the function type of the function template to the
8535 corresponding template parameters are replaced by the specified tem-
8536 plate argument values. If a substitution in a template parameter or
8537 in the function type of the function template results in an invalid
8538 type, type deduction fails. [Note: The equivalent substitution in
8539 exception specifications is done only when the function is instanti-
8540 ated, at which point a program is ill-formed if the substitution
8541 results in an invalid type.] */
8544 tsubst_function_type (tree t,
8546 tsubst_flags_t complain,
8553 /* The TYPE_CONTEXT is not used for function/method types. */
8554 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
8556 /* Substitute the return type. */
8557 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8558 if (return_type == error_mark_node)
8559 return error_mark_node;
8560 /* The standard does not presently indicate that creation of a
8561 function type with an invalid return type is a deduction failure.
8562 However, that is clearly analogous to creating an array of "void"
8563 or a reference to a reference. This is core issue #486. */
8564 if (TREE_CODE (return_type) == ARRAY_TYPE
8565 || TREE_CODE (return_type) == FUNCTION_TYPE)
8567 if (complain & tf_error)
8569 if (TREE_CODE (return_type) == ARRAY_TYPE)
8570 error ("function returning an array");
8572 error ("function returning a function");
8574 return error_mark_node;
8577 /* Substitute the argument types. */
8578 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
8580 if (arg_types == error_mark_node)
8581 return error_mark_node;
8583 if (TYPE_QUALS (return_type) != TYPE_UNQUALIFIED
8584 && in_decl != NULL_TREE
8585 && !TREE_NO_WARNING (in_decl)
8586 && (SCALAR_TYPE_P (return_type) || VOID_TYPE_P (return_type)))
8587 warning (OPT_Wreturn_type,
8588 "type qualifiers ignored on function return type");
8590 /* Construct a new type node and return it. */
8591 if (TREE_CODE (t) == FUNCTION_TYPE)
8592 fntype = build_function_type (return_type, arg_types);
8595 tree r = TREE_TYPE (TREE_VALUE (arg_types));
8596 if (! IS_AGGR_TYPE (r))
8600 Type deduction may fail for any of the following
8603 -- Attempting to create "pointer to member of T" when T
8604 is not a class type. */
8605 if (complain & tf_error)
8606 error ("creating pointer to member function of non-class type %qT",
8608 return error_mark_node;
8611 fntype = build_method_type_directly (r, return_type,
8612 TREE_CHAIN (arg_types));
8614 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
8615 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
8620 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
8621 ARGS into that specification, and return the substituted
8622 specification. If there is no specification, return NULL_TREE. */
8625 tsubst_exception_specification (tree fntype,
8627 tsubst_flags_t complain,
8633 specs = TYPE_RAISES_EXCEPTIONS (fntype);
8634 new_specs = NULL_TREE;
8637 if (! TREE_VALUE (specs))
8644 tree expanded_specs = NULL_TREE;
8646 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
8648 /* Expand the pack expansion type. */
8649 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
8652 len = TREE_VEC_LENGTH (expanded_specs);
8655 for (i = 0; i < len; ++i)
8658 spec = TREE_VEC_ELT (expanded_specs, i);
8660 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
8661 if (spec == error_mark_node)
8663 new_specs = add_exception_specifier (new_specs, spec,
8667 specs = TREE_CHAIN (specs);
8673 /* Take the tree structure T and replace template parameters used
8674 therein with the argument vector ARGS. IN_DECL is an associated
8675 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
8676 Issue error and warning messages under control of COMPLAIN. Note
8677 that we must be relatively non-tolerant of extensions here, in
8678 order to preserve conformance; if we allow substitutions that
8679 should not be allowed, we may allow argument deductions that should
8680 not succeed, and therefore report ambiguous overload situations
8681 where there are none. In theory, we could allow the substitution,
8682 but indicate that it should have failed, and allow our caller to
8683 make sure that the right thing happens, but we don't try to do this
8686 This function is used for dealing with types, decls and the like;
8687 for expressions, use tsubst_expr or tsubst_copy. */
8690 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8694 if (t == NULL_TREE || t == error_mark_node
8695 || t == integer_type_node
8696 || t == void_type_node
8697 || t == char_type_node
8698 || t == unknown_type_node
8699 || TREE_CODE (t) == NAMESPACE_DECL)
8703 return tsubst_decl (t, args, complain);
8705 if (TREE_CODE (t) == IDENTIFIER_NODE)
8706 type = IDENTIFIER_TYPE_VALUE (t);
8708 type = TREE_TYPE (t);
8710 gcc_assert (type != unknown_type_node);
8712 /* Reuse typedefs. We need to do this to handle dependent attributes,
8713 such as attribute aligned. */
8716 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
8718 tree decl = TYPE_NAME (t);
8720 if (DECL_CLASS_SCOPE_P (decl)
8721 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl)))
8723 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
8724 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
8725 r = retrieve_specialization (tmpl, gen_args, false);
8727 else if (DECL_FUNCTION_SCOPE_P (decl))
8728 r = retrieve_local_specialization (decl);
8735 r = cp_build_qualified_type_real
8736 (r, cp_type_quals (t) | cp_type_quals (r),
8737 complain | tf_ignore_bad_quals);
8740 /* Else we must be instantiating the typedef, so fall through. */
8744 && TREE_CODE (t) != TYPENAME_TYPE
8745 && TREE_CODE (t) != IDENTIFIER_NODE
8746 && TREE_CODE (t) != FUNCTION_TYPE
8747 && TREE_CODE (t) != METHOD_TYPE)
8748 type = tsubst (type, args, complain, in_decl);
8749 if (type == error_mark_node)
8750 return error_mark_node;
8752 switch (TREE_CODE (t))
8757 return tsubst_aggr_type (t, args, complain, in_decl,
8758 /*entering_scope=*/0);
8761 case IDENTIFIER_NODE:
8773 if (t == integer_type_node)
8776 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
8777 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
8781 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
8783 max = tsubst_expr (omax, args, complain, in_decl,
8784 /*integral_constant_expression_p=*/false);
8785 max = fold_decl_constant_value (max);
8787 if (TREE_CODE (max) != INTEGER_CST
8788 && TREE_CODE (max) != TEMPLATE_PARM_INDEX
8789 && !at_function_scope_p ())
8791 if (complain & tf_error)
8792 error ("array bound is not an integer constant");
8793 return error_mark_node;
8798 Type deduction may fail for any of the following
8801 Attempting to create an array with a size that is
8802 zero or negative. */
8803 if (integer_zerop (max) && !(complain & tf_error))
8804 /* We must fail if performing argument deduction (as
8805 indicated by the state of complain), so that
8806 another substitution can be found. */
8807 return error_mark_node;
8808 else if (TREE_CODE (max) == INTEGER_CST
8809 && INT_CST_LT (max, integer_zero_node))
8811 if (complain & tf_error)
8812 error ("creating array with negative size (%qE)", max);
8814 return error_mark_node;
8817 return compute_array_index_type (NULL_TREE, max);
8820 case TEMPLATE_TYPE_PARM:
8821 case TEMPLATE_TEMPLATE_PARM:
8822 case BOUND_TEMPLATE_TEMPLATE_PARM:
8823 case TEMPLATE_PARM_INDEX:
8828 tree arg = NULL_TREE;
8832 gcc_assert (TREE_VEC_LENGTH (args) > 0);
8833 template_parm_level_and_index (t, &level, &idx);
8835 levels = TMPL_ARGS_DEPTH (args);
8836 if (level <= levels)
8838 arg = TMPL_ARG (args, level, idx);
8840 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
8841 /* See through ARGUMENT_PACK_SELECT arguments. */
8842 arg = ARGUMENT_PACK_SELECT_ARG (arg);
8845 if (arg == error_mark_node)
8846 return error_mark_node;
8847 else if (arg != NULL_TREE)
8849 if (ARGUMENT_PACK_P (arg))
8850 /* If ARG is an argument pack, we don't actually want to
8851 perform a substitution here, because substitutions
8852 for argument packs are only done
8853 element-by-element. We can get to this point when
8854 substituting the type of a non-type template
8855 parameter pack, when that type actually contains
8856 template parameter packs from an outer template, e.g.,
8858 template<typename... Types> struct A {
8859 template<Types... Values> struct B { };
8863 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
8866 gcc_assert (TYPE_P (arg));
8868 /* cv-quals from the template are discarded when
8869 substituting in a function or reference type. */
8870 if (TREE_CODE (arg) == FUNCTION_TYPE
8871 || TREE_CODE (arg) == METHOD_TYPE
8872 || TREE_CODE (arg) == REFERENCE_TYPE)
8873 quals = cp_type_quals (arg);
8875 quals = cp_type_quals (arg) | cp_type_quals (t);
8877 return cp_build_qualified_type_real
8878 (arg, quals, complain | tf_ignore_bad_quals);
8880 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
8882 /* We are processing a type constructed from a
8883 template template parameter. */
8884 tree argvec = tsubst (TYPE_TI_ARGS (t),
8885 args, complain, in_decl);
8886 if (argvec == error_mark_node)
8887 return error_mark_node;
8889 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
8890 are resolving nested-types in the signature of a
8891 member function templates. Otherwise ARG is a
8892 TEMPLATE_DECL and is the real template to be
8894 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
8895 arg = TYPE_NAME (arg);
8897 r = lookup_template_class (arg,
8900 /*entering_scope=*/0,
8902 return cp_build_qualified_type_real
8903 (r, TYPE_QUALS (t), complain);
8906 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
8911 /* This can happen during the attempted tsubst'ing in
8912 unify. This means that we don't yet have any information
8913 about the template parameter in question. */
8916 /* If we get here, we must have been looking at a parm for a
8917 more deeply nested template. Make a new version of this
8918 template parameter, but with a lower level. */
8919 switch (TREE_CODE (t))
8921 case TEMPLATE_TYPE_PARM:
8922 case TEMPLATE_TEMPLATE_PARM:
8923 case BOUND_TEMPLATE_TEMPLATE_PARM:
8924 if (cp_type_quals (t))
8926 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
8927 r = cp_build_qualified_type_real
8928 (r, cp_type_quals (t),
8929 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
8930 ? tf_ignore_bad_quals : 0));
8935 TEMPLATE_TYPE_PARM_INDEX (r)
8936 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
8937 r, levels, args, complain);
8938 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
8939 TYPE_MAIN_VARIANT (r) = r;
8940 TYPE_POINTER_TO (r) = NULL_TREE;
8941 TYPE_REFERENCE_TO (r) = NULL_TREE;
8943 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
8944 /* We have reduced the level of the template
8945 template parameter, but not the levels of its
8946 template parameters, so canonical_type_parameter
8947 will not be able to find the canonical template
8948 template parameter for this level. Thus, we
8949 require structural equality checking to compare
8950 TEMPLATE_TEMPLATE_PARMs. */
8951 SET_TYPE_STRUCTURAL_EQUALITY (r);
8952 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
8953 SET_TYPE_STRUCTURAL_EQUALITY (r);
8955 TYPE_CANONICAL (r) = canonical_type_parameter (r);
8957 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
8959 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
8961 if (argvec == error_mark_node)
8962 return error_mark_node;
8964 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
8965 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
8970 case TEMPLATE_PARM_INDEX:
8971 r = reduce_template_parm_level (t, type, levels, args, complain);
8983 tree purpose, value, chain;
8985 if (t == void_list_node)
8988 purpose = TREE_PURPOSE (t);
8991 purpose = tsubst (purpose, args, complain, in_decl);
8992 if (purpose == error_mark_node)
8993 return error_mark_node;
8995 value = TREE_VALUE (t);
8998 value = tsubst (value, args, complain, in_decl);
8999 if (value == error_mark_node)
9000 return error_mark_node;
9002 chain = TREE_CHAIN (t);
9003 if (chain && chain != void_type_node)
9005 chain = tsubst (chain, args, complain, in_decl);
9006 if (chain == error_mark_node)
9007 return error_mark_node;
9009 if (purpose == TREE_PURPOSE (t)
9010 && value == TREE_VALUE (t)
9011 && chain == TREE_CHAIN (t))
9013 return hash_tree_cons (purpose, value, chain);
9017 /* We should never be tsubsting a binfo. */
9021 /* A vector of template arguments. */
9023 return tsubst_template_args (t, args, complain, in_decl);
9026 case REFERENCE_TYPE:
9028 enum tree_code code;
9030 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
9033 code = TREE_CODE (t);
9038 Type deduction may fail for any of the following
9041 -- Attempting to create a pointer to reference type.
9042 -- Attempting to create a reference to a reference type or
9043 a reference to void.
9045 Core issue 106 says that creating a reference to a reference
9046 during instantiation is no longer a cause for failure. We
9047 only enforce this check in strict C++98 mode. */
9048 if ((TREE_CODE (type) == REFERENCE_TYPE
9049 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
9050 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
9052 static location_t last_loc;
9054 /* We keep track of the last time we issued this error
9055 message to avoid spewing a ton of messages during a
9056 single bad template instantiation. */
9057 if (complain & tf_error
9058 #ifdef USE_MAPPED_LOCATION
9059 && last_loc != input_location
9061 && (last_loc.line != input_line
9062 || last_loc.file != input_filename)
9066 if (TREE_CODE (type) == VOID_TYPE)
9067 error ("forming reference to void");
9069 error ("forming %s to reference type %qT",
9070 (code == POINTER_TYPE) ? "pointer" : "reference",
9072 last_loc = input_location;
9075 return error_mark_node;
9077 else if (code == POINTER_TYPE)
9079 r = build_pointer_type (type);
9080 if (TREE_CODE (type) == METHOD_TYPE)
9081 r = build_ptrmemfunc_type (r);
9083 else if (TREE_CODE (type) == REFERENCE_TYPE)
9084 /* In C++0x, during template argument substitution, when there is an
9085 attempt to create a reference to a reference type, reference
9086 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
9088 "If a template-argument for a template-parameter T names a type
9089 that is a reference to a type A, an attempt to create the type
9090 'lvalue reference to cv T' creates the type 'lvalue reference to
9091 A,' while an attempt to create the type type rvalue reference to
9092 cv T' creates the type T"
9094 r = cp_build_reference_type
9096 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
9098 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
9099 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
9101 if (r != error_mark_node)
9102 /* Will this ever be needed for TYPE_..._TO values? */
9109 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
9110 if (r == error_mark_node || !IS_AGGR_TYPE (r))
9114 Type deduction may fail for any of the following
9117 -- Attempting to create "pointer to member of T" when T
9118 is not a class type. */
9119 if (complain & tf_error)
9120 error ("creating pointer to member of non-class type %qT", r);
9121 return error_mark_node;
9123 if (TREE_CODE (type) == REFERENCE_TYPE)
9125 if (complain & tf_error)
9126 error ("creating pointer to member reference type %qT", type);
9127 return error_mark_node;
9129 if (TREE_CODE (type) == VOID_TYPE)
9131 if (complain & tf_error)
9132 error ("creating pointer to member of type void");
9133 return error_mark_node;
9135 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
9136 if (TREE_CODE (type) == FUNCTION_TYPE)
9138 /* The type of the implicit object parameter gets its
9139 cv-qualifiers from the FUNCTION_TYPE. */
9141 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
9142 cp_type_quals (type));
9144 method_type = build_method_type_directly (this_type,
9146 TYPE_ARG_TYPES (type));
9147 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
9148 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
9152 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
9161 fntype = tsubst_function_type (t, args, complain, in_decl);
9162 if (fntype == error_mark_node)
9163 return error_mark_node;
9165 /* Substitute the exception specification. */
9166 specs = tsubst_exception_specification (t, args, complain,
9168 if (specs == error_mark_node)
9169 return error_mark_node;
9171 fntype = build_exception_variant (fntype, specs);
9176 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
9177 if (domain == error_mark_node)
9178 return error_mark_node;
9180 /* As an optimization, we avoid regenerating the array type if
9181 it will obviously be the same as T. */
9182 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
9185 /* These checks should match the ones in grokdeclarator.
9189 The deduction may fail for any of the following reasons:
9191 -- Attempting to create an array with an element type that
9192 is void, a function type, or a reference type, or [DR337]
9193 an abstract class type. */
9194 if (TREE_CODE (type) == VOID_TYPE
9195 || TREE_CODE (type) == FUNCTION_TYPE
9196 || TREE_CODE (type) == REFERENCE_TYPE)
9198 if (complain & tf_error)
9199 error ("creating array of %qT", type);
9200 return error_mark_node;
9202 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
9204 if (complain & tf_error)
9205 error ("creating array of %qT, which is an abstract class type",
9207 return error_mark_node;
9210 r = build_cplus_array_type (type, domain);
9212 if (TYPE_USER_ALIGN (t))
9214 TYPE_ALIGN (r) = TYPE_ALIGN (t);
9215 TYPE_USER_ALIGN (r) = 1;
9224 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9225 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9227 if (e1 == error_mark_node || e2 == error_mark_node)
9228 return error_mark_node;
9230 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
9236 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9237 if (e == error_mark_node)
9238 return error_mark_node;
9240 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
9245 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9246 in_decl, /*entering_scope=*/1);
9247 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
9250 if (ctx == error_mark_node || f == error_mark_node)
9251 return error_mark_node;
9253 if (!IS_AGGR_TYPE (ctx))
9255 if (complain & tf_error)
9256 error ("%qT is not a class, struct, or union type", ctx);
9257 return error_mark_node;
9259 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
9261 /* Normally, make_typename_type does not require that the CTX
9262 have complete type in order to allow things like:
9264 template <class T> struct S { typename S<T>::X Y; };
9266 But, such constructs have already been resolved by this
9267 point, so here CTX really should have complete type, unless
9268 it's a partial instantiation. */
9269 ctx = complete_type (ctx);
9270 if (!COMPLETE_TYPE_P (ctx))
9272 if (complain & tf_error)
9273 cxx_incomplete_type_error (NULL_TREE, ctx);
9274 return error_mark_node;
9278 f = make_typename_type (ctx, f, typename_type,
9279 (complain & tf_error) | tf_keep_type_decl);
9280 if (f == error_mark_node)
9282 if (TREE_CODE (f) == TYPE_DECL)
9284 complain |= tf_ignore_bad_quals;
9288 if (TREE_CODE (f) != TYPENAME_TYPE)
9290 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
9291 error ("%qT resolves to %qT, which is not an enumeration type",
9293 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
9294 error ("%qT resolves to %qT, which is is not a class type",
9298 return cp_build_qualified_type_real
9299 (f, cp_type_quals (f) | cp_type_quals (t), complain);
9302 case UNBOUND_CLASS_TEMPLATE:
9304 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9305 in_decl, /*entering_scope=*/1);
9306 tree name = TYPE_IDENTIFIER (t);
9307 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
9309 if (ctx == error_mark_node || name == error_mark_node)
9310 return error_mark_node;
9313 parm_list = tsubst_template_parms (parm_list, args, complain);
9314 return make_unbound_class_template (ctx, name, parm_list, complain);
9324 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9325 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
9326 /*integral_constant_expression_p=*/false);
9327 if (e1 == error_mark_node || e2 == error_mark_node)
9328 return error_mark_node;
9330 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
9335 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9336 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9337 if (e1 == error_mark_node || e2 == error_mark_node)
9338 return error_mark_node;
9340 return build_qualified_name (/*type=*/NULL_TREE,
9341 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
9348 type = finish_typeof (tsubst_expr
9349 (TYPEOF_TYPE_EXPR (t), args,
9351 /*integral_constant_expression_p=*/false));
9352 return cp_build_qualified_type_real (type,
9354 | cp_type_quals (type),
9363 finish_decltype_type (tsubst_expr
9364 (DECLTYPE_TYPE_EXPR (t), args,
9366 /*integral_constant_expression_p=*/false),
9367 DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
9368 return cp_build_qualified_type_real (type,
9370 | cp_type_quals (type),
9374 case TYPE_ARGUMENT_PACK:
9375 case NONTYPE_ARGUMENT_PACK:
9377 tree r = make_node (TREE_CODE (t));
9379 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
9383 SET_ARGUMENT_PACK_ARGS (r, packed_out);
9385 /* For template nontype argument packs, also substitute into
9387 if (TREE_CODE (t) == NONTYPE_ARGUMENT_PACK)
9388 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
9395 sorry ("use of %qs in template",
9396 tree_code_name [(int) TREE_CODE (t)]);
9397 return error_mark_node;
9401 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
9402 type of the expression on the left-hand side of the "." or "->"
9406 tsubst_baselink (tree baselink, tree object_type,
9407 tree args, tsubst_flags_t complain, tree in_decl)
9410 tree qualifying_scope;
9413 tree template_args = 0;
9414 bool template_id_p = false;
9416 /* A baselink indicates a function from a base class. Both the
9417 BASELINK_ACCESS_BINFO and the base class referenced may
9418 indicate bases of the template class, rather than the
9419 instantiated class. In addition, lookups that were not
9420 ambiguous before may be ambiguous now. Therefore, we perform
9421 the lookup again. */
9422 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
9423 qualifying_scope = tsubst (qualifying_scope, args,
9425 fns = BASELINK_FUNCTIONS (baselink);
9426 optype = BASELINK_OPTYPE (baselink);
9427 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
9429 template_id_p = true;
9430 template_args = TREE_OPERAND (fns, 1);
9431 fns = TREE_OPERAND (fns, 0);
9433 template_args = tsubst_template_args (template_args, args,
9436 name = DECL_NAME (get_first_fn (fns));
9437 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
9439 /* If lookup found a single function, mark it as used at this
9440 point. (If it lookup found multiple functions the one selected
9441 later by overload resolution will be marked as used at that
9443 if (BASELINK_P (baselink))
9444 fns = BASELINK_FUNCTIONS (baselink);
9445 if (!template_id_p && !really_overloaded_fn (fns))
9446 mark_used (OVL_CURRENT (fns));
9448 /* Add back the template arguments, if present. */
9449 if (BASELINK_P (baselink) && template_id_p)
9450 BASELINK_FUNCTIONS (baselink)
9451 = build_nt (TEMPLATE_ID_EXPR,
9452 BASELINK_FUNCTIONS (baselink),
9454 /* Update the conversion operator type. */
9455 BASELINK_OPTYPE (baselink)
9456 = tsubst (optype, args, complain, in_decl);
9459 object_type = current_class_type;
9460 return adjust_result_of_qualified_name_lookup (baselink,
9465 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
9466 true if the qualified-id will be a postfix-expression in-and-of
9467 itself; false if more of the postfix-expression follows the
9468 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
9472 tsubst_qualified_id (tree qualified_id, tree args,
9473 tsubst_flags_t complain, tree in_decl,
9474 bool done, bool address_p)
9482 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
9484 /* Figure out what name to look up. */
9485 name = TREE_OPERAND (qualified_id, 1);
9486 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
9489 template_args = TREE_OPERAND (name, 1);
9491 template_args = tsubst_template_args (template_args, args,
9493 name = TREE_OPERAND (name, 0);
9497 is_template = false;
9498 template_args = NULL_TREE;
9501 /* Substitute into the qualifying scope. When there are no ARGS, we
9502 are just trying to simplify a non-dependent expression. In that
9503 case the qualifying scope may be dependent, and, in any case,
9504 substituting will not help. */
9505 scope = TREE_OPERAND (qualified_id, 0);
9508 scope = tsubst (scope, args, complain, in_decl);
9509 expr = tsubst_copy (name, args, complain, in_decl);
9514 if (dependent_type_p (scope))
9515 return build_qualified_name (/*type=*/NULL_TREE,
9517 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
9519 if (!BASELINK_P (name) && !DECL_P (expr))
9521 if (TREE_CODE (expr) == BIT_NOT_EXPR)
9522 /* If this were actually a destructor call, it would have been
9523 parsed as such by the parser. */
9524 expr = error_mark_node;
9526 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
9527 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
9528 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
9530 if (complain & tf_error)
9532 error ("dependent-name %qE is parsed as a non-type, but "
9533 "instantiation yields a type", qualified_id);
9534 inform ("say %<typename %E%> if a type is meant", qualified_id);
9536 return error_mark_node;
9542 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
9544 /* Remember that there was a reference to this entity. */
9548 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
9550 if (complain & tf_error)
9551 qualified_name_lookup_error (scope,
9552 TREE_OPERAND (qualified_id, 1),
9554 return error_mark_node;
9558 expr = lookup_template_function (expr, template_args);
9560 if (expr == error_mark_node && complain & tf_error)
9561 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
9563 else if (TYPE_P (scope))
9565 expr = (adjust_result_of_qualified_name_lookup
9566 (expr, scope, current_class_type));
9567 expr = (finish_qualified_id_expr
9568 (scope, expr, done, address_p,
9569 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
9570 /*template_arg_p=*/false));
9573 /* Expressions do not generally have reference type. */
9574 if (TREE_CODE (expr) != SCOPE_REF
9575 /* However, if we're about to form a pointer-to-member, we just
9576 want the referenced member referenced. */
9577 && TREE_CODE (expr) != OFFSET_REF)
9578 expr = convert_from_reference (expr);
9583 /* Like tsubst, but deals with expressions. This function just replaces
9584 template parms; to finish processing the resultant expression, use
9588 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9590 enum tree_code code;
9593 if (t == NULL_TREE || t == error_mark_node)
9596 code = TREE_CODE (t);
9601 r = retrieve_local_specialization (t);
9602 gcc_assert (r != NULL);
9603 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
9604 r = ARGUMENT_PACK_SELECT_ARG (r);
9613 if (DECL_TEMPLATE_PARM_P (t))
9614 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
9615 /* There is no need to substitute into namespace-scope
9617 if (DECL_NAMESPACE_SCOPE_P (t))
9619 /* If ARGS is NULL, then T is known to be non-dependent. */
9620 if (args == NULL_TREE)
9621 return integral_constant_value (t);
9623 /* Unfortunately, we cannot just call lookup_name here.
9626 template <int I> int f() {
9628 struct S { void g() { E e = a; } };
9631 When we instantiate f<7>::S::g(), say, lookup_name is not
9632 clever enough to find f<7>::a. */
9634 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
9635 /*entering_scope=*/0);
9637 for (v = TYPE_VALUES (enum_type);
9640 if (TREE_PURPOSE (v) == DECL_NAME (t))
9641 return TREE_VALUE (v);
9643 /* We didn't find the name. That should never happen; if
9644 name-lookup found it during preliminary parsing, we
9645 should find it again here during instantiation. */
9651 if (DECL_CONTEXT (t))
9655 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
9656 /*entering_scope=*/1);
9657 if (ctx != DECL_CONTEXT (t))
9659 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
9662 if (complain & tf_error)
9663 error ("using invalid field %qD", t);
9664 return error_mark_node;
9674 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
9675 || local_variable_p (t))
9676 t = tsubst (t, args, complain, in_decl);
9681 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
9684 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9685 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
9686 args, complain, in_decl);
9687 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
9688 return tsubst (t, args, complain, in_decl);
9689 else if (DECL_CLASS_SCOPE_P (t)
9690 && uses_template_parms (DECL_CONTEXT (t)))
9692 /* Template template argument like the following example need
9695 template <template <class> class TT> struct C {};
9696 template <class T> struct D {
9697 template <class U> struct E {};
9702 We are processing the template argument `E' in #1 for
9703 the template instantiation #2. Originally, `E' is a
9704 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
9705 have to substitute this with one having context `D<int>'. */
9707 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
9708 return lookup_field (context, DECL_NAME(t), 0, false);
9711 /* Ordinary template template argument. */
9715 case REINTERPRET_CAST_EXPR:
9716 case CONST_CAST_EXPR:
9717 case STATIC_CAST_EXPR:
9718 case DYNAMIC_CAST_EXPR:
9721 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
9722 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
9725 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
9727 /* We only want to compute the number of arguments. */
9728 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
9730 if (expanded == error_mark_node)
9731 return error_mark_node;
9732 return build_int_cst (size_type_node, TREE_VEC_LENGTH (expanded));
9738 case TRUTH_NOT_EXPR:
9741 case UNARY_PLUS_EXPR: /* Unary + */
9749 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
9750 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
9757 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
9758 name = TREE_OPERAND (t, 1);
9759 if (TREE_CODE (name) == BIT_NOT_EXPR)
9761 name = tsubst_copy (TREE_OPERAND (name, 0), args,
9763 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
9765 else if (TREE_CODE (name) == SCOPE_REF
9766 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
9768 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
9770 name = TREE_OPERAND (name, 1);
9771 name = tsubst_copy (TREE_OPERAND (name, 0), args,
9773 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
9774 name = build_qualified_name (/*type=*/NULL_TREE,
9776 /*template_p=*/false);
9778 else if (TREE_CODE (name) == BASELINK)
9779 name = tsubst_baselink (name,
9780 non_reference (TREE_TYPE (object)),
9784 name = tsubst_copy (name, args, complain, in_decl);
9785 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
9791 case TRUNC_DIV_EXPR:
9793 case FLOOR_DIV_EXPR:
9794 case ROUND_DIV_EXPR:
9795 case EXACT_DIV_EXPR:
9799 case TRUNC_MOD_EXPR:
9800 case FLOOR_MOD_EXPR:
9801 case TRUTH_ANDIF_EXPR:
9802 case TRUTH_ORIF_EXPR:
9803 case TRUTH_AND_EXPR:
9820 case PREDECREMENT_EXPR:
9821 case PREINCREMENT_EXPR:
9822 case POSTDECREMENT_EXPR:
9823 case POSTINCREMENT_EXPR:
9825 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
9826 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
9829 return build_qualified_name (/*type=*/NULL_TREE,
9830 tsubst_copy (TREE_OPERAND (t, 0),
9831 args, complain, in_decl),
9832 tsubst_copy (TREE_OPERAND (t, 1),
9833 args, complain, in_decl),
9834 QUALIFIED_NAME_IS_TEMPLATE (t));
9839 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
9840 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
9841 NULL_TREE, NULL_TREE);
9845 int n = VL_EXP_OPERAND_LENGTH (t);
9846 tree result = build_vl_exp (CALL_EXPR, n);
9848 for (i = 0; i < n; i++)
9849 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
9856 case PSEUDO_DTOR_EXPR:
9859 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
9860 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
9861 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
9862 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
9869 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
9870 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
9871 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
9872 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
9879 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
9880 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
9881 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
9882 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
9886 case TEMPLATE_ID_EXPR:
9888 /* Substituted template arguments */
9889 tree fn = TREE_OPERAND (t, 0);
9890 tree targs = TREE_OPERAND (t, 1);
9892 fn = tsubst_copy (fn, args, complain, in_decl);
9894 targs = tsubst_template_args (targs, args, complain, in_decl);
9896 return lookup_template_function (fn, targs);
9901 tree purpose, value, chain;
9903 if (t == void_list_node)
9906 purpose = TREE_PURPOSE (t);
9908 purpose = tsubst_copy (purpose, args, complain, in_decl);
9909 value = TREE_VALUE (t);
9911 value = tsubst_copy (value, args, complain, in_decl);
9912 chain = TREE_CHAIN (t);
9913 if (chain && chain != void_type_node)
9914 chain = tsubst_copy (chain, args, complain, in_decl);
9915 if (purpose == TREE_PURPOSE (t)
9916 && value == TREE_VALUE (t)
9917 && chain == TREE_CHAIN (t))
9919 return tree_cons (purpose, value, chain);
9926 case TEMPLATE_TYPE_PARM:
9927 case TEMPLATE_TEMPLATE_PARM:
9928 case BOUND_TEMPLATE_TEMPLATE_PARM:
9929 case TEMPLATE_PARM_INDEX:
9931 case REFERENCE_TYPE:
9937 case UNBOUND_CLASS_TEMPLATE:
9941 return tsubst (t, args, complain, in_decl);
9943 case IDENTIFIER_NODE:
9944 if (IDENTIFIER_TYPENAME_P (t))
9946 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9947 return mangle_conv_op_name_for_type (new_type);
9953 /* This is handled by tsubst_copy_and_build. */
9957 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
9959 tsubst (TREE_TYPE (t), args, complain, in_decl));
9961 case CLEANUP_POINT_EXPR:
9962 /* We shouldn't have built any of these during initial template
9963 generation. Instead, they should be built during instantiation
9964 in response to the saved STMT_IS_FULL_EXPR_P setting. */
9968 mark_used (TREE_OPERAND (t, 1));
9971 case EXPR_PACK_EXPANSION:
9972 error ("invalid use of pack expansion expression");
9973 return error_mark_node;
9975 case NONTYPE_ARGUMENT_PACK:
9976 error ("use %<...%> to expand argument pack");
9977 return error_mark_node;
9984 /* Like tsubst_copy, but specifically for OpenMP clauses. */
9987 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
9990 tree new_clauses = NULL, nc, oc;
9992 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
9994 nc = copy_node (oc);
9995 OMP_CLAUSE_CHAIN (nc) = new_clauses;
9998 switch (OMP_CLAUSE_CODE (nc))
10000 case OMP_CLAUSE_PRIVATE:
10001 case OMP_CLAUSE_SHARED:
10002 case OMP_CLAUSE_FIRSTPRIVATE:
10003 case OMP_CLAUSE_LASTPRIVATE:
10004 case OMP_CLAUSE_REDUCTION:
10005 case OMP_CLAUSE_COPYIN:
10006 case OMP_CLAUSE_COPYPRIVATE:
10007 case OMP_CLAUSE_IF:
10008 case OMP_CLAUSE_NUM_THREADS:
10009 case OMP_CLAUSE_SCHEDULE:
10010 OMP_CLAUSE_OPERAND (nc, 0)
10011 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
10012 in_decl, /*integral_constant_expression_p=*/false);
10014 case OMP_CLAUSE_NOWAIT:
10015 case OMP_CLAUSE_ORDERED:
10016 case OMP_CLAUSE_DEFAULT:
10019 gcc_unreachable ();
10023 return finish_omp_clauses (nreverse (new_clauses));
10026 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
10029 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
10032 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
10034 tree purpose, value, chain;
10039 if (TREE_CODE (t) != TREE_LIST)
10040 return tsubst_copy_and_build (t, args, complain, in_decl,
10041 /*function_p=*/false,
10042 /*integral_constant_expression_p=*/false);
10044 if (t == void_list_node)
10047 purpose = TREE_PURPOSE (t);
10049 purpose = RECUR (purpose);
10050 value = TREE_VALUE (t);
10052 value = RECUR (value);
10053 chain = TREE_CHAIN (t);
10054 if (chain && chain != void_type_node)
10055 chain = RECUR (chain);
10056 return tree_cons (purpose, value, chain);
10060 /* Like tsubst_copy for expressions, etc. but also does semantic
10064 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
10065 bool integral_constant_expression_p)
10067 #define RECUR(NODE) \
10068 tsubst_expr ((NODE), args, complain, in_decl, \
10069 integral_constant_expression_p)
10073 if (t == NULL_TREE || t == error_mark_node)
10076 if (EXPR_HAS_LOCATION (t))
10077 input_location = EXPR_LOCATION (t);
10078 if (STATEMENT_CODE_P (TREE_CODE (t)))
10079 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
10081 switch (TREE_CODE (t))
10083 case STATEMENT_LIST:
10085 tree_stmt_iterator i;
10086 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
10087 RECUR (tsi_stmt (i));
10091 case CTOR_INITIALIZER:
10092 finish_mem_initializers (tsubst_initializer_list
10093 (TREE_OPERAND (t, 0), args));
10097 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
10101 tmp = RECUR (EXPR_STMT_EXPR (t));
10102 if (EXPR_STMT_STMT_EXPR_RESULT (t))
10103 finish_stmt_expr_expr (tmp, cur_stmt_expr);
10105 finish_expr_stmt (tmp);
10109 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
10117 decl = DECL_EXPR_DECL (t);
10118 if (TREE_CODE (decl) == LABEL_DECL)
10119 finish_label_decl (DECL_NAME (decl));
10120 else if (TREE_CODE (decl) == USING_DECL)
10122 tree scope = USING_DECL_SCOPE (decl);
10123 tree name = DECL_NAME (decl);
10126 scope = RECUR (scope);
10127 decl = lookup_qualified_name (scope, name,
10128 /*is_type_p=*/false,
10129 /*complain=*/false);
10130 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
10131 qualified_name_lookup_error (scope, name, decl);
10133 do_local_using_decl (decl, scope, name);
10137 init = DECL_INITIAL (decl);
10138 decl = tsubst (decl, args, complain, in_decl);
10139 if (decl != error_mark_node)
10141 /* By marking the declaration as instantiated, we avoid
10142 trying to instantiate it. Since instantiate_decl can't
10143 handle local variables, and since we've already done
10144 all that needs to be done, that's the right thing to
10146 if (TREE_CODE (decl) == VAR_DECL)
10147 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
10148 if (TREE_CODE (decl) == VAR_DECL
10149 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
10150 /* Anonymous aggregates are a special case. */
10151 finish_anon_union (decl);
10154 maybe_push_decl (decl);
10155 if (TREE_CODE (decl) == VAR_DECL
10156 && DECL_PRETTY_FUNCTION_P (decl))
10158 /* For __PRETTY_FUNCTION__ we have to adjust the
10160 const char *const name
10161 = cxx_printable_name (current_function_decl, 2);
10162 init = cp_fname_init (name, &TREE_TYPE (decl));
10166 tree t = RECUR (init);
10169 /* If we had an initializer but it
10170 instantiated to nothing,
10171 value-initialize the object. This will
10172 only occur when the initializer was a
10173 pack expansion where the parameter packs
10174 used in that expansion were of length
10176 init = build_default_init (TREE_TYPE (decl),
10182 finish_decl (decl, init, NULL_TREE);
10187 /* A DECL_EXPR can also be used as an expression, in the condition
10188 clause of an if/for/while construct. */
10193 stmt = begin_for_stmt ();
10194 RECUR (FOR_INIT_STMT (t));
10195 finish_for_init_stmt (stmt);
10196 tmp = RECUR (FOR_COND (t));
10197 finish_for_cond (tmp, stmt);
10198 tmp = RECUR (FOR_EXPR (t));
10199 finish_for_expr (tmp, stmt);
10200 RECUR (FOR_BODY (t));
10201 finish_for_stmt (stmt);
10205 stmt = begin_while_stmt ();
10206 tmp = RECUR (WHILE_COND (t));
10207 finish_while_stmt_cond (tmp, stmt);
10208 RECUR (WHILE_BODY (t));
10209 finish_while_stmt (stmt);
10213 stmt = begin_do_stmt ();
10214 RECUR (DO_BODY (t));
10215 finish_do_body (stmt);
10216 tmp = RECUR (DO_COND (t));
10217 finish_do_stmt (tmp, stmt);
10221 stmt = begin_if_stmt ();
10222 tmp = RECUR (IF_COND (t));
10223 finish_if_stmt_cond (tmp, stmt);
10224 RECUR (THEN_CLAUSE (t));
10225 finish_then_clause (stmt);
10227 if (ELSE_CLAUSE (t))
10229 begin_else_clause (stmt);
10230 RECUR (ELSE_CLAUSE (t));
10231 finish_else_clause (stmt);
10234 finish_if_stmt (stmt);
10238 if (BIND_EXPR_BODY_BLOCK (t))
10239 stmt = begin_function_body ();
10241 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
10242 ? BCS_TRY_BLOCK : 0);
10244 RECUR (BIND_EXPR_BODY (t));
10246 if (BIND_EXPR_BODY_BLOCK (t))
10247 finish_function_body (stmt);
10249 finish_compound_stmt (stmt);
10253 finish_break_stmt ();
10256 case CONTINUE_STMT:
10257 finish_continue_stmt ();
10261 stmt = begin_switch_stmt ();
10262 tmp = RECUR (SWITCH_STMT_COND (t));
10263 finish_switch_cond (tmp, stmt);
10264 RECUR (SWITCH_STMT_BODY (t));
10265 finish_switch_stmt (stmt);
10268 case CASE_LABEL_EXPR:
10269 finish_case_label (RECUR (CASE_LOW (t)),
10270 RECUR (CASE_HIGH (t)));
10274 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
10278 tmp = GOTO_DESTINATION (t);
10279 if (TREE_CODE (tmp) != LABEL_DECL)
10280 /* Computed goto's must be tsubst'd into. On the other hand,
10281 non-computed gotos must not be; the identifier in question
10282 will have no binding. */
10285 tmp = DECL_NAME (tmp);
10286 finish_goto_stmt (tmp);
10290 tmp = finish_asm_stmt
10291 (ASM_VOLATILE_P (t),
10292 RECUR (ASM_STRING (t)),
10293 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
10294 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
10295 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl));
10297 tree asm_expr = tmp;
10298 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
10299 asm_expr = TREE_OPERAND (asm_expr, 0);
10300 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
10307 stmt = begin_try_block ();
10308 RECUR (TRY_STMTS (t));
10309 finish_cleanup_try_block (stmt);
10310 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
10314 tree compound_stmt = NULL_TREE;
10316 if (FN_TRY_BLOCK_P (t))
10317 stmt = begin_function_try_block (&compound_stmt);
10319 stmt = begin_try_block ();
10321 RECUR (TRY_STMTS (t));
10323 if (FN_TRY_BLOCK_P (t))
10324 finish_function_try_block (stmt);
10326 finish_try_block (stmt);
10328 RECUR (TRY_HANDLERS (t));
10329 if (FN_TRY_BLOCK_P (t))
10330 finish_function_handler_sequence (stmt, compound_stmt);
10332 finish_handler_sequence (stmt);
10338 tree decl = HANDLER_PARMS (t);
10342 decl = tsubst (decl, args, complain, in_decl);
10343 /* Prevent instantiate_decl from trying to instantiate
10344 this variable. We've already done all that needs to be
10346 if (decl != error_mark_node)
10347 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
10349 stmt = begin_handler ();
10350 finish_handler_parms (decl, stmt);
10351 RECUR (HANDLER_BODY (t));
10352 finish_handler (stmt);
10357 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
10360 case STATIC_ASSERT:
10363 tsubst_expr (STATIC_ASSERT_CONDITION (t),
10366 /*integral_constant_expression_p=*/true);
10367 finish_static_assert (condition,
10368 STATIC_ASSERT_MESSAGE (t),
10369 STATIC_ASSERT_SOURCE_LOCATION (t),
10370 /*member_p=*/false);
10375 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
10376 args, complain, in_decl);
10377 stmt = begin_omp_parallel ();
10378 RECUR (OMP_PARALLEL_BODY (t));
10379 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
10380 = OMP_PARALLEL_COMBINED (t);
10385 tree clauses, decl, init, cond, incr, body, pre_body;
10387 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
10388 args, complain, in_decl);
10389 init = OMP_FOR_INIT (t);
10390 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
10391 decl = RECUR (TREE_OPERAND (init, 0));
10392 init = RECUR (TREE_OPERAND (init, 1));
10393 cond = RECUR (OMP_FOR_COND (t));
10394 incr = RECUR (OMP_FOR_INCR (t));
10396 stmt = begin_omp_structured_block ();
10398 pre_body = push_stmt_list ();
10399 RECUR (OMP_FOR_PRE_BODY (t));
10400 pre_body = pop_stmt_list (pre_body);
10402 body = push_stmt_list ();
10403 RECUR (OMP_FOR_BODY (t));
10404 body = pop_stmt_list (body);
10406 t = finish_omp_for (EXPR_LOCATION (t), decl, init, cond, incr, body,
10409 OMP_FOR_CLAUSES (t) = clauses;
10411 add_stmt (finish_omp_structured_block (stmt));
10417 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
10418 stmt = push_stmt_list ();
10419 RECUR (OMP_BODY (t));
10420 stmt = pop_stmt_list (stmt);
10423 OMP_BODY (t) = stmt;
10424 OMP_CLAUSES (t) = tmp;
10432 stmt = push_stmt_list ();
10433 RECUR (OMP_BODY (t));
10434 stmt = pop_stmt_list (stmt);
10437 OMP_BODY (t) = stmt;
10442 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
10444 tree op1 = TREE_OPERAND (t, 1);
10445 tree lhs = RECUR (TREE_OPERAND (op1, 0));
10446 tree rhs = RECUR (TREE_OPERAND (op1, 1));
10447 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
10451 case EXPR_PACK_EXPANSION:
10452 error ("invalid use of pack expansion expression");
10453 return error_mark_node;
10455 case NONTYPE_ARGUMENT_PACK:
10456 error ("use %<...%> to expand argument pack");
10457 return error_mark_node;
10460 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
10462 return tsubst_copy_and_build (t, args, complain, in_decl,
10463 /*function_p=*/false,
10464 integral_constant_expression_p);
10471 /* T is a postfix-expression that is not being used in a function
10472 call. Return the substituted version of T. */
10475 tsubst_non_call_postfix_expression (tree t, tree args,
10476 tsubst_flags_t complain,
10479 if (TREE_CODE (t) == SCOPE_REF)
10480 t = tsubst_qualified_id (t, args, complain, in_decl,
10481 /*done=*/false, /*address_p=*/false);
10483 t = tsubst_copy_and_build (t, args, complain, in_decl,
10484 /*function_p=*/false,
10485 /*integral_constant_expression_p=*/false);
10490 /* Like tsubst but deals with expressions and performs semantic
10491 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
10494 tsubst_copy_and_build (tree t,
10496 tsubst_flags_t complain,
10499 bool integral_constant_expression_p)
10501 #define RECUR(NODE) \
10502 tsubst_copy_and_build (NODE, args, complain, in_decl, \
10503 /*function_p=*/false, \
10504 integral_constant_expression_p)
10508 if (t == NULL_TREE || t == error_mark_node)
10511 switch (TREE_CODE (t))
10515 /* Fall through. */
10516 case IDENTIFIER_NODE:
10520 bool non_integral_constant_expression_p;
10521 const char *error_msg;
10523 if (IDENTIFIER_TYPENAME_P (t))
10525 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10526 t = mangle_conv_op_name_for_type (new_type);
10529 /* Look up the name. */
10530 decl = lookup_name (t);
10532 /* By convention, expressions use ERROR_MARK_NODE to indicate
10533 failure, not NULL_TREE. */
10534 if (decl == NULL_TREE)
10535 decl = error_mark_node;
10537 decl = finish_id_expression (t, decl, NULL_TREE,
10539 integral_constant_expression_p,
10540 /*allow_non_integral_constant_expression_p=*/false,
10541 &non_integral_constant_expression_p,
10542 /*template_p=*/false,
10544 /*address_p=*/false,
10545 /*template_arg_p=*/false,
10549 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
10550 decl = unqualified_name_lookup_error (decl);
10554 case TEMPLATE_ID_EXPR:
10557 tree template = RECUR (TREE_OPERAND (t, 0));
10558 tree targs = TREE_OPERAND (t, 1);
10561 targs = tsubst_template_args (targs, args, complain, in_decl);
10563 if (TREE_CODE (template) == COMPONENT_REF)
10565 object = TREE_OPERAND (template, 0);
10566 template = TREE_OPERAND (template, 1);
10569 object = NULL_TREE;
10570 template = lookup_template_function (template, targs);
10573 return build3 (COMPONENT_REF, TREE_TYPE (template),
10574 object, template, NULL_TREE);
10576 return baselink_for_fns (template);
10581 tree r = RECUR (TREE_OPERAND (t, 0));
10583 if (REFERENCE_REF_P (t))
10585 /* A type conversion to reference type will be enclosed in
10586 such an indirect ref, but the substitution of the cast
10587 will have also added such an indirect ref. */
10588 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
10589 r = convert_from_reference (r);
10592 r = build_x_indirect_ref (r, "unary *");
10598 (tsubst (TREE_TYPE (t), args, complain, in_decl),
10599 RECUR (TREE_OPERAND (t, 0)));
10602 case REINTERPRET_CAST_EXPR:
10603 case CONST_CAST_EXPR:
10604 case DYNAMIC_CAST_EXPR:
10605 case STATIC_CAST_EXPR:
10610 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10611 if (integral_constant_expression_p
10612 && !cast_valid_in_integral_constant_expression_p (type))
10614 error ("a cast to a type other than an integral or "
10615 "enumeration type cannot appear in a constant-expression");
10616 return error_mark_node;
10619 op = RECUR (TREE_OPERAND (t, 0));
10621 switch (TREE_CODE (t))
10624 return build_functional_cast (type, op);
10625 case REINTERPRET_CAST_EXPR:
10626 return build_reinterpret_cast (type, op);
10627 case CONST_CAST_EXPR:
10628 return build_const_cast (type, op);
10629 case DYNAMIC_CAST_EXPR:
10630 return build_dynamic_cast (type, op);
10631 case STATIC_CAST_EXPR:
10632 return build_static_cast (type, op);
10634 gcc_unreachable ();
10638 case POSTDECREMENT_EXPR:
10639 case POSTINCREMENT_EXPR:
10640 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
10641 args, complain, in_decl);
10642 return build_x_unary_op (TREE_CODE (t), op1);
10644 case PREDECREMENT_EXPR:
10645 case PREINCREMENT_EXPR:
10649 case TRUTH_NOT_EXPR:
10650 case UNARY_PLUS_EXPR: /* Unary + */
10651 case REALPART_EXPR:
10652 case IMAGPART_EXPR:
10653 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
10656 op1 = TREE_OPERAND (t, 0);
10657 if (TREE_CODE (op1) == SCOPE_REF)
10658 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
10659 /*done=*/true, /*address_p=*/true);
10661 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
10663 if (TREE_CODE (op1) == LABEL_DECL)
10664 return finish_label_address_expr (DECL_NAME (op1));
10665 return build_x_unary_op (ADDR_EXPR, op1);
10670 case TRUNC_DIV_EXPR:
10671 case CEIL_DIV_EXPR:
10672 case FLOOR_DIV_EXPR:
10673 case ROUND_DIV_EXPR:
10674 case EXACT_DIV_EXPR:
10678 case TRUNC_MOD_EXPR:
10679 case FLOOR_MOD_EXPR:
10680 case TRUTH_ANDIF_EXPR:
10681 case TRUTH_ORIF_EXPR:
10682 case TRUTH_AND_EXPR:
10683 case TRUTH_OR_EXPR:
10698 return build_x_binary_op
10700 RECUR (TREE_OPERAND (t, 0)),
10701 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
10703 : TREE_CODE (TREE_OPERAND (t, 0))),
10704 RECUR (TREE_OPERAND (t, 1)),
10705 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
10707 : TREE_CODE (TREE_OPERAND (t, 1))),
10708 /*overloaded_p=*/NULL);
10711 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
10712 /*address_p=*/false);
10714 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
10715 args, complain, in_decl);
10716 return build_x_binary_op (ARRAY_REF, op1,
10717 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
10719 : TREE_CODE (TREE_OPERAND (t, 0))),
10720 RECUR (TREE_OPERAND (t, 1)),
10721 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
10723 : TREE_CODE (TREE_OPERAND (t, 1))),
10724 /*overloaded_p=*/NULL);
10727 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
10729 /* We only want to compute the number of arguments. */
10730 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
10731 complain, in_decl);
10732 if (expanded == error_mark_node)
10733 return error_mark_node;
10734 return build_int_cst (size_type_node, TREE_VEC_LENGTH (expanded));
10739 op1 = TREE_OPERAND (t, 0);
10742 /* When there are no ARGS, we are trying to evaluate a
10743 non-dependent expression from the parser. Trying to do
10744 the substitutions may not work. */
10746 op1 = TREE_TYPE (op1);
10751 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
10752 /*function_p=*/false,
10753 /*integral_constant_expression_p=*/false);
10757 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
10759 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
10763 tree r = build_x_modify_expr
10764 (RECUR (TREE_OPERAND (t, 0)),
10765 TREE_CODE (TREE_OPERAND (t, 1)),
10766 RECUR (TREE_OPERAND (t, 2)));
10767 /* TREE_NO_WARNING must be set if either the expression was
10768 parenthesized or it uses an operator such as >>= rather
10769 than plain assignment. In the former case, it was already
10770 set and must be copied. In the latter case,
10771 build_x_modify_expr sets it and it must not be reset
10773 if (TREE_NO_WARNING (t))
10774 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
10779 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
10780 args, complain, in_decl);
10781 /* Remember that there was a reference to this entity. */
10784 return build_x_arrow (op1);
10788 tree init = RECUR (TREE_OPERAND (t, 3));
10790 if (TREE_OPERAND (t, 3) && !init)
10791 /* If there was an initializer in the the original tree, but
10792 it instantiated to an empty list, then we should pass on
10793 VOID_ZERO_NODE to tell build_new that it was an empty
10794 initializer () rather than no initializer. This can only
10795 happen when the initializer is a pack expansion whose
10796 parameter packs are of length zero. */
10797 init = void_zero_node;
10800 (RECUR (TREE_OPERAND (t, 0)),
10801 RECUR (TREE_OPERAND (t, 1)),
10802 RECUR (TREE_OPERAND (t, 2)),
10804 NEW_EXPR_USE_GLOBAL (t));
10808 return delete_sanity
10809 (RECUR (TREE_OPERAND (t, 0)),
10810 RECUR (TREE_OPERAND (t, 1)),
10811 DELETE_EXPR_USE_VEC (t),
10812 DELETE_EXPR_USE_GLOBAL (t));
10814 case COMPOUND_EXPR:
10815 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
10816 RECUR (TREE_OPERAND (t, 1)));
10825 function = CALL_EXPR_FN (t);
10826 /* When we parsed the expression, we determined whether or
10827 not Koenig lookup should be performed. */
10828 koenig_p = KOENIG_LOOKUP_P (t);
10829 if (TREE_CODE (function) == SCOPE_REF)
10831 qualified_p = true;
10832 function = tsubst_qualified_id (function, args, complain, in_decl,
10834 /*address_p=*/false);
10838 if (TREE_CODE (function) == COMPONENT_REF)
10840 tree op = TREE_OPERAND (function, 1);
10842 qualified_p = (TREE_CODE (op) == SCOPE_REF
10843 || (BASELINK_P (op)
10844 && BASELINK_QUALIFIED_P (op)));
10847 qualified_p = false;
10849 function = tsubst_copy_and_build (function, args, complain,
10852 integral_constant_expression_p);
10854 if (BASELINK_P (function))
10855 qualified_p = true;
10858 /* FIXME: Rewrite this so as not to construct an arglist. */
10859 call_args = RECUR (CALL_EXPR_ARGS (t));
10861 /* We do not perform argument-dependent lookup if normal
10862 lookup finds a non-function, in accordance with the
10863 expected resolution of DR 218. */
10865 && ((is_overloaded_fn (function)
10866 /* If lookup found a member function, the Koenig lookup is
10867 not appropriate, even if an unqualified-name was used
10868 to denote the function. */
10869 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
10870 || TREE_CODE (function) == IDENTIFIER_NODE))
10871 function = perform_koenig_lookup (function, call_args);
10873 if (TREE_CODE (function) == IDENTIFIER_NODE)
10875 unqualified_name_lookup_error (function);
10876 return error_mark_node;
10879 /* Remember that there was a reference to this entity. */
10880 if (DECL_P (function))
10881 mark_used (function);
10883 if (TREE_CODE (function) == OFFSET_REF)
10884 return build_offset_ref_call_from_tree (function, call_args);
10885 if (TREE_CODE (function) == COMPONENT_REF)
10887 if (!BASELINK_P (TREE_OPERAND (function, 1)))
10888 return finish_call_expr (function, call_args,
10889 /*disallow_virtual=*/false,
10890 /*koenig_p=*/false);
10892 return (build_new_method_call
10893 (TREE_OPERAND (function, 0),
10894 TREE_OPERAND (function, 1),
10895 call_args, NULL_TREE,
10896 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
10899 return finish_call_expr (function, call_args,
10900 /*disallow_virtual=*/qualified_p,
10905 return build_x_conditional_expr
10906 (RECUR (TREE_OPERAND (t, 0)),
10907 RECUR (TREE_OPERAND (t, 1)),
10908 RECUR (TREE_OPERAND (t, 2)));
10910 case PSEUDO_DTOR_EXPR:
10911 return finish_pseudo_destructor_expr
10912 (RECUR (TREE_OPERAND (t, 0)),
10913 RECUR (TREE_OPERAND (t, 1)),
10914 RECUR (TREE_OPERAND (t, 2)));
10918 tree purpose, value, chain;
10920 if (t == void_list_node)
10923 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
10924 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
10926 /* We have pack expansions, so expand those and
10927 create a new list out of it. */
10928 tree purposevec = NULL_TREE;
10929 tree valuevec = NULL_TREE;
10933 /* Expand the argument expressions. */
10934 if (TREE_PURPOSE (t))
10935 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
10936 complain, in_decl);
10937 if (TREE_VALUE (t))
10938 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
10939 complain, in_decl);
10941 /* Build the rest of the list. */
10942 chain = TREE_CHAIN (t);
10943 if (chain && chain != void_type_node)
10944 chain = RECUR (chain);
10946 /* Determine the number of arguments. */
10947 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
10949 len = TREE_VEC_LENGTH (purposevec);
10950 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
10952 else if (TREE_CODE (valuevec) == TREE_VEC)
10953 len = TREE_VEC_LENGTH (valuevec);
10956 /* Since we only performed a partial substitution into
10957 the argument pack, we only return a single list
10959 if (purposevec == TREE_PURPOSE (t)
10960 && valuevec == TREE_VALUE (t)
10961 && chain == TREE_CHAIN (t))
10964 return tree_cons (purposevec, valuevec, chain);
10967 /* Convert the argument vectors into a TREE_LIST */
10971 /* Grab the Ith values. */
10973 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
10976 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
10979 /* Build the list (backwards). */
10980 chain = tree_cons (purpose, value, chain);
10986 purpose = TREE_PURPOSE (t);
10988 purpose = RECUR (purpose);
10989 value = TREE_VALUE (t);
10991 value = RECUR (value);
10992 chain = TREE_CHAIN (t);
10993 if (chain && chain != void_type_node)
10994 chain = RECUR (chain);
10995 if (purpose == TREE_PURPOSE (t)
10996 && value == TREE_VALUE (t)
10997 && chain == TREE_CHAIN (t))
10999 return tree_cons (purpose, value, chain);
11002 case COMPONENT_REF:
11008 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11009 args, complain, in_decl);
11010 /* Remember that there was a reference to this entity. */
11011 if (DECL_P (object))
11012 mark_used (object);
11013 object_type = TREE_TYPE (object);
11015 member = TREE_OPERAND (t, 1);
11016 if (BASELINK_P (member))
11017 member = tsubst_baselink (member,
11018 non_reference (TREE_TYPE (object)),
11019 args, complain, in_decl);
11021 member = tsubst_copy (member, args, complain, in_decl);
11022 if (member == error_mark_node)
11023 return error_mark_node;
11025 if (object_type && !CLASS_TYPE_P (object_type))
11027 if (SCALAR_TYPE_P (object_type))
11029 tree s = NULL_TREE;
11030 tree dtor = member;
11032 if (TREE_CODE (dtor) == SCOPE_REF)
11034 s = TREE_OPERAND (dtor, 0);
11035 dtor = TREE_OPERAND (dtor, 1);
11037 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
11039 dtor = TREE_OPERAND (dtor, 0);
11041 return finish_pseudo_destructor_expr (object, s, dtor);
11045 else if (TREE_CODE (member) == SCOPE_REF
11046 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
11051 /* Lookup the template functions now that we know what the
11053 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
11054 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
11055 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
11056 /*is_type_p=*/false,
11057 /*complain=*/false);
11058 if (BASELINK_P (member))
11060 BASELINK_FUNCTIONS (member)
11061 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
11063 member = (adjust_result_of_qualified_name_lookup
11064 (member, BINFO_TYPE (BASELINK_BINFO (member)),
11069 qualified_name_lookup_error (object_type, tmpl, member);
11070 return error_mark_node;
11073 else if (TREE_CODE (member) == SCOPE_REF
11074 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
11075 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
11077 if (complain & tf_error)
11079 if (TYPE_P (TREE_OPERAND (member, 0)))
11080 error ("%qT is not a class or namespace",
11081 TREE_OPERAND (member, 0));
11083 error ("%qD is not a class or namespace",
11084 TREE_OPERAND (member, 0));
11086 return error_mark_node;
11088 else if (TREE_CODE (member) == FIELD_DECL)
11089 return finish_non_static_data_member (member, object, NULL_TREE);
11091 return finish_class_member_access_expr (object, member,
11092 /*template_p=*/false);
11097 (RECUR (TREE_OPERAND (t, 0)));
11101 VEC(constructor_elt,gc) *n;
11102 constructor_elt *ce;
11103 unsigned HOST_WIDE_INT idx;
11104 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11105 bool process_index_p;
11107 bool need_copy_p = false;
11109 if (type == error_mark_node)
11110 return error_mark_node;
11112 /* digest_init will do the wrong thing if we let it. */
11113 if (type && TYPE_PTRMEMFUNC_P (type))
11116 /* We do not want to process the index of aggregate
11117 initializers as they are identifier nodes which will be
11118 looked up by digest_init. */
11119 process_index_p = !(type && IS_AGGR_TYPE (type));
11121 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
11122 newlen = VEC_length (constructor_elt, n);
11123 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
11125 if (ce->index && process_index_p)
11126 ce->index = RECUR (ce->index);
11128 if (PACK_EXPANSION_P (ce->value))
11130 /* Substitute into the pack expansion. */
11131 ce->value = tsubst_pack_expansion (ce->value, args, complain,
11134 if (ce->value == error_mark_node)
11136 else if (TREE_VEC_LENGTH (ce->value) == 1)
11137 /* Just move the argument into place. */
11138 ce->value = TREE_VEC_ELT (ce->value, 0);
11141 /* Update the length of the final CONSTRUCTOR
11142 arguments vector, and note that we will need to
11144 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
11145 need_copy_p = true;
11149 ce->value = RECUR (ce->value);
11154 VEC(constructor_elt,gc) *old_n = n;
11156 n = VEC_alloc (constructor_elt, gc, newlen);
11157 for (idx = 0; VEC_iterate (constructor_elt, old_n, idx, ce);
11160 if (TREE_CODE (ce->value) == TREE_VEC)
11162 int i, len = TREE_VEC_LENGTH (ce->value);
11163 for (i = 0; i < len; ++i)
11164 CONSTRUCTOR_APPEND_ELT (n, 0,
11165 TREE_VEC_ELT (ce->value, i));
11168 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
11172 if (TREE_HAS_CONSTRUCTOR (t))
11173 return finish_compound_literal (type, n);
11175 return build_constructor (NULL_TREE, n);
11180 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
11181 if (TYPE_P (operand_0))
11182 return get_typeid (operand_0);
11183 return build_typeid (operand_0);
11193 tree r = tsubst_copy (t, args, complain, in_decl);
11195 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
11196 /* If the original type was a reference, we'll be wrapped in
11197 the appropriate INDIRECT_REF. */
11198 r = convert_from_reference (r);
11203 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
11204 tsubst_copy (TREE_TYPE (t), args, complain,
11207 case OFFSETOF_EXPR:
11208 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
11212 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
11213 complain, in_decl);
11215 tree type2 = TRAIT_EXPR_TYPE2 (t);
11217 type2 = tsubst_copy (type2, args, complain, in_decl);
11219 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
11224 tree old_stmt_expr = cur_stmt_expr;
11225 tree stmt_expr = begin_stmt_expr ();
11227 cur_stmt_expr = stmt_expr;
11228 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
11229 integral_constant_expression_p);
11230 stmt_expr = finish_stmt_expr (stmt_expr, false);
11231 cur_stmt_expr = old_stmt_expr;
11237 t = tsubst_copy (t, args, complain, in_decl);
11238 /* As in finish_id_expression, we resolve enumeration constants
11239 to their underlying values. */
11240 if (TREE_CODE (t) == CONST_DECL)
11242 used_types_insert (TREE_TYPE (t));
11243 return DECL_INITIAL (t);
11248 /* Handle Objective-C++ constructs, if appropriate. */
11251 = objcp_tsubst_copy_and_build (t, args, complain,
11252 in_decl, /*function_p=*/false);
11256 return tsubst_copy (t, args, complain, in_decl);
11262 /* Verify that the instantiated ARGS are valid. For type arguments,
11263 make sure that the type's linkage is ok. For non-type arguments,
11264 make sure they are constants if they are integral or enumerations.
11265 Emit an error under control of COMPLAIN, and return TRUE on error. */
11268 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
11270 int ix, len = DECL_NTPARMS (tmpl);
11271 bool result = false;
11273 for (ix = 0; ix != len; ix++)
11275 tree t = TREE_VEC_ELT (args, ix);
11279 /* [basic.link]: A name with no linkage (notably, the name
11280 of a class or enumeration declared in a local scope)
11281 shall not be used to declare an entity with linkage.
11282 This implies that names with no linkage cannot be used as
11283 template arguments. */
11284 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
11288 /* DR 488 makes use of a type with no linkage cause
11289 type deduction to fail. */
11290 if (complain & tf_error)
11292 if (TYPE_ANONYMOUS_P (nt))
11293 error ("%qT is/uses anonymous type", t);
11295 error ("template argument for %qD uses local type %qT",
11300 /* In order to avoid all sorts of complications, we do not
11301 allow variably-modified types as template arguments. */
11302 else if (variably_modified_type_p (t, NULL_TREE))
11304 if (complain & tf_error)
11305 error ("%qT is a variably modified type", t);
11309 /* A non-type argument of integral or enumerated type must be a
11311 else if (TREE_TYPE (t)
11312 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
11313 && !TREE_CONSTANT (t))
11315 if (complain & tf_error)
11316 error ("integral expression %qE is not constant", t);
11320 if (result && (complain & tf_error))
11321 error (" trying to instantiate %qD", tmpl);
11325 /* Instantiate the indicated variable or function template TMPL with
11326 the template arguments in TARG_PTR. */
11329 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
11334 HOST_WIDE_INT saved_processing_template_decl;
11336 if (tmpl == error_mark_node)
11337 return error_mark_node;
11339 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
11341 /* If this function is a clone, handle it specially. */
11342 if (DECL_CLONED_FUNCTION_P (tmpl))
11347 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
11349 if (spec == error_mark_node)
11350 return error_mark_node;
11352 /* Look for the clone. */
11353 FOR_EACH_CLONE (clone, spec)
11354 if (DECL_NAME (clone) == DECL_NAME (tmpl))
11356 /* We should always have found the clone by now. */
11357 gcc_unreachable ();
11361 /* Check to see if we already have this specialization. */
11362 spec = retrieve_specialization (tmpl, targ_ptr,
11363 /*class_specializations_p=*/false);
11364 if (spec != NULL_TREE)
11367 gen_tmpl = most_general_template (tmpl);
11368 if (tmpl != gen_tmpl)
11370 /* The TMPL is a partial instantiation. To get a full set of
11371 arguments we must add the arguments used to perform the
11372 partial instantiation. */
11373 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
11376 /* Check to see if we already have this specialization. */
11377 spec = retrieve_specialization (gen_tmpl, targ_ptr,
11378 /*class_specializations_p=*/false);
11379 if (spec != NULL_TREE)
11383 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
11385 return error_mark_node;
11387 /* We are building a FUNCTION_DECL, during which the access of its
11388 parameters and return types have to be checked. However this
11389 FUNCTION_DECL which is the desired context for access checking
11390 is not built yet. We solve this chicken-and-egg problem by
11391 deferring all checks until we have the FUNCTION_DECL. */
11392 push_deferring_access_checks (dk_deferred);
11394 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
11395 (because, for example, we have encountered a non-dependent
11396 function call in the body of a template function and must now
11397 determine which of several overloaded functions will be called),
11398 within the instantiation itself we are not processing a
11400 saved_processing_template_decl = processing_template_decl;
11401 processing_template_decl = 0;
11402 /* Substitute template parameters to obtain the specialization. */
11403 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
11404 targ_ptr, complain, gen_tmpl);
11405 processing_template_decl = saved_processing_template_decl;
11406 if (fndecl == error_mark_node)
11407 return error_mark_node;
11409 /* Now we know the specialization, compute access previously
11411 push_access_scope (fndecl);
11412 perform_deferred_access_checks ();
11413 pop_access_scope (fndecl);
11414 pop_deferring_access_checks ();
11416 /* The DECL_TI_TEMPLATE should always be the immediate parent
11417 template, not the most general template. */
11418 DECL_TI_TEMPLATE (fndecl) = tmpl;
11420 /* If we've just instantiated the main entry point for a function,
11421 instantiate all the alternate entry points as well. We do this
11422 by cloning the instantiation of the main entry point, not by
11423 instantiating the template clones. */
11424 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
11425 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
11430 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
11431 arguments that are being used when calling it. TARGS is a vector
11432 into which the deduced template arguments are placed.
11434 Return zero for success, 2 for an incomplete match that doesn't resolve
11435 all the types, and 1 for complete failure. An error message will be
11436 printed only for an incomplete match.
11438 If FN is a conversion operator, or we are trying to produce a specific
11439 specialization, RETURN_TYPE is the return type desired.
11441 The EXPLICIT_TARGS are explicit template arguments provided via a
11444 The parameter STRICT is one of:
11447 We are deducing arguments for a function call, as in
11448 [temp.deduct.call].
11451 We are deducing arguments for a conversion function, as in
11452 [temp.deduct.conv].
11455 We are deducing arguments when doing an explicit instantiation
11456 as in [temp.explicit], when determining an explicit specialization
11457 as in [temp.expl.spec], or when taking the address of a function
11458 template, as in [temp.deduct.funcaddr]. */
11461 fn_type_unification (tree fn,
11462 tree explicit_targs,
11466 unification_kind_t strict,
11472 bool incomplete_argument_packs_p = false;
11474 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
11476 fntype = TREE_TYPE (fn);
11477 if (explicit_targs)
11481 The specified template arguments must match the template
11482 parameters in kind (i.e., type, nontype, template), and there
11483 must not be more arguments than there are parameters;
11484 otherwise type deduction fails.
11486 Nontype arguments must match the types of the corresponding
11487 nontype template parameters, or must be convertible to the
11488 types of the corresponding nontype parameters as specified in
11489 _temp.arg.nontype_, otherwise type deduction fails.
11491 All references in the function type of the function template
11492 to the corresponding template parameters are replaced by the
11493 specified template argument values. If a substitution in a
11494 template parameter or in the function type of the function
11495 template results in an invalid type, type deduction fails. */
11496 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
11497 int i, len = TREE_VEC_LENGTH (tparms);
11498 tree converted_args;
11499 bool incomplete = false;
11501 if (explicit_targs == error_mark_node)
11505 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
11506 /*require_all_args=*/false,
11507 /*use_default_args=*/false));
11508 if (converted_args == error_mark_node)
11511 /* Substitute the explicit args into the function type. This is
11512 necessary so that, for instance, explicitly declared function
11513 arguments can match null pointed constants. If we were given
11514 an incomplete set of explicit args, we must not do semantic
11515 processing during substitution as we could create partial
11517 for (i = 0; i < len; i++)
11519 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
11520 bool parameter_pack = false;
11522 /* Dig out the actual parm. */
11523 if (TREE_CODE (parm) == TYPE_DECL
11524 || TREE_CODE (parm) == TEMPLATE_DECL)
11526 parm = TREE_TYPE (parm);
11527 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
11529 else if (TREE_CODE (parm) == PARM_DECL)
11531 parm = DECL_INITIAL (parm);
11532 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
11535 if (parameter_pack)
11539 template_parm_level_and_index (parm, &level, &idx);
11541 /* Mark the argument pack as "incomplete". We could
11542 still deduce more arguments during unification. */
11543 targ = TMPL_ARG (converted_args, level, idx);
11546 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
11547 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
11548 = ARGUMENT_PACK_ARGS (targ);
11551 /* We have some incomplete argument packs. */
11552 incomplete_argument_packs_p = true;
11556 if (incomplete_argument_packs_p)
11557 /* Any substitution is guaranteed to be incomplete if there
11558 are incomplete argument packs, because we can still deduce
11562 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
11564 processing_template_decl += incomplete;
11565 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
11566 processing_template_decl -= incomplete;
11568 if (fntype == error_mark_node)
11571 /* Place the explicitly specified arguments in TARGS. */
11572 for (i = NUM_TMPL_ARGS (converted_args); i--;)
11573 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
11576 /* Never do unification on the 'this' parameter. */
11577 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
11581 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
11582 args = tree_cons (NULL_TREE, return_type, args);
11585 /* We allow incomplete unification without an error message here
11586 because the standard doesn't seem to explicitly prohibit it. Our
11587 callers must be ready to deal with unification failures in any
11589 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
11590 targs, parms, args, /*subr=*/0,
11593 if (result == 0 && incomplete_argument_packs_p)
11595 int i, len = NUM_TMPL_ARGS (targs);
11597 /* Clear the "incomplete" flags on all argument packs. */
11598 for (i = 0; i < len; i++)
11600 tree arg = TREE_VEC_ELT (targs, i);
11601 if (ARGUMENT_PACK_P (arg))
11603 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
11604 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
11610 /* All is well so far. Now, check:
11614 When all template arguments have been deduced, all uses of
11615 template parameters in nondeduced contexts are replaced with
11616 the corresponding deduced argument values. If the
11617 substitution results in an invalid type, as described above,
11618 type deduction fails. */
11619 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
11620 == error_mark_node)
11626 /* Adjust types before performing type deduction, as described in
11627 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
11628 sections are symmetric. PARM is the type of a function parameter
11629 or the return type of the conversion function. ARG is the type of
11630 the argument passed to the call, or the type of the value
11631 initialized with the result of the conversion function.
11632 ARG_EXPR is the original argument expression, which may be null. */
11635 maybe_adjust_types_for_deduction (unification_kind_t strict,
11649 /* Swap PARM and ARG throughout the remainder of this
11650 function; the handling is precisely symmetric since PARM
11651 will initialize ARG rather than vice versa. */
11659 /* There is nothing to do in this case. */
11663 gcc_unreachable ();
11666 if (TREE_CODE (*parm) != REFERENCE_TYPE)
11668 /* [temp.deduct.call]
11670 If P is not a reference type:
11672 --If A is an array type, the pointer type produced by the
11673 array-to-pointer standard conversion (_conv.array_) is
11674 used in place of A for type deduction; otherwise,
11676 --If A is a function type, the pointer type produced by
11677 the function-to-pointer standard conversion
11678 (_conv.func_) is used in place of A for type deduction;
11681 --If A is a cv-qualified type, the top level
11682 cv-qualifiers of A's type are ignored for type
11684 if (TREE_CODE (*arg) == ARRAY_TYPE)
11685 *arg = build_pointer_type (TREE_TYPE (*arg));
11686 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
11687 *arg = build_pointer_type (*arg);
11689 *arg = TYPE_MAIN_VARIANT (*arg);
11692 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
11693 of the form T&&, where T is a template parameter, and the argument
11694 is an lvalue, T is deduced as A& */
11695 if (TREE_CODE (*parm) == REFERENCE_TYPE
11696 && TYPE_REF_IS_RVALUE (*parm)
11697 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
11698 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
11699 && arg_expr && real_lvalue_p (arg_expr))
11700 *arg = build_reference_type (*arg);
11702 /* [temp.deduct.call]
11704 If P is a cv-qualified type, the top level cv-qualifiers
11705 of P's type are ignored for type deduction. If P is a
11706 reference type, the type referred to by P is used for
11708 *parm = TYPE_MAIN_VARIANT (*parm);
11709 if (TREE_CODE (*parm) == REFERENCE_TYPE)
11711 *parm = TREE_TYPE (*parm);
11712 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
11715 /* DR 322. For conversion deduction, remove a reference type on parm
11716 too (which has been swapped into ARG). */
11717 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
11718 *arg = TREE_TYPE (*arg);
11723 /* Most parms like fn_type_unification.
11725 If SUBR is 1, we're being called recursively (to unify the
11726 arguments of a function or method parameter of a function
11730 type_unification_real (tree tparms,
11735 unification_kind_t strict,
11738 tree parm, arg, arg_expr;
11740 int ntparms = TREE_VEC_LENGTH (tparms);
11742 int saw_undeduced = 0;
11745 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
11746 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
11747 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
11748 gcc_assert (ntparms > 0);
11753 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
11754 | UNIFY_ALLOW_DERIVED);
11758 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
11762 sub_strict = UNIFY_ALLOW_NONE;
11766 gcc_unreachable ();
11773 while (parms && parms != void_list_node
11774 && args && args != void_list_node)
11776 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
11779 parm = TREE_VALUE (parms);
11780 parms = TREE_CHAIN (parms);
11781 arg = TREE_VALUE (args);
11782 args = TREE_CHAIN (args);
11785 if (arg == error_mark_node)
11787 if (arg == unknown_type_node)
11788 /* We can't deduce anything from this, but we might get all the
11789 template args from other function args. */
11792 /* Conversions will be performed on a function argument that
11793 corresponds with a function parameter that contains only
11794 non-deducible template parameters and explicitly specified
11795 template parameters. */
11796 if (!uses_template_parms (parm))
11801 type = TREE_TYPE (arg);
11805 if (same_type_p (parm, type))
11807 if (strict != DEDUCE_EXACT
11808 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
11817 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
11818 if (type_unknown_p (arg))
11820 /* [temp.deduct.type]
11822 A template-argument can be deduced from a pointer to
11823 function or pointer to member function argument if
11824 the set of overloaded functions does not contain
11825 function templates and at most one of a set of
11826 overloaded functions provides a unique match. */
11827 if (resolve_overloaded_unification
11828 (tparms, targs, parm, arg, strict, sub_strict))
11834 arg = unlowered_expr_type (arg);
11835 if (arg == error_mark_node)
11840 int arg_strict = sub_strict;
11843 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
11846 if (unify (tparms, targs, parm, arg, arg_strict))
11853 && parms != void_list_node
11854 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
11856 /* Unify the remaining arguments with the pack expansion type. */
11858 tree parmvec = make_tree_vec (1);
11862 /* Count the number of arguments that remain. */
11863 for (t = args; t && t != void_list_node; t = TREE_CHAIN (t))
11866 /* Allocate a TREE_VEC and copy in all of the arguments */
11867 argvec = make_tree_vec (len);
11868 for (i = 0; args && args != void_list_node; args = TREE_CHAIN (args))
11870 TREE_VEC_ELT (argvec, i) = TREE_VALUE (args);
11874 /* Copy the parameter into parmvec. */
11875 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
11876 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
11877 /*call_args_p=*/true, /*subr=*/subr))
11880 /* Advance to the end of the list of parameters. */
11881 parms = TREE_CHAIN (parms);
11884 /* Fail if we've reached the end of the parm list, and more args
11885 are present, and the parm list isn't variadic. */
11886 if (args && args != void_list_node && parms == void_list_node)
11888 /* Fail if parms are left and they don't have default values. */
11889 if (parms && parms != void_list_node
11890 && TREE_PURPOSE (parms) == NULL_TREE)
11894 for (i = 0; i < ntparms; i++)
11895 if (!TREE_VEC_ELT (targs, i))
11899 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
11902 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
11904 /* If this is an undeduced nontype parameter that depends on
11905 a type parameter, try another pass; its type may have been
11906 deduced from a later argument than the one from which
11907 this parameter can be deduced. */
11908 if (TREE_CODE (tparm) == PARM_DECL
11909 && uses_template_parms (TREE_TYPE (tparm))
11910 && !saw_undeduced++)
11913 /* Core issue #226 (C++0x) [temp.deduct]:
11915 If a template argument has not been deduced, its
11916 default template argument, if any, is used.
11918 When we are in C++98 mode, TREE_PURPOSE will either
11919 be NULL_TREE or ERROR_MARK_NODE, so we do not need
11920 to explicitly check cxx_dialect here. */
11921 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
11923 tree arg = tsubst (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)),
11924 targs, tf_none, NULL_TREE);
11925 if (arg == error_mark_node)
11929 TREE_VEC_ELT (targs, i) = arg;
11934 /* If the type parameter is a parameter pack, then it will
11935 be deduced to an empty parameter pack. */
11936 if (template_parameter_pack_p (tparm))
11940 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
11942 arg = make_node (NONTYPE_ARGUMENT_PACK);
11943 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
11944 TREE_CONSTANT (arg) = 1;
11947 arg = make_node (TYPE_ARGUMENT_PACK);
11949 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
11951 TREE_VEC_ELT (targs, i) = arg;
11961 /* Subroutine of type_unification_real. Args are like the variables
11962 at the call site. ARG is an overloaded function (or template-id);
11963 we try deducing template args from each of the overloads, and if
11964 only one succeeds, we go with that. Modifies TARGS and returns
11965 true on success. */
11968 resolve_overloaded_unification (tree tparms,
11972 unification_kind_t strict,
11975 tree tempargs = copy_node (targs);
11979 if (TREE_CODE (arg) == ADDR_EXPR)
11981 arg = TREE_OPERAND (arg, 0);
11987 if (TREE_CODE (arg) == COMPONENT_REF)
11988 /* Handle `&x' where `x' is some static or non-static member
11990 arg = TREE_OPERAND (arg, 1);
11992 if (TREE_CODE (arg) == OFFSET_REF)
11993 arg = TREE_OPERAND (arg, 1);
11995 /* Strip baselink information. */
11996 if (BASELINK_P (arg))
11997 arg = BASELINK_FUNCTIONS (arg);
11999 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
12001 /* If we got some explicit template args, we need to plug them into
12002 the affected templates before we try to unify, in case the
12003 explicit args will completely resolve the templates in question. */
12005 tree expl_subargs = TREE_OPERAND (arg, 1);
12006 arg = TREE_OPERAND (arg, 0);
12008 for (; arg; arg = OVL_NEXT (arg))
12010 tree fn = OVL_CURRENT (arg);
12011 tree subargs, elem;
12013 if (TREE_CODE (fn) != TEMPLATE_DECL)
12016 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
12017 expl_subargs, /*check_ret=*/false);
12020 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
12021 good += try_one_overload (tparms, targs, tempargs, parm,
12022 elem, strict, sub_strict, addr_p);
12026 else if (TREE_CODE (arg) != OVERLOAD
12027 && TREE_CODE (arg) != FUNCTION_DECL)
12028 /* If ARG is, for example, "(0, &f)" then its type will be unknown
12029 -- but the deduction does not succeed because the expression is
12030 not just the function on its own. */
12033 for (; arg; arg = OVL_NEXT (arg))
12034 good += try_one_overload (tparms, targs, tempargs, parm,
12035 TREE_TYPE (OVL_CURRENT (arg)),
12036 strict, sub_strict, addr_p);
12038 /* [temp.deduct.type] A template-argument can be deduced from a pointer
12039 to function or pointer to member function argument if the set of
12040 overloaded functions does not contain function templates and at most
12041 one of a set of overloaded functions provides a unique match.
12043 So if we found multiple possibilities, we return success but don't
12044 deduce anything. */
12048 int i = TREE_VEC_LENGTH (targs);
12050 if (TREE_VEC_ELT (tempargs, i))
12051 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
12059 /* Subroutine of resolve_overloaded_unification; does deduction for a single
12060 overload. Fills TARGS with any deduced arguments, or error_mark_node if
12061 different overloads deduce different arguments for a given parm.
12062 ADDR_P is true if the expression for which deduction is being
12063 performed was of the form "& fn" rather than simply "fn".
12065 Returns 1 on success. */
12068 try_one_overload (tree tparms,
12073 unification_kind_t strict,
12081 /* [temp.deduct.type] A template-argument can be deduced from a pointer
12082 to function or pointer to member function argument if the set of
12083 overloaded functions does not contain function templates and at most
12084 one of a set of overloaded functions provides a unique match.
12086 So if this is a template, just return success. */
12088 if (uses_template_parms (arg))
12091 if (TREE_CODE (arg) == METHOD_TYPE)
12092 arg = build_ptrmemfunc_type (build_pointer_type (arg));
12094 arg = build_pointer_type (arg);
12096 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
12098 /* We don't copy orig_targs for this because if we have already deduced
12099 some template args from previous args, unify would complain when we
12100 try to deduce a template parameter for the same argument, even though
12101 there isn't really a conflict. */
12102 nargs = TREE_VEC_LENGTH (targs);
12103 tempargs = make_tree_vec (nargs);
12105 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
12108 /* First make sure we didn't deduce anything that conflicts with
12109 explicitly specified args. */
12110 for (i = nargs; i--; )
12112 tree elt = TREE_VEC_ELT (tempargs, i);
12113 tree oldelt = TREE_VEC_ELT (orig_targs, i);
12117 else if (uses_template_parms (elt))
12118 /* Since we're unifying against ourselves, we will fill in
12119 template args used in the function parm list with our own
12120 template parms. Discard them. */
12121 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
12122 else if (oldelt && !template_args_equal (oldelt, elt))
12126 for (i = nargs; i--; )
12128 tree elt = TREE_VEC_ELT (tempargs, i);
12131 TREE_VEC_ELT (targs, i) = elt;
12137 /* PARM is a template class (perhaps with unbound template
12138 parameters). ARG is a fully instantiated type. If ARG can be
12139 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
12140 TARGS are as for unify. */
12143 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
12145 tree copy_of_targs;
12147 if (!CLASSTYPE_TEMPLATE_INFO (arg)
12148 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
12149 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
12152 /* We need to make a new template argument vector for the call to
12153 unify. If we used TARGS, we'd clutter it up with the result of
12154 the attempted unification, even if this class didn't work out.
12155 We also don't want to commit ourselves to all the unifications
12156 we've already done, since unification is supposed to be done on
12157 an argument-by-argument basis. In other words, consider the
12158 following pathological case:
12160 template <int I, int J, int K>
12163 template <int I, int J>
12164 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
12166 template <int I, int J, int K>
12167 void f(S<I, J, K>, S<I, I, I>);
12176 Now, by the time we consider the unification involving `s2', we
12177 already know that we must have `f<0, 0, 0>'. But, even though
12178 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
12179 because there are two ways to unify base classes of S<0, 1, 2>
12180 with S<I, I, I>. If we kept the already deduced knowledge, we
12181 would reject the possibility I=1. */
12182 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
12184 /* If unification failed, we're done. */
12185 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
12186 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
12192 /* Given a template type PARM and a class type ARG, find the unique
12193 base type in ARG that is an instance of PARM. We do not examine
12194 ARG itself; only its base-classes. If there is not exactly one
12195 appropriate base class, return NULL_TREE. PARM may be the type of
12196 a partial specialization, as well as a plain template type. Used
12200 get_template_base (tree tparms, tree targs, tree parm, tree arg)
12202 tree rval = NULL_TREE;
12205 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
12207 binfo = TYPE_BINFO (complete_type (arg));
12209 /* The type could not be completed. */
12212 /* Walk in inheritance graph order. The search order is not
12213 important, and this avoids multiple walks of virtual bases. */
12214 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
12216 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
12220 /* If there is more than one satisfactory baseclass, then:
12224 If they yield more than one possible deduced A, the type
12228 if (rval && !same_type_p (r, rval))
12238 /* Returns the level of DECL, which declares a template parameter. */
12241 template_decl_level (tree decl)
12243 switch (TREE_CODE (decl))
12246 case TEMPLATE_DECL:
12247 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
12250 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
12253 gcc_unreachable ();
12258 /* Decide whether ARG can be unified with PARM, considering only the
12259 cv-qualifiers of each type, given STRICT as documented for unify.
12260 Returns nonzero iff the unification is OK on that basis. */
12263 check_cv_quals_for_unify (int strict, tree arg, tree parm)
12265 int arg_quals = cp_type_quals (arg);
12266 int parm_quals = cp_type_quals (parm);
12268 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
12269 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
12271 /* Although a CVR qualifier is ignored when being applied to a
12272 substituted template parameter ([8.3.2]/1 for example), that
12273 does not apply during deduction [14.8.2.4]/1, (even though
12274 that is not explicitly mentioned, [14.8.2.4]/9 indicates
12275 this). Except when we're allowing additional CV qualifiers
12276 at the outer level [14.8.2.1]/3,1st bullet. */
12277 if ((TREE_CODE (arg) == REFERENCE_TYPE
12278 || TREE_CODE (arg) == FUNCTION_TYPE
12279 || TREE_CODE (arg) == METHOD_TYPE)
12280 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
12283 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
12284 && (parm_quals & TYPE_QUAL_RESTRICT))
12288 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
12289 && (arg_quals & parm_quals) != parm_quals)
12292 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
12293 && (parm_quals & arg_quals) != arg_quals)
12299 /* Determines the LEVEL and INDEX for the template parameter PARM. */
12301 template_parm_level_and_index (tree parm, int* level, int* index)
12303 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
12304 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
12305 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
12307 *index = TEMPLATE_TYPE_IDX (parm);
12308 *level = TEMPLATE_TYPE_LEVEL (parm);
12312 *index = TEMPLATE_PARM_IDX (parm);
12313 *level = TEMPLATE_PARM_LEVEL (parm);
12317 /* Unifies the remaining arguments in PACKED_ARGS with the pack
12318 expansion at the end of PACKED_PARMS. Returns 0 if the type
12319 deduction succeeds, 1 otherwise. STRICT is the same as in
12320 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
12321 call argument list. We'll need to adjust the arguments to make them
12322 types. SUBR tells us if this is from a recursive call to
12323 type_unification_real. */
12325 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
12326 tree packed_args, int strict, bool call_args_p,
12330 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
12331 tree pattern = PACK_EXPANSION_PATTERN (parm);
12332 tree pack, packs = NULL_TREE;
12333 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
12334 int len = TREE_VEC_LENGTH (packed_args);
12336 /* Determine the parameter packs we will be deducing from the
12337 pattern, and record their current deductions. */
12338 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
12339 pack; pack = TREE_CHAIN (pack))
12341 tree parm_pack = TREE_VALUE (pack);
12344 /* Determine the index and level of this parameter pack. */
12345 template_parm_level_and_index (parm_pack, &level, &idx);
12347 /* Keep track of the parameter packs and their corresponding
12349 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
12350 TREE_TYPE (packs) = make_tree_vec (len - start);
12353 /* Loop through all of the arguments that have not yet been
12354 unified and unify each with the pattern. */
12355 for (i = start; i < len; i++)
12357 tree parm = pattern;
12359 /* For each parameter pack, clear out the deduced value so that
12360 we can deduce it again. */
12361 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12364 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12366 TMPL_ARG (targs, level, idx) = NULL_TREE;
12369 /* Unify the pattern with the current argument. */
12371 tree arg = TREE_VEC_ELT (packed_args, i);
12372 tree arg_expr = NULL_TREE;
12373 int arg_strict = strict;
12374 bool skip_arg_p = false;
12380 /* This mirrors what we do in type_unification_real. */
12384 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
12385 | UNIFY_ALLOW_MORE_CV_QUAL
12386 | UNIFY_ALLOW_DERIVED);
12390 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
12394 sub_strict = UNIFY_ALLOW_NONE;
12398 gcc_unreachable ();
12403 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
12404 if (type_unknown_p (arg))
12406 /* [temp.deduct.type] A template-argument can be
12407 deduced from a pointer to function or pointer
12408 to member function argument if the set of
12409 overloaded functions does not contain function
12410 templates and at most one of a set of
12411 overloaded functions provides a unique
12414 if (resolve_overloaded_unification
12415 (tparms, targs, parm, arg, strict, sub_strict)
12424 arg = unlowered_expr_type (arg);
12425 if (arg == error_mark_node)
12430 arg_strict = sub_strict;
12434 maybe_adjust_types_for_deduction (strict, &parm, &arg,
12440 if (unify (tparms, targs, parm, arg, arg_strict))
12445 /* For each parameter pack, collect the deduced value. */
12446 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12449 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12451 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
12452 TMPL_ARG (targs, level, idx);
12456 /* Verify that the results of unification with the parameter packs
12457 produce results consistent with what we've seen before, and make
12458 the deduced argument packs available. */
12459 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12461 tree old_pack = TREE_VALUE (pack);
12462 tree new_args = TREE_TYPE (pack);
12464 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
12466 /* Prepend the explicit arguments onto NEW_ARGS. */
12467 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
12468 tree old_args = new_args;
12469 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
12470 int len = explicit_len + TREE_VEC_LENGTH (old_args);
12472 /* Copy the explicit arguments. */
12473 new_args = make_tree_vec (len);
12474 for (i = 0; i < explicit_len; i++)
12475 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
12477 /* Copy the deduced arguments. */
12478 for (; i < len; i++)
12479 TREE_VEC_ELT (new_args, i) =
12480 TREE_VEC_ELT (old_args, i - explicit_len);
12488 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12490 /* Build the deduced *_ARGUMENT_PACK. */
12491 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
12493 result = make_node (NONTYPE_ARGUMENT_PACK);
12494 TREE_TYPE (result) =
12495 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
12496 TREE_CONSTANT (result) = 1;
12499 result = make_node (TYPE_ARGUMENT_PACK);
12501 SET_ARGUMENT_PACK_ARGS (result, new_args);
12503 /* Note the deduced argument packs for this parameter
12505 TMPL_ARG (targs, level, idx) = result;
12507 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
12508 && (ARGUMENT_PACK_ARGS (old_pack)
12509 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
12511 /* We only had the explicitly-provided arguments before, but
12512 now we have a complete set of arguments. */
12514 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
12515 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12517 /* Keep the original deduced argument pack. */
12518 TMPL_ARG (targs, level, idx) = old_pack;
12520 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
12521 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
12522 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
12524 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
12526 /* Inconsistent unification of this parameter pack. */
12532 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12534 /* Keep the original deduced argument pack. */
12535 TMPL_ARG (targs, level, idx) = old_pack;
12542 /* Deduce the value of template parameters. TPARMS is the (innermost)
12543 set of template parameters to a template. TARGS is the bindings
12544 for those template parameters, as determined thus far; TARGS may
12545 include template arguments for outer levels of template parameters
12546 as well. PARM is a parameter to a template function, or a
12547 subcomponent of that parameter; ARG is the corresponding argument.
12548 This function attempts to match PARM with ARG in a manner
12549 consistent with the existing assignments in TARGS. If more values
12550 are deduced, then TARGS is updated.
12552 Returns 0 if the type deduction succeeds, 1 otherwise. The
12553 parameter STRICT is a bitwise or of the following flags:
12556 Require an exact match between PARM and ARG.
12557 UNIFY_ALLOW_MORE_CV_QUAL:
12558 Allow the deduced ARG to be more cv-qualified (by qualification
12559 conversion) than ARG.
12560 UNIFY_ALLOW_LESS_CV_QUAL:
12561 Allow the deduced ARG to be less cv-qualified than ARG.
12562 UNIFY_ALLOW_DERIVED:
12563 Allow the deduced ARG to be a template base class of ARG,
12564 or a pointer to a template base class of the type pointed to by
12566 UNIFY_ALLOW_INTEGER:
12567 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
12568 case for more information.
12569 UNIFY_ALLOW_OUTER_LEVEL:
12570 This is the outermost level of a deduction. Used to determine validity
12571 of qualification conversions. A valid qualification conversion must
12572 have const qualified pointers leading up to the inner type which
12573 requires additional CV quals, except at the outer level, where const
12574 is not required [conv.qual]. It would be normal to set this flag in
12575 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
12576 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
12577 This is the outermost level of a deduction, and PARM can be more CV
12578 qualified at this point.
12579 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
12580 This is the outermost level of a deduction, and PARM can be less CV
12581 qualified at this point. */
12584 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
12589 int strict_in = strict;
12591 /* I don't think this will do the right thing with respect to types.
12592 But the only case I've seen it in so far has been array bounds, where
12593 signedness is the only information lost, and I think that will be
12595 while (TREE_CODE (parm) == NOP_EXPR)
12596 parm = TREE_OPERAND (parm, 0);
12598 if (arg == error_mark_node)
12600 if (arg == unknown_type_node)
12601 /* We can't deduce anything from this, but we might get all the
12602 template args from other function args. */
12605 /* If PARM uses template parameters, then we can't bail out here,
12606 even if ARG == PARM, since we won't record unifications for the
12607 template parameters. We might need them if we're trying to
12608 figure out which of two things is more specialized. */
12609 if (arg == parm && !uses_template_parms (parm))
12612 /* Immediately reject some pairs that won't unify because of
12613 cv-qualification mismatches. */
12614 if (TREE_CODE (arg) == TREE_CODE (parm)
12616 /* It is the elements of the array which hold the cv quals of an array
12617 type, and the elements might be template type parms. We'll check
12618 when we recurse. */
12619 && TREE_CODE (arg) != ARRAY_TYPE
12620 /* We check the cv-qualifiers when unifying with template type
12621 parameters below. We want to allow ARG `const T' to unify with
12622 PARM `T' for example, when computing which of two templates
12623 is more specialized, for example. */
12624 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
12625 && !check_cv_quals_for_unify (strict_in, arg, parm))
12628 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
12629 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
12630 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
12631 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
12632 strict &= ~UNIFY_ALLOW_DERIVED;
12633 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
12634 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
12636 switch (TREE_CODE (parm))
12638 case TYPENAME_TYPE:
12640 case UNBOUND_CLASS_TEMPLATE:
12641 /* In a type which contains a nested-name-specifier, template
12642 argument values cannot be deduced for template parameters used
12643 within the nested-name-specifier. */
12646 case TEMPLATE_TYPE_PARM:
12647 case TEMPLATE_TEMPLATE_PARM:
12648 case BOUND_TEMPLATE_TEMPLATE_PARM:
12649 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
12650 if (tparm == error_mark_node)
12653 if (TEMPLATE_TYPE_LEVEL (parm)
12654 != template_decl_level (tparm))
12655 /* The PARM is not one we're trying to unify. Just check
12656 to see if it matches ARG. */
12657 return (TREE_CODE (arg) == TREE_CODE (parm)
12658 && same_type_p (parm, arg)) ? 0 : 1;
12659 idx = TEMPLATE_TYPE_IDX (parm);
12660 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
12661 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
12663 /* Check for mixed types and values. */
12664 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
12665 && TREE_CODE (tparm) != TYPE_DECL)
12666 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
12667 && TREE_CODE (tparm) != TEMPLATE_DECL))
12670 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
12672 /* ARG must be constructed from a template class or a template
12673 template parameter. */
12674 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
12675 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
12679 tree parmvec = TYPE_TI_ARGS (parm);
12680 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
12682 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
12685 /* The resolution to DR150 makes clear that default
12686 arguments for an N-argument may not be used to bind T
12687 to a template template parameter with fewer than N
12688 parameters. It is not safe to permit the binding of
12689 default arguments as an extension, as that may change
12690 the meaning of a conforming program. Consider:
12692 struct Dense { static const unsigned int dim = 1; };
12694 template <template <typename> class View,
12696 void operator+(float, View<Block> const&);
12698 template <typename Block,
12699 unsigned int Dim = Block::dim>
12700 struct Lvalue_proxy { operator float() const; };
12704 Lvalue_proxy<Dense> p;
12709 Here, if Lvalue_proxy is permitted to bind to View, then
12710 the global operator+ will be used; if they are not, the
12711 Lvalue_proxy will be converted to float. */
12712 if (coerce_template_parms (argtmplvec, parmvec,
12713 TYPE_TI_TEMPLATE (parm),
12715 /*require_all_args=*/true,
12716 /*use_default_args=*/false)
12717 == error_mark_node)
12720 /* Deduce arguments T, i from TT<T> or TT<i>.
12721 We check each element of PARMVEC and ARGVEC individually
12722 rather than the whole TREE_VEC since they can have
12723 different number of elements. */
12725 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
12727 if (unify (tparms, targs,
12728 TREE_VEC_ELT (parmvec, i),
12729 TREE_VEC_ELT (argvec, i),
12734 arg = TYPE_TI_TEMPLATE (arg);
12736 /* Fall through to deduce template name. */
12739 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
12740 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
12742 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
12744 /* Simple cases: Value already set, does match or doesn't. */
12745 if (targ != NULL_TREE && template_args_equal (targ, arg))
12752 /* If PARM is `const T' and ARG is only `int', we don't have
12753 a match unless we are allowing additional qualification.
12754 If ARG is `const int' and PARM is just `T' that's OK;
12755 that binds `const int' to `T'. */
12756 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
12760 /* Consider the case where ARG is `const volatile int' and
12761 PARM is `const T'. Then, T should be `volatile int'. */
12762 arg = cp_build_qualified_type_real
12763 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
12764 if (arg == error_mark_node)
12767 /* Simple cases: Value already set, does match or doesn't. */
12768 if (targ != NULL_TREE && same_type_p (targ, arg))
12773 /* Make sure that ARG is not a variable-sized array. (Note
12774 that were talking about variable-sized arrays (like
12775 `int[n]'), rather than arrays of unknown size (like
12776 `int[]').) We'll get very confused by such a type since
12777 the bound of the array will not be computable in an
12778 instantiation. Besides, such types are not allowed in
12779 ISO C++, so we can do as we please here. */
12780 if (variably_modified_type_p (arg, NULL_TREE))
12784 /* If ARG is a parameter pack or an expansion, we cannot unify
12785 against it unless PARM is also a parameter pack. */
12786 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
12787 && !template_parameter_pack_p (parm))
12790 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
12793 case TEMPLATE_PARM_INDEX:
12794 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
12795 if (tparm == error_mark_node)
12798 if (TEMPLATE_PARM_LEVEL (parm)
12799 != template_decl_level (tparm))
12800 /* The PARM is not one we're trying to unify. Just check
12801 to see if it matches ARG. */
12802 return !(TREE_CODE (arg) == TREE_CODE (parm)
12803 && cp_tree_equal (parm, arg));
12805 idx = TEMPLATE_PARM_IDX (parm);
12806 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
12809 return !cp_tree_equal (targ, arg);
12811 /* [temp.deduct.type] If, in the declaration of a function template
12812 with a non-type template-parameter, the non-type
12813 template-parameter is used in an expression in the function
12814 parameter-list and, if the corresponding template-argument is
12815 deduced, the template-argument type shall match the type of the
12816 template-parameter exactly, except that a template-argument
12817 deduced from an array bound may be of any integral type.
12818 The non-type parameter might use already deduced type parameters. */
12819 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
12820 if (!TREE_TYPE (arg))
12821 /* Template-parameter dependent expression. Just accept it for now.
12822 It will later be processed in convert_template_argument. */
12824 else if (same_type_p (TREE_TYPE (arg), tparm))
12826 else if ((strict & UNIFY_ALLOW_INTEGER)
12827 && (TREE_CODE (tparm) == INTEGER_TYPE
12828 || TREE_CODE (tparm) == BOOLEAN_TYPE))
12829 /* Convert the ARG to the type of PARM; the deduced non-type
12830 template argument must exactly match the types of the
12831 corresponding parameter. */
12832 arg = fold (build_nop (TREE_TYPE (parm), arg));
12833 else if (uses_template_parms (tparm))
12834 /* We haven't deduced the type of this parameter yet. Try again
12840 /* If ARG is a parameter pack or an expansion, we cannot unify
12841 against it unless PARM is also a parameter pack. */
12842 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
12843 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
12846 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
12851 /* A pointer-to-member constant can be unified only with
12852 another constant. */
12853 if (TREE_CODE (arg) != PTRMEM_CST)
12856 /* Just unify the class member. It would be useless (and possibly
12857 wrong, depending on the strict flags) to unify also
12858 PTRMEM_CST_CLASS, because we want to be sure that both parm and
12859 arg refer to the same variable, even if through different
12860 classes. For instance:
12862 struct A { int x; };
12865 Unification of &A::x and &B::x must succeed. */
12866 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
12867 PTRMEM_CST_MEMBER (arg), strict);
12872 if (TREE_CODE (arg) != POINTER_TYPE)
12875 /* [temp.deduct.call]
12877 A can be another pointer or pointer to member type that can
12878 be converted to the deduced A via a qualification
12879 conversion (_conv.qual_).
12881 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
12882 This will allow for additional cv-qualification of the
12883 pointed-to types if appropriate. */
12885 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
12886 /* The derived-to-base conversion only persists through one
12887 level of pointers. */
12888 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
12890 return unify (tparms, targs, TREE_TYPE (parm),
12891 TREE_TYPE (arg), strict);
12894 case REFERENCE_TYPE:
12895 if (TREE_CODE (arg) != REFERENCE_TYPE)
12897 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
12898 strict & UNIFY_ALLOW_MORE_CV_QUAL);
12901 if (TREE_CODE (arg) != ARRAY_TYPE)
12903 if ((TYPE_DOMAIN (parm) == NULL_TREE)
12904 != (TYPE_DOMAIN (arg) == NULL_TREE))
12906 if (TYPE_DOMAIN (parm) != NULL_TREE)
12913 /* Our representation of array types uses "N - 1" as the
12914 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
12915 not an integer constant. We cannot unify arbitrarily
12916 complex expressions, so we eliminate the MINUS_EXPRs
12918 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
12919 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
12922 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
12923 parm_max = TREE_OPERAND (parm_max, 0);
12925 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
12926 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
12929 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
12930 trying to unify the type of a variable with the type
12931 of a template parameter. For example:
12933 template <unsigned int N>
12934 void f (char (&) [N]);
12941 Here, the type of the ARG will be "int [g(i)]", and
12942 may be a SAVE_EXPR, etc. */
12943 if (TREE_CODE (arg_max) != MINUS_EXPR)
12945 arg_max = TREE_OPERAND (arg_max, 0);
12948 /* If only one of the bounds used a MINUS_EXPR, compensate
12949 by adding one to the other bound. */
12950 if (parm_cst && !arg_cst)
12951 parm_max = fold_build2 (PLUS_EXPR,
12955 else if (arg_cst && !parm_cst)
12956 arg_max = fold_build2 (PLUS_EXPR,
12961 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
12964 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
12965 strict & UNIFY_ALLOW_MORE_CV_QUAL);
12972 case ENUMERAL_TYPE:
12974 if (TREE_CODE (arg) != TREE_CODE (parm))
12977 /* We have already checked cv-qualification at the top of the
12979 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
12982 /* As far as unification is concerned, this wins. Later checks
12983 will invalidate it if necessary. */
12986 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
12987 /* Type INTEGER_CST can come from ordinary constant template args. */
12989 while (TREE_CODE (arg) == NOP_EXPR)
12990 arg = TREE_OPERAND (arg, 0);
12992 if (TREE_CODE (arg) != INTEGER_CST)
12994 return !tree_int_cst_equal (parm, arg);
12999 if (TREE_CODE (arg) != TREE_VEC)
13001 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
13003 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
13004 if (unify (tparms, targs,
13005 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
13013 if (TREE_CODE (arg) != TREE_CODE (parm))
13016 if (TYPE_PTRMEMFUNC_P (parm))
13018 if (!TYPE_PTRMEMFUNC_P (arg))
13021 return unify (tparms, targs,
13022 TYPE_PTRMEMFUNC_FN_TYPE (parm),
13023 TYPE_PTRMEMFUNC_FN_TYPE (arg),
13027 if (CLASSTYPE_TEMPLATE_INFO (parm))
13029 tree t = NULL_TREE;
13031 if (strict_in & UNIFY_ALLOW_DERIVED)
13033 /* First, we try to unify the PARM and ARG directly. */
13034 t = try_class_unification (tparms, targs,
13039 /* Fallback to the special case allowed in
13040 [temp.deduct.call]:
13042 If P is a class, and P has the form
13043 template-id, then A can be a derived class of
13044 the deduced A. Likewise, if P is a pointer to
13045 a class of the form template-id, A can be a
13046 pointer to a derived class pointed to by the
13048 t = get_template_base (tparms, targs, parm, arg);
13054 else if (CLASSTYPE_TEMPLATE_INFO (arg)
13055 && (CLASSTYPE_TI_TEMPLATE (parm)
13056 == CLASSTYPE_TI_TEMPLATE (arg)))
13057 /* Perhaps PARM is something like S<U> and ARG is S<int>.
13058 Then, we should unify `int' and `U'. */
13061 /* There's no chance of unification succeeding. */
13064 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
13065 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
13067 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
13072 case FUNCTION_TYPE:
13073 if (TREE_CODE (arg) != TREE_CODE (parm))
13076 /* CV qualifications for methods can never be deduced, they must
13077 match exactly. We need to check them explicitly here,
13078 because type_unification_real treats them as any other
13079 cvqualified parameter. */
13080 if (TREE_CODE (parm) == METHOD_TYPE
13081 && (!check_cv_quals_for_unify
13083 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
13084 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
13087 if (unify (tparms, targs, TREE_TYPE (parm),
13088 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
13090 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
13091 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
13095 /* Unify a pointer to member with a pointer to member function, which
13096 deduces the type of the member as a function type. */
13097 if (TYPE_PTRMEMFUNC_P (arg))
13101 cp_cv_quals cv_quals;
13103 /* Check top-level cv qualifiers */
13104 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
13107 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
13108 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
13111 /* Determine the type of the function we are unifying against. */
13112 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
13114 build_function_type (TREE_TYPE (method_type),
13115 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
13117 /* Extract the cv-qualifiers of the member function from the
13118 implicit object parameter and place them on the function
13119 type to be restored later. */
13121 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
13122 fntype = build_qualified_type (fntype, cv_quals);
13123 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
13126 if (TREE_CODE (arg) != OFFSET_TYPE)
13128 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
13129 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
13131 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
13135 if (DECL_TEMPLATE_PARM_P (parm))
13136 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
13137 if (arg != integral_constant_value (parm))
13142 case TEMPLATE_DECL:
13143 /* Matched cases are handled by the ARG == PARM test above. */
13146 case TYPE_ARGUMENT_PACK:
13147 case NONTYPE_ARGUMENT_PACK:
13149 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
13150 tree packed_args = ARGUMENT_PACK_ARGS (arg);
13151 int i, len = TREE_VEC_LENGTH (packed_parms);
13152 int argslen = TREE_VEC_LENGTH (packed_args);
13153 int parm_variadic_p = 0;
13155 /* Check if the parameters end in a pack, making them variadic. */
13157 && PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, len - 1)))
13158 parm_variadic_p = 1;
13160 /* If we don't have enough arguments to satisfy the parameters
13161 (not counting the pack expression at the end), or we have
13162 too many arguments for a parameter list that doesn't end in
13163 a pack expression, we can't unify. */
13164 if (argslen < (len - parm_variadic_p)
13165 || (argslen > len && !parm_variadic_p))
13168 /* Unify all of the parameters that precede the (optional)
13169 pack expression. */
13170 for (i = 0; i < len - parm_variadic_p; ++i)
13172 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
13173 TREE_VEC_ELT (packed_args, i), strict))
13177 if (parm_variadic_p)
13178 return unify_pack_expansion (tparms, targs,
13179 packed_parms, packed_args,
13180 strict, /*call_args_p=*/false,
13188 case DECLTYPE_TYPE:
13189 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
13194 /* Unification fails if we hit an error node. */
13198 gcc_assert (EXPR_P (parm));
13200 /* We must be looking at an expression. This can happen with
13204 void foo(S<I>, S<I + 2>);
13206 This is a "nondeduced context":
13210 The nondeduced contexts are:
13212 --A type that is a template-id in which one or more of
13213 the template-arguments is an expression that references
13214 a template-parameter.
13216 In these cases, we assume deduction succeeded, but don't
13217 actually infer any unifications. */
13219 if (!uses_template_parms (parm)
13220 && !template_args_equal (parm, arg))
13227 /* Note that DECL can be defined in this translation unit, if
13231 mark_definable (tree decl)
13234 DECL_NOT_REALLY_EXTERN (decl) = 1;
13235 FOR_EACH_CLONE (clone, decl)
13236 DECL_NOT_REALLY_EXTERN (clone) = 1;
13239 /* Called if RESULT is explicitly instantiated, or is a member of an
13240 explicitly instantiated class. */
13243 mark_decl_instantiated (tree result, int extern_p)
13245 SET_DECL_EXPLICIT_INSTANTIATION (result);
13247 /* If this entity has already been written out, it's too late to
13248 make any modifications. */
13249 if (TREE_ASM_WRITTEN (result))
13252 if (TREE_CODE (result) != FUNCTION_DECL)
13253 /* The TREE_PUBLIC flag for function declarations will have been
13254 set correctly by tsubst. */
13255 TREE_PUBLIC (result) = 1;
13257 /* This might have been set by an earlier implicit instantiation. */
13258 DECL_COMDAT (result) = 0;
13261 DECL_NOT_REALLY_EXTERN (result) = 0;
13264 mark_definable (result);
13265 /* Always make artificials weak. */
13266 if (DECL_ARTIFICIAL (result) && flag_weak)
13267 comdat_linkage (result);
13268 /* For WIN32 we also want to put explicit instantiations in
13269 linkonce sections. */
13270 else if (TREE_PUBLIC (result))
13271 maybe_make_one_only (result);
13274 /* If EXTERN_P, then this function will not be emitted -- unless
13275 followed by an explicit instantiation, at which point its linkage
13276 will be adjusted. If !EXTERN_P, then this function will be
13277 emitted here. In neither circumstance do we want
13278 import_export_decl to adjust the linkage. */
13279 DECL_INTERFACE_KNOWN (result) = 1;
13282 /* Given two function templates PAT1 and PAT2, return:
13284 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
13285 -1 if PAT2 is more specialized than PAT1.
13286 0 if neither is more specialized.
13288 LEN indicates the number of parameters we should consider
13289 (defaulted parameters should not be considered).
13291 The 1998 std underspecified function template partial ordering, and
13292 DR214 addresses the issue. We take pairs of arguments, one from
13293 each of the templates, and deduce them against each other. One of
13294 the templates will be more specialized if all the *other*
13295 template's arguments deduce against its arguments and at least one
13296 of its arguments *does* *not* deduce against the other template's
13297 corresponding argument. Deduction is done as for class templates.
13298 The arguments used in deduction have reference and top level cv
13299 qualifiers removed. Iff both arguments were originally reference
13300 types *and* deduction succeeds in both directions, the template
13301 with the more cv-qualified argument wins for that pairing (if
13302 neither is more cv-qualified, they both are equal). Unlike regular
13303 deduction, after all the arguments have been deduced in this way,
13304 we do *not* verify the deduced template argument values can be
13305 substituted into non-deduced contexts, nor do we have to verify
13306 that all template arguments have been deduced. */
13309 more_specialized_fn (tree pat1, tree pat2, int len)
13311 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
13312 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
13313 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
13314 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
13315 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
13316 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
13317 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
13318 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
13322 /* Remove the this parameter from non-static member functions. If
13323 one is a non-static member function and the other is not a static
13324 member function, remove the first parameter from that function
13325 also. This situation occurs for operator functions where we
13326 locate both a member function (with this pointer) and non-member
13327 operator (with explicit first operand). */
13328 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
13330 len--; /* LEN is the number of significant arguments for DECL1 */
13331 args1 = TREE_CHAIN (args1);
13332 if (!DECL_STATIC_FUNCTION_P (decl2))
13333 args2 = TREE_CHAIN (args2);
13335 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
13337 args2 = TREE_CHAIN (args2);
13338 if (!DECL_STATIC_FUNCTION_P (decl1))
13341 args1 = TREE_CHAIN (args1);
13345 /* If only one is a conversion operator, they are unordered. */
13346 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
13349 /* Consider the return type for a conversion function */
13350 if (DECL_CONV_FN_P (decl1))
13352 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
13353 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
13357 processing_template_decl++;
13361 tree arg1 = TREE_VALUE (args1);
13362 tree arg2 = TREE_VALUE (args2);
13363 int deduce1, deduce2;
13367 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
13368 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
13370 /* When both arguments are pack expansions, we need only
13371 unify the patterns themselves. */
13372 arg1 = PACK_EXPANSION_PATTERN (arg1);
13373 arg2 = PACK_EXPANSION_PATTERN (arg2);
13375 /* This is the last comparison we need to do. */
13379 if (TREE_CODE (arg1) == REFERENCE_TYPE)
13381 arg1 = TREE_TYPE (arg1);
13382 quals1 = cp_type_quals (arg1);
13385 if (TREE_CODE (arg2) == REFERENCE_TYPE)
13387 arg2 = TREE_TYPE (arg2);
13388 quals2 = cp_type_quals (arg2);
13391 if ((quals1 < 0) != (quals2 < 0))
13393 /* Only of the args is a reference, see if we should apply
13394 array/function pointer decay to it. This is not part of
13395 DR214, but is, IMHO, consistent with the deduction rules
13396 for the function call itself, and with our earlier
13397 implementation of the underspecified partial ordering
13398 rules. (nathan). */
13401 switch (TREE_CODE (arg1))
13404 arg1 = TREE_TYPE (arg1);
13406 case FUNCTION_TYPE:
13407 arg1 = build_pointer_type (arg1);
13416 switch (TREE_CODE (arg2))
13419 arg2 = TREE_TYPE (arg2);
13421 case FUNCTION_TYPE:
13422 arg2 = build_pointer_type (arg2);
13431 arg1 = TYPE_MAIN_VARIANT (arg1);
13432 arg2 = TYPE_MAIN_VARIANT (arg2);
13434 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
13436 int i, len2 = list_length (args2);
13437 tree parmvec = make_tree_vec (1);
13438 tree argvec = make_tree_vec (len2);
13441 /* Setup the parameter vector, which contains only ARG1. */
13442 TREE_VEC_ELT (parmvec, 0) = arg1;
13444 /* Setup the argument vector, which contains the remaining
13446 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
13447 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
13449 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
13450 argvec, UNIFY_ALLOW_NONE,
13451 /*call_args_p=*/false,
13454 /* We cannot deduce in the other direction, because ARG1 is
13455 a pack expansion but ARG2 is not. */
13458 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
13460 int i, len1 = list_length (args1);
13461 tree parmvec = make_tree_vec (1);
13462 tree argvec = make_tree_vec (len1);
13465 /* Setup the parameter vector, which contains only ARG1. */
13466 TREE_VEC_ELT (parmvec, 0) = arg2;
13468 /* Setup the argument vector, which contains the remaining
13470 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
13471 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
13473 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
13474 argvec, UNIFY_ALLOW_NONE,
13475 /*call_args_p=*/false,
13478 /* We cannot deduce in the other direction, because ARG2 is
13479 a pack expansion but ARG1 is not.*/
13485 /* The normal case, where neither argument is a pack
13487 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
13488 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
13495 if (better1 < 0 && better2 < 0)
13496 /* We've failed to deduce something in either direction.
13497 These must be unordered. */
13500 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
13502 /* Deduces in both directions, see if quals can
13503 disambiguate. Pretend the worse one failed to deduce. */
13504 if ((quals1 & quals2) == quals2)
13506 if ((quals1 & quals2) == quals1)
13509 if (deduce1 && !deduce2 && !better2)
13511 if (deduce2 && !deduce1 && !better1)
13514 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
13515 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
13516 /* We have already processed all of the arguments in our
13517 handing of the pack expansion type. */
13520 args1 = TREE_CHAIN (args1);
13521 args2 = TREE_CHAIN (args2);
13524 processing_template_decl--;
13526 /* All things being equal, if the next argument is a pack expansion
13527 for one function but not for the other, prefer the
13528 non-variadic function. */
13529 if ((better1 > 0) - (better2 > 0) == 0
13530 && args1 && TREE_VALUE (args1)
13531 && args2 && TREE_VALUE (args2))
13533 if (TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION)
13534 return TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION ? 0 : -1;
13535 else if (TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION)
13539 return (better1 > 0) - (better2 > 0);
13542 /* Determine which of two partial specializations is more specialized.
13544 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
13545 to the first partial specialization. The TREE_VALUE is the
13546 innermost set of template parameters for the partial
13547 specialization. PAT2 is similar, but for the second template.
13549 Return 1 if the first partial specialization is more specialized;
13550 -1 if the second is more specialized; 0 if neither is more
13553 See [temp.class.order] for information about determining which of
13554 two templates is more specialized. */
13557 more_specialized_class (tree pat1, tree pat2)
13562 bool any_deductions = false;
13564 tmpl1 = TREE_TYPE (pat1);
13565 tmpl2 = TREE_TYPE (pat2);
13567 /* Just like what happens for functions, if we are ordering between
13568 different class template specializations, we may encounter dependent
13569 types in the arguments, and we need our dependency check functions
13570 to behave correctly. */
13571 ++processing_template_decl;
13572 targs = get_class_bindings (TREE_VALUE (pat1),
13573 CLASSTYPE_TI_ARGS (tmpl1),
13574 CLASSTYPE_TI_ARGS (tmpl2));
13578 any_deductions = true;
13581 targs = get_class_bindings (TREE_VALUE (pat2),
13582 CLASSTYPE_TI_ARGS (tmpl2),
13583 CLASSTYPE_TI_ARGS (tmpl1));
13587 any_deductions = true;
13589 --processing_template_decl;
13591 /* In the case of a tie where at least one of the class templates
13592 has a parameter pack at the end, the template with the most
13593 non-packed parameters wins. */
13596 && (template_args_variadic_p (TREE_PURPOSE (pat1))
13597 || template_args_variadic_p (TREE_PURPOSE (pat2))))
13599 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
13600 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
13601 int len1 = TREE_VEC_LENGTH (args1);
13602 int len2 = TREE_VEC_LENGTH (args2);
13604 /* We don't count the pack expansion at the end. */
13605 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
13607 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
13612 else if (len1 < len2)
13619 /* Return the template arguments that will produce the function signature
13620 DECL from the function template FN, with the explicit template
13621 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
13622 also match. Return NULL_TREE if no satisfactory arguments could be
13626 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
13628 int ntparms = DECL_NTPARMS (fn);
13629 tree targs = make_tree_vec (ntparms);
13631 tree decl_arg_types;
13633 /* Substitute the explicit template arguments into the type of DECL.
13634 The call to fn_type_unification will handle substitution into the
13636 decl_type = TREE_TYPE (decl);
13637 if (explicit_args && uses_template_parms (decl_type))
13640 tree converted_args;
13642 if (DECL_TEMPLATE_INFO (decl))
13643 tmpl = DECL_TI_TEMPLATE (decl);
13645 /* We can get here for some invalid specializations. */
13649 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
13650 explicit_args, NULL_TREE,
13652 /*require_all_args=*/false,
13653 /*use_default_args=*/false);
13654 if (converted_args == error_mark_node)
13657 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
13658 if (decl_type == error_mark_node)
13662 /* Never do unification on the 'this' parameter. */
13663 decl_arg_types = skip_artificial_parms_for (decl,
13664 TYPE_ARG_TYPES (decl_type));
13666 if (fn_type_unification (fn, explicit_args, targs,
13668 (check_rettype || DECL_CONV_FN_P (fn)
13669 ? TREE_TYPE (decl_type) : NULL_TREE),
13670 DEDUCE_EXACT, LOOKUP_NORMAL))
13676 /* Return the innermost template arguments that, when applied to a
13677 template specialization whose innermost template parameters are
13678 TPARMS, and whose specialization arguments are PARMS, yield the
13681 For example, suppose we have:
13683 template <class T, class U> struct S {};
13684 template <class T> struct S<T*, int> {};
13686 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
13687 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
13688 int}. The resulting vector will be {double}, indicating that `T'
13689 is bound to `double'. */
13692 get_class_bindings (tree tparms, tree spec_args, tree args)
13694 int i, ntparms = TREE_VEC_LENGTH (tparms);
13696 tree innermost_deduced_args;
13698 innermost_deduced_args = make_tree_vec (ntparms);
13699 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
13701 deduced_args = copy_node (args);
13702 SET_TMPL_ARGS_LEVEL (deduced_args,
13703 TMPL_ARGS_DEPTH (deduced_args),
13704 innermost_deduced_args);
13707 deduced_args = innermost_deduced_args;
13709 if (unify (tparms, deduced_args,
13710 INNERMOST_TEMPLATE_ARGS (spec_args),
13711 INNERMOST_TEMPLATE_ARGS (args),
13715 for (i = 0; i < ntparms; ++i)
13716 if (! TREE_VEC_ELT (innermost_deduced_args, i))
13719 /* Verify that nondeduced template arguments agree with the type
13720 obtained from argument deduction.
13724 struct A { typedef int X; };
13725 template <class T, class U> struct C {};
13726 template <class T> struct C<T, typename T::X> {};
13728 Then with the instantiation `C<A, int>', we can deduce that
13729 `T' is `A' but unify () does not check whether `typename T::X'
13731 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
13732 if (spec_args == error_mark_node
13733 /* We only need to check the innermost arguments; the other
13734 arguments will always agree. */
13735 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
13736 INNERMOST_TEMPLATE_ARGS (args)))
13739 return deduced_args;
13742 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
13743 Return the TREE_LIST node with the most specialized template, if
13744 any. If there is no most specialized template, the error_mark_node
13747 Note that this function does not look at, or modify, the
13748 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
13749 returned is one of the elements of INSTANTIATIONS, callers may
13750 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
13751 and retrieve it from the value returned. */
13754 most_specialized_instantiation (tree templates)
13758 ++processing_template_decl;
13761 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
13765 if (get_bindings (TREE_VALUE (champ),
13766 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
13767 NULL_TREE, /*check_ret=*/false))
13770 if (get_bindings (TREE_VALUE (fn),
13771 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
13772 NULL_TREE, /*check_ret=*/false))
13779 /* Equally specialized, move to next function. If there
13780 is no next function, nothing's most specialized. */
13781 fn = TREE_CHAIN (fn);
13789 /* Now verify that champ is better than everything earlier in the
13790 instantiation list. */
13791 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
13792 if (get_bindings (TREE_VALUE (champ),
13793 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
13794 NULL_TREE, /*check_ret=*/false)
13795 || !get_bindings (TREE_VALUE (fn),
13796 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
13797 NULL_TREE, /*check_ret=*/false))
13803 processing_template_decl--;
13806 return error_mark_node;
13811 /* If DECL is a specialization of some template, return the most
13812 general such template. Otherwise, returns NULL_TREE.
13814 For example, given:
13816 template <class T> struct S { template <class U> void f(U); };
13818 if TMPL is `template <class U> void S<int>::f(U)' this will return
13819 the full template. This function will not trace past partial
13820 specializations, however. For example, given in addition:
13822 template <class T> struct S<T*> { template <class U> void f(U); };
13824 if TMPL is `template <class U> void S<int*>::f(U)' this will return
13825 `template <class T> template <class U> S<T*>::f(U)'. */
13828 most_general_template (tree decl)
13830 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
13831 an immediate specialization. */
13832 if (TREE_CODE (decl) == FUNCTION_DECL)
13834 if (DECL_TEMPLATE_INFO (decl)) {
13835 decl = DECL_TI_TEMPLATE (decl);
13837 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
13838 template friend. */
13839 if (TREE_CODE (decl) != TEMPLATE_DECL)
13845 /* Look for more and more general templates. */
13846 while (DECL_TEMPLATE_INFO (decl))
13848 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
13849 (See cp-tree.h for details.) */
13850 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
13853 if (CLASS_TYPE_P (TREE_TYPE (decl))
13854 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
13857 /* Stop if we run into an explicitly specialized class template. */
13858 if (!DECL_NAMESPACE_SCOPE_P (decl)
13859 && DECL_CONTEXT (decl)
13860 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
13863 decl = DECL_TI_TEMPLATE (decl);
13869 /* Return the most specialized of the class template partial
13870 specializations of TMPL which can produce TYPE, a specialization of
13871 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
13872 a _TYPE node corresponding to the partial specialization, while the
13873 TREE_PURPOSE is the set of template arguments that must be
13874 substituted into the TREE_TYPE in order to generate TYPE.
13876 If the choice of partial specialization is ambiguous, a diagnostic
13877 is issued, and the error_mark_node is returned. If there are no
13878 partial specializations of TMPL matching TYPE, then NULL_TREE is
13882 most_specialized_class (tree type, tree tmpl)
13884 tree list = NULL_TREE;
13890 tree outer_args = NULL_TREE;
13892 tmpl = most_general_template (tmpl);
13893 args = CLASSTYPE_TI_ARGS (type);
13895 /* For determining which partial specialization to use, only the
13896 innermost args are interesting. */
13897 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
13899 outer_args = strip_innermost_template_args (args, 1);
13900 args = INNERMOST_TEMPLATE_ARGS (args);
13903 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
13905 tree partial_spec_args;
13907 tree parms = TREE_VALUE (t);
13909 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
13914 ++processing_template_decl;
13916 /* Discard the outer levels of args, and then substitute in the
13917 template args from the enclosing class. */
13918 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
13919 partial_spec_args = tsubst_template_args
13920 (partial_spec_args, outer_args, tf_none, NULL_TREE);
13922 /* PARMS already refers to just the innermost parms, but the
13923 template parms in partial_spec_args had their levels lowered
13924 by tsubst, so we need to do the same for the parm list. We
13925 can't just tsubst the TREE_VEC itself, as tsubst wants to
13926 treat a TREE_VEC as an argument vector. */
13927 parms = copy_node (parms);
13928 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
13929 TREE_VEC_ELT (parms, i) =
13930 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
13932 --processing_template_decl;
13934 spec_args = get_class_bindings (parms,
13940 spec_args = add_to_template_args (outer_args, spec_args);
13941 list = tree_cons (spec_args, TREE_VALUE (t), list);
13942 TREE_TYPE (list) = TREE_TYPE (t);
13949 ambiguous_p = false;
13952 t = TREE_CHAIN (t);
13953 for (; t; t = TREE_CHAIN (t))
13955 fate = more_specialized_class (champ, t);
13962 t = TREE_CHAIN (t);
13965 ambiguous_p = true;
13974 for (t = list; t && t != champ; t = TREE_CHAIN (t))
13976 fate = more_specialized_class (champ, t);
13979 ambiguous_p = true;
13986 const char *str = "candidates are:";
13987 error ("ambiguous class template instantiation for %q#T", type);
13988 for (t = list; t; t = TREE_CHAIN (t))
13990 error ("%s %+#T", str, TREE_TYPE (t));
13993 return error_mark_node;
13999 /* Explicitly instantiate DECL. */
14002 do_decl_instantiation (tree decl, tree storage)
14004 tree result = NULL_TREE;
14007 if (!decl || decl == error_mark_node)
14008 /* An error occurred, for which grokdeclarator has already issued
14009 an appropriate message. */
14011 else if (! DECL_LANG_SPECIFIC (decl))
14013 error ("explicit instantiation of non-template %q#D", decl);
14016 else if (TREE_CODE (decl) == VAR_DECL)
14018 /* There is an asymmetry here in the way VAR_DECLs and
14019 FUNCTION_DECLs are handled by grokdeclarator. In the case of
14020 the latter, the DECL we get back will be marked as a
14021 template instantiation, and the appropriate
14022 DECL_TEMPLATE_INFO will be set up. This does not happen for
14023 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
14024 should handle VAR_DECLs as it currently handles
14026 if (!DECL_CLASS_SCOPE_P (decl))
14028 error ("%qD is not a static data member of a class template", decl);
14031 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
14032 if (!result || TREE_CODE (result) != VAR_DECL)
14034 error ("no matching template for %qD found", decl);
14037 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
14039 error ("type %qT for explicit instantiation %qD does not match "
14040 "declared type %qT", TREE_TYPE (result), decl,
14045 else if (TREE_CODE (decl) != FUNCTION_DECL)
14047 error ("explicit instantiation of %q#D", decl);
14053 /* Check for various error cases. Note that if the explicit
14054 instantiation is valid the RESULT will currently be marked as an
14055 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
14056 until we get here. */
14058 if (DECL_TEMPLATE_SPECIALIZATION (result))
14060 /* DR 259 [temp.spec].
14062 Both an explicit instantiation and a declaration of an explicit
14063 specialization shall not appear in a program unless the explicit
14064 instantiation follows a declaration of the explicit specialization.
14066 For a given set of template parameters, if an explicit
14067 instantiation of a template appears after a declaration of an
14068 explicit specialization for that template, the explicit
14069 instantiation has no effect. */
14072 else if (DECL_EXPLICIT_INSTANTIATION (result))
14076 No program shall explicitly instantiate any template more
14079 We check DECL_NOT_REALLY_EXTERN so as not to complain when
14080 the first instantiation was `extern' and the second is not,
14081 and EXTERN_P for the opposite case. */
14082 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
14083 pedwarn ("duplicate explicit instantiation of %q#D", result);
14084 /* If an "extern" explicit instantiation follows an ordinary
14085 explicit instantiation, the template is instantiated. */
14089 else if (!DECL_IMPLICIT_INSTANTIATION (result))
14091 error ("no matching template for %qD found", result);
14094 else if (!DECL_TEMPLATE_INFO (result))
14096 pedwarn ("explicit instantiation of non-template %q#D", result);
14100 if (storage == NULL_TREE)
14102 else if (storage == ridpointers[(int) RID_EXTERN])
14104 if (pedantic && !in_system_header)
14105 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
14110 error ("storage class %qD applied to template instantiation", storage);
14112 check_explicit_instantiation_namespace (result);
14113 mark_decl_instantiated (result, extern_p);
14115 instantiate_decl (result, /*defer_ok=*/1,
14116 /*expl_inst_class_mem_p=*/false);
14120 mark_class_instantiated (tree t, int extern_p)
14122 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
14123 SET_CLASSTYPE_INTERFACE_KNOWN (t);
14124 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
14125 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
14128 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
14129 rest_of_type_compilation (t, 1);
14133 /* Called from do_type_instantiation through binding_table_foreach to
14134 do recursive instantiation for the type bound in ENTRY. */
14136 bt_instantiate_type_proc (binding_entry entry, void *data)
14138 tree storage = *(tree *) data;
14140 if (IS_AGGR_TYPE (entry->type)
14141 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
14142 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
14145 /* Called from do_type_instantiation to instantiate a member
14146 (a member function or a static member variable) of an
14147 explicitly instantiated class template. */
14149 instantiate_class_member (tree decl, int extern_p)
14151 mark_decl_instantiated (decl, extern_p);
14153 instantiate_decl (decl, /*defer_ok=*/1,
14154 /*expl_inst_class_mem_p=*/true);
14157 /* Perform an explicit instantiation of template class T. STORAGE, if
14158 non-null, is the RID for extern, inline or static. COMPLAIN is
14159 nonzero if this is called from the parser, zero if called recursively,
14160 since the standard is unclear (as detailed below). */
14163 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
14168 int previous_instantiation_extern_p = 0;
14170 if (TREE_CODE (t) == TYPE_DECL)
14173 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
14175 error ("explicit instantiation of non-template type %qT", t);
14181 if (!COMPLETE_TYPE_P (t))
14183 if (complain & tf_error)
14184 error ("explicit instantiation of %q#T before definition of template",
14189 if (storage != NULL_TREE)
14191 if (pedantic && !in_system_header)
14192 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
14195 if (storage == ridpointers[(int) RID_INLINE])
14197 else if (storage == ridpointers[(int) RID_EXTERN])
14199 else if (storage == ridpointers[(int) RID_STATIC])
14203 error ("storage class %qD applied to template instantiation",
14209 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
14211 /* DR 259 [temp.spec].
14213 Both an explicit instantiation and a declaration of an explicit
14214 specialization shall not appear in a program unless the explicit
14215 instantiation follows a declaration of the explicit specialization.
14217 For a given set of template parameters, if an explicit
14218 instantiation of a template appears after a declaration of an
14219 explicit specialization for that template, the explicit
14220 instantiation has no effect. */
14223 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
14227 No program shall explicitly instantiate any template more
14230 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
14231 instantiation was `extern'. If EXTERN_P then the second is.
14232 These cases are OK. */
14233 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
14235 if (!previous_instantiation_extern_p && !extern_p
14236 && (complain & tf_error))
14237 pedwarn ("duplicate explicit instantiation of %q#T", t);
14239 /* If we've already instantiated the template, just return now. */
14240 if (!CLASSTYPE_INTERFACE_ONLY (t))
14244 check_explicit_instantiation_namespace (TYPE_NAME (t));
14245 mark_class_instantiated (t, extern_p);
14253 /* In contrast to implicit instantiation, where only the
14254 declarations, and not the definitions, of members are
14255 instantiated, we have here:
14259 The explicit instantiation of a class template specialization
14260 implies the instantiation of all of its members not
14261 previously explicitly specialized in the translation unit
14262 containing the explicit instantiation.
14264 Of course, we can't instantiate member template classes, since
14265 we don't have any arguments for them. Note that the standard
14266 is unclear on whether the instantiation of the members are
14267 *explicit* instantiations or not. However, the most natural
14268 interpretation is that it should be an explicit instantiation. */
14271 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
14272 if (TREE_CODE (tmp) == FUNCTION_DECL
14273 && DECL_TEMPLATE_INSTANTIATION (tmp))
14274 instantiate_class_member (tmp, extern_p);
14276 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
14277 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
14278 instantiate_class_member (tmp, extern_p);
14280 if (CLASSTYPE_NESTED_UTDS (t))
14281 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
14282 bt_instantiate_type_proc, &storage);
14286 /* Given a function DECL, which is a specialization of TMPL, modify
14287 DECL to be a re-instantiation of TMPL with the same template
14288 arguments. TMPL should be the template into which tsubst'ing
14289 should occur for DECL, not the most general template.
14291 One reason for doing this is a scenario like this:
14294 void f(const T&, int i);
14296 void g() { f(3, 7); }
14299 void f(const T& t, const int i) { }
14301 Note that when the template is first instantiated, with
14302 instantiate_template, the resulting DECL will have no name for the
14303 first parameter, and the wrong type for the second. So, when we go
14304 to instantiate the DECL, we regenerate it. */
14307 regenerate_decl_from_template (tree decl, tree tmpl)
14309 /* The arguments used to instantiate DECL, from the most general
14314 args = DECL_TI_ARGS (decl);
14315 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
14317 /* Make sure that we can see identifiers, and compute access
14319 push_access_scope (decl);
14321 if (TREE_CODE (decl) == FUNCTION_DECL)
14329 args_depth = TMPL_ARGS_DEPTH (args);
14330 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
14331 if (args_depth > parms_depth)
14332 args = get_innermost_template_args (args, parms_depth);
14334 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
14335 args, tf_error, NULL_TREE);
14337 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
14340 /* Merge parameter declarations. */
14341 decl_parm = skip_artificial_parms_for (decl,
14342 DECL_ARGUMENTS (decl));
14344 = skip_artificial_parms_for (code_pattern,
14345 DECL_ARGUMENTS (code_pattern));
14346 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
14351 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
14352 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
14353 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
14355 parm_type = type_decays_to (parm_type);
14356 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
14357 TREE_TYPE (decl_parm) = parm_type;
14358 attributes = DECL_ATTRIBUTES (pattern_parm);
14359 if (DECL_ATTRIBUTES (decl_parm) != attributes)
14361 DECL_ATTRIBUTES (decl_parm) = attributes;
14362 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
14364 decl_parm = TREE_CHAIN (decl_parm);
14365 pattern_parm = TREE_CHAIN (pattern_parm);
14367 /* Merge any parameters that match with the function parameter
14369 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
14372 tree expanded_types;
14373 /* Expand the TYPE_PACK_EXPANSION that provides the types for
14374 the parameters in this function parameter pack. */
14375 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
14376 args, tf_error, NULL_TREE);
14377 len = TREE_VEC_LENGTH (expanded_types);
14378 for (i = 0; i < len; i++)
14383 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
14384 /* Rename the parameter to include the index. */
14385 DECL_NAME (decl_parm) =
14386 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
14387 parm_type = TREE_VEC_ELT (expanded_types, i);
14388 parm_type = type_decays_to (parm_type);
14389 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
14390 TREE_TYPE (decl_parm) = parm_type;
14391 attributes = DECL_ATTRIBUTES (pattern_parm);
14392 if (DECL_ATTRIBUTES (decl_parm) != attributes)
14394 DECL_ATTRIBUTES (decl_parm) = attributes;
14395 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
14397 decl_parm = TREE_CHAIN (decl_parm);
14400 /* Merge additional specifiers from the CODE_PATTERN. */
14401 if (DECL_DECLARED_INLINE_P (code_pattern)
14402 && !DECL_DECLARED_INLINE_P (decl))
14403 DECL_DECLARED_INLINE_P (decl) = 1;
14404 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
14405 DECL_INLINE (decl) = 1;
14407 else if (TREE_CODE (decl) == VAR_DECL)
14408 DECL_INITIAL (decl) =
14409 tsubst_expr (DECL_INITIAL (code_pattern), args,
14410 tf_error, DECL_TI_TEMPLATE (decl),
14411 /*integral_constant_expression_p=*/false);
14413 gcc_unreachable ();
14415 pop_access_scope (decl);
14418 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
14419 substituted to get DECL. */
14422 template_for_substitution (tree decl)
14424 tree tmpl = DECL_TI_TEMPLATE (decl);
14426 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
14427 for the instantiation. This is not always the most general
14428 template. Consider, for example:
14431 struct S { template <class U> void f();
14432 template <> void f<int>(); };
14434 and an instantiation of S<double>::f<int>. We want TD to be the
14435 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
14436 while (/* An instantiation cannot have a definition, so we need a
14437 more general template. */
14438 DECL_TEMPLATE_INSTANTIATION (tmpl)
14439 /* We must also deal with friend templates. Given:
14441 template <class T> struct S {
14442 template <class U> friend void f() {};
14445 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
14446 so far as the language is concerned, but that's still
14447 where we get the pattern for the instantiation from. On
14448 other hand, if the definition comes outside the class, say:
14450 template <class T> struct S {
14451 template <class U> friend void f();
14453 template <class U> friend void f() {}
14455 we don't need to look any further. That's what the check for
14456 DECL_INITIAL is for. */
14457 || (TREE_CODE (decl) == FUNCTION_DECL
14458 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
14459 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
14461 /* The present template, TD, should not be a definition. If it
14462 were a definition, we should be using it! Note that we
14463 cannot restructure the loop to just keep going until we find
14464 a template with a definition, since that might go too far if
14465 a specialization was declared, but not defined. */
14466 gcc_assert (TREE_CODE (decl) != VAR_DECL
14467 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
14469 /* Fetch the more general template. */
14470 tmpl = DECL_TI_TEMPLATE (tmpl);
14476 /* Produce the definition of D, a _DECL generated from a template. If
14477 DEFER_OK is nonzero, then we don't have to actually do the
14478 instantiation now; we just have to do it sometime. Normally it is
14479 an error if this is an explicit instantiation but D is undefined.
14480 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
14481 explicitly instantiated class template. */
14484 instantiate_decl (tree d, int defer_ok,
14485 bool expl_inst_class_mem_p)
14487 tree tmpl = DECL_TI_TEMPLATE (d);
14494 bool pattern_defined;
14496 location_t saved_loc = input_location;
14497 int saved_in_system_header = in_system_header;
14500 /* This function should only be used to instantiate templates for
14501 functions and static member variables. */
14502 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
14503 || TREE_CODE (d) == VAR_DECL);
14505 /* Variables are never deferred; if instantiation is required, they
14506 are instantiated right away. That allows for better code in the
14507 case that an expression refers to the value of the variable --
14508 if the variable has a constant value the referring expression can
14509 take advantage of that fact. */
14510 if (TREE_CODE (d) == VAR_DECL)
14513 /* Don't instantiate cloned functions. Instead, instantiate the
14514 functions they cloned. */
14515 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
14516 d = DECL_CLONED_FUNCTION (d);
14518 if (DECL_TEMPLATE_INSTANTIATED (d))
14519 /* D has already been instantiated. It might seem reasonable to
14520 check whether or not D is an explicit instantiation, and, if so,
14521 stop here. But when an explicit instantiation is deferred
14522 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
14523 is set, even though we still need to do the instantiation. */
14526 /* If we already have a specialization of this declaration, then
14527 there's no reason to instantiate it. Note that
14528 retrieve_specialization gives us both instantiations and
14529 specializations, so we must explicitly check
14530 DECL_TEMPLATE_SPECIALIZATION. */
14531 gen_tmpl = most_general_template (tmpl);
14532 gen_args = DECL_TI_ARGS (d);
14533 spec = retrieve_specialization (gen_tmpl, gen_args,
14534 /*class_specializations_p=*/false);
14535 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
14538 /* This needs to happen before any tsubsting. */
14539 if (! push_tinst_level (d))
14542 timevar_push (TV_PARSE);
14544 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
14545 for the instantiation. */
14546 td = template_for_substitution (d);
14547 code_pattern = DECL_TEMPLATE_RESULT (td);
14549 /* We should never be trying to instantiate a member of a class
14550 template or partial specialization. */
14551 gcc_assert (d != code_pattern);
14553 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
14554 || DECL_TEMPLATE_SPECIALIZATION (td))
14555 /* In the case of a friend template whose definition is provided
14556 outside the class, we may have too many arguments. Drop the
14557 ones we don't need. The same is true for specializations. */
14558 args = get_innermost_template_args
14559 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
14563 if (TREE_CODE (d) == FUNCTION_DECL)
14564 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
14566 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
14568 /* We may be in the middle of deferred access check. Disable it now. */
14569 push_deferring_access_checks (dk_no_deferred);
14571 /* Unless an explicit instantiation directive has already determined
14572 the linkage of D, remember that a definition is available for
14574 if (pattern_defined
14575 && !DECL_INTERFACE_KNOWN (d)
14576 && !DECL_NOT_REALLY_EXTERN (d))
14577 mark_definable (d);
14579 input_location = DECL_SOURCE_LOCATION (d);
14580 in_system_header = DECL_IN_SYSTEM_HEADER (d);
14582 /* If D is a member of an explicitly instantiated class template,
14583 and no definition is available, treat it like an implicit
14585 if (!pattern_defined && expl_inst_class_mem_p
14586 && DECL_EXPLICIT_INSTANTIATION (d))
14588 DECL_NOT_REALLY_EXTERN (d) = 0;
14589 DECL_INTERFACE_KNOWN (d) = 0;
14590 SET_DECL_IMPLICIT_INSTANTIATION (d);
14595 /* Recheck the substitutions to obtain any warning messages
14596 about ignoring cv qualifiers. */
14597 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
14598 tree type = TREE_TYPE (gen);
14600 /* Make sure that we can see identifiers, and compute access
14601 correctly. D is already the target FUNCTION_DECL with the
14603 push_access_scope (d);
14605 if (TREE_CODE (gen) == FUNCTION_DECL)
14607 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
14608 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
14610 /* Don't simply tsubst the function type, as that will give
14611 duplicate warnings about poor parameter qualifications.
14612 The function arguments are the same as the decl_arguments
14613 without the top level cv qualifiers. */
14614 type = TREE_TYPE (type);
14616 tsubst (type, gen_args, tf_warning_or_error, d);
14618 pop_access_scope (d);
14621 /* Check to see whether we know that this template will be
14622 instantiated in some other file, as with "extern template"
14624 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
14625 /* In general, we do not instantiate such templates... */
14627 /* ... but we instantiate inline functions so that we can inline
14629 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
14630 /* ... we instantiate static data members whose values are
14631 needed in integral constant expressions. */
14632 && ! (TREE_CODE (d) == VAR_DECL
14633 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
14635 /* Defer all other templates, unless we have been explicitly
14636 forbidden from doing so. */
14637 if (/* If there is no definition, we cannot instantiate the
14640 /* If it's OK to postpone instantiation, do so. */
14642 /* If this is a static data member that will be defined
14643 elsewhere, we don't want to instantiate the entire data
14644 member, but we do want to instantiate the initializer so that
14645 we can substitute that elsewhere. */
14646 || (external_p && TREE_CODE (d) == VAR_DECL))
14648 /* The definition of the static data member is now required so
14649 we must substitute the initializer. */
14650 if (TREE_CODE (d) == VAR_DECL
14651 && !DECL_INITIAL (d)
14652 && DECL_INITIAL (code_pattern))
14657 ns = decl_namespace_context (d);
14658 push_nested_namespace (ns);
14659 push_nested_class (DECL_CONTEXT (d));
14660 init = tsubst_expr (DECL_INITIAL (code_pattern),
14662 tf_warning_or_error, NULL_TREE,
14663 /*integral_constant_expression_p=*/false);
14664 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
14665 /*asmspec_tree=*/NULL_TREE,
14666 LOOKUP_ONLYCONVERTING);
14667 pop_nested_class ();
14668 pop_nested_namespace (ns);
14671 /* We restore the source position here because it's used by
14672 add_pending_template. */
14673 input_location = saved_loc;
14675 if (at_eof && !pattern_defined
14676 && DECL_EXPLICIT_INSTANTIATION (d))
14679 The definition of a non-exported function template, a
14680 non-exported member function template, or a non-exported
14681 member function or static data member of a class template
14682 shall be present in every translation unit in which it is
14683 explicitly instantiated. */
14685 ("explicit instantiation of %qD but no definition available", d);
14687 /* ??? Historically, we have instantiated inline functions, even
14688 when marked as "extern template". */
14689 if (!(external_p && TREE_CODE (d) == VAR_DECL))
14690 add_pending_template (d);
14693 /* Tell the repository that D is available in this translation unit
14694 -- and see if it is supposed to be instantiated here. */
14695 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
14697 /* In a PCH file, despite the fact that the repository hasn't
14698 requested instantiation in the PCH it is still possible that
14699 an instantiation will be required in a file that includes the
14702 add_pending_template (d);
14703 /* Instantiate inline functions so that the inliner can do its
14704 job, even though we'll not be emitting a copy of this
14706 if (!(TREE_CODE (d) == FUNCTION_DECL
14707 && flag_inline_trees
14708 && DECL_DECLARED_INLINE_P (d)))
14712 need_push = !cfun || !global_bindings_p ();
14714 push_to_top_level ();
14716 /* Mark D as instantiated so that recursive calls to
14717 instantiate_decl do not try to instantiate it again. */
14718 DECL_TEMPLATE_INSTANTIATED (d) = 1;
14720 /* Regenerate the declaration in case the template has been modified
14721 by a subsequent redeclaration. */
14722 regenerate_decl_from_template (d, td);
14724 /* We already set the file and line above. Reset them now in case
14725 they changed as a result of calling regenerate_decl_from_template. */
14726 input_location = DECL_SOURCE_LOCATION (d);
14728 if (TREE_CODE (d) == VAR_DECL)
14732 /* Clear out DECL_RTL; whatever was there before may not be right
14733 since we've reset the type of the declaration. */
14734 SET_DECL_RTL (d, NULL_RTX);
14735 DECL_IN_AGGR_P (d) = 0;
14737 /* The initializer is placed in DECL_INITIAL by
14738 regenerate_decl_from_template. Pull it out so that
14739 finish_decl can process it. */
14740 init = DECL_INITIAL (d);
14741 DECL_INITIAL (d) = NULL_TREE;
14742 DECL_INITIALIZED_P (d) = 0;
14744 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
14745 initializer. That function will defer actual emission until
14746 we have a chance to determine linkage. */
14747 DECL_EXTERNAL (d) = 0;
14749 /* Enter the scope of D so that access-checking works correctly. */
14750 push_nested_class (DECL_CONTEXT (d));
14751 finish_decl (d, init, NULL_TREE);
14752 pop_nested_class ();
14754 else if (TREE_CODE (d) == FUNCTION_DECL)
14756 htab_t saved_local_specializations;
14761 /* Save away the current list, in case we are instantiating one
14762 template from within the body of another. */
14763 saved_local_specializations = local_specializations;
14765 /* Set up the list of local specializations. */
14766 local_specializations = htab_create (37,
14767 hash_local_specialization,
14768 eq_local_specializations,
14771 /* Set up context. */
14772 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
14774 /* Create substitution entries for the parameters. */
14775 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
14776 tmpl_parm = DECL_ARGUMENTS (subst_decl);
14777 spec_parm = DECL_ARGUMENTS (d);
14778 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
14780 register_local_specialization (spec_parm, tmpl_parm);
14781 spec_parm = skip_artificial_parms_for (d, spec_parm);
14782 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
14784 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
14786 register_local_specialization (spec_parm, tmpl_parm);
14787 tmpl_parm = TREE_CHAIN (tmpl_parm);
14788 spec_parm = TREE_CHAIN (spec_parm);
14790 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
14792 /* Collect all of the extra "packed" parameters into an
14796 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
14797 tree argtypepack = make_node (TYPE_ARGUMENT_PACK);
14801 /* Count how many parameters remain. */
14802 for (t = spec_parm; t; t = TREE_CHAIN (t))
14805 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
14806 parmvec = make_tree_vec (len);
14807 parmtypevec = make_tree_vec (len);
14808 for(i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
14810 TREE_VEC_ELT (parmvec, i) = spec_parm;
14811 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
14814 /* Build the argument packs. */
14815 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
14816 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
14817 TREE_TYPE (argpack) = argtypepack;
14819 /* Register the (value) argument pack as a specialization of
14820 TMPL_PARM, then move on. */
14821 register_local_specialization (argpack, tmpl_parm);
14822 tmpl_parm = TREE_CHAIN (tmpl_parm);
14824 gcc_assert (!spec_parm);
14826 /* Substitute into the body of the function. */
14827 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
14828 tf_warning_or_error, tmpl,
14829 /*integral_constant_expression_p=*/false);
14831 /* Set the current input_location to the end of the function
14832 so that finish_function knows where we are. */
14833 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
14835 /* We don't need the local specializations any more. */
14836 htab_delete (local_specializations);
14837 local_specializations = saved_local_specializations;
14839 /* Finish the function. */
14840 d = finish_function (0);
14841 expand_or_defer_fn (d);
14844 /* We're not deferring instantiation any more. */
14845 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
14848 pop_from_top_level ();
14851 input_location = saved_loc;
14852 in_system_header = saved_in_system_header;
14853 pop_deferring_access_checks ();
14854 pop_tinst_level ();
14856 timevar_pop (TV_PARSE);
14861 /* Run through the list of templates that we wish we could
14862 instantiate, and instantiate any we can. RETRIES is the
14863 number of times we retry pending template instantiation. */
14866 instantiate_pending_templates (int retries)
14869 location_t saved_loc = input_location;
14870 int saved_in_system_header = in_system_header;
14872 /* Instantiating templates may trigger vtable generation. This in turn
14873 may require further template instantiations. We place a limit here
14874 to avoid infinite loop. */
14875 if (pending_templates && retries >= max_tinst_depth)
14877 tree decl = pending_templates->tinst->decl;
14879 error ("template instantiation depth exceeds maximum of %d"
14880 " instantiating %q+D, possibly from virtual table generation"
14881 " (use -ftemplate-depth-NN to increase the maximum)",
14882 max_tinst_depth, decl);
14883 if (TREE_CODE (decl) == FUNCTION_DECL)
14884 /* Pretend that we defined it. */
14885 DECL_INITIAL (decl) = error_mark_node;
14891 struct pending_template **t = &pending_templates;
14892 struct pending_template *last = NULL;
14896 tree instantiation = reopen_tinst_level ((*t)->tinst);
14897 bool complete = false;
14899 if (TYPE_P (instantiation))
14903 if (!COMPLETE_TYPE_P (instantiation))
14905 instantiate_class_template (instantiation);
14906 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
14907 for (fn = TYPE_METHODS (instantiation);
14909 fn = TREE_CHAIN (fn))
14910 if (! DECL_ARTIFICIAL (fn))
14911 instantiate_decl (fn,
14913 /*expl_inst_class_mem_p=*/false);
14914 if (COMPLETE_TYPE_P (instantiation))
14918 complete = COMPLETE_TYPE_P (instantiation);
14922 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
14923 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
14926 = instantiate_decl (instantiation,
14928 /*expl_inst_class_mem_p=*/false);
14929 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
14933 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
14934 || DECL_TEMPLATE_INSTANTIATED (instantiation));
14938 /* If INSTANTIATION has been instantiated, then we don't
14939 need to consider it again in the future. */
14947 current_tinst_level = NULL;
14949 last_pending_template = last;
14951 while (reconsider);
14953 input_location = saved_loc;
14954 in_system_header = saved_in_system_header;
14957 /* Substitute ARGVEC into T, which is a list of initializers for
14958 either base class or a non-static data member. The TREE_PURPOSEs
14959 are DECLs, and the TREE_VALUEs are the initializer values. Used by
14960 instantiate_decl. */
14963 tsubst_initializer_list (tree t, tree argvec)
14965 tree inits = NULL_TREE;
14967 for (; t; t = TREE_CHAIN (t))
14971 tree expanded_bases = NULL_TREE;
14972 tree expanded_arguments = NULL_TREE;
14975 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
14980 /* Expand the base class expansion type into separate base
14982 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
14983 tf_warning_or_error,
14985 if (expanded_bases == error_mark_node)
14988 /* We'll be building separate TREE_LISTs of arguments for
14990 len = TREE_VEC_LENGTH (expanded_bases);
14991 expanded_arguments = make_tree_vec (len);
14992 for (i = 0; i < len; i++)
14993 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
14995 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
14996 expand each argument in the TREE_VALUE of t. */
14997 expr = make_node (EXPR_PACK_EXPANSION);
14998 PACK_EXPANSION_PARAMETER_PACKS (expr) =
14999 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
15001 /* Substitute parameter packs into each argument in the
15003 in_base_initializer = 1;
15004 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
15006 tree expanded_exprs;
15008 /* Expand the argument. */
15009 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
15010 expanded_exprs = tsubst_pack_expansion (expr, argvec,
15011 tf_warning_or_error,
15014 /* Prepend each of the expanded expressions to the
15015 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
15016 for (i = 0; i < len; i++)
15018 TREE_VEC_ELT (expanded_arguments, i) =
15019 tree_cons (NULL_TREE, TREE_VEC_ELT (expanded_exprs, i),
15020 TREE_VEC_ELT (expanded_arguments, i));
15023 in_base_initializer = 0;
15025 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
15026 since we built them backwards. */
15027 for (i = 0; i < len; i++)
15029 TREE_VEC_ELT (expanded_arguments, i) =
15030 nreverse (TREE_VEC_ELT (expanded_arguments, i));
15034 for (i = 0; i < len; ++i)
15036 if (expanded_bases)
15038 decl = TREE_VEC_ELT (expanded_bases, i);
15039 decl = expand_member_init (decl);
15040 init = TREE_VEC_ELT (expanded_arguments, i);
15044 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
15045 tf_warning_or_error, NULL_TREE);
15047 decl = expand_member_init (decl);
15048 if (decl && !DECL_P (decl))
15049 in_base_initializer = 1;
15051 init = tsubst_expr (TREE_VALUE (t), argvec,
15052 tf_warning_or_error, NULL_TREE,
15053 /*integral_constant_expression_p=*/false);
15054 in_base_initializer = 0;
15059 init = build_tree_list (decl, init);
15060 TREE_CHAIN (init) = inits;
15068 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
15071 set_current_access_from_decl (tree decl)
15073 if (TREE_PRIVATE (decl))
15074 current_access_specifier = access_private_node;
15075 else if (TREE_PROTECTED (decl))
15076 current_access_specifier = access_protected_node;
15078 current_access_specifier = access_public_node;
15081 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
15082 is the instantiation (which should have been created with
15083 start_enum) and ARGS are the template arguments to use. */
15086 tsubst_enum (tree tag, tree newtag, tree args)
15090 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
15095 decl = TREE_VALUE (e);
15096 /* Note that in a template enum, the TREE_VALUE is the
15097 CONST_DECL, not the corresponding INTEGER_CST. */
15098 value = tsubst_expr (DECL_INITIAL (decl),
15099 args, tf_warning_or_error, NULL_TREE,
15100 /*integral_constant_expression_p=*/true);
15102 /* Give this enumeration constant the correct access. */
15103 set_current_access_from_decl (decl);
15105 /* Actually build the enumerator itself. */
15106 build_enumerator (DECL_NAME (decl), value, newtag);
15109 finish_enum (newtag);
15110 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
15111 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
15114 /* DECL is a FUNCTION_DECL that is a template specialization. Return
15115 its type -- but without substituting the innermost set of template
15116 arguments. So, innermost set of template parameters will appear in
15120 get_mostly_instantiated_function_type (tree decl)
15128 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
15129 targs = DECL_TI_ARGS (decl);
15130 tparms = DECL_TEMPLATE_PARMS (tmpl);
15131 parm_depth = TMPL_PARMS_DEPTH (tparms);
15133 /* There should be as many levels of arguments as there are levels
15135 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
15137 fn_type = TREE_TYPE (tmpl);
15139 if (parm_depth == 1)
15140 /* No substitution is necessary. */
15144 int i, save_access_control;
15147 /* Replace the innermost level of the TARGS with NULL_TREEs to
15148 let tsubst know not to substitute for those parameters. */
15149 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
15150 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
15151 SET_TMPL_ARGS_LEVEL (partial_args, i,
15152 TMPL_ARGS_LEVEL (targs, i));
15153 SET_TMPL_ARGS_LEVEL (partial_args,
15154 TMPL_ARGS_DEPTH (targs),
15155 make_tree_vec (DECL_NTPARMS (tmpl)));
15157 /* Disable access control as this function is used only during
15159 save_access_control = flag_access_control;
15160 flag_access_control = 0;
15162 ++processing_template_decl;
15163 /* Now, do the (partial) substitution to figure out the
15164 appropriate function type. */
15165 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
15166 --processing_template_decl;
15168 /* Substitute into the template parameters to obtain the real
15169 innermost set of parameters. This step is important if the
15170 innermost set of template parameters contains value
15171 parameters whose types depend on outer template parameters. */
15172 TREE_VEC_LENGTH (partial_args)--;
15173 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
15175 flag_access_control = save_access_control;
15181 /* Return truthvalue if we're processing a template different from
15182 the last one involved in diagnostics. */
15184 problematic_instantiation_changed (void)
15186 return last_template_error_tick != tinst_level_tick;
15189 /* Remember current template involved in diagnostics. */
15191 record_last_problematic_instantiation (void)
15193 last_template_error_tick = tinst_level_tick;
15196 struct tinst_level *
15197 current_instantiation (void)
15199 return current_tinst_level;
15202 /* [temp.param] Check that template non-type parm TYPE is of an allowable
15203 type. Return zero for ok, nonzero for disallowed. Issue error and
15204 warning messages under control of COMPLAIN. */
15207 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
15209 if (INTEGRAL_TYPE_P (type))
15211 else if (POINTER_TYPE_P (type))
15213 else if (TYPE_PTR_TO_MEMBER_P (type))
15215 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
15217 else if (TREE_CODE (type) == TYPENAME_TYPE)
15220 if (complain & tf_error)
15221 error ("%q#T is not a valid type for a template constant parameter", type);
15225 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
15226 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
15229 dependent_type_p_r (tree type)
15235 A type is dependent if it is:
15237 -- a template parameter. Template template parameters are types
15238 for us (since TYPE_P holds true for them) so we handle
15240 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
15241 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
15243 /* -- a qualified-id with a nested-name-specifier which contains a
15244 class-name that names a dependent type or whose unqualified-id
15245 names a dependent type. */
15246 if (TREE_CODE (type) == TYPENAME_TYPE)
15248 /* -- a cv-qualified type where the cv-unqualified type is
15250 type = TYPE_MAIN_VARIANT (type);
15251 /* -- a compound type constructed from any dependent type. */
15252 if (TYPE_PTR_TO_MEMBER_P (type))
15253 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
15254 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
15256 else if (TREE_CODE (type) == POINTER_TYPE
15257 || TREE_CODE (type) == REFERENCE_TYPE)
15258 return dependent_type_p (TREE_TYPE (type));
15259 else if (TREE_CODE (type) == FUNCTION_TYPE
15260 || TREE_CODE (type) == METHOD_TYPE)
15264 if (dependent_type_p (TREE_TYPE (type)))
15266 for (arg_type = TYPE_ARG_TYPES (type);
15268 arg_type = TREE_CHAIN (arg_type))
15269 if (dependent_type_p (TREE_VALUE (arg_type)))
15273 /* -- an array type constructed from any dependent type or whose
15274 size is specified by a constant expression that is
15275 value-dependent. */
15276 if (TREE_CODE (type) == ARRAY_TYPE)
15278 if (TYPE_DOMAIN (type)
15279 && ((value_dependent_expression_p
15280 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
15281 || (type_dependent_expression_p
15282 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
15284 return dependent_type_p (TREE_TYPE (type));
15287 /* -- a template-id in which either the template name is a template
15289 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
15291 /* ... or any of the template arguments is a dependent type or
15292 an expression that is type-dependent or value-dependent. */
15293 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
15294 && (any_dependent_template_arguments_p
15295 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
15298 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
15299 argument of the `typeof' expression is not type-dependent, then
15300 it should already been have resolved. */
15301 if (TREE_CODE (type) == TYPEOF_TYPE
15302 || TREE_CODE (type) == DECLTYPE_TYPE)
15305 /* A template argument pack is dependent if any of its packed
15307 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
15309 tree args = ARGUMENT_PACK_ARGS (type);
15310 int i, len = TREE_VEC_LENGTH (args);
15311 for (i = 0; i < len; ++i)
15312 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
15316 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
15317 be template parameters. */
15318 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
15321 /* The standard does not specifically mention types that are local
15322 to template functions or local classes, but they should be
15323 considered dependent too. For example:
15325 template <int I> void f() {
15330 The size of `E' cannot be known until the value of `I' has been
15331 determined. Therefore, `E' must be considered dependent. */
15332 scope = TYPE_CONTEXT (type);
15333 if (scope && TYPE_P (scope))
15334 return dependent_type_p (scope);
15335 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
15336 return type_dependent_expression_p (scope);
15338 /* Other types are non-dependent. */
15342 /* Returns TRUE if TYPE is dependent, in the sense of
15343 [temp.dep.type]. */
15346 dependent_type_p (tree type)
15348 /* If there are no template parameters in scope, then there can't be
15349 any dependent types. */
15350 if (!processing_template_decl)
15352 /* If we are not processing a template, then nobody should be
15353 providing us with a dependent type. */
15355 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM);
15359 /* If the type is NULL, we have not computed a type for the entity
15360 in question; in that case, the type is dependent. */
15364 /* Erroneous types can be considered non-dependent. */
15365 if (type == error_mark_node)
15368 /* If we have not already computed the appropriate value for TYPE,
15370 if (!TYPE_DEPENDENT_P_VALID (type))
15372 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
15373 TYPE_DEPENDENT_P_VALID (type) = 1;
15376 return TYPE_DEPENDENT_P (type);
15379 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
15382 dependent_scope_ref_p (tree expression, bool criterion (tree))
15387 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
15389 if (!TYPE_P (TREE_OPERAND (expression, 0)))
15392 scope = TREE_OPERAND (expression, 0);
15393 name = TREE_OPERAND (expression, 1);
15397 An id-expression is type-dependent if it contains a
15398 nested-name-specifier that contains a class-name that names a
15400 /* The suggested resolution to Core Issue 2 implies that if the
15401 qualifying type is the current class, then we must peek
15404 && currently_open_class (scope)
15405 && !criterion (name))
15407 if (dependent_type_p (scope))
15413 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
15414 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
15418 value_dependent_expression_p (tree expression)
15420 if (!processing_template_decl)
15423 /* A name declared with a dependent type. */
15424 if (DECL_P (expression) && type_dependent_expression_p (expression))
15427 switch (TREE_CODE (expression))
15429 case IDENTIFIER_NODE:
15430 /* A name that has not been looked up -- must be dependent. */
15433 case TEMPLATE_PARM_INDEX:
15434 /* A non-type template parm. */
15438 /* A non-type template parm. */
15439 if (DECL_TEMPLATE_PARM_P (expression))
15444 /* A constant with integral or enumeration type and is initialized
15445 with an expression that is value-dependent. */
15446 if (DECL_INITIAL (expression)
15447 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
15448 && value_dependent_expression_p (DECL_INITIAL (expression)))
15452 case DYNAMIC_CAST_EXPR:
15453 case STATIC_CAST_EXPR:
15454 case CONST_CAST_EXPR:
15455 case REINTERPRET_CAST_EXPR:
15457 /* These expressions are value-dependent if the type to which
15458 the cast occurs is dependent or the expression being casted
15459 is value-dependent. */
15461 tree type = TREE_TYPE (expression);
15463 if (dependent_type_p (type))
15466 /* A functional cast has a list of operands. */
15467 expression = TREE_OPERAND (expression, 0);
15470 /* If there are no operands, it must be an expression such
15471 as "int()". This should not happen for aggregate types
15472 because it would form non-constant expressions. */
15473 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
15478 if (TREE_CODE (expression) == TREE_LIST)
15479 return any_value_dependent_elements_p (expression);
15481 return value_dependent_expression_p (expression);
15486 /* A `sizeof' expression is value-dependent if the operand is
15487 type-dependent or is a pack expansion. */
15488 expression = TREE_OPERAND (expression, 0);
15489 if (PACK_EXPANSION_P (expression))
15491 else if (TYPE_P (expression))
15492 return dependent_type_p (expression);
15493 return type_dependent_expression_p (expression);
15496 return dependent_scope_ref_p (expression, value_dependent_expression_p);
15498 case COMPONENT_REF:
15499 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
15500 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
15503 /* A CALL_EXPR may appear in a constant expression if it is a
15504 call to a builtin function, e.g., __builtin_constant_p. All
15505 such calls are value-dependent. */
15508 case NONTYPE_ARGUMENT_PACK:
15509 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
15510 is value-dependent. */
15512 tree values = ARGUMENT_PACK_ARGS (expression);
15513 int i, len = TREE_VEC_LENGTH (values);
15515 for (i = 0; i < len; ++i)
15516 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
15524 tree type2 = TRAIT_EXPR_TYPE2 (expression);
15525 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
15526 || (type2 ? dependent_type_p (type2) : false));
15530 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
15531 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
15534 /* A constant expression is value-dependent if any subexpression is
15535 value-dependent. */
15536 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
15538 case tcc_reference:
15540 return (value_dependent_expression_p
15541 (TREE_OPERAND (expression, 0)));
15543 case tcc_comparison:
15545 return ((value_dependent_expression_p
15546 (TREE_OPERAND (expression, 0)))
15547 || (value_dependent_expression_p
15548 (TREE_OPERAND (expression, 1))));
15550 case tcc_expression:
15554 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
15555 /* In some cases, some of the operands may be missing.
15556 (For example, in the case of PREDECREMENT_EXPR, the
15557 amount to increment by may be missing.) That doesn't
15558 make the expression dependent. */
15559 if (TREE_OPERAND (expression, i)
15560 && (value_dependent_expression_p
15561 (TREE_OPERAND (expression, i))))
15571 /* The expression is not value-dependent. */
15575 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
15576 [temp.dep.expr]. */
15579 type_dependent_expression_p (tree expression)
15581 if (!processing_template_decl)
15584 if (expression == error_mark_node)
15587 /* An unresolved name is always dependent. */
15588 if (TREE_CODE (expression) == IDENTIFIER_NODE
15589 || TREE_CODE (expression) == USING_DECL)
15592 /* Some expression forms are never type-dependent. */
15593 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
15594 || TREE_CODE (expression) == SIZEOF_EXPR
15595 || TREE_CODE (expression) == ALIGNOF_EXPR
15596 || TREE_CODE (expression) == TRAIT_EXPR
15597 || TREE_CODE (expression) == TYPEID_EXPR
15598 || TREE_CODE (expression) == DELETE_EXPR
15599 || TREE_CODE (expression) == VEC_DELETE_EXPR
15600 || TREE_CODE (expression) == THROW_EXPR)
15603 /* The types of these expressions depends only on the type to which
15604 the cast occurs. */
15605 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
15606 || TREE_CODE (expression) == STATIC_CAST_EXPR
15607 || TREE_CODE (expression) == CONST_CAST_EXPR
15608 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
15609 || TREE_CODE (expression) == CAST_EXPR)
15610 return dependent_type_p (TREE_TYPE (expression));
15612 /* The types of these expressions depends only on the type created
15613 by the expression. */
15614 if (TREE_CODE (expression) == NEW_EXPR
15615 || TREE_CODE (expression) == VEC_NEW_EXPR)
15617 /* For NEW_EXPR tree nodes created inside a template, either
15618 the object type itself or a TREE_LIST may appear as the
15620 tree type = TREE_OPERAND (expression, 1);
15621 if (TREE_CODE (type) == TREE_LIST)
15622 /* This is an array type. We need to check array dimensions
15624 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
15625 || value_dependent_expression_p
15626 (TREE_OPERAND (TREE_VALUE (type), 1));
15628 return dependent_type_p (type);
15631 if (TREE_CODE (expression) == SCOPE_REF
15632 && dependent_scope_ref_p (expression,
15633 type_dependent_expression_p))
15636 if (TREE_CODE (expression) == FUNCTION_DECL
15637 && DECL_LANG_SPECIFIC (expression)
15638 && DECL_TEMPLATE_INFO (expression)
15639 && (any_dependent_template_arguments_p
15640 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
15643 if (TREE_CODE (expression) == TEMPLATE_DECL
15644 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
15647 if (TREE_CODE (expression) == STMT_EXPR)
15648 expression = stmt_expr_value_expr (expression);
15650 if (TREE_TYPE (expression) == unknown_type_node)
15652 if (TREE_CODE (expression) == ADDR_EXPR)
15653 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
15654 if (TREE_CODE (expression) == COMPONENT_REF
15655 || TREE_CODE (expression) == OFFSET_REF)
15657 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
15659 expression = TREE_OPERAND (expression, 1);
15660 if (TREE_CODE (expression) == IDENTIFIER_NODE)
15663 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
15664 if (TREE_CODE (expression) == SCOPE_REF)
15667 if (TREE_CODE (expression) == BASELINK)
15668 expression = BASELINK_FUNCTIONS (expression);
15670 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
15672 if (any_dependent_template_arguments_p
15673 (TREE_OPERAND (expression, 1)))
15675 expression = TREE_OPERAND (expression, 0);
15677 gcc_assert (TREE_CODE (expression) == OVERLOAD
15678 || TREE_CODE (expression) == FUNCTION_DECL);
15682 if (type_dependent_expression_p (OVL_CURRENT (expression)))
15684 expression = OVL_NEXT (expression);
15689 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
15691 return (dependent_type_p (TREE_TYPE (expression)));
15694 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
15695 contains a type-dependent expression. */
15698 any_type_dependent_arguments_p (const_tree args)
15702 tree arg = TREE_VALUE (args);
15704 if (type_dependent_expression_p (arg))
15706 args = TREE_CHAIN (args);
15711 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
15712 expressions) contains any value-dependent expressions. */
15715 any_value_dependent_elements_p (const_tree list)
15717 for (; list; list = TREE_CHAIN (list))
15718 if (value_dependent_expression_p (TREE_VALUE (list)))
15724 /* Returns TRUE if the ARG (a template argument) is dependent. */
15727 dependent_template_arg_p (tree arg)
15729 if (!processing_template_decl)
15732 if (TREE_CODE (arg) == TEMPLATE_DECL
15733 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
15734 return dependent_template_p (arg);
15735 else if (ARGUMENT_PACK_P (arg))
15737 tree args = ARGUMENT_PACK_ARGS (arg);
15738 int i, len = TREE_VEC_LENGTH (args);
15739 for (i = 0; i < len; ++i)
15741 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
15747 else if (TYPE_P (arg))
15748 return dependent_type_p (arg);
15750 return (type_dependent_expression_p (arg)
15751 || value_dependent_expression_p (arg));
15754 /* Returns true if ARGS (a collection of template arguments) contains
15755 any types that require structural equality testing. */
15758 any_template_arguments_need_structural_equality_p (tree args)
15765 if (args == error_mark_node)
15768 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
15770 tree level = TMPL_ARGS_LEVEL (args, i + 1);
15771 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
15773 tree arg = TREE_VEC_ELT (level, j);
15774 tree packed_args = NULL_TREE;
15777 if (ARGUMENT_PACK_P (arg))
15779 /* Look inside the argument pack. */
15780 packed_args = ARGUMENT_PACK_ARGS (arg);
15781 len = TREE_VEC_LENGTH (packed_args);
15784 for (k = 0; k < len; ++k)
15787 arg = TREE_VEC_ELT (packed_args, k);
15789 if (error_operand_p (arg))
15791 else if (TREE_CODE (arg) == TEMPLATE_DECL
15792 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
15794 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
15796 else if (!TYPE_P (arg) && TREE_TYPE (arg)
15797 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
15806 /* Returns true if ARGS (a collection of template arguments) contains
15807 any dependent arguments. */
15810 any_dependent_template_arguments_p (const_tree args)
15817 if (args == error_mark_node)
15820 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
15822 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
15823 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
15824 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
15831 /* Returns TRUE if the template TMPL is dependent. */
15834 dependent_template_p (tree tmpl)
15836 if (TREE_CODE (tmpl) == OVERLOAD)
15840 if (dependent_template_p (OVL_FUNCTION (tmpl)))
15842 tmpl = OVL_CHAIN (tmpl);
15847 /* Template template parameters are dependent. */
15848 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
15849 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
15851 /* So are names that have not been looked up. */
15852 if (TREE_CODE (tmpl) == SCOPE_REF
15853 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
15855 /* So are member templates of dependent classes. */
15856 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
15857 return dependent_type_p (DECL_CONTEXT (tmpl));
15861 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
15864 dependent_template_id_p (tree tmpl, tree args)
15866 return (dependent_template_p (tmpl)
15867 || any_dependent_template_arguments_p (args));
15870 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
15871 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
15872 no such TYPE can be found. Note that this function peers inside
15873 uninstantiated templates and therefore should be used only in
15874 extremely limited situations. ONLY_CURRENT_P restricts this
15875 peering to the currently open classes hierarchy (which is required
15876 when comparing types). */
15879 resolve_typename_type (tree type, bool only_current_p)
15888 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
15890 scope = TYPE_CONTEXT (type);
15891 name = TYPE_IDENTIFIER (type);
15893 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
15894 it first before we can figure out what NAME refers to. */
15895 if (TREE_CODE (scope) == TYPENAME_TYPE)
15896 scope = resolve_typename_type (scope, only_current_p);
15897 /* If we don't know what SCOPE refers to, then we cannot resolve the
15899 if (TREE_CODE (scope) == TYPENAME_TYPE)
15901 /* If the SCOPE is a template type parameter, we have no way of
15902 resolving the name. */
15903 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
15905 /* If the SCOPE is not the current instantiation, there's no reason
15906 to look inside it. */
15907 if (only_current_p && !currently_open_class (scope))
15909 /* If SCOPE isn't the template itself, it will not have a valid
15910 TYPE_FIELDS list. */
15911 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
15912 /* scope is either the template itself or a compatible instantiation
15913 like X<T>, so look up the name in the original template. */
15914 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
15916 /* scope is a partial instantiation, so we can't do the lookup or we
15917 will lose the template arguments. */
15919 /* Enter the SCOPE so that name lookup will be resolved as if we
15920 were in the class definition. In particular, SCOPE will no
15921 longer be considered a dependent type. */
15922 pushed_scope = push_scope (scope);
15923 /* Look up the declaration. */
15924 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
15926 result = NULL_TREE;
15928 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
15929 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
15932 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
15933 && TREE_CODE (decl) == TYPE_DECL)
15935 result = TREE_TYPE (decl);
15936 if (result == error_mark_node)
15937 result = NULL_TREE;
15939 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
15940 && DECL_CLASS_TEMPLATE_P (decl))
15944 /* Obtain the template and the arguments. */
15945 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
15946 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
15947 /* Instantiate the template. */
15948 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
15949 /*entering_scope=*/0,
15950 tf_error | tf_user);
15951 if (result == error_mark_node)
15952 result = NULL_TREE;
15955 /* Leave the SCOPE. */
15957 pop_scope (pushed_scope);
15959 /* If we failed to resolve it, return the original typename. */
15963 /* If lookup found a typename type, resolve that too. */
15964 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
15966 /* Ill-formed programs can cause infinite recursion here, so we
15967 must catch that. */
15968 TYPENAME_IS_RESOLVING_P (type) = 1;
15969 result = resolve_typename_type (result, only_current_p);
15970 TYPENAME_IS_RESOLVING_P (type) = 0;
15973 /* Qualify the resulting type. */
15974 quals = cp_type_quals (type);
15976 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
15981 /* EXPR is an expression which is not type-dependent. Return a proxy
15982 for EXPR that can be used to compute the types of larger
15983 expressions containing EXPR. */
15986 build_non_dependent_expr (tree expr)
15990 /* Preserve null pointer constants so that the type of things like
15991 "p == 0" where "p" is a pointer can be determined. */
15992 if (null_ptr_cst_p (expr))
15994 /* Preserve OVERLOADs; the functions must be available to resolve
15997 if (TREE_CODE (inner_expr) == STMT_EXPR)
15998 inner_expr = stmt_expr_value_expr (inner_expr);
15999 if (TREE_CODE (inner_expr) == ADDR_EXPR)
16000 inner_expr = TREE_OPERAND (inner_expr, 0);
16001 if (TREE_CODE (inner_expr) == COMPONENT_REF)
16002 inner_expr = TREE_OPERAND (inner_expr, 1);
16003 if (is_overloaded_fn (inner_expr)
16004 || TREE_CODE (inner_expr) == OFFSET_REF)
16006 /* There is no need to return a proxy for a variable. */
16007 if (TREE_CODE (expr) == VAR_DECL)
16009 /* Preserve string constants; conversions from string constants to
16010 "char *" are allowed, even though normally a "const char *"
16011 cannot be used to initialize a "char *". */
16012 if (TREE_CODE (expr) == STRING_CST)
16014 /* Preserve arithmetic constants, as an optimization -- there is no
16015 reason to create a new node. */
16016 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
16018 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
16019 There is at least one place where we want to know that a
16020 particular expression is a throw-expression: when checking a ?:
16021 expression, there are special rules if the second or third
16022 argument is a throw-expression. */
16023 if (TREE_CODE (expr) == THROW_EXPR)
16026 if (TREE_CODE (expr) == COND_EXPR)
16027 return build3 (COND_EXPR,
16029 TREE_OPERAND (expr, 0),
16030 (TREE_OPERAND (expr, 1)
16031 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
16032 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
16033 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
16034 if (TREE_CODE (expr) == COMPOUND_EXPR
16035 && !COMPOUND_EXPR_OVERLOADED (expr))
16036 return build2 (COMPOUND_EXPR,
16038 TREE_OPERAND (expr, 0),
16039 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
16041 /* If the type is unknown, it can't really be non-dependent */
16042 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
16044 /* Otherwise, build a NON_DEPENDENT_EXPR.
16046 REFERENCE_TYPEs are not stripped for expressions in templates
16047 because doing so would play havoc with mangling. Consider, for
16050 template <typename T> void f<T& g>() { g(); }
16052 In the body of "f", the expression for "g" will have
16053 REFERENCE_TYPE, even though the standard says that it should
16054 not. The reason is that we must preserve the syntactic form of
16055 the expression so that mangling (say) "f<g>" inside the body of
16056 "f" works out correctly. Therefore, the REFERENCE_TYPE is
16058 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
16061 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
16062 Return a new TREE_LIST with the various arguments replaced with
16063 equivalent non-dependent expressions. */
16066 build_non_dependent_args (tree args)
16071 new_args = NULL_TREE;
16072 for (a = args; a; a = TREE_CHAIN (a))
16073 new_args = tree_cons (NULL_TREE,
16074 build_non_dependent_expr (TREE_VALUE (a)),
16076 return nreverse (new_args);
16079 #include "gt-cp-pt.h"