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_pack_r. */
2423 struct find_parameter_pack_data
2425 tree* parameter_packs;
2426 struct pointer_set_t *visited;
2429 /* Identifies all of the argument packs that occur in a template
2430 argument and appends them to the TREE_LIST inside DATA, which is a
2431 find_parameter_pack_data structure. This is a subroutine of
2432 make_pack_expansion and uses_parameter_packs. */
2434 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2437 struct find_parameter_pack_data* ppd =
2438 (struct find_parameter_pack_data*)data;
2442 tree context = TYPE_CONTEXT (t);
2443 cp_walk_tree (&context, &find_parameter_packs_r, ppd, ppd->visited);
2446 /* This switch statement will return immediately if we don't find a
2448 switch (TREE_CODE (t))
2450 case TEMPLATE_PARM_INDEX:
2451 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2455 case BOUND_TEMPLATE_TEMPLATE_PARM:
2456 /* Check the template arguments. */
2457 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2460 /* Dig out the underlying TEMPLATE_TEMPLATE_PARM. */
2461 t = TYPE_TI_TEMPLATE (t);
2462 if (DECL_P (t) && TREE_TYPE (t))
2468 case TEMPLATE_TYPE_PARM:
2469 case TEMPLATE_TEMPLATE_PARM:
2470 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2475 if (FUNCTION_PARAMETER_PACK_P (t))
2477 /* We don't want to walk into the type of a PARM_DECL,
2478 because we don't want to see the type parameter pack.*/
2485 if (TYPE_PTRMEMFUNC_P (t))
2491 if (TYPE_TEMPLATE_INFO (t))
2493 tree args = TREE_VALUE (TYPE_TEMPLATE_INFO (t));
2494 cp_walk_tree (&args, &find_parameter_packs_r, ppd, ppd->visited);
2501 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
2502 && TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (t)))
2509 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
2515 case TYPE_PACK_EXPANSION:
2516 case EXPR_PACK_EXPANSION:
2521 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
2530 /* Add this parameter pack to the list. */
2531 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2536 /* Determines if the expression or type T uses any parameter packs. */
2538 uses_parameter_packs (tree t)
2540 tree parameter_packs = NULL_TREE;
2541 struct find_parameter_pack_data ppd;
2542 ppd.parameter_packs = ¶meter_packs;
2543 ppd.visited = pointer_set_create ();
2544 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2545 pointer_set_destroy (ppd.visited);
2546 return parameter_packs != NULL_TREE;
2549 /* Turn ARG, which may be an expression, type, or a TREE_LIST
2550 representation a base-class initializer into a parameter pack
2551 expansion. If all goes well, the resulting node will be an
2552 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
2555 make_pack_expansion (tree arg)
2558 tree parameter_packs = NULL_TREE;
2559 bool for_types = false;
2560 struct find_parameter_pack_data ppd;
2562 if (!arg || arg == error_mark_node)
2565 if (TREE_CODE (arg) == TREE_LIST)
2567 /* The only time we will see a TREE_LIST here is for a base
2568 class initializer. In this case, the TREE_PURPOSE will be a
2569 _TYPE node (representing the base class expansion we're
2570 initializing) and the TREE_VALUE will be a TREE_LIST
2571 containing the initialization arguments.
2573 The resulting expansion looks somewhat different from most
2574 expansions. Rather than returning just one _EXPANSION, we
2575 return a TREE_LIST whose TREE_PURPOSE is a
2576 TYPE_PACK_EXPANSION containing the bases that will be
2577 initialized. The TREE_VALUE will be identical to the
2578 original TREE_VALUE, which is a list of arguments that will
2579 be passed to each base. We do not introduce any new pack
2580 expansion nodes into the TREE_VALUE (although it is possible
2581 that some already exist), because the TREE_PURPOSE and
2582 TREE_VALUE all need to be expanded together with the same
2583 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
2584 resulting TREE_PURPOSE will mention the parameter packs in
2585 both the bases and the arguments to the bases. */
2588 tree parameter_packs = NULL_TREE;
2590 /* Determine which parameter packs will be used by the base
2592 ppd.visited = pointer_set_create ();
2593 ppd.parameter_packs = ¶meter_packs;
2594 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
2597 if (parameter_packs == NULL_TREE)
2599 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
2600 pointer_set_destroy (ppd.visited);
2601 return error_mark_node;
2604 if (TREE_VALUE (arg) != void_type_node)
2606 /* Collect the sets of parameter packs used in each of the
2607 initialization arguments. */
2608 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
2610 /* Determine which parameter packs will be expanded in this
2612 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
2617 pointer_set_destroy (ppd.visited);
2619 /* Create the pack expansion type for the base type. */
2620 purpose = make_node (TYPE_PACK_EXPANSION);
2621 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
2622 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
2624 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2625 they will rarely be compared to anything. */
2626 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
2628 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
2631 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
2634 /* Build the PACK_EXPANSION_* node. */
2635 result = make_node (for_types ? TYPE_PACK_EXPANSION : EXPR_PACK_EXPANSION);
2636 SET_PACK_EXPANSION_PATTERN (result, arg);
2637 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
2639 /* Propagate type and const-expression information. */
2640 TREE_TYPE (result) = TREE_TYPE (arg);
2641 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
2644 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2645 they will rarely be compared to anything. */
2646 SET_TYPE_STRUCTURAL_EQUALITY (result);
2648 /* Determine which parameter packs will be expanded. */
2649 ppd.parameter_packs = ¶meter_packs;
2650 ppd.visited = pointer_set_create ();
2651 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
2652 pointer_set_destroy (ppd.visited);
2654 /* Make sure we found some parameter packs. */
2655 if (parameter_packs == NULL_TREE)
2658 error ("expansion pattern %<%T%> contains no argument packs", arg);
2660 error ("expansion pattern %<%E%> contains no argument packs", arg);
2661 return error_mark_node;
2663 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
2668 /* Checks T for any "bare" parameter packs, which have not yet been
2669 expanded, and issues an error if any are found. This operation can
2670 only be done on full expressions or types (e.g., an expression
2671 statement, "if" condition, etc.), because we could have expressions like:
2673 foo(f(g(h(args)))...)
2675 where "args" is a parameter pack. check_for_bare_parameter_packs
2676 should not be called for the subexpressions args, h(args),
2677 g(h(args)), or f(g(h(args))), because we would produce erroneous
2680 Returns TRUE if there were no bare parameter packs, returns FALSE
2681 (and emits an error) if there were bare parameter packs.*/
2683 check_for_bare_parameter_packs (tree t)
2685 tree parameter_packs = NULL_TREE;
2686 struct find_parameter_pack_data ppd;
2688 if (!processing_template_decl || !t || t == error_mark_node)
2691 if (TREE_CODE (t) == TYPE_DECL)
2694 ppd.parameter_packs = ¶meter_packs;
2695 ppd.visited = pointer_set_create ();
2696 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2697 pointer_set_destroy (ppd.visited);
2699 if (parameter_packs)
2701 error ("parameter packs not expanded with `...':");
2702 while (parameter_packs)
2704 tree pack = TREE_VALUE (parameter_packs);
2705 tree name = NULL_TREE;
2707 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
2708 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
2709 name = TYPE_NAME (pack);
2710 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
2711 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
2713 name = DECL_NAME (pack);
2714 inform (" %qD", name);
2716 parameter_packs = TREE_CHAIN (parameter_packs);
2725 /* Expand any parameter packs that occur in the template arguments in
2728 expand_template_argument_pack (tree args)
2730 tree result_args = NULL_TREE;
2731 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
2732 int num_result_args = -1;
2734 /* First, determine if we need to expand anything, and the number of
2735 slots we'll need. */
2736 for (in_arg = 0; in_arg < nargs; ++in_arg)
2738 tree arg = TREE_VEC_ELT (args, in_arg);
2739 if (ARGUMENT_PACK_P (arg))
2741 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
2742 if (num_result_args < 0)
2743 num_result_args = in_arg + num_packed;
2745 num_result_args += num_packed;
2749 if (num_result_args >= 0)
2754 /* If no expansion is necessary, we're done. */
2755 if (num_result_args < 0)
2758 /* Expand arguments. */
2759 result_args = make_tree_vec (num_result_args);
2760 for (in_arg = 0; in_arg < nargs; ++in_arg)
2762 tree arg = TREE_VEC_ELT (args, in_arg);
2763 if (ARGUMENT_PACK_P (arg))
2765 tree packed = ARGUMENT_PACK_ARGS (arg);
2766 int i, num_packed = TREE_VEC_LENGTH (packed);
2767 for (i = 0; i < num_packed; ++i, ++out_arg)
2768 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
2772 TREE_VEC_ELT (result_args, out_arg) = arg;
2780 /* Complain if DECL shadows a template parameter.
2782 [temp.local]: A template-parameter shall not be redeclared within its
2783 scope (including nested scopes). */
2786 check_template_shadow (tree decl)
2790 /* If we're not in a template, we can't possibly shadow a template
2792 if (!current_template_parms)
2795 /* Figure out what we're shadowing. */
2796 if (TREE_CODE (decl) == OVERLOAD)
2797 decl = OVL_CURRENT (decl);
2798 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2800 /* If there's no previous binding for this name, we're not shadowing
2801 anything, let alone a template parameter. */
2805 /* If we're not shadowing a template parameter, we're done. Note
2806 that OLDDECL might be an OVERLOAD (or perhaps even an
2807 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2809 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2812 /* We check for decl != olddecl to avoid bogus errors for using a
2813 name inside a class. We check TPFI to avoid duplicate errors for
2814 inline member templates. */
2816 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2819 error ("declaration of %q+#D", decl);
2820 error (" shadows template parm %q+#D", olddecl);
2823 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2824 ORIG_LEVEL, DECL, and TYPE. */
2827 build_template_parm_index (int index,
2833 tree t = make_node (TEMPLATE_PARM_INDEX);
2834 TEMPLATE_PARM_IDX (t) = index;
2835 TEMPLATE_PARM_LEVEL (t) = level;
2836 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2837 TEMPLATE_PARM_DECL (t) = decl;
2838 TREE_TYPE (t) = type;
2839 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2840 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2841 TREE_READONLY (t) = TREE_READONLY (decl);
2846 /* Find the canonical type parameter for the given template type
2847 parameter. Returns the canonical type parameter, which may be TYPE
2848 if no such parameter existed. */
2850 canonical_type_parameter (tree type)
2853 int idx = TEMPLATE_TYPE_IDX (type);
2854 if (!canonical_template_parms)
2855 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
2857 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
2858 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
2860 list = VEC_index (tree, canonical_template_parms, idx);
2861 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
2862 list = TREE_CHAIN (list);
2865 return TREE_VALUE (list);
2868 VEC_replace(tree, canonical_template_parms, idx,
2869 tree_cons (NULL_TREE, type,
2870 VEC_index (tree, canonical_template_parms, idx)));
2875 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2876 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2877 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2878 new one is created. */
2881 reduce_template_parm_level (tree index, tree type, int levels, tree args,
2882 tsubst_flags_t complain)
2884 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2885 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2886 != TEMPLATE_PARM_LEVEL (index) - levels))
2888 tree orig_decl = TEMPLATE_PARM_DECL (index);
2891 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2892 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2893 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2894 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2895 DECL_ARTIFICIAL (decl) = 1;
2896 SET_DECL_TEMPLATE_PARM_P (decl);
2898 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2899 TEMPLATE_PARM_LEVEL (index) - levels,
2900 TEMPLATE_PARM_ORIG_LEVEL (index),
2902 TEMPLATE_PARM_DESCENDANTS (index) = t;
2903 TEMPLATE_PARM_PARAMETER_PACK (t)
2904 = TEMPLATE_PARM_PARAMETER_PACK (index);
2906 /* Template template parameters need this. */
2907 if (TREE_CODE (decl) == TEMPLATE_DECL)
2908 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
2909 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
2913 return TEMPLATE_PARM_DESCENDANTS (index);
2916 /* Process information from new template parameter PARM and append it to the
2917 LIST being built. This new parameter is a non-type parameter iff
2918 IS_NON_TYPE is true. This new parameter is a parameter
2919 pack iff IS_PARAMETER_PACK is true. */
2922 process_template_parm (tree list, tree parm, bool is_non_type,
2923 bool is_parameter_pack)
2930 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2931 defval = TREE_PURPOSE (parm);
2935 tree p = tree_last (list);
2937 if (p && TREE_VALUE (p) != error_mark_node)
2940 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2941 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2943 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2953 parm = TREE_VALUE (parm);
2955 SET_DECL_TEMPLATE_PARM_P (parm);
2957 if (TREE_TYPE (parm) == error_mark_node)
2959 err_parm_list = build_tree_list (defval, parm);
2960 TREE_VALUE (err_parm_list) = error_mark_node;
2961 return chainon (list, err_parm_list);
2967 The top-level cv-qualifiers on the template-parameter are
2968 ignored when determining its type. */
2969 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2970 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2972 err_parm_list = build_tree_list (defval, parm);
2973 TREE_VALUE (err_parm_list) = error_mark_node;
2974 return chainon (list, err_parm_list);
2977 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
2979 /* This template parameter is not a parameter pack, but it
2980 should be. Complain about "bare" parameter packs. */
2981 check_for_bare_parameter_packs (TREE_TYPE (parm));
2983 /* Recover by calling this a parameter pack. */
2984 is_parameter_pack = true;
2988 /* A template parameter is not modifiable. */
2989 TREE_CONSTANT (parm) = 1;
2990 TREE_INVARIANT (parm) = 1;
2991 TREE_READONLY (parm) = 1;
2992 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2993 TREE_CONSTANT (decl) = 1;
2994 TREE_INVARIANT (decl) = 1;
2995 TREE_READONLY (decl) = 1;
2996 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2997 = build_template_parm_index (idx, processing_template_decl,
2998 processing_template_decl,
2999 decl, TREE_TYPE (parm));
3001 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3002 = is_parameter_pack;
3007 parm = TREE_VALUE (TREE_VALUE (parm));
3009 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3011 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
3012 /* This is for distinguishing between real templates and template
3013 template parameters */
3014 TREE_TYPE (parm) = t;
3015 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3020 t = make_aggr_type (TEMPLATE_TYPE_PARM);
3021 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3022 decl = build_decl (TYPE_DECL, parm, t);
3025 TYPE_NAME (t) = decl;
3026 TYPE_STUB_DECL (t) = decl;
3028 TEMPLATE_TYPE_PARM_INDEX (t)
3029 = build_template_parm_index (idx, processing_template_decl,
3030 processing_template_decl,
3031 decl, TREE_TYPE (parm));
3032 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3033 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3035 DECL_ARTIFICIAL (decl) = 1;
3036 SET_DECL_TEMPLATE_PARM_P (decl);
3038 parm = build_tree_list (defval, parm);
3039 return chainon (list, parm);
3042 /* The end of a template parameter list has been reached. Process the
3043 tree list into a parameter vector, converting each parameter into a more
3044 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3048 end_template_parm_list (tree parms)
3052 tree saved_parmlist = make_tree_vec (list_length (parms));
3054 current_template_parms
3055 = tree_cons (size_int (processing_template_decl),
3056 saved_parmlist, current_template_parms);
3058 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3060 next = TREE_CHAIN (parm);
3061 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3062 TREE_CHAIN (parm) = NULL_TREE;
3065 --processing_template_parmlist;
3067 return saved_parmlist;
3070 /* end_template_decl is called after a template declaration is seen. */
3073 end_template_decl (void)
3075 reset_specialization ();
3077 if (! processing_template_decl)
3080 /* This matches the pushlevel in begin_template_parm_list. */
3083 --processing_template_decl;
3084 current_template_parms = TREE_CHAIN (current_template_parms);
3087 /* Within the declaration of a template, return all levels of template
3088 parameters that apply. The template parameters are represented as
3089 a TREE_VEC, in the form documented in cp-tree.h for template
3093 current_template_args (void)
3096 tree args = NULL_TREE;
3097 int length = TMPL_PARMS_DEPTH (current_template_parms);
3100 /* If there is only one level of template parameters, we do not
3101 create a TREE_VEC of TREE_VECs. Instead, we return a single
3102 TREE_VEC containing the arguments. */
3104 args = make_tree_vec (length);
3106 for (header = current_template_parms; header; header = TREE_CHAIN (header))
3108 tree a = copy_node (TREE_VALUE (header));
3111 TREE_TYPE (a) = NULL_TREE;
3112 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3114 tree t = TREE_VEC_ELT (a, i);
3116 /* T will be a list if we are called from within a
3117 begin/end_template_parm_list pair, but a vector directly
3118 if within a begin/end_member_template_processing pair. */
3119 if (TREE_CODE (t) == TREE_LIST)
3123 if (t != error_mark_node)
3125 if (TREE_CODE (t) == TYPE_DECL
3126 || TREE_CODE (t) == TEMPLATE_DECL)
3130 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3132 /* Turn this argument into a TYPE_ARGUMENT_PACK
3133 with a single element, which expands T. */
3134 tree vec = make_tree_vec (1);
3135 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3137 t = make_node (TYPE_ARGUMENT_PACK);
3138 SET_ARGUMENT_PACK_ARGS (t, vec);
3143 t = DECL_INITIAL (t);
3145 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3147 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3148 with a single element, which expands T. */
3149 tree vec = make_tree_vec (1);
3150 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3151 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3153 t = make_node (NONTYPE_ARGUMENT_PACK);
3154 SET_ARGUMENT_PACK_ARGS (t, vec);
3155 TREE_TYPE (t) = type;
3158 TREE_VEC_ELT (a, i) = t;
3164 TREE_VEC_ELT (args, --l) = a;
3172 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3173 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3174 a member template. Used by push_template_decl below. */
3177 build_template_decl (tree decl, tree parms, bool member_template_p)
3179 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3180 DECL_TEMPLATE_PARMS (tmpl) = parms;
3181 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3182 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3183 if (DECL_LANG_SPECIFIC (decl))
3185 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
3186 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
3187 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
3188 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
3189 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
3190 if (DECL_OVERLOADED_OPERATOR_P (decl))
3191 SET_OVERLOADED_OPERATOR_CODE (tmpl,
3192 DECL_OVERLOADED_OPERATOR_P (decl));
3198 struct template_parm_data
3200 /* The level of the template parameters we are currently
3204 /* The index of the specialization argument we are currently
3208 /* An array whose size is the number of template parameters. The
3209 elements are nonzero if the parameter has been used in any one
3210 of the arguments processed so far. */
3213 /* An array whose size is the number of template arguments. The
3214 elements are nonzero if the argument makes use of template
3215 parameters of this level. */
3216 int* arg_uses_template_parms;
3219 /* Subroutine of push_template_decl used to see if each template
3220 parameter in a partial specialization is used in the explicit
3221 argument list. If T is of the LEVEL given in DATA (which is
3222 treated as a template_parm_data*), then DATA->PARMS is marked
3226 mark_template_parm (tree t, void* data)
3230 struct template_parm_data* tpd = (struct template_parm_data*) data;
3232 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3234 level = TEMPLATE_PARM_LEVEL (t);
3235 idx = TEMPLATE_PARM_IDX (t);
3239 level = TEMPLATE_TYPE_LEVEL (t);
3240 idx = TEMPLATE_TYPE_IDX (t);
3243 if (level == tpd->level)
3245 tpd->parms[idx] = 1;
3246 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
3249 /* Return zero so that for_each_template_parm will continue the
3250 traversal of the tree; we want to mark *every* template parm. */
3254 /* Process the partial specialization DECL. */
3257 process_partial_specialization (tree decl)
3259 tree type = TREE_TYPE (decl);
3260 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
3261 tree specargs = CLASSTYPE_TI_ARGS (type);
3262 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
3263 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3264 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
3265 int nargs = TREE_VEC_LENGTH (inner_args);
3266 int ntparms = TREE_VEC_LENGTH (inner_parms);
3268 int did_error_intro = 0;
3269 struct template_parm_data tpd;
3270 struct template_parm_data tpd2;
3272 /* We check that each of the template parameters given in the
3273 partial specialization is used in the argument list to the
3274 specialization. For example:
3276 template <class T> struct S;
3277 template <class T> struct S<T*>;
3279 The second declaration is OK because `T*' uses the template
3280 parameter T, whereas
3282 template <class T> struct S<int>;
3284 is no good. Even trickier is:
3295 The S2<T> declaration is actually invalid; it is a
3296 full-specialization. Of course,
3299 struct S2<T (*)(U)>;
3301 or some such would have been OK. */
3302 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
3303 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
3304 memset (tpd.parms, 0, sizeof (int) * ntparms);
3306 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
3307 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
3308 for (i = 0; i < nargs; ++i)
3310 tpd.current_arg = i;
3311 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
3312 &mark_template_parm,
3316 for (i = 0; i < ntparms; ++i)
3317 if (tpd.parms[i] == 0)
3319 /* One of the template parms was not used in the
3321 if (!did_error_intro)
3323 error ("template parameters not used in partial specialization:");
3324 did_error_intro = 1;
3327 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
3330 /* [temp.class.spec]
3332 The argument list of the specialization shall not be identical to
3333 the implicit argument list of the primary template. */
3334 if (comp_template_args
3336 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
3338 error ("partial specialization %qT does not specialize any template arguments", type);
3340 /* [temp.class.spec]
3342 A partially specialized non-type argument expression shall not
3343 involve template parameters of the partial specialization except
3344 when the argument expression is a simple identifier.
3346 The type of a template parameter corresponding to a specialized
3347 non-type argument shall not be dependent on a parameter of the
3350 Also, we verify that pack expansions only occur at the
3351 end of the argument list. */
3352 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
3354 for (i = 0; i < nargs; ++i)
3356 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
3357 tree arg = TREE_VEC_ELT (inner_args, i);
3358 tree packed_args = NULL_TREE;
3361 if (ARGUMENT_PACK_P (arg))
3363 /* Extract the arguments from the argument pack. We'll be
3364 iterating over these in the following loop. */
3365 packed_args = ARGUMENT_PACK_ARGS (arg);
3366 len = TREE_VEC_LENGTH (packed_args);
3369 for (j = 0; j < len; j++)
3372 /* Get the Jth argument in the parameter pack. */
3373 arg = TREE_VEC_ELT (packed_args, j);
3375 if (PACK_EXPANSION_P (arg))
3377 /* Pack expansions must come at the end of the
3379 if ((packed_args && j < len - 1)
3380 || (!packed_args && i < nargs - 1))
3382 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3383 error ("parameter pack argument %qE must be at the end of the template argument list", arg);
3385 error ("parameter pack argument %qT must be at the end of the template argument list", arg);
3389 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3390 /* We only care about the pattern. */
3391 arg = PACK_EXPANSION_PATTERN (arg);
3393 if (/* These first two lines are the `non-type' bit. */
3395 && TREE_CODE (arg) != TEMPLATE_DECL
3396 /* This next line is the `argument expression is not just a
3397 simple identifier' condition and also the `specialized
3398 non-type argument' bit. */
3399 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
3401 if ((!packed_args && tpd.arg_uses_template_parms[i])
3402 || (packed_args && uses_template_parms (arg)))
3403 error ("template argument %qE involves template parameter(s)",
3407 /* Look at the corresponding template parameter,
3408 marking which template parameters its type depends
3410 tree type = TREE_TYPE (parm);
3414 /* We haven't yet initialized TPD2. Do so now. */
3415 tpd2.arg_uses_template_parms
3416 = (int *) alloca (sizeof (int) * nargs);
3417 /* The number of parameters here is the number in the
3418 main template, which, as checked in the assertion
3420 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
3422 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
3425 /* Mark the template parameters. But this time, we're
3426 looking for the template parameters of the main
3427 template, not in the specialization. */
3428 tpd2.current_arg = i;
3429 tpd2.arg_uses_template_parms[i] = 0;
3430 memset (tpd2.parms, 0, sizeof (int) * nargs);
3431 for_each_template_parm (type,
3432 &mark_template_parm,
3436 if (tpd2.arg_uses_template_parms [i])
3438 /* The type depended on some template parameters.
3439 If they are fully specialized in the
3440 specialization, that's OK. */
3442 for (j = 0; j < nargs; ++j)
3443 if (tpd2.parms[j] != 0
3444 && tpd.arg_uses_template_parms [j])
3446 error ("type %qT of template argument %qE depends "
3447 "on template parameter(s)",
3458 if (retrieve_specialization (maintmpl, specargs,
3459 /*class_specializations_p=*/true))
3460 /* We've already got this specialization. */
3463 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
3464 = tree_cons (specargs, inner_parms,
3465 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
3466 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
3470 /* Check that a template declaration's use of default arguments is not
3471 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
3472 nonzero if DECL is the thing declared by a primary template.
3473 IS_PARTIAL is nonzero if DECL is a partial specialization.
3476 IS_FRIEND_DECL is nonzero if DECL is a friend function template
3477 declaration (but not a definition); 1 indicates a declaration, 2
3478 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
3479 emitted for extraneous default arguments.
3481 Returns TRUE if there were no errors found, FALSE otherwise. */
3484 check_default_tmpl_args (tree decl, tree parms, int is_primary,
3485 int is_partial, int is_friend_decl)
3488 int last_level_to_check;
3490 bool no_errors = true;
3494 A default template-argument shall not be specified in a
3495 function template declaration or a function template definition, nor
3496 in the template-parameter-list of the definition of a member of a
3499 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
3500 /* You can't have a function template declaration in a local
3501 scope, nor you can you define a member of a class template in a
3505 if (current_class_type
3506 && !TYPE_BEING_DEFINED (current_class_type)
3507 && DECL_LANG_SPECIFIC (decl)
3508 /* If this is either a friend defined in the scope of the class
3509 or a member function. */
3510 && (DECL_FUNCTION_MEMBER_P (decl)
3511 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
3512 : DECL_FRIEND_CONTEXT (decl)
3513 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
3515 /* And, if it was a member function, it really was defined in
3516 the scope of the class. */
3517 && (!DECL_FUNCTION_MEMBER_P (decl)
3518 || DECL_INITIALIZED_IN_CLASS_P (decl)))
3519 /* We already checked these parameters when the template was
3520 declared, so there's no need to do it again now. This function
3521 was defined in class scope, but we're processing it's body now
3522 that the class is complete. */
3525 /* Core issue 226 (C++0x only): the following only applies to class
3527 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
3531 If a template-parameter has a default template-argument, all
3532 subsequent template-parameters shall have a default
3533 template-argument supplied. */
3534 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
3536 tree inner_parms = TREE_VALUE (parm_level);
3537 int ntparms = TREE_VEC_LENGTH (inner_parms);
3538 int seen_def_arg_p = 0;
3541 for (i = 0; i < ntparms; ++i)
3543 tree parm = TREE_VEC_ELT (inner_parms, i);
3545 if (parm == error_mark_node)
3548 if (TREE_PURPOSE (parm))
3550 else if (seen_def_arg_p)
3552 error ("no default argument for %qD", TREE_VALUE (parm));
3553 /* For better subsequent error-recovery, we indicate that
3554 there should have been a default argument. */
3555 TREE_PURPOSE (parm) = error_mark_node;
3562 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
3566 /* For an ordinary class template, default template arguments are
3567 allowed at the innermost level, e.g.:
3568 template <class T = int>
3570 but, in a partial specialization, they're not allowed even
3571 there, as we have in [temp.class.spec]:
3573 The template parameter list of a specialization shall not
3574 contain default template argument values.
3576 So, for a partial specialization, or for a function template
3577 (in C++98/C++03), we look at all of them. */
3580 /* But, for a primary class template that is not a partial
3581 specialization we look at all template parameters except the
3583 parms = TREE_CHAIN (parms);
3585 /* Figure out what error message to issue. */
3586 if (is_friend_decl == 2)
3587 msg = "default template arguments may not be used in function template friend re-declaration";
3588 else if (is_friend_decl)
3589 msg = "default template arguments may not be used in function template friend declarations";
3590 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
3591 msg = "default template arguments may not be used in function templates";
3592 else if (is_partial)
3593 msg = "default template arguments may not be used in partial specializations";
3595 msg = "default argument for template parameter for class enclosing %qD";
3597 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
3598 /* If we're inside a class definition, there's no need to
3599 examine the parameters to the class itself. On the one
3600 hand, they will be checked when the class is defined, and,
3601 on the other, default arguments are valid in things like:
3602 template <class T = double>
3603 struct S { template <class U> void f(U); };
3604 Here the default argument for `S' has no bearing on the
3605 declaration of `f'. */
3606 last_level_to_check = template_class_depth (current_class_type) + 1;
3608 /* Check everything. */
3609 last_level_to_check = 0;
3611 for (parm_level = parms;
3612 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
3613 parm_level = TREE_CHAIN (parm_level))
3615 tree inner_parms = TREE_VALUE (parm_level);
3619 ntparms = TREE_VEC_LENGTH (inner_parms);
3620 for (i = 0; i < ntparms; ++i)
3622 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
3625 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
3630 if (is_friend_decl == 2)
3637 /* Clear out the default argument so that we are not
3639 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
3643 /* At this point, if we're still interested in issuing messages,
3644 they must apply to classes surrounding the object declared. */
3646 msg = "default argument for template parameter for class enclosing %qD";
3652 /* Worker for push_template_decl_real, called via
3653 for_each_template_parm. DATA is really an int, indicating the
3654 level of the parameters we are interested in. If T is a template
3655 parameter of that level, return nonzero. */
3658 template_parm_this_level_p (tree t, void* data)
3660 int this_level = *(int *)data;
3663 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3664 level = TEMPLATE_PARM_LEVEL (t);
3666 level = TEMPLATE_TYPE_LEVEL (t);
3667 return level == this_level;
3670 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
3671 parameters given by current_template_args, or reuses a
3672 previously existing one, if appropriate. Returns the DECL, or an
3673 equivalent one, if it is replaced via a call to duplicate_decls.
3675 If IS_FRIEND is true, DECL is a friend declaration. */
3678 push_template_decl_real (tree decl, bool is_friend)
3686 int new_template_p = 0;
3687 /* True if the template is a member template, in the sense of
3689 bool member_template_p = false;
3691 if (decl == error_mark_node)
3694 /* See if this is a partial specialization. */
3695 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
3696 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3697 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
3699 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
3703 /* For a friend, we want the context of the friend function, not
3704 the type of which it is a friend. */
3705 ctx = DECL_CONTEXT (decl);
3706 else if (CP_DECL_CONTEXT (decl)
3707 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
3708 /* In the case of a virtual function, we want the class in which
3710 ctx = CP_DECL_CONTEXT (decl);
3712 /* Otherwise, if we're currently defining some class, the DECL
3713 is assumed to be a member of the class. */
3714 ctx = current_scope ();
3716 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
3719 if (!DECL_CONTEXT (decl))
3720 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
3722 /* See if this is a primary template. */
3723 if (is_friend && ctx)
3724 /* A friend template that specifies a class context, i.e.
3725 template <typename T> friend void A<T>::f();
3729 primary = template_parm_scope_p ();
3733 if (DECL_CLASS_SCOPE_P (decl))
3734 member_template_p = true;
3735 if (TREE_CODE (decl) == TYPE_DECL
3736 && ANON_AGGRNAME_P (DECL_NAME (decl)))
3737 error ("template class without a name");
3738 else if (TREE_CODE (decl) == FUNCTION_DECL)
3740 if (DECL_DESTRUCTOR_P (decl))
3744 A destructor shall not be a member template. */
3745 error ("destructor %qD declared as member template", decl);
3746 return error_mark_node;
3748 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
3749 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
3750 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
3751 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
3752 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
3753 == void_list_node)))
3755 /* [basic.stc.dynamic.allocation]
3757 An allocation function can be a function
3758 template. ... Template allocation functions shall
3759 have two or more parameters. */
3760 error ("invalid template declaration of %qD", decl);
3761 return error_mark_node;
3764 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3765 && CLASS_TYPE_P (TREE_TYPE (decl)))
3769 error ("template declaration of %q#D", decl);
3770 return error_mark_node;
3774 /* Check to see that the rules regarding the use of default
3775 arguments are not being violated. */
3776 check_default_tmpl_args (decl, current_template_parms,
3777 primary, is_partial, /*is_friend_decl=*/0);
3779 /* Ensure that there are no parameter packs in the type of this
3780 declaration that have not been expanded. */
3781 if (TREE_CODE (decl) == FUNCTION_DECL)
3783 /* Check each of the arguments individually to see if there are
3784 any bare parameter packs. */
3785 tree type = TREE_TYPE (decl);
3786 tree arg = DECL_ARGUMENTS (decl);
3787 tree argtype = TYPE_ARG_TYPES (type);
3789 while (arg && argtype)
3791 if (!FUNCTION_PARAMETER_PACK_P (arg)
3792 && !check_for_bare_parameter_packs (TREE_TYPE (arg)))
3794 /* This is a PARM_DECL that contains unexpanded parameter
3795 packs. We have already complained about this in the
3796 check_for_bare_parameter_packs call, so just replace
3797 these types with ERROR_MARK_NODE. */
3798 TREE_TYPE (arg) = error_mark_node;
3799 TREE_VALUE (argtype) = error_mark_node;
3802 arg = TREE_CHAIN (arg);
3803 argtype = TREE_CHAIN (argtype);
3806 /* Check for bare parameter packs in the return type and the
3807 exception specifiers. */
3808 check_for_bare_parameter_packs (TREE_TYPE (type));
3809 check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type));
3812 check_for_bare_parameter_packs (TREE_TYPE (decl));
3815 return process_partial_specialization (decl);
3817 /* A primary class template can only have one parameter pack, at the
3818 end of the template parameter list. */
3819 if (primary && TREE_CODE (decl) == TYPE_DECL)
3822 = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3823 int i, len = TREE_VEC_LENGTH (inner_parms);
3824 for (i = 0; i < len - 1; i++)
3826 tree parm = TREE_VALUE (TREE_VEC_ELT (inner_parms, i));
3828 if (template_parameter_pack_p (parm))
3830 if (TREE_CODE (parm) == PARM_DECL)
3831 error ("parameter pack %qE must be at the end of the"
3832 " template parameter list", parm);
3834 error ("parameter pack %qT must be at the end of the"
3835 " template parameter list", TREE_TYPE (parm));
3840 args = current_template_args ();
3843 || TREE_CODE (ctx) == FUNCTION_DECL
3844 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3845 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3847 if (DECL_LANG_SPECIFIC (decl)
3848 && DECL_TEMPLATE_INFO (decl)
3849 && DECL_TI_TEMPLATE (decl))
3850 tmpl = DECL_TI_TEMPLATE (decl);
3851 /* If DECL is a TYPE_DECL for a class-template, then there won't
3852 be DECL_LANG_SPECIFIC. The information equivalent to
3853 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3854 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3855 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3856 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3858 /* Since a template declaration already existed for this
3859 class-type, we must be redeclaring it here. Make sure
3860 that the redeclaration is valid. */
3861 redeclare_class_template (TREE_TYPE (decl),
3862 current_template_parms);
3863 /* We don't need to create a new TEMPLATE_DECL; just use the
3864 one we already had. */
3865 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3869 tmpl = build_template_decl (decl, current_template_parms,
3873 if (DECL_LANG_SPECIFIC (decl)
3874 && DECL_TEMPLATE_SPECIALIZATION (decl))
3876 /* A specialization of a member template of a template
3878 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3879 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3880 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3886 tree a, t, current, parms;
3888 tree tinfo = get_template_info (decl);
3892 error ("template definition of non-template %q#D", decl);
3896 tmpl = TI_TEMPLATE (tinfo);
3898 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3899 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3900 && DECL_TEMPLATE_SPECIALIZATION (decl)
3901 && DECL_MEMBER_TEMPLATE_P (tmpl))
3905 /* The declaration is a specialization of a member
3906 template, declared outside the class. Therefore, the
3907 innermost template arguments will be NULL, so we
3908 replace them with the arguments determined by the
3909 earlier call to check_explicit_specialization. */
3910 args = DECL_TI_ARGS (decl);
3913 = build_template_decl (decl, current_template_parms,
3915 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3916 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3917 DECL_TI_TEMPLATE (decl) = new_tmpl;
3918 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3919 DECL_TEMPLATE_INFO (new_tmpl)
3920 = tree_cons (tmpl, args, NULL_TREE);
3922 register_specialization (new_tmpl,
3923 most_general_template (tmpl),
3929 /* Make sure the template headers we got make sense. */
3931 parms = DECL_TEMPLATE_PARMS (tmpl);
3932 i = TMPL_PARMS_DEPTH (parms);
3933 if (TMPL_ARGS_DEPTH (args) != i)
3935 error ("expected %d levels of template parms for %q#D, got %d",
3936 i, decl, TMPL_ARGS_DEPTH (args));
3939 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3941 a = TMPL_ARGS_LEVEL (args, i);
3942 t = INNERMOST_TEMPLATE_PARMS (parms);
3944 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3946 if (current == decl)
3947 error ("got %d template parameters for %q#D",
3948 TREE_VEC_LENGTH (a), decl);
3950 error ("got %d template parameters for %q#T",
3951 TREE_VEC_LENGTH (a), current);
3952 error (" but %d required", TREE_VEC_LENGTH (t));
3953 return error_mark_node;
3956 if (current == decl)
3959 current = (TYPE_P (current)
3960 ? TYPE_CONTEXT (current)
3961 : DECL_CONTEXT (current));
3964 /* Check that the parms are used in the appropriate qualifying scopes
3965 in the declarator. */
3966 if (!comp_template_args
3968 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
3971 template arguments to %qD do not match original template %qD",
3972 decl, DECL_TEMPLATE_RESULT (tmpl));
3973 if (!uses_template_parms (TI_ARGS (tinfo)))
3974 inform ("use template<> for an explicit specialization");
3975 /* Avoid crash in import_export_decl. */
3976 DECL_INTERFACE_KNOWN (decl) = 1;
3977 return error_mark_node;
3981 DECL_TEMPLATE_RESULT (tmpl) = decl;
3982 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3984 /* Push template declarations for global functions and types. Note
3985 that we do not try to push a global template friend declared in a
3986 template class; such a thing may well depend on the template
3987 parameters of the class. */
3988 if (new_template_p && !ctx
3989 && !(is_friend && template_class_depth (current_class_type) > 0))
3991 tmpl = pushdecl_namespace_level (tmpl, is_friend);
3992 if (tmpl == error_mark_node)
3993 return error_mark_node;
3995 /* Hide template friend classes that haven't been declared yet. */
3996 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
3998 DECL_ANTICIPATED (tmpl) = 1;
3999 DECL_FRIEND_P (tmpl) = 1;
4005 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4008 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4009 if (DECL_CONV_FN_P (tmpl))
4011 int depth = TMPL_PARMS_DEPTH (parms);
4013 /* It is a conversion operator. See if the type converted to
4014 depends on innermost template operands. */
4016 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4018 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4021 /* Give template template parms a DECL_CONTEXT of the template
4022 for which they are a parameter. */
4023 parms = INNERMOST_TEMPLATE_PARMS (parms);
4024 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4026 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4027 if (TREE_CODE (parm) == TEMPLATE_DECL)
4028 DECL_CONTEXT (parm) = tmpl;
4032 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4033 back to its most general template. If TMPL is a specialization,
4034 ARGS may only have the innermost set of arguments. Add the missing
4035 argument levels if necessary. */
4036 if (DECL_TEMPLATE_INFO (tmpl))
4037 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4039 info = tree_cons (tmpl, args, NULL_TREE);
4041 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4042 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4043 else if (DECL_LANG_SPECIFIC (decl))
4044 DECL_TEMPLATE_INFO (decl) = info;
4046 return DECL_TEMPLATE_RESULT (tmpl);
4050 push_template_decl (tree decl)
4052 return push_template_decl_real (decl, false);
4055 /* Called when a class template TYPE is redeclared with the indicated
4056 template PARMS, e.g.:
4058 template <class T> struct S;
4059 template <class T> struct S {}; */
4062 redeclare_class_template (tree type, tree parms)
4068 if (!TYPE_TEMPLATE_INFO (type))
4070 error ("%qT is not a template type", type);
4074 tmpl = TYPE_TI_TEMPLATE (type);
4075 if (!PRIMARY_TEMPLATE_P (tmpl))
4076 /* The type is nested in some template class. Nothing to worry
4077 about here; there are no new template parameters for the nested
4083 error ("template specifiers not specified in declaration of %qD",
4088 parms = INNERMOST_TEMPLATE_PARMS (parms);
4089 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4091 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4093 error ("previous declaration %q+D", tmpl);
4094 error ("used %d template parameter(s) instead of %d",
4095 TREE_VEC_LENGTH (tmpl_parms),
4096 TREE_VEC_LENGTH (parms));
4100 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4107 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4108 || TREE_VEC_ELT (parms, i) == error_mark_node)
4111 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4112 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4113 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4114 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4116 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
4118 if (tmpl_parm != error_mark_node
4119 && (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
4120 || (TREE_CODE (tmpl_parm) != TYPE_DECL
4121 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))))
4123 error ("template parameter %q+#D", tmpl_parm);
4124 error ("redeclared here as %q#D", parm);
4128 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
4130 /* We have in [temp.param]:
4132 A template-parameter may not be given default arguments
4133 by two different declarations in the same scope. */
4134 error ("redefinition of default argument for %q#D", parm);
4135 error ("%J original definition appeared here", tmpl_parm);
4139 if (parm_default != NULL_TREE)
4140 /* Update the previous template parameters (which are the ones
4141 that will really count) with the new default value. */
4142 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
4143 else if (tmpl_default != NULL_TREE)
4144 /* Update the new parameters, too; they'll be used as the
4145 parameters for any members. */
4146 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
4152 /* Simplify EXPR if it is a non-dependent expression. Returns the
4153 (possibly simplified) expression. */
4156 fold_non_dependent_expr (tree expr)
4158 if (expr == NULL_TREE)
4161 /* If we're in a template, but EXPR isn't value dependent, simplify
4162 it. We're supposed to treat:
4164 template <typename T> void f(T[1 + 1]);
4165 template <typename T> void f(T[2]);
4167 as two declarations of the same function, for example. */
4168 if (processing_template_decl
4169 && !type_dependent_expression_p (expr)
4170 && !value_dependent_expression_p (expr))
4172 HOST_WIDE_INT saved_processing_template_decl;
4174 saved_processing_template_decl = processing_template_decl;
4175 processing_template_decl = 0;
4176 expr = tsubst_copy_and_build (expr,
4179 /*in_decl=*/NULL_TREE,
4180 /*function_p=*/false,
4181 /*integral_constant_expression_p=*/true);
4182 processing_template_decl = saved_processing_template_decl;
4187 /* EXPR is an expression which is used in a constant-expression context.
4188 For instance, it could be a VAR_DECL with a constant initializer.
4189 Extract the innest constant expression.
4191 This is basically a more powerful version of
4192 integral_constant_value, which can be used also in templates where
4193 initializers can maintain a syntactic rather than semantic form
4194 (even if they are non-dependent, for access-checking purposes). */
4197 fold_decl_constant_value (tree expr)
4199 tree const_expr = expr;
4202 expr = fold_non_dependent_expr (const_expr);
4203 const_expr = integral_constant_value (expr);
4205 while (expr != const_expr);
4210 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
4211 must be a function or a pointer-to-function type, as specified
4212 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
4213 and check that the resulting function has external linkage. */
4216 convert_nontype_argument_function (tree type, tree expr)
4221 fn = instantiate_type (type, fns, tf_none);
4222 if (fn == error_mark_node)
4223 return error_mark_node;
4226 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
4227 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
4228 if (TREE_CODE (fn_no_ptr) == BASELINK)
4229 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
4231 /* [temp.arg.nontype]/1
4233 A template-argument for a non-type, non-template template-parameter
4236 -- the address of an object or function with external linkage. */
4237 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
4239 error ("%qE is not a valid template argument for type %qT "
4240 "because function %qD has not external linkage",
4241 expr, type, fn_no_ptr);
4248 /* Attempt to convert the non-type template parameter EXPR to the
4249 indicated TYPE. If the conversion is successful, return the
4250 converted value. If the conversion is unsuccessful, return
4251 NULL_TREE if we issued an error message, or error_mark_node if we
4252 did not. We issue error messages for out-and-out bad template
4253 parameters, but not simply because the conversion failed, since we
4254 might be just trying to do argument deduction. Both TYPE and EXPR
4255 must be non-dependent.
4257 The conversion follows the special rules described in
4258 [temp.arg.nontype], and it is much more strict than an implicit
4261 This function is called twice for each template argument (see
4262 lookup_template_class for a more accurate description of this
4263 problem). This means that we need to handle expressions which
4264 are not valid in a C++ source, but can be created from the
4265 first call (for instance, casts to perform conversions). These
4266 hacks can go away after we fix the double coercion problem. */
4269 convert_nontype_argument (tree type, tree expr)
4273 /* Detect immediately string literals as invalid non-type argument.
4274 This special-case is not needed for correctness (we would easily
4275 catch this later), but only to provide better diagnostic for this
4276 common user mistake. As suggested by DR 100, we do not mention
4277 linkage issues in the diagnostic as this is not the point. */
4278 if (TREE_CODE (expr) == STRING_CST)
4280 error ("%qE is not a valid template argument for type %qT "
4281 "because string literals can never be used in this context",
4286 /* If we are in a template, EXPR may be non-dependent, but still
4287 have a syntactic, rather than semantic, form. For example, EXPR
4288 might be a SCOPE_REF, rather than the VAR_DECL to which the
4289 SCOPE_REF refers. Preserving the qualifying scope is necessary
4290 so that access checking can be performed when the template is
4291 instantiated -- but here we need the resolved form so that we can
4292 convert the argument. */
4293 expr = fold_non_dependent_expr (expr);
4294 if (error_operand_p (expr))
4295 return error_mark_node;
4296 expr_type = TREE_TYPE (expr);
4298 /* HACK: Due to double coercion, we can get a
4299 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
4300 which is the tree that we built on the first call (see
4301 below when coercing to reference to object or to reference to
4302 function). We just strip everything and get to the arg.
4303 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
4305 if (TREE_CODE (expr) == NOP_EXPR)
4307 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
4309 /* ??? Maybe we could use convert_from_reference here, but we
4310 would need to relax its constraints because the NOP_EXPR
4311 could actually change the type to something more cv-qualified,
4312 and this is not folded by convert_from_reference. */
4313 tree addr = TREE_OPERAND (expr, 0);
4314 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
4315 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
4316 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
4317 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4318 (TREE_TYPE (expr_type),
4319 TREE_TYPE (TREE_TYPE (addr))));
4321 expr = TREE_OPERAND (addr, 0);
4322 expr_type = TREE_TYPE (expr);
4325 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
4326 parameter is a pointer to object, through decay and
4327 qualification conversion. Let's strip everything. */
4328 else if (TYPE_PTROBV_P (type))
4331 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
4332 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
4333 /* Skip the ADDR_EXPR only if it is part of the decay for
4334 an array. Otherwise, it is part of the original argument
4335 in the source code. */
4336 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
4337 expr = TREE_OPERAND (expr, 0);
4338 expr_type = TREE_TYPE (expr);
4342 /* [temp.arg.nontype]/5, bullet 1
4344 For a non-type template-parameter of integral or enumeration type,
4345 integral promotions (_conv.prom_) and integral conversions
4346 (_conv.integral_) are applied. */
4347 if (INTEGRAL_TYPE_P (type))
4349 if (!INTEGRAL_TYPE_P (expr_type))
4350 return error_mark_node;
4352 expr = fold_decl_constant_value (expr);
4353 /* Notice that there are constant expressions like '4 % 0' which
4354 do not fold into integer constants. */
4355 if (TREE_CODE (expr) != INTEGER_CST)
4357 error ("%qE is not a valid template argument for type %qT "
4358 "because it is a non-constant expression", expr, type);
4362 /* At this point, an implicit conversion does what we want,
4363 because we already know that the expression is of integral
4365 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
4366 if (expr == error_mark_node)
4367 return error_mark_node;
4369 /* Conversion was allowed: fold it to a bare integer constant. */
4372 /* [temp.arg.nontype]/5, bullet 2
4374 For a non-type template-parameter of type pointer to object,
4375 qualification conversions (_conv.qual_) and the array-to-pointer
4376 conversion (_conv.array_) are applied. */
4377 else if (TYPE_PTROBV_P (type))
4379 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
4381 A template-argument for a non-type, non-template template-parameter
4382 shall be one of: [...]
4384 -- the name of a non-type template-parameter;
4385 -- the address of an object or function with external linkage, [...]
4386 expressed as "& id-expression" where the & is optional if the name
4387 refers to a function or array, or if the corresponding
4388 template-parameter is a reference.
4390 Here, we do not care about functions, as they are invalid anyway
4391 for a parameter of type pointer-to-object. */
4393 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
4394 /* Non-type template parameters are OK. */
4396 else if (TREE_CODE (expr) != ADDR_EXPR
4397 && TREE_CODE (expr_type) != ARRAY_TYPE)
4399 if (TREE_CODE (expr) == VAR_DECL)
4401 error ("%qD is not a valid template argument "
4402 "because %qD is a variable, not the address of "
4407 /* Other values, like integer constants, might be valid
4408 non-type arguments of some other type. */
4409 return error_mark_node;
4415 decl = ((TREE_CODE (expr) == ADDR_EXPR)
4416 ? TREE_OPERAND (expr, 0) : expr);
4417 if (TREE_CODE (decl) != VAR_DECL)
4419 error ("%qE is not a valid template argument of type %qT "
4420 "because %qE is not a variable",
4424 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
4426 error ("%qE is not a valid template argument of type %qT "
4427 "because %qD does not have external linkage",
4433 expr = decay_conversion (expr);
4434 if (expr == error_mark_node)
4435 return error_mark_node;
4437 expr = perform_qualification_conversions (type, expr);
4438 if (expr == error_mark_node)
4439 return error_mark_node;
4441 /* [temp.arg.nontype]/5, bullet 3
4443 For a non-type template-parameter of type reference to object, no
4444 conversions apply. The type referred to by the reference may be more
4445 cv-qualified than the (otherwise identical) type of the
4446 template-argument. The template-parameter is bound directly to the
4447 template-argument, which must be an lvalue. */
4448 else if (TYPE_REF_OBJ_P (type))
4450 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
4452 return error_mark_node;
4454 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
4456 error ("%qE is not a valid template argument for type %qT "
4457 "because of conflicts in cv-qualification", expr, type);
4461 if (!real_lvalue_p (expr))
4463 error ("%qE is not a valid template argument for type %qT "
4464 "because it is not an lvalue", expr, type);
4468 /* [temp.arg.nontype]/1
4470 A template-argument for a non-type, non-template template-parameter
4471 shall be one of: [...]
4473 -- the address of an object or function with external linkage. */
4474 if (!DECL_EXTERNAL_LINKAGE_P (expr))
4476 error ("%qE is not a valid template argument for type %qT "
4477 "because object %qD has not external linkage",
4482 expr = build_nop (type, build_address (expr));
4484 /* [temp.arg.nontype]/5, bullet 4
4486 For a non-type template-parameter of type pointer to function, only
4487 the function-to-pointer conversion (_conv.func_) is applied. If the
4488 template-argument represents a set of overloaded functions (or a
4489 pointer to such), the matching function is selected from the set
4491 else if (TYPE_PTRFN_P (type))
4493 /* If the argument is a template-id, we might not have enough
4494 context information to decay the pointer. */
4495 if (!type_unknown_p (expr_type))
4497 expr = decay_conversion (expr);
4498 if (expr == error_mark_node)
4499 return error_mark_node;
4502 expr = convert_nontype_argument_function (type, expr);
4503 if (!expr || expr == error_mark_node)
4506 /* [temp.arg.nontype]/5, bullet 5
4508 For a non-type template-parameter of type reference to function, no
4509 conversions apply. If the template-argument represents a set of
4510 overloaded functions, the matching function is selected from the set
4512 else if (TYPE_REFFN_P (type))
4514 if (TREE_CODE (expr) == ADDR_EXPR)
4516 error ("%qE is not a valid template argument for type %qT "
4517 "because it is a pointer", expr, type);
4518 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
4522 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
4523 if (!expr || expr == error_mark_node)
4526 expr = build_nop (type, build_address (expr));
4528 /* [temp.arg.nontype]/5, bullet 6
4530 For a non-type template-parameter of type pointer to member function,
4531 no conversions apply. If the template-argument represents a set of
4532 overloaded member functions, the matching member function is selected
4533 from the set (_over.over_). */
4534 else if (TYPE_PTRMEMFUNC_P (type))
4536 expr = instantiate_type (type, expr, tf_none);
4537 if (expr == error_mark_node)
4538 return error_mark_node;
4540 /* There is no way to disable standard conversions in
4541 resolve_address_of_overloaded_function (called by
4542 instantiate_type). It is possible that the call succeeded by
4543 converting &B::I to &D::I (where B is a base of D), so we need
4544 to reject this conversion here.
4546 Actually, even if there was a way to disable standard conversions,
4547 it would still be better to reject them here so that we can
4548 provide a superior diagnostic. */
4549 if (!same_type_p (TREE_TYPE (expr), type))
4551 /* Make sure we are just one standard conversion off. */
4552 gcc_assert (can_convert (type, TREE_TYPE (expr)));
4553 error ("%qE is not a valid template argument for type %qT "
4554 "because it is of type %qT", expr, type,
4556 inform ("standard conversions are not allowed in this context");
4560 /* [temp.arg.nontype]/5, bullet 7
4562 For a non-type template-parameter of type pointer to data member,
4563 qualification conversions (_conv.qual_) are applied. */
4564 else if (TYPE_PTRMEM_P (type))
4566 expr = perform_qualification_conversions (type, expr);
4567 if (expr == error_mark_node)
4570 /* A template non-type parameter must be one of the above. */
4574 /* Sanity check: did we actually convert the argument to the
4576 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
4581 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
4582 template template parameters. Both PARM_PARMS and ARG_PARMS are
4583 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
4586 Consider the example:
4587 template <class T> class A;
4588 template<template <class U> class TT> class B;
4590 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
4591 the parameters to A, and OUTER_ARGS contains A. */
4594 coerce_template_template_parms (tree parm_parms,
4596 tsubst_flags_t complain,
4600 int nparms, nargs, i;
4603 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
4604 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
4606 nparms = TREE_VEC_LENGTH (parm_parms);
4607 nargs = TREE_VEC_LENGTH (arg_parms);
4609 if (nargs != nparms)
4612 for (i = 0; i < nparms; ++i)
4614 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
4615 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
4618 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
4619 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
4621 if (arg == NULL_TREE || arg == error_mark_node
4622 || parm == NULL_TREE || parm == error_mark_node)
4625 if (TREE_CODE (arg) != TREE_CODE (parm))
4628 switch (TREE_CODE (parm))
4631 /* We encounter instantiations of templates like
4632 template <template <template <class> class> class TT>
4635 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
4636 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
4638 if (!coerce_template_template_parms
4639 (parmparm, argparm, complain, in_decl, outer_args))
4645 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))
4646 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg)))
4647 /* One is a parameter pack, the other is not. */
4652 /* The tsubst call is used to handle cases such as
4654 template <int> class C {};
4655 template <class T, template <T> class TT> class D {};
4658 i.e. the parameter list of TT depends on earlier parameters. */
4659 if (!dependent_type_p (TREE_TYPE (arg))
4661 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
4665 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
4666 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg)))
4667 /* One is a parameter pack, the other is not. */
4678 /* Convert the indicated template ARG as necessary to match the
4679 indicated template PARM. Returns the converted ARG, or
4680 error_mark_node if the conversion was unsuccessful. Error and
4681 warning messages are issued under control of COMPLAIN. This
4682 conversion is for the Ith parameter in the parameter list. ARGS is
4683 the full set of template arguments deduced so far. */
4686 convert_template_argument (tree parm,
4689 tsubst_flags_t complain,
4695 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
4697 if (TREE_CODE (arg) == TREE_LIST
4698 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
4700 /* The template argument was the name of some
4701 member function. That's usually
4702 invalid, but static members are OK. In any
4703 case, grab the underlying fields/functions
4704 and issue an error later if required. */
4705 orig_arg = TREE_VALUE (arg);
4706 TREE_TYPE (arg) = unknown_type_node;
4711 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
4712 requires_type = (TREE_CODE (parm) == TYPE_DECL
4713 || requires_tmpl_type);
4715 /* When determining whether an argument pack expansion is a template,
4716 look at the pattern. */
4717 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
4718 arg = PACK_EXPANSION_PATTERN (arg);
4721 ((TREE_CODE (arg) == TEMPLATE_DECL
4722 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
4723 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
4724 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
4727 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
4728 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
4729 arg = TYPE_STUB_DECL (arg);
4731 is_type = TYPE_P (arg) || is_tmpl_type;
4733 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
4734 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
4736 pedwarn ("to refer to a type member of a template parameter, "
4737 "use %<typename %E%>", orig_arg);
4739 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
4740 TREE_OPERAND (arg, 1),
4742 complain & tf_error);
4746 if (is_type != requires_type)
4750 if (complain & tf_error)
4752 error ("type/value mismatch at argument %d in template "
4753 "parameter list for %qD",
4756 error (" expected a constant of type %qT, got %qT",
4758 (is_tmpl_type ? DECL_NAME (arg) : orig_arg));
4759 else if (requires_tmpl_type)
4760 error (" expected a class template, got %qE", orig_arg);
4762 error (" expected a type, got %qE", orig_arg);
4765 return error_mark_node;
4767 if (is_tmpl_type ^ requires_tmpl_type)
4769 if (in_decl && (complain & tf_error))
4771 error ("type/value mismatch at argument %d in template "
4772 "parameter list for %qD",
4775 error (" expected a type, got %qT", DECL_NAME (arg));
4777 error (" expected a class template, got %qT", orig_arg);
4779 return error_mark_node;
4784 if (requires_tmpl_type)
4786 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
4787 /* The number of argument required is not known yet.
4788 Just accept it for now. */
4789 val = TREE_TYPE (arg);
4792 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
4795 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
4797 if (coerce_template_template_parms (parmparm, argparm,
4803 /* TEMPLATE_TEMPLATE_PARM node is preferred over
4805 if (val != error_mark_node)
4807 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
4808 val = TREE_TYPE (val);
4809 else if (TREE_CODE (val) == TYPE_PACK_EXPANSION
4810 && DECL_TEMPLATE_TEMPLATE_PARM_P (arg))
4812 val = TREE_TYPE (arg);
4813 val = make_pack_expansion (val);
4819 if (in_decl && (complain & tf_error))
4821 error ("type/value mismatch at argument %d in "
4822 "template parameter list for %qD",
4824 error (" expected a template of type %qD, got %qD",
4828 val = error_mark_node;
4834 /* We only form one instance of each template specialization.
4835 Therefore, if we use a non-canonical variant (i.e., a
4836 typedef), any future messages referring to the type will use
4837 the typedef, which is confusing if those future uses do not
4838 themselves also use the typedef. */
4840 val = canonical_type_variant (val);
4844 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
4846 if (invalid_nontype_parm_type_p (t, complain))
4847 return error_mark_node;
4849 if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
4850 /* We used to call digest_init here. However, digest_init
4851 will report errors, which we don't want when complain
4852 is zero. More importantly, digest_init will try too
4853 hard to convert things: for example, `0' should not be
4854 converted to pointer type at this point according to
4855 the standard. Accepting this is not merely an
4856 extension, since deciding whether or not these
4857 conversions can occur is part of determining which
4858 function template to call, or whether a given explicit
4859 argument specification is valid. */
4860 val = convert_nontype_argument (t, orig_arg);
4864 if (val == NULL_TREE)
4865 val = error_mark_node;
4866 else if (val == error_mark_node && (complain & tf_error))
4867 error ("could not convert template argument %qE to %qT", orig_arg, t);
4873 /* Coerces the remaining template arguments in INNER_ARGS (from
4874 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
4875 Returns the coerced argument pack. PARM_IDX is the position of this
4876 parameter in the template parameter list. ARGS is the original
4877 template argument list. */
4879 coerce_template_parameter_pack (tree parms,
4887 tsubst_flags_t complain)
4889 tree parm = TREE_VEC_ELT (parms, parm_idx);
4890 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
4893 tree packed_types = NULL_TREE;
4895 if (arg_idx > nargs)
4898 packed_args = make_tree_vec (nargs - arg_idx);
4900 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
4901 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
4903 /* When the template parameter is a non-type template
4904 parameter pack whose type uses parameter packs, we need
4905 to look at each of the template arguments
4906 separately. Build a vector of the types for these
4907 non-type template parameters in PACKED_TYPES. */
4909 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
4910 packed_types = tsubst_pack_expansion (expansion, args,
4913 if (packed_types == error_mark_node)
4914 return error_mark_node;
4916 /* Check that we have the right number of arguments. */
4918 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
4919 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
4922 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
4923 error ("wrong number of template arguments (%d, should be %d)",
4924 nargs, needed_parms);
4925 return error_mark_node;
4928 /* If we aren't able to check the actual arguments now
4929 (because they haven't been expanded yet), we can at least
4930 verify that all of the types used for the non-type
4931 template parameter pack are, in fact, valid for non-type
4932 template parameters. */
4934 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
4936 int j, len = TREE_VEC_LENGTH (packed_types);
4937 for (j = 0; j < len; ++j)
4939 tree t = TREE_VEC_ELT (packed_types, j);
4940 if (invalid_nontype_parm_type_p (t, complain))
4941 return error_mark_node;
4946 /* Convert the remaining arguments, which will be a part of the
4947 parameter pack "parm". */
4948 for (; arg_idx < nargs; ++arg_idx)
4950 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
4951 tree actual_parm = TREE_VALUE (parm);
4953 if (packed_types && !PACK_EXPANSION_P (arg))
4955 /* When we have a vector of types (corresponding to the
4956 non-type template parameter pack that uses parameter
4957 packs in its type, as mention above), and the
4958 argument is not an expansion (which expands to a
4959 currently unknown number of arguments), clone the
4960 parm and give it the next type in PACKED_TYPES. */
4961 actual_parm = copy_node (actual_parm);
4962 TREE_TYPE (actual_parm) =
4963 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
4966 if (arg != error_mark_node)
4967 arg = convert_template_argument (actual_parm,
4968 arg, new_args, complain, parm_idx,
4970 if (arg == error_mark_node)
4972 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
4975 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
4976 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
4977 argument_pack = make_node (TYPE_ARGUMENT_PACK);
4980 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
4981 TREE_TYPE (argument_pack)
4982 = tsubst (TREE_TYPE (TREE_VALUE (parm)), args, complain, in_decl);
4983 TREE_CONSTANT (argument_pack) = 1;
4986 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
4987 return argument_pack;
4990 /* Convert all template arguments to their appropriate types, and
4991 return a vector containing the innermost resulting template
4992 arguments. If any error occurs, return error_mark_node. Error and
4993 warning messages are issued under control of COMPLAIN.
4995 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
4996 for arguments not specified in ARGS. Otherwise, if
4997 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
4998 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
4999 USE_DEFAULT_ARGS is false, then all arguments must be specified in
5003 coerce_template_parms (tree parms,
5006 tsubst_flags_t complain,
5007 bool require_all_args,
5008 bool use_default_args)
5010 int nparms, nargs, parm_idx, arg_idx, lost = 0;
5013 tree new_inner_args;
5014 bool saved_skip_evaluation;
5016 /* When used as a boolean value, indicates whether this is a
5017 variadic template parameter list. Since it's an int, we can also
5018 subtract it from nparms to get the number of non-variadic
5023 = expand_template_argument_pack (INNERMOST_TEMPLATE_ARGS (args));
5025 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5026 nparms = TREE_VEC_LENGTH (parms);
5028 /* Determine if there are any parameter packs. */
5029 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
5031 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
5032 if (template_parameter_pack_p (tparm))
5039 if ((nargs > nparms - variadic_p && !variadic_p)
5040 || (nargs < nparms - variadic_p
5042 && (!use_default_args
5043 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
5044 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
5046 if (complain & tf_error)
5048 const char *or_more = "";
5051 or_more = " or more";
5055 error ("wrong number of template arguments (%d, should be %d%s)",
5056 nargs, nparms, or_more);
5059 error ("provided for %q+D", in_decl);
5062 return error_mark_node;
5065 /* We need to evaluate the template arguments, even though this
5066 template-id may be nested within a "sizeof". */
5067 saved_skip_evaluation = skip_evaluation;
5068 skip_evaluation = false;
5069 new_inner_args = make_tree_vec (nparms);
5070 new_args = add_outermost_template_args (args, new_inner_args);
5071 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
5076 /* Get the Ith template parameter. */
5077 parm = TREE_VEC_ELT (parms, parm_idx);
5079 if (parm == error_mark_node)
5081 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
5085 /* Calculate the next argument. */
5086 if (template_parameter_pack_p (TREE_VALUE (parm)))
5088 /* All remaining arguments will be placed in the
5089 template parameter pack PARM. */
5090 arg = coerce_template_parameter_pack (parms, parm_idx, args,
5091 inner_args, arg_idx,
5095 /* Store this argument. */
5096 if (arg == error_mark_node)
5098 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
5100 /* We are done with all of the arguments. */
5105 else if (arg_idx < nargs)
5107 arg = TREE_VEC_ELT (inner_args, arg_idx);
5109 if (arg && PACK_EXPANSION_P (arg))
5111 /* If ARG is a pack expansion, but PARM is not a
5112 template parameter pack (if it were, we would have
5113 handled it above), we're trying to expand into a
5114 fixed-length argument list. */
5115 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
5116 error ("cannot expand %<%E%> into a fixed-length "
5117 "argument list", arg);
5119 error ("cannot expand %<%T%> into a fixed-length "
5120 "argument list", arg);
5121 return error_mark_node;
5124 else if (require_all_args)
5125 /* There must be a default arg in this case. */
5126 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
5131 if (arg == error_mark_node)
5133 if (complain & tf_error)
5134 error ("template argument %d is invalid", arg_idx + 1);
5137 /* This only occurs if there was an error in the template
5138 parameter list itself (which we would already have
5139 reported) that we are trying to recover from, e.g., a class
5140 template with a parameter list such as
5141 template<typename..., typename>. */
5142 return error_mark_node;
5144 arg = convert_template_argument (TREE_VALUE (parm),
5145 arg, new_args, complain,
5148 if (arg == error_mark_node)
5150 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
5152 skip_evaluation = saved_skip_evaluation;
5155 return error_mark_node;
5157 return new_inner_args;
5160 /* Returns 1 if template args OT and NT are equivalent. */
5163 template_args_equal (tree ot, tree nt)
5168 if (TREE_CODE (nt) == TREE_VEC)
5169 /* For member templates */
5170 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
5171 else if (PACK_EXPANSION_P (ot))
5172 return PACK_EXPANSION_P (nt)
5173 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
5174 PACK_EXPANSION_PATTERN (nt));
5175 else if (TYPE_P (nt))
5176 return TYPE_P (ot) && same_type_p (ot, nt);
5177 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
5180 return cp_tree_equal (ot, nt);
5183 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
5184 of template arguments. Returns 0 otherwise. */
5187 comp_template_args (tree oldargs, tree newargs)
5191 oldargs = expand_template_argument_pack (oldargs);
5192 newargs = expand_template_argument_pack (newargs);
5194 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
5197 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
5199 tree nt = TREE_VEC_ELT (newargs, i);
5200 tree ot = TREE_VEC_ELT (oldargs, i);
5202 if (! template_args_equal (ot, nt))
5209 add_pending_template (tree d)
5211 tree ti = (TYPE_P (d)
5212 ? CLASSTYPE_TEMPLATE_INFO (d)
5213 : DECL_TEMPLATE_INFO (d));
5214 struct pending_template *pt;
5217 if (TI_PENDING_TEMPLATE_FLAG (ti))
5220 /* We are called both from instantiate_decl, where we've already had a
5221 tinst_level pushed, and instantiate_template, where we haven't.
5223 level = !current_tinst_level || current_tinst_level->decl != d;
5226 push_tinst_level (d);
5228 pt = GGC_NEW (struct pending_template);
5230 pt->tinst = current_tinst_level;
5231 if (last_pending_template)
5232 last_pending_template->next = pt;
5234 pending_templates = pt;
5236 last_pending_template = pt;
5238 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
5245 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
5246 ARGLIST. Valid choices for FNS are given in the cp-tree.def
5247 documentation for TEMPLATE_ID_EXPR. */
5250 lookup_template_function (tree fns, tree arglist)
5254 if (fns == error_mark_node || arglist == error_mark_node)
5255 return error_mark_node;
5257 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
5258 gcc_assert (fns && (is_overloaded_fn (fns)
5259 || TREE_CODE (fns) == IDENTIFIER_NODE));
5261 if (BASELINK_P (fns))
5263 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
5265 BASELINK_FUNCTIONS (fns),
5270 type = TREE_TYPE (fns);
5271 if (TREE_CODE (fns) == OVERLOAD || !type)
5272 type = unknown_type_node;
5274 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
5277 /* Within the scope of a template class S<T>, the name S gets bound
5278 (in build_self_reference) to a TYPE_DECL for the class, not a
5279 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
5280 or one of its enclosing classes, and that type is a template,
5281 return the associated TEMPLATE_DECL. Otherwise, the original
5282 DECL is returned. */
5285 maybe_get_template_decl_from_type_decl (tree decl)
5287 return (decl != NULL_TREE
5288 && TREE_CODE (decl) == TYPE_DECL
5289 && DECL_ARTIFICIAL (decl)
5290 && CLASS_TYPE_P (TREE_TYPE (decl))
5291 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
5292 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
5295 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
5296 parameters, find the desired type.
5298 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
5300 IN_DECL, if non-NULL, is the template declaration we are trying to
5303 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
5304 the class we are looking up.
5306 Issue error and warning messages under control of COMPLAIN.
5308 If the template class is really a local class in a template
5309 function, then the FUNCTION_CONTEXT is the function in which it is
5312 ??? Note that this function is currently called *twice* for each
5313 template-id: the first time from the parser, while creating the
5314 incomplete type (finish_template_type), and the second type during the
5315 real instantiation (instantiate_template_class). This is surely something
5316 that we want to avoid. It also causes some problems with argument
5317 coercion (see convert_nontype_argument for more information on this). */
5320 lookup_template_class (tree d1,
5325 tsubst_flags_t complain)
5327 tree template = NULL_TREE, parmlist;
5330 timevar_push (TV_NAME_LOOKUP);
5332 if (TREE_CODE (d1) == IDENTIFIER_NODE)
5334 tree value = innermost_non_namespace_value (d1);
5335 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
5340 push_decl_namespace (context);
5341 template = lookup_name (d1);
5342 template = maybe_get_template_decl_from_type_decl (template);
5344 pop_decl_namespace ();
5347 context = DECL_CONTEXT (template);
5349 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
5351 tree type = TREE_TYPE (d1);
5353 /* If we are declaring a constructor, say A<T>::A<T>, we will get
5354 an implicit typename for the second A. Deal with it. */
5355 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
5356 type = TREE_TYPE (type);
5358 if (CLASSTYPE_TEMPLATE_INFO (type))
5360 template = CLASSTYPE_TI_TEMPLATE (type);
5361 d1 = DECL_NAME (template);
5364 else if (TREE_CODE (d1) == ENUMERAL_TYPE
5365 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
5367 template = TYPE_TI_TEMPLATE (d1);
5368 d1 = DECL_NAME (template);
5370 else if (TREE_CODE (d1) == TEMPLATE_DECL
5371 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
5374 d1 = DECL_NAME (template);
5375 context = DECL_CONTEXT (template);
5378 /* Issue an error message if we didn't find a template. */
5381 if (complain & tf_error)
5382 error ("%qT is not a template", d1);
5383 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5386 if (TREE_CODE (template) != TEMPLATE_DECL
5387 /* Make sure it's a user visible template, if it was named by
5389 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
5390 && !PRIMARY_TEMPLATE_P (template)))
5392 if (complain & tf_error)
5394 error ("non-template type %qT used as a template", d1);
5396 error ("for template declaration %q+D", in_decl);
5398 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5401 complain &= ~tf_user;
5403 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
5405 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
5406 template arguments */
5412 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
5414 /* Consider an example where a template template parameter declared as
5416 template <class T, class U = std::allocator<T> > class TT
5418 The template parameter level of T and U are one level larger than
5419 of TT. To proper process the default argument of U, say when an
5420 instantiation `TT<int>' is seen, we need to build the full
5421 arguments containing {int} as the innermost level. Outer levels,
5422 available when not appearing as default template argument, can be
5423 obtained from the arguments of the enclosing template.
5425 Suppose that TT is later substituted with std::vector. The above
5426 instantiation is `TT<int, std::allocator<T> >' with TT at
5427 level 1, and T at level 2, while the template arguments at level 1
5428 becomes {std::vector} and the inner level 2 is {int}. */
5430 outer = DECL_CONTEXT (template);
5432 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
5433 else if (current_template_parms)
5434 /* This is an argument of the current template, so we haven't set
5435 DECL_CONTEXT yet. */
5436 outer = current_template_args ();
5439 arglist = add_to_template_args (outer, arglist);
5441 arglist2 = coerce_template_parms (parmlist, arglist, template,
5443 /*require_all_args=*/true,
5444 /*use_default_args=*/true);
5445 if (arglist2 == error_mark_node
5446 || (!uses_template_parms (arglist2)
5447 && check_instantiated_args (template, arglist2, complain)))
5448 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5450 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
5451 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
5455 tree template_type = TREE_TYPE (template);
5458 tree found = NULL_TREE;
5461 int is_partial_instantiation;
5463 gen_tmpl = most_general_template (template);
5464 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
5465 parm_depth = TMPL_PARMS_DEPTH (parmlist);
5466 arg_depth = TMPL_ARGS_DEPTH (arglist);
5468 if (arg_depth == 1 && parm_depth > 1)
5470 /* We've been given an incomplete set of template arguments.
5473 template <class T> struct S1 {
5474 template <class U> struct S2 {};
5475 template <class U> struct S2<U*> {};
5478 we will be called with an ARGLIST of `U*', but the
5479 TEMPLATE will be `template <class T> template
5480 <class U> struct S1<T>::S2'. We must fill in the missing
5483 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
5485 arg_depth = TMPL_ARGS_DEPTH (arglist);
5488 /* Now we should have enough arguments. */
5489 gcc_assert (parm_depth == arg_depth);
5491 /* From here on, we're only interested in the most general
5493 template = gen_tmpl;
5495 /* Calculate the BOUND_ARGS. These will be the args that are
5496 actually tsubst'd into the definition to create the
5500 /* We have multiple levels of arguments to coerce, at once. */
5502 int saved_depth = TMPL_ARGS_DEPTH (arglist);
5504 tree bound_args = make_tree_vec (parm_depth);
5506 for (i = saved_depth,
5507 t = DECL_TEMPLATE_PARMS (template);
5508 i > 0 && t != NULL_TREE;
5509 --i, t = TREE_CHAIN (t))
5511 tree a = coerce_template_parms (TREE_VALUE (t),
5514 /*require_all_args=*/true,
5515 /*use_default_args=*/true);
5517 /* Don't process further if one of the levels fails. */
5518 if (a == error_mark_node)
5520 /* Restore the ARGLIST to its full size. */
5521 TREE_VEC_LENGTH (arglist) = saved_depth;
5522 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5525 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
5527 /* We temporarily reduce the length of the ARGLIST so
5528 that coerce_template_parms will see only the arguments
5529 corresponding to the template parameters it is
5531 TREE_VEC_LENGTH (arglist)--;
5534 /* Restore the ARGLIST to its full size. */
5535 TREE_VEC_LENGTH (arglist) = saved_depth;
5537 arglist = bound_args;
5541 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
5542 INNERMOST_TEMPLATE_ARGS (arglist),
5545 /*require_all_args=*/true,
5546 /*use_default_args=*/true);
5548 if (arglist == error_mark_node)
5549 /* We were unable to bind the arguments. */
5550 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5552 /* In the scope of a template class, explicit references to the
5553 template class refer to the type of the template, not any
5554 instantiation of it. For example, in:
5556 template <class T> class C { void f(C<T>); }
5558 the `C<T>' is just the same as `C'. Outside of the
5559 class, however, such a reference is an instantiation. */
5560 if (comp_template_args (TYPE_TI_ARGS (template_type),
5563 found = template_type;
5565 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
5569 for (ctx = current_class_type;
5570 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
5572 ? TYPE_CONTEXT (ctx)
5573 : DECL_CONTEXT (ctx)))
5574 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
5577 /* We're not in the scope of the class, so the
5578 TEMPLATE_TYPE is not the type we want after all. */
5584 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
5586 /* If we already have this specialization, return it. */
5587 found = retrieve_specialization (template, arglist,
5588 /*class_specializations_p=*/false);
5590 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
5592 /* This type is a "partial instantiation" if any of the template
5593 arguments still involve template parameters. Note that we set
5594 IS_PARTIAL_INSTANTIATION for partial specializations as
5596 is_partial_instantiation = uses_template_parms (arglist);
5598 /* If the deduced arguments are invalid, then the binding
5600 if (!is_partial_instantiation
5601 && check_instantiated_args (template,
5602 INNERMOST_TEMPLATE_ARGS (arglist),
5604 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5606 if (!is_partial_instantiation
5607 && !PRIMARY_TEMPLATE_P (template)
5608 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
5610 found = xref_tag_from_type (TREE_TYPE (template),
5611 DECL_NAME (template),
5612 /*tag_scope=*/ts_global);
5613 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
5616 context = tsubst (DECL_CONTEXT (template), arglist,
5619 context = global_namespace;
5621 /* Create the type. */
5622 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
5624 if (!is_partial_instantiation)
5626 set_current_access_from_decl (TYPE_NAME (template_type));
5627 t = start_enum (TYPE_IDENTIFIER (template_type));
5630 /* We don't want to call start_enum for this type, since
5631 the values for the enumeration constants may involve
5632 template parameters. And, no one should be interested
5633 in the enumeration constants for such a type. */
5634 t = make_node (ENUMERAL_TYPE);
5638 t = make_aggr_type (TREE_CODE (template_type));
5639 CLASSTYPE_DECLARED_CLASS (t)
5640 = CLASSTYPE_DECLARED_CLASS (template_type);
5641 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
5642 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
5644 /* A local class. Make sure the decl gets registered properly. */
5645 if (context == current_function_decl)
5646 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
5648 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
5649 /* This instantiation is another name for the primary
5650 template type. Set the TYPE_CANONICAL field
5652 TYPE_CANONICAL (t) = template_type;
5653 else if (any_template_arguments_need_structural_equality_p (arglist))
5654 /* Some of the template arguments require structural
5655 equality testing, so this template class requires
5656 structural equality testing. */
5657 SET_TYPE_STRUCTURAL_EQUALITY (t);
5660 /* If we called start_enum or pushtag above, this information
5661 will already be set up. */
5664 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
5666 type_decl = create_implicit_typedef (DECL_NAME (template), t);
5667 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
5668 TYPE_STUB_DECL (t) = type_decl;
5669 DECL_SOURCE_LOCATION (type_decl)
5670 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
5673 type_decl = TYPE_NAME (t);
5675 TREE_PRIVATE (type_decl)
5676 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
5677 TREE_PROTECTED (type_decl)
5678 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
5679 DECL_IN_SYSTEM_HEADER (type_decl)
5680 = DECL_IN_SYSTEM_HEADER (template);
5681 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
5683 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
5684 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
5687 /* Set up the template information. We have to figure out which
5688 template is the immediate parent if this is a full
5690 if (parm_depth == 1 || is_partial_instantiation
5691 || !PRIMARY_TEMPLATE_P (template))
5692 /* This case is easy; there are no member templates involved. */
5696 /* This is a full instantiation of a member template. Look
5697 for a partial instantiation of which this is an instance. */
5699 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
5700 found; found = TREE_CHAIN (found))
5703 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
5705 /* We only want partial instantiations, here, not
5706 specializations or full instantiations. */
5707 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
5708 || !uses_template_parms (TREE_VALUE (found)))
5711 /* Temporarily reduce by one the number of levels in the
5712 ARGLIST and in FOUND so as to avoid comparing the
5713 last set of arguments. */
5714 TREE_VEC_LENGTH (arglist)--;
5715 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
5717 /* See if the arguments match. If they do, then TMPL is
5718 the partial instantiation we want. */
5719 success = comp_template_args (TREE_PURPOSE (found), arglist);
5721 /* Restore the argument vectors to their full size. */
5722 TREE_VEC_LENGTH (arglist)++;
5723 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
5734 /* There was no partial instantiation. This happens
5735 where C<T> is a member template of A<T> and it's used
5738 template <typename T> struct B { A<T>::C<int> m; };
5741 Create the partial instantiation.
5743 TREE_VEC_LENGTH (arglist)--;
5744 found = tsubst (template, arglist, complain, NULL_TREE);
5745 TREE_VEC_LENGTH (arglist)++;
5749 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
5750 DECL_TEMPLATE_INSTANTIATIONS (template)
5751 = tree_cons (arglist, t,
5752 DECL_TEMPLATE_INSTANTIATIONS (template));
5754 if (TREE_CODE (t) == ENUMERAL_TYPE
5755 && !is_partial_instantiation)
5756 /* Now that the type has been registered on the instantiations
5757 list, we set up the enumerators. Because the enumeration
5758 constants may involve the enumeration type itself, we make
5759 sure to register the type first, and then create the
5760 constants. That way, doing tsubst_expr for the enumeration
5761 constants won't result in recursive calls here; we'll find
5762 the instantiation and exit above. */
5763 tsubst_enum (template_type, t, arglist);
5765 if (is_partial_instantiation)
5766 /* If the type makes use of template parameters, the
5767 code that generates debugging information will crash. */
5768 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
5770 /* Possibly limit visibility based on template args. */
5771 TREE_PUBLIC (type_decl) = 1;
5772 determine_visibility (type_decl);
5774 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
5776 timevar_pop (TV_NAME_LOOKUP);
5783 struct pointer_set_t *visited;
5786 /* Called from for_each_template_parm via walk_tree. */
5789 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
5792 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
5793 tree_fn_t fn = pfd->fn;
5794 void *data = pfd->data;
5797 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
5798 return error_mark_node;
5800 switch (TREE_CODE (t))
5803 if (TYPE_PTRMEMFUNC_P (t))
5809 if (!TYPE_TEMPLATE_INFO (t))
5811 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
5812 fn, data, pfd->visited))
5813 return error_mark_node;
5817 if (for_each_template_parm (TYPE_MIN_VALUE (t),
5818 fn, data, pfd->visited)
5819 || for_each_template_parm (TYPE_MAX_VALUE (t),
5820 fn, data, pfd->visited))
5821 return error_mark_node;
5825 /* Since we're not going to walk subtrees, we have to do this
5827 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
5829 return error_mark_node;
5833 /* Check the return type. */
5834 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
5835 return error_mark_node;
5837 /* Check the parameter types. Since default arguments are not
5838 instantiated until they are needed, the TYPE_ARG_TYPES may
5839 contain expressions that involve template parameters. But,
5840 no-one should be looking at them yet. And, once they're
5841 instantiated, they don't contain template parameters, so
5842 there's no point in looking at them then, either. */
5846 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
5847 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
5849 return error_mark_node;
5851 /* Since we've already handled the TYPE_ARG_TYPES, we don't
5852 want walk_tree walking into them itself. */
5858 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
5860 return error_mark_node;
5865 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
5866 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
5868 return error_mark_node;
5873 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
5874 && for_each_template_parm (DECL_INITIAL (t), fn, data,
5876 return error_mark_node;
5877 if (DECL_CONTEXT (t)
5878 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
5880 return error_mark_node;
5883 case BOUND_TEMPLATE_TEMPLATE_PARM:
5884 /* Record template parameters such as `T' inside `TT<T>'. */
5885 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
5886 return error_mark_node;
5889 case TEMPLATE_TEMPLATE_PARM:
5890 case TEMPLATE_TYPE_PARM:
5891 case TEMPLATE_PARM_INDEX:
5892 if (fn && (*fn)(t, data))
5893 return error_mark_node;
5895 return error_mark_node;
5899 /* A template template parameter is encountered. */
5900 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
5901 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
5902 return error_mark_node;
5904 /* Already substituted template template parameter */
5910 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
5911 data, pfd->visited))
5912 return error_mark_node;
5916 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
5917 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
5918 (TREE_TYPE (t)), fn, data,
5920 return error_mark_node;
5925 /* If there's no type, then this thing must be some expression
5926 involving template parameters. */
5927 if (!fn && !TREE_TYPE (t))
5928 return error_mark_node;
5933 case REINTERPRET_CAST_EXPR:
5934 case CONST_CAST_EXPR:
5935 case STATIC_CAST_EXPR:
5936 case DYNAMIC_CAST_EXPR:
5940 case PSEUDO_DTOR_EXPR:
5942 return error_mark_node;
5949 /* We didn't find any template parameters we liked. */
5953 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
5954 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
5955 call FN with the parameter and the DATA.
5956 If FN returns nonzero, the iteration is terminated, and
5957 for_each_template_parm returns 1. Otherwise, the iteration
5958 continues. If FN never returns a nonzero value, the value
5959 returned by for_each_template_parm is 0. If FN is NULL, it is
5960 considered to be the function which always returns 1. */
5963 for_each_template_parm (tree t, tree_fn_t fn, void* data,
5964 struct pointer_set_t *visited)
5966 struct pair_fn_data pfd;
5973 /* Walk the tree. (Conceptually, we would like to walk without
5974 duplicates, but for_each_template_parm_r recursively calls
5975 for_each_template_parm, so we would need to reorganize a fair
5976 bit to use walk_tree_without_duplicates, so we keep our own
5979 pfd.visited = visited;
5981 pfd.visited = pointer_set_create ();
5982 result = cp_walk_tree (&t,
5983 for_each_template_parm_r,
5985 pfd.visited) != NULL_TREE;
5990 pointer_set_destroy (pfd.visited);
5997 /* Returns true if T depends on any template parameter. */
6000 uses_template_parms (tree t)
6003 int saved_processing_template_decl;
6005 saved_processing_template_decl = processing_template_decl;
6006 if (!saved_processing_template_decl)
6007 processing_template_decl = 1;
6009 dependent_p = dependent_type_p (t);
6010 else if (TREE_CODE (t) == TREE_VEC)
6011 dependent_p = any_dependent_template_arguments_p (t);
6012 else if (TREE_CODE (t) == TREE_LIST)
6013 dependent_p = (uses_template_parms (TREE_VALUE (t))
6014 || uses_template_parms (TREE_CHAIN (t)));
6015 else if (TREE_CODE (t) == TYPE_DECL)
6016 dependent_p = dependent_type_p (TREE_TYPE (t));
6019 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
6020 || TREE_CODE (t) == OVERLOAD
6021 || TREE_CODE (t) == BASELINK
6022 || TREE_CODE (t) == IDENTIFIER_NODE
6023 || TREE_CODE (t) == TRAIT_EXPR
6024 || CONSTANT_CLASS_P (t))
6025 dependent_p = (type_dependent_expression_p (t)
6026 || value_dependent_expression_p (t));
6029 gcc_assert (t == error_mark_node);
6030 dependent_p = false;
6033 processing_template_decl = saved_processing_template_decl;
6038 /* Returns true if T depends on any template parameter with level LEVEL. */
6041 uses_template_parms_level (tree t, int level)
6043 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
6046 static int tinst_depth;
6047 extern int max_tinst_depth;
6048 #ifdef GATHER_STATISTICS
6051 static int tinst_level_tick;
6052 static int last_template_error_tick;
6054 /* We're starting to instantiate D; record the template instantiation context
6055 for diagnostics and to restore it later. */
6058 push_tinst_level (tree d)
6060 struct tinst_level *new;
6062 if (tinst_depth >= max_tinst_depth)
6064 /* If the instantiation in question still has unbound template parms,
6065 we don't really care if we can't instantiate it, so just return.
6066 This happens with base instantiation for implicit `typename'. */
6067 if (uses_template_parms (d))
6070 last_template_error_tick = tinst_level_tick;
6071 error ("template instantiation depth exceeds maximum of %d (use "
6072 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
6073 max_tinst_depth, d);
6075 print_instantiation_context ();
6080 new = GGC_NEW (struct tinst_level);
6082 new->locus = input_location;
6083 new->in_system_header_p = in_system_header;
6084 new->next = current_tinst_level;
6085 current_tinst_level = new;
6088 #ifdef GATHER_STATISTICS
6089 if (tinst_depth > depth_reached)
6090 depth_reached = tinst_depth;
6097 /* We're done instantiating this template; return to the instantiation
6101 pop_tinst_level (void)
6103 /* Restore the filename and line number stashed away when we started
6104 this instantiation. */
6105 input_location = current_tinst_level->locus;
6106 in_system_header = current_tinst_level->in_system_header_p;
6107 current_tinst_level = current_tinst_level->next;
6112 /* We're instantiating a deferred template; restore the template
6113 instantiation context in which the instantiation was requested, which
6114 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
6117 reopen_tinst_level (struct tinst_level *level)
6119 struct tinst_level *t;
6122 for (t = level; t; t = t->next)
6125 current_tinst_level = level;
6130 /* Returns the TINST_LEVEL which gives the original instantiation
6133 struct tinst_level *
6134 outermost_tinst_level (void)
6136 struct tinst_level *level = current_tinst_level;
6139 level = level->next;
6143 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
6144 vector of template arguments, as for tsubst.
6146 Returns an appropriate tsubst'd friend declaration. */
6149 tsubst_friend_function (tree decl, tree args)
6153 if (TREE_CODE (decl) == FUNCTION_DECL
6154 && DECL_TEMPLATE_INSTANTIATION (decl)
6155 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
6156 /* This was a friend declared with an explicit template
6157 argument list, e.g.:
6161 to indicate that f was a template instantiation, not a new
6162 function declaration. Now, we have to figure out what
6163 instantiation of what template. */
6165 tree template_id, arglist, fns;
6168 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
6170 /* Friend functions are looked up in the containing namespace scope.
6171 We must enter that scope, to avoid finding member functions of the
6172 current cless with same name. */
6173 push_nested_namespace (ns);
6174 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
6175 tf_warning_or_error, NULL_TREE,
6176 /*integral_constant_expression_p=*/false);
6177 pop_nested_namespace (ns);
6178 arglist = tsubst (DECL_TI_ARGS (decl), args,
6179 tf_warning_or_error, NULL_TREE);
6180 template_id = lookup_template_function (fns, arglist);
6182 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6183 tmpl = determine_specialization (template_id, new_friend,
6185 /*need_member_template=*/0,
6186 TREE_VEC_LENGTH (args),
6188 return instantiate_template (tmpl, new_args, tf_error);
6191 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6193 /* The NEW_FRIEND will look like an instantiation, to the
6194 compiler, but is not an instantiation from the point of view of
6195 the language. For example, we might have had:
6197 template <class T> struct S {
6198 template <class U> friend void f(T, U);
6201 Then, in S<int>, template <class U> void f(int, U) is not an
6202 instantiation of anything. */
6203 if (new_friend == error_mark_node)
6204 return error_mark_node;
6206 DECL_USE_TEMPLATE (new_friend) = 0;
6207 if (TREE_CODE (decl) == TEMPLATE_DECL)
6209 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
6210 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
6211 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
6214 /* The mangled name for the NEW_FRIEND is incorrect. The function
6215 is not a template instantiation and should not be mangled like
6216 one. Therefore, we forget the mangling here; we'll recompute it
6217 later if we need it. */
6218 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
6220 SET_DECL_RTL (new_friend, NULL_RTX);
6221 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
6224 if (DECL_NAMESPACE_SCOPE_P (new_friend))
6227 tree new_friend_template_info;
6228 tree new_friend_result_template_info;
6230 int new_friend_is_defn;
6232 /* We must save some information from NEW_FRIEND before calling
6233 duplicate decls since that function will free NEW_FRIEND if
6235 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
6236 new_friend_is_defn =
6237 (DECL_INITIAL (DECL_TEMPLATE_RESULT
6238 (template_for_substitution (new_friend)))
6240 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
6242 /* This declaration is a `primary' template. */
6243 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
6245 new_friend_result_template_info
6246 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
6249 new_friend_result_template_info = NULL_TREE;
6251 /* Make the init_value nonzero so pushdecl knows this is a defn. */
6252 if (new_friend_is_defn)
6253 DECL_INITIAL (new_friend) = error_mark_node;
6255 /* Inside pushdecl_namespace_level, we will push into the
6256 current namespace. However, the friend function should go
6257 into the namespace of the template. */
6258 ns = decl_namespace_context (new_friend);
6259 push_nested_namespace (ns);
6260 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
6261 pop_nested_namespace (ns);
6263 if (old_decl == error_mark_node)
6264 return error_mark_node;
6266 if (old_decl != new_friend)
6268 /* This new friend declaration matched an existing
6269 declaration. For example, given:
6271 template <class T> void f(T);
6272 template <class U> class C {
6273 template <class T> friend void f(T) {}
6276 the friend declaration actually provides the definition
6277 of `f', once C has been instantiated for some type. So,
6278 old_decl will be the out-of-class template declaration,
6279 while new_friend is the in-class definition.
6281 But, if `f' was called before this point, the
6282 instantiation of `f' will have DECL_TI_ARGS corresponding
6283 to `T' but not to `U', references to which might appear
6284 in the definition of `f'. Previously, the most general
6285 template for an instantiation of `f' was the out-of-class
6286 version; now it is the in-class version. Therefore, we
6287 run through all specialization of `f', adding to their
6288 DECL_TI_ARGS appropriately. In particular, they need a
6289 new set of outer arguments, corresponding to the
6290 arguments for this class instantiation.
6292 The same situation can arise with something like this:
6295 template <class T> class C {
6299 when `C<int>' is instantiated. Now, `f(int)' is defined
6302 if (!new_friend_is_defn)
6303 /* On the other hand, if the in-class declaration does
6304 *not* provide a definition, then we don't want to alter
6305 existing definitions. We can just leave everything
6310 /* Overwrite whatever template info was there before, if
6311 any, with the new template information pertaining to
6313 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
6315 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
6316 reregister_specialization (new_friend,
6317 most_general_template (old_decl),
6322 tree new_friend_args;
6324 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
6325 = new_friend_result_template_info;
6327 new_friend_args = TI_ARGS (new_friend_template_info);
6328 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
6332 tree spec = TREE_VALUE (t);
6335 = add_outermost_template_args (new_friend_args,
6336 DECL_TI_ARGS (spec));
6339 /* Now, since specializations are always supposed to
6340 hang off of the most general template, we must move
6342 t = most_general_template (old_decl);
6345 DECL_TEMPLATE_SPECIALIZATIONS (t)
6346 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
6347 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
6348 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
6353 /* The information from NEW_FRIEND has been merged into OLD_DECL
6354 by duplicate_decls. */
6355 new_friend = old_decl;
6360 tree context = DECL_CONTEXT (new_friend);
6364 template <class T> class C {
6365 template <class U> friend void C1<U>::f (); // case 1
6366 friend void C2<T>::f (); // case 2
6368 we only need to make sure CONTEXT is a complete type for
6369 case 2. To distinguish between the two cases, we note that
6370 CONTEXT of case 1 remains dependent type after tsubst while
6371 this isn't true for case 2. */
6372 ++processing_template_decl;
6373 dependent_p = dependent_type_p (context);
6374 --processing_template_decl;
6377 && !complete_type_or_else (context, NULL_TREE))
6378 return error_mark_node;
6380 if (COMPLETE_TYPE_P (context))
6382 /* Check to see that the declaration is really present, and,
6383 possibly obtain an improved declaration. */
6384 tree fn = check_classfn (context,
6385 new_friend, NULL_TREE);
6395 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
6396 template arguments, as for tsubst.
6398 Returns an appropriate tsubst'd friend type or error_mark_node on
6402 tsubst_friend_class (tree friend_tmpl, tree args)
6408 context = DECL_CONTEXT (friend_tmpl);
6412 if (TREE_CODE (context) == NAMESPACE_DECL)
6413 push_nested_namespace (context);
6415 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
6418 /* Look for a class template declaration. We look for hidden names
6419 because two friend declarations of the same template are the
6420 same. For example, in:
6423 template <typename> friend class F;
6425 template <typename> struct B {
6426 template <typename> friend class F;
6429 both F templates are the same. */
6430 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
6431 /*block_p=*/true, 0,
6432 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
6434 /* But, if we don't find one, it might be because we're in a
6435 situation like this:
6443 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
6444 for `S<int>', not the TEMPLATE_DECL. */
6445 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
6447 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
6448 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
6451 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
6453 /* The friend template has already been declared. Just
6454 check to see that the declarations match, and install any new
6455 default parameters. We must tsubst the default parameters,
6456 of course. We only need the innermost template parameters
6457 because that is all that redeclare_class_template will look
6459 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
6460 > TMPL_ARGS_DEPTH (args))
6463 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
6464 args, tf_warning_or_error);
6465 redeclare_class_template (TREE_TYPE (tmpl), parms);
6468 friend_type = TREE_TYPE (tmpl);
6472 /* The friend template has not already been declared. In this
6473 case, the instantiation of the template class will cause the
6474 injection of this template into the global scope. */
6475 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
6476 if (tmpl == error_mark_node)
6477 return error_mark_node;
6479 /* The new TMPL is not an instantiation of anything, so we
6480 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
6481 the new type because that is supposed to be the corresponding
6482 template decl, i.e., TMPL. */
6483 DECL_USE_TEMPLATE (tmpl) = 0;
6484 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
6485 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
6486 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
6487 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
6489 /* Inject this template into the global scope. */
6490 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
6495 if (TREE_CODE (context) == NAMESPACE_DECL)
6496 pop_nested_namespace (context);
6498 pop_nested_class ();
6504 /* Returns zero if TYPE cannot be completed later due to circularity.
6505 Otherwise returns one. */
6508 can_complete_type_without_circularity (tree type)
6510 if (type == NULL_TREE || type == error_mark_node)
6512 else if (COMPLETE_TYPE_P (type))
6514 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
6515 return can_complete_type_without_circularity (TREE_TYPE (type));
6516 else if (CLASS_TYPE_P (type)
6517 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
6523 /* Apply any attributes which had to be deferred until instantiation
6524 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
6525 ARGS, COMPLAIN, IN_DECL are as tsubst. */
6528 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
6529 tree args, tsubst_flags_t complain, tree in_decl)
6531 tree last_dep = NULL_TREE;
6535 for (t = attributes; t; t = TREE_CHAIN (t))
6536 if (ATTR_IS_DEPENDENT (t))
6539 attributes = copy_list (attributes);
6543 if (DECL_P (*decl_p))
6544 p = &DECL_ATTRIBUTES (*decl_p);
6546 p = &TYPE_ATTRIBUTES (*decl_p);
6550 tree late_attrs = NULL_TREE;
6551 tree *q = &late_attrs;
6553 for (*p = attributes; *p; )
6556 if (ATTR_IS_DEPENDENT (t))
6558 *p = TREE_CHAIN (t);
6559 TREE_CHAIN (t) = NULL_TREE;
6561 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
6562 /*integral_constant_expression_p=*/false);
6564 q = &TREE_CHAIN (t);
6567 p = &TREE_CHAIN (t);
6570 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
6575 instantiate_class_template (tree type)
6577 tree template, args, pattern, t, member;
6582 if (type == error_mark_node)
6583 return error_mark_node;
6585 if (TYPE_BEING_DEFINED (type)
6586 || COMPLETE_TYPE_P (type)
6587 || dependent_type_p (type))
6590 /* Figure out which template is being instantiated. */
6591 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
6592 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
6594 /* Determine what specialization of the original template to
6596 t = most_specialized_class (type, template);
6597 if (t == error_mark_node)
6599 TYPE_BEING_DEFINED (type) = 1;
6600 return error_mark_node;
6604 /* This TYPE is actually an instantiation of a partial
6605 specialization. We replace the innermost set of ARGS with
6606 the arguments appropriate for substitution. For example,
6609 template <class T> struct S {};
6610 template <class T> struct S<T*> {};
6612 and supposing that we are instantiating S<int*>, ARGS will
6613 presently be {int*} -- but we need {int}. */
6614 pattern = TREE_TYPE (t);
6615 args = TREE_PURPOSE (t);
6619 pattern = TREE_TYPE (template);
6620 args = CLASSTYPE_TI_ARGS (type);
6623 /* If the template we're instantiating is incomplete, then clearly
6624 there's nothing we can do. */
6625 if (!COMPLETE_TYPE_P (pattern))
6628 /* If we've recursively instantiated too many templates, stop. */
6629 if (! push_tinst_level (type))
6632 /* Now we're really doing the instantiation. Mark the type as in
6633 the process of being defined. */
6634 TYPE_BEING_DEFINED (type) = 1;
6636 /* We may be in the middle of deferred access check. Disable
6638 push_deferring_access_checks (dk_no_deferred);
6640 push_to_top_level ();
6642 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
6644 /* Set the input location to the template definition. This is needed
6645 if tsubsting causes an error. */
6646 typedecl = TYPE_MAIN_DECL (type);
6647 input_location = DECL_SOURCE_LOCATION (typedecl);
6648 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
6650 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
6651 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
6652 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
6653 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
6654 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
6655 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
6656 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
6657 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
6658 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
6659 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
6660 TYPE_PACKED (type) = TYPE_PACKED (pattern);
6661 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
6662 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
6663 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
6664 if (ANON_AGGR_TYPE_P (pattern))
6665 SET_ANON_AGGR_TYPE_P (type);
6666 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
6668 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
6669 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
6672 pbinfo = TYPE_BINFO (pattern);
6674 /* We should never instantiate a nested class before its enclosing
6675 class; we need to look up the nested class by name before we can
6676 instantiate it, and that lookup should instantiate the enclosing
6678 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
6679 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
6680 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
6682 base_list = NULL_TREE;
6683 if (BINFO_N_BASE_BINFOS (pbinfo))
6686 tree context = TYPE_CONTEXT (type);
6690 /* We must enter the scope containing the type, as that is where
6691 the accessibility of types named in dependent bases are
6693 pushed_scope = push_scope (context ? context : global_namespace);
6695 /* Substitute into each of the bases to determine the actual
6697 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
6700 tree access = BINFO_BASE_ACCESS (pbinfo, i);
6701 tree expanded_bases = NULL_TREE;
6704 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
6707 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
6708 args, tf_error, NULL_TREE);
6709 if (expanded_bases == error_mark_node)
6712 len = TREE_VEC_LENGTH (expanded_bases);
6715 for (idx = 0; idx < len; idx++)
6718 /* Extract the already-expanded base class. */
6719 base = TREE_VEC_ELT (expanded_bases, idx);
6721 /* Substitute to figure out the base class. */
6722 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
6725 if (base == error_mark_node)
6728 base_list = tree_cons (access, base, base_list);
6729 if (BINFO_VIRTUAL_P (pbase_binfo))
6730 TREE_TYPE (base_list) = integer_type_node;
6734 /* The list is now in reverse order; correct that. */
6735 base_list = nreverse (base_list);
6738 pop_scope (pushed_scope);
6740 /* Now call xref_basetypes to set up all the base-class
6742 xref_basetypes (type, base_list);
6744 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
6745 (int) ATTR_FLAG_TYPE_IN_PLACE,
6746 args, tf_error, NULL_TREE);
6748 /* Now that our base classes are set up, enter the scope of the
6749 class, so that name lookups into base classes, etc. will work
6750 correctly. This is precisely analogous to what we do in
6751 begin_class_definition when defining an ordinary non-template
6752 class, except we also need to push the enclosing classes. */
6753 push_nested_class (type);
6755 /* Now members are processed in the order of declaration. */
6756 for (member = CLASSTYPE_DECL_LIST (pattern);
6757 member; member = TREE_CHAIN (member))
6759 tree t = TREE_VALUE (member);
6761 if (TREE_PURPOSE (member))
6765 /* Build new CLASSTYPE_NESTED_UTDS. */
6768 bool class_template_p;
6770 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
6771 && TYPE_LANG_SPECIFIC (t)
6772 && CLASSTYPE_IS_TEMPLATE (t));
6773 /* If the member is a class template, then -- even after
6774 substitution -- there may be dependent types in the
6775 template argument list for the class. We increment
6776 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
6777 that function will assume that no types are dependent
6778 when outside of a template. */
6779 if (class_template_p)
6780 ++processing_template_decl;
6781 newtag = tsubst (t, args, tf_error, NULL_TREE);
6782 if (class_template_p)
6783 --processing_template_decl;
6784 if (newtag == error_mark_node)
6787 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
6789 tree name = TYPE_IDENTIFIER (t);
6791 if (class_template_p)
6792 /* Unfortunately, lookup_template_class sets
6793 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
6794 instantiation (i.e., for the type of a member
6795 template class nested within a template class.)
6796 This behavior is required for
6797 maybe_process_partial_specialization to work
6798 correctly, but is not accurate in this case;
6799 the TAG is not an instantiation of anything.
6800 (The corresponding TEMPLATE_DECL is an
6801 instantiation, but the TYPE is not.) */
6802 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
6804 /* Now, we call pushtag to put this NEWTAG into the scope of
6805 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
6806 pushtag calling push_template_decl. We don't have to do
6807 this for enums because it will already have been done in
6810 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
6811 pushtag (name, newtag, /*tag_scope=*/ts_current);
6814 else if (TREE_CODE (t) == FUNCTION_DECL
6815 || DECL_FUNCTION_TEMPLATE_P (t))
6817 /* Build new TYPE_METHODS. */
6820 if (TREE_CODE (t) == TEMPLATE_DECL)
6821 ++processing_template_decl;
6822 r = tsubst (t, args, tf_error, NULL_TREE);
6823 if (TREE_CODE (t) == TEMPLATE_DECL)
6824 --processing_template_decl;
6825 set_current_access_from_decl (r);
6826 finish_member_declaration (r);
6830 /* Build new TYPE_FIELDS. */
6831 if (TREE_CODE (t) == STATIC_ASSERT)
6834 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
6835 tf_warning_or_error, NULL_TREE,
6836 /*integral_constant_expression_p=*/true);
6837 finish_static_assert (condition,
6838 STATIC_ASSERT_MESSAGE (t),
6839 STATIC_ASSERT_SOURCE_LOCATION (t),
6842 else if (TREE_CODE (t) != CONST_DECL)
6846 /* The the file and line for this declaration, to
6847 assist in error message reporting. Since we
6848 called push_tinst_level above, we don't need to
6850 input_location = DECL_SOURCE_LOCATION (t);
6852 if (TREE_CODE (t) == TEMPLATE_DECL)
6853 ++processing_template_decl;
6854 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
6855 if (TREE_CODE (t) == TEMPLATE_DECL)
6856 --processing_template_decl;
6857 if (TREE_CODE (r) == VAR_DECL)
6861 [t]he initialization (and any associated
6862 side-effects) of a static data member does
6863 not occur unless the static data member is
6864 itself used in a way that requires the
6865 definition of the static data member to
6868 Therefore, we do not substitute into the
6869 initialized for the static data member here. */
6870 finish_static_data_member_decl
6873 /*init_const_expr_p=*/false,
6874 /*asmspec_tree=*/NULL_TREE,
6876 if (DECL_INITIALIZED_IN_CLASS_P (r))
6877 check_static_variable_definition (r, TREE_TYPE (r));
6879 else if (TREE_CODE (r) == FIELD_DECL)
6881 /* Determine whether R has a valid type and can be
6882 completed later. If R is invalid, then it is
6883 replaced by error_mark_node so that it will not be
6884 added to TYPE_FIELDS. */
6885 tree rtype = TREE_TYPE (r);
6886 if (can_complete_type_without_circularity (rtype))
6887 complete_type (rtype);
6889 if (!COMPLETE_TYPE_P (rtype))
6891 cxx_incomplete_type_error (r, rtype);
6892 r = error_mark_node;
6896 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
6897 such a thing will already have been added to the field
6898 list by tsubst_enum in finish_member_declaration in the
6899 CLASSTYPE_NESTED_UTDS case above. */
6900 if (!(TREE_CODE (r) == TYPE_DECL
6901 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
6902 && DECL_ARTIFICIAL (r)))
6904 set_current_access_from_decl (r);
6905 finish_member_declaration (r);
6912 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
6914 /* Build new CLASSTYPE_FRIEND_CLASSES. */
6916 tree friend_type = t;
6917 bool adjust_processing_template_decl = false;
6919 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
6921 /* template <class T> friend class C; */
6922 friend_type = tsubst_friend_class (friend_type, args);
6923 adjust_processing_template_decl = true;
6925 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
6927 /* template <class T> friend class C::D; */
6928 friend_type = tsubst (friend_type, args,
6929 tf_warning_or_error, NULL_TREE);
6930 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
6931 friend_type = TREE_TYPE (friend_type);
6932 adjust_processing_template_decl = true;
6934 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
6936 /* This could be either
6940 when dependent_type_p is false or
6942 template <class U> friend class T::C;
6945 friend_type = tsubst (friend_type, args,
6946 tf_warning_or_error, NULL_TREE);
6947 /* Bump processing_template_decl for correct
6948 dependent_type_p calculation. */
6949 ++processing_template_decl;
6950 if (dependent_type_p (friend_type))
6951 adjust_processing_template_decl = true;
6952 --processing_template_decl;
6954 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
6955 && hidden_name_p (TYPE_NAME (friend_type)))
6959 where C hasn't been declared yet. Let's lookup name
6960 from namespace scope directly, bypassing any name that
6961 come from dependent base class. */
6962 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
6964 /* The call to xref_tag_from_type does injection for friend
6966 push_nested_namespace (ns);
6968 xref_tag_from_type (friend_type, NULL_TREE,
6969 /*tag_scope=*/ts_current);
6970 pop_nested_namespace (ns);
6972 else if (uses_template_parms (friend_type))
6973 /* friend class C<T>; */
6974 friend_type = tsubst (friend_type, args,
6975 tf_warning_or_error, NULL_TREE);
6980 where C is already declared or
6982 friend class C<int>;
6984 We don't have to do anything in these cases. */
6986 if (adjust_processing_template_decl)
6987 /* Trick make_friend_class into realizing that the friend
6988 we're adding is a template, not an ordinary class. It's
6989 important that we use make_friend_class since it will
6990 perform some error-checking and output cross-reference
6992 ++processing_template_decl;
6994 if (friend_type != error_mark_node)
6995 make_friend_class (type, friend_type, /*complain=*/false);
6997 if (adjust_processing_template_decl)
6998 --processing_template_decl;
7002 /* Build new DECL_FRIENDLIST. */
7005 /* The the file and line for this declaration, to
7006 assist in error message reporting. Since we
7007 called push_tinst_level above, we don't need to
7009 input_location = DECL_SOURCE_LOCATION (t);
7011 if (TREE_CODE (t) == TEMPLATE_DECL)
7013 ++processing_template_decl;
7014 push_deferring_access_checks (dk_no_check);
7017 r = tsubst_friend_function (t, args);
7018 add_friend (type, r, /*complain=*/false);
7019 if (TREE_CODE (t) == TEMPLATE_DECL)
7021 pop_deferring_access_checks ();
7022 --processing_template_decl;
7028 /* Set the file and line number information to whatever is given for
7029 the class itself. This puts error messages involving generated
7030 implicit functions at a predictable point, and the same point
7031 that would be used for non-template classes. */
7032 input_location = DECL_SOURCE_LOCATION (typedecl);
7034 unreverse_member_declarations (type);
7035 finish_struct_1 (type);
7036 TYPE_BEING_DEFINED (type) = 0;
7038 /* Now that the class is complete, instantiate default arguments for
7039 any member functions. We don't do this earlier because the
7040 default arguments may reference members of the class. */
7041 if (!PRIMARY_TEMPLATE_P (template))
7042 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
7043 if (TREE_CODE (t) == FUNCTION_DECL
7044 /* Implicitly generated member functions will not have template
7045 information; they are not instantiations, but instead are
7046 created "fresh" for each instantiation. */
7047 && DECL_TEMPLATE_INFO (t))
7048 tsubst_default_arguments (t);
7050 pop_nested_class ();
7051 pop_from_top_level ();
7052 pop_deferring_access_checks ();
7055 /* The vtable for a template class can be emitted in any translation
7056 unit in which the class is instantiated. When there is no key
7057 method, however, finish_struct_1 will already have added TYPE to
7058 the keyed_classes list. */
7059 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
7060 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
7066 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7072 else if (TYPE_P (t))
7073 r = tsubst (t, args, complain, in_decl);
7076 r = tsubst_expr (t, args, complain, in_decl,
7077 /*integral_constant_expression_p=*/true);
7078 r = fold_non_dependent_expr (r);
7083 /* Substitute ARGS into T, which is an pack expansion
7084 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
7085 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
7086 (if only a partial substitution could be performed) or
7087 ERROR_MARK_NODE if there was an error. */
7089 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
7093 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
7094 tree first_arg_pack; int i, len = -1;
7098 gcc_assert (PACK_EXPANSION_P (t));
7099 pattern = PACK_EXPANSION_PATTERN (t);
7101 /* Determine the argument packs that will instantiate the parameter
7102 packs used in the expansion expression. While we're at it,
7103 compute the number of arguments to be expanded and make sure it
7105 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
7106 pack = TREE_CHAIN (pack))
7108 tree parm_pack = TREE_VALUE (pack);
7109 tree arg_pack = NULL_TREE;
7110 tree orig_arg = NULL_TREE;
7112 if (TREE_CODE (parm_pack) == PARM_DECL)
7114 if (local_specializations)
7115 arg_pack = retrieve_local_specialization (parm_pack);
7119 int level, idx, levels;
7120 template_parm_level_and_index (parm_pack, &level, &idx);
7122 levels = TMPL_ARGS_DEPTH (args);
7123 if (level <= levels)
7124 arg_pack = TMPL_ARG (args, level, idx);
7127 orig_arg = arg_pack;
7128 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
7129 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
7131 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
7132 /* This can only happen if we forget to expand an argument
7133 pack somewhere else. Just return an error, silently. */
7135 result = make_tree_vec (1);
7136 TREE_VEC_ELT (result, 0) = error_mark_node;
7141 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
7142 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
7144 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
7145 tree pattern = PACK_EXPANSION_PATTERN (expansion);
7146 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
7147 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
7148 /* The argument pack that the parameter maps to is just an
7149 expansion of the parameter itself, such as one would
7150 find in the implicit typedef of a class inside the
7151 class itself. Consider this parameter "unsubstituted",
7152 so that we will maintain the outer pack expansion. */
7153 arg_pack = NULL_TREE;
7159 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
7161 /* It's all-or-nothing with incomplete argument packs. */
7162 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7163 return error_mark_node;
7165 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7171 first_arg_pack = arg_pack;
7173 else if (len != my_len)
7175 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
7176 error ("mismatched argument pack lengths while expanding "
7180 error ("mismatched argument pack lengths while expanding "
7183 return error_mark_node;
7186 /* Keep track of the parameter packs and their corresponding
7188 packs = tree_cons (parm_pack, arg_pack, packs);
7189 TREE_TYPE (packs) = orig_arg;
7192 /* We can't substitute for this parameter pack. */
7193 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
7195 unsubstituted_packs);
7198 /* We cannot expand this expansion expression, because we don't have
7199 all of the argument packs we need. Substitute into the pattern
7200 and return a PACK_EXPANSION_*. The caller will need to deal with
7202 if (unsubstituted_packs)
7203 return make_pack_expansion (tsubst (pattern, args, complain,
7206 /* We could not find any argument packs that work. */
7208 return error_mark_node;
7210 /* For each argument in each argument pack, substitute into the
7212 result = make_tree_vec (len + incomplete);
7213 for (i = 0; i < len + incomplete; ++i)
7215 /* For parameter pack, change the substitution of the parameter
7216 pack to the ith argument in its argument pack, then expand
7218 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7220 tree parm = TREE_PURPOSE (pack);
7222 if (TREE_CODE (parm) == PARM_DECL)
7224 /* Select the Ith argument from the pack. */
7225 tree arg = make_node (ARGUMENT_PACK_SELECT);
7226 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
7227 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
7229 register_local_specialization (arg, parm);
7235 template_parm_level_and_index (parm, &level, &idx);
7239 /* Select the Ith argument from the pack. */
7240 value = make_node (ARGUMENT_PACK_SELECT);
7241 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
7242 ARGUMENT_PACK_SELECT_INDEX (value) = i;
7245 /* Update the corresponding argument. */
7246 TMPL_ARG (args, level, idx) = value;
7250 /* Substitute into the PATTERN with the altered arguments. */
7251 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
7252 TREE_VEC_ELT (result, i) =
7253 tsubst_expr (pattern, args, complain, in_decl,
7254 /*integral_constant_expression_p=*/false);
7256 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
7259 /* When we have incomplete argument packs, the last "expanded"
7260 result is itself a pack expansion, which allows us
7261 to deduce more arguments. */
7262 TREE_VEC_ELT (result, i) =
7263 make_pack_expansion (TREE_VEC_ELT (result, i));
7265 if (TREE_VEC_ELT (result, i) == error_mark_node)
7267 result = error_mark_node;
7272 /* Update ARGS to restore the substitution from parameter packs to
7273 their argument packs. */
7274 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7276 tree parm = TREE_PURPOSE (pack);
7278 if (TREE_CODE (parm) == PARM_DECL)
7279 register_local_specialization (TREE_TYPE (pack), parm);
7283 template_parm_level_and_index (parm, &level, &idx);
7285 /* Update the corresponding argument. */
7286 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
7287 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
7290 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
7297 /* Substitute ARGS into the vector or list of template arguments T. */
7300 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7303 int len = TREE_VEC_LENGTH (t);
7304 int need_new = 0, i, expanded_len_adjust = 0, out;
7305 tree *elts = (tree *) alloca (len * sizeof (tree));
7307 for (i = 0; i < len; i++)
7309 tree orig_arg = TREE_VEC_ELT (t, i);
7312 if (TREE_CODE (orig_arg) == TREE_VEC)
7313 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
7314 else if (PACK_EXPANSION_P (orig_arg))
7316 /* Substitute into an expansion expression. */
7317 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
7319 if (TREE_CODE (new_arg) == TREE_VEC)
7320 /* Add to the expanded length adjustment the number of
7321 expanded arguments. We subtract one from this
7322 measurement, because the argument pack expression
7323 itself is already counted as 1 in
7324 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
7325 the argument pack is empty. */
7326 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
7328 else if (ARGUMENT_PACK_P (orig_arg))
7330 /* Substitute into each of the arguments. */
7331 new_arg = make_node (TREE_CODE (orig_arg));
7333 SET_ARGUMENT_PACK_ARGS (
7335 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
7336 args, complain, in_decl));
7338 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
7339 new_arg = error_mark_node;
7341 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
7342 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
7344 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
7346 if (TREE_TYPE (new_arg) == error_mark_node)
7347 new_arg = error_mark_node;
7351 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
7353 if (new_arg == error_mark_node)
7354 return error_mark_node;
7357 if (new_arg != orig_arg)
7364 /* Make space for the expanded arguments coming from template
7366 t = make_tree_vec (len + expanded_len_adjust);
7367 for (i = 0, out = 0; i < len; i++)
7369 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
7370 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
7371 && TREE_CODE (elts[i]) == TREE_VEC)
7375 /* Now expand the template argument pack "in place". */
7376 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
7377 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
7381 TREE_VEC_ELT (t, out) = elts[i];
7389 /* Return the result of substituting ARGS into the template parameters
7390 given by PARMS. If there are m levels of ARGS and m + n levels of
7391 PARMS, then the result will contain n levels of PARMS. For
7392 example, if PARMS is `template <class T> template <class U>
7393 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
7394 result will be `template <int*, double, class V>'. */
7397 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
7402 /* When substituting into a template, we must set
7403 PROCESSING_TEMPLATE_DECL as the template parameters may be
7404 dependent if they are based on one-another, and the dependency
7405 predicates are short-circuit outside of templates. */
7406 ++processing_template_decl;
7408 for (new_parms = &r;
7409 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
7410 new_parms = &(TREE_CHAIN (*new_parms)),
7411 parms = TREE_CHAIN (parms))
7414 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
7417 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
7423 if (parms == error_mark_node)
7426 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
7428 if (tuple == error_mark_node)
7431 default_value = TREE_PURPOSE (tuple);
7432 parm_decl = TREE_VALUE (tuple);
7434 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
7435 if (TREE_CODE (parm_decl) == PARM_DECL
7436 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
7437 parm_decl = error_mark_node;
7438 default_value = tsubst_template_arg (default_value, args,
7439 complain, NULL_TREE);
7441 tuple = build_tree_list (default_value, parm_decl);
7442 TREE_VEC_ELT (new_vec, i) = tuple;
7446 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
7447 - TMPL_ARGS_DEPTH (args)),
7448 new_vec, NULL_TREE);
7451 --processing_template_decl;
7456 /* Substitute the ARGS into the indicated aggregate (or enumeration)
7457 type T. If T is not an aggregate or enumeration type, it is
7458 handled as if by tsubst. IN_DECL is as for tsubst. If
7459 ENTERING_SCOPE is nonzero, T is the context for a template which
7460 we are presently tsubst'ing. Return the substituted value. */
7463 tsubst_aggr_type (tree t,
7465 tsubst_flags_t complain,
7472 switch (TREE_CODE (t))
7475 if (TYPE_PTRMEMFUNC_P (t))
7476 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
7478 /* Else fall through. */
7481 if (TYPE_TEMPLATE_INFO (t))
7486 bool saved_skip_evaluation;
7488 /* In "sizeof(X<I>)" we need to evaluate "I". */
7489 saved_skip_evaluation = skip_evaluation;
7490 skip_evaluation = false;
7492 /* First, determine the context for the type we are looking
7494 context = TYPE_CONTEXT (t);
7496 context = tsubst_aggr_type (context, args, complain,
7497 in_decl, /*entering_scope=*/1);
7499 /* Then, figure out what arguments are appropriate for the
7500 type we are trying to find. For example, given:
7502 template <class T> struct S;
7503 template <class T, class U> void f(T, U) { S<U> su; }
7505 and supposing that we are instantiating f<int, double>,
7506 then our ARGS will be {int, double}, but, when looking up
7507 S we only want {double}. */
7508 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
7510 if (argvec == error_mark_node)
7511 r = error_mark_node;
7514 r = lookup_template_class (t, argvec, in_decl, context,
7515 entering_scope, complain);
7516 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7519 skip_evaluation = saved_skip_evaluation;
7524 /* This is not a template type, so there's nothing to do. */
7528 return tsubst (t, args, complain, in_decl);
7532 /* Substitute into the default argument ARG (a default argument for
7533 FN), which has the indicated TYPE. */
7536 tsubst_default_argument (tree fn, tree type, tree arg)
7538 tree saved_class_ptr = NULL_TREE;
7539 tree saved_class_ref = NULL_TREE;
7541 /* This default argument came from a template. Instantiate the
7542 default argument here, not in tsubst. In the case of
7551 we must be careful to do name lookup in the scope of S<T>,
7552 rather than in the current class. */
7553 push_access_scope (fn);
7554 /* The "this" pointer is not valid in a default argument. */
7557 saved_class_ptr = current_class_ptr;
7558 cp_function_chain->x_current_class_ptr = NULL_TREE;
7559 saved_class_ref = current_class_ref;
7560 cp_function_chain->x_current_class_ref = NULL_TREE;
7563 push_deferring_access_checks(dk_no_deferred);
7564 /* The default argument expression may cause implicitly defined
7565 member functions to be synthesized, which will result in garbage
7566 collection. We must treat this situation as if we were within
7567 the body of function so as to avoid collecting live data on the
7570 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
7571 tf_warning_or_error, NULL_TREE,
7572 /*integral_constant_expression_p=*/false);
7574 pop_deferring_access_checks();
7576 /* Restore the "this" pointer. */
7579 cp_function_chain->x_current_class_ptr = saved_class_ptr;
7580 cp_function_chain->x_current_class_ref = saved_class_ref;
7583 pop_access_scope (fn);
7585 /* Make sure the default argument is reasonable. */
7586 arg = check_default_argument (type, arg);
7591 /* Substitute into all the default arguments for FN. */
7594 tsubst_default_arguments (tree fn)
7599 tmpl_args = DECL_TI_ARGS (fn);
7601 /* If this function is not yet instantiated, we certainly don't need
7602 its default arguments. */
7603 if (uses_template_parms (tmpl_args))
7606 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
7608 arg = TREE_CHAIN (arg))
7609 if (TREE_PURPOSE (arg))
7610 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
7612 TREE_PURPOSE (arg));
7615 /* Substitute the ARGS into the T, which is a _DECL. Return the
7616 result of the substitution. Issue error and warning messages under
7617 control of COMPLAIN. */
7620 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
7622 location_t saved_loc;
7626 /* Set the filename and linenumber to improve error-reporting. */
7627 saved_loc = input_location;
7628 input_location = DECL_SOURCE_LOCATION (t);
7630 switch (TREE_CODE (t))
7634 /* We can get here when processing a member function template,
7635 member class template, and template template parameter of
7636 a template class. */
7637 tree decl = DECL_TEMPLATE_RESULT (t);
7642 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7644 /* Template template parameter is treated here. */
7645 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7646 if (new_type == error_mark_node)
7647 return error_mark_node;
7650 TREE_CHAIN (r) = NULL_TREE;
7651 TREE_TYPE (r) = new_type;
7652 DECL_TEMPLATE_RESULT (r)
7653 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
7654 DECL_TEMPLATE_PARMS (r)
7655 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
7657 TYPE_NAME (new_type) = r;
7661 /* We might already have an instance of this template.
7662 The ARGS are for the surrounding class type, so the
7663 full args contain the tsubst'd args for the context,
7664 plus the innermost args from the template decl. */
7665 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
7666 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
7667 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
7668 /* Because this is a template, the arguments will still be
7669 dependent, even after substitution. If
7670 PROCESSING_TEMPLATE_DECL is not set, the dependency
7671 predicates will short-circuit. */
7672 ++processing_template_decl;
7673 full_args = tsubst_template_args (tmpl_args, args,
7675 --processing_template_decl;
7676 if (full_args == error_mark_node)
7677 return error_mark_node;
7679 /* tsubst_template_args doesn't copy the vector if
7680 nothing changed. But, *something* should have
7682 gcc_assert (full_args != tmpl_args);
7684 spec = retrieve_specialization (t, full_args,
7685 /*class_specializations_p=*/true);
7686 if (spec != NULL_TREE)
7692 /* Make a new template decl. It will be similar to the
7693 original, but will record the current template arguments.
7694 We also create a new function declaration, which is just
7695 like the old one, but points to this new template, rather
7696 than the old one. */
7698 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
7699 TREE_CHAIN (r) = NULL_TREE;
7701 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
7703 if (TREE_CODE (decl) == TYPE_DECL)
7706 ++processing_template_decl;
7707 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7708 --processing_template_decl;
7709 if (new_type == error_mark_node)
7710 return error_mark_node;
7712 TREE_TYPE (r) = new_type;
7713 CLASSTYPE_TI_TEMPLATE (new_type) = r;
7714 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
7715 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
7716 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
7721 ++processing_template_decl;
7722 new_decl = tsubst (decl, args, complain, in_decl);
7723 --processing_template_decl;
7724 if (new_decl == error_mark_node)
7725 return error_mark_node;
7727 DECL_TEMPLATE_RESULT (r) = new_decl;
7728 DECL_TI_TEMPLATE (new_decl) = r;
7729 TREE_TYPE (r) = TREE_TYPE (new_decl);
7730 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
7731 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
7734 SET_DECL_IMPLICIT_INSTANTIATION (r);
7735 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
7736 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
7738 /* The template parameters for this new template are all the
7739 template parameters for the old template, except the
7740 outermost level of parameters. */
7741 DECL_TEMPLATE_PARMS (r)
7742 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
7745 if (PRIMARY_TEMPLATE_P (t))
7746 DECL_PRIMARY_TEMPLATE (r) = r;
7748 if (TREE_CODE (decl) != TYPE_DECL)
7749 /* Record this non-type partial instantiation. */
7750 register_specialization (r, t,
7751 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
7759 tree argvec = NULL_TREE;
7767 /* Nobody should be tsubst'ing into non-template functions. */
7768 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
7770 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
7775 /* If T is not dependent, just return it. We have to
7776 increment PROCESSING_TEMPLATE_DECL because
7777 value_dependent_expression_p assumes that nothing is
7778 dependent when PROCESSING_TEMPLATE_DECL is zero. */
7779 ++processing_template_decl;
7780 dependent_p = value_dependent_expression_p (t);
7781 --processing_template_decl;
7785 /* Calculate the most general template of which R is a
7786 specialization, and the complete set of arguments used to
7788 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
7789 argvec = tsubst_template_args (DECL_TI_ARGS
7790 (DECL_TEMPLATE_RESULT (gen_tmpl)),
7791 args, complain, in_decl);
7793 /* Check to see if we already have this specialization. */
7794 spec = retrieve_specialization (gen_tmpl, argvec,
7795 /*class_specializations_p=*/false);
7803 /* We can see more levels of arguments than parameters if
7804 there was a specialization of a member template, like
7807 template <class T> struct S { template <class U> void f(); }
7808 template <> template <class U> void S<int>::f(U);
7810 Here, we'll be substituting into the specialization,
7811 because that's where we can find the code we actually
7812 want to generate, but we'll have enough arguments for
7813 the most general template.
7815 We also deal with the peculiar case:
7817 template <class T> struct S {
7818 template <class U> friend void f();
7820 template <class U> void f() {}
7822 template void f<double>();
7824 Here, the ARGS for the instantiation of will be {int,
7825 double}. But, we only need as many ARGS as there are
7826 levels of template parameters in CODE_PATTERN. We are
7827 careful not to get fooled into reducing the ARGS in
7830 template <class T> struct S { template <class U> void f(U); }
7831 template <class T> template <> void S<T>::f(int) {}
7833 which we can spot because the pattern will be a
7834 specialization in this case. */
7835 args_depth = TMPL_ARGS_DEPTH (args);
7837 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
7838 if (args_depth > parms_depth
7839 && !DECL_TEMPLATE_SPECIALIZATION (t))
7840 args = get_innermost_template_args (args, parms_depth);
7844 /* This special case arises when we have something like this:
7846 template <class T> struct S {
7847 friend void f<int>(int, double);
7850 Here, the DECL_TI_TEMPLATE for the friend declaration
7851 will be an IDENTIFIER_NODE. We are being called from
7852 tsubst_friend_function, and we want only to create a
7853 new decl (R) with appropriate types so that we can call
7854 determine_specialization. */
7855 gen_tmpl = NULL_TREE;
7858 if (DECL_CLASS_SCOPE_P (t))
7860 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
7864 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
7865 complain, t, /*entering_scope=*/1);
7870 ctx = DECL_CONTEXT (t);
7872 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
7873 if (type == error_mark_node)
7874 return error_mark_node;
7876 /* We do NOT check for matching decls pushed separately at this
7877 point, as they may not represent instantiations of this
7878 template, and in any case are considered separate under the
7881 DECL_USE_TEMPLATE (r) = 0;
7882 TREE_TYPE (r) = type;
7883 /* Clear out the mangled name and RTL for the instantiation. */
7884 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
7885 SET_DECL_RTL (r, NULL_RTX);
7886 DECL_INITIAL (r) = NULL_TREE;
7887 DECL_CONTEXT (r) = ctx;
7889 if (member && DECL_CONV_FN_P (r))
7890 /* Type-conversion operator. Reconstruct the name, in
7891 case it's the name of one of the template's parameters. */
7892 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
7894 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
7896 DECL_RESULT (r) = NULL_TREE;
7898 TREE_STATIC (r) = 0;
7899 TREE_PUBLIC (r) = TREE_PUBLIC (t);
7900 DECL_EXTERNAL (r) = 1;
7901 /* If this is an instantiation of a function with internal
7902 linkage, we already know what object file linkage will be
7903 assigned to the instantiation. */
7904 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
7905 DECL_DEFER_OUTPUT (r) = 0;
7906 TREE_CHAIN (r) = NULL_TREE;
7907 DECL_PENDING_INLINE_INFO (r) = 0;
7908 DECL_PENDING_INLINE_P (r) = 0;
7909 DECL_SAVED_TREE (r) = NULL_TREE;
7911 if (DECL_CLONED_FUNCTION (r))
7913 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
7915 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
7916 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
7919 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
7920 this in the special friend case mentioned above where
7921 GEN_TMPL is NULL. */
7924 DECL_TEMPLATE_INFO (r)
7925 = tree_cons (gen_tmpl, argvec, NULL_TREE);
7926 SET_DECL_IMPLICIT_INSTANTIATION (r);
7927 register_specialization (r, gen_tmpl, argvec, false);
7929 /* We're not supposed to instantiate default arguments
7930 until they are called, for a template. But, for a
7933 template <class T> void f ()
7934 { extern void g(int i = T()); }
7936 we should do the substitution when the template is
7937 instantiated. We handle the member function case in
7938 instantiate_class_template since the default arguments
7939 might refer to other members of the class. */
7941 && !PRIMARY_TEMPLATE_P (gen_tmpl)
7942 && !uses_template_parms (argvec))
7943 tsubst_default_arguments (r);
7946 DECL_TEMPLATE_INFO (r) = NULL_TREE;
7948 /* Copy the list of befriending classes. */
7949 for (friends = &DECL_BEFRIENDING_CLASSES (r);
7951 friends = &TREE_CHAIN (*friends))
7953 *friends = copy_node (*friends);
7954 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
7959 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
7961 maybe_retrofit_in_chrg (r);
7962 if (DECL_CONSTRUCTOR_P (r))
7963 grok_ctor_properties (ctx, r);
7964 /* If this is an instantiation of a member template, clone it.
7965 If it isn't, that'll be handled by
7966 clone_constructors_and_destructors. */
7967 if (PRIMARY_TEMPLATE_P (gen_tmpl))
7968 clone_function_decl (r, /*update_method_vec_p=*/0);
7970 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r))
7971 && !grok_op_properties (r, (complain & tf_error) != 0))
7972 return error_mark_node;
7974 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
7975 SET_DECL_FRIEND_CONTEXT (r,
7976 tsubst (DECL_FRIEND_CONTEXT (t),
7977 args, complain, in_decl));
7979 /* Possibly limit visibility based on template args. */
7980 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
7981 if (DECL_VISIBILITY_SPECIFIED (t))
7983 DECL_VISIBILITY_SPECIFIED (r) = 0;
7985 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
7987 determine_visibility (r);
7989 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
7990 args, complain, in_decl);
7996 tree type = NULL_TREE;
7998 tree expanded_types = NULL_TREE;
7999 tree prev_r = NULL_TREE;
8000 tree first_r = NULL_TREE;
8002 if (FUNCTION_PARAMETER_PACK_P (t))
8004 /* If there is a local specialization that isn't a
8005 parameter pack, it means that we're doing a "simple"
8006 substitution from inside tsubst_pack_expansion. Just
8007 return the local specialization (which will be a single
8009 tree spec = NULL_TREE;
8010 if (local_specializations)
8011 spec = retrieve_local_specialization (t);
8013 && TREE_CODE (spec) == PARM_DECL
8014 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
8017 /* Expand the TYPE_PACK_EXPANSION that provides the types for
8018 the parameters in this function parameter pack. */
8019 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
8021 if (TREE_CODE (expanded_types) == TREE_VEC)
8023 len = TREE_VEC_LENGTH (expanded_types);
8025 /* Zero-length parameter packs are boring. Just substitute
8028 return tsubst (TREE_CHAIN (t), args, complain,
8033 /* All we did was update the type. Make a note of that. */
8034 type = expanded_types;
8035 expanded_types = NULL_TREE;
8039 /* Loop through all of the parameter's we'll build. When T is
8040 a function parameter pack, LEN is the number of expanded
8041 types in EXPANDED_TYPES; otherwise, LEN is 1. */
8043 for (i = 0; i < len; ++i)
8047 if (DECL_TEMPLATE_PARM_P (t))
8048 SET_DECL_TEMPLATE_PARM_P (r);
8051 /* We're on the Ith parameter of the function parameter
8054 /* Get the Ith type. */
8055 type = TREE_VEC_ELT (expanded_types, i);
8058 /* Rename the parameter to include the index. */
8060 make_ith_pack_parameter_name (DECL_NAME (r), i);
8063 /* We're dealing with a normal parameter. */
8064 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8066 type = type_decays_to (type);
8067 TREE_TYPE (r) = type;
8068 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8070 if (DECL_INITIAL (r))
8072 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
8073 DECL_INITIAL (r) = TREE_TYPE (r);
8075 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
8079 DECL_CONTEXT (r) = NULL_TREE;
8081 if (!DECL_TEMPLATE_PARM_P (r))
8082 DECL_ARG_TYPE (r) = type_passed_as (type);
8084 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8085 args, complain, in_decl);
8087 /* Keep track of the first new parameter we
8088 generate. That's what will be returned to the
8093 /* Build a proper chain of parameters when substituting
8094 into a function parameter pack. */
8096 TREE_CHAIN (prev_r) = r;
8100 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
8101 complain, TREE_CHAIN (t));
8103 /* FIRST_R contains the start of the chain we've built. */
8113 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8114 if (type == error_mark_node)
8115 return error_mark_node;
8116 TREE_TYPE (r) = type;
8117 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8119 /* DECL_INITIAL gives the number of bits in a bit-field. */
8121 = tsubst_expr (DECL_INITIAL (t), args,
8123 /*integral_constant_expression_p=*/true);
8124 /* We don't have to set DECL_CONTEXT here; it is set by
8125 finish_member_declaration. */
8126 TREE_CHAIN (r) = NULL_TREE;
8127 if (VOID_TYPE_P (type))
8128 error ("instantiation of %q+D as type %qT", r, type);
8130 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8131 args, complain, in_decl);
8136 /* We reach here only for member using decls. */
8137 if (DECL_DEPENDENT_P (t))
8139 r = do_class_using_decl
8140 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
8141 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
8143 r = error_mark_node;
8148 TREE_CHAIN (r) = NULL_TREE;
8155 tree argvec = NULL_TREE;
8156 tree gen_tmpl = NULL_TREE;
8158 tree tmpl = NULL_TREE;
8160 tree type = NULL_TREE;
8163 if (TREE_CODE (t) == TYPE_DECL
8164 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
8166 /* If this is the canonical decl, we don't have to
8167 mess with instantiations, and often we can't (for
8168 typename, template type parms and such). Note that
8169 TYPE_NAME is not correct for the above test if
8170 we've copied the type for a typedef. */
8171 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8172 if (type == error_mark_node)
8173 return error_mark_node;
8174 r = TYPE_NAME (type);
8178 /* Check to see if we already have the specialization we
8181 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
8183 /* T is a static data member or namespace-scope entity.
8184 We have to substitute into namespace-scope variables
8185 (even though such entities are never templates) because
8188 template <class T> void f() { extern T t; }
8190 where the entity referenced is not known until
8191 instantiation time. */
8193 ctx = DECL_CONTEXT (t);
8194 if (DECL_CLASS_SCOPE_P (t))
8196 ctx = tsubst_aggr_type (ctx, args,
8198 in_decl, /*entering_scope=*/1);
8199 /* If CTX is unchanged, then T is in fact the
8200 specialization we want. That situation occurs when
8201 referencing a static data member within in its own
8202 class. We can use pointer equality, rather than
8203 same_type_p, because DECL_CONTEXT is always
8205 if (ctx == DECL_CONTEXT (t))
8211 tmpl = DECL_TI_TEMPLATE (t);
8212 gen_tmpl = most_general_template (tmpl);
8213 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
8214 spec = (retrieve_specialization
8216 /*class_specializations_p=*/false));
8221 /* A local variable. */
8223 /* Subsequent calls to pushdecl will fill this in. */
8225 spec = retrieve_local_specialization (t);
8227 /* If we already have the specialization we need, there is
8228 nothing more to do. */
8235 /* Create a new node for the specialization we need. */
8237 if (type == NULL_TREE)
8238 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8239 if (TREE_CODE (r) == VAR_DECL)
8241 /* Even if the original location is out of scope, the
8242 newly substituted one is not. */
8243 DECL_DEAD_FOR_LOCAL (r) = 0;
8244 DECL_INITIALIZED_P (r) = 0;
8245 DECL_TEMPLATE_INSTANTIATED (r) = 0;
8246 if (type == error_mark_node)
8247 return error_mark_node;
8248 if (TREE_CODE (type) == FUNCTION_TYPE)
8250 /* It may seem that this case cannot occur, since:
8255 declares a function, not a variable. However:
8258 template <typename T> void g() { T t; }
8259 template void g<f>();
8261 is an attempt to declare a variable with function
8263 error ("variable %qD has function type",
8264 /* R is not yet sufficiently initialized, so we
8265 just use its name. */
8267 return error_mark_node;
8269 type = complete_type (type);
8270 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
8271 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
8272 type = check_var_type (DECL_NAME (r), type);
8274 if (DECL_HAS_VALUE_EXPR_P (t))
8276 tree ve = DECL_VALUE_EXPR (t);
8277 ve = tsubst_expr (ve, args, complain, in_decl,
8278 /*constant_expression_p=*/false);
8279 SET_DECL_VALUE_EXPR (r, ve);
8282 else if (DECL_SELF_REFERENCE_P (t))
8283 SET_DECL_SELF_REFERENCE_P (r);
8284 TREE_TYPE (r) = type;
8285 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8286 DECL_CONTEXT (r) = ctx;
8287 /* Clear out the mangled name and RTL for the instantiation. */
8288 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8289 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8290 SET_DECL_RTL (r, NULL_RTX);
8291 /* The initializer must not be expanded until it is required;
8293 DECL_INITIAL (r) = NULL_TREE;
8294 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8295 SET_DECL_RTL (r, NULL_RTX);
8296 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
8297 if (TREE_CODE (r) == VAR_DECL)
8299 /* Possibly limit visibility based on template args. */
8300 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8301 if (DECL_VISIBILITY_SPECIFIED (t))
8303 DECL_VISIBILITY_SPECIFIED (r) = 0;
8305 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8307 determine_visibility (r);
8309 /* Preserve a typedef that names a type. */
8310 else if (TREE_CODE (r) == TYPE_DECL
8311 && DECL_ORIGINAL_TYPE (t)
8312 && type != error_mark_node)
8314 DECL_ORIGINAL_TYPE (r) = tsubst (DECL_ORIGINAL_TYPE (t),
8315 args, complain, in_decl);
8316 TREE_TYPE (r) = type = build_variant_type_copy (type);
8317 TYPE_NAME (type) = r;
8322 /* A static data member declaration is always marked
8323 external when it is declared in-class, even if an
8324 initializer is present. We mimic the non-template
8326 DECL_EXTERNAL (r) = 1;
8328 register_specialization (r, gen_tmpl, argvec, false);
8329 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
8330 SET_DECL_IMPLICIT_INSTANTIATION (r);
8333 register_local_specialization (r, t);
8335 TREE_CHAIN (r) = NULL_TREE;
8337 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
8338 (int) ATTR_FLAG_TYPE_IN_PLACE,
8339 args, complain, in_decl);
8348 /* Restore the file and line information. */
8349 input_location = saved_loc;
8354 /* Substitute into the ARG_TYPES of a function type. */
8357 tsubst_arg_types (tree arg_types,
8359 tsubst_flags_t complain,
8362 tree remaining_arg_types;
8363 tree type = NULL_TREE;
8365 tree expanded_args = NULL_TREE;
8368 if (!arg_types || arg_types == void_list_node)
8371 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
8372 args, complain, in_decl);
8373 if (remaining_arg_types == error_mark_node)
8374 return error_mark_node;
8376 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
8378 /* For a pack expansion, perform substitution on the
8379 entire expression. Later on, we'll handle the arguments
8381 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
8382 args, complain, in_decl);
8384 if (TREE_CODE (expanded_args) == TREE_VEC)
8385 /* So that we'll spin through the parameters, one by one. */
8386 i = TREE_VEC_LENGTH (expanded_args);
8389 /* We only partially substituted into the parameter
8390 pack. Our type is TYPE_PACK_EXPANSION. */
8391 type = expanded_args;
8392 expanded_args = NULL_TREE;
8400 type = TREE_VEC_ELT (expanded_args, i);
8402 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
8404 if (type == error_mark_node)
8405 return error_mark_node;
8406 if (VOID_TYPE_P (type))
8408 if (complain & tf_error)
8410 error ("invalid parameter type %qT", type);
8412 error ("in declaration %q+D", in_decl);
8414 return error_mark_node;
8417 /* Do array-to-pointer, function-to-pointer conversion, and ignore
8418 top-level qualifiers as required. */
8419 type = TYPE_MAIN_VARIANT (type_decays_to (type));
8421 /* We do not substitute into default arguments here. The standard
8422 mandates that they be instantiated only when needed, which is
8423 done in build_over_call. */
8424 default_arg = TREE_PURPOSE (arg_types);
8426 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
8428 /* We've instantiated a template before its default arguments
8429 have been parsed. This can happen for a nested template
8430 class, and is not an error unless we require the default
8431 argument in a call of this function. */
8432 remaining_arg_types =
8433 tree_cons (default_arg, type, remaining_arg_types);
8434 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
8435 remaining_arg_types);
8438 remaining_arg_types =
8439 hash_tree_cons (default_arg, type, remaining_arg_types);
8442 return remaining_arg_types;
8445 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
8446 *not* handle the exception-specification for FNTYPE, because the
8447 initial substitution of explicitly provided template parameters
8448 during argument deduction forbids substitution into the
8449 exception-specification:
8453 All references in the function type of the function template to the
8454 corresponding template parameters are replaced by the specified tem-
8455 plate argument values. If a substitution in a template parameter or
8456 in the function type of the function template results in an invalid
8457 type, type deduction fails. [Note: The equivalent substitution in
8458 exception specifications is done only when the function is instanti-
8459 ated, at which point a program is ill-formed if the substitution
8460 results in an invalid type.] */
8463 tsubst_function_type (tree t,
8465 tsubst_flags_t complain,
8472 /* The TYPE_CONTEXT is not used for function/method types. */
8473 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
8475 /* Substitute the return type. */
8476 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8477 if (return_type == error_mark_node)
8478 return error_mark_node;
8479 /* The standard does not presently indicate that creation of a
8480 function type with an invalid return type is a deduction failure.
8481 However, that is clearly analogous to creating an array of "void"
8482 or a reference to a reference. This is core issue #486. */
8483 if (TREE_CODE (return_type) == ARRAY_TYPE
8484 || TREE_CODE (return_type) == FUNCTION_TYPE)
8486 if (complain & tf_error)
8488 if (TREE_CODE (return_type) == ARRAY_TYPE)
8489 error ("function returning an array");
8491 error ("function returning a function");
8493 return error_mark_node;
8496 /* Substitute the argument types. */
8497 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
8499 if (arg_types == error_mark_node)
8500 return error_mark_node;
8502 if (TYPE_QUALS (return_type) != TYPE_UNQUALIFIED
8503 && in_decl != NULL_TREE
8504 && !TREE_NO_WARNING (in_decl)
8505 && (SCALAR_TYPE_P (return_type) || VOID_TYPE_P (return_type)))
8506 warning (OPT_Wreturn_type,
8507 "type qualifiers ignored on function return type");
8509 /* Construct a new type node and return it. */
8510 if (TREE_CODE (t) == FUNCTION_TYPE)
8511 fntype = build_function_type (return_type, arg_types);
8514 tree r = TREE_TYPE (TREE_VALUE (arg_types));
8515 if (! IS_AGGR_TYPE (r))
8519 Type deduction may fail for any of the following
8522 -- Attempting to create "pointer to member of T" when T
8523 is not a class type. */
8524 if (complain & tf_error)
8525 error ("creating pointer to member function of non-class type %qT",
8527 return error_mark_node;
8530 fntype = build_method_type_directly (r, return_type,
8531 TREE_CHAIN (arg_types));
8533 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
8534 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
8539 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
8540 ARGS into that specification, and return the substituted
8541 specification. If there is no specification, return NULL_TREE. */
8544 tsubst_exception_specification (tree fntype,
8546 tsubst_flags_t complain,
8552 specs = TYPE_RAISES_EXCEPTIONS (fntype);
8553 new_specs = NULL_TREE;
8556 if (! TREE_VALUE (specs))
8563 tree expanded_specs = NULL_TREE;
8565 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
8567 /* Expand the pack expansion type. */
8568 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
8571 len = TREE_VEC_LENGTH (expanded_specs);
8574 for (i = 0; i < len; ++i)
8577 spec = TREE_VEC_ELT (expanded_specs, i);
8579 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
8580 if (spec == error_mark_node)
8582 new_specs = add_exception_specifier (new_specs, spec,
8586 specs = TREE_CHAIN (specs);
8592 /* Take the tree structure T and replace template parameters used
8593 therein with the argument vector ARGS. IN_DECL is an associated
8594 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
8595 Issue error and warning messages under control of COMPLAIN. Note
8596 that we must be relatively non-tolerant of extensions here, in
8597 order to preserve conformance; if we allow substitutions that
8598 should not be allowed, we may allow argument deductions that should
8599 not succeed, and therefore report ambiguous overload situations
8600 where there are none. In theory, we could allow the substitution,
8601 but indicate that it should have failed, and allow our caller to
8602 make sure that the right thing happens, but we don't try to do this
8605 This function is used for dealing with types, decls and the like;
8606 for expressions, use tsubst_expr or tsubst_copy. */
8609 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8613 if (t == NULL_TREE || t == error_mark_node
8614 || t == integer_type_node
8615 || t == void_type_node
8616 || t == char_type_node
8617 || t == unknown_type_node
8618 || TREE_CODE (t) == NAMESPACE_DECL)
8622 return tsubst_decl (t, args, complain);
8624 if (TREE_CODE (t) == IDENTIFIER_NODE)
8625 type = IDENTIFIER_TYPE_VALUE (t);
8627 type = TREE_TYPE (t);
8629 gcc_assert (type != unknown_type_node);
8631 /* Reuse typedefs. We need to do this to handle dependent attributes,
8632 such as attribute aligned. */
8635 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
8637 tree decl = TYPE_NAME (t);
8639 if (DECL_CLASS_SCOPE_P (decl)
8640 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl)))
8642 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
8643 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
8644 r = retrieve_specialization (tmpl, gen_args, false);
8646 else if (DECL_FUNCTION_SCOPE_P (decl))
8647 r = retrieve_local_specialization (decl);
8654 r = cp_build_qualified_type_real
8655 (r, cp_type_quals (t) | cp_type_quals (r),
8656 complain | tf_ignore_bad_quals);
8659 /* Else we must be instantiating the typedef, so fall through. */
8663 && TREE_CODE (t) != TYPENAME_TYPE
8664 && TREE_CODE (t) != IDENTIFIER_NODE
8665 && TREE_CODE (t) != FUNCTION_TYPE
8666 && TREE_CODE (t) != METHOD_TYPE)
8667 type = tsubst (type, args, complain, in_decl);
8668 if (type == error_mark_node)
8669 return error_mark_node;
8671 switch (TREE_CODE (t))
8676 return tsubst_aggr_type (t, args, complain, in_decl,
8677 /*entering_scope=*/0);
8680 case IDENTIFIER_NODE:
8692 if (t == integer_type_node)
8695 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
8696 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
8700 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
8702 max = tsubst_expr (omax, args, complain, in_decl,
8703 /*integral_constant_expression_p=*/false);
8704 max = fold_decl_constant_value (max);
8706 if (TREE_CODE (max) != INTEGER_CST
8707 && TREE_CODE (max) != TEMPLATE_PARM_INDEX
8708 && !at_function_scope_p ())
8710 if (complain & tf_error)
8711 error ("array bound is not an integer constant");
8712 return error_mark_node;
8717 Type deduction may fail for any of the following
8720 Attempting to create an array with a size that is
8721 zero or negative. */
8722 if (integer_zerop (max) && !(complain & tf_error))
8723 /* We must fail if performing argument deduction (as
8724 indicated by the state of complain), so that
8725 another substitution can be found. */
8726 return error_mark_node;
8727 else if (TREE_CODE (max) == INTEGER_CST
8728 && INT_CST_LT (max, integer_zero_node))
8730 if (complain & tf_error)
8731 error ("creating array with negative size (%qE)", max);
8733 return error_mark_node;
8736 return compute_array_index_type (NULL_TREE, max);
8739 case TEMPLATE_TYPE_PARM:
8740 case TEMPLATE_TEMPLATE_PARM:
8741 case BOUND_TEMPLATE_TEMPLATE_PARM:
8742 case TEMPLATE_PARM_INDEX:
8747 tree arg = NULL_TREE;
8751 gcc_assert (TREE_VEC_LENGTH (args) > 0);
8752 template_parm_level_and_index (t, &level, &idx);
8754 levels = TMPL_ARGS_DEPTH (args);
8755 if (level <= levels)
8757 arg = TMPL_ARG (args, level, idx);
8759 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
8760 /* See through ARGUMENT_PACK_SELECT arguments. */
8761 arg = ARGUMENT_PACK_SELECT_ARG (arg);
8764 if (arg == error_mark_node)
8765 return error_mark_node;
8766 else if (arg != NULL_TREE)
8768 if (ARGUMENT_PACK_P (arg))
8769 /* If ARG is an argument pack, we don't actually want to
8770 perform a substitution here, because substitutions
8771 for argument packs are only done
8772 element-by-element. We can get to this point when
8773 substituting the type of a non-type template
8774 parameter pack, when that type actually contains
8775 template parameter packs from an outer template, e.g.,
8777 template<typename... Types> struct A {
8778 template<Types... Values> struct B { };
8782 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
8785 gcc_assert (TYPE_P (arg));
8787 /* cv-quals from the template are discarded when
8788 substituting in a function or reference type. */
8789 if (TREE_CODE (arg) == FUNCTION_TYPE
8790 || TREE_CODE (arg) == METHOD_TYPE
8791 || TREE_CODE (arg) == REFERENCE_TYPE)
8792 quals = cp_type_quals (arg);
8794 quals = cp_type_quals (arg) | cp_type_quals (t);
8796 return cp_build_qualified_type_real
8797 (arg, quals, complain | tf_ignore_bad_quals);
8799 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
8801 /* We are processing a type constructed from a
8802 template template parameter. */
8803 tree argvec = tsubst (TYPE_TI_ARGS (t),
8804 args, complain, in_decl);
8805 if (argvec == error_mark_node)
8806 return error_mark_node;
8808 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
8809 are resolving nested-types in the signature of a
8810 member function templates. Otherwise ARG is a
8811 TEMPLATE_DECL and is the real template to be
8813 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
8814 arg = TYPE_NAME (arg);
8816 r = lookup_template_class (arg,
8819 /*entering_scope=*/0,
8821 return cp_build_qualified_type_real
8822 (r, TYPE_QUALS (t), complain);
8825 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
8830 /* This can happen during the attempted tsubst'ing in
8831 unify. This means that we don't yet have any information
8832 about the template parameter in question. */
8835 /* If we get here, we must have been looking at a parm for a
8836 more deeply nested template. Make a new version of this
8837 template parameter, but with a lower level. */
8838 switch (TREE_CODE (t))
8840 case TEMPLATE_TYPE_PARM:
8841 case TEMPLATE_TEMPLATE_PARM:
8842 case BOUND_TEMPLATE_TEMPLATE_PARM:
8843 if (cp_type_quals (t))
8845 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
8846 r = cp_build_qualified_type_real
8847 (r, cp_type_quals (t),
8848 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
8849 ? tf_ignore_bad_quals : 0));
8854 TEMPLATE_TYPE_PARM_INDEX (r)
8855 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
8856 r, levels, args, complain);
8857 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
8858 TYPE_MAIN_VARIANT (r) = r;
8859 TYPE_POINTER_TO (r) = NULL_TREE;
8860 TYPE_REFERENCE_TO (r) = NULL_TREE;
8862 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
8863 /* We have reduced the level of the template
8864 template parameter, but not the levels of its
8865 template parameters, so canonical_type_parameter
8866 will not be able to find the canonical template
8867 template parameter for this level. Thus, we
8868 require structural equality checking to compare
8869 TEMPLATE_TEMPLATE_PARMs. */
8870 SET_TYPE_STRUCTURAL_EQUALITY (r);
8871 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
8872 SET_TYPE_STRUCTURAL_EQUALITY (r);
8874 TYPE_CANONICAL (r) = canonical_type_parameter (r);
8876 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
8878 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
8880 if (argvec == error_mark_node)
8881 return error_mark_node;
8883 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
8884 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
8889 case TEMPLATE_PARM_INDEX:
8890 r = reduce_template_parm_level (t, type, levels, args, complain);
8902 tree purpose, value, chain;
8904 if (t == void_list_node)
8907 purpose = TREE_PURPOSE (t);
8910 purpose = tsubst (purpose, args, complain, in_decl);
8911 if (purpose == error_mark_node)
8912 return error_mark_node;
8914 value = TREE_VALUE (t);
8917 value = tsubst (value, args, complain, in_decl);
8918 if (value == error_mark_node)
8919 return error_mark_node;
8921 chain = TREE_CHAIN (t);
8922 if (chain && chain != void_type_node)
8924 chain = tsubst (chain, args, complain, in_decl);
8925 if (chain == error_mark_node)
8926 return error_mark_node;
8928 if (purpose == TREE_PURPOSE (t)
8929 && value == TREE_VALUE (t)
8930 && chain == TREE_CHAIN (t))
8932 return hash_tree_cons (purpose, value, chain);
8936 /* We should never be tsubsting a binfo. */
8940 /* A vector of template arguments. */
8942 return tsubst_template_args (t, args, complain, in_decl);
8945 case REFERENCE_TYPE:
8947 enum tree_code code;
8949 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
8952 code = TREE_CODE (t);
8957 Type deduction may fail for any of the following
8960 -- Attempting to create a pointer to reference type.
8961 -- Attempting to create a reference to a reference type or
8962 a reference to void.
8964 Core issue 106 says that creating a reference to a reference
8965 during instantiation is no longer a cause for failure. We
8966 only enforce this check in strict C++98 mode. */
8967 if ((TREE_CODE (type) == REFERENCE_TYPE
8968 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
8969 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
8971 static location_t last_loc;
8973 /* We keep track of the last time we issued this error
8974 message to avoid spewing a ton of messages during a
8975 single bad template instantiation. */
8976 if (complain & tf_error
8977 #ifdef USE_MAPPED_LOCATION
8978 && last_loc != input_location
8980 && (last_loc.line != input_line
8981 || last_loc.file != input_filename)
8985 if (TREE_CODE (type) == VOID_TYPE)
8986 error ("forming reference to void");
8988 error ("forming %s to reference type %qT",
8989 (code == POINTER_TYPE) ? "pointer" : "reference",
8991 last_loc = input_location;
8994 return error_mark_node;
8996 else if (code == POINTER_TYPE)
8998 r = build_pointer_type (type);
8999 if (TREE_CODE (type) == METHOD_TYPE)
9000 r = build_ptrmemfunc_type (r);
9002 else if (TREE_CODE (type) == REFERENCE_TYPE)
9003 /* In C++0x, during template argument substitution, when there is an
9004 attempt to create a reference to a reference type, reference
9005 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
9007 "If a template-argument for a template-parameter T names a type
9008 that is a reference to a type A, an attempt to create the type
9009 'lvalue reference to cv T' creates the type 'lvalue reference to
9010 A,' while an attempt to create the type type rvalue reference to
9011 cv T' creates the type T"
9013 r = cp_build_reference_type
9015 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
9017 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
9018 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
9020 if (r != error_mark_node)
9021 /* Will this ever be needed for TYPE_..._TO values? */
9028 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
9029 if (r == error_mark_node || !IS_AGGR_TYPE (r))
9033 Type deduction may fail for any of the following
9036 -- Attempting to create "pointer to member of T" when T
9037 is not a class type. */
9038 if (complain & tf_error)
9039 error ("creating pointer to member of non-class type %qT", r);
9040 return error_mark_node;
9042 if (TREE_CODE (type) == REFERENCE_TYPE)
9044 if (complain & tf_error)
9045 error ("creating pointer to member reference type %qT", type);
9046 return error_mark_node;
9048 if (TREE_CODE (type) == VOID_TYPE)
9050 if (complain & tf_error)
9051 error ("creating pointer to member of type void");
9052 return error_mark_node;
9054 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
9055 if (TREE_CODE (type) == FUNCTION_TYPE)
9057 /* The type of the implicit object parameter gets its
9058 cv-qualifiers from the FUNCTION_TYPE. */
9060 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
9061 cp_type_quals (type));
9063 method_type = build_method_type_directly (this_type,
9065 TYPE_ARG_TYPES (type));
9066 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
9067 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
9071 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
9080 fntype = tsubst_function_type (t, args, complain, in_decl);
9081 if (fntype == error_mark_node)
9082 return error_mark_node;
9084 /* Substitute the exception specification. */
9085 specs = tsubst_exception_specification (t, args, complain,
9087 if (specs == error_mark_node)
9088 return error_mark_node;
9090 fntype = build_exception_variant (fntype, specs);
9095 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
9096 if (domain == error_mark_node)
9097 return error_mark_node;
9099 /* As an optimization, we avoid regenerating the array type if
9100 it will obviously be the same as T. */
9101 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
9104 /* These checks should match the ones in grokdeclarator.
9108 The deduction may fail for any of the following reasons:
9110 -- Attempting to create an array with an element type that
9111 is void, a function type, or a reference type, or [DR337]
9112 an abstract class type. */
9113 if (TREE_CODE (type) == VOID_TYPE
9114 || TREE_CODE (type) == FUNCTION_TYPE
9115 || TREE_CODE (type) == REFERENCE_TYPE)
9117 if (complain & tf_error)
9118 error ("creating array of %qT", type);
9119 return error_mark_node;
9121 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
9123 if (complain & tf_error)
9124 error ("creating array of %qT, which is an abstract class type",
9126 return error_mark_node;
9129 r = build_cplus_array_type (type, domain);
9131 if (TYPE_USER_ALIGN (t))
9133 TYPE_ALIGN (r) = TYPE_ALIGN (t);
9134 TYPE_USER_ALIGN (r) = 1;
9143 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9144 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9146 if (e1 == error_mark_node || e2 == error_mark_node)
9147 return error_mark_node;
9149 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
9155 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9156 if (e == error_mark_node)
9157 return error_mark_node;
9159 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
9164 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9165 in_decl, /*entering_scope=*/1);
9166 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
9169 if (ctx == error_mark_node || f == error_mark_node)
9170 return error_mark_node;
9172 if (!IS_AGGR_TYPE (ctx))
9174 if (complain & tf_error)
9175 error ("%qT is not a class, struct, or union type", ctx);
9176 return error_mark_node;
9178 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
9180 /* Normally, make_typename_type does not require that the CTX
9181 have complete type in order to allow things like:
9183 template <class T> struct S { typename S<T>::X Y; };
9185 But, such constructs have already been resolved by this
9186 point, so here CTX really should have complete type, unless
9187 it's a partial instantiation. */
9188 ctx = complete_type (ctx);
9189 if (!COMPLETE_TYPE_P (ctx))
9191 if (complain & tf_error)
9192 cxx_incomplete_type_error (NULL_TREE, ctx);
9193 return error_mark_node;
9197 f = make_typename_type (ctx, f, typename_type,
9198 (complain & tf_error) | tf_keep_type_decl);
9199 if (f == error_mark_node)
9201 if (TREE_CODE (f) == TYPE_DECL)
9203 complain |= tf_ignore_bad_quals;
9207 if (TREE_CODE (f) != TYPENAME_TYPE)
9209 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
9210 error ("%qT resolves to %qT, which is not an enumeration type",
9212 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
9213 error ("%qT resolves to %qT, which is is not a class type",
9217 return cp_build_qualified_type_real
9218 (f, cp_type_quals (f) | cp_type_quals (t), complain);
9221 case UNBOUND_CLASS_TEMPLATE:
9223 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9224 in_decl, /*entering_scope=*/1);
9225 tree name = TYPE_IDENTIFIER (t);
9226 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
9228 if (ctx == error_mark_node || name == error_mark_node)
9229 return error_mark_node;
9232 parm_list = tsubst_template_parms (parm_list, args, complain);
9233 return make_unbound_class_template (ctx, name, parm_list, complain);
9243 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9244 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
9245 /*integral_constant_expression_p=*/false);
9246 if (e1 == error_mark_node || e2 == error_mark_node)
9247 return error_mark_node;
9249 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
9254 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9255 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9256 if (e1 == error_mark_node || e2 == error_mark_node)
9257 return error_mark_node;
9259 return build_qualified_name (/*type=*/NULL_TREE,
9260 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
9267 type = finish_typeof (tsubst_expr
9268 (TYPEOF_TYPE_EXPR (t), args,
9270 /*integral_constant_expression_p=*/false));
9271 return cp_build_qualified_type_real (type,
9273 | cp_type_quals (type),
9282 finish_decltype_type (tsubst_expr
9283 (DECLTYPE_TYPE_EXPR (t), args,
9285 /*integral_constant_expression_p=*/false),
9286 DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
9287 return cp_build_qualified_type_real (type,
9289 | cp_type_quals (type),
9293 case TYPE_ARGUMENT_PACK:
9294 case NONTYPE_ARGUMENT_PACK:
9296 tree r = make_node (TREE_CODE (t));
9298 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
9302 SET_ARGUMENT_PACK_ARGS (r, packed_out);
9304 /* For template nontype argument packs, also substitute into
9306 if (TREE_CODE (t) == NONTYPE_ARGUMENT_PACK)
9307 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
9314 sorry ("use of %qs in template",
9315 tree_code_name [(int) TREE_CODE (t)]);
9316 return error_mark_node;
9320 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
9321 type of the expression on the left-hand side of the "." or "->"
9325 tsubst_baselink (tree baselink, tree object_type,
9326 tree args, tsubst_flags_t complain, tree in_decl)
9329 tree qualifying_scope;
9332 tree template_args = 0;
9333 bool template_id_p = false;
9335 /* A baselink indicates a function from a base class. Both the
9336 BASELINK_ACCESS_BINFO and the base class referenced may
9337 indicate bases of the template class, rather than the
9338 instantiated class. In addition, lookups that were not
9339 ambiguous before may be ambiguous now. Therefore, we perform
9340 the lookup again. */
9341 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
9342 qualifying_scope = tsubst (qualifying_scope, args,
9344 fns = BASELINK_FUNCTIONS (baselink);
9345 optype = BASELINK_OPTYPE (baselink);
9346 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
9348 template_id_p = true;
9349 template_args = TREE_OPERAND (fns, 1);
9350 fns = TREE_OPERAND (fns, 0);
9352 template_args = tsubst_template_args (template_args, args,
9355 name = DECL_NAME (get_first_fn (fns));
9356 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
9358 /* If lookup found a single function, mark it as used at this
9359 point. (If it lookup found multiple functions the one selected
9360 later by overload resolution will be marked as used at that
9362 if (BASELINK_P (baselink))
9363 fns = BASELINK_FUNCTIONS (baselink);
9364 if (!template_id_p && !really_overloaded_fn (fns))
9365 mark_used (OVL_CURRENT (fns));
9367 /* Add back the template arguments, if present. */
9368 if (BASELINK_P (baselink) && template_id_p)
9369 BASELINK_FUNCTIONS (baselink)
9370 = build_nt (TEMPLATE_ID_EXPR,
9371 BASELINK_FUNCTIONS (baselink),
9373 /* Update the conversion operator type. */
9374 BASELINK_OPTYPE (baselink)
9375 = tsubst (optype, args, complain, in_decl);
9378 object_type = current_class_type;
9379 return adjust_result_of_qualified_name_lookup (baselink,
9384 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
9385 true if the qualified-id will be a postfix-expression in-and-of
9386 itself; false if more of the postfix-expression follows the
9387 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
9391 tsubst_qualified_id (tree qualified_id, tree args,
9392 tsubst_flags_t complain, tree in_decl,
9393 bool done, bool address_p)
9401 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
9403 /* Figure out what name to look up. */
9404 name = TREE_OPERAND (qualified_id, 1);
9405 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
9408 template_args = TREE_OPERAND (name, 1);
9410 template_args = tsubst_template_args (template_args, args,
9412 name = TREE_OPERAND (name, 0);
9416 is_template = false;
9417 template_args = NULL_TREE;
9420 /* Substitute into the qualifying scope. When there are no ARGS, we
9421 are just trying to simplify a non-dependent expression. In that
9422 case the qualifying scope may be dependent, and, in any case,
9423 substituting will not help. */
9424 scope = TREE_OPERAND (qualified_id, 0);
9427 scope = tsubst (scope, args, complain, in_decl);
9428 expr = tsubst_copy (name, args, complain, in_decl);
9433 if (dependent_type_p (scope))
9434 return build_qualified_name (/*type=*/NULL_TREE,
9436 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
9438 if (!BASELINK_P (name) && !DECL_P (expr))
9440 if (TREE_CODE (expr) == BIT_NOT_EXPR)
9441 /* If this were actually a destructor call, it would have been
9442 parsed as such by the parser. */
9443 expr = error_mark_node;
9445 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
9446 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
9447 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
9449 if (complain & tf_error)
9451 error ("dependent-name %qE is parsed as a non-type, but "
9452 "instantiation yields a type", qualified_id);
9453 inform ("say %<typename %E%> if a type is meant", qualified_id);
9455 return error_mark_node;
9461 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
9463 /* Remember that there was a reference to this entity. */
9467 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
9469 if (complain & tf_error)
9470 qualified_name_lookup_error (scope,
9471 TREE_OPERAND (qualified_id, 1),
9473 return error_mark_node;
9477 expr = lookup_template_function (expr, template_args);
9479 if (expr == error_mark_node && complain & tf_error)
9480 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
9482 else if (TYPE_P (scope))
9484 expr = (adjust_result_of_qualified_name_lookup
9485 (expr, scope, current_class_type));
9486 expr = (finish_qualified_id_expr
9487 (scope, expr, done, address_p,
9488 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
9489 /*template_arg_p=*/false));
9492 /* Expressions do not generally have reference type. */
9493 if (TREE_CODE (expr) != SCOPE_REF
9494 /* However, if we're about to form a pointer-to-member, we just
9495 want the referenced member referenced. */
9496 && TREE_CODE (expr) != OFFSET_REF)
9497 expr = convert_from_reference (expr);
9502 /* Like tsubst, but deals with expressions. This function just replaces
9503 template parms; to finish processing the resultant expression, use
9507 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9509 enum tree_code code;
9512 if (t == NULL_TREE || t == error_mark_node)
9515 code = TREE_CODE (t);
9520 r = retrieve_local_specialization (t);
9521 gcc_assert (r != NULL);
9522 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
9523 r = ARGUMENT_PACK_SELECT_ARG (r);
9532 if (DECL_TEMPLATE_PARM_P (t))
9533 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
9534 /* There is no need to substitute into namespace-scope
9536 if (DECL_NAMESPACE_SCOPE_P (t))
9538 /* If ARGS is NULL, then T is known to be non-dependent. */
9539 if (args == NULL_TREE)
9540 return integral_constant_value (t);
9542 /* Unfortunately, we cannot just call lookup_name here.
9545 template <int I> int f() {
9547 struct S { void g() { E e = a; } };
9550 When we instantiate f<7>::S::g(), say, lookup_name is not
9551 clever enough to find f<7>::a. */
9553 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
9554 /*entering_scope=*/0);
9556 for (v = TYPE_VALUES (enum_type);
9559 if (TREE_PURPOSE (v) == DECL_NAME (t))
9560 return TREE_VALUE (v);
9562 /* We didn't find the name. That should never happen; if
9563 name-lookup found it during preliminary parsing, we
9564 should find it again here during instantiation. */
9570 if (DECL_CONTEXT (t))
9574 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
9575 /*entering_scope=*/1);
9576 if (ctx != DECL_CONTEXT (t))
9578 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
9581 if (complain & tf_error)
9582 error ("using invalid field %qD", t);
9583 return error_mark_node;
9593 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
9594 || local_variable_p (t))
9595 t = tsubst (t, args, complain, in_decl);
9600 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
9603 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9604 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
9605 args, complain, in_decl);
9606 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
9607 return tsubst (t, args, complain, in_decl);
9608 else if (DECL_CLASS_SCOPE_P (t)
9609 && uses_template_parms (DECL_CONTEXT (t)))
9611 /* Template template argument like the following example need
9614 template <template <class> class TT> struct C {};
9615 template <class T> struct D {
9616 template <class U> struct E {};
9621 We are processing the template argument `E' in #1 for
9622 the template instantiation #2. Originally, `E' is a
9623 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
9624 have to substitute this with one having context `D<int>'. */
9626 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
9627 return lookup_field (context, DECL_NAME(t), 0, false);
9630 /* Ordinary template template argument. */
9634 case REINTERPRET_CAST_EXPR:
9635 case CONST_CAST_EXPR:
9636 case STATIC_CAST_EXPR:
9637 case DYNAMIC_CAST_EXPR:
9640 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
9641 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
9644 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
9646 /* We only want to compute the number of arguments. */
9647 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
9649 if (expanded == error_mark_node)
9650 return error_mark_node;
9651 return build_int_cst (size_type_node, TREE_VEC_LENGTH (expanded));
9657 case TRUTH_NOT_EXPR:
9660 case UNARY_PLUS_EXPR: /* Unary + */
9668 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
9669 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
9676 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
9677 name = TREE_OPERAND (t, 1);
9678 if (TREE_CODE (name) == BIT_NOT_EXPR)
9680 name = tsubst_copy (TREE_OPERAND (name, 0), args,
9682 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
9684 else if (TREE_CODE (name) == SCOPE_REF
9685 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
9687 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
9689 name = TREE_OPERAND (name, 1);
9690 name = tsubst_copy (TREE_OPERAND (name, 0), args,
9692 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
9693 name = build_qualified_name (/*type=*/NULL_TREE,
9695 /*template_p=*/false);
9697 else if (TREE_CODE (name) == BASELINK)
9698 name = tsubst_baselink (name,
9699 non_reference (TREE_TYPE (object)),
9703 name = tsubst_copy (name, args, complain, in_decl);
9704 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
9710 case TRUNC_DIV_EXPR:
9712 case FLOOR_DIV_EXPR:
9713 case ROUND_DIV_EXPR:
9714 case EXACT_DIV_EXPR:
9718 case TRUNC_MOD_EXPR:
9719 case FLOOR_MOD_EXPR:
9720 case TRUTH_ANDIF_EXPR:
9721 case TRUTH_ORIF_EXPR:
9722 case TRUTH_AND_EXPR:
9739 case PREDECREMENT_EXPR:
9740 case PREINCREMENT_EXPR:
9741 case POSTDECREMENT_EXPR:
9742 case POSTINCREMENT_EXPR:
9744 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
9745 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
9748 return build_qualified_name (/*type=*/NULL_TREE,
9749 tsubst_copy (TREE_OPERAND (t, 0),
9750 args, complain, in_decl),
9751 tsubst_copy (TREE_OPERAND (t, 1),
9752 args, complain, in_decl),
9753 QUALIFIED_NAME_IS_TEMPLATE (t));
9758 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
9759 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
9760 NULL_TREE, NULL_TREE);
9764 int n = VL_EXP_OPERAND_LENGTH (t);
9765 tree result = build_vl_exp (CALL_EXPR, n);
9767 for (i = 0; i < n; i++)
9768 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
9775 case PSEUDO_DTOR_EXPR:
9778 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
9779 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
9780 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
9781 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
9788 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
9789 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
9790 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
9791 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
9798 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
9799 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
9800 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
9801 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
9805 case TEMPLATE_ID_EXPR:
9807 /* Substituted template arguments */
9808 tree fn = TREE_OPERAND (t, 0);
9809 tree targs = TREE_OPERAND (t, 1);
9811 fn = tsubst_copy (fn, args, complain, in_decl);
9813 targs = tsubst_template_args (targs, args, complain, in_decl);
9815 return lookup_template_function (fn, targs);
9820 tree purpose, value, chain;
9822 if (t == void_list_node)
9825 purpose = TREE_PURPOSE (t);
9827 purpose = tsubst_copy (purpose, args, complain, in_decl);
9828 value = TREE_VALUE (t);
9830 value = tsubst_copy (value, args, complain, in_decl);
9831 chain = TREE_CHAIN (t);
9832 if (chain && chain != void_type_node)
9833 chain = tsubst_copy (chain, args, complain, in_decl);
9834 if (purpose == TREE_PURPOSE (t)
9835 && value == TREE_VALUE (t)
9836 && chain == TREE_CHAIN (t))
9838 return tree_cons (purpose, value, chain);
9845 case TEMPLATE_TYPE_PARM:
9846 case TEMPLATE_TEMPLATE_PARM:
9847 case BOUND_TEMPLATE_TEMPLATE_PARM:
9848 case TEMPLATE_PARM_INDEX:
9850 case REFERENCE_TYPE:
9856 case UNBOUND_CLASS_TEMPLATE:
9860 return tsubst (t, args, complain, in_decl);
9862 case IDENTIFIER_NODE:
9863 if (IDENTIFIER_TYPENAME_P (t))
9865 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9866 return mangle_conv_op_name_for_type (new_type);
9872 /* This is handled by tsubst_copy_and_build. */
9876 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
9878 tsubst (TREE_TYPE (t), args, complain, in_decl));
9880 case CLEANUP_POINT_EXPR:
9881 /* We shouldn't have built any of these during initial template
9882 generation. Instead, they should be built during instantiation
9883 in response to the saved STMT_IS_FULL_EXPR_P setting. */
9887 mark_used (TREE_OPERAND (t, 1));
9890 case EXPR_PACK_EXPANSION:
9891 error ("invalid use of pack expansion expression");
9892 return error_mark_node;
9894 case NONTYPE_ARGUMENT_PACK:
9895 error ("use %<...%> to expand argument pack");
9896 return error_mark_node;
9903 /* Like tsubst_copy, but specifically for OpenMP clauses. */
9906 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
9909 tree new_clauses = NULL, nc, oc;
9911 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
9913 nc = copy_node (oc);
9914 OMP_CLAUSE_CHAIN (nc) = new_clauses;
9917 switch (OMP_CLAUSE_CODE (nc))
9919 case OMP_CLAUSE_PRIVATE:
9920 case OMP_CLAUSE_SHARED:
9921 case OMP_CLAUSE_FIRSTPRIVATE:
9922 case OMP_CLAUSE_LASTPRIVATE:
9923 case OMP_CLAUSE_REDUCTION:
9924 case OMP_CLAUSE_COPYIN:
9925 case OMP_CLAUSE_COPYPRIVATE:
9927 case OMP_CLAUSE_NUM_THREADS:
9928 case OMP_CLAUSE_SCHEDULE:
9929 OMP_CLAUSE_OPERAND (nc, 0)
9930 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
9931 in_decl, /*integral_constant_expression_p=*/false);
9933 case OMP_CLAUSE_NOWAIT:
9934 case OMP_CLAUSE_ORDERED:
9935 case OMP_CLAUSE_DEFAULT:
9942 return finish_omp_clauses (nreverse (new_clauses));
9945 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
9948 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
9951 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
9953 tree purpose, value, chain;
9958 if (TREE_CODE (t) != TREE_LIST)
9959 return tsubst_copy_and_build (t, args, complain, in_decl,
9960 /*function_p=*/false,
9961 /*integral_constant_expression_p=*/false);
9963 if (t == void_list_node)
9966 purpose = TREE_PURPOSE (t);
9968 purpose = RECUR (purpose);
9969 value = TREE_VALUE (t);
9971 value = RECUR (value);
9972 chain = TREE_CHAIN (t);
9973 if (chain && chain != void_type_node)
9974 chain = RECUR (chain);
9975 return tree_cons (purpose, value, chain);
9979 /* Like tsubst_copy for expressions, etc. but also does semantic
9983 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
9984 bool integral_constant_expression_p)
9986 #define RECUR(NODE) \
9987 tsubst_expr ((NODE), args, complain, in_decl, \
9988 integral_constant_expression_p)
9992 if (t == NULL_TREE || t == error_mark_node)
9995 if (EXPR_HAS_LOCATION (t))
9996 input_location = EXPR_LOCATION (t);
9997 if (STATEMENT_CODE_P (TREE_CODE (t)))
9998 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
10000 switch (TREE_CODE (t))
10002 case STATEMENT_LIST:
10004 tree_stmt_iterator i;
10005 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
10006 RECUR (tsi_stmt (i));
10010 case CTOR_INITIALIZER:
10011 finish_mem_initializers (tsubst_initializer_list
10012 (TREE_OPERAND (t, 0), args));
10016 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
10020 tmp = RECUR (EXPR_STMT_EXPR (t));
10021 if (EXPR_STMT_STMT_EXPR_RESULT (t))
10022 finish_stmt_expr_expr (tmp, cur_stmt_expr);
10024 finish_expr_stmt (tmp);
10028 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
10036 decl = DECL_EXPR_DECL (t);
10037 if (TREE_CODE (decl) == LABEL_DECL)
10038 finish_label_decl (DECL_NAME (decl));
10039 else if (TREE_CODE (decl) == USING_DECL)
10041 tree scope = USING_DECL_SCOPE (decl);
10042 tree name = DECL_NAME (decl);
10045 scope = RECUR (scope);
10046 decl = lookup_qualified_name (scope, name,
10047 /*is_type_p=*/false,
10048 /*complain=*/false);
10049 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
10050 qualified_name_lookup_error (scope, name, decl);
10052 do_local_using_decl (decl, scope, name);
10056 init = DECL_INITIAL (decl);
10057 decl = tsubst (decl, args, complain, in_decl);
10058 if (decl != error_mark_node)
10060 /* By marking the declaration as instantiated, we avoid
10061 trying to instantiate it. Since instantiate_decl can't
10062 handle local variables, and since we've already done
10063 all that needs to be done, that's the right thing to
10065 if (TREE_CODE (decl) == VAR_DECL)
10066 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
10067 if (TREE_CODE (decl) == VAR_DECL
10068 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
10069 /* Anonymous aggregates are a special case. */
10070 finish_anon_union (decl);
10073 maybe_push_decl (decl);
10074 if (TREE_CODE (decl) == VAR_DECL
10075 && DECL_PRETTY_FUNCTION_P (decl))
10077 /* For __PRETTY_FUNCTION__ we have to adjust the
10079 const char *const name
10080 = cxx_printable_name (current_function_decl, 2);
10081 init = cp_fname_init (name, &TREE_TYPE (decl));
10085 tree t = RECUR (init);
10088 /* If we had an initializer but it
10089 instantiated to nothing,
10090 value-initialize the object. This will
10091 only occur when the initializer was a
10092 pack expansion where the parameter packs
10093 used in that expansion were of length
10095 init = build_default_init (TREE_TYPE (decl),
10101 finish_decl (decl, init, NULL_TREE);
10106 /* A DECL_EXPR can also be used as an expression, in the condition
10107 clause of an if/for/while construct. */
10112 stmt = begin_for_stmt ();
10113 RECUR (FOR_INIT_STMT (t));
10114 finish_for_init_stmt (stmt);
10115 tmp = RECUR (FOR_COND (t));
10116 finish_for_cond (tmp, stmt);
10117 tmp = RECUR (FOR_EXPR (t));
10118 finish_for_expr (tmp, stmt);
10119 RECUR (FOR_BODY (t));
10120 finish_for_stmt (stmt);
10124 stmt = begin_while_stmt ();
10125 tmp = RECUR (WHILE_COND (t));
10126 finish_while_stmt_cond (tmp, stmt);
10127 RECUR (WHILE_BODY (t));
10128 finish_while_stmt (stmt);
10132 stmt = begin_do_stmt ();
10133 RECUR (DO_BODY (t));
10134 finish_do_body (stmt);
10135 tmp = RECUR (DO_COND (t));
10136 finish_do_stmt (tmp, stmt);
10140 stmt = begin_if_stmt ();
10141 tmp = RECUR (IF_COND (t));
10142 finish_if_stmt_cond (tmp, stmt);
10143 RECUR (THEN_CLAUSE (t));
10144 finish_then_clause (stmt);
10146 if (ELSE_CLAUSE (t))
10148 begin_else_clause (stmt);
10149 RECUR (ELSE_CLAUSE (t));
10150 finish_else_clause (stmt);
10153 finish_if_stmt (stmt);
10157 if (BIND_EXPR_BODY_BLOCK (t))
10158 stmt = begin_function_body ();
10160 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
10161 ? BCS_TRY_BLOCK : 0);
10163 RECUR (BIND_EXPR_BODY (t));
10165 if (BIND_EXPR_BODY_BLOCK (t))
10166 finish_function_body (stmt);
10168 finish_compound_stmt (stmt);
10172 finish_break_stmt ();
10175 case CONTINUE_STMT:
10176 finish_continue_stmt ();
10180 stmt = begin_switch_stmt ();
10181 tmp = RECUR (SWITCH_STMT_COND (t));
10182 finish_switch_cond (tmp, stmt);
10183 RECUR (SWITCH_STMT_BODY (t));
10184 finish_switch_stmt (stmt);
10187 case CASE_LABEL_EXPR:
10188 finish_case_label (RECUR (CASE_LOW (t)),
10189 RECUR (CASE_HIGH (t)));
10193 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
10197 tmp = GOTO_DESTINATION (t);
10198 if (TREE_CODE (tmp) != LABEL_DECL)
10199 /* Computed goto's must be tsubst'd into. On the other hand,
10200 non-computed gotos must not be; the identifier in question
10201 will have no binding. */
10204 tmp = DECL_NAME (tmp);
10205 finish_goto_stmt (tmp);
10209 tmp = finish_asm_stmt
10210 (ASM_VOLATILE_P (t),
10211 RECUR (ASM_STRING (t)),
10212 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
10213 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
10214 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl));
10216 tree asm_expr = tmp;
10217 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
10218 asm_expr = TREE_OPERAND (asm_expr, 0);
10219 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
10226 stmt = begin_try_block ();
10227 RECUR (TRY_STMTS (t));
10228 finish_cleanup_try_block (stmt);
10229 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
10233 tree compound_stmt = NULL_TREE;
10235 if (FN_TRY_BLOCK_P (t))
10236 stmt = begin_function_try_block (&compound_stmt);
10238 stmt = begin_try_block ();
10240 RECUR (TRY_STMTS (t));
10242 if (FN_TRY_BLOCK_P (t))
10243 finish_function_try_block (stmt);
10245 finish_try_block (stmt);
10247 RECUR (TRY_HANDLERS (t));
10248 if (FN_TRY_BLOCK_P (t))
10249 finish_function_handler_sequence (stmt, compound_stmt);
10251 finish_handler_sequence (stmt);
10257 tree decl = HANDLER_PARMS (t);
10261 decl = tsubst (decl, args, complain, in_decl);
10262 /* Prevent instantiate_decl from trying to instantiate
10263 this variable. We've already done all that needs to be
10265 if (decl != error_mark_node)
10266 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
10268 stmt = begin_handler ();
10269 finish_handler_parms (decl, stmt);
10270 RECUR (HANDLER_BODY (t));
10271 finish_handler (stmt);
10276 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
10279 case STATIC_ASSERT:
10282 tsubst_expr (STATIC_ASSERT_CONDITION (t),
10285 /*integral_constant_expression_p=*/true);
10286 finish_static_assert (condition,
10287 STATIC_ASSERT_MESSAGE (t),
10288 STATIC_ASSERT_SOURCE_LOCATION (t),
10289 /*member_p=*/false);
10294 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
10295 args, complain, in_decl);
10296 stmt = begin_omp_parallel ();
10297 RECUR (OMP_PARALLEL_BODY (t));
10298 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
10299 = OMP_PARALLEL_COMBINED (t);
10304 tree clauses, decl, init, cond, incr, body, pre_body;
10306 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
10307 args, complain, in_decl);
10308 init = OMP_FOR_INIT (t);
10309 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
10310 decl = RECUR (TREE_OPERAND (init, 0));
10311 init = RECUR (TREE_OPERAND (init, 1));
10312 cond = RECUR (OMP_FOR_COND (t));
10313 incr = RECUR (OMP_FOR_INCR (t));
10315 stmt = begin_omp_structured_block ();
10317 pre_body = push_stmt_list ();
10318 RECUR (OMP_FOR_PRE_BODY (t));
10319 pre_body = pop_stmt_list (pre_body);
10321 body = push_stmt_list ();
10322 RECUR (OMP_FOR_BODY (t));
10323 body = pop_stmt_list (body);
10325 t = finish_omp_for (EXPR_LOCATION (t), decl, init, cond, incr, body,
10328 OMP_FOR_CLAUSES (t) = clauses;
10330 add_stmt (finish_omp_structured_block (stmt));
10336 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
10337 stmt = push_stmt_list ();
10338 RECUR (OMP_BODY (t));
10339 stmt = pop_stmt_list (stmt);
10342 OMP_BODY (t) = stmt;
10343 OMP_CLAUSES (t) = tmp;
10351 stmt = push_stmt_list ();
10352 RECUR (OMP_BODY (t));
10353 stmt = pop_stmt_list (stmt);
10356 OMP_BODY (t) = stmt;
10361 if (OMP_ATOMIC_DEPENDENT_P (t))
10363 tree op1 = TREE_OPERAND (t, 1);
10364 tree lhs = RECUR (TREE_OPERAND (op1, 0));
10365 tree rhs = RECUR (TREE_OPERAND (op1, 1));
10366 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
10370 case EXPR_PACK_EXPANSION:
10371 error ("invalid use of pack expansion expression");
10372 return error_mark_node;
10374 case NONTYPE_ARGUMENT_PACK:
10375 error ("use %<...%> to expand argument pack");
10376 return error_mark_node;
10379 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
10381 return tsubst_copy_and_build (t, args, complain, in_decl,
10382 /*function_p=*/false,
10383 integral_constant_expression_p);
10390 /* T is a postfix-expression that is not being used in a function
10391 call. Return the substituted version of T. */
10394 tsubst_non_call_postfix_expression (tree t, tree args,
10395 tsubst_flags_t complain,
10398 if (TREE_CODE (t) == SCOPE_REF)
10399 t = tsubst_qualified_id (t, args, complain, in_decl,
10400 /*done=*/false, /*address_p=*/false);
10402 t = tsubst_copy_and_build (t, args, complain, in_decl,
10403 /*function_p=*/false,
10404 /*integral_constant_expression_p=*/false);
10409 /* Like tsubst but deals with expressions and performs semantic
10410 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
10413 tsubst_copy_and_build (tree t,
10415 tsubst_flags_t complain,
10418 bool integral_constant_expression_p)
10420 #define RECUR(NODE) \
10421 tsubst_copy_and_build (NODE, args, complain, in_decl, \
10422 /*function_p=*/false, \
10423 integral_constant_expression_p)
10427 if (t == NULL_TREE || t == error_mark_node)
10430 switch (TREE_CODE (t))
10434 /* Fall through. */
10435 case IDENTIFIER_NODE:
10439 bool non_integral_constant_expression_p;
10440 const char *error_msg;
10442 if (IDENTIFIER_TYPENAME_P (t))
10444 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10445 t = mangle_conv_op_name_for_type (new_type);
10448 /* Look up the name. */
10449 decl = lookup_name (t);
10451 /* By convention, expressions use ERROR_MARK_NODE to indicate
10452 failure, not NULL_TREE. */
10453 if (decl == NULL_TREE)
10454 decl = error_mark_node;
10456 decl = finish_id_expression (t, decl, NULL_TREE,
10458 integral_constant_expression_p,
10459 /*allow_non_integral_constant_expression_p=*/false,
10460 &non_integral_constant_expression_p,
10461 /*template_p=*/false,
10463 /*address_p=*/false,
10464 /*template_arg_p=*/false,
10468 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
10469 decl = unqualified_name_lookup_error (decl);
10473 case TEMPLATE_ID_EXPR:
10476 tree template = RECUR (TREE_OPERAND (t, 0));
10477 tree targs = TREE_OPERAND (t, 1);
10480 targs = tsubst_template_args (targs, args, complain, in_decl);
10482 if (TREE_CODE (template) == COMPONENT_REF)
10484 object = TREE_OPERAND (template, 0);
10485 template = TREE_OPERAND (template, 1);
10488 object = NULL_TREE;
10489 template = lookup_template_function (template, targs);
10492 return build3 (COMPONENT_REF, TREE_TYPE (template),
10493 object, template, NULL_TREE);
10495 return baselink_for_fns (template);
10500 tree r = RECUR (TREE_OPERAND (t, 0));
10502 if (REFERENCE_REF_P (t))
10504 /* A type conversion to reference type will be enclosed in
10505 such an indirect ref, but the substitution of the cast
10506 will have also added such an indirect ref. */
10507 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
10508 r = convert_from_reference (r);
10511 r = build_x_indirect_ref (r, "unary *");
10517 (tsubst (TREE_TYPE (t), args, complain, in_decl),
10518 RECUR (TREE_OPERAND (t, 0)));
10521 case REINTERPRET_CAST_EXPR:
10522 case CONST_CAST_EXPR:
10523 case DYNAMIC_CAST_EXPR:
10524 case STATIC_CAST_EXPR:
10529 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10530 if (integral_constant_expression_p
10531 && !cast_valid_in_integral_constant_expression_p (type))
10533 error ("a cast to a type other than an integral or "
10534 "enumeration type cannot appear in a constant-expression");
10535 return error_mark_node;
10538 op = RECUR (TREE_OPERAND (t, 0));
10540 switch (TREE_CODE (t))
10543 return build_functional_cast (type, op);
10544 case REINTERPRET_CAST_EXPR:
10545 return build_reinterpret_cast (type, op);
10546 case CONST_CAST_EXPR:
10547 return build_const_cast (type, op);
10548 case DYNAMIC_CAST_EXPR:
10549 return build_dynamic_cast (type, op);
10550 case STATIC_CAST_EXPR:
10551 return build_static_cast (type, op);
10553 gcc_unreachable ();
10557 case POSTDECREMENT_EXPR:
10558 case POSTINCREMENT_EXPR:
10559 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
10560 args, complain, in_decl);
10561 return build_x_unary_op (TREE_CODE (t), op1);
10563 case PREDECREMENT_EXPR:
10564 case PREINCREMENT_EXPR:
10568 case TRUTH_NOT_EXPR:
10569 case UNARY_PLUS_EXPR: /* Unary + */
10570 case REALPART_EXPR:
10571 case IMAGPART_EXPR:
10572 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
10575 op1 = TREE_OPERAND (t, 0);
10576 if (TREE_CODE (op1) == SCOPE_REF)
10577 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
10578 /*done=*/true, /*address_p=*/true);
10580 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
10582 if (TREE_CODE (op1) == LABEL_DECL)
10583 return finish_label_address_expr (DECL_NAME (op1));
10584 return build_x_unary_op (ADDR_EXPR, op1);
10589 case TRUNC_DIV_EXPR:
10590 case CEIL_DIV_EXPR:
10591 case FLOOR_DIV_EXPR:
10592 case ROUND_DIV_EXPR:
10593 case EXACT_DIV_EXPR:
10597 case TRUNC_MOD_EXPR:
10598 case FLOOR_MOD_EXPR:
10599 case TRUTH_ANDIF_EXPR:
10600 case TRUTH_ORIF_EXPR:
10601 case TRUTH_AND_EXPR:
10602 case TRUTH_OR_EXPR:
10617 return build_x_binary_op
10619 RECUR (TREE_OPERAND (t, 0)),
10620 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
10622 : TREE_CODE (TREE_OPERAND (t, 0))),
10623 RECUR (TREE_OPERAND (t, 1)),
10624 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
10626 : TREE_CODE (TREE_OPERAND (t, 1))),
10627 /*overloaded_p=*/NULL);
10630 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
10631 /*address_p=*/false);
10633 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
10634 args, complain, in_decl);
10635 return build_x_binary_op (ARRAY_REF, op1,
10636 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
10638 : TREE_CODE (TREE_OPERAND (t, 0))),
10639 RECUR (TREE_OPERAND (t, 1)),
10640 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
10642 : TREE_CODE (TREE_OPERAND (t, 1))),
10643 /*overloaded_p=*/NULL);
10646 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
10648 /* We only want to compute the number of arguments. */
10649 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
10650 complain, in_decl);
10651 if (expanded == error_mark_node)
10652 return error_mark_node;
10653 return build_int_cst (size_type_node, TREE_VEC_LENGTH (expanded));
10658 op1 = TREE_OPERAND (t, 0);
10661 /* When there are no ARGS, we are trying to evaluate a
10662 non-dependent expression from the parser. Trying to do
10663 the substitutions may not work. */
10665 op1 = TREE_TYPE (op1);
10670 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
10671 /*function_p=*/false,
10672 /*integral_constant_expression_p=*/false);
10676 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
10678 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
10682 tree r = build_x_modify_expr
10683 (RECUR (TREE_OPERAND (t, 0)),
10684 TREE_CODE (TREE_OPERAND (t, 1)),
10685 RECUR (TREE_OPERAND (t, 2)));
10686 /* TREE_NO_WARNING must be set if either the expression was
10687 parenthesized or it uses an operator such as >>= rather
10688 than plain assignment. In the former case, it was already
10689 set and must be copied. In the latter case,
10690 build_x_modify_expr sets it and it must not be reset
10692 if (TREE_NO_WARNING (t))
10693 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
10698 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
10699 args, complain, in_decl);
10700 /* Remember that there was a reference to this entity. */
10703 return build_x_arrow (op1);
10707 tree init = RECUR (TREE_OPERAND (t, 3));
10709 if (TREE_OPERAND (t, 3) && !init)
10710 /* If there was an initializer in the the original tree, but
10711 it instantiated to an empty list, then we should pass on
10712 VOID_ZERO_NODE to tell build_new that it was an empty
10713 initializer () rather than no initializer. This can only
10714 happen when the initializer is a pack expansion whose
10715 parameter packs are of length zero. */
10716 init = void_zero_node;
10719 (RECUR (TREE_OPERAND (t, 0)),
10720 RECUR (TREE_OPERAND (t, 1)),
10721 RECUR (TREE_OPERAND (t, 2)),
10723 NEW_EXPR_USE_GLOBAL (t));
10727 return delete_sanity
10728 (RECUR (TREE_OPERAND (t, 0)),
10729 RECUR (TREE_OPERAND (t, 1)),
10730 DELETE_EXPR_USE_VEC (t),
10731 DELETE_EXPR_USE_GLOBAL (t));
10733 case COMPOUND_EXPR:
10734 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
10735 RECUR (TREE_OPERAND (t, 1)));
10744 function = CALL_EXPR_FN (t);
10745 /* When we parsed the expression, we determined whether or
10746 not Koenig lookup should be performed. */
10747 koenig_p = KOENIG_LOOKUP_P (t);
10748 if (TREE_CODE (function) == SCOPE_REF)
10750 qualified_p = true;
10751 function = tsubst_qualified_id (function, args, complain, in_decl,
10753 /*address_p=*/false);
10757 if (TREE_CODE (function) == COMPONENT_REF)
10759 tree op = TREE_OPERAND (function, 1);
10761 qualified_p = (TREE_CODE (op) == SCOPE_REF
10762 || (BASELINK_P (op)
10763 && BASELINK_QUALIFIED_P (op)));
10766 qualified_p = false;
10768 function = tsubst_copy_and_build (function, args, complain,
10771 integral_constant_expression_p);
10773 if (BASELINK_P (function))
10774 qualified_p = true;
10777 /* FIXME: Rewrite this so as not to construct an arglist. */
10778 call_args = RECUR (CALL_EXPR_ARGS (t));
10780 /* We do not perform argument-dependent lookup if normal
10781 lookup finds a non-function, in accordance with the
10782 expected resolution of DR 218. */
10784 && ((is_overloaded_fn (function)
10785 /* If lookup found a member function, the Koenig lookup is
10786 not appropriate, even if an unqualified-name was used
10787 to denote the function. */
10788 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
10789 || TREE_CODE (function) == IDENTIFIER_NODE))
10790 function = perform_koenig_lookup (function, call_args);
10792 if (TREE_CODE (function) == IDENTIFIER_NODE)
10794 unqualified_name_lookup_error (function);
10795 return error_mark_node;
10798 /* Remember that there was a reference to this entity. */
10799 if (DECL_P (function))
10800 mark_used (function);
10802 if (TREE_CODE (function) == OFFSET_REF)
10803 return build_offset_ref_call_from_tree (function, call_args);
10804 if (TREE_CODE (function) == COMPONENT_REF)
10806 if (!BASELINK_P (TREE_OPERAND (function, 1)))
10807 return finish_call_expr (function, call_args,
10808 /*disallow_virtual=*/false,
10809 /*koenig_p=*/false);
10811 return (build_new_method_call
10812 (TREE_OPERAND (function, 0),
10813 TREE_OPERAND (function, 1),
10814 call_args, NULL_TREE,
10815 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
10818 return finish_call_expr (function, call_args,
10819 /*disallow_virtual=*/qualified_p,
10824 return build_x_conditional_expr
10825 (RECUR (TREE_OPERAND (t, 0)),
10826 RECUR (TREE_OPERAND (t, 1)),
10827 RECUR (TREE_OPERAND (t, 2)));
10829 case PSEUDO_DTOR_EXPR:
10830 return finish_pseudo_destructor_expr
10831 (RECUR (TREE_OPERAND (t, 0)),
10832 RECUR (TREE_OPERAND (t, 1)),
10833 RECUR (TREE_OPERAND (t, 2)));
10837 tree purpose, value, chain;
10839 if (t == void_list_node)
10842 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
10843 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
10845 /* We have pack expansions, so expand those and
10846 create a new list out of it. */
10847 tree purposevec = NULL_TREE;
10848 tree valuevec = NULL_TREE;
10852 /* Expand the argument expressions. */
10853 if (TREE_PURPOSE (t))
10854 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
10855 complain, in_decl);
10856 if (TREE_VALUE (t))
10857 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
10858 complain, in_decl);
10860 /* Build the rest of the list. */
10861 chain = TREE_CHAIN (t);
10862 if (chain && chain != void_type_node)
10863 chain = RECUR (chain);
10865 /* Determine the number of arguments. */
10866 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
10868 len = TREE_VEC_LENGTH (purposevec);
10869 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
10871 else if (TREE_CODE (valuevec) == TREE_VEC)
10872 len = TREE_VEC_LENGTH (valuevec);
10875 /* Since we only performed a partial substitution into
10876 the argument pack, we only return a single list
10878 if (purposevec == TREE_PURPOSE (t)
10879 && valuevec == TREE_VALUE (t)
10880 && chain == TREE_CHAIN (t))
10883 return tree_cons (purposevec, valuevec, chain);
10886 /* Convert the argument vectors into a TREE_LIST */
10890 /* Grab the Ith values. */
10892 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
10895 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
10898 /* Build the list (backwards). */
10899 chain = tree_cons (purpose, value, chain);
10905 purpose = TREE_PURPOSE (t);
10907 purpose = RECUR (purpose);
10908 value = TREE_VALUE (t);
10910 value = RECUR (value);
10911 chain = TREE_CHAIN (t);
10912 if (chain && chain != void_type_node)
10913 chain = RECUR (chain);
10914 if (purpose == TREE_PURPOSE (t)
10915 && value == TREE_VALUE (t)
10916 && chain == TREE_CHAIN (t))
10918 return tree_cons (purpose, value, chain);
10921 case COMPONENT_REF:
10927 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
10928 args, complain, in_decl);
10929 /* Remember that there was a reference to this entity. */
10930 if (DECL_P (object))
10931 mark_used (object);
10932 object_type = TREE_TYPE (object);
10934 member = TREE_OPERAND (t, 1);
10935 if (BASELINK_P (member))
10936 member = tsubst_baselink (member,
10937 non_reference (TREE_TYPE (object)),
10938 args, complain, in_decl);
10940 member = tsubst_copy (member, args, complain, in_decl);
10941 if (member == error_mark_node)
10942 return error_mark_node;
10944 if (object_type && !CLASS_TYPE_P (object_type))
10946 if (TREE_CODE (member) == BIT_NOT_EXPR)
10947 return finish_pseudo_destructor_expr (object,
10950 else if (TREE_CODE (member) == SCOPE_REF
10951 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
10952 return finish_pseudo_destructor_expr (object,
10956 else if (TREE_CODE (member) == SCOPE_REF
10957 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
10962 /* Lookup the template functions now that we know what the
10964 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
10965 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
10966 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
10967 /*is_type_p=*/false,
10968 /*complain=*/false);
10969 if (BASELINK_P (member))
10971 BASELINK_FUNCTIONS (member)
10972 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
10974 member = (adjust_result_of_qualified_name_lookup
10975 (member, BINFO_TYPE (BASELINK_BINFO (member)),
10980 qualified_name_lookup_error (object_type, tmpl, member);
10981 return error_mark_node;
10984 else if (TREE_CODE (member) == SCOPE_REF
10985 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
10986 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
10988 if (complain & tf_error)
10990 if (TYPE_P (TREE_OPERAND (member, 0)))
10991 error ("%qT is not a class or namespace",
10992 TREE_OPERAND (member, 0));
10994 error ("%qD is not a class or namespace",
10995 TREE_OPERAND (member, 0));
10997 return error_mark_node;
10999 else if (TREE_CODE (member) == FIELD_DECL)
11000 return finish_non_static_data_member (member, object, NULL_TREE);
11002 return finish_class_member_access_expr (object, member,
11003 /*template_p=*/false);
11008 (RECUR (TREE_OPERAND (t, 0)));
11012 VEC(constructor_elt,gc) *n;
11013 constructor_elt *ce;
11014 unsigned HOST_WIDE_INT idx;
11015 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11016 bool process_index_p;
11018 bool need_copy_p = false;
11020 if (type == error_mark_node)
11021 return error_mark_node;
11023 /* digest_init will do the wrong thing if we let it. */
11024 if (type && TYPE_PTRMEMFUNC_P (type))
11027 /* We do not want to process the index of aggregate
11028 initializers as they are identifier nodes which will be
11029 looked up by digest_init. */
11030 process_index_p = !(type && IS_AGGR_TYPE (type));
11032 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
11033 newlen = VEC_length (constructor_elt, n);
11034 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
11036 if (ce->index && process_index_p)
11037 ce->index = RECUR (ce->index);
11039 if (PACK_EXPANSION_P (ce->value))
11041 /* Substitute into the pack expansion. */
11042 ce->value = tsubst_pack_expansion (ce->value, args, complain,
11045 if (ce->value == error_mark_node)
11047 else if (TREE_VEC_LENGTH (ce->value) == 1)
11048 /* Just move the argument into place. */
11049 ce->value = TREE_VEC_ELT (ce->value, 0);
11052 /* Update the length of the final CONSTRUCTOR
11053 arguments vector, and note that we will need to
11055 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
11056 need_copy_p = true;
11060 ce->value = RECUR (ce->value);
11065 VEC(constructor_elt,gc) *old_n = n;
11067 n = VEC_alloc (constructor_elt, gc, newlen);
11068 for (idx = 0; VEC_iterate (constructor_elt, old_n, idx, ce);
11071 if (TREE_CODE (ce->value) == TREE_VEC)
11073 int i, len = TREE_VEC_LENGTH (ce->value);
11074 for (i = 0; i < len; ++i)
11075 CONSTRUCTOR_APPEND_ELT (n, 0,
11076 TREE_VEC_ELT (ce->value, i));
11079 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
11083 if (TREE_HAS_CONSTRUCTOR (t))
11084 return finish_compound_literal (type, n);
11086 return build_constructor (NULL_TREE, n);
11091 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
11092 if (TYPE_P (operand_0))
11093 return get_typeid (operand_0);
11094 return build_typeid (operand_0);
11104 tree r = tsubst_copy (t, args, complain, in_decl);
11106 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
11107 /* If the original type was a reference, we'll be wrapped in
11108 the appropriate INDIRECT_REF. */
11109 r = convert_from_reference (r);
11114 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
11115 tsubst_copy (TREE_TYPE (t), args, complain,
11118 case OFFSETOF_EXPR:
11119 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
11123 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
11124 complain, in_decl);
11126 tree type2 = TRAIT_EXPR_TYPE2 (t);
11128 type2 = tsubst_copy (type2, args, complain, in_decl);
11130 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
11135 tree old_stmt_expr = cur_stmt_expr;
11136 tree stmt_expr = begin_stmt_expr ();
11138 cur_stmt_expr = stmt_expr;
11139 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
11140 integral_constant_expression_p);
11141 stmt_expr = finish_stmt_expr (stmt_expr, false);
11142 cur_stmt_expr = old_stmt_expr;
11148 t = tsubst_copy (t, args, complain, in_decl);
11149 /* As in finish_id_expression, we resolve enumeration constants
11150 to their underlying values. */
11151 if (TREE_CODE (t) == CONST_DECL)
11153 used_types_insert (TREE_TYPE (t));
11154 return DECL_INITIAL (t);
11159 /* Handle Objective-C++ constructs, if appropriate. */
11162 = objcp_tsubst_copy_and_build (t, args, complain,
11163 in_decl, /*function_p=*/false);
11167 return tsubst_copy (t, args, complain, in_decl);
11173 /* Verify that the instantiated ARGS are valid. For type arguments,
11174 make sure that the type's linkage is ok. For non-type arguments,
11175 make sure they are constants if they are integral or enumerations.
11176 Emit an error under control of COMPLAIN, and return TRUE on error. */
11179 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
11181 int ix, len = DECL_NTPARMS (tmpl);
11182 bool result = false;
11184 for (ix = 0; ix != len; ix++)
11186 tree t = TREE_VEC_ELT (args, ix);
11190 /* [basic.link]: A name with no linkage (notably, the name
11191 of a class or enumeration declared in a local scope)
11192 shall not be used to declare an entity with linkage.
11193 This implies that names with no linkage cannot be used as
11194 template arguments. */
11195 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
11199 /* DR 488 makes use of a type with no linkage cause
11200 type deduction to fail. */
11201 if (complain & tf_error)
11203 if (TYPE_ANONYMOUS_P (nt))
11204 error ("%qT is/uses anonymous type", t);
11206 error ("template argument for %qD uses local type %qT",
11211 /* In order to avoid all sorts of complications, we do not
11212 allow variably-modified types as template arguments. */
11213 else if (variably_modified_type_p (t, NULL_TREE))
11215 if (complain & tf_error)
11216 error ("%qT is a variably modified type", t);
11220 /* A non-type argument of integral or enumerated type must be a
11222 else if (TREE_TYPE (t)
11223 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
11224 && !TREE_CONSTANT (t))
11226 if (complain & tf_error)
11227 error ("integral expression %qE is not constant", t);
11231 if (result && (complain & tf_error))
11232 error (" trying to instantiate %qD", tmpl);
11236 /* Instantiate the indicated variable or function template TMPL with
11237 the template arguments in TARG_PTR. */
11240 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
11245 HOST_WIDE_INT saved_processing_template_decl;
11247 if (tmpl == error_mark_node)
11248 return error_mark_node;
11250 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
11252 /* If this function is a clone, handle it specially. */
11253 if (DECL_CLONED_FUNCTION_P (tmpl))
11258 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
11260 if (spec == error_mark_node)
11261 return error_mark_node;
11263 /* Look for the clone. */
11264 FOR_EACH_CLONE (clone, spec)
11265 if (DECL_NAME (clone) == DECL_NAME (tmpl))
11267 /* We should always have found the clone by now. */
11268 gcc_unreachable ();
11272 /* Check to see if we already have this specialization. */
11273 spec = retrieve_specialization (tmpl, targ_ptr,
11274 /*class_specializations_p=*/false);
11275 if (spec != NULL_TREE)
11278 gen_tmpl = most_general_template (tmpl);
11279 if (tmpl != gen_tmpl)
11281 /* The TMPL is a partial instantiation. To get a full set of
11282 arguments we must add the arguments used to perform the
11283 partial instantiation. */
11284 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
11287 /* Check to see if we already have this specialization. */
11288 spec = retrieve_specialization (gen_tmpl, targ_ptr,
11289 /*class_specializations_p=*/false);
11290 if (spec != NULL_TREE)
11294 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
11296 return error_mark_node;
11298 /* We are building a FUNCTION_DECL, during which the access of its
11299 parameters and return types have to be checked. However this
11300 FUNCTION_DECL which is the desired context for access checking
11301 is not built yet. We solve this chicken-and-egg problem by
11302 deferring all checks until we have the FUNCTION_DECL. */
11303 push_deferring_access_checks (dk_deferred);
11305 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
11306 (because, for example, we have encountered a non-dependent
11307 function call in the body of a template function and must now
11308 determine which of several overloaded functions will be called),
11309 within the instantiation itself we are not processing a
11311 saved_processing_template_decl = processing_template_decl;
11312 processing_template_decl = 0;
11313 /* Substitute template parameters to obtain the specialization. */
11314 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
11315 targ_ptr, complain, gen_tmpl);
11316 processing_template_decl = saved_processing_template_decl;
11317 if (fndecl == error_mark_node)
11318 return error_mark_node;
11320 /* Now we know the specialization, compute access previously
11322 push_access_scope (fndecl);
11323 perform_deferred_access_checks ();
11324 pop_access_scope (fndecl);
11325 pop_deferring_access_checks ();
11327 /* The DECL_TI_TEMPLATE should always be the immediate parent
11328 template, not the most general template. */
11329 DECL_TI_TEMPLATE (fndecl) = tmpl;
11331 /* If we've just instantiated the main entry point for a function,
11332 instantiate all the alternate entry points as well. We do this
11333 by cloning the instantiation of the main entry point, not by
11334 instantiating the template clones. */
11335 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
11336 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
11341 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
11342 arguments that are being used when calling it. TARGS is a vector
11343 into which the deduced template arguments are placed.
11345 Return zero for success, 2 for an incomplete match that doesn't resolve
11346 all the types, and 1 for complete failure. An error message will be
11347 printed only for an incomplete match.
11349 If FN is a conversion operator, or we are trying to produce a specific
11350 specialization, RETURN_TYPE is the return type desired.
11352 The EXPLICIT_TARGS are explicit template arguments provided via a
11355 The parameter STRICT is one of:
11358 We are deducing arguments for a function call, as in
11359 [temp.deduct.call].
11362 We are deducing arguments for a conversion function, as in
11363 [temp.deduct.conv].
11366 We are deducing arguments when doing an explicit instantiation
11367 as in [temp.explicit], when determining an explicit specialization
11368 as in [temp.expl.spec], or when taking the address of a function
11369 template, as in [temp.deduct.funcaddr]. */
11372 fn_type_unification (tree fn,
11373 tree explicit_targs,
11377 unification_kind_t strict,
11383 bool incomplete_argument_packs_p = false;
11385 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
11387 fntype = TREE_TYPE (fn);
11388 if (explicit_targs)
11392 The specified template arguments must match the template
11393 parameters in kind (i.e., type, nontype, template), and there
11394 must not be more arguments than there are parameters;
11395 otherwise type deduction fails.
11397 Nontype arguments must match the types of the corresponding
11398 nontype template parameters, or must be convertible to the
11399 types of the corresponding nontype parameters as specified in
11400 _temp.arg.nontype_, otherwise type deduction fails.
11402 All references in the function type of the function template
11403 to the corresponding template parameters are replaced by the
11404 specified template argument values. If a substitution in a
11405 template parameter or in the function type of the function
11406 template results in an invalid type, type deduction fails. */
11407 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
11408 int i, len = TREE_VEC_LENGTH (tparms);
11409 tree converted_args;
11410 bool incomplete = false;
11412 if (explicit_targs == error_mark_node)
11416 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
11417 /*require_all_args=*/false,
11418 /*use_default_args=*/false));
11419 if (converted_args == error_mark_node)
11422 /* Substitute the explicit args into the function type. This is
11423 necessary so that, for instance, explicitly declared function
11424 arguments can match null pointed constants. If we were given
11425 an incomplete set of explicit args, we must not do semantic
11426 processing during substitution as we could create partial
11428 for (i = 0; i < len; i++)
11430 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
11431 bool parameter_pack = false;
11433 /* Dig out the actual parm. */
11434 if (TREE_CODE (parm) == TYPE_DECL
11435 || TREE_CODE (parm) == TEMPLATE_DECL)
11437 parm = TREE_TYPE (parm);
11438 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
11440 else if (TREE_CODE (parm) == PARM_DECL)
11442 parm = DECL_INITIAL (parm);
11443 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
11446 if (parameter_pack)
11450 template_parm_level_and_index (parm, &level, &idx);
11452 /* Mark the argument pack as "incomplete". We could
11453 still deduce more arguments during unification. */
11454 targ = TMPL_ARG (converted_args, level, idx);
11457 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
11458 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
11459 = ARGUMENT_PACK_ARGS (targ);
11462 /* We have some incomplete argument packs. */
11463 incomplete_argument_packs_p = true;
11467 if (incomplete_argument_packs_p)
11468 /* Any substitution is guaranteed to be incomplete if there
11469 are incomplete argument packs, because we can still deduce
11473 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
11475 processing_template_decl += incomplete;
11476 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
11477 processing_template_decl -= incomplete;
11479 if (fntype == error_mark_node)
11482 /* Place the explicitly specified arguments in TARGS. */
11483 for (i = NUM_TMPL_ARGS (converted_args); i--;)
11484 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
11487 /* Never do unification on the 'this' parameter. */
11488 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
11492 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
11493 args = tree_cons (NULL_TREE, return_type, args);
11496 /* We allow incomplete unification without an error message here
11497 because the standard doesn't seem to explicitly prohibit it. Our
11498 callers must be ready to deal with unification failures in any
11500 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
11501 targs, parms, args, /*subr=*/0,
11504 if (result == 0 && incomplete_argument_packs_p)
11506 int i, len = NUM_TMPL_ARGS (targs);
11508 /* Clear the "incomplete" flags on all argument packs. */
11509 for (i = 0; i < len; i++)
11511 tree arg = TREE_VEC_ELT (targs, i);
11512 if (ARGUMENT_PACK_P (arg))
11514 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
11515 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
11521 /* All is well so far. Now, check:
11525 When all template arguments have been deduced, all uses of
11526 template parameters in nondeduced contexts are replaced with
11527 the corresponding deduced argument values. If the
11528 substitution results in an invalid type, as described above,
11529 type deduction fails. */
11530 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
11531 == error_mark_node)
11537 /* Adjust types before performing type deduction, as described in
11538 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
11539 sections are symmetric. PARM is the type of a function parameter
11540 or the return type of the conversion function. ARG is the type of
11541 the argument passed to the call, or the type of the value
11542 initialized with the result of the conversion function.
11543 ARG_EXPR is the original argument expression, which may be null. */
11546 maybe_adjust_types_for_deduction (unification_kind_t strict,
11560 /* Swap PARM and ARG throughout the remainder of this
11561 function; the handling is precisely symmetric since PARM
11562 will initialize ARG rather than vice versa. */
11570 /* There is nothing to do in this case. */
11574 gcc_unreachable ();
11577 if (TREE_CODE (*parm) != REFERENCE_TYPE)
11579 /* [temp.deduct.call]
11581 If P is not a reference type:
11583 --If A is an array type, the pointer type produced by the
11584 array-to-pointer standard conversion (_conv.array_) is
11585 used in place of A for type deduction; otherwise,
11587 --If A is a function type, the pointer type produced by
11588 the function-to-pointer standard conversion
11589 (_conv.func_) is used in place of A for type deduction;
11592 --If A is a cv-qualified type, the top level
11593 cv-qualifiers of A's type are ignored for type
11595 if (TREE_CODE (*arg) == ARRAY_TYPE)
11596 *arg = build_pointer_type (TREE_TYPE (*arg));
11597 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
11598 *arg = build_pointer_type (*arg);
11600 *arg = TYPE_MAIN_VARIANT (*arg);
11603 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
11604 of the form T&&, where T is a template parameter, and the argument
11605 is an lvalue, T is deduced as A& */
11606 if (TREE_CODE (*parm) == REFERENCE_TYPE
11607 && TYPE_REF_IS_RVALUE (*parm)
11608 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
11609 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
11610 && arg_expr && real_lvalue_p (arg_expr))
11611 *arg = build_reference_type (*arg);
11613 /* [temp.deduct.call]
11615 If P is a cv-qualified type, the top level cv-qualifiers
11616 of P's type are ignored for type deduction. If P is a
11617 reference type, the type referred to by P is used for
11619 *parm = TYPE_MAIN_VARIANT (*parm);
11620 if (TREE_CODE (*parm) == REFERENCE_TYPE)
11622 *parm = TREE_TYPE (*parm);
11623 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
11626 /* DR 322. For conversion deduction, remove a reference type on parm
11627 too (which has been swapped into ARG). */
11628 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
11629 *arg = TREE_TYPE (*arg);
11634 /* Most parms like fn_type_unification.
11636 If SUBR is 1, we're being called recursively (to unify the
11637 arguments of a function or method parameter of a function
11641 type_unification_real (tree tparms,
11646 unification_kind_t strict,
11649 tree parm, arg, arg_expr;
11651 int ntparms = TREE_VEC_LENGTH (tparms);
11653 int saw_undeduced = 0;
11656 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
11657 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
11658 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
11659 gcc_assert (ntparms > 0);
11664 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
11665 | UNIFY_ALLOW_DERIVED);
11669 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
11673 sub_strict = UNIFY_ALLOW_NONE;
11677 gcc_unreachable ();
11684 while (parms && parms != void_list_node
11685 && args && args != void_list_node)
11687 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
11690 parm = TREE_VALUE (parms);
11691 parms = TREE_CHAIN (parms);
11692 arg = TREE_VALUE (args);
11693 args = TREE_CHAIN (args);
11696 if (arg == error_mark_node)
11698 if (arg == unknown_type_node)
11699 /* We can't deduce anything from this, but we might get all the
11700 template args from other function args. */
11703 /* Conversions will be performed on a function argument that
11704 corresponds with a function parameter that contains only
11705 non-deducible template parameters and explicitly specified
11706 template parameters. */
11707 if (!uses_template_parms (parm))
11712 type = TREE_TYPE (arg);
11716 if (same_type_p (parm, type))
11718 if (strict != DEDUCE_EXACT
11719 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
11728 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
11729 if (type_unknown_p (arg))
11731 /* [temp.deduct.type]
11733 A template-argument can be deduced from a pointer to
11734 function or pointer to member function argument if
11735 the set of overloaded functions does not contain
11736 function templates and at most one of a set of
11737 overloaded functions provides a unique match. */
11738 if (resolve_overloaded_unification
11739 (tparms, targs, parm, arg, strict, sub_strict))
11745 arg = unlowered_expr_type (arg);
11746 if (arg == error_mark_node)
11751 int arg_strict = sub_strict;
11754 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
11757 if (unify (tparms, targs, parm, arg, arg_strict))
11764 && parms != void_list_node
11765 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
11767 /* Unify the remaining arguments with the pack expansion type. */
11769 tree parmvec = make_tree_vec (1);
11773 /* Count the number of arguments that remain. */
11774 for (t = args; t && t != void_list_node; t = TREE_CHAIN (t))
11777 /* Allocate a TREE_VEC and copy in all of the arguments */
11778 argvec = make_tree_vec (len);
11779 for (i = 0; args && args != void_list_node; args = TREE_CHAIN (args))
11781 TREE_VEC_ELT (argvec, i) = TREE_VALUE (args);
11785 /* Copy the parameter into parmvec. */
11786 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
11787 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
11788 /*call_args_p=*/true, /*subr=*/subr))
11791 /* Advance to the end of the list of parameters. */
11792 parms = TREE_CHAIN (parms);
11795 /* Fail if we've reached the end of the parm list, and more args
11796 are present, and the parm list isn't variadic. */
11797 if (args && args != void_list_node && parms == void_list_node)
11799 /* Fail if parms are left and they don't have default values. */
11800 if (parms && parms != void_list_node
11801 && TREE_PURPOSE (parms) == NULL_TREE)
11805 for (i = 0; i < ntparms; i++)
11806 if (!TREE_VEC_ELT (targs, i))
11810 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
11813 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
11815 /* If this is an undeduced nontype parameter that depends on
11816 a type parameter, try another pass; its type may have been
11817 deduced from a later argument than the one from which
11818 this parameter can be deduced. */
11819 if (TREE_CODE (tparm) == PARM_DECL
11820 && uses_template_parms (TREE_TYPE (tparm))
11821 && !saw_undeduced++)
11824 /* Core issue #226 (C++0x) [temp.deduct]:
11826 If a template argument has not been deduced, its
11827 default template argument, if any, is used.
11829 When we are in C++98 mode, TREE_PURPOSE will either
11830 be NULL_TREE or ERROR_MARK_NODE, so we do not need
11831 to explicitly check cxx_dialect here. */
11832 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
11834 tree arg = tsubst (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)),
11835 targs, tf_none, NULL_TREE);
11836 if (arg == error_mark_node)
11840 TREE_VEC_ELT (targs, i) = arg;
11845 /* If the type parameter is a parameter pack, then it will
11846 be deduced to an empty parameter pack. */
11847 if (template_parameter_pack_p (tparm))
11851 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
11853 arg = make_node (NONTYPE_ARGUMENT_PACK);
11854 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
11855 TREE_CONSTANT (arg) = 1;
11858 arg = make_node (TYPE_ARGUMENT_PACK);
11860 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
11862 TREE_VEC_ELT (targs, i) = arg;
11872 /* Subroutine of type_unification_real. Args are like the variables
11873 at the call site. ARG is an overloaded function (or template-id);
11874 we try deducing template args from each of the overloads, and if
11875 only one succeeds, we go with that. Modifies TARGS and returns
11876 true on success. */
11879 resolve_overloaded_unification (tree tparms,
11883 unification_kind_t strict,
11886 tree tempargs = copy_node (targs);
11890 if (TREE_CODE (arg) == ADDR_EXPR)
11892 arg = TREE_OPERAND (arg, 0);
11898 if (TREE_CODE (arg) == COMPONENT_REF)
11899 /* Handle `&x' where `x' is some static or non-static member
11901 arg = TREE_OPERAND (arg, 1);
11903 if (TREE_CODE (arg) == OFFSET_REF)
11904 arg = TREE_OPERAND (arg, 1);
11906 /* Strip baselink information. */
11907 if (BASELINK_P (arg))
11908 arg = BASELINK_FUNCTIONS (arg);
11910 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
11912 /* If we got some explicit template args, we need to plug them into
11913 the affected templates before we try to unify, in case the
11914 explicit args will completely resolve the templates in question. */
11916 tree expl_subargs = TREE_OPERAND (arg, 1);
11917 arg = TREE_OPERAND (arg, 0);
11919 for (; arg; arg = OVL_NEXT (arg))
11921 tree fn = OVL_CURRENT (arg);
11922 tree subargs, elem;
11924 if (TREE_CODE (fn) != TEMPLATE_DECL)
11927 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
11928 expl_subargs, /*check_ret=*/false);
11931 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
11932 good += try_one_overload (tparms, targs, tempargs, parm,
11933 elem, strict, sub_strict, addr_p);
11937 else if (TREE_CODE (arg) != OVERLOAD
11938 && TREE_CODE (arg) != FUNCTION_DECL)
11939 /* If ARG is, for example, "(0, &f)" then its type will be unknown
11940 -- but the deduction does not succeed because the expression is
11941 not just the function on its own. */
11944 for (; arg; arg = OVL_NEXT (arg))
11945 good += try_one_overload (tparms, targs, tempargs, parm,
11946 TREE_TYPE (OVL_CURRENT (arg)),
11947 strict, sub_strict, addr_p);
11949 /* [temp.deduct.type] A template-argument can be deduced from a pointer
11950 to function or pointer to member function argument if the set of
11951 overloaded functions does not contain function templates and at most
11952 one of a set of overloaded functions provides a unique match.
11954 So if we found multiple possibilities, we return success but don't
11955 deduce anything. */
11959 int i = TREE_VEC_LENGTH (targs);
11961 if (TREE_VEC_ELT (tempargs, i))
11962 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
11970 /* Subroutine of resolve_overloaded_unification; does deduction for a single
11971 overload. Fills TARGS with any deduced arguments, or error_mark_node if
11972 different overloads deduce different arguments for a given parm.
11973 ADDR_P is true if the expression for which deduction is being
11974 performed was of the form "& fn" rather than simply "fn".
11976 Returns 1 on success. */
11979 try_one_overload (tree tparms,
11984 unification_kind_t strict,
11992 /* [temp.deduct.type] A template-argument can be deduced from a pointer
11993 to function or pointer to member function argument if the set of
11994 overloaded functions does not contain function templates and at most
11995 one of a set of overloaded functions provides a unique match.
11997 So if this is a template, just return success. */
11999 if (uses_template_parms (arg))
12002 if (TREE_CODE (arg) == METHOD_TYPE)
12003 arg = build_ptrmemfunc_type (build_pointer_type (arg));
12005 arg = build_pointer_type (arg);
12007 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
12009 /* We don't copy orig_targs for this because if we have already deduced
12010 some template args from previous args, unify would complain when we
12011 try to deduce a template parameter for the same argument, even though
12012 there isn't really a conflict. */
12013 nargs = TREE_VEC_LENGTH (targs);
12014 tempargs = make_tree_vec (nargs);
12016 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
12019 /* First make sure we didn't deduce anything that conflicts with
12020 explicitly specified args. */
12021 for (i = nargs; i--; )
12023 tree elt = TREE_VEC_ELT (tempargs, i);
12024 tree oldelt = TREE_VEC_ELT (orig_targs, i);
12028 else if (uses_template_parms (elt))
12029 /* Since we're unifying against ourselves, we will fill in
12030 template args used in the function parm list with our own
12031 template parms. Discard them. */
12032 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
12033 else if (oldelt && !template_args_equal (oldelt, elt))
12037 for (i = nargs; i--; )
12039 tree elt = TREE_VEC_ELT (tempargs, i);
12042 TREE_VEC_ELT (targs, i) = elt;
12048 /* PARM is a template class (perhaps with unbound template
12049 parameters). ARG is a fully instantiated type. If ARG can be
12050 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
12051 TARGS are as for unify. */
12054 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
12056 tree copy_of_targs;
12058 if (!CLASSTYPE_TEMPLATE_INFO (arg)
12059 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
12060 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
12063 /* We need to make a new template argument vector for the call to
12064 unify. If we used TARGS, we'd clutter it up with the result of
12065 the attempted unification, even if this class didn't work out.
12066 We also don't want to commit ourselves to all the unifications
12067 we've already done, since unification is supposed to be done on
12068 an argument-by-argument basis. In other words, consider the
12069 following pathological case:
12071 template <int I, int J, int K>
12074 template <int I, int J>
12075 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
12077 template <int I, int J, int K>
12078 void f(S<I, J, K>, S<I, I, I>);
12087 Now, by the time we consider the unification involving `s2', we
12088 already know that we must have `f<0, 0, 0>'. But, even though
12089 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
12090 because there are two ways to unify base classes of S<0, 1, 2>
12091 with S<I, I, I>. If we kept the already deduced knowledge, we
12092 would reject the possibility I=1. */
12093 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
12095 /* If unification failed, we're done. */
12096 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
12097 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
12103 /* Given a template type PARM and a class type ARG, find the unique
12104 base type in ARG that is an instance of PARM. We do not examine
12105 ARG itself; only its base-classes. If there is not exactly one
12106 appropriate base class, return NULL_TREE. PARM may be the type of
12107 a partial specialization, as well as a plain template type. Used
12111 get_template_base (tree tparms, tree targs, tree parm, tree arg)
12113 tree rval = NULL_TREE;
12116 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
12118 binfo = TYPE_BINFO (complete_type (arg));
12120 /* The type could not be completed. */
12123 /* Walk in inheritance graph order. The search order is not
12124 important, and this avoids multiple walks of virtual bases. */
12125 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
12127 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
12131 /* If there is more than one satisfactory baseclass, then:
12135 If they yield more than one possible deduced A, the type
12139 if (rval && !same_type_p (r, rval))
12149 /* Returns the level of DECL, which declares a template parameter. */
12152 template_decl_level (tree decl)
12154 switch (TREE_CODE (decl))
12157 case TEMPLATE_DECL:
12158 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
12161 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
12164 gcc_unreachable ();
12169 /* Decide whether ARG can be unified with PARM, considering only the
12170 cv-qualifiers of each type, given STRICT as documented for unify.
12171 Returns nonzero iff the unification is OK on that basis. */
12174 check_cv_quals_for_unify (int strict, tree arg, tree parm)
12176 int arg_quals = cp_type_quals (arg);
12177 int parm_quals = cp_type_quals (parm);
12179 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
12180 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
12182 /* Although a CVR qualifier is ignored when being applied to a
12183 substituted template parameter ([8.3.2]/1 for example), that
12184 does not apply during deduction [14.8.2.4]/1, (even though
12185 that is not explicitly mentioned, [14.8.2.4]/9 indicates
12186 this). Except when we're allowing additional CV qualifiers
12187 at the outer level [14.8.2.1]/3,1st bullet. */
12188 if ((TREE_CODE (arg) == REFERENCE_TYPE
12189 || TREE_CODE (arg) == FUNCTION_TYPE
12190 || TREE_CODE (arg) == METHOD_TYPE)
12191 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
12194 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
12195 && (parm_quals & TYPE_QUAL_RESTRICT))
12199 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
12200 && (arg_quals & parm_quals) != parm_quals)
12203 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
12204 && (parm_quals & arg_quals) != arg_quals)
12210 /* Determines the LEVEL and INDEX for the template parameter PARM. */
12212 template_parm_level_and_index (tree parm, int* level, int* index)
12214 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
12215 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
12216 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
12218 *index = TEMPLATE_TYPE_IDX (parm);
12219 *level = TEMPLATE_TYPE_LEVEL (parm);
12223 *index = TEMPLATE_PARM_IDX (parm);
12224 *level = TEMPLATE_PARM_LEVEL (parm);
12228 /* Unifies the remaining arguments in PACKED_ARGS with the pack
12229 expansion at the end of PACKED_PARMS. Returns 0 if the type
12230 deduction succeeds, 1 otherwise. STRICT is the same as in
12231 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
12232 call argument list. We'll need to adjust the arguments to make them
12233 types. SUBR tells us if this is from a recursive call to
12234 type_unification_real. */
12236 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
12237 tree packed_args, int strict, bool call_args_p,
12241 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
12242 tree pattern = PACK_EXPANSION_PATTERN (parm);
12243 tree pack, packs = NULL_TREE;
12244 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
12245 int len = TREE_VEC_LENGTH (packed_args);
12247 /* Determine the parameter packs we will be deducing from the
12248 pattern, and record their current deductions. */
12249 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
12250 pack; pack = TREE_CHAIN (pack))
12252 tree parm_pack = TREE_VALUE (pack);
12255 /* Determine the index and level of this parameter pack. */
12256 template_parm_level_and_index (parm_pack, &level, &idx);
12258 /* Keep track of the parameter packs and their corresponding
12260 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
12261 TREE_TYPE (packs) = make_tree_vec (len - start);
12264 /* Loop through all of the arguments that have not yet been
12265 unified and unify each with the pattern. */
12266 for (i = start; i < len; i++)
12268 tree parm = pattern;
12270 /* For each parameter pack, clear out the deduced value so that
12271 we can deduce it again. */
12272 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12275 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12277 TMPL_ARG (targs, level, idx) = NULL_TREE;
12280 /* Unify the pattern with the current argument. */
12282 tree arg = TREE_VEC_ELT (packed_args, i);
12283 int arg_strict = strict;
12284 bool skip_arg_p = false;
12290 /* This mirrors what we do in type_unification_real. */
12294 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
12295 | UNIFY_ALLOW_MORE_CV_QUAL
12296 | UNIFY_ALLOW_DERIVED);
12300 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
12304 sub_strict = UNIFY_ALLOW_NONE;
12308 gcc_unreachable ();
12313 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
12314 if (type_unknown_p (arg))
12316 /* [temp.deduct.type] A template-argument can be
12317 deduced from a pointer to function or pointer
12318 to member function argument if the set of
12319 overloaded functions does not contain function
12320 templates and at most one of a set of
12321 overloaded functions provides a unique
12324 if (resolve_overloaded_unification
12325 (tparms, targs, parm, arg, strict, sub_strict)
12333 arg = TREE_TYPE (arg);
12334 if (arg == error_mark_node)
12339 arg_strict = sub_strict;
12343 maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
12348 if (unify (tparms, targs, parm, arg, arg_strict))
12353 /* For each parameter pack, collect the deduced value. */
12354 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12357 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12359 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
12360 TMPL_ARG (targs, level, idx);
12364 /* Verify that the results of unification with the parameter packs
12365 produce results consistent with what we've seen before, and make
12366 the deduced argument packs available. */
12367 for (pack = packs; pack; pack = TREE_CHAIN (pack))
12369 tree old_pack = TREE_VALUE (pack);
12370 tree new_args = TREE_TYPE (pack);
12372 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
12374 /* Prepend the explicit arguments onto NEW_ARGS. */
12375 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
12376 tree old_args = new_args;
12377 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
12378 int len = explicit_len + TREE_VEC_LENGTH (old_args);
12380 /* Copy the explicit arguments. */
12381 new_args = make_tree_vec (len);
12382 for (i = 0; i < explicit_len; i++)
12383 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
12385 /* Copy the deduced arguments. */
12386 for (; i < len; i++)
12387 TREE_VEC_ELT (new_args, i) =
12388 TREE_VEC_ELT (old_args, i - explicit_len);
12396 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12398 /* Build the deduced *_ARGUMENT_PACK. */
12399 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
12401 result = make_node (NONTYPE_ARGUMENT_PACK);
12402 TREE_TYPE (result) =
12403 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
12404 TREE_CONSTANT (result) = 1;
12407 result = make_node (TYPE_ARGUMENT_PACK);
12409 SET_ARGUMENT_PACK_ARGS (result, new_args);
12411 /* Note the deduced argument packs for this parameter
12413 TMPL_ARG (targs, level, idx) = result;
12415 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
12416 && (ARGUMENT_PACK_ARGS (old_pack)
12417 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
12419 /* We only had the explicitly-provided arguments before, but
12420 now we have a complete set of arguments. */
12422 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
12423 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12425 /* Keep the original deduced argument pack. */
12426 TMPL_ARG (targs, level, idx) = old_pack;
12428 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
12429 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
12430 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
12432 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
12434 /* Inconsistent unification of this parameter pack. */
12440 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
12442 /* Keep the original deduced argument pack. */
12443 TMPL_ARG (targs, level, idx) = old_pack;
12450 /* Deduce the value of template parameters. TPARMS is the (innermost)
12451 set of template parameters to a template. TARGS is the bindings
12452 for those template parameters, as determined thus far; TARGS may
12453 include template arguments for outer levels of template parameters
12454 as well. PARM is a parameter to a template function, or a
12455 subcomponent of that parameter; ARG is the corresponding argument.
12456 This function attempts to match PARM with ARG in a manner
12457 consistent with the existing assignments in TARGS. If more values
12458 are deduced, then TARGS is updated.
12460 Returns 0 if the type deduction succeeds, 1 otherwise. The
12461 parameter STRICT is a bitwise or of the following flags:
12464 Require an exact match between PARM and ARG.
12465 UNIFY_ALLOW_MORE_CV_QUAL:
12466 Allow the deduced ARG to be more cv-qualified (by qualification
12467 conversion) than ARG.
12468 UNIFY_ALLOW_LESS_CV_QUAL:
12469 Allow the deduced ARG to be less cv-qualified than ARG.
12470 UNIFY_ALLOW_DERIVED:
12471 Allow the deduced ARG to be a template base class of ARG,
12472 or a pointer to a template base class of the type pointed to by
12474 UNIFY_ALLOW_INTEGER:
12475 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
12476 case for more information.
12477 UNIFY_ALLOW_OUTER_LEVEL:
12478 This is the outermost level of a deduction. Used to determine validity
12479 of qualification conversions. A valid qualification conversion must
12480 have const qualified pointers leading up to the inner type which
12481 requires additional CV quals, except at the outer level, where const
12482 is not required [conv.qual]. It would be normal to set this flag in
12483 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
12484 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
12485 This is the outermost level of a deduction, and PARM can be more CV
12486 qualified at this point.
12487 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
12488 This is the outermost level of a deduction, and PARM can be less CV
12489 qualified at this point. */
12492 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
12497 int strict_in = strict;
12499 /* I don't think this will do the right thing with respect to types.
12500 But the only case I've seen it in so far has been array bounds, where
12501 signedness is the only information lost, and I think that will be
12503 while (TREE_CODE (parm) == NOP_EXPR)
12504 parm = TREE_OPERAND (parm, 0);
12506 if (arg == error_mark_node)
12508 if (arg == unknown_type_node)
12509 /* We can't deduce anything from this, but we might get all the
12510 template args from other function args. */
12513 /* If PARM uses template parameters, then we can't bail out here,
12514 even if ARG == PARM, since we won't record unifications for the
12515 template parameters. We might need them if we're trying to
12516 figure out which of two things is more specialized. */
12517 if (arg == parm && !uses_template_parms (parm))
12520 /* Immediately reject some pairs that won't unify because of
12521 cv-qualification mismatches. */
12522 if (TREE_CODE (arg) == TREE_CODE (parm)
12524 /* It is the elements of the array which hold the cv quals of an array
12525 type, and the elements might be template type parms. We'll check
12526 when we recurse. */
12527 && TREE_CODE (arg) != ARRAY_TYPE
12528 /* We check the cv-qualifiers when unifying with template type
12529 parameters below. We want to allow ARG `const T' to unify with
12530 PARM `T' for example, when computing which of two templates
12531 is more specialized, for example. */
12532 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
12533 && !check_cv_quals_for_unify (strict_in, arg, parm))
12536 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
12537 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
12538 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
12539 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
12540 strict &= ~UNIFY_ALLOW_DERIVED;
12541 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
12542 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
12544 switch (TREE_CODE (parm))
12546 case TYPENAME_TYPE:
12548 case UNBOUND_CLASS_TEMPLATE:
12549 /* In a type which contains a nested-name-specifier, template
12550 argument values cannot be deduced for template parameters used
12551 within the nested-name-specifier. */
12554 case TEMPLATE_TYPE_PARM:
12555 case TEMPLATE_TEMPLATE_PARM:
12556 case BOUND_TEMPLATE_TEMPLATE_PARM:
12557 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
12558 if (tparm == error_mark_node)
12561 if (TEMPLATE_TYPE_LEVEL (parm)
12562 != template_decl_level (tparm))
12563 /* The PARM is not one we're trying to unify. Just check
12564 to see if it matches ARG. */
12565 return (TREE_CODE (arg) == TREE_CODE (parm)
12566 && same_type_p (parm, arg)) ? 0 : 1;
12567 idx = TEMPLATE_TYPE_IDX (parm);
12568 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
12569 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
12571 /* Check for mixed types and values. */
12572 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
12573 && TREE_CODE (tparm) != TYPE_DECL)
12574 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
12575 && TREE_CODE (tparm) != TEMPLATE_DECL))
12578 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
12580 /* ARG must be constructed from a template class or a template
12581 template parameter. */
12582 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
12583 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
12587 tree parmvec = TYPE_TI_ARGS (parm);
12588 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
12590 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
12593 /* The resolution to DR150 makes clear that default
12594 arguments for an N-argument may not be used to bind T
12595 to a template template parameter with fewer than N
12596 parameters. It is not safe to permit the binding of
12597 default arguments as an extension, as that may change
12598 the meaning of a conforming program. Consider:
12600 struct Dense { static const unsigned int dim = 1; };
12602 template <template <typename> class View,
12604 void operator+(float, View<Block> const&);
12606 template <typename Block,
12607 unsigned int Dim = Block::dim>
12608 struct Lvalue_proxy { operator float() const; };
12612 Lvalue_proxy<Dense> p;
12617 Here, if Lvalue_proxy is permitted to bind to View, then
12618 the global operator+ will be used; if they are not, the
12619 Lvalue_proxy will be converted to float. */
12620 if (coerce_template_parms (argtmplvec, parmvec,
12621 TYPE_TI_TEMPLATE (parm),
12623 /*require_all_args=*/true,
12624 /*use_default_args=*/false)
12625 == error_mark_node)
12628 /* Deduce arguments T, i from TT<T> or TT<i>.
12629 We check each element of PARMVEC and ARGVEC individually
12630 rather than the whole TREE_VEC since they can have
12631 different number of elements. */
12633 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
12635 if (unify (tparms, targs,
12636 TREE_VEC_ELT (parmvec, i),
12637 TREE_VEC_ELT (argvec, i),
12642 arg = TYPE_TI_TEMPLATE (arg);
12644 /* Fall through to deduce template name. */
12647 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
12648 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
12650 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
12652 /* Simple cases: Value already set, does match or doesn't. */
12653 if (targ != NULL_TREE && template_args_equal (targ, arg))
12660 /* If PARM is `const T' and ARG is only `int', we don't have
12661 a match unless we are allowing additional qualification.
12662 If ARG is `const int' and PARM is just `T' that's OK;
12663 that binds `const int' to `T'. */
12664 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
12668 /* Consider the case where ARG is `const volatile int' and
12669 PARM is `const T'. Then, T should be `volatile int'. */
12670 arg = cp_build_qualified_type_real
12671 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
12672 if (arg == error_mark_node)
12675 /* Simple cases: Value already set, does match or doesn't. */
12676 if (targ != NULL_TREE && same_type_p (targ, arg))
12681 /* Make sure that ARG is not a variable-sized array. (Note
12682 that were talking about variable-sized arrays (like
12683 `int[n]'), rather than arrays of unknown size (like
12684 `int[]').) We'll get very confused by such a type since
12685 the bound of the array will not be computable in an
12686 instantiation. Besides, such types are not allowed in
12687 ISO C++, so we can do as we please here. */
12688 if (variably_modified_type_p (arg, NULL_TREE))
12692 /* If ARG is a parameter pack or an expansion, we cannot unify
12693 against it unless PARM is also a parameter pack. */
12694 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
12695 && !template_parameter_pack_p (parm))
12698 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
12701 case TEMPLATE_PARM_INDEX:
12702 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
12703 if (tparm == error_mark_node)
12706 if (TEMPLATE_PARM_LEVEL (parm)
12707 != template_decl_level (tparm))
12708 /* The PARM is not one we're trying to unify. Just check
12709 to see if it matches ARG. */
12710 return !(TREE_CODE (arg) == TREE_CODE (parm)
12711 && cp_tree_equal (parm, arg));
12713 idx = TEMPLATE_PARM_IDX (parm);
12714 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
12717 return !cp_tree_equal (targ, arg);
12719 /* [temp.deduct.type] If, in the declaration of a function template
12720 with a non-type template-parameter, the non-type
12721 template-parameter is used in an expression in the function
12722 parameter-list and, if the corresponding template-argument is
12723 deduced, the template-argument type shall match the type of the
12724 template-parameter exactly, except that a template-argument
12725 deduced from an array bound may be of any integral type.
12726 The non-type parameter might use already deduced type parameters. */
12727 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
12728 if (!TREE_TYPE (arg))
12729 /* Template-parameter dependent expression. Just accept it for now.
12730 It will later be processed in convert_template_argument. */
12732 else if (same_type_p (TREE_TYPE (arg), tparm))
12734 else if ((strict & UNIFY_ALLOW_INTEGER)
12735 && (TREE_CODE (tparm) == INTEGER_TYPE
12736 || TREE_CODE (tparm) == BOOLEAN_TYPE))
12737 /* Convert the ARG to the type of PARM; the deduced non-type
12738 template argument must exactly match the types of the
12739 corresponding parameter. */
12740 arg = fold (build_nop (TREE_TYPE (parm), arg));
12741 else if (uses_template_parms (tparm))
12742 /* We haven't deduced the type of this parameter yet. Try again
12748 /* If ARG is a parameter pack or an expansion, we cannot unify
12749 against it unless PARM is also a parameter pack. */
12750 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
12751 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
12754 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
12759 /* A pointer-to-member constant can be unified only with
12760 another constant. */
12761 if (TREE_CODE (arg) != PTRMEM_CST)
12764 /* Just unify the class member. It would be useless (and possibly
12765 wrong, depending on the strict flags) to unify also
12766 PTRMEM_CST_CLASS, because we want to be sure that both parm and
12767 arg refer to the same variable, even if through different
12768 classes. For instance:
12770 struct A { int x; };
12773 Unification of &A::x and &B::x must succeed. */
12774 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
12775 PTRMEM_CST_MEMBER (arg), strict);
12780 if (TREE_CODE (arg) != POINTER_TYPE)
12783 /* [temp.deduct.call]
12785 A can be another pointer or pointer to member type that can
12786 be converted to the deduced A via a qualification
12787 conversion (_conv.qual_).
12789 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
12790 This will allow for additional cv-qualification of the
12791 pointed-to types if appropriate. */
12793 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
12794 /* The derived-to-base conversion only persists through one
12795 level of pointers. */
12796 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
12798 return unify (tparms, targs, TREE_TYPE (parm),
12799 TREE_TYPE (arg), strict);
12802 case REFERENCE_TYPE:
12803 if (TREE_CODE (arg) != REFERENCE_TYPE)
12805 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
12806 strict & UNIFY_ALLOW_MORE_CV_QUAL);
12809 if (TREE_CODE (arg) != ARRAY_TYPE)
12811 if ((TYPE_DOMAIN (parm) == NULL_TREE)
12812 != (TYPE_DOMAIN (arg) == NULL_TREE))
12814 if (TYPE_DOMAIN (parm) != NULL_TREE)
12821 /* Our representation of array types uses "N - 1" as the
12822 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
12823 not an integer constant. We cannot unify arbitrarily
12824 complex expressions, so we eliminate the MINUS_EXPRs
12826 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
12827 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
12830 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
12831 parm_max = TREE_OPERAND (parm_max, 0);
12833 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
12834 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
12837 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
12838 trying to unify the type of a variable with the type
12839 of a template parameter. For example:
12841 template <unsigned int N>
12842 void f (char (&) [N]);
12849 Here, the type of the ARG will be "int [g(i)]", and
12850 may be a SAVE_EXPR, etc. */
12851 if (TREE_CODE (arg_max) != MINUS_EXPR)
12853 arg_max = TREE_OPERAND (arg_max, 0);
12856 /* If only one of the bounds used a MINUS_EXPR, compensate
12857 by adding one to the other bound. */
12858 if (parm_cst && !arg_cst)
12859 parm_max = fold_build2 (PLUS_EXPR,
12863 else if (arg_cst && !parm_cst)
12864 arg_max = fold_build2 (PLUS_EXPR,
12869 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
12872 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
12873 strict & UNIFY_ALLOW_MORE_CV_QUAL);
12880 case ENUMERAL_TYPE:
12882 if (TREE_CODE (arg) != TREE_CODE (parm))
12885 /* We have already checked cv-qualification at the top of the
12887 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
12890 /* As far as unification is concerned, this wins. Later checks
12891 will invalidate it if necessary. */
12894 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
12895 /* Type INTEGER_CST can come from ordinary constant template args. */
12897 while (TREE_CODE (arg) == NOP_EXPR)
12898 arg = TREE_OPERAND (arg, 0);
12900 if (TREE_CODE (arg) != INTEGER_CST)
12902 return !tree_int_cst_equal (parm, arg);
12907 if (TREE_CODE (arg) != TREE_VEC)
12909 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
12911 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
12912 if (unify (tparms, targs,
12913 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
12921 if (TREE_CODE (arg) != TREE_CODE (parm))
12924 if (TYPE_PTRMEMFUNC_P (parm))
12926 if (!TYPE_PTRMEMFUNC_P (arg))
12929 return unify (tparms, targs,
12930 TYPE_PTRMEMFUNC_FN_TYPE (parm),
12931 TYPE_PTRMEMFUNC_FN_TYPE (arg),
12935 if (CLASSTYPE_TEMPLATE_INFO (parm))
12937 tree t = NULL_TREE;
12939 if (strict_in & UNIFY_ALLOW_DERIVED)
12941 /* First, we try to unify the PARM and ARG directly. */
12942 t = try_class_unification (tparms, targs,
12947 /* Fallback to the special case allowed in
12948 [temp.deduct.call]:
12950 If P is a class, and P has the form
12951 template-id, then A can be a derived class of
12952 the deduced A. Likewise, if P is a pointer to
12953 a class of the form template-id, A can be a
12954 pointer to a derived class pointed to by the
12956 t = get_template_base (tparms, targs, parm, arg);
12962 else if (CLASSTYPE_TEMPLATE_INFO (arg)
12963 && (CLASSTYPE_TI_TEMPLATE (parm)
12964 == CLASSTYPE_TI_TEMPLATE (arg)))
12965 /* Perhaps PARM is something like S<U> and ARG is S<int>.
12966 Then, we should unify `int' and `U'. */
12969 /* There's no chance of unification succeeding. */
12972 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
12973 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
12975 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
12980 case FUNCTION_TYPE:
12981 if (TREE_CODE (arg) != TREE_CODE (parm))
12984 /* CV qualifications for methods can never be deduced, they must
12985 match exactly. We need to check them explicitly here,
12986 because type_unification_real treats them as any other
12987 cvqualified parameter. */
12988 if (TREE_CODE (parm) == METHOD_TYPE
12989 && (!check_cv_quals_for_unify
12991 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
12992 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
12995 if (unify (tparms, targs, TREE_TYPE (parm),
12996 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
12998 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
12999 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
13003 /* Unify a pointer to member with a pointer to member function, which
13004 deduces the type of the member as a function type. */
13005 if (TYPE_PTRMEMFUNC_P (arg))
13009 cp_cv_quals cv_quals;
13011 /* Check top-level cv qualifiers */
13012 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
13015 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
13016 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
13019 /* Determine the type of the function we are unifying against. */
13020 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
13022 build_function_type (TREE_TYPE (method_type),
13023 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
13025 /* Extract the cv-qualifiers of the member function from the
13026 implicit object parameter and place them on the function
13027 type to be restored later. */
13029 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
13030 fntype = build_qualified_type (fntype, cv_quals);
13031 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
13034 if (TREE_CODE (arg) != OFFSET_TYPE)
13036 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
13037 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
13039 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
13043 if (DECL_TEMPLATE_PARM_P (parm))
13044 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
13045 if (arg != integral_constant_value (parm))
13050 case TEMPLATE_DECL:
13051 /* Matched cases are handled by the ARG == PARM test above. */
13054 case TYPE_ARGUMENT_PACK:
13055 case NONTYPE_ARGUMENT_PACK:
13057 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
13058 tree packed_args = ARGUMENT_PACK_ARGS (arg);
13059 int i, len = TREE_VEC_LENGTH (packed_parms);
13060 int argslen = TREE_VEC_LENGTH (packed_args);
13061 int parm_variadic_p = 0;
13063 /* Check if the parameters end in a pack, making them variadic. */
13065 && PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, len - 1)))
13066 parm_variadic_p = 1;
13068 /* If we don't have enough arguments to satisfy the parameters
13069 (not counting the pack expression at the end), or we have
13070 too many arguments for a parameter list that doesn't end in
13071 a pack expression, we can't unify. */
13072 if (argslen < (len - parm_variadic_p)
13073 || (argslen > len && !parm_variadic_p))
13076 /* Unify all of the parameters that precede the (optional)
13077 pack expression. */
13078 for (i = 0; i < len - parm_variadic_p; ++i)
13080 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
13081 TREE_VEC_ELT (packed_args, i), strict))
13085 if (parm_variadic_p)
13086 return unify_pack_expansion (tparms, targs,
13087 packed_parms, packed_args,
13088 strict, /*call_args_p=*/false,
13096 case DECLTYPE_TYPE:
13097 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
13102 gcc_assert (EXPR_P (parm));
13104 /* We must be looking at an expression. This can happen with
13108 void foo(S<I>, S<I + 2>);
13110 This is a "nondeduced context":
13114 The nondeduced contexts are:
13116 --A type that is a template-id in which one or more of
13117 the template-arguments is an expression that references
13118 a template-parameter.
13120 In these cases, we assume deduction succeeded, but don't
13121 actually infer any unifications. */
13123 if (!uses_template_parms (parm)
13124 && !template_args_equal (parm, arg))
13131 /* Note that DECL can be defined in this translation unit, if
13135 mark_definable (tree decl)
13138 DECL_NOT_REALLY_EXTERN (decl) = 1;
13139 FOR_EACH_CLONE (clone, decl)
13140 DECL_NOT_REALLY_EXTERN (clone) = 1;
13143 /* Called if RESULT is explicitly instantiated, or is a member of an
13144 explicitly instantiated class. */
13147 mark_decl_instantiated (tree result, int extern_p)
13149 SET_DECL_EXPLICIT_INSTANTIATION (result);
13151 /* If this entity has already been written out, it's too late to
13152 make any modifications. */
13153 if (TREE_ASM_WRITTEN (result))
13156 if (TREE_CODE (result) != FUNCTION_DECL)
13157 /* The TREE_PUBLIC flag for function declarations will have been
13158 set correctly by tsubst. */
13159 TREE_PUBLIC (result) = 1;
13161 /* This might have been set by an earlier implicit instantiation. */
13162 DECL_COMDAT (result) = 0;
13165 DECL_NOT_REALLY_EXTERN (result) = 0;
13168 mark_definable (result);
13169 /* Always make artificials weak. */
13170 if (DECL_ARTIFICIAL (result) && flag_weak)
13171 comdat_linkage (result);
13172 /* For WIN32 we also want to put explicit instantiations in
13173 linkonce sections. */
13174 else if (TREE_PUBLIC (result))
13175 maybe_make_one_only (result);
13178 /* If EXTERN_P, then this function will not be emitted -- unless
13179 followed by an explicit instantiation, at which point its linkage
13180 will be adjusted. If !EXTERN_P, then this function will be
13181 emitted here. In neither circumstance do we want
13182 import_export_decl to adjust the linkage. */
13183 DECL_INTERFACE_KNOWN (result) = 1;
13186 /* Given two function templates PAT1 and PAT2, return:
13188 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
13189 -1 if PAT2 is more specialized than PAT1.
13190 0 if neither is more specialized.
13192 LEN indicates the number of parameters we should consider
13193 (defaulted parameters should not be considered).
13195 The 1998 std underspecified function template partial ordering, and
13196 DR214 addresses the issue. We take pairs of arguments, one from
13197 each of the templates, and deduce them against each other. One of
13198 the templates will be more specialized if all the *other*
13199 template's arguments deduce against its arguments and at least one
13200 of its arguments *does* *not* deduce against the other template's
13201 corresponding argument. Deduction is done as for class templates.
13202 The arguments used in deduction have reference and top level cv
13203 qualifiers removed. Iff both arguments were originally reference
13204 types *and* deduction succeeds in both directions, the template
13205 with the more cv-qualified argument wins for that pairing (if
13206 neither is more cv-qualified, they both are equal). Unlike regular
13207 deduction, after all the arguments have been deduced in this way,
13208 we do *not* verify the deduced template argument values can be
13209 substituted into non-deduced contexts, nor do we have to verify
13210 that all template arguments have been deduced. */
13213 more_specialized_fn (tree pat1, tree pat2, int len)
13215 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
13216 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
13217 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
13218 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
13219 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
13220 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
13221 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
13222 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
13226 /* Remove the this parameter from non-static member functions. If
13227 one is a non-static member function and the other is not a static
13228 member function, remove the first parameter from that function
13229 also. This situation occurs for operator functions where we
13230 locate both a member function (with this pointer) and non-member
13231 operator (with explicit first operand). */
13232 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
13234 len--; /* LEN is the number of significant arguments for DECL1 */
13235 args1 = TREE_CHAIN (args1);
13236 if (!DECL_STATIC_FUNCTION_P (decl2))
13237 args2 = TREE_CHAIN (args2);
13239 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
13241 args2 = TREE_CHAIN (args2);
13242 if (!DECL_STATIC_FUNCTION_P (decl1))
13245 args1 = TREE_CHAIN (args1);
13249 /* If only one is a conversion operator, they are unordered. */
13250 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
13253 /* Consider the return type for a conversion function */
13254 if (DECL_CONV_FN_P (decl1))
13256 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
13257 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
13261 processing_template_decl++;
13265 tree arg1 = TREE_VALUE (args1);
13266 tree arg2 = TREE_VALUE (args2);
13267 int deduce1, deduce2;
13271 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
13272 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
13274 /* When both arguments are pack expansions, we need only
13275 unify the patterns themselves. */
13276 arg1 = PACK_EXPANSION_PATTERN (arg1);
13277 arg2 = PACK_EXPANSION_PATTERN (arg2);
13279 /* This is the last comparison we need to do. */
13283 if (TREE_CODE (arg1) == REFERENCE_TYPE)
13285 arg1 = TREE_TYPE (arg1);
13286 quals1 = cp_type_quals (arg1);
13289 if (TREE_CODE (arg2) == REFERENCE_TYPE)
13291 arg2 = TREE_TYPE (arg2);
13292 quals2 = cp_type_quals (arg2);
13295 if ((quals1 < 0) != (quals2 < 0))
13297 /* Only of the args is a reference, see if we should apply
13298 array/function pointer decay to it. This is not part of
13299 DR214, but is, IMHO, consistent with the deduction rules
13300 for the function call itself, and with our earlier
13301 implementation of the underspecified partial ordering
13302 rules. (nathan). */
13305 switch (TREE_CODE (arg1))
13308 arg1 = TREE_TYPE (arg1);
13310 case FUNCTION_TYPE:
13311 arg1 = build_pointer_type (arg1);
13320 switch (TREE_CODE (arg2))
13323 arg2 = TREE_TYPE (arg2);
13325 case FUNCTION_TYPE:
13326 arg2 = build_pointer_type (arg2);
13335 arg1 = TYPE_MAIN_VARIANT (arg1);
13336 arg2 = TYPE_MAIN_VARIANT (arg2);
13338 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
13340 int i, len2 = list_length (args2);
13341 tree parmvec = make_tree_vec (1);
13342 tree argvec = make_tree_vec (len2);
13345 /* Setup the parameter vector, which contains only ARG1. */
13346 TREE_VEC_ELT (parmvec, 0) = arg1;
13348 /* Setup the argument vector, which contains the remaining
13350 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
13351 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
13353 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
13354 argvec, UNIFY_ALLOW_NONE,
13355 /*call_args_p=*/false,
13358 /* We cannot deduce in the other direction, because ARG1 is
13359 a pack expansion but ARG2 is not. */
13362 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
13364 int i, len1 = list_length (args1);
13365 tree parmvec = make_tree_vec (1);
13366 tree argvec = make_tree_vec (len1);
13369 /* Setup the parameter vector, which contains only ARG1. */
13370 TREE_VEC_ELT (parmvec, 0) = arg2;
13372 /* Setup the argument vector, which contains the remaining
13374 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
13375 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
13377 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
13378 argvec, UNIFY_ALLOW_NONE,
13379 /*call_args_p=*/false,
13382 /* We cannot deduce in the other direction, because ARG2 is
13383 a pack expansion but ARG1 is not.*/
13389 /* The normal case, where neither argument is a pack
13391 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
13392 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
13399 if (better1 < 0 && better2 < 0)
13400 /* We've failed to deduce something in either direction.
13401 These must be unordered. */
13404 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
13406 /* Deduces in both directions, see if quals can
13407 disambiguate. Pretend the worse one failed to deduce. */
13408 if ((quals1 & quals2) == quals2)
13410 if ((quals1 & quals2) == quals1)
13413 if (deduce1 && !deduce2 && !better2)
13415 if (deduce2 && !deduce1 && !better1)
13418 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
13419 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
13420 /* We have already processed all of the arguments in our
13421 handing of the pack expansion type. */
13424 args1 = TREE_CHAIN (args1);
13425 args2 = TREE_CHAIN (args2);
13428 processing_template_decl--;
13430 /* All things being equal, if the next argument is a pack expansion
13431 for one function but not for the other, prefer the
13432 non-variadic function. */
13433 if ((better1 > 0) - (better2 > 0) == 0
13434 && args1 && TREE_VALUE (args1)
13435 && args2 && TREE_VALUE (args2))
13437 if (TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION)
13438 return TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION ? 0 : -1;
13439 else if (TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION)
13443 return (better1 > 0) - (better2 > 0);
13446 /* Determine which of two partial specializations is more specialized.
13448 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
13449 to the first partial specialization. The TREE_VALUE is the
13450 innermost set of template parameters for the partial
13451 specialization. PAT2 is similar, but for the second template.
13453 Return 1 if the first partial specialization is more specialized;
13454 -1 if the second is more specialized; 0 if neither is more
13457 See [temp.class.order] for information about determining which of
13458 two templates is more specialized. */
13461 more_specialized_class (tree pat1, tree pat2)
13466 bool any_deductions = false;
13468 tmpl1 = TREE_TYPE (pat1);
13469 tmpl2 = TREE_TYPE (pat2);
13471 /* Just like what happens for functions, if we are ordering between
13472 different class template specializations, we may encounter dependent
13473 types in the arguments, and we need our dependency check functions
13474 to behave correctly. */
13475 ++processing_template_decl;
13476 targs = get_class_bindings (TREE_VALUE (pat1),
13477 CLASSTYPE_TI_ARGS (tmpl1),
13478 CLASSTYPE_TI_ARGS (tmpl2));
13482 any_deductions = true;
13485 targs = get_class_bindings (TREE_VALUE (pat2),
13486 CLASSTYPE_TI_ARGS (tmpl2),
13487 CLASSTYPE_TI_ARGS (tmpl1));
13491 any_deductions = true;
13493 --processing_template_decl;
13495 /* In the case of a tie where at least one of the class templates
13496 has a parameter pack at the end, the template with the most
13497 non-packed parameters wins. */
13500 && (template_args_variadic_p (TREE_PURPOSE (pat1))
13501 || template_args_variadic_p (TREE_PURPOSE (pat2))))
13503 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
13504 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
13505 int len1 = TREE_VEC_LENGTH (args1);
13506 int len2 = TREE_VEC_LENGTH (args2);
13508 /* We don't count the pack expansion at the end. */
13509 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
13511 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
13516 else if (len1 < len2)
13523 /* Return the template arguments that will produce the function signature
13524 DECL from the function template FN, with the explicit template
13525 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
13526 also match. Return NULL_TREE if no satisfactory arguments could be
13530 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
13532 int ntparms = DECL_NTPARMS (fn);
13533 tree targs = make_tree_vec (ntparms);
13535 tree decl_arg_types;
13537 /* Substitute the explicit template arguments into the type of DECL.
13538 The call to fn_type_unification will handle substitution into the
13540 decl_type = TREE_TYPE (decl);
13541 if (explicit_args && uses_template_parms (decl_type))
13544 tree converted_args;
13546 if (DECL_TEMPLATE_INFO (decl))
13547 tmpl = DECL_TI_TEMPLATE (decl);
13549 /* We can get here for some invalid specializations. */
13553 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
13554 explicit_args, NULL_TREE,
13556 /*require_all_args=*/false,
13557 /*use_default_args=*/false);
13558 if (converted_args == error_mark_node)
13561 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
13562 if (decl_type == error_mark_node)
13566 /* Never do unification on the 'this' parameter. */
13567 decl_arg_types = skip_artificial_parms_for (decl,
13568 TYPE_ARG_TYPES (decl_type));
13570 if (fn_type_unification (fn, explicit_args, targs,
13572 (check_rettype || DECL_CONV_FN_P (fn)
13573 ? TREE_TYPE (decl_type) : NULL_TREE),
13574 DEDUCE_EXACT, LOOKUP_NORMAL))
13580 /* Return the innermost template arguments that, when applied to a
13581 template specialization whose innermost template parameters are
13582 TPARMS, and whose specialization arguments are PARMS, yield the
13585 For example, suppose we have:
13587 template <class T, class U> struct S {};
13588 template <class T> struct S<T*, int> {};
13590 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
13591 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
13592 int}. The resulting vector will be {double}, indicating that `T'
13593 is bound to `double'. */
13596 get_class_bindings (tree tparms, tree spec_args, tree args)
13598 int i, ntparms = TREE_VEC_LENGTH (tparms);
13600 tree innermost_deduced_args;
13602 innermost_deduced_args = make_tree_vec (ntparms);
13603 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
13605 deduced_args = copy_node (args);
13606 SET_TMPL_ARGS_LEVEL (deduced_args,
13607 TMPL_ARGS_DEPTH (deduced_args),
13608 innermost_deduced_args);
13611 deduced_args = innermost_deduced_args;
13613 if (unify (tparms, deduced_args,
13614 INNERMOST_TEMPLATE_ARGS (spec_args),
13615 INNERMOST_TEMPLATE_ARGS (args),
13619 for (i = 0; i < ntparms; ++i)
13620 if (! TREE_VEC_ELT (innermost_deduced_args, i))
13623 /* Verify that nondeduced template arguments agree with the type
13624 obtained from argument deduction.
13628 struct A { typedef int X; };
13629 template <class T, class U> struct C {};
13630 template <class T> struct C<T, typename T::X> {};
13632 Then with the instantiation `C<A, int>', we can deduce that
13633 `T' is `A' but unify () does not check whether `typename T::X'
13635 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
13636 if (spec_args == error_mark_node
13637 /* We only need to check the innermost arguments; the other
13638 arguments will always agree. */
13639 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
13640 INNERMOST_TEMPLATE_ARGS (args)))
13643 return deduced_args;
13646 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
13647 Return the TREE_LIST node with the most specialized template, if
13648 any. If there is no most specialized template, the error_mark_node
13651 Note that this function does not look at, or modify, the
13652 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
13653 returned is one of the elements of INSTANTIATIONS, callers may
13654 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
13655 and retrieve it from the value returned. */
13658 most_specialized_instantiation (tree templates)
13662 ++processing_template_decl;
13665 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
13669 if (get_bindings (TREE_VALUE (champ),
13670 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
13671 NULL_TREE, /*check_ret=*/false))
13674 if (get_bindings (TREE_VALUE (fn),
13675 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
13676 NULL_TREE, /*check_ret=*/false))
13683 /* Equally specialized, move to next function. If there
13684 is no next function, nothing's most specialized. */
13685 fn = TREE_CHAIN (fn);
13693 /* Now verify that champ is better than everything earlier in the
13694 instantiation list. */
13695 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
13696 if (get_bindings (TREE_VALUE (champ),
13697 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
13698 NULL_TREE, /*check_ret=*/false)
13699 || !get_bindings (TREE_VALUE (fn),
13700 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
13701 NULL_TREE, /*check_ret=*/false))
13707 processing_template_decl--;
13710 return error_mark_node;
13715 /* If DECL is a specialization of some template, return the most
13716 general such template. Otherwise, returns NULL_TREE.
13718 For example, given:
13720 template <class T> struct S { template <class U> void f(U); };
13722 if TMPL is `template <class U> void S<int>::f(U)' this will return
13723 the full template. This function will not trace past partial
13724 specializations, however. For example, given in addition:
13726 template <class T> struct S<T*> { template <class U> void f(U); };
13728 if TMPL is `template <class U> void S<int*>::f(U)' this will return
13729 `template <class T> template <class U> S<T*>::f(U)'. */
13732 most_general_template (tree decl)
13734 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
13735 an immediate specialization. */
13736 if (TREE_CODE (decl) == FUNCTION_DECL)
13738 if (DECL_TEMPLATE_INFO (decl)) {
13739 decl = DECL_TI_TEMPLATE (decl);
13741 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
13742 template friend. */
13743 if (TREE_CODE (decl) != TEMPLATE_DECL)
13749 /* Look for more and more general templates. */
13750 while (DECL_TEMPLATE_INFO (decl))
13752 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
13753 (See cp-tree.h for details.) */
13754 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
13757 if (CLASS_TYPE_P (TREE_TYPE (decl))
13758 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
13761 /* Stop if we run into an explicitly specialized class template. */
13762 if (!DECL_NAMESPACE_SCOPE_P (decl)
13763 && DECL_CONTEXT (decl)
13764 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
13767 decl = DECL_TI_TEMPLATE (decl);
13773 /* Return the most specialized of the class template partial
13774 specializations of TMPL which can produce TYPE, a specialization of
13775 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
13776 a _TYPE node corresponding to the partial specialization, while the
13777 TREE_PURPOSE is the set of template arguments that must be
13778 substituted into the TREE_TYPE in order to generate TYPE.
13780 If the choice of partial specialization is ambiguous, a diagnostic
13781 is issued, and the error_mark_node is returned. If there are no
13782 partial specializations of TMPL matching TYPE, then NULL_TREE is
13786 most_specialized_class (tree type, tree tmpl)
13788 tree list = NULL_TREE;
13794 tree outer_args = NULL_TREE;
13796 tmpl = most_general_template (tmpl);
13797 args = CLASSTYPE_TI_ARGS (type);
13799 /* For determining which partial specialization to use, only the
13800 innermost args are interesting. */
13801 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
13803 outer_args = strip_innermost_template_args (args, 1);
13804 args = INNERMOST_TEMPLATE_ARGS (args);
13807 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
13809 tree partial_spec_args;
13811 tree parms = TREE_VALUE (t);
13813 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
13818 ++processing_template_decl;
13820 /* Discard the outer levels of args, and then substitute in the
13821 template args from the enclosing class. */
13822 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
13823 partial_spec_args = tsubst_template_args
13824 (partial_spec_args, outer_args, tf_none, NULL_TREE);
13826 /* PARMS already refers to just the innermost parms, but the
13827 template parms in partial_spec_args had their levels lowered
13828 by tsubst, so we need to do the same for the parm list. We
13829 can't just tsubst the TREE_VEC itself, as tsubst wants to
13830 treat a TREE_VEC as an argument vector. */
13831 parms = copy_node (parms);
13832 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
13833 TREE_VEC_ELT (parms, i) =
13834 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
13836 --processing_template_decl;
13838 spec_args = get_class_bindings (parms,
13844 spec_args = add_to_template_args (outer_args, spec_args);
13845 list = tree_cons (spec_args, TREE_VALUE (t), list);
13846 TREE_TYPE (list) = TREE_TYPE (t);
13853 ambiguous_p = false;
13856 t = TREE_CHAIN (t);
13857 for (; t; t = TREE_CHAIN (t))
13859 fate = more_specialized_class (champ, t);
13866 t = TREE_CHAIN (t);
13869 ambiguous_p = true;
13878 for (t = list; t && t != champ; t = TREE_CHAIN (t))
13880 fate = more_specialized_class (champ, t);
13883 ambiguous_p = true;
13890 const char *str = "candidates are:";
13891 error ("ambiguous class template instantiation for %q#T", type);
13892 for (t = list; t; t = TREE_CHAIN (t))
13894 error ("%s %+#T", str, TREE_TYPE (t));
13897 return error_mark_node;
13903 /* Explicitly instantiate DECL. */
13906 do_decl_instantiation (tree decl, tree storage)
13908 tree result = NULL_TREE;
13911 if (!decl || decl == error_mark_node)
13912 /* An error occurred, for which grokdeclarator has already issued
13913 an appropriate message. */
13915 else if (! DECL_LANG_SPECIFIC (decl))
13917 error ("explicit instantiation of non-template %q#D", decl);
13920 else if (TREE_CODE (decl) == VAR_DECL)
13922 /* There is an asymmetry here in the way VAR_DECLs and
13923 FUNCTION_DECLs are handled by grokdeclarator. In the case of
13924 the latter, the DECL we get back will be marked as a
13925 template instantiation, and the appropriate
13926 DECL_TEMPLATE_INFO will be set up. This does not happen for
13927 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
13928 should handle VAR_DECLs as it currently handles
13930 if (!DECL_CLASS_SCOPE_P (decl))
13932 error ("%qD is not a static data member of a class template", decl);
13935 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
13936 if (!result || TREE_CODE (result) != VAR_DECL)
13938 error ("no matching template for %qD found", decl);
13941 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
13943 error ("type %qT for explicit instantiation %qD does not match "
13944 "declared type %qT", TREE_TYPE (result), decl,
13949 else if (TREE_CODE (decl) != FUNCTION_DECL)
13951 error ("explicit instantiation of %q#D", decl);
13957 /* Check for various error cases. Note that if the explicit
13958 instantiation is valid the RESULT will currently be marked as an
13959 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
13960 until we get here. */
13962 if (DECL_TEMPLATE_SPECIALIZATION (result))
13964 /* DR 259 [temp.spec].
13966 Both an explicit instantiation and a declaration of an explicit
13967 specialization shall not appear in a program unless the explicit
13968 instantiation follows a declaration of the explicit specialization.
13970 For a given set of template parameters, if an explicit
13971 instantiation of a template appears after a declaration of an
13972 explicit specialization for that template, the explicit
13973 instantiation has no effect. */
13976 else if (DECL_EXPLICIT_INSTANTIATION (result))
13980 No program shall explicitly instantiate any template more
13983 We check DECL_NOT_REALLY_EXTERN so as not to complain when
13984 the first instantiation was `extern' and the second is not,
13985 and EXTERN_P for the opposite case. */
13986 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
13987 pedwarn ("duplicate explicit instantiation of %q#D", result);
13988 /* If an "extern" explicit instantiation follows an ordinary
13989 explicit instantiation, the template is instantiated. */
13993 else if (!DECL_IMPLICIT_INSTANTIATION (result))
13995 error ("no matching template for %qD found", result);
13998 else if (!DECL_TEMPLATE_INFO (result))
14000 pedwarn ("explicit instantiation of non-template %q#D", result);
14004 if (storage == NULL_TREE)
14006 else if (storage == ridpointers[(int) RID_EXTERN])
14008 if (pedantic && !in_system_header)
14009 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
14014 error ("storage class %qD applied to template instantiation", storage);
14016 check_explicit_instantiation_namespace (result);
14017 mark_decl_instantiated (result, extern_p);
14019 instantiate_decl (result, /*defer_ok=*/1,
14020 /*expl_inst_class_mem_p=*/false);
14024 mark_class_instantiated (tree t, int extern_p)
14026 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
14027 SET_CLASSTYPE_INTERFACE_KNOWN (t);
14028 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
14029 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
14032 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
14033 rest_of_type_compilation (t, 1);
14037 /* Called from do_type_instantiation through binding_table_foreach to
14038 do recursive instantiation for the type bound in ENTRY. */
14040 bt_instantiate_type_proc (binding_entry entry, void *data)
14042 tree storage = *(tree *) data;
14044 if (IS_AGGR_TYPE (entry->type)
14045 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
14046 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
14049 /* Called from do_type_instantiation to instantiate a member
14050 (a member function or a static member variable) of an
14051 explicitly instantiated class template. */
14053 instantiate_class_member (tree decl, int extern_p)
14055 mark_decl_instantiated (decl, extern_p);
14057 instantiate_decl (decl, /*defer_ok=*/1,
14058 /*expl_inst_class_mem_p=*/true);
14061 /* Perform an explicit instantiation of template class T. STORAGE, if
14062 non-null, is the RID for extern, inline or static. COMPLAIN is
14063 nonzero if this is called from the parser, zero if called recursively,
14064 since the standard is unclear (as detailed below). */
14067 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
14072 int previous_instantiation_extern_p = 0;
14074 if (TREE_CODE (t) == TYPE_DECL)
14077 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
14079 error ("explicit instantiation of non-template type %qT", t);
14085 if (!COMPLETE_TYPE_P (t))
14087 if (complain & tf_error)
14088 error ("explicit instantiation of %q#T before definition of template",
14093 if (storage != NULL_TREE)
14095 if (pedantic && !in_system_header)
14096 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
14099 if (storage == ridpointers[(int) RID_INLINE])
14101 else if (storage == ridpointers[(int) RID_EXTERN])
14103 else if (storage == ridpointers[(int) RID_STATIC])
14107 error ("storage class %qD applied to template instantiation",
14113 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
14115 /* DR 259 [temp.spec].
14117 Both an explicit instantiation and a declaration of an explicit
14118 specialization shall not appear in a program unless the explicit
14119 instantiation follows a declaration of the explicit specialization.
14121 For a given set of template parameters, if an explicit
14122 instantiation of a template appears after a declaration of an
14123 explicit specialization for that template, the explicit
14124 instantiation has no effect. */
14127 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
14131 No program shall explicitly instantiate any template more
14134 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
14135 instantiation was `extern'. If EXTERN_P then the second is.
14136 These cases are OK. */
14137 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
14139 if (!previous_instantiation_extern_p && !extern_p
14140 && (complain & tf_error))
14141 pedwarn ("duplicate explicit instantiation of %q#T", t);
14143 /* If we've already instantiated the template, just return now. */
14144 if (!CLASSTYPE_INTERFACE_ONLY (t))
14148 check_explicit_instantiation_namespace (TYPE_NAME (t));
14149 mark_class_instantiated (t, extern_p);
14157 /* In contrast to implicit instantiation, where only the
14158 declarations, and not the definitions, of members are
14159 instantiated, we have here:
14163 The explicit instantiation of a class template specialization
14164 implies the instantiation of all of its members not
14165 previously explicitly specialized in the translation unit
14166 containing the explicit instantiation.
14168 Of course, we can't instantiate member template classes, since
14169 we don't have any arguments for them. Note that the standard
14170 is unclear on whether the instantiation of the members are
14171 *explicit* instantiations or not. However, the most natural
14172 interpretation is that it should be an explicit instantiation. */
14175 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
14176 if (TREE_CODE (tmp) == FUNCTION_DECL
14177 && DECL_TEMPLATE_INSTANTIATION (tmp))
14178 instantiate_class_member (tmp, extern_p);
14180 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
14181 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
14182 instantiate_class_member (tmp, extern_p);
14184 if (CLASSTYPE_NESTED_UTDS (t))
14185 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
14186 bt_instantiate_type_proc, &storage);
14190 /* Given a function DECL, which is a specialization of TMPL, modify
14191 DECL to be a re-instantiation of TMPL with the same template
14192 arguments. TMPL should be the template into which tsubst'ing
14193 should occur for DECL, not the most general template.
14195 One reason for doing this is a scenario like this:
14198 void f(const T&, int i);
14200 void g() { f(3, 7); }
14203 void f(const T& t, const int i) { }
14205 Note that when the template is first instantiated, with
14206 instantiate_template, the resulting DECL will have no name for the
14207 first parameter, and the wrong type for the second. So, when we go
14208 to instantiate the DECL, we regenerate it. */
14211 regenerate_decl_from_template (tree decl, tree tmpl)
14213 /* The arguments used to instantiate DECL, from the most general
14218 args = DECL_TI_ARGS (decl);
14219 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
14221 /* Make sure that we can see identifiers, and compute access
14223 push_access_scope (decl);
14225 if (TREE_CODE (decl) == FUNCTION_DECL)
14233 args_depth = TMPL_ARGS_DEPTH (args);
14234 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
14235 if (args_depth > parms_depth)
14236 args = get_innermost_template_args (args, parms_depth);
14238 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
14239 args, tf_error, NULL_TREE);
14241 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
14244 /* Merge parameter declarations. */
14245 decl_parm = skip_artificial_parms_for (decl,
14246 DECL_ARGUMENTS (decl));
14248 = skip_artificial_parms_for (code_pattern,
14249 DECL_ARGUMENTS (code_pattern));
14250 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
14255 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
14256 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
14257 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
14259 parm_type = type_decays_to (parm_type);
14260 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
14261 TREE_TYPE (decl_parm) = parm_type;
14262 attributes = DECL_ATTRIBUTES (pattern_parm);
14263 if (DECL_ATTRIBUTES (decl_parm) != attributes)
14265 DECL_ATTRIBUTES (decl_parm) = attributes;
14266 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
14268 decl_parm = TREE_CHAIN (decl_parm);
14269 pattern_parm = TREE_CHAIN (pattern_parm);
14271 /* Merge any parameters that match with the function parameter
14273 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
14276 tree expanded_types;
14277 /* Expand the TYPE_PACK_EXPANSION that provides the types for
14278 the parameters in this function parameter pack. */
14279 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
14280 args, tf_error, NULL_TREE);
14281 len = TREE_VEC_LENGTH (expanded_types);
14282 for (i = 0; i < len; i++)
14287 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
14288 /* Rename the parameter to include the index. */
14289 DECL_NAME (decl_parm) =
14290 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
14291 parm_type = TREE_VEC_ELT (expanded_types, i);
14292 parm_type = type_decays_to (parm_type);
14293 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
14294 TREE_TYPE (decl_parm) = parm_type;
14295 attributes = DECL_ATTRIBUTES (pattern_parm);
14296 if (DECL_ATTRIBUTES (decl_parm) != attributes)
14298 DECL_ATTRIBUTES (decl_parm) = attributes;
14299 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
14301 decl_parm = TREE_CHAIN (decl_parm);
14304 /* Merge additional specifiers from the CODE_PATTERN. */
14305 if (DECL_DECLARED_INLINE_P (code_pattern)
14306 && !DECL_DECLARED_INLINE_P (decl))
14307 DECL_DECLARED_INLINE_P (decl) = 1;
14308 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
14309 DECL_INLINE (decl) = 1;
14311 else if (TREE_CODE (decl) == VAR_DECL)
14312 DECL_INITIAL (decl) =
14313 tsubst_expr (DECL_INITIAL (code_pattern), args,
14314 tf_error, DECL_TI_TEMPLATE (decl),
14315 /*integral_constant_expression_p=*/false);
14317 gcc_unreachable ();
14319 pop_access_scope (decl);
14322 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
14323 substituted to get DECL. */
14326 template_for_substitution (tree decl)
14328 tree tmpl = DECL_TI_TEMPLATE (decl);
14330 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
14331 for the instantiation. This is not always the most general
14332 template. Consider, for example:
14335 struct S { template <class U> void f();
14336 template <> void f<int>(); };
14338 and an instantiation of S<double>::f<int>. We want TD to be the
14339 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
14340 while (/* An instantiation cannot have a definition, so we need a
14341 more general template. */
14342 DECL_TEMPLATE_INSTANTIATION (tmpl)
14343 /* We must also deal with friend templates. Given:
14345 template <class T> struct S {
14346 template <class U> friend void f() {};
14349 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
14350 so far as the language is concerned, but that's still
14351 where we get the pattern for the instantiation from. On
14352 other hand, if the definition comes outside the class, say:
14354 template <class T> struct S {
14355 template <class U> friend void f();
14357 template <class U> friend void f() {}
14359 we don't need to look any further. That's what the check for
14360 DECL_INITIAL is for. */
14361 || (TREE_CODE (decl) == FUNCTION_DECL
14362 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
14363 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
14365 /* The present template, TD, should not be a definition. If it
14366 were a definition, we should be using it! Note that we
14367 cannot restructure the loop to just keep going until we find
14368 a template with a definition, since that might go too far if
14369 a specialization was declared, but not defined. */
14370 gcc_assert (TREE_CODE (decl) != VAR_DECL
14371 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
14373 /* Fetch the more general template. */
14374 tmpl = DECL_TI_TEMPLATE (tmpl);
14380 /* Produce the definition of D, a _DECL generated from a template. If
14381 DEFER_OK is nonzero, then we don't have to actually do the
14382 instantiation now; we just have to do it sometime. Normally it is
14383 an error if this is an explicit instantiation but D is undefined.
14384 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
14385 explicitly instantiated class template. */
14388 instantiate_decl (tree d, int defer_ok,
14389 bool expl_inst_class_mem_p)
14391 tree tmpl = DECL_TI_TEMPLATE (d);
14398 bool pattern_defined;
14400 location_t saved_loc = input_location;
14401 int saved_in_system_header = in_system_header;
14404 /* This function should only be used to instantiate templates for
14405 functions and static member variables. */
14406 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
14407 || TREE_CODE (d) == VAR_DECL);
14409 /* Variables are never deferred; if instantiation is required, they
14410 are instantiated right away. That allows for better code in the
14411 case that an expression refers to the value of the variable --
14412 if the variable has a constant value the referring expression can
14413 take advantage of that fact. */
14414 if (TREE_CODE (d) == VAR_DECL)
14417 /* Don't instantiate cloned functions. Instead, instantiate the
14418 functions they cloned. */
14419 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
14420 d = DECL_CLONED_FUNCTION (d);
14422 if (DECL_TEMPLATE_INSTANTIATED (d))
14423 /* D has already been instantiated. It might seem reasonable to
14424 check whether or not D is an explicit instantiation, and, if so,
14425 stop here. But when an explicit instantiation is deferred
14426 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
14427 is set, even though we still need to do the instantiation. */
14430 /* If we already have a specialization of this declaration, then
14431 there's no reason to instantiate it. Note that
14432 retrieve_specialization gives us both instantiations and
14433 specializations, so we must explicitly check
14434 DECL_TEMPLATE_SPECIALIZATION. */
14435 gen_tmpl = most_general_template (tmpl);
14436 gen_args = DECL_TI_ARGS (d);
14437 spec = retrieve_specialization (gen_tmpl, gen_args,
14438 /*class_specializations_p=*/false);
14439 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
14442 /* This needs to happen before any tsubsting. */
14443 if (! push_tinst_level (d))
14446 timevar_push (TV_PARSE);
14448 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
14449 for the instantiation. */
14450 td = template_for_substitution (d);
14451 code_pattern = DECL_TEMPLATE_RESULT (td);
14453 /* We should never be trying to instantiate a member of a class
14454 template or partial specialization. */
14455 gcc_assert (d != code_pattern);
14457 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
14458 || DECL_TEMPLATE_SPECIALIZATION (td))
14459 /* In the case of a friend template whose definition is provided
14460 outside the class, we may have too many arguments. Drop the
14461 ones we don't need. The same is true for specializations. */
14462 args = get_innermost_template_args
14463 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
14467 if (TREE_CODE (d) == FUNCTION_DECL)
14468 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
14470 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
14472 /* We may be in the middle of deferred access check. Disable it now. */
14473 push_deferring_access_checks (dk_no_deferred);
14475 /* Unless an explicit instantiation directive has already determined
14476 the linkage of D, remember that a definition is available for
14478 if (pattern_defined
14479 && !DECL_INTERFACE_KNOWN (d)
14480 && !DECL_NOT_REALLY_EXTERN (d))
14481 mark_definable (d);
14483 input_location = DECL_SOURCE_LOCATION (d);
14484 in_system_header = DECL_IN_SYSTEM_HEADER (d);
14486 /* If D is a member of an explicitly instantiated class template,
14487 and no definition is available, treat it like an implicit
14489 if (!pattern_defined && expl_inst_class_mem_p
14490 && DECL_EXPLICIT_INSTANTIATION (d))
14492 DECL_NOT_REALLY_EXTERN (d) = 0;
14493 DECL_INTERFACE_KNOWN (d) = 0;
14494 SET_DECL_IMPLICIT_INSTANTIATION (d);
14499 /* Recheck the substitutions to obtain any warning messages
14500 about ignoring cv qualifiers. */
14501 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
14502 tree type = TREE_TYPE (gen);
14504 /* Make sure that we can see identifiers, and compute access
14505 correctly. D is already the target FUNCTION_DECL with the
14507 push_access_scope (d);
14509 if (TREE_CODE (gen) == FUNCTION_DECL)
14511 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
14512 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
14514 /* Don't simply tsubst the function type, as that will give
14515 duplicate warnings about poor parameter qualifications.
14516 The function arguments are the same as the decl_arguments
14517 without the top level cv qualifiers. */
14518 type = TREE_TYPE (type);
14520 tsubst (type, gen_args, tf_warning_or_error, d);
14522 pop_access_scope (d);
14525 /* Check to see whether we know that this template will be
14526 instantiated in some other file, as with "extern template"
14528 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
14529 /* In general, we do not instantiate such templates... */
14531 /* ... but we instantiate inline functions so that we can inline
14533 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
14534 /* ... we instantiate static data members whose values are
14535 needed in integral constant expressions. */
14536 && ! (TREE_CODE (d) == VAR_DECL
14537 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
14539 /* Defer all other templates, unless we have been explicitly
14540 forbidden from doing so. */
14541 if (/* If there is no definition, we cannot instantiate the
14544 /* If it's OK to postpone instantiation, do so. */
14546 /* If this is a static data member that will be defined
14547 elsewhere, we don't want to instantiate the entire data
14548 member, but we do want to instantiate the initializer so that
14549 we can substitute that elsewhere. */
14550 || (external_p && TREE_CODE (d) == VAR_DECL))
14552 /* The definition of the static data member is now required so
14553 we must substitute the initializer. */
14554 if (TREE_CODE (d) == VAR_DECL
14555 && !DECL_INITIAL (d)
14556 && DECL_INITIAL (code_pattern))
14561 ns = decl_namespace_context (d);
14562 push_nested_namespace (ns);
14563 push_nested_class (DECL_CONTEXT (d));
14564 init = tsubst_expr (DECL_INITIAL (code_pattern),
14566 tf_warning_or_error, NULL_TREE,
14567 /*integral_constant_expression_p=*/false);
14568 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
14569 /*asmspec_tree=*/NULL_TREE,
14570 LOOKUP_ONLYCONVERTING);
14571 pop_nested_class ();
14572 pop_nested_namespace (ns);
14575 /* We restore the source position here because it's used by
14576 add_pending_template. */
14577 input_location = saved_loc;
14579 if (at_eof && !pattern_defined
14580 && DECL_EXPLICIT_INSTANTIATION (d))
14583 The definition of a non-exported function template, a
14584 non-exported member function template, or a non-exported
14585 member function or static data member of a class template
14586 shall be present in every translation unit in which it is
14587 explicitly instantiated. */
14589 ("explicit instantiation of %qD but no definition available", d);
14591 /* ??? Historically, we have instantiated inline functions, even
14592 when marked as "extern template". */
14593 if (!(external_p && TREE_CODE (d) == VAR_DECL))
14594 add_pending_template (d);
14597 /* Tell the repository that D is available in this translation unit
14598 -- and see if it is supposed to be instantiated here. */
14599 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
14601 /* In a PCH file, despite the fact that the repository hasn't
14602 requested instantiation in the PCH it is still possible that
14603 an instantiation will be required in a file that includes the
14606 add_pending_template (d);
14607 /* Instantiate inline functions so that the inliner can do its
14608 job, even though we'll not be emitting a copy of this
14610 if (!(TREE_CODE (d) == FUNCTION_DECL
14611 && flag_inline_trees
14612 && DECL_DECLARED_INLINE_P (d)))
14616 need_push = !cfun || !global_bindings_p ();
14618 push_to_top_level ();
14620 /* Mark D as instantiated so that recursive calls to
14621 instantiate_decl do not try to instantiate it again. */
14622 DECL_TEMPLATE_INSTANTIATED (d) = 1;
14624 /* Regenerate the declaration in case the template has been modified
14625 by a subsequent redeclaration. */
14626 regenerate_decl_from_template (d, td);
14628 /* We already set the file and line above. Reset them now in case
14629 they changed as a result of calling regenerate_decl_from_template. */
14630 input_location = DECL_SOURCE_LOCATION (d);
14632 if (TREE_CODE (d) == VAR_DECL)
14636 /* Clear out DECL_RTL; whatever was there before may not be right
14637 since we've reset the type of the declaration. */
14638 SET_DECL_RTL (d, NULL_RTX);
14639 DECL_IN_AGGR_P (d) = 0;
14641 /* The initializer is placed in DECL_INITIAL by
14642 regenerate_decl_from_template. Pull it out so that
14643 finish_decl can process it. */
14644 init = DECL_INITIAL (d);
14645 DECL_INITIAL (d) = NULL_TREE;
14646 DECL_INITIALIZED_P (d) = 0;
14648 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
14649 initializer. That function will defer actual emission until
14650 we have a chance to determine linkage. */
14651 DECL_EXTERNAL (d) = 0;
14653 /* Enter the scope of D so that access-checking works correctly. */
14654 push_nested_class (DECL_CONTEXT (d));
14655 finish_decl (d, init, NULL_TREE);
14656 pop_nested_class ();
14658 else if (TREE_CODE (d) == FUNCTION_DECL)
14660 htab_t saved_local_specializations;
14665 /* Save away the current list, in case we are instantiating one
14666 template from within the body of another. */
14667 saved_local_specializations = local_specializations;
14669 /* Set up the list of local specializations. */
14670 local_specializations = htab_create (37,
14671 hash_local_specialization,
14672 eq_local_specializations,
14675 /* Set up context. */
14676 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
14678 /* Create substitution entries for the parameters. */
14679 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
14680 tmpl_parm = DECL_ARGUMENTS (subst_decl);
14681 spec_parm = DECL_ARGUMENTS (d);
14682 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
14684 register_local_specialization (spec_parm, tmpl_parm);
14685 spec_parm = skip_artificial_parms_for (d, spec_parm);
14686 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
14688 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
14690 register_local_specialization (spec_parm, tmpl_parm);
14691 tmpl_parm = TREE_CHAIN (tmpl_parm);
14692 spec_parm = TREE_CHAIN (spec_parm);
14694 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
14696 /* Collect all of the extra "packed" parameters into an
14700 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
14701 tree argtypepack = make_node (TYPE_ARGUMENT_PACK);
14705 /* Count how many parameters remain. */
14706 for (t = spec_parm; t; t = TREE_CHAIN (t))
14709 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
14710 parmvec = make_tree_vec (len);
14711 parmtypevec = make_tree_vec (len);
14712 for(i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
14714 TREE_VEC_ELT (parmvec, i) = spec_parm;
14715 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
14718 /* Build the argument packs. */
14719 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
14720 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
14721 TREE_TYPE (argpack) = argtypepack;
14723 /* Register the (value) argument pack as a specialization of
14724 TMPL_PARM, then move on. */
14725 register_local_specialization (argpack, tmpl_parm);
14726 tmpl_parm = TREE_CHAIN (tmpl_parm);
14728 gcc_assert (!spec_parm);
14730 /* Substitute into the body of the function. */
14731 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
14732 tf_warning_or_error, tmpl,
14733 /*integral_constant_expression_p=*/false);
14735 /* Set the current input_location to the end of the function
14736 so that finish_function knows where we are. */
14737 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
14739 /* We don't need the local specializations any more. */
14740 htab_delete (local_specializations);
14741 local_specializations = saved_local_specializations;
14743 /* Finish the function. */
14744 d = finish_function (0);
14745 expand_or_defer_fn (d);
14748 /* We're not deferring instantiation any more. */
14749 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
14752 pop_from_top_level ();
14755 input_location = saved_loc;
14756 in_system_header = saved_in_system_header;
14757 pop_deferring_access_checks ();
14758 pop_tinst_level ();
14760 timevar_pop (TV_PARSE);
14765 /* Run through the list of templates that we wish we could
14766 instantiate, and instantiate any we can. RETRIES is the
14767 number of times we retry pending template instantiation. */
14770 instantiate_pending_templates (int retries)
14773 location_t saved_loc = input_location;
14774 int saved_in_system_header = in_system_header;
14776 /* Instantiating templates may trigger vtable generation. This in turn
14777 may require further template instantiations. We place a limit here
14778 to avoid infinite loop. */
14779 if (pending_templates && retries >= max_tinst_depth)
14781 tree decl = pending_templates->tinst->decl;
14783 error ("template instantiation depth exceeds maximum of %d"
14784 " instantiating %q+D, possibly from virtual table generation"
14785 " (use -ftemplate-depth-NN to increase the maximum)",
14786 max_tinst_depth, decl);
14787 if (TREE_CODE (decl) == FUNCTION_DECL)
14788 /* Pretend that we defined it. */
14789 DECL_INITIAL (decl) = error_mark_node;
14795 struct pending_template **t = &pending_templates;
14796 struct pending_template *last = NULL;
14800 tree instantiation = reopen_tinst_level ((*t)->tinst);
14801 bool complete = false;
14803 if (TYPE_P (instantiation))
14807 if (!COMPLETE_TYPE_P (instantiation))
14809 instantiate_class_template (instantiation);
14810 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
14811 for (fn = TYPE_METHODS (instantiation);
14813 fn = TREE_CHAIN (fn))
14814 if (! DECL_ARTIFICIAL (fn))
14815 instantiate_decl (fn,
14817 /*expl_inst_class_mem_p=*/false);
14818 if (COMPLETE_TYPE_P (instantiation))
14822 complete = COMPLETE_TYPE_P (instantiation);
14826 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
14827 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
14830 = instantiate_decl (instantiation,
14832 /*expl_inst_class_mem_p=*/false);
14833 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
14837 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
14838 || DECL_TEMPLATE_INSTANTIATED (instantiation));
14842 /* If INSTANTIATION has been instantiated, then we don't
14843 need to consider it again in the future. */
14851 current_tinst_level = NULL;
14853 last_pending_template = last;
14855 while (reconsider);
14857 input_location = saved_loc;
14858 in_system_header = saved_in_system_header;
14861 /* Substitute ARGVEC into T, which is a list of initializers for
14862 either base class or a non-static data member. The TREE_PURPOSEs
14863 are DECLs, and the TREE_VALUEs are the initializer values. Used by
14864 instantiate_decl. */
14867 tsubst_initializer_list (tree t, tree argvec)
14869 tree inits = NULL_TREE;
14871 for (; t; t = TREE_CHAIN (t))
14875 tree expanded_bases = NULL_TREE;
14876 tree expanded_arguments = NULL_TREE;
14879 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
14884 /* Expand the base class expansion type into separate base
14886 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
14887 tf_warning_or_error,
14889 if (expanded_bases == error_mark_node)
14892 /* We'll be building separate TREE_LISTs of arguments for
14894 len = TREE_VEC_LENGTH (expanded_bases);
14895 expanded_arguments = make_tree_vec (len);
14896 for (i = 0; i < len; i++)
14897 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
14899 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
14900 expand each argument in the TREE_VALUE of t. */
14901 expr = make_node (EXPR_PACK_EXPANSION);
14902 PACK_EXPANSION_PARAMETER_PACKS (expr) =
14903 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
14905 /* Substitute parameter packs into each argument in the
14907 in_base_initializer = 1;
14908 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
14910 tree expanded_exprs;
14912 /* Expand the argument. */
14913 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
14914 expanded_exprs = tsubst_pack_expansion (expr, argvec,
14915 tf_warning_or_error,
14918 /* Prepend each of the expanded expressions to the
14919 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
14920 for (i = 0; i < len; i++)
14922 TREE_VEC_ELT (expanded_arguments, i) =
14923 tree_cons (NULL_TREE, TREE_VEC_ELT (expanded_exprs, i),
14924 TREE_VEC_ELT (expanded_arguments, i));
14927 in_base_initializer = 0;
14929 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
14930 since we built them backwards. */
14931 for (i = 0; i < len; i++)
14933 TREE_VEC_ELT (expanded_arguments, i) =
14934 nreverse (TREE_VEC_ELT (expanded_arguments, i));
14938 for (i = 0; i < len; ++i)
14940 if (expanded_bases)
14942 decl = TREE_VEC_ELT (expanded_bases, i);
14943 decl = expand_member_init (decl);
14944 init = TREE_VEC_ELT (expanded_arguments, i);
14948 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
14949 tf_warning_or_error, NULL_TREE);
14951 decl = expand_member_init (decl);
14952 if (decl && !DECL_P (decl))
14953 in_base_initializer = 1;
14955 init = tsubst_expr (TREE_VALUE (t), argvec,
14956 tf_warning_or_error, NULL_TREE,
14957 /*integral_constant_expression_p=*/false);
14958 in_base_initializer = 0;
14963 init = build_tree_list (decl, init);
14964 TREE_CHAIN (init) = inits;
14972 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
14975 set_current_access_from_decl (tree decl)
14977 if (TREE_PRIVATE (decl))
14978 current_access_specifier = access_private_node;
14979 else if (TREE_PROTECTED (decl))
14980 current_access_specifier = access_protected_node;
14982 current_access_specifier = access_public_node;
14985 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
14986 is the instantiation (which should have been created with
14987 start_enum) and ARGS are the template arguments to use. */
14990 tsubst_enum (tree tag, tree newtag, tree args)
14994 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
14999 decl = TREE_VALUE (e);
15000 /* Note that in a template enum, the TREE_VALUE is the
15001 CONST_DECL, not the corresponding INTEGER_CST. */
15002 value = tsubst_expr (DECL_INITIAL (decl),
15003 args, tf_warning_or_error, NULL_TREE,
15004 /*integral_constant_expression_p=*/true);
15006 /* Give this enumeration constant the correct access. */
15007 set_current_access_from_decl (decl);
15009 /* Actually build the enumerator itself. */
15010 build_enumerator (DECL_NAME (decl), value, newtag);
15013 finish_enum (newtag);
15014 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
15015 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
15018 /* DECL is a FUNCTION_DECL that is a template specialization. Return
15019 its type -- but without substituting the innermost set of template
15020 arguments. So, innermost set of template parameters will appear in
15024 get_mostly_instantiated_function_type (tree decl)
15032 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
15033 targs = DECL_TI_ARGS (decl);
15034 tparms = DECL_TEMPLATE_PARMS (tmpl);
15035 parm_depth = TMPL_PARMS_DEPTH (tparms);
15037 /* There should be as many levels of arguments as there are levels
15039 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
15041 fn_type = TREE_TYPE (tmpl);
15043 if (parm_depth == 1)
15044 /* No substitution is necessary. */
15048 int i, save_access_control;
15051 /* Replace the innermost level of the TARGS with NULL_TREEs to
15052 let tsubst know not to substitute for those parameters. */
15053 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
15054 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
15055 SET_TMPL_ARGS_LEVEL (partial_args, i,
15056 TMPL_ARGS_LEVEL (targs, i));
15057 SET_TMPL_ARGS_LEVEL (partial_args,
15058 TMPL_ARGS_DEPTH (targs),
15059 make_tree_vec (DECL_NTPARMS (tmpl)));
15061 /* Disable access control as this function is used only during
15063 save_access_control = flag_access_control;
15064 flag_access_control = 0;
15066 ++processing_template_decl;
15067 /* Now, do the (partial) substitution to figure out the
15068 appropriate function type. */
15069 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
15070 --processing_template_decl;
15072 /* Substitute into the template parameters to obtain the real
15073 innermost set of parameters. This step is important if the
15074 innermost set of template parameters contains value
15075 parameters whose types depend on outer template parameters. */
15076 TREE_VEC_LENGTH (partial_args)--;
15077 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
15079 flag_access_control = save_access_control;
15085 /* Return truthvalue if we're processing a template different from
15086 the last one involved in diagnostics. */
15088 problematic_instantiation_changed (void)
15090 return last_template_error_tick != tinst_level_tick;
15093 /* Remember current template involved in diagnostics. */
15095 record_last_problematic_instantiation (void)
15097 last_template_error_tick = tinst_level_tick;
15100 struct tinst_level *
15101 current_instantiation (void)
15103 return current_tinst_level;
15106 /* [temp.param] Check that template non-type parm TYPE is of an allowable
15107 type. Return zero for ok, nonzero for disallowed. Issue error and
15108 warning messages under control of COMPLAIN. */
15111 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
15113 if (INTEGRAL_TYPE_P (type))
15115 else if (POINTER_TYPE_P (type))
15117 else if (TYPE_PTR_TO_MEMBER_P (type))
15119 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
15121 else if (TREE_CODE (type) == TYPENAME_TYPE)
15124 if (complain & tf_error)
15125 error ("%q#T is not a valid type for a template constant parameter", type);
15129 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
15130 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
15133 dependent_type_p_r (tree type)
15139 A type is dependent if it is:
15141 -- a template parameter. Template template parameters are types
15142 for us (since TYPE_P holds true for them) so we handle
15144 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
15145 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
15147 /* -- a qualified-id with a nested-name-specifier which contains a
15148 class-name that names a dependent type or whose unqualified-id
15149 names a dependent type. */
15150 if (TREE_CODE (type) == TYPENAME_TYPE)
15152 /* -- a cv-qualified type where the cv-unqualified type is
15154 type = TYPE_MAIN_VARIANT (type);
15155 /* -- a compound type constructed from any dependent type. */
15156 if (TYPE_PTR_TO_MEMBER_P (type))
15157 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
15158 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
15160 else if (TREE_CODE (type) == POINTER_TYPE
15161 || TREE_CODE (type) == REFERENCE_TYPE)
15162 return dependent_type_p (TREE_TYPE (type));
15163 else if (TREE_CODE (type) == FUNCTION_TYPE
15164 || TREE_CODE (type) == METHOD_TYPE)
15168 if (dependent_type_p (TREE_TYPE (type)))
15170 for (arg_type = TYPE_ARG_TYPES (type);
15172 arg_type = TREE_CHAIN (arg_type))
15173 if (dependent_type_p (TREE_VALUE (arg_type)))
15177 /* -- an array type constructed from any dependent type or whose
15178 size is specified by a constant expression that is
15179 value-dependent. */
15180 if (TREE_CODE (type) == ARRAY_TYPE)
15182 if (TYPE_DOMAIN (type)
15183 && ((value_dependent_expression_p
15184 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
15185 || (type_dependent_expression_p
15186 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
15188 return dependent_type_p (TREE_TYPE (type));
15191 /* -- a template-id in which either the template name is a template
15193 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
15195 /* ... or any of the template arguments is a dependent type or
15196 an expression that is type-dependent or value-dependent. */
15197 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
15198 && (any_dependent_template_arguments_p
15199 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
15202 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
15203 argument of the `typeof' expression is not type-dependent, then
15204 it should already been have resolved. */
15205 if (TREE_CODE (type) == TYPEOF_TYPE
15206 || TREE_CODE (type) == DECLTYPE_TYPE)
15209 /* A template argument pack is dependent if any of its packed
15211 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
15213 tree args = ARGUMENT_PACK_ARGS (type);
15214 int i, len = TREE_VEC_LENGTH (args);
15215 for (i = 0; i < len; ++i)
15216 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
15220 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
15221 be template parameters. */
15222 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
15225 /* The standard does not specifically mention types that are local
15226 to template functions or local classes, but they should be
15227 considered dependent too. For example:
15229 template <int I> void f() {
15234 The size of `E' cannot be known until the value of `I' has been
15235 determined. Therefore, `E' must be considered dependent. */
15236 scope = TYPE_CONTEXT (type);
15237 if (scope && TYPE_P (scope))
15238 return dependent_type_p (scope);
15239 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
15240 return type_dependent_expression_p (scope);
15242 /* Other types are non-dependent. */
15246 /* Returns TRUE if TYPE is dependent, in the sense of
15247 [temp.dep.type]. */
15250 dependent_type_p (tree type)
15252 /* If there are no template parameters in scope, then there can't be
15253 any dependent types. */
15254 if (!processing_template_decl)
15256 /* If we are not processing a template, then nobody should be
15257 providing us with a dependent type. */
15259 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM);
15263 /* If the type is NULL, we have not computed a type for the entity
15264 in question; in that case, the type is dependent. */
15268 /* Erroneous types can be considered non-dependent. */
15269 if (type == error_mark_node)
15272 /* If we have not already computed the appropriate value for TYPE,
15274 if (!TYPE_DEPENDENT_P_VALID (type))
15276 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
15277 TYPE_DEPENDENT_P_VALID (type) = 1;
15280 return TYPE_DEPENDENT_P (type);
15283 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
15286 dependent_scope_ref_p (tree expression, bool criterion (tree))
15291 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
15293 if (!TYPE_P (TREE_OPERAND (expression, 0)))
15296 scope = TREE_OPERAND (expression, 0);
15297 name = TREE_OPERAND (expression, 1);
15301 An id-expression is type-dependent if it contains a
15302 nested-name-specifier that contains a class-name that names a
15304 /* The suggested resolution to Core Issue 2 implies that if the
15305 qualifying type is the current class, then we must peek
15308 && currently_open_class (scope)
15309 && !criterion (name))
15311 if (dependent_type_p (scope))
15317 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
15318 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
15322 value_dependent_expression_p (tree expression)
15324 if (!processing_template_decl)
15327 /* A name declared with a dependent type. */
15328 if (DECL_P (expression) && type_dependent_expression_p (expression))
15331 switch (TREE_CODE (expression))
15333 case IDENTIFIER_NODE:
15334 /* A name that has not been looked up -- must be dependent. */
15337 case TEMPLATE_PARM_INDEX:
15338 /* A non-type template parm. */
15342 /* A non-type template parm. */
15343 if (DECL_TEMPLATE_PARM_P (expression))
15348 /* A constant with integral or enumeration type and is initialized
15349 with an expression that is value-dependent. */
15350 if (DECL_INITIAL (expression)
15351 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
15352 && value_dependent_expression_p (DECL_INITIAL (expression)))
15356 case DYNAMIC_CAST_EXPR:
15357 case STATIC_CAST_EXPR:
15358 case CONST_CAST_EXPR:
15359 case REINTERPRET_CAST_EXPR:
15361 /* These expressions are value-dependent if the type to which
15362 the cast occurs is dependent or the expression being casted
15363 is value-dependent. */
15365 tree type = TREE_TYPE (expression);
15367 if (dependent_type_p (type))
15370 /* A functional cast has a list of operands. */
15371 expression = TREE_OPERAND (expression, 0);
15374 /* If there are no operands, it must be an expression such
15375 as "int()". This should not happen for aggregate types
15376 because it would form non-constant expressions. */
15377 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
15382 if (TREE_CODE (expression) == TREE_LIST)
15383 return any_value_dependent_elements_p (expression);
15385 return value_dependent_expression_p (expression);
15390 /* A `sizeof' expression is value-dependent if the operand is
15391 type-dependent or is a pack expansion. */
15392 expression = TREE_OPERAND (expression, 0);
15393 if (PACK_EXPANSION_P (expression))
15395 else if (TYPE_P (expression))
15396 return dependent_type_p (expression);
15397 return type_dependent_expression_p (expression);
15400 return dependent_scope_ref_p (expression, value_dependent_expression_p);
15402 case COMPONENT_REF:
15403 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
15404 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
15407 /* A CALL_EXPR may appear in a constant expression if it is a
15408 call to a builtin function, e.g., __builtin_constant_p. All
15409 such calls are value-dependent. */
15412 case NONTYPE_ARGUMENT_PACK:
15413 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
15414 is value-dependent. */
15416 tree values = ARGUMENT_PACK_ARGS (expression);
15417 int i, len = TREE_VEC_LENGTH (values);
15419 for (i = 0; i < len; ++i)
15420 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
15428 tree type2 = TRAIT_EXPR_TYPE2 (expression);
15429 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
15430 || (type2 ? dependent_type_p (type2) : false));
15434 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
15435 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
15438 /* A constant expression is value-dependent if any subexpression is
15439 value-dependent. */
15440 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
15442 case tcc_reference:
15444 return (value_dependent_expression_p
15445 (TREE_OPERAND (expression, 0)));
15447 case tcc_comparison:
15449 return ((value_dependent_expression_p
15450 (TREE_OPERAND (expression, 0)))
15451 || (value_dependent_expression_p
15452 (TREE_OPERAND (expression, 1))));
15454 case tcc_expression:
15458 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
15459 /* In some cases, some of the operands may be missing.
15460 (For example, in the case of PREDECREMENT_EXPR, the
15461 amount to increment by may be missing.) That doesn't
15462 make the expression dependent. */
15463 if (TREE_OPERAND (expression, i)
15464 && (value_dependent_expression_p
15465 (TREE_OPERAND (expression, i))))
15475 /* The expression is not value-dependent. */
15479 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
15480 [temp.dep.expr]. */
15483 type_dependent_expression_p (tree expression)
15485 if (!processing_template_decl)
15488 if (expression == error_mark_node)
15491 /* An unresolved name is always dependent. */
15492 if (TREE_CODE (expression) == IDENTIFIER_NODE
15493 || TREE_CODE (expression) == USING_DECL)
15496 /* Some expression forms are never type-dependent. */
15497 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
15498 || TREE_CODE (expression) == SIZEOF_EXPR
15499 || TREE_CODE (expression) == ALIGNOF_EXPR
15500 || TREE_CODE (expression) == TRAIT_EXPR
15501 || TREE_CODE (expression) == TYPEID_EXPR
15502 || TREE_CODE (expression) == DELETE_EXPR
15503 || TREE_CODE (expression) == VEC_DELETE_EXPR
15504 || TREE_CODE (expression) == THROW_EXPR)
15507 /* The types of these expressions depends only on the type to which
15508 the cast occurs. */
15509 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
15510 || TREE_CODE (expression) == STATIC_CAST_EXPR
15511 || TREE_CODE (expression) == CONST_CAST_EXPR
15512 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
15513 || TREE_CODE (expression) == CAST_EXPR)
15514 return dependent_type_p (TREE_TYPE (expression));
15516 /* The types of these expressions depends only on the type created
15517 by the expression. */
15518 if (TREE_CODE (expression) == NEW_EXPR
15519 || TREE_CODE (expression) == VEC_NEW_EXPR)
15521 /* For NEW_EXPR tree nodes created inside a template, either
15522 the object type itself or a TREE_LIST may appear as the
15524 tree type = TREE_OPERAND (expression, 1);
15525 if (TREE_CODE (type) == TREE_LIST)
15526 /* This is an array type. We need to check array dimensions
15528 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
15529 || value_dependent_expression_p
15530 (TREE_OPERAND (TREE_VALUE (type), 1));
15532 return dependent_type_p (type);
15535 if (TREE_CODE (expression) == SCOPE_REF
15536 && dependent_scope_ref_p (expression,
15537 type_dependent_expression_p))
15540 if (TREE_CODE (expression) == FUNCTION_DECL
15541 && DECL_LANG_SPECIFIC (expression)
15542 && DECL_TEMPLATE_INFO (expression)
15543 && (any_dependent_template_arguments_p
15544 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
15547 if (TREE_CODE (expression) == TEMPLATE_DECL
15548 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
15551 if (TREE_CODE (expression) == STMT_EXPR)
15552 expression = stmt_expr_value_expr (expression);
15554 if (TREE_TYPE (expression) == unknown_type_node)
15556 if (TREE_CODE (expression) == ADDR_EXPR)
15557 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
15558 if (TREE_CODE (expression) == COMPONENT_REF
15559 || TREE_CODE (expression) == OFFSET_REF)
15561 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
15563 expression = TREE_OPERAND (expression, 1);
15564 if (TREE_CODE (expression) == IDENTIFIER_NODE)
15567 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
15568 if (TREE_CODE (expression) == SCOPE_REF)
15571 if (TREE_CODE (expression) == BASELINK)
15572 expression = BASELINK_FUNCTIONS (expression);
15574 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
15576 if (any_dependent_template_arguments_p
15577 (TREE_OPERAND (expression, 1)))
15579 expression = TREE_OPERAND (expression, 0);
15581 gcc_assert (TREE_CODE (expression) == OVERLOAD
15582 || TREE_CODE (expression) == FUNCTION_DECL);
15586 if (type_dependent_expression_p (OVL_CURRENT (expression)))
15588 expression = OVL_NEXT (expression);
15593 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
15595 return (dependent_type_p (TREE_TYPE (expression)));
15598 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
15599 contains a type-dependent expression. */
15602 any_type_dependent_arguments_p (const_tree args)
15606 tree arg = TREE_VALUE (args);
15608 if (type_dependent_expression_p (arg))
15610 args = TREE_CHAIN (args);
15615 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
15616 expressions) contains any value-dependent expressions. */
15619 any_value_dependent_elements_p (const_tree list)
15621 for (; list; list = TREE_CHAIN (list))
15622 if (value_dependent_expression_p (TREE_VALUE (list)))
15628 /* Returns TRUE if the ARG (a template argument) is dependent. */
15631 dependent_template_arg_p (tree arg)
15633 if (!processing_template_decl)
15636 if (TREE_CODE (arg) == TEMPLATE_DECL
15637 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
15638 return dependent_template_p (arg);
15639 else if (ARGUMENT_PACK_P (arg))
15641 tree args = ARGUMENT_PACK_ARGS (arg);
15642 int i, len = TREE_VEC_LENGTH (args);
15643 for (i = 0; i < len; ++i)
15645 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
15651 else if (TYPE_P (arg))
15652 return dependent_type_p (arg);
15654 return (type_dependent_expression_p (arg)
15655 || value_dependent_expression_p (arg));
15658 /* Returns true if ARGS (a collection of template arguments) contains
15659 any types that require structural equality testing. */
15662 any_template_arguments_need_structural_equality_p (tree args)
15669 if (args == error_mark_node)
15672 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
15674 tree level = TMPL_ARGS_LEVEL (args, i + 1);
15675 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
15677 tree arg = TREE_VEC_ELT (level, j);
15678 tree packed_args = NULL_TREE;
15681 if (ARGUMENT_PACK_P (arg))
15683 /* Look inside the argument pack. */
15684 packed_args = ARGUMENT_PACK_ARGS (arg);
15685 len = TREE_VEC_LENGTH (packed_args);
15688 for (k = 0; k < len; ++k)
15691 arg = TREE_VEC_ELT (packed_args, k);
15693 if (error_operand_p (arg))
15695 else if (TREE_CODE (arg) == TEMPLATE_DECL
15696 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
15698 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
15700 else if (!TYPE_P (arg) && TREE_TYPE (arg)
15701 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
15710 /* Returns true if ARGS (a collection of template arguments) contains
15711 any dependent arguments. */
15714 any_dependent_template_arguments_p (const_tree args)
15721 if (args == error_mark_node)
15724 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
15726 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
15727 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
15728 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
15735 /* Returns TRUE if the template TMPL is dependent. */
15738 dependent_template_p (tree tmpl)
15740 if (TREE_CODE (tmpl) == OVERLOAD)
15744 if (dependent_template_p (OVL_FUNCTION (tmpl)))
15746 tmpl = OVL_CHAIN (tmpl);
15751 /* Template template parameters are dependent. */
15752 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
15753 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
15755 /* So are names that have not been looked up. */
15756 if (TREE_CODE (tmpl) == SCOPE_REF
15757 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
15759 /* So are member templates of dependent classes. */
15760 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
15761 return dependent_type_p (DECL_CONTEXT (tmpl));
15765 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
15768 dependent_template_id_p (tree tmpl, tree args)
15770 return (dependent_template_p (tmpl)
15771 || any_dependent_template_arguments_p (args));
15774 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
15775 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
15776 no such TYPE can be found. Note that this function peers inside
15777 uninstantiated templates and therefore should be used only in
15778 extremely limited situations. ONLY_CURRENT_P restricts this
15779 peering to the currently open classes hierarchy (which is required
15780 when comparing types). */
15783 resolve_typename_type (tree type, bool only_current_p)
15792 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
15794 scope = TYPE_CONTEXT (type);
15795 name = TYPE_IDENTIFIER (type);
15797 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
15798 it first before we can figure out what NAME refers to. */
15799 if (TREE_CODE (scope) == TYPENAME_TYPE)
15800 scope = resolve_typename_type (scope, only_current_p);
15801 /* If we don't know what SCOPE refers to, then we cannot resolve the
15803 if (TREE_CODE (scope) == TYPENAME_TYPE)
15805 /* If the SCOPE is a template type parameter, we have no way of
15806 resolving the name. */
15807 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
15809 /* If the SCOPE is not the current instantiation, there's no reason
15810 to look inside it. */
15811 if (only_current_p && !currently_open_class (scope))
15813 /* If SCOPE isn't the template itself, it will not have a valid
15814 TYPE_FIELDS list. */
15815 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
15816 /* scope is either the template itself or a compatible instantiation
15817 like X<T>, so look up the name in the original template. */
15818 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
15820 /* scope is a partial instantiation, so we can't do the lookup or we
15821 will lose the template arguments. */
15823 /* Enter the SCOPE so that name lookup will be resolved as if we
15824 were in the class definition. In particular, SCOPE will no
15825 longer be considered a dependent type. */
15826 pushed_scope = push_scope (scope);
15827 /* Look up the declaration. */
15828 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
15830 result = NULL_TREE;
15832 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
15833 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
15836 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
15837 && TREE_CODE (decl) == TYPE_DECL)
15839 result = TREE_TYPE (decl);
15840 if (result == error_mark_node)
15841 result = NULL_TREE;
15843 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
15844 && DECL_CLASS_TEMPLATE_P (decl))
15848 /* Obtain the template and the arguments. */
15849 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
15850 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
15851 /* Instantiate the template. */
15852 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
15853 /*entering_scope=*/0,
15854 tf_error | tf_user);
15855 if (result == error_mark_node)
15856 result = NULL_TREE;
15859 /* Leave the SCOPE. */
15861 pop_scope (pushed_scope);
15863 /* If we failed to resolve it, return the original typename. */
15867 /* If lookup found a typename type, resolve that too. */
15868 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
15870 /* Ill-formed programs can cause infinite recursion here, so we
15871 must catch that. */
15872 TYPENAME_IS_RESOLVING_P (type) = 1;
15873 result = resolve_typename_type (result, only_current_p);
15874 TYPENAME_IS_RESOLVING_P (type) = 0;
15877 /* Qualify the resulting type. */
15878 quals = cp_type_quals (type);
15880 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
15885 /* EXPR is an expression which is not type-dependent. Return a proxy
15886 for EXPR that can be used to compute the types of larger
15887 expressions containing EXPR. */
15890 build_non_dependent_expr (tree expr)
15894 /* Preserve null pointer constants so that the type of things like
15895 "p == 0" where "p" is a pointer can be determined. */
15896 if (null_ptr_cst_p (expr))
15898 /* Preserve OVERLOADs; the functions must be available to resolve
15901 if (TREE_CODE (inner_expr) == STMT_EXPR)
15902 inner_expr = stmt_expr_value_expr (inner_expr);
15903 if (TREE_CODE (inner_expr) == ADDR_EXPR)
15904 inner_expr = TREE_OPERAND (inner_expr, 0);
15905 if (TREE_CODE (inner_expr) == COMPONENT_REF)
15906 inner_expr = TREE_OPERAND (inner_expr, 1);
15907 if (is_overloaded_fn (inner_expr)
15908 || TREE_CODE (inner_expr) == OFFSET_REF)
15910 /* There is no need to return a proxy for a variable. */
15911 if (TREE_CODE (expr) == VAR_DECL)
15913 /* Preserve string constants; conversions from string constants to
15914 "char *" are allowed, even though normally a "const char *"
15915 cannot be used to initialize a "char *". */
15916 if (TREE_CODE (expr) == STRING_CST)
15918 /* Preserve arithmetic constants, as an optimization -- there is no
15919 reason to create a new node. */
15920 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
15922 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
15923 There is at least one place where we want to know that a
15924 particular expression is a throw-expression: when checking a ?:
15925 expression, there are special rules if the second or third
15926 argument is a throw-expression. */
15927 if (TREE_CODE (expr) == THROW_EXPR)
15930 if (TREE_CODE (expr) == COND_EXPR)
15931 return build3 (COND_EXPR,
15933 TREE_OPERAND (expr, 0),
15934 (TREE_OPERAND (expr, 1)
15935 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
15936 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
15937 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
15938 if (TREE_CODE (expr) == COMPOUND_EXPR
15939 && !COMPOUND_EXPR_OVERLOADED (expr))
15940 return build2 (COMPOUND_EXPR,
15942 TREE_OPERAND (expr, 0),
15943 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
15945 /* If the type is unknown, it can't really be non-dependent */
15946 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
15948 /* Otherwise, build a NON_DEPENDENT_EXPR.
15950 REFERENCE_TYPEs are not stripped for expressions in templates
15951 because doing so would play havoc with mangling. Consider, for
15954 template <typename T> void f<T& g>() { g(); }
15956 In the body of "f", the expression for "g" will have
15957 REFERENCE_TYPE, even though the standard says that it should
15958 not. The reason is that we must preserve the syntactic form of
15959 the expression so that mangling (say) "f<g>" inside the body of
15960 "f" works out correctly. Therefore, the REFERENCE_TYPE is
15962 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
15965 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
15966 Return a new TREE_LIST with the various arguments replaced with
15967 equivalent non-dependent expressions. */
15970 build_non_dependent_args (tree args)
15975 new_args = NULL_TREE;
15976 for (a = args; a; a = TREE_CHAIN (a))
15977 new_args = tree_cons (NULL_TREE,
15978 build_non_dependent_expr (TREE_VALUE (a)),
15980 return nreverse (new_args);
15983 #include "gt-cp-pt.h"