1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009
4 Free Software Foundation, Inc.
5 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
6 Rewritten by Jason Merrill (jason@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
39 #include "cp-objcp-common.h"
40 #include "tree-inline.h"
47 #include "tree-iterator.h"
50 /* The type of functions taking a tree, and some additional data, and
52 typedef int (*tree_fn_t) (tree, void*);
54 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
55 instantiations have been deferred, either because their definitions
56 were not yet available, or because we were putting off doing the work. */
57 struct GTY (()) pending_template {
58 struct pending_template *next;
59 struct tinst_level *tinst;
62 static GTY(()) struct pending_template *pending_templates;
63 static GTY(()) struct pending_template *last_pending_template;
65 int processing_template_parmlist;
66 static int template_header_count;
68 static GTY(()) tree saved_trees;
69 static VEC(int,heap) *inline_parm_levels;
71 static GTY(()) struct tinst_level *current_tinst_level;
73 static GTY(()) tree saved_access_scope;
75 /* Live only within one (recursive) call to tsubst_expr. We use
76 this to pass the statement expression node from the STMT_EXPR
77 to the EXPR_STMT that is its result. */
78 static tree cur_stmt_expr;
80 /* A map from local variable declarations in the body of the template
81 presently being instantiated to the corresponding instantiated
83 static htab_t local_specializations;
85 typedef struct GTY(()) spec_entry
92 static GTY ((param_is (spec_entry)))
93 htab_t decl_specializations;
95 static GTY ((param_is (spec_entry)))
96 htab_t type_specializations;
98 /* Contains canonical template parameter types. The vector is indexed by
99 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
100 TREE_LIST, whose TREE_VALUEs contain the canonical template
101 parameters of various types and levels. */
102 static GTY(()) VEC(tree,gc) *canonical_template_parms;
104 #define UNIFY_ALLOW_NONE 0
105 #define UNIFY_ALLOW_MORE_CV_QUAL 1
106 #define UNIFY_ALLOW_LESS_CV_QUAL 2
107 #define UNIFY_ALLOW_DERIVED 4
108 #define UNIFY_ALLOW_INTEGER 8
109 #define UNIFY_ALLOW_OUTER_LEVEL 16
110 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
111 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
113 static void push_access_scope (tree);
114 static void pop_access_scope (tree);
115 static bool resolve_overloaded_unification (tree, tree, tree, tree,
116 unification_kind_t, int);
117 static int try_one_overload (tree, tree, tree, tree, tree,
118 unification_kind_t, int, bool);
119 static int unify (tree, tree, tree, tree, int);
120 static void add_pending_template (tree);
121 static int push_tinst_level (tree);
122 static void pop_tinst_level (void);
123 static tree reopen_tinst_level (struct tinst_level *);
124 static tree tsubst_initializer_list (tree, tree);
125 static tree get_class_bindings (tree, tree, tree);
126 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
128 static void tsubst_enum (tree, tree, tree);
129 static tree add_to_template_args (tree, tree);
130 static tree add_outermost_template_args (tree, tree);
131 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
132 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
134 static int type_unification_real (tree, tree, tree, const tree *,
135 unsigned int, int, unification_kind_t, int);
136 static void note_template_header (int);
137 static tree convert_nontype_argument_function (tree, tree);
138 static tree convert_nontype_argument (tree, tree);
139 static tree convert_template_argument (tree, tree, tree,
140 tsubst_flags_t, int, tree);
141 static int for_each_template_parm (tree, tree_fn_t, void*,
142 struct pointer_set_t*, bool);
143 static tree expand_template_argument_pack (tree);
144 static tree build_template_parm_index (int, int, int, tree, tree);
145 static bool inline_needs_template_parms (tree);
146 static void push_inline_template_parms_recursive (tree, int);
147 static tree retrieve_local_specialization (tree);
148 static void register_local_specialization (tree, tree);
149 static hashval_t hash_specialization (const void *p);
150 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
151 static int mark_template_parm (tree, void *);
152 static int template_parm_this_level_p (tree, void *);
153 static tree tsubst_friend_function (tree, tree);
154 static tree tsubst_friend_class (tree, tree);
155 static int can_complete_type_without_circularity (tree);
156 static tree get_bindings (tree, tree, tree, bool);
157 static int template_decl_level (tree);
158 static int check_cv_quals_for_unify (int, tree, tree);
159 static void template_parm_level_and_index (tree, int*, int*);
160 static int unify_pack_expansion (tree, tree, tree, tree, int, bool, bool);
161 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
162 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
163 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
164 static void regenerate_decl_from_template (tree, tree);
165 static tree most_specialized_class (tree, tree);
166 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
167 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
168 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
169 static bool check_specialization_scope (void);
170 static tree process_partial_specialization (tree);
171 static void set_current_access_from_decl (tree);
172 static tree get_template_base (tree, tree, tree, tree);
173 static tree try_class_unification (tree, tree, tree, tree);
174 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
176 static bool template_template_parm_bindings_ok_p (tree, tree);
177 static int template_args_equal (tree, tree);
178 static void tsubst_default_arguments (tree);
179 static tree for_each_template_parm_r (tree *, int *, void *);
180 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
181 static void copy_default_args_to_explicit_spec (tree);
182 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
183 static int eq_local_specializations (const void *, const void *);
184 static bool dependent_template_arg_p (tree);
185 static bool any_template_arguments_need_structural_equality_p (tree);
186 static bool dependent_type_p_r (tree);
187 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
188 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
189 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
190 static tree tsubst_decl (tree, tree, tsubst_flags_t);
191 static void perform_typedefs_access_check (tree tmpl, tree targs);
192 static void append_type_to_template_for_access_check_1 (tree, tree, tree);
193 static hashval_t iterative_hash_template_arg (tree arg, hashval_t val);
194 static bool primary_template_instantiation_p (const_tree);
195 static tree listify (tree);
196 static tree listify_autos (tree, tree);
198 /* Make the current scope suitable for access checking when we are
199 processing T. T can be FUNCTION_DECL for instantiated function
200 template, or VAR_DECL for static member variable (need by
201 instantiate_decl). */
204 push_access_scope (tree t)
206 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
207 || TREE_CODE (t) == VAR_DECL);
209 if (DECL_FRIEND_CONTEXT (t))
210 push_nested_class (DECL_FRIEND_CONTEXT (t));
211 else if (DECL_CLASS_SCOPE_P (t))
212 push_nested_class (DECL_CONTEXT (t));
214 push_to_top_level ();
216 if (TREE_CODE (t) == FUNCTION_DECL)
218 saved_access_scope = tree_cons
219 (NULL_TREE, current_function_decl, saved_access_scope);
220 current_function_decl = t;
224 /* Restore the scope set up by push_access_scope. T is the node we
228 pop_access_scope (tree t)
230 if (TREE_CODE (t) == FUNCTION_DECL)
232 current_function_decl = TREE_VALUE (saved_access_scope);
233 saved_access_scope = TREE_CHAIN (saved_access_scope);
236 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
239 pop_from_top_level ();
242 /* Do any processing required when DECL (a member template
243 declaration) is finished. Returns the TEMPLATE_DECL corresponding
244 to DECL, unless it is a specialization, in which case the DECL
245 itself is returned. */
248 finish_member_template_decl (tree decl)
250 if (decl == error_mark_node)
251 return error_mark_node;
253 gcc_assert (DECL_P (decl));
255 if (TREE_CODE (decl) == TYPE_DECL)
259 type = TREE_TYPE (decl);
260 if (type == error_mark_node)
261 return error_mark_node;
262 if (MAYBE_CLASS_TYPE_P (type)
263 && CLASSTYPE_TEMPLATE_INFO (type)
264 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
266 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
267 check_member_template (tmpl);
272 else if (TREE_CODE (decl) == FIELD_DECL)
273 error ("data member %qD cannot be a member template", decl);
274 else if (DECL_TEMPLATE_INFO (decl))
276 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
278 check_member_template (DECL_TI_TEMPLATE (decl));
279 return DECL_TI_TEMPLATE (decl);
285 error ("invalid member template declaration %qD", decl);
287 return error_mark_node;
290 /* Return the template info node corresponding to T, whatever T is. */
293 get_template_info (const_tree t)
295 tree tinfo = NULL_TREE;
297 if (!t || t == error_mark_node)
300 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
301 tinfo = DECL_TEMPLATE_INFO (t);
303 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
306 if (TAGGED_TYPE_P (t))
307 tinfo = TYPE_TEMPLATE_INFO (t);
312 /* Returns the template nesting level of the indicated class TYPE.
322 A<T>::B<U> has depth two, while A<T> has depth one.
323 Both A<T>::B<int> and A<int>::B<U> have depth one, if
324 they are instantiations, not specializations.
326 This function is guaranteed to return 0 if passed NULL_TREE so
327 that, for example, `template_class_depth (current_class_type)' is
331 template_class_depth (tree type)
336 type && TREE_CODE (type) != NAMESPACE_DECL;
337 type = (TREE_CODE (type) == FUNCTION_DECL)
338 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
340 tree tinfo = get_template_info (type);
342 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
343 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
350 /* Subroutine of maybe_begin_member_template_processing.
351 Returns true if processing DECL needs us to push template parms. */
354 inline_needs_template_parms (tree decl)
356 if (! DECL_TEMPLATE_INFO (decl))
359 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
360 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
363 /* Subroutine of maybe_begin_member_template_processing.
364 Push the template parms in PARMS, starting from LEVELS steps into the
365 chain, and ending at the beginning, since template parms are listed
369 push_inline_template_parms_recursive (tree parmlist, int levels)
371 tree parms = TREE_VALUE (parmlist);
375 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
377 ++processing_template_decl;
378 current_template_parms
379 = tree_cons (size_int (processing_template_decl),
380 parms, current_template_parms);
381 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
383 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
385 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
387 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
389 if (parm == error_mark_node)
392 gcc_assert (DECL_P (parm));
394 switch (TREE_CODE (parm))
403 /* Make a CONST_DECL as is done in process_template_parm.
404 It is ugly that we recreate this here; the original
405 version built in process_template_parm is no longer
407 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
408 CONST_DECL, DECL_NAME (parm),
410 DECL_ARTIFICIAL (decl) = 1;
411 TREE_CONSTANT (decl) = 1;
412 TREE_READONLY (decl) = 1;
413 DECL_INITIAL (decl) = DECL_INITIAL (parm);
414 SET_DECL_TEMPLATE_PARM_P (decl);
425 /* Restore the template parameter context for a member template or
426 a friend template defined in a class definition. */
429 maybe_begin_member_template_processing (tree decl)
434 if (inline_needs_template_parms (decl))
436 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
437 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
439 if (DECL_TEMPLATE_SPECIALIZATION (decl))
442 parms = TREE_CHAIN (parms);
445 push_inline_template_parms_recursive (parms, levels);
448 /* Remember how many levels of template parameters we pushed so that
449 we can pop them later. */
450 VEC_safe_push (int, heap, inline_parm_levels, levels);
453 /* Undo the effects of maybe_begin_member_template_processing. */
456 maybe_end_member_template_processing (void)
461 if (VEC_length (int, inline_parm_levels) == 0)
464 last = VEC_pop (int, inline_parm_levels);
465 for (i = 0; i < last; ++i)
467 --processing_template_decl;
468 current_template_parms = TREE_CHAIN (current_template_parms);
473 /* Return a new template argument vector which contains all of ARGS,
474 but has as its innermost set of arguments the EXTRA_ARGS. */
477 add_to_template_args (tree args, tree extra_args)
484 extra_depth = TMPL_ARGS_DEPTH (extra_args);
485 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
487 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
488 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
490 for (j = 1; j <= extra_depth; ++j, ++i)
491 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
496 /* Like add_to_template_args, but only the outermost ARGS are added to
497 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
498 (EXTRA_ARGS) levels are added. This function is used to combine
499 the template arguments from a partial instantiation with the
500 template arguments used to attain the full instantiation from the
501 partial instantiation. */
504 add_outermost_template_args (tree args, tree extra_args)
508 /* If there are more levels of EXTRA_ARGS than there are ARGS,
509 something very fishy is going on. */
510 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
512 /* If *all* the new arguments will be the EXTRA_ARGS, just return
514 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
517 /* For the moment, we make ARGS look like it contains fewer levels. */
518 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
520 new_args = add_to_template_args (args, extra_args);
522 /* Now, we restore ARGS to its full dimensions. */
523 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
528 /* Return the N levels of innermost template arguments from the ARGS. */
531 get_innermost_template_args (tree args, int n)
539 /* If N is 1, just return the innermost set of template arguments. */
541 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
543 /* If we're not removing anything, just return the arguments we were
545 extra_levels = TMPL_ARGS_DEPTH (args) - n;
546 gcc_assert (extra_levels >= 0);
547 if (extra_levels == 0)
550 /* Make a new set of arguments, not containing the outer arguments. */
551 new_args = make_tree_vec (n);
552 for (i = 1; i <= n; ++i)
553 SET_TMPL_ARGS_LEVEL (new_args, i,
554 TMPL_ARGS_LEVEL (args, i + extra_levels));
559 /* The inverse of get_innermost_template_args: Return all but the innermost
560 EXTRA_LEVELS levels of template arguments from the ARGS. */
563 strip_innermost_template_args (tree args, int extra_levels)
566 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
571 /* If N is 1, just return the outermost set of template arguments. */
573 return TMPL_ARGS_LEVEL (args, 1);
575 /* If we're not removing anything, just return the arguments we were
577 gcc_assert (extra_levels >= 0);
578 if (extra_levels == 0)
581 /* Make a new set of arguments, not containing the inner arguments. */
582 new_args = make_tree_vec (n);
583 for (i = 1; i <= n; ++i)
584 SET_TMPL_ARGS_LEVEL (new_args, i,
585 TMPL_ARGS_LEVEL (args, i));
590 /* We've got a template header coming up; push to a new level for storing
594 begin_template_parm_list (void)
596 /* We use a non-tag-transparent scope here, which causes pushtag to
597 put tags in this scope, rather than in the enclosing class or
598 namespace scope. This is the right thing, since we want
599 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
600 global template class, push_template_decl handles putting the
601 TEMPLATE_DECL into top-level scope. For a nested template class,
604 template <class T> struct S1 {
605 template <class T> struct S2 {};
608 pushtag contains special code to call pushdecl_with_scope on the
609 TEMPLATE_DECL for S2. */
610 begin_scope (sk_template_parms, NULL);
611 ++processing_template_decl;
612 ++processing_template_parmlist;
613 note_template_header (0);
616 /* This routine is called when a specialization is declared. If it is
617 invalid to declare a specialization here, an error is reported and
618 false is returned, otherwise this routine will return true. */
621 check_specialization_scope (void)
623 tree scope = current_scope ();
627 An explicit specialization shall be declared in the namespace of
628 which the template is a member, or, for member templates, in the
629 namespace of which the enclosing class or enclosing class
630 template is a member. An explicit specialization of a member
631 function, member class or static data member of a class template
632 shall be declared in the namespace of which the class template
634 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
636 error ("explicit specialization in non-namespace scope %qD", scope);
642 In an explicit specialization declaration for a member of a class
643 template or a member template that appears in namespace scope,
644 the member template and some of its enclosing class templates may
645 remain unspecialized, except that the declaration shall not
646 explicitly specialize a class member template if its enclosing
647 class templates are not explicitly specialized as well. */
648 if (current_template_parms)
650 error ("enclosing class templates are not explicitly specialized");
657 /* We've just seen template <>. */
660 begin_specialization (void)
662 begin_scope (sk_template_spec, NULL);
663 note_template_header (1);
664 return check_specialization_scope ();
667 /* Called at then end of processing a declaration preceded by
671 end_specialization (void)
674 reset_specialization ();
677 /* Any template <>'s that we have seen thus far are not referring to a
678 function specialization. */
681 reset_specialization (void)
683 processing_specialization = 0;
684 template_header_count = 0;
687 /* We've just seen a template header. If SPECIALIZATION is nonzero,
688 it was of the form template <>. */
691 note_template_header (int specialization)
693 processing_specialization = specialization;
694 template_header_count++;
697 /* We're beginning an explicit instantiation. */
700 begin_explicit_instantiation (void)
702 gcc_assert (!processing_explicit_instantiation);
703 processing_explicit_instantiation = true;
708 end_explicit_instantiation (void)
710 gcc_assert (processing_explicit_instantiation);
711 processing_explicit_instantiation = false;
714 /* An explicit specialization or partial specialization TMPL is being
715 declared. Check that the namespace in which the specialization is
716 occurring is permissible. Returns false iff it is invalid to
717 specialize TMPL in the current namespace. */
720 check_specialization_namespace (tree tmpl)
722 tree tpl_ns = decl_namespace_context (tmpl);
726 An explicit specialization shall be declared in the namespace of
727 which the template is a member, or, for member templates, in the
728 namespace of which the enclosing class or enclosing class
729 template is a member. An explicit specialization of a member
730 function, member class or static data member of a class template
731 shall be declared in the namespace of which the class template is
733 if (is_associated_namespace (current_namespace, tpl_ns))
734 /* Same or super-using namespace. */
738 permerror (input_location, "specialization of %qD in different namespace", tmpl);
739 permerror (input_location, " from definition of %q+#D", tmpl);
744 /* SPEC is an explicit instantiation. Check that it is valid to
745 perform this explicit instantiation in the current namespace. */
748 check_explicit_instantiation_namespace (tree spec)
752 /* DR 275: An explicit instantiation shall appear in an enclosing
753 namespace of its template. */
754 ns = decl_namespace_context (spec);
755 if (!is_ancestor (current_namespace, ns))
756 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
757 "(which does not enclose namespace %qD)",
758 spec, current_namespace, ns);
761 /* The TYPE is being declared. If it is a template type, that means it
762 is a partial specialization. Do appropriate error-checking. */
765 maybe_process_partial_specialization (tree type)
769 if (type == error_mark_node)
770 return error_mark_node;
772 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
774 error ("name of class shadows template template parameter %qD",
776 return error_mark_node;
779 context = TYPE_CONTEXT (type);
781 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
783 /* This is for ordinary explicit specialization and partial
784 specialization of a template class such as:
786 template <> class C<int>;
790 template <class T> class C<T*>;
792 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
794 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
795 && !COMPLETE_TYPE_P (type))
797 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
798 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
799 if (processing_template_decl)
801 if (push_template_decl (TYPE_MAIN_DECL (type))
803 return error_mark_node;
806 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
807 error ("specialization of %qT after instantiation", type);
809 else if (CLASS_TYPE_P (type)
810 && !CLASSTYPE_USE_TEMPLATE (type)
811 && CLASSTYPE_TEMPLATE_INFO (type)
812 && context && CLASS_TYPE_P (context)
813 && CLASSTYPE_TEMPLATE_INFO (context))
815 /* This is for an explicit specialization of member class
816 template according to [temp.expl.spec/18]:
818 template <> template <class U> class C<int>::D;
820 The context `C<int>' must be an implicit instantiation.
821 Otherwise this is just a member class template declared
824 template <> class C<int> { template <class U> class D; };
825 template <> template <class U> class C<int>::D;
827 In the first case, `C<int>::D' is a specialization of `C<T>::D'
828 while in the second case, `C<int>::D' is a primary template
829 and `C<T>::D' may not exist. */
831 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
832 && !COMPLETE_TYPE_P (type))
835 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
837 if (current_namespace
838 != decl_namespace_context (tmpl))
840 permerror (input_location, "specializing %q#T in different namespace", type);
841 permerror (input_location, " from definition of %q+#D", tmpl);
844 /* Check for invalid specialization after instantiation:
846 template <> template <> class C<int>::D<int>;
847 template <> template <class U> class C<int>::D; */
849 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
850 t; t = TREE_CHAIN (t))
852 tree inst = TREE_VALUE (t);
853 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
855 /* We already have a full specialization of this partial
856 instantiation. Reassign it to the new member
857 specialization template. */
861 elt.tmpl = most_general_template (tmpl);
862 elt.args = CLASSTYPE_TI_ARGS (inst);
865 htab_remove_elt (type_specializations, &elt);
868 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
870 slot = (spec_entry **)
871 htab_find_slot (type_specializations, &elt, INSERT);
872 *slot = GGC_NEW (spec_entry);
875 else if (COMPLETE_TYPE_P (inst) || TYPE_BEING_DEFINED (inst))
876 /* But if we've had an implicit instantiation, that's a
877 problem ([temp.expl.spec]/6). */
878 error ("specialization %qT after instantiation %qT",
882 /* Mark TYPE as a specialization. And as a result, we only
883 have one level of template argument for the innermost
885 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
886 CLASSTYPE_TI_ARGS (type)
887 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
890 else if (processing_specialization)
892 error ("explicit specialization of non-template %qT", type);
893 return error_mark_node;
899 /* Returns nonzero if we can optimize the retrieval of specializations
900 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
901 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
904 optimize_specialization_lookup_p (tree tmpl)
906 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
907 && DECL_CLASS_SCOPE_P (tmpl)
908 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
910 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
911 /* The optimized lookup depends on the fact that the
912 template arguments for the member function template apply
913 purely to the containing class, which is not true if the
914 containing class is an explicit or partial
916 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
917 && !DECL_MEMBER_TEMPLATE_P (tmpl)
918 && !DECL_CONV_FN_P (tmpl)
919 /* It is possible to have a template that is not a member
920 template and is not a member of a template class:
922 template <typename T>
923 struct S { friend A::f(); };
925 Here, the friend function is a template, but the context does
926 not have template information. The optimized lookup relies
927 on having ARGS be the template arguments for both the class
928 and the function template. */
929 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
932 /* Retrieve the specialization (in the sense of [temp.spec] - a
933 specialization is either an instantiation or an explicit
934 specialization) of TMPL for the given template ARGS. If there is
935 no such specialization, return NULL_TREE. The ARGS are a vector of
936 arguments, or a vector of vectors of arguments, in the case of
937 templates with more than one level of parameters.
939 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
940 then we search for a partial specialization matching ARGS. This
941 parameter is ignored if TMPL is not a class template. */
944 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
946 if (args == error_mark_node)
949 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
951 /* There should be as many levels of arguments as there are
952 levels of parameters. */
953 gcc_assert (TMPL_ARGS_DEPTH (args)
954 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
956 if (optimize_specialization_lookup_p (tmpl))
959 tree class_specialization;
960 VEC(tree,gc) *methods;
964 /* The template arguments actually apply to the containing
965 class. Find the class specialization with those
967 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
969 = retrieve_specialization (class_template, args, 0);
970 if (!class_specialization)
972 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
973 for the specialization. */
974 idx = class_method_index_for_fn (class_specialization, tmpl);
977 /* Iterate through the methods with the indicated name, looking
978 for the one that has an instance of TMPL. */
979 methods = CLASSTYPE_METHOD_VEC (class_specialization);
980 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
982 tree fn = OVL_CURRENT (fns);
983 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
984 /* using-declarations can add base methods to the method vec,
985 and we don't want those here. */
986 && DECL_CONTEXT (fn) == class_specialization)
995 htab_t specializations;
999 elt.spec = NULL_TREE;
1001 if (DECL_CLASS_TEMPLATE_P (tmpl))
1002 specializations = type_specializations;
1004 specializations = decl_specializations;
1007 hash = hash_specialization (&elt);
1008 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1016 /* Like retrieve_specialization, but for local declarations. */
1019 retrieve_local_specialization (tree tmpl)
1023 if (local_specializations == NULL)
1026 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1027 htab_hash_pointer (tmpl));
1028 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1031 /* Returns nonzero iff DECL is a specialization of TMPL. */
1034 is_specialization_of (tree decl, tree tmpl)
1038 if (TREE_CODE (decl) == FUNCTION_DECL)
1042 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1048 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1050 for (t = TREE_TYPE (decl);
1052 t = CLASSTYPE_USE_TEMPLATE (t)
1053 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1054 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1061 /* Returns nonzero iff DECL is a specialization of friend declaration
1062 FRIEND_DECL according to [temp.friend]. */
1065 is_specialization_of_friend (tree decl, tree friend_decl)
1067 bool need_template = true;
1070 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1071 || TREE_CODE (decl) == TYPE_DECL);
1073 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1074 of a template class, we want to check if DECL is a specialization
1076 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1077 && DECL_TEMPLATE_INFO (friend_decl)
1078 && !DECL_USE_TEMPLATE (friend_decl))
1080 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1081 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1082 need_template = false;
1084 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1085 && !PRIMARY_TEMPLATE_P (friend_decl))
1086 need_template = false;
1088 /* There is nothing to do if this is not a template friend. */
1089 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1092 if (is_specialization_of (decl, friend_decl))
1096 A member of a class template may be declared to be a friend of a
1097 non-template class. In this case, the corresponding member of
1098 every specialization of the class template is a friend of the
1099 class granting friendship.
1101 For example, given a template friend declaration
1103 template <class T> friend void A<T>::f();
1105 the member function below is considered a friend
1107 template <> struct A<int> {
1111 For this type of template friend, TEMPLATE_DEPTH below will be
1112 nonzero. To determine if DECL is a friend of FRIEND, we first
1113 check if the enclosing class is a specialization of another. */
1115 template_depth = template_class_depth (DECL_CONTEXT (friend_decl));
1117 && DECL_CLASS_SCOPE_P (decl)
1118 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1119 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1121 /* Next, we check the members themselves. In order to handle
1122 a few tricky cases, such as when FRIEND_DECL's are
1124 template <class T> friend void A<T>::g(T t);
1125 template <class T> template <T t> friend void A<T>::h();
1129 void A<int>::g(int);
1130 template <int> void A<int>::h();
1132 we need to figure out ARGS, the template arguments from
1133 the context of DECL. This is required for template substitution
1134 of `T' in the function parameter of `g' and template parameter
1135 of `h' in the above examples. Here ARGS corresponds to `int'. */
1137 tree context = DECL_CONTEXT (decl);
1138 tree args = NULL_TREE;
1139 int current_depth = 0;
1141 while (current_depth < template_depth)
1143 if (CLASSTYPE_TEMPLATE_INFO (context))
1145 if (current_depth == 0)
1146 args = TYPE_TI_ARGS (context);
1148 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1151 context = TYPE_CONTEXT (context);
1154 if (TREE_CODE (decl) == FUNCTION_DECL)
1159 tree friend_args_type;
1160 tree decl_args_type;
1162 /* Make sure that both DECL and FRIEND_DECL are templates or
1164 is_template = DECL_TEMPLATE_INFO (decl)
1165 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1166 if (need_template ^ is_template)
1168 else if (is_template)
1170 /* If both are templates, check template parameter list. */
1172 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1174 if (!comp_template_parms
1175 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1179 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1182 decl_type = TREE_TYPE (decl);
1184 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1185 tf_none, NULL_TREE);
1186 if (friend_type == error_mark_node)
1189 /* Check if return types match. */
1190 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1193 /* Check if function parameter types match, ignoring the
1194 `this' parameter. */
1195 friend_args_type = TYPE_ARG_TYPES (friend_type);
1196 decl_args_type = TYPE_ARG_TYPES (decl_type);
1197 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1198 friend_args_type = TREE_CHAIN (friend_args_type);
1199 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1200 decl_args_type = TREE_CHAIN (decl_args_type);
1202 return compparms (decl_args_type, friend_args_type);
1206 /* DECL is a TYPE_DECL */
1208 tree decl_type = TREE_TYPE (decl);
1210 /* Make sure that both DECL and FRIEND_DECL are templates or
1213 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1214 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1216 if (need_template ^ is_template)
1218 else if (is_template)
1221 /* If both are templates, check the name of the two
1222 TEMPLATE_DECL's first because is_friend didn't. */
1223 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1224 != DECL_NAME (friend_decl))
1227 /* Now check template parameter list. */
1229 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1231 return comp_template_parms
1232 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1236 return (DECL_NAME (decl)
1237 == DECL_NAME (friend_decl));
1243 /* Register the specialization SPEC as a specialization of TMPL with
1244 the indicated ARGS. IS_FRIEND indicates whether the specialization
1245 is actually just a friend declaration. Returns SPEC, or an
1246 equivalent prior declaration, if available. */
1249 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1253 spec_entry **slot = NULL;
1256 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1258 if (TREE_CODE (spec) == FUNCTION_DECL
1259 && uses_template_parms (DECL_TI_ARGS (spec)))
1260 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1261 register it; we want the corresponding TEMPLATE_DECL instead.
1262 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1263 the more obvious `uses_template_parms (spec)' to avoid problems
1264 with default function arguments. In particular, given
1265 something like this:
1267 template <class T> void f(T t1, T t = T())
1269 the default argument expression is not substituted for in an
1270 instantiation unless and until it is actually needed. */
1273 if (optimize_specialization_lookup_p (tmpl))
1274 /* We don't put these specializations in the hash table, but we might
1275 want to give an error about a mismatch. */
1276 fn = retrieve_specialization (tmpl, args, 0);
1284 hash = hash_specialization (&elt);
1286 slot = (spec_entry **)
1287 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1294 /* We can sometimes try to re-register a specialization that we've
1295 already got. In particular, regenerate_decl_from_template calls
1296 duplicate_decls which will update the specialization list. But,
1297 we'll still get called again here anyhow. It's more convenient
1298 to simply allow this than to try to prevent it. */
1301 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1303 if (DECL_TEMPLATE_INSTANTIATION (fn))
1305 if (DECL_ODR_USED (fn)
1306 || DECL_EXPLICIT_INSTANTIATION (fn))
1308 error ("specialization of %qD after instantiation",
1310 return error_mark_node;
1315 /* This situation should occur only if the first
1316 specialization is an implicit instantiation, the
1317 second is an explicit specialization, and the
1318 implicit instantiation has not yet been used. That
1319 situation can occur if we have implicitly
1320 instantiated a member function and then specialized
1323 We can also wind up here if a friend declaration that
1324 looked like an instantiation turns out to be a
1327 template <class T> void foo(T);
1328 class S { friend void foo<>(int) };
1329 template <> void foo(int);
1331 We transform the existing DECL in place so that any
1332 pointers to it become pointers to the updated
1335 If there was a definition for the template, but not
1336 for the specialization, we want this to look as if
1337 there were no definition, and vice versa. */
1338 DECL_INITIAL (fn) = NULL_TREE;
1339 duplicate_decls (spec, fn, is_friend);
1340 /* The call to duplicate_decls will have applied
1343 An explicit specialization of a function template
1344 is inline only if it is explicitly declared to be,
1345 and independently of whether its function template
1348 to the primary function; now copy the inline bits to
1349 the various clones. */
1350 FOR_EACH_CLONE (clone, fn)
1352 DECL_DECLARED_INLINE_P (clone)
1353 = DECL_DECLARED_INLINE_P (fn);
1354 DECL_SOURCE_LOCATION (clone)
1355 = DECL_SOURCE_LOCATION (fn);
1357 check_specialization_namespace (fn);
1362 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1364 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1365 /* Dup decl failed, but this is a new definition. Set the
1366 line number so any errors match this new
1368 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1374 return duplicate_decls (spec, fn, is_friend);
1376 /* A specialization must be declared in the same namespace as the
1377 template it is specializing. */
1378 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1379 && !check_specialization_namespace (tmpl))
1380 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1382 if (!optimize_specialization_lookup_p (tmpl))
1384 gcc_assert (tmpl && args && spec);
1385 *slot = GGC_NEW (spec_entry);
1387 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1388 && PRIMARY_TEMPLATE_P (tmpl)
1389 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1390 /* TMPL is a forward declaration of a template function; keep a list
1391 of all specializations in case we need to reassign them to a friend
1392 template later in tsubst_friend_function. */
1393 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1394 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1400 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1401 TMPL and ARGS members, ignores SPEC. */
1404 eq_specializations (const void *p1, const void *p2)
1406 const spec_entry *e1 = (const spec_entry *)p1;
1407 const spec_entry *e2 = (const spec_entry *)p2;
1409 return (e1->tmpl == e2->tmpl
1410 && comp_template_args (e1->args, e2->args));
1413 /* Returns a hash for a template TMPL and template arguments ARGS. */
1416 hash_tmpl_and_args (tree tmpl, tree args)
1418 hashval_t val = DECL_UID (tmpl);
1419 return iterative_hash_template_arg (args, val);
1422 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1426 hash_specialization (const void *p)
1428 const spec_entry *e = (const spec_entry *)p;
1429 return hash_tmpl_and_args (e->tmpl, e->args);
1432 /* Recursively calculate a hash value for a template argument ARG, for use
1433 in the hash tables of template specializations. */
1436 iterative_hash_template_arg (tree arg, hashval_t val)
1438 unsigned HOST_WIDE_INT i;
1439 enum tree_code code;
1442 if (arg == NULL_TREE)
1443 return iterative_hash_object (arg, val);
1448 code = TREE_CODE (arg);
1449 tclass = TREE_CODE_CLASS (code);
1451 val = iterative_hash_object (code, val);
1458 case IDENTIFIER_NODE:
1459 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1463 int i, len = TREE_VEC_LENGTH (arg);
1464 for (i = 0; i < len; ++i)
1465 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1469 case TYPE_PACK_EXPANSION:
1470 case EXPR_PACK_EXPANSION:
1471 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1473 case ARGUMENT_PACK_SELECT:
1474 /* We can get one of these when re-hashing a previous entry in the middle
1475 of substituting into a pack expansion. Just look through it... */
1476 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1477 /* ...and fall through. */
1478 case TYPE_ARGUMENT_PACK:
1479 case NONTYPE_ARGUMENT_PACK:
1480 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1483 for (; arg; arg = TREE_CHAIN (arg))
1484 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1488 for (; arg; arg = OVL_CHAIN (arg))
1489 val = iterative_hash_template_arg (OVL_FUNCTION (arg), val);
1495 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1497 val = iterative_hash_template_arg (field, val);
1498 val = iterative_hash_template_arg (value, val);
1504 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1505 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1508 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1511 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1512 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1514 case TEMPLATE_PARM_INDEX:
1515 val = iterative_hash_template_arg
1516 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1517 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1518 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1521 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1522 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1523 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1526 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1528 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1532 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1533 code = TREE_CODE (TREE_OPERAND (arg, 1));
1534 val = iterative_hash_object (code, val);
1535 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1541 if (TYPE_CANONICAL (arg))
1542 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1544 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1545 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1546 /* Otherwise just compare the types during lookup. */
1549 case tcc_declaration:
1551 return iterative_hash_expr (arg, val);
1554 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1556 unsigned n = TREE_OPERAND_LENGTH (arg);
1557 for (i = 0; i < n; ++i)
1558 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1567 /* Unregister the specialization SPEC as a specialization of TMPL.
1568 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1569 if the SPEC was listed as a specialization of TMPL.
1571 Note that SPEC has been ggc_freed, so we can't look inside it. */
1574 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1579 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1580 elt.args = TI_ARGS (tinfo);
1581 elt.spec = NULL_TREE;
1583 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1586 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1587 gcc_assert (new_spec != NULL_TREE);
1588 (*slot)->spec = new_spec;
1595 /* Compare an entry in the local specializations hash table P1 (which
1596 is really a pointer to a TREE_LIST) with P2 (which is really a
1600 eq_local_specializations (const void *p1, const void *p2)
1602 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1605 /* Hash P1, an entry in the local specializations table. */
1608 hash_local_specialization (const void* p1)
1610 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1613 /* Like register_specialization, but for local declarations. We are
1614 registering SPEC, an instantiation of TMPL. */
1617 register_local_specialization (tree spec, tree tmpl)
1621 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1622 htab_hash_pointer (tmpl), INSERT);
1623 *slot = build_tree_list (spec, tmpl);
1626 /* TYPE is a class type. Returns true if TYPE is an explicitly
1627 specialized class. */
1630 explicit_class_specialization_p (tree type)
1632 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1634 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1637 /* Print the list of candidate FNS in an error message. */
1640 print_candidates (tree fns)
1644 const char *str = "candidates are:";
1646 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1650 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1651 error ("%s %+#D", str, OVL_CURRENT (f));
1656 /* Returns the template (one of the functions given by TEMPLATE_ID)
1657 which can be specialized to match the indicated DECL with the
1658 explicit template args given in TEMPLATE_ID. The DECL may be
1659 NULL_TREE if none is available. In that case, the functions in
1660 TEMPLATE_ID are non-members.
1662 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1663 specialization of a member template.
1665 The TEMPLATE_COUNT is the number of references to qualifying
1666 template classes that appeared in the name of the function. See
1667 check_explicit_specialization for a more accurate description.
1669 TSK indicates what kind of template declaration (if any) is being
1670 declared. TSK_TEMPLATE indicates that the declaration given by
1671 DECL, though a FUNCTION_DECL, has template parameters, and is
1672 therefore a template function.
1674 The template args (those explicitly specified and those deduced)
1675 are output in a newly created vector *TARGS_OUT.
1677 If it is impossible to determine the result, an error message is
1678 issued. The error_mark_node is returned to indicate failure. */
1681 determine_specialization (tree template_id,
1684 int need_member_template,
1690 tree explicit_targs;
1691 tree candidates = NULL_TREE;
1692 /* A TREE_LIST of templates of which DECL may be a specialization.
1693 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1694 corresponding TREE_PURPOSE is the set of template arguments that,
1695 when used to instantiate the template, would produce a function
1696 with the signature of DECL. */
1697 tree templates = NULL_TREE;
1699 struct cp_binding_level *b;
1701 *targs_out = NULL_TREE;
1703 if (template_id == error_mark_node || decl == error_mark_node)
1704 return error_mark_node;
1706 fns = TREE_OPERAND (template_id, 0);
1707 explicit_targs = TREE_OPERAND (template_id, 1);
1709 if (fns == error_mark_node)
1710 return error_mark_node;
1712 /* Check for baselinks. */
1713 if (BASELINK_P (fns))
1714 fns = BASELINK_FUNCTIONS (fns);
1716 if (!is_overloaded_fn (fns))
1718 error ("%qD is not a function template", fns);
1719 return error_mark_node;
1722 /* Count the number of template headers specified for this
1725 for (b = current_binding_level;
1726 b->kind == sk_template_parms;
1730 for (; fns; fns = OVL_NEXT (fns))
1732 tree fn = OVL_CURRENT (fns);
1734 if (TREE_CODE (fn) == TEMPLATE_DECL)
1736 tree decl_arg_types;
1739 /* In case of explicit specialization, we need to check if
1740 the number of template headers appearing in the specialization
1741 is correct. This is usually done in check_explicit_specialization,
1742 but the check done there cannot be exhaustive when specializing
1743 member functions. Consider the following code:
1745 template <> void A<int>::f(int);
1746 template <> template <> void A<int>::f(int);
1748 Assuming that A<int> is not itself an explicit specialization
1749 already, the first line specializes "f" which is a non-template
1750 member function, whilst the second line specializes "f" which
1751 is a template member function. So both lines are syntactically
1752 correct, and check_explicit_specialization does not reject
1755 Here, we can do better, as we are matching the specialization
1756 against the declarations. We count the number of template
1757 headers, and we check if they match TEMPLATE_COUNT + 1
1758 (TEMPLATE_COUNT is the number of qualifying template classes,
1759 plus there must be another header for the member template
1762 Notice that if header_count is zero, this is not a
1763 specialization but rather a template instantiation, so there
1764 is no check we can perform here. */
1765 if (header_count && header_count != template_count + 1)
1768 /* Check that the number of template arguments at the
1769 innermost level for DECL is the same as for FN. */
1770 if (current_binding_level->kind == sk_template_parms
1771 && !current_binding_level->explicit_spec_p
1772 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1773 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1774 (current_template_parms))))
1777 /* DECL might be a specialization of FN. */
1778 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1779 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1781 /* For a non-static member function, we need to make sure
1782 that the const qualification is the same. Since
1783 get_bindings does not try to merge the "this" parameter,
1784 we must do the comparison explicitly. */
1785 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1786 && !same_type_p (TREE_VALUE (fn_arg_types),
1787 TREE_VALUE (decl_arg_types)))
1790 /* Skip the "this" parameter and, for constructors of
1791 classes with virtual bases, the VTT parameter. A
1792 full specialization of a constructor will have a VTT
1793 parameter, but a template never will. */
1795 = skip_artificial_parms_for (decl, decl_arg_types);
1797 = skip_artificial_parms_for (fn, fn_arg_types);
1799 /* Check that the number of function parameters matches.
1801 template <class T> void f(int i = 0);
1802 template <> void f<int>();
1803 The specialization f<int> is invalid but is not caught
1804 by get_bindings below. */
1805 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1808 /* Function templates cannot be specializations; there are
1809 no partial specializations of functions. Therefore, if
1810 the type of DECL does not match FN, there is no
1812 if (tsk == tsk_template)
1814 if (compparms (fn_arg_types, decl_arg_types))
1815 candidates = tree_cons (NULL_TREE, fn, candidates);
1819 /* See whether this function might be a specialization of this
1821 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1824 /* We cannot deduce template arguments that when used to
1825 specialize TMPL will produce DECL. */
1828 /* Save this template, and the arguments deduced. */
1829 templates = tree_cons (targs, fn, templates);
1831 else if (need_member_template)
1832 /* FN is an ordinary member function, and we need a
1833 specialization of a member template. */
1835 else if (TREE_CODE (fn) != FUNCTION_DECL)
1836 /* We can get IDENTIFIER_NODEs here in certain erroneous
1839 else if (!DECL_FUNCTION_MEMBER_P (fn))
1840 /* This is just an ordinary non-member function. Nothing can
1841 be a specialization of that. */
1843 else if (DECL_ARTIFICIAL (fn))
1844 /* Cannot specialize functions that are created implicitly. */
1848 tree decl_arg_types;
1850 /* This is an ordinary member function. However, since
1851 we're here, we can assume it's enclosing class is a
1852 template class. For example,
1854 template <typename T> struct S { void f(); };
1855 template <> void S<int>::f() {}
1857 Here, S<int>::f is a non-template, but S<int> is a
1858 template class. If FN has the same type as DECL, we
1859 might be in business. */
1861 if (!DECL_TEMPLATE_INFO (fn))
1862 /* Its enclosing class is an explicit specialization
1863 of a template class. This is not a candidate. */
1866 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1867 TREE_TYPE (TREE_TYPE (fn))))
1868 /* The return types differ. */
1871 /* Adjust the type of DECL in case FN is a static member. */
1872 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1873 if (DECL_STATIC_FUNCTION_P (fn)
1874 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1875 decl_arg_types = TREE_CHAIN (decl_arg_types);
1877 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1880 candidates = tree_cons (NULL_TREE, fn, candidates);
1884 if (templates && TREE_CHAIN (templates))
1890 It is possible for a specialization with a given function
1891 signature to be instantiated from more than one function
1892 template. In such cases, explicit specification of the
1893 template arguments must be used to uniquely identify the
1894 function template specialization being specialized.
1896 Note that here, there's no suggestion that we're supposed to
1897 determine which of the candidate templates is most
1898 specialized. However, we, also have:
1902 Partial ordering of overloaded function template
1903 declarations is used in the following contexts to select
1904 the function template to which a function template
1905 specialization refers:
1907 -- when an explicit specialization refers to a function
1910 So, we do use the partial ordering rules, at least for now.
1911 This extension can only serve to make invalid programs valid,
1912 so it's safe. And, there is strong anecdotal evidence that
1913 the committee intended the partial ordering rules to apply;
1914 the EDG front end has that behavior, and John Spicer claims
1915 that the committee simply forgot to delete the wording in
1916 [temp.expl.spec]. */
1917 tree tmpl = most_specialized_instantiation (templates);
1918 if (tmpl != error_mark_node)
1921 TREE_CHAIN (templates) = NULL_TREE;
1925 if (templates == NULL_TREE && candidates == NULL_TREE)
1927 error ("template-id %qD for %q+D does not match any template "
1928 "declaration", template_id, decl);
1929 return error_mark_node;
1931 else if ((templates && TREE_CHAIN (templates))
1932 || (candidates && TREE_CHAIN (candidates))
1933 || (templates && candidates))
1935 error ("ambiguous template specialization %qD for %q+D",
1937 chainon (candidates, templates);
1938 print_candidates (candidates);
1939 return error_mark_node;
1942 /* We have one, and exactly one, match. */
1945 tree fn = TREE_VALUE (candidates);
1946 *targs_out = copy_node (DECL_TI_ARGS (fn));
1947 /* DECL is a re-declaration or partial instantiation of a template
1949 if (TREE_CODE (fn) == TEMPLATE_DECL)
1951 /* It was a specialization of an ordinary member function in a
1953 return DECL_TI_TEMPLATE (fn);
1956 /* It was a specialization of a template. */
1957 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1958 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1960 *targs_out = copy_node (targs);
1961 SET_TMPL_ARGS_LEVEL (*targs_out,
1962 TMPL_ARGS_DEPTH (*targs_out),
1963 TREE_PURPOSE (templates));
1966 *targs_out = TREE_PURPOSE (templates);
1967 return TREE_VALUE (templates);
1970 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1971 but with the default argument values filled in from those in the
1975 copy_default_args_to_explicit_spec_1 (tree spec_types,
1978 tree new_spec_types;
1983 if (spec_types == void_list_node)
1984 return void_list_node;
1986 /* Substitute into the rest of the list. */
1988 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1989 TREE_CHAIN (tmpl_types));
1991 /* Add the default argument for this parameter. */
1992 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1993 TREE_VALUE (spec_types),
1997 /* DECL is an explicit specialization. Replicate default arguments
1998 from the template it specializes. (That way, code like:
2000 template <class T> void f(T = 3);
2001 template <> void f(double);
2004 works, as required.) An alternative approach would be to look up
2005 the correct default arguments at the call-site, but this approach
2006 is consistent with how implicit instantiations are handled. */
2009 copy_default_args_to_explicit_spec (tree decl)
2014 tree new_spec_types;
2018 tree object_type = NULL_TREE;
2019 tree in_charge = NULL_TREE;
2020 tree vtt = NULL_TREE;
2022 /* See if there's anything we need to do. */
2023 tmpl = DECL_TI_TEMPLATE (decl);
2024 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2025 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2026 if (TREE_PURPOSE (t))
2031 old_type = TREE_TYPE (decl);
2032 spec_types = TYPE_ARG_TYPES (old_type);
2034 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2036 /* Remove the this pointer, but remember the object's type for
2038 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2039 spec_types = TREE_CHAIN (spec_types);
2040 tmpl_types = TREE_CHAIN (tmpl_types);
2042 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2044 /* DECL may contain more parameters than TMPL due to the extra
2045 in-charge parameter in constructors and destructors. */
2046 in_charge = spec_types;
2047 spec_types = TREE_CHAIN (spec_types);
2049 if (DECL_HAS_VTT_PARM_P (decl))
2052 spec_types = TREE_CHAIN (spec_types);
2056 /* Compute the merged default arguments. */
2058 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2060 /* Compute the new FUNCTION_TYPE. */
2064 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2069 /* Put the in-charge parameter back. */
2070 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2071 TREE_VALUE (in_charge),
2074 new_type = build_method_type_directly (object_type,
2075 TREE_TYPE (old_type),
2079 new_type = build_function_type (TREE_TYPE (old_type),
2081 new_type = cp_build_type_attribute_variant (new_type,
2082 TYPE_ATTRIBUTES (old_type));
2083 new_type = build_exception_variant (new_type,
2084 TYPE_RAISES_EXCEPTIONS (old_type));
2085 TREE_TYPE (decl) = new_type;
2088 /* Check to see if the function just declared, as indicated in
2089 DECLARATOR, and in DECL, is a specialization of a function
2090 template. We may also discover that the declaration is an explicit
2091 instantiation at this point.
2093 Returns DECL, or an equivalent declaration that should be used
2094 instead if all goes well. Issues an error message if something is
2095 amiss. Returns error_mark_node if the error is not easily
2098 FLAGS is a bitmask consisting of the following flags:
2100 2: The function has a definition.
2101 4: The function is a friend.
2103 The TEMPLATE_COUNT is the number of references to qualifying
2104 template classes that appeared in the name of the function. For
2107 template <class T> struct S { void f(); };
2110 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2111 classes are not counted in the TEMPLATE_COUNT, so that in
2113 template <class T> struct S {};
2114 template <> struct S<int> { void f(); }
2115 template <> void S<int>::f();
2117 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2118 invalid; there should be no template <>.)
2120 If the function is a specialization, it is marked as such via
2121 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2122 is set up correctly, and it is added to the list of specializations
2123 for that template. */
2126 check_explicit_specialization (tree declarator,
2131 int have_def = flags & 2;
2132 int is_friend = flags & 4;
2133 int specialization = 0;
2134 int explicit_instantiation = 0;
2135 int member_specialization = 0;
2136 tree ctype = DECL_CLASS_CONTEXT (decl);
2137 tree dname = DECL_NAME (decl);
2142 if (!processing_specialization)
2145 tsk = tsk_excessive_parms;
2148 tsk = current_tmpl_spec_kind (template_count);
2153 if (processing_specialization)
2156 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2158 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2161 /* This could be something like:
2163 template <class T> void f(T);
2164 class S { friend void f<>(int); } */
2168 /* This case handles bogus declarations like template <>
2169 template <class T> void f<int>(); */
2171 error ("template-id %qD in declaration of primary template",
2178 case tsk_invalid_member_spec:
2179 /* The error has already been reported in
2180 check_specialization_scope. */
2181 return error_mark_node;
2183 case tsk_invalid_expl_inst:
2184 error ("template parameter list used in explicit instantiation");
2190 error ("definition provided for explicit instantiation");
2192 explicit_instantiation = 1;
2195 case tsk_excessive_parms:
2196 case tsk_insufficient_parms:
2197 if (tsk == tsk_excessive_parms)
2198 error ("too many template parameter lists in declaration of %qD",
2200 else if (template_header_count)
2201 error("too few template parameter lists in declaration of %qD", decl);
2203 error("explicit specialization of %qD must be introduced by "
2204 "%<template <>%>", decl);
2208 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2210 member_specialization = 1;
2216 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2218 /* This case handles bogus declarations like template <>
2219 template <class T> void f<int>(); */
2221 if (uses_template_parms (declarator))
2222 error ("function template partial specialization %qD "
2223 "is not allowed", declarator);
2225 error ("template-id %qD in declaration of primary template",
2230 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2231 /* This is a specialization of a member template, without
2232 specialization the containing class. Something like:
2234 template <class T> struct S {
2235 template <class U> void f (U);
2237 template <> template <class U> void S<int>::f(U) {}
2239 That's a specialization -- but of the entire template. */
2247 if (specialization || member_specialization)
2249 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2250 for (; t; t = TREE_CHAIN (t))
2251 if (TREE_PURPOSE (t))
2253 permerror (input_location,
2254 "default argument specified in explicit specialization");
2259 if (specialization || member_specialization || explicit_instantiation)
2261 tree tmpl = NULL_TREE;
2262 tree targs = NULL_TREE;
2264 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2265 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2269 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2274 /* If there is no class context, the explicit instantiation
2275 must be at namespace scope. */
2276 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2278 /* Find the namespace binding, using the declaration
2280 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2282 if (fns == error_mark_node || !is_overloaded_fn (fns))
2284 error ("%qD is not a template function", dname);
2285 fns = error_mark_node;
2289 tree fn = OVL_CURRENT (fns);
2290 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2291 CP_DECL_CONTEXT (fn)))
2292 error ("%qD is not declared in %qD",
2293 decl, current_namespace);
2297 declarator = lookup_template_function (fns, NULL_TREE);
2300 if (declarator == error_mark_node)
2301 return error_mark_node;
2303 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2305 if (!explicit_instantiation)
2306 /* A specialization in class scope. This is invalid,
2307 but the error will already have been flagged by
2308 check_specialization_scope. */
2309 return error_mark_node;
2312 /* It's not valid to write an explicit instantiation in
2315 class C { template void f(); }
2317 This case is caught by the parser. However, on
2320 template class C { void f(); };
2322 (which is invalid) we can get here. The error will be
2329 else if (ctype != NULL_TREE
2330 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2333 /* Find the list of functions in ctype that have the same
2334 name as the declared function. */
2335 tree name = TREE_OPERAND (declarator, 0);
2336 tree fns = NULL_TREE;
2339 if (constructor_name_p (name, ctype))
2341 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2343 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2344 : !CLASSTYPE_DESTRUCTORS (ctype))
2346 /* From [temp.expl.spec]:
2348 If such an explicit specialization for the member
2349 of a class template names an implicitly-declared
2350 special member function (clause _special_), the
2351 program is ill-formed.
2353 Similar language is found in [temp.explicit]. */
2354 error ("specialization of implicitly-declared special member function");
2355 return error_mark_node;
2358 name = is_constructor ? ctor_identifier : dtor_identifier;
2361 if (!DECL_CONV_FN_P (decl))
2363 idx = lookup_fnfields_1 (ctype, name);
2365 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2369 VEC(tree,gc) *methods;
2372 /* For a type-conversion operator, we cannot do a
2373 name-based lookup. We might be looking for `operator
2374 int' which will be a specialization of `operator T'.
2375 So, we find *all* the conversion operators, and then
2376 select from them. */
2379 methods = CLASSTYPE_METHOD_VEC (ctype);
2381 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2382 VEC_iterate (tree, methods, idx, ovl);
2385 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2386 /* There are no more conversion functions. */
2389 /* Glue all these conversion functions together
2390 with those we already have. */
2391 for (; ovl; ovl = OVL_NEXT (ovl))
2392 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2396 if (fns == NULL_TREE)
2398 error ("no member function %qD declared in %qT", name, ctype);
2399 return error_mark_node;
2402 TREE_OPERAND (declarator, 0) = fns;
2405 /* Figure out what exactly is being specialized at this point.
2406 Note that for an explicit instantiation, even one for a
2407 member function, we cannot tell apriori whether the
2408 instantiation is for a member template, or just a member
2409 function of a template class. Even if a member template is
2410 being instantiated, the member template arguments may be
2411 elided if they can be deduced from the rest of the
2413 tmpl = determine_specialization (declarator, decl,
2415 member_specialization,
2419 if (!tmpl || tmpl == error_mark_node)
2420 /* We couldn't figure out what this declaration was
2422 return error_mark_node;
2425 tree gen_tmpl = most_general_template (tmpl);
2427 if (explicit_instantiation)
2429 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2430 is done by do_decl_instantiation later. */
2432 int arg_depth = TMPL_ARGS_DEPTH (targs);
2433 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2435 if (arg_depth > parm_depth)
2437 /* If TMPL is not the most general template (for
2438 example, if TMPL is a friend template that is
2439 injected into namespace scope), then there will
2440 be too many levels of TARGS. Remove some of them
2445 new_targs = make_tree_vec (parm_depth);
2446 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2447 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2448 = TREE_VEC_ELT (targs, i);
2452 return instantiate_template (tmpl, targs, tf_error);
2455 /* If we thought that the DECL was a member function, but it
2456 turns out to be specializing a static member function,
2457 make DECL a static member function as well. */
2458 if (DECL_STATIC_FUNCTION_P (tmpl)
2459 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2460 revert_static_member_fn (decl);
2462 /* If this is a specialization of a member template of a
2463 template class, we want to return the TEMPLATE_DECL, not
2464 the specialization of it. */
2465 if (tsk == tsk_template)
2467 tree result = DECL_TEMPLATE_RESULT (tmpl);
2468 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2469 DECL_INITIAL (result) = NULL_TREE;
2473 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2474 DECL_SOURCE_LOCATION (result)
2475 = DECL_SOURCE_LOCATION (decl);
2476 /* We want to use the argument list specified in the
2477 definition, not in the original declaration. */
2478 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2479 for (parm = DECL_ARGUMENTS (result); parm;
2480 parm = TREE_CHAIN (parm))
2481 DECL_CONTEXT (parm) = result;
2483 return register_specialization (tmpl, gen_tmpl, targs,
2487 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2488 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2490 /* Inherit default function arguments from the template
2491 DECL is specializing. */
2492 copy_default_args_to_explicit_spec (decl);
2494 /* This specialization has the same protection as the
2495 template it specializes. */
2496 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2497 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2499 /* 7.1.1-1 [dcl.stc]
2501 A storage-class-specifier shall not be specified in an
2502 explicit specialization...
2504 The parser rejects these, so unless action is taken here,
2505 explicit function specializations will always appear with
2508 The action recommended by the C++ CWG in response to C++
2509 defect report 605 is to make the storage class and linkage
2510 of the explicit specialization match the templated function:
2512 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2514 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2516 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2517 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2519 /* This specialization has the same linkage and visibility as
2520 the function template it specializes. */
2521 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2522 if (! TREE_PUBLIC (decl))
2524 DECL_INTERFACE_KNOWN (decl) = 1;
2525 DECL_NOT_REALLY_EXTERN (decl) = 1;
2527 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2528 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2530 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2531 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2535 /* If DECL is a friend declaration, declared using an
2536 unqualified name, the namespace associated with DECL may
2537 have been set incorrectly. For example, in:
2539 template <typename T> void f(T);
2541 struct S { friend void f<int>(int); }
2544 we will have set the DECL_CONTEXT for the friend
2545 declaration to N, rather than to the global namespace. */
2546 if (DECL_NAMESPACE_SCOPE_P (decl))
2547 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2549 if (is_friend && !have_def)
2550 /* This is not really a declaration of a specialization.
2551 It's just the name of an instantiation. But, it's not
2552 a request for an instantiation, either. */
2553 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2554 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2555 /* This is indeed a specialization. In case of constructors
2556 and destructors, we need in-charge and not-in-charge
2557 versions in V3 ABI. */
2558 clone_function_decl (decl, /*update_method_vec_p=*/0);
2560 /* Register this specialization so that we can find it
2562 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2569 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2570 parameters. These are represented in the same format used for
2571 DECL_TEMPLATE_PARMS. */
2574 comp_template_parms (const_tree parms1, const_tree parms2)
2579 if (parms1 == parms2)
2582 for (p1 = parms1, p2 = parms2;
2583 p1 != NULL_TREE && p2 != NULL_TREE;
2584 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2586 tree t1 = TREE_VALUE (p1);
2587 tree t2 = TREE_VALUE (p2);
2590 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2591 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2593 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2596 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2598 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2599 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2601 /* If either of the template parameters are invalid, assume
2602 they match for the sake of error recovery. */
2603 if (parm1 == error_mark_node || parm2 == error_mark_node)
2606 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2609 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2610 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2611 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2613 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2618 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2619 /* One set of parameters has more parameters lists than the
2626 /* Determine whether PARM is a parameter pack. */
2629 template_parameter_pack_p (const_tree parm)
2631 /* Determine if we have a non-type template parameter pack. */
2632 if (TREE_CODE (parm) == PARM_DECL)
2633 return (DECL_TEMPLATE_PARM_P (parm)
2634 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2636 /* If this is a list of template parameters, we could get a
2637 TYPE_DECL or a TEMPLATE_DECL. */
2638 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2639 parm = TREE_TYPE (parm);
2641 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2642 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2643 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2646 /* Determine if T is a function parameter pack. */
2649 function_parameter_pack_p (const_tree t)
2651 if (t && TREE_CODE (t) == PARM_DECL)
2652 return FUNCTION_PARAMETER_PACK_P (t);
2656 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2657 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2660 get_function_template_decl (const_tree primary_func_tmpl_inst)
2662 if (! primary_func_tmpl_inst
2663 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2664 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2667 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2670 /* Return true iff the function parameter PARAM_DECL was expanded
2671 from the function parameter pack PACK. */
2674 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2676 if (DECL_ARTIFICIAL (param_decl)
2677 || !function_parameter_pack_p (pack))
2680 gcc_assert (DECL_NAME (param_decl) && DECL_NAME (pack));
2682 /* The parameter pack and its pack arguments have the same
2684 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2687 /* Determine whether ARGS describes a variadic template args list,
2688 i.e., one that is terminated by a template argument pack. */
2691 template_args_variadic_p (tree args)
2696 if (args == NULL_TREE)
2699 args = INNERMOST_TEMPLATE_ARGS (args);
2700 nargs = TREE_VEC_LENGTH (args);
2705 last_parm = TREE_VEC_ELT (args, nargs - 1);
2707 return ARGUMENT_PACK_P (last_parm);
2710 /* Generate a new name for the parameter pack name NAME (an
2711 IDENTIFIER_NODE) that incorporates its */
2714 make_ith_pack_parameter_name (tree name, int i)
2716 /* Munge the name to include the parameter index. */
2717 #define NUMBUF_LEN 128
2718 char numbuf[NUMBUF_LEN];
2722 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2723 newname_len = IDENTIFIER_LENGTH (name)
2724 + strlen (numbuf) + 2;
2725 newname = (char*)alloca (newname_len);
2726 snprintf (newname, newname_len,
2727 "%s#%i", IDENTIFIER_POINTER (name), i);
2728 return get_identifier (newname);
2731 /* Return true if T is a primary function
2732 or class template instantiation. */
2735 primary_template_instantiation_p (const_tree t)
2740 if (TREE_CODE (t) == FUNCTION_DECL)
2741 return DECL_LANG_SPECIFIC (t)
2742 && DECL_TEMPLATE_INSTANTIATION (t)
2743 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2744 else if (CLASS_TYPE_P (t))
2745 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2746 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2750 /* Return true if PARM is a template template parameter. */
2753 template_template_parameter_p (const_tree parm)
2755 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2758 /* Return the template parameters of T if T is a
2759 primary template instantiation, NULL otherwise. */
2762 get_primary_template_innermost_parameters (const_tree t)
2764 tree parms = NULL, template_info = NULL;
2766 if ((template_info = get_template_info (t))
2767 && primary_template_instantiation_p (t))
2768 parms = INNERMOST_TEMPLATE_PARMS
2769 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2774 /* Returns the template arguments of T if T is a template instantiation,
2778 get_template_innermost_arguments (const_tree t)
2780 tree args = NULL, template_info = NULL;
2782 if ((template_info = get_template_info (t))
2783 && TI_ARGS (template_info))
2784 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2789 /* Return the argument pack elements of T if T is a template argument pack,
2793 get_template_argument_pack_elems (const_tree t)
2795 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2796 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2799 return ARGUMENT_PACK_ARGS (t);
2802 /* Structure used to track the progress of find_parameter_packs_r. */
2803 struct find_parameter_pack_data
2805 /* TREE_LIST that will contain all of the parameter packs found by
2807 tree* parameter_packs;
2809 /* Set of AST nodes that have been visited by the traversal. */
2810 struct pointer_set_t *visited;
2813 /* Identifies all of the argument packs that occur in a template
2814 argument and appends them to the TREE_LIST inside DATA, which is a
2815 find_parameter_pack_data structure. This is a subroutine of
2816 make_pack_expansion and uses_parameter_packs. */
2818 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2821 struct find_parameter_pack_data* ppd =
2822 (struct find_parameter_pack_data*)data;
2823 bool parameter_pack_p = false;
2825 /* Identify whether this is a parameter pack or not. */
2826 switch (TREE_CODE (t))
2828 case TEMPLATE_PARM_INDEX:
2829 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2830 parameter_pack_p = true;
2833 case TEMPLATE_TYPE_PARM:
2834 case TEMPLATE_TEMPLATE_PARM:
2835 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2836 parameter_pack_p = true;
2840 if (FUNCTION_PARAMETER_PACK_P (t))
2842 /* We don't want to walk into the type of a PARM_DECL,
2843 because we don't want to see the type parameter pack. */
2845 parameter_pack_p = true;
2850 /* Not a parameter pack. */
2854 if (parameter_pack_p)
2856 /* Add this parameter pack to the list. */
2857 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2861 cp_walk_tree (&TYPE_CONTEXT (t),
2862 &find_parameter_packs_r, ppd, ppd->visited);
2864 /* This switch statement will return immediately if we don't find a
2866 switch (TREE_CODE (t))
2868 case TEMPLATE_PARM_INDEX:
2871 case BOUND_TEMPLATE_TEMPLATE_PARM:
2872 /* Check the template itself. */
2873 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2874 &find_parameter_packs_r, ppd, ppd->visited);
2875 /* Check the template arguments. */
2876 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2881 case TEMPLATE_TYPE_PARM:
2882 case TEMPLATE_TEMPLATE_PARM:
2889 if (TYPE_PTRMEMFUNC_P (t))
2895 if (TYPE_TEMPLATE_INFO (t))
2896 cp_walk_tree (&TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
2897 &find_parameter_packs_r, ppd, ppd->visited);
2903 cp_walk_tree (&TREE_TYPE (t),
2904 &find_parameter_packs_r, ppd, ppd->visited);
2908 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
2913 case TYPE_PACK_EXPANSION:
2914 case EXPR_PACK_EXPANSION:
2919 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
2924 case IDENTIFIER_NODE:
2925 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
2937 /* Determines if the expression or type T uses any parameter packs. */
2939 uses_parameter_packs (tree t)
2941 tree parameter_packs = NULL_TREE;
2942 struct find_parameter_pack_data ppd;
2943 ppd.parameter_packs = ¶meter_packs;
2944 ppd.visited = pointer_set_create ();
2945 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2946 pointer_set_destroy (ppd.visited);
2947 return parameter_packs != NULL_TREE;
2950 /* Turn ARG, which may be an expression, type, or a TREE_LIST
2951 representation a base-class initializer into a parameter pack
2952 expansion. If all goes well, the resulting node will be an
2953 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
2956 make_pack_expansion (tree arg)
2959 tree parameter_packs = NULL_TREE;
2960 bool for_types = false;
2961 struct find_parameter_pack_data ppd;
2963 if (!arg || arg == error_mark_node)
2966 if (TREE_CODE (arg) == TREE_LIST)
2968 /* The only time we will see a TREE_LIST here is for a base
2969 class initializer. In this case, the TREE_PURPOSE will be a
2970 _TYPE node (representing the base class expansion we're
2971 initializing) and the TREE_VALUE will be a TREE_LIST
2972 containing the initialization arguments.
2974 The resulting expansion looks somewhat different from most
2975 expansions. Rather than returning just one _EXPANSION, we
2976 return a TREE_LIST whose TREE_PURPOSE is a
2977 TYPE_PACK_EXPANSION containing the bases that will be
2978 initialized. The TREE_VALUE will be identical to the
2979 original TREE_VALUE, which is a list of arguments that will
2980 be passed to each base. We do not introduce any new pack
2981 expansion nodes into the TREE_VALUE (although it is possible
2982 that some already exist), because the TREE_PURPOSE and
2983 TREE_VALUE all need to be expanded together with the same
2984 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
2985 resulting TREE_PURPOSE will mention the parameter packs in
2986 both the bases and the arguments to the bases. */
2989 tree parameter_packs = NULL_TREE;
2991 /* Determine which parameter packs will be used by the base
2993 ppd.visited = pointer_set_create ();
2994 ppd.parameter_packs = ¶meter_packs;
2995 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
2998 if (parameter_packs == NULL_TREE)
3000 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3001 pointer_set_destroy (ppd.visited);
3002 return error_mark_node;
3005 if (TREE_VALUE (arg) != void_type_node)
3007 /* Collect the sets of parameter packs used in each of the
3008 initialization arguments. */
3009 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3011 /* Determine which parameter packs will be expanded in this
3013 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3018 pointer_set_destroy (ppd.visited);
3020 /* Create the pack expansion type for the base type. */
3021 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3022 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3023 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3025 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3026 they will rarely be compared to anything. */
3027 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3029 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3032 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3035 /* Build the PACK_EXPANSION_* node. */
3037 ? cxx_make_type (TYPE_PACK_EXPANSION)
3038 : make_node (EXPR_PACK_EXPANSION);
3039 SET_PACK_EXPANSION_PATTERN (result, arg);
3040 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3042 /* Propagate type and const-expression information. */
3043 TREE_TYPE (result) = TREE_TYPE (arg);
3044 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3047 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3048 they will rarely be compared to anything. */
3049 SET_TYPE_STRUCTURAL_EQUALITY (result);
3051 /* Determine which parameter packs will be expanded. */
3052 ppd.parameter_packs = ¶meter_packs;
3053 ppd.visited = pointer_set_create ();
3054 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3055 pointer_set_destroy (ppd.visited);
3057 /* Make sure we found some parameter packs. */
3058 if (parameter_packs == NULL_TREE)
3061 error ("expansion pattern %<%T%> contains no argument packs", arg);
3063 error ("expansion pattern %<%E%> contains no argument packs", arg);
3064 return error_mark_node;
3066 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3071 /* Checks T for any "bare" parameter packs, which have not yet been
3072 expanded, and issues an error if any are found. This operation can
3073 only be done on full expressions or types (e.g., an expression
3074 statement, "if" condition, etc.), because we could have expressions like:
3076 foo(f(g(h(args)))...)
3078 where "args" is a parameter pack. check_for_bare_parameter_packs
3079 should not be called for the subexpressions args, h(args),
3080 g(h(args)), or f(g(h(args))), because we would produce erroneous
3083 Returns TRUE and emits an error if there were bare parameter packs,
3084 returns FALSE otherwise. */
3086 check_for_bare_parameter_packs (tree t)
3088 tree parameter_packs = NULL_TREE;
3089 struct find_parameter_pack_data ppd;
3091 if (!processing_template_decl || !t || t == error_mark_node)
3094 if (TREE_CODE (t) == TYPE_DECL)
3097 ppd.parameter_packs = ¶meter_packs;
3098 ppd.visited = pointer_set_create ();
3099 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3100 pointer_set_destroy (ppd.visited);
3102 if (parameter_packs)
3104 error ("parameter packs not expanded with %<...%>:");
3105 while (parameter_packs)
3107 tree pack = TREE_VALUE (parameter_packs);
3108 tree name = NULL_TREE;
3110 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3111 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3112 name = TYPE_NAME (pack);
3113 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3114 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3116 name = DECL_NAME (pack);
3119 inform (input_location, " %qD", name);
3121 inform (input_location, " <anonymous>");
3123 parameter_packs = TREE_CHAIN (parameter_packs);
3132 /* Expand any parameter packs that occur in the template arguments in
3135 expand_template_argument_pack (tree args)
3137 tree result_args = NULL_TREE;
3138 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3139 int num_result_args = -1;
3141 /* First, determine if we need to expand anything, and the number of
3142 slots we'll need. */
3143 for (in_arg = 0; in_arg < nargs; ++in_arg)
3145 tree arg = TREE_VEC_ELT (args, in_arg);
3146 if (ARGUMENT_PACK_P (arg))
3148 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3149 if (num_result_args < 0)
3150 num_result_args = in_arg + num_packed;
3152 num_result_args += num_packed;
3156 if (num_result_args >= 0)
3161 /* If no expansion is necessary, we're done. */
3162 if (num_result_args < 0)
3165 /* Expand arguments. */
3166 result_args = make_tree_vec (num_result_args);
3167 for (in_arg = 0; in_arg < nargs; ++in_arg)
3169 tree arg = TREE_VEC_ELT (args, in_arg);
3170 if (ARGUMENT_PACK_P (arg))
3172 tree packed = ARGUMENT_PACK_ARGS (arg);
3173 int i, num_packed = TREE_VEC_LENGTH (packed);
3174 for (i = 0; i < num_packed; ++i, ++out_arg)
3175 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3179 TREE_VEC_ELT (result_args, out_arg) = arg;
3187 /* Checks if DECL shadows a template parameter.
3189 [temp.local]: A template-parameter shall not be redeclared within its
3190 scope (including nested scopes).
3192 Emits an error and returns TRUE if the DECL shadows a parameter,
3193 returns FALSE otherwise. */
3196 check_template_shadow (tree decl)
3200 /* If we're not in a template, we can't possibly shadow a template
3202 if (!current_template_parms)
3205 /* Figure out what we're shadowing. */
3206 if (TREE_CODE (decl) == OVERLOAD)
3207 decl = OVL_CURRENT (decl);
3208 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3210 /* If there's no previous binding for this name, we're not shadowing
3211 anything, let alone a template parameter. */
3215 /* If we're not shadowing a template parameter, we're done. Note
3216 that OLDDECL might be an OVERLOAD (or perhaps even an
3217 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3219 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3222 /* We check for decl != olddecl to avoid bogus errors for using a
3223 name inside a class. We check TPFI to avoid duplicate errors for
3224 inline member templates. */
3226 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3229 error ("declaration of %q+#D", decl);
3230 error (" shadows template parm %q+#D", olddecl);
3234 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3235 ORIG_LEVEL, DECL, and TYPE. */
3238 build_template_parm_index (int index,
3244 tree t = make_node (TEMPLATE_PARM_INDEX);
3245 TEMPLATE_PARM_IDX (t) = index;
3246 TEMPLATE_PARM_LEVEL (t) = level;
3247 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3248 TEMPLATE_PARM_DECL (t) = decl;
3249 TREE_TYPE (t) = type;
3250 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3251 TREE_READONLY (t) = TREE_READONLY (decl);
3256 /* Find the canonical type parameter for the given template type
3257 parameter. Returns the canonical type parameter, which may be TYPE
3258 if no such parameter existed. */
3260 canonical_type_parameter (tree type)
3263 int idx = TEMPLATE_TYPE_IDX (type);
3264 if (!canonical_template_parms)
3265 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3267 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3268 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3270 list = VEC_index (tree, canonical_template_parms, idx);
3271 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3272 list = TREE_CHAIN (list);
3275 return TREE_VALUE (list);
3278 VEC_replace(tree, canonical_template_parms, idx,
3279 tree_cons (NULL_TREE, type,
3280 VEC_index (tree, canonical_template_parms, idx)));
3285 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3286 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3287 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3288 new one is created. */
3291 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3292 tsubst_flags_t complain)
3294 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3295 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3296 != TEMPLATE_PARM_LEVEL (index) - levels))
3298 tree orig_decl = TEMPLATE_PARM_DECL (index);
3301 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3302 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3303 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3304 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3305 DECL_ARTIFICIAL (decl) = 1;
3306 SET_DECL_TEMPLATE_PARM_P (decl);
3308 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3309 TEMPLATE_PARM_LEVEL (index) - levels,
3310 TEMPLATE_PARM_ORIG_LEVEL (index),
3312 TEMPLATE_PARM_DESCENDANTS (index) = t;
3313 TEMPLATE_PARM_PARAMETER_PACK (t)
3314 = TEMPLATE_PARM_PARAMETER_PACK (index);
3316 /* Template template parameters need this. */
3317 if (TREE_CODE (decl) == TEMPLATE_DECL)
3318 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3319 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3323 return TEMPLATE_PARM_DESCENDANTS (index);
3326 /* Process information from new template parameter PARM and append it to the
3327 LIST being built. This new parameter is a non-type parameter iff
3328 IS_NON_TYPE is true. This new parameter is a parameter
3329 pack iff IS_PARAMETER_PACK is true. The location of PARM is in
3333 process_template_parm (tree list, location_t parm_loc, tree parm, bool is_non_type,
3334 bool is_parameter_pack)
3341 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3342 defval = TREE_PURPOSE (parm);
3346 tree p = tree_last (list);
3348 if (p && TREE_VALUE (p) != error_mark_node)
3351 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3352 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3354 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3364 parm = TREE_VALUE (parm);
3366 SET_DECL_TEMPLATE_PARM_P (parm);
3368 if (TREE_TYPE (parm) == error_mark_node)
3370 err_parm_list = build_tree_list (defval, parm);
3371 TREE_VALUE (err_parm_list) = error_mark_node;
3372 return chainon (list, err_parm_list);
3378 The top-level cv-qualifiers on the template-parameter are
3379 ignored when determining its type. */
3380 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3381 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3383 err_parm_list = build_tree_list (defval, parm);
3384 TREE_VALUE (err_parm_list) = error_mark_node;
3385 return chainon (list, err_parm_list);
3388 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3390 /* This template parameter is not a parameter pack, but it
3391 should be. Complain about "bare" parameter packs. */
3392 check_for_bare_parameter_packs (TREE_TYPE (parm));
3394 /* Recover by calling this a parameter pack. */
3395 is_parameter_pack = true;
3399 /* A template parameter is not modifiable. */
3400 TREE_CONSTANT (parm) = 1;
3401 TREE_READONLY (parm) = 1;
3402 decl = build_decl (parm_loc,
3403 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3404 TREE_CONSTANT (decl) = 1;
3405 TREE_READONLY (decl) = 1;
3406 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3407 = build_template_parm_index (idx, processing_template_decl,
3408 processing_template_decl,
3409 decl, TREE_TYPE (parm));
3411 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3412 = is_parameter_pack;
3417 parm = TREE_VALUE (TREE_VALUE (parm));
3419 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3421 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3422 /* This is for distinguishing between real templates and template
3423 template parameters */
3424 TREE_TYPE (parm) = t;
3425 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3430 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3431 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3432 decl = build_decl (parm_loc,
3433 TYPE_DECL, parm, t);
3436 TYPE_NAME (t) = decl;
3437 TYPE_STUB_DECL (t) = decl;
3439 TEMPLATE_TYPE_PARM_INDEX (t)
3440 = build_template_parm_index (idx, processing_template_decl,
3441 processing_template_decl,
3442 decl, TREE_TYPE (parm));
3443 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3444 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3446 DECL_ARTIFICIAL (decl) = 1;
3447 SET_DECL_TEMPLATE_PARM_P (decl);
3449 parm = build_tree_list (defval, parm);
3450 return chainon (list, parm);
3453 /* The end of a template parameter list has been reached. Process the
3454 tree list into a parameter vector, converting each parameter into a more
3455 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3459 end_template_parm_list (tree parms)
3463 tree saved_parmlist = make_tree_vec (list_length (parms));
3465 current_template_parms
3466 = tree_cons (size_int (processing_template_decl),
3467 saved_parmlist, current_template_parms);
3469 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3471 next = TREE_CHAIN (parm);
3472 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3473 TREE_CHAIN (parm) = NULL_TREE;
3476 --processing_template_parmlist;
3478 return saved_parmlist;
3481 /* end_template_decl is called after a template declaration is seen. */
3484 end_template_decl (void)
3486 reset_specialization ();
3488 if (! processing_template_decl)
3491 /* This matches the pushlevel in begin_template_parm_list. */
3494 --processing_template_decl;
3495 current_template_parms = TREE_CHAIN (current_template_parms);
3498 /* Within the declaration of a template, return all levels of template
3499 parameters that apply. The template parameters are represented as
3500 a TREE_VEC, in the form documented in cp-tree.h for template
3504 current_template_args (void)
3507 tree args = NULL_TREE;
3508 int length = TMPL_PARMS_DEPTH (current_template_parms);
3511 /* If there is only one level of template parameters, we do not
3512 create a TREE_VEC of TREE_VECs. Instead, we return a single
3513 TREE_VEC containing the arguments. */
3515 args = make_tree_vec (length);
3517 for (header = current_template_parms; header; header = TREE_CHAIN (header))
3519 tree a = copy_node (TREE_VALUE (header));
3522 TREE_TYPE (a) = NULL_TREE;
3523 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3525 tree t = TREE_VEC_ELT (a, i);
3527 /* T will be a list if we are called from within a
3528 begin/end_template_parm_list pair, but a vector directly
3529 if within a begin/end_member_template_processing pair. */
3530 if (TREE_CODE (t) == TREE_LIST)
3534 if (!error_operand_p (t))
3536 if (TREE_CODE (t) == TYPE_DECL
3537 || TREE_CODE (t) == TEMPLATE_DECL)
3541 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3543 /* Turn this argument into a TYPE_ARGUMENT_PACK
3544 with a single element, which expands T. */
3545 tree vec = make_tree_vec (1);
3546 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3548 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3549 SET_ARGUMENT_PACK_ARGS (t, vec);
3554 t = DECL_INITIAL (t);
3556 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3558 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3559 with a single element, which expands T. */
3560 tree vec = make_tree_vec (1);
3561 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3562 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3564 t = make_node (NONTYPE_ARGUMENT_PACK);
3565 SET_ARGUMENT_PACK_ARGS (t, vec);
3566 TREE_TYPE (t) = type;
3569 TREE_VEC_ELT (a, i) = t;
3575 TREE_VEC_ELT (args, --l) = a;
3583 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3584 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3585 a member template. Used by push_template_decl below. */
3588 build_template_decl (tree decl, tree parms, bool member_template_p)
3590 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3591 DECL_TEMPLATE_PARMS (tmpl) = parms;
3592 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3593 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3598 struct template_parm_data
3600 /* The level of the template parameters we are currently
3604 /* The index of the specialization argument we are currently
3608 /* An array whose size is the number of template parameters. The
3609 elements are nonzero if the parameter has been used in any one
3610 of the arguments processed so far. */
3613 /* An array whose size is the number of template arguments. The
3614 elements are nonzero if the argument makes use of template
3615 parameters of this level. */
3616 int* arg_uses_template_parms;
3619 /* Subroutine of push_template_decl used to see if each template
3620 parameter in a partial specialization is used in the explicit
3621 argument list. If T is of the LEVEL given in DATA (which is
3622 treated as a template_parm_data*), then DATA->PARMS is marked
3626 mark_template_parm (tree t, void* data)
3630 struct template_parm_data* tpd = (struct template_parm_data*) data;
3632 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3634 level = TEMPLATE_PARM_LEVEL (t);
3635 idx = TEMPLATE_PARM_IDX (t);
3639 level = TEMPLATE_TYPE_LEVEL (t);
3640 idx = TEMPLATE_TYPE_IDX (t);
3643 if (level == tpd->level)
3645 tpd->parms[idx] = 1;
3646 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
3649 /* Return zero so that for_each_template_parm will continue the
3650 traversal of the tree; we want to mark *every* template parm. */
3654 /* Process the partial specialization DECL. */
3657 process_partial_specialization (tree decl)
3659 tree type = TREE_TYPE (decl);
3660 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
3661 tree specargs = CLASSTYPE_TI_ARGS (type);
3662 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
3663 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
3665 int nargs = TREE_VEC_LENGTH (inner_args);
3668 int did_error_intro = 0;
3669 struct template_parm_data tpd;
3670 struct template_parm_data tpd2;
3672 gcc_assert (current_template_parms);
3674 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3675 ntparms = TREE_VEC_LENGTH (inner_parms);
3677 /* We check that each of the template parameters given in the
3678 partial specialization is used in the argument list to the
3679 specialization. For example:
3681 template <class T> struct S;
3682 template <class T> struct S<T*>;
3684 The second declaration is OK because `T*' uses the template
3685 parameter T, whereas
3687 template <class T> struct S<int>;
3689 is no good. Even trickier is:
3700 The S2<T> declaration is actually invalid; it is a
3701 full-specialization. Of course,
3704 struct S2<T (*)(U)>;
3706 or some such would have been OK. */
3707 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
3708 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
3709 memset (tpd.parms, 0, sizeof (int) * ntparms);
3711 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
3712 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
3713 for (i = 0; i < nargs; ++i)
3715 tpd.current_arg = i;
3716 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
3717 &mark_template_parm,
3720 /*include_nondeduced_p=*/false);
3722 for (i = 0; i < ntparms; ++i)
3723 if (tpd.parms[i] == 0)
3725 /* One of the template parms was not used in the
3727 if (!did_error_intro)
3729 error ("template parameters not used in partial specialization:");
3730 did_error_intro = 1;
3733 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
3736 /* [temp.class.spec]
3738 The argument list of the specialization shall not be identical to
3739 the implicit argument list of the primary template. */
3740 if (comp_template_args
3742 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
3744 error ("partial specialization %qT does not specialize any template arguments", type);
3746 /* [temp.class.spec]
3748 A partially specialized non-type argument expression shall not
3749 involve template parameters of the partial specialization except
3750 when the argument expression is a simple identifier.
3752 The type of a template parameter corresponding to a specialized
3753 non-type argument shall not be dependent on a parameter of the
3756 Also, we verify that pack expansions only occur at the
3757 end of the argument list. */
3758 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
3760 for (i = 0; i < nargs; ++i)
3762 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
3763 tree arg = TREE_VEC_ELT (inner_args, i);
3764 tree packed_args = NULL_TREE;
3767 if (ARGUMENT_PACK_P (arg))
3769 /* Extract the arguments from the argument pack. We'll be
3770 iterating over these in the following loop. */
3771 packed_args = ARGUMENT_PACK_ARGS (arg);
3772 len = TREE_VEC_LENGTH (packed_args);
3775 for (j = 0; j < len; j++)
3778 /* Get the Jth argument in the parameter pack. */
3779 arg = TREE_VEC_ELT (packed_args, j);
3781 if (PACK_EXPANSION_P (arg))
3783 /* Pack expansions must come at the end of the
3785 if ((packed_args && j < len - 1)
3786 || (!packed_args && i < nargs - 1))
3788 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3789 error ("parameter pack argument %qE must be at the end of the template argument list", arg);
3791 error ("parameter pack argument %qT must be at the end of the template argument list", arg);
3794 TREE_VEC_ELT (packed_args, j) = error_mark_node;
3798 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3799 /* We only care about the pattern. */
3800 arg = PACK_EXPANSION_PATTERN (arg);
3802 if (/* These first two lines are the `non-type' bit. */
3804 && TREE_CODE (arg) != TEMPLATE_DECL
3805 /* This next line is the `argument expression is not just a
3806 simple identifier' condition and also the `specialized
3807 non-type argument' bit. */
3808 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
3810 if ((!packed_args && tpd.arg_uses_template_parms[i])
3811 || (packed_args && uses_template_parms (arg)))
3812 error ("template argument %qE involves template parameter(s)",
3816 /* Look at the corresponding template parameter,
3817 marking which template parameters its type depends
3819 tree type = TREE_TYPE (parm);
3823 /* We haven't yet initialized TPD2. Do so now. */
3824 tpd2.arg_uses_template_parms
3825 = (int *) alloca (sizeof (int) * nargs);
3826 /* The number of parameters here is the number in the
3827 main template, which, as checked in the assertion
3829 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
3831 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
3834 /* Mark the template parameters. But this time, we're
3835 looking for the template parameters of the main
3836 template, not in the specialization. */
3837 tpd2.current_arg = i;
3838 tpd2.arg_uses_template_parms[i] = 0;
3839 memset (tpd2.parms, 0, sizeof (int) * nargs);
3840 for_each_template_parm (type,
3841 &mark_template_parm,
3844 /*include_nondeduced_p=*/false);
3846 if (tpd2.arg_uses_template_parms [i])
3848 /* The type depended on some template parameters.
3849 If they are fully specialized in the
3850 specialization, that's OK. */
3852 for (j = 0; j < nargs; ++j)
3853 if (tpd2.parms[j] != 0
3854 && tpd.arg_uses_template_parms [j])
3856 error ("type %qT of template argument %qE depends "
3857 "on template parameter(s)",
3868 /* We should only get here once. */
3869 gcc_assert (!COMPLETE_TYPE_P (type));
3871 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
3872 = tree_cons (specargs, inner_parms,
3873 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
3874 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
3878 /* Check that a template declaration's use of default arguments and
3879 parameter packs is not invalid. Here, PARMS are the template
3880 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
3881 a primary template. IS_PARTIAL is nonzero if DECL is a partial
3885 IS_FRIEND_DECL is nonzero if DECL is a friend function template
3886 declaration (but not a definition); 1 indicates a declaration, 2
3887 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
3888 emitted for extraneous default arguments.
3890 Returns TRUE if there were no errors found, FALSE otherwise. */
3893 check_default_tmpl_args (tree decl, tree parms, int is_primary,
3894 int is_partial, int is_friend_decl)
3897 int last_level_to_check;
3899 bool no_errors = true;
3903 A default template-argument shall not be specified in a
3904 function template declaration or a function template definition, nor
3905 in the template-parameter-list of the definition of a member of a
3908 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
3909 /* You can't have a function template declaration in a local
3910 scope, nor you can you define a member of a class template in a
3914 if (current_class_type
3915 && !TYPE_BEING_DEFINED (current_class_type)
3916 && DECL_LANG_SPECIFIC (decl)
3917 && DECL_DECLARES_FUNCTION_P (decl)
3918 /* If this is either a friend defined in the scope of the class
3919 or a member function. */
3920 && (DECL_FUNCTION_MEMBER_P (decl)
3921 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
3922 : DECL_FRIEND_CONTEXT (decl)
3923 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
3925 /* And, if it was a member function, it really was defined in
3926 the scope of the class. */
3927 && (!DECL_FUNCTION_MEMBER_P (decl)
3928 || DECL_INITIALIZED_IN_CLASS_P (decl)))
3929 /* We already checked these parameters when the template was
3930 declared, so there's no need to do it again now. This function
3931 was defined in class scope, but we're processing it's body now
3932 that the class is complete. */
3935 /* Core issue 226 (C++0x only): the following only applies to class
3937 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
3941 If a template-parameter has a default template-argument, all
3942 subsequent template-parameters shall have a default
3943 template-argument supplied. */
3944 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
3946 tree inner_parms = TREE_VALUE (parm_level);
3947 int ntparms = TREE_VEC_LENGTH (inner_parms);
3948 int seen_def_arg_p = 0;
3951 for (i = 0; i < ntparms; ++i)
3953 tree parm = TREE_VEC_ELT (inner_parms, i);
3955 if (parm == error_mark_node)
3958 if (TREE_PURPOSE (parm))
3960 else if (seen_def_arg_p
3961 && !template_parameter_pack_p (TREE_VALUE (parm)))
3963 error ("no default argument for %qD", TREE_VALUE (parm));
3964 /* For better subsequent error-recovery, we indicate that
3965 there should have been a default argument. */
3966 TREE_PURPOSE (parm) = error_mark_node;
3972 /* Don't complain about an enclosing partial
3974 && parm_level == parms
3975 && TREE_CODE (decl) == TYPE_DECL
3977 && template_parameter_pack_p (TREE_VALUE (parm)))
3979 /* A primary class template can only have one
3980 parameter pack, at the end of the template
3983 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
3984 error ("parameter pack %qE must be at the end of the"
3985 " template parameter list", TREE_VALUE (parm));
3987 error ("parameter pack %qT must be at the end of the"
3988 " template parameter list",
3989 TREE_TYPE (TREE_VALUE (parm)));
3991 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
3999 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4003 /* For an ordinary class template, default template arguments are
4004 allowed at the innermost level, e.g.:
4005 template <class T = int>
4007 but, in a partial specialization, they're not allowed even
4008 there, as we have in [temp.class.spec]:
4010 The template parameter list of a specialization shall not
4011 contain default template argument values.
4013 So, for a partial specialization, or for a function template
4014 (in C++98/C++03), we look at all of them. */
4017 /* But, for a primary class template that is not a partial
4018 specialization we look at all template parameters except the
4020 parms = TREE_CHAIN (parms);
4022 /* Figure out what error message to issue. */
4023 if (is_friend_decl == 2)
4024 msg = "default template arguments may not be used in function template friend re-declaration";
4025 else if (is_friend_decl)
4026 msg = "default template arguments may not be used in function template friend declarations";
4027 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4028 msg = ("default template arguments may not be used in function templates "
4029 "without -std=c++0x or -std=gnu++0x");
4030 else if (is_partial)
4031 msg = "default template arguments may not be used in partial specializations";
4033 msg = "default argument for template parameter for class enclosing %qD";
4035 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4036 /* If we're inside a class definition, there's no need to
4037 examine the parameters to the class itself. On the one
4038 hand, they will be checked when the class is defined, and,
4039 on the other, default arguments are valid in things like:
4040 template <class T = double>
4041 struct S { template <class U> void f(U); };
4042 Here the default argument for `S' has no bearing on the
4043 declaration of `f'. */
4044 last_level_to_check = template_class_depth (current_class_type) + 1;
4046 /* Check everything. */
4047 last_level_to_check = 0;
4049 for (parm_level = parms;
4050 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4051 parm_level = TREE_CHAIN (parm_level))
4053 tree inner_parms = TREE_VALUE (parm_level);
4057 ntparms = TREE_VEC_LENGTH (inner_parms);
4058 for (i = 0; i < ntparms; ++i)
4060 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4063 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4068 if (is_friend_decl == 2)
4075 /* Clear out the default argument so that we are not
4077 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4081 /* At this point, if we're still interested in issuing messages,
4082 they must apply to classes surrounding the object declared. */
4084 msg = "default argument for template parameter for class enclosing %qD";
4090 /* Worker for push_template_decl_real, called via
4091 for_each_template_parm. DATA is really an int, indicating the
4092 level of the parameters we are interested in. If T is a template
4093 parameter of that level, return nonzero. */
4096 template_parm_this_level_p (tree t, void* data)
4098 int this_level = *(int *)data;
4101 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4102 level = TEMPLATE_PARM_LEVEL (t);
4104 level = TEMPLATE_TYPE_LEVEL (t);
4105 return level == this_level;
4108 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4109 parameters given by current_template_args, or reuses a
4110 previously existing one, if appropriate. Returns the DECL, or an
4111 equivalent one, if it is replaced via a call to duplicate_decls.
4113 If IS_FRIEND is true, DECL is a friend declaration. */
4116 push_template_decl_real (tree decl, bool is_friend)
4124 int new_template_p = 0;
4125 /* True if the template is a member template, in the sense of
4127 bool member_template_p = false;
4129 if (decl == error_mark_node || !current_template_parms)
4130 return error_mark_node;
4132 /* See if this is a partial specialization. */
4133 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4134 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4135 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4137 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4141 /* For a friend, we want the context of the friend function, not
4142 the type of which it is a friend. */
4143 ctx = DECL_CONTEXT (decl);
4144 else if (CP_DECL_CONTEXT (decl)
4145 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4146 /* In the case of a virtual function, we want the class in which
4148 ctx = CP_DECL_CONTEXT (decl);
4150 /* Otherwise, if we're currently defining some class, the DECL
4151 is assumed to be a member of the class. */
4152 ctx = current_scope ();
4154 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4157 if (!DECL_CONTEXT (decl))
4158 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4160 /* See if this is a primary template. */
4161 if (is_friend && ctx)
4162 /* A friend template that specifies a class context, i.e.
4163 template <typename T> friend void A<T>::f();
4167 primary = template_parm_scope_p ();
4171 if (DECL_CLASS_SCOPE_P (decl))
4172 member_template_p = true;
4173 if (TREE_CODE (decl) == TYPE_DECL
4174 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4176 error ("template class without a name");
4177 return error_mark_node;
4179 else if (TREE_CODE (decl) == FUNCTION_DECL)
4181 if (DECL_DESTRUCTOR_P (decl))
4185 A destructor shall not be a member template. */
4186 error ("destructor %qD declared as member template", decl);
4187 return error_mark_node;
4189 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4190 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
4191 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4192 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4193 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4194 == void_list_node)))
4196 /* [basic.stc.dynamic.allocation]
4198 An allocation function can be a function
4199 template. ... Template allocation functions shall
4200 have two or more parameters. */
4201 error ("invalid template declaration of %qD", decl);
4202 return error_mark_node;
4205 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4206 && CLASS_TYPE_P (TREE_TYPE (decl)))
4210 error ("template declaration of %q#D", decl);
4211 return error_mark_node;
4215 /* Check to see that the rules regarding the use of default
4216 arguments are not being violated. */
4217 check_default_tmpl_args (decl, current_template_parms,
4218 primary, is_partial, /*is_friend_decl=*/0);
4220 /* Ensure that there are no parameter packs in the type of this
4221 declaration that have not been expanded. */
4222 if (TREE_CODE (decl) == FUNCTION_DECL)
4224 /* Check each of the arguments individually to see if there are
4225 any bare parameter packs. */
4226 tree type = TREE_TYPE (decl);
4227 tree arg = DECL_ARGUMENTS (decl);
4228 tree argtype = TYPE_ARG_TYPES (type);
4230 while (arg && argtype)
4232 if (!FUNCTION_PARAMETER_PACK_P (arg)
4233 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4235 /* This is a PARM_DECL that contains unexpanded parameter
4236 packs. We have already complained about this in the
4237 check_for_bare_parameter_packs call, so just replace
4238 these types with ERROR_MARK_NODE. */
4239 TREE_TYPE (arg) = error_mark_node;
4240 TREE_VALUE (argtype) = error_mark_node;
4243 arg = TREE_CHAIN (arg);
4244 argtype = TREE_CHAIN (argtype);
4247 /* Check for bare parameter packs in the return type and the
4248 exception specifiers. */
4249 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4250 /* Errors were already issued, set return type to int
4251 as the frontend doesn't expect error_mark_node as
4253 TREE_TYPE (type) = integer_type_node;
4254 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4255 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4257 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4259 TREE_TYPE (decl) = error_mark_node;
4260 return error_mark_node;
4264 return process_partial_specialization (decl);
4266 args = current_template_args ();
4269 || TREE_CODE (ctx) == FUNCTION_DECL
4270 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4271 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4273 if (DECL_LANG_SPECIFIC (decl)
4274 && DECL_TEMPLATE_INFO (decl)
4275 && DECL_TI_TEMPLATE (decl))
4276 tmpl = DECL_TI_TEMPLATE (decl);
4277 /* If DECL is a TYPE_DECL for a class-template, then there won't
4278 be DECL_LANG_SPECIFIC. The information equivalent to
4279 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4280 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4281 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4282 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4284 /* Since a template declaration already existed for this
4285 class-type, we must be redeclaring it here. Make sure
4286 that the redeclaration is valid. */
4287 redeclare_class_template (TREE_TYPE (decl),
4288 current_template_parms);
4289 /* We don't need to create a new TEMPLATE_DECL; just use the
4290 one we already had. */
4291 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4295 tmpl = build_template_decl (decl, current_template_parms,
4299 if (DECL_LANG_SPECIFIC (decl)
4300 && DECL_TEMPLATE_SPECIALIZATION (decl))
4302 /* A specialization of a member template of a template
4304 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4305 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4306 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4312 tree a, t, current, parms;
4314 tree tinfo = get_template_info (decl);
4318 error ("template definition of non-template %q#D", decl);
4319 return error_mark_node;
4322 tmpl = TI_TEMPLATE (tinfo);
4324 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4325 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4326 && DECL_TEMPLATE_SPECIALIZATION (decl)
4327 && DECL_MEMBER_TEMPLATE_P (tmpl))
4331 /* The declaration is a specialization of a member
4332 template, declared outside the class. Therefore, the
4333 innermost template arguments will be NULL, so we
4334 replace them with the arguments determined by the
4335 earlier call to check_explicit_specialization. */
4336 args = DECL_TI_ARGS (decl);
4339 = build_template_decl (decl, current_template_parms,
4341 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4342 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4343 DECL_TI_TEMPLATE (decl) = new_tmpl;
4344 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4345 DECL_TEMPLATE_INFO (new_tmpl)
4346 = tree_cons (tmpl, args, NULL_TREE);
4348 register_specialization (new_tmpl,
4349 most_general_template (tmpl),
4355 /* Make sure the template headers we got make sense. */
4357 parms = DECL_TEMPLATE_PARMS (tmpl);
4358 i = TMPL_PARMS_DEPTH (parms);
4359 if (TMPL_ARGS_DEPTH (args) != i)
4361 error ("expected %d levels of template parms for %q#D, got %d",
4362 i, decl, TMPL_ARGS_DEPTH (args));
4365 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4367 a = TMPL_ARGS_LEVEL (args, i);
4368 t = INNERMOST_TEMPLATE_PARMS (parms);
4370 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4372 if (current == decl)
4373 error ("got %d template parameters for %q#D",
4374 TREE_VEC_LENGTH (a), decl);
4376 error ("got %d template parameters for %q#T",
4377 TREE_VEC_LENGTH (a), current);
4378 error (" but %d required", TREE_VEC_LENGTH (t));
4379 return error_mark_node;
4382 if (current == decl)
4385 current = (TYPE_P (current)
4386 ? TYPE_CONTEXT (current)
4387 : DECL_CONTEXT (current));
4390 /* Check that the parms are used in the appropriate qualifying scopes
4391 in the declarator. */
4392 if (!comp_template_args
4394 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4397 template arguments to %qD do not match original template %qD",
4398 decl, DECL_TEMPLATE_RESULT (tmpl));
4399 if (!uses_template_parms (TI_ARGS (tinfo)))
4400 inform (input_location, "use template<> for an explicit specialization");
4401 /* Avoid crash in import_export_decl. */
4402 DECL_INTERFACE_KNOWN (decl) = 1;
4403 return error_mark_node;
4407 DECL_TEMPLATE_RESULT (tmpl) = decl;
4408 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4410 /* Push template declarations for global functions and types. Note
4411 that we do not try to push a global template friend declared in a
4412 template class; such a thing may well depend on the template
4413 parameters of the class. */
4414 if (new_template_p && !ctx
4415 && !(is_friend && template_class_depth (current_class_type) > 0))
4417 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4418 if (tmpl == error_mark_node)
4419 return error_mark_node;
4421 /* Hide template friend classes that haven't been declared yet. */
4422 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4424 DECL_ANTICIPATED (tmpl) = 1;
4425 DECL_FRIEND_P (tmpl) = 1;
4431 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4434 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4435 if (DECL_CONV_FN_P (tmpl))
4437 int depth = TMPL_PARMS_DEPTH (parms);
4439 /* It is a conversion operator. See if the type converted to
4440 depends on innermost template operands. */
4442 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4444 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4447 /* Give template template parms a DECL_CONTEXT of the template
4448 for which they are a parameter. */
4449 parms = INNERMOST_TEMPLATE_PARMS (parms);
4450 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4452 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4453 if (TREE_CODE (parm) == TEMPLATE_DECL)
4454 DECL_CONTEXT (parm) = tmpl;
4458 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4459 back to its most general template. If TMPL is a specialization,
4460 ARGS may only have the innermost set of arguments. Add the missing
4461 argument levels if necessary. */
4462 if (DECL_TEMPLATE_INFO (tmpl))
4463 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4465 info = tree_cons (tmpl, args, NULL_TREE);
4467 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4468 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4469 else if (DECL_LANG_SPECIFIC (decl))
4470 DECL_TEMPLATE_INFO (decl) = info;
4472 return DECL_TEMPLATE_RESULT (tmpl);
4476 push_template_decl (tree decl)
4478 return push_template_decl_real (decl, false);
4481 /* Called when a class template TYPE is redeclared with the indicated
4482 template PARMS, e.g.:
4484 template <class T> struct S;
4485 template <class T> struct S {}; */
4488 redeclare_class_template (tree type, tree parms)
4494 if (!TYPE_TEMPLATE_INFO (type))
4496 error ("%qT is not a template type", type);
4500 tmpl = TYPE_TI_TEMPLATE (type);
4501 if (!PRIMARY_TEMPLATE_P (tmpl))
4502 /* The type is nested in some template class. Nothing to worry
4503 about here; there are no new template parameters for the nested
4509 error ("template specifiers not specified in declaration of %qD",
4514 parms = INNERMOST_TEMPLATE_PARMS (parms);
4515 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4517 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4519 error ("redeclared with %d template parameter(s)",
4520 TREE_VEC_LENGTH (parms));
4521 inform (input_location, "previous declaration %q+D used %d template parameter(s)",
4522 tmpl, TREE_VEC_LENGTH (tmpl_parms));
4526 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4533 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4534 || TREE_VEC_ELT (parms, i) == error_mark_node)
4537 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4538 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4539 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4540 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4542 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
4544 if (tmpl_parm != error_mark_node
4545 && (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
4546 || (TREE_CODE (tmpl_parm) != TYPE_DECL
4547 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
4548 || (TREE_CODE (tmpl_parm) != PARM_DECL
4549 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
4550 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
4551 || (TREE_CODE (tmpl_parm) == PARM_DECL
4552 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
4553 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))))))
4555 error ("template parameter %q+#D", tmpl_parm);
4556 error ("redeclared here as %q#D", parm);
4560 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
4562 /* We have in [temp.param]:
4564 A template-parameter may not be given default arguments
4565 by two different declarations in the same scope. */
4566 error_at (input_location, "redefinition of default argument for %q#D", parm);
4567 inform (DECL_SOURCE_LOCATION (tmpl_parm),
4568 "original definition appeared here");
4572 if (parm_default != NULL_TREE)
4573 /* Update the previous template parameters (which are the ones
4574 that will really count) with the new default value. */
4575 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
4576 else if (tmpl_default != NULL_TREE)
4577 /* Update the new parameters, too; they'll be used as the
4578 parameters for any members. */
4579 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
4585 /* Simplify EXPR if it is a non-dependent expression. Returns the
4586 (possibly simplified) expression. */
4589 fold_non_dependent_expr (tree expr)
4591 if (expr == NULL_TREE)
4594 /* If we're in a template, but EXPR isn't value dependent, simplify
4595 it. We're supposed to treat:
4597 template <typename T> void f(T[1 + 1]);
4598 template <typename T> void f(T[2]);
4600 as two declarations of the same function, for example. */
4601 if (processing_template_decl
4602 && !type_dependent_expression_p (expr)
4603 && !value_dependent_expression_p (expr))
4605 HOST_WIDE_INT saved_processing_template_decl;
4607 saved_processing_template_decl = processing_template_decl;
4608 processing_template_decl = 0;
4609 expr = tsubst_copy_and_build (expr,
4612 /*in_decl=*/NULL_TREE,
4613 /*function_p=*/false,
4614 /*integral_constant_expression_p=*/true);
4615 processing_template_decl = saved_processing_template_decl;
4620 /* EXPR is an expression which is used in a constant-expression context.
4621 For instance, it could be a VAR_DECL with a constant initializer.
4622 Extract the innermost constant expression.
4624 This is basically a more powerful version of
4625 integral_constant_value, which can be used also in templates where
4626 initializers can maintain a syntactic rather than semantic form
4627 (even if they are non-dependent, for access-checking purposes). */
4630 fold_decl_constant_value (tree expr)
4632 tree const_expr = expr;
4635 expr = fold_non_dependent_expr (const_expr);
4636 const_expr = integral_constant_value (expr);
4638 while (expr != const_expr);
4643 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
4644 must be a function or a pointer-to-function type, as specified
4645 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
4646 and check that the resulting function has external linkage. */
4649 convert_nontype_argument_function (tree type, tree expr)
4654 fn = instantiate_type (type, fns, tf_none);
4655 if (fn == error_mark_node)
4656 return error_mark_node;
4659 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
4660 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
4661 if (TREE_CODE (fn_no_ptr) == BASELINK)
4662 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
4664 /* [temp.arg.nontype]/1
4666 A template-argument for a non-type, non-template template-parameter
4669 -- the address of an object or function with external linkage. */
4670 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
4672 error ("%qE is not a valid template argument for type %qT "
4673 "because function %qD has not external linkage",
4674 expr, type, fn_no_ptr);
4681 /* Attempt to convert the non-type template parameter EXPR to the
4682 indicated TYPE. If the conversion is successful, return the
4683 converted value. If the conversion is unsuccessful, return
4684 NULL_TREE if we issued an error message, or error_mark_node if we
4685 did not. We issue error messages for out-and-out bad template
4686 parameters, but not simply because the conversion failed, since we
4687 might be just trying to do argument deduction. Both TYPE and EXPR
4688 must be non-dependent.
4690 The conversion follows the special rules described in
4691 [temp.arg.nontype], and it is much more strict than an implicit
4694 This function is called twice for each template argument (see
4695 lookup_template_class for a more accurate description of this
4696 problem). This means that we need to handle expressions which
4697 are not valid in a C++ source, but can be created from the
4698 first call (for instance, casts to perform conversions). These
4699 hacks can go away after we fix the double coercion problem. */
4702 convert_nontype_argument (tree type, tree expr)
4706 /* Detect immediately string literals as invalid non-type argument.
4707 This special-case is not needed for correctness (we would easily
4708 catch this later), but only to provide better diagnostic for this
4709 common user mistake. As suggested by DR 100, we do not mention
4710 linkage issues in the diagnostic as this is not the point. */
4711 if (TREE_CODE (expr) == STRING_CST)
4713 error ("%qE is not a valid template argument for type %qT "
4714 "because string literals can never be used in this context",
4719 /* If we are in a template, EXPR may be non-dependent, but still
4720 have a syntactic, rather than semantic, form. For example, EXPR
4721 might be a SCOPE_REF, rather than the VAR_DECL to which the
4722 SCOPE_REF refers. Preserving the qualifying scope is necessary
4723 so that access checking can be performed when the template is
4724 instantiated -- but here we need the resolved form so that we can
4725 convert the argument. */
4726 expr = fold_non_dependent_expr (expr);
4727 if (error_operand_p (expr))
4728 return error_mark_node;
4729 expr_type = TREE_TYPE (expr);
4731 /* HACK: Due to double coercion, we can get a
4732 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
4733 which is the tree that we built on the first call (see
4734 below when coercing to reference to object or to reference to
4735 function). We just strip everything and get to the arg.
4736 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
4738 if (TREE_CODE (expr) == NOP_EXPR)
4740 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
4742 /* ??? Maybe we could use convert_from_reference here, but we
4743 would need to relax its constraints because the NOP_EXPR
4744 could actually change the type to something more cv-qualified,
4745 and this is not folded by convert_from_reference. */
4746 tree addr = TREE_OPERAND (expr, 0);
4747 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
4748 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
4749 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
4750 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4751 (TREE_TYPE (expr_type),
4752 TREE_TYPE (TREE_TYPE (addr))));
4754 expr = TREE_OPERAND (addr, 0);
4755 expr_type = TREE_TYPE (expr);
4758 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
4759 parameter is a pointer to object, through decay and
4760 qualification conversion. Let's strip everything. */
4761 else if (TYPE_PTROBV_P (type))
4764 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
4765 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
4766 /* Skip the ADDR_EXPR only if it is part of the decay for
4767 an array. Otherwise, it is part of the original argument
4768 in the source code. */
4769 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
4770 expr = TREE_OPERAND (expr, 0);
4771 expr_type = TREE_TYPE (expr);
4775 /* [temp.arg.nontype]/5, bullet 1
4777 For a non-type template-parameter of integral or enumeration type,
4778 integral promotions (_conv.prom_) and integral conversions
4779 (_conv.integral_) are applied. */
4780 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
4782 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (expr_type))
4783 return error_mark_node;
4785 expr = fold_decl_constant_value (expr);
4786 /* Notice that there are constant expressions like '4 % 0' which
4787 do not fold into integer constants. */
4788 if (TREE_CODE (expr) != INTEGER_CST)
4790 error ("%qE is not a valid template argument for type %qT "
4791 "because it is a non-constant expression", expr, type);
4795 /* At this point, an implicit conversion does what we want,
4796 because we already know that the expression is of integral
4798 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
4799 if (expr == error_mark_node)
4800 return error_mark_node;
4802 /* Conversion was allowed: fold it to a bare integer constant. */
4805 /* [temp.arg.nontype]/5, bullet 2
4807 For a non-type template-parameter of type pointer to object,
4808 qualification conversions (_conv.qual_) and the array-to-pointer
4809 conversion (_conv.array_) are applied. */
4810 else if (TYPE_PTROBV_P (type))
4812 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
4814 A template-argument for a non-type, non-template template-parameter
4815 shall be one of: [...]
4817 -- the name of a non-type template-parameter;
4818 -- the address of an object or function with external linkage, [...]
4819 expressed as "& id-expression" where the & is optional if the name
4820 refers to a function or array, or if the corresponding
4821 template-parameter is a reference.
4823 Here, we do not care about functions, as they are invalid anyway
4824 for a parameter of type pointer-to-object. */
4826 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
4827 /* Non-type template parameters are OK. */
4829 else if (TREE_CODE (expr) != ADDR_EXPR
4830 && TREE_CODE (expr_type) != ARRAY_TYPE)
4832 if (TREE_CODE (expr) == VAR_DECL)
4834 error ("%qD is not a valid template argument "
4835 "because %qD is a variable, not the address of "
4840 /* Other values, like integer constants, might be valid
4841 non-type arguments of some other type. */
4842 return error_mark_node;
4848 decl = ((TREE_CODE (expr) == ADDR_EXPR)
4849 ? TREE_OPERAND (expr, 0) : expr);
4850 if (TREE_CODE (decl) != VAR_DECL)
4852 error ("%qE is not a valid template argument of type %qT "
4853 "because %qE is not a variable",
4857 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
4859 error ("%qE is not a valid template argument of type %qT "
4860 "because %qD does not have external linkage",
4866 expr = decay_conversion (expr);
4867 if (expr == error_mark_node)
4868 return error_mark_node;
4870 expr = perform_qualification_conversions (type, expr);
4871 if (expr == error_mark_node)
4872 return error_mark_node;
4874 /* [temp.arg.nontype]/5, bullet 3
4876 For a non-type template-parameter of type reference to object, no
4877 conversions apply. The type referred to by the reference may be more
4878 cv-qualified than the (otherwise identical) type of the
4879 template-argument. The template-parameter is bound directly to the
4880 template-argument, which must be an lvalue. */
4881 else if (TYPE_REF_OBJ_P (type))
4883 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
4885 return error_mark_node;
4887 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
4889 error ("%qE is not a valid template argument for type %qT "
4890 "because of conflicts in cv-qualification", expr, type);
4894 if (!real_lvalue_p (expr))
4896 error ("%qE is not a valid template argument for type %qT "
4897 "because it is not an lvalue", expr, type);
4901 /* [temp.arg.nontype]/1
4903 A template-argument for a non-type, non-template template-parameter
4904 shall be one of: [...]
4906 -- the address of an object or function with external linkage. */
4907 if (!DECL_EXTERNAL_LINKAGE_P (expr))
4909 error ("%qE is not a valid template argument for type %qT "
4910 "because object %qD has not external linkage",
4915 expr = build_nop (type, build_address (expr));
4917 /* [temp.arg.nontype]/5, bullet 4
4919 For a non-type template-parameter of type pointer to function, only
4920 the function-to-pointer conversion (_conv.func_) is applied. If the
4921 template-argument represents a set of overloaded functions (or a
4922 pointer to such), the matching function is selected from the set
4924 else if (TYPE_PTRFN_P (type))
4926 /* If the argument is a template-id, we might not have enough
4927 context information to decay the pointer. */
4928 if (!type_unknown_p (expr_type))
4930 expr = decay_conversion (expr);
4931 if (expr == error_mark_node)
4932 return error_mark_node;
4935 expr = convert_nontype_argument_function (type, expr);
4936 if (!expr || expr == error_mark_node)
4939 if (TREE_CODE (expr) != ADDR_EXPR)
4941 error ("%qE is not a valid template argument for type %qT", expr, type);
4942 error ("it must be the address of a function with external linkage");
4946 /* [temp.arg.nontype]/5, bullet 5
4948 For a non-type template-parameter of type reference to function, no
4949 conversions apply. If the template-argument represents a set of
4950 overloaded functions, the matching function is selected from the set
4952 else if (TYPE_REFFN_P (type))
4954 if (TREE_CODE (expr) == ADDR_EXPR)
4956 error ("%qE is not a valid template argument for type %qT "
4957 "because it is a pointer", expr, type);
4958 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
4962 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
4963 if (!expr || expr == error_mark_node)
4966 expr = build_nop (type, build_address (expr));
4968 /* [temp.arg.nontype]/5, bullet 6
4970 For a non-type template-parameter of type pointer to member function,
4971 no conversions apply. If the template-argument represents a set of
4972 overloaded member functions, the matching member function is selected
4973 from the set (_over.over_). */
4974 else if (TYPE_PTRMEMFUNC_P (type))
4976 expr = instantiate_type (type, expr, tf_none);
4977 if (expr == error_mark_node)
4978 return error_mark_node;
4980 /* There is no way to disable standard conversions in
4981 resolve_address_of_overloaded_function (called by
4982 instantiate_type). It is possible that the call succeeded by
4983 converting &B::I to &D::I (where B is a base of D), so we need
4984 to reject this conversion here.
4986 Actually, even if there was a way to disable standard conversions,
4987 it would still be better to reject them here so that we can
4988 provide a superior diagnostic. */
4989 if (!same_type_p (TREE_TYPE (expr), type))
4991 /* Make sure we are just one standard conversion off. */
4992 gcc_assert (can_convert (type, TREE_TYPE (expr)));
4993 error ("%qE is not a valid template argument for type %qT "
4994 "because it is of type %qT", expr, type,
4996 inform (input_location, "standard conversions are not allowed in this context");
5000 /* [temp.arg.nontype]/5, bullet 7
5002 For a non-type template-parameter of type pointer to data member,
5003 qualification conversions (_conv.qual_) are applied. */
5004 else if (TYPE_PTRMEM_P (type))
5006 expr = perform_qualification_conversions (type, expr);
5007 if (expr == error_mark_node)
5010 /* A template non-type parameter must be one of the above. */
5014 /* Sanity check: did we actually convert the argument to the
5016 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
5020 /* Subroutine of coerce_template_template_parms, which returns 1 if
5021 PARM_PARM and ARG_PARM match using the rule for the template
5022 parameters of template template parameters. Both PARM and ARG are
5023 template parameters; the rest of the arguments are the same as for
5024 coerce_template_template_parms.
5027 coerce_template_template_parm (tree parm,
5029 tsubst_flags_t complain,
5033 if (arg == NULL_TREE || arg == error_mark_node
5034 || parm == NULL_TREE || parm == error_mark_node)
5037 if (TREE_CODE (arg) != TREE_CODE (parm))
5040 switch (TREE_CODE (parm))
5043 /* We encounter instantiations of templates like
5044 template <template <template <class> class> class TT>
5047 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5048 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5050 if (!coerce_template_template_parms
5051 (parmparm, argparm, complain, in_decl, outer_args))
5057 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
5058 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5059 /* Argument is a parameter pack but parameter is not. */
5064 /* The tsubst call is used to handle cases such as
5066 template <int> class C {};
5067 template <class T, template <T> class TT> class D {};
5070 i.e. the parameter list of TT depends on earlier parameters. */
5071 if (!uses_template_parms (TREE_TYPE (arg))
5073 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
5077 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
5078 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5079 /* Argument is a parameter pack but parameter is not. */
5092 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
5093 template template parameters. Both PARM_PARMS and ARG_PARMS are
5094 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
5097 Consider the example:
5098 template <class T> class A;
5099 template<template <class U> class TT> class B;
5101 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
5102 the parameters to A, and OUTER_ARGS contains A. */
5105 coerce_template_template_parms (tree parm_parms,
5107 tsubst_flags_t complain,
5111 int nparms, nargs, i;
5115 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
5116 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
5118 nparms = TREE_VEC_LENGTH (parm_parms);
5119 nargs = TREE_VEC_LENGTH (arg_parms);
5121 /* Determine whether we have a parameter pack at the end of the
5122 template template parameter's template parameter list. */
5123 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
5125 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
5127 if (parm == error_mark_node)
5130 switch (TREE_CODE (parm))
5134 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5139 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5149 && !(variadic_p && nargs >= nparms - 1))
5152 /* Check all of the template parameters except the parameter pack at
5153 the end (if any). */
5154 for (i = 0; i < nparms - variadic_p; ++i)
5156 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
5157 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5160 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5161 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5163 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5171 /* Check each of the template parameters in the template
5172 argument against the template parameter pack at the end of
5173 the template template parameter. */
5174 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
5177 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5179 for (; i < nargs; ++i)
5181 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5184 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5186 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5195 /* Verifies that the deduced template arguments (in TARGS) for the
5196 template template parameters (in TPARMS) represent valid bindings,
5197 by comparing the template parameter list of each template argument
5198 to the template parameter list of its corresponding template
5199 template parameter, in accordance with DR150. This
5200 routine can only be called after all template arguments have been
5201 deduced. It will return TRUE if all of the template template
5202 parameter bindings are okay, FALSE otherwise. */
5204 template_template_parm_bindings_ok_p (tree tparms, tree targs)
5206 int i, ntparms = TREE_VEC_LENGTH (tparms);
5209 /* We're dealing with template parms in this process. */
5210 ++processing_template_decl;
5212 targs = INNERMOST_TEMPLATE_ARGS (targs);
5214 for (i = 0; i < ntparms; ++i)
5216 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
5217 tree targ = TREE_VEC_ELT (targs, i);
5219 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
5221 tree packed_args = NULL_TREE;
5224 if (ARGUMENT_PACK_P (targ))
5226 /* Look inside the argument pack. */
5227 packed_args = ARGUMENT_PACK_ARGS (targ);
5228 len = TREE_VEC_LENGTH (packed_args);
5231 for (idx = 0; idx < len; ++idx)
5233 tree targ_parms = NULL_TREE;
5236 /* Extract the next argument from the argument
5238 targ = TREE_VEC_ELT (packed_args, idx);
5240 if (PACK_EXPANSION_P (targ))
5241 /* Look at the pattern of the pack expansion. */
5242 targ = PACK_EXPANSION_PATTERN (targ);
5244 /* Extract the template parameters from the template
5246 if (TREE_CODE (targ) == TEMPLATE_DECL)
5247 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
5248 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
5249 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
5251 /* Verify that we can coerce the template template
5252 parameters from the template argument to the template
5253 parameter. This requires an exact match. */
5255 && !coerce_template_template_parms
5256 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
5271 --processing_template_decl;
5275 /* Convert the indicated template ARG as necessary to match the
5276 indicated template PARM. Returns the converted ARG, or
5277 error_mark_node if the conversion was unsuccessful. Error and
5278 warning messages are issued under control of COMPLAIN. This
5279 conversion is for the Ith parameter in the parameter list. ARGS is
5280 the full set of template arguments deduced so far. */
5283 convert_template_argument (tree parm,
5286 tsubst_flags_t complain,
5292 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
5294 if (TREE_CODE (arg) == TREE_LIST
5295 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
5297 /* The template argument was the name of some
5298 member function. That's usually
5299 invalid, but static members are OK. In any
5300 case, grab the underlying fields/functions
5301 and issue an error later if required. */
5302 orig_arg = TREE_VALUE (arg);
5303 TREE_TYPE (arg) = unknown_type_node;
5308 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
5309 requires_type = (TREE_CODE (parm) == TYPE_DECL
5310 || requires_tmpl_type);
5312 /* When determining whether an argument pack expansion is a template,
5313 look at the pattern. */
5314 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
5315 arg = PACK_EXPANSION_PATTERN (arg);
5318 ((TREE_CODE (arg) == TEMPLATE_DECL
5319 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
5320 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5321 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
5324 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5325 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
5326 arg = TYPE_STUB_DECL (arg);
5328 is_type = TYPE_P (arg) || is_tmpl_type;
5330 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
5331 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
5333 permerror (input_location, "to refer to a type member of a template parameter, "
5334 "use %<typename %E%>", orig_arg);
5336 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
5337 TREE_OPERAND (arg, 1),
5339 complain & tf_error);
5343 if (is_type != requires_type)
5347 if (complain & tf_error)
5349 error ("type/value mismatch at argument %d in template "
5350 "parameter list for %qD",
5353 error (" expected a constant of type %qT, got %qT",
5355 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
5356 else if (requires_tmpl_type)
5357 error (" expected a class template, got %qE", orig_arg);
5359 error (" expected a type, got %qE", orig_arg);
5362 return error_mark_node;
5364 if (is_tmpl_type ^ requires_tmpl_type)
5366 if (in_decl && (complain & tf_error))
5368 error ("type/value mismatch at argument %d in template "
5369 "parameter list for %qD",
5372 error (" expected a type, got %qT", DECL_NAME (arg));
5374 error (" expected a class template, got %qT", orig_arg);
5376 return error_mark_node;
5381 if (requires_tmpl_type)
5383 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
5384 /* The number of argument required is not known yet.
5385 Just accept it for now. */
5386 val = TREE_TYPE (arg);
5389 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5392 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5394 if (coerce_template_template_parms (parmparm, argparm,
5400 /* TEMPLATE_TEMPLATE_PARM node is preferred over
5402 if (val != error_mark_node)
5404 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
5405 val = TREE_TYPE (val);
5406 else if (TREE_CODE (val) == TYPE_PACK_EXPANSION
5407 && DECL_TEMPLATE_TEMPLATE_PARM_P (arg))
5409 val = TREE_TYPE (arg);
5410 val = make_pack_expansion (val);
5416 if (in_decl && (complain & tf_error))
5418 error ("type/value mismatch at argument %d in "
5419 "template parameter list for %qD",
5421 error (" expected a template of type %qD, got %qD",
5425 val = error_mark_node;
5431 /* We only form one instance of each template specialization.
5432 Therefore, if we use a non-canonical variant (i.e., a
5433 typedef), any future messages referring to the type will use
5434 the typedef, which is confusing if those future uses do not
5435 themselves also use the typedef. */
5437 val = strip_typedefs (val);
5441 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
5443 if (invalid_nontype_parm_type_p (t, complain))
5444 return error_mark_node;
5446 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
5448 if (same_type_p (t, TREE_TYPE (orig_arg)))
5452 /* Not sure if this is reachable, but it doesn't hurt
5454 error ("type mismatch in nontype parameter pack");
5455 val = error_mark_node;
5458 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
5459 /* We used to call digest_init here. However, digest_init
5460 will report errors, which we don't want when complain
5461 is zero. More importantly, digest_init will try too
5462 hard to convert things: for example, `0' should not be
5463 converted to pointer type at this point according to
5464 the standard. Accepting this is not merely an
5465 extension, since deciding whether or not these
5466 conversions can occur is part of determining which
5467 function template to call, or whether a given explicit
5468 argument specification is valid. */
5469 val = convert_nontype_argument (t, orig_arg);
5473 if (val == NULL_TREE)
5474 val = error_mark_node;
5475 else if (val == error_mark_node && (complain & tf_error))
5476 error ("could not convert template argument %qE to %qT", orig_arg, t);
5482 /* Coerces the remaining template arguments in INNER_ARGS (from
5483 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
5484 Returns the coerced argument pack. PARM_IDX is the position of this
5485 parameter in the template parameter list. ARGS is the original
5486 template argument list. */
5488 coerce_template_parameter_pack (tree parms,
5496 tsubst_flags_t complain)
5498 tree parm = TREE_VEC_ELT (parms, parm_idx);
5499 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5502 tree packed_types = NULL_TREE;
5504 if (arg_idx > nargs)
5507 packed_args = make_tree_vec (nargs - arg_idx);
5509 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
5510 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
5512 /* When the template parameter is a non-type template
5513 parameter pack whose type uses parameter packs, we need
5514 to look at each of the template arguments
5515 separately. Build a vector of the types for these
5516 non-type template parameters in PACKED_TYPES. */
5518 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
5519 packed_types = tsubst_pack_expansion (expansion, args,
5522 if (packed_types == error_mark_node)
5523 return error_mark_node;
5525 /* Check that we have the right number of arguments. */
5527 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
5528 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
5531 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
5532 error ("wrong number of template arguments (%d, should be %d)",
5533 nargs, needed_parms);
5534 return error_mark_node;
5537 /* If we aren't able to check the actual arguments now
5538 (because they haven't been expanded yet), we can at least
5539 verify that all of the types used for the non-type
5540 template parameter pack are, in fact, valid for non-type
5541 template parameters. */
5543 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
5545 int j, len = TREE_VEC_LENGTH (packed_types);
5546 for (j = 0; j < len; ++j)
5548 tree t = TREE_VEC_ELT (packed_types, j);
5549 if (invalid_nontype_parm_type_p (t, complain))
5550 return error_mark_node;
5555 /* Convert the remaining arguments, which will be a part of the
5556 parameter pack "parm". */
5557 for (; arg_idx < nargs; ++arg_idx)
5559 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
5560 tree actual_parm = TREE_VALUE (parm);
5562 if (packed_types && !PACK_EXPANSION_P (arg))
5564 /* When we have a vector of types (corresponding to the
5565 non-type template parameter pack that uses parameter
5566 packs in its type, as mention above), and the
5567 argument is not an expansion (which expands to a
5568 currently unknown number of arguments), clone the
5569 parm and give it the next type in PACKED_TYPES. */
5570 actual_parm = copy_node (actual_parm);
5571 TREE_TYPE (actual_parm) =
5572 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
5575 if (arg != error_mark_node)
5576 arg = convert_template_argument (actual_parm,
5577 arg, new_args, complain, parm_idx,
5579 if (arg == error_mark_node)
5581 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
5584 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
5585 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
5586 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
5589 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
5590 TREE_TYPE (argument_pack)
5591 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
5592 TREE_CONSTANT (argument_pack) = 1;
5595 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
5596 return argument_pack;
5599 /* Convert all template arguments to their appropriate types, and
5600 return a vector containing the innermost resulting template
5601 arguments. If any error occurs, return error_mark_node. Error and
5602 warning messages are issued under control of COMPLAIN.
5604 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
5605 for arguments not specified in ARGS. Otherwise, if
5606 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
5607 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
5608 USE_DEFAULT_ARGS is false, then all arguments must be specified in
5612 coerce_template_parms (tree parms,
5615 tsubst_flags_t complain,
5616 bool require_all_args,
5617 bool use_default_args)
5619 int nparms, nargs, parm_idx, arg_idx, lost = 0;
5622 tree new_inner_args;
5623 int saved_unevaluated_operand;
5624 int saved_inhibit_evaluation_warnings;
5626 /* When used as a boolean value, indicates whether this is a
5627 variadic template parameter list. Since it's an int, we can also
5628 subtract it from nparms to get the number of non-variadic
5632 nparms = TREE_VEC_LENGTH (parms);
5634 /* Determine if there are any parameter packs. */
5635 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
5637 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
5638 if (template_parameter_pack_p (tparm))
5642 inner_args = INNERMOST_TEMPLATE_ARGS (args);
5643 /* If there are 0 or 1 parameter packs, we need to expand any argument
5644 packs so that we can deduce a parameter pack from some non-packed args
5645 followed by an argument pack, as in variadic85.C. If there are more
5646 than that, we need to leave argument packs intact so the arguments are
5647 assigned to the right parameter packs. This should only happen when
5648 dealing with a nested class inside a partial specialization of a class
5649 template, as in variadic92.C. */
5650 if (variadic_p <= 1)
5651 inner_args = expand_template_argument_pack (inner_args);
5653 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5654 if ((nargs > nparms && !variadic_p)
5655 || (nargs < nparms - variadic_p
5657 && (!use_default_args
5658 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
5659 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
5661 if (complain & tf_error)
5663 const char *or_more = "";
5666 or_more = " or more";
5670 error ("wrong number of template arguments (%d, should be %d%s)",
5671 nargs, nparms, or_more);
5674 error ("provided for %q+D", in_decl);
5677 return error_mark_node;
5680 /* We need to evaluate the template arguments, even though this
5681 template-id may be nested within a "sizeof". */
5682 saved_unevaluated_operand = cp_unevaluated_operand;
5683 cp_unevaluated_operand = 0;
5684 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
5685 c_inhibit_evaluation_warnings = 0;
5686 new_inner_args = make_tree_vec (nparms);
5687 new_args = add_outermost_template_args (args, new_inner_args);
5688 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
5693 /* Get the Ith template parameter. */
5694 parm = TREE_VEC_ELT (parms, parm_idx);
5696 if (parm == error_mark_node)
5698 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
5702 /* Calculate the next argument. */
5703 if (arg_idx < nargs)
5704 arg = TREE_VEC_ELT (inner_args, arg_idx);
5708 if (template_parameter_pack_p (TREE_VALUE (parm))
5709 && !(arg && ARGUMENT_PACK_P (arg)))
5711 /* All remaining arguments will be placed in the
5712 template parameter pack PARM. */
5713 arg = coerce_template_parameter_pack (parms, parm_idx, args,
5714 inner_args, arg_idx,
5718 /* Store this argument. */
5719 if (arg == error_mark_node)
5721 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
5723 /* We are done with all of the arguments. */
5730 if (PACK_EXPANSION_P (arg))
5732 if (complain & tf_error)
5734 /* FIXME this restriction was removed by N2555; see
5736 /* If ARG is a pack expansion, but PARM is not a
5737 template parameter pack (if it were, we would have
5738 handled it above), we're trying to expand into a
5739 fixed-length argument list. */
5740 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
5741 sorry ("cannot expand %<%E%> into a fixed-length "
5742 "argument list", arg);
5744 sorry ("cannot expand %<%T%> into a fixed-length "
5745 "argument list", arg);
5747 return error_mark_node;
5750 else if (require_all_args)
5751 /* There must be a default arg in this case. */
5752 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
5757 if (arg == error_mark_node)
5759 if (complain & tf_error)
5760 error ("template argument %d is invalid", arg_idx + 1);
5763 /* This only occurs if there was an error in the template
5764 parameter list itself (which we would already have
5765 reported) that we are trying to recover from, e.g., a class
5766 template with a parameter list such as
5767 template<typename..., typename>. */
5768 return error_mark_node;
5770 arg = convert_template_argument (TREE_VALUE (parm),
5771 arg, new_args, complain,
5774 if (arg == error_mark_node)
5776 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
5778 cp_unevaluated_operand = saved_unevaluated_operand;
5779 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
5782 return error_mark_node;
5784 return new_inner_args;
5787 /* Returns 1 if template args OT and NT are equivalent. */
5790 template_args_equal (tree ot, tree nt)
5795 if (TREE_CODE (nt) == TREE_VEC)
5796 /* For member templates */
5797 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
5798 else if (PACK_EXPANSION_P (ot))
5799 return PACK_EXPANSION_P (nt)
5800 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
5801 PACK_EXPANSION_PATTERN (nt));
5802 else if (ARGUMENT_PACK_P (ot))
5807 if (!ARGUMENT_PACK_P (nt))
5810 opack = ARGUMENT_PACK_ARGS (ot);
5811 npack = ARGUMENT_PACK_ARGS (nt);
5812 len = TREE_VEC_LENGTH (opack);
5813 if (TREE_VEC_LENGTH (npack) != len)
5815 for (i = 0; i < len; ++i)
5816 if (!template_args_equal (TREE_VEC_ELT (opack, i),
5817 TREE_VEC_ELT (npack, i)))
5821 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
5823 /* We get here probably because we are in the middle of substituting
5824 into the pattern of a pack expansion. In that case the
5825 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
5826 interested in. So we want to use the initial pack argument for
5828 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
5829 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
5830 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
5831 return template_args_equal (ot, nt);
5833 else if (TYPE_P (nt))
5834 return TYPE_P (ot) && same_type_p (ot, nt);
5835 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
5838 return cp_tree_equal (ot, nt);
5841 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
5842 of template arguments. Returns 0 otherwise. */
5845 comp_template_args (tree oldargs, tree newargs)
5849 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
5852 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
5854 tree nt = TREE_VEC_ELT (newargs, i);
5855 tree ot = TREE_VEC_ELT (oldargs, i);
5857 if (! template_args_equal (ot, nt))
5864 add_pending_template (tree d)
5866 tree ti = (TYPE_P (d)
5867 ? CLASSTYPE_TEMPLATE_INFO (d)
5868 : DECL_TEMPLATE_INFO (d));
5869 struct pending_template *pt;
5872 if (TI_PENDING_TEMPLATE_FLAG (ti))
5875 /* We are called both from instantiate_decl, where we've already had a
5876 tinst_level pushed, and instantiate_template, where we haven't.
5878 level = !current_tinst_level || current_tinst_level->decl != d;
5881 push_tinst_level (d);
5883 pt = GGC_NEW (struct pending_template);
5885 pt->tinst = current_tinst_level;
5886 if (last_pending_template)
5887 last_pending_template->next = pt;
5889 pending_templates = pt;
5891 last_pending_template = pt;
5893 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
5900 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
5901 ARGLIST. Valid choices for FNS are given in the cp-tree.def
5902 documentation for TEMPLATE_ID_EXPR. */
5905 lookup_template_function (tree fns, tree arglist)
5909 if (fns == error_mark_node || arglist == error_mark_node)
5910 return error_mark_node;
5912 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
5913 gcc_assert (fns && (is_overloaded_fn (fns)
5914 || TREE_CODE (fns) == IDENTIFIER_NODE));
5916 if (BASELINK_P (fns))
5918 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
5920 BASELINK_FUNCTIONS (fns),
5925 type = TREE_TYPE (fns);
5926 if (TREE_CODE (fns) == OVERLOAD || !type)
5927 type = unknown_type_node;
5929 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
5932 /* Within the scope of a template class S<T>, the name S gets bound
5933 (in build_self_reference) to a TYPE_DECL for the class, not a
5934 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
5935 or one of its enclosing classes, and that type is a template,
5936 return the associated TEMPLATE_DECL. Otherwise, the original
5937 DECL is returned. */
5940 maybe_get_template_decl_from_type_decl (tree decl)
5942 return (decl != NULL_TREE
5943 && TREE_CODE (decl) == TYPE_DECL
5944 && DECL_ARTIFICIAL (decl)
5945 && CLASS_TYPE_P (TREE_TYPE (decl))
5946 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
5947 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
5950 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
5951 parameters, find the desired type.
5953 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
5955 IN_DECL, if non-NULL, is the template declaration we are trying to
5958 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
5959 the class we are looking up.
5961 Issue error and warning messages under control of COMPLAIN.
5963 If the template class is really a local class in a template
5964 function, then the FUNCTION_CONTEXT is the function in which it is
5967 ??? Note that this function is currently called *twice* for each
5968 template-id: the first time from the parser, while creating the
5969 incomplete type (finish_template_type), and the second type during the
5970 real instantiation (instantiate_template_class). This is surely something
5971 that we want to avoid. It also causes some problems with argument
5972 coercion (see convert_nontype_argument for more information on this). */
5975 lookup_template_class (tree d1,
5980 tsubst_flags_t complain)
5982 tree templ = NULL_TREE, parmlist;
5989 timevar_push (TV_NAME_LOOKUP);
5991 if (TREE_CODE (d1) == IDENTIFIER_NODE)
5993 tree value = innermost_non_namespace_value (d1);
5994 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
5999 push_decl_namespace (context);
6000 templ = lookup_name (d1);
6001 templ = maybe_get_template_decl_from_type_decl (templ);
6003 pop_decl_namespace ();
6006 context = DECL_CONTEXT (templ);
6008 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
6010 tree type = TREE_TYPE (d1);
6012 /* If we are declaring a constructor, say A<T>::A<T>, we will get
6013 an implicit typename for the second A. Deal with it. */
6014 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
6015 type = TREE_TYPE (type);
6017 if (CLASSTYPE_TEMPLATE_INFO (type))
6019 templ = CLASSTYPE_TI_TEMPLATE (type);
6020 d1 = DECL_NAME (templ);
6023 else if (TREE_CODE (d1) == ENUMERAL_TYPE
6024 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
6026 templ = TYPE_TI_TEMPLATE (d1);
6027 d1 = DECL_NAME (templ);
6029 else if (TREE_CODE (d1) == TEMPLATE_DECL
6030 && DECL_TEMPLATE_RESULT (d1)
6031 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
6034 d1 = DECL_NAME (templ);
6035 context = DECL_CONTEXT (templ);
6038 /* Issue an error message if we didn't find a template. */
6041 if (complain & tf_error)
6042 error ("%qT is not a template", d1);
6043 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6046 if (TREE_CODE (templ) != TEMPLATE_DECL
6047 /* Make sure it's a user visible template, if it was named by
6049 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
6050 && !PRIMARY_TEMPLATE_P (templ)))
6052 if (complain & tf_error)
6054 error ("non-template type %qT used as a template", d1);
6056 error ("for template declaration %q+D", in_decl);
6058 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6061 complain &= ~tf_user;
6063 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
6065 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
6066 template arguments */
6072 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
6074 /* Consider an example where a template template parameter declared as
6076 template <class T, class U = std::allocator<T> > class TT
6078 The template parameter level of T and U are one level larger than
6079 of TT. To proper process the default argument of U, say when an
6080 instantiation `TT<int>' is seen, we need to build the full
6081 arguments containing {int} as the innermost level. Outer levels,
6082 available when not appearing as default template argument, can be
6083 obtained from the arguments of the enclosing template.
6085 Suppose that TT is later substituted with std::vector. The above
6086 instantiation is `TT<int, std::allocator<T> >' with TT at
6087 level 1, and T at level 2, while the template arguments at level 1
6088 becomes {std::vector} and the inner level 2 is {int}. */
6090 outer = DECL_CONTEXT (templ);
6092 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
6093 else if (current_template_parms)
6094 /* This is an argument of the current template, so we haven't set
6095 DECL_CONTEXT yet. */
6096 outer = current_template_args ();
6099 arglist = add_to_template_args (outer, arglist);
6101 arglist2 = coerce_template_parms (parmlist, arglist, templ,
6103 /*require_all_args=*/true,
6104 /*use_default_args=*/true);
6105 if (arglist2 == error_mark_node
6106 || (!uses_template_parms (arglist2)
6107 && check_instantiated_args (templ, arglist2, complain)))
6108 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6110 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
6111 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
6115 tree template_type = TREE_TYPE (templ);
6118 tree found = NULL_TREE;
6121 int is_partial_instantiation;
6123 gen_tmpl = most_general_template (templ);
6124 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
6125 parm_depth = TMPL_PARMS_DEPTH (parmlist);
6126 arg_depth = TMPL_ARGS_DEPTH (arglist);
6128 if (arg_depth == 1 && parm_depth > 1)
6130 /* We've been given an incomplete set of template arguments.
6133 template <class T> struct S1 {
6134 template <class U> struct S2 {};
6135 template <class U> struct S2<U*> {};
6138 we will be called with an ARGLIST of `U*', but the
6139 TEMPLATE will be `template <class T> template
6140 <class U> struct S1<T>::S2'. We must fill in the missing
6143 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
6145 arg_depth = TMPL_ARGS_DEPTH (arglist);
6148 /* Now we should have enough arguments. */
6149 gcc_assert (parm_depth == arg_depth);
6151 /* From here on, we're only interested in the most general
6154 /* Calculate the BOUND_ARGS. These will be the args that are
6155 actually tsubst'd into the definition to create the
6159 /* We have multiple levels of arguments to coerce, at once. */
6161 int saved_depth = TMPL_ARGS_DEPTH (arglist);
6163 tree bound_args = make_tree_vec (parm_depth);
6165 for (i = saved_depth,
6166 t = DECL_TEMPLATE_PARMS (gen_tmpl);
6167 i > 0 && t != NULL_TREE;
6168 --i, t = TREE_CHAIN (t))
6170 tree a = coerce_template_parms (TREE_VALUE (t),
6173 /*require_all_args=*/true,
6174 /*use_default_args=*/true);
6176 /* Don't process further if one of the levels fails. */
6177 if (a == error_mark_node)
6179 /* Restore the ARGLIST to its full size. */
6180 TREE_VEC_LENGTH (arglist) = saved_depth;
6181 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6184 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
6186 /* We temporarily reduce the length of the ARGLIST so
6187 that coerce_template_parms will see only the arguments
6188 corresponding to the template parameters it is
6190 TREE_VEC_LENGTH (arglist)--;
6193 /* Restore the ARGLIST to its full size. */
6194 TREE_VEC_LENGTH (arglist) = saved_depth;
6196 arglist = bound_args;
6200 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
6201 INNERMOST_TEMPLATE_ARGS (arglist),
6204 /*require_all_args=*/true,
6205 /*use_default_args=*/true);
6207 if (arglist == error_mark_node)
6208 /* We were unable to bind the arguments. */
6209 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6211 /* In the scope of a template class, explicit references to the
6212 template class refer to the type of the template, not any
6213 instantiation of it. For example, in:
6215 template <class T> class C { void f(C<T>); }
6217 the `C<T>' is just the same as `C'. Outside of the
6218 class, however, such a reference is an instantiation. */
6220 || !PRIMARY_TEMPLATE_P (gen_tmpl)
6221 || currently_open_class (template_type))
6222 /* comp_template_args is expensive, check it last. */
6223 && comp_template_args (TYPE_TI_ARGS (template_type),
6225 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, template_type);
6227 /* If we already have this specialization, return it. */
6228 elt.tmpl = gen_tmpl;
6230 hash = hash_specialization (&elt);
6231 entry = (spec_entry *) htab_find_with_hash (type_specializations,
6235 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, entry->spec);
6237 /* This type is a "partial instantiation" if any of the template
6238 arguments still involve template parameters. Note that we set
6239 IS_PARTIAL_INSTANTIATION for partial specializations as
6241 is_partial_instantiation = uses_template_parms (arglist);
6243 /* If the deduced arguments are invalid, then the binding
6245 if (!is_partial_instantiation
6246 && check_instantiated_args (gen_tmpl,
6247 INNERMOST_TEMPLATE_ARGS (arglist),
6249 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6251 if (!is_partial_instantiation
6252 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6253 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
6254 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
6256 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
6257 DECL_NAME (gen_tmpl),
6258 /*tag_scope=*/ts_global);
6259 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
6262 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
6265 context = global_namespace;
6267 /* Create the type. */
6268 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
6270 if (!is_partial_instantiation)
6272 set_current_access_from_decl (TYPE_NAME (template_type));
6273 t = start_enum (TYPE_IDENTIFIER (template_type),
6274 tsubst (ENUM_UNDERLYING_TYPE (template_type),
6275 arglist, complain, in_decl),
6276 SCOPED_ENUM_P (template_type));
6280 /* We don't want to call start_enum for this type, since
6281 the values for the enumeration constants may involve
6282 template parameters. And, no one should be interested
6283 in the enumeration constants for such a type. */
6284 t = cxx_make_type (ENUMERAL_TYPE);
6285 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
6290 t = make_class_type (TREE_CODE (template_type));
6291 CLASSTYPE_DECLARED_CLASS (t)
6292 = CLASSTYPE_DECLARED_CLASS (template_type);
6293 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
6294 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
6296 /* A local class. Make sure the decl gets registered properly. */
6297 if (context == current_function_decl)
6298 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
6300 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
6301 /* This instantiation is another name for the primary
6302 template type. Set the TYPE_CANONICAL field
6304 TYPE_CANONICAL (t) = template_type;
6305 else if (any_template_arguments_need_structural_equality_p (arglist))
6306 /* Some of the template arguments require structural
6307 equality testing, so this template class requires
6308 structural equality testing. */
6309 SET_TYPE_STRUCTURAL_EQUALITY (t);
6312 /* If we called start_enum or pushtag above, this information
6313 will already be set up. */
6316 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
6318 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
6319 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
6320 TYPE_STUB_DECL (t) = type_decl;
6321 DECL_SOURCE_LOCATION (type_decl)
6322 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
6325 type_decl = TYPE_NAME (t);
6327 TREE_PRIVATE (type_decl)
6328 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
6329 TREE_PROTECTED (type_decl)
6330 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
6331 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
6333 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
6334 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
6337 /* Set up the template information. We have to figure out which
6338 template is the immediate parent if this is a full
6340 if (parm_depth == 1 || is_partial_instantiation
6341 || !PRIMARY_TEMPLATE_P (gen_tmpl))
6342 /* This case is easy; there are no member templates involved. */
6346 /* This is a full instantiation of a member template. Find
6347 the partial instantiation of which this is an instance. */
6349 /* Temporarily reduce by one the number of levels in the ARGLIST
6350 so as to avoid comparing the last set of arguments. */
6351 TREE_VEC_LENGTH (arglist)--;
6352 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
6353 TREE_VEC_LENGTH (arglist)++;
6354 found = CLASSTYPE_TI_TEMPLATE (found);
6357 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
6360 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
6361 &elt, hash, INSERT);
6362 *slot = GGC_NEW (spec_entry);
6365 /* Note this use of the partial instantiation so we can check it
6366 later in maybe_process_partial_specialization. */
6367 DECL_TEMPLATE_INSTANTIATIONS (templ)
6368 = tree_cons (arglist, t,
6369 DECL_TEMPLATE_INSTANTIATIONS (templ));
6371 if (TREE_CODE (t) == ENUMERAL_TYPE
6372 && !is_partial_instantiation)
6373 /* Now that the type has been registered on the instantiations
6374 list, we set up the enumerators. Because the enumeration
6375 constants may involve the enumeration type itself, we make
6376 sure to register the type first, and then create the
6377 constants. That way, doing tsubst_expr for the enumeration
6378 constants won't result in recursive calls here; we'll find
6379 the instantiation and exit above. */
6380 tsubst_enum (template_type, t, arglist);
6382 if (is_partial_instantiation)
6383 /* If the type makes use of template parameters, the
6384 code that generates debugging information will crash. */
6385 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
6387 /* Possibly limit visibility based on template args. */
6388 TREE_PUBLIC (type_decl) = 1;
6389 determine_visibility (type_decl);
6391 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
6393 timevar_pop (TV_NAME_LOOKUP);
6400 /* True when we should also visit template parameters that occur in
6401 non-deduced contexts. */
6402 bool include_nondeduced_p;
6403 struct pointer_set_t *visited;
6406 /* Called from for_each_template_parm via walk_tree. */
6409 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
6412 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
6413 tree_fn_t fn = pfd->fn;
6414 void *data = pfd->data;
6417 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
6418 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
6419 pfd->include_nondeduced_p))
6420 return error_mark_node;
6422 switch (TREE_CODE (t))
6425 if (TYPE_PTRMEMFUNC_P (t))
6431 if (!TYPE_TEMPLATE_INFO (t))
6433 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
6434 fn, data, pfd->visited,
6435 pfd->include_nondeduced_p))
6436 return error_mark_node;
6440 if (for_each_template_parm (TYPE_MIN_VALUE (t),
6441 fn, data, pfd->visited,
6442 pfd->include_nondeduced_p)
6443 || for_each_template_parm (TYPE_MAX_VALUE (t),
6444 fn, data, pfd->visited,
6445 pfd->include_nondeduced_p))
6446 return error_mark_node;
6450 /* Since we're not going to walk subtrees, we have to do this
6452 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
6453 pfd->visited, pfd->include_nondeduced_p))
6454 return error_mark_node;
6458 /* Check the return type. */
6459 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6460 pfd->include_nondeduced_p))
6461 return error_mark_node;
6463 /* Check the parameter types. Since default arguments are not
6464 instantiated until they are needed, the TYPE_ARG_TYPES may
6465 contain expressions that involve template parameters. But,
6466 no-one should be looking at them yet. And, once they're
6467 instantiated, they don't contain template parameters, so
6468 there's no point in looking at them then, either. */
6472 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
6473 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
6474 pfd->visited, pfd->include_nondeduced_p))
6475 return error_mark_node;
6477 /* Since we've already handled the TYPE_ARG_TYPES, we don't
6478 want walk_tree walking into them itself. */
6484 if (pfd->include_nondeduced_p
6485 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
6487 pfd->include_nondeduced_p))
6488 return error_mark_node;
6493 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
6494 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
6495 pfd->visited, pfd->include_nondeduced_p))
6496 return error_mark_node;
6501 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
6502 && for_each_template_parm (DECL_INITIAL (t), fn, data,
6503 pfd->visited, pfd->include_nondeduced_p))
6504 return error_mark_node;
6505 if (DECL_CONTEXT (t)
6506 && pfd->include_nondeduced_p
6507 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
6508 pfd->visited, pfd->include_nondeduced_p))
6509 return error_mark_node;
6512 case BOUND_TEMPLATE_TEMPLATE_PARM:
6513 /* Record template parameters such as `T' inside `TT<T>'. */
6514 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
6515 pfd->include_nondeduced_p))
6516 return error_mark_node;
6519 case TEMPLATE_TEMPLATE_PARM:
6520 case TEMPLATE_TYPE_PARM:
6521 case TEMPLATE_PARM_INDEX:
6522 if (fn && (*fn)(t, data))
6523 return error_mark_node;
6525 return error_mark_node;
6529 /* A template template parameter is encountered. */
6530 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
6531 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6532 pfd->include_nondeduced_p))
6533 return error_mark_node;
6535 /* Already substituted template template parameter */
6541 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
6543 pfd->include_nondeduced_p))
6544 return error_mark_node;
6548 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
6549 && pfd->include_nondeduced_p
6550 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
6551 (TREE_TYPE (t)), fn, data,
6552 pfd->visited, pfd->include_nondeduced_p))
6553 return error_mark_node;
6558 /* If there's no type, then this thing must be some expression
6559 involving template parameters. */
6560 if (!fn && !TREE_TYPE (t))
6561 return error_mark_node;
6566 case REINTERPRET_CAST_EXPR:
6567 case CONST_CAST_EXPR:
6568 case STATIC_CAST_EXPR:
6569 case DYNAMIC_CAST_EXPR:
6573 case PSEUDO_DTOR_EXPR:
6575 return error_mark_node;
6582 /* We didn't find any template parameters we liked. */
6586 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
6587 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
6588 call FN with the parameter and the DATA.
6589 If FN returns nonzero, the iteration is terminated, and
6590 for_each_template_parm returns 1. Otherwise, the iteration
6591 continues. If FN never returns a nonzero value, the value
6592 returned by for_each_template_parm is 0. If FN is NULL, it is
6593 considered to be the function which always returns 1.
6595 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
6596 parameters that occur in non-deduced contexts. When false, only
6597 visits those template parameters that can be deduced. */
6600 for_each_template_parm (tree t, tree_fn_t fn, void* data,
6601 struct pointer_set_t *visited,
6602 bool include_nondeduced_p)
6604 struct pair_fn_data pfd;
6610 pfd.include_nondeduced_p = include_nondeduced_p;
6612 /* Walk the tree. (Conceptually, we would like to walk without
6613 duplicates, but for_each_template_parm_r recursively calls
6614 for_each_template_parm, so we would need to reorganize a fair
6615 bit to use walk_tree_without_duplicates, so we keep our own
6618 pfd.visited = visited;
6620 pfd.visited = pointer_set_create ();
6621 result = cp_walk_tree (&t,
6622 for_each_template_parm_r,
6624 pfd.visited) != NULL_TREE;
6629 pointer_set_destroy (pfd.visited);
6636 /* Returns true if T depends on any template parameter. */
6639 uses_template_parms (tree t)
6642 int saved_processing_template_decl;
6644 saved_processing_template_decl = processing_template_decl;
6645 if (!saved_processing_template_decl)
6646 processing_template_decl = 1;
6648 dependent_p = dependent_type_p (t);
6649 else if (TREE_CODE (t) == TREE_VEC)
6650 dependent_p = any_dependent_template_arguments_p (t);
6651 else if (TREE_CODE (t) == TREE_LIST)
6652 dependent_p = (uses_template_parms (TREE_VALUE (t))
6653 || uses_template_parms (TREE_CHAIN (t)));
6654 else if (TREE_CODE (t) == TYPE_DECL)
6655 dependent_p = dependent_type_p (TREE_TYPE (t));
6658 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
6659 || TREE_CODE (t) == OVERLOAD
6660 || TREE_CODE (t) == BASELINK
6661 || TREE_CODE (t) == IDENTIFIER_NODE
6662 || TREE_CODE (t) == TRAIT_EXPR
6663 || TREE_CODE (t) == CONSTRUCTOR
6664 || CONSTANT_CLASS_P (t))
6665 dependent_p = (type_dependent_expression_p (t)
6666 || value_dependent_expression_p (t));
6669 gcc_assert (t == error_mark_node);
6670 dependent_p = false;
6673 processing_template_decl = saved_processing_template_decl;
6678 /* Returns true if T depends on any template parameter with level LEVEL. */
6681 uses_template_parms_level (tree t, int level)
6683 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
6684 /*include_nondeduced_p=*/true);
6687 static int tinst_depth;
6688 extern int max_tinst_depth;
6689 #ifdef GATHER_STATISTICS
6692 static int tinst_level_tick;
6693 static int last_template_error_tick;
6695 /* We're starting to instantiate D; record the template instantiation context
6696 for diagnostics and to restore it later. */
6699 push_tinst_level (tree d)
6701 struct tinst_level *new_level;
6703 if (tinst_depth >= max_tinst_depth)
6705 /* If the instantiation in question still has unbound template parms,
6706 we don't really care if we can't instantiate it, so just return.
6707 This happens with base instantiation for implicit `typename'. */
6708 if (uses_template_parms (d))
6711 last_template_error_tick = tinst_level_tick;
6712 error ("template instantiation depth exceeds maximum of %d (use "
6713 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
6714 max_tinst_depth, d);
6716 print_instantiation_context ();
6721 new_level = GGC_NEW (struct tinst_level);
6722 new_level->decl = d;
6723 new_level->locus = input_location;
6724 new_level->in_system_header_p = in_system_header;
6725 new_level->next = current_tinst_level;
6726 current_tinst_level = new_level;
6729 #ifdef GATHER_STATISTICS
6730 if (tinst_depth > depth_reached)
6731 depth_reached = tinst_depth;
6738 /* We're done instantiating this template; return to the instantiation
6742 pop_tinst_level (void)
6744 /* Restore the filename and line number stashed away when we started
6745 this instantiation. */
6746 input_location = current_tinst_level->locus;
6747 current_tinst_level = current_tinst_level->next;
6752 /* We're instantiating a deferred template; restore the template
6753 instantiation context in which the instantiation was requested, which
6754 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
6757 reopen_tinst_level (struct tinst_level *level)
6759 struct tinst_level *t;
6762 for (t = level; t; t = t->next)
6765 current_tinst_level = level;
6770 /* Returns the TINST_LEVEL which gives the original instantiation
6773 struct tinst_level *
6774 outermost_tinst_level (void)
6776 struct tinst_level *level = current_tinst_level;
6779 level = level->next;
6783 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
6786 parameter_of_template_p (tree parm, tree templ)
6791 if (!parm || !templ)
6794 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
6795 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
6797 parms = DECL_TEMPLATE_PARMS (templ);
6798 parms = INNERMOST_TEMPLATE_PARMS (parms);
6800 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
6801 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
6807 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
6808 vector of template arguments, as for tsubst.
6810 Returns an appropriate tsubst'd friend declaration. */
6813 tsubst_friend_function (tree decl, tree args)
6817 if (TREE_CODE (decl) == FUNCTION_DECL
6818 && DECL_TEMPLATE_INSTANTIATION (decl)
6819 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
6820 /* This was a friend declared with an explicit template
6821 argument list, e.g.:
6825 to indicate that f was a template instantiation, not a new
6826 function declaration. Now, we have to figure out what
6827 instantiation of what template. */
6829 tree template_id, arglist, fns;
6832 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
6834 /* Friend functions are looked up in the containing namespace scope.
6835 We must enter that scope, to avoid finding member functions of the
6836 current class with same name. */
6837 push_nested_namespace (ns);
6838 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
6839 tf_warning_or_error, NULL_TREE,
6840 /*integral_constant_expression_p=*/false);
6841 pop_nested_namespace (ns);
6842 arglist = tsubst (DECL_TI_ARGS (decl), args,
6843 tf_warning_or_error, NULL_TREE);
6844 template_id = lookup_template_function (fns, arglist);
6846 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6847 tmpl = determine_specialization (template_id, new_friend,
6849 /*need_member_template=*/0,
6850 TREE_VEC_LENGTH (args),
6852 return instantiate_template (tmpl, new_args, tf_error);
6855 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6857 /* The NEW_FRIEND will look like an instantiation, to the
6858 compiler, but is not an instantiation from the point of view of
6859 the language. For example, we might have had:
6861 template <class T> struct S {
6862 template <class U> friend void f(T, U);
6865 Then, in S<int>, template <class U> void f(int, U) is not an
6866 instantiation of anything. */
6867 if (new_friend == error_mark_node)
6868 return error_mark_node;
6870 DECL_USE_TEMPLATE (new_friend) = 0;
6871 if (TREE_CODE (decl) == TEMPLATE_DECL)
6873 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
6874 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
6875 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
6878 /* The mangled name for the NEW_FRIEND is incorrect. The function
6879 is not a template instantiation and should not be mangled like
6880 one. Therefore, we forget the mangling here; we'll recompute it
6881 later if we need it. */
6882 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
6884 SET_DECL_RTL (new_friend, NULL_RTX);
6885 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
6888 if (DECL_NAMESPACE_SCOPE_P (new_friend))
6891 tree new_friend_template_info;
6892 tree new_friend_result_template_info;
6894 int new_friend_is_defn;
6896 /* We must save some information from NEW_FRIEND before calling
6897 duplicate decls since that function will free NEW_FRIEND if
6899 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
6900 new_friend_is_defn =
6901 (DECL_INITIAL (DECL_TEMPLATE_RESULT
6902 (template_for_substitution (new_friend)))
6904 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
6906 /* This declaration is a `primary' template. */
6907 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
6909 new_friend_result_template_info
6910 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
6913 new_friend_result_template_info = NULL_TREE;
6915 /* Make the init_value nonzero so pushdecl knows this is a defn. */
6916 if (new_friend_is_defn)
6917 DECL_INITIAL (new_friend) = error_mark_node;
6919 /* Inside pushdecl_namespace_level, we will push into the
6920 current namespace. However, the friend function should go
6921 into the namespace of the template. */
6922 ns = decl_namespace_context (new_friend);
6923 push_nested_namespace (ns);
6924 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
6925 pop_nested_namespace (ns);
6927 if (old_decl == error_mark_node)
6928 return error_mark_node;
6930 if (old_decl != new_friend)
6932 /* This new friend declaration matched an existing
6933 declaration. For example, given:
6935 template <class T> void f(T);
6936 template <class U> class C {
6937 template <class T> friend void f(T) {}
6940 the friend declaration actually provides the definition
6941 of `f', once C has been instantiated for some type. So,
6942 old_decl will be the out-of-class template declaration,
6943 while new_friend is the in-class definition.
6945 But, if `f' was called before this point, the
6946 instantiation of `f' will have DECL_TI_ARGS corresponding
6947 to `T' but not to `U', references to which might appear
6948 in the definition of `f'. Previously, the most general
6949 template for an instantiation of `f' was the out-of-class
6950 version; now it is the in-class version. Therefore, we
6951 run through all specialization of `f', adding to their
6952 DECL_TI_ARGS appropriately. In particular, they need a
6953 new set of outer arguments, corresponding to the
6954 arguments for this class instantiation.
6956 The same situation can arise with something like this:
6959 template <class T> class C {
6963 when `C<int>' is instantiated. Now, `f(int)' is defined
6966 if (!new_friend_is_defn)
6967 /* On the other hand, if the in-class declaration does
6968 *not* provide a definition, then we don't want to alter
6969 existing definitions. We can just leave everything
6974 tree new_template = TI_TEMPLATE (new_friend_template_info);
6975 tree new_args = TI_ARGS (new_friend_template_info);
6977 /* Overwrite whatever template info was there before, if
6978 any, with the new template information pertaining to
6980 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
6982 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
6983 /* We should have called reregister_specialization in
6985 gcc_assert (retrieve_specialization (new_template,
6992 /* Indicate that the old function template is a partial
6994 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
6995 = new_friend_result_template_info;
6997 gcc_assert (new_template
6998 == most_general_template (new_template));
6999 gcc_assert (new_template != old_decl);
7001 /* Reassign any specializations already in the hash table
7002 to the new more general template, and add the
7003 additional template args. */
7004 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
7008 tree spec = TREE_VALUE (t);
7011 elt.tmpl = old_decl;
7012 elt.args = DECL_TI_ARGS (spec);
7013 elt.spec = NULL_TREE;
7015 htab_remove_elt (decl_specializations, &elt);
7018 = add_outermost_template_args (new_args,
7019 DECL_TI_ARGS (spec));
7021 register_specialization
7022 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
7025 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
7029 /* The information from NEW_FRIEND has been merged into OLD_DECL
7030 by duplicate_decls. */
7031 new_friend = old_decl;
7036 tree context = DECL_CONTEXT (new_friend);
7040 template <class T> class C {
7041 template <class U> friend void C1<U>::f (); // case 1
7042 friend void C2<T>::f (); // case 2
7044 we only need to make sure CONTEXT is a complete type for
7045 case 2. To distinguish between the two cases, we note that
7046 CONTEXT of case 1 remains dependent type after tsubst while
7047 this isn't true for case 2. */
7048 ++processing_template_decl;
7049 dependent_p = dependent_type_p (context);
7050 --processing_template_decl;
7053 && !complete_type_or_else (context, NULL_TREE))
7054 return error_mark_node;
7056 if (COMPLETE_TYPE_P (context))
7058 /* Check to see that the declaration is really present, and,
7059 possibly obtain an improved declaration. */
7060 tree fn = check_classfn (context,
7061 new_friend, NULL_TREE);
7071 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
7072 template arguments, as for tsubst.
7074 Returns an appropriate tsubst'd friend type or error_mark_node on
7078 tsubst_friend_class (tree friend_tmpl, tree args)
7084 context = DECL_CONTEXT (friend_tmpl);
7088 if (TREE_CODE (context) == NAMESPACE_DECL)
7089 push_nested_namespace (context);
7091 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
7094 /* Look for a class template declaration. We look for hidden names
7095 because two friend declarations of the same template are the
7096 same. For example, in:
7099 template <typename> friend class F;
7101 template <typename> struct B {
7102 template <typename> friend class F;
7105 both F templates are the same. */
7106 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
7107 /*block_p=*/true, 0,
7108 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
7110 /* But, if we don't find one, it might be because we're in a
7111 situation like this:
7119 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
7120 for `S<int>', not the TEMPLATE_DECL. */
7121 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
7123 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
7124 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
7127 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
7129 /* The friend template has already been declared. Just
7130 check to see that the declarations match, and install any new
7131 default parameters. We must tsubst the default parameters,
7132 of course. We only need the innermost template parameters
7133 because that is all that redeclare_class_template will look
7135 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
7136 > TMPL_ARGS_DEPTH (args))
7139 location_t saved_input_location;
7140 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
7141 args, tf_warning_or_error);
7143 saved_input_location = input_location;
7144 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
7145 redeclare_class_template (TREE_TYPE (tmpl), parms);
7146 input_location = saved_input_location;
7150 friend_type = TREE_TYPE (tmpl);
7154 /* The friend template has not already been declared. In this
7155 case, the instantiation of the template class will cause the
7156 injection of this template into the global scope. */
7157 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7158 if (tmpl == error_mark_node)
7159 return error_mark_node;
7161 /* The new TMPL is not an instantiation of anything, so we
7162 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7163 the new type because that is supposed to be the corresponding
7164 template decl, i.e., TMPL. */
7165 DECL_USE_TEMPLATE (tmpl) = 0;
7166 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7167 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7168 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7169 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7171 /* Inject this template into the global scope. */
7172 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7177 if (TREE_CODE (context) == NAMESPACE_DECL)
7178 pop_nested_namespace (context);
7180 pop_nested_class ();
7186 /* Returns zero if TYPE cannot be completed later due to circularity.
7187 Otherwise returns one. */
7190 can_complete_type_without_circularity (tree type)
7192 if (type == NULL_TREE || type == error_mark_node)
7194 else if (COMPLETE_TYPE_P (type))
7196 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7197 return can_complete_type_without_circularity (TREE_TYPE (type));
7198 else if (CLASS_TYPE_P (type)
7199 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
7205 /* Apply any attributes which had to be deferred until instantiation
7206 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
7207 ARGS, COMPLAIN, IN_DECL are as tsubst. */
7210 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
7211 tree args, tsubst_flags_t complain, tree in_decl)
7213 tree last_dep = NULL_TREE;
7217 for (t = attributes; t; t = TREE_CHAIN (t))
7218 if (ATTR_IS_DEPENDENT (t))
7221 attributes = copy_list (attributes);
7225 if (DECL_P (*decl_p))
7227 if (TREE_TYPE (*decl_p) == error_mark_node)
7229 p = &DECL_ATTRIBUTES (*decl_p);
7232 p = &TYPE_ATTRIBUTES (*decl_p);
7236 tree late_attrs = NULL_TREE;
7237 tree *q = &late_attrs;
7239 for (*p = attributes; *p; )
7242 if (ATTR_IS_DEPENDENT (t))
7244 *p = TREE_CHAIN (t);
7245 TREE_CHAIN (t) = NULL_TREE;
7246 /* If the first attribute argument is an identifier, don't
7247 pass it through tsubst. Attributes like mode, format,
7248 cleanup and several target specific attributes expect it
7251 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
7252 && TREE_VALUE (TREE_VALUE (t))
7253 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
7254 == IDENTIFIER_NODE))
7257 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
7259 /*integral_constant_expression_p=*/false);
7260 if (chain != TREE_CHAIN (TREE_VALUE (t)))
7262 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
7267 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
7268 /*integral_constant_expression_p=*/false);
7270 q = &TREE_CHAIN (t);
7273 p = &TREE_CHAIN (t);
7276 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
7280 /* Perform (or defer) access check for typedefs that were referenced
7281 from within the template TMPL code.
7282 This is a subroutine of instantiate_template and instantiate_class_template.
7283 TMPL is the template to consider and TARGS is the list of arguments of
7287 perform_typedefs_access_check (tree tmpl, tree targs)
7292 || (!CLASS_TYPE_P (tmpl)
7293 && TREE_CODE (tmpl) != FUNCTION_DECL))
7296 for (t = get_types_needing_access_check (tmpl); t; t = TREE_CHAIN (t))
7298 tree type_decl = TREE_PURPOSE (t);
7299 tree type_scope = TREE_VALUE (t);
7301 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
7304 if (uses_template_parms (type_decl))
7305 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
7306 if (uses_template_parms (type_scope))
7307 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
7309 perform_or_defer_access_check (TYPE_BINFO (type_scope),
7310 type_decl, type_decl);
7315 instantiate_class_template (tree type)
7317 tree templ, args, pattern, t, member;
7322 if (type == error_mark_node)
7323 return error_mark_node;
7325 if (TYPE_BEING_DEFINED (type)
7326 || COMPLETE_TYPE_P (type)
7327 || dependent_type_p (type))
7330 /* Figure out which template is being instantiated. */
7331 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
7332 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7334 /* Determine what specialization of the original template to
7336 t = most_specialized_class (type, templ);
7337 if (t == error_mark_node)
7339 TYPE_BEING_DEFINED (type) = 1;
7340 return error_mark_node;
7344 /* This TYPE is actually an instantiation of a partial
7345 specialization. We replace the innermost set of ARGS with
7346 the arguments appropriate for substitution. For example,
7349 template <class T> struct S {};
7350 template <class T> struct S<T*> {};
7352 and supposing that we are instantiating S<int*>, ARGS will
7353 presently be {int*} -- but we need {int}. */
7354 pattern = TREE_TYPE (t);
7355 args = TREE_PURPOSE (t);
7359 pattern = TREE_TYPE (templ);
7360 args = CLASSTYPE_TI_ARGS (type);
7363 /* If the template we're instantiating is incomplete, then clearly
7364 there's nothing we can do. */
7365 if (!COMPLETE_TYPE_P (pattern))
7368 /* If we've recursively instantiated too many templates, stop. */
7369 if (! push_tinst_level (type))
7372 /* Now we're really doing the instantiation. Mark the type as in
7373 the process of being defined. */
7374 TYPE_BEING_DEFINED (type) = 1;
7376 /* We may be in the middle of deferred access check. Disable
7378 push_deferring_access_checks (dk_no_deferred);
7380 push_to_top_level ();
7382 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
7384 /* Set the input location to the most specialized template definition.
7385 This is needed if tsubsting causes an error. */
7386 typedecl = TYPE_MAIN_DECL (pattern);
7387 input_location = DECL_SOURCE_LOCATION (typedecl);
7389 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
7390 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
7391 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
7392 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
7393 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
7394 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
7395 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
7396 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
7397 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
7398 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
7399 TYPE_PACKED (type) = TYPE_PACKED (pattern);
7400 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
7401 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
7402 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
7403 if (ANON_AGGR_TYPE_P (pattern))
7404 SET_ANON_AGGR_TYPE_P (type);
7405 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
7407 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
7408 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
7411 pbinfo = TYPE_BINFO (pattern);
7413 /* We should never instantiate a nested class before its enclosing
7414 class; we need to look up the nested class by name before we can
7415 instantiate it, and that lookup should instantiate the enclosing
7417 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
7418 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
7419 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
7421 base_list = NULL_TREE;
7422 if (BINFO_N_BASE_BINFOS (pbinfo))
7425 tree context = TYPE_CONTEXT (type);
7429 /* We must enter the scope containing the type, as that is where
7430 the accessibility of types named in dependent bases are
7432 pushed_scope = push_scope (context ? context : global_namespace);
7434 /* Substitute into each of the bases to determine the actual
7436 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
7439 tree access = BINFO_BASE_ACCESS (pbinfo, i);
7440 tree expanded_bases = NULL_TREE;
7443 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
7446 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
7447 args, tf_error, NULL_TREE);
7448 if (expanded_bases == error_mark_node)
7451 len = TREE_VEC_LENGTH (expanded_bases);
7454 for (idx = 0; idx < len; idx++)
7457 /* Extract the already-expanded base class. */
7458 base = TREE_VEC_ELT (expanded_bases, idx);
7460 /* Substitute to figure out the base class. */
7461 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
7464 if (base == error_mark_node)
7467 base_list = tree_cons (access, base, base_list);
7468 if (BINFO_VIRTUAL_P (pbase_binfo))
7469 TREE_TYPE (base_list) = integer_type_node;
7473 /* The list is now in reverse order; correct that. */
7474 base_list = nreverse (base_list);
7477 pop_scope (pushed_scope);
7479 /* Now call xref_basetypes to set up all the base-class
7481 xref_basetypes (type, base_list);
7483 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
7484 (int) ATTR_FLAG_TYPE_IN_PLACE,
7485 args, tf_error, NULL_TREE);
7487 /* Now that our base classes are set up, enter the scope of the
7488 class, so that name lookups into base classes, etc. will work
7489 correctly. This is precisely analogous to what we do in
7490 begin_class_definition when defining an ordinary non-template
7491 class, except we also need to push the enclosing classes. */
7492 push_nested_class (type);
7494 /* Now members are processed in the order of declaration. */
7495 for (member = CLASSTYPE_DECL_LIST (pattern);
7496 member; member = TREE_CHAIN (member))
7498 tree t = TREE_VALUE (member);
7500 if (TREE_PURPOSE (member))
7504 /* Build new CLASSTYPE_NESTED_UTDS. */
7507 bool class_template_p;
7509 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
7510 && TYPE_LANG_SPECIFIC (t)
7511 && CLASSTYPE_IS_TEMPLATE (t));
7512 /* If the member is a class template, then -- even after
7513 substitution -- there may be dependent types in the
7514 template argument list for the class. We increment
7515 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
7516 that function will assume that no types are dependent
7517 when outside of a template. */
7518 if (class_template_p)
7519 ++processing_template_decl;
7520 newtag = tsubst (t, args, tf_error, NULL_TREE);
7521 if (class_template_p)
7522 --processing_template_decl;
7523 if (newtag == error_mark_node)
7526 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
7528 tree name = TYPE_IDENTIFIER (t);
7530 if (class_template_p)
7531 /* Unfortunately, lookup_template_class sets
7532 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
7533 instantiation (i.e., for the type of a member
7534 template class nested within a template class.)
7535 This behavior is required for
7536 maybe_process_partial_specialization to work
7537 correctly, but is not accurate in this case;
7538 the TAG is not an instantiation of anything.
7539 (The corresponding TEMPLATE_DECL is an
7540 instantiation, but the TYPE is not.) */
7541 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
7543 /* Now, we call pushtag to put this NEWTAG into the scope of
7544 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
7545 pushtag calling push_template_decl. We don't have to do
7546 this for enums because it will already have been done in
7549 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
7550 pushtag (name, newtag, /*tag_scope=*/ts_current);
7553 else if (TREE_CODE (t) == FUNCTION_DECL
7554 || DECL_FUNCTION_TEMPLATE_P (t))
7556 /* Build new TYPE_METHODS. */
7559 if (TREE_CODE (t) == TEMPLATE_DECL)
7560 ++processing_template_decl;
7561 r = tsubst (t, args, tf_error, NULL_TREE);
7562 if (TREE_CODE (t) == TEMPLATE_DECL)
7563 --processing_template_decl;
7564 set_current_access_from_decl (r);
7565 finish_member_declaration (r);
7569 /* Build new TYPE_FIELDS. */
7570 if (TREE_CODE (t) == STATIC_ASSERT)
7573 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
7574 tf_warning_or_error, NULL_TREE,
7575 /*integral_constant_expression_p=*/true);
7576 finish_static_assert (condition,
7577 STATIC_ASSERT_MESSAGE (t),
7578 STATIC_ASSERT_SOURCE_LOCATION (t),
7581 else if (TREE_CODE (t) != CONST_DECL)
7585 /* The file and line for this declaration, to
7586 assist in error message reporting. Since we
7587 called push_tinst_level above, we don't need to
7589 input_location = DECL_SOURCE_LOCATION (t);
7591 if (TREE_CODE (t) == TEMPLATE_DECL)
7592 ++processing_template_decl;
7593 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
7594 if (TREE_CODE (t) == TEMPLATE_DECL)
7595 --processing_template_decl;
7596 if (TREE_CODE (r) == VAR_DECL)
7600 [t]he initialization (and any associated
7601 side-effects) of a static data member does
7602 not occur unless the static data member is
7603 itself used in a way that requires the
7604 definition of the static data member to
7607 Therefore, we do not substitute into the
7608 initialized for the static data member here. */
7609 finish_static_data_member_decl
7612 /*init_const_expr_p=*/false,
7613 /*asmspec_tree=*/NULL_TREE,
7615 if (DECL_INITIALIZED_IN_CLASS_P (r))
7616 check_static_variable_definition (r, TREE_TYPE (r));
7618 else if (TREE_CODE (r) == FIELD_DECL)
7620 /* Determine whether R has a valid type and can be
7621 completed later. If R is invalid, then it is
7622 replaced by error_mark_node so that it will not be
7623 added to TYPE_FIELDS. */
7624 tree rtype = TREE_TYPE (r);
7625 if (can_complete_type_without_circularity (rtype))
7626 complete_type (rtype);
7628 if (!COMPLETE_TYPE_P (rtype))
7630 cxx_incomplete_type_error (r, rtype);
7631 r = error_mark_node;
7635 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
7636 such a thing will already have been added to the field
7637 list by tsubst_enum in finish_member_declaration in the
7638 CLASSTYPE_NESTED_UTDS case above. */
7639 if (!(TREE_CODE (r) == TYPE_DECL
7640 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
7641 && DECL_ARTIFICIAL (r)))
7643 set_current_access_from_decl (r);
7644 finish_member_declaration (r);
7651 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
7653 /* Build new CLASSTYPE_FRIEND_CLASSES. */
7655 tree friend_type = t;
7656 bool adjust_processing_template_decl = false;
7658 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7660 /* template <class T> friend class C; */
7661 friend_type = tsubst_friend_class (friend_type, args);
7662 adjust_processing_template_decl = true;
7664 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
7666 /* template <class T> friend class C::D; */
7667 friend_type = tsubst (friend_type, args,
7668 tf_warning_or_error, NULL_TREE);
7669 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7670 friend_type = TREE_TYPE (friend_type);
7671 adjust_processing_template_decl = true;
7673 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
7675 /* This could be either
7679 when dependent_type_p is false or
7681 template <class U> friend class T::C;
7684 friend_type = tsubst (friend_type, args,
7685 tf_warning_or_error, NULL_TREE);
7686 /* Bump processing_template_decl for correct
7687 dependent_type_p calculation. */
7688 ++processing_template_decl;
7689 if (dependent_type_p (friend_type))
7690 adjust_processing_template_decl = true;
7691 --processing_template_decl;
7693 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
7694 && hidden_name_p (TYPE_NAME (friend_type)))
7698 where C hasn't been declared yet. Let's lookup name
7699 from namespace scope directly, bypassing any name that
7700 come from dependent base class. */
7701 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
7703 /* The call to xref_tag_from_type does injection for friend
7705 push_nested_namespace (ns);
7707 xref_tag_from_type (friend_type, NULL_TREE,
7708 /*tag_scope=*/ts_current);
7709 pop_nested_namespace (ns);
7711 else if (uses_template_parms (friend_type))
7712 /* friend class C<T>; */
7713 friend_type = tsubst (friend_type, args,
7714 tf_warning_or_error, NULL_TREE);
7719 where C is already declared or
7721 friend class C<int>;
7723 We don't have to do anything in these cases. */
7725 if (adjust_processing_template_decl)
7726 /* Trick make_friend_class into realizing that the friend
7727 we're adding is a template, not an ordinary class. It's
7728 important that we use make_friend_class since it will
7729 perform some error-checking and output cross-reference
7731 ++processing_template_decl;
7733 if (friend_type != error_mark_node)
7734 make_friend_class (type, friend_type, /*complain=*/false);
7736 if (adjust_processing_template_decl)
7737 --processing_template_decl;
7741 /* Build new DECL_FRIENDLIST. */
7744 /* The file and line for this declaration, to
7745 assist in error message reporting. Since we
7746 called push_tinst_level above, we don't need to
7748 input_location = DECL_SOURCE_LOCATION (t);
7750 if (TREE_CODE (t) == TEMPLATE_DECL)
7752 ++processing_template_decl;
7753 push_deferring_access_checks (dk_no_check);
7756 r = tsubst_friend_function (t, args);
7757 add_friend (type, r, /*complain=*/false);
7758 if (TREE_CODE (t) == TEMPLATE_DECL)
7760 pop_deferring_access_checks ();
7761 --processing_template_decl;
7767 /* Set the file and line number information to whatever is given for
7768 the class itself. This puts error messages involving generated
7769 implicit functions at a predictable point, and the same point
7770 that would be used for non-template classes. */
7771 input_location = DECL_SOURCE_LOCATION (typedecl);
7773 unreverse_member_declarations (type);
7774 finish_struct_1 (type);
7775 TYPE_BEING_DEFINED (type) = 0;
7777 /* Now that the class is complete, instantiate default arguments for
7778 any member functions. We don't do this earlier because the
7779 default arguments may reference members of the class. */
7780 if (!PRIMARY_TEMPLATE_P (templ))
7781 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
7782 if (TREE_CODE (t) == FUNCTION_DECL
7783 /* Implicitly generated member functions will not have template
7784 information; they are not instantiations, but instead are
7785 created "fresh" for each instantiation. */
7786 && DECL_TEMPLATE_INFO (t))
7787 tsubst_default_arguments (t);
7789 /* Some typedefs referenced from within the template code need to be access
7790 checked at template instantiation time, i.e now. These types were
7791 added to the template at parsing time. Let's get those and perform
7792 the access checks then. */
7793 perform_typedefs_access_check (pattern, args);
7794 perform_deferred_access_checks ();
7795 pop_nested_class ();
7796 pop_from_top_level ();
7797 pop_deferring_access_checks ();
7800 /* The vtable for a template class can be emitted in any translation
7801 unit in which the class is instantiated. When there is no key
7802 method, however, finish_struct_1 will already have added TYPE to
7803 the keyed_classes list. */
7804 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
7805 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
7811 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7817 else if (TYPE_P (t))
7818 r = tsubst (t, args, complain, in_decl);
7821 r = tsubst_expr (t, args, complain, in_decl,
7822 /*integral_constant_expression_p=*/true);
7823 r = fold_non_dependent_expr (r);
7828 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
7829 NONTYPE_ARGUMENT_PACK. */
7832 make_fnparm_pack (tree spec_parm)
7834 /* Collect all of the extra "packed" parameters into an
7838 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
7839 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
7840 int i, len = list_length (spec_parm);
7842 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
7843 parmvec = make_tree_vec (len);
7844 parmtypevec = make_tree_vec (len);
7845 for (i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
7847 TREE_VEC_ELT (parmvec, i) = spec_parm;
7848 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
7851 /* Build the argument packs. */
7852 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
7853 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
7854 TREE_TYPE (argpack) = argtypepack;
7859 /* Substitute ARGS into T, which is an pack expansion
7860 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
7861 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
7862 (if only a partial substitution could be performed) or
7863 ERROR_MARK_NODE if there was an error. */
7865 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
7869 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
7870 tree first_arg_pack; int i, len = -1;
7873 bool very_local_specializations = false;
7875 gcc_assert (PACK_EXPANSION_P (t));
7876 pattern = PACK_EXPANSION_PATTERN (t);
7878 /* Determine the argument packs that will instantiate the parameter
7879 packs used in the expansion expression. While we're at it,
7880 compute the number of arguments to be expanded and make sure it
7882 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
7883 pack = TREE_CHAIN (pack))
7885 tree parm_pack = TREE_VALUE (pack);
7886 tree arg_pack = NULL_TREE;
7887 tree orig_arg = NULL_TREE;
7889 if (TREE_CODE (parm_pack) == PARM_DECL)
7891 arg_pack = retrieve_local_specialization (parm_pack);
7892 if (arg_pack == NULL_TREE)
7894 /* This can happen for a parameter name used later in a function
7895 declaration (such as in a late-specified return type). Just
7896 make a dummy decl, since it's only used for its type. */
7897 gcc_assert (cp_unevaluated_operand != 0);
7898 arg_pack = tsubst_decl (parm_pack, args, complain);
7899 arg_pack = make_fnparm_pack (arg_pack);
7904 int level, idx, levels;
7905 template_parm_level_and_index (parm_pack, &level, &idx);
7907 levels = TMPL_ARGS_DEPTH (args);
7908 if (level <= levels)
7909 arg_pack = TMPL_ARG (args, level, idx);
7912 orig_arg = arg_pack;
7913 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
7914 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
7916 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
7917 /* This can only happen if we forget to expand an argument
7918 pack somewhere else. Just return an error, silently. */
7920 result = make_tree_vec (1);
7921 TREE_VEC_ELT (result, 0) = error_mark_node;
7926 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
7927 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
7929 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
7930 tree pattern = PACK_EXPANSION_PATTERN (expansion);
7931 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
7932 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
7933 /* The argument pack that the parameter maps to is just an
7934 expansion of the parameter itself, such as one would
7935 find in the implicit typedef of a class inside the
7936 class itself. Consider this parameter "unsubstituted",
7937 so that we will maintain the outer pack expansion. */
7938 arg_pack = NULL_TREE;
7944 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
7946 /* It's all-or-nothing with incomplete argument packs. */
7947 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7948 return error_mark_node;
7950 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7956 first_arg_pack = arg_pack;
7958 else if (len != my_len)
7961 /* We got explicit args for some packs but not others;
7962 do nothing now and try again after deduction. */
7964 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
7965 error ("mismatched argument pack lengths while expanding "
7969 error ("mismatched argument pack lengths while expanding "
7972 return error_mark_node;
7975 /* Keep track of the parameter packs and their corresponding
7977 packs = tree_cons (parm_pack, arg_pack, packs);
7978 TREE_TYPE (packs) = orig_arg;
7981 /* We can't substitute for this parameter pack. */
7982 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
7984 unsubstituted_packs);
7987 /* We cannot expand this expansion expression, because we don't have
7988 all of the argument packs we need. Substitute into the pattern
7989 and return a PACK_EXPANSION_*. The caller will need to deal with
7991 if (unsubstituted_packs)
7994 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
7995 new_pat = tsubst_expr (pattern, args, complain, in_decl,
7996 /*integral_constant_expression_p=*/false);
7998 new_pat = tsubst (pattern, args, complain, in_decl);
7999 return make_pack_expansion (new_pat);
8002 /* We could not find any argument packs that work. */
8004 return error_mark_node;
8006 if (!local_specializations)
8008 /* We're in a late-specified return type, so we don't have a local
8009 specializations table. Create one for doing this expansion. */
8010 very_local_specializations = true;
8011 local_specializations = htab_create (37,
8012 hash_local_specialization,
8013 eq_local_specializations,
8017 /* For each argument in each argument pack, substitute into the
8019 result = make_tree_vec (len + incomplete);
8020 for (i = 0; i < len + incomplete; ++i)
8022 /* For parameter pack, change the substitution of the parameter
8023 pack to the ith argument in its argument pack, then expand
8025 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8027 tree parm = TREE_PURPOSE (pack);
8029 if (TREE_CODE (parm) == PARM_DECL)
8031 /* Select the Ith argument from the pack. */
8032 tree arg = make_node (ARGUMENT_PACK_SELECT);
8033 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
8034 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
8036 register_local_specialization (arg, parm);
8042 template_parm_level_and_index (parm, &level, &idx);
8046 /* Select the Ith argument from the pack. */
8047 value = make_node (ARGUMENT_PACK_SELECT);
8048 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
8049 ARGUMENT_PACK_SELECT_INDEX (value) = i;
8052 /* Update the corresponding argument. */
8053 TMPL_ARG (args, level, idx) = value;
8057 /* Substitute into the PATTERN with the altered arguments. */
8058 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8059 TREE_VEC_ELT (result, i) =
8060 tsubst_expr (pattern, args, complain, in_decl,
8061 /*integral_constant_expression_p=*/false);
8063 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
8066 /* When we have incomplete argument packs, the last "expanded"
8067 result is itself a pack expansion, which allows us
8068 to deduce more arguments. */
8069 TREE_VEC_ELT (result, i) =
8070 make_pack_expansion (TREE_VEC_ELT (result, i));
8072 if (TREE_VEC_ELT (result, i) == error_mark_node)
8074 result = error_mark_node;
8079 /* Update ARGS to restore the substitution from parameter packs to
8080 their argument packs. */
8081 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8083 tree parm = TREE_PURPOSE (pack);
8085 if (TREE_CODE (parm) == PARM_DECL)
8086 register_local_specialization (TREE_TYPE (pack), parm);
8090 template_parm_level_and_index (parm, &level, &idx);
8092 /* Update the corresponding argument. */
8093 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
8094 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
8097 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
8101 if (very_local_specializations)
8103 htab_delete (local_specializations);
8104 local_specializations = NULL;
8110 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
8111 TMPL. We do this using DECL_PARM_INDEX, which should work even with
8112 parameter packs; all parms generated from a function parameter pack will
8113 have the same DECL_PARM_INDEX. */
8116 get_pattern_parm (tree parm, tree tmpl)
8118 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
8121 if (DECL_ARTIFICIAL (parm))
8123 for (patparm = DECL_ARGUMENTS (pattern);
8124 patparm; patparm = TREE_CHAIN (patparm))
8125 if (DECL_ARTIFICIAL (patparm)
8126 && DECL_NAME (parm) == DECL_NAME (patparm))
8131 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
8132 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
8133 gcc_assert (DECL_PARM_INDEX (patparm)
8134 == DECL_PARM_INDEX (parm));
8140 /* Substitute ARGS into the vector or list of template arguments T. */
8143 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8146 int len = TREE_VEC_LENGTH (t);
8147 int need_new = 0, i, expanded_len_adjust = 0, out;
8148 tree *elts = (tree *) alloca (len * sizeof (tree));
8150 for (i = 0; i < len; i++)
8152 tree orig_arg = TREE_VEC_ELT (t, i);
8155 if (TREE_CODE (orig_arg) == TREE_VEC)
8156 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
8157 else if (PACK_EXPANSION_P (orig_arg))
8159 /* Substitute into an expansion expression. */
8160 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
8162 if (TREE_CODE (new_arg) == TREE_VEC)
8163 /* Add to the expanded length adjustment the number of
8164 expanded arguments. We subtract one from this
8165 measurement, because the argument pack expression
8166 itself is already counted as 1 in
8167 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
8168 the argument pack is empty. */
8169 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
8171 else if (ARGUMENT_PACK_P (orig_arg))
8173 /* Substitute into each of the arguments. */
8174 new_arg = TYPE_P (orig_arg)
8175 ? cxx_make_type (TREE_CODE (orig_arg))
8176 : make_node (TREE_CODE (orig_arg));
8178 SET_ARGUMENT_PACK_ARGS (
8180 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
8181 args, complain, in_decl));
8183 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
8184 new_arg = error_mark_node;
8186 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
8187 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
8189 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
8191 if (TREE_TYPE (new_arg) == error_mark_node)
8192 new_arg = error_mark_node;
8196 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
8198 if (new_arg == error_mark_node)
8199 return error_mark_node;
8202 if (new_arg != orig_arg)
8209 /* Make space for the expanded arguments coming from template
8211 t = make_tree_vec (len + expanded_len_adjust);
8212 for (i = 0, out = 0; i < len; i++)
8214 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
8215 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
8216 && TREE_CODE (elts[i]) == TREE_VEC)
8220 /* Now expand the template argument pack "in place". */
8221 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
8222 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
8226 TREE_VEC_ELT (t, out) = elts[i];
8234 /* Return the result of substituting ARGS into the template parameters
8235 given by PARMS. If there are m levels of ARGS and m + n levels of
8236 PARMS, then the result will contain n levels of PARMS. For
8237 example, if PARMS is `template <class T> template <class U>
8238 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
8239 result will be `template <int*, double, class V>'. */
8242 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
8247 /* When substituting into a template, we must set
8248 PROCESSING_TEMPLATE_DECL as the template parameters may be
8249 dependent if they are based on one-another, and the dependency
8250 predicates are short-circuit outside of templates. */
8251 ++processing_template_decl;
8253 for (new_parms = &r;
8254 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
8255 new_parms = &(TREE_CHAIN (*new_parms)),
8256 parms = TREE_CHAIN (parms))
8259 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
8262 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
8268 if (parms == error_mark_node)
8271 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
8273 if (tuple == error_mark_node)
8276 default_value = TREE_PURPOSE (tuple);
8277 parm_decl = TREE_VALUE (tuple);
8279 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
8280 if (TREE_CODE (parm_decl) == PARM_DECL
8281 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
8282 parm_decl = error_mark_node;
8283 default_value = tsubst_template_arg (default_value, args,
8284 complain, NULL_TREE);
8286 tuple = build_tree_list (default_value, parm_decl);
8287 TREE_VEC_ELT (new_vec, i) = tuple;
8291 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
8292 - TMPL_ARGS_DEPTH (args)),
8293 new_vec, NULL_TREE);
8296 --processing_template_decl;
8301 /* Substitute the ARGS into the indicated aggregate (or enumeration)
8302 type T. If T is not an aggregate or enumeration type, it is
8303 handled as if by tsubst. IN_DECL is as for tsubst. If
8304 ENTERING_SCOPE is nonzero, T is the context for a template which
8305 we are presently tsubst'ing. Return the substituted value. */
8308 tsubst_aggr_type (tree t,
8310 tsubst_flags_t complain,
8317 switch (TREE_CODE (t))
8320 if (TYPE_PTRMEMFUNC_P (t))
8321 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
8323 /* Else fall through. */
8326 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
8331 int saved_unevaluated_operand;
8332 int saved_inhibit_evaluation_warnings;
8334 /* In "sizeof(X<I>)" we need to evaluate "I". */
8335 saved_unevaluated_operand = cp_unevaluated_operand;
8336 cp_unevaluated_operand = 0;
8337 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
8338 c_inhibit_evaluation_warnings = 0;
8340 /* First, determine the context for the type we are looking
8342 context = TYPE_CONTEXT (t);
8345 context = tsubst_aggr_type (context, args, complain,
8346 in_decl, /*entering_scope=*/1);
8347 /* If context is a nested class inside a class template,
8348 it may still need to be instantiated (c++/33959). */
8349 if (TYPE_P (context))
8350 context = complete_type (context);
8353 /* Then, figure out what arguments are appropriate for the
8354 type we are trying to find. For example, given:
8356 template <class T> struct S;
8357 template <class T, class U> void f(T, U) { S<U> su; }
8359 and supposing that we are instantiating f<int, double>,
8360 then our ARGS will be {int, double}, but, when looking up
8361 S we only want {double}. */
8362 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
8364 if (argvec == error_mark_node)
8365 r = error_mark_node;
8368 r = lookup_template_class (t, argvec, in_decl, context,
8369 entering_scope, complain);
8370 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
8373 cp_unevaluated_operand = saved_unevaluated_operand;
8374 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
8379 /* This is not a template type, so there's nothing to do. */
8383 return tsubst (t, args, complain, in_decl);
8387 /* Substitute into the default argument ARG (a default argument for
8388 FN), which has the indicated TYPE. */
8391 tsubst_default_argument (tree fn, tree type, tree arg)
8393 tree saved_class_ptr = NULL_TREE;
8394 tree saved_class_ref = NULL_TREE;
8396 /* This default argument came from a template. Instantiate the
8397 default argument here, not in tsubst. In the case of
8406 we must be careful to do name lookup in the scope of S<T>,
8407 rather than in the current class. */
8408 push_access_scope (fn);
8409 /* The "this" pointer is not valid in a default argument. */
8412 saved_class_ptr = current_class_ptr;
8413 cp_function_chain->x_current_class_ptr = NULL_TREE;
8414 saved_class_ref = current_class_ref;
8415 cp_function_chain->x_current_class_ref = NULL_TREE;
8418 push_deferring_access_checks(dk_no_deferred);
8419 /* The default argument expression may cause implicitly defined
8420 member functions to be synthesized, which will result in garbage
8421 collection. We must treat this situation as if we were within
8422 the body of function so as to avoid collecting live data on the
8425 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
8426 tf_warning_or_error, NULL_TREE,
8427 /*integral_constant_expression_p=*/false);
8429 pop_deferring_access_checks();
8431 /* Restore the "this" pointer. */
8434 cp_function_chain->x_current_class_ptr = saved_class_ptr;
8435 cp_function_chain->x_current_class_ref = saved_class_ref;
8438 /* Make sure the default argument is reasonable. */
8439 arg = check_default_argument (type, arg);
8441 pop_access_scope (fn);
8446 /* Substitute into all the default arguments for FN. */
8449 tsubst_default_arguments (tree fn)
8454 tmpl_args = DECL_TI_ARGS (fn);
8456 /* If this function is not yet instantiated, we certainly don't need
8457 its default arguments. */
8458 if (uses_template_parms (tmpl_args))
8461 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
8463 arg = TREE_CHAIN (arg))
8464 if (TREE_PURPOSE (arg))
8465 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
8467 TREE_PURPOSE (arg));
8470 /* Substitute the ARGS into the T, which is a _DECL. Return the
8471 result of the substitution. Issue error and warning messages under
8472 control of COMPLAIN. */
8475 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
8477 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
8478 location_t saved_loc;
8483 /* Set the filename and linenumber to improve error-reporting. */
8484 saved_loc = input_location;
8485 input_location = DECL_SOURCE_LOCATION (t);
8487 switch (TREE_CODE (t))
8491 /* We can get here when processing a member function template,
8492 member class template, or template template parameter. */
8493 tree decl = DECL_TEMPLATE_RESULT (t);
8498 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
8500 /* Template template parameter is treated here. */
8501 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8502 if (new_type == error_mark_node)
8503 RETURN (error_mark_node);
8506 TREE_CHAIN (r) = NULL_TREE;
8507 TREE_TYPE (r) = new_type;
8508 DECL_TEMPLATE_RESULT (r)
8509 = build_decl (DECL_SOURCE_LOCATION (decl),
8510 TYPE_DECL, DECL_NAME (decl), new_type);
8511 DECL_TEMPLATE_PARMS (r)
8512 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8514 TYPE_NAME (new_type) = r;
8518 /* We might already have an instance of this template.
8519 The ARGS are for the surrounding class type, so the
8520 full args contain the tsubst'd args for the context,
8521 plus the innermost args from the template decl. */
8522 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
8523 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
8524 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
8525 /* Because this is a template, the arguments will still be
8526 dependent, even after substitution. If
8527 PROCESSING_TEMPLATE_DECL is not set, the dependency
8528 predicates will short-circuit. */
8529 ++processing_template_decl;
8530 full_args = tsubst_template_args (tmpl_args, args,
8532 --processing_template_decl;
8533 if (full_args == error_mark_node)
8534 RETURN (error_mark_node);
8536 /* If this is a default template template argument,
8537 tsubst might not have changed anything. */
8538 if (full_args == tmpl_args)
8541 hash = hash_tmpl_and_args (t, full_args);
8542 spec = retrieve_specialization (t, full_args, hash);
8543 if (spec != NULL_TREE)
8549 /* Make a new template decl. It will be similar to the
8550 original, but will record the current template arguments.
8551 We also create a new function declaration, which is just
8552 like the old one, but points to this new template, rather
8553 than the old one. */
8555 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
8556 TREE_CHAIN (r) = NULL_TREE;
8558 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
8560 if (TREE_CODE (decl) == TYPE_DECL)
8563 ++processing_template_decl;
8564 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8565 --processing_template_decl;
8566 if (new_type == error_mark_node)
8567 RETURN (error_mark_node);
8569 TREE_TYPE (r) = new_type;
8570 CLASSTYPE_TI_TEMPLATE (new_type) = r;
8571 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
8572 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
8573 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
8578 ++processing_template_decl;
8579 new_decl = tsubst (decl, args, complain, in_decl);
8580 --processing_template_decl;
8581 if (new_decl == error_mark_node)
8582 RETURN (error_mark_node);
8584 DECL_TEMPLATE_RESULT (r) = new_decl;
8585 DECL_TI_TEMPLATE (new_decl) = r;
8586 TREE_TYPE (r) = TREE_TYPE (new_decl);
8587 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
8588 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
8591 SET_DECL_IMPLICIT_INSTANTIATION (r);
8592 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
8593 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
8595 /* The template parameters for this new template are all the
8596 template parameters for the old template, except the
8597 outermost level of parameters. */
8598 DECL_TEMPLATE_PARMS (r)
8599 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8602 if (PRIMARY_TEMPLATE_P (t))
8603 DECL_PRIMARY_TEMPLATE (r) = r;
8605 if (TREE_CODE (decl) != TYPE_DECL)
8606 /* Record this non-type partial instantiation. */
8607 register_specialization (r, t,
8608 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
8616 tree argvec = NULL_TREE;
8624 /* Nobody should be tsubst'ing into non-template functions. */
8625 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
8627 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
8632 /* If T is not dependent, just return it. We have to
8633 increment PROCESSING_TEMPLATE_DECL because
8634 value_dependent_expression_p assumes that nothing is
8635 dependent when PROCESSING_TEMPLATE_DECL is zero. */
8636 ++processing_template_decl;
8637 dependent_p = value_dependent_expression_p (t);
8638 --processing_template_decl;
8642 /* Calculate the most general template of which R is a
8643 specialization, and the complete set of arguments used to
8645 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
8646 argvec = tsubst_template_args (DECL_TI_ARGS
8647 (DECL_TEMPLATE_RESULT (gen_tmpl)),
8648 args, complain, in_decl);
8650 /* Check to see if we already have this specialization. */
8651 hash = hash_tmpl_and_args (gen_tmpl, argvec);
8652 spec = retrieve_specialization (gen_tmpl, argvec, hash);
8660 /* We can see more levels of arguments than parameters if
8661 there was a specialization of a member template, like
8664 template <class T> struct S { template <class U> void f(); }
8665 template <> template <class U> void S<int>::f(U);
8667 Here, we'll be substituting into the specialization,
8668 because that's where we can find the code we actually
8669 want to generate, but we'll have enough arguments for
8670 the most general template.
8672 We also deal with the peculiar case:
8674 template <class T> struct S {
8675 template <class U> friend void f();
8677 template <class U> void f() {}
8679 template void f<double>();
8681 Here, the ARGS for the instantiation of will be {int,
8682 double}. But, we only need as many ARGS as there are
8683 levels of template parameters in CODE_PATTERN. We are
8684 careful not to get fooled into reducing the ARGS in
8687 template <class T> struct S { template <class U> void f(U); }
8688 template <class T> template <> void S<T>::f(int) {}
8690 which we can spot because the pattern will be a
8691 specialization in this case. */
8692 args_depth = TMPL_ARGS_DEPTH (args);
8694 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
8695 if (args_depth > parms_depth
8696 && !DECL_TEMPLATE_SPECIALIZATION (t))
8697 args = get_innermost_template_args (args, parms_depth);
8701 /* This special case arises when we have something like this:
8703 template <class T> struct S {
8704 friend void f<int>(int, double);
8707 Here, the DECL_TI_TEMPLATE for the friend declaration
8708 will be an IDENTIFIER_NODE. We are being called from
8709 tsubst_friend_function, and we want only to create a
8710 new decl (R) with appropriate types so that we can call
8711 determine_specialization. */
8712 gen_tmpl = NULL_TREE;
8715 if (DECL_CLASS_SCOPE_P (t))
8717 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
8721 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
8722 complain, t, /*entering_scope=*/1);
8727 ctx = DECL_CONTEXT (t);
8729 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8730 if (type == error_mark_node)
8731 RETURN (error_mark_node);
8733 /* We do NOT check for matching decls pushed separately at this
8734 point, as they may not represent instantiations of this
8735 template, and in any case are considered separate under the
8738 DECL_USE_TEMPLATE (r) = 0;
8739 TREE_TYPE (r) = type;
8740 /* Clear out the mangled name and RTL for the instantiation. */
8741 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8742 SET_DECL_RTL (r, NULL_RTX);
8743 /* Leave DECL_INITIAL set on deleted instantiations. */
8744 if (!DECL_DELETED_FN (r))
8745 DECL_INITIAL (r) = NULL_TREE;
8746 DECL_CONTEXT (r) = ctx;
8748 if (member && DECL_CONV_FN_P (r))
8749 /* Type-conversion operator. Reconstruct the name, in
8750 case it's the name of one of the template's parameters. */
8751 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
8753 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
8755 DECL_RESULT (r) = NULL_TREE;
8757 TREE_STATIC (r) = 0;
8758 TREE_PUBLIC (r) = TREE_PUBLIC (t);
8759 DECL_EXTERNAL (r) = 1;
8760 /* If this is an instantiation of a function with internal
8761 linkage, we already know what object file linkage will be
8762 assigned to the instantiation. */
8763 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
8764 DECL_DEFER_OUTPUT (r) = 0;
8765 TREE_CHAIN (r) = NULL_TREE;
8766 DECL_PENDING_INLINE_INFO (r) = 0;
8767 DECL_PENDING_INLINE_P (r) = 0;
8768 DECL_SAVED_TREE (r) = NULL_TREE;
8769 DECL_STRUCT_FUNCTION (r) = NULL;
8771 /* We'll re-clone as appropriate in instantiate_template. */
8772 DECL_CLONED_FUNCTION (r) = NULL_TREE;
8774 /* If we aren't complaining now, return on error before we register
8775 the specialization so that we'll complain eventually. */
8776 if ((complain & tf_error) == 0
8777 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
8778 && !grok_op_properties (r, /*complain=*/false))
8779 RETURN (error_mark_node);
8781 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
8782 this in the special friend case mentioned above where
8783 GEN_TMPL is NULL. */
8786 DECL_TEMPLATE_INFO (r)
8787 = tree_cons (gen_tmpl, argvec, NULL_TREE);
8788 SET_DECL_IMPLICIT_INSTANTIATION (r);
8789 register_specialization (r, gen_tmpl, argvec, false, hash);
8791 /* We're not supposed to instantiate default arguments
8792 until they are called, for a template. But, for a
8795 template <class T> void f ()
8796 { extern void g(int i = T()); }
8798 we should do the substitution when the template is
8799 instantiated. We handle the member function case in
8800 instantiate_class_template since the default arguments
8801 might refer to other members of the class. */
8803 && !PRIMARY_TEMPLATE_P (gen_tmpl)
8804 && !uses_template_parms (argvec))
8805 tsubst_default_arguments (r);
8808 DECL_TEMPLATE_INFO (r) = NULL_TREE;
8810 /* Copy the list of befriending classes. */
8811 for (friends = &DECL_BEFRIENDING_CLASSES (r);
8813 friends = &TREE_CHAIN (*friends))
8815 *friends = copy_node (*friends);
8816 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
8821 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
8823 maybe_retrofit_in_chrg (r);
8824 if (DECL_CONSTRUCTOR_P (r))
8825 grok_ctor_properties (ctx, r);
8826 /* If this is an instantiation of a member template, clone it.
8827 If it isn't, that'll be handled by
8828 clone_constructors_and_destructors. */
8829 if (PRIMARY_TEMPLATE_P (gen_tmpl))
8830 clone_function_decl (r, /*update_method_vec_p=*/0);
8832 else if ((complain & tf_error) != 0
8833 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
8834 && !grok_op_properties (r, /*complain=*/true))
8835 RETURN (error_mark_node);
8837 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
8838 SET_DECL_FRIEND_CONTEXT (r,
8839 tsubst (DECL_FRIEND_CONTEXT (t),
8840 args, complain, in_decl));
8842 /* Possibly limit visibility based on template args. */
8843 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8844 if (DECL_VISIBILITY_SPECIFIED (t))
8846 DECL_VISIBILITY_SPECIFIED (r) = 0;
8848 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8850 determine_visibility (r);
8852 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8853 args, complain, in_decl);
8859 tree type = NULL_TREE;
8861 tree expanded_types = NULL_TREE;
8862 tree prev_r = NULL_TREE;
8863 tree first_r = NULL_TREE;
8865 if (FUNCTION_PARAMETER_PACK_P (t))
8867 /* If there is a local specialization that isn't a
8868 parameter pack, it means that we're doing a "simple"
8869 substitution from inside tsubst_pack_expansion. Just
8870 return the local specialization (which will be a single
8872 tree spec = retrieve_local_specialization (t);
8874 && TREE_CODE (spec) == PARM_DECL
8875 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
8878 /* Expand the TYPE_PACK_EXPANSION that provides the types for
8879 the parameters in this function parameter pack. */
8880 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
8882 if (TREE_CODE (expanded_types) == TREE_VEC)
8884 len = TREE_VEC_LENGTH (expanded_types);
8886 /* Zero-length parameter packs are boring. Just substitute
8889 RETURN (tsubst (TREE_CHAIN (t), args, complain,
8894 /* All we did was update the type. Make a note of that. */
8895 type = expanded_types;
8896 expanded_types = NULL_TREE;
8900 /* Loop through all of the parameter's we'll build. When T is
8901 a function parameter pack, LEN is the number of expanded
8902 types in EXPANDED_TYPES; otherwise, LEN is 1. */
8904 for (i = 0; i < len; ++i)
8908 if (DECL_TEMPLATE_PARM_P (t))
8909 SET_DECL_TEMPLATE_PARM_P (r);
8911 /* An argument of a function parameter pack is not a parameter
8913 FUNCTION_PARAMETER_PACK_P (r) = false;
8916 /* We're on the Ith parameter of the function parameter
8919 /* Get the Ith type. */
8920 type = TREE_VEC_ELT (expanded_types, i);
8923 /* Rename the parameter to include the index. */
8925 make_ith_pack_parameter_name (DECL_NAME (r), i);
8928 /* We're dealing with a normal parameter. */
8929 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8931 type = type_decays_to (type);
8932 TREE_TYPE (r) = type;
8933 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8935 if (DECL_INITIAL (r))
8937 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
8938 DECL_INITIAL (r) = TREE_TYPE (r);
8940 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
8944 DECL_CONTEXT (r) = NULL_TREE;
8946 if (!DECL_TEMPLATE_PARM_P (r))
8947 DECL_ARG_TYPE (r) = type_passed_as (type);
8949 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8950 args, complain, in_decl);
8952 /* Keep track of the first new parameter we
8953 generate. That's what will be returned to the
8958 /* Build a proper chain of parameters when substituting
8959 into a function parameter pack. */
8961 TREE_CHAIN (prev_r) = r;
8965 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
8966 complain, TREE_CHAIN (t));
8968 /* FIRST_R contains the start of the chain we've built. */
8978 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8979 if (type == error_mark_node)
8980 RETURN (error_mark_node);
8981 TREE_TYPE (r) = type;
8982 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8984 /* DECL_INITIAL gives the number of bits in a bit-field. */
8986 = tsubst_expr (DECL_INITIAL (t), args,
8988 /*integral_constant_expression_p=*/true);
8989 /* We don't have to set DECL_CONTEXT here; it is set by
8990 finish_member_declaration. */
8991 TREE_CHAIN (r) = NULL_TREE;
8992 if (VOID_TYPE_P (type))
8993 error ("instantiation of %q+D as type %qT", r, type);
8995 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8996 args, complain, in_decl);
9001 /* We reach here only for member using decls. */
9002 if (DECL_DEPENDENT_P (t))
9004 r = do_class_using_decl
9005 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
9006 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
9008 r = error_mark_node;
9011 TREE_PROTECTED (r) = TREE_PROTECTED (t);
9012 TREE_PRIVATE (r) = TREE_PRIVATE (t);
9018 TREE_CHAIN (r) = NULL_TREE;
9025 tree argvec = NULL_TREE;
9026 tree gen_tmpl = NULL_TREE;
9028 tree tmpl = NULL_TREE;
9030 tree type = NULL_TREE;
9033 if (TREE_CODE (t) == TYPE_DECL
9034 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
9036 /* If this is the canonical decl, we don't have to
9037 mess with instantiations, and often we can't (for
9038 typename, template type parms and such). Note that
9039 TYPE_NAME is not correct for the above test if
9040 we've copied the type for a typedef. */
9041 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9042 if (type == error_mark_node)
9043 RETURN (error_mark_node);
9044 r = TYPE_NAME (type);
9048 /* Check to see if we already have the specialization we
9051 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
9053 /* T is a static data member or namespace-scope entity.
9054 We have to substitute into namespace-scope variables
9055 (even though such entities are never templates) because
9058 template <class T> void f() { extern T t; }
9060 where the entity referenced is not known until
9061 instantiation time. */
9063 ctx = DECL_CONTEXT (t);
9064 if (DECL_CLASS_SCOPE_P (t))
9066 ctx = tsubst_aggr_type (ctx, args,
9068 in_decl, /*entering_scope=*/1);
9069 /* If CTX is unchanged, then T is in fact the
9070 specialization we want. That situation occurs when
9071 referencing a static data member within in its own
9072 class. We can use pointer equality, rather than
9073 same_type_p, because DECL_CONTEXT is always
9075 if (ctx == DECL_CONTEXT (t))
9081 tmpl = DECL_TI_TEMPLATE (t);
9082 gen_tmpl = most_general_template (tmpl);
9083 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
9084 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9085 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9090 /* A local variable. */
9092 /* Subsequent calls to pushdecl will fill this in. */
9094 spec = retrieve_local_specialization (t);
9096 /* If we already have the specialization we need, there is
9097 nothing more to do. */
9104 /* Create a new node for the specialization we need. */
9106 if (type == NULL_TREE)
9107 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9108 if (TREE_CODE (r) == VAR_DECL)
9110 /* Even if the original location is out of scope, the
9111 newly substituted one is not. */
9112 DECL_DEAD_FOR_LOCAL (r) = 0;
9113 DECL_INITIALIZED_P (r) = 0;
9114 DECL_TEMPLATE_INSTANTIATED (r) = 0;
9115 if (type == error_mark_node)
9116 RETURN (error_mark_node);
9117 if (TREE_CODE (type) == FUNCTION_TYPE)
9119 /* It may seem that this case cannot occur, since:
9124 declares a function, not a variable. However:
9127 template <typename T> void g() { T t; }
9128 template void g<f>();
9130 is an attempt to declare a variable with function
9132 error ("variable %qD has function type",
9133 /* R is not yet sufficiently initialized, so we
9134 just use its name. */
9136 RETURN (error_mark_node);
9138 type = complete_type (type);
9139 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
9140 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
9141 type = check_var_type (DECL_NAME (r), type);
9143 if (DECL_HAS_VALUE_EXPR_P (t))
9145 tree ve = DECL_VALUE_EXPR (t);
9146 ve = tsubst_expr (ve, args, complain, in_decl,
9147 /*constant_expression_p=*/false);
9148 SET_DECL_VALUE_EXPR (r, ve);
9151 else if (DECL_SELF_REFERENCE_P (t))
9152 SET_DECL_SELF_REFERENCE_P (r);
9153 TREE_TYPE (r) = type;
9154 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9155 DECL_CONTEXT (r) = ctx;
9156 /* Clear out the mangled name and RTL for the instantiation. */
9157 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9158 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9159 SET_DECL_RTL (r, NULL_RTX);
9160 /* The initializer must not be expanded until it is required;
9162 DECL_INITIAL (r) = NULL_TREE;
9163 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9164 SET_DECL_RTL (r, NULL_RTX);
9165 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
9166 if (TREE_CODE (r) == VAR_DECL)
9168 /* Possibly limit visibility based on template args. */
9169 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9170 if (DECL_VISIBILITY_SPECIFIED (t))
9172 DECL_VISIBILITY_SPECIFIED (r) = 0;
9174 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9176 determine_visibility (r);
9178 /* Preserve a typedef that names a type. */
9179 else if (TREE_CODE (r) == TYPE_DECL
9180 && DECL_ORIGINAL_TYPE (t)
9181 && type != error_mark_node)
9183 DECL_ORIGINAL_TYPE (r) = tsubst (DECL_ORIGINAL_TYPE (t),
9184 args, complain, in_decl);
9185 TREE_TYPE (r) = type = build_variant_type_copy (type);
9186 TYPE_NAME (type) = r;
9191 /* A static data member declaration is always marked
9192 external when it is declared in-class, even if an
9193 initializer is present. We mimic the non-template
9195 DECL_EXTERNAL (r) = 1;
9197 register_specialization (r, gen_tmpl, argvec, false, hash);
9198 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
9199 SET_DECL_IMPLICIT_INSTANTIATION (r);
9201 else if (cp_unevaluated_operand)
9203 /* We're substituting this var in a decltype outside of its
9204 scope, such as for a lambda return type. Don't add it to
9205 local_specializations, do perform auto deduction. */
9206 tree auto_node = type_uses_auto (type);
9208 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
9209 /*constant_expression_p=*/false);
9211 if (auto_node && init && describable_type (init))
9213 type = do_auto_deduction (type, init, auto_node);
9214 TREE_TYPE (r) = type;
9218 register_local_specialization (r, t);
9220 TREE_CHAIN (r) = NULL_TREE;
9222 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
9223 (int) ATTR_FLAG_TYPE_IN_PLACE,
9224 args, complain, in_decl);
9235 /* Restore the file and line information. */
9236 input_location = saved_loc;
9241 /* Substitute into the ARG_TYPES of a function type. */
9244 tsubst_arg_types (tree arg_types,
9246 tsubst_flags_t complain,
9249 tree remaining_arg_types;
9250 tree type = NULL_TREE;
9252 tree expanded_args = NULL_TREE;
9255 if (!arg_types || arg_types == void_list_node)
9258 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
9259 args, complain, in_decl);
9260 if (remaining_arg_types == error_mark_node)
9261 return error_mark_node;
9263 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
9265 /* For a pack expansion, perform substitution on the
9266 entire expression. Later on, we'll handle the arguments
9268 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
9269 args, complain, in_decl);
9271 if (TREE_CODE (expanded_args) == TREE_VEC)
9272 /* So that we'll spin through the parameters, one by one. */
9273 i = TREE_VEC_LENGTH (expanded_args);
9276 /* We only partially substituted into the parameter
9277 pack. Our type is TYPE_PACK_EXPANSION. */
9278 type = expanded_args;
9279 expanded_args = NULL_TREE;
9287 type = TREE_VEC_ELT (expanded_args, i);
9289 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
9291 if (type == error_mark_node)
9292 return error_mark_node;
9293 if (VOID_TYPE_P (type))
9295 if (complain & tf_error)
9297 error ("invalid parameter type %qT", type);
9299 error ("in declaration %q+D", in_decl);
9301 return error_mark_node;
9304 /* Do array-to-pointer, function-to-pointer conversion, and ignore
9305 top-level qualifiers as required. */
9306 type = TYPE_MAIN_VARIANT (type_decays_to (type));
9308 /* We do not substitute into default arguments here. The standard
9309 mandates that they be instantiated only when needed, which is
9310 done in build_over_call. */
9311 default_arg = TREE_PURPOSE (arg_types);
9313 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
9315 /* We've instantiated a template before its default arguments
9316 have been parsed. This can happen for a nested template
9317 class, and is not an error unless we require the default
9318 argument in a call of this function. */
9319 remaining_arg_types =
9320 tree_cons (default_arg, type, remaining_arg_types);
9321 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
9322 remaining_arg_types);
9325 remaining_arg_types =
9326 hash_tree_cons (default_arg, type, remaining_arg_types);
9329 return remaining_arg_types;
9332 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
9333 *not* handle the exception-specification for FNTYPE, because the
9334 initial substitution of explicitly provided template parameters
9335 during argument deduction forbids substitution into the
9336 exception-specification:
9340 All references in the function type of the function template to the
9341 corresponding template parameters are replaced by the specified tem-
9342 plate argument values. If a substitution in a template parameter or
9343 in the function type of the function template results in an invalid
9344 type, type deduction fails. [Note: The equivalent substitution in
9345 exception specifications is done only when the function is instanti-
9346 ated, at which point a program is ill-formed if the substitution
9347 results in an invalid type.] */
9350 tsubst_function_type (tree t,
9352 tsubst_flags_t complain,
9359 /* The TYPE_CONTEXT is not used for function/method types. */
9360 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
9362 /* Substitute the return type. */
9363 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9364 if (return_type == error_mark_node)
9365 return error_mark_node;
9366 /* The standard does not presently indicate that creation of a
9367 function type with an invalid return type is a deduction failure.
9368 However, that is clearly analogous to creating an array of "void"
9369 or a reference to a reference. This is core issue #486. */
9370 if (TREE_CODE (return_type) == ARRAY_TYPE
9371 || TREE_CODE (return_type) == FUNCTION_TYPE)
9373 if (complain & tf_error)
9375 if (TREE_CODE (return_type) == ARRAY_TYPE)
9376 error ("function returning an array");
9378 error ("function returning a function");
9380 return error_mark_node;
9383 /* Substitute the argument types. */
9384 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
9386 if (arg_types == error_mark_node)
9387 return error_mark_node;
9389 /* Construct a new type node and return it. */
9390 if (TREE_CODE (t) == FUNCTION_TYPE)
9391 fntype = build_function_type (return_type, arg_types);
9394 tree r = TREE_TYPE (TREE_VALUE (arg_types));
9395 if (! MAYBE_CLASS_TYPE_P (r))
9399 Type deduction may fail for any of the following
9402 -- Attempting to create "pointer to member of T" when T
9403 is not a class type. */
9404 if (complain & tf_error)
9405 error ("creating pointer to member function of non-class type %qT",
9407 return error_mark_node;
9410 fntype = build_method_type_directly (r, return_type,
9411 TREE_CHAIN (arg_types));
9413 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
9414 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
9419 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
9420 ARGS into that specification, and return the substituted
9421 specification. If there is no specification, return NULL_TREE. */
9424 tsubst_exception_specification (tree fntype,
9426 tsubst_flags_t complain,
9432 specs = TYPE_RAISES_EXCEPTIONS (fntype);
9433 new_specs = NULL_TREE;
9436 if (! TREE_VALUE (specs))
9443 tree expanded_specs = NULL_TREE;
9445 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
9447 /* Expand the pack expansion type. */
9448 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
9452 if (expanded_specs == error_mark_node)
9453 return error_mark_node;
9454 else if (TREE_CODE (expanded_specs) == TREE_VEC)
9455 len = TREE_VEC_LENGTH (expanded_specs);
9458 /* We're substituting into a member template, so
9459 we got a TYPE_PACK_EXPANSION back. Add that
9460 expansion and move on. */
9461 gcc_assert (TREE_CODE (expanded_specs)
9462 == TYPE_PACK_EXPANSION);
9463 new_specs = add_exception_specifier (new_specs,
9466 specs = TREE_CHAIN (specs);
9471 for (i = 0; i < len; ++i)
9474 spec = TREE_VEC_ELT (expanded_specs, i);
9476 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
9477 if (spec == error_mark_node)
9479 new_specs = add_exception_specifier (new_specs, spec,
9483 specs = TREE_CHAIN (specs);
9489 /* Take the tree structure T and replace template parameters used
9490 therein with the argument vector ARGS. IN_DECL is an associated
9491 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
9492 Issue error and warning messages under control of COMPLAIN. Note
9493 that we must be relatively non-tolerant of extensions here, in
9494 order to preserve conformance; if we allow substitutions that
9495 should not be allowed, we may allow argument deductions that should
9496 not succeed, and therefore report ambiguous overload situations
9497 where there are none. In theory, we could allow the substitution,
9498 but indicate that it should have failed, and allow our caller to
9499 make sure that the right thing happens, but we don't try to do this
9502 This function is used for dealing with types, decls and the like;
9503 for expressions, use tsubst_expr or tsubst_copy. */
9506 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9510 if (t == NULL_TREE || t == error_mark_node
9511 || t == integer_type_node
9512 || t == void_type_node
9513 || t == char_type_node
9514 || t == unknown_type_node
9515 || TREE_CODE (t) == NAMESPACE_DECL)
9519 return tsubst_decl (t, args, complain);
9521 if (args == NULL_TREE)
9524 if (TREE_CODE (t) == IDENTIFIER_NODE)
9525 type = IDENTIFIER_TYPE_VALUE (t);
9527 type = TREE_TYPE (t);
9529 gcc_assert (type != unknown_type_node);
9531 /* Reuse typedefs. We need to do this to handle dependent attributes,
9532 such as attribute aligned. */
9535 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
9537 tree decl = TYPE_NAME (t);
9539 if (DECL_CLASS_SCOPE_P (decl)
9540 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
9541 && uses_template_parms (DECL_CONTEXT (decl)))
9543 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
9544 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
9545 r = retrieve_specialization (tmpl, gen_args, 0);
9547 else if (DECL_FUNCTION_SCOPE_P (decl)
9548 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
9549 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
9550 r = retrieve_local_specialization (decl);
9552 /* The typedef is from a non-template context. */
9558 r = cp_build_qualified_type_real
9559 (r, cp_type_quals (t) | cp_type_quals (r),
9560 complain | tf_ignore_bad_quals);
9563 /* Else we must be instantiating the typedef, so fall through. */
9567 && TREE_CODE (t) != TYPENAME_TYPE
9568 && TREE_CODE (t) != IDENTIFIER_NODE
9569 && TREE_CODE (t) != FUNCTION_TYPE
9570 && TREE_CODE (t) != METHOD_TYPE)
9571 type = tsubst (type, args, complain, in_decl);
9572 if (type == error_mark_node)
9573 return error_mark_node;
9575 switch (TREE_CODE (t))
9580 return tsubst_aggr_type (t, args, complain, in_decl,
9581 /*entering_scope=*/0);
9584 case IDENTIFIER_NODE:
9596 if (t == integer_type_node)
9599 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
9600 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
9604 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
9606 max = tsubst_expr (omax, args, complain, in_decl,
9607 /*integral_constant_expression_p=*/false);
9609 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
9611 if (TREE_CODE (max) == NOP_EXPR
9612 && TREE_SIDE_EFFECTS (omax)
9613 && !TREE_TYPE (max))
9614 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
9616 max = fold_decl_constant_value (max);
9618 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
9619 with TREE_SIDE_EFFECTS that indicates this is not an integral
9620 constant expression. */
9621 if (processing_template_decl
9622 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
9624 gcc_assert (TREE_CODE (max) == NOP_EXPR);
9625 TREE_SIDE_EFFECTS (max) = 1;
9628 if (TREE_CODE (max) != INTEGER_CST
9629 && !at_function_scope_p ()
9630 && !TREE_SIDE_EFFECTS (max)
9631 && !value_dependent_expression_p (max))
9633 if (complain & tf_error)
9634 error ("array bound is not an integer constant");
9635 return error_mark_node;
9640 Type deduction may fail for any of the following
9643 Attempting to create an array with a size that is
9644 zero or negative. */
9645 if (integer_zerop (max) && !(complain & tf_error))
9646 /* We must fail if performing argument deduction (as
9647 indicated by the state of complain), so that
9648 another substitution can be found. */
9649 return error_mark_node;
9650 else if (TREE_CODE (max) == INTEGER_CST
9651 && INT_CST_LT (max, integer_zero_node))
9653 if (complain & tf_error)
9654 error ("creating array with negative size (%qE)", max);
9656 return error_mark_node;
9659 return compute_array_index_type (NULL_TREE, max);
9662 case TEMPLATE_TYPE_PARM:
9663 case TEMPLATE_TEMPLATE_PARM:
9664 case BOUND_TEMPLATE_TEMPLATE_PARM:
9665 case TEMPLATE_PARM_INDEX:
9670 tree arg = NULL_TREE;
9674 gcc_assert (TREE_VEC_LENGTH (args) > 0);
9675 template_parm_level_and_index (t, &level, &idx);
9677 levels = TMPL_ARGS_DEPTH (args);
9678 if (level <= levels)
9680 arg = TMPL_ARG (args, level, idx);
9682 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
9683 /* See through ARGUMENT_PACK_SELECT arguments. */
9684 arg = ARGUMENT_PACK_SELECT_ARG (arg);
9687 if (arg == error_mark_node)
9688 return error_mark_node;
9689 else if (arg != NULL_TREE)
9691 if (ARGUMENT_PACK_P (arg))
9692 /* If ARG is an argument pack, we don't actually want to
9693 perform a substitution here, because substitutions
9694 for argument packs are only done
9695 element-by-element. We can get to this point when
9696 substituting the type of a non-type template
9697 parameter pack, when that type actually contains
9698 template parameter packs from an outer template, e.g.,
9700 template<typename... Types> struct A {
9701 template<Types... Values> struct B { };
9705 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
9708 gcc_assert (TYPE_P (arg));
9710 /* cv-quals from the template are discarded when
9711 substituting in a function or reference type. */
9712 if (TREE_CODE (arg) == FUNCTION_TYPE
9713 || TREE_CODE (arg) == METHOD_TYPE
9714 || TREE_CODE (arg) == REFERENCE_TYPE)
9715 quals = cp_type_quals (arg);
9717 quals = cp_type_quals (arg) | cp_type_quals (t);
9719 return cp_build_qualified_type_real
9720 (arg, quals, complain | tf_ignore_bad_quals);
9722 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9724 /* We are processing a type constructed from a
9725 template template parameter. */
9726 tree argvec = tsubst (TYPE_TI_ARGS (t),
9727 args, complain, in_decl);
9728 if (argvec == error_mark_node)
9729 return error_mark_node;
9731 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
9732 are resolving nested-types in the signature of a
9733 member function templates. Otherwise ARG is a
9734 TEMPLATE_DECL and is the real template to be
9736 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
9737 arg = TYPE_NAME (arg);
9739 r = lookup_template_class (arg,
9742 /*entering_scope=*/0,
9744 return cp_build_qualified_type_real
9745 (r, TYPE_QUALS (t), complain);
9748 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
9753 /* This can happen during the attempted tsubst'ing in
9754 unify. This means that we don't yet have any information
9755 about the template parameter in question. */
9758 /* If we get here, we must have been looking at a parm for a
9759 more deeply nested template. Make a new version of this
9760 template parameter, but with a lower level. */
9761 switch (TREE_CODE (t))
9763 case TEMPLATE_TYPE_PARM:
9764 case TEMPLATE_TEMPLATE_PARM:
9765 case BOUND_TEMPLATE_TEMPLATE_PARM:
9766 if (cp_type_quals (t))
9768 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
9769 r = cp_build_qualified_type_real
9770 (r, cp_type_quals (t),
9771 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
9772 ? tf_ignore_bad_quals : 0));
9777 TEMPLATE_TYPE_PARM_INDEX (r)
9778 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
9779 r, levels, args, complain);
9780 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
9781 TYPE_MAIN_VARIANT (r) = r;
9782 TYPE_POINTER_TO (r) = NULL_TREE;
9783 TYPE_REFERENCE_TO (r) = NULL_TREE;
9785 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
9786 /* We have reduced the level of the template
9787 template parameter, but not the levels of its
9788 template parameters, so canonical_type_parameter
9789 will not be able to find the canonical template
9790 template parameter for this level. Thus, we
9791 require structural equality checking to compare
9792 TEMPLATE_TEMPLATE_PARMs. */
9793 SET_TYPE_STRUCTURAL_EQUALITY (r);
9794 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
9795 SET_TYPE_STRUCTURAL_EQUALITY (r);
9797 TYPE_CANONICAL (r) = canonical_type_parameter (r);
9799 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9801 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
9803 if (argvec == error_mark_node)
9804 return error_mark_node;
9806 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
9807 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
9812 case TEMPLATE_PARM_INDEX:
9813 r = reduce_template_parm_level (t, type, levels, args, complain);
9825 tree purpose, value, chain;
9827 if (t == void_list_node)
9830 purpose = TREE_PURPOSE (t);
9833 purpose = tsubst (purpose, args, complain, in_decl);
9834 if (purpose == error_mark_node)
9835 return error_mark_node;
9837 value = TREE_VALUE (t);
9840 value = tsubst (value, args, complain, in_decl);
9841 if (value == error_mark_node)
9842 return error_mark_node;
9844 chain = TREE_CHAIN (t);
9845 if (chain && chain != void_type_node)
9847 chain = tsubst (chain, args, complain, in_decl);
9848 if (chain == error_mark_node)
9849 return error_mark_node;
9851 if (purpose == TREE_PURPOSE (t)
9852 && value == TREE_VALUE (t)
9853 && chain == TREE_CHAIN (t))
9855 return hash_tree_cons (purpose, value, chain);
9859 /* We should never be tsubsting a binfo. */
9863 /* A vector of template arguments. */
9865 return tsubst_template_args (t, args, complain, in_decl);
9868 case REFERENCE_TYPE:
9870 enum tree_code code;
9872 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
9875 code = TREE_CODE (t);
9880 Type deduction may fail for any of the following
9883 -- Attempting to create a pointer to reference type.
9884 -- Attempting to create a reference to a reference type or
9885 a reference to void.
9887 Core issue 106 says that creating a reference to a reference
9888 during instantiation is no longer a cause for failure. We
9889 only enforce this check in strict C++98 mode. */
9890 if ((TREE_CODE (type) == REFERENCE_TYPE
9891 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
9892 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
9894 static location_t last_loc;
9896 /* We keep track of the last time we issued this error
9897 message to avoid spewing a ton of messages during a
9898 single bad template instantiation. */
9899 if (complain & tf_error
9900 && last_loc != input_location)
9902 if (TREE_CODE (type) == VOID_TYPE)
9903 error ("forming reference to void");
9905 error ("forming %s to reference type %qT",
9906 (code == POINTER_TYPE) ? "pointer" : "reference",
9908 last_loc = input_location;
9911 return error_mark_node;
9913 else if (code == POINTER_TYPE)
9915 r = build_pointer_type (type);
9916 if (TREE_CODE (type) == METHOD_TYPE)
9917 r = build_ptrmemfunc_type (r);
9919 else if (TREE_CODE (type) == REFERENCE_TYPE)
9920 /* In C++0x, during template argument substitution, when there is an
9921 attempt to create a reference to a reference type, reference
9922 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
9924 "If a template-argument for a template-parameter T names a type
9925 that is a reference to a type A, an attempt to create the type
9926 'lvalue reference to cv T' creates the type 'lvalue reference to
9927 A,' while an attempt to create the type type rvalue reference to
9928 cv T' creates the type T"
9930 r = cp_build_reference_type
9932 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
9934 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
9935 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
9937 if (r != error_mark_node)
9938 /* Will this ever be needed for TYPE_..._TO values? */
9945 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
9946 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
9950 Type deduction may fail for any of the following
9953 -- Attempting to create "pointer to member of T" when T
9954 is not a class type. */
9955 if (complain & tf_error)
9956 error ("creating pointer to member of non-class type %qT", r);
9957 return error_mark_node;
9959 if (TREE_CODE (type) == REFERENCE_TYPE)
9961 if (complain & tf_error)
9962 error ("creating pointer to member reference type %qT", type);
9963 return error_mark_node;
9965 if (TREE_CODE (type) == VOID_TYPE)
9967 if (complain & tf_error)
9968 error ("creating pointer to member of type void");
9969 return error_mark_node;
9971 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
9972 if (TREE_CODE (type) == FUNCTION_TYPE)
9974 /* The type of the implicit object parameter gets its
9975 cv-qualifiers from the FUNCTION_TYPE. */
9977 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
9978 cp_type_quals (type));
9980 method_type = build_method_type_directly (this_type,
9982 TYPE_ARG_TYPES (type));
9983 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
9984 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
9988 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
9997 fntype = tsubst_function_type (t, args, complain, in_decl);
9998 if (fntype == error_mark_node)
9999 return error_mark_node;
10001 /* Substitute the exception specification. */
10002 specs = tsubst_exception_specification (t, args, complain,
10004 if (specs == error_mark_node)
10005 return error_mark_node;
10007 fntype = build_exception_variant (fntype, specs);
10012 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
10013 if (domain == error_mark_node)
10014 return error_mark_node;
10016 /* As an optimization, we avoid regenerating the array type if
10017 it will obviously be the same as T. */
10018 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
10021 /* These checks should match the ones in grokdeclarator.
10025 The deduction may fail for any of the following reasons:
10027 -- Attempting to create an array with an element type that
10028 is void, a function type, or a reference type, or [DR337]
10029 an abstract class type. */
10030 if (TREE_CODE (type) == VOID_TYPE
10031 || TREE_CODE (type) == FUNCTION_TYPE
10032 || TREE_CODE (type) == REFERENCE_TYPE)
10034 if (complain & tf_error)
10035 error ("creating array of %qT", type);
10036 return error_mark_node;
10038 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
10040 if (complain & tf_error)
10041 error ("creating array of %qT, which is an abstract class type",
10043 return error_mark_node;
10046 r = build_cplus_array_type (type, domain);
10048 if (TYPE_USER_ALIGN (t))
10050 TYPE_ALIGN (r) = TYPE_ALIGN (t);
10051 TYPE_USER_ALIGN (r) = 1;
10060 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10061 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
10063 if (e1 == error_mark_node || e2 == error_mark_node)
10064 return error_mark_node;
10066 return fold_build2_loc (input_location,
10067 TREE_CODE (t), TREE_TYPE (t), e1, e2);
10073 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10074 if (e == error_mark_node)
10075 return error_mark_node;
10077 return fold_build1_loc (input_location, TREE_CODE (t), TREE_TYPE (t), e);
10080 case TYPENAME_TYPE:
10082 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10083 in_decl, /*entering_scope=*/1);
10084 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
10085 complain, in_decl);
10087 if (ctx == error_mark_node || f == error_mark_node)
10088 return error_mark_node;
10090 if (!MAYBE_CLASS_TYPE_P (ctx))
10092 if (complain & tf_error)
10093 error ("%qT is not a class, struct, or union type", ctx);
10094 return error_mark_node;
10096 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
10098 /* Normally, make_typename_type does not require that the CTX
10099 have complete type in order to allow things like:
10101 template <class T> struct S { typename S<T>::X Y; };
10103 But, such constructs have already been resolved by this
10104 point, so here CTX really should have complete type, unless
10105 it's a partial instantiation. */
10106 if (!(complain & tf_no_class_instantiations))
10107 ctx = complete_type (ctx);
10108 if (!COMPLETE_TYPE_P (ctx))
10110 if (complain & tf_error)
10111 cxx_incomplete_type_error (NULL_TREE, ctx);
10112 return error_mark_node;
10116 f = make_typename_type (ctx, f, typename_type,
10117 (complain & tf_error) | tf_keep_type_decl);
10118 if (f == error_mark_node)
10120 if (TREE_CODE (f) == TYPE_DECL)
10122 complain |= tf_ignore_bad_quals;
10126 if (TREE_CODE (f) != TYPENAME_TYPE)
10128 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
10129 error ("%qT resolves to %qT, which is not an enumeration type",
10131 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
10132 error ("%qT resolves to %qT, which is is not a class type",
10136 return cp_build_qualified_type_real
10137 (f, cp_type_quals (f) | cp_type_quals (t), complain);
10140 case UNBOUND_CLASS_TEMPLATE:
10142 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10143 in_decl, /*entering_scope=*/1);
10144 tree name = TYPE_IDENTIFIER (t);
10145 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
10147 if (ctx == error_mark_node || name == error_mark_node)
10148 return error_mark_node;
10151 parm_list = tsubst_template_parms (parm_list, args, complain);
10152 return make_unbound_class_template (ctx, name, parm_list, complain);
10158 gcc_unreachable ();
10162 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10163 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
10164 /*integral_constant_expression_p=*/false);
10165 if (e1 == error_mark_node || e2 == error_mark_node)
10166 return error_mark_node;
10168 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
10173 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10174 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
10175 if (e1 == error_mark_node || e2 == error_mark_node)
10176 return error_mark_node;
10178 return build_qualified_name (/*type=*/NULL_TREE,
10179 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
10186 type = finish_typeof (tsubst_expr
10187 (TYPEOF_TYPE_EXPR (t), args,
10189 /*integral_constant_expression_p=*/false));
10190 return cp_build_qualified_type_real (type,
10192 | cp_type_quals (type),
10196 case DECLTYPE_TYPE:
10200 ++cp_unevaluated_operand;
10201 ++c_inhibit_evaluation_warnings;
10203 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
10205 /*integral_constant_expression_p=*/false);
10207 --cp_unevaluated_operand;
10208 --c_inhibit_evaluation_warnings;
10210 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
10211 type = lambda_capture_field_type (type);
10212 else if (DECLTYPE_FOR_LAMBDA_RETURN (t))
10213 type = lambda_return_type (type);
10215 type = finish_decltype_type
10216 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
10217 return cp_build_qualified_type_real (type,
10219 | cp_type_quals (type),
10223 case TYPE_ARGUMENT_PACK:
10224 case NONTYPE_ARGUMENT_PACK:
10226 tree r = TYPE_P (t)
10227 ? cxx_make_type (TREE_CODE (t))
10228 : make_node (TREE_CODE (t));
10230 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
10234 SET_ARGUMENT_PACK_ARGS (r, packed_out);
10236 /* For template nontype argument packs, also substitute into
10238 if (TREE_CODE (t) == NONTYPE_ARGUMENT_PACK)
10239 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
10246 sorry ("use of %qs in template",
10247 tree_code_name [(int) TREE_CODE (t)]);
10248 return error_mark_node;
10252 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
10253 type of the expression on the left-hand side of the "." or "->"
10257 tsubst_baselink (tree baselink, tree object_type,
10258 tree args, tsubst_flags_t complain, tree in_decl)
10261 tree qualifying_scope;
10264 tree template_args = 0;
10265 bool template_id_p = false;
10267 /* A baselink indicates a function from a base class. Both the
10268 BASELINK_ACCESS_BINFO and the base class referenced may
10269 indicate bases of the template class, rather than the
10270 instantiated class. In addition, lookups that were not
10271 ambiguous before may be ambiguous now. Therefore, we perform
10272 the lookup again. */
10273 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
10274 qualifying_scope = tsubst (qualifying_scope, args,
10275 complain, in_decl);
10276 fns = BASELINK_FUNCTIONS (baselink);
10277 optype = BASELINK_OPTYPE (baselink);
10278 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
10280 template_id_p = true;
10281 template_args = TREE_OPERAND (fns, 1);
10282 fns = TREE_OPERAND (fns, 0);
10284 template_args = tsubst_template_args (template_args, args,
10285 complain, in_decl);
10287 name = DECL_NAME (get_first_fn (fns));
10288 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
10290 /* If lookup found a single function, mark it as used at this
10291 point. (If it lookup found multiple functions the one selected
10292 later by overload resolution will be marked as used at that
10294 if (BASELINK_P (baselink))
10295 fns = BASELINK_FUNCTIONS (baselink);
10296 if (!template_id_p && !really_overloaded_fn (fns))
10297 mark_used (OVL_CURRENT (fns));
10299 /* Add back the template arguments, if present. */
10300 if (BASELINK_P (baselink) && template_id_p)
10301 BASELINK_FUNCTIONS (baselink)
10302 = build_nt (TEMPLATE_ID_EXPR,
10303 BASELINK_FUNCTIONS (baselink),
10305 /* Update the conversion operator type. */
10306 BASELINK_OPTYPE (baselink)
10307 = tsubst (optype, args, complain, in_decl);
10310 object_type = current_class_type;
10311 return adjust_result_of_qualified_name_lookup (baselink,
10316 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
10317 true if the qualified-id will be a postfix-expression in-and-of
10318 itself; false if more of the postfix-expression follows the
10319 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
10323 tsubst_qualified_id (tree qualified_id, tree args,
10324 tsubst_flags_t complain, tree in_decl,
10325 bool done, bool address_p)
10331 tree template_args;
10333 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
10335 /* Figure out what name to look up. */
10336 name = TREE_OPERAND (qualified_id, 1);
10337 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
10339 is_template = true;
10340 template_args = TREE_OPERAND (name, 1);
10342 template_args = tsubst_template_args (template_args, args,
10343 complain, in_decl);
10344 name = TREE_OPERAND (name, 0);
10348 is_template = false;
10349 template_args = NULL_TREE;
10352 /* Substitute into the qualifying scope. When there are no ARGS, we
10353 are just trying to simplify a non-dependent expression. In that
10354 case the qualifying scope may be dependent, and, in any case,
10355 substituting will not help. */
10356 scope = TREE_OPERAND (qualified_id, 0);
10359 scope = tsubst (scope, args, complain, in_decl);
10360 expr = tsubst_copy (name, args, complain, in_decl);
10365 if (dependent_type_p (scope))
10367 tree type = NULL_TREE;
10368 if (DECL_P (expr) && !dependent_scope_p (scope))
10369 type = TREE_TYPE (expr);
10370 return build_qualified_name (type, scope, expr,
10371 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
10374 if (!BASELINK_P (name) && !DECL_P (expr))
10376 if (TREE_CODE (expr) == BIT_NOT_EXPR)
10378 /* A BIT_NOT_EXPR is used to represent a destructor. */
10379 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
10381 error ("qualifying type %qT does not match destructor name ~%qT",
10382 scope, TREE_OPERAND (expr, 0));
10383 expr = error_mark_node;
10386 expr = lookup_qualified_name (scope, complete_dtor_identifier,
10387 /*is_type_p=*/0, false);
10390 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
10391 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
10392 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
10394 if (complain & tf_error)
10396 error ("dependent-name %qE is parsed as a non-type, but "
10397 "instantiation yields a type", qualified_id);
10398 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
10400 return error_mark_node;
10406 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
10408 /* Remember that there was a reference to this entity. */
10412 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
10414 if (complain & tf_error)
10415 qualified_name_lookup_error (scope,
10416 TREE_OPERAND (qualified_id, 1),
10417 expr, input_location);
10418 return error_mark_node;
10422 expr = lookup_template_function (expr, template_args);
10424 if (expr == error_mark_node && complain & tf_error)
10425 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
10426 expr, input_location);
10427 else if (TYPE_P (scope))
10429 expr = (adjust_result_of_qualified_name_lookup
10430 (expr, scope, current_class_type));
10431 expr = (finish_qualified_id_expr
10432 (scope, expr, done, address_p,
10433 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
10434 /*template_arg_p=*/false));
10437 /* Expressions do not generally have reference type. */
10438 if (TREE_CODE (expr) != SCOPE_REF
10439 /* However, if we're about to form a pointer-to-member, we just
10440 want the referenced member referenced. */
10441 && TREE_CODE (expr) != OFFSET_REF)
10442 expr = convert_from_reference (expr);
10447 /* Like tsubst, but deals with expressions. This function just replaces
10448 template parms; to finish processing the resultant expression, use
10452 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10454 enum tree_code code;
10457 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
10460 code = TREE_CODE (t);
10465 r = retrieve_local_specialization (t);
10470 /* This can happen for a parameter name used later in a function
10471 declaration (such as in a late-specified return type). Just
10472 make a dummy decl, since it's only used for its type. */
10473 gcc_assert (cp_unevaluated_operand != 0);
10474 /* We copy T because want to tsubst the PARM_DECL only,
10475 not the following PARM_DECLs that are chained to T. */
10477 r = tsubst_decl (c, args, complain);
10478 /* Give it the template pattern as its context; its true context
10479 hasn't been instantiated yet and this is good enough for
10481 DECL_CONTEXT (r) = DECL_CONTEXT (t);
10484 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
10485 r = ARGUMENT_PACK_SELECT_ARG (r);
10494 if (DECL_TEMPLATE_PARM_P (t))
10495 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
10496 /* There is no need to substitute into namespace-scope
10498 if (DECL_NAMESPACE_SCOPE_P (t))
10500 /* If ARGS is NULL, then T is known to be non-dependent. */
10501 if (args == NULL_TREE)
10502 return integral_constant_value (t);
10504 /* Unfortunately, we cannot just call lookup_name here.
10507 template <int I> int f() {
10509 struct S { void g() { E e = a; } };
10512 When we instantiate f<7>::S::g(), say, lookup_name is not
10513 clever enough to find f<7>::a. */
10515 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
10516 /*entering_scope=*/0);
10518 for (v = TYPE_VALUES (enum_type);
10520 v = TREE_CHAIN (v))
10521 if (TREE_PURPOSE (v) == DECL_NAME (t))
10522 return TREE_VALUE (v);
10524 /* We didn't find the name. That should never happen; if
10525 name-lookup found it during preliminary parsing, we
10526 should find it again here during instantiation. */
10527 gcc_unreachable ();
10532 if (DECL_CONTEXT (t))
10536 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
10537 /*entering_scope=*/1);
10538 if (ctx != DECL_CONTEXT (t))
10540 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
10543 if (complain & tf_error)
10544 error ("using invalid field %qD", t);
10545 return error_mark_node;
10554 case FUNCTION_DECL:
10555 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
10556 || local_variable_p (t))
10557 t = tsubst (t, args, complain, in_decl);
10562 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
10564 case TEMPLATE_DECL:
10565 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
10566 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
10567 args, complain, in_decl);
10568 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
10569 return tsubst (t, args, complain, in_decl);
10570 else if (DECL_CLASS_SCOPE_P (t)
10571 && uses_template_parms (DECL_CONTEXT (t)))
10573 /* Template template argument like the following example need
10576 template <template <class> class TT> struct C {};
10577 template <class T> struct D {
10578 template <class U> struct E {};
10583 We are processing the template argument `E' in #1 for
10584 the template instantiation #2. Originally, `E' is a
10585 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
10586 have to substitute this with one having context `D<int>'. */
10588 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
10589 return lookup_field (context, DECL_NAME(t), 0, false);
10592 /* Ordinary template template argument. */
10596 case REINTERPRET_CAST_EXPR:
10597 case CONST_CAST_EXPR:
10598 case STATIC_CAST_EXPR:
10599 case DYNAMIC_CAST_EXPR:
10602 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10603 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10606 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
10608 /* We only want to compute the number of arguments. */
10609 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
10610 complain, in_decl);
10613 if (TREE_CODE (expanded) == TREE_VEC)
10614 len = TREE_VEC_LENGTH (expanded);
10616 if (expanded == error_mark_node)
10617 return error_mark_node;
10618 else if (PACK_EXPANSION_P (expanded)
10619 || (TREE_CODE (expanded) == TREE_VEC
10621 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
10623 if (TREE_CODE (expanded) == TREE_VEC)
10624 expanded = TREE_VEC_ELT (expanded, len - 1);
10626 if (TYPE_P (expanded))
10627 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
10628 complain & tf_error);
10630 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
10631 complain & tf_error);
10634 return build_int_cst (size_type_node, len);
10640 case TRUTH_NOT_EXPR:
10643 case UNARY_PLUS_EXPR: /* Unary + */
10648 case REALPART_EXPR:
10649 case IMAGPART_EXPR:
10651 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10652 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10654 case COMPONENT_REF:
10659 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
10660 name = TREE_OPERAND (t, 1);
10661 if (TREE_CODE (name) == BIT_NOT_EXPR)
10663 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10664 complain, in_decl);
10665 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10667 else if (TREE_CODE (name) == SCOPE_REF
10668 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
10670 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
10671 complain, in_decl);
10672 name = TREE_OPERAND (name, 1);
10673 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10674 complain, in_decl);
10675 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10676 name = build_qualified_name (/*type=*/NULL_TREE,
10678 /*template_p=*/false);
10680 else if (TREE_CODE (name) == BASELINK)
10681 name = tsubst_baselink (name,
10682 non_reference (TREE_TYPE (object)),
10686 name = tsubst_copy (name, args, complain, in_decl);
10687 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
10693 case TRUNC_DIV_EXPR:
10694 case CEIL_DIV_EXPR:
10695 case FLOOR_DIV_EXPR:
10696 case ROUND_DIV_EXPR:
10697 case EXACT_DIV_EXPR:
10701 case TRUNC_MOD_EXPR:
10702 case FLOOR_MOD_EXPR:
10703 case TRUTH_ANDIF_EXPR:
10704 case TRUTH_ORIF_EXPR:
10705 case TRUTH_AND_EXPR:
10706 case TRUTH_OR_EXPR:
10719 case COMPOUND_EXPR:
10722 case PREDECREMENT_EXPR:
10723 case PREINCREMENT_EXPR:
10724 case POSTDECREMENT_EXPR:
10725 case POSTINCREMENT_EXPR:
10727 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10728 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10731 return build_qualified_name (/*type=*/NULL_TREE,
10732 tsubst_copy (TREE_OPERAND (t, 0),
10733 args, complain, in_decl),
10734 tsubst_copy (TREE_OPERAND (t, 1),
10735 args, complain, in_decl),
10736 QUALIFIED_NAME_IS_TEMPLATE (t));
10741 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10742 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10743 NULL_TREE, NULL_TREE);
10747 int n = VL_EXP_OPERAND_LENGTH (t);
10748 tree result = build_vl_exp (CALL_EXPR, n);
10750 for (i = 0; i < n; i++)
10751 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
10752 complain, in_decl);
10758 case PSEUDO_DTOR_EXPR:
10761 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10762 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10763 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10764 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
10771 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10772 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10773 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10774 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
10781 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10782 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10783 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
10784 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
10788 case TEMPLATE_ID_EXPR:
10790 /* Substituted template arguments */
10791 tree fn = TREE_OPERAND (t, 0);
10792 tree targs = TREE_OPERAND (t, 1);
10794 fn = tsubst_copy (fn, args, complain, in_decl);
10796 targs = tsubst_template_args (targs, args, complain, in_decl);
10798 return lookup_template_function (fn, targs);
10803 tree purpose, value, chain;
10805 if (t == void_list_node)
10808 purpose = TREE_PURPOSE (t);
10810 purpose = tsubst_copy (purpose, args, complain, in_decl);
10811 value = TREE_VALUE (t);
10813 value = tsubst_copy (value, args, complain, in_decl);
10814 chain = TREE_CHAIN (t);
10815 if (chain && chain != void_type_node)
10816 chain = tsubst_copy (chain, args, complain, in_decl);
10817 if (purpose == TREE_PURPOSE (t)
10818 && value == TREE_VALUE (t)
10819 && chain == TREE_CHAIN (t))
10821 return tree_cons (purpose, value, chain);
10826 case ENUMERAL_TYPE:
10828 case TEMPLATE_TYPE_PARM:
10829 case TEMPLATE_TEMPLATE_PARM:
10830 case BOUND_TEMPLATE_TEMPLATE_PARM:
10831 case TEMPLATE_PARM_INDEX:
10833 case REFERENCE_TYPE:
10835 case FUNCTION_TYPE:
10838 case TYPENAME_TYPE:
10839 case UNBOUND_CLASS_TEMPLATE:
10841 case DECLTYPE_TYPE:
10843 return tsubst (t, args, complain, in_decl);
10845 case IDENTIFIER_NODE:
10846 if (IDENTIFIER_TYPENAME_P (t))
10848 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10849 return mangle_conv_op_name_for_type (new_type);
10855 /* This is handled by tsubst_copy_and_build. */
10856 gcc_unreachable ();
10859 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
10861 tsubst (TREE_TYPE (t), args, complain, in_decl));
10863 case CLEANUP_POINT_EXPR:
10864 /* We shouldn't have built any of these during initial template
10865 generation. Instead, they should be built during instantiation
10866 in response to the saved STMT_IS_FULL_EXPR_P setting. */
10867 gcc_unreachable ();
10870 mark_used (TREE_OPERAND (t, 1));
10873 case EXPR_PACK_EXPANSION:
10874 error ("invalid use of pack expansion expression");
10875 return error_mark_node;
10877 case NONTYPE_ARGUMENT_PACK:
10878 error ("use %<...%> to expand argument pack");
10879 return error_mark_node;
10886 /* Like tsubst_copy, but specifically for OpenMP clauses. */
10889 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
10892 tree new_clauses = NULL, nc, oc;
10894 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
10896 nc = copy_node (oc);
10897 OMP_CLAUSE_CHAIN (nc) = new_clauses;
10900 switch (OMP_CLAUSE_CODE (nc))
10902 case OMP_CLAUSE_LASTPRIVATE:
10903 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
10905 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
10906 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
10907 in_decl, /*integral_constant_expression_p=*/false);
10908 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
10909 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
10912 case OMP_CLAUSE_PRIVATE:
10913 case OMP_CLAUSE_SHARED:
10914 case OMP_CLAUSE_FIRSTPRIVATE:
10915 case OMP_CLAUSE_REDUCTION:
10916 case OMP_CLAUSE_COPYIN:
10917 case OMP_CLAUSE_COPYPRIVATE:
10918 case OMP_CLAUSE_IF:
10919 case OMP_CLAUSE_NUM_THREADS:
10920 case OMP_CLAUSE_SCHEDULE:
10921 case OMP_CLAUSE_COLLAPSE:
10922 OMP_CLAUSE_OPERAND (nc, 0)
10923 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
10924 in_decl, /*integral_constant_expression_p=*/false);
10926 case OMP_CLAUSE_NOWAIT:
10927 case OMP_CLAUSE_ORDERED:
10928 case OMP_CLAUSE_DEFAULT:
10929 case OMP_CLAUSE_UNTIED:
10932 gcc_unreachable ();
10936 return finish_omp_clauses (nreverse (new_clauses));
10939 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
10942 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
10945 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
10947 tree purpose, value, chain;
10952 if (TREE_CODE (t) != TREE_LIST)
10953 return tsubst_copy_and_build (t, args, complain, in_decl,
10954 /*function_p=*/false,
10955 /*integral_constant_expression_p=*/false);
10957 if (t == void_list_node)
10960 purpose = TREE_PURPOSE (t);
10962 purpose = RECUR (purpose);
10963 value = TREE_VALUE (t);
10964 if (value && TREE_CODE (value) != LABEL_DECL)
10965 value = RECUR (value);
10966 chain = TREE_CHAIN (t);
10967 if (chain && chain != void_type_node)
10968 chain = RECUR (chain);
10969 return tree_cons (purpose, value, chain);
10973 /* Substitute one OMP_FOR iterator. */
10976 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
10977 tree condv, tree incrv, tree *clauses,
10978 tree args, tsubst_flags_t complain, tree in_decl,
10979 bool integral_constant_expression_p)
10981 #define RECUR(NODE) \
10982 tsubst_expr ((NODE), args, complain, in_decl, \
10983 integral_constant_expression_p)
10984 tree decl, init, cond, incr, auto_node;
10986 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
10987 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
10988 decl = RECUR (TREE_OPERAND (init, 0));
10989 init = TREE_OPERAND (init, 1);
10990 auto_node = type_uses_auto (TREE_TYPE (decl));
10991 if (auto_node && init)
10993 tree init_expr = init;
10994 if (TREE_CODE (init_expr) == DECL_EXPR)
10995 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
10996 init_expr = RECUR (init_expr);
10998 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
11000 gcc_assert (!type_dependent_expression_p (decl));
11002 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
11004 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
11005 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11006 if (TREE_CODE (incr) == MODIFY_EXPR)
11007 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
11008 RECUR (TREE_OPERAND (incr, 1)),
11011 incr = RECUR (incr);
11012 TREE_VEC_ELT (declv, i) = decl;
11013 TREE_VEC_ELT (initv, i) = init;
11014 TREE_VEC_ELT (condv, i) = cond;
11015 TREE_VEC_ELT (incrv, i) = incr;
11019 if (init && TREE_CODE (init) != DECL_EXPR)
11022 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
11024 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
11025 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
11026 && OMP_CLAUSE_DECL (c) == decl)
11028 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
11029 && OMP_CLAUSE_DECL (c) == decl)
11030 error ("iteration variable %qD should not be firstprivate", decl);
11031 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
11032 && OMP_CLAUSE_DECL (c) == decl)
11033 error ("iteration variable %qD should not be reduction", decl);
11037 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
11038 OMP_CLAUSE_DECL (c) = decl;
11039 c = finish_omp_clauses (c);
11042 OMP_CLAUSE_CHAIN (c) = *clauses;
11047 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
11048 if (COMPARISON_CLASS_P (cond))
11049 cond = build2 (TREE_CODE (cond), boolean_type_node,
11050 RECUR (TREE_OPERAND (cond, 0)),
11051 RECUR (TREE_OPERAND (cond, 1)));
11053 cond = RECUR (cond);
11054 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11055 switch (TREE_CODE (incr))
11057 case PREINCREMENT_EXPR:
11058 case PREDECREMENT_EXPR:
11059 case POSTINCREMENT_EXPR:
11060 case POSTDECREMENT_EXPR:
11061 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
11062 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
11065 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11066 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11068 tree rhs = TREE_OPERAND (incr, 1);
11069 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11070 RECUR (TREE_OPERAND (incr, 0)),
11071 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11072 RECUR (TREE_OPERAND (rhs, 0)),
11073 RECUR (TREE_OPERAND (rhs, 1))));
11076 incr = RECUR (incr);
11079 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11080 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11082 tree lhs = RECUR (TREE_OPERAND (incr, 0));
11083 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
11084 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
11085 TREE_TYPE (decl), lhs,
11086 RECUR (TREE_OPERAND (incr, 2))));
11088 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
11089 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
11090 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
11092 tree rhs = TREE_OPERAND (incr, 2);
11093 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11094 RECUR (TREE_OPERAND (incr, 0)),
11095 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11096 RECUR (TREE_OPERAND (rhs, 0)),
11097 RECUR (TREE_OPERAND (rhs, 1))));
11100 incr = RECUR (incr);
11103 incr = RECUR (incr);
11107 TREE_VEC_ELT (declv, i) = decl;
11108 TREE_VEC_ELT (initv, i) = init;
11109 TREE_VEC_ELT (condv, i) = cond;
11110 TREE_VEC_ELT (incrv, i) = incr;
11114 /* Like tsubst_copy for expressions, etc. but also does semantic
11118 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
11119 bool integral_constant_expression_p)
11121 #define RECUR(NODE) \
11122 tsubst_expr ((NODE), args, complain, in_decl, \
11123 integral_constant_expression_p)
11127 if (t == NULL_TREE || t == error_mark_node)
11130 if (EXPR_HAS_LOCATION (t))
11131 input_location = EXPR_LOCATION (t);
11132 if (STATEMENT_CODE_P (TREE_CODE (t)))
11133 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
11135 switch (TREE_CODE (t))
11137 case STATEMENT_LIST:
11139 tree_stmt_iterator i;
11140 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
11141 RECUR (tsi_stmt (i));
11145 case CTOR_INITIALIZER:
11146 finish_mem_initializers (tsubst_initializer_list
11147 (TREE_OPERAND (t, 0), args));
11151 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
11155 tmp = RECUR (EXPR_STMT_EXPR (t));
11156 if (EXPR_STMT_STMT_EXPR_RESULT (t))
11157 finish_stmt_expr_expr (tmp, cur_stmt_expr);
11159 finish_expr_stmt (tmp);
11163 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
11171 decl = DECL_EXPR_DECL (t);
11172 if (TREE_CODE (decl) == LABEL_DECL)
11173 finish_label_decl (DECL_NAME (decl));
11174 else if (TREE_CODE (decl) == USING_DECL)
11176 tree scope = USING_DECL_SCOPE (decl);
11177 tree name = DECL_NAME (decl);
11180 scope = RECUR (scope);
11181 decl = lookup_qualified_name (scope, name,
11182 /*is_type_p=*/false,
11183 /*complain=*/false);
11184 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
11185 qualified_name_lookup_error (scope, name, decl, input_location);
11187 do_local_using_decl (decl, scope, name);
11191 init = DECL_INITIAL (decl);
11192 decl = tsubst (decl, args, complain, in_decl);
11193 if (decl != error_mark_node)
11195 /* By marking the declaration as instantiated, we avoid
11196 trying to instantiate it. Since instantiate_decl can't
11197 handle local variables, and since we've already done
11198 all that needs to be done, that's the right thing to
11200 if (TREE_CODE (decl) == VAR_DECL)
11201 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11202 if (TREE_CODE (decl) == VAR_DECL
11203 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
11204 /* Anonymous aggregates are a special case. */
11205 finish_anon_union (decl);
11208 maybe_push_decl (decl);
11209 if (TREE_CODE (decl) == VAR_DECL
11210 && DECL_PRETTY_FUNCTION_P (decl))
11212 /* For __PRETTY_FUNCTION__ we have to adjust the
11214 const char *const name
11215 = cxx_printable_name (current_function_decl, 2);
11216 init = cp_fname_init (name, &TREE_TYPE (decl));
11220 tree t = RECUR (init);
11223 /* If we had an initializer but it
11224 instantiated to nothing,
11225 value-initialize the object. This will
11226 only occur when the initializer was a
11227 pack expansion where the parameter packs
11228 used in that expansion were of length
11230 init = build_value_init (TREE_TYPE (decl));
11235 cp_finish_decl (decl, init, false, NULL_TREE, 0);
11240 /* A DECL_EXPR can also be used as an expression, in the condition
11241 clause of an if/for/while construct. */
11246 stmt = begin_for_stmt ();
11247 RECUR (FOR_INIT_STMT (t));
11248 finish_for_init_stmt (stmt);
11249 tmp = RECUR (FOR_COND (t));
11250 finish_for_cond (tmp, stmt);
11251 tmp = RECUR (FOR_EXPR (t));
11252 finish_for_expr (tmp, stmt);
11253 RECUR (FOR_BODY (t));
11254 finish_for_stmt (stmt);
11258 stmt = begin_while_stmt ();
11259 tmp = RECUR (WHILE_COND (t));
11260 finish_while_stmt_cond (tmp, stmt);
11261 RECUR (WHILE_BODY (t));
11262 finish_while_stmt (stmt);
11266 stmt = begin_do_stmt ();
11267 RECUR (DO_BODY (t));
11268 finish_do_body (stmt);
11269 tmp = RECUR (DO_COND (t));
11270 finish_do_stmt (tmp, stmt);
11274 stmt = begin_if_stmt ();
11275 tmp = RECUR (IF_COND (t));
11276 finish_if_stmt_cond (tmp, stmt);
11277 RECUR (THEN_CLAUSE (t));
11278 finish_then_clause (stmt);
11280 if (ELSE_CLAUSE (t))
11282 begin_else_clause (stmt);
11283 RECUR (ELSE_CLAUSE (t));
11284 finish_else_clause (stmt);
11287 finish_if_stmt (stmt);
11291 if (BIND_EXPR_BODY_BLOCK (t))
11292 stmt = begin_function_body ();
11294 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
11295 ? BCS_TRY_BLOCK : 0);
11297 RECUR (BIND_EXPR_BODY (t));
11299 if (BIND_EXPR_BODY_BLOCK (t))
11300 finish_function_body (stmt);
11302 finish_compound_stmt (stmt);
11306 finish_break_stmt ();
11309 case CONTINUE_STMT:
11310 finish_continue_stmt ();
11314 stmt = begin_switch_stmt ();
11315 tmp = RECUR (SWITCH_STMT_COND (t));
11316 finish_switch_cond (tmp, stmt);
11317 RECUR (SWITCH_STMT_BODY (t));
11318 finish_switch_stmt (stmt);
11321 case CASE_LABEL_EXPR:
11322 finish_case_label (EXPR_LOCATION (t),
11323 RECUR (CASE_LOW (t)),
11324 RECUR (CASE_HIGH (t)));
11329 tree decl = LABEL_EXPR_LABEL (t);
11332 label = finish_label_stmt (DECL_NAME (decl));
11333 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
11334 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
11339 tmp = GOTO_DESTINATION (t);
11340 if (TREE_CODE (tmp) != LABEL_DECL)
11341 /* Computed goto's must be tsubst'd into. On the other hand,
11342 non-computed gotos must not be; the identifier in question
11343 will have no binding. */
11346 tmp = DECL_NAME (tmp);
11347 finish_goto_stmt (tmp);
11351 tmp = finish_asm_stmt
11352 (ASM_VOLATILE_P (t),
11353 RECUR (ASM_STRING (t)),
11354 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
11355 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
11356 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
11357 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
11359 tree asm_expr = tmp;
11360 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
11361 asm_expr = TREE_OPERAND (asm_expr, 0);
11362 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
11369 stmt = begin_try_block ();
11370 RECUR (TRY_STMTS (t));
11371 finish_cleanup_try_block (stmt);
11372 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
11376 tree compound_stmt = NULL_TREE;
11378 if (FN_TRY_BLOCK_P (t))
11379 stmt = begin_function_try_block (&compound_stmt);
11381 stmt = begin_try_block ();
11383 RECUR (TRY_STMTS (t));
11385 if (FN_TRY_BLOCK_P (t))
11386 finish_function_try_block (stmt);
11388 finish_try_block (stmt);
11390 RECUR (TRY_HANDLERS (t));
11391 if (FN_TRY_BLOCK_P (t))
11392 finish_function_handler_sequence (stmt, compound_stmt);
11394 finish_handler_sequence (stmt);
11400 tree decl = HANDLER_PARMS (t);
11404 decl = tsubst (decl, args, complain, in_decl);
11405 /* Prevent instantiate_decl from trying to instantiate
11406 this variable. We've already done all that needs to be
11408 if (decl != error_mark_node)
11409 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11411 stmt = begin_handler ();
11412 finish_handler_parms (decl, stmt);
11413 RECUR (HANDLER_BODY (t));
11414 finish_handler (stmt);
11419 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
11422 case STATIC_ASSERT:
11425 tsubst_expr (STATIC_ASSERT_CONDITION (t),
11428 /*integral_constant_expression_p=*/true);
11429 finish_static_assert (condition,
11430 STATIC_ASSERT_MESSAGE (t),
11431 STATIC_ASSERT_SOURCE_LOCATION (t),
11432 /*member_p=*/false);
11437 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
11438 args, complain, in_decl);
11439 stmt = begin_omp_parallel ();
11440 RECUR (OMP_PARALLEL_BODY (t));
11441 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
11442 = OMP_PARALLEL_COMBINED (t);
11446 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
11447 args, complain, in_decl);
11448 stmt = begin_omp_task ();
11449 RECUR (OMP_TASK_BODY (t));
11450 finish_omp_task (tmp, stmt);
11455 tree clauses, body, pre_body;
11456 tree declv, initv, condv, incrv;
11459 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
11460 args, complain, in_decl);
11461 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11462 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11463 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11464 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11466 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
11467 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
11468 &clauses, args, complain, in_decl,
11469 integral_constant_expression_p);
11471 stmt = begin_omp_structured_block ();
11473 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
11474 if (TREE_VEC_ELT (initv, i) == NULL
11475 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
11476 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
11477 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
11479 tree init = RECUR (TREE_VEC_ELT (initv, i));
11480 gcc_assert (init == TREE_VEC_ELT (declv, i));
11481 TREE_VEC_ELT (initv, i) = NULL_TREE;
11485 tree decl_expr = TREE_VEC_ELT (initv, i);
11486 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
11487 gcc_assert (init != NULL);
11488 TREE_VEC_ELT (initv, i) = RECUR (init);
11489 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
11491 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
11494 pre_body = push_stmt_list ();
11495 RECUR (OMP_FOR_PRE_BODY (t));
11496 pre_body = pop_stmt_list (pre_body);
11498 body = push_stmt_list ();
11499 RECUR (OMP_FOR_BODY (t));
11500 body = pop_stmt_list (body);
11502 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
11503 body, pre_body, clauses);
11505 add_stmt (finish_omp_structured_block (stmt));
11511 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
11512 stmt = push_stmt_list ();
11513 RECUR (OMP_BODY (t));
11514 stmt = pop_stmt_list (stmt);
11517 OMP_BODY (t) = stmt;
11518 OMP_CLAUSES (t) = tmp;
11526 stmt = push_stmt_list ();
11527 RECUR (OMP_BODY (t));
11528 stmt = pop_stmt_list (stmt);
11531 OMP_BODY (t) = stmt;
11536 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
11538 tree op1 = TREE_OPERAND (t, 1);
11539 tree lhs = RECUR (TREE_OPERAND (op1, 0));
11540 tree rhs = RECUR (TREE_OPERAND (op1, 1));
11541 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
11545 case EXPR_PACK_EXPANSION:
11546 error ("invalid use of pack expansion expression");
11547 return error_mark_node;
11549 case NONTYPE_ARGUMENT_PACK:
11550 error ("use %<...%> to expand argument pack");
11551 return error_mark_node;
11554 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
11556 return tsubst_copy_and_build (t, args, complain, in_decl,
11557 /*function_p=*/false,
11558 integral_constant_expression_p);
11565 /* T is a postfix-expression that is not being used in a function
11566 call. Return the substituted version of T. */
11569 tsubst_non_call_postfix_expression (tree t, tree args,
11570 tsubst_flags_t complain,
11573 if (TREE_CODE (t) == SCOPE_REF)
11574 t = tsubst_qualified_id (t, args, complain, in_decl,
11575 /*done=*/false, /*address_p=*/false);
11577 t = tsubst_copy_and_build (t, args, complain, in_decl,
11578 /*function_p=*/false,
11579 /*integral_constant_expression_p=*/false);
11584 /* Like tsubst but deals with expressions and performs semantic
11585 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
11588 tsubst_copy_and_build (tree t,
11590 tsubst_flags_t complain,
11593 bool integral_constant_expression_p)
11595 #define RECUR(NODE) \
11596 tsubst_copy_and_build (NODE, args, complain, in_decl, \
11597 /*function_p=*/false, \
11598 integral_constant_expression_p)
11602 if (t == NULL_TREE || t == error_mark_node)
11605 switch (TREE_CODE (t))
11609 /* Fall through. */
11610 case IDENTIFIER_NODE:
11614 bool non_integral_constant_expression_p;
11615 const char *error_msg;
11617 if (IDENTIFIER_TYPENAME_P (t))
11619 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11620 t = mangle_conv_op_name_for_type (new_type);
11623 /* Look up the name. */
11624 decl = lookup_name (t);
11626 /* By convention, expressions use ERROR_MARK_NODE to indicate
11627 failure, not NULL_TREE. */
11628 if (decl == NULL_TREE)
11629 decl = error_mark_node;
11631 decl = finish_id_expression (t, decl, NULL_TREE,
11633 integral_constant_expression_p,
11634 /*allow_non_integral_constant_expression_p=*/false,
11635 &non_integral_constant_expression_p,
11636 /*template_p=*/false,
11638 /*address_p=*/false,
11639 /*template_arg_p=*/false,
11644 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
11645 decl = unqualified_name_lookup_error (decl);
11649 case TEMPLATE_ID_EXPR:
11652 tree templ = RECUR (TREE_OPERAND (t, 0));
11653 tree targs = TREE_OPERAND (t, 1);
11656 targs = tsubst_template_args (targs, args, complain, in_decl);
11658 if (TREE_CODE (templ) == COMPONENT_REF)
11660 object = TREE_OPERAND (templ, 0);
11661 templ = TREE_OPERAND (templ, 1);
11664 object = NULL_TREE;
11665 templ = lookup_template_function (templ, targs);
11668 return build3 (COMPONENT_REF, TREE_TYPE (templ),
11669 object, templ, NULL_TREE);
11671 return baselink_for_fns (templ);
11676 tree r = RECUR (TREE_OPERAND (t, 0));
11678 if (REFERENCE_REF_P (t))
11680 /* A type conversion to reference type will be enclosed in
11681 such an indirect ref, but the substitution of the cast
11682 will have also added such an indirect ref. */
11683 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
11684 r = convert_from_reference (r);
11687 r = build_x_indirect_ref (r, "unary *", complain);
11693 (tsubst (TREE_TYPE (t), args, complain, in_decl),
11694 RECUR (TREE_OPERAND (t, 0)));
11697 case REINTERPRET_CAST_EXPR:
11698 case CONST_CAST_EXPR:
11699 case DYNAMIC_CAST_EXPR:
11700 case STATIC_CAST_EXPR:
11705 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11706 if (integral_constant_expression_p
11707 && !cast_valid_in_integral_constant_expression_p (type))
11709 if (complain & tf_error)
11710 error ("a cast to a type other than an integral or "
11711 "enumeration type cannot appear in a constant-expression");
11712 return error_mark_node;
11715 op = RECUR (TREE_OPERAND (t, 0));
11717 switch (TREE_CODE (t))
11720 return build_functional_cast (type, op, complain);
11721 case REINTERPRET_CAST_EXPR:
11722 return build_reinterpret_cast (type, op, complain);
11723 case CONST_CAST_EXPR:
11724 return build_const_cast (type, op, complain);
11725 case DYNAMIC_CAST_EXPR:
11726 return build_dynamic_cast (type, op, complain);
11727 case STATIC_CAST_EXPR:
11728 return build_static_cast (type, op, complain);
11730 gcc_unreachable ();
11734 case POSTDECREMENT_EXPR:
11735 case POSTINCREMENT_EXPR:
11736 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11737 args, complain, in_decl);
11738 return build_x_unary_op (TREE_CODE (t), op1, complain);
11740 case PREDECREMENT_EXPR:
11741 case PREINCREMENT_EXPR:
11745 case TRUTH_NOT_EXPR:
11746 case UNARY_PLUS_EXPR: /* Unary + */
11747 case REALPART_EXPR:
11748 case IMAGPART_EXPR:
11749 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
11753 op1 = TREE_OPERAND (t, 0);
11754 if (TREE_CODE (op1) == SCOPE_REF)
11755 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
11756 /*done=*/true, /*address_p=*/true);
11758 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
11760 if (TREE_CODE (op1) == LABEL_DECL)
11761 return finish_label_address_expr (DECL_NAME (op1),
11762 EXPR_LOCATION (op1));
11763 return build_x_unary_op (ADDR_EXPR, op1, complain);
11768 case TRUNC_DIV_EXPR:
11769 case CEIL_DIV_EXPR:
11770 case FLOOR_DIV_EXPR:
11771 case ROUND_DIV_EXPR:
11772 case EXACT_DIV_EXPR:
11776 case TRUNC_MOD_EXPR:
11777 case FLOOR_MOD_EXPR:
11778 case TRUTH_ANDIF_EXPR:
11779 case TRUTH_ORIF_EXPR:
11780 case TRUTH_AND_EXPR:
11781 case TRUTH_OR_EXPR:
11796 return build_x_binary_op
11798 RECUR (TREE_OPERAND (t, 0)),
11799 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
11801 : TREE_CODE (TREE_OPERAND (t, 0))),
11802 RECUR (TREE_OPERAND (t, 1)),
11803 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
11805 : TREE_CODE (TREE_OPERAND (t, 1))),
11806 /*overloaded_p=*/NULL,
11810 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
11811 /*address_p=*/false);
11813 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11814 args, complain, in_decl);
11815 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
11818 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11819 return tsubst_copy (t, args, complain, in_decl);
11823 op1 = TREE_OPERAND (t, 0);
11826 /* When there are no ARGS, we are trying to evaluate a
11827 non-dependent expression from the parser. Trying to do
11828 the substitutions may not work. */
11830 op1 = TREE_TYPE (op1);
11834 ++cp_unevaluated_operand;
11835 ++c_inhibit_evaluation_warnings;
11836 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
11837 /*function_p=*/false,
11838 /*integral_constant_expression_p=*/false);
11839 --cp_unevaluated_operand;
11840 --c_inhibit_evaluation_warnings;
11843 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
11844 complain & tf_error);
11846 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
11847 complain & tf_error);
11851 tree r = build_x_modify_expr
11852 (RECUR (TREE_OPERAND (t, 0)),
11853 TREE_CODE (TREE_OPERAND (t, 1)),
11854 RECUR (TREE_OPERAND (t, 2)),
11856 /* TREE_NO_WARNING must be set if either the expression was
11857 parenthesized or it uses an operator such as >>= rather
11858 than plain assignment. In the former case, it was already
11859 set and must be copied. In the latter case,
11860 build_x_modify_expr sets it and it must not be reset
11862 if (TREE_NO_WARNING (t))
11863 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11868 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11869 args, complain, in_decl);
11870 /* Remember that there was a reference to this entity. */
11873 return build_x_arrow (op1);
11877 tree placement = RECUR (TREE_OPERAND (t, 0));
11878 tree init = RECUR (TREE_OPERAND (t, 3));
11879 VEC(tree,gc) *placement_vec;
11880 VEC(tree,gc) *init_vec;
11883 if (placement == NULL_TREE)
11884 placement_vec = NULL;
11887 placement_vec = make_tree_vector ();
11888 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
11889 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
11892 /* If there was an initializer in the original tree, but it
11893 instantiated to an empty list, then we should pass a
11894 non-NULL empty vector to tell build_new that it was an
11895 empty initializer() rather than no initializer. This can
11896 only happen when the initializer is a pack expansion whose
11897 parameter packs are of length zero. */
11898 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
11902 init_vec = make_tree_vector ();
11903 if (init == void_zero_node)
11904 gcc_assert (init_vec != NULL);
11907 for (; init != NULL_TREE; init = TREE_CHAIN (init))
11908 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
11912 ret = build_new (&placement_vec,
11913 RECUR (TREE_OPERAND (t, 1)),
11914 RECUR (TREE_OPERAND (t, 2)),
11916 NEW_EXPR_USE_GLOBAL (t),
11919 if (placement_vec != NULL)
11920 release_tree_vector (placement_vec);
11921 if (init_vec != NULL)
11922 release_tree_vector (init_vec);
11928 return delete_sanity
11929 (RECUR (TREE_OPERAND (t, 0)),
11930 RECUR (TREE_OPERAND (t, 1)),
11931 DELETE_EXPR_USE_VEC (t),
11932 DELETE_EXPR_USE_GLOBAL (t));
11934 case COMPOUND_EXPR:
11935 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
11936 RECUR (TREE_OPERAND (t, 1)),
11942 VEC(tree,gc) *call_args;
11943 unsigned int nargs, i;
11948 function = CALL_EXPR_FN (t);
11949 /* When we parsed the expression, we determined whether or
11950 not Koenig lookup should be performed. */
11951 koenig_p = KOENIG_LOOKUP_P (t);
11952 if (TREE_CODE (function) == SCOPE_REF)
11954 qualified_p = true;
11955 function = tsubst_qualified_id (function, args, complain, in_decl,
11957 /*address_p=*/false);
11961 if (TREE_CODE (function) == COMPONENT_REF)
11963 tree op = TREE_OPERAND (function, 1);
11965 qualified_p = (TREE_CODE (op) == SCOPE_REF
11966 || (BASELINK_P (op)
11967 && BASELINK_QUALIFIED_P (op)));
11970 qualified_p = false;
11972 function = tsubst_copy_and_build (function, args, complain,
11975 integral_constant_expression_p);
11977 if (BASELINK_P (function))
11978 qualified_p = true;
11981 nargs = call_expr_nargs (t);
11982 call_args = make_tree_vector ();
11983 for (i = 0; i < nargs; ++i)
11985 tree arg = CALL_EXPR_ARG (t, i);
11987 if (!PACK_EXPANSION_P (arg))
11988 VEC_safe_push (tree, gc, call_args,
11989 RECUR (CALL_EXPR_ARG (t, i)));
11992 /* Expand the pack expansion and push each entry onto
11994 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
11995 if (TREE_CODE (arg) == TREE_VEC)
11997 unsigned int len, j;
11999 len = TREE_VEC_LENGTH (arg);
12000 for (j = 0; j < len; ++j)
12002 tree value = TREE_VEC_ELT (arg, j);
12003 if (value != NULL_TREE)
12004 value = convert_from_reference (value);
12005 VEC_safe_push (tree, gc, call_args, value);
12010 /* A partial substitution. Add one entry. */
12011 VEC_safe_push (tree, gc, call_args, arg);
12016 /* We do not perform argument-dependent lookup if normal
12017 lookup finds a non-function, in accordance with the
12018 expected resolution of DR 218. */
12020 && ((is_overloaded_fn (function)
12021 /* If lookup found a member function, the Koenig lookup is
12022 not appropriate, even if an unqualified-name was used
12023 to denote the function. */
12024 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
12025 || TREE_CODE (function) == IDENTIFIER_NODE)
12026 /* Only do this when substitution turns a dependent call
12027 into a non-dependent call. */
12028 && type_dependent_expression_p_push (t)
12029 && !any_type_dependent_arguments_p (call_args))
12030 function = perform_koenig_lookup (function, call_args);
12032 if (TREE_CODE (function) == IDENTIFIER_NODE)
12034 unqualified_name_lookup_error (function);
12035 release_tree_vector (call_args);
12036 return error_mark_node;
12039 /* Remember that there was a reference to this entity. */
12040 if (DECL_P (function))
12041 mark_used (function);
12043 if (TREE_CODE (function) == OFFSET_REF)
12044 ret = build_offset_ref_call_from_tree (function, &call_args);
12045 else if (TREE_CODE (function) == COMPONENT_REF)
12047 if (!BASELINK_P (TREE_OPERAND (function, 1)))
12048 ret = finish_call_expr (function, &call_args,
12049 /*disallow_virtual=*/false,
12050 /*koenig_p=*/false,
12053 ret = (build_new_method_call
12054 (TREE_OPERAND (function, 0),
12055 TREE_OPERAND (function, 1),
12056 &call_args, NULL_TREE,
12057 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
12062 ret = finish_call_expr (function, &call_args,
12063 /*disallow_virtual=*/qualified_p,
12067 release_tree_vector (call_args);
12073 return build_x_conditional_expr
12074 (RECUR (TREE_OPERAND (t, 0)),
12075 RECUR (TREE_OPERAND (t, 1)),
12076 RECUR (TREE_OPERAND (t, 2)),
12079 case PSEUDO_DTOR_EXPR:
12080 return finish_pseudo_destructor_expr
12081 (RECUR (TREE_OPERAND (t, 0)),
12082 RECUR (TREE_OPERAND (t, 1)),
12083 RECUR (TREE_OPERAND (t, 2)));
12087 tree purpose, value, chain;
12089 if (t == void_list_node)
12092 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
12093 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
12095 /* We have pack expansions, so expand those and
12096 create a new list out of it. */
12097 tree purposevec = NULL_TREE;
12098 tree valuevec = NULL_TREE;
12102 /* Expand the argument expressions. */
12103 if (TREE_PURPOSE (t))
12104 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
12105 complain, in_decl);
12106 if (TREE_VALUE (t))
12107 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
12108 complain, in_decl);
12110 /* Build the rest of the list. */
12111 chain = TREE_CHAIN (t);
12112 if (chain && chain != void_type_node)
12113 chain = RECUR (chain);
12115 /* Determine the number of arguments. */
12116 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
12118 len = TREE_VEC_LENGTH (purposevec);
12119 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
12121 else if (TREE_CODE (valuevec) == TREE_VEC)
12122 len = TREE_VEC_LENGTH (valuevec);
12125 /* Since we only performed a partial substitution into
12126 the argument pack, we only return a single list
12128 if (purposevec == TREE_PURPOSE (t)
12129 && valuevec == TREE_VALUE (t)
12130 && chain == TREE_CHAIN (t))
12133 return tree_cons (purposevec, valuevec, chain);
12136 /* Convert the argument vectors into a TREE_LIST */
12140 /* Grab the Ith values. */
12142 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
12145 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
12148 /* Build the list (backwards). */
12149 chain = tree_cons (purpose, value, chain);
12155 purpose = TREE_PURPOSE (t);
12157 purpose = RECUR (purpose);
12158 value = TREE_VALUE (t);
12160 value = RECUR (value);
12161 chain = TREE_CHAIN (t);
12162 if (chain && chain != void_type_node)
12163 chain = RECUR (chain);
12164 if (purpose == TREE_PURPOSE (t)
12165 && value == TREE_VALUE (t)
12166 && chain == TREE_CHAIN (t))
12168 return tree_cons (purpose, value, chain);
12171 case COMPONENT_REF:
12177 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12178 args, complain, in_decl);
12179 /* Remember that there was a reference to this entity. */
12180 if (DECL_P (object))
12181 mark_used (object);
12182 object_type = TREE_TYPE (object);
12184 member = TREE_OPERAND (t, 1);
12185 if (BASELINK_P (member))
12186 member = tsubst_baselink (member,
12187 non_reference (TREE_TYPE (object)),
12188 args, complain, in_decl);
12190 member = tsubst_copy (member, args, complain, in_decl);
12191 if (member == error_mark_node)
12192 return error_mark_node;
12194 if (object_type && !CLASS_TYPE_P (object_type))
12196 if (SCALAR_TYPE_P (object_type))
12198 tree s = NULL_TREE;
12199 tree dtor = member;
12201 if (TREE_CODE (dtor) == SCOPE_REF)
12203 s = TREE_OPERAND (dtor, 0);
12204 dtor = TREE_OPERAND (dtor, 1);
12206 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
12208 dtor = TREE_OPERAND (dtor, 0);
12210 return finish_pseudo_destructor_expr (object, s, dtor);
12214 else if (TREE_CODE (member) == SCOPE_REF
12215 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
12220 /* Lookup the template functions now that we know what the
12222 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
12223 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
12224 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
12225 /*is_type_p=*/false,
12226 /*complain=*/false);
12227 if (BASELINK_P (member))
12229 BASELINK_FUNCTIONS (member)
12230 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
12232 member = (adjust_result_of_qualified_name_lookup
12233 (member, BINFO_TYPE (BASELINK_BINFO (member)),
12238 qualified_name_lookup_error (object_type, tmpl, member,
12240 return error_mark_node;
12243 else if (TREE_CODE (member) == SCOPE_REF
12244 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
12245 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
12247 if (complain & tf_error)
12249 if (TYPE_P (TREE_OPERAND (member, 0)))
12250 error ("%qT is not a class or namespace",
12251 TREE_OPERAND (member, 0));
12253 error ("%qD is not a class or namespace",
12254 TREE_OPERAND (member, 0));
12256 return error_mark_node;
12258 else if (TREE_CODE (member) == FIELD_DECL)
12259 return finish_non_static_data_member (member, object, NULL_TREE);
12261 return finish_class_member_access_expr (object, member,
12262 /*template_p=*/false,
12268 (RECUR (TREE_OPERAND (t, 0)));
12272 VEC(constructor_elt,gc) *n;
12273 constructor_elt *ce;
12274 unsigned HOST_WIDE_INT idx;
12275 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12276 bool process_index_p;
12278 bool need_copy_p = false;
12281 if (type == error_mark_node)
12282 return error_mark_node;
12284 /* digest_init will do the wrong thing if we let it. */
12285 if (type && TYPE_PTRMEMFUNC_P (type))
12288 /* We do not want to process the index of aggregate
12289 initializers as they are identifier nodes which will be
12290 looked up by digest_init. */
12291 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
12293 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
12294 newlen = VEC_length (constructor_elt, n);
12295 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
12297 if (ce->index && process_index_p)
12298 ce->index = RECUR (ce->index);
12300 if (PACK_EXPANSION_P (ce->value))
12302 /* Substitute into the pack expansion. */
12303 ce->value = tsubst_pack_expansion (ce->value, args, complain,
12306 if (ce->value == error_mark_node)
12308 else if (TREE_VEC_LENGTH (ce->value) == 1)
12309 /* Just move the argument into place. */
12310 ce->value = TREE_VEC_ELT (ce->value, 0);
12313 /* Update the length of the final CONSTRUCTOR
12314 arguments vector, and note that we will need to
12316 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
12317 need_copy_p = true;
12321 ce->value = RECUR (ce->value);
12326 VEC(constructor_elt,gc) *old_n = n;
12328 n = VEC_alloc (constructor_elt, gc, newlen);
12329 for (idx = 0; VEC_iterate (constructor_elt, old_n, idx, ce);
12332 if (TREE_CODE (ce->value) == TREE_VEC)
12334 int i, len = TREE_VEC_LENGTH (ce->value);
12335 for (i = 0; i < len; ++i)
12336 CONSTRUCTOR_APPEND_ELT (n, 0,
12337 TREE_VEC_ELT (ce->value, i));
12340 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
12344 r = build_constructor (init_list_type_node, n);
12345 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
12347 if (TREE_HAS_CONSTRUCTOR (t))
12348 return finish_compound_literal (type, r);
12355 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
12356 if (TYPE_P (operand_0))
12357 return get_typeid (operand_0);
12358 return build_typeid (operand_0);
12368 tree r = tsubst_copy (t, args, complain, in_decl);
12370 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
12371 /* If the original type was a reference, we'll be wrapped in
12372 the appropriate INDIRECT_REF. */
12373 r = convert_from_reference (r);
12378 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
12379 tsubst_copy (TREE_TYPE (t), args, complain,
12382 case OFFSETOF_EXPR:
12383 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
12387 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
12388 complain, in_decl);
12390 tree type2 = TRAIT_EXPR_TYPE2 (t);
12392 type2 = tsubst_copy (type2, args, complain, in_decl);
12394 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
12399 tree old_stmt_expr = cur_stmt_expr;
12400 tree stmt_expr = begin_stmt_expr ();
12402 cur_stmt_expr = stmt_expr;
12403 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
12404 integral_constant_expression_p);
12405 stmt_expr = finish_stmt_expr (stmt_expr, false);
12406 cur_stmt_expr = old_stmt_expr;
12412 t = tsubst_copy (t, args, complain, in_decl);
12413 /* As in finish_id_expression, we resolve enumeration constants
12414 to their underlying values. */
12415 if (TREE_CODE (t) == CONST_DECL)
12417 used_types_insert (TREE_TYPE (t));
12418 return DECL_INITIAL (t);
12424 tree r = build_lambda_expr ();
12426 tree type = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12427 TREE_TYPE (r) = type;
12428 CLASSTYPE_LAMBDA_EXPR (type) = r;
12430 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
12431 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
12432 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
12433 LAMBDA_EXPR_DISCRIMINATOR (r)
12434 = (LAMBDA_EXPR_DISCRIMINATOR (t));
12435 LAMBDA_EXPR_CAPTURE_LIST (r)
12436 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
12437 LAMBDA_EXPR_THIS_CAPTURE (r)
12438 = RECUR (LAMBDA_EXPR_THIS_CAPTURE (t));
12439 LAMBDA_EXPR_EXTRA_SCOPE (r)
12440 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
12442 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
12443 determine_visibility (TYPE_NAME (type));
12444 /* Now that we know visibility, instantiate the type so we have a
12445 declaration of the op() for later calls to lambda_function. */
12446 complete_type (type);
12448 type = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
12450 apply_lambda_return_type (r, type);
12452 return build_lambda_object (r);
12456 /* Handle Objective-C++ constructs, if appropriate. */
12459 = objcp_tsubst_copy_and_build (t, args, complain,
12460 in_decl, /*function_p=*/false);
12464 return tsubst_copy (t, args, complain, in_decl);
12470 /* Verify that the instantiated ARGS are valid. For type arguments,
12471 make sure that the type is not variably modified. For non-type arguments,
12472 make sure they are constants if they are integral or enumerations.
12473 Emit an error under control of COMPLAIN, and return TRUE on error. */
12476 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
12478 if (ARGUMENT_PACK_P (t))
12480 tree vec = ARGUMENT_PACK_ARGS (t);
12481 int len = TREE_VEC_LENGTH (vec);
12482 bool result = false;
12485 for (i = 0; i < len; ++i)
12486 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
12490 else if (TYPE_P (t))
12492 if (variably_modified_type_p (t, NULL_TREE))
12494 if (complain & tf_error)
12495 error ("%qT is a variably modified type", t);
12499 /* A non-type argument of integral or enumerated type must be a
12501 else if (TREE_TYPE (t)
12502 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
12503 && !TREE_CONSTANT (t))
12505 if (complain & tf_error)
12506 error ("integral expression %qE is not constant", t);
12513 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
12515 int ix, len = DECL_NTPARMS (tmpl);
12516 bool result = false;
12518 for (ix = 0; ix != len; ix++)
12520 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
12523 if (result && (complain & tf_error))
12524 error (" trying to instantiate %qD", tmpl);
12528 /* Instantiate the indicated variable or function template TMPL with
12529 the template arguments in TARG_PTR. */
12532 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
12534 tree targ_ptr = orig_args;
12538 HOST_WIDE_INT saved_processing_template_decl;
12540 if (tmpl == error_mark_node)
12541 return error_mark_node;
12543 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
12545 /* If this function is a clone, handle it specially. */
12546 if (DECL_CLONED_FUNCTION_P (tmpl))
12551 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
12552 DECL_CLONED_FUNCTION. */
12553 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
12554 targ_ptr, complain);
12555 if (spec == error_mark_node)
12556 return error_mark_node;
12558 /* Look for the clone. */
12559 FOR_EACH_CLONE (clone, spec)
12560 if (DECL_NAME (clone) == DECL_NAME (tmpl))
12562 /* We should always have found the clone by now. */
12563 gcc_unreachable ();
12567 /* Check to see if we already have this specialization. */
12568 gen_tmpl = most_general_template (tmpl);
12569 if (tmpl != gen_tmpl)
12570 /* The TMPL is a partial instantiation. To get a full set of
12571 arguments we must add the arguments used to perform the
12572 partial instantiation. */
12573 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
12576 /* It would be nice to avoid hashing here and then again in tsubst_decl,
12577 but it doesn't seem to be on the hot path. */
12578 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
12580 gcc_assert (tmpl == gen_tmpl
12581 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
12583 || fndecl == NULL_TREE);
12585 if (spec != NULL_TREE)
12588 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
12590 return error_mark_node;
12592 /* We are building a FUNCTION_DECL, during which the access of its
12593 parameters and return types have to be checked. However this
12594 FUNCTION_DECL which is the desired context for access checking
12595 is not built yet. We solve this chicken-and-egg problem by
12596 deferring all checks until we have the FUNCTION_DECL. */
12597 push_deferring_access_checks (dk_deferred);
12599 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
12600 (because, for example, we have encountered a non-dependent
12601 function call in the body of a template function and must now
12602 determine which of several overloaded functions will be called),
12603 within the instantiation itself we are not processing a
12605 saved_processing_template_decl = processing_template_decl;
12606 processing_template_decl = 0;
12607 /* Substitute template parameters to obtain the specialization. */
12608 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
12609 targ_ptr, complain, gen_tmpl);
12610 processing_template_decl = saved_processing_template_decl;
12611 if (fndecl == error_mark_node)
12612 return error_mark_node;
12614 /* Now we know the specialization, compute access previously
12616 push_access_scope (fndecl);
12618 /* Some typedefs referenced from within the template code need to be access
12619 checked at template instantiation time, i.e now. These types were
12620 added to the template at parsing time. Let's get those and perfom
12621 the acces checks then. */
12622 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
12623 perform_deferred_access_checks ();
12624 pop_access_scope (fndecl);
12625 pop_deferring_access_checks ();
12627 /* The DECL_TI_TEMPLATE should always be the immediate parent
12628 template, not the most general template. */
12629 DECL_TI_TEMPLATE (fndecl) = tmpl;
12631 /* If we've just instantiated the main entry point for a function,
12632 instantiate all the alternate entry points as well. We do this
12633 by cloning the instantiation of the main entry point, not by
12634 instantiating the template clones. */
12635 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
12636 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
12641 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
12642 NARGS elements of the arguments that are being used when calling
12643 it. TARGS is a vector into which the deduced template arguments
12646 Return zero for success, 2 for an incomplete match that doesn't resolve
12647 all the types, and 1 for complete failure. An error message will be
12648 printed only for an incomplete match.
12650 If FN is a conversion operator, or we are trying to produce a specific
12651 specialization, RETURN_TYPE is the return type desired.
12653 The EXPLICIT_TARGS are explicit template arguments provided via a
12656 The parameter STRICT is one of:
12659 We are deducing arguments for a function call, as in
12660 [temp.deduct.call].
12663 We are deducing arguments for a conversion function, as in
12664 [temp.deduct.conv].
12667 We are deducing arguments when doing an explicit instantiation
12668 as in [temp.explicit], when determining an explicit specialization
12669 as in [temp.expl.spec], or when taking the address of a function
12670 template, as in [temp.deduct.funcaddr]. */
12673 fn_type_unification (tree fn,
12674 tree explicit_targs,
12677 unsigned int nargs,
12679 unification_kind_t strict,
12685 bool incomplete_argument_packs_p = false;
12687 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
12689 fntype = TREE_TYPE (fn);
12690 if (explicit_targs)
12694 The specified template arguments must match the template
12695 parameters in kind (i.e., type, nontype, template), and there
12696 must not be more arguments than there are parameters;
12697 otherwise type deduction fails.
12699 Nontype arguments must match the types of the corresponding
12700 nontype template parameters, or must be convertible to the
12701 types of the corresponding nontype parameters as specified in
12702 _temp.arg.nontype_, otherwise type deduction fails.
12704 All references in the function type of the function template
12705 to the corresponding template parameters are replaced by the
12706 specified template argument values. If a substitution in a
12707 template parameter or in the function type of the function
12708 template results in an invalid type, type deduction fails. */
12709 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
12710 int i, len = TREE_VEC_LENGTH (tparms);
12711 tree converted_args;
12712 bool incomplete = false;
12714 if (explicit_targs == error_mark_node)
12718 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
12719 /*require_all_args=*/false,
12720 /*use_default_args=*/false));
12721 if (converted_args == error_mark_node)
12724 /* Substitute the explicit args into the function type. This is
12725 necessary so that, for instance, explicitly declared function
12726 arguments can match null pointed constants. If we were given
12727 an incomplete set of explicit args, we must not do semantic
12728 processing during substitution as we could create partial
12730 for (i = 0; i < len; i++)
12732 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
12733 bool parameter_pack = false;
12735 /* Dig out the actual parm. */
12736 if (TREE_CODE (parm) == TYPE_DECL
12737 || TREE_CODE (parm) == TEMPLATE_DECL)
12739 parm = TREE_TYPE (parm);
12740 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
12742 else if (TREE_CODE (parm) == PARM_DECL)
12744 parm = DECL_INITIAL (parm);
12745 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
12748 if (parameter_pack)
12752 template_parm_level_and_index (parm, &level, &idx);
12754 /* Mark the argument pack as "incomplete". We could
12755 still deduce more arguments during unification. */
12756 targ = TMPL_ARG (converted_args, level, idx);
12759 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
12760 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
12761 = ARGUMENT_PACK_ARGS (targ);
12764 /* We have some incomplete argument packs. */
12765 incomplete_argument_packs_p = true;
12769 if (incomplete_argument_packs_p)
12770 /* Any substitution is guaranteed to be incomplete if there
12771 are incomplete argument packs, because we can still deduce
12775 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
12777 processing_template_decl += incomplete;
12778 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
12779 processing_template_decl -= incomplete;
12781 if (fntype == error_mark_node)
12784 /* Place the explicitly specified arguments in TARGS. */
12785 for (i = NUM_TMPL_ARGS (converted_args); i--;)
12786 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
12789 /* Never do unification on the 'this' parameter. */
12790 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
12796 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
12797 new_args = XALLOCAVEC (tree, nargs + 1);
12798 new_args[0] = return_type;
12799 memcpy (new_args + 1, args, nargs * sizeof (tree));
12804 /* We allow incomplete unification without an error message here
12805 because the standard doesn't seem to explicitly prohibit it. Our
12806 callers must be ready to deal with unification failures in any
12808 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
12809 targs, parms, args, nargs, /*subr=*/0,
12812 if (result == 0 && incomplete_argument_packs_p)
12814 int i, len = NUM_TMPL_ARGS (targs);
12816 /* Clear the "incomplete" flags on all argument packs. */
12817 for (i = 0; i < len; i++)
12819 tree arg = TREE_VEC_ELT (targs, i);
12820 if (ARGUMENT_PACK_P (arg))
12822 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
12823 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
12828 /* Now that we have bindings for all of the template arguments,
12829 ensure that the arguments deduced for the template template
12830 parameters have compatible template parameter lists. We cannot
12831 check this property before we have deduced all template
12832 arguments, because the template parameter types of a template
12833 template parameter might depend on prior template parameters
12834 deduced after the template template parameter. The following
12835 ill-formed example illustrates this issue:
12837 template<typename T, template<T> class C> void f(C<5>, T);
12839 template<int N> struct X {};
12842 f(X<5>(), 5l); // error: template argument deduction fails
12845 The template parameter list of 'C' depends on the template type
12846 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
12847 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
12848 time that we deduce 'C'. */
12850 && !template_template_parm_bindings_ok_p
12851 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
12855 /* All is well so far. Now, check:
12859 When all template arguments have been deduced, all uses of
12860 template parameters in nondeduced contexts are replaced with
12861 the corresponding deduced argument values. If the
12862 substitution results in an invalid type, as described above,
12863 type deduction fails. */
12865 tree substed = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE);
12866 if (substed == error_mark_node)
12869 /* If we're looking for an exact match, check that what we got
12870 is indeed an exact match. It might not be if some template
12871 parameters are used in non-deduced contexts. */
12872 if (strict == DEDUCE_EXACT)
12877 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
12879 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
12880 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
12881 if (!same_type_p (args[i], TREE_VALUE (sarg)))
12889 /* Adjust types before performing type deduction, as described in
12890 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
12891 sections are symmetric. PARM is the type of a function parameter
12892 or the return type of the conversion function. ARG is the type of
12893 the argument passed to the call, or the type of the value
12894 initialized with the result of the conversion function.
12895 ARG_EXPR is the original argument expression, which may be null. */
12898 maybe_adjust_types_for_deduction (unification_kind_t strict,
12912 /* Swap PARM and ARG throughout the remainder of this
12913 function; the handling is precisely symmetric since PARM
12914 will initialize ARG rather than vice versa. */
12922 /* Core issue #873: Do the DR606 thing (see below) for these cases,
12923 too, but here handle it by stripping the reference from PARM
12924 rather than by adding it to ARG. */
12925 if (TREE_CODE (*parm) == REFERENCE_TYPE
12926 && TYPE_REF_IS_RVALUE (*parm)
12927 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
12928 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
12929 && TREE_CODE (*arg) == REFERENCE_TYPE
12930 && !TYPE_REF_IS_RVALUE (*arg))
12931 *parm = TREE_TYPE (*parm);
12932 /* Nothing else to do in this case. */
12936 gcc_unreachable ();
12939 if (TREE_CODE (*parm) != REFERENCE_TYPE)
12941 /* [temp.deduct.call]
12943 If P is not a reference type:
12945 --If A is an array type, the pointer type produced by the
12946 array-to-pointer standard conversion (_conv.array_) is
12947 used in place of A for type deduction; otherwise,
12949 --If A is a function type, the pointer type produced by
12950 the function-to-pointer standard conversion
12951 (_conv.func_) is used in place of A for type deduction;
12954 --If A is a cv-qualified type, the top level
12955 cv-qualifiers of A's type are ignored for type
12957 if (TREE_CODE (*arg) == ARRAY_TYPE)
12958 *arg = build_pointer_type (TREE_TYPE (*arg));
12959 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
12960 *arg = build_pointer_type (*arg);
12962 *arg = TYPE_MAIN_VARIANT (*arg);
12965 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
12966 of the form T&&, where T is a template parameter, and the argument
12967 is an lvalue, T is deduced as A& */
12968 if (TREE_CODE (*parm) == REFERENCE_TYPE
12969 && TYPE_REF_IS_RVALUE (*parm)
12970 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
12971 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
12972 && arg_expr && real_lvalue_p (arg_expr))
12973 *arg = build_reference_type (*arg);
12975 /* [temp.deduct.call]
12977 If P is a cv-qualified type, the top level cv-qualifiers
12978 of P's type are ignored for type deduction. If P is a
12979 reference type, the type referred to by P is used for
12981 *parm = TYPE_MAIN_VARIANT (*parm);
12982 if (TREE_CODE (*parm) == REFERENCE_TYPE)
12984 *parm = TREE_TYPE (*parm);
12985 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
12988 /* DR 322. For conversion deduction, remove a reference type on parm
12989 too (which has been swapped into ARG). */
12990 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
12991 *arg = TREE_TYPE (*arg);
12996 /* Most parms like fn_type_unification.
12998 If SUBR is 1, we're being called recursively (to unify the
12999 arguments of a function or method parameter of a function
13003 type_unification_real (tree tparms,
13007 unsigned int xnargs,
13009 unification_kind_t strict,
13012 tree parm, arg, arg_expr;
13014 int ntparms = TREE_VEC_LENGTH (tparms);
13016 int saw_undeduced = 0;
13019 unsigned int nargs;
13022 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
13023 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
13024 gcc_assert (ntparms > 0);
13029 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
13030 | UNIFY_ALLOW_DERIVED);
13034 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
13038 sub_strict = UNIFY_ALLOW_NONE;
13042 gcc_unreachable ();
13051 while (parms && parms != void_list_node
13054 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13057 parm = TREE_VALUE (parms);
13058 parms = TREE_CHAIN (parms);
13063 if (arg == error_mark_node)
13065 if (arg == unknown_type_node)
13066 /* We can't deduce anything from this, but we might get all the
13067 template args from other function args. */
13070 /* Conversions will be performed on a function argument that
13071 corresponds with a function parameter that contains only
13072 non-deducible template parameters and explicitly specified
13073 template parameters. */
13074 if (!uses_template_parms (parm))
13079 type = TREE_TYPE (arg);
13083 if (same_type_p (parm, type))
13085 if (strict != DEDUCE_EXACT
13086 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
13095 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
13096 if (type_unknown_p (arg))
13098 /* [temp.deduct.type]
13100 A template-argument can be deduced from a pointer to
13101 function or pointer to member function argument if
13102 the set of overloaded functions does not contain
13103 function templates and at most one of a set of
13104 overloaded functions provides a unique match. */
13105 if (resolve_overloaded_unification
13106 (tparms, targs, parm, arg, strict, sub_strict))
13112 arg = unlowered_expr_type (arg);
13113 if (arg == error_mark_node)
13118 int arg_strict = sub_strict;
13121 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
13124 if (arg == init_list_type_node && arg_expr)
13126 if (unify (tparms, targs, parm, arg, arg_strict))
13133 && parms != void_list_node
13134 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13136 /* Unify the remaining arguments with the pack expansion type. */
13138 tree parmvec = make_tree_vec (1);
13140 /* Allocate a TREE_VEC and copy in all of the arguments */
13141 argvec = make_tree_vec (nargs - ia);
13142 for (i = 0; ia < nargs; ++ia, ++i)
13143 TREE_VEC_ELT (argvec, i) = args[ia];
13145 /* Copy the parameter into parmvec. */
13146 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
13147 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
13148 /*call_args_p=*/true, /*subr=*/subr))
13151 /* Advance to the end of the list of parameters. */
13152 parms = TREE_CHAIN (parms);
13155 /* Fail if we've reached the end of the parm list, and more args
13156 are present, and the parm list isn't variadic. */
13157 if (ia < nargs && parms == void_list_node)
13159 /* Fail if parms are left and they don't have default values. */
13160 if (parms && parms != void_list_node
13161 && TREE_PURPOSE (parms) == NULL_TREE)
13165 for (i = 0; i < ntparms; i++)
13166 if (!TREE_VEC_ELT (targs, i))
13170 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
13173 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13175 /* If this is an undeduced nontype parameter that depends on
13176 a type parameter, try another pass; its type may have been
13177 deduced from a later argument than the one from which
13178 this parameter can be deduced. */
13179 if (TREE_CODE (tparm) == PARM_DECL
13180 && uses_template_parms (TREE_TYPE (tparm))
13181 && !saw_undeduced++)
13184 /* Core issue #226 (C++0x) [temp.deduct]:
13186 If a template argument has not been deduced, its
13187 default template argument, if any, is used.
13189 When we are in C++98 mode, TREE_PURPOSE will either
13190 be NULL_TREE or ERROR_MARK_NODE, so we do not need
13191 to explicitly check cxx_dialect here. */
13192 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
13194 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13195 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
13196 arg = tsubst_template_arg (arg, targs, tf_none, NULL_TREE);
13197 arg = convert_template_argument (parm, arg, targs, tf_none,
13199 if (arg == error_mark_node)
13203 TREE_VEC_ELT (targs, i) = arg;
13208 /* If the type parameter is a parameter pack, then it will
13209 be deduced to an empty parameter pack. */
13210 if (template_parameter_pack_p (tparm))
13214 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
13216 arg = make_node (NONTYPE_ARGUMENT_PACK);
13217 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
13218 TREE_CONSTANT (arg) = 1;
13221 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
13223 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
13225 TREE_VEC_ELT (targs, i) = arg;
13235 /* Subroutine of type_unification_real. Args are like the variables
13236 at the call site. ARG is an overloaded function (or template-id);
13237 we try deducing template args from each of the overloads, and if
13238 only one succeeds, we go with that. Modifies TARGS and returns
13239 true on success. */
13242 resolve_overloaded_unification (tree tparms,
13246 unification_kind_t strict,
13249 tree tempargs = copy_node (targs);
13251 tree goodfn = NULL_TREE;
13254 if (TREE_CODE (arg) == ADDR_EXPR)
13256 arg = TREE_OPERAND (arg, 0);
13262 if (TREE_CODE (arg) == COMPONENT_REF)
13263 /* Handle `&x' where `x' is some static or non-static member
13265 arg = TREE_OPERAND (arg, 1);
13267 if (TREE_CODE (arg) == OFFSET_REF)
13268 arg = TREE_OPERAND (arg, 1);
13270 /* Strip baselink information. */
13271 if (BASELINK_P (arg))
13272 arg = BASELINK_FUNCTIONS (arg);
13274 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
13276 /* If we got some explicit template args, we need to plug them into
13277 the affected templates before we try to unify, in case the
13278 explicit args will completely resolve the templates in question. */
13280 tree expl_subargs = TREE_OPERAND (arg, 1);
13281 arg = TREE_OPERAND (arg, 0);
13283 for (; arg; arg = OVL_NEXT (arg))
13285 tree fn = OVL_CURRENT (arg);
13286 tree subargs, elem;
13288 if (TREE_CODE (fn) != TEMPLATE_DECL)
13291 ++processing_template_decl;
13292 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13293 expl_subargs, /*check_ret=*/false);
13296 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
13297 if (try_one_overload (tparms, targs, tempargs, parm,
13298 elem, strict, sub_strict, addr_p)
13299 && (!goodfn || !decls_match (goodfn, elem)))
13305 --processing_template_decl;
13308 else if (TREE_CODE (arg) != OVERLOAD
13309 && TREE_CODE (arg) != FUNCTION_DECL)
13310 /* If ARG is, for example, "(0, &f)" then its type will be unknown
13311 -- but the deduction does not succeed because the expression is
13312 not just the function on its own. */
13315 for (; arg; arg = OVL_NEXT (arg))
13316 if (try_one_overload (tparms, targs, tempargs, parm,
13317 TREE_TYPE (OVL_CURRENT (arg)),
13318 strict, sub_strict, addr_p)
13319 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
13321 goodfn = OVL_CURRENT (arg);
13325 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13326 to function or pointer to member function argument if the set of
13327 overloaded functions does not contain function templates and at most
13328 one of a set of overloaded functions provides a unique match.
13330 So if we found multiple possibilities, we return success but don't
13331 deduce anything. */
13335 int i = TREE_VEC_LENGTH (targs);
13337 if (TREE_VEC_ELT (tempargs, i))
13338 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
13346 /* Core DR 115: In contexts where deduction is done and fails, or in
13347 contexts where deduction is not done, if a template argument list is
13348 specified and it, along with any default template arguments, identifies
13349 a single function template specialization, then the template-id is an
13350 lvalue for the function template specialization. */
13353 resolve_nondeduced_context (tree orig_expr)
13355 tree expr, offset, baselink;
13358 if (!type_unknown_p (orig_expr))
13363 offset = NULL_TREE;
13364 baselink = NULL_TREE;
13366 if (TREE_CODE (expr) == ADDR_EXPR)
13368 expr = TREE_OPERAND (expr, 0);
13371 if (TREE_CODE (expr) == OFFSET_REF)
13374 expr = TREE_OPERAND (expr, 1);
13376 if (TREE_CODE (expr) == BASELINK)
13379 expr = BASELINK_FUNCTIONS (expr);
13382 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
13385 tree goodfn = NULL_TREE;
13387 /* If we got some explicit template args, we need to plug them into
13388 the affected templates before we try to unify, in case the
13389 explicit args will completely resolve the templates in question. */
13391 tree expl_subargs = TREE_OPERAND (expr, 1);
13392 tree arg = TREE_OPERAND (expr, 0);
13393 tree badfn = NULL_TREE;
13394 tree badargs = NULL_TREE;
13396 for (; arg; arg = OVL_NEXT (arg))
13398 tree fn = OVL_CURRENT (arg);
13399 tree subargs, elem;
13401 if (TREE_CODE (fn) != TEMPLATE_DECL)
13404 ++processing_template_decl;
13405 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13406 expl_subargs, /*check_ret=*/false);
13407 if (subargs && !any_dependent_template_arguments_p (subargs))
13409 elem = instantiate_template (fn, subargs, tf_none);
13410 if (elem == error_mark_node)
13415 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
13421 --processing_template_decl;
13427 expr = build_baselink (BASELINK_BINFO (baselink),
13428 BASELINK_ACCESS_BINFO (baselink),
13429 expr, BASELINK_OPTYPE (baselink));
13431 expr = build2 (OFFSET_REF, TREE_TYPE (expr),
13432 TREE_OPERAND (offset, 0), expr);
13434 expr = build_address (expr);
13437 else if (good == 0 && badargs)
13438 /* There were no good options and at least one bad one, so let the
13439 user know what the problem is. */
13440 instantiate_template (badfn, badargs, tf_warning_or_error);
13445 /* Subroutine of resolve_overloaded_unification; does deduction for a single
13446 overload. Fills TARGS with any deduced arguments, or error_mark_node if
13447 different overloads deduce different arguments for a given parm.
13448 ADDR_P is true if the expression for which deduction is being
13449 performed was of the form "& fn" rather than simply "fn".
13451 Returns 1 on success. */
13454 try_one_overload (tree tparms,
13459 unification_kind_t strict,
13467 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13468 to function or pointer to member function argument if the set of
13469 overloaded functions does not contain function templates and at most
13470 one of a set of overloaded functions provides a unique match.
13472 So if this is a template, just return success. */
13474 if (uses_template_parms (arg))
13477 if (TREE_CODE (arg) == METHOD_TYPE)
13478 arg = build_ptrmemfunc_type (build_pointer_type (arg));
13480 arg = build_pointer_type (arg);
13482 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
13484 /* We don't copy orig_targs for this because if we have already deduced
13485 some template args from previous args, unify would complain when we
13486 try to deduce a template parameter for the same argument, even though
13487 there isn't really a conflict. */
13488 nargs = TREE_VEC_LENGTH (targs);
13489 tempargs = make_tree_vec (nargs);
13491 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
13494 /* First make sure we didn't deduce anything that conflicts with
13495 explicitly specified args. */
13496 for (i = nargs; i--; )
13498 tree elt = TREE_VEC_ELT (tempargs, i);
13499 tree oldelt = TREE_VEC_ELT (orig_targs, i);
13503 else if (uses_template_parms (elt))
13504 /* Since we're unifying against ourselves, we will fill in
13505 template args used in the function parm list with our own
13506 template parms. Discard them. */
13507 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
13508 else if (oldelt && !template_args_equal (oldelt, elt))
13512 for (i = nargs; i--; )
13514 tree elt = TREE_VEC_ELT (tempargs, i);
13517 TREE_VEC_ELT (targs, i) = elt;
13523 /* PARM is a template class (perhaps with unbound template
13524 parameters). ARG is a fully instantiated type. If ARG can be
13525 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
13526 TARGS are as for unify. */
13529 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
13531 tree copy_of_targs;
13533 if (!CLASSTYPE_TEMPLATE_INFO (arg)
13534 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
13535 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
13538 /* We need to make a new template argument vector for the call to
13539 unify. If we used TARGS, we'd clutter it up with the result of
13540 the attempted unification, even if this class didn't work out.
13541 We also don't want to commit ourselves to all the unifications
13542 we've already done, since unification is supposed to be done on
13543 an argument-by-argument basis. In other words, consider the
13544 following pathological case:
13546 template <int I, int J, int K>
13549 template <int I, int J>
13550 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
13552 template <int I, int J, int K>
13553 void f(S<I, J, K>, S<I, I, I>);
13562 Now, by the time we consider the unification involving `s2', we
13563 already know that we must have `f<0, 0, 0>'. But, even though
13564 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
13565 because there are two ways to unify base classes of S<0, 1, 2>
13566 with S<I, I, I>. If we kept the already deduced knowledge, we
13567 would reject the possibility I=1. */
13568 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
13570 /* If unification failed, we're done. */
13571 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
13572 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
13578 /* Given a template type PARM and a class type ARG, find the unique
13579 base type in ARG that is an instance of PARM. We do not examine
13580 ARG itself; only its base-classes. If there is not exactly one
13581 appropriate base class, return NULL_TREE. PARM may be the type of
13582 a partial specialization, as well as a plain template type. Used
13586 get_template_base (tree tparms, tree targs, tree parm, tree arg)
13588 tree rval = NULL_TREE;
13591 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
13593 binfo = TYPE_BINFO (complete_type (arg));
13595 /* The type could not be completed. */
13598 /* Walk in inheritance graph order. The search order is not
13599 important, and this avoids multiple walks of virtual bases. */
13600 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
13602 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
13606 /* If there is more than one satisfactory baseclass, then:
13610 If they yield more than one possible deduced A, the type
13614 if (rval && !same_type_p (r, rval))
13624 /* Returns the level of DECL, which declares a template parameter. */
13627 template_decl_level (tree decl)
13629 switch (TREE_CODE (decl))
13632 case TEMPLATE_DECL:
13633 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
13636 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
13639 gcc_unreachable ();
13644 /* Decide whether ARG can be unified with PARM, considering only the
13645 cv-qualifiers of each type, given STRICT as documented for unify.
13646 Returns nonzero iff the unification is OK on that basis. */
13649 check_cv_quals_for_unify (int strict, tree arg, tree parm)
13651 int arg_quals = cp_type_quals (arg);
13652 int parm_quals = cp_type_quals (parm);
13654 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13655 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
13657 /* Although a CVR qualifier is ignored when being applied to a
13658 substituted template parameter ([8.3.2]/1 for example), that
13659 does not apply during deduction [14.8.2.4]/1, (even though
13660 that is not explicitly mentioned, [14.8.2.4]/9 indicates
13661 this). Except when we're allowing additional CV qualifiers
13662 at the outer level [14.8.2.1]/3,1st bullet. */
13663 if ((TREE_CODE (arg) == REFERENCE_TYPE
13664 || TREE_CODE (arg) == FUNCTION_TYPE
13665 || TREE_CODE (arg) == METHOD_TYPE)
13666 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
13669 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
13670 && (parm_quals & TYPE_QUAL_RESTRICT))
13674 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
13675 && (arg_quals & parm_quals) != parm_quals)
13678 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
13679 && (parm_quals & arg_quals) != arg_quals)
13685 /* Determines the LEVEL and INDEX for the template parameter PARM. */
13687 template_parm_level_and_index (tree parm, int* level, int* index)
13689 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13690 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13691 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13693 *index = TEMPLATE_TYPE_IDX (parm);
13694 *level = TEMPLATE_TYPE_LEVEL (parm);
13698 *index = TEMPLATE_PARM_IDX (parm);
13699 *level = TEMPLATE_PARM_LEVEL (parm);
13703 /* Unifies the remaining arguments in PACKED_ARGS with the pack
13704 expansion at the end of PACKED_PARMS. Returns 0 if the type
13705 deduction succeeds, 1 otherwise. STRICT is the same as in
13706 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
13707 call argument list. We'll need to adjust the arguments to make them
13708 types. SUBR tells us if this is from a recursive call to
13709 type_unification_real. */
13711 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
13712 tree packed_args, int strict, bool call_args_p,
13716 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
13717 tree pattern = PACK_EXPANSION_PATTERN (parm);
13718 tree pack, packs = NULL_TREE;
13719 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
13720 int len = TREE_VEC_LENGTH (packed_args);
13722 /* Determine the parameter packs we will be deducing from the
13723 pattern, and record their current deductions. */
13724 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
13725 pack; pack = TREE_CHAIN (pack))
13727 tree parm_pack = TREE_VALUE (pack);
13730 /* Determine the index and level of this parameter pack. */
13731 template_parm_level_and_index (parm_pack, &level, &idx);
13733 /* Keep track of the parameter packs and their corresponding
13735 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
13736 TREE_TYPE (packs) = make_tree_vec (len - start);
13739 /* Loop through all of the arguments that have not yet been
13740 unified and unify each with the pattern. */
13741 for (i = start; i < len; i++)
13743 tree parm = pattern;
13745 /* For each parameter pack, clear out the deduced value so that
13746 we can deduce it again. */
13747 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13750 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13752 TMPL_ARG (targs, level, idx) = NULL_TREE;
13755 /* Unify the pattern with the current argument. */
13757 tree arg = TREE_VEC_ELT (packed_args, i);
13758 tree arg_expr = NULL_TREE;
13759 int arg_strict = strict;
13760 bool skip_arg_p = false;
13766 /* This mirrors what we do in type_unification_real. */
13770 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
13771 | UNIFY_ALLOW_MORE_CV_QUAL
13772 | UNIFY_ALLOW_DERIVED);
13776 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
13780 sub_strict = UNIFY_ALLOW_NONE;
13784 gcc_unreachable ();
13789 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
13790 if (type_unknown_p (arg))
13792 /* [temp.deduct.type] A template-argument can be
13793 deduced from a pointer to function or pointer
13794 to member function argument if the set of
13795 overloaded functions does not contain function
13796 templates and at most one of a set of
13797 overloaded functions provides a unique
13800 if (resolve_overloaded_unification
13801 (tparms, targs, parm, arg,
13802 (unification_kind_t) strict,
13812 arg = unlowered_expr_type (arg);
13813 if (arg == error_mark_node)
13818 arg_strict = sub_strict;
13822 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
13823 &parm, &arg, arg_expr);
13828 if (unify (tparms, targs, parm, arg, arg_strict))
13833 /* For each parameter pack, collect the deduced value. */
13834 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13837 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13839 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
13840 TMPL_ARG (targs, level, idx);
13844 /* Verify that the results of unification with the parameter packs
13845 produce results consistent with what we've seen before, and make
13846 the deduced argument packs available. */
13847 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13849 tree old_pack = TREE_VALUE (pack);
13850 tree new_args = TREE_TYPE (pack);
13851 int i, len = TREE_VEC_LENGTH (new_args);
13852 bool nondeduced_p = false;
13854 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
13855 actually deduce anything. */
13856 for (i = 0; i < len && !nondeduced_p; ++i)
13857 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
13858 nondeduced_p = true;
13862 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
13864 /* Prepend the explicit arguments onto NEW_ARGS. */
13865 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
13866 tree old_args = new_args;
13867 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
13868 int len = explicit_len + TREE_VEC_LENGTH (old_args);
13870 /* Copy the explicit arguments. */
13871 new_args = make_tree_vec (len);
13872 for (i = 0; i < explicit_len; i++)
13873 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
13875 /* Copy the deduced arguments. */
13876 for (; i < len; i++)
13877 TREE_VEC_ELT (new_args, i) =
13878 TREE_VEC_ELT (old_args, i - explicit_len);
13886 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13888 /* Build the deduced *_ARGUMENT_PACK. */
13889 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
13891 result = make_node (NONTYPE_ARGUMENT_PACK);
13892 TREE_TYPE (result) =
13893 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
13894 TREE_CONSTANT (result) = 1;
13897 result = cxx_make_type (TYPE_ARGUMENT_PACK);
13899 SET_ARGUMENT_PACK_ARGS (result, new_args);
13901 /* Note the deduced argument packs for this parameter
13903 TMPL_ARG (targs, level, idx) = result;
13905 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
13906 && (ARGUMENT_PACK_ARGS (old_pack)
13907 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
13909 /* We only had the explicitly-provided arguments before, but
13910 now we have a complete set of arguments. */
13912 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
13913 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13915 /* Keep the original deduced argument pack. */
13916 TMPL_ARG (targs, level, idx) = old_pack;
13918 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
13919 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
13920 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
13922 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
13924 /* Inconsistent unification of this parameter pack. */
13930 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13932 /* Keep the original deduced argument pack. */
13933 TMPL_ARG (targs, level, idx) = old_pack;
13940 /* Deduce the value of template parameters. TPARMS is the (innermost)
13941 set of template parameters to a template. TARGS is the bindings
13942 for those template parameters, as determined thus far; TARGS may
13943 include template arguments for outer levels of template parameters
13944 as well. PARM is a parameter to a template function, or a
13945 subcomponent of that parameter; ARG is the corresponding argument.
13946 This function attempts to match PARM with ARG in a manner
13947 consistent with the existing assignments in TARGS. If more values
13948 are deduced, then TARGS is updated.
13950 Returns 0 if the type deduction succeeds, 1 otherwise. The
13951 parameter STRICT is a bitwise or of the following flags:
13954 Require an exact match between PARM and ARG.
13955 UNIFY_ALLOW_MORE_CV_QUAL:
13956 Allow the deduced ARG to be more cv-qualified (by qualification
13957 conversion) than ARG.
13958 UNIFY_ALLOW_LESS_CV_QUAL:
13959 Allow the deduced ARG to be less cv-qualified than ARG.
13960 UNIFY_ALLOW_DERIVED:
13961 Allow the deduced ARG to be a template base class of ARG,
13962 or a pointer to a template base class of the type pointed to by
13964 UNIFY_ALLOW_INTEGER:
13965 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
13966 case for more information.
13967 UNIFY_ALLOW_OUTER_LEVEL:
13968 This is the outermost level of a deduction. Used to determine validity
13969 of qualification conversions. A valid qualification conversion must
13970 have const qualified pointers leading up to the inner type which
13971 requires additional CV quals, except at the outer level, where const
13972 is not required [conv.qual]. It would be normal to set this flag in
13973 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
13974 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
13975 This is the outermost level of a deduction, and PARM can be more CV
13976 qualified at this point.
13977 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
13978 This is the outermost level of a deduction, and PARM can be less CV
13979 qualified at this point. */
13982 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
13987 int strict_in = strict;
13989 /* I don't think this will do the right thing with respect to types.
13990 But the only case I've seen it in so far has been array bounds, where
13991 signedness is the only information lost, and I think that will be
13993 while (TREE_CODE (parm) == NOP_EXPR)
13994 parm = TREE_OPERAND (parm, 0);
13996 if (arg == error_mark_node)
13998 if (arg == unknown_type_node
13999 || arg == init_list_type_node)
14000 /* We can't deduce anything from this, but we might get all the
14001 template args from other function args. */
14004 /* If PARM uses template parameters, then we can't bail out here,
14005 even if ARG == PARM, since we won't record unifications for the
14006 template parameters. We might need them if we're trying to
14007 figure out which of two things is more specialized. */
14008 if (arg == parm && !uses_template_parms (parm))
14011 /* Handle init lists early, so the rest of the function can assume
14012 we're dealing with a type. */
14013 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
14017 tree orig_parm = parm;
14019 /* Replace T with std::initializer_list<T> for deduction. */
14020 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14021 && flag_deduce_init_list)
14022 parm = listify (parm);
14024 if (!is_std_init_list (parm))
14025 /* We can only deduce from an initializer list argument if the
14026 parameter is std::initializer_list; otherwise this is a
14027 non-deduced context. */
14030 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
14032 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
14034 int elt_strict = strict;
14035 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
14037 tree type = TREE_TYPE (elt);
14038 /* It should only be possible to get here for a call. */
14039 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
14040 elt_strict |= maybe_adjust_types_for_deduction
14041 (DEDUCE_CALL, &elttype, &type, elt);
14045 if (unify (tparms, targs, elttype, elt, elt_strict))
14049 /* If the std::initializer_list<T> deduction worked, replace the
14050 deduced A with std::initializer_list<A>. */
14051 if (orig_parm != parm)
14053 idx = TEMPLATE_TYPE_IDX (orig_parm);
14054 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14055 targ = listify (targ);
14056 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
14061 /* Immediately reject some pairs that won't unify because of
14062 cv-qualification mismatches. */
14063 if (TREE_CODE (arg) == TREE_CODE (parm)
14065 /* It is the elements of the array which hold the cv quals of an array
14066 type, and the elements might be template type parms. We'll check
14067 when we recurse. */
14068 && TREE_CODE (arg) != ARRAY_TYPE
14069 /* We check the cv-qualifiers when unifying with template type
14070 parameters below. We want to allow ARG `const T' to unify with
14071 PARM `T' for example, when computing which of two templates
14072 is more specialized, for example. */
14073 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
14074 && !check_cv_quals_for_unify (strict_in, arg, parm))
14077 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
14078 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
14079 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
14080 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
14081 strict &= ~UNIFY_ALLOW_DERIVED;
14082 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14083 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
14085 switch (TREE_CODE (parm))
14087 case TYPENAME_TYPE:
14089 case UNBOUND_CLASS_TEMPLATE:
14090 /* In a type which contains a nested-name-specifier, template
14091 argument values cannot be deduced for template parameters used
14092 within the nested-name-specifier. */
14095 case TEMPLATE_TYPE_PARM:
14096 case TEMPLATE_TEMPLATE_PARM:
14097 case BOUND_TEMPLATE_TEMPLATE_PARM:
14098 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14099 if (tparm == error_mark_node)
14102 if (TEMPLATE_TYPE_LEVEL (parm)
14103 != template_decl_level (tparm))
14104 /* The PARM is not one we're trying to unify. Just check
14105 to see if it matches ARG. */
14106 return (TREE_CODE (arg) == TREE_CODE (parm)
14107 && same_type_p (parm, arg)) ? 0 : 1;
14108 idx = TEMPLATE_TYPE_IDX (parm);
14109 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14110 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
14112 /* Check for mixed types and values. */
14113 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14114 && TREE_CODE (tparm) != TYPE_DECL)
14115 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14116 && TREE_CODE (tparm) != TEMPLATE_DECL))
14119 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14121 /* ARG must be constructed from a template class or a template
14122 template parameter. */
14123 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
14124 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
14128 tree parmvec = TYPE_TI_ARGS (parm);
14129 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
14131 = DECL_INNERMOST_TEMPLATE_PARMS
14132 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
14134 int parm_variadic_p = 0;
14136 /* The resolution to DR150 makes clear that default
14137 arguments for an N-argument may not be used to bind T
14138 to a template template parameter with fewer than N
14139 parameters. It is not safe to permit the binding of
14140 default arguments as an extension, as that may change
14141 the meaning of a conforming program. Consider:
14143 struct Dense { static const unsigned int dim = 1; };
14145 template <template <typename> class View,
14147 void operator+(float, View<Block> const&);
14149 template <typename Block,
14150 unsigned int Dim = Block::dim>
14151 struct Lvalue_proxy { operator float() const; };
14155 Lvalue_proxy<Dense> p;
14160 Here, if Lvalue_proxy is permitted to bind to View, then
14161 the global operator+ will be used; if they are not, the
14162 Lvalue_proxy will be converted to float. */
14163 if (coerce_template_parms (parm_parms,
14165 TYPE_TI_TEMPLATE (parm),
14167 /*require_all_args=*/true,
14168 /*use_default_args=*/false)
14169 == error_mark_node)
14172 /* Deduce arguments T, i from TT<T> or TT<i>.
14173 We check each element of PARMVEC and ARGVEC individually
14174 rather than the whole TREE_VEC since they can have
14175 different number of elements. */
14177 parmvec = expand_template_argument_pack (parmvec);
14178 argvec = expand_template_argument_pack (argvec);
14180 len = TREE_VEC_LENGTH (parmvec);
14182 /* Check if the parameters end in a pack, making them
14185 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
14186 parm_variadic_p = 1;
14188 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
14191 for (i = 0; i < len - parm_variadic_p; ++i)
14193 if (unify (tparms, targs,
14194 TREE_VEC_ELT (parmvec, i),
14195 TREE_VEC_ELT (argvec, i),
14200 if (parm_variadic_p
14201 && unify_pack_expansion (tparms, targs,
14204 /*call_args_p=*/false,
14208 arg = TYPE_TI_TEMPLATE (arg);
14210 /* Fall through to deduce template name. */
14213 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14214 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14216 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
14218 /* Simple cases: Value already set, does match or doesn't. */
14219 if (targ != NULL_TREE && template_args_equal (targ, arg))
14226 /* If PARM is `const T' and ARG is only `int', we don't have
14227 a match unless we are allowing additional qualification.
14228 If ARG is `const int' and PARM is just `T' that's OK;
14229 that binds `const int' to `T'. */
14230 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
14234 /* Consider the case where ARG is `const volatile int' and
14235 PARM is `const T'. Then, T should be `volatile int'. */
14236 arg = cp_build_qualified_type_real
14237 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
14238 if (arg == error_mark_node)
14241 /* Simple cases: Value already set, does match or doesn't. */
14242 if (targ != NULL_TREE && same_type_p (targ, arg))
14247 /* Make sure that ARG is not a variable-sized array. (Note
14248 that were talking about variable-sized arrays (like
14249 `int[n]'), rather than arrays of unknown size (like
14250 `int[]').) We'll get very confused by such a type since
14251 the bound of the array will not be computable in an
14252 instantiation. Besides, such types are not allowed in
14253 ISO C++, so we can do as we please here. */
14254 if (variably_modified_type_p (arg, NULL_TREE))
14257 /* Strip typedefs as in convert_template_argument. */
14258 arg = strip_typedefs (arg);
14261 /* If ARG is a parameter pack or an expansion, we cannot unify
14262 against it unless PARM is also a parameter pack. */
14263 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
14264 && !template_parameter_pack_p (parm))
14267 /* If the argument deduction results is a METHOD_TYPE,
14268 then there is a problem.
14269 METHOD_TYPE doesn't map to any real C++ type the result of
14270 the deduction can not be of that type. */
14271 if (TREE_CODE (arg) == METHOD_TYPE)
14274 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
14277 case TEMPLATE_PARM_INDEX:
14278 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14279 if (tparm == error_mark_node)
14282 if (TEMPLATE_PARM_LEVEL (parm)
14283 != template_decl_level (tparm))
14284 /* The PARM is not one we're trying to unify. Just check
14285 to see if it matches ARG. */
14286 return !(TREE_CODE (arg) == TREE_CODE (parm)
14287 && cp_tree_equal (parm, arg));
14289 idx = TEMPLATE_PARM_IDX (parm);
14290 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14293 return !cp_tree_equal (targ, arg);
14295 /* [temp.deduct.type] If, in the declaration of a function template
14296 with a non-type template-parameter, the non-type
14297 template-parameter is used in an expression in the function
14298 parameter-list and, if the corresponding template-argument is
14299 deduced, the template-argument type shall match the type of the
14300 template-parameter exactly, except that a template-argument
14301 deduced from an array bound may be of any integral type.
14302 The non-type parameter might use already deduced type parameters. */
14303 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
14304 if (!TREE_TYPE (arg))
14305 /* Template-parameter dependent expression. Just accept it for now.
14306 It will later be processed in convert_template_argument. */
14308 else if (same_type_p (TREE_TYPE (arg), tparm))
14310 else if ((strict & UNIFY_ALLOW_INTEGER)
14311 && (TREE_CODE (tparm) == INTEGER_TYPE
14312 || TREE_CODE (tparm) == BOOLEAN_TYPE))
14313 /* Convert the ARG to the type of PARM; the deduced non-type
14314 template argument must exactly match the types of the
14315 corresponding parameter. */
14316 arg = fold (build_nop (tparm, arg));
14317 else if (uses_template_parms (tparm))
14318 /* We haven't deduced the type of this parameter yet. Try again
14324 /* If ARG is a parameter pack or an expansion, we cannot unify
14325 against it unless PARM is also a parameter pack. */
14326 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
14327 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
14330 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
14335 /* A pointer-to-member constant can be unified only with
14336 another constant. */
14337 if (TREE_CODE (arg) != PTRMEM_CST)
14340 /* Just unify the class member. It would be useless (and possibly
14341 wrong, depending on the strict flags) to unify also
14342 PTRMEM_CST_CLASS, because we want to be sure that both parm and
14343 arg refer to the same variable, even if through different
14344 classes. For instance:
14346 struct A { int x; };
14349 Unification of &A::x and &B::x must succeed. */
14350 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
14351 PTRMEM_CST_MEMBER (arg), strict);
14356 if (TREE_CODE (arg) != POINTER_TYPE)
14359 /* [temp.deduct.call]
14361 A can be another pointer or pointer to member type that can
14362 be converted to the deduced A via a qualification
14363 conversion (_conv.qual_).
14365 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
14366 This will allow for additional cv-qualification of the
14367 pointed-to types if appropriate. */
14369 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
14370 /* The derived-to-base conversion only persists through one
14371 level of pointers. */
14372 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
14374 return unify (tparms, targs, TREE_TYPE (parm),
14375 TREE_TYPE (arg), strict);
14378 case REFERENCE_TYPE:
14379 if (TREE_CODE (arg) != REFERENCE_TYPE)
14381 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14382 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14385 if (TREE_CODE (arg) != ARRAY_TYPE)
14387 if ((TYPE_DOMAIN (parm) == NULL_TREE)
14388 != (TYPE_DOMAIN (arg) == NULL_TREE))
14390 if (TYPE_DOMAIN (parm) != NULL_TREE)
14397 /* Our representation of array types uses "N - 1" as the
14398 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
14399 not an integer constant. We cannot unify arbitrarily
14400 complex expressions, so we eliminate the MINUS_EXPRs
14402 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
14403 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
14406 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
14407 parm_max = TREE_OPERAND (parm_max, 0);
14409 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
14410 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
14413 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
14414 trying to unify the type of a variable with the type
14415 of a template parameter. For example:
14417 template <unsigned int N>
14418 void f (char (&) [N]);
14425 Here, the type of the ARG will be "int [g(i)]", and
14426 may be a SAVE_EXPR, etc. */
14427 if (TREE_CODE (arg_max) != MINUS_EXPR)
14429 arg_max = TREE_OPERAND (arg_max, 0);
14432 /* If only one of the bounds used a MINUS_EXPR, compensate
14433 by adding one to the other bound. */
14434 if (parm_cst && !arg_cst)
14435 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
14439 else if (arg_cst && !parm_cst)
14440 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
14445 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
14448 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14449 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14456 case ENUMERAL_TYPE:
14458 if (TREE_CODE (arg) != TREE_CODE (parm))
14461 /* We have already checked cv-qualification at the top of the
14463 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
14466 /* As far as unification is concerned, this wins. Later checks
14467 will invalidate it if necessary. */
14470 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
14471 /* Type INTEGER_CST can come from ordinary constant template args. */
14473 while (TREE_CODE (arg) == NOP_EXPR)
14474 arg = TREE_OPERAND (arg, 0);
14476 if (TREE_CODE (arg) != INTEGER_CST)
14478 return !tree_int_cst_equal (parm, arg);
14483 if (TREE_CODE (arg) != TREE_VEC)
14485 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
14487 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
14488 if (unify (tparms, targs,
14489 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
14497 if (TREE_CODE (arg) != TREE_CODE (parm))
14500 if (TYPE_PTRMEMFUNC_P (parm))
14502 if (!TYPE_PTRMEMFUNC_P (arg))
14505 return unify (tparms, targs,
14506 TYPE_PTRMEMFUNC_FN_TYPE (parm),
14507 TYPE_PTRMEMFUNC_FN_TYPE (arg),
14511 if (CLASSTYPE_TEMPLATE_INFO (parm))
14513 tree t = NULL_TREE;
14515 if (strict_in & UNIFY_ALLOW_DERIVED)
14517 /* First, we try to unify the PARM and ARG directly. */
14518 t = try_class_unification (tparms, targs,
14523 /* Fallback to the special case allowed in
14524 [temp.deduct.call]:
14526 If P is a class, and P has the form
14527 template-id, then A can be a derived class of
14528 the deduced A. Likewise, if P is a pointer to
14529 a class of the form template-id, A can be a
14530 pointer to a derived class pointed to by the
14532 t = get_template_base (tparms, targs, parm, arg);
14538 else if (CLASSTYPE_TEMPLATE_INFO (arg)
14539 && (CLASSTYPE_TI_TEMPLATE (parm)
14540 == CLASSTYPE_TI_TEMPLATE (arg)))
14541 /* Perhaps PARM is something like S<U> and ARG is S<int>.
14542 Then, we should unify `int' and `U'. */
14545 /* There's no chance of unification succeeding. */
14548 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
14549 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
14551 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
14556 case FUNCTION_TYPE:
14558 unsigned int nargs;
14563 if (TREE_CODE (arg) != TREE_CODE (parm))
14566 /* CV qualifications for methods can never be deduced, they must
14567 match exactly. We need to check them explicitly here,
14568 because type_unification_real treats them as any other
14569 cv-qualified parameter. */
14570 if (TREE_CODE (parm) == METHOD_TYPE
14571 && (!check_cv_quals_for_unify
14573 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
14574 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
14577 if (unify (tparms, targs, TREE_TYPE (parm),
14578 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
14581 nargs = list_length (TYPE_ARG_TYPES (arg));
14582 args = XALLOCAVEC (tree, nargs);
14583 for (a = TYPE_ARG_TYPES (arg), i = 0;
14584 a != NULL_TREE && a != void_list_node;
14585 a = TREE_CHAIN (a), ++i)
14586 args[i] = TREE_VALUE (a);
14589 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
14590 args, nargs, 1, DEDUCE_EXACT,
14595 /* Unify a pointer to member with a pointer to member function, which
14596 deduces the type of the member as a function type. */
14597 if (TYPE_PTRMEMFUNC_P (arg))
14601 cp_cv_quals cv_quals;
14603 /* Check top-level cv qualifiers */
14604 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
14607 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14608 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
14611 /* Determine the type of the function we are unifying against. */
14612 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
14614 build_function_type (TREE_TYPE (method_type),
14615 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
14617 /* Extract the cv-qualifiers of the member function from the
14618 implicit object parameter and place them on the function
14619 type to be restored later. */
14621 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
14622 fntype = build_qualified_type (fntype, cv_quals);
14623 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
14626 if (TREE_CODE (arg) != OFFSET_TYPE)
14628 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14629 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
14631 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14635 if (DECL_TEMPLATE_PARM_P (parm))
14636 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
14637 if (arg != integral_constant_value (parm))
14642 case TEMPLATE_DECL:
14643 /* Matched cases are handled by the ARG == PARM test above. */
14646 case TYPE_ARGUMENT_PACK:
14647 case NONTYPE_ARGUMENT_PACK:
14649 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
14650 tree packed_args = ARGUMENT_PACK_ARGS (arg);
14651 int i, len = TREE_VEC_LENGTH (packed_parms);
14652 int argslen = TREE_VEC_LENGTH (packed_args);
14653 int parm_variadic_p = 0;
14655 for (i = 0; i < len; ++i)
14657 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
14660 /* We can unify against something with a trailing
14662 parm_variadic_p = 1;
14664 /* Since there is something following the pack
14665 expansion, we cannot unify this template argument
14672 /* If we don't have enough arguments to satisfy the parameters
14673 (not counting the pack expression at the end), or we have
14674 too many arguments for a parameter list that doesn't end in
14675 a pack expression, we can't unify. */
14676 if (argslen < (len - parm_variadic_p)
14677 || (argslen > len && !parm_variadic_p))
14680 /* Unify all of the parameters that precede the (optional)
14681 pack expression. */
14682 for (i = 0; i < len - parm_variadic_p; ++i)
14684 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
14685 TREE_VEC_ELT (packed_args, i), strict))
14689 if (parm_variadic_p)
14690 return unify_pack_expansion (tparms, targs,
14691 packed_parms, packed_args,
14692 strict, /*call_args_p=*/false,
14700 case DECLTYPE_TYPE:
14701 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
14706 /* Unification fails if we hit an error node. */
14710 gcc_assert (EXPR_P (parm));
14712 /* We must be looking at an expression. This can happen with
14716 void foo(S<I>, S<I + 2>);
14718 This is a "nondeduced context":
14722 The nondeduced contexts are:
14724 --A type that is a template-id in which one or more of
14725 the template-arguments is an expression that references
14726 a template-parameter.
14728 In these cases, we assume deduction succeeded, but don't
14729 actually infer any unifications. */
14731 if (!uses_template_parms (parm)
14732 && !template_args_equal (parm, arg))
14739 /* Note that DECL can be defined in this translation unit, if
14743 mark_definable (tree decl)
14746 DECL_NOT_REALLY_EXTERN (decl) = 1;
14747 FOR_EACH_CLONE (clone, decl)
14748 DECL_NOT_REALLY_EXTERN (clone) = 1;
14751 /* Called if RESULT is explicitly instantiated, or is a member of an
14752 explicitly instantiated class. */
14755 mark_decl_instantiated (tree result, int extern_p)
14757 SET_DECL_EXPLICIT_INSTANTIATION (result);
14759 /* If this entity has already been written out, it's too late to
14760 make any modifications. */
14761 if (TREE_ASM_WRITTEN (result))
14764 if (TREE_CODE (result) != FUNCTION_DECL)
14765 /* The TREE_PUBLIC flag for function declarations will have been
14766 set correctly by tsubst. */
14767 TREE_PUBLIC (result) = 1;
14769 /* This might have been set by an earlier implicit instantiation. */
14770 DECL_COMDAT (result) = 0;
14773 DECL_NOT_REALLY_EXTERN (result) = 0;
14776 mark_definable (result);
14777 /* Always make artificials weak. */
14778 if (DECL_ARTIFICIAL (result) && flag_weak)
14779 comdat_linkage (result);
14780 /* For WIN32 we also want to put explicit instantiations in
14781 linkonce sections. */
14782 else if (TREE_PUBLIC (result))
14783 maybe_make_one_only (result);
14786 /* If EXTERN_P, then this function will not be emitted -- unless
14787 followed by an explicit instantiation, at which point its linkage
14788 will be adjusted. If !EXTERN_P, then this function will be
14789 emitted here. In neither circumstance do we want
14790 import_export_decl to adjust the linkage. */
14791 DECL_INTERFACE_KNOWN (result) = 1;
14794 /* Given two function templates PAT1 and PAT2, return:
14796 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
14797 -1 if PAT2 is more specialized than PAT1.
14798 0 if neither is more specialized.
14800 LEN indicates the number of parameters we should consider
14801 (defaulted parameters should not be considered).
14803 The 1998 std underspecified function template partial ordering, and
14804 DR214 addresses the issue. We take pairs of arguments, one from
14805 each of the templates, and deduce them against each other. One of
14806 the templates will be more specialized if all the *other*
14807 template's arguments deduce against its arguments and at least one
14808 of its arguments *does* *not* deduce against the other template's
14809 corresponding argument. Deduction is done as for class templates.
14810 The arguments used in deduction have reference and top level cv
14811 qualifiers removed. Iff both arguments were originally reference
14812 types *and* deduction succeeds in both directions, the template
14813 with the more cv-qualified argument wins for that pairing (if
14814 neither is more cv-qualified, they both are equal). Unlike regular
14815 deduction, after all the arguments have been deduced in this way,
14816 we do *not* verify the deduced template argument values can be
14817 substituted into non-deduced contexts, nor do we have to verify
14818 that all template arguments have been deduced. */
14821 more_specialized_fn (tree pat1, tree pat2, int len)
14823 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
14824 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
14825 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
14826 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
14827 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
14828 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
14829 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
14830 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
14834 /* Remove the this parameter from non-static member functions. If
14835 one is a non-static member function and the other is not a static
14836 member function, remove the first parameter from that function
14837 also. This situation occurs for operator functions where we
14838 locate both a member function (with this pointer) and non-member
14839 operator (with explicit first operand). */
14840 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
14842 len--; /* LEN is the number of significant arguments for DECL1 */
14843 args1 = TREE_CHAIN (args1);
14844 if (!DECL_STATIC_FUNCTION_P (decl2))
14845 args2 = TREE_CHAIN (args2);
14847 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
14849 args2 = TREE_CHAIN (args2);
14850 if (!DECL_STATIC_FUNCTION_P (decl1))
14853 args1 = TREE_CHAIN (args1);
14857 /* If only one is a conversion operator, they are unordered. */
14858 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
14861 /* Consider the return type for a conversion function */
14862 if (DECL_CONV_FN_P (decl1))
14864 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
14865 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
14869 processing_template_decl++;
14872 /* Stop when an ellipsis is seen. */
14873 && args1 != NULL_TREE && args2 != NULL_TREE)
14875 tree arg1 = TREE_VALUE (args1);
14876 tree arg2 = TREE_VALUE (args2);
14877 int deduce1, deduce2;
14881 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
14882 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
14884 /* When both arguments are pack expansions, we need only
14885 unify the patterns themselves. */
14886 arg1 = PACK_EXPANSION_PATTERN (arg1);
14887 arg2 = PACK_EXPANSION_PATTERN (arg2);
14889 /* This is the last comparison we need to do. */
14893 if (TREE_CODE (arg1) == REFERENCE_TYPE)
14895 arg1 = TREE_TYPE (arg1);
14896 quals1 = cp_type_quals (arg1);
14899 if (TREE_CODE (arg2) == REFERENCE_TYPE)
14901 arg2 = TREE_TYPE (arg2);
14902 quals2 = cp_type_quals (arg2);
14905 if ((quals1 < 0) != (quals2 < 0))
14907 /* Only of the args is a reference, see if we should apply
14908 array/function pointer decay to it. This is not part of
14909 DR214, but is, IMHO, consistent with the deduction rules
14910 for the function call itself, and with our earlier
14911 implementation of the underspecified partial ordering
14912 rules. (nathan). */
14915 switch (TREE_CODE (arg1))
14918 arg1 = TREE_TYPE (arg1);
14920 case FUNCTION_TYPE:
14921 arg1 = build_pointer_type (arg1);
14930 switch (TREE_CODE (arg2))
14933 arg2 = TREE_TYPE (arg2);
14935 case FUNCTION_TYPE:
14936 arg2 = build_pointer_type (arg2);
14945 arg1 = TYPE_MAIN_VARIANT (arg1);
14946 arg2 = TYPE_MAIN_VARIANT (arg2);
14948 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
14950 int i, len2 = list_length (args2);
14951 tree parmvec = make_tree_vec (1);
14952 tree argvec = make_tree_vec (len2);
14955 /* Setup the parameter vector, which contains only ARG1. */
14956 TREE_VEC_ELT (parmvec, 0) = arg1;
14958 /* Setup the argument vector, which contains the remaining
14960 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
14961 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
14963 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
14964 argvec, UNIFY_ALLOW_NONE,
14965 /*call_args_p=*/false,
14968 /* We cannot deduce in the other direction, because ARG1 is
14969 a pack expansion but ARG2 is not. */
14972 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
14974 int i, len1 = list_length (args1);
14975 tree parmvec = make_tree_vec (1);
14976 tree argvec = make_tree_vec (len1);
14979 /* Setup the parameter vector, which contains only ARG1. */
14980 TREE_VEC_ELT (parmvec, 0) = arg2;
14982 /* Setup the argument vector, which contains the remaining
14984 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
14985 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
14987 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
14988 argvec, UNIFY_ALLOW_NONE,
14989 /*call_args_p=*/false,
14992 /* We cannot deduce in the other direction, because ARG2 is
14993 a pack expansion but ARG1 is not.*/
14999 /* The normal case, where neither argument is a pack
15001 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
15002 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
15009 if (better1 < 0 && better2 < 0)
15010 /* We've failed to deduce something in either direction.
15011 These must be unordered. */
15014 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
15016 /* Deduces in both directions, see if quals can
15017 disambiguate. Pretend the worse one failed to deduce. */
15018 if ((quals1 & quals2) == quals2)
15020 if ((quals1 & quals2) == quals1)
15023 if (deduce1 && !deduce2 && !better2)
15025 if (deduce2 && !deduce1 && !better1)
15028 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
15029 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15030 /* We have already processed all of the arguments in our
15031 handing of the pack expansion type. */
15034 args1 = TREE_CHAIN (args1);
15035 args2 = TREE_CHAIN (args2);
15038 processing_template_decl--;
15040 /* All things being equal, if the next argument is a pack expansion
15041 for one function but not for the other, prefer the
15042 non-variadic function. */
15043 if ((better1 > 0) - (better2 > 0) == 0
15044 && args1 && TREE_VALUE (args1)
15045 && args2 && TREE_VALUE (args2))
15047 if (TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION)
15048 return TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION ? 0 : -1;
15049 else if (TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION)
15053 return (better1 > 0) - (better2 > 0);
15056 /* Determine which of two partial specializations is more specialized.
15058 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
15059 to the first partial specialization. The TREE_VALUE is the
15060 innermost set of template parameters for the partial
15061 specialization. PAT2 is similar, but for the second template.
15063 Return 1 if the first partial specialization is more specialized;
15064 -1 if the second is more specialized; 0 if neither is more
15067 See [temp.class.order] for information about determining which of
15068 two templates is more specialized. */
15071 more_specialized_class (tree pat1, tree pat2)
15076 bool any_deductions = false;
15078 tmpl1 = TREE_TYPE (pat1);
15079 tmpl2 = TREE_TYPE (pat2);
15081 /* Just like what happens for functions, if we are ordering between
15082 different class template specializations, we may encounter dependent
15083 types in the arguments, and we need our dependency check functions
15084 to behave correctly. */
15085 ++processing_template_decl;
15086 targs = get_class_bindings (TREE_VALUE (pat1),
15087 CLASSTYPE_TI_ARGS (tmpl1),
15088 CLASSTYPE_TI_ARGS (tmpl2));
15092 any_deductions = true;
15095 targs = get_class_bindings (TREE_VALUE (pat2),
15096 CLASSTYPE_TI_ARGS (tmpl2),
15097 CLASSTYPE_TI_ARGS (tmpl1));
15101 any_deductions = true;
15103 --processing_template_decl;
15105 /* In the case of a tie where at least one of the class templates
15106 has a parameter pack at the end, the template with the most
15107 non-packed parameters wins. */
15110 && (template_args_variadic_p (TREE_PURPOSE (pat1))
15111 || template_args_variadic_p (TREE_PURPOSE (pat2))))
15113 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
15114 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
15115 int len1 = TREE_VEC_LENGTH (args1);
15116 int len2 = TREE_VEC_LENGTH (args2);
15118 /* We don't count the pack expansion at the end. */
15119 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
15121 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
15126 else if (len1 < len2)
15133 /* Return the template arguments that will produce the function signature
15134 DECL from the function template FN, with the explicit template
15135 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
15136 also match. Return NULL_TREE if no satisfactory arguments could be
15140 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
15142 int ntparms = DECL_NTPARMS (fn);
15143 tree targs = make_tree_vec (ntparms);
15145 tree decl_arg_types;
15147 unsigned int nargs, ix;
15150 /* Substitute the explicit template arguments into the type of DECL.
15151 The call to fn_type_unification will handle substitution into the
15153 decl_type = TREE_TYPE (decl);
15154 if (explicit_args && uses_template_parms (decl_type))
15157 tree converted_args;
15159 if (DECL_TEMPLATE_INFO (decl))
15160 tmpl = DECL_TI_TEMPLATE (decl);
15162 /* We can get here for some invalid specializations. */
15166 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
15167 explicit_args, NULL_TREE,
15169 /*require_all_args=*/false,
15170 /*use_default_args=*/false);
15171 if (converted_args == error_mark_node)
15174 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
15175 if (decl_type == error_mark_node)
15179 /* Never do unification on the 'this' parameter. */
15180 decl_arg_types = skip_artificial_parms_for (decl,
15181 TYPE_ARG_TYPES (decl_type));
15183 nargs = list_length (decl_arg_types);
15184 args = XALLOCAVEC (tree, nargs);
15185 for (arg = decl_arg_types, ix = 0;
15186 arg != NULL_TREE && arg != void_list_node;
15187 arg = TREE_CHAIN (arg), ++ix)
15188 args[ix] = TREE_VALUE (arg);
15190 if (fn_type_unification (fn, explicit_args, targs,
15192 (check_rettype || DECL_CONV_FN_P (fn)
15193 ? TREE_TYPE (decl_type) : NULL_TREE),
15194 DEDUCE_EXACT, LOOKUP_NORMAL))
15200 /* Return the innermost template arguments that, when applied to a
15201 template specialization whose innermost template parameters are
15202 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
15205 For example, suppose we have:
15207 template <class T, class U> struct S {};
15208 template <class T> struct S<T*, int> {};
15210 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
15211 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
15212 int}. The resulting vector will be {double}, indicating that `T'
15213 is bound to `double'. */
15216 get_class_bindings (tree tparms, tree spec_args, tree args)
15218 int i, ntparms = TREE_VEC_LENGTH (tparms);
15220 tree innermost_deduced_args;
15222 innermost_deduced_args = make_tree_vec (ntparms);
15223 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15225 deduced_args = copy_node (args);
15226 SET_TMPL_ARGS_LEVEL (deduced_args,
15227 TMPL_ARGS_DEPTH (deduced_args),
15228 innermost_deduced_args);
15231 deduced_args = innermost_deduced_args;
15233 if (unify (tparms, deduced_args,
15234 INNERMOST_TEMPLATE_ARGS (spec_args),
15235 INNERMOST_TEMPLATE_ARGS (args),
15239 for (i = 0; i < ntparms; ++i)
15240 if (! TREE_VEC_ELT (innermost_deduced_args, i))
15243 /* Verify that nondeduced template arguments agree with the type
15244 obtained from argument deduction.
15248 struct A { typedef int X; };
15249 template <class T, class U> struct C {};
15250 template <class T> struct C<T, typename T::X> {};
15252 Then with the instantiation `C<A, int>', we can deduce that
15253 `T' is `A' but unify () does not check whether `typename T::X'
15255 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
15256 if (spec_args == error_mark_node
15257 /* We only need to check the innermost arguments; the other
15258 arguments will always agree. */
15259 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
15260 INNERMOST_TEMPLATE_ARGS (args)))
15263 /* Now that we have bindings for all of the template arguments,
15264 ensure that the arguments deduced for the template template
15265 parameters have compatible template parameter lists. See the use
15266 of template_template_parm_bindings_ok_p in fn_type_unification
15267 for more information. */
15268 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
15271 return deduced_args;
15274 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
15275 Return the TREE_LIST node with the most specialized template, if
15276 any. If there is no most specialized template, the error_mark_node
15279 Note that this function does not look at, or modify, the
15280 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
15281 returned is one of the elements of INSTANTIATIONS, callers may
15282 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
15283 and retrieve it from the value returned. */
15286 most_specialized_instantiation (tree templates)
15290 ++processing_template_decl;
15293 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
15297 if (get_bindings (TREE_VALUE (champ),
15298 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
15299 NULL_TREE, /*check_ret=*/false))
15302 if (get_bindings (TREE_VALUE (fn),
15303 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
15304 NULL_TREE, /*check_ret=*/false))
15311 /* Equally specialized, move to next function. If there
15312 is no next function, nothing's most specialized. */
15313 fn = TREE_CHAIN (fn);
15321 /* Now verify that champ is better than everything earlier in the
15322 instantiation list. */
15323 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
15324 if (get_bindings (TREE_VALUE (champ),
15325 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
15326 NULL_TREE, /*check_ret=*/false)
15327 || !get_bindings (TREE_VALUE (fn),
15328 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
15329 NULL_TREE, /*check_ret=*/false))
15335 processing_template_decl--;
15338 return error_mark_node;
15343 /* If DECL is a specialization of some template, return the most
15344 general such template. Otherwise, returns NULL_TREE.
15346 For example, given:
15348 template <class T> struct S { template <class U> void f(U); };
15350 if TMPL is `template <class U> void S<int>::f(U)' this will return
15351 the full template. This function will not trace past partial
15352 specializations, however. For example, given in addition:
15354 template <class T> struct S<T*> { template <class U> void f(U); };
15356 if TMPL is `template <class U> void S<int*>::f(U)' this will return
15357 `template <class T> template <class U> S<T*>::f(U)'. */
15360 most_general_template (tree decl)
15362 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
15363 an immediate specialization. */
15364 if (TREE_CODE (decl) == FUNCTION_DECL)
15366 if (DECL_TEMPLATE_INFO (decl)) {
15367 decl = DECL_TI_TEMPLATE (decl);
15369 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
15370 template friend. */
15371 if (TREE_CODE (decl) != TEMPLATE_DECL)
15377 /* Look for more and more general templates. */
15378 while (DECL_TEMPLATE_INFO (decl))
15380 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
15381 (See cp-tree.h for details.) */
15382 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
15385 if (CLASS_TYPE_P (TREE_TYPE (decl))
15386 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
15389 /* Stop if we run into an explicitly specialized class template. */
15390 if (!DECL_NAMESPACE_SCOPE_P (decl)
15391 && DECL_CONTEXT (decl)
15392 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
15395 decl = DECL_TI_TEMPLATE (decl);
15401 /* Return the most specialized of the class template partial
15402 specializations of TMPL which can produce TYPE, a specialization of
15403 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
15404 a _TYPE node corresponding to the partial specialization, while the
15405 TREE_PURPOSE is the set of template arguments that must be
15406 substituted into the TREE_TYPE in order to generate TYPE.
15408 If the choice of partial specialization is ambiguous, a diagnostic
15409 is issued, and the error_mark_node is returned. If there are no
15410 partial specializations of TMPL matching TYPE, then NULL_TREE is
15414 most_specialized_class (tree type, tree tmpl)
15416 tree list = NULL_TREE;
15422 tree outer_args = NULL_TREE;
15424 tmpl = most_general_template (tmpl);
15425 args = CLASSTYPE_TI_ARGS (type);
15427 /* For determining which partial specialization to use, only the
15428 innermost args are interesting. */
15429 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15431 outer_args = strip_innermost_template_args (args, 1);
15432 args = INNERMOST_TEMPLATE_ARGS (args);
15435 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
15437 tree partial_spec_args;
15439 tree parms = TREE_VALUE (t);
15441 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
15446 ++processing_template_decl;
15448 /* Discard the outer levels of args, and then substitute in the
15449 template args from the enclosing class. */
15450 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
15451 partial_spec_args = tsubst_template_args
15452 (partial_spec_args, outer_args, tf_none, NULL_TREE);
15454 /* PARMS already refers to just the innermost parms, but the
15455 template parms in partial_spec_args had their levels lowered
15456 by tsubst, so we need to do the same for the parm list. We
15457 can't just tsubst the TREE_VEC itself, as tsubst wants to
15458 treat a TREE_VEC as an argument vector. */
15459 parms = copy_node (parms);
15460 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
15461 TREE_VEC_ELT (parms, i) =
15462 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
15464 --processing_template_decl;
15466 spec_args = get_class_bindings (parms,
15472 spec_args = add_to_template_args (outer_args, spec_args);
15473 list = tree_cons (spec_args, TREE_VALUE (t), list);
15474 TREE_TYPE (list) = TREE_TYPE (t);
15481 ambiguous_p = false;
15484 t = TREE_CHAIN (t);
15485 for (; t; t = TREE_CHAIN (t))
15487 fate = more_specialized_class (champ, t);
15494 t = TREE_CHAIN (t);
15497 ambiguous_p = true;
15506 for (t = list; t && t != champ; t = TREE_CHAIN (t))
15508 fate = more_specialized_class (champ, t);
15511 ambiguous_p = true;
15518 const char *str = "candidates are:";
15519 error ("ambiguous class template instantiation for %q#T", type);
15520 for (t = list; t; t = TREE_CHAIN (t))
15522 error ("%s %+#T", str, TREE_TYPE (t));
15525 return error_mark_node;
15531 /* Explicitly instantiate DECL. */
15534 do_decl_instantiation (tree decl, tree storage)
15536 tree result = NULL_TREE;
15539 if (!decl || decl == error_mark_node)
15540 /* An error occurred, for which grokdeclarator has already issued
15541 an appropriate message. */
15543 else if (! DECL_LANG_SPECIFIC (decl))
15545 error ("explicit instantiation of non-template %q#D", decl);
15548 else if (TREE_CODE (decl) == VAR_DECL)
15550 /* There is an asymmetry here in the way VAR_DECLs and
15551 FUNCTION_DECLs are handled by grokdeclarator. In the case of
15552 the latter, the DECL we get back will be marked as a
15553 template instantiation, and the appropriate
15554 DECL_TEMPLATE_INFO will be set up. This does not happen for
15555 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
15556 should handle VAR_DECLs as it currently handles
15558 if (!DECL_CLASS_SCOPE_P (decl))
15560 error ("%qD is not a static data member of a class template", decl);
15563 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
15564 if (!result || TREE_CODE (result) != VAR_DECL)
15566 error ("no matching template for %qD found", decl);
15569 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
15571 error ("type %qT for explicit instantiation %qD does not match "
15572 "declared type %qT", TREE_TYPE (result), decl,
15577 else if (TREE_CODE (decl) != FUNCTION_DECL)
15579 error ("explicit instantiation of %q#D", decl);
15585 /* Check for various error cases. Note that if the explicit
15586 instantiation is valid the RESULT will currently be marked as an
15587 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
15588 until we get here. */
15590 if (DECL_TEMPLATE_SPECIALIZATION (result))
15592 /* DR 259 [temp.spec].
15594 Both an explicit instantiation and a declaration of an explicit
15595 specialization shall not appear in a program unless the explicit
15596 instantiation follows a declaration of the explicit specialization.
15598 For a given set of template parameters, if an explicit
15599 instantiation of a template appears after a declaration of an
15600 explicit specialization for that template, the explicit
15601 instantiation has no effect. */
15604 else if (DECL_EXPLICIT_INSTANTIATION (result))
15608 No program shall explicitly instantiate any template more
15611 We check DECL_NOT_REALLY_EXTERN so as not to complain when
15612 the first instantiation was `extern' and the second is not,
15613 and EXTERN_P for the opposite case. */
15614 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
15615 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
15616 /* If an "extern" explicit instantiation follows an ordinary
15617 explicit instantiation, the template is instantiated. */
15621 else if (!DECL_IMPLICIT_INSTANTIATION (result))
15623 error ("no matching template for %qD found", result);
15626 else if (!DECL_TEMPLATE_INFO (result))
15628 permerror (input_location, "explicit instantiation of non-template %q#D", result);
15632 if (storage == NULL_TREE)
15634 else if (storage == ridpointers[(int) RID_EXTERN])
15636 if (!in_system_header && (cxx_dialect == cxx98))
15637 pedwarn (input_location, OPT_pedantic,
15638 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
15643 error ("storage class %qD applied to template instantiation", storage);
15645 check_explicit_instantiation_namespace (result);
15646 mark_decl_instantiated (result, extern_p);
15648 instantiate_decl (result, /*defer_ok=*/1,
15649 /*expl_inst_class_mem_p=*/false);
15653 mark_class_instantiated (tree t, int extern_p)
15655 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
15656 SET_CLASSTYPE_INTERFACE_KNOWN (t);
15657 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
15658 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
15661 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
15662 rest_of_type_compilation (t, 1);
15666 /* Called from do_type_instantiation through binding_table_foreach to
15667 do recursive instantiation for the type bound in ENTRY. */
15669 bt_instantiate_type_proc (binding_entry entry, void *data)
15671 tree storage = *(tree *) data;
15673 if (MAYBE_CLASS_TYPE_P (entry->type)
15674 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
15675 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
15678 /* Called from do_type_instantiation to instantiate a member
15679 (a member function or a static member variable) of an
15680 explicitly instantiated class template. */
15682 instantiate_class_member (tree decl, int extern_p)
15684 mark_decl_instantiated (decl, extern_p);
15686 instantiate_decl (decl, /*defer_ok=*/1,
15687 /*expl_inst_class_mem_p=*/true);
15690 /* Perform an explicit instantiation of template class T. STORAGE, if
15691 non-null, is the RID for extern, inline or static. COMPLAIN is
15692 nonzero if this is called from the parser, zero if called recursively,
15693 since the standard is unclear (as detailed below). */
15696 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
15701 int previous_instantiation_extern_p = 0;
15703 if (TREE_CODE (t) == TYPE_DECL)
15706 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
15708 error ("explicit instantiation of non-template type %qT", t);
15714 if (!COMPLETE_TYPE_P (t))
15716 if (complain & tf_error)
15717 error ("explicit instantiation of %q#T before definition of template",
15722 if (storage != NULL_TREE)
15724 if (!in_system_header)
15726 if (storage == ridpointers[(int) RID_EXTERN])
15728 if (cxx_dialect == cxx98)
15729 pedwarn (input_location, OPT_pedantic,
15730 "ISO C++ 1998 forbids the use of %<extern%> on "
15731 "explicit instantiations");
15734 pedwarn (input_location, OPT_pedantic,
15735 "ISO C++ forbids the use of %qE"
15736 " on explicit instantiations", storage);
15739 if (storage == ridpointers[(int) RID_INLINE])
15741 else if (storage == ridpointers[(int) RID_EXTERN])
15743 else if (storage == ridpointers[(int) RID_STATIC])
15747 error ("storage class %qD applied to template instantiation",
15753 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
15755 /* DR 259 [temp.spec].
15757 Both an explicit instantiation and a declaration of an explicit
15758 specialization shall not appear in a program unless the explicit
15759 instantiation follows a declaration of the explicit specialization.
15761 For a given set of template parameters, if an explicit
15762 instantiation of a template appears after a declaration of an
15763 explicit specialization for that template, the explicit
15764 instantiation has no effect. */
15767 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
15771 No program shall explicitly instantiate any template more
15774 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
15775 instantiation was `extern'. If EXTERN_P then the second is.
15776 These cases are OK. */
15777 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
15779 if (!previous_instantiation_extern_p && !extern_p
15780 && (complain & tf_error))
15781 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
15783 /* If we've already instantiated the template, just return now. */
15784 if (!CLASSTYPE_INTERFACE_ONLY (t))
15788 check_explicit_instantiation_namespace (TYPE_NAME (t));
15789 mark_class_instantiated (t, extern_p);
15797 /* In contrast to implicit instantiation, where only the
15798 declarations, and not the definitions, of members are
15799 instantiated, we have here:
15803 The explicit instantiation of a class template specialization
15804 implies the instantiation of all of its members not
15805 previously explicitly specialized in the translation unit
15806 containing the explicit instantiation.
15808 Of course, we can't instantiate member template classes, since
15809 we don't have any arguments for them. Note that the standard
15810 is unclear on whether the instantiation of the members are
15811 *explicit* instantiations or not. However, the most natural
15812 interpretation is that it should be an explicit instantiation. */
15815 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
15816 if (TREE_CODE (tmp) == FUNCTION_DECL
15817 && DECL_TEMPLATE_INSTANTIATION (tmp))
15818 instantiate_class_member (tmp, extern_p);
15820 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
15821 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
15822 instantiate_class_member (tmp, extern_p);
15824 if (CLASSTYPE_NESTED_UTDS (t))
15825 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
15826 bt_instantiate_type_proc, &storage);
15830 /* Given a function DECL, which is a specialization of TMPL, modify
15831 DECL to be a re-instantiation of TMPL with the same template
15832 arguments. TMPL should be the template into which tsubst'ing
15833 should occur for DECL, not the most general template.
15835 One reason for doing this is a scenario like this:
15838 void f(const T&, int i);
15840 void g() { f(3, 7); }
15843 void f(const T& t, const int i) { }
15845 Note that when the template is first instantiated, with
15846 instantiate_template, the resulting DECL will have no name for the
15847 first parameter, and the wrong type for the second. So, when we go
15848 to instantiate the DECL, we regenerate it. */
15851 regenerate_decl_from_template (tree decl, tree tmpl)
15853 /* The arguments used to instantiate DECL, from the most general
15858 args = DECL_TI_ARGS (decl);
15859 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
15861 /* Make sure that we can see identifiers, and compute access
15863 push_access_scope (decl);
15865 if (TREE_CODE (decl) == FUNCTION_DECL)
15873 args_depth = TMPL_ARGS_DEPTH (args);
15874 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
15875 if (args_depth > parms_depth)
15876 args = get_innermost_template_args (args, parms_depth);
15878 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
15879 args, tf_error, NULL_TREE);
15881 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
15884 /* Merge parameter declarations. */
15885 decl_parm = skip_artificial_parms_for (decl,
15886 DECL_ARGUMENTS (decl));
15888 = skip_artificial_parms_for (code_pattern,
15889 DECL_ARGUMENTS (code_pattern));
15890 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
15895 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
15896 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
15897 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
15899 parm_type = type_decays_to (parm_type);
15900 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
15901 TREE_TYPE (decl_parm) = parm_type;
15902 attributes = DECL_ATTRIBUTES (pattern_parm);
15903 if (DECL_ATTRIBUTES (decl_parm) != attributes)
15905 DECL_ATTRIBUTES (decl_parm) = attributes;
15906 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
15908 decl_parm = TREE_CHAIN (decl_parm);
15909 pattern_parm = TREE_CHAIN (pattern_parm);
15911 /* Merge any parameters that match with the function parameter
15913 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
15916 tree expanded_types;
15917 /* Expand the TYPE_PACK_EXPANSION that provides the types for
15918 the parameters in this function parameter pack. */
15919 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
15920 args, tf_error, NULL_TREE);
15921 len = TREE_VEC_LENGTH (expanded_types);
15922 for (i = 0; i < len; i++)
15927 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
15928 /* Rename the parameter to include the index. */
15929 DECL_NAME (decl_parm) =
15930 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
15931 parm_type = TREE_VEC_ELT (expanded_types, i);
15932 parm_type = type_decays_to (parm_type);
15933 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
15934 TREE_TYPE (decl_parm) = parm_type;
15935 attributes = DECL_ATTRIBUTES (pattern_parm);
15936 if (DECL_ATTRIBUTES (decl_parm) != attributes)
15938 DECL_ATTRIBUTES (decl_parm) = attributes;
15939 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
15941 decl_parm = TREE_CHAIN (decl_parm);
15944 /* Merge additional specifiers from the CODE_PATTERN. */
15945 if (DECL_DECLARED_INLINE_P (code_pattern)
15946 && !DECL_DECLARED_INLINE_P (decl))
15947 DECL_DECLARED_INLINE_P (decl) = 1;
15949 else if (TREE_CODE (decl) == VAR_DECL)
15950 DECL_INITIAL (decl) =
15951 tsubst_expr (DECL_INITIAL (code_pattern), args,
15952 tf_error, DECL_TI_TEMPLATE (decl),
15953 /*integral_constant_expression_p=*/false);
15955 gcc_unreachable ();
15957 pop_access_scope (decl);
15960 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
15961 substituted to get DECL. */
15964 template_for_substitution (tree decl)
15966 tree tmpl = DECL_TI_TEMPLATE (decl);
15968 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
15969 for the instantiation. This is not always the most general
15970 template. Consider, for example:
15973 struct S { template <class U> void f();
15974 template <> void f<int>(); };
15976 and an instantiation of S<double>::f<int>. We want TD to be the
15977 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
15978 while (/* An instantiation cannot have a definition, so we need a
15979 more general template. */
15980 DECL_TEMPLATE_INSTANTIATION (tmpl)
15981 /* We must also deal with friend templates. Given:
15983 template <class T> struct S {
15984 template <class U> friend void f() {};
15987 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
15988 so far as the language is concerned, but that's still
15989 where we get the pattern for the instantiation from. On
15990 other hand, if the definition comes outside the class, say:
15992 template <class T> struct S {
15993 template <class U> friend void f();
15995 template <class U> friend void f() {}
15997 we don't need to look any further. That's what the check for
15998 DECL_INITIAL is for. */
15999 || (TREE_CODE (decl) == FUNCTION_DECL
16000 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
16001 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
16003 /* The present template, TD, should not be a definition. If it
16004 were a definition, we should be using it! Note that we
16005 cannot restructure the loop to just keep going until we find
16006 a template with a definition, since that might go too far if
16007 a specialization was declared, but not defined. */
16008 gcc_assert (TREE_CODE (decl) != VAR_DECL
16009 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
16011 /* Fetch the more general template. */
16012 tmpl = DECL_TI_TEMPLATE (tmpl);
16018 /* Returns true if we need to instantiate this template instance even if we
16019 know we aren't going to emit it.. */
16022 always_instantiate_p (tree decl)
16024 /* We always instantiate inline functions so that we can inline them. An
16025 explicit instantiation declaration prohibits implicit instantiation of
16026 non-inline functions. With high levels of optimization, we would
16027 normally inline non-inline functions -- but we're not allowed to do
16028 that for "extern template" functions. Therefore, we check
16029 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
16030 return ((TREE_CODE (decl) == FUNCTION_DECL
16031 && DECL_DECLARED_INLINE_P (decl))
16032 /* And we need to instantiate static data members so that
16033 their initializers are available in integral constant
16035 || (TREE_CODE (decl) == VAR_DECL
16036 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)));
16039 /* Produce the definition of D, a _DECL generated from a template. If
16040 DEFER_OK is nonzero, then we don't have to actually do the
16041 instantiation now; we just have to do it sometime. Normally it is
16042 an error if this is an explicit instantiation but D is undefined.
16043 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
16044 explicitly instantiated class template. */
16047 instantiate_decl (tree d, int defer_ok,
16048 bool expl_inst_class_mem_p)
16050 tree tmpl = DECL_TI_TEMPLATE (d);
16057 bool pattern_defined;
16059 location_t saved_loc = input_location;
16062 /* This function should only be used to instantiate templates for
16063 functions and static member variables. */
16064 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
16065 || TREE_CODE (d) == VAR_DECL);
16067 /* Variables are never deferred; if instantiation is required, they
16068 are instantiated right away. That allows for better code in the
16069 case that an expression refers to the value of the variable --
16070 if the variable has a constant value the referring expression can
16071 take advantage of that fact. */
16072 if (TREE_CODE (d) == VAR_DECL)
16075 /* Don't instantiate cloned functions. Instead, instantiate the
16076 functions they cloned. */
16077 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
16078 d = DECL_CLONED_FUNCTION (d);
16080 if (DECL_TEMPLATE_INSTANTIATED (d)
16081 || DECL_TEMPLATE_SPECIALIZATION (d))
16082 /* D has already been instantiated or explicitly specialized, so
16083 there's nothing for us to do here.
16085 It might seem reasonable to check whether or not D is an explicit
16086 instantiation, and, if so, stop here. But when an explicit
16087 instantiation is deferred until the end of the compilation,
16088 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
16089 the instantiation. */
16092 /* Check to see whether we know that this template will be
16093 instantiated in some other file, as with "extern template"
16095 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
16097 /* In general, we do not instantiate such templates. */
16098 if (external_p && !always_instantiate_p (d))
16101 gen_tmpl = most_general_template (tmpl);
16102 gen_args = DECL_TI_ARGS (d);
16104 if (tmpl != gen_tmpl)
16105 /* We should already have the extra args. */
16106 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
16107 == TMPL_ARGS_DEPTH (gen_args));
16108 /* And what's in the hash table should match D. */
16109 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
16110 || spec == NULL_TREE);
16112 /* This needs to happen before any tsubsting. */
16113 if (! push_tinst_level (d))
16116 timevar_push (TV_PARSE);
16118 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
16119 for the instantiation. */
16120 td = template_for_substitution (d);
16121 code_pattern = DECL_TEMPLATE_RESULT (td);
16123 /* We should never be trying to instantiate a member of a class
16124 template or partial specialization. */
16125 gcc_assert (d != code_pattern);
16127 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
16128 || DECL_TEMPLATE_SPECIALIZATION (td))
16129 /* In the case of a friend template whose definition is provided
16130 outside the class, we may have too many arguments. Drop the
16131 ones we don't need. The same is true for specializations. */
16132 args = get_innermost_template_args
16133 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
16137 if (TREE_CODE (d) == FUNCTION_DECL)
16138 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
16140 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
16142 /* We may be in the middle of deferred access check. Disable it now. */
16143 push_deferring_access_checks (dk_no_deferred);
16145 /* Unless an explicit instantiation directive has already determined
16146 the linkage of D, remember that a definition is available for
16148 if (pattern_defined
16149 && !DECL_INTERFACE_KNOWN (d)
16150 && !DECL_NOT_REALLY_EXTERN (d))
16151 mark_definable (d);
16153 input_location = DECL_SOURCE_LOCATION (d);
16155 /* If D is a member of an explicitly instantiated class template,
16156 and no definition is available, treat it like an implicit
16158 if (!pattern_defined && expl_inst_class_mem_p
16159 && DECL_EXPLICIT_INSTANTIATION (d))
16161 DECL_NOT_REALLY_EXTERN (d) = 0;
16162 DECL_INTERFACE_KNOWN (d) = 0;
16163 SET_DECL_IMPLICIT_INSTANTIATION (d);
16166 /* Recheck the substitutions to obtain any warning messages
16167 about ignoring cv qualifiers. Don't do this for artificial decls,
16168 as it breaks the context-sensitive substitution for lambda op(). */
16169 if (!defer_ok && !DECL_ARTIFICIAL (d))
16171 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
16172 tree type = TREE_TYPE (gen);
16174 /* Make sure that we can see identifiers, and compute access
16175 correctly. D is already the target FUNCTION_DECL with the
16177 push_access_scope (d);
16179 if (TREE_CODE (gen) == FUNCTION_DECL)
16181 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
16182 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
16184 /* Don't simply tsubst the function type, as that will give
16185 duplicate warnings about poor parameter qualifications.
16186 The function arguments are the same as the decl_arguments
16187 without the top level cv qualifiers. */
16188 type = TREE_TYPE (type);
16190 tsubst (type, gen_args, tf_warning_or_error, d);
16192 pop_access_scope (d);
16195 /* Defer all other templates, unless we have been explicitly
16196 forbidden from doing so. */
16197 if (/* If there is no definition, we cannot instantiate the
16200 /* If it's OK to postpone instantiation, do so. */
16202 /* If this is a static data member that will be defined
16203 elsewhere, we don't want to instantiate the entire data
16204 member, but we do want to instantiate the initializer so that
16205 we can substitute that elsewhere. */
16206 || (external_p && TREE_CODE (d) == VAR_DECL))
16208 /* The definition of the static data member is now required so
16209 we must substitute the initializer. */
16210 if (TREE_CODE (d) == VAR_DECL
16211 && !DECL_INITIAL (d)
16212 && DECL_INITIAL (code_pattern))
16217 ns = decl_namespace_context (d);
16218 push_nested_namespace (ns);
16219 push_nested_class (DECL_CONTEXT (d));
16220 init = tsubst_expr (DECL_INITIAL (code_pattern),
16222 tf_warning_or_error, NULL_TREE,
16223 /*integral_constant_expression_p=*/false);
16224 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
16225 /*asmspec_tree=*/NULL_TREE,
16226 LOOKUP_ONLYCONVERTING);
16227 pop_nested_class ();
16228 pop_nested_namespace (ns);
16231 /* We restore the source position here because it's used by
16232 add_pending_template. */
16233 input_location = saved_loc;
16235 if (at_eof && !pattern_defined
16236 && DECL_EXPLICIT_INSTANTIATION (d)
16237 && DECL_NOT_REALLY_EXTERN (d))
16240 The definition of a non-exported function template, a
16241 non-exported member function template, or a non-exported
16242 member function or static data member of a class template
16243 shall be present in every translation unit in which it is
16244 explicitly instantiated. */
16245 permerror (input_location, "explicit instantiation of %qD "
16246 "but no definition available", d);
16248 /* ??? Historically, we have instantiated inline functions, even
16249 when marked as "extern template". */
16250 if (!(external_p && TREE_CODE (d) == VAR_DECL))
16251 add_pending_template (d);
16254 /* Tell the repository that D is available in this translation unit
16255 -- and see if it is supposed to be instantiated here. */
16256 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
16258 /* In a PCH file, despite the fact that the repository hasn't
16259 requested instantiation in the PCH it is still possible that
16260 an instantiation will be required in a file that includes the
16263 add_pending_template (d);
16264 /* Instantiate inline functions so that the inliner can do its
16265 job, even though we'll not be emitting a copy of this
16267 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
16271 need_push = !cfun || !global_bindings_p ();
16273 push_to_top_level ();
16275 /* Mark D as instantiated so that recursive calls to
16276 instantiate_decl do not try to instantiate it again. */
16277 DECL_TEMPLATE_INSTANTIATED (d) = 1;
16279 /* Regenerate the declaration in case the template has been modified
16280 by a subsequent redeclaration. */
16281 regenerate_decl_from_template (d, td);
16283 /* We already set the file and line above. Reset them now in case
16284 they changed as a result of calling regenerate_decl_from_template. */
16285 input_location = DECL_SOURCE_LOCATION (d);
16287 if (TREE_CODE (d) == VAR_DECL)
16291 /* Clear out DECL_RTL; whatever was there before may not be right
16292 since we've reset the type of the declaration. */
16293 SET_DECL_RTL (d, NULL_RTX);
16294 DECL_IN_AGGR_P (d) = 0;
16296 /* The initializer is placed in DECL_INITIAL by
16297 regenerate_decl_from_template. Pull it out so that
16298 cp_finish_decl can process it. */
16299 init = DECL_INITIAL (d);
16300 DECL_INITIAL (d) = NULL_TREE;
16301 DECL_INITIALIZED_P (d) = 0;
16303 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
16304 initializer. That function will defer actual emission until
16305 we have a chance to determine linkage. */
16306 DECL_EXTERNAL (d) = 0;
16308 /* Enter the scope of D so that access-checking works correctly. */
16309 push_nested_class (DECL_CONTEXT (d));
16310 cp_finish_decl (d, init, false, NULL_TREE, 0);
16311 pop_nested_class ();
16313 else if (TREE_CODE (d) == FUNCTION_DECL)
16315 htab_t saved_local_specializations;
16320 /* Save away the current list, in case we are instantiating one
16321 template from within the body of another. */
16322 saved_local_specializations = local_specializations;
16324 /* Set up the list of local specializations. */
16325 local_specializations = htab_create (37,
16326 hash_local_specialization,
16327 eq_local_specializations,
16330 /* Set up context. */
16331 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
16333 /* Create substitution entries for the parameters. */
16334 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
16335 tmpl_parm = DECL_ARGUMENTS (subst_decl);
16336 spec_parm = DECL_ARGUMENTS (d);
16337 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
16339 register_local_specialization (spec_parm, tmpl_parm);
16340 spec_parm = skip_artificial_parms_for (d, spec_parm);
16341 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
16343 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
16345 register_local_specialization (spec_parm, tmpl_parm);
16346 tmpl_parm = TREE_CHAIN (tmpl_parm);
16347 spec_parm = TREE_CHAIN (spec_parm);
16349 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
16351 /* Register the (value) argument pack as a specialization of
16352 TMPL_PARM, then move on. */
16353 tree argpack = make_fnparm_pack (spec_parm);
16354 register_local_specialization (argpack, tmpl_parm);
16355 tmpl_parm = TREE_CHAIN (tmpl_parm);
16356 spec_parm = NULL_TREE;
16358 gcc_assert (!spec_parm);
16360 /* Substitute into the body of the function. */
16361 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
16362 tf_warning_or_error, tmpl,
16363 /*integral_constant_expression_p=*/false);
16365 /* Set the current input_location to the end of the function
16366 so that finish_function knows where we are. */
16367 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
16369 /* We don't need the local specializations any more. */
16370 htab_delete (local_specializations);
16371 local_specializations = saved_local_specializations;
16373 /* Finish the function. */
16374 d = finish_function (0);
16375 expand_or_defer_fn (d);
16378 /* We're not deferring instantiation any more. */
16379 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
16382 pop_from_top_level ();
16385 input_location = saved_loc;
16386 pop_deferring_access_checks ();
16387 pop_tinst_level ();
16389 timevar_pop (TV_PARSE);
16394 /* Run through the list of templates that we wish we could
16395 instantiate, and instantiate any we can. RETRIES is the
16396 number of times we retry pending template instantiation. */
16399 instantiate_pending_templates (int retries)
16402 location_t saved_loc = input_location;
16404 /* Instantiating templates may trigger vtable generation. This in turn
16405 may require further template instantiations. We place a limit here
16406 to avoid infinite loop. */
16407 if (pending_templates && retries >= max_tinst_depth)
16409 tree decl = pending_templates->tinst->decl;
16411 error ("template instantiation depth exceeds maximum of %d"
16412 " instantiating %q+D, possibly from virtual table generation"
16413 " (use -ftemplate-depth-NN to increase the maximum)",
16414 max_tinst_depth, decl);
16415 if (TREE_CODE (decl) == FUNCTION_DECL)
16416 /* Pretend that we defined it. */
16417 DECL_INITIAL (decl) = error_mark_node;
16423 struct pending_template **t = &pending_templates;
16424 struct pending_template *last = NULL;
16428 tree instantiation = reopen_tinst_level ((*t)->tinst);
16429 bool complete = false;
16431 if (TYPE_P (instantiation))
16435 if (!COMPLETE_TYPE_P (instantiation))
16437 instantiate_class_template (instantiation);
16438 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
16439 for (fn = TYPE_METHODS (instantiation);
16441 fn = TREE_CHAIN (fn))
16442 if (! DECL_ARTIFICIAL (fn))
16443 instantiate_decl (fn,
16445 /*expl_inst_class_mem_p=*/false);
16446 if (COMPLETE_TYPE_P (instantiation))
16450 complete = COMPLETE_TYPE_P (instantiation);
16454 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
16455 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
16458 = instantiate_decl (instantiation,
16460 /*expl_inst_class_mem_p=*/false);
16461 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
16465 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
16466 || DECL_TEMPLATE_INSTANTIATED (instantiation));
16470 /* If INSTANTIATION has been instantiated, then we don't
16471 need to consider it again in the future. */
16479 current_tinst_level = NULL;
16481 last_pending_template = last;
16483 while (reconsider);
16485 input_location = saved_loc;
16488 /* Substitute ARGVEC into T, which is a list of initializers for
16489 either base class or a non-static data member. The TREE_PURPOSEs
16490 are DECLs, and the TREE_VALUEs are the initializer values. Used by
16491 instantiate_decl. */
16494 tsubst_initializer_list (tree t, tree argvec)
16496 tree inits = NULL_TREE;
16498 for (; t; t = TREE_CHAIN (t))
16502 tree expanded_bases = NULL_TREE;
16503 tree expanded_arguments = NULL_TREE;
16506 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
16511 /* Expand the base class expansion type into separate base
16513 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
16514 tf_warning_or_error,
16516 if (expanded_bases == error_mark_node)
16519 /* We'll be building separate TREE_LISTs of arguments for
16521 len = TREE_VEC_LENGTH (expanded_bases);
16522 expanded_arguments = make_tree_vec (len);
16523 for (i = 0; i < len; i++)
16524 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
16526 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
16527 expand each argument in the TREE_VALUE of t. */
16528 expr = make_node (EXPR_PACK_EXPANSION);
16529 PACK_EXPANSION_PARAMETER_PACKS (expr) =
16530 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
16532 if (TREE_VALUE (t) == void_type_node)
16533 /* VOID_TYPE_NODE is used to indicate
16534 value-initialization. */
16536 for (i = 0; i < len; i++)
16537 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
16541 /* Substitute parameter packs into each argument in the
16543 in_base_initializer = 1;
16544 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
16546 tree expanded_exprs;
16548 /* Expand the argument. */
16549 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
16551 = tsubst_pack_expansion (expr, argvec,
16552 tf_warning_or_error,
16554 if (expanded_exprs == error_mark_node)
16557 /* Prepend each of the expanded expressions to the
16558 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
16559 for (i = 0; i < len; i++)
16561 TREE_VEC_ELT (expanded_arguments, i) =
16562 tree_cons (NULL_TREE,
16563 TREE_VEC_ELT (expanded_exprs, i),
16564 TREE_VEC_ELT (expanded_arguments, i));
16567 in_base_initializer = 0;
16569 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
16570 since we built them backwards. */
16571 for (i = 0; i < len; i++)
16573 TREE_VEC_ELT (expanded_arguments, i) =
16574 nreverse (TREE_VEC_ELT (expanded_arguments, i));
16579 for (i = 0; i < len; ++i)
16581 if (expanded_bases)
16583 decl = TREE_VEC_ELT (expanded_bases, i);
16584 decl = expand_member_init (decl);
16585 init = TREE_VEC_ELT (expanded_arguments, i);
16589 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
16590 tf_warning_or_error, NULL_TREE);
16592 decl = expand_member_init (decl);
16593 if (decl && !DECL_P (decl))
16594 in_base_initializer = 1;
16596 init = tsubst_expr (TREE_VALUE (t), argvec,
16597 tf_warning_or_error, NULL_TREE,
16598 /*integral_constant_expression_p=*/false);
16599 in_base_initializer = 0;
16604 init = build_tree_list (decl, init);
16605 TREE_CHAIN (init) = inits;
16613 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
16616 set_current_access_from_decl (tree decl)
16618 if (TREE_PRIVATE (decl))
16619 current_access_specifier = access_private_node;
16620 else if (TREE_PROTECTED (decl))
16621 current_access_specifier = access_protected_node;
16623 current_access_specifier = access_public_node;
16626 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
16627 is the instantiation (which should have been created with
16628 start_enum) and ARGS are the template arguments to use. */
16631 tsubst_enum (tree tag, tree newtag, tree args)
16635 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
16640 decl = TREE_VALUE (e);
16641 /* Note that in a template enum, the TREE_VALUE is the
16642 CONST_DECL, not the corresponding INTEGER_CST. */
16643 value = tsubst_expr (DECL_INITIAL (decl),
16644 args, tf_warning_or_error, NULL_TREE,
16645 /*integral_constant_expression_p=*/true);
16647 /* Give this enumeration constant the correct access. */
16648 set_current_access_from_decl (decl);
16650 /* Actually build the enumerator itself. */
16651 build_enumerator (DECL_NAME (decl), value, newtag);
16654 finish_enum (newtag);
16655 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
16656 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
16659 /* DECL is a FUNCTION_DECL that is a template specialization. Return
16660 its type -- but without substituting the innermost set of template
16661 arguments. So, innermost set of template parameters will appear in
16665 get_mostly_instantiated_function_type (tree decl)
16673 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
16674 targs = DECL_TI_ARGS (decl);
16675 tparms = DECL_TEMPLATE_PARMS (tmpl);
16676 parm_depth = TMPL_PARMS_DEPTH (tparms);
16678 /* There should be as many levels of arguments as there are levels
16680 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
16682 fn_type = TREE_TYPE (tmpl);
16684 if (parm_depth == 1)
16685 /* No substitution is necessary. */
16689 int i, save_access_control;
16692 /* Replace the innermost level of the TARGS with NULL_TREEs to
16693 let tsubst know not to substitute for those parameters. */
16694 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
16695 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
16696 SET_TMPL_ARGS_LEVEL (partial_args, i,
16697 TMPL_ARGS_LEVEL (targs, i));
16698 SET_TMPL_ARGS_LEVEL (partial_args,
16699 TMPL_ARGS_DEPTH (targs),
16700 make_tree_vec (DECL_NTPARMS (tmpl)));
16702 /* Disable access control as this function is used only during
16704 save_access_control = flag_access_control;
16705 flag_access_control = 0;
16707 ++processing_template_decl;
16708 /* Now, do the (partial) substitution to figure out the
16709 appropriate function type. */
16710 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
16711 --processing_template_decl;
16713 /* Substitute into the template parameters to obtain the real
16714 innermost set of parameters. This step is important if the
16715 innermost set of template parameters contains value
16716 parameters whose types depend on outer template parameters. */
16717 TREE_VEC_LENGTH (partial_args)--;
16718 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
16720 flag_access_control = save_access_control;
16726 /* Return truthvalue if we're processing a template different from
16727 the last one involved in diagnostics. */
16729 problematic_instantiation_changed (void)
16731 return last_template_error_tick != tinst_level_tick;
16734 /* Remember current template involved in diagnostics. */
16736 record_last_problematic_instantiation (void)
16738 last_template_error_tick = tinst_level_tick;
16741 struct tinst_level *
16742 current_instantiation (void)
16744 return current_tinst_level;
16747 /* [temp.param] Check that template non-type parm TYPE is of an allowable
16748 type. Return zero for ok, nonzero for disallowed. Issue error and
16749 warning messages under control of COMPLAIN. */
16752 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
16754 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
16756 else if (POINTER_TYPE_P (type))
16758 else if (TYPE_PTR_TO_MEMBER_P (type))
16760 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
16762 else if (TREE_CODE (type) == TYPENAME_TYPE)
16765 if (complain & tf_error)
16766 error ("%q#T is not a valid type for a template constant parameter", type);
16770 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
16771 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
16774 dependent_type_p_r (tree type)
16780 A type is dependent if it is:
16782 -- a template parameter. Template template parameters are types
16783 for us (since TYPE_P holds true for them) so we handle
16785 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
16786 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
16788 /* -- a qualified-id with a nested-name-specifier which contains a
16789 class-name that names a dependent type or whose unqualified-id
16790 names a dependent type. */
16791 if (TREE_CODE (type) == TYPENAME_TYPE)
16793 /* -- a cv-qualified type where the cv-unqualified type is
16795 type = TYPE_MAIN_VARIANT (type);
16796 /* -- a compound type constructed from any dependent type. */
16797 if (TYPE_PTR_TO_MEMBER_P (type))
16798 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
16799 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
16801 else if (TREE_CODE (type) == POINTER_TYPE
16802 || TREE_CODE (type) == REFERENCE_TYPE)
16803 return dependent_type_p (TREE_TYPE (type));
16804 else if (TREE_CODE (type) == FUNCTION_TYPE
16805 || TREE_CODE (type) == METHOD_TYPE)
16809 if (dependent_type_p (TREE_TYPE (type)))
16811 for (arg_type = TYPE_ARG_TYPES (type);
16813 arg_type = TREE_CHAIN (arg_type))
16814 if (dependent_type_p (TREE_VALUE (arg_type)))
16818 /* -- an array type constructed from any dependent type or whose
16819 size is specified by a constant expression that is
16820 value-dependent. */
16821 if (TREE_CODE (type) == ARRAY_TYPE)
16823 if (TYPE_DOMAIN (type)
16824 && dependent_type_p (TYPE_DOMAIN (type)))
16826 return dependent_type_p (TREE_TYPE (type));
16828 else if (TREE_CODE (type) == INTEGER_TYPE
16829 && !TREE_CONSTANT (TYPE_MAX_VALUE (type)))
16831 /* If this is the TYPE_DOMAIN of an array type, consider it
16832 dependent. We already checked for value-dependence in
16833 compute_array_index_type. */
16834 return type_dependent_expression_p (TYPE_MAX_VALUE (type));
16837 /* -- a template-id in which either the template name is a template
16839 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
16841 /* ... or any of the template arguments is a dependent type or
16842 an expression that is type-dependent or value-dependent. */
16843 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
16844 && (any_dependent_template_arguments_p
16845 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
16848 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
16849 argument of the `typeof' expression is not type-dependent, then
16850 it should already been have resolved. */
16851 if (TREE_CODE (type) == TYPEOF_TYPE
16852 || TREE_CODE (type) == DECLTYPE_TYPE)
16855 /* A template argument pack is dependent if any of its packed
16857 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
16859 tree args = ARGUMENT_PACK_ARGS (type);
16860 int i, len = TREE_VEC_LENGTH (args);
16861 for (i = 0; i < len; ++i)
16862 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
16866 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
16867 be template parameters. */
16868 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
16871 /* The standard does not specifically mention types that are local
16872 to template functions or local classes, but they should be
16873 considered dependent too. For example:
16875 template <int I> void f() {
16880 The size of `E' cannot be known until the value of `I' has been
16881 determined. Therefore, `E' must be considered dependent. */
16882 scope = TYPE_CONTEXT (type);
16883 if (scope && TYPE_P (scope))
16884 return dependent_type_p (scope);
16885 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
16886 return type_dependent_expression_p (scope);
16888 /* Other types are non-dependent. */
16892 /* Returns TRUE if TYPE is dependent, in the sense of
16893 [temp.dep.type]. */
16896 dependent_type_p (tree type)
16898 /* If there are no template parameters in scope, then there can't be
16899 any dependent types. */
16900 if (!processing_template_decl)
16902 /* If we are not processing a template, then nobody should be
16903 providing us with a dependent type. */
16905 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
16909 /* If the type is NULL, we have not computed a type for the entity
16910 in question; in that case, the type is dependent. */
16914 /* Erroneous types can be considered non-dependent. */
16915 if (type == error_mark_node)
16918 /* If we have not already computed the appropriate value for TYPE,
16920 if (!TYPE_DEPENDENT_P_VALID (type))
16922 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
16923 TYPE_DEPENDENT_P_VALID (type) = 1;
16926 return TYPE_DEPENDENT_P (type);
16929 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
16930 lookup. In other words, a dependent type that is not the current
16934 dependent_scope_p (tree scope)
16936 return (scope && TYPE_P (scope) && dependent_type_p (scope)
16937 && !currently_open_class (scope));
16940 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
16943 dependent_scope_ref_p (tree expression, bool criterion (tree))
16948 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
16950 if (!TYPE_P (TREE_OPERAND (expression, 0)))
16953 scope = TREE_OPERAND (expression, 0);
16954 name = TREE_OPERAND (expression, 1);
16958 An id-expression is type-dependent if it contains a
16959 nested-name-specifier that contains a class-name that names a
16961 /* The suggested resolution to Core Issue 224 implies that if the
16962 qualifying type is the current class, then we must peek
16965 && currently_open_class (scope)
16966 && !criterion (name))
16968 if (dependent_type_p (scope))
16974 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
16975 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
16979 value_dependent_expression_p (tree expression)
16981 if (!processing_template_decl)
16984 /* A name declared with a dependent type. */
16985 if (DECL_P (expression) && type_dependent_expression_p (expression))
16988 switch (TREE_CODE (expression))
16990 case IDENTIFIER_NODE:
16991 /* A name that has not been looked up -- must be dependent. */
16994 case TEMPLATE_PARM_INDEX:
16995 /* A non-type template parm. */
16999 /* A non-type template parm. */
17000 if (DECL_TEMPLATE_PARM_P (expression))
17002 return value_dependent_expression_p (DECL_INITIAL (expression));
17005 /* A constant with integral or enumeration type and is initialized
17006 with an expression that is value-dependent. */
17007 if (DECL_INITIAL (expression)
17008 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
17009 && value_dependent_expression_p (DECL_INITIAL (expression)))
17013 case DYNAMIC_CAST_EXPR:
17014 case STATIC_CAST_EXPR:
17015 case CONST_CAST_EXPR:
17016 case REINTERPRET_CAST_EXPR:
17018 /* These expressions are value-dependent if the type to which
17019 the cast occurs is dependent or the expression being casted
17020 is value-dependent. */
17022 tree type = TREE_TYPE (expression);
17024 if (dependent_type_p (type))
17027 /* A functional cast has a list of operands. */
17028 expression = TREE_OPERAND (expression, 0);
17031 /* If there are no operands, it must be an expression such
17032 as "int()". This should not happen for aggregate types
17033 because it would form non-constant expressions. */
17034 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
17039 if (TREE_CODE (expression) == TREE_LIST)
17040 return any_value_dependent_elements_p (expression);
17042 return value_dependent_expression_p (expression);
17047 /* A `sizeof' expression is value-dependent if the operand is
17048 type-dependent or is a pack expansion. */
17049 expression = TREE_OPERAND (expression, 0);
17050 if (PACK_EXPANSION_P (expression))
17052 else if (TYPE_P (expression))
17053 return dependent_type_p (expression);
17054 return type_dependent_expression_p (expression);
17057 return dependent_scope_ref_p (expression, value_dependent_expression_p);
17059 case COMPONENT_REF:
17060 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
17061 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
17064 /* A CALL_EXPR may appear in a constant expression if it is a
17065 call to a builtin function, e.g., __builtin_constant_p. All
17066 such calls are value-dependent. */
17069 case NONTYPE_ARGUMENT_PACK:
17070 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
17071 is value-dependent. */
17073 tree values = ARGUMENT_PACK_ARGS (expression);
17074 int i, len = TREE_VEC_LENGTH (values);
17076 for (i = 0; i < len; ++i)
17077 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
17085 tree type2 = TRAIT_EXPR_TYPE2 (expression);
17086 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
17087 || (type2 ? dependent_type_p (type2) : false));
17091 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
17092 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
17095 /* A constant expression is value-dependent if any subexpression is
17096 value-dependent. */
17097 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
17099 case tcc_reference:
17101 return (value_dependent_expression_p
17102 (TREE_OPERAND (expression, 0)));
17104 case tcc_comparison:
17106 return ((value_dependent_expression_p
17107 (TREE_OPERAND (expression, 0)))
17108 || (value_dependent_expression_p
17109 (TREE_OPERAND (expression, 1))));
17111 case tcc_expression:
17115 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
17116 /* In some cases, some of the operands may be missing.
17117 (For example, in the case of PREDECREMENT_EXPR, the
17118 amount to increment by may be missing.) That doesn't
17119 make the expression dependent. */
17120 if (TREE_OPERAND (expression, i)
17121 && (value_dependent_expression_p
17122 (TREE_OPERAND (expression, i))))
17132 /* The expression is not value-dependent. */
17136 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
17137 [temp.dep.expr]. */
17140 type_dependent_expression_p (tree expression)
17142 if (!processing_template_decl)
17145 if (expression == error_mark_node)
17148 /* An unresolved name is always dependent. */
17149 if (TREE_CODE (expression) == IDENTIFIER_NODE
17150 || TREE_CODE (expression) == USING_DECL)
17153 /* Some expression forms are never type-dependent. */
17154 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
17155 || TREE_CODE (expression) == SIZEOF_EXPR
17156 || TREE_CODE (expression) == ALIGNOF_EXPR
17157 || TREE_CODE (expression) == TRAIT_EXPR
17158 || TREE_CODE (expression) == TYPEID_EXPR
17159 || TREE_CODE (expression) == DELETE_EXPR
17160 || TREE_CODE (expression) == VEC_DELETE_EXPR
17161 || TREE_CODE (expression) == THROW_EXPR)
17164 /* The types of these expressions depends only on the type to which
17165 the cast occurs. */
17166 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
17167 || TREE_CODE (expression) == STATIC_CAST_EXPR
17168 || TREE_CODE (expression) == CONST_CAST_EXPR
17169 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
17170 || TREE_CODE (expression) == CAST_EXPR)
17171 return dependent_type_p (TREE_TYPE (expression));
17173 /* The types of these expressions depends only on the type created
17174 by the expression. */
17175 if (TREE_CODE (expression) == NEW_EXPR
17176 || TREE_CODE (expression) == VEC_NEW_EXPR)
17178 /* For NEW_EXPR tree nodes created inside a template, either
17179 the object type itself or a TREE_LIST may appear as the
17181 tree type = TREE_OPERAND (expression, 1);
17182 if (TREE_CODE (type) == TREE_LIST)
17183 /* This is an array type. We need to check array dimensions
17185 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
17186 || value_dependent_expression_p
17187 (TREE_OPERAND (TREE_VALUE (type), 1));
17189 return dependent_type_p (type);
17192 if (TREE_CODE (expression) == SCOPE_REF
17193 && dependent_scope_ref_p (expression,
17194 type_dependent_expression_p))
17197 if (TREE_CODE (expression) == FUNCTION_DECL
17198 && DECL_LANG_SPECIFIC (expression)
17199 && DECL_TEMPLATE_INFO (expression)
17200 && (any_dependent_template_arguments_p
17201 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
17204 if (TREE_CODE (expression) == TEMPLATE_DECL
17205 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
17208 if (TREE_CODE (expression) == STMT_EXPR)
17209 expression = stmt_expr_value_expr (expression);
17211 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
17216 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
17218 if (type_dependent_expression_p (elt))
17224 if (TREE_TYPE (expression) == unknown_type_node)
17226 if (TREE_CODE (expression) == ADDR_EXPR)
17227 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
17228 if (TREE_CODE (expression) == COMPONENT_REF
17229 || TREE_CODE (expression) == OFFSET_REF)
17231 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
17233 expression = TREE_OPERAND (expression, 1);
17234 if (TREE_CODE (expression) == IDENTIFIER_NODE)
17237 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
17238 if (TREE_CODE (expression) == SCOPE_REF)
17241 if (TREE_CODE (expression) == BASELINK)
17242 expression = BASELINK_FUNCTIONS (expression);
17244 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
17246 if (any_dependent_template_arguments_p
17247 (TREE_OPERAND (expression, 1)))
17249 expression = TREE_OPERAND (expression, 0);
17251 gcc_assert (TREE_CODE (expression) == OVERLOAD
17252 || TREE_CODE (expression) == FUNCTION_DECL);
17256 if (type_dependent_expression_p (OVL_CURRENT (expression)))
17258 expression = OVL_NEXT (expression);
17263 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
17265 return (dependent_type_p (TREE_TYPE (expression)));
17268 /* Like type_dependent_expression_p, but it also works while not processing
17269 a template definition, i.e. during substitution or mangling. */
17272 type_dependent_expression_p_push (tree expr)
17275 ++processing_template_decl;
17276 b = type_dependent_expression_p (expr);
17277 --processing_template_decl;
17281 /* Returns TRUE if ARGS contains a type-dependent expression. */
17284 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
17289 for (i = 0; VEC_iterate (tree, args, i, arg); ++i)
17291 if (type_dependent_expression_p (arg))
17297 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
17298 expressions) contains any value-dependent expressions. */
17301 any_value_dependent_elements_p (const_tree list)
17303 for (; list; list = TREE_CHAIN (list))
17304 if (value_dependent_expression_p (TREE_VALUE (list)))
17310 /* Returns TRUE if the ARG (a template argument) is dependent. */
17313 dependent_template_arg_p (tree arg)
17315 if (!processing_template_decl)
17318 if (TREE_CODE (arg) == TEMPLATE_DECL
17319 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
17320 return dependent_template_p (arg);
17321 else if (ARGUMENT_PACK_P (arg))
17323 tree args = ARGUMENT_PACK_ARGS (arg);
17324 int i, len = TREE_VEC_LENGTH (args);
17325 for (i = 0; i < len; ++i)
17327 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
17333 else if (TYPE_P (arg))
17334 return dependent_type_p (arg);
17336 return (type_dependent_expression_p (arg)
17337 || value_dependent_expression_p (arg));
17340 /* Returns true if ARGS (a collection of template arguments) contains
17341 any types that require structural equality testing. */
17344 any_template_arguments_need_structural_equality_p (tree args)
17351 if (args == error_mark_node)
17354 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17356 tree level = TMPL_ARGS_LEVEL (args, i + 1);
17357 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17359 tree arg = TREE_VEC_ELT (level, j);
17360 tree packed_args = NULL_TREE;
17363 if (ARGUMENT_PACK_P (arg))
17365 /* Look inside the argument pack. */
17366 packed_args = ARGUMENT_PACK_ARGS (arg);
17367 len = TREE_VEC_LENGTH (packed_args);
17370 for (k = 0; k < len; ++k)
17373 arg = TREE_VEC_ELT (packed_args, k);
17375 if (error_operand_p (arg))
17377 else if (TREE_CODE (arg) == TEMPLATE_DECL
17378 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
17380 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
17382 else if (!TYPE_P (arg) && TREE_TYPE (arg)
17383 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
17392 /* Returns true if ARGS (a collection of template arguments) contains
17393 any dependent arguments. */
17396 any_dependent_template_arguments_p (const_tree args)
17403 if (args == error_mark_node)
17406 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17408 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
17409 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17410 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
17417 /* Returns TRUE if the template TMPL is dependent. */
17420 dependent_template_p (tree tmpl)
17422 if (TREE_CODE (tmpl) == OVERLOAD)
17426 if (dependent_template_p (OVL_FUNCTION (tmpl)))
17428 tmpl = OVL_CHAIN (tmpl);
17433 /* Template template parameters are dependent. */
17434 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
17435 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
17437 /* So are names that have not been looked up. */
17438 if (TREE_CODE (tmpl) == SCOPE_REF
17439 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
17441 /* So are member templates of dependent classes. */
17442 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
17443 return dependent_type_p (DECL_CONTEXT (tmpl));
17447 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
17450 dependent_template_id_p (tree tmpl, tree args)
17452 return (dependent_template_p (tmpl)
17453 || any_dependent_template_arguments_p (args));
17456 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
17460 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
17464 if (!processing_template_decl)
17467 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
17469 tree decl = TREE_VEC_ELT (declv, i);
17470 tree init = TREE_VEC_ELT (initv, i);
17471 tree cond = TREE_VEC_ELT (condv, i);
17472 tree incr = TREE_VEC_ELT (incrv, i);
17474 if (type_dependent_expression_p (decl))
17477 if (init && type_dependent_expression_p (init))
17480 if (type_dependent_expression_p (cond))
17483 if (COMPARISON_CLASS_P (cond)
17484 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
17485 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
17488 if (TREE_CODE (incr) == MODOP_EXPR)
17490 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
17491 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
17494 else if (type_dependent_expression_p (incr))
17496 else if (TREE_CODE (incr) == MODIFY_EXPR)
17498 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
17500 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
17502 tree t = TREE_OPERAND (incr, 1);
17503 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
17504 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
17513 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
17514 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
17515 no such TYPE can be found. Note that this function peers inside
17516 uninstantiated templates and therefore should be used only in
17517 extremely limited situations. ONLY_CURRENT_P restricts this
17518 peering to the currently open classes hierarchy (which is required
17519 when comparing types). */
17522 resolve_typename_type (tree type, bool only_current_p)
17531 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
17533 scope = TYPE_CONTEXT (type);
17534 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
17535 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
17536 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
17537 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
17538 identifier of the TYPENAME_TYPE anymore.
17539 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
17540 TYPENAME_TYPE instead, we avoid messing up with a possible
17541 typedef variant case. */
17542 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
17544 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
17545 it first before we can figure out what NAME refers to. */
17546 if (TREE_CODE (scope) == TYPENAME_TYPE)
17547 scope = resolve_typename_type (scope, only_current_p);
17548 /* If we don't know what SCOPE refers to, then we cannot resolve the
17550 if (TREE_CODE (scope) == TYPENAME_TYPE)
17552 /* If the SCOPE is a template type parameter, we have no way of
17553 resolving the name. */
17554 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
17556 /* If the SCOPE is not the current instantiation, there's no reason
17557 to look inside it. */
17558 if (only_current_p && !currently_open_class (scope))
17560 /* If SCOPE isn't the template itself, it will not have a valid
17561 TYPE_FIELDS list. */
17562 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
17563 /* scope is either the template itself or a compatible instantiation
17564 like X<T>, so look up the name in the original template. */
17565 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
17567 /* scope is a partial instantiation, so we can't do the lookup or we
17568 will lose the template arguments. */
17570 /* Enter the SCOPE so that name lookup will be resolved as if we
17571 were in the class definition. In particular, SCOPE will no
17572 longer be considered a dependent type. */
17573 pushed_scope = push_scope (scope);
17574 /* Look up the declaration. */
17575 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
17577 result = NULL_TREE;
17579 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
17580 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
17583 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
17584 && TREE_CODE (decl) == TYPE_DECL)
17586 result = TREE_TYPE (decl);
17587 if (result == error_mark_node)
17588 result = NULL_TREE;
17590 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
17591 && DECL_CLASS_TEMPLATE_P (decl))
17595 /* Obtain the template and the arguments. */
17596 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
17597 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
17598 /* Instantiate the template. */
17599 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
17600 /*entering_scope=*/0,
17601 tf_error | tf_user);
17602 if (result == error_mark_node)
17603 result = NULL_TREE;
17606 /* Leave the SCOPE. */
17608 pop_scope (pushed_scope);
17610 /* If we failed to resolve it, return the original typename. */
17614 /* If lookup found a typename type, resolve that too. */
17615 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
17617 /* Ill-formed programs can cause infinite recursion here, so we
17618 must catch that. */
17619 TYPENAME_IS_RESOLVING_P (type) = 1;
17620 result = resolve_typename_type (result, only_current_p);
17621 TYPENAME_IS_RESOLVING_P (type) = 0;
17624 /* Qualify the resulting type. */
17625 quals = cp_type_quals (type);
17627 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
17632 /* EXPR is an expression which is not type-dependent. Return a proxy
17633 for EXPR that can be used to compute the types of larger
17634 expressions containing EXPR. */
17637 build_non_dependent_expr (tree expr)
17641 /* Preserve null pointer constants so that the type of things like
17642 "p == 0" where "p" is a pointer can be determined. */
17643 if (null_ptr_cst_p (expr))
17645 /* Preserve OVERLOADs; the functions must be available to resolve
17648 if (TREE_CODE (inner_expr) == STMT_EXPR)
17649 inner_expr = stmt_expr_value_expr (inner_expr);
17650 if (TREE_CODE (inner_expr) == ADDR_EXPR)
17651 inner_expr = TREE_OPERAND (inner_expr, 0);
17652 if (TREE_CODE (inner_expr) == COMPONENT_REF)
17653 inner_expr = TREE_OPERAND (inner_expr, 1);
17654 if (is_overloaded_fn (inner_expr)
17655 || TREE_CODE (inner_expr) == OFFSET_REF)
17657 /* There is no need to return a proxy for a variable. */
17658 if (TREE_CODE (expr) == VAR_DECL)
17660 /* Preserve string constants; conversions from string constants to
17661 "char *" are allowed, even though normally a "const char *"
17662 cannot be used to initialize a "char *". */
17663 if (TREE_CODE (expr) == STRING_CST)
17665 /* Preserve arithmetic constants, as an optimization -- there is no
17666 reason to create a new node. */
17667 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
17669 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
17670 There is at least one place where we want to know that a
17671 particular expression is a throw-expression: when checking a ?:
17672 expression, there are special rules if the second or third
17673 argument is a throw-expression. */
17674 if (TREE_CODE (expr) == THROW_EXPR)
17677 if (TREE_CODE (expr) == COND_EXPR)
17678 return build3 (COND_EXPR,
17680 TREE_OPERAND (expr, 0),
17681 (TREE_OPERAND (expr, 1)
17682 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
17683 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
17684 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
17685 if (TREE_CODE (expr) == COMPOUND_EXPR
17686 && !COMPOUND_EXPR_OVERLOADED (expr))
17687 return build2 (COMPOUND_EXPR,
17689 TREE_OPERAND (expr, 0),
17690 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
17692 /* If the type is unknown, it can't really be non-dependent */
17693 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
17695 /* Otherwise, build a NON_DEPENDENT_EXPR.
17697 REFERENCE_TYPEs are not stripped for expressions in templates
17698 because doing so would play havoc with mangling. Consider, for
17701 template <typename T> void f<T& g>() { g(); }
17703 In the body of "f", the expression for "g" will have
17704 REFERENCE_TYPE, even though the standard says that it should
17705 not. The reason is that we must preserve the syntactic form of
17706 the expression so that mangling (say) "f<g>" inside the body of
17707 "f" works out correctly. Therefore, the REFERENCE_TYPE is
17709 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
17712 /* ARGS is a vector of expressions as arguments to a function call.
17713 Replace the arguments with equivalent non-dependent expressions.
17714 This modifies ARGS in place. */
17717 make_args_non_dependent (VEC(tree,gc) *args)
17722 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
17724 tree newarg = build_non_dependent_expr (arg);
17726 VEC_replace (tree, args, ix, newarg);
17730 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
17731 with a level one deeper than the actual template parms. */
17738 /* ??? Is it worth caching this for multiple autos at the same level? */
17739 au = cxx_make_type (TEMPLATE_TYPE_PARM);
17740 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
17741 TYPE_DECL, get_identifier ("auto"), au);
17742 TYPE_STUB_DECL (au) = TYPE_NAME (au);
17743 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
17744 (0, processing_template_decl + 1, processing_template_decl + 1,
17745 TYPE_NAME (au), NULL_TREE);
17746 TYPE_CANONICAL (au) = canonical_type_parameter (au);
17747 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
17748 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
17753 /* Given type ARG, return std::initializer_list<ARG>. */
17758 tree std_init_list = namespace_binding
17759 (get_identifier ("initializer_list"), std_node);
17761 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
17763 error ("deducing from brace-enclosed initializer list requires "
17764 "#include <initializer_list>");
17765 return error_mark_node;
17767 argvec = make_tree_vec (1);
17768 TREE_VEC_ELT (argvec, 0) = arg;
17769 return lookup_template_class (std_init_list, argvec, NULL_TREE,
17770 NULL_TREE, 0, tf_warning_or_error);
17773 /* Replace auto in TYPE with std::initializer_list<auto>. */
17776 listify_autos (tree type, tree auto_node)
17778 tree init_auto = listify (auto_node);
17779 tree argvec = make_tree_vec (1);
17780 TREE_VEC_ELT (argvec, 0) = init_auto;
17781 if (processing_template_decl)
17782 argvec = add_to_template_args (current_template_args (), argvec);
17783 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
17786 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
17787 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
17790 do_auto_deduction (tree type, tree init, tree auto_node)
17792 tree parms, tparms, targs;
17796 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
17797 with either a new invented type template parameter U or, if the
17798 initializer is a braced-init-list (8.5.4), with
17799 std::initializer_list<U>. */
17800 if (BRACE_ENCLOSED_INITIALIZER_P (init))
17801 type = listify_autos (type, auto_node);
17803 parms = build_tree_list (NULL_TREE, type);
17805 tparms = make_tree_vec (1);
17806 targs = make_tree_vec (1);
17807 TREE_VEC_ELT (tparms, 0)
17808 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
17809 val = type_unification_real (tparms, targs, parms, args, 1, 0,
17810 DEDUCE_CALL, LOOKUP_NORMAL);
17813 error ("unable to deduce %qT from %qE", type, init);
17814 return error_mark_node;
17817 if (processing_template_decl)
17818 targs = add_to_template_args (current_template_args (), targs);
17819 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
17822 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
17826 splice_late_return_type (tree type, tree late_return_type)
17830 if (late_return_type == NULL_TREE)
17832 argvec = make_tree_vec (1);
17833 TREE_VEC_ELT (argvec, 0) = late_return_type;
17834 if (processing_template_decl)
17835 argvec = add_to_template_args (current_template_args (), argvec);
17836 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
17839 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
17842 is_auto (const_tree type)
17844 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
17845 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
17851 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
17852 appear as a type-specifier for the declaration in question, we don't
17853 have to look through the whole type. */
17856 type_uses_auto (tree type)
17858 enum tree_code code;
17859 if (is_auto (type))
17862 code = TREE_CODE (type);
17864 if (code == POINTER_TYPE || code == REFERENCE_TYPE
17865 || code == OFFSET_TYPE || code == FUNCTION_TYPE
17866 || code == METHOD_TYPE || code == ARRAY_TYPE)
17867 return type_uses_auto (TREE_TYPE (type));
17869 if (TYPE_PTRMEMFUNC_P (type))
17870 return type_uses_auto (TREE_TYPE (TREE_TYPE
17871 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
17876 /* For a given template T, return the list of typedefs referenced
17877 in T for which access check is needed at T instantiation time.
17878 T is either a FUNCTION_DECL or a RECORD_TYPE.
17879 Those typedefs were added to T by the function
17880 append_type_to_template_for_access_check. */
17883 get_types_needing_access_check (tree t)
17885 tree ti, result = NULL_TREE;
17887 if (!t || t == error_mark_node)
17890 if (!(ti = get_template_info (t)))
17893 if (CLASS_TYPE_P (t)
17894 || TREE_CODE (t) == FUNCTION_DECL)
17896 if (!TI_TEMPLATE (ti))
17899 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
17905 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
17906 tied to T. That list of typedefs will be access checked at
17907 T instantiation time.
17908 T is either a FUNCTION_DECL or a RECORD_TYPE.
17909 TYPE_DECL is a TYPE_DECL node representing a typedef.
17910 SCOPE is the scope through which TYPE_DECL is accessed.
17912 This function is a subroutine of
17913 append_type_to_template_for_access_check. */
17916 append_type_to_template_for_access_check_1 (tree t,
17922 if (!t || t == error_mark_node)
17925 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
17926 || CLASS_TYPE_P (t))
17928 && TREE_CODE (type_decl) == TYPE_DECL
17931 if (!(ti = get_template_info (t)))
17934 gcc_assert (TI_TEMPLATE (ti));
17936 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti) =
17937 tree_cons (type_decl, scope, TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti));
17940 /* Append TYPE_DECL to the template TEMPL.
17941 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
17942 At TEMPL instanciation time, TYPE_DECL will be checked to see
17943 if it can be accessed through SCOPE.
17945 e.g. consider the following code snippet:
17952 template<class U> struct S
17959 At S<char> instantiation time, we need to check the access of C::myint
17960 In other words, we need to check the access of the myint typedef through
17961 the C scope. For that purpose, this function will add the myint typedef
17962 and the scope C through which its being accessed to a list of typedefs
17963 tied to the template S. That list will be walked at template instantiation
17964 time and access check performed on each typedefs it contains.
17965 Note that this particular code snippet should yield an error because
17966 myint is private to C. */
17969 append_type_to_template_for_access_check (tree templ,
17975 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
17977 /* Make sure we don't append the type to the template twice. */
17978 for (node = get_types_needing_access_check (templ);
17980 node = TREE_CHAIN (node))
17982 tree decl = TREE_PURPOSE (node);
17983 tree type_scope = TREE_VALUE (node);
17985 if (decl == type_decl && type_scope == scope)
17989 append_type_to_template_for_access_check_1 (templ, type_decl, scope);
17992 /* Set up the hash tables for template instantiations. */
17995 init_template_processing (void)
17997 decl_specializations = htab_create_ggc (37,
17998 hash_specialization,
17999 eq_specializations,
18001 type_specializations = htab_create_ggc (37,
18002 hash_specialization,
18003 eq_specializations,
18007 #include "gt-cp-pt.h"