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, 2010, 2011
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"
38 #include "c-family/c-common.h"
39 #include "c-family/c-objc.h"
40 #include "cp-objcp-common.h"
41 #include "tree-inline.h"
46 #include "tree-iterator.h"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work. */
56 struct GTY ((chain_next ("%h.next"))) pending_template {
57 struct pending_template *next;
58 struct tinst_level *tinst;
61 static GTY(()) struct pending_template *pending_templates;
62 static GTY(()) struct pending_template *last_pending_template;
64 int processing_template_parmlist;
65 static int template_header_count;
67 static GTY(()) tree saved_trees;
68 static VEC(int,heap) *inline_parm_levels;
70 static GTY(()) struct tinst_level *current_tinst_level;
72 static GTY(()) tree saved_access_scope;
74 /* Live only within one (recursive) call to tsubst_expr. We use
75 this to pass the statement expression node from the STMT_EXPR
76 to the EXPR_STMT that is its result. */
77 static tree cur_stmt_expr;
79 /* A map from local variable declarations in the body of the template
80 presently being instantiated to the corresponding instantiated
82 static htab_t local_specializations;
84 typedef struct GTY(()) spec_entry
91 static GTY ((param_is (spec_entry)))
92 htab_t decl_specializations;
94 static GTY ((param_is (spec_entry)))
95 htab_t type_specializations;
97 /* Contains canonical template parameter types. The vector is indexed by
98 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
99 TREE_LIST, whose TREE_VALUEs contain the canonical template
100 parameters of various types and levels. */
101 static GTY(()) VEC(tree,gc) *canonical_template_parms;
103 #define UNIFY_ALLOW_NONE 0
104 #define UNIFY_ALLOW_MORE_CV_QUAL 1
105 #define UNIFY_ALLOW_LESS_CV_QUAL 2
106 #define UNIFY_ALLOW_DERIVED 4
107 #define UNIFY_ALLOW_INTEGER 8
108 #define UNIFY_ALLOW_OUTER_LEVEL 16
109 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
110 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
112 enum template_base_result {
114 tbr_ambiguous_baseclass,
118 static void push_access_scope (tree);
119 static void pop_access_scope (tree);
120 static void push_deduction_access_scope (tree);
121 static void pop_deduction_access_scope (tree);
122 static bool resolve_overloaded_unification (tree, tree, tree, tree,
123 unification_kind_t, int,
125 static int try_one_overload (tree, tree, tree, tree, tree,
126 unification_kind_t, int, bool, bool);
127 static int unify (tree, tree, tree, tree, int, bool);
128 static void add_pending_template (tree);
129 static tree reopen_tinst_level (struct tinst_level *);
130 static tree tsubst_initializer_list (tree, tree);
131 static tree get_class_bindings (tree, tree, tree);
132 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
134 static void tsubst_enum (tree, tree, tree);
135 static tree add_to_template_args (tree, tree);
136 static tree add_outermost_template_args (tree, tree);
137 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
138 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
140 static int type_unification_real (tree, tree, tree, const tree *,
141 unsigned int, int, unification_kind_t, int,
143 static void note_template_header (int);
144 static tree convert_nontype_argument_function (tree, tree);
145 static tree convert_nontype_argument (tree, tree, tsubst_flags_t);
146 static tree convert_template_argument (tree, tree, tree,
147 tsubst_flags_t, int, tree);
148 static int for_each_template_parm (tree, tree_fn_t, void*,
149 struct pointer_set_t*, bool);
150 static tree expand_template_argument_pack (tree);
151 static tree build_template_parm_index (int, int, int, int, tree, tree);
152 static bool inline_needs_template_parms (tree);
153 static void push_inline_template_parms_recursive (tree, int);
154 static tree retrieve_local_specialization (tree);
155 static void register_local_specialization (tree, tree);
156 static hashval_t hash_specialization (const void *p);
157 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
158 static int mark_template_parm (tree, void *);
159 static int template_parm_this_level_p (tree, void *);
160 static tree tsubst_friend_function (tree, tree);
161 static tree tsubst_friend_class (tree, tree);
162 static int can_complete_type_without_circularity (tree);
163 static tree get_bindings (tree, tree, tree, bool);
164 static int template_decl_level (tree);
165 static int check_cv_quals_for_unify (int, tree, tree);
166 static void template_parm_level_and_index (tree, int*, int*);
167 static int unify_pack_expansion (tree, tree, tree,
168 tree, unification_kind_t, bool, bool);
169 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
170 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
171 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
172 static void regenerate_decl_from_template (tree, tree);
173 static tree most_specialized_class (tree, tree, tsubst_flags_t);
174 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
175 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
176 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
177 static bool check_specialization_scope (void);
178 static tree process_partial_specialization (tree);
179 static void set_current_access_from_decl (tree);
180 static enum template_base_result get_template_base (tree, tree, tree, tree,
182 static tree try_class_unification (tree, tree, tree, tree, bool);
183 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
185 static bool template_template_parm_bindings_ok_p (tree, tree);
186 static int template_args_equal (tree, tree);
187 static void tsubst_default_arguments (tree);
188 static tree for_each_template_parm_r (tree *, int *, void *);
189 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
190 static void copy_default_args_to_explicit_spec (tree);
191 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
192 static int eq_local_specializations (const void *, const void *);
193 static bool dependent_template_arg_p (tree);
194 static bool any_template_arguments_need_structural_equality_p (tree);
195 static bool dependent_type_p_r (tree);
196 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
197 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
198 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
199 static tree tsubst_decl (tree, tree, tsubst_flags_t);
200 static void perform_typedefs_access_check (tree tmpl, tree targs);
201 static void append_type_to_template_for_access_check_1 (tree, tree, tree,
203 static tree listify (tree);
204 static tree listify_autos (tree, tree);
205 static tree template_parm_to_arg (tree t);
206 static bool arg_from_parm_pack_p (tree, tree);
207 static tree current_template_args (void);
208 static tree fixup_template_type_parm_type (tree, int);
209 static tree fixup_template_parm_index (tree, tree, int);
210 static tree tsubst_template_parm (tree, tree, tsubst_flags_t);
212 /* Make the current scope suitable for access checking when we are
213 processing T. T can be FUNCTION_DECL for instantiated function
214 template, or VAR_DECL for static member variable (need by
215 instantiate_decl). */
218 push_access_scope (tree t)
220 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
221 || TREE_CODE (t) == VAR_DECL);
223 if (DECL_FRIEND_CONTEXT (t))
224 push_nested_class (DECL_FRIEND_CONTEXT (t));
225 else if (DECL_CLASS_SCOPE_P (t))
226 push_nested_class (DECL_CONTEXT (t));
228 push_to_top_level ();
230 if (TREE_CODE (t) == FUNCTION_DECL)
232 saved_access_scope = tree_cons
233 (NULL_TREE, current_function_decl, saved_access_scope);
234 current_function_decl = t;
238 /* Restore the scope set up by push_access_scope. T is the node we
242 pop_access_scope (tree t)
244 if (TREE_CODE (t) == FUNCTION_DECL)
246 current_function_decl = TREE_VALUE (saved_access_scope);
247 saved_access_scope = TREE_CHAIN (saved_access_scope);
250 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
253 pop_from_top_level ();
256 /* Do any processing required when DECL (a member template
257 declaration) is finished. Returns the TEMPLATE_DECL corresponding
258 to DECL, unless it is a specialization, in which case the DECL
259 itself is returned. */
262 finish_member_template_decl (tree decl)
264 if (decl == error_mark_node)
265 return error_mark_node;
267 gcc_assert (DECL_P (decl));
269 if (TREE_CODE (decl) == TYPE_DECL)
273 type = TREE_TYPE (decl);
274 if (type == error_mark_node)
275 return error_mark_node;
276 if (MAYBE_CLASS_TYPE_P (type)
277 && CLASSTYPE_TEMPLATE_INFO (type)
278 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
280 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
281 check_member_template (tmpl);
286 else if (TREE_CODE (decl) == FIELD_DECL)
287 error ("data member %qD cannot be a member template", decl);
288 else if (DECL_TEMPLATE_INFO (decl))
290 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
292 check_member_template (DECL_TI_TEMPLATE (decl));
293 return DECL_TI_TEMPLATE (decl);
299 error ("invalid member template declaration %qD", decl);
301 return error_mark_node;
304 /* Create a template info node. */
307 build_template_info (tree template_decl, tree template_args)
309 tree result = make_node (TEMPLATE_INFO);
310 TI_TEMPLATE (result) = template_decl;
311 TI_ARGS (result) = template_args;
315 /* Return the template info node corresponding to T, whatever T is. */
318 get_template_info (const_tree t)
320 tree tinfo = NULL_TREE;
322 if (!t || t == error_mark_node)
325 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
326 tinfo = DECL_TEMPLATE_INFO (t);
328 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
331 if (TAGGED_TYPE_P (t))
332 tinfo = TYPE_TEMPLATE_INFO (t);
333 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
334 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t);
339 /* Returns the template nesting level of the indicated class TYPE.
349 A<T>::B<U> has depth two, while A<T> has depth one.
350 Both A<T>::B<int> and A<int>::B<U> have depth one, if
351 they are instantiations, not specializations.
353 This function is guaranteed to return 0 if passed NULL_TREE so
354 that, for example, `template_class_depth (current_class_type)' is
358 template_class_depth (tree type)
363 type && TREE_CODE (type) != NAMESPACE_DECL;
364 type = (TREE_CODE (type) == FUNCTION_DECL)
365 ? CP_DECL_CONTEXT (type) : CP_TYPE_CONTEXT (type))
367 tree tinfo = get_template_info (type);
369 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
370 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
377 /* Subroutine of maybe_begin_member_template_processing.
378 Returns true if processing DECL needs us to push template parms. */
381 inline_needs_template_parms (tree decl)
383 if (! DECL_TEMPLATE_INFO (decl))
386 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
387 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
390 /* Subroutine of maybe_begin_member_template_processing.
391 Push the template parms in PARMS, starting from LEVELS steps into the
392 chain, and ending at the beginning, since template parms are listed
396 push_inline_template_parms_recursive (tree parmlist, int levels)
398 tree parms = TREE_VALUE (parmlist);
402 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
404 ++processing_template_decl;
405 current_template_parms
406 = tree_cons (size_int (processing_template_decl),
407 parms, current_template_parms);
408 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
410 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
412 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
414 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
416 if (parm == error_mark_node)
419 gcc_assert (DECL_P (parm));
421 switch (TREE_CODE (parm))
430 /* Make a CONST_DECL as is done in process_template_parm.
431 It is ugly that we recreate this here; the original
432 version built in process_template_parm is no longer
434 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
435 CONST_DECL, DECL_NAME (parm),
437 DECL_ARTIFICIAL (decl) = 1;
438 TREE_CONSTANT (decl) = 1;
439 TREE_READONLY (decl) = 1;
440 DECL_INITIAL (decl) = DECL_INITIAL (parm);
441 SET_DECL_TEMPLATE_PARM_P (decl);
452 /* Restore the template parameter context for a member template or
453 a friend template defined in a class definition. */
456 maybe_begin_member_template_processing (tree decl)
461 if (inline_needs_template_parms (decl))
463 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
464 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
466 if (DECL_TEMPLATE_SPECIALIZATION (decl))
469 parms = TREE_CHAIN (parms);
472 push_inline_template_parms_recursive (parms, levels);
475 /* Remember how many levels of template parameters we pushed so that
476 we can pop them later. */
477 VEC_safe_push (int, heap, inline_parm_levels, levels);
480 /* Undo the effects of maybe_begin_member_template_processing. */
483 maybe_end_member_template_processing (void)
488 if (VEC_length (int, inline_parm_levels) == 0)
491 last = VEC_pop (int, inline_parm_levels);
492 for (i = 0; i < last; ++i)
494 --processing_template_decl;
495 current_template_parms = TREE_CHAIN (current_template_parms);
500 /* Return a new template argument vector which contains all of ARGS,
501 but has as its innermost set of arguments the EXTRA_ARGS. */
504 add_to_template_args (tree args, tree extra_args)
511 if (args == NULL_TREE || extra_args == error_mark_node)
514 extra_depth = TMPL_ARGS_DEPTH (extra_args);
515 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
517 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
518 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
520 for (j = 1; j <= extra_depth; ++j, ++i)
521 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
526 /* Like add_to_template_args, but only the outermost ARGS are added to
527 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
528 (EXTRA_ARGS) levels are added. This function is used to combine
529 the template arguments from a partial instantiation with the
530 template arguments used to attain the full instantiation from the
531 partial instantiation. */
534 add_outermost_template_args (tree args, tree extra_args)
538 /* If there are more levels of EXTRA_ARGS than there are ARGS,
539 something very fishy is going on. */
540 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
542 /* If *all* the new arguments will be the EXTRA_ARGS, just return
544 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
547 /* For the moment, we make ARGS look like it contains fewer levels. */
548 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
550 new_args = add_to_template_args (args, extra_args);
552 /* Now, we restore ARGS to its full dimensions. */
553 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
558 /* Return the N levels of innermost template arguments from the ARGS. */
561 get_innermost_template_args (tree args, int n)
569 /* If N is 1, just return the innermost set of template arguments. */
571 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
573 /* If we're not removing anything, just return the arguments we were
575 extra_levels = TMPL_ARGS_DEPTH (args) - n;
576 gcc_assert (extra_levels >= 0);
577 if (extra_levels == 0)
580 /* Make a new set of arguments, not containing the outer arguments. */
581 new_args = make_tree_vec (n);
582 for (i = 1; i <= n; ++i)
583 SET_TMPL_ARGS_LEVEL (new_args, i,
584 TMPL_ARGS_LEVEL (args, i + extra_levels));
589 /* The inverse of get_innermost_template_args: Return all but the innermost
590 EXTRA_LEVELS levels of template arguments from the ARGS. */
593 strip_innermost_template_args (tree args, int extra_levels)
596 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
601 /* If N is 1, just return the outermost set of template arguments. */
603 return TMPL_ARGS_LEVEL (args, 1);
605 /* If we're not removing anything, just return the arguments we were
607 gcc_assert (extra_levels >= 0);
608 if (extra_levels == 0)
611 /* Make a new set of arguments, not containing the inner arguments. */
612 new_args = make_tree_vec (n);
613 for (i = 1; i <= n; ++i)
614 SET_TMPL_ARGS_LEVEL (new_args, i,
615 TMPL_ARGS_LEVEL (args, i));
620 /* We've got a template header coming up; push to a new level for storing
624 begin_template_parm_list (void)
626 /* We use a non-tag-transparent scope here, which causes pushtag to
627 put tags in this scope, rather than in the enclosing class or
628 namespace scope. This is the right thing, since we want
629 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
630 global template class, push_template_decl handles putting the
631 TEMPLATE_DECL into top-level scope. For a nested template class,
634 template <class T> struct S1 {
635 template <class T> struct S2 {};
638 pushtag contains special code to call pushdecl_with_scope on the
639 TEMPLATE_DECL for S2. */
640 begin_scope (sk_template_parms, NULL);
641 ++processing_template_decl;
642 ++processing_template_parmlist;
643 note_template_header (0);
646 /* This routine is called when a specialization is declared. If it is
647 invalid to declare a specialization here, an error is reported and
648 false is returned, otherwise this routine will return true. */
651 check_specialization_scope (void)
653 tree scope = current_scope ();
657 An explicit specialization shall be declared in the namespace of
658 which the template is a member, or, for member templates, in the
659 namespace of which the enclosing class or enclosing class
660 template is a member. An explicit specialization of a member
661 function, member class or static data member of a class template
662 shall be declared in the namespace of which the class template
664 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
666 error ("explicit specialization in non-namespace scope %qD", scope);
672 In an explicit specialization declaration for a member of a class
673 template or a member template that appears in namespace scope,
674 the member template and some of its enclosing class templates may
675 remain unspecialized, except that the declaration shall not
676 explicitly specialize a class member template if its enclosing
677 class templates are not explicitly specialized as well. */
678 if (current_template_parms)
680 error ("enclosing class templates are not explicitly specialized");
687 /* We've just seen template <>. */
690 begin_specialization (void)
692 begin_scope (sk_template_spec, NULL);
693 note_template_header (1);
694 return check_specialization_scope ();
697 /* Called at then end of processing a declaration preceded by
701 end_specialization (void)
704 reset_specialization ();
707 /* Any template <>'s that we have seen thus far are not referring to a
708 function specialization. */
711 reset_specialization (void)
713 processing_specialization = 0;
714 template_header_count = 0;
717 /* We've just seen a template header. If SPECIALIZATION is nonzero,
718 it was of the form template <>. */
721 note_template_header (int specialization)
723 processing_specialization = specialization;
724 template_header_count++;
727 /* We're beginning an explicit instantiation. */
730 begin_explicit_instantiation (void)
732 gcc_assert (!processing_explicit_instantiation);
733 processing_explicit_instantiation = true;
738 end_explicit_instantiation (void)
740 gcc_assert (processing_explicit_instantiation);
741 processing_explicit_instantiation = false;
744 /* An explicit specialization or partial specialization TMPL is being
745 declared. Check that the namespace in which the specialization is
746 occurring is permissible. Returns false iff it is invalid to
747 specialize TMPL in the current namespace. */
750 check_specialization_namespace (tree tmpl)
752 tree tpl_ns = decl_namespace_context (tmpl);
756 An explicit specialization shall be declared in the namespace of
757 which the template is a member, or, for member templates, in the
758 namespace of which the enclosing class or enclosing class
759 template is a member. An explicit specialization of a member
760 function, member class or static data member of a class template
761 shall be declared in the namespace of which the class template is
763 if (current_scope() != DECL_CONTEXT (tmpl)
764 && !at_namespace_scope_p ())
766 error ("specialization of %qD must appear at namespace scope", tmpl);
769 if (is_associated_namespace (current_namespace, tpl_ns))
770 /* Same or super-using namespace. */
774 permerror (input_location, "specialization of %qD in different namespace", tmpl);
775 permerror (input_location, " from definition of %q+#D", tmpl);
780 /* SPEC is an explicit instantiation. Check that it is valid to
781 perform this explicit instantiation in the current namespace. */
784 check_explicit_instantiation_namespace (tree spec)
788 /* DR 275: An explicit instantiation shall appear in an enclosing
789 namespace of its template. */
790 ns = decl_namespace_context (spec);
791 if (!is_ancestor (current_namespace, ns))
792 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
793 "(which does not enclose namespace %qD)",
794 spec, current_namespace, ns);
797 /* The TYPE is being declared. If it is a template type, that means it
798 is a partial specialization. Do appropriate error-checking. */
801 maybe_process_partial_specialization (tree type)
805 if (type == error_mark_node)
806 return error_mark_node;
808 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
810 error ("name of class shadows template template parameter %qD",
812 return error_mark_node;
815 context = TYPE_CONTEXT (type);
817 if ((CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
818 /* Consider non-class instantiations of alias templates as
821 && TYPE_TEMPLATE_INFO (type)
822 && DECL_LANG_SPECIFIC (TYPE_NAME (type))
823 && DECL_USE_TEMPLATE (TYPE_NAME (type))))
825 /* This is for ordinary explicit specialization and partial
826 specialization of a template class such as:
828 template <> class C<int>;
832 template <class T> class C<T*>;
834 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
836 if (CLASS_TYPE_P (type)
837 && CLASSTYPE_IMPLICIT_INSTANTIATION (type)
838 && !COMPLETE_TYPE_P (type))
840 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
841 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
842 if (processing_template_decl)
844 if (push_template_decl (TYPE_MAIN_DECL (type))
846 return error_mark_node;
849 else if (CLASS_TYPE_P (type)
850 && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
851 error ("specialization of %qT after instantiation", type);
853 if (DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (type)))
855 error ("partial specialization of alias template %qD",
856 TYPE_TI_TEMPLATE (type));
857 return error_mark_node;
860 else if (CLASS_TYPE_P (type)
861 && !CLASSTYPE_USE_TEMPLATE (type)
862 && CLASSTYPE_TEMPLATE_INFO (type)
863 && context && CLASS_TYPE_P (context)
864 && CLASSTYPE_TEMPLATE_INFO (context))
866 /* This is for an explicit specialization of member class
867 template according to [temp.expl.spec/18]:
869 template <> template <class U> class C<int>::D;
871 The context `C<int>' must be an implicit instantiation.
872 Otherwise this is just a member class template declared
875 template <> class C<int> { template <class U> class D; };
876 template <> template <class U> class C<int>::D;
878 In the first case, `C<int>::D' is a specialization of `C<T>::D'
879 while in the second case, `C<int>::D' is a primary template
880 and `C<T>::D' may not exist. */
882 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
883 && !COMPLETE_TYPE_P (type))
886 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
888 if (current_namespace
889 != decl_namespace_context (tmpl))
891 permerror (input_location, "specializing %q#T in different namespace", type);
892 permerror (input_location, " from definition of %q+#D", tmpl);
895 /* Check for invalid specialization after instantiation:
897 template <> template <> class C<int>::D<int>;
898 template <> template <class U> class C<int>::D; */
900 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
901 t; t = TREE_CHAIN (t))
903 tree inst = TREE_VALUE (t);
904 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
906 /* We already have a full specialization of this partial
907 instantiation. Reassign it to the new member
908 specialization template. */
913 elt.tmpl = most_general_template (tmpl);
914 elt.args = CLASSTYPE_TI_ARGS (inst);
917 htab_remove_elt (type_specializations, &elt);
920 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
922 slot = htab_find_slot (type_specializations, &elt, INSERT);
923 entry = ggc_alloc_spec_entry ();
927 else if (COMPLETE_OR_OPEN_TYPE_P (inst))
928 /* But if we've had an implicit instantiation, that's a
929 problem ([temp.expl.spec]/6). */
930 error ("specialization %qT after instantiation %qT",
934 /* Mark TYPE as a specialization. And as a result, we only
935 have one level of template argument for the innermost
937 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
938 CLASSTYPE_TI_ARGS (type)
939 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
942 else if (processing_specialization)
944 /* Someday C++0x may allow for enum template specialization. */
945 if (cxx_dialect > cxx98 && TREE_CODE (type) == ENUMERAL_TYPE
946 && CLASS_TYPE_P (context) && CLASSTYPE_USE_TEMPLATE (context))
947 pedwarn (input_location, OPT_pedantic, "template specialization "
948 "of %qD not allowed by ISO C++", type);
951 error ("explicit specialization of non-template %qT", type);
952 return error_mark_node;
959 /* Returns nonzero if we can optimize the retrieval of specializations
960 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
961 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
964 optimize_specialization_lookup_p (tree tmpl)
966 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
967 && DECL_CLASS_SCOPE_P (tmpl)
968 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
970 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
971 /* The optimized lookup depends on the fact that the
972 template arguments for the member function template apply
973 purely to the containing class, which is not true if the
974 containing class is an explicit or partial
976 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
977 && !DECL_MEMBER_TEMPLATE_P (tmpl)
978 && !DECL_CONV_FN_P (tmpl)
979 /* It is possible to have a template that is not a member
980 template and is not a member of a template class:
982 template <typename T>
983 struct S { friend A::f(); };
985 Here, the friend function is a template, but the context does
986 not have template information. The optimized lookup relies
987 on having ARGS be the template arguments for both the class
988 and the function template. */
989 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
992 /* Retrieve the specialization (in the sense of [temp.spec] - a
993 specialization is either an instantiation or an explicit
994 specialization) of TMPL for the given template ARGS. If there is
995 no such specialization, return NULL_TREE. The ARGS are a vector of
996 arguments, or a vector of vectors of arguments, in the case of
997 templates with more than one level of parameters.
999 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
1000 then we search for a partial specialization matching ARGS. This
1001 parameter is ignored if TMPL is not a class template. */
1004 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
1006 if (args == error_mark_node)
1009 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1011 /* There should be as many levels of arguments as there are
1012 levels of parameters. */
1013 gcc_assert (TMPL_ARGS_DEPTH (args)
1014 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
1016 if (optimize_specialization_lookup_p (tmpl))
1018 tree class_template;
1019 tree class_specialization;
1020 VEC(tree,gc) *methods;
1024 /* The template arguments actually apply to the containing
1025 class. Find the class specialization with those
1027 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
1028 class_specialization
1029 = retrieve_specialization (class_template, args, 0);
1030 if (!class_specialization)
1032 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
1033 for the specialization. */
1034 idx = class_method_index_for_fn (class_specialization, tmpl);
1037 /* Iterate through the methods with the indicated name, looking
1038 for the one that has an instance of TMPL. */
1039 methods = CLASSTYPE_METHOD_VEC (class_specialization);
1040 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
1042 tree fn = OVL_CURRENT (fns);
1043 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
1044 /* using-declarations can add base methods to the method vec,
1045 and we don't want those here. */
1046 && DECL_CONTEXT (fn) == class_specialization)
1055 htab_t specializations;
1059 elt.spec = NULL_TREE;
1061 if (DECL_CLASS_TEMPLATE_P (tmpl))
1062 specializations = type_specializations;
1064 specializations = decl_specializations;
1067 hash = hash_specialization (&elt);
1068 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1076 /* Like retrieve_specialization, but for local declarations. */
1079 retrieve_local_specialization (tree tmpl)
1083 if (local_specializations == NULL)
1086 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1087 htab_hash_pointer (tmpl));
1088 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1091 /* Returns nonzero iff DECL is a specialization of TMPL. */
1094 is_specialization_of (tree decl, tree tmpl)
1098 if (TREE_CODE (decl) == FUNCTION_DECL)
1102 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1108 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1110 for (t = TREE_TYPE (decl);
1112 t = CLASSTYPE_USE_TEMPLATE (t)
1113 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1114 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1121 /* Returns nonzero iff DECL is a specialization of friend declaration
1122 FRIEND_DECL according to [temp.friend]. */
1125 is_specialization_of_friend (tree decl, tree friend_decl)
1127 bool need_template = true;
1130 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1131 || TREE_CODE (decl) == TYPE_DECL);
1133 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1134 of a template class, we want to check if DECL is a specialization
1136 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1137 && DECL_TEMPLATE_INFO (friend_decl)
1138 && !DECL_USE_TEMPLATE (friend_decl))
1140 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1141 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1142 need_template = false;
1144 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1145 && !PRIMARY_TEMPLATE_P (friend_decl))
1146 need_template = false;
1148 /* There is nothing to do if this is not a template friend. */
1149 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1152 if (is_specialization_of (decl, friend_decl))
1156 A member of a class template may be declared to be a friend of a
1157 non-template class. In this case, the corresponding member of
1158 every specialization of the class template is a friend of the
1159 class granting friendship.
1161 For example, given a template friend declaration
1163 template <class T> friend void A<T>::f();
1165 the member function below is considered a friend
1167 template <> struct A<int> {
1171 For this type of template friend, TEMPLATE_DEPTH below will be
1172 nonzero. To determine if DECL is a friend of FRIEND, we first
1173 check if the enclosing class is a specialization of another. */
1175 template_depth = template_class_depth (CP_DECL_CONTEXT (friend_decl));
1177 && DECL_CLASS_SCOPE_P (decl)
1178 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1179 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1181 /* Next, we check the members themselves. In order to handle
1182 a few tricky cases, such as when FRIEND_DECL's are
1184 template <class T> friend void A<T>::g(T t);
1185 template <class T> template <T t> friend void A<T>::h();
1189 void A<int>::g(int);
1190 template <int> void A<int>::h();
1192 we need to figure out ARGS, the template arguments from
1193 the context of DECL. This is required for template substitution
1194 of `T' in the function parameter of `g' and template parameter
1195 of `h' in the above examples. Here ARGS corresponds to `int'. */
1197 tree context = DECL_CONTEXT (decl);
1198 tree args = NULL_TREE;
1199 int current_depth = 0;
1201 while (current_depth < template_depth)
1203 if (CLASSTYPE_TEMPLATE_INFO (context))
1205 if (current_depth == 0)
1206 args = TYPE_TI_ARGS (context);
1208 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1211 context = TYPE_CONTEXT (context);
1214 if (TREE_CODE (decl) == FUNCTION_DECL)
1219 tree friend_args_type;
1220 tree decl_args_type;
1222 /* Make sure that both DECL and FRIEND_DECL are templates or
1224 is_template = DECL_TEMPLATE_INFO (decl)
1225 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1226 if (need_template ^ is_template)
1228 else if (is_template)
1230 /* If both are templates, check template parameter list. */
1232 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1234 if (!comp_template_parms
1235 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1239 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1242 decl_type = TREE_TYPE (decl);
1244 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1245 tf_none, NULL_TREE);
1246 if (friend_type == error_mark_node)
1249 /* Check if return types match. */
1250 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1253 /* Check if function parameter types match, ignoring the
1254 `this' parameter. */
1255 friend_args_type = TYPE_ARG_TYPES (friend_type);
1256 decl_args_type = TYPE_ARG_TYPES (decl_type);
1257 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1258 friend_args_type = TREE_CHAIN (friend_args_type);
1259 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1260 decl_args_type = TREE_CHAIN (decl_args_type);
1262 return compparms (decl_args_type, friend_args_type);
1266 /* DECL is a TYPE_DECL */
1268 tree decl_type = TREE_TYPE (decl);
1270 /* Make sure that both DECL and FRIEND_DECL are templates or
1273 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1274 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1276 if (need_template ^ is_template)
1278 else if (is_template)
1281 /* If both are templates, check the name of the two
1282 TEMPLATE_DECL's first because is_friend didn't. */
1283 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1284 != DECL_NAME (friend_decl))
1287 /* Now check template parameter list. */
1289 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1291 return comp_template_parms
1292 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1296 return (DECL_NAME (decl)
1297 == DECL_NAME (friend_decl));
1303 /* Register the specialization SPEC as a specialization of TMPL with
1304 the indicated ARGS. IS_FRIEND indicates whether the specialization
1305 is actually just a friend declaration. Returns SPEC, or an
1306 equivalent prior declaration, if available. */
1309 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1316 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1318 if (TREE_CODE (spec) == FUNCTION_DECL
1319 && uses_template_parms (DECL_TI_ARGS (spec)))
1320 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1321 register it; we want the corresponding TEMPLATE_DECL instead.
1322 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1323 the more obvious `uses_template_parms (spec)' to avoid problems
1324 with default function arguments. In particular, given
1325 something like this:
1327 template <class T> void f(T t1, T t = T())
1329 the default argument expression is not substituted for in an
1330 instantiation unless and until it is actually needed. */
1333 if (optimize_specialization_lookup_p (tmpl))
1334 /* We don't put these specializations in the hash table, but we might
1335 want to give an error about a mismatch. */
1336 fn = retrieve_specialization (tmpl, args, 0);
1344 hash = hash_specialization (&elt);
1347 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1349 fn = ((spec_entry *) *slot)->spec;
1354 /* We can sometimes try to re-register a specialization that we've
1355 already got. In particular, regenerate_decl_from_template calls
1356 duplicate_decls which will update the specialization list. But,
1357 we'll still get called again here anyhow. It's more convenient
1358 to simply allow this than to try to prevent it. */
1361 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1363 if (DECL_TEMPLATE_INSTANTIATION (fn))
1365 if (DECL_ODR_USED (fn)
1366 || DECL_EXPLICIT_INSTANTIATION (fn))
1368 error ("specialization of %qD after instantiation",
1370 return error_mark_node;
1375 /* This situation should occur only if the first
1376 specialization is an implicit instantiation, the
1377 second is an explicit specialization, and the
1378 implicit instantiation has not yet been used. That
1379 situation can occur if we have implicitly
1380 instantiated a member function and then specialized
1383 We can also wind up here if a friend declaration that
1384 looked like an instantiation turns out to be a
1387 template <class T> void foo(T);
1388 class S { friend void foo<>(int) };
1389 template <> void foo(int);
1391 We transform the existing DECL in place so that any
1392 pointers to it become pointers to the updated
1395 If there was a definition for the template, but not
1396 for the specialization, we want this to look as if
1397 there were no definition, and vice versa. */
1398 DECL_INITIAL (fn) = NULL_TREE;
1399 duplicate_decls (spec, fn, is_friend);
1400 /* The call to duplicate_decls will have applied
1403 An explicit specialization of a function template
1404 is inline only if it is explicitly declared to be,
1405 and independently of whether its function template
1408 to the primary function; now copy the inline bits to
1409 the various clones. */
1410 FOR_EACH_CLONE (clone, fn)
1412 DECL_DECLARED_INLINE_P (clone)
1413 = DECL_DECLARED_INLINE_P (fn);
1414 DECL_SOURCE_LOCATION (clone)
1415 = DECL_SOURCE_LOCATION (fn);
1417 check_specialization_namespace (fn);
1422 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1424 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1425 /* Dup decl failed, but this is a new definition. Set the
1426 line number so any errors match this new
1428 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1434 return duplicate_decls (spec, fn, is_friend);
1436 /* A specialization must be declared in the same namespace as the
1437 template it is specializing. */
1438 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1439 && !check_specialization_namespace (tmpl))
1440 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1442 if (slot != NULL /* !optimize_specialization_lookup_p (tmpl) */)
1444 spec_entry *entry = ggc_alloc_spec_entry ();
1445 gcc_assert (tmpl && args && spec);
1448 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1449 && PRIMARY_TEMPLATE_P (tmpl)
1450 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1451 /* TMPL is a forward declaration of a template function; keep a list
1452 of all specializations in case we need to reassign them to a friend
1453 template later in tsubst_friend_function. */
1454 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1455 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1461 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1462 TMPL and ARGS members, ignores SPEC. */
1465 eq_specializations (const void *p1, const void *p2)
1467 const spec_entry *e1 = (const spec_entry *)p1;
1468 const spec_entry *e2 = (const spec_entry *)p2;
1470 return (e1->tmpl == e2->tmpl
1471 && comp_template_args (e1->args, e2->args));
1474 /* Returns a hash for a template TMPL and template arguments ARGS. */
1477 hash_tmpl_and_args (tree tmpl, tree args)
1479 hashval_t val = DECL_UID (tmpl);
1480 return iterative_hash_template_arg (args, val);
1483 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1487 hash_specialization (const void *p)
1489 const spec_entry *e = (const spec_entry *)p;
1490 return hash_tmpl_and_args (e->tmpl, e->args);
1493 /* Recursively calculate a hash value for a template argument ARG, for use
1494 in the hash tables of template specializations. */
1497 iterative_hash_template_arg (tree arg, hashval_t val)
1499 unsigned HOST_WIDE_INT i;
1500 enum tree_code code;
1503 if (arg == NULL_TREE)
1504 return iterative_hash_object (arg, val);
1509 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
1510 /* We can get one of these when re-hashing a previous entry in the middle
1511 of substituting into a pack expansion. Just look through it. */
1512 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1514 code = TREE_CODE (arg);
1515 tclass = TREE_CODE_CLASS (code);
1517 val = iterative_hash_object (code, val);
1524 case IDENTIFIER_NODE:
1525 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1529 int i, len = TREE_VEC_LENGTH (arg);
1530 for (i = 0; i < len; ++i)
1531 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1535 case TYPE_PACK_EXPANSION:
1536 case EXPR_PACK_EXPANSION:
1537 val = iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1538 return iterative_hash_template_arg (PACK_EXPANSION_EXTRA_ARGS (arg), val);
1540 case TYPE_ARGUMENT_PACK:
1541 case NONTYPE_ARGUMENT_PACK:
1542 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1545 for (; arg; arg = TREE_CHAIN (arg))
1546 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1550 for (; arg; arg = OVL_NEXT (arg))
1551 val = iterative_hash_template_arg (OVL_CURRENT (arg), val);
1557 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1559 val = iterative_hash_template_arg (field, val);
1560 val = iterative_hash_template_arg (value, val);
1566 if (!DECL_ARTIFICIAL (arg))
1568 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1569 val = iterative_hash_object (DECL_PARM_LEVEL (arg), val);
1571 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1574 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1577 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1578 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1580 case TEMPLATE_PARM_INDEX:
1581 val = iterative_hash_template_arg
1582 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1583 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1584 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1587 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1588 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1589 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1592 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1594 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1598 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1599 code = TREE_CODE (TREE_OPERAND (arg, 1));
1600 val = iterative_hash_object (code, val);
1601 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1604 /* A lambda can't appear in a template arg, but don't crash on
1606 gcc_assert (seen_error ());
1610 case IMPLICIT_CONV_EXPR:
1611 case STATIC_CAST_EXPR:
1612 case REINTERPRET_CAST_EXPR:
1613 case CONST_CAST_EXPR:
1614 case DYNAMIC_CAST_EXPR:
1616 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1617 /* Now hash operands as usual. */
1627 if (TYPE_CANONICAL (arg))
1628 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1630 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1631 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1632 /* Otherwise just compare the types during lookup. */
1635 case tcc_declaration:
1637 return iterative_hash_expr (arg, val);
1640 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1642 unsigned n = cp_tree_operand_length (arg);
1643 for (i = 0; i < n; ++i)
1644 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1652 /* Unregister the specialization SPEC as a specialization of TMPL.
1653 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1654 if the SPEC was listed as a specialization of TMPL.
1656 Note that SPEC has been ggc_freed, so we can't look inside it. */
1659 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1664 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1665 elt.args = TI_ARGS (tinfo);
1666 elt.spec = NULL_TREE;
1668 entry = (spec_entry *) htab_find (decl_specializations, &elt);
1671 gcc_assert (entry->spec == spec || entry->spec == new_spec);
1672 gcc_assert (new_spec != NULL_TREE);
1673 entry->spec = new_spec;
1680 /* Compare an entry in the local specializations hash table P1 (which
1681 is really a pointer to a TREE_LIST) with P2 (which is really a
1685 eq_local_specializations (const void *p1, const void *p2)
1687 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1690 /* Hash P1, an entry in the local specializations table. */
1693 hash_local_specialization (const void* p1)
1695 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1698 /* Like register_specialization, but for local declarations. We are
1699 registering SPEC, an instantiation of TMPL. */
1702 register_local_specialization (tree spec, tree tmpl)
1706 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1707 htab_hash_pointer (tmpl), INSERT);
1708 *slot = build_tree_list (spec, tmpl);
1711 /* TYPE is a class type. Returns true if TYPE is an explicitly
1712 specialized class. */
1715 explicit_class_specialization_p (tree type)
1717 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1719 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1722 /* Print the list of functions at FNS, going through all the overloads
1723 for each element of the list. Alternatively, FNS can not be a
1724 TREE_LIST, in which case it will be printed together with all the
1727 MORE and *STR should respectively be FALSE and NULL when the function
1728 is called from the outside. They are used internally on recursive
1729 calls. print_candidates manages the two parameters and leaves NULL
1730 in *STR when it ends. */
1733 print_candidates_1 (tree fns, bool more, const char **str)
1736 char *spaces = NULL;
1738 for (fn = fns; fn; fn = OVL_NEXT (fn))
1739 if (TREE_CODE (fn) == TREE_LIST)
1741 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1742 print_candidates_1 (TREE_VALUE (fn2),
1743 TREE_CHAIN (fn2) || more, str);
1749 /* Pick the prefix string. */
1750 if (!more && !OVL_NEXT (fns))
1752 error ("candidate is: %+#D", OVL_CURRENT (fn));
1756 *str = _("candidates are:");
1757 spaces = get_spaces (*str);
1759 error ("%s %+#D", *str, OVL_CURRENT (fn));
1760 *str = spaces ? spaces : *str;
1770 /* Print the list of candidate FNS in an error message. FNS can also
1771 be a TREE_LIST of non-functions in the case of an ambiguous lookup. */
1774 print_candidates (tree fns)
1776 const char *str = NULL;
1777 print_candidates_1 (fns, false, &str);
1778 gcc_assert (str == NULL);
1781 /* Returns the template (one of the functions given by TEMPLATE_ID)
1782 which can be specialized to match the indicated DECL with the
1783 explicit template args given in TEMPLATE_ID. The DECL may be
1784 NULL_TREE if none is available. In that case, the functions in
1785 TEMPLATE_ID are non-members.
1787 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1788 specialization of a member template.
1790 The TEMPLATE_COUNT is the number of references to qualifying
1791 template classes that appeared in the name of the function. See
1792 check_explicit_specialization for a more accurate description.
1794 TSK indicates what kind of template declaration (if any) is being
1795 declared. TSK_TEMPLATE indicates that the declaration given by
1796 DECL, though a FUNCTION_DECL, has template parameters, and is
1797 therefore a template function.
1799 The template args (those explicitly specified and those deduced)
1800 are output in a newly created vector *TARGS_OUT.
1802 If it is impossible to determine the result, an error message is
1803 issued. The error_mark_node is returned to indicate failure. */
1806 determine_specialization (tree template_id,
1809 int need_member_template,
1815 tree explicit_targs;
1816 tree candidates = NULL_TREE;
1817 /* A TREE_LIST of templates of which DECL may be a specialization.
1818 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1819 corresponding TREE_PURPOSE is the set of template arguments that,
1820 when used to instantiate the template, would produce a function
1821 with the signature of DECL. */
1822 tree templates = NULL_TREE;
1824 cp_binding_level *b;
1826 *targs_out = NULL_TREE;
1828 if (template_id == error_mark_node || decl == error_mark_node)
1829 return error_mark_node;
1831 fns = TREE_OPERAND (template_id, 0);
1832 explicit_targs = TREE_OPERAND (template_id, 1);
1834 if (fns == error_mark_node)
1835 return error_mark_node;
1837 /* Check for baselinks. */
1838 if (BASELINK_P (fns))
1839 fns = BASELINK_FUNCTIONS (fns);
1841 if (!is_overloaded_fn (fns))
1843 error ("%qD is not a function template", fns);
1844 return error_mark_node;
1847 /* Count the number of template headers specified for this
1850 for (b = current_binding_level;
1851 b->kind == sk_template_parms;
1855 for (; fns; fns = OVL_NEXT (fns))
1857 tree fn = OVL_CURRENT (fns);
1859 if (TREE_CODE (fn) == TEMPLATE_DECL)
1861 tree decl_arg_types;
1864 /* In case of explicit specialization, we need to check if
1865 the number of template headers appearing in the specialization
1866 is correct. This is usually done in check_explicit_specialization,
1867 but the check done there cannot be exhaustive when specializing
1868 member functions. Consider the following code:
1870 template <> void A<int>::f(int);
1871 template <> template <> void A<int>::f(int);
1873 Assuming that A<int> is not itself an explicit specialization
1874 already, the first line specializes "f" which is a non-template
1875 member function, whilst the second line specializes "f" which
1876 is a template member function. So both lines are syntactically
1877 correct, and check_explicit_specialization does not reject
1880 Here, we can do better, as we are matching the specialization
1881 against the declarations. We count the number of template
1882 headers, and we check if they match TEMPLATE_COUNT + 1
1883 (TEMPLATE_COUNT is the number of qualifying template classes,
1884 plus there must be another header for the member template
1887 Notice that if header_count is zero, this is not a
1888 specialization but rather a template instantiation, so there
1889 is no check we can perform here. */
1890 if (header_count && header_count != template_count + 1)
1893 /* Check that the number of template arguments at the
1894 innermost level for DECL is the same as for FN. */
1895 if (current_binding_level->kind == sk_template_parms
1896 && !current_binding_level->explicit_spec_p
1897 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1898 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1899 (current_template_parms))))
1902 /* DECL might be a specialization of FN. */
1903 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1904 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1906 /* For a non-static member function, we need to make sure
1907 that the const qualification is the same. Since
1908 get_bindings does not try to merge the "this" parameter,
1909 we must do the comparison explicitly. */
1910 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1911 && !same_type_p (TREE_VALUE (fn_arg_types),
1912 TREE_VALUE (decl_arg_types)))
1915 /* Skip the "this" parameter and, for constructors of
1916 classes with virtual bases, the VTT parameter. A
1917 full specialization of a constructor will have a VTT
1918 parameter, but a template never will. */
1920 = skip_artificial_parms_for (decl, decl_arg_types);
1922 = skip_artificial_parms_for (fn, fn_arg_types);
1924 /* Check that the number of function parameters matches.
1926 template <class T> void f(int i = 0);
1927 template <> void f<int>();
1928 The specialization f<int> is invalid but is not caught
1929 by get_bindings below. */
1930 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1933 /* Function templates cannot be specializations; there are
1934 no partial specializations of functions. Therefore, if
1935 the type of DECL does not match FN, there is no
1937 if (tsk == tsk_template)
1939 if (compparms (fn_arg_types, decl_arg_types))
1940 candidates = tree_cons (NULL_TREE, fn, candidates);
1944 /* See whether this function might be a specialization of this
1946 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1949 /* We cannot deduce template arguments that when used to
1950 specialize TMPL will produce DECL. */
1953 /* Save this template, and the arguments deduced. */
1954 templates = tree_cons (targs, fn, templates);
1956 else if (need_member_template)
1957 /* FN is an ordinary member function, and we need a
1958 specialization of a member template. */
1960 else if (TREE_CODE (fn) != FUNCTION_DECL)
1961 /* We can get IDENTIFIER_NODEs here in certain erroneous
1964 else if (!DECL_FUNCTION_MEMBER_P (fn))
1965 /* This is just an ordinary non-member function. Nothing can
1966 be a specialization of that. */
1968 else if (DECL_ARTIFICIAL (fn))
1969 /* Cannot specialize functions that are created implicitly. */
1973 tree decl_arg_types;
1975 /* This is an ordinary member function. However, since
1976 we're here, we can assume it's enclosing class is a
1977 template class. For example,
1979 template <typename T> struct S { void f(); };
1980 template <> void S<int>::f() {}
1982 Here, S<int>::f is a non-template, but S<int> is a
1983 template class. If FN has the same type as DECL, we
1984 might be in business. */
1986 if (!DECL_TEMPLATE_INFO (fn))
1987 /* Its enclosing class is an explicit specialization
1988 of a template class. This is not a candidate. */
1991 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1992 TREE_TYPE (TREE_TYPE (fn))))
1993 /* The return types differ. */
1996 /* Adjust the type of DECL in case FN is a static member. */
1997 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1998 if (DECL_STATIC_FUNCTION_P (fn)
1999 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2000 decl_arg_types = TREE_CHAIN (decl_arg_types);
2002 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
2005 candidates = tree_cons (NULL_TREE, fn, candidates);
2009 if (templates && TREE_CHAIN (templates))
2015 It is possible for a specialization with a given function
2016 signature to be instantiated from more than one function
2017 template. In such cases, explicit specification of the
2018 template arguments must be used to uniquely identify the
2019 function template specialization being specialized.
2021 Note that here, there's no suggestion that we're supposed to
2022 determine which of the candidate templates is most
2023 specialized. However, we, also have:
2027 Partial ordering of overloaded function template
2028 declarations is used in the following contexts to select
2029 the function template to which a function template
2030 specialization refers:
2032 -- when an explicit specialization refers to a function
2035 So, we do use the partial ordering rules, at least for now.
2036 This extension can only serve to make invalid programs valid,
2037 so it's safe. And, there is strong anecdotal evidence that
2038 the committee intended the partial ordering rules to apply;
2039 the EDG front end has that behavior, and John Spicer claims
2040 that the committee simply forgot to delete the wording in
2041 [temp.expl.spec]. */
2042 tree tmpl = most_specialized_instantiation (templates);
2043 if (tmpl != error_mark_node)
2046 TREE_CHAIN (templates) = NULL_TREE;
2050 if (templates == NULL_TREE && candidates == NULL_TREE)
2052 error ("template-id %qD for %q+D does not match any template "
2053 "declaration", template_id, decl);
2054 if (header_count && header_count != template_count + 1)
2055 inform (input_location, "saw %d %<template<>%>, need %d for "
2056 "specializing a member function template",
2057 header_count, template_count + 1);
2058 return error_mark_node;
2060 else if ((templates && TREE_CHAIN (templates))
2061 || (candidates && TREE_CHAIN (candidates))
2062 || (templates && candidates))
2064 error ("ambiguous template specialization %qD for %q+D",
2066 candidates = chainon (candidates, templates);
2067 print_candidates (candidates);
2068 return error_mark_node;
2071 /* We have one, and exactly one, match. */
2074 tree fn = TREE_VALUE (candidates);
2075 *targs_out = copy_node (DECL_TI_ARGS (fn));
2076 /* DECL is a re-declaration or partial instantiation of a template
2078 if (TREE_CODE (fn) == TEMPLATE_DECL)
2080 /* It was a specialization of an ordinary member function in a
2082 return DECL_TI_TEMPLATE (fn);
2085 /* It was a specialization of a template. */
2086 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2087 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2089 *targs_out = copy_node (targs);
2090 SET_TMPL_ARGS_LEVEL (*targs_out,
2091 TMPL_ARGS_DEPTH (*targs_out),
2092 TREE_PURPOSE (templates));
2095 *targs_out = TREE_PURPOSE (templates);
2096 return TREE_VALUE (templates);
2099 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2100 but with the default argument values filled in from those in the
2104 copy_default_args_to_explicit_spec_1 (tree spec_types,
2107 tree new_spec_types;
2112 if (spec_types == void_list_node)
2113 return void_list_node;
2115 /* Substitute into the rest of the list. */
2117 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2118 TREE_CHAIN (tmpl_types));
2120 /* Add the default argument for this parameter. */
2121 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2122 TREE_VALUE (spec_types),
2126 /* DECL is an explicit specialization. Replicate default arguments
2127 from the template it specializes. (That way, code like:
2129 template <class T> void f(T = 3);
2130 template <> void f(double);
2133 works, as required.) An alternative approach would be to look up
2134 the correct default arguments at the call-site, but this approach
2135 is consistent with how implicit instantiations are handled. */
2138 copy_default_args_to_explicit_spec (tree decl)
2143 tree new_spec_types;
2147 tree object_type = NULL_TREE;
2148 tree in_charge = NULL_TREE;
2149 tree vtt = NULL_TREE;
2151 /* See if there's anything we need to do. */
2152 tmpl = DECL_TI_TEMPLATE (decl);
2153 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2154 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2155 if (TREE_PURPOSE (t))
2160 old_type = TREE_TYPE (decl);
2161 spec_types = TYPE_ARG_TYPES (old_type);
2163 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2165 /* Remove the this pointer, but remember the object's type for
2167 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2168 spec_types = TREE_CHAIN (spec_types);
2169 tmpl_types = TREE_CHAIN (tmpl_types);
2171 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2173 /* DECL may contain more parameters than TMPL due to the extra
2174 in-charge parameter in constructors and destructors. */
2175 in_charge = spec_types;
2176 spec_types = TREE_CHAIN (spec_types);
2178 if (DECL_HAS_VTT_PARM_P (decl))
2181 spec_types = TREE_CHAIN (spec_types);
2185 /* Compute the merged default arguments. */
2187 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2189 /* Compute the new FUNCTION_TYPE. */
2193 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2198 /* Put the in-charge parameter back. */
2199 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2200 TREE_VALUE (in_charge),
2203 new_type = build_method_type_directly (object_type,
2204 TREE_TYPE (old_type),
2208 new_type = build_function_type (TREE_TYPE (old_type),
2210 new_type = cp_build_type_attribute_variant (new_type,
2211 TYPE_ATTRIBUTES (old_type));
2212 new_type = build_exception_variant (new_type,
2213 TYPE_RAISES_EXCEPTIONS (old_type));
2214 TREE_TYPE (decl) = new_type;
2217 /* Check to see if the function just declared, as indicated in
2218 DECLARATOR, and in DECL, is a specialization of a function
2219 template. We may also discover that the declaration is an explicit
2220 instantiation at this point.
2222 Returns DECL, or an equivalent declaration that should be used
2223 instead if all goes well. Issues an error message if something is
2224 amiss. Returns error_mark_node if the error is not easily
2227 FLAGS is a bitmask consisting of the following flags:
2229 2: The function has a definition.
2230 4: The function is a friend.
2232 The TEMPLATE_COUNT is the number of references to qualifying
2233 template classes that appeared in the name of the function. For
2236 template <class T> struct S { void f(); };
2239 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2240 classes are not counted in the TEMPLATE_COUNT, so that in
2242 template <class T> struct S {};
2243 template <> struct S<int> { void f(); }
2244 template <> void S<int>::f();
2246 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2247 invalid; there should be no template <>.)
2249 If the function is a specialization, it is marked as such via
2250 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2251 is set up correctly, and it is added to the list of specializations
2252 for that template. */
2255 check_explicit_specialization (tree declarator,
2260 int have_def = flags & 2;
2261 int is_friend = flags & 4;
2262 int specialization = 0;
2263 int explicit_instantiation = 0;
2264 int member_specialization = 0;
2265 tree ctype = DECL_CLASS_CONTEXT (decl);
2266 tree dname = DECL_NAME (decl);
2271 if (!processing_specialization)
2274 tsk = tsk_excessive_parms;
2277 tsk = current_tmpl_spec_kind (template_count);
2282 if (processing_specialization)
2285 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2287 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2290 /* This could be something like:
2292 template <class T> void f(T);
2293 class S { friend void f<>(int); } */
2297 /* This case handles bogus declarations like template <>
2298 template <class T> void f<int>(); */
2300 error ("template-id %qD in declaration of primary template",
2307 case tsk_invalid_member_spec:
2308 /* The error has already been reported in
2309 check_specialization_scope. */
2310 return error_mark_node;
2312 case tsk_invalid_expl_inst:
2313 error ("template parameter list used in explicit instantiation");
2319 error ("definition provided for explicit instantiation");
2321 explicit_instantiation = 1;
2324 case tsk_excessive_parms:
2325 case tsk_insufficient_parms:
2326 if (tsk == tsk_excessive_parms)
2327 error ("too many template parameter lists in declaration of %qD",
2329 else if (template_header_count)
2330 error("too few template parameter lists in declaration of %qD", decl);
2332 error("explicit specialization of %qD must be introduced by "
2333 "%<template <>%>", decl);
2337 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2339 member_specialization = 1;
2345 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2347 /* This case handles bogus declarations like template <>
2348 template <class T> void f<int>(); */
2350 if (uses_template_parms (declarator))
2351 error ("function template partial specialization %qD "
2352 "is not allowed", declarator);
2354 error ("template-id %qD in declaration of primary template",
2359 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2360 /* This is a specialization of a member template, without
2361 specialization the containing class. Something like:
2363 template <class T> struct S {
2364 template <class U> void f (U);
2366 template <> template <class U> void S<int>::f(U) {}
2368 That's a specialization -- but of the entire template. */
2376 if (specialization || member_specialization)
2378 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2379 for (; t; t = TREE_CHAIN (t))
2380 if (TREE_PURPOSE (t))
2382 permerror (input_location,
2383 "default argument specified in explicit specialization");
2388 if (specialization || member_specialization || explicit_instantiation)
2390 tree tmpl = NULL_TREE;
2391 tree targs = NULL_TREE;
2393 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2394 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2398 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2403 /* If there is no class context, the explicit instantiation
2404 must be at namespace scope. */
2405 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2407 /* Find the namespace binding, using the declaration
2409 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2411 if (fns == error_mark_node || !is_overloaded_fn (fns))
2413 error ("%qD is not a template function", dname);
2414 fns = error_mark_node;
2418 tree fn = OVL_CURRENT (fns);
2419 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2420 CP_DECL_CONTEXT (fn)))
2421 error ("%qD is not declared in %qD",
2422 decl, current_namespace);
2426 declarator = lookup_template_function (fns, NULL_TREE);
2429 if (declarator == error_mark_node)
2430 return error_mark_node;
2432 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2434 if (!explicit_instantiation)
2435 /* A specialization in class scope. This is invalid,
2436 but the error will already have been flagged by
2437 check_specialization_scope. */
2438 return error_mark_node;
2441 /* It's not valid to write an explicit instantiation in
2444 class C { template void f(); }
2446 This case is caught by the parser. However, on
2449 template class C { void f(); };
2451 (which is invalid) we can get here. The error will be
2458 else if (ctype != NULL_TREE
2459 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2462 /* Find the list of functions in ctype that have the same
2463 name as the declared function. */
2464 tree name = TREE_OPERAND (declarator, 0);
2465 tree fns = NULL_TREE;
2468 if (constructor_name_p (name, ctype))
2470 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2472 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2473 : !CLASSTYPE_DESTRUCTORS (ctype))
2475 /* From [temp.expl.spec]:
2477 If such an explicit specialization for the member
2478 of a class template names an implicitly-declared
2479 special member function (clause _special_), the
2480 program is ill-formed.
2482 Similar language is found in [temp.explicit]. */
2483 error ("specialization of implicitly-declared special member function");
2484 return error_mark_node;
2487 name = is_constructor ? ctor_identifier : dtor_identifier;
2490 if (!DECL_CONV_FN_P (decl))
2492 idx = lookup_fnfields_1 (ctype, name);
2494 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2498 VEC(tree,gc) *methods;
2501 /* For a type-conversion operator, we cannot do a
2502 name-based lookup. We might be looking for `operator
2503 int' which will be a specialization of `operator T'.
2504 So, we find *all* the conversion operators, and then
2505 select from them. */
2508 methods = CLASSTYPE_METHOD_VEC (ctype);
2510 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2511 VEC_iterate (tree, methods, idx, ovl);
2514 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2515 /* There are no more conversion functions. */
2518 /* Glue all these conversion functions together
2519 with those we already have. */
2520 for (; ovl; ovl = OVL_NEXT (ovl))
2521 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2525 if (fns == NULL_TREE)
2527 error ("no member function %qD declared in %qT", name, ctype);
2528 return error_mark_node;
2531 TREE_OPERAND (declarator, 0) = fns;
2534 /* Figure out what exactly is being specialized at this point.
2535 Note that for an explicit instantiation, even one for a
2536 member function, we cannot tell apriori whether the
2537 instantiation is for a member template, or just a member
2538 function of a template class. Even if a member template is
2539 being instantiated, the member template arguments may be
2540 elided if they can be deduced from the rest of the
2542 tmpl = determine_specialization (declarator, decl,
2544 member_specialization,
2548 if (!tmpl || tmpl == error_mark_node)
2549 /* We couldn't figure out what this declaration was
2551 return error_mark_node;
2554 tree gen_tmpl = most_general_template (tmpl);
2556 if (explicit_instantiation)
2558 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2559 is done by do_decl_instantiation later. */
2561 int arg_depth = TMPL_ARGS_DEPTH (targs);
2562 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2564 if (arg_depth > parm_depth)
2566 /* If TMPL is not the most general template (for
2567 example, if TMPL is a friend template that is
2568 injected into namespace scope), then there will
2569 be too many levels of TARGS. Remove some of them
2574 new_targs = make_tree_vec (parm_depth);
2575 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2576 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2577 = TREE_VEC_ELT (targs, i);
2581 return instantiate_template (tmpl, targs, tf_error);
2584 /* If we thought that the DECL was a member function, but it
2585 turns out to be specializing a static member function,
2586 make DECL a static member function as well. */
2587 if (DECL_STATIC_FUNCTION_P (tmpl)
2588 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2589 revert_static_member_fn (decl);
2591 /* If this is a specialization of a member template of a
2592 template class, we want to return the TEMPLATE_DECL, not
2593 the specialization of it. */
2594 if (tsk == tsk_template)
2596 tree result = DECL_TEMPLATE_RESULT (tmpl);
2597 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2598 DECL_INITIAL (result) = NULL_TREE;
2602 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2603 DECL_SOURCE_LOCATION (result)
2604 = DECL_SOURCE_LOCATION (decl);
2605 /* We want to use the argument list specified in the
2606 definition, not in the original declaration. */
2607 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2608 for (parm = DECL_ARGUMENTS (result); parm;
2609 parm = DECL_CHAIN (parm))
2610 DECL_CONTEXT (parm) = result;
2612 return register_specialization (tmpl, gen_tmpl, targs,
2616 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2617 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2619 /* Inherit default function arguments from the template
2620 DECL is specializing. */
2621 copy_default_args_to_explicit_spec (decl);
2623 /* This specialization has the same protection as the
2624 template it specializes. */
2625 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2626 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2628 /* 7.1.1-1 [dcl.stc]
2630 A storage-class-specifier shall not be specified in an
2631 explicit specialization...
2633 The parser rejects these, so unless action is taken here,
2634 explicit function specializations will always appear with
2637 The action recommended by the C++ CWG in response to C++
2638 defect report 605 is to make the storage class and linkage
2639 of the explicit specialization match the templated function:
2641 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2643 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2645 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2646 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2648 /* This specialization has the same linkage and visibility as
2649 the function template it specializes. */
2650 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2651 if (! TREE_PUBLIC (decl))
2653 DECL_INTERFACE_KNOWN (decl) = 1;
2654 DECL_NOT_REALLY_EXTERN (decl) = 1;
2656 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2657 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2659 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2660 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2664 /* If DECL is a friend declaration, declared using an
2665 unqualified name, the namespace associated with DECL may
2666 have been set incorrectly. For example, in:
2668 template <typename T> void f(T);
2670 struct S { friend void f<int>(int); }
2673 we will have set the DECL_CONTEXT for the friend
2674 declaration to N, rather than to the global namespace. */
2675 if (DECL_NAMESPACE_SCOPE_P (decl))
2676 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2678 if (is_friend && !have_def)
2679 /* This is not really a declaration of a specialization.
2680 It's just the name of an instantiation. But, it's not
2681 a request for an instantiation, either. */
2682 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2683 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2684 /* This is indeed a specialization. In case of constructors
2685 and destructors, we need in-charge and not-in-charge
2686 versions in V3 ABI. */
2687 clone_function_decl (decl, /*update_method_vec_p=*/0);
2689 /* Register this specialization so that we can find it
2691 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2698 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2699 parameters. These are represented in the same format used for
2700 DECL_TEMPLATE_PARMS. */
2703 comp_template_parms (const_tree parms1, const_tree parms2)
2708 if (parms1 == parms2)
2711 for (p1 = parms1, p2 = parms2;
2712 p1 != NULL_TREE && p2 != NULL_TREE;
2713 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2715 tree t1 = TREE_VALUE (p1);
2716 tree t2 = TREE_VALUE (p2);
2719 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2720 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2722 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2725 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2727 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2728 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2730 /* If either of the template parameters are invalid, assume
2731 they match for the sake of error recovery. */
2732 if (parm1 == error_mark_node || parm2 == error_mark_node)
2735 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2738 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2739 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2740 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2742 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2747 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2748 /* One set of parameters has more parameters lists than the
2755 /* Determine whether PARM is a parameter pack. */
2758 template_parameter_pack_p (const_tree parm)
2760 /* Determine if we have a non-type template parameter pack. */
2761 if (TREE_CODE (parm) == PARM_DECL)
2762 return (DECL_TEMPLATE_PARM_P (parm)
2763 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2764 if (TREE_CODE (parm) == TEMPLATE_PARM_INDEX)
2765 return TEMPLATE_PARM_PARAMETER_PACK (parm);
2767 /* If this is a list of template parameters, we could get a
2768 TYPE_DECL or a TEMPLATE_DECL. */
2769 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2770 parm = TREE_TYPE (parm);
2772 /* Otherwise it must be a type template parameter. */
2773 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2774 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2775 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2778 /* Determine if T is a function parameter pack. */
2781 function_parameter_pack_p (const_tree t)
2783 if (t && TREE_CODE (t) == PARM_DECL)
2784 return FUNCTION_PARAMETER_PACK_P (t);
2788 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2789 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2792 get_function_template_decl (const_tree primary_func_tmpl_inst)
2794 if (! primary_func_tmpl_inst
2795 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2796 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2799 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2802 /* Return true iff the function parameter PARAM_DECL was expanded
2803 from the function parameter pack PACK. */
2806 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2808 if (DECL_ARTIFICIAL (param_decl)
2809 || !function_parameter_pack_p (pack))
2812 /* The parameter pack and its pack arguments have the same
2814 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2817 /* Determine whether ARGS describes a variadic template args list,
2818 i.e., one that is terminated by a template argument pack. */
2821 template_args_variadic_p (tree args)
2826 if (args == NULL_TREE)
2829 args = INNERMOST_TEMPLATE_ARGS (args);
2830 nargs = TREE_VEC_LENGTH (args);
2835 last_parm = TREE_VEC_ELT (args, nargs - 1);
2837 return ARGUMENT_PACK_P (last_parm);
2840 /* Generate a new name for the parameter pack name NAME (an
2841 IDENTIFIER_NODE) that incorporates its */
2844 make_ith_pack_parameter_name (tree name, int i)
2846 /* Munge the name to include the parameter index. */
2847 #define NUMBUF_LEN 128
2848 char numbuf[NUMBUF_LEN];
2852 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2853 newname_len = IDENTIFIER_LENGTH (name)
2854 + strlen (numbuf) + 2;
2855 newname = (char*)alloca (newname_len);
2856 snprintf (newname, newname_len,
2857 "%s#%i", IDENTIFIER_POINTER (name), i);
2858 return get_identifier (newname);
2861 /* Return true if T is a primary function, class or alias template
2865 primary_template_instantiation_p (const_tree t)
2870 if (TREE_CODE (t) == FUNCTION_DECL)
2871 return DECL_LANG_SPECIFIC (t)
2872 && DECL_TEMPLATE_INSTANTIATION (t)
2873 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2874 else if (CLASS_TYPE_P (t) && !TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
2875 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2876 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2878 && TYPE_TEMPLATE_INFO (t)
2879 && PRIMARY_TEMPLATE_P (TYPE_TI_TEMPLATE (t))
2880 && DECL_TEMPLATE_INSTANTIATION (TYPE_NAME (t)))
2885 /* Return true if PARM is a template template parameter. */
2888 template_template_parameter_p (const_tree parm)
2890 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2893 /* Return the template parameters of T if T is a
2894 primary template instantiation, NULL otherwise. */
2897 get_primary_template_innermost_parameters (const_tree t)
2899 tree parms = NULL, template_info = NULL;
2901 if ((template_info = get_template_info (t))
2902 && primary_template_instantiation_p (t))
2903 parms = INNERMOST_TEMPLATE_PARMS
2904 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2909 /* Return the template parameters of the LEVELth level from the full list
2910 of template parameters PARMS. */
2913 get_template_parms_at_level (tree parms, int level)
2917 || TREE_CODE (parms) != TREE_LIST
2918 || level > TMPL_PARMS_DEPTH (parms))
2921 for (p = parms; p; p = TREE_CHAIN (p))
2922 if (TMPL_PARMS_DEPTH (p) == level)
2928 /* Returns the template arguments of T if T is a template instantiation,
2932 get_template_innermost_arguments (const_tree t)
2934 tree args = NULL, template_info = NULL;
2936 if ((template_info = get_template_info (t))
2937 && TI_ARGS (template_info))
2938 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2943 /* Return the argument pack elements of T if T is a template argument pack,
2947 get_template_argument_pack_elems (const_tree t)
2949 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2950 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2953 return ARGUMENT_PACK_ARGS (t);
2956 /* Structure used to track the progress of find_parameter_packs_r. */
2957 struct find_parameter_pack_data
2959 /* TREE_LIST that will contain all of the parameter packs found by
2961 tree* parameter_packs;
2963 /* Set of AST nodes that have been visited by the traversal. */
2964 struct pointer_set_t *visited;
2967 /* Identifies all of the argument packs that occur in a template
2968 argument and appends them to the TREE_LIST inside DATA, which is a
2969 find_parameter_pack_data structure. This is a subroutine of
2970 make_pack_expansion and uses_parameter_packs. */
2972 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2975 struct find_parameter_pack_data* ppd =
2976 (struct find_parameter_pack_data*)data;
2977 bool parameter_pack_p = false;
2979 /* Handle type aliases/typedefs. */
2982 && TREE_CODE (TYPE_NAME (t)) == TYPE_DECL
2983 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
2985 if (TYPE_TEMPLATE_INFO (t))
2986 cp_walk_tree (&TYPE_TI_ARGS (t),
2987 &find_parameter_packs_r,
2993 /* Identify whether this is a parameter pack or not. */
2994 switch (TREE_CODE (t))
2996 case TEMPLATE_PARM_INDEX:
2997 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2998 parameter_pack_p = true;
3001 case TEMPLATE_TYPE_PARM:
3002 t = TYPE_MAIN_VARIANT (t);
3003 case TEMPLATE_TEMPLATE_PARM:
3004 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3005 parameter_pack_p = true;
3009 if (FUNCTION_PARAMETER_PACK_P (t))
3011 /* We don't want to walk into the type of a PARM_DECL,
3012 because we don't want to see the type parameter pack. */
3014 parameter_pack_p = true;
3019 parameter_pack_p = true;
3022 /* Not a parameter pack. */
3026 if (parameter_pack_p)
3028 /* Add this parameter pack to the list. */
3029 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
3033 cp_walk_tree (&TYPE_CONTEXT (t),
3034 &find_parameter_packs_r, ppd, ppd->visited);
3036 /* This switch statement will return immediately if we don't find a
3038 switch (TREE_CODE (t))
3040 case TEMPLATE_PARM_INDEX:
3043 case BOUND_TEMPLATE_TEMPLATE_PARM:
3044 /* Check the template itself. */
3045 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
3046 &find_parameter_packs_r, ppd, ppd->visited);
3047 /* Check the template arguments. */
3048 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
3053 case TEMPLATE_TYPE_PARM:
3054 case TEMPLATE_TEMPLATE_PARM:
3061 if (TYPE_PTRMEMFUNC_P (t))
3067 if (TYPE_TEMPLATE_INFO (t))
3068 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3069 &find_parameter_packs_r, ppd, ppd->visited);
3076 cp_walk_tree (&TREE_TYPE (t),
3077 &find_parameter_packs_r, ppd, ppd->visited);
3081 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3086 case TYPE_PACK_EXPANSION:
3087 case EXPR_PACK_EXPANSION:
3092 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3097 case IDENTIFIER_NODE:
3098 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3110 /* Determines if the expression or type T uses any parameter packs. */
3112 uses_parameter_packs (tree t)
3114 tree parameter_packs = NULL_TREE;
3115 struct find_parameter_pack_data ppd;
3116 ppd.parameter_packs = ¶meter_packs;
3117 ppd.visited = pointer_set_create ();
3118 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3119 pointer_set_destroy (ppd.visited);
3120 return parameter_packs != NULL_TREE;
3123 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3124 representation a base-class initializer into a parameter pack
3125 expansion. If all goes well, the resulting node will be an
3126 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3129 make_pack_expansion (tree arg)
3132 tree parameter_packs = NULL_TREE;
3133 bool for_types = false;
3134 struct find_parameter_pack_data ppd;
3136 if (!arg || arg == error_mark_node)
3139 if (TREE_CODE (arg) == TREE_LIST)
3141 /* The only time we will see a TREE_LIST here is for a base
3142 class initializer. In this case, the TREE_PURPOSE will be a
3143 _TYPE node (representing the base class expansion we're
3144 initializing) and the TREE_VALUE will be a TREE_LIST
3145 containing the initialization arguments.
3147 The resulting expansion looks somewhat different from most
3148 expansions. Rather than returning just one _EXPANSION, we
3149 return a TREE_LIST whose TREE_PURPOSE is a
3150 TYPE_PACK_EXPANSION containing the bases that will be
3151 initialized. The TREE_VALUE will be identical to the
3152 original TREE_VALUE, which is a list of arguments that will
3153 be passed to each base. We do not introduce any new pack
3154 expansion nodes into the TREE_VALUE (although it is possible
3155 that some already exist), because the TREE_PURPOSE and
3156 TREE_VALUE all need to be expanded together with the same
3157 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3158 resulting TREE_PURPOSE will mention the parameter packs in
3159 both the bases and the arguments to the bases. */
3162 tree parameter_packs = NULL_TREE;
3164 /* Determine which parameter packs will be used by the base
3166 ppd.visited = pointer_set_create ();
3167 ppd.parameter_packs = ¶meter_packs;
3168 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3171 if (parameter_packs == NULL_TREE)
3173 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3174 pointer_set_destroy (ppd.visited);
3175 return error_mark_node;
3178 if (TREE_VALUE (arg) != void_type_node)
3180 /* Collect the sets of parameter packs used in each of the
3181 initialization arguments. */
3182 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3184 /* Determine which parameter packs will be expanded in this
3186 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3191 pointer_set_destroy (ppd.visited);
3193 /* Create the pack expansion type for the base type. */
3194 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3195 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3196 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3198 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3199 they will rarely be compared to anything. */
3200 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3202 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3205 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3208 /* Build the PACK_EXPANSION_* node. */
3210 ? cxx_make_type (TYPE_PACK_EXPANSION)
3211 : make_node (EXPR_PACK_EXPANSION);
3212 SET_PACK_EXPANSION_PATTERN (result, arg);
3213 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3215 /* Propagate type and const-expression information. */
3216 TREE_TYPE (result) = TREE_TYPE (arg);
3217 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3220 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3221 they will rarely be compared to anything. */
3222 SET_TYPE_STRUCTURAL_EQUALITY (result);
3224 /* Determine which parameter packs will be expanded. */
3225 ppd.parameter_packs = ¶meter_packs;
3226 ppd.visited = pointer_set_create ();
3227 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3228 pointer_set_destroy (ppd.visited);
3230 /* Make sure we found some parameter packs. */
3231 if (parameter_packs == NULL_TREE)
3234 error ("expansion pattern %<%T%> contains no argument packs", arg);
3236 error ("expansion pattern %<%E%> contains no argument packs", arg);
3237 return error_mark_node;
3239 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3244 /* Checks T for any "bare" parameter packs, which have not yet been
3245 expanded, and issues an error if any are found. This operation can
3246 only be done on full expressions or types (e.g., an expression
3247 statement, "if" condition, etc.), because we could have expressions like:
3249 foo(f(g(h(args)))...)
3251 where "args" is a parameter pack. check_for_bare_parameter_packs
3252 should not be called for the subexpressions args, h(args),
3253 g(h(args)), or f(g(h(args))), because we would produce erroneous
3256 Returns TRUE and emits an error if there were bare parameter packs,
3257 returns FALSE otherwise. */
3259 check_for_bare_parameter_packs (tree t)
3261 tree parameter_packs = NULL_TREE;
3262 struct find_parameter_pack_data ppd;
3264 if (!processing_template_decl || !t || t == error_mark_node)
3267 if (TREE_CODE (t) == TYPE_DECL)
3270 ppd.parameter_packs = ¶meter_packs;
3271 ppd.visited = pointer_set_create ();
3272 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3273 pointer_set_destroy (ppd.visited);
3275 if (parameter_packs)
3277 error ("parameter packs not expanded with %<...%>:");
3278 while (parameter_packs)
3280 tree pack = TREE_VALUE (parameter_packs);
3281 tree name = NULL_TREE;
3283 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3284 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3285 name = TYPE_NAME (pack);
3286 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3287 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3289 name = DECL_NAME (pack);
3292 inform (input_location, " %qD", name);
3294 inform (input_location, " <anonymous>");
3296 parameter_packs = TREE_CHAIN (parameter_packs);
3305 /* Expand any parameter packs that occur in the template arguments in
3308 expand_template_argument_pack (tree args)
3310 tree result_args = NULL_TREE;
3311 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3312 int num_result_args = -1;
3313 int non_default_args_count = -1;
3315 /* First, determine if we need to expand anything, and the number of
3316 slots we'll need. */
3317 for (in_arg = 0; in_arg < nargs; ++in_arg)
3319 tree arg = TREE_VEC_ELT (args, in_arg);
3320 if (arg == NULL_TREE)
3322 if (ARGUMENT_PACK_P (arg))
3324 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3325 if (num_result_args < 0)
3326 num_result_args = in_arg + num_packed;
3328 num_result_args += num_packed;
3332 if (num_result_args >= 0)
3337 /* If no expansion is necessary, we're done. */
3338 if (num_result_args < 0)
3341 /* Expand arguments. */
3342 result_args = make_tree_vec (num_result_args);
3343 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3344 non_default_args_count =
3345 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3346 for (in_arg = 0; in_arg < nargs; ++in_arg)
3348 tree arg = TREE_VEC_ELT (args, in_arg);
3349 if (ARGUMENT_PACK_P (arg))
3351 tree packed = ARGUMENT_PACK_ARGS (arg);
3352 int i, num_packed = TREE_VEC_LENGTH (packed);
3353 for (i = 0; i < num_packed; ++i, ++out_arg)
3354 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3355 if (non_default_args_count > 0)
3356 non_default_args_count += num_packed;
3360 TREE_VEC_ELT (result_args, out_arg) = arg;
3364 if (non_default_args_count >= 0)
3365 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3369 /* Checks if DECL shadows a template parameter.
3371 [temp.local]: A template-parameter shall not be redeclared within its
3372 scope (including nested scopes).
3374 Emits an error and returns TRUE if the DECL shadows a parameter,
3375 returns FALSE otherwise. */
3378 check_template_shadow (tree decl)
3382 /* If we're not in a template, we can't possibly shadow a template
3384 if (!current_template_parms)
3387 /* Figure out what we're shadowing. */
3388 if (TREE_CODE (decl) == OVERLOAD)
3389 decl = OVL_CURRENT (decl);
3390 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3392 /* If there's no previous binding for this name, we're not shadowing
3393 anything, let alone a template parameter. */
3397 /* If we're not shadowing a template parameter, we're done. Note
3398 that OLDDECL might be an OVERLOAD (or perhaps even an
3399 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3401 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3404 /* We check for decl != olddecl to avoid bogus errors for using a
3405 name inside a class. We check TPFI to avoid duplicate errors for
3406 inline member templates. */
3408 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3411 error ("declaration of %q+#D", decl);
3412 error (" shadows template parm %q+#D", olddecl);
3416 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3417 ORIG_LEVEL, DECL, and TYPE. NUM_SIBLINGS is the total number of
3418 template parameters. */
3421 build_template_parm_index (int index,
3428 tree t = make_node (TEMPLATE_PARM_INDEX);
3429 TEMPLATE_PARM_IDX (t) = index;
3430 TEMPLATE_PARM_LEVEL (t) = level;
3431 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3432 TEMPLATE_PARM_NUM_SIBLINGS (t) = num_siblings;
3433 TEMPLATE_PARM_DECL (t) = decl;
3434 TREE_TYPE (t) = type;
3435 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3436 TREE_READONLY (t) = TREE_READONLY (decl);
3441 /* Find the canonical type parameter for the given template type
3442 parameter. Returns the canonical type parameter, which may be TYPE
3443 if no such parameter existed. */
3446 canonical_type_parameter (tree type)
3449 int idx = TEMPLATE_TYPE_IDX (type);
3450 if (!canonical_template_parms)
3451 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3453 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3454 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3456 list = VEC_index (tree, canonical_template_parms, idx);
3457 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3458 list = TREE_CHAIN (list);
3461 return TREE_VALUE (list);
3464 VEC_replace(tree, canonical_template_parms, idx,
3465 tree_cons (NULL_TREE, type,
3466 VEC_index (tree, canonical_template_parms, idx)));
3471 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3472 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3473 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3474 new one is created. */
3477 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3478 tsubst_flags_t complain)
3480 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3481 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3482 != TEMPLATE_PARM_LEVEL (index) - levels)
3483 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3485 tree orig_decl = TEMPLATE_PARM_DECL (index);
3488 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3489 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3490 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3491 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3492 DECL_ARTIFICIAL (decl) = 1;
3493 SET_DECL_TEMPLATE_PARM_P (decl);
3495 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3496 TEMPLATE_PARM_LEVEL (index) - levels,
3497 TEMPLATE_PARM_ORIG_LEVEL (index),
3498 TEMPLATE_PARM_NUM_SIBLINGS (index),
3500 TEMPLATE_PARM_DESCENDANTS (index) = t;
3501 TEMPLATE_PARM_PARAMETER_PACK (t)
3502 = TEMPLATE_PARM_PARAMETER_PACK (index);
3504 /* Template template parameters need this. */
3505 if (TREE_CODE (decl) == TEMPLATE_DECL)
3506 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3507 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3511 return TEMPLATE_PARM_DESCENDANTS (index);
3514 /* Process information from new template parameter PARM and append it
3515 to the LIST being built. This new parameter is a non-type
3516 parameter iff IS_NON_TYPE is true. This new parameter is a
3517 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3518 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3519 parameter list PARM belongs to. This is used used to create a
3520 proper canonical type for the type of PARM that is to be created,
3521 iff PARM is a type. If the size is not known, this parameter shall
3525 process_template_parm (tree list, location_t parm_loc, tree parm,
3526 bool is_non_type, bool is_parameter_pack,
3527 unsigned num_template_parms)
3534 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3535 defval = TREE_PURPOSE (parm);
3539 tree p = tree_last (list);
3541 if (p && TREE_VALUE (p) != error_mark_node)
3544 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3545 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3547 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3557 parm = TREE_VALUE (parm);
3559 SET_DECL_TEMPLATE_PARM_P (parm);
3561 if (TREE_TYPE (parm) == error_mark_node)
3563 err_parm_list = build_tree_list (defval, parm);
3564 TREE_VALUE (err_parm_list) = error_mark_node;
3565 return chainon (list, err_parm_list);
3571 The top-level cv-qualifiers on the template-parameter are
3572 ignored when determining its type. */
3573 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3574 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3576 err_parm_list = build_tree_list (defval, parm);
3577 TREE_VALUE (err_parm_list) = error_mark_node;
3578 return chainon (list, err_parm_list);
3581 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3583 /* This template parameter is not a parameter pack, but it
3584 should be. Complain about "bare" parameter packs. */
3585 check_for_bare_parameter_packs (TREE_TYPE (parm));
3587 /* Recover by calling this a parameter pack. */
3588 is_parameter_pack = true;
3592 /* A template parameter is not modifiable. */
3593 TREE_CONSTANT (parm) = 1;
3594 TREE_READONLY (parm) = 1;
3595 decl = build_decl (parm_loc,
3596 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3597 TREE_CONSTANT (decl) = 1;
3598 TREE_READONLY (decl) = 1;
3599 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3600 = build_template_parm_index (idx, processing_template_decl,
3601 processing_template_decl,
3603 decl, TREE_TYPE (parm));
3605 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3606 = is_parameter_pack;
3611 parm = TREE_VALUE (TREE_VALUE (parm));
3613 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3615 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3616 /* This is for distinguishing between real templates and template
3617 template parameters */
3618 TREE_TYPE (parm) = t;
3619 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3624 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3625 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3626 decl = build_decl (parm_loc,
3627 TYPE_DECL, parm, t);
3630 TYPE_NAME (t) = decl;
3631 TYPE_STUB_DECL (t) = decl;
3633 TEMPLATE_TYPE_PARM_INDEX (t)
3634 = build_template_parm_index (idx, processing_template_decl,
3635 processing_template_decl,
3637 decl, TREE_TYPE (parm));
3638 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3639 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3641 DECL_ARTIFICIAL (decl) = 1;
3642 SET_DECL_TEMPLATE_PARM_P (decl);
3644 parm = build_tree_list (defval, parm);
3645 return chainon (list, parm);
3648 /* The end of a template parameter list has been reached. Process the
3649 tree list into a parameter vector, converting each parameter into a more
3650 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3654 end_template_parm_list (tree parms)
3658 tree saved_parmlist = make_tree_vec (list_length (parms));
3660 current_template_parms
3661 = tree_cons (size_int (processing_template_decl),
3662 saved_parmlist, current_template_parms);
3664 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3666 next = TREE_CHAIN (parm);
3667 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3668 TREE_CHAIN (parm) = NULL_TREE;
3671 --processing_template_parmlist;
3673 return saved_parmlist;
3676 /* Create a new type almost identical to TYPE but which has the
3677 following differences:
3679 1/ T has a new TEMPLATE_PARM_INDEX that carries the new number of
3680 template sibling parameters of T.
3682 2/ T has a new canonical type that matches the new number
3685 3/ From now on, T is going to be what lookups referring to the
3686 name of TYPE will return. No lookup should return TYPE anymore.
3688 NUM_PARMS is the new number of sibling parms TYPE belongs to.
3690 This is a subroutine of fixup_template_parms. */
3693 fixup_template_type_parm_type (tree type, int num_parms)
3695 tree orig_idx = TEMPLATE_TYPE_PARM_INDEX (type), idx;
3697 /* This is the decl which name is inserted into the symbol table for
3698 the template parm type. So whenever we lookup the type name, this
3699 is the DECL we get. */
3702 /* Do not fix up the type twice. */
3703 if (orig_idx && TEMPLATE_PARM_NUM_SIBLINGS (orig_idx) != 0)
3706 t = copy_type (type);
3707 decl = TYPE_NAME (t);
3709 TYPE_MAIN_VARIANT (t) = t;
3710 TYPE_NEXT_VARIANT (t)= NULL_TREE;
3711 TYPE_POINTER_TO (t) = 0;
3712 TYPE_REFERENCE_TO (t) = 0;
3714 idx = build_template_parm_index (TEMPLATE_PARM_IDX (orig_idx),
3715 TEMPLATE_PARM_LEVEL (orig_idx),
3716 TEMPLATE_PARM_ORIG_LEVEL (orig_idx),
3719 TEMPLATE_PARM_DESCENDANTS (idx) = TEMPLATE_PARM_DESCENDANTS (orig_idx);
3720 TEMPLATE_PARM_PARAMETER_PACK (idx) = TEMPLATE_PARM_PARAMETER_PACK (orig_idx);
3721 TEMPLATE_TYPE_PARM_INDEX (t) = idx;
3723 TYPE_STUB_DECL (t) = decl;
3724 TEMPLATE_TYPE_DECL (t) = decl;
3725 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
3726 TREE_TYPE (DECL_TEMPLATE_RESULT (decl)) = t;
3728 /* Update the type associated to the type name stored in the symbol
3729 table. Now, whenever the type name is looked up, the resulting
3730 type is properly fixed up. */
3731 TREE_TYPE (decl) = t;
3733 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3738 /* Create and return a new TEMPLATE_PARM_INDEX that is almost
3739 identical to I, but that is fixed up as to:
3741 1/ carry the number of sibling parms (NUM_PARMS) of the template
3742 parm represented by I.
3744 2/ replace all references to template parm types declared before I
3745 (in the same template parm list as I) by references to template
3746 parm types contained in ARGS. ARGS should contain the list of
3747 template parms that have been fixed up so far, in a form suitable
3748 to be passed to tsubst.
3750 This is a subroutine of fixup_template_parms. */
3753 fixup_template_parm_index (tree i, tree args, int num_parms)
3755 tree index, decl, type;
3758 || TREE_CODE (i) != TEMPLATE_PARM_INDEX
3759 /* Do not fix up the index twice. */
3760 || (TEMPLATE_PARM_NUM_SIBLINGS (i) != 0))
3763 decl = TEMPLATE_PARM_DECL (i);
3764 type = TREE_TYPE (decl);
3766 index = build_template_parm_index (TEMPLATE_PARM_IDX (i),
3767 TEMPLATE_PARM_LEVEL (i),
3768 TEMPLATE_PARM_ORIG_LEVEL (i),
3772 TEMPLATE_PARM_DESCENDANTS (index) = TEMPLATE_PARM_DESCENDANTS (i);
3773 TEMPLATE_PARM_PARAMETER_PACK (index) = TEMPLATE_PARM_PARAMETER_PACK (i);
3775 type = tsubst (type, args, tf_none, NULL_TREE);
3777 TREE_TYPE (decl) = type;
3778 TREE_TYPE (index) = type;
3784 This is a subroutine of fixup_template_parms.
3786 It computes the canonical type of the type of the template
3787 parameter PARM_DESC and update all references to that type so that
3788 they use the newly computed canonical type. No access check is
3789 performed during the fixup. PARM_DESC is a TREE_LIST which
3790 TREE_VALUE is the template parameter and its TREE_PURPOSE is the
3791 default argument of the template parm if any. IDX is the index of
3792 the template parameter, starting at 0. NUM_PARMS is the number of
3793 template parameters in the set PARM_DESC belongs to. ARGLIST is a
3794 TREE_VEC containing the full set of template parameters in a form
3795 suitable to be passed to substs functions as their ARGS
3796 argument. This is what current_template_args returns for a given
3797 template. The innermost vector of args in ARGLIST is the set of
3798 template parms that have been fixed up so far. This function adds
3799 the fixed up parameter into that vector. */
3802 fixup_template_parm (tree parm_desc,
3807 tree parm = TREE_VALUE (parm_desc);
3808 tree fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3810 push_deferring_access_checks (dk_no_check);
3812 if (TREE_CODE (parm) == TYPE_DECL)
3814 /* PARM is a template type parameter. Fix up its type, add
3815 the fixed-up template parm to the vector of fixed-up
3816 template parms so far, and substitute the fixed-up
3817 template parms into the default argument of this
3820 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3821 TREE_TYPE (parm) = t;
3823 TREE_VEC_ELT (fixedup_args, idx) = template_parm_to_arg (parm_desc);
3825 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3827 /* PARM is a template template parameter. This is going to
3829 tree tparms, targs, innermost_args, t;
3832 /* First, fix up the parms of the template template parm
3833 because the parms are involved in defining the new canonical
3834 type of the template template parm. */
3836 /* So we need to substitute the template parm types that have
3837 been fixed up so far into the template parms of this template
3838 template parm. E.g, consider this:
3840 template<class T, template<T u> class TT> class S;
3842 In this case we want to substitute T into the
3843 template parameters of TT.
3845 So let's walk the template parms of PARM here, and
3846 tsubst ARGLIST into into each of the template
3849 /* For this substitution we need to build the full set of
3850 template parameters and use that as arguments for the
3851 tsubsting function. */
3852 tparms = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (parm));
3854 /* This will contain the innermost parms of PARM into which
3855 we have substituted so far. */
3856 innermost_args = make_tree_vec (TREE_VEC_LENGTH (tparms));
3857 targs = add_to_template_args (arglist, innermost_args);
3858 for (j = 0; j < TREE_VEC_LENGTH (tparms); ++j)
3862 parameter = TREE_VEC_ELT (tparms, j);
3864 /* INNERMOST_ARGS needs to have at least the same number
3865 of elements as the index PARAMETER, ortherwise
3866 tsubsting into PARAMETER will result in partially
3867 instantiating it, reducing its tempate parm
3868 level. Let's tactically fill INNERMOST_ARGS for that
3870 TREE_VEC_ELT (innermost_args, j) =
3871 template_parm_to_arg (parameter);
3873 fixup_template_parm (parameter, j,
3874 TREE_VEC_LENGTH (tparms),
3878 /* Now fix up the type of the template template parm. */
3880 t = fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3881 TREE_TYPE (parm) = t;
3883 TREE_VEC_ELT (fixedup_args, idx) =
3884 template_parm_to_arg (parm_desc);
3886 else if (TREE_CODE (parm) == PARM_DECL)
3888 /* PARM is a non-type template parameter. We need to:
3890 * Fix up its TEMPLATE_PARM_INDEX to make it carry the
3891 proper number of sibling parameters.
3893 * Make lookups of the template parameter return a reference
3894 to the fixed-up index. No lookup should return references
3895 to the former index anymore.
3897 * Substitute the template parms that got fixed up so far
3899 * into the type of PARM. */
3901 tree index = DECL_INITIAL (parm);
3903 /* PUSHED_DECL is the decl added to the symbol table with
3904 the name of the parameter. E,g:
3906 template<class T, T u> //#0
3907 auto my_function(T t) -> decltype(u); //#1
3909 Here, when looking up u at //#1, we get the decl of u
3910 resulting from the declaration in #0. This is what
3911 PUSHED_DECL is. We need to replace the reference to the
3912 old TEMPLATE_PARM_INDEX carried by PUSHED_DECL by the
3913 fixed-up TEMPLATE_PARM_INDEX. */
3914 tree pushed_decl = TEMPLATE_PARM_DECL (index);
3916 /* Let's fix up the TEMPLATE_PARM_INDEX then. Note that we must
3917 fixup the type of PUSHED_DECL as well and luckily
3918 fixup_template_parm_index does it for us too. */
3919 tree fixed_up_index =
3920 fixup_template_parm_index (index, arglist, num_parms);
3922 DECL_INITIAL (pushed_decl) = DECL_INITIAL (parm) = fixed_up_index;
3924 /* Add this fixed up PARM to the template parms we've fixed
3925 up so far and use that to substitute the fixed-up
3926 template parms into the type of PARM. */
3927 TREE_VEC_ELT (fixedup_args, idx) =
3928 template_parm_to_arg (parm_desc);
3929 TREE_TYPE (parm) = tsubst (TREE_TYPE (parm), arglist,
3930 tf_none, NULL_TREE);
3933 TREE_PURPOSE (parm_desc) =
3934 tsubst_template_arg (TREE_PURPOSE (parm_desc),
3935 arglist, tf_none, parm);
3937 pop_deferring_access_checks ();
3940 /* Walk the current template parms and properly compute the canonical
3941 types of the dependent types created during
3942 cp_parser_template_parameter_list. */
3945 fixup_template_parms (void)
3952 parameter_vec = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3953 if (parameter_vec == NULL_TREE)
3956 num_parms = TREE_VEC_LENGTH (parameter_vec);
3958 /* This vector contains the current innermost template parms that
3959 have been fixed up so far. The form of FIXEDUP_ARGS is suitable
3960 to be passed to tsubst* functions as their ARGS argument. */
3961 fixedup_args = make_tree_vec (num_parms);
3963 /* This vector contains the full set of template parms in a form
3964 suitable to be passed to substs functions as their ARGS
3966 arglist = current_template_args ();
3967 arglist = add_outermost_template_args (arglist, fixedup_args);
3969 /* Let's do the proper fixup now. */
3970 for (i = 0; i < num_parms; ++i)
3971 fixup_template_parm (TREE_VEC_ELT (parameter_vec, i),
3972 i, num_parms, arglist);
3975 /* end_template_decl is called after a template declaration is seen. */
3978 end_template_decl (void)
3980 reset_specialization ();
3982 if (! processing_template_decl)
3985 /* This matches the pushlevel in begin_template_parm_list. */
3988 --processing_template_decl;
3989 current_template_parms = TREE_CHAIN (current_template_parms);
3992 /* Takes a TREE_LIST representing a template parameter and convert it
3993 into an argument suitable to be passed to the type substitution
3994 functions. Note that If the TREE_LIST contains an error_mark
3995 node, the returned argument is error_mark_node. */
3998 template_parm_to_arg (tree t)
4002 || TREE_CODE (t) != TREE_LIST)
4005 if (error_operand_p (TREE_VALUE (t)))
4006 return error_mark_node;
4010 if (TREE_CODE (t) == TYPE_DECL
4011 || TREE_CODE (t) == TEMPLATE_DECL)
4015 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
4017 /* Turn this argument into a TYPE_ARGUMENT_PACK
4018 with a single element, which expands T. */
4019 tree vec = make_tree_vec (1);
4020 #ifdef ENABLE_CHECKING
4021 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4022 (vec, TREE_VEC_LENGTH (vec));
4024 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4026 t = cxx_make_type (TYPE_ARGUMENT_PACK);
4027 SET_ARGUMENT_PACK_ARGS (t, vec);
4032 t = DECL_INITIAL (t);
4034 if (TEMPLATE_PARM_PARAMETER_PACK (t))
4036 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
4037 with a single element, which expands T. */
4038 tree vec = make_tree_vec (1);
4039 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
4040 #ifdef ENABLE_CHECKING
4041 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4042 (vec, TREE_VEC_LENGTH (vec));
4044 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4046 t = make_node (NONTYPE_ARGUMENT_PACK);
4047 SET_ARGUMENT_PACK_ARGS (t, vec);
4048 TREE_TYPE (t) = type;
4054 /* This function returns TRUE if PARM_PACK is a template parameter
4055 pack and if ARG_PACK is what template_parm_to_arg returned when
4056 passed PARM_PACK. */
4059 arg_from_parm_pack_p (tree arg_pack, tree parm_pack)
4061 /* For clarity in the comments below let's use the representation
4062 argument_pack<elements>' to denote an argument pack and its
4065 In the 'if' block below, we want to detect cases where
4066 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to
4067 check if ARG_PACK is an argument pack which sole element is
4068 the expansion of PARM_PACK. That argument pack is typically
4069 created by template_parm_to_arg when passed a parameter
4073 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
4074 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
4076 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
4077 tree pattern = PACK_EXPANSION_PATTERN (expansion);
4078 /* So we have an argument_pack<P...>. We want to test if P
4079 is actually PARM_PACK. We will not use cp_tree_equal to
4080 test P and PARM_PACK because during type fixup (by
4081 fixup_template_parm) P can be a pre-fixup version of a
4082 type and PARM_PACK be its post-fixup version.
4083 cp_tree_equal would consider them as different even
4084 though we would want to consider them compatible for our
4085 precise purpose here.
4087 Thus we are going to consider that P and PARM_PACK are
4088 compatible if they have the same DECL. */
4089 if ((/* If ARG_PACK is a type parameter pack named by the
4090 same DECL as parm_pack ... */
4092 && TYPE_P (parm_pack)
4093 && TYPE_NAME (pattern) == TYPE_NAME (parm_pack))
4094 /* ... or if PARM_PACK is a non-type parameter named by the
4095 same DECL as ARG_PACK. Note that PARM_PACK being a
4096 non-type parameter means it's either a PARM_DECL or a
4097 TEMPLATE_PARM_INDEX. */
4098 || (TREE_CODE (pattern) == TEMPLATE_PARM_INDEX
4099 && ((TREE_CODE (parm_pack) == PARM_DECL
4100 && (TEMPLATE_PARM_DECL (pattern)
4101 == TEMPLATE_PARM_DECL (DECL_INITIAL (parm_pack))))
4102 || (TREE_CODE (parm_pack) == TEMPLATE_PARM_INDEX
4103 && (TEMPLATE_PARM_DECL (pattern)
4104 == TEMPLATE_PARM_DECL (parm_pack))))))
4105 && template_parameter_pack_p (pattern))
4111 /* Within the declaration of a template, return all levels of template
4112 parameters that apply. The template parameters are represented as
4113 a TREE_VEC, in the form documented in cp-tree.h for template
4117 current_template_args (void)
4120 tree args = NULL_TREE;
4121 int length = TMPL_PARMS_DEPTH (current_template_parms);
4124 /* If there is only one level of template parameters, we do not
4125 create a TREE_VEC of TREE_VECs. Instead, we return a single
4126 TREE_VEC containing the arguments. */
4128 args = make_tree_vec (length);
4130 for (header = current_template_parms; header; header = TREE_CHAIN (header))
4132 tree a = copy_node (TREE_VALUE (header));
4135 TREE_TYPE (a) = NULL_TREE;
4136 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
4137 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
4139 #ifdef ENABLE_CHECKING
4140 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
4144 TREE_VEC_ELT (args, --l) = a;
4149 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
4150 /* This can happen for template parms of a template template
4153 template<template<class T, class U> class TT> struct S;
4155 Consider the level of the parms of TT; T and U both have
4156 level 2; TT has no template parm of level 1. So in this case
4157 the first element of full_template_args is NULL_TREE. If we
4158 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
4159 of 2. This will make tsubst wrongly consider that T and U
4160 have level 1. Instead, let's create a dummy vector as the
4161 first element of full_template_args so that TMPL_ARG_DEPTH
4162 returns the correct depth for args. */
4163 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
4167 /* Update the declared TYPE by doing any lookups which were thought to be
4168 dependent, but are not now that we know the SCOPE of the declarator. */
4171 maybe_update_decl_type (tree orig_type, tree scope)
4173 tree type = orig_type;
4175 if (type == NULL_TREE)
4178 if (TREE_CODE (orig_type) == TYPE_DECL)
4179 type = TREE_TYPE (type);
4181 if (scope && TYPE_P (scope) && dependent_type_p (scope)
4182 && dependent_type_p (type)
4183 /* Don't bother building up the args in this case. */
4184 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
4186 /* tsubst in the args corresponding to the template parameters,
4187 including auto if present. Most things will be unchanged, but
4188 make_typename_type and tsubst_qualified_id will resolve
4189 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
4190 tree args = current_template_args ();
4191 tree auto_node = type_uses_auto (type);
4195 tree auto_vec = make_tree_vec (1);
4196 TREE_VEC_ELT (auto_vec, 0) = auto_node;
4197 args = add_to_template_args (args, auto_vec);
4199 pushed = push_scope (scope);
4200 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
4205 if (type == error_mark_node)
4208 if (TREE_CODE (orig_type) == TYPE_DECL)
4210 if (same_type_p (type, TREE_TYPE (orig_type)))
4213 type = TYPE_NAME (type);
4218 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
4219 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
4220 a member template. Used by push_template_decl below. */
4223 build_template_decl (tree decl, tree parms, bool member_template_p)
4225 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
4226 DECL_TEMPLATE_PARMS (tmpl) = parms;
4227 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
4228 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
4229 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
4234 struct template_parm_data
4236 /* The level of the template parameters we are currently
4240 /* The index of the specialization argument we are currently
4244 /* An array whose size is the number of template parameters. The
4245 elements are nonzero if the parameter has been used in any one
4246 of the arguments processed so far. */
4249 /* An array whose size is the number of template arguments. The
4250 elements are nonzero if the argument makes use of template
4251 parameters of this level. */
4252 int* arg_uses_template_parms;
4255 /* Subroutine of push_template_decl used to see if each template
4256 parameter in a partial specialization is used in the explicit
4257 argument list. If T is of the LEVEL given in DATA (which is
4258 treated as a template_parm_data*), then DATA->PARMS is marked
4262 mark_template_parm (tree t, void* data)
4266 struct template_parm_data* tpd = (struct template_parm_data*) data;
4268 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4270 level = TEMPLATE_PARM_LEVEL (t);
4271 idx = TEMPLATE_PARM_IDX (t);
4275 level = TEMPLATE_TYPE_LEVEL (t);
4276 idx = TEMPLATE_TYPE_IDX (t);
4279 if (level == tpd->level)
4281 tpd->parms[idx] = 1;
4282 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4285 /* Return zero so that for_each_template_parm will continue the
4286 traversal of the tree; we want to mark *every* template parm. */
4290 /* Process the partial specialization DECL. */
4293 process_partial_specialization (tree decl)
4295 tree type = TREE_TYPE (decl);
4296 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4297 tree specargs = CLASSTYPE_TI_ARGS (type);
4298 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4299 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4302 int nargs = TREE_VEC_LENGTH (inner_args);
4305 bool did_error_intro = false;
4306 struct template_parm_data tpd;
4307 struct template_parm_data tpd2;
4309 gcc_assert (current_template_parms);
4311 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4312 ntparms = TREE_VEC_LENGTH (inner_parms);
4314 /* We check that each of the template parameters given in the
4315 partial specialization is used in the argument list to the
4316 specialization. For example:
4318 template <class T> struct S;
4319 template <class T> struct S<T*>;
4321 The second declaration is OK because `T*' uses the template
4322 parameter T, whereas
4324 template <class T> struct S<int>;
4326 is no good. Even trickier is:
4337 The S2<T> declaration is actually invalid; it is a
4338 full-specialization. Of course,
4341 struct S2<T (*)(U)>;
4343 or some such would have been OK. */
4344 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4345 tpd.parms = XALLOCAVEC (int, ntparms);
4346 memset (tpd.parms, 0, sizeof (int) * ntparms);
4348 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4349 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4350 for (i = 0; i < nargs; ++i)
4352 tpd.current_arg = i;
4353 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4354 &mark_template_parm,
4357 /*include_nondeduced_p=*/false);
4359 for (i = 0; i < ntparms; ++i)
4360 if (tpd.parms[i] == 0)
4362 /* One of the template parms was not used in the
4364 if (!did_error_intro)
4366 error ("template parameters not used in partial specialization:");
4367 did_error_intro = true;
4370 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4373 if (did_error_intro)
4374 return error_mark_node;
4376 /* [temp.class.spec]
4378 The argument list of the specialization shall not be identical to
4379 the implicit argument list of the primary template. */
4380 if (comp_template_args
4382 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4384 error ("partial specialization %qT does not specialize any template arguments", type);
4386 /* [temp.class.spec]
4388 A partially specialized non-type argument expression shall not
4389 involve template parameters of the partial specialization except
4390 when the argument expression is a simple identifier.
4392 The type of a template parameter corresponding to a specialized
4393 non-type argument shall not be dependent on a parameter of the
4396 Also, we verify that pack expansions only occur at the
4397 end of the argument list. */
4398 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4400 for (i = 0; i < nargs; ++i)
4402 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4403 tree arg = TREE_VEC_ELT (inner_args, i);
4404 tree packed_args = NULL_TREE;
4407 if (ARGUMENT_PACK_P (arg))
4409 /* Extract the arguments from the argument pack. We'll be
4410 iterating over these in the following loop. */
4411 packed_args = ARGUMENT_PACK_ARGS (arg);
4412 len = TREE_VEC_LENGTH (packed_args);
4415 for (j = 0; j < len; j++)
4418 /* Get the Jth argument in the parameter pack. */
4419 arg = TREE_VEC_ELT (packed_args, j);
4421 if (PACK_EXPANSION_P (arg))
4423 /* Pack expansions must come at the end of the
4425 if ((packed_args && j < len - 1)
4426 || (!packed_args && i < nargs - 1))
4428 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4429 error ("parameter pack argument %qE must be at the "
4430 "end of the template argument list", arg);
4432 error ("parameter pack argument %qT must be at the "
4433 "end of the template argument list", arg);
4437 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4438 /* We only care about the pattern. */
4439 arg = PACK_EXPANSION_PATTERN (arg);
4441 if (/* These first two lines are the `non-type' bit. */
4443 && TREE_CODE (arg) != TEMPLATE_DECL
4444 /* This next line is the `argument expression is not just a
4445 simple identifier' condition and also the `specialized
4446 non-type argument' bit. */
4447 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4449 if ((!packed_args && tpd.arg_uses_template_parms[i])
4450 || (packed_args && uses_template_parms (arg)))
4451 error ("template argument %qE involves template parameter(s)",
4455 /* Look at the corresponding template parameter,
4456 marking which template parameters its type depends
4458 tree type = TREE_TYPE (parm);
4462 /* We haven't yet initialized TPD2. Do so now. */
4463 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4464 /* The number of parameters here is the number in the
4465 main template, which, as checked in the assertion
4467 tpd2.parms = XALLOCAVEC (int, nargs);
4469 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4472 /* Mark the template parameters. But this time, we're
4473 looking for the template parameters of the main
4474 template, not in the specialization. */
4475 tpd2.current_arg = i;
4476 tpd2.arg_uses_template_parms[i] = 0;
4477 memset (tpd2.parms, 0, sizeof (int) * nargs);
4478 for_each_template_parm (type,
4479 &mark_template_parm,
4482 /*include_nondeduced_p=*/false);
4484 if (tpd2.arg_uses_template_parms [i])
4486 /* The type depended on some template parameters.
4487 If they are fully specialized in the
4488 specialization, that's OK. */
4491 for (j = 0; j < nargs; ++j)
4492 if (tpd2.parms[j] != 0
4493 && tpd.arg_uses_template_parms [j])
4496 error_n (input_location, count,
4497 "type %qT of template argument %qE depends "
4498 "on a template parameter",
4499 "type %qT of template argument %qE depends "
4500 "on template parameters",
4509 /* We should only get here once. */
4510 gcc_assert (!COMPLETE_TYPE_P (type));
4512 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4513 = tree_cons (specargs, inner_parms,
4514 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4515 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4517 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4518 inst = TREE_CHAIN (inst))
4520 tree inst_type = TREE_VALUE (inst);
4521 if (COMPLETE_TYPE_P (inst_type)
4522 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4524 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4525 if (spec && TREE_TYPE (spec) == type)
4526 permerror (input_location,
4527 "partial specialization of %qT after instantiation "
4528 "of %qT", type, inst_type);
4535 /* Check that a template declaration's use of default arguments and
4536 parameter packs is not invalid. Here, PARMS are the template
4537 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4538 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4542 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4543 declaration (but not a definition); 1 indicates a declaration, 2
4544 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4545 emitted for extraneous default arguments.
4547 Returns TRUE if there were no errors found, FALSE otherwise. */
4550 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4551 int is_partial, int is_friend_decl)
4554 int last_level_to_check;
4556 bool no_errors = true;
4560 A default template-argument shall not be specified in a
4561 function template declaration or a function template definition, nor
4562 in the template-parameter-list of the definition of a member of a
4565 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4566 /* You can't have a function template declaration in a local
4567 scope, nor you can you define a member of a class template in a
4571 if (current_class_type
4572 && !TYPE_BEING_DEFINED (current_class_type)
4573 && DECL_LANG_SPECIFIC (decl)
4574 && DECL_DECLARES_FUNCTION_P (decl)
4575 /* If this is either a friend defined in the scope of the class
4576 or a member function. */
4577 && (DECL_FUNCTION_MEMBER_P (decl)
4578 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4579 : DECL_FRIEND_CONTEXT (decl)
4580 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4582 /* And, if it was a member function, it really was defined in
4583 the scope of the class. */
4584 && (!DECL_FUNCTION_MEMBER_P (decl)
4585 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4586 /* We already checked these parameters when the template was
4587 declared, so there's no need to do it again now. This function
4588 was defined in class scope, but we're processing it's body now
4589 that the class is complete. */
4592 /* Core issue 226 (C++0x only): the following only applies to class
4594 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4598 If a template-parameter has a default template-argument, all
4599 subsequent template-parameters shall have a default
4600 template-argument supplied. */
4601 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4603 tree inner_parms = TREE_VALUE (parm_level);
4604 int ntparms = TREE_VEC_LENGTH (inner_parms);
4605 int seen_def_arg_p = 0;
4608 for (i = 0; i < ntparms; ++i)
4610 tree parm = TREE_VEC_ELT (inner_parms, i);
4612 if (parm == error_mark_node)
4615 if (TREE_PURPOSE (parm))
4617 else if (seen_def_arg_p
4618 && !template_parameter_pack_p (TREE_VALUE (parm)))
4620 error ("no default argument for %qD", TREE_VALUE (parm));
4621 /* For better subsequent error-recovery, we indicate that
4622 there should have been a default argument. */
4623 TREE_PURPOSE (parm) = error_mark_node;
4629 /* Don't complain about an enclosing partial
4631 && parm_level == parms
4632 && TREE_CODE (decl) == TYPE_DECL
4634 && template_parameter_pack_p (TREE_VALUE (parm)))
4636 /* A primary class template can only have one
4637 parameter pack, at the end of the template
4640 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4641 error ("parameter pack %qE must be at the end of the"
4642 " template parameter list", TREE_VALUE (parm));
4644 error ("parameter pack %qT must be at the end of the"
4645 " template parameter list",
4646 TREE_TYPE (TREE_VALUE (parm)));
4648 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4656 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4660 /* For an ordinary class template, default template arguments are
4661 allowed at the innermost level, e.g.:
4662 template <class T = int>
4664 but, in a partial specialization, they're not allowed even
4665 there, as we have in [temp.class.spec]:
4667 The template parameter list of a specialization shall not
4668 contain default template argument values.
4670 So, for a partial specialization, or for a function template
4671 (in C++98/C++03), we look at all of them. */
4674 /* But, for a primary class template that is not a partial
4675 specialization we look at all template parameters except the
4677 parms = TREE_CHAIN (parms);
4679 /* Figure out what error message to issue. */
4680 if (is_friend_decl == 2)
4681 msg = G_("default template arguments may not be used in function template "
4682 "friend re-declaration");
4683 else if (is_friend_decl)
4684 msg = G_("default template arguments may not be used in function template "
4685 "friend declarations");
4686 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4687 msg = G_("default template arguments may not be used in function templates "
4688 "without -std=c++11 or -std=gnu++11");
4689 else if (is_partial)
4690 msg = G_("default template arguments may not be used in "
4691 "partial specializations");
4693 msg = G_("default argument for template parameter for class enclosing %qD");
4695 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4696 /* If we're inside a class definition, there's no need to
4697 examine the parameters to the class itself. On the one
4698 hand, they will be checked when the class is defined, and,
4699 on the other, default arguments are valid in things like:
4700 template <class T = double>
4701 struct S { template <class U> void f(U); };
4702 Here the default argument for `S' has no bearing on the
4703 declaration of `f'. */
4704 last_level_to_check = template_class_depth (current_class_type) + 1;
4706 /* Check everything. */
4707 last_level_to_check = 0;
4709 for (parm_level = parms;
4710 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4711 parm_level = TREE_CHAIN (parm_level))
4713 tree inner_parms = TREE_VALUE (parm_level);
4717 ntparms = TREE_VEC_LENGTH (inner_parms);
4718 for (i = 0; i < ntparms; ++i)
4720 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4723 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4728 if (is_friend_decl == 2)
4735 /* Clear out the default argument so that we are not
4737 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4741 /* At this point, if we're still interested in issuing messages,
4742 they must apply to classes surrounding the object declared. */
4744 msg = G_("default argument for template parameter for class "
4751 /* Worker for push_template_decl_real, called via
4752 for_each_template_parm. DATA is really an int, indicating the
4753 level of the parameters we are interested in. If T is a template
4754 parameter of that level, return nonzero. */
4757 template_parm_this_level_p (tree t, void* data)
4759 int this_level = *(int *)data;
4762 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4763 level = TEMPLATE_PARM_LEVEL (t);
4765 level = TEMPLATE_TYPE_LEVEL (t);
4766 return level == this_level;
4769 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4770 parameters given by current_template_args, or reuses a
4771 previously existing one, if appropriate. Returns the DECL, or an
4772 equivalent one, if it is replaced via a call to duplicate_decls.
4774 If IS_FRIEND is true, DECL is a friend declaration. */
4777 push_template_decl_real (tree decl, bool is_friend)
4785 int new_template_p = 0;
4786 /* True if the template is a member template, in the sense of
4788 bool member_template_p = false;
4790 if (decl == error_mark_node || !current_template_parms)
4791 return error_mark_node;
4793 /* See if this is a partial specialization. */
4794 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4795 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4796 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4798 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4802 /* For a friend, we want the context of the friend function, not
4803 the type of which it is a friend. */
4804 ctx = CP_DECL_CONTEXT (decl);
4805 else if (CP_DECL_CONTEXT (decl)
4806 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4807 /* In the case of a virtual function, we want the class in which
4809 ctx = CP_DECL_CONTEXT (decl);
4811 /* Otherwise, if we're currently defining some class, the DECL
4812 is assumed to be a member of the class. */
4813 ctx = current_scope ();
4815 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4818 if (!DECL_CONTEXT (decl))
4819 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4821 /* See if this is a primary template. */
4822 if (is_friend && ctx)
4823 /* A friend template that specifies a class context, i.e.
4824 template <typename T> friend void A<T>::f();
4828 primary = template_parm_scope_p ();
4832 if (DECL_CLASS_SCOPE_P (decl))
4833 member_template_p = true;
4834 if (TREE_CODE (decl) == TYPE_DECL
4835 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4837 error ("template class without a name");
4838 return error_mark_node;
4840 else if (TREE_CODE (decl) == FUNCTION_DECL)
4842 if (DECL_DESTRUCTOR_P (decl))
4846 A destructor shall not be a member template. */
4847 error ("destructor %qD declared as member template", decl);
4848 return error_mark_node;
4850 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4851 && (!prototype_p (TREE_TYPE (decl))
4852 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4853 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4854 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4855 == void_list_node)))
4857 /* [basic.stc.dynamic.allocation]
4859 An allocation function can be a function
4860 template. ... Template allocation functions shall
4861 have two or more parameters. */
4862 error ("invalid template declaration of %qD", decl);
4863 return error_mark_node;
4866 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4867 && CLASS_TYPE_P (TREE_TYPE (decl)))
4869 else if (TREE_CODE (decl) == TYPE_DECL
4870 && TYPE_DECL_ALIAS_P (decl))
4871 /* alias-declaration */
4872 gcc_assert (!DECL_ARTIFICIAL (decl));
4875 error ("template declaration of %q#D", decl);
4876 return error_mark_node;
4880 /* Check to see that the rules regarding the use of default
4881 arguments are not being violated. */
4882 check_default_tmpl_args (decl, current_template_parms,
4883 primary, is_partial, /*is_friend_decl=*/0);
4885 /* Ensure that there are no parameter packs in the type of this
4886 declaration that have not been expanded. */
4887 if (TREE_CODE (decl) == FUNCTION_DECL)
4889 /* Check each of the arguments individually to see if there are
4890 any bare parameter packs. */
4891 tree type = TREE_TYPE (decl);
4892 tree arg = DECL_ARGUMENTS (decl);
4893 tree argtype = TYPE_ARG_TYPES (type);
4895 while (arg && argtype)
4897 if (!FUNCTION_PARAMETER_PACK_P (arg)
4898 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4900 /* This is a PARM_DECL that contains unexpanded parameter
4901 packs. We have already complained about this in the
4902 check_for_bare_parameter_packs call, so just replace
4903 these types with ERROR_MARK_NODE. */
4904 TREE_TYPE (arg) = error_mark_node;
4905 TREE_VALUE (argtype) = error_mark_node;
4908 arg = DECL_CHAIN (arg);
4909 argtype = TREE_CHAIN (argtype);
4912 /* Check for bare parameter packs in the return type and the
4913 exception specifiers. */
4914 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4915 /* Errors were already issued, set return type to int
4916 as the frontend doesn't expect error_mark_node as
4918 TREE_TYPE (type) = integer_type_node;
4919 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4920 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4922 else if (check_for_bare_parameter_packs ((TREE_CODE (decl) == TYPE_DECL
4923 && TYPE_DECL_ALIAS_P (decl))
4924 ? DECL_ORIGINAL_TYPE (decl)
4925 : TREE_TYPE (decl)))
4927 TREE_TYPE (decl) = error_mark_node;
4928 return error_mark_node;
4932 return process_partial_specialization (decl);
4934 args = current_template_args ();
4937 || TREE_CODE (ctx) == FUNCTION_DECL
4938 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4939 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4941 if (DECL_LANG_SPECIFIC (decl)
4942 && DECL_TEMPLATE_INFO (decl)
4943 && DECL_TI_TEMPLATE (decl))
4944 tmpl = DECL_TI_TEMPLATE (decl);
4945 /* If DECL is a TYPE_DECL for a class-template, then there won't
4946 be DECL_LANG_SPECIFIC. The information equivalent to
4947 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4948 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4949 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4950 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4952 /* Since a template declaration already existed for this
4953 class-type, we must be redeclaring it here. Make sure
4954 that the redeclaration is valid. */
4955 redeclare_class_template (TREE_TYPE (decl),
4956 current_template_parms);
4957 /* We don't need to create a new TEMPLATE_DECL; just use the
4958 one we already had. */
4959 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4963 tmpl = build_template_decl (decl, current_template_parms,
4967 if (DECL_LANG_SPECIFIC (decl)
4968 && DECL_TEMPLATE_SPECIALIZATION (decl))
4970 /* A specialization of a member template of a template
4972 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4973 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4974 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4980 tree a, t, current, parms;
4982 tree tinfo = get_template_info (decl);
4986 error ("template definition of non-template %q#D", decl);
4987 return error_mark_node;
4990 tmpl = TI_TEMPLATE (tinfo);
4992 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4993 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4994 && DECL_TEMPLATE_SPECIALIZATION (decl)
4995 && DECL_MEMBER_TEMPLATE_P (tmpl))
4999 /* The declaration is a specialization of a member
5000 template, declared outside the class. Therefore, the
5001 innermost template arguments will be NULL, so we
5002 replace them with the arguments determined by the
5003 earlier call to check_explicit_specialization. */
5004 args = DECL_TI_ARGS (decl);
5007 = build_template_decl (decl, current_template_parms,
5009 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
5010 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
5011 DECL_TI_TEMPLATE (decl) = new_tmpl;
5012 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
5013 DECL_TEMPLATE_INFO (new_tmpl)
5014 = build_template_info (tmpl, args);
5016 register_specialization (new_tmpl,
5017 most_general_template (tmpl),
5023 /* Make sure the template headers we got make sense. */
5025 parms = DECL_TEMPLATE_PARMS (tmpl);
5026 i = TMPL_PARMS_DEPTH (parms);
5027 if (TMPL_ARGS_DEPTH (args) != i)
5029 error ("expected %d levels of template parms for %q#D, got %d",
5030 i, decl, TMPL_ARGS_DEPTH (args));
5033 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
5035 a = TMPL_ARGS_LEVEL (args, i);
5036 t = INNERMOST_TEMPLATE_PARMS (parms);
5038 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
5040 if (current == decl)
5041 error ("got %d template parameters for %q#D",
5042 TREE_VEC_LENGTH (a), decl);
5044 error ("got %d template parameters for %q#T",
5045 TREE_VEC_LENGTH (a), current);
5046 error (" but %d required", TREE_VEC_LENGTH (t));
5047 return error_mark_node;
5050 if (current == decl)
5052 else if (current == NULL_TREE)
5053 /* Can happen in erroneous input. */
5056 current = (TYPE_P (current)
5057 ? TYPE_CONTEXT (current)
5058 : DECL_CONTEXT (current));
5061 /* Check that the parms are used in the appropriate qualifying scopes
5062 in the declarator. */
5063 if (!comp_template_args
5065 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
5068 template arguments to %qD do not match original template %qD",
5069 decl, DECL_TEMPLATE_RESULT (tmpl));
5070 if (!uses_template_parms (TI_ARGS (tinfo)))
5071 inform (input_location, "use template<> for an explicit specialization");
5072 /* Avoid crash in import_export_decl. */
5073 DECL_INTERFACE_KNOWN (decl) = 1;
5074 return error_mark_node;
5078 DECL_TEMPLATE_RESULT (tmpl) = decl;
5079 TREE_TYPE (tmpl) = TREE_TYPE (decl);
5081 /* Push template declarations for global functions and types. Note
5082 that we do not try to push a global template friend declared in a
5083 template class; such a thing may well depend on the template
5084 parameters of the class. */
5085 if (new_template_p && !ctx
5086 && !(is_friend && template_class_depth (current_class_type) > 0))
5088 tmpl = pushdecl_namespace_level (tmpl, is_friend);
5089 if (tmpl == error_mark_node)
5090 return error_mark_node;
5092 /* Hide template friend classes that haven't been declared yet. */
5093 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
5095 DECL_ANTICIPATED (tmpl) = 1;
5096 DECL_FRIEND_P (tmpl) = 1;
5102 tree parms = DECL_TEMPLATE_PARMS (tmpl);
5105 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
5106 if (DECL_CONV_FN_P (tmpl))
5108 int depth = TMPL_PARMS_DEPTH (parms);
5110 /* It is a conversion operator. See if the type converted to
5111 depends on innermost template operands. */
5113 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
5115 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
5118 /* Give template template parms a DECL_CONTEXT of the template
5119 for which they are a parameter. */
5120 parms = INNERMOST_TEMPLATE_PARMS (parms);
5121 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
5123 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5124 if (TREE_CODE (parm) == TEMPLATE_DECL)
5125 DECL_CONTEXT (parm) = tmpl;
5129 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
5130 back to its most general template. If TMPL is a specialization,
5131 ARGS may only have the innermost set of arguments. Add the missing
5132 argument levels if necessary. */
5133 if (DECL_TEMPLATE_INFO (tmpl))
5134 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
5136 info = build_template_info (tmpl, args);
5138 if (DECL_IMPLICIT_TYPEDEF_P (decl))
5139 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
5142 if (primary && !DECL_LANG_SPECIFIC (decl))
5143 retrofit_lang_decl (decl);
5144 if (DECL_LANG_SPECIFIC (decl))
5145 DECL_TEMPLATE_INFO (decl) = info;
5148 return DECL_TEMPLATE_RESULT (tmpl);
5152 push_template_decl (tree decl)
5154 return push_template_decl_real (decl, false);
5157 /* Called when a class template TYPE is redeclared with the indicated
5158 template PARMS, e.g.:
5160 template <class T> struct S;
5161 template <class T> struct S {}; */
5164 redeclare_class_template (tree type, tree parms)
5170 if (!TYPE_TEMPLATE_INFO (type))
5172 error ("%qT is not a template type", type);
5176 tmpl = TYPE_TI_TEMPLATE (type);
5177 if (!PRIMARY_TEMPLATE_P (tmpl))
5178 /* The type is nested in some template class. Nothing to worry
5179 about here; there are no new template parameters for the nested
5185 error ("template specifiers not specified in declaration of %qD",
5190 parms = INNERMOST_TEMPLATE_PARMS (parms);
5191 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
5193 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
5195 error_n (input_location, TREE_VEC_LENGTH (parms),
5196 "redeclared with %d template parameter",
5197 "redeclared with %d template parameters",
5198 TREE_VEC_LENGTH (parms));
5199 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
5200 "previous declaration %q+D used %d template parameter",
5201 "previous declaration %q+D used %d template parameters",
5202 tmpl, TREE_VEC_LENGTH (tmpl_parms));
5206 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
5213 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
5214 || TREE_VEC_ELT (parms, i) == error_mark_node)
5217 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
5218 if (tmpl_parm == error_mark_node)
5221 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5222 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
5223 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
5225 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5227 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5228 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5229 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5230 || (TREE_CODE (tmpl_parm) != PARM_DECL
5231 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5232 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5233 || (TREE_CODE (tmpl_parm) == PARM_DECL
5234 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5235 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5237 error ("template parameter %q+#D", tmpl_parm);
5238 error ("redeclared here as %q#D", parm);
5242 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5244 /* We have in [temp.param]:
5246 A template-parameter may not be given default arguments
5247 by two different declarations in the same scope. */
5248 error_at (input_location, "redefinition of default argument for %q#D", parm);
5249 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5250 "original definition appeared here");
5254 if (parm_default != NULL_TREE)
5255 /* Update the previous template parameters (which are the ones
5256 that will really count) with the new default value. */
5257 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5258 else if (tmpl_default != NULL_TREE)
5259 /* Update the new parameters, too; they'll be used as the
5260 parameters for any members. */
5261 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5267 /* Simplify EXPR if it is a non-dependent expression. Returns the
5268 (possibly simplified) expression. */
5271 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5273 if (expr == NULL_TREE)
5276 /* If we're in a template, but EXPR isn't value dependent, simplify
5277 it. We're supposed to treat:
5279 template <typename T> void f(T[1 + 1]);
5280 template <typename T> void f(T[2]);
5282 as two declarations of the same function, for example. */
5283 if (processing_template_decl
5284 && !type_dependent_expression_p (expr)
5285 && potential_constant_expression (expr)
5286 && !value_dependent_expression_p (expr))
5288 HOST_WIDE_INT saved_processing_template_decl;
5290 saved_processing_template_decl = processing_template_decl;
5291 processing_template_decl = 0;
5292 expr = tsubst_copy_and_build (expr,
5295 /*in_decl=*/NULL_TREE,
5296 /*function_p=*/false,
5297 /*integral_constant_expression_p=*/true);
5298 processing_template_decl = saved_processing_template_decl;
5304 fold_non_dependent_expr (tree expr)
5306 return fold_non_dependent_expr_sfinae (expr, tf_error);
5309 /* Return TRUE iff T is a type alias, a TEMPLATE_DECL for an alias
5310 template declaration, or a TYPE_DECL for an alias declaration. */
5313 alias_type_or_template_p (tree t)
5317 return ((TREE_CODE (t) == TYPE_DECL && TYPE_DECL_ALIAS_P (t))
5320 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
5321 || DECL_ALIAS_TEMPLATE_P (t));
5324 /* Return TRUE iff is a specialization of an alias template. */
5327 alias_template_specialization_p (tree t)
5331 return (primary_template_instantiation_p (t)
5332 && DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (t)));
5335 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5336 must be a function or a pointer-to-function type, as specified
5337 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5338 and check that the resulting function has external linkage. */
5341 convert_nontype_argument_function (tree type, tree expr)
5345 linkage_kind linkage;
5347 fn = instantiate_type (type, fns, tf_none);
5348 if (fn == error_mark_node)
5349 return error_mark_node;
5352 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5353 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5354 if (BASELINK_P (fn_no_ptr))
5355 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5357 /* [temp.arg.nontype]/1
5359 A template-argument for a non-type, non-template template-parameter
5362 -- the address of an object or function with external [C++11: or
5363 internal] linkage. */
5364 linkage = decl_linkage (fn_no_ptr);
5365 if (cxx_dialect >= cxx0x ? linkage == lk_none : linkage != lk_external)
5367 if (cxx_dialect >= cxx0x)
5368 error ("%qE is not a valid template argument for type %qT "
5369 "because %qD has no linkage",
5370 expr, type, fn_no_ptr);
5372 error ("%qE is not a valid template argument for type %qT "
5373 "because %qD does not have external linkage",
5374 expr, type, fn_no_ptr);
5381 /* Subroutine of convert_nontype_argument.
5382 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5383 Emit an error otherwise. */
5386 check_valid_ptrmem_cst_expr (tree type, tree expr,
5387 tsubst_flags_t complain)
5390 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5392 if (cxx_dialect >= cxx0x && null_member_pointer_value_p (expr))
5394 if (complain & tf_error)
5396 error ("%qE is not a valid template argument for type %qT",
5398 error ("it must be a pointer-to-member of the form %<&X::Y%>");
5403 /* Returns TRUE iff the address of OP is value-dependent.
5405 14.6.2.4 [temp.dep.temp]:
5406 A non-integral non-type template-argument is dependent if its type is
5407 dependent or it has either of the following forms
5410 and contains a nested-name-specifier which specifies a class-name that
5411 names a dependent type.
5413 We generalize this to just say that the address of a member of a
5414 dependent class is value-dependent; the above doesn't cover the
5415 address of a static data member named with an unqualified-id. */
5418 has_value_dependent_address (tree op)
5420 /* We could use get_inner_reference here, but there's no need;
5421 this is only relevant for template non-type arguments, which
5422 can only be expressed as &id-expression. */
5425 tree ctx = CP_DECL_CONTEXT (op);
5426 if (TYPE_P (ctx) && dependent_type_p (ctx))
5433 /* The next set of functions are used for providing helpful explanatory
5434 diagnostics for failed overload resolution. Their messages should be
5435 indented by two spaces for consistency with the messages in
5439 unify_success (bool explain_p ATTRIBUTE_UNUSED)
5445 unify_parameter_deduction_failure (bool explain_p, tree parm)
5448 inform (input_location,
5449 " couldn't deduce template parameter %qD", parm);
5454 unify_invalid (bool explain_p ATTRIBUTE_UNUSED)
5460 unify_cv_qual_mismatch (bool explain_p, tree parm, tree arg)
5463 inform (input_location,
5464 " types %qT and %qT have incompatible cv-qualifiers",
5470 unify_type_mismatch (bool explain_p, tree parm, tree arg)
5473 inform (input_location, " mismatched types %qT and %qT", parm, arg);
5478 unify_parameter_pack_mismatch (bool explain_p, tree parm, tree arg)
5481 inform (input_location,
5482 " template parameter %qD is not a parameter pack, but "
5489 unify_ptrmem_cst_mismatch (bool explain_p, tree parm, tree arg)
5492 inform (input_location,
5493 " template argument %qE does not match "
5494 "pointer-to-member constant %qE",
5500 unify_expression_unequal (bool explain_p, tree parm, tree arg)
5503 inform (input_location, " %qE is not equivalent to %qE", parm, arg);
5508 unify_parameter_pack_inconsistent (bool explain_p, tree old_arg, tree new_arg)
5511 inform (input_location,
5512 " inconsistent parameter pack deduction with %qT and %qT",
5518 unify_inconsistency (bool explain_p, tree parm, tree first, tree second)
5523 inform (input_location,
5524 " deduced conflicting types for parameter %qT (%qT and %qT)",
5525 parm, first, second);
5527 inform (input_location,
5528 " deduced conflicting values for non-type parameter "
5529 "%qE (%qE and %qE)", parm, first, second);
5535 unify_vla_arg (bool explain_p, tree arg)
5538 inform (input_location,
5539 " variable-sized array type %qT is not "
5540 "a valid template argument",
5546 unify_method_type_error (bool explain_p, tree arg)
5549 inform (input_location,
5550 " member function type %qT is not a valid template argument",
5556 unify_arity (bool explain_p, int have, int wanted)
5559 inform_n (input_location, wanted,
5560 " candidate expects %d argument, %d provided",
5561 " candidate expects %d arguments, %d provided",
5567 unify_too_many_arguments (bool explain_p, int have, int wanted)
5569 return unify_arity (explain_p, have, wanted);
5573 unify_too_few_arguments (bool explain_p, int have, int wanted)
5575 return unify_arity (explain_p, have, wanted);
5579 unify_arg_conversion (bool explain_p, tree to_type,
5580 tree from_type, tree arg)
5583 inform (input_location, " cannot convert %qE (type %qT) to type %qT",
5584 arg, from_type, to_type);
5589 unify_no_common_base (bool explain_p, enum template_base_result r,
5590 tree parm, tree arg)
5595 case tbr_ambiguous_baseclass:
5596 inform (input_location, " %qT is an ambiguous base class of %qT",
5600 inform (input_location, " %qT is not derived from %qT", arg, parm);
5607 unify_inconsistent_template_template_parameters (bool explain_p)
5610 inform (input_location,
5611 " template parameters of a template template argument are "
5612 "inconsistent with other deduced template arguments");
5617 unify_template_deduction_failure (bool explain_p, tree parm, tree arg)
5620 inform (input_location,
5621 " can't deduce a template for %qT from non-template type %qT",
5627 unify_template_argument_mismatch (bool explain_p, tree parm, tree arg)
5630 inform (input_location,
5631 " template argument %qE does not match %qD", arg, parm);
5636 unify_overload_resolution_failure (bool explain_p, tree arg)
5639 inform (input_location,
5640 " could not resolve address from overloaded function %qE",
5645 /* Attempt to convert the non-type template parameter EXPR to the
5646 indicated TYPE. If the conversion is successful, return the
5647 converted value. If the conversion is unsuccessful, return
5648 NULL_TREE if we issued an error message, or error_mark_node if we
5649 did not. We issue error messages for out-and-out bad template
5650 parameters, but not simply because the conversion failed, since we
5651 might be just trying to do argument deduction. Both TYPE and EXPR
5652 must be non-dependent.
5654 The conversion follows the special rules described in
5655 [temp.arg.nontype], and it is much more strict than an implicit
5658 This function is called twice for each template argument (see
5659 lookup_template_class for a more accurate description of this
5660 problem). This means that we need to handle expressions which
5661 are not valid in a C++ source, but can be created from the
5662 first call (for instance, casts to perform conversions). These
5663 hacks can go away after we fix the double coercion problem. */
5666 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5670 /* Detect immediately string literals as invalid non-type argument.
5671 This special-case is not needed for correctness (we would easily
5672 catch this later), but only to provide better diagnostic for this
5673 common user mistake. As suggested by DR 100, we do not mention
5674 linkage issues in the diagnostic as this is not the point. */
5675 /* FIXME we're making this OK. */
5676 if (TREE_CODE (expr) == STRING_CST)
5678 if (complain & tf_error)
5679 error ("%qE is not a valid template argument for type %qT "
5680 "because string literals can never be used in this context",
5685 /* Add the ADDR_EXPR now for the benefit of
5686 value_dependent_expression_p. */
5687 if (TYPE_PTROBV_P (type)
5688 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE)
5689 expr = decay_conversion (expr);
5691 /* If we are in a template, EXPR may be non-dependent, but still
5692 have a syntactic, rather than semantic, form. For example, EXPR
5693 might be a SCOPE_REF, rather than the VAR_DECL to which the
5694 SCOPE_REF refers. Preserving the qualifying scope is necessary
5695 so that access checking can be performed when the template is
5696 instantiated -- but here we need the resolved form so that we can
5697 convert the argument. */
5698 if (TYPE_REF_OBJ_P (type)
5699 && has_value_dependent_address (expr))
5700 /* If we want the address and it's value-dependent, don't fold. */;
5701 else if (!type_unknown_p (expr))
5702 expr = fold_non_dependent_expr_sfinae (expr, complain);
5703 if (error_operand_p (expr))
5704 return error_mark_node;
5705 expr_type = TREE_TYPE (expr);
5706 if (TREE_CODE (type) == REFERENCE_TYPE)
5707 expr = mark_lvalue_use (expr);
5709 expr = mark_rvalue_use (expr);
5711 /* 14.3.2/5: The null pointer{,-to-member} conversion is applied
5712 to a non-type argument of "nullptr". */
5713 if (expr == nullptr_node
5714 && (TYPE_PTR_P (type) || TYPE_PTR_TO_MEMBER_P (type)))
5715 expr = convert (type, expr);
5717 /* In C++11, integral or enumeration non-type template arguments can be
5718 arbitrary constant expressions. Pointer and pointer to
5719 member arguments can be general constant expressions that evaluate
5720 to a null value, but otherwise still need to be of a specific form. */
5721 if (cxx_dialect >= cxx0x)
5723 if (TREE_CODE (expr) == PTRMEM_CST)
5724 /* A PTRMEM_CST is already constant, and a valid template
5725 argument for a parameter of pointer to member type, we just want
5726 to leave it in that form rather than lower it to a
5728 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5729 expr = maybe_constant_value (expr);
5730 else if (TYPE_PTR_P (type)
5731 || TYPE_PTR_TO_MEMBER_P (type))
5733 tree folded = maybe_constant_value (expr);
5734 if (TYPE_PTR_P (type) ? integer_zerop (folded)
5735 : null_member_pointer_value_p (folded))
5740 /* HACK: Due to double coercion, we can get a
5741 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5742 which is the tree that we built on the first call (see
5743 below when coercing to reference to object or to reference to
5744 function). We just strip everything and get to the arg.
5745 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5747 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5749 tree probe_type, probe = expr;
5750 if (REFERENCE_REF_P (probe))
5751 probe = TREE_OPERAND (probe, 0);
5752 probe_type = TREE_TYPE (probe);
5753 if (TREE_CODE (probe) == NOP_EXPR)
5755 /* ??? Maybe we could use convert_from_reference here, but we
5756 would need to relax its constraints because the NOP_EXPR
5757 could actually change the type to something more cv-qualified,
5758 and this is not folded by convert_from_reference. */
5759 tree addr = TREE_OPERAND (probe, 0);
5760 gcc_assert (TREE_CODE (probe_type) == REFERENCE_TYPE);
5761 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5762 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5763 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5764 (TREE_TYPE (probe_type),
5765 TREE_TYPE (TREE_TYPE (addr))));
5767 expr = TREE_OPERAND (addr, 0);
5768 expr_type = TREE_TYPE (expr);
5772 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5773 parameter is a pointer to object, through decay and
5774 qualification conversion. Let's strip everything. */
5775 else if (TREE_CODE (expr) == NOP_EXPR && TYPE_PTROBV_P (type))
5778 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5779 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5780 /* Skip the ADDR_EXPR only if it is part of the decay for
5781 an array. Otherwise, it is part of the original argument
5782 in the source code. */
5783 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5784 expr = TREE_OPERAND (expr, 0);
5785 expr_type = TREE_TYPE (expr);
5788 /* [temp.arg.nontype]/5, bullet 1
5790 For a non-type template-parameter of integral or enumeration type,
5791 integral promotions (_conv.prom_) and integral conversions
5792 (_conv.integral_) are applied. */
5793 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5795 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5796 t = maybe_constant_value (t);
5797 if (t != error_mark_node)
5800 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5801 return error_mark_node;
5803 /* Notice that there are constant expressions like '4 % 0' which
5804 do not fold into integer constants. */
5805 if (TREE_CODE (expr) != INTEGER_CST)
5807 if (complain & tf_error)
5809 int errs = errorcount, warns = warningcount;
5810 if (processing_template_decl
5811 && !require_potential_constant_expression (expr))
5813 expr = cxx_constant_value (expr);
5814 if (errorcount > errs || warningcount > warns)
5815 inform (EXPR_LOC_OR_HERE (expr),
5816 "in template argument for type %qT ", type);
5817 if (expr == error_mark_node)
5819 /* else cxx_constant_value complained but gave us
5820 a real constant, so go ahead. */
5821 gcc_assert (TREE_CODE (expr) == INTEGER_CST);
5827 /* [temp.arg.nontype]/5, bullet 2
5829 For a non-type template-parameter of type pointer to object,
5830 qualification conversions (_conv.qual_) and the array-to-pointer
5831 conversion (_conv.array_) are applied. */
5832 else if (TYPE_PTROBV_P (type))
5834 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5836 A template-argument for a non-type, non-template template-parameter
5837 shall be one of: [...]
5839 -- the name of a non-type template-parameter;
5840 -- the address of an object or function with external linkage, [...]
5841 expressed as "& id-expression" where the & is optional if the name
5842 refers to a function or array, or if the corresponding
5843 template-parameter is a reference.
5845 Here, we do not care about functions, as they are invalid anyway
5846 for a parameter of type pointer-to-object. */
5848 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5849 /* Non-type template parameters are OK. */
5851 else if (cxx_dialect >= cxx0x && integer_zerop (expr))
5852 /* Null pointer values are OK in C++11. */;
5853 else if (TREE_CODE (expr) != ADDR_EXPR
5854 && TREE_CODE (expr_type) != ARRAY_TYPE)
5856 if (TREE_CODE (expr) == VAR_DECL)
5858 error ("%qD is not a valid template argument "
5859 "because %qD is a variable, not the address of "
5864 /* Other values, like integer constants, might be valid
5865 non-type arguments of some other type. */
5866 return error_mark_node;
5872 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5873 ? TREE_OPERAND (expr, 0) : expr);
5874 if (TREE_CODE (decl) != VAR_DECL)
5876 error ("%qE is not a valid template argument of type %qT "
5877 "because %qE is not a variable",
5881 else if (cxx_dialect < cxx0x && !DECL_EXTERNAL_LINKAGE_P (decl))
5883 error ("%qE is not a valid template argument of type %qT "
5884 "because %qD does not have external linkage",
5888 else if (cxx_dialect >= cxx0x && decl_linkage (decl) == lk_none)
5890 error ("%qE is not a valid template argument of type %qT "
5891 "because %qD has no linkage",
5897 expr = decay_conversion (expr);
5898 if (expr == error_mark_node)
5899 return error_mark_node;
5901 expr = perform_qualification_conversions (type, expr);
5902 if (expr == error_mark_node)
5903 return error_mark_node;
5905 /* [temp.arg.nontype]/5, bullet 3
5907 For a non-type template-parameter of type reference to object, no
5908 conversions apply. The type referred to by the reference may be more
5909 cv-qualified than the (otherwise identical) type of the
5910 template-argument. The template-parameter is bound directly to the
5911 template-argument, which must be an lvalue. */
5912 else if (TYPE_REF_OBJ_P (type))
5914 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5916 return error_mark_node;
5918 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5920 error ("%qE is not a valid template argument for type %qT "
5921 "because of conflicts in cv-qualification", expr, type);
5925 if (!real_lvalue_p (expr))
5927 error ("%qE is not a valid template argument for type %qT "
5928 "because it is not an lvalue", expr, type);
5932 /* [temp.arg.nontype]/1
5934 A template-argument for a non-type, non-template template-parameter
5935 shall be one of: [...]
5937 -- the address of an object or function with external linkage. */
5938 if (TREE_CODE (expr) == INDIRECT_REF
5939 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5941 expr = TREE_OPERAND (expr, 0);
5944 error ("%q#D is not a valid template argument for type %qT "
5945 "because a reference variable does not have a constant "
5946 "address", expr, type);
5953 error ("%qE is not a valid template argument for type %qT "
5954 "because it is not an object with external linkage",
5959 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5961 error ("%qE is not a valid template argument for type %qT "
5962 "because object %qD has not external linkage",
5967 expr = build_nop (type, build_address (expr));
5969 /* [temp.arg.nontype]/5, bullet 4
5971 For a non-type template-parameter of type pointer to function, only
5972 the function-to-pointer conversion (_conv.func_) is applied. If the
5973 template-argument represents a set of overloaded functions (or a
5974 pointer to such), the matching function is selected from the set
5976 else if (TYPE_PTRFN_P (type))
5978 /* If the argument is a template-id, we might not have enough
5979 context information to decay the pointer. */
5980 if (!type_unknown_p (expr_type))
5982 expr = decay_conversion (expr);
5983 if (expr == error_mark_node)
5984 return error_mark_node;
5987 if (cxx_dialect >= cxx0x && integer_zerop (expr))
5988 /* Null pointer values are OK in C++11. */
5989 return perform_qualification_conversions (type, expr);
5991 expr = convert_nontype_argument_function (type, expr);
5992 if (!expr || expr == error_mark_node)
5995 if (TREE_CODE (expr) != ADDR_EXPR)
5997 error ("%qE is not a valid template argument for type %qT", expr, type);
5998 error ("it must be the address of a function with external linkage");
6002 /* [temp.arg.nontype]/5, bullet 5
6004 For a non-type template-parameter of type reference to function, no
6005 conversions apply. If the template-argument represents a set of
6006 overloaded functions, the matching function is selected from the set
6008 else if (TYPE_REFFN_P (type))
6010 if (TREE_CODE (expr) == ADDR_EXPR)
6012 error ("%qE is not a valid template argument for type %qT "
6013 "because it is a pointer", expr, type);
6014 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
6018 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
6019 if (!expr || expr == error_mark_node)
6022 expr = build_nop (type, build_address (expr));
6024 /* [temp.arg.nontype]/5, bullet 6
6026 For a non-type template-parameter of type pointer to member function,
6027 no conversions apply. If the template-argument represents a set of
6028 overloaded member functions, the matching member function is selected
6029 from the set (_over.over_). */
6030 else if (TYPE_PTRMEMFUNC_P (type))
6032 expr = instantiate_type (type, expr, tf_none);
6033 if (expr == error_mark_node)
6034 return error_mark_node;
6036 /* [temp.arg.nontype] bullet 1 says the pointer to member
6037 expression must be a pointer-to-member constant. */
6038 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
6039 return error_mark_node;
6041 /* There is no way to disable standard conversions in
6042 resolve_address_of_overloaded_function (called by
6043 instantiate_type). It is possible that the call succeeded by
6044 converting &B::I to &D::I (where B is a base of D), so we need
6045 to reject this conversion here.
6047 Actually, even if there was a way to disable standard conversions,
6048 it would still be better to reject them here so that we can
6049 provide a superior diagnostic. */
6050 if (!same_type_p (TREE_TYPE (expr), type))
6052 error ("%qE is not a valid template argument for type %qT "
6053 "because it is of type %qT", expr, type,
6055 /* If we are just one standard conversion off, explain. */
6056 if (can_convert (type, TREE_TYPE (expr)))
6057 inform (input_location,
6058 "standard conversions are not allowed in this context");
6062 /* [temp.arg.nontype]/5, bullet 7
6064 For a non-type template-parameter of type pointer to data member,
6065 qualification conversions (_conv.qual_) are applied. */
6066 else if (TYPE_PTRMEM_P (type))
6068 /* [temp.arg.nontype] bullet 1 says the pointer to member
6069 expression must be a pointer-to-member constant. */
6070 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
6071 return error_mark_node;
6073 expr = perform_qualification_conversions (type, expr);
6074 if (expr == error_mark_node)
6077 else if (NULLPTR_TYPE_P (type))
6079 if (expr != nullptr_node)
6081 error ("%qE is not a valid template argument for type %qT "
6082 "because it is of type %qT", expr, type, TREE_TYPE (expr));
6087 /* A template non-type parameter must be one of the above. */
6091 /* Sanity check: did we actually convert the argument to the
6093 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6094 (type, TREE_TYPE (expr)));
6098 /* Subroutine of coerce_template_template_parms, which returns 1 if
6099 PARM_PARM and ARG_PARM match using the rule for the template
6100 parameters of template template parameters. Both PARM and ARG are
6101 template parameters; the rest of the arguments are the same as for
6102 coerce_template_template_parms.
6105 coerce_template_template_parm (tree parm,
6107 tsubst_flags_t complain,
6111 if (arg == NULL_TREE || arg == error_mark_node
6112 || parm == NULL_TREE || parm == error_mark_node)
6115 if (TREE_CODE (arg) != TREE_CODE (parm))
6118 switch (TREE_CODE (parm))
6121 /* We encounter instantiations of templates like
6122 template <template <template <class> class> class TT>
6125 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6126 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6128 if (!coerce_template_template_parms
6129 (parmparm, argparm, complain, in_decl, outer_args))
6135 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
6136 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6137 /* Argument is a parameter pack but parameter is not. */
6142 /* The tsubst call is used to handle cases such as
6144 template <int> class C {};
6145 template <class T, template <T> class TT> class D {};
6148 i.e. the parameter list of TT depends on earlier parameters. */
6149 if (!uses_template_parms (TREE_TYPE (arg))
6151 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
6155 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
6156 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6157 /* Argument is a parameter pack but parameter is not. */
6170 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
6171 template template parameters. Both PARM_PARMS and ARG_PARMS are
6172 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
6175 Consider the example:
6176 template <class T> class A;
6177 template<template <class U> class TT> class B;
6179 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
6180 the parameters to A, and OUTER_ARGS contains A. */
6183 coerce_template_template_parms (tree parm_parms,
6185 tsubst_flags_t complain,
6189 int nparms, nargs, i;
6193 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
6194 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
6196 nparms = TREE_VEC_LENGTH (parm_parms);
6197 nargs = TREE_VEC_LENGTH (arg_parms);
6199 /* Determine whether we have a parameter pack at the end of the
6200 template template parameter's template parameter list. */
6201 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
6203 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
6205 if (parm == error_mark_node)
6208 switch (TREE_CODE (parm))
6212 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6217 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6227 && !(variadic_p && nargs >= nparms - 1))
6230 /* Check all of the template parameters except the parameter pack at
6231 the end (if any). */
6232 for (i = 0; i < nparms - variadic_p; ++i)
6234 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
6235 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6238 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6239 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6241 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6249 /* Check each of the template parameters in the template
6250 argument against the template parameter pack at the end of
6251 the template template parameter. */
6252 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
6255 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6257 for (; i < nargs; ++i)
6259 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6262 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6264 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6273 /* Verifies that the deduced template arguments (in TARGS) for the
6274 template template parameters (in TPARMS) represent valid bindings,
6275 by comparing the template parameter list of each template argument
6276 to the template parameter list of its corresponding template
6277 template parameter, in accordance with DR150. This
6278 routine can only be called after all template arguments have been
6279 deduced. It will return TRUE if all of the template template
6280 parameter bindings are okay, FALSE otherwise. */
6282 template_template_parm_bindings_ok_p (tree tparms, tree targs)
6284 int i, ntparms = TREE_VEC_LENGTH (tparms);
6287 /* We're dealing with template parms in this process. */
6288 ++processing_template_decl;
6290 targs = INNERMOST_TEMPLATE_ARGS (targs);
6292 for (i = 0; i < ntparms; ++i)
6294 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
6295 tree targ = TREE_VEC_ELT (targs, i);
6297 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
6299 tree packed_args = NULL_TREE;
6302 if (ARGUMENT_PACK_P (targ))
6304 /* Look inside the argument pack. */
6305 packed_args = ARGUMENT_PACK_ARGS (targ);
6306 len = TREE_VEC_LENGTH (packed_args);
6309 for (idx = 0; idx < len; ++idx)
6311 tree targ_parms = NULL_TREE;
6314 /* Extract the next argument from the argument
6316 targ = TREE_VEC_ELT (packed_args, idx);
6318 if (PACK_EXPANSION_P (targ))
6319 /* Look at the pattern of the pack expansion. */
6320 targ = PACK_EXPANSION_PATTERN (targ);
6322 /* Extract the template parameters from the template
6324 if (TREE_CODE (targ) == TEMPLATE_DECL)
6325 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
6326 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
6327 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
6329 /* Verify that we can coerce the template template
6330 parameters from the template argument to the template
6331 parameter. This requires an exact match. */
6333 && !coerce_template_template_parms
6334 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
6349 --processing_template_decl;
6353 /* Since type attributes aren't mangled, we need to strip them from
6354 template type arguments. */
6357 canonicalize_type_argument (tree arg, tsubst_flags_t complain)
6360 if (!arg || arg == error_mark_node || arg == TYPE_CANONICAL (arg))
6362 mv = TYPE_MAIN_VARIANT (arg);
6363 arg = strip_typedefs (arg);
6364 if (TYPE_ALIGN (arg) != TYPE_ALIGN (mv)
6365 || TYPE_ATTRIBUTES (arg) != TYPE_ATTRIBUTES (mv))
6367 if (complain & tf_warning)
6368 warning (0, "ignoring attributes on template argument %qT", arg);
6369 arg = build_aligned_type (arg, TYPE_ALIGN (mv));
6370 arg = cp_build_type_attribute_variant (arg, TYPE_ATTRIBUTES (mv));
6375 /* Convert the indicated template ARG as necessary to match the
6376 indicated template PARM. Returns the converted ARG, or
6377 error_mark_node if the conversion was unsuccessful. Error and
6378 warning messages are issued under control of COMPLAIN. This
6379 conversion is for the Ith parameter in the parameter list. ARGS is
6380 the full set of template arguments deduced so far. */
6383 convert_template_argument (tree parm,
6386 tsubst_flags_t complain,
6392 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
6394 if (TREE_CODE (arg) == TREE_LIST
6395 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
6397 /* The template argument was the name of some
6398 member function. That's usually
6399 invalid, but static members are OK. In any
6400 case, grab the underlying fields/functions
6401 and issue an error later if required. */
6402 orig_arg = TREE_VALUE (arg);
6403 TREE_TYPE (arg) = unknown_type_node;
6408 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
6409 requires_type = (TREE_CODE (parm) == TYPE_DECL
6410 || requires_tmpl_type);
6412 /* When determining whether an argument pack expansion is a template,
6413 look at the pattern. */
6414 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
6415 arg = PACK_EXPANSION_PATTERN (arg);
6417 /* Deal with an injected-class-name used as a template template arg. */
6418 if (requires_tmpl_type && CLASS_TYPE_P (arg))
6420 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
6421 if (TREE_CODE (t) == TEMPLATE_DECL)
6423 if (cxx_dialect >= cxx0x)
6424 /* OK under DR 1004. */;
6425 else if (complain & tf_warning_or_error)
6426 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
6427 " used as template template argument", TYPE_NAME (arg));
6428 else if (flag_pedantic_errors)
6436 ((TREE_CODE (arg) == TEMPLATE_DECL
6437 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
6438 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6439 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
6442 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6443 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
6444 arg = TYPE_STUB_DECL (arg);
6446 is_type = TYPE_P (arg) || is_tmpl_type;
6448 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
6449 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
6451 if (TREE_CODE (TREE_OPERAND (arg, 1)) == BIT_NOT_EXPR)
6453 if (complain & tf_error)
6454 error ("invalid use of destructor %qE as a type", orig_arg);
6455 return error_mark_node;
6458 permerror (input_location,
6459 "to refer to a type member of a template parameter, "
6460 "use %<typename %E%>", orig_arg);
6462 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
6463 TREE_OPERAND (arg, 1),
6465 complain & tf_error);
6469 if (is_type != requires_type)
6473 if (complain & tf_error)
6475 error ("type/value mismatch at argument %d in template "
6476 "parameter list for %qD",
6479 error (" expected a constant of type %qT, got %qT",
6481 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6482 else if (requires_tmpl_type)
6483 error (" expected a class template, got %qE", orig_arg);
6485 error (" expected a type, got %qE", orig_arg);
6488 return error_mark_node;
6490 if (is_tmpl_type ^ requires_tmpl_type)
6492 if (in_decl && (complain & tf_error))
6494 error ("type/value mismatch at argument %d in template "
6495 "parameter list for %qD",
6498 error (" expected a type, got %qT", DECL_NAME (arg));
6500 error (" expected a class template, got %qT", orig_arg);
6502 return error_mark_node;
6507 if (requires_tmpl_type)
6509 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6510 /* The number of argument required is not known yet.
6511 Just accept it for now. */
6512 val = TREE_TYPE (arg);
6515 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6518 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6520 if (coerce_template_template_parms (parmparm, argparm,
6526 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6528 if (val != error_mark_node)
6530 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6531 val = TREE_TYPE (val);
6532 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6533 val = make_pack_expansion (val);
6538 if (in_decl && (complain & tf_error))
6540 error ("type/value mismatch at argument %d in "
6541 "template parameter list for %qD",
6543 error (" expected a template of type %qD, got %qT",
6547 val = error_mark_node;
6553 /* We only form one instance of each template specialization.
6554 Therefore, if we use a non-canonical variant (i.e., a
6555 typedef), any future messages referring to the type will use
6556 the typedef, which is confusing if those future uses do not
6557 themselves also use the typedef. */
6559 val = canonicalize_type_argument (val, complain);
6563 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6565 if (invalid_nontype_parm_type_p (t, complain))
6566 return error_mark_node;
6568 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6570 if (same_type_p (t, TREE_TYPE (orig_arg)))
6574 /* Not sure if this is reachable, but it doesn't hurt
6576 error ("type mismatch in nontype parameter pack");
6577 val = error_mark_node;
6580 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
6581 /* We used to call digest_init here. However, digest_init
6582 will report errors, which we don't want when complain
6583 is zero. More importantly, digest_init will try too
6584 hard to convert things: for example, `0' should not be
6585 converted to pointer type at this point according to
6586 the standard. Accepting this is not merely an
6587 extension, since deciding whether or not these
6588 conversions can occur is part of determining which
6589 function template to call, or whether a given explicit
6590 argument specification is valid. */
6591 val = convert_nontype_argument (t, orig_arg, complain);
6595 if (val == NULL_TREE)
6596 val = error_mark_node;
6597 else if (val == error_mark_node && (complain & tf_error))
6598 error ("could not convert template argument %qE to %qT", orig_arg, t);
6600 if (TREE_CODE (val) == SCOPE_REF)
6602 /* Strip typedefs from the SCOPE_REF. */
6603 tree type = canonicalize_type_argument (TREE_TYPE (val), complain);
6604 tree scope = canonicalize_type_argument (TREE_OPERAND (val, 0),
6606 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6607 QUALIFIED_NAME_IS_TEMPLATE (val));
6614 /* Coerces the remaining template arguments in INNER_ARGS (from
6615 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6616 Returns the coerced argument pack. PARM_IDX is the position of this
6617 parameter in the template parameter list. ARGS is the original
6618 template argument list. */
6620 coerce_template_parameter_pack (tree parms,
6628 tsubst_flags_t complain)
6630 tree parm = TREE_VEC_ELT (parms, parm_idx);
6631 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6634 tree packed_types = NULL_TREE;
6636 if (arg_idx > nargs)
6639 packed_args = make_tree_vec (nargs - arg_idx);
6641 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6642 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6644 /* When the template parameter is a non-type template
6645 parameter pack whose type uses parameter packs, we need
6646 to look at each of the template arguments
6647 separately. Build a vector of the types for these
6648 non-type template parameters in PACKED_TYPES. */
6650 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6651 packed_types = tsubst_pack_expansion (expansion, args,
6654 if (packed_types == error_mark_node)
6655 return error_mark_node;
6657 /* Check that we have the right number of arguments. */
6659 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6660 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6663 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6664 error ("wrong number of template arguments (%d, should be %d)",
6665 nargs, needed_parms);
6666 return error_mark_node;
6669 /* If we aren't able to check the actual arguments now
6670 (because they haven't been expanded yet), we can at least
6671 verify that all of the types used for the non-type
6672 template parameter pack are, in fact, valid for non-type
6673 template parameters. */
6675 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6677 int j, len = TREE_VEC_LENGTH (packed_types);
6678 for (j = 0; j < len; ++j)
6680 tree t = TREE_VEC_ELT (packed_types, j);
6681 if (invalid_nontype_parm_type_p (t, complain))
6682 return error_mark_node;
6687 /* Convert the remaining arguments, which will be a part of the
6688 parameter pack "parm". */
6689 for (; arg_idx < nargs; ++arg_idx)
6691 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6692 tree actual_parm = TREE_VALUE (parm);
6694 if (packed_types && !PACK_EXPANSION_P (arg))
6696 /* When we have a vector of types (corresponding to the
6697 non-type template parameter pack that uses parameter
6698 packs in its type, as mention above), and the
6699 argument is not an expansion (which expands to a
6700 currently unknown number of arguments), clone the
6701 parm and give it the next type in PACKED_TYPES. */
6702 actual_parm = copy_node (actual_parm);
6703 TREE_TYPE (actual_parm) =
6704 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6707 if (arg != error_mark_node)
6708 arg = convert_template_argument (actual_parm,
6709 arg, new_args, complain, parm_idx,
6711 if (arg == error_mark_node)
6713 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6716 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6717 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6718 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6721 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6722 TREE_TYPE (argument_pack)
6723 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6724 TREE_CONSTANT (argument_pack) = 1;
6727 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6728 #ifdef ENABLE_CHECKING
6729 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6730 TREE_VEC_LENGTH (packed_args));
6732 return argument_pack;
6735 /* Convert all template arguments to their appropriate types, and
6736 return a vector containing the innermost resulting template
6737 arguments. If any error occurs, return error_mark_node. Error and
6738 warning messages are issued under control of COMPLAIN.
6740 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6741 for arguments not specified in ARGS. Otherwise, if
6742 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6743 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6744 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6748 coerce_template_parms (tree parms,
6751 tsubst_flags_t complain,
6752 bool require_all_args,
6753 bool use_default_args)
6755 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6758 tree new_inner_args;
6759 int saved_unevaluated_operand;
6760 int saved_inhibit_evaluation_warnings;
6762 /* When used as a boolean value, indicates whether this is a
6763 variadic template parameter list. Since it's an int, we can also
6764 subtract it from nparms to get the number of non-variadic
6767 int post_variadic_parms = 0;
6769 if (args == error_mark_node)
6770 return error_mark_node;
6772 nparms = TREE_VEC_LENGTH (parms);
6774 /* Determine if there are any parameter packs. */
6775 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6777 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6779 ++post_variadic_parms;
6780 if (template_parameter_pack_p (tparm))
6784 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6785 /* If there are no parameters that follow a parameter pack, we need to
6786 expand any argument packs so that we can deduce a parameter pack from
6787 some non-packed args followed by an argument pack, as in variadic85.C.
6788 If there are such parameters, we need to leave argument packs intact
6789 so the arguments are assigned properly. This can happen when dealing
6790 with a nested class inside a partial specialization of a class
6791 template, as in variadic92.C, or when deducing a template parameter pack
6792 from a sub-declarator, as in variadic114.C. */
6793 if (!post_variadic_parms)
6794 inner_args = expand_template_argument_pack (inner_args);
6796 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6797 if ((nargs > nparms && !variadic_p)
6798 || (nargs < nparms - variadic_p
6800 && (!use_default_args
6801 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6802 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6804 if (complain & tf_error)
6808 nparms -= variadic_p;
6809 error ("wrong number of template arguments "
6810 "(%d, should be %d or more)", nargs, nparms);
6813 error ("wrong number of template arguments "
6814 "(%d, should be %d)", nargs, nparms);
6817 error ("provided for %q+D", in_decl);
6820 return error_mark_node;
6823 /* We need to evaluate the template arguments, even though this
6824 template-id may be nested within a "sizeof". */
6825 saved_unevaluated_operand = cp_unevaluated_operand;
6826 cp_unevaluated_operand = 0;
6827 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6828 c_inhibit_evaluation_warnings = 0;
6829 new_inner_args = make_tree_vec (nparms);
6830 new_args = add_outermost_template_args (args, new_inner_args);
6831 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6836 /* Get the Ith template parameter. */
6837 parm = TREE_VEC_ELT (parms, parm_idx);
6839 if (parm == error_mark_node)
6841 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6845 /* Calculate the next argument. */
6846 if (arg_idx < nargs)
6847 arg = TREE_VEC_ELT (inner_args, arg_idx);
6851 if (template_parameter_pack_p (TREE_VALUE (parm))
6852 && !(arg && ARGUMENT_PACK_P (arg)))
6854 /* All remaining arguments will be placed in the
6855 template parameter pack PARM. */
6856 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6857 inner_args, arg_idx,
6861 /* Store this argument. */
6862 if (arg == error_mark_node)
6864 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6866 /* We are done with all of the arguments. */
6873 if (PACK_EXPANSION_P (arg))
6875 /* We don't know how many args we have yet, just
6876 use the unconverted ones for now. */
6877 new_inner_args = args;
6881 else if (require_all_args)
6883 /* There must be a default arg in this case. */
6884 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6886 /* The position of the first default template argument,
6887 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6889 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6890 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6895 if (arg == error_mark_node)
6897 if (complain & tf_error)
6898 error ("template argument %d is invalid", arg_idx + 1);
6901 /* This only occurs if there was an error in the template
6902 parameter list itself (which we would already have
6903 reported) that we are trying to recover from, e.g., a class
6904 template with a parameter list such as
6905 template<typename..., typename>. */
6908 arg = convert_template_argument (TREE_VALUE (parm),
6909 arg, new_args, complain,
6912 if (arg == error_mark_node)
6914 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6916 cp_unevaluated_operand = saved_unevaluated_operand;
6917 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6920 return error_mark_node;
6922 #ifdef ENABLE_CHECKING
6923 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6924 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6925 TREE_VEC_LENGTH (new_inner_args));
6928 return new_inner_args;
6931 /* Returns 1 if template args OT and NT are equivalent. */
6934 template_args_equal (tree ot, tree nt)
6938 if (nt == NULL_TREE || ot == NULL_TREE)
6941 if (TREE_CODE (nt) == TREE_VEC)
6942 /* For member templates */
6943 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6944 else if (PACK_EXPANSION_P (ot))
6945 return (PACK_EXPANSION_P (nt)
6946 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6947 PACK_EXPANSION_PATTERN (nt))
6948 && template_args_equal (PACK_EXPANSION_EXTRA_ARGS (ot),
6949 PACK_EXPANSION_EXTRA_ARGS (nt)));
6950 else if (ARGUMENT_PACK_P (ot))
6955 if (!ARGUMENT_PACK_P (nt))
6958 opack = ARGUMENT_PACK_ARGS (ot);
6959 npack = ARGUMENT_PACK_ARGS (nt);
6960 len = TREE_VEC_LENGTH (opack);
6961 if (TREE_VEC_LENGTH (npack) != len)
6963 for (i = 0; i < len; ++i)
6964 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6965 TREE_VEC_ELT (npack, i)))
6969 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6971 /* We get here probably because we are in the middle of substituting
6972 into the pattern of a pack expansion. In that case the
6973 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6974 interested in. So we want to use the initial pack argument for
6976 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6977 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6978 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6979 return template_args_equal (ot, nt);
6981 else if (TYPE_P (nt))
6982 return TYPE_P (ot) && same_type_p (ot, nt);
6983 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6986 return cp_tree_equal (ot, nt);
6989 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets of
6990 template arguments. Returns 0 otherwise, and updates OLDARG_PTR and
6991 NEWARG_PTR with the offending arguments if they are non-NULL. */
6994 comp_template_args_with_info (tree oldargs, tree newargs,
6995 tree *oldarg_ptr, tree *newarg_ptr)
6999 if (oldargs == newargs)
7002 if (!oldargs || !newargs)
7005 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
7008 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
7010 tree nt = TREE_VEC_ELT (newargs, i);
7011 tree ot = TREE_VEC_ELT (oldargs, i);
7013 if (! template_args_equal (ot, nt))
7015 if (oldarg_ptr != NULL)
7017 if (newarg_ptr != NULL)
7025 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
7026 of template arguments. Returns 0 otherwise. */
7029 comp_template_args (tree oldargs, tree newargs)
7031 return comp_template_args_with_info (oldargs, newargs, NULL, NULL);
7035 add_pending_template (tree d)
7037 tree ti = (TYPE_P (d)
7038 ? CLASSTYPE_TEMPLATE_INFO (d)
7039 : DECL_TEMPLATE_INFO (d));
7040 struct pending_template *pt;
7043 if (TI_PENDING_TEMPLATE_FLAG (ti))
7046 /* We are called both from instantiate_decl, where we've already had a
7047 tinst_level pushed, and instantiate_template, where we haven't.
7049 level = !current_tinst_level || current_tinst_level->decl != d;
7052 push_tinst_level (d);
7054 pt = ggc_alloc_pending_template ();
7056 pt->tinst = current_tinst_level;
7057 if (last_pending_template)
7058 last_pending_template->next = pt;
7060 pending_templates = pt;
7062 last_pending_template = pt;
7064 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
7071 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
7072 ARGLIST. Valid choices for FNS are given in the cp-tree.def
7073 documentation for TEMPLATE_ID_EXPR. */
7076 lookup_template_function (tree fns, tree arglist)
7080 if (fns == error_mark_node || arglist == error_mark_node)
7081 return error_mark_node;
7083 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
7085 if (!is_overloaded_fn (fns) && TREE_CODE (fns) != IDENTIFIER_NODE)
7087 error ("%q#D is not a function template", fns);
7088 return error_mark_node;
7091 if (BASELINK_P (fns))
7093 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
7095 BASELINK_FUNCTIONS (fns),
7100 type = TREE_TYPE (fns);
7101 if (TREE_CODE (fns) == OVERLOAD || !type)
7102 type = unknown_type_node;
7104 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
7107 /* Within the scope of a template class S<T>, the name S gets bound
7108 (in build_self_reference) to a TYPE_DECL for the class, not a
7109 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
7110 or one of its enclosing classes, and that type is a template,
7111 return the associated TEMPLATE_DECL. Otherwise, the original
7114 Also handle the case when DECL is a TREE_LIST of ambiguous
7115 injected-class-names from different bases. */
7118 maybe_get_template_decl_from_type_decl (tree decl)
7120 if (decl == NULL_TREE)
7123 /* DR 176: A lookup that finds an injected-class-name (10.2
7124 [class.member.lookup]) can result in an ambiguity in certain cases
7125 (for example, if it is found in more than one base class). If all of
7126 the injected-class-names that are found refer to specializations of
7127 the same class template, and if the name is followed by a
7128 template-argument-list, the reference refers to the class template
7129 itself and not a specialization thereof, and is not ambiguous. */
7130 if (TREE_CODE (decl) == TREE_LIST)
7132 tree t, tmpl = NULL_TREE;
7133 for (t = decl; t; t = TREE_CHAIN (t))
7135 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
7138 else if (tmpl != elt)
7141 if (tmpl && t == NULL_TREE)
7147 return (decl != NULL_TREE
7148 && DECL_SELF_REFERENCE_P (decl)
7149 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
7150 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
7153 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
7154 parameters, find the desired type.
7156 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
7158 IN_DECL, if non-NULL, is the template declaration we are trying to
7161 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
7162 the class we are looking up.
7164 Issue error and warning messages under control of COMPLAIN.
7166 If the template class is really a local class in a template
7167 function, then the FUNCTION_CONTEXT is the function in which it is
7170 ??? Note that this function is currently called *twice* for each
7171 template-id: the first time from the parser, while creating the
7172 incomplete type (finish_template_type), and the second type during the
7173 real instantiation (instantiate_template_class). This is surely something
7174 that we want to avoid. It also causes some problems with argument
7175 coercion (see convert_nontype_argument for more information on this). */
7178 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
7179 int entering_scope, tsubst_flags_t complain)
7181 tree templ = NULL_TREE, parmlist;
7188 if (TREE_CODE (d1) == IDENTIFIER_NODE)
7190 tree value = innermost_non_namespace_value (d1);
7191 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
7196 push_decl_namespace (context);
7197 templ = lookup_name (d1);
7198 templ = maybe_get_template_decl_from_type_decl (templ);
7200 pop_decl_namespace ();
7203 context = DECL_CONTEXT (templ);
7205 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
7207 tree type = TREE_TYPE (d1);
7209 /* If we are declaring a constructor, say A<T>::A<T>, we will get
7210 an implicit typename for the second A. Deal with it. */
7211 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
7212 type = TREE_TYPE (type);
7214 if (CLASSTYPE_TEMPLATE_INFO (type))
7216 templ = CLASSTYPE_TI_TEMPLATE (type);
7217 d1 = DECL_NAME (templ);
7220 else if (TREE_CODE (d1) == ENUMERAL_TYPE
7221 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
7223 templ = TYPE_TI_TEMPLATE (d1);
7224 d1 = DECL_NAME (templ);
7226 else if (TREE_CODE (d1) == TEMPLATE_DECL
7227 && DECL_TEMPLATE_RESULT (d1)
7228 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
7231 d1 = DECL_NAME (templ);
7232 context = DECL_CONTEXT (templ);
7235 /* Issue an error message if we didn't find a template. */
7238 if (complain & tf_error)
7239 error ("%qT is not a template", d1);
7240 return error_mark_node;
7243 if (TREE_CODE (templ) != TEMPLATE_DECL
7244 /* Make sure it's a user visible template, if it was named by
7246 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
7247 && !PRIMARY_TEMPLATE_P (templ)))
7249 if (complain & tf_error)
7251 error ("non-template type %qT used as a template", d1);
7253 error ("for template declaration %q+D", in_decl);
7255 return error_mark_node;
7258 complain &= ~tf_user;
7260 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
7262 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
7263 template arguments */
7269 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
7271 /* Consider an example where a template template parameter declared as
7273 template <class T, class U = std::allocator<T> > class TT
7275 The template parameter level of T and U are one level larger than
7276 of TT. To proper process the default argument of U, say when an
7277 instantiation `TT<int>' is seen, we need to build the full
7278 arguments containing {int} as the innermost level. Outer levels,
7279 available when not appearing as default template argument, can be
7280 obtained from the arguments of the enclosing template.
7282 Suppose that TT is later substituted with std::vector. The above
7283 instantiation is `TT<int, std::allocator<T> >' with TT at
7284 level 1, and T at level 2, while the template arguments at level 1
7285 becomes {std::vector} and the inner level 2 is {int}. */
7287 outer = DECL_CONTEXT (templ);
7289 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
7290 else if (current_template_parms)
7291 /* This is an argument of the current template, so we haven't set
7292 DECL_CONTEXT yet. */
7293 outer = current_template_args ();
7296 arglist = add_to_template_args (outer, arglist);
7298 arglist2 = coerce_template_parms (parmlist, arglist, templ,
7300 /*require_all_args=*/true,
7301 /*use_default_args=*/true);
7302 if (arglist2 == error_mark_node
7303 || (!uses_template_parms (arglist2)
7304 && check_instantiated_args (templ, arglist2, complain)))
7305 return error_mark_node;
7307 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
7312 tree template_type = TREE_TYPE (templ);
7315 tree found = NULL_TREE;
7318 int is_dependent_type;
7319 int use_partial_inst_tmpl = false;
7321 if (template_type == error_mark_node)
7322 /* An error occured while building the template TEMPL, and a
7323 diagnostic has most certainly been emitted for that
7324 already. Let's propagate that error. */
7325 return error_mark_node;
7327 gen_tmpl = most_general_template (templ);
7328 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
7329 parm_depth = TMPL_PARMS_DEPTH (parmlist);
7330 arg_depth = TMPL_ARGS_DEPTH (arglist);
7332 if (arg_depth == 1 && parm_depth > 1)
7334 /* We've been given an incomplete set of template arguments.
7337 template <class T> struct S1 {
7338 template <class U> struct S2 {};
7339 template <class U> struct S2<U*> {};
7342 we will be called with an ARGLIST of `U*', but the
7343 TEMPLATE will be `template <class T> template
7344 <class U> struct S1<T>::S2'. We must fill in the missing
7347 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
7349 arg_depth = TMPL_ARGS_DEPTH (arglist);
7352 /* Now we should have enough arguments. */
7353 gcc_assert (parm_depth == arg_depth);
7355 /* From here on, we're only interested in the most general
7358 /* Calculate the BOUND_ARGS. These will be the args that are
7359 actually tsubst'd into the definition to create the
7363 /* We have multiple levels of arguments to coerce, at once. */
7365 int saved_depth = TMPL_ARGS_DEPTH (arglist);
7367 tree bound_args = make_tree_vec (parm_depth);
7369 for (i = saved_depth,
7370 t = DECL_TEMPLATE_PARMS (gen_tmpl);
7371 i > 0 && t != NULL_TREE;
7372 --i, t = TREE_CHAIN (t))
7375 if (i == saved_depth)
7376 a = coerce_template_parms (TREE_VALUE (t),
7379 /*require_all_args=*/true,
7380 /*use_default_args=*/true);
7382 /* Outer levels should have already been coerced. */
7383 a = TMPL_ARGS_LEVEL (arglist, i);
7385 /* Don't process further if one of the levels fails. */
7386 if (a == error_mark_node)
7388 /* Restore the ARGLIST to its full size. */
7389 TREE_VEC_LENGTH (arglist) = saved_depth;
7390 return error_mark_node;
7393 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
7395 /* We temporarily reduce the length of the ARGLIST so
7396 that coerce_template_parms will see only the arguments
7397 corresponding to the template parameters it is
7399 TREE_VEC_LENGTH (arglist)--;
7402 /* Restore the ARGLIST to its full size. */
7403 TREE_VEC_LENGTH (arglist) = saved_depth;
7405 arglist = bound_args;
7409 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
7410 INNERMOST_TEMPLATE_ARGS (arglist),
7413 /*require_all_args=*/true,
7414 /*use_default_args=*/true);
7416 if (arglist == error_mark_node)
7417 /* We were unable to bind the arguments. */
7418 return error_mark_node;
7420 /* In the scope of a template class, explicit references to the
7421 template class refer to the type of the template, not any
7422 instantiation of it. For example, in:
7424 template <class T> class C { void f(C<T>); }
7426 the `C<T>' is just the same as `C'. Outside of the
7427 class, however, such a reference is an instantiation. */
7429 || !PRIMARY_TEMPLATE_P (gen_tmpl)
7430 || currently_open_class (template_type))
7431 /* comp_template_args is expensive, check it last. */
7432 && comp_template_args (TYPE_TI_ARGS (template_type),
7434 return template_type;
7436 /* If we already have this specialization, return it. */
7437 elt.tmpl = gen_tmpl;
7439 hash = hash_specialization (&elt);
7440 entry = (spec_entry *) htab_find_with_hash (type_specializations,
7446 is_dependent_type = uses_template_parms (arglist);
7448 /* If the deduced arguments are invalid, then the binding
7450 if (!is_dependent_type
7451 && check_instantiated_args (gen_tmpl,
7452 INNERMOST_TEMPLATE_ARGS (arglist),
7454 return error_mark_node;
7456 if (!is_dependent_type
7457 && !PRIMARY_TEMPLATE_P (gen_tmpl)
7458 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
7459 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
7461 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
7462 DECL_NAME (gen_tmpl),
7463 /*tag_scope=*/ts_global);
7467 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
7470 context = global_namespace;
7472 /* Create the type. */
7473 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
7475 if (!is_dependent_type)
7477 set_current_access_from_decl (TYPE_NAME (template_type));
7478 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
7479 tsubst (ENUM_UNDERLYING_TYPE (template_type),
7480 arglist, complain, in_decl),
7481 SCOPED_ENUM_P (template_type), NULL);
7485 /* We don't want to call start_enum for this type, since
7486 the values for the enumeration constants may involve
7487 template parameters. And, no one should be interested
7488 in the enumeration constants for such a type. */
7489 t = cxx_make_type (ENUMERAL_TYPE);
7490 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
7492 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
7493 ENUM_FIXED_UNDERLYING_TYPE_P (t)
7494 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type);
7496 else if (DECL_ALIAS_TEMPLATE_P (gen_tmpl))
7498 /* The user referred to a specialization of an alias
7499 template represented by GEN_TMPL.
7501 [temp.alias]/2 says:
7503 When a template-id refers to the specialization of an
7504 alias template, it is equivalent to the associated
7505 type obtained by substitution of its
7506 template-arguments for the template-parameters in the
7507 type-id of the alias template. */
7509 t = tsubst (TREE_TYPE (gen_tmpl), arglist, complain, in_decl);
7510 /* Note that the call above (by indirectly calling
7511 register_specialization in tsubst_decl) registers the
7512 TYPE_DECL representing the specialization of the alias
7513 template. So next time someone substitutes ARGLIST for
7514 the template parms into the alias template (GEN_TMPL),
7515 she'll get that TYPE_DECL back. */
7517 if (t == error_mark_node)
7520 else if (CLASS_TYPE_P (template_type))
7522 t = make_class_type (TREE_CODE (template_type));
7523 CLASSTYPE_DECLARED_CLASS (t)
7524 = CLASSTYPE_DECLARED_CLASS (template_type);
7525 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7526 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7528 /* A local class. Make sure the decl gets registered properly. */
7529 if (context == current_function_decl)
7530 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7532 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7533 /* This instantiation is another name for the primary
7534 template type. Set the TYPE_CANONICAL field
7536 TYPE_CANONICAL (t) = template_type;
7537 else if (any_template_arguments_need_structural_equality_p (arglist))
7538 /* Some of the template arguments require structural
7539 equality testing, so this template class requires
7540 structural equality testing. */
7541 SET_TYPE_STRUCTURAL_EQUALITY (t);
7546 /* If we called start_enum or pushtag above, this information
7547 will already be set up. */
7550 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7552 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7553 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7554 DECL_SOURCE_LOCATION (type_decl)
7555 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7558 type_decl = TYPE_NAME (t);
7560 if (CLASS_TYPE_P (template_type))
7562 TREE_PRIVATE (type_decl)
7563 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
7564 TREE_PROTECTED (type_decl)
7565 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
7566 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7568 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7569 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7573 /* Let's consider the explicit specialization of a member
7574 of a class template specialization that is implicitely instantiated,
7579 template<class U> struct M {}; //#0
7584 struct S<int>::M<char> //#1
7588 [temp.expl.spec]/4 says this is valid.
7590 In this case, when we write:
7593 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7596 When we encounter #1, we want to store the partial instantiation
7597 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7599 For all cases other than this "explicit specialization of member of a
7600 class template", we just want to store the most general template into
7601 the CLASSTYPE_TI_TEMPLATE of M.
7603 This case of "explicit specialization of member of a class template"
7605 1/ the enclosing class is an instantiation of, and therefore not
7606 the same as, the context of the most general template, and
7607 2/ we aren't looking at the partial instantiation itself, i.e.
7608 the innermost arguments are not the same as the innermost parms of
7609 the most general template.
7611 So it's only when 1/ and 2/ happens that we want to use the partial
7612 instantiation of the member template in lieu of its most general
7615 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7616 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7617 /* the enclosing class must be an instantiation... */
7618 && CLASS_TYPE_P (context)
7619 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7621 tree partial_inst_args;
7622 TREE_VEC_LENGTH (arglist)--;
7623 ++processing_template_decl;
7625 tsubst (INNERMOST_TEMPLATE_ARGS
7626 (TYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7627 arglist, complain, NULL_TREE);
7628 --processing_template_decl;
7629 TREE_VEC_LENGTH (arglist)++;
7630 use_partial_inst_tmpl =
7631 /*...and we must not be looking at the partial instantiation
7633 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7637 if (!use_partial_inst_tmpl)
7638 /* This case is easy; there are no member templates involved. */
7642 /* This is a full instantiation of a member template. Find
7643 the partial instantiation of which this is an instance. */
7645 /* Temporarily reduce by one the number of levels in the ARGLIST
7646 so as to avoid comparing the last set of arguments. */
7647 TREE_VEC_LENGTH (arglist)--;
7648 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7649 TREE_VEC_LENGTH (arglist)++;
7650 /* FOUND is either a proper class type, or an alias
7651 template specialization. In the later case, it's a
7652 TYPE_DECL, resulting from the substituting of arguments
7653 for parameters in the TYPE_DECL of the alias template
7654 done earlier. So be careful while getting the template
7656 found = TREE_CODE (found) == TYPE_DECL
7657 ? TYPE_TI_TEMPLATE (TREE_TYPE (found))
7658 : CLASSTYPE_TI_TEMPLATE (found);
7661 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7664 slot = htab_find_slot_with_hash (type_specializations,
7665 &elt, hash, INSERT);
7666 entry = ggc_alloc_spec_entry ();
7670 /* Note this use of the partial instantiation so we can check it
7671 later in maybe_process_partial_specialization. */
7672 DECL_TEMPLATE_INSTANTIATIONS (templ)
7673 = tree_cons (arglist, t,
7674 DECL_TEMPLATE_INSTANTIATIONS (templ));
7676 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
7677 /* Now that the type has been registered on the instantiations
7678 list, we set up the enumerators. Because the enumeration
7679 constants may involve the enumeration type itself, we make
7680 sure to register the type first, and then create the
7681 constants. That way, doing tsubst_expr for the enumeration
7682 constants won't result in recursive calls here; we'll find
7683 the instantiation and exit above. */
7684 tsubst_enum (template_type, t, arglist);
7686 if (CLASS_TYPE_P (template_type) && is_dependent_type)
7687 /* If the type makes use of template parameters, the
7688 code that generates debugging information will crash. */
7689 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7691 /* Possibly limit visibility based on template args. */
7692 TREE_PUBLIC (type_decl) = 1;
7693 determine_visibility (type_decl);
7699 /* Wrapper for lookup_template_class_1. */
7702 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
7703 int entering_scope, tsubst_flags_t complain)
7706 timevar_push (TV_TEMPLATE_INST);
7707 ret = lookup_template_class_1 (d1, arglist, in_decl, context,
7708 entering_scope, complain);
7709 timevar_pop (TV_TEMPLATE_INST);
7717 /* True when we should also visit template parameters that occur in
7718 non-deduced contexts. */
7719 bool include_nondeduced_p;
7720 struct pointer_set_t *visited;
7723 /* Called from for_each_template_parm via walk_tree. */
7726 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7729 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7730 tree_fn_t fn = pfd->fn;
7731 void *data = pfd->data;
7734 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7735 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7736 pfd->include_nondeduced_p))
7737 return error_mark_node;
7739 switch (TREE_CODE (t))
7742 if (TYPE_PTRMEMFUNC_P (t))
7748 if (!TYPE_TEMPLATE_INFO (t))
7750 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7751 fn, data, pfd->visited,
7752 pfd->include_nondeduced_p))
7753 return error_mark_node;
7757 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7758 fn, data, pfd->visited,
7759 pfd->include_nondeduced_p)
7760 || for_each_template_parm (TYPE_MAX_VALUE (t),
7761 fn, data, pfd->visited,
7762 pfd->include_nondeduced_p))
7763 return error_mark_node;
7767 /* Since we're not going to walk subtrees, we have to do this
7769 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7770 pfd->visited, pfd->include_nondeduced_p))
7771 return error_mark_node;
7775 /* Check the return type. */
7776 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7777 pfd->include_nondeduced_p))
7778 return error_mark_node;
7780 /* Check the parameter types. Since default arguments are not
7781 instantiated until they are needed, the TYPE_ARG_TYPES may
7782 contain expressions that involve template parameters. But,
7783 no-one should be looking at them yet. And, once they're
7784 instantiated, they don't contain template parameters, so
7785 there's no point in looking at them then, either. */
7789 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7790 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7791 pfd->visited, pfd->include_nondeduced_p))
7792 return error_mark_node;
7794 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7795 want walk_tree walking into them itself. */
7801 case UNDERLYING_TYPE:
7802 if (pfd->include_nondeduced_p
7803 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7805 pfd->include_nondeduced_p))
7806 return error_mark_node;
7811 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7812 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7813 pfd->visited, pfd->include_nondeduced_p))
7814 return error_mark_node;
7819 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7820 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7821 pfd->visited, pfd->include_nondeduced_p))
7822 return error_mark_node;
7823 if (DECL_CONTEXT (t)
7824 && pfd->include_nondeduced_p
7825 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7826 pfd->visited, pfd->include_nondeduced_p))
7827 return error_mark_node;
7830 case BOUND_TEMPLATE_TEMPLATE_PARM:
7831 /* Record template parameters such as `T' inside `TT<T>'. */
7832 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7833 pfd->include_nondeduced_p))
7834 return error_mark_node;
7837 case TEMPLATE_TEMPLATE_PARM:
7838 case TEMPLATE_TYPE_PARM:
7839 case TEMPLATE_PARM_INDEX:
7840 if (fn && (*fn)(t, data))
7841 return error_mark_node;
7843 return error_mark_node;
7847 /* A template template parameter is encountered. */
7848 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7849 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7850 pfd->include_nondeduced_p))
7851 return error_mark_node;
7853 /* Already substituted template template parameter */
7859 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7861 pfd->include_nondeduced_p))
7862 return error_mark_node;
7866 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7867 && pfd->include_nondeduced_p
7868 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7869 (TREE_TYPE (t)), fn, data,
7870 pfd->visited, pfd->include_nondeduced_p))
7871 return error_mark_node;
7876 /* If there's no type, then this thing must be some expression
7877 involving template parameters. */
7878 if (!fn && !TREE_TYPE (t))
7879 return error_mark_node;
7884 case IMPLICIT_CONV_EXPR:
7885 case REINTERPRET_CAST_EXPR:
7886 case CONST_CAST_EXPR:
7887 case STATIC_CAST_EXPR:
7888 case DYNAMIC_CAST_EXPR:
7892 case PSEUDO_DTOR_EXPR:
7894 return error_mark_node;
7901 /* We didn't find any template parameters we liked. */
7905 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7906 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7907 call FN with the parameter and the DATA.
7908 If FN returns nonzero, the iteration is terminated, and
7909 for_each_template_parm returns 1. Otherwise, the iteration
7910 continues. If FN never returns a nonzero value, the value
7911 returned by for_each_template_parm is 0. If FN is NULL, it is
7912 considered to be the function which always returns 1.
7914 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7915 parameters that occur in non-deduced contexts. When false, only
7916 visits those template parameters that can be deduced. */
7919 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7920 struct pointer_set_t *visited,
7921 bool include_nondeduced_p)
7923 struct pair_fn_data pfd;
7929 pfd.include_nondeduced_p = include_nondeduced_p;
7931 /* Walk the tree. (Conceptually, we would like to walk without
7932 duplicates, but for_each_template_parm_r recursively calls
7933 for_each_template_parm, so we would need to reorganize a fair
7934 bit to use walk_tree_without_duplicates, so we keep our own
7937 pfd.visited = visited;
7939 pfd.visited = pointer_set_create ();
7940 result = cp_walk_tree (&t,
7941 for_each_template_parm_r,
7943 pfd.visited) != NULL_TREE;
7948 pointer_set_destroy (pfd.visited);
7955 /* Returns true if T depends on any template parameter. */
7958 uses_template_parms (tree t)
7961 int saved_processing_template_decl;
7963 saved_processing_template_decl = processing_template_decl;
7964 if (!saved_processing_template_decl)
7965 processing_template_decl = 1;
7967 dependent_p = dependent_type_p (t);
7968 else if (TREE_CODE (t) == TREE_VEC)
7969 dependent_p = any_dependent_template_arguments_p (t);
7970 else if (TREE_CODE (t) == TREE_LIST)
7971 dependent_p = (uses_template_parms (TREE_VALUE (t))
7972 || uses_template_parms (TREE_CHAIN (t)));
7973 else if (TREE_CODE (t) == TYPE_DECL)
7974 dependent_p = dependent_type_p (TREE_TYPE (t));
7977 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
7978 || TREE_CODE (t) == OVERLOAD
7980 || TREE_CODE (t) == IDENTIFIER_NODE
7981 || TREE_CODE (t) == TRAIT_EXPR
7982 || TREE_CODE (t) == CONSTRUCTOR
7983 || CONSTANT_CLASS_P (t))
7984 dependent_p = (type_dependent_expression_p (t)
7985 || value_dependent_expression_p (t));
7988 gcc_assert (t == error_mark_node);
7989 dependent_p = false;
7992 processing_template_decl = saved_processing_template_decl;
7997 /* Returns true if T depends on any template parameter with level LEVEL. */
8000 uses_template_parms_level (tree t, int level)
8002 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
8003 /*include_nondeduced_p=*/true);
8006 /* Returns TRUE iff INST is an instantiation we don't need to do in an
8007 ill-formed translation unit, i.e. a variable or function that isn't
8008 usable in a constant expression. */
8011 neglectable_inst_p (tree d)
8014 && !(TREE_CODE (d) == FUNCTION_DECL ? DECL_DECLARED_CONSTEXPR_P (d)
8015 : decl_maybe_constant_var_p (d)));
8018 /* Returns TRUE iff we should refuse to instantiate DECL because it's
8019 neglectable and instantiated from within an erroneous instantiation. */
8022 limit_bad_template_recursion (tree decl)
8024 struct tinst_level *lev = current_tinst_level;
8025 int errs = errorcount + sorrycount;
8026 if (lev == NULL || errs == 0 || !neglectable_inst_p (decl))
8029 for (; lev; lev = lev->next)
8030 if (neglectable_inst_p (lev->decl))
8033 return (lev && errs > lev->errors);
8036 static int tinst_depth;
8037 extern int max_tinst_depth;
8038 #ifdef GATHER_STATISTICS
8041 static GTY(()) struct tinst_level *last_error_tinst_level;
8043 /* We're starting to instantiate D; record the template instantiation context
8044 for diagnostics and to restore it later. */
8047 push_tinst_level (tree d)
8049 struct tinst_level *new_level;
8051 if (tinst_depth >= max_tinst_depth)
8053 last_error_tinst_level = current_tinst_level;
8054 if (TREE_CODE (d) == TREE_LIST)
8055 error ("template instantiation depth exceeds maximum of %d (use "
8056 "-ftemplate-depth= to increase the maximum) substituting %qS",
8057 max_tinst_depth, d);
8059 error ("template instantiation depth exceeds maximum of %d (use "
8060 "-ftemplate-depth= to increase the maximum) instantiating %qD",
8061 max_tinst_depth, d);
8063 print_instantiation_context ();
8068 /* If the current instantiation caused problems, don't let it instantiate
8069 anything else. Do allow deduction substitution and decls usable in
8070 constant expressions. */
8071 if (limit_bad_template_recursion (d))
8074 new_level = ggc_alloc_tinst_level ();
8075 new_level->decl = d;
8076 new_level->locus = input_location;
8077 new_level->errors = errorcount+sorrycount;
8078 new_level->in_system_header_p = in_system_header;
8079 new_level->next = current_tinst_level;
8080 current_tinst_level = new_level;
8083 #ifdef GATHER_STATISTICS
8084 if (tinst_depth > depth_reached)
8085 depth_reached = tinst_depth;
8091 /* We're done instantiating this template; return to the instantiation
8095 pop_tinst_level (void)
8097 /* Restore the filename and line number stashed away when we started
8098 this instantiation. */
8099 input_location = current_tinst_level->locus;
8100 current_tinst_level = current_tinst_level->next;
8104 /* We're instantiating a deferred template; restore the template
8105 instantiation context in which the instantiation was requested, which
8106 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
8109 reopen_tinst_level (struct tinst_level *level)
8111 struct tinst_level *t;
8114 for (t = level; t; t = t->next)
8117 current_tinst_level = level;
8119 if (current_tinst_level)
8120 current_tinst_level->errors = errorcount+sorrycount;
8124 /* Returns the TINST_LEVEL which gives the original instantiation
8127 struct tinst_level *
8128 outermost_tinst_level (void)
8130 struct tinst_level *level = current_tinst_level;
8133 level = level->next;
8137 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
8140 parameter_of_template_p (tree parm, tree templ)
8145 if (!parm || !templ)
8148 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
8149 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8151 parms = DECL_TEMPLATE_PARMS (templ);
8152 parms = INNERMOST_TEMPLATE_PARMS (parms);
8154 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
8156 tree p = TREE_VALUE (TREE_VEC_ELT (parms, i));
8158 || (DECL_INITIAL (parm)
8159 && DECL_INITIAL (parm) == DECL_INITIAL (p)))
8166 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
8167 vector of template arguments, as for tsubst.
8169 Returns an appropriate tsubst'd friend declaration. */
8172 tsubst_friend_function (tree decl, tree args)
8176 if (TREE_CODE (decl) == FUNCTION_DECL
8177 && DECL_TEMPLATE_INSTANTIATION (decl)
8178 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
8179 /* This was a friend declared with an explicit template
8180 argument list, e.g.:
8184 to indicate that f was a template instantiation, not a new
8185 function declaration. Now, we have to figure out what
8186 instantiation of what template. */
8188 tree template_id, arglist, fns;
8191 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
8193 /* Friend functions are looked up in the containing namespace scope.
8194 We must enter that scope, to avoid finding member functions of the
8195 current class with same name. */
8196 push_nested_namespace (ns);
8197 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
8198 tf_warning_or_error, NULL_TREE,
8199 /*integral_constant_expression_p=*/false);
8200 pop_nested_namespace (ns);
8201 arglist = tsubst (DECL_TI_ARGS (decl), args,
8202 tf_warning_or_error, NULL_TREE);
8203 template_id = lookup_template_function (fns, arglist);
8205 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8206 tmpl = determine_specialization (template_id, new_friend,
8208 /*need_member_template=*/0,
8209 TREE_VEC_LENGTH (args),
8211 return instantiate_template (tmpl, new_args, tf_error);
8214 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8216 /* The NEW_FRIEND will look like an instantiation, to the
8217 compiler, but is not an instantiation from the point of view of
8218 the language. For example, we might have had:
8220 template <class T> struct S {
8221 template <class U> friend void f(T, U);
8224 Then, in S<int>, template <class U> void f(int, U) is not an
8225 instantiation of anything. */
8226 if (new_friend == error_mark_node)
8227 return error_mark_node;
8229 DECL_USE_TEMPLATE (new_friend) = 0;
8230 if (TREE_CODE (decl) == TEMPLATE_DECL)
8232 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
8233 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
8234 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
8237 /* The mangled name for the NEW_FRIEND is incorrect. The function
8238 is not a template instantiation and should not be mangled like
8239 one. Therefore, we forget the mangling here; we'll recompute it
8240 later if we need it. */
8241 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
8243 SET_DECL_RTL (new_friend, NULL);
8244 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
8247 if (DECL_NAMESPACE_SCOPE_P (new_friend))
8250 tree new_friend_template_info;
8251 tree new_friend_result_template_info;
8253 int new_friend_is_defn;
8255 /* We must save some information from NEW_FRIEND before calling
8256 duplicate decls since that function will free NEW_FRIEND if
8258 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
8259 new_friend_is_defn =
8260 (DECL_INITIAL (DECL_TEMPLATE_RESULT
8261 (template_for_substitution (new_friend)))
8263 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
8265 /* This declaration is a `primary' template. */
8266 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
8268 new_friend_result_template_info
8269 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
8272 new_friend_result_template_info = NULL_TREE;
8274 /* Make the init_value nonzero so pushdecl knows this is a defn. */
8275 if (new_friend_is_defn)
8276 DECL_INITIAL (new_friend) = error_mark_node;
8278 /* Inside pushdecl_namespace_level, we will push into the
8279 current namespace. However, the friend function should go
8280 into the namespace of the template. */
8281 ns = decl_namespace_context (new_friend);
8282 push_nested_namespace (ns);
8283 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
8284 pop_nested_namespace (ns);
8286 if (old_decl == error_mark_node)
8287 return error_mark_node;
8289 if (old_decl != new_friend)
8291 /* This new friend declaration matched an existing
8292 declaration. For example, given:
8294 template <class T> void f(T);
8295 template <class U> class C {
8296 template <class T> friend void f(T) {}
8299 the friend declaration actually provides the definition
8300 of `f', once C has been instantiated for some type. So,
8301 old_decl will be the out-of-class template declaration,
8302 while new_friend is the in-class definition.
8304 But, if `f' was called before this point, the
8305 instantiation of `f' will have DECL_TI_ARGS corresponding
8306 to `T' but not to `U', references to which might appear
8307 in the definition of `f'. Previously, the most general
8308 template for an instantiation of `f' was the out-of-class
8309 version; now it is the in-class version. Therefore, we
8310 run through all specialization of `f', adding to their
8311 DECL_TI_ARGS appropriately. In particular, they need a
8312 new set of outer arguments, corresponding to the
8313 arguments for this class instantiation.
8315 The same situation can arise with something like this:
8318 template <class T> class C {
8322 when `C<int>' is instantiated. Now, `f(int)' is defined
8325 if (!new_friend_is_defn)
8326 /* On the other hand, if the in-class declaration does
8327 *not* provide a definition, then we don't want to alter
8328 existing definitions. We can just leave everything
8333 tree new_template = TI_TEMPLATE (new_friend_template_info);
8334 tree new_args = TI_ARGS (new_friend_template_info);
8336 /* Overwrite whatever template info was there before, if
8337 any, with the new template information pertaining to
8339 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
8341 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
8343 /* We should have called reregister_specialization in
8345 gcc_assert (retrieve_specialization (new_template,
8349 /* Instantiate it if the global has already been used. */
8350 if (DECL_ODR_USED (old_decl))
8351 instantiate_decl (old_decl, /*defer_ok=*/true,
8352 /*expl_inst_class_mem_p=*/false);
8358 /* Indicate that the old function template is a partial
8360 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
8361 = new_friend_result_template_info;
8363 gcc_assert (new_template
8364 == most_general_template (new_template));
8365 gcc_assert (new_template != old_decl);
8367 /* Reassign any specializations already in the hash table
8368 to the new more general template, and add the
8369 additional template args. */
8370 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
8374 tree spec = TREE_VALUE (t);
8377 elt.tmpl = old_decl;
8378 elt.args = DECL_TI_ARGS (spec);
8379 elt.spec = NULL_TREE;
8381 htab_remove_elt (decl_specializations, &elt);
8384 = add_outermost_template_args (new_args,
8385 DECL_TI_ARGS (spec));
8387 register_specialization
8388 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
8391 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
8395 /* The information from NEW_FRIEND has been merged into OLD_DECL
8396 by duplicate_decls. */
8397 new_friend = old_decl;
8402 tree context = DECL_CONTEXT (new_friend);
8406 template <class T> class C {
8407 template <class U> friend void C1<U>::f (); // case 1
8408 friend void C2<T>::f (); // case 2
8410 we only need to make sure CONTEXT is a complete type for
8411 case 2. To distinguish between the two cases, we note that
8412 CONTEXT of case 1 remains dependent type after tsubst while
8413 this isn't true for case 2. */
8414 ++processing_template_decl;
8415 dependent_p = dependent_type_p (context);
8416 --processing_template_decl;
8419 && !complete_type_or_else (context, NULL_TREE))
8420 return error_mark_node;
8422 if (COMPLETE_TYPE_P (context))
8424 /* Check to see that the declaration is really present, and,
8425 possibly obtain an improved declaration. */
8426 tree fn = check_classfn (context,
8427 new_friend, NULL_TREE);
8437 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
8438 template arguments, as for tsubst.
8440 Returns an appropriate tsubst'd friend type or error_mark_node on
8444 tsubst_friend_class (tree friend_tmpl, tree args)
8450 context = CP_DECL_CONTEXT (friend_tmpl);
8452 if (context != global_namespace)
8454 if (TREE_CODE (context) == NAMESPACE_DECL)
8455 push_nested_namespace (context);
8457 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
8460 /* Look for a class template declaration. We look for hidden names
8461 because two friend declarations of the same template are the
8462 same. For example, in:
8465 template <typename> friend class F;
8467 template <typename> struct B {
8468 template <typename> friend class F;
8471 both F templates are the same. */
8472 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
8473 /*block_p=*/true, 0,
8474 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
8476 /* But, if we don't find one, it might be because we're in a
8477 situation like this:
8485 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
8486 for `S<int>', not the TEMPLATE_DECL. */
8487 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
8489 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
8490 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
8493 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
8495 /* The friend template has already been declared. Just
8496 check to see that the declarations match, and install any new
8497 default parameters. We must tsubst the default parameters,
8498 of course. We only need the innermost template parameters
8499 because that is all that redeclare_class_template will look
8501 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
8502 > TMPL_ARGS_DEPTH (args))
8505 location_t saved_input_location;
8506 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
8507 args, tf_warning_or_error);
8509 saved_input_location = input_location;
8510 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
8511 redeclare_class_template (TREE_TYPE (tmpl), parms);
8512 input_location = saved_input_location;
8516 friend_type = TREE_TYPE (tmpl);
8520 /* The friend template has not already been declared. In this
8521 case, the instantiation of the template class will cause the
8522 injection of this template into the global scope. */
8523 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
8524 if (tmpl == error_mark_node)
8525 return error_mark_node;
8527 /* The new TMPL is not an instantiation of anything, so we
8528 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
8529 the new type because that is supposed to be the corresponding
8530 template decl, i.e., TMPL. */
8531 DECL_USE_TEMPLATE (tmpl) = 0;
8532 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
8533 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
8534 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
8535 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
8537 /* Inject this template into the global scope. */
8538 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
8541 if (context != global_namespace)
8543 if (TREE_CODE (context) == NAMESPACE_DECL)
8544 pop_nested_namespace (context);
8546 pop_nested_class ();
8552 /* Returns zero if TYPE cannot be completed later due to circularity.
8553 Otherwise returns one. */
8556 can_complete_type_without_circularity (tree type)
8558 if (type == NULL_TREE || type == error_mark_node)
8560 else if (COMPLETE_TYPE_P (type))
8562 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
8563 return can_complete_type_without_circularity (TREE_TYPE (type));
8564 else if (CLASS_TYPE_P (type)
8565 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
8571 /* Apply any attributes which had to be deferred until instantiation
8572 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
8573 ARGS, COMPLAIN, IN_DECL are as tsubst. */
8576 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8577 tree args, tsubst_flags_t complain, tree in_decl)
8579 tree last_dep = NULL_TREE;
8583 for (t = attributes; t; t = TREE_CHAIN (t))
8584 if (ATTR_IS_DEPENDENT (t))
8587 attributes = copy_list (attributes);
8591 if (DECL_P (*decl_p))
8593 if (TREE_TYPE (*decl_p) == error_mark_node)
8595 p = &DECL_ATTRIBUTES (*decl_p);
8598 p = &TYPE_ATTRIBUTES (*decl_p);
8602 tree late_attrs = NULL_TREE;
8603 tree *q = &late_attrs;
8605 for (*p = attributes; *p; )
8608 if (ATTR_IS_DEPENDENT (t))
8610 *p = TREE_CHAIN (t);
8611 TREE_CHAIN (t) = NULL_TREE;
8612 /* If the first attribute argument is an identifier, don't
8613 pass it through tsubst. Attributes like mode, format,
8614 cleanup and several target specific attributes expect it
8617 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8618 && TREE_VALUE (TREE_VALUE (t))
8619 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8620 == IDENTIFIER_NODE))
8623 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8625 /*integral_constant_expression_p=*/false);
8626 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8628 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8633 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8634 /*integral_constant_expression_p=*/false);
8636 q = &TREE_CHAIN (t);
8639 p = &TREE_CHAIN (t);
8642 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8646 /* Perform (or defer) access check for typedefs that were referenced
8647 from within the template TMPL code.
8648 This is a subroutine of instantiate_template and instantiate_class_template.
8649 TMPL is the template to consider and TARGS is the list of arguments of
8653 perform_typedefs_access_check (tree tmpl, tree targs)
8655 location_t saved_location;
8657 qualified_typedef_usage_t *iter;
8660 || (!CLASS_TYPE_P (tmpl)
8661 && TREE_CODE (tmpl) != FUNCTION_DECL))
8664 saved_location = input_location;
8665 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8666 get_types_needing_access_check (tmpl),
8669 tree type_decl = iter->typedef_decl;
8670 tree type_scope = iter->context;
8672 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8675 if (uses_template_parms (type_decl))
8676 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8677 if (uses_template_parms (type_scope))
8678 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8680 /* Make access check error messages point to the location
8681 of the use of the typedef. */
8682 input_location = iter->locus;
8683 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8684 type_decl, type_decl);
8686 input_location = saved_location;
8690 instantiate_class_template_1 (tree type)
8692 tree templ, args, pattern, t, member;
8696 unsigned int saved_maximum_field_alignment;
8698 if (type == error_mark_node)
8699 return error_mark_node;
8701 if (COMPLETE_OR_OPEN_TYPE_P (type)
8702 || uses_template_parms (type))
8705 /* Figure out which template is being instantiated. */
8706 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8707 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8709 /* Determine what specialization of the original template to
8711 t = most_specialized_class (type, templ, tf_warning_or_error);
8712 if (t == error_mark_node)
8714 TYPE_BEING_DEFINED (type) = 1;
8715 return error_mark_node;
8719 /* This TYPE is actually an instantiation of a partial
8720 specialization. We replace the innermost set of ARGS with
8721 the arguments appropriate for substitution. For example,
8724 template <class T> struct S {};
8725 template <class T> struct S<T*> {};
8727 and supposing that we are instantiating S<int*>, ARGS will
8728 presently be {int*} -- but we need {int}. */
8729 pattern = TREE_TYPE (t);
8730 args = TREE_PURPOSE (t);
8734 pattern = TREE_TYPE (templ);
8735 args = CLASSTYPE_TI_ARGS (type);
8738 /* If the template we're instantiating is incomplete, then clearly
8739 there's nothing we can do. */
8740 if (!COMPLETE_TYPE_P (pattern))
8743 /* If we've recursively instantiated too many templates, stop. */
8744 if (! push_tinst_level (type))
8747 /* Now we're really doing the instantiation. Mark the type as in
8748 the process of being defined. */
8749 TYPE_BEING_DEFINED (type) = 1;
8751 /* We may be in the middle of deferred access check. Disable
8753 push_deferring_access_checks (dk_no_deferred);
8755 push_to_top_level ();
8756 /* Use #pragma pack from the template context. */
8757 saved_maximum_field_alignment = maximum_field_alignment;
8758 maximum_field_alignment = TYPE_PRECISION (pattern);
8760 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8762 /* Set the input location to the most specialized template definition.
8763 This is needed if tsubsting causes an error. */
8764 typedecl = TYPE_MAIN_DECL (pattern);
8765 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8766 DECL_SOURCE_LOCATION (typedecl);
8768 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8769 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8770 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8771 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8772 if (ANON_AGGR_TYPE_P (pattern))
8773 SET_ANON_AGGR_TYPE_P (type);
8774 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8776 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8777 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8778 /* Adjust visibility for template arguments. */
8779 determine_visibility (TYPE_MAIN_DECL (type));
8781 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8783 pbinfo = TYPE_BINFO (pattern);
8785 /* We should never instantiate a nested class before its enclosing
8786 class; we need to look up the nested class by name before we can
8787 instantiate it, and that lookup should instantiate the enclosing
8789 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8790 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8792 base_list = NULL_TREE;
8793 if (BINFO_N_BASE_BINFOS (pbinfo))
8799 /* We must enter the scope containing the type, as that is where
8800 the accessibility of types named in dependent bases are
8802 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8804 /* Substitute into each of the bases to determine the actual
8806 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8809 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8810 tree expanded_bases = NULL_TREE;
8813 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8816 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8817 args, tf_error, NULL_TREE);
8818 if (expanded_bases == error_mark_node)
8821 len = TREE_VEC_LENGTH (expanded_bases);
8824 for (idx = 0; idx < len; idx++)
8827 /* Extract the already-expanded base class. */
8828 base = TREE_VEC_ELT (expanded_bases, idx);
8830 /* Substitute to figure out the base class. */
8831 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8834 if (base == error_mark_node)
8837 base_list = tree_cons (access, base, base_list);
8838 if (BINFO_VIRTUAL_P (pbase_binfo))
8839 TREE_TYPE (base_list) = integer_type_node;
8843 /* The list is now in reverse order; correct that. */
8844 base_list = nreverse (base_list);
8847 pop_scope (pushed_scope);
8849 /* Now call xref_basetypes to set up all the base-class
8851 xref_basetypes (type, base_list);
8853 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8854 (int) ATTR_FLAG_TYPE_IN_PLACE,
8855 args, tf_error, NULL_TREE);
8856 fixup_attribute_variants (type);
8858 /* Now that our base classes are set up, enter the scope of the
8859 class, so that name lookups into base classes, etc. will work
8860 correctly. This is precisely analogous to what we do in
8861 begin_class_definition when defining an ordinary non-template
8862 class, except we also need to push the enclosing classes. */
8863 push_nested_class (type);
8865 /* Now members are processed in the order of declaration. */
8866 for (member = CLASSTYPE_DECL_LIST (pattern);
8867 member; member = TREE_CHAIN (member))
8869 tree t = TREE_VALUE (member);
8871 if (TREE_PURPOSE (member))
8875 /* Build new CLASSTYPE_NESTED_UTDS. */
8878 bool class_template_p;
8880 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8881 && TYPE_LANG_SPECIFIC (t)
8882 && CLASSTYPE_IS_TEMPLATE (t));
8883 /* If the member is a class template, then -- even after
8884 substitution -- there may be dependent types in the
8885 template argument list for the class. We increment
8886 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8887 that function will assume that no types are dependent
8888 when outside of a template. */
8889 if (class_template_p)
8890 ++processing_template_decl;
8891 newtag = tsubst (t, args, tf_error, NULL_TREE);
8892 if (class_template_p)
8893 --processing_template_decl;
8894 if (newtag == error_mark_node)
8897 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8899 tree name = TYPE_IDENTIFIER (t);
8901 if (class_template_p)
8902 /* Unfortunately, lookup_template_class sets
8903 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8904 instantiation (i.e., for the type of a member
8905 template class nested within a template class.)
8906 This behavior is required for
8907 maybe_process_partial_specialization to work
8908 correctly, but is not accurate in this case;
8909 the TAG is not an instantiation of anything.
8910 (The corresponding TEMPLATE_DECL is an
8911 instantiation, but the TYPE is not.) */
8912 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8914 /* Now, we call pushtag to put this NEWTAG into the scope of
8915 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8916 pushtag calling push_template_decl. We don't have to do
8917 this for enums because it will already have been done in
8920 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8921 pushtag (name, newtag, /*tag_scope=*/ts_current);
8924 else if (TREE_CODE (t) == FUNCTION_DECL
8925 || DECL_FUNCTION_TEMPLATE_P (t))
8927 /* Build new TYPE_METHODS. */
8930 if (TREE_CODE (t) == TEMPLATE_DECL)
8931 ++processing_template_decl;
8932 r = tsubst (t, args, tf_error, NULL_TREE);
8933 if (TREE_CODE (t) == TEMPLATE_DECL)
8934 --processing_template_decl;
8935 set_current_access_from_decl (r);
8936 finish_member_declaration (r);
8937 /* Instantiate members marked with attribute used. */
8938 if (r != error_mark_node && DECL_PRESERVE_P (r))
8943 /* Build new TYPE_FIELDS. */
8944 if (TREE_CODE (t) == STATIC_ASSERT)
8947 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8948 tf_warning_or_error, NULL_TREE,
8949 /*integral_constant_expression_p=*/true);
8950 finish_static_assert (condition,
8951 STATIC_ASSERT_MESSAGE (t),
8952 STATIC_ASSERT_SOURCE_LOCATION (t),
8955 else if (TREE_CODE (t) != CONST_DECL)
8959 /* The file and line for this declaration, to
8960 assist in error message reporting. Since we
8961 called push_tinst_level above, we don't need to
8963 input_location = DECL_SOURCE_LOCATION (t);
8965 if (TREE_CODE (t) == TEMPLATE_DECL)
8966 ++processing_template_decl;
8967 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8968 if (TREE_CODE (t) == TEMPLATE_DECL)
8969 --processing_template_decl;
8970 if (TREE_CODE (r) == VAR_DECL)
8974 [t]he initialization (and any associated
8975 side-effects) of a static data member does
8976 not occur unless the static data member is
8977 itself used in a way that requires the
8978 definition of the static data member to
8981 Therefore, we do not substitute into the
8982 initialized for the static data member here. */
8983 finish_static_data_member_decl
8986 /*init_const_expr_p=*/false,
8987 /*asmspec_tree=*/NULL_TREE,
8989 /* Instantiate members marked with attribute used. */
8990 if (r != error_mark_node && DECL_PRESERVE_P (r))
8993 else if (TREE_CODE (r) == FIELD_DECL)
8995 /* Determine whether R has a valid type and can be
8996 completed later. If R is invalid, then it is
8997 replaced by error_mark_node so that it will not be
8998 added to TYPE_FIELDS. */
8999 tree rtype = TREE_TYPE (r);
9000 if (can_complete_type_without_circularity (rtype))
9001 complete_type (rtype);
9003 if (!COMPLETE_TYPE_P (rtype))
9005 cxx_incomplete_type_error (r, rtype);
9006 r = error_mark_node;
9010 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
9011 such a thing will already have been added to the field
9012 list by tsubst_enum in finish_member_declaration in the
9013 CLASSTYPE_NESTED_UTDS case above. */
9014 if (!(TREE_CODE (r) == TYPE_DECL
9015 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
9016 && DECL_ARTIFICIAL (r)))
9018 set_current_access_from_decl (r);
9019 finish_member_declaration (r);
9026 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
9028 /* Build new CLASSTYPE_FRIEND_CLASSES. */
9030 tree friend_type = t;
9031 bool adjust_processing_template_decl = false;
9033 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
9035 /* template <class T> friend class C; */
9036 friend_type = tsubst_friend_class (friend_type, args);
9037 adjust_processing_template_decl = true;
9039 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
9041 /* template <class T> friend class C::D; */
9042 friend_type = tsubst (friend_type, args,
9043 tf_warning_or_error, NULL_TREE);
9044 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
9045 friend_type = TREE_TYPE (friend_type);
9046 adjust_processing_template_decl = true;
9048 else if (TREE_CODE (friend_type) == TYPENAME_TYPE
9049 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
9051 /* This could be either
9055 when dependent_type_p is false or
9057 template <class U> friend class T::C;
9060 friend_type = tsubst (friend_type, args,
9061 tf_warning_or_error, NULL_TREE);
9062 /* Bump processing_template_decl for correct
9063 dependent_type_p calculation. */
9064 ++processing_template_decl;
9065 if (dependent_type_p (friend_type))
9066 adjust_processing_template_decl = true;
9067 --processing_template_decl;
9069 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
9070 && hidden_name_p (TYPE_NAME (friend_type)))
9074 where C hasn't been declared yet. Let's lookup name
9075 from namespace scope directly, bypassing any name that
9076 come from dependent base class. */
9077 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
9079 /* The call to xref_tag_from_type does injection for friend
9081 push_nested_namespace (ns);
9083 xref_tag_from_type (friend_type, NULL_TREE,
9084 /*tag_scope=*/ts_current);
9085 pop_nested_namespace (ns);
9087 else if (uses_template_parms (friend_type))
9088 /* friend class C<T>; */
9089 friend_type = tsubst (friend_type, args,
9090 tf_warning_or_error, NULL_TREE);
9095 where C is already declared or
9097 friend class C<int>;
9099 We don't have to do anything in these cases. */
9101 if (adjust_processing_template_decl)
9102 /* Trick make_friend_class into realizing that the friend
9103 we're adding is a template, not an ordinary class. It's
9104 important that we use make_friend_class since it will
9105 perform some error-checking and output cross-reference
9107 ++processing_template_decl;
9109 if (friend_type != error_mark_node)
9110 make_friend_class (type, friend_type, /*complain=*/false);
9112 if (adjust_processing_template_decl)
9113 --processing_template_decl;
9117 /* Build new DECL_FRIENDLIST. */
9120 /* The file and line for this declaration, to
9121 assist in error message reporting. Since we
9122 called push_tinst_level above, we don't need to
9124 input_location = DECL_SOURCE_LOCATION (t);
9126 if (TREE_CODE (t) == TEMPLATE_DECL)
9128 ++processing_template_decl;
9129 push_deferring_access_checks (dk_no_check);
9132 r = tsubst_friend_function (t, args);
9133 add_friend (type, r, /*complain=*/false);
9134 if (TREE_CODE (t) == TEMPLATE_DECL)
9136 pop_deferring_access_checks ();
9137 --processing_template_decl;
9143 if (CLASSTYPE_LAMBDA_EXPR (type))
9145 tree decl = lambda_function (type);
9148 tree lambda = CLASSTYPE_LAMBDA_EXPR (type);
9149 if (LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (lambda))
9151 apply_lambda_return_type (lambda, void_type_node);
9152 LAMBDA_EXPR_RETURN_TYPE (lambda) = NULL_TREE;
9154 instantiate_decl (decl, false, false);
9155 maybe_add_lambda_conv_op (type);
9158 gcc_assert (errorcount);
9161 /* Set the file and line number information to whatever is given for
9162 the class itself. This puts error messages involving generated
9163 implicit functions at a predictable point, and the same point
9164 that would be used for non-template classes. */
9165 input_location = DECL_SOURCE_LOCATION (typedecl);
9167 unreverse_member_declarations (type);
9168 finish_struct_1 (type);
9169 TYPE_BEING_DEFINED (type) = 0;
9171 /* We don't instantiate default arguments for member functions. 14.7.1:
9173 The implicit instantiation of a class template specialization causes
9174 the implicit instantiation of the declarations, but not of the
9175 definitions or default arguments, of the class member functions,
9176 member classes, static data members and member templates.... */
9178 /* Some typedefs referenced from within the template code need to be access
9179 checked at template instantiation time, i.e now. These types were
9180 added to the template at parsing time. Let's get those and perform
9181 the access checks then. */
9182 perform_typedefs_access_check (pattern, args);
9183 perform_deferred_access_checks ();
9184 pop_nested_class ();
9185 maximum_field_alignment = saved_maximum_field_alignment;
9186 pop_from_top_level ();
9187 pop_deferring_access_checks ();
9190 /* The vtable for a template class can be emitted in any translation
9191 unit in which the class is instantiated. When there is no key
9192 method, however, finish_struct_1 will already have added TYPE to
9193 the keyed_classes list. */
9194 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
9195 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
9200 /* Wrapper for instantiate_class_template_1. */
9203 instantiate_class_template (tree type)
9206 timevar_push (TV_TEMPLATE_INST);
9207 ret = instantiate_class_template_1 (type);
9208 timevar_pop (TV_TEMPLATE_INST);
9213 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9219 else if (TYPE_P (t))
9220 r = tsubst (t, args, complain, in_decl);
9223 if (!(complain & tf_warning))
9224 ++c_inhibit_evaluation_warnings;
9225 r = tsubst_expr (t, args, complain, in_decl,
9226 /*integral_constant_expression_p=*/true);
9227 if (!(complain & tf_warning))
9228 --c_inhibit_evaluation_warnings;
9229 /* Preserve the raw-reference nature of T. */
9230 if (TREE_TYPE (t) && TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE
9231 && REFERENCE_REF_P (r))
9232 r = TREE_OPERAND (r, 0);
9237 /* Given a function parameter pack TMPL_PARM and some function parameters
9238 instantiated from it at *SPEC_P, return a NONTYPE_ARGUMENT_PACK of them
9239 and set *SPEC_P to point at the next point in the list. */
9242 extract_fnparm_pack (tree tmpl_parm, tree *spec_p)
9244 /* Collect all of the extra "packed" parameters into an
9248 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
9249 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
9250 tree spec_parm = *spec_p;
9253 for (len = 0; spec_parm; ++len, spec_parm = TREE_CHAIN (spec_parm))
9255 && !function_parameter_expanded_from_pack_p (spec_parm, tmpl_parm))
9258 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
9259 parmvec = make_tree_vec (len);
9260 parmtypevec = make_tree_vec (len);
9261 spec_parm = *spec_p;
9262 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
9264 TREE_VEC_ELT (parmvec, i) = spec_parm;
9265 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
9268 /* Build the argument packs. */
9269 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
9270 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
9271 TREE_TYPE (argpack) = argtypepack;
9272 *spec_p = spec_parm;
9277 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
9278 NONTYPE_ARGUMENT_PACK. */
9281 make_fnparm_pack (tree spec_parm)
9283 return extract_fnparm_pack (NULL_TREE, &spec_parm);
9286 /* Substitute ARGS into T, which is an pack expansion
9287 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
9288 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
9289 (if only a partial substitution could be performed) or
9290 ERROR_MARK_NODE if there was an error. */
9292 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
9296 tree pack, packs = NULL_TREE;
9297 bool unsubstituted_packs = false;
9298 bool real_packs = false;
9299 int missing_level = 0;
9302 htab_t saved_local_specializations = NULL;
9303 bool need_local_specializations = false;
9306 gcc_assert (PACK_EXPANSION_P (t));
9307 pattern = PACK_EXPANSION_PATTERN (t);
9309 /* Add in any args remembered from an earlier partial instantiation. */
9310 args = add_to_template_args (PACK_EXPANSION_EXTRA_ARGS (t), args);
9312 levels = TMPL_ARGS_DEPTH (args);
9314 /* Determine the argument packs that will instantiate the parameter
9315 packs used in the expansion expression. While we're at it,
9316 compute the number of arguments to be expanded and make sure it
9318 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
9319 pack = TREE_CHAIN (pack))
9321 tree parm_pack = TREE_VALUE (pack);
9322 tree arg_pack = NULL_TREE;
9323 tree orig_arg = NULL_TREE;
9326 if (TREE_CODE (parm_pack) == BASES)
9328 if (BASES_DIRECT (parm_pack))
9329 return calculate_direct_bases (tsubst_expr (BASES_TYPE (parm_pack),
9330 args, complain, in_decl, false));
9332 return calculate_bases (tsubst_expr (BASES_TYPE (parm_pack),
9333 args, complain, in_decl, false));
9335 if (TREE_CODE (parm_pack) == PARM_DECL)
9337 if (at_function_scope_p ())
9338 arg_pack = retrieve_local_specialization (parm_pack);
9341 /* We can't rely on local_specializations for a parameter
9342 name used later in a function declaration (such as in a
9343 late-specified return type). Even if it exists, it might
9344 have the wrong value for a recursive call. Just make a
9345 dummy decl, since it's only used for its type. */
9346 arg_pack = tsubst_decl (parm_pack, args, complain);
9347 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
9348 /* Partial instantiation of the parm_pack, we can't build
9349 up an argument pack yet. */
9350 arg_pack = NULL_TREE;
9352 arg_pack = make_fnparm_pack (arg_pack);
9353 need_local_specializations = true;
9359 template_parm_level_and_index (parm_pack, &level, &idx);
9361 if (level <= levels)
9362 arg_pack = TMPL_ARG (args, level, idx);
9365 orig_arg = arg_pack;
9366 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
9367 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
9369 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
9370 /* This can only happen if we forget to expand an argument
9371 pack somewhere else. Just return an error, silently. */
9373 result = make_tree_vec (1);
9374 TREE_VEC_ELT (result, 0) = error_mark_node;
9378 if (arg_from_parm_pack_p (arg_pack, parm_pack))
9379 /* The argument pack that the parameter maps to is just an
9380 expansion of the parameter itself, such as one would find
9381 in the implicit typedef of a class inside the class itself.
9382 Consider this parameter "unsubstituted", so that we will
9383 maintain the outer pack expansion. */
9384 arg_pack = NULL_TREE;
9389 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
9391 /* Don't bother trying to do a partial substitution with
9392 incomplete packs; we'll try again after deduction. */
9393 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
9398 else if (len != my_len)
9400 if (!(complain & tf_error))
9401 /* Fail quietly. */;
9402 else if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
9403 error ("mismatched argument pack lengths while expanding "
9407 error ("mismatched argument pack lengths while expanding "
9410 return error_mark_node;
9413 if (TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
9414 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack),
9416 /* This isn't a real argument pack yet. */;
9420 /* Keep track of the parameter packs and their corresponding
9422 packs = tree_cons (parm_pack, arg_pack, packs);
9423 TREE_TYPE (packs) = orig_arg;
9427 /* We can't substitute for this parameter pack. We use a flag as
9428 well as the missing_level counter because function parameter
9429 packs don't have a level. */
9430 unsubstituted_packs = true;
9431 if (!missing_level || missing_level > level)
9432 missing_level = level;
9436 /* We cannot expand this expansion expression, because we don't have
9437 all of the argument packs we need. */
9438 if (unsubstituted_packs)
9442 /* We got some full packs, but we can't substitute them in until we
9443 have values for all the packs. So remember these until then. */
9446 t = make_pack_expansion (pattern);
9448 /* The call to add_to_template_args above assumes no overlap
9449 between saved args and new args, so prune away any fake
9450 args, i.e. those that satisfied arg_from_parm_pack_p above. */
9451 if (missing_level && levels >= missing_level)
9453 gcc_assert (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args)
9454 && missing_level > 1);
9455 TREE_VEC_LENGTH (args) = missing_level - 1;
9456 save_args = copy_node (args);
9457 TREE_VEC_LENGTH (args) = levels;
9462 PACK_EXPANSION_EXTRA_ARGS (t) = save_args;
9466 /* There were no real arguments, we're just replacing a parameter
9467 pack with another version of itself. Substitute into the
9468 pattern and return a PACK_EXPANSION_*. The caller will need to
9470 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9471 t = tsubst_expr (pattern, args, complain, in_decl,
9472 /*integral_constant_expression_p=*/false);
9474 t = tsubst (pattern, args, complain, in_decl);
9475 t = make_pack_expansion (t);
9480 /* We could not find any argument packs that work. */
9482 return error_mark_node;
9484 if (need_local_specializations)
9486 /* We're in a late-specified return type, so create our own local
9487 specializations table; the current table is either NULL or (in the
9488 case of recursive unification) might have bindings that we don't
9489 want to use or alter. */
9490 saved_local_specializations = local_specializations;
9491 local_specializations = htab_create (37,
9492 hash_local_specialization,
9493 eq_local_specializations,
9497 /* For each argument in each argument pack, substitute into the
9499 result = make_tree_vec (len);
9500 for (i = 0; i < len; ++i)
9502 /* For parameter pack, change the substitution of the parameter
9503 pack to the ith argument in its argument pack, then expand
9505 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9507 tree parm = TREE_PURPOSE (pack);
9510 /* Select the Ith argument from the pack. */
9511 if (TREE_CODE (parm) == PARM_DECL)
9515 arg = make_node (ARGUMENT_PACK_SELECT);
9516 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9518 register_local_specialization (arg, parm);
9521 arg = retrieve_local_specialization (parm);
9526 template_parm_level_and_index (parm, &level, &idx);
9530 arg = make_node (ARGUMENT_PACK_SELECT);
9531 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9532 /* Update the corresponding argument. */
9533 TMPL_ARG (args, level, idx) = arg;
9536 /* Re-use the ARGUMENT_PACK_SELECT. */
9537 arg = TMPL_ARG (args, level, idx);
9539 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
9542 /* Substitute into the PATTERN with the altered arguments. */
9543 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9544 TREE_VEC_ELT (result, i) =
9545 tsubst_expr (pattern, args, complain, in_decl,
9546 /*integral_constant_expression_p=*/false);
9548 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
9550 if (TREE_VEC_ELT (result, i) == error_mark_node)
9552 result = error_mark_node;
9557 /* Update ARGS to restore the substitution from parameter packs to
9558 their argument packs. */
9559 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9561 tree parm = TREE_PURPOSE (pack);
9563 if (TREE_CODE (parm) == PARM_DECL)
9564 register_local_specialization (TREE_TYPE (pack), parm);
9568 template_parm_level_and_index (parm, &level, &idx);
9570 /* Update the corresponding argument. */
9571 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
9572 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
9575 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
9579 if (saved_local_specializations)
9581 htab_delete (local_specializations);
9582 local_specializations = saved_local_specializations;
9588 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
9589 TMPL. We do this using DECL_PARM_INDEX, which should work even with
9590 parameter packs; all parms generated from a function parameter pack will
9591 have the same DECL_PARM_INDEX. */
9594 get_pattern_parm (tree parm, tree tmpl)
9596 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
9599 if (DECL_ARTIFICIAL (parm))
9601 for (patparm = DECL_ARGUMENTS (pattern);
9602 patparm; patparm = DECL_CHAIN (patparm))
9603 if (DECL_ARTIFICIAL (patparm)
9604 && DECL_NAME (parm) == DECL_NAME (patparm))
9609 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
9610 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
9611 gcc_assert (DECL_PARM_INDEX (patparm)
9612 == DECL_PARM_INDEX (parm));
9618 /* Substitute ARGS into the vector or list of template arguments T. */
9621 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9624 int len, need_new = 0, i, expanded_len_adjust = 0, out;
9627 if (t == error_mark_node)
9628 return error_mark_node;
9630 len = TREE_VEC_LENGTH (t);
9631 elts = XALLOCAVEC (tree, len);
9633 for (i = 0; i < len; i++)
9635 tree orig_arg = TREE_VEC_ELT (t, i);
9638 if (TREE_CODE (orig_arg) == TREE_VEC)
9639 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9640 else if (PACK_EXPANSION_P (orig_arg))
9642 /* Substitute into an expansion expression. */
9643 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9645 if (TREE_CODE (new_arg) == TREE_VEC)
9646 /* Add to the expanded length adjustment the number of
9647 expanded arguments. We subtract one from this
9648 measurement, because the argument pack expression
9649 itself is already counted as 1 in
9650 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9651 the argument pack is empty. */
9652 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9654 else if (ARGUMENT_PACK_P (orig_arg))
9656 /* Substitute into each of the arguments. */
9657 new_arg = TYPE_P (orig_arg)
9658 ? cxx_make_type (TREE_CODE (orig_arg))
9659 : make_node (TREE_CODE (orig_arg));
9661 SET_ARGUMENT_PACK_ARGS (
9663 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9664 args, complain, in_decl));
9666 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9667 new_arg = error_mark_node;
9669 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9670 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9672 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9674 if (TREE_TYPE (new_arg) == error_mark_node)
9675 new_arg = error_mark_node;
9679 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9681 if (new_arg == error_mark_node)
9682 return error_mark_node;
9685 if (new_arg != orig_arg)
9692 /* Make space for the expanded arguments coming from template
9694 t = make_tree_vec (len + expanded_len_adjust);
9695 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9696 arguments for a member template.
9697 In that case each TREE_VEC in ORIG_T represents a level of template
9698 arguments, and ORIG_T won't carry any non defaulted argument count.
9699 It will rather be the nested TREE_VECs that will carry one.
9700 In other words, ORIG_T carries a non defaulted argument count only
9701 if it doesn't contain any nested TREE_VEC. */
9702 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9704 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9705 count += expanded_len_adjust;
9706 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9708 for (i = 0, out = 0; i < len; i++)
9710 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9711 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9712 && TREE_CODE (elts[i]) == TREE_VEC)
9716 /* Now expand the template argument pack "in place". */
9717 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9718 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9722 TREE_VEC_ELT (t, out) = elts[i];
9730 /* Return the result of substituting ARGS into the template parameters
9731 given by PARMS. If there are m levels of ARGS and m + n levels of
9732 PARMS, then the result will contain n levels of PARMS. For
9733 example, if PARMS is `template <class T> template <class U>
9734 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9735 result will be `template <int*, double, class V>'. */
9738 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9743 /* When substituting into a template, we must set
9744 PROCESSING_TEMPLATE_DECL as the template parameters may be
9745 dependent if they are based on one-another, and the dependency
9746 predicates are short-circuit outside of templates. */
9747 ++processing_template_decl;
9749 for (new_parms = &r;
9750 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9751 new_parms = &(TREE_CHAIN (*new_parms)),
9752 parms = TREE_CHAIN (parms))
9755 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9758 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9762 if (parms == error_mark_node)
9765 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9767 if (tuple == error_mark_node)
9770 TREE_VEC_ELT (new_vec, i) =
9771 tsubst_template_parm (tuple, args, complain);
9775 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9776 - TMPL_ARGS_DEPTH (args)),
9777 new_vec, NULL_TREE);
9780 --processing_template_decl;
9785 /* Return the result of substituting ARGS into one template parameter
9786 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9787 parameter and which TREE_PURPOSE is the default argument of the
9788 template parameter. */
9791 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9793 tree default_value, parm_decl;
9795 if (args == NULL_TREE
9797 || t == error_mark_node)
9800 gcc_assert (TREE_CODE (t) == TREE_LIST);
9802 default_value = TREE_PURPOSE (t);
9803 parm_decl = TREE_VALUE (t);
9805 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9806 if (TREE_CODE (parm_decl) == PARM_DECL
9807 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9808 parm_decl = error_mark_node;
9809 default_value = tsubst_template_arg (default_value, args,
9810 complain, NULL_TREE);
9812 return build_tree_list (default_value, parm_decl);
9815 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9816 type T. If T is not an aggregate or enumeration type, it is
9817 handled as if by tsubst. IN_DECL is as for tsubst. If
9818 ENTERING_SCOPE is nonzero, T is the context for a template which
9819 we are presently tsubst'ing. Return the substituted value. */
9822 tsubst_aggr_type (tree t,
9824 tsubst_flags_t complain,
9831 switch (TREE_CODE (t))
9834 if (TYPE_PTRMEMFUNC_P (t))
9835 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9837 /* Else fall through. */
9840 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9845 int saved_unevaluated_operand;
9846 int saved_inhibit_evaluation_warnings;
9848 /* In "sizeof(X<I>)" we need to evaluate "I". */
9849 saved_unevaluated_operand = cp_unevaluated_operand;
9850 cp_unevaluated_operand = 0;
9851 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9852 c_inhibit_evaluation_warnings = 0;
9854 /* First, determine the context for the type we are looking
9856 context = TYPE_CONTEXT (t);
9857 if (context && TYPE_P (context))
9859 context = tsubst_aggr_type (context, args, complain,
9860 in_decl, /*entering_scope=*/1);
9861 /* If context is a nested class inside a class template,
9862 it may still need to be instantiated (c++/33959). */
9863 context = complete_type (context);
9866 /* Then, figure out what arguments are appropriate for the
9867 type we are trying to find. For example, given:
9869 template <class T> struct S;
9870 template <class T, class U> void f(T, U) { S<U> su; }
9872 and supposing that we are instantiating f<int, double>,
9873 then our ARGS will be {int, double}, but, when looking up
9874 S we only want {double}. */
9875 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9877 if (argvec == error_mark_node)
9878 r = error_mark_node;
9881 r = lookup_template_class (t, argvec, in_decl, context,
9882 entering_scope, complain);
9883 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9886 cp_unevaluated_operand = saved_unevaluated_operand;
9887 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9892 /* This is not a template type, so there's nothing to do. */
9896 return tsubst (t, args, complain, in_decl);
9900 /* Substitute into the default argument ARG (a default argument for
9901 FN), which has the indicated TYPE. */
9904 tsubst_default_argument (tree fn, tree type, tree arg)
9906 tree saved_class_ptr = NULL_TREE;
9907 tree saved_class_ref = NULL_TREE;
9909 /* This can happen in invalid code. */
9910 if (TREE_CODE (arg) == DEFAULT_ARG)
9913 /* This default argument came from a template. Instantiate the
9914 default argument here, not in tsubst. In the case of
9923 we must be careful to do name lookup in the scope of S<T>,
9924 rather than in the current class. */
9925 push_access_scope (fn);
9926 /* The "this" pointer is not valid in a default argument. */
9929 saved_class_ptr = current_class_ptr;
9930 cp_function_chain->x_current_class_ptr = NULL_TREE;
9931 saved_class_ref = current_class_ref;
9932 cp_function_chain->x_current_class_ref = NULL_TREE;
9935 push_deferring_access_checks(dk_no_deferred);
9936 /* The default argument expression may cause implicitly defined
9937 member functions to be synthesized, which will result in garbage
9938 collection. We must treat this situation as if we were within
9939 the body of function so as to avoid collecting live data on the
9942 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9943 tf_warning_or_error, NULL_TREE,
9944 /*integral_constant_expression_p=*/false);
9946 pop_deferring_access_checks();
9948 /* Restore the "this" pointer. */
9951 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9952 cp_function_chain->x_current_class_ref = saved_class_ref;
9955 /* Make sure the default argument is reasonable. */
9956 arg = check_default_argument (type, arg);
9958 pop_access_scope (fn);
9963 /* Substitute into all the default arguments for FN. */
9966 tsubst_default_arguments (tree fn)
9971 tmpl_args = DECL_TI_ARGS (fn);
9973 /* If this function is not yet instantiated, we certainly don't need
9974 its default arguments. */
9975 if (uses_template_parms (tmpl_args))
9977 /* Don't do this again for clones. */
9978 if (DECL_CLONED_FUNCTION_P (fn))
9981 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
9983 arg = TREE_CHAIN (arg))
9984 if (TREE_PURPOSE (arg))
9985 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
9987 TREE_PURPOSE (arg));
9990 /* Substitute the ARGS into the T, which is a _DECL. Return the
9991 result of the substitution. Issue error and warning messages under
9992 control of COMPLAIN. */
9995 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
9997 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
9998 location_t saved_loc;
10001 hashval_t hash = 0;
10003 /* Set the filename and linenumber to improve error-reporting. */
10004 saved_loc = input_location;
10005 input_location = DECL_SOURCE_LOCATION (t);
10007 switch (TREE_CODE (t))
10009 case TEMPLATE_DECL:
10011 /* We can get here when processing a member function template,
10012 member class template, or template template parameter. */
10013 tree decl = DECL_TEMPLATE_RESULT (t);
10018 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
10020 /* Template template parameter is treated here. */
10021 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10022 if (new_type == error_mark_node)
10023 RETURN (error_mark_node);
10026 DECL_CHAIN (r) = NULL_TREE;
10027 TREE_TYPE (r) = new_type;
10028 DECL_TEMPLATE_RESULT (r)
10029 = build_decl (DECL_SOURCE_LOCATION (decl),
10030 TYPE_DECL, DECL_NAME (decl), new_type);
10031 DECL_TEMPLATE_PARMS (r)
10032 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10034 TYPE_NAME (new_type) = r;
10038 /* We might already have an instance of this template.
10039 The ARGS are for the surrounding class type, so the
10040 full args contain the tsubst'd args for the context,
10041 plus the innermost args from the template decl. */
10042 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
10043 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
10044 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
10045 /* Because this is a template, the arguments will still be
10046 dependent, even after substitution. If
10047 PROCESSING_TEMPLATE_DECL is not set, the dependency
10048 predicates will short-circuit. */
10049 ++processing_template_decl;
10050 full_args = tsubst_template_args (tmpl_args, args,
10051 complain, in_decl);
10052 --processing_template_decl;
10053 if (full_args == error_mark_node)
10054 RETURN (error_mark_node);
10056 /* If this is a default template template argument,
10057 tsubst might not have changed anything. */
10058 if (full_args == tmpl_args)
10061 hash = hash_tmpl_and_args (t, full_args);
10062 spec = retrieve_specialization (t, full_args, hash);
10063 if (spec != NULL_TREE)
10069 /* Make a new template decl. It will be similar to the
10070 original, but will record the current template arguments.
10071 We also create a new function declaration, which is just
10072 like the old one, but points to this new template, rather
10073 than the old one. */
10075 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
10076 DECL_CHAIN (r) = NULL_TREE;
10078 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10080 if (TREE_CODE (decl) == TYPE_DECL
10081 && !TYPE_DECL_ALIAS_P (decl))
10084 ++processing_template_decl;
10085 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10086 --processing_template_decl;
10087 if (new_type == error_mark_node)
10088 RETURN (error_mark_node);
10090 TREE_TYPE (r) = new_type;
10091 CLASSTYPE_TI_TEMPLATE (new_type) = r;
10092 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
10093 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
10094 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
10099 ++processing_template_decl;
10100 new_decl = tsubst (decl, args, complain, in_decl);
10101 --processing_template_decl;
10102 if (new_decl == error_mark_node)
10103 RETURN (error_mark_node);
10105 DECL_TEMPLATE_RESULT (r) = new_decl;
10106 DECL_TI_TEMPLATE (new_decl) = r;
10107 TREE_TYPE (r) = TREE_TYPE (new_decl);
10108 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
10109 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
10112 SET_DECL_IMPLICIT_INSTANTIATION (r);
10113 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
10114 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
10116 /* The template parameters for this new template are all the
10117 template parameters for the old template, except the
10118 outermost level of parameters. */
10119 DECL_TEMPLATE_PARMS (r)
10120 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10123 if (PRIMARY_TEMPLATE_P (t))
10124 DECL_PRIMARY_TEMPLATE (r) = r;
10126 if (TREE_CODE (decl) != TYPE_DECL)
10127 /* Record this non-type partial instantiation. */
10128 register_specialization (r, t,
10129 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
10134 case FUNCTION_DECL:
10137 tree argvec = NULL_TREE;
10145 /* Nobody should be tsubst'ing into non-template functions. */
10146 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
10148 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
10153 /* If T is not dependent, just return it. We have to
10154 increment PROCESSING_TEMPLATE_DECL because
10155 value_dependent_expression_p assumes that nothing is
10156 dependent when PROCESSING_TEMPLATE_DECL is zero. */
10157 ++processing_template_decl;
10158 dependent_p = value_dependent_expression_p (t);
10159 --processing_template_decl;
10163 /* Calculate the most general template of which R is a
10164 specialization, and the complete set of arguments used to
10166 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
10167 argvec = tsubst_template_args (DECL_TI_ARGS
10168 (DECL_TEMPLATE_RESULT
10169 (DECL_TI_TEMPLATE (t))),
10170 args, complain, in_decl);
10171 if (argvec == error_mark_node)
10172 RETURN (error_mark_node);
10174 /* Check to see if we already have this specialization. */
10175 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10176 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10184 /* We can see more levels of arguments than parameters if
10185 there was a specialization of a member template, like
10188 template <class T> struct S { template <class U> void f(); }
10189 template <> template <class U> void S<int>::f(U);
10191 Here, we'll be substituting into the specialization,
10192 because that's where we can find the code we actually
10193 want to generate, but we'll have enough arguments for
10194 the most general template.
10196 We also deal with the peculiar case:
10198 template <class T> struct S {
10199 template <class U> friend void f();
10201 template <class U> void f() {}
10203 template void f<double>();
10205 Here, the ARGS for the instantiation of will be {int,
10206 double}. But, we only need as many ARGS as there are
10207 levels of template parameters in CODE_PATTERN. We are
10208 careful not to get fooled into reducing the ARGS in
10211 template <class T> struct S { template <class U> void f(U); }
10212 template <class T> template <> void S<T>::f(int) {}
10214 which we can spot because the pattern will be a
10215 specialization in this case. */
10216 args_depth = TMPL_ARGS_DEPTH (args);
10218 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
10219 if (args_depth > parms_depth
10220 && !DECL_TEMPLATE_SPECIALIZATION (t))
10221 args = get_innermost_template_args (args, parms_depth);
10225 /* This special case arises when we have something like this:
10227 template <class T> struct S {
10228 friend void f<int>(int, double);
10231 Here, the DECL_TI_TEMPLATE for the friend declaration
10232 will be an IDENTIFIER_NODE. We are being called from
10233 tsubst_friend_function, and we want only to create a
10234 new decl (R) with appropriate types so that we can call
10235 determine_specialization. */
10236 gen_tmpl = NULL_TREE;
10239 if (DECL_CLASS_SCOPE_P (t))
10241 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
10245 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
10246 complain, t, /*entering_scope=*/1);
10251 ctx = DECL_CONTEXT (t);
10253 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10254 if (type == error_mark_node)
10255 RETURN (error_mark_node);
10257 /* We do NOT check for matching decls pushed separately at this
10258 point, as they may not represent instantiations of this
10259 template, and in any case are considered separate under the
10262 DECL_USE_TEMPLATE (r) = 0;
10263 TREE_TYPE (r) = type;
10264 /* Clear out the mangled name and RTL for the instantiation. */
10265 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10266 SET_DECL_RTL (r, NULL);
10267 /* Leave DECL_INITIAL set on deleted instantiations. */
10268 if (!DECL_DELETED_FN (r))
10269 DECL_INITIAL (r) = NULL_TREE;
10270 DECL_CONTEXT (r) = ctx;
10272 if (member && DECL_CONV_FN_P (r))
10273 /* Type-conversion operator. Reconstruct the name, in
10274 case it's the name of one of the template's parameters. */
10275 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
10277 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
10279 DECL_RESULT (r) = NULL_TREE;
10281 TREE_STATIC (r) = 0;
10282 TREE_PUBLIC (r) = TREE_PUBLIC (t);
10283 DECL_EXTERNAL (r) = 1;
10284 /* If this is an instantiation of a function with internal
10285 linkage, we already know what object file linkage will be
10286 assigned to the instantiation. */
10287 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
10288 DECL_DEFER_OUTPUT (r) = 0;
10289 DECL_CHAIN (r) = NULL_TREE;
10290 DECL_PENDING_INLINE_INFO (r) = 0;
10291 DECL_PENDING_INLINE_P (r) = 0;
10292 DECL_SAVED_TREE (r) = NULL_TREE;
10293 DECL_STRUCT_FUNCTION (r) = NULL;
10295 /* We'll re-clone as appropriate in instantiate_template. */
10296 DECL_CLONED_FUNCTION (r) = NULL_TREE;
10298 /* If we aren't complaining now, return on error before we register
10299 the specialization so that we'll complain eventually. */
10300 if ((complain & tf_error) == 0
10301 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10302 && !grok_op_properties (r, /*complain=*/false))
10303 RETURN (error_mark_node);
10305 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
10306 this in the special friend case mentioned above where
10307 GEN_TMPL is NULL. */
10310 DECL_TEMPLATE_INFO (r)
10311 = build_template_info (gen_tmpl, argvec);
10312 SET_DECL_IMPLICIT_INSTANTIATION (r);
10313 register_specialization (r, gen_tmpl, argvec, false, hash);
10315 /* We're not supposed to instantiate default arguments
10316 until they are called, for a template. But, for a
10319 template <class T> void f ()
10320 { extern void g(int i = T()); }
10322 we should do the substitution when the template is
10323 instantiated. We handle the member function case in
10324 instantiate_class_template since the default arguments
10325 might refer to other members of the class. */
10327 && !PRIMARY_TEMPLATE_P (gen_tmpl)
10328 && !uses_template_parms (argvec))
10329 tsubst_default_arguments (r);
10332 DECL_TEMPLATE_INFO (r) = NULL_TREE;
10334 /* Copy the list of befriending classes. */
10335 for (friends = &DECL_BEFRIENDING_CLASSES (r);
10337 friends = &TREE_CHAIN (*friends))
10339 *friends = copy_node (*friends);
10340 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
10345 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
10347 maybe_retrofit_in_chrg (r);
10348 if (DECL_CONSTRUCTOR_P (r))
10349 grok_ctor_properties (ctx, r);
10350 /* If this is an instantiation of a member template, clone it.
10351 If it isn't, that'll be handled by
10352 clone_constructors_and_destructors. */
10353 if (PRIMARY_TEMPLATE_P (gen_tmpl))
10354 clone_function_decl (r, /*update_method_vec_p=*/0);
10356 else if ((complain & tf_error) != 0
10357 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10358 && !grok_op_properties (r, /*complain=*/true))
10359 RETURN (error_mark_node);
10361 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
10362 SET_DECL_FRIEND_CONTEXT (r,
10363 tsubst (DECL_FRIEND_CONTEXT (t),
10364 args, complain, in_decl));
10366 /* Possibly limit visibility based on template args. */
10367 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10368 if (DECL_VISIBILITY_SPECIFIED (t))
10370 DECL_VISIBILITY_SPECIFIED (r) = 0;
10371 DECL_ATTRIBUTES (r)
10372 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10374 determine_visibility (r);
10375 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
10376 && !processing_template_decl)
10377 defaulted_late_check (r);
10379 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10380 args, complain, in_decl);
10386 tree type = NULL_TREE;
10388 tree expanded_types = NULL_TREE;
10389 tree prev_r = NULL_TREE;
10390 tree first_r = NULL_TREE;
10392 if (FUNCTION_PARAMETER_PACK_P (t))
10394 /* If there is a local specialization that isn't a
10395 parameter pack, it means that we're doing a "simple"
10396 substitution from inside tsubst_pack_expansion. Just
10397 return the local specialization (which will be a single
10399 tree spec = retrieve_local_specialization (t);
10401 && TREE_CODE (spec) == PARM_DECL
10402 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
10405 /* Expand the TYPE_PACK_EXPANSION that provides the types for
10406 the parameters in this function parameter pack. */
10407 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
10408 complain, in_decl);
10409 if (TREE_CODE (expanded_types) == TREE_VEC)
10411 len = TREE_VEC_LENGTH (expanded_types);
10413 /* Zero-length parameter packs are boring. Just substitute
10416 RETURN (tsubst (TREE_CHAIN (t), args, complain,
10421 /* All we did was update the type. Make a note of that. */
10422 type = expanded_types;
10423 expanded_types = NULL_TREE;
10427 /* Loop through all of the parameter's we'll build. When T is
10428 a function parameter pack, LEN is the number of expanded
10429 types in EXPANDED_TYPES; otherwise, LEN is 1. */
10431 for (i = 0; i < len; ++i)
10435 if (DECL_TEMPLATE_PARM_P (t))
10436 SET_DECL_TEMPLATE_PARM_P (r);
10438 if (expanded_types)
10439 /* We're on the Ith parameter of the function parameter
10442 /* An argument of a function parameter pack is not a parameter
10444 FUNCTION_PARAMETER_PACK_P (r) = false;
10446 /* Get the Ith type. */
10447 type = TREE_VEC_ELT (expanded_types, i);
10450 /* Rename the parameter to include the index. */
10452 make_ith_pack_parameter_name (DECL_NAME (r), i);
10455 /* We're dealing with a normal parameter. */
10456 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10458 type = type_decays_to (type);
10459 TREE_TYPE (r) = type;
10460 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10462 if (DECL_INITIAL (r))
10464 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
10465 DECL_INITIAL (r) = TREE_TYPE (r);
10467 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
10468 complain, in_decl);
10471 DECL_CONTEXT (r) = NULL_TREE;
10473 if (!DECL_TEMPLATE_PARM_P (r))
10474 DECL_ARG_TYPE (r) = type_passed_as (type);
10476 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10477 args, complain, in_decl);
10479 /* Keep track of the first new parameter we
10480 generate. That's what will be returned to the
10485 /* Build a proper chain of parameters when substituting
10486 into a function parameter pack. */
10488 DECL_CHAIN (prev_r) = r;
10491 if (DECL_CHAIN (t))
10492 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
10493 complain, DECL_CHAIN (t));
10495 /* FIRST_R contains the start of the chain we've built. */
10505 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10506 if (type == error_mark_node)
10507 RETURN (error_mark_node);
10508 TREE_TYPE (r) = type;
10509 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10511 if (DECL_C_BIT_FIELD (r))
10512 /* For bit-fields, DECL_INITIAL gives the number of bits. For
10513 non-bit-fields DECL_INITIAL is a non-static data member
10514 initializer, which gets deferred instantiation. */
10516 = tsubst_expr (DECL_INITIAL (t), args,
10518 /*integral_constant_expression_p=*/true);
10519 else if (DECL_INITIAL (t))
10521 /* Set up DECL_TEMPLATE_INFO so that we can get at the
10522 NSDMI in perform_member_init. Still set DECL_INITIAL
10523 so that we know there is one. */
10524 DECL_INITIAL (r) = void_zero_node;
10525 gcc_assert (DECL_LANG_SPECIFIC (r) == NULL);
10526 retrofit_lang_decl (r);
10527 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10529 /* We don't have to set DECL_CONTEXT here; it is set by
10530 finish_member_declaration. */
10531 DECL_CHAIN (r) = NULL_TREE;
10532 if (VOID_TYPE_P (type))
10533 error ("instantiation of %q+D as type %qT", r, type);
10535 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10536 args, complain, in_decl);
10541 /* We reach here only for member using decls. */
10542 if (DECL_DEPENDENT_P (t))
10544 r = do_class_using_decl
10545 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
10546 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
10548 r = error_mark_node;
10551 TREE_PROTECTED (r) = TREE_PROTECTED (t);
10552 TREE_PRIVATE (r) = TREE_PRIVATE (t);
10558 DECL_CHAIN (r) = NULL_TREE;
10565 tree argvec = NULL_TREE;
10566 tree gen_tmpl = NULL_TREE;
10568 tree tmpl = NULL_TREE;
10570 tree type = NULL_TREE;
10573 if (TREE_CODE (t) == TYPE_DECL
10574 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
10576 /* If this is the canonical decl, we don't have to
10577 mess with instantiations, and often we can't (for
10578 typename, template type parms and such). Note that
10579 TYPE_NAME is not correct for the above test if
10580 we've copied the type for a typedef. */
10581 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10582 if (type == error_mark_node)
10583 RETURN (error_mark_node);
10584 r = TYPE_NAME (type);
10588 /* Check to see if we already have the specialization we
10591 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
10593 /* T is a static data member or namespace-scope entity.
10594 We have to substitute into namespace-scope variables
10595 (even though such entities are never templates) because
10598 template <class T> void f() { extern T t; }
10600 where the entity referenced is not known until
10601 instantiation time. */
10603 ctx = DECL_CONTEXT (t);
10604 if (DECL_CLASS_SCOPE_P (t))
10606 ctx = tsubst_aggr_type (ctx, args,
10608 in_decl, /*entering_scope=*/1);
10609 /* If CTX is unchanged, then T is in fact the
10610 specialization we want. That situation occurs when
10611 referencing a static data member within in its own
10612 class. We can use pointer equality, rather than
10613 same_type_p, because DECL_CONTEXT is always
10615 if (ctx == DECL_CONTEXT (t)
10616 && (TREE_CODE (t) != TYPE_DECL
10617 /* ... unless T is a member template; in which
10618 case our caller can be willing to create a
10619 specialization of that template represented
10621 || !(DECL_TI_TEMPLATE (t)
10622 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (t)))))
10628 tmpl = DECL_TI_TEMPLATE (t);
10629 gen_tmpl = most_general_template (tmpl);
10630 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
10631 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10632 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10637 /* A local variable. */
10639 /* Subsequent calls to pushdecl will fill this in. */
10641 spec = retrieve_local_specialization (t);
10643 /* If we already have the specialization we need, there is
10644 nothing more to do. */
10651 /* Create a new node for the specialization we need. */
10653 if (type == NULL_TREE)
10655 if (is_typedef_decl (t))
10656 type = DECL_ORIGINAL_TYPE (t);
10658 type = TREE_TYPE (t);
10659 if (TREE_CODE (t) == VAR_DECL
10660 && VAR_HAD_UNKNOWN_BOUND (t)
10661 && type != error_mark_node)
10662 type = strip_array_domain (type);
10663 type = tsubst (type, args, complain, in_decl);
10665 if (TREE_CODE (r) == VAR_DECL)
10667 /* Even if the original location is out of scope, the
10668 newly substituted one is not. */
10669 DECL_DEAD_FOR_LOCAL (r) = 0;
10670 DECL_INITIALIZED_P (r) = 0;
10671 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10672 if (type == error_mark_node)
10673 RETURN (error_mark_node);
10674 if (TREE_CODE (type) == FUNCTION_TYPE)
10676 /* It may seem that this case cannot occur, since:
10681 declares a function, not a variable. However:
10684 template <typename T> void g() { T t; }
10685 template void g<f>();
10687 is an attempt to declare a variable with function
10689 error ("variable %qD has function type",
10690 /* R is not yet sufficiently initialized, so we
10691 just use its name. */
10693 RETURN (error_mark_node);
10695 type = complete_type (type);
10696 /* Wait until cp_finish_decl to set this again, to handle
10697 circular dependency (template/instantiate6.C). */
10698 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10699 type = check_var_type (DECL_NAME (r), type);
10701 if (DECL_HAS_VALUE_EXPR_P (t))
10703 tree ve = DECL_VALUE_EXPR (t);
10704 ve = tsubst_expr (ve, args, complain, in_decl,
10705 /*constant_expression_p=*/false);
10706 if (REFERENCE_REF_P (ve))
10708 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
10709 ve = TREE_OPERAND (ve, 0);
10711 SET_DECL_VALUE_EXPR (r, ve);
10714 else if (DECL_SELF_REFERENCE_P (t))
10715 SET_DECL_SELF_REFERENCE_P (r);
10716 TREE_TYPE (r) = type;
10717 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10718 DECL_CONTEXT (r) = ctx;
10719 /* Clear out the mangled name and RTL for the instantiation. */
10720 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10721 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10722 SET_DECL_RTL (r, NULL);
10723 /* The initializer must not be expanded until it is required;
10724 see [temp.inst]. */
10725 DECL_INITIAL (r) = NULL_TREE;
10726 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10727 SET_DECL_RTL (r, NULL);
10728 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10729 if (TREE_CODE (r) == VAR_DECL)
10731 /* Possibly limit visibility based on template args. */
10732 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10733 if (DECL_VISIBILITY_SPECIFIED (t))
10735 DECL_VISIBILITY_SPECIFIED (r) = 0;
10736 DECL_ATTRIBUTES (r)
10737 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10739 determine_visibility (r);
10744 /* A static data member declaration is always marked
10745 external when it is declared in-class, even if an
10746 initializer is present. We mimic the non-template
10747 processing here. */
10748 DECL_EXTERNAL (r) = 1;
10750 register_specialization (r, gen_tmpl, argvec, false, hash);
10751 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10752 SET_DECL_IMPLICIT_INSTANTIATION (r);
10754 else if (cp_unevaluated_operand)
10756 /* We're substituting this var in a decltype outside of its
10757 scope, such as for a lambda return type. Don't add it to
10758 local_specializations, do perform auto deduction. */
10759 tree auto_node = type_uses_auto (type);
10763 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10764 /*constant_expression_p=*/false);
10765 init = resolve_nondeduced_context (init);
10766 TREE_TYPE (r) = type
10767 = do_auto_deduction (type, init, auto_node);
10771 register_local_specialization (r, t);
10773 DECL_CHAIN (r) = NULL_TREE;
10775 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10777 args, complain, in_decl);
10779 /* Preserve a typedef that names a type. */
10780 if (is_typedef_decl (r))
10782 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10783 set_underlying_type (r);
10786 layout_decl (r, 0);
10791 gcc_unreachable ();
10796 /* Restore the file and line information. */
10797 input_location = saved_loc;
10802 /* Substitute into the ARG_TYPES of a function type. */
10805 tsubst_arg_types (tree arg_types,
10807 tsubst_flags_t complain,
10810 tree remaining_arg_types;
10811 tree type = NULL_TREE;
10813 tree expanded_args = NULL_TREE;
10816 if (!arg_types || arg_types == void_list_node)
10819 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10820 args, complain, in_decl);
10821 if (remaining_arg_types == error_mark_node)
10822 return error_mark_node;
10824 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10826 /* For a pack expansion, perform substitution on the
10827 entire expression. Later on, we'll handle the arguments
10829 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10830 args, complain, in_decl);
10832 if (TREE_CODE (expanded_args) == TREE_VEC)
10833 /* So that we'll spin through the parameters, one by one. */
10834 i = TREE_VEC_LENGTH (expanded_args);
10837 /* We only partially substituted into the parameter
10838 pack. Our type is TYPE_PACK_EXPANSION. */
10839 type = expanded_args;
10840 expanded_args = NULL_TREE;
10848 type = TREE_VEC_ELT (expanded_args, i);
10850 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10852 if (type == error_mark_node)
10853 return error_mark_node;
10854 if (VOID_TYPE_P (type))
10856 if (complain & tf_error)
10858 error ("invalid parameter type %qT", type);
10860 error ("in declaration %q+D", in_decl);
10862 return error_mark_node;
10865 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10866 top-level qualifiers as required. */
10867 type = cv_unqualified (type_decays_to (type));
10869 /* We do not substitute into default arguments here. The standard
10870 mandates that they be instantiated only when needed, which is
10871 done in build_over_call. */
10872 default_arg = TREE_PURPOSE (arg_types);
10874 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10876 /* We've instantiated a template before its default arguments
10877 have been parsed. This can happen for a nested template
10878 class, and is not an error unless we require the default
10879 argument in a call of this function. */
10880 remaining_arg_types =
10881 tree_cons (default_arg, type, remaining_arg_types);
10882 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10883 remaining_arg_types);
10886 remaining_arg_types =
10887 hash_tree_cons (default_arg, type, remaining_arg_types);
10890 return remaining_arg_types;
10893 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10894 *not* handle the exception-specification for FNTYPE, because the
10895 initial substitution of explicitly provided template parameters
10896 during argument deduction forbids substitution into the
10897 exception-specification:
10901 All references in the function type of the function template to the
10902 corresponding template parameters are replaced by the specified tem-
10903 plate argument values. If a substitution in a template parameter or
10904 in the function type of the function template results in an invalid
10905 type, type deduction fails. [Note: The equivalent substitution in
10906 exception specifications is done only when the function is instanti-
10907 ated, at which point a program is ill-formed if the substitution
10908 results in an invalid type.] */
10911 tsubst_function_type (tree t,
10913 tsubst_flags_t complain,
10920 /* The TYPE_CONTEXT is not used for function/method types. */
10921 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10923 /* Substitute the return type. */
10924 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10925 if (return_type == error_mark_node)
10926 return error_mark_node;
10927 /* The standard does not presently indicate that creation of a
10928 function type with an invalid return type is a deduction failure.
10929 However, that is clearly analogous to creating an array of "void"
10930 or a reference to a reference. This is core issue #486. */
10931 if (TREE_CODE (return_type) == ARRAY_TYPE
10932 || TREE_CODE (return_type) == FUNCTION_TYPE)
10934 if (complain & tf_error)
10936 if (TREE_CODE (return_type) == ARRAY_TYPE)
10937 error ("function returning an array");
10939 error ("function returning a function");
10941 return error_mark_node;
10944 /* Substitute the argument types. */
10945 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10946 complain, in_decl);
10947 if (arg_types == error_mark_node)
10948 return error_mark_node;
10950 /* Construct a new type node and return it. */
10951 if (TREE_CODE (t) == FUNCTION_TYPE)
10953 fntype = build_function_type (return_type, arg_types);
10954 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
10958 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10959 if (! MAYBE_CLASS_TYPE_P (r))
10963 Type deduction may fail for any of the following
10966 -- Attempting to create "pointer to member of T" when T
10967 is not a class type. */
10968 if (complain & tf_error)
10969 error ("creating pointer to member function of non-class type %qT",
10971 return error_mark_node;
10974 fntype = build_method_type_directly (r, return_type,
10975 TREE_CHAIN (arg_types));
10977 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
10982 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
10983 ARGS into that specification, and return the substituted
10984 specification. If there is no specification, return NULL_TREE. */
10987 tsubst_exception_specification (tree fntype,
10989 tsubst_flags_t complain,
10996 specs = TYPE_RAISES_EXCEPTIONS (fntype);
10997 new_specs = NULL_TREE;
10998 if (specs && TREE_PURPOSE (specs))
11000 /* A noexcept-specifier. */
11001 tree expr = TREE_PURPOSE (specs);
11002 if (expr == boolean_true_node || expr == boolean_false_node)
11006 /* Defer instantiation of noexcept-specifiers to avoid
11007 excessive instantiations (c++/49107). */
11008 new_specs = make_node (DEFERRED_NOEXCEPT);
11009 if (DEFERRED_NOEXCEPT_SPEC_P (specs))
11011 /* We already partially instantiated this member template,
11012 so combine the new args with the old. */
11013 DEFERRED_NOEXCEPT_PATTERN (new_specs)
11014 = DEFERRED_NOEXCEPT_PATTERN (expr);
11015 DEFERRED_NOEXCEPT_ARGS (new_specs)
11016 = add_to_template_args (DEFERRED_NOEXCEPT_ARGS (expr), args);
11020 DEFERRED_NOEXCEPT_PATTERN (new_specs) = expr;
11021 DEFERRED_NOEXCEPT_ARGS (new_specs) = args;
11025 new_specs = tsubst_copy_and_build
11026 (expr, args, complain, in_decl, /*function_p=*/false,
11027 /*integral_constant_expression_p=*/true);
11028 new_specs = build_noexcept_spec (new_specs, complain);
11032 if (! TREE_VALUE (specs))
11039 tree expanded_specs = NULL_TREE;
11041 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
11043 /* Expand the pack expansion type. */
11044 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
11048 if (expanded_specs == error_mark_node)
11049 return error_mark_node;
11050 else if (TREE_CODE (expanded_specs) == TREE_VEC)
11051 len = TREE_VEC_LENGTH (expanded_specs);
11054 /* We're substituting into a member template, so
11055 we got a TYPE_PACK_EXPANSION back. Add that
11056 expansion and move on. */
11057 gcc_assert (TREE_CODE (expanded_specs)
11058 == TYPE_PACK_EXPANSION);
11059 new_specs = add_exception_specifier (new_specs,
11062 specs = TREE_CHAIN (specs);
11067 for (i = 0; i < len; ++i)
11069 if (expanded_specs)
11070 spec = TREE_VEC_ELT (expanded_specs, i);
11072 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
11073 if (spec == error_mark_node)
11075 new_specs = add_exception_specifier (new_specs, spec,
11079 specs = TREE_CHAIN (specs);
11085 /* Take the tree structure T and replace template parameters used
11086 therein with the argument vector ARGS. IN_DECL is an associated
11087 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
11088 Issue error and warning messages under control of COMPLAIN. Note
11089 that we must be relatively non-tolerant of extensions here, in
11090 order to preserve conformance; if we allow substitutions that
11091 should not be allowed, we may allow argument deductions that should
11092 not succeed, and therefore report ambiguous overload situations
11093 where there are none. In theory, we could allow the substitution,
11094 but indicate that it should have failed, and allow our caller to
11095 make sure that the right thing happens, but we don't try to do this
11098 This function is used for dealing with types, decls and the like;
11099 for expressions, use tsubst_expr or tsubst_copy. */
11102 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11104 enum tree_code code;
11105 tree type, r = NULL_TREE;
11107 if (t == NULL_TREE || t == error_mark_node
11108 || t == integer_type_node
11109 || t == void_type_node
11110 || t == char_type_node
11111 || t == unknown_type_node
11112 || TREE_CODE (t) == NAMESPACE_DECL
11113 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
11117 return tsubst_decl (t, args, complain);
11119 if (args == NULL_TREE)
11122 code = TREE_CODE (t);
11124 if (code == IDENTIFIER_NODE)
11125 type = IDENTIFIER_TYPE_VALUE (t);
11127 type = TREE_TYPE (t);
11129 gcc_assert (type != unknown_type_node);
11131 /* Reuse typedefs. We need to do this to handle dependent attributes,
11132 such as attribute aligned. */
11134 && typedef_variant_p (t))
11136 tree decl = TYPE_NAME (t);
11138 if (TYPE_DECL_ALIAS_P (decl)
11139 && DECL_LANG_SPECIFIC (decl)
11140 && DECL_TEMPLATE_INFO (decl)
11141 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl)))
11143 /* DECL represents an alias template and we want to
11144 instantiate it. Let's substitute our arguments for the
11145 template parameters into the declaration and get the
11147 r = tsubst (decl, args, complain, decl);
11149 else if (DECL_CLASS_SCOPE_P (decl)
11150 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
11151 && uses_template_parms (DECL_CONTEXT (decl)))
11153 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11154 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
11155 r = retrieve_specialization (tmpl, gen_args, 0);
11157 else if (DECL_FUNCTION_SCOPE_P (decl)
11158 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
11159 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
11160 r = retrieve_local_specialization (decl);
11162 /* The typedef is from a non-template context. */
11168 r = cp_build_qualified_type_real
11169 (r, cp_type_quals (t) | cp_type_quals (r),
11170 complain | tf_ignore_bad_quals);
11173 /* Else we must be instantiating the typedef, so fall through. */
11177 && code != TYPENAME_TYPE
11178 && code != TEMPLATE_TYPE_PARM
11179 && code != IDENTIFIER_NODE
11180 && code != FUNCTION_TYPE
11181 && code != METHOD_TYPE)
11182 type = tsubst (type, args, complain, in_decl);
11183 if (type == error_mark_node)
11184 return error_mark_node;
11190 case ENUMERAL_TYPE:
11191 return tsubst_aggr_type (t, args, complain, in_decl,
11192 /*entering_scope=*/0);
11195 case IDENTIFIER_NODE:
11206 if (t == integer_type_node)
11209 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
11210 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
11214 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
11216 max = tsubst_expr (omax, args, complain, in_decl,
11217 /*integral_constant_expression_p=*/false);
11219 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
11221 if (TREE_CODE (max) == NOP_EXPR
11222 && TREE_SIDE_EFFECTS (omax)
11223 && !TREE_TYPE (max))
11224 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
11226 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
11227 with TREE_SIDE_EFFECTS that indicates this is not an integral
11228 constant expression. */
11229 if (processing_template_decl
11230 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
11232 gcc_assert (TREE_CODE (max) == NOP_EXPR);
11233 TREE_SIDE_EFFECTS (max) = 1;
11236 return compute_array_index_type (NULL_TREE, max, complain);
11239 case TEMPLATE_TYPE_PARM:
11240 case TEMPLATE_TEMPLATE_PARM:
11241 case BOUND_TEMPLATE_TEMPLATE_PARM:
11242 case TEMPLATE_PARM_INDEX:
11247 tree arg = NULL_TREE;
11251 gcc_assert (TREE_VEC_LENGTH (args) > 0);
11252 template_parm_level_and_index (t, &level, &idx);
11254 levels = TMPL_ARGS_DEPTH (args);
11255 if (level <= levels)
11257 arg = TMPL_ARG (args, level, idx);
11259 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
11260 /* See through ARGUMENT_PACK_SELECT arguments. */
11261 arg = ARGUMENT_PACK_SELECT_ARG (arg);
11264 if (arg == error_mark_node)
11265 return error_mark_node;
11266 else if (arg != NULL_TREE)
11268 if (ARGUMENT_PACK_P (arg))
11269 /* If ARG is an argument pack, we don't actually want to
11270 perform a substitution here, because substitutions
11271 for argument packs are only done
11272 element-by-element. We can get to this point when
11273 substituting the type of a non-type template
11274 parameter pack, when that type actually contains
11275 template parameter packs from an outer template, e.g.,
11277 template<typename... Types> struct A {
11278 template<Types... Values> struct B { };
11282 if (code == TEMPLATE_TYPE_PARM)
11285 gcc_assert (TYPE_P (arg));
11287 quals = cp_type_quals (arg) | cp_type_quals (t);
11289 return cp_build_qualified_type_real
11290 (arg, quals, complain | tf_ignore_bad_quals);
11292 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11294 /* We are processing a type constructed from a
11295 template template parameter. */
11296 tree argvec = tsubst (TYPE_TI_ARGS (t),
11297 args, complain, in_decl);
11298 if (argvec == error_mark_node)
11299 return error_mark_node;
11301 gcc_assert (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
11302 || TREE_CODE (arg) == TEMPLATE_DECL
11303 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
11305 if (TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE)
11306 /* Consider this code:
11308 template <template <class> class Template>
11310 template <class Arg> using Bind = Template<Arg>;
11313 template <template <class> class Template, class Arg>
11314 using Instantiate = Template<Arg>; //#0
11316 template <template <class> class Template,
11319 Instantiate<Internal<Template>::template Bind,
11322 When #1 is parsed, the
11323 BOUND_TEMPLATE_TEMPLATE_PARM representing the
11324 parameter `Template' in #0 matches the
11325 UNBOUND_CLASS_TEMPLATE representing the argument
11326 `Internal<Template>::template Bind'; We then want
11327 to assemble the type `Bind<Argument>' that can't
11328 be fully created right now, because
11329 `Internal<Template>' not being complete, the Bind
11330 template cannot be looked up in that context. So
11331 we need to "store" `Bind<Argument>' for later
11332 when the context of Bind becomes complete. Let's
11333 store that in a TYPENAME_TYPE. */
11334 return make_typename_type (TYPE_CONTEXT (arg),
11335 build_nt (TEMPLATE_ID_EXPR,
11336 TYPE_IDENTIFIER (arg),
11341 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
11342 are resolving nested-types in the signature of a
11343 member function templates. Otherwise ARG is a
11344 TEMPLATE_DECL and is the real template to be
11346 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11347 arg = TYPE_NAME (arg);
11349 r = lookup_template_class (arg,
11351 DECL_CONTEXT (arg),
11352 /*entering_scope=*/0,
11354 return cp_build_qualified_type_real
11355 (r, cp_type_quals (t), complain);
11358 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
11359 return convert_from_reference (unshare_expr (arg));
11363 /* This can happen during the attempted tsubst'ing in
11364 unify. This means that we don't yet have any information
11365 about the template parameter in question. */
11368 /* If we get here, we must have been looking at a parm for a
11369 more deeply nested template. Make a new version of this
11370 template parameter, but with a lower level. */
11373 case TEMPLATE_TYPE_PARM:
11374 case TEMPLATE_TEMPLATE_PARM:
11375 case BOUND_TEMPLATE_TEMPLATE_PARM:
11376 if (cp_type_quals (t))
11378 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
11379 r = cp_build_qualified_type_real
11380 (r, cp_type_quals (t),
11381 complain | (code == TEMPLATE_TYPE_PARM
11382 ? tf_ignore_bad_quals : 0));
11387 TEMPLATE_TYPE_PARM_INDEX (r)
11388 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
11389 r, levels, args, complain);
11390 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
11391 TYPE_MAIN_VARIANT (r) = r;
11392 TYPE_POINTER_TO (r) = NULL_TREE;
11393 TYPE_REFERENCE_TO (r) = NULL_TREE;
11395 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
11396 /* We have reduced the level of the template
11397 template parameter, but not the levels of its
11398 template parameters, so canonical_type_parameter
11399 will not be able to find the canonical template
11400 template parameter for this level. Thus, we
11401 require structural equality checking to compare
11402 TEMPLATE_TEMPLATE_PARMs. */
11403 SET_TYPE_STRUCTURAL_EQUALITY (r);
11404 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
11405 SET_TYPE_STRUCTURAL_EQUALITY (r);
11407 TYPE_CANONICAL (r) = canonical_type_parameter (r);
11409 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11411 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
11412 complain, in_decl);
11413 if (argvec == error_mark_node)
11414 return error_mark_node;
11416 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
11417 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
11422 case TEMPLATE_PARM_INDEX:
11423 r = reduce_template_parm_level (t, type, levels, args, complain);
11427 gcc_unreachable ();
11435 tree purpose, value, chain;
11437 if (t == void_list_node)
11440 purpose = TREE_PURPOSE (t);
11443 purpose = tsubst (purpose, args, complain, in_decl);
11444 if (purpose == error_mark_node)
11445 return error_mark_node;
11447 value = TREE_VALUE (t);
11450 value = tsubst (value, args, complain, in_decl);
11451 if (value == error_mark_node)
11452 return error_mark_node;
11454 chain = TREE_CHAIN (t);
11455 if (chain && chain != void_type_node)
11457 chain = tsubst (chain, args, complain, in_decl);
11458 if (chain == error_mark_node)
11459 return error_mark_node;
11461 if (purpose == TREE_PURPOSE (t)
11462 && value == TREE_VALUE (t)
11463 && chain == TREE_CHAIN (t))
11465 return hash_tree_cons (purpose, value, chain);
11469 /* We should never be tsubsting a binfo. */
11470 gcc_unreachable ();
11473 /* A vector of template arguments. */
11474 gcc_assert (!type);
11475 return tsubst_template_args (t, args, complain, in_decl);
11478 case REFERENCE_TYPE:
11480 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
11485 Type deduction may fail for any of the following
11488 -- Attempting to create a pointer to reference type.
11489 -- Attempting to create a reference to a reference type or
11490 a reference to void.
11492 Core issue 106 says that creating a reference to a reference
11493 during instantiation is no longer a cause for failure. We
11494 only enforce this check in strict C++98 mode. */
11495 if ((TREE_CODE (type) == REFERENCE_TYPE
11496 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
11497 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
11499 static location_t last_loc;
11501 /* We keep track of the last time we issued this error
11502 message to avoid spewing a ton of messages during a
11503 single bad template instantiation. */
11504 if (complain & tf_error
11505 && last_loc != input_location)
11507 if (TREE_CODE (type) == VOID_TYPE)
11508 error ("forming reference to void");
11509 else if (code == POINTER_TYPE)
11510 error ("forming pointer to reference type %qT", type);
11512 error ("forming reference to reference type %qT", type);
11513 last_loc = input_location;
11516 return error_mark_node;
11518 else if (code == POINTER_TYPE)
11520 r = build_pointer_type (type);
11521 if (TREE_CODE (type) == METHOD_TYPE)
11522 r = build_ptrmemfunc_type (r);
11524 else if (TREE_CODE (type) == REFERENCE_TYPE)
11525 /* In C++0x, during template argument substitution, when there is an
11526 attempt to create a reference to a reference type, reference
11527 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
11529 "If a template-argument for a template-parameter T names a type
11530 that is a reference to a type A, an attempt to create the type
11531 'lvalue reference to cv T' creates the type 'lvalue reference to
11532 A,' while an attempt to create the type type rvalue reference to
11533 cv T' creates the type T"
11535 r = cp_build_reference_type
11537 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
11539 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
11540 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
11542 if (r != error_mark_node)
11543 /* Will this ever be needed for TYPE_..._TO values? */
11550 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
11551 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
11555 Type deduction may fail for any of the following
11558 -- Attempting to create "pointer to member of T" when T
11559 is not a class type. */
11560 if (complain & tf_error)
11561 error ("creating pointer to member of non-class type %qT", r);
11562 return error_mark_node;
11564 if (TREE_CODE (type) == REFERENCE_TYPE)
11566 if (complain & tf_error)
11567 error ("creating pointer to member reference type %qT", type);
11568 return error_mark_node;
11570 if (TREE_CODE (type) == VOID_TYPE)
11572 if (complain & tf_error)
11573 error ("creating pointer to member of type void");
11574 return error_mark_node;
11576 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
11577 if (TREE_CODE (type) == FUNCTION_TYPE)
11579 /* The type of the implicit object parameter gets its
11580 cv-qualifiers from the FUNCTION_TYPE. */
11582 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
11583 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
11584 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
11588 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
11592 case FUNCTION_TYPE:
11597 fntype = tsubst_function_type (t, args, complain, in_decl);
11598 if (fntype == error_mark_node)
11599 return error_mark_node;
11601 /* Substitute the exception specification. */
11602 specs = tsubst_exception_specification (t, args, complain,
11603 in_decl, /*defer_ok*/true);
11604 if (specs == error_mark_node)
11605 return error_mark_node;
11607 fntype = build_exception_variant (fntype, specs);
11612 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
11613 if (domain == error_mark_node)
11614 return error_mark_node;
11616 /* As an optimization, we avoid regenerating the array type if
11617 it will obviously be the same as T. */
11618 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
11621 /* These checks should match the ones in grokdeclarator.
11625 The deduction may fail for any of the following reasons:
11627 -- Attempting to create an array with an element type that
11628 is void, a function type, or a reference type, or [DR337]
11629 an abstract class type. */
11630 if (TREE_CODE (type) == VOID_TYPE
11631 || TREE_CODE (type) == FUNCTION_TYPE
11632 || TREE_CODE (type) == REFERENCE_TYPE)
11634 if (complain & tf_error)
11635 error ("creating array of %qT", type);
11636 return error_mark_node;
11638 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
11640 if (complain & tf_error)
11641 error ("creating array of %qT, which is an abstract class type",
11643 return error_mark_node;
11646 r = build_cplus_array_type (type, domain);
11648 if (TYPE_USER_ALIGN (t))
11650 TYPE_ALIGN (r) = TYPE_ALIGN (t);
11651 TYPE_USER_ALIGN (r) = 1;
11657 case TYPENAME_TYPE:
11659 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11660 in_decl, /*entering_scope=*/1);
11661 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
11662 complain, in_decl);
11664 if (ctx == error_mark_node || f == error_mark_node)
11665 return error_mark_node;
11667 if (!MAYBE_CLASS_TYPE_P (ctx))
11669 if (complain & tf_error)
11670 error ("%qT is not a class, struct, or union type", ctx);
11671 return error_mark_node;
11673 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
11675 /* Normally, make_typename_type does not require that the CTX
11676 have complete type in order to allow things like:
11678 template <class T> struct S { typename S<T>::X Y; };
11680 But, such constructs have already been resolved by this
11681 point, so here CTX really should have complete type, unless
11682 it's a partial instantiation. */
11683 ctx = complete_type (ctx);
11684 if (!COMPLETE_TYPE_P (ctx))
11686 if (complain & tf_error)
11687 cxx_incomplete_type_error (NULL_TREE, ctx);
11688 return error_mark_node;
11692 f = make_typename_type (ctx, f, typename_type,
11693 (complain & tf_error) | tf_keep_type_decl);
11694 if (f == error_mark_node)
11696 if (TREE_CODE (f) == TYPE_DECL)
11698 complain |= tf_ignore_bad_quals;
11702 if (TREE_CODE (f) != TYPENAME_TYPE)
11704 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
11706 if (complain & tf_error)
11707 error ("%qT resolves to %qT, which is not an enumeration type",
11710 return error_mark_node;
11712 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
11714 if (complain & tf_error)
11715 error ("%qT resolves to %qT, which is is not a class type",
11718 return error_mark_node;
11722 return cp_build_qualified_type_real
11723 (f, cp_type_quals (f) | cp_type_quals (t), complain);
11726 case UNBOUND_CLASS_TEMPLATE:
11728 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11729 in_decl, /*entering_scope=*/1);
11730 tree name = TYPE_IDENTIFIER (t);
11731 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11733 if (ctx == error_mark_node || name == error_mark_node)
11734 return error_mark_node;
11737 parm_list = tsubst_template_parms (parm_list, args, complain);
11738 return make_unbound_class_template (ctx, name, parm_list, complain);
11745 ++cp_unevaluated_operand;
11746 ++c_inhibit_evaluation_warnings;
11748 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11750 /*integral_constant_expression_p=*/false);
11752 --cp_unevaluated_operand;
11753 --c_inhibit_evaluation_warnings;
11755 type = finish_typeof (type);
11756 return cp_build_qualified_type_real (type,
11758 | cp_type_quals (type),
11762 case DECLTYPE_TYPE:
11766 ++cp_unevaluated_operand;
11767 ++c_inhibit_evaluation_warnings;
11769 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11771 /*integral_constant_expression_p=*/false);
11773 --cp_unevaluated_operand;
11774 --c_inhibit_evaluation_warnings;
11776 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11777 type = lambda_capture_field_type (type);
11778 else if (DECLTYPE_FOR_LAMBDA_PROXY (t))
11779 type = lambda_proxy_type (type);
11781 type = finish_decltype_type
11782 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain);
11783 return cp_build_qualified_type_real (type,
11785 | cp_type_quals (type),
11789 case UNDERLYING_TYPE:
11791 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11792 complain, in_decl);
11793 return finish_underlying_type (type);
11796 case TYPE_ARGUMENT_PACK:
11797 case NONTYPE_ARGUMENT_PACK:
11799 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11801 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11805 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11807 /* For template nontype argument packs, also substitute into
11809 if (code == NONTYPE_ARGUMENT_PACK)
11810 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11828 /* We should use one of the expression tsubsts for these codes. */
11829 gcc_unreachable ();
11832 sorry ("use of %qs in template", tree_code_name [(int) code]);
11833 return error_mark_node;
11837 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11838 type of the expression on the left-hand side of the "." or "->"
11842 tsubst_baselink (tree baselink, tree object_type,
11843 tree args, tsubst_flags_t complain, tree in_decl)
11846 tree qualifying_scope;
11849 tree template_args = 0;
11850 bool template_id_p = false;
11852 /* A baselink indicates a function from a base class. Both the
11853 BASELINK_ACCESS_BINFO and the base class referenced may
11854 indicate bases of the template class, rather than the
11855 instantiated class. In addition, lookups that were not
11856 ambiguous before may be ambiguous now. Therefore, we perform
11857 the lookup again. */
11858 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11859 qualifying_scope = tsubst (qualifying_scope, args,
11860 complain, in_decl);
11861 fns = BASELINK_FUNCTIONS (baselink);
11862 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11863 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11865 template_id_p = true;
11866 template_args = TREE_OPERAND (fns, 1);
11867 fns = TREE_OPERAND (fns, 0);
11869 template_args = tsubst_template_args (template_args, args,
11870 complain, in_decl);
11872 name = DECL_NAME (get_first_fn (fns));
11873 if (IDENTIFIER_TYPENAME_P (name))
11874 name = mangle_conv_op_name_for_type (optype);
11875 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11877 return error_mark_node;
11879 /* If lookup found a single function, mark it as used at this
11880 point. (If it lookup found multiple functions the one selected
11881 later by overload resolution will be marked as used at that
11883 if (BASELINK_P (baselink))
11884 fns = BASELINK_FUNCTIONS (baselink);
11885 if (!template_id_p && !really_overloaded_fn (fns))
11886 mark_used (OVL_CURRENT (fns));
11888 /* Add back the template arguments, if present. */
11889 if (BASELINK_P (baselink) && template_id_p)
11890 BASELINK_FUNCTIONS (baselink)
11891 = build_nt (TEMPLATE_ID_EXPR,
11892 BASELINK_FUNCTIONS (baselink),
11894 /* Update the conversion operator type. */
11895 BASELINK_OPTYPE (baselink) = optype;
11898 object_type = current_class_type;
11899 return adjust_result_of_qualified_name_lookup (baselink,
11904 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11905 true if the qualified-id will be a postfix-expression in-and-of
11906 itself; false if more of the postfix-expression follows the
11907 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11911 tsubst_qualified_id (tree qualified_id, tree args,
11912 tsubst_flags_t complain, tree in_decl,
11913 bool done, bool address_p)
11919 tree template_args;
11921 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11923 /* Figure out what name to look up. */
11924 name = TREE_OPERAND (qualified_id, 1);
11925 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11927 is_template = true;
11928 template_args = TREE_OPERAND (name, 1);
11930 template_args = tsubst_template_args (template_args, args,
11931 complain, in_decl);
11932 name = TREE_OPERAND (name, 0);
11936 is_template = false;
11937 template_args = NULL_TREE;
11940 /* Substitute into the qualifying scope. When there are no ARGS, we
11941 are just trying to simplify a non-dependent expression. In that
11942 case the qualifying scope may be dependent, and, in any case,
11943 substituting will not help. */
11944 scope = TREE_OPERAND (qualified_id, 0);
11947 scope = tsubst (scope, args, complain, in_decl);
11948 expr = tsubst_copy (name, args, complain, in_decl);
11953 if (dependent_scope_p (scope))
11956 expr = build_min_nt (TEMPLATE_ID_EXPR, expr, template_args);
11957 return build_qualified_name (NULL_TREE, scope, expr,
11958 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
11961 if (!BASELINK_P (name) && !DECL_P (expr))
11963 if (TREE_CODE (expr) == BIT_NOT_EXPR)
11965 /* A BIT_NOT_EXPR is used to represent a destructor. */
11966 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
11968 error ("qualifying type %qT does not match destructor name ~%qT",
11969 scope, TREE_OPERAND (expr, 0));
11970 expr = error_mark_node;
11973 expr = lookup_qualified_name (scope, complete_dtor_identifier,
11974 /*is_type_p=*/0, false);
11977 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
11978 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
11979 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
11981 if (complain & tf_error)
11983 error ("dependent-name %qE is parsed as a non-type, but "
11984 "instantiation yields a type", qualified_id);
11985 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
11987 return error_mark_node;
11993 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
11995 /* Remember that there was a reference to this entity. */
11999 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
12001 if (complain & tf_error)
12002 qualified_name_lookup_error (scope,
12003 TREE_OPERAND (qualified_id, 1),
12004 expr, input_location);
12005 return error_mark_node;
12009 expr = lookup_template_function (expr, template_args);
12011 if (expr == error_mark_node && complain & tf_error)
12012 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
12013 expr, input_location);
12014 else if (TYPE_P (scope))
12016 expr = (adjust_result_of_qualified_name_lookup
12017 (expr, scope, current_class_type));
12018 expr = (finish_qualified_id_expr
12019 (scope, expr, done, address_p && PTRMEM_OK_P (qualified_id),
12020 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
12021 /*template_arg_p=*/false));
12024 /* Expressions do not generally have reference type. */
12025 if (TREE_CODE (expr) != SCOPE_REF
12026 /* However, if we're about to form a pointer-to-member, we just
12027 want the referenced member referenced. */
12028 && TREE_CODE (expr) != OFFSET_REF)
12029 expr = convert_from_reference (expr);
12034 /* Like tsubst, but deals with expressions. This function just replaces
12035 template parms; to finish processing the resultant expression, use
12036 tsubst_copy_and_build or tsubst_expr. */
12039 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
12041 enum tree_code code;
12044 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
12047 code = TREE_CODE (t);
12052 r = retrieve_local_specialization (t);
12058 /* We get here for a use of 'this' in an NSDMI. */
12059 if (DECL_NAME (t) == this_identifier
12060 && at_function_scope_p ()
12061 && DECL_CONSTRUCTOR_P (current_function_decl))
12062 return current_class_ptr;
12064 /* This can happen for a parameter name used later in a function
12065 declaration (such as in a late-specified return type). Just
12066 make a dummy decl, since it's only used for its type. */
12067 gcc_assert (cp_unevaluated_operand != 0);
12068 /* We copy T because want to tsubst the PARM_DECL only,
12069 not the following PARM_DECLs that are chained to T. */
12071 r = tsubst_decl (c, args, complain);
12072 /* Give it the template pattern as its context; its true context
12073 hasn't been instantiated yet and this is good enough for
12075 DECL_CONTEXT (r) = DECL_CONTEXT (t);
12078 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
12079 r = ARGUMENT_PACK_SELECT_ARG (r);
12088 if (DECL_TEMPLATE_PARM_P (t))
12089 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
12090 /* There is no need to substitute into namespace-scope
12092 if (DECL_NAMESPACE_SCOPE_P (t))
12094 /* If ARGS is NULL, then T is known to be non-dependent. */
12095 if (args == NULL_TREE)
12096 return integral_constant_value (t);
12098 /* Unfortunately, we cannot just call lookup_name here.
12101 template <int I> int f() {
12103 struct S { void g() { E e = a; } };
12106 When we instantiate f<7>::S::g(), say, lookup_name is not
12107 clever enough to find f<7>::a. */
12109 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
12110 /*entering_scope=*/0);
12112 for (v = TYPE_VALUES (enum_type);
12114 v = TREE_CHAIN (v))
12115 if (TREE_PURPOSE (v) == DECL_NAME (t))
12116 return TREE_VALUE (v);
12118 /* We didn't find the name. That should never happen; if
12119 name-lookup found it during preliminary parsing, we
12120 should find it again here during instantiation. */
12121 gcc_unreachable ();
12126 if (DECL_CONTEXT (t))
12130 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
12131 /*entering_scope=*/1);
12132 if (ctx != DECL_CONTEXT (t))
12134 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
12137 if (complain & tf_error)
12138 error ("using invalid field %qD", t);
12139 return error_mark_node;
12148 case FUNCTION_DECL:
12149 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
12150 || local_variable_p (t))
12151 t = tsubst (t, args, complain, in_decl);
12155 case NAMESPACE_DECL:
12159 /* An OVERLOAD will always be a non-dependent overload set; an
12160 overload set from function scope will just be represented with an
12161 IDENTIFIER_NODE, and from class scope with a BASELINK. */
12162 gcc_assert (!uses_template_parms (t));
12166 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
12168 case TEMPLATE_DECL:
12169 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
12170 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
12171 args, complain, in_decl);
12172 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
12173 return tsubst (t, args, complain, in_decl);
12174 else if (DECL_CLASS_SCOPE_P (t)
12175 && uses_template_parms (DECL_CONTEXT (t)))
12177 /* Template template argument like the following example need
12180 template <template <class> class TT> struct C {};
12181 template <class T> struct D {
12182 template <class U> struct E {};
12187 We are processing the template argument `E' in #1 for
12188 the template instantiation #2. Originally, `E' is a
12189 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
12190 have to substitute this with one having context `D<int>'. */
12192 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
12193 return lookup_field (context, DECL_NAME(t), 0, false);
12196 /* Ordinary template template argument. */
12200 case REINTERPRET_CAST_EXPR:
12201 case CONST_CAST_EXPR:
12202 case STATIC_CAST_EXPR:
12203 case DYNAMIC_CAST_EXPR:
12204 case IMPLICIT_CONV_EXPR:
12208 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12209 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12212 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12218 ++cp_unevaluated_operand;
12219 ++c_inhibit_evaluation_warnings;
12220 /* We only want to compute the number of arguments. */
12221 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
12222 complain, in_decl);
12223 --cp_unevaluated_operand;
12224 --c_inhibit_evaluation_warnings;
12226 if (TREE_CODE (expanded) == TREE_VEC)
12227 len = TREE_VEC_LENGTH (expanded);
12229 if (expanded == error_mark_node)
12230 return error_mark_node;
12231 else if (PACK_EXPANSION_P (expanded)
12232 || (TREE_CODE (expanded) == TREE_VEC
12234 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
12236 if (TREE_CODE (expanded) == TREE_VEC)
12237 expanded = TREE_VEC_ELT (expanded, len - 1);
12239 if (TYPE_P (expanded))
12240 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
12241 complain & tf_error);
12243 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
12244 complain & tf_error);
12247 return build_int_cst (size_type_node, len);
12253 case TRUTH_NOT_EXPR:
12256 case UNARY_PLUS_EXPR: /* Unary + */
12258 case AT_ENCODE_EXPR:
12262 case REALPART_EXPR:
12263 case IMAGPART_EXPR:
12265 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12266 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12268 case COMPONENT_REF:
12273 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
12274 name = TREE_OPERAND (t, 1);
12275 if (TREE_CODE (name) == BIT_NOT_EXPR)
12277 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12278 complain, in_decl);
12279 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12281 else if (TREE_CODE (name) == SCOPE_REF
12282 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
12284 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
12285 complain, in_decl);
12286 name = TREE_OPERAND (name, 1);
12287 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12288 complain, in_decl);
12289 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12290 name = build_qualified_name (/*type=*/NULL_TREE,
12292 /*template_p=*/false);
12294 else if (BASELINK_P (name))
12295 name = tsubst_baselink (name,
12296 non_reference (TREE_TYPE (object)),
12300 name = tsubst_copy (name, args, complain, in_decl);
12301 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
12307 case TRUNC_DIV_EXPR:
12308 case CEIL_DIV_EXPR:
12309 case FLOOR_DIV_EXPR:
12310 case ROUND_DIV_EXPR:
12311 case EXACT_DIV_EXPR:
12315 case TRUNC_MOD_EXPR:
12316 case FLOOR_MOD_EXPR:
12317 case TRUTH_ANDIF_EXPR:
12318 case TRUTH_ORIF_EXPR:
12319 case TRUTH_AND_EXPR:
12320 case TRUTH_OR_EXPR:
12333 case COMPOUND_EXPR:
12336 case PREDECREMENT_EXPR:
12337 case PREINCREMENT_EXPR:
12338 case POSTDECREMENT_EXPR:
12339 case POSTINCREMENT_EXPR:
12341 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12342 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12345 return build_qualified_name (/*type=*/NULL_TREE,
12346 tsubst_copy (TREE_OPERAND (t, 0),
12347 args, complain, in_decl),
12348 tsubst_copy (TREE_OPERAND (t, 1),
12349 args, complain, in_decl),
12350 QUALIFIED_NAME_IS_TEMPLATE (t));
12355 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12356 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12357 NULL_TREE, NULL_TREE);
12361 int n = VL_EXP_OPERAND_LENGTH (t);
12362 tree result = build_vl_exp (CALL_EXPR, n);
12364 for (i = 0; i < n; i++)
12365 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
12366 complain, in_decl);
12372 case PSEUDO_DTOR_EXPR:
12375 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12376 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12377 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12378 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12385 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12386 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12387 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12388 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
12395 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12396 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12397 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
12398 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
12402 case TEMPLATE_ID_EXPR:
12404 /* Substituted template arguments */
12405 tree fn = TREE_OPERAND (t, 0);
12406 tree targs = TREE_OPERAND (t, 1);
12408 fn = tsubst_copy (fn, args, complain, in_decl);
12410 targs = tsubst_template_args (targs, args, complain, in_decl);
12412 return lookup_template_function (fn, targs);
12417 tree purpose, value, chain;
12419 if (t == void_list_node)
12422 purpose = TREE_PURPOSE (t);
12424 purpose = tsubst_copy (purpose, args, complain, in_decl);
12425 value = TREE_VALUE (t);
12427 value = tsubst_copy (value, args, complain, in_decl);
12428 chain = TREE_CHAIN (t);
12429 if (chain && chain != void_type_node)
12430 chain = tsubst_copy (chain, args, complain, in_decl);
12431 if (purpose == TREE_PURPOSE (t)
12432 && value == TREE_VALUE (t)
12433 && chain == TREE_CHAIN (t))
12435 return tree_cons (purpose, value, chain);
12440 case ENUMERAL_TYPE:
12442 case TEMPLATE_TYPE_PARM:
12443 case TEMPLATE_TEMPLATE_PARM:
12444 case BOUND_TEMPLATE_TEMPLATE_PARM:
12445 case TEMPLATE_PARM_INDEX:
12447 case REFERENCE_TYPE:
12449 case FUNCTION_TYPE:
12452 case TYPENAME_TYPE:
12453 case UNBOUND_CLASS_TEMPLATE:
12455 case DECLTYPE_TYPE:
12457 return tsubst (t, args, complain, in_decl);
12459 case IDENTIFIER_NODE:
12460 if (IDENTIFIER_TYPENAME_P (t))
12462 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12463 return mangle_conv_op_name_for_type (new_type);
12469 /* This is handled by tsubst_copy_and_build. */
12470 gcc_unreachable ();
12473 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
12475 tsubst (TREE_TYPE (t), args, complain, in_decl));
12477 case CLEANUP_POINT_EXPR:
12478 /* We shouldn't have built any of these during initial template
12479 generation. Instead, they should be built during instantiation
12480 in response to the saved STMT_IS_FULL_EXPR_P setting. */
12481 gcc_unreachable ();
12485 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12486 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12487 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12488 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
12489 mark_used (TREE_OPERAND (r, 1));
12492 case EXPR_PACK_EXPANSION:
12493 error ("invalid use of pack expansion expression");
12494 return error_mark_node;
12496 case NONTYPE_ARGUMENT_PACK:
12497 error ("use %<...%> to expand argument pack");
12498 return error_mark_node;
12505 /* Instantiate any typedefs in the type. */
12506 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12507 r = fold_convert (type, t);
12508 gcc_assert (TREE_CODE (r) == code);
12513 /* These can sometimes show up in a partial instantiation, but never
12514 involve template parms. */
12515 gcc_assert (!uses_template_parms (t));
12519 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
12520 gcc_checking_assert (false);
12525 /* Like tsubst_copy, but specifically for OpenMP clauses. */
12528 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
12531 tree new_clauses = NULL, nc, oc;
12533 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
12535 nc = copy_node (oc);
12536 OMP_CLAUSE_CHAIN (nc) = new_clauses;
12539 switch (OMP_CLAUSE_CODE (nc))
12541 case OMP_CLAUSE_LASTPRIVATE:
12542 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
12544 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
12545 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
12546 in_decl, /*integral_constant_expression_p=*/false);
12547 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
12548 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
12551 case OMP_CLAUSE_PRIVATE:
12552 case OMP_CLAUSE_SHARED:
12553 case OMP_CLAUSE_FIRSTPRIVATE:
12554 case OMP_CLAUSE_REDUCTION:
12555 case OMP_CLAUSE_COPYIN:
12556 case OMP_CLAUSE_COPYPRIVATE:
12557 case OMP_CLAUSE_IF:
12558 case OMP_CLAUSE_NUM_THREADS:
12559 case OMP_CLAUSE_SCHEDULE:
12560 case OMP_CLAUSE_COLLAPSE:
12561 case OMP_CLAUSE_FINAL:
12562 OMP_CLAUSE_OPERAND (nc, 0)
12563 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
12564 in_decl, /*integral_constant_expression_p=*/false);
12566 case OMP_CLAUSE_NOWAIT:
12567 case OMP_CLAUSE_ORDERED:
12568 case OMP_CLAUSE_DEFAULT:
12569 case OMP_CLAUSE_UNTIED:
12570 case OMP_CLAUSE_MERGEABLE:
12573 gcc_unreachable ();
12577 return finish_omp_clauses (nreverse (new_clauses));
12580 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
12583 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
12586 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
12588 tree purpose, value, chain;
12593 if (TREE_CODE (t) != TREE_LIST)
12594 return tsubst_copy_and_build (t, args, complain, in_decl,
12595 /*function_p=*/false,
12596 /*integral_constant_expression_p=*/false);
12598 if (t == void_list_node)
12601 purpose = TREE_PURPOSE (t);
12603 purpose = RECUR (purpose);
12604 value = TREE_VALUE (t);
12605 if (value && TREE_CODE (value) != LABEL_DECL)
12606 value = RECUR (value);
12607 chain = TREE_CHAIN (t);
12608 if (chain && chain != void_type_node)
12609 chain = RECUR (chain);
12610 return tree_cons (purpose, value, chain);
12614 /* Substitute one OMP_FOR iterator. */
12617 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
12618 tree condv, tree incrv, tree *clauses,
12619 tree args, tsubst_flags_t complain, tree in_decl,
12620 bool integral_constant_expression_p)
12622 #define RECUR(NODE) \
12623 tsubst_expr ((NODE), args, complain, in_decl, \
12624 integral_constant_expression_p)
12625 tree decl, init, cond, incr, auto_node;
12627 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
12628 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
12629 decl = RECUR (TREE_OPERAND (init, 0));
12630 init = TREE_OPERAND (init, 1);
12631 auto_node = type_uses_auto (TREE_TYPE (decl));
12632 if (auto_node && init)
12634 tree init_expr = init;
12635 if (TREE_CODE (init_expr) == DECL_EXPR)
12636 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
12637 init_expr = RECUR (init_expr);
12639 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
12641 gcc_assert (!type_dependent_expression_p (decl));
12643 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
12645 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
12646 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12647 if (TREE_CODE (incr) == MODIFY_EXPR)
12648 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
12649 RECUR (TREE_OPERAND (incr, 1)),
12652 incr = RECUR (incr);
12653 TREE_VEC_ELT (declv, i) = decl;
12654 TREE_VEC_ELT (initv, i) = init;
12655 TREE_VEC_ELT (condv, i) = cond;
12656 TREE_VEC_ELT (incrv, i) = incr;
12660 if (init && TREE_CODE (init) != DECL_EXPR)
12663 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
12665 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
12666 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
12667 && OMP_CLAUSE_DECL (c) == decl)
12669 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
12670 && OMP_CLAUSE_DECL (c) == decl)
12671 error ("iteration variable %qD should not be firstprivate", decl);
12672 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
12673 && OMP_CLAUSE_DECL (c) == decl)
12674 error ("iteration variable %qD should not be reduction", decl);
12678 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
12679 OMP_CLAUSE_DECL (c) = decl;
12680 c = finish_omp_clauses (c);
12683 OMP_CLAUSE_CHAIN (c) = *clauses;
12688 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
12689 if (COMPARISON_CLASS_P (cond))
12690 cond = build2 (TREE_CODE (cond), boolean_type_node,
12691 RECUR (TREE_OPERAND (cond, 0)),
12692 RECUR (TREE_OPERAND (cond, 1)));
12694 cond = RECUR (cond);
12695 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12696 switch (TREE_CODE (incr))
12698 case PREINCREMENT_EXPR:
12699 case PREDECREMENT_EXPR:
12700 case POSTINCREMENT_EXPR:
12701 case POSTDECREMENT_EXPR:
12702 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
12703 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
12706 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12707 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12709 tree rhs = TREE_OPERAND (incr, 1);
12710 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12711 RECUR (TREE_OPERAND (incr, 0)),
12712 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12713 RECUR (TREE_OPERAND (rhs, 0)),
12714 RECUR (TREE_OPERAND (rhs, 1))));
12717 incr = RECUR (incr);
12720 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12721 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12723 tree lhs = RECUR (TREE_OPERAND (incr, 0));
12724 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
12725 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
12726 TREE_TYPE (decl), lhs,
12727 RECUR (TREE_OPERAND (incr, 2))));
12729 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
12730 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
12731 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
12733 tree rhs = TREE_OPERAND (incr, 2);
12734 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12735 RECUR (TREE_OPERAND (incr, 0)),
12736 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12737 RECUR (TREE_OPERAND (rhs, 0)),
12738 RECUR (TREE_OPERAND (rhs, 1))));
12741 incr = RECUR (incr);
12744 incr = RECUR (incr);
12748 TREE_VEC_ELT (declv, i) = decl;
12749 TREE_VEC_ELT (initv, i) = init;
12750 TREE_VEC_ELT (condv, i) = cond;
12751 TREE_VEC_ELT (incrv, i) = incr;
12755 /* Like tsubst_copy for expressions, etc. but also does semantic
12759 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12760 bool integral_constant_expression_p)
12762 #define RECUR(NODE) \
12763 tsubst_expr ((NODE), args, complain, in_decl, \
12764 integral_constant_expression_p)
12768 if (t == NULL_TREE || t == error_mark_node)
12771 if (EXPR_HAS_LOCATION (t))
12772 input_location = EXPR_LOCATION (t);
12773 if (STATEMENT_CODE_P (TREE_CODE (t)))
12774 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12776 switch (TREE_CODE (t))
12778 case STATEMENT_LIST:
12780 tree_stmt_iterator i;
12781 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12782 RECUR (tsi_stmt (i));
12786 case CTOR_INITIALIZER:
12787 finish_mem_initializers (tsubst_initializer_list
12788 (TREE_OPERAND (t, 0), args));
12792 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12796 tmp = RECUR (EXPR_STMT_EXPR (t));
12797 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12798 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12800 finish_expr_stmt (tmp);
12804 do_using_directive (USING_STMT_NAMESPACE (t));
12809 tree decl, pattern_decl;
12812 pattern_decl = decl = DECL_EXPR_DECL (t);
12813 if (TREE_CODE (decl) == LABEL_DECL)
12814 finish_label_decl (DECL_NAME (decl));
12815 else if (TREE_CODE (decl) == USING_DECL)
12817 tree scope = USING_DECL_SCOPE (decl);
12818 tree name = DECL_NAME (decl);
12821 scope = tsubst (scope, args, complain, in_decl);
12822 decl = lookup_qualified_name (scope, name,
12823 /*is_type_p=*/false,
12824 /*complain=*/false);
12825 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12826 qualified_name_lookup_error (scope, name, decl, input_location);
12828 do_local_using_decl (decl, scope, name);
12832 init = DECL_INITIAL (decl);
12833 decl = tsubst (decl, args, complain, in_decl);
12834 if (decl != error_mark_node)
12836 /* By marking the declaration as instantiated, we avoid
12837 trying to instantiate it. Since instantiate_decl can't
12838 handle local variables, and since we've already done
12839 all that needs to be done, that's the right thing to
12841 if (TREE_CODE (decl) == VAR_DECL)
12842 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12843 if (TREE_CODE (decl) == VAR_DECL
12844 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12845 /* Anonymous aggregates are a special case. */
12846 finish_anon_union (decl);
12847 else if (is_capture_proxy (DECL_EXPR_DECL (t)))
12849 DECL_CONTEXT (decl) = current_function_decl;
12850 insert_capture_proxy (decl);
12854 int const_init = false;
12855 maybe_push_decl (decl);
12856 if (TREE_CODE (decl) == VAR_DECL
12857 && DECL_PRETTY_FUNCTION_P (decl))
12859 /* For __PRETTY_FUNCTION__ we have to adjust the
12861 const char *const name
12862 = cxx_printable_name (current_function_decl, 2);
12863 init = cp_fname_init (name, &TREE_TYPE (decl));
12867 tree t = RECUR (init);
12871 /* If we had an initializer but it
12872 instantiated to nothing,
12873 value-initialize the object. This will
12874 only occur when the initializer was a
12875 pack expansion where the parameter packs
12876 used in that expansion were of length
12878 init = build_value_init (TREE_TYPE (decl),
12880 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12881 init = get_target_expr_sfinae (init, complain);
12887 if (TREE_CODE (decl) == VAR_DECL)
12888 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12890 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12895 /* A DECL_EXPR can also be used as an expression, in the condition
12896 clause of an if/for/while construct. */
12901 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12902 RECUR (FOR_INIT_STMT (t));
12903 finish_for_init_stmt (stmt);
12904 tmp = RECUR (FOR_COND (t));
12905 finish_for_cond (tmp, stmt);
12906 tmp = RECUR (FOR_EXPR (t));
12907 finish_for_expr (tmp, stmt);
12908 RECUR (FOR_BODY (t));
12909 finish_for_stmt (stmt);
12912 case RANGE_FOR_STMT:
12915 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12916 decl = RANGE_FOR_DECL (t);
12917 decl = tsubst (decl, args, complain, in_decl);
12918 maybe_push_decl (decl);
12919 expr = RECUR (RANGE_FOR_EXPR (t));
12920 stmt = cp_convert_range_for (stmt, decl, expr);
12921 RECUR (RANGE_FOR_BODY (t));
12922 finish_for_stmt (stmt);
12927 stmt = begin_while_stmt ();
12928 tmp = RECUR (WHILE_COND (t));
12929 finish_while_stmt_cond (tmp, stmt);
12930 RECUR (WHILE_BODY (t));
12931 finish_while_stmt (stmt);
12935 stmt = begin_do_stmt ();
12936 RECUR (DO_BODY (t));
12937 finish_do_body (stmt);
12938 tmp = RECUR (DO_COND (t));
12939 finish_do_stmt (tmp, stmt);
12943 stmt = begin_if_stmt ();
12944 tmp = RECUR (IF_COND (t));
12945 finish_if_stmt_cond (tmp, stmt);
12946 RECUR (THEN_CLAUSE (t));
12947 finish_then_clause (stmt);
12949 if (ELSE_CLAUSE (t))
12951 begin_else_clause (stmt);
12952 RECUR (ELSE_CLAUSE (t));
12953 finish_else_clause (stmt);
12956 finish_if_stmt (stmt);
12960 if (BIND_EXPR_BODY_BLOCK (t))
12961 stmt = begin_function_body ();
12963 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
12964 ? BCS_TRY_BLOCK : 0);
12966 RECUR (BIND_EXPR_BODY (t));
12968 if (BIND_EXPR_BODY_BLOCK (t))
12969 finish_function_body (stmt);
12971 finish_compound_stmt (stmt);
12975 finish_break_stmt ();
12978 case CONTINUE_STMT:
12979 finish_continue_stmt ();
12983 stmt = begin_switch_stmt ();
12984 tmp = RECUR (SWITCH_STMT_COND (t));
12985 finish_switch_cond (tmp, stmt);
12986 RECUR (SWITCH_STMT_BODY (t));
12987 finish_switch_stmt (stmt);
12990 case CASE_LABEL_EXPR:
12991 finish_case_label (EXPR_LOCATION (t),
12992 RECUR (CASE_LOW (t)),
12993 RECUR (CASE_HIGH (t)));
12998 tree decl = LABEL_EXPR_LABEL (t);
13001 label = finish_label_stmt (DECL_NAME (decl));
13002 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
13003 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
13008 tmp = GOTO_DESTINATION (t);
13009 if (TREE_CODE (tmp) != LABEL_DECL)
13010 /* Computed goto's must be tsubst'd into. On the other hand,
13011 non-computed gotos must not be; the identifier in question
13012 will have no binding. */
13015 tmp = DECL_NAME (tmp);
13016 finish_goto_stmt (tmp);
13020 tmp = finish_asm_stmt
13021 (ASM_VOLATILE_P (t),
13022 RECUR (ASM_STRING (t)),
13023 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
13024 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
13025 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
13026 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
13028 tree asm_expr = tmp;
13029 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
13030 asm_expr = TREE_OPERAND (asm_expr, 0);
13031 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
13038 stmt = begin_try_block ();
13039 RECUR (TRY_STMTS (t));
13040 finish_cleanup_try_block (stmt);
13041 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
13045 tree compound_stmt = NULL_TREE;
13047 if (FN_TRY_BLOCK_P (t))
13048 stmt = begin_function_try_block (&compound_stmt);
13050 stmt = begin_try_block ();
13052 RECUR (TRY_STMTS (t));
13054 if (FN_TRY_BLOCK_P (t))
13055 finish_function_try_block (stmt);
13057 finish_try_block (stmt);
13059 RECUR (TRY_HANDLERS (t));
13060 if (FN_TRY_BLOCK_P (t))
13061 finish_function_handler_sequence (stmt, compound_stmt);
13063 finish_handler_sequence (stmt);
13069 tree decl = HANDLER_PARMS (t);
13073 decl = tsubst (decl, args, complain, in_decl);
13074 /* Prevent instantiate_decl from trying to instantiate
13075 this variable. We've already done all that needs to be
13077 if (decl != error_mark_node)
13078 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
13080 stmt = begin_handler ();
13081 finish_handler_parms (decl, stmt);
13082 RECUR (HANDLER_BODY (t));
13083 finish_handler (stmt);
13088 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13091 case STATIC_ASSERT:
13094 tsubst_expr (STATIC_ASSERT_CONDITION (t),
13097 /*integral_constant_expression_p=*/true);
13098 finish_static_assert (condition,
13099 STATIC_ASSERT_MESSAGE (t),
13100 STATIC_ASSERT_SOURCE_LOCATION (t),
13101 /*member_p=*/false);
13106 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
13107 args, complain, in_decl);
13108 stmt = begin_omp_parallel ();
13109 RECUR (OMP_PARALLEL_BODY (t));
13110 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
13111 = OMP_PARALLEL_COMBINED (t);
13115 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
13116 args, complain, in_decl);
13117 stmt = begin_omp_task ();
13118 RECUR (OMP_TASK_BODY (t));
13119 finish_omp_task (tmp, stmt);
13124 tree clauses, body, pre_body;
13125 tree declv, initv, condv, incrv;
13128 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
13129 args, complain, in_decl);
13130 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13131 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13132 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13133 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13135 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
13136 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
13137 &clauses, args, complain, in_decl,
13138 integral_constant_expression_p);
13140 stmt = begin_omp_structured_block ();
13142 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
13143 if (TREE_VEC_ELT (initv, i) == NULL
13144 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
13145 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
13146 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
13148 tree init = RECUR (TREE_VEC_ELT (initv, i));
13149 gcc_assert (init == TREE_VEC_ELT (declv, i));
13150 TREE_VEC_ELT (initv, i) = NULL_TREE;
13154 tree decl_expr = TREE_VEC_ELT (initv, i);
13155 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
13156 gcc_assert (init != NULL);
13157 TREE_VEC_ELT (initv, i) = RECUR (init);
13158 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
13160 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
13163 pre_body = push_stmt_list ();
13164 RECUR (OMP_FOR_PRE_BODY (t));
13165 pre_body = pop_stmt_list (pre_body);
13167 body = push_stmt_list ();
13168 RECUR (OMP_FOR_BODY (t));
13169 body = pop_stmt_list (body);
13171 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
13172 body, pre_body, clauses);
13174 add_stmt (finish_omp_structured_block (stmt));
13180 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
13181 stmt = push_stmt_list ();
13182 RECUR (OMP_BODY (t));
13183 stmt = pop_stmt_list (stmt);
13186 OMP_BODY (t) = stmt;
13187 OMP_CLAUSES (t) = tmp;
13195 stmt = push_stmt_list ();
13196 RECUR (OMP_BODY (t));
13197 stmt = pop_stmt_list (stmt);
13200 OMP_BODY (t) = stmt;
13205 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
13206 if (TREE_CODE (TREE_OPERAND (t, 1)) != MODIFY_EXPR)
13208 tree op1 = TREE_OPERAND (t, 1);
13209 tree rhs1 = NULL_TREE;
13211 if (TREE_CODE (op1) == COMPOUND_EXPR)
13213 rhs1 = RECUR (TREE_OPERAND (op1, 0));
13214 op1 = TREE_OPERAND (op1, 1);
13216 lhs = RECUR (TREE_OPERAND (op1, 0));
13217 rhs = RECUR (TREE_OPERAND (op1, 1));
13218 finish_omp_atomic (OMP_ATOMIC, TREE_CODE (op1), lhs, rhs,
13219 NULL_TREE, NULL_TREE, rhs1);
13223 tree op1 = TREE_OPERAND (t, 1);
13224 tree v = NULL_TREE, lhs, rhs = NULL_TREE, lhs1 = NULL_TREE;
13225 tree rhs1 = NULL_TREE;
13226 enum tree_code code = TREE_CODE (TREE_OPERAND (op1, 1));
13227 enum tree_code opcode = NOP_EXPR;
13228 if (code == OMP_ATOMIC_READ)
13230 v = RECUR (TREE_OPERAND (op1, 0));
13231 lhs = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13233 else if (code == OMP_ATOMIC_CAPTURE_OLD
13234 || code == OMP_ATOMIC_CAPTURE_NEW)
13236 tree op11 = TREE_OPERAND (TREE_OPERAND (op1, 1), 1);
13237 v = RECUR (TREE_OPERAND (op1, 0));
13238 lhs1 = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13239 if (TREE_CODE (op11) == COMPOUND_EXPR)
13241 rhs1 = RECUR (TREE_OPERAND (op11, 0));
13242 op11 = TREE_OPERAND (op11, 1);
13244 lhs = RECUR (TREE_OPERAND (op11, 0));
13245 rhs = RECUR (TREE_OPERAND (op11, 1));
13246 opcode = TREE_CODE (op11);
13251 lhs = RECUR (TREE_OPERAND (op1, 0));
13252 rhs = RECUR (TREE_OPERAND (op1, 1));
13254 finish_omp_atomic (code, opcode, lhs, rhs, v, lhs1, rhs1);
13258 case TRANSACTION_EXPR:
13261 flags |= (TRANSACTION_EXPR_OUTER (t) ? TM_STMT_ATTR_OUTER : 0);
13262 flags |= (TRANSACTION_EXPR_RELAXED (t) ? TM_STMT_ATTR_RELAXED : 0);
13264 if (TRANSACTION_EXPR_IS_STMT (t))
13266 tree body = TRANSACTION_EXPR_BODY (t);
13267 tree noex = NULL_TREE;
13268 if (TREE_CODE (body) == MUST_NOT_THROW_EXPR)
13270 noex = MUST_NOT_THROW_COND (body);
13271 if (noex == NULL_TREE)
13272 noex = boolean_true_node;
13273 body = TREE_OPERAND (body, 0);
13275 stmt = begin_transaction_stmt (input_location, NULL, flags);
13277 finish_transaction_stmt (stmt, NULL, flags, RECUR (noex));
13281 stmt = build_transaction_expr (EXPR_LOCATION (t),
13282 RECUR (TRANSACTION_EXPR_BODY (t)),
13289 case MUST_NOT_THROW_EXPR:
13290 return build_must_not_throw_expr (RECUR (TREE_OPERAND (t, 0)),
13291 RECUR (MUST_NOT_THROW_COND (t)));
13293 case EXPR_PACK_EXPANSION:
13294 error ("invalid use of pack expansion expression");
13295 return error_mark_node;
13297 case NONTYPE_ARGUMENT_PACK:
13298 error ("use %<...%> to expand argument pack");
13299 return error_mark_node;
13302 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
13304 return tsubst_copy_and_build (t, args, complain, in_decl,
13305 /*function_p=*/false,
13306 integral_constant_expression_p);
13313 /* T is a postfix-expression that is not being used in a function
13314 call. Return the substituted version of T. */
13317 tsubst_non_call_postfix_expression (tree t, tree args,
13318 tsubst_flags_t complain,
13321 if (TREE_CODE (t) == SCOPE_REF)
13322 t = tsubst_qualified_id (t, args, complain, in_decl,
13323 /*done=*/false, /*address_p=*/false);
13325 t = tsubst_copy_and_build (t, args, complain, in_decl,
13326 /*function_p=*/false,
13327 /*integral_constant_expression_p=*/false);
13332 /* Like tsubst but deals with expressions and performs semantic
13333 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
13336 tsubst_copy_and_build (tree t,
13338 tsubst_flags_t complain,
13341 bool integral_constant_expression_p)
13343 #define RECUR(NODE) \
13344 tsubst_copy_and_build (NODE, args, complain, in_decl, \
13345 /*function_p=*/false, \
13346 integral_constant_expression_p)
13350 if (t == NULL_TREE || t == error_mark_node)
13353 switch (TREE_CODE (t))
13357 /* Fall through. */
13358 case IDENTIFIER_NODE:
13362 bool non_integral_constant_expression_p;
13363 const char *error_msg;
13365 if (IDENTIFIER_TYPENAME_P (t))
13367 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13368 t = mangle_conv_op_name_for_type (new_type);
13371 /* Look up the name. */
13372 decl = lookup_name (t);
13374 /* By convention, expressions use ERROR_MARK_NODE to indicate
13375 failure, not NULL_TREE. */
13376 if (decl == NULL_TREE)
13377 decl = error_mark_node;
13379 decl = finish_id_expression (t, decl, NULL_TREE,
13381 integral_constant_expression_p,
13382 /*allow_non_integral_constant_expression_p=*/(cxx_dialect >= cxx0x),
13383 &non_integral_constant_expression_p,
13384 /*template_p=*/false,
13386 /*address_p=*/false,
13387 /*template_arg_p=*/false,
13392 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
13394 if (complain & tf_error)
13395 unqualified_name_lookup_error (decl);
13396 decl = error_mark_node;
13401 case TEMPLATE_ID_EXPR:
13404 tree templ = RECUR (TREE_OPERAND (t, 0));
13405 tree targs = TREE_OPERAND (t, 1);
13408 targs = tsubst_template_args (targs, args, complain, in_decl);
13410 if (TREE_CODE (templ) == COMPONENT_REF)
13412 object = TREE_OPERAND (templ, 0);
13413 templ = TREE_OPERAND (templ, 1);
13416 object = NULL_TREE;
13417 templ = lookup_template_function (templ, targs);
13420 return build3 (COMPONENT_REF, TREE_TYPE (templ),
13421 object, templ, NULL_TREE);
13423 return baselink_for_fns (templ);
13428 tree r = RECUR (TREE_OPERAND (t, 0));
13430 if (REFERENCE_REF_P (t))
13432 /* A type conversion to reference type will be enclosed in
13433 such an indirect ref, but the substitution of the cast
13434 will have also added such an indirect ref. */
13435 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
13436 r = convert_from_reference (r);
13439 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
13445 (tsubst (TREE_TYPE (t), args, complain, in_decl),
13446 RECUR (TREE_OPERAND (t, 0)));
13448 case IMPLICIT_CONV_EXPR:
13450 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13451 tree expr = RECUR (TREE_OPERAND (t, 0));
13452 int flags = LOOKUP_IMPLICIT;
13453 if (IMPLICIT_CONV_EXPR_DIRECT_INIT (t))
13454 flags = LOOKUP_NORMAL;
13455 return perform_implicit_conversion_flags (type, expr, complain,
13462 tsubst (TREE_TYPE (t), args, complain, in_decl),
13463 RECUR (TREE_OPERAND (t, 0)));
13466 case REINTERPRET_CAST_EXPR:
13467 case CONST_CAST_EXPR:
13468 case DYNAMIC_CAST_EXPR:
13469 case STATIC_CAST_EXPR:
13474 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13475 if (integral_constant_expression_p
13476 && !cast_valid_in_integral_constant_expression_p (type))
13478 if (complain & tf_error)
13479 error ("a cast to a type other than an integral or "
13480 "enumeration type cannot appear in a constant-expression");
13481 return error_mark_node;
13484 op = RECUR (TREE_OPERAND (t, 0));
13486 switch (TREE_CODE (t))
13489 return build_functional_cast (type, op, complain);
13490 case REINTERPRET_CAST_EXPR:
13491 return build_reinterpret_cast (type, op, complain);
13492 case CONST_CAST_EXPR:
13493 return build_const_cast (type, op, complain);
13494 case DYNAMIC_CAST_EXPR:
13495 return build_dynamic_cast (type, op, complain);
13496 case STATIC_CAST_EXPR:
13497 return build_static_cast (type, op, complain);
13499 gcc_unreachable ();
13503 case POSTDECREMENT_EXPR:
13504 case POSTINCREMENT_EXPR:
13505 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13506 args, complain, in_decl);
13507 return build_x_unary_op (TREE_CODE (t), op1, complain);
13509 case PREDECREMENT_EXPR:
13510 case PREINCREMENT_EXPR:
13514 case TRUTH_NOT_EXPR:
13515 case UNARY_PLUS_EXPR: /* Unary + */
13516 case REALPART_EXPR:
13517 case IMAGPART_EXPR:
13518 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
13521 case FIX_TRUNC_EXPR:
13522 return cp_build_unary_op (FIX_TRUNC_EXPR, RECUR (TREE_OPERAND (t, 0)),
13526 op1 = TREE_OPERAND (t, 0);
13527 if (TREE_CODE (op1) == LABEL_DECL)
13528 return finish_label_address_expr (DECL_NAME (op1),
13529 EXPR_LOCATION (op1));
13530 if (TREE_CODE (op1) == SCOPE_REF)
13531 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
13532 /*done=*/true, /*address_p=*/true);
13534 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
13536 return build_x_unary_op (ADDR_EXPR, op1, complain);
13541 case TRUNC_DIV_EXPR:
13542 case CEIL_DIV_EXPR:
13543 case FLOOR_DIV_EXPR:
13544 case ROUND_DIV_EXPR:
13545 case EXACT_DIV_EXPR:
13549 case TRUNC_MOD_EXPR:
13550 case FLOOR_MOD_EXPR:
13551 case TRUTH_ANDIF_EXPR:
13552 case TRUTH_ORIF_EXPR:
13553 case TRUTH_AND_EXPR:
13554 case TRUTH_OR_EXPR:
13570 tree r = build_x_binary_op
13572 RECUR (TREE_OPERAND (t, 0)),
13573 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
13575 : TREE_CODE (TREE_OPERAND (t, 0))),
13576 RECUR (TREE_OPERAND (t, 1)),
13577 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
13579 : TREE_CODE (TREE_OPERAND (t, 1))),
13582 if (EXPR_P (r) && TREE_NO_WARNING (t))
13583 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13588 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
13589 /*address_p=*/false);
13591 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13592 args, complain, in_decl);
13593 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
13596 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
13597 return tsubst_copy (t, args, complain, in_decl);
13601 op1 = TREE_OPERAND (t, 0);
13604 /* When there are no ARGS, we are trying to evaluate a
13605 non-dependent expression from the parser. Trying to do
13606 the substitutions may not work. */
13608 op1 = TREE_TYPE (op1);
13612 ++cp_unevaluated_operand;
13613 ++c_inhibit_evaluation_warnings;
13614 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13615 /*function_p=*/false,
13616 /*integral_constant_expression_p=*/false);
13617 --cp_unevaluated_operand;
13618 --c_inhibit_evaluation_warnings;
13621 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
13622 complain & tf_error);
13624 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
13625 complain & tf_error);
13627 case AT_ENCODE_EXPR:
13629 op1 = TREE_OPERAND (t, 0);
13630 ++cp_unevaluated_operand;
13631 ++c_inhibit_evaluation_warnings;
13632 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13633 /*function_p=*/false,
13634 /*integral_constant_expression_p=*/false);
13635 --cp_unevaluated_operand;
13636 --c_inhibit_evaluation_warnings;
13637 return objc_build_encode_expr (op1);
13640 case NOEXCEPT_EXPR:
13641 op1 = TREE_OPERAND (t, 0);
13642 ++cp_unevaluated_operand;
13643 ++c_inhibit_evaluation_warnings;
13644 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13645 /*function_p=*/false,
13646 /*integral_constant_expression_p=*/false);
13647 --cp_unevaluated_operand;
13648 --c_inhibit_evaluation_warnings;
13649 return finish_noexcept_expr (op1, complain);
13653 tree r = build_x_modify_expr
13654 (RECUR (TREE_OPERAND (t, 0)),
13655 TREE_CODE (TREE_OPERAND (t, 1)),
13656 RECUR (TREE_OPERAND (t, 2)),
13658 /* TREE_NO_WARNING must be set if either the expression was
13659 parenthesized or it uses an operator such as >>= rather
13660 than plain assignment. In the former case, it was already
13661 set and must be copied. In the latter case,
13662 build_x_modify_expr sets it and it must not be reset
13664 if (TREE_NO_WARNING (t))
13665 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13670 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13671 args, complain, in_decl);
13672 /* Remember that there was a reference to this entity. */
13675 return build_x_arrow (op1);
13679 tree placement = RECUR (TREE_OPERAND (t, 0));
13680 tree init = RECUR (TREE_OPERAND (t, 3));
13681 VEC(tree,gc) *placement_vec;
13682 VEC(tree,gc) *init_vec;
13685 if (placement == NULL_TREE)
13686 placement_vec = NULL;
13689 placement_vec = make_tree_vector ();
13690 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
13691 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
13694 /* If there was an initializer in the original tree, but it
13695 instantiated to an empty list, then we should pass a
13696 non-NULL empty vector to tell build_new that it was an
13697 empty initializer() rather than no initializer. This can
13698 only happen when the initializer is a pack expansion whose
13699 parameter packs are of length zero. */
13700 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
13704 init_vec = make_tree_vector ();
13705 if (init == void_zero_node)
13706 gcc_assert (init_vec != NULL);
13709 for (; init != NULL_TREE; init = TREE_CHAIN (init))
13710 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
13714 ret = build_new (&placement_vec,
13715 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
13716 RECUR (TREE_OPERAND (t, 2)),
13718 NEW_EXPR_USE_GLOBAL (t),
13721 if (placement_vec != NULL)
13722 release_tree_vector (placement_vec);
13723 if (init_vec != NULL)
13724 release_tree_vector (init_vec);
13730 return delete_sanity
13731 (RECUR (TREE_OPERAND (t, 0)),
13732 RECUR (TREE_OPERAND (t, 1)),
13733 DELETE_EXPR_USE_VEC (t),
13734 DELETE_EXPR_USE_GLOBAL (t),
13737 case COMPOUND_EXPR:
13738 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
13739 RECUR (TREE_OPERAND (t, 1)),
13745 VEC(tree,gc) *call_args;
13746 unsigned int nargs, i;
13751 function = CALL_EXPR_FN (t);
13752 /* When we parsed the expression, we determined whether or
13753 not Koenig lookup should be performed. */
13754 koenig_p = KOENIG_LOOKUP_P (t);
13755 if (TREE_CODE (function) == SCOPE_REF)
13757 qualified_p = true;
13758 function = tsubst_qualified_id (function, args, complain, in_decl,
13760 /*address_p=*/false);
13762 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE)
13764 /* Do nothing; calling tsubst_copy_and_build on an identifier
13765 would incorrectly perform unqualified lookup again.
13767 Note that we can also have an IDENTIFIER_NODE if the earlier
13768 unqualified lookup found a member function; in that case
13769 koenig_p will be false and we do want to do the lookup
13770 again to find the instantiated member function.
13772 FIXME but doing that causes c++/15272, so we need to stop
13773 using IDENTIFIER_NODE in that situation. */
13774 qualified_p = false;
13778 if (TREE_CODE (function) == COMPONENT_REF)
13780 tree op = TREE_OPERAND (function, 1);
13782 qualified_p = (TREE_CODE (op) == SCOPE_REF
13783 || (BASELINK_P (op)
13784 && BASELINK_QUALIFIED_P (op)));
13787 qualified_p = false;
13789 function = tsubst_copy_and_build (function, args, complain,
13792 integral_constant_expression_p);
13794 if (BASELINK_P (function))
13795 qualified_p = true;
13798 nargs = call_expr_nargs (t);
13799 call_args = make_tree_vector ();
13800 for (i = 0; i < nargs; ++i)
13802 tree arg = CALL_EXPR_ARG (t, i);
13804 if (!PACK_EXPANSION_P (arg))
13805 VEC_safe_push (tree, gc, call_args,
13806 RECUR (CALL_EXPR_ARG (t, i)));
13809 /* Expand the pack expansion and push each entry onto
13811 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
13812 if (TREE_CODE (arg) == TREE_VEC)
13814 unsigned int len, j;
13816 len = TREE_VEC_LENGTH (arg);
13817 for (j = 0; j < len; ++j)
13819 tree value = TREE_VEC_ELT (arg, j);
13820 if (value != NULL_TREE)
13821 value = convert_from_reference (value);
13822 VEC_safe_push (tree, gc, call_args, value);
13827 /* A partial substitution. Add one entry. */
13828 VEC_safe_push (tree, gc, call_args, arg);
13833 /* We do not perform argument-dependent lookup if normal
13834 lookup finds a non-function, in accordance with the
13835 expected resolution of DR 218. */
13837 && ((is_overloaded_fn (function)
13838 /* If lookup found a member function, the Koenig lookup is
13839 not appropriate, even if an unqualified-name was used
13840 to denote the function. */
13841 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
13842 || TREE_CODE (function) == IDENTIFIER_NODE)
13843 /* Only do this when substitution turns a dependent call
13844 into a non-dependent call. */
13845 && type_dependent_expression_p_push (t)
13846 && !any_type_dependent_arguments_p (call_args))
13847 function = perform_koenig_lookup (function, call_args, false,
13850 if (TREE_CODE (function) == IDENTIFIER_NODE
13851 && !any_type_dependent_arguments_p (call_args))
13853 if (koenig_p && (complain & tf_warning_or_error))
13855 /* For backwards compatibility and good diagnostics, try
13856 the unqualified lookup again if we aren't in SFINAE
13858 tree unq = (tsubst_copy_and_build
13859 (function, args, complain, in_decl, true,
13860 integral_constant_expression_p));
13861 if (unq == error_mark_node)
13862 return error_mark_node;
13864 if (unq != function)
13867 if (TREE_CODE (fn) == INDIRECT_REF)
13868 fn = TREE_OPERAND (fn, 0);
13869 if (TREE_CODE (fn) == COMPONENT_REF)
13870 fn = TREE_OPERAND (fn, 1);
13871 if (is_overloaded_fn (fn))
13872 fn = get_first_fn (fn);
13873 permerror (EXPR_LOC_OR_HERE (t),
13874 "%qD was not declared in this scope, "
13875 "and no declarations were found by "
13876 "argument-dependent lookup at the point "
13877 "of instantiation", function);
13879 /* Can't say anything more. */;
13880 else if (DECL_CLASS_SCOPE_P (fn))
13882 inform (EXPR_LOC_OR_HERE (t),
13883 "declarations in dependent base %qT are "
13884 "not found by unqualified lookup",
13885 DECL_CLASS_CONTEXT (fn));
13886 if (current_class_ptr)
13887 inform (EXPR_LOC_OR_HERE (t),
13888 "use %<this->%D%> instead", function);
13890 inform (EXPR_LOC_OR_HERE (t),
13891 "use %<%T::%D%> instead",
13892 current_class_name, function);
13895 inform (0, "%q+D declared here, later in the "
13896 "translation unit", fn);
13900 if (TREE_CODE (function) == IDENTIFIER_NODE)
13902 unqualified_name_lookup_error (function);
13903 release_tree_vector (call_args);
13904 return error_mark_node;
13908 /* Remember that there was a reference to this entity. */
13909 if (DECL_P (function))
13910 mark_used (function);
13912 if (TREE_CODE (function) == OFFSET_REF)
13913 ret = build_offset_ref_call_from_tree (function, &call_args);
13914 else if (TREE_CODE (function) == COMPONENT_REF)
13916 tree instance = TREE_OPERAND (function, 0);
13917 tree fn = TREE_OPERAND (function, 1);
13919 if (processing_template_decl
13920 && (type_dependent_expression_p (instance)
13921 || (!BASELINK_P (fn)
13922 && TREE_CODE (fn) != FIELD_DECL)
13923 || type_dependent_expression_p (fn)
13924 || any_type_dependent_arguments_p (call_args)))
13925 ret = build_nt_call_vec (function, call_args);
13926 else if (!BASELINK_P (fn))
13927 ret = finish_call_expr (function, &call_args,
13928 /*disallow_virtual=*/false,
13929 /*koenig_p=*/false,
13932 ret = (build_new_method_call
13934 &call_args, NULL_TREE,
13935 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
13940 ret = finish_call_expr (function, &call_args,
13941 /*disallow_virtual=*/qualified_p,
13945 release_tree_vector (call_args);
13951 return build_x_conditional_expr
13952 (RECUR (TREE_OPERAND (t, 0)),
13953 RECUR (TREE_OPERAND (t, 1)),
13954 RECUR (TREE_OPERAND (t, 2)),
13957 case PSEUDO_DTOR_EXPR:
13958 return finish_pseudo_destructor_expr
13959 (RECUR (TREE_OPERAND (t, 0)),
13960 RECUR (TREE_OPERAND (t, 1)),
13961 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl));
13965 tree purpose, value, chain;
13967 if (t == void_list_node)
13970 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
13971 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
13973 /* We have pack expansions, so expand those and
13974 create a new list out of it. */
13975 tree purposevec = NULL_TREE;
13976 tree valuevec = NULL_TREE;
13980 /* Expand the argument expressions. */
13981 if (TREE_PURPOSE (t))
13982 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
13983 complain, in_decl);
13984 if (TREE_VALUE (t))
13985 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
13986 complain, in_decl);
13988 /* Build the rest of the list. */
13989 chain = TREE_CHAIN (t);
13990 if (chain && chain != void_type_node)
13991 chain = RECUR (chain);
13993 /* Determine the number of arguments. */
13994 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
13996 len = TREE_VEC_LENGTH (purposevec);
13997 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
13999 else if (TREE_CODE (valuevec) == TREE_VEC)
14000 len = TREE_VEC_LENGTH (valuevec);
14003 /* Since we only performed a partial substitution into
14004 the argument pack, we only return a single list
14006 if (purposevec == TREE_PURPOSE (t)
14007 && valuevec == TREE_VALUE (t)
14008 && chain == TREE_CHAIN (t))
14011 return tree_cons (purposevec, valuevec, chain);
14014 /* Convert the argument vectors into a TREE_LIST */
14018 /* Grab the Ith values. */
14020 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
14023 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
14026 /* Build the list (backwards). */
14027 chain = tree_cons (purpose, value, chain);
14033 purpose = TREE_PURPOSE (t);
14035 purpose = RECUR (purpose);
14036 value = TREE_VALUE (t);
14038 value = RECUR (value);
14039 chain = TREE_CHAIN (t);
14040 if (chain && chain != void_type_node)
14041 chain = RECUR (chain);
14042 if (purpose == TREE_PURPOSE (t)
14043 && value == TREE_VALUE (t)
14044 && chain == TREE_CHAIN (t))
14046 return tree_cons (purpose, value, chain);
14049 case COMPONENT_REF:
14055 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
14056 args, complain, in_decl);
14057 /* Remember that there was a reference to this entity. */
14058 if (DECL_P (object))
14059 mark_used (object);
14060 object_type = TREE_TYPE (object);
14062 member = TREE_OPERAND (t, 1);
14063 if (BASELINK_P (member))
14064 member = tsubst_baselink (member,
14065 non_reference (TREE_TYPE (object)),
14066 args, complain, in_decl);
14068 member = tsubst_copy (member, args, complain, in_decl);
14069 if (member == error_mark_node)
14070 return error_mark_node;
14072 if (type_dependent_expression_p (object))
14073 /* We can't do much here. */;
14074 else if (!CLASS_TYPE_P (object_type))
14076 if (SCALAR_TYPE_P (object_type))
14078 tree s = NULL_TREE;
14079 tree dtor = member;
14081 if (TREE_CODE (dtor) == SCOPE_REF)
14083 s = TREE_OPERAND (dtor, 0);
14084 dtor = TREE_OPERAND (dtor, 1);
14086 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
14088 dtor = TREE_OPERAND (dtor, 0);
14090 return finish_pseudo_destructor_expr (object, s, dtor);
14094 else if (TREE_CODE (member) == SCOPE_REF
14095 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
14097 /* Lookup the template functions now that we know what the
14099 tree scope = TREE_OPERAND (member, 0);
14100 tree tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
14101 tree args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
14102 member = lookup_qualified_name (scope, tmpl,
14103 /*is_type_p=*/false,
14104 /*complain=*/false);
14105 if (BASELINK_P (member))
14107 BASELINK_FUNCTIONS (member)
14108 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
14110 member = (adjust_result_of_qualified_name_lookup
14111 (member, BINFO_TYPE (BASELINK_BINFO (member)),
14116 qualified_name_lookup_error (scope, tmpl, member,
14118 return error_mark_node;
14121 else if (TREE_CODE (member) == SCOPE_REF
14122 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
14123 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
14125 if (complain & tf_error)
14127 if (TYPE_P (TREE_OPERAND (member, 0)))
14128 error ("%qT is not a class or namespace",
14129 TREE_OPERAND (member, 0));
14131 error ("%qD is not a class or namespace",
14132 TREE_OPERAND (member, 0));
14134 return error_mark_node;
14136 else if (TREE_CODE (member) == FIELD_DECL)
14137 return finish_non_static_data_member (member, object, NULL_TREE);
14139 return finish_class_member_access_expr (object, member,
14140 /*template_p=*/false,
14146 (RECUR (TREE_OPERAND (t, 0)));
14150 VEC(constructor_elt,gc) *n;
14151 constructor_elt *ce;
14152 unsigned HOST_WIDE_INT idx;
14153 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
14154 bool process_index_p;
14156 bool need_copy_p = false;
14159 if (type == error_mark_node)
14160 return error_mark_node;
14162 /* digest_init will do the wrong thing if we let it. */
14163 if (type && TYPE_PTRMEMFUNC_P (type))
14166 /* We do not want to process the index of aggregate
14167 initializers as they are identifier nodes which will be
14168 looked up by digest_init. */
14169 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
14171 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
14172 newlen = VEC_length (constructor_elt, n);
14173 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
14175 if (ce->index && process_index_p)
14176 ce->index = RECUR (ce->index);
14178 if (PACK_EXPANSION_P (ce->value))
14180 /* Substitute into the pack expansion. */
14181 ce->value = tsubst_pack_expansion (ce->value, args, complain,
14184 if (ce->value == error_mark_node
14185 || PACK_EXPANSION_P (ce->value))
14187 else if (TREE_VEC_LENGTH (ce->value) == 1)
14188 /* Just move the argument into place. */
14189 ce->value = TREE_VEC_ELT (ce->value, 0);
14192 /* Update the length of the final CONSTRUCTOR
14193 arguments vector, and note that we will need to
14195 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
14196 need_copy_p = true;
14200 ce->value = RECUR (ce->value);
14205 VEC(constructor_elt,gc) *old_n = n;
14207 n = VEC_alloc (constructor_elt, gc, newlen);
14208 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
14210 if (TREE_CODE (ce->value) == TREE_VEC)
14212 int i, len = TREE_VEC_LENGTH (ce->value);
14213 for (i = 0; i < len; ++i)
14214 CONSTRUCTOR_APPEND_ELT (n, 0,
14215 TREE_VEC_ELT (ce->value, i));
14218 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
14222 r = build_constructor (init_list_type_node, n);
14223 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
14225 if (TREE_HAS_CONSTRUCTOR (t))
14226 return finish_compound_literal (type, r, complain);
14228 TREE_TYPE (r) = type;
14234 tree operand_0 = TREE_OPERAND (t, 0);
14235 if (TYPE_P (operand_0))
14237 operand_0 = tsubst (operand_0, args, complain, in_decl);
14238 return get_typeid (operand_0);
14242 operand_0 = RECUR (operand_0);
14243 return build_typeid (operand_0);
14254 tree r = tsubst_copy (t, args, complain, in_decl);
14256 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
14257 /* If the original type was a reference, we'll be wrapped in
14258 the appropriate INDIRECT_REF. */
14259 r = convert_from_reference (r);
14264 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
14265 tsubst (TREE_TYPE (t), args, complain, in_decl));
14267 case OFFSETOF_EXPR:
14268 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
14272 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
14273 complain, in_decl);
14275 tree type2 = TRAIT_EXPR_TYPE2 (t);
14277 type2 = tsubst_copy (type2, args, complain, in_decl);
14279 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
14284 tree old_stmt_expr = cur_stmt_expr;
14285 tree stmt_expr = begin_stmt_expr ();
14287 cur_stmt_expr = stmt_expr;
14288 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
14289 integral_constant_expression_p);
14290 stmt_expr = finish_stmt_expr (stmt_expr, false);
14291 cur_stmt_expr = old_stmt_expr;
14293 /* If the resulting list of expression statement is empty,
14294 fold it further into void_zero_node. */
14295 if (empty_expr_stmt_p (stmt_expr))
14296 stmt_expr = void_zero_node;
14302 t = tsubst_copy (t, args, complain, in_decl);
14303 /* As in finish_id_expression, we resolve enumeration constants
14304 to their underlying values. */
14305 if (TREE_CODE (t) == CONST_DECL && !processing_template_decl)
14307 used_types_insert (TREE_TYPE (t));
14308 return DECL_INITIAL (t);
14314 tree r = build_lambda_expr ();
14316 tree type = tsubst (LAMBDA_EXPR_CLOSURE (t), args, complain, NULL_TREE);
14317 LAMBDA_EXPR_CLOSURE (r) = type;
14318 CLASSTYPE_LAMBDA_EXPR (type) = r;
14320 LAMBDA_EXPR_LOCATION (r)
14321 = LAMBDA_EXPR_LOCATION (t);
14322 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
14323 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
14324 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
14325 LAMBDA_EXPR_DISCRIMINATOR (r)
14326 = (LAMBDA_EXPR_DISCRIMINATOR (t));
14327 LAMBDA_EXPR_EXTRA_SCOPE (r)
14328 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
14329 if (LAMBDA_EXPR_RETURN_TYPE (t) == dependent_lambda_return_type_node)
14331 LAMBDA_EXPR_RETURN_TYPE (r) = dependent_lambda_return_type_node;
14332 LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (r) = true;
14335 LAMBDA_EXPR_RETURN_TYPE (r)
14336 = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
14338 gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (t) == NULL_TREE
14339 && LAMBDA_EXPR_PENDING_PROXIES (t) == NULL);
14341 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
14342 determine_visibility (TYPE_NAME (type));
14343 /* Now that we know visibility, instantiate the type so we have a
14344 declaration of the op() for later calls to lambda_function. */
14345 complete_type (type);
14347 /* The capture list refers to closure members, so this needs to
14348 wait until after we finish instantiating the type. */
14349 LAMBDA_EXPR_CAPTURE_LIST (r)
14350 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
14352 return build_lambda_object (r);
14356 /* We can get here for a constant initializer of non-dependent type.
14357 FIXME stop folding in cp_parser_initializer_clause. */
14358 gcc_assert (TREE_CONSTANT (t));
14360 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t)));
14361 TREE_CONSTANT (r) = true;
14365 case TRANSACTION_EXPR:
14366 return tsubst_expr(t, args, complain, in_decl,
14367 integral_constant_expression_p);
14370 /* Handle Objective-C++ constructs, if appropriate. */
14373 = objcp_tsubst_copy_and_build (t, args, complain,
14374 in_decl, /*function_p=*/false);
14378 return tsubst_copy (t, args, complain, in_decl);
14384 /* Verify that the instantiated ARGS are valid. For type arguments,
14385 make sure that the type's linkage is ok. For non-type arguments,
14386 make sure they are constants if they are integral or enumerations.
14387 Emit an error under control of COMPLAIN, and return TRUE on error. */
14390 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
14392 if (ARGUMENT_PACK_P (t))
14394 tree vec = ARGUMENT_PACK_ARGS (t);
14395 int len = TREE_VEC_LENGTH (vec);
14396 bool result = false;
14399 for (i = 0; i < len; ++i)
14400 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
14404 else if (TYPE_P (t))
14406 /* [basic.link]: A name with no linkage (notably, the name
14407 of a class or enumeration declared in a local scope)
14408 shall not be used to declare an entity with linkage.
14409 This implies that names with no linkage cannot be used as
14412 DR 757 relaxes this restriction for C++0x. */
14413 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
14414 : no_linkage_check (t, /*relaxed_p=*/false));
14418 /* DR 488 makes use of a type with no linkage cause
14419 type deduction to fail. */
14420 if (complain & tf_error)
14422 if (TYPE_ANONYMOUS_P (nt))
14423 error ("%qT is/uses anonymous type", t);
14425 error ("template argument for %qD uses local type %qT",
14430 /* In order to avoid all sorts of complications, we do not
14431 allow variably-modified types as template arguments. */
14432 else if (variably_modified_type_p (t, NULL_TREE))
14434 if (complain & tf_error)
14435 error ("%qT is a variably modified type", t);
14439 /* A non-type argument of integral or enumerated type must be a
14441 else if (TREE_TYPE (t)
14442 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
14443 && !TREE_CONSTANT (t))
14445 if (complain & tf_error)
14446 error ("integral expression %qE is not constant", t);
14453 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
14455 int ix, len = DECL_NTPARMS (tmpl);
14456 bool result = false;
14458 for (ix = 0; ix != len; ix++)
14460 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
14463 if (result && (complain & tf_error))
14464 error (" trying to instantiate %qD", tmpl);
14468 /* In C++0x, it's possible to have a function template whose type depends
14469 on itself recursively. This is most obvious with decltype, but can also
14470 occur with enumeration scope (c++/48969). So we need to catch infinite
14471 recursion and reject the substitution at deduction time; this function
14472 will return error_mark_node for any repeated substitution.
14474 This also catches excessive recursion such as when f<N> depends on
14475 f<N-1> across all integers, and returns error_mark_node for all the
14476 substitutions back up to the initial one.
14478 This is, of course, not reentrant. */
14481 deduction_tsubst_fntype (tree fn, tree targs, tsubst_flags_t complain)
14483 static bool excessive_deduction_depth;
14484 static int deduction_depth;
14485 struct pending_template *old_last_pend = last_pending_template;
14486 struct tinst_level *old_error_tinst = last_error_tinst_level;
14488 tree fntype = TREE_TYPE (fn);
14492 if (excessive_deduction_depth)
14493 return error_mark_node;
14495 tinst = build_tree_list (fn, targs);
14496 if (!push_tinst_level (tinst))
14498 excessive_deduction_depth = true;
14500 return error_mark_node;
14503 input_location = DECL_SOURCE_LOCATION (fn);
14505 push_deduction_access_scope (fn);
14506 r = tsubst (fntype, targs, complain, NULL_TREE);
14507 pop_deduction_access_scope (fn);
14510 if (excessive_deduction_depth)
14512 r = error_mark_node;
14513 if (deduction_depth == 0)
14514 /* Reset once we're all the way out. */
14515 excessive_deduction_depth = false;
14518 pop_tinst_level ();
14519 /* We can't free this if a pending_template entry or last_error_tinst_level
14520 is pointing at it. */
14521 if (last_pending_template == old_last_pend
14522 && last_error_tinst_level == old_error_tinst)
14527 /* Instantiate the indicated variable or function template TMPL with
14528 the template arguments in TARG_PTR. */
14531 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
14533 tree targ_ptr = orig_args;
14538 if (tmpl == error_mark_node)
14539 return error_mark_node;
14541 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
14543 /* If this function is a clone, handle it specially. */
14544 if (DECL_CLONED_FUNCTION_P (tmpl))
14549 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
14550 DECL_CLONED_FUNCTION. */
14551 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
14552 targ_ptr, complain);
14553 if (spec == error_mark_node)
14554 return error_mark_node;
14556 /* Look for the clone. */
14557 FOR_EACH_CLONE (clone, spec)
14558 if (DECL_NAME (clone) == DECL_NAME (tmpl))
14560 /* We should always have found the clone by now. */
14561 gcc_unreachable ();
14565 /* Check to see if we already have this specialization. */
14566 gen_tmpl = most_general_template (tmpl);
14567 if (tmpl != gen_tmpl)
14568 /* The TMPL is a partial instantiation. To get a full set of
14569 arguments we must add the arguments used to perform the
14570 partial instantiation. */
14571 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
14574 /* It would be nice to avoid hashing here and then again in tsubst_decl,
14575 but it doesn't seem to be on the hot path. */
14576 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
14578 gcc_assert (tmpl == gen_tmpl
14579 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
14581 || fndecl == NULL_TREE);
14583 if (spec != NULL_TREE)
14586 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
14588 return error_mark_node;
14590 /* We are building a FUNCTION_DECL, during which the access of its
14591 parameters and return types have to be checked. However this
14592 FUNCTION_DECL which is the desired context for access checking
14593 is not built yet. We solve this chicken-and-egg problem by
14594 deferring all checks until we have the FUNCTION_DECL. */
14595 push_deferring_access_checks (dk_deferred);
14597 /* Instantiation of the function happens in the context of the function
14598 template, not the context of the overload resolution we're doing. */
14599 push_to_top_level ();
14600 if (DECL_CLASS_SCOPE_P (gen_tmpl))
14602 tree ctx = tsubst (DECL_CONTEXT (gen_tmpl), targ_ptr,
14603 complain, gen_tmpl);
14604 push_nested_class (ctx);
14606 /* Substitute template parameters to obtain the specialization. */
14607 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
14608 targ_ptr, complain, gen_tmpl);
14609 if (DECL_CLASS_SCOPE_P (gen_tmpl))
14610 pop_nested_class ();
14611 pop_from_top_level ();
14613 if (fndecl == error_mark_node)
14614 return error_mark_node;
14616 /* Now we know the specialization, compute access previously
14618 push_access_scope (fndecl);
14620 /* Some typedefs referenced from within the template code need to be access
14621 checked at template instantiation time, i.e now. These types were
14622 added to the template at parsing time. Let's get those and perfom
14623 the acces checks then. */
14624 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
14625 perform_deferred_access_checks ();
14626 pop_access_scope (fndecl);
14627 pop_deferring_access_checks ();
14629 /* The DECL_TI_TEMPLATE should always be the immediate parent
14630 template, not the most general template. */
14631 DECL_TI_TEMPLATE (fndecl) = tmpl;
14633 /* If we've just instantiated the main entry point for a function,
14634 instantiate all the alternate entry points as well. We do this
14635 by cloning the instantiation of the main entry point, not by
14636 instantiating the template clones. */
14637 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
14638 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
14643 /* Wrapper for instantiate_template_1. */
14646 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
14649 timevar_push (TV_TEMPLATE_INST);
14650 ret = instantiate_template_1 (tmpl, orig_args, complain);
14651 timevar_pop (TV_TEMPLATE_INST);
14655 /* We're going to do deduction substitution on the type of TMPL, a function
14656 template. In C++11 mode, push into that access scope. In C++03 mode,
14657 disable access checking. */
14660 push_deduction_access_scope (tree tmpl)
14662 if (cxx_dialect >= cxx0x)
14664 int ptd = processing_template_decl;
14665 push_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14666 /* Preserve processing_template_decl across push_to_top_level. */
14667 if (ptd && !processing_template_decl)
14668 ++processing_template_decl;
14671 push_deferring_access_checks (dk_no_check);
14674 /* And pop back out. */
14677 pop_deduction_access_scope (tree tmpl)
14679 if (cxx_dialect >= cxx0x)
14680 pop_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14682 pop_deferring_access_checks ();
14685 /* PARM is a template parameter pack for FN. Returns true iff
14686 PARM is used in a deducible way in the argument list of FN. */
14689 pack_deducible_p (tree parm, tree fn)
14691 tree t = FUNCTION_FIRST_USER_PARMTYPE (fn);
14692 for (; t; t = TREE_CHAIN (t))
14694 tree type = TREE_VALUE (t);
14696 if (!PACK_EXPANSION_P (type))
14698 for (packs = PACK_EXPANSION_PARAMETER_PACKS (type);
14699 packs; packs = TREE_CHAIN (packs))
14700 if (TREE_VALUE (packs) == parm)
14702 /* The template parameter pack is used in a function parameter
14703 pack. If this is the end of the parameter list, the
14704 template parameter pack is deducible. */
14705 if (TREE_CHAIN (t) == void_list_node)
14708 /* Otherwise, not. Well, it could be deduced from
14709 a non-pack parameter, but doing so would end up with
14710 a deduction mismatch, so don't bother. */
14714 /* The template parameter pack isn't used in any function parameter
14715 packs, but it might be used deeper, e.g. tuple<Args...>. */
14719 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
14720 NARGS elements of the arguments that are being used when calling
14721 it. TARGS is a vector into which the deduced template arguments
14724 Return zero for success, 2 for an incomplete match that doesn't resolve
14725 all the types, and 1 for complete failure. An error message will be
14726 printed only for an incomplete match.
14728 If FN is a conversion operator, or we are trying to produce a specific
14729 specialization, RETURN_TYPE is the return type desired.
14731 The EXPLICIT_TARGS are explicit template arguments provided via a
14734 The parameter STRICT is one of:
14737 We are deducing arguments for a function call, as in
14738 [temp.deduct.call].
14741 We are deducing arguments for a conversion function, as in
14742 [temp.deduct.conv].
14745 We are deducing arguments when doing an explicit instantiation
14746 as in [temp.explicit], when determining an explicit specialization
14747 as in [temp.expl.spec], or when taking the address of a function
14748 template, as in [temp.deduct.funcaddr]. */
14751 fn_type_unification (tree fn,
14752 tree explicit_targs,
14755 unsigned int nargs,
14757 unification_kind_t strict,
14765 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
14767 fntype = TREE_TYPE (fn);
14768 if (explicit_targs)
14772 The specified template arguments must match the template
14773 parameters in kind (i.e., type, nontype, template), and there
14774 must not be more arguments than there are parameters;
14775 otherwise type deduction fails.
14777 Nontype arguments must match the types of the corresponding
14778 nontype template parameters, or must be convertible to the
14779 types of the corresponding nontype parameters as specified in
14780 _temp.arg.nontype_, otherwise type deduction fails.
14782 All references in the function type of the function template
14783 to the corresponding template parameters are replaced by the
14784 specified template argument values. If a substitution in a
14785 template parameter or in the function type of the function
14786 template results in an invalid type, type deduction fails. */
14787 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
14788 int i, len = TREE_VEC_LENGTH (tparms);
14789 tree converted_args;
14790 bool incomplete = false;
14792 if (explicit_targs == error_mark_node)
14793 return unify_invalid (explain_p);
14796 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE,
14798 ? tf_warning_or_error
14800 /*require_all_args=*/false,
14801 /*use_default_args=*/false));
14802 if (converted_args == error_mark_node)
14805 /* Substitute the explicit args into the function type. This is
14806 necessary so that, for instance, explicitly declared function
14807 arguments can match null pointed constants. If we were given
14808 an incomplete set of explicit args, we must not do semantic
14809 processing during substitution as we could create partial
14811 for (i = 0; i < len; i++)
14813 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14814 bool parameter_pack = false;
14815 tree targ = TREE_VEC_ELT (converted_args, i);
14817 /* Dig out the actual parm. */
14818 if (TREE_CODE (parm) == TYPE_DECL
14819 || TREE_CODE (parm) == TEMPLATE_DECL)
14821 parm = TREE_TYPE (parm);
14822 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
14824 else if (TREE_CODE (parm) == PARM_DECL)
14826 parm = DECL_INITIAL (parm);
14827 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
14830 if (!parameter_pack && targ == NULL_TREE)
14831 /* No explicit argument for this template parameter. */
14834 if (parameter_pack && pack_deducible_p (parm, fn))
14836 /* Mark the argument pack as "incomplete". We could
14837 still deduce more arguments during unification.
14838 We remove this mark in type_unification_real. */
14841 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
14842 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
14843 = ARGUMENT_PACK_ARGS (targ);
14846 /* We have some incomplete argument packs. */
14851 processing_template_decl += incomplete;
14852 fntype = deduction_tsubst_fntype (fn, converted_args,
14854 ? tf_warning_or_error
14856 processing_template_decl -= incomplete;
14858 if (fntype == error_mark_node)
14861 /* Place the explicitly specified arguments in TARGS. */
14862 for (i = NUM_TMPL_ARGS (converted_args); i--;)
14863 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
14866 /* Never do unification on the 'this' parameter. */
14867 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
14873 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
14874 new_args = XALLOCAVEC (tree, nargs + 1);
14875 new_args[0] = return_type;
14876 memcpy (new_args + 1, args, nargs * sizeof (tree));
14881 /* We allow incomplete unification without an error message here
14882 because the standard doesn't seem to explicitly prohibit it. Our
14883 callers must be ready to deal with unification failures in any
14885 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
14886 targs, parms, args, nargs, /*subr=*/0,
14887 strict, flags, explain_p);
14889 /* Now that we have bindings for all of the template arguments,
14890 ensure that the arguments deduced for the template template
14891 parameters have compatible template parameter lists. We cannot
14892 check this property before we have deduced all template
14893 arguments, because the template parameter types of a template
14894 template parameter might depend on prior template parameters
14895 deduced after the template template parameter. The following
14896 ill-formed example illustrates this issue:
14898 template<typename T, template<T> class C> void f(C<5>, T);
14900 template<int N> struct X {};
14903 f(X<5>(), 5l); // error: template argument deduction fails
14906 The template parameter list of 'C' depends on the template type
14907 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
14908 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
14909 time that we deduce 'C'. */
14911 && !template_template_parm_bindings_ok_p
14912 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
14913 return unify_inconsistent_template_template_parameters (explain_p);
14916 /* All is well so far. Now, check:
14920 When all template arguments have been deduced, all uses of
14921 template parameters in nondeduced contexts are replaced with
14922 the corresponding deduced argument values. If the
14923 substitution results in an invalid type, as described above,
14924 type deduction fails. */
14926 tree substed = deduction_tsubst_fntype (fn, targs,
14928 ? tf_warning_or_error
14930 if (substed == error_mark_node)
14933 /* If we're looking for an exact match, check that what we got
14934 is indeed an exact match. It might not be if some template
14935 parameters are used in non-deduced contexts. */
14936 if (strict == DEDUCE_EXACT)
14941 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
14943 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
14944 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
14945 if (!same_type_p (args[i], TREE_VALUE (sarg)))
14946 return unify_type_mismatch (explain_p, args[i],
14947 TREE_VALUE (sarg));
14954 /* Adjust types before performing type deduction, as described in
14955 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
14956 sections are symmetric. PARM is the type of a function parameter
14957 or the return type of the conversion function. ARG is the type of
14958 the argument passed to the call, or the type of the value
14959 initialized with the result of the conversion function.
14960 ARG_EXPR is the original argument expression, which may be null. */
14963 maybe_adjust_types_for_deduction (unification_kind_t strict,
14977 /* Swap PARM and ARG throughout the remainder of this
14978 function; the handling is precisely symmetric since PARM
14979 will initialize ARG rather than vice versa. */
14987 /* Core issue #873: Do the DR606 thing (see below) for these cases,
14988 too, but here handle it by stripping the reference from PARM
14989 rather than by adding it to ARG. */
14990 if (TREE_CODE (*parm) == REFERENCE_TYPE
14991 && TYPE_REF_IS_RVALUE (*parm)
14992 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
14993 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
14994 && TREE_CODE (*arg) == REFERENCE_TYPE
14995 && !TYPE_REF_IS_RVALUE (*arg))
14996 *parm = TREE_TYPE (*parm);
14997 /* Nothing else to do in this case. */
15001 gcc_unreachable ();
15004 if (TREE_CODE (*parm) != REFERENCE_TYPE)
15006 /* [temp.deduct.call]
15008 If P is not a reference type:
15010 --If A is an array type, the pointer type produced by the
15011 array-to-pointer standard conversion (_conv.array_) is
15012 used in place of A for type deduction; otherwise,
15014 --If A is a function type, the pointer type produced by
15015 the function-to-pointer standard conversion
15016 (_conv.func_) is used in place of A for type deduction;
15019 --If A is a cv-qualified type, the top level
15020 cv-qualifiers of A's type are ignored for type
15022 if (TREE_CODE (*arg) == ARRAY_TYPE)
15023 *arg = build_pointer_type (TREE_TYPE (*arg));
15024 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
15025 *arg = build_pointer_type (*arg);
15027 *arg = TYPE_MAIN_VARIANT (*arg);
15030 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
15031 of the form T&&, where T is a template parameter, and the argument
15032 is an lvalue, T is deduced as A& */
15033 if (TREE_CODE (*parm) == REFERENCE_TYPE
15034 && TYPE_REF_IS_RVALUE (*parm)
15035 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
15036 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
15037 && (arg_expr ? real_lvalue_p (arg_expr)
15038 /* try_one_overload doesn't provide an arg_expr, but
15039 functions are always lvalues. */
15040 : TREE_CODE (*arg) == FUNCTION_TYPE))
15041 *arg = build_reference_type (*arg);
15043 /* [temp.deduct.call]
15045 If P is a cv-qualified type, the top level cv-qualifiers
15046 of P's type are ignored for type deduction. If P is a
15047 reference type, the type referred to by P is used for
15049 *parm = TYPE_MAIN_VARIANT (*parm);
15050 if (TREE_CODE (*parm) == REFERENCE_TYPE)
15052 *parm = TREE_TYPE (*parm);
15053 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
15056 /* DR 322. For conversion deduction, remove a reference type on parm
15057 too (which has been swapped into ARG). */
15058 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
15059 *arg = TREE_TYPE (*arg);
15064 /* Subroutine of unify_one_argument. PARM is a function parameter of a
15065 template which does contain any deducible template parameters; check if
15066 ARG is a suitable match for it. STRICT, FLAGS and EXPLAIN_P are as in
15067 unify_one_argument. */
15070 check_non_deducible_conversion (tree parm, tree arg, int strict,
15071 int flags, bool explain_p)
15076 type = TREE_TYPE (arg);
15080 if (same_type_p (parm, type))
15081 return unify_success (explain_p);
15083 if (strict == DEDUCE_CONV)
15085 if (can_convert_arg (type, parm, NULL_TREE, flags))
15086 return unify_success (explain_p);
15088 else if (strict != DEDUCE_EXACT)
15090 if (can_convert_arg (parm, type,
15091 TYPE_P (arg) ? NULL_TREE : arg,
15093 return unify_success (explain_p);
15096 if (strict == DEDUCE_EXACT)
15097 return unify_type_mismatch (explain_p, parm, arg);
15099 return unify_arg_conversion (explain_p, parm, type, arg);
15102 /* Subroutine of type_unification_real and unify_pack_expansion to
15103 handle unification of a single P/A pair. Parameters are as
15104 for those functions. */
15107 unify_one_argument (tree tparms, tree targs, tree parm, tree arg,
15108 int subr, unification_kind_t strict, int flags,
15111 tree arg_expr = NULL_TREE;
15114 if (arg == error_mark_node || parm == error_mark_node)
15115 return unify_invalid (explain_p);
15116 if (arg == unknown_type_node)
15117 /* We can't deduce anything from this, but we might get all the
15118 template args from other function args. */
15119 return unify_success (explain_p);
15121 /* FIXME uses_deducible_template_parms */
15122 if (TYPE_P (parm) && !uses_template_parms (parm))
15123 return check_non_deducible_conversion (parm, arg, strict, flags,
15129 arg_strict = (UNIFY_ALLOW_OUTER_LEVEL
15130 | UNIFY_ALLOW_MORE_CV_QUAL
15131 | UNIFY_ALLOW_DERIVED);
15135 arg_strict = UNIFY_ALLOW_LESS_CV_QUAL;
15139 arg_strict = UNIFY_ALLOW_NONE;
15143 gcc_unreachable ();
15146 /* We only do these transformations if this is the top-level
15147 parameter_type_list in a call or declaration matching; in other
15148 situations (nested function declarators, template argument lists) we
15149 won't be comparing a type to an expression, and we don't do any type
15155 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
15156 if (type_unknown_p (arg))
15158 /* [temp.deduct.type] A template-argument can be
15159 deduced from a pointer to function or pointer
15160 to member function argument if the set of
15161 overloaded functions does not contain function
15162 templates and at most one of a set of
15163 overloaded functions provides a unique
15166 if (resolve_overloaded_unification
15167 (tparms, targs, parm, arg, strict,
15168 arg_strict, explain_p))
15169 return unify_success (explain_p);
15170 return unify_overload_resolution_failure (explain_p, arg);
15174 arg = unlowered_expr_type (arg);
15175 if (arg == error_mark_node)
15176 return unify_invalid (explain_p);
15180 maybe_adjust_types_for_deduction (strict, &parm, &arg, arg_expr);
15183 gcc_assert ((TYPE_P (parm) || TREE_CODE (parm) == TEMPLATE_DECL)
15184 == (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL));
15186 /* For deduction from an init-list we need the actual list. */
15187 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
15189 return unify (tparms, targs, parm, arg, arg_strict, explain_p);
15192 /* Most parms like fn_type_unification.
15194 If SUBR is 1, we're being called recursively (to unify the
15195 arguments of a function or method parameter of a function
15199 type_unification_real (tree tparms,
15203 unsigned int xnargs,
15205 unification_kind_t strict,
15211 int ntparms = TREE_VEC_LENGTH (tparms);
15212 int saw_undeduced = 0;
15215 unsigned int nargs;
15218 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
15219 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
15220 gcc_assert (ntparms > 0);
15222 /* Reset the number of non-defaulted template arguments contained
15224 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
15232 while (parms && parms != void_list_node
15235 parm = TREE_VALUE (parms);
15237 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION
15238 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node))
15239 /* For a function parameter pack that occurs at the end of the
15240 parameter-declaration-list, the type A of each remaining
15241 argument of the call is compared with the type P of the
15242 declarator-id of the function parameter pack. */
15245 parms = TREE_CHAIN (parms);
15247 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION)
15248 /* For a function parameter pack that does not occur at the
15249 end of the parameter-declaration-list, the type of the
15250 parameter pack is a non-deduced context. */
15256 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
15262 && parms != void_list_node
15263 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
15265 /* Unify the remaining arguments with the pack expansion type. */
15267 tree parmvec = make_tree_vec (1);
15269 /* Allocate a TREE_VEC and copy in all of the arguments */
15270 argvec = make_tree_vec (nargs - ia);
15271 for (i = 0; ia < nargs; ++ia, ++i)
15272 TREE_VEC_ELT (argvec, i) = args[ia];
15274 /* Copy the parameter into parmvec. */
15275 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
15276 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
15277 /*subr=*/subr, explain_p))
15280 /* Advance to the end of the list of parameters. */
15281 parms = TREE_CHAIN (parms);
15284 /* Fail if we've reached the end of the parm list, and more args
15285 are present, and the parm list isn't variadic. */
15286 if (ia < nargs && parms == void_list_node)
15287 return unify_too_many_arguments (explain_p, nargs, ia);
15288 /* Fail if parms are left and they don't have default values. */
15289 if (parms && parms != void_list_node
15290 && TREE_PURPOSE (parms) == NULL_TREE)
15292 unsigned int count = nargs;
15294 while (p && p != void_list_node)
15297 p = TREE_CHAIN (p);
15299 return unify_too_few_arguments (explain_p, ia, count);
15304 tsubst_flags_t complain = (explain_p
15305 ? tf_warning_or_error
15308 /* Check to see if we need another pass before we start clearing
15309 ARGUMENT_PACK_INCOMPLETE_P. */
15310 for (i = 0; i < ntparms; i++)
15312 tree targ = TREE_VEC_ELT (targs, i);
15313 tree tparm = TREE_VEC_ELT (tparms, i);
15315 if (targ || tparm == error_mark_node)
15317 tparm = TREE_VALUE (tparm);
15319 /* If this is an undeduced nontype parameter that depends on
15320 a type parameter, try another pass; its type may have been
15321 deduced from a later argument than the one from which
15322 this parameter can be deduced. */
15323 if (TREE_CODE (tparm) == PARM_DECL
15324 && uses_template_parms (TREE_TYPE (tparm))
15325 && !saw_undeduced++)
15329 for (i = 0; i < ntparms; i++)
15331 tree targ = TREE_VEC_ELT (targs, i);
15332 tree tparm = TREE_VEC_ELT (tparms, i);
15334 /* Clear the "incomplete" flags on all argument packs now so that
15335 substituting them into later default arguments works. */
15336 if (targ && ARGUMENT_PACK_P (targ))
15338 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
15339 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
15342 if (targ || tparm == error_mark_node)
15344 tparm = TREE_VALUE (tparm);
15346 /* Core issue #226 (C++0x) [temp.deduct]:
15348 If a template argument has not been deduced, its
15349 default template argument, if any, is used.
15351 When we are in C++98 mode, TREE_PURPOSE will either
15352 be NULL_TREE or ERROR_MARK_NODE, so we do not need
15353 to explicitly check cxx_dialect here. */
15354 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
15356 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
15357 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
15358 location_t save_loc = input_location;
15360 input_location = DECL_SOURCE_LOCATION (parm);
15361 arg = tsubst_template_arg (arg, targs, complain, NULL_TREE);
15362 arg = convert_template_argument (parm, arg, targs, complain,
15364 input_location = save_loc;
15365 if (arg == error_mark_node)
15369 TREE_VEC_ELT (targs, i) = arg;
15370 /* The position of the first default template argument,
15371 is also the number of non-defaulted arguments in TARGS.
15373 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15374 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
15379 /* If the type parameter is a parameter pack, then it will
15380 be deduced to an empty parameter pack. */
15381 if (template_parameter_pack_p (tparm))
15385 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
15387 arg = make_node (NONTYPE_ARGUMENT_PACK);
15388 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
15389 TREE_CONSTANT (arg) = 1;
15392 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
15394 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
15396 TREE_VEC_ELT (targs, i) = arg;
15400 return unify_parameter_deduction_failure (explain_p, tparm);
15403 #ifdef ENABLE_CHECKING
15404 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15405 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
15408 return unify_success (explain_p);
15411 /* Subroutine of type_unification_real. Args are like the variables
15412 at the call site. ARG is an overloaded function (or template-id);
15413 we try deducing template args from each of the overloads, and if
15414 only one succeeds, we go with that. Modifies TARGS and returns
15415 true on success. */
15418 resolve_overloaded_unification (tree tparms,
15422 unification_kind_t strict,
15426 tree tempargs = copy_node (targs);
15428 tree goodfn = NULL_TREE;
15431 if (TREE_CODE (arg) == ADDR_EXPR)
15433 arg = TREE_OPERAND (arg, 0);
15439 if (TREE_CODE (arg) == COMPONENT_REF)
15440 /* Handle `&x' where `x' is some static or non-static member
15442 arg = TREE_OPERAND (arg, 1);
15444 if (TREE_CODE (arg) == OFFSET_REF)
15445 arg = TREE_OPERAND (arg, 1);
15447 /* Strip baselink information. */
15448 if (BASELINK_P (arg))
15449 arg = BASELINK_FUNCTIONS (arg);
15451 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
15453 /* If we got some explicit template args, we need to plug them into
15454 the affected templates before we try to unify, in case the
15455 explicit args will completely resolve the templates in question. */
15458 tree expl_subargs = TREE_OPERAND (arg, 1);
15459 arg = TREE_OPERAND (arg, 0);
15461 for (; arg; arg = OVL_NEXT (arg))
15463 tree fn = OVL_CURRENT (arg);
15464 tree subargs, elem;
15466 if (TREE_CODE (fn) != TEMPLATE_DECL)
15469 ++processing_template_decl;
15470 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15471 expl_subargs, /*check_ret=*/false);
15472 if (subargs && !any_dependent_template_arguments_p (subargs))
15474 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
15475 if (try_one_overload (tparms, targs, tempargs, parm,
15476 elem, strict, sub_strict, addr_p, explain_p)
15477 && (!goodfn || !same_type_p (goodfn, elem)))
15485 --processing_template_decl;
15487 /* If no templates (or more than one) are fully resolved by the
15488 explicit arguments, this template-id is a non-deduced context; it
15489 could still be OK if we deduce all template arguments for the
15490 enclosing call through other arguments. */
15494 else if (TREE_CODE (arg) != OVERLOAD
15495 && TREE_CODE (arg) != FUNCTION_DECL)
15496 /* If ARG is, for example, "(0, &f)" then its type will be unknown
15497 -- but the deduction does not succeed because the expression is
15498 not just the function on its own. */
15501 for (; arg; arg = OVL_NEXT (arg))
15502 if (try_one_overload (tparms, targs, tempargs, parm,
15503 TREE_TYPE (OVL_CURRENT (arg)),
15504 strict, sub_strict, addr_p, explain_p)
15505 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
15507 goodfn = OVL_CURRENT (arg);
15511 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15512 to function or pointer to member function argument if the set of
15513 overloaded functions does not contain function templates and at most
15514 one of a set of overloaded functions provides a unique match.
15516 So if we found multiple possibilities, we return success but don't
15517 deduce anything. */
15521 int i = TREE_VEC_LENGTH (targs);
15523 if (TREE_VEC_ELT (tempargs, i))
15524 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
15532 /* Core DR 115: In contexts where deduction is done and fails, or in
15533 contexts where deduction is not done, if a template argument list is
15534 specified and it, along with any default template arguments, identifies
15535 a single function template specialization, then the template-id is an
15536 lvalue for the function template specialization. */
15539 resolve_nondeduced_context (tree orig_expr)
15541 tree expr, offset, baselink;
15544 if (!type_unknown_p (orig_expr))
15549 offset = NULL_TREE;
15550 baselink = NULL_TREE;
15552 if (TREE_CODE (expr) == ADDR_EXPR)
15554 expr = TREE_OPERAND (expr, 0);
15557 if (TREE_CODE (expr) == OFFSET_REF)
15560 expr = TREE_OPERAND (expr, 1);
15562 if (BASELINK_P (expr))
15565 expr = BASELINK_FUNCTIONS (expr);
15568 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
15571 tree goodfn = NULL_TREE;
15573 /* If we got some explicit template args, we need to plug them into
15574 the affected templates before we try to unify, in case the
15575 explicit args will completely resolve the templates in question. */
15577 tree expl_subargs = TREE_OPERAND (expr, 1);
15578 tree arg = TREE_OPERAND (expr, 0);
15579 tree badfn = NULL_TREE;
15580 tree badargs = NULL_TREE;
15582 for (; arg; arg = OVL_NEXT (arg))
15584 tree fn = OVL_CURRENT (arg);
15585 tree subargs, elem;
15587 if (TREE_CODE (fn) != TEMPLATE_DECL)
15590 ++processing_template_decl;
15591 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15592 expl_subargs, /*check_ret=*/false);
15593 if (subargs && !any_dependent_template_arguments_p (subargs))
15595 elem = instantiate_template (fn, subargs, tf_none);
15596 if (elem == error_mark_node)
15601 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
15607 --processing_template_decl;
15611 mark_used (goodfn);
15614 expr = build_baselink (BASELINK_BINFO (baselink),
15615 BASELINK_ACCESS_BINFO (baselink),
15616 expr, BASELINK_OPTYPE (baselink));
15620 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
15621 expr = build_offset_ref (base, expr, addr);
15624 expr = cp_build_addr_expr (expr, tf_warning_or_error);
15627 else if (good == 0 && badargs)
15628 /* There were no good options and at least one bad one, so let the
15629 user know what the problem is. */
15630 instantiate_template (badfn, badargs, tf_warning_or_error);
15635 /* Subroutine of resolve_overloaded_unification; does deduction for a single
15636 overload. Fills TARGS with any deduced arguments, or error_mark_node if
15637 different overloads deduce different arguments for a given parm.
15638 ADDR_P is true if the expression for which deduction is being
15639 performed was of the form "& fn" rather than simply "fn".
15641 Returns 1 on success. */
15644 try_one_overload (tree tparms,
15649 unification_kind_t strict,
15658 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15659 to function or pointer to member function argument if the set of
15660 overloaded functions does not contain function templates and at most
15661 one of a set of overloaded functions provides a unique match.
15663 So if this is a template, just return success. */
15665 if (uses_template_parms (arg))
15668 if (TREE_CODE (arg) == METHOD_TYPE)
15669 arg = build_ptrmemfunc_type (build_pointer_type (arg));
15671 arg = build_pointer_type (arg);
15673 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
15675 /* We don't copy orig_targs for this because if we have already deduced
15676 some template args from previous args, unify would complain when we
15677 try to deduce a template parameter for the same argument, even though
15678 there isn't really a conflict. */
15679 nargs = TREE_VEC_LENGTH (targs);
15680 tempargs = make_tree_vec (nargs);
15682 if (unify (tparms, tempargs, parm, arg, sub_strict, explain_p))
15685 /* First make sure we didn't deduce anything that conflicts with
15686 explicitly specified args. */
15687 for (i = nargs; i--; )
15689 tree elt = TREE_VEC_ELT (tempargs, i);
15690 tree oldelt = TREE_VEC_ELT (orig_targs, i);
15694 else if (uses_template_parms (elt))
15695 /* Since we're unifying against ourselves, we will fill in
15696 template args used in the function parm list with our own
15697 template parms. Discard them. */
15698 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
15699 else if (oldelt && !template_args_equal (oldelt, elt))
15703 for (i = nargs; i--; )
15705 tree elt = TREE_VEC_ELT (tempargs, i);
15708 TREE_VEC_ELT (targs, i) = elt;
15714 /* PARM is a template class (perhaps with unbound template
15715 parameters). ARG is a fully instantiated type. If ARG can be
15716 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
15717 TARGS are as for unify. */
15720 try_class_unification (tree tparms, tree targs, tree parm, tree arg,
15723 tree copy_of_targs;
15725 if (!CLASSTYPE_TEMPLATE_INFO (arg)
15726 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
15727 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
15730 /* We need to make a new template argument vector for the call to
15731 unify. If we used TARGS, we'd clutter it up with the result of
15732 the attempted unification, even if this class didn't work out.
15733 We also don't want to commit ourselves to all the unifications
15734 we've already done, since unification is supposed to be done on
15735 an argument-by-argument basis. In other words, consider the
15736 following pathological case:
15738 template <int I, int J, int K>
15741 template <int I, int J>
15742 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
15744 template <int I, int J, int K>
15745 void f(S<I, J, K>, S<I, I, I>);
15754 Now, by the time we consider the unification involving `s2', we
15755 already know that we must have `f<0, 0, 0>'. But, even though
15756 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
15757 because there are two ways to unify base classes of S<0, 1, 2>
15758 with S<I, I, I>. If we kept the already deduced knowledge, we
15759 would reject the possibility I=1. */
15760 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
15762 /* If unification failed, we're done. */
15763 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
15764 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE, explain_p))
15770 /* Given a template type PARM and a class type ARG, find the unique
15771 base type in ARG that is an instance of PARM. We do not examine
15772 ARG itself; only its base-classes. If there is not exactly one
15773 appropriate base class, return NULL_TREE. PARM may be the type of
15774 a partial specialization, as well as a plain template type. Used
15777 static enum template_base_result
15778 get_template_base (tree tparms, tree targs, tree parm, tree arg,
15779 bool explain_p, tree *result)
15781 tree rval = NULL_TREE;
15784 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
15786 binfo = TYPE_BINFO (complete_type (arg));
15789 /* The type could not be completed. */
15790 *result = NULL_TREE;
15791 return tbr_incomplete_type;
15794 /* Walk in inheritance graph order. The search order is not
15795 important, and this avoids multiple walks of virtual bases. */
15796 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
15798 tree r = try_class_unification (tparms, targs, parm,
15799 BINFO_TYPE (binfo), explain_p);
15803 /* If there is more than one satisfactory baseclass, then:
15807 If they yield more than one possible deduced A, the type
15811 if (rval && !same_type_p (r, rval))
15813 *result = NULL_TREE;
15814 return tbr_ambiguous_baseclass;
15822 return tbr_success;
15825 /* Returns the level of DECL, which declares a template parameter. */
15828 template_decl_level (tree decl)
15830 switch (TREE_CODE (decl))
15833 case TEMPLATE_DECL:
15834 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
15837 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
15840 gcc_unreachable ();
15845 /* Decide whether ARG can be unified with PARM, considering only the
15846 cv-qualifiers of each type, given STRICT as documented for unify.
15847 Returns nonzero iff the unification is OK on that basis. */
15850 check_cv_quals_for_unify (int strict, tree arg, tree parm)
15852 int arg_quals = cp_type_quals (arg);
15853 int parm_quals = cp_type_quals (parm);
15855 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15856 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15858 /* Although a CVR qualifier is ignored when being applied to a
15859 substituted template parameter ([8.3.2]/1 for example), that
15860 does not allow us to unify "const T" with "int&" because both
15861 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
15862 It is ok when we're allowing additional CV qualifiers
15863 at the outer level [14.8.2.1]/3,1st bullet. */
15864 if ((TREE_CODE (arg) == REFERENCE_TYPE
15865 || TREE_CODE (arg) == FUNCTION_TYPE
15866 || TREE_CODE (arg) == METHOD_TYPE)
15867 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
15870 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
15871 && (parm_quals & TYPE_QUAL_RESTRICT))
15875 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15876 && (arg_quals & parm_quals) != parm_quals)
15879 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
15880 && (parm_quals & arg_quals) != arg_quals)
15886 /* Determines the LEVEL and INDEX for the template parameter PARM. */
15888 template_parm_level_and_index (tree parm, int* level, int* index)
15890 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15891 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15892 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15894 *index = TEMPLATE_TYPE_IDX (parm);
15895 *level = TEMPLATE_TYPE_LEVEL (parm);
15899 *index = TEMPLATE_PARM_IDX (parm);
15900 *level = TEMPLATE_PARM_LEVEL (parm);
15904 #define RECUR_AND_CHECK_FAILURE(TP, TA, P, A, S, EP) \
15906 if (unify (TP, TA, P, A, S, EP)) \
15910 /* Unifies the remaining arguments in PACKED_ARGS with the pack
15911 expansion at the end of PACKED_PARMS. Returns 0 if the type
15912 deduction succeeds, 1 otherwise. STRICT is the same as in
15913 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
15914 call argument list. We'll need to adjust the arguments to make them
15915 types. SUBR tells us if this is from a recursive call to
15916 type_unification_real, or for comparing two template argument
15920 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
15921 tree packed_args, unification_kind_t strict,
15922 bool subr, bool explain_p)
15925 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
15926 tree pattern = PACK_EXPANSION_PATTERN (parm);
15927 tree pack, packs = NULL_TREE;
15928 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
15929 int len = TREE_VEC_LENGTH (packed_args);
15931 /* Determine the parameter packs we will be deducing from the
15932 pattern, and record their current deductions. */
15933 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
15934 pack; pack = TREE_CHAIN (pack))
15936 tree parm_pack = TREE_VALUE (pack);
15939 /* Determine the index and level of this parameter pack. */
15940 template_parm_level_and_index (parm_pack, &level, &idx);
15942 /* Keep track of the parameter packs and their corresponding
15944 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
15945 TREE_TYPE (packs) = make_tree_vec (len - start);
15948 /* Loop through all of the arguments that have not yet been
15949 unified and unify each with the pattern. */
15950 for (i = start; i < len; i++)
15953 bool any_explicit = false;
15954 tree arg = TREE_VEC_ELT (packed_args, i);
15956 /* For each parameter pack, set its TMPL_ARG to either NULL_TREE
15957 or the element of its argument pack at the current index if
15958 this argument was explicitly specified. */
15959 for (pack = packs; pack; pack = TREE_CHAIN (pack))
15963 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
15966 if (TREE_VALUE (pack)
15967 && (pargs = ARGUMENT_PACK_EXPLICIT_ARGS (TREE_VALUE (pack)))
15968 && (i < TREE_VEC_LENGTH (pargs)))
15970 any_explicit = true;
15971 arg = TREE_VEC_ELT (pargs, i);
15973 TMPL_ARG (targs, level, idx) = arg;
15976 /* If we had explicit template arguments, substitute them into the
15977 pattern before deduction. */
15980 /* Some arguments might still be unspecified or dependent. */
15982 ++processing_template_decl;
15983 dependent = any_dependent_template_arguments_p (targs);
15985 --processing_template_decl;
15986 parm = tsubst (pattern, targs,
15987 explain_p ? tf_warning_or_error : tf_none,
15990 --processing_template_decl;
15991 if (parm == error_mark_node)
15997 /* Unify the pattern with the current argument. */
15998 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
15999 LOOKUP_IMPLICIT, explain_p))
16002 /* For each parameter pack, collect the deduced value. */
16003 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16006 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16008 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
16009 TMPL_ARG (targs, level, idx);
16013 /* Verify that the results of unification with the parameter packs
16014 produce results consistent with what we've seen before, and make
16015 the deduced argument packs available. */
16016 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16018 tree old_pack = TREE_VALUE (pack);
16019 tree new_args = TREE_TYPE (pack);
16020 int i, len = TREE_VEC_LENGTH (new_args);
16022 bool nondeduced_p = false;
16024 /* By default keep the original deduced argument pack.
16025 If necessary, more specific code is going to update the
16026 resulting deduced argument later down in this function. */
16027 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16028 TMPL_ARG (targs, level, idx) = old_pack;
16030 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
16031 actually deduce anything. */
16032 for (i = 0; i < len && !nondeduced_p; ++i)
16033 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
16034 nondeduced_p = true;
16038 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
16040 /* If we had fewer function args than explicit template args,
16041 just use the explicits. */
16042 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
16043 int explicit_len = TREE_VEC_LENGTH (explicit_args);
16044 if (len < explicit_len)
16045 new_args = explicit_args;
16051 /* Build the deduced *_ARGUMENT_PACK. */
16052 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
16054 result = make_node (NONTYPE_ARGUMENT_PACK);
16055 TREE_TYPE (result) =
16056 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
16057 TREE_CONSTANT (result) = 1;
16060 result = cxx_make_type (TYPE_ARGUMENT_PACK);
16062 SET_ARGUMENT_PACK_ARGS (result, new_args);
16064 /* Note the deduced argument packs for this parameter
16066 TMPL_ARG (targs, level, idx) = result;
16068 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
16069 && (ARGUMENT_PACK_ARGS (old_pack)
16070 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
16072 /* We only had the explicitly-provided arguments before, but
16073 now we have a complete set of arguments. */
16074 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
16076 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
16077 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
16078 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
16082 tree bad_old_arg = NULL_TREE, bad_new_arg = NULL_TREE;
16083 tree old_args = ARGUMENT_PACK_ARGS (old_pack);
16085 if (!comp_template_args_with_info (old_args, new_args,
16086 &bad_old_arg, &bad_new_arg))
16087 /* Inconsistent unification of this parameter pack. */
16088 return unify_parameter_pack_inconsistent (explain_p,
16094 return unify_success (explain_p);
16097 /* Deduce the value of template parameters. TPARMS is the (innermost)
16098 set of template parameters to a template. TARGS is the bindings
16099 for those template parameters, as determined thus far; TARGS may
16100 include template arguments for outer levels of template parameters
16101 as well. PARM is a parameter to a template function, or a
16102 subcomponent of that parameter; ARG is the corresponding argument.
16103 This function attempts to match PARM with ARG in a manner
16104 consistent with the existing assignments in TARGS. If more values
16105 are deduced, then TARGS is updated.
16107 Returns 0 if the type deduction succeeds, 1 otherwise. The
16108 parameter STRICT is a bitwise or of the following flags:
16111 Require an exact match between PARM and ARG.
16112 UNIFY_ALLOW_MORE_CV_QUAL:
16113 Allow the deduced ARG to be more cv-qualified (by qualification
16114 conversion) than ARG.
16115 UNIFY_ALLOW_LESS_CV_QUAL:
16116 Allow the deduced ARG to be less cv-qualified than ARG.
16117 UNIFY_ALLOW_DERIVED:
16118 Allow the deduced ARG to be a template base class of ARG,
16119 or a pointer to a template base class of the type pointed to by
16121 UNIFY_ALLOW_INTEGER:
16122 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
16123 case for more information.
16124 UNIFY_ALLOW_OUTER_LEVEL:
16125 This is the outermost level of a deduction. Used to determine validity
16126 of qualification conversions. A valid qualification conversion must
16127 have const qualified pointers leading up to the inner type which
16128 requires additional CV quals, except at the outer level, where const
16129 is not required [conv.qual]. It would be normal to set this flag in
16130 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
16131 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
16132 This is the outermost level of a deduction, and PARM can be more CV
16133 qualified at this point.
16134 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
16135 This is the outermost level of a deduction, and PARM can be less CV
16136 qualified at this point. */
16139 unify (tree tparms, tree targs, tree parm, tree arg, int strict,
16145 int strict_in = strict;
16147 /* I don't think this will do the right thing with respect to types.
16148 But the only case I've seen it in so far has been array bounds, where
16149 signedness is the only information lost, and I think that will be
16151 while (TREE_CODE (parm) == NOP_EXPR)
16152 parm = TREE_OPERAND (parm, 0);
16154 if (arg == error_mark_node)
16155 return unify_invalid (explain_p);
16156 if (arg == unknown_type_node
16157 || arg == init_list_type_node)
16158 /* We can't deduce anything from this, but we might get all the
16159 template args from other function args. */
16160 return unify_success (explain_p);
16162 /* If PARM uses template parameters, then we can't bail out here,
16163 even if ARG == PARM, since we won't record unifications for the
16164 template parameters. We might need them if we're trying to
16165 figure out which of two things is more specialized. */
16166 if (arg == parm && !uses_template_parms (parm))
16167 return unify_success (explain_p);
16169 /* Handle init lists early, so the rest of the function can assume
16170 we're dealing with a type. */
16171 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
16175 tree orig_parm = parm;
16177 /* Replace T with std::initializer_list<T> for deduction. */
16178 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16179 && flag_deduce_init_list)
16180 parm = listify (parm);
16182 if (!is_std_init_list (parm))
16183 /* We can only deduce from an initializer list argument if the
16184 parameter is std::initializer_list; otherwise this is a
16185 non-deduced context. */
16186 return unify_success (explain_p);
16188 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
16190 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
16192 int elt_strict = strict;
16194 if (elt == error_mark_node)
16195 return unify_invalid (explain_p);
16197 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
16199 tree type = TREE_TYPE (elt);
16200 /* It should only be possible to get here for a call. */
16201 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
16202 elt_strict |= maybe_adjust_types_for_deduction
16203 (DEDUCE_CALL, &elttype, &type, elt);
16207 RECUR_AND_CHECK_FAILURE (tparms, targs, elttype, elt, elt_strict,
16211 /* If the std::initializer_list<T> deduction worked, replace the
16212 deduced A with std::initializer_list<A>. */
16213 if (orig_parm != parm)
16215 idx = TEMPLATE_TYPE_IDX (orig_parm);
16216 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16217 targ = listify (targ);
16218 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
16220 return unify_success (explain_p);
16223 /* Immediately reject some pairs that won't unify because of
16224 cv-qualification mismatches. */
16225 if (TREE_CODE (arg) == TREE_CODE (parm)
16227 /* It is the elements of the array which hold the cv quals of an array
16228 type, and the elements might be template type parms. We'll check
16229 when we recurse. */
16230 && TREE_CODE (arg) != ARRAY_TYPE
16231 /* We check the cv-qualifiers when unifying with template type
16232 parameters below. We want to allow ARG `const T' to unify with
16233 PARM `T' for example, when computing which of two templates
16234 is more specialized, for example. */
16235 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
16236 && !check_cv_quals_for_unify (strict_in, arg, parm))
16237 return unify_cv_qual_mismatch (explain_p, parm, arg);
16239 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
16240 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
16241 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
16242 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
16243 strict &= ~UNIFY_ALLOW_DERIVED;
16244 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
16245 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
16247 switch (TREE_CODE (parm))
16249 case TYPENAME_TYPE:
16251 case UNBOUND_CLASS_TEMPLATE:
16252 /* In a type which contains a nested-name-specifier, template
16253 argument values cannot be deduced for template parameters used
16254 within the nested-name-specifier. */
16255 return unify_success (explain_p);
16257 case TEMPLATE_TYPE_PARM:
16258 case TEMPLATE_TEMPLATE_PARM:
16259 case BOUND_TEMPLATE_TEMPLATE_PARM:
16260 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16261 if (tparm == error_mark_node)
16262 return unify_invalid (explain_p);
16264 if (TEMPLATE_TYPE_LEVEL (parm)
16265 != template_decl_level (tparm))
16266 /* The PARM is not one we're trying to unify. Just check
16267 to see if it matches ARG. */
16269 if (TREE_CODE (arg) == TREE_CODE (parm)
16270 && same_type_p (parm, arg))
16271 return unify_success (explain_p);
16273 return unify_type_mismatch (explain_p, parm, arg);
16275 idx = TEMPLATE_TYPE_IDX (parm);
16276 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16277 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
16278 if (tparm == error_mark_node)
16279 return unify_invalid (explain_p);
16281 /* Check for mixed types and values. */
16282 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16283 && TREE_CODE (tparm) != TYPE_DECL)
16284 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16285 && TREE_CODE (tparm) != TEMPLATE_DECL))
16286 gcc_unreachable ();
16288 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16290 /* ARG must be constructed from a template class or a template
16291 template parameter. */
16292 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
16293 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
16294 return unify_template_deduction_failure (explain_p, parm, arg);
16297 tree parmvec = TYPE_TI_ARGS (parm);
16298 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
16299 tree full_argvec = add_to_template_args (targs, argvec);
16301 = DECL_INNERMOST_TEMPLATE_PARMS
16302 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
16304 int parm_variadic_p = 0;
16306 /* The resolution to DR150 makes clear that default
16307 arguments for an N-argument may not be used to bind T
16308 to a template template parameter with fewer than N
16309 parameters. It is not safe to permit the binding of
16310 default arguments as an extension, as that may change
16311 the meaning of a conforming program. Consider:
16313 struct Dense { static const unsigned int dim = 1; };
16315 template <template <typename> class View,
16317 void operator+(float, View<Block> const&);
16319 template <typename Block,
16320 unsigned int Dim = Block::dim>
16321 struct Lvalue_proxy { operator float() const; };
16325 Lvalue_proxy<Dense> p;
16330 Here, if Lvalue_proxy is permitted to bind to View, then
16331 the global operator+ will be used; if they are not, the
16332 Lvalue_proxy will be converted to float. */
16333 if (coerce_template_parms (parm_parms,
16335 TYPE_TI_TEMPLATE (parm),
16337 ? tf_warning_or_error
16339 /*require_all_args=*/true,
16340 /*use_default_args=*/false)
16341 == error_mark_node)
16344 /* Deduce arguments T, i from TT<T> or TT<i>.
16345 We check each element of PARMVEC and ARGVEC individually
16346 rather than the whole TREE_VEC since they can have
16347 different number of elements. */
16349 parmvec = expand_template_argument_pack (parmvec);
16350 argvec = expand_template_argument_pack (argvec);
16352 len = TREE_VEC_LENGTH (parmvec);
16354 /* Check if the parameters end in a pack, making them
16357 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
16358 parm_variadic_p = 1;
16360 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
16361 return unify_too_few_arguments (explain_p,
16362 TREE_VEC_LENGTH (argvec), len);
16364 for (i = 0; i < len - parm_variadic_p; ++i)
16366 RECUR_AND_CHECK_FAILURE (tparms, targs,
16367 TREE_VEC_ELT (parmvec, i),
16368 TREE_VEC_ELT (argvec, i),
16369 UNIFY_ALLOW_NONE, explain_p);
16372 if (parm_variadic_p
16373 && unify_pack_expansion (tparms, targs,
16376 /*subr=*/true, explain_p))
16379 arg = TYPE_TI_TEMPLATE (arg);
16381 /* Fall through to deduce template name. */
16384 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16385 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16387 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
16389 /* Simple cases: Value already set, does match or doesn't. */
16390 if (targ != NULL_TREE && template_args_equal (targ, arg))
16391 return unify_success (explain_p);
16393 return unify_inconsistency (explain_p, parm, targ, arg);
16397 /* If PARM is `const T' and ARG is only `int', we don't have
16398 a match unless we are allowing additional qualification.
16399 If ARG is `const int' and PARM is just `T' that's OK;
16400 that binds `const int' to `T'. */
16401 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
16403 return unify_cv_qual_mismatch (explain_p, parm, arg);
16405 /* Consider the case where ARG is `const volatile int' and
16406 PARM is `const T'. Then, T should be `volatile int'. */
16407 arg = cp_build_qualified_type_real
16408 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
16409 if (arg == error_mark_node)
16410 return unify_invalid (explain_p);
16412 /* Simple cases: Value already set, does match or doesn't. */
16413 if (targ != NULL_TREE && same_type_p (targ, arg))
16414 return unify_success (explain_p);
16416 return unify_inconsistency (explain_p, parm, targ, arg);
16418 /* Make sure that ARG is not a variable-sized array. (Note
16419 that were talking about variable-sized arrays (like
16420 `int[n]'), rather than arrays of unknown size (like
16421 `int[]').) We'll get very confused by such a type since
16422 the bound of the array is not constant, and therefore
16423 not mangleable. Besides, such types are not allowed in
16424 ISO C++, so we can do as we please here. We do allow
16425 them for 'auto' deduction, since that isn't ABI-exposed. */
16426 if (!is_auto (parm) && variably_modified_type_p (arg, NULL_TREE))
16427 return unify_vla_arg (explain_p, arg);
16429 /* Strip typedefs as in convert_template_argument. */
16430 arg = canonicalize_type_argument (arg, tf_none);
16433 /* If ARG is a parameter pack or an expansion, we cannot unify
16434 against it unless PARM is also a parameter pack. */
16435 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16436 && !template_parameter_pack_p (parm))
16437 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16439 /* If the argument deduction results is a METHOD_TYPE,
16440 then there is a problem.
16441 METHOD_TYPE doesn't map to any real C++ type the result of
16442 the deduction can not be of that type. */
16443 if (TREE_CODE (arg) == METHOD_TYPE)
16444 return unify_method_type_error (explain_p, arg);
16446 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16447 return unify_success (explain_p);
16449 case TEMPLATE_PARM_INDEX:
16450 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16451 if (tparm == error_mark_node)
16452 return unify_invalid (explain_p);
16454 if (TEMPLATE_PARM_LEVEL (parm)
16455 != template_decl_level (tparm))
16457 /* The PARM is not one we're trying to unify. Just check
16458 to see if it matches ARG. */
16459 int result = !(TREE_CODE (arg) == TREE_CODE (parm)
16460 && cp_tree_equal (parm, arg));
16462 unify_expression_unequal (explain_p, parm, arg);
16466 idx = TEMPLATE_PARM_IDX (parm);
16467 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16471 int x = !cp_tree_equal (targ, arg);
16473 unify_inconsistency (explain_p, parm, targ, arg);
16477 /* [temp.deduct.type] If, in the declaration of a function template
16478 with a non-type template-parameter, the non-type
16479 template-parameter is used in an expression in the function
16480 parameter-list and, if the corresponding template-argument is
16481 deduced, the template-argument type shall match the type of the
16482 template-parameter exactly, except that a template-argument
16483 deduced from an array bound may be of any integral type.
16484 The non-type parameter might use already deduced type parameters. */
16485 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
16486 if (!TREE_TYPE (arg))
16487 /* Template-parameter dependent expression. Just accept it for now.
16488 It will later be processed in convert_template_argument. */
16490 else if (same_type_p (TREE_TYPE (arg), tparm))
16492 else if ((strict & UNIFY_ALLOW_INTEGER)
16493 && (TREE_CODE (tparm) == INTEGER_TYPE
16494 || TREE_CODE (tparm) == BOOLEAN_TYPE))
16495 /* Convert the ARG to the type of PARM; the deduced non-type
16496 template argument must exactly match the types of the
16497 corresponding parameter. */
16498 arg = fold (build_nop (tparm, arg));
16499 else if (uses_template_parms (tparm))
16500 /* We haven't deduced the type of this parameter yet. Try again
16502 return unify_success (explain_p);
16504 return unify_type_mismatch (explain_p, tparm, arg);
16506 /* If ARG is a parameter pack or an expansion, we cannot unify
16507 against it unless PARM is also a parameter pack. */
16508 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16509 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
16510 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16512 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16513 return unify_success (explain_p);
16517 /* A pointer-to-member constant can be unified only with
16518 another constant. */
16519 if (TREE_CODE (arg) != PTRMEM_CST)
16520 return unify_ptrmem_cst_mismatch (explain_p, parm, arg);
16522 /* Just unify the class member. It would be useless (and possibly
16523 wrong, depending on the strict flags) to unify also
16524 PTRMEM_CST_CLASS, because we want to be sure that both parm and
16525 arg refer to the same variable, even if through different
16526 classes. For instance:
16528 struct A { int x; };
16531 Unification of &A::x and &B::x must succeed. */
16532 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
16533 PTRMEM_CST_MEMBER (arg), strict, explain_p);
16538 if (TREE_CODE (arg) != POINTER_TYPE)
16539 return unify_type_mismatch (explain_p, parm, arg);
16541 /* [temp.deduct.call]
16543 A can be another pointer or pointer to member type that can
16544 be converted to the deduced A via a qualification
16545 conversion (_conv.qual_).
16547 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
16548 This will allow for additional cv-qualification of the
16549 pointed-to types if appropriate. */
16551 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
16552 /* The derived-to-base conversion only persists through one
16553 level of pointers. */
16554 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
16556 return unify (tparms, targs, TREE_TYPE (parm),
16557 TREE_TYPE (arg), strict, explain_p);
16560 case REFERENCE_TYPE:
16561 if (TREE_CODE (arg) != REFERENCE_TYPE)
16562 return unify_type_mismatch (explain_p, parm, arg);
16563 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16564 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16567 if (TREE_CODE (arg) != ARRAY_TYPE)
16568 return unify_type_mismatch (explain_p, parm, arg);
16569 if ((TYPE_DOMAIN (parm) == NULL_TREE)
16570 != (TYPE_DOMAIN (arg) == NULL_TREE))
16571 return unify_type_mismatch (explain_p, parm, arg);
16572 if (TYPE_DOMAIN (parm) != NULL_TREE)
16579 /* Our representation of array types uses "N - 1" as the
16580 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
16581 not an integer constant. We cannot unify arbitrarily
16582 complex expressions, so we eliminate the MINUS_EXPRs
16584 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
16585 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
16588 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
16589 parm_max = TREE_OPERAND (parm_max, 0);
16591 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
16592 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
16595 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
16596 trying to unify the type of a variable with the type
16597 of a template parameter. For example:
16599 template <unsigned int N>
16600 void f (char (&) [N]);
16607 Here, the type of the ARG will be "int [g(i)]", and
16608 may be a SAVE_EXPR, etc. */
16609 if (TREE_CODE (arg_max) != MINUS_EXPR)
16610 return unify_vla_arg (explain_p, arg);
16611 arg_max = TREE_OPERAND (arg_max, 0);
16614 /* If only one of the bounds used a MINUS_EXPR, compensate
16615 by adding one to the other bound. */
16616 if (parm_cst && !arg_cst)
16617 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
16621 else if (arg_cst && !parm_cst)
16622 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
16627 RECUR_AND_CHECK_FAILURE (tparms, targs, parm_max, arg_max,
16628 UNIFY_ALLOW_INTEGER, explain_p);
16630 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16631 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16638 case ENUMERAL_TYPE:
16641 if (TREE_CODE (arg) != TREE_CODE (parm))
16642 return unify_type_mismatch (explain_p, parm, arg);
16644 /* We have already checked cv-qualification at the top of the
16646 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
16647 return unify_type_mismatch (explain_p, parm, arg);
16649 /* As far as unification is concerned, this wins. Later checks
16650 will invalidate it if necessary. */
16651 return unify_success (explain_p);
16653 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
16654 /* Type INTEGER_CST can come from ordinary constant template args. */
16656 while (TREE_CODE (arg) == NOP_EXPR)
16657 arg = TREE_OPERAND (arg, 0);
16659 if (TREE_CODE (arg) != INTEGER_CST)
16660 return unify_template_argument_mismatch (explain_p, parm, arg);
16661 return (tree_int_cst_equal (parm, arg)
16662 ? unify_success (explain_p)
16663 : unify_template_argument_mismatch (explain_p, parm, arg));
16667 int i, len, argslen;
16668 int parm_variadic_p = 0;
16670 if (TREE_CODE (arg) != TREE_VEC)
16671 return unify_template_argument_mismatch (explain_p, parm, arg);
16673 len = TREE_VEC_LENGTH (parm);
16674 argslen = TREE_VEC_LENGTH (arg);
16676 /* Check for pack expansions in the parameters. */
16677 for (i = 0; i < len; ++i)
16679 if (PACK_EXPANSION_P (TREE_VEC_ELT (parm, i)))
16682 /* We can unify against something with a trailing
16684 parm_variadic_p = 1;
16686 /* [temp.deduct.type]/9: If the template argument list of
16687 P contains a pack expansion that is not the last
16688 template argument, the entire template argument list
16689 is a non-deduced context. */
16690 return unify_success (explain_p);
16694 /* If we don't have enough arguments to satisfy the parameters
16695 (not counting the pack expression at the end), or we have
16696 too many arguments for a parameter list that doesn't end in
16697 a pack expression, we can't unify. */
16698 if (parm_variadic_p
16699 ? argslen < len - parm_variadic_p
16701 return unify_arity (explain_p, TREE_VEC_LENGTH (arg), len);
16703 /* Unify all of the parameters that precede the (optional)
16704 pack expression. */
16705 for (i = 0; i < len - parm_variadic_p; ++i)
16707 RECUR_AND_CHECK_FAILURE (tparms, targs,
16708 TREE_VEC_ELT (parm, i),
16709 TREE_VEC_ELT (arg, i),
16710 UNIFY_ALLOW_NONE, explain_p);
16712 if (parm_variadic_p)
16713 return unify_pack_expansion (tparms, targs, parm, arg,
16715 /*subr=*/true, explain_p);
16716 return unify_success (explain_p);
16721 if (TREE_CODE (arg) != TREE_CODE (parm))
16722 return unify_type_mismatch (explain_p, parm, arg);
16724 if (TYPE_PTRMEMFUNC_P (parm))
16726 if (!TYPE_PTRMEMFUNC_P (arg))
16727 return unify_type_mismatch (explain_p, parm, arg);
16729 return unify (tparms, targs,
16730 TYPE_PTRMEMFUNC_FN_TYPE (parm),
16731 TYPE_PTRMEMFUNC_FN_TYPE (arg),
16732 strict, explain_p);
16735 if (CLASSTYPE_TEMPLATE_INFO (parm))
16737 tree t = NULL_TREE;
16739 if (strict_in & UNIFY_ALLOW_DERIVED)
16741 /* First, we try to unify the PARM and ARG directly. */
16742 t = try_class_unification (tparms, targs,
16743 parm, arg, explain_p);
16747 /* Fallback to the special case allowed in
16748 [temp.deduct.call]:
16750 If P is a class, and P has the form
16751 template-id, then A can be a derived class of
16752 the deduced A. Likewise, if P is a pointer to
16753 a class of the form template-id, A can be a
16754 pointer to a derived class pointed to by the
16756 enum template_base_result r;
16757 r = get_template_base (tparms, targs, parm, arg,
16761 return unify_no_common_base (explain_p, r, parm, arg);
16764 else if (CLASSTYPE_TEMPLATE_INFO (arg)
16765 && (CLASSTYPE_TI_TEMPLATE (parm)
16766 == CLASSTYPE_TI_TEMPLATE (arg)))
16767 /* Perhaps PARM is something like S<U> and ARG is S<int>.
16768 Then, we should unify `int' and `U'. */
16771 /* There's no chance of unification succeeding. */
16772 return unify_type_mismatch (explain_p, parm, arg);
16774 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
16775 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE, explain_p);
16777 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
16778 return unify_type_mismatch (explain_p, parm, arg);
16779 return unify_success (explain_p);
16782 case FUNCTION_TYPE:
16784 unsigned int nargs;
16789 if (TREE_CODE (arg) != TREE_CODE (parm))
16790 return unify_type_mismatch (explain_p, parm, arg);
16792 /* CV qualifications for methods can never be deduced, they must
16793 match exactly. We need to check them explicitly here,
16794 because type_unification_real treats them as any other
16795 cv-qualified parameter. */
16796 if (TREE_CODE (parm) == METHOD_TYPE
16797 && (!check_cv_quals_for_unify
16799 class_of_this_parm (arg),
16800 class_of_this_parm (parm))))
16801 return unify_cv_qual_mismatch (explain_p, parm, arg);
16803 RECUR_AND_CHECK_FAILURE (tparms, targs, TREE_TYPE (parm),
16804 TREE_TYPE (arg), UNIFY_ALLOW_NONE, explain_p);
16806 nargs = list_length (TYPE_ARG_TYPES (arg));
16807 args = XALLOCAVEC (tree, nargs);
16808 for (a = TYPE_ARG_TYPES (arg), i = 0;
16809 a != NULL_TREE && a != void_list_node;
16810 a = TREE_CHAIN (a), ++i)
16811 args[i] = TREE_VALUE (a);
16814 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
16815 args, nargs, 1, DEDUCE_EXACT,
16816 LOOKUP_NORMAL, explain_p);
16820 /* Unify a pointer to member with a pointer to member function, which
16821 deduces the type of the member as a function type. */
16822 if (TYPE_PTRMEMFUNC_P (arg))
16827 /* Check top-level cv qualifiers */
16828 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
16829 return unify_cv_qual_mismatch (explain_p, parm, arg);
16831 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16832 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg),
16833 UNIFY_ALLOW_NONE, explain_p);
16835 /* Determine the type of the function we are unifying against. */
16836 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
16838 build_function_type (TREE_TYPE (method_type),
16839 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
16841 /* Extract the cv-qualifiers of the member function from the
16842 implicit object parameter and place them on the function
16843 type to be restored later. */
16844 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
16845 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict, explain_p);
16848 if (TREE_CODE (arg) != OFFSET_TYPE)
16849 return unify_type_mismatch (explain_p, parm, arg);
16850 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16851 TYPE_OFFSET_BASETYPE (arg),
16852 UNIFY_ALLOW_NONE, explain_p);
16853 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16854 strict, explain_p);
16857 if (DECL_TEMPLATE_PARM_P (parm))
16858 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict, explain_p);
16859 if (arg != integral_constant_value (parm))
16860 return unify_template_argument_mismatch (explain_p, parm, arg);
16861 return unify_success (explain_p);
16864 case TEMPLATE_DECL:
16865 /* Matched cases are handled by the ARG == PARM test above. */
16866 return unify_template_argument_mismatch (explain_p, parm, arg);
16869 /* A non-type template parameter that is a variable should be a
16870 an integral constant, in which case, it whould have been
16871 folded into its (constant) value. So we should not be getting
16872 a variable here. */
16873 gcc_unreachable ();
16875 case TYPE_ARGUMENT_PACK:
16876 case NONTYPE_ARGUMENT_PACK:
16877 return unify (tparms, targs, ARGUMENT_PACK_ARGS (parm),
16878 ARGUMENT_PACK_ARGS (arg), strict, explain_p);
16881 case DECLTYPE_TYPE:
16882 case UNDERLYING_TYPE:
16883 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
16884 or UNDERLYING_TYPE nodes. */
16885 return unify_success (explain_p);
16888 /* Unification fails if we hit an error node. */
16889 return unify_invalid (explain_p);
16892 /* An unresolved overload is a nondeduced context. */
16893 if (is_overloaded_fn (parm) || type_unknown_p (parm))
16894 return unify_success (explain_p);
16895 gcc_assert (EXPR_P (parm));
16897 /* We must be looking at an expression. This can happen with
16901 void foo(S<I>, S<I + 2>);
16903 This is a "nondeduced context":
16907 The nondeduced contexts are:
16909 --A type that is a template-id in which one or more of
16910 the template-arguments is an expression that references
16911 a template-parameter.
16913 In these cases, we assume deduction succeeded, but don't
16914 actually infer any unifications. */
16916 if (!uses_template_parms (parm)
16917 && !template_args_equal (parm, arg))
16918 return unify_expression_unequal (explain_p, parm, arg);
16920 return unify_success (explain_p);
16923 #undef RECUR_AND_CHECK_FAILURE
16925 /* Note that DECL can be defined in this translation unit, if
16929 mark_definable (tree decl)
16932 DECL_NOT_REALLY_EXTERN (decl) = 1;
16933 FOR_EACH_CLONE (clone, decl)
16934 DECL_NOT_REALLY_EXTERN (clone) = 1;
16937 /* Called if RESULT is explicitly instantiated, or is a member of an
16938 explicitly instantiated class. */
16941 mark_decl_instantiated (tree result, int extern_p)
16943 SET_DECL_EXPLICIT_INSTANTIATION (result);
16945 /* If this entity has already been written out, it's too late to
16946 make any modifications. */
16947 if (TREE_ASM_WRITTEN (result))
16950 if (TREE_CODE (result) != FUNCTION_DECL)
16951 /* The TREE_PUBLIC flag for function declarations will have been
16952 set correctly by tsubst. */
16953 TREE_PUBLIC (result) = 1;
16955 /* This might have been set by an earlier implicit instantiation. */
16956 DECL_COMDAT (result) = 0;
16959 DECL_NOT_REALLY_EXTERN (result) = 0;
16962 mark_definable (result);
16963 /* Always make artificials weak. */
16964 if (DECL_ARTIFICIAL (result) && flag_weak)
16965 comdat_linkage (result);
16966 /* For WIN32 we also want to put explicit instantiations in
16967 linkonce sections. */
16968 else if (TREE_PUBLIC (result))
16969 maybe_make_one_only (result);
16972 /* If EXTERN_P, then this function will not be emitted -- unless
16973 followed by an explicit instantiation, at which point its linkage
16974 will be adjusted. If !EXTERN_P, then this function will be
16975 emitted here. In neither circumstance do we want
16976 import_export_decl to adjust the linkage. */
16977 DECL_INTERFACE_KNOWN (result) = 1;
16980 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
16981 important template arguments. If any are missing, we check whether
16982 they're important by using error_mark_node for substituting into any
16983 args that were used for partial ordering (the ones between ARGS and END)
16984 and seeing if it bubbles up. */
16987 check_undeduced_parms (tree targs, tree args, tree end)
16989 bool found = false;
16991 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
16992 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
16995 TREE_VEC_ELT (targs, i) = error_mark_node;
16999 for (; args != end; args = TREE_CHAIN (args))
17001 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
17002 if (substed == error_mark_node)
17009 /* Given two function templates PAT1 and PAT2, return:
17011 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
17012 -1 if PAT2 is more specialized than PAT1.
17013 0 if neither is more specialized.
17015 LEN indicates the number of parameters we should consider
17016 (defaulted parameters should not be considered).
17018 The 1998 std underspecified function template partial ordering, and
17019 DR214 addresses the issue. We take pairs of arguments, one from
17020 each of the templates, and deduce them against each other. One of
17021 the templates will be more specialized if all the *other*
17022 template's arguments deduce against its arguments and at least one
17023 of its arguments *does* *not* deduce against the other template's
17024 corresponding argument. Deduction is done as for class templates.
17025 The arguments used in deduction have reference and top level cv
17026 qualifiers removed. Iff both arguments were originally reference
17027 types *and* deduction succeeds in both directions, the template
17028 with the more cv-qualified argument wins for that pairing (if
17029 neither is more cv-qualified, they both are equal). Unlike regular
17030 deduction, after all the arguments have been deduced in this way,
17031 we do *not* verify the deduced template argument values can be
17032 substituted into non-deduced contexts.
17034 The logic can be a bit confusing here, because we look at deduce1 and
17035 targs1 to see if pat2 is at least as specialized, and vice versa; if we
17036 can find template arguments for pat1 to make arg1 look like arg2, that
17037 means that arg2 is at least as specialized as arg1. */
17040 more_specialized_fn (tree pat1, tree pat2, int len)
17042 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
17043 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
17044 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
17045 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
17046 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
17047 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
17048 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
17049 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
17050 tree origs1, origs2;
17051 bool lose1 = false;
17052 bool lose2 = false;
17054 /* Remove the this parameter from non-static member functions. If
17055 one is a non-static member function and the other is not a static
17056 member function, remove the first parameter from that function
17057 also. This situation occurs for operator functions where we
17058 locate both a member function (with this pointer) and non-member
17059 operator (with explicit first operand). */
17060 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
17062 len--; /* LEN is the number of significant arguments for DECL1 */
17063 args1 = TREE_CHAIN (args1);
17064 if (!DECL_STATIC_FUNCTION_P (decl2))
17065 args2 = TREE_CHAIN (args2);
17067 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
17069 args2 = TREE_CHAIN (args2);
17070 if (!DECL_STATIC_FUNCTION_P (decl1))
17073 args1 = TREE_CHAIN (args1);
17077 /* If only one is a conversion operator, they are unordered. */
17078 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
17081 /* Consider the return type for a conversion function */
17082 if (DECL_CONV_FN_P (decl1))
17084 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
17085 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
17089 processing_template_decl++;
17095 /* Stop when an ellipsis is seen. */
17096 && args1 != NULL_TREE && args2 != NULL_TREE)
17098 tree arg1 = TREE_VALUE (args1);
17099 tree arg2 = TREE_VALUE (args2);
17100 int deduce1, deduce2;
17104 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17105 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17107 /* When both arguments are pack expansions, we need only
17108 unify the patterns themselves. */
17109 arg1 = PACK_EXPANSION_PATTERN (arg1);
17110 arg2 = PACK_EXPANSION_PATTERN (arg2);
17112 /* This is the last comparison we need to do. */
17116 if (TREE_CODE (arg1) == REFERENCE_TYPE)
17118 arg1 = TREE_TYPE (arg1);
17119 quals1 = cp_type_quals (arg1);
17122 if (TREE_CODE (arg2) == REFERENCE_TYPE)
17124 arg2 = TREE_TYPE (arg2);
17125 quals2 = cp_type_quals (arg2);
17128 if ((quals1 < 0) != (quals2 < 0))
17130 /* Only of the args is a reference, see if we should apply
17131 array/function pointer decay to it. This is not part of
17132 DR214, but is, IMHO, consistent with the deduction rules
17133 for the function call itself, and with our earlier
17134 implementation of the underspecified partial ordering
17135 rules. (nathan). */
17138 switch (TREE_CODE (arg1))
17141 arg1 = TREE_TYPE (arg1);
17143 case FUNCTION_TYPE:
17144 arg1 = build_pointer_type (arg1);
17153 switch (TREE_CODE (arg2))
17156 arg2 = TREE_TYPE (arg2);
17158 case FUNCTION_TYPE:
17159 arg2 = build_pointer_type (arg2);
17168 arg1 = TYPE_MAIN_VARIANT (arg1);
17169 arg2 = TYPE_MAIN_VARIANT (arg2);
17171 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
17173 int i, len2 = list_length (args2);
17174 tree parmvec = make_tree_vec (1);
17175 tree argvec = make_tree_vec (len2);
17178 /* Setup the parameter vector, which contains only ARG1. */
17179 TREE_VEC_ELT (parmvec, 0) = arg1;
17181 /* Setup the argument vector, which contains the remaining
17183 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
17184 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17186 deduce1 = (unify_pack_expansion (tparms1, targs1, parmvec,
17187 argvec, DEDUCE_EXACT,
17188 /*subr=*/true, /*explain_p=*/false)
17191 /* We cannot deduce in the other direction, because ARG1 is
17192 a pack expansion but ARG2 is not. */
17195 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17197 int i, len1 = list_length (args1);
17198 tree parmvec = make_tree_vec (1);
17199 tree argvec = make_tree_vec (len1);
17202 /* Setup the parameter vector, which contains only ARG1. */
17203 TREE_VEC_ELT (parmvec, 0) = arg2;
17205 /* Setup the argument vector, which contains the remaining
17207 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
17208 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17210 deduce2 = (unify_pack_expansion (tparms2, targs2, parmvec,
17211 argvec, DEDUCE_EXACT,
17212 /*subr=*/true, /*explain_p=*/false)
17215 /* We cannot deduce in the other direction, because ARG2 is
17216 a pack expansion but ARG1 is not.*/
17222 /* The normal case, where neither argument is a pack
17224 deduce1 = (unify (tparms1, targs1, arg1, arg2,
17225 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17227 deduce2 = (unify (tparms2, targs2, arg2, arg1,
17228 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17232 /* If we couldn't deduce arguments for tparms1 to make arg1 match
17233 arg2, then arg2 is not as specialized as arg1. */
17239 /* "If, for a given type, deduction succeeds in both directions
17240 (i.e., the types are identical after the transformations above)
17241 and if the type from the argument template is more cv-qualified
17242 than the type from the parameter template (as described above)
17243 that type is considered to be more specialized than the other. If
17244 neither type is more cv-qualified than the other then neither type
17245 is more specialized than the other." */
17247 if (deduce1 && deduce2
17248 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
17250 if ((quals1 & quals2) == quals2)
17252 if ((quals1 & quals2) == quals1)
17256 if (lose1 && lose2)
17257 /* We've failed to deduce something in either direction.
17258 These must be unordered. */
17261 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17262 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17263 /* We have already processed all of the arguments in our
17264 handing of the pack expansion type. */
17267 args1 = TREE_CHAIN (args1);
17268 args2 = TREE_CHAIN (args2);
17271 /* "In most cases, all template parameters must have values in order for
17272 deduction to succeed, but for partial ordering purposes a template
17273 parameter may remain without a value provided it is not used in the
17274 types being used for partial ordering."
17276 Thus, if we are missing any of the targs1 we need to substitute into
17277 origs1, then pat2 is not as specialized as pat1. This can happen when
17278 there is a nondeduced context. */
17279 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
17281 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
17284 processing_template_decl--;
17286 /* All things being equal, if the next argument is a pack expansion
17287 for one function but not for the other, prefer the
17288 non-variadic function. FIXME this is bogus; see c++/41958. */
17290 && args1 && TREE_VALUE (args1)
17291 && args2 && TREE_VALUE (args2))
17293 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
17294 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
17297 if (lose1 == lose2)
17305 /* Determine which of two partial specializations is more specialized.
17307 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
17308 to the first partial specialization. The TREE_VALUE is the
17309 innermost set of template parameters for the partial
17310 specialization. PAT2 is similar, but for the second template.
17312 Return 1 if the first partial specialization is more specialized;
17313 -1 if the second is more specialized; 0 if neither is more
17316 See [temp.class.order] for information about determining which of
17317 two templates is more specialized. */
17320 more_specialized_class (tree pat1, tree pat2)
17325 bool any_deductions = false;
17327 tmpl1 = TREE_TYPE (pat1);
17328 tmpl2 = TREE_TYPE (pat2);
17330 /* Just like what happens for functions, if we are ordering between
17331 different class template specializations, we may encounter dependent
17332 types in the arguments, and we need our dependency check functions
17333 to behave correctly. */
17334 ++processing_template_decl;
17335 targs = get_class_bindings (TREE_VALUE (pat1),
17336 CLASSTYPE_TI_ARGS (tmpl1),
17337 CLASSTYPE_TI_ARGS (tmpl2));
17341 any_deductions = true;
17344 targs = get_class_bindings (TREE_VALUE (pat2),
17345 CLASSTYPE_TI_ARGS (tmpl2),
17346 CLASSTYPE_TI_ARGS (tmpl1));
17350 any_deductions = true;
17352 --processing_template_decl;
17354 /* In the case of a tie where at least one of the class templates
17355 has a parameter pack at the end, the template with the most
17356 non-packed parameters wins. */
17359 && (template_args_variadic_p (TREE_PURPOSE (pat1))
17360 || template_args_variadic_p (TREE_PURPOSE (pat2))))
17362 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
17363 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
17364 int len1 = TREE_VEC_LENGTH (args1);
17365 int len2 = TREE_VEC_LENGTH (args2);
17367 /* We don't count the pack expansion at the end. */
17368 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
17370 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
17375 else if (len1 < len2)
17382 /* Return the template arguments that will produce the function signature
17383 DECL from the function template FN, with the explicit template
17384 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
17385 also match. Return NULL_TREE if no satisfactory arguments could be
17389 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
17391 int ntparms = DECL_NTPARMS (fn);
17392 tree targs = make_tree_vec (ntparms);
17394 tree decl_arg_types;
17396 unsigned int nargs, ix;
17399 /* Substitute the explicit template arguments into the type of DECL.
17400 The call to fn_type_unification will handle substitution into the
17402 decl_type = TREE_TYPE (decl);
17403 if (explicit_args && uses_template_parms (decl_type))
17406 tree converted_args;
17408 if (DECL_TEMPLATE_INFO (decl))
17409 tmpl = DECL_TI_TEMPLATE (decl);
17411 /* We can get here for some invalid specializations. */
17415 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17416 explicit_args, NULL_TREE,
17418 /*require_all_args=*/false,
17419 /*use_default_args=*/false);
17420 if (converted_args == error_mark_node)
17423 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
17424 if (decl_type == error_mark_node)
17428 /* Never do unification on the 'this' parameter. */
17429 decl_arg_types = skip_artificial_parms_for (decl,
17430 TYPE_ARG_TYPES (decl_type));
17432 nargs = list_length (decl_arg_types);
17433 args = XALLOCAVEC (tree, nargs);
17434 for (arg = decl_arg_types, ix = 0;
17435 arg != NULL_TREE && arg != void_list_node;
17436 arg = TREE_CHAIN (arg), ++ix)
17437 args[ix] = TREE_VALUE (arg);
17439 if (fn_type_unification (fn, explicit_args, targs,
17441 (check_rettype || DECL_CONV_FN_P (fn)
17442 ? TREE_TYPE (decl_type) : NULL_TREE),
17443 DEDUCE_EXACT, LOOKUP_NORMAL, /*explain_p=*/false))
17449 /* Return the innermost template arguments that, when applied to a
17450 template specialization whose innermost template parameters are
17451 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
17454 For example, suppose we have:
17456 template <class T, class U> struct S {};
17457 template <class T> struct S<T*, int> {};
17459 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
17460 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
17461 int}. The resulting vector will be {double}, indicating that `T'
17462 is bound to `double'. */
17465 get_class_bindings (tree tparms, tree spec_args, tree args)
17467 int i, ntparms = TREE_VEC_LENGTH (tparms);
17469 tree innermost_deduced_args;
17471 innermost_deduced_args = make_tree_vec (ntparms);
17472 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17474 deduced_args = copy_node (args);
17475 SET_TMPL_ARGS_LEVEL (deduced_args,
17476 TMPL_ARGS_DEPTH (deduced_args),
17477 innermost_deduced_args);
17480 deduced_args = innermost_deduced_args;
17482 if (unify (tparms, deduced_args,
17483 INNERMOST_TEMPLATE_ARGS (spec_args),
17484 INNERMOST_TEMPLATE_ARGS (args),
17485 UNIFY_ALLOW_NONE, /*explain_p=*/false))
17488 for (i = 0; i < ntparms; ++i)
17489 if (! TREE_VEC_ELT (innermost_deduced_args, i))
17492 /* Verify that nondeduced template arguments agree with the type
17493 obtained from argument deduction.
17497 struct A { typedef int X; };
17498 template <class T, class U> struct C {};
17499 template <class T> struct C<T, typename T::X> {};
17501 Then with the instantiation `C<A, int>', we can deduce that
17502 `T' is `A' but unify () does not check whether `typename T::X'
17504 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
17505 if (spec_args == error_mark_node
17506 /* We only need to check the innermost arguments; the other
17507 arguments will always agree. */
17508 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
17509 INNERMOST_TEMPLATE_ARGS (args)))
17512 /* Now that we have bindings for all of the template arguments,
17513 ensure that the arguments deduced for the template template
17514 parameters have compatible template parameter lists. See the use
17515 of template_template_parm_bindings_ok_p in fn_type_unification
17516 for more information. */
17517 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
17520 return deduced_args;
17523 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
17524 Return the TREE_LIST node with the most specialized template, if
17525 any. If there is no most specialized template, the error_mark_node
17528 Note that this function does not look at, or modify, the
17529 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
17530 returned is one of the elements of INSTANTIATIONS, callers may
17531 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
17532 and retrieve it from the value returned. */
17535 most_specialized_instantiation (tree templates)
17539 ++processing_template_decl;
17542 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
17546 if (get_bindings (TREE_VALUE (champ),
17547 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17548 NULL_TREE, /*check_ret=*/true))
17551 if (get_bindings (TREE_VALUE (fn),
17552 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17553 NULL_TREE, /*check_ret=*/true))
17560 /* Equally specialized, move to next function. If there
17561 is no next function, nothing's most specialized. */
17562 fn = TREE_CHAIN (fn);
17570 /* Now verify that champ is better than everything earlier in the
17571 instantiation list. */
17572 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
17573 if (get_bindings (TREE_VALUE (champ),
17574 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17575 NULL_TREE, /*check_ret=*/true)
17576 || !get_bindings (TREE_VALUE (fn),
17577 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17578 NULL_TREE, /*check_ret=*/true))
17584 processing_template_decl--;
17587 return error_mark_node;
17592 /* If DECL is a specialization of some template, return the most
17593 general such template. Otherwise, returns NULL_TREE.
17595 For example, given:
17597 template <class T> struct S { template <class U> void f(U); };
17599 if TMPL is `template <class U> void S<int>::f(U)' this will return
17600 the full template. This function will not trace past partial
17601 specializations, however. For example, given in addition:
17603 template <class T> struct S<T*> { template <class U> void f(U); };
17605 if TMPL is `template <class U> void S<int*>::f(U)' this will return
17606 `template <class T> template <class U> S<T*>::f(U)'. */
17609 most_general_template (tree decl)
17611 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
17612 an immediate specialization. */
17613 if (TREE_CODE (decl) == FUNCTION_DECL)
17615 if (DECL_TEMPLATE_INFO (decl)) {
17616 decl = DECL_TI_TEMPLATE (decl);
17618 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
17619 template friend. */
17620 if (TREE_CODE (decl) != TEMPLATE_DECL)
17626 /* Look for more and more general templates. */
17627 while (DECL_TEMPLATE_INFO (decl))
17629 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
17630 (See cp-tree.h for details.) */
17631 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
17634 if (CLASS_TYPE_P (TREE_TYPE (decl))
17635 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
17638 /* Stop if we run into an explicitly specialized class template. */
17639 if (!DECL_NAMESPACE_SCOPE_P (decl)
17640 && DECL_CONTEXT (decl)
17641 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
17644 decl = DECL_TI_TEMPLATE (decl);
17650 /* Return the most specialized of the class template partial
17651 specializations of TMPL which can produce TYPE, a specialization of
17652 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
17653 a _TYPE node corresponding to the partial specialization, while the
17654 TREE_PURPOSE is the set of template arguments that must be
17655 substituted into the TREE_TYPE in order to generate TYPE.
17657 If the choice of partial specialization is ambiguous, a diagnostic
17658 is issued, and the error_mark_node is returned. If there are no
17659 partial specializations of TMPL matching TYPE, then NULL_TREE is
17663 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
17665 tree list = NULL_TREE;
17671 tree outer_args = NULL_TREE;
17673 tmpl = most_general_template (tmpl);
17674 args = CLASSTYPE_TI_ARGS (type);
17676 /* For determining which partial specialization to use, only the
17677 innermost args are interesting. */
17678 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17680 outer_args = strip_innermost_template_args (args, 1);
17681 args = INNERMOST_TEMPLATE_ARGS (args);
17684 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
17686 tree partial_spec_args;
17688 tree parms = TREE_VALUE (t);
17690 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
17692 ++processing_template_decl;
17698 /* Discard the outer levels of args, and then substitute in the
17699 template args from the enclosing class. */
17700 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
17701 partial_spec_args = tsubst_template_args
17702 (partial_spec_args, outer_args, tf_none, NULL_TREE);
17704 /* PARMS already refers to just the innermost parms, but the
17705 template parms in partial_spec_args had their levels lowered
17706 by tsubst, so we need to do the same for the parm list. We
17707 can't just tsubst the TREE_VEC itself, as tsubst wants to
17708 treat a TREE_VEC as an argument vector. */
17709 parms = copy_node (parms);
17710 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
17711 TREE_VEC_ELT (parms, i) =
17712 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
17716 partial_spec_args =
17717 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17718 add_to_template_args (outer_args,
17719 partial_spec_args),
17721 /*require_all_args=*/true,
17722 /*use_default_args=*/true);
17724 --processing_template_decl;
17726 if (partial_spec_args == error_mark_node)
17727 return error_mark_node;
17729 spec_args = get_class_bindings (parms,
17735 spec_args = add_to_template_args (outer_args, spec_args);
17736 list = tree_cons (spec_args, TREE_VALUE (t), list);
17737 TREE_TYPE (list) = TREE_TYPE (t);
17744 ambiguous_p = false;
17747 t = TREE_CHAIN (t);
17748 for (; t; t = TREE_CHAIN (t))
17750 fate = more_specialized_class (champ, t);
17757 t = TREE_CHAIN (t);
17760 ambiguous_p = true;
17769 for (t = list; t && t != champ; t = TREE_CHAIN (t))
17771 fate = more_specialized_class (champ, t);
17774 ambiguous_p = true;
17782 char *spaces = NULL;
17783 if (!(complain & tf_error))
17784 return error_mark_node;
17785 error ("ambiguous class template instantiation for %q#T", type);
17786 str = ngettext ("candidate is:", "candidates are:", list_length (list));
17787 for (t = list; t; t = TREE_CHAIN (t))
17789 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
17790 spaces = spaces ? spaces : get_spaces (str);
17793 return error_mark_node;
17799 /* Explicitly instantiate DECL. */
17802 do_decl_instantiation (tree decl, tree storage)
17804 tree result = NULL_TREE;
17807 if (!decl || decl == error_mark_node)
17808 /* An error occurred, for which grokdeclarator has already issued
17809 an appropriate message. */
17811 else if (! DECL_LANG_SPECIFIC (decl))
17813 error ("explicit instantiation of non-template %q#D", decl);
17816 else if (TREE_CODE (decl) == VAR_DECL)
17818 /* There is an asymmetry here in the way VAR_DECLs and
17819 FUNCTION_DECLs are handled by grokdeclarator. In the case of
17820 the latter, the DECL we get back will be marked as a
17821 template instantiation, and the appropriate
17822 DECL_TEMPLATE_INFO will be set up. This does not happen for
17823 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
17824 should handle VAR_DECLs as it currently handles
17826 if (!DECL_CLASS_SCOPE_P (decl))
17828 error ("%qD is not a static data member of a class template", decl);
17831 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
17832 if (!result || TREE_CODE (result) != VAR_DECL)
17834 error ("no matching template for %qD found", decl);
17837 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
17839 error ("type %qT for explicit instantiation %qD does not match "
17840 "declared type %qT", TREE_TYPE (result), decl,
17845 else if (TREE_CODE (decl) != FUNCTION_DECL)
17847 error ("explicit instantiation of %q#D", decl);
17853 /* Check for various error cases. Note that if the explicit
17854 instantiation is valid the RESULT will currently be marked as an
17855 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
17856 until we get here. */
17858 if (DECL_TEMPLATE_SPECIALIZATION (result))
17860 /* DR 259 [temp.spec].
17862 Both an explicit instantiation and a declaration of an explicit
17863 specialization shall not appear in a program unless the explicit
17864 instantiation follows a declaration of the explicit specialization.
17866 For a given set of template parameters, if an explicit
17867 instantiation of a template appears after a declaration of an
17868 explicit specialization for that template, the explicit
17869 instantiation has no effect. */
17872 else if (DECL_EXPLICIT_INSTANTIATION (result))
17876 No program shall explicitly instantiate any template more
17879 We check DECL_NOT_REALLY_EXTERN so as not to complain when
17880 the first instantiation was `extern' and the second is not,
17881 and EXTERN_P for the opposite case. */
17882 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
17883 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
17884 /* If an "extern" explicit instantiation follows an ordinary
17885 explicit instantiation, the template is instantiated. */
17889 else if (!DECL_IMPLICIT_INSTANTIATION (result))
17891 error ("no matching template for %qD found", result);
17894 else if (!DECL_TEMPLATE_INFO (result))
17896 permerror (input_location, "explicit instantiation of non-template %q#D", result);
17900 if (storage == NULL_TREE)
17902 else if (storage == ridpointers[(int) RID_EXTERN])
17904 if (!in_system_header && (cxx_dialect == cxx98))
17905 pedwarn (input_location, OPT_pedantic,
17906 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
17911 error ("storage class %qD applied to template instantiation", storage);
17913 check_explicit_instantiation_namespace (result);
17914 mark_decl_instantiated (result, extern_p);
17916 instantiate_decl (result, /*defer_ok=*/1,
17917 /*expl_inst_class_mem_p=*/false);
17921 mark_class_instantiated (tree t, int extern_p)
17923 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
17924 SET_CLASSTYPE_INTERFACE_KNOWN (t);
17925 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
17926 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
17929 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
17930 rest_of_type_compilation (t, 1);
17934 /* Called from do_type_instantiation through binding_table_foreach to
17935 do recursive instantiation for the type bound in ENTRY. */
17937 bt_instantiate_type_proc (binding_entry entry, void *data)
17939 tree storage = *(tree *) data;
17941 if (MAYBE_CLASS_TYPE_P (entry->type)
17942 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
17943 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
17946 /* Called from do_type_instantiation to instantiate a member
17947 (a member function or a static member variable) of an
17948 explicitly instantiated class template. */
17950 instantiate_class_member (tree decl, int extern_p)
17952 mark_decl_instantiated (decl, extern_p);
17954 instantiate_decl (decl, /*defer_ok=*/1,
17955 /*expl_inst_class_mem_p=*/true);
17958 /* Perform an explicit instantiation of template class T. STORAGE, if
17959 non-null, is the RID for extern, inline or static. COMPLAIN is
17960 nonzero if this is called from the parser, zero if called recursively,
17961 since the standard is unclear (as detailed below). */
17964 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
17969 int previous_instantiation_extern_p = 0;
17971 if (TREE_CODE (t) == TYPE_DECL)
17974 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
17977 (TYPE_TEMPLATE_INFO (t)) ? TYPE_TI_TEMPLATE (t) : NULL;
17979 error ("explicit instantiation of non-class template %qD", tmpl);
17981 error ("explicit instantiation of non-template type %qT", t);
17987 if (!COMPLETE_TYPE_P (t))
17989 if (complain & tf_error)
17990 error ("explicit instantiation of %q#T before definition of template",
17995 if (storage != NULL_TREE)
17997 if (!in_system_header)
17999 if (storage == ridpointers[(int) RID_EXTERN])
18001 if (cxx_dialect == cxx98)
18002 pedwarn (input_location, OPT_pedantic,
18003 "ISO C++ 1998 forbids the use of %<extern%> on "
18004 "explicit instantiations");
18007 pedwarn (input_location, OPT_pedantic,
18008 "ISO C++ forbids the use of %qE"
18009 " on explicit instantiations", storage);
18012 if (storage == ridpointers[(int) RID_INLINE])
18014 else if (storage == ridpointers[(int) RID_EXTERN])
18016 else if (storage == ridpointers[(int) RID_STATIC])
18020 error ("storage class %qD applied to template instantiation",
18026 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
18028 /* DR 259 [temp.spec].
18030 Both an explicit instantiation and a declaration of an explicit
18031 specialization shall not appear in a program unless the explicit
18032 instantiation follows a declaration of the explicit specialization.
18034 For a given set of template parameters, if an explicit
18035 instantiation of a template appears after a declaration of an
18036 explicit specialization for that template, the explicit
18037 instantiation has no effect. */
18040 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
18044 No program shall explicitly instantiate any template more
18047 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
18048 instantiation was `extern'. If EXTERN_P then the second is.
18049 These cases are OK. */
18050 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
18052 if (!previous_instantiation_extern_p && !extern_p
18053 && (complain & tf_error))
18054 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
18056 /* If we've already instantiated the template, just return now. */
18057 if (!CLASSTYPE_INTERFACE_ONLY (t))
18061 check_explicit_instantiation_namespace (TYPE_NAME (t));
18062 mark_class_instantiated (t, extern_p);
18070 /* In contrast to implicit instantiation, where only the
18071 declarations, and not the definitions, of members are
18072 instantiated, we have here:
18076 The explicit instantiation of a class template specialization
18077 implies the instantiation of all of its members not
18078 previously explicitly specialized in the translation unit
18079 containing the explicit instantiation.
18081 Of course, we can't instantiate member template classes, since
18082 we don't have any arguments for them. Note that the standard
18083 is unclear on whether the instantiation of the members are
18084 *explicit* instantiations or not. However, the most natural
18085 interpretation is that it should be an explicit instantiation. */
18088 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
18089 if (TREE_CODE (tmp) == FUNCTION_DECL
18090 && DECL_TEMPLATE_INSTANTIATION (tmp))
18091 instantiate_class_member (tmp, extern_p);
18093 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
18094 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
18095 instantiate_class_member (tmp, extern_p);
18097 if (CLASSTYPE_NESTED_UTDS (t))
18098 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
18099 bt_instantiate_type_proc, &storage);
18103 /* Given a function DECL, which is a specialization of TMPL, modify
18104 DECL to be a re-instantiation of TMPL with the same template
18105 arguments. TMPL should be the template into which tsubst'ing
18106 should occur for DECL, not the most general template.
18108 One reason for doing this is a scenario like this:
18111 void f(const T&, int i);
18113 void g() { f(3, 7); }
18116 void f(const T& t, const int i) { }
18118 Note that when the template is first instantiated, with
18119 instantiate_template, the resulting DECL will have no name for the
18120 first parameter, and the wrong type for the second. So, when we go
18121 to instantiate the DECL, we regenerate it. */
18124 regenerate_decl_from_template (tree decl, tree tmpl)
18126 /* The arguments used to instantiate DECL, from the most general
18131 args = DECL_TI_ARGS (decl);
18132 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
18134 /* Make sure that we can see identifiers, and compute access
18136 push_access_scope (decl);
18138 if (TREE_CODE (decl) == FUNCTION_DECL)
18146 args_depth = TMPL_ARGS_DEPTH (args);
18147 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
18148 if (args_depth > parms_depth)
18149 args = get_innermost_template_args (args, parms_depth);
18151 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
18152 args, tf_error, NULL_TREE,
18153 /*defer_ok*/false);
18154 if (specs && specs != error_mark_node)
18155 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
18158 /* Merge parameter declarations. */
18159 decl_parm = skip_artificial_parms_for (decl,
18160 DECL_ARGUMENTS (decl));
18162 = skip_artificial_parms_for (code_pattern,
18163 DECL_ARGUMENTS (code_pattern));
18164 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
18169 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18170 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
18171 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
18173 parm_type = type_decays_to (parm_type);
18174 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18175 TREE_TYPE (decl_parm) = parm_type;
18176 attributes = DECL_ATTRIBUTES (pattern_parm);
18177 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18179 DECL_ATTRIBUTES (decl_parm) = attributes;
18180 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18182 decl_parm = DECL_CHAIN (decl_parm);
18183 pattern_parm = DECL_CHAIN (pattern_parm);
18185 /* Merge any parameters that match with the function parameter
18187 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
18190 tree expanded_types;
18191 /* Expand the TYPE_PACK_EXPANSION that provides the types for
18192 the parameters in this function parameter pack. */
18193 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
18194 args, tf_error, NULL_TREE);
18195 len = TREE_VEC_LENGTH (expanded_types);
18196 for (i = 0; i < len; i++)
18201 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18202 /* Rename the parameter to include the index. */
18203 DECL_NAME (decl_parm) =
18204 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
18205 parm_type = TREE_VEC_ELT (expanded_types, i);
18206 parm_type = type_decays_to (parm_type);
18207 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18208 TREE_TYPE (decl_parm) = parm_type;
18209 attributes = DECL_ATTRIBUTES (pattern_parm);
18210 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18212 DECL_ATTRIBUTES (decl_parm) = attributes;
18213 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18215 decl_parm = DECL_CHAIN (decl_parm);
18218 /* Merge additional specifiers from the CODE_PATTERN. */
18219 if (DECL_DECLARED_INLINE_P (code_pattern)
18220 && !DECL_DECLARED_INLINE_P (decl))
18221 DECL_DECLARED_INLINE_P (decl) = 1;
18223 else if (TREE_CODE (decl) == VAR_DECL)
18225 DECL_INITIAL (decl) =
18226 tsubst_expr (DECL_INITIAL (code_pattern), args,
18227 tf_error, DECL_TI_TEMPLATE (decl),
18228 /*integral_constant_expression_p=*/false);
18229 if (VAR_HAD_UNKNOWN_BOUND (decl))
18230 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
18231 tf_error, DECL_TI_TEMPLATE (decl));
18234 gcc_unreachable ();
18236 pop_access_scope (decl);
18239 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
18240 substituted to get DECL. */
18243 template_for_substitution (tree decl)
18245 tree tmpl = DECL_TI_TEMPLATE (decl);
18247 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
18248 for the instantiation. This is not always the most general
18249 template. Consider, for example:
18252 struct S { template <class U> void f();
18253 template <> void f<int>(); };
18255 and an instantiation of S<double>::f<int>. We want TD to be the
18256 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
18257 while (/* An instantiation cannot have a definition, so we need a
18258 more general template. */
18259 DECL_TEMPLATE_INSTANTIATION (tmpl)
18260 /* We must also deal with friend templates. Given:
18262 template <class T> struct S {
18263 template <class U> friend void f() {};
18266 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
18267 so far as the language is concerned, but that's still
18268 where we get the pattern for the instantiation from. On
18269 other hand, if the definition comes outside the class, say:
18271 template <class T> struct S {
18272 template <class U> friend void f();
18274 template <class U> friend void f() {}
18276 we don't need to look any further. That's what the check for
18277 DECL_INITIAL is for. */
18278 || (TREE_CODE (decl) == FUNCTION_DECL
18279 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
18280 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
18282 /* The present template, TD, should not be a definition. If it
18283 were a definition, we should be using it! Note that we
18284 cannot restructure the loop to just keep going until we find
18285 a template with a definition, since that might go too far if
18286 a specialization was declared, but not defined. */
18287 gcc_assert (TREE_CODE (decl) != VAR_DECL
18288 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
18290 /* Fetch the more general template. */
18291 tmpl = DECL_TI_TEMPLATE (tmpl);
18297 /* Returns true if we need to instantiate this template instance even if we
18298 know we aren't going to emit it.. */
18301 always_instantiate_p (tree decl)
18303 /* We always instantiate inline functions so that we can inline them. An
18304 explicit instantiation declaration prohibits implicit instantiation of
18305 non-inline functions. With high levels of optimization, we would
18306 normally inline non-inline functions -- but we're not allowed to do
18307 that for "extern template" functions. Therefore, we check
18308 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
18309 return ((TREE_CODE (decl) == FUNCTION_DECL
18310 && DECL_DECLARED_INLINE_P (decl))
18311 /* And we need to instantiate static data members so that
18312 their initializers are available in integral constant
18314 || (TREE_CODE (decl) == VAR_DECL
18315 && decl_maybe_constant_var_p (decl)));
18318 /* If FN has a noexcept-specifier that hasn't been instantiated yet,
18319 instantiate it now, modifying TREE_TYPE (fn). */
18322 maybe_instantiate_noexcept (tree fn)
18324 tree fntype, spec, noex, clone;
18326 if (DECL_CLONED_FUNCTION_P (fn))
18327 fn = DECL_CLONED_FUNCTION (fn);
18328 fntype = TREE_TYPE (fn);
18329 spec = TYPE_RAISES_EXCEPTIONS (fntype);
18331 if (!DEFERRED_NOEXCEPT_SPEC_P (spec))
18334 noex = TREE_PURPOSE (spec);
18336 if (TREE_CODE (noex) == DEFERRED_NOEXCEPT)
18338 if (push_tinst_level (fn))
18340 push_access_scope (fn);
18341 input_location = DECL_SOURCE_LOCATION (fn);
18342 noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex),
18343 DEFERRED_NOEXCEPT_ARGS (noex),
18344 tf_warning_or_error, fn,
18345 /*function_p=*/false,
18346 /*integral_constant_expression_p=*/true);
18347 pop_access_scope (fn);
18348 pop_tinst_level ();
18349 spec = build_noexcept_spec (noex, tf_warning_or_error);
18350 if (spec == error_mark_node)
18351 spec = noexcept_false_spec;
18354 spec = noexcept_false_spec;
18358 /* This is an implicitly declared function, so NOEX is a list of
18359 other functions to evaluate and merge. */
18361 spec = noexcept_true_spec;
18362 for (elt = noex; elt; elt = OVL_NEXT (elt))
18364 tree fn = OVL_CURRENT (elt);
18366 maybe_instantiate_noexcept (fn);
18367 subspec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn));
18368 spec = merge_exception_specifiers (spec, subspec, NULL_TREE);
18372 TREE_TYPE (fn) = build_exception_variant (fntype, spec);
18374 FOR_EACH_CLONE (clone, fn)
18376 if (TREE_TYPE (clone) == fntype)
18377 TREE_TYPE (clone) = TREE_TYPE (fn);
18379 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone), spec);
18383 /* Produce the definition of D, a _DECL generated from a template. If
18384 DEFER_OK is nonzero, then we don't have to actually do the
18385 instantiation now; we just have to do it sometime. Normally it is
18386 an error if this is an explicit instantiation but D is undefined.
18387 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
18388 explicitly instantiated class template. */
18391 instantiate_decl (tree d, int defer_ok,
18392 bool expl_inst_class_mem_p)
18394 tree tmpl = DECL_TI_TEMPLATE (d);
18401 bool pattern_defined;
18403 location_t saved_loc = input_location;
18406 /* This function should only be used to instantiate templates for
18407 functions and static member variables. */
18408 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
18409 || TREE_CODE (d) == VAR_DECL);
18411 /* Variables are never deferred; if instantiation is required, they
18412 are instantiated right away. That allows for better code in the
18413 case that an expression refers to the value of the variable --
18414 if the variable has a constant value the referring expression can
18415 take advantage of that fact. */
18416 if (TREE_CODE (d) == VAR_DECL
18417 || DECL_DECLARED_CONSTEXPR_P (d))
18420 /* Don't instantiate cloned functions. Instead, instantiate the
18421 functions they cloned. */
18422 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
18423 d = DECL_CLONED_FUNCTION (d);
18425 if (DECL_TEMPLATE_INSTANTIATED (d)
18426 || (TREE_CODE (d) == FUNCTION_DECL
18427 && DECL_DEFAULTED_FN (d) && DECL_INITIAL (d))
18428 || DECL_TEMPLATE_SPECIALIZATION (d))
18429 /* D has already been instantiated or explicitly specialized, so
18430 there's nothing for us to do here.
18432 It might seem reasonable to check whether or not D is an explicit
18433 instantiation, and, if so, stop here. But when an explicit
18434 instantiation is deferred until the end of the compilation,
18435 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
18436 the instantiation. */
18439 /* Check to see whether we know that this template will be
18440 instantiated in some other file, as with "extern template"
18442 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
18444 /* In general, we do not instantiate such templates. */
18445 if (external_p && !always_instantiate_p (d))
18448 gen_tmpl = most_general_template (tmpl);
18449 gen_args = DECL_TI_ARGS (d);
18451 if (tmpl != gen_tmpl)
18452 /* We should already have the extra args. */
18453 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
18454 == TMPL_ARGS_DEPTH (gen_args));
18455 /* And what's in the hash table should match D. */
18456 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
18457 || spec == NULL_TREE);
18459 /* This needs to happen before any tsubsting. */
18460 if (! push_tinst_level (d))
18463 timevar_push (TV_TEMPLATE_INST);
18465 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
18466 for the instantiation. */
18467 td = template_for_substitution (d);
18468 code_pattern = DECL_TEMPLATE_RESULT (td);
18470 /* We should never be trying to instantiate a member of a class
18471 template or partial specialization. */
18472 gcc_assert (d != code_pattern);
18474 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
18475 || DECL_TEMPLATE_SPECIALIZATION (td))
18476 /* In the case of a friend template whose definition is provided
18477 outside the class, we may have too many arguments. Drop the
18478 ones we don't need. The same is true for specializations. */
18479 args = get_innermost_template_args
18480 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
18484 if (TREE_CODE (d) == FUNCTION_DECL)
18485 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE
18486 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern));
18488 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
18490 /* We may be in the middle of deferred access check. Disable it now. */
18491 push_deferring_access_checks (dk_no_deferred);
18493 /* Unless an explicit instantiation directive has already determined
18494 the linkage of D, remember that a definition is available for
18496 if (pattern_defined
18497 && !DECL_INTERFACE_KNOWN (d)
18498 && !DECL_NOT_REALLY_EXTERN (d))
18499 mark_definable (d);
18501 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
18502 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
18503 input_location = DECL_SOURCE_LOCATION (d);
18505 /* If D is a member of an explicitly instantiated class template,
18506 and no definition is available, treat it like an implicit
18508 if (!pattern_defined && expl_inst_class_mem_p
18509 && DECL_EXPLICIT_INSTANTIATION (d))
18511 /* Leave linkage flags alone on instantiations with anonymous
18513 if (TREE_PUBLIC (d))
18515 DECL_NOT_REALLY_EXTERN (d) = 0;
18516 DECL_INTERFACE_KNOWN (d) = 0;
18518 SET_DECL_IMPLICIT_INSTANTIATION (d);
18521 if (TREE_CODE (d) == FUNCTION_DECL)
18522 maybe_instantiate_noexcept (d);
18524 /* Recheck the substitutions to obtain any warning messages
18525 about ignoring cv qualifiers. Don't do this for artificial decls,
18526 as it breaks the context-sensitive substitution for lambda op(). */
18527 if (!defer_ok && !DECL_ARTIFICIAL (d))
18529 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
18530 tree type = TREE_TYPE (gen);
18532 /* Make sure that we can see identifiers, and compute access
18533 correctly. D is already the target FUNCTION_DECL with the
18535 push_access_scope (d);
18537 if (TREE_CODE (gen) == FUNCTION_DECL)
18539 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
18540 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
18541 d, /*defer_ok*/true);
18542 /* Don't simply tsubst the function type, as that will give
18543 duplicate warnings about poor parameter qualifications.
18544 The function arguments are the same as the decl_arguments
18545 without the top level cv qualifiers. */
18546 type = TREE_TYPE (type);
18548 tsubst (type, gen_args, tf_warning_or_error, d);
18550 pop_access_scope (d);
18553 /* Defer all other templates, unless we have been explicitly
18554 forbidden from doing so. */
18555 if (/* If there is no definition, we cannot instantiate the
18558 /* If it's OK to postpone instantiation, do so. */
18560 /* If this is a static data member that will be defined
18561 elsewhere, we don't want to instantiate the entire data
18562 member, but we do want to instantiate the initializer so that
18563 we can substitute that elsewhere. */
18564 || (external_p && TREE_CODE (d) == VAR_DECL))
18566 /* The definition of the static data member is now required so
18567 we must substitute the initializer. */
18568 if (TREE_CODE (d) == VAR_DECL
18569 && !DECL_INITIAL (d)
18570 && DECL_INITIAL (code_pattern))
18574 bool const_init = false;
18576 ns = decl_namespace_context (d);
18577 push_nested_namespace (ns);
18578 push_nested_class (DECL_CONTEXT (d));
18579 init = tsubst_expr (DECL_INITIAL (code_pattern),
18581 tf_warning_or_error, NULL_TREE,
18582 /*integral_constant_expression_p=*/false);
18583 /* Make sure the initializer is still constant, in case of
18584 circular dependency (template/instantiate6.C). */
18586 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18587 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
18588 /*asmspec_tree=*/NULL_TREE,
18589 LOOKUP_ONLYCONVERTING);
18590 pop_nested_class ();
18591 pop_nested_namespace (ns);
18594 /* We restore the source position here because it's used by
18595 add_pending_template. */
18596 input_location = saved_loc;
18598 if (at_eof && !pattern_defined
18599 && DECL_EXPLICIT_INSTANTIATION (d)
18600 && DECL_NOT_REALLY_EXTERN (d))
18603 The definition of a non-exported function template, a
18604 non-exported member function template, or a non-exported
18605 member function or static data member of a class template
18606 shall be present in every translation unit in which it is
18607 explicitly instantiated. */
18608 permerror (input_location, "explicit instantiation of %qD "
18609 "but no definition available", d);
18611 /* If we're in unevaluated context, we just wanted to get the
18612 constant value; this isn't an odr use, so don't queue
18613 a full instantiation. */
18614 if (cp_unevaluated_operand != 0)
18616 /* ??? Historically, we have instantiated inline functions, even
18617 when marked as "extern template". */
18618 if (!(external_p && TREE_CODE (d) == VAR_DECL))
18619 add_pending_template (d);
18622 /* Tell the repository that D is available in this translation unit
18623 -- and see if it is supposed to be instantiated here. */
18624 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
18626 /* In a PCH file, despite the fact that the repository hasn't
18627 requested instantiation in the PCH it is still possible that
18628 an instantiation will be required in a file that includes the
18631 add_pending_template (d);
18632 /* Instantiate inline functions so that the inliner can do its
18633 job, even though we'll not be emitting a copy of this
18635 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
18639 need_push = !cfun || !global_bindings_p ();
18641 push_to_top_level ();
18643 /* Mark D as instantiated so that recursive calls to
18644 instantiate_decl do not try to instantiate it again. */
18645 DECL_TEMPLATE_INSTANTIATED (d) = 1;
18647 /* Regenerate the declaration in case the template has been modified
18648 by a subsequent redeclaration. */
18649 regenerate_decl_from_template (d, td);
18651 /* We already set the file and line above. Reset them now in case
18652 they changed as a result of calling regenerate_decl_from_template. */
18653 input_location = DECL_SOURCE_LOCATION (d);
18655 if (TREE_CODE (d) == VAR_DECL)
18658 bool const_init = false;
18660 /* Clear out DECL_RTL; whatever was there before may not be right
18661 since we've reset the type of the declaration. */
18662 SET_DECL_RTL (d, NULL);
18663 DECL_IN_AGGR_P (d) = 0;
18665 /* The initializer is placed in DECL_INITIAL by
18666 regenerate_decl_from_template so we don't need to
18667 push/pop_access_scope again here. Pull it out so that
18668 cp_finish_decl can process it. */
18669 init = DECL_INITIAL (d);
18670 DECL_INITIAL (d) = NULL_TREE;
18671 DECL_INITIALIZED_P (d) = 0;
18673 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
18674 initializer. That function will defer actual emission until
18675 we have a chance to determine linkage. */
18676 DECL_EXTERNAL (d) = 0;
18678 /* Enter the scope of D so that access-checking works correctly. */
18679 push_nested_class (DECL_CONTEXT (d));
18680 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18681 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
18682 pop_nested_class ();
18684 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern))
18685 synthesize_method (d);
18686 else if (TREE_CODE (d) == FUNCTION_DECL)
18688 htab_t saved_local_specializations;
18693 /* Save away the current list, in case we are instantiating one
18694 template from within the body of another. */
18695 saved_local_specializations = local_specializations;
18697 /* Set up the list of local specializations. */
18698 local_specializations = htab_create (37,
18699 hash_local_specialization,
18700 eq_local_specializations,
18703 /* Set up context. */
18704 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
18706 /* Create substitution entries for the parameters. */
18707 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
18708 tmpl_parm = DECL_ARGUMENTS (subst_decl);
18709 spec_parm = DECL_ARGUMENTS (d);
18710 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
18712 register_local_specialization (spec_parm, tmpl_parm);
18713 spec_parm = skip_artificial_parms_for (d, spec_parm);
18714 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
18716 for (; tmpl_parm; tmpl_parm = DECL_CHAIN (tmpl_parm))
18718 if (!FUNCTION_PARAMETER_PACK_P (tmpl_parm))
18720 register_local_specialization (spec_parm, tmpl_parm);
18721 spec_parm = DECL_CHAIN (spec_parm);
18725 /* Register the (value) argument pack as a specialization of
18726 TMPL_PARM, then move on. */
18727 tree argpack = extract_fnparm_pack (tmpl_parm, &spec_parm);
18728 register_local_specialization (argpack, tmpl_parm);
18731 gcc_assert (!spec_parm);
18733 /* Substitute into the body of the function. */
18734 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
18735 tf_warning_or_error, tmpl,
18736 /*integral_constant_expression_p=*/false);
18738 /* Set the current input_location to the end of the function
18739 so that finish_function knows where we are. */
18740 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
18742 /* We don't need the local specializations any more. */
18743 htab_delete (local_specializations);
18744 local_specializations = saved_local_specializations;
18746 /* Finish the function. */
18747 d = finish_function (0);
18748 expand_or_defer_fn (d);
18751 /* We're not deferring instantiation any more. */
18752 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
18755 pop_from_top_level ();
18758 input_location = saved_loc;
18759 pop_deferring_access_checks ();
18760 pop_tinst_level ();
18762 timevar_pop (TV_TEMPLATE_INST);
18767 /* Run through the list of templates that we wish we could
18768 instantiate, and instantiate any we can. RETRIES is the
18769 number of times we retry pending template instantiation. */
18772 instantiate_pending_templates (int retries)
18775 location_t saved_loc = input_location;
18777 /* Instantiating templates may trigger vtable generation. This in turn
18778 may require further template instantiations. We place a limit here
18779 to avoid infinite loop. */
18780 if (pending_templates && retries >= max_tinst_depth)
18782 tree decl = pending_templates->tinst->decl;
18784 error ("template instantiation depth exceeds maximum of %d"
18785 " instantiating %q+D, possibly from virtual table generation"
18786 " (use -ftemplate-depth= to increase the maximum)",
18787 max_tinst_depth, decl);
18788 if (TREE_CODE (decl) == FUNCTION_DECL)
18789 /* Pretend that we defined it. */
18790 DECL_INITIAL (decl) = error_mark_node;
18796 struct pending_template **t = &pending_templates;
18797 struct pending_template *last = NULL;
18801 tree instantiation = reopen_tinst_level ((*t)->tinst);
18802 bool complete = false;
18804 if (TYPE_P (instantiation))
18808 if (!COMPLETE_TYPE_P (instantiation))
18810 instantiate_class_template (instantiation);
18811 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
18812 for (fn = TYPE_METHODS (instantiation);
18814 fn = TREE_CHAIN (fn))
18815 if (! DECL_ARTIFICIAL (fn))
18816 instantiate_decl (fn,
18818 /*expl_inst_class_mem_p=*/false);
18819 if (COMPLETE_TYPE_P (instantiation))
18823 complete = COMPLETE_TYPE_P (instantiation);
18827 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
18828 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
18831 = instantiate_decl (instantiation,
18833 /*expl_inst_class_mem_p=*/false);
18834 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
18838 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
18839 || DECL_TEMPLATE_INSTANTIATED (instantiation));
18843 /* If INSTANTIATION has been instantiated, then we don't
18844 need to consider it again in the future. */
18852 current_tinst_level = NULL;
18854 last_pending_template = last;
18856 while (reconsider);
18858 input_location = saved_loc;
18861 /* Substitute ARGVEC into T, which is a list of initializers for
18862 either base class or a non-static data member. The TREE_PURPOSEs
18863 are DECLs, and the TREE_VALUEs are the initializer values. Used by
18864 instantiate_decl. */
18867 tsubst_initializer_list (tree t, tree argvec)
18869 tree inits = NULL_TREE;
18871 for (; t; t = TREE_CHAIN (t))
18875 tree expanded_bases = NULL_TREE;
18876 tree expanded_arguments = NULL_TREE;
18879 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
18884 /* Expand the base class expansion type into separate base
18886 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
18887 tf_warning_or_error,
18889 if (expanded_bases == error_mark_node)
18892 /* We'll be building separate TREE_LISTs of arguments for
18894 len = TREE_VEC_LENGTH (expanded_bases);
18895 expanded_arguments = make_tree_vec (len);
18896 for (i = 0; i < len; i++)
18897 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
18899 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
18900 expand each argument in the TREE_VALUE of t. */
18901 expr = make_node (EXPR_PACK_EXPANSION);
18902 PACK_EXPANSION_PARAMETER_PACKS (expr) =
18903 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
18905 if (TREE_VALUE (t) == void_type_node)
18906 /* VOID_TYPE_NODE is used to indicate
18907 value-initialization. */
18909 for (i = 0; i < len; i++)
18910 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
18914 /* Substitute parameter packs into each argument in the
18916 in_base_initializer = 1;
18917 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
18919 tree expanded_exprs;
18921 /* Expand the argument. */
18922 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
18924 = tsubst_pack_expansion (expr, argvec,
18925 tf_warning_or_error,
18927 if (expanded_exprs == error_mark_node)
18930 /* Prepend each of the expanded expressions to the
18931 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
18932 for (i = 0; i < len; i++)
18934 TREE_VEC_ELT (expanded_arguments, i) =
18935 tree_cons (NULL_TREE,
18936 TREE_VEC_ELT (expanded_exprs, i),
18937 TREE_VEC_ELT (expanded_arguments, i));
18940 in_base_initializer = 0;
18942 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
18943 since we built them backwards. */
18944 for (i = 0; i < len; i++)
18946 TREE_VEC_ELT (expanded_arguments, i) =
18947 nreverse (TREE_VEC_ELT (expanded_arguments, i));
18952 for (i = 0; i < len; ++i)
18954 if (expanded_bases)
18956 decl = TREE_VEC_ELT (expanded_bases, i);
18957 decl = expand_member_init (decl);
18958 init = TREE_VEC_ELT (expanded_arguments, i);
18962 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
18963 tf_warning_or_error, NULL_TREE);
18965 decl = expand_member_init (decl);
18966 if (decl && !DECL_P (decl))
18967 in_base_initializer = 1;
18969 init = TREE_VALUE (t);
18970 if (init != void_type_node)
18971 init = tsubst_expr (init, argvec,
18972 tf_warning_or_error, NULL_TREE,
18973 /*integral_constant_expression_p=*/false);
18974 in_base_initializer = 0;
18979 init = build_tree_list (decl, init);
18980 TREE_CHAIN (init) = inits;
18988 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
18991 set_current_access_from_decl (tree decl)
18993 if (TREE_PRIVATE (decl))
18994 current_access_specifier = access_private_node;
18995 else if (TREE_PROTECTED (decl))
18996 current_access_specifier = access_protected_node;
18998 current_access_specifier = access_public_node;
19001 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
19002 is the instantiation (which should have been created with
19003 start_enum) and ARGS are the template arguments to use. */
19006 tsubst_enum (tree tag, tree newtag, tree args)
19010 if (SCOPED_ENUM_P (newtag))
19011 begin_scope (sk_scoped_enum, newtag);
19013 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
19018 decl = TREE_VALUE (e);
19019 /* Note that in a template enum, the TREE_VALUE is the
19020 CONST_DECL, not the corresponding INTEGER_CST. */
19021 value = tsubst_expr (DECL_INITIAL (decl),
19022 args, tf_warning_or_error, NULL_TREE,
19023 /*integral_constant_expression_p=*/true);
19025 /* Give this enumeration constant the correct access. */
19026 set_current_access_from_decl (decl);
19028 /* Actually build the enumerator itself. */
19030 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
19033 if (SCOPED_ENUM_P (newtag))
19036 finish_enum_value_list (newtag);
19037 finish_enum (newtag);
19039 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
19040 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
19043 /* DECL is a FUNCTION_DECL that is a template specialization. Return
19044 its type -- but without substituting the innermost set of template
19045 arguments. So, innermost set of template parameters will appear in
19049 get_mostly_instantiated_function_type (tree decl)
19057 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
19058 targs = DECL_TI_ARGS (decl);
19059 tparms = DECL_TEMPLATE_PARMS (tmpl);
19060 parm_depth = TMPL_PARMS_DEPTH (tparms);
19062 /* There should be as many levels of arguments as there are levels
19064 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
19066 fn_type = TREE_TYPE (tmpl);
19068 if (parm_depth == 1)
19069 /* No substitution is necessary. */
19076 /* Replace the innermost level of the TARGS with NULL_TREEs to
19077 let tsubst know not to substitute for those parameters. */
19078 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
19079 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
19080 SET_TMPL_ARGS_LEVEL (partial_args, i,
19081 TMPL_ARGS_LEVEL (targs, i));
19082 SET_TMPL_ARGS_LEVEL (partial_args,
19083 TMPL_ARGS_DEPTH (targs),
19084 make_tree_vec (DECL_NTPARMS (tmpl)));
19086 /* Make sure that we can see identifiers, and compute access
19088 push_access_scope (decl);
19090 ++processing_template_decl;
19091 /* Now, do the (partial) substitution to figure out the
19092 appropriate function type. */
19093 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
19094 --processing_template_decl;
19096 /* Substitute into the template parameters to obtain the real
19097 innermost set of parameters. This step is important if the
19098 innermost set of template parameters contains value
19099 parameters whose types depend on outer template parameters. */
19100 TREE_VEC_LENGTH (partial_args)--;
19101 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
19103 pop_access_scope (decl);
19109 /* Return truthvalue if we're processing a template different from
19110 the last one involved in diagnostics. */
19112 problematic_instantiation_changed (void)
19114 return current_tinst_level != last_error_tinst_level;
19117 /* Remember current template involved in diagnostics. */
19119 record_last_problematic_instantiation (void)
19121 last_error_tinst_level = current_tinst_level;
19124 struct tinst_level *
19125 current_instantiation (void)
19127 return current_tinst_level;
19130 /* [temp.param] Check that template non-type parm TYPE is of an allowable
19131 type. Return zero for ok, nonzero for disallowed. Issue error and
19132 warning messages under control of COMPLAIN. */
19135 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
19137 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
19139 else if (POINTER_TYPE_P (type))
19141 else if (TYPE_PTR_TO_MEMBER_P (type))
19143 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
19145 else if (TREE_CODE (type) == TYPENAME_TYPE)
19147 else if (TREE_CODE (type) == DECLTYPE_TYPE)
19149 else if (TREE_CODE (type) == NULLPTR_TYPE)
19152 if (complain & tf_error)
19154 if (type == error_mark_node)
19155 inform (input_location, "invalid template non-type parameter");
19157 error ("%q#T is not a valid type for a template non-type parameter",
19163 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
19164 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
19167 dependent_type_p_r (tree type)
19173 A type is dependent if it is:
19175 -- a template parameter. Template template parameters are types
19176 for us (since TYPE_P holds true for them) so we handle
19178 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19179 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
19181 /* -- a qualified-id with a nested-name-specifier which contains a
19182 class-name that names a dependent type or whose unqualified-id
19183 names a dependent type. */
19184 if (TREE_CODE (type) == TYPENAME_TYPE)
19186 /* -- a cv-qualified type where the cv-unqualified type is
19188 type = TYPE_MAIN_VARIANT (type);
19189 /* -- a compound type constructed from any dependent type. */
19190 if (TYPE_PTR_TO_MEMBER_P (type))
19191 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
19192 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
19194 else if (TREE_CODE (type) == POINTER_TYPE
19195 || TREE_CODE (type) == REFERENCE_TYPE)
19196 return dependent_type_p (TREE_TYPE (type));
19197 else if (TREE_CODE (type) == FUNCTION_TYPE
19198 || TREE_CODE (type) == METHOD_TYPE)
19202 if (dependent_type_p (TREE_TYPE (type)))
19204 for (arg_type = TYPE_ARG_TYPES (type);
19206 arg_type = TREE_CHAIN (arg_type))
19207 if (dependent_type_p (TREE_VALUE (arg_type)))
19211 /* -- an array type constructed from any dependent type or whose
19212 size is specified by a constant expression that is
19215 We checked for type- and value-dependence of the bounds in
19216 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
19217 if (TREE_CODE (type) == ARRAY_TYPE)
19219 if (TYPE_DOMAIN (type)
19220 && dependent_type_p (TYPE_DOMAIN (type)))
19222 return dependent_type_p (TREE_TYPE (type));
19225 /* -- a template-id in which either the template name is a template
19227 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
19229 /* ... or any of the template arguments is a dependent type or
19230 an expression that is type-dependent or value-dependent. */
19231 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
19232 && (any_dependent_template_arguments_p
19233 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
19236 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
19237 dependent; if the argument of the `typeof' expression is not
19238 type-dependent, then it should already been have resolved. */
19239 if (TREE_CODE (type) == TYPEOF_TYPE
19240 || TREE_CODE (type) == DECLTYPE_TYPE
19241 || TREE_CODE (type) == UNDERLYING_TYPE)
19244 /* A template argument pack is dependent if any of its packed
19246 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
19248 tree args = ARGUMENT_PACK_ARGS (type);
19249 int i, len = TREE_VEC_LENGTH (args);
19250 for (i = 0; i < len; ++i)
19251 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19255 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
19256 be template parameters. */
19257 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
19260 /* The standard does not specifically mention types that are local
19261 to template functions or local classes, but they should be
19262 considered dependent too. For example:
19264 template <int I> void f() {
19269 The size of `E' cannot be known until the value of `I' has been
19270 determined. Therefore, `E' must be considered dependent. */
19271 scope = TYPE_CONTEXT (type);
19272 if (scope && TYPE_P (scope))
19273 return dependent_type_p (scope);
19274 /* Don't use type_dependent_expression_p here, as it can lead
19275 to infinite recursion trying to determine whether a lambda
19276 nested in a lambda is dependent (c++/47687). */
19277 else if (scope && TREE_CODE (scope) == FUNCTION_DECL
19278 && DECL_LANG_SPECIFIC (scope)
19279 && DECL_TEMPLATE_INFO (scope)
19280 && (any_dependent_template_arguments_p
19281 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
19284 /* Other types are non-dependent. */
19288 /* Returns TRUE if TYPE is dependent, in the sense of
19289 [temp.dep.type]. Note that a NULL type is considered dependent. */
19292 dependent_type_p (tree type)
19294 /* If there are no template parameters in scope, then there can't be
19295 any dependent types. */
19296 if (!processing_template_decl)
19298 /* If we are not processing a template, then nobody should be
19299 providing us with a dependent type. */
19301 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
19305 /* If the type is NULL, we have not computed a type for the entity
19306 in question; in that case, the type is dependent. */
19310 /* Erroneous types can be considered non-dependent. */
19311 if (type == error_mark_node)
19314 /* If we have not already computed the appropriate value for TYPE,
19316 if (!TYPE_DEPENDENT_P_VALID (type))
19318 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
19319 TYPE_DEPENDENT_P_VALID (type) = 1;
19322 return TYPE_DEPENDENT_P (type);
19325 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
19326 lookup. In other words, a dependent type that is not the current
19330 dependent_scope_p (tree scope)
19332 return (scope && TYPE_P (scope) && dependent_type_p (scope)
19333 && !currently_open_class (scope));
19336 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
19337 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
19340 /* Note that this predicate is not appropriate for general expressions;
19341 only constant expressions (that satisfy potential_constant_expression)
19342 can be tested for value dependence.
19344 We should really also have a predicate for "instantiation-dependent".
19346 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
19347 (what about instantiation-dependent constant-expressions?)
19348 is_late_template_attribute: defer if instantiation-dependent.
19349 compute_array_index_type: proceed if constant and not t- or v-dependent
19350 if instantiation-dependent, need to remember full expression
19351 uses_template_parms: FIXME - need to audit callers
19352 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
19353 dependent_type_p [array_type]: dependent if index type is dependent
19355 static_assert - instantiation-dependent */
19358 value_dependent_expression_p (tree expression)
19360 if (!processing_template_decl)
19363 /* A name declared with a dependent type. */
19364 if (DECL_P (expression) && type_dependent_expression_p (expression))
19367 switch (TREE_CODE (expression))
19369 case IDENTIFIER_NODE:
19370 /* A name that has not been looked up -- must be dependent. */
19373 case TEMPLATE_PARM_INDEX:
19374 /* A non-type template parm. */
19378 /* A non-type template parm. */
19379 if (DECL_TEMPLATE_PARM_P (expression))
19381 return value_dependent_expression_p (DECL_INITIAL (expression));
19384 /* A constant with literal type and is initialized
19385 with an expression that is value-dependent. */
19386 if (DECL_INITIAL (expression)
19387 && decl_constant_var_p (expression)
19388 && value_dependent_expression_p (DECL_INITIAL (expression)))
19392 case DYNAMIC_CAST_EXPR:
19393 case STATIC_CAST_EXPR:
19394 case CONST_CAST_EXPR:
19395 case REINTERPRET_CAST_EXPR:
19397 /* These expressions are value-dependent if the type to which
19398 the cast occurs is dependent or the expression being casted
19399 is value-dependent. */
19401 tree type = TREE_TYPE (expression);
19403 if (dependent_type_p (type))
19406 /* A functional cast has a list of operands. */
19407 expression = TREE_OPERAND (expression, 0);
19410 /* If there are no operands, it must be an expression such
19411 as "int()". This should not happen for aggregate types
19412 because it would form non-constant expressions. */
19413 gcc_assert (cxx_dialect >= cxx0x
19414 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
19419 if (TREE_CODE (expression) == TREE_LIST)
19420 return any_value_dependent_elements_p (expression);
19422 return value_dependent_expression_p (expression);
19428 /* A `sizeof' expression is value-dependent if the operand is
19429 type-dependent or is a pack expansion. */
19430 expression = TREE_OPERAND (expression, 0);
19431 if (PACK_EXPANSION_P (expression))
19433 else if (TYPE_P (expression))
19434 return dependent_type_p (expression);
19435 return type_dependent_expression_p (expression);
19437 case AT_ENCODE_EXPR:
19438 /* An 'encode' expression is value-dependent if the operand is
19440 expression = TREE_OPERAND (expression, 0);
19441 return dependent_type_p (expression);
19443 case NOEXCEPT_EXPR:
19444 expression = TREE_OPERAND (expression, 0);
19445 return type_dependent_expression_p (expression);
19449 tree name = TREE_OPERAND (expression, 1);
19450 return value_dependent_expression_p (name);
19453 case COMPONENT_REF:
19454 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
19455 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
19457 case NONTYPE_ARGUMENT_PACK:
19458 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
19459 is value-dependent. */
19461 tree values = ARGUMENT_PACK_ARGS (expression);
19462 int i, len = TREE_VEC_LENGTH (values);
19464 for (i = 0; i < len; ++i)
19465 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
19473 tree type2 = TRAIT_EXPR_TYPE2 (expression);
19474 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
19475 || (type2 ? dependent_type_p (type2) : false));
19479 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19480 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
19483 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19484 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
19488 tree op = TREE_OPERAND (expression, 0);
19489 return (value_dependent_expression_p (op)
19490 || has_value_dependent_address (op));
19495 tree fn = get_callee_fndecl (expression);
19497 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
19499 nargs = call_expr_nargs (expression);
19500 for (i = 0; i < nargs; ++i)
19502 tree op = CALL_EXPR_ARG (expression, i);
19503 /* In a call to a constexpr member function, look through the
19504 implicit ADDR_EXPR on the object argument so that it doesn't
19505 cause the call to be considered value-dependent. We also
19506 look through it in potential_constant_expression. */
19507 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
19508 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
19509 && TREE_CODE (op) == ADDR_EXPR)
19510 op = TREE_OPERAND (op, 0);
19511 if (value_dependent_expression_p (op))
19517 case TEMPLATE_ID_EXPR:
19518 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
19520 return type_dependent_expression_p (expression);
19526 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
19527 if (value_dependent_expression_p (val))
19533 /* Treat a GNU statement expression as dependent to avoid crashing
19534 under fold_non_dependent_expr; it can't be constant. */
19538 /* A constant expression is value-dependent if any subexpression is
19539 value-dependent. */
19540 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
19542 case tcc_reference:
19544 case tcc_comparison:
19546 case tcc_expression:
19549 int i, len = cp_tree_operand_length (expression);
19551 for (i = 0; i < len; i++)
19553 tree t = TREE_OPERAND (expression, i);
19555 /* In some cases, some of the operands may be missing.l
19556 (For example, in the case of PREDECREMENT_EXPR, the
19557 amount to increment by may be missing.) That doesn't
19558 make the expression dependent. */
19559 if (t && value_dependent_expression_p (t))
19570 /* The expression is not value-dependent. */
19574 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
19575 [temp.dep.expr]. Note that an expression with no type is
19576 considered dependent. Other parts of the compiler arrange for an
19577 expression with type-dependent subexpressions to have no type, so
19578 this function doesn't have to be fully recursive. */
19581 type_dependent_expression_p (tree expression)
19583 if (!processing_template_decl)
19586 if (expression == error_mark_node)
19589 /* An unresolved name is always dependent. */
19590 if (TREE_CODE (expression) == IDENTIFIER_NODE
19591 || TREE_CODE (expression) == USING_DECL)
19594 /* Some expression forms are never type-dependent. */
19595 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
19596 || TREE_CODE (expression) == SIZEOF_EXPR
19597 || TREE_CODE (expression) == ALIGNOF_EXPR
19598 || TREE_CODE (expression) == AT_ENCODE_EXPR
19599 || TREE_CODE (expression) == NOEXCEPT_EXPR
19600 || TREE_CODE (expression) == TRAIT_EXPR
19601 || TREE_CODE (expression) == TYPEID_EXPR
19602 || TREE_CODE (expression) == DELETE_EXPR
19603 || TREE_CODE (expression) == VEC_DELETE_EXPR
19604 || TREE_CODE (expression) == THROW_EXPR)
19607 /* The types of these expressions depends only on the type to which
19608 the cast occurs. */
19609 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
19610 || TREE_CODE (expression) == STATIC_CAST_EXPR
19611 || TREE_CODE (expression) == CONST_CAST_EXPR
19612 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
19613 || TREE_CODE (expression) == IMPLICIT_CONV_EXPR
19614 || TREE_CODE (expression) == CAST_EXPR)
19615 return dependent_type_p (TREE_TYPE (expression));
19617 /* The types of these expressions depends only on the type created
19618 by the expression. */
19619 if (TREE_CODE (expression) == NEW_EXPR
19620 || TREE_CODE (expression) == VEC_NEW_EXPR)
19622 /* For NEW_EXPR tree nodes created inside a template, either
19623 the object type itself or a TREE_LIST may appear as the
19625 tree type = TREE_OPERAND (expression, 1);
19626 if (TREE_CODE (type) == TREE_LIST)
19627 /* This is an array type. We need to check array dimensions
19629 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
19630 || value_dependent_expression_p
19631 (TREE_OPERAND (TREE_VALUE (type), 1));
19633 return dependent_type_p (type);
19636 if (TREE_CODE (expression) == SCOPE_REF)
19638 tree scope = TREE_OPERAND (expression, 0);
19639 tree name = TREE_OPERAND (expression, 1);
19641 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
19642 contains an identifier associated by name lookup with one or more
19643 declarations declared with a dependent type, or...a
19644 nested-name-specifier or qualified-id that names a member of an
19645 unknown specialization. */
19646 return (type_dependent_expression_p (name)
19647 || dependent_scope_p (scope));
19650 if (TREE_CODE (expression) == FUNCTION_DECL
19651 && DECL_LANG_SPECIFIC (expression)
19652 && DECL_TEMPLATE_INFO (expression)
19653 && (any_dependent_template_arguments_p
19654 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
19657 if (TREE_CODE (expression) == TEMPLATE_DECL
19658 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
19661 if (TREE_CODE (expression) == STMT_EXPR)
19662 expression = stmt_expr_value_expr (expression);
19664 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
19669 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
19671 if (type_dependent_expression_p (elt))
19677 /* A static data member of the current instantiation with incomplete
19678 array type is type-dependent, as the definition and specializations
19679 can have different bounds. */
19680 if (TREE_CODE (expression) == VAR_DECL
19681 && DECL_CLASS_SCOPE_P (expression)
19682 && dependent_type_p (DECL_CONTEXT (expression))
19683 && VAR_HAD_UNKNOWN_BOUND (expression))
19686 if (TREE_TYPE (expression) == unknown_type_node)
19688 if (TREE_CODE (expression) == ADDR_EXPR)
19689 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
19690 if (TREE_CODE (expression) == COMPONENT_REF
19691 || TREE_CODE (expression) == OFFSET_REF)
19693 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
19695 expression = TREE_OPERAND (expression, 1);
19696 if (TREE_CODE (expression) == IDENTIFIER_NODE)
19699 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
19700 if (TREE_CODE (expression) == SCOPE_REF)
19703 if (BASELINK_P (expression))
19704 expression = BASELINK_FUNCTIONS (expression);
19706 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
19708 if (any_dependent_template_arguments_p
19709 (TREE_OPERAND (expression, 1)))
19711 expression = TREE_OPERAND (expression, 0);
19713 gcc_assert (TREE_CODE (expression) == OVERLOAD
19714 || TREE_CODE (expression) == FUNCTION_DECL);
19718 if (type_dependent_expression_p (OVL_CURRENT (expression)))
19720 expression = OVL_NEXT (expression);
19725 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
19727 return (dependent_type_p (TREE_TYPE (expression)));
19730 /* Like type_dependent_expression_p, but it also works while not processing
19731 a template definition, i.e. during substitution or mangling. */
19734 type_dependent_expression_p_push (tree expr)
19737 ++processing_template_decl;
19738 b = type_dependent_expression_p (expr);
19739 --processing_template_decl;
19743 /* Returns TRUE if ARGS contains a type-dependent expression. */
19746 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
19751 FOR_EACH_VEC_ELT (tree, args, i, arg)
19753 if (type_dependent_expression_p (arg))
19759 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19760 expressions) contains any type-dependent expressions. */
19763 any_type_dependent_elements_p (const_tree list)
19765 for (; list; list = TREE_CHAIN (list))
19766 if (value_dependent_expression_p (TREE_VALUE (list)))
19772 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19773 expressions) contains any value-dependent expressions. */
19776 any_value_dependent_elements_p (const_tree list)
19778 for (; list; list = TREE_CHAIN (list))
19779 if (value_dependent_expression_p (TREE_VALUE (list)))
19785 /* Returns TRUE if the ARG (a template argument) is dependent. */
19788 dependent_template_arg_p (tree arg)
19790 if (!processing_template_decl)
19793 /* Assume a template argument that was wrongly written by the user
19794 is dependent. This is consistent with what
19795 any_dependent_template_arguments_p [that calls this function]
19797 if (!arg || arg == error_mark_node)
19800 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
19801 arg = ARGUMENT_PACK_SELECT_ARG (arg);
19803 if (TREE_CODE (arg) == TEMPLATE_DECL
19804 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19805 return dependent_template_p (arg);
19806 else if (ARGUMENT_PACK_P (arg))
19808 tree args = ARGUMENT_PACK_ARGS (arg);
19809 int i, len = TREE_VEC_LENGTH (args);
19810 for (i = 0; i < len; ++i)
19812 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19818 else if (TYPE_P (arg))
19819 return dependent_type_p (arg);
19821 return (type_dependent_expression_p (arg)
19822 || value_dependent_expression_p (arg));
19825 /* Returns true if ARGS (a collection of template arguments) contains
19826 any types that require structural equality testing. */
19829 any_template_arguments_need_structural_equality_p (tree args)
19836 if (args == error_mark_node)
19839 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19841 tree level = TMPL_ARGS_LEVEL (args, i + 1);
19842 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19844 tree arg = TREE_VEC_ELT (level, j);
19845 tree packed_args = NULL_TREE;
19848 if (ARGUMENT_PACK_P (arg))
19850 /* Look inside the argument pack. */
19851 packed_args = ARGUMENT_PACK_ARGS (arg);
19852 len = TREE_VEC_LENGTH (packed_args);
19855 for (k = 0; k < len; ++k)
19858 arg = TREE_VEC_ELT (packed_args, k);
19860 if (error_operand_p (arg))
19862 else if (TREE_CODE (arg) == TEMPLATE_DECL
19863 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19865 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
19867 else if (!TYPE_P (arg) && TREE_TYPE (arg)
19868 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
19877 /* Returns true if ARGS (a collection of template arguments) contains
19878 any dependent arguments. */
19881 any_dependent_template_arguments_p (const_tree args)
19888 if (args == error_mark_node)
19891 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19893 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
19894 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19895 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
19902 /* Returns TRUE if the template TMPL is dependent. */
19905 dependent_template_p (tree tmpl)
19907 if (TREE_CODE (tmpl) == OVERLOAD)
19911 if (dependent_template_p (OVL_CURRENT (tmpl)))
19913 tmpl = OVL_NEXT (tmpl);
19918 /* Template template parameters are dependent. */
19919 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
19920 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
19922 /* So are names that have not been looked up. */
19923 if (TREE_CODE (tmpl) == SCOPE_REF
19924 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
19926 /* So are member templates of dependent classes. */
19927 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
19928 return dependent_type_p (DECL_CONTEXT (tmpl));
19932 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
19935 dependent_template_id_p (tree tmpl, tree args)
19937 return (dependent_template_p (tmpl)
19938 || any_dependent_template_arguments_p (args));
19941 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
19945 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
19949 if (!processing_template_decl)
19952 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
19954 tree decl = TREE_VEC_ELT (declv, i);
19955 tree init = TREE_VEC_ELT (initv, i);
19956 tree cond = TREE_VEC_ELT (condv, i);
19957 tree incr = TREE_VEC_ELT (incrv, i);
19959 if (type_dependent_expression_p (decl))
19962 if (init && type_dependent_expression_p (init))
19965 if (type_dependent_expression_p (cond))
19968 if (COMPARISON_CLASS_P (cond)
19969 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
19970 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
19973 if (TREE_CODE (incr) == MODOP_EXPR)
19975 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
19976 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
19979 else if (type_dependent_expression_p (incr))
19981 else if (TREE_CODE (incr) == MODIFY_EXPR)
19983 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
19985 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
19987 tree t = TREE_OPERAND (incr, 1);
19988 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
19989 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
19998 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
19999 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
20000 no such TYPE can be found. Note that this function peers inside
20001 uninstantiated templates and therefore should be used only in
20002 extremely limited situations. ONLY_CURRENT_P restricts this
20003 peering to the currently open classes hierarchy (which is required
20004 when comparing types). */
20007 resolve_typename_type (tree type, bool only_current_p)
20016 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
20018 scope = TYPE_CONTEXT (type);
20019 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
20020 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
20021 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
20022 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
20023 identifier of the TYPENAME_TYPE anymore.
20024 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
20025 TYPENAME_TYPE instead, we avoid messing up with a possible
20026 typedef variant case. */
20027 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
20029 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
20030 it first before we can figure out what NAME refers to. */
20031 if (TREE_CODE (scope) == TYPENAME_TYPE)
20032 scope = resolve_typename_type (scope, only_current_p);
20033 /* If we don't know what SCOPE refers to, then we cannot resolve the
20035 if (TREE_CODE (scope) == TYPENAME_TYPE)
20037 /* If the SCOPE is a template type parameter, we have no way of
20038 resolving the name. */
20039 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
20041 /* If the SCOPE is not the current instantiation, there's no reason
20042 to look inside it. */
20043 if (only_current_p && !currently_open_class (scope))
20045 /* If this is a typedef, we don't want to look inside (c++/11987). */
20046 if (typedef_variant_p (type))
20048 /* If SCOPE isn't the template itself, it will not have a valid
20049 TYPE_FIELDS list. */
20050 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
20051 /* scope is either the template itself or a compatible instantiation
20052 like X<T>, so look up the name in the original template. */
20053 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
20055 /* scope is a partial instantiation, so we can't do the lookup or we
20056 will lose the template arguments. */
20058 /* Enter the SCOPE so that name lookup will be resolved as if we
20059 were in the class definition. In particular, SCOPE will no
20060 longer be considered a dependent type. */
20061 pushed_scope = push_scope (scope);
20062 /* Look up the declaration. */
20063 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true,
20064 tf_warning_or_error);
20066 result = NULL_TREE;
20068 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
20069 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
20072 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
20073 && TREE_CODE (decl) == TYPE_DECL)
20075 result = TREE_TYPE (decl);
20076 if (result == error_mark_node)
20077 result = NULL_TREE;
20079 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
20080 && DECL_CLASS_TEMPLATE_P (decl))
20084 /* Obtain the template and the arguments. */
20085 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
20086 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
20087 /* Instantiate the template. */
20088 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
20089 /*entering_scope=*/0,
20090 tf_error | tf_user);
20091 if (result == error_mark_node)
20092 result = NULL_TREE;
20095 /* Leave the SCOPE. */
20097 pop_scope (pushed_scope);
20099 /* If we failed to resolve it, return the original typename. */
20103 /* If lookup found a typename type, resolve that too. */
20104 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
20106 /* Ill-formed programs can cause infinite recursion here, so we
20107 must catch that. */
20108 TYPENAME_IS_RESOLVING_P (type) = 1;
20109 result = resolve_typename_type (result, only_current_p);
20110 TYPENAME_IS_RESOLVING_P (type) = 0;
20113 /* Qualify the resulting type. */
20114 quals = cp_type_quals (type);
20116 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
20121 /* EXPR is an expression which is not type-dependent. Return a proxy
20122 for EXPR that can be used to compute the types of larger
20123 expressions containing EXPR. */
20126 build_non_dependent_expr (tree expr)
20130 #ifdef ENABLE_CHECKING
20131 /* Try to get a constant value for all non-type-dependent expressions in
20132 order to expose bugs in *_dependent_expression_p and constexpr. */
20133 if (cxx_dialect >= cxx0x)
20134 maybe_constant_value (fold_non_dependent_expr_sfinae (expr, tf_none));
20137 /* Preserve OVERLOADs; the functions must be available to resolve
20140 if (TREE_CODE (inner_expr) == STMT_EXPR)
20141 inner_expr = stmt_expr_value_expr (inner_expr);
20142 if (TREE_CODE (inner_expr) == ADDR_EXPR)
20143 inner_expr = TREE_OPERAND (inner_expr, 0);
20144 if (TREE_CODE (inner_expr) == COMPONENT_REF)
20145 inner_expr = TREE_OPERAND (inner_expr, 1);
20146 if (is_overloaded_fn (inner_expr)
20147 || TREE_CODE (inner_expr) == OFFSET_REF)
20149 /* There is no need to return a proxy for a variable. */
20150 if (TREE_CODE (expr) == VAR_DECL)
20152 /* Preserve string constants; conversions from string constants to
20153 "char *" are allowed, even though normally a "const char *"
20154 cannot be used to initialize a "char *". */
20155 if (TREE_CODE (expr) == STRING_CST)
20157 /* Preserve arithmetic constants, as an optimization -- there is no
20158 reason to create a new node. */
20159 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
20161 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
20162 There is at least one place where we want to know that a
20163 particular expression is a throw-expression: when checking a ?:
20164 expression, there are special rules if the second or third
20165 argument is a throw-expression. */
20166 if (TREE_CODE (expr) == THROW_EXPR)
20169 /* Don't wrap an initializer list, we need to be able to look inside. */
20170 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
20173 if (TREE_CODE (expr) == COND_EXPR)
20174 return build3 (COND_EXPR,
20176 TREE_OPERAND (expr, 0),
20177 (TREE_OPERAND (expr, 1)
20178 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
20179 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
20180 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
20181 if (TREE_CODE (expr) == COMPOUND_EXPR
20182 && !COMPOUND_EXPR_OVERLOADED (expr))
20183 return build2 (COMPOUND_EXPR,
20185 TREE_OPERAND (expr, 0),
20186 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
20188 /* If the type is unknown, it can't really be non-dependent */
20189 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
20191 /* Otherwise, build a NON_DEPENDENT_EXPR. */
20192 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
20195 /* ARGS is a vector of expressions as arguments to a function call.
20196 Replace the arguments with equivalent non-dependent expressions.
20197 This modifies ARGS in place. */
20200 make_args_non_dependent (VEC(tree,gc) *args)
20205 FOR_EACH_VEC_ELT (tree, args, ix, arg)
20207 tree newarg = build_non_dependent_expr (arg);
20209 VEC_replace (tree, args, ix, newarg);
20213 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
20214 with a level one deeper than the actual template parms. */
20219 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
20220 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
20221 TYPE_DECL, get_identifier ("auto"), au);
20222 TYPE_STUB_DECL (au) = TYPE_NAME (au);
20223 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
20224 (0, processing_template_decl + 1, processing_template_decl + 1,
20225 0, TYPE_NAME (au), NULL_TREE);
20226 TYPE_CANONICAL (au) = canonical_type_parameter (au);
20227 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
20228 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
20233 /* Given type ARG, return std::initializer_list<ARG>. */
20238 tree std_init_list = namespace_binding
20239 (get_identifier ("initializer_list"), std_node);
20241 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
20243 error ("deducing from brace-enclosed initializer list requires "
20244 "#include <initializer_list>");
20245 return error_mark_node;
20247 argvec = make_tree_vec (1);
20248 TREE_VEC_ELT (argvec, 0) = arg;
20249 return lookup_template_class (std_init_list, argvec, NULL_TREE,
20250 NULL_TREE, 0, tf_warning_or_error);
20253 /* Replace auto in TYPE with std::initializer_list<auto>. */
20256 listify_autos (tree type, tree auto_node)
20258 tree init_auto = listify (auto_node);
20259 tree argvec = make_tree_vec (1);
20260 TREE_VEC_ELT (argvec, 0) = init_auto;
20261 if (processing_template_decl)
20262 argvec = add_to_template_args (current_template_args (), argvec);
20263 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20266 /* walk_tree helper for do_auto_deduction. */
20269 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
20272 /* Is this a variable with the type we're looking for? */
20274 && TREE_TYPE (*tp) == type)
20280 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
20281 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
20284 do_auto_deduction (tree type, tree init, tree auto_node)
20286 tree parms, tparms, targs;
20291 if (processing_template_decl
20292 && (TREE_TYPE (init) == NULL_TREE
20293 || BRACE_ENCLOSED_INITIALIZER_P (init)))
20294 /* Not enough information to try this yet. */
20297 /* The name of the object being declared shall not appear in the
20298 initializer expression. */
20299 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
20302 error ("variable %q#D with %<auto%> type used in its own "
20303 "initializer", decl);
20304 return error_mark_node;
20307 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
20308 with either a new invented type template parameter U or, if the
20309 initializer is a braced-init-list (8.5.4), with
20310 std::initializer_list<U>. */
20311 if (BRACE_ENCLOSED_INITIALIZER_P (init))
20312 type = listify_autos (type, auto_node);
20314 init = resolve_nondeduced_context (init);
20316 parms = build_tree_list (NULL_TREE, type);
20318 tparms = make_tree_vec (1);
20319 targs = make_tree_vec (1);
20320 TREE_VEC_ELT (tparms, 0)
20321 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
20322 val = type_unification_real (tparms, targs, parms, args, 1, 0,
20323 DEDUCE_CALL, LOOKUP_NORMAL,
20324 /*explain_p=*/false);
20327 if (processing_template_decl)
20328 /* Try again at instantiation time. */
20330 if (type && type != error_mark_node)
20331 /* If type is error_mark_node a diagnostic must have been
20332 emitted by now. Also, having a mention to '<type error>'
20333 in the diagnostic is not really useful to the user. */
20334 error ("unable to deduce %qT from %qE", type, init);
20335 return error_mark_node;
20338 /* If the list of declarators contains more than one declarator, the type
20339 of each declared variable is determined as described above. If the
20340 type deduced for the template parameter U is not the same in each
20341 deduction, the program is ill-formed. */
20342 if (TREE_TYPE (auto_node)
20343 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
20345 error ("inconsistent deduction for %qT: %qT and then %qT",
20346 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
20347 return error_mark_node;
20349 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
20351 if (processing_template_decl)
20352 targs = add_to_template_args (current_template_args (), targs);
20353 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
20356 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
20360 splice_late_return_type (tree type, tree late_return_type)
20364 if (late_return_type == NULL_TREE)
20366 argvec = make_tree_vec (1);
20367 TREE_VEC_ELT (argvec, 0) = late_return_type;
20368 if (processing_template_parmlist)
20369 /* For a late-specified return type in a template type-parameter, we
20370 need to add a dummy argument level for its parmlist. */
20371 argvec = add_to_template_args
20372 (make_tree_vec (processing_template_parmlist), argvec);
20373 if (current_template_parms)
20374 argvec = add_to_template_args (current_template_args (), argvec);
20375 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20378 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
20381 is_auto (const_tree type)
20383 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
20384 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
20390 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
20391 appear as a type-specifier for the declaration in question, we don't
20392 have to look through the whole type. */
20395 type_uses_auto (tree type)
20397 enum tree_code code;
20398 if (is_auto (type))
20401 code = TREE_CODE (type);
20403 if (code == POINTER_TYPE || code == REFERENCE_TYPE
20404 || code == OFFSET_TYPE || code == FUNCTION_TYPE
20405 || code == METHOD_TYPE || code == ARRAY_TYPE)
20406 return type_uses_auto (TREE_TYPE (type));
20408 if (TYPE_PTRMEMFUNC_P (type))
20409 return type_uses_auto (TREE_TYPE (TREE_TYPE
20410 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
20415 /* For a given template T, return the vector of typedefs referenced
20416 in T for which access check is needed at T instantiation time.
20417 T is either a FUNCTION_DECL or a RECORD_TYPE.
20418 Those typedefs were added to T by the function
20419 append_type_to_template_for_access_check. */
20421 VEC(qualified_typedef_usage_t,gc)*
20422 get_types_needing_access_check (tree t)
20425 VEC(qualified_typedef_usage_t,gc) *result = NULL;
20427 if (!t || t == error_mark_node)
20430 if (!(ti = get_template_info (t)))
20433 if (CLASS_TYPE_P (t)
20434 || TREE_CODE (t) == FUNCTION_DECL)
20436 if (!TI_TEMPLATE (ti))
20439 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
20445 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
20446 tied to T. That list of typedefs will be access checked at
20447 T instantiation time.
20448 T is either a FUNCTION_DECL or a RECORD_TYPE.
20449 TYPE_DECL is a TYPE_DECL node representing a typedef.
20450 SCOPE is the scope through which TYPE_DECL is accessed.
20451 LOCATION is the location of the usage point of TYPE_DECL.
20453 This function is a subroutine of
20454 append_type_to_template_for_access_check. */
20457 append_type_to_template_for_access_check_1 (tree t,
20460 location_t location)
20462 qualified_typedef_usage_t typedef_usage;
20465 if (!t || t == error_mark_node)
20468 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
20469 || CLASS_TYPE_P (t))
20471 && TREE_CODE (type_decl) == TYPE_DECL
20474 if (!(ti = get_template_info (t)))
20477 gcc_assert (TI_TEMPLATE (ti));
20479 typedef_usage.typedef_decl = type_decl;
20480 typedef_usage.context = scope;
20481 typedef_usage.locus = location;
20483 VEC_safe_push (qualified_typedef_usage_t, gc,
20484 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
20488 /* Append TYPE_DECL to the template TEMPL.
20489 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
20490 At TEMPL instanciation time, TYPE_DECL will be checked to see
20491 if it can be accessed through SCOPE.
20492 LOCATION is the location of the usage point of TYPE_DECL.
20494 e.g. consider the following code snippet:
20501 template<class U> struct S
20503 C::myint mi; // <-- usage point of the typedef C::myint
20508 At S<char> instantiation time, we need to check the access of C::myint
20509 In other words, we need to check the access of the myint typedef through
20510 the C scope. For that purpose, this function will add the myint typedef
20511 and the scope C through which its being accessed to a list of typedefs
20512 tied to the template S. That list will be walked at template instantiation
20513 time and access check performed on each typedefs it contains.
20514 Note that this particular code snippet should yield an error because
20515 myint is private to C. */
20518 append_type_to_template_for_access_check (tree templ,
20521 location_t location)
20523 qualified_typedef_usage_t *iter;
20526 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
20528 /* Make sure we don't append the type to the template twice. */
20529 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
20530 get_types_needing_access_check (templ),
20532 if (iter->typedef_decl == type_decl && scope == iter->context)
20535 append_type_to_template_for_access_check_1 (templ, type_decl,
20539 /* Set up the hash tables for template instantiations. */
20542 init_template_processing (void)
20544 decl_specializations = htab_create_ggc (37,
20545 hash_specialization,
20546 eq_specializations,
20548 type_specializations = htab_create_ggc (37,
20549 hash_specialization,
20550 eq_specializations,
20554 /* Print stats about the template hash tables for -fstats. */
20557 print_template_statistics (void)
20559 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
20560 "%f collisions\n", (long) htab_size (decl_specializations),
20561 (long) htab_elements (decl_specializations),
20562 htab_collisions (decl_specializations));
20563 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
20564 "%f collisions\n", (long) htab_size (type_specializations),
20565 (long) htab_elements (type_specializations),
20566 htab_collisions (type_specializations));
20569 #include "gt-cp-pt.h"