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, 2012
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;
1865 /* In case of explicit specialization, we need to check if
1866 the number of template headers appearing in the specialization
1867 is correct. This is usually done in check_explicit_specialization,
1868 but the check done there cannot be exhaustive when specializing
1869 member functions. Consider the following code:
1871 template <> void A<int>::f(int);
1872 template <> template <> void A<int>::f(int);
1874 Assuming that A<int> is not itself an explicit specialization
1875 already, the first line specializes "f" which is a non-template
1876 member function, whilst the second line specializes "f" which
1877 is a template member function. So both lines are syntactically
1878 correct, and check_explicit_specialization does not reject
1881 Here, we can do better, as we are matching the specialization
1882 against the declarations. We count the number of template
1883 headers, and we check if they match TEMPLATE_COUNT + 1
1884 (TEMPLATE_COUNT is the number of qualifying template classes,
1885 plus there must be another header for the member template
1888 Notice that if header_count is zero, this is not a
1889 specialization but rather a template instantiation, so there
1890 is no check we can perform here. */
1891 if (header_count && header_count != template_count + 1)
1894 /* Check that the number of template arguments at the
1895 innermost level for DECL is the same as for FN. */
1896 if (current_binding_level->kind == sk_template_parms
1897 && !current_binding_level->explicit_spec_p
1898 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1899 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1900 (current_template_parms))))
1903 /* DECL might be a specialization of FN. */
1904 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1905 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1907 /* For a non-static member function, we need to make sure
1908 that the const qualification is the same. Since
1909 get_bindings does not try to merge the "this" parameter,
1910 we must do the comparison explicitly. */
1911 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1912 && !same_type_p (TREE_VALUE (fn_arg_types),
1913 TREE_VALUE (decl_arg_types)))
1916 /* Skip the "this" parameter and, for constructors of
1917 classes with virtual bases, the VTT parameter. A
1918 full specialization of a constructor will have a VTT
1919 parameter, but a template never will. */
1921 = skip_artificial_parms_for (decl, decl_arg_types);
1923 = skip_artificial_parms_for (fn, fn_arg_types);
1925 /* Check that the number of function parameters matches.
1927 template <class T> void f(int i = 0);
1928 template <> void f<int>();
1929 The specialization f<int> is invalid but is not caught
1930 by get_bindings below. */
1931 if (cxx_dialect < cxx11
1932 && list_length (fn_arg_types) != list_length (decl_arg_types))
1935 /* Function templates cannot be specializations; there are
1936 no partial specializations of functions. Therefore, if
1937 the type of DECL does not match FN, there is no
1939 if (tsk == tsk_template)
1941 if (compparms (fn_arg_types, decl_arg_types))
1942 candidates = tree_cons (NULL_TREE, fn, candidates);
1946 /* See whether this function might be a specialization of this
1948 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1951 /* We cannot deduce template arguments that when used to
1952 specialize TMPL will produce DECL. */
1955 if (cxx_dialect >= cxx11)
1957 /* Make sure that the deduced arguments actually work. */
1958 insttype = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE);
1959 if (insttype == error_mark_node)
1962 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (insttype));
1963 if (!compparms (fn_arg_types, decl_arg_types))
1967 /* Save this template, and the arguments deduced. */
1968 templates = tree_cons (targs, fn, templates);
1970 else if (need_member_template)
1971 /* FN is an ordinary member function, and we need a
1972 specialization of a member template. */
1974 else if (TREE_CODE (fn) != FUNCTION_DECL)
1975 /* We can get IDENTIFIER_NODEs here in certain erroneous
1978 else if (!DECL_FUNCTION_MEMBER_P (fn))
1979 /* This is just an ordinary non-member function. Nothing can
1980 be a specialization of that. */
1982 else if (DECL_ARTIFICIAL (fn))
1983 /* Cannot specialize functions that are created implicitly. */
1987 tree decl_arg_types;
1989 /* This is an ordinary member function. However, since
1990 we're here, we can assume it's enclosing class is a
1991 template class. For example,
1993 template <typename T> struct S { void f(); };
1994 template <> void S<int>::f() {}
1996 Here, S<int>::f is a non-template, but S<int> is a
1997 template class. If FN has the same type as DECL, we
1998 might be in business. */
2000 if (!DECL_TEMPLATE_INFO (fn))
2001 /* Its enclosing class is an explicit specialization
2002 of a template class. This is not a candidate. */
2005 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
2006 TREE_TYPE (TREE_TYPE (fn))))
2007 /* The return types differ. */
2010 /* Adjust the type of DECL in case FN is a static member. */
2011 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
2012 if (DECL_STATIC_FUNCTION_P (fn)
2013 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2014 decl_arg_types = TREE_CHAIN (decl_arg_types);
2016 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
2019 candidates = tree_cons (NULL_TREE, fn, candidates);
2023 if (templates && TREE_CHAIN (templates))
2029 It is possible for a specialization with a given function
2030 signature to be instantiated from more than one function
2031 template. In such cases, explicit specification of the
2032 template arguments must be used to uniquely identify the
2033 function template specialization being specialized.
2035 Note that here, there's no suggestion that we're supposed to
2036 determine which of the candidate templates is most
2037 specialized. However, we, also have:
2041 Partial ordering of overloaded function template
2042 declarations is used in the following contexts to select
2043 the function template to which a function template
2044 specialization refers:
2046 -- when an explicit specialization refers to a function
2049 So, we do use the partial ordering rules, at least for now.
2050 This extension can only serve to make invalid programs valid,
2051 so it's safe. And, there is strong anecdotal evidence that
2052 the committee intended the partial ordering rules to apply;
2053 the EDG front end has that behavior, and John Spicer claims
2054 that the committee simply forgot to delete the wording in
2055 [temp.expl.spec]. */
2056 tree tmpl = most_specialized_instantiation (templates);
2057 if (tmpl != error_mark_node)
2060 TREE_CHAIN (templates) = NULL_TREE;
2064 if (templates == NULL_TREE && candidates == NULL_TREE)
2066 error ("template-id %qD for %q+D does not match any template "
2067 "declaration", template_id, decl);
2068 if (header_count && header_count != template_count + 1)
2069 inform (input_location, "saw %d %<template<>%>, need %d for "
2070 "specializing a member function template",
2071 header_count, template_count + 1);
2072 return error_mark_node;
2074 else if ((templates && TREE_CHAIN (templates))
2075 || (candidates && TREE_CHAIN (candidates))
2076 || (templates && candidates))
2078 error ("ambiguous template specialization %qD for %q+D",
2080 candidates = chainon (candidates, templates);
2081 print_candidates (candidates);
2082 return error_mark_node;
2085 /* We have one, and exactly one, match. */
2088 tree fn = TREE_VALUE (candidates);
2089 *targs_out = copy_node (DECL_TI_ARGS (fn));
2090 /* DECL is a re-declaration or partial instantiation of a template
2092 if (TREE_CODE (fn) == TEMPLATE_DECL)
2094 /* It was a specialization of an ordinary member function in a
2096 return DECL_TI_TEMPLATE (fn);
2099 /* It was a specialization of a template. */
2100 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2101 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2103 *targs_out = copy_node (targs);
2104 SET_TMPL_ARGS_LEVEL (*targs_out,
2105 TMPL_ARGS_DEPTH (*targs_out),
2106 TREE_PURPOSE (templates));
2109 *targs_out = TREE_PURPOSE (templates);
2110 return TREE_VALUE (templates);
2113 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2114 but with the default argument values filled in from those in the
2118 copy_default_args_to_explicit_spec_1 (tree spec_types,
2121 tree new_spec_types;
2126 if (spec_types == void_list_node)
2127 return void_list_node;
2129 /* Substitute into the rest of the list. */
2131 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2132 TREE_CHAIN (tmpl_types));
2134 /* Add the default argument for this parameter. */
2135 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2136 TREE_VALUE (spec_types),
2140 /* DECL is an explicit specialization. Replicate default arguments
2141 from the template it specializes. (That way, code like:
2143 template <class T> void f(T = 3);
2144 template <> void f(double);
2147 works, as required.) An alternative approach would be to look up
2148 the correct default arguments at the call-site, but this approach
2149 is consistent with how implicit instantiations are handled. */
2152 copy_default_args_to_explicit_spec (tree decl)
2157 tree new_spec_types;
2161 tree object_type = NULL_TREE;
2162 tree in_charge = NULL_TREE;
2163 tree vtt = NULL_TREE;
2165 /* See if there's anything we need to do. */
2166 tmpl = DECL_TI_TEMPLATE (decl);
2167 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2168 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2169 if (TREE_PURPOSE (t))
2174 old_type = TREE_TYPE (decl);
2175 spec_types = TYPE_ARG_TYPES (old_type);
2177 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2179 /* Remove the this pointer, but remember the object's type for
2181 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2182 spec_types = TREE_CHAIN (spec_types);
2183 tmpl_types = TREE_CHAIN (tmpl_types);
2185 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2187 /* DECL may contain more parameters than TMPL due to the extra
2188 in-charge parameter in constructors and destructors. */
2189 in_charge = spec_types;
2190 spec_types = TREE_CHAIN (spec_types);
2192 if (DECL_HAS_VTT_PARM_P (decl))
2195 spec_types = TREE_CHAIN (spec_types);
2199 /* Compute the merged default arguments. */
2201 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2203 /* Compute the new FUNCTION_TYPE. */
2207 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2212 /* Put the in-charge parameter back. */
2213 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2214 TREE_VALUE (in_charge),
2217 new_type = build_method_type_directly (object_type,
2218 TREE_TYPE (old_type),
2222 new_type = build_function_type (TREE_TYPE (old_type),
2224 new_type = cp_build_type_attribute_variant (new_type,
2225 TYPE_ATTRIBUTES (old_type));
2226 new_type = build_exception_variant (new_type,
2227 TYPE_RAISES_EXCEPTIONS (old_type));
2228 TREE_TYPE (decl) = new_type;
2231 /* Check to see if the function just declared, as indicated in
2232 DECLARATOR, and in DECL, is a specialization of a function
2233 template. We may also discover that the declaration is an explicit
2234 instantiation at this point.
2236 Returns DECL, or an equivalent declaration that should be used
2237 instead if all goes well. Issues an error message if something is
2238 amiss. Returns error_mark_node if the error is not easily
2241 FLAGS is a bitmask consisting of the following flags:
2243 2: The function has a definition.
2244 4: The function is a friend.
2246 The TEMPLATE_COUNT is the number of references to qualifying
2247 template classes that appeared in the name of the function. For
2250 template <class T> struct S { void f(); };
2253 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2254 classes are not counted in the TEMPLATE_COUNT, so that in
2256 template <class T> struct S {};
2257 template <> struct S<int> { void f(); }
2258 template <> void S<int>::f();
2260 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2261 invalid; there should be no template <>.)
2263 If the function is a specialization, it is marked as such via
2264 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2265 is set up correctly, and it is added to the list of specializations
2266 for that template. */
2269 check_explicit_specialization (tree declarator,
2274 int have_def = flags & 2;
2275 int is_friend = flags & 4;
2276 int specialization = 0;
2277 int explicit_instantiation = 0;
2278 int member_specialization = 0;
2279 tree ctype = DECL_CLASS_CONTEXT (decl);
2280 tree dname = DECL_NAME (decl);
2285 if (!processing_specialization)
2288 tsk = tsk_excessive_parms;
2291 tsk = current_tmpl_spec_kind (template_count);
2296 if (processing_specialization)
2299 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2301 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2304 /* This could be something like:
2306 template <class T> void f(T);
2307 class S { friend void f<>(int); } */
2311 /* This case handles bogus declarations like template <>
2312 template <class T> void f<int>(); */
2314 error ("template-id %qD in declaration of primary template",
2321 case tsk_invalid_member_spec:
2322 /* The error has already been reported in
2323 check_specialization_scope. */
2324 return error_mark_node;
2326 case tsk_invalid_expl_inst:
2327 error ("template parameter list used in explicit instantiation");
2333 error ("definition provided for explicit instantiation");
2335 explicit_instantiation = 1;
2338 case tsk_excessive_parms:
2339 case tsk_insufficient_parms:
2340 if (tsk == tsk_excessive_parms)
2341 error ("too many template parameter lists in declaration of %qD",
2343 else if (template_header_count)
2344 error("too few template parameter lists in declaration of %qD", decl);
2346 error("explicit specialization of %qD must be introduced by "
2347 "%<template <>%>", decl);
2351 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2353 member_specialization = 1;
2359 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2361 /* This case handles bogus declarations like template <>
2362 template <class T> void f<int>(); */
2364 if (uses_template_parms (declarator))
2365 error ("function template partial specialization %qD "
2366 "is not allowed", declarator);
2368 error ("template-id %qD in declaration of primary template",
2373 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2374 /* This is a specialization of a member template, without
2375 specialization the containing class. Something like:
2377 template <class T> struct S {
2378 template <class U> void f (U);
2380 template <> template <class U> void S<int>::f(U) {}
2382 That's a specialization -- but of the entire template. */
2390 if (specialization || member_specialization)
2392 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2393 for (; t; t = TREE_CHAIN (t))
2394 if (TREE_PURPOSE (t))
2396 permerror (input_location,
2397 "default argument specified in explicit specialization");
2402 if (specialization || member_specialization || explicit_instantiation)
2404 tree tmpl = NULL_TREE;
2405 tree targs = NULL_TREE;
2407 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2408 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2412 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2417 /* If there is no class context, the explicit instantiation
2418 must be at namespace scope. */
2419 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2421 /* Find the namespace binding, using the declaration
2423 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2425 if (fns == error_mark_node || !is_overloaded_fn (fns))
2427 error ("%qD is not a template function", dname);
2428 fns = error_mark_node;
2432 tree fn = OVL_CURRENT (fns);
2433 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2434 CP_DECL_CONTEXT (fn)))
2435 error ("%qD is not declared in %qD",
2436 decl, current_namespace);
2440 declarator = lookup_template_function (fns, NULL_TREE);
2443 if (declarator == error_mark_node)
2444 return error_mark_node;
2446 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2448 if (!explicit_instantiation)
2449 /* A specialization in class scope. This is invalid,
2450 but the error will already have been flagged by
2451 check_specialization_scope. */
2452 return error_mark_node;
2455 /* It's not valid to write an explicit instantiation in
2458 class C { template void f(); }
2460 This case is caught by the parser. However, on
2463 template class C { void f(); };
2465 (which is invalid) we can get here. The error will be
2472 else if (ctype != NULL_TREE
2473 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2476 /* Find the list of functions in ctype that have the same
2477 name as the declared function. */
2478 tree name = TREE_OPERAND (declarator, 0);
2479 tree fns = NULL_TREE;
2482 if (constructor_name_p (name, ctype))
2484 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2486 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2487 : !CLASSTYPE_DESTRUCTORS (ctype))
2489 /* From [temp.expl.spec]:
2491 If such an explicit specialization for the member
2492 of a class template names an implicitly-declared
2493 special member function (clause _special_), the
2494 program is ill-formed.
2496 Similar language is found in [temp.explicit]. */
2497 error ("specialization of implicitly-declared special member function");
2498 return error_mark_node;
2501 name = is_constructor ? ctor_identifier : dtor_identifier;
2504 if (!DECL_CONV_FN_P (decl))
2506 idx = lookup_fnfields_1 (ctype, name);
2508 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2512 VEC(tree,gc) *methods;
2515 /* For a type-conversion operator, we cannot do a
2516 name-based lookup. We might be looking for `operator
2517 int' which will be a specialization of `operator T'.
2518 So, we find *all* the conversion operators, and then
2519 select from them. */
2522 methods = CLASSTYPE_METHOD_VEC (ctype);
2524 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2525 VEC_iterate (tree, methods, idx, ovl);
2528 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2529 /* There are no more conversion functions. */
2532 /* Glue all these conversion functions together
2533 with those we already have. */
2534 for (; ovl; ovl = OVL_NEXT (ovl))
2535 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2539 if (fns == NULL_TREE)
2541 error ("no member function %qD declared in %qT", name, ctype);
2542 return error_mark_node;
2545 TREE_OPERAND (declarator, 0) = fns;
2548 /* Figure out what exactly is being specialized at this point.
2549 Note that for an explicit instantiation, even one for a
2550 member function, we cannot tell apriori whether the
2551 instantiation is for a member template, or just a member
2552 function of a template class. Even if a member template is
2553 being instantiated, the member template arguments may be
2554 elided if they can be deduced from the rest of the
2556 tmpl = determine_specialization (declarator, decl,
2558 member_specialization,
2562 if (!tmpl || tmpl == error_mark_node)
2563 /* We couldn't figure out what this declaration was
2565 return error_mark_node;
2568 tree gen_tmpl = most_general_template (tmpl);
2570 if (explicit_instantiation)
2572 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2573 is done by do_decl_instantiation later. */
2575 int arg_depth = TMPL_ARGS_DEPTH (targs);
2576 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2578 if (arg_depth > parm_depth)
2580 /* If TMPL is not the most general template (for
2581 example, if TMPL is a friend template that is
2582 injected into namespace scope), then there will
2583 be too many levels of TARGS. Remove some of them
2588 new_targs = make_tree_vec (parm_depth);
2589 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2590 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2591 = TREE_VEC_ELT (targs, i);
2595 return instantiate_template (tmpl, targs, tf_error);
2598 /* If we thought that the DECL was a member function, but it
2599 turns out to be specializing a static member function,
2600 make DECL a static member function as well. */
2601 if (DECL_STATIC_FUNCTION_P (tmpl)
2602 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2603 revert_static_member_fn (decl);
2605 /* If this is a specialization of a member template of a
2606 template class, we want to return the TEMPLATE_DECL, not
2607 the specialization of it. */
2608 if (tsk == tsk_template)
2610 tree result = DECL_TEMPLATE_RESULT (tmpl);
2611 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2612 DECL_INITIAL (result) = NULL_TREE;
2616 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2617 DECL_SOURCE_LOCATION (result)
2618 = DECL_SOURCE_LOCATION (decl);
2619 /* We want to use the argument list specified in the
2620 definition, not in the original declaration. */
2621 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2622 for (parm = DECL_ARGUMENTS (result); parm;
2623 parm = DECL_CHAIN (parm))
2624 DECL_CONTEXT (parm) = result;
2626 return register_specialization (tmpl, gen_tmpl, targs,
2630 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2631 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2633 /* Inherit default function arguments from the template
2634 DECL is specializing. */
2635 copy_default_args_to_explicit_spec (decl);
2637 /* This specialization has the same protection as the
2638 template it specializes. */
2639 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2640 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2642 /* 7.1.1-1 [dcl.stc]
2644 A storage-class-specifier shall not be specified in an
2645 explicit specialization...
2647 The parser rejects these, so unless action is taken here,
2648 explicit function specializations will always appear with
2651 The action recommended by the C++ CWG in response to C++
2652 defect report 605 is to make the storage class and linkage
2653 of the explicit specialization match the templated function:
2655 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2657 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2659 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2660 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2662 /* This specialization has the same linkage and visibility as
2663 the function template it specializes. */
2664 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2665 if (! TREE_PUBLIC (decl))
2667 DECL_INTERFACE_KNOWN (decl) = 1;
2668 DECL_NOT_REALLY_EXTERN (decl) = 1;
2670 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2671 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2673 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2674 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2678 /* If DECL is a friend declaration, declared using an
2679 unqualified name, the namespace associated with DECL may
2680 have been set incorrectly. For example, in:
2682 template <typename T> void f(T);
2684 struct S { friend void f<int>(int); }
2687 we will have set the DECL_CONTEXT for the friend
2688 declaration to N, rather than to the global namespace. */
2689 if (DECL_NAMESPACE_SCOPE_P (decl))
2690 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2692 if (is_friend && !have_def)
2693 /* This is not really a declaration of a specialization.
2694 It's just the name of an instantiation. But, it's not
2695 a request for an instantiation, either. */
2696 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2697 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2698 /* This is indeed a specialization. In case of constructors
2699 and destructors, we need in-charge and not-in-charge
2700 versions in V3 ABI. */
2701 clone_function_decl (decl, /*update_method_vec_p=*/0);
2703 /* Register this specialization so that we can find it
2705 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2712 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2713 parameters. These are represented in the same format used for
2714 DECL_TEMPLATE_PARMS. */
2717 comp_template_parms (const_tree parms1, const_tree parms2)
2722 if (parms1 == parms2)
2725 for (p1 = parms1, p2 = parms2;
2726 p1 != NULL_TREE && p2 != NULL_TREE;
2727 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2729 tree t1 = TREE_VALUE (p1);
2730 tree t2 = TREE_VALUE (p2);
2733 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2734 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2736 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2739 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2741 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2742 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2744 /* If either of the template parameters are invalid, assume
2745 they match for the sake of error recovery. */
2746 if (parm1 == error_mark_node || parm2 == error_mark_node)
2749 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2752 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2753 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2754 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2756 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2761 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2762 /* One set of parameters has more parameters lists than the
2769 /* Determine whether PARM is a parameter pack. */
2772 template_parameter_pack_p (const_tree parm)
2774 /* Determine if we have a non-type template parameter pack. */
2775 if (TREE_CODE (parm) == PARM_DECL)
2776 return (DECL_TEMPLATE_PARM_P (parm)
2777 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2778 if (TREE_CODE (parm) == TEMPLATE_PARM_INDEX)
2779 return TEMPLATE_PARM_PARAMETER_PACK (parm);
2781 /* If this is a list of template parameters, we could get a
2782 TYPE_DECL or a TEMPLATE_DECL. */
2783 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2784 parm = TREE_TYPE (parm);
2786 /* Otherwise it must be a type template parameter. */
2787 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2788 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2789 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2792 /* Determine if T is a function parameter pack. */
2795 function_parameter_pack_p (const_tree t)
2797 if (t && TREE_CODE (t) == PARM_DECL)
2798 return FUNCTION_PARAMETER_PACK_P (t);
2802 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2803 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2806 get_function_template_decl (const_tree primary_func_tmpl_inst)
2808 if (! primary_func_tmpl_inst
2809 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2810 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2813 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2816 /* Return true iff the function parameter PARAM_DECL was expanded
2817 from the function parameter pack PACK. */
2820 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2822 if (DECL_ARTIFICIAL (param_decl)
2823 || !function_parameter_pack_p (pack))
2826 /* The parameter pack and its pack arguments have the same
2828 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2831 /* Determine whether ARGS describes a variadic template args list,
2832 i.e., one that is terminated by a template argument pack. */
2835 template_args_variadic_p (tree args)
2840 if (args == NULL_TREE)
2843 args = INNERMOST_TEMPLATE_ARGS (args);
2844 nargs = TREE_VEC_LENGTH (args);
2849 last_parm = TREE_VEC_ELT (args, nargs - 1);
2851 return ARGUMENT_PACK_P (last_parm);
2854 /* Generate a new name for the parameter pack name NAME (an
2855 IDENTIFIER_NODE) that incorporates its */
2858 make_ith_pack_parameter_name (tree name, int i)
2860 /* Munge the name to include the parameter index. */
2861 #define NUMBUF_LEN 128
2862 char numbuf[NUMBUF_LEN];
2866 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2867 newname_len = IDENTIFIER_LENGTH (name)
2868 + strlen (numbuf) + 2;
2869 newname = (char*)alloca (newname_len);
2870 snprintf (newname, newname_len,
2871 "%s#%i", IDENTIFIER_POINTER (name), i);
2872 return get_identifier (newname);
2875 /* Return true if T is a primary function, class or alias template
2879 primary_template_instantiation_p (const_tree t)
2884 if (TREE_CODE (t) == FUNCTION_DECL)
2885 return DECL_LANG_SPECIFIC (t)
2886 && DECL_TEMPLATE_INSTANTIATION (t)
2887 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2888 else if (CLASS_TYPE_P (t) && !TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
2889 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2890 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2892 && TYPE_TEMPLATE_INFO (t)
2893 && PRIMARY_TEMPLATE_P (TYPE_TI_TEMPLATE (t))
2894 && DECL_TEMPLATE_INSTANTIATION (TYPE_NAME (t)))
2899 /* Return true if PARM is a template template parameter. */
2902 template_template_parameter_p (const_tree parm)
2904 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2907 /* Return the template parameters of T if T is a
2908 primary template instantiation, NULL otherwise. */
2911 get_primary_template_innermost_parameters (const_tree t)
2913 tree parms = NULL, template_info = NULL;
2915 if ((template_info = get_template_info (t))
2916 && primary_template_instantiation_p (t))
2917 parms = INNERMOST_TEMPLATE_PARMS
2918 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2923 /* Return the template parameters of the LEVELth level from the full list
2924 of template parameters PARMS. */
2927 get_template_parms_at_level (tree parms, int level)
2931 || TREE_CODE (parms) != TREE_LIST
2932 || level > TMPL_PARMS_DEPTH (parms))
2935 for (p = parms; p; p = TREE_CHAIN (p))
2936 if (TMPL_PARMS_DEPTH (p) == level)
2942 /* Returns the template arguments of T if T is a template instantiation,
2946 get_template_innermost_arguments (const_tree t)
2948 tree args = NULL, template_info = NULL;
2950 if ((template_info = get_template_info (t))
2951 && TI_ARGS (template_info))
2952 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2957 /* Return the argument pack elements of T if T is a template argument pack,
2961 get_template_argument_pack_elems (const_tree t)
2963 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2964 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2967 return ARGUMENT_PACK_ARGS (t);
2970 /* Structure used to track the progress of find_parameter_packs_r. */
2971 struct find_parameter_pack_data
2973 /* TREE_LIST that will contain all of the parameter packs found by
2975 tree* parameter_packs;
2977 /* Set of AST nodes that have been visited by the traversal. */
2978 struct pointer_set_t *visited;
2981 /* Identifies all of the argument packs that occur in a template
2982 argument and appends them to the TREE_LIST inside DATA, which is a
2983 find_parameter_pack_data structure. This is a subroutine of
2984 make_pack_expansion and uses_parameter_packs. */
2986 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2989 struct find_parameter_pack_data* ppd =
2990 (struct find_parameter_pack_data*)data;
2991 bool parameter_pack_p = false;
2993 /* Handle type aliases/typedefs. */
2996 && TREE_CODE (TYPE_NAME (t)) == TYPE_DECL
2997 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
2999 if (TYPE_TEMPLATE_INFO (t))
3000 cp_walk_tree (&TYPE_TI_ARGS (t),
3001 &find_parameter_packs_r,
3007 /* Identify whether this is a parameter pack or not. */
3008 switch (TREE_CODE (t))
3010 case TEMPLATE_PARM_INDEX:
3011 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3012 parameter_pack_p = true;
3015 case TEMPLATE_TYPE_PARM:
3016 t = TYPE_MAIN_VARIANT (t);
3017 case TEMPLATE_TEMPLATE_PARM:
3018 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3019 parameter_pack_p = true;
3023 if (FUNCTION_PARAMETER_PACK_P (t))
3025 /* We don't want to walk into the type of a PARM_DECL,
3026 because we don't want to see the type parameter pack. */
3028 parameter_pack_p = true;
3033 parameter_pack_p = true;
3036 /* Not a parameter pack. */
3040 if (parameter_pack_p)
3042 /* Add this parameter pack to the list. */
3043 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
3047 cp_walk_tree (&TYPE_CONTEXT (t),
3048 &find_parameter_packs_r, ppd, ppd->visited);
3050 /* This switch statement will return immediately if we don't find a
3052 switch (TREE_CODE (t))
3054 case TEMPLATE_PARM_INDEX:
3057 case BOUND_TEMPLATE_TEMPLATE_PARM:
3058 /* Check the template itself. */
3059 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
3060 &find_parameter_packs_r, ppd, ppd->visited);
3061 /* Check the template arguments. */
3062 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
3067 case TEMPLATE_TYPE_PARM:
3068 case TEMPLATE_TEMPLATE_PARM:
3075 if (TYPE_PTRMEMFUNC_P (t))
3081 if (TYPE_TEMPLATE_INFO (t))
3082 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3083 &find_parameter_packs_r, ppd, ppd->visited);
3090 cp_walk_tree (&TREE_TYPE (t),
3091 &find_parameter_packs_r, ppd, ppd->visited);
3095 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3100 case TYPE_PACK_EXPANSION:
3101 case EXPR_PACK_EXPANSION:
3106 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3111 case IDENTIFIER_NODE:
3112 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3124 /* Determines if the expression or type T uses any parameter packs. */
3126 uses_parameter_packs (tree t)
3128 tree parameter_packs = NULL_TREE;
3129 struct find_parameter_pack_data ppd;
3130 ppd.parameter_packs = ¶meter_packs;
3131 ppd.visited = pointer_set_create ();
3132 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3133 pointer_set_destroy (ppd.visited);
3134 return parameter_packs != NULL_TREE;
3137 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3138 representation a base-class initializer into a parameter pack
3139 expansion. If all goes well, the resulting node will be an
3140 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3143 make_pack_expansion (tree arg)
3146 tree parameter_packs = NULL_TREE;
3147 bool for_types = false;
3148 struct find_parameter_pack_data ppd;
3150 if (!arg || arg == error_mark_node)
3153 if (TREE_CODE (arg) == TREE_LIST)
3155 /* The only time we will see a TREE_LIST here is for a base
3156 class initializer. In this case, the TREE_PURPOSE will be a
3157 _TYPE node (representing the base class expansion we're
3158 initializing) and the TREE_VALUE will be a TREE_LIST
3159 containing the initialization arguments.
3161 The resulting expansion looks somewhat different from most
3162 expansions. Rather than returning just one _EXPANSION, we
3163 return a TREE_LIST whose TREE_PURPOSE is a
3164 TYPE_PACK_EXPANSION containing the bases that will be
3165 initialized. The TREE_VALUE will be identical to the
3166 original TREE_VALUE, which is a list of arguments that will
3167 be passed to each base. We do not introduce any new pack
3168 expansion nodes into the TREE_VALUE (although it is possible
3169 that some already exist), because the TREE_PURPOSE and
3170 TREE_VALUE all need to be expanded together with the same
3171 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3172 resulting TREE_PURPOSE will mention the parameter packs in
3173 both the bases and the arguments to the bases. */
3176 tree parameter_packs = NULL_TREE;
3178 /* Determine which parameter packs will be used by the base
3180 ppd.visited = pointer_set_create ();
3181 ppd.parameter_packs = ¶meter_packs;
3182 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3185 if (parameter_packs == NULL_TREE)
3187 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3188 pointer_set_destroy (ppd.visited);
3189 return error_mark_node;
3192 if (TREE_VALUE (arg) != void_type_node)
3194 /* Collect the sets of parameter packs used in each of the
3195 initialization arguments. */
3196 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3198 /* Determine which parameter packs will be expanded in this
3200 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3205 pointer_set_destroy (ppd.visited);
3207 /* Create the pack expansion type for the base type. */
3208 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3209 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3210 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3212 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3213 they will rarely be compared to anything. */
3214 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3216 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3219 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3222 /* Build the PACK_EXPANSION_* node. */
3224 ? cxx_make_type (TYPE_PACK_EXPANSION)
3225 : make_node (EXPR_PACK_EXPANSION);
3226 SET_PACK_EXPANSION_PATTERN (result, arg);
3227 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3229 /* Propagate type and const-expression information. */
3230 TREE_TYPE (result) = TREE_TYPE (arg);
3231 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3234 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3235 they will rarely be compared to anything. */
3236 SET_TYPE_STRUCTURAL_EQUALITY (result);
3238 /* Determine which parameter packs will be expanded. */
3239 ppd.parameter_packs = ¶meter_packs;
3240 ppd.visited = pointer_set_create ();
3241 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3242 pointer_set_destroy (ppd.visited);
3244 /* Make sure we found some parameter packs. */
3245 if (parameter_packs == NULL_TREE)
3248 error ("expansion pattern %<%T%> contains no argument packs", arg);
3250 error ("expansion pattern %<%E%> contains no argument packs", arg);
3251 return error_mark_node;
3253 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3255 PACK_EXPANSION_LOCAL_P (result) = at_function_scope_p ();
3260 /* Checks T for any "bare" parameter packs, which have not yet been
3261 expanded, and issues an error if any are found. This operation can
3262 only be done on full expressions or types (e.g., an expression
3263 statement, "if" condition, etc.), because we could have expressions like:
3265 foo(f(g(h(args)))...)
3267 where "args" is a parameter pack. check_for_bare_parameter_packs
3268 should not be called for the subexpressions args, h(args),
3269 g(h(args)), or f(g(h(args))), because we would produce erroneous
3272 Returns TRUE and emits an error if there were bare parameter packs,
3273 returns FALSE otherwise. */
3275 check_for_bare_parameter_packs (tree t)
3277 tree parameter_packs = NULL_TREE;
3278 struct find_parameter_pack_data ppd;
3280 if (!processing_template_decl || !t || t == error_mark_node)
3283 if (TREE_CODE (t) == TYPE_DECL)
3286 ppd.parameter_packs = ¶meter_packs;
3287 ppd.visited = pointer_set_create ();
3288 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3289 pointer_set_destroy (ppd.visited);
3291 if (parameter_packs)
3293 error ("parameter packs not expanded with %<...%>:");
3294 while (parameter_packs)
3296 tree pack = TREE_VALUE (parameter_packs);
3297 tree name = NULL_TREE;
3299 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3300 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3301 name = TYPE_NAME (pack);
3302 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3303 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3305 name = DECL_NAME (pack);
3308 inform (input_location, " %qD", name);
3310 inform (input_location, " <anonymous>");
3312 parameter_packs = TREE_CHAIN (parameter_packs);
3321 /* Expand any parameter packs that occur in the template arguments in
3324 expand_template_argument_pack (tree args)
3326 tree result_args = NULL_TREE;
3327 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3328 int num_result_args = -1;
3329 int non_default_args_count = -1;
3331 /* First, determine if we need to expand anything, and the number of
3332 slots we'll need. */
3333 for (in_arg = 0; in_arg < nargs; ++in_arg)
3335 tree arg = TREE_VEC_ELT (args, in_arg);
3336 if (arg == NULL_TREE)
3338 if (ARGUMENT_PACK_P (arg))
3340 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3341 if (num_result_args < 0)
3342 num_result_args = in_arg + num_packed;
3344 num_result_args += num_packed;
3348 if (num_result_args >= 0)
3353 /* If no expansion is necessary, we're done. */
3354 if (num_result_args < 0)
3357 /* Expand arguments. */
3358 result_args = make_tree_vec (num_result_args);
3359 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3360 non_default_args_count =
3361 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3362 for (in_arg = 0; in_arg < nargs; ++in_arg)
3364 tree arg = TREE_VEC_ELT (args, in_arg);
3365 if (ARGUMENT_PACK_P (arg))
3367 tree packed = ARGUMENT_PACK_ARGS (arg);
3368 int i, num_packed = TREE_VEC_LENGTH (packed);
3369 for (i = 0; i < num_packed; ++i, ++out_arg)
3370 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3371 if (non_default_args_count > 0)
3372 non_default_args_count += num_packed;
3376 TREE_VEC_ELT (result_args, out_arg) = arg;
3380 if (non_default_args_count >= 0)
3381 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3385 /* Checks if DECL shadows a template parameter.
3387 [temp.local]: A template-parameter shall not be redeclared within its
3388 scope (including nested scopes).
3390 Emits an error and returns TRUE if the DECL shadows a parameter,
3391 returns FALSE otherwise. */
3394 check_template_shadow (tree decl)
3398 /* If we're not in a template, we can't possibly shadow a template
3400 if (!current_template_parms)
3403 /* Figure out what we're shadowing. */
3404 if (TREE_CODE (decl) == OVERLOAD)
3405 decl = OVL_CURRENT (decl);
3406 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3408 /* If there's no previous binding for this name, we're not shadowing
3409 anything, let alone a template parameter. */
3413 /* If we're not shadowing a template parameter, we're done. Note
3414 that OLDDECL might be an OVERLOAD (or perhaps even an
3415 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3417 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3420 /* We check for decl != olddecl to avoid bogus errors for using a
3421 name inside a class. We check TPFI to avoid duplicate errors for
3422 inline member templates. */
3424 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3427 error ("declaration of %q+#D", decl);
3428 error (" shadows template parm %q+#D", olddecl);
3432 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3433 ORIG_LEVEL, DECL, and TYPE. NUM_SIBLINGS is the total number of
3434 template parameters. */
3437 build_template_parm_index (int index,
3444 tree t = make_node (TEMPLATE_PARM_INDEX);
3445 TEMPLATE_PARM_IDX (t) = index;
3446 TEMPLATE_PARM_LEVEL (t) = level;
3447 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3448 TEMPLATE_PARM_NUM_SIBLINGS (t) = num_siblings;
3449 TEMPLATE_PARM_DECL (t) = decl;
3450 TREE_TYPE (t) = type;
3451 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3452 TREE_READONLY (t) = TREE_READONLY (decl);
3457 /* Find the canonical type parameter for the given template type
3458 parameter. Returns the canonical type parameter, which may be TYPE
3459 if no such parameter existed. */
3462 canonical_type_parameter (tree type)
3465 int idx = TEMPLATE_TYPE_IDX (type);
3466 if (!canonical_template_parms)
3467 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3469 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3470 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3472 list = VEC_index (tree, canonical_template_parms, idx);
3473 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3474 list = TREE_CHAIN (list);
3477 return TREE_VALUE (list);
3480 VEC_replace(tree, canonical_template_parms, idx,
3481 tree_cons (NULL_TREE, type,
3482 VEC_index (tree, canonical_template_parms, idx)));
3487 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3488 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3489 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3490 new one is created. */
3493 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3494 tsubst_flags_t complain)
3496 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3497 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3498 != TEMPLATE_PARM_LEVEL (index) - levels)
3499 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3501 tree orig_decl = TEMPLATE_PARM_DECL (index);
3504 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3505 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3506 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3507 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3508 DECL_ARTIFICIAL (decl) = 1;
3509 SET_DECL_TEMPLATE_PARM_P (decl);
3511 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3512 TEMPLATE_PARM_LEVEL (index) - levels,
3513 TEMPLATE_PARM_ORIG_LEVEL (index),
3514 TEMPLATE_PARM_NUM_SIBLINGS (index),
3516 TEMPLATE_PARM_DESCENDANTS (index) = t;
3517 TEMPLATE_PARM_PARAMETER_PACK (t)
3518 = TEMPLATE_PARM_PARAMETER_PACK (index);
3520 /* Template template parameters need this. */
3521 if (TREE_CODE (decl) == TEMPLATE_DECL)
3522 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3523 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3527 return TEMPLATE_PARM_DESCENDANTS (index);
3530 /* Process information from new template parameter PARM and append it
3531 to the LIST being built. This new parameter is a non-type
3532 parameter iff IS_NON_TYPE is true. This new parameter is a
3533 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3534 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3535 parameter list PARM belongs to. This is used used to create a
3536 proper canonical type for the type of PARM that is to be created,
3537 iff PARM is a type. If the size is not known, this parameter shall
3541 process_template_parm (tree list, location_t parm_loc, tree parm,
3542 bool is_non_type, bool is_parameter_pack,
3543 unsigned num_template_parms)
3550 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3551 defval = TREE_PURPOSE (parm);
3555 tree p = tree_last (list);
3557 if (p && TREE_VALUE (p) != error_mark_node)
3560 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3561 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3563 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3573 parm = TREE_VALUE (parm);
3575 SET_DECL_TEMPLATE_PARM_P (parm);
3577 if (TREE_TYPE (parm) == error_mark_node)
3579 err_parm_list = build_tree_list (defval, parm);
3580 TREE_VALUE (err_parm_list) = error_mark_node;
3581 return chainon (list, err_parm_list);
3587 The top-level cv-qualifiers on the template-parameter are
3588 ignored when determining its type. */
3589 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3590 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3592 err_parm_list = build_tree_list (defval, parm);
3593 TREE_VALUE (err_parm_list) = error_mark_node;
3594 return chainon (list, err_parm_list);
3597 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3599 /* This template parameter is not a parameter pack, but it
3600 should be. Complain about "bare" parameter packs. */
3601 check_for_bare_parameter_packs (TREE_TYPE (parm));
3603 /* Recover by calling this a parameter pack. */
3604 is_parameter_pack = true;
3608 /* A template parameter is not modifiable. */
3609 TREE_CONSTANT (parm) = 1;
3610 TREE_READONLY (parm) = 1;
3611 decl = build_decl (parm_loc,
3612 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3613 TREE_CONSTANT (decl) = 1;
3614 TREE_READONLY (decl) = 1;
3615 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3616 = build_template_parm_index (idx, processing_template_decl,
3617 processing_template_decl,
3619 decl, TREE_TYPE (parm));
3621 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3622 = is_parameter_pack;
3627 parm = TREE_VALUE (TREE_VALUE (parm));
3629 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3631 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3632 /* This is for distinguishing between real templates and template
3633 template parameters */
3634 TREE_TYPE (parm) = t;
3635 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3640 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3641 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3642 decl = build_decl (parm_loc,
3643 TYPE_DECL, parm, t);
3646 TYPE_NAME (t) = decl;
3647 TYPE_STUB_DECL (t) = decl;
3649 TEMPLATE_TYPE_PARM_INDEX (t)
3650 = build_template_parm_index (idx, processing_template_decl,
3651 processing_template_decl,
3653 decl, TREE_TYPE (parm));
3654 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3655 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3657 DECL_ARTIFICIAL (decl) = 1;
3658 SET_DECL_TEMPLATE_PARM_P (decl);
3660 parm = build_tree_list (defval, parm);
3661 return chainon (list, parm);
3664 /* The end of a template parameter list has been reached. Process the
3665 tree list into a parameter vector, converting each parameter into a more
3666 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3670 end_template_parm_list (tree parms)
3674 tree saved_parmlist = make_tree_vec (list_length (parms));
3676 current_template_parms
3677 = tree_cons (size_int (processing_template_decl),
3678 saved_parmlist, current_template_parms);
3680 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3682 next = TREE_CHAIN (parm);
3683 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3684 TREE_CHAIN (parm) = NULL_TREE;
3687 --processing_template_parmlist;
3689 return saved_parmlist;
3692 /* Create a new type almost identical to TYPE but which has the
3693 following differences:
3695 1/ T has a new TEMPLATE_PARM_INDEX that carries the new number of
3696 template sibling parameters of T.
3698 2/ T has a new canonical type that matches the new number
3701 3/ From now on, T is going to be what lookups referring to the
3702 name of TYPE will return. No lookup should return TYPE anymore.
3704 NUM_PARMS is the new number of sibling parms TYPE belongs to.
3706 This is a subroutine of fixup_template_parms. */
3709 fixup_template_type_parm_type (tree type, int num_parms)
3711 tree orig_idx = TEMPLATE_TYPE_PARM_INDEX (type), idx;
3713 /* This is the decl which name is inserted into the symbol table for
3714 the template parm type. So whenever we lookup the type name, this
3715 is the DECL we get. */
3718 /* Do not fix up the type twice. */
3719 if (orig_idx && TEMPLATE_PARM_NUM_SIBLINGS (orig_idx) != 0)
3722 t = copy_type (type);
3723 decl = TYPE_NAME (t);
3725 TYPE_MAIN_VARIANT (t) = t;
3726 TYPE_NEXT_VARIANT (t)= NULL_TREE;
3727 TYPE_POINTER_TO (t) = 0;
3728 TYPE_REFERENCE_TO (t) = 0;
3730 idx = build_template_parm_index (TEMPLATE_PARM_IDX (orig_idx),
3731 TEMPLATE_PARM_LEVEL (orig_idx),
3732 TEMPLATE_PARM_ORIG_LEVEL (orig_idx),
3735 TEMPLATE_PARM_DESCENDANTS (idx) = TEMPLATE_PARM_DESCENDANTS (orig_idx);
3736 TEMPLATE_PARM_PARAMETER_PACK (idx) = TEMPLATE_PARM_PARAMETER_PACK (orig_idx);
3737 TEMPLATE_TYPE_PARM_INDEX (t) = idx;
3739 TYPE_STUB_DECL (t) = decl;
3740 TEMPLATE_TYPE_DECL (t) = decl;
3741 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
3742 TREE_TYPE (DECL_TEMPLATE_RESULT (decl)) = t;
3744 /* Update the type associated to the type name stored in the symbol
3745 table. Now, whenever the type name is looked up, the resulting
3746 type is properly fixed up. */
3747 TREE_TYPE (decl) = t;
3749 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3754 /* Create and return a new TEMPLATE_PARM_INDEX that is almost
3755 identical to I, but that is fixed up as to:
3757 1/ carry the number of sibling parms (NUM_PARMS) of the template
3758 parm represented by I.
3760 2/ replace all references to template parm types declared before I
3761 (in the same template parm list as I) by references to template
3762 parm types contained in ARGS. ARGS should contain the list of
3763 template parms that have been fixed up so far, in a form suitable
3764 to be passed to tsubst.
3766 This is a subroutine of fixup_template_parms. */
3769 fixup_template_parm_index (tree i, tree args, int num_parms)
3771 tree index, decl, type;
3774 || TREE_CODE (i) != TEMPLATE_PARM_INDEX
3775 /* Do not fix up the index twice. */
3776 || (TEMPLATE_PARM_NUM_SIBLINGS (i) != 0))
3779 decl = TEMPLATE_PARM_DECL (i);
3780 type = TREE_TYPE (decl);
3782 index = build_template_parm_index (TEMPLATE_PARM_IDX (i),
3783 TEMPLATE_PARM_LEVEL (i),
3784 TEMPLATE_PARM_ORIG_LEVEL (i),
3788 TEMPLATE_PARM_DESCENDANTS (index) = TEMPLATE_PARM_DESCENDANTS (i);
3789 TEMPLATE_PARM_PARAMETER_PACK (index) = TEMPLATE_PARM_PARAMETER_PACK (i);
3791 type = tsubst (type, args, tf_none, NULL_TREE);
3793 TREE_TYPE (decl) = type;
3794 TREE_TYPE (index) = type;
3800 This is a subroutine of fixup_template_parms.
3802 It computes the canonical type of the type of the template
3803 parameter PARM_DESC and update all references to that type so that
3804 they use the newly computed canonical type. No access check is
3805 performed during the fixup. PARM_DESC is a TREE_LIST which
3806 TREE_VALUE is the template parameter and its TREE_PURPOSE is the
3807 default argument of the template parm if any. IDX is the index of
3808 the template parameter, starting at 0. NUM_PARMS is the number of
3809 template parameters in the set PARM_DESC belongs to. ARGLIST is a
3810 TREE_VEC containing the full set of template parameters in a form
3811 suitable to be passed to substs functions as their ARGS
3812 argument. This is what current_template_args returns for a given
3813 template. The innermost vector of args in ARGLIST is the set of
3814 template parms that have been fixed up so far. This function adds
3815 the fixed up parameter into that vector. */
3818 fixup_template_parm (tree parm_desc,
3823 tree parm = TREE_VALUE (parm_desc);
3824 tree fixedup_args = INNERMOST_TEMPLATE_ARGS (arglist);
3826 push_deferring_access_checks (dk_no_check);
3828 if (TREE_CODE (parm) == TYPE_DECL)
3830 /* PARM is a template type parameter. Fix up its type, add
3831 the fixed-up template parm to the vector of fixed-up
3832 template parms so far, and substitute the fixed-up
3833 template parms into the default argument of this
3836 fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3837 TREE_TYPE (parm) = t;
3839 TREE_VEC_ELT (fixedup_args, idx) = template_parm_to_arg (parm_desc);
3841 else if (TREE_CODE (parm) == TEMPLATE_DECL)
3843 /* PARM is a template template parameter. This is going to
3845 tree tparms, targs, innermost_args, t;
3848 /* First, fix up the parms of the template template parm
3849 because the parms are involved in defining the new canonical
3850 type of the template template parm. */
3852 /* So we need to substitute the template parm types that have
3853 been fixed up so far into the template parms of this template
3854 template parm. E.g, consider this:
3856 template<class T, template<T u> class TT> class S;
3858 In this case we want to substitute T into the
3859 template parameters of TT.
3861 So let's walk the template parms of PARM here, and
3862 tsubst ARGLIST into into each of the template
3865 /* For this substitution we need to build the full set of
3866 template parameters and use that as arguments for the
3867 tsubsting function. */
3868 tparms = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (parm));
3870 /* This will contain the innermost parms of PARM into which
3871 we have substituted so far. */
3872 innermost_args = make_tree_vec (TREE_VEC_LENGTH (tparms));
3873 targs = add_to_template_args (arglist, innermost_args);
3874 for (j = 0; j < TREE_VEC_LENGTH (tparms); ++j)
3878 parameter = TREE_VEC_ELT (tparms, j);
3880 /* INNERMOST_ARGS needs to have at least the same number
3881 of elements as the index PARAMETER, ortherwise
3882 tsubsting into PARAMETER will result in partially
3883 instantiating it, reducing its tempate parm
3884 level. Let's tactically fill INNERMOST_ARGS for that
3886 TREE_VEC_ELT (innermost_args, j) =
3887 template_parm_to_arg (parameter);
3889 fixup_template_parm (parameter, j,
3890 TREE_VEC_LENGTH (tparms),
3894 /* Now fix up the type of the template template parm. */
3896 t = fixup_template_type_parm_type (TREE_TYPE (parm), num_parms);
3897 TREE_TYPE (parm) = t;
3899 TREE_VEC_ELT (fixedup_args, idx) =
3900 template_parm_to_arg (parm_desc);
3902 else if (TREE_CODE (parm) == PARM_DECL)
3904 /* PARM is a non-type template parameter. We need to:
3906 * Fix up its TEMPLATE_PARM_INDEX to make it carry the
3907 proper number of sibling parameters.
3909 * Make lookups of the template parameter return a reference
3910 to the fixed-up index. No lookup should return references
3911 to the former index anymore.
3913 * Substitute the template parms that got fixed up so far
3915 * into the type of PARM. */
3917 tree index = DECL_INITIAL (parm);
3919 /* PUSHED_DECL is the decl added to the symbol table with
3920 the name of the parameter. E,g:
3922 template<class T, T u> //#0
3923 auto my_function(T t) -> decltype(u); //#1
3925 Here, when looking up u at //#1, we get the decl of u
3926 resulting from the declaration in #0. This is what
3927 PUSHED_DECL is. We need to replace the reference to the
3928 old TEMPLATE_PARM_INDEX carried by PUSHED_DECL by the
3929 fixed-up TEMPLATE_PARM_INDEX. */
3930 tree pushed_decl = TEMPLATE_PARM_DECL (index);
3932 /* Let's fix up the TEMPLATE_PARM_INDEX then. Note that we must
3933 fixup the type of PUSHED_DECL as well and luckily
3934 fixup_template_parm_index does it for us too. */
3935 tree fixed_up_index =
3936 fixup_template_parm_index (index, arglist, num_parms);
3938 DECL_INITIAL (pushed_decl) = DECL_INITIAL (parm) = fixed_up_index;
3940 /* Add this fixed up PARM to the template parms we've fixed
3941 up so far and use that to substitute the fixed-up
3942 template parms into the type of PARM. */
3943 TREE_VEC_ELT (fixedup_args, idx) =
3944 template_parm_to_arg (parm_desc);
3945 TREE_TYPE (parm) = tsubst (TREE_TYPE (parm), arglist,
3946 tf_none, NULL_TREE);
3949 TREE_PURPOSE (parm_desc) =
3950 tsubst_template_arg (TREE_PURPOSE (parm_desc),
3951 arglist, tf_none, parm);
3953 pop_deferring_access_checks ();
3956 /* Walk the current template parms and properly compute the canonical
3957 types of the dependent types created during
3958 cp_parser_template_parameter_list. */
3961 fixup_template_parms (void)
3968 parameter_vec = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3969 if (parameter_vec == NULL_TREE)
3972 num_parms = TREE_VEC_LENGTH (parameter_vec);
3974 /* This vector contains the current innermost template parms that
3975 have been fixed up so far. The form of FIXEDUP_ARGS is suitable
3976 to be passed to tsubst* functions as their ARGS argument. */
3977 fixedup_args = make_tree_vec (num_parms);
3979 /* This vector contains the full set of template parms in a form
3980 suitable to be passed to substs functions as their ARGS
3982 arglist = current_template_args ();
3983 arglist = add_outermost_template_args (arglist, fixedup_args);
3985 /* Let's do the proper fixup now. */
3986 for (i = 0; i < num_parms; ++i)
3987 fixup_template_parm (TREE_VEC_ELT (parameter_vec, i),
3988 i, num_parms, arglist);
3991 /* end_template_decl is called after a template declaration is seen. */
3994 end_template_decl (void)
3996 reset_specialization ();
3998 if (! processing_template_decl)
4001 /* This matches the pushlevel in begin_template_parm_list. */
4004 --processing_template_decl;
4005 current_template_parms = TREE_CHAIN (current_template_parms);
4008 /* Takes a TREE_LIST representing a template parameter and convert it
4009 into an argument suitable to be passed to the type substitution
4010 functions. Note that If the TREE_LIST contains an error_mark
4011 node, the returned argument is error_mark_node. */
4014 template_parm_to_arg (tree t)
4018 || TREE_CODE (t) != TREE_LIST)
4021 if (error_operand_p (TREE_VALUE (t)))
4022 return error_mark_node;
4026 if (TREE_CODE (t) == TYPE_DECL
4027 || TREE_CODE (t) == TEMPLATE_DECL)
4031 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
4033 /* Turn this argument into a TYPE_ARGUMENT_PACK
4034 with a single element, which expands T. */
4035 tree vec = make_tree_vec (1);
4036 #ifdef ENABLE_CHECKING
4037 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4038 (vec, TREE_VEC_LENGTH (vec));
4040 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4042 t = cxx_make_type (TYPE_ARGUMENT_PACK);
4043 SET_ARGUMENT_PACK_ARGS (t, vec);
4048 t = DECL_INITIAL (t);
4050 if (TEMPLATE_PARM_PARAMETER_PACK (t))
4052 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
4053 with a single element, which expands T. */
4054 tree vec = make_tree_vec (1);
4055 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
4056 #ifdef ENABLE_CHECKING
4057 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
4058 (vec, TREE_VEC_LENGTH (vec));
4060 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
4062 t = make_node (NONTYPE_ARGUMENT_PACK);
4063 SET_ARGUMENT_PACK_ARGS (t, vec);
4064 TREE_TYPE (t) = type;
4070 /* This function returns TRUE if PARM_PACK is a template parameter
4071 pack and if ARG_PACK is what template_parm_to_arg returned when
4072 passed PARM_PACK. */
4075 arg_from_parm_pack_p (tree arg_pack, tree parm_pack)
4077 /* For clarity in the comments below let's use the representation
4078 argument_pack<elements>' to denote an argument pack and its
4081 In the 'if' block below, we want to detect cases where
4082 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to
4083 check if ARG_PACK is an argument pack which sole element is
4084 the expansion of PARM_PACK. That argument pack is typically
4085 created by template_parm_to_arg when passed a parameter
4089 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
4090 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
4092 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
4093 tree pattern = PACK_EXPANSION_PATTERN (expansion);
4094 /* So we have an argument_pack<P...>. We want to test if P
4095 is actually PARM_PACK. We will not use cp_tree_equal to
4096 test P and PARM_PACK because during type fixup (by
4097 fixup_template_parm) P can be a pre-fixup version of a
4098 type and PARM_PACK be its post-fixup version.
4099 cp_tree_equal would consider them as different even
4100 though we would want to consider them compatible for our
4101 precise purpose here.
4103 Thus we are going to consider that P and PARM_PACK are
4104 compatible if they have the same DECL. */
4105 if ((/* If ARG_PACK is a type parameter pack named by the
4106 same DECL as parm_pack ... */
4108 && TYPE_P (parm_pack)
4109 && TYPE_NAME (pattern) == TYPE_NAME (parm_pack))
4110 /* ... or if PARM_PACK is a non-type parameter named by the
4111 same DECL as ARG_PACK. Note that PARM_PACK being a
4112 non-type parameter means it's either a PARM_DECL or a
4113 TEMPLATE_PARM_INDEX. */
4114 || (TREE_CODE (pattern) == TEMPLATE_PARM_INDEX
4115 && ((TREE_CODE (parm_pack) == PARM_DECL
4116 && (TEMPLATE_PARM_DECL (pattern)
4117 == TEMPLATE_PARM_DECL (DECL_INITIAL (parm_pack))))
4118 || (TREE_CODE (parm_pack) == TEMPLATE_PARM_INDEX
4119 && (TEMPLATE_PARM_DECL (pattern)
4120 == TEMPLATE_PARM_DECL (parm_pack))))))
4121 && template_parameter_pack_p (pattern))
4127 /* Within the declaration of a template, return all levels of template
4128 parameters that apply. The template parameters are represented as
4129 a TREE_VEC, in the form documented in cp-tree.h for template
4133 current_template_args (void)
4136 tree args = NULL_TREE;
4137 int length = TMPL_PARMS_DEPTH (current_template_parms);
4140 /* If there is only one level of template parameters, we do not
4141 create a TREE_VEC of TREE_VECs. Instead, we return a single
4142 TREE_VEC containing the arguments. */
4144 args = make_tree_vec (length);
4146 for (header = current_template_parms; header; header = TREE_CHAIN (header))
4148 tree a = copy_node (TREE_VALUE (header));
4151 TREE_TYPE (a) = NULL_TREE;
4152 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
4153 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
4155 #ifdef ENABLE_CHECKING
4156 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
4160 TREE_VEC_ELT (args, --l) = a;
4165 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
4166 /* This can happen for template parms of a template template
4169 template<template<class T, class U> class TT> struct S;
4171 Consider the level of the parms of TT; T and U both have
4172 level 2; TT has no template parm of level 1. So in this case
4173 the first element of full_template_args is NULL_TREE. If we
4174 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
4175 of 2. This will make tsubst wrongly consider that T and U
4176 have level 1. Instead, let's create a dummy vector as the
4177 first element of full_template_args so that TMPL_ARG_DEPTH
4178 returns the correct depth for args. */
4179 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
4183 /* Update the declared TYPE by doing any lookups which were thought to be
4184 dependent, but are not now that we know the SCOPE of the declarator. */
4187 maybe_update_decl_type (tree orig_type, tree scope)
4189 tree type = orig_type;
4191 if (type == NULL_TREE)
4194 if (TREE_CODE (orig_type) == TYPE_DECL)
4195 type = TREE_TYPE (type);
4197 if (scope && TYPE_P (scope) && dependent_type_p (scope)
4198 && dependent_type_p (type)
4199 /* Don't bother building up the args in this case. */
4200 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
4202 /* tsubst in the args corresponding to the template parameters,
4203 including auto if present. Most things will be unchanged, but
4204 make_typename_type and tsubst_qualified_id will resolve
4205 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
4206 tree args = current_template_args ();
4207 tree auto_node = type_uses_auto (type);
4211 tree auto_vec = make_tree_vec (1);
4212 TREE_VEC_ELT (auto_vec, 0) = auto_node;
4213 args = add_to_template_args (args, auto_vec);
4215 pushed = push_scope (scope);
4216 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
4221 if (type == error_mark_node)
4224 if (TREE_CODE (orig_type) == TYPE_DECL)
4226 if (same_type_p (type, TREE_TYPE (orig_type)))
4229 type = TYPE_NAME (type);
4234 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
4235 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
4236 a member template. Used by push_template_decl below. */
4239 build_template_decl (tree decl, tree parms, bool member_template_p)
4241 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
4242 DECL_TEMPLATE_PARMS (tmpl) = parms;
4243 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
4244 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
4245 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
4250 struct template_parm_data
4252 /* The level of the template parameters we are currently
4256 /* The index of the specialization argument we are currently
4260 /* An array whose size is the number of template parameters. The
4261 elements are nonzero if the parameter has been used in any one
4262 of the arguments processed so far. */
4265 /* An array whose size is the number of template arguments. The
4266 elements are nonzero if the argument makes use of template
4267 parameters of this level. */
4268 int* arg_uses_template_parms;
4271 /* Subroutine of push_template_decl used to see if each template
4272 parameter in a partial specialization is used in the explicit
4273 argument list. If T is of the LEVEL given in DATA (which is
4274 treated as a template_parm_data*), then DATA->PARMS is marked
4278 mark_template_parm (tree t, void* data)
4282 struct template_parm_data* tpd = (struct template_parm_data*) data;
4284 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4286 level = TEMPLATE_PARM_LEVEL (t);
4287 idx = TEMPLATE_PARM_IDX (t);
4291 level = TEMPLATE_TYPE_LEVEL (t);
4292 idx = TEMPLATE_TYPE_IDX (t);
4295 if (level == tpd->level)
4297 tpd->parms[idx] = 1;
4298 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4301 /* Return zero so that for_each_template_parm will continue the
4302 traversal of the tree; we want to mark *every* template parm. */
4306 /* Process the partial specialization DECL. */
4309 process_partial_specialization (tree decl)
4311 tree type = TREE_TYPE (decl);
4312 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4313 tree specargs = CLASSTYPE_TI_ARGS (type);
4314 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4315 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4318 int nargs = TREE_VEC_LENGTH (inner_args);
4321 bool did_error_intro = false;
4322 struct template_parm_data tpd;
4323 struct template_parm_data tpd2;
4325 gcc_assert (current_template_parms);
4327 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4328 ntparms = TREE_VEC_LENGTH (inner_parms);
4330 /* We check that each of the template parameters given in the
4331 partial specialization is used in the argument list to the
4332 specialization. For example:
4334 template <class T> struct S;
4335 template <class T> struct S<T*>;
4337 The second declaration is OK because `T*' uses the template
4338 parameter T, whereas
4340 template <class T> struct S<int>;
4342 is no good. Even trickier is:
4353 The S2<T> declaration is actually invalid; it is a
4354 full-specialization. Of course,
4357 struct S2<T (*)(U)>;
4359 or some such would have been OK. */
4360 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4361 tpd.parms = XALLOCAVEC (int, ntparms);
4362 memset (tpd.parms, 0, sizeof (int) * ntparms);
4364 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4365 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4366 for (i = 0; i < nargs; ++i)
4368 tpd.current_arg = i;
4369 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4370 &mark_template_parm,
4373 /*include_nondeduced_p=*/false);
4375 for (i = 0; i < ntparms; ++i)
4376 if (tpd.parms[i] == 0)
4378 /* One of the template parms was not used in the
4380 if (!did_error_intro)
4382 error ("template parameters not used in partial specialization:");
4383 did_error_intro = true;
4386 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4389 if (did_error_intro)
4390 return error_mark_node;
4392 /* [temp.class.spec]
4394 The argument list of the specialization shall not be identical to
4395 the implicit argument list of the primary template. */
4396 if (comp_template_args
4398 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4400 error ("partial specialization %qT does not specialize any template arguments", type);
4402 /* [temp.class.spec]
4404 A partially specialized non-type argument expression shall not
4405 involve template parameters of the partial specialization except
4406 when the argument expression is a simple identifier.
4408 The type of a template parameter corresponding to a specialized
4409 non-type argument shall not be dependent on a parameter of the
4412 Also, we verify that pack expansions only occur at the
4413 end of the argument list. */
4414 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4416 for (i = 0; i < nargs; ++i)
4418 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4419 tree arg = TREE_VEC_ELT (inner_args, i);
4420 tree packed_args = NULL_TREE;
4423 if (ARGUMENT_PACK_P (arg))
4425 /* Extract the arguments from the argument pack. We'll be
4426 iterating over these in the following loop. */
4427 packed_args = ARGUMENT_PACK_ARGS (arg);
4428 len = TREE_VEC_LENGTH (packed_args);
4431 for (j = 0; j < len; j++)
4434 /* Get the Jth argument in the parameter pack. */
4435 arg = TREE_VEC_ELT (packed_args, j);
4437 if (PACK_EXPANSION_P (arg))
4439 /* Pack expansions must come at the end of the
4441 if ((packed_args && j < len - 1)
4442 || (!packed_args && i < nargs - 1))
4444 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4445 error ("parameter pack argument %qE must be at the "
4446 "end of the template argument list", arg);
4448 error ("parameter pack argument %qT must be at the "
4449 "end of the template argument list", arg);
4453 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4454 /* We only care about the pattern. */
4455 arg = PACK_EXPANSION_PATTERN (arg);
4457 if (/* These first two lines are the `non-type' bit. */
4459 && TREE_CODE (arg) != TEMPLATE_DECL
4460 /* This next line is the `argument expression is not just a
4461 simple identifier' condition and also the `specialized
4462 non-type argument' bit. */
4463 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4465 if ((!packed_args && tpd.arg_uses_template_parms[i])
4466 || (packed_args && uses_template_parms (arg)))
4467 error ("template argument %qE involves template parameter(s)",
4471 /* Look at the corresponding template parameter,
4472 marking which template parameters its type depends
4474 tree type = TREE_TYPE (parm);
4478 /* We haven't yet initialized TPD2. Do so now. */
4479 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4480 /* The number of parameters here is the number in the
4481 main template, which, as checked in the assertion
4483 tpd2.parms = XALLOCAVEC (int, nargs);
4485 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4488 /* Mark the template parameters. But this time, we're
4489 looking for the template parameters of the main
4490 template, not in the specialization. */
4491 tpd2.current_arg = i;
4492 tpd2.arg_uses_template_parms[i] = 0;
4493 memset (tpd2.parms, 0, sizeof (int) * nargs);
4494 for_each_template_parm (type,
4495 &mark_template_parm,
4498 /*include_nondeduced_p=*/false);
4500 if (tpd2.arg_uses_template_parms [i])
4502 /* The type depended on some template parameters.
4503 If they are fully specialized in the
4504 specialization, that's OK. */
4507 for (j = 0; j < nargs; ++j)
4508 if (tpd2.parms[j] != 0
4509 && tpd.arg_uses_template_parms [j])
4512 error_n (input_location, count,
4513 "type %qT of template argument %qE depends "
4514 "on a template parameter",
4515 "type %qT of template argument %qE depends "
4516 "on template parameters",
4525 /* We should only get here once. */
4526 gcc_assert (!COMPLETE_TYPE_P (type));
4528 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4529 = tree_cons (specargs, inner_parms,
4530 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4531 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4533 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4534 inst = TREE_CHAIN (inst))
4536 tree inst_type = TREE_VALUE (inst);
4537 if (COMPLETE_TYPE_P (inst_type)
4538 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4540 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4541 if (spec && TREE_TYPE (spec) == type)
4542 permerror (input_location,
4543 "partial specialization of %qT after instantiation "
4544 "of %qT", type, inst_type);
4551 /* Check that a template declaration's use of default arguments and
4552 parameter packs is not invalid. Here, PARMS are the template
4553 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
4554 a primary template. IS_PARTIAL is nonzero if DECL is a partial
4558 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4559 declaration (but not a definition); 1 indicates a declaration, 2
4560 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4561 emitted for extraneous default arguments.
4563 Returns TRUE if there were no errors found, FALSE otherwise. */
4566 check_default_tmpl_args (tree decl, tree parms, int is_primary,
4567 int is_partial, int is_friend_decl)
4570 int last_level_to_check;
4572 bool no_errors = true;
4576 A default template-argument shall not be specified in a
4577 function template declaration or a function template definition, nor
4578 in the template-parameter-list of the definition of a member of a
4581 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4582 /* You can't have a function template declaration in a local
4583 scope, nor you can you define a member of a class template in a
4587 if (current_class_type
4588 && !TYPE_BEING_DEFINED (current_class_type)
4589 && DECL_LANG_SPECIFIC (decl)
4590 && DECL_DECLARES_FUNCTION_P (decl)
4591 /* If this is either a friend defined in the scope of the class
4592 or a member function. */
4593 && (DECL_FUNCTION_MEMBER_P (decl)
4594 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4595 : DECL_FRIEND_CONTEXT (decl)
4596 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4598 /* And, if it was a member function, it really was defined in
4599 the scope of the class. */
4600 && (!DECL_FUNCTION_MEMBER_P (decl)
4601 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4602 /* We already checked these parameters when the template was
4603 declared, so there's no need to do it again now. This function
4604 was defined in class scope, but we're processing it's body now
4605 that the class is complete. */
4608 /* Core issue 226 (C++0x only): the following only applies to class
4610 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
4614 If a template-parameter has a default template-argument, all
4615 subsequent template-parameters shall have a default
4616 template-argument supplied. */
4617 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4619 tree inner_parms = TREE_VALUE (parm_level);
4620 int ntparms = TREE_VEC_LENGTH (inner_parms);
4621 int seen_def_arg_p = 0;
4624 for (i = 0; i < ntparms; ++i)
4626 tree parm = TREE_VEC_ELT (inner_parms, i);
4628 if (parm == error_mark_node)
4631 if (TREE_PURPOSE (parm))
4633 else if (seen_def_arg_p
4634 && !template_parameter_pack_p (TREE_VALUE (parm)))
4636 error ("no default argument for %qD", TREE_VALUE (parm));
4637 /* For better subsequent error-recovery, we indicate that
4638 there should have been a default argument. */
4639 TREE_PURPOSE (parm) = error_mark_node;
4645 /* Don't complain about an enclosing partial
4647 && parm_level == parms
4648 && TREE_CODE (decl) == TYPE_DECL
4650 && template_parameter_pack_p (TREE_VALUE (parm)))
4652 /* A primary class template can only have one
4653 parameter pack, at the end of the template
4656 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4657 error ("parameter pack %qE must be at the end of the"
4658 " template parameter list", TREE_VALUE (parm));
4660 error ("parameter pack %qT must be at the end of the"
4661 " template parameter list",
4662 TREE_TYPE (TREE_VALUE (parm)));
4664 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4672 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4676 /* For an ordinary class template, default template arguments are
4677 allowed at the innermost level, e.g.:
4678 template <class T = int>
4680 but, in a partial specialization, they're not allowed even
4681 there, as we have in [temp.class.spec]:
4683 The template parameter list of a specialization shall not
4684 contain default template argument values.
4686 So, for a partial specialization, or for a function template
4687 (in C++98/C++03), we look at all of them. */
4690 /* But, for a primary class template that is not a partial
4691 specialization we look at all template parameters except the
4693 parms = TREE_CHAIN (parms);
4695 /* Figure out what error message to issue. */
4696 if (is_friend_decl == 2)
4697 msg = G_("default template arguments may not be used in function template "
4698 "friend re-declaration");
4699 else if (is_friend_decl)
4700 msg = G_("default template arguments may not be used in function template "
4701 "friend declarations");
4702 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4703 msg = G_("default template arguments may not be used in function templates "
4704 "without -std=c++11 or -std=gnu++11");
4705 else if (is_partial)
4706 msg = G_("default template arguments may not be used in "
4707 "partial specializations");
4709 msg = G_("default argument for template parameter for class enclosing %qD");
4711 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4712 /* If we're inside a class definition, there's no need to
4713 examine the parameters to the class itself. On the one
4714 hand, they will be checked when the class is defined, and,
4715 on the other, default arguments are valid in things like:
4716 template <class T = double>
4717 struct S { template <class U> void f(U); };
4718 Here the default argument for `S' has no bearing on the
4719 declaration of `f'. */
4720 last_level_to_check = template_class_depth (current_class_type) + 1;
4722 /* Check everything. */
4723 last_level_to_check = 0;
4725 for (parm_level = parms;
4726 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4727 parm_level = TREE_CHAIN (parm_level))
4729 tree inner_parms = TREE_VALUE (parm_level);
4733 ntparms = TREE_VEC_LENGTH (inner_parms);
4734 for (i = 0; i < ntparms; ++i)
4736 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4739 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4744 if (is_friend_decl == 2)
4751 /* Clear out the default argument so that we are not
4753 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4757 /* At this point, if we're still interested in issuing messages,
4758 they must apply to classes surrounding the object declared. */
4760 msg = G_("default argument for template parameter for class "
4767 /* Worker for push_template_decl_real, called via
4768 for_each_template_parm. DATA is really an int, indicating the
4769 level of the parameters we are interested in. If T is a template
4770 parameter of that level, return nonzero. */
4773 template_parm_this_level_p (tree t, void* data)
4775 int this_level = *(int *)data;
4778 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4779 level = TEMPLATE_PARM_LEVEL (t);
4781 level = TEMPLATE_TYPE_LEVEL (t);
4782 return level == this_level;
4785 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4786 parameters given by current_template_args, or reuses a
4787 previously existing one, if appropriate. Returns the DECL, or an
4788 equivalent one, if it is replaced via a call to duplicate_decls.
4790 If IS_FRIEND is true, DECL is a friend declaration. */
4793 push_template_decl_real (tree decl, bool is_friend)
4801 int new_template_p = 0;
4802 /* True if the template is a member template, in the sense of
4804 bool member_template_p = false;
4806 if (decl == error_mark_node || !current_template_parms)
4807 return error_mark_node;
4809 /* See if this is a partial specialization. */
4810 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4811 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4812 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4814 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4818 /* For a friend, we want the context of the friend function, not
4819 the type of which it is a friend. */
4820 ctx = CP_DECL_CONTEXT (decl);
4821 else if (CP_DECL_CONTEXT (decl)
4822 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4823 /* In the case of a virtual function, we want the class in which
4825 ctx = CP_DECL_CONTEXT (decl);
4827 /* Otherwise, if we're currently defining some class, the DECL
4828 is assumed to be a member of the class. */
4829 ctx = current_scope ();
4831 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4834 if (!DECL_CONTEXT (decl))
4835 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4837 /* See if this is a primary template. */
4838 if (is_friend && ctx)
4839 /* A friend template that specifies a class context, i.e.
4840 template <typename T> friend void A<T>::f();
4844 primary = template_parm_scope_p ();
4848 if (DECL_CLASS_SCOPE_P (decl))
4849 member_template_p = true;
4850 if (TREE_CODE (decl) == TYPE_DECL
4851 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4853 error ("template class without a name");
4854 return error_mark_node;
4856 else if (TREE_CODE (decl) == FUNCTION_DECL)
4858 if (DECL_DESTRUCTOR_P (decl))
4862 A destructor shall not be a member template. */
4863 error ("destructor %qD declared as member template", decl);
4864 return error_mark_node;
4866 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4867 && (!prototype_p (TREE_TYPE (decl))
4868 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4869 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4870 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4871 == void_list_node)))
4873 /* [basic.stc.dynamic.allocation]
4875 An allocation function can be a function
4876 template. ... Template allocation functions shall
4877 have two or more parameters. */
4878 error ("invalid template declaration of %qD", decl);
4879 return error_mark_node;
4882 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4883 && CLASS_TYPE_P (TREE_TYPE (decl)))
4885 else if (TREE_CODE (decl) == TYPE_DECL
4886 && TYPE_DECL_ALIAS_P (decl))
4887 /* alias-declaration */
4888 gcc_assert (!DECL_ARTIFICIAL (decl));
4891 error ("template declaration of %q#D", decl);
4892 return error_mark_node;
4896 /* Check to see that the rules regarding the use of default
4897 arguments are not being violated. */
4898 check_default_tmpl_args (decl, current_template_parms,
4899 primary, is_partial, /*is_friend_decl=*/0);
4901 /* Ensure that there are no parameter packs in the type of this
4902 declaration that have not been expanded. */
4903 if (TREE_CODE (decl) == FUNCTION_DECL)
4905 /* Check each of the arguments individually to see if there are
4906 any bare parameter packs. */
4907 tree type = TREE_TYPE (decl);
4908 tree arg = DECL_ARGUMENTS (decl);
4909 tree argtype = TYPE_ARG_TYPES (type);
4911 while (arg && argtype)
4913 if (!FUNCTION_PARAMETER_PACK_P (arg)
4914 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4916 /* This is a PARM_DECL that contains unexpanded parameter
4917 packs. We have already complained about this in the
4918 check_for_bare_parameter_packs call, so just replace
4919 these types with ERROR_MARK_NODE. */
4920 TREE_TYPE (arg) = error_mark_node;
4921 TREE_VALUE (argtype) = error_mark_node;
4924 arg = DECL_CHAIN (arg);
4925 argtype = TREE_CHAIN (argtype);
4928 /* Check for bare parameter packs in the return type and the
4929 exception specifiers. */
4930 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4931 /* Errors were already issued, set return type to int
4932 as the frontend doesn't expect error_mark_node as
4934 TREE_TYPE (type) = integer_type_node;
4935 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4936 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4938 else if (check_for_bare_parameter_packs ((TREE_CODE (decl) == TYPE_DECL
4939 && TYPE_DECL_ALIAS_P (decl))
4940 ? DECL_ORIGINAL_TYPE (decl)
4941 : TREE_TYPE (decl)))
4943 TREE_TYPE (decl) = error_mark_node;
4944 return error_mark_node;
4948 return process_partial_specialization (decl);
4950 args = current_template_args ();
4953 || TREE_CODE (ctx) == FUNCTION_DECL
4954 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4955 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4957 if (DECL_LANG_SPECIFIC (decl)
4958 && DECL_TEMPLATE_INFO (decl)
4959 && DECL_TI_TEMPLATE (decl))
4960 tmpl = DECL_TI_TEMPLATE (decl);
4961 /* If DECL is a TYPE_DECL for a class-template, then there won't
4962 be DECL_LANG_SPECIFIC. The information equivalent to
4963 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4964 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4965 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4966 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4968 /* Since a template declaration already existed for this
4969 class-type, we must be redeclaring it here. Make sure
4970 that the redeclaration is valid. */
4971 redeclare_class_template (TREE_TYPE (decl),
4972 current_template_parms);
4973 /* We don't need to create a new TEMPLATE_DECL; just use the
4974 one we already had. */
4975 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4979 tmpl = build_template_decl (decl, current_template_parms,
4983 if (DECL_LANG_SPECIFIC (decl)
4984 && DECL_TEMPLATE_SPECIALIZATION (decl))
4986 /* A specialization of a member template of a template
4988 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4989 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4990 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4996 tree a, t, current, parms;
4998 tree tinfo = get_template_info (decl);
5002 error ("template definition of non-template %q#D", decl);
5003 return error_mark_node;
5006 tmpl = TI_TEMPLATE (tinfo);
5008 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
5009 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
5010 && DECL_TEMPLATE_SPECIALIZATION (decl)
5011 && DECL_MEMBER_TEMPLATE_P (tmpl))
5015 /* The declaration is a specialization of a member
5016 template, declared outside the class. Therefore, the
5017 innermost template arguments will be NULL, so we
5018 replace them with the arguments determined by the
5019 earlier call to check_explicit_specialization. */
5020 args = DECL_TI_ARGS (decl);
5023 = build_template_decl (decl, current_template_parms,
5025 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
5026 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
5027 DECL_TI_TEMPLATE (decl) = new_tmpl;
5028 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
5029 DECL_TEMPLATE_INFO (new_tmpl)
5030 = build_template_info (tmpl, args);
5032 register_specialization (new_tmpl,
5033 most_general_template (tmpl),
5039 /* Make sure the template headers we got make sense. */
5041 parms = DECL_TEMPLATE_PARMS (tmpl);
5042 i = TMPL_PARMS_DEPTH (parms);
5043 if (TMPL_ARGS_DEPTH (args) != i)
5045 error ("expected %d levels of template parms for %q#D, got %d",
5046 i, decl, TMPL_ARGS_DEPTH (args));
5049 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
5051 a = TMPL_ARGS_LEVEL (args, i);
5052 t = INNERMOST_TEMPLATE_PARMS (parms);
5054 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
5056 if (current == decl)
5057 error ("got %d template parameters for %q#D",
5058 TREE_VEC_LENGTH (a), decl);
5060 error ("got %d template parameters for %q#T",
5061 TREE_VEC_LENGTH (a), current);
5062 error (" but %d required", TREE_VEC_LENGTH (t));
5063 return error_mark_node;
5066 if (current == decl)
5068 else if (current == NULL_TREE)
5069 /* Can happen in erroneous input. */
5072 current = (TYPE_P (current)
5073 ? TYPE_CONTEXT (current)
5074 : DECL_CONTEXT (current));
5077 /* Check that the parms are used in the appropriate qualifying scopes
5078 in the declarator. */
5079 if (!comp_template_args
5081 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
5084 template arguments to %qD do not match original template %qD",
5085 decl, DECL_TEMPLATE_RESULT (tmpl));
5086 if (!uses_template_parms (TI_ARGS (tinfo)))
5087 inform (input_location, "use template<> for an explicit specialization");
5088 /* Avoid crash in import_export_decl. */
5089 DECL_INTERFACE_KNOWN (decl) = 1;
5090 return error_mark_node;
5094 DECL_TEMPLATE_RESULT (tmpl) = decl;
5095 TREE_TYPE (tmpl) = TREE_TYPE (decl);
5097 /* Push template declarations for global functions and types. Note
5098 that we do not try to push a global template friend declared in a
5099 template class; such a thing may well depend on the template
5100 parameters of the class. */
5101 if (new_template_p && !ctx
5102 && !(is_friend && template_class_depth (current_class_type) > 0))
5104 tmpl = pushdecl_namespace_level (tmpl, is_friend);
5105 if (tmpl == error_mark_node)
5106 return error_mark_node;
5108 /* Hide template friend classes that haven't been declared yet. */
5109 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
5111 DECL_ANTICIPATED (tmpl) = 1;
5112 DECL_FRIEND_P (tmpl) = 1;
5118 tree parms = DECL_TEMPLATE_PARMS (tmpl);
5121 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
5122 if (DECL_CONV_FN_P (tmpl))
5124 int depth = TMPL_PARMS_DEPTH (parms);
5126 /* It is a conversion operator. See if the type converted to
5127 depends on innermost template operands. */
5129 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
5131 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
5134 /* Give template template parms a DECL_CONTEXT of the template
5135 for which they are a parameter. */
5136 parms = INNERMOST_TEMPLATE_PARMS (parms);
5137 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
5139 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5140 if (TREE_CODE (parm) == TEMPLATE_DECL)
5141 DECL_CONTEXT (parm) = tmpl;
5145 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
5146 back to its most general template. If TMPL is a specialization,
5147 ARGS may only have the innermost set of arguments. Add the missing
5148 argument levels if necessary. */
5149 if (DECL_TEMPLATE_INFO (tmpl))
5150 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
5152 info = build_template_info (tmpl, args);
5154 if (DECL_IMPLICIT_TYPEDEF_P (decl))
5155 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
5158 if (primary && !DECL_LANG_SPECIFIC (decl))
5159 retrofit_lang_decl (decl);
5160 if (DECL_LANG_SPECIFIC (decl))
5161 DECL_TEMPLATE_INFO (decl) = info;
5164 return DECL_TEMPLATE_RESULT (tmpl);
5168 push_template_decl (tree decl)
5170 return push_template_decl_real (decl, false);
5173 /* Called when a class template TYPE is redeclared with the indicated
5174 template PARMS, e.g.:
5176 template <class T> struct S;
5177 template <class T> struct S {}; */
5180 redeclare_class_template (tree type, tree parms)
5186 if (!TYPE_TEMPLATE_INFO (type))
5188 error ("%qT is not a template type", type);
5192 tmpl = TYPE_TI_TEMPLATE (type);
5193 if (!PRIMARY_TEMPLATE_P (tmpl))
5194 /* The type is nested in some template class. Nothing to worry
5195 about here; there are no new template parameters for the nested
5201 error ("template specifiers not specified in declaration of %qD",
5206 parms = INNERMOST_TEMPLATE_PARMS (parms);
5207 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
5209 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
5211 error_n (input_location, TREE_VEC_LENGTH (parms),
5212 "redeclared with %d template parameter",
5213 "redeclared with %d template parameters",
5214 TREE_VEC_LENGTH (parms));
5215 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
5216 "previous declaration %q+D used %d template parameter",
5217 "previous declaration %q+D used %d template parameters",
5218 tmpl, TREE_VEC_LENGTH (tmpl_parms));
5222 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
5229 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
5230 || TREE_VEC_ELT (parms, i) == error_mark_node)
5233 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
5234 if (tmpl_parm == error_mark_node)
5237 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
5238 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
5239 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
5241 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5243 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5244 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5245 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5246 || (TREE_CODE (tmpl_parm) != PARM_DECL
5247 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5248 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5249 || (TREE_CODE (tmpl_parm) == PARM_DECL
5250 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5251 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5253 error ("template parameter %q+#D", tmpl_parm);
5254 error ("redeclared here as %q#D", parm);
5258 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5260 /* We have in [temp.param]:
5262 A template-parameter may not be given default arguments
5263 by two different declarations in the same scope. */
5264 error_at (input_location, "redefinition of default argument for %q#D", parm);
5265 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5266 "original definition appeared here");
5270 if (parm_default != NULL_TREE)
5271 /* Update the previous template parameters (which are the ones
5272 that will really count) with the new default value. */
5273 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5274 else if (tmpl_default != NULL_TREE)
5275 /* Update the new parameters, too; they'll be used as the
5276 parameters for any members. */
5277 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5283 /* Simplify EXPR if it is a non-dependent expression. Returns the
5284 (possibly simplified) expression. */
5287 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5289 if (expr == NULL_TREE)
5292 /* If we're in a template, but EXPR isn't value dependent, simplify
5293 it. We're supposed to treat:
5295 template <typename T> void f(T[1 + 1]);
5296 template <typename T> void f(T[2]);
5298 as two declarations of the same function, for example. */
5299 if (processing_template_decl
5300 && !type_dependent_expression_p (expr)
5301 && potential_constant_expression (expr)
5302 && !value_dependent_expression_p (expr))
5304 HOST_WIDE_INT saved_processing_template_decl;
5306 saved_processing_template_decl = processing_template_decl;
5307 processing_template_decl = 0;
5308 expr = tsubst_copy_and_build (expr,
5311 /*in_decl=*/NULL_TREE,
5312 /*function_p=*/false,
5313 /*integral_constant_expression_p=*/true);
5314 processing_template_decl = saved_processing_template_decl;
5320 fold_non_dependent_expr (tree expr)
5322 return fold_non_dependent_expr_sfinae (expr, tf_error);
5325 /* Return TRUE iff T is a type alias, a TEMPLATE_DECL for an alias
5326 template declaration, or a TYPE_DECL for an alias declaration. */
5329 alias_type_or_template_p (tree t)
5333 return ((TREE_CODE (t) == TYPE_DECL && TYPE_DECL_ALIAS_P (t))
5336 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
5337 || DECL_ALIAS_TEMPLATE_P (t));
5340 /* Return TRUE iff is a specialization of an alias template. */
5343 alias_template_specialization_p (tree t)
5347 return (primary_template_instantiation_p (t)
5348 && DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (t)));
5351 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5352 must be a function or a pointer-to-function type, as specified
5353 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5354 and check that the resulting function has external linkage. */
5357 convert_nontype_argument_function (tree type, tree expr)
5361 linkage_kind linkage;
5363 fn = instantiate_type (type, fns, tf_none);
5364 if (fn == error_mark_node)
5365 return error_mark_node;
5368 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5369 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5370 if (BASELINK_P (fn_no_ptr))
5371 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5373 /* [temp.arg.nontype]/1
5375 A template-argument for a non-type, non-template template-parameter
5378 -- the address of an object or function with external [C++11: or
5379 internal] linkage. */
5380 linkage = decl_linkage (fn_no_ptr);
5381 if (cxx_dialect >= cxx0x ? linkage == lk_none : linkage != lk_external)
5383 if (cxx_dialect >= cxx0x)
5384 error ("%qE is not a valid template argument for type %qT "
5385 "because %qD has no linkage",
5386 expr, type, fn_no_ptr);
5388 error ("%qE is not a valid template argument for type %qT "
5389 "because %qD does not have external linkage",
5390 expr, type, fn_no_ptr);
5397 /* Subroutine of convert_nontype_argument.
5398 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5399 Emit an error otherwise. */
5402 check_valid_ptrmem_cst_expr (tree type, tree expr,
5403 tsubst_flags_t complain)
5406 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5408 if (cxx_dialect >= cxx0x && null_member_pointer_value_p (expr))
5410 if (complain & tf_error)
5412 error ("%qE is not a valid template argument for type %qT",
5414 error ("it must be a pointer-to-member of the form %<&X::Y%>");
5419 /* Returns TRUE iff the address of OP is value-dependent.
5421 14.6.2.4 [temp.dep.temp]:
5422 A non-integral non-type template-argument is dependent if its type is
5423 dependent or it has either of the following forms
5426 and contains a nested-name-specifier which specifies a class-name that
5427 names a dependent type.
5429 We generalize this to just say that the address of a member of a
5430 dependent class is value-dependent; the above doesn't cover the
5431 address of a static data member named with an unqualified-id. */
5434 has_value_dependent_address (tree op)
5436 /* We could use get_inner_reference here, but there's no need;
5437 this is only relevant for template non-type arguments, which
5438 can only be expressed as &id-expression. */
5441 tree ctx = CP_DECL_CONTEXT (op);
5442 if (TYPE_P (ctx) && dependent_type_p (ctx))
5449 /* The next set of functions are used for providing helpful explanatory
5450 diagnostics for failed overload resolution. Their messages should be
5451 indented by two spaces for consistency with the messages in
5455 unify_success (bool explain_p ATTRIBUTE_UNUSED)
5461 unify_parameter_deduction_failure (bool explain_p, tree parm)
5464 inform (input_location,
5465 " couldn't deduce template parameter %qD", parm);
5470 unify_invalid (bool explain_p ATTRIBUTE_UNUSED)
5476 unify_cv_qual_mismatch (bool explain_p, tree parm, tree arg)
5479 inform (input_location,
5480 " types %qT and %qT have incompatible cv-qualifiers",
5486 unify_type_mismatch (bool explain_p, tree parm, tree arg)
5489 inform (input_location, " mismatched types %qT and %qT", parm, arg);
5494 unify_parameter_pack_mismatch (bool explain_p, tree parm, tree arg)
5497 inform (input_location,
5498 " template parameter %qD is not a parameter pack, but "
5505 unify_ptrmem_cst_mismatch (bool explain_p, tree parm, tree arg)
5508 inform (input_location,
5509 " template argument %qE does not match "
5510 "pointer-to-member constant %qE",
5516 unify_expression_unequal (bool explain_p, tree parm, tree arg)
5519 inform (input_location, " %qE is not equivalent to %qE", parm, arg);
5524 unify_parameter_pack_inconsistent (bool explain_p, tree old_arg, tree new_arg)
5527 inform (input_location,
5528 " inconsistent parameter pack deduction with %qT and %qT",
5534 unify_inconsistency (bool explain_p, tree parm, tree first, tree second)
5539 inform (input_location,
5540 " deduced conflicting types for parameter %qT (%qT and %qT)",
5541 parm, first, second);
5543 inform (input_location,
5544 " deduced conflicting values for non-type parameter "
5545 "%qE (%qE and %qE)", parm, first, second);
5551 unify_vla_arg (bool explain_p, tree arg)
5554 inform (input_location,
5555 " variable-sized array type %qT is not "
5556 "a valid template argument",
5562 unify_method_type_error (bool explain_p, tree arg)
5565 inform (input_location,
5566 " member function type %qT is not a valid template argument",
5572 unify_arity (bool explain_p, int have, int wanted)
5575 inform_n (input_location, wanted,
5576 " candidate expects %d argument, %d provided",
5577 " candidate expects %d arguments, %d provided",
5583 unify_too_many_arguments (bool explain_p, int have, int wanted)
5585 return unify_arity (explain_p, have, wanted);
5589 unify_too_few_arguments (bool explain_p, int have, int wanted)
5591 return unify_arity (explain_p, have, wanted);
5595 unify_arg_conversion (bool explain_p, tree to_type,
5596 tree from_type, tree arg)
5599 inform (input_location, " cannot convert %qE (type %qT) to type %qT",
5600 arg, from_type, to_type);
5605 unify_no_common_base (bool explain_p, enum template_base_result r,
5606 tree parm, tree arg)
5611 case tbr_ambiguous_baseclass:
5612 inform (input_location, " %qT is an ambiguous base class of %qT",
5616 inform (input_location, " %qT is not derived from %qT", arg, parm);
5623 unify_inconsistent_template_template_parameters (bool explain_p)
5626 inform (input_location,
5627 " template parameters of a template template argument are "
5628 "inconsistent with other deduced template arguments");
5633 unify_template_deduction_failure (bool explain_p, tree parm, tree arg)
5636 inform (input_location,
5637 " can't deduce a template for %qT from non-template type %qT",
5643 unify_template_argument_mismatch (bool explain_p, tree parm, tree arg)
5646 inform (input_location,
5647 " template argument %qE does not match %qD", arg, parm);
5652 unify_overload_resolution_failure (bool explain_p, tree arg)
5655 inform (input_location,
5656 " could not resolve address from overloaded function %qE",
5661 /* Attempt to convert the non-type template parameter EXPR to the
5662 indicated TYPE. If the conversion is successful, return the
5663 converted value. If the conversion is unsuccessful, return
5664 NULL_TREE if we issued an error message, or error_mark_node if we
5665 did not. We issue error messages for out-and-out bad template
5666 parameters, but not simply because the conversion failed, since we
5667 might be just trying to do argument deduction. Both TYPE and EXPR
5668 must be non-dependent.
5670 The conversion follows the special rules described in
5671 [temp.arg.nontype], and it is much more strict than an implicit
5674 This function is called twice for each template argument (see
5675 lookup_template_class for a more accurate description of this
5676 problem). This means that we need to handle expressions which
5677 are not valid in a C++ source, but can be created from the
5678 first call (for instance, casts to perform conversions). These
5679 hacks can go away after we fix the double coercion problem. */
5682 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5686 /* Detect immediately string literals as invalid non-type argument.
5687 This special-case is not needed for correctness (we would easily
5688 catch this later), but only to provide better diagnostic for this
5689 common user mistake. As suggested by DR 100, we do not mention
5690 linkage issues in the diagnostic as this is not the point. */
5691 /* FIXME we're making this OK. */
5692 if (TREE_CODE (expr) == STRING_CST)
5694 if (complain & tf_error)
5695 error ("%qE is not a valid template argument for type %qT "
5696 "because string literals can never be used in this context",
5701 /* Add the ADDR_EXPR now for the benefit of
5702 value_dependent_expression_p. */
5703 if (TYPE_PTROBV_P (type)
5704 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE)
5705 expr = decay_conversion (expr);
5707 /* If we are in a template, EXPR may be non-dependent, but still
5708 have a syntactic, rather than semantic, form. For example, EXPR
5709 might be a SCOPE_REF, rather than the VAR_DECL to which the
5710 SCOPE_REF refers. Preserving the qualifying scope is necessary
5711 so that access checking can be performed when the template is
5712 instantiated -- but here we need the resolved form so that we can
5713 convert the argument. */
5714 if (TYPE_REF_OBJ_P (type)
5715 && has_value_dependent_address (expr))
5716 /* If we want the address and it's value-dependent, don't fold. */;
5717 else if (!type_unknown_p (expr))
5718 expr = fold_non_dependent_expr_sfinae (expr, complain);
5719 if (error_operand_p (expr))
5720 return error_mark_node;
5721 expr_type = TREE_TYPE (expr);
5722 if (TREE_CODE (type) == REFERENCE_TYPE)
5723 expr = mark_lvalue_use (expr);
5725 expr = mark_rvalue_use (expr);
5727 /* 14.3.2/5: The null pointer{,-to-member} conversion is applied
5728 to a non-type argument of "nullptr". */
5729 if (expr == nullptr_node
5730 && (TYPE_PTR_P (type) || TYPE_PTR_TO_MEMBER_P (type)))
5731 expr = convert (type, expr);
5733 /* In C++11, integral or enumeration non-type template arguments can be
5734 arbitrary constant expressions. Pointer and pointer to
5735 member arguments can be general constant expressions that evaluate
5736 to a null value, but otherwise still need to be of a specific form. */
5737 if (cxx_dialect >= cxx0x)
5739 if (TREE_CODE (expr) == PTRMEM_CST)
5740 /* A PTRMEM_CST is already constant, and a valid template
5741 argument for a parameter of pointer to member type, we just want
5742 to leave it in that form rather than lower it to a
5744 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5745 expr = maybe_constant_value (expr);
5746 else if (TYPE_PTR_P (type)
5747 || TYPE_PTR_TO_MEMBER_P (type))
5749 tree folded = maybe_constant_value (expr);
5750 if (TYPE_PTR_P (type) ? integer_zerop (folded)
5751 : null_member_pointer_value_p (folded))
5756 /* HACK: Due to double coercion, we can get a
5757 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5758 which is the tree that we built on the first call (see
5759 below when coercing to reference to object or to reference to
5760 function). We just strip everything and get to the arg.
5761 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5763 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5765 tree probe_type, probe = expr;
5766 if (REFERENCE_REF_P (probe))
5767 probe = TREE_OPERAND (probe, 0);
5768 probe_type = TREE_TYPE (probe);
5769 if (TREE_CODE (probe) == NOP_EXPR)
5771 /* ??? Maybe we could use convert_from_reference here, but we
5772 would need to relax its constraints because the NOP_EXPR
5773 could actually change the type to something more cv-qualified,
5774 and this is not folded by convert_from_reference. */
5775 tree addr = TREE_OPERAND (probe, 0);
5776 gcc_assert (TREE_CODE (probe_type) == REFERENCE_TYPE);
5777 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
5778 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
5779 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5780 (TREE_TYPE (probe_type),
5781 TREE_TYPE (TREE_TYPE (addr))));
5783 expr = TREE_OPERAND (addr, 0);
5784 expr_type = TREE_TYPE (expr);
5788 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5789 parameter is a pointer to object, through decay and
5790 qualification conversion. Let's strip everything. */
5791 else if (TREE_CODE (expr) == NOP_EXPR && TYPE_PTROBV_P (type))
5794 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5795 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5796 /* Skip the ADDR_EXPR only if it is part of the decay for
5797 an array. Otherwise, it is part of the original argument
5798 in the source code. */
5799 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5800 expr = TREE_OPERAND (expr, 0);
5801 expr_type = TREE_TYPE (expr);
5804 /* [temp.arg.nontype]/5, bullet 1
5806 For a non-type template-parameter of integral or enumeration type,
5807 integral promotions (_conv.prom_) and integral conversions
5808 (_conv.integral_) are applied. */
5809 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5811 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5812 t = maybe_constant_value (t);
5813 if (t != error_mark_node)
5816 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5817 return error_mark_node;
5819 /* Notice that there are constant expressions like '4 % 0' which
5820 do not fold into integer constants. */
5821 if (TREE_CODE (expr) != INTEGER_CST)
5823 if (complain & tf_error)
5825 int errs = errorcount, warns = warningcount;
5826 if (processing_template_decl
5827 && !require_potential_constant_expression (expr))
5829 expr = cxx_constant_value (expr);
5830 if (errorcount > errs || warningcount > warns)
5831 inform (EXPR_LOC_OR_HERE (expr),
5832 "in template argument for type %qT ", type);
5833 if (expr == error_mark_node)
5835 /* else cxx_constant_value complained but gave us
5836 a real constant, so go ahead. */
5837 gcc_assert (TREE_CODE (expr) == INTEGER_CST);
5843 /* [temp.arg.nontype]/5, bullet 2
5845 For a non-type template-parameter of type pointer to object,
5846 qualification conversions (_conv.qual_) and the array-to-pointer
5847 conversion (_conv.array_) are applied. */
5848 else if (TYPE_PTROBV_P (type))
5850 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5852 A template-argument for a non-type, non-template template-parameter
5853 shall be one of: [...]
5855 -- the name of a non-type template-parameter;
5856 -- the address of an object or function with external linkage, [...]
5857 expressed as "& id-expression" where the & is optional if the name
5858 refers to a function or array, or if the corresponding
5859 template-parameter is a reference.
5861 Here, we do not care about functions, as they are invalid anyway
5862 for a parameter of type pointer-to-object. */
5864 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5865 /* Non-type template parameters are OK. */
5867 else if (cxx_dialect >= cxx0x && integer_zerop (expr))
5868 /* Null pointer values are OK in C++11. */;
5869 else if (TREE_CODE (expr) != ADDR_EXPR
5870 && TREE_CODE (expr_type) != ARRAY_TYPE)
5872 if (TREE_CODE (expr) == VAR_DECL)
5874 error ("%qD is not a valid template argument "
5875 "because %qD is a variable, not the address of "
5880 /* Other values, like integer constants, might be valid
5881 non-type arguments of some other type. */
5882 return error_mark_node;
5888 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5889 ? TREE_OPERAND (expr, 0) : expr);
5890 if (TREE_CODE (decl) != VAR_DECL)
5892 error ("%qE is not a valid template argument of type %qT "
5893 "because %qE is not a variable",
5897 else if (cxx_dialect < cxx0x && !DECL_EXTERNAL_LINKAGE_P (decl))
5899 error ("%qE is not a valid template argument of type %qT "
5900 "because %qD does not have external linkage",
5904 else if (cxx_dialect >= cxx0x && decl_linkage (decl) == lk_none)
5906 error ("%qE is not a valid template argument of type %qT "
5907 "because %qD has no linkage",
5913 expr = decay_conversion (expr);
5914 if (expr == error_mark_node)
5915 return error_mark_node;
5917 expr = perform_qualification_conversions (type, expr);
5918 if (expr == error_mark_node)
5919 return error_mark_node;
5921 /* [temp.arg.nontype]/5, bullet 3
5923 For a non-type template-parameter of type reference to object, no
5924 conversions apply. The type referred to by the reference may be more
5925 cv-qualified than the (otherwise identical) type of the
5926 template-argument. The template-parameter is bound directly to the
5927 template-argument, which must be an lvalue. */
5928 else if (TYPE_REF_OBJ_P (type))
5930 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5932 return error_mark_node;
5934 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5936 error ("%qE is not a valid template argument for type %qT "
5937 "because of conflicts in cv-qualification", expr, type);
5941 if (!real_lvalue_p (expr))
5943 error ("%qE is not a valid template argument for type %qT "
5944 "because it is not an lvalue", expr, type);
5948 /* [temp.arg.nontype]/1
5950 A template-argument for a non-type, non-template template-parameter
5951 shall be one of: [...]
5953 -- the address of an object or function with external linkage. */
5954 if (TREE_CODE (expr) == INDIRECT_REF
5955 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5957 expr = TREE_OPERAND (expr, 0);
5960 error ("%q#D is not a valid template argument for type %qT "
5961 "because a reference variable does not have a constant "
5962 "address", expr, type);
5969 error ("%qE is not a valid template argument for type %qT "
5970 "because it is not an object with external linkage",
5975 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5977 error ("%qE is not a valid template argument for type %qT "
5978 "because object %qD has not external linkage",
5983 expr = build_nop (type, build_address (expr));
5985 /* [temp.arg.nontype]/5, bullet 4
5987 For a non-type template-parameter of type pointer to function, only
5988 the function-to-pointer conversion (_conv.func_) is applied. If the
5989 template-argument represents a set of overloaded functions (or a
5990 pointer to such), the matching function is selected from the set
5992 else if (TYPE_PTRFN_P (type))
5994 /* If the argument is a template-id, we might not have enough
5995 context information to decay the pointer. */
5996 if (!type_unknown_p (expr_type))
5998 expr = decay_conversion (expr);
5999 if (expr == error_mark_node)
6000 return error_mark_node;
6003 if (cxx_dialect >= cxx0x && integer_zerop (expr))
6004 /* Null pointer values are OK in C++11. */
6005 return perform_qualification_conversions (type, expr);
6007 expr = convert_nontype_argument_function (type, expr);
6008 if (!expr || expr == error_mark_node)
6011 if (TREE_CODE (expr) != ADDR_EXPR)
6013 error ("%qE is not a valid template argument for type %qT", expr, type);
6014 error ("it must be the address of a function with external linkage");
6018 /* [temp.arg.nontype]/5, bullet 5
6020 For a non-type template-parameter of type reference to function, no
6021 conversions apply. If the template-argument represents a set of
6022 overloaded functions, the matching function is selected from the set
6024 else if (TYPE_REFFN_P (type))
6026 if (TREE_CODE (expr) == ADDR_EXPR)
6028 error ("%qE is not a valid template argument for type %qT "
6029 "because it is a pointer", expr, type);
6030 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
6034 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
6035 if (!expr || expr == error_mark_node)
6038 expr = build_nop (type, build_address (expr));
6040 /* [temp.arg.nontype]/5, bullet 6
6042 For a non-type template-parameter of type pointer to member function,
6043 no conversions apply. If the template-argument represents a set of
6044 overloaded member functions, the matching member function is selected
6045 from the set (_over.over_). */
6046 else if (TYPE_PTRMEMFUNC_P (type))
6048 expr = instantiate_type (type, expr, tf_none);
6049 if (expr == error_mark_node)
6050 return error_mark_node;
6052 /* [temp.arg.nontype] bullet 1 says the pointer to member
6053 expression must be a pointer-to-member constant. */
6054 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
6055 return error_mark_node;
6057 /* There is no way to disable standard conversions in
6058 resolve_address_of_overloaded_function (called by
6059 instantiate_type). It is possible that the call succeeded by
6060 converting &B::I to &D::I (where B is a base of D), so we need
6061 to reject this conversion here.
6063 Actually, even if there was a way to disable standard conversions,
6064 it would still be better to reject them here so that we can
6065 provide a superior diagnostic. */
6066 if (!same_type_p (TREE_TYPE (expr), type))
6068 error ("%qE is not a valid template argument for type %qT "
6069 "because it is of type %qT", expr, type,
6071 /* If we are just one standard conversion off, explain. */
6072 if (can_convert (type, TREE_TYPE (expr)))
6073 inform (input_location,
6074 "standard conversions are not allowed in this context");
6078 /* [temp.arg.nontype]/5, bullet 7
6080 For a non-type template-parameter of type pointer to data member,
6081 qualification conversions (_conv.qual_) are applied. */
6082 else if (TYPE_PTRMEM_P (type))
6084 /* [temp.arg.nontype] bullet 1 says the pointer to member
6085 expression must be a pointer-to-member constant. */
6086 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
6087 return error_mark_node;
6089 expr = perform_qualification_conversions (type, expr);
6090 if (expr == error_mark_node)
6093 else if (NULLPTR_TYPE_P (type))
6095 if (expr != nullptr_node)
6097 error ("%qE is not a valid template argument for type %qT "
6098 "because it is of type %qT", expr, type, TREE_TYPE (expr));
6103 /* A template non-type parameter must be one of the above. */
6107 /* Sanity check: did we actually convert the argument to the
6109 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6110 (type, TREE_TYPE (expr)));
6114 /* Subroutine of coerce_template_template_parms, which returns 1 if
6115 PARM_PARM and ARG_PARM match using the rule for the template
6116 parameters of template template parameters. Both PARM and ARG are
6117 template parameters; the rest of the arguments are the same as for
6118 coerce_template_template_parms.
6121 coerce_template_template_parm (tree parm,
6123 tsubst_flags_t complain,
6127 if (arg == NULL_TREE || arg == error_mark_node
6128 || parm == NULL_TREE || parm == error_mark_node)
6131 if (TREE_CODE (arg) != TREE_CODE (parm))
6134 switch (TREE_CODE (parm))
6137 /* We encounter instantiations of templates like
6138 template <template <template <class> class> class TT>
6141 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6142 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6144 if (!coerce_template_template_parms
6145 (parmparm, argparm, complain, in_decl, outer_args))
6151 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
6152 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6153 /* Argument is a parameter pack but parameter is not. */
6158 /* The tsubst call is used to handle cases such as
6160 template <int> class C {};
6161 template <class T, template <T> class TT> class D {};
6164 i.e. the parameter list of TT depends on earlier parameters. */
6165 if (!uses_template_parms (TREE_TYPE (arg))
6167 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
6171 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
6172 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6173 /* Argument is a parameter pack but parameter is not. */
6186 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
6187 template template parameters. Both PARM_PARMS and ARG_PARMS are
6188 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
6191 Consider the example:
6192 template <class T> class A;
6193 template<template <class U> class TT> class B;
6195 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
6196 the parameters to A, and OUTER_ARGS contains A. */
6199 coerce_template_template_parms (tree parm_parms,
6201 tsubst_flags_t complain,
6205 int nparms, nargs, i;
6209 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
6210 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
6212 nparms = TREE_VEC_LENGTH (parm_parms);
6213 nargs = TREE_VEC_LENGTH (arg_parms);
6215 /* Determine whether we have a parameter pack at the end of the
6216 template template parameter's template parameter list. */
6217 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
6219 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
6221 if (parm == error_mark_node)
6224 switch (TREE_CODE (parm))
6228 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6233 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6243 && !(variadic_p && nargs >= nparms - 1))
6246 /* Check all of the template parameters except the parameter pack at
6247 the end (if any). */
6248 for (i = 0; i < nparms - variadic_p; ++i)
6250 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
6251 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6254 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6255 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6257 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6265 /* Check each of the template parameters in the template
6266 argument against the template parameter pack at the end of
6267 the template template parameter. */
6268 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
6271 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6273 for (; i < nargs; ++i)
6275 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6278 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6280 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6289 /* Verifies that the deduced template arguments (in TARGS) for the
6290 template template parameters (in TPARMS) represent valid bindings,
6291 by comparing the template parameter list of each template argument
6292 to the template parameter list of its corresponding template
6293 template parameter, in accordance with DR150. This
6294 routine can only be called after all template arguments have been
6295 deduced. It will return TRUE if all of the template template
6296 parameter bindings are okay, FALSE otherwise. */
6298 template_template_parm_bindings_ok_p (tree tparms, tree targs)
6300 int i, ntparms = TREE_VEC_LENGTH (tparms);
6303 /* We're dealing with template parms in this process. */
6304 ++processing_template_decl;
6306 targs = INNERMOST_TEMPLATE_ARGS (targs);
6308 for (i = 0; i < ntparms; ++i)
6310 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
6311 tree targ = TREE_VEC_ELT (targs, i);
6313 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
6315 tree packed_args = NULL_TREE;
6318 if (ARGUMENT_PACK_P (targ))
6320 /* Look inside the argument pack. */
6321 packed_args = ARGUMENT_PACK_ARGS (targ);
6322 len = TREE_VEC_LENGTH (packed_args);
6325 for (idx = 0; idx < len; ++idx)
6327 tree targ_parms = NULL_TREE;
6330 /* Extract the next argument from the argument
6332 targ = TREE_VEC_ELT (packed_args, idx);
6334 if (PACK_EXPANSION_P (targ))
6335 /* Look at the pattern of the pack expansion. */
6336 targ = PACK_EXPANSION_PATTERN (targ);
6338 /* Extract the template parameters from the template
6340 if (TREE_CODE (targ) == TEMPLATE_DECL)
6341 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
6342 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
6343 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
6345 /* Verify that we can coerce the template template
6346 parameters from the template argument to the template
6347 parameter. This requires an exact match. */
6349 && !coerce_template_template_parms
6350 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
6365 --processing_template_decl;
6369 /* Since type attributes aren't mangled, we need to strip them from
6370 template type arguments. */
6373 canonicalize_type_argument (tree arg, tsubst_flags_t complain)
6376 if (!arg || arg == error_mark_node || arg == TYPE_CANONICAL (arg))
6378 mv = TYPE_MAIN_VARIANT (arg);
6379 arg = strip_typedefs (arg);
6380 if (TYPE_ALIGN (arg) != TYPE_ALIGN (mv)
6381 || TYPE_ATTRIBUTES (arg) != TYPE_ATTRIBUTES (mv))
6383 if (complain & tf_warning)
6384 warning (0, "ignoring attributes on template argument %qT", arg);
6385 arg = build_aligned_type (arg, TYPE_ALIGN (mv));
6386 arg = cp_build_type_attribute_variant (arg, TYPE_ATTRIBUTES (mv));
6391 /* Convert the indicated template ARG as necessary to match the
6392 indicated template PARM. Returns the converted ARG, or
6393 error_mark_node if the conversion was unsuccessful. Error and
6394 warning messages are issued under control of COMPLAIN. This
6395 conversion is for the Ith parameter in the parameter list. ARGS is
6396 the full set of template arguments deduced so far. */
6399 convert_template_argument (tree parm,
6402 tsubst_flags_t complain,
6408 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
6410 if (TREE_CODE (arg) == TREE_LIST
6411 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
6413 /* The template argument was the name of some
6414 member function. That's usually
6415 invalid, but static members are OK. In any
6416 case, grab the underlying fields/functions
6417 and issue an error later if required. */
6418 orig_arg = TREE_VALUE (arg);
6419 TREE_TYPE (arg) = unknown_type_node;
6424 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
6425 requires_type = (TREE_CODE (parm) == TYPE_DECL
6426 || requires_tmpl_type);
6428 /* When determining whether an argument pack expansion is a template,
6429 look at the pattern. */
6430 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
6431 arg = PACK_EXPANSION_PATTERN (arg);
6433 /* Deal with an injected-class-name used as a template template arg. */
6434 if (requires_tmpl_type && CLASS_TYPE_P (arg))
6436 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
6437 if (TREE_CODE (t) == TEMPLATE_DECL)
6439 if (cxx_dialect >= cxx0x)
6440 /* OK under DR 1004. */;
6441 else if (complain & tf_warning_or_error)
6442 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD"
6443 " used as template template argument", TYPE_NAME (arg));
6444 else if (flag_pedantic_errors)
6452 ((TREE_CODE (arg) == TEMPLATE_DECL
6453 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
6454 || (requires_tmpl_type && TREE_CODE (arg) == TYPE_ARGUMENT_PACK)
6455 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6456 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
6459 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6460 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
6461 arg = TYPE_STUB_DECL (arg);
6463 is_type = TYPE_P (arg) || is_tmpl_type;
6465 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
6466 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
6468 if (TREE_CODE (TREE_OPERAND (arg, 1)) == BIT_NOT_EXPR)
6470 if (complain & tf_error)
6471 error ("invalid use of destructor %qE as a type", orig_arg);
6472 return error_mark_node;
6475 permerror (input_location,
6476 "to refer to a type member of a template parameter, "
6477 "use %<typename %E%>", orig_arg);
6479 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
6480 TREE_OPERAND (arg, 1),
6482 complain & tf_error);
6486 if (is_type != requires_type)
6490 if (complain & tf_error)
6492 error ("type/value mismatch at argument %d in template "
6493 "parameter list for %qD",
6496 error (" expected a constant of type %qT, got %qT",
6498 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6499 else if (requires_tmpl_type)
6500 error (" expected a class template, got %qE", orig_arg);
6502 error (" expected a type, got %qE", orig_arg);
6505 return error_mark_node;
6507 if (is_tmpl_type ^ requires_tmpl_type)
6509 if (in_decl && (complain & tf_error))
6511 error ("type/value mismatch at argument %d in template "
6512 "parameter list for %qD",
6515 error (" expected a type, got %qT", DECL_NAME (arg));
6517 error (" expected a class template, got %qT", orig_arg);
6519 return error_mark_node;
6524 if (requires_tmpl_type)
6526 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6528 else if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6529 /* The number of argument required is not known yet.
6530 Just accept it for now. */
6531 val = TREE_TYPE (arg);
6534 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6537 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6539 if (coerce_template_template_parms (parmparm, argparm,
6545 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6547 if (val != error_mark_node)
6549 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6550 val = TREE_TYPE (val);
6551 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6552 val = make_pack_expansion (val);
6557 if (in_decl && (complain & tf_error))
6559 error ("type/value mismatch at argument %d in "
6560 "template parameter list for %qD",
6562 error (" expected a template of type %qD, got %qT",
6566 val = error_mark_node;
6572 /* We only form one instance of each template specialization.
6573 Therefore, if we use a non-canonical variant (i.e., a
6574 typedef), any future messages referring to the type will use
6575 the typedef, which is confusing if those future uses do not
6576 themselves also use the typedef. */
6578 val = canonicalize_type_argument (val, complain);
6582 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6584 if (invalid_nontype_parm_type_p (t, complain))
6585 return error_mark_node;
6587 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6589 if (same_type_p (t, TREE_TYPE (orig_arg)))
6593 /* Not sure if this is reachable, but it doesn't hurt
6595 error ("type mismatch in nontype parameter pack");
6596 val = error_mark_node;
6599 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
6600 /* We used to call digest_init here. However, digest_init
6601 will report errors, which we don't want when complain
6602 is zero. More importantly, digest_init will try too
6603 hard to convert things: for example, `0' should not be
6604 converted to pointer type at this point according to
6605 the standard. Accepting this is not merely an
6606 extension, since deciding whether or not these
6607 conversions can occur is part of determining which
6608 function template to call, or whether a given explicit
6609 argument specification is valid. */
6610 val = convert_nontype_argument (t, orig_arg, complain);
6614 if (val == NULL_TREE)
6615 val = error_mark_node;
6616 else if (val == error_mark_node && (complain & tf_error))
6617 error ("could not convert template argument %qE to %qT", orig_arg, t);
6619 if (TREE_CODE (val) == SCOPE_REF)
6621 /* Strip typedefs from the SCOPE_REF. */
6622 tree type = canonicalize_type_argument (TREE_TYPE (val), complain);
6623 tree scope = canonicalize_type_argument (TREE_OPERAND (val, 0),
6625 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6626 QUALIFIED_NAME_IS_TEMPLATE (val));
6633 /* Coerces the remaining template arguments in INNER_ARGS (from
6634 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6635 Returns the coerced argument pack. PARM_IDX is the position of this
6636 parameter in the template parameter list. ARGS is the original
6637 template argument list. */
6639 coerce_template_parameter_pack (tree parms,
6647 tsubst_flags_t complain)
6649 tree parm = TREE_VEC_ELT (parms, parm_idx);
6650 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6653 tree packed_types = NULL_TREE;
6655 if (arg_idx > nargs)
6658 packed_args = make_tree_vec (nargs - arg_idx);
6660 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6661 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6663 /* When the template parameter is a non-type template
6664 parameter pack whose type uses parameter packs, we need
6665 to look at each of the template arguments
6666 separately. Build a vector of the types for these
6667 non-type template parameters in PACKED_TYPES. */
6669 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6670 packed_types = tsubst_pack_expansion (expansion, args,
6673 if (packed_types == error_mark_node)
6674 return error_mark_node;
6676 /* Check that we have the right number of arguments. */
6678 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6679 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6682 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6683 error ("wrong number of template arguments (%d, should be %d)",
6684 nargs, needed_parms);
6685 return error_mark_node;
6688 /* If we aren't able to check the actual arguments now
6689 (because they haven't been expanded yet), we can at least
6690 verify that all of the types used for the non-type
6691 template parameter pack are, in fact, valid for non-type
6692 template parameters. */
6694 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6696 int j, len = TREE_VEC_LENGTH (packed_types);
6697 for (j = 0; j < len; ++j)
6699 tree t = TREE_VEC_ELT (packed_types, j);
6700 if (invalid_nontype_parm_type_p (t, complain))
6701 return error_mark_node;
6706 /* Convert the remaining arguments, which will be a part of the
6707 parameter pack "parm". */
6708 for (; arg_idx < nargs; ++arg_idx)
6710 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6711 tree actual_parm = TREE_VALUE (parm);
6713 if (packed_types && !PACK_EXPANSION_P (arg))
6715 /* When we have a vector of types (corresponding to the
6716 non-type template parameter pack that uses parameter
6717 packs in its type, as mention above), and the
6718 argument is not an expansion (which expands to a
6719 currently unknown number of arguments), clone the
6720 parm and give it the next type in PACKED_TYPES. */
6721 actual_parm = copy_node (actual_parm);
6722 TREE_TYPE (actual_parm) =
6723 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6726 if (arg != error_mark_node)
6727 arg = convert_template_argument (actual_parm,
6728 arg, new_args, complain, parm_idx,
6730 if (arg == error_mark_node)
6732 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6735 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6736 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6737 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6740 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6741 TREE_TYPE (argument_pack)
6742 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6743 TREE_CONSTANT (argument_pack) = 1;
6746 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6747 #ifdef ENABLE_CHECKING
6748 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6749 TREE_VEC_LENGTH (packed_args));
6751 return argument_pack;
6754 /* Returns true if the template argument vector ARGS contains
6755 any pack expansions, false otherwise. */
6758 any_pack_expanson_args_p (tree args)
6762 for (i = 0; i < TREE_VEC_LENGTH (args); ++i)
6763 if (PACK_EXPANSION_P (TREE_VEC_ELT (args, i)))
6768 /* Convert all template arguments to their appropriate types, and
6769 return a vector containing the innermost resulting template
6770 arguments. If any error occurs, return error_mark_node. Error and
6771 warning messages are issued under control of COMPLAIN.
6773 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6774 for arguments not specified in ARGS. Otherwise, if
6775 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6776 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6777 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6781 coerce_template_parms (tree parms,
6784 tsubst_flags_t complain,
6785 bool require_all_args,
6786 bool use_default_args)
6788 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6791 tree new_inner_args;
6792 int saved_unevaluated_operand;
6793 int saved_inhibit_evaluation_warnings;
6795 /* When used as a boolean value, indicates whether this is a
6796 variadic template parameter list. Since it's an int, we can also
6797 subtract it from nparms to get the number of non-variadic
6800 int post_variadic_parms = 0;
6802 if (args == error_mark_node)
6803 return error_mark_node;
6805 nparms = TREE_VEC_LENGTH (parms);
6807 /* Determine if there are any parameter packs. */
6808 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6810 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6812 ++post_variadic_parms;
6813 if (template_parameter_pack_p (tparm))
6817 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6818 /* If there are no parameters that follow a parameter pack, we need to
6819 expand any argument packs so that we can deduce a parameter pack from
6820 some non-packed args followed by an argument pack, as in variadic85.C.
6821 If there are such parameters, we need to leave argument packs intact
6822 so the arguments are assigned properly. This can happen when dealing
6823 with a nested class inside a partial specialization of a class
6824 template, as in variadic92.C, or when deducing a template parameter pack
6825 from a sub-declarator, as in variadic114.C. */
6826 if (!post_variadic_parms)
6827 inner_args = expand_template_argument_pack (inner_args);
6829 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6830 if ((nargs > nparms && !variadic_p)
6831 || (nargs < nparms - variadic_p
6833 && !any_pack_expanson_args_p (inner_args)
6834 && (!use_default_args
6835 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6836 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6838 if (complain & tf_error)
6842 nparms -= variadic_p;
6843 error ("wrong number of template arguments "
6844 "(%d, should be %d or more)", nargs, nparms);
6847 error ("wrong number of template arguments "
6848 "(%d, should be %d)", nargs, nparms);
6851 error ("provided for %q+D", in_decl);
6854 return error_mark_node;
6857 /* We need to evaluate the template arguments, even though this
6858 template-id may be nested within a "sizeof". */
6859 saved_unevaluated_operand = cp_unevaluated_operand;
6860 cp_unevaluated_operand = 0;
6861 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6862 c_inhibit_evaluation_warnings = 0;
6863 new_inner_args = make_tree_vec (nparms);
6864 new_args = add_outermost_template_args (args, new_inner_args);
6865 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6870 /* Get the Ith template parameter. */
6871 parm = TREE_VEC_ELT (parms, parm_idx);
6873 if (parm == error_mark_node)
6875 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6879 /* Calculate the next argument. */
6880 if (arg_idx < nargs)
6881 arg = TREE_VEC_ELT (inner_args, arg_idx);
6885 if (template_parameter_pack_p (TREE_VALUE (parm))
6886 && !(arg && ARGUMENT_PACK_P (arg)))
6888 /* All remaining arguments will be placed in the
6889 template parameter pack PARM. */
6890 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6891 inner_args, arg_idx,
6895 /* Store this argument. */
6896 if (arg == error_mark_node)
6898 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6900 /* We are done with all of the arguments. */
6907 if (PACK_EXPANSION_P (arg))
6909 /* We don't know how many args we have yet, just
6910 use the unconverted ones for now. */
6911 new_inner_args = inner_args;
6915 else if (require_all_args)
6917 /* There must be a default arg in this case. */
6918 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6920 /* The position of the first default template argument,
6921 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6923 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6924 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6929 if (arg == error_mark_node)
6931 if (complain & tf_error)
6932 error ("template argument %d is invalid", arg_idx + 1);
6935 /* This only occurs if there was an error in the template
6936 parameter list itself (which we would already have
6937 reported) that we are trying to recover from, e.g., a class
6938 template with a parameter list such as
6939 template<typename..., typename>. */
6942 arg = convert_template_argument (TREE_VALUE (parm),
6943 arg, new_args, complain,
6946 if (arg == error_mark_node)
6948 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6950 cp_unevaluated_operand = saved_unevaluated_operand;
6951 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6954 return error_mark_node;
6956 #ifdef ENABLE_CHECKING
6957 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6958 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6959 TREE_VEC_LENGTH (new_inner_args));
6962 return new_inner_args;
6965 /* Returns 1 if template args OT and NT are equivalent. */
6968 template_args_equal (tree ot, tree nt)
6972 if (nt == NULL_TREE || ot == NULL_TREE)
6975 if (TREE_CODE (nt) == TREE_VEC)
6976 /* For member templates */
6977 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6978 else if (PACK_EXPANSION_P (ot))
6979 return (PACK_EXPANSION_P (nt)
6980 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6981 PACK_EXPANSION_PATTERN (nt))
6982 && template_args_equal (PACK_EXPANSION_EXTRA_ARGS (ot),
6983 PACK_EXPANSION_EXTRA_ARGS (nt)));
6984 else if (ARGUMENT_PACK_P (ot))
6989 if (!ARGUMENT_PACK_P (nt))
6992 opack = ARGUMENT_PACK_ARGS (ot);
6993 npack = ARGUMENT_PACK_ARGS (nt);
6994 len = TREE_VEC_LENGTH (opack);
6995 if (TREE_VEC_LENGTH (npack) != len)
6997 for (i = 0; i < len; ++i)
6998 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6999 TREE_VEC_ELT (npack, i)))
7003 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
7005 /* We get here probably because we are in the middle of substituting
7006 into the pattern of a pack expansion. In that case the
7007 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
7008 interested in. So we want to use the initial pack argument for
7010 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
7011 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
7012 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
7013 return template_args_equal (ot, nt);
7015 else if (TYPE_P (nt))
7016 return TYPE_P (ot) && same_type_p (ot, nt);
7017 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
7020 return cp_tree_equal (ot, nt);
7023 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets of
7024 template arguments. Returns 0 otherwise, and updates OLDARG_PTR and
7025 NEWARG_PTR with the offending arguments if they are non-NULL. */
7028 comp_template_args_with_info (tree oldargs, tree newargs,
7029 tree *oldarg_ptr, tree *newarg_ptr)
7033 if (oldargs == newargs)
7036 if (!oldargs || !newargs)
7039 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
7042 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
7044 tree nt = TREE_VEC_ELT (newargs, i);
7045 tree ot = TREE_VEC_ELT (oldargs, i);
7047 if (! template_args_equal (ot, nt))
7049 if (oldarg_ptr != NULL)
7051 if (newarg_ptr != NULL)
7059 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
7060 of template arguments. Returns 0 otherwise. */
7063 comp_template_args (tree oldargs, tree newargs)
7065 return comp_template_args_with_info (oldargs, newargs, NULL, NULL);
7069 add_pending_template (tree d)
7071 tree ti = (TYPE_P (d)
7072 ? CLASSTYPE_TEMPLATE_INFO (d)
7073 : DECL_TEMPLATE_INFO (d));
7074 struct pending_template *pt;
7077 if (TI_PENDING_TEMPLATE_FLAG (ti))
7080 /* We are called both from instantiate_decl, where we've already had a
7081 tinst_level pushed, and instantiate_template, where we haven't.
7083 level = !current_tinst_level || current_tinst_level->decl != d;
7086 push_tinst_level (d);
7088 pt = ggc_alloc_pending_template ();
7090 pt->tinst = current_tinst_level;
7091 if (last_pending_template)
7092 last_pending_template->next = pt;
7094 pending_templates = pt;
7096 last_pending_template = pt;
7098 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
7105 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
7106 ARGLIST. Valid choices for FNS are given in the cp-tree.def
7107 documentation for TEMPLATE_ID_EXPR. */
7110 lookup_template_function (tree fns, tree arglist)
7114 if (fns == error_mark_node || arglist == error_mark_node)
7115 return error_mark_node;
7117 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
7119 if (!is_overloaded_fn (fns) && TREE_CODE (fns) != IDENTIFIER_NODE)
7121 error ("%q#D is not a function template", fns);
7122 return error_mark_node;
7125 if (BASELINK_P (fns))
7127 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
7129 BASELINK_FUNCTIONS (fns),
7134 type = TREE_TYPE (fns);
7135 if (TREE_CODE (fns) == OVERLOAD || !type)
7136 type = unknown_type_node;
7138 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
7141 /* Within the scope of a template class S<T>, the name S gets bound
7142 (in build_self_reference) to a TYPE_DECL for the class, not a
7143 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
7144 or one of its enclosing classes, and that type is a template,
7145 return the associated TEMPLATE_DECL. Otherwise, the original
7148 Also handle the case when DECL is a TREE_LIST of ambiguous
7149 injected-class-names from different bases. */
7152 maybe_get_template_decl_from_type_decl (tree decl)
7154 if (decl == NULL_TREE)
7157 /* DR 176: A lookup that finds an injected-class-name (10.2
7158 [class.member.lookup]) can result in an ambiguity in certain cases
7159 (for example, if it is found in more than one base class). If all of
7160 the injected-class-names that are found refer to specializations of
7161 the same class template, and if the name is followed by a
7162 template-argument-list, the reference refers to the class template
7163 itself and not a specialization thereof, and is not ambiguous. */
7164 if (TREE_CODE (decl) == TREE_LIST)
7166 tree t, tmpl = NULL_TREE;
7167 for (t = decl; t; t = TREE_CHAIN (t))
7169 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
7172 else if (tmpl != elt)
7175 if (tmpl && t == NULL_TREE)
7181 return (decl != NULL_TREE
7182 && DECL_SELF_REFERENCE_P (decl)
7183 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
7184 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
7187 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
7188 parameters, find the desired type.
7190 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
7192 IN_DECL, if non-NULL, is the template declaration we are trying to
7195 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
7196 the class we are looking up.
7198 Issue error and warning messages under control of COMPLAIN.
7200 If the template class is really a local class in a template
7201 function, then the FUNCTION_CONTEXT is the function in which it is
7204 ??? Note that this function is currently called *twice* for each
7205 template-id: the first time from the parser, while creating the
7206 incomplete type (finish_template_type), and the second type during the
7207 real instantiation (instantiate_template_class). This is surely something
7208 that we want to avoid. It also causes some problems with argument
7209 coercion (see convert_nontype_argument for more information on this). */
7212 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
7213 int entering_scope, tsubst_flags_t complain)
7215 tree templ = NULL_TREE, parmlist;
7222 if (TREE_CODE (d1) == IDENTIFIER_NODE)
7224 tree value = innermost_non_namespace_value (d1);
7225 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
7230 push_decl_namespace (context);
7231 templ = lookup_name (d1);
7232 templ = maybe_get_template_decl_from_type_decl (templ);
7234 pop_decl_namespace ();
7237 context = DECL_CONTEXT (templ);
7239 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
7241 tree type = TREE_TYPE (d1);
7243 /* If we are declaring a constructor, say A<T>::A<T>, we will get
7244 an implicit typename for the second A. Deal with it. */
7245 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
7246 type = TREE_TYPE (type);
7248 if (CLASSTYPE_TEMPLATE_INFO (type))
7250 templ = CLASSTYPE_TI_TEMPLATE (type);
7251 d1 = DECL_NAME (templ);
7254 else if (TREE_CODE (d1) == ENUMERAL_TYPE
7255 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
7257 templ = TYPE_TI_TEMPLATE (d1);
7258 d1 = DECL_NAME (templ);
7260 else if (TREE_CODE (d1) == TEMPLATE_DECL
7261 && DECL_TEMPLATE_RESULT (d1)
7262 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
7265 d1 = DECL_NAME (templ);
7266 context = DECL_CONTEXT (templ);
7269 /* Issue an error message if we didn't find a template. */
7272 if (complain & tf_error)
7273 error ("%qT is not a template", d1);
7274 return error_mark_node;
7277 if (TREE_CODE (templ) != TEMPLATE_DECL
7278 /* Make sure it's a user visible template, if it was named by
7280 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
7281 && !PRIMARY_TEMPLATE_P (templ)))
7283 if (complain & tf_error)
7285 error ("non-template type %qT used as a template", d1);
7287 error ("for template declaration %q+D", in_decl);
7289 return error_mark_node;
7292 complain &= ~tf_user;
7294 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
7296 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
7297 template arguments */
7303 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
7305 /* Consider an example where a template template parameter declared as
7307 template <class T, class U = std::allocator<T> > class TT
7309 The template parameter level of T and U are one level larger than
7310 of TT. To proper process the default argument of U, say when an
7311 instantiation `TT<int>' is seen, we need to build the full
7312 arguments containing {int} as the innermost level. Outer levels,
7313 available when not appearing as default template argument, can be
7314 obtained from the arguments of the enclosing template.
7316 Suppose that TT is later substituted with std::vector. The above
7317 instantiation is `TT<int, std::allocator<T> >' with TT at
7318 level 1, and T at level 2, while the template arguments at level 1
7319 becomes {std::vector} and the inner level 2 is {int}. */
7321 outer = DECL_CONTEXT (templ);
7323 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
7324 else if (current_template_parms)
7325 /* This is an argument of the current template, so we haven't set
7326 DECL_CONTEXT yet. */
7327 outer = current_template_args ();
7330 arglist = add_to_template_args (outer, arglist);
7332 arglist2 = coerce_template_parms (parmlist, arglist, templ,
7334 /*require_all_args=*/true,
7335 /*use_default_args=*/true);
7336 if (arglist2 == error_mark_node
7337 || (!uses_template_parms (arglist2)
7338 && check_instantiated_args (templ, arglist2, complain)))
7339 return error_mark_node;
7341 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
7346 tree template_type = TREE_TYPE (templ);
7349 tree found = NULL_TREE;
7352 int is_dependent_type;
7353 int use_partial_inst_tmpl = false;
7355 if (template_type == error_mark_node)
7356 /* An error occured while building the template TEMPL, and a
7357 diagnostic has most certainly been emitted for that
7358 already. Let's propagate that error. */
7359 return error_mark_node;
7361 gen_tmpl = most_general_template (templ);
7362 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
7363 parm_depth = TMPL_PARMS_DEPTH (parmlist);
7364 arg_depth = TMPL_ARGS_DEPTH (arglist);
7366 if (arg_depth == 1 && parm_depth > 1)
7368 /* We've been given an incomplete set of template arguments.
7371 template <class T> struct S1 {
7372 template <class U> struct S2 {};
7373 template <class U> struct S2<U*> {};
7376 we will be called with an ARGLIST of `U*', but the
7377 TEMPLATE will be `template <class T> template
7378 <class U> struct S1<T>::S2'. We must fill in the missing
7381 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
7383 arg_depth = TMPL_ARGS_DEPTH (arglist);
7386 /* Now we should have enough arguments. */
7387 gcc_assert (parm_depth == arg_depth);
7389 /* From here on, we're only interested in the most general
7392 /* Calculate the BOUND_ARGS. These will be the args that are
7393 actually tsubst'd into the definition to create the
7397 /* We have multiple levels of arguments to coerce, at once. */
7399 int saved_depth = TMPL_ARGS_DEPTH (arglist);
7401 tree bound_args = make_tree_vec (parm_depth);
7403 for (i = saved_depth,
7404 t = DECL_TEMPLATE_PARMS (gen_tmpl);
7405 i > 0 && t != NULL_TREE;
7406 --i, t = TREE_CHAIN (t))
7409 if (i == saved_depth)
7410 a = coerce_template_parms (TREE_VALUE (t),
7413 /*require_all_args=*/true,
7414 /*use_default_args=*/true);
7416 /* Outer levels should have already been coerced. */
7417 a = TMPL_ARGS_LEVEL (arglist, i);
7419 /* Don't process further if one of the levels fails. */
7420 if (a == error_mark_node)
7422 /* Restore the ARGLIST to its full size. */
7423 TREE_VEC_LENGTH (arglist) = saved_depth;
7424 return error_mark_node;
7427 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
7429 /* We temporarily reduce the length of the ARGLIST so
7430 that coerce_template_parms will see only the arguments
7431 corresponding to the template parameters it is
7433 TREE_VEC_LENGTH (arglist)--;
7436 /* Restore the ARGLIST to its full size. */
7437 TREE_VEC_LENGTH (arglist) = saved_depth;
7439 arglist = bound_args;
7443 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
7444 INNERMOST_TEMPLATE_ARGS (arglist),
7447 /*require_all_args=*/true,
7448 /*use_default_args=*/true);
7450 if (arglist == error_mark_node)
7451 /* We were unable to bind the arguments. */
7452 return error_mark_node;
7454 /* In the scope of a template class, explicit references to the
7455 template class refer to the type of the template, not any
7456 instantiation of it. For example, in:
7458 template <class T> class C { void f(C<T>); }
7460 the `C<T>' is just the same as `C'. Outside of the
7461 class, however, such a reference is an instantiation. */
7463 || !PRIMARY_TEMPLATE_P (gen_tmpl)
7464 || currently_open_class (template_type))
7465 /* comp_template_args is expensive, check it last. */
7466 && comp_template_args (TYPE_TI_ARGS (template_type),
7468 return template_type;
7470 /* If we already have this specialization, return it. */
7471 elt.tmpl = gen_tmpl;
7473 hash = hash_specialization (&elt);
7474 entry = (spec_entry *) htab_find_with_hash (type_specializations,
7480 is_dependent_type = uses_template_parms (arglist);
7482 /* If the deduced arguments are invalid, then the binding
7484 if (!is_dependent_type
7485 && check_instantiated_args (gen_tmpl,
7486 INNERMOST_TEMPLATE_ARGS (arglist),
7488 return error_mark_node;
7490 if (!is_dependent_type
7491 && !PRIMARY_TEMPLATE_P (gen_tmpl)
7492 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
7493 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
7495 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
7496 DECL_NAME (gen_tmpl),
7497 /*tag_scope=*/ts_global);
7501 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
7503 if (context == error_mark_node)
7504 return error_mark_node;
7507 context = global_namespace;
7509 /* Create the type. */
7510 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
7512 if (!is_dependent_type)
7514 set_current_access_from_decl (TYPE_NAME (template_type));
7515 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
7516 tsubst (ENUM_UNDERLYING_TYPE (template_type),
7517 arglist, complain, in_decl),
7518 SCOPED_ENUM_P (template_type), NULL);
7522 /* We don't want to call start_enum for this type, since
7523 the values for the enumeration constants may involve
7524 template parameters. And, no one should be interested
7525 in the enumeration constants for such a type. */
7526 t = cxx_make_type (ENUMERAL_TYPE);
7527 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
7529 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
7530 ENUM_FIXED_UNDERLYING_TYPE_P (t)
7531 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type);
7533 else if (DECL_ALIAS_TEMPLATE_P (gen_tmpl))
7535 /* The user referred to a specialization of an alias
7536 template represented by GEN_TMPL.
7538 [temp.alias]/2 says:
7540 When a template-id refers to the specialization of an
7541 alias template, it is equivalent to the associated
7542 type obtained by substitution of its
7543 template-arguments for the template-parameters in the
7544 type-id of the alias template. */
7546 t = tsubst (TREE_TYPE (gen_tmpl), arglist, complain, in_decl);
7547 /* Note that the call above (by indirectly calling
7548 register_specialization in tsubst_decl) registers the
7549 TYPE_DECL representing the specialization of the alias
7550 template. So next time someone substitutes ARGLIST for
7551 the template parms into the alias template (GEN_TMPL),
7552 she'll get that TYPE_DECL back. */
7554 if (t == error_mark_node)
7557 else if (CLASS_TYPE_P (template_type))
7559 t = make_class_type (TREE_CODE (template_type));
7560 CLASSTYPE_DECLARED_CLASS (t)
7561 = CLASSTYPE_DECLARED_CLASS (template_type);
7562 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7563 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7565 /* A local class. Make sure the decl gets registered properly. */
7566 if (context == current_function_decl)
7567 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7569 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7570 /* This instantiation is another name for the primary
7571 template type. Set the TYPE_CANONICAL field
7573 TYPE_CANONICAL (t) = template_type;
7574 else if (any_template_arguments_need_structural_equality_p (arglist))
7575 /* Some of the template arguments require structural
7576 equality testing, so this template class requires
7577 structural equality testing. */
7578 SET_TYPE_STRUCTURAL_EQUALITY (t);
7583 /* If we called start_enum or pushtag above, this information
7584 will already be set up. */
7587 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7589 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7590 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7591 DECL_SOURCE_LOCATION (type_decl)
7592 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7595 type_decl = TYPE_NAME (t);
7597 if (CLASS_TYPE_P (template_type))
7599 TREE_PRIVATE (type_decl)
7600 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
7601 TREE_PROTECTED (type_decl)
7602 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
7603 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7605 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7606 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7610 /* Let's consider the explicit specialization of a member
7611 of a class template specialization that is implicitely instantiated,
7616 template<class U> struct M {}; //#0
7621 struct S<int>::M<char> //#1
7625 [temp.expl.spec]/4 says this is valid.
7627 In this case, when we write:
7630 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7633 When we encounter #1, we want to store the partial instantiation
7634 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7636 For all cases other than this "explicit specialization of member of a
7637 class template", we just want to store the most general template into
7638 the CLASSTYPE_TI_TEMPLATE of M.
7640 This case of "explicit specialization of member of a class template"
7642 1/ the enclosing class is an instantiation of, and therefore not
7643 the same as, the context of the most general template, and
7644 2/ we aren't looking at the partial instantiation itself, i.e.
7645 the innermost arguments are not the same as the innermost parms of
7646 the most general template.
7648 So it's only when 1/ and 2/ happens that we want to use the partial
7649 instantiation of the member template in lieu of its most general
7652 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7653 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7654 /* the enclosing class must be an instantiation... */
7655 && CLASS_TYPE_P (context)
7656 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7658 tree partial_inst_args;
7659 TREE_VEC_LENGTH (arglist)--;
7660 ++processing_template_decl;
7662 tsubst (INNERMOST_TEMPLATE_ARGS
7663 (TYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7664 arglist, complain, NULL_TREE);
7665 --processing_template_decl;
7666 TREE_VEC_LENGTH (arglist)++;
7667 use_partial_inst_tmpl =
7668 /*...and we must not be looking at the partial instantiation
7670 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7674 if (!use_partial_inst_tmpl)
7675 /* This case is easy; there are no member templates involved. */
7679 /* This is a full instantiation of a member template. Find
7680 the partial instantiation of which this is an instance. */
7682 /* Temporarily reduce by one the number of levels in the ARGLIST
7683 so as to avoid comparing the last set of arguments. */
7684 TREE_VEC_LENGTH (arglist)--;
7685 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7686 TREE_VEC_LENGTH (arglist)++;
7687 /* FOUND is either a proper class type, or an alias
7688 template specialization. In the later case, it's a
7689 TYPE_DECL, resulting from the substituting of arguments
7690 for parameters in the TYPE_DECL of the alias template
7691 done earlier. So be careful while getting the template
7693 found = TREE_CODE (found) == TYPE_DECL
7694 ? TYPE_TI_TEMPLATE (TREE_TYPE (found))
7695 : CLASSTYPE_TI_TEMPLATE (found);
7698 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7701 slot = htab_find_slot_with_hash (type_specializations,
7702 &elt, hash, INSERT);
7703 entry = ggc_alloc_spec_entry ();
7707 /* Note this use of the partial instantiation so we can check it
7708 later in maybe_process_partial_specialization. */
7709 DECL_TEMPLATE_INSTANTIATIONS (templ)
7710 = tree_cons (arglist, t,
7711 DECL_TEMPLATE_INSTANTIATIONS (templ));
7713 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type)
7714 /* Now that the type has been registered on the instantiations
7715 list, we set up the enumerators. Because the enumeration
7716 constants may involve the enumeration type itself, we make
7717 sure to register the type first, and then create the
7718 constants. That way, doing tsubst_expr for the enumeration
7719 constants won't result in recursive calls here; we'll find
7720 the instantiation and exit above. */
7721 tsubst_enum (template_type, t, arglist);
7723 if (CLASS_TYPE_P (template_type) && is_dependent_type)
7724 /* If the type makes use of template parameters, the
7725 code that generates debugging information will crash. */
7726 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7728 /* Possibly limit visibility based on template args. */
7729 TREE_PUBLIC (type_decl) = 1;
7730 determine_visibility (type_decl);
7736 /* Wrapper for lookup_template_class_1. */
7739 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
7740 int entering_scope, tsubst_flags_t complain)
7743 timevar_push (TV_TEMPLATE_INST);
7744 ret = lookup_template_class_1 (d1, arglist, in_decl, context,
7745 entering_scope, complain);
7746 timevar_pop (TV_TEMPLATE_INST);
7754 /* True when we should also visit template parameters that occur in
7755 non-deduced contexts. */
7756 bool include_nondeduced_p;
7757 struct pointer_set_t *visited;
7760 /* Called from for_each_template_parm via walk_tree. */
7763 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7766 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7767 tree_fn_t fn = pfd->fn;
7768 void *data = pfd->data;
7771 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7772 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7773 pfd->include_nondeduced_p))
7774 return error_mark_node;
7776 switch (TREE_CODE (t))
7779 if (TYPE_PTRMEMFUNC_P (t))
7785 if (!TYPE_TEMPLATE_INFO (t))
7787 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7788 fn, data, pfd->visited,
7789 pfd->include_nondeduced_p))
7790 return error_mark_node;
7794 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7795 fn, data, pfd->visited,
7796 pfd->include_nondeduced_p)
7797 || for_each_template_parm (TYPE_MAX_VALUE (t),
7798 fn, data, pfd->visited,
7799 pfd->include_nondeduced_p))
7800 return error_mark_node;
7804 /* Since we're not going to walk subtrees, we have to do this
7806 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7807 pfd->visited, pfd->include_nondeduced_p))
7808 return error_mark_node;
7812 /* Check the return type. */
7813 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7814 pfd->include_nondeduced_p))
7815 return error_mark_node;
7817 /* Check the parameter types. Since default arguments are not
7818 instantiated until they are needed, the TYPE_ARG_TYPES may
7819 contain expressions that involve template parameters. But,
7820 no-one should be looking at them yet. And, once they're
7821 instantiated, they don't contain template parameters, so
7822 there's no point in looking at them then, either. */
7826 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7827 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7828 pfd->visited, pfd->include_nondeduced_p))
7829 return error_mark_node;
7831 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7832 want walk_tree walking into them itself. */
7838 case UNDERLYING_TYPE:
7839 if (pfd->include_nondeduced_p
7840 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7842 pfd->include_nondeduced_p))
7843 return error_mark_node;
7848 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7849 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7850 pfd->visited, pfd->include_nondeduced_p))
7851 return error_mark_node;
7856 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7857 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7858 pfd->visited, pfd->include_nondeduced_p))
7859 return error_mark_node;
7860 if (DECL_CONTEXT (t)
7861 && pfd->include_nondeduced_p
7862 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7863 pfd->visited, pfd->include_nondeduced_p))
7864 return error_mark_node;
7867 case BOUND_TEMPLATE_TEMPLATE_PARM:
7868 /* Record template parameters such as `T' inside `TT<T>'. */
7869 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7870 pfd->include_nondeduced_p))
7871 return error_mark_node;
7874 case TEMPLATE_TEMPLATE_PARM:
7875 case TEMPLATE_TYPE_PARM:
7876 case TEMPLATE_PARM_INDEX:
7877 if (fn && (*fn)(t, data))
7878 return error_mark_node;
7880 return error_mark_node;
7884 /* A template template parameter is encountered. */
7885 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7886 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7887 pfd->include_nondeduced_p))
7888 return error_mark_node;
7890 /* Already substituted template template parameter */
7896 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7898 pfd->include_nondeduced_p))
7899 return error_mark_node;
7903 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7904 && pfd->include_nondeduced_p
7905 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7906 (TREE_TYPE (t)), fn, data,
7907 pfd->visited, pfd->include_nondeduced_p))
7908 return error_mark_node;
7913 /* If there's no type, then this thing must be some expression
7914 involving template parameters. */
7915 if (!fn && !TREE_TYPE (t))
7916 return error_mark_node;
7921 case IMPLICIT_CONV_EXPR:
7922 case REINTERPRET_CAST_EXPR:
7923 case CONST_CAST_EXPR:
7924 case STATIC_CAST_EXPR:
7925 case DYNAMIC_CAST_EXPR:
7929 case PSEUDO_DTOR_EXPR:
7931 return error_mark_node;
7938 /* We didn't find any template parameters we liked. */
7942 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7943 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7944 call FN with the parameter and the DATA.
7945 If FN returns nonzero, the iteration is terminated, and
7946 for_each_template_parm returns 1. Otherwise, the iteration
7947 continues. If FN never returns a nonzero value, the value
7948 returned by for_each_template_parm is 0. If FN is NULL, it is
7949 considered to be the function which always returns 1.
7951 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7952 parameters that occur in non-deduced contexts. When false, only
7953 visits those template parameters that can be deduced. */
7956 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7957 struct pointer_set_t *visited,
7958 bool include_nondeduced_p)
7960 struct pair_fn_data pfd;
7966 pfd.include_nondeduced_p = include_nondeduced_p;
7968 /* Walk the tree. (Conceptually, we would like to walk without
7969 duplicates, but for_each_template_parm_r recursively calls
7970 for_each_template_parm, so we would need to reorganize a fair
7971 bit to use walk_tree_without_duplicates, so we keep our own
7974 pfd.visited = visited;
7976 pfd.visited = pointer_set_create ();
7977 result = cp_walk_tree (&t,
7978 for_each_template_parm_r,
7980 pfd.visited) != NULL_TREE;
7985 pointer_set_destroy (pfd.visited);
7992 /* Returns true if T depends on any template parameter. */
7995 uses_template_parms (tree t)
7998 int saved_processing_template_decl;
8000 saved_processing_template_decl = processing_template_decl;
8001 if (!saved_processing_template_decl)
8002 processing_template_decl = 1;
8004 dependent_p = dependent_type_p (t);
8005 else if (TREE_CODE (t) == TREE_VEC)
8006 dependent_p = any_dependent_template_arguments_p (t);
8007 else if (TREE_CODE (t) == TREE_LIST)
8008 dependent_p = (uses_template_parms (TREE_VALUE (t))
8009 || uses_template_parms (TREE_CHAIN (t)));
8010 else if (TREE_CODE (t) == TYPE_DECL)
8011 dependent_p = dependent_type_p (TREE_TYPE (t));
8014 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
8015 || TREE_CODE (t) == OVERLOAD
8017 || TREE_CODE (t) == IDENTIFIER_NODE
8018 || TREE_CODE (t) == TRAIT_EXPR
8019 || TREE_CODE (t) == CONSTRUCTOR
8020 || CONSTANT_CLASS_P (t))
8021 dependent_p = (type_dependent_expression_p (t)
8022 || value_dependent_expression_p (t));
8025 gcc_assert (t == error_mark_node);
8026 dependent_p = false;
8029 processing_template_decl = saved_processing_template_decl;
8034 /* Returns true if T depends on any template parameter with level LEVEL. */
8037 uses_template_parms_level (tree t, int level)
8039 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
8040 /*include_nondeduced_p=*/true);
8043 /* Returns TRUE iff INST is an instantiation we don't need to do in an
8044 ill-formed translation unit, i.e. a variable or function that isn't
8045 usable in a constant expression. */
8048 neglectable_inst_p (tree d)
8051 && !(TREE_CODE (d) == FUNCTION_DECL ? DECL_DECLARED_CONSTEXPR_P (d)
8052 : decl_maybe_constant_var_p (d)));
8055 /* Returns TRUE iff we should refuse to instantiate DECL because it's
8056 neglectable and instantiated from within an erroneous instantiation. */
8059 limit_bad_template_recursion (tree decl)
8061 struct tinst_level *lev = current_tinst_level;
8062 int errs = errorcount + sorrycount;
8063 if (lev == NULL || errs == 0 || !neglectable_inst_p (decl))
8066 for (; lev; lev = lev->next)
8067 if (neglectable_inst_p (lev->decl))
8070 return (lev && errs > lev->errors);
8073 static int tinst_depth;
8074 extern int max_tinst_depth;
8075 #ifdef GATHER_STATISTICS
8078 static GTY(()) struct tinst_level *last_error_tinst_level;
8080 /* We're starting to instantiate D; record the template instantiation context
8081 for diagnostics and to restore it later. */
8084 push_tinst_level (tree d)
8086 struct tinst_level *new_level;
8088 if (tinst_depth >= max_tinst_depth)
8090 last_error_tinst_level = current_tinst_level;
8091 if (TREE_CODE (d) == TREE_LIST)
8092 error ("template instantiation depth exceeds maximum of %d (use "
8093 "-ftemplate-depth= to increase the maximum) substituting %qS",
8094 max_tinst_depth, d);
8096 error ("template instantiation depth exceeds maximum of %d (use "
8097 "-ftemplate-depth= to increase the maximum) instantiating %qD",
8098 max_tinst_depth, d);
8100 print_instantiation_context ();
8105 /* If the current instantiation caused problems, don't let it instantiate
8106 anything else. Do allow deduction substitution and decls usable in
8107 constant expressions. */
8108 if (limit_bad_template_recursion (d))
8111 new_level = ggc_alloc_tinst_level ();
8112 new_level->decl = d;
8113 new_level->locus = input_location;
8114 new_level->errors = errorcount+sorrycount;
8115 new_level->in_system_header_p = in_system_header;
8116 new_level->next = current_tinst_level;
8117 current_tinst_level = new_level;
8120 #ifdef GATHER_STATISTICS
8121 if (tinst_depth > depth_reached)
8122 depth_reached = tinst_depth;
8128 /* We're done instantiating this template; return to the instantiation
8132 pop_tinst_level (void)
8134 /* Restore the filename and line number stashed away when we started
8135 this instantiation. */
8136 input_location = current_tinst_level->locus;
8137 current_tinst_level = current_tinst_level->next;
8141 /* We're instantiating a deferred template; restore the template
8142 instantiation context in which the instantiation was requested, which
8143 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
8146 reopen_tinst_level (struct tinst_level *level)
8148 struct tinst_level *t;
8151 for (t = level; t; t = t->next)
8154 current_tinst_level = level;
8156 if (current_tinst_level)
8157 current_tinst_level->errors = errorcount+sorrycount;
8161 /* Returns the TINST_LEVEL which gives the original instantiation
8164 struct tinst_level *
8165 outermost_tinst_level (void)
8167 struct tinst_level *level = current_tinst_level;
8170 level = level->next;
8174 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
8177 parameter_of_template_p (tree parm, tree templ)
8182 if (!parm || !templ)
8185 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
8186 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8188 parms = DECL_TEMPLATE_PARMS (templ);
8189 parms = INNERMOST_TEMPLATE_PARMS (parms);
8191 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
8193 tree p = TREE_VALUE (TREE_VEC_ELT (parms, i));
8194 if (p == error_mark_node)
8198 || (DECL_INITIAL (parm)
8199 && DECL_INITIAL (parm) == DECL_INITIAL (p)))
8206 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
8207 vector of template arguments, as for tsubst.
8209 Returns an appropriate tsubst'd friend declaration. */
8212 tsubst_friend_function (tree decl, tree args)
8216 if (TREE_CODE (decl) == FUNCTION_DECL
8217 && DECL_TEMPLATE_INSTANTIATION (decl)
8218 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
8219 /* This was a friend declared with an explicit template
8220 argument list, e.g.:
8224 to indicate that f was a template instantiation, not a new
8225 function declaration. Now, we have to figure out what
8226 instantiation of what template. */
8228 tree template_id, arglist, fns;
8231 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
8233 /* Friend functions are looked up in the containing namespace scope.
8234 We must enter that scope, to avoid finding member functions of the
8235 current class with same name. */
8236 push_nested_namespace (ns);
8237 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
8238 tf_warning_or_error, NULL_TREE,
8239 /*integral_constant_expression_p=*/false);
8240 pop_nested_namespace (ns);
8241 arglist = tsubst (DECL_TI_ARGS (decl), args,
8242 tf_warning_or_error, NULL_TREE);
8243 template_id = lookup_template_function (fns, arglist);
8245 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8246 tmpl = determine_specialization (template_id, new_friend,
8248 /*need_member_template=*/0,
8249 TREE_VEC_LENGTH (args),
8251 return instantiate_template (tmpl, new_args, tf_error);
8254 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8256 /* The NEW_FRIEND will look like an instantiation, to the
8257 compiler, but is not an instantiation from the point of view of
8258 the language. For example, we might have had:
8260 template <class T> struct S {
8261 template <class U> friend void f(T, U);
8264 Then, in S<int>, template <class U> void f(int, U) is not an
8265 instantiation of anything. */
8266 if (new_friend == error_mark_node)
8267 return error_mark_node;
8269 DECL_USE_TEMPLATE (new_friend) = 0;
8270 if (TREE_CODE (decl) == TEMPLATE_DECL)
8272 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
8273 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
8274 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
8277 /* The mangled name for the NEW_FRIEND is incorrect. The function
8278 is not a template instantiation and should not be mangled like
8279 one. Therefore, we forget the mangling here; we'll recompute it
8280 later if we need it. */
8281 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
8283 SET_DECL_RTL (new_friend, NULL);
8284 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
8287 if (DECL_NAMESPACE_SCOPE_P (new_friend))
8290 tree new_friend_template_info;
8291 tree new_friend_result_template_info;
8293 int new_friend_is_defn;
8295 /* We must save some information from NEW_FRIEND before calling
8296 duplicate decls since that function will free NEW_FRIEND if
8298 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
8299 new_friend_is_defn =
8300 (DECL_INITIAL (DECL_TEMPLATE_RESULT
8301 (template_for_substitution (new_friend)))
8303 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
8305 /* This declaration is a `primary' template. */
8306 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
8308 new_friend_result_template_info
8309 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
8312 new_friend_result_template_info = NULL_TREE;
8314 /* Make the init_value nonzero so pushdecl knows this is a defn. */
8315 if (new_friend_is_defn)
8316 DECL_INITIAL (new_friend) = error_mark_node;
8318 /* Inside pushdecl_namespace_level, we will push into the
8319 current namespace. However, the friend function should go
8320 into the namespace of the template. */
8321 ns = decl_namespace_context (new_friend);
8322 push_nested_namespace (ns);
8323 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
8324 pop_nested_namespace (ns);
8326 if (old_decl == error_mark_node)
8327 return error_mark_node;
8329 if (old_decl != new_friend)
8331 /* This new friend declaration matched an existing
8332 declaration. For example, given:
8334 template <class T> void f(T);
8335 template <class U> class C {
8336 template <class T> friend void f(T) {}
8339 the friend declaration actually provides the definition
8340 of `f', once C has been instantiated for some type. So,
8341 old_decl will be the out-of-class template declaration,
8342 while new_friend is the in-class definition.
8344 But, if `f' was called before this point, the
8345 instantiation of `f' will have DECL_TI_ARGS corresponding
8346 to `T' but not to `U', references to which might appear
8347 in the definition of `f'. Previously, the most general
8348 template for an instantiation of `f' was the out-of-class
8349 version; now it is the in-class version. Therefore, we
8350 run through all specialization of `f', adding to their
8351 DECL_TI_ARGS appropriately. In particular, they need a
8352 new set of outer arguments, corresponding to the
8353 arguments for this class instantiation.
8355 The same situation can arise with something like this:
8358 template <class T> class C {
8362 when `C<int>' is instantiated. Now, `f(int)' is defined
8365 if (!new_friend_is_defn)
8366 /* On the other hand, if the in-class declaration does
8367 *not* provide a definition, then we don't want to alter
8368 existing definitions. We can just leave everything
8373 tree new_template = TI_TEMPLATE (new_friend_template_info);
8374 tree new_args = TI_ARGS (new_friend_template_info);
8376 /* Overwrite whatever template info was there before, if
8377 any, with the new template information pertaining to
8379 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
8381 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
8383 /* We should have called reregister_specialization in
8385 gcc_assert (retrieve_specialization (new_template,
8389 /* Instantiate it if the global has already been used. */
8390 if (DECL_ODR_USED (old_decl))
8391 instantiate_decl (old_decl, /*defer_ok=*/true,
8392 /*expl_inst_class_mem_p=*/false);
8398 /* Indicate that the old function template is a partial
8400 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
8401 = new_friend_result_template_info;
8403 gcc_assert (new_template
8404 == most_general_template (new_template));
8405 gcc_assert (new_template != old_decl);
8407 /* Reassign any specializations already in the hash table
8408 to the new more general template, and add the
8409 additional template args. */
8410 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
8414 tree spec = TREE_VALUE (t);
8417 elt.tmpl = old_decl;
8418 elt.args = DECL_TI_ARGS (spec);
8419 elt.spec = NULL_TREE;
8421 htab_remove_elt (decl_specializations, &elt);
8424 = add_outermost_template_args (new_args,
8425 DECL_TI_ARGS (spec));
8427 register_specialization
8428 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
8431 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
8435 /* The information from NEW_FRIEND has been merged into OLD_DECL
8436 by duplicate_decls. */
8437 new_friend = old_decl;
8442 tree context = DECL_CONTEXT (new_friend);
8446 template <class T> class C {
8447 template <class U> friend void C1<U>::f (); // case 1
8448 friend void C2<T>::f (); // case 2
8450 we only need to make sure CONTEXT is a complete type for
8451 case 2. To distinguish between the two cases, we note that
8452 CONTEXT of case 1 remains dependent type after tsubst while
8453 this isn't true for case 2. */
8454 ++processing_template_decl;
8455 dependent_p = dependent_type_p (context);
8456 --processing_template_decl;
8459 && !complete_type_or_else (context, NULL_TREE))
8460 return error_mark_node;
8462 if (COMPLETE_TYPE_P (context))
8464 /* Check to see that the declaration is really present, and,
8465 possibly obtain an improved declaration. */
8466 tree fn = check_classfn (context,
8467 new_friend, NULL_TREE);
8477 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
8478 template arguments, as for tsubst.
8480 Returns an appropriate tsubst'd friend type or error_mark_node on
8484 tsubst_friend_class (tree friend_tmpl, tree args)
8490 context = CP_DECL_CONTEXT (friend_tmpl);
8492 if (context != global_namespace)
8494 if (TREE_CODE (context) == NAMESPACE_DECL)
8495 push_nested_namespace (context);
8497 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
8500 /* Look for a class template declaration. We look for hidden names
8501 because two friend declarations of the same template are the
8502 same. For example, in:
8505 template <typename> friend class F;
8507 template <typename> struct B {
8508 template <typename> friend class F;
8511 both F templates are the same. */
8512 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
8513 /*block_p=*/true, 0,
8514 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
8516 /* But, if we don't find one, it might be because we're in a
8517 situation like this:
8525 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
8526 for `S<int>', not the TEMPLATE_DECL. */
8527 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
8529 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
8530 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
8533 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
8535 /* The friend template has already been declared. Just
8536 check to see that the declarations match, and install any new
8537 default parameters. We must tsubst the default parameters,
8538 of course. We only need the innermost template parameters
8539 because that is all that redeclare_class_template will look
8541 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
8542 > TMPL_ARGS_DEPTH (args))
8545 location_t saved_input_location;
8546 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
8547 args, tf_warning_or_error);
8549 saved_input_location = input_location;
8550 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
8551 redeclare_class_template (TREE_TYPE (tmpl), parms);
8552 input_location = saved_input_location;
8556 friend_type = TREE_TYPE (tmpl);
8560 /* The friend template has not already been declared. In this
8561 case, the instantiation of the template class will cause the
8562 injection of this template into the global scope. */
8563 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
8564 if (tmpl == error_mark_node)
8565 return error_mark_node;
8567 /* The new TMPL is not an instantiation of anything, so we
8568 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
8569 the new type because that is supposed to be the corresponding
8570 template decl, i.e., TMPL. */
8571 DECL_USE_TEMPLATE (tmpl) = 0;
8572 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
8573 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
8574 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
8575 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
8577 /* Inject this template into the global scope. */
8578 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
8581 if (context != global_namespace)
8583 if (TREE_CODE (context) == NAMESPACE_DECL)
8584 pop_nested_namespace (context);
8586 pop_nested_class ();
8592 /* Returns zero if TYPE cannot be completed later due to circularity.
8593 Otherwise returns one. */
8596 can_complete_type_without_circularity (tree type)
8598 if (type == NULL_TREE || type == error_mark_node)
8600 else if (COMPLETE_TYPE_P (type))
8602 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
8603 return can_complete_type_without_circularity (TREE_TYPE (type));
8604 else if (CLASS_TYPE_P (type)
8605 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
8611 /* Apply any attributes which had to be deferred until instantiation
8612 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
8613 ARGS, COMPLAIN, IN_DECL are as tsubst. */
8616 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8617 tree args, tsubst_flags_t complain, tree in_decl)
8619 tree last_dep = NULL_TREE;
8623 for (t = attributes; t; t = TREE_CHAIN (t))
8624 if (ATTR_IS_DEPENDENT (t))
8627 attributes = copy_list (attributes);
8631 if (DECL_P (*decl_p))
8633 if (TREE_TYPE (*decl_p) == error_mark_node)
8635 p = &DECL_ATTRIBUTES (*decl_p);
8638 p = &TYPE_ATTRIBUTES (*decl_p);
8642 tree late_attrs = NULL_TREE;
8643 tree *q = &late_attrs;
8645 for (*p = attributes; *p; )
8648 if (ATTR_IS_DEPENDENT (t))
8650 *p = TREE_CHAIN (t);
8651 TREE_CHAIN (t) = NULL_TREE;
8652 /* If the first attribute argument is an identifier, don't
8653 pass it through tsubst. Attributes like mode, format,
8654 cleanup and several target specific attributes expect it
8657 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8658 && TREE_VALUE (TREE_VALUE (t))
8659 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8660 == IDENTIFIER_NODE))
8663 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8665 /*integral_constant_expression_p=*/false);
8666 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8668 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8673 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8674 /*integral_constant_expression_p=*/false);
8676 q = &TREE_CHAIN (t);
8679 p = &TREE_CHAIN (t);
8682 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8686 /* Perform (or defer) access check for typedefs that were referenced
8687 from within the template TMPL code.
8688 This is a subroutine of instantiate_template and instantiate_class_template.
8689 TMPL is the template to consider and TARGS is the list of arguments of
8693 perform_typedefs_access_check (tree tmpl, tree targs)
8695 location_t saved_location;
8697 qualified_typedef_usage_t *iter;
8700 || (!CLASS_TYPE_P (tmpl)
8701 && TREE_CODE (tmpl) != FUNCTION_DECL))
8704 saved_location = input_location;
8705 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
8706 get_types_needing_access_check (tmpl),
8709 tree type_decl = iter->typedef_decl;
8710 tree type_scope = iter->context;
8712 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8715 if (uses_template_parms (type_decl))
8716 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8717 if (uses_template_parms (type_scope))
8718 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8720 /* Make access check error messages point to the location
8721 of the use of the typedef. */
8722 input_location = iter->locus;
8723 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8724 type_decl, type_decl);
8726 input_location = saved_location;
8730 instantiate_class_template_1 (tree type)
8732 tree templ, args, pattern, t, member;
8736 unsigned int saved_maximum_field_alignment;
8738 if (type == error_mark_node)
8739 return error_mark_node;
8741 if (COMPLETE_OR_OPEN_TYPE_P (type)
8742 || uses_template_parms (type))
8745 /* Figure out which template is being instantiated. */
8746 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8747 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8749 /* Determine what specialization of the original template to
8751 t = most_specialized_class (type, templ, tf_warning_or_error);
8752 if (t == error_mark_node)
8754 TYPE_BEING_DEFINED (type) = 1;
8755 return error_mark_node;
8759 /* This TYPE is actually an instantiation of a partial
8760 specialization. We replace the innermost set of ARGS with
8761 the arguments appropriate for substitution. For example,
8764 template <class T> struct S {};
8765 template <class T> struct S<T*> {};
8767 and supposing that we are instantiating S<int*>, ARGS will
8768 presently be {int*} -- but we need {int}. */
8769 pattern = TREE_TYPE (t);
8770 args = TREE_PURPOSE (t);
8774 pattern = TREE_TYPE (templ);
8775 args = CLASSTYPE_TI_ARGS (type);
8778 /* If the template we're instantiating is incomplete, then clearly
8779 there's nothing we can do. */
8780 if (!COMPLETE_TYPE_P (pattern))
8783 /* If we've recursively instantiated too many templates, stop. */
8784 if (! push_tinst_level (type))
8787 /* Now we're really doing the instantiation. Mark the type as in
8788 the process of being defined. */
8789 TYPE_BEING_DEFINED (type) = 1;
8791 /* We may be in the middle of deferred access check. Disable
8793 push_deferring_access_checks (dk_no_deferred);
8795 push_to_top_level ();
8796 /* Use #pragma pack from the template context. */
8797 saved_maximum_field_alignment = maximum_field_alignment;
8798 maximum_field_alignment = TYPE_PRECISION (pattern);
8800 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8802 /* Set the input location to the most specialized template definition.
8803 This is needed if tsubsting causes an error. */
8804 typedecl = TYPE_MAIN_DECL (pattern);
8805 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8806 DECL_SOURCE_LOCATION (typedecl);
8808 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8809 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8810 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8811 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8812 if (ANON_AGGR_TYPE_P (pattern))
8813 SET_ANON_AGGR_TYPE_P (type);
8814 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8816 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8817 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8818 /* Adjust visibility for template arguments. */
8819 determine_visibility (TYPE_MAIN_DECL (type));
8821 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8823 pbinfo = TYPE_BINFO (pattern);
8825 /* We should never instantiate a nested class before its enclosing
8826 class; we need to look up the nested class by name before we can
8827 instantiate it, and that lookup should instantiate the enclosing
8829 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8830 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8832 base_list = NULL_TREE;
8833 if (BINFO_N_BASE_BINFOS (pbinfo))
8839 /* We must enter the scope containing the type, as that is where
8840 the accessibility of types named in dependent bases are
8842 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8844 /* Substitute into each of the bases to determine the actual
8846 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8849 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8850 tree expanded_bases = NULL_TREE;
8853 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8856 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8857 args, tf_error, NULL_TREE);
8858 if (expanded_bases == error_mark_node)
8861 len = TREE_VEC_LENGTH (expanded_bases);
8864 for (idx = 0; idx < len; idx++)
8867 /* Extract the already-expanded base class. */
8868 base = TREE_VEC_ELT (expanded_bases, idx);
8870 /* Substitute to figure out the base class. */
8871 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8874 if (base == error_mark_node)
8877 base_list = tree_cons (access, base, base_list);
8878 if (BINFO_VIRTUAL_P (pbase_binfo))
8879 TREE_TYPE (base_list) = integer_type_node;
8883 /* The list is now in reverse order; correct that. */
8884 base_list = nreverse (base_list);
8887 pop_scope (pushed_scope);
8889 /* Now call xref_basetypes to set up all the base-class
8891 xref_basetypes (type, base_list);
8893 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8894 (int) ATTR_FLAG_TYPE_IN_PLACE,
8895 args, tf_error, NULL_TREE);
8896 fixup_attribute_variants (type);
8898 /* Now that our base classes are set up, enter the scope of the
8899 class, so that name lookups into base classes, etc. will work
8900 correctly. This is precisely analogous to what we do in
8901 begin_class_definition when defining an ordinary non-template
8902 class, except we also need to push the enclosing classes. */
8903 push_nested_class (type);
8905 /* Now members are processed in the order of declaration. */
8906 for (member = CLASSTYPE_DECL_LIST (pattern);
8907 member; member = TREE_CHAIN (member))
8909 tree t = TREE_VALUE (member);
8911 if (TREE_PURPOSE (member))
8915 /* Build new CLASSTYPE_NESTED_UTDS. */
8918 bool class_template_p;
8920 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8921 && TYPE_LANG_SPECIFIC (t)
8922 && CLASSTYPE_IS_TEMPLATE (t));
8923 /* If the member is a class template, then -- even after
8924 substitution -- there may be dependent types in the
8925 template argument list for the class. We increment
8926 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8927 that function will assume that no types are dependent
8928 when outside of a template. */
8929 if (class_template_p)
8930 ++processing_template_decl;
8931 newtag = tsubst (t, args, tf_error, NULL_TREE);
8932 if (class_template_p)
8933 --processing_template_decl;
8934 if (newtag == error_mark_node)
8937 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8939 tree name = TYPE_IDENTIFIER (t);
8941 if (class_template_p)
8942 /* Unfortunately, lookup_template_class sets
8943 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8944 instantiation (i.e., for the type of a member
8945 template class nested within a template class.)
8946 This behavior is required for
8947 maybe_process_partial_specialization to work
8948 correctly, but is not accurate in this case;
8949 the TAG is not an instantiation of anything.
8950 (The corresponding TEMPLATE_DECL is an
8951 instantiation, but the TYPE is not.) */
8952 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8954 /* Now, we call pushtag to put this NEWTAG into the scope of
8955 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8956 pushtag calling push_template_decl. We don't have to do
8957 this for enums because it will already have been done in
8960 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8961 pushtag (name, newtag, /*tag_scope=*/ts_current);
8964 else if (TREE_CODE (t) == FUNCTION_DECL
8965 || DECL_FUNCTION_TEMPLATE_P (t))
8967 /* Build new TYPE_METHODS. */
8970 if (TREE_CODE (t) == TEMPLATE_DECL)
8971 ++processing_template_decl;
8972 r = tsubst (t, args, tf_error, NULL_TREE);
8973 if (TREE_CODE (t) == TEMPLATE_DECL)
8974 --processing_template_decl;
8975 set_current_access_from_decl (r);
8976 finish_member_declaration (r);
8977 /* Instantiate members marked with attribute used. */
8978 if (r != error_mark_node && DECL_PRESERVE_P (r))
8983 /* Build new TYPE_FIELDS. */
8984 if (TREE_CODE (t) == STATIC_ASSERT)
8987 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8988 tf_warning_or_error, NULL_TREE,
8989 /*integral_constant_expression_p=*/true);
8990 finish_static_assert (condition,
8991 STATIC_ASSERT_MESSAGE (t),
8992 STATIC_ASSERT_SOURCE_LOCATION (t),
8995 else if (TREE_CODE (t) != CONST_DECL)
8999 /* The file and line for this declaration, to
9000 assist in error message reporting. Since we
9001 called push_tinst_level above, we don't need to
9003 input_location = DECL_SOURCE_LOCATION (t);
9005 if (TREE_CODE (t) == TEMPLATE_DECL)
9006 ++processing_template_decl;
9007 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
9008 if (TREE_CODE (t) == TEMPLATE_DECL)
9009 --processing_template_decl;
9010 if (TREE_CODE (r) == VAR_DECL)
9014 [t]he initialization (and any associated
9015 side-effects) of a static data member does
9016 not occur unless the static data member is
9017 itself used in a way that requires the
9018 definition of the static data member to
9021 Therefore, we do not substitute into the
9022 initialized for the static data member here. */
9023 finish_static_data_member_decl
9026 /*init_const_expr_p=*/false,
9027 /*asmspec_tree=*/NULL_TREE,
9029 /* Instantiate members marked with attribute used. */
9030 if (r != error_mark_node && DECL_PRESERVE_P (r))
9033 else if (TREE_CODE (r) == FIELD_DECL)
9035 /* Determine whether R has a valid type and can be
9036 completed later. If R is invalid, then it is
9037 replaced by error_mark_node so that it will not be
9038 added to TYPE_FIELDS. */
9039 tree rtype = TREE_TYPE (r);
9040 if (can_complete_type_without_circularity (rtype))
9041 complete_type (rtype);
9043 if (!COMPLETE_TYPE_P (rtype))
9045 cxx_incomplete_type_error (r, rtype);
9046 r = error_mark_node;
9050 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
9051 such a thing will already have been added to the field
9052 list by tsubst_enum in finish_member_declaration in the
9053 CLASSTYPE_NESTED_UTDS case above. */
9054 if (!(TREE_CODE (r) == TYPE_DECL
9055 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
9056 && DECL_ARTIFICIAL (r)))
9058 set_current_access_from_decl (r);
9059 finish_member_declaration (r);
9066 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
9068 /* Build new CLASSTYPE_FRIEND_CLASSES. */
9070 tree friend_type = t;
9071 bool adjust_processing_template_decl = false;
9073 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
9075 /* template <class T> friend class C; */
9076 friend_type = tsubst_friend_class (friend_type, args);
9077 adjust_processing_template_decl = true;
9079 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
9081 /* template <class T> friend class C::D; */
9082 friend_type = tsubst (friend_type, args,
9083 tf_warning_or_error, NULL_TREE);
9084 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
9085 friend_type = TREE_TYPE (friend_type);
9086 adjust_processing_template_decl = true;
9088 else if (TREE_CODE (friend_type) == TYPENAME_TYPE
9089 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
9091 /* This could be either
9095 when dependent_type_p is false or
9097 template <class U> friend class T::C;
9100 friend_type = tsubst (friend_type, args,
9101 tf_warning_or_error, NULL_TREE);
9102 /* Bump processing_template_decl for correct
9103 dependent_type_p calculation. */
9104 ++processing_template_decl;
9105 if (dependent_type_p (friend_type))
9106 adjust_processing_template_decl = true;
9107 --processing_template_decl;
9109 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
9110 && hidden_name_p (TYPE_NAME (friend_type)))
9114 where C hasn't been declared yet. Let's lookup name
9115 from namespace scope directly, bypassing any name that
9116 come from dependent base class. */
9117 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
9119 /* The call to xref_tag_from_type does injection for friend
9121 push_nested_namespace (ns);
9123 xref_tag_from_type (friend_type, NULL_TREE,
9124 /*tag_scope=*/ts_current);
9125 pop_nested_namespace (ns);
9127 else if (uses_template_parms (friend_type))
9128 /* friend class C<T>; */
9129 friend_type = tsubst (friend_type, args,
9130 tf_warning_or_error, NULL_TREE);
9135 where C is already declared or
9137 friend class C<int>;
9139 We don't have to do anything in these cases. */
9141 if (adjust_processing_template_decl)
9142 /* Trick make_friend_class into realizing that the friend
9143 we're adding is a template, not an ordinary class. It's
9144 important that we use make_friend_class since it will
9145 perform some error-checking and output cross-reference
9147 ++processing_template_decl;
9149 if (friend_type != error_mark_node)
9150 make_friend_class (type, friend_type, /*complain=*/false);
9152 if (adjust_processing_template_decl)
9153 --processing_template_decl;
9157 /* Build new DECL_FRIENDLIST. */
9160 /* The file and line for this declaration, to
9161 assist in error message reporting. Since we
9162 called push_tinst_level above, we don't need to
9164 input_location = DECL_SOURCE_LOCATION (t);
9166 if (TREE_CODE (t) == TEMPLATE_DECL)
9168 ++processing_template_decl;
9169 push_deferring_access_checks (dk_no_check);
9172 r = tsubst_friend_function (t, args);
9173 add_friend (type, r, /*complain=*/false);
9174 if (TREE_CODE (t) == TEMPLATE_DECL)
9176 pop_deferring_access_checks ();
9177 --processing_template_decl;
9183 if (CLASSTYPE_LAMBDA_EXPR (type))
9185 tree decl = lambda_function (type);
9188 tree lambda = CLASSTYPE_LAMBDA_EXPR (type);
9189 if (LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (lambda))
9191 apply_lambda_return_type (lambda, void_type_node);
9192 LAMBDA_EXPR_RETURN_TYPE (lambda) = NULL_TREE;
9194 instantiate_decl (decl, false, false);
9195 maybe_add_lambda_conv_op (type);
9198 gcc_assert (errorcount);
9201 /* Set the file and line number information to whatever is given for
9202 the class itself. This puts error messages involving generated
9203 implicit functions at a predictable point, and the same point
9204 that would be used for non-template classes. */
9205 input_location = DECL_SOURCE_LOCATION (typedecl);
9207 unreverse_member_declarations (type);
9208 finish_struct_1 (type);
9209 TYPE_BEING_DEFINED (type) = 0;
9211 /* We don't instantiate default arguments for member functions. 14.7.1:
9213 The implicit instantiation of a class template specialization causes
9214 the implicit instantiation of the declarations, but not of the
9215 definitions or default arguments, of the class member functions,
9216 member classes, static data members and member templates.... */
9218 /* Some typedefs referenced from within the template code need to be access
9219 checked at template instantiation time, i.e now. These types were
9220 added to the template at parsing time. Let's get those and perform
9221 the access checks then. */
9222 perform_typedefs_access_check (pattern, args);
9223 perform_deferred_access_checks ();
9224 pop_nested_class ();
9225 maximum_field_alignment = saved_maximum_field_alignment;
9226 pop_from_top_level ();
9227 pop_deferring_access_checks ();
9230 /* The vtable for a template class can be emitted in any translation
9231 unit in which the class is instantiated. When there is no key
9232 method, however, finish_struct_1 will already have added TYPE to
9233 the keyed_classes list. */
9234 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
9235 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
9240 /* Wrapper for instantiate_class_template_1. */
9243 instantiate_class_template (tree type)
9246 timevar_push (TV_TEMPLATE_INST);
9247 ret = instantiate_class_template_1 (type);
9248 timevar_pop (TV_TEMPLATE_INST);
9253 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9259 else if (TYPE_P (t))
9260 r = tsubst (t, args, complain, in_decl);
9263 if (!(complain & tf_warning))
9264 ++c_inhibit_evaluation_warnings;
9265 r = tsubst_expr (t, args, complain, in_decl,
9266 /*integral_constant_expression_p=*/true);
9267 if (!(complain & tf_warning))
9268 --c_inhibit_evaluation_warnings;
9269 /* Preserve the raw-reference nature of T. */
9270 if (TREE_TYPE (t) && TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE
9271 && REFERENCE_REF_P (r))
9272 r = TREE_OPERAND (r, 0);
9277 /* Given a function parameter pack TMPL_PARM and some function parameters
9278 instantiated from it at *SPEC_P, return a NONTYPE_ARGUMENT_PACK of them
9279 and set *SPEC_P to point at the next point in the list. */
9282 extract_fnparm_pack (tree tmpl_parm, tree *spec_p)
9284 /* Collect all of the extra "packed" parameters into an
9288 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
9289 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
9290 tree spec_parm = *spec_p;
9293 for (len = 0; spec_parm; ++len, spec_parm = TREE_CHAIN (spec_parm))
9295 && !function_parameter_expanded_from_pack_p (spec_parm, tmpl_parm))
9298 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
9299 parmvec = make_tree_vec (len);
9300 parmtypevec = make_tree_vec (len);
9301 spec_parm = *spec_p;
9302 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
9304 TREE_VEC_ELT (parmvec, i) = spec_parm;
9305 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
9308 /* Build the argument packs. */
9309 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
9310 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
9311 TREE_TYPE (argpack) = argtypepack;
9312 *spec_p = spec_parm;
9317 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
9318 NONTYPE_ARGUMENT_PACK. */
9321 make_fnparm_pack (tree spec_parm)
9323 return extract_fnparm_pack (NULL_TREE, &spec_parm);
9326 /* Substitute ARGS into T, which is an pack expansion
9327 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
9328 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
9329 (if only a partial substitution could be performed) or
9330 ERROR_MARK_NODE if there was an error. */
9332 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
9336 tree pack, packs = NULL_TREE;
9337 bool unsubstituted_packs = false;
9338 bool real_packs = false;
9339 int missing_level = 0;
9342 htab_t saved_local_specializations = NULL;
9343 bool need_local_specializations = false;
9346 gcc_assert (PACK_EXPANSION_P (t));
9347 pattern = PACK_EXPANSION_PATTERN (t);
9349 /* Add in any args remembered from an earlier partial instantiation. */
9350 args = add_to_template_args (PACK_EXPANSION_EXTRA_ARGS (t), args);
9352 levels = TMPL_ARGS_DEPTH (args);
9354 /* Determine the argument packs that will instantiate the parameter
9355 packs used in the expansion expression. While we're at it,
9356 compute the number of arguments to be expanded and make sure it
9358 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
9359 pack = TREE_CHAIN (pack))
9361 tree parm_pack = TREE_VALUE (pack);
9362 tree arg_pack = NULL_TREE;
9363 tree orig_arg = NULL_TREE;
9366 if (TREE_CODE (parm_pack) == BASES)
9368 if (BASES_DIRECT (parm_pack))
9369 return calculate_direct_bases (tsubst_expr (BASES_TYPE (parm_pack),
9370 args, complain, in_decl, false));
9372 return calculate_bases (tsubst_expr (BASES_TYPE (parm_pack),
9373 args, complain, in_decl, false));
9375 if (TREE_CODE (parm_pack) == PARM_DECL)
9377 if (PACK_EXPANSION_LOCAL_P (t))
9378 arg_pack = retrieve_local_specialization (parm_pack);
9381 /* We can't rely on local_specializations for a parameter
9382 name used later in a function declaration (such as in a
9383 late-specified return type). Even if it exists, it might
9384 have the wrong value for a recursive call. Just make a
9385 dummy decl, since it's only used for its type. */
9386 arg_pack = tsubst_decl (parm_pack, args, complain);
9387 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
9388 /* Partial instantiation of the parm_pack, we can't build
9389 up an argument pack yet. */
9390 arg_pack = NULL_TREE;
9392 arg_pack = make_fnparm_pack (arg_pack);
9393 need_local_specializations = true;
9399 template_parm_level_and_index (parm_pack, &level, &idx);
9401 if (level <= levels)
9402 arg_pack = TMPL_ARG (args, level, idx);
9405 orig_arg = arg_pack;
9406 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
9407 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
9409 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
9410 /* This can only happen if we forget to expand an argument
9411 pack somewhere else. Just return an error, silently. */
9413 result = make_tree_vec (1);
9414 TREE_VEC_ELT (result, 0) = error_mark_node;
9418 if (arg_from_parm_pack_p (arg_pack, parm_pack))
9419 /* The argument pack that the parameter maps to is just an
9420 expansion of the parameter itself, such as one would find
9421 in the implicit typedef of a class inside the class itself.
9422 Consider this parameter "unsubstituted", so that we will
9423 maintain the outer pack expansion. */
9424 arg_pack = NULL_TREE;
9429 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
9431 /* Don't bother trying to do a partial substitution with
9432 incomplete packs; we'll try again after deduction. */
9433 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
9438 else if (len != my_len)
9440 if (!(complain & tf_error))
9441 /* Fail quietly. */;
9442 else if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
9443 error ("mismatched argument pack lengths while expanding "
9447 error ("mismatched argument pack lengths while expanding "
9450 return error_mark_node;
9453 if (TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
9454 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack),
9456 /* This isn't a real argument pack yet. */;
9460 /* Keep track of the parameter packs and their corresponding
9462 packs = tree_cons (parm_pack, arg_pack, packs);
9463 TREE_TYPE (packs) = orig_arg;
9467 /* We can't substitute for this parameter pack. We use a flag as
9468 well as the missing_level counter because function parameter
9469 packs don't have a level. */
9470 unsubstituted_packs = true;
9471 if (!missing_level || missing_level > level)
9472 missing_level = level;
9476 /* We cannot expand this expansion expression, because we don't have
9477 all of the argument packs we need. */
9478 if (unsubstituted_packs)
9482 /* We got some full packs, but we can't substitute them in until we
9483 have values for all the packs. So remember these until then. */
9486 t = make_pack_expansion (pattern);
9488 /* The call to add_to_template_args above assumes no overlap
9489 between saved args and new args, so prune away any fake
9490 args, i.e. those that satisfied arg_from_parm_pack_p above. */
9491 if (missing_level && levels >= missing_level)
9493 gcc_assert (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args)
9494 && missing_level > 1);
9495 TREE_VEC_LENGTH (args) = missing_level - 1;
9496 save_args = copy_node (args);
9497 TREE_VEC_LENGTH (args) = levels;
9502 PACK_EXPANSION_EXTRA_ARGS (t) = save_args;
9506 /* There were no real arguments, we're just replacing a parameter
9507 pack with another version of itself. Substitute into the
9508 pattern and return a PACK_EXPANSION_*. The caller will need to
9510 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9511 t = tsubst_expr (pattern, args, complain, in_decl,
9512 /*integral_constant_expression_p=*/false);
9514 t = tsubst (pattern, args, complain, in_decl);
9515 t = make_pack_expansion (t);
9520 /* We could not find any argument packs that work. */
9522 return error_mark_node;
9524 if (need_local_specializations)
9526 /* We're in a late-specified return type, so create our own local
9527 specializations table; the current table is either NULL or (in the
9528 case of recursive unification) might have bindings that we don't
9529 want to use or alter. */
9530 saved_local_specializations = local_specializations;
9531 local_specializations = htab_create (37,
9532 hash_local_specialization,
9533 eq_local_specializations,
9537 /* For each argument in each argument pack, substitute into the
9539 result = make_tree_vec (len);
9540 for (i = 0; i < len; ++i)
9542 /* For parameter pack, change the substitution of the parameter
9543 pack to the ith argument in its argument pack, then expand
9545 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9547 tree parm = TREE_PURPOSE (pack);
9550 /* Select the Ith argument from the pack. */
9551 if (TREE_CODE (parm) == PARM_DECL)
9555 arg = make_node (ARGUMENT_PACK_SELECT);
9556 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9558 register_local_specialization (arg, parm);
9561 arg = retrieve_local_specialization (parm);
9566 template_parm_level_and_index (parm, &level, &idx);
9570 arg = make_node (ARGUMENT_PACK_SELECT);
9571 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
9572 /* Update the corresponding argument. */
9573 TMPL_ARG (args, level, idx) = arg;
9576 /* Re-use the ARGUMENT_PACK_SELECT. */
9577 arg = TMPL_ARG (args, level, idx);
9579 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
9582 /* Substitute into the PATTERN with the altered arguments. */
9583 if (!TYPE_P (pattern))
9584 TREE_VEC_ELT (result, i) =
9585 tsubst_expr (pattern, args, complain, in_decl,
9586 /*integral_constant_expression_p=*/false);
9588 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
9590 if (TREE_VEC_ELT (result, i) == error_mark_node)
9592 result = error_mark_node;
9597 /* Update ARGS to restore the substitution from parameter packs to
9598 their argument packs. */
9599 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9601 tree parm = TREE_PURPOSE (pack);
9603 if (TREE_CODE (parm) == PARM_DECL)
9604 register_local_specialization (TREE_TYPE (pack), parm);
9608 template_parm_level_and_index (parm, &level, &idx);
9610 /* Update the corresponding argument. */
9611 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
9612 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
9615 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
9619 if (need_local_specializations)
9621 htab_delete (local_specializations);
9622 local_specializations = saved_local_specializations;
9628 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
9629 TMPL. We do this using DECL_PARM_INDEX, which should work even with
9630 parameter packs; all parms generated from a function parameter pack will
9631 have the same DECL_PARM_INDEX. */
9634 get_pattern_parm (tree parm, tree tmpl)
9636 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
9639 if (DECL_ARTIFICIAL (parm))
9641 for (patparm = DECL_ARGUMENTS (pattern);
9642 patparm; patparm = DECL_CHAIN (patparm))
9643 if (DECL_ARTIFICIAL (patparm)
9644 && DECL_NAME (parm) == DECL_NAME (patparm))
9649 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
9650 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
9651 gcc_assert (DECL_PARM_INDEX (patparm)
9652 == DECL_PARM_INDEX (parm));
9658 /* Substitute ARGS into the vector or list of template arguments T. */
9661 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9664 int len, need_new = 0, i, expanded_len_adjust = 0, out;
9667 if (t == error_mark_node)
9668 return error_mark_node;
9670 len = TREE_VEC_LENGTH (t);
9671 elts = XALLOCAVEC (tree, len);
9673 for (i = 0; i < len; i++)
9675 tree orig_arg = TREE_VEC_ELT (t, i);
9678 if (TREE_CODE (orig_arg) == TREE_VEC)
9679 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9680 else if (PACK_EXPANSION_P (orig_arg))
9682 /* Substitute into an expansion expression. */
9683 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9685 if (TREE_CODE (new_arg) == TREE_VEC)
9686 /* Add to the expanded length adjustment the number of
9687 expanded arguments. We subtract one from this
9688 measurement, because the argument pack expression
9689 itself is already counted as 1 in
9690 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9691 the argument pack is empty. */
9692 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9694 else if (ARGUMENT_PACK_P (orig_arg))
9696 /* Substitute into each of the arguments. */
9697 new_arg = TYPE_P (orig_arg)
9698 ? cxx_make_type (TREE_CODE (orig_arg))
9699 : make_node (TREE_CODE (orig_arg));
9701 SET_ARGUMENT_PACK_ARGS (
9703 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9704 args, complain, in_decl));
9706 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9707 new_arg = error_mark_node;
9709 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9710 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9712 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9714 if (TREE_TYPE (new_arg) == error_mark_node)
9715 new_arg = error_mark_node;
9719 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9721 if (new_arg == error_mark_node)
9722 return error_mark_node;
9725 if (new_arg != orig_arg)
9732 /* Make space for the expanded arguments coming from template
9734 t = make_tree_vec (len + expanded_len_adjust);
9735 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9736 arguments for a member template.
9737 In that case each TREE_VEC in ORIG_T represents a level of template
9738 arguments, and ORIG_T won't carry any non defaulted argument count.
9739 It will rather be the nested TREE_VECs that will carry one.
9740 In other words, ORIG_T carries a non defaulted argument count only
9741 if it doesn't contain any nested TREE_VEC. */
9742 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9744 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9745 count += expanded_len_adjust;
9746 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9748 for (i = 0, out = 0; i < len; i++)
9750 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9751 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9752 && TREE_CODE (elts[i]) == TREE_VEC)
9756 /* Now expand the template argument pack "in place". */
9757 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9758 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9762 TREE_VEC_ELT (t, out) = elts[i];
9770 /* Return the result of substituting ARGS into the template parameters
9771 given by PARMS. If there are m levels of ARGS and m + n levels of
9772 PARMS, then the result will contain n levels of PARMS. For
9773 example, if PARMS is `template <class T> template <class U>
9774 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9775 result will be `template <int*, double, class V>'. */
9778 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9783 /* When substituting into a template, we must set
9784 PROCESSING_TEMPLATE_DECL as the template parameters may be
9785 dependent if they are based on one-another, and the dependency
9786 predicates are short-circuit outside of templates. */
9787 ++processing_template_decl;
9789 for (new_parms = &r;
9790 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9791 new_parms = &(TREE_CHAIN (*new_parms)),
9792 parms = TREE_CHAIN (parms))
9795 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9798 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9802 if (parms == error_mark_node)
9805 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9807 if (tuple == error_mark_node)
9810 TREE_VEC_ELT (new_vec, i) =
9811 tsubst_template_parm (tuple, args, complain);
9815 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9816 - TMPL_ARGS_DEPTH (args)),
9817 new_vec, NULL_TREE);
9820 --processing_template_decl;
9825 /* Return the result of substituting ARGS into one template parameter
9826 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9827 parameter and which TREE_PURPOSE is the default argument of the
9828 template parameter. */
9831 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9833 tree default_value, parm_decl;
9835 if (args == NULL_TREE
9837 || t == error_mark_node)
9840 gcc_assert (TREE_CODE (t) == TREE_LIST);
9842 default_value = TREE_PURPOSE (t);
9843 parm_decl = TREE_VALUE (t);
9845 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9846 if (TREE_CODE (parm_decl) == PARM_DECL
9847 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9848 parm_decl = error_mark_node;
9849 default_value = tsubst_template_arg (default_value, args,
9850 complain, NULL_TREE);
9852 return build_tree_list (default_value, parm_decl);
9855 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9856 type T. If T is not an aggregate or enumeration type, it is
9857 handled as if by tsubst. IN_DECL is as for tsubst. If
9858 ENTERING_SCOPE is nonzero, T is the context for a template which
9859 we are presently tsubst'ing. Return the substituted value. */
9862 tsubst_aggr_type (tree t,
9864 tsubst_flags_t complain,
9871 switch (TREE_CODE (t))
9874 if (TYPE_PTRMEMFUNC_P (t))
9875 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9877 /* Else fall through. */
9880 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9885 int saved_unevaluated_operand;
9886 int saved_inhibit_evaluation_warnings;
9888 /* In "sizeof(X<I>)" we need to evaluate "I". */
9889 saved_unevaluated_operand = cp_unevaluated_operand;
9890 cp_unevaluated_operand = 0;
9891 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9892 c_inhibit_evaluation_warnings = 0;
9894 /* First, determine the context for the type we are looking
9896 context = TYPE_CONTEXT (t);
9897 if (context && TYPE_P (context))
9899 context = tsubst_aggr_type (context, args, complain,
9900 in_decl, /*entering_scope=*/1);
9901 /* If context is a nested class inside a class template,
9902 it may still need to be instantiated (c++/33959). */
9903 context = complete_type (context);
9906 /* Then, figure out what arguments are appropriate for the
9907 type we are trying to find. For example, given:
9909 template <class T> struct S;
9910 template <class T, class U> void f(T, U) { S<U> su; }
9912 and supposing that we are instantiating f<int, double>,
9913 then our ARGS will be {int, double}, but, when looking up
9914 S we only want {double}. */
9915 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9917 if (argvec == error_mark_node)
9918 r = error_mark_node;
9921 r = lookup_template_class (t, argvec, in_decl, context,
9922 entering_scope, complain);
9923 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9926 cp_unevaluated_operand = saved_unevaluated_operand;
9927 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9932 /* This is not a template type, so there's nothing to do. */
9936 return tsubst (t, args, complain, in_decl);
9940 /* Substitute into the default argument ARG (a default argument for
9941 FN), which has the indicated TYPE. */
9944 tsubst_default_argument (tree fn, tree type, tree arg)
9946 tree saved_class_ptr = NULL_TREE;
9947 tree saved_class_ref = NULL_TREE;
9949 /* This can happen in invalid code. */
9950 if (TREE_CODE (arg) == DEFAULT_ARG)
9953 /* This default argument came from a template. Instantiate the
9954 default argument here, not in tsubst. In the case of
9963 we must be careful to do name lookup in the scope of S<T>,
9964 rather than in the current class. */
9965 push_access_scope (fn);
9966 /* The "this" pointer is not valid in a default argument. */
9969 saved_class_ptr = current_class_ptr;
9970 cp_function_chain->x_current_class_ptr = NULL_TREE;
9971 saved_class_ref = current_class_ref;
9972 cp_function_chain->x_current_class_ref = NULL_TREE;
9975 push_deferring_access_checks(dk_no_deferred);
9976 /* The default argument expression may cause implicitly defined
9977 member functions to be synthesized, which will result in garbage
9978 collection. We must treat this situation as if we were within
9979 the body of function so as to avoid collecting live data on the
9982 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9983 tf_warning_or_error, NULL_TREE,
9984 /*integral_constant_expression_p=*/false);
9986 pop_deferring_access_checks();
9988 /* Restore the "this" pointer. */
9991 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9992 cp_function_chain->x_current_class_ref = saved_class_ref;
9995 /* Make sure the default argument is reasonable. */
9996 arg = check_default_argument (type, arg);
9998 pop_access_scope (fn);
10003 /* Substitute into all the default arguments for FN. */
10006 tsubst_default_arguments (tree fn)
10011 tmpl_args = DECL_TI_ARGS (fn);
10013 /* If this function is not yet instantiated, we certainly don't need
10014 its default arguments. */
10015 if (uses_template_parms (tmpl_args))
10017 /* Don't do this again for clones. */
10018 if (DECL_CLONED_FUNCTION_P (fn))
10021 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
10023 arg = TREE_CHAIN (arg))
10024 if (TREE_PURPOSE (arg))
10025 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
10027 TREE_PURPOSE (arg));
10030 /* Substitute the ARGS into the T, which is a _DECL. Return the
10031 result of the substitution. Issue error and warning messages under
10032 control of COMPLAIN. */
10035 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
10037 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
10038 location_t saved_loc;
10039 tree r = NULL_TREE;
10041 hashval_t hash = 0;
10043 /* Set the filename and linenumber to improve error-reporting. */
10044 saved_loc = input_location;
10045 input_location = DECL_SOURCE_LOCATION (t);
10047 switch (TREE_CODE (t))
10049 case TEMPLATE_DECL:
10051 /* We can get here when processing a member function template,
10052 member class template, or template template parameter. */
10053 tree decl = DECL_TEMPLATE_RESULT (t);
10058 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
10060 /* Template template parameter is treated here. */
10061 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10062 if (new_type == error_mark_node)
10063 RETURN (error_mark_node);
10066 DECL_CHAIN (r) = NULL_TREE;
10067 TREE_TYPE (r) = new_type;
10068 DECL_TEMPLATE_RESULT (r)
10069 = build_decl (DECL_SOURCE_LOCATION (decl),
10070 TYPE_DECL, DECL_NAME (decl), new_type);
10071 DECL_TEMPLATE_PARMS (r)
10072 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10074 TYPE_NAME (new_type) = r;
10078 /* We might already have an instance of this template.
10079 The ARGS are for the surrounding class type, so the
10080 full args contain the tsubst'd args for the context,
10081 plus the innermost args from the template decl. */
10082 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
10083 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
10084 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
10085 /* Because this is a template, the arguments will still be
10086 dependent, even after substitution. If
10087 PROCESSING_TEMPLATE_DECL is not set, the dependency
10088 predicates will short-circuit. */
10089 ++processing_template_decl;
10090 full_args = tsubst_template_args (tmpl_args, args,
10091 complain, in_decl);
10092 --processing_template_decl;
10093 if (full_args == error_mark_node)
10094 RETURN (error_mark_node);
10096 /* If this is a default template template argument,
10097 tsubst might not have changed anything. */
10098 if (full_args == tmpl_args)
10101 hash = hash_tmpl_and_args (t, full_args);
10102 spec = retrieve_specialization (t, full_args, hash);
10103 if (spec != NULL_TREE)
10109 /* Make a new template decl. It will be similar to the
10110 original, but will record the current template arguments.
10111 We also create a new function declaration, which is just
10112 like the old one, but points to this new template, rather
10113 than the old one. */
10115 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
10116 DECL_CHAIN (r) = NULL_TREE;
10118 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10120 if (TREE_CODE (decl) == TYPE_DECL
10121 && !TYPE_DECL_ALIAS_P (decl))
10124 ++processing_template_decl;
10125 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10126 --processing_template_decl;
10127 if (new_type == error_mark_node)
10128 RETURN (error_mark_node);
10130 TREE_TYPE (r) = new_type;
10131 CLASSTYPE_TI_TEMPLATE (new_type) = r;
10132 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
10133 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
10134 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
10139 ++processing_template_decl;
10140 new_decl = tsubst (decl, args, complain, in_decl);
10141 --processing_template_decl;
10142 if (new_decl == error_mark_node)
10143 RETURN (error_mark_node);
10145 DECL_TEMPLATE_RESULT (r) = new_decl;
10146 DECL_TI_TEMPLATE (new_decl) = r;
10147 TREE_TYPE (r) = TREE_TYPE (new_decl);
10148 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
10149 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
10152 SET_DECL_IMPLICIT_INSTANTIATION (r);
10153 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
10154 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
10156 /* The template parameters for this new template are all the
10157 template parameters for the old template, except the
10158 outermost level of parameters. */
10159 DECL_TEMPLATE_PARMS (r)
10160 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10163 if (PRIMARY_TEMPLATE_P (t))
10164 DECL_PRIMARY_TEMPLATE (r) = r;
10166 if (TREE_CODE (decl) != TYPE_DECL)
10167 /* Record this non-type partial instantiation. */
10168 register_specialization (r, t,
10169 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
10174 case FUNCTION_DECL:
10177 tree argvec = NULL_TREE;
10185 /* Nobody should be tsubst'ing into non-template functions. */
10186 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
10188 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
10193 /* If T is not dependent, just return it. We have to
10194 increment PROCESSING_TEMPLATE_DECL because
10195 value_dependent_expression_p assumes that nothing is
10196 dependent when PROCESSING_TEMPLATE_DECL is zero. */
10197 ++processing_template_decl;
10198 dependent_p = value_dependent_expression_p (t);
10199 --processing_template_decl;
10203 /* Calculate the most general template of which R is a
10204 specialization, and the complete set of arguments used to
10206 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
10207 argvec = tsubst_template_args (DECL_TI_ARGS
10208 (DECL_TEMPLATE_RESULT
10209 (DECL_TI_TEMPLATE (t))),
10210 args, complain, in_decl);
10211 if (argvec == error_mark_node)
10212 RETURN (error_mark_node);
10214 /* Check to see if we already have this specialization. */
10215 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10216 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10224 /* We can see more levels of arguments than parameters if
10225 there was a specialization of a member template, like
10228 template <class T> struct S { template <class U> void f(); }
10229 template <> template <class U> void S<int>::f(U);
10231 Here, we'll be substituting into the specialization,
10232 because that's where we can find the code we actually
10233 want to generate, but we'll have enough arguments for
10234 the most general template.
10236 We also deal with the peculiar case:
10238 template <class T> struct S {
10239 template <class U> friend void f();
10241 template <class U> void f() {}
10243 template void f<double>();
10245 Here, the ARGS for the instantiation of will be {int,
10246 double}. But, we only need as many ARGS as there are
10247 levels of template parameters in CODE_PATTERN. We are
10248 careful not to get fooled into reducing the ARGS in
10251 template <class T> struct S { template <class U> void f(U); }
10252 template <class T> template <> void S<T>::f(int) {}
10254 which we can spot because the pattern will be a
10255 specialization in this case. */
10256 args_depth = TMPL_ARGS_DEPTH (args);
10258 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
10259 if (args_depth > parms_depth
10260 && !DECL_TEMPLATE_SPECIALIZATION (t))
10261 args = get_innermost_template_args (args, parms_depth);
10265 /* This special case arises when we have something like this:
10267 template <class T> struct S {
10268 friend void f<int>(int, double);
10271 Here, the DECL_TI_TEMPLATE for the friend declaration
10272 will be an IDENTIFIER_NODE. We are being called from
10273 tsubst_friend_function, and we want only to create a
10274 new decl (R) with appropriate types so that we can call
10275 determine_specialization. */
10276 gen_tmpl = NULL_TREE;
10279 if (DECL_CLASS_SCOPE_P (t))
10281 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
10285 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
10286 complain, t, /*entering_scope=*/1);
10291 ctx = DECL_CONTEXT (t);
10293 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10294 if (type == error_mark_node)
10295 RETURN (error_mark_node);
10297 /* We do NOT check for matching decls pushed separately at this
10298 point, as they may not represent instantiations of this
10299 template, and in any case are considered separate under the
10302 DECL_USE_TEMPLATE (r) = 0;
10303 TREE_TYPE (r) = type;
10304 /* Clear out the mangled name and RTL for the instantiation. */
10305 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10306 SET_DECL_RTL (r, NULL);
10307 /* Leave DECL_INITIAL set on deleted instantiations. */
10308 if (!DECL_DELETED_FN (r))
10309 DECL_INITIAL (r) = NULL_TREE;
10310 DECL_CONTEXT (r) = ctx;
10312 if (member && DECL_CONV_FN_P (r))
10313 /* Type-conversion operator. Reconstruct the name, in
10314 case it's the name of one of the template's parameters. */
10315 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
10317 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
10319 DECL_RESULT (r) = NULL_TREE;
10321 TREE_STATIC (r) = 0;
10322 TREE_PUBLIC (r) = TREE_PUBLIC (t);
10323 DECL_EXTERNAL (r) = 1;
10324 /* If this is an instantiation of a function with internal
10325 linkage, we already know what object file linkage will be
10326 assigned to the instantiation. */
10327 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
10328 DECL_DEFER_OUTPUT (r) = 0;
10329 DECL_CHAIN (r) = NULL_TREE;
10330 DECL_PENDING_INLINE_INFO (r) = 0;
10331 DECL_PENDING_INLINE_P (r) = 0;
10332 DECL_SAVED_TREE (r) = NULL_TREE;
10333 DECL_STRUCT_FUNCTION (r) = NULL;
10335 /* We'll re-clone as appropriate in instantiate_template. */
10336 DECL_CLONED_FUNCTION (r) = NULL_TREE;
10338 /* If we aren't complaining now, return on error before we register
10339 the specialization so that we'll complain eventually. */
10340 if ((complain & tf_error) == 0
10341 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10342 && !grok_op_properties (r, /*complain=*/false))
10343 RETURN (error_mark_node);
10345 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
10346 this in the special friend case mentioned above where
10347 GEN_TMPL is NULL. */
10350 DECL_TEMPLATE_INFO (r)
10351 = build_template_info (gen_tmpl, argvec);
10352 SET_DECL_IMPLICIT_INSTANTIATION (r);
10353 register_specialization (r, gen_tmpl, argvec, false, hash);
10355 /* We're not supposed to instantiate default arguments
10356 until they are called, for a template. But, for a
10359 template <class T> void f ()
10360 { extern void g(int i = T()); }
10362 we should do the substitution when the template is
10363 instantiated. We handle the member function case in
10364 instantiate_class_template since the default arguments
10365 might refer to other members of the class. */
10367 && !PRIMARY_TEMPLATE_P (gen_tmpl)
10368 && !uses_template_parms (argvec))
10369 tsubst_default_arguments (r);
10372 DECL_TEMPLATE_INFO (r) = NULL_TREE;
10374 /* Copy the list of befriending classes. */
10375 for (friends = &DECL_BEFRIENDING_CLASSES (r);
10377 friends = &TREE_CHAIN (*friends))
10379 *friends = copy_node (*friends);
10380 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
10385 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
10387 maybe_retrofit_in_chrg (r);
10388 if (DECL_CONSTRUCTOR_P (r))
10389 grok_ctor_properties (ctx, r);
10390 /* If this is an instantiation of a member template, clone it.
10391 If it isn't, that'll be handled by
10392 clone_constructors_and_destructors. */
10393 if (PRIMARY_TEMPLATE_P (gen_tmpl))
10394 clone_function_decl (r, /*update_method_vec_p=*/0);
10396 else if ((complain & tf_error) != 0
10397 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10398 && !grok_op_properties (r, /*complain=*/true))
10399 RETURN (error_mark_node);
10401 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
10402 SET_DECL_FRIEND_CONTEXT (r,
10403 tsubst (DECL_FRIEND_CONTEXT (t),
10404 args, complain, in_decl));
10406 /* Possibly limit visibility based on template args. */
10407 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10408 if (DECL_VISIBILITY_SPECIFIED (t))
10410 DECL_VISIBILITY_SPECIFIED (r) = 0;
10411 DECL_ATTRIBUTES (r)
10412 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10414 determine_visibility (r);
10415 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
10416 && !processing_template_decl)
10417 defaulted_late_check (r);
10419 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10420 args, complain, in_decl);
10426 tree type = NULL_TREE;
10428 tree expanded_types = NULL_TREE;
10429 tree prev_r = NULL_TREE;
10430 tree first_r = NULL_TREE;
10432 if (FUNCTION_PARAMETER_PACK_P (t))
10434 /* If there is a local specialization that isn't a
10435 parameter pack, it means that we're doing a "simple"
10436 substitution from inside tsubst_pack_expansion. Just
10437 return the local specialization (which will be a single
10439 tree spec = retrieve_local_specialization (t);
10441 && TREE_CODE (spec) == PARM_DECL
10442 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
10445 /* Expand the TYPE_PACK_EXPANSION that provides the types for
10446 the parameters in this function parameter pack. */
10447 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
10448 complain, in_decl);
10449 if (TREE_CODE (expanded_types) == TREE_VEC)
10451 len = TREE_VEC_LENGTH (expanded_types);
10453 /* Zero-length parameter packs are boring. Just substitute
10456 RETURN (tsubst (TREE_CHAIN (t), args, complain,
10461 /* All we did was update the type. Make a note of that. */
10462 type = expanded_types;
10463 expanded_types = NULL_TREE;
10467 /* Loop through all of the parameter's we'll build. When T is
10468 a function parameter pack, LEN is the number of expanded
10469 types in EXPANDED_TYPES; otherwise, LEN is 1. */
10471 for (i = 0; i < len; ++i)
10475 if (DECL_TEMPLATE_PARM_P (t))
10476 SET_DECL_TEMPLATE_PARM_P (r);
10478 if (expanded_types)
10479 /* We're on the Ith parameter of the function parameter
10482 /* An argument of a function parameter pack is not a parameter
10484 FUNCTION_PARAMETER_PACK_P (r) = false;
10486 /* Get the Ith type. */
10487 type = TREE_VEC_ELT (expanded_types, i);
10490 /* Rename the parameter to include the index. */
10492 make_ith_pack_parameter_name (DECL_NAME (r), i);
10495 /* We're dealing with a normal parameter. */
10496 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10498 type = type_decays_to (type);
10499 TREE_TYPE (r) = type;
10500 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10502 if (DECL_INITIAL (r))
10504 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
10505 DECL_INITIAL (r) = TREE_TYPE (r);
10507 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
10508 complain, in_decl);
10511 DECL_CONTEXT (r) = NULL_TREE;
10513 if (!DECL_TEMPLATE_PARM_P (r))
10514 DECL_ARG_TYPE (r) = type_passed_as (type);
10516 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10517 args, complain, in_decl);
10519 /* Keep track of the first new parameter we
10520 generate. That's what will be returned to the
10525 /* Build a proper chain of parameters when substituting
10526 into a function parameter pack. */
10528 DECL_CHAIN (prev_r) = r;
10531 if (DECL_CHAIN (t))
10532 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
10533 complain, DECL_CHAIN (t));
10535 /* FIRST_R contains the start of the chain we've built. */
10545 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10546 if (type == error_mark_node)
10547 RETURN (error_mark_node);
10548 TREE_TYPE (r) = type;
10549 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10551 if (DECL_C_BIT_FIELD (r))
10552 /* For bit-fields, DECL_INITIAL gives the number of bits. For
10553 non-bit-fields DECL_INITIAL is a non-static data member
10554 initializer, which gets deferred instantiation. */
10556 = tsubst_expr (DECL_INITIAL (t), args,
10558 /*integral_constant_expression_p=*/true);
10559 else if (DECL_INITIAL (t))
10561 /* Set up DECL_TEMPLATE_INFO so that we can get at the
10562 NSDMI in perform_member_init. Still set DECL_INITIAL
10563 so that we know there is one. */
10564 DECL_INITIAL (r) = void_zero_node;
10565 gcc_assert (DECL_LANG_SPECIFIC (r) == NULL);
10566 retrofit_lang_decl (r);
10567 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10569 /* We don't have to set DECL_CONTEXT here; it is set by
10570 finish_member_declaration. */
10571 DECL_CHAIN (r) = NULL_TREE;
10572 if (VOID_TYPE_P (type))
10573 error ("instantiation of %q+D as type %qT", r, type);
10575 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10576 args, complain, in_decl);
10581 /* We reach here only for member using decls. */
10582 if (DECL_DEPENDENT_P (t))
10584 r = do_class_using_decl
10585 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
10586 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
10588 r = error_mark_node;
10591 TREE_PROTECTED (r) = TREE_PROTECTED (t);
10592 TREE_PRIVATE (r) = TREE_PRIVATE (t);
10598 DECL_CHAIN (r) = NULL_TREE;
10605 tree argvec = NULL_TREE;
10606 tree gen_tmpl = NULL_TREE;
10608 tree tmpl = NULL_TREE;
10610 tree type = NULL_TREE;
10613 if (TREE_CODE (t) == TYPE_DECL
10614 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
10616 /* If this is the canonical decl, we don't have to
10617 mess with instantiations, and often we can't (for
10618 typename, template type parms and such). Note that
10619 TYPE_NAME is not correct for the above test if
10620 we've copied the type for a typedef. */
10621 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10622 if (type == error_mark_node)
10623 RETURN (error_mark_node);
10624 r = TYPE_NAME (type);
10628 /* Check to see if we already have the specialization we
10631 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
10633 /* T is a static data member or namespace-scope entity.
10634 We have to substitute into namespace-scope variables
10635 (even though such entities are never templates) because
10638 template <class T> void f() { extern T t; }
10640 where the entity referenced is not known until
10641 instantiation time. */
10643 ctx = DECL_CONTEXT (t);
10644 if (DECL_CLASS_SCOPE_P (t))
10646 ctx = tsubst_aggr_type (ctx, args,
10648 in_decl, /*entering_scope=*/1);
10649 /* If CTX is unchanged, then T is in fact the
10650 specialization we want. That situation occurs when
10651 referencing a static data member within in its own
10652 class. We can use pointer equality, rather than
10653 same_type_p, because DECL_CONTEXT is always
10655 if (ctx == DECL_CONTEXT (t)
10656 && (TREE_CODE (t) != TYPE_DECL
10657 /* ... unless T is a member template; in which
10658 case our caller can be willing to create a
10659 specialization of that template represented
10661 || !(DECL_TI_TEMPLATE (t)
10662 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (t)))))
10668 tmpl = DECL_TI_TEMPLATE (t);
10669 gen_tmpl = most_general_template (tmpl);
10670 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
10671 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10672 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10677 /* A local variable. */
10679 /* Subsequent calls to pushdecl will fill this in. */
10681 spec = retrieve_local_specialization (t);
10683 /* If we already have the specialization we need, there is
10684 nothing more to do. */
10691 /* Create a new node for the specialization we need. */
10693 if (type == NULL_TREE)
10695 if (is_typedef_decl (t))
10696 type = DECL_ORIGINAL_TYPE (t);
10698 type = TREE_TYPE (t);
10699 if (TREE_CODE (t) == VAR_DECL
10700 && VAR_HAD_UNKNOWN_BOUND (t)
10701 && type != error_mark_node)
10702 type = strip_array_domain (type);
10703 type = tsubst (type, args, complain, in_decl);
10705 if (TREE_CODE (r) == VAR_DECL)
10707 /* Even if the original location is out of scope, the
10708 newly substituted one is not. */
10709 DECL_DEAD_FOR_LOCAL (r) = 0;
10710 DECL_INITIALIZED_P (r) = 0;
10711 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10712 if (type == error_mark_node)
10713 RETURN (error_mark_node);
10714 if (TREE_CODE (type) == FUNCTION_TYPE)
10716 /* It may seem that this case cannot occur, since:
10721 declares a function, not a variable. However:
10724 template <typename T> void g() { T t; }
10725 template void g<f>();
10727 is an attempt to declare a variable with function
10729 error ("variable %qD has function type",
10730 /* R is not yet sufficiently initialized, so we
10731 just use its name. */
10733 RETURN (error_mark_node);
10735 type = complete_type (type);
10736 /* Wait until cp_finish_decl to set this again, to handle
10737 circular dependency (template/instantiate6.C). */
10738 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10739 type = check_var_type (DECL_NAME (r), type);
10741 if (DECL_HAS_VALUE_EXPR_P (t))
10743 tree ve = DECL_VALUE_EXPR (t);
10744 ve = tsubst_expr (ve, args, complain, in_decl,
10745 /*constant_expression_p=*/false);
10746 if (REFERENCE_REF_P (ve))
10748 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
10749 ve = TREE_OPERAND (ve, 0);
10751 SET_DECL_VALUE_EXPR (r, ve);
10754 else if (DECL_SELF_REFERENCE_P (t))
10755 SET_DECL_SELF_REFERENCE_P (r);
10756 TREE_TYPE (r) = type;
10757 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10758 DECL_CONTEXT (r) = ctx;
10759 /* Clear out the mangled name and RTL for the instantiation. */
10760 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10761 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10762 SET_DECL_RTL (r, NULL);
10763 /* The initializer must not be expanded until it is required;
10764 see [temp.inst]. */
10765 DECL_INITIAL (r) = NULL_TREE;
10766 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10767 SET_DECL_RTL (r, NULL);
10768 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10769 if (TREE_CODE (r) == VAR_DECL)
10771 /* Possibly limit visibility based on template args. */
10772 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10773 if (DECL_VISIBILITY_SPECIFIED (t))
10775 DECL_VISIBILITY_SPECIFIED (r) = 0;
10776 DECL_ATTRIBUTES (r)
10777 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10779 determine_visibility (r);
10784 /* A static data member declaration is always marked
10785 external when it is declared in-class, even if an
10786 initializer is present. We mimic the non-template
10787 processing here. */
10788 DECL_EXTERNAL (r) = 1;
10790 register_specialization (r, gen_tmpl, argvec, false, hash);
10791 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10792 SET_DECL_IMPLICIT_INSTANTIATION (r);
10794 else if (cp_unevaluated_operand)
10796 /* We're substituting this var in a decltype outside of its
10797 scope, such as for a lambda return type. Don't add it to
10798 local_specializations, do perform auto deduction. */
10799 tree auto_node = type_uses_auto (type);
10803 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10804 /*constant_expression_p=*/false);
10805 init = resolve_nondeduced_context (init);
10806 TREE_TYPE (r) = type
10807 = do_auto_deduction (type, init, auto_node);
10811 register_local_specialization (r, t);
10813 DECL_CHAIN (r) = NULL_TREE;
10815 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10817 args, complain, in_decl);
10819 /* Preserve a typedef that names a type. */
10820 if (is_typedef_decl (r))
10822 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10823 set_underlying_type (r);
10826 layout_decl (r, 0);
10831 gcc_unreachable ();
10836 /* Restore the file and line information. */
10837 input_location = saved_loc;
10842 /* Substitute into the ARG_TYPES of a function type. */
10845 tsubst_arg_types (tree arg_types,
10847 tsubst_flags_t complain,
10850 tree remaining_arg_types;
10851 tree type = NULL_TREE;
10853 tree expanded_args = NULL_TREE;
10856 if (!arg_types || arg_types == void_list_node)
10859 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10860 args, complain, in_decl);
10861 if (remaining_arg_types == error_mark_node)
10862 return error_mark_node;
10864 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10866 /* For a pack expansion, perform substitution on the
10867 entire expression. Later on, we'll handle the arguments
10869 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10870 args, complain, in_decl);
10872 if (TREE_CODE (expanded_args) == TREE_VEC)
10873 /* So that we'll spin through the parameters, one by one. */
10874 i = TREE_VEC_LENGTH (expanded_args);
10877 /* We only partially substituted into the parameter
10878 pack. Our type is TYPE_PACK_EXPANSION. */
10879 type = expanded_args;
10880 expanded_args = NULL_TREE;
10888 type = TREE_VEC_ELT (expanded_args, i);
10890 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10892 if (type == error_mark_node)
10893 return error_mark_node;
10894 if (VOID_TYPE_P (type))
10896 if (complain & tf_error)
10898 error ("invalid parameter type %qT", type);
10900 error ("in declaration %q+D", in_decl);
10902 return error_mark_node;
10905 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10906 top-level qualifiers as required. */
10907 type = cv_unqualified (type_decays_to (type));
10909 /* We do not substitute into default arguments here. The standard
10910 mandates that they be instantiated only when needed, which is
10911 done in build_over_call. */
10912 default_arg = TREE_PURPOSE (arg_types);
10914 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10916 /* We've instantiated a template before its default arguments
10917 have been parsed. This can happen for a nested template
10918 class, and is not an error unless we require the default
10919 argument in a call of this function. */
10920 remaining_arg_types =
10921 tree_cons (default_arg, type, remaining_arg_types);
10922 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
10923 remaining_arg_types);
10926 remaining_arg_types =
10927 hash_tree_cons (default_arg, type, remaining_arg_types);
10930 return remaining_arg_types;
10933 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10934 *not* handle the exception-specification for FNTYPE, because the
10935 initial substitution of explicitly provided template parameters
10936 during argument deduction forbids substitution into the
10937 exception-specification:
10941 All references in the function type of the function template to the
10942 corresponding template parameters are replaced by the specified tem-
10943 plate argument values. If a substitution in a template parameter or
10944 in the function type of the function template results in an invalid
10945 type, type deduction fails. [Note: The equivalent substitution in
10946 exception specifications is done only when the function is instanti-
10947 ated, at which point a program is ill-formed if the substitution
10948 results in an invalid type.] */
10951 tsubst_function_type (tree t,
10953 tsubst_flags_t complain,
10960 /* The TYPE_CONTEXT is not used for function/method types. */
10961 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10963 /* Substitute the return type. */
10964 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10965 if (return_type == error_mark_node)
10966 return error_mark_node;
10967 /* The standard does not presently indicate that creation of a
10968 function type with an invalid return type is a deduction failure.
10969 However, that is clearly analogous to creating an array of "void"
10970 or a reference to a reference. This is core issue #486. */
10971 if (TREE_CODE (return_type) == ARRAY_TYPE
10972 || TREE_CODE (return_type) == FUNCTION_TYPE)
10974 if (complain & tf_error)
10976 if (TREE_CODE (return_type) == ARRAY_TYPE)
10977 error ("function returning an array");
10979 error ("function returning a function");
10981 return error_mark_node;
10984 /* Substitute the argument types. */
10985 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
10986 complain, in_decl);
10987 if (arg_types == error_mark_node)
10988 return error_mark_node;
10990 /* Construct a new type node and return it. */
10991 if (TREE_CODE (t) == FUNCTION_TYPE)
10993 fntype = build_function_type (return_type, arg_types);
10994 fntype = apply_memfn_quals (fntype, type_memfn_quals (t));
10998 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10999 if (! MAYBE_CLASS_TYPE_P (r))
11003 Type deduction may fail for any of the following
11006 -- Attempting to create "pointer to member of T" when T
11007 is not a class type. */
11008 if (complain & tf_error)
11009 error ("creating pointer to member function of non-class type %qT",
11011 return error_mark_node;
11014 fntype = build_method_type_directly (r, return_type,
11015 TREE_CHAIN (arg_types));
11017 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
11022 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
11023 ARGS into that specification, and return the substituted
11024 specification. If there is no specification, return NULL_TREE. */
11027 tsubst_exception_specification (tree fntype,
11029 tsubst_flags_t complain,
11036 specs = TYPE_RAISES_EXCEPTIONS (fntype);
11037 new_specs = NULL_TREE;
11038 if (specs && TREE_PURPOSE (specs))
11040 /* A noexcept-specifier. */
11041 tree expr = TREE_PURPOSE (specs);
11042 if (expr == boolean_true_node || expr == boolean_false_node)
11046 /* Defer instantiation of noexcept-specifiers to avoid
11047 excessive instantiations (c++/49107). */
11048 new_specs = make_node (DEFERRED_NOEXCEPT);
11049 if (DEFERRED_NOEXCEPT_SPEC_P (specs))
11051 /* We already partially instantiated this member template,
11052 so combine the new args with the old. */
11053 DEFERRED_NOEXCEPT_PATTERN (new_specs)
11054 = DEFERRED_NOEXCEPT_PATTERN (expr);
11055 DEFERRED_NOEXCEPT_ARGS (new_specs)
11056 = add_to_template_args (DEFERRED_NOEXCEPT_ARGS (expr), args);
11060 DEFERRED_NOEXCEPT_PATTERN (new_specs) = expr;
11061 DEFERRED_NOEXCEPT_ARGS (new_specs) = args;
11065 new_specs = tsubst_copy_and_build
11066 (expr, args, complain, in_decl, /*function_p=*/false,
11067 /*integral_constant_expression_p=*/true);
11068 new_specs = build_noexcept_spec (new_specs, complain);
11072 if (! TREE_VALUE (specs))
11079 tree expanded_specs = NULL_TREE;
11081 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
11083 /* Expand the pack expansion type. */
11084 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
11088 if (expanded_specs == error_mark_node)
11089 return error_mark_node;
11090 else if (TREE_CODE (expanded_specs) == TREE_VEC)
11091 len = TREE_VEC_LENGTH (expanded_specs);
11094 /* We're substituting into a member template, so
11095 we got a TYPE_PACK_EXPANSION back. Add that
11096 expansion and move on. */
11097 gcc_assert (TREE_CODE (expanded_specs)
11098 == TYPE_PACK_EXPANSION);
11099 new_specs = add_exception_specifier (new_specs,
11102 specs = TREE_CHAIN (specs);
11107 for (i = 0; i < len; ++i)
11109 if (expanded_specs)
11110 spec = TREE_VEC_ELT (expanded_specs, i);
11112 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
11113 if (spec == error_mark_node)
11115 new_specs = add_exception_specifier (new_specs, spec,
11119 specs = TREE_CHAIN (specs);
11125 /* Take the tree structure T and replace template parameters used
11126 therein with the argument vector ARGS. IN_DECL is an associated
11127 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
11128 Issue error and warning messages under control of COMPLAIN. Note
11129 that we must be relatively non-tolerant of extensions here, in
11130 order to preserve conformance; if we allow substitutions that
11131 should not be allowed, we may allow argument deductions that should
11132 not succeed, and therefore report ambiguous overload situations
11133 where there are none. In theory, we could allow the substitution,
11134 but indicate that it should have failed, and allow our caller to
11135 make sure that the right thing happens, but we don't try to do this
11138 This function is used for dealing with types, decls and the like;
11139 for expressions, use tsubst_expr or tsubst_copy. */
11142 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11144 enum tree_code code;
11145 tree type, r = NULL_TREE;
11147 if (t == NULL_TREE || t == error_mark_node
11148 || t == integer_type_node
11149 || t == void_type_node
11150 || t == char_type_node
11151 || t == unknown_type_node
11152 || TREE_CODE (t) == NAMESPACE_DECL
11153 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
11157 return tsubst_decl (t, args, complain);
11159 if (args == NULL_TREE)
11162 code = TREE_CODE (t);
11164 if (code == IDENTIFIER_NODE)
11165 type = IDENTIFIER_TYPE_VALUE (t);
11167 type = TREE_TYPE (t);
11169 gcc_assert (type != unknown_type_node);
11171 /* Reuse typedefs. We need to do this to handle dependent attributes,
11172 such as attribute aligned. */
11174 && typedef_variant_p (t))
11176 tree decl = TYPE_NAME (t);
11178 if (TYPE_DECL_ALIAS_P (decl)
11179 && DECL_LANG_SPECIFIC (decl)
11180 && DECL_TEMPLATE_INFO (decl)
11181 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl)))
11183 /* DECL represents an alias template and we want to
11184 instantiate it. Let's substitute our arguments for the
11185 template parameters into the declaration and get the
11187 r = tsubst (decl, args, complain, decl);
11189 else if (DECL_CLASS_SCOPE_P (decl)
11190 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
11191 && uses_template_parms (DECL_CONTEXT (decl)))
11193 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11194 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
11195 r = retrieve_specialization (tmpl, gen_args, 0);
11197 else if (DECL_FUNCTION_SCOPE_P (decl)
11198 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
11199 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
11200 r = retrieve_local_specialization (decl);
11202 /* The typedef is from a non-template context. */
11208 r = cp_build_qualified_type_real
11209 (r, cp_type_quals (t) | cp_type_quals (r),
11210 complain | tf_ignore_bad_quals);
11214 /* We don't have an instantiation yet, so drop the typedef. */
11215 t = DECL_ORIGINAL_TYPE (decl);
11219 && code != TYPENAME_TYPE
11220 && code != TEMPLATE_TYPE_PARM
11221 && code != IDENTIFIER_NODE
11222 && code != FUNCTION_TYPE
11223 && code != METHOD_TYPE)
11224 type = tsubst (type, args, complain, in_decl);
11225 if (type == error_mark_node)
11226 return error_mark_node;
11232 case ENUMERAL_TYPE:
11233 return tsubst_aggr_type (t, args, complain, in_decl,
11234 /*entering_scope=*/0);
11237 case IDENTIFIER_NODE:
11248 if (t == integer_type_node)
11251 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
11252 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
11256 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
11258 max = tsubst_expr (omax, args, complain, in_decl,
11259 /*integral_constant_expression_p=*/false);
11261 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
11263 if (TREE_CODE (max) == NOP_EXPR
11264 && TREE_SIDE_EFFECTS (omax)
11265 && !TREE_TYPE (max))
11266 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
11268 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
11269 with TREE_SIDE_EFFECTS that indicates this is not an integral
11270 constant expression. */
11271 if (processing_template_decl
11272 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
11274 gcc_assert (TREE_CODE (max) == NOP_EXPR);
11275 TREE_SIDE_EFFECTS (max) = 1;
11278 return compute_array_index_type (NULL_TREE, max, complain);
11281 case TEMPLATE_TYPE_PARM:
11282 case TEMPLATE_TEMPLATE_PARM:
11283 case BOUND_TEMPLATE_TEMPLATE_PARM:
11284 case TEMPLATE_PARM_INDEX:
11289 tree arg = NULL_TREE;
11293 gcc_assert (TREE_VEC_LENGTH (args) > 0);
11294 template_parm_level_and_index (t, &level, &idx);
11296 levels = TMPL_ARGS_DEPTH (args);
11297 if (level <= levels)
11299 arg = TMPL_ARG (args, level, idx);
11301 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
11302 /* See through ARGUMENT_PACK_SELECT arguments. */
11303 arg = ARGUMENT_PACK_SELECT_ARG (arg);
11306 if (arg == error_mark_node)
11307 return error_mark_node;
11308 else if (arg != NULL_TREE)
11310 if (ARGUMENT_PACK_P (arg))
11311 /* If ARG is an argument pack, we don't actually want to
11312 perform a substitution here, because substitutions
11313 for argument packs are only done
11314 element-by-element. We can get to this point when
11315 substituting the type of a non-type template
11316 parameter pack, when that type actually contains
11317 template parameter packs from an outer template, e.g.,
11319 template<typename... Types> struct A {
11320 template<Types... Values> struct B { };
11324 if (code == TEMPLATE_TYPE_PARM)
11327 gcc_assert (TYPE_P (arg));
11329 quals = cp_type_quals (arg) | cp_type_quals (t);
11331 return cp_build_qualified_type_real
11332 (arg, quals, complain | tf_ignore_bad_quals);
11334 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11336 /* We are processing a type constructed from a
11337 template template parameter. */
11338 tree argvec = tsubst (TYPE_TI_ARGS (t),
11339 args, complain, in_decl);
11340 if (argvec == error_mark_node)
11341 return error_mark_node;
11343 gcc_assert (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
11344 || TREE_CODE (arg) == TEMPLATE_DECL
11345 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
11347 if (TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE)
11348 /* Consider this code:
11350 template <template <class> class Template>
11352 template <class Arg> using Bind = Template<Arg>;
11355 template <template <class> class Template, class Arg>
11356 using Instantiate = Template<Arg>; //#0
11358 template <template <class> class Template,
11361 Instantiate<Internal<Template>::template Bind,
11364 When #1 is parsed, the
11365 BOUND_TEMPLATE_TEMPLATE_PARM representing the
11366 parameter `Template' in #0 matches the
11367 UNBOUND_CLASS_TEMPLATE representing the argument
11368 `Internal<Template>::template Bind'; We then want
11369 to assemble the type `Bind<Argument>' that can't
11370 be fully created right now, because
11371 `Internal<Template>' not being complete, the Bind
11372 template cannot be looked up in that context. So
11373 we need to "store" `Bind<Argument>' for later
11374 when the context of Bind becomes complete. Let's
11375 store that in a TYPENAME_TYPE. */
11376 return make_typename_type (TYPE_CONTEXT (arg),
11377 build_nt (TEMPLATE_ID_EXPR,
11378 TYPE_IDENTIFIER (arg),
11383 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
11384 are resolving nested-types in the signature of a
11385 member function templates. Otherwise ARG is a
11386 TEMPLATE_DECL and is the real template to be
11388 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11389 arg = TYPE_NAME (arg);
11391 r = lookup_template_class (arg,
11393 DECL_CONTEXT (arg),
11394 /*entering_scope=*/0,
11396 return cp_build_qualified_type_real
11397 (r, cp_type_quals (t), complain);
11400 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
11401 return convert_from_reference (unshare_expr (arg));
11405 /* This can happen during the attempted tsubst'ing in
11406 unify. This means that we don't yet have any information
11407 about the template parameter in question. */
11410 /* If we get here, we must have been looking at a parm for a
11411 more deeply nested template. Make a new version of this
11412 template parameter, but with a lower level. */
11415 case TEMPLATE_TYPE_PARM:
11416 case TEMPLATE_TEMPLATE_PARM:
11417 case BOUND_TEMPLATE_TEMPLATE_PARM:
11418 if (cp_type_quals (t))
11420 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
11421 r = cp_build_qualified_type_real
11422 (r, cp_type_quals (t),
11423 complain | (code == TEMPLATE_TYPE_PARM
11424 ? tf_ignore_bad_quals : 0));
11429 TEMPLATE_TYPE_PARM_INDEX (r)
11430 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
11431 r, levels, args, complain);
11432 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
11433 TYPE_MAIN_VARIANT (r) = r;
11434 TYPE_POINTER_TO (r) = NULL_TREE;
11435 TYPE_REFERENCE_TO (r) = NULL_TREE;
11437 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
11438 /* We have reduced the level of the template
11439 template parameter, but not the levels of its
11440 template parameters, so canonical_type_parameter
11441 will not be able to find the canonical template
11442 template parameter for this level. Thus, we
11443 require structural equality checking to compare
11444 TEMPLATE_TEMPLATE_PARMs. */
11445 SET_TYPE_STRUCTURAL_EQUALITY (r);
11446 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
11447 SET_TYPE_STRUCTURAL_EQUALITY (r);
11449 TYPE_CANONICAL (r) = canonical_type_parameter (r);
11451 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11453 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
11454 complain, in_decl);
11455 if (argvec == error_mark_node)
11456 return error_mark_node;
11458 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
11459 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
11464 case TEMPLATE_PARM_INDEX:
11465 r = reduce_template_parm_level (t, type, levels, args, complain);
11469 gcc_unreachable ();
11477 tree purpose, value, chain;
11479 if (t == void_list_node)
11482 purpose = TREE_PURPOSE (t);
11485 purpose = tsubst (purpose, args, complain, in_decl);
11486 if (purpose == error_mark_node)
11487 return error_mark_node;
11489 value = TREE_VALUE (t);
11492 value = tsubst (value, args, complain, in_decl);
11493 if (value == error_mark_node)
11494 return error_mark_node;
11496 chain = TREE_CHAIN (t);
11497 if (chain && chain != void_type_node)
11499 chain = tsubst (chain, args, complain, in_decl);
11500 if (chain == error_mark_node)
11501 return error_mark_node;
11503 if (purpose == TREE_PURPOSE (t)
11504 && value == TREE_VALUE (t)
11505 && chain == TREE_CHAIN (t))
11507 return hash_tree_cons (purpose, value, chain);
11511 /* We should never be tsubsting a binfo. */
11512 gcc_unreachable ();
11515 /* A vector of template arguments. */
11516 gcc_assert (!type);
11517 return tsubst_template_args (t, args, complain, in_decl);
11520 case REFERENCE_TYPE:
11522 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
11527 Type deduction may fail for any of the following
11530 -- Attempting to create a pointer to reference type.
11531 -- Attempting to create a reference to a reference type or
11532 a reference to void.
11534 Core issue 106 says that creating a reference to a reference
11535 during instantiation is no longer a cause for failure. We
11536 only enforce this check in strict C++98 mode. */
11537 if ((TREE_CODE (type) == REFERENCE_TYPE
11538 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
11539 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
11541 static location_t last_loc;
11543 /* We keep track of the last time we issued this error
11544 message to avoid spewing a ton of messages during a
11545 single bad template instantiation. */
11546 if (complain & tf_error
11547 && last_loc != input_location)
11549 if (TREE_CODE (type) == VOID_TYPE)
11550 error ("forming reference to void");
11551 else if (code == POINTER_TYPE)
11552 error ("forming pointer to reference type %qT", type);
11554 error ("forming reference to reference type %qT", type);
11555 last_loc = input_location;
11558 return error_mark_node;
11560 else if (code == POINTER_TYPE)
11562 r = build_pointer_type (type);
11563 if (TREE_CODE (type) == METHOD_TYPE)
11564 r = build_ptrmemfunc_type (r);
11566 else if (TREE_CODE (type) == REFERENCE_TYPE)
11567 /* In C++0x, during template argument substitution, when there is an
11568 attempt to create a reference to a reference type, reference
11569 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
11571 "If a template-argument for a template-parameter T names a type
11572 that is a reference to a type A, an attempt to create the type
11573 'lvalue reference to cv T' creates the type 'lvalue reference to
11574 A,' while an attempt to create the type type rvalue reference to
11575 cv T' creates the type T"
11577 r = cp_build_reference_type
11579 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
11581 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
11582 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
11584 if (r != error_mark_node)
11585 /* Will this ever be needed for TYPE_..._TO values? */
11592 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
11593 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
11597 Type deduction may fail for any of the following
11600 -- Attempting to create "pointer to member of T" when T
11601 is not a class type. */
11602 if (complain & tf_error)
11603 error ("creating pointer to member of non-class type %qT", r);
11604 return error_mark_node;
11606 if (TREE_CODE (type) == REFERENCE_TYPE)
11608 if (complain & tf_error)
11609 error ("creating pointer to member reference type %qT", type);
11610 return error_mark_node;
11612 if (TREE_CODE (type) == VOID_TYPE)
11614 if (complain & tf_error)
11615 error ("creating pointer to member of type void");
11616 return error_mark_node;
11618 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
11619 if (TREE_CODE (type) == FUNCTION_TYPE)
11621 /* The type of the implicit object parameter gets its
11622 cv-qualifiers from the FUNCTION_TYPE. */
11624 tree method_type = build_memfn_type (type, r, type_memfn_quals (type));
11625 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
11626 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
11630 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
11634 case FUNCTION_TYPE:
11639 fntype = tsubst_function_type (t, args, complain, in_decl);
11640 if (fntype == error_mark_node)
11641 return error_mark_node;
11643 /* Substitute the exception specification. */
11644 specs = tsubst_exception_specification (t, args, complain,
11645 in_decl, /*defer_ok*/true);
11646 if (specs == error_mark_node)
11647 return error_mark_node;
11649 fntype = build_exception_variant (fntype, specs);
11654 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
11655 if (domain == error_mark_node)
11656 return error_mark_node;
11658 /* As an optimization, we avoid regenerating the array type if
11659 it will obviously be the same as T. */
11660 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
11663 /* These checks should match the ones in grokdeclarator.
11667 The deduction may fail for any of the following reasons:
11669 -- Attempting to create an array with an element type that
11670 is void, a function type, or a reference type, or [DR337]
11671 an abstract class type. */
11672 if (TREE_CODE (type) == VOID_TYPE
11673 || TREE_CODE (type) == FUNCTION_TYPE
11674 || TREE_CODE (type) == REFERENCE_TYPE)
11676 if (complain & tf_error)
11677 error ("creating array of %qT", type);
11678 return error_mark_node;
11680 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
11682 if (complain & tf_error)
11683 error ("creating array of %qT, which is an abstract class type",
11685 return error_mark_node;
11688 r = build_cplus_array_type (type, domain);
11690 if (TYPE_USER_ALIGN (t))
11692 TYPE_ALIGN (r) = TYPE_ALIGN (t);
11693 TYPE_USER_ALIGN (r) = 1;
11699 case TYPENAME_TYPE:
11701 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11702 in_decl, /*entering_scope=*/1);
11703 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
11704 complain, in_decl);
11706 if (ctx == error_mark_node || f == error_mark_node)
11707 return error_mark_node;
11709 if (!MAYBE_CLASS_TYPE_P (ctx))
11711 if (complain & tf_error)
11712 error ("%qT is not a class, struct, or union type", ctx);
11713 return error_mark_node;
11715 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
11717 /* Normally, make_typename_type does not require that the CTX
11718 have complete type in order to allow things like:
11720 template <class T> struct S { typename S<T>::X Y; };
11722 But, such constructs have already been resolved by this
11723 point, so here CTX really should have complete type, unless
11724 it's a partial instantiation. */
11725 ctx = complete_type (ctx);
11726 if (!COMPLETE_TYPE_P (ctx))
11728 if (complain & tf_error)
11729 cxx_incomplete_type_error (NULL_TREE, ctx);
11730 return error_mark_node;
11734 f = make_typename_type (ctx, f, typename_type,
11735 (complain & tf_error) | tf_keep_type_decl);
11736 if (f == error_mark_node)
11738 if (TREE_CODE (f) == TYPE_DECL)
11740 complain |= tf_ignore_bad_quals;
11744 if (TREE_CODE (f) != TYPENAME_TYPE)
11746 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
11748 if (complain & tf_error)
11749 error ("%qT resolves to %qT, which is not an enumeration type",
11752 return error_mark_node;
11754 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
11756 if (complain & tf_error)
11757 error ("%qT resolves to %qT, which is is not a class type",
11760 return error_mark_node;
11764 return cp_build_qualified_type_real
11765 (f, cp_type_quals (f) | cp_type_quals (t), complain);
11768 case UNBOUND_CLASS_TEMPLATE:
11770 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11771 in_decl, /*entering_scope=*/1);
11772 tree name = TYPE_IDENTIFIER (t);
11773 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11775 if (ctx == error_mark_node || name == error_mark_node)
11776 return error_mark_node;
11779 parm_list = tsubst_template_parms (parm_list, args, complain);
11780 return make_unbound_class_template (ctx, name, parm_list, complain);
11787 ++cp_unevaluated_operand;
11788 ++c_inhibit_evaluation_warnings;
11790 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11792 /*integral_constant_expression_p=*/false);
11794 --cp_unevaluated_operand;
11795 --c_inhibit_evaluation_warnings;
11797 type = finish_typeof (type);
11798 return cp_build_qualified_type_real (type,
11800 | cp_type_quals (type),
11804 case DECLTYPE_TYPE:
11808 ++cp_unevaluated_operand;
11809 ++c_inhibit_evaluation_warnings;
11811 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11813 /*integral_constant_expression_p=*/false);
11815 --cp_unevaluated_operand;
11816 --c_inhibit_evaluation_warnings;
11818 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11819 type = lambda_capture_field_type (type);
11820 else if (DECLTYPE_FOR_LAMBDA_PROXY (t))
11821 type = lambda_proxy_type (type);
11823 type = finish_decltype_type
11824 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain);
11825 return cp_build_qualified_type_real (type,
11827 | cp_type_quals (type),
11831 case UNDERLYING_TYPE:
11833 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11834 complain, in_decl);
11835 return finish_underlying_type (type);
11838 case TYPE_ARGUMENT_PACK:
11839 case NONTYPE_ARGUMENT_PACK:
11841 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11843 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11847 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11849 /* For template nontype argument packs, also substitute into
11851 if (code == NONTYPE_ARGUMENT_PACK)
11852 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11870 /* We should use one of the expression tsubsts for these codes. */
11871 gcc_unreachable ();
11874 sorry ("use of %qs in template", tree_code_name [(int) code]);
11875 return error_mark_node;
11879 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11880 type of the expression on the left-hand side of the "." or "->"
11884 tsubst_baselink (tree baselink, tree object_type,
11885 tree args, tsubst_flags_t complain, tree in_decl)
11888 tree qualifying_scope;
11891 tree template_args = 0;
11892 bool template_id_p = false;
11893 bool qualified = BASELINK_QUALIFIED_P (baselink);
11895 /* A baselink indicates a function from a base class. Both the
11896 BASELINK_ACCESS_BINFO and the base class referenced may
11897 indicate bases of the template class, rather than the
11898 instantiated class. In addition, lookups that were not
11899 ambiguous before may be ambiguous now. Therefore, we perform
11900 the lookup again. */
11901 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11902 qualifying_scope = tsubst (qualifying_scope, args,
11903 complain, in_decl);
11904 fns = BASELINK_FUNCTIONS (baselink);
11905 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11906 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11908 template_id_p = true;
11909 template_args = TREE_OPERAND (fns, 1);
11910 fns = TREE_OPERAND (fns, 0);
11912 template_args = tsubst_template_args (template_args, args,
11913 complain, in_decl);
11915 name = DECL_NAME (get_first_fn (fns));
11916 if (IDENTIFIER_TYPENAME_P (name))
11917 name = mangle_conv_op_name_for_type (optype);
11918 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11920 return error_mark_node;
11922 /* If lookup found a single function, mark it as used at this
11923 point. (If it lookup found multiple functions the one selected
11924 later by overload resolution will be marked as used at that
11926 if (BASELINK_P (baselink))
11927 fns = BASELINK_FUNCTIONS (baselink);
11928 if (!template_id_p && !really_overloaded_fn (fns))
11929 mark_used (OVL_CURRENT (fns));
11931 /* Add back the template arguments, if present. */
11932 if (BASELINK_P (baselink) && template_id_p)
11933 BASELINK_FUNCTIONS (baselink)
11934 = build_nt (TEMPLATE_ID_EXPR,
11935 BASELINK_FUNCTIONS (baselink),
11937 /* Update the conversion operator type. */
11938 BASELINK_OPTYPE (baselink) = optype;
11941 object_type = current_class_type;
11944 baselink = adjust_result_of_qualified_name_lookup (baselink,
11950 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11951 true if the qualified-id will be a postfix-expression in-and-of
11952 itself; false if more of the postfix-expression follows the
11953 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11957 tsubst_qualified_id (tree qualified_id, tree args,
11958 tsubst_flags_t complain, tree in_decl,
11959 bool done, bool address_p)
11965 tree template_args;
11967 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11969 /* Figure out what name to look up. */
11970 name = TREE_OPERAND (qualified_id, 1);
11971 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11973 is_template = true;
11974 template_args = TREE_OPERAND (name, 1);
11976 template_args = tsubst_template_args (template_args, args,
11977 complain, in_decl);
11978 name = TREE_OPERAND (name, 0);
11982 is_template = false;
11983 template_args = NULL_TREE;
11986 /* Substitute into the qualifying scope. When there are no ARGS, we
11987 are just trying to simplify a non-dependent expression. In that
11988 case the qualifying scope may be dependent, and, in any case,
11989 substituting will not help. */
11990 scope = TREE_OPERAND (qualified_id, 0);
11993 scope = tsubst (scope, args, complain, in_decl);
11994 expr = tsubst_copy (name, args, complain, in_decl);
11999 if (dependent_scope_p (scope))
12002 expr = build_min_nt (TEMPLATE_ID_EXPR, expr, template_args);
12003 return build_qualified_name (NULL_TREE, scope, expr,
12004 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
12007 if (!BASELINK_P (name) && !DECL_P (expr))
12009 if (TREE_CODE (expr) == BIT_NOT_EXPR)
12011 /* A BIT_NOT_EXPR is used to represent a destructor. */
12012 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
12014 error ("qualifying type %qT does not match destructor name ~%qT",
12015 scope, TREE_OPERAND (expr, 0));
12016 expr = error_mark_node;
12019 expr = lookup_qualified_name (scope, complete_dtor_identifier,
12020 /*is_type_p=*/0, false);
12023 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
12024 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
12025 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
12027 if (complain & tf_error)
12029 error ("dependent-name %qE is parsed as a non-type, but "
12030 "instantiation yields a type", qualified_id);
12031 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
12033 return error_mark_node;
12039 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
12041 /* Remember that there was a reference to this entity. */
12045 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
12047 if (complain & tf_error)
12048 qualified_name_lookup_error (scope,
12049 TREE_OPERAND (qualified_id, 1),
12050 expr, input_location);
12051 return error_mark_node;
12055 expr = lookup_template_function (expr, template_args);
12057 if (expr == error_mark_node && complain & tf_error)
12058 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
12059 expr, input_location);
12060 else if (TYPE_P (scope))
12062 expr = (adjust_result_of_qualified_name_lookup
12063 (expr, scope, current_class_type));
12064 expr = (finish_qualified_id_expr
12065 (scope, expr, done, address_p && PTRMEM_OK_P (qualified_id),
12066 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
12067 /*template_arg_p=*/false));
12070 /* Expressions do not generally have reference type. */
12071 if (TREE_CODE (expr) != SCOPE_REF
12072 /* However, if we're about to form a pointer-to-member, we just
12073 want the referenced member referenced. */
12074 && TREE_CODE (expr) != OFFSET_REF)
12075 expr = convert_from_reference (expr);
12080 /* Like tsubst, but deals with expressions. This function just replaces
12081 template parms; to finish processing the resultant expression, use
12082 tsubst_copy_and_build or tsubst_expr. */
12085 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
12087 enum tree_code code;
12090 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
12093 code = TREE_CODE (t);
12098 r = retrieve_local_specialization (t);
12104 /* We get here for a use of 'this' in an NSDMI. */
12105 if (DECL_NAME (t) == this_identifier
12106 && at_function_scope_p ()
12107 && DECL_CONSTRUCTOR_P (current_function_decl))
12108 return current_class_ptr;
12110 /* This can happen for a parameter name used later in a function
12111 declaration (such as in a late-specified return type). Just
12112 make a dummy decl, since it's only used for its type. */
12113 gcc_assert (cp_unevaluated_operand != 0);
12114 /* We copy T because want to tsubst the PARM_DECL only,
12115 not the following PARM_DECLs that are chained to T. */
12117 r = tsubst_decl (c, args, complain);
12118 /* Give it the template pattern as its context; its true context
12119 hasn't been instantiated yet and this is good enough for
12121 DECL_CONTEXT (r) = DECL_CONTEXT (t);
12124 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
12125 r = ARGUMENT_PACK_SELECT_ARG (r);
12134 if (DECL_TEMPLATE_PARM_P (t))
12135 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
12136 /* There is no need to substitute into namespace-scope
12138 if (DECL_NAMESPACE_SCOPE_P (t))
12140 /* If ARGS is NULL, then T is known to be non-dependent. */
12141 if (args == NULL_TREE)
12142 return integral_constant_value (t);
12144 /* Unfortunately, we cannot just call lookup_name here.
12147 template <int I> int f() {
12149 struct S { void g() { E e = a; } };
12152 When we instantiate f<7>::S::g(), say, lookup_name is not
12153 clever enough to find f<7>::a. */
12155 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
12156 /*entering_scope=*/0);
12158 for (v = TYPE_VALUES (enum_type);
12160 v = TREE_CHAIN (v))
12161 if (TREE_PURPOSE (v) == DECL_NAME (t))
12162 return TREE_VALUE (v);
12164 /* We didn't find the name. That should never happen; if
12165 name-lookup found it during preliminary parsing, we
12166 should find it again here during instantiation. */
12167 gcc_unreachable ();
12172 if (DECL_CONTEXT (t))
12176 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
12177 /*entering_scope=*/1);
12178 if (ctx != DECL_CONTEXT (t))
12180 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
12183 if (complain & tf_error)
12184 error ("using invalid field %qD", t);
12185 return error_mark_node;
12194 case FUNCTION_DECL:
12195 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
12196 || local_variable_p (t))
12197 t = tsubst (t, args, complain, in_decl);
12201 case NAMESPACE_DECL:
12205 /* An OVERLOAD will always be a non-dependent overload set; an
12206 overload set from function scope will just be represented with an
12207 IDENTIFIER_NODE, and from class scope with a BASELINK. */
12208 gcc_assert (!uses_template_parms (t));
12212 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
12214 case TEMPLATE_DECL:
12215 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
12216 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
12217 args, complain, in_decl);
12218 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
12219 return tsubst (t, args, complain, in_decl);
12220 else if (DECL_CLASS_SCOPE_P (t)
12221 && uses_template_parms (DECL_CONTEXT (t)))
12223 /* Template template argument like the following example need
12226 template <template <class> class TT> struct C {};
12227 template <class T> struct D {
12228 template <class U> struct E {};
12233 We are processing the template argument `E' in #1 for
12234 the template instantiation #2. Originally, `E' is a
12235 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
12236 have to substitute this with one having context `D<int>'. */
12238 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
12239 return lookup_field (context, DECL_NAME(t), 0, false);
12242 /* Ordinary template template argument. */
12246 case REINTERPRET_CAST_EXPR:
12247 case CONST_CAST_EXPR:
12248 case STATIC_CAST_EXPR:
12249 case DYNAMIC_CAST_EXPR:
12250 case IMPLICIT_CONV_EXPR:
12254 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12255 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12258 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12264 ++cp_unevaluated_operand;
12265 ++c_inhibit_evaluation_warnings;
12266 /* We only want to compute the number of arguments. */
12267 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
12268 complain, in_decl);
12269 --cp_unevaluated_operand;
12270 --c_inhibit_evaluation_warnings;
12272 if (TREE_CODE (expanded) == TREE_VEC)
12273 len = TREE_VEC_LENGTH (expanded);
12275 if (expanded == error_mark_node)
12276 return error_mark_node;
12277 else if (PACK_EXPANSION_P (expanded)
12278 || (TREE_CODE (expanded) == TREE_VEC
12280 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
12282 if (TREE_CODE (expanded) == TREE_VEC)
12283 expanded = TREE_VEC_ELT (expanded, len - 1);
12285 if (TYPE_P (expanded))
12286 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
12287 complain & tf_error);
12289 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
12290 complain & tf_error);
12293 return build_int_cst (size_type_node, len);
12299 case TRUTH_NOT_EXPR:
12302 case UNARY_PLUS_EXPR: /* Unary + */
12304 case AT_ENCODE_EXPR:
12308 case REALPART_EXPR:
12309 case IMAGPART_EXPR:
12311 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12312 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12314 case COMPONENT_REF:
12319 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
12320 name = TREE_OPERAND (t, 1);
12321 if (TREE_CODE (name) == BIT_NOT_EXPR)
12323 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12324 complain, in_decl);
12325 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12327 else if (TREE_CODE (name) == SCOPE_REF
12328 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
12330 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
12331 complain, in_decl);
12332 name = TREE_OPERAND (name, 1);
12333 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12334 complain, in_decl);
12335 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12336 name = build_qualified_name (/*type=*/NULL_TREE,
12338 /*template_p=*/false);
12340 else if (BASELINK_P (name))
12341 name = tsubst_baselink (name,
12342 non_reference (TREE_TYPE (object)),
12346 name = tsubst_copy (name, args, complain, in_decl);
12347 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
12353 case TRUNC_DIV_EXPR:
12354 case CEIL_DIV_EXPR:
12355 case FLOOR_DIV_EXPR:
12356 case ROUND_DIV_EXPR:
12357 case EXACT_DIV_EXPR:
12361 case TRUNC_MOD_EXPR:
12362 case FLOOR_MOD_EXPR:
12363 case TRUTH_ANDIF_EXPR:
12364 case TRUTH_ORIF_EXPR:
12365 case TRUTH_AND_EXPR:
12366 case TRUTH_OR_EXPR:
12379 case COMPOUND_EXPR:
12382 case PREDECREMENT_EXPR:
12383 case PREINCREMENT_EXPR:
12384 case POSTDECREMENT_EXPR:
12385 case POSTINCREMENT_EXPR:
12387 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12388 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12391 return build_qualified_name (/*type=*/NULL_TREE,
12392 tsubst_copy (TREE_OPERAND (t, 0),
12393 args, complain, in_decl),
12394 tsubst_copy (TREE_OPERAND (t, 1),
12395 args, complain, in_decl),
12396 QUALIFIED_NAME_IS_TEMPLATE (t));
12401 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12402 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12403 NULL_TREE, NULL_TREE);
12407 int n = VL_EXP_OPERAND_LENGTH (t);
12408 tree result = build_vl_exp (CALL_EXPR, n);
12410 for (i = 0; i < n; i++)
12411 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
12412 complain, in_decl);
12418 case PSEUDO_DTOR_EXPR:
12421 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12422 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12423 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12424 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12431 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12432 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12433 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12434 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
12441 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12442 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12443 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
12444 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
12448 case TEMPLATE_ID_EXPR:
12450 /* Substituted template arguments */
12451 tree fn = TREE_OPERAND (t, 0);
12452 tree targs = TREE_OPERAND (t, 1);
12454 fn = tsubst_copy (fn, args, complain, in_decl);
12456 targs = tsubst_template_args (targs, args, complain, in_decl);
12458 return lookup_template_function (fn, targs);
12463 tree purpose, value, chain;
12465 if (t == void_list_node)
12468 purpose = TREE_PURPOSE (t);
12470 purpose = tsubst_copy (purpose, args, complain, in_decl);
12471 value = TREE_VALUE (t);
12473 value = tsubst_copy (value, args, complain, in_decl);
12474 chain = TREE_CHAIN (t);
12475 if (chain && chain != void_type_node)
12476 chain = tsubst_copy (chain, args, complain, in_decl);
12477 if (purpose == TREE_PURPOSE (t)
12478 && value == TREE_VALUE (t)
12479 && chain == TREE_CHAIN (t))
12481 return tree_cons (purpose, value, chain);
12486 case ENUMERAL_TYPE:
12488 case TEMPLATE_TYPE_PARM:
12489 case TEMPLATE_TEMPLATE_PARM:
12490 case BOUND_TEMPLATE_TEMPLATE_PARM:
12491 case TEMPLATE_PARM_INDEX:
12493 case REFERENCE_TYPE:
12495 case FUNCTION_TYPE:
12498 case TYPENAME_TYPE:
12499 case UNBOUND_CLASS_TEMPLATE:
12501 case DECLTYPE_TYPE:
12503 return tsubst (t, args, complain, in_decl);
12505 case IDENTIFIER_NODE:
12506 if (IDENTIFIER_TYPENAME_P (t))
12508 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12509 return mangle_conv_op_name_for_type (new_type);
12515 /* This is handled by tsubst_copy_and_build. */
12516 gcc_unreachable ();
12519 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
12521 tsubst (TREE_TYPE (t), args, complain, in_decl));
12523 case CLEANUP_POINT_EXPR:
12524 /* We shouldn't have built any of these during initial template
12525 generation. Instead, they should be built during instantiation
12526 in response to the saved STMT_IS_FULL_EXPR_P setting. */
12527 gcc_unreachable ();
12531 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12532 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12533 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12534 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
12535 mark_used (TREE_OPERAND (r, 1));
12538 case EXPR_PACK_EXPANSION:
12539 error ("invalid use of pack expansion expression");
12540 return error_mark_node;
12542 case NONTYPE_ARGUMENT_PACK:
12543 error ("use %<...%> to expand argument pack");
12544 return error_mark_node;
12551 /* Instantiate any typedefs in the type. */
12552 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12553 r = fold_convert (type, t);
12554 gcc_assert (TREE_CODE (r) == code);
12559 /* These can sometimes show up in a partial instantiation, but never
12560 involve template parms. */
12561 gcc_assert (!uses_template_parms (t));
12565 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
12566 gcc_checking_assert (false);
12571 /* Like tsubst_copy, but specifically for OpenMP clauses. */
12574 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
12577 tree new_clauses = NULL, nc, oc;
12579 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
12581 nc = copy_node (oc);
12582 OMP_CLAUSE_CHAIN (nc) = new_clauses;
12585 switch (OMP_CLAUSE_CODE (nc))
12587 case OMP_CLAUSE_LASTPRIVATE:
12588 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
12590 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
12591 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
12592 in_decl, /*integral_constant_expression_p=*/false);
12593 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
12594 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
12597 case OMP_CLAUSE_PRIVATE:
12598 case OMP_CLAUSE_SHARED:
12599 case OMP_CLAUSE_FIRSTPRIVATE:
12600 case OMP_CLAUSE_REDUCTION:
12601 case OMP_CLAUSE_COPYIN:
12602 case OMP_CLAUSE_COPYPRIVATE:
12603 case OMP_CLAUSE_IF:
12604 case OMP_CLAUSE_NUM_THREADS:
12605 case OMP_CLAUSE_SCHEDULE:
12606 case OMP_CLAUSE_COLLAPSE:
12607 case OMP_CLAUSE_FINAL:
12608 OMP_CLAUSE_OPERAND (nc, 0)
12609 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
12610 in_decl, /*integral_constant_expression_p=*/false);
12612 case OMP_CLAUSE_NOWAIT:
12613 case OMP_CLAUSE_ORDERED:
12614 case OMP_CLAUSE_DEFAULT:
12615 case OMP_CLAUSE_UNTIED:
12616 case OMP_CLAUSE_MERGEABLE:
12619 gcc_unreachable ();
12623 return finish_omp_clauses (nreverse (new_clauses));
12626 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
12629 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
12632 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
12634 tree purpose, value, chain;
12639 if (TREE_CODE (t) != TREE_LIST)
12640 return tsubst_copy_and_build (t, args, complain, in_decl,
12641 /*function_p=*/false,
12642 /*integral_constant_expression_p=*/false);
12644 if (t == void_list_node)
12647 purpose = TREE_PURPOSE (t);
12649 purpose = RECUR (purpose);
12650 value = TREE_VALUE (t);
12653 if (TREE_CODE (value) != LABEL_DECL)
12654 value = RECUR (value);
12657 value = lookup_label (DECL_NAME (value));
12658 gcc_assert (TREE_CODE (value) == LABEL_DECL);
12659 TREE_USED (value) = 1;
12662 chain = TREE_CHAIN (t);
12663 if (chain && chain != void_type_node)
12664 chain = RECUR (chain);
12665 return tree_cons (purpose, value, chain);
12669 /* Substitute one OMP_FOR iterator. */
12672 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
12673 tree condv, tree incrv, tree *clauses,
12674 tree args, tsubst_flags_t complain, tree in_decl,
12675 bool integral_constant_expression_p)
12677 #define RECUR(NODE) \
12678 tsubst_expr ((NODE), args, complain, in_decl, \
12679 integral_constant_expression_p)
12680 tree decl, init, cond, incr, auto_node;
12682 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
12683 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
12684 decl = RECUR (TREE_OPERAND (init, 0));
12685 init = TREE_OPERAND (init, 1);
12686 auto_node = type_uses_auto (TREE_TYPE (decl));
12687 if (auto_node && init)
12689 tree init_expr = init;
12690 if (TREE_CODE (init_expr) == DECL_EXPR)
12691 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
12692 init_expr = RECUR (init_expr);
12694 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
12696 gcc_assert (!type_dependent_expression_p (decl));
12698 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
12700 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
12701 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12702 if (TREE_CODE (incr) == MODIFY_EXPR)
12703 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
12704 RECUR (TREE_OPERAND (incr, 1)),
12707 incr = RECUR (incr);
12708 TREE_VEC_ELT (declv, i) = decl;
12709 TREE_VEC_ELT (initv, i) = init;
12710 TREE_VEC_ELT (condv, i) = cond;
12711 TREE_VEC_ELT (incrv, i) = incr;
12715 if (init && TREE_CODE (init) != DECL_EXPR)
12718 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
12720 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
12721 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
12722 && OMP_CLAUSE_DECL (c) == decl)
12724 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
12725 && OMP_CLAUSE_DECL (c) == decl)
12726 error ("iteration variable %qD should not be firstprivate", decl);
12727 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
12728 && OMP_CLAUSE_DECL (c) == decl)
12729 error ("iteration variable %qD should not be reduction", decl);
12733 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
12734 OMP_CLAUSE_DECL (c) = decl;
12735 c = finish_omp_clauses (c);
12738 OMP_CLAUSE_CHAIN (c) = *clauses;
12743 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
12744 if (COMPARISON_CLASS_P (cond))
12745 cond = build2 (TREE_CODE (cond), boolean_type_node,
12746 RECUR (TREE_OPERAND (cond, 0)),
12747 RECUR (TREE_OPERAND (cond, 1)));
12749 cond = RECUR (cond);
12750 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12751 switch (TREE_CODE (incr))
12753 case PREINCREMENT_EXPR:
12754 case PREDECREMENT_EXPR:
12755 case POSTINCREMENT_EXPR:
12756 case POSTDECREMENT_EXPR:
12757 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
12758 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
12761 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12762 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12764 tree rhs = TREE_OPERAND (incr, 1);
12765 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12766 RECUR (TREE_OPERAND (incr, 0)),
12767 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12768 RECUR (TREE_OPERAND (rhs, 0)),
12769 RECUR (TREE_OPERAND (rhs, 1))));
12772 incr = RECUR (incr);
12775 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12776 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12778 tree lhs = RECUR (TREE_OPERAND (incr, 0));
12779 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
12780 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
12781 TREE_TYPE (decl), lhs,
12782 RECUR (TREE_OPERAND (incr, 2))));
12784 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
12785 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
12786 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
12788 tree rhs = TREE_OPERAND (incr, 2);
12789 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12790 RECUR (TREE_OPERAND (incr, 0)),
12791 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12792 RECUR (TREE_OPERAND (rhs, 0)),
12793 RECUR (TREE_OPERAND (rhs, 1))));
12796 incr = RECUR (incr);
12799 incr = RECUR (incr);
12803 TREE_VEC_ELT (declv, i) = decl;
12804 TREE_VEC_ELT (initv, i) = init;
12805 TREE_VEC_ELT (condv, i) = cond;
12806 TREE_VEC_ELT (incrv, i) = incr;
12810 /* Like tsubst_copy for expressions, etc. but also does semantic
12814 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12815 bool integral_constant_expression_p)
12817 #define RECUR(NODE) \
12818 tsubst_expr ((NODE), args, complain, in_decl, \
12819 integral_constant_expression_p)
12823 if (t == NULL_TREE || t == error_mark_node)
12826 if (EXPR_HAS_LOCATION (t))
12827 input_location = EXPR_LOCATION (t);
12828 if (STATEMENT_CODE_P (TREE_CODE (t)))
12829 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12831 switch (TREE_CODE (t))
12833 case STATEMENT_LIST:
12835 tree_stmt_iterator i;
12836 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12837 RECUR (tsi_stmt (i));
12841 case CTOR_INITIALIZER:
12842 finish_mem_initializers (tsubst_initializer_list
12843 (TREE_OPERAND (t, 0), args));
12847 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12851 tmp = RECUR (EXPR_STMT_EXPR (t));
12852 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12853 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12855 finish_expr_stmt (tmp);
12859 do_using_directive (USING_STMT_NAMESPACE (t));
12864 tree decl, pattern_decl;
12867 pattern_decl = decl = DECL_EXPR_DECL (t);
12868 if (TREE_CODE (decl) == LABEL_DECL)
12869 finish_label_decl (DECL_NAME (decl));
12870 else if (TREE_CODE (decl) == USING_DECL)
12872 tree scope = USING_DECL_SCOPE (decl);
12873 tree name = DECL_NAME (decl);
12876 scope = tsubst (scope, args, complain, in_decl);
12877 decl = lookup_qualified_name (scope, name,
12878 /*is_type_p=*/false,
12879 /*complain=*/false);
12880 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12881 qualified_name_lookup_error (scope, name, decl, input_location);
12883 do_local_using_decl (decl, scope, name);
12887 init = DECL_INITIAL (decl);
12888 decl = tsubst (decl, args, complain, in_decl);
12889 if (decl != error_mark_node)
12891 /* By marking the declaration as instantiated, we avoid
12892 trying to instantiate it. Since instantiate_decl can't
12893 handle local variables, and since we've already done
12894 all that needs to be done, that's the right thing to
12896 if (TREE_CODE (decl) == VAR_DECL)
12897 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12898 if (TREE_CODE (decl) == VAR_DECL
12899 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12900 /* Anonymous aggregates are a special case. */
12901 finish_anon_union (decl);
12902 else if (is_capture_proxy (DECL_EXPR_DECL (t)))
12904 DECL_CONTEXT (decl) = current_function_decl;
12905 insert_capture_proxy (decl);
12909 int const_init = false;
12910 maybe_push_decl (decl);
12911 if (TREE_CODE (decl) == VAR_DECL
12912 && DECL_PRETTY_FUNCTION_P (decl))
12914 /* For __PRETTY_FUNCTION__ we have to adjust the
12916 const char *const name
12917 = cxx_printable_name (current_function_decl, 2);
12918 init = cp_fname_init (name, &TREE_TYPE (decl));
12922 tree t = RECUR (init);
12926 /* If we had an initializer but it
12927 instantiated to nothing,
12928 value-initialize the object. This will
12929 only occur when the initializer was a
12930 pack expansion where the parameter packs
12931 used in that expansion were of length
12933 init = build_value_init (TREE_TYPE (decl),
12935 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12936 init = get_target_expr_sfinae (init, complain);
12942 if (TREE_CODE (decl) == VAR_DECL)
12943 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12945 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12950 /* A DECL_EXPR can also be used as an expression, in the condition
12951 clause of an if/for/while construct. */
12956 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12957 RECUR (FOR_INIT_STMT (t));
12958 finish_for_init_stmt (stmt);
12959 tmp = RECUR (FOR_COND (t));
12960 finish_for_cond (tmp, stmt);
12961 tmp = RECUR (FOR_EXPR (t));
12962 finish_for_expr (tmp, stmt);
12963 RECUR (FOR_BODY (t));
12964 finish_for_stmt (stmt);
12967 case RANGE_FOR_STMT:
12970 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12971 decl = RANGE_FOR_DECL (t);
12972 decl = tsubst (decl, args, complain, in_decl);
12973 maybe_push_decl (decl);
12974 expr = RECUR (RANGE_FOR_EXPR (t));
12975 stmt = cp_convert_range_for (stmt, decl, expr);
12976 RECUR (RANGE_FOR_BODY (t));
12977 finish_for_stmt (stmt);
12982 stmt = begin_while_stmt ();
12983 tmp = RECUR (WHILE_COND (t));
12984 finish_while_stmt_cond (tmp, stmt);
12985 RECUR (WHILE_BODY (t));
12986 finish_while_stmt (stmt);
12990 stmt = begin_do_stmt ();
12991 RECUR (DO_BODY (t));
12992 finish_do_body (stmt);
12993 tmp = RECUR (DO_COND (t));
12994 finish_do_stmt (tmp, stmt);
12998 stmt = begin_if_stmt ();
12999 tmp = RECUR (IF_COND (t));
13000 finish_if_stmt_cond (tmp, stmt);
13001 RECUR (THEN_CLAUSE (t));
13002 finish_then_clause (stmt);
13004 if (ELSE_CLAUSE (t))
13006 begin_else_clause (stmt);
13007 RECUR (ELSE_CLAUSE (t));
13008 finish_else_clause (stmt);
13011 finish_if_stmt (stmt);
13015 if (BIND_EXPR_BODY_BLOCK (t))
13016 stmt = begin_function_body ();
13018 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
13019 ? BCS_TRY_BLOCK : 0);
13021 RECUR (BIND_EXPR_BODY (t));
13023 if (BIND_EXPR_BODY_BLOCK (t))
13024 finish_function_body (stmt);
13026 finish_compound_stmt (stmt);
13030 finish_break_stmt ();
13033 case CONTINUE_STMT:
13034 finish_continue_stmt ();
13038 stmt = begin_switch_stmt ();
13039 tmp = RECUR (SWITCH_STMT_COND (t));
13040 finish_switch_cond (tmp, stmt);
13041 RECUR (SWITCH_STMT_BODY (t));
13042 finish_switch_stmt (stmt);
13045 case CASE_LABEL_EXPR:
13046 finish_case_label (EXPR_LOCATION (t),
13047 RECUR (CASE_LOW (t)),
13048 RECUR (CASE_HIGH (t)));
13053 tree decl = LABEL_EXPR_LABEL (t);
13056 label = finish_label_stmt (DECL_NAME (decl));
13057 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
13058 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
13063 tmp = GOTO_DESTINATION (t);
13064 if (TREE_CODE (tmp) != LABEL_DECL)
13065 /* Computed goto's must be tsubst'd into. On the other hand,
13066 non-computed gotos must not be; the identifier in question
13067 will have no binding. */
13070 tmp = DECL_NAME (tmp);
13071 finish_goto_stmt (tmp);
13075 tmp = finish_asm_stmt
13076 (ASM_VOLATILE_P (t),
13077 RECUR (ASM_STRING (t)),
13078 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
13079 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
13080 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
13081 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
13083 tree asm_expr = tmp;
13084 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
13085 asm_expr = TREE_OPERAND (asm_expr, 0);
13086 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
13093 stmt = begin_try_block ();
13094 RECUR (TRY_STMTS (t));
13095 finish_cleanup_try_block (stmt);
13096 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
13100 tree compound_stmt = NULL_TREE;
13102 if (FN_TRY_BLOCK_P (t))
13103 stmt = begin_function_try_block (&compound_stmt);
13105 stmt = begin_try_block ();
13107 RECUR (TRY_STMTS (t));
13109 if (FN_TRY_BLOCK_P (t))
13110 finish_function_try_block (stmt);
13112 finish_try_block (stmt);
13114 RECUR (TRY_HANDLERS (t));
13115 if (FN_TRY_BLOCK_P (t))
13116 finish_function_handler_sequence (stmt, compound_stmt);
13118 finish_handler_sequence (stmt);
13124 tree decl = HANDLER_PARMS (t);
13128 decl = tsubst (decl, args, complain, in_decl);
13129 /* Prevent instantiate_decl from trying to instantiate
13130 this variable. We've already done all that needs to be
13132 if (decl != error_mark_node)
13133 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
13135 stmt = begin_handler ();
13136 finish_handler_parms (decl, stmt);
13137 RECUR (HANDLER_BODY (t));
13138 finish_handler (stmt);
13143 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13146 case STATIC_ASSERT:
13149 tsubst_expr (STATIC_ASSERT_CONDITION (t),
13152 /*integral_constant_expression_p=*/true);
13153 finish_static_assert (condition,
13154 STATIC_ASSERT_MESSAGE (t),
13155 STATIC_ASSERT_SOURCE_LOCATION (t),
13156 /*member_p=*/false);
13161 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
13162 args, complain, in_decl);
13163 stmt = begin_omp_parallel ();
13164 RECUR (OMP_PARALLEL_BODY (t));
13165 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
13166 = OMP_PARALLEL_COMBINED (t);
13170 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
13171 args, complain, in_decl);
13172 stmt = begin_omp_task ();
13173 RECUR (OMP_TASK_BODY (t));
13174 finish_omp_task (tmp, stmt);
13179 tree clauses, body, pre_body;
13180 tree declv, initv, condv, incrv;
13183 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
13184 args, complain, in_decl);
13185 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13186 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13187 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13188 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13190 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
13191 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
13192 &clauses, args, complain, in_decl,
13193 integral_constant_expression_p);
13195 stmt = begin_omp_structured_block ();
13197 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
13198 if (TREE_VEC_ELT (initv, i) == NULL
13199 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
13200 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
13201 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
13203 tree init = RECUR (TREE_VEC_ELT (initv, i));
13204 gcc_assert (init == TREE_VEC_ELT (declv, i));
13205 TREE_VEC_ELT (initv, i) = NULL_TREE;
13209 tree decl_expr = TREE_VEC_ELT (initv, i);
13210 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
13211 gcc_assert (init != NULL);
13212 TREE_VEC_ELT (initv, i) = RECUR (init);
13213 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
13215 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
13218 pre_body = push_stmt_list ();
13219 RECUR (OMP_FOR_PRE_BODY (t));
13220 pre_body = pop_stmt_list (pre_body);
13222 body = push_stmt_list ();
13223 RECUR (OMP_FOR_BODY (t));
13224 body = pop_stmt_list (body);
13226 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
13227 body, pre_body, clauses);
13229 add_stmt (finish_omp_structured_block (stmt));
13235 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
13236 stmt = push_stmt_list ();
13237 RECUR (OMP_BODY (t));
13238 stmt = pop_stmt_list (stmt);
13241 OMP_BODY (t) = stmt;
13242 OMP_CLAUSES (t) = tmp;
13250 stmt = push_stmt_list ();
13251 RECUR (OMP_BODY (t));
13252 stmt = pop_stmt_list (stmt);
13255 OMP_BODY (t) = stmt;
13260 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
13261 if (TREE_CODE (TREE_OPERAND (t, 1)) != MODIFY_EXPR)
13263 tree op1 = TREE_OPERAND (t, 1);
13264 tree rhs1 = NULL_TREE;
13266 if (TREE_CODE (op1) == COMPOUND_EXPR)
13268 rhs1 = RECUR (TREE_OPERAND (op1, 0));
13269 op1 = TREE_OPERAND (op1, 1);
13271 lhs = RECUR (TREE_OPERAND (op1, 0));
13272 rhs = RECUR (TREE_OPERAND (op1, 1));
13273 finish_omp_atomic (OMP_ATOMIC, TREE_CODE (op1), lhs, rhs,
13274 NULL_TREE, NULL_TREE, rhs1);
13278 tree op1 = TREE_OPERAND (t, 1);
13279 tree v = NULL_TREE, lhs, rhs = NULL_TREE, lhs1 = NULL_TREE;
13280 tree rhs1 = NULL_TREE;
13281 enum tree_code code = TREE_CODE (TREE_OPERAND (op1, 1));
13282 enum tree_code opcode = NOP_EXPR;
13283 if (code == OMP_ATOMIC_READ)
13285 v = RECUR (TREE_OPERAND (op1, 0));
13286 lhs = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13288 else if (code == OMP_ATOMIC_CAPTURE_OLD
13289 || code == OMP_ATOMIC_CAPTURE_NEW)
13291 tree op11 = TREE_OPERAND (TREE_OPERAND (op1, 1), 1);
13292 v = RECUR (TREE_OPERAND (op1, 0));
13293 lhs1 = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13294 if (TREE_CODE (op11) == COMPOUND_EXPR)
13296 rhs1 = RECUR (TREE_OPERAND (op11, 0));
13297 op11 = TREE_OPERAND (op11, 1);
13299 lhs = RECUR (TREE_OPERAND (op11, 0));
13300 rhs = RECUR (TREE_OPERAND (op11, 1));
13301 opcode = TREE_CODE (op11);
13306 lhs = RECUR (TREE_OPERAND (op1, 0));
13307 rhs = RECUR (TREE_OPERAND (op1, 1));
13309 finish_omp_atomic (code, opcode, lhs, rhs, v, lhs1, rhs1);
13313 case TRANSACTION_EXPR:
13316 flags |= (TRANSACTION_EXPR_OUTER (t) ? TM_STMT_ATTR_OUTER : 0);
13317 flags |= (TRANSACTION_EXPR_RELAXED (t) ? TM_STMT_ATTR_RELAXED : 0);
13319 if (TRANSACTION_EXPR_IS_STMT (t))
13321 tree body = TRANSACTION_EXPR_BODY (t);
13322 tree noex = NULL_TREE;
13323 if (TREE_CODE (body) == MUST_NOT_THROW_EXPR)
13325 noex = MUST_NOT_THROW_COND (body);
13326 if (noex == NULL_TREE)
13327 noex = boolean_true_node;
13328 body = TREE_OPERAND (body, 0);
13330 stmt = begin_transaction_stmt (input_location, NULL, flags);
13332 finish_transaction_stmt (stmt, NULL, flags, RECUR (noex));
13336 stmt = build_transaction_expr (EXPR_LOCATION (t),
13337 RECUR (TRANSACTION_EXPR_BODY (t)),
13344 case MUST_NOT_THROW_EXPR:
13345 return build_must_not_throw_expr (RECUR (TREE_OPERAND (t, 0)),
13346 RECUR (MUST_NOT_THROW_COND (t)));
13348 case EXPR_PACK_EXPANSION:
13349 error ("invalid use of pack expansion expression");
13350 return error_mark_node;
13352 case NONTYPE_ARGUMENT_PACK:
13353 error ("use %<...%> to expand argument pack");
13354 return error_mark_node;
13357 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
13359 return tsubst_copy_and_build (t, args, complain, in_decl,
13360 /*function_p=*/false,
13361 integral_constant_expression_p);
13368 /* T is a postfix-expression that is not being used in a function
13369 call. Return the substituted version of T. */
13372 tsubst_non_call_postfix_expression (tree t, tree args,
13373 tsubst_flags_t complain,
13376 if (TREE_CODE (t) == SCOPE_REF)
13377 t = tsubst_qualified_id (t, args, complain, in_decl,
13378 /*done=*/false, /*address_p=*/false);
13380 t = tsubst_copy_and_build (t, args, complain, in_decl,
13381 /*function_p=*/false,
13382 /*integral_constant_expression_p=*/false);
13387 /* Like tsubst but deals with expressions and performs semantic
13388 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
13391 tsubst_copy_and_build (tree t,
13393 tsubst_flags_t complain,
13396 bool integral_constant_expression_p)
13398 #define RECUR(NODE) \
13399 tsubst_copy_and_build (NODE, args, complain, in_decl, \
13400 /*function_p=*/false, \
13401 integral_constant_expression_p)
13405 if (t == NULL_TREE || t == error_mark_node)
13408 switch (TREE_CODE (t))
13412 /* Fall through. */
13413 case IDENTIFIER_NODE:
13417 bool non_integral_constant_expression_p;
13418 const char *error_msg;
13420 if (IDENTIFIER_TYPENAME_P (t))
13422 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13423 t = mangle_conv_op_name_for_type (new_type);
13426 /* Look up the name. */
13427 decl = lookup_name (t);
13429 /* By convention, expressions use ERROR_MARK_NODE to indicate
13430 failure, not NULL_TREE. */
13431 if (decl == NULL_TREE)
13432 decl = error_mark_node;
13434 decl = finish_id_expression (t, decl, NULL_TREE,
13436 integral_constant_expression_p,
13437 /*allow_non_integral_constant_expression_p=*/(cxx_dialect >= cxx0x),
13438 &non_integral_constant_expression_p,
13439 /*template_p=*/false,
13441 /*address_p=*/false,
13442 /*template_arg_p=*/false,
13447 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
13449 if (complain & tf_error)
13450 unqualified_name_lookup_error (decl);
13451 decl = error_mark_node;
13456 case TEMPLATE_ID_EXPR:
13459 tree templ = RECUR (TREE_OPERAND (t, 0));
13460 tree targs = TREE_OPERAND (t, 1);
13463 targs = tsubst_template_args (targs, args, complain, in_decl);
13465 if (TREE_CODE (templ) == COMPONENT_REF)
13467 object = TREE_OPERAND (templ, 0);
13468 templ = TREE_OPERAND (templ, 1);
13471 object = NULL_TREE;
13472 templ = lookup_template_function (templ, targs);
13475 return build3 (COMPONENT_REF, TREE_TYPE (templ),
13476 object, templ, NULL_TREE);
13478 return baselink_for_fns (templ);
13483 tree r = RECUR (TREE_OPERAND (t, 0));
13485 if (REFERENCE_REF_P (t))
13487 /* A type conversion to reference type will be enclosed in
13488 such an indirect ref, but the substitution of the cast
13489 will have also added such an indirect ref. */
13490 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
13491 r = convert_from_reference (r);
13494 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain);
13500 (tsubst (TREE_TYPE (t), args, complain, in_decl),
13501 RECUR (TREE_OPERAND (t, 0)));
13503 case IMPLICIT_CONV_EXPR:
13505 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13506 tree expr = RECUR (TREE_OPERAND (t, 0));
13507 int flags = LOOKUP_IMPLICIT;
13508 if (IMPLICIT_CONV_EXPR_DIRECT_INIT (t))
13509 flags = LOOKUP_NORMAL;
13510 return perform_implicit_conversion_flags (type, expr, complain,
13517 tsubst (TREE_TYPE (t), args, complain, in_decl),
13518 RECUR (TREE_OPERAND (t, 0)));
13521 case REINTERPRET_CAST_EXPR:
13522 case CONST_CAST_EXPR:
13523 case DYNAMIC_CAST_EXPR:
13524 case STATIC_CAST_EXPR:
13529 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13530 if (integral_constant_expression_p
13531 && !cast_valid_in_integral_constant_expression_p (type))
13533 if (complain & tf_error)
13534 error ("a cast to a type other than an integral or "
13535 "enumeration type cannot appear in a constant-expression");
13536 return error_mark_node;
13539 op = RECUR (TREE_OPERAND (t, 0));
13541 switch (TREE_CODE (t))
13544 return build_functional_cast (type, op, complain);
13545 case REINTERPRET_CAST_EXPR:
13546 return build_reinterpret_cast (type, op, complain);
13547 case CONST_CAST_EXPR:
13548 return build_const_cast (type, op, complain);
13549 case DYNAMIC_CAST_EXPR:
13550 return build_dynamic_cast (type, op, complain);
13551 case STATIC_CAST_EXPR:
13552 return build_static_cast (type, op, complain);
13554 gcc_unreachable ();
13558 case POSTDECREMENT_EXPR:
13559 case POSTINCREMENT_EXPR:
13560 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13561 args, complain, in_decl);
13562 return build_x_unary_op (TREE_CODE (t), op1, complain);
13564 case PREDECREMENT_EXPR:
13565 case PREINCREMENT_EXPR:
13569 case TRUTH_NOT_EXPR:
13570 case UNARY_PLUS_EXPR: /* Unary + */
13571 case REALPART_EXPR:
13572 case IMAGPART_EXPR:
13573 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
13576 case FIX_TRUNC_EXPR:
13577 return cp_build_unary_op (FIX_TRUNC_EXPR, RECUR (TREE_OPERAND (t, 0)),
13581 op1 = TREE_OPERAND (t, 0);
13582 if (TREE_CODE (op1) == LABEL_DECL)
13583 return finish_label_address_expr (DECL_NAME (op1),
13584 EXPR_LOCATION (op1));
13585 if (TREE_CODE (op1) == SCOPE_REF)
13586 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
13587 /*done=*/true, /*address_p=*/true);
13589 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
13591 return build_x_unary_op (ADDR_EXPR, op1, complain);
13596 case TRUNC_DIV_EXPR:
13597 case CEIL_DIV_EXPR:
13598 case FLOOR_DIV_EXPR:
13599 case ROUND_DIV_EXPR:
13600 case EXACT_DIV_EXPR:
13604 case TRUNC_MOD_EXPR:
13605 case FLOOR_MOD_EXPR:
13606 case TRUTH_ANDIF_EXPR:
13607 case TRUTH_ORIF_EXPR:
13608 case TRUTH_AND_EXPR:
13609 case TRUTH_OR_EXPR:
13625 tree r = build_x_binary_op
13627 RECUR (TREE_OPERAND (t, 0)),
13628 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
13630 : TREE_CODE (TREE_OPERAND (t, 0))),
13631 RECUR (TREE_OPERAND (t, 1)),
13632 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
13634 : TREE_CODE (TREE_OPERAND (t, 1))),
13637 if (EXPR_P (r) && TREE_NO_WARNING (t))
13638 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13643 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
13644 /*address_p=*/false);
13646 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13647 args, complain, in_decl);
13648 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
13651 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
13652 return tsubst_copy (t, args, complain, in_decl);
13656 op1 = TREE_OPERAND (t, 0);
13659 /* When there are no ARGS, we are trying to evaluate a
13660 non-dependent expression from the parser. Trying to do
13661 the substitutions may not work. */
13663 op1 = TREE_TYPE (op1);
13667 ++cp_unevaluated_operand;
13668 ++c_inhibit_evaluation_warnings;
13669 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13670 /*function_p=*/false,
13671 /*integral_constant_expression_p=*/false);
13672 --cp_unevaluated_operand;
13673 --c_inhibit_evaluation_warnings;
13676 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
13677 complain & tf_error);
13679 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
13680 complain & tf_error);
13682 case AT_ENCODE_EXPR:
13684 op1 = TREE_OPERAND (t, 0);
13685 ++cp_unevaluated_operand;
13686 ++c_inhibit_evaluation_warnings;
13687 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13688 /*function_p=*/false,
13689 /*integral_constant_expression_p=*/false);
13690 --cp_unevaluated_operand;
13691 --c_inhibit_evaluation_warnings;
13692 return objc_build_encode_expr (op1);
13695 case NOEXCEPT_EXPR:
13696 op1 = TREE_OPERAND (t, 0);
13697 ++cp_unevaluated_operand;
13698 ++c_inhibit_evaluation_warnings;
13699 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13700 /*function_p=*/false,
13701 /*integral_constant_expression_p=*/false);
13702 --cp_unevaluated_operand;
13703 --c_inhibit_evaluation_warnings;
13704 return finish_noexcept_expr (op1, complain);
13708 tree r = build_x_modify_expr
13709 (RECUR (TREE_OPERAND (t, 0)),
13710 TREE_CODE (TREE_OPERAND (t, 1)),
13711 RECUR (TREE_OPERAND (t, 2)),
13713 /* TREE_NO_WARNING must be set if either the expression was
13714 parenthesized or it uses an operator such as >>= rather
13715 than plain assignment. In the former case, it was already
13716 set and must be copied. In the latter case,
13717 build_x_modify_expr sets it and it must not be reset
13719 if (TREE_NO_WARNING (t))
13720 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13725 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13726 args, complain, in_decl);
13727 /* Remember that there was a reference to this entity. */
13730 return build_x_arrow (op1);
13734 tree placement = RECUR (TREE_OPERAND (t, 0));
13735 tree init = RECUR (TREE_OPERAND (t, 3));
13736 VEC(tree,gc) *placement_vec;
13737 VEC(tree,gc) *init_vec;
13740 if (placement == NULL_TREE)
13741 placement_vec = NULL;
13744 placement_vec = make_tree_vector ();
13745 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
13746 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
13749 /* If there was an initializer in the original tree, but it
13750 instantiated to an empty list, then we should pass a
13751 non-NULL empty vector to tell build_new that it was an
13752 empty initializer() rather than no initializer. This can
13753 only happen when the initializer is a pack expansion whose
13754 parameter packs are of length zero. */
13755 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
13759 init_vec = make_tree_vector ();
13760 if (init == void_zero_node)
13761 gcc_assert (init_vec != NULL);
13764 for (; init != NULL_TREE; init = TREE_CHAIN (init))
13765 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
13769 ret = build_new (&placement_vec,
13770 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
13771 RECUR (TREE_OPERAND (t, 2)),
13773 NEW_EXPR_USE_GLOBAL (t),
13776 if (placement_vec != NULL)
13777 release_tree_vector (placement_vec);
13778 if (init_vec != NULL)
13779 release_tree_vector (init_vec);
13785 return delete_sanity
13786 (RECUR (TREE_OPERAND (t, 0)),
13787 RECUR (TREE_OPERAND (t, 1)),
13788 DELETE_EXPR_USE_VEC (t),
13789 DELETE_EXPR_USE_GLOBAL (t),
13792 case COMPOUND_EXPR:
13793 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
13794 RECUR (TREE_OPERAND (t, 1)),
13800 VEC(tree,gc) *call_args;
13801 unsigned int nargs, i;
13806 function = CALL_EXPR_FN (t);
13807 /* When we parsed the expression, we determined whether or
13808 not Koenig lookup should be performed. */
13809 koenig_p = KOENIG_LOOKUP_P (t);
13810 if (TREE_CODE (function) == SCOPE_REF)
13812 qualified_p = true;
13813 function = tsubst_qualified_id (function, args, complain, in_decl,
13815 /*address_p=*/false);
13817 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE)
13819 /* Do nothing; calling tsubst_copy_and_build on an identifier
13820 would incorrectly perform unqualified lookup again.
13822 Note that we can also have an IDENTIFIER_NODE if the earlier
13823 unqualified lookup found a member function; in that case
13824 koenig_p will be false and we do want to do the lookup
13825 again to find the instantiated member function.
13827 FIXME but doing that causes c++/15272, so we need to stop
13828 using IDENTIFIER_NODE in that situation. */
13829 qualified_p = false;
13833 if (TREE_CODE (function) == COMPONENT_REF)
13835 tree op = TREE_OPERAND (function, 1);
13837 qualified_p = (TREE_CODE (op) == SCOPE_REF
13838 || (BASELINK_P (op)
13839 && BASELINK_QUALIFIED_P (op)));
13842 qualified_p = false;
13844 function = tsubst_copy_and_build (function, args, complain,
13847 integral_constant_expression_p);
13849 if (BASELINK_P (function))
13850 qualified_p = true;
13853 nargs = call_expr_nargs (t);
13854 call_args = make_tree_vector ();
13855 for (i = 0; i < nargs; ++i)
13857 tree arg = CALL_EXPR_ARG (t, i);
13859 if (!PACK_EXPANSION_P (arg))
13860 VEC_safe_push (tree, gc, call_args,
13861 RECUR (CALL_EXPR_ARG (t, i)));
13864 /* Expand the pack expansion and push each entry onto
13866 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
13867 if (TREE_CODE (arg) == TREE_VEC)
13869 unsigned int len, j;
13871 len = TREE_VEC_LENGTH (arg);
13872 for (j = 0; j < len; ++j)
13874 tree value = TREE_VEC_ELT (arg, j);
13875 if (value != NULL_TREE)
13876 value = convert_from_reference (value);
13877 VEC_safe_push (tree, gc, call_args, value);
13882 /* A partial substitution. Add one entry. */
13883 VEC_safe_push (tree, gc, call_args, arg);
13888 /* We do not perform argument-dependent lookup if normal
13889 lookup finds a non-function, in accordance with the
13890 expected resolution of DR 218. */
13892 && ((is_overloaded_fn (function)
13893 /* If lookup found a member function, the Koenig lookup is
13894 not appropriate, even if an unqualified-name was used
13895 to denote the function. */
13896 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
13897 || TREE_CODE (function) == IDENTIFIER_NODE)
13898 /* Only do this when substitution turns a dependent call
13899 into a non-dependent call. */
13900 && type_dependent_expression_p_push (t)
13901 && !any_type_dependent_arguments_p (call_args))
13902 function = perform_koenig_lookup (function, call_args, false,
13905 if (TREE_CODE (function) == IDENTIFIER_NODE
13906 && !any_type_dependent_arguments_p (call_args))
13908 if (koenig_p && (complain & tf_warning_or_error))
13910 /* For backwards compatibility and good diagnostics, try
13911 the unqualified lookup again if we aren't in SFINAE
13913 tree unq = (tsubst_copy_and_build
13914 (function, args, complain, in_decl, true,
13915 integral_constant_expression_p));
13916 if (unq == error_mark_node)
13917 return error_mark_node;
13919 if (unq != function)
13922 if (TREE_CODE (fn) == INDIRECT_REF)
13923 fn = TREE_OPERAND (fn, 0);
13924 if (TREE_CODE (fn) == COMPONENT_REF)
13925 fn = TREE_OPERAND (fn, 1);
13926 if (is_overloaded_fn (fn))
13927 fn = get_first_fn (fn);
13928 permerror (EXPR_LOC_OR_HERE (t),
13929 "%qD was not declared in this scope, "
13930 "and no declarations were found by "
13931 "argument-dependent lookup at the point "
13932 "of instantiation", function);
13934 /* Can't say anything more. */;
13935 else if (DECL_CLASS_SCOPE_P (fn))
13937 inform (EXPR_LOC_OR_HERE (t),
13938 "declarations in dependent base %qT are "
13939 "not found by unqualified lookup",
13940 DECL_CLASS_CONTEXT (fn));
13941 if (current_class_ptr)
13942 inform (EXPR_LOC_OR_HERE (t),
13943 "use %<this->%D%> instead", function);
13945 inform (EXPR_LOC_OR_HERE (t),
13946 "use %<%T::%D%> instead",
13947 current_class_name, function);
13950 inform (0, "%q+D declared here, later in the "
13951 "translation unit", fn);
13955 if (TREE_CODE (function) == IDENTIFIER_NODE)
13957 unqualified_name_lookup_error (function);
13958 release_tree_vector (call_args);
13959 return error_mark_node;
13963 /* Remember that there was a reference to this entity. */
13964 if (DECL_P (function))
13965 mark_used (function);
13967 if (TREE_CODE (function) == OFFSET_REF)
13968 ret = build_offset_ref_call_from_tree (function, &call_args);
13969 else if (TREE_CODE (function) == COMPONENT_REF)
13971 tree instance = TREE_OPERAND (function, 0);
13972 tree fn = TREE_OPERAND (function, 1);
13974 if (processing_template_decl
13975 && (type_dependent_expression_p (instance)
13976 || (!BASELINK_P (fn)
13977 && TREE_CODE (fn) != FIELD_DECL)
13978 || type_dependent_expression_p (fn)
13979 || any_type_dependent_arguments_p (call_args)))
13980 ret = build_nt_call_vec (function, call_args);
13981 else if (!BASELINK_P (fn))
13982 ret = finish_call_expr (function, &call_args,
13983 /*disallow_virtual=*/false,
13984 /*koenig_p=*/false,
13987 ret = (build_new_method_call
13989 &call_args, NULL_TREE,
13990 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
13995 ret = finish_call_expr (function, &call_args,
13996 /*disallow_virtual=*/qualified_p,
14000 release_tree_vector (call_args);
14006 return build_x_conditional_expr
14007 (RECUR (TREE_OPERAND (t, 0)),
14008 RECUR (TREE_OPERAND (t, 1)),
14009 RECUR (TREE_OPERAND (t, 2)),
14012 case PSEUDO_DTOR_EXPR:
14013 return finish_pseudo_destructor_expr
14014 (RECUR (TREE_OPERAND (t, 0)),
14015 RECUR (TREE_OPERAND (t, 1)),
14016 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl));
14020 tree purpose, value, chain;
14022 if (t == void_list_node)
14025 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
14026 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
14028 /* We have pack expansions, so expand those and
14029 create a new list out of it. */
14030 tree purposevec = NULL_TREE;
14031 tree valuevec = NULL_TREE;
14035 /* Expand the argument expressions. */
14036 if (TREE_PURPOSE (t))
14037 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
14038 complain, in_decl);
14039 if (TREE_VALUE (t))
14040 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
14041 complain, in_decl);
14043 /* Build the rest of the list. */
14044 chain = TREE_CHAIN (t);
14045 if (chain && chain != void_type_node)
14046 chain = RECUR (chain);
14048 /* Determine the number of arguments. */
14049 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
14051 len = TREE_VEC_LENGTH (purposevec);
14052 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
14054 else if (TREE_CODE (valuevec) == TREE_VEC)
14055 len = TREE_VEC_LENGTH (valuevec);
14058 /* Since we only performed a partial substitution into
14059 the argument pack, we only return a single list
14061 if (purposevec == TREE_PURPOSE (t)
14062 && valuevec == TREE_VALUE (t)
14063 && chain == TREE_CHAIN (t))
14066 return tree_cons (purposevec, valuevec, chain);
14069 /* Convert the argument vectors into a TREE_LIST */
14073 /* Grab the Ith values. */
14075 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
14078 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
14081 /* Build the list (backwards). */
14082 chain = tree_cons (purpose, value, chain);
14088 purpose = TREE_PURPOSE (t);
14090 purpose = RECUR (purpose);
14091 value = TREE_VALUE (t);
14093 value = RECUR (value);
14094 chain = TREE_CHAIN (t);
14095 if (chain && chain != void_type_node)
14096 chain = RECUR (chain);
14097 if (purpose == TREE_PURPOSE (t)
14098 && value == TREE_VALUE (t)
14099 && chain == TREE_CHAIN (t))
14101 return tree_cons (purpose, value, chain);
14104 case COMPONENT_REF:
14110 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
14111 args, complain, in_decl);
14112 /* Remember that there was a reference to this entity. */
14113 if (DECL_P (object))
14114 mark_used (object);
14115 object_type = TREE_TYPE (object);
14117 member = TREE_OPERAND (t, 1);
14118 if (BASELINK_P (member))
14119 member = tsubst_baselink (member,
14120 non_reference (TREE_TYPE (object)),
14121 args, complain, in_decl);
14123 member = tsubst_copy (member, args, complain, in_decl);
14124 if (member == error_mark_node)
14125 return error_mark_node;
14127 if (type_dependent_expression_p (object))
14128 /* We can't do much here. */;
14129 else if (!CLASS_TYPE_P (object_type))
14131 if (SCALAR_TYPE_P (object_type))
14133 tree s = NULL_TREE;
14134 tree dtor = member;
14136 if (TREE_CODE (dtor) == SCOPE_REF)
14138 s = TREE_OPERAND (dtor, 0);
14139 dtor = TREE_OPERAND (dtor, 1);
14141 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
14143 dtor = TREE_OPERAND (dtor, 0);
14145 return finish_pseudo_destructor_expr (object, s, dtor);
14149 else if (TREE_CODE (member) == SCOPE_REF
14150 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
14152 /* Lookup the template functions now that we know what the
14154 tree scope = TREE_OPERAND (member, 0);
14155 tree tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
14156 tree args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
14157 member = lookup_qualified_name (scope, tmpl,
14158 /*is_type_p=*/false,
14159 /*complain=*/false);
14160 if (BASELINK_P (member))
14162 BASELINK_FUNCTIONS (member)
14163 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
14165 member = (adjust_result_of_qualified_name_lookup
14166 (member, BINFO_TYPE (BASELINK_BINFO (member)),
14171 qualified_name_lookup_error (scope, tmpl, member,
14173 return error_mark_node;
14176 else if (TREE_CODE (member) == SCOPE_REF
14177 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
14178 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
14180 if (complain & tf_error)
14182 if (TYPE_P (TREE_OPERAND (member, 0)))
14183 error ("%qT is not a class or namespace",
14184 TREE_OPERAND (member, 0));
14186 error ("%qD is not a class or namespace",
14187 TREE_OPERAND (member, 0));
14189 return error_mark_node;
14191 else if (TREE_CODE (member) == FIELD_DECL)
14192 return finish_non_static_data_member (member, object, NULL_TREE);
14194 return finish_class_member_access_expr (object, member,
14195 /*template_p=*/false,
14201 (RECUR (TREE_OPERAND (t, 0)));
14205 VEC(constructor_elt,gc) *n;
14206 constructor_elt *ce;
14207 unsigned HOST_WIDE_INT idx;
14208 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
14209 bool process_index_p;
14211 bool need_copy_p = false;
14214 if (type == error_mark_node)
14215 return error_mark_node;
14217 /* digest_init will do the wrong thing if we let it. */
14218 if (type && TYPE_PTRMEMFUNC_P (type))
14221 /* We do not want to process the index of aggregate
14222 initializers as they are identifier nodes which will be
14223 looked up by digest_init. */
14224 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
14226 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
14227 newlen = VEC_length (constructor_elt, n);
14228 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce)
14230 if (ce->index && process_index_p)
14231 ce->index = RECUR (ce->index);
14233 if (PACK_EXPANSION_P (ce->value))
14235 /* Substitute into the pack expansion. */
14236 ce->value = tsubst_pack_expansion (ce->value, args, complain,
14239 if (ce->value == error_mark_node
14240 || PACK_EXPANSION_P (ce->value))
14242 else if (TREE_VEC_LENGTH (ce->value) == 1)
14243 /* Just move the argument into place. */
14244 ce->value = TREE_VEC_ELT (ce->value, 0);
14247 /* Update the length of the final CONSTRUCTOR
14248 arguments vector, and note that we will need to
14250 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
14251 need_copy_p = true;
14255 ce->value = RECUR (ce->value);
14260 VEC(constructor_elt,gc) *old_n = n;
14262 n = VEC_alloc (constructor_elt, gc, newlen);
14263 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce)
14265 if (TREE_CODE (ce->value) == TREE_VEC)
14267 int i, len = TREE_VEC_LENGTH (ce->value);
14268 for (i = 0; i < len; ++i)
14269 CONSTRUCTOR_APPEND_ELT (n, 0,
14270 TREE_VEC_ELT (ce->value, i));
14273 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
14277 r = build_constructor (init_list_type_node, n);
14278 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
14280 if (TREE_HAS_CONSTRUCTOR (t))
14281 return finish_compound_literal (type, r, complain);
14283 TREE_TYPE (r) = type;
14289 tree operand_0 = TREE_OPERAND (t, 0);
14290 if (TYPE_P (operand_0))
14292 operand_0 = tsubst (operand_0, args, complain, in_decl);
14293 return get_typeid (operand_0);
14297 operand_0 = RECUR (operand_0);
14298 return build_typeid (operand_0);
14309 tree r = tsubst_copy (t, args, complain, in_decl);
14311 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
14312 /* If the original type was a reference, we'll be wrapped in
14313 the appropriate INDIRECT_REF. */
14314 r = convert_from_reference (r);
14319 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
14320 tsubst (TREE_TYPE (t), args, complain, in_decl));
14322 case OFFSETOF_EXPR:
14323 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
14327 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
14328 complain, in_decl);
14330 tree type2 = TRAIT_EXPR_TYPE2 (t);
14332 type2 = tsubst_copy (type2, args, complain, in_decl);
14334 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
14339 tree old_stmt_expr = cur_stmt_expr;
14340 tree stmt_expr = begin_stmt_expr ();
14342 cur_stmt_expr = stmt_expr;
14343 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
14344 integral_constant_expression_p);
14345 stmt_expr = finish_stmt_expr (stmt_expr, false);
14346 cur_stmt_expr = old_stmt_expr;
14348 /* If the resulting list of expression statement is empty,
14349 fold it further into void_zero_node. */
14350 if (empty_expr_stmt_p (stmt_expr))
14351 stmt_expr = void_zero_node;
14357 t = tsubst_copy (t, args, complain, in_decl);
14358 /* As in finish_id_expression, we resolve enumeration constants
14359 to their underlying values. */
14360 if (TREE_CODE (t) == CONST_DECL && !processing_template_decl)
14362 used_types_insert (TREE_TYPE (t));
14363 return DECL_INITIAL (t);
14369 tree r = build_lambda_expr ();
14371 tree type = tsubst (LAMBDA_EXPR_CLOSURE (t), args, complain, NULL_TREE);
14372 LAMBDA_EXPR_CLOSURE (r) = type;
14373 CLASSTYPE_LAMBDA_EXPR (type) = r;
14375 LAMBDA_EXPR_LOCATION (r)
14376 = LAMBDA_EXPR_LOCATION (t);
14377 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
14378 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
14379 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
14380 LAMBDA_EXPR_DISCRIMINATOR (r)
14381 = (LAMBDA_EXPR_DISCRIMINATOR (t));
14382 LAMBDA_EXPR_EXTRA_SCOPE (r)
14383 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
14384 if (LAMBDA_EXPR_RETURN_TYPE (t) == dependent_lambda_return_type_node)
14386 LAMBDA_EXPR_RETURN_TYPE (r) = dependent_lambda_return_type_node;
14387 LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (r) = true;
14390 LAMBDA_EXPR_RETURN_TYPE (r)
14391 = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
14393 gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (t) == NULL_TREE
14394 && LAMBDA_EXPR_PENDING_PROXIES (t) == NULL);
14396 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
14397 determine_visibility (TYPE_NAME (type));
14398 /* Now that we know visibility, instantiate the type so we have a
14399 declaration of the op() for later calls to lambda_function. */
14400 complete_type (type);
14402 /* The capture list refers to closure members, so this needs to
14403 wait until after we finish instantiating the type. */
14404 LAMBDA_EXPR_CAPTURE_LIST (r)
14405 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
14407 return build_lambda_object (r);
14411 /* We can get here for a constant initializer of non-dependent type.
14412 FIXME stop folding in cp_parser_initializer_clause. */
14413 gcc_assert (TREE_CONSTANT (t));
14415 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t)));
14416 TREE_CONSTANT (r) = true;
14420 case TRANSACTION_EXPR:
14421 return tsubst_expr(t, args, complain, in_decl,
14422 integral_constant_expression_p);
14425 /* Handle Objective-C++ constructs, if appropriate. */
14428 = objcp_tsubst_copy_and_build (t, args, complain,
14429 in_decl, /*function_p=*/false);
14433 return tsubst_copy (t, args, complain, in_decl);
14439 /* Verify that the instantiated ARGS are valid. For type arguments,
14440 make sure that the type's linkage is ok. For non-type arguments,
14441 make sure they are constants if they are integral or enumerations.
14442 Emit an error under control of COMPLAIN, and return TRUE on error. */
14445 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
14447 if (ARGUMENT_PACK_P (t))
14449 tree vec = ARGUMENT_PACK_ARGS (t);
14450 int len = TREE_VEC_LENGTH (vec);
14451 bool result = false;
14454 for (i = 0; i < len; ++i)
14455 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
14459 else if (TYPE_P (t))
14461 /* [basic.link]: A name with no linkage (notably, the name
14462 of a class or enumeration declared in a local scope)
14463 shall not be used to declare an entity with linkage.
14464 This implies that names with no linkage cannot be used as
14467 DR 757 relaxes this restriction for C++0x. */
14468 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
14469 : no_linkage_check (t, /*relaxed_p=*/false));
14473 /* DR 488 makes use of a type with no linkage cause
14474 type deduction to fail. */
14475 if (complain & tf_error)
14477 if (TYPE_ANONYMOUS_P (nt))
14478 error ("%qT is/uses anonymous type", t);
14480 error ("template argument for %qD uses local type %qT",
14485 /* In order to avoid all sorts of complications, we do not
14486 allow variably-modified types as template arguments. */
14487 else if (variably_modified_type_p (t, NULL_TREE))
14489 if (complain & tf_error)
14490 error ("%qT is a variably modified type", t);
14494 /* A non-type argument of integral or enumerated type must be a
14496 else if (TREE_TYPE (t)
14497 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
14498 && !TREE_CONSTANT (t))
14500 if (complain & tf_error)
14501 error ("integral expression %qE is not constant", t);
14508 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
14510 int ix, len = DECL_NTPARMS (tmpl);
14511 bool result = false;
14513 for (ix = 0; ix != len; ix++)
14515 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
14518 if (result && (complain & tf_error))
14519 error (" trying to instantiate %qD", tmpl);
14523 /* In C++0x, it's possible to have a function template whose type depends
14524 on itself recursively. This is most obvious with decltype, but can also
14525 occur with enumeration scope (c++/48969). So we need to catch infinite
14526 recursion and reject the substitution at deduction time; this function
14527 will return error_mark_node for any repeated substitution.
14529 This also catches excessive recursion such as when f<N> depends on
14530 f<N-1> across all integers, and returns error_mark_node for all the
14531 substitutions back up to the initial one.
14533 This is, of course, not reentrant. */
14536 deduction_tsubst_fntype (tree fn, tree targs, tsubst_flags_t complain)
14538 static bool excessive_deduction_depth;
14539 static int deduction_depth;
14540 struct pending_template *old_last_pend = last_pending_template;
14541 struct tinst_level *old_error_tinst = last_error_tinst_level;
14543 tree fntype = TREE_TYPE (fn);
14547 if (excessive_deduction_depth)
14548 return error_mark_node;
14550 tinst = build_tree_list (fn, targs);
14551 if (!push_tinst_level (tinst))
14553 excessive_deduction_depth = true;
14555 return error_mark_node;
14558 input_location = DECL_SOURCE_LOCATION (fn);
14560 push_deduction_access_scope (fn);
14561 r = tsubst (fntype, targs, complain, NULL_TREE);
14562 pop_deduction_access_scope (fn);
14565 if (excessive_deduction_depth)
14567 r = error_mark_node;
14568 if (deduction_depth == 0)
14569 /* Reset once we're all the way out. */
14570 excessive_deduction_depth = false;
14573 pop_tinst_level ();
14574 /* We can't free this if a pending_template entry or last_error_tinst_level
14575 is pointing at it. */
14576 if (last_pending_template == old_last_pend
14577 && last_error_tinst_level == old_error_tinst)
14582 /* Instantiate the indicated variable or function template TMPL with
14583 the template arguments in TARG_PTR. */
14586 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
14588 tree targ_ptr = orig_args;
14593 if (tmpl == error_mark_node)
14594 return error_mark_node;
14596 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
14598 /* If this function is a clone, handle it specially. */
14599 if (DECL_CLONED_FUNCTION_P (tmpl))
14604 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
14605 DECL_CLONED_FUNCTION. */
14606 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
14607 targ_ptr, complain);
14608 if (spec == error_mark_node)
14609 return error_mark_node;
14611 /* Look for the clone. */
14612 FOR_EACH_CLONE (clone, spec)
14613 if (DECL_NAME (clone) == DECL_NAME (tmpl))
14615 /* We should always have found the clone by now. */
14616 gcc_unreachable ();
14620 /* Check to see if we already have this specialization. */
14621 gen_tmpl = most_general_template (tmpl);
14622 if (tmpl != gen_tmpl)
14623 /* The TMPL is a partial instantiation. To get a full set of
14624 arguments we must add the arguments used to perform the
14625 partial instantiation. */
14626 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
14629 /* It would be nice to avoid hashing here and then again in tsubst_decl,
14630 but it doesn't seem to be on the hot path. */
14631 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
14633 gcc_assert (tmpl == gen_tmpl
14634 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
14636 || fndecl == NULL_TREE);
14638 if (spec != NULL_TREE)
14641 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
14643 return error_mark_node;
14645 /* We are building a FUNCTION_DECL, during which the access of its
14646 parameters and return types have to be checked. However this
14647 FUNCTION_DECL which is the desired context for access checking
14648 is not built yet. We solve this chicken-and-egg problem by
14649 deferring all checks until we have the FUNCTION_DECL. */
14650 push_deferring_access_checks (dk_deferred);
14652 /* Instantiation of the function happens in the context of the function
14653 template, not the context of the overload resolution we're doing. */
14654 push_to_top_level ();
14655 if (DECL_CLASS_SCOPE_P (gen_tmpl))
14657 tree ctx = tsubst (DECL_CONTEXT (gen_tmpl), targ_ptr,
14658 complain, gen_tmpl);
14659 push_nested_class (ctx);
14661 /* Substitute template parameters to obtain the specialization. */
14662 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
14663 targ_ptr, complain, gen_tmpl);
14664 if (DECL_CLASS_SCOPE_P (gen_tmpl))
14665 pop_nested_class ();
14666 pop_from_top_level ();
14668 if (fndecl == error_mark_node)
14669 return error_mark_node;
14671 /* Now we know the specialization, compute access previously
14673 push_access_scope (fndecl);
14675 /* Some typedefs referenced from within the template code need to be access
14676 checked at template instantiation time, i.e now. These types were
14677 added to the template at parsing time. Let's get those and perfom
14678 the acces checks then. */
14679 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
14680 perform_deferred_access_checks ();
14681 pop_access_scope (fndecl);
14682 pop_deferring_access_checks ();
14684 /* The DECL_TI_TEMPLATE should always be the immediate parent
14685 template, not the most general template. */
14686 DECL_TI_TEMPLATE (fndecl) = tmpl;
14688 /* If we've just instantiated the main entry point for a function,
14689 instantiate all the alternate entry points as well. We do this
14690 by cloning the instantiation of the main entry point, not by
14691 instantiating the template clones. */
14692 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
14693 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
14698 /* Wrapper for instantiate_template_1. */
14701 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
14704 timevar_push (TV_TEMPLATE_INST);
14705 ret = instantiate_template_1 (tmpl, orig_args, complain);
14706 timevar_pop (TV_TEMPLATE_INST);
14710 /* We're going to do deduction substitution on the type of TMPL, a function
14711 template. In C++11 mode, push into that access scope. In C++03 mode,
14712 disable access checking. */
14715 push_deduction_access_scope (tree tmpl)
14717 if (cxx_dialect >= cxx0x)
14719 int ptd = processing_template_decl;
14720 push_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14721 /* Preserve processing_template_decl across push_to_top_level. */
14722 if (ptd && !processing_template_decl)
14723 ++processing_template_decl;
14726 push_deferring_access_checks (dk_no_check);
14729 /* And pop back out. */
14732 pop_deduction_access_scope (tree tmpl)
14734 if (cxx_dialect >= cxx0x)
14735 pop_access_scope (DECL_TEMPLATE_RESULT (tmpl));
14737 pop_deferring_access_checks ();
14740 /* PARM is a template parameter pack for FN. Returns true iff
14741 PARM is used in a deducible way in the argument list of FN. */
14744 pack_deducible_p (tree parm, tree fn)
14746 tree t = FUNCTION_FIRST_USER_PARMTYPE (fn);
14747 for (; t; t = TREE_CHAIN (t))
14749 tree type = TREE_VALUE (t);
14751 if (!PACK_EXPANSION_P (type))
14753 for (packs = PACK_EXPANSION_PARAMETER_PACKS (type);
14754 packs; packs = TREE_CHAIN (packs))
14755 if (TREE_VALUE (packs) == parm)
14757 /* The template parameter pack is used in a function parameter
14758 pack. If this is the end of the parameter list, the
14759 template parameter pack is deducible. */
14760 if (TREE_CHAIN (t) == void_list_node)
14763 /* Otherwise, not. Well, it could be deduced from
14764 a non-pack parameter, but doing so would end up with
14765 a deduction mismatch, so don't bother. */
14769 /* The template parameter pack isn't used in any function parameter
14770 packs, but it might be used deeper, e.g. tuple<Args...>. */
14774 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
14775 NARGS elements of the arguments that are being used when calling
14776 it. TARGS is a vector into which the deduced template arguments
14779 Return zero for success, 2 for an incomplete match that doesn't resolve
14780 all the types, and 1 for complete failure. An error message will be
14781 printed only for an incomplete match.
14783 If FN is a conversion operator, or we are trying to produce a specific
14784 specialization, RETURN_TYPE is the return type desired.
14786 The EXPLICIT_TARGS are explicit template arguments provided via a
14789 The parameter STRICT is one of:
14792 We are deducing arguments for a function call, as in
14793 [temp.deduct.call].
14796 We are deducing arguments for a conversion function, as in
14797 [temp.deduct.conv].
14800 We are deducing arguments when doing an explicit instantiation
14801 as in [temp.explicit], when determining an explicit specialization
14802 as in [temp.expl.spec], or when taking the address of a function
14803 template, as in [temp.deduct.funcaddr]. */
14806 fn_type_unification (tree fn,
14807 tree explicit_targs,
14810 unsigned int nargs,
14812 unification_kind_t strict,
14820 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
14822 fntype = TREE_TYPE (fn);
14823 if (explicit_targs)
14827 The specified template arguments must match the template
14828 parameters in kind (i.e., type, nontype, template), and there
14829 must not be more arguments than there are parameters;
14830 otherwise type deduction fails.
14832 Nontype arguments must match the types of the corresponding
14833 nontype template parameters, or must be convertible to the
14834 types of the corresponding nontype parameters as specified in
14835 _temp.arg.nontype_, otherwise type deduction fails.
14837 All references in the function type of the function template
14838 to the corresponding template parameters are replaced by the
14839 specified template argument values. If a substitution in a
14840 template parameter or in the function type of the function
14841 template results in an invalid type, type deduction fails. */
14842 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
14843 int i, len = TREE_VEC_LENGTH (tparms);
14844 tree converted_args;
14845 bool incomplete = false;
14847 if (explicit_targs == error_mark_node)
14848 return unify_invalid (explain_p);
14851 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE,
14853 ? tf_warning_or_error
14855 /*require_all_args=*/false,
14856 /*use_default_args=*/false));
14857 if (converted_args == error_mark_node)
14860 /* Substitute the explicit args into the function type. This is
14861 necessary so that, for instance, explicitly declared function
14862 arguments can match null pointed constants. If we were given
14863 an incomplete set of explicit args, we must not do semantic
14864 processing during substitution as we could create partial
14866 for (i = 0; i < len; i++)
14868 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
14869 bool parameter_pack = false;
14870 tree targ = TREE_VEC_ELT (converted_args, i);
14872 /* Dig out the actual parm. */
14873 if (TREE_CODE (parm) == TYPE_DECL
14874 || TREE_CODE (parm) == TEMPLATE_DECL)
14876 parm = TREE_TYPE (parm);
14877 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
14879 else if (TREE_CODE (parm) == PARM_DECL)
14881 parm = DECL_INITIAL (parm);
14882 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
14885 if (!parameter_pack && targ == NULL_TREE)
14886 /* No explicit argument for this template parameter. */
14889 if (parameter_pack && pack_deducible_p (parm, fn))
14891 /* Mark the argument pack as "incomplete". We could
14892 still deduce more arguments during unification.
14893 We remove this mark in type_unification_real. */
14896 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
14897 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
14898 = ARGUMENT_PACK_ARGS (targ);
14901 /* We have some incomplete argument packs. */
14906 processing_template_decl += incomplete;
14907 fntype = deduction_tsubst_fntype (fn, converted_args,
14909 ? tf_warning_or_error
14911 processing_template_decl -= incomplete;
14913 if (fntype == error_mark_node)
14916 /* Place the explicitly specified arguments in TARGS. */
14917 for (i = NUM_TMPL_ARGS (converted_args); i--;)
14918 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
14921 /* Never do unification on the 'this' parameter. */
14922 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
14928 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
14929 new_args = XALLOCAVEC (tree, nargs + 1);
14930 new_args[0] = return_type;
14931 memcpy (new_args + 1, args, nargs * sizeof (tree));
14936 /* We allow incomplete unification without an error message here
14937 because the standard doesn't seem to explicitly prohibit it. Our
14938 callers must be ready to deal with unification failures in any
14940 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
14941 targs, parms, args, nargs, /*subr=*/0,
14942 strict, flags, explain_p);
14944 /* Now that we have bindings for all of the template arguments,
14945 ensure that the arguments deduced for the template template
14946 parameters have compatible template parameter lists. We cannot
14947 check this property before we have deduced all template
14948 arguments, because the template parameter types of a template
14949 template parameter might depend on prior template parameters
14950 deduced after the template template parameter. The following
14951 ill-formed example illustrates this issue:
14953 template<typename T, template<T> class C> void f(C<5>, T);
14955 template<int N> struct X {};
14958 f(X<5>(), 5l); // error: template argument deduction fails
14961 The template parameter list of 'C' depends on the template type
14962 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
14963 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
14964 time that we deduce 'C'. */
14966 && !template_template_parm_bindings_ok_p
14967 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
14968 return unify_inconsistent_template_template_parameters (explain_p);
14971 /* All is well so far. Now, check:
14975 When all template arguments have been deduced, all uses of
14976 template parameters in nondeduced contexts are replaced with
14977 the corresponding deduced argument values. If the
14978 substitution results in an invalid type, as described above,
14979 type deduction fails. */
14981 tree substed = deduction_tsubst_fntype (fn, targs,
14983 ? tf_warning_or_error
14985 if (substed == error_mark_node)
14988 /* If we're looking for an exact match, check that what we got
14989 is indeed an exact match. It might not be if some template
14990 parameters are used in non-deduced contexts. */
14991 if (strict == DEDUCE_EXACT)
14996 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
14998 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
14999 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
15000 if (!same_type_p (args[i], TREE_VALUE (sarg)))
15001 return unify_type_mismatch (explain_p, args[i],
15002 TREE_VALUE (sarg));
15009 /* Adjust types before performing type deduction, as described in
15010 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
15011 sections are symmetric. PARM is the type of a function parameter
15012 or the return type of the conversion function. ARG is the type of
15013 the argument passed to the call, or the type of the value
15014 initialized with the result of the conversion function.
15015 ARG_EXPR is the original argument expression, which may be null. */
15018 maybe_adjust_types_for_deduction (unification_kind_t strict,
15032 /* Swap PARM and ARG throughout the remainder of this
15033 function; the handling is precisely symmetric since PARM
15034 will initialize ARG rather than vice versa. */
15042 /* Core issue #873: Do the DR606 thing (see below) for these cases,
15043 too, but here handle it by stripping the reference from PARM
15044 rather than by adding it to ARG. */
15045 if (TREE_CODE (*parm) == REFERENCE_TYPE
15046 && TYPE_REF_IS_RVALUE (*parm)
15047 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
15048 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
15049 && TREE_CODE (*arg) == REFERENCE_TYPE
15050 && !TYPE_REF_IS_RVALUE (*arg))
15051 *parm = TREE_TYPE (*parm);
15052 /* Nothing else to do in this case. */
15056 gcc_unreachable ();
15059 if (TREE_CODE (*parm) != REFERENCE_TYPE)
15061 /* [temp.deduct.call]
15063 If P is not a reference type:
15065 --If A is an array type, the pointer type produced by the
15066 array-to-pointer standard conversion (_conv.array_) is
15067 used in place of A for type deduction; otherwise,
15069 --If A is a function type, the pointer type produced by
15070 the function-to-pointer standard conversion
15071 (_conv.func_) is used in place of A for type deduction;
15074 --If A is a cv-qualified type, the top level
15075 cv-qualifiers of A's type are ignored for type
15077 if (TREE_CODE (*arg) == ARRAY_TYPE)
15078 *arg = build_pointer_type (TREE_TYPE (*arg));
15079 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
15080 *arg = build_pointer_type (*arg);
15082 *arg = TYPE_MAIN_VARIANT (*arg);
15085 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
15086 of the form T&&, where T is a template parameter, and the argument
15087 is an lvalue, T is deduced as A& */
15088 if (TREE_CODE (*parm) == REFERENCE_TYPE
15089 && TYPE_REF_IS_RVALUE (*parm)
15090 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
15091 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
15092 && (arg_expr ? real_lvalue_p (arg_expr)
15093 /* try_one_overload doesn't provide an arg_expr, but
15094 functions are always lvalues. */
15095 : TREE_CODE (*arg) == FUNCTION_TYPE))
15096 *arg = build_reference_type (*arg);
15098 /* [temp.deduct.call]
15100 If P is a cv-qualified type, the top level cv-qualifiers
15101 of P's type are ignored for type deduction. If P is a
15102 reference type, the type referred to by P is used for
15104 *parm = TYPE_MAIN_VARIANT (*parm);
15105 if (TREE_CODE (*parm) == REFERENCE_TYPE)
15107 *parm = TREE_TYPE (*parm);
15108 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
15111 /* DR 322. For conversion deduction, remove a reference type on parm
15112 too (which has been swapped into ARG). */
15113 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
15114 *arg = TREE_TYPE (*arg);
15119 /* Subroutine of unify_one_argument. PARM is a function parameter of a
15120 template which does contain any deducible template parameters; check if
15121 ARG is a suitable match for it. STRICT, FLAGS and EXPLAIN_P are as in
15122 unify_one_argument. */
15125 check_non_deducible_conversion (tree parm, tree arg, int strict,
15126 int flags, bool explain_p)
15131 type = TREE_TYPE (arg);
15135 if (same_type_p (parm, type))
15136 return unify_success (explain_p);
15138 if (strict == DEDUCE_CONV)
15140 if (can_convert_arg (type, parm, NULL_TREE, flags))
15141 return unify_success (explain_p);
15143 else if (strict != DEDUCE_EXACT)
15145 if (can_convert_arg (parm, type,
15146 TYPE_P (arg) ? NULL_TREE : arg,
15148 return unify_success (explain_p);
15151 if (strict == DEDUCE_EXACT)
15152 return unify_type_mismatch (explain_p, parm, arg);
15154 return unify_arg_conversion (explain_p, parm, type, arg);
15157 /* Subroutine of type_unification_real and unify_pack_expansion to
15158 handle unification of a single P/A pair. Parameters are as
15159 for those functions. */
15162 unify_one_argument (tree tparms, tree targs, tree parm, tree arg,
15163 int subr, unification_kind_t strict, int flags,
15166 tree arg_expr = NULL_TREE;
15169 if (arg == error_mark_node || parm == error_mark_node)
15170 return unify_invalid (explain_p);
15171 if (arg == unknown_type_node)
15172 /* We can't deduce anything from this, but we might get all the
15173 template args from other function args. */
15174 return unify_success (explain_p);
15176 /* FIXME uses_deducible_template_parms */
15177 if (TYPE_P (parm) && !uses_template_parms (parm))
15178 return check_non_deducible_conversion (parm, arg, strict, flags,
15184 arg_strict = (UNIFY_ALLOW_OUTER_LEVEL
15185 | UNIFY_ALLOW_MORE_CV_QUAL
15186 | UNIFY_ALLOW_DERIVED);
15190 arg_strict = UNIFY_ALLOW_LESS_CV_QUAL;
15194 arg_strict = UNIFY_ALLOW_NONE;
15198 gcc_unreachable ();
15201 /* We only do these transformations if this is the top-level
15202 parameter_type_list in a call or declaration matching; in other
15203 situations (nested function declarators, template argument lists) we
15204 won't be comparing a type to an expression, and we don't do any type
15210 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
15211 if (type_unknown_p (arg))
15213 /* [temp.deduct.type] A template-argument can be
15214 deduced from a pointer to function or pointer
15215 to member function argument if the set of
15216 overloaded functions does not contain function
15217 templates and at most one of a set of
15218 overloaded functions provides a unique
15221 if (resolve_overloaded_unification
15222 (tparms, targs, parm, arg, strict,
15223 arg_strict, explain_p))
15224 return unify_success (explain_p);
15225 return unify_overload_resolution_failure (explain_p, arg);
15229 arg = unlowered_expr_type (arg);
15230 if (arg == error_mark_node)
15231 return unify_invalid (explain_p);
15235 maybe_adjust_types_for_deduction (strict, &parm, &arg, arg_expr);
15238 gcc_assert ((TYPE_P (parm) || TREE_CODE (parm) == TEMPLATE_DECL)
15239 == (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL));
15241 /* For deduction from an init-list we need the actual list. */
15242 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
15244 return unify (tparms, targs, parm, arg, arg_strict, explain_p);
15247 /* Most parms like fn_type_unification.
15249 If SUBR is 1, we're being called recursively (to unify the
15250 arguments of a function or method parameter of a function
15254 type_unification_real (tree tparms,
15258 unsigned int xnargs,
15260 unification_kind_t strict,
15266 int ntparms = TREE_VEC_LENGTH (tparms);
15267 int saw_undeduced = 0;
15270 unsigned int nargs;
15273 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
15274 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
15275 gcc_assert (ntparms > 0);
15277 /* Reset the number of non-defaulted template arguments contained
15279 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
15287 while (parms && parms != void_list_node
15290 parm = TREE_VALUE (parms);
15292 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION
15293 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node))
15294 /* For a function parameter pack that occurs at the end of the
15295 parameter-declaration-list, the type A of each remaining
15296 argument of the call is compared with the type P of the
15297 declarator-id of the function parameter pack. */
15300 parms = TREE_CHAIN (parms);
15302 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION)
15303 /* For a function parameter pack that does not occur at the
15304 end of the parameter-declaration-list, the type of the
15305 parameter pack is a non-deduced context. */
15311 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
15317 && parms != void_list_node
15318 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
15320 /* Unify the remaining arguments with the pack expansion type. */
15322 tree parmvec = make_tree_vec (1);
15324 /* Allocate a TREE_VEC and copy in all of the arguments */
15325 argvec = make_tree_vec (nargs - ia);
15326 for (i = 0; ia < nargs; ++ia, ++i)
15327 TREE_VEC_ELT (argvec, i) = args[ia];
15329 /* Copy the parameter into parmvec. */
15330 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
15331 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
15332 /*subr=*/subr, explain_p))
15335 /* Advance to the end of the list of parameters. */
15336 parms = TREE_CHAIN (parms);
15339 /* Fail if we've reached the end of the parm list, and more args
15340 are present, and the parm list isn't variadic. */
15341 if (ia < nargs && parms == void_list_node)
15342 return unify_too_many_arguments (explain_p, nargs, ia);
15343 /* Fail if parms are left and they don't have default values. */
15344 if (parms && parms != void_list_node
15345 && TREE_PURPOSE (parms) == NULL_TREE)
15347 unsigned int count = nargs;
15349 while (p && p != void_list_node)
15352 p = TREE_CHAIN (p);
15354 return unify_too_few_arguments (explain_p, ia, count);
15359 tsubst_flags_t complain = (explain_p
15360 ? tf_warning_or_error
15363 /* Check to see if we need another pass before we start clearing
15364 ARGUMENT_PACK_INCOMPLETE_P. */
15365 for (i = 0; i < ntparms; i++)
15367 tree targ = TREE_VEC_ELT (targs, i);
15368 tree tparm = TREE_VEC_ELT (tparms, i);
15370 if (targ || tparm == error_mark_node)
15372 tparm = TREE_VALUE (tparm);
15374 /* If this is an undeduced nontype parameter that depends on
15375 a type parameter, try another pass; its type may have been
15376 deduced from a later argument than the one from which
15377 this parameter can be deduced. */
15378 if (TREE_CODE (tparm) == PARM_DECL
15379 && uses_template_parms (TREE_TYPE (tparm))
15380 && !saw_undeduced++)
15384 for (i = 0; i < ntparms; i++)
15386 tree targ = TREE_VEC_ELT (targs, i);
15387 tree tparm = TREE_VEC_ELT (tparms, i);
15389 /* Clear the "incomplete" flags on all argument packs now so that
15390 substituting them into later default arguments works. */
15391 if (targ && ARGUMENT_PACK_P (targ))
15393 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
15394 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
15397 if (targ || tparm == error_mark_node)
15399 tparm = TREE_VALUE (tparm);
15401 /* Core issue #226 (C++0x) [temp.deduct]:
15403 If a template argument has not been deduced, its
15404 default template argument, if any, is used.
15406 When we are in C++98 mode, TREE_PURPOSE will either
15407 be NULL_TREE or ERROR_MARK_NODE, so we do not need
15408 to explicitly check cxx_dialect here. */
15409 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
15411 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
15412 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
15413 location_t save_loc = input_location;
15415 input_location = DECL_SOURCE_LOCATION (parm);
15416 arg = tsubst_template_arg (arg, targs, complain, NULL_TREE);
15417 arg = convert_template_argument (parm, arg, targs, complain,
15419 input_location = save_loc;
15420 if (arg == error_mark_node)
15424 TREE_VEC_ELT (targs, i) = arg;
15425 /* The position of the first default template argument,
15426 is also the number of non-defaulted arguments in TARGS.
15428 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15429 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
15434 /* If the type parameter is a parameter pack, then it will
15435 be deduced to an empty parameter pack. */
15436 if (template_parameter_pack_p (tparm))
15440 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
15442 arg = make_node (NONTYPE_ARGUMENT_PACK);
15443 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
15444 TREE_CONSTANT (arg) = 1;
15447 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
15449 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
15451 TREE_VEC_ELT (targs, i) = arg;
15455 return unify_parameter_deduction_failure (explain_p, tparm);
15458 #ifdef ENABLE_CHECKING
15459 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15460 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
15463 return unify_success (explain_p);
15466 /* Subroutine of type_unification_real. Args are like the variables
15467 at the call site. ARG is an overloaded function (or template-id);
15468 we try deducing template args from each of the overloads, and if
15469 only one succeeds, we go with that. Modifies TARGS and returns
15470 true on success. */
15473 resolve_overloaded_unification (tree tparms,
15477 unification_kind_t strict,
15481 tree tempargs = copy_node (targs);
15483 tree goodfn = NULL_TREE;
15486 if (TREE_CODE (arg) == ADDR_EXPR)
15488 arg = TREE_OPERAND (arg, 0);
15494 if (TREE_CODE (arg) == COMPONENT_REF)
15495 /* Handle `&x' where `x' is some static or non-static member
15497 arg = TREE_OPERAND (arg, 1);
15499 if (TREE_CODE (arg) == OFFSET_REF)
15500 arg = TREE_OPERAND (arg, 1);
15502 /* Strip baselink information. */
15503 if (BASELINK_P (arg))
15504 arg = BASELINK_FUNCTIONS (arg);
15506 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
15508 /* If we got some explicit template args, we need to plug them into
15509 the affected templates before we try to unify, in case the
15510 explicit args will completely resolve the templates in question. */
15513 tree expl_subargs = TREE_OPERAND (arg, 1);
15514 arg = TREE_OPERAND (arg, 0);
15516 for (; arg; arg = OVL_NEXT (arg))
15518 tree fn = OVL_CURRENT (arg);
15519 tree subargs, elem;
15521 if (TREE_CODE (fn) != TEMPLATE_DECL)
15524 ++processing_template_decl;
15525 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15526 expl_subargs, /*check_ret=*/false);
15527 if (subargs && !any_dependent_template_arguments_p (subargs))
15529 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
15530 if (try_one_overload (tparms, targs, tempargs, parm,
15531 elem, strict, sub_strict, addr_p, explain_p)
15532 && (!goodfn || !same_type_p (goodfn, elem)))
15540 --processing_template_decl;
15542 /* If no templates (or more than one) are fully resolved by the
15543 explicit arguments, this template-id is a non-deduced context; it
15544 could still be OK if we deduce all template arguments for the
15545 enclosing call through other arguments. */
15549 else if (TREE_CODE (arg) != OVERLOAD
15550 && TREE_CODE (arg) != FUNCTION_DECL)
15551 /* If ARG is, for example, "(0, &f)" then its type will be unknown
15552 -- but the deduction does not succeed because the expression is
15553 not just the function on its own. */
15556 for (; arg; arg = OVL_NEXT (arg))
15557 if (try_one_overload (tparms, targs, tempargs, parm,
15558 TREE_TYPE (OVL_CURRENT (arg)),
15559 strict, sub_strict, addr_p, explain_p)
15560 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
15562 goodfn = OVL_CURRENT (arg);
15566 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15567 to function or pointer to member function argument if the set of
15568 overloaded functions does not contain function templates and at most
15569 one of a set of overloaded functions provides a unique match.
15571 So if we found multiple possibilities, we return success but don't
15572 deduce anything. */
15576 int i = TREE_VEC_LENGTH (targs);
15578 if (TREE_VEC_ELT (tempargs, i))
15579 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
15587 /* Core DR 115: In contexts where deduction is done and fails, or in
15588 contexts where deduction is not done, if a template argument list is
15589 specified and it, along with any default template arguments, identifies
15590 a single function template specialization, then the template-id is an
15591 lvalue for the function template specialization. */
15594 resolve_nondeduced_context (tree orig_expr)
15596 tree expr, offset, baselink;
15599 if (!type_unknown_p (orig_expr))
15604 offset = NULL_TREE;
15605 baselink = NULL_TREE;
15607 if (TREE_CODE (expr) == ADDR_EXPR)
15609 expr = TREE_OPERAND (expr, 0);
15612 if (TREE_CODE (expr) == OFFSET_REF)
15615 expr = TREE_OPERAND (expr, 1);
15617 if (BASELINK_P (expr))
15620 expr = BASELINK_FUNCTIONS (expr);
15623 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
15626 tree goodfn = NULL_TREE;
15628 /* If we got some explicit template args, we need to plug them into
15629 the affected templates before we try to unify, in case the
15630 explicit args will completely resolve the templates in question. */
15632 tree expl_subargs = TREE_OPERAND (expr, 1);
15633 tree arg = TREE_OPERAND (expr, 0);
15634 tree badfn = NULL_TREE;
15635 tree badargs = NULL_TREE;
15637 for (; arg; arg = OVL_NEXT (arg))
15639 tree fn = OVL_CURRENT (arg);
15640 tree subargs, elem;
15642 if (TREE_CODE (fn) != TEMPLATE_DECL)
15645 ++processing_template_decl;
15646 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
15647 expl_subargs, /*check_ret=*/false);
15648 if (subargs && !any_dependent_template_arguments_p (subargs))
15650 elem = instantiate_template (fn, subargs, tf_none);
15651 if (elem == error_mark_node)
15656 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
15662 --processing_template_decl;
15666 mark_used (goodfn);
15669 expr = build_baselink (BASELINK_BINFO (baselink),
15670 BASELINK_ACCESS_BINFO (baselink),
15671 expr, BASELINK_OPTYPE (baselink));
15675 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
15676 expr = build_offset_ref (base, expr, addr);
15679 expr = cp_build_addr_expr (expr, tf_warning_or_error);
15682 else if (good == 0 && badargs)
15683 /* There were no good options and at least one bad one, so let the
15684 user know what the problem is. */
15685 instantiate_template (badfn, badargs, tf_warning_or_error);
15690 /* Subroutine of resolve_overloaded_unification; does deduction for a single
15691 overload. Fills TARGS with any deduced arguments, or error_mark_node if
15692 different overloads deduce different arguments for a given parm.
15693 ADDR_P is true if the expression for which deduction is being
15694 performed was of the form "& fn" rather than simply "fn".
15696 Returns 1 on success. */
15699 try_one_overload (tree tparms,
15704 unification_kind_t strict,
15713 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15714 to function or pointer to member function argument if the set of
15715 overloaded functions does not contain function templates and at most
15716 one of a set of overloaded functions provides a unique match.
15718 So if this is a template, just return success. */
15720 if (uses_template_parms (arg))
15723 if (TREE_CODE (arg) == METHOD_TYPE)
15724 arg = build_ptrmemfunc_type (build_pointer_type (arg));
15726 arg = build_pointer_type (arg);
15728 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
15730 /* We don't copy orig_targs for this because if we have already deduced
15731 some template args from previous args, unify would complain when we
15732 try to deduce a template parameter for the same argument, even though
15733 there isn't really a conflict. */
15734 nargs = TREE_VEC_LENGTH (targs);
15735 tempargs = make_tree_vec (nargs);
15737 if (unify (tparms, tempargs, parm, arg, sub_strict, explain_p))
15740 /* First make sure we didn't deduce anything that conflicts with
15741 explicitly specified args. */
15742 for (i = nargs; i--; )
15744 tree elt = TREE_VEC_ELT (tempargs, i);
15745 tree oldelt = TREE_VEC_ELT (orig_targs, i);
15749 else if (uses_template_parms (elt))
15750 /* Since we're unifying against ourselves, we will fill in
15751 template args used in the function parm list with our own
15752 template parms. Discard them. */
15753 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
15754 else if (oldelt && !template_args_equal (oldelt, elt))
15758 for (i = nargs; i--; )
15760 tree elt = TREE_VEC_ELT (tempargs, i);
15763 TREE_VEC_ELT (targs, i) = elt;
15769 /* PARM is a template class (perhaps with unbound template
15770 parameters). ARG is a fully instantiated type. If ARG can be
15771 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
15772 TARGS are as for unify. */
15775 try_class_unification (tree tparms, tree targs, tree parm, tree arg,
15778 tree copy_of_targs;
15780 if (!CLASSTYPE_TEMPLATE_INFO (arg)
15781 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
15782 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
15785 /* We need to make a new template argument vector for the call to
15786 unify. If we used TARGS, we'd clutter it up with the result of
15787 the attempted unification, even if this class didn't work out.
15788 We also don't want to commit ourselves to all the unifications
15789 we've already done, since unification is supposed to be done on
15790 an argument-by-argument basis. In other words, consider the
15791 following pathological case:
15793 template <int I, int J, int K>
15796 template <int I, int J>
15797 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
15799 template <int I, int J, int K>
15800 void f(S<I, J, K>, S<I, I, I>);
15809 Now, by the time we consider the unification involving `s2', we
15810 already know that we must have `f<0, 0, 0>'. But, even though
15811 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
15812 because there are two ways to unify base classes of S<0, 1, 2>
15813 with S<I, I, I>. If we kept the already deduced knowledge, we
15814 would reject the possibility I=1. */
15815 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
15817 /* If unification failed, we're done. */
15818 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
15819 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE, explain_p))
15825 /* Given a template type PARM and a class type ARG, find the unique
15826 base type in ARG that is an instance of PARM. We do not examine
15827 ARG itself; only its base-classes. If there is not exactly one
15828 appropriate base class, return NULL_TREE. PARM may be the type of
15829 a partial specialization, as well as a plain template type. Used
15832 static enum template_base_result
15833 get_template_base (tree tparms, tree targs, tree parm, tree arg,
15834 bool explain_p, tree *result)
15836 tree rval = NULL_TREE;
15839 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
15841 binfo = TYPE_BINFO (complete_type (arg));
15844 /* The type could not be completed. */
15845 *result = NULL_TREE;
15846 return tbr_incomplete_type;
15849 /* Walk in inheritance graph order. The search order is not
15850 important, and this avoids multiple walks of virtual bases. */
15851 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
15853 tree r = try_class_unification (tparms, targs, parm,
15854 BINFO_TYPE (binfo), explain_p);
15858 /* If there is more than one satisfactory baseclass, then:
15862 If they yield more than one possible deduced A, the type
15866 if (rval && !same_type_p (r, rval))
15868 *result = NULL_TREE;
15869 return tbr_ambiguous_baseclass;
15877 return tbr_success;
15880 /* Returns the level of DECL, which declares a template parameter. */
15883 template_decl_level (tree decl)
15885 switch (TREE_CODE (decl))
15888 case TEMPLATE_DECL:
15889 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
15892 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
15895 gcc_unreachable ();
15900 /* Decide whether ARG can be unified with PARM, considering only the
15901 cv-qualifiers of each type, given STRICT as documented for unify.
15902 Returns nonzero iff the unification is OK on that basis. */
15905 check_cv_quals_for_unify (int strict, tree arg, tree parm)
15907 int arg_quals = cp_type_quals (arg);
15908 int parm_quals = cp_type_quals (parm);
15910 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15911 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15913 /* Although a CVR qualifier is ignored when being applied to a
15914 substituted template parameter ([8.3.2]/1 for example), that
15915 does not allow us to unify "const T" with "int&" because both
15916 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
15917 It is ok when we're allowing additional CV qualifiers
15918 at the outer level [14.8.2.1]/3,1st bullet. */
15919 if ((TREE_CODE (arg) == REFERENCE_TYPE
15920 || TREE_CODE (arg) == FUNCTION_TYPE
15921 || TREE_CODE (arg) == METHOD_TYPE)
15922 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
15925 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
15926 && (parm_quals & TYPE_QUAL_RESTRICT))
15930 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
15931 && (arg_quals & parm_quals) != parm_quals)
15934 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
15935 && (parm_quals & arg_quals) != arg_quals)
15941 /* Determines the LEVEL and INDEX for the template parameter PARM. */
15943 template_parm_level_and_index (tree parm, int* level, int* index)
15945 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
15946 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
15947 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
15949 *index = TEMPLATE_TYPE_IDX (parm);
15950 *level = TEMPLATE_TYPE_LEVEL (parm);
15954 *index = TEMPLATE_PARM_IDX (parm);
15955 *level = TEMPLATE_PARM_LEVEL (parm);
15959 #define RECUR_AND_CHECK_FAILURE(TP, TA, P, A, S, EP) \
15961 if (unify (TP, TA, P, A, S, EP)) \
15965 /* Unifies the remaining arguments in PACKED_ARGS with the pack
15966 expansion at the end of PACKED_PARMS. Returns 0 if the type
15967 deduction succeeds, 1 otherwise. STRICT is the same as in
15968 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
15969 call argument list. We'll need to adjust the arguments to make them
15970 types. SUBR tells us if this is from a recursive call to
15971 type_unification_real, or for comparing two template argument
15975 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
15976 tree packed_args, unification_kind_t strict,
15977 bool subr, bool explain_p)
15980 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
15981 tree pattern = PACK_EXPANSION_PATTERN (parm);
15982 tree pack, packs = NULL_TREE;
15983 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
15984 int len = TREE_VEC_LENGTH (packed_args);
15986 /* Determine the parameter packs we will be deducing from the
15987 pattern, and record their current deductions. */
15988 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
15989 pack; pack = TREE_CHAIN (pack))
15991 tree parm_pack = TREE_VALUE (pack);
15994 /* Determine the index and level of this parameter pack. */
15995 template_parm_level_and_index (parm_pack, &level, &idx);
15997 /* Keep track of the parameter packs and their corresponding
15999 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
16000 TREE_TYPE (packs) = make_tree_vec (len - start);
16003 /* Loop through all of the arguments that have not yet been
16004 unified and unify each with the pattern. */
16005 for (i = start; i < len; i++)
16008 bool any_explicit = false;
16009 tree arg = TREE_VEC_ELT (packed_args, i);
16011 /* For each parameter pack, set its TMPL_ARG to either NULL_TREE
16012 or the element of its argument pack at the current index if
16013 this argument was explicitly specified. */
16014 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16018 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16021 if (TREE_VALUE (pack)
16022 && (pargs = ARGUMENT_PACK_EXPLICIT_ARGS (TREE_VALUE (pack)))
16023 && (i < TREE_VEC_LENGTH (pargs)))
16025 any_explicit = true;
16026 arg = TREE_VEC_ELT (pargs, i);
16028 TMPL_ARG (targs, level, idx) = arg;
16031 /* If we had explicit template arguments, substitute them into the
16032 pattern before deduction. */
16035 /* Some arguments might still be unspecified or dependent. */
16037 ++processing_template_decl;
16038 dependent = any_dependent_template_arguments_p (targs);
16040 --processing_template_decl;
16041 parm = tsubst (pattern, targs,
16042 explain_p ? tf_warning_or_error : tf_none,
16045 --processing_template_decl;
16046 if (parm == error_mark_node)
16052 /* Unify the pattern with the current argument. */
16053 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
16054 LOOKUP_IMPLICIT, explain_p))
16057 /* For each parameter pack, collect the deduced value. */
16058 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16061 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16063 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
16064 TMPL_ARG (targs, level, idx);
16068 /* Verify that the results of unification with the parameter packs
16069 produce results consistent with what we've seen before, and make
16070 the deduced argument packs available. */
16071 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16073 tree old_pack = TREE_VALUE (pack);
16074 tree new_args = TREE_TYPE (pack);
16075 int i, len = TREE_VEC_LENGTH (new_args);
16077 bool nondeduced_p = false;
16079 /* By default keep the original deduced argument pack.
16080 If necessary, more specific code is going to update the
16081 resulting deduced argument later down in this function. */
16082 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16083 TMPL_ARG (targs, level, idx) = old_pack;
16085 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
16086 actually deduce anything. */
16087 for (i = 0; i < len && !nondeduced_p; ++i)
16088 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
16089 nondeduced_p = true;
16093 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
16095 /* If we had fewer function args than explicit template args,
16096 just use the explicits. */
16097 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
16098 int explicit_len = TREE_VEC_LENGTH (explicit_args);
16099 if (len < explicit_len)
16100 new_args = explicit_args;
16106 /* Build the deduced *_ARGUMENT_PACK. */
16107 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
16109 result = make_node (NONTYPE_ARGUMENT_PACK);
16110 TREE_TYPE (result) =
16111 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
16112 TREE_CONSTANT (result) = 1;
16115 result = cxx_make_type (TYPE_ARGUMENT_PACK);
16117 SET_ARGUMENT_PACK_ARGS (result, new_args);
16119 /* Note the deduced argument packs for this parameter
16121 TMPL_ARG (targs, level, idx) = result;
16123 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
16124 && (ARGUMENT_PACK_ARGS (old_pack)
16125 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
16127 /* We only had the explicitly-provided arguments before, but
16128 now we have a complete set of arguments. */
16129 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
16131 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
16132 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
16133 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
16137 tree bad_old_arg = NULL_TREE, bad_new_arg = NULL_TREE;
16138 tree old_args = ARGUMENT_PACK_ARGS (old_pack);
16140 if (!comp_template_args_with_info (old_args, new_args,
16141 &bad_old_arg, &bad_new_arg))
16142 /* Inconsistent unification of this parameter pack. */
16143 return unify_parameter_pack_inconsistent (explain_p,
16149 return unify_success (explain_p);
16152 /* Deduce the value of template parameters. TPARMS is the (innermost)
16153 set of template parameters to a template. TARGS is the bindings
16154 for those template parameters, as determined thus far; TARGS may
16155 include template arguments for outer levels of template parameters
16156 as well. PARM is a parameter to a template function, or a
16157 subcomponent of that parameter; ARG is the corresponding argument.
16158 This function attempts to match PARM with ARG in a manner
16159 consistent with the existing assignments in TARGS. If more values
16160 are deduced, then TARGS is updated.
16162 Returns 0 if the type deduction succeeds, 1 otherwise. The
16163 parameter STRICT is a bitwise or of the following flags:
16166 Require an exact match between PARM and ARG.
16167 UNIFY_ALLOW_MORE_CV_QUAL:
16168 Allow the deduced ARG to be more cv-qualified (by qualification
16169 conversion) than ARG.
16170 UNIFY_ALLOW_LESS_CV_QUAL:
16171 Allow the deduced ARG to be less cv-qualified than ARG.
16172 UNIFY_ALLOW_DERIVED:
16173 Allow the deduced ARG to be a template base class of ARG,
16174 or a pointer to a template base class of the type pointed to by
16176 UNIFY_ALLOW_INTEGER:
16177 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
16178 case for more information.
16179 UNIFY_ALLOW_OUTER_LEVEL:
16180 This is the outermost level of a deduction. Used to determine validity
16181 of qualification conversions. A valid qualification conversion must
16182 have const qualified pointers leading up to the inner type which
16183 requires additional CV quals, except at the outer level, where const
16184 is not required [conv.qual]. It would be normal to set this flag in
16185 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
16186 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
16187 This is the outermost level of a deduction, and PARM can be more CV
16188 qualified at this point.
16189 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
16190 This is the outermost level of a deduction, and PARM can be less CV
16191 qualified at this point. */
16194 unify (tree tparms, tree targs, tree parm, tree arg, int strict,
16200 int strict_in = strict;
16202 /* I don't think this will do the right thing with respect to types.
16203 But the only case I've seen it in so far has been array bounds, where
16204 signedness is the only information lost, and I think that will be
16206 while (TREE_CODE (parm) == NOP_EXPR)
16207 parm = TREE_OPERAND (parm, 0);
16209 if (arg == error_mark_node)
16210 return unify_invalid (explain_p);
16211 if (arg == unknown_type_node
16212 || arg == init_list_type_node)
16213 /* We can't deduce anything from this, but we might get all the
16214 template args from other function args. */
16215 return unify_success (explain_p);
16217 /* If PARM uses template parameters, then we can't bail out here,
16218 even if ARG == PARM, since we won't record unifications for the
16219 template parameters. We might need them if we're trying to
16220 figure out which of two things is more specialized. */
16221 if (arg == parm && !uses_template_parms (parm))
16222 return unify_success (explain_p);
16224 /* Handle init lists early, so the rest of the function can assume
16225 we're dealing with a type. */
16226 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
16230 tree orig_parm = parm;
16232 /* Replace T with std::initializer_list<T> for deduction. */
16233 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16234 && flag_deduce_init_list)
16235 parm = listify (parm);
16237 if (!is_std_init_list (parm))
16238 /* We can only deduce from an initializer list argument if the
16239 parameter is std::initializer_list; otherwise this is a
16240 non-deduced context. */
16241 return unify_success (explain_p);
16243 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
16245 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
16247 int elt_strict = strict;
16249 if (elt == error_mark_node)
16250 return unify_invalid (explain_p);
16252 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
16254 tree type = TREE_TYPE (elt);
16255 /* It should only be possible to get here for a call. */
16256 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
16257 elt_strict |= maybe_adjust_types_for_deduction
16258 (DEDUCE_CALL, &elttype, &type, elt);
16262 RECUR_AND_CHECK_FAILURE (tparms, targs, elttype, elt, elt_strict,
16266 /* If the std::initializer_list<T> deduction worked, replace the
16267 deduced A with std::initializer_list<A>. */
16268 if (orig_parm != parm)
16270 idx = TEMPLATE_TYPE_IDX (orig_parm);
16271 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16272 targ = listify (targ);
16273 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
16275 return unify_success (explain_p);
16278 /* Immediately reject some pairs that won't unify because of
16279 cv-qualification mismatches. */
16280 if (TREE_CODE (arg) == TREE_CODE (parm)
16282 /* It is the elements of the array which hold the cv quals of an array
16283 type, and the elements might be template type parms. We'll check
16284 when we recurse. */
16285 && TREE_CODE (arg) != ARRAY_TYPE
16286 /* We check the cv-qualifiers when unifying with template type
16287 parameters below. We want to allow ARG `const T' to unify with
16288 PARM `T' for example, when computing which of two templates
16289 is more specialized, for example. */
16290 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
16291 && !check_cv_quals_for_unify (strict_in, arg, parm))
16292 return unify_cv_qual_mismatch (explain_p, parm, arg);
16294 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
16295 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
16296 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
16297 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
16298 strict &= ~UNIFY_ALLOW_DERIVED;
16299 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
16300 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
16302 switch (TREE_CODE (parm))
16304 case TYPENAME_TYPE:
16306 case UNBOUND_CLASS_TEMPLATE:
16307 /* In a type which contains a nested-name-specifier, template
16308 argument values cannot be deduced for template parameters used
16309 within the nested-name-specifier. */
16310 return unify_success (explain_p);
16312 case TEMPLATE_TYPE_PARM:
16313 case TEMPLATE_TEMPLATE_PARM:
16314 case BOUND_TEMPLATE_TEMPLATE_PARM:
16315 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16316 if (tparm == error_mark_node)
16317 return unify_invalid (explain_p);
16319 if (TEMPLATE_TYPE_LEVEL (parm)
16320 != template_decl_level (tparm))
16321 /* The PARM is not one we're trying to unify. Just check
16322 to see if it matches ARG. */
16324 if (TREE_CODE (arg) == TREE_CODE (parm)
16325 && same_type_p (parm, arg))
16326 return unify_success (explain_p);
16328 return unify_type_mismatch (explain_p, parm, arg);
16330 idx = TEMPLATE_TYPE_IDX (parm);
16331 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16332 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
16333 if (tparm == error_mark_node)
16334 return unify_invalid (explain_p);
16336 /* Check for mixed types and values. */
16337 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16338 && TREE_CODE (tparm) != TYPE_DECL)
16339 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16340 && TREE_CODE (tparm) != TEMPLATE_DECL))
16341 gcc_unreachable ();
16343 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16345 /* ARG must be constructed from a template class or a template
16346 template parameter. */
16347 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
16348 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
16349 return unify_template_deduction_failure (explain_p, parm, arg);
16352 tree parmvec = TYPE_TI_ARGS (parm);
16353 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
16354 tree full_argvec = add_to_template_args (targs, argvec);
16356 = DECL_INNERMOST_TEMPLATE_PARMS
16357 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
16359 int parm_variadic_p = 0;
16361 /* The resolution to DR150 makes clear that default
16362 arguments for an N-argument may not be used to bind T
16363 to a template template parameter with fewer than N
16364 parameters. It is not safe to permit the binding of
16365 default arguments as an extension, as that may change
16366 the meaning of a conforming program. Consider:
16368 struct Dense { static const unsigned int dim = 1; };
16370 template <template <typename> class View,
16372 void operator+(float, View<Block> const&);
16374 template <typename Block,
16375 unsigned int Dim = Block::dim>
16376 struct Lvalue_proxy { operator float() const; };
16380 Lvalue_proxy<Dense> p;
16385 Here, if Lvalue_proxy is permitted to bind to View, then
16386 the global operator+ will be used; if they are not, the
16387 Lvalue_proxy will be converted to float. */
16388 if (coerce_template_parms (parm_parms,
16390 TYPE_TI_TEMPLATE (parm),
16392 ? tf_warning_or_error
16394 /*require_all_args=*/true,
16395 /*use_default_args=*/false)
16396 == error_mark_node)
16399 /* Deduce arguments T, i from TT<T> or TT<i>.
16400 We check each element of PARMVEC and ARGVEC individually
16401 rather than the whole TREE_VEC since they can have
16402 different number of elements. */
16404 parmvec = expand_template_argument_pack (parmvec);
16405 argvec = expand_template_argument_pack (argvec);
16407 len = TREE_VEC_LENGTH (parmvec);
16409 /* Check if the parameters end in a pack, making them
16412 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
16413 parm_variadic_p = 1;
16415 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
16416 return unify_too_few_arguments (explain_p,
16417 TREE_VEC_LENGTH (argvec), len);
16419 for (i = 0; i < len - parm_variadic_p; ++i)
16421 RECUR_AND_CHECK_FAILURE (tparms, targs,
16422 TREE_VEC_ELT (parmvec, i),
16423 TREE_VEC_ELT (argvec, i),
16424 UNIFY_ALLOW_NONE, explain_p);
16427 if (parm_variadic_p
16428 && unify_pack_expansion (tparms, targs,
16431 /*subr=*/true, explain_p))
16434 arg = TYPE_TI_TEMPLATE (arg);
16436 /* Fall through to deduce template name. */
16439 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16440 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16442 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
16444 /* Simple cases: Value already set, does match or doesn't. */
16445 if (targ != NULL_TREE && template_args_equal (targ, arg))
16446 return unify_success (explain_p);
16448 return unify_inconsistency (explain_p, parm, targ, arg);
16452 /* If PARM is `const T' and ARG is only `int', we don't have
16453 a match unless we are allowing additional qualification.
16454 If ARG is `const int' and PARM is just `T' that's OK;
16455 that binds `const int' to `T'. */
16456 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
16458 return unify_cv_qual_mismatch (explain_p, parm, arg);
16460 /* Consider the case where ARG is `const volatile int' and
16461 PARM is `const T'. Then, T should be `volatile int'. */
16462 arg = cp_build_qualified_type_real
16463 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
16464 if (arg == error_mark_node)
16465 return unify_invalid (explain_p);
16467 /* Simple cases: Value already set, does match or doesn't. */
16468 if (targ != NULL_TREE && same_type_p (targ, arg))
16469 return unify_success (explain_p);
16471 return unify_inconsistency (explain_p, parm, targ, arg);
16473 /* Make sure that ARG is not a variable-sized array. (Note
16474 that were talking about variable-sized arrays (like
16475 `int[n]'), rather than arrays of unknown size (like
16476 `int[]').) We'll get very confused by such a type since
16477 the bound of the array is not constant, and therefore
16478 not mangleable. Besides, such types are not allowed in
16479 ISO C++, so we can do as we please here. We do allow
16480 them for 'auto' deduction, since that isn't ABI-exposed. */
16481 if (!is_auto (parm) && variably_modified_type_p (arg, NULL_TREE))
16482 return unify_vla_arg (explain_p, arg);
16484 /* Strip typedefs as in convert_template_argument. */
16485 arg = canonicalize_type_argument (arg, tf_none);
16488 /* If ARG is a parameter pack or an expansion, we cannot unify
16489 against it unless PARM is also a parameter pack. */
16490 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16491 && !template_parameter_pack_p (parm))
16492 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16494 /* If the argument deduction results is a METHOD_TYPE,
16495 then there is a problem.
16496 METHOD_TYPE doesn't map to any real C++ type the result of
16497 the deduction can not be of that type. */
16498 if (TREE_CODE (arg) == METHOD_TYPE)
16499 return unify_method_type_error (explain_p, arg);
16501 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16502 return unify_success (explain_p);
16504 case TEMPLATE_PARM_INDEX:
16505 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16506 if (tparm == error_mark_node)
16507 return unify_invalid (explain_p);
16509 if (TEMPLATE_PARM_LEVEL (parm)
16510 != template_decl_level (tparm))
16512 /* The PARM is not one we're trying to unify. Just check
16513 to see if it matches ARG. */
16514 int result = !(TREE_CODE (arg) == TREE_CODE (parm)
16515 && cp_tree_equal (parm, arg));
16517 unify_expression_unequal (explain_p, parm, arg);
16521 idx = TEMPLATE_PARM_IDX (parm);
16522 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16526 int x = !cp_tree_equal (targ, arg);
16528 unify_inconsistency (explain_p, parm, targ, arg);
16532 /* [temp.deduct.type] If, in the declaration of a function template
16533 with a non-type template-parameter, the non-type
16534 template-parameter is used in an expression in the function
16535 parameter-list and, if the corresponding template-argument is
16536 deduced, the template-argument type shall match the type of the
16537 template-parameter exactly, except that a template-argument
16538 deduced from an array bound may be of any integral type.
16539 The non-type parameter might use already deduced type parameters. */
16540 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
16541 if (!TREE_TYPE (arg))
16542 /* Template-parameter dependent expression. Just accept it for now.
16543 It will later be processed in convert_template_argument. */
16545 else if (same_type_p (TREE_TYPE (arg), tparm))
16547 else if ((strict & UNIFY_ALLOW_INTEGER)
16548 && (TREE_CODE (tparm) == INTEGER_TYPE
16549 || TREE_CODE (tparm) == BOOLEAN_TYPE))
16550 /* Convert the ARG to the type of PARM; the deduced non-type
16551 template argument must exactly match the types of the
16552 corresponding parameter. */
16553 arg = fold (build_nop (tparm, arg));
16554 else if (uses_template_parms (tparm))
16555 /* We haven't deduced the type of this parameter yet. Try again
16557 return unify_success (explain_p);
16559 return unify_type_mismatch (explain_p, tparm, arg);
16561 /* If ARG is a parameter pack or an expansion, we cannot unify
16562 against it unless PARM is also a parameter pack. */
16563 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16564 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
16565 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16567 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16568 return unify_success (explain_p);
16572 /* A pointer-to-member constant can be unified only with
16573 another constant. */
16574 if (TREE_CODE (arg) != PTRMEM_CST)
16575 return unify_ptrmem_cst_mismatch (explain_p, parm, arg);
16577 /* Just unify the class member. It would be useless (and possibly
16578 wrong, depending on the strict flags) to unify also
16579 PTRMEM_CST_CLASS, because we want to be sure that both parm and
16580 arg refer to the same variable, even if through different
16581 classes. For instance:
16583 struct A { int x; };
16586 Unification of &A::x and &B::x must succeed. */
16587 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
16588 PTRMEM_CST_MEMBER (arg), strict, explain_p);
16593 if (TREE_CODE (arg) != POINTER_TYPE)
16594 return unify_type_mismatch (explain_p, parm, arg);
16596 /* [temp.deduct.call]
16598 A can be another pointer or pointer to member type that can
16599 be converted to the deduced A via a qualification
16600 conversion (_conv.qual_).
16602 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
16603 This will allow for additional cv-qualification of the
16604 pointed-to types if appropriate. */
16606 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
16607 /* The derived-to-base conversion only persists through one
16608 level of pointers. */
16609 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
16611 return unify (tparms, targs, TREE_TYPE (parm),
16612 TREE_TYPE (arg), strict, explain_p);
16615 case REFERENCE_TYPE:
16616 if (TREE_CODE (arg) != REFERENCE_TYPE)
16617 return unify_type_mismatch (explain_p, parm, arg);
16618 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16619 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16622 if (TREE_CODE (arg) != ARRAY_TYPE)
16623 return unify_type_mismatch (explain_p, parm, arg);
16624 if ((TYPE_DOMAIN (parm) == NULL_TREE)
16625 != (TYPE_DOMAIN (arg) == NULL_TREE))
16626 return unify_type_mismatch (explain_p, parm, arg);
16627 if (TYPE_DOMAIN (parm) != NULL_TREE)
16634 /* Our representation of array types uses "N - 1" as the
16635 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
16636 not an integer constant. We cannot unify arbitrarily
16637 complex expressions, so we eliminate the MINUS_EXPRs
16639 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
16640 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
16643 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
16644 parm_max = TREE_OPERAND (parm_max, 0);
16646 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
16647 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
16650 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
16651 trying to unify the type of a variable with the type
16652 of a template parameter. For example:
16654 template <unsigned int N>
16655 void f (char (&) [N]);
16662 Here, the type of the ARG will be "int [g(i)]", and
16663 may be a SAVE_EXPR, etc. */
16664 if (TREE_CODE (arg_max) != MINUS_EXPR)
16665 return unify_vla_arg (explain_p, arg);
16666 arg_max = TREE_OPERAND (arg_max, 0);
16669 /* If only one of the bounds used a MINUS_EXPR, compensate
16670 by adding one to the other bound. */
16671 if (parm_cst && !arg_cst)
16672 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
16676 else if (arg_cst && !parm_cst)
16677 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
16682 RECUR_AND_CHECK_FAILURE (tparms, targs, parm_max, arg_max,
16683 UNIFY_ALLOW_INTEGER, explain_p);
16685 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16686 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16693 case ENUMERAL_TYPE:
16696 if (TREE_CODE (arg) != TREE_CODE (parm))
16697 return unify_type_mismatch (explain_p, parm, arg);
16699 /* We have already checked cv-qualification at the top of the
16701 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
16702 return unify_type_mismatch (explain_p, parm, arg);
16704 /* As far as unification is concerned, this wins. Later checks
16705 will invalidate it if necessary. */
16706 return unify_success (explain_p);
16708 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
16709 /* Type INTEGER_CST can come from ordinary constant template args. */
16711 while (TREE_CODE (arg) == NOP_EXPR)
16712 arg = TREE_OPERAND (arg, 0);
16714 if (TREE_CODE (arg) != INTEGER_CST)
16715 return unify_template_argument_mismatch (explain_p, parm, arg);
16716 return (tree_int_cst_equal (parm, arg)
16717 ? unify_success (explain_p)
16718 : unify_template_argument_mismatch (explain_p, parm, arg));
16722 int i, len, argslen;
16723 int parm_variadic_p = 0;
16725 if (TREE_CODE (arg) != TREE_VEC)
16726 return unify_template_argument_mismatch (explain_p, parm, arg);
16728 len = TREE_VEC_LENGTH (parm);
16729 argslen = TREE_VEC_LENGTH (arg);
16731 /* Check for pack expansions in the parameters. */
16732 for (i = 0; i < len; ++i)
16734 if (PACK_EXPANSION_P (TREE_VEC_ELT (parm, i)))
16737 /* We can unify against something with a trailing
16739 parm_variadic_p = 1;
16741 /* [temp.deduct.type]/9: If the template argument list of
16742 P contains a pack expansion that is not the last
16743 template argument, the entire template argument list
16744 is a non-deduced context. */
16745 return unify_success (explain_p);
16749 /* If we don't have enough arguments to satisfy the parameters
16750 (not counting the pack expression at the end), or we have
16751 too many arguments for a parameter list that doesn't end in
16752 a pack expression, we can't unify. */
16753 if (parm_variadic_p
16754 ? argslen < len - parm_variadic_p
16756 return unify_arity (explain_p, TREE_VEC_LENGTH (arg), len);
16758 /* Unify all of the parameters that precede the (optional)
16759 pack expression. */
16760 for (i = 0; i < len - parm_variadic_p; ++i)
16762 RECUR_AND_CHECK_FAILURE (tparms, targs,
16763 TREE_VEC_ELT (parm, i),
16764 TREE_VEC_ELT (arg, i),
16765 UNIFY_ALLOW_NONE, explain_p);
16767 if (parm_variadic_p)
16768 return unify_pack_expansion (tparms, targs, parm, arg,
16770 /*subr=*/true, explain_p);
16771 return unify_success (explain_p);
16776 if (TREE_CODE (arg) != TREE_CODE (parm))
16777 return unify_type_mismatch (explain_p, parm, arg);
16779 if (TYPE_PTRMEMFUNC_P (parm))
16781 if (!TYPE_PTRMEMFUNC_P (arg))
16782 return unify_type_mismatch (explain_p, parm, arg);
16784 return unify (tparms, targs,
16785 TYPE_PTRMEMFUNC_FN_TYPE (parm),
16786 TYPE_PTRMEMFUNC_FN_TYPE (arg),
16787 strict, explain_p);
16790 if (CLASSTYPE_TEMPLATE_INFO (parm))
16792 tree t = NULL_TREE;
16794 if (strict_in & UNIFY_ALLOW_DERIVED)
16796 /* First, we try to unify the PARM and ARG directly. */
16797 t = try_class_unification (tparms, targs,
16798 parm, arg, explain_p);
16802 /* Fallback to the special case allowed in
16803 [temp.deduct.call]:
16805 If P is a class, and P has the form
16806 template-id, then A can be a derived class of
16807 the deduced A. Likewise, if P is a pointer to
16808 a class of the form template-id, A can be a
16809 pointer to a derived class pointed to by the
16811 enum template_base_result r;
16812 r = get_template_base (tparms, targs, parm, arg,
16816 return unify_no_common_base (explain_p, r, parm, arg);
16819 else if (CLASSTYPE_TEMPLATE_INFO (arg)
16820 && (CLASSTYPE_TI_TEMPLATE (parm)
16821 == CLASSTYPE_TI_TEMPLATE (arg)))
16822 /* Perhaps PARM is something like S<U> and ARG is S<int>.
16823 Then, we should unify `int' and `U'. */
16826 /* There's no chance of unification succeeding. */
16827 return unify_type_mismatch (explain_p, parm, arg);
16829 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
16830 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE, explain_p);
16832 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
16833 return unify_type_mismatch (explain_p, parm, arg);
16834 return unify_success (explain_p);
16837 case FUNCTION_TYPE:
16839 unsigned int nargs;
16844 if (TREE_CODE (arg) != TREE_CODE (parm))
16845 return unify_type_mismatch (explain_p, parm, arg);
16847 /* CV qualifications for methods can never be deduced, they must
16848 match exactly. We need to check them explicitly here,
16849 because type_unification_real treats them as any other
16850 cv-qualified parameter. */
16851 if (TREE_CODE (parm) == METHOD_TYPE
16852 && (!check_cv_quals_for_unify
16854 class_of_this_parm (arg),
16855 class_of_this_parm (parm))))
16856 return unify_cv_qual_mismatch (explain_p, parm, arg);
16858 RECUR_AND_CHECK_FAILURE (tparms, targs, TREE_TYPE (parm),
16859 TREE_TYPE (arg), UNIFY_ALLOW_NONE, explain_p);
16861 nargs = list_length (TYPE_ARG_TYPES (arg));
16862 args = XALLOCAVEC (tree, nargs);
16863 for (a = TYPE_ARG_TYPES (arg), i = 0;
16864 a != NULL_TREE && a != void_list_node;
16865 a = TREE_CHAIN (a), ++i)
16866 args[i] = TREE_VALUE (a);
16869 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
16870 args, nargs, 1, DEDUCE_EXACT,
16871 LOOKUP_NORMAL, explain_p);
16875 /* Unify a pointer to member with a pointer to member function, which
16876 deduces the type of the member as a function type. */
16877 if (TYPE_PTRMEMFUNC_P (arg))
16882 /* Check top-level cv qualifiers */
16883 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
16884 return unify_cv_qual_mismatch (explain_p, parm, arg);
16886 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16887 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg),
16888 UNIFY_ALLOW_NONE, explain_p);
16890 /* Determine the type of the function we are unifying against. */
16891 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
16893 build_function_type (TREE_TYPE (method_type),
16894 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
16896 /* Extract the cv-qualifiers of the member function from the
16897 implicit object parameter and place them on the function
16898 type to be restored later. */
16899 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type));
16900 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict, explain_p);
16903 if (TREE_CODE (arg) != OFFSET_TYPE)
16904 return unify_type_mismatch (explain_p, parm, arg);
16905 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
16906 TYPE_OFFSET_BASETYPE (arg),
16907 UNIFY_ALLOW_NONE, explain_p);
16908 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16909 strict, explain_p);
16912 if (DECL_TEMPLATE_PARM_P (parm))
16913 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict, explain_p);
16914 if (arg != integral_constant_value (parm))
16915 return unify_template_argument_mismatch (explain_p, parm, arg);
16916 return unify_success (explain_p);
16919 case TEMPLATE_DECL:
16920 /* Matched cases are handled by the ARG == PARM test above. */
16921 return unify_template_argument_mismatch (explain_p, parm, arg);
16924 /* A non-type template parameter that is a variable should be a
16925 an integral constant, in which case, it whould have been
16926 folded into its (constant) value. So we should not be getting
16927 a variable here. */
16928 gcc_unreachable ();
16930 case TYPE_ARGUMENT_PACK:
16931 case NONTYPE_ARGUMENT_PACK:
16932 return unify (tparms, targs, ARGUMENT_PACK_ARGS (parm),
16933 ARGUMENT_PACK_ARGS (arg), strict, explain_p);
16936 case DECLTYPE_TYPE:
16937 case UNDERLYING_TYPE:
16938 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
16939 or UNDERLYING_TYPE nodes. */
16940 return unify_success (explain_p);
16943 /* Unification fails if we hit an error node. */
16944 return unify_invalid (explain_p);
16947 /* An unresolved overload is a nondeduced context. */
16948 if (is_overloaded_fn (parm) || type_unknown_p (parm))
16949 return unify_success (explain_p);
16950 gcc_assert (EXPR_P (parm));
16952 /* We must be looking at an expression. This can happen with
16956 void foo(S<I>, S<I + 2>);
16958 This is a "nondeduced context":
16962 The nondeduced contexts are:
16964 --A type that is a template-id in which one or more of
16965 the template-arguments is an expression that references
16966 a template-parameter.
16968 In these cases, we assume deduction succeeded, but don't
16969 actually infer any unifications. */
16971 if (!uses_template_parms (parm)
16972 && !template_args_equal (parm, arg))
16973 return unify_expression_unequal (explain_p, parm, arg);
16975 return unify_success (explain_p);
16978 #undef RECUR_AND_CHECK_FAILURE
16980 /* Note that DECL can be defined in this translation unit, if
16984 mark_definable (tree decl)
16987 DECL_NOT_REALLY_EXTERN (decl) = 1;
16988 FOR_EACH_CLONE (clone, decl)
16989 DECL_NOT_REALLY_EXTERN (clone) = 1;
16992 /* Called if RESULT is explicitly instantiated, or is a member of an
16993 explicitly instantiated class. */
16996 mark_decl_instantiated (tree result, int extern_p)
16998 SET_DECL_EXPLICIT_INSTANTIATION (result);
17000 /* If this entity has already been written out, it's too late to
17001 make any modifications. */
17002 if (TREE_ASM_WRITTEN (result))
17005 if (TREE_CODE (result) != FUNCTION_DECL)
17006 /* The TREE_PUBLIC flag for function declarations will have been
17007 set correctly by tsubst. */
17008 TREE_PUBLIC (result) = 1;
17010 /* This might have been set by an earlier implicit instantiation. */
17011 DECL_COMDAT (result) = 0;
17014 DECL_NOT_REALLY_EXTERN (result) = 0;
17017 mark_definable (result);
17018 /* Always make artificials weak. */
17019 if (DECL_ARTIFICIAL (result) && flag_weak)
17020 comdat_linkage (result);
17021 /* For WIN32 we also want to put explicit instantiations in
17022 linkonce sections. */
17023 else if (TREE_PUBLIC (result))
17024 maybe_make_one_only (result);
17027 /* If EXTERN_P, then this function will not be emitted -- unless
17028 followed by an explicit instantiation, at which point its linkage
17029 will be adjusted. If !EXTERN_P, then this function will be
17030 emitted here. In neither circumstance do we want
17031 import_export_decl to adjust the linkage. */
17032 DECL_INTERFACE_KNOWN (result) = 1;
17035 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
17036 important template arguments. If any are missing, we check whether
17037 they're important by using error_mark_node for substituting into any
17038 args that were used for partial ordering (the ones between ARGS and END)
17039 and seeing if it bubbles up. */
17042 check_undeduced_parms (tree targs, tree args, tree end)
17044 bool found = false;
17046 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
17047 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
17050 TREE_VEC_ELT (targs, i) = error_mark_node;
17054 for (; args != end; args = TREE_CHAIN (args))
17056 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
17057 if (substed == error_mark_node)
17064 /* Given two function templates PAT1 and PAT2, return:
17066 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
17067 -1 if PAT2 is more specialized than PAT1.
17068 0 if neither is more specialized.
17070 LEN indicates the number of parameters we should consider
17071 (defaulted parameters should not be considered).
17073 The 1998 std underspecified function template partial ordering, and
17074 DR214 addresses the issue. We take pairs of arguments, one from
17075 each of the templates, and deduce them against each other. One of
17076 the templates will be more specialized if all the *other*
17077 template's arguments deduce against its arguments and at least one
17078 of its arguments *does* *not* deduce against the other template's
17079 corresponding argument. Deduction is done as for class templates.
17080 The arguments used in deduction have reference and top level cv
17081 qualifiers removed. Iff both arguments were originally reference
17082 types *and* deduction succeeds in both directions, the template
17083 with the more cv-qualified argument wins for that pairing (if
17084 neither is more cv-qualified, they both are equal). Unlike regular
17085 deduction, after all the arguments have been deduced in this way,
17086 we do *not* verify the deduced template argument values can be
17087 substituted into non-deduced contexts.
17089 The logic can be a bit confusing here, because we look at deduce1 and
17090 targs1 to see if pat2 is at least as specialized, and vice versa; if we
17091 can find template arguments for pat1 to make arg1 look like arg2, that
17092 means that arg2 is at least as specialized as arg1. */
17095 more_specialized_fn (tree pat1, tree pat2, int len)
17097 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
17098 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
17099 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
17100 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
17101 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
17102 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
17103 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
17104 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
17105 tree origs1, origs2;
17106 bool lose1 = false;
17107 bool lose2 = false;
17109 /* Remove the this parameter from non-static member functions. If
17110 one is a non-static member function and the other is not a static
17111 member function, remove the first parameter from that function
17112 also. This situation occurs for operator functions where we
17113 locate both a member function (with this pointer) and non-member
17114 operator (with explicit first operand). */
17115 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
17117 len--; /* LEN is the number of significant arguments for DECL1 */
17118 args1 = TREE_CHAIN (args1);
17119 if (!DECL_STATIC_FUNCTION_P (decl2))
17120 args2 = TREE_CHAIN (args2);
17122 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
17124 args2 = TREE_CHAIN (args2);
17125 if (!DECL_STATIC_FUNCTION_P (decl1))
17128 args1 = TREE_CHAIN (args1);
17132 /* If only one is a conversion operator, they are unordered. */
17133 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
17136 /* Consider the return type for a conversion function */
17137 if (DECL_CONV_FN_P (decl1))
17139 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
17140 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
17144 processing_template_decl++;
17150 /* Stop when an ellipsis is seen. */
17151 && args1 != NULL_TREE && args2 != NULL_TREE)
17153 tree arg1 = TREE_VALUE (args1);
17154 tree arg2 = TREE_VALUE (args2);
17155 int deduce1, deduce2;
17159 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17160 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17162 /* When both arguments are pack expansions, we need only
17163 unify the patterns themselves. */
17164 arg1 = PACK_EXPANSION_PATTERN (arg1);
17165 arg2 = PACK_EXPANSION_PATTERN (arg2);
17167 /* This is the last comparison we need to do. */
17171 if (TREE_CODE (arg1) == REFERENCE_TYPE)
17173 arg1 = TREE_TYPE (arg1);
17174 quals1 = cp_type_quals (arg1);
17177 if (TREE_CODE (arg2) == REFERENCE_TYPE)
17179 arg2 = TREE_TYPE (arg2);
17180 quals2 = cp_type_quals (arg2);
17183 if ((quals1 < 0) != (quals2 < 0))
17185 /* Only of the args is a reference, see if we should apply
17186 array/function pointer decay to it. This is not part of
17187 DR214, but is, IMHO, consistent with the deduction rules
17188 for the function call itself, and with our earlier
17189 implementation of the underspecified partial ordering
17190 rules. (nathan). */
17193 switch (TREE_CODE (arg1))
17196 arg1 = TREE_TYPE (arg1);
17198 case FUNCTION_TYPE:
17199 arg1 = build_pointer_type (arg1);
17208 switch (TREE_CODE (arg2))
17211 arg2 = TREE_TYPE (arg2);
17213 case FUNCTION_TYPE:
17214 arg2 = build_pointer_type (arg2);
17223 arg1 = TYPE_MAIN_VARIANT (arg1);
17224 arg2 = TYPE_MAIN_VARIANT (arg2);
17226 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
17228 int i, len2 = list_length (args2);
17229 tree parmvec = make_tree_vec (1);
17230 tree argvec = make_tree_vec (len2);
17233 /* Setup the parameter vector, which contains only ARG1. */
17234 TREE_VEC_ELT (parmvec, 0) = arg1;
17236 /* Setup the argument vector, which contains the remaining
17238 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
17239 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17241 deduce1 = (unify_pack_expansion (tparms1, targs1, parmvec,
17242 argvec, DEDUCE_EXACT,
17243 /*subr=*/true, /*explain_p=*/false)
17246 /* We cannot deduce in the other direction, because ARG1 is
17247 a pack expansion but ARG2 is not. */
17250 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17252 int i, len1 = list_length (args1);
17253 tree parmvec = make_tree_vec (1);
17254 tree argvec = make_tree_vec (len1);
17257 /* Setup the parameter vector, which contains only ARG1. */
17258 TREE_VEC_ELT (parmvec, 0) = arg2;
17260 /* Setup the argument vector, which contains the remaining
17262 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
17263 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17265 deduce2 = (unify_pack_expansion (tparms2, targs2, parmvec,
17266 argvec, DEDUCE_EXACT,
17267 /*subr=*/true, /*explain_p=*/false)
17270 /* We cannot deduce in the other direction, because ARG2 is
17271 a pack expansion but ARG1 is not.*/
17277 /* The normal case, where neither argument is a pack
17279 deduce1 = (unify (tparms1, targs1, arg1, arg2,
17280 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17282 deduce2 = (unify (tparms2, targs2, arg2, arg1,
17283 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17287 /* If we couldn't deduce arguments for tparms1 to make arg1 match
17288 arg2, then arg2 is not as specialized as arg1. */
17294 /* "If, for a given type, deduction succeeds in both directions
17295 (i.e., the types are identical after the transformations above)
17296 and if the type from the argument template is more cv-qualified
17297 than the type from the parameter template (as described above)
17298 that type is considered to be more specialized than the other. If
17299 neither type is more cv-qualified than the other then neither type
17300 is more specialized than the other." */
17302 if (deduce1 && deduce2
17303 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
17305 if ((quals1 & quals2) == quals2)
17307 if ((quals1 & quals2) == quals1)
17311 if (lose1 && lose2)
17312 /* We've failed to deduce something in either direction.
17313 These must be unordered. */
17316 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17317 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17318 /* We have already processed all of the arguments in our
17319 handing of the pack expansion type. */
17322 args1 = TREE_CHAIN (args1);
17323 args2 = TREE_CHAIN (args2);
17326 /* "In most cases, all template parameters must have values in order for
17327 deduction to succeed, but for partial ordering purposes a template
17328 parameter may remain without a value provided it is not used in the
17329 types being used for partial ordering."
17331 Thus, if we are missing any of the targs1 we need to substitute into
17332 origs1, then pat2 is not as specialized as pat1. This can happen when
17333 there is a nondeduced context. */
17334 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
17336 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
17339 processing_template_decl--;
17341 /* All things being equal, if the next argument is a pack expansion
17342 for one function but not for the other, prefer the
17343 non-variadic function. FIXME this is bogus; see c++/41958. */
17345 && args1 && TREE_VALUE (args1)
17346 && args2 && TREE_VALUE (args2))
17348 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
17349 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
17352 if (lose1 == lose2)
17360 /* Determine which of two partial specializations is more specialized.
17362 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
17363 to the first partial specialization. The TREE_VALUE is the
17364 innermost set of template parameters for the partial
17365 specialization. PAT2 is similar, but for the second template.
17367 Return 1 if the first partial specialization is more specialized;
17368 -1 if the second is more specialized; 0 if neither is more
17371 See [temp.class.order] for information about determining which of
17372 two templates is more specialized. */
17375 more_specialized_class (tree pat1, tree pat2)
17380 bool any_deductions = false;
17382 tmpl1 = TREE_TYPE (pat1);
17383 tmpl2 = TREE_TYPE (pat2);
17385 /* Just like what happens for functions, if we are ordering between
17386 different class template specializations, we may encounter dependent
17387 types in the arguments, and we need our dependency check functions
17388 to behave correctly. */
17389 ++processing_template_decl;
17390 targs = get_class_bindings (TREE_VALUE (pat1),
17391 CLASSTYPE_TI_ARGS (tmpl1),
17392 CLASSTYPE_TI_ARGS (tmpl2));
17396 any_deductions = true;
17399 targs = get_class_bindings (TREE_VALUE (pat2),
17400 CLASSTYPE_TI_ARGS (tmpl2),
17401 CLASSTYPE_TI_ARGS (tmpl1));
17405 any_deductions = true;
17407 --processing_template_decl;
17409 /* In the case of a tie where at least one of the class templates
17410 has a parameter pack at the end, the template with the most
17411 non-packed parameters wins. */
17414 && (template_args_variadic_p (TREE_PURPOSE (pat1))
17415 || template_args_variadic_p (TREE_PURPOSE (pat2))))
17417 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
17418 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
17419 int len1 = TREE_VEC_LENGTH (args1);
17420 int len2 = TREE_VEC_LENGTH (args2);
17422 /* We don't count the pack expansion at the end. */
17423 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
17425 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
17430 else if (len1 < len2)
17437 /* Return the template arguments that will produce the function signature
17438 DECL from the function template FN, with the explicit template
17439 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
17440 also match. Return NULL_TREE if no satisfactory arguments could be
17444 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
17446 int ntparms = DECL_NTPARMS (fn);
17447 tree targs = make_tree_vec (ntparms);
17449 tree decl_arg_types;
17451 unsigned int nargs, ix;
17454 /* Substitute the explicit template arguments into the type of DECL.
17455 The call to fn_type_unification will handle substitution into the
17457 decl_type = TREE_TYPE (decl);
17458 if (explicit_args && uses_template_parms (decl_type))
17461 tree converted_args;
17463 if (DECL_TEMPLATE_INFO (decl))
17464 tmpl = DECL_TI_TEMPLATE (decl);
17466 /* We can get here for some invalid specializations. */
17470 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17471 explicit_args, NULL_TREE,
17473 /*require_all_args=*/false,
17474 /*use_default_args=*/false);
17475 if (converted_args == error_mark_node)
17478 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
17479 if (decl_type == error_mark_node)
17483 /* Never do unification on the 'this' parameter. */
17484 decl_arg_types = skip_artificial_parms_for (decl,
17485 TYPE_ARG_TYPES (decl_type));
17487 nargs = list_length (decl_arg_types);
17488 args = XALLOCAVEC (tree, nargs);
17489 for (arg = decl_arg_types, ix = 0;
17490 arg != NULL_TREE && arg != void_list_node;
17491 arg = TREE_CHAIN (arg), ++ix)
17492 args[ix] = TREE_VALUE (arg);
17494 if (fn_type_unification (fn, explicit_args, targs,
17496 (check_rettype || DECL_CONV_FN_P (fn)
17497 ? TREE_TYPE (decl_type) : NULL_TREE),
17498 DEDUCE_EXACT, LOOKUP_NORMAL, /*explain_p=*/false))
17504 /* Return the innermost template arguments that, when applied to a
17505 template specialization whose innermost template parameters are
17506 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
17509 For example, suppose we have:
17511 template <class T, class U> struct S {};
17512 template <class T> struct S<T*, int> {};
17514 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
17515 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
17516 int}. The resulting vector will be {double}, indicating that `T'
17517 is bound to `double'. */
17520 get_class_bindings (tree tparms, tree spec_args, tree args)
17522 int i, ntparms = TREE_VEC_LENGTH (tparms);
17524 tree innermost_deduced_args;
17526 innermost_deduced_args = make_tree_vec (ntparms);
17527 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17529 deduced_args = copy_node (args);
17530 SET_TMPL_ARGS_LEVEL (deduced_args,
17531 TMPL_ARGS_DEPTH (deduced_args),
17532 innermost_deduced_args);
17535 deduced_args = innermost_deduced_args;
17537 if (unify (tparms, deduced_args,
17538 INNERMOST_TEMPLATE_ARGS (spec_args),
17539 INNERMOST_TEMPLATE_ARGS (args),
17540 UNIFY_ALLOW_NONE, /*explain_p=*/false))
17543 for (i = 0; i < ntparms; ++i)
17544 if (! TREE_VEC_ELT (innermost_deduced_args, i))
17547 /* Verify that nondeduced template arguments agree with the type
17548 obtained from argument deduction.
17552 struct A { typedef int X; };
17553 template <class T, class U> struct C {};
17554 template <class T> struct C<T, typename T::X> {};
17556 Then with the instantiation `C<A, int>', we can deduce that
17557 `T' is `A' but unify () does not check whether `typename T::X'
17559 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
17560 if (spec_args == error_mark_node
17561 /* We only need to check the innermost arguments; the other
17562 arguments will always agree. */
17563 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
17564 INNERMOST_TEMPLATE_ARGS (args)))
17567 /* Now that we have bindings for all of the template arguments,
17568 ensure that the arguments deduced for the template template
17569 parameters have compatible template parameter lists. See the use
17570 of template_template_parm_bindings_ok_p in fn_type_unification
17571 for more information. */
17572 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
17575 return deduced_args;
17578 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
17579 Return the TREE_LIST node with the most specialized template, if
17580 any. If there is no most specialized template, the error_mark_node
17583 Note that this function does not look at, or modify, the
17584 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
17585 returned is one of the elements of INSTANTIATIONS, callers may
17586 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
17587 and retrieve it from the value returned. */
17590 most_specialized_instantiation (tree templates)
17594 ++processing_template_decl;
17597 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
17601 if (get_bindings (TREE_VALUE (champ),
17602 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17603 NULL_TREE, /*check_ret=*/true))
17606 if (get_bindings (TREE_VALUE (fn),
17607 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17608 NULL_TREE, /*check_ret=*/true))
17615 /* Equally specialized, move to next function. If there
17616 is no next function, nothing's most specialized. */
17617 fn = TREE_CHAIN (fn);
17625 /* Now verify that champ is better than everything earlier in the
17626 instantiation list. */
17627 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
17628 if (get_bindings (TREE_VALUE (champ),
17629 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17630 NULL_TREE, /*check_ret=*/true)
17631 || !get_bindings (TREE_VALUE (fn),
17632 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17633 NULL_TREE, /*check_ret=*/true))
17639 processing_template_decl--;
17642 return error_mark_node;
17647 /* If DECL is a specialization of some template, return the most
17648 general such template. Otherwise, returns NULL_TREE.
17650 For example, given:
17652 template <class T> struct S { template <class U> void f(U); };
17654 if TMPL is `template <class U> void S<int>::f(U)' this will return
17655 the full template. This function will not trace past partial
17656 specializations, however. For example, given in addition:
17658 template <class T> struct S<T*> { template <class U> void f(U); };
17660 if TMPL is `template <class U> void S<int*>::f(U)' this will return
17661 `template <class T> template <class U> S<T*>::f(U)'. */
17664 most_general_template (tree decl)
17666 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
17667 an immediate specialization. */
17668 if (TREE_CODE (decl) == FUNCTION_DECL)
17670 if (DECL_TEMPLATE_INFO (decl)) {
17671 decl = DECL_TI_TEMPLATE (decl);
17673 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
17674 template friend. */
17675 if (TREE_CODE (decl) != TEMPLATE_DECL)
17681 /* Look for more and more general templates. */
17682 while (DECL_TEMPLATE_INFO (decl))
17684 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
17685 (See cp-tree.h for details.) */
17686 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
17689 if (CLASS_TYPE_P (TREE_TYPE (decl))
17690 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
17693 /* Stop if we run into an explicitly specialized class template. */
17694 if (!DECL_NAMESPACE_SCOPE_P (decl)
17695 && DECL_CONTEXT (decl)
17696 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
17699 decl = DECL_TI_TEMPLATE (decl);
17705 /* Return the most specialized of the class template partial
17706 specializations of TMPL which can produce TYPE, a specialization of
17707 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
17708 a _TYPE node corresponding to the partial specialization, while the
17709 TREE_PURPOSE is the set of template arguments that must be
17710 substituted into the TREE_TYPE in order to generate TYPE.
17712 If the choice of partial specialization is ambiguous, a diagnostic
17713 is issued, and the error_mark_node is returned. If there are no
17714 partial specializations of TMPL matching TYPE, then NULL_TREE is
17718 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
17720 tree list = NULL_TREE;
17726 tree outer_args = NULL_TREE;
17728 tmpl = most_general_template (tmpl);
17729 args = CLASSTYPE_TI_ARGS (type);
17731 /* For determining which partial specialization to use, only the
17732 innermost args are interesting. */
17733 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17735 outer_args = strip_innermost_template_args (args, 1);
17736 args = INNERMOST_TEMPLATE_ARGS (args);
17739 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
17741 tree partial_spec_args;
17743 tree parms = TREE_VALUE (t);
17745 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
17747 ++processing_template_decl;
17753 /* Discard the outer levels of args, and then substitute in the
17754 template args from the enclosing class. */
17755 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
17756 partial_spec_args = tsubst_template_args
17757 (partial_spec_args, outer_args, tf_none, NULL_TREE);
17759 /* PARMS already refers to just the innermost parms, but the
17760 template parms in partial_spec_args had their levels lowered
17761 by tsubst, so we need to do the same for the parm list. We
17762 can't just tsubst the TREE_VEC itself, as tsubst wants to
17763 treat a TREE_VEC as an argument vector. */
17764 parms = copy_node (parms);
17765 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
17766 TREE_VEC_ELT (parms, i) =
17767 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
17771 partial_spec_args =
17772 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17773 add_to_template_args (outer_args,
17774 partial_spec_args),
17776 /*require_all_args=*/true,
17777 /*use_default_args=*/true);
17779 --processing_template_decl;
17781 if (partial_spec_args == error_mark_node)
17782 return error_mark_node;
17784 spec_args = get_class_bindings (parms,
17790 spec_args = add_to_template_args (outer_args, spec_args);
17791 list = tree_cons (spec_args, TREE_VALUE (t), list);
17792 TREE_TYPE (list) = TREE_TYPE (t);
17799 ambiguous_p = false;
17802 t = TREE_CHAIN (t);
17803 for (; t; t = TREE_CHAIN (t))
17805 fate = more_specialized_class (champ, t);
17812 t = TREE_CHAIN (t);
17815 ambiguous_p = true;
17824 for (t = list; t && t != champ; t = TREE_CHAIN (t))
17826 fate = more_specialized_class (champ, t);
17829 ambiguous_p = true;
17837 char *spaces = NULL;
17838 if (!(complain & tf_error))
17839 return error_mark_node;
17840 error ("ambiguous class template instantiation for %q#T", type);
17841 str = ngettext ("candidate is:", "candidates are:", list_length (list));
17842 for (t = list; t; t = TREE_CHAIN (t))
17844 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
17845 spaces = spaces ? spaces : get_spaces (str);
17848 return error_mark_node;
17854 /* Explicitly instantiate DECL. */
17857 do_decl_instantiation (tree decl, tree storage)
17859 tree result = NULL_TREE;
17862 if (!decl || decl == error_mark_node)
17863 /* An error occurred, for which grokdeclarator has already issued
17864 an appropriate message. */
17866 else if (! DECL_LANG_SPECIFIC (decl))
17868 error ("explicit instantiation of non-template %q#D", decl);
17871 else if (TREE_CODE (decl) == VAR_DECL)
17873 /* There is an asymmetry here in the way VAR_DECLs and
17874 FUNCTION_DECLs are handled by grokdeclarator. In the case of
17875 the latter, the DECL we get back will be marked as a
17876 template instantiation, and the appropriate
17877 DECL_TEMPLATE_INFO will be set up. This does not happen for
17878 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
17879 should handle VAR_DECLs as it currently handles
17881 if (!DECL_CLASS_SCOPE_P (decl))
17883 error ("%qD is not a static data member of a class template", decl);
17886 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
17887 if (!result || TREE_CODE (result) != VAR_DECL)
17889 error ("no matching template for %qD found", decl);
17892 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
17894 error ("type %qT for explicit instantiation %qD does not match "
17895 "declared type %qT", TREE_TYPE (result), decl,
17900 else if (TREE_CODE (decl) != FUNCTION_DECL)
17902 error ("explicit instantiation of %q#D", decl);
17908 /* Check for various error cases. Note that if the explicit
17909 instantiation is valid the RESULT will currently be marked as an
17910 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
17911 until we get here. */
17913 if (DECL_TEMPLATE_SPECIALIZATION (result))
17915 /* DR 259 [temp.spec].
17917 Both an explicit instantiation and a declaration of an explicit
17918 specialization shall not appear in a program unless the explicit
17919 instantiation follows a declaration of the explicit specialization.
17921 For a given set of template parameters, if an explicit
17922 instantiation of a template appears after a declaration of an
17923 explicit specialization for that template, the explicit
17924 instantiation has no effect. */
17927 else if (DECL_EXPLICIT_INSTANTIATION (result))
17931 No program shall explicitly instantiate any template more
17934 We check DECL_NOT_REALLY_EXTERN so as not to complain when
17935 the first instantiation was `extern' and the second is not,
17936 and EXTERN_P for the opposite case. */
17937 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
17938 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
17939 /* If an "extern" explicit instantiation follows an ordinary
17940 explicit instantiation, the template is instantiated. */
17944 else if (!DECL_IMPLICIT_INSTANTIATION (result))
17946 error ("no matching template for %qD found", result);
17949 else if (!DECL_TEMPLATE_INFO (result))
17951 permerror (input_location, "explicit instantiation of non-template %q#D", result);
17955 if (storage == NULL_TREE)
17957 else if (storage == ridpointers[(int) RID_EXTERN])
17959 if (!in_system_header && (cxx_dialect == cxx98))
17960 pedwarn (input_location, OPT_pedantic,
17961 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
17966 error ("storage class %qD applied to template instantiation", storage);
17968 check_explicit_instantiation_namespace (result);
17969 mark_decl_instantiated (result, extern_p);
17971 instantiate_decl (result, /*defer_ok=*/1,
17972 /*expl_inst_class_mem_p=*/false);
17976 mark_class_instantiated (tree t, int extern_p)
17978 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
17979 SET_CLASSTYPE_INTERFACE_KNOWN (t);
17980 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
17981 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
17984 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
17985 rest_of_type_compilation (t, 1);
17989 /* Called from do_type_instantiation through binding_table_foreach to
17990 do recursive instantiation for the type bound in ENTRY. */
17992 bt_instantiate_type_proc (binding_entry entry, void *data)
17994 tree storage = *(tree *) data;
17996 if (MAYBE_CLASS_TYPE_P (entry->type)
17997 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
17998 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
18001 /* Called from do_type_instantiation to instantiate a member
18002 (a member function or a static member variable) of an
18003 explicitly instantiated class template. */
18005 instantiate_class_member (tree decl, int extern_p)
18007 mark_decl_instantiated (decl, extern_p);
18009 instantiate_decl (decl, /*defer_ok=*/1,
18010 /*expl_inst_class_mem_p=*/true);
18013 /* Perform an explicit instantiation of template class T. STORAGE, if
18014 non-null, is the RID for extern, inline or static. COMPLAIN is
18015 nonzero if this is called from the parser, zero if called recursively,
18016 since the standard is unclear (as detailed below). */
18019 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
18024 int previous_instantiation_extern_p = 0;
18026 if (TREE_CODE (t) == TYPE_DECL)
18029 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
18032 (TYPE_TEMPLATE_INFO (t)) ? TYPE_TI_TEMPLATE (t) : NULL;
18034 error ("explicit instantiation of non-class template %qD", tmpl);
18036 error ("explicit instantiation of non-template type %qT", t);
18042 if (!COMPLETE_TYPE_P (t))
18044 if (complain & tf_error)
18045 error ("explicit instantiation of %q#T before definition of template",
18050 if (storage != NULL_TREE)
18052 if (!in_system_header)
18054 if (storage == ridpointers[(int) RID_EXTERN])
18056 if (cxx_dialect == cxx98)
18057 pedwarn (input_location, OPT_pedantic,
18058 "ISO C++ 1998 forbids the use of %<extern%> on "
18059 "explicit instantiations");
18062 pedwarn (input_location, OPT_pedantic,
18063 "ISO C++ forbids the use of %qE"
18064 " on explicit instantiations", storage);
18067 if (storage == ridpointers[(int) RID_INLINE])
18069 else if (storage == ridpointers[(int) RID_EXTERN])
18071 else if (storage == ridpointers[(int) RID_STATIC])
18075 error ("storage class %qD applied to template instantiation",
18081 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
18083 /* DR 259 [temp.spec].
18085 Both an explicit instantiation and a declaration of an explicit
18086 specialization shall not appear in a program unless the explicit
18087 instantiation follows a declaration of the explicit specialization.
18089 For a given set of template parameters, if an explicit
18090 instantiation of a template appears after a declaration of an
18091 explicit specialization for that template, the explicit
18092 instantiation has no effect. */
18095 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
18099 No program shall explicitly instantiate any template more
18102 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
18103 instantiation was `extern'. If EXTERN_P then the second is.
18104 These cases are OK. */
18105 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
18107 if (!previous_instantiation_extern_p && !extern_p
18108 && (complain & tf_error))
18109 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
18111 /* If we've already instantiated the template, just return now. */
18112 if (!CLASSTYPE_INTERFACE_ONLY (t))
18116 check_explicit_instantiation_namespace (TYPE_NAME (t));
18117 mark_class_instantiated (t, extern_p);
18125 /* In contrast to implicit instantiation, where only the
18126 declarations, and not the definitions, of members are
18127 instantiated, we have here:
18131 The explicit instantiation of a class template specialization
18132 implies the instantiation of all of its members not
18133 previously explicitly specialized in the translation unit
18134 containing the explicit instantiation.
18136 Of course, we can't instantiate member template classes, since
18137 we don't have any arguments for them. Note that the standard
18138 is unclear on whether the instantiation of the members are
18139 *explicit* instantiations or not. However, the most natural
18140 interpretation is that it should be an explicit instantiation. */
18143 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
18144 if (TREE_CODE (tmp) == FUNCTION_DECL
18145 && DECL_TEMPLATE_INSTANTIATION (tmp))
18146 instantiate_class_member (tmp, extern_p);
18148 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
18149 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
18150 instantiate_class_member (tmp, extern_p);
18152 if (CLASSTYPE_NESTED_UTDS (t))
18153 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
18154 bt_instantiate_type_proc, &storage);
18158 /* Given a function DECL, which is a specialization of TMPL, modify
18159 DECL to be a re-instantiation of TMPL with the same template
18160 arguments. TMPL should be the template into which tsubst'ing
18161 should occur for DECL, not the most general template.
18163 One reason for doing this is a scenario like this:
18166 void f(const T&, int i);
18168 void g() { f(3, 7); }
18171 void f(const T& t, const int i) { }
18173 Note that when the template is first instantiated, with
18174 instantiate_template, the resulting DECL will have no name for the
18175 first parameter, and the wrong type for the second. So, when we go
18176 to instantiate the DECL, we regenerate it. */
18179 regenerate_decl_from_template (tree decl, tree tmpl)
18181 /* The arguments used to instantiate DECL, from the most general
18186 args = DECL_TI_ARGS (decl);
18187 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
18189 /* Make sure that we can see identifiers, and compute access
18191 push_access_scope (decl);
18193 if (TREE_CODE (decl) == FUNCTION_DECL)
18201 args_depth = TMPL_ARGS_DEPTH (args);
18202 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
18203 if (args_depth > parms_depth)
18204 args = get_innermost_template_args (args, parms_depth);
18206 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
18207 args, tf_error, NULL_TREE,
18208 /*defer_ok*/false);
18209 if (specs && specs != error_mark_node)
18210 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
18213 /* Merge parameter declarations. */
18214 decl_parm = skip_artificial_parms_for (decl,
18215 DECL_ARGUMENTS (decl));
18217 = skip_artificial_parms_for (code_pattern,
18218 DECL_ARGUMENTS (code_pattern));
18219 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
18224 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18225 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
18226 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
18228 parm_type = type_decays_to (parm_type);
18229 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18230 TREE_TYPE (decl_parm) = parm_type;
18231 attributes = DECL_ATTRIBUTES (pattern_parm);
18232 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18234 DECL_ATTRIBUTES (decl_parm) = attributes;
18235 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18237 decl_parm = DECL_CHAIN (decl_parm);
18238 pattern_parm = DECL_CHAIN (pattern_parm);
18240 /* Merge any parameters that match with the function parameter
18242 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
18245 tree expanded_types;
18246 /* Expand the TYPE_PACK_EXPANSION that provides the types for
18247 the parameters in this function parameter pack. */
18248 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
18249 args, tf_error, NULL_TREE);
18250 len = TREE_VEC_LENGTH (expanded_types);
18251 for (i = 0; i < len; i++)
18256 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18257 /* Rename the parameter to include the index. */
18258 DECL_NAME (decl_parm) =
18259 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
18260 parm_type = TREE_VEC_ELT (expanded_types, i);
18261 parm_type = type_decays_to (parm_type);
18262 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18263 TREE_TYPE (decl_parm) = parm_type;
18264 attributes = DECL_ATTRIBUTES (pattern_parm);
18265 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18267 DECL_ATTRIBUTES (decl_parm) = attributes;
18268 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18270 decl_parm = DECL_CHAIN (decl_parm);
18273 /* Merge additional specifiers from the CODE_PATTERN. */
18274 if (DECL_DECLARED_INLINE_P (code_pattern)
18275 && !DECL_DECLARED_INLINE_P (decl))
18276 DECL_DECLARED_INLINE_P (decl) = 1;
18278 else if (TREE_CODE (decl) == VAR_DECL)
18280 DECL_INITIAL (decl) =
18281 tsubst_expr (DECL_INITIAL (code_pattern), args,
18282 tf_error, DECL_TI_TEMPLATE (decl),
18283 /*integral_constant_expression_p=*/false);
18284 if (VAR_HAD_UNKNOWN_BOUND (decl))
18285 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
18286 tf_error, DECL_TI_TEMPLATE (decl));
18289 gcc_unreachable ();
18291 pop_access_scope (decl);
18294 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
18295 substituted to get DECL. */
18298 template_for_substitution (tree decl)
18300 tree tmpl = DECL_TI_TEMPLATE (decl);
18302 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
18303 for the instantiation. This is not always the most general
18304 template. Consider, for example:
18307 struct S { template <class U> void f();
18308 template <> void f<int>(); };
18310 and an instantiation of S<double>::f<int>. We want TD to be the
18311 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
18312 while (/* An instantiation cannot have a definition, so we need a
18313 more general template. */
18314 DECL_TEMPLATE_INSTANTIATION (tmpl)
18315 /* We must also deal with friend templates. Given:
18317 template <class T> struct S {
18318 template <class U> friend void f() {};
18321 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
18322 so far as the language is concerned, but that's still
18323 where we get the pattern for the instantiation from. On
18324 other hand, if the definition comes outside the class, say:
18326 template <class T> struct S {
18327 template <class U> friend void f();
18329 template <class U> friend void f() {}
18331 we don't need to look any further. That's what the check for
18332 DECL_INITIAL is for. */
18333 || (TREE_CODE (decl) == FUNCTION_DECL
18334 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
18335 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
18337 /* The present template, TD, should not be a definition. If it
18338 were a definition, we should be using it! Note that we
18339 cannot restructure the loop to just keep going until we find
18340 a template with a definition, since that might go too far if
18341 a specialization was declared, but not defined. */
18342 gcc_assert (TREE_CODE (decl) != VAR_DECL
18343 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
18345 /* Fetch the more general template. */
18346 tmpl = DECL_TI_TEMPLATE (tmpl);
18352 /* Returns true if we need to instantiate this template instance even if we
18353 know we aren't going to emit it.. */
18356 always_instantiate_p (tree decl)
18358 /* We always instantiate inline functions so that we can inline them. An
18359 explicit instantiation declaration prohibits implicit instantiation of
18360 non-inline functions. With high levels of optimization, we would
18361 normally inline non-inline functions -- but we're not allowed to do
18362 that for "extern template" functions. Therefore, we check
18363 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
18364 return ((TREE_CODE (decl) == FUNCTION_DECL
18365 && DECL_DECLARED_INLINE_P (decl))
18366 /* And we need to instantiate static data members so that
18367 their initializers are available in integral constant
18369 || (TREE_CODE (decl) == VAR_DECL
18370 && decl_maybe_constant_var_p (decl)));
18373 /* If FN has a noexcept-specifier that hasn't been instantiated yet,
18374 instantiate it now, modifying TREE_TYPE (fn). */
18377 maybe_instantiate_noexcept (tree fn)
18379 tree fntype, spec, noex, clone;
18381 if (DECL_CLONED_FUNCTION_P (fn))
18382 fn = DECL_CLONED_FUNCTION (fn);
18383 fntype = TREE_TYPE (fn);
18384 spec = TYPE_RAISES_EXCEPTIONS (fntype);
18386 if (!DEFERRED_NOEXCEPT_SPEC_P (spec))
18389 noex = TREE_PURPOSE (spec);
18391 if (TREE_CODE (noex) == DEFERRED_NOEXCEPT)
18393 if (push_tinst_level (fn))
18395 push_access_scope (fn);
18396 input_location = DECL_SOURCE_LOCATION (fn);
18397 noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex),
18398 DEFERRED_NOEXCEPT_ARGS (noex),
18399 tf_warning_or_error, fn,
18400 /*function_p=*/false,
18401 /*integral_constant_expression_p=*/true);
18402 pop_access_scope (fn);
18403 pop_tinst_level ();
18404 spec = build_noexcept_spec (noex, tf_warning_or_error);
18405 if (spec == error_mark_node)
18406 spec = noexcept_false_spec;
18409 spec = noexcept_false_spec;
18413 /* This is an implicitly declared function, so NOEX is a list of
18414 other functions to evaluate and merge. */
18416 spec = noexcept_true_spec;
18417 for (elt = noex; elt; elt = OVL_NEXT (elt))
18419 tree fn = OVL_CURRENT (elt);
18421 maybe_instantiate_noexcept (fn);
18422 subspec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn));
18423 spec = merge_exception_specifiers (spec, subspec, NULL_TREE);
18427 TREE_TYPE (fn) = build_exception_variant (fntype, spec);
18429 FOR_EACH_CLONE (clone, fn)
18431 if (TREE_TYPE (clone) == fntype)
18432 TREE_TYPE (clone) = TREE_TYPE (fn);
18434 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone), spec);
18438 /* Produce the definition of D, a _DECL generated from a template. If
18439 DEFER_OK is nonzero, then we don't have to actually do the
18440 instantiation now; we just have to do it sometime. Normally it is
18441 an error if this is an explicit instantiation but D is undefined.
18442 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
18443 explicitly instantiated class template. */
18446 instantiate_decl (tree d, int defer_ok,
18447 bool expl_inst_class_mem_p)
18449 tree tmpl = DECL_TI_TEMPLATE (d);
18456 bool pattern_defined;
18458 location_t saved_loc = input_location;
18461 /* This function should only be used to instantiate templates for
18462 functions and static member variables. */
18463 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
18464 || TREE_CODE (d) == VAR_DECL);
18466 /* Variables are never deferred; if instantiation is required, they
18467 are instantiated right away. That allows for better code in the
18468 case that an expression refers to the value of the variable --
18469 if the variable has a constant value the referring expression can
18470 take advantage of that fact. */
18471 if (TREE_CODE (d) == VAR_DECL
18472 || DECL_DECLARED_CONSTEXPR_P (d))
18475 /* Don't instantiate cloned functions. Instead, instantiate the
18476 functions they cloned. */
18477 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
18478 d = DECL_CLONED_FUNCTION (d);
18480 if (DECL_TEMPLATE_INSTANTIATED (d)
18481 || (TREE_CODE (d) == FUNCTION_DECL
18482 && DECL_DEFAULTED_FN (d) && DECL_INITIAL (d))
18483 || DECL_TEMPLATE_SPECIALIZATION (d))
18484 /* D has already been instantiated or explicitly specialized, so
18485 there's nothing for us to do here.
18487 It might seem reasonable to check whether or not D is an explicit
18488 instantiation, and, if so, stop here. But when an explicit
18489 instantiation is deferred until the end of the compilation,
18490 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
18491 the instantiation. */
18494 /* Check to see whether we know that this template will be
18495 instantiated in some other file, as with "extern template"
18497 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
18499 /* In general, we do not instantiate such templates. */
18500 if (external_p && !always_instantiate_p (d))
18503 gen_tmpl = most_general_template (tmpl);
18504 gen_args = DECL_TI_ARGS (d);
18506 if (tmpl != gen_tmpl)
18507 /* We should already have the extra args. */
18508 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
18509 == TMPL_ARGS_DEPTH (gen_args));
18510 /* And what's in the hash table should match D. */
18511 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
18512 || spec == NULL_TREE);
18514 /* This needs to happen before any tsubsting. */
18515 if (! push_tinst_level (d))
18518 timevar_push (TV_TEMPLATE_INST);
18520 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
18521 for the instantiation. */
18522 td = template_for_substitution (d);
18523 code_pattern = DECL_TEMPLATE_RESULT (td);
18525 /* We should never be trying to instantiate a member of a class
18526 template or partial specialization. */
18527 gcc_assert (d != code_pattern);
18529 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
18530 || DECL_TEMPLATE_SPECIALIZATION (td))
18531 /* In the case of a friend template whose definition is provided
18532 outside the class, we may have too many arguments. Drop the
18533 ones we don't need. The same is true for specializations. */
18534 args = get_innermost_template_args
18535 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
18539 if (TREE_CODE (d) == FUNCTION_DECL)
18540 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE
18541 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern));
18543 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
18545 /* We may be in the middle of deferred access check. Disable it now. */
18546 push_deferring_access_checks (dk_no_deferred);
18548 /* Unless an explicit instantiation directive has already determined
18549 the linkage of D, remember that a definition is available for
18551 if (pattern_defined
18552 && !DECL_INTERFACE_KNOWN (d)
18553 && !DECL_NOT_REALLY_EXTERN (d))
18554 mark_definable (d);
18556 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
18557 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
18558 input_location = DECL_SOURCE_LOCATION (d);
18560 /* If D is a member of an explicitly instantiated class template,
18561 and no definition is available, treat it like an implicit
18563 if (!pattern_defined && expl_inst_class_mem_p
18564 && DECL_EXPLICIT_INSTANTIATION (d))
18566 /* Leave linkage flags alone on instantiations with anonymous
18568 if (TREE_PUBLIC (d))
18570 DECL_NOT_REALLY_EXTERN (d) = 0;
18571 DECL_INTERFACE_KNOWN (d) = 0;
18573 SET_DECL_IMPLICIT_INSTANTIATION (d);
18576 if (TREE_CODE (d) == FUNCTION_DECL)
18577 maybe_instantiate_noexcept (d);
18579 /* Recheck the substitutions to obtain any warning messages
18580 about ignoring cv qualifiers. Don't do this for artificial decls,
18581 as it breaks the context-sensitive substitution for lambda op(). */
18582 if (!defer_ok && !DECL_ARTIFICIAL (d))
18584 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
18585 tree type = TREE_TYPE (gen);
18587 /* Make sure that we can see identifiers, and compute access
18588 correctly. D is already the target FUNCTION_DECL with the
18590 push_access_scope (d);
18592 if (TREE_CODE (gen) == FUNCTION_DECL)
18594 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
18595 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
18596 d, /*defer_ok*/true);
18597 /* Don't simply tsubst the function type, as that will give
18598 duplicate warnings about poor parameter qualifications.
18599 The function arguments are the same as the decl_arguments
18600 without the top level cv qualifiers. */
18601 type = TREE_TYPE (type);
18603 tsubst (type, gen_args, tf_warning_or_error, d);
18605 pop_access_scope (d);
18608 /* Defer all other templates, unless we have been explicitly
18609 forbidden from doing so. */
18610 if (/* If there is no definition, we cannot instantiate the
18613 /* If it's OK to postpone instantiation, do so. */
18615 /* If this is a static data member that will be defined
18616 elsewhere, we don't want to instantiate the entire data
18617 member, but we do want to instantiate the initializer so that
18618 we can substitute that elsewhere. */
18619 || (external_p && TREE_CODE (d) == VAR_DECL))
18621 /* The definition of the static data member is now required so
18622 we must substitute the initializer. */
18623 if (TREE_CODE (d) == VAR_DECL
18624 && !DECL_INITIAL (d)
18625 && DECL_INITIAL (code_pattern))
18629 bool const_init = false;
18631 ns = decl_namespace_context (d);
18632 push_nested_namespace (ns);
18633 push_nested_class (DECL_CONTEXT (d));
18634 init = tsubst_expr (DECL_INITIAL (code_pattern),
18636 tf_warning_or_error, NULL_TREE,
18637 /*integral_constant_expression_p=*/false);
18638 /* Make sure the initializer is still constant, in case of
18639 circular dependency (template/instantiate6.C). */
18641 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18642 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
18643 /*asmspec_tree=*/NULL_TREE,
18644 LOOKUP_ONLYCONVERTING);
18645 pop_nested_class ();
18646 pop_nested_namespace (ns);
18649 /* We restore the source position here because it's used by
18650 add_pending_template. */
18651 input_location = saved_loc;
18653 if (at_eof && !pattern_defined
18654 && DECL_EXPLICIT_INSTANTIATION (d)
18655 && DECL_NOT_REALLY_EXTERN (d))
18658 The definition of a non-exported function template, a
18659 non-exported member function template, or a non-exported
18660 member function or static data member of a class template
18661 shall be present in every translation unit in which it is
18662 explicitly instantiated. */
18663 permerror (input_location, "explicit instantiation of %qD "
18664 "but no definition available", d);
18666 /* If we're in unevaluated context, we just wanted to get the
18667 constant value; this isn't an odr use, so don't queue
18668 a full instantiation. */
18669 if (cp_unevaluated_operand != 0)
18671 /* ??? Historically, we have instantiated inline functions, even
18672 when marked as "extern template". */
18673 if (!(external_p && TREE_CODE (d) == VAR_DECL))
18674 add_pending_template (d);
18677 /* Tell the repository that D is available in this translation unit
18678 -- and see if it is supposed to be instantiated here. */
18679 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
18681 /* In a PCH file, despite the fact that the repository hasn't
18682 requested instantiation in the PCH it is still possible that
18683 an instantiation will be required in a file that includes the
18686 add_pending_template (d);
18687 /* Instantiate inline functions so that the inliner can do its
18688 job, even though we'll not be emitting a copy of this
18690 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
18694 need_push = !cfun || !global_bindings_p ();
18696 push_to_top_level ();
18698 /* Mark D as instantiated so that recursive calls to
18699 instantiate_decl do not try to instantiate it again. */
18700 DECL_TEMPLATE_INSTANTIATED (d) = 1;
18702 /* Regenerate the declaration in case the template has been modified
18703 by a subsequent redeclaration. */
18704 regenerate_decl_from_template (d, td);
18706 /* We already set the file and line above. Reset them now in case
18707 they changed as a result of calling regenerate_decl_from_template. */
18708 input_location = DECL_SOURCE_LOCATION (d);
18710 if (TREE_CODE (d) == VAR_DECL)
18713 bool const_init = false;
18715 /* Clear out DECL_RTL; whatever was there before may not be right
18716 since we've reset the type of the declaration. */
18717 SET_DECL_RTL (d, NULL);
18718 DECL_IN_AGGR_P (d) = 0;
18720 /* The initializer is placed in DECL_INITIAL by
18721 regenerate_decl_from_template so we don't need to
18722 push/pop_access_scope again here. Pull it out so that
18723 cp_finish_decl can process it. */
18724 init = DECL_INITIAL (d);
18725 DECL_INITIAL (d) = NULL_TREE;
18726 DECL_INITIALIZED_P (d) = 0;
18728 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
18729 initializer. That function will defer actual emission until
18730 we have a chance to determine linkage. */
18731 DECL_EXTERNAL (d) = 0;
18733 /* Enter the scope of D so that access-checking works correctly. */
18734 push_nested_class (DECL_CONTEXT (d));
18735 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18736 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
18737 pop_nested_class ();
18739 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern))
18740 synthesize_method (d);
18741 else if (TREE_CODE (d) == FUNCTION_DECL)
18743 htab_t saved_local_specializations;
18748 /* Save away the current list, in case we are instantiating one
18749 template from within the body of another. */
18750 saved_local_specializations = local_specializations;
18752 /* Set up the list of local specializations. */
18753 local_specializations = htab_create (37,
18754 hash_local_specialization,
18755 eq_local_specializations,
18758 /* Set up context. */
18759 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
18761 /* Create substitution entries for the parameters. */
18762 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
18763 tmpl_parm = DECL_ARGUMENTS (subst_decl);
18764 spec_parm = DECL_ARGUMENTS (d);
18765 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
18767 register_local_specialization (spec_parm, tmpl_parm);
18768 spec_parm = skip_artificial_parms_for (d, spec_parm);
18769 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
18771 for (; tmpl_parm; tmpl_parm = DECL_CHAIN (tmpl_parm))
18773 if (!FUNCTION_PARAMETER_PACK_P (tmpl_parm))
18775 register_local_specialization (spec_parm, tmpl_parm);
18776 spec_parm = DECL_CHAIN (spec_parm);
18780 /* Register the (value) argument pack as a specialization of
18781 TMPL_PARM, then move on. */
18782 tree argpack = extract_fnparm_pack (tmpl_parm, &spec_parm);
18783 register_local_specialization (argpack, tmpl_parm);
18786 gcc_assert (!spec_parm);
18788 /* Substitute into the body of the function. */
18789 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
18790 tf_warning_or_error, tmpl,
18791 /*integral_constant_expression_p=*/false);
18793 /* Set the current input_location to the end of the function
18794 so that finish_function knows where we are. */
18795 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
18797 /* We don't need the local specializations any more. */
18798 htab_delete (local_specializations);
18799 local_specializations = saved_local_specializations;
18801 /* Finish the function. */
18802 d = finish_function (0);
18803 expand_or_defer_fn (d);
18806 /* We're not deferring instantiation any more. */
18807 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
18810 pop_from_top_level ();
18813 input_location = saved_loc;
18814 pop_deferring_access_checks ();
18815 pop_tinst_level ();
18817 timevar_pop (TV_TEMPLATE_INST);
18822 /* Run through the list of templates that we wish we could
18823 instantiate, and instantiate any we can. RETRIES is the
18824 number of times we retry pending template instantiation. */
18827 instantiate_pending_templates (int retries)
18830 location_t saved_loc = input_location;
18832 /* Instantiating templates may trigger vtable generation. This in turn
18833 may require further template instantiations. We place a limit here
18834 to avoid infinite loop. */
18835 if (pending_templates && retries >= max_tinst_depth)
18837 tree decl = pending_templates->tinst->decl;
18839 error ("template instantiation depth exceeds maximum of %d"
18840 " instantiating %q+D, possibly from virtual table generation"
18841 " (use -ftemplate-depth= to increase the maximum)",
18842 max_tinst_depth, decl);
18843 if (TREE_CODE (decl) == FUNCTION_DECL)
18844 /* Pretend that we defined it. */
18845 DECL_INITIAL (decl) = error_mark_node;
18851 struct pending_template **t = &pending_templates;
18852 struct pending_template *last = NULL;
18856 tree instantiation = reopen_tinst_level ((*t)->tinst);
18857 bool complete = false;
18859 if (TYPE_P (instantiation))
18863 if (!COMPLETE_TYPE_P (instantiation))
18865 instantiate_class_template (instantiation);
18866 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
18867 for (fn = TYPE_METHODS (instantiation);
18869 fn = TREE_CHAIN (fn))
18870 if (! DECL_ARTIFICIAL (fn))
18871 instantiate_decl (fn,
18873 /*expl_inst_class_mem_p=*/false);
18874 if (COMPLETE_TYPE_P (instantiation))
18878 complete = COMPLETE_TYPE_P (instantiation);
18882 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
18883 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
18886 = instantiate_decl (instantiation,
18888 /*expl_inst_class_mem_p=*/false);
18889 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
18893 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
18894 || DECL_TEMPLATE_INSTANTIATED (instantiation));
18898 /* If INSTANTIATION has been instantiated, then we don't
18899 need to consider it again in the future. */
18907 current_tinst_level = NULL;
18909 last_pending_template = last;
18911 while (reconsider);
18913 input_location = saved_loc;
18916 /* Substitute ARGVEC into T, which is a list of initializers for
18917 either base class or a non-static data member. The TREE_PURPOSEs
18918 are DECLs, and the TREE_VALUEs are the initializer values. Used by
18919 instantiate_decl. */
18922 tsubst_initializer_list (tree t, tree argvec)
18924 tree inits = NULL_TREE;
18926 for (; t; t = TREE_CHAIN (t))
18930 tree expanded_bases = NULL_TREE;
18931 tree expanded_arguments = NULL_TREE;
18934 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
18939 /* Expand the base class expansion type into separate base
18941 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
18942 tf_warning_or_error,
18944 if (expanded_bases == error_mark_node)
18947 /* We'll be building separate TREE_LISTs of arguments for
18949 len = TREE_VEC_LENGTH (expanded_bases);
18950 expanded_arguments = make_tree_vec (len);
18951 for (i = 0; i < len; i++)
18952 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
18954 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
18955 expand each argument in the TREE_VALUE of t. */
18956 expr = make_node (EXPR_PACK_EXPANSION);
18957 PACK_EXPANSION_LOCAL_P (expr) = true;
18958 PACK_EXPANSION_PARAMETER_PACKS (expr) =
18959 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
18961 if (TREE_VALUE (t) == void_type_node)
18962 /* VOID_TYPE_NODE is used to indicate
18963 value-initialization. */
18965 for (i = 0; i < len; i++)
18966 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
18970 /* Substitute parameter packs into each argument in the
18972 in_base_initializer = 1;
18973 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
18975 tree expanded_exprs;
18977 /* Expand the argument. */
18978 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
18980 = tsubst_pack_expansion (expr, argvec,
18981 tf_warning_or_error,
18983 if (expanded_exprs == error_mark_node)
18986 /* Prepend each of the expanded expressions to the
18987 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
18988 for (i = 0; i < len; i++)
18990 TREE_VEC_ELT (expanded_arguments, i) =
18991 tree_cons (NULL_TREE,
18992 TREE_VEC_ELT (expanded_exprs, i),
18993 TREE_VEC_ELT (expanded_arguments, i));
18996 in_base_initializer = 0;
18998 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
18999 since we built them backwards. */
19000 for (i = 0; i < len; i++)
19002 TREE_VEC_ELT (expanded_arguments, i) =
19003 nreverse (TREE_VEC_ELT (expanded_arguments, i));
19008 for (i = 0; i < len; ++i)
19010 if (expanded_bases)
19012 decl = TREE_VEC_ELT (expanded_bases, i);
19013 decl = expand_member_init (decl);
19014 init = TREE_VEC_ELT (expanded_arguments, i);
19019 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
19020 tf_warning_or_error, NULL_TREE);
19022 decl = expand_member_init (decl);
19023 if (decl && !DECL_P (decl))
19024 in_base_initializer = 1;
19026 init = TREE_VALUE (t);
19028 if (init != void_type_node)
19029 init = tsubst_expr (init, argvec,
19030 tf_warning_or_error, NULL_TREE,
19031 /*integral_constant_expression_p=*/false);
19032 if (init == NULL_TREE && tmp != NULL_TREE)
19033 /* If we had an initializer but it instantiated to nothing,
19034 value-initialize the object. This will only occur when
19035 the initializer was a pack expansion where the parameter
19036 packs used in that expansion were of length zero. */
19037 init = void_type_node;
19038 in_base_initializer = 0;
19043 init = build_tree_list (decl, init);
19044 TREE_CHAIN (init) = inits;
19052 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
19055 set_current_access_from_decl (tree decl)
19057 if (TREE_PRIVATE (decl))
19058 current_access_specifier = access_private_node;
19059 else if (TREE_PROTECTED (decl))
19060 current_access_specifier = access_protected_node;
19062 current_access_specifier = access_public_node;
19065 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
19066 is the instantiation (which should have been created with
19067 start_enum) and ARGS are the template arguments to use. */
19070 tsubst_enum (tree tag, tree newtag, tree args)
19074 if (SCOPED_ENUM_P (newtag))
19075 begin_scope (sk_scoped_enum, newtag);
19077 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
19082 decl = TREE_VALUE (e);
19083 /* Note that in a template enum, the TREE_VALUE is the
19084 CONST_DECL, not the corresponding INTEGER_CST. */
19085 value = tsubst_expr (DECL_INITIAL (decl),
19086 args, tf_warning_or_error, NULL_TREE,
19087 /*integral_constant_expression_p=*/true);
19089 /* Give this enumeration constant the correct access. */
19090 set_current_access_from_decl (decl);
19092 /* Actually build the enumerator itself. */
19094 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
19097 if (SCOPED_ENUM_P (newtag))
19100 finish_enum_value_list (newtag);
19101 finish_enum (newtag);
19103 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
19104 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
19107 /* DECL is a FUNCTION_DECL that is a template specialization. Return
19108 its type -- but without substituting the innermost set of template
19109 arguments. So, innermost set of template parameters will appear in
19113 get_mostly_instantiated_function_type (tree decl)
19121 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
19122 targs = DECL_TI_ARGS (decl);
19123 tparms = DECL_TEMPLATE_PARMS (tmpl);
19124 parm_depth = TMPL_PARMS_DEPTH (tparms);
19126 /* There should be as many levels of arguments as there are levels
19128 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
19130 fn_type = TREE_TYPE (tmpl);
19132 if (parm_depth == 1)
19133 /* No substitution is necessary. */
19140 /* Replace the innermost level of the TARGS with NULL_TREEs to
19141 let tsubst know not to substitute for those parameters. */
19142 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
19143 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
19144 SET_TMPL_ARGS_LEVEL (partial_args, i,
19145 TMPL_ARGS_LEVEL (targs, i));
19146 SET_TMPL_ARGS_LEVEL (partial_args,
19147 TMPL_ARGS_DEPTH (targs),
19148 make_tree_vec (DECL_NTPARMS (tmpl)));
19150 /* Make sure that we can see identifiers, and compute access
19152 push_access_scope (decl);
19154 ++processing_template_decl;
19155 /* Now, do the (partial) substitution to figure out the
19156 appropriate function type. */
19157 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
19158 --processing_template_decl;
19160 /* Substitute into the template parameters to obtain the real
19161 innermost set of parameters. This step is important if the
19162 innermost set of template parameters contains value
19163 parameters whose types depend on outer template parameters. */
19164 TREE_VEC_LENGTH (partial_args)--;
19165 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
19167 pop_access_scope (decl);
19173 /* Return truthvalue if we're processing a template different from
19174 the last one involved in diagnostics. */
19176 problematic_instantiation_changed (void)
19178 return current_tinst_level != last_error_tinst_level;
19181 /* Remember current template involved in diagnostics. */
19183 record_last_problematic_instantiation (void)
19185 last_error_tinst_level = current_tinst_level;
19188 struct tinst_level *
19189 current_instantiation (void)
19191 return current_tinst_level;
19194 /* [temp.param] Check that template non-type parm TYPE is of an allowable
19195 type. Return zero for ok, nonzero for disallowed. Issue error and
19196 warning messages under control of COMPLAIN. */
19199 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
19201 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
19203 else if (POINTER_TYPE_P (type))
19205 else if (TYPE_PTR_TO_MEMBER_P (type))
19207 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
19209 else if (TREE_CODE (type) == TYPENAME_TYPE)
19211 else if (TREE_CODE (type) == DECLTYPE_TYPE)
19213 else if (TREE_CODE (type) == NULLPTR_TYPE)
19216 if (complain & tf_error)
19218 if (type == error_mark_node)
19219 inform (input_location, "invalid template non-type parameter");
19221 error ("%q#T is not a valid type for a template non-type parameter",
19227 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
19228 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
19231 dependent_type_p_r (tree type)
19237 A type is dependent if it is:
19239 -- a template parameter. Template template parameters are types
19240 for us (since TYPE_P holds true for them) so we handle
19242 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19243 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
19245 /* -- a qualified-id with a nested-name-specifier which contains a
19246 class-name that names a dependent type or whose unqualified-id
19247 names a dependent type. */
19248 if (TREE_CODE (type) == TYPENAME_TYPE)
19250 /* -- a cv-qualified type where the cv-unqualified type is
19252 type = TYPE_MAIN_VARIANT (type);
19253 /* -- a compound type constructed from any dependent type. */
19254 if (TYPE_PTR_TO_MEMBER_P (type))
19255 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
19256 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
19258 else if (TREE_CODE (type) == POINTER_TYPE
19259 || TREE_CODE (type) == REFERENCE_TYPE)
19260 return dependent_type_p (TREE_TYPE (type));
19261 else if (TREE_CODE (type) == FUNCTION_TYPE
19262 || TREE_CODE (type) == METHOD_TYPE)
19266 if (dependent_type_p (TREE_TYPE (type)))
19268 for (arg_type = TYPE_ARG_TYPES (type);
19270 arg_type = TREE_CHAIN (arg_type))
19271 if (dependent_type_p (TREE_VALUE (arg_type)))
19275 /* -- an array type constructed from any dependent type or whose
19276 size is specified by a constant expression that is
19279 We checked for type- and value-dependence of the bounds in
19280 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
19281 if (TREE_CODE (type) == ARRAY_TYPE)
19283 if (TYPE_DOMAIN (type)
19284 && dependent_type_p (TYPE_DOMAIN (type)))
19286 return dependent_type_p (TREE_TYPE (type));
19289 /* -- a template-id in which either the template name is a template
19291 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
19293 /* ... or any of the template arguments is a dependent type or
19294 an expression that is type-dependent or value-dependent. */
19295 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
19296 && (any_dependent_template_arguments_p
19297 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
19300 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
19301 dependent; if the argument of the `typeof' expression is not
19302 type-dependent, then it should already been have resolved. */
19303 if (TREE_CODE (type) == TYPEOF_TYPE
19304 || TREE_CODE (type) == DECLTYPE_TYPE
19305 || TREE_CODE (type) == UNDERLYING_TYPE)
19308 /* A template argument pack is dependent if any of its packed
19310 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
19312 tree args = ARGUMENT_PACK_ARGS (type);
19313 int i, len = TREE_VEC_LENGTH (args);
19314 for (i = 0; i < len; ++i)
19315 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19319 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
19320 be template parameters. */
19321 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
19324 /* The standard does not specifically mention types that are local
19325 to template functions or local classes, but they should be
19326 considered dependent too. For example:
19328 template <int I> void f() {
19333 The size of `E' cannot be known until the value of `I' has been
19334 determined. Therefore, `E' must be considered dependent. */
19335 scope = TYPE_CONTEXT (type);
19336 if (scope && TYPE_P (scope))
19337 return dependent_type_p (scope);
19338 /* Don't use type_dependent_expression_p here, as it can lead
19339 to infinite recursion trying to determine whether a lambda
19340 nested in a lambda is dependent (c++/47687). */
19341 else if (scope && TREE_CODE (scope) == FUNCTION_DECL
19342 && DECL_LANG_SPECIFIC (scope)
19343 && DECL_TEMPLATE_INFO (scope)
19344 && (any_dependent_template_arguments_p
19345 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
19348 /* Other types are non-dependent. */
19352 /* Returns TRUE if TYPE is dependent, in the sense of
19353 [temp.dep.type]. Note that a NULL type is considered dependent. */
19356 dependent_type_p (tree type)
19358 /* If there are no template parameters in scope, then there can't be
19359 any dependent types. */
19360 if (!processing_template_decl)
19362 /* If we are not processing a template, then nobody should be
19363 providing us with a dependent type. */
19365 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
19369 /* If the type is NULL, we have not computed a type for the entity
19370 in question; in that case, the type is dependent. */
19374 /* Erroneous types can be considered non-dependent. */
19375 if (type == error_mark_node)
19378 /* If we have not already computed the appropriate value for TYPE,
19380 if (!TYPE_DEPENDENT_P_VALID (type))
19382 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
19383 TYPE_DEPENDENT_P_VALID (type) = 1;
19386 return TYPE_DEPENDENT_P (type);
19389 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
19390 lookup. In other words, a dependent type that is not the current
19394 dependent_scope_p (tree scope)
19396 return (scope && TYPE_P (scope) && dependent_type_p (scope)
19397 && !currently_open_class (scope));
19400 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
19401 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
19404 /* Note that this predicate is not appropriate for general expressions;
19405 only constant expressions (that satisfy potential_constant_expression)
19406 can be tested for value dependence.
19408 We should really also have a predicate for "instantiation-dependent".
19410 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent.
19411 (what about instantiation-dependent constant-expressions?)
19412 is_late_template_attribute: defer if instantiation-dependent.
19413 compute_array_index_type: proceed if constant and not t- or v-dependent
19414 if instantiation-dependent, need to remember full expression
19415 uses_template_parms: FIXME - need to audit callers
19416 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p?
19417 dependent_type_p [array_type]: dependent if index type is dependent
19419 static_assert - instantiation-dependent */
19422 value_dependent_expression_p (tree expression)
19424 if (!processing_template_decl)
19427 /* A name declared with a dependent type. */
19428 if (DECL_P (expression) && type_dependent_expression_p (expression))
19431 switch (TREE_CODE (expression))
19433 case IDENTIFIER_NODE:
19434 /* A name that has not been looked up -- must be dependent. */
19437 case TEMPLATE_PARM_INDEX:
19438 /* A non-type template parm. */
19442 /* A non-type template parm. */
19443 if (DECL_TEMPLATE_PARM_P (expression))
19445 return value_dependent_expression_p (DECL_INITIAL (expression));
19448 /* A constant with literal type and is initialized
19449 with an expression that is value-dependent. */
19450 if (DECL_INITIAL (expression)
19451 && decl_constant_var_p (expression)
19452 && value_dependent_expression_p (DECL_INITIAL (expression)))
19456 case DYNAMIC_CAST_EXPR:
19457 case STATIC_CAST_EXPR:
19458 case CONST_CAST_EXPR:
19459 case REINTERPRET_CAST_EXPR:
19461 /* These expressions are value-dependent if the type to which
19462 the cast occurs is dependent or the expression being casted
19463 is value-dependent. */
19465 tree type = TREE_TYPE (expression);
19467 if (dependent_type_p (type))
19470 /* A functional cast has a list of operands. */
19471 expression = TREE_OPERAND (expression, 0);
19474 /* If there are no operands, it must be an expression such
19475 as "int()". This should not happen for aggregate types
19476 because it would form non-constant expressions. */
19477 gcc_assert (cxx_dialect >= cxx0x
19478 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
19483 if (TREE_CODE (expression) == TREE_LIST)
19484 return any_value_dependent_elements_p (expression);
19486 return value_dependent_expression_p (expression);
19492 /* A `sizeof' expression is value-dependent if the operand is
19493 type-dependent or is a pack expansion. */
19494 expression = TREE_OPERAND (expression, 0);
19495 if (PACK_EXPANSION_P (expression))
19497 else if (TYPE_P (expression))
19498 return dependent_type_p (expression);
19499 return type_dependent_expression_p (expression);
19501 case AT_ENCODE_EXPR:
19502 /* An 'encode' expression is value-dependent if the operand is
19504 expression = TREE_OPERAND (expression, 0);
19505 return dependent_type_p (expression);
19507 case NOEXCEPT_EXPR:
19508 expression = TREE_OPERAND (expression, 0);
19509 return type_dependent_expression_p (expression);
19513 tree name = TREE_OPERAND (expression, 1);
19514 return value_dependent_expression_p (name);
19517 case COMPONENT_REF:
19518 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
19519 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
19521 case NONTYPE_ARGUMENT_PACK:
19522 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
19523 is value-dependent. */
19525 tree values = ARGUMENT_PACK_ARGS (expression);
19526 int i, len = TREE_VEC_LENGTH (values);
19528 for (i = 0; i < len; ++i)
19529 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
19537 tree type2 = TRAIT_EXPR_TYPE2 (expression);
19538 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
19539 || (type2 ? dependent_type_p (type2) : false));
19543 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19544 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
19547 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19548 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
19552 tree op = TREE_OPERAND (expression, 0);
19553 return (value_dependent_expression_p (op)
19554 || has_value_dependent_address (op));
19559 tree fn = get_callee_fndecl (expression);
19561 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
19563 nargs = call_expr_nargs (expression);
19564 for (i = 0; i < nargs; ++i)
19566 tree op = CALL_EXPR_ARG (expression, i);
19567 /* In a call to a constexpr member function, look through the
19568 implicit ADDR_EXPR on the object argument so that it doesn't
19569 cause the call to be considered value-dependent. We also
19570 look through it in potential_constant_expression. */
19571 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
19572 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
19573 && TREE_CODE (op) == ADDR_EXPR)
19574 op = TREE_OPERAND (op, 0);
19575 if (value_dependent_expression_p (op))
19581 case TEMPLATE_ID_EXPR:
19582 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
19584 return type_dependent_expression_p (expression);
19590 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
19591 if (value_dependent_expression_p (val))
19597 /* Treat a GNU statement expression as dependent to avoid crashing
19598 under fold_non_dependent_expr; it can't be constant. */
19602 /* A constant expression is value-dependent if any subexpression is
19603 value-dependent. */
19604 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
19606 case tcc_reference:
19608 case tcc_comparison:
19610 case tcc_expression:
19613 int i, len = cp_tree_operand_length (expression);
19615 for (i = 0; i < len; i++)
19617 tree t = TREE_OPERAND (expression, i);
19619 /* In some cases, some of the operands may be missing.l
19620 (For example, in the case of PREDECREMENT_EXPR, the
19621 amount to increment by may be missing.) That doesn't
19622 make the expression dependent. */
19623 if (t && value_dependent_expression_p (t))
19634 /* The expression is not value-dependent. */
19638 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
19639 [temp.dep.expr]. Note that an expression with no type is
19640 considered dependent. Other parts of the compiler arrange for an
19641 expression with type-dependent subexpressions to have no type, so
19642 this function doesn't have to be fully recursive. */
19645 type_dependent_expression_p (tree expression)
19647 if (!processing_template_decl)
19650 if (expression == error_mark_node)
19653 /* An unresolved name is always dependent. */
19654 if (TREE_CODE (expression) == IDENTIFIER_NODE
19655 || TREE_CODE (expression) == USING_DECL)
19658 /* Some expression forms are never type-dependent. */
19659 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
19660 || TREE_CODE (expression) == SIZEOF_EXPR
19661 || TREE_CODE (expression) == ALIGNOF_EXPR
19662 || TREE_CODE (expression) == AT_ENCODE_EXPR
19663 || TREE_CODE (expression) == NOEXCEPT_EXPR
19664 || TREE_CODE (expression) == TRAIT_EXPR
19665 || TREE_CODE (expression) == TYPEID_EXPR
19666 || TREE_CODE (expression) == DELETE_EXPR
19667 || TREE_CODE (expression) == VEC_DELETE_EXPR
19668 || TREE_CODE (expression) == THROW_EXPR)
19671 /* The types of these expressions depends only on the type to which
19672 the cast occurs. */
19673 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
19674 || TREE_CODE (expression) == STATIC_CAST_EXPR
19675 || TREE_CODE (expression) == CONST_CAST_EXPR
19676 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
19677 || TREE_CODE (expression) == IMPLICIT_CONV_EXPR
19678 || TREE_CODE (expression) == CAST_EXPR)
19679 return dependent_type_p (TREE_TYPE (expression));
19681 /* The types of these expressions depends only on the type created
19682 by the expression. */
19683 if (TREE_CODE (expression) == NEW_EXPR
19684 || TREE_CODE (expression) == VEC_NEW_EXPR)
19686 /* For NEW_EXPR tree nodes created inside a template, either
19687 the object type itself or a TREE_LIST may appear as the
19689 tree type = TREE_OPERAND (expression, 1);
19690 if (TREE_CODE (type) == TREE_LIST)
19691 /* This is an array type. We need to check array dimensions
19693 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
19694 || value_dependent_expression_p
19695 (TREE_OPERAND (TREE_VALUE (type), 1));
19697 return dependent_type_p (type);
19700 if (TREE_CODE (expression) == SCOPE_REF)
19702 tree scope = TREE_OPERAND (expression, 0);
19703 tree name = TREE_OPERAND (expression, 1);
19705 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
19706 contains an identifier associated by name lookup with one or more
19707 declarations declared with a dependent type, or...a
19708 nested-name-specifier or qualified-id that names a member of an
19709 unknown specialization. */
19710 return (type_dependent_expression_p (name)
19711 || dependent_scope_p (scope));
19714 if (TREE_CODE (expression) == FUNCTION_DECL
19715 && DECL_LANG_SPECIFIC (expression)
19716 && DECL_TEMPLATE_INFO (expression)
19717 && (any_dependent_template_arguments_p
19718 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
19721 if (TREE_CODE (expression) == TEMPLATE_DECL
19722 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
19725 if (TREE_CODE (expression) == STMT_EXPR)
19726 expression = stmt_expr_value_expr (expression);
19728 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
19733 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
19735 if (type_dependent_expression_p (elt))
19741 /* A static data member of the current instantiation with incomplete
19742 array type is type-dependent, as the definition and specializations
19743 can have different bounds. */
19744 if (TREE_CODE (expression) == VAR_DECL
19745 && DECL_CLASS_SCOPE_P (expression)
19746 && dependent_type_p (DECL_CONTEXT (expression))
19747 && VAR_HAD_UNKNOWN_BOUND (expression))
19750 if (TREE_TYPE (expression) == unknown_type_node)
19752 if (TREE_CODE (expression) == ADDR_EXPR)
19753 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
19754 if (TREE_CODE (expression) == COMPONENT_REF
19755 || TREE_CODE (expression) == OFFSET_REF)
19757 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
19759 expression = TREE_OPERAND (expression, 1);
19760 if (TREE_CODE (expression) == IDENTIFIER_NODE)
19763 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
19764 if (TREE_CODE (expression) == SCOPE_REF)
19767 if (BASELINK_P (expression))
19768 expression = BASELINK_FUNCTIONS (expression);
19770 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
19772 if (any_dependent_template_arguments_p
19773 (TREE_OPERAND (expression, 1)))
19775 expression = TREE_OPERAND (expression, 0);
19777 gcc_assert (TREE_CODE (expression) == OVERLOAD
19778 || TREE_CODE (expression) == FUNCTION_DECL);
19782 if (type_dependent_expression_p (OVL_CURRENT (expression)))
19784 expression = OVL_NEXT (expression);
19789 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
19791 return (dependent_type_p (TREE_TYPE (expression)));
19794 /* Like type_dependent_expression_p, but it also works while not processing
19795 a template definition, i.e. during substitution or mangling. */
19798 type_dependent_expression_p_push (tree expr)
19801 ++processing_template_decl;
19802 b = type_dependent_expression_p (expr);
19803 --processing_template_decl;
19807 /* Returns TRUE if ARGS contains a type-dependent expression. */
19810 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
19815 FOR_EACH_VEC_ELT (tree, args, i, arg)
19817 if (type_dependent_expression_p (arg))
19823 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19824 expressions) contains any type-dependent expressions. */
19827 any_type_dependent_elements_p (const_tree list)
19829 for (; list; list = TREE_CHAIN (list))
19830 if (value_dependent_expression_p (TREE_VALUE (list)))
19836 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
19837 expressions) contains any value-dependent expressions. */
19840 any_value_dependent_elements_p (const_tree list)
19842 for (; list; list = TREE_CHAIN (list))
19843 if (value_dependent_expression_p (TREE_VALUE (list)))
19849 /* Returns TRUE if the ARG (a template argument) is dependent. */
19852 dependent_template_arg_p (tree arg)
19854 if (!processing_template_decl)
19857 /* Assume a template argument that was wrongly written by the user
19858 is dependent. This is consistent with what
19859 any_dependent_template_arguments_p [that calls this function]
19861 if (!arg || arg == error_mark_node)
19864 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
19865 arg = ARGUMENT_PACK_SELECT_ARG (arg);
19867 if (TREE_CODE (arg) == TEMPLATE_DECL
19868 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19869 return dependent_template_p (arg);
19870 else if (ARGUMENT_PACK_P (arg))
19872 tree args = ARGUMENT_PACK_ARGS (arg);
19873 int i, len = TREE_VEC_LENGTH (args);
19874 for (i = 0; i < len; ++i)
19876 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19882 else if (TYPE_P (arg))
19883 return dependent_type_p (arg);
19885 return (type_dependent_expression_p (arg)
19886 || value_dependent_expression_p (arg));
19889 /* Returns true if ARGS (a collection of template arguments) contains
19890 any types that require structural equality testing. */
19893 any_template_arguments_need_structural_equality_p (tree args)
19900 if (args == error_mark_node)
19903 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19905 tree level = TMPL_ARGS_LEVEL (args, i + 1);
19906 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19908 tree arg = TREE_VEC_ELT (level, j);
19909 tree packed_args = NULL_TREE;
19912 if (ARGUMENT_PACK_P (arg))
19914 /* Look inside the argument pack. */
19915 packed_args = ARGUMENT_PACK_ARGS (arg);
19916 len = TREE_VEC_LENGTH (packed_args);
19919 for (k = 0; k < len; ++k)
19922 arg = TREE_VEC_ELT (packed_args, k);
19924 if (error_operand_p (arg))
19926 else if (TREE_CODE (arg) == TEMPLATE_DECL
19927 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
19929 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
19931 else if (!TYPE_P (arg) && TREE_TYPE (arg)
19932 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
19941 /* Returns true if ARGS (a collection of template arguments) contains
19942 any dependent arguments. */
19945 any_dependent_template_arguments_p (const_tree args)
19952 if (args == error_mark_node)
19955 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
19957 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
19958 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
19959 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
19966 /* Returns TRUE if the template TMPL is dependent. */
19969 dependent_template_p (tree tmpl)
19971 if (TREE_CODE (tmpl) == OVERLOAD)
19975 if (dependent_template_p (OVL_CURRENT (tmpl)))
19977 tmpl = OVL_NEXT (tmpl);
19982 /* Template template parameters are dependent. */
19983 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
19984 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
19986 /* So are names that have not been looked up. */
19987 if (TREE_CODE (tmpl) == SCOPE_REF
19988 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
19990 /* So are member templates of dependent classes. */
19991 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
19992 return dependent_type_p (DECL_CONTEXT (tmpl));
19996 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
19999 dependent_template_id_p (tree tmpl, tree args)
20001 return (dependent_template_p (tmpl)
20002 || any_dependent_template_arguments_p (args));
20005 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
20009 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
20013 if (!processing_template_decl)
20016 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
20018 tree decl = TREE_VEC_ELT (declv, i);
20019 tree init = TREE_VEC_ELT (initv, i);
20020 tree cond = TREE_VEC_ELT (condv, i);
20021 tree incr = TREE_VEC_ELT (incrv, i);
20023 if (type_dependent_expression_p (decl))
20026 if (init && type_dependent_expression_p (init))
20029 if (type_dependent_expression_p (cond))
20032 if (COMPARISON_CLASS_P (cond)
20033 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
20034 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
20037 if (TREE_CODE (incr) == MODOP_EXPR)
20039 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
20040 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
20043 else if (type_dependent_expression_p (incr))
20045 else if (TREE_CODE (incr) == MODIFY_EXPR)
20047 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
20049 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
20051 tree t = TREE_OPERAND (incr, 1);
20052 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
20053 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
20062 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
20063 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
20064 no such TYPE can be found. Note that this function peers inside
20065 uninstantiated templates and therefore should be used only in
20066 extremely limited situations. ONLY_CURRENT_P restricts this
20067 peering to the currently open classes hierarchy (which is required
20068 when comparing types). */
20071 resolve_typename_type (tree type, bool only_current_p)
20080 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
20082 scope = TYPE_CONTEXT (type);
20083 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
20084 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
20085 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
20086 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
20087 identifier of the TYPENAME_TYPE anymore.
20088 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
20089 TYPENAME_TYPE instead, we avoid messing up with a possible
20090 typedef variant case. */
20091 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
20093 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
20094 it first before we can figure out what NAME refers to. */
20095 if (TREE_CODE (scope) == TYPENAME_TYPE)
20096 scope = resolve_typename_type (scope, only_current_p);
20097 /* If we don't know what SCOPE refers to, then we cannot resolve the
20099 if (TREE_CODE (scope) == TYPENAME_TYPE)
20101 /* If the SCOPE is a template type parameter, we have no way of
20102 resolving the name. */
20103 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
20105 /* If the SCOPE is not the current instantiation, there's no reason
20106 to look inside it. */
20107 if (only_current_p && !currently_open_class (scope))
20109 /* If this is a typedef, we don't want to look inside (c++/11987). */
20110 if (typedef_variant_p (type))
20112 /* If SCOPE isn't the template itself, it will not have a valid
20113 TYPE_FIELDS list. */
20114 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
20115 /* scope is either the template itself or a compatible instantiation
20116 like X<T>, so look up the name in the original template. */
20117 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
20119 /* scope is a partial instantiation, so we can't do the lookup or we
20120 will lose the template arguments. */
20122 /* Enter the SCOPE so that name lookup will be resolved as if we
20123 were in the class definition. In particular, SCOPE will no
20124 longer be considered a dependent type. */
20125 pushed_scope = push_scope (scope);
20126 /* Look up the declaration. */
20127 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true,
20128 tf_warning_or_error);
20130 result = NULL_TREE;
20132 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
20133 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
20136 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
20137 && TREE_CODE (decl) == TYPE_DECL)
20139 result = TREE_TYPE (decl);
20140 if (result == error_mark_node)
20141 result = NULL_TREE;
20143 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
20144 && DECL_CLASS_TEMPLATE_P (decl))
20148 /* Obtain the template and the arguments. */
20149 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
20150 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
20151 /* Instantiate the template. */
20152 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
20153 /*entering_scope=*/0,
20154 tf_error | tf_user);
20155 if (result == error_mark_node)
20156 result = NULL_TREE;
20159 /* Leave the SCOPE. */
20161 pop_scope (pushed_scope);
20163 /* If we failed to resolve it, return the original typename. */
20167 /* If lookup found a typename type, resolve that too. */
20168 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
20170 /* Ill-formed programs can cause infinite recursion here, so we
20171 must catch that. */
20172 TYPENAME_IS_RESOLVING_P (type) = 1;
20173 result = resolve_typename_type (result, only_current_p);
20174 TYPENAME_IS_RESOLVING_P (type) = 0;
20177 /* Qualify the resulting type. */
20178 quals = cp_type_quals (type);
20180 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
20185 /* EXPR is an expression which is not type-dependent. Return a proxy
20186 for EXPR that can be used to compute the types of larger
20187 expressions containing EXPR. */
20190 build_non_dependent_expr (tree expr)
20194 #ifdef ENABLE_CHECKING
20195 /* Try to get a constant value for all non-type-dependent expressions in
20196 order to expose bugs in *_dependent_expression_p and constexpr. */
20197 if (cxx_dialect >= cxx0x)
20198 maybe_constant_value (fold_non_dependent_expr_sfinae (expr, tf_none));
20201 /* Preserve OVERLOADs; the functions must be available to resolve
20204 if (TREE_CODE (inner_expr) == STMT_EXPR)
20205 inner_expr = stmt_expr_value_expr (inner_expr);
20206 if (TREE_CODE (inner_expr) == ADDR_EXPR)
20207 inner_expr = TREE_OPERAND (inner_expr, 0);
20208 if (TREE_CODE (inner_expr) == COMPONENT_REF)
20209 inner_expr = TREE_OPERAND (inner_expr, 1);
20210 if (is_overloaded_fn (inner_expr)
20211 || TREE_CODE (inner_expr) == OFFSET_REF)
20213 /* There is no need to return a proxy for a variable. */
20214 if (TREE_CODE (expr) == VAR_DECL)
20216 /* Preserve string constants; conversions from string constants to
20217 "char *" are allowed, even though normally a "const char *"
20218 cannot be used to initialize a "char *". */
20219 if (TREE_CODE (expr) == STRING_CST)
20221 /* Preserve arithmetic constants, as an optimization -- there is no
20222 reason to create a new node. */
20223 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
20225 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
20226 There is at least one place where we want to know that a
20227 particular expression is a throw-expression: when checking a ?:
20228 expression, there are special rules if the second or third
20229 argument is a throw-expression. */
20230 if (TREE_CODE (expr) == THROW_EXPR)
20233 /* Don't wrap an initializer list, we need to be able to look inside. */
20234 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
20237 if (TREE_CODE (expr) == COND_EXPR)
20238 return build3 (COND_EXPR,
20240 TREE_OPERAND (expr, 0),
20241 (TREE_OPERAND (expr, 1)
20242 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
20243 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
20244 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
20245 if (TREE_CODE (expr) == COMPOUND_EXPR
20246 && !COMPOUND_EXPR_OVERLOADED (expr))
20247 return build2 (COMPOUND_EXPR,
20249 TREE_OPERAND (expr, 0),
20250 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
20252 /* If the type is unknown, it can't really be non-dependent */
20253 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
20255 /* Otherwise, build a NON_DEPENDENT_EXPR. */
20256 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
20259 /* ARGS is a vector of expressions as arguments to a function call.
20260 Replace the arguments with equivalent non-dependent expressions.
20261 This modifies ARGS in place. */
20264 make_args_non_dependent (VEC(tree,gc) *args)
20269 FOR_EACH_VEC_ELT (tree, args, ix, arg)
20271 tree newarg = build_non_dependent_expr (arg);
20273 VEC_replace (tree, args, ix, newarg);
20277 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
20278 with a level one deeper than the actual template parms. */
20283 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
20284 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
20285 TYPE_DECL, get_identifier ("auto"), au);
20286 TYPE_STUB_DECL (au) = TYPE_NAME (au);
20287 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
20288 (0, processing_template_decl + 1, processing_template_decl + 1,
20289 0, TYPE_NAME (au), NULL_TREE);
20290 TYPE_CANONICAL (au) = canonical_type_parameter (au);
20291 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
20292 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
20297 /* Given type ARG, return std::initializer_list<ARG>. */
20302 tree std_init_list = namespace_binding
20303 (get_identifier ("initializer_list"), std_node);
20305 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
20307 error ("deducing from brace-enclosed initializer list requires "
20308 "#include <initializer_list>");
20309 return error_mark_node;
20311 argvec = make_tree_vec (1);
20312 TREE_VEC_ELT (argvec, 0) = arg;
20313 return lookup_template_class (std_init_list, argvec, NULL_TREE,
20314 NULL_TREE, 0, tf_warning_or_error);
20317 /* Replace auto in TYPE with std::initializer_list<auto>. */
20320 listify_autos (tree type, tree auto_node)
20322 tree init_auto = listify (auto_node);
20323 tree argvec = make_tree_vec (1);
20324 TREE_VEC_ELT (argvec, 0) = init_auto;
20325 if (processing_template_decl)
20326 argvec = add_to_template_args (current_template_args (), argvec);
20327 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20330 /* walk_tree helper for do_auto_deduction. */
20333 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
20336 /* Is this a variable with the type we're looking for? */
20338 && TREE_TYPE (*tp) == type)
20344 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
20345 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
20348 do_auto_deduction (tree type, tree init, tree auto_node)
20350 tree parms, tparms, targs;
20355 if (processing_template_decl
20356 && (TREE_TYPE (init) == NULL_TREE
20357 || BRACE_ENCLOSED_INITIALIZER_P (init)))
20358 /* Not enough information to try this yet. */
20361 /* The name of the object being declared shall not appear in the
20362 initializer expression. */
20363 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type);
20366 error ("variable %q#D with %<auto%> type used in its own "
20367 "initializer", decl);
20368 return error_mark_node;
20371 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
20372 with either a new invented type template parameter U or, if the
20373 initializer is a braced-init-list (8.5.4), with
20374 std::initializer_list<U>. */
20375 if (BRACE_ENCLOSED_INITIALIZER_P (init))
20376 type = listify_autos (type, auto_node);
20378 init = resolve_nondeduced_context (init);
20380 parms = build_tree_list (NULL_TREE, type);
20382 tparms = make_tree_vec (1);
20383 targs = make_tree_vec (1);
20384 TREE_VEC_ELT (tparms, 0)
20385 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
20386 val = type_unification_real (tparms, targs, parms, args, 1, 0,
20387 DEDUCE_CALL, LOOKUP_NORMAL,
20388 /*explain_p=*/false);
20391 if (processing_template_decl)
20392 /* Try again at instantiation time. */
20394 if (type && type != error_mark_node)
20395 /* If type is error_mark_node a diagnostic must have been
20396 emitted by now. Also, having a mention to '<type error>'
20397 in the diagnostic is not really useful to the user. */
20398 error ("unable to deduce %qT from %qE", type, init);
20399 return error_mark_node;
20402 /* If the list of declarators contains more than one declarator, the type
20403 of each declared variable is determined as described above. If the
20404 type deduced for the template parameter U is not the same in each
20405 deduction, the program is ill-formed. */
20406 if (TREE_TYPE (auto_node)
20407 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
20409 error ("inconsistent deduction for %qT: %qT and then %qT",
20410 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
20411 return error_mark_node;
20413 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
20415 if (processing_template_decl)
20416 targs = add_to_template_args (current_template_args (), targs);
20417 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
20420 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
20424 splice_late_return_type (tree type, tree late_return_type)
20428 if (late_return_type == NULL_TREE)
20430 argvec = make_tree_vec (1);
20431 TREE_VEC_ELT (argvec, 0) = late_return_type;
20432 if (processing_template_parmlist)
20433 /* For a late-specified return type in a template type-parameter, we
20434 need to add a dummy argument level for its parmlist. */
20435 argvec = add_to_template_args
20436 (make_tree_vec (processing_template_parmlist), argvec);
20437 if (current_template_parms)
20438 argvec = add_to_template_args (current_template_args (), argvec);
20439 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20442 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
20445 is_auto (const_tree type)
20447 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
20448 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
20454 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
20455 appear as a type-specifier for the declaration in question, we don't
20456 have to look through the whole type. */
20459 type_uses_auto (tree type)
20461 enum tree_code code;
20462 if (is_auto (type))
20465 code = TREE_CODE (type);
20467 if (code == POINTER_TYPE || code == REFERENCE_TYPE
20468 || code == OFFSET_TYPE || code == FUNCTION_TYPE
20469 || code == METHOD_TYPE || code == ARRAY_TYPE)
20470 return type_uses_auto (TREE_TYPE (type));
20472 if (TYPE_PTRMEMFUNC_P (type))
20473 return type_uses_auto (TREE_TYPE (TREE_TYPE
20474 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
20479 /* For a given template T, return the vector of typedefs referenced
20480 in T for which access check is needed at T instantiation time.
20481 T is either a FUNCTION_DECL or a RECORD_TYPE.
20482 Those typedefs were added to T by the function
20483 append_type_to_template_for_access_check. */
20485 VEC(qualified_typedef_usage_t,gc)*
20486 get_types_needing_access_check (tree t)
20489 VEC(qualified_typedef_usage_t,gc) *result = NULL;
20491 if (!t || t == error_mark_node)
20494 if (!(ti = get_template_info (t)))
20497 if (CLASS_TYPE_P (t)
20498 || TREE_CODE (t) == FUNCTION_DECL)
20500 if (!TI_TEMPLATE (ti))
20503 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
20509 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
20510 tied to T. That list of typedefs will be access checked at
20511 T instantiation time.
20512 T is either a FUNCTION_DECL or a RECORD_TYPE.
20513 TYPE_DECL is a TYPE_DECL node representing a typedef.
20514 SCOPE is the scope through which TYPE_DECL is accessed.
20515 LOCATION is the location of the usage point of TYPE_DECL.
20517 This function is a subroutine of
20518 append_type_to_template_for_access_check. */
20521 append_type_to_template_for_access_check_1 (tree t,
20524 location_t location)
20526 qualified_typedef_usage_t typedef_usage;
20529 if (!t || t == error_mark_node)
20532 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
20533 || CLASS_TYPE_P (t))
20535 && TREE_CODE (type_decl) == TYPE_DECL
20538 if (!(ti = get_template_info (t)))
20541 gcc_assert (TI_TEMPLATE (ti));
20543 typedef_usage.typedef_decl = type_decl;
20544 typedef_usage.context = scope;
20545 typedef_usage.locus = location;
20547 VEC_safe_push (qualified_typedef_usage_t, gc,
20548 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti),
20552 /* Append TYPE_DECL to the template TEMPL.
20553 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
20554 At TEMPL instanciation time, TYPE_DECL will be checked to see
20555 if it can be accessed through SCOPE.
20556 LOCATION is the location of the usage point of TYPE_DECL.
20558 e.g. consider the following code snippet:
20565 template<class U> struct S
20567 C::myint mi; // <-- usage point of the typedef C::myint
20572 At S<char> instantiation time, we need to check the access of C::myint
20573 In other words, we need to check the access of the myint typedef through
20574 the C scope. For that purpose, this function will add the myint typedef
20575 and the scope C through which its being accessed to a list of typedefs
20576 tied to the template S. That list will be walked at template instantiation
20577 time and access check performed on each typedefs it contains.
20578 Note that this particular code snippet should yield an error because
20579 myint is private to C. */
20582 append_type_to_template_for_access_check (tree templ,
20585 location_t location)
20587 qualified_typedef_usage_t *iter;
20590 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
20592 /* Make sure we don't append the type to the template twice. */
20593 FOR_EACH_VEC_ELT (qualified_typedef_usage_t,
20594 get_types_needing_access_check (templ),
20596 if (iter->typedef_decl == type_decl && scope == iter->context)
20599 append_type_to_template_for_access_check_1 (templ, type_decl,
20603 /* Set up the hash tables for template instantiations. */
20606 init_template_processing (void)
20608 decl_specializations = htab_create_ggc (37,
20609 hash_specialization,
20610 eq_specializations,
20612 type_specializations = htab_create_ggc (37,
20613 hash_specialization,
20614 eq_specializations,
20618 /* Print stats about the template hash tables for -fstats. */
20621 print_template_statistics (void)
20623 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
20624 "%f collisions\n", (long) htab_size (decl_specializations),
20625 (long) htab_elements (decl_specializations),
20626 htab_collisions (decl_specializations));
20627 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
20628 "%f collisions\n", (long) htab_size (type_specializations),
20629 (long) htab_elements (type_specializations),
20630 htab_collisions (type_specializations));
20633 #include "gt-cp-pt.h"