1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009
4 Free Software Foundation, Inc.
5 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
6 Rewritten by Jason Merrill (jason@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
39 #include "cp-objcp-common.h"
40 #include "tree-inline.h"
47 #include "tree-iterator.h"
50 /* The type of functions taking a tree, and some additional data, and
52 typedef int (*tree_fn_t) (tree, void*);
54 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
55 instantiations have been deferred, either because their definitions
56 were not yet available, or because we were putting off doing the work. */
57 struct GTY (()) pending_template {
58 struct pending_template *next;
59 struct tinst_level *tinst;
62 static GTY(()) struct pending_template *pending_templates;
63 static GTY(()) struct pending_template *last_pending_template;
65 int processing_template_parmlist;
66 static int template_header_count;
68 static GTY(()) tree saved_trees;
69 static VEC(int,heap) *inline_parm_levels;
71 static GTY(()) struct tinst_level *current_tinst_level;
73 static GTY(()) tree saved_access_scope;
75 /* Live only within one (recursive) call to tsubst_expr. We use
76 this to pass the statement expression node from the STMT_EXPR
77 to the EXPR_STMT that is its result. */
78 static tree cur_stmt_expr;
80 /* A map from local variable declarations in the body of the template
81 presently being instantiated to the corresponding instantiated
83 static htab_t local_specializations;
85 typedef struct GTY(()) spec_entry
92 static GTY ((param_is (spec_entry)))
93 htab_t decl_specializations;
95 static GTY ((param_is (spec_entry)))
96 htab_t type_specializations;
98 /* Contains canonical template parameter types. The vector is indexed by
99 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
100 TREE_LIST, whose TREE_VALUEs contain the canonical template
101 parameters of various types and levels. */
102 static GTY(()) VEC(tree,gc) *canonical_template_parms;
104 #define UNIFY_ALLOW_NONE 0
105 #define UNIFY_ALLOW_MORE_CV_QUAL 1
106 #define UNIFY_ALLOW_LESS_CV_QUAL 2
107 #define UNIFY_ALLOW_DERIVED 4
108 #define UNIFY_ALLOW_INTEGER 8
109 #define UNIFY_ALLOW_OUTER_LEVEL 16
110 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
111 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
113 static void push_access_scope (tree);
114 static void pop_access_scope (tree);
115 static bool resolve_overloaded_unification (tree, tree, tree, tree,
116 unification_kind_t, int);
117 static int try_one_overload (tree, tree, tree, tree, tree,
118 unification_kind_t, int, bool);
119 static int unify (tree, tree, tree, tree, int);
120 static void add_pending_template (tree);
121 static int push_tinst_level (tree);
122 static void pop_tinst_level (void);
123 static tree reopen_tinst_level (struct tinst_level *);
124 static tree tsubst_initializer_list (tree, tree);
125 static tree get_class_bindings (tree, tree, tree);
126 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
128 static void tsubst_enum (tree, tree, tree);
129 static tree add_to_template_args (tree, tree);
130 static tree add_outermost_template_args (tree, tree);
131 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
132 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
134 static int type_unification_real (tree, tree, tree, const tree *,
135 unsigned int, int, unification_kind_t, int);
136 static void note_template_header (int);
137 static tree convert_nontype_argument_function (tree, tree);
138 static tree convert_nontype_argument (tree, tree);
139 static tree convert_template_argument (tree, tree, tree,
140 tsubst_flags_t, int, tree);
141 static int for_each_template_parm (tree, tree_fn_t, void*,
142 struct pointer_set_t*, bool);
143 static tree expand_template_argument_pack (tree);
144 static tree build_template_parm_index (int, int, int, tree, tree);
145 static bool inline_needs_template_parms (tree);
146 static void push_inline_template_parms_recursive (tree, int);
147 static tree retrieve_local_specialization (tree);
148 static void register_local_specialization (tree, tree);
149 static hashval_t hash_specialization (const void *p);
150 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
151 static int mark_template_parm (tree, void *);
152 static int template_parm_this_level_p (tree, void *);
153 static tree tsubst_friend_function (tree, tree);
154 static tree tsubst_friend_class (tree, tree);
155 static int can_complete_type_without_circularity (tree);
156 static tree get_bindings (tree, tree, tree, bool);
157 static int template_decl_level (tree);
158 static int check_cv_quals_for_unify (int, tree, tree);
159 static void template_parm_level_and_index (tree, int*, int*);
160 static int unify_pack_expansion (tree, tree, tree, tree, int, bool, bool);
161 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
162 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
163 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
164 static void regenerate_decl_from_template (tree, tree);
165 static tree most_specialized_class (tree, tree);
166 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
167 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
168 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
169 static bool check_specialization_scope (void);
170 static tree process_partial_specialization (tree);
171 static void set_current_access_from_decl (tree);
172 static tree get_template_base (tree, tree, tree, tree);
173 static tree try_class_unification (tree, tree, tree, tree);
174 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
176 static bool template_template_parm_bindings_ok_p (tree, tree);
177 static int template_args_equal (tree, tree);
178 static void tsubst_default_arguments (tree);
179 static tree for_each_template_parm_r (tree *, int *, void *);
180 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
181 static void copy_default_args_to_explicit_spec (tree);
182 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
183 static int eq_local_specializations (const void *, const void *);
184 static bool dependent_template_arg_p (tree);
185 static bool any_template_arguments_need_structural_equality_p (tree);
186 static bool dependent_type_p_r (tree);
187 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
188 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
189 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
190 static tree tsubst_decl (tree, tree, tsubst_flags_t);
191 static void perform_typedefs_access_check (tree tmpl, tree targs);
192 static void append_type_to_template_for_access_check_1 (tree, tree, tree);
193 static hashval_t iterative_hash_template_arg (tree arg, hashval_t val);
194 static bool primary_template_instantiation_p (const_tree);
195 static tree listify (tree);
196 static tree listify_autos (tree, tree);
198 /* Make the current scope suitable for access checking when we are
199 processing T. T can be FUNCTION_DECL for instantiated function
200 template, or VAR_DECL for static member variable (need by
201 instantiate_decl). */
204 push_access_scope (tree t)
206 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
207 || TREE_CODE (t) == VAR_DECL);
209 if (DECL_FRIEND_CONTEXT (t))
210 push_nested_class (DECL_FRIEND_CONTEXT (t));
211 else if (DECL_CLASS_SCOPE_P (t))
212 push_nested_class (DECL_CONTEXT (t));
214 push_to_top_level ();
216 if (TREE_CODE (t) == FUNCTION_DECL)
218 saved_access_scope = tree_cons
219 (NULL_TREE, current_function_decl, saved_access_scope);
220 current_function_decl = t;
224 /* Restore the scope set up by push_access_scope. T is the node we
228 pop_access_scope (tree t)
230 if (TREE_CODE (t) == FUNCTION_DECL)
232 current_function_decl = TREE_VALUE (saved_access_scope);
233 saved_access_scope = TREE_CHAIN (saved_access_scope);
236 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
239 pop_from_top_level ();
242 /* Do any processing required when DECL (a member template
243 declaration) is finished. Returns the TEMPLATE_DECL corresponding
244 to DECL, unless it is a specialization, in which case the DECL
245 itself is returned. */
248 finish_member_template_decl (tree decl)
250 if (decl == error_mark_node)
251 return error_mark_node;
253 gcc_assert (DECL_P (decl));
255 if (TREE_CODE (decl) == TYPE_DECL)
259 type = TREE_TYPE (decl);
260 if (type == error_mark_node)
261 return error_mark_node;
262 if (MAYBE_CLASS_TYPE_P (type)
263 && CLASSTYPE_TEMPLATE_INFO (type)
264 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
266 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
267 check_member_template (tmpl);
272 else if (TREE_CODE (decl) == FIELD_DECL)
273 error ("data member %qD cannot be a member template", decl);
274 else if (DECL_TEMPLATE_INFO (decl))
276 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
278 check_member_template (DECL_TI_TEMPLATE (decl));
279 return DECL_TI_TEMPLATE (decl);
285 error ("invalid member template declaration %qD", decl);
287 return error_mark_node;
290 /* Return the template info node corresponding to T, whatever T is. */
293 get_template_info (const_tree t)
295 tree tinfo = NULL_TREE;
297 if (!t || t == error_mark_node)
300 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
301 tinfo = DECL_TEMPLATE_INFO (t);
303 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
306 if (TAGGED_TYPE_P (t))
307 tinfo = TYPE_TEMPLATE_INFO (t);
312 /* Returns the template nesting level of the indicated class TYPE.
322 A<T>::B<U> has depth two, while A<T> has depth one.
323 Both A<T>::B<int> and A<int>::B<U> have depth one, if
324 they are instantiations, not specializations.
326 This function is guaranteed to return 0 if passed NULL_TREE so
327 that, for example, `template_class_depth (current_class_type)' is
331 template_class_depth (tree type)
336 type && TREE_CODE (type) != NAMESPACE_DECL;
337 type = (TREE_CODE (type) == FUNCTION_DECL)
338 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
340 tree tinfo = get_template_info (type);
342 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
343 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
350 /* Subroutine of maybe_begin_member_template_processing.
351 Returns true if processing DECL needs us to push template parms. */
354 inline_needs_template_parms (tree decl)
356 if (! DECL_TEMPLATE_INFO (decl))
359 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
360 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
363 /* Subroutine of maybe_begin_member_template_processing.
364 Push the template parms in PARMS, starting from LEVELS steps into the
365 chain, and ending at the beginning, since template parms are listed
369 push_inline_template_parms_recursive (tree parmlist, int levels)
371 tree parms = TREE_VALUE (parmlist);
375 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
377 ++processing_template_decl;
378 current_template_parms
379 = tree_cons (size_int (processing_template_decl),
380 parms, current_template_parms);
381 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
383 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
385 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
387 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
389 if (parm == error_mark_node)
392 gcc_assert (DECL_P (parm));
394 switch (TREE_CODE (parm))
403 /* Make a CONST_DECL as is done in process_template_parm.
404 It is ugly that we recreate this here; the original
405 version built in process_template_parm is no longer
407 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
408 CONST_DECL, DECL_NAME (parm),
410 DECL_ARTIFICIAL (decl) = 1;
411 TREE_CONSTANT (decl) = 1;
412 TREE_READONLY (decl) = 1;
413 DECL_INITIAL (decl) = DECL_INITIAL (parm);
414 SET_DECL_TEMPLATE_PARM_P (decl);
425 /* Restore the template parameter context for a member template or
426 a friend template defined in a class definition. */
429 maybe_begin_member_template_processing (tree decl)
434 if (inline_needs_template_parms (decl))
436 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
437 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
439 if (DECL_TEMPLATE_SPECIALIZATION (decl))
442 parms = TREE_CHAIN (parms);
445 push_inline_template_parms_recursive (parms, levels);
448 /* Remember how many levels of template parameters we pushed so that
449 we can pop them later. */
450 VEC_safe_push (int, heap, inline_parm_levels, levels);
453 /* Undo the effects of maybe_begin_member_template_processing. */
456 maybe_end_member_template_processing (void)
461 if (VEC_length (int, inline_parm_levels) == 0)
464 last = VEC_pop (int, inline_parm_levels);
465 for (i = 0; i < last; ++i)
467 --processing_template_decl;
468 current_template_parms = TREE_CHAIN (current_template_parms);
473 /* Return a new template argument vector which contains all of ARGS,
474 but has as its innermost set of arguments the EXTRA_ARGS. */
477 add_to_template_args (tree args, tree extra_args)
484 extra_depth = TMPL_ARGS_DEPTH (extra_args);
485 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
487 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
488 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
490 for (j = 1; j <= extra_depth; ++j, ++i)
491 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
496 /* Like add_to_template_args, but only the outermost ARGS are added to
497 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
498 (EXTRA_ARGS) levels are added. This function is used to combine
499 the template arguments from a partial instantiation with the
500 template arguments used to attain the full instantiation from the
501 partial instantiation. */
504 add_outermost_template_args (tree args, tree extra_args)
508 /* If there are more levels of EXTRA_ARGS than there are ARGS,
509 something very fishy is going on. */
510 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
512 /* If *all* the new arguments will be the EXTRA_ARGS, just return
514 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
517 /* For the moment, we make ARGS look like it contains fewer levels. */
518 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
520 new_args = add_to_template_args (args, extra_args);
522 /* Now, we restore ARGS to its full dimensions. */
523 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
528 /* Return the N levels of innermost template arguments from the ARGS. */
531 get_innermost_template_args (tree args, int n)
539 /* If N is 1, just return the innermost set of template arguments. */
541 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
543 /* If we're not removing anything, just return the arguments we were
545 extra_levels = TMPL_ARGS_DEPTH (args) - n;
546 gcc_assert (extra_levels >= 0);
547 if (extra_levels == 0)
550 /* Make a new set of arguments, not containing the outer arguments. */
551 new_args = make_tree_vec (n);
552 for (i = 1; i <= n; ++i)
553 SET_TMPL_ARGS_LEVEL (new_args, i,
554 TMPL_ARGS_LEVEL (args, i + extra_levels));
559 /* The inverse of get_innermost_template_args: Return all but the innermost
560 EXTRA_LEVELS levels of template arguments from the ARGS. */
563 strip_innermost_template_args (tree args, int extra_levels)
566 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
571 /* If N is 1, just return the outermost set of template arguments. */
573 return TMPL_ARGS_LEVEL (args, 1);
575 /* If we're not removing anything, just return the arguments we were
577 gcc_assert (extra_levels >= 0);
578 if (extra_levels == 0)
581 /* Make a new set of arguments, not containing the inner arguments. */
582 new_args = make_tree_vec (n);
583 for (i = 1; i <= n; ++i)
584 SET_TMPL_ARGS_LEVEL (new_args, i,
585 TMPL_ARGS_LEVEL (args, i));
590 /* We've got a template header coming up; push to a new level for storing
594 begin_template_parm_list (void)
596 /* We use a non-tag-transparent scope here, which causes pushtag to
597 put tags in this scope, rather than in the enclosing class or
598 namespace scope. This is the right thing, since we want
599 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
600 global template class, push_template_decl handles putting the
601 TEMPLATE_DECL into top-level scope. For a nested template class,
604 template <class T> struct S1 {
605 template <class T> struct S2 {};
608 pushtag contains special code to call pushdecl_with_scope on the
609 TEMPLATE_DECL for S2. */
610 begin_scope (sk_template_parms, NULL);
611 ++processing_template_decl;
612 ++processing_template_parmlist;
613 note_template_header (0);
616 /* This routine is called when a specialization is declared. If it is
617 invalid to declare a specialization here, an error is reported and
618 false is returned, otherwise this routine will return true. */
621 check_specialization_scope (void)
623 tree scope = current_scope ();
627 An explicit specialization shall be declared in the namespace of
628 which the template is a member, or, for member templates, in the
629 namespace of which the enclosing class or enclosing class
630 template is a member. An explicit specialization of a member
631 function, member class or static data member of a class template
632 shall be declared in the namespace of which the class template
634 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
636 error ("explicit specialization in non-namespace scope %qD", scope);
642 In an explicit specialization declaration for a member of a class
643 template or a member template that appears in namespace scope,
644 the member template and some of its enclosing class templates may
645 remain unspecialized, except that the declaration shall not
646 explicitly specialize a class member template if its enclosing
647 class templates are not explicitly specialized as well. */
648 if (current_template_parms)
650 error ("enclosing class templates are not explicitly specialized");
657 /* We've just seen template <>. */
660 begin_specialization (void)
662 begin_scope (sk_template_spec, NULL);
663 note_template_header (1);
664 return check_specialization_scope ();
667 /* Called at then end of processing a declaration preceded by
671 end_specialization (void)
674 reset_specialization ();
677 /* Any template <>'s that we have seen thus far are not referring to a
678 function specialization. */
681 reset_specialization (void)
683 processing_specialization = 0;
684 template_header_count = 0;
687 /* We've just seen a template header. If SPECIALIZATION is nonzero,
688 it was of the form template <>. */
691 note_template_header (int specialization)
693 processing_specialization = specialization;
694 template_header_count++;
697 /* We're beginning an explicit instantiation. */
700 begin_explicit_instantiation (void)
702 gcc_assert (!processing_explicit_instantiation);
703 processing_explicit_instantiation = true;
708 end_explicit_instantiation (void)
710 gcc_assert (processing_explicit_instantiation);
711 processing_explicit_instantiation = false;
714 /* An explicit specialization or partial specialization TMPL is being
715 declared. Check that the namespace in which the specialization is
716 occurring is permissible. Returns false iff it is invalid to
717 specialize TMPL in the current namespace. */
720 check_specialization_namespace (tree tmpl)
722 tree tpl_ns = decl_namespace_context (tmpl);
726 An explicit specialization shall be declared in the namespace of
727 which the template is a member, or, for member templates, in the
728 namespace of which the enclosing class or enclosing class
729 template is a member. An explicit specialization of a member
730 function, member class or static data member of a class template
731 shall be declared in the namespace of which the class template is
733 if (is_associated_namespace (current_namespace, tpl_ns))
734 /* Same or super-using namespace. */
738 permerror (input_location, "specialization of %qD in different namespace", tmpl);
739 permerror (input_location, " from definition of %q+#D", tmpl);
744 /* SPEC is an explicit instantiation. Check that it is valid to
745 perform this explicit instantiation in the current namespace. */
748 check_explicit_instantiation_namespace (tree spec)
752 /* DR 275: An explicit instantiation shall appear in an enclosing
753 namespace of its template. */
754 ns = decl_namespace_context (spec);
755 if (!is_ancestor (current_namespace, ns))
756 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
757 "(which does not enclose namespace %qD)",
758 spec, current_namespace, ns);
761 /* The TYPE is being declared. If it is a template type, that means it
762 is a partial specialization. Do appropriate error-checking. */
765 maybe_process_partial_specialization (tree type)
769 if (type == error_mark_node)
770 return error_mark_node;
772 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
774 error ("name of class shadows template template parameter %qD",
776 return error_mark_node;
779 context = TYPE_CONTEXT (type);
781 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
783 /* This is for ordinary explicit specialization and partial
784 specialization of a template class such as:
786 template <> class C<int>;
790 template <class T> class C<T*>;
792 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
794 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
795 && !COMPLETE_TYPE_P (type))
797 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
798 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
799 if (processing_template_decl)
801 if (push_template_decl (TYPE_MAIN_DECL (type))
803 return error_mark_node;
806 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
807 error ("specialization of %qT after instantiation", type);
809 else if (CLASS_TYPE_P (type)
810 && !CLASSTYPE_USE_TEMPLATE (type)
811 && CLASSTYPE_TEMPLATE_INFO (type)
812 && context && CLASS_TYPE_P (context)
813 && CLASSTYPE_TEMPLATE_INFO (context))
815 /* This is for an explicit specialization of member class
816 template according to [temp.expl.spec/18]:
818 template <> template <class U> class C<int>::D;
820 The context `C<int>' must be an implicit instantiation.
821 Otherwise this is just a member class template declared
824 template <> class C<int> { template <class U> class D; };
825 template <> template <class U> class C<int>::D;
827 In the first case, `C<int>::D' is a specialization of `C<T>::D'
828 while in the second case, `C<int>::D' is a primary template
829 and `C<T>::D' may not exist. */
831 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
832 && !COMPLETE_TYPE_P (type))
835 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
837 if (current_namespace
838 != decl_namespace_context (tmpl))
840 permerror (input_location, "specializing %q#T in different namespace", type);
841 permerror (input_location, " from definition of %q+#D", tmpl);
844 /* Check for invalid specialization after instantiation:
846 template <> template <> class C<int>::D<int>;
847 template <> template <class U> class C<int>::D; */
849 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
850 t; t = TREE_CHAIN (t))
852 tree inst = TREE_VALUE (t);
853 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
855 /* We already have a full specialization of this partial
856 instantiation. Reassign it to the new member
857 specialization template. */
861 elt.tmpl = most_general_template (tmpl);
862 elt.args = CLASSTYPE_TI_ARGS (inst);
865 htab_remove_elt (type_specializations, &elt);
868 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
870 slot = (spec_entry **)
871 htab_find_slot (type_specializations, &elt, INSERT);
872 *slot = GGC_NEW (spec_entry);
875 else if (COMPLETE_TYPE_P (inst) || TYPE_BEING_DEFINED (inst))
876 /* But if we've had an implicit instantiation, that's a
877 problem ([temp.expl.spec]/6). */
878 error ("specialization %qT after instantiation %qT",
882 /* Mark TYPE as a specialization. And as a result, we only
883 have one level of template argument for the innermost
885 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
886 CLASSTYPE_TI_ARGS (type)
887 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
890 else if (processing_specialization)
892 error ("explicit specialization of non-template %qT", type);
893 return error_mark_node;
899 /* Returns nonzero if we can optimize the retrieval of specializations
900 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
901 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
904 optimize_specialization_lookup_p (tree tmpl)
906 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
907 && DECL_CLASS_SCOPE_P (tmpl)
908 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
910 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
911 /* The optimized lookup depends on the fact that the
912 template arguments for the member function template apply
913 purely to the containing class, which is not true if the
914 containing class is an explicit or partial
916 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
917 && !DECL_MEMBER_TEMPLATE_P (tmpl)
918 && !DECL_CONV_FN_P (tmpl)
919 /* It is possible to have a template that is not a member
920 template and is not a member of a template class:
922 template <typename T>
923 struct S { friend A::f(); };
925 Here, the friend function is a template, but the context does
926 not have template information. The optimized lookup relies
927 on having ARGS be the template arguments for both the class
928 and the function template. */
929 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
932 /* Retrieve the specialization (in the sense of [temp.spec] - a
933 specialization is either an instantiation or an explicit
934 specialization) of TMPL for the given template ARGS. If there is
935 no such specialization, return NULL_TREE. The ARGS are a vector of
936 arguments, or a vector of vectors of arguments, in the case of
937 templates with more than one level of parameters.
939 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
940 then we search for a partial specialization matching ARGS. This
941 parameter is ignored if TMPL is not a class template. */
944 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
946 if (args == error_mark_node)
949 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
951 /* There should be as many levels of arguments as there are
952 levels of parameters. */
953 gcc_assert (TMPL_ARGS_DEPTH (args)
954 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
956 if (optimize_specialization_lookup_p (tmpl))
959 tree class_specialization;
960 VEC(tree,gc) *methods;
964 /* The template arguments actually apply to the containing
965 class. Find the class specialization with those
967 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
969 = retrieve_specialization (class_template, args, 0);
970 if (!class_specialization)
972 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
973 for the specialization. */
974 idx = class_method_index_for_fn (class_specialization, tmpl);
977 /* Iterate through the methods with the indicated name, looking
978 for the one that has an instance of TMPL. */
979 methods = CLASSTYPE_METHOD_VEC (class_specialization);
980 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
982 tree fn = OVL_CURRENT (fns);
983 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
984 /* using-declarations can add base methods to the method vec,
985 and we don't want those here. */
986 && DECL_CONTEXT (fn) == class_specialization)
995 htab_t specializations;
999 elt.spec = NULL_TREE;
1001 if (DECL_CLASS_TEMPLATE_P (tmpl))
1002 specializations = type_specializations;
1004 specializations = decl_specializations;
1007 hash = hash_specialization (&elt);
1008 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1016 /* Like retrieve_specialization, but for local declarations. */
1019 retrieve_local_specialization (tree tmpl)
1023 if (local_specializations == NULL)
1026 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1027 htab_hash_pointer (tmpl));
1028 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1031 /* Returns nonzero iff DECL is a specialization of TMPL. */
1034 is_specialization_of (tree decl, tree tmpl)
1038 if (TREE_CODE (decl) == FUNCTION_DECL)
1042 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1048 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1050 for (t = TREE_TYPE (decl);
1052 t = CLASSTYPE_USE_TEMPLATE (t)
1053 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1054 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1061 /* Returns nonzero iff DECL is a specialization of friend declaration
1062 FRIEND_DECL according to [temp.friend]. */
1065 is_specialization_of_friend (tree decl, tree friend_decl)
1067 bool need_template = true;
1070 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1071 || TREE_CODE (decl) == TYPE_DECL);
1073 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1074 of a template class, we want to check if DECL is a specialization
1076 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1077 && DECL_TEMPLATE_INFO (friend_decl)
1078 && !DECL_USE_TEMPLATE (friend_decl))
1080 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1081 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1082 need_template = false;
1084 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1085 && !PRIMARY_TEMPLATE_P (friend_decl))
1086 need_template = false;
1088 /* There is nothing to do if this is not a template friend. */
1089 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1092 if (is_specialization_of (decl, friend_decl))
1096 A member of a class template may be declared to be a friend of a
1097 non-template class. In this case, the corresponding member of
1098 every specialization of the class template is a friend of the
1099 class granting friendship.
1101 For example, given a template friend declaration
1103 template <class T> friend void A<T>::f();
1105 the member function below is considered a friend
1107 template <> struct A<int> {
1111 For this type of template friend, TEMPLATE_DEPTH below will be
1112 nonzero. To determine if DECL is a friend of FRIEND, we first
1113 check if the enclosing class is a specialization of another. */
1115 template_depth = template_class_depth (DECL_CONTEXT (friend_decl));
1117 && DECL_CLASS_SCOPE_P (decl)
1118 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1119 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1121 /* Next, we check the members themselves. In order to handle
1122 a few tricky cases, such as when FRIEND_DECL's are
1124 template <class T> friend void A<T>::g(T t);
1125 template <class T> template <T t> friend void A<T>::h();
1129 void A<int>::g(int);
1130 template <int> void A<int>::h();
1132 we need to figure out ARGS, the template arguments from
1133 the context of DECL. This is required for template substitution
1134 of `T' in the function parameter of `g' and template parameter
1135 of `h' in the above examples. Here ARGS corresponds to `int'. */
1137 tree context = DECL_CONTEXT (decl);
1138 tree args = NULL_TREE;
1139 int current_depth = 0;
1141 while (current_depth < template_depth)
1143 if (CLASSTYPE_TEMPLATE_INFO (context))
1145 if (current_depth == 0)
1146 args = TYPE_TI_ARGS (context);
1148 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1151 context = TYPE_CONTEXT (context);
1154 if (TREE_CODE (decl) == FUNCTION_DECL)
1159 tree friend_args_type;
1160 tree decl_args_type;
1162 /* Make sure that both DECL and FRIEND_DECL are templates or
1164 is_template = DECL_TEMPLATE_INFO (decl)
1165 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1166 if (need_template ^ is_template)
1168 else if (is_template)
1170 /* If both are templates, check template parameter list. */
1172 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1174 if (!comp_template_parms
1175 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1179 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1182 decl_type = TREE_TYPE (decl);
1184 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1185 tf_none, NULL_TREE);
1186 if (friend_type == error_mark_node)
1189 /* Check if return types match. */
1190 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1193 /* Check if function parameter types match, ignoring the
1194 `this' parameter. */
1195 friend_args_type = TYPE_ARG_TYPES (friend_type);
1196 decl_args_type = TYPE_ARG_TYPES (decl_type);
1197 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1198 friend_args_type = TREE_CHAIN (friend_args_type);
1199 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1200 decl_args_type = TREE_CHAIN (decl_args_type);
1202 return compparms (decl_args_type, friend_args_type);
1206 /* DECL is a TYPE_DECL */
1208 tree decl_type = TREE_TYPE (decl);
1210 /* Make sure that both DECL and FRIEND_DECL are templates or
1213 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1214 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1216 if (need_template ^ is_template)
1218 else if (is_template)
1221 /* If both are templates, check the name of the two
1222 TEMPLATE_DECL's first because is_friend didn't. */
1223 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1224 != DECL_NAME (friend_decl))
1227 /* Now check template parameter list. */
1229 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1231 return comp_template_parms
1232 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1236 return (DECL_NAME (decl)
1237 == DECL_NAME (friend_decl));
1243 /* Register the specialization SPEC as a specialization of TMPL with
1244 the indicated ARGS. IS_FRIEND indicates whether the specialization
1245 is actually just a friend declaration. Returns SPEC, or an
1246 equivalent prior declaration, if available. */
1249 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1253 spec_entry **slot = NULL;
1256 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1258 if (TREE_CODE (spec) == FUNCTION_DECL
1259 && uses_template_parms (DECL_TI_ARGS (spec)))
1260 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1261 register it; we want the corresponding TEMPLATE_DECL instead.
1262 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1263 the more obvious `uses_template_parms (spec)' to avoid problems
1264 with default function arguments. In particular, given
1265 something like this:
1267 template <class T> void f(T t1, T t = T())
1269 the default argument expression is not substituted for in an
1270 instantiation unless and until it is actually needed. */
1273 if (optimize_specialization_lookup_p (tmpl))
1274 /* We don't put these specializations in the hash table, but we might
1275 want to give an error about a mismatch. */
1276 fn = retrieve_specialization (tmpl, args, 0);
1284 hash = hash_specialization (&elt);
1286 slot = (spec_entry **)
1287 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1294 /* We can sometimes try to re-register a specialization that we've
1295 already got. In particular, regenerate_decl_from_template calls
1296 duplicate_decls which will update the specialization list. But,
1297 we'll still get called again here anyhow. It's more convenient
1298 to simply allow this than to try to prevent it. */
1301 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1303 if (DECL_TEMPLATE_INSTANTIATION (fn))
1305 if (DECL_ODR_USED (fn)
1306 || DECL_EXPLICIT_INSTANTIATION (fn))
1308 error ("specialization of %qD after instantiation",
1310 return error_mark_node;
1315 /* This situation should occur only if the first
1316 specialization is an implicit instantiation, the
1317 second is an explicit specialization, and the
1318 implicit instantiation has not yet been used. That
1319 situation can occur if we have implicitly
1320 instantiated a member function and then specialized
1323 We can also wind up here if a friend declaration that
1324 looked like an instantiation turns out to be a
1327 template <class T> void foo(T);
1328 class S { friend void foo<>(int) };
1329 template <> void foo(int);
1331 We transform the existing DECL in place so that any
1332 pointers to it become pointers to the updated
1335 If there was a definition for the template, but not
1336 for the specialization, we want this to look as if
1337 there were no definition, and vice versa. */
1338 DECL_INITIAL (fn) = NULL_TREE;
1339 duplicate_decls (spec, fn, is_friend);
1340 /* The call to duplicate_decls will have applied
1343 An explicit specialization of a function template
1344 is inline only if it is explicitly declared to be,
1345 and independently of whether its function template
1348 to the primary function; now copy the inline bits to
1349 the various clones. */
1350 FOR_EACH_CLONE (clone, fn)
1352 DECL_DECLARED_INLINE_P (clone)
1353 = DECL_DECLARED_INLINE_P (fn);
1354 DECL_SOURCE_LOCATION (clone)
1355 = DECL_SOURCE_LOCATION (fn);
1357 check_specialization_namespace (fn);
1362 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1364 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1365 /* Dup decl failed, but this is a new definition. Set the
1366 line number so any errors match this new
1368 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1374 return duplicate_decls (spec, fn, is_friend);
1376 /* A specialization must be declared in the same namespace as the
1377 template it is specializing. */
1378 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1379 && !check_specialization_namespace (tmpl))
1380 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1382 if (!optimize_specialization_lookup_p (tmpl))
1384 gcc_assert (tmpl && args && spec);
1385 *slot = GGC_NEW (spec_entry);
1387 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1388 && PRIMARY_TEMPLATE_P (tmpl)
1389 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1390 /* TMPL is a forward declaration of a template function; keep a list
1391 of all specializations in case we need to reassign them to a friend
1392 template later in tsubst_friend_function. */
1393 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1394 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1400 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1401 TMPL and ARGS members, ignores SPEC. */
1404 eq_specializations (const void *p1, const void *p2)
1406 const spec_entry *e1 = (const spec_entry *)p1;
1407 const spec_entry *e2 = (const spec_entry *)p2;
1409 return (e1->tmpl == e2->tmpl
1410 && comp_template_args (e1->args, e2->args));
1413 /* Returns a hash for a template TMPL and template arguments ARGS. */
1416 hash_tmpl_and_args (tree tmpl, tree args)
1418 hashval_t val = DECL_UID (tmpl);
1419 return iterative_hash_template_arg (args, val);
1422 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1426 hash_specialization (const void *p)
1428 const spec_entry *e = (const spec_entry *)p;
1429 return hash_tmpl_and_args (e->tmpl, e->args);
1432 /* Recursively calculate a hash value for a template argument ARG, for use
1433 in the hash tables of template specializations. */
1436 iterative_hash_template_arg (tree arg, hashval_t val)
1438 unsigned HOST_WIDE_INT i;
1439 enum tree_code code;
1442 if (arg == NULL_TREE)
1443 return iterative_hash_object (arg, val);
1448 code = TREE_CODE (arg);
1449 tclass = TREE_CODE_CLASS (code);
1451 val = iterative_hash_object (code, val);
1458 case IDENTIFIER_NODE:
1459 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1463 int i, len = TREE_VEC_LENGTH (arg);
1464 for (i = 0; i < len; ++i)
1465 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1469 case TYPE_PACK_EXPANSION:
1470 case EXPR_PACK_EXPANSION:
1471 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1473 case ARGUMENT_PACK_SELECT:
1474 /* We can get one of these when re-hashing a previous entry in the middle
1475 of substituting into a pack expansion. Just look through it... */
1476 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1477 /* ...and fall through. */
1478 case TYPE_ARGUMENT_PACK:
1479 case NONTYPE_ARGUMENT_PACK:
1480 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1483 for (; arg; arg = TREE_CHAIN (arg))
1484 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1488 for (; arg; arg = OVL_CHAIN (arg))
1489 val = iterative_hash_template_arg (OVL_FUNCTION (arg), val);
1495 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1497 val = iterative_hash_template_arg (field, val);
1498 val = iterative_hash_template_arg (value, val);
1504 if (!DECL_ARTIFICIAL (arg))
1505 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1506 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1509 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1512 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1513 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1515 case TEMPLATE_PARM_INDEX:
1516 val = iterative_hash_template_arg
1517 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1518 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1519 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1522 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1523 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1524 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1527 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1529 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1533 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1534 code = TREE_CODE (TREE_OPERAND (arg, 1));
1535 val = iterative_hash_object (code, val);
1536 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1542 if (TYPE_CANONICAL (arg))
1543 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1545 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1546 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1547 /* Otherwise just compare the types during lookup. */
1550 case tcc_declaration:
1552 return iterative_hash_expr (arg, val);
1555 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1557 unsigned n = TREE_OPERAND_LENGTH (arg);
1558 for (i = 0; i < n; ++i)
1559 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1568 /* Unregister the specialization SPEC as a specialization of TMPL.
1569 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1570 if the SPEC was listed as a specialization of TMPL.
1572 Note that SPEC has been ggc_freed, so we can't look inside it. */
1575 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1580 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1581 elt.args = TI_ARGS (tinfo);
1582 elt.spec = NULL_TREE;
1584 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1587 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1588 gcc_assert (new_spec != NULL_TREE);
1589 (*slot)->spec = new_spec;
1596 /* Compare an entry in the local specializations hash table P1 (which
1597 is really a pointer to a TREE_LIST) with P2 (which is really a
1601 eq_local_specializations (const void *p1, const void *p2)
1603 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1606 /* Hash P1, an entry in the local specializations table. */
1609 hash_local_specialization (const void* p1)
1611 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1614 /* Like register_specialization, but for local declarations. We are
1615 registering SPEC, an instantiation of TMPL. */
1618 register_local_specialization (tree spec, tree tmpl)
1622 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1623 htab_hash_pointer (tmpl), INSERT);
1624 *slot = build_tree_list (spec, tmpl);
1627 /* TYPE is a class type. Returns true if TYPE is an explicitly
1628 specialized class. */
1631 explicit_class_specialization_p (tree type)
1633 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1635 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1638 /* Print the list of candidate FNS in an error message. */
1641 print_candidates (tree fns)
1646 const char *str = "candidates are:";
1648 if (is_overloaded_fn (fns))
1650 for (f = fns; f; f = OVL_NEXT (f))
1652 error ("%s %+#D", str, OVL_CURRENT (f));
1656 else for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1658 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1659 error ("%s %+#D", str, OVL_CURRENT (f));
1664 /* Returns the template (one of the functions given by TEMPLATE_ID)
1665 which can be specialized to match the indicated DECL with the
1666 explicit template args given in TEMPLATE_ID. The DECL may be
1667 NULL_TREE if none is available. In that case, the functions in
1668 TEMPLATE_ID are non-members.
1670 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1671 specialization of a member template.
1673 The TEMPLATE_COUNT is the number of references to qualifying
1674 template classes that appeared in the name of the function. See
1675 check_explicit_specialization for a more accurate description.
1677 TSK indicates what kind of template declaration (if any) is being
1678 declared. TSK_TEMPLATE indicates that the declaration given by
1679 DECL, though a FUNCTION_DECL, has template parameters, and is
1680 therefore a template function.
1682 The template args (those explicitly specified and those deduced)
1683 are output in a newly created vector *TARGS_OUT.
1685 If it is impossible to determine the result, an error message is
1686 issued. The error_mark_node is returned to indicate failure. */
1689 determine_specialization (tree template_id,
1692 int need_member_template,
1698 tree explicit_targs;
1699 tree candidates = NULL_TREE;
1700 /* A TREE_LIST of templates of which DECL may be a specialization.
1701 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1702 corresponding TREE_PURPOSE is the set of template arguments that,
1703 when used to instantiate the template, would produce a function
1704 with the signature of DECL. */
1705 tree templates = NULL_TREE;
1707 struct cp_binding_level *b;
1709 *targs_out = NULL_TREE;
1711 if (template_id == error_mark_node || decl == error_mark_node)
1712 return error_mark_node;
1714 fns = TREE_OPERAND (template_id, 0);
1715 explicit_targs = TREE_OPERAND (template_id, 1);
1717 if (fns == error_mark_node)
1718 return error_mark_node;
1720 /* Check for baselinks. */
1721 if (BASELINK_P (fns))
1722 fns = BASELINK_FUNCTIONS (fns);
1724 if (!is_overloaded_fn (fns))
1726 error ("%qD is not a function template", fns);
1727 return error_mark_node;
1730 /* Count the number of template headers specified for this
1733 for (b = current_binding_level;
1734 b->kind == sk_template_parms;
1738 for (; fns; fns = OVL_NEXT (fns))
1740 tree fn = OVL_CURRENT (fns);
1742 if (TREE_CODE (fn) == TEMPLATE_DECL)
1744 tree decl_arg_types;
1747 /* In case of explicit specialization, we need to check if
1748 the number of template headers appearing in the specialization
1749 is correct. This is usually done in check_explicit_specialization,
1750 but the check done there cannot be exhaustive when specializing
1751 member functions. Consider the following code:
1753 template <> void A<int>::f(int);
1754 template <> template <> void A<int>::f(int);
1756 Assuming that A<int> is not itself an explicit specialization
1757 already, the first line specializes "f" which is a non-template
1758 member function, whilst the second line specializes "f" which
1759 is a template member function. So both lines are syntactically
1760 correct, and check_explicit_specialization does not reject
1763 Here, we can do better, as we are matching the specialization
1764 against the declarations. We count the number of template
1765 headers, and we check if they match TEMPLATE_COUNT + 1
1766 (TEMPLATE_COUNT is the number of qualifying template classes,
1767 plus there must be another header for the member template
1770 Notice that if header_count is zero, this is not a
1771 specialization but rather a template instantiation, so there
1772 is no check we can perform here. */
1773 if (header_count && header_count != template_count + 1)
1776 /* Check that the number of template arguments at the
1777 innermost level for DECL is the same as for FN. */
1778 if (current_binding_level->kind == sk_template_parms
1779 && !current_binding_level->explicit_spec_p
1780 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1781 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1782 (current_template_parms))))
1785 /* DECL might be a specialization of FN. */
1786 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1787 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1789 /* For a non-static member function, we need to make sure
1790 that the const qualification is the same. Since
1791 get_bindings does not try to merge the "this" parameter,
1792 we must do the comparison explicitly. */
1793 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1794 && !same_type_p (TREE_VALUE (fn_arg_types),
1795 TREE_VALUE (decl_arg_types)))
1798 /* Skip the "this" parameter and, for constructors of
1799 classes with virtual bases, the VTT parameter. A
1800 full specialization of a constructor will have a VTT
1801 parameter, but a template never will. */
1803 = skip_artificial_parms_for (decl, decl_arg_types);
1805 = skip_artificial_parms_for (fn, fn_arg_types);
1807 /* Check that the number of function parameters matches.
1809 template <class T> void f(int i = 0);
1810 template <> void f<int>();
1811 The specialization f<int> is invalid but is not caught
1812 by get_bindings below. */
1813 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1816 /* Function templates cannot be specializations; there are
1817 no partial specializations of functions. Therefore, if
1818 the type of DECL does not match FN, there is no
1820 if (tsk == tsk_template)
1822 if (compparms (fn_arg_types, decl_arg_types))
1823 candidates = tree_cons (NULL_TREE, fn, candidates);
1827 /* See whether this function might be a specialization of this
1829 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1832 /* We cannot deduce template arguments that when used to
1833 specialize TMPL will produce DECL. */
1836 /* Save this template, and the arguments deduced. */
1837 templates = tree_cons (targs, fn, templates);
1839 else if (need_member_template)
1840 /* FN is an ordinary member function, and we need a
1841 specialization of a member template. */
1843 else if (TREE_CODE (fn) != FUNCTION_DECL)
1844 /* We can get IDENTIFIER_NODEs here in certain erroneous
1847 else if (!DECL_FUNCTION_MEMBER_P (fn))
1848 /* This is just an ordinary non-member function. Nothing can
1849 be a specialization of that. */
1851 else if (DECL_ARTIFICIAL (fn))
1852 /* Cannot specialize functions that are created implicitly. */
1856 tree decl_arg_types;
1858 /* This is an ordinary member function. However, since
1859 we're here, we can assume it's enclosing class is a
1860 template class. For example,
1862 template <typename T> struct S { void f(); };
1863 template <> void S<int>::f() {}
1865 Here, S<int>::f is a non-template, but S<int> is a
1866 template class. If FN has the same type as DECL, we
1867 might be in business. */
1869 if (!DECL_TEMPLATE_INFO (fn))
1870 /* Its enclosing class is an explicit specialization
1871 of a template class. This is not a candidate. */
1874 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1875 TREE_TYPE (TREE_TYPE (fn))))
1876 /* The return types differ. */
1879 /* Adjust the type of DECL in case FN is a static member. */
1880 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1881 if (DECL_STATIC_FUNCTION_P (fn)
1882 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1883 decl_arg_types = TREE_CHAIN (decl_arg_types);
1885 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1888 candidates = tree_cons (NULL_TREE, fn, candidates);
1892 if (templates && TREE_CHAIN (templates))
1898 It is possible for a specialization with a given function
1899 signature to be instantiated from more than one function
1900 template. In such cases, explicit specification of the
1901 template arguments must be used to uniquely identify the
1902 function template specialization being specialized.
1904 Note that here, there's no suggestion that we're supposed to
1905 determine which of the candidate templates is most
1906 specialized. However, we, also have:
1910 Partial ordering of overloaded function template
1911 declarations is used in the following contexts to select
1912 the function template to which a function template
1913 specialization refers:
1915 -- when an explicit specialization refers to a function
1918 So, we do use the partial ordering rules, at least for now.
1919 This extension can only serve to make invalid programs valid,
1920 so it's safe. And, there is strong anecdotal evidence that
1921 the committee intended the partial ordering rules to apply;
1922 the EDG front end has that behavior, and John Spicer claims
1923 that the committee simply forgot to delete the wording in
1924 [temp.expl.spec]. */
1925 tree tmpl = most_specialized_instantiation (templates);
1926 if (tmpl != error_mark_node)
1929 TREE_CHAIN (templates) = NULL_TREE;
1933 if (templates == NULL_TREE && candidates == NULL_TREE)
1935 error ("template-id %qD for %q+D does not match any template "
1936 "declaration", template_id, decl);
1937 return error_mark_node;
1939 else if ((templates && TREE_CHAIN (templates))
1940 || (candidates && TREE_CHAIN (candidates))
1941 || (templates && candidates))
1943 error ("ambiguous template specialization %qD for %q+D",
1945 chainon (candidates, templates);
1946 print_candidates (candidates);
1947 return error_mark_node;
1950 /* We have one, and exactly one, match. */
1953 tree fn = TREE_VALUE (candidates);
1954 *targs_out = copy_node (DECL_TI_ARGS (fn));
1955 /* DECL is a re-declaration or partial instantiation of a template
1957 if (TREE_CODE (fn) == TEMPLATE_DECL)
1959 /* It was a specialization of an ordinary member function in a
1961 return DECL_TI_TEMPLATE (fn);
1964 /* It was a specialization of a template. */
1965 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1966 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1968 *targs_out = copy_node (targs);
1969 SET_TMPL_ARGS_LEVEL (*targs_out,
1970 TMPL_ARGS_DEPTH (*targs_out),
1971 TREE_PURPOSE (templates));
1974 *targs_out = TREE_PURPOSE (templates);
1975 return TREE_VALUE (templates);
1978 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1979 but with the default argument values filled in from those in the
1983 copy_default_args_to_explicit_spec_1 (tree spec_types,
1986 tree new_spec_types;
1991 if (spec_types == void_list_node)
1992 return void_list_node;
1994 /* Substitute into the rest of the list. */
1996 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1997 TREE_CHAIN (tmpl_types));
1999 /* Add the default argument for this parameter. */
2000 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2001 TREE_VALUE (spec_types),
2005 /* DECL is an explicit specialization. Replicate default arguments
2006 from the template it specializes. (That way, code like:
2008 template <class T> void f(T = 3);
2009 template <> void f(double);
2012 works, as required.) An alternative approach would be to look up
2013 the correct default arguments at the call-site, but this approach
2014 is consistent with how implicit instantiations are handled. */
2017 copy_default_args_to_explicit_spec (tree decl)
2022 tree new_spec_types;
2026 tree object_type = NULL_TREE;
2027 tree in_charge = NULL_TREE;
2028 tree vtt = NULL_TREE;
2030 /* See if there's anything we need to do. */
2031 tmpl = DECL_TI_TEMPLATE (decl);
2032 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2033 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2034 if (TREE_PURPOSE (t))
2039 old_type = TREE_TYPE (decl);
2040 spec_types = TYPE_ARG_TYPES (old_type);
2042 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2044 /* Remove the this pointer, but remember the object's type for
2046 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2047 spec_types = TREE_CHAIN (spec_types);
2048 tmpl_types = TREE_CHAIN (tmpl_types);
2050 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2052 /* DECL may contain more parameters than TMPL due to the extra
2053 in-charge parameter in constructors and destructors. */
2054 in_charge = spec_types;
2055 spec_types = TREE_CHAIN (spec_types);
2057 if (DECL_HAS_VTT_PARM_P (decl))
2060 spec_types = TREE_CHAIN (spec_types);
2064 /* Compute the merged default arguments. */
2066 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2068 /* Compute the new FUNCTION_TYPE. */
2072 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2077 /* Put the in-charge parameter back. */
2078 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2079 TREE_VALUE (in_charge),
2082 new_type = build_method_type_directly (object_type,
2083 TREE_TYPE (old_type),
2087 new_type = build_function_type (TREE_TYPE (old_type),
2089 new_type = cp_build_type_attribute_variant (new_type,
2090 TYPE_ATTRIBUTES (old_type));
2091 new_type = build_exception_variant (new_type,
2092 TYPE_RAISES_EXCEPTIONS (old_type));
2093 TREE_TYPE (decl) = new_type;
2096 /* Check to see if the function just declared, as indicated in
2097 DECLARATOR, and in DECL, is a specialization of a function
2098 template. We may also discover that the declaration is an explicit
2099 instantiation at this point.
2101 Returns DECL, or an equivalent declaration that should be used
2102 instead if all goes well. Issues an error message if something is
2103 amiss. Returns error_mark_node if the error is not easily
2106 FLAGS is a bitmask consisting of the following flags:
2108 2: The function has a definition.
2109 4: The function is a friend.
2111 The TEMPLATE_COUNT is the number of references to qualifying
2112 template classes that appeared in the name of the function. For
2115 template <class T> struct S { void f(); };
2118 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2119 classes are not counted in the TEMPLATE_COUNT, so that in
2121 template <class T> struct S {};
2122 template <> struct S<int> { void f(); }
2123 template <> void S<int>::f();
2125 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2126 invalid; there should be no template <>.)
2128 If the function is a specialization, it is marked as such via
2129 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2130 is set up correctly, and it is added to the list of specializations
2131 for that template. */
2134 check_explicit_specialization (tree declarator,
2139 int have_def = flags & 2;
2140 int is_friend = flags & 4;
2141 int specialization = 0;
2142 int explicit_instantiation = 0;
2143 int member_specialization = 0;
2144 tree ctype = DECL_CLASS_CONTEXT (decl);
2145 tree dname = DECL_NAME (decl);
2150 if (!processing_specialization)
2153 tsk = tsk_excessive_parms;
2156 tsk = current_tmpl_spec_kind (template_count);
2161 if (processing_specialization)
2164 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2166 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2169 /* This could be something like:
2171 template <class T> void f(T);
2172 class S { friend void f<>(int); } */
2176 /* This case handles bogus declarations like template <>
2177 template <class T> void f<int>(); */
2179 error ("template-id %qD in declaration of primary template",
2186 case tsk_invalid_member_spec:
2187 /* The error has already been reported in
2188 check_specialization_scope. */
2189 return error_mark_node;
2191 case tsk_invalid_expl_inst:
2192 error ("template parameter list used in explicit instantiation");
2198 error ("definition provided for explicit instantiation");
2200 explicit_instantiation = 1;
2203 case tsk_excessive_parms:
2204 case tsk_insufficient_parms:
2205 if (tsk == tsk_excessive_parms)
2206 error ("too many template parameter lists in declaration of %qD",
2208 else if (template_header_count)
2209 error("too few template parameter lists in declaration of %qD", decl);
2211 error("explicit specialization of %qD must be introduced by "
2212 "%<template <>%>", decl);
2216 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2218 member_specialization = 1;
2224 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2226 /* This case handles bogus declarations like template <>
2227 template <class T> void f<int>(); */
2229 if (uses_template_parms (declarator))
2230 error ("function template partial specialization %qD "
2231 "is not allowed", declarator);
2233 error ("template-id %qD in declaration of primary template",
2238 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2239 /* This is a specialization of a member template, without
2240 specialization the containing class. Something like:
2242 template <class T> struct S {
2243 template <class U> void f (U);
2245 template <> template <class U> void S<int>::f(U) {}
2247 That's a specialization -- but of the entire template. */
2255 if (specialization || member_specialization)
2257 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2258 for (; t; t = TREE_CHAIN (t))
2259 if (TREE_PURPOSE (t))
2261 permerror (input_location,
2262 "default argument specified in explicit specialization");
2267 if (specialization || member_specialization || explicit_instantiation)
2269 tree tmpl = NULL_TREE;
2270 tree targs = NULL_TREE;
2272 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2273 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2277 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2282 /* If there is no class context, the explicit instantiation
2283 must be at namespace scope. */
2284 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2286 /* Find the namespace binding, using the declaration
2288 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2290 if (fns == error_mark_node || !is_overloaded_fn (fns))
2292 error ("%qD is not a template function", dname);
2293 fns = error_mark_node;
2297 tree fn = OVL_CURRENT (fns);
2298 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2299 CP_DECL_CONTEXT (fn)))
2300 error ("%qD is not declared in %qD",
2301 decl, current_namespace);
2305 declarator = lookup_template_function (fns, NULL_TREE);
2308 if (declarator == error_mark_node)
2309 return error_mark_node;
2311 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2313 if (!explicit_instantiation)
2314 /* A specialization in class scope. This is invalid,
2315 but the error will already have been flagged by
2316 check_specialization_scope. */
2317 return error_mark_node;
2320 /* It's not valid to write an explicit instantiation in
2323 class C { template void f(); }
2325 This case is caught by the parser. However, on
2328 template class C { void f(); };
2330 (which is invalid) we can get here. The error will be
2337 else if (ctype != NULL_TREE
2338 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2341 /* Find the list of functions in ctype that have the same
2342 name as the declared function. */
2343 tree name = TREE_OPERAND (declarator, 0);
2344 tree fns = NULL_TREE;
2347 if (constructor_name_p (name, ctype))
2349 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2351 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2352 : !CLASSTYPE_DESTRUCTORS (ctype))
2354 /* From [temp.expl.spec]:
2356 If such an explicit specialization for the member
2357 of a class template names an implicitly-declared
2358 special member function (clause _special_), the
2359 program is ill-formed.
2361 Similar language is found in [temp.explicit]. */
2362 error ("specialization of implicitly-declared special member function");
2363 return error_mark_node;
2366 name = is_constructor ? ctor_identifier : dtor_identifier;
2369 if (!DECL_CONV_FN_P (decl))
2371 idx = lookup_fnfields_1 (ctype, name);
2373 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2377 VEC(tree,gc) *methods;
2380 /* For a type-conversion operator, we cannot do a
2381 name-based lookup. We might be looking for `operator
2382 int' which will be a specialization of `operator T'.
2383 So, we find *all* the conversion operators, and then
2384 select from them. */
2387 methods = CLASSTYPE_METHOD_VEC (ctype);
2389 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2390 VEC_iterate (tree, methods, idx, ovl);
2393 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2394 /* There are no more conversion functions. */
2397 /* Glue all these conversion functions together
2398 with those we already have. */
2399 for (; ovl; ovl = OVL_NEXT (ovl))
2400 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2404 if (fns == NULL_TREE)
2406 error ("no member function %qD declared in %qT", name, ctype);
2407 return error_mark_node;
2410 TREE_OPERAND (declarator, 0) = fns;
2413 /* Figure out what exactly is being specialized at this point.
2414 Note that for an explicit instantiation, even one for a
2415 member function, we cannot tell apriori whether the
2416 instantiation is for a member template, or just a member
2417 function of a template class. Even if a member template is
2418 being instantiated, the member template arguments may be
2419 elided if they can be deduced from the rest of the
2421 tmpl = determine_specialization (declarator, decl,
2423 member_specialization,
2427 if (!tmpl || tmpl == error_mark_node)
2428 /* We couldn't figure out what this declaration was
2430 return error_mark_node;
2433 tree gen_tmpl = most_general_template (tmpl);
2435 if (explicit_instantiation)
2437 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2438 is done by do_decl_instantiation later. */
2440 int arg_depth = TMPL_ARGS_DEPTH (targs);
2441 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2443 if (arg_depth > parm_depth)
2445 /* If TMPL is not the most general template (for
2446 example, if TMPL is a friend template that is
2447 injected into namespace scope), then there will
2448 be too many levels of TARGS. Remove some of them
2453 new_targs = make_tree_vec (parm_depth);
2454 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2455 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2456 = TREE_VEC_ELT (targs, i);
2460 return instantiate_template (tmpl, targs, tf_error);
2463 /* If we thought that the DECL was a member function, but it
2464 turns out to be specializing a static member function,
2465 make DECL a static member function as well. */
2466 if (DECL_STATIC_FUNCTION_P (tmpl)
2467 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2468 revert_static_member_fn (decl);
2470 /* If this is a specialization of a member template of a
2471 template class, we want to return the TEMPLATE_DECL, not
2472 the specialization of it. */
2473 if (tsk == tsk_template)
2475 tree result = DECL_TEMPLATE_RESULT (tmpl);
2476 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2477 DECL_INITIAL (result) = NULL_TREE;
2481 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2482 DECL_SOURCE_LOCATION (result)
2483 = DECL_SOURCE_LOCATION (decl);
2484 /* We want to use the argument list specified in the
2485 definition, not in the original declaration. */
2486 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2487 for (parm = DECL_ARGUMENTS (result); parm;
2488 parm = TREE_CHAIN (parm))
2489 DECL_CONTEXT (parm) = result;
2491 return register_specialization (tmpl, gen_tmpl, targs,
2495 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2496 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2498 /* Inherit default function arguments from the template
2499 DECL is specializing. */
2500 copy_default_args_to_explicit_spec (decl);
2502 /* This specialization has the same protection as the
2503 template it specializes. */
2504 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2505 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2507 /* 7.1.1-1 [dcl.stc]
2509 A storage-class-specifier shall not be specified in an
2510 explicit specialization...
2512 The parser rejects these, so unless action is taken here,
2513 explicit function specializations will always appear with
2516 The action recommended by the C++ CWG in response to C++
2517 defect report 605 is to make the storage class and linkage
2518 of the explicit specialization match the templated function:
2520 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2522 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2524 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2525 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2527 /* This specialization has the same linkage and visibility as
2528 the function template it specializes. */
2529 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2530 if (! TREE_PUBLIC (decl))
2532 DECL_INTERFACE_KNOWN (decl) = 1;
2533 DECL_NOT_REALLY_EXTERN (decl) = 1;
2535 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2536 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2538 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2539 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2543 /* If DECL is a friend declaration, declared using an
2544 unqualified name, the namespace associated with DECL may
2545 have been set incorrectly. For example, in:
2547 template <typename T> void f(T);
2549 struct S { friend void f<int>(int); }
2552 we will have set the DECL_CONTEXT for the friend
2553 declaration to N, rather than to the global namespace. */
2554 if (DECL_NAMESPACE_SCOPE_P (decl))
2555 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2557 if (is_friend && !have_def)
2558 /* This is not really a declaration of a specialization.
2559 It's just the name of an instantiation. But, it's not
2560 a request for an instantiation, either. */
2561 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2562 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2563 /* This is indeed a specialization. In case of constructors
2564 and destructors, we need in-charge and not-in-charge
2565 versions in V3 ABI. */
2566 clone_function_decl (decl, /*update_method_vec_p=*/0);
2568 /* Register this specialization so that we can find it
2570 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2577 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2578 parameters. These are represented in the same format used for
2579 DECL_TEMPLATE_PARMS. */
2582 comp_template_parms (const_tree parms1, const_tree parms2)
2587 if (parms1 == parms2)
2590 for (p1 = parms1, p2 = parms2;
2591 p1 != NULL_TREE && p2 != NULL_TREE;
2592 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2594 tree t1 = TREE_VALUE (p1);
2595 tree t2 = TREE_VALUE (p2);
2598 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2599 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2601 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2604 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2606 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2607 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2609 /* If either of the template parameters are invalid, assume
2610 they match for the sake of error recovery. */
2611 if (parm1 == error_mark_node || parm2 == error_mark_node)
2614 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2617 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2618 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2619 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2621 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2626 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2627 /* One set of parameters has more parameters lists than the
2634 /* Determine whether PARM is a parameter pack. */
2637 template_parameter_pack_p (const_tree parm)
2639 /* Determine if we have a non-type template parameter pack. */
2640 if (TREE_CODE (parm) == PARM_DECL)
2641 return (DECL_TEMPLATE_PARM_P (parm)
2642 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2644 /* If this is a list of template parameters, we could get a
2645 TYPE_DECL or a TEMPLATE_DECL. */
2646 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2647 parm = TREE_TYPE (parm);
2649 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2650 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2651 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2654 /* Determine if T is a function parameter pack. */
2657 function_parameter_pack_p (const_tree t)
2659 if (t && TREE_CODE (t) == PARM_DECL)
2660 return FUNCTION_PARAMETER_PACK_P (t);
2664 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2665 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2668 get_function_template_decl (const_tree primary_func_tmpl_inst)
2670 if (! primary_func_tmpl_inst
2671 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2672 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2675 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2678 /* Return true iff the function parameter PARAM_DECL was expanded
2679 from the function parameter pack PACK. */
2682 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2684 if (DECL_ARTIFICIAL (param_decl)
2685 || !function_parameter_pack_p (pack))
2688 gcc_assert (DECL_NAME (param_decl) && DECL_NAME (pack));
2690 /* The parameter pack and its pack arguments have the same
2692 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2695 /* Determine whether ARGS describes a variadic template args list,
2696 i.e., one that is terminated by a template argument pack. */
2699 template_args_variadic_p (tree args)
2704 if (args == NULL_TREE)
2707 args = INNERMOST_TEMPLATE_ARGS (args);
2708 nargs = TREE_VEC_LENGTH (args);
2713 last_parm = TREE_VEC_ELT (args, nargs - 1);
2715 return ARGUMENT_PACK_P (last_parm);
2718 /* Generate a new name for the parameter pack name NAME (an
2719 IDENTIFIER_NODE) that incorporates its */
2722 make_ith_pack_parameter_name (tree name, int i)
2724 /* Munge the name to include the parameter index. */
2725 #define NUMBUF_LEN 128
2726 char numbuf[NUMBUF_LEN];
2730 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2731 newname_len = IDENTIFIER_LENGTH (name)
2732 + strlen (numbuf) + 2;
2733 newname = (char*)alloca (newname_len);
2734 snprintf (newname, newname_len,
2735 "%s#%i", IDENTIFIER_POINTER (name), i);
2736 return get_identifier (newname);
2739 /* Return true if T is a primary function
2740 or class template instantiation. */
2743 primary_template_instantiation_p (const_tree t)
2748 if (TREE_CODE (t) == FUNCTION_DECL)
2749 return DECL_LANG_SPECIFIC (t)
2750 && DECL_TEMPLATE_INSTANTIATION (t)
2751 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2752 else if (CLASS_TYPE_P (t))
2753 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2754 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2758 /* Return true if PARM is a template template parameter. */
2761 template_template_parameter_p (const_tree parm)
2763 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2766 /* Return the template parameters of T if T is a
2767 primary template instantiation, NULL otherwise. */
2770 get_primary_template_innermost_parameters (const_tree t)
2772 tree parms = NULL, template_info = NULL;
2774 if ((template_info = get_template_info (t))
2775 && primary_template_instantiation_p (t))
2776 parms = INNERMOST_TEMPLATE_PARMS
2777 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2782 /* Returns the template arguments of T if T is a template instantiation,
2786 get_template_innermost_arguments (const_tree t)
2788 tree args = NULL, template_info = NULL;
2790 if ((template_info = get_template_info (t))
2791 && TI_ARGS (template_info))
2792 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
2797 /* Return the argument pack elements of T if T is a template argument pack,
2801 get_template_argument_pack_elems (const_tree t)
2803 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
2804 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
2807 return ARGUMENT_PACK_ARGS (t);
2810 /* Structure used to track the progress of find_parameter_packs_r. */
2811 struct find_parameter_pack_data
2813 /* TREE_LIST that will contain all of the parameter packs found by
2815 tree* parameter_packs;
2817 /* Set of AST nodes that have been visited by the traversal. */
2818 struct pointer_set_t *visited;
2821 /* Identifies all of the argument packs that occur in a template
2822 argument and appends them to the TREE_LIST inside DATA, which is a
2823 find_parameter_pack_data structure. This is a subroutine of
2824 make_pack_expansion and uses_parameter_packs. */
2826 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2829 struct find_parameter_pack_data* ppd =
2830 (struct find_parameter_pack_data*)data;
2831 bool parameter_pack_p = false;
2833 /* Identify whether this is a parameter pack or not. */
2834 switch (TREE_CODE (t))
2836 case TEMPLATE_PARM_INDEX:
2837 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2838 parameter_pack_p = true;
2841 case TEMPLATE_TYPE_PARM:
2842 case TEMPLATE_TEMPLATE_PARM:
2843 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2844 parameter_pack_p = true;
2848 if (FUNCTION_PARAMETER_PACK_P (t))
2850 /* We don't want to walk into the type of a PARM_DECL,
2851 because we don't want to see the type parameter pack. */
2853 parameter_pack_p = true;
2858 /* Not a parameter pack. */
2862 if (parameter_pack_p)
2864 /* Add this parameter pack to the list. */
2865 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2869 cp_walk_tree (&TYPE_CONTEXT (t),
2870 &find_parameter_packs_r, ppd, ppd->visited);
2872 /* This switch statement will return immediately if we don't find a
2874 switch (TREE_CODE (t))
2876 case TEMPLATE_PARM_INDEX:
2879 case BOUND_TEMPLATE_TEMPLATE_PARM:
2880 /* Check the template itself. */
2881 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2882 &find_parameter_packs_r, ppd, ppd->visited);
2883 /* Check the template arguments. */
2884 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2889 case TEMPLATE_TYPE_PARM:
2890 case TEMPLATE_TEMPLATE_PARM:
2897 if (TYPE_PTRMEMFUNC_P (t))
2903 if (TYPE_TEMPLATE_INFO (t))
2904 cp_walk_tree (&TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
2905 &find_parameter_packs_r, ppd, ppd->visited);
2911 cp_walk_tree (&TREE_TYPE (t),
2912 &find_parameter_packs_r, ppd, ppd->visited);
2916 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
2921 case TYPE_PACK_EXPANSION:
2922 case EXPR_PACK_EXPANSION:
2927 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
2932 case IDENTIFIER_NODE:
2933 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
2945 /* Determines if the expression or type T uses any parameter packs. */
2947 uses_parameter_packs (tree t)
2949 tree parameter_packs = NULL_TREE;
2950 struct find_parameter_pack_data ppd;
2951 ppd.parameter_packs = ¶meter_packs;
2952 ppd.visited = pointer_set_create ();
2953 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2954 pointer_set_destroy (ppd.visited);
2955 return parameter_packs != NULL_TREE;
2958 /* Turn ARG, which may be an expression, type, or a TREE_LIST
2959 representation a base-class initializer into a parameter pack
2960 expansion. If all goes well, the resulting node will be an
2961 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
2964 make_pack_expansion (tree arg)
2967 tree parameter_packs = NULL_TREE;
2968 bool for_types = false;
2969 struct find_parameter_pack_data ppd;
2971 if (!arg || arg == error_mark_node)
2974 if (TREE_CODE (arg) == TREE_LIST)
2976 /* The only time we will see a TREE_LIST here is for a base
2977 class initializer. In this case, the TREE_PURPOSE will be a
2978 _TYPE node (representing the base class expansion we're
2979 initializing) and the TREE_VALUE will be a TREE_LIST
2980 containing the initialization arguments.
2982 The resulting expansion looks somewhat different from most
2983 expansions. Rather than returning just one _EXPANSION, we
2984 return a TREE_LIST whose TREE_PURPOSE is a
2985 TYPE_PACK_EXPANSION containing the bases that will be
2986 initialized. The TREE_VALUE will be identical to the
2987 original TREE_VALUE, which is a list of arguments that will
2988 be passed to each base. We do not introduce any new pack
2989 expansion nodes into the TREE_VALUE (although it is possible
2990 that some already exist), because the TREE_PURPOSE and
2991 TREE_VALUE all need to be expanded together with the same
2992 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
2993 resulting TREE_PURPOSE will mention the parameter packs in
2994 both the bases and the arguments to the bases. */
2997 tree parameter_packs = NULL_TREE;
2999 /* Determine which parameter packs will be used by the base
3001 ppd.visited = pointer_set_create ();
3002 ppd.parameter_packs = ¶meter_packs;
3003 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3006 if (parameter_packs == NULL_TREE)
3008 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3009 pointer_set_destroy (ppd.visited);
3010 return error_mark_node;
3013 if (TREE_VALUE (arg) != void_type_node)
3015 /* Collect the sets of parameter packs used in each of the
3016 initialization arguments. */
3017 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3019 /* Determine which parameter packs will be expanded in this
3021 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3026 pointer_set_destroy (ppd.visited);
3028 /* Create the pack expansion type for the base type. */
3029 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3030 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3031 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3033 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3034 they will rarely be compared to anything. */
3035 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3037 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3040 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3043 /* Build the PACK_EXPANSION_* node. */
3045 ? cxx_make_type (TYPE_PACK_EXPANSION)
3046 : make_node (EXPR_PACK_EXPANSION);
3047 SET_PACK_EXPANSION_PATTERN (result, arg);
3048 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3050 /* Propagate type and const-expression information. */
3051 TREE_TYPE (result) = TREE_TYPE (arg);
3052 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3055 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3056 they will rarely be compared to anything. */
3057 SET_TYPE_STRUCTURAL_EQUALITY (result);
3059 /* Determine which parameter packs will be expanded. */
3060 ppd.parameter_packs = ¶meter_packs;
3061 ppd.visited = pointer_set_create ();
3062 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3063 pointer_set_destroy (ppd.visited);
3065 /* Make sure we found some parameter packs. */
3066 if (parameter_packs == NULL_TREE)
3069 error ("expansion pattern %<%T%> contains no argument packs", arg);
3071 error ("expansion pattern %<%E%> contains no argument packs", arg);
3072 return error_mark_node;
3074 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3079 /* Checks T for any "bare" parameter packs, which have not yet been
3080 expanded, and issues an error if any are found. This operation can
3081 only be done on full expressions or types (e.g., an expression
3082 statement, "if" condition, etc.), because we could have expressions like:
3084 foo(f(g(h(args)))...)
3086 where "args" is a parameter pack. check_for_bare_parameter_packs
3087 should not be called for the subexpressions args, h(args),
3088 g(h(args)), or f(g(h(args))), because we would produce erroneous
3091 Returns TRUE and emits an error if there were bare parameter packs,
3092 returns FALSE otherwise. */
3094 check_for_bare_parameter_packs (tree t)
3096 tree parameter_packs = NULL_TREE;
3097 struct find_parameter_pack_data ppd;
3099 if (!processing_template_decl || !t || t == error_mark_node)
3102 if (TREE_CODE (t) == TYPE_DECL)
3105 ppd.parameter_packs = ¶meter_packs;
3106 ppd.visited = pointer_set_create ();
3107 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3108 pointer_set_destroy (ppd.visited);
3110 if (parameter_packs)
3112 error ("parameter packs not expanded with %<...%>:");
3113 while (parameter_packs)
3115 tree pack = TREE_VALUE (parameter_packs);
3116 tree name = NULL_TREE;
3118 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3119 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3120 name = TYPE_NAME (pack);
3121 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3122 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3124 name = DECL_NAME (pack);
3127 inform (input_location, " %qD", name);
3129 inform (input_location, " <anonymous>");
3131 parameter_packs = TREE_CHAIN (parameter_packs);
3140 /* Expand any parameter packs that occur in the template arguments in
3143 expand_template_argument_pack (tree args)
3145 tree result_args = NULL_TREE;
3146 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3147 int num_result_args = -1;
3149 /* First, determine if we need to expand anything, and the number of
3150 slots we'll need. */
3151 for (in_arg = 0; in_arg < nargs; ++in_arg)
3153 tree arg = TREE_VEC_ELT (args, in_arg);
3154 if (ARGUMENT_PACK_P (arg))
3156 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3157 if (num_result_args < 0)
3158 num_result_args = in_arg + num_packed;
3160 num_result_args += num_packed;
3164 if (num_result_args >= 0)
3169 /* If no expansion is necessary, we're done. */
3170 if (num_result_args < 0)
3173 /* Expand arguments. */
3174 result_args = make_tree_vec (num_result_args);
3175 for (in_arg = 0; in_arg < nargs; ++in_arg)
3177 tree arg = TREE_VEC_ELT (args, in_arg);
3178 if (ARGUMENT_PACK_P (arg))
3180 tree packed = ARGUMENT_PACK_ARGS (arg);
3181 int i, num_packed = TREE_VEC_LENGTH (packed);
3182 for (i = 0; i < num_packed; ++i, ++out_arg)
3183 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3187 TREE_VEC_ELT (result_args, out_arg) = arg;
3195 /* Checks if DECL shadows a template parameter.
3197 [temp.local]: A template-parameter shall not be redeclared within its
3198 scope (including nested scopes).
3200 Emits an error and returns TRUE if the DECL shadows a parameter,
3201 returns FALSE otherwise. */
3204 check_template_shadow (tree decl)
3208 /* If we're not in a template, we can't possibly shadow a template
3210 if (!current_template_parms)
3213 /* Figure out what we're shadowing. */
3214 if (TREE_CODE (decl) == OVERLOAD)
3215 decl = OVL_CURRENT (decl);
3216 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3218 /* If there's no previous binding for this name, we're not shadowing
3219 anything, let alone a template parameter. */
3223 /* If we're not shadowing a template parameter, we're done. Note
3224 that OLDDECL might be an OVERLOAD (or perhaps even an
3225 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3227 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3230 /* We check for decl != olddecl to avoid bogus errors for using a
3231 name inside a class. We check TPFI to avoid duplicate errors for
3232 inline member templates. */
3234 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3237 error ("declaration of %q+#D", decl);
3238 error (" shadows template parm %q+#D", olddecl);
3242 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3243 ORIG_LEVEL, DECL, and TYPE. */
3246 build_template_parm_index (int index,
3252 tree t = make_node (TEMPLATE_PARM_INDEX);
3253 TEMPLATE_PARM_IDX (t) = index;
3254 TEMPLATE_PARM_LEVEL (t) = level;
3255 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3256 TEMPLATE_PARM_DECL (t) = decl;
3257 TREE_TYPE (t) = type;
3258 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3259 TREE_READONLY (t) = TREE_READONLY (decl);
3264 /* Find the canonical type parameter for the given template type
3265 parameter. Returns the canonical type parameter, which may be TYPE
3266 if no such parameter existed. */
3268 canonical_type_parameter (tree type)
3271 int idx = TEMPLATE_TYPE_IDX (type);
3272 if (!canonical_template_parms)
3273 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3275 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3276 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3278 list = VEC_index (tree, canonical_template_parms, idx);
3279 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3280 list = TREE_CHAIN (list);
3283 return TREE_VALUE (list);
3286 VEC_replace(tree, canonical_template_parms, idx,
3287 tree_cons (NULL_TREE, type,
3288 VEC_index (tree, canonical_template_parms, idx)));
3293 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3294 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3295 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3296 new one is created. */
3299 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3300 tsubst_flags_t complain)
3302 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3303 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3304 != TEMPLATE_PARM_LEVEL (index) - levels))
3306 tree orig_decl = TEMPLATE_PARM_DECL (index);
3309 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3310 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3311 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3312 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3313 DECL_ARTIFICIAL (decl) = 1;
3314 SET_DECL_TEMPLATE_PARM_P (decl);
3316 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3317 TEMPLATE_PARM_LEVEL (index) - levels,
3318 TEMPLATE_PARM_ORIG_LEVEL (index),
3320 TEMPLATE_PARM_DESCENDANTS (index) = t;
3321 TEMPLATE_PARM_PARAMETER_PACK (t)
3322 = TEMPLATE_PARM_PARAMETER_PACK (index);
3324 /* Template template parameters need this. */
3325 if (TREE_CODE (decl) == TEMPLATE_DECL)
3326 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3327 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3331 return TEMPLATE_PARM_DESCENDANTS (index);
3334 /* Process information from new template parameter PARM and append it to the
3335 LIST being built. This new parameter is a non-type parameter iff
3336 IS_NON_TYPE is true. This new parameter is a parameter
3337 pack iff IS_PARAMETER_PACK is true. The location of PARM is in
3341 process_template_parm (tree list, location_t parm_loc, tree parm, bool is_non_type,
3342 bool is_parameter_pack)
3349 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3350 defval = TREE_PURPOSE (parm);
3354 tree p = tree_last (list);
3356 if (p && TREE_VALUE (p) != error_mark_node)
3359 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3360 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3362 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3372 parm = TREE_VALUE (parm);
3374 SET_DECL_TEMPLATE_PARM_P (parm);
3376 if (TREE_TYPE (parm) == error_mark_node)
3378 err_parm_list = build_tree_list (defval, parm);
3379 TREE_VALUE (err_parm_list) = error_mark_node;
3380 return chainon (list, err_parm_list);
3386 The top-level cv-qualifiers on the template-parameter are
3387 ignored when determining its type. */
3388 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3389 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3391 err_parm_list = build_tree_list (defval, parm);
3392 TREE_VALUE (err_parm_list) = error_mark_node;
3393 return chainon (list, err_parm_list);
3396 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3398 /* This template parameter is not a parameter pack, but it
3399 should be. Complain about "bare" parameter packs. */
3400 check_for_bare_parameter_packs (TREE_TYPE (parm));
3402 /* Recover by calling this a parameter pack. */
3403 is_parameter_pack = true;
3407 /* A template parameter is not modifiable. */
3408 TREE_CONSTANT (parm) = 1;
3409 TREE_READONLY (parm) = 1;
3410 decl = build_decl (parm_loc,
3411 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3412 TREE_CONSTANT (decl) = 1;
3413 TREE_READONLY (decl) = 1;
3414 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3415 = build_template_parm_index (idx, processing_template_decl,
3416 processing_template_decl,
3417 decl, TREE_TYPE (parm));
3419 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3420 = is_parameter_pack;
3425 parm = TREE_VALUE (TREE_VALUE (parm));
3427 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3429 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3430 /* This is for distinguishing between real templates and template
3431 template parameters */
3432 TREE_TYPE (parm) = t;
3433 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3438 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3439 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3440 decl = build_decl (parm_loc,
3441 TYPE_DECL, parm, t);
3444 TYPE_NAME (t) = decl;
3445 TYPE_STUB_DECL (t) = decl;
3447 TEMPLATE_TYPE_PARM_INDEX (t)
3448 = build_template_parm_index (idx, processing_template_decl,
3449 processing_template_decl,
3450 decl, TREE_TYPE (parm));
3451 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3452 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3454 DECL_ARTIFICIAL (decl) = 1;
3455 SET_DECL_TEMPLATE_PARM_P (decl);
3457 parm = build_tree_list (defval, parm);
3458 return chainon (list, parm);
3461 /* The end of a template parameter list has been reached. Process the
3462 tree list into a parameter vector, converting each parameter into a more
3463 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3467 end_template_parm_list (tree parms)
3471 tree saved_parmlist = make_tree_vec (list_length (parms));
3473 current_template_parms
3474 = tree_cons (size_int (processing_template_decl),
3475 saved_parmlist, current_template_parms);
3477 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3479 next = TREE_CHAIN (parm);
3480 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3481 TREE_CHAIN (parm) = NULL_TREE;
3484 --processing_template_parmlist;
3486 return saved_parmlist;
3489 /* end_template_decl is called after a template declaration is seen. */
3492 end_template_decl (void)
3494 reset_specialization ();
3496 if (! processing_template_decl)
3499 /* This matches the pushlevel in begin_template_parm_list. */
3502 --processing_template_decl;
3503 current_template_parms = TREE_CHAIN (current_template_parms);
3506 /* Within the declaration of a template, return all levels of template
3507 parameters that apply. The template parameters are represented as
3508 a TREE_VEC, in the form documented in cp-tree.h for template
3512 current_template_args (void)
3515 tree args = NULL_TREE;
3516 int length = TMPL_PARMS_DEPTH (current_template_parms);
3519 /* If there is only one level of template parameters, we do not
3520 create a TREE_VEC of TREE_VECs. Instead, we return a single
3521 TREE_VEC containing the arguments. */
3523 args = make_tree_vec (length);
3525 for (header = current_template_parms; header; header = TREE_CHAIN (header))
3527 tree a = copy_node (TREE_VALUE (header));
3530 TREE_TYPE (a) = NULL_TREE;
3531 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3533 tree t = TREE_VEC_ELT (a, i);
3535 /* T will be a list if we are called from within a
3536 begin/end_template_parm_list pair, but a vector directly
3537 if within a begin/end_member_template_processing pair. */
3538 if (TREE_CODE (t) == TREE_LIST)
3542 if (!error_operand_p (t))
3544 if (TREE_CODE (t) == TYPE_DECL
3545 || TREE_CODE (t) == TEMPLATE_DECL)
3549 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3551 /* Turn this argument into a TYPE_ARGUMENT_PACK
3552 with a single element, which expands T. */
3553 tree vec = make_tree_vec (1);
3554 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3556 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3557 SET_ARGUMENT_PACK_ARGS (t, vec);
3562 t = DECL_INITIAL (t);
3564 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3566 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3567 with a single element, which expands T. */
3568 tree vec = make_tree_vec (1);
3569 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3570 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3572 t = make_node (NONTYPE_ARGUMENT_PACK);
3573 SET_ARGUMENT_PACK_ARGS (t, vec);
3574 TREE_TYPE (t) = type;
3577 TREE_VEC_ELT (a, i) = t;
3583 TREE_VEC_ELT (args, --l) = a;
3591 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3592 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3593 a member template. Used by push_template_decl below. */
3596 build_template_decl (tree decl, tree parms, bool member_template_p)
3598 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3599 DECL_TEMPLATE_PARMS (tmpl) = parms;
3600 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3601 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3606 struct template_parm_data
3608 /* The level of the template parameters we are currently
3612 /* The index of the specialization argument we are currently
3616 /* An array whose size is the number of template parameters. The
3617 elements are nonzero if the parameter has been used in any one
3618 of the arguments processed so far. */
3621 /* An array whose size is the number of template arguments. The
3622 elements are nonzero if the argument makes use of template
3623 parameters of this level. */
3624 int* arg_uses_template_parms;
3627 /* Subroutine of push_template_decl used to see if each template
3628 parameter in a partial specialization is used in the explicit
3629 argument list. If T is of the LEVEL given in DATA (which is
3630 treated as a template_parm_data*), then DATA->PARMS is marked
3634 mark_template_parm (tree t, void* data)
3638 struct template_parm_data* tpd = (struct template_parm_data*) data;
3640 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3642 level = TEMPLATE_PARM_LEVEL (t);
3643 idx = TEMPLATE_PARM_IDX (t);
3647 level = TEMPLATE_TYPE_LEVEL (t);
3648 idx = TEMPLATE_TYPE_IDX (t);
3651 if (level == tpd->level)
3653 tpd->parms[idx] = 1;
3654 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
3657 /* Return zero so that for_each_template_parm will continue the
3658 traversal of the tree; we want to mark *every* template parm. */
3662 /* Process the partial specialization DECL. */
3665 process_partial_specialization (tree decl)
3667 tree type = TREE_TYPE (decl);
3668 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
3669 tree specargs = CLASSTYPE_TI_ARGS (type);
3670 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
3671 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
3673 int nargs = TREE_VEC_LENGTH (inner_args);
3676 int did_error_intro = 0;
3677 struct template_parm_data tpd;
3678 struct template_parm_data tpd2;
3680 gcc_assert (current_template_parms);
3682 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3683 ntparms = TREE_VEC_LENGTH (inner_parms);
3685 /* We check that each of the template parameters given in the
3686 partial specialization is used in the argument list to the
3687 specialization. For example:
3689 template <class T> struct S;
3690 template <class T> struct S<T*>;
3692 The second declaration is OK because `T*' uses the template
3693 parameter T, whereas
3695 template <class T> struct S<int>;
3697 is no good. Even trickier is:
3708 The S2<T> declaration is actually invalid; it is a
3709 full-specialization. Of course,
3712 struct S2<T (*)(U)>;
3714 or some such would have been OK. */
3715 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
3716 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
3717 memset (tpd.parms, 0, sizeof (int) * ntparms);
3719 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
3720 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
3721 for (i = 0; i < nargs; ++i)
3723 tpd.current_arg = i;
3724 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
3725 &mark_template_parm,
3728 /*include_nondeduced_p=*/false);
3730 for (i = 0; i < ntparms; ++i)
3731 if (tpd.parms[i] == 0)
3733 /* One of the template parms was not used in the
3735 if (!did_error_intro)
3737 error ("template parameters not used in partial specialization:");
3738 did_error_intro = 1;
3741 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
3744 /* [temp.class.spec]
3746 The argument list of the specialization shall not be identical to
3747 the implicit argument list of the primary template. */
3748 if (comp_template_args
3750 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
3752 error ("partial specialization %qT does not specialize any template arguments", type);
3754 /* [temp.class.spec]
3756 A partially specialized non-type argument expression shall not
3757 involve template parameters of the partial specialization except
3758 when the argument expression is a simple identifier.
3760 The type of a template parameter corresponding to a specialized
3761 non-type argument shall not be dependent on a parameter of the
3764 Also, we verify that pack expansions only occur at the
3765 end of the argument list. */
3766 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
3768 for (i = 0; i < nargs; ++i)
3770 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
3771 tree arg = TREE_VEC_ELT (inner_args, i);
3772 tree packed_args = NULL_TREE;
3775 if (ARGUMENT_PACK_P (arg))
3777 /* Extract the arguments from the argument pack. We'll be
3778 iterating over these in the following loop. */
3779 packed_args = ARGUMENT_PACK_ARGS (arg);
3780 len = TREE_VEC_LENGTH (packed_args);
3783 for (j = 0; j < len; j++)
3786 /* Get the Jth argument in the parameter pack. */
3787 arg = TREE_VEC_ELT (packed_args, j);
3789 if (PACK_EXPANSION_P (arg))
3791 /* Pack expansions must come at the end of the
3793 if ((packed_args && j < len - 1)
3794 || (!packed_args && i < nargs - 1))
3796 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3797 error ("parameter pack argument %qE must be at the end of the template argument list", arg);
3799 error ("parameter pack argument %qT must be at the end of the template argument list", arg);
3802 TREE_VEC_ELT (packed_args, j) = error_mark_node;
3806 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3807 /* We only care about the pattern. */
3808 arg = PACK_EXPANSION_PATTERN (arg);
3810 if (/* These first two lines are the `non-type' bit. */
3812 && TREE_CODE (arg) != TEMPLATE_DECL
3813 /* This next line is the `argument expression is not just a
3814 simple identifier' condition and also the `specialized
3815 non-type argument' bit. */
3816 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
3818 if ((!packed_args && tpd.arg_uses_template_parms[i])
3819 || (packed_args && uses_template_parms (arg)))
3820 error ("template argument %qE involves template parameter(s)",
3824 /* Look at the corresponding template parameter,
3825 marking which template parameters its type depends
3827 tree type = TREE_TYPE (parm);
3831 /* We haven't yet initialized TPD2. Do so now. */
3832 tpd2.arg_uses_template_parms
3833 = (int *) alloca (sizeof (int) * nargs);
3834 /* The number of parameters here is the number in the
3835 main template, which, as checked in the assertion
3837 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
3839 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
3842 /* Mark the template parameters. But this time, we're
3843 looking for the template parameters of the main
3844 template, not in the specialization. */
3845 tpd2.current_arg = i;
3846 tpd2.arg_uses_template_parms[i] = 0;
3847 memset (tpd2.parms, 0, sizeof (int) * nargs);
3848 for_each_template_parm (type,
3849 &mark_template_parm,
3852 /*include_nondeduced_p=*/false);
3854 if (tpd2.arg_uses_template_parms [i])
3856 /* The type depended on some template parameters.
3857 If they are fully specialized in the
3858 specialization, that's OK. */
3860 for (j = 0; j < nargs; ++j)
3861 if (tpd2.parms[j] != 0
3862 && tpd.arg_uses_template_parms [j])
3864 error ("type %qT of template argument %qE depends "
3865 "on template parameter(s)",
3876 /* We should only get here once. */
3877 gcc_assert (!COMPLETE_TYPE_P (type));
3879 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
3880 = tree_cons (specargs, inner_parms,
3881 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
3882 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
3886 /* Check that a template declaration's use of default arguments and
3887 parameter packs is not invalid. Here, PARMS are the template
3888 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
3889 a primary template. IS_PARTIAL is nonzero if DECL is a partial
3893 IS_FRIEND_DECL is nonzero if DECL is a friend function template
3894 declaration (but not a definition); 1 indicates a declaration, 2
3895 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
3896 emitted for extraneous default arguments.
3898 Returns TRUE if there were no errors found, FALSE otherwise. */
3901 check_default_tmpl_args (tree decl, tree parms, int is_primary,
3902 int is_partial, int is_friend_decl)
3905 int last_level_to_check;
3907 bool no_errors = true;
3911 A default template-argument shall not be specified in a
3912 function template declaration or a function template definition, nor
3913 in the template-parameter-list of the definition of a member of a
3916 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
3917 /* You can't have a function template declaration in a local
3918 scope, nor you can you define a member of a class template in a
3922 if (current_class_type
3923 && !TYPE_BEING_DEFINED (current_class_type)
3924 && DECL_LANG_SPECIFIC (decl)
3925 && DECL_DECLARES_FUNCTION_P (decl)
3926 /* If this is either a friend defined in the scope of the class
3927 or a member function. */
3928 && (DECL_FUNCTION_MEMBER_P (decl)
3929 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
3930 : DECL_FRIEND_CONTEXT (decl)
3931 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
3933 /* And, if it was a member function, it really was defined in
3934 the scope of the class. */
3935 && (!DECL_FUNCTION_MEMBER_P (decl)
3936 || DECL_INITIALIZED_IN_CLASS_P (decl)))
3937 /* We already checked these parameters when the template was
3938 declared, so there's no need to do it again now. This function
3939 was defined in class scope, but we're processing it's body now
3940 that the class is complete. */
3943 /* Core issue 226 (C++0x only): the following only applies to class
3945 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
3949 If a template-parameter has a default template-argument, all
3950 subsequent template-parameters shall have a default
3951 template-argument supplied. */
3952 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
3954 tree inner_parms = TREE_VALUE (parm_level);
3955 int ntparms = TREE_VEC_LENGTH (inner_parms);
3956 int seen_def_arg_p = 0;
3959 for (i = 0; i < ntparms; ++i)
3961 tree parm = TREE_VEC_ELT (inner_parms, i);
3963 if (parm == error_mark_node)
3966 if (TREE_PURPOSE (parm))
3968 else if (seen_def_arg_p
3969 && !template_parameter_pack_p (TREE_VALUE (parm)))
3971 error ("no default argument for %qD", TREE_VALUE (parm));
3972 /* For better subsequent error-recovery, we indicate that
3973 there should have been a default argument. */
3974 TREE_PURPOSE (parm) = error_mark_node;
3980 /* Don't complain about an enclosing partial
3982 && parm_level == parms
3983 && TREE_CODE (decl) == TYPE_DECL
3985 && template_parameter_pack_p (TREE_VALUE (parm)))
3987 /* A primary class template can only have one
3988 parameter pack, at the end of the template
3991 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
3992 error ("parameter pack %qE must be at the end of the"
3993 " template parameter list", TREE_VALUE (parm));
3995 error ("parameter pack %qT must be at the end of the"
3996 " template parameter list",
3997 TREE_TYPE (TREE_VALUE (parm)));
3999 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4007 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4011 /* For an ordinary class template, default template arguments are
4012 allowed at the innermost level, e.g.:
4013 template <class T = int>
4015 but, in a partial specialization, they're not allowed even
4016 there, as we have in [temp.class.spec]:
4018 The template parameter list of a specialization shall not
4019 contain default template argument values.
4021 So, for a partial specialization, or for a function template
4022 (in C++98/C++03), we look at all of them. */
4025 /* But, for a primary class template that is not a partial
4026 specialization we look at all template parameters except the
4028 parms = TREE_CHAIN (parms);
4030 /* Figure out what error message to issue. */
4031 if (is_friend_decl == 2)
4032 msg = "default template arguments may not be used in function template friend re-declaration";
4033 else if (is_friend_decl)
4034 msg = "default template arguments may not be used in function template friend declarations";
4035 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4036 msg = ("default template arguments may not be used in function templates "
4037 "without -std=c++0x or -std=gnu++0x");
4038 else if (is_partial)
4039 msg = "default template arguments may not be used in partial specializations";
4041 msg = "default argument for template parameter for class enclosing %qD";
4043 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4044 /* If we're inside a class definition, there's no need to
4045 examine the parameters to the class itself. On the one
4046 hand, they will be checked when the class is defined, and,
4047 on the other, default arguments are valid in things like:
4048 template <class T = double>
4049 struct S { template <class U> void f(U); };
4050 Here the default argument for `S' has no bearing on the
4051 declaration of `f'. */
4052 last_level_to_check = template_class_depth (current_class_type) + 1;
4054 /* Check everything. */
4055 last_level_to_check = 0;
4057 for (parm_level = parms;
4058 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4059 parm_level = TREE_CHAIN (parm_level))
4061 tree inner_parms = TREE_VALUE (parm_level);
4065 ntparms = TREE_VEC_LENGTH (inner_parms);
4066 for (i = 0; i < ntparms; ++i)
4068 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4071 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4076 if (is_friend_decl == 2)
4083 /* Clear out the default argument so that we are not
4085 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4089 /* At this point, if we're still interested in issuing messages,
4090 they must apply to classes surrounding the object declared. */
4092 msg = "default argument for template parameter for class enclosing %qD";
4098 /* Worker for push_template_decl_real, called via
4099 for_each_template_parm. DATA is really an int, indicating the
4100 level of the parameters we are interested in. If T is a template
4101 parameter of that level, return nonzero. */
4104 template_parm_this_level_p (tree t, void* data)
4106 int this_level = *(int *)data;
4109 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4110 level = TEMPLATE_PARM_LEVEL (t);
4112 level = TEMPLATE_TYPE_LEVEL (t);
4113 return level == this_level;
4116 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4117 parameters given by current_template_args, or reuses a
4118 previously existing one, if appropriate. Returns the DECL, or an
4119 equivalent one, if it is replaced via a call to duplicate_decls.
4121 If IS_FRIEND is true, DECL is a friend declaration. */
4124 push_template_decl_real (tree decl, bool is_friend)
4132 int new_template_p = 0;
4133 /* True if the template is a member template, in the sense of
4135 bool member_template_p = false;
4137 if (decl == error_mark_node || !current_template_parms)
4138 return error_mark_node;
4140 /* See if this is a partial specialization. */
4141 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4142 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4143 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4145 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4149 /* For a friend, we want the context of the friend function, not
4150 the type of which it is a friend. */
4151 ctx = DECL_CONTEXT (decl);
4152 else if (CP_DECL_CONTEXT (decl)
4153 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4154 /* In the case of a virtual function, we want the class in which
4156 ctx = CP_DECL_CONTEXT (decl);
4158 /* Otherwise, if we're currently defining some class, the DECL
4159 is assumed to be a member of the class. */
4160 ctx = current_scope ();
4162 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4165 if (!DECL_CONTEXT (decl))
4166 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4168 /* See if this is a primary template. */
4169 if (is_friend && ctx)
4170 /* A friend template that specifies a class context, i.e.
4171 template <typename T> friend void A<T>::f();
4175 primary = template_parm_scope_p ();
4179 if (DECL_CLASS_SCOPE_P (decl))
4180 member_template_p = true;
4181 if (TREE_CODE (decl) == TYPE_DECL
4182 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4184 error ("template class without a name");
4185 return error_mark_node;
4187 else if (TREE_CODE (decl) == FUNCTION_DECL)
4189 if (DECL_DESTRUCTOR_P (decl))
4193 A destructor shall not be a member template. */
4194 error ("destructor %qD declared as member template", decl);
4195 return error_mark_node;
4197 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4198 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
4199 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4200 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4201 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4202 == void_list_node)))
4204 /* [basic.stc.dynamic.allocation]
4206 An allocation function can be a function
4207 template. ... Template allocation functions shall
4208 have two or more parameters. */
4209 error ("invalid template declaration of %qD", decl);
4210 return error_mark_node;
4213 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4214 && CLASS_TYPE_P (TREE_TYPE (decl)))
4218 error ("template declaration of %q#D", decl);
4219 return error_mark_node;
4223 /* Check to see that the rules regarding the use of default
4224 arguments are not being violated. */
4225 check_default_tmpl_args (decl, current_template_parms,
4226 primary, is_partial, /*is_friend_decl=*/0);
4228 /* Ensure that there are no parameter packs in the type of this
4229 declaration that have not been expanded. */
4230 if (TREE_CODE (decl) == FUNCTION_DECL)
4232 /* Check each of the arguments individually to see if there are
4233 any bare parameter packs. */
4234 tree type = TREE_TYPE (decl);
4235 tree arg = DECL_ARGUMENTS (decl);
4236 tree argtype = TYPE_ARG_TYPES (type);
4238 while (arg && argtype)
4240 if (!FUNCTION_PARAMETER_PACK_P (arg)
4241 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4243 /* This is a PARM_DECL that contains unexpanded parameter
4244 packs. We have already complained about this in the
4245 check_for_bare_parameter_packs call, so just replace
4246 these types with ERROR_MARK_NODE. */
4247 TREE_TYPE (arg) = error_mark_node;
4248 TREE_VALUE (argtype) = error_mark_node;
4251 arg = TREE_CHAIN (arg);
4252 argtype = TREE_CHAIN (argtype);
4255 /* Check for bare parameter packs in the return type and the
4256 exception specifiers. */
4257 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4258 /* Errors were already issued, set return type to int
4259 as the frontend doesn't expect error_mark_node as
4261 TREE_TYPE (type) = integer_type_node;
4262 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4263 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4265 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4267 TREE_TYPE (decl) = error_mark_node;
4268 return error_mark_node;
4272 return process_partial_specialization (decl);
4274 args = current_template_args ();
4277 || TREE_CODE (ctx) == FUNCTION_DECL
4278 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4279 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4281 if (DECL_LANG_SPECIFIC (decl)
4282 && DECL_TEMPLATE_INFO (decl)
4283 && DECL_TI_TEMPLATE (decl))
4284 tmpl = DECL_TI_TEMPLATE (decl);
4285 /* If DECL is a TYPE_DECL for a class-template, then there won't
4286 be DECL_LANG_SPECIFIC. The information equivalent to
4287 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4288 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4289 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4290 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4292 /* Since a template declaration already existed for this
4293 class-type, we must be redeclaring it here. Make sure
4294 that the redeclaration is valid. */
4295 redeclare_class_template (TREE_TYPE (decl),
4296 current_template_parms);
4297 /* We don't need to create a new TEMPLATE_DECL; just use the
4298 one we already had. */
4299 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4303 tmpl = build_template_decl (decl, current_template_parms,
4307 if (DECL_LANG_SPECIFIC (decl)
4308 && DECL_TEMPLATE_SPECIALIZATION (decl))
4310 /* A specialization of a member template of a template
4312 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4313 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4314 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4320 tree a, t, current, parms;
4322 tree tinfo = get_template_info (decl);
4326 error ("template definition of non-template %q#D", decl);
4327 return error_mark_node;
4330 tmpl = TI_TEMPLATE (tinfo);
4332 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4333 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4334 && DECL_TEMPLATE_SPECIALIZATION (decl)
4335 && DECL_MEMBER_TEMPLATE_P (tmpl))
4339 /* The declaration is a specialization of a member
4340 template, declared outside the class. Therefore, the
4341 innermost template arguments will be NULL, so we
4342 replace them with the arguments determined by the
4343 earlier call to check_explicit_specialization. */
4344 args = DECL_TI_ARGS (decl);
4347 = build_template_decl (decl, current_template_parms,
4349 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4350 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4351 DECL_TI_TEMPLATE (decl) = new_tmpl;
4352 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4353 DECL_TEMPLATE_INFO (new_tmpl)
4354 = tree_cons (tmpl, args, NULL_TREE);
4356 register_specialization (new_tmpl,
4357 most_general_template (tmpl),
4363 /* Make sure the template headers we got make sense. */
4365 parms = DECL_TEMPLATE_PARMS (tmpl);
4366 i = TMPL_PARMS_DEPTH (parms);
4367 if (TMPL_ARGS_DEPTH (args) != i)
4369 error ("expected %d levels of template parms for %q#D, got %d",
4370 i, decl, TMPL_ARGS_DEPTH (args));
4373 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4375 a = TMPL_ARGS_LEVEL (args, i);
4376 t = INNERMOST_TEMPLATE_PARMS (parms);
4378 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4380 if (current == decl)
4381 error ("got %d template parameters for %q#D",
4382 TREE_VEC_LENGTH (a), decl);
4384 error ("got %d template parameters for %q#T",
4385 TREE_VEC_LENGTH (a), current);
4386 error (" but %d required", TREE_VEC_LENGTH (t));
4387 return error_mark_node;
4390 if (current == decl)
4393 current = (TYPE_P (current)
4394 ? TYPE_CONTEXT (current)
4395 : DECL_CONTEXT (current));
4398 /* Check that the parms are used in the appropriate qualifying scopes
4399 in the declarator. */
4400 if (!comp_template_args
4402 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4405 template arguments to %qD do not match original template %qD",
4406 decl, DECL_TEMPLATE_RESULT (tmpl));
4407 if (!uses_template_parms (TI_ARGS (tinfo)))
4408 inform (input_location, "use template<> for an explicit specialization");
4409 /* Avoid crash in import_export_decl. */
4410 DECL_INTERFACE_KNOWN (decl) = 1;
4411 return error_mark_node;
4415 DECL_TEMPLATE_RESULT (tmpl) = decl;
4416 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4418 /* Push template declarations for global functions and types. Note
4419 that we do not try to push a global template friend declared in a
4420 template class; such a thing may well depend on the template
4421 parameters of the class. */
4422 if (new_template_p && !ctx
4423 && !(is_friend && template_class_depth (current_class_type) > 0))
4425 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4426 if (tmpl == error_mark_node)
4427 return error_mark_node;
4429 /* Hide template friend classes that haven't been declared yet. */
4430 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4432 DECL_ANTICIPATED (tmpl) = 1;
4433 DECL_FRIEND_P (tmpl) = 1;
4439 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4442 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4443 if (DECL_CONV_FN_P (tmpl))
4445 int depth = TMPL_PARMS_DEPTH (parms);
4447 /* It is a conversion operator. See if the type converted to
4448 depends on innermost template operands. */
4450 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4452 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4455 /* Give template template parms a DECL_CONTEXT of the template
4456 for which they are a parameter. */
4457 parms = INNERMOST_TEMPLATE_PARMS (parms);
4458 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4460 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4461 if (TREE_CODE (parm) == TEMPLATE_DECL)
4462 DECL_CONTEXT (parm) = tmpl;
4466 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4467 back to its most general template. If TMPL is a specialization,
4468 ARGS may only have the innermost set of arguments. Add the missing
4469 argument levels if necessary. */
4470 if (DECL_TEMPLATE_INFO (tmpl))
4471 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4473 info = tree_cons (tmpl, args, NULL_TREE);
4475 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4476 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4477 else if (DECL_LANG_SPECIFIC (decl))
4478 DECL_TEMPLATE_INFO (decl) = info;
4480 return DECL_TEMPLATE_RESULT (tmpl);
4484 push_template_decl (tree decl)
4486 return push_template_decl_real (decl, false);
4489 /* Called when a class template TYPE is redeclared with the indicated
4490 template PARMS, e.g.:
4492 template <class T> struct S;
4493 template <class T> struct S {}; */
4496 redeclare_class_template (tree type, tree parms)
4502 if (!TYPE_TEMPLATE_INFO (type))
4504 error ("%qT is not a template type", type);
4508 tmpl = TYPE_TI_TEMPLATE (type);
4509 if (!PRIMARY_TEMPLATE_P (tmpl))
4510 /* The type is nested in some template class. Nothing to worry
4511 about here; there are no new template parameters for the nested
4517 error ("template specifiers not specified in declaration of %qD",
4522 parms = INNERMOST_TEMPLATE_PARMS (parms);
4523 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4525 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4527 error ("redeclared with %d template parameter(s)",
4528 TREE_VEC_LENGTH (parms));
4529 inform (input_location, "previous declaration %q+D used %d template parameter(s)",
4530 tmpl, TREE_VEC_LENGTH (tmpl_parms));
4534 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4541 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4542 || TREE_VEC_ELT (parms, i) == error_mark_node)
4545 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4546 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4547 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4548 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4550 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
4552 if (tmpl_parm != error_mark_node
4553 && (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
4554 || (TREE_CODE (tmpl_parm) != TYPE_DECL
4555 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
4556 || (TREE_CODE (tmpl_parm) != PARM_DECL
4557 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
4558 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
4559 || (TREE_CODE (tmpl_parm) == PARM_DECL
4560 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
4561 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))))))
4563 error ("template parameter %q+#D", tmpl_parm);
4564 error ("redeclared here as %q#D", parm);
4568 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
4570 /* We have in [temp.param]:
4572 A template-parameter may not be given default arguments
4573 by two different declarations in the same scope. */
4574 error_at (input_location, "redefinition of default argument for %q#D", parm);
4575 inform (DECL_SOURCE_LOCATION (tmpl_parm),
4576 "original definition appeared here");
4580 if (parm_default != NULL_TREE)
4581 /* Update the previous template parameters (which are the ones
4582 that will really count) with the new default value. */
4583 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
4584 else if (tmpl_default != NULL_TREE)
4585 /* Update the new parameters, too; they'll be used as the
4586 parameters for any members. */
4587 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
4593 /* Simplify EXPR if it is a non-dependent expression. Returns the
4594 (possibly simplified) expression. */
4597 fold_non_dependent_expr (tree expr)
4599 if (expr == NULL_TREE)
4602 /* If we're in a template, but EXPR isn't value dependent, simplify
4603 it. We're supposed to treat:
4605 template <typename T> void f(T[1 + 1]);
4606 template <typename T> void f(T[2]);
4608 as two declarations of the same function, for example. */
4609 if (processing_template_decl
4610 && !type_dependent_expression_p (expr)
4611 && !value_dependent_expression_p (expr))
4613 HOST_WIDE_INT saved_processing_template_decl;
4615 saved_processing_template_decl = processing_template_decl;
4616 processing_template_decl = 0;
4617 expr = tsubst_copy_and_build (expr,
4620 /*in_decl=*/NULL_TREE,
4621 /*function_p=*/false,
4622 /*integral_constant_expression_p=*/true);
4623 processing_template_decl = saved_processing_template_decl;
4628 /* EXPR is an expression which is used in a constant-expression context.
4629 For instance, it could be a VAR_DECL with a constant initializer.
4630 Extract the innermost constant expression.
4632 This is basically a more powerful version of
4633 integral_constant_value, which can be used also in templates where
4634 initializers can maintain a syntactic rather than semantic form
4635 (even if they are non-dependent, for access-checking purposes). */
4638 fold_decl_constant_value (tree expr)
4640 tree const_expr = expr;
4643 expr = fold_non_dependent_expr (const_expr);
4644 const_expr = integral_constant_value (expr);
4646 while (expr != const_expr);
4651 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
4652 must be a function or a pointer-to-function type, as specified
4653 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
4654 and check that the resulting function has external linkage. */
4657 convert_nontype_argument_function (tree type, tree expr)
4662 fn = instantiate_type (type, fns, tf_none);
4663 if (fn == error_mark_node)
4664 return error_mark_node;
4667 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
4668 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
4669 if (TREE_CODE (fn_no_ptr) == BASELINK)
4670 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
4672 /* [temp.arg.nontype]/1
4674 A template-argument for a non-type, non-template template-parameter
4677 -- the address of an object or function with external linkage. */
4678 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
4680 error ("%qE is not a valid template argument for type %qT "
4681 "because function %qD has not external linkage",
4682 expr, type, fn_no_ptr);
4689 /* Subroutine of convert_nontype_argument.
4690 Check if EXPR of type TYPE is a valid pointer-to-member constant.
4691 Emit an error otherwise. */
4694 check_valid_ptrmem_cst_expr (tree type, tree expr)
4697 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
4699 error ("%qE is not a valid template argument for type %qT",
4701 error ("it must be a pointer-to-member of the form `&X::Y'");
4705 /* Attempt to convert the non-type template parameter EXPR to the
4706 indicated TYPE. If the conversion is successful, return the
4707 converted value. If the conversion is unsuccessful, return
4708 NULL_TREE if we issued an error message, or error_mark_node if we
4709 did not. We issue error messages for out-and-out bad template
4710 parameters, but not simply because the conversion failed, since we
4711 might be just trying to do argument deduction. Both TYPE and EXPR
4712 must be non-dependent.
4714 The conversion follows the special rules described in
4715 [temp.arg.nontype], and it is much more strict than an implicit
4718 This function is called twice for each template argument (see
4719 lookup_template_class for a more accurate description of this
4720 problem). This means that we need to handle expressions which
4721 are not valid in a C++ source, but can be created from the
4722 first call (for instance, casts to perform conversions). These
4723 hacks can go away after we fix the double coercion problem. */
4726 convert_nontype_argument (tree type, tree expr)
4730 /* Detect immediately string literals as invalid non-type argument.
4731 This special-case is not needed for correctness (we would easily
4732 catch this later), but only to provide better diagnostic for this
4733 common user mistake. As suggested by DR 100, we do not mention
4734 linkage issues in the diagnostic as this is not the point. */
4735 if (TREE_CODE (expr) == STRING_CST)
4737 error ("%qE is not a valid template argument for type %qT "
4738 "because string literals can never be used in this context",
4743 /* If we are in a template, EXPR may be non-dependent, but still
4744 have a syntactic, rather than semantic, form. For example, EXPR
4745 might be a SCOPE_REF, rather than the VAR_DECL to which the
4746 SCOPE_REF refers. Preserving the qualifying scope is necessary
4747 so that access checking can be performed when the template is
4748 instantiated -- but here we need the resolved form so that we can
4749 convert the argument. */
4750 expr = fold_non_dependent_expr (expr);
4751 if (error_operand_p (expr))
4752 return error_mark_node;
4753 expr_type = TREE_TYPE (expr);
4755 /* HACK: Due to double coercion, we can get a
4756 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
4757 which is the tree that we built on the first call (see
4758 below when coercing to reference to object or to reference to
4759 function). We just strip everything and get to the arg.
4760 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
4762 if (TREE_CODE (expr) == NOP_EXPR)
4764 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
4766 /* ??? Maybe we could use convert_from_reference here, but we
4767 would need to relax its constraints because the NOP_EXPR
4768 could actually change the type to something more cv-qualified,
4769 and this is not folded by convert_from_reference. */
4770 tree addr = TREE_OPERAND (expr, 0);
4771 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
4772 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
4773 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
4774 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4775 (TREE_TYPE (expr_type),
4776 TREE_TYPE (TREE_TYPE (addr))));
4778 expr = TREE_OPERAND (addr, 0);
4779 expr_type = TREE_TYPE (expr);
4782 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
4783 parameter is a pointer to object, through decay and
4784 qualification conversion. Let's strip everything. */
4785 else if (TYPE_PTROBV_P (type))
4788 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
4789 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
4790 /* Skip the ADDR_EXPR only if it is part of the decay for
4791 an array. Otherwise, it is part of the original argument
4792 in the source code. */
4793 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
4794 expr = TREE_OPERAND (expr, 0);
4795 expr_type = TREE_TYPE (expr);
4799 /* [temp.arg.nontype]/5, bullet 1
4801 For a non-type template-parameter of integral or enumeration type,
4802 integral promotions (_conv.prom_) and integral conversions
4803 (_conv.integral_) are applied. */
4804 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
4806 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (expr_type))
4807 return error_mark_node;
4809 expr = fold_decl_constant_value (expr);
4810 /* Notice that there are constant expressions like '4 % 0' which
4811 do not fold into integer constants. */
4812 if (TREE_CODE (expr) != INTEGER_CST)
4814 error ("%qE is not a valid template argument for type %qT "
4815 "because it is a non-constant expression", expr, type);
4819 /* At this point, an implicit conversion does what we want,
4820 because we already know that the expression is of integral
4822 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
4823 if (expr == error_mark_node)
4824 return error_mark_node;
4826 /* Conversion was allowed: fold it to a bare integer constant. */
4829 /* [temp.arg.nontype]/5, bullet 2
4831 For a non-type template-parameter of type pointer to object,
4832 qualification conversions (_conv.qual_) and the array-to-pointer
4833 conversion (_conv.array_) are applied. */
4834 else if (TYPE_PTROBV_P (type))
4836 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
4838 A template-argument for a non-type, non-template template-parameter
4839 shall be one of: [...]
4841 -- the name of a non-type template-parameter;
4842 -- the address of an object or function with external linkage, [...]
4843 expressed as "& id-expression" where the & is optional if the name
4844 refers to a function or array, or if the corresponding
4845 template-parameter is a reference.
4847 Here, we do not care about functions, as they are invalid anyway
4848 for a parameter of type pointer-to-object. */
4850 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
4851 /* Non-type template parameters are OK. */
4853 else if (TREE_CODE (expr) != ADDR_EXPR
4854 && TREE_CODE (expr_type) != ARRAY_TYPE)
4856 if (TREE_CODE (expr) == VAR_DECL)
4858 error ("%qD is not a valid template argument "
4859 "because %qD is a variable, not the address of "
4864 /* Other values, like integer constants, might be valid
4865 non-type arguments of some other type. */
4866 return error_mark_node;
4872 decl = ((TREE_CODE (expr) == ADDR_EXPR)
4873 ? TREE_OPERAND (expr, 0) : expr);
4874 if (TREE_CODE (decl) != VAR_DECL)
4876 error ("%qE is not a valid template argument of type %qT "
4877 "because %qE is not a variable",
4881 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
4883 error ("%qE is not a valid template argument of type %qT "
4884 "because %qD does not have external linkage",
4890 expr = decay_conversion (expr);
4891 if (expr == error_mark_node)
4892 return error_mark_node;
4894 expr = perform_qualification_conversions (type, expr);
4895 if (expr == error_mark_node)
4896 return error_mark_node;
4898 /* [temp.arg.nontype]/5, bullet 3
4900 For a non-type template-parameter of type reference to object, no
4901 conversions apply. The type referred to by the reference may be more
4902 cv-qualified than the (otherwise identical) type of the
4903 template-argument. The template-parameter is bound directly to the
4904 template-argument, which must be an lvalue. */
4905 else if (TYPE_REF_OBJ_P (type))
4907 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
4909 return error_mark_node;
4911 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
4913 error ("%qE is not a valid template argument for type %qT "
4914 "because of conflicts in cv-qualification", expr, type);
4918 if (!real_lvalue_p (expr))
4920 error ("%qE is not a valid template argument for type %qT "
4921 "because it is not an lvalue", expr, type);
4925 /* [temp.arg.nontype]/1
4927 A template-argument for a non-type, non-template template-parameter
4928 shall be one of: [...]
4930 -- the address of an object or function with external linkage. */
4931 if (!DECL_EXTERNAL_LINKAGE_P (expr))
4933 error ("%qE is not a valid template argument for type %qT "
4934 "because object %qD has not external linkage",
4939 expr = build_nop (type, build_address (expr));
4941 /* [temp.arg.nontype]/5, bullet 4
4943 For a non-type template-parameter of type pointer to function, only
4944 the function-to-pointer conversion (_conv.func_) is applied. If the
4945 template-argument represents a set of overloaded functions (or a
4946 pointer to such), the matching function is selected from the set
4948 else if (TYPE_PTRFN_P (type))
4950 /* If the argument is a template-id, we might not have enough
4951 context information to decay the pointer. */
4952 if (!type_unknown_p (expr_type))
4954 expr = decay_conversion (expr);
4955 if (expr == error_mark_node)
4956 return error_mark_node;
4959 expr = convert_nontype_argument_function (type, expr);
4960 if (!expr || expr == error_mark_node)
4963 if (TREE_CODE (expr) != ADDR_EXPR)
4965 error ("%qE is not a valid template argument for type %qT", expr, type);
4966 error ("it must be the address of a function with external linkage");
4970 /* [temp.arg.nontype]/5, bullet 5
4972 For a non-type template-parameter of type reference to function, no
4973 conversions apply. If the template-argument represents a set of
4974 overloaded functions, the matching function is selected from the set
4976 else if (TYPE_REFFN_P (type))
4978 if (TREE_CODE (expr) == ADDR_EXPR)
4980 error ("%qE is not a valid template argument for type %qT "
4981 "because it is a pointer", expr, type);
4982 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
4986 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
4987 if (!expr || expr == error_mark_node)
4990 expr = build_nop (type, build_address (expr));
4992 /* [temp.arg.nontype]/5, bullet 6
4994 For a non-type template-parameter of type pointer to member function,
4995 no conversions apply. If the template-argument represents a set of
4996 overloaded member functions, the matching member function is selected
4997 from the set (_over.over_). */
4998 else if (TYPE_PTRMEMFUNC_P (type))
5000 expr = instantiate_type (type, expr, tf_none);
5001 if (expr == error_mark_node)
5002 return error_mark_node;
5004 /* [temp.arg.nontype] bullet 1 says the pointer to member
5005 expression must be a pointer-to-member constant. */
5006 if (!check_valid_ptrmem_cst_expr (type, expr))
5007 return error_mark_node;
5009 /* There is no way to disable standard conversions in
5010 resolve_address_of_overloaded_function (called by
5011 instantiate_type). It is possible that the call succeeded by
5012 converting &B::I to &D::I (where B is a base of D), so we need
5013 to reject this conversion here.
5015 Actually, even if there was a way to disable standard conversions,
5016 it would still be better to reject them here so that we can
5017 provide a superior diagnostic. */
5018 if (!same_type_p (TREE_TYPE (expr), type))
5020 /* Make sure we are just one standard conversion off. */
5021 gcc_assert (can_convert (type, TREE_TYPE (expr)));
5022 error ("%qE is not a valid template argument for type %qT "
5023 "because it is of type %qT", expr, type,
5025 inform (input_location, "standard conversions are not allowed in this context");
5029 /* [temp.arg.nontype]/5, bullet 7
5031 For a non-type template-parameter of type pointer to data member,
5032 qualification conversions (_conv.qual_) are applied. */
5033 else if (TYPE_PTRMEM_P (type))
5035 /* [temp.arg.nontype] bullet 1 says the pointer to member
5036 expression must be a pointer-to-member constant. */
5037 if (!check_valid_ptrmem_cst_expr (type, expr))
5038 return error_mark_node;
5040 expr = perform_qualification_conversions (type, expr);
5041 if (expr == error_mark_node)
5044 /* A template non-type parameter must be one of the above. */
5048 /* Sanity check: did we actually convert the argument to the
5050 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
5054 /* Subroutine of coerce_template_template_parms, which returns 1 if
5055 PARM_PARM and ARG_PARM match using the rule for the template
5056 parameters of template template parameters. Both PARM and ARG are
5057 template parameters; the rest of the arguments are the same as for
5058 coerce_template_template_parms.
5061 coerce_template_template_parm (tree parm,
5063 tsubst_flags_t complain,
5067 if (arg == NULL_TREE || arg == error_mark_node
5068 || parm == NULL_TREE || parm == error_mark_node)
5071 if (TREE_CODE (arg) != TREE_CODE (parm))
5074 switch (TREE_CODE (parm))
5077 /* We encounter instantiations of templates like
5078 template <template <template <class> class> class TT>
5081 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5082 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5084 if (!coerce_template_template_parms
5085 (parmparm, argparm, complain, in_decl, outer_args))
5091 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
5092 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5093 /* Argument is a parameter pack but parameter is not. */
5098 /* The tsubst call is used to handle cases such as
5100 template <int> class C {};
5101 template <class T, template <T> class TT> class D {};
5104 i.e. the parameter list of TT depends on earlier parameters. */
5105 if (!uses_template_parms (TREE_TYPE (arg))
5107 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
5111 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
5112 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5113 /* Argument is a parameter pack but parameter is not. */
5126 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
5127 template template parameters. Both PARM_PARMS and ARG_PARMS are
5128 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
5131 Consider the example:
5132 template <class T> class A;
5133 template<template <class U> class TT> class B;
5135 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
5136 the parameters to A, and OUTER_ARGS contains A. */
5139 coerce_template_template_parms (tree parm_parms,
5141 tsubst_flags_t complain,
5145 int nparms, nargs, i;
5149 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
5150 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
5152 nparms = TREE_VEC_LENGTH (parm_parms);
5153 nargs = TREE_VEC_LENGTH (arg_parms);
5155 /* Determine whether we have a parameter pack at the end of the
5156 template template parameter's template parameter list. */
5157 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
5159 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
5161 if (parm == error_mark_node)
5164 switch (TREE_CODE (parm))
5168 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5173 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5183 && !(variadic_p && nargs >= nparms - 1))
5186 /* Check all of the template parameters except the parameter pack at
5187 the end (if any). */
5188 for (i = 0; i < nparms - variadic_p; ++i)
5190 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
5191 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5194 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5195 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5197 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5205 /* Check each of the template parameters in the template
5206 argument against the template parameter pack at the end of
5207 the template template parameter. */
5208 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
5211 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5213 for (; i < nargs; ++i)
5215 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5218 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5220 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5229 /* Verifies that the deduced template arguments (in TARGS) for the
5230 template template parameters (in TPARMS) represent valid bindings,
5231 by comparing the template parameter list of each template argument
5232 to the template parameter list of its corresponding template
5233 template parameter, in accordance with DR150. This
5234 routine can only be called after all template arguments have been
5235 deduced. It will return TRUE if all of the template template
5236 parameter bindings are okay, FALSE otherwise. */
5238 template_template_parm_bindings_ok_p (tree tparms, tree targs)
5240 int i, ntparms = TREE_VEC_LENGTH (tparms);
5243 /* We're dealing with template parms in this process. */
5244 ++processing_template_decl;
5246 targs = INNERMOST_TEMPLATE_ARGS (targs);
5248 for (i = 0; i < ntparms; ++i)
5250 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
5251 tree targ = TREE_VEC_ELT (targs, i);
5253 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
5255 tree packed_args = NULL_TREE;
5258 if (ARGUMENT_PACK_P (targ))
5260 /* Look inside the argument pack. */
5261 packed_args = ARGUMENT_PACK_ARGS (targ);
5262 len = TREE_VEC_LENGTH (packed_args);
5265 for (idx = 0; idx < len; ++idx)
5267 tree targ_parms = NULL_TREE;
5270 /* Extract the next argument from the argument
5272 targ = TREE_VEC_ELT (packed_args, idx);
5274 if (PACK_EXPANSION_P (targ))
5275 /* Look at the pattern of the pack expansion. */
5276 targ = PACK_EXPANSION_PATTERN (targ);
5278 /* Extract the template parameters from the template
5280 if (TREE_CODE (targ) == TEMPLATE_DECL)
5281 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
5282 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
5283 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
5285 /* Verify that we can coerce the template template
5286 parameters from the template argument to the template
5287 parameter. This requires an exact match. */
5289 && !coerce_template_template_parms
5290 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
5305 --processing_template_decl;
5309 /* Convert the indicated template ARG as necessary to match the
5310 indicated template PARM. Returns the converted ARG, or
5311 error_mark_node if the conversion was unsuccessful. Error and
5312 warning messages are issued under control of COMPLAIN. This
5313 conversion is for the Ith parameter in the parameter list. ARGS is
5314 the full set of template arguments deduced so far. */
5317 convert_template_argument (tree parm,
5320 tsubst_flags_t complain,
5326 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
5328 if (TREE_CODE (arg) == TREE_LIST
5329 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
5331 /* The template argument was the name of some
5332 member function. That's usually
5333 invalid, but static members are OK. In any
5334 case, grab the underlying fields/functions
5335 and issue an error later if required. */
5336 orig_arg = TREE_VALUE (arg);
5337 TREE_TYPE (arg) = unknown_type_node;
5342 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
5343 requires_type = (TREE_CODE (parm) == TYPE_DECL
5344 || requires_tmpl_type);
5346 /* When determining whether an argument pack expansion is a template,
5347 look at the pattern. */
5348 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
5349 arg = PACK_EXPANSION_PATTERN (arg);
5352 ((TREE_CODE (arg) == TEMPLATE_DECL
5353 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
5354 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5355 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
5358 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5359 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
5360 arg = TYPE_STUB_DECL (arg);
5362 is_type = TYPE_P (arg) || is_tmpl_type;
5364 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
5365 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
5367 permerror (input_location, "to refer to a type member of a template parameter, "
5368 "use %<typename %E%>", orig_arg);
5370 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
5371 TREE_OPERAND (arg, 1),
5373 complain & tf_error);
5377 if (is_type != requires_type)
5381 if (complain & tf_error)
5383 error ("type/value mismatch at argument %d in template "
5384 "parameter list for %qD",
5387 error (" expected a constant of type %qT, got %qT",
5389 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
5390 else if (requires_tmpl_type)
5391 error (" expected a class template, got %qE", orig_arg);
5393 error (" expected a type, got %qE", orig_arg);
5396 return error_mark_node;
5398 if (is_tmpl_type ^ requires_tmpl_type)
5400 if (in_decl && (complain & tf_error))
5402 error ("type/value mismatch at argument %d in template "
5403 "parameter list for %qD",
5406 error (" expected a type, got %qT", DECL_NAME (arg));
5408 error (" expected a class template, got %qT", orig_arg);
5410 return error_mark_node;
5415 if (requires_tmpl_type)
5417 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
5418 /* The number of argument required is not known yet.
5419 Just accept it for now. */
5420 val = TREE_TYPE (arg);
5423 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5426 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5428 if (coerce_template_template_parms (parmparm, argparm,
5434 /* TEMPLATE_TEMPLATE_PARM node is preferred over
5436 if (val != error_mark_node)
5438 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
5439 val = TREE_TYPE (val);
5440 else if (TREE_CODE (val) == TYPE_PACK_EXPANSION
5441 && DECL_TEMPLATE_TEMPLATE_PARM_P (arg))
5443 val = TREE_TYPE (arg);
5444 val = make_pack_expansion (val);
5450 if (in_decl && (complain & tf_error))
5452 error ("type/value mismatch at argument %d in "
5453 "template parameter list for %qD",
5455 error (" expected a template of type %qD, got %qD",
5459 val = error_mark_node;
5465 /* We only form one instance of each template specialization.
5466 Therefore, if we use a non-canonical variant (i.e., a
5467 typedef), any future messages referring to the type will use
5468 the typedef, which is confusing if those future uses do not
5469 themselves also use the typedef. */
5471 val = strip_typedefs (val);
5475 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
5477 if (invalid_nontype_parm_type_p (t, complain))
5478 return error_mark_node;
5480 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
5482 if (same_type_p (t, TREE_TYPE (orig_arg)))
5486 /* Not sure if this is reachable, but it doesn't hurt
5488 error ("type mismatch in nontype parameter pack");
5489 val = error_mark_node;
5492 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
5493 /* We used to call digest_init here. However, digest_init
5494 will report errors, which we don't want when complain
5495 is zero. More importantly, digest_init will try too
5496 hard to convert things: for example, `0' should not be
5497 converted to pointer type at this point according to
5498 the standard. Accepting this is not merely an
5499 extension, since deciding whether or not these
5500 conversions can occur is part of determining which
5501 function template to call, or whether a given explicit
5502 argument specification is valid. */
5503 val = convert_nontype_argument (t, orig_arg);
5507 if (val == NULL_TREE)
5508 val = error_mark_node;
5509 else if (val == error_mark_node && (complain & tf_error))
5510 error ("could not convert template argument %qE to %qT", orig_arg, t);
5516 /* Coerces the remaining template arguments in INNER_ARGS (from
5517 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
5518 Returns the coerced argument pack. PARM_IDX is the position of this
5519 parameter in the template parameter list. ARGS is the original
5520 template argument list. */
5522 coerce_template_parameter_pack (tree parms,
5530 tsubst_flags_t complain)
5532 tree parm = TREE_VEC_ELT (parms, parm_idx);
5533 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5536 tree packed_types = NULL_TREE;
5538 if (arg_idx > nargs)
5541 packed_args = make_tree_vec (nargs - arg_idx);
5543 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
5544 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
5546 /* When the template parameter is a non-type template
5547 parameter pack whose type uses parameter packs, we need
5548 to look at each of the template arguments
5549 separately. Build a vector of the types for these
5550 non-type template parameters in PACKED_TYPES. */
5552 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
5553 packed_types = tsubst_pack_expansion (expansion, args,
5556 if (packed_types == error_mark_node)
5557 return error_mark_node;
5559 /* Check that we have the right number of arguments. */
5561 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
5562 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
5565 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
5566 error ("wrong number of template arguments (%d, should be %d)",
5567 nargs, needed_parms);
5568 return error_mark_node;
5571 /* If we aren't able to check the actual arguments now
5572 (because they haven't been expanded yet), we can at least
5573 verify that all of the types used for the non-type
5574 template parameter pack are, in fact, valid for non-type
5575 template parameters. */
5577 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
5579 int j, len = TREE_VEC_LENGTH (packed_types);
5580 for (j = 0; j < len; ++j)
5582 tree t = TREE_VEC_ELT (packed_types, j);
5583 if (invalid_nontype_parm_type_p (t, complain))
5584 return error_mark_node;
5589 /* Convert the remaining arguments, which will be a part of the
5590 parameter pack "parm". */
5591 for (; arg_idx < nargs; ++arg_idx)
5593 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
5594 tree actual_parm = TREE_VALUE (parm);
5596 if (packed_types && !PACK_EXPANSION_P (arg))
5598 /* When we have a vector of types (corresponding to the
5599 non-type template parameter pack that uses parameter
5600 packs in its type, as mention above), and the
5601 argument is not an expansion (which expands to a
5602 currently unknown number of arguments), clone the
5603 parm and give it the next type in PACKED_TYPES. */
5604 actual_parm = copy_node (actual_parm);
5605 TREE_TYPE (actual_parm) =
5606 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
5609 if (arg != error_mark_node)
5610 arg = convert_template_argument (actual_parm,
5611 arg, new_args, complain, parm_idx,
5613 if (arg == error_mark_node)
5615 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
5618 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
5619 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
5620 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
5623 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
5624 TREE_TYPE (argument_pack)
5625 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
5626 TREE_CONSTANT (argument_pack) = 1;
5629 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
5630 return argument_pack;
5633 /* Convert all template arguments to their appropriate types, and
5634 return a vector containing the innermost resulting template
5635 arguments. If any error occurs, return error_mark_node. Error and
5636 warning messages are issued under control of COMPLAIN.
5638 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
5639 for arguments not specified in ARGS. Otherwise, if
5640 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
5641 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
5642 USE_DEFAULT_ARGS is false, then all arguments must be specified in
5646 coerce_template_parms (tree parms,
5649 tsubst_flags_t complain,
5650 bool require_all_args,
5651 bool use_default_args)
5653 int nparms, nargs, parm_idx, arg_idx, lost = 0;
5656 tree new_inner_args;
5657 int saved_unevaluated_operand;
5658 int saved_inhibit_evaluation_warnings;
5660 /* When used as a boolean value, indicates whether this is a
5661 variadic template parameter list. Since it's an int, we can also
5662 subtract it from nparms to get the number of non-variadic
5666 nparms = TREE_VEC_LENGTH (parms);
5668 /* Determine if there are any parameter packs. */
5669 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
5671 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
5672 if (template_parameter_pack_p (tparm))
5676 inner_args = INNERMOST_TEMPLATE_ARGS (args);
5677 /* If there are 0 or 1 parameter packs, we need to expand any argument
5678 packs so that we can deduce a parameter pack from some non-packed args
5679 followed by an argument pack, as in variadic85.C. If there are more
5680 than that, we need to leave argument packs intact so the arguments are
5681 assigned to the right parameter packs. This should only happen when
5682 dealing with a nested class inside a partial specialization of a class
5683 template, as in variadic92.C. */
5684 if (variadic_p <= 1)
5685 inner_args = expand_template_argument_pack (inner_args);
5687 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5688 if ((nargs > nparms && !variadic_p)
5689 || (nargs < nparms - variadic_p
5691 && (!use_default_args
5692 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
5693 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
5695 if (complain & tf_error)
5697 const char *or_more = "";
5700 or_more = " or more";
5704 error ("wrong number of template arguments (%d, should be %d%s)",
5705 nargs, nparms, or_more);
5708 error ("provided for %q+D", in_decl);
5711 return error_mark_node;
5714 /* We need to evaluate the template arguments, even though this
5715 template-id may be nested within a "sizeof". */
5716 saved_unevaluated_operand = cp_unevaluated_operand;
5717 cp_unevaluated_operand = 0;
5718 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
5719 c_inhibit_evaluation_warnings = 0;
5720 new_inner_args = make_tree_vec (nparms);
5721 new_args = add_outermost_template_args (args, new_inner_args);
5722 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
5727 /* Get the Ith template parameter. */
5728 parm = TREE_VEC_ELT (parms, parm_idx);
5730 if (parm == error_mark_node)
5732 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
5736 /* Calculate the next argument. */
5737 if (arg_idx < nargs)
5738 arg = TREE_VEC_ELT (inner_args, arg_idx);
5742 if (template_parameter_pack_p (TREE_VALUE (parm))
5743 && !(arg && ARGUMENT_PACK_P (arg)))
5745 /* All remaining arguments will be placed in the
5746 template parameter pack PARM. */
5747 arg = coerce_template_parameter_pack (parms, parm_idx, args,
5748 inner_args, arg_idx,
5752 /* Store this argument. */
5753 if (arg == error_mark_node)
5755 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
5757 /* We are done with all of the arguments. */
5764 if (PACK_EXPANSION_P (arg))
5766 if (complain & tf_error)
5768 /* FIXME this restriction was removed by N2555; see
5770 /* If ARG is a pack expansion, but PARM is not a
5771 template parameter pack (if it were, we would have
5772 handled it above), we're trying to expand into a
5773 fixed-length argument list. */
5774 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
5775 sorry ("cannot expand %<%E%> into a fixed-length "
5776 "argument list", arg);
5778 sorry ("cannot expand %<%T%> into a fixed-length "
5779 "argument list", arg);
5781 return error_mark_node;
5784 else if (require_all_args)
5785 /* There must be a default arg in this case. */
5786 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
5791 if (arg == error_mark_node)
5793 if (complain & tf_error)
5794 error ("template argument %d is invalid", arg_idx + 1);
5797 /* This only occurs if there was an error in the template
5798 parameter list itself (which we would already have
5799 reported) that we are trying to recover from, e.g., a class
5800 template with a parameter list such as
5801 template<typename..., typename>. */
5802 return error_mark_node;
5804 arg = convert_template_argument (TREE_VALUE (parm),
5805 arg, new_args, complain,
5808 if (arg == error_mark_node)
5810 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
5812 cp_unevaluated_operand = saved_unevaluated_operand;
5813 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
5816 return error_mark_node;
5818 return new_inner_args;
5821 /* Returns 1 if template args OT and NT are equivalent. */
5824 template_args_equal (tree ot, tree nt)
5829 if (TREE_CODE (nt) == TREE_VEC)
5830 /* For member templates */
5831 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
5832 else if (PACK_EXPANSION_P (ot))
5833 return PACK_EXPANSION_P (nt)
5834 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
5835 PACK_EXPANSION_PATTERN (nt));
5836 else if (ARGUMENT_PACK_P (ot))
5841 if (!ARGUMENT_PACK_P (nt))
5844 opack = ARGUMENT_PACK_ARGS (ot);
5845 npack = ARGUMENT_PACK_ARGS (nt);
5846 len = TREE_VEC_LENGTH (opack);
5847 if (TREE_VEC_LENGTH (npack) != len)
5849 for (i = 0; i < len; ++i)
5850 if (!template_args_equal (TREE_VEC_ELT (opack, i),
5851 TREE_VEC_ELT (npack, i)))
5855 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
5857 /* We get here probably because we are in the middle of substituting
5858 into the pattern of a pack expansion. In that case the
5859 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
5860 interested in. So we want to use the initial pack argument for
5862 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
5863 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
5864 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
5865 return template_args_equal (ot, nt);
5867 else if (TYPE_P (nt))
5868 return TYPE_P (ot) && same_type_p (ot, nt);
5869 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
5872 return cp_tree_equal (ot, nt);
5875 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
5876 of template arguments. Returns 0 otherwise. */
5879 comp_template_args (tree oldargs, tree newargs)
5883 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
5886 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
5888 tree nt = TREE_VEC_ELT (newargs, i);
5889 tree ot = TREE_VEC_ELT (oldargs, i);
5891 if (! template_args_equal (ot, nt))
5898 add_pending_template (tree d)
5900 tree ti = (TYPE_P (d)
5901 ? CLASSTYPE_TEMPLATE_INFO (d)
5902 : DECL_TEMPLATE_INFO (d));
5903 struct pending_template *pt;
5906 if (TI_PENDING_TEMPLATE_FLAG (ti))
5909 /* We are called both from instantiate_decl, where we've already had a
5910 tinst_level pushed, and instantiate_template, where we haven't.
5912 level = !current_tinst_level || current_tinst_level->decl != d;
5915 push_tinst_level (d);
5917 pt = GGC_NEW (struct pending_template);
5919 pt->tinst = current_tinst_level;
5920 if (last_pending_template)
5921 last_pending_template->next = pt;
5923 pending_templates = pt;
5925 last_pending_template = pt;
5927 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
5934 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
5935 ARGLIST. Valid choices for FNS are given in the cp-tree.def
5936 documentation for TEMPLATE_ID_EXPR. */
5939 lookup_template_function (tree fns, tree arglist)
5943 if (fns == error_mark_node || arglist == error_mark_node)
5944 return error_mark_node;
5946 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
5947 gcc_assert (fns && (is_overloaded_fn (fns)
5948 || TREE_CODE (fns) == IDENTIFIER_NODE));
5950 if (BASELINK_P (fns))
5952 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
5954 BASELINK_FUNCTIONS (fns),
5959 type = TREE_TYPE (fns);
5960 if (TREE_CODE (fns) == OVERLOAD || !type)
5961 type = unknown_type_node;
5963 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
5966 /* Within the scope of a template class S<T>, the name S gets bound
5967 (in build_self_reference) to a TYPE_DECL for the class, not a
5968 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
5969 or one of its enclosing classes, and that type is a template,
5970 return the associated TEMPLATE_DECL. Otherwise, the original
5971 DECL is returned. */
5974 maybe_get_template_decl_from_type_decl (tree decl)
5976 return (decl != NULL_TREE
5977 && TREE_CODE (decl) == TYPE_DECL
5978 && DECL_ARTIFICIAL (decl)
5979 && CLASS_TYPE_P (TREE_TYPE (decl))
5980 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
5981 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
5984 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
5985 parameters, find the desired type.
5987 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
5989 IN_DECL, if non-NULL, is the template declaration we are trying to
5992 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
5993 the class we are looking up.
5995 Issue error and warning messages under control of COMPLAIN.
5997 If the template class is really a local class in a template
5998 function, then the FUNCTION_CONTEXT is the function in which it is
6001 ??? Note that this function is currently called *twice* for each
6002 template-id: the first time from the parser, while creating the
6003 incomplete type (finish_template_type), and the second type during the
6004 real instantiation (instantiate_template_class). This is surely something
6005 that we want to avoid. It also causes some problems with argument
6006 coercion (see convert_nontype_argument for more information on this). */
6009 lookup_template_class (tree d1,
6014 tsubst_flags_t complain)
6016 tree templ = NULL_TREE, parmlist;
6023 timevar_push (TV_NAME_LOOKUP);
6025 if (TREE_CODE (d1) == IDENTIFIER_NODE)
6027 tree value = innermost_non_namespace_value (d1);
6028 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
6033 push_decl_namespace (context);
6034 templ = lookup_name (d1);
6035 templ = maybe_get_template_decl_from_type_decl (templ);
6037 pop_decl_namespace ();
6040 context = DECL_CONTEXT (templ);
6042 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
6044 tree type = TREE_TYPE (d1);
6046 /* If we are declaring a constructor, say A<T>::A<T>, we will get
6047 an implicit typename for the second A. Deal with it. */
6048 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
6049 type = TREE_TYPE (type);
6051 if (CLASSTYPE_TEMPLATE_INFO (type))
6053 templ = CLASSTYPE_TI_TEMPLATE (type);
6054 d1 = DECL_NAME (templ);
6057 else if (TREE_CODE (d1) == ENUMERAL_TYPE
6058 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
6060 templ = TYPE_TI_TEMPLATE (d1);
6061 d1 = DECL_NAME (templ);
6063 else if (TREE_CODE (d1) == TEMPLATE_DECL
6064 && DECL_TEMPLATE_RESULT (d1)
6065 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
6068 d1 = DECL_NAME (templ);
6069 context = DECL_CONTEXT (templ);
6072 /* Issue an error message if we didn't find a template. */
6075 if (complain & tf_error)
6076 error ("%qT is not a template", d1);
6077 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6080 if (TREE_CODE (templ) != TEMPLATE_DECL
6081 /* Make sure it's a user visible template, if it was named by
6083 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
6084 && !PRIMARY_TEMPLATE_P (templ)))
6086 if (complain & tf_error)
6088 error ("non-template type %qT used as a template", d1);
6090 error ("for template declaration %q+D", in_decl);
6092 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6095 complain &= ~tf_user;
6097 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
6099 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
6100 template arguments */
6106 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
6108 /* Consider an example where a template template parameter declared as
6110 template <class T, class U = std::allocator<T> > class TT
6112 The template parameter level of T and U are one level larger than
6113 of TT. To proper process the default argument of U, say when an
6114 instantiation `TT<int>' is seen, we need to build the full
6115 arguments containing {int} as the innermost level. Outer levels,
6116 available when not appearing as default template argument, can be
6117 obtained from the arguments of the enclosing template.
6119 Suppose that TT is later substituted with std::vector. The above
6120 instantiation is `TT<int, std::allocator<T> >' with TT at
6121 level 1, and T at level 2, while the template arguments at level 1
6122 becomes {std::vector} and the inner level 2 is {int}. */
6124 outer = DECL_CONTEXT (templ);
6126 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
6127 else if (current_template_parms)
6128 /* This is an argument of the current template, so we haven't set
6129 DECL_CONTEXT yet. */
6130 outer = current_template_args ();
6133 arglist = add_to_template_args (outer, arglist);
6135 arglist2 = coerce_template_parms (parmlist, arglist, templ,
6137 /*require_all_args=*/true,
6138 /*use_default_args=*/true);
6139 if (arglist2 == error_mark_node
6140 || (!uses_template_parms (arglist2)
6141 && check_instantiated_args (templ, arglist2, complain)))
6142 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6144 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
6145 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
6149 tree template_type = TREE_TYPE (templ);
6152 tree found = NULL_TREE;
6155 int is_partial_instantiation;
6157 gen_tmpl = most_general_template (templ);
6158 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
6159 parm_depth = TMPL_PARMS_DEPTH (parmlist);
6160 arg_depth = TMPL_ARGS_DEPTH (arglist);
6162 if (arg_depth == 1 && parm_depth > 1)
6164 /* We've been given an incomplete set of template arguments.
6167 template <class T> struct S1 {
6168 template <class U> struct S2 {};
6169 template <class U> struct S2<U*> {};
6172 we will be called with an ARGLIST of `U*', but the
6173 TEMPLATE will be `template <class T> template
6174 <class U> struct S1<T>::S2'. We must fill in the missing
6177 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
6179 arg_depth = TMPL_ARGS_DEPTH (arglist);
6182 /* Now we should have enough arguments. */
6183 gcc_assert (parm_depth == arg_depth);
6185 /* From here on, we're only interested in the most general
6188 /* Calculate the BOUND_ARGS. These will be the args that are
6189 actually tsubst'd into the definition to create the
6193 /* We have multiple levels of arguments to coerce, at once. */
6195 int saved_depth = TMPL_ARGS_DEPTH (arglist);
6197 tree bound_args = make_tree_vec (parm_depth);
6199 for (i = saved_depth,
6200 t = DECL_TEMPLATE_PARMS (gen_tmpl);
6201 i > 0 && t != NULL_TREE;
6202 --i, t = TREE_CHAIN (t))
6204 tree a = coerce_template_parms (TREE_VALUE (t),
6207 /*require_all_args=*/true,
6208 /*use_default_args=*/true);
6210 /* Don't process further if one of the levels fails. */
6211 if (a == error_mark_node)
6213 /* Restore the ARGLIST to its full size. */
6214 TREE_VEC_LENGTH (arglist) = saved_depth;
6215 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6218 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
6220 /* We temporarily reduce the length of the ARGLIST so
6221 that coerce_template_parms will see only the arguments
6222 corresponding to the template parameters it is
6224 TREE_VEC_LENGTH (arglist)--;
6227 /* Restore the ARGLIST to its full size. */
6228 TREE_VEC_LENGTH (arglist) = saved_depth;
6230 arglist = bound_args;
6234 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
6235 INNERMOST_TEMPLATE_ARGS (arglist),
6238 /*require_all_args=*/true,
6239 /*use_default_args=*/true);
6241 if (arglist == error_mark_node)
6242 /* We were unable to bind the arguments. */
6243 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6245 /* In the scope of a template class, explicit references to the
6246 template class refer to the type of the template, not any
6247 instantiation of it. For example, in:
6249 template <class T> class C { void f(C<T>); }
6251 the `C<T>' is just the same as `C'. Outside of the
6252 class, however, such a reference is an instantiation. */
6254 || !PRIMARY_TEMPLATE_P (gen_tmpl)
6255 || currently_open_class (template_type))
6256 /* comp_template_args is expensive, check it last. */
6257 && comp_template_args (TYPE_TI_ARGS (template_type),
6259 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, template_type);
6261 /* If we already have this specialization, return it. */
6262 elt.tmpl = gen_tmpl;
6264 hash = hash_specialization (&elt);
6265 entry = (spec_entry *) htab_find_with_hash (type_specializations,
6269 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, entry->spec);
6271 /* This type is a "partial instantiation" if any of the template
6272 arguments still involve template parameters. Note that we set
6273 IS_PARTIAL_INSTANTIATION for partial specializations as
6275 is_partial_instantiation = uses_template_parms (arglist);
6277 /* If the deduced arguments are invalid, then the binding
6279 if (!is_partial_instantiation
6280 && check_instantiated_args (gen_tmpl,
6281 INNERMOST_TEMPLATE_ARGS (arglist),
6283 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6285 if (!is_partial_instantiation
6286 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6287 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
6288 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
6290 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
6291 DECL_NAME (gen_tmpl),
6292 /*tag_scope=*/ts_global);
6293 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
6296 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
6299 context = global_namespace;
6301 /* Create the type. */
6302 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
6304 if (!is_partial_instantiation)
6306 set_current_access_from_decl (TYPE_NAME (template_type));
6307 t = start_enum (TYPE_IDENTIFIER (template_type),
6308 tsubst (ENUM_UNDERLYING_TYPE (template_type),
6309 arglist, complain, in_decl),
6310 SCOPED_ENUM_P (template_type));
6314 /* We don't want to call start_enum for this type, since
6315 the values for the enumeration constants may involve
6316 template parameters. And, no one should be interested
6317 in the enumeration constants for such a type. */
6318 t = cxx_make_type (ENUMERAL_TYPE);
6319 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
6324 t = make_class_type (TREE_CODE (template_type));
6325 CLASSTYPE_DECLARED_CLASS (t)
6326 = CLASSTYPE_DECLARED_CLASS (template_type);
6327 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
6328 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
6330 /* A local class. Make sure the decl gets registered properly. */
6331 if (context == current_function_decl)
6332 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
6334 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
6335 /* This instantiation is another name for the primary
6336 template type. Set the TYPE_CANONICAL field
6338 TYPE_CANONICAL (t) = template_type;
6339 else if (any_template_arguments_need_structural_equality_p (arglist))
6340 /* Some of the template arguments require structural
6341 equality testing, so this template class requires
6342 structural equality testing. */
6343 SET_TYPE_STRUCTURAL_EQUALITY (t);
6346 /* If we called start_enum or pushtag above, this information
6347 will already be set up. */
6350 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
6352 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
6353 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
6354 TYPE_STUB_DECL (t) = type_decl;
6355 DECL_SOURCE_LOCATION (type_decl)
6356 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
6359 type_decl = TYPE_NAME (t);
6361 TREE_PRIVATE (type_decl)
6362 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
6363 TREE_PROTECTED (type_decl)
6364 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
6365 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
6367 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
6368 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
6371 /* Set up the template information. We have to figure out which
6372 template is the immediate parent if this is a full
6374 if (parm_depth == 1 || is_partial_instantiation
6375 || !PRIMARY_TEMPLATE_P (gen_tmpl))
6376 /* This case is easy; there are no member templates involved. */
6380 /* This is a full instantiation of a member template. Find
6381 the partial instantiation of which this is an instance. */
6383 /* Temporarily reduce by one the number of levels in the ARGLIST
6384 so as to avoid comparing the last set of arguments. */
6385 TREE_VEC_LENGTH (arglist)--;
6386 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
6387 TREE_VEC_LENGTH (arglist)++;
6388 found = CLASSTYPE_TI_TEMPLATE (found);
6391 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
6394 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
6395 &elt, hash, INSERT);
6396 *slot = GGC_NEW (spec_entry);
6399 /* Note this use of the partial instantiation so we can check it
6400 later in maybe_process_partial_specialization. */
6401 DECL_TEMPLATE_INSTANTIATIONS (templ)
6402 = tree_cons (arglist, t,
6403 DECL_TEMPLATE_INSTANTIATIONS (templ));
6405 if (TREE_CODE (t) == ENUMERAL_TYPE
6406 && !is_partial_instantiation)
6407 /* Now that the type has been registered on the instantiations
6408 list, we set up the enumerators. Because the enumeration
6409 constants may involve the enumeration type itself, we make
6410 sure to register the type first, and then create the
6411 constants. That way, doing tsubst_expr for the enumeration
6412 constants won't result in recursive calls here; we'll find
6413 the instantiation and exit above. */
6414 tsubst_enum (template_type, t, arglist);
6416 if (is_partial_instantiation)
6417 /* If the type makes use of template parameters, the
6418 code that generates debugging information will crash. */
6419 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
6421 /* Possibly limit visibility based on template args. */
6422 TREE_PUBLIC (type_decl) = 1;
6423 determine_visibility (type_decl);
6425 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
6427 timevar_pop (TV_NAME_LOOKUP);
6434 /* True when we should also visit template parameters that occur in
6435 non-deduced contexts. */
6436 bool include_nondeduced_p;
6437 struct pointer_set_t *visited;
6440 /* Called from for_each_template_parm via walk_tree. */
6443 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
6446 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
6447 tree_fn_t fn = pfd->fn;
6448 void *data = pfd->data;
6451 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
6452 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
6453 pfd->include_nondeduced_p))
6454 return error_mark_node;
6456 switch (TREE_CODE (t))
6459 if (TYPE_PTRMEMFUNC_P (t))
6465 if (!TYPE_TEMPLATE_INFO (t))
6467 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
6468 fn, data, pfd->visited,
6469 pfd->include_nondeduced_p))
6470 return error_mark_node;
6474 if (for_each_template_parm (TYPE_MIN_VALUE (t),
6475 fn, data, pfd->visited,
6476 pfd->include_nondeduced_p)
6477 || for_each_template_parm (TYPE_MAX_VALUE (t),
6478 fn, data, pfd->visited,
6479 pfd->include_nondeduced_p))
6480 return error_mark_node;
6484 /* Since we're not going to walk subtrees, we have to do this
6486 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
6487 pfd->visited, pfd->include_nondeduced_p))
6488 return error_mark_node;
6492 /* Check the return type. */
6493 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6494 pfd->include_nondeduced_p))
6495 return error_mark_node;
6497 /* Check the parameter types. Since default arguments are not
6498 instantiated until they are needed, the TYPE_ARG_TYPES may
6499 contain expressions that involve template parameters. But,
6500 no-one should be looking at them yet. And, once they're
6501 instantiated, they don't contain template parameters, so
6502 there's no point in looking at them then, either. */
6506 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
6507 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
6508 pfd->visited, pfd->include_nondeduced_p))
6509 return error_mark_node;
6511 /* Since we've already handled the TYPE_ARG_TYPES, we don't
6512 want walk_tree walking into them itself. */
6518 if (pfd->include_nondeduced_p
6519 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
6521 pfd->include_nondeduced_p))
6522 return error_mark_node;
6527 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
6528 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
6529 pfd->visited, pfd->include_nondeduced_p))
6530 return error_mark_node;
6535 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
6536 && for_each_template_parm (DECL_INITIAL (t), fn, data,
6537 pfd->visited, pfd->include_nondeduced_p))
6538 return error_mark_node;
6539 if (DECL_CONTEXT (t)
6540 && pfd->include_nondeduced_p
6541 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
6542 pfd->visited, pfd->include_nondeduced_p))
6543 return error_mark_node;
6546 case BOUND_TEMPLATE_TEMPLATE_PARM:
6547 /* Record template parameters such as `T' inside `TT<T>'. */
6548 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
6549 pfd->include_nondeduced_p))
6550 return error_mark_node;
6553 case TEMPLATE_TEMPLATE_PARM:
6554 case TEMPLATE_TYPE_PARM:
6555 case TEMPLATE_PARM_INDEX:
6556 if (fn && (*fn)(t, data))
6557 return error_mark_node;
6559 return error_mark_node;
6563 /* A template template parameter is encountered. */
6564 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
6565 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6566 pfd->include_nondeduced_p))
6567 return error_mark_node;
6569 /* Already substituted template template parameter */
6575 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
6577 pfd->include_nondeduced_p))
6578 return error_mark_node;
6582 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
6583 && pfd->include_nondeduced_p
6584 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
6585 (TREE_TYPE (t)), fn, data,
6586 pfd->visited, pfd->include_nondeduced_p))
6587 return error_mark_node;
6592 /* If there's no type, then this thing must be some expression
6593 involving template parameters. */
6594 if (!fn && !TREE_TYPE (t))
6595 return error_mark_node;
6600 case REINTERPRET_CAST_EXPR:
6601 case CONST_CAST_EXPR:
6602 case STATIC_CAST_EXPR:
6603 case DYNAMIC_CAST_EXPR:
6607 case PSEUDO_DTOR_EXPR:
6609 return error_mark_node;
6616 /* We didn't find any template parameters we liked. */
6620 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
6621 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
6622 call FN with the parameter and the DATA.
6623 If FN returns nonzero, the iteration is terminated, and
6624 for_each_template_parm returns 1. Otherwise, the iteration
6625 continues. If FN never returns a nonzero value, the value
6626 returned by for_each_template_parm is 0. If FN is NULL, it is
6627 considered to be the function which always returns 1.
6629 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
6630 parameters that occur in non-deduced contexts. When false, only
6631 visits those template parameters that can be deduced. */
6634 for_each_template_parm (tree t, tree_fn_t fn, void* data,
6635 struct pointer_set_t *visited,
6636 bool include_nondeduced_p)
6638 struct pair_fn_data pfd;
6644 pfd.include_nondeduced_p = include_nondeduced_p;
6646 /* Walk the tree. (Conceptually, we would like to walk without
6647 duplicates, but for_each_template_parm_r recursively calls
6648 for_each_template_parm, so we would need to reorganize a fair
6649 bit to use walk_tree_without_duplicates, so we keep our own
6652 pfd.visited = visited;
6654 pfd.visited = pointer_set_create ();
6655 result = cp_walk_tree (&t,
6656 for_each_template_parm_r,
6658 pfd.visited) != NULL_TREE;
6663 pointer_set_destroy (pfd.visited);
6670 /* Returns true if T depends on any template parameter. */
6673 uses_template_parms (tree t)
6676 int saved_processing_template_decl;
6678 saved_processing_template_decl = processing_template_decl;
6679 if (!saved_processing_template_decl)
6680 processing_template_decl = 1;
6682 dependent_p = dependent_type_p (t);
6683 else if (TREE_CODE (t) == TREE_VEC)
6684 dependent_p = any_dependent_template_arguments_p (t);
6685 else if (TREE_CODE (t) == TREE_LIST)
6686 dependent_p = (uses_template_parms (TREE_VALUE (t))
6687 || uses_template_parms (TREE_CHAIN (t)));
6688 else if (TREE_CODE (t) == TYPE_DECL)
6689 dependent_p = dependent_type_p (TREE_TYPE (t));
6692 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
6693 || TREE_CODE (t) == OVERLOAD
6694 || TREE_CODE (t) == BASELINK
6695 || TREE_CODE (t) == IDENTIFIER_NODE
6696 || TREE_CODE (t) == TRAIT_EXPR
6697 || TREE_CODE (t) == CONSTRUCTOR
6698 || CONSTANT_CLASS_P (t))
6699 dependent_p = (type_dependent_expression_p (t)
6700 || value_dependent_expression_p (t));
6703 gcc_assert (t == error_mark_node);
6704 dependent_p = false;
6707 processing_template_decl = saved_processing_template_decl;
6712 /* Returns true if T depends on any template parameter with level LEVEL. */
6715 uses_template_parms_level (tree t, int level)
6717 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
6718 /*include_nondeduced_p=*/true);
6721 static int tinst_depth;
6722 extern int max_tinst_depth;
6723 #ifdef GATHER_STATISTICS
6726 static int tinst_level_tick;
6727 static int last_template_error_tick;
6729 /* We're starting to instantiate D; record the template instantiation context
6730 for diagnostics and to restore it later. */
6733 push_tinst_level (tree d)
6735 struct tinst_level *new_level;
6737 if (tinst_depth >= max_tinst_depth)
6739 /* If the instantiation in question still has unbound template parms,
6740 we don't really care if we can't instantiate it, so just return.
6741 This happens with base instantiation for implicit `typename'. */
6742 if (uses_template_parms (d))
6745 last_template_error_tick = tinst_level_tick;
6746 error ("template instantiation depth exceeds maximum of %d (use "
6747 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
6748 max_tinst_depth, d);
6750 print_instantiation_context ();
6755 new_level = GGC_NEW (struct tinst_level);
6756 new_level->decl = d;
6757 new_level->locus = input_location;
6758 new_level->in_system_header_p = in_system_header;
6759 new_level->next = current_tinst_level;
6760 current_tinst_level = new_level;
6763 #ifdef GATHER_STATISTICS
6764 if (tinst_depth > depth_reached)
6765 depth_reached = tinst_depth;
6772 /* We're done instantiating this template; return to the instantiation
6776 pop_tinst_level (void)
6778 /* Restore the filename and line number stashed away when we started
6779 this instantiation. */
6780 input_location = current_tinst_level->locus;
6781 current_tinst_level = current_tinst_level->next;
6786 /* We're instantiating a deferred template; restore the template
6787 instantiation context in which the instantiation was requested, which
6788 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
6791 reopen_tinst_level (struct tinst_level *level)
6793 struct tinst_level *t;
6796 for (t = level; t; t = t->next)
6799 current_tinst_level = level;
6804 /* Returns the TINST_LEVEL which gives the original instantiation
6807 struct tinst_level *
6808 outermost_tinst_level (void)
6810 struct tinst_level *level = current_tinst_level;
6813 level = level->next;
6817 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
6820 parameter_of_template_p (tree parm, tree templ)
6825 if (!parm || !templ)
6828 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
6829 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
6831 parms = DECL_TEMPLATE_PARMS (templ);
6832 parms = INNERMOST_TEMPLATE_PARMS (parms);
6834 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
6835 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
6841 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
6842 vector of template arguments, as for tsubst.
6844 Returns an appropriate tsubst'd friend declaration. */
6847 tsubst_friend_function (tree decl, tree args)
6851 if (TREE_CODE (decl) == FUNCTION_DECL
6852 && DECL_TEMPLATE_INSTANTIATION (decl)
6853 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
6854 /* This was a friend declared with an explicit template
6855 argument list, e.g.:
6859 to indicate that f was a template instantiation, not a new
6860 function declaration. Now, we have to figure out what
6861 instantiation of what template. */
6863 tree template_id, arglist, fns;
6866 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
6868 /* Friend functions are looked up in the containing namespace scope.
6869 We must enter that scope, to avoid finding member functions of the
6870 current class with same name. */
6871 push_nested_namespace (ns);
6872 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
6873 tf_warning_or_error, NULL_TREE,
6874 /*integral_constant_expression_p=*/false);
6875 pop_nested_namespace (ns);
6876 arglist = tsubst (DECL_TI_ARGS (decl), args,
6877 tf_warning_or_error, NULL_TREE);
6878 template_id = lookup_template_function (fns, arglist);
6880 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6881 tmpl = determine_specialization (template_id, new_friend,
6883 /*need_member_template=*/0,
6884 TREE_VEC_LENGTH (args),
6886 return instantiate_template (tmpl, new_args, tf_error);
6889 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6891 /* The NEW_FRIEND will look like an instantiation, to the
6892 compiler, but is not an instantiation from the point of view of
6893 the language. For example, we might have had:
6895 template <class T> struct S {
6896 template <class U> friend void f(T, U);
6899 Then, in S<int>, template <class U> void f(int, U) is not an
6900 instantiation of anything. */
6901 if (new_friend == error_mark_node)
6902 return error_mark_node;
6904 DECL_USE_TEMPLATE (new_friend) = 0;
6905 if (TREE_CODE (decl) == TEMPLATE_DECL)
6907 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
6908 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
6909 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
6912 /* The mangled name for the NEW_FRIEND is incorrect. The function
6913 is not a template instantiation and should not be mangled like
6914 one. Therefore, we forget the mangling here; we'll recompute it
6915 later if we need it. */
6916 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
6918 SET_DECL_RTL (new_friend, NULL_RTX);
6919 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
6922 if (DECL_NAMESPACE_SCOPE_P (new_friend))
6925 tree new_friend_template_info;
6926 tree new_friend_result_template_info;
6928 int new_friend_is_defn;
6930 /* We must save some information from NEW_FRIEND before calling
6931 duplicate decls since that function will free NEW_FRIEND if
6933 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
6934 new_friend_is_defn =
6935 (DECL_INITIAL (DECL_TEMPLATE_RESULT
6936 (template_for_substitution (new_friend)))
6938 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
6940 /* This declaration is a `primary' template. */
6941 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
6943 new_friend_result_template_info
6944 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
6947 new_friend_result_template_info = NULL_TREE;
6949 /* Make the init_value nonzero so pushdecl knows this is a defn. */
6950 if (new_friend_is_defn)
6951 DECL_INITIAL (new_friend) = error_mark_node;
6953 /* Inside pushdecl_namespace_level, we will push into the
6954 current namespace. However, the friend function should go
6955 into the namespace of the template. */
6956 ns = decl_namespace_context (new_friend);
6957 push_nested_namespace (ns);
6958 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
6959 pop_nested_namespace (ns);
6961 if (old_decl == error_mark_node)
6962 return error_mark_node;
6964 if (old_decl != new_friend)
6966 /* This new friend declaration matched an existing
6967 declaration. For example, given:
6969 template <class T> void f(T);
6970 template <class U> class C {
6971 template <class T> friend void f(T) {}
6974 the friend declaration actually provides the definition
6975 of `f', once C has been instantiated for some type. So,
6976 old_decl will be the out-of-class template declaration,
6977 while new_friend is the in-class definition.
6979 But, if `f' was called before this point, the
6980 instantiation of `f' will have DECL_TI_ARGS corresponding
6981 to `T' but not to `U', references to which might appear
6982 in the definition of `f'. Previously, the most general
6983 template for an instantiation of `f' was the out-of-class
6984 version; now it is the in-class version. Therefore, we
6985 run through all specialization of `f', adding to their
6986 DECL_TI_ARGS appropriately. In particular, they need a
6987 new set of outer arguments, corresponding to the
6988 arguments for this class instantiation.
6990 The same situation can arise with something like this:
6993 template <class T> class C {
6997 when `C<int>' is instantiated. Now, `f(int)' is defined
7000 if (!new_friend_is_defn)
7001 /* On the other hand, if the in-class declaration does
7002 *not* provide a definition, then we don't want to alter
7003 existing definitions. We can just leave everything
7008 tree new_template = TI_TEMPLATE (new_friend_template_info);
7009 tree new_args = TI_ARGS (new_friend_template_info);
7011 /* Overwrite whatever template info was there before, if
7012 any, with the new template information pertaining to
7014 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
7016 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
7017 /* We should have called reregister_specialization in
7019 gcc_assert (retrieve_specialization (new_template,
7026 /* Indicate that the old function template is a partial
7028 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
7029 = new_friend_result_template_info;
7031 gcc_assert (new_template
7032 == most_general_template (new_template));
7033 gcc_assert (new_template != old_decl);
7035 /* Reassign any specializations already in the hash table
7036 to the new more general template, and add the
7037 additional template args. */
7038 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
7042 tree spec = TREE_VALUE (t);
7045 elt.tmpl = old_decl;
7046 elt.args = DECL_TI_ARGS (spec);
7047 elt.spec = NULL_TREE;
7049 htab_remove_elt (decl_specializations, &elt);
7052 = add_outermost_template_args (new_args,
7053 DECL_TI_ARGS (spec));
7055 register_specialization
7056 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
7059 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
7063 /* The information from NEW_FRIEND has been merged into OLD_DECL
7064 by duplicate_decls. */
7065 new_friend = old_decl;
7070 tree context = DECL_CONTEXT (new_friend);
7074 template <class T> class C {
7075 template <class U> friend void C1<U>::f (); // case 1
7076 friend void C2<T>::f (); // case 2
7078 we only need to make sure CONTEXT is a complete type for
7079 case 2. To distinguish between the two cases, we note that
7080 CONTEXT of case 1 remains dependent type after tsubst while
7081 this isn't true for case 2. */
7082 ++processing_template_decl;
7083 dependent_p = dependent_type_p (context);
7084 --processing_template_decl;
7087 && !complete_type_or_else (context, NULL_TREE))
7088 return error_mark_node;
7090 if (COMPLETE_TYPE_P (context))
7092 /* Check to see that the declaration is really present, and,
7093 possibly obtain an improved declaration. */
7094 tree fn = check_classfn (context,
7095 new_friend, NULL_TREE);
7105 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
7106 template arguments, as for tsubst.
7108 Returns an appropriate tsubst'd friend type or error_mark_node on
7112 tsubst_friend_class (tree friend_tmpl, tree args)
7118 context = DECL_CONTEXT (friend_tmpl);
7122 if (TREE_CODE (context) == NAMESPACE_DECL)
7123 push_nested_namespace (context);
7125 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
7128 /* Look for a class template declaration. We look for hidden names
7129 because two friend declarations of the same template are the
7130 same. For example, in:
7133 template <typename> friend class F;
7135 template <typename> struct B {
7136 template <typename> friend class F;
7139 both F templates are the same. */
7140 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
7141 /*block_p=*/true, 0,
7142 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
7144 /* But, if we don't find one, it might be because we're in a
7145 situation like this:
7153 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
7154 for `S<int>', not the TEMPLATE_DECL. */
7155 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
7157 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
7158 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
7161 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
7163 /* The friend template has already been declared. Just
7164 check to see that the declarations match, and install any new
7165 default parameters. We must tsubst the default parameters,
7166 of course. We only need the innermost template parameters
7167 because that is all that redeclare_class_template will look
7169 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
7170 > TMPL_ARGS_DEPTH (args))
7173 location_t saved_input_location;
7174 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
7175 args, tf_warning_or_error);
7177 saved_input_location = input_location;
7178 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
7179 redeclare_class_template (TREE_TYPE (tmpl), parms);
7180 input_location = saved_input_location;
7184 friend_type = TREE_TYPE (tmpl);
7188 /* The friend template has not already been declared. In this
7189 case, the instantiation of the template class will cause the
7190 injection of this template into the global scope. */
7191 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7192 if (tmpl == error_mark_node)
7193 return error_mark_node;
7195 /* The new TMPL is not an instantiation of anything, so we
7196 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7197 the new type because that is supposed to be the corresponding
7198 template decl, i.e., TMPL. */
7199 DECL_USE_TEMPLATE (tmpl) = 0;
7200 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7201 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7202 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7203 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7205 /* Inject this template into the global scope. */
7206 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7211 if (TREE_CODE (context) == NAMESPACE_DECL)
7212 pop_nested_namespace (context);
7214 pop_nested_class ();
7220 /* Returns zero if TYPE cannot be completed later due to circularity.
7221 Otherwise returns one. */
7224 can_complete_type_without_circularity (tree type)
7226 if (type == NULL_TREE || type == error_mark_node)
7228 else if (COMPLETE_TYPE_P (type))
7230 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7231 return can_complete_type_without_circularity (TREE_TYPE (type));
7232 else if (CLASS_TYPE_P (type)
7233 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
7239 /* Apply any attributes which had to be deferred until instantiation
7240 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
7241 ARGS, COMPLAIN, IN_DECL are as tsubst. */
7244 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
7245 tree args, tsubst_flags_t complain, tree in_decl)
7247 tree last_dep = NULL_TREE;
7251 for (t = attributes; t; t = TREE_CHAIN (t))
7252 if (ATTR_IS_DEPENDENT (t))
7255 attributes = copy_list (attributes);
7259 if (DECL_P (*decl_p))
7261 if (TREE_TYPE (*decl_p) == error_mark_node)
7263 p = &DECL_ATTRIBUTES (*decl_p);
7266 p = &TYPE_ATTRIBUTES (*decl_p);
7270 tree late_attrs = NULL_TREE;
7271 tree *q = &late_attrs;
7273 for (*p = attributes; *p; )
7276 if (ATTR_IS_DEPENDENT (t))
7278 *p = TREE_CHAIN (t);
7279 TREE_CHAIN (t) = NULL_TREE;
7280 /* If the first attribute argument is an identifier, don't
7281 pass it through tsubst. Attributes like mode, format,
7282 cleanup and several target specific attributes expect it
7285 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
7286 && TREE_VALUE (TREE_VALUE (t))
7287 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
7288 == IDENTIFIER_NODE))
7291 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
7293 /*integral_constant_expression_p=*/false);
7294 if (chain != TREE_CHAIN (TREE_VALUE (t)))
7296 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
7301 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
7302 /*integral_constant_expression_p=*/false);
7304 q = &TREE_CHAIN (t);
7307 p = &TREE_CHAIN (t);
7310 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
7314 /* Perform (or defer) access check for typedefs that were referenced
7315 from within the template TMPL code.
7316 This is a subroutine of instantiate_template and instantiate_class_template.
7317 TMPL is the template to consider and TARGS is the list of arguments of
7321 perform_typedefs_access_check (tree tmpl, tree targs)
7326 || (!CLASS_TYPE_P (tmpl)
7327 && TREE_CODE (tmpl) != FUNCTION_DECL))
7330 for (t = get_types_needing_access_check (tmpl); t; t = TREE_CHAIN (t))
7332 tree type_decl = TREE_PURPOSE (t);
7333 tree type_scope = TREE_VALUE (t);
7335 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
7338 if (uses_template_parms (type_decl))
7339 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
7340 if (uses_template_parms (type_scope))
7341 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
7343 perform_or_defer_access_check (TYPE_BINFO (type_scope),
7344 type_decl, type_decl);
7349 instantiate_class_template (tree type)
7351 tree templ, args, pattern, t, member;
7355 unsigned int saved_maximum_field_alignment;
7357 if (type == error_mark_node)
7358 return error_mark_node;
7360 if (TYPE_BEING_DEFINED (type)
7361 || COMPLETE_TYPE_P (type)
7362 || uses_template_parms (type))
7365 /* Figure out which template is being instantiated. */
7366 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
7367 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7369 /* Determine what specialization of the original template to
7371 t = most_specialized_class (type, templ);
7372 if (t == error_mark_node)
7374 TYPE_BEING_DEFINED (type) = 1;
7375 return error_mark_node;
7379 /* This TYPE is actually an instantiation of a partial
7380 specialization. We replace the innermost set of ARGS with
7381 the arguments appropriate for substitution. For example,
7384 template <class T> struct S {};
7385 template <class T> struct S<T*> {};
7387 and supposing that we are instantiating S<int*>, ARGS will
7388 presently be {int*} -- but we need {int}. */
7389 pattern = TREE_TYPE (t);
7390 args = TREE_PURPOSE (t);
7394 pattern = TREE_TYPE (templ);
7395 args = CLASSTYPE_TI_ARGS (type);
7398 /* If the template we're instantiating is incomplete, then clearly
7399 there's nothing we can do. */
7400 if (!COMPLETE_TYPE_P (pattern))
7403 /* If we've recursively instantiated too many templates, stop. */
7404 if (! push_tinst_level (type))
7407 /* Now we're really doing the instantiation. Mark the type as in
7408 the process of being defined. */
7409 TYPE_BEING_DEFINED (type) = 1;
7411 /* We may be in the middle of deferred access check. Disable
7413 push_deferring_access_checks (dk_no_deferred);
7415 push_to_top_level ();
7416 /* Use #pragma pack from the template context. */
7417 saved_maximum_field_alignment = maximum_field_alignment;
7418 maximum_field_alignment = TYPE_PRECISION (pattern);
7420 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
7422 /* Set the input location to the most specialized template definition.
7423 This is needed if tsubsting causes an error. */
7424 typedecl = TYPE_MAIN_DECL (pattern);
7425 input_location = DECL_SOURCE_LOCATION (typedecl);
7427 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
7428 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
7429 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
7430 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
7431 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
7432 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
7433 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
7434 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
7435 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
7436 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
7437 TYPE_PACKED (type) = TYPE_PACKED (pattern);
7438 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
7439 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
7440 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
7441 if (ANON_AGGR_TYPE_P (pattern))
7442 SET_ANON_AGGR_TYPE_P (type);
7443 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
7445 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
7446 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
7449 pbinfo = TYPE_BINFO (pattern);
7451 /* We should never instantiate a nested class before its enclosing
7452 class; we need to look up the nested class by name before we can
7453 instantiate it, and that lookup should instantiate the enclosing
7455 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
7456 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
7457 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
7459 base_list = NULL_TREE;
7460 if (BINFO_N_BASE_BINFOS (pbinfo))
7463 tree context = TYPE_CONTEXT (type);
7467 /* We must enter the scope containing the type, as that is where
7468 the accessibility of types named in dependent bases are
7470 pushed_scope = push_scope (context ? context : global_namespace);
7472 /* Substitute into each of the bases to determine the actual
7474 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
7477 tree access = BINFO_BASE_ACCESS (pbinfo, i);
7478 tree expanded_bases = NULL_TREE;
7481 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
7484 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
7485 args, tf_error, NULL_TREE);
7486 if (expanded_bases == error_mark_node)
7489 len = TREE_VEC_LENGTH (expanded_bases);
7492 for (idx = 0; idx < len; idx++)
7495 /* Extract the already-expanded base class. */
7496 base = TREE_VEC_ELT (expanded_bases, idx);
7498 /* Substitute to figure out the base class. */
7499 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
7502 if (base == error_mark_node)
7505 base_list = tree_cons (access, base, base_list);
7506 if (BINFO_VIRTUAL_P (pbase_binfo))
7507 TREE_TYPE (base_list) = integer_type_node;
7511 /* The list is now in reverse order; correct that. */
7512 base_list = nreverse (base_list);
7515 pop_scope (pushed_scope);
7517 /* Now call xref_basetypes to set up all the base-class
7519 xref_basetypes (type, base_list);
7521 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
7522 (int) ATTR_FLAG_TYPE_IN_PLACE,
7523 args, tf_error, NULL_TREE);
7525 /* Now that our base classes are set up, enter the scope of the
7526 class, so that name lookups into base classes, etc. will work
7527 correctly. This is precisely analogous to what we do in
7528 begin_class_definition when defining an ordinary non-template
7529 class, except we also need to push the enclosing classes. */
7530 push_nested_class (type);
7532 /* Now members are processed in the order of declaration. */
7533 for (member = CLASSTYPE_DECL_LIST (pattern);
7534 member; member = TREE_CHAIN (member))
7536 tree t = TREE_VALUE (member);
7538 if (TREE_PURPOSE (member))
7542 /* Build new CLASSTYPE_NESTED_UTDS. */
7545 bool class_template_p;
7547 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
7548 && TYPE_LANG_SPECIFIC (t)
7549 && CLASSTYPE_IS_TEMPLATE (t));
7550 /* If the member is a class template, then -- even after
7551 substitution -- there may be dependent types in the
7552 template argument list for the class. We increment
7553 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
7554 that function will assume that no types are dependent
7555 when outside of a template. */
7556 if (class_template_p)
7557 ++processing_template_decl;
7558 newtag = tsubst (t, args, tf_error, NULL_TREE);
7559 if (class_template_p)
7560 --processing_template_decl;
7561 if (newtag == error_mark_node)
7564 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
7566 tree name = TYPE_IDENTIFIER (t);
7568 if (class_template_p)
7569 /* Unfortunately, lookup_template_class sets
7570 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
7571 instantiation (i.e., for the type of a member
7572 template class nested within a template class.)
7573 This behavior is required for
7574 maybe_process_partial_specialization to work
7575 correctly, but is not accurate in this case;
7576 the TAG is not an instantiation of anything.
7577 (The corresponding TEMPLATE_DECL is an
7578 instantiation, but the TYPE is not.) */
7579 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
7581 /* Now, we call pushtag to put this NEWTAG into the scope of
7582 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
7583 pushtag calling push_template_decl. We don't have to do
7584 this for enums because it will already have been done in
7587 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
7588 pushtag (name, newtag, /*tag_scope=*/ts_current);
7591 else if (TREE_CODE (t) == FUNCTION_DECL
7592 || DECL_FUNCTION_TEMPLATE_P (t))
7594 /* Build new TYPE_METHODS. */
7597 if (TREE_CODE (t) == TEMPLATE_DECL)
7598 ++processing_template_decl;
7599 r = tsubst (t, args, tf_error, NULL_TREE);
7600 if (TREE_CODE (t) == TEMPLATE_DECL)
7601 --processing_template_decl;
7602 set_current_access_from_decl (r);
7603 finish_member_declaration (r);
7607 /* Build new TYPE_FIELDS. */
7608 if (TREE_CODE (t) == STATIC_ASSERT)
7611 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
7612 tf_warning_or_error, NULL_TREE,
7613 /*integral_constant_expression_p=*/true);
7614 finish_static_assert (condition,
7615 STATIC_ASSERT_MESSAGE (t),
7616 STATIC_ASSERT_SOURCE_LOCATION (t),
7619 else if (TREE_CODE (t) != CONST_DECL)
7623 /* The file and line for this declaration, to
7624 assist in error message reporting. Since we
7625 called push_tinst_level above, we don't need to
7627 input_location = DECL_SOURCE_LOCATION (t);
7629 if (TREE_CODE (t) == TEMPLATE_DECL)
7630 ++processing_template_decl;
7631 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
7632 if (TREE_CODE (t) == TEMPLATE_DECL)
7633 --processing_template_decl;
7634 if (TREE_CODE (r) == VAR_DECL)
7638 [t]he initialization (and any associated
7639 side-effects) of a static data member does
7640 not occur unless the static data member is
7641 itself used in a way that requires the
7642 definition of the static data member to
7645 Therefore, we do not substitute into the
7646 initialized for the static data member here. */
7647 finish_static_data_member_decl
7650 /*init_const_expr_p=*/false,
7651 /*asmspec_tree=*/NULL_TREE,
7653 if (DECL_INITIALIZED_IN_CLASS_P (r))
7654 check_static_variable_definition (r, TREE_TYPE (r));
7656 else if (TREE_CODE (r) == FIELD_DECL)
7658 /* Determine whether R has a valid type and can be
7659 completed later. If R is invalid, then it is
7660 replaced by error_mark_node so that it will not be
7661 added to TYPE_FIELDS. */
7662 tree rtype = TREE_TYPE (r);
7663 if (can_complete_type_without_circularity (rtype))
7664 complete_type (rtype);
7666 if (!COMPLETE_TYPE_P (rtype))
7668 cxx_incomplete_type_error (r, rtype);
7669 r = error_mark_node;
7673 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
7674 such a thing will already have been added to the field
7675 list by tsubst_enum in finish_member_declaration in the
7676 CLASSTYPE_NESTED_UTDS case above. */
7677 if (!(TREE_CODE (r) == TYPE_DECL
7678 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
7679 && DECL_ARTIFICIAL (r)))
7681 set_current_access_from_decl (r);
7682 finish_member_declaration (r);
7689 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
7691 /* Build new CLASSTYPE_FRIEND_CLASSES. */
7693 tree friend_type = t;
7694 bool adjust_processing_template_decl = false;
7696 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7698 /* template <class T> friend class C; */
7699 friend_type = tsubst_friend_class (friend_type, args);
7700 adjust_processing_template_decl = true;
7702 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
7704 /* template <class T> friend class C::D; */
7705 friend_type = tsubst (friend_type, args,
7706 tf_warning_or_error, NULL_TREE);
7707 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7708 friend_type = TREE_TYPE (friend_type);
7709 adjust_processing_template_decl = true;
7711 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
7713 /* This could be either
7717 when dependent_type_p is false or
7719 template <class U> friend class T::C;
7722 friend_type = tsubst (friend_type, args,
7723 tf_warning_or_error, NULL_TREE);
7724 /* Bump processing_template_decl for correct
7725 dependent_type_p calculation. */
7726 ++processing_template_decl;
7727 if (dependent_type_p (friend_type))
7728 adjust_processing_template_decl = true;
7729 --processing_template_decl;
7731 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
7732 && hidden_name_p (TYPE_NAME (friend_type)))
7736 where C hasn't been declared yet. Let's lookup name
7737 from namespace scope directly, bypassing any name that
7738 come from dependent base class. */
7739 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
7741 /* The call to xref_tag_from_type does injection for friend
7743 push_nested_namespace (ns);
7745 xref_tag_from_type (friend_type, NULL_TREE,
7746 /*tag_scope=*/ts_current);
7747 pop_nested_namespace (ns);
7749 else if (uses_template_parms (friend_type))
7750 /* friend class C<T>; */
7751 friend_type = tsubst (friend_type, args,
7752 tf_warning_or_error, NULL_TREE);
7757 where C is already declared or
7759 friend class C<int>;
7761 We don't have to do anything in these cases. */
7763 if (adjust_processing_template_decl)
7764 /* Trick make_friend_class into realizing that the friend
7765 we're adding is a template, not an ordinary class. It's
7766 important that we use make_friend_class since it will
7767 perform some error-checking and output cross-reference
7769 ++processing_template_decl;
7771 if (friend_type != error_mark_node)
7772 make_friend_class (type, friend_type, /*complain=*/false);
7774 if (adjust_processing_template_decl)
7775 --processing_template_decl;
7779 /* Build new DECL_FRIENDLIST. */
7782 /* The file and line for this declaration, to
7783 assist in error message reporting. Since we
7784 called push_tinst_level above, we don't need to
7786 input_location = DECL_SOURCE_LOCATION (t);
7788 if (TREE_CODE (t) == TEMPLATE_DECL)
7790 ++processing_template_decl;
7791 push_deferring_access_checks (dk_no_check);
7794 r = tsubst_friend_function (t, args);
7795 add_friend (type, r, /*complain=*/false);
7796 if (TREE_CODE (t) == TEMPLATE_DECL)
7798 pop_deferring_access_checks ();
7799 --processing_template_decl;
7805 /* Set the file and line number information to whatever is given for
7806 the class itself. This puts error messages involving generated
7807 implicit functions at a predictable point, and the same point
7808 that would be used for non-template classes. */
7809 input_location = DECL_SOURCE_LOCATION (typedecl);
7811 unreverse_member_declarations (type);
7812 finish_struct_1 (type);
7813 TYPE_BEING_DEFINED (type) = 0;
7815 /* Now that the class is complete, instantiate default arguments for
7816 any member functions. We don't do this earlier because the
7817 default arguments may reference members of the class. */
7818 if (!PRIMARY_TEMPLATE_P (templ))
7819 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
7820 if (TREE_CODE (t) == FUNCTION_DECL
7821 /* Implicitly generated member functions will not have template
7822 information; they are not instantiations, but instead are
7823 created "fresh" for each instantiation. */
7824 && DECL_TEMPLATE_INFO (t))
7825 tsubst_default_arguments (t);
7827 /* Some typedefs referenced from within the template code need to be access
7828 checked at template instantiation time, i.e now. These types were
7829 added to the template at parsing time. Let's get those and perform
7830 the access checks then. */
7831 perform_typedefs_access_check (pattern, args);
7832 perform_deferred_access_checks ();
7833 pop_nested_class ();
7834 maximum_field_alignment = saved_maximum_field_alignment;
7835 pop_from_top_level ();
7836 pop_deferring_access_checks ();
7839 /* The vtable for a template class can be emitted in any translation
7840 unit in which the class is instantiated. When there is no key
7841 method, however, finish_struct_1 will already have added TYPE to
7842 the keyed_classes list. */
7843 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
7844 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
7850 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7856 else if (TYPE_P (t))
7857 r = tsubst (t, args, complain, in_decl);
7860 r = tsubst_expr (t, args, complain, in_decl,
7861 /*integral_constant_expression_p=*/true);
7862 r = fold_non_dependent_expr (r);
7867 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
7868 NONTYPE_ARGUMENT_PACK. */
7871 make_fnparm_pack (tree spec_parm)
7873 /* Collect all of the extra "packed" parameters into an
7877 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
7878 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
7879 int i, len = list_length (spec_parm);
7881 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
7882 parmvec = make_tree_vec (len);
7883 parmtypevec = make_tree_vec (len);
7884 for (i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
7886 TREE_VEC_ELT (parmvec, i) = spec_parm;
7887 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
7890 /* Build the argument packs. */
7891 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
7892 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
7893 TREE_TYPE (argpack) = argtypepack;
7898 /* Substitute ARGS into T, which is an pack expansion
7899 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
7900 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
7901 (if only a partial substitution could be performed) or
7902 ERROR_MARK_NODE if there was an error. */
7904 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
7908 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
7909 tree first_arg_pack; int i, len = -1;
7912 bool very_local_specializations = false;
7914 gcc_assert (PACK_EXPANSION_P (t));
7915 pattern = PACK_EXPANSION_PATTERN (t);
7917 /* Determine the argument packs that will instantiate the parameter
7918 packs used in the expansion expression. While we're at it,
7919 compute the number of arguments to be expanded and make sure it
7921 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
7922 pack = TREE_CHAIN (pack))
7924 tree parm_pack = TREE_VALUE (pack);
7925 tree arg_pack = NULL_TREE;
7926 tree orig_arg = NULL_TREE;
7928 if (TREE_CODE (parm_pack) == PARM_DECL)
7930 arg_pack = retrieve_local_specialization (parm_pack);
7931 if (arg_pack == NULL_TREE)
7933 /* This can happen for a parameter name used later in a function
7934 declaration (such as in a late-specified return type). Just
7935 make a dummy decl, since it's only used for its type. */
7936 gcc_assert (cp_unevaluated_operand != 0);
7937 arg_pack = tsubst_decl (parm_pack, args, complain);
7938 arg_pack = make_fnparm_pack (arg_pack);
7943 int level, idx, levels;
7944 template_parm_level_and_index (parm_pack, &level, &idx);
7946 levels = TMPL_ARGS_DEPTH (args);
7947 if (level <= levels)
7948 arg_pack = TMPL_ARG (args, level, idx);
7951 orig_arg = arg_pack;
7952 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
7953 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
7955 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
7956 /* This can only happen if we forget to expand an argument
7957 pack somewhere else. Just return an error, silently. */
7959 result = make_tree_vec (1);
7960 TREE_VEC_ELT (result, 0) = error_mark_node;
7965 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
7966 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
7968 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
7969 tree pattern = PACK_EXPANSION_PATTERN (expansion);
7970 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
7971 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
7972 /* The argument pack that the parameter maps to is just an
7973 expansion of the parameter itself, such as one would
7974 find in the implicit typedef of a class inside the
7975 class itself. Consider this parameter "unsubstituted",
7976 so that we will maintain the outer pack expansion. */
7977 arg_pack = NULL_TREE;
7983 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
7985 /* It's all-or-nothing with incomplete argument packs. */
7986 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7987 return error_mark_node;
7989 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7995 first_arg_pack = arg_pack;
7997 else if (len != my_len)
8000 /* We got explicit args for some packs but not others;
8001 do nothing now and try again after deduction. */
8003 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
8004 error ("mismatched argument pack lengths while expanding "
8008 error ("mismatched argument pack lengths while expanding "
8011 return error_mark_node;
8014 /* Keep track of the parameter packs and their corresponding
8016 packs = tree_cons (parm_pack, arg_pack, packs);
8017 TREE_TYPE (packs) = orig_arg;
8020 /* We can't substitute for this parameter pack. */
8021 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
8023 unsubstituted_packs);
8026 /* We cannot expand this expansion expression, because we don't have
8027 all of the argument packs we need. Substitute into the pattern
8028 and return a PACK_EXPANSION_*. The caller will need to deal with
8030 if (unsubstituted_packs)
8033 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8034 new_pat = tsubst_expr (pattern, args, complain, in_decl,
8035 /*integral_constant_expression_p=*/false);
8037 new_pat = tsubst (pattern, args, complain, in_decl);
8038 return make_pack_expansion (new_pat);
8041 /* We could not find any argument packs that work. */
8043 return error_mark_node;
8045 if (!local_specializations)
8047 /* We're in a late-specified return type, so we don't have a local
8048 specializations table. Create one for doing this expansion. */
8049 very_local_specializations = true;
8050 local_specializations = htab_create (37,
8051 hash_local_specialization,
8052 eq_local_specializations,
8056 /* For each argument in each argument pack, substitute into the
8058 result = make_tree_vec (len + incomplete);
8059 for (i = 0; i < len + incomplete; ++i)
8061 /* For parameter pack, change the substitution of the parameter
8062 pack to the ith argument in its argument pack, then expand
8064 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8066 tree parm = TREE_PURPOSE (pack);
8068 if (TREE_CODE (parm) == PARM_DECL)
8070 /* Select the Ith argument from the pack. */
8071 tree arg = make_node (ARGUMENT_PACK_SELECT);
8072 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
8073 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
8075 register_local_specialization (arg, parm);
8081 template_parm_level_and_index (parm, &level, &idx);
8085 /* Select the Ith argument from the pack. */
8086 value = make_node (ARGUMENT_PACK_SELECT);
8087 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
8088 ARGUMENT_PACK_SELECT_INDEX (value) = i;
8091 /* Update the corresponding argument. */
8092 TMPL_ARG (args, level, idx) = value;
8096 /* Substitute into the PATTERN with the altered arguments. */
8097 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
8098 TREE_VEC_ELT (result, i) =
8099 tsubst_expr (pattern, args, complain, in_decl,
8100 /*integral_constant_expression_p=*/false);
8102 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
8105 /* When we have incomplete argument packs, the last "expanded"
8106 result is itself a pack expansion, which allows us
8107 to deduce more arguments. */
8108 TREE_VEC_ELT (result, i) =
8109 make_pack_expansion (TREE_VEC_ELT (result, i));
8111 if (TREE_VEC_ELT (result, i) == error_mark_node)
8113 result = error_mark_node;
8118 /* Update ARGS to restore the substitution from parameter packs to
8119 their argument packs. */
8120 for (pack = packs; pack; pack = TREE_CHAIN (pack))
8122 tree parm = TREE_PURPOSE (pack);
8124 if (TREE_CODE (parm) == PARM_DECL)
8125 register_local_specialization (TREE_TYPE (pack), parm);
8129 template_parm_level_and_index (parm, &level, &idx);
8131 /* Update the corresponding argument. */
8132 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
8133 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
8136 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
8140 if (very_local_specializations)
8142 htab_delete (local_specializations);
8143 local_specializations = NULL;
8149 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
8150 TMPL. We do this using DECL_PARM_INDEX, which should work even with
8151 parameter packs; all parms generated from a function parameter pack will
8152 have the same DECL_PARM_INDEX. */
8155 get_pattern_parm (tree parm, tree tmpl)
8157 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
8160 if (DECL_ARTIFICIAL (parm))
8162 for (patparm = DECL_ARGUMENTS (pattern);
8163 patparm; patparm = TREE_CHAIN (patparm))
8164 if (DECL_ARTIFICIAL (patparm)
8165 && DECL_NAME (parm) == DECL_NAME (patparm))
8170 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
8171 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
8172 gcc_assert (DECL_PARM_INDEX (patparm)
8173 == DECL_PARM_INDEX (parm));
8179 /* Substitute ARGS into the vector or list of template arguments T. */
8182 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8185 int len = TREE_VEC_LENGTH (t);
8186 int need_new = 0, i, expanded_len_adjust = 0, out;
8187 tree *elts = (tree *) alloca (len * sizeof (tree));
8189 for (i = 0; i < len; i++)
8191 tree orig_arg = TREE_VEC_ELT (t, i);
8194 if (TREE_CODE (orig_arg) == TREE_VEC)
8195 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
8196 else if (PACK_EXPANSION_P (orig_arg))
8198 /* Substitute into an expansion expression. */
8199 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
8201 if (TREE_CODE (new_arg) == TREE_VEC)
8202 /* Add to the expanded length adjustment the number of
8203 expanded arguments. We subtract one from this
8204 measurement, because the argument pack expression
8205 itself is already counted as 1 in
8206 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
8207 the argument pack is empty. */
8208 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
8210 else if (ARGUMENT_PACK_P (orig_arg))
8212 /* Substitute into each of the arguments. */
8213 new_arg = TYPE_P (orig_arg)
8214 ? cxx_make_type (TREE_CODE (orig_arg))
8215 : make_node (TREE_CODE (orig_arg));
8217 SET_ARGUMENT_PACK_ARGS (
8219 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
8220 args, complain, in_decl));
8222 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
8223 new_arg = error_mark_node;
8225 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
8226 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
8228 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
8230 if (TREE_TYPE (new_arg) == error_mark_node)
8231 new_arg = error_mark_node;
8235 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
8237 if (new_arg == error_mark_node)
8238 return error_mark_node;
8241 if (new_arg != orig_arg)
8248 /* Make space for the expanded arguments coming from template
8250 t = make_tree_vec (len + expanded_len_adjust);
8251 for (i = 0, out = 0; i < len; i++)
8253 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
8254 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
8255 && TREE_CODE (elts[i]) == TREE_VEC)
8259 /* Now expand the template argument pack "in place". */
8260 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
8261 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
8265 TREE_VEC_ELT (t, out) = elts[i];
8273 /* Return the result of substituting ARGS into the template parameters
8274 given by PARMS. If there are m levels of ARGS and m + n levels of
8275 PARMS, then the result will contain n levels of PARMS. For
8276 example, if PARMS is `template <class T> template <class U>
8277 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
8278 result will be `template <int*, double, class V>'. */
8281 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
8286 /* When substituting into a template, we must set
8287 PROCESSING_TEMPLATE_DECL as the template parameters may be
8288 dependent if they are based on one-another, and the dependency
8289 predicates are short-circuit outside of templates. */
8290 ++processing_template_decl;
8292 for (new_parms = &r;
8293 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
8294 new_parms = &(TREE_CHAIN (*new_parms)),
8295 parms = TREE_CHAIN (parms))
8298 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
8301 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
8307 if (parms == error_mark_node)
8310 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
8312 if (tuple == error_mark_node)
8315 default_value = TREE_PURPOSE (tuple);
8316 parm_decl = TREE_VALUE (tuple);
8318 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
8319 if (TREE_CODE (parm_decl) == PARM_DECL
8320 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
8321 parm_decl = error_mark_node;
8322 default_value = tsubst_template_arg (default_value, args,
8323 complain, NULL_TREE);
8325 tuple = build_tree_list (default_value, parm_decl);
8326 TREE_VEC_ELT (new_vec, i) = tuple;
8330 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
8331 - TMPL_ARGS_DEPTH (args)),
8332 new_vec, NULL_TREE);
8335 --processing_template_decl;
8340 /* Substitute the ARGS into the indicated aggregate (or enumeration)
8341 type T. If T is not an aggregate or enumeration type, it is
8342 handled as if by tsubst. IN_DECL is as for tsubst. If
8343 ENTERING_SCOPE is nonzero, T is the context for a template which
8344 we are presently tsubst'ing. Return the substituted value. */
8347 tsubst_aggr_type (tree t,
8349 tsubst_flags_t complain,
8356 switch (TREE_CODE (t))
8359 if (TYPE_PTRMEMFUNC_P (t))
8360 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
8362 /* Else fall through. */
8365 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
8370 int saved_unevaluated_operand;
8371 int saved_inhibit_evaluation_warnings;
8373 /* In "sizeof(X<I>)" we need to evaluate "I". */
8374 saved_unevaluated_operand = cp_unevaluated_operand;
8375 cp_unevaluated_operand = 0;
8376 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
8377 c_inhibit_evaluation_warnings = 0;
8379 /* First, determine the context for the type we are looking
8381 context = TYPE_CONTEXT (t);
8384 context = tsubst_aggr_type (context, args, complain,
8385 in_decl, /*entering_scope=*/1);
8386 /* If context is a nested class inside a class template,
8387 it may still need to be instantiated (c++/33959). */
8388 if (TYPE_P (context))
8389 context = complete_type (context);
8392 /* Then, figure out what arguments are appropriate for the
8393 type we are trying to find. For example, given:
8395 template <class T> struct S;
8396 template <class T, class U> void f(T, U) { S<U> su; }
8398 and supposing that we are instantiating f<int, double>,
8399 then our ARGS will be {int, double}, but, when looking up
8400 S we only want {double}. */
8401 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
8403 if (argvec == error_mark_node)
8404 r = error_mark_node;
8407 r = lookup_template_class (t, argvec, in_decl, context,
8408 entering_scope, complain);
8409 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
8412 cp_unevaluated_operand = saved_unevaluated_operand;
8413 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
8418 /* This is not a template type, so there's nothing to do. */
8422 return tsubst (t, args, complain, in_decl);
8426 /* Substitute into the default argument ARG (a default argument for
8427 FN), which has the indicated TYPE. */
8430 tsubst_default_argument (tree fn, tree type, tree arg)
8432 tree saved_class_ptr = NULL_TREE;
8433 tree saved_class_ref = NULL_TREE;
8435 /* This default argument came from a template. Instantiate the
8436 default argument here, not in tsubst. In the case of
8445 we must be careful to do name lookup in the scope of S<T>,
8446 rather than in the current class. */
8447 push_access_scope (fn);
8448 /* The "this" pointer is not valid in a default argument. */
8451 saved_class_ptr = current_class_ptr;
8452 cp_function_chain->x_current_class_ptr = NULL_TREE;
8453 saved_class_ref = current_class_ref;
8454 cp_function_chain->x_current_class_ref = NULL_TREE;
8457 push_deferring_access_checks(dk_no_deferred);
8458 /* The default argument expression may cause implicitly defined
8459 member functions to be synthesized, which will result in garbage
8460 collection. We must treat this situation as if we were within
8461 the body of function so as to avoid collecting live data on the
8464 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
8465 tf_warning_or_error, NULL_TREE,
8466 /*integral_constant_expression_p=*/false);
8468 pop_deferring_access_checks();
8470 /* Restore the "this" pointer. */
8473 cp_function_chain->x_current_class_ptr = saved_class_ptr;
8474 cp_function_chain->x_current_class_ref = saved_class_ref;
8477 /* Make sure the default argument is reasonable. */
8478 arg = check_default_argument (type, arg);
8480 pop_access_scope (fn);
8485 /* Substitute into all the default arguments for FN. */
8488 tsubst_default_arguments (tree fn)
8493 tmpl_args = DECL_TI_ARGS (fn);
8495 /* If this function is not yet instantiated, we certainly don't need
8496 its default arguments. */
8497 if (uses_template_parms (tmpl_args))
8500 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
8502 arg = TREE_CHAIN (arg))
8503 if (TREE_PURPOSE (arg))
8504 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
8506 TREE_PURPOSE (arg));
8509 /* Substitute the ARGS into the T, which is a _DECL. Return the
8510 result of the substitution. Issue error and warning messages under
8511 control of COMPLAIN. */
8514 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
8516 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
8517 location_t saved_loc;
8522 /* Set the filename and linenumber to improve error-reporting. */
8523 saved_loc = input_location;
8524 input_location = DECL_SOURCE_LOCATION (t);
8526 switch (TREE_CODE (t))
8530 /* We can get here when processing a member function template,
8531 member class template, or template template parameter. */
8532 tree decl = DECL_TEMPLATE_RESULT (t);
8537 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
8539 /* Template template parameter is treated here. */
8540 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8541 if (new_type == error_mark_node)
8542 RETURN (error_mark_node);
8545 TREE_CHAIN (r) = NULL_TREE;
8546 TREE_TYPE (r) = new_type;
8547 DECL_TEMPLATE_RESULT (r)
8548 = build_decl (DECL_SOURCE_LOCATION (decl),
8549 TYPE_DECL, DECL_NAME (decl), new_type);
8550 DECL_TEMPLATE_PARMS (r)
8551 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8553 TYPE_NAME (new_type) = r;
8557 /* We might already have an instance of this template.
8558 The ARGS are for the surrounding class type, so the
8559 full args contain the tsubst'd args for the context,
8560 plus the innermost args from the template decl. */
8561 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
8562 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
8563 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
8564 /* Because this is a template, the arguments will still be
8565 dependent, even after substitution. If
8566 PROCESSING_TEMPLATE_DECL is not set, the dependency
8567 predicates will short-circuit. */
8568 ++processing_template_decl;
8569 full_args = tsubst_template_args (tmpl_args, args,
8571 --processing_template_decl;
8572 if (full_args == error_mark_node)
8573 RETURN (error_mark_node);
8575 /* If this is a default template template argument,
8576 tsubst might not have changed anything. */
8577 if (full_args == tmpl_args)
8580 hash = hash_tmpl_and_args (t, full_args);
8581 spec = retrieve_specialization (t, full_args, hash);
8582 if (spec != NULL_TREE)
8588 /* Make a new template decl. It will be similar to the
8589 original, but will record the current template arguments.
8590 We also create a new function declaration, which is just
8591 like the old one, but points to this new template, rather
8592 than the old one. */
8594 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
8595 TREE_CHAIN (r) = NULL_TREE;
8597 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
8599 if (TREE_CODE (decl) == TYPE_DECL)
8602 ++processing_template_decl;
8603 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8604 --processing_template_decl;
8605 if (new_type == error_mark_node)
8606 RETURN (error_mark_node);
8608 TREE_TYPE (r) = new_type;
8609 CLASSTYPE_TI_TEMPLATE (new_type) = r;
8610 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
8611 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
8612 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
8617 ++processing_template_decl;
8618 new_decl = tsubst (decl, args, complain, in_decl);
8619 --processing_template_decl;
8620 if (new_decl == error_mark_node)
8621 RETURN (error_mark_node);
8623 DECL_TEMPLATE_RESULT (r) = new_decl;
8624 DECL_TI_TEMPLATE (new_decl) = r;
8625 TREE_TYPE (r) = TREE_TYPE (new_decl);
8626 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
8627 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
8630 SET_DECL_IMPLICIT_INSTANTIATION (r);
8631 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
8632 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
8634 /* The template parameters for this new template are all the
8635 template parameters for the old template, except the
8636 outermost level of parameters. */
8637 DECL_TEMPLATE_PARMS (r)
8638 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8641 if (PRIMARY_TEMPLATE_P (t))
8642 DECL_PRIMARY_TEMPLATE (r) = r;
8644 if (TREE_CODE (decl) != TYPE_DECL)
8645 /* Record this non-type partial instantiation. */
8646 register_specialization (r, t,
8647 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
8655 tree argvec = NULL_TREE;
8663 /* Nobody should be tsubst'ing into non-template functions. */
8664 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
8666 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
8671 /* If T is not dependent, just return it. We have to
8672 increment PROCESSING_TEMPLATE_DECL because
8673 value_dependent_expression_p assumes that nothing is
8674 dependent when PROCESSING_TEMPLATE_DECL is zero. */
8675 ++processing_template_decl;
8676 dependent_p = value_dependent_expression_p (t);
8677 --processing_template_decl;
8681 /* Calculate the most general template of which R is a
8682 specialization, and the complete set of arguments used to
8684 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
8685 argvec = tsubst_template_args (DECL_TI_ARGS
8686 (DECL_TEMPLATE_RESULT (gen_tmpl)),
8687 args, complain, in_decl);
8689 /* Check to see if we already have this specialization. */
8690 hash = hash_tmpl_and_args (gen_tmpl, argvec);
8691 spec = retrieve_specialization (gen_tmpl, argvec, hash);
8699 /* We can see more levels of arguments than parameters if
8700 there was a specialization of a member template, like
8703 template <class T> struct S { template <class U> void f(); }
8704 template <> template <class U> void S<int>::f(U);
8706 Here, we'll be substituting into the specialization,
8707 because that's where we can find the code we actually
8708 want to generate, but we'll have enough arguments for
8709 the most general template.
8711 We also deal with the peculiar case:
8713 template <class T> struct S {
8714 template <class U> friend void f();
8716 template <class U> void f() {}
8718 template void f<double>();
8720 Here, the ARGS for the instantiation of will be {int,
8721 double}. But, we only need as many ARGS as there are
8722 levels of template parameters in CODE_PATTERN. We are
8723 careful not to get fooled into reducing the ARGS in
8726 template <class T> struct S { template <class U> void f(U); }
8727 template <class T> template <> void S<T>::f(int) {}
8729 which we can spot because the pattern will be a
8730 specialization in this case. */
8731 args_depth = TMPL_ARGS_DEPTH (args);
8733 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
8734 if (args_depth > parms_depth
8735 && !DECL_TEMPLATE_SPECIALIZATION (t))
8736 args = get_innermost_template_args (args, parms_depth);
8740 /* This special case arises when we have something like this:
8742 template <class T> struct S {
8743 friend void f<int>(int, double);
8746 Here, the DECL_TI_TEMPLATE for the friend declaration
8747 will be an IDENTIFIER_NODE. We are being called from
8748 tsubst_friend_function, and we want only to create a
8749 new decl (R) with appropriate types so that we can call
8750 determine_specialization. */
8751 gen_tmpl = NULL_TREE;
8754 if (DECL_CLASS_SCOPE_P (t))
8756 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
8760 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
8761 complain, t, /*entering_scope=*/1);
8766 ctx = DECL_CONTEXT (t);
8768 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8769 if (type == error_mark_node)
8770 RETURN (error_mark_node);
8772 /* We do NOT check for matching decls pushed separately at this
8773 point, as they may not represent instantiations of this
8774 template, and in any case are considered separate under the
8777 DECL_USE_TEMPLATE (r) = 0;
8778 TREE_TYPE (r) = type;
8779 /* Clear out the mangled name and RTL for the instantiation. */
8780 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8781 SET_DECL_RTL (r, NULL_RTX);
8782 /* Leave DECL_INITIAL set on deleted instantiations. */
8783 if (!DECL_DELETED_FN (r))
8784 DECL_INITIAL (r) = NULL_TREE;
8785 DECL_CONTEXT (r) = ctx;
8787 if (member && DECL_CONV_FN_P (r))
8788 /* Type-conversion operator. Reconstruct the name, in
8789 case it's the name of one of the template's parameters. */
8790 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
8792 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
8794 DECL_RESULT (r) = NULL_TREE;
8796 TREE_STATIC (r) = 0;
8797 TREE_PUBLIC (r) = TREE_PUBLIC (t);
8798 DECL_EXTERNAL (r) = 1;
8799 /* If this is an instantiation of a function with internal
8800 linkage, we already know what object file linkage will be
8801 assigned to the instantiation. */
8802 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
8803 DECL_DEFER_OUTPUT (r) = 0;
8804 TREE_CHAIN (r) = NULL_TREE;
8805 DECL_PENDING_INLINE_INFO (r) = 0;
8806 DECL_PENDING_INLINE_P (r) = 0;
8807 DECL_SAVED_TREE (r) = NULL_TREE;
8808 DECL_STRUCT_FUNCTION (r) = NULL;
8810 /* We'll re-clone as appropriate in instantiate_template. */
8811 DECL_CLONED_FUNCTION (r) = NULL_TREE;
8813 /* If we aren't complaining now, return on error before we register
8814 the specialization so that we'll complain eventually. */
8815 if ((complain & tf_error) == 0
8816 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
8817 && !grok_op_properties (r, /*complain=*/false))
8818 RETURN (error_mark_node);
8820 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
8821 this in the special friend case mentioned above where
8822 GEN_TMPL is NULL. */
8825 DECL_TEMPLATE_INFO (r)
8826 = tree_cons (gen_tmpl, argvec, NULL_TREE);
8827 SET_DECL_IMPLICIT_INSTANTIATION (r);
8828 register_specialization (r, gen_tmpl, argvec, false, hash);
8830 /* We're not supposed to instantiate default arguments
8831 until they are called, for a template. But, for a
8834 template <class T> void f ()
8835 { extern void g(int i = T()); }
8837 we should do the substitution when the template is
8838 instantiated. We handle the member function case in
8839 instantiate_class_template since the default arguments
8840 might refer to other members of the class. */
8842 && !PRIMARY_TEMPLATE_P (gen_tmpl)
8843 && !uses_template_parms (argvec))
8844 tsubst_default_arguments (r);
8847 DECL_TEMPLATE_INFO (r) = NULL_TREE;
8849 /* Copy the list of befriending classes. */
8850 for (friends = &DECL_BEFRIENDING_CLASSES (r);
8852 friends = &TREE_CHAIN (*friends))
8854 *friends = copy_node (*friends);
8855 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
8860 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
8862 maybe_retrofit_in_chrg (r);
8863 if (DECL_CONSTRUCTOR_P (r))
8864 grok_ctor_properties (ctx, r);
8865 /* If this is an instantiation of a member template, clone it.
8866 If it isn't, that'll be handled by
8867 clone_constructors_and_destructors. */
8868 if (PRIMARY_TEMPLATE_P (gen_tmpl))
8869 clone_function_decl (r, /*update_method_vec_p=*/0);
8871 else if ((complain & tf_error) != 0
8872 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
8873 && !grok_op_properties (r, /*complain=*/true))
8874 RETURN (error_mark_node);
8876 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
8877 SET_DECL_FRIEND_CONTEXT (r,
8878 tsubst (DECL_FRIEND_CONTEXT (t),
8879 args, complain, in_decl));
8881 /* Possibly limit visibility based on template args. */
8882 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8883 if (DECL_VISIBILITY_SPECIFIED (t))
8885 DECL_VISIBILITY_SPECIFIED (r) = 0;
8887 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8889 determine_visibility (r);
8890 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
8891 && !processing_template_decl)
8892 defaulted_late_check (r);
8894 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8895 args, complain, in_decl);
8901 tree type = NULL_TREE;
8903 tree expanded_types = NULL_TREE;
8904 tree prev_r = NULL_TREE;
8905 tree first_r = NULL_TREE;
8907 if (FUNCTION_PARAMETER_PACK_P (t))
8909 /* If there is a local specialization that isn't a
8910 parameter pack, it means that we're doing a "simple"
8911 substitution from inside tsubst_pack_expansion. Just
8912 return the local specialization (which will be a single
8914 tree spec = retrieve_local_specialization (t);
8916 && TREE_CODE (spec) == PARM_DECL
8917 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
8920 /* Expand the TYPE_PACK_EXPANSION that provides the types for
8921 the parameters in this function parameter pack. */
8922 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
8924 if (TREE_CODE (expanded_types) == TREE_VEC)
8926 len = TREE_VEC_LENGTH (expanded_types);
8928 /* Zero-length parameter packs are boring. Just substitute
8931 RETURN (tsubst (TREE_CHAIN (t), args, complain,
8936 /* All we did was update the type. Make a note of that. */
8937 type = expanded_types;
8938 expanded_types = NULL_TREE;
8942 /* Loop through all of the parameter's we'll build. When T is
8943 a function parameter pack, LEN is the number of expanded
8944 types in EXPANDED_TYPES; otherwise, LEN is 1. */
8946 for (i = 0; i < len; ++i)
8950 if (DECL_TEMPLATE_PARM_P (t))
8951 SET_DECL_TEMPLATE_PARM_P (r);
8953 /* An argument of a function parameter pack is not a parameter
8955 FUNCTION_PARAMETER_PACK_P (r) = false;
8958 /* We're on the Ith parameter of the function parameter
8961 /* Get the Ith type. */
8962 type = TREE_VEC_ELT (expanded_types, i);
8965 /* Rename the parameter to include the index. */
8967 make_ith_pack_parameter_name (DECL_NAME (r), i);
8970 /* We're dealing with a normal parameter. */
8971 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8973 type = type_decays_to (type);
8974 TREE_TYPE (r) = type;
8975 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8977 if (DECL_INITIAL (r))
8979 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
8980 DECL_INITIAL (r) = TREE_TYPE (r);
8982 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
8986 DECL_CONTEXT (r) = NULL_TREE;
8988 if (!DECL_TEMPLATE_PARM_P (r))
8989 DECL_ARG_TYPE (r) = type_passed_as (type);
8991 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8992 args, complain, in_decl);
8994 /* Keep track of the first new parameter we
8995 generate. That's what will be returned to the
9000 /* Build a proper chain of parameters when substituting
9001 into a function parameter pack. */
9003 TREE_CHAIN (prev_r) = r;
9007 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
9008 complain, TREE_CHAIN (t));
9010 /* FIRST_R contains the start of the chain we've built. */
9020 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9021 if (type == error_mark_node)
9022 RETURN (error_mark_node);
9023 TREE_TYPE (r) = type;
9024 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9026 /* DECL_INITIAL gives the number of bits in a bit-field. */
9028 = tsubst_expr (DECL_INITIAL (t), args,
9030 /*integral_constant_expression_p=*/true);
9031 /* We don't have to set DECL_CONTEXT here; it is set by
9032 finish_member_declaration. */
9033 TREE_CHAIN (r) = NULL_TREE;
9034 if (VOID_TYPE_P (type))
9035 error ("instantiation of %q+D as type %qT", r, type);
9037 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
9038 args, complain, in_decl);
9043 /* We reach here only for member using decls. */
9044 if (DECL_DEPENDENT_P (t))
9046 r = do_class_using_decl
9047 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
9048 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
9050 r = error_mark_node;
9053 TREE_PROTECTED (r) = TREE_PROTECTED (t);
9054 TREE_PRIVATE (r) = TREE_PRIVATE (t);
9060 TREE_CHAIN (r) = NULL_TREE;
9067 tree argvec = NULL_TREE;
9068 tree gen_tmpl = NULL_TREE;
9070 tree tmpl = NULL_TREE;
9072 tree type = NULL_TREE;
9075 if (TREE_CODE (t) == TYPE_DECL
9076 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
9078 /* If this is the canonical decl, we don't have to
9079 mess with instantiations, and often we can't (for
9080 typename, template type parms and such). Note that
9081 TYPE_NAME is not correct for the above test if
9082 we've copied the type for a typedef. */
9083 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9084 if (type == error_mark_node)
9085 RETURN (error_mark_node);
9086 r = TYPE_NAME (type);
9090 /* Check to see if we already have the specialization we
9093 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
9095 /* T is a static data member or namespace-scope entity.
9096 We have to substitute into namespace-scope variables
9097 (even though such entities are never templates) because
9100 template <class T> void f() { extern T t; }
9102 where the entity referenced is not known until
9103 instantiation time. */
9105 ctx = DECL_CONTEXT (t);
9106 if (DECL_CLASS_SCOPE_P (t))
9108 ctx = tsubst_aggr_type (ctx, args,
9110 in_decl, /*entering_scope=*/1);
9111 /* If CTX is unchanged, then T is in fact the
9112 specialization we want. That situation occurs when
9113 referencing a static data member within in its own
9114 class. We can use pointer equality, rather than
9115 same_type_p, because DECL_CONTEXT is always
9117 if (ctx == DECL_CONTEXT (t))
9123 tmpl = DECL_TI_TEMPLATE (t);
9124 gen_tmpl = most_general_template (tmpl);
9125 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
9126 hash = hash_tmpl_and_args (gen_tmpl, argvec);
9127 spec = retrieve_specialization (gen_tmpl, argvec, hash);
9132 /* A local variable. */
9134 /* Subsequent calls to pushdecl will fill this in. */
9136 spec = retrieve_local_specialization (t);
9138 /* If we already have the specialization we need, there is
9139 nothing more to do. */
9146 /* Create a new node for the specialization we need. */
9148 if (type == NULL_TREE)
9149 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9150 if (TREE_CODE (r) == VAR_DECL)
9152 /* Even if the original location is out of scope, the
9153 newly substituted one is not. */
9154 DECL_DEAD_FOR_LOCAL (r) = 0;
9155 DECL_INITIALIZED_P (r) = 0;
9156 DECL_TEMPLATE_INSTANTIATED (r) = 0;
9157 if (type == error_mark_node)
9158 RETURN (error_mark_node);
9159 if (TREE_CODE (type) == FUNCTION_TYPE)
9161 /* It may seem that this case cannot occur, since:
9166 declares a function, not a variable. However:
9169 template <typename T> void g() { T t; }
9170 template void g<f>();
9172 is an attempt to declare a variable with function
9174 error ("variable %qD has function type",
9175 /* R is not yet sufficiently initialized, so we
9176 just use its name. */
9178 RETURN (error_mark_node);
9180 type = complete_type (type);
9181 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
9182 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
9183 type = check_var_type (DECL_NAME (r), type);
9185 if (DECL_HAS_VALUE_EXPR_P (t))
9187 tree ve = DECL_VALUE_EXPR (t);
9188 ve = tsubst_expr (ve, args, complain, in_decl,
9189 /*constant_expression_p=*/false);
9190 SET_DECL_VALUE_EXPR (r, ve);
9193 else if (DECL_SELF_REFERENCE_P (t))
9194 SET_DECL_SELF_REFERENCE_P (r);
9195 TREE_TYPE (r) = type;
9196 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
9197 DECL_CONTEXT (r) = ctx;
9198 /* Clear out the mangled name and RTL for the instantiation. */
9199 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
9200 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9201 SET_DECL_RTL (r, NULL_RTX);
9202 /* The initializer must not be expanded until it is required;
9204 DECL_INITIAL (r) = NULL_TREE;
9205 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
9206 SET_DECL_RTL (r, NULL_RTX);
9207 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
9208 if (TREE_CODE (r) == VAR_DECL)
9210 /* Possibly limit visibility based on template args. */
9211 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
9212 if (DECL_VISIBILITY_SPECIFIED (t))
9214 DECL_VISIBILITY_SPECIFIED (r) = 0;
9216 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
9218 determine_visibility (r);
9220 /* Preserve a typedef that names a type. */
9221 else if (TREE_CODE (r) == TYPE_DECL
9222 && DECL_ORIGINAL_TYPE (t)
9223 && type != error_mark_node)
9225 DECL_ORIGINAL_TYPE (r) = tsubst (DECL_ORIGINAL_TYPE (t),
9226 args, complain, in_decl);
9227 TREE_TYPE (r) = type = build_variant_type_copy (type);
9228 TYPE_NAME (type) = r;
9233 /* A static data member declaration is always marked
9234 external when it is declared in-class, even if an
9235 initializer is present. We mimic the non-template
9237 DECL_EXTERNAL (r) = 1;
9239 register_specialization (r, gen_tmpl, argvec, false, hash);
9240 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
9241 SET_DECL_IMPLICIT_INSTANTIATION (r);
9243 else if (cp_unevaluated_operand)
9245 /* We're substituting this var in a decltype outside of its
9246 scope, such as for a lambda return type. Don't add it to
9247 local_specializations, do perform auto deduction. */
9248 tree auto_node = type_uses_auto (type);
9250 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
9251 /*constant_expression_p=*/false);
9253 if (auto_node && init && describable_type (init))
9255 type = do_auto_deduction (type, init, auto_node);
9256 TREE_TYPE (r) = type;
9260 register_local_specialization (r, t);
9262 TREE_CHAIN (r) = NULL_TREE;
9264 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
9265 (int) ATTR_FLAG_TYPE_IN_PLACE,
9266 args, complain, in_decl);
9277 /* Restore the file and line information. */
9278 input_location = saved_loc;
9283 /* Substitute into the ARG_TYPES of a function type. */
9286 tsubst_arg_types (tree arg_types,
9288 tsubst_flags_t complain,
9291 tree remaining_arg_types;
9292 tree type = NULL_TREE;
9294 tree expanded_args = NULL_TREE;
9297 if (!arg_types || arg_types == void_list_node)
9300 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
9301 args, complain, in_decl);
9302 if (remaining_arg_types == error_mark_node)
9303 return error_mark_node;
9305 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
9307 /* For a pack expansion, perform substitution on the
9308 entire expression. Later on, we'll handle the arguments
9310 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
9311 args, complain, in_decl);
9313 if (TREE_CODE (expanded_args) == TREE_VEC)
9314 /* So that we'll spin through the parameters, one by one. */
9315 i = TREE_VEC_LENGTH (expanded_args);
9318 /* We only partially substituted into the parameter
9319 pack. Our type is TYPE_PACK_EXPANSION. */
9320 type = expanded_args;
9321 expanded_args = NULL_TREE;
9329 type = TREE_VEC_ELT (expanded_args, i);
9331 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
9333 if (type == error_mark_node)
9334 return error_mark_node;
9335 if (VOID_TYPE_P (type))
9337 if (complain & tf_error)
9339 error ("invalid parameter type %qT", type);
9341 error ("in declaration %q+D", in_decl);
9343 return error_mark_node;
9346 /* Do array-to-pointer, function-to-pointer conversion, and ignore
9347 top-level qualifiers as required. */
9348 type = TYPE_MAIN_VARIANT (type_decays_to (type));
9350 /* We do not substitute into default arguments here. The standard
9351 mandates that they be instantiated only when needed, which is
9352 done in build_over_call. */
9353 default_arg = TREE_PURPOSE (arg_types);
9355 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
9357 /* We've instantiated a template before its default arguments
9358 have been parsed. This can happen for a nested template
9359 class, and is not an error unless we require the default
9360 argument in a call of this function. */
9361 remaining_arg_types =
9362 tree_cons (default_arg, type, remaining_arg_types);
9363 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
9364 remaining_arg_types);
9367 remaining_arg_types =
9368 hash_tree_cons (default_arg, type, remaining_arg_types);
9371 return remaining_arg_types;
9374 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
9375 *not* handle the exception-specification for FNTYPE, because the
9376 initial substitution of explicitly provided template parameters
9377 during argument deduction forbids substitution into the
9378 exception-specification:
9382 All references in the function type of the function template to the
9383 corresponding template parameters are replaced by the specified tem-
9384 plate argument values. If a substitution in a template parameter or
9385 in the function type of the function template results in an invalid
9386 type, type deduction fails. [Note: The equivalent substitution in
9387 exception specifications is done only when the function is instanti-
9388 ated, at which point a program is ill-formed if the substitution
9389 results in an invalid type.] */
9392 tsubst_function_type (tree t,
9394 tsubst_flags_t complain,
9401 /* The TYPE_CONTEXT is not used for function/method types. */
9402 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
9404 /* Substitute the return type. */
9405 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9406 if (return_type == error_mark_node)
9407 return error_mark_node;
9408 /* The standard does not presently indicate that creation of a
9409 function type with an invalid return type is a deduction failure.
9410 However, that is clearly analogous to creating an array of "void"
9411 or a reference to a reference. This is core issue #486. */
9412 if (TREE_CODE (return_type) == ARRAY_TYPE
9413 || TREE_CODE (return_type) == FUNCTION_TYPE)
9415 if (complain & tf_error)
9417 if (TREE_CODE (return_type) == ARRAY_TYPE)
9418 error ("function returning an array");
9420 error ("function returning a function");
9422 return error_mark_node;
9425 /* Substitute the argument types. */
9426 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
9428 if (arg_types == error_mark_node)
9429 return error_mark_node;
9431 /* Construct a new type node and return it. */
9432 if (TREE_CODE (t) == FUNCTION_TYPE)
9433 fntype = build_function_type (return_type, arg_types);
9436 tree r = TREE_TYPE (TREE_VALUE (arg_types));
9437 if (! MAYBE_CLASS_TYPE_P (r))
9441 Type deduction may fail for any of the following
9444 -- Attempting to create "pointer to member of T" when T
9445 is not a class type. */
9446 if (complain & tf_error)
9447 error ("creating pointer to member function of non-class type %qT",
9449 return error_mark_node;
9452 fntype = build_method_type_directly (r, return_type,
9453 TREE_CHAIN (arg_types));
9455 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
9456 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
9461 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
9462 ARGS into that specification, and return the substituted
9463 specification. If there is no specification, return NULL_TREE. */
9466 tsubst_exception_specification (tree fntype,
9468 tsubst_flags_t complain,
9474 specs = TYPE_RAISES_EXCEPTIONS (fntype);
9475 new_specs = NULL_TREE;
9478 if (! TREE_VALUE (specs))
9485 tree expanded_specs = NULL_TREE;
9487 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
9489 /* Expand the pack expansion type. */
9490 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
9494 if (expanded_specs == error_mark_node)
9495 return error_mark_node;
9496 else if (TREE_CODE (expanded_specs) == TREE_VEC)
9497 len = TREE_VEC_LENGTH (expanded_specs);
9500 /* We're substituting into a member template, so
9501 we got a TYPE_PACK_EXPANSION back. Add that
9502 expansion and move on. */
9503 gcc_assert (TREE_CODE (expanded_specs)
9504 == TYPE_PACK_EXPANSION);
9505 new_specs = add_exception_specifier (new_specs,
9508 specs = TREE_CHAIN (specs);
9513 for (i = 0; i < len; ++i)
9516 spec = TREE_VEC_ELT (expanded_specs, i);
9518 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
9519 if (spec == error_mark_node)
9521 new_specs = add_exception_specifier (new_specs, spec,
9525 specs = TREE_CHAIN (specs);
9531 /* Take the tree structure T and replace template parameters used
9532 therein with the argument vector ARGS. IN_DECL is an associated
9533 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
9534 Issue error and warning messages under control of COMPLAIN. Note
9535 that we must be relatively non-tolerant of extensions here, in
9536 order to preserve conformance; if we allow substitutions that
9537 should not be allowed, we may allow argument deductions that should
9538 not succeed, and therefore report ambiguous overload situations
9539 where there are none. In theory, we could allow the substitution,
9540 but indicate that it should have failed, and allow our caller to
9541 make sure that the right thing happens, but we don't try to do this
9544 This function is used for dealing with types, decls and the like;
9545 for expressions, use tsubst_expr or tsubst_copy. */
9548 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9552 if (t == NULL_TREE || t == error_mark_node
9553 || t == integer_type_node
9554 || t == void_type_node
9555 || t == char_type_node
9556 || t == unknown_type_node
9557 || TREE_CODE (t) == NAMESPACE_DECL)
9561 return tsubst_decl (t, args, complain);
9563 if (args == NULL_TREE)
9566 if (TREE_CODE (t) == IDENTIFIER_NODE)
9567 type = IDENTIFIER_TYPE_VALUE (t);
9569 type = TREE_TYPE (t);
9571 gcc_assert (type != unknown_type_node);
9573 /* Reuse typedefs. We need to do this to handle dependent attributes,
9574 such as attribute aligned. */
9577 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
9579 tree decl = TYPE_NAME (t);
9581 if (DECL_CLASS_SCOPE_P (decl)
9582 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
9583 && uses_template_parms (DECL_CONTEXT (decl)))
9585 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
9586 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
9587 r = retrieve_specialization (tmpl, gen_args, 0);
9589 else if (DECL_FUNCTION_SCOPE_P (decl)
9590 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
9591 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
9592 r = retrieve_local_specialization (decl);
9594 /* The typedef is from a non-template context. */
9600 r = cp_build_qualified_type_real
9601 (r, cp_type_quals (t) | cp_type_quals (r),
9602 complain | tf_ignore_bad_quals);
9605 /* Else we must be instantiating the typedef, so fall through. */
9609 && TREE_CODE (t) != TYPENAME_TYPE
9610 && TREE_CODE (t) != IDENTIFIER_NODE
9611 && TREE_CODE (t) != FUNCTION_TYPE
9612 && TREE_CODE (t) != METHOD_TYPE)
9613 type = tsubst (type, args, complain, in_decl);
9614 if (type == error_mark_node)
9615 return error_mark_node;
9617 switch (TREE_CODE (t))
9622 return tsubst_aggr_type (t, args, complain, in_decl,
9623 /*entering_scope=*/0);
9626 case IDENTIFIER_NODE:
9638 if (t == integer_type_node)
9641 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
9642 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
9646 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
9648 max = tsubst_expr (omax, args, complain, in_decl,
9649 /*integral_constant_expression_p=*/false);
9651 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
9653 if (TREE_CODE (max) == NOP_EXPR
9654 && TREE_SIDE_EFFECTS (omax)
9655 && !TREE_TYPE (max))
9656 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
9658 max = fold_decl_constant_value (max);
9660 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
9661 with TREE_SIDE_EFFECTS that indicates this is not an integral
9662 constant expression. */
9663 if (processing_template_decl
9664 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
9666 gcc_assert (TREE_CODE (max) == NOP_EXPR);
9667 TREE_SIDE_EFFECTS (max) = 1;
9670 if (TREE_CODE (max) != INTEGER_CST
9671 && !at_function_scope_p ()
9672 && !TREE_SIDE_EFFECTS (max)
9673 && !value_dependent_expression_p (max))
9675 if (complain & tf_error)
9676 error ("array bound is not an integer constant");
9677 return error_mark_node;
9682 Type deduction may fail for any of the following
9685 Attempting to create an array with a size that is
9686 zero or negative. */
9687 if (integer_zerop (max) && !(complain & tf_error))
9688 /* We must fail if performing argument deduction (as
9689 indicated by the state of complain), so that
9690 another substitution can be found. */
9691 return error_mark_node;
9692 else if (TREE_CODE (max) == INTEGER_CST
9693 && INT_CST_LT (max, integer_zero_node))
9695 if (complain & tf_error)
9696 error ("creating array with negative size (%qE)", max);
9698 return error_mark_node;
9701 return compute_array_index_type (NULL_TREE, max);
9704 case TEMPLATE_TYPE_PARM:
9705 case TEMPLATE_TEMPLATE_PARM:
9706 case BOUND_TEMPLATE_TEMPLATE_PARM:
9707 case TEMPLATE_PARM_INDEX:
9712 tree arg = NULL_TREE;
9716 gcc_assert (TREE_VEC_LENGTH (args) > 0);
9717 template_parm_level_and_index (t, &level, &idx);
9719 levels = TMPL_ARGS_DEPTH (args);
9720 if (level <= levels)
9722 arg = TMPL_ARG (args, level, idx);
9724 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
9725 /* See through ARGUMENT_PACK_SELECT arguments. */
9726 arg = ARGUMENT_PACK_SELECT_ARG (arg);
9729 if (arg == error_mark_node)
9730 return error_mark_node;
9731 else if (arg != NULL_TREE)
9733 if (ARGUMENT_PACK_P (arg))
9734 /* If ARG is an argument pack, we don't actually want to
9735 perform a substitution here, because substitutions
9736 for argument packs are only done
9737 element-by-element. We can get to this point when
9738 substituting the type of a non-type template
9739 parameter pack, when that type actually contains
9740 template parameter packs from an outer template, e.g.,
9742 template<typename... Types> struct A {
9743 template<Types... Values> struct B { };
9747 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
9750 gcc_assert (TYPE_P (arg));
9752 /* cv-quals from the template are discarded when
9753 substituting in a function or reference type. */
9754 if (TREE_CODE (arg) == FUNCTION_TYPE
9755 || TREE_CODE (arg) == METHOD_TYPE
9756 || TREE_CODE (arg) == REFERENCE_TYPE)
9757 quals = cp_type_quals (arg);
9759 quals = cp_type_quals (arg) | cp_type_quals (t);
9761 return cp_build_qualified_type_real
9762 (arg, quals, complain | tf_ignore_bad_quals);
9764 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9766 /* We are processing a type constructed from a
9767 template template parameter. */
9768 tree argvec = tsubst (TYPE_TI_ARGS (t),
9769 args, complain, in_decl);
9770 if (argvec == error_mark_node)
9771 return error_mark_node;
9773 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
9774 are resolving nested-types in the signature of a
9775 member function templates. Otherwise ARG is a
9776 TEMPLATE_DECL and is the real template to be
9778 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
9779 arg = TYPE_NAME (arg);
9781 r = lookup_template_class (arg,
9784 /*entering_scope=*/0,
9786 return cp_build_qualified_type_real
9787 (r, TYPE_QUALS (t), complain);
9790 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
9795 /* This can happen during the attempted tsubst'ing in
9796 unify. This means that we don't yet have any information
9797 about the template parameter in question. */
9800 /* If we get here, we must have been looking at a parm for a
9801 more deeply nested template. Make a new version of this
9802 template parameter, but with a lower level. */
9803 switch (TREE_CODE (t))
9805 case TEMPLATE_TYPE_PARM:
9806 case TEMPLATE_TEMPLATE_PARM:
9807 case BOUND_TEMPLATE_TEMPLATE_PARM:
9808 if (cp_type_quals (t))
9810 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
9811 r = cp_build_qualified_type_real
9812 (r, cp_type_quals (t),
9813 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
9814 ? tf_ignore_bad_quals : 0));
9819 TEMPLATE_TYPE_PARM_INDEX (r)
9820 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
9821 r, levels, args, complain);
9822 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
9823 TYPE_MAIN_VARIANT (r) = r;
9824 TYPE_POINTER_TO (r) = NULL_TREE;
9825 TYPE_REFERENCE_TO (r) = NULL_TREE;
9827 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
9828 /* We have reduced the level of the template
9829 template parameter, but not the levels of its
9830 template parameters, so canonical_type_parameter
9831 will not be able to find the canonical template
9832 template parameter for this level. Thus, we
9833 require structural equality checking to compare
9834 TEMPLATE_TEMPLATE_PARMs. */
9835 SET_TYPE_STRUCTURAL_EQUALITY (r);
9836 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
9837 SET_TYPE_STRUCTURAL_EQUALITY (r);
9839 TYPE_CANONICAL (r) = canonical_type_parameter (r);
9841 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9843 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
9845 if (argvec == error_mark_node)
9846 return error_mark_node;
9848 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
9849 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
9854 case TEMPLATE_PARM_INDEX:
9855 r = reduce_template_parm_level (t, type, levels, args, complain);
9867 tree purpose, value, chain;
9869 if (t == void_list_node)
9872 purpose = TREE_PURPOSE (t);
9875 purpose = tsubst (purpose, args, complain, in_decl);
9876 if (purpose == error_mark_node)
9877 return error_mark_node;
9879 value = TREE_VALUE (t);
9882 value = tsubst (value, args, complain, in_decl);
9883 if (value == error_mark_node)
9884 return error_mark_node;
9886 chain = TREE_CHAIN (t);
9887 if (chain && chain != void_type_node)
9889 chain = tsubst (chain, args, complain, in_decl);
9890 if (chain == error_mark_node)
9891 return error_mark_node;
9893 if (purpose == TREE_PURPOSE (t)
9894 && value == TREE_VALUE (t)
9895 && chain == TREE_CHAIN (t))
9897 return hash_tree_cons (purpose, value, chain);
9901 /* We should never be tsubsting a binfo. */
9905 /* A vector of template arguments. */
9907 return tsubst_template_args (t, args, complain, in_decl);
9910 case REFERENCE_TYPE:
9912 enum tree_code code;
9914 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
9917 code = TREE_CODE (t);
9922 Type deduction may fail for any of the following
9925 -- Attempting to create a pointer to reference type.
9926 -- Attempting to create a reference to a reference type or
9927 a reference to void.
9929 Core issue 106 says that creating a reference to a reference
9930 during instantiation is no longer a cause for failure. We
9931 only enforce this check in strict C++98 mode. */
9932 if ((TREE_CODE (type) == REFERENCE_TYPE
9933 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
9934 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
9936 static location_t last_loc;
9938 /* We keep track of the last time we issued this error
9939 message to avoid spewing a ton of messages during a
9940 single bad template instantiation. */
9941 if (complain & tf_error
9942 && last_loc != input_location)
9944 if (TREE_CODE (type) == VOID_TYPE)
9945 error ("forming reference to void");
9947 error ("forming %s to reference type %qT",
9948 (code == POINTER_TYPE) ? "pointer" : "reference",
9950 last_loc = input_location;
9953 return error_mark_node;
9955 else if (code == POINTER_TYPE)
9957 r = build_pointer_type (type);
9958 if (TREE_CODE (type) == METHOD_TYPE)
9959 r = build_ptrmemfunc_type (r);
9961 else if (TREE_CODE (type) == REFERENCE_TYPE)
9962 /* In C++0x, during template argument substitution, when there is an
9963 attempt to create a reference to a reference type, reference
9964 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
9966 "If a template-argument for a template-parameter T names a type
9967 that is a reference to a type A, an attempt to create the type
9968 'lvalue reference to cv T' creates the type 'lvalue reference to
9969 A,' while an attempt to create the type type rvalue reference to
9970 cv T' creates the type T"
9972 r = cp_build_reference_type
9974 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
9976 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
9977 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
9979 if (r != error_mark_node)
9980 /* Will this ever be needed for TYPE_..._TO values? */
9987 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
9988 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
9992 Type deduction may fail for any of the following
9995 -- Attempting to create "pointer to member of T" when T
9996 is not a class type. */
9997 if (complain & tf_error)
9998 error ("creating pointer to member of non-class type %qT", r);
9999 return error_mark_node;
10001 if (TREE_CODE (type) == REFERENCE_TYPE)
10003 if (complain & tf_error)
10004 error ("creating pointer to member reference type %qT", type);
10005 return error_mark_node;
10007 if (TREE_CODE (type) == VOID_TYPE)
10009 if (complain & tf_error)
10010 error ("creating pointer to member of type void");
10011 return error_mark_node;
10013 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
10014 if (TREE_CODE (type) == FUNCTION_TYPE)
10016 /* The type of the implicit object parameter gets its
10017 cv-qualifiers from the FUNCTION_TYPE. */
10019 tree method_type = build_memfn_type (type, r, cp_type_quals (type));
10020 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
10021 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
10025 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
10029 case FUNCTION_TYPE:
10034 fntype = tsubst_function_type (t, args, complain, in_decl);
10035 if (fntype == error_mark_node)
10036 return error_mark_node;
10038 /* Substitute the exception specification. */
10039 specs = tsubst_exception_specification (t, args, complain,
10041 if (specs == error_mark_node)
10042 return error_mark_node;
10044 fntype = build_exception_variant (fntype, specs);
10049 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
10050 if (domain == error_mark_node)
10051 return error_mark_node;
10053 /* As an optimization, we avoid regenerating the array type if
10054 it will obviously be the same as T. */
10055 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
10058 /* These checks should match the ones in grokdeclarator.
10062 The deduction may fail for any of the following reasons:
10064 -- Attempting to create an array with an element type that
10065 is void, a function type, or a reference type, or [DR337]
10066 an abstract class type. */
10067 if (TREE_CODE (type) == VOID_TYPE
10068 || TREE_CODE (type) == FUNCTION_TYPE
10069 || TREE_CODE (type) == REFERENCE_TYPE)
10071 if (complain & tf_error)
10072 error ("creating array of %qT", type);
10073 return error_mark_node;
10075 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
10077 if (complain & tf_error)
10078 error ("creating array of %qT, which is an abstract class type",
10080 return error_mark_node;
10083 r = build_cplus_array_type (type, domain);
10085 if (TYPE_USER_ALIGN (t))
10087 TYPE_ALIGN (r) = TYPE_ALIGN (t);
10088 TYPE_USER_ALIGN (r) = 1;
10097 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10098 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
10100 if (e1 == error_mark_node || e2 == error_mark_node)
10101 return error_mark_node;
10103 return fold_build2_loc (input_location,
10104 TREE_CODE (t), TREE_TYPE (t), e1, e2);
10110 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10111 if (e == error_mark_node)
10112 return error_mark_node;
10114 return fold_build1_loc (input_location, TREE_CODE (t), TREE_TYPE (t), e);
10117 case TYPENAME_TYPE:
10119 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10120 in_decl, /*entering_scope=*/1);
10121 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
10122 complain, in_decl);
10124 if (ctx == error_mark_node || f == error_mark_node)
10125 return error_mark_node;
10127 if (!MAYBE_CLASS_TYPE_P (ctx))
10129 if (complain & tf_error)
10130 error ("%qT is not a class, struct, or union type", ctx);
10131 return error_mark_node;
10133 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
10135 /* Normally, make_typename_type does not require that the CTX
10136 have complete type in order to allow things like:
10138 template <class T> struct S { typename S<T>::X Y; };
10140 But, such constructs have already been resolved by this
10141 point, so here CTX really should have complete type, unless
10142 it's a partial instantiation. */
10143 if (!(complain & tf_no_class_instantiations))
10144 ctx = complete_type (ctx);
10145 if (!COMPLETE_TYPE_P (ctx))
10147 if (complain & tf_error)
10148 cxx_incomplete_type_error (NULL_TREE, ctx);
10149 return error_mark_node;
10153 f = make_typename_type (ctx, f, typename_type,
10154 (complain & tf_error) | tf_keep_type_decl);
10155 if (f == error_mark_node)
10157 if (TREE_CODE (f) == TYPE_DECL)
10159 complain |= tf_ignore_bad_quals;
10163 if (TREE_CODE (f) != TYPENAME_TYPE)
10165 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
10166 error ("%qT resolves to %qT, which is not an enumeration type",
10168 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
10169 error ("%qT resolves to %qT, which is is not a class type",
10173 return cp_build_qualified_type_real
10174 (f, cp_type_quals (f) | cp_type_quals (t), complain);
10177 case UNBOUND_CLASS_TEMPLATE:
10179 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
10180 in_decl, /*entering_scope=*/1);
10181 tree name = TYPE_IDENTIFIER (t);
10182 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
10184 if (ctx == error_mark_node || name == error_mark_node)
10185 return error_mark_node;
10188 parm_list = tsubst_template_parms (parm_list, args, complain);
10189 return make_unbound_class_template (ctx, name, parm_list, complain);
10195 gcc_unreachable ();
10199 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10200 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
10201 /*integral_constant_expression_p=*/false);
10202 if (e1 == error_mark_node || e2 == error_mark_node)
10203 return error_mark_node;
10205 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
10210 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
10211 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
10212 if (e1 == error_mark_node || e2 == error_mark_node)
10213 return error_mark_node;
10215 return build_qualified_name (/*type=*/NULL_TREE,
10216 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
10223 ++cp_unevaluated_operand;
10224 ++c_inhibit_evaluation_warnings;
10226 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
10228 /*integral_constant_expression_p=*/false);
10230 --cp_unevaluated_operand;
10231 --c_inhibit_evaluation_warnings;
10233 type = finish_typeof (type);
10234 return cp_build_qualified_type_real (type,
10236 | cp_type_quals (type),
10240 case DECLTYPE_TYPE:
10244 ++cp_unevaluated_operand;
10245 ++c_inhibit_evaluation_warnings;
10247 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
10249 /*integral_constant_expression_p=*/false);
10251 --cp_unevaluated_operand;
10252 --c_inhibit_evaluation_warnings;
10254 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
10255 type = lambda_capture_field_type (type);
10256 else if (DECLTYPE_FOR_LAMBDA_RETURN (t))
10257 type = lambda_return_type (type);
10259 type = finish_decltype_type
10260 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
10261 return cp_build_qualified_type_real (type,
10263 | cp_type_quals (type),
10267 case TYPE_ARGUMENT_PACK:
10268 case NONTYPE_ARGUMENT_PACK:
10270 tree r = TYPE_P (t)
10271 ? cxx_make_type (TREE_CODE (t))
10272 : make_node (TREE_CODE (t));
10274 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
10278 SET_ARGUMENT_PACK_ARGS (r, packed_out);
10280 /* For template nontype argument packs, also substitute into
10282 if (TREE_CODE (t) == NONTYPE_ARGUMENT_PACK)
10283 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
10290 sorry ("use of %qs in template",
10291 tree_code_name [(int) TREE_CODE (t)]);
10292 return error_mark_node;
10296 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
10297 type of the expression on the left-hand side of the "." or "->"
10301 tsubst_baselink (tree baselink, tree object_type,
10302 tree args, tsubst_flags_t complain, tree in_decl)
10305 tree qualifying_scope;
10308 tree template_args = 0;
10309 bool template_id_p = false;
10311 /* A baselink indicates a function from a base class. Both the
10312 BASELINK_ACCESS_BINFO and the base class referenced may
10313 indicate bases of the template class, rather than the
10314 instantiated class. In addition, lookups that were not
10315 ambiguous before may be ambiguous now. Therefore, we perform
10316 the lookup again. */
10317 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
10318 qualifying_scope = tsubst (qualifying_scope, args,
10319 complain, in_decl);
10320 fns = BASELINK_FUNCTIONS (baselink);
10321 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
10322 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
10324 template_id_p = true;
10325 template_args = TREE_OPERAND (fns, 1);
10326 fns = TREE_OPERAND (fns, 0);
10328 template_args = tsubst_template_args (template_args, args,
10329 complain, in_decl);
10331 name = DECL_NAME (get_first_fn (fns));
10332 if (IDENTIFIER_TYPENAME_P (name))
10333 name = mangle_conv_op_name_for_type (optype);
10334 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
10336 /* If lookup found a single function, mark it as used at this
10337 point. (If it lookup found multiple functions the one selected
10338 later by overload resolution will be marked as used at that
10340 if (BASELINK_P (baselink))
10341 fns = BASELINK_FUNCTIONS (baselink);
10342 if (!template_id_p && !really_overloaded_fn (fns))
10343 mark_used (OVL_CURRENT (fns));
10345 /* Add back the template arguments, if present. */
10346 if (BASELINK_P (baselink) && template_id_p)
10347 BASELINK_FUNCTIONS (baselink)
10348 = build_nt (TEMPLATE_ID_EXPR,
10349 BASELINK_FUNCTIONS (baselink),
10351 /* Update the conversion operator type. */
10352 BASELINK_OPTYPE (baselink) = optype;
10355 object_type = current_class_type;
10356 return adjust_result_of_qualified_name_lookup (baselink,
10361 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
10362 true if the qualified-id will be a postfix-expression in-and-of
10363 itself; false if more of the postfix-expression follows the
10364 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
10368 tsubst_qualified_id (tree qualified_id, tree args,
10369 tsubst_flags_t complain, tree in_decl,
10370 bool done, bool address_p)
10376 tree template_args;
10378 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
10380 /* Figure out what name to look up. */
10381 name = TREE_OPERAND (qualified_id, 1);
10382 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
10384 is_template = true;
10385 template_args = TREE_OPERAND (name, 1);
10387 template_args = tsubst_template_args (template_args, args,
10388 complain, in_decl);
10389 name = TREE_OPERAND (name, 0);
10393 is_template = false;
10394 template_args = NULL_TREE;
10397 /* Substitute into the qualifying scope. When there are no ARGS, we
10398 are just trying to simplify a non-dependent expression. In that
10399 case the qualifying scope may be dependent, and, in any case,
10400 substituting will not help. */
10401 scope = TREE_OPERAND (qualified_id, 0);
10404 scope = tsubst (scope, args, complain, in_decl);
10405 expr = tsubst_copy (name, args, complain, in_decl);
10410 if (dependent_type_p (scope))
10412 tree type = NULL_TREE;
10413 if (DECL_P (expr) && !dependent_scope_p (scope))
10414 type = TREE_TYPE (expr);
10415 return build_qualified_name (type, scope, expr,
10416 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
10419 if (!BASELINK_P (name) && !DECL_P (expr))
10421 if (TREE_CODE (expr) == BIT_NOT_EXPR)
10423 /* A BIT_NOT_EXPR is used to represent a destructor. */
10424 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
10426 error ("qualifying type %qT does not match destructor name ~%qT",
10427 scope, TREE_OPERAND (expr, 0));
10428 expr = error_mark_node;
10431 expr = lookup_qualified_name (scope, complete_dtor_identifier,
10432 /*is_type_p=*/0, false);
10435 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
10436 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
10437 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
10439 if (complain & tf_error)
10441 error ("dependent-name %qE is parsed as a non-type, but "
10442 "instantiation yields a type", qualified_id);
10443 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
10445 return error_mark_node;
10451 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
10453 /* Remember that there was a reference to this entity. */
10457 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
10459 if (complain & tf_error)
10460 qualified_name_lookup_error (scope,
10461 TREE_OPERAND (qualified_id, 1),
10462 expr, input_location);
10463 return error_mark_node;
10467 expr = lookup_template_function (expr, template_args);
10469 if (expr == error_mark_node && complain & tf_error)
10470 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
10471 expr, input_location);
10472 else if (TYPE_P (scope))
10474 expr = (adjust_result_of_qualified_name_lookup
10475 (expr, scope, current_class_type));
10476 expr = (finish_qualified_id_expr
10477 (scope, expr, done, address_p,
10478 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
10479 /*template_arg_p=*/false));
10482 /* Expressions do not generally have reference type. */
10483 if (TREE_CODE (expr) != SCOPE_REF
10484 /* However, if we're about to form a pointer-to-member, we just
10485 want the referenced member referenced. */
10486 && TREE_CODE (expr) != OFFSET_REF)
10487 expr = convert_from_reference (expr);
10492 /* Like tsubst, but deals with expressions. This function just replaces
10493 template parms; to finish processing the resultant expression, use
10497 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10499 enum tree_code code;
10502 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
10505 code = TREE_CODE (t);
10510 r = retrieve_local_specialization (t);
10515 /* This can happen for a parameter name used later in a function
10516 declaration (such as in a late-specified return type). Just
10517 make a dummy decl, since it's only used for its type. */
10518 gcc_assert (cp_unevaluated_operand != 0);
10519 /* We copy T because want to tsubst the PARM_DECL only,
10520 not the following PARM_DECLs that are chained to T. */
10522 r = tsubst_decl (c, args, complain);
10523 /* Give it the template pattern as its context; its true context
10524 hasn't been instantiated yet and this is good enough for
10526 DECL_CONTEXT (r) = DECL_CONTEXT (t);
10529 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
10530 r = ARGUMENT_PACK_SELECT_ARG (r);
10539 if (DECL_TEMPLATE_PARM_P (t))
10540 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
10541 /* There is no need to substitute into namespace-scope
10543 if (DECL_NAMESPACE_SCOPE_P (t))
10545 /* If ARGS is NULL, then T is known to be non-dependent. */
10546 if (args == NULL_TREE)
10547 return integral_constant_value (t);
10549 /* Unfortunately, we cannot just call lookup_name here.
10552 template <int I> int f() {
10554 struct S { void g() { E e = a; } };
10557 When we instantiate f<7>::S::g(), say, lookup_name is not
10558 clever enough to find f<7>::a. */
10560 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
10561 /*entering_scope=*/0);
10563 for (v = TYPE_VALUES (enum_type);
10565 v = TREE_CHAIN (v))
10566 if (TREE_PURPOSE (v) == DECL_NAME (t))
10567 return TREE_VALUE (v);
10569 /* We didn't find the name. That should never happen; if
10570 name-lookup found it during preliminary parsing, we
10571 should find it again here during instantiation. */
10572 gcc_unreachable ();
10577 if (DECL_CONTEXT (t))
10581 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
10582 /*entering_scope=*/1);
10583 if (ctx != DECL_CONTEXT (t))
10585 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
10588 if (complain & tf_error)
10589 error ("using invalid field %qD", t);
10590 return error_mark_node;
10599 case FUNCTION_DECL:
10600 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
10601 || local_variable_p (t))
10602 t = tsubst (t, args, complain, in_decl);
10607 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
10609 case TEMPLATE_DECL:
10610 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
10611 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
10612 args, complain, in_decl);
10613 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
10614 return tsubst (t, args, complain, in_decl);
10615 else if (DECL_CLASS_SCOPE_P (t)
10616 && uses_template_parms (DECL_CONTEXT (t)))
10618 /* Template template argument like the following example need
10621 template <template <class> class TT> struct C {};
10622 template <class T> struct D {
10623 template <class U> struct E {};
10628 We are processing the template argument `E' in #1 for
10629 the template instantiation #2. Originally, `E' is a
10630 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
10631 have to substitute this with one having context `D<int>'. */
10633 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
10634 return lookup_field (context, DECL_NAME(t), 0, false);
10637 /* Ordinary template template argument. */
10641 case REINTERPRET_CAST_EXPR:
10642 case CONST_CAST_EXPR:
10643 case STATIC_CAST_EXPR:
10644 case DYNAMIC_CAST_EXPR:
10647 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10648 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10651 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
10653 /* We only want to compute the number of arguments. */
10654 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
10655 complain, in_decl);
10658 if (TREE_CODE (expanded) == TREE_VEC)
10659 len = TREE_VEC_LENGTH (expanded);
10661 if (expanded == error_mark_node)
10662 return error_mark_node;
10663 else if (PACK_EXPANSION_P (expanded)
10664 || (TREE_CODE (expanded) == TREE_VEC
10666 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
10668 if (TREE_CODE (expanded) == TREE_VEC)
10669 expanded = TREE_VEC_ELT (expanded, len - 1);
10671 if (TYPE_P (expanded))
10672 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
10673 complain & tf_error);
10675 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
10676 complain & tf_error);
10679 return build_int_cst (size_type_node, len);
10685 case TRUTH_NOT_EXPR:
10688 case UNARY_PLUS_EXPR: /* Unary + */
10693 case REALPART_EXPR:
10694 case IMAGPART_EXPR:
10696 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10697 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10699 case COMPONENT_REF:
10704 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
10705 name = TREE_OPERAND (t, 1);
10706 if (TREE_CODE (name) == BIT_NOT_EXPR)
10708 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10709 complain, in_decl);
10710 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10712 else if (TREE_CODE (name) == SCOPE_REF
10713 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
10715 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
10716 complain, in_decl);
10717 name = TREE_OPERAND (name, 1);
10718 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10719 complain, in_decl);
10720 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10721 name = build_qualified_name (/*type=*/NULL_TREE,
10723 /*template_p=*/false);
10725 else if (TREE_CODE (name) == BASELINK)
10726 name = tsubst_baselink (name,
10727 non_reference (TREE_TYPE (object)),
10731 name = tsubst_copy (name, args, complain, in_decl);
10732 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
10738 case TRUNC_DIV_EXPR:
10739 case CEIL_DIV_EXPR:
10740 case FLOOR_DIV_EXPR:
10741 case ROUND_DIV_EXPR:
10742 case EXACT_DIV_EXPR:
10746 case TRUNC_MOD_EXPR:
10747 case FLOOR_MOD_EXPR:
10748 case TRUTH_ANDIF_EXPR:
10749 case TRUTH_ORIF_EXPR:
10750 case TRUTH_AND_EXPR:
10751 case TRUTH_OR_EXPR:
10764 case COMPOUND_EXPR:
10767 case PREDECREMENT_EXPR:
10768 case PREINCREMENT_EXPR:
10769 case POSTDECREMENT_EXPR:
10770 case POSTINCREMENT_EXPR:
10772 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10773 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10776 return build_qualified_name (/*type=*/NULL_TREE,
10777 tsubst_copy (TREE_OPERAND (t, 0),
10778 args, complain, in_decl),
10779 tsubst_copy (TREE_OPERAND (t, 1),
10780 args, complain, in_decl),
10781 QUALIFIED_NAME_IS_TEMPLATE (t));
10786 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10787 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10788 NULL_TREE, NULL_TREE);
10792 int n = VL_EXP_OPERAND_LENGTH (t);
10793 tree result = build_vl_exp (CALL_EXPR, n);
10795 for (i = 0; i < n; i++)
10796 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
10797 complain, in_decl);
10803 case PSEUDO_DTOR_EXPR:
10806 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10807 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10808 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10809 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
10816 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10817 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10818 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10819 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
10826 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10827 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10828 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
10829 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
10833 case TEMPLATE_ID_EXPR:
10835 /* Substituted template arguments */
10836 tree fn = TREE_OPERAND (t, 0);
10837 tree targs = TREE_OPERAND (t, 1);
10839 fn = tsubst_copy (fn, args, complain, in_decl);
10841 targs = tsubst_template_args (targs, args, complain, in_decl);
10843 return lookup_template_function (fn, targs);
10848 tree purpose, value, chain;
10850 if (t == void_list_node)
10853 purpose = TREE_PURPOSE (t);
10855 purpose = tsubst_copy (purpose, args, complain, in_decl);
10856 value = TREE_VALUE (t);
10858 value = tsubst_copy (value, args, complain, in_decl);
10859 chain = TREE_CHAIN (t);
10860 if (chain && chain != void_type_node)
10861 chain = tsubst_copy (chain, args, complain, in_decl);
10862 if (purpose == TREE_PURPOSE (t)
10863 && value == TREE_VALUE (t)
10864 && chain == TREE_CHAIN (t))
10866 return tree_cons (purpose, value, chain);
10871 case ENUMERAL_TYPE:
10873 case TEMPLATE_TYPE_PARM:
10874 case TEMPLATE_TEMPLATE_PARM:
10875 case BOUND_TEMPLATE_TEMPLATE_PARM:
10876 case TEMPLATE_PARM_INDEX:
10878 case REFERENCE_TYPE:
10880 case FUNCTION_TYPE:
10883 case TYPENAME_TYPE:
10884 case UNBOUND_CLASS_TEMPLATE:
10886 case DECLTYPE_TYPE:
10888 return tsubst (t, args, complain, in_decl);
10890 case IDENTIFIER_NODE:
10891 if (IDENTIFIER_TYPENAME_P (t))
10893 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10894 return mangle_conv_op_name_for_type (new_type);
10900 /* This is handled by tsubst_copy_and_build. */
10901 gcc_unreachable ();
10904 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
10906 tsubst (TREE_TYPE (t), args, complain, in_decl));
10908 case CLEANUP_POINT_EXPR:
10909 /* We shouldn't have built any of these during initial template
10910 generation. Instead, they should be built during instantiation
10911 in response to the saved STMT_IS_FULL_EXPR_P setting. */
10912 gcc_unreachable ();
10915 mark_used (TREE_OPERAND (t, 1));
10918 case EXPR_PACK_EXPANSION:
10919 error ("invalid use of pack expansion expression");
10920 return error_mark_node;
10922 case NONTYPE_ARGUMENT_PACK:
10923 error ("use %<...%> to expand argument pack");
10924 return error_mark_node;
10931 /* Like tsubst_copy, but specifically for OpenMP clauses. */
10934 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
10937 tree new_clauses = NULL, nc, oc;
10939 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
10941 nc = copy_node (oc);
10942 OMP_CLAUSE_CHAIN (nc) = new_clauses;
10945 switch (OMP_CLAUSE_CODE (nc))
10947 case OMP_CLAUSE_LASTPRIVATE:
10948 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
10950 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
10951 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
10952 in_decl, /*integral_constant_expression_p=*/false);
10953 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
10954 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
10957 case OMP_CLAUSE_PRIVATE:
10958 case OMP_CLAUSE_SHARED:
10959 case OMP_CLAUSE_FIRSTPRIVATE:
10960 case OMP_CLAUSE_REDUCTION:
10961 case OMP_CLAUSE_COPYIN:
10962 case OMP_CLAUSE_COPYPRIVATE:
10963 case OMP_CLAUSE_IF:
10964 case OMP_CLAUSE_NUM_THREADS:
10965 case OMP_CLAUSE_SCHEDULE:
10966 case OMP_CLAUSE_COLLAPSE:
10967 OMP_CLAUSE_OPERAND (nc, 0)
10968 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
10969 in_decl, /*integral_constant_expression_p=*/false);
10971 case OMP_CLAUSE_NOWAIT:
10972 case OMP_CLAUSE_ORDERED:
10973 case OMP_CLAUSE_DEFAULT:
10974 case OMP_CLAUSE_UNTIED:
10977 gcc_unreachable ();
10981 return finish_omp_clauses (nreverse (new_clauses));
10984 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
10987 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
10990 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
10992 tree purpose, value, chain;
10997 if (TREE_CODE (t) != TREE_LIST)
10998 return tsubst_copy_and_build (t, args, complain, in_decl,
10999 /*function_p=*/false,
11000 /*integral_constant_expression_p=*/false);
11002 if (t == void_list_node)
11005 purpose = TREE_PURPOSE (t);
11007 purpose = RECUR (purpose);
11008 value = TREE_VALUE (t);
11009 if (value && TREE_CODE (value) != LABEL_DECL)
11010 value = RECUR (value);
11011 chain = TREE_CHAIN (t);
11012 if (chain && chain != void_type_node)
11013 chain = RECUR (chain);
11014 return tree_cons (purpose, value, chain);
11018 /* Substitute one OMP_FOR iterator. */
11021 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
11022 tree condv, tree incrv, tree *clauses,
11023 tree args, tsubst_flags_t complain, tree in_decl,
11024 bool integral_constant_expression_p)
11026 #define RECUR(NODE) \
11027 tsubst_expr ((NODE), args, complain, in_decl, \
11028 integral_constant_expression_p)
11029 tree decl, init, cond, incr, auto_node;
11031 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
11032 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
11033 decl = RECUR (TREE_OPERAND (init, 0));
11034 init = TREE_OPERAND (init, 1);
11035 auto_node = type_uses_auto (TREE_TYPE (decl));
11036 if (auto_node && init)
11038 tree init_expr = init;
11039 if (TREE_CODE (init_expr) == DECL_EXPR)
11040 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
11041 init_expr = RECUR (init_expr);
11043 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
11045 gcc_assert (!type_dependent_expression_p (decl));
11047 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
11049 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
11050 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11051 if (TREE_CODE (incr) == MODIFY_EXPR)
11052 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
11053 RECUR (TREE_OPERAND (incr, 1)),
11056 incr = RECUR (incr);
11057 TREE_VEC_ELT (declv, i) = decl;
11058 TREE_VEC_ELT (initv, i) = init;
11059 TREE_VEC_ELT (condv, i) = cond;
11060 TREE_VEC_ELT (incrv, i) = incr;
11064 if (init && TREE_CODE (init) != DECL_EXPR)
11067 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
11069 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
11070 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
11071 && OMP_CLAUSE_DECL (c) == decl)
11073 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
11074 && OMP_CLAUSE_DECL (c) == decl)
11075 error ("iteration variable %qD should not be firstprivate", decl);
11076 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
11077 && OMP_CLAUSE_DECL (c) == decl)
11078 error ("iteration variable %qD should not be reduction", decl);
11082 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
11083 OMP_CLAUSE_DECL (c) = decl;
11084 c = finish_omp_clauses (c);
11087 OMP_CLAUSE_CHAIN (c) = *clauses;
11092 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
11093 if (COMPARISON_CLASS_P (cond))
11094 cond = build2 (TREE_CODE (cond), boolean_type_node,
11095 RECUR (TREE_OPERAND (cond, 0)),
11096 RECUR (TREE_OPERAND (cond, 1)));
11098 cond = RECUR (cond);
11099 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
11100 switch (TREE_CODE (incr))
11102 case PREINCREMENT_EXPR:
11103 case PREDECREMENT_EXPR:
11104 case POSTINCREMENT_EXPR:
11105 case POSTDECREMENT_EXPR:
11106 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
11107 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
11110 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11111 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11113 tree rhs = TREE_OPERAND (incr, 1);
11114 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11115 RECUR (TREE_OPERAND (incr, 0)),
11116 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11117 RECUR (TREE_OPERAND (rhs, 0)),
11118 RECUR (TREE_OPERAND (rhs, 1))));
11121 incr = RECUR (incr);
11124 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
11125 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
11127 tree lhs = RECUR (TREE_OPERAND (incr, 0));
11128 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
11129 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
11130 TREE_TYPE (decl), lhs,
11131 RECUR (TREE_OPERAND (incr, 2))));
11133 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
11134 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
11135 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
11137 tree rhs = TREE_OPERAND (incr, 2);
11138 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
11139 RECUR (TREE_OPERAND (incr, 0)),
11140 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
11141 RECUR (TREE_OPERAND (rhs, 0)),
11142 RECUR (TREE_OPERAND (rhs, 1))));
11145 incr = RECUR (incr);
11148 incr = RECUR (incr);
11152 TREE_VEC_ELT (declv, i) = decl;
11153 TREE_VEC_ELT (initv, i) = init;
11154 TREE_VEC_ELT (condv, i) = cond;
11155 TREE_VEC_ELT (incrv, i) = incr;
11159 /* Like tsubst_copy for expressions, etc. but also does semantic
11163 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
11164 bool integral_constant_expression_p)
11166 #define RECUR(NODE) \
11167 tsubst_expr ((NODE), args, complain, in_decl, \
11168 integral_constant_expression_p)
11172 if (t == NULL_TREE || t == error_mark_node)
11175 if (EXPR_HAS_LOCATION (t))
11176 input_location = EXPR_LOCATION (t);
11177 if (STATEMENT_CODE_P (TREE_CODE (t)))
11178 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
11180 switch (TREE_CODE (t))
11182 case STATEMENT_LIST:
11184 tree_stmt_iterator i;
11185 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
11186 RECUR (tsi_stmt (i));
11190 case CTOR_INITIALIZER:
11191 finish_mem_initializers (tsubst_initializer_list
11192 (TREE_OPERAND (t, 0), args));
11196 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
11200 tmp = RECUR (EXPR_STMT_EXPR (t));
11201 if (EXPR_STMT_STMT_EXPR_RESULT (t))
11202 finish_stmt_expr_expr (tmp, cur_stmt_expr);
11204 finish_expr_stmt (tmp);
11208 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
11216 decl = DECL_EXPR_DECL (t);
11217 if (TREE_CODE (decl) == LABEL_DECL)
11218 finish_label_decl (DECL_NAME (decl));
11219 else if (TREE_CODE (decl) == USING_DECL)
11221 tree scope = USING_DECL_SCOPE (decl);
11222 tree name = DECL_NAME (decl);
11225 scope = RECUR (scope);
11226 decl = lookup_qualified_name (scope, name,
11227 /*is_type_p=*/false,
11228 /*complain=*/false);
11229 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
11230 qualified_name_lookup_error (scope, name, decl, input_location);
11232 do_local_using_decl (decl, scope, name);
11236 init = DECL_INITIAL (decl);
11237 decl = tsubst (decl, args, complain, in_decl);
11238 if (decl != error_mark_node)
11240 /* By marking the declaration as instantiated, we avoid
11241 trying to instantiate it. Since instantiate_decl can't
11242 handle local variables, and since we've already done
11243 all that needs to be done, that's the right thing to
11245 if (TREE_CODE (decl) == VAR_DECL)
11246 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11247 if (TREE_CODE (decl) == VAR_DECL
11248 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
11249 /* Anonymous aggregates are a special case. */
11250 finish_anon_union (decl);
11253 maybe_push_decl (decl);
11254 if (TREE_CODE (decl) == VAR_DECL
11255 && DECL_PRETTY_FUNCTION_P (decl))
11257 /* For __PRETTY_FUNCTION__ we have to adjust the
11259 const char *const name
11260 = cxx_printable_name (current_function_decl, 2);
11261 init = cp_fname_init (name, &TREE_TYPE (decl));
11265 tree t = RECUR (init);
11268 /* If we had an initializer but it
11269 instantiated to nothing,
11270 value-initialize the object. This will
11271 only occur when the initializer was a
11272 pack expansion where the parameter packs
11273 used in that expansion were of length
11275 init = build_value_init (TREE_TYPE (decl));
11280 cp_finish_decl (decl, init, false, NULL_TREE, 0);
11285 /* A DECL_EXPR can also be used as an expression, in the condition
11286 clause of an if/for/while construct. */
11291 stmt = begin_for_stmt ();
11292 RECUR (FOR_INIT_STMT (t));
11293 finish_for_init_stmt (stmt);
11294 tmp = RECUR (FOR_COND (t));
11295 finish_for_cond (tmp, stmt);
11296 tmp = RECUR (FOR_EXPR (t));
11297 finish_for_expr (tmp, stmt);
11298 RECUR (FOR_BODY (t));
11299 finish_for_stmt (stmt);
11303 stmt = begin_while_stmt ();
11304 tmp = RECUR (WHILE_COND (t));
11305 finish_while_stmt_cond (tmp, stmt);
11306 RECUR (WHILE_BODY (t));
11307 finish_while_stmt (stmt);
11311 stmt = begin_do_stmt ();
11312 RECUR (DO_BODY (t));
11313 finish_do_body (stmt);
11314 tmp = RECUR (DO_COND (t));
11315 finish_do_stmt (tmp, stmt);
11319 stmt = begin_if_stmt ();
11320 tmp = RECUR (IF_COND (t));
11321 finish_if_stmt_cond (tmp, stmt);
11322 RECUR (THEN_CLAUSE (t));
11323 finish_then_clause (stmt);
11325 if (ELSE_CLAUSE (t))
11327 begin_else_clause (stmt);
11328 RECUR (ELSE_CLAUSE (t));
11329 finish_else_clause (stmt);
11332 finish_if_stmt (stmt);
11336 if (BIND_EXPR_BODY_BLOCK (t))
11337 stmt = begin_function_body ();
11339 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
11340 ? BCS_TRY_BLOCK : 0);
11342 RECUR (BIND_EXPR_BODY (t));
11344 if (BIND_EXPR_BODY_BLOCK (t))
11345 finish_function_body (stmt);
11347 finish_compound_stmt (stmt);
11351 finish_break_stmt ();
11354 case CONTINUE_STMT:
11355 finish_continue_stmt ();
11359 stmt = begin_switch_stmt ();
11360 tmp = RECUR (SWITCH_STMT_COND (t));
11361 finish_switch_cond (tmp, stmt);
11362 RECUR (SWITCH_STMT_BODY (t));
11363 finish_switch_stmt (stmt);
11366 case CASE_LABEL_EXPR:
11367 finish_case_label (EXPR_LOCATION (t),
11368 RECUR (CASE_LOW (t)),
11369 RECUR (CASE_HIGH (t)));
11374 tree decl = LABEL_EXPR_LABEL (t);
11377 label = finish_label_stmt (DECL_NAME (decl));
11378 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
11379 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
11384 tmp = GOTO_DESTINATION (t);
11385 if (TREE_CODE (tmp) != LABEL_DECL)
11386 /* Computed goto's must be tsubst'd into. On the other hand,
11387 non-computed gotos must not be; the identifier in question
11388 will have no binding. */
11391 tmp = DECL_NAME (tmp);
11392 finish_goto_stmt (tmp);
11396 tmp = finish_asm_stmt
11397 (ASM_VOLATILE_P (t),
11398 RECUR (ASM_STRING (t)),
11399 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
11400 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
11401 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
11402 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
11404 tree asm_expr = tmp;
11405 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
11406 asm_expr = TREE_OPERAND (asm_expr, 0);
11407 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
11414 stmt = begin_try_block ();
11415 RECUR (TRY_STMTS (t));
11416 finish_cleanup_try_block (stmt);
11417 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
11421 tree compound_stmt = NULL_TREE;
11423 if (FN_TRY_BLOCK_P (t))
11424 stmt = begin_function_try_block (&compound_stmt);
11426 stmt = begin_try_block ();
11428 RECUR (TRY_STMTS (t));
11430 if (FN_TRY_BLOCK_P (t))
11431 finish_function_try_block (stmt);
11433 finish_try_block (stmt);
11435 RECUR (TRY_HANDLERS (t));
11436 if (FN_TRY_BLOCK_P (t))
11437 finish_function_handler_sequence (stmt, compound_stmt);
11439 finish_handler_sequence (stmt);
11445 tree decl = HANDLER_PARMS (t);
11449 decl = tsubst (decl, args, complain, in_decl);
11450 /* Prevent instantiate_decl from trying to instantiate
11451 this variable. We've already done all that needs to be
11453 if (decl != error_mark_node)
11454 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11456 stmt = begin_handler ();
11457 finish_handler_parms (decl, stmt);
11458 RECUR (HANDLER_BODY (t));
11459 finish_handler (stmt);
11464 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
11467 case STATIC_ASSERT:
11470 tsubst_expr (STATIC_ASSERT_CONDITION (t),
11473 /*integral_constant_expression_p=*/true);
11474 finish_static_assert (condition,
11475 STATIC_ASSERT_MESSAGE (t),
11476 STATIC_ASSERT_SOURCE_LOCATION (t),
11477 /*member_p=*/false);
11482 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
11483 args, complain, in_decl);
11484 stmt = begin_omp_parallel ();
11485 RECUR (OMP_PARALLEL_BODY (t));
11486 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
11487 = OMP_PARALLEL_COMBINED (t);
11491 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
11492 args, complain, in_decl);
11493 stmt = begin_omp_task ();
11494 RECUR (OMP_TASK_BODY (t));
11495 finish_omp_task (tmp, stmt);
11500 tree clauses, body, pre_body;
11501 tree declv, initv, condv, incrv;
11504 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
11505 args, complain, in_decl);
11506 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11507 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11508 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11509 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11511 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
11512 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
11513 &clauses, args, complain, in_decl,
11514 integral_constant_expression_p);
11516 stmt = begin_omp_structured_block ();
11518 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
11519 if (TREE_VEC_ELT (initv, i) == NULL
11520 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
11521 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
11522 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
11524 tree init = RECUR (TREE_VEC_ELT (initv, i));
11525 gcc_assert (init == TREE_VEC_ELT (declv, i));
11526 TREE_VEC_ELT (initv, i) = NULL_TREE;
11530 tree decl_expr = TREE_VEC_ELT (initv, i);
11531 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
11532 gcc_assert (init != NULL);
11533 TREE_VEC_ELT (initv, i) = RECUR (init);
11534 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
11536 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
11539 pre_body = push_stmt_list ();
11540 RECUR (OMP_FOR_PRE_BODY (t));
11541 pre_body = pop_stmt_list (pre_body);
11543 body = push_stmt_list ();
11544 RECUR (OMP_FOR_BODY (t));
11545 body = pop_stmt_list (body);
11547 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
11548 body, pre_body, clauses);
11550 add_stmt (finish_omp_structured_block (stmt));
11556 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
11557 stmt = push_stmt_list ();
11558 RECUR (OMP_BODY (t));
11559 stmt = pop_stmt_list (stmt);
11562 OMP_BODY (t) = stmt;
11563 OMP_CLAUSES (t) = tmp;
11571 stmt = push_stmt_list ();
11572 RECUR (OMP_BODY (t));
11573 stmt = pop_stmt_list (stmt);
11576 OMP_BODY (t) = stmt;
11581 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
11583 tree op1 = TREE_OPERAND (t, 1);
11584 tree lhs = RECUR (TREE_OPERAND (op1, 0));
11585 tree rhs = RECUR (TREE_OPERAND (op1, 1));
11586 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
11590 case EXPR_PACK_EXPANSION:
11591 error ("invalid use of pack expansion expression");
11592 return error_mark_node;
11594 case NONTYPE_ARGUMENT_PACK:
11595 error ("use %<...%> to expand argument pack");
11596 return error_mark_node;
11599 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
11601 return tsubst_copy_and_build (t, args, complain, in_decl,
11602 /*function_p=*/false,
11603 integral_constant_expression_p);
11610 /* T is a postfix-expression that is not being used in a function
11611 call. Return the substituted version of T. */
11614 tsubst_non_call_postfix_expression (tree t, tree args,
11615 tsubst_flags_t complain,
11618 if (TREE_CODE (t) == SCOPE_REF)
11619 t = tsubst_qualified_id (t, args, complain, in_decl,
11620 /*done=*/false, /*address_p=*/false);
11622 t = tsubst_copy_and_build (t, args, complain, in_decl,
11623 /*function_p=*/false,
11624 /*integral_constant_expression_p=*/false);
11629 /* Like tsubst but deals with expressions and performs semantic
11630 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
11633 tsubst_copy_and_build (tree t,
11635 tsubst_flags_t complain,
11638 bool integral_constant_expression_p)
11640 #define RECUR(NODE) \
11641 tsubst_copy_and_build (NODE, args, complain, in_decl, \
11642 /*function_p=*/false, \
11643 integral_constant_expression_p)
11647 if (t == NULL_TREE || t == error_mark_node)
11650 switch (TREE_CODE (t))
11654 /* Fall through. */
11655 case IDENTIFIER_NODE:
11659 bool non_integral_constant_expression_p;
11660 const char *error_msg;
11662 if (IDENTIFIER_TYPENAME_P (t))
11664 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11665 t = mangle_conv_op_name_for_type (new_type);
11668 /* Look up the name. */
11669 decl = lookup_name (t);
11671 /* By convention, expressions use ERROR_MARK_NODE to indicate
11672 failure, not NULL_TREE. */
11673 if (decl == NULL_TREE)
11674 decl = error_mark_node;
11676 decl = finish_id_expression (t, decl, NULL_TREE,
11678 integral_constant_expression_p,
11679 /*allow_non_integral_constant_expression_p=*/false,
11680 &non_integral_constant_expression_p,
11681 /*template_p=*/false,
11683 /*address_p=*/false,
11684 /*template_arg_p=*/false,
11689 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
11690 decl = unqualified_name_lookup_error (decl);
11694 case TEMPLATE_ID_EXPR:
11697 tree templ = RECUR (TREE_OPERAND (t, 0));
11698 tree targs = TREE_OPERAND (t, 1);
11701 targs = tsubst_template_args (targs, args, complain, in_decl);
11703 if (TREE_CODE (templ) == COMPONENT_REF)
11705 object = TREE_OPERAND (templ, 0);
11706 templ = TREE_OPERAND (templ, 1);
11709 object = NULL_TREE;
11710 templ = lookup_template_function (templ, targs);
11713 return build3 (COMPONENT_REF, TREE_TYPE (templ),
11714 object, templ, NULL_TREE);
11716 return baselink_for_fns (templ);
11721 tree r = RECUR (TREE_OPERAND (t, 0));
11723 if (REFERENCE_REF_P (t))
11725 /* A type conversion to reference type will be enclosed in
11726 such an indirect ref, but the substitution of the cast
11727 will have also added such an indirect ref. */
11728 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
11729 r = convert_from_reference (r);
11732 r = build_x_indirect_ref (r, "unary *", complain);
11738 (tsubst (TREE_TYPE (t), args, complain, in_decl),
11739 RECUR (TREE_OPERAND (t, 0)));
11742 case REINTERPRET_CAST_EXPR:
11743 case CONST_CAST_EXPR:
11744 case DYNAMIC_CAST_EXPR:
11745 case STATIC_CAST_EXPR:
11750 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11751 if (integral_constant_expression_p
11752 && !cast_valid_in_integral_constant_expression_p (type))
11754 if (complain & tf_error)
11755 error ("a cast to a type other than an integral or "
11756 "enumeration type cannot appear in a constant-expression");
11757 return error_mark_node;
11760 op = RECUR (TREE_OPERAND (t, 0));
11762 switch (TREE_CODE (t))
11765 return build_functional_cast (type, op, complain);
11766 case REINTERPRET_CAST_EXPR:
11767 return build_reinterpret_cast (type, op, complain);
11768 case CONST_CAST_EXPR:
11769 return build_const_cast (type, op, complain);
11770 case DYNAMIC_CAST_EXPR:
11771 return build_dynamic_cast (type, op, complain);
11772 case STATIC_CAST_EXPR:
11773 return build_static_cast (type, op, complain);
11775 gcc_unreachable ();
11779 case POSTDECREMENT_EXPR:
11780 case POSTINCREMENT_EXPR:
11781 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11782 args, complain, in_decl);
11783 return build_x_unary_op (TREE_CODE (t), op1, complain);
11785 case PREDECREMENT_EXPR:
11786 case PREINCREMENT_EXPR:
11790 case TRUTH_NOT_EXPR:
11791 case UNARY_PLUS_EXPR: /* Unary + */
11792 case REALPART_EXPR:
11793 case IMAGPART_EXPR:
11794 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
11798 op1 = TREE_OPERAND (t, 0);
11799 if (TREE_CODE (op1) == SCOPE_REF)
11800 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
11801 /*done=*/true, /*address_p=*/true);
11803 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
11805 if (TREE_CODE (op1) == LABEL_DECL)
11806 return finish_label_address_expr (DECL_NAME (op1),
11807 EXPR_LOCATION (op1));
11808 return build_x_unary_op (ADDR_EXPR, op1, complain);
11813 case TRUNC_DIV_EXPR:
11814 case CEIL_DIV_EXPR:
11815 case FLOOR_DIV_EXPR:
11816 case ROUND_DIV_EXPR:
11817 case EXACT_DIV_EXPR:
11821 case TRUNC_MOD_EXPR:
11822 case FLOOR_MOD_EXPR:
11823 case TRUTH_ANDIF_EXPR:
11824 case TRUTH_ORIF_EXPR:
11825 case TRUTH_AND_EXPR:
11826 case TRUTH_OR_EXPR:
11841 return build_x_binary_op
11843 RECUR (TREE_OPERAND (t, 0)),
11844 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
11846 : TREE_CODE (TREE_OPERAND (t, 0))),
11847 RECUR (TREE_OPERAND (t, 1)),
11848 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
11850 : TREE_CODE (TREE_OPERAND (t, 1))),
11851 /*overloaded_p=*/NULL,
11855 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
11856 /*address_p=*/false);
11858 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11859 args, complain, in_decl);
11860 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
11863 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11864 return tsubst_copy (t, args, complain, in_decl);
11868 op1 = TREE_OPERAND (t, 0);
11871 /* When there are no ARGS, we are trying to evaluate a
11872 non-dependent expression from the parser. Trying to do
11873 the substitutions may not work. */
11875 op1 = TREE_TYPE (op1);
11879 ++cp_unevaluated_operand;
11880 ++c_inhibit_evaluation_warnings;
11881 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
11882 /*function_p=*/false,
11883 /*integral_constant_expression_p=*/false);
11884 --cp_unevaluated_operand;
11885 --c_inhibit_evaluation_warnings;
11888 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
11889 complain & tf_error);
11891 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
11892 complain & tf_error);
11896 tree r = build_x_modify_expr
11897 (RECUR (TREE_OPERAND (t, 0)),
11898 TREE_CODE (TREE_OPERAND (t, 1)),
11899 RECUR (TREE_OPERAND (t, 2)),
11901 /* TREE_NO_WARNING must be set if either the expression was
11902 parenthesized or it uses an operator such as >>= rather
11903 than plain assignment. In the former case, it was already
11904 set and must be copied. In the latter case,
11905 build_x_modify_expr sets it and it must not be reset
11907 if (TREE_NO_WARNING (t))
11908 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11913 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11914 args, complain, in_decl);
11915 /* Remember that there was a reference to this entity. */
11918 return build_x_arrow (op1);
11922 tree placement = RECUR (TREE_OPERAND (t, 0));
11923 tree init = RECUR (TREE_OPERAND (t, 3));
11924 VEC(tree,gc) *placement_vec;
11925 VEC(tree,gc) *init_vec;
11928 if (placement == NULL_TREE)
11929 placement_vec = NULL;
11932 placement_vec = make_tree_vector ();
11933 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
11934 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
11937 /* If there was an initializer in the original tree, but it
11938 instantiated to an empty list, then we should pass a
11939 non-NULL empty vector to tell build_new that it was an
11940 empty initializer() rather than no initializer. This can
11941 only happen when the initializer is a pack expansion whose
11942 parameter packs are of length zero. */
11943 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
11947 init_vec = make_tree_vector ();
11948 if (init == void_zero_node)
11949 gcc_assert (init_vec != NULL);
11952 for (; init != NULL_TREE; init = TREE_CHAIN (init))
11953 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
11957 ret = build_new (&placement_vec,
11958 RECUR (TREE_OPERAND (t, 1)),
11959 RECUR (TREE_OPERAND (t, 2)),
11961 NEW_EXPR_USE_GLOBAL (t),
11964 if (placement_vec != NULL)
11965 release_tree_vector (placement_vec);
11966 if (init_vec != NULL)
11967 release_tree_vector (init_vec);
11973 return delete_sanity
11974 (RECUR (TREE_OPERAND (t, 0)),
11975 RECUR (TREE_OPERAND (t, 1)),
11976 DELETE_EXPR_USE_VEC (t),
11977 DELETE_EXPR_USE_GLOBAL (t));
11979 case COMPOUND_EXPR:
11980 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
11981 RECUR (TREE_OPERAND (t, 1)),
11987 VEC(tree,gc) *call_args;
11988 unsigned int nargs, i;
11993 function = CALL_EXPR_FN (t);
11994 /* When we parsed the expression, we determined whether or
11995 not Koenig lookup should be performed. */
11996 koenig_p = KOENIG_LOOKUP_P (t);
11997 if (TREE_CODE (function) == SCOPE_REF)
11999 qualified_p = true;
12000 function = tsubst_qualified_id (function, args, complain, in_decl,
12002 /*address_p=*/false);
12006 if (TREE_CODE (function) == COMPONENT_REF)
12008 tree op = TREE_OPERAND (function, 1);
12010 qualified_p = (TREE_CODE (op) == SCOPE_REF
12011 || (BASELINK_P (op)
12012 && BASELINK_QUALIFIED_P (op)));
12015 qualified_p = false;
12017 function = tsubst_copy_and_build (function, args, complain,
12020 integral_constant_expression_p);
12022 if (BASELINK_P (function))
12023 qualified_p = true;
12026 nargs = call_expr_nargs (t);
12027 call_args = make_tree_vector ();
12028 for (i = 0; i < nargs; ++i)
12030 tree arg = CALL_EXPR_ARG (t, i);
12032 if (!PACK_EXPANSION_P (arg))
12033 VEC_safe_push (tree, gc, call_args,
12034 RECUR (CALL_EXPR_ARG (t, i)));
12037 /* Expand the pack expansion and push each entry onto
12039 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
12040 if (TREE_CODE (arg) == TREE_VEC)
12042 unsigned int len, j;
12044 len = TREE_VEC_LENGTH (arg);
12045 for (j = 0; j < len; ++j)
12047 tree value = TREE_VEC_ELT (arg, j);
12048 if (value != NULL_TREE)
12049 value = convert_from_reference (value);
12050 VEC_safe_push (tree, gc, call_args, value);
12055 /* A partial substitution. Add one entry. */
12056 VEC_safe_push (tree, gc, call_args, arg);
12061 /* We do not perform argument-dependent lookup if normal
12062 lookup finds a non-function, in accordance with the
12063 expected resolution of DR 218. */
12065 && ((is_overloaded_fn (function)
12066 /* If lookup found a member function, the Koenig lookup is
12067 not appropriate, even if an unqualified-name was used
12068 to denote the function. */
12069 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
12070 || TREE_CODE (function) == IDENTIFIER_NODE)
12071 /* Only do this when substitution turns a dependent call
12072 into a non-dependent call. */
12073 && type_dependent_expression_p_push (t)
12074 && !any_type_dependent_arguments_p (call_args))
12075 function = perform_koenig_lookup (function, call_args);
12077 if (TREE_CODE (function) == IDENTIFIER_NODE)
12079 unqualified_name_lookup_error (function);
12080 release_tree_vector (call_args);
12081 return error_mark_node;
12084 /* Remember that there was a reference to this entity. */
12085 if (DECL_P (function))
12086 mark_used (function);
12088 if (TREE_CODE (function) == OFFSET_REF)
12089 ret = build_offset_ref_call_from_tree (function, &call_args);
12090 else if (TREE_CODE (function) == COMPONENT_REF)
12092 if (!BASELINK_P (TREE_OPERAND (function, 1)))
12093 ret = finish_call_expr (function, &call_args,
12094 /*disallow_virtual=*/false,
12095 /*koenig_p=*/false,
12098 ret = (build_new_method_call
12099 (TREE_OPERAND (function, 0),
12100 TREE_OPERAND (function, 1),
12101 &call_args, NULL_TREE,
12102 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
12107 ret = finish_call_expr (function, &call_args,
12108 /*disallow_virtual=*/qualified_p,
12112 release_tree_vector (call_args);
12118 return build_x_conditional_expr
12119 (RECUR (TREE_OPERAND (t, 0)),
12120 RECUR (TREE_OPERAND (t, 1)),
12121 RECUR (TREE_OPERAND (t, 2)),
12124 case PSEUDO_DTOR_EXPR:
12125 return finish_pseudo_destructor_expr
12126 (RECUR (TREE_OPERAND (t, 0)),
12127 RECUR (TREE_OPERAND (t, 1)),
12128 RECUR (TREE_OPERAND (t, 2)));
12132 tree purpose, value, chain;
12134 if (t == void_list_node)
12137 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
12138 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
12140 /* We have pack expansions, so expand those and
12141 create a new list out of it. */
12142 tree purposevec = NULL_TREE;
12143 tree valuevec = NULL_TREE;
12147 /* Expand the argument expressions. */
12148 if (TREE_PURPOSE (t))
12149 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
12150 complain, in_decl);
12151 if (TREE_VALUE (t))
12152 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
12153 complain, in_decl);
12155 /* Build the rest of the list. */
12156 chain = TREE_CHAIN (t);
12157 if (chain && chain != void_type_node)
12158 chain = RECUR (chain);
12160 /* Determine the number of arguments. */
12161 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
12163 len = TREE_VEC_LENGTH (purposevec);
12164 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
12166 else if (TREE_CODE (valuevec) == TREE_VEC)
12167 len = TREE_VEC_LENGTH (valuevec);
12170 /* Since we only performed a partial substitution into
12171 the argument pack, we only return a single list
12173 if (purposevec == TREE_PURPOSE (t)
12174 && valuevec == TREE_VALUE (t)
12175 && chain == TREE_CHAIN (t))
12178 return tree_cons (purposevec, valuevec, chain);
12181 /* Convert the argument vectors into a TREE_LIST */
12185 /* Grab the Ith values. */
12187 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
12190 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
12193 /* Build the list (backwards). */
12194 chain = tree_cons (purpose, value, chain);
12200 purpose = TREE_PURPOSE (t);
12202 purpose = RECUR (purpose);
12203 value = TREE_VALUE (t);
12205 value = RECUR (value);
12206 chain = TREE_CHAIN (t);
12207 if (chain && chain != void_type_node)
12208 chain = RECUR (chain);
12209 if (purpose == TREE_PURPOSE (t)
12210 && value == TREE_VALUE (t)
12211 && chain == TREE_CHAIN (t))
12213 return tree_cons (purpose, value, chain);
12216 case COMPONENT_REF:
12222 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
12223 args, complain, in_decl);
12224 /* Remember that there was a reference to this entity. */
12225 if (DECL_P (object))
12226 mark_used (object);
12227 object_type = TREE_TYPE (object);
12229 member = TREE_OPERAND (t, 1);
12230 if (BASELINK_P (member))
12231 member = tsubst_baselink (member,
12232 non_reference (TREE_TYPE (object)),
12233 args, complain, in_decl);
12235 member = tsubst_copy (member, args, complain, in_decl);
12236 if (member == error_mark_node)
12237 return error_mark_node;
12239 if (object_type && !CLASS_TYPE_P (object_type))
12241 if (SCALAR_TYPE_P (object_type))
12243 tree s = NULL_TREE;
12244 tree dtor = member;
12246 if (TREE_CODE (dtor) == SCOPE_REF)
12248 s = TREE_OPERAND (dtor, 0);
12249 dtor = TREE_OPERAND (dtor, 1);
12251 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
12253 dtor = TREE_OPERAND (dtor, 0);
12255 return finish_pseudo_destructor_expr (object, s, dtor);
12259 else if (TREE_CODE (member) == SCOPE_REF
12260 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
12265 /* Lookup the template functions now that we know what the
12267 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
12268 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
12269 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
12270 /*is_type_p=*/false,
12271 /*complain=*/false);
12272 if (BASELINK_P (member))
12274 BASELINK_FUNCTIONS (member)
12275 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
12277 member = (adjust_result_of_qualified_name_lookup
12278 (member, BINFO_TYPE (BASELINK_BINFO (member)),
12283 qualified_name_lookup_error (object_type, tmpl, member,
12285 return error_mark_node;
12288 else if (TREE_CODE (member) == SCOPE_REF
12289 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
12290 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
12292 if (complain & tf_error)
12294 if (TYPE_P (TREE_OPERAND (member, 0)))
12295 error ("%qT is not a class or namespace",
12296 TREE_OPERAND (member, 0));
12298 error ("%qD is not a class or namespace",
12299 TREE_OPERAND (member, 0));
12301 return error_mark_node;
12303 else if (TREE_CODE (member) == FIELD_DECL)
12304 return finish_non_static_data_member (member, object, NULL_TREE);
12306 return finish_class_member_access_expr (object, member,
12307 /*template_p=*/false,
12313 (RECUR (TREE_OPERAND (t, 0)));
12317 VEC(constructor_elt,gc) *n;
12318 constructor_elt *ce;
12319 unsigned HOST_WIDE_INT idx;
12320 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12321 bool process_index_p;
12323 bool need_copy_p = false;
12326 if (type == error_mark_node)
12327 return error_mark_node;
12329 /* digest_init will do the wrong thing if we let it. */
12330 if (type && TYPE_PTRMEMFUNC_P (type))
12333 /* We do not want to process the index of aggregate
12334 initializers as they are identifier nodes which will be
12335 looked up by digest_init. */
12336 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
12338 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
12339 newlen = VEC_length (constructor_elt, n);
12340 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
12342 if (ce->index && process_index_p)
12343 ce->index = RECUR (ce->index);
12345 if (PACK_EXPANSION_P (ce->value))
12347 /* Substitute into the pack expansion. */
12348 ce->value = tsubst_pack_expansion (ce->value, args, complain,
12351 if (ce->value == error_mark_node)
12353 else if (TREE_VEC_LENGTH (ce->value) == 1)
12354 /* Just move the argument into place. */
12355 ce->value = TREE_VEC_ELT (ce->value, 0);
12358 /* Update the length of the final CONSTRUCTOR
12359 arguments vector, and note that we will need to
12361 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
12362 need_copy_p = true;
12366 ce->value = RECUR (ce->value);
12371 VEC(constructor_elt,gc) *old_n = n;
12373 n = VEC_alloc (constructor_elt, gc, newlen);
12374 for (idx = 0; VEC_iterate (constructor_elt, old_n, idx, ce);
12377 if (TREE_CODE (ce->value) == TREE_VEC)
12379 int i, len = TREE_VEC_LENGTH (ce->value);
12380 for (i = 0; i < len; ++i)
12381 CONSTRUCTOR_APPEND_ELT (n, 0,
12382 TREE_VEC_ELT (ce->value, i));
12385 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
12389 r = build_constructor (init_list_type_node, n);
12390 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
12392 if (TREE_HAS_CONSTRUCTOR (t))
12393 return finish_compound_literal (type, r);
12400 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
12401 if (TYPE_P (operand_0))
12402 return get_typeid (operand_0);
12403 return build_typeid (operand_0);
12413 tree r = tsubst_copy (t, args, complain, in_decl);
12415 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
12416 /* If the original type was a reference, we'll be wrapped in
12417 the appropriate INDIRECT_REF. */
12418 r = convert_from_reference (r);
12423 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
12424 tsubst_copy (TREE_TYPE (t), args, complain,
12427 case OFFSETOF_EXPR:
12428 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
12432 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
12433 complain, in_decl);
12435 tree type2 = TRAIT_EXPR_TYPE2 (t);
12437 type2 = tsubst_copy (type2, args, complain, in_decl);
12439 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
12444 tree old_stmt_expr = cur_stmt_expr;
12445 tree stmt_expr = begin_stmt_expr ();
12447 cur_stmt_expr = stmt_expr;
12448 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
12449 integral_constant_expression_p);
12450 stmt_expr = finish_stmt_expr (stmt_expr, false);
12451 cur_stmt_expr = old_stmt_expr;
12457 t = tsubst_copy (t, args, complain, in_decl);
12458 /* As in finish_id_expression, we resolve enumeration constants
12459 to their underlying values. */
12460 if (TREE_CODE (t) == CONST_DECL)
12462 used_types_insert (TREE_TYPE (t));
12463 return DECL_INITIAL (t);
12469 tree r = build_lambda_expr ();
12471 tree type = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
12472 TREE_TYPE (r) = type;
12473 CLASSTYPE_LAMBDA_EXPR (type) = r;
12475 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
12476 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
12477 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
12478 LAMBDA_EXPR_DISCRIMINATOR (r)
12479 = (LAMBDA_EXPR_DISCRIMINATOR (t));
12480 LAMBDA_EXPR_CAPTURE_LIST (r)
12481 = RECUR (LAMBDA_EXPR_CAPTURE_LIST (t));
12482 LAMBDA_EXPR_THIS_CAPTURE (r)
12483 = RECUR (LAMBDA_EXPR_THIS_CAPTURE (t));
12484 LAMBDA_EXPR_EXTRA_SCOPE (r)
12485 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t));
12487 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
12488 determine_visibility (TYPE_NAME (type));
12489 /* Now that we know visibility, instantiate the type so we have a
12490 declaration of the op() for later calls to lambda_function. */
12491 complete_type (type);
12493 type = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
12495 apply_lambda_return_type (r, type);
12497 return build_lambda_object (r);
12501 /* Handle Objective-C++ constructs, if appropriate. */
12504 = objcp_tsubst_copy_and_build (t, args, complain,
12505 in_decl, /*function_p=*/false);
12509 return tsubst_copy (t, args, complain, in_decl);
12515 /* Verify that the instantiated ARGS are valid. For type arguments,
12516 make sure that the type's linkage is ok. For non-type arguments,
12517 make sure they are constants if they are integral or enumerations.
12518 Emit an error under control of COMPLAIN, and return TRUE on error. */
12521 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
12523 if (ARGUMENT_PACK_P (t))
12525 tree vec = ARGUMENT_PACK_ARGS (t);
12526 int len = TREE_VEC_LENGTH (vec);
12527 bool result = false;
12530 for (i = 0; i < len; ++i)
12531 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
12535 else if (TYPE_P (t))
12537 /* [basic.link]: A name with no linkage (notably, the name
12538 of a class or enumeration declared in a local scope)
12539 shall not be used to declare an entity with linkage.
12540 This implies that names with no linkage cannot be used as
12543 DR 757 relaxes this restriction for C++0x. */
12544 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
12545 : no_linkage_check (t, /*relaxed_p=*/false));
12549 /* DR 488 makes use of a type with no linkage cause
12550 type deduction to fail. */
12551 if (complain & tf_error)
12553 if (TYPE_ANONYMOUS_P (nt))
12554 error ("%qT is/uses anonymous type", t);
12556 error ("template argument for %qD uses local type %qT",
12561 /* In order to avoid all sorts of complications, we do not
12562 allow variably-modified types as template arguments. */
12563 else if (variably_modified_type_p (t, NULL_TREE))
12565 if (complain & tf_error)
12566 error ("%qT is a variably modified type", t);
12570 /* A non-type argument of integral or enumerated type must be a
12572 else if (TREE_TYPE (t)
12573 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
12574 && !TREE_CONSTANT (t))
12576 if (complain & tf_error)
12577 error ("integral expression %qE is not constant", t);
12584 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
12586 int ix, len = DECL_NTPARMS (tmpl);
12587 bool result = false;
12589 for (ix = 0; ix != len; ix++)
12591 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
12594 if (result && (complain & tf_error))
12595 error (" trying to instantiate %qD", tmpl);
12599 /* Instantiate the indicated variable or function template TMPL with
12600 the template arguments in TARG_PTR. */
12603 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
12605 tree targ_ptr = orig_args;
12609 HOST_WIDE_INT saved_processing_template_decl;
12611 if (tmpl == error_mark_node)
12612 return error_mark_node;
12614 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
12616 /* If this function is a clone, handle it specially. */
12617 if (DECL_CLONED_FUNCTION_P (tmpl))
12622 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
12623 DECL_CLONED_FUNCTION. */
12624 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
12625 targ_ptr, complain);
12626 if (spec == error_mark_node)
12627 return error_mark_node;
12629 /* Look for the clone. */
12630 FOR_EACH_CLONE (clone, spec)
12631 if (DECL_NAME (clone) == DECL_NAME (tmpl))
12633 /* We should always have found the clone by now. */
12634 gcc_unreachable ();
12638 /* Check to see if we already have this specialization. */
12639 gen_tmpl = most_general_template (tmpl);
12640 if (tmpl != gen_tmpl)
12641 /* The TMPL is a partial instantiation. To get a full set of
12642 arguments we must add the arguments used to perform the
12643 partial instantiation. */
12644 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
12647 /* It would be nice to avoid hashing here and then again in tsubst_decl,
12648 but it doesn't seem to be on the hot path. */
12649 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
12651 gcc_assert (tmpl == gen_tmpl
12652 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
12654 || fndecl == NULL_TREE);
12656 if (spec != NULL_TREE)
12659 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
12661 return error_mark_node;
12663 /* We are building a FUNCTION_DECL, during which the access of its
12664 parameters and return types have to be checked. However this
12665 FUNCTION_DECL which is the desired context for access checking
12666 is not built yet. We solve this chicken-and-egg problem by
12667 deferring all checks until we have the FUNCTION_DECL. */
12668 push_deferring_access_checks (dk_deferred);
12670 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
12671 (because, for example, we have encountered a non-dependent
12672 function call in the body of a template function and must now
12673 determine which of several overloaded functions will be called),
12674 within the instantiation itself we are not processing a
12676 saved_processing_template_decl = processing_template_decl;
12677 processing_template_decl = 0;
12678 /* Substitute template parameters to obtain the specialization. */
12679 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
12680 targ_ptr, complain, gen_tmpl);
12681 processing_template_decl = saved_processing_template_decl;
12682 if (fndecl == error_mark_node)
12683 return error_mark_node;
12685 /* Now we know the specialization, compute access previously
12687 push_access_scope (fndecl);
12689 /* Some typedefs referenced from within the template code need to be access
12690 checked at template instantiation time, i.e now. These types were
12691 added to the template at parsing time. Let's get those and perfom
12692 the acces checks then. */
12693 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
12694 perform_deferred_access_checks ();
12695 pop_access_scope (fndecl);
12696 pop_deferring_access_checks ();
12698 /* The DECL_TI_TEMPLATE should always be the immediate parent
12699 template, not the most general template. */
12700 DECL_TI_TEMPLATE (fndecl) = tmpl;
12702 /* If we've just instantiated the main entry point for a function,
12703 instantiate all the alternate entry points as well. We do this
12704 by cloning the instantiation of the main entry point, not by
12705 instantiating the template clones. */
12706 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
12707 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
12712 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
12713 NARGS elements of the arguments that are being used when calling
12714 it. TARGS is a vector into which the deduced template arguments
12717 Return zero for success, 2 for an incomplete match that doesn't resolve
12718 all the types, and 1 for complete failure. An error message will be
12719 printed only for an incomplete match.
12721 If FN is a conversion operator, or we are trying to produce a specific
12722 specialization, RETURN_TYPE is the return type desired.
12724 The EXPLICIT_TARGS are explicit template arguments provided via a
12727 The parameter STRICT is one of:
12730 We are deducing arguments for a function call, as in
12731 [temp.deduct.call].
12734 We are deducing arguments for a conversion function, as in
12735 [temp.deduct.conv].
12738 We are deducing arguments when doing an explicit instantiation
12739 as in [temp.explicit], when determining an explicit specialization
12740 as in [temp.expl.spec], or when taking the address of a function
12741 template, as in [temp.deduct.funcaddr]. */
12744 fn_type_unification (tree fn,
12745 tree explicit_targs,
12748 unsigned int nargs,
12750 unification_kind_t strict,
12756 bool incomplete_argument_packs_p = false;
12758 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
12760 fntype = TREE_TYPE (fn);
12761 if (explicit_targs)
12765 The specified template arguments must match the template
12766 parameters in kind (i.e., type, nontype, template), and there
12767 must not be more arguments than there are parameters;
12768 otherwise type deduction fails.
12770 Nontype arguments must match the types of the corresponding
12771 nontype template parameters, or must be convertible to the
12772 types of the corresponding nontype parameters as specified in
12773 _temp.arg.nontype_, otherwise type deduction fails.
12775 All references in the function type of the function template
12776 to the corresponding template parameters are replaced by the
12777 specified template argument values. If a substitution in a
12778 template parameter or in the function type of the function
12779 template results in an invalid type, type deduction fails. */
12780 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
12781 int i, len = TREE_VEC_LENGTH (tparms);
12782 tree converted_args;
12783 bool incomplete = false;
12785 if (explicit_targs == error_mark_node)
12789 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
12790 /*require_all_args=*/false,
12791 /*use_default_args=*/false));
12792 if (converted_args == error_mark_node)
12795 /* Substitute the explicit args into the function type. This is
12796 necessary so that, for instance, explicitly declared function
12797 arguments can match null pointed constants. If we were given
12798 an incomplete set of explicit args, we must not do semantic
12799 processing during substitution as we could create partial
12801 for (i = 0; i < len; i++)
12803 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
12804 bool parameter_pack = false;
12806 /* Dig out the actual parm. */
12807 if (TREE_CODE (parm) == TYPE_DECL
12808 || TREE_CODE (parm) == TEMPLATE_DECL)
12810 parm = TREE_TYPE (parm);
12811 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
12813 else if (TREE_CODE (parm) == PARM_DECL)
12815 parm = DECL_INITIAL (parm);
12816 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
12819 if (parameter_pack)
12823 template_parm_level_and_index (parm, &level, &idx);
12825 /* Mark the argument pack as "incomplete". We could
12826 still deduce more arguments during unification. */
12827 targ = TMPL_ARG (converted_args, level, idx);
12830 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
12831 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
12832 = ARGUMENT_PACK_ARGS (targ);
12835 /* We have some incomplete argument packs. */
12836 incomplete_argument_packs_p = true;
12840 if (incomplete_argument_packs_p)
12841 /* Any substitution is guaranteed to be incomplete if there
12842 are incomplete argument packs, because we can still deduce
12846 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
12848 processing_template_decl += incomplete;
12849 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
12850 processing_template_decl -= incomplete;
12852 if (fntype == error_mark_node)
12855 /* Place the explicitly specified arguments in TARGS. */
12856 for (i = NUM_TMPL_ARGS (converted_args); i--;)
12857 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
12860 /* Never do unification on the 'this' parameter. */
12861 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
12867 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
12868 new_args = XALLOCAVEC (tree, nargs + 1);
12869 new_args[0] = return_type;
12870 memcpy (new_args + 1, args, nargs * sizeof (tree));
12875 /* We allow incomplete unification without an error message here
12876 because the standard doesn't seem to explicitly prohibit it. Our
12877 callers must be ready to deal with unification failures in any
12879 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
12880 targs, parms, args, nargs, /*subr=*/0,
12883 if (result == 0 && incomplete_argument_packs_p)
12885 int i, len = NUM_TMPL_ARGS (targs);
12887 /* Clear the "incomplete" flags on all argument packs. */
12888 for (i = 0; i < len; i++)
12890 tree arg = TREE_VEC_ELT (targs, i);
12891 if (ARGUMENT_PACK_P (arg))
12893 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
12894 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
12899 /* Now that we have bindings for all of the template arguments,
12900 ensure that the arguments deduced for the template template
12901 parameters have compatible template parameter lists. We cannot
12902 check this property before we have deduced all template
12903 arguments, because the template parameter types of a template
12904 template parameter might depend on prior template parameters
12905 deduced after the template template parameter. The following
12906 ill-formed example illustrates this issue:
12908 template<typename T, template<T> class C> void f(C<5>, T);
12910 template<int N> struct X {};
12913 f(X<5>(), 5l); // error: template argument deduction fails
12916 The template parameter list of 'C' depends on the template type
12917 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
12918 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
12919 time that we deduce 'C'. */
12921 && !template_template_parm_bindings_ok_p
12922 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
12926 /* All is well so far. Now, check:
12930 When all template arguments have been deduced, all uses of
12931 template parameters in nondeduced contexts are replaced with
12932 the corresponding deduced argument values. If the
12933 substitution results in an invalid type, as described above,
12934 type deduction fails. */
12936 tree substed = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE);
12937 if (substed == error_mark_node)
12940 /* If we're looking for an exact match, check that what we got
12941 is indeed an exact match. It might not be if some template
12942 parameters are used in non-deduced contexts. */
12943 if (strict == DEDUCE_EXACT)
12948 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
12950 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
12951 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
12952 if (!same_type_p (args[i], TREE_VALUE (sarg)))
12960 /* Adjust types before performing type deduction, as described in
12961 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
12962 sections are symmetric. PARM is the type of a function parameter
12963 or the return type of the conversion function. ARG is the type of
12964 the argument passed to the call, or the type of the value
12965 initialized with the result of the conversion function.
12966 ARG_EXPR is the original argument expression, which may be null. */
12969 maybe_adjust_types_for_deduction (unification_kind_t strict,
12983 /* Swap PARM and ARG throughout the remainder of this
12984 function; the handling is precisely symmetric since PARM
12985 will initialize ARG rather than vice versa. */
12993 /* Core issue #873: Do the DR606 thing (see below) for these cases,
12994 too, but here handle it by stripping the reference from PARM
12995 rather than by adding it to ARG. */
12996 if (TREE_CODE (*parm) == REFERENCE_TYPE
12997 && TYPE_REF_IS_RVALUE (*parm)
12998 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
12999 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
13000 && TREE_CODE (*arg) == REFERENCE_TYPE
13001 && !TYPE_REF_IS_RVALUE (*arg))
13002 *parm = TREE_TYPE (*parm);
13003 /* Nothing else to do in this case. */
13007 gcc_unreachable ();
13010 if (TREE_CODE (*parm) != REFERENCE_TYPE)
13012 /* [temp.deduct.call]
13014 If P is not a reference type:
13016 --If A is an array type, the pointer type produced by the
13017 array-to-pointer standard conversion (_conv.array_) is
13018 used in place of A for type deduction; otherwise,
13020 --If A is a function type, the pointer type produced by
13021 the function-to-pointer standard conversion
13022 (_conv.func_) is used in place of A for type deduction;
13025 --If A is a cv-qualified type, the top level
13026 cv-qualifiers of A's type are ignored for type
13028 if (TREE_CODE (*arg) == ARRAY_TYPE)
13029 *arg = build_pointer_type (TREE_TYPE (*arg));
13030 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
13031 *arg = build_pointer_type (*arg);
13033 *arg = TYPE_MAIN_VARIANT (*arg);
13036 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
13037 of the form T&&, where T is a template parameter, and the argument
13038 is an lvalue, T is deduced as A& */
13039 if (TREE_CODE (*parm) == REFERENCE_TYPE
13040 && TYPE_REF_IS_RVALUE (*parm)
13041 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
13042 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
13043 && arg_expr && real_lvalue_p (arg_expr))
13044 *arg = build_reference_type (*arg);
13046 /* [temp.deduct.call]
13048 If P is a cv-qualified type, the top level cv-qualifiers
13049 of P's type are ignored for type deduction. If P is a
13050 reference type, the type referred to by P is used for
13052 *parm = TYPE_MAIN_VARIANT (*parm);
13053 if (TREE_CODE (*parm) == REFERENCE_TYPE)
13055 *parm = TREE_TYPE (*parm);
13056 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
13059 /* DR 322. For conversion deduction, remove a reference type on parm
13060 too (which has been swapped into ARG). */
13061 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
13062 *arg = TREE_TYPE (*arg);
13067 /* Most parms like fn_type_unification.
13069 If SUBR is 1, we're being called recursively (to unify the
13070 arguments of a function or method parameter of a function
13074 type_unification_real (tree tparms,
13078 unsigned int xnargs,
13080 unification_kind_t strict,
13083 tree parm, arg, arg_expr;
13085 int ntparms = TREE_VEC_LENGTH (tparms);
13087 int saw_undeduced = 0;
13090 unsigned int nargs;
13093 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
13094 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
13095 gcc_assert (ntparms > 0);
13100 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
13101 | UNIFY_ALLOW_DERIVED);
13105 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
13109 sub_strict = UNIFY_ALLOW_NONE;
13113 gcc_unreachable ();
13122 while (parms && parms != void_list_node
13125 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13128 parm = TREE_VALUE (parms);
13129 parms = TREE_CHAIN (parms);
13134 if (arg == error_mark_node)
13136 if (arg == unknown_type_node)
13137 /* We can't deduce anything from this, but we might get all the
13138 template args from other function args. */
13141 /* Conversions will be performed on a function argument that
13142 corresponds with a function parameter that contains only
13143 non-deducible template parameters and explicitly specified
13144 template parameters. */
13145 if (!uses_template_parms (parm))
13150 type = TREE_TYPE (arg);
13154 if (same_type_p (parm, type))
13156 if (strict != DEDUCE_EXACT
13157 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
13166 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
13167 if (type_unknown_p (arg))
13169 /* [temp.deduct.type]
13171 A template-argument can be deduced from a pointer to
13172 function or pointer to member function argument if
13173 the set of overloaded functions does not contain
13174 function templates and at most one of a set of
13175 overloaded functions provides a unique match. */
13176 if (resolve_overloaded_unification
13177 (tparms, targs, parm, arg, strict, sub_strict))
13183 arg = unlowered_expr_type (arg);
13184 if (arg == error_mark_node)
13189 int arg_strict = sub_strict;
13192 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
13195 if (arg == init_list_type_node && arg_expr)
13197 if (unify (tparms, targs, parm, arg, arg_strict))
13204 && parms != void_list_node
13205 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
13207 /* Unify the remaining arguments with the pack expansion type. */
13209 tree parmvec = make_tree_vec (1);
13211 /* Allocate a TREE_VEC and copy in all of the arguments */
13212 argvec = make_tree_vec (nargs - ia);
13213 for (i = 0; ia < nargs; ++ia, ++i)
13214 TREE_VEC_ELT (argvec, i) = args[ia];
13216 /* Copy the parameter into parmvec. */
13217 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
13218 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
13219 /*call_args_p=*/true, /*subr=*/subr))
13222 /* Advance to the end of the list of parameters. */
13223 parms = TREE_CHAIN (parms);
13226 /* Fail if we've reached the end of the parm list, and more args
13227 are present, and the parm list isn't variadic. */
13228 if (ia < nargs && parms == void_list_node)
13230 /* Fail if parms are left and they don't have default values. */
13231 if (parms && parms != void_list_node
13232 && TREE_PURPOSE (parms) == NULL_TREE)
13236 for (i = 0; i < ntparms; i++)
13237 if (!TREE_VEC_ELT (targs, i))
13241 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
13244 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13246 /* If this is an undeduced nontype parameter that depends on
13247 a type parameter, try another pass; its type may have been
13248 deduced from a later argument than the one from which
13249 this parameter can be deduced. */
13250 if (TREE_CODE (tparm) == PARM_DECL
13251 && uses_template_parms (TREE_TYPE (tparm))
13252 && !saw_undeduced++)
13255 /* Core issue #226 (C++0x) [temp.deduct]:
13257 If a template argument has not been deduced, its
13258 default template argument, if any, is used.
13260 When we are in C++98 mode, TREE_PURPOSE will either
13261 be NULL_TREE or ERROR_MARK_NODE, so we do not need
13262 to explicitly check cxx_dialect here. */
13263 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
13265 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
13266 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
13267 arg = tsubst_template_arg (arg, targs, tf_none, NULL_TREE);
13268 arg = convert_template_argument (parm, arg, targs, tf_none,
13270 if (arg == error_mark_node)
13274 TREE_VEC_ELT (targs, i) = arg;
13279 /* If the type parameter is a parameter pack, then it will
13280 be deduced to an empty parameter pack. */
13281 if (template_parameter_pack_p (tparm))
13285 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
13287 arg = make_node (NONTYPE_ARGUMENT_PACK);
13288 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
13289 TREE_CONSTANT (arg) = 1;
13292 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
13294 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
13296 TREE_VEC_ELT (targs, i) = arg;
13306 /* Subroutine of type_unification_real. Args are like the variables
13307 at the call site. ARG is an overloaded function (or template-id);
13308 we try deducing template args from each of the overloads, and if
13309 only one succeeds, we go with that. Modifies TARGS and returns
13310 true on success. */
13313 resolve_overloaded_unification (tree tparms,
13317 unification_kind_t strict,
13320 tree tempargs = copy_node (targs);
13322 tree goodfn = NULL_TREE;
13325 if (TREE_CODE (arg) == ADDR_EXPR)
13327 arg = TREE_OPERAND (arg, 0);
13333 if (TREE_CODE (arg) == COMPONENT_REF)
13334 /* Handle `&x' where `x' is some static or non-static member
13336 arg = TREE_OPERAND (arg, 1);
13338 if (TREE_CODE (arg) == OFFSET_REF)
13339 arg = TREE_OPERAND (arg, 1);
13341 /* Strip baselink information. */
13342 if (BASELINK_P (arg))
13343 arg = BASELINK_FUNCTIONS (arg);
13345 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
13347 /* If we got some explicit template args, we need to plug them into
13348 the affected templates before we try to unify, in case the
13349 explicit args will completely resolve the templates in question. */
13351 tree expl_subargs = TREE_OPERAND (arg, 1);
13352 arg = TREE_OPERAND (arg, 0);
13354 for (; arg; arg = OVL_NEXT (arg))
13356 tree fn = OVL_CURRENT (arg);
13357 tree subargs, elem;
13359 if (TREE_CODE (fn) != TEMPLATE_DECL)
13362 ++processing_template_decl;
13363 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13364 expl_subargs, /*check_ret=*/false);
13367 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
13368 if (try_one_overload (tparms, targs, tempargs, parm,
13369 elem, strict, sub_strict, addr_p)
13370 && (!goodfn || !decls_match (goodfn, elem)))
13376 --processing_template_decl;
13379 else if (TREE_CODE (arg) != OVERLOAD
13380 && TREE_CODE (arg) != FUNCTION_DECL)
13381 /* If ARG is, for example, "(0, &f)" then its type will be unknown
13382 -- but the deduction does not succeed because the expression is
13383 not just the function on its own. */
13386 for (; arg; arg = OVL_NEXT (arg))
13387 if (try_one_overload (tparms, targs, tempargs, parm,
13388 TREE_TYPE (OVL_CURRENT (arg)),
13389 strict, sub_strict, addr_p)
13390 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
13392 goodfn = OVL_CURRENT (arg);
13396 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13397 to function or pointer to member function argument if the set of
13398 overloaded functions does not contain function templates and at most
13399 one of a set of overloaded functions provides a unique match.
13401 So if we found multiple possibilities, we return success but don't
13402 deduce anything. */
13406 int i = TREE_VEC_LENGTH (targs);
13408 if (TREE_VEC_ELT (tempargs, i))
13409 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
13417 /* Core DR 115: In contexts where deduction is done and fails, or in
13418 contexts where deduction is not done, if a template argument list is
13419 specified and it, along with any default template arguments, identifies
13420 a single function template specialization, then the template-id is an
13421 lvalue for the function template specialization. */
13424 resolve_nondeduced_context (tree orig_expr)
13426 tree expr, offset, baselink;
13429 if (!type_unknown_p (orig_expr))
13434 offset = NULL_TREE;
13435 baselink = NULL_TREE;
13437 if (TREE_CODE (expr) == ADDR_EXPR)
13439 expr = TREE_OPERAND (expr, 0);
13442 if (TREE_CODE (expr) == OFFSET_REF)
13445 expr = TREE_OPERAND (expr, 1);
13447 if (TREE_CODE (expr) == BASELINK)
13450 expr = BASELINK_FUNCTIONS (expr);
13453 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
13456 tree goodfn = NULL_TREE;
13458 /* If we got some explicit template args, we need to plug them into
13459 the affected templates before we try to unify, in case the
13460 explicit args will completely resolve the templates in question. */
13462 tree expl_subargs = TREE_OPERAND (expr, 1);
13463 tree arg = TREE_OPERAND (expr, 0);
13464 tree badfn = NULL_TREE;
13465 tree badargs = NULL_TREE;
13467 for (; arg; arg = OVL_NEXT (arg))
13469 tree fn = OVL_CURRENT (arg);
13470 tree subargs, elem;
13472 if (TREE_CODE (fn) != TEMPLATE_DECL)
13475 ++processing_template_decl;
13476 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13477 expl_subargs, /*check_ret=*/false);
13478 if (subargs && !any_dependent_template_arguments_p (subargs))
13480 elem = instantiate_template (fn, subargs, tf_none);
13481 if (elem == error_mark_node)
13486 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
13492 --processing_template_decl;
13498 expr = build_baselink (BASELINK_BINFO (baselink),
13499 BASELINK_ACCESS_BINFO (baselink),
13500 expr, BASELINK_OPTYPE (baselink));
13502 expr = build2 (OFFSET_REF, TREE_TYPE (expr),
13503 TREE_OPERAND (offset, 0), expr);
13505 expr = build_address (expr);
13508 else if (good == 0 && badargs)
13509 /* There were no good options and at least one bad one, so let the
13510 user know what the problem is. */
13511 instantiate_template (badfn, badargs, tf_warning_or_error);
13516 /* Subroutine of resolve_overloaded_unification; does deduction for a single
13517 overload. Fills TARGS with any deduced arguments, or error_mark_node if
13518 different overloads deduce different arguments for a given parm.
13519 ADDR_P is true if the expression for which deduction is being
13520 performed was of the form "& fn" rather than simply "fn".
13522 Returns 1 on success. */
13525 try_one_overload (tree tparms,
13530 unification_kind_t strict,
13538 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13539 to function or pointer to member function argument if the set of
13540 overloaded functions does not contain function templates and at most
13541 one of a set of overloaded functions provides a unique match.
13543 So if this is a template, just return success. */
13545 if (uses_template_parms (arg))
13548 if (TREE_CODE (arg) == METHOD_TYPE)
13549 arg = build_ptrmemfunc_type (build_pointer_type (arg));
13551 arg = build_pointer_type (arg);
13553 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
13555 /* We don't copy orig_targs for this because if we have already deduced
13556 some template args from previous args, unify would complain when we
13557 try to deduce a template parameter for the same argument, even though
13558 there isn't really a conflict. */
13559 nargs = TREE_VEC_LENGTH (targs);
13560 tempargs = make_tree_vec (nargs);
13562 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
13565 /* First make sure we didn't deduce anything that conflicts with
13566 explicitly specified args. */
13567 for (i = nargs; i--; )
13569 tree elt = TREE_VEC_ELT (tempargs, i);
13570 tree oldelt = TREE_VEC_ELT (orig_targs, i);
13574 else if (uses_template_parms (elt))
13575 /* Since we're unifying against ourselves, we will fill in
13576 template args used in the function parm list with our own
13577 template parms. Discard them. */
13578 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
13579 else if (oldelt && !template_args_equal (oldelt, elt))
13583 for (i = nargs; i--; )
13585 tree elt = TREE_VEC_ELT (tempargs, i);
13588 TREE_VEC_ELT (targs, i) = elt;
13594 /* PARM is a template class (perhaps with unbound template
13595 parameters). ARG is a fully instantiated type. If ARG can be
13596 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
13597 TARGS are as for unify. */
13600 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
13602 tree copy_of_targs;
13604 if (!CLASSTYPE_TEMPLATE_INFO (arg)
13605 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
13606 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
13609 /* We need to make a new template argument vector for the call to
13610 unify. If we used TARGS, we'd clutter it up with the result of
13611 the attempted unification, even if this class didn't work out.
13612 We also don't want to commit ourselves to all the unifications
13613 we've already done, since unification is supposed to be done on
13614 an argument-by-argument basis. In other words, consider the
13615 following pathological case:
13617 template <int I, int J, int K>
13620 template <int I, int J>
13621 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
13623 template <int I, int J, int K>
13624 void f(S<I, J, K>, S<I, I, I>);
13633 Now, by the time we consider the unification involving `s2', we
13634 already know that we must have `f<0, 0, 0>'. But, even though
13635 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
13636 because there are two ways to unify base classes of S<0, 1, 2>
13637 with S<I, I, I>. If we kept the already deduced knowledge, we
13638 would reject the possibility I=1. */
13639 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
13641 /* If unification failed, we're done. */
13642 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
13643 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
13649 /* Given a template type PARM and a class type ARG, find the unique
13650 base type in ARG that is an instance of PARM. We do not examine
13651 ARG itself; only its base-classes. If there is not exactly one
13652 appropriate base class, return NULL_TREE. PARM may be the type of
13653 a partial specialization, as well as a plain template type. Used
13657 get_template_base (tree tparms, tree targs, tree parm, tree arg)
13659 tree rval = NULL_TREE;
13662 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
13664 binfo = TYPE_BINFO (complete_type (arg));
13666 /* The type could not be completed. */
13669 /* Walk in inheritance graph order. The search order is not
13670 important, and this avoids multiple walks of virtual bases. */
13671 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
13673 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
13677 /* If there is more than one satisfactory baseclass, then:
13681 If they yield more than one possible deduced A, the type
13685 if (rval && !same_type_p (r, rval))
13695 /* Returns the level of DECL, which declares a template parameter. */
13698 template_decl_level (tree decl)
13700 switch (TREE_CODE (decl))
13703 case TEMPLATE_DECL:
13704 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
13707 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
13710 gcc_unreachable ();
13715 /* Decide whether ARG can be unified with PARM, considering only the
13716 cv-qualifiers of each type, given STRICT as documented for unify.
13717 Returns nonzero iff the unification is OK on that basis. */
13720 check_cv_quals_for_unify (int strict, tree arg, tree parm)
13722 int arg_quals = cp_type_quals (arg);
13723 int parm_quals = cp_type_quals (parm);
13725 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13726 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
13728 /* Although a CVR qualifier is ignored when being applied to a
13729 substituted template parameter ([8.3.2]/1 for example), that
13730 does not apply during deduction [14.8.2.4]/1, (even though
13731 that is not explicitly mentioned, [14.8.2.4]/9 indicates
13732 this). Except when we're allowing additional CV qualifiers
13733 at the outer level [14.8.2.1]/3,1st bullet. */
13734 if ((TREE_CODE (arg) == REFERENCE_TYPE
13735 || TREE_CODE (arg) == FUNCTION_TYPE
13736 || TREE_CODE (arg) == METHOD_TYPE)
13737 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
13740 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
13741 && (parm_quals & TYPE_QUAL_RESTRICT))
13745 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
13746 && (arg_quals & parm_quals) != parm_quals)
13749 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
13750 && (parm_quals & arg_quals) != arg_quals)
13756 /* Determines the LEVEL and INDEX for the template parameter PARM. */
13758 template_parm_level_and_index (tree parm, int* level, int* index)
13760 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13761 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13762 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13764 *index = TEMPLATE_TYPE_IDX (parm);
13765 *level = TEMPLATE_TYPE_LEVEL (parm);
13769 *index = TEMPLATE_PARM_IDX (parm);
13770 *level = TEMPLATE_PARM_LEVEL (parm);
13774 /* Unifies the remaining arguments in PACKED_ARGS with the pack
13775 expansion at the end of PACKED_PARMS. Returns 0 if the type
13776 deduction succeeds, 1 otherwise. STRICT is the same as in
13777 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
13778 call argument list. We'll need to adjust the arguments to make them
13779 types. SUBR tells us if this is from a recursive call to
13780 type_unification_real. */
13782 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
13783 tree packed_args, int strict, bool call_args_p,
13787 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
13788 tree pattern = PACK_EXPANSION_PATTERN (parm);
13789 tree pack, packs = NULL_TREE;
13790 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
13791 int len = TREE_VEC_LENGTH (packed_args);
13793 /* Determine the parameter packs we will be deducing from the
13794 pattern, and record their current deductions. */
13795 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
13796 pack; pack = TREE_CHAIN (pack))
13798 tree parm_pack = TREE_VALUE (pack);
13801 /* Determine the index and level of this parameter pack. */
13802 template_parm_level_and_index (parm_pack, &level, &idx);
13804 /* Keep track of the parameter packs and their corresponding
13806 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
13807 TREE_TYPE (packs) = make_tree_vec (len - start);
13810 /* Loop through all of the arguments that have not yet been
13811 unified and unify each with the pattern. */
13812 for (i = start; i < len; i++)
13814 tree parm = pattern;
13816 /* For each parameter pack, clear out the deduced value so that
13817 we can deduce it again. */
13818 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13821 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13823 TMPL_ARG (targs, level, idx) = NULL_TREE;
13826 /* Unify the pattern with the current argument. */
13828 tree arg = TREE_VEC_ELT (packed_args, i);
13829 tree arg_expr = NULL_TREE;
13830 int arg_strict = strict;
13831 bool skip_arg_p = false;
13837 /* This mirrors what we do in type_unification_real. */
13841 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
13842 | UNIFY_ALLOW_MORE_CV_QUAL
13843 | UNIFY_ALLOW_DERIVED);
13847 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
13851 sub_strict = UNIFY_ALLOW_NONE;
13855 gcc_unreachable ();
13860 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
13861 if (type_unknown_p (arg))
13863 /* [temp.deduct.type] A template-argument can be
13864 deduced from a pointer to function or pointer
13865 to member function argument if the set of
13866 overloaded functions does not contain function
13867 templates and at most one of a set of
13868 overloaded functions provides a unique
13871 if (resolve_overloaded_unification
13872 (tparms, targs, parm, arg,
13873 (unification_kind_t) strict,
13883 arg = unlowered_expr_type (arg);
13884 if (arg == error_mark_node)
13889 arg_strict = sub_strict;
13893 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
13894 &parm, &arg, arg_expr);
13899 if (unify (tparms, targs, parm, arg, arg_strict))
13904 /* For each parameter pack, collect the deduced value. */
13905 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13908 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13910 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
13911 TMPL_ARG (targs, level, idx);
13915 /* Verify that the results of unification with the parameter packs
13916 produce results consistent with what we've seen before, and make
13917 the deduced argument packs available. */
13918 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13920 tree old_pack = TREE_VALUE (pack);
13921 tree new_args = TREE_TYPE (pack);
13922 int i, len = TREE_VEC_LENGTH (new_args);
13923 bool nondeduced_p = false;
13925 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
13926 actually deduce anything. */
13927 for (i = 0; i < len && !nondeduced_p; ++i)
13928 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
13929 nondeduced_p = true;
13933 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
13935 /* Prepend the explicit arguments onto NEW_ARGS. */
13936 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
13937 tree old_args = new_args;
13938 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
13939 int len = explicit_len + TREE_VEC_LENGTH (old_args);
13941 /* Copy the explicit arguments. */
13942 new_args = make_tree_vec (len);
13943 for (i = 0; i < explicit_len; i++)
13944 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
13946 /* Copy the deduced arguments. */
13947 for (; i < len; i++)
13948 TREE_VEC_ELT (new_args, i) =
13949 TREE_VEC_ELT (old_args, i - explicit_len);
13957 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13959 /* Build the deduced *_ARGUMENT_PACK. */
13960 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
13962 result = make_node (NONTYPE_ARGUMENT_PACK);
13963 TREE_TYPE (result) =
13964 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
13965 TREE_CONSTANT (result) = 1;
13968 result = cxx_make_type (TYPE_ARGUMENT_PACK);
13970 SET_ARGUMENT_PACK_ARGS (result, new_args);
13972 /* Note the deduced argument packs for this parameter
13974 TMPL_ARG (targs, level, idx) = result;
13976 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
13977 && (ARGUMENT_PACK_ARGS (old_pack)
13978 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
13980 /* We only had the explicitly-provided arguments before, but
13981 now we have a complete set of arguments. */
13983 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
13984 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13986 /* Keep the original deduced argument pack. */
13987 TMPL_ARG (targs, level, idx) = old_pack;
13989 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
13990 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
13991 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
13993 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
13995 /* Inconsistent unification of this parameter pack. */
14001 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
14003 /* Keep the original deduced argument pack. */
14004 TMPL_ARG (targs, level, idx) = old_pack;
14011 /* Deduce the value of template parameters. TPARMS is the (innermost)
14012 set of template parameters to a template. TARGS is the bindings
14013 for those template parameters, as determined thus far; TARGS may
14014 include template arguments for outer levels of template parameters
14015 as well. PARM is a parameter to a template function, or a
14016 subcomponent of that parameter; ARG is the corresponding argument.
14017 This function attempts to match PARM with ARG in a manner
14018 consistent with the existing assignments in TARGS. If more values
14019 are deduced, then TARGS is updated.
14021 Returns 0 if the type deduction succeeds, 1 otherwise. The
14022 parameter STRICT is a bitwise or of the following flags:
14025 Require an exact match between PARM and ARG.
14026 UNIFY_ALLOW_MORE_CV_QUAL:
14027 Allow the deduced ARG to be more cv-qualified (by qualification
14028 conversion) than ARG.
14029 UNIFY_ALLOW_LESS_CV_QUAL:
14030 Allow the deduced ARG to be less cv-qualified than ARG.
14031 UNIFY_ALLOW_DERIVED:
14032 Allow the deduced ARG to be a template base class of ARG,
14033 or a pointer to a template base class of the type pointed to by
14035 UNIFY_ALLOW_INTEGER:
14036 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
14037 case for more information.
14038 UNIFY_ALLOW_OUTER_LEVEL:
14039 This is the outermost level of a deduction. Used to determine validity
14040 of qualification conversions. A valid qualification conversion must
14041 have const qualified pointers leading up to the inner type which
14042 requires additional CV quals, except at the outer level, where const
14043 is not required [conv.qual]. It would be normal to set this flag in
14044 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
14045 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
14046 This is the outermost level of a deduction, and PARM can be more CV
14047 qualified at this point.
14048 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
14049 This is the outermost level of a deduction, and PARM can be less CV
14050 qualified at this point. */
14053 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
14058 int strict_in = strict;
14060 /* I don't think this will do the right thing with respect to types.
14061 But the only case I've seen it in so far has been array bounds, where
14062 signedness is the only information lost, and I think that will be
14064 while (TREE_CODE (parm) == NOP_EXPR)
14065 parm = TREE_OPERAND (parm, 0);
14067 if (arg == error_mark_node)
14069 if (arg == unknown_type_node
14070 || arg == init_list_type_node)
14071 /* We can't deduce anything from this, but we might get all the
14072 template args from other function args. */
14075 /* If PARM uses template parameters, then we can't bail out here,
14076 even if ARG == PARM, since we won't record unifications for the
14077 template parameters. We might need them if we're trying to
14078 figure out which of two things is more specialized. */
14079 if (arg == parm && !uses_template_parms (parm))
14082 /* Handle init lists early, so the rest of the function can assume
14083 we're dealing with a type. */
14084 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
14088 tree orig_parm = parm;
14090 /* Replace T with std::initializer_list<T> for deduction. */
14091 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14092 && flag_deduce_init_list)
14093 parm = listify (parm);
14095 if (!is_std_init_list (parm))
14096 /* We can only deduce from an initializer list argument if the
14097 parameter is std::initializer_list; otherwise this is a
14098 non-deduced context. */
14101 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
14103 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
14105 int elt_strict = strict;
14106 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
14108 tree type = TREE_TYPE (elt);
14109 /* It should only be possible to get here for a call. */
14110 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
14111 elt_strict |= maybe_adjust_types_for_deduction
14112 (DEDUCE_CALL, &elttype, &type, elt);
14116 if (unify (tparms, targs, elttype, elt, elt_strict))
14120 /* If the std::initializer_list<T> deduction worked, replace the
14121 deduced A with std::initializer_list<A>. */
14122 if (orig_parm != parm)
14124 idx = TEMPLATE_TYPE_IDX (orig_parm);
14125 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14126 targ = listify (targ);
14127 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
14132 /* Immediately reject some pairs that won't unify because of
14133 cv-qualification mismatches. */
14134 if (TREE_CODE (arg) == TREE_CODE (parm)
14136 /* It is the elements of the array which hold the cv quals of an array
14137 type, and the elements might be template type parms. We'll check
14138 when we recurse. */
14139 && TREE_CODE (arg) != ARRAY_TYPE
14140 /* We check the cv-qualifiers when unifying with template type
14141 parameters below. We want to allow ARG `const T' to unify with
14142 PARM `T' for example, when computing which of two templates
14143 is more specialized, for example. */
14144 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
14145 && !check_cv_quals_for_unify (strict_in, arg, parm))
14148 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
14149 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
14150 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
14151 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
14152 strict &= ~UNIFY_ALLOW_DERIVED;
14153 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
14154 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
14156 switch (TREE_CODE (parm))
14158 case TYPENAME_TYPE:
14160 case UNBOUND_CLASS_TEMPLATE:
14161 /* In a type which contains a nested-name-specifier, template
14162 argument values cannot be deduced for template parameters used
14163 within the nested-name-specifier. */
14166 case TEMPLATE_TYPE_PARM:
14167 case TEMPLATE_TEMPLATE_PARM:
14168 case BOUND_TEMPLATE_TEMPLATE_PARM:
14169 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14170 if (tparm == error_mark_node)
14173 if (TEMPLATE_TYPE_LEVEL (parm)
14174 != template_decl_level (tparm))
14175 /* The PARM is not one we're trying to unify. Just check
14176 to see if it matches ARG. */
14177 return (TREE_CODE (arg) == TREE_CODE (parm)
14178 && same_type_p (parm, arg)) ? 0 : 1;
14179 idx = TEMPLATE_TYPE_IDX (parm);
14180 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14181 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
14183 /* Check for mixed types and values. */
14184 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
14185 && TREE_CODE (tparm) != TYPE_DECL)
14186 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14187 && TREE_CODE (tparm) != TEMPLATE_DECL))
14190 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14192 /* ARG must be constructed from a template class or a template
14193 template parameter. */
14194 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
14195 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
14199 tree parmvec = TYPE_TI_ARGS (parm);
14200 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
14202 = DECL_INNERMOST_TEMPLATE_PARMS
14203 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
14205 int parm_variadic_p = 0;
14207 /* The resolution to DR150 makes clear that default
14208 arguments for an N-argument may not be used to bind T
14209 to a template template parameter with fewer than N
14210 parameters. It is not safe to permit the binding of
14211 default arguments as an extension, as that may change
14212 the meaning of a conforming program. Consider:
14214 struct Dense { static const unsigned int dim = 1; };
14216 template <template <typename> class View,
14218 void operator+(float, View<Block> const&);
14220 template <typename Block,
14221 unsigned int Dim = Block::dim>
14222 struct Lvalue_proxy { operator float() const; };
14226 Lvalue_proxy<Dense> p;
14231 Here, if Lvalue_proxy is permitted to bind to View, then
14232 the global operator+ will be used; if they are not, the
14233 Lvalue_proxy will be converted to float. */
14234 if (coerce_template_parms (parm_parms,
14236 TYPE_TI_TEMPLATE (parm),
14238 /*require_all_args=*/true,
14239 /*use_default_args=*/false)
14240 == error_mark_node)
14243 /* Deduce arguments T, i from TT<T> or TT<i>.
14244 We check each element of PARMVEC and ARGVEC individually
14245 rather than the whole TREE_VEC since they can have
14246 different number of elements. */
14248 parmvec = expand_template_argument_pack (parmvec);
14249 argvec = expand_template_argument_pack (argvec);
14251 len = TREE_VEC_LENGTH (parmvec);
14253 /* Check if the parameters end in a pack, making them
14256 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
14257 parm_variadic_p = 1;
14259 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
14262 for (i = 0; i < len - parm_variadic_p; ++i)
14264 if (unify (tparms, targs,
14265 TREE_VEC_ELT (parmvec, i),
14266 TREE_VEC_ELT (argvec, i),
14271 if (parm_variadic_p
14272 && unify_pack_expansion (tparms, targs,
14275 /*call_args_p=*/false,
14279 arg = TYPE_TI_TEMPLATE (arg);
14281 /* Fall through to deduce template name. */
14284 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
14285 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
14287 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
14289 /* Simple cases: Value already set, does match or doesn't. */
14290 if (targ != NULL_TREE && template_args_equal (targ, arg))
14297 /* If PARM is `const T' and ARG is only `int', we don't have
14298 a match unless we are allowing additional qualification.
14299 If ARG is `const int' and PARM is just `T' that's OK;
14300 that binds `const int' to `T'. */
14301 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
14305 /* Consider the case where ARG is `const volatile int' and
14306 PARM is `const T'. Then, T should be `volatile int'. */
14307 arg = cp_build_qualified_type_real
14308 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
14309 if (arg == error_mark_node)
14312 /* Simple cases: Value already set, does match or doesn't. */
14313 if (targ != NULL_TREE && same_type_p (targ, arg))
14318 /* Make sure that ARG is not a variable-sized array. (Note
14319 that were talking about variable-sized arrays (like
14320 `int[n]'), rather than arrays of unknown size (like
14321 `int[]').) We'll get very confused by such a type since
14322 the bound of the array will not be computable in an
14323 instantiation. Besides, such types are not allowed in
14324 ISO C++, so we can do as we please here. */
14325 if (variably_modified_type_p (arg, NULL_TREE))
14328 /* Strip typedefs as in convert_template_argument. */
14329 arg = strip_typedefs (arg);
14332 /* If ARG is a parameter pack or an expansion, we cannot unify
14333 against it unless PARM is also a parameter pack. */
14334 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
14335 && !template_parameter_pack_p (parm))
14338 /* If the argument deduction results is a METHOD_TYPE,
14339 then there is a problem.
14340 METHOD_TYPE doesn't map to any real C++ type the result of
14341 the deduction can not be of that type. */
14342 if (TREE_CODE (arg) == METHOD_TYPE)
14345 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
14348 case TEMPLATE_PARM_INDEX:
14349 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
14350 if (tparm == error_mark_node)
14353 if (TEMPLATE_PARM_LEVEL (parm)
14354 != template_decl_level (tparm))
14355 /* The PARM is not one we're trying to unify. Just check
14356 to see if it matches ARG. */
14357 return !(TREE_CODE (arg) == TREE_CODE (parm)
14358 && cp_tree_equal (parm, arg));
14360 idx = TEMPLATE_PARM_IDX (parm);
14361 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
14364 return !cp_tree_equal (targ, arg);
14366 /* [temp.deduct.type] If, in the declaration of a function template
14367 with a non-type template-parameter, the non-type
14368 template-parameter is used in an expression in the function
14369 parameter-list and, if the corresponding template-argument is
14370 deduced, the template-argument type shall match the type of the
14371 template-parameter exactly, except that a template-argument
14372 deduced from an array bound may be of any integral type.
14373 The non-type parameter might use already deduced type parameters. */
14374 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
14375 if (!TREE_TYPE (arg))
14376 /* Template-parameter dependent expression. Just accept it for now.
14377 It will later be processed in convert_template_argument. */
14379 else if (same_type_p (TREE_TYPE (arg), tparm))
14381 else if ((strict & UNIFY_ALLOW_INTEGER)
14382 && (TREE_CODE (tparm) == INTEGER_TYPE
14383 || TREE_CODE (tparm) == BOOLEAN_TYPE))
14384 /* Convert the ARG to the type of PARM; the deduced non-type
14385 template argument must exactly match the types of the
14386 corresponding parameter. */
14387 arg = fold (build_nop (tparm, arg));
14388 else if (uses_template_parms (tparm))
14389 /* We haven't deduced the type of this parameter yet. Try again
14395 /* If ARG is a parameter pack or an expansion, we cannot unify
14396 against it unless PARM is also a parameter pack. */
14397 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
14398 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
14401 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
14406 /* A pointer-to-member constant can be unified only with
14407 another constant. */
14408 if (TREE_CODE (arg) != PTRMEM_CST)
14411 /* Just unify the class member. It would be useless (and possibly
14412 wrong, depending on the strict flags) to unify also
14413 PTRMEM_CST_CLASS, because we want to be sure that both parm and
14414 arg refer to the same variable, even if through different
14415 classes. For instance:
14417 struct A { int x; };
14420 Unification of &A::x and &B::x must succeed. */
14421 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
14422 PTRMEM_CST_MEMBER (arg), strict);
14427 if (TREE_CODE (arg) != POINTER_TYPE)
14430 /* [temp.deduct.call]
14432 A can be another pointer or pointer to member type that can
14433 be converted to the deduced A via a qualification
14434 conversion (_conv.qual_).
14436 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
14437 This will allow for additional cv-qualification of the
14438 pointed-to types if appropriate. */
14440 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
14441 /* The derived-to-base conversion only persists through one
14442 level of pointers. */
14443 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
14445 return unify (tparms, targs, TREE_TYPE (parm),
14446 TREE_TYPE (arg), strict);
14449 case REFERENCE_TYPE:
14450 if (TREE_CODE (arg) != REFERENCE_TYPE)
14452 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14453 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14456 if (TREE_CODE (arg) != ARRAY_TYPE)
14458 if ((TYPE_DOMAIN (parm) == NULL_TREE)
14459 != (TYPE_DOMAIN (arg) == NULL_TREE))
14461 if (TYPE_DOMAIN (parm) != NULL_TREE)
14468 /* Our representation of array types uses "N - 1" as the
14469 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
14470 not an integer constant. We cannot unify arbitrarily
14471 complex expressions, so we eliminate the MINUS_EXPRs
14473 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
14474 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
14477 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
14478 parm_max = TREE_OPERAND (parm_max, 0);
14480 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
14481 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
14484 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
14485 trying to unify the type of a variable with the type
14486 of a template parameter. For example:
14488 template <unsigned int N>
14489 void f (char (&) [N]);
14496 Here, the type of the ARG will be "int [g(i)]", and
14497 may be a SAVE_EXPR, etc. */
14498 if (TREE_CODE (arg_max) != MINUS_EXPR)
14500 arg_max = TREE_OPERAND (arg_max, 0);
14503 /* If only one of the bounds used a MINUS_EXPR, compensate
14504 by adding one to the other bound. */
14505 if (parm_cst && !arg_cst)
14506 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
14510 else if (arg_cst && !parm_cst)
14511 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
14516 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
14519 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14520 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14527 case ENUMERAL_TYPE:
14529 if (TREE_CODE (arg) != TREE_CODE (parm))
14532 /* We have already checked cv-qualification at the top of the
14534 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
14537 /* As far as unification is concerned, this wins. Later checks
14538 will invalidate it if necessary. */
14541 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
14542 /* Type INTEGER_CST can come from ordinary constant template args. */
14544 while (TREE_CODE (arg) == NOP_EXPR)
14545 arg = TREE_OPERAND (arg, 0);
14547 if (TREE_CODE (arg) != INTEGER_CST)
14549 return !tree_int_cst_equal (parm, arg);
14554 if (TREE_CODE (arg) != TREE_VEC)
14556 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
14558 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
14559 if (unify (tparms, targs,
14560 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
14568 if (TREE_CODE (arg) != TREE_CODE (parm))
14571 if (TYPE_PTRMEMFUNC_P (parm))
14573 if (!TYPE_PTRMEMFUNC_P (arg))
14576 return unify (tparms, targs,
14577 TYPE_PTRMEMFUNC_FN_TYPE (parm),
14578 TYPE_PTRMEMFUNC_FN_TYPE (arg),
14582 if (CLASSTYPE_TEMPLATE_INFO (parm))
14584 tree t = NULL_TREE;
14586 if (strict_in & UNIFY_ALLOW_DERIVED)
14588 /* First, we try to unify the PARM and ARG directly. */
14589 t = try_class_unification (tparms, targs,
14594 /* Fallback to the special case allowed in
14595 [temp.deduct.call]:
14597 If P is a class, and P has the form
14598 template-id, then A can be a derived class of
14599 the deduced A. Likewise, if P is a pointer to
14600 a class of the form template-id, A can be a
14601 pointer to a derived class pointed to by the
14603 t = get_template_base (tparms, targs, parm, arg);
14609 else if (CLASSTYPE_TEMPLATE_INFO (arg)
14610 && (CLASSTYPE_TI_TEMPLATE (parm)
14611 == CLASSTYPE_TI_TEMPLATE (arg)))
14612 /* Perhaps PARM is something like S<U> and ARG is S<int>.
14613 Then, we should unify `int' and `U'. */
14616 /* There's no chance of unification succeeding. */
14619 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
14620 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
14622 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
14627 case FUNCTION_TYPE:
14629 unsigned int nargs;
14634 if (TREE_CODE (arg) != TREE_CODE (parm))
14637 /* CV qualifications for methods can never be deduced, they must
14638 match exactly. We need to check them explicitly here,
14639 because type_unification_real treats them as any other
14640 cv-qualified parameter. */
14641 if (TREE_CODE (parm) == METHOD_TYPE
14642 && (!check_cv_quals_for_unify
14644 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
14645 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
14648 if (unify (tparms, targs, TREE_TYPE (parm),
14649 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
14652 nargs = list_length (TYPE_ARG_TYPES (arg));
14653 args = XALLOCAVEC (tree, nargs);
14654 for (a = TYPE_ARG_TYPES (arg), i = 0;
14655 a != NULL_TREE && a != void_list_node;
14656 a = TREE_CHAIN (a), ++i)
14657 args[i] = TREE_VALUE (a);
14660 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
14661 args, nargs, 1, DEDUCE_EXACT,
14666 /* Unify a pointer to member with a pointer to member function, which
14667 deduces the type of the member as a function type. */
14668 if (TYPE_PTRMEMFUNC_P (arg))
14672 cp_cv_quals cv_quals;
14674 /* Check top-level cv qualifiers */
14675 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
14678 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14679 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
14682 /* Determine the type of the function we are unifying against. */
14683 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
14685 build_function_type (TREE_TYPE (method_type),
14686 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
14688 /* Extract the cv-qualifiers of the member function from the
14689 implicit object parameter and place them on the function
14690 type to be restored later. */
14692 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
14693 fntype = build_qualified_type (fntype, cv_quals);
14694 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
14697 if (TREE_CODE (arg) != OFFSET_TYPE)
14699 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14700 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
14702 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14706 if (DECL_TEMPLATE_PARM_P (parm))
14707 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
14708 if (arg != integral_constant_value (parm))
14713 case TEMPLATE_DECL:
14714 /* Matched cases are handled by the ARG == PARM test above. */
14717 case TYPE_ARGUMENT_PACK:
14718 case NONTYPE_ARGUMENT_PACK:
14720 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
14721 tree packed_args = ARGUMENT_PACK_ARGS (arg);
14722 int i, len = TREE_VEC_LENGTH (packed_parms);
14723 int argslen = TREE_VEC_LENGTH (packed_args);
14724 int parm_variadic_p = 0;
14726 for (i = 0; i < len; ++i)
14728 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
14731 /* We can unify against something with a trailing
14733 parm_variadic_p = 1;
14735 /* Since there is something following the pack
14736 expansion, we cannot unify this template argument
14743 /* If we don't have enough arguments to satisfy the parameters
14744 (not counting the pack expression at the end), or we have
14745 too many arguments for a parameter list that doesn't end in
14746 a pack expression, we can't unify. */
14747 if (argslen < (len - parm_variadic_p)
14748 || (argslen > len && !parm_variadic_p))
14751 /* Unify all of the parameters that precede the (optional)
14752 pack expression. */
14753 for (i = 0; i < len - parm_variadic_p; ++i)
14755 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
14756 TREE_VEC_ELT (packed_args, i), strict))
14760 if (parm_variadic_p)
14761 return unify_pack_expansion (tparms, targs,
14762 packed_parms, packed_args,
14763 strict, /*call_args_p=*/false,
14771 case DECLTYPE_TYPE:
14772 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
14777 /* Unification fails if we hit an error node. */
14781 gcc_assert (EXPR_P (parm));
14783 /* We must be looking at an expression. This can happen with
14787 void foo(S<I>, S<I + 2>);
14789 This is a "nondeduced context":
14793 The nondeduced contexts are:
14795 --A type that is a template-id in which one or more of
14796 the template-arguments is an expression that references
14797 a template-parameter.
14799 In these cases, we assume deduction succeeded, but don't
14800 actually infer any unifications. */
14802 if (!uses_template_parms (parm)
14803 && !template_args_equal (parm, arg))
14810 /* Note that DECL can be defined in this translation unit, if
14814 mark_definable (tree decl)
14817 DECL_NOT_REALLY_EXTERN (decl) = 1;
14818 FOR_EACH_CLONE (clone, decl)
14819 DECL_NOT_REALLY_EXTERN (clone) = 1;
14822 /* Called if RESULT is explicitly instantiated, or is a member of an
14823 explicitly instantiated class. */
14826 mark_decl_instantiated (tree result, int extern_p)
14828 SET_DECL_EXPLICIT_INSTANTIATION (result);
14830 /* If this entity has already been written out, it's too late to
14831 make any modifications. */
14832 if (TREE_ASM_WRITTEN (result))
14835 if (TREE_CODE (result) != FUNCTION_DECL)
14836 /* The TREE_PUBLIC flag for function declarations will have been
14837 set correctly by tsubst. */
14838 TREE_PUBLIC (result) = 1;
14840 /* This might have been set by an earlier implicit instantiation. */
14841 DECL_COMDAT (result) = 0;
14844 DECL_NOT_REALLY_EXTERN (result) = 0;
14847 mark_definable (result);
14848 /* Always make artificials weak. */
14849 if (DECL_ARTIFICIAL (result) && flag_weak)
14850 comdat_linkage (result);
14851 /* For WIN32 we also want to put explicit instantiations in
14852 linkonce sections. */
14853 else if (TREE_PUBLIC (result))
14854 maybe_make_one_only (result);
14857 /* If EXTERN_P, then this function will not be emitted -- unless
14858 followed by an explicit instantiation, at which point its linkage
14859 will be adjusted. If !EXTERN_P, then this function will be
14860 emitted here. In neither circumstance do we want
14861 import_export_decl to adjust the linkage. */
14862 DECL_INTERFACE_KNOWN (result) = 1;
14865 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
14866 important template arguments. If any are missing, we check whether
14867 they're important by using error_mark_node for substituting into any
14868 args that were used for partial ordering (the ones between ARGS and END)
14869 and seeing if it bubbles up. */
14872 check_undeduced_parms (tree targs, tree args, tree end)
14874 bool found = false;
14876 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
14877 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
14880 TREE_VEC_ELT (targs, i) = error_mark_node;
14884 for (; args != end; args = TREE_CHAIN (args))
14886 tree substed = tsubst (TREE_VALUE (args), targs, tf_none, NULL_TREE);
14887 if (substed == error_mark_node)
14894 /* Given two function templates PAT1 and PAT2, return:
14896 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
14897 -1 if PAT2 is more specialized than PAT1.
14898 0 if neither is more specialized.
14900 LEN indicates the number of parameters we should consider
14901 (defaulted parameters should not be considered).
14903 The 1998 std underspecified function template partial ordering, and
14904 DR214 addresses the issue. We take pairs of arguments, one from
14905 each of the templates, and deduce them against each other. One of
14906 the templates will be more specialized if all the *other*
14907 template's arguments deduce against its arguments and at least one
14908 of its arguments *does* *not* deduce against the other template's
14909 corresponding argument. Deduction is done as for class templates.
14910 The arguments used in deduction have reference and top level cv
14911 qualifiers removed. Iff both arguments were originally reference
14912 types *and* deduction succeeds in both directions, the template
14913 with the more cv-qualified argument wins for that pairing (if
14914 neither is more cv-qualified, they both are equal). Unlike regular
14915 deduction, after all the arguments have been deduced in this way,
14916 we do *not* verify the deduced template argument values can be
14917 substituted into non-deduced contexts.
14919 The logic can be a bit confusing here, because we look at deduce1 and
14920 targs1 to see if pat2 is at least as specialized, and vice versa; if we
14921 can find template arguments for pat1 to make arg1 look like arg2, that
14922 means that arg2 is at least as specialized as arg1. */
14925 more_specialized_fn (tree pat1, tree pat2, int len)
14927 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
14928 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
14929 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
14930 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
14931 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
14932 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
14933 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
14934 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
14935 tree origs1, origs2;
14936 bool lose1 = false;
14937 bool lose2 = false;
14939 /* Remove the this parameter from non-static member functions. If
14940 one is a non-static member function and the other is not a static
14941 member function, remove the first parameter from that function
14942 also. This situation occurs for operator functions where we
14943 locate both a member function (with this pointer) and non-member
14944 operator (with explicit first operand). */
14945 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
14947 len--; /* LEN is the number of significant arguments for DECL1 */
14948 args1 = TREE_CHAIN (args1);
14949 if (!DECL_STATIC_FUNCTION_P (decl2))
14950 args2 = TREE_CHAIN (args2);
14952 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
14954 args2 = TREE_CHAIN (args2);
14955 if (!DECL_STATIC_FUNCTION_P (decl1))
14958 args1 = TREE_CHAIN (args1);
14962 /* If only one is a conversion operator, they are unordered. */
14963 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
14966 /* Consider the return type for a conversion function */
14967 if (DECL_CONV_FN_P (decl1))
14969 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
14970 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
14974 processing_template_decl++;
14980 /* Stop when an ellipsis is seen. */
14981 && args1 != NULL_TREE && args2 != NULL_TREE)
14983 tree arg1 = TREE_VALUE (args1);
14984 tree arg2 = TREE_VALUE (args2);
14985 int deduce1, deduce2;
14989 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
14990 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
14992 /* When both arguments are pack expansions, we need only
14993 unify the patterns themselves. */
14994 arg1 = PACK_EXPANSION_PATTERN (arg1);
14995 arg2 = PACK_EXPANSION_PATTERN (arg2);
14997 /* This is the last comparison we need to do. */
15001 if (TREE_CODE (arg1) == REFERENCE_TYPE)
15003 arg1 = TREE_TYPE (arg1);
15004 quals1 = cp_type_quals (arg1);
15007 if (TREE_CODE (arg2) == REFERENCE_TYPE)
15009 arg2 = TREE_TYPE (arg2);
15010 quals2 = cp_type_quals (arg2);
15013 if ((quals1 < 0) != (quals2 < 0))
15015 /* Only of the args is a reference, see if we should apply
15016 array/function pointer decay to it. This is not part of
15017 DR214, but is, IMHO, consistent with the deduction rules
15018 for the function call itself, and with our earlier
15019 implementation of the underspecified partial ordering
15020 rules. (nathan). */
15023 switch (TREE_CODE (arg1))
15026 arg1 = TREE_TYPE (arg1);
15028 case FUNCTION_TYPE:
15029 arg1 = build_pointer_type (arg1);
15038 switch (TREE_CODE (arg2))
15041 arg2 = TREE_TYPE (arg2);
15043 case FUNCTION_TYPE:
15044 arg2 = build_pointer_type (arg2);
15053 arg1 = TYPE_MAIN_VARIANT (arg1);
15054 arg2 = TYPE_MAIN_VARIANT (arg2);
15056 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
15058 int i, len2 = list_length (args2);
15059 tree parmvec = make_tree_vec (1);
15060 tree argvec = make_tree_vec (len2);
15063 /* Setup the parameter vector, which contains only ARG1. */
15064 TREE_VEC_ELT (parmvec, 0) = arg1;
15066 /* Setup the argument vector, which contains the remaining
15068 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
15069 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
15071 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
15072 argvec, UNIFY_ALLOW_NONE,
15073 /*call_args_p=*/false,
15076 /* We cannot deduce in the other direction, because ARG1 is
15077 a pack expansion but ARG2 is not. */
15080 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15082 int i, len1 = list_length (args1);
15083 tree parmvec = make_tree_vec (1);
15084 tree argvec = make_tree_vec (len1);
15087 /* Setup the parameter vector, which contains only ARG1. */
15088 TREE_VEC_ELT (parmvec, 0) = arg2;
15090 /* Setup the argument vector, which contains the remaining
15092 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
15093 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
15095 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
15096 argvec, UNIFY_ALLOW_NONE,
15097 /*call_args_p=*/false,
15100 /* We cannot deduce in the other direction, because ARG2 is
15101 a pack expansion but ARG1 is not.*/
15107 /* The normal case, where neither argument is a pack
15109 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
15110 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
15113 /* If we couldn't deduce arguments for tparms1 to make arg1 match
15114 arg2, then arg2 is not as specialized as arg1. */
15120 /* "If, for a given type, deduction succeeds in both directions
15121 (i.e., the types are identical after the transformations above)
15122 and if the type from the argument template is more cv-qualified
15123 than the type from the parameter template (as described above)
15124 that type is considered to be more specialized than the other. If
15125 neither type is more cv-qualified than the other then neither type
15126 is more specialized than the other."
15128 We check same_type_p explicitly because deduction can also succeed
15129 in both directions when there is a nondeduced context. */
15130 if (deduce1 && deduce2
15131 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0
15132 && same_type_p (arg1, arg2))
15134 if ((quals1 & quals2) == quals2)
15136 if ((quals1 & quals2) == quals1)
15140 if (lose1 && lose2)
15141 /* We've failed to deduce something in either direction.
15142 These must be unordered. */
15145 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
15146 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
15147 /* We have already processed all of the arguments in our
15148 handing of the pack expansion type. */
15151 args1 = TREE_CHAIN (args1);
15152 args2 = TREE_CHAIN (args2);
15155 /* "In most cases, all template parameters must have values in order for
15156 deduction to succeed, but for partial ordering purposes a template
15157 parameter may remain without a value provided it is not used in the
15158 types being used for partial ordering."
15160 Thus, if we are missing any of the targs1 we need to substitute into
15161 origs1, then pat2 is not as specialized as pat1. This can happen when
15162 there is a nondeduced context. */
15163 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
15165 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
15168 processing_template_decl--;
15170 /* All things being equal, if the next argument is a pack expansion
15171 for one function but not for the other, prefer the
15172 non-variadic function. FIXME this is bogus; see c++/41958. */
15174 && args1 && TREE_VALUE (args1)
15175 && args2 && TREE_VALUE (args2))
15177 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
15178 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
15181 if (lose1 == lose2)
15189 /* Determine which of two partial specializations is more specialized.
15191 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
15192 to the first partial specialization. The TREE_VALUE is the
15193 innermost set of template parameters for the partial
15194 specialization. PAT2 is similar, but for the second template.
15196 Return 1 if the first partial specialization is more specialized;
15197 -1 if the second is more specialized; 0 if neither is more
15200 See [temp.class.order] for information about determining which of
15201 two templates is more specialized. */
15204 more_specialized_class (tree pat1, tree pat2)
15209 bool any_deductions = false;
15211 tmpl1 = TREE_TYPE (pat1);
15212 tmpl2 = TREE_TYPE (pat2);
15214 /* Just like what happens for functions, if we are ordering between
15215 different class template specializations, we may encounter dependent
15216 types in the arguments, and we need our dependency check functions
15217 to behave correctly. */
15218 ++processing_template_decl;
15219 targs = get_class_bindings (TREE_VALUE (pat1),
15220 CLASSTYPE_TI_ARGS (tmpl1),
15221 CLASSTYPE_TI_ARGS (tmpl2));
15225 any_deductions = true;
15228 targs = get_class_bindings (TREE_VALUE (pat2),
15229 CLASSTYPE_TI_ARGS (tmpl2),
15230 CLASSTYPE_TI_ARGS (tmpl1));
15234 any_deductions = true;
15236 --processing_template_decl;
15238 /* In the case of a tie where at least one of the class templates
15239 has a parameter pack at the end, the template with the most
15240 non-packed parameters wins. */
15243 && (template_args_variadic_p (TREE_PURPOSE (pat1))
15244 || template_args_variadic_p (TREE_PURPOSE (pat2))))
15246 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
15247 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
15248 int len1 = TREE_VEC_LENGTH (args1);
15249 int len2 = TREE_VEC_LENGTH (args2);
15251 /* We don't count the pack expansion at the end. */
15252 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
15254 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
15259 else if (len1 < len2)
15266 /* Return the template arguments that will produce the function signature
15267 DECL from the function template FN, with the explicit template
15268 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
15269 also match. Return NULL_TREE if no satisfactory arguments could be
15273 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
15275 int ntparms = DECL_NTPARMS (fn);
15276 tree targs = make_tree_vec (ntparms);
15278 tree decl_arg_types;
15280 unsigned int nargs, ix;
15283 /* Substitute the explicit template arguments into the type of DECL.
15284 The call to fn_type_unification will handle substitution into the
15286 decl_type = TREE_TYPE (decl);
15287 if (explicit_args && uses_template_parms (decl_type))
15290 tree converted_args;
15292 if (DECL_TEMPLATE_INFO (decl))
15293 tmpl = DECL_TI_TEMPLATE (decl);
15295 /* We can get here for some invalid specializations. */
15299 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
15300 explicit_args, NULL_TREE,
15302 /*require_all_args=*/false,
15303 /*use_default_args=*/false);
15304 if (converted_args == error_mark_node)
15307 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
15308 if (decl_type == error_mark_node)
15312 /* Never do unification on the 'this' parameter. */
15313 decl_arg_types = skip_artificial_parms_for (decl,
15314 TYPE_ARG_TYPES (decl_type));
15316 nargs = list_length (decl_arg_types);
15317 args = XALLOCAVEC (tree, nargs);
15318 for (arg = decl_arg_types, ix = 0;
15319 arg != NULL_TREE && arg != void_list_node;
15320 arg = TREE_CHAIN (arg), ++ix)
15321 args[ix] = TREE_VALUE (arg);
15323 if (fn_type_unification (fn, explicit_args, targs,
15325 (check_rettype || DECL_CONV_FN_P (fn)
15326 ? TREE_TYPE (decl_type) : NULL_TREE),
15327 DEDUCE_EXACT, LOOKUP_NORMAL))
15333 /* Return the innermost template arguments that, when applied to a
15334 template specialization whose innermost template parameters are
15335 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
15338 For example, suppose we have:
15340 template <class T, class U> struct S {};
15341 template <class T> struct S<T*, int> {};
15343 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
15344 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
15345 int}. The resulting vector will be {double}, indicating that `T'
15346 is bound to `double'. */
15349 get_class_bindings (tree tparms, tree spec_args, tree args)
15351 int i, ntparms = TREE_VEC_LENGTH (tparms);
15353 tree innermost_deduced_args;
15355 innermost_deduced_args = make_tree_vec (ntparms);
15356 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15358 deduced_args = copy_node (args);
15359 SET_TMPL_ARGS_LEVEL (deduced_args,
15360 TMPL_ARGS_DEPTH (deduced_args),
15361 innermost_deduced_args);
15364 deduced_args = innermost_deduced_args;
15366 if (unify (tparms, deduced_args,
15367 INNERMOST_TEMPLATE_ARGS (spec_args),
15368 INNERMOST_TEMPLATE_ARGS (args),
15372 for (i = 0; i < ntparms; ++i)
15373 if (! TREE_VEC_ELT (innermost_deduced_args, i))
15376 /* Verify that nondeduced template arguments agree with the type
15377 obtained from argument deduction.
15381 struct A { typedef int X; };
15382 template <class T, class U> struct C {};
15383 template <class T> struct C<T, typename T::X> {};
15385 Then with the instantiation `C<A, int>', we can deduce that
15386 `T' is `A' but unify () does not check whether `typename T::X'
15388 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
15389 if (spec_args == error_mark_node
15390 /* We only need to check the innermost arguments; the other
15391 arguments will always agree. */
15392 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
15393 INNERMOST_TEMPLATE_ARGS (args)))
15396 /* Now that we have bindings for all of the template arguments,
15397 ensure that the arguments deduced for the template template
15398 parameters have compatible template parameter lists. See the use
15399 of template_template_parm_bindings_ok_p in fn_type_unification
15400 for more information. */
15401 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
15404 return deduced_args;
15407 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
15408 Return the TREE_LIST node with the most specialized template, if
15409 any. If there is no most specialized template, the error_mark_node
15412 Note that this function does not look at, or modify, the
15413 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
15414 returned is one of the elements of INSTANTIATIONS, callers may
15415 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
15416 and retrieve it from the value returned. */
15419 most_specialized_instantiation (tree templates)
15423 ++processing_template_decl;
15426 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
15430 if (get_bindings (TREE_VALUE (champ),
15431 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
15432 NULL_TREE, /*check_ret=*/false))
15435 if (get_bindings (TREE_VALUE (fn),
15436 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
15437 NULL_TREE, /*check_ret=*/false))
15444 /* Equally specialized, move to next function. If there
15445 is no next function, nothing's most specialized. */
15446 fn = TREE_CHAIN (fn);
15454 /* Now verify that champ is better than everything earlier in the
15455 instantiation list. */
15456 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
15457 if (get_bindings (TREE_VALUE (champ),
15458 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
15459 NULL_TREE, /*check_ret=*/false)
15460 || !get_bindings (TREE_VALUE (fn),
15461 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
15462 NULL_TREE, /*check_ret=*/false))
15468 processing_template_decl--;
15471 return error_mark_node;
15476 /* If DECL is a specialization of some template, return the most
15477 general such template. Otherwise, returns NULL_TREE.
15479 For example, given:
15481 template <class T> struct S { template <class U> void f(U); };
15483 if TMPL is `template <class U> void S<int>::f(U)' this will return
15484 the full template. This function will not trace past partial
15485 specializations, however. For example, given in addition:
15487 template <class T> struct S<T*> { template <class U> void f(U); };
15489 if TMPL is `template <class U> void S<int*>::f(U)' this will return
15490 `template <class T> template <class U> S<T*>::f(U)'. */
15493 most_general_template (tree decl)
15495 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
15496 an immediate specialization. */
15497 if (TREE_CODE (decl) == FUNCTION_DECL)
15499 if (DECL_TEMPLATE_INFO (decl)) {
15500 decl = DECL_TI_TEMPLATE (decl);
15502 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
15503 template friend. */
15504 if (TREE_CODE (decl) != TEMPLATE_DECL)
15510 /* Look for more and more general templates. */
15511 while (DECL_TEMPLATE_INFO (decl))
15513 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
15514 (See cp-tree.h for details.) */
15515 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
15518 if (CLASS_TYPE_P (TREE_TYPE (decl))
15519 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
15522 /* Stop if we run into an explicitly specialized class template. */
15523 if (!DECL_NAMESPACE_SCOPE_P (decl)
15524 && DECL_CONTEXT (decl)
15525 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
15528 decl = DECL_TI_TEMPLATE (decl);
15534 /* Return the most specialized of the class template partial
15535 specializations of TMPL which can produce TYPE, a specialization of
15536 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
15537 a _TYPE node corresponding to the partial specialization, while the
15538 TREE_PURPOSE is the set of template arguments that must be
15539 substituted into the TREE_TYPE in order to generate TYPE.
15541 If the choice of partial specialization is ambiguous, a diagnostic
15542 is issued, and the error_mark_node is returned. If there are no
15543 partial specializations of TMPL matching TYPE, then NULL_TREE is
15547 most_specialized_class (tree type, tree tmpl)
15549 tree list = NULL_TREE;
15555 tree outer_args = NULL_TREE;
15557 tmpl = most_general_template (tmpl);
15558 args = CLASSTYPE_TI_ARGS (type);
15560 /* For determining which partial specialization to use, only the
15561 innermost args are interesting. */
15562 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15564 outer_args = strip_innermost_template_args (args, 1);
15565 args = INNERMOST_TEMPLATE_ARGS (args);
15568 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
15570 tree partial_spec_args;
15572 tree parms = TREE_VALUE (t);
15574 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
15579 ++processing_template_decl;
15581 /* Discard the outer levels of args, and then substitute in the
15582 template args from the enclosing class. */
15583 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
15584 partial_spec_args = tsubst_template_args
15585 (partial_spec_args, outer_args, tf_none, NULL_TREE);
15587 /* PARMS already refers to just the innermost parms, but the
15588 template parms in partial_spec_args had their levels lowered
15589 by tsubst, so we need to do the same for the parm list. We
15590 can't just tsubst the TREE_VEC itself, as tsubst wants to
15591 treat a TREE_VEC as an argument vector. */
15592 parms = copy_node (parms);
15593 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
15594 TREE_VEC_ELT (parms, i) =
15595 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
15597 --processing_template_decl;
15599 spec_args = get_class_bindings (parms,
15605 spec_args = add_to_template_args (outer_args, spec_args);
15606 list = tree_cons (spec_args, TREE_VALUE (t), list);
15607 TREE_TYPE (list) = TREE_TYPE (t);
15614 ambiguous_p = false;
15617 t = TREE_CHAIN (t);
15618 for (; t; t = TREE_CHAIN (t))
15620 fate = more_specialized_class (champ, t);
15627 t = TREE_CHAIN (t);
15630 ambiguous_p = true;
15639 for (t = list; t && t != champ; t = TREE_CHAIN (t))
15641 fate = more_specialized_class (champ, t);
15644 ambiguous_p = true;
15651 const char *str = "candidates are:";
15652 error ("ambiguous class template instantiation for %q#T", type);
15653 for (t = list; t; t = TREE_CHAIN (t))
15655 error ("%s %+#T", str, TREE_TYPE (t));
15658 return error_mark_node;
15664 /* Explicitly instantiate DECL. */
15667 do_decl_instantiation (tree decl, tree storage)
15669 tree result = NULL_TREE;
15672 if (!decl || decl == error_mark_node)
15673 /* An error occurred, for which grokdeclarator has already issued
15674 an appropriate message. */
15676 else if (! DECL_LANG_SPECIFIC (decl))
15678 error ("explicit instantiation of non-template %q#D", decl);
15681 else if (TREE_CODE (decl) == VAR_DECL)
15683 /* There is an asymmetry here in the way VAR_DECLs and
15684 FUNCTION_DECLs are handled by grokdeclarator. In the case of
15685 the latter, the DECL we get back will be marked as a
15686 template instantiation, and the appropriate
15687 DECL_TEMPLATE_INFO will be set up. This does not happen for
15688 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
15689 should handle VAR_DECLs as it currently handles
15691 if (!DECL_CLASS_SCOPE_P (decl))
15693 error ("%qD is not a static data member of a class template", decl);
15696 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
15697 if (!result || TREE_CODE (result) != VAR_DECL)
15699 error ("no matching template for %qD found", decl);
15702 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
15704 error ("type %qT for explicit instantiation %qD does not match "
15705 "declared type %qT", TREE_TYPE (result), decl,
15710 else if (TREE_CODE (decl) != FUNCTION_DECL)
15712 error ("explicit instantiation of %q#D", decl);
15718 /* Check for various error cases. Note that if the explicit
15719 instantiation is valid the RESULT will currently be marked as an
15720 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
15721 until we get here. */
15723 if (DECL_TEMPLATE_SPECIALIZATION (result))
15725 /* DR 259 [temp.spec].
15727 Both an explicit instantiation and a declaration of an explicit
15728 specialization shall not appear in a program unless the explicit
15729 instantiation follows a declaration of the explicit specialization.
15731 For a given set of template parameters, if an explicit
15732 instantiation of a template appears after a declaration of an
15733 explicit specialization for that template, the explicit
15734 instantiation has no effect. */
15737 else if (DECL_EXPLICIT_INSTANTIATION (result))
15741 No program shall explicitly instantiate any template more
15744 We check DECL_NOT_REALLY_EXTERN so as not to complain when
15745 the first instantiation was `extern' and the second is not,
15746 and EXTERN_P for the opposite case. */
15747 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
15748 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
15749 /* If an "extern" explicit instantiation follows an ordinary
15750 explicit instantiation, the template is instantiated. */
15754 else if (!DECL_IMPLICIT_INSTANTIATION (result))
15756 error ("no matching template for %qD found", result);
15759 else if (!DECL_TEMPLATE_INFO (result))
15761 permerror (input_location, "explicit instantiation of non-template %q#D", result);
15765 if (storage == NULL_TREE)
15767 else if (storage == ridpointers[(int) RID_EXTERN])
15769 if (!in_system_header && (cxx_dialect == cxx98))
15770 pedwarn (input_location, OPT_pedantic,
15771 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
15776 error ("storage class %qD applied to template instantiation", storage);
15778 check_explicit_instantiation_namespace (result);
15779 mark_decl_instantiated (result, extern_p);
15781 instantiate_decl (result, /*defer_ok=*/1,
15782 /*expl_inst_class_mem_p=*/false);
15786 mark_class_instantiated (tree t, int extern_p)
15788 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
15789 SET_CLASSTYPE_INTERFACE_KNOWN (t);
15790 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
15791 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
15794 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
15795 rest_of_type_compilation (t, 1);
15799 /* Called from do_type_instantiation through binding_table_foreach to
15800 do recursive instantiation for the type bound in ENTRY. */
15802 bt_instantiate_type_proc (binding_entry entry, void *data)
15804 tree storage = *(tree *) data;
15806 if (MAYBE_CLASS_TYPE_P (entry->type)
15807 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
15808 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
15811 /* Called from do_type_instantiation to instantiate a member
15812 (a member function or a static member variable) of an
15813 explicitly instantiated class template. */
15815 instantiate_class_member (tree decl, int extern_p)
15817 mark_decl_instantiated (decl, extern_p);
15819 instantiate_decl (decl, /*defer_ok=*/1,
15820 /*expl_inst_class_mem_p=*/true);
15823 /* Perform an explicit instantiation of template class T. STORAGE, if
15824 non-null, is the RID for extern, inline or static. COMPLAIN is
15825 nonzero if this is called from the parser, zero if called recursively,
15826 since the standard is unclear (as detailed below). */
15829 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
15834 int previous_instantiation_extern_p = 0;
15836 if (TREE_CODE (t) == TYPE_DECL)
15839 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
15841 error ("explicit instantiation of non-template type %qT", t);
15847 if (!COMPLETE_TYPE_P (t))
15849 if (complain & tf_error)
15850 error ("explicit instantiation of %q#T before definition of template",
15855 if (storage != NULL_TREE)
15857 if (!in_system_header)
15859 if (storage == ridpointers[(int) RID_EXTERN])
15861 if (cxx_dialect == cxx98)
15862 pedwarn (input_location, OPT_pedantic,
15863 "ISO C++ 1998 forbids the use of %<extern%> on "
15864 "explicit instantiations");
15867 pedwarn (input_location, OPT_pedantic,
15868 "ISO C++ forbids the use of %qE"
15869 " on explicit instantiations", storage);
15872 if (storage == ridpointers[(int) RID_INLINE])
15874 else if (storage == ridpointers[(int) RID_EXTERN])
15876 else if (storage == ridpointers[(int) RID_STATIC])
15880 error ("storage class %qD applied to template instantiation",
15886 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
15888 /* DR 259 [temp.spec].
15890 Both an explicit instantiation and a declaration of an explicit
15891 specialization shall not appear in a program unless the explicit
15892 instantiation follows a declaration of the explicit specialization.
15894 For a given set of template parameters, if an explicit
15895 instantiation of a template appears after a declaration of an
15896 explicit specialization for that template, the explicit
15897 instantiation has no effect. */
15900 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
15904 No program shall explicitly instantiate any template more
15907 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
15908 instantiation was `extern'. If EXTERN_P then the second is.
15909 These cases are OK. */
15910 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
15912 if (!previous_instantiation_extern_p && !extern_p
15913 && (complain & tf_error))
15914 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
15916 /* If we've already instantiated the template, just return now. */
15917 if (!CLASSTYPE_INTERFACE_ONLY (t))
15921 check_explicit_instantiation_namespace (TYPE_NAME (t));
15922 mark_class_instantiated (t, extern_p);
15930 /* In contrast to implicit instantiation, where only the
15931 declarations, and not the definitions, of members are
15932 instantiated, we have here:
15936 The explicit instantiation of a class template specialization
15937 implies the instantiation of all of its members not
15938 previously explicitly specialized in the translation unit
15939 containing the explicit instantiation.
15941 Of course, we can't instantiate member template classes, since
15942 we don't have any arguments for them. Note that the standard
15943 is unclear on whether the instantiation of the members are
15944 *explicit* instantiations or not. However, the most natural
15945 interpretation is that it should be an explicit instantiation. */
15948 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
15949 if (TREE_CODE (tmp) == FUNCTION_DECL
15950 && DECL_TEMPLATE_INSTANTIATION (tmp))
15951 instantiate_class_member (tmp, extern_p);
15953 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
15954 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
15955 instantiate_class_member (tmp, extern_p);
15957 if (CLASSTYPE_NESTED_UTDS (t))
15958 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
15959 bt_instantiate_type_proc, &storage);
15963 /* Given a function DECL, which is a specialization of TMPL, modify
15964 DECL to be a re-instantiation of TMPL with the same template
15965 arguments. TMPL should be the template into which tsubst'ing
15966 should occur for DECL, not the most general template.
15968 One reason for doing this is a scenario like this:
15971 void f(const T&, int i);
15973 void g() { f(3, 7); }
15976 void f(const T& t, const int i) { }
15978 Note that when the template is first instantiated, with
15979 instantiate_template, the resulting DECL will have no name for the
15980 first parameter, and the wrong type for the second. So, when we go
15981 to instantiate the DECL, we regenerate it. */
15984 regenerate_decl_from_template (tree decl, tree tmpl)
15986 /* The arguments used to instantiate DECL, from the most general
15991 args = DECL_TI_ARGS (decl);
15992 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
15994 /* Make sure that we can see identifiers, and compute access
15996 push_access_scope (decl);
15998 if (TREE_CODE (decl) == FUNCTION_DECL)
16006 args_depth = TMPL_ARGS_DEPTH (args);
16007 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
16008 if (args_depth > parms_depth)
16009 args = get_innermost_template_args (args, parms_depth);
16011 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
16012 args, tf_error, NULL_TREE);
16014 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
16017 /* Merge parameter declarations. */
16018 decl_parm = skip_artificial_parms_for (decl,
16019 DECL_ARGUMENTS (decl));
16021 = skip_artificial_parms_for (code_pattern,
16022 DECL_ARGUMENTS (code_pattern));
16023 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
16028 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
16029 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
16030 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
16032 parm_type = type_decays_to (parm_type);
16033 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
16034 TREE_TYPE (decl_parm) = parm_type;
16035 attributes = DECL_ATTRIBUTES (pattern_parm);
16036 if (DECL_ATTRIBUTES (decl_parm) != attributes)
16038 DECL_ATTRIBUTES (decl_parm) = attributes;
16039 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
16041 decl_parm = TREE_CHAIN (decl_parm);
16042 pattern_parm = TREE_CHAIN (pattern_parm);
16044 /* Merge any parameters that match with the function parameter
16046 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
16049 tree expanded_types;
16050 /* Expand the TYPE_PACK_EXPANSION that provides the types for
16051 the parameters in this function parameter pack. */
16052 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
16053 args, tf_error, NULL_TREE);
16054 len = TREE_VEC_LENGTH (expanded_types);
16055 for (i = 0; i < len; i++)
16060 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
16061 /* Rename the parameter to include the index. */
16062 DECL_NAME (decl_parm) =
16063 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
16064 parm_type = TREE_VEC_ELT (expanded_types, i);
16065 parm_type = type_decays_to (parm_type);
16066 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
16067 TREE_TYPE (decl_parm) = parm_type;
16068 attributes = DECL_ATTRIBUTES (pattern_parm);
16069 if (DECL_ATTRIBUTES (decl_parm) != attributes)
16071 DECL_ATTRIBUTES (decl_parm) = attributes;
16072 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
16074 decl_parm = TREE_CHAIN (decl_parm);
16077 /* Merge additional specifiers from the CODE_PATTERN. */
16078 if (DECL_DECLARED_INLINE_P (code_pattern)
16079 && !DECL_DECLARED_INLINE_P (decl))
16080 DECL_DECLARED_INLINE_P (decl) = 1;
16082 else if (TREE_CODE (decl) == VAR_DECL)
16083 DECL_INITIAL (decl) =
16084 tsubst_expr (DECL_INITIAL (code_pattern), args,
16085 tf_error, DECL_TI_TEMPLATE (decl),
16086 /*integral_constant_expression_p=*/false);
16088 gcc_unreachable ();
16090 pop_access_scope (decl);
16093 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
16094 substituted to get DECL. */
16097 template_for_substitution (tree decl)
16099 tree tmpl = DECL_TI_TEMPLATE (decl);
16101 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
16102 for the instantiation. This is not always the most general
16103 template. Consider, for example:
16106 struct S { template <class U> void f();
16107 template <> void f<int>(); };
16109 and an instantiation of S<double>::f<int>. We want TD to be the
16110 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
16111 while (/* An instantiation cannot have a definition, so we need a
16112 more general template. */
16113 DECL_TEMPLATE_INSTANTIATION (tmpl)
16114 /* We must also deal with friend templates. Given:
16116 template <class T> struct S {
16117 template <class U> friend void f() {};
16120 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
16121 so far as the language is concerned, but that's still
16122 where we get the pattern for the instantiation from. On
16123 other hand, if the definition comes outside the class, say:
16125 template <class T> struct S {
16126 template <class U> friend void f();
16128 template <class U> friend void f() {}
16130 we don't need to look any further. That's what the check for
16131 DECL_INITIAL is for. */
16132 || (TREE_CODE (decl) == FUNCTION_DECL
16133 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
16134 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
16136 /* The present template, TD, should not be a definition. If it
16137 were a definition, we should be using it! Note that we
16138 cannot restructure the loop to just keep going until we find
16139 a template with a definition, since that might go too far if
16140 a specialization was declared, but not defined. */
16141 gcc_assert (TREE_CODE (decl) != VAR_DECL
16142 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
16144 /* Fetch the more general template. */
16145 tmpl = DECL_TI_TEMPLATE (tmpl);
16151 /* Returns true if we need to instantiate this template instance even if we
16152 know we aren't going to emit it.. */
16155 always_instantiate_p (tree decl)
16157 /* We always instantiate inline functions so that we can inline them. An
16158 explicit instantiation declaration prohibits implicit instantiation of
16159 non-inline functions. With high levels of optimization, we would
16160 normally inline non-inline functions -- but we're not allowed to do
16161 that for "extern template" functions. Therefore, we check
16162 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
16163 return ((TREE_CODE (decl) == FUNCTION_DECL
16164 && DECL_DECLARED_INLINE_P (decl))
16165 /* And we need to instantiate static data members so that
16166 their initializers are available in integral constant
16168 || (TREE_CODE (decl) == VAR_DECL
16169 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)));
16172 /* Produce the definition of D, a _DECL generated from a template. If
16173 DEFER_OK is nonzero, then we don't have to actually do the
16174 instantiation now; we just have to do it sometime. Normally it is
16175 an error if this is an explicit instantiation but D is undefined.
16176 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
16177 explicitly instantiated class template. */
16180 instantiate_decl (tree d, int defer_ok,
16181 bool expl_inst_class_mem_p)
16183 tree tmpl = DECL_TI_TEMPLATE (d);
16190 bool pattern_defined;
16192 location_t saved_loc = input_location;
16195 /* This function should only be used to instantiate templates for
16196 functions and static member variables. */
16197 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
16198 || TREE_CODE (d) == VAR_DECL);
16200 /* Variables are never deferred; if instantiation is required, they
16201 are instantiated right away. That allows for better code in the
16202 case that an expression refers to the value of the variable --
16203 if the variable has a constant value the referring expression can
16204 take advantage of that fact. */
16205 if (TREE_CODE (d) == VAR_DECL)
16208 /* Don't instantiate cloned functions. Instead, instantiate the
16209 functions they cloned. */
16210 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
16211 d = DECL_CLONED_FUNCTION (d);
16213 if (DECL_TEMPLATE_INSTANTIATED (d)
16214 || DECL_TEMPLATE_SPECIALIZATION (d))
16215 /* D has already been instantiated or explicitly specialized, so
16216 there's nothing for us to do here.
16218 It might seem reasonable to check whether or not D is an explicit
16219 instantiation, and, if so, stop here. But when an explicit
16220 instantiation is deferred until the end of the compilation,
16221 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
16222 the instantiation. */
16225 /* Check to see whether we know that this template will be
16226 instantiated in some other file, as with "extern template"
16228 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
16230 /* In general, we do not instantiate such templates. */
16231 if (external_p && !always_instantiate_p (d))
16234 gen_tmpl = most_general_template (tmpl);
16235 gen_args = DECL_TI_ARGS (d);
16237 if (tmpl != gen_tmpl)
16238 /* We should already have the extra args. */
16239 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
16240 == TMPL_ARGS_DEPTH (gen_args));
16241 /* And what's in the hash table should match D. */
16242 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
16243 || spec == NULL_TREE);
16245 /* This needs to happen before any tsubsting. */
16246 if (! push_tinst_level (d))
16249 timevar_push (TV_PARSE);
16251 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
16252 for the instantiation. */
16253 td = template_for_substitution (d);
16254 code_pattern = DECL_TEMPLATE_RESULT (td);
16256 /* We should never be trying to instantiate a member of a class
16257 template or partial specialization. */
16258 gcc_assert (d != code_pattern);
16260 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
16261 || DECL_TEMPLATE_SPECIALIZATION (td))
16262 /* In the case of a friend template whose definition is provided
16263 outside the class, we may have too many arguments. Drop the
16264 ones we don't need. The same is true for specializations. */
16265 args = get_innermost_template_args
16266 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
16270 if (TREE_CODE (d) == FUNCTION_DECL)
16271 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
16273 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
16275 /* We may be in the middle of deferred access check. Disable it now. */
16276 push_deferring_access_checks (dk_no_deferred);
16278 /* Unless an explicit instantiation directive has already determined
16279 the linkage of D, remember that a definition is available for
16281 if (pattern_defined
16282 && !DECL_INTERFACE_KNOWN (d)
16283 && !DECL_NOT_REALLY_EXTERN (d))
16284 mark_definable (d);
16286 input_location = DECL_SOURCE_LOCATION (d);
16288 /* If D is a member of an explicitly instantiated class template,
16289 and no definition is available, treat it like an implicit
16291 if (!pattern_defined && expl_inst_class_mem_p
16292 && DECL_EXPLICIT_INSTANTIATION (d))
16294 DECL_NOT_REALLY_EXTERN (d) = 0;
16295 DECL_INTERFACE_KNOWN (d) = 0;
16296 SET_DECL_IMPLICIT_INSTANTIATION (d);
16299 /* Recheck the substitutions to obtain any warning messages
16300 about ignoring cv qualifiers. Don't do this for artificial decls,
16301 as it breaks the context-sensitive substitution for lambda op(). */
16302 if (!defer_ok && !DECL_ARTIFICIAL (d))
16304 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
16305 tree type = TREE_TYPE (gen);
16307 /* Make sure that we can see identifiers, and compute access
16308 correctly. D is already the target FUNCTION_DECL with the
16310 push_access_scope (d);
16312 if (TREE_CODE (gen) == FUNCTION_DECL)
16314 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
16315 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
16317 /* Don't simply tsubst the function type, as that will give
16318 duplicate warnings about poor parameter qualifications.
16319 The function arguments are the same as the decl_arguments
16320 without the top level cv qualifiers. */
16321 type = TREE_TYPE (type);
16323 tsubst (type, gen_args, tf_warning_or_error, d);
16325 pop_access_scope (d);
16328 /* Defer all other templates, unless we have been explicitly
16329 forbidden from doing so. */
16330 if (/* If there is no definition, we cannot instantiate the
16333 /* If it's OK to postpone instantiation, do so. */
16335 /* If this is a static data member that will be defined
16336 elsewhere, we don't want to instantiate the entire data
16337 member, but we do want to instantiate the initializer so that
16338 we can substitute that elsewhere. */
16339 || (external_p && TREE_CODE (d) == VAR_DECL))
16341 /* The definition of the static data member is now required so
16342 we must substitute the initializer. */
16343 if (TREE_CODE (d) == VAR_DECL
16344 && !DECL_INITIAL (d)
16345 && DECL_INITIAL (code_pattern))
16350 ns = decl_namespace_context (d);
16351 push_nested_namespace (ns);
16352 push_nested_class (DECL_CONTEXT (d));
16353 init = tsubst_expr (DECL_INITIAL (code_pattern),
16355 tf_warning_or_error, NULL_TREE,
16356 /*integral_constant_expression_p=*/false);
16357 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
16358 /*asmspec_tree=*/NULL_TREE,
16359 LOOKUP_ONLYCONVERTING);
16360 pop_nested_class ();
16361 pop_nested_namespace (ns);
16364 /* We restore the source position here because it's used by
16365 add_pending_template. */
16366 input_location = saved_loc;
16368 if (at_eof && !pattern_defined
16369 && DECL_EXPLICIT_INSTANTIATION (d)
16370 && DECL_NOT_REALLY_EXTERN (d))
16373 The definition of a non-exported function template, a
16374 non-exported member function template, or a non-exported
16375 member function or static data member of a class template
16376 shall be present in every translation unit in which it is
16377 explicitly instantiated. */
16378 permerror (input_location, "explicit instantiation of %qD "
16379 "but no definition available", d);
16381 /* ??? Historically, we have instantiated inline functions, even
16382 when marked as "extern template". */
16383 if (!(external_p && TREE_CODE (d) == VAR_DECL))
16384 add_pending_template (d);
16387 /* Tell the repository that D is available in this translation unit
16388 -- and see if it is supposed to be instantiated here. */
16389 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
16391 /* In a PCH file, despite the fact that the repository hasn't
16392 requested instantiation in the PCH it is still possible that
16393 an instantiation will be required in a file that includes the
16396 add_pending_template (d);
16397 /* Instantiate inline functions so that the inliner can do its
16398 job, even though we'll not be emitting a copy of this
16400 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
16404 need_push = !cfun || !global_bindings_p ();
16406 push_to_top_level ();
16408 /* Mark D as instantiated so that recursive calls to
16409 instantiate_decl do not try to instantiate it again. */
16410 DECL_TEMPLATE_INSTANTIATED (d) = 1;
16412 /* Regenerate the declaration in case the template has been modified
16413 by a subsequent redeclaration. */
16414 regenerate_decl_from_template (d, td);
16416 /* We already set the file and line above. Reset them now in case
16417 they changed as a result of calling regenerate_decl_from_template. */
16418 input_location = DECL_SOURCE_LOCATION (d);
16420 if (TREE_CODE (d) == VAR_DECL)
16424 /* Clear out DECL_RTL; whatever was there before may not be right
16425 since we've reset the type of the declaration. */
16426 SET_DECL_RTL (d, NULL_RTX);
16427 DECL_IN_AGGR_P (d) = 0;
16429 /* The initializer is placed in DECL_INITIAL by
16430 regenerate_decl_from_template. Pull it out so that
16431 cp_finish_decl can process it. */
16432 init = DECL_INITIAL (d);
16433 DECL_INITIAL (d) = NULL_TREE;
16434 DECL_INITIALIZED_P (d) = 0;
16436 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
16437 initializer. That function will defer actual emission until
16438 we have a chance to determine linkage. */
16439 DECL_EXTERNAL (d) = 0;
16441 /* Enter the scope of D so that access-checking works correctly. */
16442 push_nested_class (DECL_CONTEXT (d));
16443 cp_finish_decl (d, init, false, NULL_TREE, 0);
16444 pop_nested_class ();
16446 else if (TREE_CODE (d) == FUNCTION_DECL)
16448 htab_t saved_local_specializations;
16453 /* Save away the current list, in case we are instantiating one
16454 template from within the body of another. */
16455 saved_local_specializations = local_specializations;
16457 /* Set up the list of local specializations. */
16458 local_specializations = htab_create (37,
16459 hash_local_specialization,
16460 eq_local_specializations,
16463 /* Set up context. */
16464 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
16466 /* Create substitution entries for the parameters. */
16467 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
16468 tmpl_parm = DECL_ARGUMENTS (subst_decl);
16469 spec_parm = DECL_ARGUMENTS (d);
16470 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
16472 register_local_specialization (spec_parm, tmpl_parm);
16473 spec_parm = skip_artificial_parms_for (d, spec_parm);
16474 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
16476 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
16478 register_local_specialization (spec_parm, tmpl_parm);
16479 tmpl_parm = TREE_CHAIN (tmpl_parm);
16480 spec_parm = TREE_CHAIN (spec_parm);
16482 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
16484 /* Register the (value) argument pack as a specialization of
16485 TMPL_PARM, then move on. */
16486 tree argpack = make_fnparm_pack (spec_parm);
16487 register_local_specialization (argpack, tmpl_parm);
16488 tmpl_parm = TREE_CHAIN (tmpl_parm);
16489 spec_parm = NULL_TREE;
16491 gcc_assert (!spec_parm);
16493 /* Substitute into the body of the function. */
16494 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
16495 tf_warning_or_error, tmpl,
16496 /*integral_constant_expression_p=*/false);
16498 /* Set the current input_location to the end of the function
16499 so that finish_function knows where we are. */
16500 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
16502 /* We don't need the local specializations any more. */
16503 htab_delete (local_specializations);
16504 local_specializations = saved_local_specializations;
16506 /* Finish the function. */
16507 d = finish_function (0);
16508 expand_or_defer_fn (d);
16511 /* We're not deferring instantiation any more. */
16512 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
16515 pop_from_top_level ();
16518 input_location = saved_loc;
16519 pop_deferring_access_checks ();
16520 pop_tinst_level ();
16522 timevar_pop (TV_PARSE);
16527 /* Run through the list of templates that we wish we could
16528 instantiate, and instantiate any we can. RETRIES is the
16529 number of times we retry pending template instantiation. */
16532 instantiate_pending_templates (int retries)
16535 location_t saved_loc = input_location;
16537 /* Instantiating templates may trigger vtable generation. This in turn
16538 may require further template instantiations. We place a limit here
16539 to avoid infinite loop. */
16540 if (pending_templates && retries >= max_tinst_depth)
16542 tree decl = pending_templates->tinst->decl;
16544 error ("template instantiation depth exceeds maximum of %d"
16545 " instantiating %q+D, possibly from virtual table generation"
16546 " (use -ftemplate-depth-NN to increase the maximum)",
16547 max_tinst_depth, decl);
16548 if (TREE_CODE (decl) == FUNCTION_DECL)
16549 /* Pretend that we defined it. */
16550 DECL_INITIAL (decl) = error_mark_node;
16556 struct pending_template **t = &pending_templates;
16557 struct pending_template *last = NULL;
16561 tree instantiation = reopen_tinst_level ((*t)->tinst);
16562 bool complete = false;
16564 if (TYPE_P (instantiation))
16568 if (!COMPLETE_TYPE_P (instantiation))
16570 instantiate_class_template (instantiation);
16571 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
16572 for (fn = TYPE_METHODS (instantiation);
16574 fn = TREE_CHAIN (fn))
16575 if (! DECL_ARTIFICIAL (fn))
16576 instantiate_decl (fn,
16578 /*expl_inst_class_mem_p=*/false);
16579 if (COMPLETE_TYPE_P (instantiation))
16583 complete = COMPLETE_TYPE_P (instantiation);
16587 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
16588 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
16591 = instantiate_decl (instantiation,
16593 /*expl_inst_class_mem_p=*/false);
16594 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
16598 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
16599 || DECL_TEMPLATE_INSTANTIATED (instantiation));
16603 /* If INSTANTIATION has been instantiated, then we don't
16604 need to consider it again in the future. */
16612 current_tinst_level = NULL;
16614 last_pending_template = last;
16616 while (reconsider);
16618 input_location = saved_loc;
16621 /* Substitute ARGVEC into T, which is a list of initializers for
16622 either base class or a non-static data member. The TREE_PURPOSEs
16623 are DECLs, and the TREE_VALUEs are the initializer values. Used by
16624 instantiate_decl. */
16627 tsubst_initializer_list (tree t, tree argvec)
16629 tree inits = NULL_TREE;
16631 for (; t; t = TREE_CHAIN (t))
16635 tree expanded_bases = NULL_TREE;
16636 tree expanded_arguments = NULL_TREE;
16639 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
16644 /* Expand the base class expansion type into separate base
16646 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
16647 tf_warning_or_error,
16649 if (expanded_bases == error_mark_node)
16652 /* We'll be building separate TREE_LISTs of arguments for
16654 len = TREE_VEC_LENGTH (expanded_bases);
16655 expanded_arguments = make_tree_vec (len);
16656 for (i = 0; i < len; i++)
16657 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
16659 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
16660 expand each argument in the TREE_VALUE of t. */
16661 expr = make_node (EXPR_PACK_EXPANSION);
16662 PACK_EXPANSION_PARAMETER_PACKS (expr) =
16663 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
16665 if (TREE_VALUE (t) == void_type_node)
16666 /* VOID_TYPE_NODE is used to indicate
16667 value-initialization. */
16669 for (i = 0; i < len; i++)
16670 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
16674 /* Substitute parameter packs into each argument in the
16676 in_base_initializer = 1;
16677 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
16679 tree expanded_exprs;
16681 /* Expand the argument. */
16682 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
16684 = tsubst_pack_expansion (expr, argvec,
16685 tf_warning_or_error,
16687 if (expanded_exprs == error_mark_node)
16690 /* Prepend each of the expanded expressions to the
16691 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
16692 for (i = 0; i < len; i++)
16694 TREE_VEC_ELT (expanded_arguments, i) =
16695 tree_cons (NULL_TREE,
16696 TREE_VEC_ELT (expanded_exprs, i),
16697 TREE_VEC_ELT (expanded_arguments, i));
16700 in_base_initializer = 0;
16702 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
16703 since we built them backwards. */
16704 for (i = 0; i < len; i++)
16706 TREE_VEC_ELT (expanded_arguments, i) =
16707 nreverse (TREE_VEC_ELT (expanded_arguments, i));
16712 for (i = 0; i < len; ++i)
16714 if (expanded_bases)
16716 decl = TREE_VEC_ELT (expanded_bases, i);
16717 decl = expand_member_init (decl);
16718 init = TREE_VEC_ELT (expanded_arguments, i);
16722 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
16723 tf_warning_or_error, NULL_TREE);
16725 decl = expand_member_init (decl);
16726 if (decl && !DECL_P (decl))
16727 in_base_initializer = 1;
16729 init = tsubst_expr (TREE_VALUE (t), argvec,
16730 tf_warning_or_error, NULL_TREE,
16731 /*integral_constant_expression_p=*/false);
16732 in_base_initializer = 0;
16737 init = build_tree_list (decl, init);
16738 TREE_CHAIN (init) = inits;
16746 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
16749 set_current_access_from_decl (tree decl)
16751 if (TREE_PRIVATE (decl))
16752 current_access_specifier = access_private_node;
16753 else if (TREE_PROTECTED (decl))
16754 current_access_specifier = access_protected_node;
16756 current_access_specifier = access_public_node;
16759 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
16760 is the instantiation (which should have been created with
16761 start_enum) and ARGS are the template arguments to use. */
16764 tsubst_enum (tree tag, tree newtag, tree args)
16768 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
16773 decl = TREE_VALUE (e);
16774 /* Note that in a template enum, the TREE_VALUE is the
16775 CONST_DECL, not the corresponding INTEGER_CST. */
16776 value = tsubst_expr (DECL_INITIAL (decl),
16777 args, tf_warning_or_error, NULL_TREE,
16778 /*integral_constant_expression_p=*/true);
16780 /* Give this enumeration constant the correct access. */
16781 set_current_access_from_decl (decl);
16783 /* Actually build the enumerator itself. */
16784 build_enumerator (DECL_NAME (decl), value, newtag);
16787 finish_enum (newtag);
16788 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
16789 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
16792 /* DECL is a FUNCTION_DECL that is a template specialization. Return
16793 its type -- but without substituting the innermost set of template
16794 arguments. So, innermost set of template parameters will appear in
16798 get_mostly_instantiated_function_type (tree decl)
16806 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
16807 targs = DECL_TI_ARGS (decl);
16808 tparms = DECL_TEMPLATE_PARMS (tmpl);
16809 parm_depth = TMPL_PARMS_DEPTH (tparms);
16811 /* There should be as many levels of arguments as there are levels
16813 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
16815 fn_type = TREE_TYPE (tmpl);
16817 if (parm_depth == 1)
16818 /* No substitution is necessary. */
16822 int i, save_access_control;
16825 /* Replace the innermost level of the TARGS with NULL_TREEs to
16826 let tsubst know not to substitute for those parameters. */
16827 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
16828 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
16829 SET_TMPL_ARGS_LEVEL (partial_args, i,
16830 TMPL_ARGS_LEVEL (targs, i));
16831 SET_TMPL_ARGS_LEVEL (partial_args,
16832 TMPL_ARGS_DEPTH (targs),
16833 make_tree_vec (DECL_NTPARMS (tmpl)));
16835 /* Disable access control as this function is used only during
16837 save_access_control = flag_access_control;
16838 flag_access_control = 0;
16840 ++processing_template_decl;
16841 /* Now, do the (partial) substitution to figure out the
16842 appropriate function type. */
16843 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
16844 --processing_template_decl;
16846 /* Substitute into the template parameters to obtain the real
16847 innermost set of parameters. This step is important if the
16848 innermost set of template parameters contains value
16849 parameters whose types depend on outer template parameters. */
16850 TREE_VEC_LENGTH (partial_args)--;
16851 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
16853 flag_access_control = save_access_control;
16859 /* Return truthvalue if we're processing a template different from
16860 the last one involved in diagnostics. */
16862 problematic_instantiation_changed (void)
16864 return last_template_error_tick != tinst_level_tick;
16867 /* Remember current template involved in diagnostics. */
16869 record_last_problematic_instantiation (void)
16871 last_template_error_tick = tinst_level_tick;
16874 struct tinst_level *
16875 current_instantiation (void)
16877 return current_tinst_level;
16880 /* [temp.param] Check that template non-type parm TYPE is of an allowable
16881 type. Return zero for ok, nonzero for disallowed. Issue error and
16882 warning messages under control of COMPLAIN. */
16885 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
16887 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
16889 else if (POINTER_TYPE_P (type))
16891 else if (TYPE_PTR_TO_MEMBER_P (type))
16893 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
16895 else if (TREE_CODE (type) == TYPENAME_TYPE)
16898 if (complain & tf_error)
16899 error ("%q#T is not a valid type for a template constant parameter", type);
16903 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
16904 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
16907 dependent_type_p_r (tree type)
16913 A type is dependent if it is:
16915 -- a template parameter. Template template parameters are types
16916 for us (since TYPE_P holds true for them) so we handle
16918 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
16919 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
16921 /* -- a qualified-id with a nested-name-specifier which contains a
16922 class-name that names a dependent type or whose unqualified-id
16923 names a dependent type. */
16924 if (TREE_CODE (type) == TYPENAME_TYPE)
16926 /* -- a cv-qualified type where the cv-unqualified type is
16928 type = TYPE_MAIN_VARIANT (type);
16929 /* -- a compound type constructed from any dependent type. */
16930 if (TYPE_PTR_TO_MEMBER_P (type))
16931 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
16932 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
16934 else if (TREE_CODE (type) == POINTER_TYPE
16935 || TREE_CODE (type) == REFERENCE_TYPE)
16936 return dependent_type_p (TREE_TYPE (type));
16937 else if (TREE_CODE (type) == FUNCTION_TYPE
16938 || TREE_CODE (type) == METHOD_TYPE)
16942 if (dependent_type_p (TREE_TYPE (type)))
16944 for (arg_type = TYPE_ARG_TYPES (type);
16946 arg_type = TREE_CHAIN (arg_type))
16947 if (dependent_type_p (TREE_VALUE (arg_type)))
16951 /* -- an array type constructed from any dependent type or whose
16952 size is specified by a constant expression that is
16953 value-dependent. */
16954 if (TREE_CODE (type) == ARRAY_TYPE)
16956 if (TYPE_DOMAIN (type)
16957 && dependent_type_p (TYPE_DOMAIN (type)))
16959 return dependent_type_p (TREE_TYPE (type));
16961 else if (TREE_CODE (type) == INTEGER_TYPE
16962 && !TREE_CONSTANT (TYPE_MAX_VALUE (type)))
16964 /* If this is the TYPE_DOMAIN of an array type, consider it
16965 dependent. We already checked for value-dependence in
16966 compute_array_index_type. */
16967 return type_dependent_expression_p (TYPE_MAX_VALUE (type));
16970 /* -- a template-id in which either the template name is a template
16972 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
16974 /* ... or any of the template arguments is a dependent type or
16975 an expression that is type-dependent or value-dependent. */
16976 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
16977 && (any_dependent_template_arguments_p
16978 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
16981 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
16982 argument of the `typeof' expression is not type-dependent, then
16983 it should already been have resolved. */
16984 if (TREE_CODE (type) == TYPEOF_TYPE
16985 || TREE_CODE (type) == DECLTYPE_TYPE)
16988 /* A template argument pack is dependent if any of its packed
16990 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
16992 tree args = ARGUMENT_PACK_ARGS (type);
16993 int i, len = TREE_VEC_LENGTH (args);
16994 for (i = 0; i < len; ++i)
16995 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
16999 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
17000 be template parameters. */
17001 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
17004 /* The standard does not specifically mention types that are local
17005 to template functions or local classes, but they should be
17006 considered dependent too. For example:
17008 template <int I> void f() {
17013 The size of `E' cannot be known until the value of `I' has been
17014 determined. Therefore, `E' must be considered dependent. */
17015 scope = TYPE_CONTEXT (type);
17016 if (scope && TYPE_P (scope))
17017 return dependent_type_p (scope);
17018 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
17019 return type_dependent_expression_p (scope);
17021 /* Other types are non-dependent. */
17025 /* Returns TRUE if TYPE is dependent, in the sense of
17026 [temp.dep.type]. */
17029 dependent_type_p (tree type)
17031 /* If there are no template parameters in scope, then there can't be
17032 any dependent types. */
17033 if (!processing_template_decl)
17035 /* If we are not processing a template, then nobody should be
17036 providing us with a dependent type. */
17038 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
17042 /* If the type is NULL, we have not computed a type for the entity
17043 in question; in that case, the type is dependent. */
17047 /* Erroneous types can be considered non-dependent. */
17048 if (type == error_mark_node)
17051 /* If we have not already computed the appropriate value for TYPE,
17053 if (!TYPE_DEPENDENT_P_VALID (type))
17055 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
17056 TYPE_DEPENDENT_P_VALID (type) = 1;
17059 return TYPE_DEPENDENT_P (type);
17062 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
17063 lookup. In other words, a dependent type that is not the current
17067 dependent_scope_p (tree scope)
17069 return (scope && TYPE_P (scope) && dependent_type_p (scope)
17070 && !currently_open_class (scope));
17073 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
17076 dependent_scope_ref_p (tree expression, bool criterion (tree))
17081 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
17083 if (!TYPE_P (TREE_OPERAND (expression, 0)))
17086 scope = TREE_OPERAND (expression, 0);
17087 name = TREE_OPERAND (expression, 1);
17091 An id-expression is type-dependent if it contains a
17092 nested-name-specifier that contains a class-name that names a
17094 /* The suggested resolution to Core Issue 224 implies that if the
17095 qualifying type is the current class, then we must peek
17098 && currently_open_class (scope)
17099 && !criterion (name))
17101 if (dependent_type_p (scope))
17107 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
17108 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
17112 value_dependent_expression_p (tree expression)
17114 if (!processing_template_decl)
17117 /* A name declared with a dependent type. */
17118 if (DECL_P (expression) && type_dependent_expression_p (expression))
17121 switch (TREE_CODE (expression))
17123 case IDENTIFIER_NODE:
17124 /* A name that has not been looked up -- must be dependent. */
17127 case TEMPLATE_PARM_INDEX:
17128 /* A non-type template parm. */
17132 /* A non-type template parm. */
17133 if (DECL_TEMPLATE_PARM_P (expression))
17135 return value_dependent_expression_p (DECL_INITIAL (expression));
17138 /* A constant with integral or enumeration type and is initialized
17139 with an expression that is value-dependent. */
17140 if (DECL_INITIAL (expression)
17141 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
17142 && value_dependent_expression_p (DECL_INITIAL (expression)))
17146 case DYNAMIC_CAST_EXPR:
17147 case STATIC_CAST_EXPR:
17148 case CONST_CAST_EXPR:
17149 case REINTERPRET_CAST_EXPR:
17151 /* These expressions are value-dependent if the type to which
17152 the cast occurs is dependent or the expression being casted
17153 is value-dependent. */
17155 tree type = TREE_TYPE (expression);
17157 if (dependent_type_p (type))
17160 /* A functional cast has a list of operands. */
17161 expression = TREE_OPERAND (expression, 0);
17164 /* If there are no operands, it must be an expression such
17165 as "int()". This should not happen for aggregate types
17166 because it would form non-constant expressions. */
17167 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
17172 if (TREE_CODE (expression) == TREE_LIST)
17173 return any_value_dependent_elements_p (expression);
17175 return value_dependent_expression_p (expression);
17180 /* A `sizeof' expression is value-dependent if the operand is
17181 type-dependent or is a pack expansion. */
17182 expression = TREE_OPERAND (expression, 0);
17183 if (PACK_EXPANSION_P (expression))
17185 else if (TYPE_P (expression))
17186 return dependent_type_p (expression);
17187 return type_dependent_expression_p (expression);
17190 return dependent_scope_ref_p (expression, value_dependent_expression_p);
17192 case COMPONENT_REF:
17193 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
17194 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
17197 /* A CALL_EXPR may appear in a constant expression if it is a
17198 call to a builtin function, e.g., __builtin_constant_p. All
17199 such calls are value-dependent. */
17202 case NONTYPE_ARGUMENT_PACK:
17203 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
17204 is value-dependent. */
17206 tree values = ARGUMENT_PACK_ARGS (expression);
17207 int i, len = TREE_VEC_LENGTH (values);
17209 for (i = 0; i < len; ++i)
17210 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
17218 tree type2 = TRAIT_EXPR_TYPE2 (expression);
17219 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
17220 || (type2 ? dependent_type_p (type2) : false));
17224 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
17225 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
17228 /* A constant expression is value-dependent if any subexpression is
17229 value-dependent. */
17230 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
17232 case tcc_reference:
17234 return (value_dependent_expression_p
17235 (TREE_OPERAND (expression, 0)));
17237 case tcc_comparison:
17239 return ((value_dependent_expression_p
17240 (TREE_OPERAND (expression, 0)))
17241 || (value_dependent_expression_p
17242 (TREE_OPERAND (expression, 1))));
17244 case tcc_expression:
17248 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
17249 /* In some cases, some of the operands may be missing.
17250 (For example, in the case of PREDECREMENT_EXPR, the
17251 amount to increment by may be missing.) That doesn't
17252 make the expression dependent. */
17253 if (TREE_OPERAND (expression, i)
17254 && (value_dependent_expression_p
17255 (TREE_OPERAND (expression, i))))
17265 /* The expression is not value-dependent. */
17269 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
17270 [temp.dep.expr]. */
17273 type_dependent_expression_p (tree expression)
17275 if (!processing_template_decl)
17278 if (expression == error_mark_node)
17281 /* An unresolved name is always dependent. */
17282 if (TREE_CODE (expression) == IDENTIFIER_NODE
17283 || TREE_CODE (expression) == USING_DECL)
17286 /* Some expression forms are never type-dependent. */
17287 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
17288 || TREE_CODE (expression) == SIZEOF_EXPR
17289 || TREE_CODE (expression) == ALIGNOF_EXPR
17290 || TREE_CODE (expression) == TRAIT_EXPR
17291 || TREE_CODE (expression) == TYPEID_EXPR
17292 || TREE_CODE (expression) == DELETE_EXPR
17293 || TREE_CODE (expression) == VEC_DELETE_EXPR
17294 || TREE_CODE (expression) == THROW_EXPR)
17297 /* The types of these expressions depends only on the type to which
17298 the cast occurs. */
17299 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
17300 || TREE_CODE (expression) == STATIC_CAST_EXPR
17301 || TREE_CODE (expression) == CONST_CAST_EXPR
17302 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
17303 || TREE_CODE (expression) == CAST_EXPR)
17304 return dependent_type_p (TREE_TYPE (expression));
17306 /* The types of these expressions depends only on the type created
17307 by the expression. */
17308 if (TREE_CODE (expression) == NEW_EXPR
17309 || TREE_CODE (expression) == VEC_NEW_EXPR)
17311 /* For NEW_EXPR tree nodes created inside a template, either
17312 the object type itself or a TREE_LIST may appear as the
17314 tree type = TREE_OPERAND (expression, 1);
17315 if (TREE_CODE (type) == TREE_LIST)
17316 /* This is an array type. We need to check array dimensions
17318 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
17319 || value_dependent_expression_p
17320 (TREE_OPERAND (TREE_VALUE (type), 1));
17322 return dependent_type_p (type);
17325 if (TREE_CODE (expression) == SCOPE_REF
17326 && dependent_scope_ref_p (expression,
17327 type_dependent_expression_p))
17330 if (TREE_CODE (expression) == FUNCTION_DECL
17331 && DECL_LANG_SPECIFIC (expression)
17332 && DECL_TEMPLATE_INFO (expression)
17333 && (any_dependent_template_arguments_p
17334 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
17337 if (TREE_CODE (expression) == TEMPLATE_DECL
17338 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
17341 if (TREE_CODE (expression) == STMT_EXPR)
17342 expression = stmt_expr_value_expr (expression);
17344 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
17349 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
17351 if (type_dependent_expression_p (elt))
17357 if (TREE_TYPE (expression) == unknown_type_node)
17359 if (TREE_CODE (expression) == ADDR_EXPR)
17360 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
17361 if (TREE_CODE (expression) == COMPONENT_REF
17362 || TREE_CODE (expression) == OFFSET_REF)
17364 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
17366 expression = TREE_OPERAND (expression, 1);
17367 if (TREE_CODE (expression) == IDENTIFIER_NODE)
17370 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
17371 if (TREE_CODE (expression) == SCOPE_REF)
17374 if (TREE_CODE (expression) == BASELINK)
17375 expression = BASELINK_FUNCTIONS (expression);
17377 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
17379 if (any_dependent_template_arguments_p
17380 (TREE_OPERAND (expression, 1)))
17382 expression = TREE_OPERAND (expression, 0);
17384 gcc_assert (TREE_CODE (expression) == OVERLOAD
17385 || TREE_CODE (expression) == FUNCTION_DECL);
17389 if (type_dependent_expression_p (OVL_CURRENT (expression)))
17391 expression = OVL_NEXT (expression);
17396 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
17398 return (dependent_type_p (TREE_TYPE (expression)));
17401 /* Like type_dependent_expression_p, but it also works while not processing
17402 a template definition, i.e. during substitution or mangling. */
17405 type_dependent_expression_p_push (tree expr)
17408 ++processing_template_decl;
17409 b = type_dependent_expression_p (expr);
17410 --processing_template_decl;
17414 /* Returns TRUE if ARGS contains a type-dependent expression. */
17417 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
17422 for (i = 0; VEC_iterate (tree, args, i, arg); ++i)
17424 if (type_dependent_expression_p (arg))
17430 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
17431 expressions) contains any value-dependent expressions. */
17434 any_value_dependent_elements_p (const_tree list)
17436 for (; list; list = TREE_CHAIN (list))
17437 if (value_dependent_expression_p (TREE_VALUE (list)))
17443 /* Returns TRUE if the ARG (a template argument) is dependent. */
17446 dependent_template_arg_p (tree arg)
17448 if (!processing_template_decl)
17451 if (TREE_CODE (arg) == TEMPLATE_DECL
17452 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
17453 return dependent_template_p (arg);
17454 else if (ARGUMENT_PACK_P (arg))
17456 tree args = ARGUMENT_PACK_ARGS (arg);
17457 int i, len = TREE_VEC_LENGTH (args);
17458 for (i = 0; i < len; ++i)
17460 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
17466 else if (TYPE_P (arg))
17467 return dependent_type_p (arg);
17469 return (type_dependent_expression_p (arg)
17470 || value_dependent_expression_p (arg));
17473 /* Returns true if ARGS (a collection of template arguments) contains
17474 any types that require structural equality testing. */
17477 any_template_arguments_need_structural_equality_p (tree args)
17484 if (args == error_mark_node)
17487 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17489 tree level = TMPL_ARGS_LEVEL (args, i + 1);
17490 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17492 tree arg = TREE_VEC_ELT (level, j);
17493 tree packed_args = NULL_TREE;
17496 if (ARGUMENT_PACK_P (arg))
17498 /* Look inside the argument pack. */
17499 packed_args = ARGUMENT_PACK_ARGS (arg);
17500 len = TREE_VEC_LENGTH (packed_args);
17503 for (k = 0; k < len; ++k)
17506 arg = TREE_VEC_ELT (packed_args, k);
17508 if (error_operand_p (arg))
17510 else if (TREE_CODE (arg) == TEMPLATE_DECL
17511 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
17513 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
17515 else if (!TYPE_P (arg) && TREE_TYPE (arg)
17516 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
17525 /* Returns true if ARGS (a collection of template arguments) contains
17526 any dependent arguments. */
17529 any_dependent_template_arguments_p (const_tree args)
17536 if (args == error_mark_node)
17539 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17541 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
17542 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17543 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
17550 /* Returns TRUE if the template TMPL is dependent. */
17553 dependent_template_p (tree tmpl)
17555 if (TREE_CODE (tmpl) == OVERLOAD)
17559 if (dependent_template_p (OVL_FUNCTION (tmpl)))
17561 tmpl = OVL_CHAIN (tmpl);
17566 /* Template template parameters are dependent. */
17567 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
17568 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
17570 /* So are names that have not been looked up. */
17571 if (TREE_CODE (tmpl) == SCOPE_REF
17572 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
17574 /* So are member templates of dependent classes. */
17575 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
17576 return dependent_type_p (DECL_CONTEXT (tmpl));
17580 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
17583 dependent_template_id_p (tree tmpl, tree args)
17585 return (dependent_template_p (tmpl)
17586 || any_dependent_template_arguments_p (args));
17589 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
17593 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
17597 if (!processing_template_decl)
17600 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
17602 tree decl = TREE_VEC_ELT (declv, i);
17603 tree init = TREE_VEC_ELT (initv, i);
17604 tree cond = TREE_VEC_ELT (condv, i);
17605 tree incr = TREE_VEC_ELT (incrv, i);
17607 if (type_dependent_expression_p (decl))
17610 if (init && type_dependent_expression_p (init))
17613 if (type_dependent_expression_p (cond))
17616 if (COMPARISON_CLASS_P (cond)
17617 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
17618 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
17621 if (TREE_CODE (incr) == MODOP_EXPR)
17623 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
17624 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
17627 else if (type_dependent_expression_p (incr))
17629 else if (TREE_CODE (incr) == MODIFY_EXPR)
17631 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
17633 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
17635 tree t = TREE_OPERAND (incr, 1);
17636 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
17637 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
17646 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
17647 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
17648 no such TYPE can be found. Note that this function peers inside
17649 uninstantiated templates and therefore should be used only in
17650 extremely limited situations. ONLY_CURRENT_P restricts this
17651 peering to the currently open classes hierarchy (which is required
17652 when comparing types). */
17655 resolve_typename_type (tree type, bool only_current_p)
17664 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
17666 scope = TYPE_CONTEXT (type);
17667 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
17668 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
17669 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
17670 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
17671 identifier of the TYPENAME_TYPE anymore.
17672 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
17673 TYPENAME_TYPE instead, we avoid messing up with a possible
17674 typedef variant case. */
17675 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
17677 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
17678 it first before we can figure out what NAME refers to. */
17679 if (TREE_CODE (scope) == TYPENAME_TYPE)
17680 scope = resolve_typename_type (scope, only_current_p);
17681 /* If we don't know what SCOPE refers to, then we cannot resolve the
17683 if (TREE_CODE (scope) == TYPENAME_TYPE)
17685 /* If the SCOPE is a template type parameter, we have no way of
17686 resolving the name. */
17687 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
17689 /* If the SCOPE is not the current instantiation, there's no reason
17690 to look inside it. */
17691 if (only_current_p && !currently_open_class (scope))
17693 /* If SCOPE isn't the template itself, it will not have a valid
17694 TYPE_FIELDS list. */
17695 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
17696 /* scope is either the template itself or a compatible instantiation
17697 like X<T>, so look up the name in the original template. */
17698 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
17700 /* scope is a partial instantiation, so we can't do the lookup or we
17701 will lose the template arguments. */
17703 /* Enter the SCOPE so that name lookup will be resolved as if we
17704 were in the class definition. In particular, SCOPE will no
17705 longer be considered a dependent type. */
17706 pushed_scope = push_scope (scope);
17707 /* Look up the declaration. */
17708 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
17710 result = NULL_TREE;
17712 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
17713 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
17716 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
17717 && TREE_CODE (decl) == TYPE_DECL)
17719 result = TREE_TYPE (decl);
17720 if (result == error_mark_node)
17721 result = NULL_TREE;
17723 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
17724 && DECL_CLASS_TEMPLATE_P (decl))
17728 /* Obtain the template and the arguments. */
17729 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
17730 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
17731 /* Instantiate the template. */
17732 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
17733 /*entering_scope=*/0,
17734 tf_error | tf_user);
17735 if (result == error_mark_node)
17736 result = NULL_TREE;
17739 /* Leave the SCOPE. */
17741 pop_scope (pushed_scope);
17743 /* If we failed to resolve it, return the original typename. */
17747 /* If lookup found a typename type, resolve that too. */
17748 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
17750 /* Ill-formed programs can cause infinite recursion here, so we
17751 must catch that. */
17752 TYPENAME_IS_RESOLVING_P (type) = 1;
17753 result = resolve_typename_type (result, only_current_p);
17754 TYPENAME_IS_RESOLVING_P (type) = 0;
17757 /* Qualify the resulting type. */
17758 quals = cp_type_quals (type);
17760 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
17765 /* EXPR is an expression which is not type-dependent. Return a proxy
17766 for EXPR that can be used to compute the types of larger
17767 expressions containing EXPR. */
17770 build_non_dependent_expr (tree expr)
17774 /* Preserve null pointer constants so that the type of things like
17775 "p == 0" where "p" is a pointer can be determined. */
17776 if (null_ptr_cst_p (expr))
17778 /* Preserve OVERLOADs; the functions must be available to resolve
17781 if (TREE_CODE (inner_expr) == STMT_EXPR)
17782 inner_expr = stmt_expr_value_expr (inner_expr);
17783 if (TREE_CODE (inner_expr) == ADDR_EXPR)
17784 inner_expr = TREE_OPERAND (inner_expr, 0);
17785 if (TREE_CODE (inner_expr) == COMPONENT_REF)
17786 inner_expr = TREE_OPERAND (inner_expr, 1);
17787 if (is_overloaded_fn (inner_expr)
17788 || TREE_CODE (inner_expr) == OFFSET_REF)
17790 /* There is no need to return a proxy for a variable. */
17791 if (TREE_CODE (expr) == VAR_DECL)
17793 /* Preserve string constants; conversions from string constants to
17794 "char *" are allowed, even though normally a "const char *"
17795 cannot be used to initialize a "char *". */
17796 if (TREE_CODE (expr) == STRING_CST)
17798 /* Preserve arithmetic constants, as an optimization -- there is no
17799 reason to create a new node. */
17800 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
17802 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
17803 There is at least one place where we want to know that a
17804 particular expression is a throw-expression: when checking a ?:
17805 expression, there are special rules if the second or third
17806 argument is a throw-expression. */
17807 if (TREE_CODE (expr) == THROW_EXPR)
17810 if (TREE_CODE (expr) == COND_EXPR)
17811 return build3 (COND_EXPR,
17813 TREE_OPERAND (expr, 0),
17814 (TREE_OPERAND (expr, 1)
17815 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
17816 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
17817 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
17818 if (TREE_CODE (expr) == COMPOUND_EXPR
17819 && !COMPOUND_EXPR_OVERLOADED (expr))
17820 return build2 (COMPOUND_EXPR,
17822 TREE_OPERAND (expr, 0),
17823 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
17825 /* If the type is unknown, it can't really be non-dependent */
17826 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
17828 /* Otherwise, build a NON_DEPENDENT_EXPR.
17830 REFERENCE_TYPEs are not stripped for expressions in templates
17831 because doing so would play havoc with mangling. Consider, for
17834 template <typename T> void f<T& g>() { g(); }
17836 In the body of "f", the expression for "g" will have
17837 REFERENCE_TYPE, even though the standard says that it should
17838 not. The reason is that we must preserve the syntactic form of
17839 the expression so that mangling (say) "f<g>" inside the body of
17840 "f" works out correctly. Therefore, the REFERENCE_TYPE is
17842 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
17845 /* ARGS is a vector of expressions as arguments to a function call.
17846 Replace the arguments with equivalent non-dependent expressions.
17847 This modifies ARGS in place. */
17850 make_args_non_dependent (VEC(tree,gc) *args)
17855 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
17857 tree newarg = build_non_dependent_expr (arg);
17859 VEC_replace (tree, args, ix, newarg);
17863 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
17864 with a level one deeper than the actual template parms. */
17869 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
17870 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
17871 TYPE_DECL, get_identifier ("auto"), au);
17872 TYPE_STUB_DECL (au) = TYPE_NAME (au);
17873 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
17874 (0, processing_template_decl + 1, processing_template_decl + 1,
17875 TYPE_NAME (au), NULL_TREE);
17876 TYPE_CANONICAL (au) = canonical_type_parameter (au);
17877 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
17878 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
17883 /* Given type ARG, return std::initializer_list<ARG>. */
17888 tree std_init_list = namespace_binding
17889 (get_identifier ("initializer_list"), std_node);
17891 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
17893 error ("deducing from brace-enclosed initializer list requires "
17894 "#include <initializer_list>");
17895 return error_mark_node;
17897 argvec = make_tree_vec (1);
17898 TREE_VEC_ELT (argvec, 0) = arg;
17899 return lookup_template_class (std_init_list, argvec, NULL_TREE,
17900 NULL_TREE, 0, tf_warning_or_error);
17903 /* Replace auto in TYPE with std::initializer_list<auto>. */
17906 listify_autos (tree type, tree auto_node)
17908 tree init_auto = listify (auto_node);
17909 tree argvec = make_tree_vec (1);
17910 TREE_VEC_ELT (argvec, 0) = init_auto;
17911 if (processing_template_decl)
17912 argvec = add_to_template_args (current_template_args (), argvec);
17913 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
17916 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
17917 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
17920 do_auto_deduction (tree type, tree init, tree auto_node)
17922 tree parms, tparms, targs;
17926 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
17927 with either a new invented type template parameter U or, if the
17928 initializer is a braced-init-list (8.5.4), with
17929 std::initializer_list<U>. */
17930 if (BRACE_ENCLOSED_INITIALIZER_P (init))
17931 type = listify_autos (type, auto_node);
17933 parms = build_tree_list (NULL_TREE, type);
17935 tparms = make_tree_vec (1);
17936 targs = make_tree_vec (1);
17937 TREE_VEC_ELT (tparms, 0)
17938 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
17939 val = type_unification_real (tparms, targs, parms, args, 1, 0,
17940 DEDUCE_CALL, LOOKUP_NORMAL);
17943 error ("unable to deduce %qT from %qE", type, init);
17944 return error_mark_node;
17947 /* If the list of declarators contains more than one declarator, the type
17948 of each declared variable is determined as described above. If the
17949 type deduced for the template parameter U is not the same in each
17950 deduction, the program is ill-formed. */
17951 if (TREE_TYPE (auto_node)
17952 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
17954 error ("inconsistent deduction for %qT: %qT and then %qT",
17955 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
17956 return error_mark_node;
17958 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
17960 if (processing_template_decl)
17961 targs = add_to_template_args (current_template_args (), targs);
17962 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
17965 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
17969 splice_late_return_type (tree type, tree late_return_type)
17973 if (late_return_type == NULL_TREE)
17975 argvec = make_tree_vec (1);
17976 TREE_VEC_ELT (argvec, 0) = late_return_type;
17977 if (processing_template_decl)
17978 argvec = add_to_template_args (current_template_args (), argvec);
17979 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
17982 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
17985 is_auto (const_tree type)
17987 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
17988 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
17994 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
17995 appear as a type-specifier for the declaration in question, we don't
17996 have to look through the whole type. */
17999 type_uses_auto (tree type)
18001 enum tree_code code;
18002 if (is_auto (type))
18005 code = TREE_CODE (type);
18007 if (code == POINTER_TYPE || code == REFERENCE_TYPE
18008 || code == OFFSET_TYPE || code == FUNCTION_TYPE
18009 || code == METHOD_TYPE || code == ARRAY_TYPE)
18010 return type_uses_auto (TREE_TYPE (type));
18012 if (TYPE_PTRMEMFUNC_P (type))
18013 return type_uses_auto (TREE_TYPE (TREE_TYPE
18014 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
18019 /* For a given template T, return the list of typedefs referenced
18020 in T for which access check is needed at T instantiation time.
18021 T is either a FUNCTION_DECL or a RECORD_TYPE.
18022 Those typedefs were added to T by the function
18023 append_type_to_template_for_access_check. */
18026 get_types_needing_access_check (tree t)
18028 tree ti, result = NULL_TREE;
18030 if (!t || t == error_mark_node)
18033 if (!(ti = get_template_info (t)))
18036 if (CLASS_TYPE_P (t)
18037 || TREE_CODE (t) == FUNCTION_DECL)
18039 if (!TI_TEMPLATE (ti))
18042 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
18048 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
18049 tied to T. That list of typedefs will be access checked at
18050 T instantiation time.
18051 T is either a FUNCTION_DECL or a RECORD_TYPE.
18052 TYPE_DECL is a TYPE_DECL node representing a typedef.
18053 SCOPE is the scope through which TYPE_DECL is accessed.
18055 This function is a subroutine of
18056 append_type_to_template_for_access_check. */
18059 append_type_to_template_for_access_check_1 (tree t,
18065 if (!t || t == error_mark_node)
18068 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
18069 || CLASS_TYPE_P (t))
18071 && TREE_CODE (type_decl) == TYPE_DECL
18074 if (!(ti = get_template_info (t)))
18077 gcc_assert (TI_TEMPLATE (ti));
18079 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti) =
18080 tree_cons (type_decl, scope, TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti));
18083 /* Append TYPE_DECL to the template TEMPL.
18084 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
18085 At TEMPL instanciation time, TYPE_DECL will be checked to see
18086 if it can be accessed through SCOPE.
18088 e.g. consider the following code snippet:
18095 template<class U> struct S
18102 At S<char> instantiation time, we need to check the access of C::myint
18103 In other words, we need to check the access of the myint typedef through
18104 the C scope. For that purpose, this function will add the myint typedef
18105 and the scope C through which its being accessed to a list of typedefs
18106 tied to the template S. That list will be walked at template instantiation
18107 time and access check performed on each typedefs it contains.
18108 Note that this particular code snippet should yield an error because
18109 myint is private to C. */
18112 append_type_to_template_for_access_check (tree templ,
18118 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
18120 /* Make sure we don't append the type to the template twice. */
18121 for (node = get_types_needing_access_check (templ);
18123 node = TREE_CHAIN (node))
18125 tree decl = TREE_PURPOSE (node);
18126 tree type_scope = TREE_VALUE (node);
18128 if (decl == type_decl && type_scope == scope)
18132 append_type_to_template_for_access_check_1 (templ, type_decl, scope);
18135 /* Set up the hash tables for template instantiations. */
18138 init_template_processing (void)
18140 decl_specializations = htab_create_ggc (37,
18141 hash_specialization,
18142 eq_specializations,
18144 type_specializations = htab_create_ggc (37,
18145 hash_specialization,
18146 eq_specializations,
18150 #include "gt-cp-pt.h"