1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992-2013 Free Software Foundation, Inc.
3 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
4 Rewritten by Jason Merrill (jason@cygnus.com).
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* Known bugs or deficiencies include:
24 all methods must be provided in header files; can't use a source
25 file that contains only the method templates and "just win". */
29 #include "coretypes.h"
33 #include "pointer-set.h"
36 #include "c-family/c-common.h"
37 #include "c-family/c-objc.h"
38 #include "cp-objcp-common.h"
39 #include "tree-inline.h"
43 #include "tree-iterator.h"
45 /* The type of functions taking a tree, and some additional data, and
47 typedef int (*tree_fn_t) (tree, void*);
49 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
50 instantiations have been deferred, either because their definitions
51 were not yet available, or because we were putting off doing the work. */
52 struct GTY ((chain_next ("%h.next"))) pending_template {
53 struct pending_template *next;
54 struct tinst_level *tinst;
57 static GTY(()) struct pending_template *pending_templates;
58 static GTY(()) struct pending_template *last_pending_template;
60 int processing_template_parmlist;
61 static int template_header_count;
63 static GTY(()) tree saved_trees;
64 static vec<int> inline_parm_levels;
66 static GTY(()) struct tinst_level *current_tinst_level;
68 static GTY(()) tree saved_access_scope;
70 /* Live only within one (recursive) call to tsubst_expr. We use
71 this to pass the statement expression node from the STMT_EXPR
72 to the EXPR_STMT that is its result. */
73 static tree cur_stmt_expr;
75 /* A map from local variable declarations in the body of the template
76 presently being instantiated to the corresponding instantiated
78 static struct pointer_map_t *local_specializations;
80 /* True if we've recursed into fn_type_unification too many times. */
81 static bool excessive_deduction_depth;
83 typedef struct GTY(()) spec_entry
90 static GTY ((param_is (spec_entry)))
91 htab_t decl_specializations;
93 static GTY ((param_is (spec_entry)))
94 htab_t type_specializations;
96 /* Contains canonical template parameter types. The vector is indexed by
97 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
98 TREE_LIST, whose TREE_VALUEs contain the canonical template
99 parameters of various types and levels. */
100 static GTY(()) vec<tree, va_gc> *canonical_template_parms;
102 #define UNIFY_ALLOW_NONE 0
103 #define UNIFY_ALLOW_MORE_CV_QUAL 1
104 #define UNIFY_ALLOW_LESS_CV_QUAL 2
105 #define UNIFY_ALLOW_DERIVED 4
106 #define UNIFY_ALLOW_INTEGER 8
107 #define UNIFY_ALLOW_OUTER_LEVEL 16
108 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
109 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
111 enum template_base_result {
113 tbr_ambiguous_baseclass,
117 static void push_access_scope (tree);
118 static void pop_access_scope (tree);
119 static bool resolve_overloaded_unification (tree, tree, tree, tree,
120 unification_kind_t, int,
122 static int try_one_overload (tree, tree, tree, tree, tree,
123 unification_kind_t, int, bool, bool);
124 static int unify (tree, tree, tree, tree, int, bool);
125 static void add_pending_template (tree);
126 static tree reopen_tinst_level (struct tinst_level *);
127 static tree tsubst_initializer_list (tree, tree);
128 static tree get_class_bindings (tree, tree, tree, tree);
129 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
131 static tree coerce_innermost_template_parms (tree, tree, tree, tsubst_flags_t,
133 static void tsubst_enum (tree, tree, tree);
134 static tree add_to_template_args (tree, tree);
135 static tree add_outermost_template_args (tree, tree);
136 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
137 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
139 static int type_unification_real (tree, tree, tree, const tree *,
140 unsigned int, int, unification_kind_t, int,
141 vec<deferred_access_check, va_gc> **,
143 static void note_template_header (int);
144 static tree convert_nontype_argument_function (tree, tree);
145 static tree convert_nontype_argument (tree, tree, tsubst_flags_t);
146 static tree convert_template_argument (tree, tree, tree,
147 tsubst_flags_t, int, tree);
148 static int for_each_template_parm (tree, tree_fn_t, void*,
149 struct pointer_set_t*, bool);
150 static tree expand_template_argument_pack (tree);
151 static tree build_template_parm_index (int, int, int, tree, tree);
152 static bool inline_needs_template_parms (tree);
153 static void push_inline_template_parms_recursive (tree, int);
154 static tree retrieve_local_specialization (tree);
155 static void register_local_specialization (tree, tree);
156 static hashval_t hash_specialization (const void *p);
157 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
158 static int mark_template_parm (tree, void *);
159 static int template_parm_this_level_p (tree, void *);
160 static tree tsubst_friend_function (tree, tree);
161 static tree tsubst_friend_class (tree, tree);
162 static int can_complete_type_without_circularity (tree);
163 static tree get_bindings (tree, tree, tree, bool);
164 static int template_decl_level (tree);
165 static int check_cv_quals_for_unify (int, tree, tree);
166 static void template_parm_level_and_index (tree, int*, int*);
167 static int unify_pack_expansion (tree, tree, tree,
168 tree, unification_kind_t, bool, bool);
169 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
170 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
171 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
172 static void regenerate_decl_from_template (tree, tree);
173 static tree most_specialized_class (tree, tree, tsubst_flags_t);
174 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
175 static tree tsubst_arg_types (tree, tree, tree, tsubst_flags_t, tree);
176 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
177 static bool check_specialization_scope (void);
178 static tree process_partial_specialization (tree);
179 static void set_current_access_from_decl (tree);
180 static enum template_base_result get_template_base (tree, tree, tree, tree,
182 static tree try_class_unification (tree, tree, tree, tree, bool);
183 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
185 static bool template_template_parm_bindings_ok_p (tree, tree);
186 static int template_args_equal (tree, tree);
187 static void tsubst_default_arguments (tree, tsubst_flags_t);
188 static tree for_each_template_parm_r (tree *, int *, void *);
189 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
190 static void copy_default_args_to_explicit_spec (tree);
191 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
192 static bool dependent_template_arg_p (tree);
193 static bool any_template_arguments_need_structural_equality_p (tree);
194 static bool dependent_type_p_r (tree);
195 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
196 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
197 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
198 static tree tsubst_decl (tree, tree, tsubst_flags_t);
199 static void perform_typedefs_access_check (tree tmpl, tree targs);
200 static void append_type_to_template_for_access_check_1 (tree, tree, tree,
202 static tree listify (tree);
203 static tree listify_autos (tree, tree);
204 static tree template_parm_to_arg (tree t);
205 static tree current_template_args (void);
206 static tree tsubst_template_parm (tree, tree, tsubst_flags_t);
207 static tree instantiate_alias_template (tree, tree, tsubst_flags_t);
209 /* Make the current scope suitable for access checking when we are
210 processing T. T can be FUNCTION_DECL for instantiated function
211 template, VAR_DECL for static member variable, or TYPE_DECL for
212 alias template (needed by instantiate_decl). */
215 push_access_scope (tree t)
217 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
218 || TREE_CODE (t) == TYPE_DECL
219 || TREE_CODE (t) == VAR_DECL);
221 if (DECL_FRIEND_CONTEXT (t))
222 push_nested_class (DECL_FRIEND_CONTEXT (t));
223 else if (DECL_CLASS_SCOPE_P (t))
224 push_nested_class (DECL_CONTEXT (t));
226 push_to_top_level ();
228 if (TREE_CODE (t) == FUNCTION_DECL)
230 saved_access_scope = tree_cons
231 (NULL_TREE, current_function_decl, saved_access_scope);
232 current_function_decl = t;
236 /* Restore the scope set up by push_access_scope. T is the node we
240 pop_access_scope (tree t)
242 if (TREE_CODE (t) == FUNCTION_DECL)
244 current_function_decl = TREE_VALUE (saved_access_scope);
245 saved_access_scope = TREE_CHAIN (saved_access_scope);
248 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
251 pop_from_top_level ();
254 /* Do any processing required when DECL (a member template
255 declaration) is finished. Returns the TEMPLATE_DECL corresponding
256 to DECL, unless it is a specialization, in which case the DECL
257 itself is returned. */
260 finish_member_template_decl (tree decl)
262 if (decl == error_mark_node)
263 return error_mark_node;
265 gcc_assert (DECL_P (decl));
267 if (TREE_CODE (decl) == TYPE_DECL)
271 type = TREE_TYPE (decl);
272 if (type == error_mark_node)
273 return error_mark_node;
274 if (MAYBE_CLASS_TYPE_P (type)
275 && CLASSTYPE_TEMPLATE_INFO (type)
276 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
278 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
279 check_member_template (tmpl);
284 else if (TREE_CODE (decl) == FIELD_DECL)
285 error ("data member %qD cannot be a member template", decl);
286 else if (DECL_TEMPLATE_INFO (decl))
288 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
290 check_member_template (DECL_TI_TEMPLATE (decl));
291 return DECL_TI_TEMPLATE (decl);
297 error ("invalid member template declaration %qD", decl);
299 return error_mark_node;
302 /* Create a template info node. */
305 build_template_info (tree template_decl, tree template_args)
307 tree result = make_node (TEMPLATE_INFO);
308 TI_TEMPLATE (result) = template_decl;
309 TI_ARGS (result) = template_args;
313 /* Return the template info node corresponding to T, whatever T is. */
316 get_template_info (const_tree t)
318 tree tinfo = NULL_TREE;
320 if (!t || t == error_mark_node)
323 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
324 tinfo = DECL_TEMPLATE_INFO (t);
326 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t))
329 if (TAGGED_TYPE_P (t))
330 tinfo = TYPE_TEMPLATE_INFO (t);
331 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
332 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t);
337 /* Returns the template nesting level of the indicated class TYPE.
347 A<T>::B<U> has depth two, while A<T> has depth one.
348 Both A<T>::B<int> and A<int>::B<U> have depth one, if
349 they are instantiations, not specializations.
351 This function is guaranteed to return 0 if passed NULL_TREE so
352 that, for example, `template_class_depth (current_class_type)' is
356 template_class_depth (tree type)
361 type && TREE_CODE (type) != NAMESPACE_DECL;
362 type = (TREE_CODE (type) == FUNCTION_DECL)
363 ? CP_DECL_CONTEXT (type) : CP_TYPE_CONTEXT (type))
365 tree tinfo = get_template_info (type);
367 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
368 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
375 /* Subroutine of maybe_begin_member_template_processing.
376 Returns true if processing DECL needs us to push template parms. */
379 inline_needs_template_parms (tree decl)
381 if (! DECL_TEMPLATE_INFO (decl))
384 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
385 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
388 /* Subroutine of maybe_begin_member_template_processing.
389 Push the template parms in PARMS, starting from LEVELS steps into the
390 chain, and ending at the beginning, since template parms are listed
394 push_inline_template_parms_recursive (tree parmlist, int levels)
396 tree parms = TREE_VALUE (parmlist);
400 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
402 ++processing_template_decl;
403 current_template_parms
404 = tree_cons (size_int (processing_template_decl),
405 parms, current_template_parms);
406 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
408 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
410 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
412 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
414 if (parm == error_mark_node)
417 gcc_assert (DECL_P (parm));
419 switch (TREE_CODE (parm))
428 /* Make a CONST_DECL as is done in process_template_parm.
429 It is ugly that we recreate this here; the original
430 version built in process_template_parm is no longer
432 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
433 CONST_DECL, DECL_NAME (parm),
435 DECL_ARTIFICIAL (decl) = 1;
436 TREE_CONSTANT (decl) = 1;
437 TREE_READONLY (decl) = 1;
438 DECL_INITIAL (decl) = DECL_INITIAL (parm);
439 SET_DECL_TEMPLATE_PARM_P (decl);
450 /* Restore the template parameter context for a member template or
451 a friend template defined in a class definition. */
454 maybe_begin_member_template_processing (tree decl)
459 if (inline_needs_template_parms (decl))
461 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
462 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
464 if (DECL_TEMPLATE_SPECIALIZATION (decl))
467 parms = TREE_CHAIN (parms);
470 push_inline_template_parms_recursive (parms, levels);
473 /* Remember how many levels of template parameters we pushed so that
474 we can pop them later. */
475 inline_parm_levels.safe_push (levels);
478 /* Undo the effects of maybe_begin_member_template_processing. */
481 maybe_end_member_template_processing (void)
486 if (inline_parm_levels.length () == 0)
489 last = inline_parm_levels.pop ();
490 for (i = 0; i < last; ++i)
492 --processing_template_decl;
493 current_template_parms = TREE_CHAIN (current_template_parms);
498 /* Return a new template argument vector which contains all of ARGS,
499 but has as its innermost set of arguments the EXTRA_ARGS. */
502 add_to_template_args (tree args, tree extra_args)
509 if (args == NULL_TREE || extra_args == error_mark_node)
512 extra_depth = TMPL_ARGS_DEPTH (extra_args);
513 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
515 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
516 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
518 for (j = 1; j <= extra_depth; ++j, ++i)
519 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
524 /* Like add_to_template_args, but only the outermost ARGS are added to
525 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
526 (EXTRA_ARGS) levels are added. This function is used to combine
527 the template arguments from a partial instantiation with the
528 template arguments used to attain the full instantiation from the
529 partial instantiation. */
532 add_outermost_template_args (tree args, tree extra_args)
536 /* If there are more levels of EXTRA_ARGS than there are ARGS,
537 something very fishy is going on. */
538 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
540 /* If *all* the new arguments will be the EXTRA_ARGS, just return
542 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
545 /* For the moment, we make ARGS look like it contains fewer levels. */
546 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
548 new_args = add_to_template_args (args, extra_args);
550 /* Now, we restore ARGS to its full dimensions. */
551 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
556 /* Return the N levels of innermost template arguments from the ARGS. */
559 get_innermost_template_args (tree args, int n)
567 /* If N is 1, just return the innermost set of template arguments. */
569 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
571 /* If we're not removing anything, just return the arguments we were
573 extra_levels = TMPL_ARGS_DEPTH (args) - n;
574 gcc_assert (extra_levels >= 0);
575 if (extra_levels == 0)
578 /* Make a new set of arguments, not containing the outer arguments. */
579 new_args = make_tree_vec (n);
580 for (i = 1; i <= n; ++i)
581 SET_TMPL_ARGS_LEVEL (new_args, i,
582 TMPL_ARGS_LEVEL (args, i + extra_levels));
587 /* The inverse of get_innermost_template_args: Return all but the innermost
588 EXTRA_LEVELS levels of template arguments from the ARGS. */
591 strip_innermost_template_args (tree args, int extra_levels)
594 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
599 /* If N is 1, just return the outermost set of template arguments. */
601 return TMPL_ARGS_LEVEL (args, 1);
603 /* If we're not removing anything, just return the arguments we were
605 gcc_assert (extra_levels >= 0);
606 if (extra_levels == 0)
609 /* Make a new set of arguments, not containing the inner arguments. */
610 new_args = make_tree_vec (n);
611 for (i = 1; i <= n; ++i)
612 SET_TMPL_ARGS_LEVEL (new_args, i,
613 TMPL_ARGS_LEVEL (args, i));
618 /* We've got a template header coming up; push to a new level for storing
622 begin_template_parm_list (void)
624 /* We use a non-tag-transparent scope here, which causes pushtag to
625 put tags in this scope, rather than in the enclosing class or
626 namespace scope. This is the right thing, since we want
627 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
628 global template class, push_template_decl handles putting the
629 TEMPLATE_DECL into top-level scope. For a nested template class,
632 template <class T> struct S1 {
633 template <class T> struct S2 {};
636 pushtag contains special code to call pushdecl_with_scope on the
637 TEMPLATE_DECL for S2. */
638 begin_scope (sk_template_parms, NULL);
639 ++processing_template_decl;
640 ++processing_template_parmlist;
641 note_template_header (0);
644 /* This routine is called when a specialization is declared. If it is
645 invalid to declare a specialization here, an error is reported and
646 false is returned, otherwise this routine will return true. */
649 check_specialization_scope (void)
651 tree scope = current_scope ();
655 An explicit specialization shall be declared in the namespace of
656 which the template is a member, or, for member templates, in the
657 namespace of which the enclosing class or enclosing class
658 template is a member. An explicit specialization of a member
659 function, member class or static data member of a class template
660 shall be declared in the namespace of which the class template
662 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
664 error ("explicit specialization in non-namespace scope %qD", scope);
670 In an explicit specialization declaration for a member of a class
671 template or a member template that appears in namespace scope,
672 the member template and some of its enclosing class templates may
673 remain unspecialized, except that the declaration shall not
674 explicitly specialize a class member template if its enclosing
675 class templates are not explicitly specialized as well. */
676 if (current_template_parms)
678 error ("enclosing class templates are not explicitly specialized");
685 /* We've just seen template <>. */
688 begin_specialization (void)
690 begin_scope (sk_template_spec, NULL);
691 note_template_header (1);
692 return check_specialization_scope ();
695 /* Called at then end of processing a declaration preceded by
699 end_specialization (void)
702 reset_specialization ();
705 /* Any template <>'s that we have seen thus far are not referring to a
706 function specialization. */
709 reset_specialization (void)
711 processing_specialization = 0;
712 template_header_count = 0;
715 /* We've just seen a template header. If SPECIALIZATION is nonzero,
716 it was of the form template <>. */
719 note_template_header (int specialization)
721 processing_specialization = specialization;
722 template_header_count++;
725 /* We're beginning an explicit instantiation. */
728 begin_explicit_instantiation (void)
730 gcc_assert (!processing_explicit_instantiation);
731 processing_explicit_instantiation = true;
736 end_explicit_instantiation (void)
738 gcc_assert (processing_explicit_instantiation);
739 processing_explicit_instantiation = false;
742 /* An explicit specialization or partial specialization of TMPL is being
743 declared. Check that the namespace in which the specialization is
744 occurring is permissible. Returns false iff it is invalid to
745 specialize TMPL in the current namespace. */
748 check_specialization_namespace (tree tmpl)
750 tree tpl_ns = decl_namespace_context (tmpl);
754 An explicit specialization shall be declared in the namespace of
755 which the template is a member, or, for member templates, in the
756 namespace of which the enclosing class or enclosing class
757 template is a member. An explicit specialization of a member
758 function, member class or static data member of a class template
759 shall be declared in the namespace of which the class template is
761 if (current_scope() != DECL_CONTEXT (tmpl)
762 && !at_namespace_scope_p ())
764 error ("specialization of %qD must appear at namespace scope", tmpl);
767 if (is_associated_namespace (current_namespace, tpl_ns))
768 /* Same or super-using namespace. */
772 permerror (input_location, "specialization of %qD in different namespace", tmpl);
773 permerror (input_location, " from definition of %q+#D", tmpl);
778 /* SPEC is an explicit instantiation. Check that it is valid to
779 perform this explicit instantiation in the current namespace. */
782 check_explicit_instantiation_namespace (tree spec)
786 /* DR 275: An explicit instantiation shall appear in an enclosing
787 namespace of its template. */
788 ns = decl_namespace_context (spec);
789 if (!is_ancestor (current_namespace, ns))
790 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
791 "(which does not enclose namespace %qD)",
792 spec, current_namespace, ns);
795 /* The TYPE is being declared. If it is a template type, that means it
796 is a partial specialization. Do appropriate error-checking. */
799 maybe_process_partial_specialization (tree type)
803 if (type == error_mark_node)
804 return error_mark_node;
806 /* A lambda that appears in specialization context is not itself a
808 if (CLASS_TYPE_P (type) && CLASSTYPE_LAMBDA_EXPR (type))
811 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
813 error ("name of class shadows template template parameter %qD",
815 return error_mark_node;
818 context = TYPE_CONTEXT (type);
820 if (TYPE_ALIAS_P (type))
822 if (TYPE_TEMPLATE_INFO (type)
823 && DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (type)))
824 error ("specialization of alias template %qD",
825 TYPE_TI_TEMPLATE (type));
827 error ("explicit specialization of non-template %qT", type);
828 return error_mark_node;
830 else if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
832 /* This is for ordinary explicit specialization and partial
833 specialization of a template class such as:
835 template <> class C<int>;
839 template <class T> class C<T*>;
841 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
843 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
844 && !COMPLETE_TYPE_P (type))
846 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
847 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
848 DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (type)) = input_location;
849 if (processing_template_decl)
851 if (push_template_decl (TYPE_MAIN_DECL (type))
853 return error_mark_node;
856 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
857 error ("specialization of %qT after instantiation", type);
858 else if (errorcount && !processing_specialization
859 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type)
860 && !uses_template_parms (CLASSTYPE_TI_ARGS (type)))
861 /* Trying to define a specialization either without a template<> header
862 or in an inappropriate place. We've already given an error, so just
863 bail now so we don't actually define the specialization. */
864 return error_mark_node;
866 else if (CLASS_TYPE_P (type)
867 && !CLASSTYPE_USE_TEMPLATE (type)
868 && CLASSTYPE_TEMPLATE_INFO (type)
869 && context && CLASS_TYPE_P (context)
870 && CLASSTYPE_TEMPLATE_INFO (context))
872 /* This is for an explicit specialization of member class
873 template according to [temp.expl.spec/18]:
875 template <> template <class U> class C<int>::D;
877 The context `C<int>' must be an implicit instantiation.
878 Otherwise this is just a member class template declared
881 template <> class C<int> { template <class U> class D; };
882 template <> template <class U> class C<int>::D;
884 In the first case, `C<int>::D' is a specialization of `C<T>::D'
885 while in the second case, `C<int>::D' is a primary template
886 and `C<T>::D' may not exist. */
888 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
889 && !COMPLETE_TYPE_P (type))
892 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
894 if (current_namespace
895 != decl_namespace_context (tmpl))
897 permerror (input_location, "specializing %q#T in different namespace", type);
898 permerror (input_location, " from definition of %q+#D", tmpl);
901 /* Check for invalid specialization after instantiation:
903 template <> template <> class C<int>::D<int>;
904 template <> template <class U> class C<int>::D; */
906 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
907 t; t = TREE_CHAIN (t))
909 tree inst = TREE_VALUE (t);
910 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
912 /* We already have a full specialization of this partial
913 instantiation. Reassign it to the new member
914 specialization template. */
919 elt.tmpl = most_general_template (tmpl);
920 elt.args = CLASSTYPE_TI_ARGS (inst);
923 htab_remove_elt (type_specializations, &elt);
926 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
928 slot = htab_find_slot (type_specializations, &elt, INSERT);
929 entry = ggc_alloc_spec_entry ();
933 else if (COMPLETE_OR_OPEN_TYPE_P (inst))
934 /* But if we've had an implicit instantiation, that's a
935 problem ([temp.expl.spec]/6). */
936 error ("specialization %qT after instantiation %qT",
940 /* Mark TYPE as a specialization. And as a result, we only
941 have one level of template argument for the innermost
943 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
944 DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (type)) = input_location;
945 CLASSTYPE_TI_ARGS (type)
946 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
949 else if (processing_specialization)
951 /* Someday C++0x may allow for enum template specialization. */
952 if (cxx_dialect > cxx98 && TREE_CODE (type) == ENUMERAL_TYPE
953 && CLASS_TYPE_P (context) && CLASSTYPE_USE_TEMPLATE (context))
954 pedwarn (input_location, OPT_Wpedantic, "template specialization "
955 "of %qD not allowed by ISO C++", type);
958 error ("explicit specialization of non-template %qT", type);
959 return error_mark_node;
966 /* Returns nonzero if we can optimize the retrieval of specializations
967 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
968 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
971 optimize_specialization_lookup_p (tree tmpl)
973 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
974 && DECL_CLASS_SCOPE_P (tmpl)
975 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
977 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
978 /* The optimized lookup depends on the fact that the
979 template arguments for the member function template apply
980 purely to the containing class, which is not true if the
981 containing class is an explicit or partial
983 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
984 && !DECL_MEMBER_TEMPLATE_P (tmpl)
985 && !DECL_CONV_FN_P (tmpl)
986 /* It is possible to have a template that is not a member
987 template and is not a member of a template class:
989 template <typename T>
990 struct S { friend A::f(); };
992 Here, the friend function is a template, but the context does
993 not have template information. The optimized lookup relies
994 on having ARGS be the template arguments for both the class
995 and the function template. */
996 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
999 /* Retrieve the specialization (in the sense of [temp.spec] - a
1000 specialization is either an instantiation or an explicit
1001 specialization) of TMPL for the given template ARGS. If there is
1002 no such specialization, return NULL_TREE. The ARGS are a vector of
1003 arguments, or a vector of vectors of arguments, in the case of
1004 templates with more than one level of parameters.
1006 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
1007 then we search for a partial specialization matching ARGS. This
1008 parameter is ignored if TMPL is not a class template. */
1011 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
1013 if (args == error_mark_node)
1016 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1018 /* There should be as many levels of arguments as there are
1019 levels of parameters. */
1020 gcc_assert (TMPL_ARGS_DEPTH (args)
1021 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
1023 if (optimize_specialization_lookup_p (tmpl))
1025 tree class_template;
1026 tree class_specialization;
1027 vec<tree, va_gc> *methods;
1031 /* The template arguments actually apply to the containing
1032 class. Find the class specialization with those
1034 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
1035 class_specialization
1036 = retrieve_specialization (class_template, args, 0);
1037 if (!class_specialization)
1039 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
1040 for the specialization. */
1041 idx = class_method_index_for_fn (class_specialization, tmpl);
1044 /* Iterate through the methods with the indicated name, looking
1045 for the one that has an instance of TMPL. */
1046 methods = CLASSTYPE_METHOD_VEC (class_specialization);
1047 for (fns = (*methods)[idx]; fns; fns = OVL_NEXT (fns))
1049 tree fn = OVL_CURRENT (fns);
1050 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
1051 /* using-declarations can add base methods to the method vec,
1052 and we don't want those here. */
1053 && DECL_CONTEXT (fn) == class_specialization)
1062 htab_t specializations;
1066 elt.spec = NULL_TREE;
1068 if (DECL_CLASS_TEMPLATE_P (tmpl))
1069 specializations = type_specializations;
1071 specializations = decl_specializations;
1074 hash = hash_specialization (&elt);
1075 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1083 /* Like retrieve_specialization, but for local declarations. */
1086 retrieve_local_specialization (tree tmpl)
1090 if (local_specializations == NULL)
1093 slot = pointer_map_contains (local_specializations, tmpl);
1094 return slot ? (tree) *slot : NULL_TREE;
1097 /* Returns nonzero iff DECL is a specialization of TMPL. */
1100 is_specialization_of (tree decl, tree tmpl)
1104 if (TREE_CODE (decl) == FUNCTION_DECL)
1108 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1114 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1116 for (t = TREE_TYPE (decl);
1118 t = CLASSTYPE_USE_TEMPLATE (t)
1119 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1120 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1127 /* Returns nonzero iff DECL is a specialization of friend declaration
1128 FRIEND_DECL according to [temp.friend]. */
1131 is_specialization_of_friend (tree decl, tree friend_decl)
1133 bool need_template = true;
1136 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1137 || TREE_CODE (decl) == TYPE_DECL);
1139 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1140 of a template class, we want to check if DECL is a specialization
1142 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1143 && DECL_TEMPLATE_INFO (friend_decl)
1144 && !DECL_USE_TEMPLATE (friend_decl))
1146 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1147 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1148 need_template = false;
1150 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1151 && !PRIMARY_TEMPLATE_P (friend_decl))
1152 need_template = false;
1154 /* There is nothing to do if this is not a template friend. */
1155 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1158 if (is_specialization_of (decl, friend_decl))
1162 A member of a class template may be declared to be a friend of a
1163 non-template class. In this case, the corresponding member of
1164 every specialization of the class template is a friend of the
1165 class granting friendship.
1167 For example, given a template friend declaration
1169 template <class T> friend void A<T>::f();
1171 the member function below is considered a friend
1173 template <> struct A<int> {
1177 For this type of template friend, TEMPLATE_DEPTH below will be
1178 nonzero. To determine if DECL is a friend of FRIEND, we first
1179 check if the enclosing class is a specialization of another. */
1181 template_depth = template_class_depth (CP_DECL_CONTEXT (friend_decl));
1183 && DECL_CLASS_SCOPE_P (decl)
1184 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1185 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1187 /* Next, we check the members themselves. In order to handle
1188 a few tricky cases, such as when FRIEND_DECL's are
1190 template <class T> friend void A<T>::g(T t);
1191 template <class T> template <T t> friend void A<T>::h();
1195 void A<int>::g(int);
1196 template <int> void A<int>::h();
1198 we need to figure out ARGS, the template arguments from
1199 the context of DECL. This is required for template substitution
1200 of `T' in the function parameter of `g' and template parameter
1201 of `h' in the above examples. Here ARGS corresponds to `int'. */
1203 tree context = DECL_CONTEXT (decl);
1204 tree args = NULL_TREE;
1205 int current_depth = 0;
1207 while (current_depth < template_depth)
1209 if (CLASSTYPE_TEMPLATE_INFO (context))
1211 if (current_depth == 0)
1212 args = TYPE_TI_ARGS (context);
1214 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1217 context = TYPE_CONTEXT (context);
1220 if (TREE_CODE (decl) == FUNCTION_DECL)
1225 tree friend_args_type;
1226 tree decl_args_type;
1228 /* Make sure that both DECL and FRIEND_DECL are templates or
1230 is_template = DECL_TEMPLATE_INFO (decl)
1231 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1232 if (need_template ^ is_template)
1234 else if (is_template)
1236 /* If both are templates, check template parameter list. */
1238 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1240 if (!comp_template_parms
1241 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1245 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1248 decl_type = TREE_TYPE (decl);
1250 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1251 tf_none, NULL_TREE);
1252 if (friend_type == error_mark_node)
1255 /* Check if return types match. */
1256 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1259 /* Check if function parameter types match, ignoring the
1260 `this' parameter. */
1261 friend_args_type = TYPE_ARG_TYPES (friend_type);
1262 decl_args_type = TYPE_ARG_TYPES (decl_type);
1263 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1264 friend_args_type = TREE_CHAIN (friend_args_type);
1265 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1266 decl_args_type = TREE_CHAIN (decl_args_type);
1268 return compparms (decl_args_type, friend_args_type);
1272 /* DECL is a TYPE_DECL */
1274 tree decl_type = TREE_TYPE (decl);
1276 /* Make sure that both DECL and FRIEND_DECL are templates or
1279 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1280 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1282 if (need_template ^ is_template)
1284 else if (is_template)
1287 /* If both are templates, check the name of the two
1288 TEMPLATE_DECL's first because is_friend didn't. */
1289 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1290 != DECL_NAME (friend_decl))
1293 /* Now check template parameter list. */
1295 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1297 return comp_template_parms
1298 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1302 return (DECL_NAME (decl)
1303 == DECL_NAME (friend_decl));
1309 /* Register the specialization SPEC as a specialization of TMPL with
1310 the indicated ARGS. IS_FRIEND indicates whether the specialization
1311 is actually just a friend declaration. Returns SPEC, or an
1312 equivalent prior declaration, if available. */
1315 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1322 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1324 if (TREE_CODE (spec) == FUNCTION_DECL
1325 && uses_template_parms (DECL_TI_ARGS (spec)))
1326 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1327 register it; we want the corresponding TEMPLATE_DECL instead.
1328 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1329 the more obvious `uses_template_parms (spec)' to avoid problems
1330 with default function arguments. In particular, given
1331 something like this:
1333 template <class T> void f(T t1, T t = T())
1335 the default argument expression is not substituted for in an
1336 instantiation unless and until it is actually needed. */
1339 if (optimize_specialization_lookup_p (tmpl))
1340 /* We don't put these specializations in the hash table, but we might
1341 want to give an error about a mismatch. */
1342 fn = retrieve_specialization (tmpl, args, 0);
1350 hash = hash_specialization (&elt);
1353 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1355 fn = ((spec_entry *) *slot)->spec;
1360 /* We can sometimes try to re-register a specialization that we've
1361 already got. In particular, regenerate_decl_from_template calls
1362 duplicate_decls which will update the specialization list. But,
1363 we'll still get called again here anyhow. It's more convenient
1364 to simply allow this than to try to prevent it. */
1367 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1369 if (DECL_TEMPLATE_INSTANTIATION (fn))
1371 if (DECL_ODR_USED (fn)
1372 || DECL_EXPLICIT_INSTANTIATION (fn))
1374 error ("specialization of %qD after instantiation",
1376 return error_mark_node;
1381 /* This situation should occur only if the first
1382 specialization is an implicit instantiation, the
1383 second is an explicit specialization, and the
1384 implicit instantiation has not yet been used. That
1385 situation can occur if we have implicitly
1386 instantiated a member function and then specialized
1389 We can also wind up here if a friend declaration that
1390 looked like an instantiation turns out to be a
1393 template <class T> void foo(T);
1394 class S { friend void foo<>(int) };
1395 template <> void foo(int);
1397 We transform the existing DECL in place so that any
1398 pointers to it become pointers to the updated
1401 If there was a definition for the template, but not
1402 for the specialization, we want this to look as if
1403 there were no definition, and vice versa. */
1404 DECL_INITIAL (fn) = NULL_TREE;
1405 duplicate_decls (spec, fn, is_friend);
1406 /* The call to duplicate_decls will have applied
1409 An explicit specialization of a function template
1410 is inline only if it is explicitly declared to be,
1411 and independently of whether its function template
1414 to the primary function; now copy the inline bits to
1415 the various clones. */
1416 FOR_EACH_CLONE (clone, fn)
1418 DECL_DECLARED_INLINE_P (clone)
1419 = DECL_DECLARED_INLINE_P (fn);
1420 DECL_SOURCE_LOCATION (clone)
1421 = DECL_SOURCE_LOCATION (fn);
1423 check_specialization_namespace (tmpl);
1428 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1430 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1431 /* Dup decl failed, but this is a new definition. Set the
1432 line number so any errors match this new
1434 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1440 return duplicate_decls (spec, fn, is_friend);
1442 /* A specialization must be declared in the same namespace as the
1443 template it is specializing. */
1444 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1445 && !check_specialization_namespace (tmpl))
1446 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1448 if (slot != NULL /* !optimize_specialization_lookup_p (tmpl) */)
1450 spec_entry *entry = ggc_alloc_spec_entry ();
1451 gcc_assert (tmpl && args && spec);
1454 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1455 && PRIMARY_TEMPLATE_P (tmpl)
1456 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1457 /* TMPL is a forward declaration of a template function; keep a list
1458 of all specializations in case we need to reassign them to a friend
1459 template later in tsubst_friend_function. */
1460 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1461 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1467 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1468 TMPL and ARGS members, ignores SPEC. */
1470 int comparing_specializations;
1473 eq_specializations (const void *p1, const void *p2)
1475 const spec_entry *e1 = (const spec_entry *)p1;
1476 const spec_entry *e2 = (const spec_entry *)p2;
1479 ++comparing_specializations;
1480 equal = (e1->tmpl == e2->tmpl
1481 && comp_template_args (e1->args, e2->args));
1482 --comparing_specializations;
1487 /* Returns a hash for a template TMPL and template arguments ARGS. */
1490 hash_tmpl_and_args (tree tmpl, tree args)
1492 hashval_t val = DECL_UID (tmpl);
1493 return iterative_hash_template_arg (args, val);
1496 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1500 hash_specialization (const void *p)
1502 const spec_entry *e = (const spec_entry *)p;
1503 return hash_tmpl_and_args (e->tmpl, e->args);
1506 /* Recursively calculate a hash value for a template argument ARG, for use
1507 in the hash tables of template specializations. */
1510 iterative_hash_template_arg (tree arg, hashval_t val)
1512 unsigned HOST_WIDE_INT i;
1513 enum tree_code code;
1516 if (arg == NULL_TREE)
1517 return iterative_hash_object (arg, val);
1522 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
1523 /* We can get one of these when re-hashing a previous entry in the middle
1524 of substituting into a pack expansion. Just look through it. */
1525 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1527 code = TREE_CODE (arg);
1528 tclass = TREE_CODE_CLASS (code);
1530 val = iterative_hash_object (code, val);
1537 case IDENTIFIER_NODE:
1538 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1542 int i, len = TREE_VEC_LENGTH (arg);
1543 for (i = 0; i < len; ++i)
1544 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1548 case TYPE_PACK_EXPANSION:
1549 case EXPR_PACK_EXPANSION:
1550 val = iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1551 return iterative_hash_template_arg (PACK_EXPANSION_EXTRA_ARGS (arg), val);
1553 case TYPE_ARGUMENT_PACK:
1554 case NONTYPE_ARGUMENT_PACK:
1555 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1558 for (; arg; arg = TREE_CHAIN (arg))
1559 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1563 for (; arg; arg = OVL_NEXT (arg))
1564 val = iterative_hash_template_arg (OVL_CURRENT (arg), val);
1570 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1572 val = iterative_hash_template_arg (field, val);
1573 val = iterative_hash_template_arg (value, val);
1579 if (!DECL_ARTIFICIAL (arg))
1581 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1582 val = iterative_hash_object (DECL_PARM_LEVEL (arg), val);
1584 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1587 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1590 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1591 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1593 case TEMPLATE_PARM_INDEX:
1594 val = iterative_hash_template_arg
1595 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1596 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1597 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1600 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1601 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1602 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1605 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1607 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1611 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1612 code = TREE_CODE (TREE_OPERAND (arg, 1));
1613 val = iterative_hash_object (code, val);
1614 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1617 /* A lambda can't appear in a template arg, but don't crash on
1619 gcc_assert (seen_error ());
1623 case IMPLICIT_CONV_EXPR:
1624 case STATIC_CAST_EXPR:
1625 case REINTERPRET_CAST_EXPR:
1626 case CONST_CAST_EXPR:
1627 case DYNAMIC_CAST_EXPR:
1629 val = iterative_hash_template_arg (TREE_TYPE (arg), val);
1630 /* Now hash operands as usual. */
1640 if (TYPE_CANONICAL (arg))
1641 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1643 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1644 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1645 /* Otherwise just compare the types during lookup. */
1648 case tcc_declaration:
1650 return iterative_hash_expr (arg, val);
1653 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1655 unsigned n = cp_tree_operand_length (arg);
1656 for (i = 0; i < n; ++i)
1657 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1665 /* Unregister the specialization SPEC as a specialization of TMPL.
1666 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1667 if the SPEC was listed as a specialization of TMPL.
1669 Note that SPEC has been ggc_freed, so we can't look inside it. */
1672 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1677 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1678 elt.args = TI_ARGS (tinfo);
1679 elt.spec = NULL_TREE;
1681 entry = (spec_entry *) htab_find (decl_specializations, &elt);
1684 gcc_assert (entry->spec == spec || entry->spec == new_spec);
1685 gcc_assert (new_spec != NULL_TREE);
1686 entry->spec = new_spec;
1693 /* Like register_specialization, but for local declarations. We are
1694 registering SPEC, an instantiation of TMPL. */
1697 register_local_specialization (tree spec, tree tmpl)
1701 slot = pointer_map_insert (local_specializations, tmpl);
1705 /* TYPE is a class type. Returns true if TYPE is an explicitly
1706 specialized class. */
1709 explicit_class_specialization_p (tree type)
1711 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1713 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1716 /* Print the list of functions at FNS, going through all the overloads
1717 for each element of the list. Alternatively, FNS can not be a
1718 TREE_LIST, in which case it will be printed together with all the
1721 MORE and *STR should respectively be FALSE and NULL when the function
1722 is called from the outside. They are used internally on recursive
1723 calls. print_candidates manages the two parameters and leaves NULL
1724 in *STR when it ends. */
1727 print_candidates_1 (tree fns, bool more, const char **str)
1730 char *spaces = NULL;
1732 for (fn = fns; fn; fn = OVL_NEXT (fn))
1733 if (TREE_CODE (fn) == TREE_LIST)
1735 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2))
1736 print_candidates_1 (TREE_VALUE (fn2),
1737 TREE_CHAIN (fn2) || more, str);
1741 tree cand = OVL_CURRENT (fn);
1744 /* Pick the prefix string. */
1745 if (!more && !OVL_NEXT (fns))
1747 inform (DECL_SOURCE_LOCATION (cand),
1748 "candidate is: %#D", cand);
1752 *str = _("candidates are:");
1753 spaces = get_spaces (*str);
1755 inform (DECL_SOURCE_LOCATION (cand), "%s %#D", *str, cand);
1756 *str = spaces ? spaces : *str;
1766 /* Print the list of candidate FNS in an error message. FNS can also
1767 be a TREE_LIST of non-functions in the case of an ambiguous lookup. */
1770 print_candidates (tree fns)
1772 const char *str = NULL;
1773 print_candidates_1 (fns, false, &str);
1774 gcc_assert (str == NULL);
1777 /* Returns the template (one of the functions given by TEMPLATE_ID)
1778 which can be specialized to match the indicated DECL with the
1779 explicit template args given in TEMPLATE_ID. The DECL may be
1780 NULL_TREE if none is available. In that case, the functions in
1781 TEMPLATE_ID are non-members.
1783 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1784 specialization of a member template.
1786 The TEMPLATE_COUNT is the number of references to qualifying
1787 template classes that appeared in the name of the function. See
1788 check_explicit_specialization for a more accurate description.
1790 TSK indicates what kind of template declaration (if any) is being
1791 declared. TSK_TEMPLATE indicates that the declaration given by
1792 DECL, though a FUNCTION_DECL, has template parameters, and is
1793 therefore a template function.
1795 The template args (those explicitly specified and those deduced)
1796 are output in a newly created vector *TARGS_OUT.
1798 If it is impossible to determine the result, an error message is
1799 issued. The error_mark_node is returned to indicate failure. */
1802 determine_specialization (tree template_id,
1805 int need_member_template,
1811 tree explicit_targs;
1812 tree candidates = NULL_TREE;
1813 /* A TREE_LIST of templates of which DECL may be a specialization.
1814 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1815 corresponding TREE_PURPOSE is the set of template arguments that,
1816 when used to instantiate the template, would produce a function
1817 with the signature of DECL. */
1818 tree templates = NULL_TREE;
1820 cp_binding_level *b;
1822 *targs_out = NULL_TREE;
1824 if (template_id == error_mark_node || decl == error_mark_node)
1825 return error_mark_node;
1827 /* We shouldn't be specializing a member template of an
1828 unspecialized class template; we already gave an error in
1829 check_specialization_scope, now avoid crashing. */
1830 if (template_count && DECL_CLASS_SCOPE_P (decl)
1831 && template_class_depth (DECL_CONTEXT (decl)) > 0)
1833 gcc_assert (errorcount);
1834 return error_mark_node;
1837 fns = TREE_OPERAND (template_id, 0);
1838 explicit_targs = TREE_OPERAND (template_id, 1);
1840 if (fns == error_mark_node)
1841 return error_mark_node;
1843 /* Check for baselinks. */
1844 if (BASELINK_P (fns))
1845 fns = BASELINK_FUNCTIONS (fns);
1847 if (!is_overloaded_fn (fns))
1849 error ("%qD is not a function template", fns);
1850 return error_mark_node;
1853 /* Count the number of template headers specified for this
1856 for (b = current_binding_level;
1857 b->kind == sk_template_parms;
1861 for (; fns; fns = OVL_NEXT (fns))
1863 tree fn = OVL_CURRENT (fns);
1865 if (TREE_CODE (fn) == TEMPLATE_DECL)
1867 tree decl_arg_types;
1871 /* In case of explicit specialization, we need to check if
1872 the number of template headers appearing in the specialization
1873 is correct. This is usually done in check_explicit_specialization,
1874 but the check done there cannot be exhaustive when specializing
1875 member functions. Consider the following code:
1877 template <> void A<int>::f(int);
1878 template <> template <> void A<int>::f(int);
1880 Assuming that A<int> is not itself an explicit specialization
1881 already, the first line specializes "f" which is a non-template
1882 member function, whilst the second line specializes "f" which
1883 is a template member function. So both lines are syntactically
1884 correct, and check_explicit_specialization does not reject
1887 Here, we can do better, as we are matching the specialization
1888 against the declarations. We count the number of template
1889 headers, and we check if they match TEMPLATE_COUNT + 1
1890 (TEMPLATE_COUNT is the number of qualifying template classes,
1891 plus there must be another header for the member template
1894 Notice that if header_count is zero, this is not a
1895 specialization but rather a template instantiation, so there
1896 is no check we can perform here. */
1897 if (header_count && header_count != template_count + 1)
1900 /* Check that the number of template arguments at the
1901 innermost level for DECL is the same as for FN. */
1902 if (current_binding_level->kind == sk_template_parms
1903 && !current_binding_level->explicit_spec_p
1904 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1905 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1906 (current_template_parms))))
1909 /* DECL might be a specialization of FN. */
1910 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1911 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1913 /* For a non-static member function, we need to make sure
1914 that the const qualification is the same. Since
1915 get_bindings does not try to merge the "this" parameter,
1916 we must do the comparison explicitly. */
1917 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1918 && !same_type_p (TREE_VALUE (fn_arg_types),
1919 TREE_VALUE (decl_arg_types)))
1922 /* Skip the "this" parameter and, for constructors of
1923 classes with virtual bases, the VTT parameter. A
1924 full specialization of a constructor will have a VTT
1925 parameter, but a template never will. */
1927 = skip_artificial_parms_for (decl, decl_arg_types);
1929 = skip_artificial_parms_for (fn, fn_arg_types);
1931 /* Function templates cannot be specializations; there are
1932 no partial specializations of functions. Therefore, if
1933 the type of DECL does not match FN, there is no
1935 if (tsk == tsk_template)
1937 if (compparms (fn_arg_types, decl_arg_types))
1938 candidates = tree_cons (NULL_TREE, fn, candidates);
1942 /* See whether this function might be a specialization of this
1943 template. Suppress access control because we might be trying
1944 to make this specialization a friend, and we have already done
1945 access control for the declaration of the specialization. */
1946 push_deferring_access_checks (dk_no_check);
1947 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1948 pop_deferring_access_checks ();
1951 /* We cannot deduce template arguments that when used to
1952 specialize TMPL will produce DECL. */
1955 /* Make sure that the deduced arguments actually work. */
1956 insttype = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE);
1957 if (insttype == error_mark_node)
1960 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (insttype));
1961 if (!compparms (fn_arg_types, decl_arg_types))
1964 /* Save this template, and the arguments deduced. */
1965 templates = tree_cons (targs, fn, templates);
1967 else if (need_member_template)
1968 /* FN is an ordinary member function, and we need a
1969 specialization of a member template. */
1971 else if (TREE_CODE (fn) != FUNCTION_DECL)
1972 /* We can get IDENTIFIER_NODEs here in certain erroneous
1975 else if (!DECL_FUNCTION_MEMBER_P (fn))
1976 /* This is just an ordinary non-member function. Nothing can
1977 be a specialization of that. */
1979 else if (DECL_ARTIFICIAL (fn))
1980 /* Cannot specialize functions that are created implicitly. */
1984 tree decl_arg_types;
1986 /* This is an ordinary member function. However, since
1987 we're here, we can assume it's enclosing class is a
1988 template class. For example,
1990 template <typename T> struct S { void f(); };
1991 template <> void S<int>::f() {}
1993 Here, S<int>::f is a non-template, but S<int> is a
1994 template class. If FN has the same type as DECL, we
1995 might be in business. */
1997 if (!DECL_TEMPLATE_INFO (fn))
1998 /* Its enclosing class is an explicit specialization
1999 of a template class. This is not a candidate. */
2002 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
2003 TREE_TYPE (TREE_TYPE (fn))))
2004 /* The return types differ. */
2007 /* Adjust the type of DECL in case FN is a static member. */
2008 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
2009 if (DECL_STATIC_FUNCTION_P (fn)
2010 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2011 decl_arg_types = TREE_CHAIN (decl_arg_types);
2013 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
2016 candidates = tree_cons (NULL_TREE, fn, candidates);
2020 if (templates && TREE_CHAIN (templates))
2026 It is possible for a specialization with a given function
2027 signature to be instantiated from more than one function
2028 template. In such cases, explicit specification of the
2029 template arguments must be used to uniquely identify the
2030 function template specialization being specialized.
2032 Note that here, there's no suggestion that we're supposed to
2033 determine which of the candidate templates is most
2034 specialized. However, we, also have:
2038 Partial ordering of overloaded function template
2039 declarations is used in the following contexts to select
2040 the function template to which a function template
2041 specialization refers:
2043 -- when an explicit specialization refers to a function
2046 So, we do use the partial ordering rules, at least for now.
2047 This extension can only serve to make invalid programs valid,
2048 so it's safe. And, there is strong anecdotal evidence that
2049 the committee intended the partial ordering rules to apply;
2050 the EDG front end has that behavior, and John Spicer claims
2051 that the committee simply forgot to delete the wording in
2052 [temp.expl.spec]. */
2053 tree tmpl = most_specialized_instantiation (templates);
2054 if (tmpl != error_mark_node)
2057 TREE_CHAIN (templates) = NULL_TREE;
2061 if (templates == NULL_TREE && candidates == NULL_TREE)
2063 error ("template-id %qD for %q+D does not match any template "
2064 "declaration", template_id, decl);
2065 if (header_count && header_count != template_count + 1)
2066 inform (input_location, "saw %d %<template<>%>, need %d for "
2067 "specializing a member function template",
2068 header_count, template_count + 1);
2069 return error_mark_node;
2071 else if ((templates && TREE_CHAIN (templates))
2072 || (candidates && TREE_CHAIN (candidates))
2073 || (templates && candidates))
2075 error ("ambiguous template specialization %qD for %q+D",
2077 candidates = chainon (candidates, templates);
2078 print_candidates (candidates);
2079 return error_mark_node;
2082 /* We have one, and exactly one, match. */
2085 tree fn = TREE_VALUE (candidates);
2086 *targs_out = copy_node (DECL_TI_ARGS (fn));
2087 /* DECL is a re-declaration or partial instantiation of a template
2089 if (TREE_CODE (fn) == TEMPLATE_DECL)
2091 /* It was a specialization of an ordinary member function in a
2093 return DECL_TI_TEMPLATE (fn);
2096 /* It was a specialization of a template. */
2097 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
2098 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
2100 *targs_out = copy_node (targs);
2101 SET_TMPL_ARGS_LEVEL (*targs_out,
2102 TMPL_ARGS_DEPTH (*targs_out),
2103 TREE_PURPOSE (templates));
2106 *targs_out = TREE_PURPOSE (templates);
2107 return TREE_VALUE (templates);
2110 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
2111 but with the default argument values filled in from those in the
2115 copy_default_args_to_explicit_spec_1 (tree spec_types,
2118 tree new_spec_types;
2123 if (spec_types == void_list_node)
2124 return void_list_node;
2126 /* Substitute into the rest of the list. */
2128 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
2129 TREE_CHAIN (tmpl_types));
2131 /* Add the default argument for this parameter. */
2132 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
2133 TREE_VALUE (spec_types),
2137 /* DECL is an explicit specialization. Replicate default arguments
2138 from the template it specializes. (That way, code like:
2140 template <class T> void f(T = 3);
2141 template <> void f(double);
2144 works, as required.) An alternative approach would be to look up
2145 the correct default arguments at the call-site, but this approach
2146 is consistent with how implicit instantiations are handled. */
2149 copy_default_args_to_explicit_spec (tree decl)
2154 tree new_spec_types;
2158 tree object_type = NULL_TREE;
2159 tree in_charge = NULL_TREE;
2160 tree vtt = NULL_TREE;
2162 /* See if there's anything we need to do. */
2163 tmpl = DECL_TI_TEMPLATE (decl);
2164 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2165 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2166 if (TREE_PURPOSE (t))
2171 old_type = TREE_TYPE (decl);
2172 spec_types = TYPE_ARG_TYPES (old_type);
2174 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2176 /* Remove the this pointer, but remember the object's type for
2178 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2179 spec_types = TREE_CHAIN (spec_types);
2180 tmpl_types = TREE_CHAIN (tmpl_types);
2182 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2184 /* DECL may contain more parameters than TMPL due to the extra
2185 in-charge parameter in constructors and destructors. */
2186 in_charge = spec_types;
2187 spec_types = TREE_CHAIN (spec_types);
2189 if (DECL_HAS_VTT_PARM_P (decl))
2192 spec_types = TREE_CHAIN (spec_types);
2196 /* Compute the merged default arguments. */
2198 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2200 /* Compute the new FUNCTION_TYPE. */
2204 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2209 /* Put the in-charge parameter back. */
2210 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2211 TREE_VALUE (in_charge),
2214 new_type = build_method_type_directly (object_type,
2215 TREE_TYPE (old_type),
2219 new_type = build_function_type (TREE_TYPE (old_type),
2221 new_type = cp_build_type_attribute_variant (new_type,
2222 TYPE_ATTRIBUTES (old_type));
2223 new_type = build_exception_variant (new_type,
2224 TYPE_RAISES_EXCEPTIONS (old_type));
2225 TREE_TYPE (decl) = new_type;
2228 /* Return the number of template headers we expect to see for a definition
2229 or specialization of CTYPE or one of its non-template members. */
2232 num_template_headers_for_class (tree ctype)
2234 int num_templates = 0;
2236 while (ctype && CLASS_TYPE_P (ctype))
2238 /* You're supposed to have one `template <...>' for every
2239 template class, but you don't need one for a full
2240 specialization. For example:
2242 template <class T> struct S{};
2243 template <> struct S<int> { void f(); };
2244 void S<int>::f () {}
2246 is correct; there shouldn't be a `template <>' for the
2247 definition of `S<int>::f'. */
2248 if (!CLASSTYPE_TEMPLATE_INFO (ctype))
2249 /* If CTYPE does not have template information of any
2250 kind, then it is not a template, nor is it nested
2251 within a template. */
2253 if (explicit_class_specialization_p (ctype))
2255 if (PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (ctype)))
2258 ctype = TYPE_CONTEXT (ctype);
2261 return num_templates;
2264 /* Do a simple sanity check on the template headers that precede the
2265 variable declaration DECL. */
2268 check_template_variable (tree decl)
2270 tree ctx = CP_DECL_CONTEXT (decl);
2271 int wanted = num_template_headers_for_class (ctx);
2272 if (!TYPE_P (ctx) || !CLASSTYPE_TEMPLATE_INFO (ctx))
2273 permerror (DECL_SOURCE_LOCATION (decl),
2274 "%qD is not a static data member of a class template", decl);
2275 else if (template_header_count > wanted)
2277 pedwarn (DECL_SOURCE_LOCATION (decl), 0,
2278 "too many template headers for %D (should be %d)",
2280 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (ctx))
2281 inform (DECL_SOURCE_LOCATION (decl),
2282 "members of an explicitly specialized class are defined "
2283 "without a template header");
2287 /* Check to see if the function just declared, as indicated in
2288 DECLARATOR, and in DECL, is a specialization of a function
2289 template. We may also discover that the declaration is an explicit
2290 instantiation at this point.
2292 Returns DECL, or an equivalent declaration that should be used
2293 instead if all goes well. Issues an error message if something is
2294 amiss. Returns error_mark_node if the error is not easily
2297 FLAGS is a bitmask consisting of the following flags:
2299 2: The function has a definition.
2300 4: The function is a friend.
2302 The TEMPLATE_COUNT is the number of references to qualifying
2303 template classes that appeared in the name of the function. For
2306 template <class T> struct S { void f(); };
2309 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2310 classes are not counted in the TEMPLATE_COUNT, so that in
2312 template <class T> struct S {};
2313 template <> struct S<int> { void f(); }
2314 template <> void S<int>::f();
2316 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2317 invalid; there should be no template <>.)
2319 If the function is a specialization, it is marked as such via
2320 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2321 is set up correctly, and it is added to the list of specializations
2322 for that template. */
2325 check_explicit_specialization (tree declarator,
2330 int have_def = flags & 2;
2331 int is_friend = flags & 4;
2332 int specialization = 0;
2333 int explicit_instantiation = 0;
2334 int member_specialization = 0;
2335 tree ctype = DECL_CLASS_CONTEXT (decl);
2336 tree dname = DECL_NAME (decl);
2341 if (!processing_specialization)
2344 tsk = tsk_excessive_parms;
2347 tsk = current_tmpl_spec_kind (template_count);
2352 if (processing_specialization)
2355 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2357 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2360 /* This could be something like:
2362 template <class T> void f(T);
2363 class S { friend void f<>(int); } */
2367 /* This case handles bogus declarations like template <>
2368 template <class T> void f<int>(); */
2370 error ("template-id %qD in declaration of primary template",
2377 case tsk_invalid_member_spec:
2378 /* The error has already been reported in
2379 check_specialization_scope. */
2380 return error_mark_node;
2382 case tsk_invalid_expl_inst:
2383 error ("template parameter list used in explicit instantiation");
2389 error ("definition provided for explicit instantiation");
2391 explicit_instantiation = 1;
2394 case tsk_excessive_parms:
2395 case tsk_insufficient_parms:
2396 if (tsk == tsk_excessive_parms)
2397 error ("too many template parameter lists in declaration of %qD",
2399 else if (template_header_count)
2400 error("too few template parameter lists in declaration of %qD", decl);
2402 error("explicit specialization of %qD must be introduced by "
2403 "%<template <>%>", decl);
2407 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2409 member_specialization = 1;
2415 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2417 /* This case handles bogus declarations like template <>
2418 template <class T> void f<int>(); */
2420 if (uses_template_parms (declarator))
2421 error ("function template partial specialization %qD "
2422 "is not allowed", declarator);
2424 error ("template-id %qD in declaration of primary template",
2429 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2430 /* This is a specialization of a member template, without
2431 specialization the containing class. Something like:
2433 template <class T> struct S {
2434 template <class U> void f (U);
2436 template <> template <class U> void S<int>::f(U) {}
2438 That's a specialization -- but of the entire template. */
2446 if (specialization || member_specialization)
2448 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2449 for (; t; t = TREE_CHAIN (t))
2450 if (TREE_PURPOSE (t))
2452 permerror (input_location,
2453 "default argument specified in explicit specialization");
2458 if (specialization || member_specialization || explicit_instantiation)
2460 tree tmpl = NULL_TREE;
2461 tree targs = NULL_TREE;
2463 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2464 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2468 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2473 /* If there is no class context, the explicit instantiation
2474 must be at namespace scope. */
2475 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2477 /* Find the namespace binding, using the declaration
2479 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2481 if (fns == error_mark_node || !is_overloaded_fn (fns))
2483 error ("%qD is not a template function", dname);
2484 fns = error_mark_node;
2488 tree fn = OVL_CURRENT (fns);
2489 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2490 CP_DECL_CONTEXT (fn)))
2491 error ("%qD is not declared in %qD",
2492 decl, current_namespace);
2496 declarator = lookup_template_function (fns, NULL_TREE);
2499 if (declarator == error_mark_node)
2500 return error_mark_node;
2502 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2504 if (!explicit_instantiation)
2505 /* A specialization in class scope. This is invalid,
2506 but the error will already have been flagged by
2507 check_specialization_scope. */
2508 return error_mark_node;
2511 /* It's not valid to write an explicit instantiation in
2514 class C { template void f(); }
2516 This case is caught by the parser. However, on
2519 template class C { void f(); };
2521 (which is invalid) we can get here. The error will be
2528 else if (ctype != NULL_TREE
2529 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2532 /* Find the list of functions in ctype that have the same
2533 name as the declared function. */
2534 tree name = TREE_OPERAND (declarator, 0);
2535 tree fns = NULL_TREE;
2538 if (constructor_name_p (name, ctype))
2540 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2542 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2543 : !CLASSTYPE_DESTRUCTORS (ctype))
2545 /* From [temp.expl.spec]:
2547 If such an explicit specialization for the member
2548 of a class template names an implicitly-declared
2549 special member function (clause _special_), the
2550 program is ill-formed.
2552 Similar language is found in [temp.explicit]. */
2553 error ("specialization of implicitly-declared special member function");
2554 return error_mark_node;
2557 name = is_constructor ? ctor_identifier : dtor_identifier;
2560 if (!DECL_CONV_FN_P (decl))
2562 idx = lookup_fnfields_1 (ctype, name);
2564 fns = (*CLASSTYPE_METHOD_VEC (ctype))[idx];
2568 vec<tree, va_gc> *methods;
2571 /* For a type-conversion operator, we cannot do a
2572 name-based lookup. We might be looking for `operator
2573 int' which will be a specialization of `operator T'.
2574 So, we find *all* the conversion operators, and then
2575 select from them. */
2578 methods = CLASSTYPE_METHOD_VEC (ctype);
2580 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2581 methods->iterate (idx, &ovl);
2584 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2585 /* There are no more conversion functions. */
2588 /* Glue all these conversion functions together
2589 with those we already have. */
2590 for (; ovl; ovl = OVL_NEXT (ovl))
2591 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2595 if (fns == NULL_TREE)
2597 error ("no member function %qD declared in %qT", name, ctype);
2598 return error_mark_node;
2601 TREE_OPERAND (declarator, 0) = fns;
2604 /* Figure out what exactly is being specialized at this point.
2605 Note that for an explicit instantiation, even one for a
2606 member function, we cannot tell apriori whether the
2607 instantiation is for a member template, or just a member
2608 function of a template class. Even if a member template is
2609 being instantiated, the member template arguments may be
2610 elided if they can be deduced from the rest of the
2612 tmpl = determine_specialization (declarator, decl,
2614 member_specialization,
2618 if (!tmpl || tmpl == error_mark_node)
2619 /* We couldn't figure out what this declaration was
2621 return error_mark_node;
2624 tree gen_tmpl = most_general_template (tmpl);
2626 if (explicit_instantiation)
2628 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2629 is done by do_decl_instantiation later. */
2631 int arg_depth = TMPL_ARGS_DEPTH (targs);
2632 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2634 if (arg_depth > parm_depth)
2636 /* If TMPL is not the most general template (for
2637 example, if TMPL is a friend template that is
2638 injected into namespace scope), then there will
2639 be too many levels of TARGS. Remove some of them
2644 new_targs = make_tree_vec (parm_depth);
2645 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2646 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2647 = TREE_VEC_ELT (targs, i);
2651 return instantiate_template (tmpl, targs, tf_error);
2654 /* If we thought that the DECL was a member function, but it
2655 turns out to be specializing a static member function,
2656 make DECL a static member function as well. */
2657 if (DECL_STATIC_FUNCTION_P (tmpl)
2658 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2659 revert_static_member_fn (decl);
2661 /* If this is a specialization of a member template of a
2662 template class, we want to return the TEMPLATE_DECL, not
2663 the specialization of it. */
2664 if (tsk == tsk_template)
2666 tree result = DECL_TEMPLATE_RESULT (tmpl);
2667 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2668 DECL_INITIAL (result) = NULL_TREE;
2672 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2673 DECL_SOURCE_LOCATION (result)
2674 = DECL_SOURCE_LOCATION (decl);
2675 /* We want to use the argument list specified in the
2676 definition, not in the original declaration. */
2677 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2678 for (parm = DECL_ARGUMENTS (result); parm;
2679 parm = DECL_CHAIN (parm))
2680 DECL_CONTEXT (parm) = result;
2682 return register_specialization (tmpl, gen_tmpl, targs,
2686 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2687 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs);
2689 /* Inherit default function arguments from the template
2690 DECL is specializing. */
2691 copy_default_args_to_explicit_spec (decl);
2693 /* This specialization has the same protection as the
2694 template it specializes. */
2695 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2696 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2698 /* 7.1.1-1 [dcl.stc]
2700 A storage-class-specifier shall not be specified in an
2701 explicit specialization...
2703 The parser rejects these, so unless action is taken here,
2704 explicit function specializations will always appear with
2707 The action recommended by the C++ CWG in response to C++
2708 defect report 605 is to make the storage class and linkage
2709 of the explicit specialization match the templated function:
2711 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2713 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2715 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2716 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2718 /* This specialization has the same linkage and visibility as
2719 the function template it specializes. */
2720 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2721 if (! TREE_PUBLIC (decl))
2723 DECL_INTERFACE_KNOWN (decl) = 1;
2724 DECL_NOT_REALLY_EXTERN (decl) = 1;
2726 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2727 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2729 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2730 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2734 /* If DECL is a friend declaration, declared using an
2735 unqualified name, the namespace associated with DECL may
2736 have been set incorrectly. For example, in:
2738 template <typename T> void f(T);
2740 struct S { friend void f<int>(int); }
2743 we will have set the DECL_CONTEXT for the friend
2744 declaration to N, rather than to the global namespace. */
2745 if (DECL_NAMESPACE_SCOPE_P (decl))
2746 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2748 if (is_friend && !have_def)
2749 /* This is not really a declaration of a specialization.
2750 It's just the name of an instantiation. But, it's not
2751 a request for an instantiation, either. */
2752 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2753 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2754 /* This is indeed a specialization. In case of constructors
2755 and destructors, we need in-charge and not-in-charge
2756 versions in V3 ABI. */
2757 clone_function_decl (decl, /*update_method_vec_p=*/0);
2759 /* Register this specialization so that we can find it
2761 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2768 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2769 parameters. These are represented in the same format used for
2770 DECL_TEMPLATE_PARMS. */
2773 comp_template_parms (const_tree parms1, const_tree parms2)
2778 if (parms1 == parms2)
2781 for (p1 = parms1, p2 = parms2;
2782 p1 != NULL_TREE && p2 != NULL_TREE;
2783 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2785 tree t1 = TREE_VALUE (p1);
2786 tree t2 = TREE_VALUE (p2);
2789 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2790 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2792 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2795 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2797 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2798 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2800 /* If either of the template parameters are invalid, assume
2801 they match for the sake of error recovery. */
2802 if (parm1 == error_mark_node || parm2 == error_mark_node)
2805 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2808 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2809 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2810 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2812 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2817 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2818 /* One set of parameters has more parameters lists than the
2825 /* Determine whether PARM is a parameter pack. */
2828 template_parameter_pack_p (const_tree parm)
2830 /* Determine if we have a non-type template parameter pack. */
2831 if (TREE_CODE (parm) == PARM_DECL)
2832 return (DECL_TEMPLATE_PARM_P (parm)
2833 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2834 if (TREE_CODE (parm) == TEMPLATE_PARM_INDEX)
2835 return TEMPLATE_PARM_PARAMETER_PACK (parm);
2837 /* If this is a list of template parameters, we could get a
2838 TYPE_DECL or a TEMPLATE_DECL. */
2839 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2840 parm = TREE_TYPE (parm);
2842 /* Otherwise it must be a type template parameter. */
2843 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2844 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2845 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2848 /* Determine if T is a function parameter pack. */
2851 function_parameter_pack_p (const_tree t)
2853 if (t && TREE_CODE (t) == PARM_DECL)
2854 return FUNCTION_PARAMETER_PACK_P (t);
2858 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST.
2859 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */
2862 get_function_template_decl (const_tree primary_func_tmpl_inst)
2864 if (! primary_func_tmpl_inst
2865 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL
2866 || ! primary_template_instantiation_p (primary_func_tmpl_inst))
2869 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst));
2872 /* Return true iff the function parameter PARAM_DECL was expanded
2873 from the function parameter pack PACK. */
2876 function_parameter_expanded_from_pack_p (tree param_decl, tree pack)
2878 if (DECL_ARTIFICIAL (param_decl)
2879 || !function_parameter_pack_p (pack))
2882 /* The parameter pack and its pack arguments have the same
2884 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl);
2887 /* Determine whether ARGS describes a variadic template args list,
2888 i.e., one that is terminated by a template argument pack. */
2891 template_args_variadic_p (tree args)
2896 if (args == NULL_TREE)
2899 args = INNERMOST_TEMPLATE_ARGS (args);
2900 nargs = TREE_VEC_LENGTH (args);
2905 last_parm = TREE_VEC_ELT (args, nargs - 1);
2907 return ARGUMENT_PACK_P (last_parm);
2910 /* Generate a new name for the parameter pack name NAME (an
2911 IDENTIFIER_NODE) that incorporates its */
2914 make_ith_pack_parameter_name (tree name, int i)
2916 /* Munge the name to include the parameter index. */
2917 #define NUMBUF_LEN 128
2918 char numbuf[NUMBUF_LEN];
2922 if (name == NULL_TREE)
2924 snprintf (numbuf, NUMBUF_LEN, "%i", i);
2925 newname_len = IDENTIFIER_LENGTH (name)
2926 + strlen (numbuf) + 2;
2927 newname = (char*)alloca (newname_len);
2928 snprintf (newname, newname_len,
2929 "%s#%i", IDENTIFIER_POINTER (name), i);
2930 return get_identifier (newname);
2933 /* Return true if T is a primary function, class or alias template
2937 primary_template_instantiation_p (const_tree t)
2942 if (TREE_CODE (t) == FUNCTION_DECL)
2943 return DECL_LANG_SPECIFIC (t)
2944 && DECL_TEMPLATE_INSTANTIATION (t)
2945 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t));
2946 else if (CLASS_TYPE_P (t) && !TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
2947 return CLASSTYPE_TEMPLATE_INSTANTIATION (t)
2948 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t));
2949 else if (alias_template_specialization_p (t))
2954 /* Return true if PARM is a template template parameter. */
2957 template_template_parameter_p (const_tree parm)
2959 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm);
2962 /* Return true iff PARM is a DECL representing a type template
2966 template_type_parameter_p (const_tree parm)
2969 && (TREE_CODE (parm) == TYPE_DECL
2970 || TREE_CODE (parm) == TEMPLATE_DECL)
2971 && DECL_TEMPLATE_PARM_P (parm));
2974 /* Return the template parameters of T if T is a
2975 primary template instantiation, NULL otherwise. */
2978 get_primary_template_innermost_parameters (const_tree t)
2980 tree parms = NULL, template_info = NULL;
2982 if ((template_info = get_template_info (t))
2983 && primary_template_instantiation_p (t))
2984 parms = INNERMOST_TEMPLATE_PARMS
2985 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info)));
2990 /* Return the template parameters of the LEVELth level from the full list
2991 of template parameters PARMS. */
2994 get_template_parms_at_level (tree parms, int level)
2998 || TREE_CODE (parms) != TREE_LIST
2999 || level > TMPL_PARMS_DEPTH (parms))
3002 for (p = parms; p; p = TREE_CHAIN (p))
3003 if (TMPL_PARMS_DEPTH (p) == level)
3009 /* Returns the template arguments of T if T is a template instantiation,
3013 get_template_innermost_arguments (const_tree t)
3015 tree args = NULL, template_info = NULL;
3017 if ((template_info = get_template_info (t))
3018 && TI_ARGS (template_info))
3019 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info));
3024 /* Return the argument pack elements of T if T is a template argument pack,
3028 get_template_argument_pack_elems (const_tree t)
3030 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK
3031 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK)
3034 return ARGUMENT_PACK_ARGS (t);
3037 /* Structure used to track the progress of find_parameter_packs_r. */
3038 struct find_parameter_pack_data
3040 /* TREE_LIST that will contain all of the parameter packs found by
3042 tree* parameter_packs;
3044 /* Set of AST nodes that have been visited by the traversal. */
3045 struct pointer_set_t *visited;
3048 /* Identifies all of the argument packs that occur in a template
3049 argument and appends them to the TREE_LIST inside DATA, which is a
3050 find_parameter_pack_data structure. This is a subroutine of
3051 make_pack_expansion and uses_parameter_packs. */
3053 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
3056 struct find_parameter_pack_data* ppd =
3057 (struct find_parameter_pack_data*)data;
3058 bool parameter_pack_p = false;
3060 /* Handle type aliases/typedefs. */
3063 && TREE_CODE (TYPE_NAME (t)) == TYPE_DECL
3064 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
3066 if (TYPE_TEMPLATE_INFO (t))
3067 cp_walk_tree (&TYPE_TI_ARGS (t),
3068 &find_parameter_packs_r,
3074 /* Identify whether this is a parameter pack or not. */
3075 switch (TREE_CODE (t))
3077 case TEMPLATE_PARM_INDEX:
3078 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3079 parameter_pack_p = true;
3082 case TEMPLATE_TYPE_PARM:
3083 t = TYPE_MAIN_VARIANT (t);
3084 case TEMPLATE_TEMPLATE_PARM:
3085 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3086 parameter_pack_p = true;
3090 if (FUNCTION_PARAMETER_PACK_P (t))
3092 /* We don't want to walk into the type of a PARM_DECL,
3093 because we don't want to see the type parameter pack. */
3095 parameter_pack_p = true;
3100 parameter_pack_p = true;
3103 /* Not a parameter pack. */
3107 if (parameter_pack_p)
3109 /* Add this parameter pack to the list. */
3110 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
3114 cp_walk_tree (&TYPE_CONTEXT (t),
3115 &find_parameter_packs_r, ppd, ppd->visited);
3117 /* This switch statement will return immediately if we don't find a
3119 switch (TREE_CODE (t))
3121 case TEMPLATE_PARM_INDEX:
3124 case BOUND_TEMPLATE_TEMPLATE_PARM:
3125 /* Check the template itself. */
3126 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
3127 &find_parameter_packs_r, ppd, ppd->visited);
3128 /* Check the template arguments. */
3129 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
3134 case TEMPLATE_TYPE_PARM:
3135 case TEMPLATE_TEMPLATE_PARM:
3142 if (TYPE_PTRMEMFUNC_P (t))
3148 if (TYPE_TEMPLATE_INFO (t))
3149 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)),
3150 &find_parameter_packs_r, ppd, ppd->visited);
3157 cp_walk_tree (&TREE_TYPE (t),
3158 &find_parameter_packs_r, ppd, ppd->visited);
3162 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
3167 case TYPE_PACK_EXPANSION:
3168 case EXPR_PACK_EXPANSION:
3173 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
3178 case IDENTIFIER_NODE:
3179 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
3191 /* Determines if the expression or type T uses any parameter packs. */
3193 uses_parameter_packs (tree t)
3195 tree parameter_packs = NULL_TREE;
3196 struct find_parameter_pack_data ppd;
3197 ppd.parameter_packs = ¶meter_packs;
3198 ppd.visited = pointer_set_create ();
3199 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3200 pointer_set_destroy (ppd.visited);
3201 return parameter_packs != NULL_TREE;
3204 /* Turn ARG, which may be an expression, type, or a TREE_LIST
3205 representation a base-class initializer into a parameter pack
3206 expansion. If all goes well, the resulting node will be an
3207 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
3210 make_pack_expansion (tree arg)
3213 tree parameter_packs = NULL_TREE;
3214 bool for_types = false;
3215 struct find_parameter_pack_data ppd;
3217 if (!arg || arg == error_mark_node)
3220 if (TREE_CODE (arg) == TREE_LIST)
3222 /* The only time we will see a TREE_LIST here is for a base
3223 class initializer. In this case, the TREE_PURPOSE will be a
3224 _TYPE node (representing the base class expansion we're
3225 initializing) and the TREE_VALUE will be a TREE_LIST
3226 containing the initialization arguments.
3228 The resulting expansion looks somewhat different from most
3229 expansions. Rather than returning just one _EXPANSION, we
3230 return a TREE_LIST whose TREE_PURPOSE is a
3231 TYPE_PACK_EXPANSION containing the bases that will be
3232 initialized. The TREE_VALUE will be identical to the
3233 original TREE_VALUE, which is a list of arguments that will
3234 be passed to each base. We do not introduce any new pack
3235 expansion nodes into the TREE_VALUE (although it is possible
3236 that some already exist), because the TREE_PURPOSE and
3237 TREE_VALUE all need to be expanded together with the same
3238 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
3239 resulting TREE_PURPOSE will mention the parameter packs in
3240 both the bases and the arguments to the bases. */
3243 tree parameter_packs = NULL_TREE;
3245 /* Determine which parameter packs will be used by the base
3247 ppd.visited = pointer_set_create ();
3248 ppd.parameter_packs = ¶meter_packs;
3249 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
3252 if (parameter_packs == NULL_TREE)
3254 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
3255 pointer_set_destroy (ppd.visited);
3256 return error_mark_node;
3259 if (TREE_VALUE (arg) != void_type_node)
3261 /* Collect the sets of parameter packs used in each of the
3262 initialization arguments. */
3263 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
3265 /* Determine which parameter packs will be expanded in this
3267 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
3272 pointer_set_destroy (ppd.visited);
3274 /* Create the pack expansion type for the base type. */
3275 purpose = cxx_make_type (TYPE_PACK_EXPANSION);
3276 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
3277 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
3279 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3280 they will rarely be compared to anything. */
3281 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
3283 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
3286 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
3289 /* Build the PACK_EXPANSION_* node. */
3291 ? cxx_make_type (TYPE_PACK_EXPANSION)
3292 : make_node (EXPR_PACK_EXPANSION);
3293 SET_PACK_EXPANSION_PATTERN (result, arg);
3294 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
3296 /* Propagate type and const-expression information. */
3297 TREE_TYPE (result) = TREE_TYPE (arg);
3298 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
3301 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
3302 they will rarely be compared to anything. */
3303 SET_TYPE_STRUCTURAL_EQUALITY (result);
3305 /* Determine which parameter packs will be expanded. */
3306 ppd.parameter_packs = ¶meter_packs;
3307 ppd.visited = pointer_set_create ();
3308 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
3309 pointer_set_destroy (ppd.visited);
3311 /* Make sure we found some parameter packs. */
3312 if (parameter_packs == NULL_TREE)
3315 error ("expansion pattern %<%T%> contains no argument packs", arg);
3317 error ("expansion pattern %<%E%> contains no argument packs", arg);
3318 return error_mark_node;
3320 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
3322 PACK_EXPANSION_LOCAL_P (result) = at_function_scope_p ();
3327 /* Checks T for any "bare" parameter packs, which have not yet been
3328 expanded, and issues an error if any are found. This operation can
3329 only be done on full expressions or types (e.g., an expression
3330 statement, "if" condition, etc.), because we could have expressions like:
3332 foo(f(g(h(args)))...)
3334 where "args" is a parameter pack. check_for_bare_parameter_packs
3335 should not be called for the subexpressions args, h(args),
3336 g(h(args)), or f(g(h(args))), because we would produce erroneous
3339 Returns TRUE and emits an error if there were bare parameter packs,
3340 returns FALSE otherwise. */
3342 check_for_bare_parameter_packs (tree t)
3344 tree parameter_packs = NULL_TREE;
3345 struct find_parameter_pack_data ppd;
3347 if (!processing_template_decl || !t || t == error_mark_node)
3350 if (TREE_CODE (t) == TYPE_DECL)
3353 ppd.parameter_packs = ¶meter_packs;
3354 ppd.visited = pointer_set_create ();
3355 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
3356 pointer_set_destroy (ppd.visited);
3358 if (parameter_packs)
3360 error ("parameter packs not expanded with %<...%>:");
3361 while (parameter_packs)
3363 tree pack = TREE_VALUE (parameter_packs);
3364 tree name = NULL_TREE;
3366 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
3367 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
3368 name = TYPE_NAME (pack);
3369 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
3370 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
3372 name = DECL_NAME (pack);
3375 inform (input_location, " %qD", name);
3377 inform (input_location, " <anonymous>");
3379 parameter_packs = TREE_CHAIN (parameter_packs);
3388 /* Expand any parameter packs that occur in the template arguments in
3391 expand_template_argument_pack (tree args)
3393 tree result_args = NULL_TREE;
3394 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3395 int num_result_args = -1;
3396 int non_default_args_count = -1;
3398 /* First, determine if we need to expand anything, and the number of
3399 slots we'll need. */
3400 for (in_arg = 0; in_arg < nargs; ++in_arg)
3402 tree arg = TREE_VEC_ELT (args, in_arg);
3403 if (arg == NULL_TREE)
3405 if (ARGUMENT_PACK_P (arg))
3407 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3408 if (num_result_args < 0)
3409 num_result_args = in_arg + num_packed;
3411 num_result_args += num_packed;
3415 if (num_result_args >= 0)
3420 /* If no expansion is necessary, we're done. */
3421 if (num_result_args < 0)
3424 /* Expand arguments. */
3425 result_args = make_tree_vec (num_result_args);
3426 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args))
3427 non_default_args_count =
3428 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args);
3429 for (in_arg = 0; in_arg < nargs; ++in_arg)
3431 tree arg = TREE_VEC_ELT (args, in_arg);
3432 if (ARGUMENT_PACK_P (arg))
3434 tree packed = ARGUMENT_PACK_ARGS (arg);
3435 int i, num_packed = TREE_VEC_LENGTH (packed);
3436 for (i = 0; i < num_packed; ++i, ++out_arg)
3437 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3438 if (non_default_args_count > 0)
3439 non_default_args_count += num_packed;
3443 TREE_VEC_ELT (result_args, out_arg) = arg;
3447 if (non_default_args_count >= 0)
3448 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count);
3452 /* Checks if DECL shadows a template parameter.
3454 [temp.local]: A template-parameter shall not be redeclared within its
3455 scope (including nested scopes).
3457 Emits an error and returns TRUE if the DECL shadows a parameter,
3458 returns FALSE otherwise. */
3461 check_template_shadow (tree decl)
3465 /* If we're not in a template, we can't possibly shadow a template
3467 if (!current_template_parms)
3470 /* Figure out what we're shadowing. */
3471 if (TREE_CODE (decl) == OVERLOAD)
3472 decl = OVL_CURRENT (decl);
3473 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3475 /* If there's no previous binding for this name, we're not shadowing
3476 anything, let alone a template parameter. */
3480 /* If we're not shadowing a template parameter, we're done. Note
3481 that OLDDECL might be an OVERLOAD (or perhaps even an
3482 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3484 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3487 /* We check for decl != olddecl to avoid bogus errors for using a
3488 name inside a class. We check TPFI to avoid duplicate errors for
3489 inline member templates. */
3491 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3494 error ("declaration of %q+#D", decl);
3495 error (" shadows template parm %q+#D", olddecl);
3499 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3500 ORIG_LEVEL, DECL, and TYPE. */
3503 build_template_parm_index (int index,
3509 tree t = make_node (TEMPLATE_PARM_INDEX);
3510 TEMPLATE_PARM_IDX (t) = index;
3511 TEMPLATE_PARM_LEVEL (t) = level;
3512 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3513 TEMPLATE_PARM_DECL (t) = decl;
3514 TREE_TYPE (t) = type;
3515 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3516 TREE_READONLY (t) = TREE_READONLY (decl);
3521 /* Find the canonical type parameter for the given template type
3522 parameter. Returns the canonical type parameter, which may be TYPE
3523 if no such parameter existed. */
3526 canonical_type_parameter (tree type)
3529 int idx = TEMPLATE_TYPE_IDX (type);
3530 if (!canonical_template_parms)
3531 vec_alloc (canonical_template_parms, idx+1);
3533 while (canonical_template_parms->length () <= (unsigned)idx)
3534 vec_safe_push (canonical_template_parms, NULL_TREE);
3536 list = (*canonical_template_parms)[idx];
3537 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3538 list = TREE_CHAIN (list);
3541 return TREE_VALUE (list);
3544 (*canonical_template_parms)[idx]
3545 = tree_cons (NULL_TREE, type,
3546 (*canonical_template_parms)[idx]);
3551 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3552 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3553 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3554 new one is created. */
3557 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3558 tsubst_flags_t complain)
3560 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3561 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3562 != TEMPLATE_PARM_LEVEL (index) - levels)
3563 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index))))
3565 tree orig_decl = TEMPLATE_PARM_DECL (index);
3568 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3569 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3570 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3571 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3572 DECL_ARTIFICIAL (decl) = 1;
3573 SET_DECL_TEMPLATE_PARM_P (decl);
3575 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3576 TEMPLATE_PARM_LEVEL (index) - levels,
3577 TEMPLATE_PARM_ORIG_LEVEL (index),
3579 TEMPLATE_PARM_DESCENDANTS (index) = t;
3580 TEMPLATE_PARM_PARAMETER_PACK (t)
3581 = TEMPLATE_PARM_PARAMETER_PACK (index);
3583 /* Template template parameters need this. */
3584 if (TREE_CODE (decl) == TEMPLATE_DECL)
3585 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3586 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3590 return TEMPLATE_PARM_DESCENDANTS (index);
3593 /* Process information from new template parameter PARM and append it
3594 to the LIST being built. This new parameter is a non-type
3595 parameter iff IS_NON_TYPE is true. This new parameter is a
3596 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM
3597 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template
3598 parameter list PARM belongs to. This is used used to create a
3599 proper canonical type for the type of PARM that is to be created,
3600 iff PARM is a type. If the size is not known, this parameter shall
3604 process_template_parm (tree list, location_t parm_loc, tree parm,
3605 bool is_non_type, bool is_parameter_pack)
3612 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3613 defval = TREE_PURPOSE (parm);
3617 tree p = tree_last (list);
3619 if (p && TREE_VALUE (p) != error_mark_node)
3622 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3623 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3625 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3635 parm = TREE_VALUE (parm);
3637 SET_DECL_TEMPLATE_PARM_P (parm);
3639 if (TREE_TYPE (parm) == error_mark_node)
3641 err_parm_list = build_tree_list (defval, parm);
3642 TREE_VALUE (err_parm_list) = error_mark_node;
3643 return chainon (list, err_parm_list);
3649 The top-level cv-qualifiers on the template-parameter are
3650 ignored when determining its type. */
3651 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3652 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3654 err_parm_list = build_tree_list (defval, parm);
3655 TREE_VALUE (err_parm_list) = error_mark_node;
3656 return chainon (list, err_parm_list);
3659 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3661 /* This template parameter is not a parameter pack, but it
3662 should be. Complain about "bare" parameter packs. */
3663 check_for_bare_parameter_packs (TREE_TYPE (parm));
3665 /* Recover by calling this a parameter pack. */
3666 is_parameter_pack = true;
3670 /* A template parameter is not modifiable. */
3671 TREE_CONSTANT (parm) = 1;
3672 TREE_READONLY (parm) = 1;
3673 decl = build_decl (parm_loc,
3674 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3675 TREE_CONSTANT (decl) = 1;
3676 TREE_READONLY (decl) = 1;
3677 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3678 = build_template_parm_index (idx, processing_template_decl,
3679 processing_template_decl,
3680 decl, TREE_TYPE (parm));
3682 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3683 = is_parameter_pack;
3688 parm = TREE_VALUE (TREE_VALUE (parm));
3690 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3692 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3693 /* This is for distinguishing between real templates and template
3694 template parameters */
3695 TREE_TYPE (parm) = t;
3696 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3701 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3702 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3703 decl = build_decl (parm_loc,
3704 TYPE_DECL, parm, t);
3707 TYPE_NAME (t) = decl;
3708 TYPE_STUB_DECL (t) = decl;
3710 TEMPLATE_TYPE_PARM_INDEX (t)
3711 = build_template_parm_index (idx, processing_template_decl,
3712 processing_template_decl,
3713 decl, TREE_TYPE (parm));
3714 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3715 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3717 DECL_ARTIFICIAL (decl) = 1;
3718 SET_DECL_TEMPLATE_PARM_P (decl);
3720 parm = build_tree_list (defval, parm);
3721 return chainon (list, parm);
3724 /* The end of a template parameter list has been reached. Process the
3725 tree list into a parameter vector, converting each parameter into a more
3726 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3730 end_template_parm_list (tree parms)
3734 tree saved_parmlist = make_tree_vec (list_length (parms));
3736 current_template_parms
3737 = tree_cons (size_int (processing_template_decl),
3738 saved_parmlist, current_template_parms);
3740 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3742 next = TREE_CHAIN (parm);
3743 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3744 TREE_CHAIN (parm) = NULL_TREE;
3747 --processing_template_parmlist;
3749 return saved_parmlist;
3752 /* end_template_decl is called after a template declaration is seen. */
3755 end_template_decl (void)
3757 reset_specialization ();
3759 if (! processing_template_decl)
3762 /* This matches the pushlevel in begin_template_parm_list. */
3765 --processing_template_decl;
3766 current_template_parms = TREE_CHAIN (current_template_parms);
3769 /* Takes a TREE_LIST representing a template parameter and convert it
3770 into an argument suitable to be passed to the type substitution
3771 functions. Note that If the TREE_LIST contains an error_mark
3772 node, the returned argument is error_mark_node. */
3775 template_parm_to_arg (tree t)
3779 || TREE_CODE (t) != TREE_LIST)
3782 if (error_operand_p (TREE_VALUE (t)))
3783 return error_mark_node;
3787 if (TREE_CODE (t) == TYPE_DECL
3788 || TREE_CODE (t) == TEMPLATE_DECL)
3792 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3794 /* Turn this argument into a TYPE_ARGUMENT_PACK
3795 with a single element, which expands T. */
3796 tree vec = make_tree_vec (1);
3797 #ifdef ENABLE_CHECKING
3798 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3799 (vec, TREE_VEC_LENGTH (vec));
3801 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3803 t = cxx_make_type (TYPE_ARGUMENT_PACK);
3804 SET_ARGUMENT_PACK_ARGS (t, vec);
3809 t = DECL_INITIAL (t);
3811 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3813 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3814 with a single element, which expands T. */
3815 tree vec = make_tree_vec (1);
3816 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3817 #ifdef ENABLE_CHECKING
3818 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT
3819 (vec, TREE_VEC_LENGTH (vec));
3821 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3823 t = make_node (NONTYPE_ARGUMENT_PACK);
3824 SET_ARGUMENT_PACK_ARGS (t, vec);
3825 TREE_TYPE (t) = type;
3831 /* Given a set of template parameters, return them as a set of template
3832 arguments. The template parameters are represented as a TREE_VEC, in
3833 the form documented in cp-tree.h for template arguments. */
3836 template_parms_to_args (tree parms)
3839 tree args = NULL_TREE;
3840 int length = TMPL_PARMS_DEPTH (parms);
3843 /* If there is only one level of template parameters, we do not
3844 create a TREE_VEC of TREE_VECs. Instead, we return a single
3845 TREE_VEC containing the arguments. */
3847 args = make_tree_vec (length);
3849 for (header = parms; header; header = TREE_CHAIN (header))
3851 tree a = copy_node (TREE_VALUE (header));
3854 TREE_TYPE (a) = NULL_TREE;
3855 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3856 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i));
3858 #ifdef ENABLE_CHECKING
3859 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a));
3863 TREE_VEC_ELT (args, --l) = a;
3868 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE)
3869 /* This can happen for template parms of a template template
3872 template<template<class T, class U> class TT> struct S;
3874 Consider the level of the parms of TT; T and U both have
3875 level 2; TT has no template parm of level 1. So in this case
3876 the first element of full_template_args is NULL_TREE. If we
3877 leave it like this TMPL_ARG_DEPTH on args returns 1 instead
3878 of 2. This will make tsubst wrongly consider that T and U
3879 have level 1. Instead, let's create a dummy vector as the
3880 first element of full_template_args so that TMPL_ARG_DEPTH
3881 returns the correct depth for args. */
3882 TREE_VEC_ELT (args, 0) = make_tree_vec (1);
3886 /* Within the declaration of a template, return the currently active
3887 template parameters as an argument TREE_VEC. */
3890 current_template_args (void)
3892 return template_parms_to_args (current_template_parms);
3895 /* Update the declared TYPE by doing any lookups which were thought to be
3896 dependent, but are not now that we know the SCOPE of the declarator. */
3899 maybe_update_decl_type (tree orig_type, tree scope)
3901 tree type = orig_type;
3903 if (type == NULL_TREE)
3906 if (TREE_CODE (orig_type) == TYPE_DECL)
3907 type = TREE_TYPE (type);
3909 if (scope && TYPE_P (scope) && dependent_type_p (scope)
3910 && dependent_type_p (type)
3911 /* Don't bother building up the args in this case. */
3912 && TREE_CODE (type) != TEMPLATE_TYPE_PARM)
3914 /* tsubst in the args corresponding to the template parameters,
3915 including auto if present. Most things will be unchanged, but
3916 make_typename_type and tsubst_qualified_id will resolve
3917 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */
3918 tree args = current_template_args ();
3919 tree auto_node = type_uses_auto (type);
3923 tree auto_vec = make_tree_vec (1);
3924 TREE_VEC_ELT (auto_vec, 0) = auto_node;
3925 args = add_to_template_args (args, auto_vec);
3927 pushed = push_scope (scope);
3928 type = tsubst (type, args, tf_warning_or_error, NULL_TREE);
3933 if (type == error_mark_node)
3936 if (TREE_CODE (orig_type) == TYPE_DECL)
3938 if (same_type_p (type, TREE_TYPE (orig_type)))
3941 type = TYPE_NAME (type);
3946 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3947 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3948 a member template. Used by push_template_decl below. */
3951 build_template_decl (tree decl, tree parms, bool member_template_p)
3953 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3954 DECL_TEMPLATE_PARMS (tmpl) = parms;
3955 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3956 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
3957 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3962 struct template_parm_data
3964 /* The level of the template parameters we are currently
3968 /* The index of the specialization argument we are currently
3972 /* An array whose size is the number of template parameters. The
3973 elements are nonzero if the parameter has been used in any one
3974 of the arguments processed so far. */
3977 /* An array whose size is the number of template arguments. The
3978 elements are nonzero if the argument makes use of template
3979 parameters of this level. */
3980 int* arg_uses_template_parms;
3983 /* Subroutine of push_template_decl used to see if each template
3984 parameter in a partial specialization is used in the explicit
3985 argument list. If T is of the LEVEL given in DATA (which is
3986 treated as a template_parm_data*), then DATA->PARMS is marked
3990 mark_template_parm (tree t, void* data)
3994 struct template_parm_data* tpd = (struct template_parm_data*) data;
3996 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3998 level = TEMPLATE_PARM_LEVEL (t);
3999 idx = TEMPLATE_PARM_IDX (t);
4003 level = TEMPLATE_TYPE_LEVEL (t);
4004 idx = TEMPLATE_TYPE_IDX (t);
4007 if (level == tpd->level)
4009 tpd->parms[idx] = 1;
4010 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
4013 /* Return zero so that for_each_template_parm will continue the
4014 traversal of the tree; we want to mark *every* template parm. */
4018 /* Process the partial specialization DECL. */
4021 process_partial_specialization (tree decl)
4023 tree type = TREE_TYPE (decl);
4024 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
4025 tree specargs = CLASSTYPE_TI_ARGS (type);
4026 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
4027 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
4030 int nargs = TREE_VEC_LENGTH (inner_args);
4033 bool did_error_intro = false;
4034 struct template_parm_data tpd;
4035 struct template_parm_data tpd2;
4037 gcc_assert (current_template_parms);
4039 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
4040 ntparms = TREE_VEC_LENGTH (inner_parms);
4042 /* We check that each of the template parameters given in the
4043 partial specialization is used in the argument list to the
4044 specialization. For example:
4046 template <class T> struct S;
4047 template <class T> struct S<T*>;
4049 The second declaration is OK because `T*' uses the template
4050 parameter T, whereas
4052 template <class T> struct S<int>;
4054 is no good. Even trickier is:
4065 The S2<T> declaration is actually invalid; it is a
4066 full-specialization. Of course,
4069 struct S2<T (*)(U)>;
4071 or some such would have been OK. */
4072 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
4073 tpd.parms = XALLOCAVEC (int, ntparms);
4074 memset (tpd.parms, 0, sizeof (int) * ntparms);
4076 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4077 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
4078 for (i = 0; i < nargs; ++i)
4080 tpd.current_arg = i;
4081 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
4082 &mark_template_parm,
4085 /*include_nondeduced_p=*/false);
4087 for (i = 0; i < ntparms; ++i)
4088 if (tpd.parms[i] == 0)
4090 /* One of the template parms was not used in the
4092 if (!did_error_intro)
4094 error ("template parameters not used in partial specialization:");
4095 did_error_intro = true;
4098 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
4101 if (did_error_intro)
4102 return error_mark_node;
4104 /* [temp.class.spec]
4106 The argument list of the specialization shall not be identical to
4107 the implicit argument list of the primary template. */
4108 if (comp_template_args
4110 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
4112 error ("partial specialization %qT does not specialize any template arguments", type);
4114 /* A partial specialization that replaces multiple parameters of the
4115 primary template with a pack expansion is less specialized for those
4117 if (nargs < DECL_NTPARMS (maintmpl))
4119 error ("partial specialization is not more specialized than the "
4120 "primary template because it replaces multiple parameters "
4121 "with a pack expansion");
4122 inform (DECL_SOURCE_LOCATION (maintmpl), "primary template here");
4126 /* [temp.class.spec]
4128 A partially specialized non-type argument expression shall not
4129 involve template parameters of the partial specialization except
4130 when the argument expression is a simple identifier.
4132 The type of a template parameter corresponding to a specialized
4133 non-type argument shall not be dependent on a parameter of the
4136 Also, we verify that pack expansions only occur at the
4137 end of the argument list. */
4138 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
4140 for (i = 0; i < nargs; ++i)
4142 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
4143 tree arg = TREE_VEC_ELT (inner_args, i);
4144 tree packed_args = NULL_TREE;
4147 if (ARGUMENT_PACK_P (arg))
4149 /* Extract the arguments from the argument pack. We'll be
4150 iterating over these in the following loop. */
4151 packed_args = ARGUMENT_PACK_ARGS (arg);
4152 len = TREE_VEC_LENGTH (packed_args);
4155 for (j = 0; j < len; j++)
4158 /* Get the Jth argument in the parameter pack. */
4159 arg = TREE_VEC_ELT (packed_args, j);
4161 if (PACK_EXPANSION_P (arg))
4163 /* Pack expansions must come at the end of the
4165 if ((packed_args && j < len - 1)
4166 || (!packed_args && i < nargs - 1))
4168 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4169 error ("parameter pack argument %qE must be at the "
4170 "end of the template argument list", arg);
4172 error ("parameter pack argument %qT must be at the "
4173 "end of the template argument list", arg);
4177 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
4178 /* We only care about the pattern. */
4179 arg = PACK_EXPANSION_PATTERN (arg);
4181 if (/* These first two lines are the `non-type' bit. */
4183 && TREE_CODE (arg) != TEMPLATE_DECL
4184 /* This next line is the `argument expression is not just a
4185 simple identifier' condition and also the `specialized
4186 non-type argument' bit. */
4187 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
4189 if ((!packed_args && tpd.arg_uses_template_parms[i])
4190 || (packed_args && uses_template_parms (arg)))
4191 error ("template argument %qE involves template parameter(s)",
4195 /* Look at the corresponding template parameter,
4196 marking which template parameters its type depends
4198 tree type = TREE_TYPE (parm);
4202 /* We haven't yet initialized TPD2. Do so now. */
4203 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs);
4204 /* The number of parameters here is the number in the
4205 main template, which, as checked in the assertion
4207 tpd2.parms = XALLOCAVEC (int, nargs);
4209 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
4212 /* Mark the template parameters. But this time, we're
4213 looking for the template parameters of the main
4214 template, not in the specialization. */
4215 tpd2.current_arg = i;
4216 tpd2.arg_uses_template_parms[i] = 0;
4217 memset (tpd2.parms, 0, sizeof (int) * nargs);
4218 for_each_template_parm (type,
4219 &mark_template_parm,
4222 /*include_nondeduced_p=*/false);
4224 if (tpd2.arg_uses_template_parms [i])
4226 /* The type depended on some template parameters.
4227 If they are fully specialized in the
4228 specialization, that's OK. */
4231 for (j = 0; j < nargs; ++j)
4232 if (tpd2.parms[j] != 0
4233 && tpd.arg_uses_template_parms [j])
4236 error_n (input_location, count,
4237 "type %qT of template argument %qE depends "
4238 "on a template parameter",
4239 "type %qT of template argument %qE depends "
4240 "on template parameters",
4249 /* We should only get here once. */
4250 gcc_assert (!COMPLETE_TYPE_P (type));
4252 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
4253 = tree_cons (specargs, inner_parms,
4254 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
4255 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
4257 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst;
4258 inst = TREE_CHAIN (inst))
4260 tree inst_type = TREE_VALUE (inst);
4261 if (COMPLETE_TYPE_P (inst_type)
4262 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type))
4264 tree spec = most_specialized_class (inst_type, maintmpl, tf_none);
4265 if (spec && TREE_TYPE (spec) == type)
4266 permerror (input_location,
4267 "partial specialization of %qT after instantiation "
4268 "of %qT", type, inst_type);
4275 /* Check that a template declaration's use of default arguments and
4276 parameter packs is not invalid. Here, PARMS are the template
4277 parameters. IS_PRIMARY is true if DECL is the thing declared by
4278 a primary template. IS_PARTIAL is true if DECL is a partial
4281 IS_FRIEND_DECL is nonzero if DECL is a friend function template
4282 declaration (but not a definition); 1 indicates a declaration, 2
4283 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
4284 emitted for extraneous default arguments.
4286 Returns TRUE if there were no errors found, FALSE otherwise. */
4289 check_default_tmpl_args (tree decl, tree parms, bool is_primary,
4290 bool is_partial, int is_friend_decl)
4293 int last_level_to_check;
4295 bool no_errors = true;
4299 A default template-argument shall not be specified in a
4300 function template declaration or a function template definition, nor
4301 in the template-parameter-list of the definition of a member of a
4304 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
4305 /* You can't have a function template declaration in a local
4306 scope, nor you can you define a member of a class template in a
4310 if (TREE_CODE (decl) == TYPE_DECL
4312 && LAMBDA_TYPE_P (TREE_TYPE (decl)))
4313 /* A lambda doesn't have an explicit declaration; don't complain
4314 about the parms of the enclosing class. */
4317 if (current_class_type
4318 && !TYPE_BEING_DEFINED (current_class_type)
4319 && DECL_LANG_SPECIFIC (decl)
4320 && DECL_DECLARES_FUNCTION_P (decl)
4321 /* If this is either a friend defined in the scope of the class
4322 or a member function. */
4323 && (DECL_FUNCTION_MEMBER_P (decl)
4324 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
4325 : DECL_FRIEND_CONTEXT (decl)
4326 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
4328 /* And, if it was a member function, it really was defined in
4329 the scope of the class. */
4330 && (!DECL_FUNCTION_MEMBER_P (decl)
4331 || DECL_INITIALIZED_IN_CLASS_P (decl)))
4332 /* We already checked these parameters when the template was
4333 declared, so there's no need to do it again now. This function
4334 was defined in class scope, but we're processing it's body now
4335 that the class is complete. */
4338 /* Core issue 226 (C++0x only): the following only applies to class
4341 && ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL))
4345 If a template-parameter has a default template-argument, all
4346 subsequent template-parameters shall have a default
4347 template-argument supplied. */
4348 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
4350 tree inner_parms = TREE_VALUE (parm_level);
4351 int ntparms = TREE_VEC_LENGTH (inner_parms);
4352 int seen_def_arg_p = 0;
4355 for (i = 0; i < ntparms; ++i)
4357 tree parm = TREE_VEC_ELT (inner_parms, i);
4359 if (parm == error_mark_node)
4362 if (TREE_PURPOSE (parm))
4364 else if (seen_def_arg_p
4365 && !template_parameter_pack_p (TREE_VALUE (parm)))
4367 error ("no default argument for %qD", TREE_VALUE (parm));
4368 /* For better subsequent error-recovery, we indicate that
4369 there should have been a default argument. */
4370 TREE_PURPOSE (parm) = error_mark_node;
4373 else if (!is_partial
4375 /* Don't complain about an enclosing partial
4377 && parm_level == parms
4378 && TREE_CODE (decl) == TYPE_DECL
4380 && template_parameter_pack_p (TREE_VALUE (parm)))
4382 /* A primary class template can only have one
4383 parameter pack, at the end of the template
4386 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
4387 error ("parameter pack %qE must be at the end of the"
4388 " template parameter list", TREE_VALUE (parm));
4390 error ("parameter pack %qT must be at the end of the"
4391 " template parameter list",
4392 TREE_TYPE (TREE_VALUE (parm)));
4394 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
4402 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
4406 /* For an ordinary class template, default template arguments are
4407 allowed at the innermost level, e.g.:
4408 template <class T = int>
4410 but, in a partial specialization, they're not allowed even
4411 there, as we have in [temp.class.spec]:
4413 The template parameter list of a specialization shall not
4414 contain default template argument values.
4416 So, for a partial specialization, or for a function template
4417 (in C++98/C++03), we look at all of them. */
4420 /* But, for a primary class template that is not a partial
4421 specialization we look at all template parameters except the
4423 parms = TREE_CHAIN (parms);
4425 /* Figure out what error message to issue. */
4426 if (is_friend_decl == 2)
4427 msg = G_("default template arguments may not be used in function template "
4428 "friend re-declaration");
4429 else if (is_friend_decl)
4430 msg = G_("default template arguments may not be used in function template "
4431 "friend declarations");
4432 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
4433 msg = G_("default template arguments may not be used in function templates "
4434 "without -std=c++11 or -std=gnu++11");
4435 else if (is_partial)
4436 msg = G_("default template arguments may not be used in "
4437 "partial specializations");
4439 msg = G_("default argument for template parameter for class enclosing %qD");
4441 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
4442 /* If we're inside a class definition, there's no need to
4443 examine the parameters to the class itself. On the one
4444 hand, they will be checked when the class is defined, and,
4445 on the other, default arguments are valid in things like:
4446 template <class T = double>
4447 struct S { template <class U> void f(U); };
4448 Here the default argument for `S' has no bearing on the
4449 declaration of `f'. */
4450 last_level_to_check = template_class_depth (current_class_type) + 1;
4452 /* Check everything. */
4453 last_level_to_check = 0;
4455 for (parm_level = parms;
4456 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
4457 parm_level = TREE_CHAIN (parm_level))
4459 tree inner_parms = TREE_VALUE (parm_level);
4463 ntparms = TREE_VEC_LENGTH (inner_parms);
4464 for (i = 0; i < ntparms; ++i)
4466 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
4469 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
4474 if (is_friend_decl == 2)
4481 /* Clear out the default argument so that we are not
4483 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
4487 /* At this point, if we're still interested in issuing messages,
4488 they must apply to classes surrounding the object declared. */
4490 msg = G_("default argument for template parameter for class "
4497 /* Worker for push_template_decl_real, called via
4498 for_each_template_parm. DATA is really an int, indicating the
4499 level of the parameters we are interested in. If T is a template
4500 parameter of that level, return nonzero. */
4503 template_parm_this_level_p (tree t, void* data)
4505 int this_level = *(int *)data;
4508 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
4509 level = TEMPLATE_PARM_LEVEL (t);
4511 level = TEMPLATE_TYPE_LEVEL (t);
4512 return level == this_level;
4515 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
4516 parameters given by current_template_args, or reuses a
4517 previously existing one, if appropriate. Returns the DECL, or an
4518 equivalent one, if it is replaced via a call to duplicate_decls.
4520 If IS_FRIEND is true, DECL is a friend declaration. */
4523 push_template_decl_real (tree decl, bool is_friend)
4531 int new_template_p = 0;
4532 /* True if the template is a member template, in the sense of
4534 bool member_template_p = false;
4536 if (decl == error_mark_node || !current_template_parms)
4537 return error_mark_node;
4539 /* See if this is a partial specialization. */
4540 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4541 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4542 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4544 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4548 /* For a friend, we want the context of the friend function, not
4549 the type of which it is a friend. */
4550 ctx = CP_DECL_CONTEXT (decl);
4551 else if (CP_DECL_CONTEXT (decl)
4552 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4553 /* In the case of a virtual function, we want the class in which
4555 ctx = CP_DECL_CONTEXT (decl);
4557 /* Otherwise, if we're currently defining some class, the DECL
4558 is assumed to be a member of the class. */
4559 ctx = current_scope ();
4561 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4564 if (!DECL_CONTEXT (decl))
4565 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4567 /* See if this is a primary template. */
4568 if (is_friend && ctx)
4569 /* A friend template that specifies a class context, i.e.
4570 template <typename T> friend void A<T>::f();
4574 is_primary = template_parm_scope_p ();
4578 if (DECL_CLASS_SCOPE_P (decl))
4579 member_template_p = true;
4580 if (TREE_CODE (decl) == TYPE_DECL
4581 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4583 error ("template class without a name");
4584 return error_mark_node;
4586 else if (TREE_CODE (decl) == FUNCTION_DECL)
4588 if (DECL_DESTRUCTOR_P (decl))
4592 A destructor shall not be a member template. */
4593 error ("destructor %qD declared as member template", decl);
4594 return error_mark_node;
4596 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4597 && (!prototype_p (TREE_TYPE (decl))
4598 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4599 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4600 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4601 == void_list_node)))
4603 /* [basic.stc.dynamic.allocation]
4605 An allocation function can be a function
4606 template. ... Template allocation functions shall
4607 have two or more parameters. */
4608 error ("invalid template declaration of %qD", decl);
4609 return error_mark_node;
4612 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4613 && CLASS_TYPE_P (TREE_TYPE (decl)))
4615 else if (TREE_CODE (decl) == TYPE_DECL
4616 && TYPE_DECL_ALIAS_P (decl))
4617 /* alias-declaration */
4618 gcc_assert (!DECL_ARTIFICIAL (decl));
4621 error ("template declaration of %q#D", decl);
4622 return error_mark_node;
4626 /* Check to see that the rules regarding the use of default
4627 arguments are not being violated. */
4628 check_default_tmpl_args (decl, current_template_parms,
4629 is_primary, is_partial, /*is_friend_decl=*/0);
4631 /* Ensure that there are no parameter packs in the type of this
4632 declaration that have not been expanded. */
4633 if (TREE_CODE (decl) == FUNCTION_DECL)
4635 /* Check each of the arguments individually to see if there are
4636 any bare parameter packs. */
4637 tree type = TREE_TYPE (decl);
4638 tree arg = DECL_ARGUMENTS (decl);
4639 tree argtype = TYPE_ARG_TYPES (type);
4641 while (arg && argtype)
4643 if (!FUNCTION_PARAMETER_PACK_P (arg)
4644 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4646 /* This is a PARM_DECL that contains unexpanded parameter
4647 packs. We have already complained about this in the
4648 check_for_bare_parameter_packs call, so just replace
4649 these types with ERROR_MARK_NODE. */
4650 TREE_TYPE (arg) = error_mark_node;
4651 TREE_VALUE (argtype) = error_mark_node;
4654 arg = DECL_CHAIN (arg);
4655 argtype = TREE_CHAIN (argtype);
4658 /* Check for bare parameter packs in the return type and the
4659 exception specifiers. */
4660 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4661 /* Errors were already issued, set return type to int
4662 as the frontend doesn't expect error_mark_node as
4664 TREE_TYPE (type) = integer_type_node;
4665 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4666 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4668 else if (check_for_bare_parameter_packs ((TREE_CODE (decl) == TYPE_DECL
4669 && TYPE_DECL_ALIAS_P (decl))
4670 ? DECL_ORIGINAL_TYPE (decl)
4671 : TREE_TYPE (decl)))
4673 TREE_TYPE (decl) = error_mark_node;
4674 return error_mark_node;
4678 return process_partial_specialization (decl);
4680 args = current_template_args ();
4683 || TREE_CODE (ctx) == FUNCTION_DECL
4684 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4685 || (TREE_CODE (decl) == TYPE_DECL
4686 && LAMBDA_TYPE_P (TREE_TYPE (decl)))
4687 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4689 if (DECL_LANG_SPECIFIC (decl)
4690 && DECL_TEMPLATE_INFO (decl)
4691 && DECL_TI_TEMPLATE (decl))
4692 tmpl = DECL_TI_TEMPLATE (decl);
4693 /* If DECL is a TYPE_DECL for a class-template, then there won't
4694 be DECL_LANG_SPECIFIC. The information equivalent to
4695 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4696 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4697 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4698 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4700 /* Since a template declaration already existed for this
4701 class-type, we must be redeclaring it here. Make sure
4702 that the redeclaration is valid. */
4703 redeclare_class_template (TREE_TYPE (decl),
4704 current_template_parms);
4705 /* We don't need to create a new TEMPLATE_DECL; just use the
4706 one we already had. */
4707 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4711 tmpl = build_template_decl (decl, current_template_parms,
4715 if (DECL_LANG_SPECIFIC (decl)
4716 && DECL_TEMPLATE_SPECIALIZATION (decl))
4718 /* A specialization of a member template of a template
4720 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4721 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4722 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4728 tree a, t, current, parms;
4730 tree tinfo = get_template_info (decl);
4734 error ("template definition of non-template %q#D", decl);
4735 return error_mark_node;
4738 tmpl = TI_TEMPLATE (tinfo);
4740 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4741 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4742 && DECL_TEMPLATE_SPECIALIZATION (decl)
4743 && DECL_MEMBER_TEMPLATE_P (tmpl))
4747 /* The declaration is a specialization of a member
4748 template, declared outside the class. Therefore, the
4749 innermost template arguments will be NULL, so we
4750 replace them with the arguments determined by the
4751 earlier call to check_explicit_specialization. */
4752 args = DECL_TI_ARGS (decl);
4755 = build_template_decl (decl, current_template_parms,
4757 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4758 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4759 DECL_TI_TEMPLATE (decl) = new_tmpl;
4760 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4761 DECL_TEMPLATE_INFO (new_tmpl)
4762 = build_template_info (tmpl, args);
4764 register_specialization (new_tmpl,
4765 most_general_template (tmpl),
4771 /* Make sure the template headers we got make sense. */
4773 parms = DECL_TEMPLATE_PARMS (tmpl);
4774 i = TMPL_PARMS_DEPTH (parms);
4775 if (TMPL_ARGS_DEPTH (args) != i)
4777 error ("expected %d levels of template parms for %q#D, got %d",
4778 i, decl, TMPL_ARGS_DEPTH (args));
4781 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4783 a = TMPL_ARGS_LEVEL (args, i);
4784 t = INNERMOST_TEMPLATE_PARMS (parms);
4786 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4788 if (current == decl)
4789 error ("got %d template parameters for %q#D",
4790 TREE_VEC_LENGTH (a), decl);
4792 error ("got %d template parameters for %q#T",
4793 TREE_VEC_LENGTH (a), current);
4794 error (" but %d required", TREE_VEC_LENGTH (t));
4795 /* Avoid crash in import_export_decl. */
4796 DECL_INTERFACE_KNOWN (decl) = 1;
4797 return error_mark_node;
4800 if (current == decl)
4802 else if (current == NULL_TREE)
4803 /* Can happen in erroneous input. */
4806 current = (TYPE_P (current)
4807 ? TYPE_CONTEXT (current)
4808 : DECL_CONTEXT (current));
4811 /* Check that the parms are used in the appropriate qualifying scopes
4812 in the declarator. */
4813 if (!comp_template_args
4815 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4818 template arguments to %qD do not match original template %qD",
4819 decl, DECL_TEMPLATE_RESULT (tmpl));
4820 if (!uses_template_parms (TI_ARGS (tinfo)))
4821 inform (input_location, "use template<> for an explicit specialization");
4822 /* Avoid crash in import_export_decl. */
4823 DECL_INTERFACE_KNOWN (decl) = 1;
4824 return error_mark_node;
4828 DECL_TEMPLATE_RESULT (tmpl) = decl;
4829 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4831 /* Push template declarations for global functions and types. Note
4832 that we do not try to push a global template friend declared in a
4833 template class; such a thing may well depend on the template
4834 parameters of the class. */
4835 if (new_template_p && !ctx
4836 && !(is_friend && template_class_depth (current_class_type) > 0))
4838 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4839 if (tmpl == error_mark_node)
4840 return error_mark_node;
4842 /* Hide template friend classes that haven't been declared yet. */
4843 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4845 DECL_ANTICIPATED (tmpl) = 1;
4846 DECL_FRIEND_P (tmpl) = 1;
4852 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4855 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4856 if (DECL_CONV_FN_P (tmpl))
4858 int depth = TMPL_PARMS_DEPTH (parms);
4860 /* It is a conversion operator. See if the type converted to
4861 depends on innermost template operands. */
4863 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4865 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4868 /* Give template template parms a DECL_CONTEXT of the template
4869 for which they are a parameter. */
4870 parms = INNERMOST_TEMPLATE_PARMS (parms);
4871 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4873 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4874 if (TREE_CODE (parm) == TEMPLATE_DECL)
4875 DECL_CONTEXT (parm) = tmpl;
4879 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4880 back to its most general template. If TMPL is a specialization,
4881 ARGS may only have the innermost set of arguments. Add the missing
4882 argument levels if necessary. */
4883 if (DECL_TEMPLATE_INFO (tmpl))
4884 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4886 info = build_template_info (tmpl, args);
4888 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4889 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4892 if (is_primary && !DECL_LANG_SPECIFIC (decl))
4893 retrofit_lang_decl (decl);
4894 if (DECL_LANG_SPECIFIC (decl))
4895 DECL_TEMPLATE_INFO (decl) = info;
4898 return DECL_TEMPLATE_RESULT (tmpl);
4902 push_template_decl (tree decl)
4904 return push_template_decl_real (decl, false);
4907 /* FN is an inheriting constructor that inherits from the constructor
4908 template INHERITED; turn FN into a constructor template with a matching
4912 add_inherited_template_parms (tree fn, tree inherited)
4915 = INNERMOST_TEMPLATE_PARMS (DECL_TEMPLATE_PARMS (inherited));
4916 inner_parms = copy_node (inner_parms);
4918 = tree_cons (size_int (processing_template_decl + 1),
4919 inner_parms, current_template_parms);
4920 tree tmpl = build_template_decl (fn, parms, /*member*/true);
4921 tree args = template_parms_to_args (parms);
4922 DECL_TEMPLATE_INFO (fn) = build_template_info (tmpl, args);
4923 TREE_TYPE (tmpl) = TREE_TYPE (fn);
4924 DECL_TEMPLATE_RESULT (tmpl) = fn;
4925 DECL_ARTIFICIAL (tmpl) = true;
4926 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4930 /* Called when a class template TYPE is redeclared with the indicated
4931 template PARMS, e.g.:
4933 template <class T> struct S;
4934 template <class T> struct S {}; */
4937 redeclare_class_template (tree type, tree parms)
4943 if (!TYPE_TEMPLATE_INFO (type))
4945 error ("%qT is not a template type", type);
4949 tmpl = TYPE_TI_TEMPLATE (type);
4950 if (!PRIMARY_TEMPLATE_P (tmpl))
4951 /* The type is nested in some template class. Nothing to worry
4952 about here; there are no new template parameters for the nested
4958 error ("template specifiers not specified in declaration of %qD",
4963 parms = INNERMOST_TEMPLATE_PARMS (parms);
4964 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4966 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4968 error_n (input_location, TREE_VEC_LENGTH (parms),
4969 "redeclared with %d template parameter",
4970 "redeclared with %d template parameters",
4971 TREE_VEC_LENGTH (parms));
4972 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms),
4973 "previous declaration %q+D used %d template parameter",
4974 "previous declaration %q+D used %d template parameters",
4975 tmpl, TREE_VEC_LENGTH (tmpl_parms));
4979 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4986 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4987 || TREE_VEC_ELT (parms, i) == error_mark_node)
4990 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4991 if (tmpl_parm == error_mark_node)
4994 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4995 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4996 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4998 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
5000 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
5001 || (TREE_CODE (tmpl_parm) != TYPE_DECL
5002 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
5003 || (TREE_CODE (tmpl_parm) != PARM_DECL
5004 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
5005 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
5006 || (TREE_CODE (tmpl_parm) == PARM_DECL
5007 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
5008 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))))
5010 error ("template parameter %q+#D", tmpl_parm);
5011 error ("redeclared here as %q#D", parm);
5015 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
5017 /* We have in [temp.param]:
5019 A template-parameter may not be given default arguments
5020 by two different declarations in the same scope. */
5021 error_at (input_location, "redefinition of default argument for %q#D", parm);
5022 inform (DECL_SOURCE_LOCATION (tmpl_parm),
5023 "original definition appeared here");
5027 if (parm_default != NULL_TREE)
5028 /* Update the previous template parameters (which are the ones
5029 that will really count) with the new default value. */
5030 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
5031 else if (tmpl_default != NULL_TREE)
5032 /* Update the new parameters, too; they'll be used as the
5033 parameters for any members. */
5034 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
5040 /* Simplify EXPR if it is a non-dependent expression. Returns the
5041 (possibly simplified) expression. */
5044 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain)
5046 if (expr == NULL_TREE)
5049 /* If we're in a template, but EXPR isn't value dependent, simplify
5050 it. We're supposed to treat:
5052 template <typename T> void f(T[1 + 1]);
5053 template <typename T> void f(T[2]);
5055 as two declarations of the same function, for example. */
5056 if (processing_template_decl
5057 && !type_dependent_expression_p (expr)
5058 && potential_constant_expression (expr)
5059 && !value_dependent_expression_p (expr))
5061 HOST_WIDE_INT saved_processing_template_decl;
5063 saved_processing_template_decl = processing_template_decl;
5064 processing_template_decl = 0;
5065 expr = tsubst_copy_and_build (expr,
5068 /*in_decl=*/NULL_TREE,
5069 /*function_p=*/false,
5070 /*integral_constant_expression_p=*/true);
5071 processing_template_decl = saved_processing_template_decl;
5077 fold_non_dependent_expr (tree expr)
5079 return fold_non_dependent_expr_sfinae (expr, tf_error);
5082 /* Return TRUE iff T is a type alias, a TEMPLATE_DECL for an alias
5083 template declaration, or a TYPE_DECL for an alias declaration. */
5086 alias_type_or_template_p (tree t)
5090 return ((TREE_CODE (t) == TYPE_DECL && TYPE_DECL_ALIAS_P (t))
5093 && TYPE_DECL_ALIAS_P (TYPE_NAME (t)))
5094 || DECL_ALIAS_TEMPLATE_P (t));
5097 /* Return TRUE iff is a specialization of an alias template. */
5100 alias_template_specialization_p (const_tree t)
5106 && TYPE_TEMPLATE_INFO (t)
5107 && PRIMARY_TEMPLATE_P (TYPE_TI_TEMPLATE (t))
5108 && DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (t)));
5111 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
5112 must be a function or a pointer-to-function type, as specified
5113 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
5114 and check that the resulting function has external linkage. */
5117 convert_nontype_argument_function (tree type, tree expr)
5121 linkage_kind linkage;
5123 fn = instantiate_type (type, fns, tf_none);
5124 if (fn == error_mark_node)
5125 return error_mark_node;
5128 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
5129 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
5130 if (BASELINK_P (fn_no_ptr))
5131 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
5133 /* [temp.arg.nontype]/1
5135 A template-argument for a non-type, non-template template-parameter
5138 -- the address of an object or function with external [C++11: or
5139 internal] linkage. */
5141 if (TREE_CODE (fn_no_ptr) != FUNCTION_DECL)
5143 error ("%qE is not a valid template argument for type %qT", expr, type);
5144 if (TREE_CODE (type) == POINTER_TYPE)
5145 error ("it must be the address of a function with external linkage");
5147 error ("it must be the name of a function with external linkage");
5151 linkage = decl_linkage (fn_no_ptr);
5152 if (cxx_dialect >= cxx0x ? linkage == lk_none : linkage != lk_external)
5154 if (cxx_dialect >= cxx0x)
5155 error ("%qE is not a valid template argument for type %qT "
5156 "because %qD has no linkage",
5157 expr, type, fn_no_ptr);
5159 error ("%qE is not a valid template argument for type %qT "
5160 "because %qD does not have external linkage",
5161 expr, type, fn_no_ptr);
5168 /* Subroutine of convert_nontype_argument.
5169 Check if EXPR of type TYPE is a valid pointer-to-member constant.
5170 Emit an error otherwise. */
5173 check_valid_ptrmem_cst_expr (tree type, tree expr,
5174 tsubst_flags_t complain)
5177 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST))
5179 if (cxx_dialect >= cxx0x && null_member_pointer_value_p (expr))
5181 if (complain & tf_error)
5183 error ("%qE is not a valid template argument for type %qT",
5185 error ("it must be a pointer-to-member of the form %<&X::Y%>");
5190 /* Returns TRUE iff the address of OP is value-dependent.
5192 14.6.2.4 [temp.dep.temp]:
5193 A non-integral non-type template-argument is dependent if its type is
5194 dependent or it has either of the following forms
5197 and contains a nested-name-specifier which specifies a class-name that
5198 names a dependent type.
5200 We generalize this to just say that the address of a member of a
5201 dependent class is value-dependent; the above doesn't cover the
5202 address of a static data member named with an unqualified-id. */
5205 has_value_dependent_address (tree op)
5207 /* We could use get_inner_reference here, but there's no need;
5208 this is only relevant for template non-type arguments, which
5209 can only be expressed as &id-expression. */
5212 tree ctx = CP_DECL_CONTEXT (op);
5213 if (TYPE_P (ctx) && dependent_type_p (ctx))
5220 /* The next set of functions are used for providing helpful explanatory
5221 diagnostics for failed overload resolution. Their messages should be
5222 indented by two spaces for consistency with the messages in
5226 unify_success (bool /*explain_p*/)
5232 unify_parameter_deduction_failure (bool explain_p, tree parm)
5235 inform (input_location,
5236 " couldn't deduce template parameter %qD", parm);
5241 unify_invalid (bool /*explain_p*/)
5247 unify_cv_qual_mismatch (bool explain_p, tree parm, tree arg)
5250 inform (input_location,
5251 " types %qT and %qT have incompatible cv-qualifiers",
5257 unify_type_mismatch (bool explain_p, tree parm, tree arg)
5260 inform (input_location, " mismatched types %qT and %qT", parm, arg);
5265 unify_parameter_pack_mismatch (bool explain_p, tree parm, tree arg)
5268 inform (input_location,
5269 " template parameter %qD is not a parameter pack, but "
5276 unify_ptrmem_cst_mismatch (bool explain_p, tree parm, tree arg)
5279 inform (input_location,
5280 " template argument %qE does not match "
5281 "pointer-to-member constant %qE",
5287 unify_expression_unequal (bool explain_p, tree parm, tree arg)
5290 inform (input_location, " %qE is not equivalent to %qE", parm, arg);
5295 unify_parameter_pack_inconsistent (bool explain_p, tree old_arg, tree new_arg)
5298 inform (input_location,
5299 " inconsistent parameter pack deduction with %qT and %qT",
5305 unify_inconsistency (bool explain_p, tree parm, tree first, tree second)
5310 inform (input_location,
5311 " deduced conflicting types for parameter %qT (%qT and %qT)",
5312 parm, first, second);
5314 inform (input_location,
5315 " deduced conflicting values for non-type parameter "
5316 "%qE (%qE and %qE)", parm, first, second);
5322 unify_vla_arg (bool explain_p, tree arg)
5325 inform (input_location,
5326 " variable-sized array type %qT is not "
5327 "a valid template argument",
5333 unify_method_type_error (bool explain_p, tree arg)
5336 inform (input_location,
5337 " member function type %qT is not a valid template argument",
5343 unify_arity (bool explain_p, int have, int wanted)
5346 inform_n (input_location, wanted,
5347 " candidate expects %d argument, %d provided",
5348 " candidate expects %d arguments, %d provided",
5354 unify_too_many_arguments (bool explain_p, int have, int wanted)
5356 return unify_arity (explain_p, have, wanted);
5360 unify_too_few_arguments (bool explain_p, int have, int wanted)
5362 return unify_arity (explain_p, have, wanted);
5366 unify_arg_conversion (bool explain_p, tree to_type,
5367 tree from_type, tree arg)
5370 inform (input_location, " cannot convert %qE (type %qT) to type %qT",
5371 arg, from_type, to_type);
5376 unify_no_common_base (bool explain_p, enum template_base_result r,
5377 tree parm, tree arg)
5382 case tbr_ambiguous_baseclass:
5383 inform (input_location, " %qT is an ambiguous base class of %qT",
5387 inform (input_location, " %qT is not derived from %qT", arg, parm);
5394 unify_inconsistent_template_template_parameters (bool explain_p)
5397 inform (input_location,
5398 " template parameters of a template template argument are "
5399 "inconsistent with other deduced template arguments");
5404 unify_template_deduction_failure (bool explain_p, tree parm, tree arg)
5407 inform (input_location,
5408 " can't deduce a template for %qT from non-template type %qT",
5414 unify_template_argument_mismatch (bool explain_p, tree parm, tree arg)
5417 inform (input_location,
5418 " template argument %qE does not match %qD", arg, parm);
5423 unify_overload_resolution_failure (bool explain_p, tree arg)
5426 inform (input_location,
5427 " could not resolve address from overloaded function %qE",
5432 /* Attempt to convert the non-type template parameter EXPR to the
5433 indicated TYPE. If the conversion is successful, return the
5434 converted value. If the conversion is unsuccessful, return
5435 NULL_TREE if we issued an error message, or error_mark_node if we
5436 did not. We issue error messages for out-and-out bad template
5437 parameters, but not simply because the conversion failed, since we
5438 might be just trying to do argument deduction. Both TYPE and EXPR
5439 must be non-dependent.
5441 The conversion follows the special rules described in
5442 [temp.arg.nontype], and it is much more strict than an implicit
5445 This function is called twice for each template argument (see
5446 lookup_template_class for a more accurate description of this
5447 problem). This means that we need to handle expressions which
5448 are not valid in a C++ source, but can be created from the
5449 first call (for instance, casts to perform conversions). These
5450 hacks can go away after we fix the double coercion problem. */
5453 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain)
5457 /* Detect immediately string literals as invalid non-type argument.
5458 This special-case is not needed for correctness (we would easily
5459 catch this later), but only to provide better diagnostic for this
5460 common user mistake. As suggested by DR 100, we do not mention
5461 linkage issues in the diagnostic as this is not the point. */
5462 /* FIXME we're making this OK. */
5463 if (TREE_CODE (expr) == STRING_CST)
5465 if (complain & tf_error)
5466 error ("%qE is not a valid template argument for type %qT "
5467 "because string literals can never be used in this context",
5472 /* Add the ADDR_EXPR now for the benefit of
5473 value_dependent_expression_p. */
5474 if (TYPE_PTROBV_P (type)
5475 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE)
5477 expr = decay_conversion (expr, complain);
5478 if (expr == error_mark_node)
5479 return error_mark_node;
5482 /* If we are in a template, EXPR may be non-dependent, but still
5483 have a syntactic, rather than semantic, form. For example, EXPR
5484 might be a SCOPE_REF, rather than the VAR_DECL to which the
5485 SCOPE_REF refers. Preserving the qualifying scope is necessary
5486 so that access checking can be performed when the template is
5487 instantiated -- but here we need the resolved form so that we can
5488 convert the argument. */
5489 if (TYPE_REF_OBJ_P (type)
5490 && has_value_dependent_address (expr))
5491 /* If we want the address and it's value-dependent, don't fold. */;
5492 else if (!type_unknown_p (expr))
5493 expr = fold_non_dependent_expr_sfinae (expr, complain);
5494 if (error_operand_p (expr))
5495 return error_mark_node;
5496 expr_type = TREE_TYPE (expr);
5497 if (TREE_CODE (type) == REFERENCE_TYPE)
5498 expr = mark_lvalue_use (expr);
5500 expr = mark_rvalue_use (expr);
5502 /* 14.3.2/5: The null pointer{,-to-member} conversion is applied
5503 to a non-type argument of "nullptr". */
5504 if (expr == nullptr_node && TYPE_PTR_OR_PTRMEM_P (type))
5505 expr = convert (type, expr);
5507 /* In C++11, integral or enumeration non-type template arguments can be
5508 arbitrary constant expressions. Pointer and pointer to
5509 member arguments can be general constant expressions that evaluate
5510 to a null value, but otherwise still need to be of a specific form. */
5511 if (cxx_dialect >= cxx0x)
5513 if (TREE_CODE (expr) == PTRMEM_CST)
5514 /* A PTRMEM_CST is already constant, and a valid template
5515 argument for a parameter of pointer to member type, we just want
5516 to leave it in that form rather than lower it to a
5518 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5519 expr = maybe_constant_value (expr);
5520 else if (TYPE_PTR_OR_PTRMEM_P (type))
5522 tree folded = maybe_constant_value (expr);
5523 if (TYPE_PTR_P (type) ? integer_zerop (folded)
5524 : null_member_pointer_value_p (folded))
5529 /* HACK: Due to double coercion, we can get a
5530 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
5531 which is the tree that we built on the first call (see
5532 below when coercing to reference to object or to reference to
5533 function). We just strip everything and get to the arg.
5534 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
5536 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
5538 tree probe_type, probe = expr;
5539 if (REFERENCE_REF_P (probe))
5540 probe = TREE_OPERAND (probe, 0);
5541 probe_type = TREE_TYPE (probe);
5542 if (TREE_CODE (probe) == NOP_EXPR)
5544 /* ??? Maybe we could use convert_from_reference here, but we
5545 would need to relax its constraints because the NOP_EXPR
5546 could actually change the type to something more cv-qualified,
5547 and this is not folded by convert_from_reference. */
5548 tree addr = TREE_OPERAND (probe, 0);
5549 if (TREE_CODE (probe_type) == REFERENCE_TYPE
5550 && TREE_CODE (addr) == ADDR_EXPR
5551 && TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE
5552 && (same_type_ignoring_top_level_qualifiers_p
5553 (TREE_TYPE (probe_type),
5554 TREE_TYPE (TREE_TYPE (addr)))))
5556 expr = TREE_OPERAND (addr, 0);
5557 expr_type = TREE_TYPE (expr);
5562 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
5563 parameter is a pointer to object, through decay and
5564 qualification conversion. Let's strip everything. */
5565 else if (TREE_CODE (expr) == NOP_EXPR && TYPE_PTROBV_P (type))
5568 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
5569 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
5570 /* Skip the ADDR_EXPR only if it is part of the decay for
5571 an array. Otherwise, it is part of the original argument
5572 in the source code. */
5573 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
5574 expr = TREE_OPERAND (expr, 0);
5575 expr_type = TREE_TYPE (expr);
5578 /* [temp.arg.nontype]/5, bullet 1
5580 For a non-type template-parameter of integral or enumeration type,
5581 integral promotions (_conv.prom_) and integral conversions
5582 (_conv.integral_) are applied. */
5583 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5585 tree t = build_integral_nontype_arg_conv (type, expr, complain);
5586 t = maybe_constant_value (t);
5587 if (t != error_mark_node)
5590 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr)))
5591 return error_mark_node;
5593 /* Notice that there are constant expressions like '4 % 0' which
5594 do not fold into integer constants. */
5595 if (TREE_CODE (expr) != INTEGER_CST)
5597 if (complain & tf_error)
5599 int errs = errorcount, warns = warningcount;
5600 if (processing_template_decl
5601 && !require_potential_constant_expression (expr))
5603 expr = cxx_constant_value (expr);
5604 if (errorcount > errs || warningcount > warns)
5605 inform (EXPR_LOC_OR_HERE (expr),
5606 "in template argument for type %qT ", type);
5607 if (expr == error_mark_node)
5609 /* else cxx_constant_value complained but gave us
5610 a real constant, so go ahead. */
5611 gcc_assert (TREE_CODE (expr) == INTEGER_CST);
5617 /* Avoid typedef problems. */
5618 if (TREE_TYPE (expr) != type)
5619 expr = fold_convert (type, expr);
5621 /* [temp.arg.nontype]/5, bullet 2
5623 For a non-type template-parameter of type pointer to object,
5624 qualification conversions (_conv.qual_) and the array-to-pointer
5625 conversion (_conv.array_) are applied. */
5626 else if (TYPE_PTROBV_P (type))
5628 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
5630 A template-argument for a non-type, non-template template-parameter
5631 shall be one of: [...]
5633 -- the name of a non-type template-parameter;
5634 -- the address of an object or function with external linkage, [...]
5635 expressed as "& id-expression" where the & is optional if the name
5636 refers to a function or array, or if the corresponding
5637 template-parameter is a reference.
5639 Here, we do not care about functions, as they are invalid anyway
5640 for a parameter of type pointer-to-object. */
5642 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
5643 /* Non-type template parameters are OK. */
5645 else if (cxx_dialect >= cxx0x && integer_zerop (expr))
5646 /* Null pointer values are OK in C++11. */;
5647 else if (TREE_CODE (expr) != ADDR_EXPR
5648 && TREE_CODE (expr_type) != ARRAY_TYPE)
5650 if (TREE_CODE (expr) == VAR_DECL)
5652 error ("%qD is not a valid template argument "
5653 "because %qD is a variable, not the address of "
5658 /* Other values, like integer constants, might be valid
5659 non-type arguments of some other type. */
5660 return error_mark_node;
5666 decl = ((TREE_CODE (expr) == ADDR_EXPR)
5667 ? TREE_OPERAND (expr, 0) : expr);
5668 if (TREE_CODE (decl) != VAR_DECL)
5670 error ("%qE is not a valid template argument of type %qT "
5671 "because %qE is not a variable",
5675 else if (cxx_dialect < cxx0x && !DECL_EXTERNAL_LINKAGE_P (decl))
5677 error ("%qE is not a valid template argument of type %qT "
5678 "because %qD does not have external linkage",
5682 else if (cxx_dialect >= cxx0x && decl_linkage (decl) == lk_none)
5684 error ("%qE is not a valid template argument of type %qT "
5685 "because %qD has no linkage",
5691 expr = decay_conversion (expr, complain);
5692 if (expr == error_mark_node)
5693 return error_mark_node;
5695 expr = perform_qualification_conversions (type, expr);
5696 if (expr == error_mark_node)
5697 return error_mark_node;
5699 /* [temp.arg.nontype]/5, bullet 3
5701 For a non-type template-parameter of type reference to object, no
5702 conversions apply. The type referred to by the reference may be more
5703 cv-qualified than the (otherwise identical) type of the
5704 template-argument. The template-parameter is bound directly to the
5705 template-argument, which must be an lvalue. */
5706 else if (TYPE_REF_OBJ_P (type))
5708 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
5710 return error_mark_node;
5712 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
5714 error ("%qE is not a valid template argument for type %qT "
5715 "because of conflicts in cv-qualification", expr, type);
5719 if (!real_lvalue_p (expr))
5721 error ("%qE is not a valid template argument for type %qT "
5722 "because it is not an lvalue", expr, type);
5726 /* [temp.arg.nontype]/1
5728 A template-argument for a non-type, non-template template-parameter
5729 shall be one of: [...]
5731 -- the address of an object or function with external linkage. */
5732 if (TREE_CODE (expr) == INDIRECT_REF
5733 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0))))
5735 expr = TREE_OPERAND (expr, 0);
5738 error ("%q#D is not a valid template argument for type %qT "
5739 "because a reference variable does not have a constant "
5740 "address", expr, type);
5747 error ("%qE is not a valid template argument for type %qT "
5748 "because it is not an object with external linkage",
5753 if (!DECL_EXTERNAL_LINKAGE_P (expr))
5755 error ("%qE is not a valid template argument for type %qT "
5756 "because object %qD has not external linkage",
5761 expr = build_nop (type, build_address (expr));
5763 /* [temp.arg.nontype]/5, bullet 4
5765 For a non-type template-parameter of type pointer to function, only
5766 the function-to-pointer conversion (_conv.func_) is applied. If the
5767 template-argument represents a set of overloaded functions (or a
5768 pointer to such), the matching function is selected from the set
5770 else if (TYPE_PTRFN_P (type))
5772 /* If the argument is a template-id, we might not have enough
5773 context information to decay the pointer. */
5774 if (!type_unknown_p (expr_type))
5776 expr = decay_conversion (expr, complain);
5777 if (expr == error_mark_node)
5778 return error_mark_node;
5781 if (cxx_dialect >= cxx0x && integer_zerop (expr))
5782 /* Null pointer values are OK in C++11. */
5783 return perform_qualification_conversions (type, expr);
5785 expr = convert_nontype_argument_function (type, expr);
5786 if (!expr || expr == error_mark_node)
5789 /* [temp.arg.nontype]/5, bullet 5
5791 For a non-type template-parameter of type reference to function, no
5792 conversions apply. If the template-argument represents a set of
5793 overloaded functions, the matching function is selected from the set
5795 else if (TYPE_REFFN_P (type))
5797 if (TREE_CODE (expr) == ADDR_EXPR)
5799 error ("%qE is not a valid template argument for type %qT "
5800 "because it is a pointer", expr, type);
5801 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
5805 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
5806 if (!expr || expr == error_mark_node)
5809 expr = build_nop (type, build_address (expr));
5811 /* [temp.arg.nontype]/5, bullet 6
5813 For a non-type template-parameter of type pointer to member function,
5814 no conversions apply. If the template-argument represents a set of
5815 overloaded member functions, the matching member function is selected
5816 from the set (_over.over_). */
5817 else if (TYPE_PTRMEMFUNC_P (type))
5819 expr = instantiate_type (type, expr, tf_none);
5820 if (expr == error_mark_node)
5821 return error_mark_node;
5823 /* [temp.arg.nontype] bullet 1 says the pointer to member
5824 expression must be a pointer-to-member constant. */
5825 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5826 return error_mark_node;
5828 /* There is no way to disable standard conversions in
5829 resolve_address_of_overloaded_function (called by
5830 instantiate_type). It is possible that the call succeeded by
5831 converting &B::I to &D::I (where B is a base of D), so we need
5832 to reject this conversion here.
5834 Actually, even if there was a way to disable standard conversions,
5835 it would still be better to reject them here so that we can
5836 provide a superior diagnostic. */
5837 if (!same_type_p (TREE_TYPE (expr), type))
5839 error ("%qE is not a valid template argument for type %qT "
5840 "because it is of type %qT", expr, type,
5842 /* If we are just one standard conversion off, explain. */
5843 if (can_convert (type, TREE_TYPE (expr), complain))
5844 inform (input_location,
5845 "standard conversions are not allowed in this context");
5849 /* [temp.arg.nontype]/5, bullet 7
5851 For a non-type template-parameter of type pointer to data member,
5852 qualification conversions (_conv.qual_) are applied. */
5853 else if (TYPE_PTRDATAMEM_P (type))
5855 /* [temp.arg.nontype] bullet 1 says the pointer to member
5856 expression must be a pointer-to-member constant. */
5857 if (!check_valid_ptrmem_cst_expr (type, expr, complain))
5858 return error_mark_node;
5860 expr = perform_qualification_conversions (type, expr);
5861 if (expr == error_mark_node)
5864 else if (NULLPTR_TYPE_P (type))
5866 if (expr != nullptr_node)
5868 error ("%qE is not a valid template argument for type %qT "
5869 "because it is of type %qT", expr, type, TREE_TYPE (expr));
5874 /* A template non-type parameter must be one of the above. */
5878 /* Sanity check: did we actually convert the argument to the
5880 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5881 (type, TREE_TYPE (expr)));
5885 /* Subroutine of coerce_template_template_parms, which returns 1 if
5886 PARM_PARM and ARG_PARM match using the rule for the template
5887 parameters of template template parameters. Both PARM and ARG are
5888 template parameters; the rest of the arguments are the same as for
5889 coerce_template_template_parms.
5892 coerce_template_template_parm (tree parm,
5894 tsubst_flags_t complain,
5898 if (arg == NULL_TREE || arg == error_mark_node
5899 || parm == NULL_TREE || parm == error_mark_node)
5902 if (TREE_CODE (arg) != TREE_CODE (parm))
5905 switch (TREE_CODE (parm))
5908 /* We encounter instantiations of templates like
5909 template <template <template <class> class> class TT>
5912 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5913 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5915 if (!coerce_template_template_parms
5916 (parmparm, argparm, complain, in_decl, outer_args))
5922 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
5923 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5924 /* Argument is a parameter pack but parameter is not. */
5929 /* The tsubst call is used to handle cases such as
5931 template <int> class C {};
5932 template <class T, template <T> class TT> class D {};
5935 i.e. the parameter list of TT depends on earlier parameters. */
5936 if (!uses_template_parms (TREE_TYPE (arg))
5938 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
5942 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
5943 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5944 /* Argument is a parameter pack but parameter is not. */
5957 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
5958 template template parameters. Both PARM_PARMS and ARG_PARMS are
5959 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
5962 Consider the example:
5963 template <class T> class A;
5964 template<template <class U> class TT> class B;
5966 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
5967 the parameters to A, and OUTER_ARGS contains A. */
5970 coerce_template_template_parms (tree parm_parms,
5972 tsubst_flags_t complain,
5976 int nparms, nargs, i;
5980 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
5981 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
5983 nparms = TREE_VEC_LENGTH (parm_parms);
5984 nargs = TREE_VEC_LENGTH (arg_parms);
5986 /* Determine whether we have a parameter pack at the end of the
5987 template template parameter's template parameter list. */
5988 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
5990 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
5992 if (parm == error_mark_node)
5995 switch (TREE_CODE (parm))
5999 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
6004 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
6014 && !(variadic_p && nargs >= nparms - 1))
6017 /* Check all of the template parameters except the parameter pack at
6018 the end (if any). */
6019 for (i = 0; i < nparms - variadic_p; ++i)
6021 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
6022 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6025 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6026 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6028 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6036 /* Check each of the template parameters in the template
6037 argument against the template parameter pack at the end of
6038 the template template parameter. */
6039 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
6042 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
6044 for (; i < nargs; ++i)
6046 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
6049 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
6051 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
6060 /* Verifies that the deduced template arguments (in TARGS) for the
6061 template template parameters (in TPARMS) represent valid bindings,
6062 by comparing the template parameter list of each template argument
6063 to the template parameter list of its corresponding template
6064 template parameter, in accordance with DR150. This
6065 routine can only be called after all template arguments have been
6066 deduced. It will return TRUE if all of the template template
6067 parameter bindings are okay, FALSE otherwise. */
6069 template_template_parm_bindings_ok_p (tree tparms, tree targs)
6071 int i, ntparms = TREE_VEC_LENGTH (tparms);
6074 /* We're dealing with template parms in this process. */
6075 ++processing_template_decl;
6077 targs = INNERMOST_TEMPLATE_ARGS (targs);
6079 for (i = 0; i < ntparms; ++i)
6081 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
6082 tree targ = TREE_VEC_ELT (targs, i);
6084 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
6086 tree packed_args = NULL_TREE;
6089 if (ARGUMENT_PACK_P (targ))
6091 /* Look inside the argument pack. */
6092 packed_args = ARGUMENT_PACK_ARGS (targ);
6093 len = TREE_VEC_LENGTH (packed_args);
6096 for (idx = 0; idx < len; ++idx)
6098 tree targ_parms = NULL_TREE;
6101 /* Extract the next argument from the argument
6103 targ = TREE_VEC_ELT (packed_args, idx);
6105 if (PACK_EXPANSION_P (targ))
6106 /* Look at the pattern of the pack expansion. */
6107 targ = PACK_EXPANSION_PATTERN (targ);
6109 /* Extract the template parameters from the template
6111 if (TREE_CODE (targ) == TEMPLATE_DECL)
6112 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
6113 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
6114 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
6116 /* Verify that we can coerce the template template
6117 parameters from the template argument to the template
6118 parameter. This requires an exact match. */
6120 && !coerce_template_template_parms
6121 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
6136 --processing_template_decl;
6140 /* Since type attributes aren't mangled, we need to strip them from
6141 template type arguments. */
6144 canonicalize_type_argument (tree arg, tsubst_flags_t complain)
6147 if (!arg || arg == error_mark_node || arg == TYPE_CANONICAL (arg))
6149 mv = TYPE_MAIN_VARIANT (arg);
6150 arg = strip_typedefs (arg);
6151 if (TYPE_ALIGN (arg) != TYPE_ALIGN (mv)
6152 || TYPE_ATTRIBUTES (arg) != TYPE_ATTRIBUTES (mv))
6154 if (complain & tf_warning)
6155 warning (0, "ignoring attributes on template argument %qT", arg);
6156 arg = build_aligned_type (arg, TYPE_ALIGN (mv));
6157 arg = cp_build_type_attribute_variant (arg, TYPE_ATTRIBUTES (mv));
6162 /* Convert the indicated template ARG as necessary to match the
6163 indicated template PARM. Returns the converted ARG, or
6164 error_mark_node if the conversion was unsuccessful. Error and
6165 warning messages are issued under control of COMPLAIN. This
6166 conversion is for the Ith parameter in the parameter list. ARGS is
6167 the full set of template arguments deduced so far. */
6170 convert_template_argument (tree parm,
6173 tsubst_flags_t complain,
6179 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
6181 if (TREE_CODE (arg) == TREE_LIST
6182 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
6184 /* The template argument was the name of some
6185 member function. That's usually
6186 invalid, but static members are OK. In any
6187 case, grab the underlying fields/functions
6188 and issue an error later if required. */
6189 orig_arg = TREE_VALUE (arg);
6190 TREE_TYPE (arg) = unknown_type_node;
6195 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
6196 requires_type = (TREE_CODE (parm) == TYPE_DECL
6197 || requires_tmpl_type);
6199 /* When determining whether an argument pack expansion is a template,
6200 look at the pattern. */
6201 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
6202 arg = PACK_EXPANSION_PATTERN (arg);
6204 /* Deal with an injected-class-name used as a template template arg. */
6205 if (requires_tmpl_type && CLASS_TYPE_P (arg))
6207 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg));
6208 if (TREE_CODE (t) == TEMPLATE_DECL)
6210 if (cxx_dialect >= cxx0x)
6211 /* OK under DR 1004. */;
6212 else if (complain & tf_warning_or_error)
6213 pedwarn (input_location, OPT_Wpedantic, "injected-class-name %qD"
6214 " used as template template argument", TYPE_NAME (arg));
6215 else if (flag_pedantic_errors)
6223 ((TREE_CODE (arg) == TEMPLATE_DECL
6224 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
6225 || (requires_tmpl_type && TREE_CODE (arg) == TYPE_ARGUMENT_PACK)
6226 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6227 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
6230 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
6231 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
6232 arg = TYPE_STUB_DECL (arg);
6234 is_type = TYPE_P (arg) || is_tmpl_type;
6236 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
6237 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
6239 if (TREE_CODE (TREE_OPERAND (arg, 1)) == BIT_NOT_EXPR)
6241 if (complain & tf_error)
6242 error ("invalid use of destructor %qE as a type", orig_arg);
6243 return error_mark_node;
6246 permerror (input_location,
6247 "to refer to a type member of a template parameter, "
6248 "use %<typename %E%>", orig_arg);
6250 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
6251 TREE_OPERAND (arg, 1),
6257 if (is_type != requires_type)
6261 if (complain & tf_error)
6263 error ("type/value mismatch at argument %d in template "
6264 "parameter list for %qD",
6267 error (" expected a constant of type %qT, got %qT",
6269 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
6270 else if (requires_tmpl_type)
6271 error (" expected a class template, got %qE", orig_arg);
6273 error (" expected a type, got %qE", orig_arg);
6276 return error_mark_node;
6278 if (is_tmpl_type ^ requires_tmpl_type)
6280 if (in_decl && (complain & tf_error))
6282 error ("type/value mismatch at argument %d in template "
6283 "parameter list for %qD",
6286 error (" expected a type, got %qT", DECL_NAME (arg));
6288 error (" expected a class template, got %qT", orig_arg);
6290 return error_mark_node;
6295 if (requires_tmpl_type)
6297 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6299 else if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
6300 /* The number of argument required is not known yet.
6301 Just accept it for now. */
6302 val = TREE_TYPE (arg);
6305 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
6308 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
6310 if (coerce_template_template_parms (parmparm, argparm,
6316 /* TEMPLATE_TEMPLATE_PARM node is preferred over
6318 if (val != error_mark_node)
6320 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
6321 val = TREE_TYPE (val);
6322 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION)
6323 val = make_pack_expansion (val);
6328 if (in_decl && (complain & tf_error))
6330 error ("type/value mismatch at argument %d in "
6331 "template parameter list for %qD",
6333 error (" expected a template of type %qD, got %qT",
6337 val = error_mark_node;
6343 /* We only form one instance of each template specialization.
6344 Therefore, if we use a non-canonical variant (i.e., a
6345 typedef), any future messages referring to the type will use
6346 the typedef, which is confusing if those future uses do not
6347 themselves also use the typedef. */
6349 val = canonicalize_type_argument (val, complain);
6353 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
6355 if (invalid_nontype_parm_type_p (t, complain))
6356 return error_mark_node;
6358 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
6360 if (same_type_p (t, TREE_TYPE (orig_arg)))
6364 /* Not sure if this is reachable, but it doesn't hurt
6366 error ("type mismatch in nontype parameter pack");
6367 val = error_mark_node;
6370 else if (!dependent_template_arg_p (orig_arg)
6371 && !uses_template_parms (t))
6372 /* We used to call digest_init here. However, digest_init
6373 will report errors, which we don't want when complain
6374 is zero. More importantly, digest_init will try too
6375 hard to convert things: for example, `0' should not be
6376 converted to pointer type at this point according to
6377 the standard. Accepting this is not merely an
6378 extension, since deciding whether or not these
6379 conversions can occur is part of determining which
6380 function template to call, or whether a given explicit
6381 argument specification is valid. */
6382 val = convert_nontype_argument (t, orig_arg, complain);
6384 val = strip_typedefs_expr (orig_arg);
6386 if (val == NULL_TREE)
6387 val = error_mark_node;
6388 else if (val == error_mark_node && (complain & tf_error))
6389 error ("could not convert template argument %qE to %qT", orig_arg, t);
6391 if (TREE_CODE (val) == SCOPE_REF)
6393 /* Strip typedefs from the SCOPE_REF. */
6394 tree type = canonicalize_type_argument (TREE_TYPE (val), complain);
6395 tree scope = canonicalize_type_argument (TREE_OPERAND (val, 0),
6397 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1),
6398 QUALIFIED_NAME_IS_TEMPLATE (val));
6405 /* Coerces the remaining template arguments in INNER_ARGS (from
6406 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
6407 Returns the coerced argument pack. PARM_IDX is the position of this
6408 parameter in the template parameter list. ARGS is the original
6409 template argument list. */
6411 coerce_template_parameter_pack (tree parms,
6419 tsubst_flags_t complain)
6421 tree parm = TREE_VEC_ELT (parms, parm_idx);
6422 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6425 tree packed_types = NULL_TREE;
6427 if (arg_idx > nargs)
6430 packed_args = make_tree_vec (nargs - arg_idx);
6432 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
6433 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
6435 /* When the template parameter is a non-type template
6436 parameter pack whose type uses parameter packs, we need
6437 to look at each of the template arguments
6438 separately. Build a vector of the types for these
6439 non-type template parameters in PACKED_TYPES. */
6441 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
6442 packed_types = tsubst_pack_expansion (expansion, args,
6445 if (packed_types == error_mark_node)
6446 return error_mark_node;
6448 /* Check that we have the right number of arguments. */
6450 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
6451 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
6454 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
6455 error ("wrong number of template arguments (%d, should be %d)",
6456 nargs, needed_parms);
6457 return error_mark_node;
6460 /* If we aren't able to check the actual arguments now
6461 (because they haven't been expanded yet), we can at least
6462 verify that all of the types used for the non-type
6463 template parameter pack are, in fact, valid for non-type
6464 template parameters. */
6466 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
6468 int j, len = TREE_VEC_LENGTH (packed_types);
6469 for (j = 0; j < len; ++j)
6471 tree t = TREE_VEC_ELT (packed_types, j);
6472 if (invalid_nontype_parm_type_p (t, complain))
6473 return error_mark_node;
6478 /* Convert the remaining arguments, which will be a part of the
6479 parameter pack "parm". */
6480 for (; arg_idx < nargs; ++arg_idx)
6482 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
6483 tree actual_parm = TREE_VALUE (parm);
6485 if (packed_types && !PACK_EXPANSION_P (arg))
6487 /* When we have a vector of types (corresponding to the
6488 non-type template parameter pack that uses parameter
6489 packs in its type, as mention above), and the
6490 argument is not an expansion (which expands to a
6491 currently unknown number of arguments), clone the
6492 parm and give it the next type in PACKED_TYPES. */
6493 actual_parm = copy_node (actual_parm);
6494 TREE_TYPE (actual_parm) =
6495 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
6498 if (arg == error_mark_node)
6500 if (complain & tf_error)
6501 error ("template argument %d is invalid", arg_idx + 1);
6504 arg = convert_template_argument (actual_parm,
6505 arg, new_args, complain, parm_idx,
6507 if (arg == error_mark_node)
6509 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
6512 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
6513 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
6514 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK);
6517 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
6518 TREE_TYPE (argument_pack)
6519 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
6520 TREE_CONSTANT (argument_pack) = 1;
6523 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
6524 #ifdef ENABLE_CHECKING
6525 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args,
6526 TREE_VEC_LENGTH (packed_args));
6528 return argument_pack;
6531 /* Returns true if the template argument vector ARGS contains
6532 any pack expansions, false otherwise. */
6535 any_pack_expanson_args_p (tree args)
6539 for (i = 0; i < TREE_VEC_LENGTH (args); ++i)
6540 if (PACK_EXPANSION_P (TREE_VEC_ELT (args, i)))
6545 /* Convert all template arguments to their appropriate types, and
6546 return a vector containing the innermost resulting template
6547 arguments. If any error occurs, return error_mark_node. Error and
6548 warning messages are issued under control of COMPLAIN.
6550 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
6551 for arguments not specified in ARGS. Otherwise, if
6552 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
6553 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
6554 USE_DEFAULT_ARGS is false, then all arguments must be specified in
6558 coerce_template_parms (tree parms,
6561 tsubst_flags_t complain,
6562 bool require_all_args,
6563 bool use_default_args)
6565 int nparms, nargs, parm_idx, arg_idx, lost = 0;
6568 tree new_inner_args;
6569 int saved_unevaluated_operand;
6570 int saved_inhibit_evaluation_warnings;
6572 /* When used as a boolean value, indicates whether this is a
6573 variadic template parameter list. Since it's an int, we can also
6574 subtract it from nparms to get the number of non-variadic
6577 int post_variadic_parms = 0;
6579 if (args == error_mark_node)
6580 return error_mark_node;
6582 nparms = TREE_VEC_LENGTH (parms);
6584 /* Determine if there are any parameter packs. */
6585 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
6587 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
6589 ++post_variadic_parms;
6590 if (template_parameter_pack_p (tparm))
6594 inner_args = INNERMOST_TEMPLATE_ARGS (args);
6595 /* If there are no parameters that follow a parameter pack, we need to
6596 expand any argument packs so that we can deduce a parameter pack from
6597 some non-packed args followed by an argument pack, as in variadic85.C.
6598 If there are such parameters, we need to leave argument packs intact
6599 so the arguments are assigned properly. This can happen when dealing
6600 with a nested class inside a partial specialization of a class
6601 template, as in variadic92.C, or when deducing a template parameter pack
6602 from a sub-declarator, as in variadic114.C. */
6603 if (!post_variadic_parms)
6604 inner_args = expand_template_argument_pack (inner_args);
6606 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
6607 if ((nargs > nparms && !variadic_p)
6608 || (nargs < nparms - variadic_p
6610 && !any_pack_expanson_args_p (inner_args)
6611 && (!use_default_args
6612 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
6613 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
6615 if (complain & tf_error)
6619 nparms -= variadic_p;
6620 error ("wrong number of template arguments "
6621 "(%d, should be %d or more)", nargs, nparms);
6624 error ("wrong number of template arguments "
6625 "(%d, should be %d)", nargs, nparms);
6628 error ("provided for %q+D", in_decl);
6631 return error_mark_node;
6634 /* We need to evaluate the template arguments, even though this
6635 template-id may be nested within a "sizeof". */
6636 saved_unevaluated_operand = cp_unevaluated_operand;
6637 cp_unevaluated_operand = 0;
6638 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
6639 c_inhibit_evaluation_warnings = 0;
6640 new_inner_args = make_tree_vec (nparms);
6641 new_args = add_outermost_template_args (args, new_inner_args);
6642 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
6647 /* Get the Ith template parameter. */
6648 parm = TREE_VEC_ELT (parms, parm_idx);
6650 if (parm == error_mark_node)
6652 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
6656 /* Calculate the next argument. */
6657 if (arg_idx < nargs)
6658 arg = TREE_VEC_ELT (inner_args, arg_idx);
6662 if (template_parameter_pack_p (TREE_VALUE (parm))
6663 && !(arg && ARGUMENT_PACK_P (arg)))
6665 /* All remaining arguments will be placed in the
6666 template parameter pack PARM. */
6667 arg = coerce_template_parameter_pack (parms, parm_idx, args,
6668 inner_args, arg_idx,
6672 /* Store this argument. */
6673 if (arg == error_mark_node)
6675 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
6677 /* We are done with all of the arguments. */
6684 if (PACK_EXPANSION_P (arg))
6686 /* We don't know how many args we have yet, just
6687 use the unconverted ones for now. */
6688 new_inner_args = inner_args;
6692 else if (require_all_args)
6694 /* There must be a default arg in this case. */
6695 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
6697 /* The position of the first default template argument,
6698 is also the number of non-defaulted arguments in NEW_INNER_ARGS.
6700 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6701 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx);
6706 if (arg == error_mark_node)
6708 if (complain & tf_error)
6709 error ("template argument %d is invalid", arg_idx + 1);
6712 /* This only occurs if there was an error in the template
6713 parameter list itself (which we would already have
6714 reported) that we are trying to recover from, e.g., a class
6715 template with a parameter list such as
6716 template<typename..., typename>. */
6719 arg = convert_template_argument (TREE_VALUE (parm),
6720 arg, new_args, complain,
6723 if (arg == error_mark_node)
6725 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
6727 cp_unevaluated_operand = saved_unevaluated_operand;
6728 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
6731 return error_mark_node;
6733 #ifdef ENABLE_CHECKING
6734 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args))
6735 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args,
6736 TREE_VEC_LENGTH (new_inner_args));
6739 return new_inner_args;
6742 /* Like coerce_template_parms. If PARMS represents all template
6743 parameters levels, this function returns a vector of vectors
6744 representing all the resulting argument levels. Note that in this
6745 case, only the innermost arguments are coerced because the
6746 outermost ones are supposed to have been coerced already.
6748 Otherwise, if PARMS represents only (the innermost) vector of
6749 parameters, this function returns a vector containing just the
6750 innermost resulting arguments. */
6753 coerce_innermost_template_parms (tree parms,
6756 tsubst_flags_t complain,
6757 bool require_all_args,
6758 bool use_default_args)
6760 int parms_depth = TMPL_PARMS_DEPTH (parms);
6761 int args_depth = TMPL_ARGS_DEPTH (args);
6764 if (parms_depth > 1)
6766 coerced_args = make_tree_vec (parms_depth);
6770 for (level = parms, cur_depth = parms_depth;
6771 parms_depth > 0 && level != NULL_TREE;
6772 level = TREE_CHAIN (level), --cur_depth)
6775 if (cur_depth == args_depth)
6776 l = coerce_template_parms (TREE_VALUE (level),
6777 args, in_decl, complain,
6781 l = TMPL_ARGS_LEVEL (args, cur_depth);
6783 if (l == error_mark_node)
6784 return error_mark_node;
6786 SET_TMPL_ARGS_LEVEL (coerced_args, cur_depth, l);
6790 coerced_args = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parms),
6791 args, in_decl, complain,
6794 return coerced_args;
6797 /* Returns 1 if template args OT and NT are equivalent. */
6800 template_args_equal (tree ot, tree nt)
6804 if (nt == NULL_TREE || ot == NULL_TREE)
6807 if (TREE_CODE (nt) == TREE_VEC)
6808 /* For member templates */
6809 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
6810 else if (PACK_EXPANSION_P (ot))
6811 return (PACK_EXPANSION_P (nt)
6812 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
6813 PACK_EXPANSION_PATTERN (nt))
6814 && template_args_equal (PACK_EXPANSION_EXTRA_ARGS (ot),
6815 PACK_EXPANSION_EXTRA_ARGS (nt)));
6816 else if (ARGUMENT_PACK_P (ot))
6821 if (!ARGUMENT_PACK_P (nt))
6824 opack = ARGUMENT_PACK_ARGS (ot);
6825 npack = ARGUMENT_PACK_ARGS (nt);
6826 len = TREE_VEC_LENGTH (opack);
6827 if (TREE_VEC_LENGTH (npack) != len)
6829 for (i = 0; i < len; ++i)
6830 if (!template_args_equal (TREE_VEC_ELT (opack, i),
6831 TREE_VEC_ELT (npack, i)))
6835 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT)
6837 /* We get here probably because we are in the middle of substituting
6838 into the pattern of a pack expansion. In that case the
6839 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are
6840 interested in. So we want to use the initial pack argument for
6842 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot);
6843 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT)
6844 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt);
6845 return template_args_equal (ot, nt);
6847 else if (TYPE_P (nt))
6848 return TYPE_P (ot) && same_type_p (ot, nt);
6849 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
6852 return cp_tree_equal (ot, nt);
6855 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets of
6856 template arguments. Returns 0 otherwise, and updates OLDARG_PTR and
6857 NEWARG_PTR with the offending arguments if they are non-NULL. */
6860 comp_template_args_with_info (tree oldargs, tree newargs,
6861 tree *oldarg_ptr, tree *newarg_ptr)
6865 if (oldargs == newargs)
6868 if (!oldargs || !newargs)
6871 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
6874 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
6876 tree nt = TREE_VEC_ELT (newargs, i);
6877 tree ot = TREE_VEC_ELT (oldargs, i);
6879 if (! template_args_equal (ot, nt))
6881 if (oldarg_ptr != NULL)
6883 if (newarg_ptr != NULL)
6891 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
6892 of template arguments. Returns 0 otherwise. */
6895 comp_template_args (tree oldargs, tree newargs)
6897 return comp_template_args_with_info (oldargs, newargs, NULL, NULL);
6901 add_pending_template (tree d)
6903 tree ti = (TYPE_P (d)
6904 ? CLASSTYPE_TEMPLATE_INFO (d)
6905 : DECL_TEMPLATE_INFO (d));
6906 struct pending_template *pt;
6909 if (TI_PENDING_TEMPLATE_FLAG (ti))
6912 /* We are called both from instantiate_decl, where we've already had a
6913 tinst_level pushed, and instantiate_template, where we haven't.
6915 level = !current_tinst_level || current_tinst_level->decl != d;
6918 push_tinst_level (d);
6920 pt = ggc_alloc_pending_template ();
6922 pt->tinst = current_tinst_level;
6923 if (last_pending_template)
6924 last_pending_template->next = pt;
6926 pending_templates = pt;
6928 last_pending_template = pt;
6930 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
6937 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
6938 ARGLIST. Valid choices for FNS are given in the cp-tree.def
6939 documentation for TEMPLATE_ID_EXPR. */
6942 lookup_template_function (tree fns, tree arglist)
6946 if (fns == error_mark_node || arglist == error_mark_node)
6947 return error_mark_node;
6949 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
6951 if (!is_overloaded_fn (fns) && TREE_CODE (fns) != IDENTIFIER_NODE)
6953 error ("%q#D is not a function template", fns);
6954 return error_mark_node;
6957 if (BASELINK_P (fns))
6959 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
6961 BASELINK_FUNCTIONS (fns),
6966 type = TREE_TYPE (fns);
6967 if (TREE_CODE (fns) == OVERLOAD || !type)
6968 type = unknown_type_node;
6970 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
6973 /* Within the scope of a template class S<T>, the name S gets bound
6974 (in build_self_reference) to a TYPE_DECL for the class, not a
6975 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
6976 or one of its enclosing classes, and that type is a template,
6977 return the associated TEMPLATE_DECL. Otherwise, the original
6980 Also handle the case when DECL is a TREE_LIST of ambiguous
6981 injected-class-names from different bases. */
6984 maybe_get_template_decl_from_type_decl (tree decl)
6986 if (decl == NULL_TREE)
6989 /* DR 176: A lookup that finds an injected-class-name (10.2
6990 [class.member.lookup]) can result in an ambiguity in certain cases
6991 (for example, if it is found in more than one base class). If all of
6992 the injected-class-names that are found refer to specializations of
6993 the same class template, and if the name is followed by a
6994 template-argument-list, the reference refers to the class template
6995 itself and not a specialization thereof, and is not ambiguous. */
6996 if (TREE_CODE (decl) == TREE_LIST)
6998 tree t, tmpl = NULL_TREE;
6999 for (t = decl; t; t = TREE_CHAIN (t))
7001 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t));
7004 else if (tmpl != elt)
7007 if (tmpl && t == NULL_TREE)
7013 return (decl != NULL_TREE
7014 && DECL_SELF_REFERENCE_P (decl)
7015 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
7016 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
7019 /* Given an IDENTIFIER_NODE (or type TEMPLATE_DECL) and a chain of
7020 parameters, find the desired type.
7022 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
7024 IN_DECL, if non-NULL, is the template declaration we are trying to
7027 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
7028 the class we are looking up.
7030 Issue error and warning messages under control of COMPLAIN.
7032 If the template class is really a local class in a template
7033 function, then the FUNCTION_CONTEXT is the function in which it is
7036 ??? Note that this function is currently called *twice* for each
7037 template-id: the first time from the parser, while creating the
7038 incomplete type (finish_template_type), and the second type during the
7039 real instantiation (instantiate_template_class). This is surely something
7040 that we want to avoid. It also causes some problems with argument
7041 coercion (see convert_nontype_argument for more information on this). */
7044 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context,
7045 int entering_scope, tsubst_flags_t complain)
7047 tree templ = NULL_TREE, parmlist;
7054 if (TREE_CODE (d1) == IDENTIFIER_NODE)
7056 tree value = innermost_non_namespace_value (d1);
7057 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
7062 push_decl_namespace (context);
7063 templ = lookup_name (d1);
7064 templ = maybe_get_template_decl_from_type_decl (templ);
7066 pop_decl_namespace ();
7069 context = DECL_CONTEXT (templ);
7071 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
7073 tree type = TREE_TYPE (d1);
7075 /* If we are declaring a constructor, say A<T>::A<T>, we will get
7076 an implicit typename for the second A. Deal with it. */
7077 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
7078 type = TREE_TYPE (type);
7080 if (CLASSTYPE_TEMPLATE_INFO (type))
7082 templ = CLASSTYPE_TI_TEMPLATE (type);
7083 d1 = DECL_NAME (templ);
7086 else if (TREE_CODE (d1) == ENUMERAL_TYPE
7087 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
7089 templ = TYPE_TI_TEMPLATE (d1);
7090 d1 = DECL_NAME (templ);
7092 else if (TREE_CODE (d1) == TEMPLATE_DECL
7093 && DECL_TEMPLATE_RESULT (d1)
7094 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
7097 d1 = DECL_NAME (templ);
7098 context = DECL_CONTEXT (templ);
7100 else if (DECL_TEMPLATE_TEMPLATE_PARM_P (d1))
7103 d1 = DECL_NAME (templ);
7106 /* Issue an error message if we didn't find a template. */
7109 if (complain & tf_error)
7110 error ("%qT is not a template", d1);
7111 return error_mark_node;
7114 if (TREE_CODE (templ) != TEMPLATE_DECL
7115 /* Make sure it's a user visible template, if it was named by
7117 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
7118 && !PRIMARY_TEMPLATE_P (templ)))
7120 if (complain & tf_error)
7122 error ("non-template type %qT used as a template", d1);
7124 error ("for template declaration %q+D", in_decl);
7126 return error_mark_node;
7129 complain &= ~tf_user;
7131 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
7133 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
7134 template arguments */
7140 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
7142 /* Consider an example where a template template parameter declared as
7144 template <class T, class U = std::allocator<T> > class TT
7146 The template parameter level of T and U are one level larger than
7147 of TT. To proper process the default argument of U, say when an
7148 instantiation `TT<int>' is seen, we need to build the full
7149 arguments containing {int} as the innermost level. Outer levels,
7150 available when not appearing as default template argument, can be
7151 obtained from the arguments of the enclosing template.
7153 Suppose that TT is later substituted with std::vector. The above
7154 instantiation is `TT<int, std::allocator<T> >' with TT at
7155 level 1, and T at level 2, while the template arguments at level 1
7156 becomes {std::vector} and the inner level 2 is {int}. */
7158 outer = DECL_CONTEXT (templ);
7160 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
7161 else if (current_template_parms)
7162 /* This is an argument of the current template, so we haven't set
7163 DECL_CONTEXT yet. */
7164 outer = current_template_args ();
7167 arglist = add_to_template_args (outer, arglist);
7169 arglist2 = coerce_template_parms (parmlist, arglist, templ,
7171 /*require_all_args=*/true,
7172 /*use_default_args=*/true);
7173 if (arglist2 == error_mark_node
7174 || (!uses_template_parms (arglist2)
7175 && check_instantiated_args (templ, arglist2, complain)))
7176 return error_mark_node;
7178 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
7183 tree template_type = TREE_TYPE (templ);
7186 tree found = NULL_TREE;
7189 int is_dependent_type;
7190 int use_partial_inst_tmpl = false;
7192 if (template_type == error_mark_node)
7193 /* An error occured while building the template TEMPL, and a
7194 diagnostic has most certainly been emitted for that
7195 already. Let's propagate that error. */
7196 return error_mark_node;
7198 gen_tmpl = most_general_template (templ);
7199 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
7200 parm_depth = TMPL_PARMS_DEPTH (parmlist);
7201 arg_depth = TMPL_ARGS_DEPTH (arglist);
7203 if (arg_depth == 1 && parm_depth > 1)
7205 /* We've been given an incomplete set of template arguments.
7208 template <class T> struct S1 {
7209 template <class U> struct S2 {};
7210 template <class U> struct S2<U*> {};
7213 we will be called with an ARGLIST of `U*', but the
7214 TEMPLATE will be `template <class T> template
7215 <class U> struct S1<T>::S2'. We must fill in the missing
7218 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
7220 arg_depth = TMPL_ARGS_DEPTH (arglist);
7223 /* Now we should have enough arguments. */
7224 gcc_assert (parm_depth == arg_depth);
7226 /* From here on, we're only interested in the most general
7229 /* Calculate the BOUND_ARGS. These will be the args that are
7230 actually tsubst'd into the definition to create the
7234 /* We have multiple levels of arguments to coerce, at once. */
7236 int saved_depth = TMPL_ARGS_DEPTH (arglist);
7238 tree bound_args = make_tree_vec (parm_depth);
7240 for (i = saved_depth,
7241 t = DECL_TEMPLATE_PARMS (gen_tmpl);
7242 i > 0 && t != NULL_TREE;
7243 --i, t = TREE_CHAIN (t))
7246 if (i == saved_depth)
7247 a = coerce_template_parms (TREE_VALUE (t),
7250 /*require_all_args=*/true,
7251 /*use_default_args=*/true);
7253 /* Outer levels should have already been coerced. */
7254 a = TMPL_ARGS_LEVEL (arglist, i);
7256 /* Don't process further if one of the levels fails. */
7257 if (a == error_mark_node)
7259 /* Restore the ARGLIST to its full size. */
7260 TREE_VEC_LENGTH (arglist) = saved_depth;
7261 return error_mark_node;
7264 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
7266 /* We temporarily reduce the length of the ARGLIST so
7267 that coerce_template_parms will see only the arguments
7268 corresponding to the template parameters it is
7270 TREE_VEC_LENGTH (arglist)--;
7273 /* Restore the ARGLIST to its full size. */
7274 TREE_VEC_LENGTH (arglist) = saved_depth;
7276 arglist = bound_args;
7280 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
7281 INNERMOST_TEMPLATE_ARGS (arglist),
7284 /*require_all_args=*/true,
7285 /*use_default_args=*/true);
7287 if (arglist == error_mark_node)
7288 /* We were unable to bind the arguments. */
7289 return error_mark_node;
7291 /* In the scope of a template class, explicit references to the
7292 template class refer to the type of the template, not any
7293 instantiation of it. For example, in:
7295 template <class T> class C { void f(C<T>); }
7297 the `C<T>' is just the same as `C'. Outside of the
7298 class, however, such a reference is an instantiation. */
7300 || !PRIMARY_TEMPLATE_P (gen_tmpl)
7301 || currently_open_class (template_type))
7302 /* comp_template_args is expensive, check it last. */
7303 && comp_template_args (TYPE_TI_ARGS (template_type),
7305 return template_type;
7307 /* If we already have this specialization, return it. */
7308 elt.tmpl = gen_tmpl;
7310 hash = hash_specialization (&elt);
7311 entry = (spec_entry *) htab_find_with_hash (type_specializations,
7317 is_dependent_type = uses_template_parms (arglist);
7319 /* If the deduced arguments are invalid, then the binding
7321 if (!is_dependent_type
7322 && check_instantiated_args (gen_tmpl,
7323 INNERMOST_TEMPLATE_ARGS (arglist),
7325 return error_mark_node;
7327 if (!is_dependent_type
7328 && !PRIMARY_TEMPLATE_P (gen_tmpl)
7329 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl))
7330 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
7332 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
7333 DECL_NAME (gen_tmpl),
7334 /*tag_scope=*/ts_global);
7338 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
7340 if (context == error_mark_node)
7341 return error_mark_node;
7344 context = global_namespace;
7346 /* Create the type. */
7347 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
7349 if (!is_dependent_type)
7351 set_current_access_from_decl (TYPE_NAME (template_type));
7352 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE,
7353 tsubst (ENUM_UNDERLYING_TYPE (template_type),
7354 arglist, complain, in_decl),
7355 SCOPED_ENUM_P (template_type), NULL);
7359 /* We don't want to call start_enum for this type, since
7360 the values for the enumeration constants may involve
7361 template parameters. And, no one should be interested
7362 in the enumeration constants for such a type. */
7363 t = cxx_make_type (ENUMERAL_TYPE);
7364 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
7366 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type));
7367 ENUM_FIXED_UNDERLYING_TYPE_P (t)
7368 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type);
7370 else if (DECL_ALIAS_TEMPLATE_P (gen_tmpl))
7372 /* The user referred to a specialization of an alias
7373 template represented by GEN_TMPL.
7375 [temp.alias]/2 says:
7377 When a template-id refers to the specialization of an
7378 alias template, it is equivalent to the associated
7379 type obtained by substitution of its
7380 template-arguments for the template-parameters in the
7381 type-id of the alias template. */
7383 t = tsubst (TREE_TYPE (gen_tmpl), arglist, complain, in_decl);
7384 /* Note that the call above (by indirectly calling
7385 register_specialization in tsubst_decl) registers the
7386 TYPE_DECL representing the specialization of the alias
7387 template. So next time someone substitutes ARGLIST for
7388 the template parms into the alias template (GEN_TMPL),
7389 she'll get that TYPE_DECL back. */
7391 if (t == error_mark_node)
7394 else if (CLASS_TYPE_P (template_type))
7396 t = make_class_type (TREE_CODE (template_type));
7397 CLASSTYPE_DECLARED_CLASS (t)
7398 = CLASSTYPE_DECLARED_CLASS (template_type);
7399 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
7400 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
7402 /* A local class. Make sure the decl gets registered properly. */
7403 if (context == current_function_decl)
7404 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
7406 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
7407 /* This instantiation is another name for the primary
7408 template type. Set the TYPE_CANONICAL field
7410 TYPE_CANONICAL (t) = template_type;
7411 else if (any_template_arguments_need_structural_equality_p (arglist))
7412 /* Some of the template arguments require structural
7413 equality testing, so this template class requires
7414 structural equality testing. */
7415 SET_TYPE_STRUCTURAL_EQUALITY (t);
7420 /* If we called start_enum or pushtag above, this information
7421 will already be set up. */
7424 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
7426 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
7427 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
7428 DECL_SOURCE_LOCATION (type_decl)
7429 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
7432 type_decl = TYPE_NAME (t);
7434 if (CLASS_TYPE_P (template_type))
7436 TREE_PRIVATE (type_decl)
7437 = TREE_PRIVATE (TYPE_MAIN_DECL (template_type));
7438 TREE_PROTECTED (type_decl)
7439 = TREE_PROTECTED (TYPE_MAIN_DECL (template_type));
7440 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
7442 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
7443 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
7447 /* Let's consider the explicit specialization of a member
7448 of a class template specialization that is implicitely instantiated,
7453 template<class U> struct M {}; //#0
7458 struct S<int>::M<char> //#1
7462 [temp.expl.spec]/4 says this is valid.
7464 In this case, when we write:
7467 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from
7470 When we encounter #1, we want to store the partial instantiation
7471 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE.
7473 For all cases other than this "explicit specialization of member of a
7474 class template", we just want to store the most general template into
7475 the CLASSTYPE_TI_TEMPLATE of M.
7477 This case of "explicit specialization of member of a class template"
7479 1/ the enclosing class is an instantiation of, and therefore not
7480 the same as, the context of the most general template, and
7481 2/ we aren't looking at the partial instantiation itself, i.e.
7482 the innermost arguments are not the same as the innermost parms of
7483 the most general template.
7485 So it's only when 1/ and 2/ happens that we want to use the partial
7486 instantiation of the member template in lieu of its most general
7489 if (PRIMARY_TEMPLATE_P (gen_tmpl)
7490 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist)
7491 /* the enclosing class must be an instantiation... */
7492 && CLASS_TYPE_P (context)
7493 && !same_type_p (context, DECL_CONTEXT (gen_tmpl)))
7495 tree partial_inst_args;
7496 TREE_VEC_LENGTH (arglist)--;
7497 ++processing_template_decl;
7499 tsubst (INNERMOST_TEMPLATE_ARGS
7500 (TYPE_TI_ARGS (TREE_TYPE (gen_tmpl))),
7501 arglist, complain, NULL_TREE);
7502 --processing_template_decl;
7503 TREE_VEC_LENGTH (arglist)++;
7504 use_partial_inst_tmpl =
7505 /*...and we must not be looking at the partial instantiation
7507 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist),
7511 if (!use_partial_inst_tmpl)
7512 /* This case is easy; there are no member templates involved. */
7516 /* This is a full instantiation of a member template. Find
7517 the partial instantiation of which this is an instance. */
7519 /* Temporarily reduce by one the number of levels in the ARGLIST
7520 so as to avoid comparing the last set of arguments. */
7521 TREE_VEC_LENGTH (arglist)--;
7522 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
7523 TREE_VEC_LENGTH (arglist)++;
7524 /* FOUND is either a proper class type, or an alias
7525 template specialization. In the later case, it's a
7526 TYPE_DECL, resulting from the substituting of arguments
7527 for parameters in the TYPE_DECL of the alias template
7528 done earlier. So be careful while getting the template
7530 found = TREE_CODE (found) == TYPE_DECL
7531 ? TYPE_TI_TEMPLATE (TREE_TYPE (found))
7532 : CLASSTYPE_TI_TEMPLATE (found);
7535 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist));
7538 slot = htab_find_slot_with_hash (type_specializations,
7539 &elt, hash, INSERT);
7540 entry = ggc_alloc_spec_entry ();
7544 /* Note this use of the partial instantiation so we can check it
7545 later in maybe_process_partial_specialization. */
7546 DECL_TEMPLATE_INSTANTIATIONS (templ)
7547 = tree_cons (arglist, t,
7548 DECL_TEMPLATE_INSTANTIATIONS (templ));
7550 if (TREE_CODE (template_type) == ENUMERAL_TYPE && !is_dependent_type)
7551 /* Now that the type has been registered on the instantiations
7552 list, we set up the enumerators. Because the enumeration
7553 constants may involve the enumeration type itself, we make
7554 sure to register the type first, and then create the
7555 constants. That way, doing tsubst_expr for the enumeration
7556 constants won't result in recursive calls here; we'll find
7557 the instantiation and exit above. */
7558 tsubst_enum (template_type, t, arglist);
7560 if (CLASS_TYPE_P (template_type) && is_dependent_type)
7561 /* If the type makes use of template parameters, the
7562 code that generates debugging information will crash. */
7563 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
7565 /* Possibly limit visibility based on template args. */
7566 TREE_PUBLIC (type_decl) = 1;
7567 determine_visibility (type_decl);
7573 /* Wrapper for lookup_template_class_1. */
7576 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context,
7577 int entering_scope, tsubst_flags_t complain)
7580 timevar_push (TV_TEMPLATE_INST);
7581 ret = lookup_template_class_1 (d1, arglist, in_decl, context,
7582 entering_scope, complain);
7583 timevar_pop (TV_TEMPLATE_INST);
7591 /* True when we should also visit template parameters that occur in
7592 non-deduced contexts. */
7593 bool include_nondeduced_p;
7594 struct pointer_set_t *visited;
7597 /* Called from for_each_template_parm via walk_tree. */
7600 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
7603 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
7604 tree_fn_t fn = pfd->fn;
7605 void *data = pfd->data;
7608 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
7609 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
7610 pfd->include_nondeduced_p))
7611 return error_mark_node;
7613 switch (TREE_CODE (t))
7616 if (TYPE_PTRMEMFUNC_P (t))
7622 if (!TYPE_TEMPLATE_INFO (t))
7624 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)),
7625 fn, data, pfd->visited,
7626 pfd->include_nondeduced_p))
7627 return error_mark_node;
7631 if (for_each_template_parm (TYPE_MIN_VALUE (t),
7632 fn, data, pfd->visited,
7633 pfd->include_nondeduced_p)
7634 || for_each_template_parm (TYPE_MAX_VALUE (t),
7635 fn, data, pfd->visited,
7636 pfd->include_nondeduced_p))
7637 return error_mark_node;
7641 /* Since we're not going to walk subtrees, we have to do this
7643 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
7644 pfd->visited, pfd->include_nondeduced_p))
7645 return error_mark_node;
7649 /* Check the return type. */
7650 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7651 pfd->include_nondeduced_p))
7652 return error_mark_node;
7654 /* Check the parameter types. Since default arguments are not
7655 instantiated until they are needed, the TYPE_ARG_TYPES may
7656 contain expressions that involve template parameters. But,
7657 no-one should be looking at them yet. And, once they're
7658 instantiated, they don't contain template parameters, so
7659 there's no point in looking at them then, either. */
7663 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
7664 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
7665 pfd->visited, pfd->include_nondeduced_p))
7666 return error_mark_node;
7668 /* Since we've already handled the TYPE_ARG_TYPES, we don't
7669 want walk_tree walking into them itself. */
7675 case UNDERLYING_TYPE:
7676 if (pfd->include_nondeduced_p
7677 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
7679 pfd->include_nondeduced_p))
7680 return error_mark_node;
7685 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
7686 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
7687 pfd->visited, pfd->include_nondeduced_p))
7688 return error_mark_node;
7693 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
7694 && for_each_template_parm (DECL_INITIAL (t), fn, data,
7695 pfd->visited, pfd->include_nondeduced_p))
7696 return error_mark_node;
7697 if (DECL_CONTEXT (t)
7698 && pfd->include_nondeduced_p
7699 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
7700 pfd->visited, pfd->include_nondeduced_p))
7701 return error_mark_node;
7704 case BOUND_TEMPLATE_TEMPLATE_PARM:
7705 /* Record template parameters such as `T' inside `TT<T>'. */
7706 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
7707 pfd->include_nondeduced_p))
7708 return error_mark_node;
7711 case TEMPLATE_TEMPLATE_PARM:
7712 case TEMPLATE_TYPE_PARM:
7713 case TEMPLATE_PARM_INDEX:
7714 if (fn && (*fn)(t, data))
7715 return error_mark_node;
7717 return error_mark_node;
7721 /* A template template parameter is encountered. */
7722 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
7723 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
7724 pfd->include_nondeduced_p))
7725 return error_mark_node;
7727 /* Already substituted template template parameter */
7733 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
7735 pfd->include_nondeduced_p))
7736 return error_mark_node;
7740 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
7741 && pfd->include_nondeduced_p
7742 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
7743 (TREE_TYPE (t)), fn, data,
7744 pfd->visited, pfd->include_nondeduced_p))
7745 return error_mark_node;
7750 /* If there's no type, then this thing must be some expression
7751 involving template parameters. */
7752 if (!fn && !TREE_TYPE (t))
7753 return error_mark_node;
7758 case IMPLICIT_CONV_EXPR:
7759 case REINTERPRET_CAST_EXPR:
7760 case CONST_CAST_EXPR:
7761 case STATIC_CAST_EXPR:
7762 case DYNAMIC_CAST_EXPR:
7766 case PSEUDO_DTOR_EXPR:
7768 return error_mark_node;
7775 /* We didn't find any template parameters we liked. */
7779 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
7780 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
7781 call FN with the parameter and the DATA.
7782 If FN returns nonzero, the iteration is terminated, and
7783 for_each_template_parm returns 1. Otherwise, the iteration
7784 continues. If FN never returns a nonzero value, the value
7785 returned by for_each_template_parm is 0. If FN is NULL, it is
7786 considered to be the function which always returns 1.
7788 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
7789 parameters that occur in non-deduced contexts. When false, only
7790 visits those template parameters that can be deduced. */
7793 for_each_template_parm (tree t, tree_fn_t fn, void* data,
7794 struct pointer_set_t *visited,
7795 bool include_nondeduced_p)
7797 struct pair_fn_data pfd;
7803 pfd.include_nondeduced_p = include_nondeduced_p;
7805 /* Walk the tree. (Conceptually, we would like to walk without
7806 duplicates, but for_each_template_parm_r recursively calls
7807 for_each_template_parm, so we would need to reorganize a fair
7808 bit to use walk_tree_without_duplicates, so we keep our own
7811 pfd.visited = visited;
7813 pfd.visited = pointer_set_create ();
7814 result = cp_walk_tree (&t,
7815 for_each_template_parm_r,
7817 pfd.visited) != NULL_TREE;
7822 pointer_set_destroy (pfd.visited);
7829 /* Returns true if T depends on any template parameter. */
7832 uses_template_parms (tree t)
7835 int saved_processing_template_decl;
7837 saved_processing_template_decl = processing_template_decl;
7838 if (!saved_processing_template_decl)
7839 processing_template_decl = 1;
7841 dependent_p = dependent_type_p (t);
7842 else if (TREE_CODE (t) == TREE_VEC)
7843 dependent_p = any_dependent_template_arguments_p (t);
7844 else if (TREE_CODE (t) == TREE_LIST)
7845 dependent_p = (uses_template_parms (TREE_VALUE (t))
7846 || uses_template_parms (TREE_CHAIN (t)));
7847 else if (TREE_CODE (t) == TYPE_DECL)
7848 dependent_p = dependent_type_p (TREE_TYPE (t));
7851 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
7852 || TREE_CODE (t) == OVERLOAD
7854 || TREE_CODE (t) == IDENTIFIER_NODE
7855 || TREE_CODE (t) == TRAIT_EXPR
7856 || TREE_CODE (t) == CONSTRUCTOR
7857 || CONSTANT_CLASS_P (t))
7858 dependent_p = (type_dependent_expression_p (t)
7859 || value_dependent_expression_p (t));
7862 gcc_assert (t == error_mark_node);
7863 dependent_p = false;
7866 processing_template_decl = saved_processing_template_decl;
7871 /* Returns true iff current_function_decl is an incompletely instantiated
7872 template. Useful instead of processing_template_decl because the latter
7873 is set to 0 during fold_non_dependent_expr. */
7876 in_template_function (void)
7878 tree fn = current_function_decl;
7880 ++processing_template_decl;
7881 ret = (fn && DECL_LANG_SPECIFIC (fn)
7882 && DECL_TEMPLATE_INFO (fn)
7883 && any_dependent_template_arguments_p (DECL_TI_ARGS (fn)));
7884 --processing_template_decl;
7888 /* Returns true if T depends on any template parameter with level LEVEL. */
7891 uses_template_parms_level (tree t, int level)
7893 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
7894 /*include_nondeduced_p=*/true);
7897 /* Returns TRUE iff INST is an instantiation we don't need to do in an
7898 ill-formed translation unit, i.e. a variable or function that isn't
7899 usable in a constant expression. */
7902 neglectable_inst_p (tree d)
7905 && !(TREE_CODE (d) == FUNCTION_DECL ? DECL_DECLARED_CONSTEXPR_P (d)
7906 : decl_maybe_constant_var_p (d)));
7909 /* Returns TRUE iff we should refuse to instantiate DECL because it's
7910 neglectable and instantiated from within an erroneous instantiation. */
7913 limit_bad_template_recursion (tree decl)
7915 struct tinst_level *lev = current_tinst_level;
7916 int errs = errorcount + sorrycount;
7917 if (lev == NULL || errs == 0 || !neglectable_inst_p (decl))
7920 for (; lev; lev = lev->next)
7921 if (neglectable_inst_p (lev->decl))
7924 return (lev && errs > lev->errors);
7927 static int tinst_depth;
7928 extern int max_tinst_depth;
7931 static GTY(()) struct tinst_level *last_error_tinst_level;
7933 /* We're starting to instantiate D; record the template instantiation context
7934 for diagnostics and to restore it later. */
7937 push_tinst_level (tree d)
7939 struct tinst_level *new_level;
7941 if (tinst_depth >= max_tinst_depth)
7943 last_error_tinst_level = current_tinst_level;
7944 if (TREE_CODE (d) == TREE_LIST)
7945 error ("template instantiation depth exceeds maximum of %d (use "
7946 "-ftemplate-depth= to increase the maximum) substituting %qS",
7947 max_tinst_depth, d);
7949 error ("template instantiation depth exceeds maximum of %d (use "
7950 "-ftemplate-depth= to increase the maximum) instantiating %qD",
7951 max_tinst_depth, d);
7953 print_instantiation_context ();
7958 /* If the current instantiation caused problems, don't let it instantiate
7959 anything else. Do allow deduction substitution and decls usable in
7960 constant expressions. */
7961 if (limit_bad_template_recursion (d))
7964 new_level = ggc_alloc_tinst_level ();
7965 new_level->decl = d;
7966 new_level->locus = input_location;
7967 new_level->errors = errorcount+sorrycount;
7968 new_level->in_system_header_p = in_system_header;
7969 new_level->next = current_tinst_level;
7970 current_tinst_level = new_level;
7973 if (GATHER_STATISTICS && (tinst_depth > depth_reached))
7974 depth_reached = tinst_depth;
7979 /* We're done instantiating this template; return to the instantiation
7983 pop_tinst_level (void)
7985 /* Restore the filename and line number stashed away when we started
7986 this instantiation. */
7987 input_location = current_tinst_level->locus;
7988 current_tinst_level = current_tinst_level->next;
7992 /* We're instantiating a deferred template; restore the template
7993 instantiation context in which the instantiation was requested, which
7994 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
7997 reopen_tinst_level (struct tinst_level *level)
7999 struct tinst_level *t;
8002 for (t = level; t; t = t->next)
8005 current_tinst_level = level;
8007 if (current_tinst_level)
8008 current_tinst_level->errors = errorcount+sorrycount;
8012 /* Returns the TINST_LEVEL which gives the original instantiation
8015 struct tinst_level *
8016 outermost_tinst_level (void)
8018 struct tinst_level *level = current_tinst_level;
8021 level = level->next;
8025 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
8026 vector of template arguments, as for tsubst.
8028 Returns an appropriate tsubst'd friend declaration. */
8031 tsubst_friend_function (tree decl, tree args)
8035 if (TREE_CODE (decl) == FUNCTION_DECL
8036 && DECL_TEMPLATE_INSTANTIATION (decl)
8037 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
8038 /* This was a friend declared with an explicit template
8039 argument list, e.g.:
8043 to indicate that f was a template instantiation, not a new
8044 function declaration. Now, we have to figure out what
8045 instantiation of what template. */
8047 tree template_id, arglist, fns;
8050 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
8052 /* Friend functions are looked up in the containing namespace scope.
8053 We must enter that scope, to avoid finding member functions of the
8054 current class with same name. */
8055 push_nested_namespace (ns);
8056 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
8057 tf_warning_or_error, NULL_TREE,
8058 /*integral_constant_expression_p=*/false);
8059 pop_nested_namespace (ns);
8060 arglist = tsubst (DECL_TI_ARGS (decl), args,
8061 tf_warning_or_error, NULL_TREE);
8062 template_id = lookup_template_function (fns, arglist);
8064 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8065 tmpl = determine_specialization (template_id, new_friend,
8067 /*need_member_template=*/0,
8068 TREE_VEC_LENGTH (args),
8070 return instantiate_template (tmpl, new_args, tf_error);
8073 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
8075 /* The NEW_FRIEND will look like an instantiation, to the
8076 compiler, but is not an instantiation from the point of view of
8077 the language. For example, we might have had:
8079 template <class T> struct S {
8080 template <class U> friend void f(T, U);
8083 Then, in S<int>, template <class U> void f(int, U) is not an
8084 instantiation of anything. */
8085 if (new_friend == error_mark_node)
8086 return error_mark_node;
8088 DECL_USE_TEMPLATE (new_friend) = 0;
8089 if (TREE_CODE (decl) == TEMPLATE_DECL)
8091 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
8092 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
8093 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
8096 /* The mangled name for the NEW_FRIEND is incorrect. The function
8097 is not a template instantiation and should not be mangled like
8098 one. Therefore, we forget the mangling here; we'll recompute it
8099 later if we need it. */
8100 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
8102 SET_DECL_RTL (new_friend, NULL);
8103 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
8106 if (DECL_NAMESPACE_SCOPE_P (new_friend))
8109 tree new_friend_template_info;
8110 tree new_friend_result_template_info;
8112 int new_friend_is_defn;
8114 /* We must save some information from NEW_FRIEND before calling
8115 duplicate decls since that function will free NEW_FRIEND if
8117 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
8118 new_friend_is_defn =
8119 (DECL_INITIAL (DECL_TEMPLATE_RESULT
8120 (template_for_substitution (new_friend)))
8122 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
8124 /* This declaration is a `primary' template. */
8125 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
8127 new_friend_result_template_info
8128 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
8131 new_friend_result_template_info = NULL_TREE;
8133 /* Make the init_value nonzero so pushdecl knows this is a defn. */
8134 if (new_friend_is_defn)
8135 DECL_INITIAL (new_friend) = error_mark_node;
8137 /* Inside pushdecl_namespace_level, we will push into the
8138 current namespace. However, the friend function should go
8139 into the namespace of the template. */
8140 ns = decl_namespace_context (new_friend);
8141 push_nested_namespace (ns);
8142 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
8143 pop_nested_namespace (ns);
8145 if (old_decl == error_mark_node)
8146 return error_mark_node;
8148 if (old_decl != new_friend)
8150 /* This new friend declaration matched an existing
8151 declaration. For example, given:
8153 template <class T> void f(T);
8154 template <class U> class C {
8155 template <class T> friend void f(T) {}
8158 the friend declaration actually provides the definition
8159 of `f', once C has been instantiated for some type. So,
8160 old_decl will be the out-of-class template declaration,
8161 while new_friend is the in-class definition.
8163 But, if `f' was called before this point, the
8164 instantiation of `f' will have DECL_TI_ARGS corresponding
8165 to `T' but not to `U', references to which might appear
8166 in the definition of `f'. Previously, the most general
8167 template for an instantiation of `f' was the out-of-class
8168 version; now it is the in-class version. Therefore, we
8169 run through all specialization of `f', adding to their
8170 DECL_TI_ARGS appropriately. In particular, they need a
8171 new set of outer arguments, corresponding to the
8172 arguments for this class instantiation.
8174 The same situation can arise with something like this:
8177 template <class T> class C {
8181 when `C<int>' is instantiated. Now, `f(int)' is defined
8184 if (!new_friend_is_defn)
8185 /* On the other hand, if the in-class declaration does
8186 *not* provide a definition, then we don't want to alter
8187 existing definitions. We can just leave everything
8192 tree new_template = TI_TEMPLATE (new_friend_template_info);
8193 tree new_args = TI_ARGS (new_friend_template_info);
8195 /* Overwrite whatever template info was there before, if
8196 any, with the new template information pertaining to
8198 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
8200 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
8202 /* We should have called reregister_specialization in
8204 gcc_assert (retrieve_specialization (new_template,
8208 /* Instantiate it if the global has already been used. */
8209 if (DECL_ODR_USED (old_decl))
8210 instantiate_decl (old_decl, /*defer_ok=*/true,
8211 /*expl_inst_class_mem_p=*/false);
8217 /* Indicate that the old function template is a partial
8219 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
8220 = new_friend_result_template_info;
8222 gcc_assert (new_template
8223 == most_general_template (new_template));
8224 gcc_assert (new_template != old_decl);
8226 /* Reassign any specializations already in the hash table
8227 to the new more general template, and add the
8228 additional template args. */
8229 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
8233 tree spec = TREE_VALUE (t);
8236 elt.tmpl = old_decl;
8237 elt.args = DECL_TI_ARGS (spec);
8238 elt.spec = NULL_TREE;
8240 htab_remove_elt (decl_specializations, &elt);
8243 = add_outermost_template_args (new_args,
8244 DECL_TI_ARGS (spec));
8246 register_specialization
8247 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
8250 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
8254 /* The information from NEW_FRIEND has been merged into OLD_DECL
8255 by duplicate_decls. */
8256 new_friend = old_decl;
8261 tree context = DECL_CONTEXT (new_friend);
8265 template <class T> class C {
8266 template <class U> friend void C1<U>::f (); // case 1
8267 friend void C2<T>::f (); // case 2
8269 we only need to make sure CONTEXT is a complete type for
8270 case 2. To distinguish between the two cases, we note that
8271 CONTEXT of case 1 remains dependent type after tsubst while
8272 this isn't true for case 2. */
8273 ++processing_template_decl;
8274 dependent_p = dependent_type_p (context);
8275 --processing_template_decl;
8278 && !complete_type_or_else (context, NULL_TREE))
8279 return error_mark_node;
8281 if (COMPLETE_TYPE_P (context))
8283 /* Check to see that the declaration is really present, and,
8284 possibly obtain an improved declaration. */
8285 tree fn = check_classfn (context,
8286 new_friend, NULL_TREE);
8296 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
8297 template arguments, as for tsubst.
8299 Returns an appropriate tsubst'd friend type or error_mark_node on
8303 tsubst_friend_class (tree friend_tmpl, tree args)
8309 if (DECL_TEMPLATE_TEMPLATE_PARM_P (friend_tmpl))
8311 tree t = tsubst (TREE_TYPE (friend_tmpl), args, tf_none, NULL_TREE);
8312 return TREE_TYPE (t);
8315 context = CP_DECL_CONTEXT (friend_tmpl);
8317 if (context != global_namespace)
8319 if (TREE_CODE (context) == NAMESPACE_DECL)
8320 push_nested_namespace (context);
8322 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
8325 /* Look for a class template declaration. We look for hidden names
8326 because two friend declarations of the same template are the
8327 same. For example, in:
8330 template <typename> friend class F;
8332 template <typename> struct B {
8333 template <typename> friend class F;
8336 both F templates are the same. */
8337 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
8338 /*block_p=*/true, 0, LOOKUP_HIDDEN);
8340 /* But, if we don't find one, it might be because we're in a
8341 situation like this:
8349 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
8350 for `S<int>', not the TEMPLATE_DECL. */
8351 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
8353 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
8354 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
8357 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
8359 /* The friend template has already been declared. Just
8360 check to see that the declarations match, and install any new
8361 default parameters. We must tsubst the default parameters,
8362 of course. We only need the innermost template parameters
8363 because that is all that redeclare_class_template will look
8365 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
8366 > TMPL_ARGS_DEPTH (args))
8369 location_t saved_input_location;
8370 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
8371 args, tf_warning_or_error);
8373 saved_input_location = input_location;
8374 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
8375 redeclare_class_template (TREE_TYPE (tmpl), parms);
8376 input_location = saved_input_location;
8380 friend_type = TREE_TYPE (tmpl);
8384 /* The friend template has not already been declared. In this
8385 case, the instantiation of the template class will cause the
8386 injection of this template into the global scope. */
8387 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
8388 if (tmpl == error_mark_node)
8389 return error_mark_node;
8391 /* The new TMPL is not an instantiation of anything, so we
8392 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
8393 the new type because that is supposed to be the corresponding
8394 template decl, i.e., TMPL. */
8395 DECL_USE_TEMPLATE (tmpl) = 0;
8396 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
8397 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
8398 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
8399 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
8401 /* Inject this template into the global scope. */
8402 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
8405 if (context != global_namespace)
8407 if (TREE_CODE (context) == NAMESPACE_DECL)
8408 pop_nested_namespace (context);
8410 pop_nested_class ();
8416 /* Returns zero if TYPE cannot be completed later due to circularity.
8417 Otherwise returns one. */
8420 can_complete_type_without_circularity (tree type)
8422 if (type == NULL_TREE || type == error_mark_node)
8424 else if (COMPLETE_TYPE_P (type))
8426 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
8427 return can_complete_type_without_circularity (TREE_TYPE (type));
8428 else if (CLASS_TYPE_P (type)
8429 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
8435 /* Apply any attributes which had to be deferred until instantiation
8436 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
8437 ARGS, COMPLAIN, IN_DECL are as tsubst. */
8440 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
8441 tree args, tsubst_flags_t complain, tree in_decl)
8443 tree last_dep = NULL_TREE;
8447 for (t = attributes; t; t = TREE_CHAIN (t))
8448 if (ATTR_IS_DEPENDENT (t))
8451 attributes = copy_list (attributes);
8455 if (DECL_P (*decl_p))
8457 if (TREE_TYPE (*decl_p) == error_mark_node)
8459 p = &DECL_ATTRIBUTES (*decl_p);
8462 p = &TYPE_ATTRIBUTES (*decl_p);
8466 tree late_attrs = NULL_TREE;
8467 tree *q = &late_attrs;
8469 for (*p = attributes; *p; )
8472 if (ATTR_IS_DEPENDENT (t))
8474 *p = TREE_CHAIN (t);
8475 TREE_CHAIN (t) = NULL_TREE;
8476 /* If the first attribute argument is an identifier, don't
8477 pass it through tsubst. Attributes like mode, format,
8478 cleanup and several target specific attributes expect it
8481 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
8482 && TREE_VALUE (TREE_VALUE (t))
8483 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
8484 == IDENTIFIER_NODE))
8487 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
8489 /*integral_constant_expression_p=*/false);
8490 if (chain != TREE_CHAIN (TREE_VALUE (t)))
8492 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
8497 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
8498 /*integral_constant_expression_p=*/false);
8500 q = &TREE_CHAIN (t);
8503 p = &TREE_CHAIN (t);
8506 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
8510 /* Perform (or defer) access check for typedefs that were referenced
8511 from within the template TMPL code.
8512 This is a subroutine of instantiate_decl and instantiate_class_template.
8513 TMPL is the template to consider and TARGS is the list of arguments of
8517 perform_typedefs_access_check (tree tmpl, tree targs)
8519 location_t saved_location;
8521 qualified_typedef_usage_t *iter;
8524 || (!CLASS_TYPE_P (tmpl)
8525 && TREE_CODE (tmpl) != FUNCTION_DECL))
8528 saved_location = input_location;
8529 FOR_EACH_VEC_SAFE_ELT (get_types_needing_access_check (tmpl), i, iter)
8531 tree type_decl = iter->typedef_decl;
8532 tree type_scope = iter->context;
8534 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
8537 if (uses_template_parms (type_decl))
8538 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
8539 if (uses_template_parms (type_scope))
8540 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
8542 /* Make access check error messages point to the location
8543 of the use of the typedef. */
8544 input_location = iter->locus;
8545 perform_or_defer_access_check (TYPE_BINFO (type_scope),
8546 type_decl, type_decl,
8547 tf_warning_or_error);
8549 input_location = saved_location;
8553 instantiate_class_template_1 (tree type)
8555 tree templ, args, pattern, t, member;
8559 unsigned int saved_maximum_field_alignment;
8562 if (type == error_mark_node)
8563 return error_mark_node;
8565 if (COMPLETE_OR_OPEN_TYPE_P (type)
8566 || uses_template_parms (type))
8569 /* Figure out which template is being instantiated. */
8570 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
8571 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
8573 /* Determine what specialization of the original template to
8575 t = most_specialized_class (type, templ, tf_warning_or_error);
8576 if (t == error_mark_node)
8578 TYPE_BEING_DEFINED (type) = 1;
8579 return error_mark_node;
8583 /* This TYPE is actually an instantiation of a partial
8584 specialization. We replace the innermost set of ARGS with
8585 the arguments appropriate for substitution. For example,
8588 template <class T> struct S {};
8589 template <class T> struct S<T*> {};
8591 and supposing that we are instantiating S<int*>, ARGS will
8592 presently be {int*} -- but we need {int}. */
8593 pattern = TREE_TYPE (t);
8594 args = TREE_PURPOSE (t);
8598 pattern = TREE_TYPE (templ);
8599 args = CLASSTYPE_TI_ARGS (type);
8602 /* If the template we're instantiating is incomplete, then clearly
8603 there's nothing we can do. */
8604 if (!COMPLETE_TYPE_P (pattern))
8607 /* If we've recursively instantiated too many templates, stop. */
8608 if (! push_tinst_level (type))
8611 /* Now we're really doing the instantiation. Mark the type as in
8612 the process of being defined. */
8613 TYPE_BEING_DEFINED (type) = 1;
8615 /* We may be in the middle of deferred access check. Disable
8617 push_deferring_access_checks (dk_no_deferred);
8619 fn_context = decl_function_context (TYPE_MAIN_DECL (type));
8621 push_to_top_level ();
8622 /* Use #pragma pack from the template context. */
8623 saved_maximum_field_alignment = maximum_field_alignment;
8624 maximum_field_alignment = TYPE_PRECISION (pattern);
8626 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
8628 /* Set the input location to the most specialized template definition.
8629 This is needed if tsubsting causes an error. */
8630 typedecl = TYPE_MAIN_DECL (pattern);
8631 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) =
8632 DECL_SOURCE_LOCATION (typedecl);
8634 TYPE_PACKED (type) = TYPE_PACKED (pattern);
8635 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
8636 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
8637 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
8638 if (ANON_AGGR_TYPE_P (pattern))
8639 SET_ANON_AGGR_TYPE_P (type);
8640 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
8642 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
8643 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
8644 /* Adjust visibility for template arguments. */
8645 determine_visibility (TYPE_MAIN_DECL (type));
8647 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern);
8649 pbinfo = TYPE_BINFO (pattern);
8651 /* We should never instantiate a nested class before its enclosing
8652 class; we need to look up the nested class by name before we can
8653 instantiate it, and that lookup should instantiate the enclosing
8655 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
8656 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type)));
8658 base_list = NULL_TREE;
8659 if (BINFO_N_BASE_BINFOS (pbinfo))
8665 /* We must enter the scope containing the type, as that is where
8666 the accessibility of types named in dependent bases are
8668 pushed_scope = push_scope (CP_TYPE_CONTEXT (type));
8670 /* Substitute into each of the bases to determine the actual
8672 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
8675 tree access = BINFO_BASE_ACCESS (pbinfo, i);
8676 tree expanded_bases = NULL_TREE;
8679 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
8682 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
8683 args, tf_error, NULL_TREE);
8684 if (expanded_bases == error_mark_node)
8687 len = TREE_VEC_LENGTH (expanded_bases);
8690 for (idx = 0; idx < len; idx++)
8693 /* Extract the already-expanded base class. */
8694 base = TREE_VEC_ELT (expanded_bases, idx);
8696 /* Substitute to figure out the base class. */
8697 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
8700 if (base == error_mark_node)
8703 base_list = tree_cons (access, base, base_list);
8704 if (BINFO_VIRTUAL_P (pbase_binfo))
8705 TREE_TYPE (base_list) = integer_type_node;
8709 /* The list is now in reverse order; correct that. */
8710 base_list = nreverse (base_list);
8713 pop_scope (pushed_scope);
8715 /* Now call xref_basetypes to set up all the base-class
8717 xref_basetypes (type, base_list);
8719 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
8720 (int) ATTR_FLAG_TYPE_IN_PLACE,
8721 args, tf_error, NULL_TREE);
8722 fixup_attribute_variants (type);
8724 /* Now that our base classes are set up, enter the scope of the
8725 class, so that name lookups into base classes, etc. will work
8726 correctly. This is precisely analogous to what we do in
8727 begin_class_definition when defining an ordinary non-template
8728 class, except we also need to push the enclosing classes. */
8729 push_nested_class (type);
8731 /* Now members are processed in the order of declaration. */
8732 for (member = CLASSTYPE_DECL_LIST (pattern);
8733 member; member = TREE_CHAIN (member))
8735 tree t = TREE_VALUE (member);
8737 if (TREE_PURPOSE (member))
8741 /* Build new CLASSTYPE_NESTED_UTDS. */
8744 bool class_template_p;
8746 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
8747 && TYPE_LANG_SPECIFIC (t)
8748 && CLASSTYPE_IS_TEMPLATE (t));
8749 /* If the member is a class template, then -- even after
8750 substitution -- there may be dependent types in the
8751 template argument list for the class. We increment
8752 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
8753 that function will assume that no types are dependent
8754 when outside of a template. */
8755 if (class_template_p)
8756 ++processing_template_decl;
8757 newtag = tsubst (t, args, tf_error, NULL_TREE);
8758 if (class_template_p)
8759 --processing_template_decl;
8760 if (newtag == error_mark_node)
8763 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
8765 tree name = TYPE_IDENTIFIER (t);
8767 if (class_template_p)
8768 /* Unfortunately, lookup_template_class sets
8769 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
8770 instantiation (i.e., for the type of a member
8771 template class nested within a template class.)
8772 This behavior is required for
8773 maybe_process_partial_specialization to work
8774 correctly, but is not accurate in this case;
8775 the TAG is not an instantiation of anything.
8776 (The corresponding TEMPLATE_DECL is an
8777 instantiation, but the TYPE is not.) */
8778 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
8780 /* Now, we call pushtag to put this NEWTAG into the scope of
8781 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
8782 pushtag calling push_template_decl. We don't have to do
8783 this for enums because it will already have been done in
8786 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
8787 pushtag (name, newtag, /*tag_scope=*/ts_current);
8790 else if (TREE_CODE (t) == FUNCTION_DECL
8791 || DECL_FUNCTION_TEMPLATE_P (t))
8793 /* Build new TYPE_METHODS. */
8796 if (TREE_CODE (t) == TEMPLATE_DECL)
8797 ++processing_template_decl;
8798 r = tsubst (t, args, tf_error, NULL_TREE);
8799 if (TREE_CODE (t) == TEMPLATE_DECL)
8800 --processing_template_decl;
8801 set_current_access_from_decl (r);
8802 finish_member_declaration (r);
8803 /* Instantiate members marked with attribute used. */
8804 if (r != error_mark_node && DECL_PRESERVE_P (r))
8809 /* Build new TYPE_FIELDS. */
8810 if (TREE_CODE (t) == STATIC_ASSERT)
8814 ++c_inhibit_evaluation_warnings;
8816 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
8817 tf_warning_or_error, NULL_TREE,
8818 /*integral_constant_expression_p=*/true);
8819 --c_inhibit_evaluation_warnings;
8821 finish_static_assert (condition,
8822 STATIC_ASSERT_MESSAGE (t),
8823 STATIC_ASSERT_SOURCE_LOCATION (t),
8826 else if (TREE_CODE (t) != CONST_DECL)
8830 /* The file and line for this declaration, to
8831 assist in error message reporting. Since we
8832 called push_tinst_level above, we don't need to
8834 input_location = DECL_SOURCE_LOCATION (t);
8836 if (TREE_CODE (t) == TEMPLATE_DECL)
8837 ++processing_template_decl;
8838 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
8839 if (TREE_CODE (t) == TEMPLATE_DECL)
8840 --processing_template_decl;
8841 if (TREE_CODE (r) == VAR_DECL)
8845 [t]he initialization (and any associated
8846 side-effects) of a static data member does
8847 not occur unless the static data member is
8848 itself used in a way that requires the
8849 definition of the static data member to
8852 Therefore, we do not substitute into the
8853 initialized for the static data member here. */
8854 finish_static_data_member_decl
8857 /*init_const_expr_p=*/false,
8858 /*asmspec_tree=*/NULL_TREE,
8860 /* Instantiate members marked with attribute used. */
8861 if (r != error_mark_node && DECL_PRESERVE_P (r))
8864 else if (TREE_CODE (r) == FIELD_DECL)
8866 /* Determine whether R has a valid type and can be
8867 completed later. If R is invalid, then it is
8868 replaced by error_mark_node so that it will not be
8869 added to TYPE_FIELDS. */
8870 tree rtype = TREE_TYPE (r);
8871 if (can_complete_type_without_circularity (rtype))
8872 complete_type (rtype);
8874 if (!COMPLETE_TYPE_P (rtype))
8876 cxx_incomplete_type_error (r, rtype);
8877 r = error_mark_node;
8881 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
8882 such a thing will already have been added to the field
8883 list by tsubst_enum in finish_member_declaration in the
8884 CLASSTYPE_NESTED_UTDS case above. */
8885 if (!(TREE_CODE (r) == TYPE_DECL
8886 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
8887 && DECL_ARTIFICIAL (r)))
8889 set_current_access_from_decl (r);
8890 finish_member_declaration (r);
8897 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t)
8898 || DECL_TEMPLATE_TEMPLATE_PARM_P (t))
8900 /* Build new CLASSTYPE_FRIEND_CLASSES. */
8902 tree friend_type = t;
8903 bool adjust_processing_template_decl = false;
8905 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8907 /* template <class T> friend class C; */
8908 friend_type = tsubst_friend_class (friend_type, args);
8909 adjust_processing_template_decl = true;
8911 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
8913 /* template <class T> friend class C::D; */
8914 friend_type = tsubst (friend_type, args,
8915 tf_warning_or_error, NULL_TREE);
8916 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
8917 friend_type = TREE_TYPE (friend_type);
8918 adjust_processing_template_decl = true;
8920 else if (TREE_CODE (friend_type) == TYPENAME_TYPE
8921 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM)
8923 /* This could be either
8927 when dependent_type_p is false or
8929 template <class U> friend class T::C;
8932 friend_type = tsubst (friend_type, args,
8933 tf_warning_or_error, NULL_TREE);
8934 /* Bump processing_template_decl for correct
8935 dependent_type_p calculation. */
8936 ++processing_template_decl;
8937 if (dependent_type_p (friend_type))
8938 adjust_processing_template_decl = true;
8939 --processing_template_decl;
8941 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
8942 && hidden_name_p (TYPE_NAME (friend_type)))
8946 where C hasn't been declared yet. Let's lookup name
8947 from namespace scope directly, bypassing any name that
8948 come from dependent base class. */
8949 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
8951 /* The call to xref_tag_from_type does injection for friend
8953 push_nested_namespace (ns);
8955 xref_tag_from_type (friend_type, NULL_TREE,
8956 /*tag_scope=*/ts_current);
8957 pop_nested_namespace (ns);
8959 else if (uses_template_parms (friend_type))
8960 /* friend class C<T>; */
8961 friend_type = tsubst (friend_type, args,
8962 tf_warning_or_error, NULL_TREE);
8967 where C is already declared or
8969 friend class C<int>;
8971 We don't have to do anything in these cases. */
8973 if (adjust_processing_template_decl)
8974 /* Trick make_friend_class into realizing that the friend
8975 we're adding is a template, not an ordinary class. It's
8976 important that we use make_friend_class since it will
8977 perform some error-checking and output cross-reference
8979 ++processing_template_decl;
8981 if (friend_type != error_mark_node)
8982 make_friend_class (type, friend_type, /*complain=*/false);
8984 if (adjust_processing_template_decl)
8985 --processing_template_decl;
8989 /* Build new DECL_FRIENDLIST. */
8992 /* The file and line for this declaration, to
8993 assist in error message reporting. Since we
8994 called push_tinst_level above, we don't need to
8996 input_location = DECL_SOURCE_LOCATION (t);
8998 if (TREE_CODE (t) == TEMPLATE_DECL)
9000 ++processing_template_decl;
9001 push_deferring_access_checks (dk_no_check);
9004 r = tsubst_friend_function (t, args);
9005 add_friend (type, r, /*complain=*/false);
9006 if (TREE_CODE (t) == TEMPLATE_DECL)
9008 pop_deferring_access_checks ();
9009 --processing_template_decl;
9015 if (tree expr = CLASSTYPE_LAMBDA_EXPR (type))
9017 tree decl = lambda_function (type);
9020 instantiate_decl (decl, false, false);
9022 /* We need to instantiate the capture list from the template
9023 after we've instantiated the closure members, but before we
9024 consider adding the conversion op. Also keep any captures
9025 that may have been added during instantiation of the op(). */
9026 tree tmpl_expr = CLASSTYPE_LAMBDA_EXPR (pattern);
9028 = tsubst_copy_and_build (LAMBDA_EXPR_CAPTURE_LIST (tmpl_expr),
9029 args, tf_warning_or_error, NULL_TREE,
9032 LAMBDA_EXPR_CAPTURE_LIST (expr)
9033 = chainon (tmpl_cap, nreverse (LAMBDA_EXPR_CAPTURE_LIST (expr)));
9035 maybe_add_lambda_conv_op (type);
9038 gcc_assert (errorcount);
9041 /* Set the file and line number information to whatever is given for
9042 the class itself. This puts error messages involving generated
9043 implicit functions at a predictable point, and the same point
9044 that would be used for non-template classes. */
9045 input_location = DECL_SOURCE_LOCATION (typedecl);
9047 unreverse_member_declarations (type);
9048 finish_struct_1 (type);
9049 TYPE_BEING_DEFINED (type) = 0;
9051 /* We don't instantiate default arguments for member functions. 14.7.1:
9053 The implicit instantiation of a class template specialization causes
9054 the implicit instantiation of the declarations, but not of the
9055 definitions or default arguments, of the class member functions,
9056 member classes, static data members and member templates.... */
9058 /* Some typedefs referenced from within the template code need to be access
9059 checked at template instantiation time, i.e now. These types were
9060 added to the template at parsing time. Let's get those and perform
9061 the access checks then. */
9062 perform_typedefs_access_check (pattern, args);
9063 perform_deferred_access_checks (tf_warning_or_error);
9064 pop_nested_class ();
9065 maximum_field_alignment = saved_maximum_field_alignment;
9067 pop_from_top_level ();
9068 pop_deferring_access_checks ();
9071 /* The vtable for a template class can be emitted in any translation
9072 unit in which the class is instantiated. When there is no key
9073 method, however, finish_struct_1 will already have added TYPE to
9074 the keyed_classes list. */
9075 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
9076 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
9081 /* Wrapper for instantiate_class_template_1. */
9084 instantiate_class_template (tree type)
9087 timevar_push (TV_TEMPLATE_INST);
9088 ret = instantiate_class_template_1 (type);
9089 timevar_pop (TV_TEMPLATE_INST);
9094 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9100 else if (TYPE_P (t))
9101 r = tsubst (t, args, complain, in_decl);
9104 if (!(complain & tf_warning))
9105 ++c_inhibit_evaluation_warnings;
9106 r = tsubst_expr (t, args, complain, in_decl,
9107 /*integral_constant_expression_p=*/true);
9108 if (!(complain & tf_warning))
9109 --c_inhibit_evaluation_warnings;
9110 /* Preserve the raw-reference nature of T. */
9111 if (TREE_TYPE (t) && TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE
9112 && REFERENCE_REF_P (r))
9113 r = TREE_OPERAND (r, 0);
9118 /* Given a function parameter pack TMPL_PARM and some function parameters
9119 instantiated from it at *SPEC_P, return a NONTYPE_ARGUMENT_PACK of them
9120 and set *SPEC_P to point at the next point in the list. */
9123 extract_fnparm_pack (tree tmpl_parm, tree *spec_p)
9125 /* Collect all of the extra "packed" parameters into an
9129 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
9130 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK);
9131 tree spec_parm = *spec_p;
9134 for (len = 0; spec_parm; ++len, spec_parm = TREE_CHAIN (spec_parm))
9136 && !function_parameter_expanded_from_pack_p (spec_parm, tmpl_parm))
9139 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
9140 parmvec = make_tree_vec (len);
9141 parmtypevec = make_tree_vec (len);
9142 spec_parm = *spec_p;
9143 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm))
9145 TREE_VEC_ELT (parmvec, i) = spec_parm;
9146 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
9149 /* Build the argument packs. */
9150 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
9151 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
9152 TREE_TYPE (argpack) = argtypepack;
9153 *spec_p = spec_parm;
9158 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
9159 NONTYPE_ARGUMENT_PACK. */
9162 make_fnparm_pack (tree spec_parm)
9164 return extract_fnparm_pack (NULL_TREE, &spec_parm);
9167 /* Return true iff the Ith element of the argument pack ARG_PACK is a
9171 argument_pack_element_is_expansion_p (tree arg_pack, int i)
9173 tree vec = ARGUMENT_PACK_ARGS (arg_pack);
9174 if (i >= TREE_VEC_LENGTH (vec))
9176 return PACK_EXPANSION_P (TREE_VEC_ELT (vec, i));
9180 /* Creates and return an ARGUMENT_PACK_SELECT tree node. */
9183 make_argument_pack_select (tree arg_pack, unsigned index)
9185 tree aps = make_node (ARGUMENT_PACK_SELECT);
9187 ARGUMENT_PACK_SELECT_FROM_PACK (aps) = arg_pack;
9188 ARGUMENT_PACK_SELECT_INDEX (aps) = index;
9193 /* This is a subroutine of tsubst_pack_expansion.
9195 It returns TRUE if we need to use the PACK_EXPANSION_EXTRA_ARGS
9196 mechanism to store the (non complete list of) arguments of the
9197 substitution and return a non substituted pack expansion, in order
9198 to wait for when we have enough arguments to really perform the
9202 use_pack_expansion_extra_args_p (tree parm_packs,
9206 /* If one pack has an expansion and another pack has a normal
9207 argument or if one pack has an empty argument and an another
9208 one hasn't then tsubst_pack_expansion cannot perform the
9209 substitution and need to fall back on the
9210 PACK_EXPANSION_EXTRA mechanism. */
9211 if (parm_packs == NULL_TREE)
9213 else if (has_empty_arg)
9216 bool has_expansion_arg = false;
9217 for (int i = 0 ; i < arg_pack_len; ++i)
9219 bool has_non_expansion_arg = false;
9220 for (tree parm_pack = parm_packs;
9222 parm_pack = TREE_CHAIN (parm_pack))
9224 tree arg = TREE_VALUE (parm_pack);
9226 if (argument_pack_element_is_expansion_p (arg, i))
9227 has_expansion_arg = true;
9229 has_non_expansion_arg = true;
9232 if (has_expansion_arg && has_non_expansion_arg)
9238 /* [temp.variadic]/6 says that:
9240 The instantiation of a pack expansion [...]
9241 produces a list E1,E2, ..., En, where N is the number of elements
9242 in the pack expansion parameters.
9244 This subroutine of tsubst_pack_expansion produces one of these Ei.
9246 PATTERN is the pattern of the pack expansion. PARM_PACKS is a
9247 TREE_LIST in which each TREE_PURPOSE is a parameter pack of
9248 PATTERN, and each TREE_VALUE is its corresponding argument pack.
9249 INDEX is the index 'i' of the element Ei to produce. ARGS,
9250 COMPLAIN, and IN_DECL are the same parameters as for the
9251 tsubst_pack_expansion function.
9253 The function returns the resulting Ei upon successful completion,
9256 Note that this function possibly modifies the ARGS parameter, so
9257 it's the responsibility of the caller to restore it. */
9260 gen_elem_of_pack_expansion_instantiation (tree pattern,
9263 tree args /* This parm gets
9265 tsubst_flags_t complain,
9269 bool ith_elem_is_expansion = false;
9271 /* For each parameter pack, change the substitution of the parameter
9272 pack to the ith argument in its argument pack, then expand the
9274 for (tree pack = parm_packs; pack; pack = TREE_CHAIN (pack))
9276 tree parm = TREE_PURPOSE (pack);
9277 tree arg_pack = TREE_VALUE (pack);
9278 tree aps; /* instance of ARGUMENT_PACK_SELECT. */
9280 ith_elem_is_expansion |=
9281 argument_pack_element_is_expansion_p (arg_pack, index);
9283 /* Select the Ith argument from the pack. */
9284 if (TREE_CODE (parm) == PARM_DECL)
9288 aps = make_argument_pack_select (arg_pack, index);
9290 register_local_specialization (aps, parm);
9293 aps = retrieve_local_specialization (parm);
9298 template_parm_level_and_index (parm, &level, &idx);
9302 aps = make_argument_pack_select (arg_pack, index);
9303 /* Update the corresponding argument. */
9304 TMPL_ARG (args, level, idx) = aps;
9307 /* Re-use the ARGUMENT_PACK_SELECT. */
9308 aps = TMPL_ARG (args, level, idx);
9310 ARGUMENT_PACK_SELECT_INDEX (aps) = index;
9313 /* Substitute into the PATTERN with the (possibly altered)
9315 if (!TYPE_P (pattern))
9316 t = tsubst_expr (pattern, args, complain, in_decl,
9317 /*integral_constant_expression_p=*/false);
9319 t = tsubst (pattern, args, complain, in_decl);
9321 /* If the Ith argument pack element is a pack expansion, then
9322 the Ith element resulting from the substituting is going to
9323 be a pack expansion as well. */
9324 if (ith_elem_is_expansion)
9325 t = make_pack_expansion (t);
9330 /* Substitute ARGS into T, which is an pack expansion
9331 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
9332 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
9333 (if only a partial substitution could be performed) or
9334 ERROR_MARK_NODE if there was an error. */
9336 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
9340 tree pack, packs = NULL_TREE;
9341 bool unsubstituted_packs = false;
9344 struct pointer_map_t *saved_local_specializations = NULL;
9345 bool need_local_specializations = false;
9348 gcc_assert (PACK_EXPANSION_P (t));
9349 pattern = PACK_EXPANSION_PATTERN (t);
9351 /* Add in any args remembered from an earlier partial instantiation. */
9352 args = add_to_template_args (PACK_EXPANSION_EXTRA_ARGS (t), args);
9354 levels = TMPL_ARGS_DEPTH (args);
9356 /* Determine the argument packs that will instantiate the parameter
9357 packs used in the expansion expression. While we're at it,
9358 compute the number of arguments to be expanded and make sure it
9360 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
9361 pack = TREE_CHAIN (pack))
9363 tree parm_pack = TREE_VALUE (pack);
9364 tree arg_pack = NULL_TREE;
9365 tree orig_arg = NULL_TREE;
9368 if (TREE_CODE (parm_pack) == BASES)
9370 if (BASES_DIRECT (parm_pack))
9371 return calculate_direct_bases (tsubst_expr (BASES_TYPE (parm_pack),
9372 args, complain, in_decl, false));
9374 return calculate_bases (tsubst_expr (BASES_TYPE (parm_pack),
9375 args, complain, in_decl, false));
9377 if (TREE_CODE (parm_pack) == PARM_DECL)
9379 if (PACK_EXPANSION_LOCAL_P (t))
9380 arg_pack = retrieve_local_specialization (parm_pack);
9383 /* We can't rely on local_specializations for a parameter
9384 name used later in a function declaration (such as in a
9385 late-specified return type). Even if it exists, it might
9386 have the wrong value for a recursive call. Just make a
9387 dummy decl, since it's only used for its type. */
9388 arg_pack = tsubst_decl (parm_pack, args, complain);
9389 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack))
9390 /* Partial instantiation of the parm_pack, we can't build
9391 up an argument pack yet. */
9392 arg_pack = NULL_TREE;
9394 arg_pack = make_fnparm_pack (arg_pack);
9395 need_local_specializations = true;
9401 template_parm_level_and_index (parm_pack, &level, &idx);
9403 if (level <= levels)
9404 arg_pack = TMPL_ARG (args, level, idx);
9407 orig_arg = arg_pack;
9408 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
9409 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
9411 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
9412 /* This can only happen if we forget to expand an argument
9413 pack somewhere else. Just return an error, silently. */
9415 result = make_tree_vec (1);
9416 TREE_VEC_ELT (result, 0) = error_mark_node;
9423 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
9425 /* Don't bother trying to do a partial substitution with
9426 incomplete packs; we'll try again after deduction. */
9427 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
9432 else if (len != my_len)
9434 if (!(complain & tf_error))
9435 /* Fail quietly. */;
9436 else if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
9437 error ("mismatched argument pack lengths while expanding "
9441 error ("mismatched argument pack lengths while expanding "
9444 return error_mark_node;
9447 /* Keep track of the parameter packs and their corresponding
9449 packs = tree_cons (parm_pack, arg_pack, packs);
9450 TREE_TYPE (packs) = orig_arg;
9454 /* We can't substitute for this parameter pack. We use a flag as
9455 well as the missing_level counter because function parameter
9456 packs don't have a level. */
9457 unsubstituted_packs = true;
9461 /* We cannot expand this expansion expression, because we don't have
9462 all of the argument packs we need. */
9463 if (use_pack_expansion_extra_args_p (packs, len, unsubstituted_packs))
9465 /* We got some full packs, but we can't substitute them in until we
9466 have values for all the packs. So remember these until then. */
9468 t = make_pack_expansion (pattern);
9469 PACK_EXPANSION_EXTRA_ARGS (t) = args;
9472 else if (unsubstituted_packs)
9474 /* There were no real arguments, we're just replacing a parameter
9475 pack with another version of itself. Substitute into the
9476 pattern and return a PACK_EXPANSION_*. The caller will need to
9478 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
9479 t = tsubst_expr (pattern, args, complain, in_decl,
9480 /*integral_constant_expression_p=*/false);
9482 t = tsubst (pattern, args, complain, in_decl);
9483 t = make_pack_expansion (t);
9487 gcc_assert (len >= 0);
9489 if (need_local_specializations)
9491 /* We're in a late-specified return type, so create our own local
9492 specializations map; the current map is either NULL or (in the
9493 case of recursive unification) might have bindings that we don't
9494 want to use or alter. */
9495 saved_local_specializations = local_specializations;
9496 local_specializations = pointer_map_create ();
9499 /* For each argument in each argument pack, substitute into the
9501 result = make_tree_vec (len);
9502 for (i = 0; i < len; ++i)
9504 t = gen_elem_of_pack_expansion_instantiation (pattern, packs,
9508 TREE_VEC_ELT (result, i) = t;
9509 if (t == error_mark_node)
9511 result = error_mark_node;
9516 /* Update ARGS to restore the substitution from parameter packs to
9517 their argument packs. */
9518 for (pack = packs; pack; pack = TREE_CHAIN (pack))
9520 tree parm = TREE_PURPOSE (pack);
9522 if (TREE_CODE (parm) == PARM_DECL)
9523 register_local_specialization (TREE_TYPE (pack), parm);
9528 if (TREE_VALUE (pack) == NULL_TREE)
9531 template_parm_level_and_index (parm, &level, &idx);
9533 /* Update the corresponding argument. */
9534 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
9535 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
9538 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
9542 if (need_local_specializations)
9544 pointer_map_destroy (local_specializations);
9545 local_specializations = saved_local_specializations;
9551 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template
9552 TMPL. We do this using DECL_PARM_INDEX, which should work even with
9553 parameter packs; all parms generated from a function parameter pack will
9554 have the same DECL_PARM_INDEX. */
9557 get_pattern_parm (tree parm, tree tmpl)
9559 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
9562 if (DECL_ARTIFICIAL (parm))
9564 for (patparm = DECL_ARGUMENTS (pattern);
9565 patparm; patparm = DECL_CHAIN (patparm))
9566 if (DECL_ARTIFICIAL (patparm)
9567 && DECL_NAME (parm) == DECL_NAME (patparm))
9572 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl));
9573 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm);
9574 gcc_assert (DECL_PARM_INDEX (patparm)
9575 == DECL_PARM_INDEX (parm));
9581 /* Substitute ARGS into the vector or list of template arguments T. */
9584 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9587 int len, need_new = 0, i, expanded_len_adjust = 0, out;
9590 if (t == error_mark_node)
9591 return error_mark_node;
9593 len = TREE_VEC_LENGTH (t);
9594 elts = XALLOCAVEC (tree, len);
9596 for (i = 0; i < len; i++)
9598 tree orig_arg = TREE_VEC_ELT (t, i);
9601 if (TREE_CODE (orig_arg) == TREE_VEC)
9602 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
9603 else if (PACK_EXPANSION_P (orig_arg))
9605 /* Substitute into an expansion expression. */
9606 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
9608 if (TREE_CODE (new_arg) == TREE_VEC)
9609 /* Add to the expanded length adjustment the number of
9610 expanded arguments. We subtract one from this
9611 measurement, because the argument pack expression
9612 itself is already counted as 1 in
9613 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
9614 the argument pack is empty. */
9615 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
9617 else if (ARGUMENT_PACK_P (orig_arg))
9619 /* Substitute into each of the arguments. */
9620 new_arg = TYPE_P (orig_arg)
9621 ? cxx_make_type (TREE_CODE (orig_arg))
9622 : make_node (TREE_CODE (orig_arg));
9624 SET_ARGUMENT_PACK_ARGS (
9626 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
9627 args, complain, in_decl));
9629 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
9630 new_arg = error_mark_node;
9632 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
9633 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
9635 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
9637 if (TREE_TYPE (new_arg) == error_mark_node)
9638 new_arg = error_mark_node;
9642 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
9644 if (new_arg == error_mark_node)
9645 return error_mark_node;
9648 if (new_arg != orig_arg)
9655 /* Make space for the expanded arguments coming from template
9657 t = make_tree_vec (len + expanded_len_adjust);
9658 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the
9659 arguments for a member template.
9660 In that case each TREE_VEC in ORIG_T represents a level of template
9661 arguments, and ORIG_T won't carry any non defaulted argument count.
9662 It will rather be the nested TREE_VECs that will carry one.
9663 In other words, ORIG_T carries a non defaulted argument count only
9664 if it doesn't contain any nested TREE_VEC. */
9665 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t))
9667 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t);
9668 count += expanded_len_adjust;
9669 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count);
9671 for (i = 0, out = 0; i < len; i++)
9673 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
9674 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
9675 && TREE_CODE (elts[i]) == TREE_VEC)
9679 /* Now expand the template argument pack "in place". */
9680 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
9681 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
9685 TREE_VEC_ELT (t, out) = elts[i];
9693 /* Return the result of substituting ARGS into the template parameters
9694 given by PARMS. If there are m levels of ARGS and m + n levels of
9695 PARMS, then the result will contain n levels of PARMS. For
9696 example, if PARMS is `template <class T> template <class U>
9697 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
9698 result will be `template <int*, double, class V>'. */
9701 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
9706 /* When substituting into a template, we must set
9707 PROCESSING_TEMPLATE_DECL as the template parameters may be
9708 dependent if they are based on one-another, and the dependency
9709 predicates are short-circuit outside of templates. */
9710 ++processing_template_decl;
9712 for (new_parms = &r;
9713 parms && TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
9714 new_parms = &(TREE_CHAIN (*new_parms)),
9715 parms = TREE_CHAIN (parms))
9718 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
9721 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
9725 if (parms == error_mark_node)
9728 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
9730 if (tuple == error_mark_node)
9733 TREE_VEC_ELT (new_vec, i) =
9734 tsubst_template_parm (tuple, args, complain);
9738 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
9739 - TMPL_ARGS_DEPTH (args)),
9740 new_vec, NULL_TREE);
9743 --processing_template_decl;
9748 /* Return the result of substituting ARGS into one template parameter
9749 given by T. T Must be a TREE_LIST which TREE_VALUE is the template
9750 parameter and which TREE_PURPOSE is the default argument of the
9751 template parameter. */
9754 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain)
9756 tree default_value, parm_decl;
9758 if (args == NULL_TREE
9760 || t == error_mark_node)
9763 gcc_assert (TREE_CODE (t) == TREE_LIST);
9765 default_value = TREE_PURPOSE (t);
9766 parm_decl = TREE_VALUE (t);
9768 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
9769 if (TREE_CODE (parm_decl) == PARM_DECL
9770 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
9771 parm_decl = error_mark_node;
9772 default_value = tsubst_template_arg (default_value, args,
9773 complain, NULL_TREE);
9775 return build_tree_list (default_value, parm_decl);
9778 /* Substitute the ARGS into the indicated aggregate (or enumeration)
9779 type T. If T is not an aggregate or enumeration type, it is
9780 handled as if by tsubst. IN_DECL is as for tsubst. If
9781 ENTERING_SCOPE is nonzero, T is the context for a template which
9782 we are presently tsubst'ing. Return the substituted value. */
9785 tsubst_aggr_type (tree t,
9787 tsubst_flags_t complain,
9794 switch (TREE_CODE (t))
9797 if (TYPE_PTRMEMFUNC_P (t))
9798 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
9800 /* Else fall through. */
9803 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
9808 int saved_unevaluated_operand;
9809 int saved_inhibit_evaluation_warnings;
9811 /* In "sizeof(X<I>)" we need to evaluate "I". */
9812 saved_unevaluated_operand = cp_unevaluated_operand;
9813 cp_unevaluated_operand = 0;
9814 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
9815 c_inhibit_evaluation_warnings = 0;
9817 /* First, determine the context for the type we are looking
9819 context = TYPE_CONTEXT (t);
9820 if (context && TYPE_P (context))
9822 context = tsubst_aggr_type (context, args, complain,
9823 in_decl, /*entering_scope=*/1);
9824 /* If context is a nested class inside a class template,
9825 it may still need to be instantiated (c++/33959). */
9826 context = complete_type (context);
9829 /* Then, figure out what arguments are appropriate for the
9830 type we are trying to find. For example, given:
9832 template <class T> struct S;
9833 template <class T, class U> void f(T, U) { S<U> su; }
9835 and supposing that we are instantiating f<int, double>,
9836 then our ARGS will be {int, double}, but, when looking up
9837 S we only want {double}. */
9838 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
9840 if (argvec == error_mark_node)
9841 r = error_mark_node;
9844 r = lookup_template_class (t, argvec, in_decl, context,
9845 entering_scope, complain);
9846 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
9849 cp_unevaluated_operand = saved_unevaluated_operand;
9850 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
9855 /* This is not a template type, so there's nothing to do. */
9859 return tsubst (t, args, complain, in_decl);
9863 /* Substitute into the default argument ARG (a default argument for
9864 FN), which has the indicated TYPE. */
9867 tsubst_default_argument (tree fn, tree type, tree arg, tsubst_flags_t complain)
9869 tree saved_class_ptr = NULL_TREE;
9870 tree saved_class_ref = NULL_TREE;
9871 int errs = errorcount + sorrycount;
9873 /* This can happen in invalid code. */
9874 if (TREE_CODE (arg) == DEFAULT_ARG)
9877 /* This default argument came from a template. Instantiate the
9878 default argument here, not in tsubst. In the case of
9887 we must be careful to do name lookup in the scope of S<T>,
9888 rather than in the current class. */
9889 push_access_scope (fn);
9890 /* The "this" pointer is not valid in a default argument. */
9893 saved_class_ptr = current_class_ptr;
9894 cp_function_chain->x_current_class_ptr = NULL_TREE;
9895 saved_class_ref = current_class_ref;
9896 cp_function_chain->x_current_class_ref = NULL_TREE;
9899 push_deferring_access_checks(dk_no_deferred);
9900 /* The default argument expression may cause implicitly defined
9901 member functions to be synthesized, which will result in garbage
9902 collection. We must treat this situation as if we were within
9903 the body of function so as to avoid collecting live data on the
9906 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
9907 complain, NULL_TREE,
9908 /*integral_constant_expression_p=*/false);
9910 pop_deferring_access_checks();
9912 /* Restore the "this" pointer. */
9915 cp_function_chain->x_current_class_ptr = saved_class_ptr;
9916 cp_function_chain->x_current_class_ref = saved_class_ref;
9919 if (errorcount+sorrycount > errs
9920 && (complain & tf_warning_or_error))
9921 inform (input_location,
9922 " when instantiating default argument for call to %D", fn);
9924 /* Make sure the default argument is reasonable. */
9925 arg = check_default_argument (type, arg, complain);
9927 pop_access_scope (fn);
9932 /* Substitute into all the default arguments for FN. */
9935 tsubst_default_arguments (tree fn, tsubst_flags_t complain)
9940 tmpl_args = DECL_TI_ARGS (fn);
9942 /* If this function is not yet instantiated, we certainly don't need
9943 its default arguments. */
9944 if (uses_template_parms (tmpl_args))
9946 /* Don't do this again for clones. */
9947 if (DECL_CLONED_FUNCTION_P (fn))
9950 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
9952 arg = TREE_CHAIN (arg))
9953 if (TREE_PURPOSE (arg))
9954 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
9960 /* Substitute the ARGS into the T, which is a _DECL. Return the
9961 result of the substitution. Issue error and warning messages under
9962 control of COMPLAIN. */
9965 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
9967 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
9968 location_t saved_loc;
9973 /* Set the filename and linenumber to improve error-reporting. */
9974 saved_loc = input_location;
9975 input_location = DECL_SOURCE_LOCATION (t);
9977 switch (TREE_CODE (t))
9981 /* We can get here when processing a member function template,
9982 member class template, or template template parameter. */
9983 tree decl = DECL_TEMPLATE_RESULT (t);
9988 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
9990 /* Template template parameter is treated here. */
9991 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9992 if (new_type == error_mark_node)
9993 RETURN (error_mark_node);
9994 /* If we get a real template back, return it. This can happen in
9995 the context of most_specialized_class. */
9996 if (TREE_CODE (new_type) == TEMPLATE_DECL)
10000 DECL_CHAIN (r) = NULL_TREE;
10001 TREE_TYPE (r) = new_type;
10002 DECL_TEMPLATE_RESULT (r)
10003 = build_decl (DECL_SOURCE_LOCATION (decl),
10004 TYPE_DECL, DECL_NAME (decl), new_type);
10005 DECL_TEMPLATE_PARMS (r)
10006 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10008 TYPE_NAME (new_type) = r;
10012 /* We might already have an instance of this template.
10013 The ARGS are for the surrounding class type, so the
10014 full args contain the tsubst'd args for the context,
10015 plus the innermost args from the template decl. */
10016 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
10017 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
10018 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
10019 /* Because this is a template, the arguments will still be
10020 dependent, even after substitution. If
10021 PROCESSING_TEMPLATE_DECL is not set, the dependency
10022 predicates will short-circuit. */
10023 ++processing_template_decl;
10024 full_args = tsubst_template_args (tmpl_args, args,
10025 complain, in_decl);
10026 --processing_template_decl;
10027 if (full_args == error_mark_node)
10028 RETURN (error_mark_node);
10030 /* If this is a default template template argument,
10031 tsubst might not have changed anything. */
10032 if (full_args == tmpl_args)
10035 hash = hash_tmpl_and_args (t, full_args);
10036 spec = retrieve_specialization (t, full_args, hash);
10037 if (spec != NULL_TREE)
10043 /* Make a new template decl. It will be similar to the
10044 original, but will record the current template arguments.
10045 We also create a new function declaration, which is just
10046 like the old one, but points to this new template, rather
10047 than the old one. */
10049 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
10050 DECL_CHAIN (r) = NULL_TREE;
10052 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10054 if (TREE_CODE (decl) == TYPE_DECL
10055 && !TYPE_DECL_ALIAS_P (decl))
10058 ++processing_template_decl;
10059 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10060 --processing_template_decl;
10061 if (new_type == error_mark_node)
10062 RETURN (error_mark_node);
10064 TREE_TYPE (r) = new_type;
10065 CLASSTYPE_TI_TEMPLATE (new_type) = r;
10066 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
10067 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
10068 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
10073 ++processing_template_decl;
10074 new_decl = tsubst (decl, args, complain, in_decl);
10075 --processing_template_decl;
10076 if (new_decl == error_mark_node)
10077 RETURN (error_mark_node);
10079 DECL_TEMPLATE_RESULT (r) = new_decl;
10080 DECL_TI_TEMPLATE (new_decl) = r;
10081 TREE_TYPE (r) = TREE_TYPE (new_decl);
10082 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
10083 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
10086 SET_DECL_IMPLICIT_INSTANTIATION (r);
10087 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
10088 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
10090 /* The template parameters for this new template are all the
10091 template parameters for the old template, except the
10092 outermost level of parameters. */
10093 DECL_TEMPLATE_PARMS (r)
10094 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
10097 if (PRIMARY_TEMPLATE_P (t))
10098 DECL_PRIMARY_TEMPLATE (r) = r;
10100 if (TREE_CODE (decl) != TYPE_DECL)
10101 /* Record this non-type partial instantiation. */
10102 register_specialization (r, t,
10103 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
10108 case FUNCTION_DECL:
10111 tree argvec = NULL_TREE;
10119 /* Nobody should be tsubst'ing into non-template functions. */
10120 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
10122 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
10127 /* If T is not dependent, just return it. We have to
10128 increment PROCESSING_TEMPLATE_DECL because
10129 value_dependent_expression_p assumes that nothing is
10130 dependent when PROCESSING_TEMPLATE_DECL is zero. */
10131 ++processing_template_decl;
10132 dependent_p = value_dependent_expression_p (t);
10133 --processing_template_decl;
10137 /* Calculate the most general template of which R is a
10138 specialization, and the complete set of arguments used to
10140 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
10141 argvec = tsubst_template_args (DECL_TI_ARGS
10142 (DECL_TEMPLATE_RESULT
10143 (DECL_TI_TEMPLATE (t))),
10144 args, complain, in_decl);
10145 if (argvec == error_mark_node)
10146 RETURN (error_mark_node);
10148 /* Check to see if we already have this specialization. */
10149 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10150 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10158 /* We can see more levels of arguments than parameters if
10159 there was a specialization of a member template, like
10162 template <class T> struct S { template <class U> void f(); }
10163 template <> template <class U> void S<int>::f(U);
10165 Here, we'll be substituting into the specialization,
10166 because that's where we can find the code we actually
10167 want to generate, but we'll have enough arguments for
10168 the most general template.
10170 We also deal with the peculiar case:
10172 template <class T> struct S {
10173 template <class U> friend void f();
10175 template <class U> void f() {}
10177 template void f<double>();
10179 Here, the ARGS for the instantiation of will be {int,
10180 double}. But, we only need as many ARGS as there are
10181 levels of template parameters in CODE_PATTERN. We are
10182 careful not to get fooled into reducing the ARGS in
10185 template <class T> struct S { template <class U> void f(U); }
10186 template <class T> template <> void S<T>::f(int) {}
10188 which we can spot because the pattern will be a
10189 specialization in this case. */
10190 args_depth = TMPL_ARGS_DEPTH (args);
10192 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
10193 if (args_depth > parms_depth
10194 && !DECL_TEMPLATE_SPECIALIZATION (t))
10195 args = get_innermost_template_args (args, parms_depth);
10199 /* This special case arises when we have something like this:
10201 template <class T> struct S {
10202 friend void f<int>(int, double);
10205 Here, the DECL_TI_TEMPLATE for the friend declaration
10206 will be an IDENTIFIER_NODE. We are being called from
10207 tsubst_friend_function, and we want only to create a
10208 new decl (R) with appropriate types so that we can call
10209 determine_specialization. */
10210 gen_tmpl = NULL_TREE;
10213 if (DECL_CLASS_SCOPE_P (t))
10215 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
10219 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
10220 complain, t, /*entering_scope=*/1);
10225 ctx = DECL_CONTEXT (t);
10227 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10228 if (type == error_mark_node)
10229 RETURN (error_mark_node);
10231 /* If we hit excessive deduction depth, the type is bogus even if
10232 it isn't error_mark_node, so don't build a decl. */
10233 if (excessive_deduction_depth)
10234 RETURN (error_mark_node);
10236 /* We do NOT check for matching decls pushed separately at this
10237 point, as they may not represent instantiations of this
10238 template, and in any case are considered separate under the
10241 DECL_USE_TEMPLATE (r) = 0;
10242 TREE_TYPE (r) = type;
10243 /* Clear out the mangled name and RTL for the instantiation. */
10244 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10245 SET_DECL_RTL (r, NULL);
10246 /* Leave DECL_INITIAL set on deleted instantiations. */
10247 if (!DECL_DELETED_FN (r))
10248 DECL_INITIAL (r) = NULL_TREE;
10249 DECL_CONTEXT (r) = ctx;
10251 if (member && DECL_CONV_FN_P (r))
10252 /* Type-conversion operator. Reconstruct the name, in
10253 case it's the name of one of the template's parameters. */
10254 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
10256 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
10258 DECL_RESULT (r) = NULL_TREE;
10260 TREE_STATIC (r) = 0;
10261 TREE_PUBLIC (r) = TREE_PUBLIC (t);
10262 DECL_EXTERNAL (r) = 1;
10263 /* If this is an instantiation of a function with internal
10264 linkage, we already know what object file linkage will be
10265 assigned to the instantiation. */
10266 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
10267 DECL_DEFER_OUTPUT (r) = 0;
10268 DECL_CHAIN (r) = NULL_TREE;
10269 DECL_PENDING_INLINE_INFO (r) = 0;
10270 DECL_PENDING_INLINE_P (r) = 0;
10271 DECL_SAVED_TREE (r) = NULL_TREE;
10272 DECL_STRUCT_FUNCTION (r) = NULL;
10274 /* We'll re-clone as appropriate in instantiate_template. */
10275 DECL_CLONED_FUNCTION (r) = NULL_TREE;
10277 /* If we aren't complaining now, return on error before we register
10278 the specialization so that we'll complain eventually. */
10279 if ((complain & tf_error) == 0
10280 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10281 && !grok_op_properties (r, /*complain=*/false))
10282 RETURN (error_mark_node);
10284 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
10285 this in the special friend case mentioned above where
10286 GEN_TMPL is NULL. */
10289 DECL_TEMPLATE_INFO (r)
10290 = build_template_info (gen_tmpl, argvec);
10291 SET_DECL_IMPLICIT_INSTANTIATION (r);
10292 register_specialization (r, gen_tmpl, argvec, false, hash);
10294 /* We're not supposed to instantiate default arguments
10295 until they are called, for a template. But, for a
10298 template <class T> void f ()
10299 { extern void g(int i = T()); }
10301 we should do the substitution when the template is
10302 instantiated. We handle the member function case in
10303 instantiate_class_template since the default arguments
10304 might refer to other members of the class. */
10306 && !PRIMARY_TEMPLATE_P (gen_tmpl)
10307 && !uses_template_parms (argvec))
10308 tsubst_default_arguments (r, complain);
10311 DECL_TEMPLATE_INFO (r) = NULL_TREE;
10313 /* Copy the list of befriending classes. */
10314 for (friends = &DECL_BEFRIENDING_CLASSES (r);
10316 friends = &TREE_CHAIN (*friends))
10318 *friends = copy_node (*friends);
10319 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
10324 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
10326 maybe_retrofit_in_chrg (r);
10327 if (DECL_CONSTRUCTOR_P (r))
10328 grok_ctor_properties (ctx, r);
10329 if (DECL_INHERITED_CTOR_BASE (r))
10330 deduce_inheriting_ctor (r);
10331 /* If this is an instantiation of a member template, clone it.
10332 If it isn't, that'll be handled by
10333 clone_constructors_and_destructors. */
10334 if (PRIMARY_TEMPLATE_P (gen_tmpl))
10335 clone_function_decl (r, /*update_method_vec_p=*/0);
10337 else if ((complain & tf_error) != 0
10338 && IDENTIFIER_OPNAME_P (DECL_NAME (r))
10339 && !grok_op_properties (r, /*complain=*/true))
10340 RETURN (error_mark_node);
10342 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
10343 SET_DECL_FRIEND_CONTEXT (r,
10344 tsubst (DECL_FRIEND_CONTEXT (t),
10345 args, complain, in_decl));
10347 /* Possibly limit visibility based on template args. */
10348 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10349 if (DECL_VISIBILITY_SPECIFIED (t))
10351 DECL_VISIBILITY_SPECIFIED (r) = 0;
10352 DECL_ATTRIBUTES (r)
10353 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10355 determine_visibility (r);
10356 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r)
10357 && !processing_template_decl)
10358 defaulted_late_check (r);
10360 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10361 args, complain, in_decl);
10367 tree type = NULL_TREE;
10369 tree expanded_types = NULL_TREE;
10370 tree prev_r = NULL_TREE;
10371 tree first_r = NULL_TREE;
10373 if (FUNCTION_PARAMETER_PACK_P (t))
10375 /* If there is a local specialization that isn't a
10376 parameter pack, it means that we're doing a "simple"
10377 substitution from inside tsubst_pack_expansion. Just
10378 return the local specialization (which will be a single
10380 tree spec = retrieve_local_specialization (t);
10382 && TREE_CODE (spec) == PARM_DECL
10383 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
10386 /* Expand the TYPE_PACK_EXPANSION that provides the types for
10387 the parameters in this function parameter pack. */
10388 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
10389 complain, in_decl);
10390 if (TREE_CODE (expanded_types) == TREE_VEC)
10392 len = TREE_VEC_LENGTH (expanded_types);
10394 /* Zero-length parameter packs are boring. Just substitute
10397 RETURN (tsubst (TREE_CHAIN (t), args, complain,
10402 /* All we did was update the type. Make a note of that. */
10403 type = expanded_types;
10404 expanded_types = NULL_TREE;
10408 /* Loop through all of the parameter's we'll build. When T is
10409 a function parameter pack, LEN is the number of expanded
10410 types in EXPANDED_TYPES; otherwise, LEN is 1. */
10412 for (i = 0; i < len; ++i)
10416 if (DECL_TEMPLATE_PARM_P (t))
10417 SET_DECL_TEMPLATE_PARM_P (r);
10419 if (expanded_types)
10420 /* We're on the Ith parameter of the function parameter
10423 /* An argument of a function parameter pack is not a parameter
10425 FUNCTION_PARAMETER_PACK_P (r) = false;
10427 /* Get the Ith type. */
10428 type = TREE_VEC_ELT (expanded_types, i);
10430 /* Rename the parameter to include the index. */
10432 = make_ith_pack_parameter_name (DECL_NAME (r), i);
10435 /* We're dealing with a normal parameter. */
10436 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10438 type = type_decays_to (type);
10439 TREE_TYPE (r) = type;
10440 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10442 if (DECL_INITIAL (r))
10444 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
10445 DECL_INITIAL (r) = TREE_TYPE (r);
10447 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
10448 complain, in_decl);
10451 DECL_CONTEXT (r) = NULL_TREE;
10453 if (!DECL_TEMPLATE_PARM_P (r))
10454 DECL_ARG_TYPE (r) = type_passed_as (type);
10456 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10457 args, complain, in_decl);
10459 /* Keep track of the first new parameter we
10460 generate. That's what will be returned to the
10465 /* Build a proper chain of parameters when substituting
10466 into a function parameter pack. */
10468 DECL_CHAIN (prev_r) = r;
10471 /* If cp_unevaluated_operand is set, we're just looking for a
10472 single dummy parameter, so don't keep going. */
10473 if (DECL_CHAIN (t) && !cp_unevaluated_operand)
10474 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args,
10475 complain, DECL_CHAIN (t));
10477 /* FIRST_R contains the start of the chain we've built. */
10487 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10488 if (type == error_mark_node)
10489 RETURN (error_mark_node);
10490 TREE_TYPE (r) = type;
10491 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10493 if (DECL_C_BIT_FIELD (r))
10494 /* For bit-fields, DECL_INITIAL gives the number of bits. For
10495 non-bit-fields DECL_INITIAL is a non-static data member
10496 initializer, which gets deferred instantiation. */
10498 = tsubst_expr (DECL_INITIAL (t), args,
10500 /*integral_constant_expression_p=*/true);
10501 else if (DECL_INITIAL (t))
10503 /* Set up DECL_TEMPLATE_INFO so that we can get at the
10504 NSDMI in perform_member_init. Still set DECL_INITIAL
10505 so that we know there is one. */
10506 DECL_INITIAL (r) = void_zero_node;
10507 gcc_assert (DECL_LANG_SPECIFIC (r) == NULL);
10508 retrofit_lang_decl (r);
10509 DECL_TEMPLATE_INFO (r) = build_template_info (t, args);
10511 /* We don't have to set DECL_CONTEXT here; it is set by
10512 finish_member_declaration. */
10513 DECL_CHAIN (r) = NULL_TREE;
10514 if (VOID_TYPE_P (type))
10515 error ("instantiation of %q+D as type %qT", r, type);
10517 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
10518 args, complain, in_decl);
10523 /* We reach here only for member using decls. We also need to check
10524 uses_template_parms because DECL_DEPENDENT_P is not set for a
10525 using-declaration that designates a member of the current
10526 instantiation (c++/53549). */
10527 if (DECL_DEPENDENT_P (t)
10528 || uses_template_parms (USING_DECL_SCOPE (t)))
10530 tree inst_scope = tsubst_copy (USING_DECL_SCOPE (t), args,
10531 complain, in_decl);
10532 tree name = tsubst_copy (DECL_NAME (t), args, complain, in_decl);
10533 r = do_class_using_decl (inst_scope, name);
10535 r = error_mark_node;
10538 TREE_PROTECTED (r) = TREE_PROTECTED (t);
10539 TREE_PRIVATE (r) = TREE_PRIVATE (t);
10545 DECL_CHAIN (r) = NULL_TREE;
10552 tree argvec = NULL_TREE;
10553 tree gen_tmpl = NULL_TREE;
10555 tree tmpl = NULL_TREE;
10557 tree type = NULL_TREE;
10560 if (TREE_CODE (t) == TYPE_DECL
10561 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
10563 /* If this is the canonical decl, we don't have to
10564 mess with instantiations, and often we can't (for
10565 typename, template type parms and such). Note that
10566 TYPE_NAME is not correct for the above test if
10567 we've copied the type for a typedef. */
10568 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10569 if (type == error_mark_node)
10570 RETURN (error_mark_node);
10571 r = TYPE_NAME (type);
10575 /* Check to see if we already have the specialization we
10578 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
10580 /* T is a static data member or namespace-scope entity.
10581 We have to substitute into namespace-scope variables
10582 (even though such entities are never templates) because
10585 template <class T> void f() { extern T t; }
10587 where the entity referenced is not known until
10588 instantiation time. */
10590 ctx = DECL_CONTEXT (t);
10591 if (DECL_CLASS_SCOPE_P (t))
10593 ctx = tsubst_aggr_type (ctx, args,
10595 in_decl, /*entering_scope=*/1);
10596 /* If CTX is unchanged, then T is in fact the
10597 specialization we want. That situation occurs when
10598 referencing a static data member within in its own
10599 class. We can use pointer equality, rather than
10600 same_type_p, because DECL_CONTEXT is always
10602 if (ctx == DECL_CONTEXT (t)
10603 && (TREE_CODE (t) != TYPE_DECL
10604 /* ... unless T is a member template; in which
10605 case our caller can be willing to create a
10606 specialization of that template represented
10608 || !(DECL_TI_TEMPLATE (t)
10609 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (t)))))
10615 tmpl = DECL_TI_TEMPLATE (t);
10616 gen_tmpl = most_general_template (tmpl);
10617 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
10618 if (argvec == error_mark_node)
10619 RETURN (error_mark_node);
10620 hash = hash_tmpl_and_args (gen_tmpl, argvec);
10621 spec = retrieve_specialization (gen_tmpl, argvec, hash);
10626 /* A local variable. */
10628 /* Subsequent calls to pushdecl will fill this in. */
10630 spec = retrieve_local_specialization (t);
10632 /* If we already have the specialization we need, there is
10633 nothing more to do. */
10640 if (TREE_CODE (t) == VAR_DECL && DECL_ANON_UNION_VAR_P (t))
10642 /* Just use name lookup to find a member alias for an anonymous
10643 union, but then add it to the hash table. */
10644 r = lookup_name (DECL_NAME (t));
10645 gcc_assert (DECL_ANON_UNION_VAR_P (r));
10646 register_local_specialization (r, t);
10650 /* Create a new node for the specialization we need. */
10652 if (type == NULL_TREE)
10654 if (is_typedef_decl (t))
10655 type = DECL_ORIGINAL_TYPE (t);
10657 type = TREE_TYPE (t);
10658 if (TREE_CODE (t) == VAR_DECL
10659 && VAR_HAD_UNKNOWN_BOUND (t)
10660 && type != error_mark_node)
10661 type = strip_array_domain (type);
10662 type = tsubst (type, args, complain, in_decl);
10664 if (TREE_CODE (r) == VAR_DECL)
10666 /* Even if the original location is out of scope, the
10667 newly substituted one is not. */
10668 DECL_DEAD_FOR_LOCAL (r) = 0;
10669 DECL_INITIALIZED_P (r) = 0;
10670 DECL_TEMPLATE_INSTANTIATED (r) = 0;
10671 if (type == error_mark_node)
10672 RETURN (error_mark_node);
10673 if (TREE_CODE (type) == FUNCTION_TYPE)
10675 /* It may seem that this case cannot occur, since:
10680 declares a function, not a variable. However:
10683 template <typename T> void g() { T t; }
10684 template void g<f>();
10686 is an attempt to declare a variable with function
10688 error ("variable %qD has function type",
10689 /* R is not yet sufficiently initialized, so we
10690 just use its name. */
10692 RETURN (error_mark_node);
10694 type = complete_type (type);
10695 /* Wait until cp_finish_decl to set this again, to handle
10696 circular dependency (template/instantiate6.C). */
10697 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0;
10698 type = check_var_type (DECL_NAME (r), type);
10700 if (DECL_HAS_VALUE_EXPR_P (t))
10702 tree ve = DECL_VALUE_EXPR (t);
10703 ve = tsubst_expr (ve, args, complain, in_decl,
10704 /*constant_expression_p=*/false);
10705 if (REFERENCE_REF_P (ve))
10707 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
10708 ve = TREE_OPERAND (ve, 0);
10710 SET_DECL_VALUE_EXPR (r, ve);
10713 else if (DECL_SELF_REFERENCE_P (t))
10714 SET_DECL_SELF_REFERENCE_P (r);
10715 TREE_TYPE (r) = type;
10716 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
10717 DECL_CONTEXT (r) = ctx;
10718 /* Clear out the mangled name and RTL for the instantiation. */
10719 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
10720 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10721 SET_DECL_RTL (r, NULL);
10722 /* The initializer must not be expanded until it is required;
10723 see [temp.inst]. */
10724 DECL_INITIAL (r) = NULL_TREE;
10725 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
10726 SET_DECL_RTL (r, NULL);
10727 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
10728 if (TREE_CODE (r) == VAR_DECL)
10730 /* Possibly limit visibility based on template args. */
10731 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
10732 if (DECL_VISIBILITY_SPECIFIED (t))
10734 DECL_VISIBILITY_SPECIFIED (r) = 0;
10735 DECL_ATTRIBUTES (r)
10736 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
10738 determine_visibility (r);
10743 /* A static data member declaration is always marked
10744 external when it is declared in-class, even if an
10745 initializer is present. We mimic the non-template
10746 processing here. */
10747 DECL_EXTERNAL (r) = 1;
10749 register_specialization (r, gen_tmpl, argvec, false, hash);
10750 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec);
10751 SET_DECL_IMPLICIT_INSTANTIATION (r);
10753 else if (cp_unevaluated_operand)
10755 /* We're substituting this var in a decltype outside of its
10756 scope, such as for a lambda return type. Don't add it to
10757 local_specializations, do perform auto deduction. */
10758 tree auto_node = type_uses_auto (type);
10762 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl,
10763 /*constant_expression_p=*/false);
10764 init = resolve_nondeduced_context (init);
10765 TREE_TYPE (r) = type
10766 = do_auto_deduction (type, init, auto_node);
10770 register_local_specialization (r, t);
10772 DECL_CHAIN (r) = NULL_TREE;
10774 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
10776 args, complain, in_decl);
10778 /* Preserve a typedef that names a type. */
10779 if (is_typedef_decl (r))
10781 DECL_ORIGINAL_TYPE (r) = NULL_TREE;
10782 set_underlying_type (r);
10785 layout_decl (r, 0);
10790 gcc_unreachable ();
10795 /* Restore the file and line information. */
10796 input_location = saved_loc;
10801 /* Substitute into the ARG_TYPES of a function type.
10802 If END is a TREE_CHAIN, leave it and any following types
10806 tsubst_arg_types (tree arg_types,
10809 tsubst_flags_t complain,
10812 tree remaining_arg_types;
10813 tree type = NULL_TREE;
10815 tree expanded_args = NULL_TREE;
10818 if (!arg_types || arg_types == void_list_node || arg_types == end)
10821 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
10822 args, end, complain, in_decl);
10823 if (remaining_arg_types == error_mark_node)
10824 return error_mark_node;
10826 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
10828 /* For a pack expansion, perform substitution on the
10829 entire expression. Later on, we'll handle the arguments
10831 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
10832 args, complain, in_decl);
10834 if (TREE_CODE (expanded_args) == TREE_VEC)
10835 /* So that we'll spin through the parameters, one by one. */
10836 i = TREE_VEC_LENGTH (expanded_args);
10839 /* We only partially substituted into the parameter
10840 pack. Our type is TYPE_PACK_EXPANSION. */
10841 type = expanded_args;
10842 expanded_args = NULL_TREE;
10850 type = TREE_VEC_ELT (expanded_args, i);
10852 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
10854 if (type == error_mark_node)
10855 return error_mark_node;
10856 if (VOID_TYPE_P (type))
10858 if (complain & tf_error)
10860 error ("invalid parameter type %qT", type);
10862 error ("in declaration %q+D", in_decl);
10864 return error_mark_node;
10867 if (abstract_virtuals_error_sfinae (NULL_TREE, type, complain))
10868 return error_mark_node;
10870 /* Do array-to-pointer, function-to-pointer conversion, and ignore
10871 top-level qualifiers as required. */
10872 type = cv_unqualified (type_decays_to (type));
10874 /* We do not substitute into default arguments here. The standard
10875 mandates that they be instantiated only when needed, which is
10876 done in build_over_call. */
10877 default_arg = TREE_PURPOSE (arg_types);
10879 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
10881 /* We've instantiated a template before its default arguments
10882 have been parsed. This can happen for a nested template
10883 class, and is not an error unless we require the default
10884 argument in a call of this function. */
10885 remaining_arg_types =
10886 tree_cons (default_arg, type, remaining_arg_types);
10887 vec_safe_push (DEFARG_INSTANTIATIONS(default_arg), remaining_arg_types);
10890 remaining_arg_types =
10891 hash_tree_cons (default_arg, type, remaining_arg_types);
10894 return remaining_arg_types;
10897 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
10898 *not* handle the exception-specification for FNTYPE, because the
10899 initial substitution of explicitly provided template parameters
10900 during argument deduction forbids substitution into the
10901 exception-specification:
10905 All references in the function type of the function template to the
10906 corresponding template parameters are replaced by the specified tem-
10907 plate argument values. If a substitution in a template parameter or
10908 in the function type of the function template results in an invalid
10909 type, type deduction fails. [Note: The equivalent substitution in
10910 exception specifications is done only when the function is instanti-
10911 ated, at which point a program is ill-formed if the substitution
10912 results in an invalid type.] */
10915 tsubst_function_type (tree t,
10917 tsubst_flags_t complain,
10924 /* The TYPE_CONTEXT is not used for function/method types. */
10925 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
10927 /* Substitute the return type. */
10928 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10929 if (return_type == error_mark_node)
10930 return error_mark_node;
10931 /* DR 486 clarifies that creation of a function type with an
10932 invalid return type is a deduction failure. */
10933 if (TREE_CODE (return_type) == ARRAY_TYPE
10934 || TREE_CODE (return_type) == FUNCTION_TYPE)
10936 if (complain & tf_error)
10938 if (TREE_CODE (return_type) == ARRAY_TYPE)
10939 error ("function returning an array");
10941 error ("function returning a function");
10943 return error_mark_node;
10946 if (abstract_virtuals_error_sfinae (NULL_TREE, return_type, complain))
10947 return error_mark_node;
10949 /* Substitute the argument types. */
10950 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args, NULL_TREE,
10951 complain, in_decl);
10952 if (arg_types == error_mark_node)
10953 return error_mark_node;
10955 /* Construct a new type node and return it. */
10956 if (TREE_CODE (t) == FUNCTION_TYPE)
10958 fntype = build_function_type (return_type, arg_types);
10959 fntype = apply_memfn_quals (fntype,
10960 type_memfn_quals (t),
10961 type_memfn_rqual (t));
10965 tree r = TREE_TYPE (TREE_VALUE (arg_types));
10966 if (! MAYBE_CLASS_TYPE_P (r))
10970 Type deduction may fail for any of the following
10973 -- Attempting to create "pointer to member of T" when T
10974 is not a class type. */
10975 if (complain & tf_error)
10976 error ("creating pointer to member function of non-class type %qT",
10978 return error_mark_node;
10981 fntype = build_method_type_directly (r, return_type,
10982 TREE_CHAIN (arg_types));
10983 fntype = build_ref_qualified_type (fntype, type_memfn_rqual (t));
10985 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
10990 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
10991 ARGS into that specification, and return the substituted
10992 specification. If there is no specification, return NULL_TREE. */
10995 tsubst_exception_specification (tree fntype,
10997 tsubst_flags_t complain,
11004 specs = TYPE_RAISES_EXCEPTIONS (fntype);
11005 new_specs = NULL_TREE;
11006 if (specs && TREE_PURPOSE (specs))
11008 /* A noexcept-specifier. */
11009 tree expr = TREE_PURPOSE (specs);
11010 if (TREE_CODE (expr) == INTEGER_CST)
11014 /* Defer instantiation of noexcept-specifiers to avoid
11015 excessive instantiations (c++/49107). */
11016 new_specs = make_node (DEFERRED_NOEXCEPT);
11017 if (DEFERRED_NOEXCEPT_SPEC_P (specs))
11019 /* We already partially instantiated this member template,
11020 so combine the new args with the old. */
11021 DEFERRED_NOEXCEPT_PATTERN (new_specs)
11022 = DEFERRED_NOEXCEPT_PATTERN (expr);
11023 DEFERRED_NOEXCEPT_ARGS (new_specs)
11024 = add_to_template_args (DEFERRED_NOEXCEPT_ARGS (expr), args);
11028 DEFERRED_NOEXCEPT_PATTERN (new_specs) = expr;
11029 DEFERRED_NOEXCEPT_ARGS (new_specs) = args;
11033 new_specs = tsubst_copy_and_build
11034 (expr, args, complain, in_decl, /*function_p=*/false,
11035 /*integral_constant_expression_p=*/true);
11036 new_specs = build_noexcept_spec (new_specs, complain);
11040 if (! TREE_VALUE (specs))
11047 tree expanded_specs = NULL_TREE;
11049 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
11051 /* Expand the pack expansion type. */
11052 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
11056 if (expanded_specs == error_mark_node)
11057 return error_mark_node;
11058 else if (TREE_CODE (expanded_specs) == TREE_VEC)
11059 len = TREE_VEC_LENGTH (expanded_specs);
11062 /* We're substituting into a member template, so
11063 we got a TYPE_PACK_EXPANSION back. Add that
11064 expansion and move on. */
11065 gcc_assert (TREE_CODE (expanded_specs)
11066 == TYPE_PACK_EXPANSION);
11067 new_specs = add_exception_specifier (new_specs,
11070 specs = TREE_CHAIN (specs);
11075 for (i = 0; i < len; ++i)
11077 if (expanded_specs)
11078 spec = TREE_VEC_ELT (expanded_specs, i);
11080 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
11081 if (spec == error_mark_node)
11083 new_specs = add_exception_specifier (new_specs, spec,
11087 specs = TREE_CHAIN (specs);
11093 /* Take the tree structure T and replace template parameters used
11094 therein with the argument vector ARGS. IN_DECL is an associated
11095 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
11096 Issue error and warning messages under control of COMPLAIN. Note
11097 that we must be relatively non-tolerant of extensions here, in
11098 order to preserve conformance; if we allow substitutions that
11099 should not be allowed, we may allow argument deductions that should
11100 not succeed, and therefore report ambiguous overload situations
11101 where there are none. In theory, we could allow the substitution,
11102 but indicate that it should have failed, and allow our caller to
11103 make sure that the right thing happens, but we don't try to do this
11106 This function is used for dealing with types, decls and the like;
11107 for expressions, use tsubst_expr or tsubst_copy. */
11110 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
11112 enum tree_code code;
11113 tree type, r = NULL_TREE;
11115 if (t == NULL_TREE || t == error_mark_node
11116 || t == integer_type_node
11117 || t == void_type_node
11118 || t == char_type_node
11119 || t == unknown_type_node
11120 || TREE_CODE (t) == NAMESPACE_DECL
11121 || TREE_CODE (t) == TRANSLATION_UNIT_DECL)
11125 return tsubst_decl (t, args, complain);
11127 if (args == NULL_TREE)
11130 code = TREE_CODE (t);
11132 if (code == IDENTIFIER_NODE)
11133 type = IDENTIFIER_TYPE_VALUE (t);
11135 type = TREE_TYPE (t);
11137 gcc_assert (type != unknown_type_node);
11139 /* Reuse typedefs. We need to do this to handle dependent attributes,
11140 such as attribute aligned. */
11142 && typedef_variant_p (t))
11144 tree decl = TYPE_NAME (t);
11146 if (alias_template_specialization_p (t))
11148 /* DECL represents an alias template and we want to
11150 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11151 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
11152 r = instantiate_alias_template (tmpl, gen_args, complain);
11154 else if (DECL_CLASS_SCOPE_P (decl)
11155 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
11156 && uses_template_parms (DECL_CONTEXT (decl)))
11158 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11159 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
11160 r = retrieve_specialization (tmpl, gen_args, 0);
11162 else if (DECL_FUNCTION_SCOPE_P (decl)
11163 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
11164 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
11165 r = retrieve_local_specialization (decl);
11167 /* The typedef is from a non-template context. */
11173 r = cp_build_qualified_type_real
11174 (r, cp_type_quals (t) | cp_type_quals (r),
11175 complain | tf_ignore_bad_quals);
11180 /* We don't have an instantiation yet, so drop the typedef. */
11181 int quals = cp_type_quals (t);
11182 t = DECL_ORIGINAL_TYPE (decl);
11183 t = cp_build_qualified_type_real (t, quals,
11184 complain | tf_ignore_bad_quals);
11189 && code != TYPENAME_TYPE
11190 && code != TEMPLATE_TYPE_PARM
11191 && code != IDENTIFIER_NODE
11192 && code != FUNCTION_TYPE
11193 && code != METHOD_TYPE)
11194 type = tsubst (type, args, complain, in_decl);
11195 if (type == error_mark_node)
11196 return error_mark_node;
11202 case ENUMERAL_TYPE:
11203 return tsubst_aggr_type (t, args, complain, in_decl,
11204 /*entering_scope=*/0);
11207 case IDENTIFIER_NODE:
11218 if (t == integer_type_node)
11221 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
11222 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
11226 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
11228 max = tsubst_expr (omax, args, complain, in_decl,
11229 /*integral_constant_expression_p=*/false);
11231 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
11233 if (TREE_CODE (max) == NOP_EXPR
11234 && TREE_SIDE_EFFECTS (omax)
11235 && !TREE_TYPE (max))
11236 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
11238 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
11239 with TREE_SIDE_EFFECTS that indicates this is not an integral
11240 constant expression. */
11241 if (processing_template_decl
11242 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
11244 gcc_assert (TREE_CODE (max) == NOP_EXPR);
11245 TREE_SIDE_EFFECTS (max) = 1;
11248 return compute_array_index_type (NULL_TREE, max, complain);
11251 case TEMPLATE_TYPE_PARM:
11252 case TEMPLATE_TEMPLATE_PARM:
11253 case BOUND_TEMPLATE_TEMPLATE_PARM:
11254 case TEMPLATE_PARM_INDEX:
11259 tree arg = NULL_TREE;
11263 gcc_assert (TREE_VEC_LENGTH (args) > 0);
11264 template_parm_level_and_index (t, &level, &idx);
11266 levels = TMPL_ARGS_DEPTH (args);
11267 if (level <= levels)
11269 arg = TMPL_ARG (args, level, idx);
11271 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
11273 /* See through ARGUMENT_PACK_SELECT arguments. */
11274 arg = ARGUMENT_PACK_SELECT_ARG (arg);
11275 /* If the selected argument is an expansion E, that most
11276 likely means we were called from
11277 gen_elem_of_pack_expansion_instantiation during the
11278 substituting of pack an argument pack (which Ith
11279 element is a pack expansion, where I is
11280 ARGUMENT_PACK_SELECT_INDEX) into a pack expansion.
11281 In this case, the Ith element resulting from this
11282 substituting is going to be a pack expansion, which
11283 pattern is the pattern of E. Let's return the
11285 gen_elem_of_pack_expansion_instantiation will
11286 build the resulting pack expansion from it. */
11287 if (PACK_EXPANSION_P (arg))
11288 arg = PACK_EXPANSION_PATTERN (arg);
11292 if (arg == error_mark_node)
11293 return error_mark_node;
11294 else if (arg != NULL_TREE)
11296 if (ARGUMENT_PACK_P (arg))
11297 /* If ARG is an argument pack, we don't actually want to
11298 perform a substitution here, because substitutions
11299 for argument packs are only done
11300 element-by-element. We can get to this point when
11301 substituting the type of a non-type template
11302 parameter pack, when that type actually contains
11303 template parameter packs from an outer template, e.g.,
11305 template<typename... Types> struct A {
11306 template<Types... Values> struct B { };
11310 if (code == TEMPLATE_TYPE_PARM)
11313 gcc_assert (TYPE_P (arg));
11315 quals = cp_type_quals (arg) | cp_type_quals (t);
11317 return cp_build_qualified_type_real
11318 (arg, quals, complain | tf_ignore_bad_quals);
11320 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11322 /* We are processing a type constructed from a
11323 template template parameter. */
11324 tree argvec = tsubst (TYPE_TI_ARGS (t),
11325 args, complain, in_decl);
11326 if (argvec == error_mark_node)
11327 return error_mark_node;
11329 gcc_assert (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
11330 || TREE_CODE (arg) == TEMPLATE_DECL
11331 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
11333 if (TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE)
11334 /* Consider this code:
11336 template <template <class> class Template>
11338 template <class Arg> using Bind = Template<Arg>;
11341 template <template <class> class Template, class Arg>
11342 using Instantiate = Template<Arg>; //#0
11344 template <template <class> class Template,
11347 Instantiate<Internal<Template>::template Bind,
11350 When #1 is parsed, the
11351 BOUND_TEMPLATE_TEMPLATE_PARM representing the
11352 parameter `Template' in #0 matches the
11353 UNBOUND_CLASS_TEMPLATE representing the argument
11354 `Internal<Template>::template Bind'; We then want
11355 to assemble the type `Bind<Argument>' that can't
11356 be fully created right now, because
11357 `Internal<Template>' not being complete, the Bind
11358 template cannot be looked up in that context. So
11359 we need to "store" `Bind<Argument>' for later
11360 when the context of Bind becomes complete. Let's
11361 store that in a TYPENAME_TYPE. */
11362 return make_typename_type (TYPE_CONTEXT (arg),
11363 build_nt (TEMPLATE_ID_EXPR,
11364 TYPE_IDENTIFIER (arg),
11369 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
11370 are resolving nested-types in the signature of a
11371 member function templates. Otherwise ARG is a
11372 TEMPLATE_DECL and is the real template to be
11374 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
11375 arg = TYPE_NAME (arg);
11377 r = lookup_template_class (arg,
11379 DECL_CONTEXT (arg),
11380 /*entering_scope=*/0,
11382 return cp_build_qualified_type_real
11383 (r, cp_type_quals (t), complain);
11386 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
11387 return convert_from_reference (unshare_expr (arg));
11391 /* This can happen during the attempted tsubst'ing in
11392 unify. This means that we don't yet have any information
11393 about the template parameter in question. */
11396 /* Early in template argument deduction substitution, we don't
11397 want to reduce the level of 'auto', or it will be confused
11398 with a normal template parm in subsequent deduction. */
11399 if (is_auto (t) && (complain & tf_partial))
11402 /* If we get here, we must have been looking at a parm for a
11403 more deeply nested template. Make a new version of this
11404 template parameter, but with a lower level. */
11407 case TEMPLATE_TYPE_PARM:
11408 case TEMPLATE_TEMPLATE_PARM:
11409 case BOUND_TEMPLATE_TEMPLATE_PARM:
11410 if (cp_type_quals (t))
11412 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
11413 r = cp_build_qualified_type_real
11414 (r, cp_type_quals (t),
11415 complain | (code == TEMPLATE_TYPE_PARM
11416 ? tf_ignore_bad_quals : 0));
11421 TEMPLATE_TYPE_PARM_INDEX (r)
11422 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
11423 r, levels, args, complain);
11424 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
11425 TYPE_MAIN_VARIANT (r) = r;
11426 TYPE_POINTER_TO (r) = NULL_TREE;
11427 TYPE_REFERENCE_TO (r) = NULL_TREE;
11429 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
11430 /* We have reduced the level of the template
11431 template parameter, but not the levels of its
11432 template parameters, so canonical_type_parameter
11433 will not be able to find the canonical template
11434 template parameter for this level. Thus, we
11435 require structural equality checking to compare
11436 TEMPLATE_TEMPLATE_PARMs. */
11437 SET_TYPE_STRUCTURAL_EQUALITY (r);
11438 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
11439 SET_TYPE_STRUCTURAL_EQUALITY (r);
11441 TYPE_CANONICAL (r) = canonical_type_parameter (r);
11443 if (code == BOUND_TEMPLATE_TEMPLATE_PARM)
11445 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
11446 complain, in_decl);
11447 if (argvec == error_mark_node)
11448 return error_mark_node;
11450 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
11451 = build_template_info (TYPE_TI_TEMPLATE (t), argvec);
11456 case TEMPLATE_PARM_INDEX:
11457 r = reduce_template_parm_level (t, type, levels, args, complain);
11461 gcc_unreachable ();
11469 tree purpose, value, chain;
11471 if (t == void_list_node)
11474 purpose = TREE_PURPOSE (t);
11477 purpose = tsubst (purpose, args, complain, in_decl);
11478 if (purpose == error_mark_node)
11479 return error_mark_node;
11481 value = TREE_VALUE (t);
11484 value = tsubst (value, args, complain, in_decl);
11485 if (value == error_mark_node)
11486 return error_mark_node;
11488 chain = TREE_CHAIN (t);
11489 if (chain && chain != void_type_node)
11491 chain = tsubst (chain, args, complain, in_decl);
11492 if (chain == error_mark_node)
11493 return error_mark_node;
11495 if (purpose == TREE_PURPOSE (t)
11496 && value == TREE_VALUE (t)
11497 && chain == TREE_CHAIN (t))
11499 return hash_tree_cons (purpose, value, chain);
11503 /* We should never be tsubsting a binfo. */
11504 gcc_unreachable ();
11507 /* A vector of template arguments. */
11508 gcc_assert (!type);
11509 return tsubst_template_args (t, args, complain, in_decl);
11512 case REFERENCE_TYPE:
11514 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
11519 Type deduction may fail for any of the following
11522 -- Attempting to create a pointer to reference type.
11523 -- Attempting to create a reference to a reference type or
11524 a reference to void.
11526 Core issue 106 says that creating a reference to a reference
11527 during instantiation is no longer a cause for failure. We
11528 only enforce this check in strict C++98 mode. */
11529 if ((TREE_CODE (type) == REFERENCE_TYPE
11530 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
11531 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
11533 static location_t last_loc;
11535 /* We keep track of the last time we issued this error
11536 message to avoid spewing a ton of messages during a
11537 single bad template instantiation. */
11538 if (complain & tf_error
11539 && last_loc != input_location)
11541 if (TREE_CODE (type) == VOID_TYPE)
11542 error ("forming reference to void");
11543 else if (code == POINTER_TYPE)
11544 error ("forming pointer to reference type %qT", type);
11546 error ("forming reference to reference type %qT", type);
11547 last_loc = input_location;
11550 return error_mark_node;
11552 else if (code == POINTER_TYPE)
11554 r = build_pointer_type (type);
11555 if (TREE_CODE (type) == METHOD_TYPE)
11556 r = build_ptrmemfunc_type (r);
11558 else if (TREE_CODE (type) == REFERENCE_TYPE)
11559 /* In C++0x, during template argument substitution, when there is an
11560 attempt to create a reference to a reference type, reference
11561 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
11563 "If a template-argument for a template-parameter T names a type
11564 that is a reference to a type A, an attempt to create the type
11565 'lvalue reference to cv T' creates the type 'lvalue reference to
11566 A,' while an attempt to create the type type rvalue reference to
11567 cv T' creates the type T"
11569 r = cp_build_reference_type
11571 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
11573 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
11574 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain);
11576 if (r != error_mark_node)
11577 /* Will this ever be needed for TYPE_..._TO values? */
11584 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
11585 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
11589 Type deduction may fail for any of the following
11592 -- Attempting to create "pointer to member of T" when T
11593 is not a class type. */
11594 if (complain & tf_error)
11595 error ("creating pointer to member of non-class type %qT", r);
11596 return error_mark_node;
11598 if (TREE_CODE (type) == REFERENCE_TYPE)
11600 if (complain & tf_error)
11601 error ("creating pointer to member reference type %qT", type);
11602 return error_mark_node;
11604 if (TREE_CODE (type) == VOID_TYPE)
11606 if (complain & tf_error)
11607 error ("creating pointer to member of type void");
11608 return error_mark_node;
11610 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
11611 if (TREE_CODE (type) == FUNCTION_TYPE)
11613 /* The type of the implicit object parameter gets its
11614 cv-qualifiers from the FUNCTION_TYPE. */
11617 = build_memfn_type (type, r, type_memfn_quals (type),
11618 type_memfn_rqual (type));
11619 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
11620 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
11624 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
11628 case FUNCTION_TYPE:
11633 fntype = tsubst_function_type (t, args, complain, in_decl);
11634 if (fntype == error_mark_node)
11635 return error_mark_node;
11637 /* Substitute the exception specification. */
11638 specs = tsubst_exception_specification (t, args, complain,
11639 in_decl, /*defer_ok*/true);
11640 if (specs == error_mark_node)
11641 return error_mark_node;
11643 fntype = build_exception_variant (fntype, specs);
11648 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
11649 if (domain == error_mark_node)
11650 return error_mark_node;
11652 /* As an optimization, we avoid regenerating the array type if
11653 it will obviously be the same as T. */
11654 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
11657 /* These checks should match the ones in grokdeclarator.
11661 The deduction may fail for any of the following reasons:
11663 -- Attempting to create an array with an element type that
11664 is void, a function type, or a reference type, or [DR337]
11665 an abstract class type. */
11666 if (TREE_CODE (type) == VOID_TYPE
11667 || TREE_CODE (type) == FUNCTION_TYPE
11668 || TREE_CODE (type) == REFERENCE_TYPE)
11670 if (complain & tf_error)
11671 error ("creating array of %qT", type);
11672 return error_mark_node;
11674 if (ABSTRACT_CLASS_TYPE_P (type))
11676 if (complain & tf_error)
11677 error ("creating array of %qT, which is an abstract class type",
11679 return error_mark_node;
11682 r = build_cplus_array_type (type, domain);
11684 if (TYPE_USER_ALIGN (t))
11686 TYPE_ALIGN (r) = TYPE_ALIGN (t);
11687 TYPE_USER_ALIGN (r) = 1;
11693 case TYPENAME_TYPE:
11695 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11696 in_decl, /*entering_scope=*/1);
11697 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
11698 complain, in_decl);
11700 if (ctx == error_mark_node || f == error_mark_node)
11701 return error_mark_node;
11703 if (!MAYBE_CLASS_TYPE_P (ctx))
11705 if (complain & tf_error)
11706 error ("%qT is not a class, struct, or union type", ctx);
11707 return error_mark_node;
11709 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
11711 /* Normally, make_typename_type does not require that the CTX
11712 have complete type in order to allow things like:
11714 template <class T> struct S { typename S<T>::X Y; };
11716 But, such constructs have already been resolved by this
11717 point, so here CTX really should have complete type, unless
11718 it's a partial instantiation. */
11719 ctx = complete_type (ctx);
11720 if (!COMPLETE_TYPE_P (ctx))
11722 if (complain & tf_error)
11723 cxx_incomplete_type_error (NULL_TREE, ctx);
11724 return error_mark_node;
11728 f = make_typename_type (ctx, f, typename_type,
11729 complain | tf_keep_type_decl);
11730 if (f == error_mark_node)
11732 if (TREE_CODE (f) == TYPE_DECL)
11734 complain |= tf_ignore_bad_quals;
11738 if (TREE_CODE (f) != TYPENAME_TYPE)
11740 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
11742 if (complain & tf_error)
11743 error ("%qT resolves to %qT, which is not an enumeration type",
11746 return error_mark_node;
11748 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
11750 if (complain & tf_error)
11751 error ("%qT resolves to %qT, which is is not a class type",
11754 return error_mark_node;
11758 return cp_build_qualified_type_real
11759 (f, cp_type_quals (f) | cp_type_quals (t), complain);
11762 case UNBOUND_CLASS_TEMPLATE:
11764 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
11765 in_decl, /*entering_scope=*/1);
11766 tree name = TYPE_IDENTIFIER (t);
11767 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
11769 if (ctx == error_mark_node || name == error_mark_node)
11770 return error_mark_node;
11773 parm_list = tsubst_template_parms (parm_list, args, complain);
11774 return make_unbound_class_template (ctx, name, parm_list, complain);
11781 ++cp_unevaluated_operand;
11782 ++c_inhibit_evaluation_warnings;
11784 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
11786 /*integral_constant_expression_p=*/false);
11788 --cp_unevaluated_operand;
11789 --c_inhibit_evaluation_warnings;
11791 type = finish_typeof (type);
11792 return cp_build_qualified_type_real (type,
11794 | cp_type_quals (type),
11798 case DECLTYPE_TYPE:
11802 ++cp_unevaluated_operand;
11803 ++c_inhibit_evaluation_warnings;
11805 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
11806 complain|tf_decltype, in_decl,
11807 /*integral_constant_expression_p=*/false);
11809 --cp_unevaluated_operand;
11810 --c_inhibit_evaluation_warnings;
11812 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t))
11813 type = lambda_capture_field_type (type);
11814 else if (DECLTYPE_FOR_LAMBDA_PROXY (t))
11815 type = lambda_proxy_type (type);
11818 bool id = DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t);
11819 if (id && TREE_CODE (DECLTYPE_TYPE_EXPR (t)) == BIT_NOT_EXPR
11821 /* In a template ~id could be either a complement expression
11822 or an unqualified-id naming a destructor; if instantiating
11823 it produces an expression, it's not an id-expression or
11826 type = finish_decltype_type (type, id, complain);
11828 return cp_build_qualified_type_real (type,
11830 | cp_type_quals (type),
11834 case UNDERLYING_TYPE:
11836 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args,
11837 complain, in_decl);
11838 return finish_underlying_type (type);
11841 case TYPE_ARGUMENT_PACK:
11842 case NONTYPE_ARGUMENT_PACK:
11844 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code);
11846 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
11850 SET_ARGUMENT_PACK_ARGS (r, packed_out);
11852 /* For template nontype argument packs, also substitute into
11854 if (code == NONTYPE_ARGUMENT_PACK)
11855 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
11873 /* We should use one of the expression tsubsts for these codes. */
11874 gcc_unreachable ();
11877 sorry ("use of %qs in template", tree_code_name [(int) code]);
11878 return error_mark_node;
11882 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
11883 type of the expression on the left-hand side of the "." or "->"
11887 tsubst_baselink (tree baselink, tree object_type,
11888 tree args, tsubst_flags_t complain, tree in_decl)
11891 tree qualifying_scope;
11894 tree template_args = 0;
11895 bool template_id_p = false;
11896 bool qualified = BASELINK_QUALIFIED_P (baselink);
11898 /* A baselink indicates a function from a base class. Both the
11899 BASELINK_ACCESS_BINFO and the base class referenced may
11900 indicate bases of the template class, rather than the
11901 instantiated class. In addition, lookups that were not
11902 ambiguous before may be ambiguous now. Therefore, we perform
11903 the lookup again. */
11904 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
11905 qualifying_scope = tsubst (qualifying_scope, args,
11906 complain, in_decl);
11907 fns = BASELINK_FUNCTIONS (baselink);
11908 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl);
11909 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
11911 template_id_p = true;
11912 template_args = TREE_OPERAND (fns, 1);
11913 fns = TREE_OPERAND (fns, 0);
11915 template_args = tsubst_template_args (template_args, args,
11916 complain, in_decl);
11918 name = DECL_NAME (get_first_fn (fns));
11919 if (IDENTIFIER_TYPENAME_P (name))
11920 name = mangle_conv_op_name_for_type (optype);
11921 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
11923 return error_mark_node;
11925 /* If lookup found a single function, mark it as used at this
11926 point. (If it lookup found multiple functions the one selected
11927 later by overload resolution will be marked as used at that
11929 if (BASELINK_P (baselink))
11930 fns = BASELINK_FUNCTIONS (baselink);
11931 if (!template_id_p && !really_overloaded_fn (fns))
11932 mark_used (OVL_CURRENT (fns));
11934 /* Add back the template arguments, if present. */
11935 if (BASELINK_P (baselink) && template_id_p)
11936 BASELINK_FUNCTIONS (baselink)
11937 = build_nt (TEMPLATE_ID_EXPR,
11938 BASELINK_FUNCTIONS (baselink),
11940 /* Update the conversion operator type. */
11941 BASELINK_OPTYPE (baselink) = optype;
11944 object_type = current_class_type;
11947 baselink = adjust_result_of_qualified_name_lookup (baselink,
11953 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
11954 true if the qualified-id will be a postfix-expression in-and-of
11955 itself; false if more of the postfix-expression follows the
11956 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
11960 tsubst_qualified_id (tree qualified_id, tree args,
11961 tsubst_flags_t complain, tree in_decl,
11962 bool done, bool address_p)
11968 tree template_args;
11969 location_t loc = UNKNOWN_LOCATION;
11971 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
11973 /* Figure out what name to look up. */
11974 name = TREE_OPERAND (qualified_id, 1);
11975 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
11977 is_template = true;
11978 loc = EXPR_LOCATION (name);
11979 template_args = TREE_OPERAND (name, 1);
11981 template_args = tsubst_template_args (template_args, args,
11982 complain, in_decl);
11983 name = TREE_OPERAND (name, 0);
11987 is_template = false;
11988 template_args = NULL_TREE;
11991 /* Substitute into the qualifying scope. When there are no ARGS, we
11992 are just trying to simplify a non-dependent expression. In that
11993 case the qualifying scope may be dependent, and, in any case,
11994 substituting will not help. */
11995 scope = TREE_OPERAND (qualified_id, 0);
11998 scope = tsubst (scope, args, complain, in_decl);
11999 expr = tsubst_copy (name, args, complain, in_decl);
12004 if (dependent_scope_p (scope))
12007 expr = build_min_nt_loc (loc, TEMPLATE_ID_EXPR, expr, template_args);
12008 return build_qualified_name (NULL_TREE, scope, expr,
12009 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
12012 if (!BASELINK_P (name) && !DECL_P (expr))
12014 if (TREE_CODE (expr) == BIT_NOT_EXPR)
12016 /* A BIT_NOT_EXPR is used to represent a destructor. */
12017 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
12019 error ("qualifying type %qT does not match destructor name ~%qT",
12020 scope, TREE_OPERAND (expr, 0));
12021 expr = error_mark_node;
12024 expr = lookup_qualified_name (scope, complete_dtor_identifier,
12025 /*is_type_p=*/0, false);
12028 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
12029 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
12030 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
12032 if (complain & tf_error)
12034 error ("dependent-name %qE is parsed as a non-type, but "
12035 "instantiation yields a type", qualified_id);
12036 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
12038 return error_mark_node;
12044 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
12046 /* Remember that there was a reference to this entity. */
12050 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
12052 if (complain & tf_error)
12053 qualified_name_lookup_error (scope,
12054 TREE_OPERAND (qualified_id, 1),
12055 expr, input_location);
12056 return error_mark_node;
12060 expr = lookup_template_function (expr, template_args);
12062 if (expr == error_mark_node && complain & tf_error)
12063 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
12064 expr, input_location);
12065 else if (TYPE_P (scope))
12067 expr = (adjust_result_of_qualified_name_lookup
12068 (expr, scope, current_nonlambda_class_type ()));
12069 expr = (finish_qualified_id_expr
12070 (scope, expr, done, address_p && PTRMEM_OK_P (qualified_id),
12071 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
12072 /*template_arg_p=*/false, complain));
12075 /* Expressions do not generally have reference type. */
12076 if (TREE_CODE (expr) != SCOPE_REF
12077 /* However, if we're about to form a pointer-to-member, we just
12078 want the referenced member referenced. */
12079 && TREE_CODE (expr) != OFFSET_REF)
12080 expr = convert_from_reference (expr);
12085 /* Like tsubst, but deals with expressions. This function just replaces
12086 template parms; to finish processing the resultant expression, use
12087 tsubst_copy_and_build or tsubst_expr. */
12090 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
12092 enum tree_code code;
12095 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
12098 code = TREE_CODE (t);
12103 r = retrieve_local_specialization (t);
12105 if (r == NULL_TREE)
12107 /* We get here for a use of 'this' in an NSDMI. */
12108 if (DECL_NAME (t) == this_identifier
12109 && at_function_scope_p ()
12110 && DECL_CONSTRUCTOR_P (current_function_decl))
12111 return current_class_ptr;
12113 /* This can happen for a parameter name used later in a function
12114 declaration (such as in a late-specified return type). Just
12115 make a dummy decl, since it's only used for its type. */
12116 gcc_assert (cp_unevaluated_operand != 0);
12117 r = tsubst_decl (t, args, complain);
12118 /* Give it the template pattern as its context; its true context
12119 hasn't been instantiated yet and this is good enough for
12121 DECL_CONTEXT (r) = DECL_CONTEXT (t);
12124 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
12125 r = ARGUMENT_PACK_SELECT_ARG (r);
12134 if (DECL_TEMPLATE_PARM_P (t))
12135 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
12136 /* There is no need to substitute into namespace-scope
12138 if (DECL_NAMESPACE_SCOPE_P (t))
12140 /* If ARGS is NULL, then T is known to be non-dependent. */
12141 if (args == NULL_TREE)
12142 return integral_constant_value (t);
12144 /* Unfortunately, we cannot just call lookup_name here.
12147 template <int I> int f() {
12149 struct S { void g() { E e = a; } };
12152 When we instantiate f<7>::S::g(), say, lookup_name is not
12153 clever enough to find f<7>::a. */
12155 = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
12156 /*entering_scope=*/0);
12158 for (v = TYPE_VALUES (enum_type);
12160 v = TREE_CHAIN (v))
12161 if (TREE_PURPOSE (v) == DECL_NAME (t))
12162 return TREE_VALUE (v);
12164 /* We didn't find the name. That should never happen; if
12165 name-lookup found it during preliminary parsing, we
12166 should find it again here during instantiation. */
12167 gcc_unreachable ();
12172 if (DECL_CONTEXT (t))
12176 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
12177 /*entering_scope=*/1);
12178 if (ctx != DECL_CONTEXT (t))
12180 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
12183 if (complain & tf_error)
12184 error ("using invalid field %qD", t);
12185 return error_mark_node;
12194 case FUNCTION_DECL:
12195 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
12196 || local_variable_p (t))
12197 t = tsubst (t, args, complain, in_decl);
12201 case NAMESPACE_DECL:
12205 /* An OVERLOAD will always be a non-dependent overload set; an
12206 overload set from function scope will just be represented with an
12207 IDENTIFIER_NODE, and from class scope with a BASELINK. */
12208 gcc_assert (!uses_template_parms (t));
12212 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
12214 case TEMPLATE_DECL:
12215 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
12216 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
12217 args, complain, in_decl);
12218 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
12219 return tsubst (t, args, complain, in_decl);
12220 else if (DECL_CLASS_SCOPE_P (t)
12221 && uses_template_parms (DECL_CONTEXT (t)))
12223 /* Template template argument like the following example need
12226 template <template <class> class TT> struct C {};
12227 template <class T> struct D {
12228 template <class U> struct E {};
12233 We are processing the template argument `E' in #1 for
12234 the template instantiation #2. Originally, `E' is a
12235 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
12236 have to substitute this with one having context `D<int>'. */
12238 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
12239 return lookup_field (context, DECL_NAME(t), 0, false);
12242 /* Ordinary template template argument. */
12246 case REINTERPRET_CAST_EXPR:
12247 case CONST_CAST_EXPR:
12248 case STATIC_CAST_EXPR:
12249 case DYNAMIC_CAST_EXPR:
12250 case IMPLICIT_CONV_EXPR:
12254 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12255 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12258 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
12261 tree expanded, op = TREE_OPERAND (t, 0);
12264 if (SIZEOF_EXPR_TYPE_P (t))
12265 op = TREE_TYPE (op);
12267 ++cp_unevaluated_operand;
12268 ++c_inhibit_evaluation_warnings;
12269 /* We only want to compute the number of arguments. */
12270 expanded = tsubst_pack_expansion (op, args, complain, in_decl);
12271 --cp_unevaluated_operand;
12272 --c_inhibit_evaluation_warnings;
12274 if (TREE_CODE (expanded) == TREE_VEC)
12275 len = TREE_VEC_LENGTH (expanded);
12277 if (expanded == error_mark_node)
12278 return error_mark_node;
12279 else if (PACK_EXPANSION_P (expanded)
12280 || (TREE_CODE (expanded) == TREE_VEC
12282 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
12284 if (TREE_CODE (expanded) == TREE_VEC)
12285 expanded = TREE_VEC_ELT (expanded, len - 1);
12287 if (TYPE_P (expanded))
12288 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
12289 complain & tf_error);
12291 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
12292 complain & tf_error);
12295 return build_int_cst (size_type_node, len);
12297 if (SIZEOF_EXPR_TYPE_P (t))
12299 r = tsubst (TREE_TYPE (TREE_OPERAND (t, 0)),
12300 args, complain, in_decl);
12301 r = build1 (NOP_EXPR, r, error_mark_node);
12302 r = build1 (SIZEOF_EXPR,
12303 tsubst (TREE_TYPE (t), args, complain, in_decl), r);
12304 SIZEOF_EXPR_TYPE_P (r) = 1;
12311 case TRUTH_NOT_EXPR:
12314 case UNARY_PLUS_EXPR: /* Unary + */
12316 case AT_ENCODE_EXPR:
12320 case REALPART_EXPR:
12321 case IMAGPART_EXPR:
12323 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12324 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
12326 case COMPONENT_REF:
12331 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
12332 name = TREE_OPERAND (t, 1);
12333 if (TREE_CODE (name) == BIT_NOT_EXPR)
12335 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12336 complain, in_decl);
12337 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12339 else if (TREE_CODE (name) == SCOPE_REF
12340 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
12342 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
12343 complain, in_decl);
12344 name = TREE_OPERAND (name, 1);
12345 name = tsubst_copy (TREE_OPERAND (name, 0), args,
12346 complain, in_decl);
12347 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
12348 name = build_qualified_name (/*type=*/NULL_TREE,
12350 /*template_p=*/false);
12352 else if (BASELINK_P (name))
12353 name = tsubst_baselink (name,
12354 non_reference (TREE_TYPE (object)),
12358 name = tsubst_copy (name, args, complain, in_decl);
12359 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
12365 case TRUNC_DIV_EXPR:
12366 case CEIL_DIV_EXPR:
12367 case FLOOR_DIV_EXPR:
12368 case ROUND_DIV_EXPR:
12369 case EXACT_DIV_EXPR:
12373 case TRUNC_MOD_EXPR:
12374 case FLOOR_MOD_EXPR:
12375 case TRUTH_ANDIF_EXPR:
12376 case TRUTH_ORIF_EXPR:
12377 case TRUTH_AND_EXPR:
12378 case TRUTH_OR_EXPR:
12391 case COMPOUND_EXPR:
12394 case PREDECREMENT_EXPR:
12395 case PREINCREMENT_EXPR:
12396 case POSTDECREMENT_EXPR:
12397 case POSTINCREMENT_EXPR:
12399 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12400 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12403 return build_qualified_name (/*type=*/NULL_TREE,
12404 tsubst_copy (TREE_OPERAND (t, 0),
12405 args, complain, in_decl),
12406 tsubst_copy (TREE_OPERAND (t, 1),
12407 args, complain, in_decl),
12408 QUALIFIED_NAME_IS_TEMPLATE (t));
12413 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12414 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12415 NULL_TREE, NULL_TREE);
12419 int n = VL_EXP_OPERAND_LENGTH (t);
12420 tree result = build_vl_exp (CALL_EXPR, n);
12422 for (i = 0; i < n; i++)
12423 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
12424 complain, in_decl);
12430 case PSEUDO_DTOR_EXPR:
12433 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12434 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12435 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12436 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
12443 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12444 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
12445 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
12446 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
12453 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12454 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12455 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
12456 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
12460 case TEMPLATE_ID_EXPR:
12462 /* Substituted template arguments */
12463 tree fn = TREE_OPERAND (t, 0);
12464 tree targs = TREE_OPERAND (t, 1);
12466 fn = tsubst_copy (fn, args, complain, in_decl);
12468 targs = tsubst_template_args (targs, args, complain, in_decl);
12470 return lookup_template_function (fn, targs);
12475 tree purpose, value, chain;
12477 if (t == void_list_node)
12480 purpose = TREE_PURPOSE (t);
12482 purpose = tsubst_copy (purpose, args, complain, in_decl);
12483 value = TREE_VALUE (t);
12485 value = tsubst_copy (value, args, complain, in_decl);
12486 chain = TREE_CHAIN (t);
12487 if (chain && chain != void_type_node)
12488 chain = tsubst_copy (chain, args, complain, in_decl);
12489 if (purpose == TREE_PURPOSE (t)
12490 && value == TREE_VALUE (t)
12491 && chain == TREE_CHAIN (t))
12493 return tree_cons (purpose, value, chain);
12498 case ENUMERAL_TYPE:
12500 case TEMPLATE_TYPE_PARM:
12501 case TEMPLATE_TEMPLATE_PARM:
12502 case BOUND_TEMPLATE_TEMPLATE_PARM:
12503 case TEMPLATE_PARM_INDEX:
12505 case REFERENCE_TYPE:
12507 case FUNCTION_TYPE:
12510 case TYPENAME_TYPE:
12511 case UNBOUND_CLASS_TEMPLATE:
12513 case DECLTYPE_TYPE:
12515 return tsubst (t, args, complain, in_decl);
12519 /* Fall through. */
12520 case IDENTIFIER_NODE:
12521 if (IDENTIFIER_TYPENAME_P (t))
12523 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12524 return mangle_conv_op_name_for_type (new_type);
12530 /* This is handled by tsubst_copy_and_build. */
12531 gcc_unreachable ();
12534 return build_x_va_arg (EXPR_LOCATION (t),
12535 tsubst_copy (TREE_OPERAND (t, 0), args, complain,
12537 tsubst (TREE_TYPE (t), args, complain, in_decl));
12539 case CLEANUP_POINT_EXPR:
12540 /* We shouldn't have built any of these during initial template
12541 generation. Instead, they should be built during instantiation
12542 in response to the saved STMT_IS_FULL_EXPR_P setting. */
12543 gcc_unreachable ();
12547 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
12548 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
12549 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
12550 PTRMEM_OK_P (r) = PTRMEM_OK_P (t);
12551 mark_used (TREE_OPERAND (r, 1));
12554 case EXPR_PACK_EXPANSION:
12555 error ("invalid use of pack expansion expression");
12556 return error_mark_node;
12558 case NONTYPE_ARGUMENT_PACK:
12559 error ("use %<...%> to expand argument pack");
12560 return error_mark_node;
12567 /* Instantiate any typedefs in the type. */
12568 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12569 r = fold_convert (type, t);
12570 gcc_assert (TREE_CODE (r) == code);
12575 /* These can sometimes show up in a partial instantiation, but never
12576 involve template parms. */
12577 gcc_assert (!uses_template_parms (t));
12581 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */
12582 gcc_checking_assert (false);
12587 /* Like tsubst_copy, but specifically for OpenMP clauses. */
12590 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
12593 tree new_clauses = NULL, nc, oc;
12595 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
12597 nc = copy_node (oc);
12598 OMP_CLAUSE_CHAIN (nc) = new_clauses;
12601 switch (OMP_CLAUSE_CODE (nc))
12603 case OMP_CLAUSE_LASTPRIVATE:
12604 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
12606 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
12607 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
12608 in_decl, /*integral_constant_expression_p=*/false);
12609 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
12610 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
12613 case OMP_CLAUSE_PRIVATE:
12614 case OMP_CLAUSE_SHARED:
12615 case OMP_CLAUSE_FIRSTPRIVATE:
12616 case OMP_CLAUSE_REDUCTION:
12617 case OMP_CLAUSE_COPYIN:
12618 case OMP_CLAUSE_COPYPRIVATE:
12619 case OMP_CLAUSE_IF:
12620 case OMP_CLAUSE_NUM_THREADS:
12621 case OMP_CLAUSE_SCHEDULE:
12622 case OMP_CLAUSE_COLLAPSE:
12623 case OMP_CLAUSE_FINAL:
12624 OMP_CLAUSE_OPERAND (nc, 0)
12625 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
12626 in_decl, /*integral_constant_expression_p=*/false);
12628 case OMP_CLAUSE_NOWAIT:
12629 case OMP_CLAUSE_ORDERED:
12630 case OMP_CLAUSE_DEFAULT:
12631 case OMP_CLAUSE_UNTIED:
12632 case OMP_CLAUSE_MERGEABLE:
12635 gcc_unreachable ();
12639 return finish_omp_clauses (nreverse (new_clauses));
12642 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
12645 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
12648 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
12650 tree purpose, value, chain;
12655 if (TREE_CODE (t) != TREE_LIST)
12656 return tsubst_copy_and_build (t, args, complain, in_decl,
12657 /*function_p=*/false,
12658 /*integral_constant_expression_p=*/false);
12660 if (t == void_list_node)
12663 purpose = TREE_PURPOSE (t);
12665 purpose = RECUR (purpose);
12666 value = TREE_VALUE (t);
12669 if (TREE_CODE (value) != LABEL_DECL)
12670 value = RECUR (value);
12673 value = lookup_label (DECL_NAME (value));
12674 gcc_assert (TREE_CODE (value) == LABEL_DECL);
12675 TREE_USED (value) = 1;
12678 chain = TREE_CHAIN (t);
12679 if (chain && chain != void_type_node)
12680 chain = RECUR (chain);
12681 return tree_cons (purpose, value, chain);
12685 /* Substitute one OMP_FOR iterator. */
12688 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
12689 tree condv, tree incrv, tree *clauses,
12690 tree args, tsubst_flags_t complain, tree in_decl,
12691 bool integral_constant_expression_p)
12693 #define RECUR(NODE) \
12694 tsubst_expr ((NODE), args, complain, in_decl, \
12695 integral_constant_expression_p)
12696 tree decl, init, cond, incr;
12699 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
12700 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
12701 decl = TREE_OPERAND (init, 0);
12702 init = TREE_OPERAND (init, 1);
12703 /* Do this before substituting into decl to handle 'auto'. */
12704 init_decl = (init && TREE_CODE (init) == DECL_EXPR);
12705 init = RECUR (init);
12706 decl = RECUR (decl);
12709 gcc_assert (!processing_template_decl);
12710 init = DECL_INITIAL (decl);
12711 DECL_INITIAL (decl) = NULL_TREE;
12714 gcc_assert (!type_dependent_expression_p (decl));
12716 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
12718 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
12719 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12720 if (TREE_CODE (incr) == MODIFY_EXPR)
12721 incr = build_x_modify_expr (EXPR_LOCATION (incr),
12722 RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
12723 RECUR (TREE_OPERAND (incr, 1)),
12726 incr = RECUR (incr);
12727 TREE_VEC_ELT (declv, i) = decl;
12728 TREE_VEC_ELT (initv, i) = init;
12729 TREE_VEC_ELT (condv, i) = cond;
12730 TREE_VEC_ELT (incrv, i) = incr;
12734 if (init && !init_decl)
12737 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
12739 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
12740 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
12741 && OMP_CLAUSE_DECL (c) == decl)
12743 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
12744 && OMP_CLAUSE_DECL (c) == decl)
12745 error ("iteration variable %qD should not be firstprivate", decl);
12746 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
12747 && OMP_CLAUSE_DECL (c) == decl)
12748 error ("iteration variable %qD should not be reduction", decl);
12752 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
12753 OMP_CLAUSE_DECL (c) = decl;
12754 c = finish_omp_clauses (c);
12757 OMP_CLAUSE_CHAIN (c) = *clauses;
12762 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
12763 if (COMPARISON_CLASS_P (cond))
12764 cond = build2 (TREE_CODE (cond), boolean_type_node,
12765 RECUR (TREE_OPERAND (cond, 0)),
12766 RECUR (TREE_OPERAND (cond, 1)));
12768 cond = RECUR (cond);
12769 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
12770 switch (TREE_CODE (incr))
12772 case PREINCREMENT_EXPR:
12773 case PREDECREMENT_EXPR:
12774 case POSTINCREMENT_EXPR:
12775 case POSTDECREMENT_EXPR:
12776 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
12777 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
12780 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12781 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12783 tree rhs = TREE_OPERAND (incr, 1);
12784 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12785 RECUR (TREE_OPERAND (incr, 0)),
12786 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12787 RECUR (TREE_OPERAND (rhs, 0)),
12788 RECUR (TREE_OPERAND (rhs, 1))));
12791 incr = RECUR (incr);
12794 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
12795 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
12797 tree lhs = RECUR (TREE_OPERAND (incr, 0));
12798 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
12799 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
12800 TREE_TYPE (decl), lhs,
12801 RECUR (TREE_OPERAND (incr, 2))));
12803 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
12804 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
12805 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
12807 tree rhs = TREE_OPERAND (incr, 2);
12808 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
12809 RECUR (TREE_OPERAND (incr, 0)),
12810 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
12811 RECUR (TREE_OPERAND (rhs, 0)),
12812 RECUR (TREE_OPERAND (rhs, 1))));
12815 incr = RECUR (incr);
12818 incr = RECUR (incr);
12822 TREE_VEC_ELT (declv, i) = decl;
12823 TREE_VEC_ELT (initv, i) = init;
12824 TREE_VEC_ELT (condv, i) = cond;
12825 TREE_VEC_ELT (incrv, i) = incr;
12829 /* Like tsubst_copy for expressions, etc. but also does semantic
12833 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
12834 bool integral_constant_expression_p)
12836 #define RETURN(EXP) do { r = (EXP); goto out; } while(0)
12837 #define RECUR(NODE) \
12838 tsubst_expr ((NODE), args, complain, in_decl, \
12839 integral_constant_expression_p)
12845 if (t == NULL_TREE || t == error_mark_node)
12848 loc = input_location;
12849 if (EXPR_HAS_LOCATION (t))
12850 input_location = EXPR_LOCATION (t);
12851 if (STATEMENT_CODE_P (TREE_CODE (t)))
12852 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
12854 switch (TREE_CODE (t))
12856 case STATEMENT_LIST:
12858 tree_stmt_iterator i;
12859 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
12860 RECUR (tsi_stmt (i));
12864 case CTOR_INITIALIZER:
12865 finish_mem_initializers (tsubst_initializer_list
12866 (TREE_OPERAND (t, 0), args));
12870 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
12874 tmp = RECUR (EXPR_STMT_EXPR (t));
12875 if (EXPR_STMT_STMT_EXPR_RESULT (t))
12876 finish_stmt_expr_expr (tmp, cur_stmt_expr);
12878 finish_expr_stmt (tmp);
12882 do_using_directive (USING_STMT_NAMESPACE (t));
12887 tree decl, pattern_decl;
12890 pattern_decl = decl = DECL_EXPR_DECL (t);
12891 if (TREE_CODE (decl) == LABEL_DECL)
12892 finish_label_decl (DECL_NAME (decl));
12893 else if (TREE_CODE (decl) == USING_DECL)
12895 tree scope = USING_DECL_SCOPE (decl);
12896 tree name = DECL_NAME (decl);
12899 scope = tsubst (scope, args, complain, in_decl);
12900 decl = lookup_qualified_name (scope, name,
12901 /*is_type_p=*/false,
12902 /*complain=*/false);
12903 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
12904 qualified_name_lookup_error (scope, name, decl, input_location);
12906 do_local_using_decl (decl, scope, name);
12910 init = DECL_INITIAL (decl);
12911 decl = tsubst (decl, args, complain, in_decl);
12912 if (decl != error_mark_node)
12914 /* By marking the declaration as instantiated, we avoid
12915 trying to instantiate it. Since instantiate_decl can't
12916 handle local variables, and since we've already done
12917 all that needs to be done, that's the right thing to
12919 if (TREE_CODE (decl) == VAR_DECL)
12920 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
12921 if (TREE_CODE (decl) == VAR_DECL
12922 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
12923 /* Anonymous aggregates are a special case. */
12924 finish_anon_union (decl);
12925 else if (is_capture_proxy (DECL_EXPR_DECL (t)))
12927 DECL_CONTEXT (decl) = current_function_decl;
12928 if (DECL_NAME (decl) == this_identifier)
12930 tree lam = DECL_CONTEXT (current_function_decl);
12931 lam = CLASSTYPE_LAMBDA_EXPR (lam);
12932 LAMBDA_EXPR_THIS_CAPTURE (lam) = decl;
12934 insert_capture_proxy (decl);
12936 else if (DECL_IMPLICIT_TYPEDEF_P (t))
12937 /* We already did a pushtag. */;
12940 int const_init = false;
12941 maybe_push_decl (decl);
12942 if (TREE_CODE (decl) == VAR_DECL
12943 && DECL_PRETTY_FUNCTION_P (decl))
12945 /* For __PRETTY_FUNCTION__ we have to adjust the
12947 const char *const name
12948 = cxx_printable_name (current_function_decl, 2);
12949 init = cp_fname_init (name, &TREE_TYPE (decl));
12953 tree t = RECUR (init);
12957 /* If we had an initializer but it
12958 instantiated to nothing,
12959 value-initialize the object. This will
12960 only occur when the initializer was a
12961 pack expansion where the parameter packs
12962 used in that expansion were of length
12964 init = build_value_init (TREE_TYPE (decl),
12966 if (TREE_CODE (init) == AGGR_INIT_EXPR)
12967 init = get_target_expr_sfinae (init, complain);
12973 if (TREE_CODE (decl) == VAR_DECL)
12974 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P
12976 cp_finish_decl (decl, init, const_init, NULL_TREE, 0);
12985 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
12986 RECUR (FOR_INIT_STMT (t));
12987 finish_for_init_stmt (stmt);
12988 tmp = RECUR (FOR_COND (t));
12989 finish_for_cond (tmp, stmt);
12990 tmp = RECUR (FOR_EXPR (t));
12991 finish_for_expr (tmp, stmt);
12992 RECUR (FOR_BODY (t));
12993 finish_for_stmt (stmt);
12996 case RANGE_FOR_STMT:
12999 stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
13000 decl = RANGE_FOR_DECL (t);
13001 decl = tsubst (decl, args, complain, in_decl);
13002 maybe_push_decl (decl);
13003 expr = RECUR (RANGE_FOR_EXPR (t));
13004 stmt = cp_convert_range_for (stmt, decl, expr);
13005 RECUR (RANGE_FOR_BODY (t));
13006 finish_for_stmt (stmt);
13011 stmt = begin_while_stmt ();
13012 tmp = RECUR (WHILE_COND (t));
13013 finish_while_stmt_cond (tmp, stmt);
13014 RECUR (WHILE_BODY (t));
13015 finish_while_stmt (stmt);
13019 stmt = begin_do_stmt ();
13020 RECUR (DO_BODY (t));
13021 finish_do_body (stmt);
13022 tmp = RECUR (DO_COND (t));
13023 finish_do_stmt (tmp, stmt);
13027 stmt = begin_if_stmt ();
13028 tmp = RECUR (IF_COND (t));
13029 finish_if_stmt_cond (tmp, stmt);
13030 RECUR (THEN_CLAUSE (t));
13031 finish_then_clause (stmt);
13033 if (ELSE_CLAUSE (t))
13035 begin_else_clause (stmt);
13036 RECUR (ELSE_CLAUSE (t));
13037 finish_else_clause (stmt);
13040 finish_if_stmt (stmt);
13044 if (BIND_EXPR_BODY_BLOCK (t))
13045 stmt = begin_function_body ();
13047 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
13048 ? BCS_TRY_BLOCK : 0);
13050 RECUR (BIND_EXPR_BODY (t));
13052 if (BIND_EXPR_BODY_BLOCK (t))
13053 finish_function_body (stmt);
13055 finish_compound_stmt (stmt);
13059 finish_break_stmt ();
13062 case CONTINUE_STMT:
13063 finish_continue_stmt ();
13067 stmt = begin_switch_stmt ();
13068 tmp = RECUR (SWITCH_STMT_COND (t));
13069 finish_switch_cond (tmp, stmt);
13070 RECUR (SWITCH_STMT_BODY (t));
13071 finish_switch_stmt (stmt);
13074 case CASE_LABEL_EXPR:
13075 finish_case_label (EXPR_LOCATION (t),
13076 RECUR (CASE_LOW (t)),
13077 RECUR (CASE_HIGH (t)));
13082 tree decl = LABEL_EXPR_LABEL (t);
13085 label = finish_label_stmt (DECL_NAME (decl));
13086 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
13087 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
13092 tmp = GOTO_DESTINATION (t);
13093 if (TREE_CODE (tmp) != LABEL_DECL)
13094 /* Computed goto's must be tsubst'd into. On the other hand,
13095 non-computed gotos must not be; the identifier in question
13096 will have no binding. */
13099 tmp = DECL_NAME (tmp);
13100 finish_goto_stmt (tmp);
13104 tmp = finish_asm_stmt
13105 (ASM_VOLATILE_P (t),
13106 RECUR (ASM_STRING (t)),
13107 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
13108 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
13109 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl),
13110 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl));
13112 tree asm_expr = tmp;
13113 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
13114 asm_expr = TREE_OPERAND (asm_expr, 0);
13115 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
13122 stmt = begin_try_block ();
13123 RECUR (TRY_STMTS (t));
13124 finish_cleanup_try_block (stmt);
13125 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
13129 tree compound_stmt = NULL_TREE;
13131 if (FN_TRY_BLOCK_P (t))
13132 stmt = begin_function_try_block (&compound_stmt);
13134 stmt = begin_try_block ();
13136 RECUR (TRY_STMTS (t));
13138 if (FN_TRY_BLOCK_P (t))
13139 finish_function_try_block (stmt);
13141 finish_try_block (stmt);
13143 RECUR (TRY_HANDLERS (t));
13144 if (FN_TRY_BLOCK_P (t))
13145 finish_function_handler_sequence (stmt, compound_stmt);
13147 finish_handler_sequence (stmt);
13153 tree decl = HANDLER_PARMS (t);
13157 decl = tsubst (decl, args, complain, in_decl);
13158 /* Prevent instantiate_decl from trying to instantiate
13159 this variable. We've already done all that needs to be
13161 if (decl != error_mark_node)
13162 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
13164 stmt = begin_handler ();
13165 finish_handler_parms (decl, stmt);
13166 RECUR (HANDLER_BODY (t));
13167 finish_handler (stmt);
13172 tmp = tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
13173 if (CLASS_TYPE_P (tmp))
13175 /* Local classes are not independent templates; they are
13176 instantiated along with their containing function. And this
13177 way we don't have to deal with pushing out of one local class
13178 to instantiate a member of another local class. */
13180 /* Closures are handled by the LAMBDA_EXPR. */
13181 gcc_assert (!LAMBDA_TYPE_P (TREE_TYPE (t)));
13182 complete_type (tmp);
13183 for (fn = TYPE_METHODS (tmp); fn; fn = DECL_CHAIN (fn))
13184 if (!DECL_ARTIFICIAL (fn))
13185 instantiate_decl (fn, /*defer_ok*/0, /*expl_inst_class*/false);
13189 case STATIC_ASSERT:
13193 ++c_inhibit_evaluation_warnings;
13195 tsubst_expr (STATIC_ASSERT_CONDITION (t),
13198 /*integral_constant_expression_p=*/true);
13199 --c_inhibit_evaluation_warnings;
13201 finish_static_assert (condition,
13202 STATIC_ASSERT_MESSAGE (t),
13203 STATIC_ASSERT_SOURCE_LOCATION (t),
13204 /*member_p=*/false);
13209 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
13210 args, complain, in_decl);
13211 stmt = begin_omp_parallel ();
13212 RECUR (OMP_PARALLEL_BODY (t));
13213 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
13214 = OMP_PARALLEL_COMBINED (t);
13218 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
13219 args, complain, in_decl);
13220 stmt = begin_omp_task ();
13221 RECUR (OMP_TASK_BODY (t));
13222 finish_omp_task (tmp, stmt);
13227 tree clauses, body, pre_body;
13228 tree declv, initv, condv, incrv;
13231 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
13232 args, complain, in_decl);
13233 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13234 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13235 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13236 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
13238 stmt = begin_omp_structured_block ();
13240 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
13241 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
13242 &clauses, args, complain, in_decl,
13243 integral_constant_expression_p);
13245 pre_body = push_stmt_list ();
13246 RECUR (OMP_FOR_PRE_BODY (t));
13247 pre_body = pop_stmt_list (pre_body);
13249 body = push_stmt_list ();
13250 RECUR (OMP_FOR_BODY (t));
13251 body = pop_stmt_list (body);
13253 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
13254 body, pre_body, clauses);
13256 add_stmt (finish_omp_structured_block (stmt));
13262 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
13263 stmt = push_stmt_list ();
13264 RECUR (OMP_BODY (t));
13265 stmt = pop_stmt_list (stmt);
13268 OMP_BODY (t) = stmt;
13269 OMP_CLAUSES (t) = tmp;
13277 stmt = push_stmt_list ();
13278 RECUR (OMP_BODY (t));
13279 stmt = pop_stmt_list (stmt);
13282 OMP_BODY (t) = stmt;
13287 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
13288 if (TREE_CODE (TREE_OPERAND (t, 1)) != MODIFY_EXPR)
13290 tree op1 = TREE_OPERAND (t, 1);
13291 tree rhs1 = NULL_TREE;
13293 if (TREE_CODE (op1) == COMPOUND_EXPR)
13295 rhs1 = RECUR (TREE_OPERAND (op1, 0));
13296 op1 = TREE_OPERAND (op1, 1);
13298 lhs = RECUR (TREE_OPERAND (op1, 0));
13299 rhs = RECUR (TREE_OPERAND (op1, 1));
13300 finish_omp_atomic (OMP_ATOMIC, TREE_CODE (op1), lhs, rhs,
13301 NULL_TREE, NULL_TREE, rhs1);
13305 tree op1 = TREE_OPERAND (t, 1);
13306 tree v = NULL_TREE, lhs, rhs = NULL_TREE, lhs1 = NULL_TREE;
13307 tree rhs1 = NULL_TREE;
13308 enum tree_code code = TREE_CODE (TREE_OPERAND (op1, 1));
13309 enum tree_code opcode = NOP_EXPR;
13310 if (code == OMP_ATOMIC_READ)
13312 v = RECUR (TREE_OPERAND (op1, 0));
13313 lhs = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13315 else if (code == OMP_ATOMIC_CAPTURE_OLD
13316 || code == OMP_ATOMIC_CAPTURE_NEW)
13318 tree op11 = TREE_OPERAND (TREE_OPERAND (op1, 1), 1);
13319 v = RECUR (TREE_OPERAND (op1, 0));
13320 lhs1 = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0));
13321 if (TREE_CODE (op11) == COMPOUND_EXPR)
13323 rhs1 = RECUR (TREE_OPERAND (op11, 0));
13324 op11 = TREE_OPERAND (op11, 1);
13326 lhs = RECUR (TREE_OPERAND (op11, 0));
13327 rhs = RECUR (TREE_OPERAND (op11, 1));
13328 opcode = TREE_CODE (op11);
13333 lhs = RECUR (TREE_OPERAND (op1, 0));
13334 rhs = RECUR (TREE_OPERAND (op1, 1));
13336 finish_omp_atomic (code, opcode, lhs, rhs, v, lhs1, rhs1);
13340 case TRANSACTION_EXPR:
13343 flags |= (TRANSACTION_EXPR_OUTER (t) ? TM_STMT_ATTR_OUTER : 0);
13344 flags |= (TRANSACTION_EXPR_RELAXED (t) ? TM_STMT_ATTR_RELAXED : 0);
13346 if (TRANSACTION_EXPR_IS_STMT (t))
13348 tree body = TRANSACTION_EXPR_BODY (t);
13349 tree noex = NULL_TREE;
13350 if (TREE_CODE (body) == MUST_NOT_THROW_EXPR)
13352 noex = MUST_NOT_THROW_COND (body);
13353 if (noex == NULL_TREE)
13354 noex = boolean_true_node;
13355 body = TREE_OPERAND (body, 0);
13357 stmt = begin_transaction_stmt (input_location, NULL, flags);
13359 finish_transaction_stmt (stmt, NULL, flags, RECUR (noex));
13363 stmt = build_transaction_expr (EXPR_LOCATION (t),
13364 RECUR (TRANSACTION_EXPR_BODY (t)),
13371 case MUST_NOT_THROW_EXPR:
13372 RETURN (build_must_not_throw_expr (RECUR (TREE_OPERAND (t, 0)),
13373 RECUR (MUST_NOT_THROW_COND (t))));
13375 case EXPR_PACK_EXPANSION:
13376 error ("invalid use of pack expansion expression");
13377 RETURN (error_mark_node);
13379 case NONTYPE_ARGUMENT_PACK:
13380 error ("use %<...%> to expand argument pack");
13381 RETURN (error_mark_node);
13383 case COMPOUND_EXPR:
13384 tmp = RECUR (TREE_OPERAND (t, 0));
13385 if (tmp == NULL_TREE)
13386 /* If the first operand was a statement, we're done with it. */
13387 RETURN (RECUR (TREE_OPERAND (t, 1)));
13388 RETURN (build_x_compound_expr (EXPR_LOCATION (t), tmp,
13389 RECUR (TREE_OPERAND (t, 1)),
13393 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
13395 RETURN (tsubst_copy_and_build (t, args, complain, in_decl,
13396 /*function_p=*/false,
13397 integral_constant_expression_p));
13400 RETURN (NULL_TREE);
13402 input_location = loc;
13408 /* T is a postfix-expression that is not being used in a function
13409 call. Return the substituted version of T. */
13412 tsubst_non_call_postfix_expression (tree t, tree args,
13413 tsubst_flags_t complain,
13416 if (TREE_CODE (t) == SCOPE_REF)
13417 t = tsubst_qualified_id (t, args, complain, in_decl,
13418 /*done=*/false, /*address_p=*/false);
13420 t = tsubst_copy_and_build (t, args, complain, in_decl,
13421 /*function_p=*/false,
13422 /*integral_constant_expression_p=*/false);
13427 /* Like tsubst but deals with expressions and performs semantic
13428 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
13431 tsubst_copy_and_build (tree t,
13433 tsubst_flags_t complain,
13436 bool integral_constant_expression_p)
13438 #define RETURN(EXP) do { retval = (EXP); goto out; } while(0)
13439 #define RECUR(NODE) \
13440 tsubst_copy_and_build (NODE, args, complain, in_decl, \
13441 /*function_p=*/false, \
13442 integral_constant_expression_p)
13447 if (t == NULL_TREE || t == error_mark_node)
13450 loc = input_location;
13451 if (EXPR_HAS_LOCATION (t))
13452 input_location = EXPR_LOCATION (t);
13454 /* N3276 decltype magic only applies to calls at the top level or on the
13455 right side of a comma. */
13456 tsubst_flags_t decltype_flag = (complain & tf_decltype);
13457 complain &= ~tf_decltype;
13459 switch (TREE_CODE (t))
13463 /* Fall through. */
13464 case IDENTIFIER_NODE:
13468 bool non_integral_constant_expression_p;
13469 const char *error_msg;
13471 if (IDENTIFIER_TYPENAME_P (t))
13473 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13474 t = mangle_conv_op_name_for_type (new_type);
13477 /* Look up the name. */
13478 decl = lookup_name (t);
13480 /* By convention, expressions use ERROR_MARK_NODE to indicate
13481 failure, not NULL_TREE. */
13482 if (decl == NULL_TREE)
13483 decl = error_mark_node;
13485 decl = finish_id_expression (t, decl, NULL_TREE,
13487 integral_constant_expression_p,
13488 /*allow_non_integral_constant_expression_p=*/(cxx_dialect >= cxx0x),
13489 &non_integral_constant_expression_p,
13490 /*template_p=*/false,
13492 /*address_p=*/false,
13493 /*template_arg_p=*/false,
13498 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
13500 if (complain & tf_error)
13501 unqualified_name_lookup_error (decl);
13502 decl = error_mark_node;
13507 case TEMPLATE_ID_EXPR:
13510 tree templ = RECUR (TREE_OPERAND (t, 0));
13511 tree targs = TREE_OPERAND (t, 1);
13514 targs = tsubst_template_args (targs, args, complain, in_decl);
13516 if (TREE_CODE (templ) == COMPONENT_REF)
13518 object = TREE_OPERAND (templ, 0);
13519 templ = TREE_OPERAND (templ, 1);
13522 object = NULL_TREE;
13523 templ = lookup_template_function (templ, targs);
13526 RETURN (build3 (COMPONENT_REF, TREE_TYPE (templ),
13527 object, templ, NULL_TREE));
13529 RETURN (baselink_for_fns (templ));
13534 tree r = RECUR (TREE_OPERAND (t, 0));
13536 if (REFERENCE_REF_P (t))
13538 /* A type conversion to reference type will be enclosed in
13539 such an indirect ref, but the substitution of the cast
13540 will have also added such an indirect ref. */
13541 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
13542 r = convert_from_reference (r);
13545 r = build_x_indirect_ref (input_location, r, RO_UNARY_STAR,
13546 complain|decltype_flag);
13552 (tsubst (TREE_TYPE (t), args, complain, in_decl),
13553 RECUR (TREE_OPERAND (t, 0))));
13555 case IMPLICIT_CONV_EXPR:
13557 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13558 tree expr = RECUR (TREE_OPERAND (t, 0));
13559 int flags = LOOKUP_IMPLICIT;
13560 if (IMPLICIT_CONV_EXPR_DIRECT_INIT (t))
13561 flags = LOOKUP_NORMAL;
13562 RETURN (perform_implicit_conversion_flags (type, expr, complain,
13569 tsubst (TREE_TYPE (t), args, complain, in_decl),
13570 RECUR (TREE_OPERAND (t, 0))));
13573 case REINTERPRET_CAST_EXPR:
13574 case CONST_CAST_EXPR:
13575 case DYNAMIC_CAST_EXPR:
13576 case STATIC_CAST_EXPR:
13579 tree op, r = NULL_TREE;
13581 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
13582 if (integral_constant_expression_p
13583 && !cast_valid_in_integral_constant_expression_p (type))
13585 if (complain & tf_error)
13586 error ("a cast to a type other than an integral or "
13587 "enumeration type cannot appear in a constant-expression");
13588 RETURN (error_mark_node);
13591 op = RECUR (TREE_OPERAND (t, 0));
13593 ++c_inhibit_evaluation_warnings;
13594 switch (TREE_CODE (t))
13597 r = build_functional_cast (type, op, complain);
13599 case REINTERPRET_CAST_EXPR:
13600 r = build_reinterpret_cast (type, op, complain);
13602 case CONST_CAST_EXPR:
13603 r = build_const_cast (type, op, complain);
13605 case DYNAMIC_CAST_EXPR:
13606 r = build_dynamic_cast (type, op, complain);
13608 case STATIC_CAST_EXPR:
13609 r = build_static_cast (type, op, complain);
13612 gcc_unreachable ();
13614 --c_inhibit_evaluation_warnings;
13619 case POSTDECREMENT_EXPR:
13620 case POSTINCREMENT_EXPR:
13621 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13622 args, complain, in_decl);
13623 RETURN (build_x_unary_op (input_location, TREE_CODE (t), op1,
13624 complain|decltype_flag));
13626 case PREDECREMENT_EXPR:
13627 case PREINCREMENT_EXPR:
13631 case TRUTH_NOT_EXPR:
13632 case UNARY_PLUS_EXPR: /* Unary + */
13633 case REALPART_EXPR:
13634 case IMAGPART_EXPR:
13635 RETURN (build_x_unary_op (input_location, TREE_CODE (t),
13636 RECUR (TREE_OPERAND (t, 0)),
13637 complain|decltype_flag));
13639 case FIX_TRUNC_EXPR:
13640 RETURN (cp_build_unary_op (FIX_TRUNC_EXPR, RECUR (TREE_OPERAND (t, 0)),
13644 op1 = TREE_OPERAND (t, 0);
13645 if (TREE_CODE (op1) == LABEL_DECL)
13646 RETURN (finish_label_address_expr (DECL_NAME (op1),
13647 EXPR_LOCATION (op1)));
13648 if (TREE_CODE (op1) == SCOPE_REF)
13649 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
13650 /*done=*/true, /*address_p=*/true);
13652 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
13654 RETURN (build_x_unary_op (input_location, ADDR_EXPR, op1,
13655 complain|decltype_flag));
13660 case TRUNC_DIV_EXPR:
13661 case CEIL_DIV_EXPR:
13662 case FLOOR_DIV_EXPR:
13663 case ROUND_DIV_EXPR:
13664 case EXACT_DIV_EXPR:
13668 case TRUNC_MOD_EXPR:
13669 case FLOOR_MOD_EXPR:
13670 case TRUTH_ANDIF_EXPR:
13671 case TRUTH_ORIF_EXPR:
13672 case TRUTH_AND_EXPR:
13673 case TRUTH_OR_EXPR:
13691 ++c_inhibit_evaluation_warnings;
13693 r = build_x_binary_op
13694 (input_location, TREE_CODE (t),
13695 RECUR (TREE_OPERAND (t, 0)),
13696 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
13698 : TREE_CODE (TREE_OPERAND (t, 0))),
13699 RECUR (TREE_OPERAND (t, 1)),
13700 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
13702 : TREE_CODE (TREE_OPERAND (t, 1))),
13704 complain|decltype_flag);
13705 if (EXPR_P (r) && TREE_NO_WARNING (t))
13706 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13708 --c_inhibit_evaluation_warnings;
13714 RETURN (tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
13715 /*address_p=*/false));
13717 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13718 args, complain, in_decl);
13719 RETURN (build_x_array_ref (EXPR_LOCATION (t), op1,
13720 RECUR (TREE_OPERAND (t, 1)),
13721 complain|decltype_flag));
13724 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
13725 RETURN (tsubst_copy (t, args, complain, in_decl));
13732 op1 = TREE_OPERAND (t, 0);
13733 if (TREE_CODE (t) == SIZEOF_EXPR && SIZEOF_EXPR_TYPE_P (t))
13734 op1 = TREE_TYPE (op1);
13737 /* When there are no ARGS, we are trying to evaluate a
13738 non-dependent expression from the parser. Trying to do
13739 the substitutions may not work. */
13741 op1 = TREE_TYPE (op1);
13745 ++cp_unevaluated_operand;
13746 ++c_inhibit_evaluation_warnings;
13748 op1 = tsubst (op1, args, complain, in_decl);
13750 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13751 /*function_p=*/false,
13752 /*integral_constant_expression_p=*/
13754 --cp_unevaluated_operand;
13755 --c_inhibit_evaluation_warnings;
13758 r = cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
13759 complain & tf_error);
13761 r = cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
13762 complain & tf_error);
13763 if (TREE_CODE (t) == SIZEOF_EXPR && r != error_mark_node)
13765 if (TREE_CODE (r) != SIZEOF_EXPR || TYPE_P (op1))
13767 if (!processing_template_decl && TYPE_P (op1))
13769 r = build_min (SIZEOF_EXPR, size_type_node,
13770 build1 (NOP_EXPR, op1, error_mark_node));
13771 SIZEOF_EXPR_TYPE_P (r) = 1;
13774 r = build_min (SIZEOF_EXPR, size_type_node, op1);
13775 TREE_SIDE_EFFECTS (r) = 0;
13776 TREE_READONLY (r) = 1;
13778 SET_EXPR_LOCATION (r, EXPR_LOCATION (t));
13783 case AT_ENCODE_EXPR:
13785 op1 = TREE_OPERAND (t, 0);
13786 ++cp_unevaluated_operand;
13787 ++c_inhibit_evaluation_warnings;
13788 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13789 /*function_p=*/false,
13790 /*integral_constant_expression_p=*/false);
13791 --cp_unevaluated_operand;
13792 --c_inhibit_evaluation_warnings;
13793 RETURN (objc_build_encode_expr (op1));
13796 case NOEXCEPT_EXPR:
13797 op1 = TREE_OPERAND (t, 0);
13798 ++cp_unevaluated_operand;
13799 ++c_inhibit_evaluation_warnings;
13800 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
13801 /*function_p=*/false,
13802 /*integral_constant_expression_p=*/false);
13803 --cp_unevaluated_operand;
13804 --c_inhibit_evaluation_warnings;
13805 RETURN (finish_noexcept_expr (op1, complain));
13809 tree r = build_x_modify_expr
13810 (EXPR_LOCATION (t),
13811 RECUR (TREE_OPERAND (t, 0)),
13812 TREE_CODE (TREE_OPERAND (t, 1)),
13813 RECUR (TREE_OPERAND (t, 2)),
13814 complain|decltype_flag);
13815 /* TREE_NO_WARNING must be set if either the expression was
13816 parenthesized or it uses an operator such as >>= rather
13817 than plain assignment. In the former case, it was already
13818 set and must be copied. In the latter case,
13819 build_x_modify_expr sets it and it must not be reset
13821 if (TREE_NO_WARNING (t))
13822 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
13827 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
13828 args, complain, in_decl);
13829 /* Remember that there was a reference to this entity. */
13832 RETURN (build_x_arrow (input_location, op1, complain));
13836 tree placement = RECUR (TREE_OPERAND (t, 0));
13837 tree init = RECUR (TREE_OPERAND (t, 3));
13838 vec<tree, va_gc> *placement_vec;
13839 vec<tree, va_gc> *init_vec;
13842 if (placement == NULL_TREE)
13843 placement_vec = NULL;
13846 placement_vec = make_tree_vector ();
13847 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
13848 vec_safe_push (placement_vec, TREE_VALUE (placement));
13851 /* If there was an initializer in the original tree, but it
13852 instantiated to an empty list, then we should pass a
13853 non-NULL empty vector to tell build_new that it was an
13854 empty initializer() rather than no initializer. This can
13855 only happen when the initializer is a pack expansion whose
13856 parameter packs are of length zero. */
13857 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
13861 init_vec = make_tree_vector ();
13862 if (init == void_zero_node)
13863 gcc_assert (init_vec != NULL);
13866 for (; init != NULL_TREE; init = TREE_CHAIN (init))
13867 vec_safe_push (init_vec, TREE_VALUE (init));
13871 ret = build_new (&placement_vec,
13872 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl),
13873 RECUR (TREE_OPERAND (t, 2)),
13875 NEW_EXPR_USE_GLOBAL (t),
13878 if (placement_vec != NULL)
13879 release_tree_vector (placement_vec);
13880 if (init_vec != NULL)
13881 release_tree_vector (init_vec);
13887 RETURN (delete_sanity
13888 (RECUR (TREE_OPERAND (t, 0)),
13889 RECUR (TREE_OPERAND (t, 1)),
13890 DELETE_EXPR_USE_VEC (t),
13891 DELETE_EXPR_USE_GLOBAL (t),
13894 case COMPOUND_EXPR:
13896 tree op0 = tsubst_copy_and_build (TREE_OPERAND (t, 0), args,
13897 complain & ~tf_decltype, in_decl,
13898 /*function_p=*/false,
13899 integral_constant_expression_p);
13900 RETURN (build_x_compound_expr (EXPR_LOCATION (t),
13902 RECUR (TREE_OPERAND (t, 1)),
13903 complain|decltype_flag));
13909 vec<tree, va_gc> *call_args;
13910 unsigned int nargs, i;
13915 function = CALL_EXPR_FN (t);
13916 /* When we parsed the expression, we determined whether or
13917 not Koenig lookup should be performed. */
13918 koenig_p = KOENIG_LOOKUP_P (t);
13919 if (TREE_CODE (function) == SCOPE_REF)
13921 qualified_p = true;
13922 function = tsubst_qualified_id (function, args, complain, in_decl,
13924 /*address_p=*/false);
13926 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE)
13928 /* Do nothing; calling tsubst_copy_and_build on an identifier
13929 would incorrectly perform unqualified lookup again.
13931 Note that we can also have an IDENTIFIER_NODE if the earlier
13932 unqualified lookup found a member function; in that case
13933 koenig_p will be false and we do want to do the lookup
13934 again to find the instantiated member function.
13936 FIXME but doing that causes c++/15272, so we need to stop
13937 using IDENTIFIER_NODE in that situation. */
13938 qualified_p = false;
13942 if (TREE_CODE (function) == COMPONENT_REF)
13944 tree op = TREE_OPERAND (function, 1);
13946 qualified_p = (TREE_CODE (op) == SCOPE_REF
13947 || (BASELINK_P (op)
13948 && BASELINK_QUALIFIED_P (op)));
13951 qualified_p = false;
13953 if (TREE_CODE (function) == ADDR_EXPR
13954 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
13955 /* Avoid error about taking the address of a constructor. */
13956 function = TREE_OPERAND (function, 0);
13958 function = tsubst_copy_and_build (function, args, complain,
13961 integral_constant_expression_p);
13963 if (BASELINK_P (function))
13964 qualified_p = true;
13967 nargs = call_expr_nargs (t);
13968 call_args = make_tree_vector ();
13969 for (i = 0; i < nargs; ++i)
13971 tree arg = CALL_EXPR_ARG (t, i);
13973 if (!PACK_EXPANSION_P (arg))
13974 vec_safe_push (call_args, RECUR (CALL_EXPR_ARG (t, i)));
13977 /* Expand the pack expansion and push each entry onto
13979 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
13980 if (TREE_CODE (arg) == TREE_VEC)
13982 unsigned int len, j;
13984 len = TREE_VEC_LENGTH (arg);
13985 for (j = 0; j < len; ++j)
13987 tree value = TREE_VEC_ELT (arg, j);
13988 if (value != NULL_TREE)
13989 value = convert_from_reference (value);
13990 vec_safe_push (call_args, value);
13995 /* A partial substitution. Add one entry. */
13996 vec_safe_push (call_args, arg);
14001 /* We do not perform argument-dependent lookup if normal
14002 lookup finds a non-function, in accordance with the
14003 expected resolution of DR 218. */
14005 && ((is_overloaded_fn (function)
14006 /* If lookup found a member function, the Koenig lookup is
14007 not appropriate, even if an unqualified-name was used
14008 to denote the function. */
14009 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
14010 || TREE_CODE (function) == IDENTIFIER_NODE)
14011 /* Only do this when substitution turns a dependent call
14012 into a non-dependent call. */
14013 && type_dependent_expression_p_push (t)
14014 && !any_type_dependent_arguments_p (call_args))
14015 function = perform_koenig_lookup (function, call_args, false,
14018 if (TREE_CODE (function) == IDENTIFIER_NODE
14019 && !any_type_dependent_arguments_p (call_args))
14021 if (koenig_p && (complain & tf_warning_or_error))
14023 /* For backwards compatibility and good diagnostics, try
14024 the unqualified lookup again if we aren't in SFINAE
14026 tree unq = (tsubst_copy_and_build
14027 (function, args, complain, in_decl, true,
14028 integral_constant_expression_p));
14029 if (unq == error_mark_node)
14030 RETURN (error_mark_node);
14032 if (unq != function)
14035 if (TREE_CODE (fn) == INDIRECT_REF)
14036 fn = TREE_OPERAND (fn, 0);
14037 if (TREE_CODE (fn) == COMPONENT_REF)
14038 fn = TREE_OPERAND (fn, 1);
14039 if (is_overloaded_fn (fn))
14040 fn = get_first_fn (fn);
14041 permerror (EXPR_LOC_OR_HERE (t),
14042 "%qD was not declared in this scope, "
14043 "and no declarations were found by "
14044 "argument-dependent lookup at the point "
14045 "of instantiation", function);
14047 /* Can't say anything more. */;
14048 else if (DECL_CLASS_SCOPE_P (fn))
14050 inform (EXPR_LOC_OR_HERE (t),
14051 "declarations in dependent base %qT are "
14052 "not found by unqualified lookup",
14053 DECL_CLASS_CONTEXT (fn));
14054 if (current_class_ptr)
14055 inform (EXPR_LOC_OR_HERE (t),
14056 "use %<this->%D%> instead", function);
14058 inform (EXPR_LOC_OR_HERE (t),
14059 "use %<%T::%D%> instead",
14060 current_class_name, function);
14063 inform (0, "%q+D declared here, later in the "
14064 "translation unit", fn);
14068 if (TREE_CODE (function) == IDENTIFIER_NODE)
14070 if (complain & tf_error)
14071 unqualified_name_lookup_error (function);
14072 release_tree_vector (call_args);
14073 RETURN (error_mark_node);
14077 /* Remember that there was a reference to this entity. */
14078 if (DECL_P (function))
14079 mark_used (function);
14081 /* Put back tf_decltype for the actual call. */
14082 complain |= decltype_flag;
14084 if (TREE_CODE (function) == OFFSET_REF)
14085 ret = build_offset_ref_call_from_tree (function, &call_args,
14087 else if (TREE_CODE (function) == COMPONENT_REF)
14089 tree instance = TREE_OPERAND (function, 0);
14090 tree fn = TREE_OPERAND (function, 1);
14092 if (processing_template_decl
14093 && (type_dependent_expression_p (instance)
14094 || (!BASELINK_P (fn)
14095 && TREE_CODE (fn) != FIELD_DECL)
14096 || type_dependent_expression_p (fn)
14097 || any_type_dependent_arguments_p (call_args)))
14098 ret = build_nt_call_vec (function, call_args);
14099 else if (!BASELINK_P (fn))
14100 ret = finish_call_expr (function, &call_args,
14101 /*disallow_virtual=*/false,
14102 /*koenig_p=*/false,
14105 ret = (build_new_method_call
14107 &call_args, NULL_TREE,
14108 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
14113 ret = finish_call_expr (function, &call_args,
14114 /*disallow_virtual=*/qualified_p,
14118 release_tree_vector (call_args);
14125 tree cond = RECUR (TREE_OPERAND (t, 0));
14128 if (TREE_CODE (cond) == INTEGER_CST)
14130 if (integer_zerop (cond))
14132 ++c_inhibit_evaluation_warnings;
14133 exp1 = RECUR (TREE_OPERAND (t, 1));
14134 --c_inhibit_evaluation_warnings;
14135 exp2 = RECUR (TREE_OPERAND (t, 2));
14139 exp1 = RECUR (TREE_OPERAND (t, 1));
14140 ++c_inhibit_evaluation_warnings;
14141 exp2 = RECUR (TREE_OPERAND (t, 2));
14142 --c_inhibit_evaluation_warnings;
14147 exp1 = RECUR (TREE_OPERAND (t, 1));
14148 exp2 = RECUR (TREE_OPERAND (t, 2));
14151 RETURN (build_x_conditional_expr (EXPR_LOCATION (t),
14152 cond, exp1, exp2, complain));
14155 case PSEUDO_DTOR_EXPR:
14156 RETURN (finish_pseudo_destructor_expr
14157 (RECUR (TREE_OPERAND (t, 0)),
14158 RECUR (TREE_OPERAND (t, 1)),
14159 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl)));
14163 tree purpose, value, chain;
14165 if (t == void_list_node)
14168 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
14169 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
14171 /* We have pack expansions, so expand those and
14172 create a new list out of it. */
14173 tree purposevec = NULL_TREE;
14174 tree valuevec = NULL_TREE;
14178 /* Expand the argument expressions. */
14179 if (TREE_PURPOSE (t))
14180 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
14181 complain, in_decl);
14182 if (TREE_VALUE (t))
14183 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
14184 complain, in_decl);
14186 /* Build the rest of the list. */
14187 chain = TREE_CHAIN (t);
14188 if (chain && chain != void_type_node)
14189 chain = RECUR (chain);
14191 /* Determine the number of arguments. */
14192 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
14194 len = TREE_VEC_LENGTH (purposevec);
14195 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
14197 else if (TREE_CODE (valuevec) == TREE_VEC)
14198 len = TREE_VEC_LENGTH (valuevec);
14201 /* Since we only performed a partial substitution into
14202 the argument pack, we only RETURN (a single list
14204 if (purposevec == TREE_PURPOSE (t)
14205 && valuevec == TREE_VALUE (t)
14206 && chain == TREE_CHAIN (t))
14209 RETURN (tree_cons (purposevec, valuevec, chain));
14212 /* Convert the argument vectors into a TREE_LIST */
14216 /* Grab the Ith values. */
14218 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
14221 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
14224 /* Build the list (backwards). */
14225 chain = tree_cons (purpose, value, chain);
14231 purpose = TREE_PURPOSE (t);
14233 purpose = RECUR (purpose);
14234 value = TREE_VALUE (t);
14236 value = RECUR (value);
14237 chain = TREE_CHAIN (t);
14238 if (chain && chain != void_type_node)
14239 chain = RECUR (chain);
14240 if (purpose == TREE_PURPOSE (t)
14241 && value == TREE_VALUE (t)
14242 && chain == TREE_CHAIN (t))
14244 RETURN (tree_cons (purpose, value, chain));
14247 case COMPONENT_REF:
14253 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
14254 args, complain, in_decl);
14255 /* Remember that there was a reference to this entity. */
14256 if (DECL_P (object))
14257 mark_used (object);
14258 object_type = TREE_TYPE (object);
14260 member = TREE_OPERAND (t, 1);
14261 if (BASELINK_P (member))
14262 member = tsubst_baselink (member,
14263 non_reference (TREE_TYPE (object)),
14264 args, complain, in_decl);
14266 member = tsubst_copy (member, args, complain, in_decl);
14267 if (member == error_mark_node)
14268 RETURN (error_mark_node);
14270 if (type_dependent_expression_p (object))
14271 /* We can't do much here. */;
14272 else if (!CLASS_TYPE_P (object_type))
14274 if (scalarish_type_p (object_type))
14276 tree s = NULL_TREE;
14277 tree dtor = member;
14279 if (TREE_CODE (dtor) == SCOPE_REF)
14281 s = TREE_OPERAND (dtor, 0);
14282 dtor = TREE_OPERAND (dtor, 1);
14284 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
14286 dtor = TREE_OPERAND (dtor, 0);
14288 RETURN (finish_pseudo_destructor_expr (object, s, dtor));
14292 else if (TREE_CODE (member) == SCOPE_REF
14293 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
14295 /* Lookup the template functions now that we know what the
14297 tree scope = TREE_OPERAND (member, 0);
14298 tree tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
14299 tree args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
14300 member = lookup_qualified_name (scope, tmpl,
14301 /*is_type_p=*/false,
14302 /*complain=*/false);
14303 if (BASELINK_P (member))
14305 BASELINK_FUNCTIONS (member)
14306 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
14308 member = (adjust_result_of_qualified_name_lookup
14309 (member, BINFO_TYPE (BASELINK_BINFO (member)),
14314 qualified_name_lookup_error (scope, tmpl, member,
14316 RETURN (error_mark_node);
14319 else if (TREE_CODE (member) == SCOPE_REF
14320 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
14321 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
14323 if (complain & tf_error)
14325 if (TYPE_P (TREE_OPERAND (member, 0)))
14326 error ("%qT is not a class or namespace",
14327 TREE_OPERAND (member, 0));
14329 error ("%qD is not a class or namespace",
14330 TREE_OPERAND (member, 0));
14332 RETURN (error_mark_node);
14334 else if (TREE_CODE (member) == FIELD_DECL)
14335 RETURN (finish_non_static_data_member (member, object, NULL_TREE));
14337 RETURN (finish_class_member_access_expr (object, member,
14338 /*template_p=*/false,
14343 RETURN (build_throw
14344 (RECUR (TREE_OPERAND (t, 0))));
14348 vec<constructor_elt, va_gc> *n;
14349 constructor_elt *ce;
14350 unsigned HOST_WIDE_INT idx;
14351 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
14352 bool process_index_p;
14354 bool need_copy_p = false;
14357 if (type == error_mark_node)
14358 RETURN (error_mark_node);
14360 /* digest_init will do the wrong thing if we let it. */
14361 if (type && TYPE_PTRMEMFUNC_P (type))
14364 /* We do not want to process the index of aggregate
14365 initializers as they are identifier nodes which will be
14366 looked up by digest_init. */
14367 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
14369 n = vec_safe_copy (CONSTRUCTOR_ELTS (t));
14370 newlen = vec_safe_length (n);
14371 FOR_EACH_VEC_SAFE_ELT (n, idx, ce)
14373 if (ce->index && process_index_p
14374 /* An identifier index is looked up in the type
14375 being initialized, not the current scope. */
14376 && TREE_CODE (ce->index) != IDENTIFIER_NODE)
14377 ce->index = RECUR (ce->index);
14379 if (PACK_EXPANSION_P (ce->value))
14381 /* Substitute into the pack expansion. */
14382 ce->value = tsubst_pack_expansion (ce->value, args, complain,
14385 if (ce->value == error_mark_node
14386 || PACK_EXPANSION_P (ce->value))
14388 else if (TREE_VEC_LENGTH (ce->value) == 1)
14389 /* Just move the argument into place. */
14390 ce->value = TREE_VEC_ELT (ce->value, 0);
14393 /* Update the length of the final CONSTRUCTOR
14394 arguments vector, and note that we will need to
14396 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
14397 need_copy_p = true;
14401 ce->value = RECUR (ce->value);
14406 vec<constructor_elt, va_gc> *old_n = n;
14408 vec_alloc (n, newlen);
14409 FOR_EACH_VEC_ELT (*old_n, idx, ce)
14411 if (TREE_CODE (ce->value) == TREE_VEC)
14413 int i, len = TREE_VEC_LENGTH (ce->value);
14414 for (i = 0; i < len; ++i)
14415 CONSTRUCTOR_APPEND_ELT (n, 0,
14416 TREE_VEC_ELT (ce->value, i));
14419 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
14423 r = build_constructor (init_list_type_node, n);
14424 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
14426 if (TREE_HAS_CONSTRUCTOR (t))
14427 RETURN (finish_compound_literal (type, r, complain));
14429 TREE_TYPE (r) = type;
14435 tree operand_0 = TREE_OPERAND (t, 0);
14436 if (TYPE_P (operand_0))
14438 operand_0 = tsubst (operand_0, args, complain, in_decl);
14439 RETURN (get_typeid (operand_0, complain));
14443 operand_0 = RECUR (operand_0);
14444 RETURN (build_typeid (operand_0, complain));
14455 tree r = tsubst_copy (t, args, complain, in_decl);
14457 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
14458 /* If the original type was a reference, we'll be wrapped in
14459 the appropriate INDIRECT_REF. */
14460 r = convert_from_reference (r);
14465 RETURN (build_x_va_arg (EXPR_LOCATION (t),
14466 RECUR (TREE_OPERAND (t, 0)),
14467 tsubst (TREE_TYPE (t), args, complain, in_decl)));
14469 case OFFSETOF_EXPR:
14470 RETURN (finish_offsetof (RECUR (TREE_OPERAND (t, 0))));
14474 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
14475 complain, in_decl);
14477 tree type2 = TRAIT_EXPR_TYPE2 (t);
14479 type2 = tsubst_copy (type2, args, complain, in_decl);
14481 RETURN (finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2));
14486 tree old_stmt_expr = cur_stmt_expr;
14487 tree stmt_expr = begin_stmt_expr ();
14489 cur_stmt_expr = stmt_expr;
14490 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
14491 integral_constant_expression_p);
14492 stmt_expr = finish_stmt_expr (stmt_expr, false);
14493 cur_stmt_expr = old_stmt_expr;
14495 /* If the resulting list of expression statement is empty,
14496 fold it further into void_zero_node. */
14497 if (empty_expr_stmt_p (stmt_expr))
14498 stmt_expr = void_zero_node;
14500 RETURN (stmt_expr);
14505 tree r = build_lambda_expr ();
14507 tree type = tsubst (LAMBDA_EXPR_CLOSURE (t), args, complain, NULL_TREE);
14508 LAMBDA_EXPR_CLOSURE (r) = type;
14509 CLASSTYPE_LAMBDA_EXPR (type) = r;
14511 LAMBDA_EXPR_LOCATION (r)
14512 = LAMBDA_EXPR_LOCATION (t);
14513 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r)
14514 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t);
14515 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t);
14516 LAMBDA_EXPR_DISCRIMINATOR (r)
14517 = (LAMBDA_EXPR_DISCRIMINATOR (t));
14518 /* For a function scope, we want to use tsubst so that we don't
14519 complain about referring to an auto function before its return
14520 type has been deduced. Otherwise, we want to use tsubst_copy so
14521 that we look up the existing field/parameter/variable rather
14522 than build a new one. */
14523 tree scope = LAMBDA_EXPR_EXTRA_SCOPE (t);
14524 if (scope && TREE_CODE (scope) == FUNCTION_DECL)
14525 scope = tsubst (scope, args, complain, in_decl);
14526 else if (scope && TREE_CODE (scope) == PARM_DECL)
14528 /* Look up the parameter we want directly, as tsubst_copy
14529 doesn't do what we need. */
14530 tree fn = tsubst (DECL_CONTEXT (scope), args, complain, in_decl);
14531 tree parm = FUNCTION_FIRST_USER_PARM (fn);
14532 while (DECL_PARM_INDEX (parm) != DECL_PARM_INDEX (scope))
14533 parm = DECL_CHAIN (parm);
14535 /* FIXME Work around the parm not having DECL_CONTEXT set. */
14536 if (DECL_CONTEXT (scope) == NULL_TREE)
14537 DECL_CONTEXT (scope) = fn;
14540 scope = RECUR (scope);
14541 LAMBDA_EXPR_EXTRA_SCOPE (r) = scope;
14542 LAMBDA_EXPR_RETURN_TYPE (r)
14543 = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl);
14545 gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (t) == NULL_TREE
14546 && LAMBDA_EXPR_PENDING_PROXIES (t) == NULL);
14548 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */
14549 determine_visibility (TYPE_NAME (type));
14550 /* Now that we know visibility, instantiate the type so we have a
14551 declaration of the op() for later calls to lambda_function. */
14552 complete_type (type);
14554 LAMBDA_EXPR_THIS_CAPTURE (r) = NULL_TREE;
14556 RETURN (build_lambda_object (r));
14560 /* We can get here for a constant initializer of non-dependent type.
14561 FIXME stop folding in cp_parser_initializer_clause. */
14563 tree r = get_target_expr_sfinae (RECUR (TARGET_EXPR_INITIAL (t)),
14568 case TRANSACTION_EXPR:
14569 RETURN (tsubst_expr(t, args, complain, in_decl,
14570 integral_constant_expression_p));
14573 /* Handle Objective-C++ constructs, if appropriate. */
14576 = objcp_tsubst_copy_and_build (t, args, complain,
14577 in_decl, /*function_p=*/false);
14581 RETURN (tsubst_copy (t, args, complain, in_decl));
14587 input_location = loc;
14591 /* Verify that the instantiated ARGS are valid. For type arguments,
14592 make sure that the type's linkage is ok. For non-type arguments,
14593 make sure they are constants if they are integral or enumerations.
14594 Emit an error under control of COMPLAIN, and return TRUE on error. */
14597 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
14599 if (dependent_template_arg_p (t))
14601 if (ARGUMENT_PACK_P (t))
14603 tree vec = ARGUMENT_PACK_ARGS (t);
14604 int len = TREE_VEC_LENGTH (vec);
14605 bool result = false;
14608 for (i = 0; i < len; ++i)
14609 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
14613 else if (TYPE_P (t))
14615 /* [basic.link]: A name with no linkage (notably, the name
14616 of a class or enumeration declared in a local scope)
14617 shall not be used to declare an entity with linkage.
14618 This implies that names with no linkage cannot be used as
14621 DR 757 relaxes this restriction for C++0x. */
14622 tree nt = (cxx_dialect > cxx98 ? NULL_TREE
14623 : no_linkage_check (t, /*relaxed_p=*/false));
14627 /* DR 488 makes use of a type with no linkage cause
14628 type deduction to fail. */
14629 if (complain & tf_error)
14631 if (TYPE_ANONYMOUS_P (nt))
14632 error ("%qT is/uses anonymous type", t);
14634 error ("template argument for %qD uses local type %qT",
14639 /* In order to avoid all sorts of complications, we do not
14640 allow variably-modified types as template arguments. */
14641 else if (variably_modified_type_p (t, NULL_TREE))
14643 if (complain & tf_error)
14644 error ("%qT is a variably modified type", t);
14648 /* Class template and alias template arguments should be OK. */
14649 else if (DECL_TYPE_TEMPLATE_P (t))
14651 /* A non-type argument of integral or enumerated type must be a
14653 else if (TREE_TYPE (t)
14654 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
14655 && !TREE_CONSTANT (t))
14657 if (complain & tf_error)
14658 error ("integral expression %qE is not constant", t);
14665 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
14667 int ix, len = DECL_NTPARMS (tmpl);
14668 bool result = false;
14670 for (ix = 0; ix != len; ix++)
14672 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
14675 if (result && (complain & tf_error))
14676 error (" trying to instantiate %qD", tmpl);
14680 /* We're out of SFINAE context now, so generate diagnostics for the access
14681 errors we saw earlier when instantiating D from TMPL and ARGS. */
14684 recheck_decl_substitution (tree d, tree tmpl, tree args)
14686 tree pattern = DECL_TEMPLATE_RESULT (tmpl);
14687 tree type = TREE_TYPE (pattern);
14688 location_t loc = input_location;
14690 push_access_scope (d);
14691 push_deferring_access_checks (dk_no_deferred);
14692 input_location = DECL_SOURCE_LOCATION (pattern);
14693 tsubst (type, args, tf_warning_or_error, d);
14694 input_location = loc;
14695 pop_deferring_access_checks ();
14696 pop_access_scope (d);
14699 /* Instantiate the indicated variable, function, or alias template TMPL with
14700 the template arguments in TARG_PTR. */
14703 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain)
14705 tree targ_ptr = orig_args;
14709 bool access_ok = true;
14711 if (tmpl == error_mark_node)
14712 return error_mark_node;
14714 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
14716 /* If this function is a clone, handle it specially. */
14717 if (DECL_CLONED_FUNCTION_P (tmpl))
14722 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
14723 DECL_CLONED_FUNCTION. */
14724 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
14725 targ_ptr, complain);
14726 if (spec == error_mark_node)
14727 return error_mark_node;
14729 /* Look for the clone. */
14730 FOR_EACH_CLONE (clone, spec)
14731 if (DECL_NAME (clone) == DECL_NAME (tmpl))
14733 /* We should always have found the clone by now. */
14734 gcc_unreachable ();
14738 /* Check to see if we already have this specialization. */
14739 gen_tmpl = most_general_template (tmpl);
14740 if (tmpl != gen_tmpl)
14741 /* The TMPL is a partial instantiation. To get a full set of
14742 arguments we must add the arguments used to perform the
14743 partial instantiation. */
14744 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
14747 /* It would be nice to avoid hashing here and then again in tsubst_decl,
14748 but it doesn't seem to be on the hot path. */
14749 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
14751 gcc_assert (tmpl == gen_tmpl
14752 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
14754 || fndecl == NULL_TREE);
14756 if (spec != NULL_TREE)
14758 if (FNDECL_HAS_ACCESS_ERRORS (spec))
14760 if (complain & tf_error)
14761 recheck_decl_substitution (spec, gen_tmpl, targ_ptr);
14762 return error_mark_node;
14767 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
14769 return error_mark_node;
14771 /* We are building a FUNCTION_DECL, during which the access of its
14772 parameters and return types have to be checked. However this
14773 FUNCTION_DECL which is the desired context for access checking
14774 is not built yet. We solve this chicken-and-egg problem by
14775 deferring all checks until we have the FUNCTION_DECL. */
14776 push_deferring_access_checks (dk_deferred);
14778 /* Instantiation of the function happens in the context of the function
14779 template, not the context of the overload resolution we're doing. */
14780 push_to_top_level ();
14781 /* If there are dependent arguments, e.g. because we're doing partial
14782 ordering, make sure processing_template_decl stays set. */
14783 if (uses_template_parms (targ_ptr))
14784 ++processing_template_decl;
14785 if (DECL_CLASS_SCOPE_P (gen_tmpl))
14787 tree ctx = tsubst (DECL_CONTEXT (gen_tmpl), targ_ptr,
14788 complain, gen_tmpl);
14789 push_nested_class (ctx);
14791 /* Substitute template parameters to obtain the specialization. */
14792 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
14793 targ_ptr, complain, gen_tmpl);
14794 if (DECL_CLASS_SCOPE_P (gen_tmpl))
14795 pop_nested_class ();
14796 pop_from_top_level ();
14798 if (fndecl == error_mark_node)
14800 pop_deferring_access_checks ();
14801 return error_mark_node;
14804 /* The DECL_TI_TEMPLATE should always be the immediate parent
14805 template, not the most general template. */
14806 DECL_TI_TEMPLATE (fndecl) = tmpl;
14808 /* Now we know the specialization, compute access previously
14810 push_access_scope (fndecl);
14811 if (!perform_deferred_access_checks (complain))
14813 pop_access_scope (fndecl);
14814 pop_deferring_access_checks ();
14816 /* If we've just instantiated the main entry point for a function,
14817 instantiate all the alternate entry points as well. We do this
14818 by cloning the instantiation of the main entry point, not by
14819 instantiating the template clones. */
14820 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl)))
14821 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
14825 if (!(complain & tf_error))
14827 /* Remember to reinstantiate when we're out of SFINAE so the user
14828 can see the errors. */
14829 FNDECL_HAS_ACCESS_ERRORS (fndecl) = true;
14831 return error_mark_node;
14836 /* Wrapper for instantiate_template_1. */
14839 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
14842 timevar_push (TV_TEMPLATE_INST);
14843 ret = instantiate_template_1 (tmpl, orig_args, complain);
14844 timevar_pop (TV_TEMPLATE_INST);
14848 /* Instantiate the alias template TMPL with ARGS. Also push a template
14849 instantiation level, which instantiate_template doesn't do because
14850 functions and variables have sufficient context established by the
14854 instantiate_alias_template (tree tmpl, tree args, tsubst_flags_t complain)
14856 struct pending_template *old_last_pend = last_pending_template;
14857 struct tinst_level *old_error_tinst = last_error_tinst_level;
14858 if (tmpl == error_mark_node || args == error_mark_node)
14859 return error_mark_node;
14860 tree tinst = build_tree_list (tmpl, args);
14861 if (!push_tinst_level (tinst))
14864 return error_mark_node;
14868 coerce_innermost_template_parms (DECL_TEMPLATE_PARMS (tmpl),
14869 args, tmpl, complain,
14870 /*require_all_args=*/true,
14871 /*use_default_args=*/true);
14873 tree r = instantiate_template (tmpl, args, complain);
14874 pop_tinst_level ();
14875 /* We can't free this if a pending_template entry or last_error_tinst_level
14876 is pointing at it. */
14877 if (last_pending_template == old_last_pend
14878 && last_error_tinst_level == old_error_tinst)
14884 /* PARM is a template parameter pack for FN. Returns true iff
14885 PARM is used in a deducible way in the argument list of FN. */
14888 pack_deducible_p (tree parm, tree fn)
14890 tree t = FUNCTION_FIRST_USER_PARMTYPE (fn);
14891 for (; t; t = TREE_CHAIN (t))
14893 tree type = TREE_VALUE (t);
14895 if (!PACK_EXPANSION_P (type))
14897 for (packs = PACK_EXPANSION_PARAMETER_PACKS (type);
14898 packs; packs = TREE_CHAIN (packs))
14899 if (TREE_VALUE (packs) == parm)
14901 /* The template parameter pack is used in a function parameter
14902 pack. If this is the end of the parameter list, the
14903 template parameter pack is deducible. */
14904 if (TREE_CHAIN (t) == void_list_node)
14907 /* Otherwise, not. Well, it could be deduced from
14908 a non-pack parameter, but doing so would end up with
14909 a deduction mismatch, so don't bother. */
14913 /* The template parameter pack isn't used in any function parameter
14914 packs, but it might be used deeper, e.g. tuple<Args...>. */
14918 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
14919 NARGS elements of the arguments that are being used when calling
14920 it. TARGS is a vector into which the deduced template arguments
14923 Return zero for success, 2 for an incomplete match that doesn't resolve
14924 all the types, and 1 for complete failure. An error message will be
14925 printed only for an incomplete match.
14927 If FN is a conversion operator, or we are trying to produce a specific
14928 specialization, RETURN_TYPE is the return type desired.
14930 The EXPLICIT_TARGS are explicit template arguments provided via a
14933 The parameter STRICT is one of:
14936 We are deducing arguments for a function call, as in
14937 [temp.deduct.call].
14940 We are deducing arguments for a conversion function, as in
14941 [temp.deduct.conv].
14944 We are deducing arguments when doing an explicit instantiation
14945 as in [temp.explicit], when determining an explicit specialization
14946 as in [temp.expl.spec], or when taking the address of a function
14947 template, as in [temp.deduct.funcaddr]. */
14950 fn_type_unification (tree fn,
14951 tree explicit_targs,
14954 unsigned int nargs,
14956 unification_kind_t strict,
14962 tree decl = NULL_TREE;
14963 tsubst_flags_t complain = (explain_p ? tf_warning_or_error : tf_none);
14965 static int deduction_depth;
14966 struct pending_template *old_last_pend = last_pending_template;
14967 struct tinst_level *old_error_tinst = last_error_tinst_level;
14968 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
14970 tree r = error_mark_node;
14972 /* In C++0x, it's possible to have a function template whose type depends
14973 on itself recursively. This is most obvious with decltype, but can also
14974 occur with enumeration scope (c++/48969). So we need to catch infinite
14975 recursion and reject the substitution at deduction time; this function
14976 will return error_mark_node for any repeated substitution.
14978 This also catches excessive recursion such as when f<N> depends on
14979 f<N-1> across all integers, and returns error_mark_node for all the
14980 substitutions back up to the initial one.
14982 This is, of course, not reentrant. */
14983 if (excessive_deduction_depth)
14984 return error_mark_node;
14985 tinst = build_tree_list (fn, NULL_TREE);
14988 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
14990 fntype = TREE_TYPE (fn);
14991 if (explicit_targs)
14995 The specified template arguments must match the template
14996 parameters in kind (i.e., type, nontype, template), and there
14997 must not be more arguments than there are parameters;
14998 otherwise type deduction fails.
15000 Nontype arguments must match the types of the corresponding
15001 nontype template parameters, or must be convertible to the
15002 types of the corresponding nontype parameters as specified in
15003 _temp.arg.nontype_, otherwise type deduction fails.
15005 All references in the function type of the function template
15006 to the corresponding template parameters are replaced by the
15007 specified template argument values. If a substitution in a
15008 template parameter or in the function type of the function
15009 template results in an invalid type, type deduction fails. */
15010 int i, len = TREE_VEC_LENGTH (tparms);
15011 location_t loc = input_location;
15012 bool incomplete = false;
15014 /* Adjust any explicit template arguments before entering the
15015 substitution context. */
15017 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE,
15019 /*require_all_args=*/false,
15020 /*use_default_args=*/false));
15021 if (explicit_targs == error_mark_node)
15024 /* Substitute the explicit args into the function type. This is
15025 necessary so that, for instance, explicitly declared function
15026 arguments can match null pointed constants. If we were given
15027 an incomplete set of explicit args, we must not do semantic
15028 processing during substitution as we could create partial
15030 for (i = 0; i < len; i++)
15032 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
15033 bool parameter_pack = false;
15034 tree targ = TREE_VEC_ELT (explicit_targs, i);
15036 /* Dig out the actual parm. */
15037 if (TREE_CODE (parm) == TYPE_DECL
15038 || TREE_CODE (parm) == TEMPLATE_DECL)
15040 parm = TREE_TYPE (parm);
15041 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
15043 else if (TREE_CODE (parm) == PARM_DECL)
15045 parm = DECL_INITIAL (parm);
15046 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
15049 if (!parameter_pack && targ == NULL_TREE)
15050 /* No explicit argument for this template parameter. */
15053 if (parameter_pack && pack_deducible_p (parm, fn))
15055 /* Mark the argument pack as "incomplete". We could
15056 still deduce more arguments during unification.
15057 We remove this mark in type_unification_real. */
15060 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
15061 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
15062 = ARGUMENT_PACK_ARGS (targ);
15065 /* We have some incomplete argument packs. */
15070 TREE_VALUE (tinst) = explicit_targs;
15071 if (!push_tinst_level (tinst))
15073 excessive_deduction_depth = true;
15076 processing_template_decl += incomplete;
15077 input_location = DECL_SOURCE_LOCATION (fn);
15078 /* Ignore any access checks; we'll see them again in
15079 instantiate_template and they might have the wrong
15080 access path at this point. */
15081 push_deferring_access_checks (dk_deferred);
15082 fntype = tsubst (TREE_TYPE (fn), explicit_targs,
15083 complain | tf_partial, NULL_TREE);
15084 pop_deferring_access_checks ();
15085 input_location = loc;
15086 processing_template_decl -= incomplete;
15087 pop_tinst_level ();
15089 if (fntype == error_mark_node)
15092 /* Place the explicitly specified arguments in TARGS. */
15093 for (i = NUM_TMPL_ARGS (explicit_targs); i--;)
15094 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (explicit_targs, i);
15097 /* Never do unification on the 'this' parameter. */
15098 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
15104 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
15105 new_args = XALLOCAVEC (tree, nargs + 1);
15106 new_args[0] = return_type;
15107 memcpy (new_args + 1, args, nargs * sizeof (tree));
15112 /* We allow incomplete unification without an error message here
15113 because the standard doesn't seem to explicitly prohibit it. Our
15114 callers must be ready to deal with unification failures in any
15117 /* type_unification_real will pass back any access checks from default
15118 template argument substitution. */
15119 vec<deferred_access_check, va_gc> *checks;
15122 ok = !type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
15123 targs, parms, args, nargs, /*subr=*/0,
15124 strict, flags, &checks, explain_p);
15129 /* Now that we have bindings for all of the template arguments,
15130 ensure that the arguments deduced for the template template
15131 parameters have compatible template parameter lists. We cannot
15132 check this property before we have deduced all template
15133 arguments, because the template parameter types of a template
15134 template parameter might depend on prior template parameters
15135 deduced after the template template parameter. The following
15136 ill-formed example illustrates this issue:
15138 template<typename T, template<T> class C> void f(C<5>, T);
15140 template<int N> struct X {};
15143 f(X<5>(), 5l); // error: template argument deduction fails
15146 The template parameter list of 'C' depends on the template type
15147 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
15148 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
15149 time that we deduce 'C'. */
15150 if (!template_template_parm_bindings_ok_p
15151 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
15153 unify_inconsistent_template_template_parameters (explain_p);
15157 /* All is well so far. Now, check:
15161 When all template arguments have been deduced, all uses of
15162 template parameters in nondeduced contexts are replaced with
15163 the corresponding deduced argument values. If the
15164 substitution results in an invalid type, as described above,
15165 type deduction fails. */
15166 TREE_VALUE (tinst) = targs;
15167 if (!push_tinst_level (tinst))
15169 excessive_deduction_depth = true;
15173 /* Also collect access checks from the instantiation. */
15174 reopen_deferring_access_checks (checks);
15176 decl = instantiate_template (fn, targs, complain);
15178 checks = get_deferred_access_checks ();
15179 pop_deferring_access_checks ();
15181 pop_tinst_level ();
15183 if (decl == error_mark_node)
15186 /* Now perform any access checks encountered during substitution. */
15187 push_access_scope (decl);
15188 ok = perform_access_checks (checks, complain);
15189 pop_access_scope (decl);
15193 /* If we're looking for an exact match, check that what we got
15194 is indeed an exact match. It might not be if some template
15195 parameters are used in non-deduced contexts. */
15196 if (strict == DEDUCE_EXACT)
15198 tree substed = TREE_TYPE (decl);
15202 = skip_artificial_parms_for (decl, TYPE_ARG_TYPES (substed));
15204 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
15205 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
15206 if (!same_type_p (args[i], TREE_VALUE (sarg)))
15208 unify_type_mismatch (explain_p, args[i],
15209 TREE_VALUE (sarg));
15218 if (excessive_deduction_depth)
15220 if (deduction_depth == 0)
15221 /* Reset once we're all the way out. */
15222 excessive_deduction_depth = false;
15225 /* We can't free this if a pending_template entry or last_error_tinst_level
15226 is pointing at it. */
15227 if (last_pending_template == old_last_pend
15228 && last_error_tinst_level == old_error_tinst)
15234 /* Adjust types before performing type deduction, as described in
15235 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
15236 sections are symmetric. PARM is the type of a function parameter
15237 or the return type of the conversion function. ARG is the type of
15238 the argument passed to the call, or the type of the value
15239 initialized with the result of the conversion function.
15240 ARG_EXPR is the original argument expression, which may be null. */
15243 maybe_adjust_types_for_deduction (unification_kind_t strict,
15257 /* Swap PARM and ARG throughout the remainder of this
15258 function; the handling is precisely symmetric since PARM
15259 will initialize ARG rather than vice versa. */
15267 /* Core issue #873: Do the DR606 thing (see below) for these cases,
15268 too, but here handle it by stripping the reference from PARM
15269 rather than by adding it to ARG. */
15270 if (TREE_CODE (*parm) == REFERENCE_TYPE
15271 && TYPE_REF_IS_RVALUE (*parm)
15272 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
15273 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
15274 && TREE_CODE (*arg) == REFERENCE_TYPE
15275 && !TYPE_REF_IS_RVALUE (*arg))
15276 *parm = TREE_TYPE (*parm);
15277 /* Nothing else to do in this case. */
15281 gcc_unreachable ();
15284 if (TREE_CODE (*parm) != REFERENCE_TYPE)
15286 /* [temp.deduct.call]
15288 If P is not a reference type:
15290 --If A is an array type, the pointer type produced by the
15291 array-to-pointer standard conversion (_conv.array_) is
15292 used in place of A for type deduction; otherwise,
15294 --If A is a function type, the pointer type produced by
15295 the function-to-pointer standard conversion
15296 (_conv.func_) is used in place of A for type deduction;
15299 --If A is a cv-qualified type, the top level
15300 cv-qualifiers of A's type are ignored for type
15302 if (TREE_CODE (*arg) == ARRAY_TYPE)
15303 *arg = build_pointer_type (TREE_TYPE (*arg));
15304 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
15305 *arg = build_pointer_type (*arg);
15307 *arg = TYPE_MAIN_VARIANT (*arg);
15310 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
15311 of the form T&&, where T is a template parameter, and the argument
15312 is an lvalue, T is deduced as A& */
15313 if (TREE_CODE (*parm) == REFERENCE_TYPE
15314 && TYPE_REF_IS_RVALUE (*parm)
15315 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
15316 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
15317 && (arg_expr ? real_lvalue_p (arg_expr)
15318 /* try_one_overload doesn't provide an arg_expr, but
15319 functions are always lvalues. */
15320 : TREE_CODE (*arg) == FUNCTION_TYPE))
15321 *arg = build_reference_type (*arg);
15323 /* [temp.deduct.call]
15325 If P is a cv-qualified type, the top level cv-qualifiers
15326 of P's type are ignored for type deduction. If P is a
15327 reference type, the type referred to by P is used for
15329 *parm = TYPE_MAIN_VARIANT (*parm);
15330 if (TREE_CODE (*parm) == REFERENCE_TYPE)
15332 *parm = TREE_TYPE (*parm);
15333 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
15336 /* DR 322. For conversion deduction, remove a reference type on parm
15337 too (which has been swapped into ARG). */
15338 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
15339 *arg = TREE_TYPE (*arg);
15344 /* Subroutine of unify_one_argument. PARM is a function parameter of a
15345 template which does contain any deducible template parameters; check if
15346 ARG is a suitable match for it. STRICT, FLAGS and EXPLAIN_P are as in
15347 unify_one_argument. */
15350 check_non_deducible_conversion (tree parm, tree arg, int strict,
15351 int flags, bool explain_p)
15356 type = TREE_TYPE (arg);
15360 if (same_type_p (parm, type))
15361 return unify_success (explain_p);
15363 if (strict == DEDUCE_CONV)
15365 if (can_convert_arg (type, parm, NULL_TREE, flags,
15366 explain_p ? tf_warning_or_error : tf_none))
15367 return unify_success (explain_p);
15369 else if (strict != DEDUCE_EXACT)
15371 if (can_convert_arg (parm, type,
15372 TYPE_P (arg) ? NULL_TREE : arg,
15373 flags, explain_p ? tf_warning_or_error : tf_none))
15374 return unify_success (explain_p);
15377 if (strict == DEDUCE_EXACT)
15378 return unify_type_mismatch (explain_p, parm, arg);
15380 return unify_arg_conversion (explain_p, parm, type, arg);
15383 /* Subroutine of type_unification_real and unify_pack_expansion to
15384 handle unification of a single P/A pair. Parameters are as
15385 for those functions. */
15388 unify_one_argument (tree tparms, tree targs, tree parm, tree arg,
15389 int subr, unification_kind_t strict, int flags,
15392 tree arg_expr = NULL_TREE;
15395 if (arg == error_mark_node || parm == error_mark_node)
15396 return unify_invalid (explain_p);
15397 if (arg == unknown_type_node)
15398 /* We can't deduce anything from this, but we might get all the
15399 template args from other function args. */
15400 return unify_success (explain_p);
15402 /* FIXME uses_deducible_template_parms */
15403 if (TYPE_P (parm) && !uses_template_parms (parm))
15404 return check_non_deducible_conversion (parm, arg, strict, flags,
15410 arg_strict = (UNIFY_ALLOW_OUTER_LEVEL
15411 | UNIFY_ALLOW_MORE_CV_QUAL
15412 | UNIFY_ALLOW_DERIVED);
15416 arg_strict = UNIFY_ALLOW_LESS_CV_QUAL;
15420 arg_strict = UNIFY_ALLOW_NONE;
15424 gcc_unreachable ();
15427 /* We only do these transformations if this is the top-level
15428 parameter_type_list in a call or declaration matching; in other
15429 situations (nested function declarators, template argument lists) we
15430 won't be comparing a type to an expression, and we don't do any type
15436 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
15437 if (type_unknown_p (arg))
15439 /* [temp.deduct.type] A template-argument can be
15440 deduced from a pointer to function or pointer
15441 to member function argument if the set of
15442 overloaded functions does not contain function
15443 templates and at most one of a set of
15444 overloaded functions provides a unique
15447 if (resolve_overloaded_unification
15448 (tparms, targs, parm, arg, strict,
15449 arg_strict, explain_p))
15450 return unify_success (explain_p);
15451 return unify_overload_resolution_failure (explain_p, arg);
15455 arg = unlowered_expr_type (arg);
15456 if (arg == error_mark_node)
15457 return unify_invalid (explain_p);
15461 maybe_adjust_types_for_deduction (strict, &parm, &arg, arg_expr);
15464 gcc_assert ((TYPE_P (parm) || TREE_CODE (parm) == TEMPLATE_DECL)
15465 == (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL));
15467 /* For deduction from an init-list we need the actual list. */
15468 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr))
15470 return unify (tparms, targs, parm, arg, arg_strict, explain_p);
15473 /* Most parms like fn_type_unification.
15475 If SUBR is 1, we're being called recursively (to unify the
15476 arguments of a function or method parameter of a function
15479 CHECKS is a pointer to a vector of access checks encountered while
15480 substituting default template arguments. */
15483 type_unification_real (tree tparms,
15487 unsigned int xnargs,
15489 unification_kind_t strict,
15491 vec<deferred_access_check, va_gc> **checks,
15496 int ntparms = TREE_VEC_LENGTH (tparms);
15497 int saw_undeduced = 0;
15500 unsigned int nargs;
15503 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
15504 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
15505 gcc_assert (ntparms > 0);
15507 /* Reset the number of non-defaulted template arguments contained
15509 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE;
15517 while (parms && parms != void_list_node
15520 parm = TREE_VALUE (parms);
15522 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION
15523 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node))
15524 /* For a function parameter pack that occurs at the end of the
15525 parameter-declaration-list, the type A of each remaining
15526 argument of the call is compared with the type P of the
15527 declarator-id of the function parameter pack. */
15530 parms = TREE_CHAIN (parms);
15532 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION)
15533 /* For a function parameter pack that does not occur at the
15534 end of the parameter-declaration-list, the type of the
15535 parameter pack is a non-deduced context. */
15541 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
15547 && parms != void_list_node
15548 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
15550 /* Unify the remaining arguments with the pack expansion type. */
15552 tree parmvec = make_tree_vec (1);
15554 /* Allocate a TREE_VEC and copy in all of the arguments */
15555 argvec = make_tree_vec (nargs - ia);
15556 for (i = 0; ia < nargs; ++ia, ++i)
15557 TREE_VEC_ELT (argvec, i) = args[ia];
15559 /* Copy the parameter into parmvec. */
15560 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
15561 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
15562 /*subr=*/subr, explain_p))
15565 /* Advance to the end of the list of parameters. */
15566 parms = TREE_CHAIN (parms);
15569 /* Fail if we've reached the end of the parm list, and more args
15570 are present, and the parm list isn't variadic. */
15571 if (ia < nargs && parms == void_list_node)
15572 return unify_too_many_arguments (explain_p, nargs, ia);
15573 /* Fail if parms are left and they don't have default values. */
15574 if (parms && parms != void_list_node
15575 && TREE_PURPOSE (parms) == NULL_TREE)
15577 unsigned int count = nargs;
15579 while (p && p != void_list_node)
15582 p = TREE_CHAIN (p);
15584 return unify_too_few_arguments (explain_p, ia, count);
15589 tsubst_flags_t complain = (explain_p
15590 ? tf_warning_or_error
15593 for (i = 0; i < ntparms; i++)
15595 tree targ = TREE_VEC_ELT (targs, i);
15596 tree tparm = TREE_VEC_ELT (tparms, i);
15598 /* Clear the "incomplete" flags on all argument packs now so that
15599 substituting them into later default arguments works. */
15600 if (targ && ARGUMENT_PACK_P (targ))
15602 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0;
15603 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE;
15606 if (targ || tparm == error_mark_node)
15608 tparm = TREE_VALUE (tparm);
15610 /* If this is an undeduced nontype parameter that depends on
15611 a type parameter, try another pass; its type may have been
15612 deduced from a later argument than the one from which
15613 this parameter can be deduced. */
15614 if (TREE_CODE (tparm) == PARM_DECL
15615 && uses_template_parms (TREE_TYPE (tparm))
15616 && !saw_undeduced++)
15619 /* Core issue #226 (C++0x) [temp.deduct]:
15621 If a template argument has not been deduced, its
15622 default template argument, if any, is used.
15624 When we are in C++98 mode, TREE_PURPOSE will either
15625 be NULL_TREE or ERROR_MARK_NODE, so we do not need
15626 to explicitly check cxx_dialect here. */
15627 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
15629 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
15630 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i));
15631 reopen_deferring_access_checks (*checks);
15632 location_t save_loc = input_location;
15634 input_location = DECL_SOURCE_LOCATION (parm);
15635 arg = tsubst_template_arg (arg, targs, complain, NULL_TREE);
15636 arg = convert_template_argument (parm, arg, targs, complain,
15638 input_location = save_loc;
15639 *checks = get_deferred_access_checks ();
15640 pop_deferring_access_checks ();
15641 if (arg == error_mark_node)
15645 TREE_VEC_ELT (targs, i) = arg;
15646 /* The position of the first default template argument,
15647 is also the number of non-defaulted arguments in TARGS.
15649 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15650 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i);
15655 /* If the type parameter is a parameter pack, then it will
15656 be deduced to an empty parameter pack. */
15657 if (template_parameter_pack_p (tparm))
15661 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
15663 arg = make_node (NONTYPE_ARGUMENT_PACK);
15664 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
15665 TREE_CONSTANT (arg) = 1;
15668 arg = cxx_make_type (TYPE_ARGUMENT_PACK);
15670 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
15672 TREE_VEC_ELT (targs, i) = arg;
15676 return unify_parameter_deduction_failure (explain_p, tparm);
15679 #ifdef ENABLE_CHECKING
15680 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs))
15681 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs));
15684 return unify_success (explain_p);
15687 /* Subroutine of type_unification_real. Args are like the variables
15688 at the call site. ARG is an overloaded function (or template-id);
15689 we try deducing template args from each of the overloads, and if
15690 only one succeeds, we go with that. Modifies TARGS and returns
15691 true on success. */
15694 resolve_overloaded_unification (tree tparms,
15698 unification_kind_t strict,
15702 tree tempargs = copy_node (targs);
15704 tree goodfn = NULL_TREE;
15707 if (TREE_CODE (arg) == ADDR_EXPR)
15709 arg = TREE_OPERAND (arg, 0);
15715 if (TREE_CODE (arg) == COMPONENT_REF)
15716 /* Handle `&x' where `x' is some static or non-static member
15718 arg = TREE_OPERAND (arg, 1);
15720 if (TREE_CODE (arg) == OFFSET_REF)
15721 arg = TREE_OPERAND (arg, 1);
15723 /* Strip baselink information. */
15724 if (BASELINK_P (arg))
15725 arg = BASELINK_FUNCTIONS (arg);
15727 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
15729 /* If we got some explicit template args, we need to plug them into
15730 the affected templates before we try to unify, in case the
15731 explicit args will completely resolve the templates in question. */
15734 tree expl_subargs = TREE_OPERAND (arg, 1);
15735 arg = TREE_OPERAND (arg, 0);
15737 for (; arg; arg = OVL_NEXT (arg))
15739 tree fn = OVL_CURRENT (arg);
15740 tree subargs, elem;
15742 if (TREE_CODE (fn) != TEMPLATE_DECL)
15745 subargs = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
15746 expl_subargs, NULL_TREE, tf_none,
15747 /*require_all_args=*/true,
15748 /*use_default_args=*/true);
15749 if (subargs != error_mark_node
15750 && !any_dependent_template_arguments_p (subargs))
15752 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
15753 if (try_one_overload (tparms, targs, tempargs, parm,
15754 elem, strict, sub_strict, addr_p, explain_p)
15755 && (!goodfn || !same_type_p (goodfn, elem)))
15764 /* If no templates (or more than one) are fully resolved by the
15765 explicit arguments, this template-id is a non-deduced context; it
15766 could still be OK if we deduce all template arguments for the
15767 enclosing call through other arguments. */
15771 else if (TREE_CODE (arg) != OVERLOAD
15772 && TREE_CODE (arg) != FUNCTION_DECL)
15773 /* If ARG is, for example, "(0, &f)" then its type will be unknown
15774 -- but the deduction does not succeed because the expression is
15775 not just the function on its own. */
15778 for (; arg; arg = OVL_NEXT (arg))
15779 if (try_one_overload (tparms, targs, tempargs, parm,
15780 TREE_TYPE (OVL_CURRENT (arg)),
15781 strict, sub_strict, addr_p, explain_p)
15782 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
15784 goodfn = OVL_CURRENT (arg);
15788 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15789 to function or pointer to member function argument if the set of
15790 overloaded functions does not contain function templates and at most
15791 one of a set of overloaded functions provides a unique match.
15793 So if we found multiple possibilities, we return success but don't
15794 deduce anything. */
15798 int i = TREE_VEC_LENGTH (targs);
15800 if (TREE_VEC_ELT (tempargs, i))
15801 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
15809 /* Core DR 115: In contexts where deduction is done and fails, or in
15810 contexts where deduction is not done, if a template argument list is
15811 specified and it, along with any default template arguments, identifies
15812 a single function template specialization, then the template-id is an
15813 lvalue for the function template specialization. */
15816 resolve_nondeduced_context (tree orig_expr)
15818 tree expr, offset, baselink;
15821 if (!type_unknown_p (orig_expr))
15826 offset = NULL_TREE;
15827 baselink = NULL_TREE;
15829 if (TREE_CODE (expr) == ADDR_EXPR)
15831 expr = TREE_OPERAND (expr, 0);
15834 if (TREE_CODE (expr) == OFFSET_REF)
15837 expr = TREE_OPERAND (expr, 1);
15839 if (BASELINK_P (expr))
15842 expr = BASELINK_FUNCTIONS (expr);
15845 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR)
15848 tree goodfn = NULL_TREE;
15850 /* If we got some explicit template args, we need to plug them into
15851 the affected templates before we try to unify, in case the
15852 explicit args will completely resolve the templates in question. */
15854 tree expl_subargs = TREE_OPERAND (expr, 1);
15855 tree arg = TREE_OPERAND (expr, 0);
15856 tree badfn = NULL_TREE;
15857 tree badargs = NULL_TREE;
15859 for (; arg; arg = OVL_NEXT (arg))
15861 tree fn = OVL_CURRENT (arg);
15862 tree subargs, elem;
15864 if (TREE_CODE (fn) != TEMPLATE_DECL)
15867 subargs = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
15868 expl_subargs, NULL_TREE, tf_none,
15869 /*require_all_args=*/true,
15870 /*use_default_args=*/true);
15871 if (subargs != error_mark_node
15872 && !any_dependent_template_arguments_p (subargs))
15874 elem = instantiate_template (fn, subargs, tf_none);
15875 if (elem == error_mark_node)
15880 else if (elem && (!goodfn || !decls_match (goodfn, elem)))
15889 mark_used (goodfn);
15892 expr = build_baselink (BASELINK_BINFO (baselink),
15893 BASELINK_ACCESS_BINFO (baselink),
15894 expr, BASELINK_OPTYPE (baselink));
15898 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0)));
15899 expr = build_offset_ref (base, expr, addr, tf_warning_or_error);
15902 expr = cp_build_addr_expr (expr, tf_warning_or_error);
15905 else if (good == 0 && badargs)
15906 /* There were no good options and at least one bad one, so let the
15907 user know what the problem is. */
15908 instantiate_template (badfn, badargs, tf_warning_or_error);
15913 /* Subroutine of resolve_overloaded_unification; does deduction for a single
15914 overload. Fills TARGS with any deduced arguments, or error_mark_node if
15915 different overloads deduce different arguments for a given parm.
15916 ADDR_P is true if the expression for which deduction is being
15917 performed was of the form "& fn" rather than simply "fn".
15919 Returns 1 on success. */
15922 try_one_overload (tree tparms,
15927 unification_kind_t strict,
15936 if (arg == error_mark_node)
15939 /* [temp.deduct.type] A template-argument can be deduced from a pointer
15940 to function or pointer to member function argument if the set of
15941 overloaded functions does not contain function templates and at most
15942 one of a set of overloaded functions provides a unique match.
15944 So if this is a template, just return success. */
15946 if (uses_template_parms (arg))
15949 if (TREE_CODE (arg) == METHOD_TYPE)
15950 arg = build_ptrmemfunc_type (build_pointer_type (arg));
15952 arg = build_pointer_type (arg);
15954 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
15956 /* We don't copy orig_targs for this because if we have already deduced
15957 some template args from previous args, unify would complain when we
15958 try to deduce a template parameter for the same argument, even though
15959 there isn't really a conflict. */
15960 nargs = TREE_VEC_LENGTH (targs);
15961 tempargs = make_tree_vec (nargs);
15963 if (unify (tparms, tempargs, parm, arg, sub_strict, explain_p))
15966 /* First make sure we didn't deduce anything that conflicts with
15967 explicitly specified args. */
15968 for (i = nargs; i--; )
15970 tree elt = TREE_VEC_ELT (tempargs, i);
15971 tree oldelt = TREE_VEC_ELT (orig_targs, i);
15975 else if (uses_template_parms (elt))
15976 /* Since we're unifying against ourselves, we will fill in
15977 template args used in the function parm list with our own
15978 template parms. Discard them. */
15979 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
15980 else if (oldelt && !template_args_equal (oldelt, elt))
15984 for (i = nargs; i--; )
15986 tree elt = TREE_VEC_ELT (tempargs, i);
15989 TREE_VEC_ELT (targs, i) = elt;
15995 /* PARM is a template class (perhaps with unbound template
15996 parameters). ARG is a fully instantiated type. If ARG can be
15997 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
15998 TARGS are as for unify. */
16001 try_class_unification (tree tparms, tree targs, tree parm, tree arg,
16004 tree copy_of_targs;
16006 if (!CLASSTYPE_TEMPLATE_INFO (arg)
16007 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
16008 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
16011 /* We need to make a new template argument vector for the call to
16012 unify. If we used TARGS, we'd clutter it up with the result of
16013 the attempted unification, even if this class didn't work out.
16014 We also don't want to commit ourselves to all the unifications
16015 we've already done, since unification is supposed to be done on
16016 an argument-by-argument basis. In other words, consider the
16017 following pathological case:
16019 template <int I, int J, int K>
16022 template <int I, int J>
16023 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
16025 template <int I, int J, int K>
16026 void f(S<I, J, K>, S<I, I, I>);
16035 Now, by the time we consider the unification involving `s2', we
16036 already know that we must have `f<0, 0, 0>'. But, even though
16037 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
16038 because there are two ways to unify base classes of S<0, 1, 2>
16039 with S<I, I, I>. If we kept the already deduced knowledge, we
16040 would reject the possibility I=1. */
16041 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
16043 /* If unification failed, we're done. */
16044 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
16045 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE, explain_p))
16051 /* Given a template type PARM and a class type ARG, find the unique
16052 base type in ARG that is an instance of PARM. We do not examine
16053 ARG itself; only its base-classes. If there is not exactly one
16054 appropriate base class, return NULL_TREE. PARM may be the type of
16055 a partial specialization, as well as a plain template type. Used
16058 static enum template_base_result
16059 get_template_base (tree tparms, tree targs, tree parm, tree arg,
16060 bool explain_p, tree *result)
16062 tree rval = NULL_TREE;
16065 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
16067 binfo = TYPE_BINFO (complete_type (arg));
16070 /* The type could not be completed. */
16071 *result = NULL_TREE;
16072 return tbr_incomplete_type;
16075 /* Walk in inheritance graph order. The search order is not
16076 important, and this avoids multiple walks of virtual bases. */
16077 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
16079 tree r = try_class_unification (tparms, targs, parm,
16080 BINFO_TYPE (binfo), explain_p);
16084 /* If there is more than one satisfactory baseclass, then:
16088 If they yield more than one possible deduced A, the type
16092 if (rval && !same_type_p (r, rval))
16094 *result = NULL_TREE;
16095 return tbr_ambiguous_baseclass;
16103 return tbr_success;
16106 /* Returns the level of DECL, which declares a template parameter. */
16109 template_decl_level (tree decl)
16111 switch (TREE_CODE (decl))
16114 case TEMPLATE_DECL:
16115 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
16118 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
16121 gcc_unreachable ();
16126 /* Decide whether ARG can be unified with PARM, considering only the
16127 cv-qualifiers of each type, given STRICT as documented for unify.
16128 Returns nonzero iff the unification is OK on that basis. */
16131 check_cv_quals_for_unify (int strict, tree arg, tree parm)
16133 int arg_quals = cp_type_quals (arg);
16134 int parm_quals = cp_type_quals (parm);
16136 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16137 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
16139 /* Although a CVR qualifier is ignored when being applied to a
16140 substituted template parameter ([8.3.2]/1 for example), that
16141 does not allow us to unify "const T" with "int&" because both
16142 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type].
16143 It is ok when we're allowing additional CV qualifiers
16144 at the outer level [14.8.2.1]/3,1st bullet. */
16145 if ((TREE_CODE (arg) == REFERENCE_TYPE
16146 || TREE_CODE (arg) == FUNCTION_TYPE
16147 || TREE_CODE (arg) == METHOD_TYPE)
16148 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
16151 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
16152 && (parm_quals & TYPE_QUAL_RESTRICT))
16156 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
16157 && (arg_quals & parm_quals) != parm_quals)
16160 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
16161 && (parm_quals & arg_quals) != arg_quals)
16167 /* Determines the LEVEL and INDEX for the template parameter PARM. */
16169 template_parm_level_and_index (tree parm, int* level, int* index)
16171 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16172 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16173 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16175 *index = TEMPLATE_TYPE_IDX (parm);
16176 *level = TEMPLATE_TYPE_LEVEL (parm);
16180 *index = TEMPLATE_PARM_IDX (parm);
16181 *level = TEMPLATE_PARM_LEVEL (parm);
16185 #define RECUR_AND_CHECK_FAILURE(TP, TA, P, A, S, EP) \
16187 if (unify (TP, TA, P, A, S, EP)) \
16191 /* Unifies the remaining arguments in PACKED_ARGS with the pack
16192 expansion at the end of PACKED_PARMS. Returns 0 if the type
16193 deduction succeeds, 1 otherwise. STRICT is the same as in
16194 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
16195 call argument list. We'll need to adjust the arguments to make them
16196 types. SUBR tells us if this is from a recursive call to
16197 type_unification_real, or for comparing two template argument
16201 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
16202 tree packed_args, unification_kind_t strict,
16203 bool subr, bool explain_p)
16206 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
16207 tree pattern = PACK_EXPANSION_PATTERN (parm);
16208 tree pack, packs = NULL_TREE;
16209 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
16210 int len = TREE_VEC_LENGTH (packed_args);
16212 /* Determine the parameter packs we will be deducing from the
16213 pattern, and record their current deductions. */
16214 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
16215 pack; pack = TREE_CHAIN (pack))
16217 tree parm_pack = TREE_VALUE (pack);
16220 /* Determine the index and level of this parameter pack. */
16221 template_parm_level_and_index (parm_pack, &level, &idx);
16223 /* Keep track of the parameter packs and their corresponding
16225 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
16226 TREE_TYPE (packs) = make_tree_vec (len - start);
16229 /* Loop through all of the arguments that have not yet been
16230 unified and unify each with the pattern. */
16231 for (i = start; i < len; i++)
16234 bool any_explicit = false;
16235 tree arg = TREE_VEC_ELT (packed_args, i);
16237 /* For each parameter pack, set its TMPL_ARG to either NULL_TREE
16238 or the element of its argument pack at the current index if
16239 this argument was explicitly specified. */
16240 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16244 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16247 if (TREE_VALUE (pack)
16248 && (pargs = ARGUMENT_PACK_EXPLICIT_ARGS (TREE_VALUE (pack)))
16249 && (i - start < TREE_VEC_LENGTH (pargs)))
16251 any_explicit = true;
16252 arg = TREE_VEC_ELT (pargs, i - start);
16254 TMPL_ARG (targs, level, idx) = arg;
16257 /* If we had explicit template arguments, substitute them into the
16258 pattern before deduction. */
16261 /* Some arguments might still be unspecified or dependent. */
16263 ++processing_template_decl;
16264 dependent = any_dependent_template_arguments_p (targs);
16266 --processing_template_decl;
16267 parm = tsubst (pattern, targs,
16268 explain_p ? tf_warning_or_error : tf_none,
16271 --processing_template_decl;
16272 if (parm == error_mark_node)
16278 /* Unify the pattern with the current argument. */
16279 if (unify_one_argument (tparms, targs, parm, arg, subr, strict,
16280 LOOKUP_IMPLICIT, explain_p))
16283 /* For each parameter pack, collect the deduced value. */
16284 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16287 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16289 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
16290 TMPL_ARG (targs, level, idx);
16294 /* Verify that the results of unification with the parameter packs
16295 produce results consistent with what we've seen before, and make
16296 the deduced argument packs available. */
16297 for (pack = packs; pack; pack = TREE_CHAIN (pack))
16299 tree old_pack = TREE_VALUE (pack);
16300 tree new_args = TREE_TYPE (pack);
16301 int i, len = TREE_VEC_LENGTH (new_args);
16303 bool nondeduced_p = false;
16305 /* By default keep the original deduced argument pack.
16306 If necessary, more specific code is going to update the
16307 resulting deduced argument later down in this function. */
16308 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
16309 TMPL_ARG (targs, level, idx) = old_pack;
16311 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
16312 actually deduce anything. */
16313 for (i = 0; i < len && !nondeduced_p; ++i)
16314 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
16315 nondeduced_p = true;
16319 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
16321 /* If we had fewer function args than explicit template args,
16322 just use the explicits. */
16323 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
16324 int explicit_len = TREE_VEC_LENGTH (explicit_args);
16325 if (len < explicit_len)
16326 new_args = explicit_args;
16332 /* Build the deduced *_ARGUMENT_PACK. */
16333 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
16335 result = make_node (NONTYPE_ARGUMENT_PACK);
16336 TREE_TYPE (result) =
16337 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
16338 TREE_CONSTANT (result) = 1;
16341 result = cxx_make_type (TYPE_ARGUMENT_PACK);
16343 SET_ARGUMENT_PACK_ARGS (result, new_args);
16345 /* Note the deduced argument packs for this parameter
16347 TMPL_ARG (targs, level, idx) = result;
16349 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
16350 && (ARGUMENT_PACK_ARGS (old_pack)
16351 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
16353 /* We only had the explicitly-provided arguments before, but
16354 now we have a complete set of arguments. */
16355 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
16357 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
16358 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
16359 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
16363 tree bad_old_arg = NULL_TREE, bad_new_arg = NULL_TREE;
16364 tree old_args = ARGUMENT_PACK_ARGS (old_pack);
16366 if (!comp_template_args_with_info (old_args, new_args,
16367 &bad_old_arg, &bad_new_arg))
16368 /* Inconsistent unification of this parameter pack. */
16369 return unify_parameter_pack_inconsistent (explain_p,
16375 return unify_success (explain_p);
16378 /* Deduce the value of template parameters. TPARMS is the (innermost)
16379 set of template parameters to a template. TARGS is the bindings
16380 for those template parameters, as determined thus far; TARGS may
16381 include template arguments for outer levels of template parameters
16382 as well. PARM is a parameter to a template function, or a
16383 subcomponent of that parameter; ARG is the corresponding argument.
16384 This function attempts to match PARM with ARG in a manner
16385 consistent with the existing assignments in TARGS. If more values
16386 are deduced, then TARGS is updated.
16388 Returns 0 if the type deduction succeeds, 1 otherwise. The
16389 parameter STRICT is a bitwise or of the following flags:
16392 Require an exact match between PARM and ARG.
16393 UNIFY_ALLOW_MORE_CV_QUAL:
16394 Allow the deduced ARG to be more cv-qualified (by qualification
16395 conversion) than ARG.
16396 UNIFY_ALLOW_LESS_CV_QUAL:
16397 Allow the deduced ARG to be less cv-qualified than ARG.
16398 UNIFY_ALLOW_DERIVED:
16399 Allow the deduced ARG to be a template base class of ARG,
16400 or a pointer to a template base class of the type pointed to by
16402 UNIFY_ALLOW_INTEGER:
16403 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
16404 case for more information.
16405 UNIFY_ALLOW_OUTER_LEVEL:
16406 This is the outermost level of a deduction. Used to determine validity
16407 of qualification conversions. A valid qualification conversion must
16408 have const qualified pointers leading up to the inner type which
16409 requires additional CV quals, except at the outer level, where const
16410 is not required [conv.qual]. It would be normal to set this flag in
16411 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
16412 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
16413 This is the outermost level of a deduction, and PARM can be more CV
16414 qualified at this point.
16415 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
16416 This is the outermost level of a deduction, and PARM can be less CV
16417 qualified at this point. */
16420 unify (tree tparms, tree targs, tree parm, tree arg, int strict,
16426 int strict_in = strict;
16428 /* I don't think this will do the right thing with respect to types.
16429 But the only case I've seen it in so far has been array bounds, where
16430 signedness is the only information lost, and I think that will be
16432 while (TREE_CODE (parm) == NOP_EXPR)
16433 parm = TREE_OPERAND (parm, 0);
16435 if (arg == error_mark_node)
16436 return unify_invalid (explain_p);
16437 if (arg == unknown_type_node
16438 || arg == init_list_type_node)
16439 /* We can't deduce anything from this, but we might get all the
16440 template args from other function args. */
16441 return unify_success (explain_p);
16443 /* If PARM uses template parameters, then we can't bail out here,
16444 even if ARG == PARM, since we won't record unifications for the
16445 template parameters. We might need them if we're trying to
16446 figure out which of two things is more specialized. */
16447 if (arg == parm && !uses_template_parms (parm))
16448 return unify_success (explain_p);
16450 /* Handle init lists early, so the rest of the function can assume
16451 we're dealing with a type. */
16452 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
16456 tree orig_parm = parm;
16458 /* Replace T with std::initializer_list<T> for deduction. */
16459 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16460 && flag_deduce_init_list)
16461 parm = listify (parm);
16463 if (!is_std_init_list (parm))
16464 /* We can only deduce from an initializer list argument if the
16465 parameter is std::initializer_list; otherwise this is a
16466 non-deduced context. */
16467 return unify_success (explain_p);
16469 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
16471 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
16473 int elt_strict = strict;
16475 if (elt == error_mark_node)
16476 return unify_invalid (explain_p);
16478 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
16480 tree type = TREE_TYPE (elt);
16481 /* It should only be possible to get here for a call. */
16482 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
16483 elt_strict |= maybe_adjust_types_for_deduction
16484 (DEDUCE_CALL, &elttype, &type, elt);
16488 RECUR_AND_CHECK_FAILURE (tparms, targs, elttype, elt, elt_strict,
16492 /* If the std::initializer_list<T> deduction worked, replace the
16493 deduced A with std::initializer_list<A>. */
16494 if (orig_parm != parm)
16496 idx = TEMPLATE_TYPE_IDX (orig_parm);
16497 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16498 targ = listify (targ);
16499 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ;
16501 return unify_success (explain_p);
16504 /* Immediately reject some pairs that won't unify because of
16505 cv-qualification mismatches. */
16506 if (TREE_CODE (arg) == TREE_CODE (parm)
16508 /* It is the elements of the array which hold the cv quals of an array
16509 type, and the elements might be template type parms. We'll check
16510 when we recurse. */
16511 && TREE_CODE (arg) != ARRAY_TYPE
16512 /* We check the cv-qualifiers when unifying with template type
16513 parameters below. We want to allow ARG `const T' to unify with
16514 PARM `T' for example, when computing which of two templates
16515 is more specialized, for example. */
16516 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
16517 && !check_cv_quals_for_unify (strict_in, arg, parm))
16518 return unify_cv_qual_mismatch (explain_p, parm, arg);
16520 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
16521 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
16522 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
16523 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
16524 strict &= ~UNIFY_ALLOW_DERIVED;
16525 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
16526 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
16528 switch (TREE_CODE (parm))
16530 case TYPENAME_TYPE:
16532 case UNBOUND_CLASS_TEMPLATE:
16533 /* In a type which contains a nested-name-specifier, template
16534 argument values cannot be deduced for template parameters used
16535 within the nested-name-specifier. */
16536 return unify_success (explain_p);
16538 case TEMPLATE_TYPE_PARM:
16539 case TEMPLATE_TEMPLATE_PARM:
16540 case BOUND_TEMPLATE_TEMPLATE_PARM:
16541 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16542 if (tparm == error_mark_node)
16543 return unify_invalid (explain_p);
16545 if (TEMPLATE_TYPE_LEVEL (parm)
16546 != template_decl_level (tparm))
16547 /* The PARM is not one we're trying to unify. Just check
16548 to see if it matches ARG. */
16550 if (TREE_CODE (arg) == TREE_CODE (parm)
16551 && (is_auto (parm) ? is_auto (arg)
16552 : same_type_p (parm, arg)))
16553 return unify_success (explain_p);
16555 return unify_type_mismatch (explain_p, parm, arg);
16557 idx = TEMPLATE_TYPE_IDX (parm);
16558 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16559 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
16560 if (tparm == error_mark_node)
16561 return unify_invalid (explain_p);
16563 /* Check for mixed types and values. */
16564 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
16565 && TREE_CODE (tparm) != TYPE_DECL)
16566 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16567 && TREE_CODE (tparm) != TEMPLATE_DECL))
16568 gcc_unreachable ();
16570 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16572 /* ARG must be constructed from a template class or a template
16573 template parameter. */
16574 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
16575 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
16576 return unify_template_deduction_failure (explain_p, parm, arg);
16579 tree parmvec = TYPE_TI_ARGS (parm);
16580 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
16581 tree full_argvec = add_to_template_args (targs, argvec);
16583 = DECL_INNERMOST_TEMPLATE_PARMS
16584 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
16586 int parm_variadic_p = 0;
16588 /* The resolution to DR150 makes clear that default
16589 arguments for an N-argument may not be used to bind T
16590 to a template template parameter with fewer than N
16591 parameters. It is not safe to permit the binding of
16592 default arguments as an extension, as that may change
16593 the meaning of a conforming program. Consider:
16595 struct Dense { static const unsigned int dim = 1; };
16597 template <template <typename> class View,
16599 void operator+(float, View<Block> const&);
16601 template <typename Block,
16602 unsigned int Dim = Block::dim>
16603 struct Lvalue_proxy { operator float() const; };
16607 Lvalue_proxy<Dense> p;
16612 Here, if Lvalue_proxy is permitted to bind to View, then
16613 the global operator+ will be used; if they are not, the
16614 Lvalue_proxy will be converted to float. */
16615 if (coerce_template_parms (parm_parms,
16617 TYPE_TI_TEMPLATE (parm),
16619 ? tf_warning_or_error
16621 /*require_all_args=*/true,
16622 /*use_default_args=*/false)
16623 == error_mark_node)
16626 /* Deduce arguments T, i from TT<T> or TT<i>.
16627 We check each element of PARMVEC and ARGVEC individually
16628 rather than the whole TREE_VEC since they can have
16629 different number of elements. */
16631 parmvec = expand_template_argument_pack (parmvec);
16632 argvec = expand_template_argument_pack (argvec);
16634 len = TREE_VEC_LENGTH (parmvec);
16636 /* Check if the parameters end in a pack, making them
16639 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
16640 parm_variadic_p = 1;
16642 for (i = 0; i < len - parm_variadic_p; ++i)
16643 /* If the template argument list of P contains a pack
16644 expansion that is not the last template argument, the
16645 entire template argument list is a non-deduced
16647 if (PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, i)))
16648 return unify_success (explain_p);
16650 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
16651 return unify_too_few_arguments (explain_p,
16652 TREE_VEC_LENGTH (argvec), len);
16654 for (i = 0; i < len - parm_variadic_p; ++i)
16656 RECUR_AND_CHECK_FAILURE (tparms, targs,
16657 TREE_VEC_ELT (parmvec, i),
16658 TREE_VEC_ELT (argvec, i),
16659 UNIFY_ALLOW_NONE, explain_p);
16662 if (parm_variadic_p
16663 && unify_pack_expansion (tparms, targs,
16666 /*subr=*/true, explain_p))
16669 arg = TYPE_TI_TEMPLATE (arg);
16671 /* Fall through to deduce template name. */
16674 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
16675 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
16677 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
16679 /* Simple cases: Value already set, does match or doesn't. */
16680 if (targ != NULL_TREE && template_args_equal (targ, arg))
16681 return unify_success (explain_p);
16683 return unify_inconsistency (explain_p, parm, targ, arg);
16687 /* If PARM is `const T' and ARG is only `int', we don't have
16688 a match unless we are allowing additional qualification.
16689 If ARG is `const int' and PARM is just `T' that's OK;
16690 that binds `const int' to `T'. */
16691 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
16693 return unify_cv_qual_mismatch (explain_p, parm, arg);
16695 /* Consider the case where ARG is `const volatile int' and
16696 PARM is `const T'. Then, T should be `volatile int'. */
16697 arg = cp_build_qualified_type_real
16698 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
16699 if (arg == error_mark_node)
16700 return unify_invalid (explain_p);
16702 /* Simple cases: Value already set, does match or doesn't. */
16703 if (targ != NULL_TREE && same_type_p (targ, arg))
16704 return unify_success (explain_p);
16706 return unify_inconsistency (explain_p, parm, targ, arg);
16708 /* Make sure that ARG is not a variable-sized array. (Note
16709 that were talking about variable-sized arrays (like
16710 `int[n]'), rather than arrays of unknown size (like
16711 `int[]').) We'll get very confused by such a type since
16712 the bound of the array is not constant, and therefore
16713 not mangleable. Besides, such types are not allowed in
16714 ISO C++, so we can do as we please here. We do allow
16715 them for 'auto' deduction, since that isn't ABI-exposed. */
16716 if (!is_auto (parm) && variably_modified_type_p (arg, NULL_TREE))
16717 return unify_vla_arg (explain_p, arg);
16719 /* Strip typedefs as in convert_template_argument. */
16720 arg = canonicalize_type_argument (arg, tf_none);
16723 /* If ARG is a parameter pack or an expansion, we cannot unify
16724 against it unless PARM is also a parameter pack. */
16725 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16726 && !template_parameter_pack_p (parm))
16727 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16729 /* If the argument deduction results is a METHOD_TYPE,
16730 then there is a problem.
16731 METHOD_TYPE doesn't map to any real C++ type the result of
16732 the deduction can not be of that type. */
16733 if (TREE_CODE (arg) == METHOD_TYPE)
16734 return unify_method_type_error (explain_p, arg);
16736 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16737 return unify_success (explain_p);
16739 case TEMPLATE_PARM_INDEX:
16740 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
16741 if (tparm == error_mark_node)
16742 return unify_invalid (explain_p);
16744 if (TEMPLATE_PARM_LEVEL (parm)
16745 != template_decl_level (tparm))
16747 /* The PARM is not one we're trying to unify. Just check
16748 to see if it matches ARG. */
16749 int result = !(TREE_CODE (arg) == TREE_CODE (parm)
16750 && cp_tree_equal (parm, arg));
16752 unify_expression_unequal (explain_p, parm, arg);
16756 idx = TEMPLATE_PARM_IDX (parm);
16757 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
16761 int x = !cp_tree_equal (targ, arg);
16763 unify_inconsistency (explain_p, parm, targ, arg);
16767 /* [temp.deduct.type] If, in the declaration of a function template
16768 with a non-type template-parameter, the non-type
16769 template-parameter is used in an expression in the function
16770 parameter-list and, if the corresponding template-argument is
16771 deduced, the template-argument type shall match the type of the
16772 template-parameter exactly, except that a template-argument
16773 deduced from an array bound may be of any integral type.
16774 The non-type parameter might use already deduced type parameters. */
16775 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
16776 if (!TREE_TYPE (arg))
16777 /* Template-parameter dependent expression. Just accept it for now.
16778 It will later be processed in convert_template_argument. */
16780 else if (same_type_p (TREE_TYPE (arg), tparm))
16782 else if ((strict & UNIFY_ALLOW_INTEGER)
16783 && (TREE_CODE (tparm) == INTEGER_TYPE
16784 || TREE_CODE (tparm) == BOOLEAN_TYPE))
16785 /* Convert the ARG to the type of PARM; the deduced non-type
16786 template argument must exactly match the types of the
16787 corresponding parameter. */
16788 arg = fold (build_nop (tparm, arg));
16789 else if (uses_template_parms (tparm))
16790 /* We haven't deduced the type of this parameter yet. Try again
16792 return unify_success (explain_p);
16794 return unify_type_mismatch (explain_p, tparm, arg);
16796 /* If ARG is a parameter pack or an expansion, we cannot unify
16797 against it unless PARM is also a parameter pack. */
16798 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
16799 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
16800 return unify_parameter_pack_mismatch (explain_p, parm, arg);
16802 arg = strip_typedefs_expr (arg);
16803 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
16804 return unify_success (explain_p);
16808 /* A pointer-to-member constant can be unified only with
16809 another constant. */
16810 if (TREE_CODE (arg) != PTRMEM_CST)
16811 return unify_ptrmem_cst_mismatch (explain_p, parm, arg);
16813 /* Just unify the class member. It would be useless (and possibly
16814 wrong, depending on the strict flags) to unify also
16815 PTRMEM_CST_CLASS, because we want to be sure that both parm and
16816 arg refer to the same variable, even if through different
16817 classes. For instance:
16819 struct A { int x; };
16822 Unification of &A::x and &B::x must succeed. */
16823 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
16824 PTRMEM_CST_MEMBER (arg), strict, explain_p);
16829 if (TREE_CODE (arg) != POINTER_TYPE)
16830 return unify_type_mismatch (explain_p, parm, arg);
16832 /* [temp.deduct.call]
16834 A can be another pointer or pointer to member type that can
16835 be converted to the deduced A via a qualification
16836 conversion (_conv.qual_).
16838 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
16839 This will allow for additional cv-qualification of the
16840 pointed-to types if appropriate. */
16842 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
16843 /* The derived-to-base conversion only persists through one
16844 level of pointers. */
16845 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
16847 return unify (tparms, targs, TREE_TYPE (parm),
16848 TREE_TYPE (arg), strict, explain_p);
16851 case REFERENCE_TYPE:
16852 if (TREE_CODE (arg) != REFERENCE_TYPE)
16853 return unify_type_mismatch (explain_p, parm, arg);
16854 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16855 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16858 if (TREE_CODE (arg) != ARRAY_TYPE)
16859 return unify_type_mismatch (explain_p, parm, arg);
16860 if ((TYPE_DOMAIN (parm) == NULL_TREE)
16861 != (TYPE_DOMAIN (arg) == NULL_TREE))
16862 return unify_type_mismatch (explain_p, parm, arg);
16863 RECUR_AND_CHECK_FAILURE (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
16864 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p);
16865 if (TYPE_DOMAIN (parm) != NULL_TREE)
16872 /* Our representation of array types uses "N - 1" as the
16873 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
16874 not an integer constant. We cannot unify arbitrarily
16875 complex expressions, so we eliminate the MINUS_EXPRs
16877 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
16878 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
16881 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
16882 parm_max = TREE_OPERAND (parm_max, 0);
16884 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
16885 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
16888 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
16889 trying to unify the type of a variable with the type
16890 of a template parameter. For example:
16892 template <unsigned int N>
16893 void f (char (&) [N]);
16900 Here, the type of the ARG will be "int [g(i)]", and
16901 may be a SAVE_EXPR, etc. */
16902 if (TREE_CODE (arg_max) != MINUS_EXPR)
16903 return unify_vla_arg (explain_p, arg);
16904 arg_max = TREE_OPERAND (arg_max, 0);
16907 /* If only one of the bounds used a MINUS_EXPR, compensate
16908 by adding one to the other bound. */
16909 if (parm_cst && !arg_cst)
16910 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
16914 else if (arg_cst && !parm_cst)
16915 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
16920 RECUR_AND_CHECK_FAILURE (tparms, targs, parm_max, arg_max,
16921 UNIFY_ALLOW_INTEGER, explain_p);
16923 return unify_success (explain_p);
16930 case ENUMERAL_TYPE:
16933 if (TREE_CODE (arg) != TREE_CODE (parm))
16934 return unify_type_mismatch (explain_p, parm, arg);
16936 /* We have already checked cv-qualification at the top of the
16938 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
16939 return unify_type_mismatch (explain_p, parm, arg);
16941 /* As far as unification is concerned, this wins. Later checks
16942 will invalidate it if necessary. */
16943 return unify_success (explain_p);
16945 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
16946 /* Type INTEGER_CST can come from ordinary constant template args. */
16948 while (TREE_CODE (arg) == NOP_EXPR)
16949 arg = TREE_OPERAND (arg, 0);
16951 if (TREE_CODE (arg) != INTEGER_CST)
16952 return unify_template_argument_mismatch (explain_p, parm, arg);
16953 return (tree_int_cst_equal (parm, arg)
16954 ? unify_success (explain_p)
16955 : unify_template_argument_mismatch (explain_p, parm, arg));
16959 int i, len, argslen;
16960 int parm_variadic_p = 0;
16962 if (TREE_CODE (arg) != TREE_VEC)
16963 return unify_template_argument_mismatch (explain_p, parm, arg);
16965 len = TREE_VEC_LENGTH (parm);
16966 argslen = TREE_VEC_LENGTH (arg);
16968 /* Check for pack expansions in the parameters. */
16969 for (i = 0; i < len; ++i)
16971 if (PACK_EXPANSION_P (TREE_VEC_ELT (parm, i)))
16974 /* We can unify against something with a trailing
16976 parm_variadic_p = 1;
16978 /* [temp.deduct.type]/9: If the template argument list of
16979 P contains a pack expansion that is not the last
16980 template argument, the entire template argument list
16981 is a non-deduced context. */
16982 return unify_success (explain_p);
16986 /* If we don't have enough arguments to satisfy the parameters
16987 (not counting the pack expression at the end), or we have
16988 too many arguments for a parameter list that doesn't end in
16989 a pack expression, we can't unify. */
16990 if (parm_variadic_p
16991 ? argslen < len - parm_variadic_p
16993 return unify_arity (explain_p, TREE_VEC_LENGTH (arg), len);
16995 /* Unify all of the parameters that precede the (optional)
16996 pack expression. */
16997 for (i = 0; i < len - parm_variadic_p; ++i)
16999 RECUR_AND_CHECK_FAILURE (tparms, targs,
17000 TREE_VEC_ELT (parm, i),
17001 TREE_VEC_ELT (arg, i),
17002 UNIFY_ALLOW_NONE, explain_p);
17004 if (parm_variadic_p)
17005 return unify_pack_expansion (tparms, targs, parm, arg,
17007 /*subr=*/true, explain_p);
17008 return unify_success (explain_p);
17013 if (TREE_CODE (arg) != TREE_CODE (parm))
17014 return unify_type_mismatch (explain_p, parm, arg);
17016 if (TYPE_PTRMEMFUNC_P (parm))
17018 if (!TYPE_PTRMEMFUNC_P (arg))
17019 return unify_type_mismatch (explain_p, parm, arg);
17021 return unify (tparms, targs,
17022 TYPE_PTRMEMFUNC_FN_TYPE (parm),
17023 TYPE_PTRMEMFUNC_FN_TYPE (arg),
17024 strict, explain_p);
17027 if (CLASSTYPE_TEMPLATE_INFO (parm))
17029 tree t = NULL_TREE;
17031 if (strict_in & UNIFY_ALLOW_DERIVED)
17033 /* First, we try to unify the PARM and ARG directly. */
17034 t = try_class_unification (tparms, targs,
17035 parm, arg, explain_p);
17039 /* Fallback to the special case allowed in
17040 [temp.deduct.call]:
17042 If P is a class, and P has the form
17043 template-id, then A can be a derived class of
17044 the deduced A. Likewise, if P is a pointer to
17045 a class of the form template-id, A can be a
17046 pointer to a derived class pointed to by the
17048 enum template_base_result r;
17049 r = get_template_base (tparms, targs, parm, arg,
17053 return unify_no_common_base (explain_p, r, parm, arg);
17056 else if (CLASSTYPE_TEMPLATE_INFO (arg)
17057 && (CLASSTYPE_TI_TEMPLATE (parm)
17058 == CLASSTYPE_TI_TEMPLATE (arg)))
17059 /* Perhaps PARM is something like S<U> and ARG is S<int>.
17060 Then, we should unify `int' and `U'. */
17063 /* There's no chance of unification succeeding. */
17064 return unify_type_mismatch (explain_p, parm, arg);
17066 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
17067 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE, explain_p);
17069 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
17070 return unify_type_mismatch (explain_p, parm, arg);
17071 return unify_success (explain_p);
17074 case FUNCTION_TYPE:
17076 unsigned int nargs;
17081 if (TREE_CODE (arg) != TREE_CODE (parm))
17082 return unify_type_mismatch (explain_p, parm, arg);
17084 /* CV qualifications for methods can never be deduced, they must
17085 match exactly. We need to check them explicitly here,
17086 because type_unification_real treats them as any other
17087 cv-qualified parameter. */
17088 if (TREE_CODE (parm) == METHOD_TYPE
17089 && (!check_cv_quals_for_unify
17091 class_of_this_parm (arg),
17092 class_of_this_parm (parm))))
17093 return unify_cv_qual_mismatch (explain_p, parm, arg);
17095 RECUR_AND_CHECK_FAILURE (tparms, targs, TREE_TYPE (parm),
17096 TREE_TYPE (arg), UNIFY_ALLOW_NONE, explain_p);
17098 nargs = list_length (TYPE_ARG_TYPES (arg));
17099 args = XALLOCAVEC (tree, nargs);
17100 for (a = TYPE_ARG_TYPES (arg), i = 0;
17101 a != NULL_TREE && a != void_list_node;
17102 a = TREE_CHAIN (a), ++i)
17103 args[i] = TREE_VALUE (a);
17106 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
17107 args, nargs, 1, DEDUCE_EXACT,
17108 LOOKUP_NORMAL, NULL, explain_p);
17112 /* Unify a pointer to member with a pointer to member function, which
17113 deduces the type of the member as a function type. */
17114 if (TYPE_PTRMEMFUNC_P (arg))
17119 /* Check top-level cv qualifiers */
17120 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
17121 return unify_cv_qual_mismatch (explain_p, parm, arg);
17123 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
17124 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg),
17125 UNIFY_ALLOW_NONE, explain_p);
17127 /* Determine the type of the function we are unifying against. */
17128 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
17130 build_function_type (TREE_TYPE (method_type),
17131 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
17133 /* Extract the cv-qualifiers and ref-qualifier of the member
17134 function from the implicit object parameter and place them
17135 on the function type to be restored later. */
17136 fntype = apply_memfn_quals (fntype,
17137 type_memfn_quals (method_type),
17138 type_memfn_rqual (method_type));
17139 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict, explain_p);
17142 if (TREE_CODE (arg) != OFFSET_TYPE)
17143 return unify_type_mismatch (explain_p, parm, arg);
17144 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
17145 TYPE_OFFSET_BASETYPE (arg),
17146 UNIFY_ALLOW_NONE, explain_p);
17147 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
17148 strict, explain_p);
17151 if (DECL_TEMPLATE_PARM_P (parm))
17152 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict, explain_p);
17153 if (arg != integral_constant_value (parm))
17154 return unify_template_argument_mismatch (explain_p, parm, arg);
17155 return unify_success (explain_p);
17158 case TEMPLATE_DECL:
17159 /* Matched cases are handled by the ARG == PARM test above. */
17160 return unify_template_argument_mismatch (explain_p, parm, arg);
17163 /* A non-type template parameter that is a variable should be a
17164 an integral constant, in which case, it whould have been
17165 folded into its (constant) value. So we should not be getting
17166 a variable here. */
17167 gcc_unreachable ();
17169 case TYPE_ARGUMENT_PACK:
17170 case NONTYPE_ARGUMENT_PACK:
17171 return unify (tparms, targs, ARGUMENT_PACK_ARGS (parm),
17172 ARGUMENT_PACK_ARGS (arg), strict, explain_p);
17175 case DECLTYPE_TYPE:
17176 case UNDERLYING_TYPE:
17177 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE,
17178 or UNDERLYING_TYPE nodes. */
17179 return unify_success (explain_p);
17182 /* Unification fails if we hit an error node. */
17183 return unify_invalid (explain_p);
17186 /* An unresolved overload is a nondeduced context. */
17187 if (is_overloaded_fn (parm) || type_unknown_p (parm))
17188 return unify_success (explain_p);
17189 gcc_assert (EXPR_P (parm));
17191 /* We must be looking at an expression. This can happen with
17195 void foo(S<I>, S<I + 2>);
17197 This is a "nondeduced context":
17201 The nondeduced contexts are:
17203 --A type that is a template-id in which one or more of
17204 the template-arguments is an expression that references
17205 a template-parameter.
17207 In these cases, we assume deduction succeeded, but don't
17208 actually infer any unifications. */
17210 if (!uses_template_parms (parm)
17211 && !template_args_equal (parm, arg))
17212 return unify_expression_unequal (explain_p, parm, arg);
17214 return unify_success (explain_p);
17217 #undef RECUR_AND_CHECK_FAILURE
17219 /* Note that DECL can be defined in this translation unit, if
17223 mark_definable (tree decl)
17226 DECL_NOT_REALLY_EXTERN (decl) = 1;
17227 FOR_EACH_CLONE (clone, decl)
17228 DECL_NOT_REALLY_EXTERN (clone) = 1;
17231 /* Called if RESULT is explicitly instantiated, or is a member of an
17232 explicitly instantiated class. */
17235 mark_decl_instantiated (tree result, int extern_p)
17237 SET_DECL_EXPLICIT_INSTANTIATION (result);
17239 /* If this entity has already been written out, it's too late to
17240 make any modifications. */
17241 if (TREE_ASM_WRITTEN (result))
17244 if (TREE_CODE (result) != FUNCTION_DECL)
17245 /* The TREE_PUBLIC flag for function declarations will have been
17246 set correctly by tsubst. */
17247 TREE_PUBLIC (result) = 1;
17249 /* This might have been set by an earlier implicit instantiation. */
17250 DECL_COMDAT (result) = 0;
17253 DECL_NOT_REALLY_EXTERN (result) = 0;
17256 mark_definable (result);
17257 /* Always make artificials weak. */
17258 if (DECL_ARTIFICIAL (result) && flag_weak)
17259 comdat_linkage (result);
17260 /* For WIN32 we also want to put explicit instantiations in
17261 linkonce sections. */
17262 else if (TREE_PUBLIC (result))
17263 maybe_make_one_only (result);
17266 /* If EXTERN_P, then this function will not be emitted -- unless
17267 followed by an explicit instantiation, at which point its linkage
17268 will be adjusted. If !EXTERN_P, then this function will be
17269 emitted here. In neither circumstance do we want
17270 import_export_decl to adjust the linkage. */
17271 DECL_INTERFACE_KNOWN (result) = 1;
17274 /* Subroutine of more_specialized_fn: check whether TARGS is missing any
17275 important template arguments. If any are missing, we check whether
17276 they're important by using error_mark_node for substituting into any
17277 args that were used for partial ordering (the ones between ARGS and END)
17278 and seeing if it bubbles up. */
17281 check_undeduced_parms (tree targs, tree args, tree end)
17283 bool found = false;
17285 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i)
17286 if (TREE_VEC_ELT (targs, i) == NULL_TREE)
17289 TREE_VEC_ELT (targs, i) = error_mark_node;
17293 tree substed = tsubst_arg_types (args, targs, end, tf_none, NULL_TREE);
17294 if (substed == error_mark_node)
17300 /* Given two function templates PAT1 and PAT2, return:
17302 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
17303 -1 if PAT2 is more specialized than PAT1.
17304 0 if neither is more specialized.
17306 LEN indicates the number of parameters we should consider
17307 (defaulted parameters should not be considered).
17309 The 1998 std underspecified function template partial ordering, and
17310 DR214 addresses the issue. We take pairs of arguments, one from
17311 each of the templates, and deduce them against each other. One of
17312 the templates will be more specialized if all the *other*
17313 template's arguments deduce against its arguments and at least one
17314 of its arguments *does* *not* deduce against the other template's
17315 corresponding argument. Deduction is done as for class templates.
17316 The arguments used in deduction have reference and top level cv
17317 qualifiers removed. Iff both arguments were originally reference
17318 types *and* deduction succeeds in both directions, the template
17319 with the more cv-qualified argument wins for that pairing (if
17320 neither is more cv-qualified, they both are equal). Unlike regular
17321 deduction, after all the arguments have been deduced in this way,
17322 we do *not* verify the deduced template argument values can be
17323 substituted into non-deduced contexts.
17325 The logic can be a bit confusing here, because we look at deduce1 and
17326 targs1 to see if pat2 is at least as specialized, and vice versa; if we
17327 can find template arguments for pat1 to make arg1 look like arg2, that
17328 means that arg2 is at least as specialized as arg1. */
17331 more_specialized_fn (tree pat1, tree pat2, int len)
17333 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
17334 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
17335 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
17336 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
17337 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
17338 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
17339 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
17340 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
17341 tree origs1, origs2;
17342 bool lose1 = false;
17343 bool lose2 = false;
17345 /* Remove the this parameter from non-static member functions. If
17346 one is a non-static member function and the other is not a static
17347 member function, remove the first parameter from that function
17348 also. This situation occurs for operator functions where we
17349 locate both a member function (with this pointer) and non-member
17350 operator (with explicit first operand). */
17351 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
17353 len--; /* LEN is the number of significant arguments for DECL1 */
17354 args1 = TREE_CHAIN (args1);
17355 if (!DECL_STATIC_FUNCTION_P (decl2))
17356 args2 = TREE_CHAIN (args2);
17358 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
17360 args2 = TREE_CHAIN (args2);
17361 if (!DECL_STATIC_FUNCTION_P (decl1))
17364 args1 = TREE_CHAIN (args1);
17368 /* If only one is a conversion operator, they are unordered. */
17369 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
17372 /* Consider the return type for a conversion function */
17373 if (DECL_CONV_FN_P (decl1))
17375 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
17376 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
17380 processing_template_decl++;
17386 /* Stop when an ellipsis is seen. */
17387 && args1 != NULL_TREE && args2 != NULL_TREE)
17389 tree arg1 = TREE_VALUE (args1);
17390 tree arg2 = TREE_VALUE (args2);
17391 int deduce1, deduce2;
17395 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17396 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17398 /* When both arguments are pack expansions, we need only
17399 unify the patterns themselves. */
17400 arg1 = PACK_EXPANSION_PATTERN (arg1);
17401 arg2 = PACK_EXPANSION_PATTERN (arg2);
17403 /* This is the last comparison we need to do. */
17407 if (TREE_CODE (arg1) == REFERENCE_TYPE)
17409 arg1 = TREE_TYPE (arg1);
17410 quals1 = cp_type_quals (arg1);
17413 if (TREE_CODE (arg2) == REFERENCE_TYPE)
17415 arg2 = TREE_TYPE (arg2);
17416 quals2 = cp_type_quals (arg2);
17419 arg1 = TYPE_MAIN_VARIANT (arg1);
17420 arg2 = TYPE_MAIN_VARIANT (arg2);
17422 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
17424 int i, len2 = list_length (args2);
17425 tree parmvec = make_tree_vec (1);
17426 tree argvec = make_tree_vec (len2);
17429 /* Setup the parameter vector, which contains only ARG1. */
17430 TREE_VEC_ELT (parmvec, 0) = arg1;
17432 /* Setup the argument vector, which contains the remaining
17434 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
17435 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17437 deduce1 = (unify_pack_expansion (tparms1, targs1, parmvec,
17438 argvec, DEDUCE_EXACT,
17439 /*subr=*/true, /*explain_p=*/false)
17442 /* We cannot deduce in the other direction, because ARG1 is
17443 a pack expansion but ARG2 is not. */
17446 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17448 int i, len1 = list_length (args1);
17449 tree parmvec = make_tree_vec (1);
17450 tree argvec = make_tree_vec (len1);
17453 /* Setup the parameter vector, which contains only ARG1. */
17454 TREE_VEC_ELT (parmvec, 0) = arg2;
17456 /* Setup the argument vector, which contains the remaining
17458 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
17459 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
17461 deduce2 = (unify_pack_expansion (tparms2, targs2, parmvec,
17462 argvec, DEDUCE_EXACT,
17463 /*subr=*/true, /*explain_p=*/false)
17466 /* We cannot deduce in the other direction, because ARG2 is
17467 a pack expansion but ARG1 is not.*/
17473 /* The normal case, where neither argument is a pack
17475 deduce1 = (unify (tparms1, targs1, arg1, arg2,
17476 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17478 deduce2 = (unify (tparms2, targs2, arg2, arg1,
17479 UNIFY_ALLOW_NONE, /*explain_p=*/false)
17483 /* If we couldn't deduce arguments for tparms1 to make arg1 match
17484 arg2, then arg2 is not as specialized as arg1. */
17490 /* "If, for a given type, deduction succeeds in both directions
17491 (i.e., the types are identical after the transformations above)
17492 and if the type from the argument template is more cv-qualified
17493 than the type from the parameter template (as described above)
17494 that type is considered to be more specialized than the other. If
17495 neither type is more cv-qualified than the other then neither type
17496 is more specialized than the other." */
17498 if (deduce1 && deduce2
17499 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0)
17501 if ((quals1 & quals2) == quals2)
17503 if ((quals1 & quals2) == quals1)
17507 if (lose1 && lose2)
17508 /* We've failed to deduce something in either direction.
17509 These must be unordered. */
17512 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
17513 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
17514 /* We have already processed all of the arguments in our
17515 handing of the pack expansion type. */
17518 args1 = TREE_CHAIN (args1);
17519 args2 = TREE_CHAIN (args2);
17522 /* "In most cases, all template parameters must have values in order for
17523 deduction to succeed, but for partial ordering purposes a template
17524 parameter may remain without a value provided it is not used in the
17525 types being used for partial ordering."
17527 Thus, if we are missing any of the targs1 we need to substitute into
17528 origs1, then pat2 is not as specialized as pat1. This can happen when
17529 there is a nondeduced context. */
17530 if (!lose2 && check_undeduced_parms (targs1, origs1, args1))
17532 if (!lose1 && check_undeduced_parms (targs2, origs2, args2))
17535 processing_template_decl--;
17537 /* All things being equal, if the next argument is a pack expansion
17538 for one function but not for the other, prefer the
17539 non-variadic function. FIXME this is bogus; see c++/41958. */
17541 && args1 && TREE_VALUE (args1)
17542 && args2 && TREE_VALUE (args2))
17544 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION;
17545 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION;
17548 if (lose1 == lose2)
17556 /* Determine which of two partial specializations of MAIN_TMPL is more
17559 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
17560 to the first partial specialization. The TREE_VALUE is the
17561 innermost set of template parameters for the partial
17562 specialization. PAT2 is similar, but for the second template.
17564 Return 1 if the first partial specialization is more specialized;
17565 -1 if the second is more specialized; 0 if neither is more
17568 See [temp.class.order] for information about determining which of
17569 two templates is more specialized. */
17572 more_specialized_class (tree main_tmpl, tree pat1, tree pat2)
17577 bool any_deductions = false;
17579 tmpl1 = TREE_TYPE (pat1);
17580 tmpl2 = TREE_TYPE (pat2);
17582 /* Just like what happens for functions, if we are ordering between
17583 different class template specializations, we may encounter dependent
17584 types in the arguments, and we need our dependency check functions
17585 to behave correctly. */
17586 ++processing_template_decl;
17587 targs = get_class_bindings (main_tmpl, TREE_VALUE (pat1),
17588 CLASSTYPE_TI_ARGS (tmpl1),
17589 CLASSTYPE_TI_ARGS (tmpl2));
17593 any_deductions = true;
17596 targs = get_class_bindings (main_tmpl, TREE_VALUE (pat2),
17597 CLASSTYPE_TI_ARGS (tmpl2),
17598 CLASSTYPE_TI_ARGS (tmpl1));
17602 any_deductions = true;
17604 --processing_template_decl;
17606 /* In the case of a tie where at least one of the class templates
17607 has a parameter pack at the end, the template with the most
17608 non-packed parameters wins. */
17611 && (template_args_variadic_p (TREE_PURPOSE (pat1))
17612 || template_args_variadic_p (TREE_PURPOSE (pat2))))
17614 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
17615 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
17616 int len1 = TREE_VEC_LENGTH (args1);
17617 int len2 = TREE_VEC_LENGTH (args2);
17619 /* We don't count the pack expansion at the end. */
17620 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
17622 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
17627 else if (len1 < len2)
17634 /* Return the template arguments that will produce the function signature
17635 DECL from the function template FN, with the explicit template
17636 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
17637 also match. Return NULL_TREE if no satisfactory arguments could be
17641 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
17643 int ntparms = DECL_NTPARMS (fn);
17644 tree targs = make_tree_vec (ntparms);
17645 tree decl_type = TREE_TYPE (decl);
17646 tree decl_arg_types;
17648 unsigned int nargs, ix;
17651 gcc_assert (decl != DECL_TEMPLATE_RESULT (fn));
17653 /* Never do unification on the 'this' parameter. */
17654 decl_arg_types = skip_artificial_parms_for (decl,
17655 TYPE_ARG_TYPES (decl_type));
17657 nargs = list_length (decl_arg_types);
17658 args = XALLOCAVEC (tree, nargs);
17659 for (arg = decl_arg_types, ix = 0;
17660 arg != NULL_TREE && arg != void_list_node;
17661 arg = TREE_CHAIN (arg), ++ix)
17662 args[ix] = TREE_VALUE (arg);
17664 if (fn_type_unification (fn, explicit_args, targs,
17666 (check_rettype || DECL_CONV_FN_P (fn)
17667 ? TREE_TYPE (decl_type) : NULL_TREE),
17668 DEDUCE_EXACT, LOOKUP_NORMAL, /*explain_p=*/false)
17669 == error_mark_node)
17675 /* Return the innermost template arguments that, when applied to a partial
17676 specialization of MAIN_TMPL whose innermost template parameters are
17677 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
17680 For example, suppose we have:
17682 template <class T, class U> struct S {};
17683 template <class T> struct S<T*, int> {};
17685 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
17686 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
17687 int}. The resulting vector will be {double}, indicating that `T'
17688 is bound to `double'. */
17691 get_class_bindings (tree main_tmpl, tree tparms, tree spec_args, tree args)
17693 int i, ntparms = TREE_VEC_LENGTH (tparms);
17695 tree innermost_deduced_args;
17697 innermost_deduced_args = make_tree_vec (ntparms);
17698 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17700 deduced_args = copy_node (args);
17701 SET_TMPL_ARGS_LEVEL (deduced_args,
17702 TMPL_ARGS_DEPTH (deduced_args),
17703 innermost_deduced_args);
17706 deduced_args = innermost_deduced_args;
17708 if (unify (tparms, deduced_args,
17709 INNERMOST_TEMPLATE_ARGS (spec_args),
17710 INNERMOST_TEMPLATE_ARGS (args),
17711 UNIFY_ALLOW_NONE, /*explain_p=*/false))
17714 for (i = 0; i < ntparms; ++i)
17715 if (! TREE_VEC_ELT (innermost_deduced_args, i))
17718 /* Verify that nondeduced template arguments agree with the type
17719 obtained from argument deduction.
17723 struct A { typedef int X; };
17724 template <class T, class U> struct C {};
17725 template <class T> struct C<T, typename T::X> {};
17727 Then with the instantiation `C<A, int>', we can deduce that
17728 `T' is `A' but unify () does not check whether `typename T::X'
17730 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
17731 spec_args = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (main_tmpl),
17732 spec_args, main_tmpl,
17733 tf_none, false, false);
17734 if (spec_args == error_mark_node
17735 /* We only need to check the innermost arguments; the other
17736 arguments will always agree. */
17737 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
17738 INNERMOST_TEMPLATE_ARGS (args)))
17741 /* Now that we have bindings for all of the template arguments,
17742 ensure that the arguments deduced for the template template
17743 parameters have compatible template parameter lists. See the use
17744 of template_template_parm_bindings_ok_p in fn_type_unification
17745 for more information. */
17746 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
17749 return deduced_args;
17752 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
17753 Return the TREE_LIST node with the most specialized template, if
17754 any. If there is no most specialized template, the error_mark_node
17757 Note that this function does not look at, or modify, the
17758 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
17759 returned is one of the elements of INSTANTIATIONS, callers may
17760 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
17761 and retrieve it from the value returned. */
17764 most_specialized_instantiation (tree templates)
17768 ++processing_template_decl;
17771 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
17775 if (get_bindings (TREE_VALUE (champ),
17776 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17777 NULL_TREE, /*check_ret=*/true))
17780 if (get_bindings (TREE_VALUE (fn),
17781 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17782 NULL_TREE, /*check_ret=*/true))
17789 /* Equally specialized, move to next function. If there
17790 is no next function, nothing's most specialized. */
17791 fn = TREE_CHAIN (fn);
17799 /* Now verify that champ is better than everything earlier in the
17800 instantiation list. */
17801 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
17802 if (get_bindings (TREE_VALUE (champ),
17803 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
17804 NULL_TREE, /*check_ret=*/true)
17805 || !get_bindings (TREE_VALUE (fn),
17806 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
17807 NULL_TREE, /*check_ret=*/true))
17813 processing_template_decl--;
17816 return error_mark_node;
17821 /* If DECL is a specialization of some template, return the most
17822 general such template. Otherwise, returns NULL_TREE.
17824 For example, given:
17826 template <class T> struct S { template <class U> void f(U); };
17828 if TMPL is `template <class U> void S<int>::f(U)' this will return
17829 the full template. This function will not trace past partial
17830 specializations, however. For example, given in addition:
17832 template <class T> struct S<T*> { template <class U> void f(U); };
17834 if TMPL is `template <class U> void S<int*>::f(U)' this will return
17835 `template <class T> template <class U> S<T*>::f(U)'. */
17838 most_general_template (tree decl)
17840 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
17841 an immediate specialization. */
17842 if (TREE_CODE (decl) == FUNCTION_DECL)
17844 if (DECL_TEMPLATE_INFO (decl)) {
17845 decl = DECL_TI_TEMPLATE (decl);
17847 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
17848 template friend. */
17849 if (TREE_CODE (decl) != TEMPLATE_DECL)
17855 /* Look for more and more general templates. */
17856 while (DECL_TEMPLATE_INFO (decl))
17858 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
17859 (See cp-tree.h for details.) */
17860 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
17863 if (CLASS_TYPE_P (TREE_TYPE (decl))
17864 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
17867 /* Stop if we run into an explicitly specialized class template. */
17868 if (!DECL_NAMESPACE_SCOPE_P (decl)
17869 && DECL_CONTEXT (decl)
17870 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
17873 decl = DECL_TI_TEMPLATE (decl);
17879 /* Return the most specialized of the class template partial
17880 specializations of TMPL which can produce TYPE, a specialization of
17881 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
17882 a _TYPE node corresponding to the partial specialization, while the
17883 TREE_PURPOSE is the set of template arguments that must be
17884 substituted into the TREE_TYPE in order to generate TYPE.
17886 If the choice of partial specialization is ambiguous, a diagnostic
17887 is issued, and the error_mark_node is returned. If there are no
17888 partial specializations of TMPL matching TYPE, then NULL_TREE is
17892 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain)
17894 tree list = NULL_TREE;
17900 tree outer_args = NULL_TREE;
17902 tmpl = most_general_template (tmpl);
17903 args = CLASSTYPE_TI_ARGS (type);
17905 /* For determining which partial specialization to use, only the
17906 innermost args are interesting. */
17907 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
17909 outer_args = strip_innermost_template_args (args, 1);
17910 args = INNERMOST_TEMPLATE_ARGS (args);
17913 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
17915 tree partial_spec_args;
17917 tree parms = TREE_VALUE (t);
17919 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
17921 ++processing_template_decl;
17927 /* Discard the outer levels of args, and then substitute in the
17928 template args from the enclosing class. */
17929 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
17930 partial_spec_args = tsubst_template_args
17931 (partial_spec_args, outer_args, tf_none, NULL_TREE);
17933 /* PARMS already refers to just the innermost parms, but the
17934 template parms in partial_spec_args had their levels lowered
17935 by tsubst, so we need to do the same for the parm list. We
17936 can't just tsubst the TREE_VEC itself, as tsubst wants to
17937 treat a TREE_VEC as an argument vector. */
17938 parms = copy_node (parms);
17939 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
17940 TREE_VEC_ELT (parms, i) =
17941 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
17945 partial_spec_args =
17946 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
17947 add_to_template_args (outer_args,
17948 partial_spec_args),
17950 /*require_all_args=*/true,
17951 /*use_default_args=*/true);
17953 --processing_template_decl;
17955 if (partial_spec_args == error_mark_node)
17956 return error_mark_node;
17958 spec_args = get_class_bindings (tmpl, parms,
17964 spec_args = add_to_template_args (outer_args, spec_args);
17965 list = tree_cons (spec_args, TREE_VALUE (t), list);
17966 TREE_TYPE (list) = TREE_TYPE (t);
17973 ambiguous_p = false;
17976 t = TREE_CHAIN (t);
17977 for (; t; t = TREE_CHAIN (t))
17979 fate = more_specialized_class (tmpl, champ, t);
17986 t = TREE_CHAIN (t);
17989 ambiguous_p = true;
17998 for (t = list; t && t != champ; t = TREE_CHAIN (t))
18000 fate = more_specialized_class (tmpl, champ, t);
18003 ambiguous_p = true;
18011 char *spaces = NULL;
18012 if (!(complain & tf_error))
18013 return error_mark_node;
18014 error ("ambiguous class template instantiation for %q#T", type);
18015 str = ngettext ("candidate is:", "candidates are:", list_length (list));
18016 for (t = list; t; t = TREE_CHAIN (t))
18018 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t));
18019 spaces = spaces ? spaces : get_spaces (str);
18022 return error_mark_node;
18028 /* Explicitly instantiate DECL. */
18031 do_decl_instantiation (tree decl, tree storage)
18033 tree result = NULL_TREE;
18036 if (!decl || decl == error_mark_node)
18037 /* An error occurred, for which grokdeclarator has already issued
18038 an appropriate message. */
18040 else if (! DECL_LANG_SPECIFIC (decl))
18042 error ("explicit instantiation of non-template %q#D", decl);
18045 else if (TREE_CODE (decl) == VAR_DECL)
18047 /* There is an asymmetry here in the way VAR_DECLs and
18048 FUNCTION_DECLs are handled by grokdeclarator. In the case of
18049 the latter, the DECL we get back will be marked as a
18050 template instantiation, and the appropriate
18051 DECL_TEMPLATE_INFO will be set up. This does not happen for
18052 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
18053 should handle VAR_DECLs as it currently handles
18055 if (!DECL_CLASS_SCOPE_P (decl))
18057 error ("%qD is not a static data member of a class template", decl);
18060 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
18061 if (!result || TREE_CODE (result) != VAR_DECL)
18063 error ("no matching template for %qD found", decl);
18066 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
18068 error ("type %qT for explicit instantiation %qD does not match "
18069 "declared type %qT", TREE_TYPE (result), decl,
18074 else if (TREE_CODE (decl) != FUNCTION_DECL)
18076 error ("explicit instantiation of %q#D", decl);
18082 /* Check for various error cases. Note that if the explicit
18083 instantiation is valid the RESULT will currently be marked as an
18084 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
18085 until we get here. */
18087 if (DECL_TEMPLATE_SPECIALIZATION (result))
18089 /* DR 259 [temp.spec].
18091 Both an explicit instantiation and a declaration of an explicit
18092 specialization shall not appear in a program unless the explicit
18093 instantiation follows a declaration of the explicit specialization.
18095 For a given set of template parameters, if an explicit
18096 instantiation of a template appears after a declaration of an
18097 explicit specialization for that template, the explicit
18098 instantiation has no effect. */
18101 else if (DECL_EXPLICIT_INSTANTIATION (result))
18105 No program shall explicitly instantiate any template more
18108 We check DECL_NOT_REALLY_EXTERN so as not to complain when
18109 the first instantiation was `extern' and the second is not,
18110 and EXTERN_P for the opposite case. */
18111 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
18112 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
18113 /* If an "extern" explicit instantiation follows an ordinary
18114 explicit instantiation, the template is instantiated. */
18118 else if (!DECL_IMPLICIT_INSTANTIATION (result))
18120 error ("no matching template for %qD found", result);
18123 else if (!DECL_TEMPLATE_INFO (result))
18125 permerror (input_location, "explicit instantiation of non-template %q#D", result);
18129 if (storage == NULL_TREE)
18131 else if (storage == ridpointers[(int) RID_EXTERN])
18133 if (!in_system_header && (cxx_dialect == cxx98))
18134 pedwarn (input_location, OPT_Wpedantic,
18135 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
18140 error ("storage class %qD applied to template instantiation", storage);
18142 check_explicit_instantiation_namespace (result);
18143 mark_decl_instantiated (result, extern_p);
18145 instantiate_decl (result, /*defer_ok=*/1,
18146 /*expl_inst_class_mem_p=*/false);
18150 mark_class_instantiated (tree t, int extern_p)
18152 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
18153 SET_CLASSTYPE_INTERFACE_KNOWN (t);
18154 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
18155 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
18158 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
18159 rest_of_type_compilation (t, 1);
18163 /* Called from do_type_instantiation through binding_table_foreach to
18164 do recursive instantiation for the type bound in ENTRY. */
18166 bt_instantiate_type_proc (binding_entry entry, void *data)
18168 tree storage = *(tree *) data;
18170 if (MAYBE_CLASS_TYPE_P (entry->type)
18171 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
18172 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
18175 /* Called from do_type_instantiation to instantiate a member
18176 (a member function or a static member variable) of an
18177 explicitly instantiated class template. */
18179 instantiate_class_member (tree decl, int extern_p)
18181 mark_decl_instantiated (decl, extern_p);
18183 instantiate_decl (decl, /*defer_ok=*/1,
18184 /*expl_inst_class_mem_p=*/true);
18187 /* Perform an explicit instantiation of template class T. STORAGE, if
18188 non-null, is the RID for extern, inline or static. COMPLAIN is
18189 nonzero if this is called from the parser, zero if called recursively,
18190 since the standard is unclear (as detailed below). */
18193 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
18198 int previous_instantiation_extern_p = 0;
18200 if (TREE_CODE (t) == TYPE_DECL)
18203 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
18206 (TYPE_TEMPLATE_INFO (t)) ? TYPE_TI_TEMPLATE (t) : NULL;
18208 error ("explicit instantiation of non-class template %qD", tmpl);
18210 error ("explicit instantiation of non-template type %qT", t);
18216 if (!COMPLETE_TYPE_P (t))
18218 if (complain & tf_error)
18219 error ("explicit instantiation of %q#T before definition of template",
18224 if (storage != NULL_TREE)
18226 if (!in_system_header)
18228 if (storage == ridpointers[(int) RID_EXTERN])
18230 if (cxx_dialect == cxx98)
18231 pedwarn (input_location, OPT_Wpedantic,
18232 "ISO C++ 1998 forbids the use of %<extern%> on "
18233 "explicit instantiations");
18236 pedwarn (input_location, OPT_Wpedantic,
18237 "ISO C++ forbids the use of %qE"
18238 " on explicit instantiations", storage);
18241 if (storage == ridpointers[(int) RID_INLINE])
18243 else if (storage == ridpointers[(int) RID_EXTERN])
18245 else if (storage == ridpointers[(int) RID_STATIC])
18249 error ("storage class %qD applied to template instantiation",
18255 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
18257 /* DR 259 [temp.spec].
18259 Both an explicit instantiation and a declaration of an explicit
18260 specialization shall not appear in a program unless the explicit
18261 instantiation follows a declaration of the explicit specialization.
18263 For a given set of template parameters, if an explicit
18264 instantiation of a template appears after a declaration of an
18265 explicit specialization for that template, the explicit
18266 instantiation has no effect. */
18269 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
18273 No program shall explicitly instantiate any template more
18276 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
18277 instantiation was `extern'. If EXTERN_P then the second is.
18278 These cases are OK. */
18279 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
18281 if (!previous_instantiation_extern_p && !extern_p
18282 && (complain & tf_error))
18283 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
18285 /* If we've already instantiated the template, just return now. */
18286 if (!CLASSTYPE_INTERFACE_ONLY (t))
18290 check_explicit_instantiation_namespace (TYPE_NAME (t));
18291 mark_class_instantiated (t, extern_p);
18299 /* In contrast to implicit instantiation, where only the
18300 declarations, and not the definitions, of members are
18301 instantiated, we have here:
18305 The explicit instantiation of a class template specialization
18306 implies the instantiation of all of its members not
18307 previously explicitly specialized in the translation unit
18308 containing the explicit instantiation.
18310 Of course, we can't instantiate member template classes, since
18311 we don't have any arguments for them. Note that the standard
18312 is unclear on whether the instantiation of the members are
18313 *explicit* instantiations or not. However, the most natural
18314 interpretation is that it should be an explicit instantiation. */
18317 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp))
18318 if (TREE_CODE (tmp) == FUNCTION_DECL
18319 && DECL_TEMPLATE_INSTANTIATION (tmp))
18320 instantiate_class_member (tmp, extern_p);
18322 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp))
18323 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
18324 instantiate_class_member (tmp, extern_p);
18326 if (CLASSTYPE_NESTED_UTDS (t))
18327 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
18328 bt_instantiate_type_proc, &storage);
18332 /* Given a function DECL, which is a specialization of TMPL, modify
18333 DECL to be a re-instantiation of TMPL with the same template
18334 arguments. TMPL should be the template into which tsubst'ing
18335 should occur for DECL, not the most general template.
18337 One reason for doing this is a scenario like this:
18340 void f(const T&, int i);
18342 void g() { f(3, 7); }
18345 void f(const T& t, const int i) { }
18347 Note that when the template is first instantiated, with
18348 instantiate_template, the resulting DECL will have no name for the
18349 first parameter, and the wrong type for the second. So, when we go
18350 to instantiate the DECL, we regenerate it. */
18353 regenerate_decl_from_template (tree decl, tree tmpl)
18355 /* The arguments used to instantiate DECL, from the most general
18360 args = DECL_TI_ARGS (decl);
18361 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
18363 /* Make sure that we can see identifiers, and compute access
18365 push_access_scope (decl);
18367 if (TREE_CODE (decl) == FUNCTION_DECL)
18375 args_depth = TMPL_ARGS_DEPTH (args);
18376 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
18377 if (args_depth > parms_depth)
18378 args = get_innermost_template_args (args, parms_depth);
18380 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
18381 args, tf_error, NULL_TREE,
18382 /*defer_ok*/false);
18383 if (specs && specs != error_mark_node)
18384 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
18387 /* Merge parameter declarations. */
18388 decl_parm = skip_artificial_parms_for (decl,
18389 DECL_ARGUMENTS (decl));
18391 = skip_artificial_parms_for (code_pattern,
18392 DECL_ARGUMENTS (code_pattern));
18393 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
18398 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18399 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
18400 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
18402 parm_type = type_decays_to (parm_type);
18403 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18404 TREE_TYPE (decl_parm) = parm_type;
18405 attributes = DECL_ATTRIBUTES (pattern_parm);
18406 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18408 DECL_ATTRIBUTES (decl_parm) = attributes;
18409 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18411 decl_parm = DECL_CHAIN (decl_parm);
18412 pattern_parm = DECL_CHAIN (pattern_parm);
18414 /* Merge any parameters that match with the function parameter
18416 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
18419 tree expanded_types;
18420 /* Expand the TYPE_PACK_EXPANSION that provides the types for
18421 the parameters in this function parameter pack. */
18422 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
18423 args, tf_error, NULL_TREE);
18424 len = TREE_VEC_LENGTH (expanded_types);
18425 for (i = 0; i < len; i++)
18430 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
18431 /* Rename the parameter to include the index. */
18432 DECL_NAME (decl_parm) =
18433 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
18434 parm_type = TREE_VEC_ELT (expanded_types, i);
18435 parm_type = type_decays_to (parm_type);
18436 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
18437 TREE_TYPE (decl_parm) = parm_type;
18438 attributes = DECL_ATTRIBUTES (pattern_parm);
18439 if (DECL_ATTRIBUTES (decl_parm) != attributes)
18441 DECL_ATTRIBUTES (decl_parm) = attributes;
18442 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
18444 decl_parm = DECL_CHAIN (decl_parm);
18447 /* Merge additional specifiers from the CODE_PATTERN. */
18448 if (DECL_DECLARED_INLINE_P (code_pattern)
18449 && !DECL_DECLARED_INLINE_P (decl))
18450 DECL_DECLARED_INLINE_P (decl) = 1;
18452 else if (TREE_CODE (decl) == VAR_DECL)
18454 DECL_INITIAL (decl) =
18455 tsubst_expr (DECL_INITIAL (code_pattern), args,
18456 tf_error, DECL_TI_TEMPLATE (decl),
18457 /*integral_constant_expression_p=*/false);
18458 if (VAR_HAD_UNKNOWN_BOUND (decl))
18459 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args,
18460 tf_error, DECL_TI_TEMPLATE (decl));
18463 gcc_unreachable ();
18465 pop_access_scope (decl);
18468 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
18469 substituted to get DECL. */
18472 template_for_substitution (tree decl)
18474 tree tmpl = DECL_TI_TEMPLATE (decl);
18476 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
18477 for the instantiation. This is not always the most general
18478 template. Consider, for example:
18481 struct S { template <class U> void f();
18482 template <> void f<int>(); };
18484 and an instantiation of S<double>::f<int>. We want TD to be the
18485 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
18486 while (/* An instantiation cannot have a definition, so we need a
18487 more general template. */
18488 DECL_TEMPLATE_INSTANTIATION (tmpl)
18489 /* We must also deal with friend templates. Given:
18491 template <class T> struct S {
18492 template <class U> friend void f() {};
18495 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
18496 so far as the language is concerned, but that's still
18497 where we get the pattern for the instantiation from. On
18498 other hand, if the definition comes outside the class, say:
18500 template <class T> struct S {
18501 template <class U> friend void f();
18503 template <class U> friend void f() {}
18505 we don't need to look any further. That's what the check for
18506 DECL_INITIAL is for. */
18507 || (TREE_CODE (decl) == FUNCTION_DECL
18508 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
18509 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
18511 /* The present template, TD, should not be a definition. If it
18512 were a definition, we should be using it! Note that we
18513 cannot restructure the loop to just keep going until we find
18514 a template with a definition, since that might go too far if
18515 a specialization was declared, but not defined. */
18516 gcc_assert (TREE_CODE (decl) != VAR_DECL
18517 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
18519 /* Fetch the more general template. */
18520 tmpl = DECL_TI_TEMPLATE (tmpl);
18526 /* Returns true if we need to instantiate this template instance even if we
18527 know we aren't going to emit it.. */
18530 always_instantiate_p (tree decl)
18532 /* We always instantiate inline functions so that we can inline them. An
18533 explicit instantiation declaration prohibits implicit instantiation of
18534 non-inline functions. With high levels of optimization, we would
18535 normally inline non-inline functions -- but we're not allowed to do
18536 that for "extern template" functions. Therefore, we check
18537 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
18538 return ((TREE_CODE (decl) == FUNCTION_DECL
18539 && (DECL_DECLARED_INLINE_P (decl)
18540 || type_uses_auto (TREE_TYPE (TREE_TYPE (decl)))))
18541 /* And we need to instantiate static data members so that
18542 their initializers are available in integral constant
18544 || (TREE_CODE (decl) == VAR_DECL
18545 && decl_maybe_constant_var_p (decl)));
18548 /* If FN has a noexcept-specifier that hasn't been instantiated yet,
18549 instantiate it now, modifying TREE_TYPE (fn). */
18552 maybe_instantiate_noexcept (tree fn)
18554 tree fntype, spec, noex, clone;
18556 if (DECL_CLONED_FUNCTION_P (fn))
18557 fn = DECL_CLONED_FUNCTION (fn);
18558 fntype = TREE_TYPE (fn);
18559 spec = TYPE_RAISES_EXCEPTIONS (fntype);
18561 if (!DEFERRED_NOEXCEPT_SPEC_P (spec))
18564 noex = TREE_PURPOSE (spec);
18566 if (TREE_CODE (noex) == DEFERRED_NOEXCEPT)
18568 if (push_tinst_level (fn))
18570 push_access_scope (fn);
18571 push_deferring_access_checks (dk_no_deferred);
18572 input_location = DECL_SOURCE_LOCATION (fn);
18573 noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex),
18574 DEFERRED_NOEXCEPT_ARGS (noex),
18575 tf_warning_or_error, fn,
18576 /*function_p=*/false,
18577 /*integral_constant_expression_p=*/true);
18578 pop_deferring_access_checks ();
18579 pop_access_scope (fn);
18580 pop_tinst_level ();
18581 spec = build_noexcept_spec (noex, tf_warning_or_error);
18582 if (spec == error_mark_node)
18583 spec = noexcept_false_spec;
18586 spec = noexcept_false_spec;
18590 /* This is an implicitly declared function, so NOEX is a list of
18591 other functions to evaluate and merge. */
18593 spec = noexcept_true_spec;
18594 for (elt = noex; elt; elt = OVL_NEXT (elt))
18596 tree fn = OVL_CURRENT (elt);
18598 maybe_instantiate_noexcept (fn);
18599 subspec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn));
18600 spec = merge_exception_specifiers (spec, subspec, NULL_TREE);
18604 TREE_TYPE (fn) = build_exception_variant (fntype, spec);
18606 FOR_EACH_CLONE (clone, fn)
18608 if (TREE_TYPE (clone) == fntype)
18609 TREE_TYPE (clone) = TREE_TYPE (fn);
18611 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone), spec);
18615 /* Produce the definition of D, a _DECL generated from a template. If
18616 DEFER_OK is nonzero, then we don't have to actually do the
18617 instantiation now; we just have to do it sometime. Normally it is
18618 an error if this is an explicit instantiation but D is undefined.
18619 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
18620 explicitly instantiated class template. */
18623 instantiate_decl (tree d, int defer_ok,
18624 bool expl_inst_class_mem_p)
18626 tree tmpl = DECL_TI_TEMPLATE (d);
18633 bool pattern_defined;
18634 location_t saved_loc = input_location;
18639 /* This function should only be used to instantiate templates for
18640 functions and static member variables. */
18641 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
18642 || TREE_CODE (d) == VAR_DECL);
18644 /* Variables are never deferred; if instantiation is required, they
18645 are instantiated right away. That allows for better code in the
18646 case that an expression refers to the value of the variable --
18647 if the variable has a constant value the referring expression can
18648 take advantage of that fact. */
18649 if (TREE_CODE (d) == VAR_DECL
18650 || DECL_DECLARED_CONSTEXPR_P (d))
18653 /* Don't instantiate cloned functions. Instead, instantiate the
18654 functions they cloned. */
18655 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
18656 d = DECL_CLONED_FUNCTION (d);
18658 if (DECL_TEMPLATE_INSTANTIATED (d)
18659 || (TREE_CODE (d) == FUNCTION_DECL
18660 && DECL_DEFAULTED_FN (d) && DECL_INITIAL (d))
18661 || DECL_TEMPLATE_SPECIALIZATION (d))
18662 /* D has already been instantiated or explicitly specialized, so
18663 there's nothing for us to do here.
18665 It might seem reasonable to check whether or not D is an explicit
18666 instantiation, and, if so, stop here. But when an explicit
18667 instantiation is deferred until the end of the compilation,
18668 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
18669 the instantiation. */
18672 /* Check to see whether we know that this template will be
18673 instantiated in some other file, as with "extern template"
18675 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
18677 /* In general, we do not instantiate such templates. */
18678 if (external_p && !always_instantiate_p (d))
18681 gen_tmpl = most_general_template (tmpl);
18682 gen_args = DECL_TI_ARGS (d);
18684 if (tmpl != gen_tmpl)
18685 /* We should already have the extra args. */
18686 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
18687 == TMPL_ARGS_DEPTH (gen_args));
18688 /* And what's in the hash table should match D. */
18689 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
18690 || spec == NULL_TREE);
18692 /* This needs to happen before any tsubsting. */
18693 if (! push_tinst_level (d))
18696 timevar_push (TV_TEMPLATE_INST);
18698 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
18699 for the instantiation. */
18700 td = template_for_substitution (d);
18701 code_pattern = DECL_TEMPLATE_RESULT (td);
18703 /* We should never be trying to instantiate a member of a class
18704 template or partial specialization. */
18705 gcc_assert (d != code_pattern);
18707 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
18708 || DECL_TEMPLATE_SPECIALIZATION (td))
18709 /* In the case of a friend template whose definition is provided
18710 outside the class, we may have too many arguments. Drop the
18711 ones we don't need. The same is true for specializations. */
18712 args = get_innermost_template_args
18713 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
18717 if (TREE_CODE (d) == FUNCTION_DECL)
18718 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE
18719 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern));
18721 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
18723 /* We may be in the middle of deferred access check. Disable it now. */
18724 push_deferring_access_checks (dk_no_deferred);
18726 /* Unless an explicit instantiation directive has already determined
18727 the linkage of D, remember that a definition is available for
18729 if (pattern_defined
18730 && !DECL_INTERFACE_KNOWN (d)
18731 && !DECL_NOT_REALLY_EXTERN (d))
18732 mark_definable (d);
18734 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern);
18735 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern);
18736 input_location = DECL_SOURCE_LOCATION (d);
18738 /* If D is a member of an explicitly instantiated class template,
18739 and no definition is available, treat it like an implicit
18741 if (!pattern_defined && expl_inst_class_mem_p
18742 && DECL_EXPLICIT_INSTANTIATION (d))
18744 /* Leave linkage flags alone on instantiations with anonymous
18746 if (TREE_PUBLIC (d))
18748 DECL_NOT_REALLY_EXTERN (d) = 0;
18749 DECL_INTERFACE_KNOWN (d) = 0;
18751 SET_DECL_IMPLICIT_INSTANTIATION (d);
18754 if (TREE_CODE (d) == FUNCTION_DECL)
18755 maybe_instantiate_noexcept (d);
18757 /* Defer all other templates, unless we have been explicitly
18758 forbidden from doing so. */
18759 if (/* If there is no definition, we cannot instantiate the
18762 /* If it's OK to postpone instantiation, do so. */
18764 /* If this is a static data member that will be defined
18765 elsewhere, we don't want to instantiate the entire data
18766 member, but we do want to instantiate the initializer so that
18767 we can substitute that elsewhere. */
18768 || (external_p && TREE_CODE (d) == VAR_DECL))
18770 /* The definition of the static data member is now required so
18771 we must substitute the initializer. */
18772 if (TREE_CODE (d) == VAR_DECL
18773 && !DECL_INITIAL (d)
18774 && DECL_INITIAL (code_pattern))
18778 bool const_init = false;
18780 ns = decl_namespace_context (d);
18781 push_nested_namespace (ns);
18782 push_nested_class (DECL_CONTEXT (d));
18783 init = tsubst_expr (DECL_INITIAL (code_pattern),
18785 tf_warning_or_error, NULL_TREE,
18786 /*integral_constant_expression_p=*/false);
18787 /* Make sure the initializer is still constant, in case of
18788 circular dependency (template/instantiate6.C). */
18790 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18791 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init,
18792 /*asmspec_tree=*/NULL_TREE,
18793 LOOKUP_ONLYCONVERTING);
18794 pop_nested_class ();
18795 pop_nested_namespace (ns);
18798 /* We restore the source position here because it's used by
18799 add_pending_template. */
18800 input_location = saved_loc;
18802 if (at_eof && !pattern_defined
18803 && DECL_EXPLICIT_INSTANTIATION (d)
18804 && DECL_NOT_REALLY_EXTERN (d))
18807 The definition of a non-exported function template, a
18808 non-exported member function template, or a non-exported
18809 member function or static data member of a class template
18810 shall be present in every translation unit in which it is
18811 explicitly instantiated. */
18812 permerror (input_location, "explicit instantiation of %qD "
18813 "but no definition available", d);
18815 /* If we're in unevaluated context, we just wanted to get the
18816 constant value; this isn't an odr use, so don't queue
18817 a full instantiation. */
18818 if (cp_unevaluated_operand != 0)
18820 /* ??? Historically, we have instantiated inline functions, even
18821 when marked as "extern template". */
18822 if (!(external_p && TREE_CODE (d) == VAR_DECL))
18823 add_pending_template (d);
18826 /* Tell the repository that D is available in this translation unit
18827 -- and see if it is supposed to be instantiated here. */
18828 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
18830 /* In a PCH file, despite the fact that the repository hasn't
18831 requested instantiation in the PCH it is still possible that
18832 an instantiation will be required in a file that includes the
18835 add_pending_template (d);
18836 /* Instantiate inline functions so that the inliner can do its
18837 job, even though we'll not be emitting a copy of this
18839 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
18843 fn_context = decl_function_context (d);
18844 nested = (current_function_decl != NULL_TREE);
18846 push_to_top_level ();
18848 push_function_context ();
18850 /* Mark D as instantiated so that recursive calls to
18851 instantiate_decl do not try to instantiate it again. */
18852 DECL_TEMPLATE_INSTANTIATED (d) = 1;
18854 /* Regenerate the declaration in case the template has been modified
18855 by a subsequent redeclaration. */
18856 regenerate_decl_from_template (d, td);
18858 /* We already set the file and line above. Reset them now in case
18859 they changed as a result of calling regenerate_decl_from_template. */
18860 input_location = DECL_SOURCE_LOCATION (d);
18862 if (TREE_CODE (d) == VAR_DECL)
18865 bool const_init = false;
18867 /* Clear out DECL_RTL; whatever was there before may not be right
18868 since we've reset the type of the declaration. */
18869 SET_DECL_RTL (d, NULL);
18870 DECL_IN_AGGR_P (d) = 0;
18872 /* The initializer is placed in DECL_INITIAL by
18873 regenerate_decl_from_template so we don't need to
18874 push/pop_access_scope again here. Pull it out so that
18875 cp_finish_decl can process it. */
18876 init = DECL_INITIAL (d);
18877 DECL_INITIAL (d) = NULL_TREE;
18878 DECL_INITIALIZED_P (d) = 0;
18880 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
18881 initializer. That function will defer actual emission until
18882 we have a chance to determine linkage. */
18883 DECL_EXTERNAL (d) = 0;
18885 /* Enter the scope of D so that access-checking works correctly. */
18886 push_nested_class (DECL_CONTEXT (d));
18887 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern);
18888 cp_finish_decl (d, init, const_init, NULL_TREE, 0);
18889 pop_nested_class ();
18891 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern))
18892 synthesize_method (d);
18893 else if (TREE_CODE (d) == FUNCTION_DECL)
18895 struct pointer_map_t *saved_local_specializations;
18900 /* Save away the current list, in case we are instantiating one
18901 template from within the body of another. */
18902 saved_local_specializations = local_specializations;
18904 /* Set up the list of local specializations. */
18905 local_specializations = pointer_map_create ();
18907 /* Set up context. */
18908 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
18910 /* Some typedefs referenced from within the template code need to be
18911 access checked at template instantiation time, i.e now. These
18912 types were added to the template at parsing time. Let's get those
18913 and perform the access checks then. */
18914 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (gen_tmpl),
18917 /* Create substitution entries for the parameters. */
18918 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
18919 tmpl_parm = DECL_ARGUMENTS (subst_decl);
18920 spec_parm = DECL_ARGUMENTS (d);
18921 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
18923 register_local_specialization (spec_parm, tmpl_parm);
18924 spec_parm = skip_artificial_parms_for (d, spec_parm);
18925 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
18927 for (; tmpl_parm; tmpl_parm = DECL_CHAIN (tmpl_parm))
18929 if (!FUNCTION_PARAMETER_PACK_P (tmpl_parm))
18931 register_local_specialization (spec_parm, tmpl_parm);
18932 spec_parm = DECL_CHAIN (spec_parm);
18936 /* Register the (value) argument pack as a specialization of
18937 TMPL_PARM, then move on. */
18938 tree argpack = extract_fnparm_pack (tmpl_parm, &spec_parm);
18939 register_local_specialization (argpack, tmpl_parm);
18942 gcc_assert (!spec_parm);
18944 /* Substitute into the body of the function. */
18945 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
18946 tf_warning_or_error, tmpl,
18947 /*integral_constant_expression_p=*/false);
18949 /* Set the current input_location to the end of the function
18950 so that finish_function knows where we are. */
18951 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
18953 /* We don't need the local specializations any more. */
18954 pointer_map_destroy (local_specializations);
18955 local_specializations = saved_local_specializations;
18957 /* Finish the function. */
18958 d = finish_function (0);
18959 expand_or_defer_fn (d);
18962 /* We're not deferring instantiation any more. */
18963 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
18966 pop_from_top_level ();
18968 pop_function_context ();
18971 input_location = saved_loc;
18972 pop_deferring_access_checks ();
18973 pop_tinst_level ();
18975 timevar_pop (TV_TEMPLATE_INST);
18980 /* Run through the list of templates that we wish we could
18981 instantiate, and instantiate any we can. RETRIES is the
18982 number of times we retry pending template instantiation. */
18985 instantiate_pending_templates (int retries)
18988 location_t saved_loc = input_location;
18990 /* Instantiating templates may trigger vtable generation. This in turn
18991 may require further template instantiations. We place a limit here
18992 to avoid infinite loop. */
18993 if (pending_templates && retries >= max_tinst_depth)
18995 tree decl = pending_templates->tinst->decl;
18997 error ("template instantiation depth exceeds maximum of %d"
18998 " instantiating %q+D, possibly from virtual table generation"
18999 " (use -ftemplate-depth= to increase the maximum)",
19000 max_tinst_depth, decl);
19001 if (TREE_CODE (decl) == FUNCTION_DECL)
19002 /* Pretend that we defined it. */
19003 DECL_INITIAL (decl) = error_mark_node;
19009 struct pending_template **t = &pending_templates;
19010 struct pending_template *last = NULL;
19014 tree instantiation = reopen_tinst_level ((*t)->tinst);
19015 bool complete = false;
19017 if (TYPE_P (instantiation))
19021 if (!COMPLETE_TYPE_P (instantiation))
19023 instantiate_class_template (instantiation);
19024 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
19025 for (fn = TYPE_METHODS (instantiation);
19027 fn = TREE_CHAIN (fn))
19028 if (! DECL_ARTIFICIAL (fn))
19029 instantiate_decl (fn,
19031 /*expl_inst_class_mem_p=*/false);
19032 if (COMPLETE_TYPE_P (instantiation))
19036 complete = COMPLETE_TYPE_P (instantiation);
19040 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
19041 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
19044 = instantiate_decl (instantiation,
19046 /*expl_inst_class_mem_p=*/false);
19047 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
19051 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
19052 || DECL_TEMPLATE_INSTANTIATED (instantiation));
19056 /* If INSTANTIATION has been instantiated, then we don't
19057 need to consider it again in the future. */
19065 current_tinst_level = NULL;
19067 last_pending_template = last;
19069 while (reconsider);
19071 input_location = saved_loc;
19074 /* Substitute ARGVEC into T, which is a list of initializers for
19075 either base class or a non-static data member. The TREE_PURPOSEs
19076 are DECLs, and the TREE_VALUEs are the initializer values. Used by
19077 instantiate_decl. */
19080 tsubst_initializer_list (tree t, tree argvec)
19082 tree inits = NULL_TREE;
19084 for (; t; t = TREE_CHAIN (t))
19088 tree expanded_bases = NULL_TREE;
19089 tree expanded_arguments = NULL_TREE;
19092 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
19097 /* Expand the base class expansion type into separate base
19099 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
19100 tf_warning_or_error,
19102 if (expanded_bases == error_mark_node)
19105 /* We'll be building separate TREE_LISTs of arguments for
19107 len = TREE_VEC_LENGTH (expanded_bases);
19108 expanded_arguments = make_tree_vec (len);
19109 for (i = 0; i < len; i++)
19110 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
19112 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
19113 expand each argument in the TREE_VALUE of t. */
19114 expr = make_node (EXPR_PACK_EXPANSION);
19115 PACK_EXPANSION_LOCAL_P (expr) = true;
19116 PACK_EXPANSION_PARAMETER_PACKS (expr) =
19117 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
19119 if (TREE_VALUE (t) == void_type_node)
19120 /* VOID_TYPE_NODE is used to indicate
19121 value-initialization. */
19123 for (i = 0; i < len; i++)
19124 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
19128 /* Substitute parameter packs into each argument in the
19130 in_base_initializer = 1;
19131 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
19133 tree expanded_exprs;
19135 /* Expand the argument. */
19136 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
19138 = tsubst_pack_expansion (expr, argvec,
19139 tf_warning_or_error,
19141 if (expanded_exprs == error_mark_node)
19144 /* Prepend each of the expanded expressions to the
19145 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
19146 for (i = 0; i < len; i++)
19148 TREE_VEC_ELT (expanded_arguments, i) =
19149 tree_cons (NULL_TREE,
19150 TREE_VEC_ELT (expanded_exprs, i),
19151 TREE_VEC_ELT (expanded_arguments, i));
19154 in_base_initializer = 0;
19156 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
19157 since we built them backwards. */
19158 for (i = 0; i < len; i++)
19160 TREE_VEC_ELT (expanded_arguments, i) =
19161 nreverse (TREE_VEC_ELT (expanded_arguments, i));
19166 for (i = 0; i < len; ++i)
19168 if (expanded_bases)
19170 decl = TREE_VEC_ELT (expanded_bases, i);
19171 decl = expand_member_init (decl);
19172 init = TREE_VEC_ELT (expanded_arguments, i);
19177 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
19178 tf_warning_or_error, NULL_TREE);
19180 decl = expand_member_init (decl);
19181 if (decl && !DECL_P (decl))
19182 in_base_initializer = 1;
19184 init = TREE_VALUE (t);
19186 if (init != void_type_node)
19187 init = tsubst_expr (init, argvec,
19188 tf_warning_or_error, NULL_TREE,
19189 /*integral_constant_expression_p=*/false);
19190 if (init == NULL_TREE && tmp != NULL_TREE)
19191 /* If we had an initializer but it instantiated to nothing,
19192 value-initialize the object. This will only occur when
19193 the initializer was a pack expansion where the parameter
19194 packs used in that expansion were of length zero. */
19195 init = void_type_node;
19196 in_base_initializer = 0;
19201 init = build_tree_list (decl, init);
19202 TREE_CHAIN (init) = inits;
19210 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
19213 set_current_access_from_decl (tree decl)
19215 if (TREE_PRIVATE (decl))
19216 current_access_specifier = access_private_node;
19217 else if (TREE_PROTECTED (decl))
19218 current_access_specifier = access_protected_node;
19220 current_access_specifier = access_public_node;
19223 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
19224 is the instantiation (which should have been created with
19225 start_enum) and ARGS are the template arguments to use. */
19228 tsubst_enum (tree tag, tree newtag, tree args)
19232 if (SCOPED_ENUM_P (newtag))
19233 begin_scope (sk_scoped_enum, newtag);
19235 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
19240 decl = TREE_VALUE (e);
19241 /* Note that in a template enum, the TREE_VALUE is the
19242 CONST_DECL, not the corresponding INTEGER_CST. */
19243 value = tsubst_expr (DECL_INITIAL (decl),
19244 args, tf_warning_or_error, NULL_TREE,
19245 /*integral_constant_expression_p=*/true);
19247 /* Give this enumeration constant the correct access. */
19248 set_current_access_from_decl (decl);
19250 /* Actually build the enumerator itself. */
19252 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl));
19255 if (SCOPED_ENUM_P (newtag))
19258 finish_enum_value_list (newtag);
19259 finish_enum (newtag);
19261 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
19262 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
19265 /* DECL is a FUNCTION_DECL that is a template specialization. Return
19266 its type -- but without substituting the innermost set of template
19267 arguments. So, innermost set of template parameters will appear in
19271 get_mostly_instantiated_function_type (tree decl)
19279 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
19280 targs = DECL_TI_ARGS (decl);
19281 tparms = DECL_TEMPLATE_PARMS (tmpl);
19282 parm_depth = TMPL_PARMS_DEPTH (tparms);
19284 /* There should be as many levels of arguments as there are levels
19286 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
19288 fn_type = TREE_TYPE (tmpl);
19290 if (parm_depth == 1)
19291 /* No substitution is necessary. */
19298 /* Replace the innermost level of the TARGS with NULL_TREEs to
19299 let tsubst know not to substitute for those parameters. */
19300 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
19301 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
19302 SET_TMPL_ARGS_LEVEL (partial_args, i,
19303 TMPL_ARGS_LEVEL (targs, i));
19304 SET_TMPL_ARGS_LEVEL (partial_args,
19305 TMPL_ARGS_DEPTH (targs),
19306 make_tree_vec (DECL_NTPARMS (tmpl)));
19308 /* Make sure that we can see identifiers, and compute access
19310 push_access_scope (decl);
19312 ++processing_template_decl;
19313 /* Now, do the (partial) substitution to figure out the
19314 appropriate function type. */
19315 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
19316 --processing_template_decl;
19318 /* Substitute into the template parameters to obtain the real
19319 innermost set of parameters. This step is important if the
19320 innermost set of template parameters contains value
19321 parameters whose types depend on outer template parameters. */
19322 TREE_VEC_LENGTH (partial_args)--;
19323 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
19325 pop_access_scope (decl);
19331 /* Return truthvalue if we're processing a template different from
19332 the last one involved in diagnostics. */
19334 problematic_instantiation_changed (void)
19336 return current_tinst_level != last_error_tinst_level;
19339 /* Remember current template involved in diagnostics. */
19341 record_last_problematic_instantiation (void)
19343 last_error_tinst_level = current_tinst_level;
19346 struct tinst_level *
19347 current_instantiation (void)
19349 return current_tinst_level;
19352 /* [temp.param] Check that template non-type parm TYPE is of an allowable
19353 type. Return zero for ok, nonzero for disallowed. Issue error and
19354 warning messages under control of COMPLAIN. */
19357 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
19359 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
19361 else if (POINTER_TYPE_P (type))
19363 else if (TYPE_PTRMEM_P (type))
19365 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
19367 else if (TREE_CODE (type) == TYPENAME_TYPE)
19369 else if (TREE_CODE (type) == DECLTYPE_TYPE)
19371 else if (TREE_CODE (type) == NULLPTR_TYPE)
19374 if (complain & tf_error)
19376 if (type == error_mark_node)
19377 inform (input_location, "invalid template non-type parameter");
19379 error ("%q#T is not a valid type for a template non-type parameter",
19385 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
19386 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
19389 dependent_type_p_r (tree type)
19395 A type is dependent if it is:
19397 -- a template parameter. Template template parameters are types
19398 for us (since TYPE_P holds true for them) so we handle
19400 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
19401 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
19403 /* -- a qualified-id with a nested-name-specifier which contains a
19404 class-name that names a dependent type or whose unqualified-id
19405 names a dependent type. */
19406 if (TREE_CODE (type) == TYPENAME_TYPE)
19408 /* -- a cv-qualified type where the cv-unqualified type is
19410 type = TYPE_MAIN_VARIANT (type);
19411 /* -- a compound type constructed from any dependent type. */
19412 if (TYPE_PTRMEM_P (type))
19413 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
19414 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
19416 else if (TREE_CODE (type) == POINTER_TYPE
19417 || TREE_CODE (type) == REFERENCE_TYPE)
19418 return dependent_type_p (TREE_TYPE (type));
19419 else if (TREE_CODE (type) == FUNCTION_TYPE
19420 || TREE_CODE (type) == METHOD_TYPE)
19424 if (dependent_type_p (TREE_TYPE (type)))
19426 for (arg_type = TYPE_ARG_TYPES (type);
19428 arg_type = TREE_CHAIN (arg_type))
19429 if (dependent_type_p (TREE_VALUE (arg_type)))
19433 /* -- an array type constructed from any dependent type or whose
19434 size is specified by a constant expression that is
19437 We checked for type- and value-dependence of the bounds in
19438 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */
19439 if (TREE_CODE (type) == ARRAY_TYPE)
19441 if (TYPE_DOMAIN (type)
19442 && dependent_type_p (TYPE_DOMAIN (type)))
19444 return dependent_type_p (TREE_TYPE (type));
19447 /* -- a template-id in which either the template name is a template
19449 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
19451 /* ... or any of the template arguments is a dependent type or
19452 an expression that is type-dependent or value-dependent. */
19453 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
19454 && (any_dependent_template_arguments_p
19455 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
19458 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are
19459 dependent; if the argument of the `typeof' expression is not
19460 type-dependent, then it should already been have resolved. */
19461 if (TREE_CODE (type) == TYPEOF_TYPE
19462 || TREE_CODE (type) == DECLTYPE_TYPE
19463 || TREE_CODE (type) == UNDERLYING_TYPE)
19466 /* A template argument pack is dependent if any of its packed
19468 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
19470 tree args = ARGUMENT_PACK_ARGS (type);
19471 int i, len = TREE_VEC_LENGTH (args);
19472 for (i = 0; i < len; ++i)
19473 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
19477 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
19478 be template parameters. */
19479 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
19482 /* The standard does not specifically mention types that are local
19483 to template functions or local classes, but they should be
19484 considered dependent too. For example:
19486 template <int I> void f() {
19491 The size of `E' cannot be known until the value of `I' has been
19492 determined. Therefore, `E' must be considered dependent. */
19493 scope = TYPE_CONTEXT (type);
19494 if (scope && TYPE_P (scope))
19495 return dependent_type_p (scope);
19496 /* Don't use type_dependent_expression_p here, as it can lead
19497 to infinite recursion trying to determine whether a lambda
19498 nested in a lambda is dependent (c++/47687). */
19499 else if (scope && TREE_CODE (scope) == FUNCTION_DECL
19500 && DECL_LANG_SPECIFIC (scope)
19501 && DECL_TEMPLATE_INFO (scope)
19502 && (any_dependent_template_arguments_p
19503 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope)))))
19506 /* Other types are non-dependent. */
19510 /* Returns TRUE if TYPE is dependent, in the sense of
19511 [temp.dep.type]. Note that a NULL type is considered dependent. */
19514 dependent_type_p (tree type)
19516 /* If there are no template parameters in scope, then there can't be
19517 any dependent types. */
19518 if (!processing_template_decl)
19520 /* If we are not processing a template, then nobody should be
19521 providing us with a dependent type. */
19523 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
19527 /* If the type is NULL, we have not computed a type for the entity
19528 in question; in that case, the type is dependent. */
19532 /* Erroneous types can be considered non-dependent. */
19533 if (type == error_mark_node)
19536 /* If we have not already computed the appropriate value for TYPE,
19538 if (!TYPE_DEPENDENT_P_VALID (type))
19540 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
19541 TYPE_DEPENDENT_P_VALID (type) = 1;
19544 return TYPE_DEPENDENT_P (type);
19547 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
19548 lookup. In other words, a dependent type that is not the current
19552 dependent_scope_p (tree scope)
19554 return (scope && TYPE_P (scope) && dependent_type_p (scope)
19555 && !currently_open_class (scope));
19558 /* T is a SCOPE_REF; return whether we need to consider it
19559 instantiation-dependent so that we can check access at instantiation
19560 time even though we know which member it resolves to. */
19563 instantiation_dependent_scope_ref_p (tree t)
19565 if (DECL_P (TREE_OPERAND (t, 1))
19566 && CLASS_TYPE_P (TREE_OPERAND (t, 0))
19567 && accessible_in_template_p (TREE_OPERAND (t, 0),
19568 TREE_OPERAND (t, 1)))
19574 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
19575 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
19578 /* Note that this predicate is not appropriate for general expressions;
19579 only constant expressions (that satisfy potential_constant_expression)
19580 can be tested for value dependence. */
19583 value_dependent_expression_p (tree expression)
19585 if (!processing_template_decl)
19588 /* A name declared with a dependent type. */
19589 if (DECL_P (expression) && type_dependent_expression_p (expression))
19592 switch (TREE_CODE (expression))
19594 case IDENTIFIER_NODE:
19595 /* A name that has not been looked up -- must be dependent. */
19598 case TEMPLATE_PARM_INDEX:
19599 /* A non-type template parm. */
19603 /* A non-type template parm. */
19604 if (DECL_TEMPLATE_PARM_P (expression))
19606 return value_dependent_expression_p (DECL_INITIAL (expression));
19609 /* A constant with literal type and is initialized
19610 with an expression that is value-dependent.
19612 Note that a non-dependent parenthesized initializer will have
19613 already been replaced with its constant value, so if we see
19614 a TREE_LIST it must be dependent. */
19615 if (DECL_INITIAL (expression)
19616 && decl_constant_var_p (expression)
19617 && (TREE_CODE (DECL_INITIAL (expression)) == TREE_LIST
19618 || value_dependent_expression_p (DECL_INITIAL (expression))))
19622 case DYNAMIC_CAST_EXPR:
19623 case STATIC_CAST_EXPR:
19624 case CONST_CAST_EXPR:
19625 case REINTERPRET_CAST_EXPR:
19627 /* These expressions are value-dependent if the type to which
19628 the cast occurs is dependent or the expression being casted
19629 is value-dependent. */
19631 tree type = TREE_TYPE (expression);
19633 if (dependent_type_p (type))
19636 /* A functional cast has a list of operands. */
19637 expression = TREE_OPERAND (expression, 0);
19640 /* If there are no operands, it must be an expression such
19641 as "int()". This should not happen for aggregate types
19642 because it would form non-constant expressions. */
19643 gcc_assert (cxx_dialect >= cxx0x
19644 || INTEGRAL_OR_ENUMERATION_TYPE_P (type));
19649 if (TREE_CODE (expression) == TREE_LIST)
19650 return any_value_dependent_elements_p (expression);
19652 return value_dependent_expression_p (expression);
19656 if (SIZEOF_EXPR_TYPE_P (expression))
19657 return dependent_type_p (TREE_TYPE (TREE_OPERAND (expression, 0)));
19661 /* A `sizeof' expression is value-dependent if the operand is
19662 type-dependent or is a pack expansion. */
19663 expression = TREE_OPERAND (expression, 0);
19664 if (PACK_EXPANSION_P (expression))
19666 else if (TYPE_P (expression))
19667 return dependent_type_p (expression);
19668 return instantiation_dependent_expression_p (expression);
19670 case AT_ENCODE_EXPR:
19671 /* An 'encode' expression is value-dependent if the operand is
19673 expression = TREE_OPERAND (expression, 0);
19674 return dependent_type_p (expression);
19676 case NOEXCEPT_EXPR:
19677 expression = TREE_OPERAND (expression, 0);
19678 return instantiation_dependent_expression_p (expression);
19681 /* All instantiation-dependent expressions should also be considered
19682 value-dependent. */
19683 return instantiation_dependent_scope_ref_p (expression);
19685 case COMPONENT_REF:
19686 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
19687 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
19689 case NONTYPE_ARGUMENT_PACK:
19690 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
19691 is value-dependent. */
19693 tree values = ARGUMENT_PACK_ARGS (expression);
19694 int i, len = TREE_VEC_LENGTH (values);
19696 for (i = 0; i < len; ++i)
19697 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
19705 tree type2 = TRAIT_EXPR_TYPE2 (expression);
19706 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
19707 || (type2 ? dependent_type_p (type2) : false));
19711 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19712 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
19715 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
19716 || (value_dependent_expression_p (TREE_OPERAND (expression, 1))));
19720 tree op = TREE_OPERAND (expression, 0);
19721 return (value_dependent_expression_p (op)
19722 || has_value_dependent_address (op));
19727 tree fn = get_callee_fndecl (expression);
19729 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression)))
19731 nargs = call_expr_nargs (expression);
19732 for (i = 0; i < nargs; ++i)
19734 tree op = CALL_EXPR_ARG (expression, i);
19735 /* In a call to a constexpr member function, look through the
19736 implicit ADDR_EXPR on the object argument so that it doesn't
19737 cause the call to be considered value-dependent. We also
19738 look through it in potential_constant_expression. */
19739 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn)
19740 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
19741 && TREE_CODE (op) == ADDR_EXPR)
19742 op = TREE_OPERAND (op, 0);
19743 if (value_dependent_expression_p (op))
19749 case TEMPLATE_ID_EXPR:
19750 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be
19752 return type_dependent_expression_p (expression);
19758 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val)
19759 if (value_dependent_expression_p (val))
19765 /* Treat a GNU statement expression as dependent to avoid crashing
19766 under fold_non_dependent_expr; it can't be constant. */
19770 /* A constant expression is value-dependent if any subexpression is
19771 value-dependent. */
19772 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
19774 case tcc_reference:
19776 case tcc_comparison:
19778 case tcc_expression:
19781 int i, len = cp_tree_operand_length (expression);
19783 for (i = 0; i < len; i++)
19785 tree t = TREE_OPERAND (expression, i);
19787 /* In some cases, some of the operands may be missing.l
19788 (For example, in the case of PREDECREMENT_EXPR, the
19789 amount to increment by may be missing.) That doesn't
19790 make the expression dependent. */
19791 if (t && value_dependent_expression_p (t))
19802 /* The expression is not value-dependent. */
19806 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
19807 [temp.dep.expr]. Note that an expression with no type is
19808 considered dependent. Other parts of the compiler arrange for an
19809 expression with type-dependent subexpressions to have no type, so
19810 this function doesn't have to be fully recursive. */
19813 type_dependent_expression_p (tree expression)
19815 if (!processing_template_decl)
19818 if (expression == error_mark_node)
19821 /* An unresolved name is always dependent. */
19822 if (TREE_CODE (expression) == IDENTIFIER_NODE
19823 || TREE_CODE (expression) == USING_DECL)
19826 /* Some expression forms are never type-dependent. */
19827 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
19828 || TREE_CODE (expression) == SIZEOF_EXPR
19829 || TREE_CODE (expression) == ALIGNOF_EXPR
19830 || TREE_CODE (expression) == AT_ENCODE_EXPR
19831 || TREE_CODE (expression) == NOEXCEPT_EXPR
19832 || TREE_CODE (expression) == TRAIT_EXPR
19833 || TREE_CODE (expression) == TYPEID_EXPR
19834 || TREE_CODE (expression) == DELETE_EXPR
19835 || TREE_CODE (expression) == VEC_DELETE_EXPR
19836 || TREE_CODE (expression) == THROW_EXPR)
19839 /* The types of these expressions depends only on the type to which
19840 the cast occurs. */
19841 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
19842 || TREE_CODE (expression) == STATIC_CAST_EXPR
19843 || TREE_CODE (expression) == CONST_CAST_EXPR
19844 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
19845 || TREE_CODE (expression) == IMPLICIT_CONV_EXPR
19846 || TREE_CODE (expression) == CAST_EXPR)
19847 return dependent_type_p (TREE_TYPE (expression));
19849 /* The types of these expressions depends only on the type created
19850 by the expression. */
19851 if (TREE_CODE (expression) == NEW_EXPR
19852 || TREE_CODE (expression) == VEC_NEW_EXPR)
19854 /* For NEW_EXPR tree nodes created inside a template, either
19855 the object type itself or a TREE_LIST may appear as the
19857 tree type = TREE_OPERAND (expression, 1);
19858 if (TREE_CODE (type) == TREE_LIST)
19859 /* This is an array type. We need to check array dimensions
19861 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
19862 || value_dependent_expression_p
19863 (TREE_OPERAND (TREE_VALUE (type), 1));
19865 return dependent_type_p (type);
19868 if (TREE_CODE (expression) == SCOPE_REF)
19870 tree scope = TREE_OPERAND (expression, 0);
19871 tree name = TREE_OPERAND (expression, 1);
19873 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it
19874 contains an identifier associated by name lookup with one or more
19875 declarations declared with a dependent type, or...a
19876 nested-name-specifier or qualified-id that names a member of an
19877 unknown specialization. */
19878 return (type_dependent_expression_p (name)
19879 || dependent_scope_p (scope));
19882 if (TREE_CODE (expression) == FUNCTION_DECL
19883 && DECL_LANG_SPECIFIC (expression)
19884 && DECL_TEMPLATE_INFO (expression)
19885 && (any_dependent_template_arguments_p
19886 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
19889 if (TREE_CODE (expression) == TEMPLATE_DECL
19890 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
19893 if (TREE_CODE (expression) == STMT_EXPR)
19894 expression = stmt_expr_value_expr (expression);
19896 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
19901 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
19903 if (type_dependent_expression_p (elt))
19909 /* A static data member of the current instantiation with incomplete
19910 array type is type-dependent, as the definition and specializations
19911 can have different bounds. */
19912 if (TREE_CODE (expression) == VAR_DECL
19913 && DECL_CLASS_SCOPE_P (expression)
19914 && dependent_type_p (DECL_CONTEXT (expression))
19915 && VAR_HAD_UNKNOWN_BOUND (expression))
19918 /* An array of unknown bound depending on a variadic parameter, eg:
19920 template<typename... Args>
19921 void foo (Args... args)
19923 int arr[] = { args... };
19926 template<int... vals>
19929 int arr[] = { vals... };
19932 If the array has no length and has an initializer, it must be that
19933 we couldn't determine its length in cp_complete_array_type because
19934 it is dependent. */
19935 if (TREE_CODE (expression) == VAR_DECL
19936 && TREE_CODE (TREE_TYPE (expression)) == ARRAY_TYPE
19937 && !TYPE_DOMAIN (TREE_TYPE (expression))
19938 && DECL_INITIAL (expression))
19941 if (TREE_TYPE (expression) == unknown_type_node)
19943 if (TREE_CODE (expression) == ADDR_EXPR)
19944 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
19945 if (TREE_CODE (expression) == COMPONENT_REF
19946 || TREE_CODE (expression) == OFFSET_REF)
19948 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
19950 expression = TREE_OPERAND (expression, 1);
19951 if (TREE_CODE (expression) == IDENTIFIER_NODE)
19954 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
19955 if (TREE_CODE (expression) == SCOPE_REF)
19958 if (BASELINK_P (expression))
19959 expression = BASELINK_FUNCTIONS (expression);
19961 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
19963 if (any_dependent_template_arguments_p
19964 (TREE_OPERAND (expression, 1)))
19966 expression = TREE_OPERAND (expression, 0);
19968 gcc_assert (TREE_CODE (expression) == OVERLOAD
19969 || TREE_CODE (expression) == FUNCTION_DECL);
19973 if (type_dependent_expression_p (OVL_CURRENT (expression)))
19975 expression = OVL_NEXT (expression);
19980 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
19982 return (dependent_type_p (TREE_TYPE (expression)));
19985 /* walk_tree callback function for instantiation_dependent_expression_p,
19986 below. Returns non-zero if a dependent subexpression is found. */
19989 instantiation_dependent_r (tree *tp, int *walk_subtrees,
19994 /* We don't have to worry about decltype currently because decltype
19995 of an instantiation-dependent expr is a dependent type. This
19996 might change depending on the resolution of DR 1172. */
19997 *walk_subtrees = false;
20000 enum tree_code code = TREE_CODE (*tp);
20003 /* Don't treat an argument list as dependent just because it has no
20009 case TEMPLATE_PARM_INDEX:
20012 /* Handle expressions with type operands. */
20016 case AT_ENCODE_EXPR:
20018 tree op = TREE_OPERAND (*tp, 0);
20019 if (code == SIZEOF_EXPR && SIZEOF_EXPR_TYPE_P (*tp))
20020 op = TREE_TYPE (op);
20023 if (dependent_type_p (op))
20027 *walk_subtrees = false;
20035 if (dependent_type_p (TRAIT_EXPR_TYPE1 (*tp))
20036 || (TRAIT_EXPR_TYPE2 (*tp)
20037 && dependent_type_p (TRAIT_EXPR_TYPE2 (*tp))))
20039 *walk_subtrees = false;
20042 case COMPONENT_REF:
20043 if (TREE_CODE (TREE_OPERAND (*tp, 1)) == IDENTIFIER_NODE)
20044 /* In a template, finish_class_member_access_expr creates a
20045 COMPONENT_REF with an IDENTIFIER_NODE for op1 even if it isn't
20046 type-dependent, so that we can check access control at
20047 instantiation time (PR 42277). See also Core issue 1273. */
20052 if (instantiation_dependent_scope_ref_p (*tp))
20057 /* Treat statement-expressions as dependent. */
20065 if (type_dependent_expression_p (*tp))
20071 /* Returns TRUE if the EXPRESSION is instantiation-dependent, in the
20072 sense defined by the ABI:
20074 "An expression is instantiation-dependent if it is type-dependent
20075 or value-dependent, or it has a subexpression that is type-dependent
20076 or value-dependent." */
20079 instantiation_dependent_expression_p (tree expression)
20083 if (!processing_template_decl)
20086 if (expression == error_mark_node)
20089 result = cp_walk_tree_without_duplicates (&expression,
20090 instantiation_dependent_r, NULL);
20091 return result != NULL_TREE;
20094 /* Like type_dependent_expression_p, but it also works while not processing
20095 a template definition, i.e. during substitution or mangling. */
20098 type_dependent_expression_p_push (tree expr)
20101 ++processing_template_decl;
20102 b = type_dependent_expression_p (expr);
20103 --processing_template_decl;
20107 /* Returns TRUE if ARGS contains a type-dependent expression. */
20110 any_type_dependent_arguments_p (const vec<tree, va_gc> *args)
20115 FOR_EACH_VEC_SAFE_ELT (args, i, arg)
20117 if (type_dependent_expression_p (arg))
20123 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
20124 expressions) contains any type-dependent expressions. */
20127 any_type_dependent_elements_p (const_tree list)
20129 for (; list; list = TREE_CHAIN (list))
20130 if (type_dependent_expression_p (TREE_VALUE (list)))
20136 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
20137 expressions) contains any value-dependent expressions. */
20140 any_value_dependent_elements_p (const_tree list)
20142 for (; list; list = TREE_CHAIN (list))
20143 if (value_dependent_expression_p (TREE_VALUE (list)))
20149 /* Returns TRUE if the ARG (a template argument) is dependent. */
20152 dependent_template_arg_p (tree arg)
20154 if (!processing_template_decl)
20157 /* Assume a template argument that was wrongly written by the user
20158 is dependent. This is consistent with what
20159 any_dependent_template_arguments_p [that calls this function]
20161 if (!arg || arg == error_mark_node)
20164 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
20165 arg = ARGUMENT_PACK_SELECT_ARG (arg);
20167 if (TREE_CODE (arg) == TEMPLATE_DECL
20168 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
20169 return dependent_template_p (arg);
20170 else if (ARGUMENT_PACK_P (arg))
20172 tree args = ARGUMENT_PACK_ARGS (arg);
20173 int i, len = TREE_VEC_LENGTH (args);
20174 for (i = 0; i < len; ++i)
20176 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
20182 else if (TYPE_P (arg))
20183 return dependent_type_p (arg);
20185 return (type_dependent_expression_p (arg)
20186 || value_dependent_expression_p (arg));
20189 /* Returns true if ARGS (a collection of template arguments) contains
20190 any types that require structural equality testing. */
20193 any_template_arguments_need_structural_equality_p (tree args)
20200 if (args == error_mark_node)
20203 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
20205 tree level = TMPL_ARGS_LEVEL (args, i + 1);
20206 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
20208 tree arg = TREE_VEC_ELT (level, j);
20209 tree packed_args = NULL_TREE;
20212 if (ARGUMENT_PACK_P (arg))
20214 /* Look inside the argument pack. */
20215 packed_args = ARGUMENT_PACK_ARGS (arg);
20216 len = TREE_VEC_LENGTH (packed_args);
20219 for (k = 0; k < len; ++k)
20222 arg = TREE_VEC_ELT (packed_args, k);
20224 if (error_operand_p (arg))
20226 else if (TREE_CODE (arg) == TEMPLATE_DECL
20227 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
20229 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
20231 else if (!TYPE_P (arg) && TREE_TYPE (arg)
20232 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
20241 /* Returns true if ARGS (a collection of template arguments) contains
20242 any dependent arguments. */
20245 any_dependent_template_arguments_p (const_tree args)
20252 if (args == error_mark_node)
20255 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
20257 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
20258 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
20259 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
20266 /* Returns TRUE if the template TMPL is dependent. */
20269 dependent_template_p (tree tmpl)
20271 if (TREE_CODE (tmpl) == OVERLOAD)
20275 if (dependent_template_p (OVL_CURRENT (tmpl)))
20277 tmpl = OVL_NEXT (tmpl);
20282 /* Template template parameters are dependent. */
20283 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
20284 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
20286 /* So are names that have not been looked up. */
20287 if (TREE_CODE (tmpl) == SCOPE_REF
20288 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
20290 /* So are member templates of dependent classes. */
20291 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
20292 return dependent_type_p (DECL_CONTEXT (tmpl));
20296 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
20299 dependent_template_id_p (tree tmpl, tree args)
20301 return (dependent_template_p (tmpl)
20302 || any_dependent_template_arguments_p (args));
20305 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
20309 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
20313 if (!processing_template_decl)
20316 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
20318 tree decl = TREE_VEC_ELT (declv, i);
20319 tree init = TREE_VEC_ELT (initv, i);
20320 tree cond = TREE_VEC_ELT (condv, i);
20321 tree incr = TREE_VEC_ELT (incrv, i);
20323 if (type_dependent_expression_p (decl))
20326 if (init && type_dependent_expression_p (init))
20329 if (type_dependent_expression_p (cond))
20332 if (COMPARISON_CLASS_P (cond)
20333 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
20334 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
20337 if (TREE_CODE (incr) == MODOP_EXPR)
20339 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
20340 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
20343 else if (type_dependent_expression_p (incr))
20345 else if (TREE_CODE (incr) == MODIFY_EXPR)
20347 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
20349 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
20351 tree t = TREE_OPERAND (incr, 1);
20352 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
20353 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
20362 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
20363 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
20364 no such TYPE can be found. Note that this function peers inside
20365 uninstantiated templates and therefore should be used only in
20366 extremely limited situations. ONLY_CURRENT_P restricts this
20367 peering to the currently open classes hierarchy (which is required
20368 when comparing types). */
20371 resolve_typename_type (tree type, bool only_current_p)
20380 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
20382 scope = TYPE_CONTEXT (type);
20383 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
20384 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
20385 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
20386 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
20387 identifier of the TYPENAME_TYPE anymore.
20388 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
20389 TYPENAME_TYPE instead, we avoid messing up with a possible
20390 typedef variant case. */
20391 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
20393 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
20394 it first before we can figure out what NAME refers to. */
20395 if (TREE_CODE (scope) == TYPENAME_TYPE)
20397 if (TYPENAME_IS_RESOLVING_P (scope))
20398 /* Given a class template A with a dependent base with nested type C,
20399 typedef typename A::C::C C will land us here, as trying to resolve
20400 the initial A::C leads to the local C typedef, which leads back to
20401 A::C::C. So we break the recursion now. */
20404 scope = resolve_typename_type (scope, only_current_p);
20406 /* If we don't know what SCOPE refers to, then we cannot resolve the
20408 if (TREE_CODE (scope) == TYPENAME_TYPE)
20410 /* If the SCOPE is a template type parameter, we have no way of
20411 resolving the name. */
20412 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
20414 /* If the SCOPE is not the current instantiation, there's no reason
20415 to look inside it. */
20416 if (only_current_p && !currently_open_class (scope))
20418 /* If this is a typedef, we don't want to look inside (c++/11987). */
20419 if (typedef_variant_p (type))
20421 /* If SCOPE isn't the template itself, it will not have a valid
20422 TYPE_FIELDS list. */
20423 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
20424 /* scope is either the template itself or a compatible instantiation
20425 like X<T>, so look up the name in the original template. */
20426 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
20428 /* scope is a partial instantiation, so we can't do the lookup or we
20429 will lose the template arguments. */
20431 /* Enter the SCOPE so that name lookup will be resolved as if we
20432 were in the class definition. In particular, SCOPE will no
20433 longer be considered a dependent type. */
20434 pushed_scope = push_scope (scope);
20435 /* Look up the declaration. */
20436 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true,
20437 tf_warning_or_error);
20439 result = NULL_TREE;
20441 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
20442 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
20445 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
20446 && TREE_CODE (decl) == TYPE_DECL)
20448 result = TREE_TYPE (decl);
20449 if (result == error_mark_node)
20450 result = NULL_TREE;
20452 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
20453 && DECL_CLASS_TEMPLATE_P (decl))
20457 /* Obtain the template and the arguments. */
20458 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
20459 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
20460 /* Instantiate the template. */
20461 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
20462 /*entering_scope=*/0,
20463 tf_error | tf_user);
20464 if (result == error_mark_node)
20465 result = NULL_TREE;
20468 /* Leave the SCOPE. */
20470 pop_scope (pushed_scope);
20472 /* If we failed to resolve it, return the original typename. */
20476 /* If lookup found a typename type, resolve that too. */
20477 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
20479 /* Ill-formed programs can cause infinite recursion here, so we
20480 must catch that. */
20481 TYPENAME_IS_RESOLVING_P (type) = 1;
20482 result = resolve_typename_type (result, only_current_p);
20483 TYPENAME_IS_RESOLVING_P (type) = 0;
20486 /* Qualify the resulting type. */
20487 quals = cp_type_quals (type);
20489 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
20494 /* EXPR is an expression which is not type-dependent. Return a proxy
20495 for EXPR that can be used to compute the types of larger
20496 expressions containing EXPR. */
20499 build_non_dependent_expr (tree expr)
20503 #ifdef ENABLE_CHECKING
20504 /* Try to get a constant value for all non-dependent expressions in
20505 order to expose bugs in *_dependent_expression_p and constexpr. */
20506 if (cxx_dialect >= cxx0x
20507 && !instantiation_dependent_expression_p (expr))
20508 maybe_constant_value (fold_non_dependent_expr_sfinae (expr, tf_none));
20511 /* Preserve OVERLOADs; the functions must be available to resolve
20514 if (TREE_CODE (inner_expr) == STMT_EXPR)
20515 inner_expr = stmt_expr_value_expr (inner_expr);
20516 if (TREE_CODE (inner_expr) == ADDR_EXPR)
20517 inner_expr = TREE_OPERAND (inner_expr, 0);
20518 if (TREE_CODE (inner_expr) == COMPONENT_REF)
20519 inner_expr = TREE_OPERAND (inner_expr, 1);
20520 if (is_overloaded_fn (inner_expr)
20521 || TREE_CODE (inner_expr) == OFFSET_REF)
20523 /* There is no need to return a proxy for a variable. */
20524 if (TREE_CODE (expr) == VAR_DECL)
20526 /* Preserve string constants; conversions from string constants to
20527 "char *" are allowed, even though normally a "const char *"
20528 cannot be used to initialize a "char *". */
20529 if (TREE_CODE (expr) == STRING_CST)
20531 /* Preserve arithmetic constants, as an optimization -- there is no
20532 reason to create a new node. */
20533 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
20535 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
20536 There is at least one place where we want to know that a
20537 particular expression is a throw-expression: when checking a ?:
20538 expression, there are special rules if the second or third
20539 argument is a throw-expression. */
20540 if (TREE_CODE (expr) == THROW_EXPR)
20543 /* Don't wrap an initializer list, we need to be able to look inside. */
20544 if (BRACE_ENCLOSED_INITIALIZER_P (expr))
20547 /* Don't wrap a dummy object, we need to be able to test for it. */
20548 if (is_dummy_object (expr))
20551 if (TREE_CODE (expr) == COND_EXPR)
20552 return build3 (COND_EXPR,
20554 TREE_OPERAND (expr, 0),
20555 (TREE_OPERAND (expr, 1)
20556 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
20557 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
20558 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
20559 if (TREE_CODE (expr) == COMPOUND_EXPR
20560 && !COMPOUND_EXPR_OVERLOADED (expr))
20561 return build2 (COMPOUND_EXPR,
20563 TREE_OPERAND (expr, 0),
20564 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
20566 /* If the type is unknown, it can't really be non-dependent */
20567 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
20569 /* Otherwise, build a NON_DEPENDENT_EXPR. */
20570 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr);
20573 /* ARGS is a vector of expressions as arguments to a function call.
20574 Replace the arguments with equivalent non-dependent expressions.
20575 This modifies ARGS in place. */
20578 make_args_non_dependent (vec<tree, va_gc> *args)
20583 FOR_EACH_VEC_SAFE_ELT (args, ix, arg)
20585 tree newarg = build_non_dependent_expr (arg);
20587 (*args)[ix] = newarg;
20591 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
20592 with a level one deeper than the actual template parms. */
20597 tree au = cxx_make_type (TEMPLATE_TYPE_PARM);
20598 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
20599 TYPE_DECL, get_identifier ("auto"), au);
20600 TYPE_STUB_DECL (au) = TYPE_NAME (au);
20601 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
20602 (0, processing_template_decl + 1, processing_template_decl + 1,
20603 TYPE_NAME (au), NULL_TREE);
20604 TYPE_CANONICAL (au) = canonical_type_parameter (au);
20605 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
20606 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
20611 /* Given type ARG, return std::initializer_list<ARG>. */
20616 tree std_init_list = namespace_binding
20617 (get_identifier ("initializer_list"), std_node);
20619 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
20621 error ("deducing from brace-enclosed initializer list requires "
20622 "#include <initializer_list>");
20623 return error_mark_node;
20625 argvec = make_tree_vec (1);
20626 TREE_VEC_ELT (argvec, 0) = arg;
20627 return lookup_template_class (std_init_list, argvec, NULL_TREE,
20628 NULL_TREE, 0, tf_warning_or_error);
20631 /* Replace auto in TYPE with std::initializer_list<auto>. */
20634 listify_autos (tree type, tree auto_node)
20636 tree init_auto = listify (auto_node);
20637 tree argvec = make_tree_vec (1);
20638 TREE_VEC_ELT (argvec, 0) = init_auto;
20639 if (processing_template_decl)
20640 argvec = add_to_template_args (current_template_args (), argvec);
20641 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20644 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
20645 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
20648 do_auto_deduction (tree type, tree init, tree auto_node)
20650 tree parms, tparms, targs;
20654 if (init == error_mark_node)
20655 return error_mark_node;
20657 if (type_dependent_expression_p (init))
20658 /* Defining a subset of type-dependent expressions that we can deduce
20659 from ahead of time isn't worth the trouble. */
20662 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
20663 with either a new invented type template parameter U or, if the
20664 initializer is a braced-init-list (8.5.4), with
20665 std::initializer_list<U>. */
20666 if (BRACE_ENCLOSED_INITIALIZER_P (init))
20667 type = listify_autos (type, auto_node);
20669 init = resolve_nondeduced_context (init);
20671 parms = build_tree_list (NULL_TREE, type);
20673 tparms = make_tree_vec (1);
20674 targs = make_tree_vec (1);
20675 TREE_VEC_ELT (tparms, 0)
20676 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
20677 val = type_unification_real (tparms, targs, parms, args, 1, 0,
20678 DEDUCE_CALL, LOOKUP_NORMAL,
20679 NULL, /*explain_p=*/false);
20682 if (processing_template_decl)
20683 /* Try again at instantiation time. */
20685 if (type && type != error_mark_node)
20686 /* If type is error_mark_node a diagnostic must have been
20687 emitted by now. Also, having a mention to '<type error>'
20688 in the diagnostic is not really useful to the user. */
20690 if (cfun && auto_node == current_function_auto_return_pattern
20691 && LAMBDA_FUNCTION_P (current_function_decl))
20692 error ("unable to deduce lambda return type from %qE", init);
20694 error ("unable to deduce %qT from %qE", type, init);
20696 return error_mark_node;
20699 /* If the list of declarators contains more than one declarator, the type
20700 of each declared variable is determined as described above. If the
20701 type deduced for the template parameter U is not the same in each
20702 deduction, the program is ill-formed. */
20703 if (TREE_TYPE (auto_node)
20704 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)))
20706 if (cfun && auto_node == current_function_auto_return_pattern
20707 && LAMBDA_FUNCTION_P (current_function_decl))
20708 error ("inconsistent types %qT and %qT deduced for "
20709 "lambda return type", TREE_TYPE (auto_node),
20710 TREE_VEC_ELT (targs, 0));
20712 error ("inconsistent deduction for %qT: %qT and then %qT",
20713 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0));
20714 return error_mark_node;
20716 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0);
20718 if (processing_template_decl)
20719 targs = add_to_template_args (current_template_args (), targs);
20720 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
20723 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
20727 splice_late_return_type (tree type, tree late_return_type)
20731 if (late_return_type == NULL_TREE)
20733 argvec = make_tree_vec (1);
20734 TREE_VEC_ELT (argvec, 0) = late_return_type;
20735 if (processing_template_parmlist)
20736 /* For a late-specified return type in a template type-parameter, we
20737 need to add a dummy argument level for its parmlist. */
20738 argvec = add_to_template_args
20739 (make_tree_vec (processing_template_parmlist), argvec);
20740 if (current_template_parms)
20741 argvec = add_to_template_args (current_template_args (), argvec);
20742 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
20745 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
20748 is_auto (const_tree type)
20750 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
20751 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
20757 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
20758 appear as a type-specifier for the declaration in question, we don't
20759 have to look through the whole type. */
20762 type_uses_auto (tree type)
20764 enum tree_code code;
20765 if (is_auto (type))
20768 code = TREE_CODE (type);
20770 if (code == POINTER_TYPE || code == REFERENCE_TYPE
20771 || code == OFFSET_TYPE || code == FUNCTION_TYPE
20772 || code == METHOD_TYPE || code == ARRAY_TYPE)
20773 return type_uses_auto (TREE_TYPE (type));
20775 if (TYPE_PTRMEMFUNC_P (type))
20776 return type_uses_auto (TREE_TYPE (TREE_TYPE
20777 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
20782 /* For a given template T, return the vector of typedefs referenced
20783 in T for which access check is needed at T instantiation time.
20784 T is either a FUNCTION_DECL or a RECORD_TYPE.
20785 Those typedefs were added to T by the function
20786 append_type_to_template_for_access_check. */
20788 vec<qualified_typedef_usage_t, va_gc> *
20789 get_types_needing_access_check (tree t)
20792 vec<qualified_typedef_usage_t, va_gc> *result = NULL;
20794 if (!t || t == error_mark_node)
20797 if (!(ti = get_template_info (t)))
20800 if (CLASS_TYPE_P (t)
20801 || TREE_CODE (t) == FUNCTION_DECL)
20803 if (!TI_TEMPLATE (ti))
20806 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
20812 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
20813 tied to T. That list of typedefs will be access checked at
20814 T instantiation time.
20815 T is either a FUNCTION_DECL or a RECORD_TYPE.
20816 TYPE_DECL is a TYPE_DECL node representing a typedef.
20817 SCOPE is the scope through which TYPE_DECL is accessed.
20818 LOCATION is the location of the usage point of TYPE_DECL.
20820 This function is a subroutine of
20821 append_type_to_template_for_access_check. */
20824 append_type_to_template_for_access_check_1 (tree t,
20827 location_t location)
20829 qualified_typedef_usage_t typedef_usage;
20832 if (!t || t == error_mark_node)
20835 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
20836 || CLASS_TYPE_P (t))
20838 && TREE_CODE (type_decl) == TYPE_DECL
20841 if (!(ti = get_template_info (t)))
20844 gcc_assert (TI_TEMPLATE (ti));
20846 typedef_usage.typedef_decl = type_decl;
20847 typedef_usage.context = scope;
20848 typedef_usage.locus = location;
20850 vec_safe_push (TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti), typedef_usage);
20853 /* Append TYPE_DECL to the template TEMPL.
20854 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
20855 At TEMPL instanciation time, TYPE_DECL will be checked to see
20856 if it can be accessed through SCOPE.
20857 LOCATION is the location of the usage point of TYPE_DECL.
20859 e.g. consider the following code snippet:
20866 template<class U> struct S
20868 C::myint mi; // <-- usage point of the typedef C::myint
20873 At S<char> instantiation time, we need to check the access of C::myint
20874 In other words, we need to check the access of the myint typedef through
20875 the C scope. For that purpose, this function will add the myint typedef
20876 and the scope C through which its being accessed to a list of typedefs
20877 tied to the template S. That list will be walked at template instantiation
20878 time and access check performed on each typedefs it contains.
20879 Note that this particular code snippet should yield an error because
20880 myint is private to C. */
20883 append_type_to_template_for_access_check (tree templ,
20886 location_t location)
20888 qualified_typedef_usage_t *iter;
20891 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
20893 /* Make sure we don't append the type to the template twice. */
20894 FOR_EACH_VEC_SAFE_ELT (get_types_needing_access_check (templ), i, iter)
20895 if (iter->typedef_decl == type_decl && scope == iter->context)
20898 append_type_to_template_for_access_check_1 (templ, type_decl,
20902 /* Set up the hash tables for template instantiations. */
20905 init_template_processing (void)
20907 decl_specializations = htab_create_ggc (37,
20908 hash_specialization,
20909 eq_specializations,
20911 type_specializations = htab_create_ggc (37,
20912 hash_specialization,
20913 eq_specializations,
20917 /* Print stats about the template hash tables for -fstats. */
20920 print_template_statistics (void)
20922 fprintf (stderr, "decl_specializations: size %ld, %ld elements, "
20923 "%f collisions\n", (long) htab_size (decl_specializations),
20924 (long) htab_elements (decl_specializations),
20925 htab_collisions (decl_specializations));
20926 fprintf (stderr, "type_specializations: size %ld, %ld elements, "
20927 "%f collisions\n", (long) htab_size (type_specializations),
20928 (long) htab_elements (type_specializations),
20929 htab_collisions (type_specializations));
20932 #include "gt-cp-pt.h"