1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009
4 Free Software Foundation, Inc.
5 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
6 Rewritten by Jason Merrill (jason@cygnus.com).
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
39 #include "cp-objcp-common.h"
40 #include "tree-inline.h"
47 #include "tree-iterator.h"
50 /* The type of functions taking a tree, and some additional data, and
52 typedef int (*tree_fn_t) (tree, void*);
54 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
55 instantiations have been deferred, either because their definitions
56 were not yet available, or because we were putting off doing the work. */
57 struct GTY (()) pending_template {
58 struct pending_template *next;
59 struct tinst_level *tinst;
62 static GTY(()) struct pending_template *pending_templates;
63 static GTY(()) struct pending_template *last_pending_template;
65 int processing_template_parmlist;
66 static int template_header_count;
68 static GTY(()) tree saved_trees;
69 static VEC(int,heap) *inline_parm_levels;
71 static GTY(()) struct tinst_level *current_tinst_level;
73 static GTY(()) tree saved_access_scope;
75 /* Live only within one (recursive) call to tsubst_expr. We use
76 this to pass the statement expression node from the STMT_EXPR
77 to the EXPR_STMT that is its result. */
78 static tree cur_stmt_expr;
80 /* A map from local variable declarations in the body of the template
81 presently being instantiated to the corresponding instantiated
83 static htab_t local_specializations;
85 typedef struct GTY(()) spec_entry
92 static GTY ((param_is (spec_entry)))
93 htab_t decl_specializations;
95 static GTY ((param_is (spec_entry)))
96 htab_t type_specializations;
98 /* Contains canonical template parameter types. The vector is indexed by
99 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a
100 TREE_LIST, whose TREE_VALUEs contain the canonical template
101 parameters of various types and levels. */
102 static GTY(()) VEC(tree,gc) *canonical_template_parms;
104 #define UNIFY_ALLOW_NONE 0
105 #define UNIFY_ALLOW_MORE_CV_QUAL 1
106 #define UNIFY_ALLOW_LESS_CV_QUAL 2
107 #define UNIFY_ALLOW_DERIVED 4
108 #define UNIFY_ALLOW_INTEGER 8
109 #define UNIFY_ALLOW_OUTER_LEVEL 16
110 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
111 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
113 static void push_access_scope (tree);
114 static void pop_access_scope (tree);
115 static bool resolve_overloaded_unification (tree, tree, tree, tree,
116 unification_kind_t, int);
117 static int try_one_overload (tree, tree, tree, tree, tree,
118 unification_kind_t, int, bool);
119 static int unify (tree, tree, tree, tree, int);
120 static void add_pending_template (tree);
121 static int push_tinst_level (tree);
122 static void pop_tinst_level (void);
123 static tree reopen_tinst_level (struct tinst_level *);
124 static tree tsubst_initializer_list (tree, tree);
125 static tree get_class_bindings (tree, tree, tree);
126 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t,
128 static void tsubst_enum (tree, tree, tree);
129 static tree add_to_template_args (tree, tree);
130 static tree add_outermost_template_args (tree, tree);
131 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
132 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*,
134 static int type_unification_real (tree, tree, tree, const tree *,
135 unsigned int, int, unification_kind_t, int);
136 static void note_template_header (int);
137 static tree convert_nontype_argument_function (tree, tree);
138 static tree convert_nontype_argument (tree, tree);
139 static tree convert_template_argument (tree, tree, tree,
140 tsubst_flags_t, int, tree);
141 static int for_each_template_parm (tree, tree_fn_t, void*,
142 struct pointer_set_t*, bool);
143 static tree expand_template_argument_pack (tree);
144 static tree build_template_parm_index (int, int, int, tree, tree);
145 static bool inline_needs_template_parms (tree);
146 static void push_inline_template_parms_recursive (tree, int);
147 static tree retrieve_local_specialization (tree);
148 static void register_local_specialization (tree, tree);
149 static hashval_t hash_specialization (const void *p);
150 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t);
151 static int mark_template_parm (tree, void *);
152 static int template_parm_this_level_p (tree, void *);
153 static tree tsubst_friend_function (tree, tree);
154 static tree tsubst_friend_class (tree, tree);
155 static int can_complete_type_without_circularity (tree);
156 static tree get_bindings (tree, tree, tree, bool);
157 static int template_decl_level (tree);
158 static int check_cv_quals_for_unify (int, tree, tree);
159 static void template_parm_level_and_index (tree, int*, int*);
160 static int unify_pack_expansion (tree, tree, tree, tree, int, bool, bool);
161 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
162 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
163 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
164 static void regenerate_decl_from_template (tree, tree);
165 static tree most_specialized_class (tree, tree);
166 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
167 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
168 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
169 static bool check_specialization_scope (void);
170 static tree process_partial_specialization (tree);
171 static void set_current_access_from_decl (tree);
172 static tree get_template_base (tree, tree, tree, tree);
173 static tree try_class_unification (tree, tree, tree, tree);
174 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
176 static bool template_template_parm_bindings_ok_p (tree, tree);
177 static int template_args_equal (tree, tree);
178 static void tsubst_default_arguments (tree);
179 static tree for_each_template_parm_r (tree *, int *, void *);
180 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
181 static void copy_default_args_to_explicit_spec (tree);
182 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
183 static int eq_local_specializations (const void *, const void *);
184 static bool dependent_template_arg_p (tree);
185 static bool any_template_arguments_need_structural_equality_p (tree);
186 static bool dependent_type_p_r (tree);
187 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool);
188 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
189 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree);
190 static tree tsubst_decl (tree, tree, tsubst_flags_t);
191 static void perform_typedefs_access_check (tree tmpl, tree targs);
192 static void append_type_to_template_for_access_check_1 (tree, tree, tree);
193 static hashval_t iterative_hash_template_arg (tree arg, hashval_t val);
195 /* Make the current scope suitable for access checking when we are
196 processing T. T can be FUNCTION_DECL for instantiated function
197 template, or VAR_DECL for static member variable (need by
198 instantiate_decl). */
201 push_access_scope (tree t)
203 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
204 || TREE_CODE (t) == VAR_DECL);
206 if (DECL_FRIEND_CONTEXT (t))
207 push_nested_class (DECL_FRIEND_CONTEXT (t));
208 else if (DECL_CLASS_SCOPE_P (t))
209 push_nested_class (DECL_CONTEXT (t));
211 push_to_top_level ();
213 if (TREE_CODE (t) == FUNCTION_DECL)
215 saved_access_scope = tree_cons
216 (NULL_TREE, current_function_decl, saved_access_scope);
217 current_function_decl = t;
221 /* Restore the scope set up by push_access_scope. T is the node we
225 pop_access_scope (tree t)
227 if (TREE_CODE (t) == FUNCTION_DECL)
229 current_function_decl = TREE_VALUE (saved_access_scope);
230 saved_access_scope = TREE_CHAIN (saved_access_scope);
233 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
236 pop_from_top_level ();
239 /* Do any processing required when DECL (a member template
240 declaration) is finished. Returns the TEMPLATE_DECL corresponding
241 to DECL, unless it is a specialization, in which case the DECL
242 itself is returned. */
245 finish_member_template_decl (tree decl)
247 if (decl == error_mark_node)
248 return error_mark_node;
250 gcc_assert (DECL_P (decl));
252 if (TREE_CODE (decl) == TYPE_DECL)
256 type = TREE_TYPE (decl);
257 if (type == error_mark_node)
258 return error_mark_node;
259 if (MAYBE_CLASS_TYPE_P (type)
260 && CLASSTYPE_TEMPLATE_INFO (type)
261 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
263 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
264 check_member_template (tmpl);
269 else if (TREE_CODE (decl) == FIELD_DECL)
270 error ("data member %qD cannot be a member template", decl);
271 else if (DECL_TEMPLATE_INFO (decl))
273 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
275 check_member_template (DECL_TI_TEMPLATE (decl));
276 return DECL_TI_TEMPLATE (decl);
282 error ("invalid member template declaration %qD", decl);
284 return error_mark_node;
287 /* Return the template info node corresponding to T, whatever T is. */
290 get_template_info (tree t)
292 tree tinfo = NULL_TREE;
294 if (DECL_P (t) && DECL_LANG_SPECIFIC (t))
295 tinfo = DECL_TEMPLATE_INFO (t);
297 if (!tinfo && TREE_CODE (t) == TYPE_DECL)
300 if (TAGGED_TYPE_P (t))
301 tinfo = TYPE_TEMPLATE_INFO (t);
306 /* Returns the template nesting level of the indicated class TYPE.
316 A<T>::B<U> has depth two, while A<T> has depth one.
317 Both A<T>::B<int> and A<int>::B<U> have depth one, if
318 they are instantiations, not specializations.
320 This function is guaranteed to return 0 if passed NULL_TREE so
321 that, for example, `template_class_depth (current_class_type)' is
325 template_class_depth (tree type)
330 type && TREE_CODE (type) != NAMESPACE_DECL;
331 type = (TREE_CODE (type) == FUNCTION_DECL)
332 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
334 tree tinfo = get_template_info (type);
336 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo))
337 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo))))
344 /* Subroutine of maybe_begin_member_template_processing.
345 Returns true if processing DECL needs us to push template parms. */
348 inline_needs_template_parms (tree decl)
350 if (! DECL_TEMPLATE_INFO (decl))
353 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
354 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
357 /* Subroutine of maybe_begin_member_template_processing.
358 Push the template parms in PARMS, starting from LEVELS steps into the
359 chain, and ending at the beginning, since template parms are listed
363 push_inline_template_parms_recursive (tree parmlist, int levels)
365 tree parms = TREE_VALUE (parmlist);
369 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
371 ++processing_template_decl;
372 current_template_parms
373 = tree_cons (size_int (processing_template_decl),
374 parms, current_template_parms);
375 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
377 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
379 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
381 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
383 if (parm == error_mark_node)
386 gcc_assert (DECL_P (parm));
388 switch (TREE_CODE (parm))
397 /* Make a CONST_DECL as is done in process_template_parm.
398 It is ugly that we recreate this here; the original
399 version built in process_template_parm is no longer
401 tree decl = build_decl (DECL_SOURCE_LOCATION (parm),
402 CONST_DECL, DECL_NAME (parm),
404 DECL_ARTIFICIAL (decl) = 1;
405 TREE_CONSTANT (decl) = 1;
406 TREE_READONLY (decl) = 1;
407 DECL_INITIAL (decl) = DECL_INITIAL (parm);
408 SET_DECL_TEMPLATE_PARM_P (decl);
419 /* Restore the template parameter context for a member template or
420 a friend template defined in a class definition. */
423 maybe_begin_member_template_processing (tree decl)
428 if (inline_needs_template_parms (decl))
430 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
431 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
433 if (DECL_TEMPLATE_SPECIALIZATION (decl))
436 parms = TREE_CHAIN (parms);
439 push_inline_template_parms_recursive (parms, levels);
442 /* Remember how many levels of template parameters we pushed so that
443 we can pop them later. */
444 VEC_safe_push (int, heap, inline_parm_levels, levels);
447 /* Undo the effects of maybe_begin_member_template_processing. */
450 maybe_end_member_template_processing (void)
455 if (VEC_length (int, inline_parm_levels) == 0)
458 last = VEC_pop (int, inline_parm_levels);
459 for (i = 0; i < last; ++i)
461 --processing_template_decl;
462 current_template_parms = TREE_CHAIN (current_template_parms);
467 /* Return a new template argument vector which contains all of ARGS,
468 but has as its innermost set of arguments the EXTRA_ARGS. */
471 add_to_template_args (tree args, tree extra_args)
478 extra_depth = TMPL_ARGS_DEPTH (extra_args);
479 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
481 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
482 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
484 for (j = 1; j <= extra_depth; ++j, ++i)
485 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
490 /* Like add_to_template_args, but only the outermost ARGS are added to
491 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
492 (EXTRA_ARGS) levels are added. This function is used to combine
493 the template arguments from a partial instantiation with the
494 template arguments used to attain the full instantiation from the
495 partial instantiation. */
498 add_outermost_template_args (tree args, tree extra_args)
502 /* If there are more levels of EXTRA_ARGS than there are ARGS,
503 something very fishy is going on. */
504 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
506 /* If *all* the new arguments will be the EXTRA_ARGS, just return
508 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
511 /* For the moment, we make ARGS look like it contains fewer levels. */
512 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
514 new_args = add_to_template_args (args, extra_args);
516 /* Now, we restore ARGS to its full dimensions. */
517 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
522 /* Return the N levels of innermost template arguments from the ARGS. */
525 get_innermost_template_args (tree args, int n)
533 /* If N is 1, just return the innermost set of template arguments. */
535 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
537 /* If we're not removing anything, just return the arguments we were
539 extra_levels = TMPL_ARGS_DEPTH (args) - n;
540 gcc_assert (extra_levels >= 0);
541 if (extra_levels == 0)
544 /* Make a new set of arguments, not containing the outer arguments. */
545 new_args = make_tree_vec (n);
546 for (i = 1; i <= n; ++i)
547 SET_TMPL_ARGS_LEVEL (new_args, i,
548 TMPL_ARGS_LEVEL (args, i + extra_levels));
553 /* The inverse of get_innermost_template_args: Return all but the innermost
554 EXTRA_LEVELS levels of template arguments from the ARGS. */
557 strip_innermost_template_args (tree args, int extra_levels)
560 int n = TMPL_ARGS_DEPTH (args) - extra_levels;
565 /* If N is 1, just return the outermost set of template arguments. */
567 return TMPL_ARGS_LEVEL (args, 1);
569 /* If we're not removing anything, just return the arguments we were
571 gcc_assert (extra_levels >= 0);
572 if (extra_levels == 0)
575 /* Make a new set of arguments, not containing the inner arguments. */
576 new_args = make_tree_vec (n);
577 for (i = 1; i <= n; ++i)
578 SET_TMPL_ARGS_LEVEL (new_args, i,
579 TMPL_ARGS_LEVEL (args, i));
584 /* We've got a template header coming up; push to a new level for storing
588 begin_template_parm_list (void)
590 /* We use a non-tag-transparent scope here, which causes pushtag to
591 put tags in this scope, rather than in the enclosing class or
592 namespace scope. This is the right thing, since we want
593 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
594 global template class, push_template_decl handles putting the
595 TEMPLATE_DECL into top-level scope. For a nested template class,
598 template <class T> struct S1 {
599 template <class T> struct S2 {};
602 pushtag contains special code to call pushdecl_with_scope on the
603 TEMPLATE_DECL for S2. */
604 begin_scope (sk_template_parms, NULL);
605 ++processing_template_decl;
606 ++processing_template_parmlist;
607 note_template_header (0);
610 /* This routine is called when a specialization is declared. If it is
611 invalid to declare a specialization here, an error is reported and
612 false is returned, otherwise this routine will return true. */
615 check_specialization_scope (void)
617 tree scope = current_scope ();
621 An explicit specialization shall be declared in the namespace of
622 which the template is a member, or, for member templates, in the
623 namespace of which the enclosing class or enclosing class
624 template is a member. An explicit specialization of a member
625 function, member class or static data member of a class template
626 shall be declared in the namespace of which the class template
628 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
630 error ("explicit specialization in non-namespace scope %qD", scope);
636 In an explicit specialization declaration for a member of a class
637 template or a member template that appears in namespace scope,
638 the member template and some of its enclosing class templates may
639 remain unspecialized, except that the declaration shall not
640 explicitly specialize a class member template if its enclosing
641 class templates are not explicitly specialized as well. */
642 if (current_template_parms)
644 error ("enclosing class templates are not explicitly specialized");
651 /* We've just seen template <>. */
654 begin_specialization (void)
656 begin_scope (sk_template_spec, NULL);
657 note_template_header (1);
658 return check_specialization_scope ();
661 /* Called at then end of processing a declaration preceded by
665 end_specialization (void)
668 reset_specialization ();
671 /* Any template <>'s that we have seen thus far are not referring to a
672 function specialization. */
675 reset_specialization (void)
677 processing_specialization = 0;
678 template_header_count = 0;
681 /* We've just seen a template header. If SPECIALIZATION is nonzero,
682 it was of the form template <>. */
685 note_template_header (int specialization)
687 processing_specialization = specialization;
688 template_header_count++;
691 /* We're beginning an explicit instantiation. */
694 begin_explicit_instantiation (void)
696 gcc_assert (!processing_explicit_instantiation);
697 processing_explicit_instantiation = true;
702 end_explicit_instantiation (void)
704 gcc_assert (processing_explicit_instantiation);
705 processing_explicit_instantiation = false;
708 /* An explicit specialization or partial specialization TMPL is being
709 declared. Check that the namespace in which the specialization is
710 occurring is permissible. Returns false iff it is invalid to
711 specialize TMPL in the current namespace. */
714 check_specialization_namespace (tree tmpl)
716 tree tpl_ns = decl_namespace_context (tmpl);
720 An explicit specialization shall be declared in the namespace of
721 which the template is a member, or, for member templates, in the
722 namespace of which the enclosing class or enclosing class
723 template is a member. An explicit specialization of a member
724 function, member class or static data member of a class template
725 shall be declared in the namespace of which the class template is
727 if (is_associated_namespace (current_namespace, tpl_ns))
728 /* Same or super-using namespace. */
732 permerror (input_location, "specialization of %qD in different namespace", tmpl);
733 permerror (input_location, " from definition of %q+#D", tmpl);
738 /* SPEC is an explicit instantiation. Check that it is valid to
739 perform this explicit instantiation in the current namespace. */
742 check_explicit_instantiation_namespace (tree spec)
746 /* DR 275: An explicit instantiation shall appear in an enclosing
747 namespace of its template. */
748 ns = decl_namespace_context (spec);
749 if (!is_ancestor (current_namespace, ns))
750 permerror (input_location, "explicit instantiation of %qD in namespace %qD "
751 "(which does not enclose namespace %qD)",
752 spec, current_namespace, ns);
755 /* The TYPE is being declared. If it is a template type, that means it
756 is a partial specialization. Do appropriate error-checking. */
759 maybe_process_partial_specialization (tree type)
763 if (type == error_mark_node)
764 return error_mark_node;
766 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
768 error ("name of class shadows template template parameter %qD",
770 return error_mark_node;
773 context = TYPE_CONTEXT (type);
775 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
777 /* This is for ordinary explicit specialization and partial
778 specialization of a template class such as:
780 template <> class C<int>;
784 template <class T> class C<T*>;
786 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
788 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
789 && !COMPLETE_TYPE_P (type))
791 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
792 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
793 if (processing_template_decl)
795 if (push_template_decl (TYPE_MAIN_DECL (type))
797 return error_mark_node;
800 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
801 error ("specialization of %qT after instantiation", type);
803 else if (CLASS_TYPE_P (type)
804 && !CLASSTYPE_USE_TEMPLATE (type)
805 && CLASSTYPE_TEMPLATE_INFO (type)
806 && context && CLASS_TYPE_P (context)
807 && CLASSTYPE_TEMPLATE_INFO (context))
809 /* This is for an explicit specialization of member class
810 template according to [temp.expl.spec/18]:
812 template <> template <class U> class C<int>::D;
814 The context `C<int>' must be an implicit instantiation.
815 Otherwise this is just a member class template declared
818 template <> class C<int> { template <class U> class D; };
819 template <> template <class U> class C<int>::D;
821 In the first case, `C<int>::D' is a specialization of `C<T>::D'
822 while in the second case, `C<int>::D' is a primary template
823 and `C<T>::D' may not exist. */
825 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
826 && !COMPLETE_TYPE_P (type))
829 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
831 if (current_namespace
832 != decl_namespace_context (tmpl))
834 permerror (input_location, "specializing %q#T in different namespace", type);
835 permerror (input_location, " from definition of %q+#D", tmpl);
838 /* Check for invalid specialization after instantiation:
840 template <> template <> class C<int>::D<int>;
841 template <> template <class U> class C<int>::D; */
843 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl);
844 t; t = TREE_CHAIN (t))
846 tree inst = TREE_VALUE (t);
847 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst))
849 /* We already have a full specialization of this partial
850 instantiation. Reassign it to the new member
851 specialization template. */
855 elt.tmpl = most_general_template (tmpl);
856 elt.args = CLASSTYPE_TI_ARGS (inst);
859 htab_remove_elt (type_specializations, &elt);
862 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args);
864 slot = (spec_entry **)
865 htab_find_slot (type_specializations, &elt, INSERT);
866 *slot = GGC_NEW (spec_entry);
869 else if (COMPLETE_TYPE_P (inst) || TYPE_BEING_DEFINED (inst))
870 /* But if we've had an implicit instantiation, that's a
871 problem ([temp.expl.spec]/6). */
872 error ("specialization %qT after instantiation %qT",
876 /* Mark TYPE as a specialization. And as a result, we only
877 have one level of template argument for the innermost
879 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
880 CLASSTYPE_TI_ARGS (type)
881 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
884 else if (processing_specialization)
886 error ("explicit specialization of non-template %qT", type);
887 return error_mark_node;
893 /* Returns nonzero if we can optimize the retrieval of specializations
894 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
895 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
898 optimize_specialization_lookup_p (tree tmpl)
900 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
901 && DECL_CLASS_SCOPE_P (tmpl)
902 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
904 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
905 /* The optimized lookup depends on the fact that the
906 template arguments for the member function template apply
907 purely to the containing class, which is not true if the
908 containing class is an explicit or partial
910 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
911 && !DECL_MEMBER_TEMPLATE_P (tmpl)
912 && !DECL_CONV_FN_P (tmpl)
913 /* It is possible to have a template that is not a member
914 template and is not a member of a template class:
916 template <typename T>
917 struct S { friend A::f(); };
919 Here, the friend function is a template, but the context does
920 not have template information. The optimized lookup relies
921 on having ARGS be the template arguments for both the class
922 and the function template. */
923 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
926 /* Retrieve the specialization (in the sense of [temp.spec] - a
927 specialization is either an instantiation or an explicit
928 specialization) of TMPL for the given template ARGS. If there is
929 no such specialization, return NULL_TREE. The ARGS are a vector of
930 arguments, or a vector of vectors of arguments, in the case of
931 templates with more than one level of parameters.
933 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
934 then we search for a partial specialization matching ARGS. This
935 parameter is ignored if TMPL is not a class template. */
938 retrieve_specialization (tree tmpl, tree args, hashval_t hash)
940 if (args == error_mark_node)
943 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
945 /* There should be as many levels of arguments as there are
946 levels of parameters. */
947 gcc_assert (TMPL_ARGS_DEPTH (args)
948 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
950 if (optimize_specialization_lookup_p (tmpl))
953 tree class_specialization;
954 VEC(tree,gc) *methods;
958 /* The template arguments actually apply to the containing
959 class. Find the class specialization with those
961 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
963 = retrieve_specialization (class_template, args, 0);
964 if (!class_specialization)
966 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
967 for the specialization. */
968 idx = class_method_index_for_fn (class_specialization, tmpl);
971 /* Iterate through the methods with the indicated name, looking
972 for the one that has an instance of TMPL. */
973 methods = CLASSTYPE_METHOD_VEC (class_specialization);
974 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
976 tree fn = OVL_CURRENT (fns);
977 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl
978 /* using-declarations can add base methods to the method vec,
979 and we don't want those here. */
980 && DECL_CONTEXT (fn) == class_specialization)
989 htab_t specializations;
993 elt.spec = NULL_TREE;
995 if (DECL_CLASS_TEMPLATE_P (tmpl))
996 specializations = type_specializations;
998 specializations = decl_specializations;
1001 hash = hash_specialization (&elt);
1002 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1010 /* Like retrieve_specialization, but for local declarations. */
1013 retrieve_local_specialization (tree tmpl)
1017 if (local_specializations == NULL)
1020 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1021 htab_hash_pointer (tmpl));
1022 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1025 /* Returns nonzero iff DECL is a specialization of TMPL. */
1028 is_specialization_of (tree decl, tree tmpl)
1032 if (TREE_CODE (decl) == FUNCTION_DECL)
1036 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1042 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1044 for (t = TREE_TYPE (decl);
1046 t = CLASSTYPE_USE_TEMPLATE (t)
1047 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1048 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1055 /* Returns nonzero iff DECL is a specialization of friend declaration
1056 FRIEND_DECL according to [temp.friend]. */
1059 is_specialization_of_friend (tree decl, tree friend_decl)
1061 bool need_template = true;
1064 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1065 || TREE_CODE (decl) == TYPE_DECL);
1067 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1068 of a template class, we want to check if DECL is a specialization
1070 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1071 && DECL_TEMPLATE_INFO (friend_decl)
1072 && !DECL_USE_TEMPLATE (friend_decl))
1074 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1075 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1076 need_template = false;
1078 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1079 && !PRIMARY_TEMPLATE_P (friend_decl))
1080 need_template = false;
1082 /* There is nothing to do if this is not a template friend. */
1083 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1086 if (is_specialization_of (decl, friend_decl))
1090 A member of a class template may be declared to be a friend of a
1091 non-template class. In this case, the corresponding member of
1092 every specialization of the class template is a friend of the
1093 class granting friendship.
1095 For example, given a template friend declaration
1097 template <class T> friend void A<T>::f();
1099 the member function below is considered a friend
1101 template <> struct A<int> {
1105 For this type of template friend, TEMPLATE_DEPTH below will be
1106 nonzero. To determine if DECL is a friend of FRIEND, we first
1107 check if the enclosing class is a specialization of another. */
1109 template_depth = template_class_depth (DECL_CONTEXT (friend_decl));
1111 && DECL_CLASS_SCOPE_P (decl)
1112 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1113 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1115 /* Next, we check the members themselves. In order to handle
1116 a few tricky cases, such as when FRIEND_DECL's are
1118 template <class T> friend void A<T>::g(T t);
1119 template <class T> template <T t> friend void A<T>::h();
1123 void A<int>::g(int);
1124 template <int> void A<int>::h();
1126 we need to figure out ARGS, the template arguments from
1127 the context of DECL. This is required for template substitution
1128 of `T' in the function parameter of `g' and template parameter
1129 of `h' in the above examples. Here ARGS corresponds to `int'. */
1131 tree context = DECL_CONTEXT (decl);
1132 tree args = NULL_TREE;
1133 int current_depth = 0;
1135 while (current_depth < template_depth)
1137 if (CLASSTYPE_TEMPLATE_INFO (context))
1139 if (current_depth == 0)
1140 args = TYPE_TI_ARGS (context);
1142 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1145 context = TYPE_CONTEXT (context);
1148 if (TREE_CODE (decl) == FUNCTION_DECL)
1153 tree friend_args_type;
1154 tree decl_args_type;
1156 /* Make sure that both DECL and FRIEND_DECL are templates or
1158 is_template = DECL_TEMPLATE_INFO (decl)
1159 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1160 if (need_template ^ is_template)
1162 else if (is_template)
1164 /* If both are templates, check template parameter list. */
1166 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1168 if (!comp_template_parms
1169 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1173 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1176 decl_type = TREE_TYPE (decl);
1178 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1179 tf_none, NULL_TREE);
1180 if (friend_type == error_mark_node)
1183 /* Check if return types match. */
1184 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1187 /* Check if function parameter types match, ignoring the
1188 `this' parameter. */
1189 friend_args_type = TYPE_ARG_TYPES (friend_type);
1190 decl_args_type = TYPE_ARG_TYPES (decl_type);
1191 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1192 friend_args_type = TREE_CHAIN (friend_args_type);
1193 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1194 decl_args_type = TREE_CHAIN (decl_args_type);
1196 return compparms (decl_args_type, friend_args_type);
1200 /* DECL is a TYPE_DECL */
1202 tree decl_type = TREE_TYPE (decl);
1204 /* Make sure that both DECL and FRIEND_DECL are templates or
1207 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1208 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1210 if (need_template ^ is_template)
1212 else if (is_template)
1215 /* If both are templates, check the name of the two
1216 TEMPLATE_DECL's first because is_friend didn't. */
1217 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1218 != DECL_NAME (friend_decl))
1221 /* Now check template parameter list. */
1223 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1225 return comp_template_parms
1226 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1230 return (DECL_NAME (decl)
1231 == DECL_NAME (friend_decl));
1237 /* Register the specialization SPEC as a specialization of TMPL with
1238 the indicated ARGS. IS_FRIEND indicates whether the specialization
1239 is actually just a friend declaration. Returns SPEC, or an
1240 equivalent prior declaration, if available. */
1243 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1247 spec_entry **slot = NULL;
1250 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1252 if (TREE_CODE (spec) == FUNCTION_DECL
1253 && uses_template_parms (DECL_TI_ARGS (spec)))
1254 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1255 register it; we want the corresponding TEMPLATE_DECL instead.
1256 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1257 the more obvious `uses_template_parms (spec)' to avoid problems
1258 with default function arguments. In particular, given
1259 something like this:
1261 template <class T> void f(T t1, T t = T())
1263 the default argument expression is not substituted for in an
1264 instantiation unless and until it is actually needed. */
1267 if (optimize_specialization_lookup_p (tmpl))
1268 /* We don't put these specializations in the hash table, but we might
1269 want to give an error about a mismatch. */
1270 fn = retrieve_specialization (tmpl, args, 0);
1278 hash = hash_specialization (&elt);
1280 slot = (spec_entry **)
1281 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1288 /* We can sometimes try to re-register a specialization that we've
1289 already got. In particular, regenerate_decl_from_template calls
1290 duplicate_decls which will update the specialization list. But,
1291 we'll still get called again here anyhow. It's more convenient
1292 to simply allow this than to try to prevent it. */
1295 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1297 if (DECL_TEMPLATE_INSTANTIATION (fn))
1299 if (DECL_ODR_USED (fn)
1300 || DECL_EXPLICIT_INSTANTIATION (fn))
1302 error ("specialization of %qD after instantiation",
1304 return error_mark_node;
1309 /* This situation should occur only if the first
1310 specialization is an implicit instantiation, the
1311 second is an explicit specialization, and the
1312 implicit instantiation has not yet been used. That
1313 situation can occur if we have implicitly
1314 instantiated a member function and then specialized
1317 We can also wind up here if a friend declaration that
1318 looked like an instantiation turns out to be a
1321 template <class T> void foo(T);
1322 class S { friend void foo<>(int) };
1323 template <> void foo(int);
1325 We transform the existing DECL in place so that any
1326 pointers to it become pointers to the updated
1329 If there was a definition for the template, but not
1330 for the specialization, we want this to look as if
1331 there were no definition, and vice versa. */
1332 DECL_INITIAL (fn) = NULL_TREE;
1333 duplicate_decls (spec, fn, is_friend);
1334 /* The call to duplicate_decls will have applied
1337 An explicit specialization of a function template
1338 is inline only if it is explicitly declared to be,
1339 and independently of whether its function template
1342 to the primary function; now copy the inline bits to
1343 the various clones. */
1344 FOR_EACH_CLONE (clone, fn)
1345 DECL_DECLARED_INLINE_P (clone)
1346 = DECL_DECLARED_INLINE_P (fn);
1347 check_specialization_namespace (fn);
1352 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1354 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1355 /* Dup decl failed, but this is a new definition. Set the
1356 line number so any errors match this new
1358 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1364 return duplicate_decls (spec, fn, is_friend);
1366 /* A specialization must be declared in the same namespace as the
1367 template it is specializing. */
1368 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1369 && !check_specialization_namespace (tmpl))
1370 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1372 if (!optimize_specialization_lookup_p (tmpl))
1374 gcc_assert (tmpl && args && spec);
1375 *slot = GGC_NEW (spec_entry);
1377 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1378 && PRIMARY_TEMPLATE_P (tmpl)
1379 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1380 /* TMPL is a forward declaration of a template function; keep a list
1381 of all specializations in case we need to reassign them to a friend
1382 template later in tsubst_friend_function. */
1383 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1384 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1390 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1391 TMPL and ARGS members, ignores SPEC. */
1394 eq_specializations (const void *p1, const void *p2)
1396 const spec_entry *e1 = (const spec_entry *)p1;
1397 const spec_entry *e2 = (const spec_entry *)p2;
1399 return (e1->tmpl == e2->tmpl
1400 && comp_template_args (e1->args, e2->args));
1403 /* Returns a hash for a template TMPL and template arguments ARGS. */
1406 hash_tmpl_and_args (tree tmpl, tree args)
1408 hashval_t val = DECL_UID (tmpl);
1409 return iterative_hash_template_arg (args, val);
1412 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1416 hash_specialization (const void *p)
1418 const spec_entry *e = (const spec_entry *)p;
1419 return hash_tmpl_and_args (e->tmpl, e->args);
1422 /* Recursively calculate a hash value for a template argument ARG, for use
1423 in the hash tables of template specializations. */
1426 iterative_hash_template_arg (tree arg, hashval_t val)
1428 unsigned HOST_WIDE_INT i;
1429 enum tree_code code;
1432 if (arg == NULL_TREE)
1433 return iterative_hash_object (arg, val);
1438 code = TREE_CODE (arg);
1439 tclass = TREE_CODE_CLASS (code);
1441 val = iterative_hash_object (code, val);
1448 case IDENTIFIER_NODE:
1449 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1453 int i, len = TREE_VEC_LENGTH (arg);
1454 for (i = 0; i < len; ++i)
1455 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1459 case TYPE_PACK_EXPANSION:
1460 case EXPR_PACK_EXPANSION:
1461 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1463 case ARGUMENT_PACK_SELECT:
1464 /* We can get one of these when re-hashing a previous entry in the middle
1465 of substituting into a pack expansion. Just look through it... */
1466 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1467 /* ...and fall through. */
1468 case TYPE_ARGUMENT_PACK:
1469 case NONTYPE_ARGUMENT_PACK:
1470 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1473 for (; arg; arg = TREE_CHAIN (arg))
1474 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1478 for (; arg; arg = OVL_CHAIN (arg))
1479 val = iterative_hash_template_arg (OVL_FUNCTION (arg), val);
1485 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1487 val = iterative_hash_template_arg (field, val);
1488 val = iterative_hash_template_arg (value, val);
1494 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1495 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1498 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1501 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1502 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1504 case TEMPLATE_PARM_INDEX:
1505 val = iterative_hash_template_arg
1506 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1507 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1508 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1511 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1512 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1513 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1516 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1518 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1522 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1523 code = TREE_CODE (TREE_OPERAND (arg, 1));
1524 val = iterative_hash_object (code, val);
1525 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1531 if (TYPE_CANONICAL (arg))
1532 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1534 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1535 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1536 /* Otherwise just compare the types during lookup. */
1539 case tcc_declaration:
1541 return iterative_hash_expr (arg, val);
1544 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1546 unsigned n = TREE_OPERAND_LENGTH (arg);
1547 for (i = 0; i < n; ++i)
1548 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1557 /* Unregister the specialization SPEC as a specialization of TMPL.
1558 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1559 if the SPEC was listed as a specialization of TMPL.
1561 Note that SPEC has been ggc_freed, so we can't look inside it. */
1564 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1569 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1570 elt.args = TI_ARGS (tinfo);
1571 elt.spec = NULL_TREE;
1573 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1576 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1577 gcc_assert (new_spec != NULL_TREE);
1578 (*slot)->spec = new_spec;
1585 /* Compare an entry in the local specializations hash table P1 (which
1586 is really a pointer to a TREE_LIST) with P2 (which is really a
1590 eq_local_specializations (const void *p1, const void *p2)
1592 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1595 /* Hash P1, an entry in the local specializations table. */
1598 hash_local_specialization (const void* p1)
1600 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1603 /* Like register_specialization, but for local declarations. We are
1604 registering SPEC, an instantiation of TMPL. */
1607 register_local_specialization (tree spec, tree tmpl)
1611 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1612 htab_hash_pointer (tmpl), INSERT);
1613 *slot = build_tree_list (spec, tmpl);
1616 /* TYPE is a class type. Returns true if TYPE is an explicitly
1617 specialized class. */
1620 explicit_class_specialization_p (tree type)
1622 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1624 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1627 /* Print the list of candidate FNS in an error message. */
1630 print_candidates (tree fns)
1634 const char *str = "candidates are:";
1636 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1640 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1641 error ("%s %+#D", str, OVL_CURRENT (f));
1646 /* Returns the template (one of the functions given by TEMPLATE_ID)
1647 which can be specialized to match the indicated DECL with the
1648 explicit template args given in TEMPLATE_ID. The DECL may be
1649 NULL_TREE if none is available. In that case, the functions in
1650 TEMPLATE_ID are non-members.
1652 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1653 specialization of a member template.
1655 The TEMPLATE_COUNT is the number of references to qualifying
1656 template classes that appeared in the name of the function. See
1657 check_explicit_specialization for a more accurate description.
1659 TSK indicates what kind of template declaration (if any) is being
1660 declared. TSK_TEMPLATE indicates that the declaration given by
1661 DECL, though a FUNCTION_DECL, has template parameters, and is
1662 therefore a template function.
1664 The template args (those explicitly specified and those deduced)
1665 are output in a newly created vector *TARGS_OUT.
1667 If it is impossible to determine the result, an error message is
1668 issued. The error_mark_node is returned to indicate failure. */
1671 determine_specialization (tree template_id,
1674 int need_member_template,
1680 tree explicit_targs;
1681 tree candidates = NULL_TREE;
1682 /* A TREE_LIST of templates of which DECL may be a specialization.
1683 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1684 corresponding TREE_PURPOSE is the set of template arguments that,
1685 when used to instantiate the template, would produce a function
1686 with the signature of DECL. */
1687 tree templates = NULL_TREE;
1689 struct cp_binding_level *b;
1691 *targs_out = NULL_TREE;
1693 if (template_id == error_mark_node || decl == error_mark_node)
1694 return error_mark_node;
1696 fns = TREE_OPERAND (template_id, 0);
1697 explicit_targs = TREE_OPERAND (template_id, 1);
1699 if (fns == error_mark_node)
1700 return error_mark_node;
1702 /* Check for baselinks. */
1703 if (BASELINK_P (fns))
1704 fns = BASELINK_FUNCTIONS (fns);
1706 if (!is_overloaded_fn (fns))
1708 error ("%qD is not a function template", fns);
1709 return error_mark_node;
1712 /* Count the number of template headers specified for this
1715 for (b = current_binding_level;
1716 b->kind == sk_template_parms;
1720 for (; fns; fns = OVL_NEXT (fns))
1722 tree fn = OVL_CURRENT (fns);
1724 if (TREE_CODE (fn) == TEMPLATE_DECL)
1726 tree decl_arg_types;
1729 /* In case of explicit specialization, we need to check if
1730 the number of template headers appearing in the specialization
1731 is correct. This is usually done in check_explicit_specialization,
1732 but the check done there cannot be exhaustive when specializing
1733 member functions. Consider the following code:
1735 template <> void A<int>::f(int);
1736 template <> template <> void A<int>::f(int);
1738 Assuming that A<int> is not itself an explicit specialization
1739 already, the first line specializes "f" which is a non-template
1740 member function, whilst the second line specializes "f" which
1741 is a template member function. So both lines are syntactically
1742 correct, and check_explicit_specialization does not reject
1745 Here, we can do better, as we are matching the specialization
1746 against the declarations. We count the number of template
1747 headers, and we check if they match TEMPLATE_COUNT + 1
1748 (TEMPLATE_COUNT is the number of qualifying template classes,
1749 plus there must be another header for the member template
1752 Notice that if header_count is zero, this is not a
1753 specialization but rather a template instantiation, so there
1754 is no check we can perform here. */
1755 if (header_count && header_count != template_count + 1)
1758 /* Check that the number of template arguments at the
1759 innermost level for DECL is the same as for FN. */
1760 if (current_binding_level->kind == sk_template_parms
1761 && !current_binding_level->explicit_spec_p
1762 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1763 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1764 (current_template_parms))))
1767 /* DECL might be a specialization of FN. */
1768 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1769 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1771 /* For a non-static member function, we need to make sure
1772 that the const qualification is the same. Since
1773 get_bindings does not try to merge the "this" parameter,
1774 we must do the comparison explicitly. */
1775 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1776 && !same_type_p (TREE_VALUE (fn_arg_types),
1777 TREE_VALUE (decl_arg_types)))
1780 /* Skip the "this" parameter and, for constructors of
1781 classes with virtual bases, the VTT parameter. A
1782 full specialization of a constructor will have a VTT
1783 parameter, but a template never will. */
1785 = skip_artificial_parms_for (decl, decl_arg_types);
1787 = skip_artificial_parms_for (fn, fn_arg_types);
1789 /* Check that the number of function parameters matches.
1791 template <class T> void f(int i = 0);
1792 template <> void f<int>();
1793 The specialization f<int> is invalid but is not caught
1794 by get_bindings below. */
1795 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1798 /* Function templates cannot be specializations; there are
1799 no partial specializations of functions. Therefore, if
1800 the type of DECL does not match FN, there is no
1802 if (tsk == tsk_template)
1804 if (compparms (fn_arg_types, decl_arg_types))
1805 candidates = tree_cons (NULL_TREE, fn, candidates);
1809 /* See whether this function might be a specialization of this
1811 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1814 /* We cannot deduce template arguments that when used to
1815 specialize TMPL will produce DECL. */
1818 /* Save this template, and the arguments deduced. */
1819 templates = tree_cons (targs, fn, templates);
1821 else if (need_member_template)
1822 /* FN is an ordinary member function, and we need a
1823 specialization of a member template. */
1825 else if (TREE_CODE (fn) != FUNCTION_DECL)
1826 /* We can get IDENTIFIER_NODEs here in certain erroneous
1829 else if (!DECL_FUNCTION_MEMBER_P (fn))
1830 /* This is just an ordinary non-member function. Nothing can
1831 be a specialization of that. */
1833 else if (DECL_ARTIFICIAL (fn))
1834 /* Cannot specialize functions that are created implicitly. */
1838 tree decl_arg_types;
1840 /* This is an ordinary member function. However, since
1841 we're here, we can assume it's enclosing class is a
1842 template class. For example,
1844 template <typename T> struct S { void f(); };
1845 template <> void S<int>::f() {}
1847 Here, S<int>::f is a non-template, but S<int> is a
1848 template class. If FN has the same type as DECL, we
1849 might be in business. */
1851 if (!DECL_TEMPLATE_INFO (fn))
1852 /* Its enclosing class is an explicit specialization
1853 of a template class. This is not a candidate. */
1856 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1857 TREE_TYPE (TREE_TYPE (fn))))
1858 /* The return types differ. */
1861 /* Adjust the type of DECL in case FN is a static member. */
1862 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1863 if (DECL_STATIC_FUNCTION_P (fn)
1864 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1865 decl_arg_types = TREE_CHAIN (decl_arg_types);
1867 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1870 candidates = tree_cons (NULL_TREE, fn, candidates);
1874 if (templates && TREE_CHAIN (templates))
1880 It is possible for a specialization with a given function
1881 signature to be instantiated from more than one function
1882 template. In such cases, explicit specification of the
1883 template arguments must be used to uniquely identify the
1884 function template specialization being specialized.
1886 Note that here, there's no suggestion that we're supposed to
1887 determine which of the candidate templates is most
1888 specialized. However, we, also have:
1892 Partial ordering of overloaded function template
1893 declarations is used in the following contexts to select
1894 the function template to which a function template
1895 specialization refers:
1897 -- when an explicit specialization refers to a function
1900 So, we do use the partial ordering rules, at least for now.
1901 This extension can only serve to make invalid programs valid,
1902 so it's safe. And, there is strong anecdotal evidence that
1903 the committee intended the partial ordering rules to apply;
1904 the EDG front end has that behavior, and John Spicer claims
1905 that the committee simply forgot to delete the wording in
1906 [temp.expl.spec]. */
1907 tree tmpl = most_specialized_instantiation (templates);
1908 if (tmpl != error_mark_node)
1911 TREE_CHAIN (templates) = NULL_TREE;
1915 if (templates == NULL_TREE && candidates == NULL_TREE)
1917 error ("template-id %qD for %q+D does not match any template "
1918 "declaration", template_id, decl);
1919 return error_mark_node;
1921 else if ((templates && TREE_CHAIN (templates))
1922 || (candidates && TREE_CHAIN (candidates))
1923 || (templates && candidates))
1925 error ("ambiguous template specialization %qD for %q+D",
1927 chainon (candidates, templates);
1928 print_candidates (candidates);
1929 return error_mark_node;
1932 /* We have one, and exactly one, match. */
1935 tree fn = TREE_VALUE (candidates);
1936 *targs_out = copy_node (DECL_TI_ARGS (fn));
1937 /* DECL is a re-declaration or partial instantiation of a template
1939 if (TREE_CODE (fn) == TEMPLATE_DECL)
1941 /* It was a specialization of an ordinary member function in a
1943 return DECL_TI_TEMPLATE (fn);
1946 /* It was a specialization of a template. */
1947 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1948 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1950 *targs_out = copy_node (targs);
1951 SET_TMPL_ARGS_LEVEL (*targs_out,
1952 TMPL_ARGS_DEPTH (*targs_out),
1953 TREE_PURPOSE (templates));
1956 *targs_out = TREE_PURPOSE (templates);
1957 return TREE_VALUE (templates);
1960 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1961 but with the default argument values filled in from those in the
1965 copy_default_args_to_explicit_spec_1 (tree spec_types,
1968 tree new_spec_types;
1973 if (spec_types == void_list_node)
1974 return void_list_node;
1976 /* Substitute into the rest of the list. */
1978 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1979 TREE_CHAIN (tmpl_types));
1981 /* Add the default argument for this parameter. */
1982 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1983 TREE_VALUE (spec_types),
1987 /* DECL is an explicit specialization. Replicate default arguments
1988 from the template it specializes. (That way, code like:
1990 template <class T> void f(T = 3);
1991 template <> void f(double);
1994 works, as required.) An alternative approach would be to look up
1995 the correct default arguments at the call-site, but this approach
1996 is consistent with how implicit instantiations are handled. */
1999 copy_default_args_to_explicit_spec (tree decl)
2004 tree new_spec_types;
2008 tree object_type = NULL_TREE;
2009 tree in_charge = NULL_TREE;
2010 tree vtt = NULL_TREE;
2012 /* See if there's anything we need to do. */
2013 tmpl = DECL_TI_TEMPLATE (decl);
2014 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2015 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2016 if (TREE_PURPOSE (t))
2021 old_type = TREE_TYPE (decl);
2022 spec_types = TYPE_ARG_TYPES (old_type);
2024 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2026 /* Remove the this pointer, but remember the object's type for
2028 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2029 spec_types = TREE_CHAIN (spec_types);
2030 tmpl_types = TREE_CHAIN (tmpl_types);
2032 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2034 /* DECL may contain more parameters than TMPL due to the extra
2035 in-charge parameter in constructors and destructors. */
2036 in_charge = spec_types;
2037 spec_types = TREE_CHAIN (spec_types);
2039 if (DECL_HAS_VTT_PARM_P (decl))
2042 spec_types = TREE_CHAIN (spec_types);
2046 /* Compute the merged default arguments. */
2048 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2050 /* Compute the new FUNCTION_TYPE. */
2054 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2059 /* Put the in-charge parameter back. */
2060 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2061 TREE_VALUE (in_charge),
2064 new_type = build_method_type_directly (object_type,
2065 TREE_TYPE (old_type),
2069 new_type = build_function_type (TREE_TYPE (old_type),
2071 new_type = cp_build_type_attribute_variant (new_type,
2072 TYPE_ATTRIBUTES (old_type));
2073 new_type = build_exception_variant (new_type,
2074 TYPE_RAISES_EXCEPTIONS (old_type));
2075 TREE_TYPE (decl) = new_type;
2078 /* Check to see if the function just declared, as indicated in
2079 DECLARATOR, and in DECL, is a specialization of a function
2080 template. We may also discover that the declaration is an explicit
2081 instantiation at this point.
2083 Returns DECL, or an equivalent declaration that should be used
2084 instead if all goes well. Issues an error message if something is
2085 amiss. Returns error_mark_node if the error is not easily
2088 FLAGS is a bitmask consisting of the following flags:
2090 2: The function has a definition.
2091 4: The function is a friend.
2093 The TEMPLATE_COUNT is the number of references to qualifying
2094 template classes that appeared in the name of the function. For
2097 template <class T> struct S { void f(); };
2100 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2101 classes are not counted in the TEMPLATE_COUNT, so that in
2103 template <class T> struct S {};
2104 template <> struct S<int> { void f(); }
2105 template <> void S<int>::f();
2107 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2108 invalid; there should be no template <>.)
2110 If the function is a specialization, it is marked as such via
2111 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2112 is set up correctly, and it is added to the list of specializations
2113 for that template. */
2116 check_explicit_specialization (tree declarator,
2121 int have_def = flags & 2;
2122 int is_friend = flags & 4;
2123 int specialization = 0;
2124 int explicit_instantiation = 0;
2125 int member_specialization = 0;
2126 tree ctype = DECL_CLASS_CONTEXT (decl);
2127 tree dname = DECL_NAME (decl);
2132 if (!processing_specialization)
2135 tsk = tsk_excessive_parms;
2138 tsk = current_tmpl_spec_kind (template_count);
2143 if (processing_specialization)
2146 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2148 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2151 /* This could be something like:
2153 template <class T> void f(T);
2154 class S { friend void f<>(int); } */
2158 /* This case handles bogus declarations like template <>
2159 template <class T> void f<int>(); */
2161 error ("template-id %qD in declaration of primary template",
2168 case tsk_invalid_member_spec:
2169 /* The error has already been reported in
2170 check_specialization_scope. */
2171 return error_mark_node;
2173 case tsk_invalid_expl_inst:
2174 error ("template parameter list used in explicit instantiation");
2180 error ("definition provided for explicit instantiation");
2182 explicit_instantiation = 1;
2185 case tsk_excessive_parms:
2186 case tsk_insufficient_parms:
2187 if (tsk == tsk_excessive_parms)
2188 error ("too many template parameter lists in declaration of %qD",
2190 else if (template_header_count)
2191 error("too few template parameter lists in declaration of %qD", decl);
2193 error("explicit specialization of %qD must be introduced by "
2194 "%<template <>%>", decl);
2198 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2200 member_specialization = 1;
2206 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2208 /* This case handles bogus declarations like template <>
2209 template <class T> void f<int>(); */
2211 if (uses_template_parms (declarator))
2212 error ("function template partial specialization %qD "
2213 "is not allowed", declarator);
2215 error ("template-id %qD in declaration of primary template",
2220 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2221 /* This is a specialization of a member template, without
2222 specialization the containing class. Something like:
2224 template <class T> struct S {
2225 template <class U> void f (U);
2227 template <> template <class U> void S<int>::f(U) {}
2229 That's a specialization -- but of the entire template. */
2237 if (specialization || member_specialization)
2239 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2240 for (; t; t = TREE_CHAIN (t))
2241 if (TREE_PURPOSE (t))
2243 permerror (input_location,
2244 "default argument specified in explicit specialization");
2249 if (specialization || member_specialization || explicit_instantiation)
2251 tree tmpl = NULL_TREE;
2252 tree targs = NULL_TREE;
2254 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2255 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2259 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2264 /* If there is no class context, the explicit instantiation
2265 must be at namespace scope. */
2266 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2268 /* Find the namespace binding, using the declaration
2270 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2272 if (fns == error_mark_node || !is_overloaded_fn (fns))
2274 error ("%qD is not a template function", dname);
2275 fns = error_mark_node;
2279 tree fn = OVL_CURRENT (fns);
2280 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2281 CP_DECL_CONTEXT (fn)))
2282 error ("%qD is not declared in %qD",
2283 decl, current_namespace);
2287 declarator = lookup_template_function (fns, NULL_TREE);
2290 if (declarator == error_mark_node)
2291 return error_mark_node;
2293 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2295 if (!explicit_instantiation)
2296 /* A specialization in class scope. This is invalid,
2297 but the error will already have been flagged by
2298 check_specialization_scope. */
2299 return error_mark_node;
2302 /* It's not valid to write an explicit instantiation in
2305 class C { template void f(); }
2307 This case is caught by the parser. However, on
2310 template class C { void f(); };
2312 (which is invalid) we can get here. The error will be
2319 else if (ctype != NULL_TREE
2320 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2323 /* Find the list of functions in ctype that have the same
2324 name as the declared function. */
2325 tree name = TREE_OPERAND (declarator, 0);
2326 tree fns = NULL_TREE;
2329 if (constructor_name_p (name, ctype))
2331 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2333 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2334 : !CLASSTYPE_DESTRUCTORS (ctype))
2336 /* From [temp.expl.spec]:
2338 If such an explicit specialization for the member
2339 of a class template names an implicitly-declared
2340 special member function (clause _special_), the
2341 program is ill-formed.
2343 Similar language is found in [temp.explicit]. */
2344 error ("specialization of implicitly-declared special member function");
2345 return error_mark_node;
2348 name = is_constructor ? ctor_identifier : dtor_identifier;
2351 if (!DECL_CONV_FN_P (decl))
2353 idx = lookup_fnfields_1 (ctype, name);
2355 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2359 VEC(tree,gc) *methods;
2362 /* For a type-conversion operator, we cannot do a
2363 name-based lookup. We might be looking for `operator
2364 int' which will be a specialization of `operator T'.
2365 So, we find *all* the conversion operators, and then
2366 select from them. */
2369 methods = CLASSTYPE_METHOD_VEC (ctype);
2371 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2372 VEC_iterate (tree, methods, idx, ovl);
2375 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2376 /* There are no more conversion functions. */
2379 /* Glue all these conversion functions together
2380 with those we already have. */
2381 for (; ovl; ovl = OVL_NEXT (ovl))
2382 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2386 if (fns == NULL_TREE)
2388 error ("no member function %qD declared in %qT", name, ctype);
2389 return error_mark_node;
2392 TREE_OPERAND (declarator, 0) = fns;
2395 /* Figure out what exactly is being specialized at this point.
2396 Note that for an explicit instantiation, even one for a
2397 member function, we cannot tell apriori whether the
2398 instantiation is for a member template, or just a member
2399 function of a template class. Even if a member template is
2400 being instantiated, the member template arguments may be
2401 elided if they can be deduced from the rest of the
2403 tmpl = determine_specialization (declarator, decl,
2405 member_specialization,
2409 if (!tmpl || tmpl == error_mark_node)
2410 /* We couldn't figure out what this declaration was
2412 return error_mark_node;
2415 tree gen_tmpl = most_general_template (tmpl);
2417 if (explicit_instantiation)
2419 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2420 is done by do_decl_instantiation later. */
2422 int arg_depth = TMPL_ARGS_DEPTH (targs);
2423 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2425 if (arg_depth > parm_depth)
2427 /* If TMPL is not the most general template (for
2428 example, if TMPL is a friend template that is
2429 injected into namespace scope), then there will
2430 be too many levels of TARGS. Remove some of them
2435 new_targs = make_tree_vec (parm_depth);
2436 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2437 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2438 = TREE_VEC_ELT (targs, i);
2442 return instantiate_template (tmpl, targs, tf_error);
2445 /* If we thought that the DECL was a member function, but it
2446 turns out to be specializing a static member function,
2447 make DECL a static member function as well. */
2448 if (DECL_STATIC_FUNCTION_P (tmpl)
2449 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2450 revert_static_member_fn (decl);
2452 /* If this is a specialization of a member template of a
2453 template class, we want to return the TEMPLATE_DECL, not
2454 the specialization of it. */
2455 if (tsk == tsk_template)
2457 tree result = DECL_TEMPLATE_RESULT (tmpl);
2458 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2459 DECL_INITIAL (result) = NULL_TREE;
2463 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2464 DECL_SOURCE_LOCATION (result)
2465 = DECL_SOURCE_LOCATION (decl);
2466 /* We want to use the argument list specified in the
2467 definition, not in the original declaration. */
2468 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2469 for (parm = DECL_ARGUMENTS (result); parm;
2470 parm = TREE_CHAIN (parm))
2471 DECL_CONTEXT (parm) = result;
2473 return register_specialization (tmpl, gen_tmpl, targs,
2477 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2478 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2480 /* Inherit default function arguments from the template
2481 DECL is specializing. */
2482 copy_default_args_to_explicit_spec (decl);
2484 /* This specialization has the same protection as the
2485 template it specializes. */
2486 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2487 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2489 /* 7.1.1-1 [dcl.stc]
2491 A storage-class-specifier shall not be specified in an
2492 explicit specialization...
2494 The parser rejects these, so unless action is taken here,
2495 explicit function specializations will always appear with
2498 The action recommended by the C++ CWG in response to C++
2499 defect report 605 is to make the storage class and linkage
2500 of the explicit specialization match the templated function:
2502 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2504 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2506 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2507 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2509 /* This specialization has the same linkage and visibility as
2510 the function template it specializes. */
2511 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2512 if (! TREE_PUBLIC (decl))
2514 DECL_INTERFACE_KNOWN (decl) = 1;
2515 DECL_NOT_REALLY_EXTERN (decl) = 1;
2517 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2518 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2520 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2521 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2525 /* If DECL is a friend declaration, declared using an
2526 unqualified name, the namespace associated with DECL may
2527 have been set incorrectly. For example, in:
2529 template <typename T> void f(T);
2531 struct S { friend void f<int>(int); }
2534 we will have set the DECL_CONTEXT for the friend
2535 declaration to N, rather than to the global namespace. */
2536 if (DECL_NAMESPACE_SCOPE_P (decl))
2537 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2539 if (is_friend && !have_def)
2540 /* This is not really a declaration of a specialization.
2541 It's just the name of an instantiation. But, it's not
2542 a request for an instantiation, either. */
2543 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2544 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2545 /* This is indeed a specialization. In case of constructors
2546 and destructors, we need in-charge and not-in-charge
2547 versions in V3 ABI. */
2548 clone_function_decl (decl, /*update_method_vec_p=*/0);
2550 /* Register this specialization so that we can find it
2552 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2559 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2560 parameters. These are represented in the same format used for
2561 DECL_TEMPLATE_PARMS. */
2564 comp_template_parms (const_tree parms1, const_tree parms2)
2569 if (parms1 == parms2)
2572 for (p1 = parms1, p2 = parms2;
2573 p1 != NULL_TREE && p2 != NULL_TREE;
2574 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2576 tree t1 = TREE_VALUE (p1);
2577 tree t2 = TREE_VALUE (p2);
2580 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2581 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2583 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2586 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2588 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2589 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2591 /* If either of the template parameters are invalid, assume
2592 they match for the sake of error recovery. */
2593 if (parm1 == error_mark_node || parm2 == error_mark_node)
2596 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2599 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2600 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2601 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2603 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2608 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2609 /* One set of parameters has more parameters lists than the
2616 /* Determine whether PARM is a parameter pack. */
2618 template_parameter_pack_p (const_tree parm)
2620 /* Determine if we have a non-type template parameter pack. */
2621 if (TREE_CODE (parm) == PARM_DECL)
2622 return (DECL_TEMPLATE_PARM_P (parm)
2623 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2625 /* If this is a list of template parameters, we could get a
2626 TYPE_DECL or a TEMPLATE_DECL. */
2627 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2628 parm = TREE_TYPE (parm);
2630 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2631 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2632 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2635 /* Determine whether ARGS describes a variadic template args list,
2636 i.e., one that is terminated by a template argument pack. */
2638 template_args_variadic_p (tree args)
2643 if (args == NULL_TREE)
2646 args = INNERMOST_TEMPLATE_ARGS (args);
2647 nargs = TREE_VEC_LENGTH (args);
2652 last_parm = TREE_VEC_ELT (args, nargs - 1);
2654 return ARGUMENT_PACK_P (last_parm);
2657 /* Generate a new name for the parameter pack name NAME (an
2658 IDENTIFIER_NODE) that incorporates its */
2660 make_ith_pack_parameter_name (tree name, int i)
2662 /* Munge the name to include the parameter index. */
2666 sprintf(numbuf, "%i", i);
2667 newname = (char*)alloca (IDENTIFIER_LENGTH (name) + strlen(numbuf) + 2);
2668 sprintf(newname, "%s#%i", IDENTIFIER_POINTER (name), i);
2669 return get_identifier (newname);
2672 /* Structure used to track the progress of find_parameter_packs_r. */
2673 struct find_parameter_pack_data
2675 /* TREE_LIST that will contain all of the parameter packs found by
2677 tree* parameter_packs;
2679 /* Set of AST nodes that have been visited by the traversal. */
2680 struct pointer_set_t *visited;
2683 /* Identifies all of the argument packs that occur in a template
2684 argument and appends them to the TREE_LIST inside DATA, which is a
2685 find_parameter_pack_data structure. This is a subroutine of
2686 make_pack_expansion and uses_parameter_packs. */
2688 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2691 struct find_parameter_pack_data* ppd =
2692 (struct find_parameter_pack_data*)data;
2693 bool parameter_pack_p = false;
2695 /* Identify whether this is a parameter pack or not. */
2696 switch (TREE_CODE (t))
2698 case TEMPLATE_PARM_INDEX:
2699 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2700 parameter_pack_p = true;
2703 case TEMPLATE_TYPE_PARM:
2704 case TEMPLATE_TEMPLATE_PARM:
2705 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2706 parameter_pack_p = true;
2710 if (FUNCTION_PARAMETER_PACK_P (t))
2712 /* We don't want to walk into the type of a PARM_DECL,
2713 because we don't want to see the type parameter pack. */
2715 parameter_pack_p = true;
2720 /* Not a parameter pack. */
2724 if (parameter_pack_p)
2726 /* Add this parameter pack to the list. */
2727 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2731 cp_walk_tree (&TYPE_CONTEXT (t),
2732 &find_parameter_packs_r, ppd, ppd->visited);
2734 /* This switch statement will return immediately if we don't find a
2736 switch (TREE_CODE (t))
2738 case TEMPLATE_PARM_INDEX:
2741 case BOUND_TEMPLATE_TEMPLATE_PARM:
2742 /* Check the template itself. */
2743 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2744 &find_parameter_packs_r, ppd, ppd->visited);
2745 /* Check the template arguments. */
2746 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2751 case TEMPLATE_TYPE_PARM:
2752 case TEMPLATE_TEMPLATE_PARM:
2759 if (TYPE_PTRMEMFUNC_P (t))
2765 if (TYPE_TEMPLATE_INFO (t))
2766 cp_walk_tree (&TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
2767 &find_parameter_packs_r, ppd, ppd->visited);
2773 cp_walk_tree (&TREE_TYPE (t),
2774 &find_parameter_packs_r, ppd, ppd->visited);
2778 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
2783 case TYPE_PACK_EXPANSION:
2784 case EXPR_PACK_EXPANSION:
2789 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
2794 case IDENTIFIER_NODE:
2795 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
2807 /* Determines if the expression or type T uses any parameter packs. */
2809 uses_parameter_packs (tree t)
2811 tree parameter_packs = NULL_TREE;
2812 struct find_parameter_pack_data ppd;
2813 ppd.parameter_packs = ¶meter_packs;
2814 ppd.visited = pointer_set_create ();
2815 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2816 pointer_set_destroy (ppd.visited);
2817 return parameter_packs != NULL_TREE;
2820 /* Turn ARG, which may be an expression, type, or a TREE_LIST
2821 representation a base-class initializer into a parameter pack
2822 expansion. If all goes well, the resulting node will be an
2823 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
2826 make_pack_expansion (tree arg)
2829 tree parameter_packs = NULL_TREE;
2830 bool for_types = false;
2831 struct find_parameter_pack_data ppd;
2833 if (!arg || arg == error_mark_node)
2836 if (TREE_CODE (arg) == TREE_LIST)
2838 /* The only time we will see a TREE_LIST here is for a base
2839 class initializer. In this case, the TREE_PURPOSE will be a
2840 _TYPE node (representing the base class expansion we're
2841 initializing) and the TREE_VALUE will be a TREE_LIST
2842 containing the initialization arguments.
2844 The resulting expansion looks somewhat different from most
2845 expansions. Rather than returning just one _EXPANSION, we
2846 return a TREE_LIST whose TREE_PURPOSE is a
2847 TYPE_PACK_EXPANSION containing the bases that will be
2848 initialized. The TREE_VALUE will be identical to the
2849 original TREE_VALUE, which is a list of arguments that will
2850 be passed to each base. We do not introduce any new pack
2851 expansion nodes into the TREE_VALUE (although it is possible
2852 that some already exist), because the TREE_PURPOSE and
2853 TREE_VALUE all need to be expanded together with the same
2854 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
2855 resulting TREE_PURPOSE will mention the parameter packs in
2856 both the bases and the arguments to the bases. */
2859 tree parameter_packs = NULL_TREE;
2861 /* Determine which parameter packs will be used by the base
2863 ppd.visited = pointer_set_create ();
2864 ppd.parameter_packs = ¶meter_packs;
2865 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
2868 if (parameter_packs == NULL_TREE)
2870 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
2871 pointer_set_destroy (ppd.visited);
2872 return error_mark_node;
2875 if (TREE_VALUE (arg) != void_type_node)
2877 /* Collect the sets of parameter packs used in each of the
2878 initialization arguments. */
2879 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
2881 /* Determine which parameter packs will be expanded in this
2883 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
2888 pointer_set_destroy (ppd.visited);
2890 /* Create the pack expansion type for the base type. */
2891 purpose = make_node (TYPE_PACK_EXPANSION);
2892 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
2893 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
2895 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2896 they will rarely be compared to anything. */
2897 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
2899 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
2902 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
2905 /* Build the PACK_EXPANSION_* node. */
2906 result = make_node (for_types ? TYPE_PACK_EXPANSION : EXPR_PACK_EXPANSION);
2907 SET_PACK_EXPANSION_PATTERN (result, arg);
2908 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
2910 /* Propagate type and const-expression information. */
2911 TREE_TYPE (result) = TREE_TYPE (arg);
2912 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
2915 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2916 they will rarely be compared to anything. */
2917 SET_TYPE_STRUCTURAL_EQUALITY (result);
2919 /* Determine which parameter packs will be expanded. */
2920 ppd.parameter_packs = ¶meter_packs;
2921 ppd.visited = pointer_set_create ();
2922 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
2923 pointer_set_destroy (ppd.visited);
2925 /* Make sure we found some parameter packs. */
2926 if (parameter_packs == NULL_TREE)
2929 error ("expansion pattern %<%T%> contains no argument packs", arg);
2931 error ("expansion pattern %<%E%> contains no argument packs", arg);
2932 return error_mark_node;
2934 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
2939 /* Checks T for any "bare" parameter packs, which have not yet been
2940 expanded, and issues an error if any are found. This operation can
2941 only be done on full expressions or types (e.g., an expression
2942 statement, "if" condition, etc.), because we could have expressions like:
2944 foo(f(g(h(args)))...)
2946 where "args" is a parameter pack. check_for_bare_parameter_packs
2947 should not be called for the subexpressions args, h(args),
2948 g(h(args)), or f(g(h(args))), because we would produce erroneous
2951 Returns TRUE and emits an error if there were bare parameter packs,
2952 returns FALSE otherwise. */
2954 check_for_bare_parameter_packs (tree t)
2956 tree parameter_packs = NULL_TREE;
2957 struct find_parameter_pack_data ppd;
2959 if (!processing_template_decl || !t || t == error_mark_node)
2962 if (TREE_CODE (t) == TYPE_DECL)
2965 ppd.parameter_packs = ¶meter_packs;
2966 ppd.visited = pointer_set_create ();
2967 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2968 pointer_set_destroy (ppd.visited);
2970 if (parameter_packs)
2972 error ("parameter packs not expanded with %<...%>:");
2973 while (parameter_packs)
2975 tree pack = TREE_VALUE (parameter_packs);
2976 tree name = NULL_TREE;
2978 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
2979 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
2980 name = TYPE_NAME (pack);
2981 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
2982 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
2984 name = DECL_NAME (pack);
2987 inform (input_location, " %qD", name);
2989 inform (input_location, " <anonymous>");
2991 parameter_packs = TREE_CHAIN (parameter_packs);
3000 /* Expand any parameter packs that occur in the template arguments in
3003 expand_template_argument_pack (tree args)
3005 tree result_args = NULL_TREE;
3006 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3007 int num_result_args = -1;
3009 /* First, determine if we need to expand anything, and the number of
3010 slots we'll need. */
3011 for (in_arg = 0; in_arg < nargs; ++in_arg)
3013 tree arg = TREE_VEC_ELT (args, in_arg);
3014 if (ARGUMENT_PACK_P (arg))
3016 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3017 if (num_result_args < 0)
3018 num_result_args = in_arg + num_packed;
3020 num_result_args += num_packed;
3024 if (num_result_args >= 0)
3029 /* If no expansion is necessary, we're done. */
3030 if (num_result_args < 0)
3033 /* Expand arguments. */
3034 result_args = make_tree_vec (num_result_args);
3035 for (in_arg = 0; in_arg < nargs; ++in_arg)
3037 tree arg = TREE_VEC_ELT (args, in_arg);
3038 if (ARGUMENT_PACK_P (arg))
3040 tree packed = ARGUMENT_PACK_ARGS (arg);
3041 int i, num_packed = TREE_VEC_LENGTH (packed);
3042 for (i = 0; i < num_packed; ++i, ++out_arg)
3043 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3047 TREE_VEC_ELT (result_args, out_arg) = arg;
3055 /* Checks if DECL shadows a template parameter.
3057 [temp.local]: A template-parameter shall not be redeclared within its
3058 scope (including nested scopes).
3060 Emits an error and returns TRUE if the DECL shadows a parameter,
3061 returns FALSE otherwise. */
3064 check_template_shadow (tree decl)
3068 /* If we're not in a template, we can't possibly shadow a template
3070 if (!current_template_parms)
3073 /* Figure out what we're shadowing. */
3074 if (TREE_CODE (decl) == OVERLOAD)
3075 decl = OVL_CURRENT (decl);
3076 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3078 /* If there's no previous binding for this name, we're not shadowing
3079 anything, let alone a template parameter. */
3083 /* If we're not shadowing a template parameter, we're done. Note
3084 that OLDDECL might be an OVERLOAD (or perhaps even an
3085 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3087 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3090 /* We check for decl != olddecl to avoid bogus errors for using a
3091 name inside a class. We check TPFI to avoid duplicate errors for
3092 inline member templates. */
3094 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3097 error ("declaration of %q+#D", decl);
3098 error (" shadows template parm %q+#D", olddecl);
3102 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3103 ORIG_LEVEL, DECL, and TYPE. */
3106 build_template_parm_index (int index,
3112 tree t = make_node (TEMPLATE_PARM_INDEX);
3113 TEMPLATE_PARM_IDX (t) = index;
3114 TEMPLATE_PARM_LEVEL (t) = level;
3115 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3116 TEMPLATE_PARM_DECL (t) = decl;
3117 TREE_TYPE (t) = type;
3118 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3119 TREE_READONLY (t) = TREE_READONLY (decl);
3124 /* Find the canonical type parameter for the given template type
3125 parameter. Returns the canonical type parameter, which may be TYPE
3126 if no such parameter existed. */
3128 canonical_type_parameter (tree type)
3131 int idx = TEMPLATE_TYPE_IDX (type);
3132 if (!canonical_template_parms)
3133 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3135 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3136 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3138 list = VEC_index (tree, canonical_template_parms, idx);
3139 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3140 list = TREE_CHAIN (list);
3143 return TREE_VALUE (list);
3146 VEC_replace(tree, canonical_template_parms, idx,
3147 tree_cons (NULL_TREE, type,
3148 VEC_index (tree, canonical_template_parms, idx)));
3153 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3154 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3155 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3156 new one is created. */
3159 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3160 tsubst_flags_t complain)
3162 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3163 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3164 != TEMPLATE_PARM_LEVEL (index) - levels))
3166 tree orig_decl = TEMPLATE_PARM_DECL (index);
3169 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3170 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3171 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3172 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3173 DECL_ARTIFICIAL (decl) = 1;
3174 SET_DECL_TEMPLATE_PARM_P (decl);
3176 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3177 TEMPLATE_PARM_LEVEL (index) - levels,
3178 TEMPLATE_PARM_ORIG_LEVEL (index),
3180 TEMPLATE_PARM_DESCENDANTS (index) = t;
3181 TEMPLATE_PARM_PARAMETER_PACK (t)
3182 = TEMPLATE_PARM_PARAMETER_PACK (index);
3184 /* Template template parameters need this. */
3185 if (TREE_CODE (decl) == TEMPLATE_DECL)
3186 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3187 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3191 return TEMPLATE_PARM_DESCENDANTS (index);
3194 /* Process information from new template parameter PARM and append it to the
3195 LIST being built. This new parameter is a non-type parameter iff
3196 IS_NON_TYPE is true. This new parameter is a parameter
3197 pack iff IS_PARAMETER_PACK is true. The location of PARM is in
3201 process_template_parm (tree list, location_t parm_loc, tree parm, bool is_non_type,
3202 bool is_parameter_pack)
3209 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3210 defval = TREE_PURPOSE (parm);
3214 tree p = tree_last (list);
3216 if (p && TREE_VALUE (p) != error_mark_node)
3219 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3220 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3222 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3232 parm = TREE_VALUE (parm);
3234 SET_DECL_TEMPLATE_PARM_P (parm);
3236 if (TREE_TYPE (parm) == error_mark_node)
3238 err_parm_list = build_tree_list (defval, parm);
3239 TREE_VALUE (err_parm_list) = error_mark_node;
3240 return chainon (list, err_parm_list);
3246 The top-level cv-qualifiers on the template-parameter are
3247 ignored when determining its type. */
3248 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3249 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3251 err_parm_list = build_tree_list (defval, parm);
3252 TREE_VALUE (err_parm_list) = error_mark_node;
3253 return chainon (list, err_parm_list);
3256 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3258 /* This template parameter is not a parameter pack, but it
3259 should be. Complain about "bare" parameter packs. */
3260 check_for_bare_parameter_packs (TREE_TYPE (parm));
3262 /* Recover by calling this a parameter pack. */
3263 is_parameter_pack = true;
3267 /* A template parameter is not modifiable. */
3268 TREE_CONSTANT (parm) = 1;
3269 TREE_READONLY (parm) = 1;
3270 decl = build_decl (parm_loc,
3271 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3272 TREE_CONSTANT (decl) = 1;
3273 TREE_READONLY (decl) = 1;
3274 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3275 = build_template_parm_index (idx, processing_template_decl,
3276 processing_template_decl,
3277 decl, TREE_TYPE (parm));
3279 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3280 = is_parameter_pack;
3285 parm = TREE_VALUE (TREE_VALUE (parm));
3287 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3289 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3290 /* This is for distinguishing between real templates and template
3291 template parameters */
3292 TREE_TYPE (parm) = t;
3293 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3298 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3299 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3300 decl = build_decl (parm_loc,
3301 TYPE_DECL, parm, t);
3304 TYPE_NAME (t) = decl;
3305 TYPE_STUB_DECL (t) = decl;
3307 TEMPLATE_TYPE_PARM_INDEX (t)
3308 = build_template_parm_index (idx, processing_template_decl,
3309 processing_template_decl,
3310 decl, TREE_TYPE (parm));
3311 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3312 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3314 DECL_ARTIFICIAL (decl) = 1;
3315 SET_DECL_TEMPLATE_PARM_P (decl);
3317 parm = build_tree_list (defval, parm);
3318 return chainon (list, parm);
3321 /* The end of a template parameter list has been reached. Process the
3322 tree list into a parameter vector, converting each parameter into a more
3323 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3327 end_template_parm_list (tree parms)
3331 tree saved_parmlist = make_tree_vec (list_length (parms));
3333 current_template_parms
3334 = tree_cons (size_int (processing_template_decl),
3335 saved_parmlist, current_template_parms);
3337 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3339 next = TREE_CHAIN (parm);
3340 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3341 TREE_CHAIN (parm) = NULL_TREE;
3344 --processing_template_parmlist;
3346 return saved_parmlist;
3349 /* end_template_decl is called after a template declaration is seen. */
3352 end_template_decl (void)
3354 reset_specialization ();
3356 if (! processing_template_decl)
3359 /* This matches the pushlevel in begin_template_parm_list. */
3362 --processing_template_decl;
3363 current_template_parms = TREE_CHAIN (current_template_parms);
3366 /* Within the declaration of a template, return all levels of template
3367 parameters that apply. The template parameters are represented as
3368 a TREE_VEC, in the form documented in cp-tree.h for template
3372 current_template_args (void)
3375 tree args = NULL_TREE;
3376 int length = TMPL_PARMS_DEPTH (current_template_parms);
3379 /* If there is only one level of template parameters, we do not
3380 create a TREE_VEC of TREE_VECs. Instead, we return a single
3381 TREE_VEC containing the arguments. */
3383 args = make_tree_vec (length);
3385 for (header = current_template_parms; header; header = TREE_CHAIN (header))
3387 tree a = copy_node (TREE_VALUE (header));
3390 TREE_TYPE (a) = NULL_TREE;
3391 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3393 tree t = TREE_VEC_ELT (a, i);
3395 /* T will be a list if we are called from within a
3396 begin/end_template_parm_list pair, but a vector directly
3397 if within a begin/end_member_template_processing pair. */
3398 if (TREE_CODE (t) == TREE_LIST)
3402 if (!error_operand_p (t))
3404 if (TREE_CODE (t) == TYPE_DECL
3405 || TREE_CODE (t) == TEMPLATE_DECL)
3409 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3411 /* Turn this argument into a TYPE_ARGUMENT_PACK
3412 with a single element, which expands T. */
3413 tree vec = make_tree_vec (1);
3414 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3416 t = make_node (TYPE_ARGUMENT_PACK);
3417 SET_ARGUMENT_PACK_ARGS (t, vec);
3422 t = DECL_INITIAL (t);
3424 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3426 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3427 with a single element, which expands T. */
3428 tree vec = make_tree_vec (1);
3429 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3430 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3432 t = make_node (NONTYPE_ARGUMENT_PACK);
3433 SET_ARGUMENT_PACK_ARGS (t, vec);
3434 TREE_TYPE (t) = type;
3437 TREE_VEC_ELT (a, i) = t;
3443 TREE_VEC_ELT (args, --l) = a;
3451 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3452 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3453 a member template. Used by push_template_decl below. */
3456 build_template_decl (tree decl, tree parms, bool member_template_p)
3458 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3459 DECL_TEMPLATE_PARMS (tmpl) = parms;
3460 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3461 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3466 struct template_parm_data
3468 /* The level of the template parameters we are currently
3472 /* The index of the specialization argument we are currently
3476 /* An array whose size is the number of template parameters. The
3477 elements are nonzero if the parameter has been used in any one
3478 of the arguments processed so far. */
3481 /* An array whose size is the number of template arguments. The
3482 elements are nonzero if the argument makes use of template
3483 parameters of this level. */
3484 int* arg_uses_template_parms;
3487 /* Subroutine of push_template_decl used to see if each template
3488 parameter in a partial specialization is used in the explicit
3489 argument list. If T is of the LEVEL given in DATA (which is
3490 treated as a template_parm_data*), then DATA->PARMS is marked
3494 mark_template_parm (tree t, void* data)
3498 struct template_parm_data* tpd = (struct template_parm_data*) data;
3500 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3502 level = TEMPLATE_PARM_LEVEL (t);
3503 idx = TEMPLATE_PARM_IDX (t);
3507 level = TEMPLATE_TYPE_LEVEL (t);
3508 idx = TEMPLATE_TYPE_IDX (t);
3511 if (level == tpd->level)
3513 tpd->parms[idx] = 1;
3514 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
3517 /* Return zero so that for_each_template_parm will continue the
3518 traversal of the tree; we want to mark *every* template parm. */
3522 /* Process the partial specialization DECL. */
3525 process_partial_specialization (tree decl)
3527 tree type = TREE_TYPE (decl);
3528 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
3529 tree specargs = CLASSTYPE_TI_ARGS (type);
3530 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
3531 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
3533 int nargs = TREE_VEC_LENGTH (inner_args);
3536 int did_error_intro = 0;
3537 struct template_parm_data tpd;
3538 struct template_parm_data tpd2;
3540 gcc_assert (current_template_parms);
3542 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3543 ntparms = TREE_VEC_LENGTH (inner_parms);
3545 /* We check that each of the template parameters given in the
3546 partial specialization is used in the argument list to the
3547 specialization. For example:
3549 template <class T> struct S;
3550 template <class T> struct S<T*>;
3552 The second declaration is OK because `T*' uses the template
3553 parameter T, whereas
3555 template <class T> struct S<int>;
3557 is no good. Even trickier is:
3568 The S2<T> declaration is actually invalid; it is a
3569 full-specialization. Of course,
3572 struct S2<T (*)(U)>;
3574 or some such would have been OK. */
3575 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
3576 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
3577 memset (tpd.parms, 0, sizeof (int) * ntparms);
3579 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
3580 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
3581 for (i = 0; i < nargs; ++i)
3583 tpd.current_arg = i;
3584 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
3585 &mark_template_parm,
3588 /*include_nondeduced_p=*/false);
3590 for (i = 0; i < ntparms; ++i)
3591 if (tpd.parms[i] == 0)
3593 /* One of the template parms was not used in the
3595 if (!did_error_intro)
3597 error ("template parameters not used in partial specialization:");
3598 did_error_intro = 1;
3601 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
3604 /* [temp.class.spec]
3606 The argument list of the specialization shall not be identical to
3607 the implicit argument list of the primary template. */
3608 if (comp_template_args
3610 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
3612 error ("partial specialization %qT does not specialize any template arguments", type);
3614 /* [temp.class.spec]
3616 A partially specialized non-type argument expression shall not
3617 involve template parameters of the partial specialization except
3618 when the argument expression is a simple identifier.
3620 The type of a template parameter corresponding to a specialized
3621 non-type argument shall not be dependent on a parameter of the
3624 Also, we verify that pack expansions only occur at the
3625 end of the argument list. */
3626 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
3628 for (i = 0; i < nargs; ++i)
3630 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
3631 tree arg = TREE_VEC_ELT (inner_args, i);
3632 tree packed_args = NULL_TREE;
3635 if (ARGUMENT_PACK_P (arg))
3637 /* Extract the arguments from the argument pack. We'll be
3638 iterating over these in the following loop. */
3639 packed_args = ARGUMENT_PACK_ARGS (arg);
3640 len = TREE_VEC_LENGTH (packed_args);
3643 for (j = 0; j < len; j++)
3646 /* Get the Jth argument in the parameter pack. */
3647 arg = TREE_VEC_ELT (packed_args, j);
3649 if (PACK_EXPANSION_P (arg))
3651 /* Pack expansions must come at the end of the
3653 if ((packed_args && j < len - 1)
3654 || (!packed_args && i < nargs - 1))
3656 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3657 error ("parameter pack argument %qE must be at the end of the template argument list", arg);
3659 error ("parameter pack argument %qT must be at the end of the template argument list", arg);
3662 TREE_VEC_ELT (packed_args, j) = error_mark_node;
3666 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3667 /* We only care about the pattern. */
3668 arg = PACK_EXPANSION_PATTERN (arg);
3670 if (/* These first two lines are the `non-type' bit. */
3672 && TREE_CODE (arg) != TEMPLATE_DECL
3673 /* This next line is the `argument expression is not just a
3674 simple identifier' condition and also the `specialized
3675 non-type argument' bit. */
3676 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
3678 if ((!packed_args && tpd.arg_uses_template_parms[i])
3679 || (packed_args && uses_template_parms (arg)))
3680 error ("template argument %qE involves template parameter(s)",
3684 /* Look at the corresponding template parameter,
3685 marking which template parameters its type depends
3687 tree type = TREE_TYPE (parm);
3691 /* We haven't yet initialized TPD2. Do so now. */
3692 tpd2.arg_uses_template_parms
3693 = (int *) alloca (sizeof (int) * nargs);
3694 /* The number of parameters here is the number in the
3695 main template, which, as checked in the assertion
3697 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
3699 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
3702 /* Mark the template parameters. But this time, we're
3703 looking for the template parameters of the main
3704 template, not in the specialization. */
3705 tpd2.current_arg = i;
3706 tpd2.arg_uses_template_parms[i] = 0;
3707 memset (tpd2.parms, 0, sizeof (int) * nargs);
3708 for_each_template_parm (type,
3709 &mark_template_parm,
3712 /*include_nondeduced_p=*/false);
3714 if (tpd2.arg_uses_template_parms [i])
3716 /* The type depended on some template parameters.
3717 If they are fully specialized in the
3718 specialization, that's OK. */
3720 for (j = 0; j < nargs; ++j)
3721 if (tpd2.parms[j] != 0
3722 && tpd.arg_uses_template_parms [j])
3724 error ("type %qT of template argument %qE depends "
3725 "on template parameter(s)",
3736 /* We should only get here once. */
3737 gcc_assert (!COMPLETE_TYPE_P (type));
3739 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
3740 = tree_cons (specargs, inner_parms,
3741 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
3742 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
3746 /* Check that a template declaration's use of default arguments and
3747 parameter packs is not invalid. Here, PARMS are the template
3748 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
3749 a primary template. IS_PARTIAL is nonzero if DECL is a partial
3753 IS_FRIEND_DECL is nonzero if DECL is a friend function template
3754 declaration (but not a definition); 1 indicates a declaration, 2
3755 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
3756 emitted for extraneous default arguments.
3758 Returns TRUE if there were no errors found, FALSE otherwise. */
3761 check_default_tmpl_args (tree decl, tree parms, int is_primary,
3762 int is_partial, int is_friend_decl)
3765 int last_level_to_check;
3767 bool no_errors = true;
3771 A default template-argument shall not be specified in a
3772 function template declaration or a function template definition, nor
3773 in the template-parameter-list of the definition of a member of a
3776 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
3777 /* You can't have a function template declaration in a local
3778 scope, nor you can you define a member of a class template in a
3782 if (current_class_type
3783 && !TYPE_BEING_DEFINED (current_class_type)
3784 && DECL_LANG_SPECIFIC (decl)
3785 && DECL_DECLARES_FUNCTION_P (decl)
3786 /* If this is either a friend defined in the scope of the class
3787 or a member function. */
3788 && (DECL_FUNCTION_MEMBER_P (decl)
3789 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
3790 : DECL_FRIEND_CONTEXT (decl)
3791 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
3793 /* And, if it was a member function, it really was defined in
3794 the scope of the class. */
3795 && (!DECL_FUNCTION_MEMBER_P (decl)
3796 || DECL_INITIALIZED_IN_CLASS_P (decl)))
3797 /* We already checked these parameters when the template was
3798 declared, so there's no need to do it again now. This function
3799 was defined in class scope, but we're processing it's body now
3800 that the class is complete. */
3803 /* Core issue 226 (C++0x only): the following only applies to class
3805 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
3809 If a template-parameter has a default template-argument, all
3810 subsequent template-parameters shall have a default
3811 template-argument supplied. */
3812 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
3814 tree inner_parms = TREE_VALUE (parm_level);
3815 int ntparms = TREE_VEC_LENGTH (inner_parms);
3816 int seen_def_arg_p = 0;
3819 for (i = 0; i < ntparms; ++i)
3821 tree parm = TREE_VEC_ELT (inner_parms, i);
3823 if (parm == error_mark_node)
3826 if (TREE_PURPOSE (parm))
3828 else if (seen_def_arg_p
3829 && !template_parameter_pack_p (TREE_VALUE (parm)))
3831 error ("no default argument for %qD", TREE_VALUE (parm));
3832 /* For better subsequent error-recovery, we indicate that
3833 there should have been a default argument. */
3834 TREE_PURPOSE (parm) = error_mark_node;
3840 /* Don't complain about an enclosing partial
3842 && parm_level == parms
3843 && TREE_CODE (decl) == TYPE_DECL
3845 && template_parameter_pack_p (TREE_VALUE (parm)))
3847 /* A primary class template can only have one
3848 parameter pack, at the end of the template
3851 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
3852 error ("parameter pack %qE must be at the end of the"
3853 " template parameter list", TREE_VALUE (parm));
3855 error ("parameter pack %qT must be at the end of the"
3856 " template parameter list",
3857 TREE_TYPE (TREE_VALUE (parm)));
3859 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
3867 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
3871 /* For an ordinary class template, default template arguments are
3872 allowed at the innermost level, e.g.:
3873 template <class T = int>
3875 but, in a partial specialization, they're not allowed even
3876 there, as we have in [temp.class.spec]:
3878 The template parameter list of a specialization shall not
3879 contain default template argument values.
3881 So, for a partial specialization, or for a function template
3882 (in C++98/C++03), we look at all of them. */
3885 /* But, for a primary class template that is not a partial
3886 specialization we look at all template parameters except the
3888 parms = TREE_CHAIN (parms);
3890 /* Figure out what error message to issue. */
3891 if (is_friend_decl == 2)
3892 msg = "default template arguments may not be used in function template friend re-declaration";
3893 else if (is_friend_decl)
3894 msg = "default template arguments may not be used in function template friend declarations";
3895 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
3896 msg = "default template arguments may not be used in function templates";
3897 else if (is_partial)
3898 msg = "default template arguments may not be used in partial specializations";
3900 msg = "default argument for template parameter for class enclosing %qD";
3902 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
3903 /* If we're inside a class definition, there's no need to
3904 examine the parameters to the class itself. On the one
3905 hand, they will be checked when the class is defined, and,
3906 on the other, default arguments are valid in things like:
3907 template <class T = double>
3908 struct S { template <class U> void f(U); };
3909 Here the default argument for `S' has no bearing on the
3910 declaration of `f'. */
3911 last_level_to_check = template_class_depth (current_class_type) + 1;
3913 /* Check everything. */
3914 last_level_to_check = 0;
3916 for (parm_level = parms;
3917 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
3918 parm_level = TREE_CHAIN (parm_level))
3920 tree inner_parms = TREE_VALUE (parm_level);
3924 ntparms = TREE_VEC_LENGTH (inner_parms);
3925 for (i = 0; i < ntparms; ++i)
3927 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
3930 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
3935 if (is_friend_decl == 2)
3942 /* Clear out the default argument so that we are not
3944 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
3948 /* At this point, if we're still interested in issuing messages,
3949 they must apply to classes surrounding the object declared. */
3951 msg = "default argument for template parameter for class enclosing %qD";
3957 /* Worker for push_template_decl_real, called via
3958 for_each_template_parm. DATA is really an int, indicating the
3959 level of the parameters we are interested in. If T is a template
3960 parameter of that level, return nonzero. */
3963 template_parm_this_level_p (tree t, void* data)
3965 int this_level = *(int *)data;
3968 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3969 level = TEMPLATE_PARM_LEVEL (t);
3971 level = TEMPLATE_TYPE_LEVEL (t);
3972 return level == this_level;
3975 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
3976 parameters given by current_template_args, or reuses a
3977 previously existing one, if appropriate. Returns the DECL, or an
3978 equivalent one, if it is replaced via a call to duplicate_decls.
3980 If IS_FRIEND is true, DECL is a friend declaration. */
3983 push_template_decl_real (tree decl, bool is_friend)
3991 int new_template_p = 0;
3992 /* True if the template is a member template, in the sense of
3994 bool member_template_p = false;
3996 if (decl == error_mark_node || !current_template_parms)
3997 return error_mark_node;
3999 /* See if this is a partial specialization. */
4000 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
4001 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
4002 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4004 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4008 /* For a friend, we want the context of the friend function, not
4009 the type of which it is a friend. */
4010 ctx = DECL_CONTEXT (decl);
4011 else if (CP_DECL_CONTEXT (decl)
4012 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4013 /* In the case of a virtual function, we want the class in which
4015 ctx = CP_DECL_CONTEXT (decl);
4017 /* Otherwise, if we're currently defining some class, the DECL
4018 is assumed to be a member of the class. */
4019 ctx = current_scope ();
4021 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4024 if (!DECL_CONTEXT (decl))
4025 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4027 /* See if this is a primary template. */
4028 if (is_friend && ctx)
4029 /* A friend template that specifies a class context, i.e.
4030 template <typename T> friend void A<T>::f();
4034 primary = template_parm_scope_p ();
4038 if (DECL_CLASS_SCOPE_P (decl))
4039 member_template_p = true;
4040 if (TREE_CODE (decl) == TYPE_DECL
4041 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4043 error ("template class without a name");
4044 return error_mark_node;
4046 else if (TREE_CODE (decl) == FUNCTION_DECL)
4048 if (DECL_DESTRUCTOR_P (decl))
4052 A destructor shall not be a member template. */
4053 error ("destructor %qD declared as member template", decl);
4054 return error_mark_node;
4056 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4057 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
4058 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4059 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4060 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4061 == void_list_node)))
4063 /* [basic.stc.dynamic.allocation]
4065 An allocation function can be a function
4066 template. ... Template allocation functions shall
4067 have two or more parameters. */
4068 error ("invalid template declaration of %qD", decl);
4069 return error_mark_node;
4072 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4073 && CLASS_TYPE_P (TREE_TYPE (decl)))
4077 error ("template declaration of %q#D", decl);
4078 return error_mark_node;
4082 /* Check to see that the rules regarding the use of default
4083 arguments are not being violated. */
4084 check_default_tmpl_args (decl, current_template_parms,
4085 primary, is_partial, /*is_friend_decl=*/0);
4087 /* Ensure that there are no parameter packs in the type of this
4088 declaration that have not been expanded. */
4089 if (TREE_CODE (decl) == FUNCTION_DECL)
4091 /* Check each of the arguments individually to see if there are
4092 any bare parameter packs. */
4093 tree type = TREE_TYPE (decl);
4094 tree arg = DECL_ARGUMENTS (decl);
4095 tree argtype = TYPE_ARG_TYPES (type);
4097 while (arg && argtype)
4099 if (!FUNCTION_PARAMETER_PACK_P (arg)
4100 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4102 /* This is a PARM_DECL that contains unexpanded parameter
4103 packs. We have already complained about this in the
4104 check_for_bare_parameter_packs call, so just replace
4105 these types with ERROR_MARK_NODE. */
4106 TREE_TYPE (arg) = error_mark_node;
4107 TREE_VALUE (argtype) = error_mark_node;
4110 arg = TREE_CHAIN (arg);
4111 argtype = TREE_CHAIN (argtype);
4114 /* Check for bare parameter packs in the return type and the
4115 exception specifiers. */
4116 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4117 /* Errors were already issued, set return type to int
4118 as the frontend doesn't expect error_mark_node as
4120 TREE_TYPE (type) = integer_type_node;
4121 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4122 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4124 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4126 TREE_TYPE (decl) = error_mark_node;
4127 return error_mark_node;
4131 return process_partial_specialization (decl);
4133 args = current_template_args ();
4136 || TREE_CODE (ctx) == FUNCTION_DECL
4137 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4138 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4140 if (DECL_LANG_SPECIFIC (decl)
4141 && DECL_TEMPLATE_INFO (decl)
4142 && DECL_TI_TEMPLATE (decl))
4143 tmpl = DECL_TI_TEMPLATE (decl);
4144 /* If DECL is a TYPE_DECL for a class-template, then there won't
4145 be DECL_LANG_SPECIFIC. The information equivalent to
4146 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4147 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4148 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4149 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4151 /* Since a template declaration already existed for this
4152 class-type, we must be redeclaring it here. Make sure
4153 that the redeclaration is valid. */
4154 redeclare_class_template (TREE_TYPE (decl),
4155 current_template_parms);
4156 /* We don't need to create a new TEMPLATE_DECL; just use the
4157 one we already had. */
4158 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4162 tmpl = build_template_decl (decl, current_template_parms,
4166 if (DECL_LANG_SPECIFIC (decl)
4167 && DECL_TEMPLATE_SPECIALIZATION (decl))
4169 /* A specialization of a member template of a template
4171 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4172 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4173 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4179 tree a, t, current, parms;
4181 tree tinfo = get_template_info (decl);
4185 error ("template definition of non-template %q#D", decl);
4186 return error_mark_node;
4189 tmpl = TI_TEMPLATE (tinfo);
4191 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4192 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4193 && DECL_TEMPLATE_SPECIALIZATION (decl)
4194 && DECL_MEMBER_TEMPLATE_P (tmpl))
4198 /* The declaration is a specialization of a member
4199 template, declared outside the class. Therefore, the
4200 innermost template arguments will be NULL, so we
4201 replace them with the arguments determined by the
4202 earlier call to check_explicit_specialization. */
4203 args = DECL_TI_ARGS (decl);
4206 = build_template_decl (decl, current_template_parms,
4208 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4209 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4210 DECL_TI_TEMPLATE (decl) = new_tmpl;
4211 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4212 DECL_TEMPLATE_INFO (new_tmpl)
4213 = tree_cons (tmpl, args, NULL_TREE);
4215 register_specialization (new_tmpl,
4216 most_general_template (tmpl),
4222 /* Make sure the template headers we got make sense. */
4224 parms = DECL_TEMPLATE_PARMS (tmpl);
4225 i = TMPL_PARMS_DEPTH (parms);
4226 if (TMPL_ARGS_DEPTH (args) != i)
4228 error ("expected %d levels of template parms for %q#D, got %d",
4229 i, decl, TMPL_ARGS_DEPTH (args));
4232 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4234 a = TMPL_ARGS_LEVEL (args, i);
4235 t = INNERMOST_TEMPLATE_PARMS (parms);
4237 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4239 if (current == decl)
4240 error ("got %d template parameters for %q#D",
4241 TREE_VEC_LENGTH (a), decl);
4243 error ("got %d template parameters for %q#T",
4244 TREE_VEC_LENGTH (a), current);
4245 error (" but %d required", TREE_VEC_LENGTH (t));
4246 return error_mark_node;
4249 if (current == decl)
4252 current = (TYPE_P (current)
4253 ? TYPE_CONTEXT (current)
4254 : DECL_CONTEXT (current));
4257 /* Check that the parms are used in the appropriate qualifying scopes
4258 in the declarator. */
4259 if (!comp_template_args
4261 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4264 template arguments to %qD do not match original template %qD",
4265 decl, DECL_TEMPLATE_RESULT (tmpl));
4266 if (!uses_template_parms (TI_ARGS (tinfo)))
4267 inform (input_location, "use template<> for an explicit specialization");
4268 /* Avoid crash in import_export_decl. */
4269 DECL_INTERFACE_KNOWN (decl) = 1;
4270 return error_mark_node;
4274 DECL_TEMPLATE_RESULT (tmpl) = decl;
4275 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4277 /* Push template declarations for global functions and types. Note
4278 that we do not try to push a global template friend declared in a
4279 template class; such a thing may well depend on the template
4280 parameters of the class. */
4281 if (new_template_p && !ctx
4282 && !(is_friend && template_class_depth (current_class_type) > 0))
4284 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4285 if (tmpl == error_mark_node)
4286 return error_mark_node;
4288 /* Hide template friend classes that haven't been declared yet. */
4289 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4291 DECL_ANTICIPATED (tmpl) = 1;
4292 DECL_FRIEND_P (tmpl) = 1;
4298 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4301 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4302 if (DECL_CONV_FN_P (tmpl))
4304 int depth = TMPL_PARMS_DEPTH (parms);
4306 /* It is a conversion operator. See if the type converted to
4307 depends on innermost template operands. */
4309 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4311 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4314 /* Give template template parms a DECL_CONTEXT of the template
4315 for which they are a parameter. */
4316 parms = INNERMOST_TEMPLATE_PARMS (parms);
4317 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4319 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4320 if (TREE_CODE (parm) == TEMPLATE_DECL)
4321 DECL_CONTEXT (parm) = tmpl;
4325 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4326 back to its most general template. If TMPL is a specialization,
4327 ARGS may only have the innermost set of arguments. Add the missing
4328 argument levels if necessary. */
4329 if (DECL_TEMPLATE_INFO (tmpl))
4330 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4332 info = tree_cons (tmpl, args, NULL_TREE);
4334 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4335 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4336 else if (DECL_LANG_SPECIFIC (decl))
4337 DECL_TEMPLATE_INFO (decl) = info;
4339 return DECL_TEMPLATE_RESULT (tmpl);
4343 push_template_decl (tree decl)
4345 return push_template_decl_real (decl, false);
4348 /* Called when a class template TYPE is redeclared with the indicated
4349 template PARMS, e.g.:
4351 template <class T> struct S;
4352 template <class T> struct S {}; */
4355 redeclare_class_template (tree type, tree parms)
4361 if (!TYPE_TEMPLATE_INFO (type))
4363 error ("%qT is not a template type", type);
4367 tmpl = TYPE_TI_TEMPLATE (type);
4368 if (!PRIMARY_TEMPLATE_P (tmpl))
4369 /* The type is nested in some template class. Nothing to worry
4370 about here; there are no new template parameters for the nested
4376 error ("template specifiers not specified in declaration of %qD",
4381 parms = INNERMOST_TEMPLATE_PARMS (parms);
4382 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4384 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4386 error ("redeclared with %d template parameter(s)",
4387 TREE_VEC_LENGTH (parms));
4388 inform (input_location, "previous declaration %q+D used %d template parameter(s)",
4389 tmpl, TREE_VEC_LENGTH (tmpl_parms));
4393 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4400 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4401 || TREE_VEC_ELT (parms, i) == error_mark_node)
4404 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4405 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4406 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4407 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4409 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
4411 if (tmpl_parm != error_mark_node
4412 && (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
4413 || (TREE_CODE (tmpl_parm) != TYPE_DECL
4414 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
4415 || (TREE_CODE (tmpl_parm) != PARM_DECL
4416 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
4417 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
4418 || (TREE_CODE (tmpl_parm) == PARM_DECL
4419 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
4420 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))))))
4422 error ("template parameter %q+#D", tmpl_parm);
4423 error ("redeclared here as %q#D", parm);
4427 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
4429 /* We have in [temp.param]:
4431 A template-parameter may not be given default arguments
4432 by two different declarations in the same scope. */
4433 error_at (input_location, "redefinition of default argument for %q#D", parm);
4434 inform (DECL_SOURCE_LOCATION (tmpl_parm),
4435 "original definition appeared here");
4439 if (parm_default != NULL_TREE)
4440 /* Update the previous template parameters (which are the ones
4441 that will really count) with the new default value. */
4442 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
4443 else if (tmpl_default != NULL_TREE)
4444 /* Update the new parameters, too; they'll be used as the
4445 parameters for any members. */
4446 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
4452 /* Simplify EXPR if it is a non-dependent expression. Returns the
4453 (possibly simplified) expression. */
4456 fold_non_dependent_expr (tree expr)
4458 if (expr == NULL_TREE)
4461 /* If we're in a template, but EXPR isn't value dependent, simplify
4462 it. We're supposed to treat:
4464 template <typename T> void f(T[1 + 1]);
4465 template <typename T> void f(T[2]);
4467 as two declarations of the same function, for example. */
4468 if (processing_template_decl
4469 && !type_dependent_expression_p (expr)
4470 && !value_dependent_expression_p (expr))
4472 HOST_WIDE_INT saved_processing_template_decl;
4474 saved_processing_template_decl = processing_template_decl;
4475 processing_template_decl = 0;
4476 expr = tsubst_copy_and_build (expr,
4479 /*in_decl=*/NULL_TREE,
4480 /*function_p=*/false,
4481 /*integral_constant_expression_p=*/true);
4482 processing_template_decl = saved_processing_template_decl;
4487 /* EXPR is an expression which is used in a constant-expression context.
4488 For instance, it could be a VAR_DECL with a constant initializer.
4489 Extract the innermost constant expression.
4491 This is basically a more powerful version of
4492 integral_constant_value, which can be used also in templates where
4493 initializers can maintain a syntactic rather than semantic form
4494 (even if they are non-dependent, for access-checking purposes). */
4497 fold_decl_constant_value (tree expr)
4499 tree const_expr = expr;
4502 expr = fold_non_dependent_expr (const_expr);
4503 const_expr = integral_constant_value (expr);
4505 while (expr != const_expr);
4510 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
4511 must be a function or a pointer-to-function type, as specified
4512 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
4513 and check that the resulting function has external linkage. */
4516 convert_nontype_argument_function (tree type, tree expr)
4521 fn = instantiate_type (type, fns, tf_none);
4522 if (fn == error_mark_node)
4523 return error_mark_node;
4526 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
4527 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
4528 if (TREE_CODE (fn_no_ptr) == BASELINK)
4529 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
4531 /* [temp.arg.nontype]/1
4533 A template-argument for a non-type, non-template template-parameter
4536 -- the address of an object or function with external linkage. */
4537 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
4539 error ("%qE is not a valid template argument for type %qT "
4540 "because function %qD has not external linkage",
4541 expr, type, fn_no_ptr);
4548 /* Attempt to convert the non-type template parameter EXPR to the
4549 indicated TYPE. If the conversion is successful, return the
4550 converted value. If the conversion is unsuccessful, return
4551 NULL_TREE if we issued an error message, or error_mark_node if we
4552 did not. We issue error messages for out-and-out bad template
4553 parameters, but not simply because the conversion failed, since we
4554 might be just trying to do argument deduction. Both TYPE and EXPR
4555 must be non-dependent.
4557 The conversion follows the special rules described in
4558 [temp.arg.nontype], and it is much more strict than an implicit
4561 This function is called twice for each template argument (see
4562 lookup_template_class for a more accurate description of this
4563 problem). This means that we need to handle expressions which
4564 are not valid in a C++ source, but can be created from the
4565 first call (for instance, casts to perform conversions). These
4566 hacks can go away after we fix the double coercion problem. */
4569 convert_nontype_argument (tree type, tree expr)
4573 /* Detect immediately string literals as invalid non-type argument.
4574 This special-case is not needed for correctness (we would easily
4575 catch this later), but only to provide better diagnostic for this
4576 common user mistake. As suggested by DR 100, we do not mention
4577 linkage issues in the diagnostic as this is not the point. */
4578 if (TREE_CODE (expr) == STRING_CST)
4580 error ("%qE is not a valid template argument for type %qT "
4581 "because string literals can never be used in this context",
4586 /* If we are in a template, EXPR may be non-dependent, but still
4587 have a syntactic, rather than semantic, form. For example, EXPR
4588 might be a SCOPE_REF, rather than the VAR_DECL to which the
4589 SCOPE_REF refers. Preserving the qualifying scope is necessary
4590 so that access checking can be performed when the template is
4591 instantiated -- but here we need the resolved form so that we can
4592 convert the argument. */
4593 expr = fold_non_dependent_expr (expr);
4594 if (error_operand_p (expr))
4595 return error_mark_node;
4596 expr_type = TREE_TYPE (expr);
4598 /* HACK: Due to double coercion, we can get a
4599 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
4600 which is the tree that we built on the first call (see
4601 below when coercing to reference to object or to reference to
4602 function). We just strip everything and get to the arg.
4603 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
4605 if (TREE_CODE (expr) == NOP_EXPR)
4607 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
4609 /* ??? Maybe we could use convert_from_reference here, but we
4610 would need to relax its constraints because the NOP_EXPR
4611 could actually change the type to something more cv-qualified,
4612 and this is not folded by convert_from_reference. */
4613 tree addr = TREE_OPERAND (expr, 0);
4614 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
4615 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
4616 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
4617 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4618 (TREE_TYPE (expr_type),
4619 TREE_TYPE (TREE_TYPE (addr))));
4621 expr = TREE_OPERAND (addr, 0);
4622 expr_type = TREE_TYPE (expr);
4625 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
4626 parameter is a pointer to object, through decay and
4627 qualification conversion. Let's strip everything. */
4628 else if (TYPE_PTROBV_P (type))
4631 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
4632 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
4633 /* Skip the ADDR_EXPR only if it is part of the decay for
4634 an array. Otherwise, it is part of the original argument
4635 in the source code. */
4636 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
4637 expr = TREE_OPERAND (expr, 0);
4638 expr_type = TREE_TYPE (expr);
4642 /* [temp.arg.nontype]/5, bullet 1
4644 For a non-type template-parameter of integral or enumeration type,
4645 integral promotions (_conv.prom_) and integral conversions
4646 (_conv.integral_) are applied. */
4647 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
4649 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (expr_type))
4650 return error_mark_node;
4652 expr = fold_decl_constant_value (expr);
4653 /* Notice that there are constant expressions like '4 % 0' which
4654 do not fold into integer constants. */
4655 if (TREE_CODE (expr) != INTEGER_CST)
4657 error ("%qE is not a valid template argument for type %qT "
4658 "because it is a non-constant expression", expr, type);
4662 /* At this point, an implicit conversion does what we want,
4663 because we already know that the expression is of integral
4665 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
4666 if (expr == error_mark_node)
4667 return error_mark_node;
4669 /* Conversion was allowed: fold it to a bare integer constant. */
4672 /* [temp.arg.nontype]/5, bullet 2
4674 For a non-type template-parameter of type pointer to object,
4675 qualification conversions (_conv.qual_) and the array-to-pointer
4676 conversion (_conv.array_) are applied. */
4677 else if (TYPE_PTROBV_P (type))
4679 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
4681 A template-argument for a non-type, non-template template-parameter
4682 shall be one of: [...]
4684 -- the name of a non-type template-parameter;
4685 -- the address of an object or function with external linkage, [...]
4686 expressed as "& id-expression" where the & is optional if the name
4687 refers to a function or array, or if the corresponding
4688 template-parameter is a reference.
4690 Here, we do not care about functions, as they are invalid anyway
4691 for a parameter of type pointer-to-object. */
4693 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
4694 /* Non-type template parameters are OK. */
4696 else if (TREE_CODE (expr) != ADDR_EXPR
4697 && TREE_CODE (expr_type) != ARRAY_TYPE)
4699 if (TREE_CODE (expr) == VAR_DECL)
4701 error ("%qD is not a valid template argument "
4702 "because %qD is a variable, not the address of "
4707 /* Other values, like integer constants, might be valid
4708 non-type arguments of some other type. */
4709 return error_mark_node;
4715 decl = ((TREE_CODE (expr) == ADDR_EXPR)
4716 ? TREE_OPERAND (expr, 0) : expr);
4717 if (TREE_CODE (decl) != VAR_DECL)
4719 error ("%qE is not a valid template argument of type %qT "
4720 "because %qE is not a variable",
4724 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
4726 error ("%qE is not a valid template argument of type %qT "
4727 "because %qD does not have external linkage",
4733 expr = decay_conversion (expr);
4734 if (expr == error_mark_node)
4735 return error_mark_node;
4737 expr = perform_qualification_conversions (type, expr);
4738 if (expr == error_mark_node)
4739 return error_mark_node;
4741 /* [temp.arg.nontype]/5, bullet 3
4743 For a non-type template-parameter of type reference to object, no
4744 conversions apply. The type referred to by the reference may be more
4745 cv-qualified than the (otherwise identical) type of the
4746 template-argument. The template-parameter is bound directly to the
4747 template-argument, which must be an lvalue. */
4748 else if (TYPE_REF_OBJ_P (type))
4750 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
4752 return error_mark_node;
4754 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
4756 error ("%qE is not a valid template argument for type %qT "
4757 "because of conflicts in cv-qualification", expr, type);
4761 if (!real_lvalue_p (expr))
4763 error ("%qE is not a valid template argument for type %qT "
4764 "because it is not an lvalue", expr, type);
4768 /* [temp.arg.nontype]/1
4770 A template-argument for a non-type, non-template template-parameter
4771 shall be one of: [...]
4773 -- the address of an object or function with external linkage. */
4774 if (!DECL_EXTERNAL_LINKAGE_P (expr))
4776 error ("%qE is not a valid template argument for type %qT "
4777 "because object %qD has not external linkage",
4782 expr = build_nop (type, build_address (expr));
4784 /* [temp.arg.nontype]/5, bullet 4
4786 For a non-type template-parameter of type pointer to function, only
4787 the function-to-pointer conversion (_conv.func_) is applied. If the
4788 template-argument represents a set of overloaded functions (or a
4789 pointer to such), the matching function is selected from the set
4791 else if (TYPE_PTRFN_P (type))
4793 /* If the argument is a template-id, we might not have enough
4794 context information to decay the pointer. */
4795 if (!type_unknown_p (expr_type))
4797 expr = decay_conversion (expr);
4798 if (expr == error_mark_node)
4799 return error_mark_node;
4802 expr = convert_nontype_argument_function (type, expr);
4803 if (!expr || expr == error_mark_node)
4806 if (TREE_CODE (expr) != ADDR_EXPR)
4808 error ("%qE is not a valid template argument for type %qT", expr, type);
4809 error ("it must be the address of a function with external linkage");
4813 /* [temp.arg.nontype]/5, bullet 5
4815 For a non-type template-parameter of type reference to function, no
4816 conversions apply. If the template-argument represents a set of
4817 overloaded functions, the matching function is selected from the set
4819 else if (TYPE_REFFN_P (type))
4821 if (TREE_CODE (expr) == ADDR_EXPR)
4823 error ("%qE is not a valid template argument for type %qT "
4824 "because it is a pointer", expr, type);
4825 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
4829 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
4830 if (!expr || expr == error_mark_node)
4833 expr = build_nop (type, build_address (expr));
4835 /* [temp.arg.nontype]/5, bullet 6
4837 For a non-type template-parameter of type pointer to member function,
4838 no conversions apply. If the template-argument represents a set of
4839 overloaded member functions, the matching member function is selected
4840 from the set (_over.over_). */
4841 else if (TYPE_PTRMEMFUNC_P (type))
4843 expr = instantiate_type (type, expr, tf_none);
4844 if (expr == error_mark_node)
4845 return error_mark_node;
4847 /* There is no way to disable standard conversions in
4848 resolve_address_of_overloaded_function (called by
4849 instantiate_type). It is possible that the call succeeded by
4850 converting &B::I to &D::I (where B is a base of D), so we need
4851 to reject this conversion here.
4853 Actually, even if there was a way to disable standard conversions,
4854 it would still be better to reject them here so that we can
4855 provide a superior diagnostic. */
4856 if (!same_type_p (TREE_TYPE (expr), type))
4858 /* Make sure we are just one standard conversion off. */
4859 gcc_assert (can_convert (type, TREE_TYPE (expr)));
4860 error ("%qE is not a valid template argument for type %qT "
4861 "because it is of type %qT", expr, type,
4863 inform (input_location, "standard conversions are not allowed in this context");
4867 /* [temp.arg.nontype]/5, bullet 7
4869 For a non-type template-parameter of type pointer to data member,
4870 qualification conversions (_conv.qual_) are applied. */
4871 else if (TYPE_PTRMEM_P (type))
4873 expr = perform_qualification_conversions (type, expr);
4874 if (expr == error_mark_node)
4877 /* A template non-type parameter must be one of the above. */
4881 /* Sanity check: did we actually convert the argument to the
4883 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
4887 /* Subroutine of coerce_template_template_parms, which returns 1 if
4888 PARM_PARM and ARG_PARM match using the rule for the template
4889 parameters of template template parameters. Both PARM and ARG are
4890 template parameters; the rest of the arguments are the same as for
4891 coerce_template_template_parms.
4894 coerce_template_template_parm (tree parm,
4896 tsubst_flags_t complain,
4900 if (arg == NULL_TREE || arg == error_mark_node
4901 || parm == NULL_TREE || parm == error_mark_node)
4904 if (TREE_CODE (arg) != TREE_CODE (parm))
4907 switch (TREE_CODE (parm))
4910 /* We encounter instantiations of templates like
4911 template <template <template <class> class> class TT>
4914 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
4915 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
4917 if (!coerce_template_template_parms
4918 (parmparm, argparm, complain, in_decl, outer_args))
4924 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
4925 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
4926 /* Argument is a parameter pack but parameter is not. */
4931 /* The tsubst call is used to handle cases such as
4933 template <int> class C {};
4934 template <class T, template <T> class TT> class D {};
4937 i.e. the parameter list of TT depends on earlier parameters. */
4938 if (!uses_template_parms (TREE_TYPE (arg))
4940 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
4944 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
4945 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
4946 /* Argument is a parameter pack but parameter is not. */
4959 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
4960 template template parameters. Both PARM_PARMS and ARG_PARMS are
4961 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
4964 Consider the example:
4965 template <class T> class A;
4966 template<template <class U> class TT> class B;
4968 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
4969 the parameters to A, and OUTER_ARGS contains A. */
4972 coerce_template_template_parms (tree parm_parms,
4974 tsubst_flags_t complain,
4978 int nparms, nargs, i;
4982 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
4983 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
4985 nparms = TREE_VEC_LENGTH (parm_parms);
4986 nargs = TREE_VEC_LENGTH (arg_parms);
4988 /* Determine whether we have a parameter pack at the end of the
4989 template template parameter's template parameter list. */
4990 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
4992 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
4994 if (parm == error_mark_node)
4997 switch (TREE_CODE (parm))
5001 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5006 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5016 && !(variadic_p && nargs >= nparms - 1))
5019 /* Check all of the template parameters except the parameter pack at
5020 the end (if any). */
5021 for (i = 0; i < nparms - variadic_p; ++i)
5023 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
5024 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5027 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5028 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5030 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5038 /* Check each of the template parameters in the template
5039 argument against the template parameter pack at the end of
5040 the template template parameter. */
5041 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
5044 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5046 for (; i < nargs; ++i)
5048 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5051 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5053 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5062 /* Verifies that the deduced template arguments (in TARGS) for the
5063 template template parameters (in TPARMS) represent valid bindings,
5064 by comparing the template parameter list of each template argument
5065 to the template parameter list of its corresponding template
5066 template parameter, in accordance with DR150. This
5067 routine can only be called after all template arguments have been
5068 deduced. It will return TRUE if all of the template template
5069 parameter bindings are okay, FALSE otherwise. */
5071 template_template_parm_bindings_ok_p (tree tparms, tree targs)
5073 int i, ntparms = TREE_VEC_LENGTH (tparms);
5076 /* We're dealing with template parms in this process. */
5077 ++processing_template_decl;
5079 targs = INNERMOST_TEMPLATE_ARGS (targs);
5081 for (i = 0; i < ntparms; ++i)
5083 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
5084 tree targ = TREE_VEC_ELT (targs, i);
5086 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
5088 tree packed_args = NULL_TREE;
5091 if (ARGUMENT_PACK_P (targ))
5093 /* Look inside the argument pack. */
5094 packed_args = ARGUMENT_PACK_ARGS (targ);
5095 len = TREE_VEC_LENGTH (packed_args);
5098 for (idx = 0; idx < len; ++idx)
5100 tree targ_parms = NULL_TREE;
5103 /* Extract the next argument from the argument
5105 targ = TREE_VEC_ELT (packed_args, idx);
5107 if (PACK_EXPANSION_P (targ))
5108 /* Look at the pattern of the pack expansion. */
5109 targ = PACK_EXPANSION_PATTERN (targ);
5111 /* Extract the template parameters from the template
5113 if (TREE_CODE (targ) == TEMPLATE_DECL)
5114 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
5115 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
5116 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
5118 /* Verify that we can coerce the template template
5119 parameters from the template argument to the template
5120 parameter. This requires an exact match. */
5122 && !coerce_template_template_parms
5123 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
5138 --processing_template_decl;
5142 /* Convert the indicated template ARG as necessary to match the
5143 indicated template PARM. Returns the converted ARG, or
5144 error_mark_node if the conversion was unsuccessful. Error and
5145 warning messages are issued under control of COMPLAIN. This
5146 conversion is for the Ith parameter in the parameter list. ARGS is
5147 the full set of template arguments deduced so far. */
5150 convert_template_argument (tree parm,
5153 tsubst_flags_t complain,
5159 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
5161 if (TREE_CODE (arg) == TREE_LIST
5162 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
5164 /* The template argument was the name of some
5165 member function. That's usually
5166 invalid, but static members are OK. In any
5167 case, grab the underlying fields/functions
5168 and issue an error later if required. */
5169 orig_arg = TREE_VALUE (arg);
5170 TREE_TYPE (arg) = unknown_type_node;
5175 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
5176 requires_type = (TREE_CODE (parm) == TYPE_DECL
5177 || requires_tmpl_type);
5179 /* When determining whether an argument pack expansion is a template,
5180 look at the pattern. */
5181 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
5182 arg = PACK_EXPANSION_PATTERN (arg);
5185 ((TREE_CODE (arg) == TEMPLATE_DECL
5186 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
5187 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5188 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
5191 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5192 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
5193 arg = TYPE_STUB_DECL (arg);
5195 is_type = TYPE_P (arg) || is_tmpl_type;
5197 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
5198 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
5200 permerror (input_location, "to refer to a type member of a template parameter, "
5201 "use %<typename %E%>", orig_arg);
5203 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
5204 TREE_OPERAND (arg, 1),
5206 complain & tf_error);
5210 if (is_type != requires_type)
5214 if (complain & tf_error)
5216 error ("type/value mismatch at argument %d in template "
5217 "parameter list for %qD",
5220 error (" expected a constant of type %qT, got %qT",
5222 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
5223 else if (requires_tmpl_type)
5224 error (" expected a class template, got %qE", orig_arg);
5226 error (" expected a type, got %qE", orig_arg);
5229 return error_mark_node;
5231 if (is_tmpl_type ^ requires_tmpl_type)
5233 if (in_decl && (complain & tf_error))
5235 error ("type/value mismatch at argument %d in template "
5236 "parameter list for %qD",
5239 error (" expected a type, got %qT", DECL_NAME (arg));
5241 error (" expected a class template, got %qT", orig_arg);
5243 return error_mark_node;
5248 if (requires_tmpl_type)
5250 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
5251 /* The number of argument required is not known yet.
5252 Just accept it for now. */
5253 val = TREE_TYPE (arg);
5256 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5259 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5261 if (coerce_template_template_parms (parmparm, argparm,
5267 /* TEMPLATE_TEMPLATE_PARM node is preferred over
5269 if (val != error_mark_node)
5271 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
5272 val = TREE_TYPE (val);
5273 else if (TREE_CODE (val) == TYPE_PACK_EXPANSION
5274 && DECL_TEMPLATE_TEMPLATE_PARM_P (arg))
5276 val = TREE_TYPE (arg);
5277 val = make_pack_expansion (val);
5283 if (in_decl && (complain & tf_error))
5285 error ("type/value mismatch at argument %d in "
5286 "template parameter list for %qD",
5288 error (" expected a template of type %qD, got %qD",
5292 val = error_mark_node;
5298 /* We only form one instance of each template specialization.
5299 Therefore, if we use a non-canonical variant (i.e., a
5300 typedef), any future messages referring to the type will use
5301 the typedef, which is confusing if those future uses do not
5302 themselves also use the typedef. */
5304 val = strip_typedefs (val);
5308 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
5310 if (invalid_nontype_parm_type_p (t, complain))
5311 return error_mark_node;
5313 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
5315 if (same_type_p (t, TREE_TYPE (orig_arg)))
5319 /* Not sure if this is reachable, but it doesn't hurt
5321 error ("type mismatch in nontype parameter pack");
5322 val = error_mark_node;
5325 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
5326 /* We used to call digest_init here. However, digest_init
5327 will report errors, which we don't want when complain
5328 is zero. More importantly, digest_init will try too
5329 hard to convert things: for example, `0' should not be
5330 converted to pointer type at this point according to
5331 the standard. Accepting this is not merely an
5332 extension, since deciding whether or not these
5333 conversions can occur is part of determining which
5334 function template to call, or whether a given explicit
5335 argument specification is valid. */
5336 val = convert_nontype_argument (t, orig_arg);
5340 if (val == NULL_TREE)
5341 val = error_mark_node;
5342 else if (val == error_mark_node && (complain & tf_error))
5343 error ("could not convert template argument %qE to %qT", orig_arg, t);
5349 /* Coerces the remaining template arguments in INNER_ARGS (from
5350 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
5351 Returns the coerced argument pack. PARM_IDX is the position of this
5352 parameter in the template parameter list. ARGS is the original
5353 template argument list. */
5355 coerce_template_parameter_pack (tree parms,
5363 tsubst_flags_t complain)
5365 tree parm = TREE_VEC_ELT (parms, parm_idx);
5366 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5369 tree packed_types = NULL_TREE;
5371 if (arg_idx > nargs)
5374 packed_args = make_tree_vec (nargs - arg_idx);
5376 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
5377 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
5379 /* When the template parameter is a non-type template
5380 parameter pack whose type uses parameter packs, we need
5381 to look at each of the template arguments
5382 separately. Build a vector of the types for these
5383 non-type template parameters in PACKED_TYPES. */
5385 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
5386 packed_types = tsubst_pack_expansion (expansion, args,
5389 if (packed_types == error_mark_node)
5390 return error_mark_node;
5392 /* Check that we have the right number of arguments. */
5394 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
5395 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
5398 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
5399 error ("wrong number of template arguments (%d, should be %d)",
5400 nargs, needed_parms);
5401 return error_mark_node;
5404 /* If we aren't able to check the actual arguments now
5405 (because they haven't been expanded yet), we can at least
5406 verify that all of the types used for the non-type
5407 template parameter pack are, in fact, valid for non-type
5408 template parameters. */
5410 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
5412 int j, len = TREE_VEC_LENGTH (packed_types);
5413 for (j = 0; j < len; ++j)
5415 tree t = TREE_VEC_ELT (packed_types, j);
5416 if (invalid_nontype_parm_type_p (t, complain))
5417 return error_mark_node;
5422 /* Convert the remaining arguments, which will be a part of the
5423 parameter pack "parm". */
5424 for (; arg_idx < nargs; ++arg_idx)
5426 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
5427 tree actual_parm = TREE_VALUE (parm);
5429 if (packed_types && !PACK_EXPANSION_P (arg))
5431 /* When we have a vector of types (corresponding to the
5432 non-type template parameter pack that uses parameter
5433 packs in its type, as mention above), and the
5434 argument is not an expansion (which expands to a
5435 currently unknown number of arguments), clone the
5436 parm and give it the next type in PACKED_TYPES. */
5437 actual_parm = copy_node (actual_parm);
5438 TREE_TYPE (actual_parm) =
5439 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
5442 if (arg != error_mark_node)
5443 arg = convert_template_argument (actual_parm,
5444 arg, new_args, complain, parm_idx,
5446 if (arg == error_mark_node)
5448 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
5451 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
5452 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
5453 argument_pack = make_node (TYPE_ARGUMENT_PACK);
5456 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
5457 TREE_TYPE (argument_pack)
5458 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
5459 TREE_CONSTANT (argument_pack) = 1;
5462 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
5463 return argument_pack;
5466 /* Convert all template arguments to their appropriate types, and
5467 return a vector containing the innermost resulting template
5468 arguments. If any error occurs, return error_mark_node. Error and
5469 warning messages are issued under control of COMPLAIN.
5471 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
5472 for arguments not specified in ARGS. Otherwise, if
5473 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
5474 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
5475 USE_DEFAULT_ARGS is false, then all arguments must be specified in
5479 coerce_template_parms (tree parms,
5482 tsubst_flags_t complain,
5483 bool require_all_args,
5484 bool use_default_args)
5486 int nparms, nargs, parm_idx, arg_idx, lost = 0;
5489 tree new_inner_args;
5490 int saved_unevaluated_operand;
5491 int saved_inhibit_evaluation_warnings;
5493 /* When used as a boolean value, indicates whether this is a
5494 variadic template parameter list. Since it's an int, we can also
5495 subtract it from nparms to get the number of non-variadic
5499 nparms = TREE_VEC_LENGTH (parms);
5501 /* Determine if there are any parameter packs. */
5502 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
5504 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
5505 if (template_parameter_pack_p (tparm))
5509 inner_args = INNERMOST_TEMPLATE_ARGS (args);
5510 /* If there are 0 or 1 parameter packs, we need to expand any argument
5511 packs so that we can deduce a parameter pack from some non-packed args
5512 followed by an argument pack, as in variadic85.C. If there are more
5513 than that, we need to leave argument packs intact so the arguments are
5514 assigned to the right parameter packs. This should only happen when
5515 dealing with a nested class inside a partial specialization of a class
5516 template, as in variadic92.C. */
5517 if (variadic_p <= 1)
5518 inner_args = expand_template_argument_pack (inner_args);
5520 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5521 if ((nargs > nparms && !variadic_p)
5522 || (nargs < nparms - variadic_p
5524 && (!use_default_args
5525 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
5526 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
5528 if (complain & tf_error)
5530 const char *or_more = "";
5533 or_more = " or more";
5537 error ("wrong number of template arguments (%d, should be %d%s)",
5538 nargs, nparms, or_more);
5541 error ("provided for %q+D", in_decl);
5544 return error_mark_node;
5547 /* We need to evaluate the template arguments, even though this
5548 template-id may be nested within a "sizeof". */
5549 saved_unevaluated_operand = cp_unevaluated_operand;
5550 cp_unevaluated_operand = 0;
5551 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
5552 c_inhibit_evaluation_warnings = 0;
5553 new_inner_args = make_tree_vec (nparms);
5554 new_args = add_outermost_template_args (args, new_inner_args);
5555 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
5560 /* Get the Ith template parameter. */
5561 parm = TREE_VEC_ELT (parms, parm_idx);
5563 if (parm == error_mark_node)
5565 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
5569 /* Calculate the next argument. */
5570 if (arg_idx < nargs)
5571 arg = TREE_VEC_ELT (inner_args, arg_idx);
5575 if (template_parameter_pack_p (TREE_VALUE (parm))
5576 && !(arg && ARGUMENT_PACK_P (arg)))
5578 /* All remaining arguments will be placed in the
5579 template parameter pack PARM. */
5580 arg = coerce_template_parameter_pack (parms, parm_idx, args,
5581 inner_args, arg_idx,
5585 /* Store this argument. */
5586 if (arg == error_mark_node)
5588 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
5590 /* We are done with all of the arguments. */
5597 if (PACK_EXPANSION_P (arg))
5599 if (complain & tf_error)
5601 /* FIXME this restriction was removed by N2555; see
5603 /* If ARG is a pack expansion, but PARM is not a
5604 template parameter pack (if it were, we would have
5605 handled it above), we're trying to expand into a
5606 fixed-length argument list. */
5607 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
5608 sorry ("cannot expand %<%E%> into a fixed-length "
5609 "argument list", arg);
5611 sorry ("cannot expand %<%T%> into a fixed-length "
5612 "argument list", arg);
5614 return error_mark_node;
5617 else if (require_all_args)
5618 /* There must be a default arg in this case. */
5619 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
5624 if (arg == error_mark_node)
5626 if (complain & tf_error)
5627 error ("template argument %d is invalid", arg_idx + 1);
5630 /* This only occurs if there was an error in the template
5631 parameter list itself (which we would already have
5632 reported) that we are trying to recover from, e.g., a class
5633 template with a parameter list such as
5634 template<typename..., typename>. */
5635 return error_mark_node;
5637 arg = convert_template_argument (TREE_VALUE (parm),
5638 arg, new_args, complain,
5641 if (arg == error_mark_node)
5643 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
5645 cp_unevaluated_operand = saved_unevaluated_operand;
5646 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
5649 return error_mark_node;
5651 return new_inner_args;
5654 /* Returns 1 if template args OT and NT are equivalent. */
5657 template_args_equal (tree ot, tree nt)
5662 if (TREE_CODE (nt) == TREE_VEC)
5663 /* For member templates */
5664 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
5665 else if (PACK_EXPANSION_P (ot))
5666 return PACK_EXPANSION_P (nt)
5667 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
5668 PACK_EXPANSION_PATTERN (nt));
5669 else if (ARGUMENT_PACK_P (ot))
5674 if (!ARGUMENT_PACK_P (nt))
5677 opack = ARGUMENT_PACK_ARGS (ot);
5678 npack = ARGUMENT_PACK_ARGS (nt);
5679 len = TREE_VEC_LENGTH (opack);
5680 if (TREE_VEC_LENGTH (npack) != len)
5682 for (i = 0; i < len; ++i)
5683 if (!template_args_equal (TREE_VEC_ELT (opack, i),
5684 TREE_VEC_ELT (npack, i)))
5688 else if (TYPE_P (nt))
5689 return TYPE_P (ot) && same_type_p (ot, nt);
5690 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
5693 return cp_tree_equal (ot, nt);
5696 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
5697 of template arguments. Returns 0 otherwise. */
5700 comp_template_args (tree oldargs, tree newargs)
5704 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
5707 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
5709 tree nt = TREE_VEC_ELT (newargs, i);
5710 tree ot = TREE_VEC_ELT (oldargs, i);
5712 if (! template_args_equal (ot, nt))
5719 add_pending_template (tree d)
5721 tree ti = (TYPE_P (d)
5722 ? CLASSTYPE_TEMPLATE_INFO (d)
5723 : DECL_TEMPLATE_INFO (d));
5724 struct pending_template *pt;
5727 if (TI_PENDING_TEMPLATE_FLAG (ti))
5730 /* We are called both from instantiate_decl, where we've already had a
5731 tinst_level pushed, and instantiate_template, where we haven't.
5733 level = !current_tinst_level || current_tinst_level->decl != d;
5736 push_tinst_level (d);
5738 pt = GGC_NEW (struct pending_template);
5740 pt->tinst = current_tinst_level;
5741 if (last_pending_template)
5742 last_pending_template->next = pt;
5744 pending_templates = pt;
5746 last_pending_template = pt;
5748 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
5755 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
5756 ARGLIST. Valid choices for FNS are given in the cp-tree.def
5757 documentation for TEMPLATE_ID_EXPR. */
5760 lookup_template_function (tree fns, tree arglist)
5764 if (fns == error_mark_node || arglist == error_mark_node)
5765 return error_mark_node;
5767 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
5768 gcc_assert (fns && (is_overloaded_fn (fns)
5769 || TREE_CODE (fns) == IDENTIFIER_NODE));
5771 if (BASELINK_P (fns))
5773 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
5775 BASELINK_FUNCTIONS (fns),
5780 type = TREE_TYPE (fns);
5781 if (TREE_CODE (fns) == OVERLOAD || !type)
5782 type = unknown_type_node;
5784 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
5787 /* Within the scope of a template class S<T>, the name S gets bound
5788 (in build_self_reference) to a TYPE_DECL for the class, not a
5789 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
5790 or one of its enclosing classes, and that type is a template,
5791 return the associated TEMPLATE_DECL. Otherwise, the original
5792 DECL is returned. */
5795 maybe_get_template_decl_from_type_decl (tree decl)
5797 return (decl != NULL_TREE
5798 && TREE_CODE (decl) == TYPE_DECL
5799 && DECL_ARTIFICIAL (decl)
5800 && CLASS_TYPE_P (TREE_TYPE (decl))
5801 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
5802 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
5805 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
5806 parameters, find the desired type.
5808 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
5810 IN_DECL, if non-NULL, is the template declaration we are trying to
5813 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
5814 the class we are looking up.
5816 Issue error and warning messages under control of COMPLAIN.
5818 If the template class is really a local class in a template
5819 function, then the FUNCTION_CONTEXT is the function in which it is
5822 ??? Note that this function is currently called *twice* for each
5823 template-id: the first time from the parser, while creating the
5824 incomplete type (finish_template_type), and the second type during the
5825 real instantiation (instantiate_template_class). This is surely something
5826 that we want to avoid. It also causes some problems with argument
5827 coercion (see convert_nontype_argument for more information on this). */
5830 lookup_template_class (tree d1,
5835 tsubst_flags_t complain)
5837 tree templ = NULL_TREE, parmlist;
5844 timevar_push (TV_NAME_LOOKUP);
5846 if (TREE_CODE (d1) == IDENTIFIER_NODE)
5848 tree value = innermost_non_namespace_value (d1);
5849 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
5854 push_decl_namespace (context);
5855 templ = lookup_name (d1);
5856 templ = maybe_get_template_decl_from_type_decl (templ);
5858 pop_decl_namespace ();
5861 context = DECL_CONTEXT (templ);
5863 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
5865 tree type = TREE_TYPE (d1);
5867 /* If we are declaring a constructor, say A<T>::A<T>, we will get
5868 an implicit typename for the second A. Deal with it. */
5869 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
5870 type = TREE_TYPE (type);
5872 if (CLASSTYPE_TEMPLATE_INFO (type))
5874 templ = CLASSTYPE_TI_TEMPLATE (type);
5875 d1 = DECL_NAME (templ);
5878 else if (TREE_CODE (d1) == ENUMERAL_TYPE
5879 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
5881 templ = TYPE_TI_TEMPLATE (d1);
5882 d1 = DECL_NAME (templ);
5884 else if (TREE_CODE (d1) == TEMPLATE_DECL
5885 && DECL_TEMPLATE_RESULT (d1)
5886 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
5889 d1 = DECL_NAME (templ);
5890 context = DECL_CONTEXT (templ);
5893 /* Issue an error message if we didn't find a template. */
5896 if (complain & tf_error)
5897 error ("%qT is not a template", d1);
5898 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5901 if (TREE_CODE (templ) != TEMPLATE_DECL
5902 /* Make sure it's a user visible template, if it was named by
5904 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
5905 && !PRIMARY_TEMPLATE_P (templ)))
5907 if (complain & tf_error)
5909 error ("non-template type %qT used as a template", d1);
5911 error ("for template declaration %q+D", in_decl);
5913 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5916 complain &= ~tf_user;
5918 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
5920 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
5921 template arguments */
5927 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
5929 /* Consider an example where a template template parameter declared as
5931 template <class T, class U = std::allocator<T> > class TT
5933 The template parameter level of T and U are one level larger than
5934 of TT. To proper process the default argument of U, say when an
5935 instantiation `TT<int>' is seen, we need to build the full
5936 arguments containing {int} as the innermost level. Outer levels,
5937 available when not appearing as default template argument, can be
5938 obtained from the arguments of the enclosing template.
5940 Suppose that TT is later substituted with std::vector. The above
5941 instantiation is `TT<int, std::allocator<T> >' with TT at
5942 level 1, and T at level 2, while the template arguments at level 1
5943 becomes {std::vector} and the inner level 2 is {int}. */
5945 outer = DECL_CONTEXT (templ);
5947 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
5948 else if (current_template_parms)
5949 /* This is an argument of the current template, so we haven't set
5950 DECL_CONTEXT yet. */
5951 outer = current_template_args ();
5954 arglist = add_to_template_args (outer, arglist);
5956 arglist2 = coerce_template_parms (parmlist, arglist, templ,
5958 /*require_all_args=*/true,
5959 /*use_default_args=*/true);
5960 if (arglist2 == error_mark_node
5961 || (!uses_template_parms (arglist2)
5962 && check_instantiated_args (templ, arglist2, complain)))
5963 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5965 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
5966 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
5970 tree template_type = TREE_TYPE (templ);
5973 tree found = NULL_TREE;
5976 int is_partial_instantiation;
5978 gen_tmpl = most_general_template (templ);
5979 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
5980 parm_depth = TMPL_PARMS_DEPTH (parmlist);
5981 arg_depth = TMPL_ARGS_DEPTH (arglist);
5983 if (arg_depth == 1 && parm_depth > 1)
5985 /* We've been given an incomplete set of template arguments.
5988 template <class T> struct S1 {
5989 template <class U> struct S2 {};
5990 template <class U> struct S2<U*> {};
5993 we will be called with an ARGLIST of `U*', but the
5994 TEMPLATE will be `template <class T> template
5995 <class U> struct S1<T>::S2'. We must fill in the missing
5998 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
6000 arg_depth = TMPL_ARGS_DEPTH (arglist);
6003 /* Now we should have enough arguments. */
6004 gcc_assert (parm_depth == arg_depth);
6006 /* From here on, we're only interested in the most general
6009 /* Calculate the BOUND_ARGS. These will be the args that are
6010 actually tsubst'd into the definition to create the
6014 /* We have multiple levels of arguments to coerce, at once. */
6016 int saved_depth = TMPL_ARGS_DEPTH (arglist);
6018 tree bound_args = make_tree_vec (parm_depth);
6020 for (i = saved_depth,
6021 t = DECL_TEMPLATE_PARMS (gen_tmpl);
6022 i > 0 && t != NULL_TREE;
6023 --i, t = TREE_CHAIN (t))
6025 tree a = coerce_template_parms (TREE_VALUE (t),
6028 /*require_all_args=*/true,
6029 /*use_default_args=*/true);
6031 /* Don't process further if one of the levels fails. */
6032 if (a == error_mark_node)
6034 /* Restore the ARGLIST to its full size. */
6035 TREE_VEC_LENGTH (arglist) = saved_depth;
6036 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6039 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
6041 /* We temporarily reduce the length of the ARGLIST so
6042 that coerce_template_parms will see only the arguments
6043 corresponding to the template parameters it is
6045 TREE_VEC_LENGTH (arglist)--;
6048 /* Restore the ARGLIST to its full size. */
6049 TREE_VEC_LENGTH (arglist) = saved_depth;
6051 arglist = bound_args;
6055 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
6056 INNERMOST_TEMPLATE_ARGS (arglist),
6059 /*require_all_args=*/true,
6060 /*use_default_args=*/true);
6062 if (arglist == error_mark_node)
6063 /* We were unable to bind the arguments. */
6064 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6066 /* In the scope of a template class, explicit references to the
6067 template class refer to the type of the template, not any
6068 instantiation of it. For example, in:
6070 template <class T> class C { void f(C<T>); }
6072 the `C<T>' is just the same as `C'. Outside of the
6073 class, however, such a reference is an instantiation. */
6075 || !PRIMARY_TEMPLATE_P (gen_tmpl)
6076 || currently_open_class (template_type))
6077 /* comp_template_args is expensive, check it last. */
6078 && comp_template_args (TYPE_TI_ARGS (template_type),
6080 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, template_type);
6082 /* If we already have this specialization, return it. */
6083 elt.tmpl = gen_tmpl;
6085 hash = hash_specialization (&elt);
6086 entry = (spec_entry *) htab_find_with_hash (type_specializations,
6090 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, entry->spec);
6092 /* This type is a "partial instantiation" if any of the template
6093 arguments still involve template parameters. Note that we set
6094 IS_PARTIAL_INSTANTIATION for partial specializations as
6096 is_partial_instantiation = uses_template_parms (arglist);
6098 /* If the deduced arguments are invalid, then the binding
6100 if (!is_partial_instantiation
6101 && check_instantiated_args (gen_tmpl,
6102 INNERMOST_TEMPLATE_ARGS (arglist),
6104 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6106 if (!is_partial_instantiation
6107 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6108 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
6110 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
6111 DECL_NAME (gen_tmpl),
6112 /*tag_scope=*/ts_global);
6113 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
6116 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
6119 context = global_namespace;
6121 /* Create the type. */
6122 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
6124 if (!is_partial_instantiation)
6126 set_current_access_from_decl (TYPE_NAME (template_type));
6127 t = start_enum (TYPE_IDENTIFIER (template_type),
6128 tsubst (ENUM_UNDERLYING_TYPE (template_type),
6129 arglist, complain, in_decl),
6130 SCOPED_ENUM_P (template_type));
6134 /* We don't want to call start_enum for this type, since
6135 the values for the enumeration constants may involve
6136 template parameters. And, no one should be interested
6137 in the enumeration constants for such a type. */
6138 t = make_node (ENUMERAL_TYPE);
6139 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
6144 t = make_class_type (TREE_CODE (template_type));
6145 CLASSTYPE_DECLARED_CLASS (t)
6146 = CLASSTYPE_DECLARED_CLASS (template_type);
6147 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
6148 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
6150 /* A local class. Make sure the decl gets registered properly. */
6151 if (context == current_function_decl)
6152 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
6154 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
6155 /* This instantiation is another name for the primary
6156 template type. Set the TYPE_CANONICAL field
6158 TYPE_CANONICAL (t) = template_type;
6159 else if (any_template_arguments_need_structural_equality_p (arglist))
6160 /* Some of the template arguments require structural
6161 equality testing, so this template class requires
6162 structural equality testing. */
6163 SET_TYPE_STRUCTURAL_EQUALITY (t);
6166 /* If we called start_enum or pushtag above, this information
6167 will already be set up. */
6170 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
6172 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
6173 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
6174 TYPE_STUB_DECL (t) = type_decl;
6175 DECL_SOURCE_LOCATION (type_decl)
6176 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
6179 type_decl = TYPE_NAME (t);
6181 TREE_PRIVATE (type_decl)
6182 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
6183 TREE_PROTECTED (type_decl)
6184 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
6185 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
6187 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
6188 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
6191 /* Set up the template information. We have to figure out which
6192 template is the immediate parent if this is a full
6194 if (parm_depth == 1 || is_partial_instantiation
6195 || !PRIMARY_TEMPLATE_P (gen_tmpl))
6196 /* This case is easy; there are no member templates involved. */
6200 /* This is a full instantiation of a member template. Find
6201 the partial instantiation of which this is an instance. */
6203 /* Temporarily reduce by one the number of levels in the ARGLIST
6204 so as to avoid comparing the last set of arguments. */
6205 TREE_VEC_LENGTH (arglist)--;
6206 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
6207 TREE_VEC_LENGTH (arglist)++;
6208 found = CLASSTYPE_TI_TEMPLATE (found);
6211 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
6214 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
6215 &elt, hash, INSERT);
6216 *slot = GGC_NEW (spec_entry);
6219 /* Note this use of the partial instantiation so we can check it
6220 later in maybe_process_partial_specialization. */
6221 DECL_TEMPLATE_INSTANTIATIONS (templ)
6222 = tree_cons (arglist, t,
6223 DECL_TEMPLATE_INSTANTIATIONS (templ));
6225 if (TREE_CODE (t) == ENUMERAL_TYPE
6226 && !is_partial_instantiation)
6227 /* Now that the type has been registered on the instantiations
6228 list, we set up the enumerators. Because the enumeration
6229 constants may involve the enumeration type itself, we make
6230 sure to register the type first, and then create the
6231 constants. That way, doing tsubst_expr for the enumeration
6232 constants won't result in recursive calls here; we'll find
6233 the instantiation and exit above. */
6234 tsubst_enum (template_type, t, arglist);
6236 if (is_partial_instantiation)
6237 /* If the type makes use of template parameters, the
6238 code that generates debugging information will crash. */
6239 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
6241 /* Possibly limit visibility based on template args. */
6242 TREE_PUBLIC (type_decl) = 1;
6243 determine_visibility (type_decl);
6245 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
6247 timevar_pop (TV_NAME_LOOKUP);
6254 /* True when we should also visit template parameters that occur in
6255 non-deduced contexts. */
6256 bool include_nondeduced_p;
6257 struct pointer_set_t *visited;
6260 /* Called from for_each_template_parm via walk_tree. */
6263 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
6266 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
6267 tree_fn_t fn = pfd->fn;
6268 void *data = pfd->data;
6271 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
6272 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
6273 pfd->include_nondeduced_p))
6274 return error_mark_node;
6276 switch (TREE_CODE (t))
6279 if (TYPE_PTRMEMFUNC_P (t))
6285 if (!TYPE_TEMPLATE_INFO (t))
6287 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
6288 fn, data, pfd->visited,
6289 pfd->include_nondeduced_p))
6290 return error_mark_node;
6294 if (for_each_template_parm (TYPE_MIN_VALUE (t),
6295 fn, data, pfd->visited,
6296 pfd->include_nondeduced_p)
6297 || for_each_template_parm (TYPE_MAX_VALUE (t),
6298 fn, data, pfd->visited,
6299 pfd->include_nondeduced_p))
6300 return error_mark_node;
6304 /* Since we're not going to walk subtrees, we have to do this
6306 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
6307 pfd->visited, pfd->include_nondeduced_p))
6308 return error_mark_node;
6312 /* Check the return type. */
6313 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6314 pfd->include_nondeduced_p))
6315 return error_mark_node;
6317 /* Check the parameter types. Since default arguments are not
6318 instantiated until they are needed, the TYPE_ARG_TYPES may
6319 contain expressions that involve template parameters. But,
6320 no-one should be looking at them yet. And, once they're
6321 instantiated, they don't contain template parameters, so
6322 there's no point in looking at them then, either. */
6326 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
6327 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
6328 pfd->visited, pfd->include_nondeduced_p))
6329 return error_mark_node;
6331 /* Since we've already handled the TYPE_ARG_TYPES, we don't
6332 want walk_tree walking into them itself. */
6338 if (pfd->include_nondeduced_p
6339 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
6341 pfd->include_nondeduced_p))
6342 return error_mark_node;
6347 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
6348 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
6349 pfd->visited, pfd->include_nondeduced_p))
6350 return error_mark_node;
6355 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
6356 && for_each_template_parm (DECL_INITIAL (t), fn, data,
6357 pfd->visited, pfd->include_nondeduced_p))
6358 return error_mark_node;
6359 if (DECL_CONTEXT (t)
6360 && pfd->include_nondeduced_p
6361 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
6362 pfd->visited, pfd->include_nondeduced_p))
6363 return error_mark_node;
6366 case BOUND_TEMPLATE_TEMPLATE_PARM:
6367 /* Record template parameters such as `T' inside `TT<T>'. */
6368 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
6369 pfd->include_nondeduced_p))
6370 return error_mark_node;
6373 case TEMPLATE_TEMPLATE_PARM:
6374 case TEMPLATE_TYPE_PARM:
6375 case TEMPLATE_PARM_INDEX:
6376 if (fn && (*fn)(t, data))
6377 return error_mark_node;
6379 return error_mark_node;
6383 /* A template template parameter is encountered. */
6384 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
6385 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6386 pfd->include_nondeduced_p))
6387 return error_mark_node;
6389 /* Already substituted template template parameter */
6395 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
6397 pfd->include_nondeduced_p))
6398 return error_mark_node;
6402 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
6403 && pfd->include_nondeduced_p
6404 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
6405 (TREE_TYPE (t)), fn, data,
6406 pfd->visited, pfd->include_nondeduced_p))
6407 return error_mark_node;
6412 /* If there's no type, then this thing must be some expression
6413 involving template parameters. */
6414 if (!fn && !TREE_TYPE (t))
6415 return error_mark_node;
6420 case REINTERPRET_CAST_EXPR:
6421 case CONST_CAST_EXPR:
6422 case STATIC_CAST_EXPR:
6423 case DYNAMIC_CAST_EXPR:
6427 case PSEUDO_DTOR_EXPR:
6429 return error_mark_node;
6436 /* We didn't find any template parameters we liked. */
6440 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
6441 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
6442 call FN with the parameter and the DATA.
6443 If FN returns nonzero, the iteration is terminated, and
6444 for_each_template_parm returns 1. Otherwise, the iteration
6445 continues. If FN never returns a nonzero value, the value
6446 returned by for_each_template_parm is 0. If FN is NULL, it is
6447 considered to be the function which always returns 1.
6449 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
6450 parameters that occur in non-deduced contexts. When false, only
6451 visits those template parameters that can be deduced. */
6454 for_each_template_parm (tree t, tree_fn_t fn, void* data,
6455 struct pointer_set_t *visited,
6456 bool include_nondeduced_p)
6458 struct pair_fn_data pfd;
6464 pfd.include_nondeduced_p = include_nondeduced_p;
6466 /* Walk the tree. (Conceptually, we would like to walk without
6467 duplicates, but for_each_template_parm_r recursively calls
6468 for_each_template_parm, so we would need to reorganize a fair
6469 bit to use walk_tree_without_duplicates, so we keep our own
6472 pfd.visited = visited;
6474 pfd.visited = pointer_set_create ();
6475 result = cp_walk_tree (&t,
6476 for_each_template_parm_r,
6478 pfd.visited) != NULL_TREE;
6483 pointer_set_destroy (pfd.visited);
6490 /* Returns true if T depends on any template parameter. */
6493 uses_template_parms (tree t)
6496 int saved_processing_template_decl;
6498 saved_processing_template_decl = processing_template_decl;
6499 if (!saved_processing_template_decl)
6500 processing_template_decl = 1;
6502 dependent_p = dependent_type_p (t);
6503 else if (TREE_CODE (t) == TREE_VEC)
6504 dependent_p = any_dependent_template_arguments_p (t);
6505 else if (TREE_CODE (t) == TREE_LIST)
6506 dependent_p = (uses_template_parms (TREE_VALUE (t))
6507 || uses_template_parms (TREE_CHAIN (t)));
6508 else if (TREE_CODE (t) == TYPE_DECL)
6509 dependent_p = dependent_type_p (TREE_TYPE (t));
6512 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
6513 || TREE_CODE (t) == OVERLOAD
6514 || TREE_CODE (t) == BASELINK
6515 || TREE_CODE (t) == IDENTIFIER_NODE
6516 || TREE_CODE (t) == TRAIT_EXPR
6517 || TREE_CODE (t) == CONSTRUCTOR
6518 || CONSTANT_CLASS_P (t))
6519 dependent_p = (type_dependent_expression_p (t)
6520 || value_dependent_expression_p (t));
6523 gcc_assert (t == error_mark_node);
6524 dependent_p = false;
6527 processing_template_decl = saved_processing_template_decl;
6532 /* Returns true if T depends on any template parameter with level LEVEL. */
6535 uses_template_parms_level (tree t, int level)
6537 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
6538 /*include_nondeduced_p=*/true);
6541 static int tinst_depth;
6542 extern int max_tinst_depth;
6543 #ifdef GATHER_STATISTICS
6546 static int tinst_level_tick;
6547 static int last_template_error_tick;
6549 /* We're starting to instantiate D; record the template instantiation context
6550 for diagnostics and to restore it later. */
6553 push_tinst_level (tree d)
6555 struct tinst_level *new_level;
6557 if (tinst_depth >= max_tinst_depth)
6559 /* If the instantiation in question still has unbound template parms,
6560 we don't really care if we can't instantiate it, so just return.
6561 This happens with base instantiation for implicit `typename'. */
6562 if (uses_template_parms (d))
6565 last_template_error_tick = tinst_level_tick;
6566 error ("template instantiation depth exceeds maximum of %d (use "
6567 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
6568 max_tinst_depth, d);
6570 print_instantiation_context ();
6575 new_level = GGC_NEW (struct tinst_level);
6576 new_level->decl = d;
6577 new_level->locus = input_location;
6578 new_level->in_system_header_p = in_system_header;
6579 new_level->next = current_tinst_level;
6580 current_tinst_level = new_level;
6583 #ifdef GATHER_STATISTICS
6584 if (tinst_depth > depth_reached)
6585 depth_reached = tinst_depth;
6592 /* We're done instantiating this template; return to the instantiation
6596 pop_tinst_level (void)
6598 /* Restore the filename and line number stashed away when we started
6599 this instantiation. */
6600 input_location = current_tinst_level->locus;
6601 current_tinst_level = current_tinst_level->next;
6606 /* We're instantiating a deferred template; restore the template
6607 instantiation context in which the instantiation was requested, which
6608 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
6611 reopen_tinst_level (struct tinst_level *level)
6613 struct tinst_level *t;
6616 for (t = level; t; t = t->next)
6619 current_tinst_level = level;
6624 /* Returns the TINST_LEVEL which gives the original instantiation
6627 struct tinst_level *
6628 outermost_tinst_level (void)
6630 struct tinst_level *level = current_tinst_level;
6633 level = level->next;
6637 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
6640 parameter_of_template_p (tree parm, tree templ)
6645 if (!parm || !templ)
6648 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
6649 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
6651 parms = DECL_TEMPLATE_PARMS (templ);
6652 parms = INNERMOST_TEMPLATE_PARMS (parms);
6654 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
6655 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
6661 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
6662 vector of template arguments, as for tsubst.
6664 Returns an appropriate tsubst'd friend declaration. */
6667 tsubst_friend_function (tree decl, tree args)
6671 if (TREE_CODE (decl) == FUNCTION_DECL
6672 && DECL_TEMPLATE_INSTANTIATION (decl)
6673 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
6674 /* This was a friend declared with an explicit template
6675 argument list, e.g.:
6679 to indicate that f was a template instantiation, not a new
6680 function declaration. Now, we have to figure out what
6681 instantiation of what template. */
6683 tree template_id, arglist, fns;
6686 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
6688 /* Friend functions are looked up in the containing namespace scope.
6689 We must enter that scope, to avoid finding member functions of the
6690 current class with same name. */
6691 push_nested_namespace (ns);
6692 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
6693 tf_warning_or_error, NULL_TREE,
6694 /*integral_constant_expression_p=*/false);
6695 pop_nested_namespace (ns);
6696 arglist = tsubst (DECL_TI_ARGS (decl), args,
6697 tf_warning_or_error, NULL_TREE);
6698 template_id = lookup_template_function (fns, arglist);
6700 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6701 tmpl = determine_specialization (template_id, new_friend,
6703 /*need_member_template=*/0,
6704 TREE_VEC_LENGTH (args),
6706 return instantiate_template (tmpl, new_args, tf_error);
6709 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6711 /* The NEW_FRIEND will look like an instantiation, to the
6712 compiler, but is not an instantiation from the point of view of
6713 the language. For example, we might have had:
6715 template <class T> struct S {
6716 template <class U> friend void f(T, U);
6719 Then, in S<int>, template <class U> void f(int, U) is not an
6720 instantiation of anything. */
6721 if (new_friend == error_mark_node)
6722 return error_mark_node;
6724 DECL_USE_TEMPLATE (new_friend) = 0;
6725 if (TREE_CODE (decl) == TEMPLATE_DECL)
6727 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
6728 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
6729 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
6732 /* The mangled name for the NEW_FRIEND is incorrect. The function
6733 is not a template instantiation and should not be mangled like
6734 one. Therefore, we forget the mangling here; we'll recompute it
6735 later if we need it. */
6736 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
6738 SET_DECL_RTL (new_friend, NULL_RTX);
6739 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
6742 if (DECL_NAMESPACE_SCOPE_P (new_friend))
6745 tree new_friend_template_info;
6746 tree new_friend_result_template_info;
6748 int new_friend_is_defn;
6750 /* We must save some information from NEW_FRIEND before calling
6751 duplicate decls since that function will free NEW_FRIEND if
6753 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
6754 new_friend_is_defn =
6755 (DECL_INITIAL (DECL_TEMPLATE_RESULT
6756 (template_for_substitution (new_friend)))
6758 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
6760 /* This declaration is a `primary' template. */
6761 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
6763 new_friend_result_template_info
6764 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
6767 new_friend_result_template_info = NULL_TREE;
6769 /* Make the init_value nonzero so pushdecl knows this is a defn. */
6770 if (new_friend_is_defn)
6771 DECL_INITIAL (new_friend) = error_mark_node;
6773 /* Inside pushdecl_namespace_level, we will push into the
6774 current namespace. However, the friend function should go
6775 into the namespace of the template. */
6776 ns = decl_namespace_context (new_friend);
6777 push_nested_namespace (ns);
6778 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
6779 pop_nested_namespace (ns);
6781 if (old_decl == error_mark_node)
6782 return error_mark_node;
6784 if (old_decl != new_friend)
6786 /* This new friend declaration matched an existing
6787 declaration. For example, given:
6789 template <class T> void f(T);
6790 template <class U> class C {
6791 template <class T> friend void f(T) {}
6794 the friend declaration actually provides the definition
6795 of `f', once C has been instantiated for some type. So,
6796 old_decl will be the out-of-class template declaration,
6797 while new_friend is the in-class definition.
6799 But, if `f' was called before this point, the
6800 instantiation of `f' will have DECL_TI_ARGS corresponding
6801 to `T' but not to `U', references to which might appear
6802 in the definition of `f'. Previously, the most general
6803 template for an instantiation of `f' was the out-of-class
6804 version; now it is the in-class version. Therefore, we
6805 run through all specialization of `f', adding to their
6806 DECL_TI_ARGS appropriately. In particular, they need a
6807 new set of outer arguments, corresponding to the
6808 arguments for this class instantiation.
6810 The same situation can arise with something like this:
6813 template <class T> class C {
6817 when `C<int>' is instantiated. Now, `f(int)' is defined
6820 if (!new_friend_is_defn)
6821 /* On the other hand, if the in-class declaration does
6822 *not* provide a definition, then we don't want to alter
6823 existing definitions. We can just leave everything
6828 tree new_template = TI_TEMPLATE (new_friend_template_info);
6829 tree new_args = TI_ARGS (new_friend_template_info);
6831 /* Overwrite whatever template info was there before, if
6832 any, with the new template information pertaining to
6834 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
6836 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
6837 /* We should have called reregister_specialization in
6839 gcc_assert (retrieve_specialization (new_template,
6846 /* Indicate that the old function template is a partial
6848 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
6849 = new_friend_result_template_info;
6851 gcc_assert (new_template
6852 == most_general_template (new_template));
6853 gcc_assert (new_template != old_decl);
6855 /* Reassign any specializations already in the hash table
6856 to the new more general template, and add the
6857 additional template args. */
6858 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
6862 tree spec = TREE_VALUE (t);
6865 elt.tmpl = old_decl;
6866 elt.args = DECL_TI_ARGS (spec);
6867 elt.spec = NULL_TREE;
6869 htab_remove_elt (decl_specializations, &elt);
6872 = add_outermost_template_args (new_args,
6873 DECL_TI_ARGS (spec));
6875 register_specialization
6876 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
6879 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
6883 /* The information from NEW_FRIEND has been merged into OLD_DECL
6884 by duplicate_decls. */
6885 new_friend = old_decl;
6890 tree context = DECL_CONTEXT (new_friend);
6894 template <class T> class C {
6895 template <class U> friend void C1<U>::f (); // case 1
6896 friend void C2<T>::f (); // case 2
6898 we only need to make sure CONTEXT is a complete type for
6899 case 2. To distinguish between the two cases, we note that
6900 CONTEXT of case 1 remains dependent type after tsubst while
6901 this isn't true for case 2. */
6902 ++processing_template_decl;
6903 dependent_p = dependent_type_p (context);
6904 --processing_template_decl;
6907 && !complete_type_or_else (context, NULL_TREE))
6908 return error_mark_node;
6910 if (COMPLETE_TYPE_P (context))
6912 /* Check to see that the declaration is really present, and,
6913 possibly obtain an improved declaration. */
6914 tree fn = check_classfn (context,
6915 new_friend, NULL_TREE);
6925 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
6926 template arguments, as for tsubst.
6928 Returns an appropriate tsubst'd friend type or error_mark_node on
6932 tsubst_friend_class (tree friend_tmpl, tree args)
6938 context = DECL_CONTEXT (friend_tmpl);
6942 if (TREE_CODE (context) == NAMESPACE_DECL)
6943 push_nested_namespace (context);
6945 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
6948 /* Look for a class template declaration. We look for hidden names
6949 because two friend declarations of the same template are the
6950 same. For example, in:
6953 template <typename> friend class F;
6955 template <typename> struct B {
6956 template <typename> friend class F;
6959 both F templates are the same. */
6960 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
6961 /*block_p=*/true, 0,
6962 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
6964 /* But, if we don't find one, it might be because we're in a
6965 situation like this:
6973 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
6974 for `S<int>', not the TEMPLATE_DECL. */
6975 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
6977 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
6978 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
6981 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
6983 /* The friend template has already been declared. Just
6984 check to see that the declarations match, and install any new
6985 default parameters. We must tsubst the default parameters,
6986 of course. We only need the innermost template parameters
6987 because that is all that redeclare_class_template will look
6989 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
6990 > TMPL_ARGS_DEPTH (args))
6993 location_t saved_input_location;
6994 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
6995 args, tf_warning_or_error);
6997 saved_input_location = input_location;
6998 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
6999 redeclare_class_template (TREE_TYPE (tmpl), parms);
7000 input_location = saved_input_location;
7004 friend_type = TREE_TYPE (tmpl);
7008 /* The friend template has not already been declared. In this
7009 case, the instantiation of the template class will cause the
7010 injection of this template into the global scope. */
7011 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7012 if (tmpl == error_mark_node)
7013 return error_mark_node;
7015 /* The new TMPL is not an instantiation of anything, so we
7016 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7017 the new type because that is supposed to be the corresponding
7018 template decl, i.e., TMPL. */
7019 DECL_USE_TEMPLATE (tmpl) = 0;
7020 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7021 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7022 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7023 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7025 /* Inject this template into the global scope. */
7026 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7031 if (TREE_CODE (context) == NAMESPACE_DECL)
7032 pop_nested_namespace (context);
7034 pop_nested_class ();
7040 /* Returns zero if TYPE cannot be completed later due to circularity.
7041 Otherwise returns one. */
7044 can_complete_type_without_circularity (tree type)
7046 if (type == NULL_TREE || type == error_mark_node)
7048 else if (COMPLETE_TYPE_P (type))
7050 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7051 return can_complete_type_without_circularity (TREE_TYPE (type));
7052 else if (CLASS_TYPE_P (type)
7053 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
7059 /* Apply any attributes which had to be deferred until instantiation
7060 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
7061 ARGS, COMPLAIN, IN_DECL are as tsubst. */
7064 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
7065 tree args, tsubst_flags_t complain, tree in_decl)
7067 tree last_dep = NULL_TREE;
7071 for (t = attributes; t; t = TREE_CHAIN (t))
7072 if (ATTR_IS_DEPENDENT (t))
7075 attributes = copy_list (attributes);
7079 if (DECL_P (*decl_p))
7081 if (TREE_TYPE (*decl_p) == error_mark_node)
7083 p = &DECL_ATTRIBUTES (*decl_p);
7086 p = &TYPE_ATTRIBUTES (*decl_p);
7090 tree late_attrs = NULL_TREE;
7091 tree *q = &late_attrs;
7093 for (*p = attributes; *p; )
7096 if (ATTR_IS_DEPENDENT (t))
7098 *p = TREE_CHAIN (t);
7099 TREE_CHAIN (t) = NULL_TREE;
7100 /* If the first attribute argument is an identifier, don't
7101 pass it through tsubst. Attributes like mode, format,
7102 cleanup and several target specific attributes expect it
7105 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
7106 && TREE_VALUE (TREE_VALUE (t))
7107 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
7108 == IDENTIFIER_NODE))
7111 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
7113 /*integral_constant_expression_p=*/false);
7114 if (chain != TREE_CHAIN (TREE_VALUE (t)))
7116 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
7121 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
7122 /*integral_constant_expression_p=*/false);
7124 q = &TREE_CHAIN (t);
7127 p = &TREE_CHAIN (t);
7130 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
7134 /* Perform (or defer) access check for typedefs that were referenced
7135 from within the template TMPL code.
7136 This is a subroutine of instantiate_template and instantiate_class_template.
7137 TMPL is the template to consider and TARGS is the list of arguments of
7141 perform_typedefs_access_check (tree tmpl, tree targs)
7146 || (!CLASS_TYPE_P (tmpl)
7147 && TREE_CODE (tmpl) != FUNCTION_DECL))
7150 for (t = get_types_needing_access_check (tmpl); t; t = TREE_CHAIN (t))
7152 tree type_decl = TREE_PURPOSE (t);
7153 tree type_scope = TREE_VALUE (t);
7155 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
7158 if (uses_template_parms (type_decl))
7159 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
7160 if (uses_template_parms (type_scope))
7161 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
7163 perform_or_defer_access_check (TYPE_BINFO (type_scope),
7164 type_decl, type_decl);
7169 instantiate_class_template (tree type)
7171 tree templ, args, pattern, t, member;
7176 if (type == error_mark_node)
7177 return error_mark_node;
7179 if (TYPE_BEING_DEFINED (type)
7180 || COMPLETE_TYPE_P (type)
7181 || dependent_type_p (type))
7184 /* Figure out which template is being instantiated. */
7185 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
7186 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7188 /* Determine what specialization of the original template to
7190 t = most_specialized_class (type, templ);
7191 if (t == error_mark_node)
7193 TYPE_BEING_DEFINED (type) = 1;
7194 return error_mark_node;
7198 /* This TYPE is actually an instantiation of a partial
7199 specialization. We replace the innermost set of ARGS with
7200 the arguments appropriate for substitution. For example,
7203 template <class T> struct S {};
7204 template <class T> struct S<T*> {};
7206 and supposing that we are instantiating S<int*>, ARGS will
7207 presently be {int*} -- but we need {int}. */
7208 pattern = TREE_TYPE (t);
7209 args = TREE_PURPOSE (t);
7213 pattern = TREE_TYPE (templ);
7214 args = CLASSTYPE_TI_ARGS (type);
7217 /* If the template we're instantiating is incomplete, then clearly
7218 there's nothing we can do. */
7219 if (!COMPLETE_TYPE_P (pattern))
7222 /* If we've recursively instantiated too many templates, stop. */
7223 if (! push_tinst_level (type))
7226 /* Now we're really doing the instantiation. Mark the type as in
7227 the process of being defined. */
7228 TYPE_BEING_DEFINED (type) = 1;
7230 /* We may be in the middle of deferred access check. Disable
7232 push_deferring_access_checks (dk_no_deferred);
7234 push_to_top_level ();
7236 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
7238 /* Set the input location to the most specialized template definition.
7239 This is needed if tsubsting causes an error. */
7240 typedecl = TYPE_MAIN_DECL (pattern);
7241 input_location = DECL_SOURCE_LOCATION (typedecl);
7243 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
7244 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
7245 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
7246 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
7247 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
7248 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
7249 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
7250 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
7251 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
7252 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
7253 TYPE_PACKED (type) = TYPE_PACKED (pattern);
7254 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
7255 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
7256 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
7257 if (ANON_AGGR_TYPE_P (pattern))
7258 SET_ANON_AGGR_TYPE_P (type);
7259 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
7261 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
7262 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
7265 pbinfo = TYPE_BINFO (pattern);
7267 /* We should never instantiate a nested class before its enclosing
7268 class; we need to look up the nested class by name before we can
7269 instantiate it, and that lookup should instantiate the enclosing
7271 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
7272 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
7273 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
7275 base_list = NULL_TREE;
7276 if (BINFO_N_BASE_BINFOS (pbinfo))
7279 tree context = TYPE_CONTEXT (type);
7283 /* We must enter the scope containing the type, as that is where
7284 the accessibility of types named in dependent bases are
7286 pushed_scope = push_scope (context ? context : global_namespace);
7288 /* Substitute into each of the bases to determine the actual
7290 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
7293 tree access = BINFO_BASE_ACCESS (pbinfo, i);
7294 tree expanded_bases = NULL_TREE;
7297 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
7300 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
7301 args, tf_error, NULL_TREE);
7302 if (expanded_bases == error_mark_node)
7305 len = TREE_VEC_LENGTH (expanded_bases);
7308 for (idx = 0; idx < len; idx++)
7311 /* Extract the already-expanded base class. */
7312 base = TREE_VEC_ELT (expanded_bases, idx);
7314 /* Substitute to figure out the base class. */
7315 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
7318 if (base == error_mark_node)
7321 base_list = tree_cons (access, base, base_list);
7322 if (BINFO_VIRTUAL_P (pbase_binfo))
7323 TREE_TYPE (base_list) = integer_type_node;
7327 /* The list is now in reverse order; correct that. */
7328 base_list = nreverse (base_list);
7331 pop_scope (pushed_scope);
7333 /* Now call xref_basetypes to set up all the base-class
7335 xref_basetypes (type, base_list);
7337 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
7338 (int) ATTR_FLAG_TYPE_IN_PLACE,
7339 args, tf_error, NULL_TREE);
7341 /* Now that our base classes are set up, enter the scope of the
7342 class, so that name lookups into base classes, etc. will work
7343 correctly. This is precisely analogous to what we do in
7344 begin_class_definition when defining an ordinary non-template
7345 class, except we also need to push the enclosing classes. */
7346 push_nested_class (type);
7348 /* Now members are processed in the order of declaration. */
7349 for (member = CLASSTYPE_DECL_LIST (pattern);
7350 member; member = TREE_CHAIN (member))
7352 tree t = TREE_VALUE (member);
7354 if (TREE_PURPOSE (member))
7358 /* Build new CLASSTYPE_NESTED_UTDS. */
7361 bool class_template_p;
7363 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
7364 && TYPE_LANG_SPECIFIC (t)
7365 && CLASSTYPE_IS_TEMPLATE (t));
7366 /* If the member is a class template, then -- even after
7367 substitution -- there may be dependent types in the
7368 template argument list for the class. We increment
7369 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
7370 that function will assume that no types are dependent
7371 when outside of a template. */
7372 if (class_template_p)
7373 ++processing_template_decl;
7374 newtag = tsubst (t, args, tf_error, NULL_TREE);
7375 if (class_template_p)
7376 --processing_template_decl;
7377 if (newtag == error_mark_node)
7380 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
7382 tree name = TYPE_IDENTIFIER (t);
7384 if (class_template_p)
7385 /* Unfortunately, lookup_template_class sets
7386 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
7387 instantiation (i.e., for the type of a member
7388 template class nested within a template class.)
7389 This behavior is required for
7390 maybe_process_partial_specialization to work
7391 correctly, but is not accurate in this case;
7392 the TAG is not an instantiation of anything.
7393 (The corresponding TEMPLATE_DECL is an
7394 instantiation, but the TYPE is not.) */
7395 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
7397 /* Now, we call pushtag to put this NEWTAG into the scope of
7398 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
7399 pushtag calling push_template_decl. We don't have to do
7400 this for enums because it will already have been done in
7403 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
7404 pushtag (name, newtag, /*tag_scope=*/ts_current);
7407 else if (TREE_CODE (t) == FUNCTION_DECL
7408 || DECL_FUNCTION_TEMPLATE_P (t))
7410 /* Build new TYPE_METHODS. */
7413 if (TREE_CODE (t) == TEMPLATE_DECL)
7414 ++processing_template_decl;
7415 r = tsubst (t, args, tf_error, NULL_TREE);
7416 if (TREE_CODE (t) == TEMPLATE_DECL)
7417 --processing_template_decl;
7418 set_current_access_from_decl (r);
7419 finish_member_declaration (r);
7423 /* Build new TYPE_FIELDS. */
7424 if (TREE_CODE (t) == STATIC_ASSERT)
7427 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
7428 tf_warning_or_error, NULL_TREE,
7429 /*integral_constant_expression_p=*/true);
7430 finish_static_assert (condition,
7431 STATIC_ASSERT_MESSAGE (t),
7432 STATIC_ASSERT_SOURCE_LOCATION (t),
7435 else if (TREE_CODE (t) != CONST_DECL)
7439 /* The file and line for this declaration, to
7440 assist in error message reporting. Since we
7441 called push_tinst_level above, we don't need to
7443 input_location = DECL_SOURCE_LOCATION (t);
7445 if (TREE_CODE (t) == TEMPLATE_DECL)
7446 ++processing_template_decl;
7447 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
7448 if (TREE_CODE (t) == TEMPLATE_DECL)
7449 --processing_template_decl;
7450 if (TREE_CODE (r) == VAR_DECL)
7454 [t]he initialization (and any associated
7455 side-effects) of a static data member does
7456 not occur unless the static data member is
7457 itself used in a way that requires the
7458 definition of the static data member to
7461 Therefore, we do not substitute into the
7462 initialized for the static data member here. */
7463 finish_static_data_member_decl
7466 /*init_const_expr_p=*/false,
7467 /*asmspec_tree=*/NULL_TREE,
7469 if (DECL_INITIALIZED_IN_CLASS_P (r))
7470 check_static_variable_definition (r, TREE_TYPE (r));
7472 else if (TREE_CODE (r) == FIELD_DECL)
7474 /* Determine whether R has a valid type and can be
7475 completed later. If R is invalid, then it is
7476 replaced by error_mark_node so that it will not be
7477 added to TYPE_FIELDS. */
7478 tree rtype = TREE_TYPE (r);
7479 if (can_complete_type_without_circularity (rtype))
7480 complete_type (rtype);
7482 if (!COMPLETE_TYPE_P (rtype))
7484 cxx_incomplete_type_error (r, rtype);
7485 r = error_mark_node;
7489 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
7490 such a thing will already have been added to the field
7491 list by tsubst_enum in finish_member_declaration in the
7492 CLASSTYPE_NESTED_UTDS case above. */
7493 if (!(TREE_CODE (r) == TYPE_DECL
7494 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
7495 && DECL_ARTIFICIAL (r)))
7497 set_current_access_from_decl (r);
7498 finish_member_declaration (r);
7505 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
7507 /* Build new CLASSTYPE_FRIEND_CLASSES. */
7509 tree friend_type = t;
7510 bool adjust_processing_template_decl = false;
7512 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7514 /* template <class T> friend class C; */
7515 friend_type = tsubst_friend_class (friend_type, args);
7516 adjust_processing_template_decl = true;
7518 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
7520 /* template <class T> friend class C::D; */
7521 friend_type = tsubst (friend_type, args,
7522 tf_warning_or_error, NULL_TREE);
7523 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7524 friend_type = TREE_TYPE (friend_type);
7525 adjust_processing_template_decl = true;
7527 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
7529 /* This could be either
7533 when dependent_type_p is false or
7535 template <class U> friend class T::C;
7538 friend_type = tsubst (friend_type, args,
7539 tf_warning_or_error, NULL_TREE);
7540 /* Bump processing_template_decl for correct
7541 dependent_type_p calculation. */
7542 ++processing_template_decl;
7543 if (dependent_type_p (friend_type))
7544 adjust_processing_template_decl = true;
7545 --processing_template_decl;
7547 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
7548 && hidden_name_p (TYPE_NAME (friend_type)))
7552 where C hasn't been declared yet. Let's lookup name
7553 from namespace scope directly, bypassing any name that
7554 come from dependent base class. */
7555 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
7557 /* The call to xref_tag_from_type does injection for friend
7559 push_nested_namespace (ns);
7561 xref_tag_from_type (friend_type, NULL_TREE,
7562 /*tag_scope=*/ts_current);
7563 pop_nested_namespace (ns);
7565 else if (uses_template_parms (friend_type))
7566 /* friend class C<T>; */
7567 friend_type = tsubst (friend_type, args,
7568 tf_warning_or_error, NULL_TREE);
7573 where C is already declared or
7575 friend class C<int>;
7577 We don't have to do anything in these cases. */
7579 if (adjust_processing_template_decl)
7580 /* Trick make_friend_class into realizing that the friend
7581 we're adding is a template, not an ordinary class. It's
7582 important that we use make_friend_class since it will
7583 perform some error-checking and output cross-reference
7585 ++processing_template_decl;
7587 if (friend_type != error_mark_node)
7588 make_friend_class (type, friend_type, /*complain=*/false);
7590 if (adjust_processing_template_decl)
7591 --processing_template_decl;
7595 /* Build new DECL_FRIENDLIST. */
7598 /* The file and line for this declaration, to
7599 assist in error message reporting. Since we
7600 called push_tinst_level above, we don't need to
7602 input_location = DECL_SOURCE_LOCATION (t);
7604 if (TREE_CODE (t) == TEMPLATE_DECL)
7606 ++processing_template_decl;
7607 push_deferring_access_checks (dk_no_check);
7610 r = tsubst_friend_function (t, args);
7611 add_friend (type, r, /*complain=*/false);
7612 if (TREE_CODE (t) == TEMPLATE_DECL)
7614 pop_deferring_access_checks ();
7615 --processing_template_decl;
7621 /* Set the file and line number information to whatever is given for
7622 the class itself. This puts error messages involving generated
7623 implicit functions at a predictable point, and the same point
7624 that would be used for non-template classes. */
7625 input_location = DECL_SOURCE_LOCATION (typedecl);
7627 unreverse_member_declarations (type);
7628 finish_struct_1 (type);
7629 TYPE_BEING_DEFINED (type) = 0;
7631 /* Now that the class is complete, instantiate default arguments for
7632 any member functions. We don't do this earlier because the
7633 default arguments may reference members of the class. */
7634 if (!PRIMARY_TEMPLATE_P (templ))
7635 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
7636 if (TREE_CODE (t) == FUNCTION_DECL
7637 /* Implicitly generated member functions will not have template
7638 information; they are not instantiations, but instead are
7639 created "fresh" for each instantiation. */
7640 && DECL_TEMPLATE_INFO (t))
7641 tsubst_default_arguments (t);
7643 /* Some typedefs referenced from within the template code need to be access
7644 checked at template instantiation time, i.e now. These types were
7645 added to the template at parsing time. Let's get those and perform
7646 the access checks then. */
7647 perform_typedefs_access_check (pattern, args);
7648 perform_deferred_access_checks ();
7649 pop_nested_class ();
7650 pop_from_top_level ();
7651 pop_deferring_access_checks ();
7654 /* The vtable for a template class can be emitted in any translation
7655 unit in which the class is instantiated. When there is no key
7656 method, however, finish_struct_1 will already have added TYPE to
7657 the keyed_classes list. */
7658 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
7659 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
7665 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7671 else if (TYPE_P (t))
7672 r = tsubst (t, args, complain, in_decl);
7675 r = tsubst_expr (t, args, complain, in_decl,
7676 /*integral_constant_expression_p=*/true);
7677 r = fold_non_dependent_expr (r);
7682 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
7683 NONTYPE_ARGUMENT_PACK. */
7686 make_fnparm_pack (tree spec_parm)
7688 /* Collect all of the extra "packed" parameters into an
7692 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
7693 tree argtypepack = make_node (TYPE_ARGUMENT_PACK);
7694 int i, len = list_length (spec_parm);
7696 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
7697 parmvec = make_tree_vec (len);
7698 parmtypevec = make_tree_vec (len);
7699 for (i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
7701 TREE_VEC_ELT (parmvec, i) = spec_parm;
7702 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
7705 /* Build the argument packs. */
7706 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
7707 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
7708 TREE_TYPE (argpack) = argtypepack;
7713 /* Substitute ARGS into T, which is an pack expansion
7714 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
7715 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
7716 (if only a partial substitution could be performed) or
7717 ERROR_MARK_NODE if there was an error. */
7719 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
7723 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
7724 tree first_arg_pack; int i, len = -1;
7727 bool very_local_specializations = false;
7729 gcc_assert (PACK_EXPANSION_P (t));
7730 pattern = PACK_EXPANSION_PATTERN (t);
7732 /* Determine the argument packs that will instantiate the parameter
7733 packs used in the expansion expression. While we're at it,
7734 compute the number of arguments to be expanded and make sure it
7736 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
7737 pack = TREE_CHAIN (pack))
7739 tree parm_pack = TREE_VALUE (pack);
7740 tree arg_pack = NULL_TREE;
7741 tree orig_arg = NULL_TREE;
7743 if (TREE_CODE (parm_pack) == PARM_DECL)
7745 arg_pack = retrieve_local_specialization (parm_pack);
7746 if (arg_pack == NULL_TREE)
7748 /* This can happen for a parameter name used later in a function
7749 declaration (such as in a late-specified return type). Just
7750 make a dummy decl, since it's only used for its type. */
7751 gcc_assert (cp_unevaluated_operand != 0);
7752 arg_pack = tsubst_decl (parm_pack, args, complain);
7753 arg_pack = make_fnparm_pack (arg_pack);
7758 int level, idx, levels;
7759 template_parm_level_and_index (parm_pack, &level, &idx);
7761 levels = TMPL_ARGS_DEPTH (args);
7762 if (level <= levels)
7763 arg_pack = TMPL_ARG (args, level, idx);
7766 orig_arg = arg_pack;
7767 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
7768 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
7770 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
7771 /* This can only happen if we forget to expand an argument
7772 pack somewhere else. Just return an error, silently. */
7774 result = make_tree_vec (1);
7775 TREE_VEC_ELT (result, 0) = error_mark_node;
7780 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
7781 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
7783 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
7784 tree pattern = PACK_EXPANSION_PATTERN (expansion);
7785 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
7786 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
7787 /* The argument pack that the parameter maps to is just an
7788 expansion of the parameter itself, such as one would
7789 find in the implicit typedef of a class inside the
7790 class itself. Consider this parameter "unsubstituted",
7791 so that we will maintain the outer pack expansion. */
7792 arg_pack = NULL_TREE;
7798 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
7800 /* It's all-or-nothing with incomplete argument packs. */
7801 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7802 return error_mark_node;
7804 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7810 first_arg_pack = arg_pack;
7812 else if (len != my_len)
7814 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
7815 error ("mismatched argument pack lengths while expanding "
7819 error ("mismatched argument pack lengths while expanding "
7822 return error_mark_node;
7825 /* Keep track of the parameter packs and their corresponding
7827 packs = tree_cons (parm_pack, arg_pack, packs);
7828 TREE_TYPE (packs) = orig_arg;
7831 /* We can't substitute for this parameter pack. */
7832 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
7834 unsubstituted_packs);
7837 /* We cannot expand this expansion expression, because we don't have
7838 all of the argument packs we need. Substitute into the pattern
7839 and return a PACK_EXPANSION_*. The caller will need to deal with
7841 if (unsubstituted_packs)
7844 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
7845 new_pat = tsubst_expr (pattern, args, complain, in_decl,
7846 /*integral_constant_expression_p=*/false);
7848 new_pat = tsubst (pattern, args, complain, in_decl);
7849 return make_pack_expansion (new_pat);
7852 /* We could not find any argument packs that work. */
7854 return error_mark_node;
7856 if (!local_specializations)
7858 /* We're in a late-specified return type, so we don't have a local
7859 specializations table. Create one for doing this expansion. */
7860 very_local_specializations = true;
7861 local_specializations = htab_create (37,
7862 hash_local_specialization,
7863 eq_local_specializations,
7867 /* For each argument in each argument pack, substitute into the
7869 result = make_tree_vec (len + incomplete);
7870 for (i = 0; i < len + incomplete; ++i)
7872 /* For parameter pack, change the substitution of the parameter
7873 pack to the ith argument in its argument pack, then expand
7875 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7877 tree parm = TREE_PURPOSE (pack);
7879 if (TREE_CODE (parm) == PARM_DECL)
7881 /* Select the Ith argument from the pack. */
7882 tree arg = make_node (ARGUMENT_PACK_SELECT);
7883 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
7884 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
7886 register_local_specialization (arg, parm);
7892 template_parm_level_and_index (parm, &level, &idx);
7896 /* Select the Ith argument from the pack. */
7897 value = make_node (ARGUMENT_PACK_SELECT);
7898 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
7899 ARGUMENT_PACK_SELECT_INDEX (value) = i;
7902 /* Update the corresponding argument. */
7903 TMPL_ARG (args, level, idx) = value;
7907 /* Substitute into the PATTERN with the altered arguments. */
7908 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
7909 TREE_VEC_ELT (result, i) =
7910 tsubst_expr (pattern, args, complain, in_decl,
7911 /*integral_constant_expression_p=*/false);
7913 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
7916 /* When we have incomplete argument packs, the last "expanded"
7917 result is itself a pack expansion, which allows us
7918 to deduce more arguments. */
7919 TREE_VEC_ELT (result, i) =
7920 make_pack_expansion (TREE_VEC_ELT (result, i));
7922 if (TREE_VEC_ELT (result, i) == error_mark_node)
7924 result = error_mark_node;
7929 /* Update ARGS to restore the substitution from parameter packs to
7930 their argument packs. */
7931 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7933 tree parm = TREE_PURPOSE (pack);
7935 if (TREE_CODE (parm) == PARM_DECL)
7936 register_local_specialization (TREE_TYPE (pack), parm);
7940 template_parm_level_and_index (parm, &level, &idx);
7942 /* Update the corresponding argument. */
7943 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
7944 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
7947 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
7951 if (very_local_specializations)
7953 htab_delete (local_specializations);
7954 local_specializations = NULL;
7960 /* Substitute ARGS into the vector or list of template arguments T. */
7963 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7966 int len = TREE_VEC_LENGTH (t);
7967 int need_new = 0, i, expanded_len_adjust = 0, out;
7968 tree *elts = (tree *) alloca (len * sizeof (tree));
7970 for (i = 0; i < len; i++)
7972 tree orig_arg = TREE_VEC_ELT (t, i);
7975 if (TREE_CODE (orig_arg) == TREE_VEC)
7976 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
7977 else if (PACK_EXPANSION_P (orig_arg))
7979 /* Substitute into an expansion expression. */
7980 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
7982 if (TREE_CODE (new_arg) == TREE_VEC)
7983 /* Add to the expanded length adjustment the number of
7984 expanded arguments. We subtract one from this
7985 measurement, because the argument pack expression
7986 itself is already counted as 1 in
7987 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
7988 the argument pack is empty. */
7989 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
7991 else if (ARGUMENT_PACK_P (orig_arg))
7993 /* Substitute into each of the arguments. */
7994 new_arg = make_node (TREE_CODE (orig_arg));
7996 SET_ARGUMENT_PACK_ARGS (
7998 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
7999 args, complain, in_decl));
8001 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
8002 new_arg = error_mark_node;
8004 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
8005 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
8007 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
8009 if (TREE_TYPE (new_arg) == error_mark_node)
8010 new_arg = error_mark_node;
8014 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
8016 if (new_arg == error_mark_node)
8017 return error_mark_node;
8020 if (new_arg != orig_arg)
8027 /* Make space for the expanded arguments coming from template
8029 t = make_tree_vec (len + expanded_len_adjust);
8030 for (i = 0, out = 0; i < len; i++)
8032 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
8033 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
8034 && TREE_CODE (elts[i]) == TREE_VEC)
8038 /* Now expand the template argument pack "in place". */
8039 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
8040 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
8044 TREE_VEC_ELT (t, out) = elts[i];
8052 /* Return the result of substituting ARGS into the template parameters
8053 given by PARMS. If there are m levels of ARGS and m + n levels of
8054 PARMS, then the result will contain n levels of PARMS. For
8055 example, if PARMS is `template <class T> template <class U>
8056 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
8057 result will be `template <int*, double, class V>'. */
8060 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
8065 /* When substituting into a template, we must set
8066 PROCESSING_TEMPLATE_DECL as the template parameters may be
8067 dependent if they are based on one-another, and the dependency
8068 predicates are short-circuit outside of templates. */
8069 ++processing_template_decl;
8071 for (new_parms = &r;
8072 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
8073 new_parms = &(TREE_CHAIN (*new_parms)),
8074 parms = TREE_CHAIN (parms))
8077 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
8080 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
8086 if (parms == error_mark_node)
8089 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
8091 if (tuple == error_mark_node)
8094 default_value = TREE_PURPOSE (tuple);
8095 parm_decl = TREE_VALUE (tuple);
8097 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
8098 if (TREE_CODE (parm_decl) == PARM_DECL
8099 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
8100 parm_decl = error_mark_node;
8101 default_value = tsubst_template_arg (default_value, args,
8102 complain, NULL_TREE);
8104 tuple = build_tree_list (default_value, parm_decl);
8105 TREE_VEC_ELT (new_vec, i) = tuple;
8109 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
8110 - TMPL_ARGS_DEPTH (args)),
8111 new_vec, NULL_TREE);
8114 --processing_template_decl;
8119 /* Substitute the ARGS into the indicated aggregate (or enumeration)
8120 type T. If T is not an aggregate or enumeration type, it is
8121 handled as if by tsubst. IN_DECL is as for tsubst. If
8122 ENTERING_SCOPE is nonzero, T is the context for a template which
8123 we are presently tsubst'ing. Return the substituted value. */
8126 tsubst_aggr_type (tree t,
8128 tsubst_flags_t complain,
8135 switch (TREE_CODE (t))
8138 if (TYPE_PTRMEMFUNC_P (t))
8139 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
8141 /* Else fall through. */
8144 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
8149 int saved_unevaluated_operand;
8150 int saved_inhibit_evaluation_warnings;
8152 /* In "sizeof(X<I>)" we need to evaluate "I". */
8153 saved_unevaluated_operand = cp_unevaluated_operand;
8154 cp_unevaluated_operand = 0;
8155 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
8156 c_inhibit_evaluation_warnings = 0;
8158 /* First, determine the context for the type we are looking
8160 context = TYPE_CONTEXT (t);
8163 context = tsubst_aggr_type (context, args, complain,
8164 in_decl, /*entering_scope=*/1);
8165 /* If context is a nested class inside a class template,
8166 it may still need to be instantiated (c++/33959). */
8167 if (TYPE_P (context))
8168 context = complete_type (context);
8171 /* Then, figure out what arguments are appropriate for the
8172 type we are trying to find. For example, given:
8174 template <class T> struct S;
8175 template <class T, class U> void f(T, U) { S<U> su; }
8177 and supposing that we are instantiating f<int, double>,
8178 then our ARGS will be {int, double}, but, when looking up
8179 S we only want {double}. */
8180 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
8182 if (argvec == error_mark_node)
8183 r = error_mark_node;
8186 r = lookup_template_class (t, argvec, in_decl, context,
8187 entering_scope, complain);
8188 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
8191 cp_unevaluated_operand = saved_unevaluated_operand;
8192 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
8197 /* This is not a template type, so there's nothing to do. */
8201 return tsubst (t, args, complain, in_decl);
8205 /* Substitute into the default argument ARG (a default argument for
8206 FN), which has the indicated TYPE. */
8209 tsubst_default_argument (tree fn, tree type, tree arg)
8211 tree saved_class_ptr = NULL_TREE;
8212 tree saved_class_ref = NULL_TREE;
8214 /* This default argument came from a template. Instantiate the
8215 default argument here, not in tsubst. In the case of
8224 we must be careful to do name lookup in the scope of S<T>,
8225 rather than in the current class. */
8226 push_access_scope (fn);
8227 /* The "this" pointer is not valid in a default argument. */
8230 saved_class_ptr = current_class_ptr;
8231 cp_function_chain->x_current_class_ptr = NULL_TREE;
8232 saved_class_ref = current_class_ref;
8233 cp_function_chain->x_current_class_ref = NULL_TREE;
8236 push_deferring_access_checks(dk_no_deferred);
8237 /* The default argument expression may cause implicitly defined
8238 member functions to be synthesized, which will result in garbage
8239 collection. We must treat this situation as if we were within
8240 the body of function so as to avoid collecting live data on the
8243 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
8244 tf_warning_or_error, NULL_TREE,
8245 /*integral_constant_expression_p=*/false);
8247 pop_deferring_access_checks();
8249 /* Restore the "this" pointer. */
8252 cp_function_chain->x_current_class_ptr = saved_class_ptr;
8253 cp_function_chain->x_current_class_ref = saved_class_ref;
8256 /* Make sure the default argument is reasonable. */
8257 arg = check_default_argument (type, arg);
8259 pop_access_scope (fn);
8264 /* Substitute into all the default arguments for FN. */
8267 tsubst_default_arguments (tree fn)
8272 tmpl_args = DECL_TI_ARGS (fn);
8274 /* If this function is not yet instantiated, we certainly don't need
8275 its default arguments. */
8276 if (uses_template_parms (tmpl_args))
8279 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
8281 arg = TREE_CHAIN (arg))
8282 if (TREE_PURPOSE (arg))
8283 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
8285 TREE_PURPOSE (arg));
8288 /* Substitute the ARGS into the T, which is a _DECL. Return the
8289 result of the substitution. Issue error and warning messages under
8290 control of COMPLAIN. */
8293 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
8295 location_t saved_loc;
8300 /* Set the filename and linenumber to improve error-reporting. */
8301 saved_loc = input_location;
8302 input_location = DECL_SOURCE_LOCATION (t);
8304 switch (TREE_CODE (t))
8308 /* We can get here when processing a member function template,
8309 member class template, or template template parameter. */
8310 tree decl = DECL_TEMPLATE_RESULT (t);
8315 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
8317 /* Template template parameter is treated here. */
8318 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8319 if (new_type == error_mark_node)
8320 return error_mark_node;
8323 TREE_CHAIN (r) = NULL_TREE;
8324 TREE_TYPE (r) = new_type;
8325 DECL_TEMPLATE_RESULT (r)
8326 = build_decl (DECL_SOURCE_LOCATION (decl),
8327 TYPE_DECL, DECL_NAME (decl), new_type);
8328 DECL_TEMPLATE_PARMS (r)
8329 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8331 TYPE_NAME (new_type) = r;
8335 /* We might already have an instance of this template.
8336 The ARGS are for the surrounding class type, so the
8337 full args contain the tsubst'd args for the context,
8338 plus the innermost args from the template decl. */
8339 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
8340 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
8341 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
8342 /* Because this is a template, the arguments will still be
8343 dependent, even after substitution. If
8344 PROCESSING_TEMPLATE_DECL is not set, the dependency
8345 predicates will short-circuit. */
8346 ++processing_template_decl;
8347 full_args = tsubst_template_args (tmpl_args, args,
8349 --processing_template_decl;
8350 if (full_args == error_mark_node)
8351 return error_mark_node;
8353 /* If this is a default template template argument,
8354 tsubst might not have changed anything. */
8355 if (full_args == tmpl_args)
8358 hash = hash_tmpl_and_args (t, full_args);
8359 spec = retrieve_specialization (t, full_args, hash);
8360 if (spec != NULL_TREE)
8366 /* Make a new template decl. It will be similar to the
8367 original, but will record the current template arguments.
8368 We also create a new function declaration, which is just
8369 like the old one, but points to this new template, rather
8370 than the old one. */
8372 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
8373 TREE_CHAIN (r) = NULL_TREE;
8375 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
8377 if (TREE_CODE (decl) == TYPE_DECL)
8380 ++processing_template_decl;
8381 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8382 --processing_template_decl;
8383 if (new_type == error_mark_node)
8384 return error_mark_node;
8386 TREE_TYPE (r) = new_type;
8387 CLASSTYPE_TI_TEMPLATE (new_type) = r;
8388 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
8389 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
8390 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
8395 ++processing_template_decl;
8396 new_decl = tsubst (decl, args, complain, in_decl);
8397 --processing_template_decl;
8398 if (new_decl == error_mark_node)
8399 return error_mark_node;
8401 DECL_TEMPLATE_RESULT (r) = new_decl;
8402 DECL_TI_TEMPLATE (new_decl) = r;
8403 TREE_TYPE (r) = TREE_TYPE (new_decl);
8404 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
8405 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
8408 SET_DECL_IMPLICIT_INSTANTIATION (r);
8409 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
8410 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
8412 /* The template parameters for this new template are all the
8413 template parameters for the old template, except the
8414 outermost level of parameters. */
8415 DECL_TEMPLATE_PARMS (r)
8416 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8419 if (PRIMARY_TEMPLATE_P (t))
8420 DECL_PRIMARY_TEMPLATE (r) = r;
8422 if (TREE_CODE (decl) != TYPE_DECL)
8423 /* Record this non-type partial instantiation. */
8424 register_specialization (r, t,
8425 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
8433 tree argvec = NULL_TREE;
8441 /* Nobody should be tsubst'ing into non-template functions. */
8442 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
8444 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
8449 /* If T is not dependent, just return it. We have to
8450 increment PROCESSING_TEMPLATE_DECL because
8451 value_dependent_expression_p assumes that nothing is
8452 dependent when PROCESSING_TEMPLATE_DECL is zero. */
8453 ++processing_template_decl;
8454 dependent_p = value_dependent_expression_p (t);
8455 --processing_template_decl;
8459 /* Calculate the most general template of which R is a
8460 specialization, and the complete set of arguments used to
8462 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
8463 argvec = tsubst_template_args (DECL_TI_ARGS
8464 (DECL_TEMPLATE_RESULT (gen_tmpl)),
8465 args, complain, in_decl);
8467 /* Check to see if we already have this specialization. */
8468 hash = hash_tmpl_and_args (gen_tmpl, argvec);
8469 spec = retrieve_specialization (gen_tmpl, argvec, hash);
8477 /* We can see more levels of arguments than parameters if
8478 there was a specialization of a member template, like
8481 template <class T> struct S { template <class U> void f(); }
8482 template <> template <class U> void S<int>::f(U);
8484 Here, we'll be substituting into the specialization,
8485 because that's where we can find the code we actually
8486 want to generate, but we'll have enough arguments for
8487 the most general template.
8489 We also deal with the peculiar case:
8491 template <class T> struct S {
8492 template <class U> friend void f();
8494 template <class U> void f() {}
8496 template void f<double>();
8498 Here, the ARGS for the instantiation of will be {int,
8499 double}. But, we only need as many ARGS as there are
8500 levels of template parameters in CODE_PATTERN. We are
8501 careful not to get fooled into reducing the ARGS in
8504 template <class T> struct S { template <class U> void f(U); }
8505 template <class T> template <> void S<T>::f(int) {}
8507 which we can spot because the pattern will be a
8508 specialization in this case. */
8509 args_depth = TMPL_ARGS_DEPTH (args);
8511 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
8512 if (args_depth > parms_depth
8513 && !DECL_TEMPLATE_SPECIALIZATION (t))
8514 args = get_innermost_template_args (args, parms_depth);
8518 /* This special case arises when we have something like this:
8520 template <class T> struct S {
8521 friend void f<int>(int, double);
8524 Here, the DECL_TI_TEMPLATE for the friend declaration
8525 will be an IDENTIFIER_NODE. We are being called from
8526 tsubst_friend_function, and we want only to create a
8527 new decl (R) with appropriate types so that we can call
8528 determine_specialization. */
8529 gen_tmpl = NULL_TREE;
8532 if (DECL_CLASS_SCOPE_P (t))
8534 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
8538 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
8539 complain, t, /*entering_scope=*/1);
8544 ctx = DECL_CONTEXT (t);
8546 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8547 if (type == error_mark_node)
8548 return error_mark_node;
8550 /* We do NOT check for matching decls pushed separately at this
8551 point, as they may not represent instantiations of this
8552 template, and in any case are considered separate under the
8555 DECL_USE_TEMPLATE (r) = 0;
8556 TREE_TYPE (r) = type;
8557 /* Clear out the mangled name and RTL for the instantiation. */
8558 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8559 SET_DECL_RTL (r, NULL_RTX);
8560 /* Leave DECL_INITIAL set on deleted instantiations. */
8561 if (!DECL_DELETED_FN (r))
8562 DECL_INITIAL (r) = NULL_TREE;
8563 DECL_CONTEXT (r) = ctx;
8565 if (member && DECL_CONV_FN_P (r))
8566 /* Type-conversion operator. Reconstruct the name, in
8567 case it's the name of one of the template's parameters. */
8568 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
8570 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
8572 DECL_RESULT (r) = NULL_TREE;
8574 TREE_STATIC (r) = 0;
8575 TREE_PUBLIC (r) = TREE_PUBLIC (t);
8576 DECL_EXTERNAL (r) = 1;
8577 /* If this is an instantiation of a function with internal
8578 linkage, we already know what object file linkage will be
8579 assigned to the instantiation. */
8580 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
8581 DECL_DEFER_OUTPUT (r) = 0;
8582 TREE_CHAIN (r) = NULL_TREE;
8583 DECL_PENDING_INLINE_INFO (r) = 0;
8584 DECL_PENDING_INLINE_P (r) = 0;
8585 DECL_SAVED_TREE (r) = NULL_TREE;
8586 DECL_STRUCT_FUNCTION (r) = NULL;
8588 /* We'll re-clone as appropriate in instantiate_template. */
8589 DECL_CLONED_FUNCTION (r) = NULL_TREE;
8591 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
8592 this in the special friend case mentioned above where
8593 GEN_TMPL is NULL. */
8596 DECL_TEMPLATE_INFO (r)
8597 = tree_cons (gen_tmpl, argvec, NULL_TREE);
8598 SET_DECL_IMPLICIT_INSTANTIATION (r);
8599 register_specialization (r, gen_tmpl, argvec, false, hash);
8601 /* We're not supposed to instantiate default arguments
8602 until they are called, for a template. But, for a
8605 template <class T> void f ()
8606 { extern void g(int i = T()); }
8608 we should do the substitution when the template is
8609 instantiated. We handle the member function case in
8610 instantiate_class_template since the default arguments
8611 might refer to other members of the class. */
8613 && !PRIMARY_TEMPLATE_P (gen_tmpl)
8614 && !uses_template_parms (argvec))
8615 tsubst_default_arguments (r);
8618 DECL_TEMPLATE_INFO (r) = NULL_TREE;
8620 /* Copy the list of befriending classes. */
8621 for (friends = &DECL_BEFRIENDING_CLASSES (r);
8623 friends = &TREE_CHAIN (*friends))
8625 *friends = copy_node (*friends);
8626 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
8631 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
8633 maybe_retrofit_in_chrg (r);
8634 if (DECL_CONSTRUCTOR_P (r))
8635 grok_ctor_properties (ctx, r);
8636 /* If this is an instantiation of a member template, clone it.
8637 If it isn't, that'll be handled by
8638 clone_constructors_and_destructors. */
8639 if (PRIMARY_TEMPLATE_P (gen_tmpl))
8640 clone_function_decl (r, /*update_method_vec_p=*/0);
8642 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r))
8643 && !grok_op_properties (r, (complain & tf_error) != 0))
8644 return error_mark_node;
8646 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
8647 SET_DECL_FRIEND_CONTEXT (r,
8648 tsubst (DECL_FRIEND_CONTEXT (t),
8649 args, complain, in_decl));
8651 /* Possibly limit visibility based on template args. */
8652 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8653 if (DECL_VISIBILITY_SPECIFIED (t))
8655 DECL_VISIBILITY_SPECIFIED (r) = 0;
8657 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8659 determine_visibility (r);
8661 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8662 args, complain, in_decl);
8668 tree type = NULL_TREE;
8670 tree expanded_types = NULL_TREE;
8671 tree prev_r = NULL_TREE;
8672 tree first_r = NULL_TREE;
8674 if (FUNCTION_PARAMETER_PACK_P (t))
8676 /* If there is a local specialization that isn't a
8677 parameter pack, it means that we're doing a "simple"
8678 substitution from inside tsubst_pack_expansion. Just
8679 return the local specialization (which will be a single
8681 tree spec = retrieve_local_specialization (t);
8683 && TREE_CODE (spec) == PARM_DECL
8684 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
8687 /* Expand the TYPE_PACK_EXPANSION that provides the types for
8688 the parameters in this function parameter pack. */
8689 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
8691 if (TREE_CODE (expanded_types) == TREE_VEC)
8693 len = TREE_VEC_LENGTH (expanded_types);
8695 /* Zero-length parameter packs are boring. Just substitute
8698 return tsubst (TREE_CHAIN (t), args, complain,
8703 /* All we did was update the type. Make a note of that. */
8704 type = expanded_types;
8705 expanded_types = NULL_TREE;
8709 /* Loop through all of the parameter's we'll build. When T is
8710 a function parameter pack, LEN is the number of expanded
8711 types in EXPANDED_TYPES; otherwise, LEN is 1. */
8713 for (i = 0; i < len; ++i)
8717 if (DECL_TEMPLATE_PARM_P (t))
8718 SET_DECL_TEMPLATE_PARM_P (r);
8721 /* We're on the Ith parameter of the function parameter
8724 /* Get the Ith type. */
8725 type = TREE_VEC_ELT (expanded_types, i);
8728 /* Rename the parameter to include the index. */
8730 make_ith_pack_parameter_name (DECL_NAME (r), i);
8733 /* We're dealing with a normal parameter. */
8734 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8736 type = type_decays_to (type);
8737 TREE_TYPE (r) = type;
8738 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8740 if (DECL_INITIAL (r))
8742 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
8743 DECL_INITIAL (r) = TREE_TYPE (r);
8745 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
8749 DECL_CONTEXT (r) = NULL_TREE;
8751 if (!DECL_TEMPLATE_PARM_P (r))
8752 DECL_ARG_TYPE (r) = type_passed_as (type);
8754 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8755 args, complain, in_decl);
8757 /* Keep track of the first new parameter we
8758 generate. That's what will be returned to the
8763 /* Build a proper chain of parameters when substituting
8764 into a function parameter pack. */
8766 TREE_CHAIN (prev_r) = r;
8770 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
8771 complain, TREE_CHAIN (t));
8773 /* FIRST_R contains the start of the chain we've built. */
8783 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8784 if (type == error_mark_node)
8785 return error_mark_node;
8786 TREE_TYPE (r) = type;
8787 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8789 /* DECL_INITIAL gives the number of bits in a bit-field. */
8791 = tsubst_expr (DECL_INITIAL (t), args,
8793 /*integral_constant_expression_p=*/true);
8794 /* We don't have to set DECL_CONTEXT here; it is set by
8795 finish_member_declaration. */
8796 TREE_CHAIN (r) = NULL_TREE;
8797 if (VOID_TYPE_P (type))
8798 error ("instantiation of %q+D as type %qT", r, type);
8800 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8801 args, complain, in_decl);
8806 /* We reach here only for member using decls. */
8807 if (DECL_DEPENDENT_P (t))
8809 r = do_class_using_decl
8810 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
8811 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
8813 r = error_mark_node;
8816 TREE_PROTECTED (r) = TREE_PROTECTED (t);
8817 TREE_PRIVATE (r) = TREE_PRIVATE (t);
8823 TREE_CHAIN (r) = NULL_TREE;
8830 tree argvec = NULL_TREE;
8831 tree gen_tmpl = NULL_TREE;
8833 tree tmpl = NULL_TREE;
8835 tree type = NULL_TREE;
8838 if (TREE_CODE (t) == TYPE_DECL
8839 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
8841 /* If this is the canonical decl, we don't have to
8842 mess with instantiations, and often we can't (for
8843 typename, template type parms and such). Note that
8844 TYPE_NAME is not correct for the above test if
8845 we've copied the type for a typedef. */
8846 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8847 if (type == error_mark_node)
8848 return error_mark_node;
8849 r = TYPE_NAME (type);
8853 /* Check to see if we already have the specialization we
8856 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
8858 /* T is a static data member or namespace-scope entity.
8859 We have to substitute into namespace-scope variables
8860 (even though such entities are never templates) because
8863 template <class T> void f() { extern T t; }
8865 where the entity referenced is not known until
8866 instantiation time. */
8868 ctx = DECL_CONTEXT (t);
8869 if (DECL_CLASS_SCOPE_P (t))
8871 ctx = tsubst_aggr_type (ctx, args,
8873 in_decl, /*entering_scope=*/1);
8874 /* If CTX is unchanged, then T is in fact the
8875 specialization we want. That situation occurs when
8876 referencing a static data member within in its own
8877 class. We can use pointer equality, rather than
8878 same_type_p, because DECL_CONTEXT is always
8880 if (ctx == DECL_CONTEXT (t))
8886 tmpl = DECL_TI_TEMPLATE (t);
8887 gen_tmpl = most_general_template (tmpl);
8888 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
8889 hash = hash_tmpl_and_args (gen_tmpl, argvec);
8890 spec = retrieve_specialization (gen_tmpl, argvec, hash);
8895 /* A local variable. */
8897 /* Subsequent calls to pushdecl will fill this in. */
8899 spec = retrieve_local_specialization (t);
8901 /* If we already have the specialization we need, there is
8902 nothing more to do. */
8909 /* Create a new node for the specialization we need. */
8911 if (type == NULL_TREE)
8912 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8913 if (TREE_CODE (r) == VAR_DECL)
8915 /* Even if the original location is out of scope, the
8916 newly substituted one is not. */
8917 DECL_DEAD_FOR_LOCAL (r) = 0;
8918 DECL_INITIALIZED_P (r) = 0;
8919 DECL_TEMPLATE_INSTANTIATED (r) = 0;
8920 if (type == error_mark_node)
8921 return error_mark_node;
8922 if (TREE_CODE (type) == FUNCTION_TYPE)
8924 /* It may seem that this case cannot occur, since:
8929 declares a function, not a variable. However:
8932 template <typename T> void g() { T t; }
8933 template void g<f>();
8935 is an attempt to declare a variable with function
8937 error ("variable %qD has function type",
8938 /* R is not yet sufficiently initialized, so we
8939 just use its name. */
8941 return error_mark_node;
8943 type = complete_type (type);
8944 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
8945 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
8946 type = check_var_type (DECL_NAME (r), type);
8948 if (DECL_HAS_VALUE_EXPR_P (t))
8950 tree ve = DECL_VALUE_EXPR (t);
8951 ve = tsubst_expr (ve, args, complain, in_decl,
8952 /*constant_expression_p=*/false);
8953 SET_DECL_VALUE_EXPR (r, ve);
8956 else if (DECL_SELF_REFERENCE_P (t))
8957 SET_DECL_SELF_REFERENCE_P (r);
8958 TREE_TYPE (r) = type;
8959 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8960 DECL_CONTEXT (r) = ctx;
8961 /* Clear out the mangled name and RTL for the instantiation. */
8962 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8963 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8964 SET_DECL_RTL (r, NULL_RTX);
8965 /* The initializer must not be expanded until it is required;
8967 DECL_INITIAL (r) = NULL_TREE;
8968 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8969 SET_DECL_RTL (r, NULL_RTX);
8970 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
8971 if (TREE_CODE (r) == VAR_DECL)
8973 /* Possibly limit visibility based on template args. */
8974 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8975 if (DECL_VISIBILITY_SPECIFIED (t))
8977 DECL_VISIBILITY_SPECIFIED (r) = 0;
8979 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8981 determine_visibility (r);
8983 /* Preserve a typedef that names a type. */
8984 else if (TREE_CODE (r) == TYPE_DECL
8985 && DECL_ORIGINAL_TYPE (t)
8986 && type != error_mark_node)
8988 DECL_ORIGINAL_TYPE (r) = tsubst (DECL_ORIGINAL_TYPE (t),
8989 args, complain, in_decl);
8990 TREE_TYPE (r) = type = build_variant_type_copy (type);
8991 TYPE_NAME (type) = r;
8996 /* A static data member declaration is always marked
8997 external when it is declared in-class, even if an
8998 initializer is present. We mimic the non-template
9000 DECL_EXTERNAL (r) = 1;
9002 register_specialization (r, gen_tmpl, argvec, false, hash);
9003 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
9004 SET_DECL_IMPLICIT_INSTANTIATION (r);
9007 register_local_specialization (r, t);
9009 TREE_CHAIN (r) = NULL_TREE;
9011 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
9012 (int) ATTR_FLAG_TYPE_IN_PLACE,
9013 args, complain, in_decl);
9022 /* Restore the file and line information. */
9023 input_location = saved_loc;
9028 /* Substitute into the ARG_TYPES of a function type. */
9031 tsubst_arg_types (tree arg_types,
9033 tsubst_flags_t complain,
9036 tree remaining_arg_types;
9037 tree type = NULL_TREE;
9039 tree expanded_args = NULL_TREE;
9042 if (!arg_types || arg_types == void_list_node)
9045 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
9046 args, complain, in_decl);
9047 if (remaining_arg_types == error_mark_node)
9048 return error_mark_node;
9050 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
9052 /* For a pack expansion, perform substitution on the
9053 entire expression. Later on, we'll handle the arguments
9055 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
9056 args, complain, in_decl);
9058 if (TREE_CODE (expanded_args) == TREE_VEC)
9059 /* So that we'll spin through the parameters, one by one. */
9060 i = TREE_VEC_LENGTH (expanded_args);
9063 /* We only partially substituted into the parameter
9064 pack. Our type is TYPE_PACK_EXPANSION. */
9065 type = expanded_args;
9066 expanded_args = NULL_TREE;
9074 type = TREE_VEC_ELT (expanded_args, i);
9076 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
9078 if (type == error_mark_node)
9079 return error_mark_node;
9080 if (VOID_TYPE_P (type))
9082 if (complain & tf_error)
9084 error ("invalid parameter type %qT", type);
9086 error ("in declaration %q+D", in_decl);
9088 return error_mark_node;
9091 /* Do array-to-pointer, function-to-pointer conversion, and ignore
9092 top-level qualifiers as required. */
9093 type = TYPE_MAIN_VARIANT (type_decays_to (type));
9095 /* We do not substitute into default arguments here. The standard
9096 mandates that they be instantiated only when needed, which is
9097 done in build_over_call. */
9098 default_arg = TREE_PURPOSE (arg_types);
9100 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
9102 /* We've instantiated a template before its default arguments
9103 have been parsed. This can happen for a nested template
9104 class, and is not an error unless we require the default
9105 argument in a call of this function. */
9106 remaining_arg_types =
9107 tree_cons (default_arg, type, remaining_arg_types);
9108 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
9109 remaining_arg_types);
9112 remaining_arg_types =
9113 hash_tree_cons (default_arg, type, remaining_arg_types);
9116 return remaining_arg_types;
9119 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
9120 *not* handle the exception-specification for FNTYPE, because the
9121 initial substitution of explicitly provided template parameters
9122 during argument deduction forbids substitution into the
9123 exception-specification:
9127 All references in the function type of the function template to the
9128 corresponding template parameters are replaced by the specified tem-
9129 plate argument values. If a substitution in a template parameter or
9130 in the function type of the function template results in an invalid
9131 type, type deduction fails. [Note: The equivalent substitution in
9132 exception specifications is done only when the function is instanti-
9133 ated, at which point a program is ill-formed if the substitution
9134 results in an invalid type.] */
9137 tsubst_function_type (tree t,
9139 tsubst_flags_t complain,
9146 /* The TYPE_CONTEXT is not used for function/method types. */
9147 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
9149 /* Substitute the return type. */
9150 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9151 if (return_type == error_mark_node)
9152 return error_mark_node;
9153 /* The standard does not presently indicate that creation of a
9154 function type with an invalid return type is a deduction failure.
9155 However, that is clearly analogous to creating an array of "void"
9156 or a reference to a reference. This is core issue #486. */
9157 if (TREE_CODE (return_type) == ARRAY_TYPE
9158 || TREE_CODE (return_type) == FUNCTION_TYPE)
9160 if (complain & tf_error)
9162 if (TREE_CODE (return_type) == ARRAY_TYPE)
9163 error ("function returning an array");
9165 error ("function returning a function");
9167 return error_mark_node;
9170 /* Substitute the argument types. */
9171 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
9173 if (arg_types == error_mark_node)
9174 return error_mark_node;
9176 /* Construct a new type node and return it. */
9177 if (TREE_CODE (t) == FUNCTION_TYPE)
9178 fntype = build_function_type (return_type, arg_types);
9181 tree r = TREE_TYPE (TREE_VALUE (arg_types));
9182 if (! MAYBE_CLASS_TYPE_P (r))
9186 Type deduction may fail for any of the following
9189 -- Attempting to create "pointer to member of T" when T
9190 is not a class type. */
9191 if (complain & tf_error)
9192 error ("creating pointer to member function of non-class type %qT",
9194 return error_mark_node;
9197 fntype = build_method_type_directly (r, return_type,
9198 TREE_CHAIN (arg_types));
9200 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
9201 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
9206 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
9207 ARGS into that specification, and return the substituted
9208 specification. If there is no specification, return NULL_TREE. */
9211 tsubst_exception_specification (tree fntype,
9213 tsubst_flags_t complain,
9219 specs = TYPE_RAISES_EXCEPTIONS (fntype);
9220 new_specs = NULL_TREE;
9223 if (! TREE_VALUE (specs))
9230 tree expanded_specs = NULL_TREE;
9232 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
9234 /* Expand the pack expansion type. */
9235 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
9239 if (expanded_specs == error_mark_node)
9240 return error_mark_node;
9241 else if (TREE_CODE (expanded_specs) == TREE_VEC)
9242 len = TREE_VEC_LENGTH (expanded_specs);
9245 /* We're substituting into a member template, so
9246 we got a TYPE_PACK_EXPANSION back. Add that
9247 expansion and move on. */
9248 gcc_assert (TREE_CODE (expanded_specs)
9249 == TYPE_PACK_EXPANSION);
9250 new_specs = add_exception_specifier (new_specs,
9253 specs = TREE_CHAIN (specs);
9258 for (i = 0; i < len; ++i)
9261 spec = TREE_VEC_ELT (expanded_specs, i);
9263 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
9264 if (spec == error_mark_node)
9266 new_specs = add_exception_specifier (new_specs, spec,
9270 specs = TREE_CHAIN (specs);
9276 /* Take the tree structure T and replace template parameters used
9277 therein with the argument vector ARGS. IN_DECL is an associated
9278 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
9279 Issue error and warning messages under control of COMPLAIN. Note
9280 that we must be relatively non-tolerant of extensions here, in
9281 order to preserve conformance; if we allow substitutions that
9282 should not be allowed, we may allow argument deductions that should
9283 not succeed, and therefore report ambiguous overload situations
9284 where there are none. In theory, we could allow the substitution,
9285 but indicate that it should have failed, and allow our caller to
9286 make sure that the right thing happens, but we don't try to do this
9289 This function is used for dealing with types, decls and the like;
9290 for expressions, use tsubst_expr or tsubst_copy. */
9293 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9297 if (t == NULL_TREE || t == error_mark_node
9298 || t == integer_type_node
9299 || t == void_type_node
9300 || t == char_type_node
9301 || t == unknown_type_node
9302 || TREE_CODE (t) == NAMESPACE_DECL)
9306 return tsubst_decl (t, args, complain);
9308 if (args == NULL_TREE)
9311 if (TREE_CODE (t) == IDENTIFIER_NODE)
9312 type = IDENTIFIER_TYPE_VALUE (t);
9314 type = TREE_TYPE (t);
9316 gcc_assert (type != unknown_type_node);
9318 /* Reuse typedefs. We need to do this to handle dependent attributes,
9319 such as attribute aligned. */
9322 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
9324 tree decl = TYPE_NAME (t);
9326 if (DECL_CLASS_SCOPE_P (decl)
9327 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
9328 && uses_template_parms (DECL_CONTEXT (decl)))
9330 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
9331 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
9332 r = retrieve_specialization (tmpl, gen_args, 0);
9334 else if (DECL_FUNCTION_SCOPE_P (decl)
9335 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
9336 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
9337 r = retrieve_local_specialization (decl);
9339 /* The typedef is from a non-template context. */
9345 r = cp_build_qualified_type_real
9346 (r, cp_type_quals (t) | cp_type_quals (r),
9347 complain | tf_ignore_bad_quals);
9350 /* Else we must be instantiating the typedef, so fall through. */
9354 && TREE_CODE (t) != TYPENAME_TYPE
9355 && TREE_CODE (t) != IDENTIFIER_NODE
9356 && TREE_CODE (t) != FUNCTION_TYPE
9357 && TREE_CODE (t) != METHOD_TYPE)
9358 type = tsubst (type, args, complain, in_decl);
9359 if (type == error_mark_node)
9360 return error_mark_node;
9362 switch (TREE_CODE (t))
9367 return tsubst_aggr_type (t, args, complain, in_decl,
9368 /*entering_scope=*/0);
9371 case IDENTIFIER_NODE:
9383 if (t == integer_type_node)
9386 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
9387 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
9391 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
9393 max = tsubst_expr (omax, args, complain, in_decl,
9394 /*integral_constant_expression_p=*/false);
9396 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
9398 if (TREE_CODE (max) == NOP_EXPR
9399 && TREE_SIDE_EFFECTS (omax)
9400 && !TREE_TYPE (max))
9401 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
9403 max = fold_decl_constant_value (max);
9405 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
9406 with TREE_SIDE_EFFECTS that indicates this is not an integral
9407 constant expression. */
9408 if (processing_template_decl
9409 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
9411 gcc_assert (TREE_CODE (max) == NOP_EXPR);
9412 TREE_SIDE_EFFECTS (max) = 1;
9415 if (TREE_CODE (max) != INTEGER_CST
9416 && !at_function_scope_p ()
9417 && !TREE_SIDE_EFFECTS (max)
9418 && !value_dependent_expression_p (max))
9420 if (complain & tf_error)
9421 error ("array bound is not an integer constant");
9422 return error_mark_node;
9427 Type deduction may fail for any of the following
9430 Attempting to create an array with a size that is
9431 zero or negative. */
9432 if (integer_zerop (max) && !(complain & tf_error))
9433 /* We must fail if performing argument deduction (as
9434 indicated by the state of complain), so that
9435 another substitution can be found. */
9436 return error_mark_node;
9437 else if (TREE_CODE (max) == INTEGER_CST
9438 && INT_CST_LT (max, integer_zero_node))
9440 if (complain & tf_error)
9441 error ("creating array with negative size (%qE)", max);
9443 return error_mark_node;
9446 return compute_array_index_type (NULL_TREE, max);
9449 case TEMPLATE_TYPE_PARM:
9450 case TEMPLATE_TEMPLATE_PARM:
9451 case BOUND_TEMPLATE_TEMPLATE_PARM:
9452 case TEMPLATE_PARM_INDEX:
9457 tree arg = NULL_TREE;
9461 gcc_assert (TREE_VEC_LENGTH (args) > 0);
9462 template_parm_level_and_index (t, &level, &idx);
9464 levels = TMPL_ARGS_DEPTH (args);
9465 if (level <= levels)
9467 arg = TMPL_ARG (args, level, idx);
9469 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
9470 /* See through ARGUMENT_PACK_SELECT arguments. */
9471 arg = ARGUMENT_PACK_SELECT_ARG (arg);
9474 if (arg == error_mark_node)
9475 return error_mark_node;
9476 else if (arg != NULL_TREE)
9478 if (ARGUMENT_PACK_P (arg))
9479 /* If ARG is an argument pack, we don't actually want to
9480 perform a substitution here, because substitutions
9481 for argument packs are only done
9482 element-by-element. We can get to this point when
9483 substituting the type of a non-type template
9484 parameter pack, when that type actually contains
9485 template parameter packs from an outer template, e.g.,
9487 template<typename... Types> struct A {
9488 template<Types... Values> struct B { };
9492 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
9495 gcc_assert (TYPE_P (arg));
9497 /* cv-quals from the template are discarded when
9498 substituting in a function or reference type. */
9499 if (TREE_CODE (arg) == FUNCTION_TYPE
9500 || TREE_CODE (arg) == METHOD_TYPE
9501 || TREE_CODE (arg) == REFERENCE_TYPE)
9502 quals = cp_type_quals (arg);
9504 quals = cp_type_quals (arg) | cp_type_quals (t);
9506 return cp_build_qualified_type_real
9507 (arg, quals, complain | tf_ignore_bad_quals);
9509 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9511 /* We are processing a type constructed from a
9512 template template parameter. */
9513 tree argvec = tsubst (TYPE_TI_ARGS (t),
9514 args, complain, in_decl);
9515 if (argvec == error_mark_node)
9516 return error_mark_node;
9518 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
9519 are resolving nested-types in the signature of a
9520 member function templates. Otherwise ARG is a
9521 TEMPLATE_DECL and is the real template to be
9523 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
9524 arg = TYPE_NAME (arg);
9526 r = lookup_template_class (arg,
9529 /*entering_scope=*/0,
9531 return cp_build_qualified_type_real
9532 (r, TYPE_QUALS (t), complain);
9535 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
9540 /* This can happen during the attempted tsubst'ing in
9541 unify. This means that we don't yet have any information
9542 about the template parameter in question. */
9545 /* If we get here, we must have been looking at a parm for a
9546 more deeply nested template. Make a new version of this
9547 template parameter, but with a lower level. */
9548 switch (TREE_CODE (t))
9550 case TEMPLATE_TYPE_PARM:
9551 case TEMPLATE_TEMPLATE_PARM:
9552 case BOUND_TEMPLATE_TEMPLATE_PARM:
9553 if (cp_type_quals (t))
9555 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
9556 r = cp_build_qualified_type_real
9557 (r, cp_type_quals (t),
9558 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
9559 ? tf_ignore_bad_quals : 0));
9564 TEMPLATE_TYPE_PARM_INDEX (r)
9565 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
9566 r, levels, args, complain);
9567 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
9568 TYPE_MAIN_VARIANT (r) = r;
9569 TYPE_POINTER_TO (r) = NULL_TREE;
9570 TYPE_REFERENCE_TO (r) = NULL_TREE;
9572 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
9573 /* We have reduced the level of the template
9574 template parameter, but not the levels of its
9575 template parameters, so canonical_type_parameter
9576 will not be able to find the canonical template
9577 template parameter for this level. Thus, we
9578 require structural equality checking to compare
9579 TEMPLATE_TEMPLATE_PARMs. */
9580 SET_TYPE_STRUCTURAL_EQUALITY (r);
9581 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
9582 SET_TYPE_STRUCTURAL_EQUALITY (r);
9584 TYPE_CANONICAL (r) = canonical_type_parameter (r);
9586 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9588 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
9590 if (argvec == error_mark_node)
9591 return error_mark_node;
9593 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
9594 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
9599 case TEMPLATE_PARM_INDEX:
9600 r = reduce_template_parm_level (t, type, levels, args, complain);
9612 tree purpose, value, chain;
9614 if (t == void_list_node)
9617 purpose = TREE_PURPOSE (t);
9620 purpose = tsubst (purpose, args, complain, in_decl);
9621 if (purpose == error_mark_node)
9622 return error_mark_node;
9624 value = TREE_VALUE (t);
9627 value = tsubst (value, args, complain, in_decl);
9628 if (value == error_mark_node)
9629 return error_mark_node;
9631 chain = TREE_CHAIN (t);
9632 if (chain && chain != void_type_node)
9634 chain = tsubst (chain, args, complain, in_decl);
9635 if (chain == error_mark_node)
9636 return error_mark_node;
9638 if (purpose == TREE_PURPOSE (t)
9639 && value == TREE_VALUE (t)
9640 && chain == TREE_CHAIN (t))
9642 return hash_tree_cons (purpose, value, chain);
9646 /* We should never be tsubsting a binfo. */
9650 /* A vector of template arguments. */
9652 return tsubst_template_args (t, args, complain, in_decl);
9655 case REFERENCE_TYPE:
9657 enum tree_code code;
9659 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
9662 code = TREE_CODE (t);
9667 Type deduction may fail for any of the following
9670 -- Attempting to create a pointer to reference type.
9671 -- Attempting to create a reference to a reference type or
9672 a reference to void.
9674 Core issue 106 says that creating a reference to a reference
9675 during instantiation is no longer a cause for failure. We
9676 only enforce this check in strict C++98 mode. */
9677 if ((TREE_CODE (type) == REFERENCE_TYPE
9678 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
9679 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
9681 static location_t last_loc;
9683 /* We keep track of the last time we issued this error
9684 message to avoid spewing a ton of messages during a
9685 single bad template instantiation. */
9686 if (complain & tf_error
9687 && last_loc != input_location)
9689 if (TREE_CODE (type) == VOID_TYPE)
9690 error ("forming reference to void");
9692 error ("forming %s to reference type %qT",
9693 (code == POINTER_TYPE) ? "pointer" : "reference",
9695 last_loc = input_location;
9698 return error_mark_node;
9700 else if (code == POINTER_TYPE)
9702 r = build_pointer_type (type);
9703 if (TREE_CODE (type) == METHOD_TYPE)
9704 r = build_ptrmemfunc_type (r);
9706 else if (TREE_CODE (type) == REFERENCE_TYPE)
9707 /* In C++0x, during template argument substitution, when there is an
9708 attempt to create a reference to a reference type, reference
9709 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
9711 "If a template-argument for a template-parameter T names a type
9712 that is a reference to a type A, an attempt to create the type
9713 'lvalue reference to cv T' creates the type 'lvalue reference to
9714 A,' while an attempt to create the type type rvalue reference to
9715 cv T' creates the type T"
9717 r = cp_build_reference_type
9719 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
9721 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
9722 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
9724 if (r != error_mark_node)
9725 /* Will this ever be needed for TYPE_..._TO values? */
9732 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
9733 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
9737 Type deduction may fail for any of the following
9740 -- Attempting to create "pointer to member of T" when T
9741 is not a class type. */
9742 if (complain & tf_error)
9743 error ("creating pointer to member of non-class type %qT", r);
9744 return error_mark_node;
9746 if (TREE_CODE (type) == REFERENCE_TYPE)
9748 if (complain & tf_error)
9749 error ("creating pointer to member reference type %qT", type);
9750 return error_mark_node;
9752 if (TREE_CODE (type) == VOID_TYPE)
9754 if (complain & tf_error)
9755 error ("creating pointer to member of type void");
9756 return error_mark_node;
9758 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
9759 if (TREE_CODE (type) == FUNCTION_TYPE)
9761 /* The type of the implicit object parameter gets its
9762 cv-qualifiers from the FUNCTION_TYPE. */
9764 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
9765 cp_type_quals (type));
9767 method_type = build_method_type_directly (this_type,
9769 TYPE_ARG_TYPES (type));
9770 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
9771 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
9775 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
9784 fntype = tsubst_function_type (t, args, complain, in_decl);
9785 if (fntype == error_mark_node)
9786 return error_mark_node;
9788 /* Substitute the exception specification. */
9789 specs = tsubst_exception_specification (t, args, complain,
9791 if (specs == error_mark_node)
9792 return error_mark_node;
9794 fntype = build_exception_variant (fntype, specs);
9799 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
9800 if (domain == error_mark_node)
9801 return error_mark_node;
9803 /* As an optimization, we avoid regenerating the array type if
9804 it will obviously be the same as T. */
9805 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
9808 /* These checks should match the ones in grokdeclarator.
9812 The deduction may fail for any of the following reasons:
9814 -- Attempting to create an array with an element type that
9815 is void, a function type, or a reference type, or [DR337]
9816 an abstract class type. */
9817 if (TREE_CODE (type) == VOID_TYPE
9818 || TREE_CODE (type) == FUNCTION_TYPE
9819 || TREE_CODE (type) == REFERENCE_TYPE)
9821 if (complain & tf_error)
9822 error ("creating array of %qT", type);
9823 return error_mark_node;
9825 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
9827 if (complain & tf_error)
9828 error ("creating array of %qT, which is an abstract class type",
9830 return error_mark_node;
9833 r = build_cplus_array_type (type, domain);
9835 if (TYPE_USER_ALIGN (t))
9837 TYPE_ALIGN (r) = TYPE_ALIGN (t);
9838 TYPE_USER_ALIGN (r) = 1;
9847 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9848 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9850 if (e1 == error_mark_node || e2 == error_mark_node)
9851 return error_mark_node;
9853 return fold_build2_loc (input_location,
9854 TREE_CODE (t), TREE_TYPE (t), e1, e2);
9860 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9861 if (e == error_mark_node)
9862 return error_mark_node;
9864 return fold_build1_loc (input_location, TREE_CODE (t), TREE_TYPE (t), e);
9869 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9870 in_decl, /*entering_scope=*/1);
9871 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
9874 if (ctx == error_mark_node || f == error_mark_node)
9875 return error_mark_node;
9877 if (!MAYBE_CLASS_TYPE_P (ctx))
9879 if (complain & tf_error)
9880 error ("%qT is not a class, struct, or union type", ctx);
9881 return error_mark_node;
9883 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
9885 /* Normally, make_typename_type does not require that the CTX
9886 have complete type in order to allow things like:
9888 template <class T> struct S { typename S<T>::X Y; };
9890 But, such constructs have already been resolved by this
9891 point, so here CTX really should have complete type, unless
9892 it's a partial instantiation. */
9893 if (!(complain & tf_no_class_instantiations))
9894 ctx = complete_type (ctx);
9895 if (!COMPLETE_TYPE_P (ctx))
9897 if (complain & tf_error)
9898 cxx_incomplete_type_error (NULL_TREE, ctx);
9899 return error_mark_node;
9903 f = make_typename_type (ctx, f, typename_type,
9904 (complain & tf_error) | tf_keep_type_decl);
9905 if (f == error_mark_node)
9907 if (TREE_CODE (f) == TYPE_DECL)
9909 complain |= tf_ignore_bad_quals;
9913 if (TREE_CODE (f) != TYPENAME_TYPE)
9915 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
9916 error ("%qT resolves to %qT, which is not an enumeration type",
9918 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
9919 error ("%qT resolves to %qT, which is is not a class type",
9923 return cp_build_qualified_type_real
9924 (f, cp_type_quals (f) | cp_type_quals (t), complain);
9927 case UNBOUND_CLASS_TEMPLATE:
9929 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9930 in_decl, /*entering_scope=*/1);
9931 tree name = TYPE_IDENTIFIER (t);
9932 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
9934 if (ctx == error_mark_node || name == error_mark_node)
9935 return error_mark_node;
9938 parm_list = tsubst_template_parms (parm_list, args, complain);
9939 return make_unbound_class_template (ctx, name, parm_list, complain);
9949 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9950 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
9951 /*integral_constant_expression_p=*/false);
9952 if (e1 == error_mark_node || e2 == error_mark_node)
9953 return error_mark_node;
9955 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
9960 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9961 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9962 if (e1 == error_mark_node || e2 == error_mark_node)
9963 return error_mark_node;
9965 return build_qualified_name (/*type=*/NULL_TREE,
9966 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
9973 type = finish_typeof (tsubst_expr
9974 (TYPEOF_TYPE_EXPR (t), args,
9976 /*integral_constant_expression_p=*/false));
9977 return cp_build_qualified_type_real (type,
9979 | cp_type_quals (type),
9987 ++cp_unevaluated_operand;
9988 ++c_inhibit_evaluation_warnings;
9990 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
9992 /*integral_constant_expression_p=*/false);
9994 --cp_unevaluated_operand;
9995 --c_inhibit_evaluation_warnings;
9998 finish_decltype_type (type,
9999 DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
10000 return cp_build_qualified_type_real (type,
10002 | cp_type_quals (type),
10006 case TYPE_ARGUMENT_PACK:
10007 case NONTYPE_ARGUMENT_PACK:
10009 tree r = make_node (TREE_CODE (t));
10011 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
10015 SET_ARGUMENT_PACK_ARGS (r, packed_out);
10017 /* For template nontype argument packs, also substitute into
10019 if (TREE_CODE (t) == NONTYPE_ARGUMENT_PACK)
10020 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
10027 sorry ("use of %qs in template",
10028 tree_code_name [(int) TREE_CODE (t)]);
10029 return error_mark_node;
10033 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
10034 type of the expression on the left-hand side of the "." or "->"
10038 tsubst_baselink (tree baselink, tree object_type,
10039 tree args, tsubst_flags_t complain, tree in_decl)
10042 tree qualifying_scope;
10045 tree template_args = 0;
10046 bool template_id_p = false;
10048 /* A baselink indicates a function from a base class. Both the
10049 BASELINK_ACCESS_BINFO and the base class referenced may
10050 indicate bases of the template class, rather than the
10051 instantiated class. In addition, lookups that were not
10052 ambiguous before may be ambiguous now. Therefore, we perform
10053 the lookup again. */
10054 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
10055 qualifying_scope = tsubst (qualifying_scope, args,
10056 complain, in_decl);
10057 fns = BASELINK_FUNCTIONS (baselink);
10058 optype = BASELINK_OPTYPE (baselink);
10059 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
10061 template_id_p = true;
10062 template_args = TREE_OPERAND (fns, 1);
10063 fns = TREE_OPERAND (fns, 0);
10065 template_args = tsubst_template_args (template_args, args,
10066 complain, in_decl);
10068 name = DECL_NAME (get_first_fn (fns));
10069 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
10071 /* If lookup found a single function, mark it as used at this
10072 point. (If it lookup found multiple functions the one selected
10073 later by overload resolution will be marked as used at that
10075 if (BASELINK_P (baselink))
10076 fns = BASELINK_FUNCTIONS (baselink);
10077 if (!template_id_p && !really_overloaded_fn (fns))
10078 mark_used (OVL_CURRENT (fns));
10080 /* Add back the template arguments, if present. */
10081 if (BASELINK_P (baselink) && template_id_p)
10082 BASELINK_FUNCTIONS (baselink)
10083 = build_nt (TEMPLATE_ID_EXPR,
10084 BASELINK_FUNCTIONS (baselink),
10086 /* Update the conversion operator type. */
10087 BASELINK_OPTYPE (baselink)
10088 = tsubst (optype, args, complain, in_decl);
10091 object_type = current_class_type;
10092 return adjust_result_of_qualified_name_lookup (baselink,
10097 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
10098 true if the qualified-id will be a postfix-expression in-and-of
10099 itself; false if more of the postfix-expression follows the
10100 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
10104 tsubst_qualified_id (tree qualified_id, tree args,
10105 tsubst_flags_t complain, tree in_decl,
10106 bool done, bool address_p)
10112 tree template_args;
10114 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
10116 /* Figure out what name to look up. */
10117 name = TREE_OPERAND (qualified_id, 1);
10118 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
10120 is_template = true;
10121 template_args = TREE_OPERAND (name, 1);
10123 template_args = tsubst_template_args (template_args, args,
10124 complain, in_decl);
10125 name = TREE_OPERAND (name, 0);
10129 is_template = false;
10130 template_args = NULL_TREE;
10133 /* Substitute into the qualifying scope. When there are no ARGS, we
10134 are just trying to simplify a non-dependent expression. In that
10135 case the qualifying scope may be dependent, and, in any case,
10136 substituting will not help. */
10137 scope = TREE_OPERAND (qualified_id, 0);
10140 scope = tsubst (scope, args, complain, in_decl);
10141 expr = tsubst_copy (name, args, complain, in_decl);
10146 if (dependent_type_p (scope))
10148 tree type = NULL_TREE;
10149 if (DECL_P (expr) && !dependent_scope_p (scope))
10150 type = TREE_TYPE (expr);
10151 return build_qualified_name (type, scope, expr,
10152 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
10155 if (!BASELINK_P (name) && !DECL_P (expr))
10157 if (TREE_CODE (expr) == BIT_NOT_EXPR)
10159 /* A BIT_NOT_EXPR is used to represent a destructor. */
10160 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
10162 error ("qualifying type %qT does not match destructor name ~%qT",
10163 scope, TREE_OPERAND (expr, 0));
10164 expr = error_mark_node;
10167 expr = lookup_qualified_name (scope, complete_dtor_identifier,
10168 /*is_type_p=*/0, false);
10171 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
10172 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
10173 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
10175 if (complain & tf_error)
10177 error ("dependent-name %qE is parsed as a non-type, but "
10178 "instantiation yields a type", qualified_id);
10179 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
10181 return error_mark_node;
10187 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
10189 /* Remember that there was a reference to this entity. */
10193 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
10195 if (complain & tf_error)
10196 qualified_name_lookup_error (scope,
10197 TREE_OPERAND (qualified_id, 1),
10198 expr, input_location);
10199 return error_mark_node;
10203 expr = lookup_template_function (expr, template_args);
10205 if (expr == error_mark_node && complain & tf_error)
10206 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
10207 expr, input_location);
10208 else if (TYPE_P (scope))
10210 expr = (adjust_result_of_qualified_name_lookup
10211 (expr, scope, current_class_type));
10212 expr = (finish_qualified_id_expr
10213 (scope, expr, done, address_p,
10214 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
10215 /*template_arg_p=*/false));
10218 /* Expressions do not generally have reference type. */
10219 if (TREE_CODE (expr) != SCOPE_REF
10220 /* However, if we're about to form a pointer-to-member, we just
10221 want the referenced member referenced. */
10222 && TREE_CODE (expr) != OFFSET_REF)
10223 expr = convert_from_reference (expr);
10228 /* Like tsubst, but deals with expressions. This function just replaces
10229 template parms; to finish processing the resultant expression, use
10233 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10235 enum tree_code code;
10238 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
10241 code = TREE_CODE (t);
10246 r = retrieve_local_specialization (t);
10251 /* This can happen for a parameter name used later in a function
10252 declaration (such as in a late-specified return type). Just
10253 make a dummy decl, since it's only used for its type. */
10254 gcc_assert (cp_unevaluated_operand != 0);
10255 /* We copy T because want to tsubst the PARM_DECL only,
10256 not the following PARM_DECLs that are chained to T. */
10258 r = tsubst_decl (c, args, complain);
10259 /* Give it the template pattern as its context; its true context
10260 hasn't been instantiated yet and this is good enough for
10262 DECL_CONTEXT (r) = DECL_CONTEXT (t);
10265 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
10266 r = ARGUMENT_PACK_SELECT_ARG (r);
10275 if (DECL_TEMPLATE_PARM_P (t))
10276 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
10277 /* There is no need to substitute into namespace-scope
10279 if (DECL_NAMESPACE_SCOPE_P (t))
10281 /* If ARGS is NULL, then T is known to be non-dependent. */
10282 if (args == NULL_TREE)
10283 return integral_constant_value (t);
10285 /* Unfortunately, we cannot just call lookup_name here.
10288 template <int I> int f() {
10290 struct S { void g() { E e = a; } };
10293 When we instantiate f<7>::S::g(), say, lookup_name is not
10294 clever enough to find f<7>::a. */
10296 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
10297 /*entering_scope=*/0);
10299 for (v = TYPE_VALUES (enum_type);
10301 v = TREE_CHAIN (v))
10302 if (TREE_PURPOSE (v) == DECL_NAME (t))
10303 return TREE_VALUE (v);
10305 /* We didn't find the name. That should never happen; if
10306 name-lookup found it during preliminary parsing, we
10307 should find it again here during instantiation. */
10308 gcc_unreachable ();
10313 if (DECL_CONTEXT (t))
10317 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
10318 /*entering_scope=*/1);
10319 if (ctx != DECL_CONTEXT (t))
10321 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
10324 if (complain & tf_error)
10325 error ("using invalid field %qD", t);
10326 return error_mark_node;
10335 case FUNCTION_DECL:
10336 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
10337 || local_variable_p (t))
10338 t = tsubst (t, args, complain, in_decl);
10343 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
10345 case TEMPLATE_DECL:
10346 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
10347 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
10348 args, complain, in_decl);
10349 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
10350 return tsubst (t, args, complain, in_decl);
10351 else if (DECL_CLASS_SCOPE_P (t)
10352 && uses_template_parms (DECL_CONTEXT (t)))
10354 /* Template template argument like the following example need
10357 template <template <class> class TT> struct C {};
10358 template <class T> struct D {
10359 template <class U> struct E {};
10364 We are processing the template argument `E' in #1 for
10365 the template instantiation #2. Originally, `E' is a
10366 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
10367 have to substitute this with one having context `D<int>'. */
10369 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
10370 return lookup_field (context, DECL_NAME(t), 0, false);
10373 /* Ordinary template template argument. */
10377 case REINTERPRET_CAST_EXPR:
10378 case CONST_CAST_EXPR:
10379 case STATIC_CAST_EXPR:
10380 case DYNAMIC_CAST_EXPR:
10383 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10384 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10387 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
10389 /* We only want to compute the number of arguments. */
10390 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
10391 complain, in_decl);
10394 if (TREE_CODE (expanded) == TREE_VEC)
10395 len = TREE_VEC_LENGTH (expanded);
10397 if (expanded == error_mark_node)
10398 return error_mark_node;
10399 else if (PACK_EXPANSION_P (expanded)
10400 || (TREE_CODE (expanded) == TREE_VEC
10402 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
10404 if (TREE_CODE (expanded) == TREE_VEC)
10405 expanded = TREE_VEC_ELT (expanded, len - 1);
10407 if (TYPE_P (expanded))
10408 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
10409 complain & tf_error);
10411 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
10412 complain & tf_error);
10415 return build_int_cst (size_type_node, len);
10421 case TRUTH_NOT_EXPR:
10424 case UNARY_PLUS_EXPR: /* Unary + */
10429 case REALPART_EXPR:
10430 case IMAGPART_EXPR:
10432 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10433 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10435 case COMPONENT_REF:
10440 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
10441 name = TREE_OPERAND (t, 1);
10442 if (TREE_CODE (name) == BIT_NOT_EXPR)
10444 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10445 complain, in_decl);
10446 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10448 else if (TREE_CODE (name) == SCOPE_REF
10449 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
10451 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
10452 complain, in_decl);
10453 name = TREE_OPERAND (name, 1);
10454 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10455 complain, in_decl);
10456 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10457 name = build_qualified_name (/*type=*/NULL_TREE,
10459 /*template_p=*/false);
10461 else if (TREE_CODE (name) == BASELINK)
10462 name = tsubst_baselink (name,
10463 non_reference (TREE_TYPE (object)),
10467 name = tsubst_copy (name, args, complain, in_decl);
10468 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
10474 case TRUNC_DIV_EXPR:
10475 case CEIL_DIV_EXPR:
10476 case FLOOR_DIV_EXPR:
10477 case ROUND_DIV_EXPR:
10478 case EXACT_DIV_EXPR:
10482 case TRUNC_MOD_EXPR:
10483 case FLOOR_MOD_EXPR:
10484 case TRUTH_ANDIF_EXPR:
10485 case TRUTH_ORIF_EXPR:
10486 case TRUTH_AND_EXPR:
10487 case TRUTH_OR_EXPR:
10500 case COMPOUND_EXPR:
10503 case PREDECREMENT_EXPR:
10504 case PREINCREMENT_EXPR:
10505 case POSTDECREMENT_EXPR:
10506 case POSTINCREMENT_EXPR:
10508 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10509 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10512 return build_qualified_name (/*type=*/NULL_TREE,
10513 tsubst_copy (TREE_OPERAND (t, 0),
10514 args, complain, in_decl),
10515 tsubst_copy (TREE_OPERAND (t, 1),
10516 args, complain, in_decl),
10517 QUALIFIED_NAME_IS_TEMPLATE (t));
10522 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10523 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10524 NULL_TREE, NULL_TREE);
10528 int n = VL_EXP_OPERAND_LENGTH (t);
10529 tree result = build_vl_exp (CALL_EXPR, n);
10531 for (i = 0; i < n; i++)
10532 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
10533 complain, in_decl);
10539 case PSEUDO_DTOR_EXPR:
10542 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10543 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10544 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10545 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
10552 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10553 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10554 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10555 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
10562 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10563 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10564 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
10565 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
10569 case TEMPLATE_ID_EXPR:
10571 /* Substituted template arguments */
10572 tree fn = TREE_OPERAND (t, 0);
10573 tree targs = TREE_OPERAND (t, 1);
10575 fn = tsubst_copy (fn, args, complain, in_decl);
10577 targs = tsubst_template_args (targs, args, complain, in_decl);
10579 return lookup_template_function (fn, targs);
10584 tree purpose, value, chain;
10586 if (t == void_list_node)
10589 purpose = TREE_PURPOSE (t);
10591 purpose = tsubst_copy (purpose, args, complain, in_decl);
10592 value = TREE_VALUE (t);
10594 value = tsubst_copy (value, args, complain, in_decl);
10595 chain = TREE_CHAIN (t);
10596 if (chain && chain != void_type_node)
10597 chain = tsubst_copy (chain, args, complain, in_decl);
10598 if (purpose == TREE_PURPOSE (t)
10599 && value == TREE_VALUE (t)
10600 && chain == TREE_CHAIN (t))
10602 return tree_cons (purpose, value, chain);
10607 case ENUMERAL_TYPE:
10609 case TEMPLATE_TYPE_PARM:
10610 case TEMPLATE_TEMPLATE_PARM:
10611 case BOUND_TEMPLATE_TEMPLATE_PARM:
10612 case TEMPLATE_PARM_INDEX:
10614 case REFERENCE_TYPE:
10616 case FUNCTION_TYPE:
10619 case TYPENAME_TYPE:
10620 case UNBOUND_CLASS_TEMPLATE:
10622 case DECLTYPE_TYPE:
10624 return tsubst (t, args, complain, in_decl);
10626 case IDENTIFIER_NODE:
10627 if (IDENTIFIER_TYPENAME_P (t))
10629 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10630 return mangle_conv_op_name_for_type (new_type);
10636 /* This is handled by tsubst_copy_and_build. */
10637 gcc_unreachable ();
10640 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
10642 tsubst (TREE_TYPE (t), args, complain, in_decl));
10644 case CLEANUP_POINT_EXPR:
10645 /* We shouldn't have built any of these during initial template
10646 generation. Instead, they should be built during instantiation
10647 in response to the saved STMT_IS_FULL_EXPR_P setting. */
10648 gcc_unreachable ();
10651 mark_used (TREE_OPERAND (t, 1));
10654 case EXPR_PACK_EXPANSION:
10655 error ("invalid use of pack expansion expression");
10656 return error_mark_node;
10658 case NONTYPE_ARGUMENT_PACK:
10659 error ("use %<...%> to expand argument pack");
10660 return error_mark_node;
10667 /* Like tsubst_copy, but specifically for OpenMP clauses. */
10670 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
10673 tree new_clauses = NULL, nc, oc;
10675 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
10677 nc = copy_node (oc);
10678 OMP_CLAUSE_CHAIN (nc) = new_clauses;
10681 switch (OMP_CLAUSE_CODE (nc))
10683 case OMP_CLAUSE_LASTPRIVATE:
10684 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
10686 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
10687 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
10688 in_decl, /*integral_constant_expression_p=*/false);
10689 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
10690 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
10693 case OMP_CLAUSE_PRIVATE:
10694 case OMP_CLAUSE_SHARED:
10695 case OMP_CLAUSE_FIRSTPRIVATE:
10696 case OMP_CLAUSE_REDUCTION:
10697 case OMP_CLAUSE_COPYIN:
10698 case OMP_CLAUSE_COPYPRIVATE:
10699 case OMP_CLAUSE_IF:
10700 case OMP_CLAUSE_NUM_THREADS:
10701 case OMP_CLAUSE_SCHEDULE:
10702 case OMP_CLAUSE_COLLAPSE:
10703 OMP_CLAUSE_OPERAND (nc, 0)
10704 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
10705 in_decl, /*integral_constant_expression_p=*/false);
10707 case OMP_CLAUSE_NOWAIT:
10708 case OMP_CLAUSE_ORDERED:
10709 case OMP_CLAUSE_DEFAULT:
10710 case OMP_CLAUSE_UNTIED:
10713 gcc_unreachable ();
10717 return finish_omp_clauses (nreverse (new_clauses));
10720 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
10723 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
10726 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
10728 tree purpose, value, chain;
10733 if (TREE_CODE (t) != TREE_LIST)
10734 return tsubst_copy_and_build (t, args, complain, in_decl,
10735 /*function_p=*/false,
10736 /*integral_constant_expression_p=*/false);
10738 if (t == void_list_node)
10741 purpose = TREE_PURPOSE (t);
10743 purpose = RECUR (purpose);
10744 value = TREE_VALUE (t);
10746 value = RECUR (value);
10747 chain = TREE_CHAIN (t);
10748 if (chain && chain != void_type_node)
10749 chain = RECUR (chain);
10750 return tree_cons (purpose, value, chain);
10754 /* Substitute one OMP_FOR iterator. */
10757 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
10758 tree condv, tree incrv, tree *clauses,
10759 tree args, tsubst_flags_t complain, tree in_decl,
10760 bool integral_constant_expression_p)
10762 #define RECUR(NODE) \
10763 tsubst_expr ((NODE), args, complain, in_decl, \
10764 integral_constant_expression_p)
10765 tree decl, init, cond, incr, auto_node;
10767 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
10768 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
10769 decl = RECUR (TREE_OPERAND (init, 0));
10770 init = TREE_OPERAND (init, 1);
10771 auto_node = type_uses_auto (TREE_TYPE (decl));
10772 if (auto_node && init)
10774 tree init_expr = init;
10775 if (TREE_CODE (init_expr) == DECL_EXPR)
10776 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
10777 init_expr = RECUR (init_expr);
10779 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
10781 gcc_assert (!type_dependent_expression_p (decl));
10783 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
10785 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
10786 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
10787 if (TREE_CODE (incr) == MODIFY_EXPR)
10788 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
10789 RECUR (TREE_OPERAND (incr, 1)),
10792 incr = RECUR (incr);
10793 TREE_VEC_ELT (declv, i) = decl;
10794 TREE_VEC_ELT (initv, i) = init;
10795 TREE_VEC_ELT (condv, i) = cond;
10796 TREE_VEC_ELT (incrv, i) = incr;
10800 if (init && TREE_CODE (init) != DECL_EXPR)
10803 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
10805 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
10806 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
10807 && OMP_CLAUSE_DECL (c) == decl)
10809 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
10810 && OMP_CLAUSE_DECL (c) == decl)
10811 error ("iteration variable %qD should not be firstprivate", decl);
10812 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
10813 && OMP_CLAUSE_DECL (c) == decl)
10814 error ("iteration variable %qD should not be reduction", decl);
10818 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
10819 OMP_CLAUSE_DECL (c) = decl;
10820 c = finish_omp_clauses (c);
10823 OMP_CLAUSE_CHAIN (c) = *clauses;
10828 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
10829 if (COMPARISON_CLASS_P (cond))
10830 cond = build2 (TREE_CODE (cond), boolean_type_node,
10831 RECUR (TREE_OPERAND (cond, 0)),
10832 RECUR (TREE_OPERAND (cond, 1)));
10834 cond = RECUR (cond);
10835 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
10836 switch (TREE_CODE (incr))
10838 case PREINCREMENT_EXPR:
10839 case PREDECREMENT_EXPR:
10840 case POSTINCREMENT_EXPR:
10841 case POSTDECREMENT_EXPR:
10842 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
10843 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
10846 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
10847 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
10849 tree rhs = TREE_OPERAND (incr, 1);
10850 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
10851 RECUR (TREE_OPERAND (incr, 0)),
10852 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
10853 RECUR (TREE_OPERAND (rhs, 0)),
10854 RECUR (TREE_OPERAND (rhs, 1))));
10857 incr = RECUR (incr);
10860 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
10861 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
10863 tree lhs = RECUR (TREE_OPERAND (incr, 0));
10864 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
10865 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
10866 TREE_TYPE (decl), lhs,
10867 RECUR (TREE_OPERAND (incr, 2))));
10869 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
10870 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
10871 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
10873 tree rhs = TREE_OPERAND (incr, 2);
10874 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
10875 RECUR (TREE_OPERAND (incr, 0)),
10876 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
10877 RECUR (TREE_OPERAND (rhs, 0)),
10878 RECUR (TREE_OPERAND (rhs, 1))));
10881 incr = RECUR (incr);
10884 incr = RECUR (incr);
10888 TREE_VEC_ELT (declv, i) = decl;
10889 TREE_VEC_ELT (initv, i) = init;
10890 TREE_VEC_ELT (condv, i) = cond;
10891 TREE_VEC_ELT (incrv, i) = incr;
10895 /* Like tsubst_copy for expressions, etc. but also does semantic
10899 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
10900 bool integral_constant_expression_p)
10902 #define RECUR(NODE) \
10903 tsubst_expr ((NODE), args, complain, in_decl, \
10904 integral_constant_expression_p)
10908 if (t == NULL_TREE || t == error_mark_node)
10911 if (EXPR_HAS_LOCATION (t))
10912 input_location = EXPR_LOCATION (t);
10913 if (STATEMENT_CODE_P (TREE_CODE (t)))
10914 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
10916 switch (TREE_CODE (t))
10918 case STATEMENT_LIST:
10920 tree_stmt_iterator i;
10921 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
10922 RECUR (tsi_stmt (i));
10926 case CTOR_INITIALIZER:
10927 finish_mem_initializers (tsubst_initializer_list
10928 (TREE_OPERAND (t, 0), args));
10932 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
10936 tmp = RECUR (EXPR_STMT_EXPR (t));
10937 if (EXPR_STMT_STMT_EXPR_RESULT (t))
10938 finish_stmt_expr_expr (tmp, cur_stmt_expr);
10940 finish_expr_stmt (tmp);
10944 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
10952 decl = DECL_EXPR_DECL (t);
10953 if (TREE_CODE (decl) == LABEL_DECL)
10954 finish_label_decl (DECL_NAME (decl));
10955 else if (TREE_CODE (decl) == USING_DECL)
10957 tree scope = USING_DECL_SCOPE (decl);
10958 tree name = DECL_NAME (decl);
10961 scope = RECUR (scope);
10962 decl = lookup_qualified_name (scope, name,
10963 /*is_type_p=*/false,
10964 /*complain=*/false);
10965 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
10966 qualified_name_lookup_error (scope, name, decl, input_location);
10968 do_local_using_decl (decl, scope, name);
10972 init = DECL_INITIAL (decl);
10973 decl = tsubst (decl, args, complain, in_decl);
10974 if (decl != error_mark_node)
10976 /* By marking the declaration as instantiated, we avoid
10977 trying to instantiate it. Since instantiate_decl can't
10978 handle local variables, and since we've already done
10979 all that needs to be done, that's the right thing to
10981 if (TREE_CODE (decl) == VAR_DECL)
10982 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
10983 if (TREE_CODE (decl) == VAR_DECL
10984 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
10985 /* Anonymous aggregates are a special case. */
10986 finish_anon_union (decl);
10989 maybe_push_decl (decl);
10990 if (TREE_CODE (decl) == VAR_DECL
10991 && DECL_PRETTY_FUNCTION_P (decl))
10993 /* For __PRETTY_FUNCTION__ we have to adjust the
10995 const char *const name
10996 = cxx_printable_name (current_function_decl, 2);
10997 init = cp_fname_init (name, &TREE_TYPE (decl));
11001 tree t = RECUR (init);
11004 /* If we had an initializer but it
11005 instantiated to nothing,
11006 value-initialize the object. This will
11007 only occur when the initializer was a
11008 pack expansion where the parameter packs
11009 used in that expansion were of length
11011 init = build_value_init (TREE_TYPE (decl));
11016 cp_finish_decl (decl, init, false, NULL_TREE, 0);
11021 /* A DECL_EXPR can also be used as an expression, in the condition
11022 clause of an if/for/while construct. */
11027 stmt = begin_for_stmt ();
11028 RECUR (FOR_INIT_STMT (t));
11029 finish_for_init_stmt (stmt);
11030 tmp = RECUR (FOR_COND (t));
11031 finish_for_cond (tmp, stmt);
11032 tmp = RECUR (FOR_EXPR (t));
11033 finish_for_expr (tmp, stmt);
11034 RECUR (FOR_BODY (t));
11035 finish_for_stmt (stmt);
11039 stmt = begin_while_stmt ();
11040 tmp = RECUR (WHILE_COND (t));
11041 finish_while_stmt_cond (tmp, stmt);
11042 RECUR (WHILE_BODY (t));
11043 finish_while_stmt (stmt);
11047 stmt = begin_do_stmt ();
11048 RECUR (DO_BODY (t));
11049 finish_do_body (stmt);
11050 tmp = RECUR (DO_COND (t));
11051 finish_do_stmt (tmp, stmt);
11055 stmt = begin_if_stmt ();
11056 tmp = RECUR (IF_COND (t));
11057 finish_if_stmt_cond (tmp, stmt);
11058 RECUR (THEN_CLAUSE (t));
11059 finish_then_clause (stmt);
11061 if (ELSE_CLAUSE (t))
11063 begin_else_clause (stmt);
11064 RECUR (ELSE_CLAUSE (t));
11065 finish_else_clause (stmt);
11068 finish_if_stmt (stmt);
11072 if (BIND_EXPR_BODY_BLOCK (t))
11073 stmt = begin_function_body ();
11075 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
11076 ? BCS_TRY_BLOCK : 0);
11078 RECUR (BIND_EXPR_BODY (t));
11080 if (BIND_EXPR_BODY_BLOCK (t))
11081 finish_function_body (stmt);
11083 finish_compound_stmt (stmt);
11087 finish_break_stmt ();
11090 case CONTINUE_STMT:
11091 finish_continue_stmt ();
11095 stmt = begin_switch_stmt ();
11096 tmp = RECUR (SWITCH_STMT_COND (t));
11097 finish_switch_cond (tmp, stmt);
11098 RECUR (SWITCH_STMT_BODY (t));
11099 finish_switch_stmt (stmt);
11102 case CASE_LABEL_EXPR:
11103 finish_case_label (EXPR_LOCATION (t),
11104 RECUR (CASE_LOW (t)),
11105 RECUR (CASE_HIGH (t)));
11110 tree decl = LABEL_EXPR_LABEL (t);
11113 label = finish_label_stmt (DECL_NAME (decl));
11114 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
11115 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
11120 tmp = GOTO_DESTINATION (t);
11121 if (TREE_CODE (tmp) != LABEL_DECL)
11122 /* Computed goto's must be tsubst'd into. On the other hand,
11123 non-computed gotos must not be; the identifier in question
11124 will have no binding. */
11127 tmp = DECL_NAME (tmp);
11128 finish_goto_stmt (tmp);
11132 tmp = finish_asm_stmt
11133 (ASM_VOLATILE_P (t),
11134 RECUR (ASM_STRING (t)),
11135 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
11136 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
11137 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl));
11139 tree asm_expr = tmp;
11140 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
11141 asm_expr = TREE_OPERAND (asm_expr, 0);
11142 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
11149 stmt = begin_try_block ();
11150 RECUR (TRY_STMTS (t));
11151 finish_cleanup_try_block (stmt);
11152 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
11156 tree compound_stmt = NULL_TREE;
11158 if (FN_TRY_BLOCK_P (t))
11159 stmt = begin_function_try_block (&compound_stmt);
11161 stmt = begin_try_block ();
11163 RECUR (TRY_STMTS (t));
11165 if (FN_TRY_BLOCK_P (t))
11166 finish_function_try_block (stmt);
11168 finish_try_block (stmt);
11170 RECUR (TRY_HANDLERS (t));
11171 if (FN_TRY_BLOCK_P (t))
11172 finish_function_handler_sequence (stmt, compound_stmt);
11174 finish_handler_sequence (stmt);
11180 tree decl = HANDLER_PARMS (t);
11184 decl = tsubst (decl, args, complain, in_decl);
11185 /* Prevent instantiate_decl from trying to instantiate
11186 this variable. We've already done all that needs to be
11188 if (decl != error_mark_node)
11189 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11191 stmt = begin_handler ();
11192 finish_handler_parms (decl, stmt);
11193 RECUR (HANDLER_BODY (t));
11194 finish_handler (stmt);
11199 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
11202 case STATIC_ASSERT:
11205 tsubst_expr (STATIC_ASSERT_CONDITION (t),
11208 /*integral_constant_expression_p=*/true);
11209 finish_static_assert (condition,
11210 STATIC_ASSERT_MESSAGE (t),
11211 STATIC_ASSERT_SOURCE_LOCATION (t),
11212 /*member_p=*/false);
11217 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
11218 args, complain, in_decl);
11219 stmt = begin_omp_parallel ();
11220 RECUR (OMP_PARALLEL_BODY (t));
11221 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
11222 = OMP_PARALLEL_COMBINED (t);
11226 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
11227 args, complain, in_decl);
11228 stmt = begin_omp_task ();
11229 RECUR (OMP_TASK_BODY (t));
11230 finish_omp_task (tmp, stmt);
11235 tree clauses, body, pre_body;
11236 tree declv, initv, condv, incrv;
11239 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
11240 args, complain, in_decl);
11241 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11242 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11243 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11244 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11246 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
11247 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
11248 &clauses, args, complain, in_decl,
11249 integral_constant_expression_p);
11251 stmt = begin_omp_structured_block ();
11253 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
11254 if (TREE_VEC_ELT (initv, i) == NULL
11255 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
11256 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
11257 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
11259 tree init = RECUR (TREE_VEC_ELT (initv, i));
11260 gcc_assert (init == TREE_VEC_ELT (declv, i));
11261 TREE_VEC_ELT (initv, i) = NULL_TREE;
11265 tree decl_expr = TREE_VEC_ELT (initv, i);
11266 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
11267 gcc_assert (init != NULL);
11268 TREE_VEC_ELT (initv, i) = RECUR (init);
11269 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
11271 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
11274 pre_body = push_stmt_list ();
11275 RECUR (OMP_FOR_PRE_BODY (t));
11276 pre_body = pop_stmt_list (pre_body);
11278 body = push_stmt_list ();
11279 RECUR (OMP_FOR_BODY (t));
11280 body = pop_stmt_list (body);
11282 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
11283 body, pre_body, clauses);
11285 add_stmt (finish_omp_structured_block (stmt));
11291 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
11292 stmt = push_stmt_list ();
11293 RECUR (OMP_BODY (t));
11294 stmt = pop_stmt_list (stmt);
11297 OMP_BODY (t) = stmt;
11298 OMP_CLAUSES (t) = tmp;
11306 stmt = push_stmt_list ();
11307 RECUR (OMP_BODY (t));
11308 stmt = pop_stmt_list (stmt);
11311 OMP_BODY (t) = stmt;
11316 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
11318 tree op1 = TREE_OPERAND (t, 1);
11319 tree lhs = RECUR (TREE_OPERAND (op1, 0));
11320 tree rhs = RECUR (TREE_OPERAND (op1, 1));
11321 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
11325 case EXPR_PACK_EXPANSION:
11326 error ("invalid use of pack expansion expression");
11327 return error_mark_node;
11329 case NONTYPE_ARGUMENT_PACK:
11330 error ("use %<...%> to expand argument pack");
11331 return error_mark_node;
11334 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
11336 return tsubst_copy_and_build (t, args, complain, in_decl,
11337 /*function_p=*/false,
11338 integral_constant_expression_p);
11345 /* T is a postfix-expression that is not being used in a function
11346 call. Return the substituted version of T. */
11349 tsubst_non_call_postfix_expression (tree t, tree args,
11350 tsubst_flags_t complain,
11353 if (TREE_CODE (t) == SCOPE_REF)
11354 t = tsubst_qualified_id (t, args, complain, in_decl,
11355 /*done=*/false, /*address_p=*/false);
11357 t = tsubst_copy_and_build (t, args, complain, in_decl,
11358 /*function_p=*/false,
11359 /*integral_constant_expression_p=*/false);
11364 /* Like tsubst but deals with expressions and performs semantic
11365 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
11368 tsubst_copy_and_build (tree t,
11370 tsubst_flags_t complain,
11373 bool integral_constant_expression_p)
11375 #define RECUR(NODE) \
11376 tsubst_copy_and_build (NODE, args, complain, in_decl, \
11377 /*function_p=*/false, \
11378 integral_constant_expression_p)
11382 if (t == NULL_TREE || t == error_mark_node)
11385 switch (TREE_CODE (t))
11389 /* Fall through. */
11390 case IDENTIFIER_NODE:
11394 bool non_integral_constant_expression_p;
11395 const char *error_msg;
11397 if (IDENTIFIER_TYPENAME_P (t))
11399 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11400 t = mangle_conv_op_name_for_type (new_type);
11403 /* Look up the name. */
11404 decl = lookup_name (t);
11406 /* By convention, expressions use ERROR_MARK_NODE to indicate
11407 failure, not NULL_TREE. */
11408 if (decl == NULL_TREE)
11409 decl = error_mark_node;
11411 decl = finish_id_expression (t, decl, NULL_TREE,
11413 integral_constant_expression_p,
11414 /*allow_non_integral_constant_expression_p=*/false,
11415 &non_integral_constant_expression_p,
11416 /*template_p=*/false,
11418 /*address_p=*/false,
11419 /*template_arg_p=*/false,
11424 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
11425 decl = unqualified_name_lookup_error (decl);
11429 case TEMPLATE_ID_EXPR:
11432 tree templ = RECUR (TREE_OPERAND (t, 0));
11433 tree targs = TREE_OPERAND (t, 1);
11436 targs = tsubst_template_args (targs, args, complain, in_decl);
11438 if (TREE_CODE (templ) == COMPONENT_REF)
11440 object = TREE_OPERAND (templ, 0);
11441 templ = TREE_OPERAND (templ, 1);
11444 object = NULL_TREE;
11445 templ = lookup_template_function (templ, targs);
11448 return build3 (COMPONENT_REF, TREE_TYPE (templ),
11449 object, templ, NULL_TREE);
11451 return baselink_for_fns (templ);
11456 tree r = RECUR (TREE_OPERAND (t, 0));
11458 if (REFERENCE_REF_P (t))
11460 /* A type conversion to reference type will be enclosed in
11461 such an indirect ref, but the substitution of the cast
11462 will have also added such an indirect ref. */
11463 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
11464 r = convert_from_reference (r);
11467 r = build_x_indirect_ref (r, "unary *", complain);
11473 (tsubst (TREE_TYPE (t), args, complain, in_decl),
11474 RECUR (TREE_OPERAND (t, 0)));
11477 case REINTERPRET_CAST_EXPR:
11478 case CONST_CAST_EXPR:
11479 case DYNAMIC_CAST_EXPR:
11480 case STATIC_CAST_EXPR:
11485 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11486 if (integral_constant_expression_p
11487 && !cast_valid_in_integral_constant_expression_p (type))
11489 if (complain & tf_error)
11490 error ("a cast to a type other than an integral or "
11491 "enumeration type cannot appear in a constant-expression");
11492 return error_mark_node;
11495 op = RECUR (TREE_OPERAND (t, 0));
11497 switch (TREE_CODE (t))
11500 return build_functional_cast (type, op, complain);
11501 case REINTERPRET_CAST_EXPR:
11502 return build_reinterpret_cast (type, op, complain);
11503 case CONST_CAST_EXPR:
11504 return build_const_cast (type, op, complain);
11505 case DYNAMIC_CAST_EXPR:
11506 return build_dynamic_cast (type, op, complain);
11507 case STATIC_CAST_EXPR:
11508 return build_static_cast (type, op, complain);
11510 gcc_unreachable ();
11514 case POSTDECREMENT_EXPR:
11515 case POSTINCREMENT_EXPR:
11516 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11517 args, complain, in_decl);
11518 return build_x_unary_op (TREE_CODE (t), op1, complain);
11520 case PREDECREMENT_EXPR:
11521 case PREINCREMENT_EXPR:
11525 case TRUTH_NOT_EXPR:
11526 case UNARY_PLUS_EXPR: /* Unary + */
11527 case REALPART_EXPR:
11528 case IMAGPART_EXPR:
11529 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
11533 op1 = TREE_OPERAND (t, 0);
11534 if (TREE_CODE (op1) == SCOPE_REF)
11535 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
11536 /*done=*/true, /*address_p=*/true);
11538 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
11540 if (TREE_CODE (op1) == LABEL_DECL)
11541 return finish_label_address_expr (DECL_NAME (op1),
11542 EXPR_LOCATION (op1));
11543 return build_x_unary_op (ADDR_EXPR, op1, complain);
11548 case TRUNC_DIV_EXPR:
11549 case CEIL_DIV_EXPR:
11550 case FLOOR_DIV_EXPR:
11551 case ROUND_DIV_EXPR:
11552 case EXACT_DIV_EXPR:
11556 case TRUNC_MOD_EXPR:
11557 case FLOOR_MOD_EXPR:
11558 case TRUTH_ANDIF_EXPR:
11559 case TRUTH_ORIF_EXPR:
11560 case TRUTH_AND_EXPR:
11561 case TRUTH_OR_EXPR:
11576 return build_x_binary_op
11578 RECUR (TREE_OPERAND (t, 0)),
11579 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
11581 : TREE_CODE (TREE_OPERAND (t, 0))),
11582 RECUR (TREE_OPERAND (t, 1)),
11583 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
11585 : TREE_CODE (TREE_OPERAND (t, 1))),
11586 /*overloaded_p=*/NULL,
11590 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
11591 /*address_p=*/false);
11593 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11594 args, complain, in_decl);
11595 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
11598 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11599 return tsubst_copy (t, args, complain, in_decl);
11603 op1 = TREE_OPERAND (t, 0);
11606 /* When there are no ARGS, we are trying to evaluate a
11607 non-dependent expression from the parser. Trying to do
11608 the substitutions may not work. */
11610 op1 = TREE_TYPE (op1);
11614 ++cp_unevaluated_operand;
11615 ++c_inhibit_evaluation_warnings;
11616 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
11617 /*function_p=*/false,
11618 /*integral_constant_expression_p=*/false);
11619 --cp_unevaluated_operand;
11620 --c_inhibit_evaluation_warnings;
11623 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
11624 complain & tf_error);
11626 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
11627 complain & tf_error);
11631 tree r = build_x_modify_expr
11632 (RECUR (TREE_OPERAND (t, 0)),
11633 TREE_CODE (TREE_OPERAND (t, 1)),
11634 RECUR (TREE_OPERAND (t, 2)),
11636 /* TREE_NO_WARNING must be set if either the expression was
11637 parenthesized or it uses an operator such as >>= rather
11638 than plain assignment. In the former case, it was already
11639 set and must be copied. In the latter case,
11640 build_x_modify_expr sets it and it must not be reset
11642 if (TREE_NO_WARNING (t))
11643 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11648 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11649 args, complain, in_decl);
11650 /* Remember that there was a reference to this entity. */
11653 return build_x_arrow (op1);
11657 tree placement = RECUR (TREE_OPERAND (t, 0));
11658 tree init = RECUR (TREE_OPERAND (t, 3));
11659 VEC(tree,gc) *placement_vec;
11660 VEC(tree,gc) *init_vec;
11663 if (placement == NULL_TREE)
11664 placement_vec = NULL;
11667 placement_vec = make_tree_vector ();
11668 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
11669 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
11672 /* If there was an initializer in the original tree, but it
11673 instantiated to an empty list, then we should pass a
11674 non-NULL empty vector to tell build_new that it was an
11675 empty initializer() rather than no initializer. This can
11676 only happen when the initializer is a pack expansion whose
11677 parameter packs are of length zero. */
11678 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
11682 init_vec = make_tree_vector ();
11683 if (init == void_zero_node)
11684 gcc_assert (init_vec != NULL);
11687 for (; init != NULL_TREE; init = TREE_CHAIN (init))
11688 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
11692 ret = build_new (&placement_vec,
11693 RECUR (TREE_OPERAND (t, 1)),
11694 RECUR (TREE_OPERAND (t, 2)),
11696 NEW_EXPR_USE_GLOBAL (t),
11699 if (placement_vec != NULL)
11700 release_tree_vector (placement_vec);
11701 if (init_vec != NULL)
11702 release_tree_vector (init_vec);
11708 return delete_sanity
11709 (RECUR (TREE_OPERAND (t, 0)),
11710 RECUR (TREE_OPERAND (t, 1)),
11711 DELETE_EXPR_USE_VEC (t),
11712 DELETE_EXPR_USE_GLOBAL (t));
11714 case COMPOUND_EXPR:
11715 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
11716 RECUR (TREE_OPERAND (t, 1)),
11722 VEC(tree,gc) *call_args;
11723 unsigned int nargs, i;
11728 function = CALL_EXPR_FN (t);
11729 /* When we parsed the expression, we determined whether or
11730 not Koenig lookup should be performed. */
11731 koenig_p = KOENIG_LOOKUP_P (t);
11732 if (TREE_CODE (function) == SCOPE_REF)
11734 qualified_p = true;
11735 function = tsubst_qualified_id (function, args, complain, in_decl,
11737 /*address_p=*/false);
11741 if (TREE_CODE (function) == COMPONENT_REF)
11743 tree op = TREE_OPERAND (function, 1);
11745 qualified_p = (TREE_CODE (op) == SCOPE_REF
11746 || (BASELINK_P (op)
11747 && BASELINK_QUALIFIED_P (op)));
11750 qualified_p = false;
11752 function = tsubst_copy_and_build (function, args, complain,
11755 integral_constant_expression_p);
11757 if (BASELINK_P (function))
11758 qualified_p = true;
11761 nargs = call_expr_nargs (t);
11762 call_args = make_tree_vector ();
11763 for (i = 0; i < nargs; ++i)
11765 tree arg = CALL_EXPR_ARG (t, i);
11767 if (!PACK_EXPANSION_P (arg))
11768 VEC_safe_push (tree, gc, call_args,
11769 RECUR (CALL_EXPR_ARG (t, i)));
11772 /* Expand the pack expansion and push each entry onto
11774 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
11775 if (TREE_CODE (arg) == TREE_VEC)
11777 unsigned int len, j;
11779 len = TREE_VEC_LENGTH (arg);
11780 for (j = 0; j < len; ++j)
11782 tree value = TREE_VEC_ELT (arg, j);
11783 if (value != NULL_TREE)
11784 value = convert_from_reference (value);
11785 VEC_safe_push (tree, gc, call_args, value);
11790 /* A partial substitution. Add one entry. */
11791 VEC_safe_push (tree, gc, call_args, arg);
11796 /* We do not perform argument-dependent lookup if normal
11797 lookup finds a non-function, in accordance with the
11798 expected resolution of DR 218. */
11800 && ((is_overloaded_fn (function)
11801 /* If lookup found a member function, the Koenig lookup is
11802 not appropriate, even if an unqualified-name was used
11803 to denote the function. */
11804 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
11805 || TREE_CODE (function) == IDENTIFIER_NODE)
11806 /* Only do this when substitution turns a dependent call
11807 into a non-dependent call. */
11808 && type_dependent_expression_p_push (t)
11809 && !any_type_dependent_arguments_p (call_args))
11810 function = perform_koenig_lookup (function, call_args);
11812 if (TREE_CODE (function) == IDENTIFIER_NODE)
11814 unqualified_name_lookup_error (function);
11815 release_tree_vector (call_args);
11816 return error_mark_node;
11819 /* Remember that there was a reference to this entity. */
11820 if (DECL_P (function))
11821 mark_used (function);
11823 if (TREE_CODE (function) == OFFSET_REF)
11824 ret = build_offset_ref_call_from_tree (function, &call_args);
11825 else if (TREE_CODE (function) == COMPONENT_REF)
11827 if (!BASELINK_P (TREE_OPERAND (function, 1)))
11828 ret = finish_call_expr (function, &call_args,
11829 /*disallow_virtual=*/false,
11830 /*koenig_p=*/false,
11833 ret = (build_new_method_call
11834 (TREE_OPERAND (function, 0),
11835 TREE_OPERAND (function, 1),
11836 &call_args, NULL_TREE,
11837 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
11842 ret = finish_call_expr (function, &call_args,
11843 /*disallow_virtual=*/qualified_p,
11847 release_tree_vector (call_args);
11853 return build_x_conditional_expr
11854 (RECUR (TREE_OPERAND (t, 0)),
11855 RECUR (TREE_OPERAND (t, 1)),
11856 RECUR (TREE_OPERAND (t, 2)),
11859 case PSEUDO_DTOR_EXPR:
11860 return finish_pseudo_destructor_expr
11861 (RECUR (TREE_OPERAND (t, 0)),
11862 RECUR (TREE_OPERAND (t, 1)),
11863 RECUR (TREE_OPERAND (t, 2)));
11867 tree purpose, value, chain;
11869 if (t == void_list_node)
11872 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
11873 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
11875 /* We have pack expansions, so expand those and
11876 create a new list out of it. */
11877 tree purposevec = NULL_TREE;
11878 tree valuevec = NULL_TREE;
11882 /* Expand the argument expressions. */
11883 if (TREE_PURPOSE (t))
11884 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
11885 complain, in_decl);
11886 if (TREE_VALUE (t))
11887 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
11888 complain, in_decl);
11890 /* Build the rest of the list. */
11891 chain = TREE_CHAIN (t);
11892 if (chain && chain != void_type_node)
11893 chain = RECUR (chain);
11895 /* Determine the number of arguments. */
11896 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
11898 len = TREE_VEC_LENGTH (purposevec);
11899 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
11901 else if (TREE_CODE (valuevec) == TREE_VEC)
11902 len = TREE_VEC_LENGTH (valuevec);
11905 /* Since we only performed a partial substitution into
11906 the argument pack, we only return a single list
11908 if (purposevec == TREE_PURPOSE (t)
11909 && valuevec == TREE_VALUE (t)
11910 && chain == TREE_CHAIN (t))
11913 return tree_cons (purposevec, valuevec, chain);
11916 /* Convert the argument vectors into a TREE_LIST */
11920 /* Grab the Ith values. */
11922 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
11925 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
11928 /* Build the list (backwards). */
11929 chain = tree_cons (purpose, value, chain);
11935 purpose = TREE_PURPOSE (t);
11937 purpose = RECUR (purpose);
11938 value = TREE_VALUE (t);
11940 value = RECUR (value);
11941 chain = TREE_CHAIN (t);
11942 if (chain && chain != void_type_node)
11943 chain = RECUR (chain);
11944 if (purpose == TREE_PURPOSE (t)
11945 && value == TREE_VALUE (t)
11946 && chain == TREE_CHAIN (t))
11948 return tree_cons (purpose, value, chain);
11951 case COMPONENT_REF:
11957 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11958 args, complain, in_decl);
11959 /* Remember that there was a reference to this entity. */
11960 if (DECL_P (object))
11961 mark_used (object);
11962 object_type = TREE_TYPE (object);
11964 member = TREE_OPERAND (t, 1);
11965 if (BASELINK_P (member))
11966 member = tsubst_baselink (member,
11967 non_reference (TREE_TYPE (object)),
11968 args, complain, in_decl);
11970 member = tsubst_copy (member, args, complain, in_decl);
11971 if (member == error_mark_node)
11972 return error_mark_node;
11974 if (object_type && !CLASS_TYPE_P (object_type))
11976 if (SCALAR_TYPE_P (object_type))
11978 tree s = NULL_TREE;
11979 tree dtor = member;
11981 if (TREE_CODE (dtor) == SCOPE_REF)
11983 s = TREE_OPERAND (dtor, 0);
11984 dtor = TREE_OPERAND (dtor, 1);
11986 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
11988 dtor = TREE_OPERAND (dtor, 0);
11990 return finish_pseudo_destructor_expr (object, s, dtor);
11994 else if (TREE_CODE (member) == SCOPE_REF
11995 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
12000 /* Lookup the template functions now that we know what the
12002 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
12003 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
12004 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
12005 /*is_type_p=*/false,
12006 /*complain=*/false);
12007 if (BASELINK_P (member))
12009 BASELINK_FUNCTIONS (member)
12010 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
12012 member = (adjust_result_of_qualified_name_lookup
12013 (member, BINFO_TYPE (BASELINK_BINFO (member)),
12018 qualified_name_lookup_error (object_type, tmpl, member,
12020 return error_mark_node;
12023 else if (TREE_CODE (member) == SCOPE_REF
12024 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
12025 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
12027 if (complain & tf_error)
12029 if (TYPE_P (TREE_OPERAND (member, 0)))
12030 error ("%qT is not a class or namespace",
12031 TREE_OPERAND (member, 0));
12033 error ("%qD is not a class or namespace",
12034 TREE_OPERAND (member, 0));
12036 return error_mark_node;
12038 else if (TREE_CODE (member) == FIELD_DECL)
12039 return finish_non_static_data_member (member, object, NULL_TREE);
12041 return finish_class_member_access_expr (object, member,
12042 /*template_p=*/false,
12048 (RECUR (TREE_OPERAND (t, 0)));
12052 VEC(constructor_elt,gc) *n;
12053 constructor_elt *ce;
12054 unsigned HOST_WIDE_INT idx;
12055 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12056 bool process_index_p;
12058 bool need_copy_p = false;
12061 if (type == error_mark_node)
12062 return error_mark_node;
12064 /* digest_init will do the wrong thing if we let it. */
12065 if (type && TYPE_PTRMEMFUNC_P (type))
12068 /* We do not want to process the index of aggregate
12069 initializers as they are identifier nodes which will be
12070 looked up by digest_init. */
12071 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
12073 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
12074 newlen = VEC_length (constructor_elt, n);
12075 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
12077 if (ce->index && process_index_p)
12078 ce->index = RECUR (ce->index);
12080 if (PACK_EXPANSION_P (ce->value))
12082 /* Substitute into the pack expansion. */
12083 ce->value = tsubst_pack_expansion (ce->value, args, complain,
12086 if (ce->value == error_mark_node)
12088 else if (TREE_VEC_LENGTH (ce->value) == 1)
12089 /* Just move the argument into place. */
12090 ce->value = TREE_VEC_ELT (ce->value, 0);
12093 /* Update the length of the final CONSTRUCTOR
12094 arguments vector, and note that we will need to
12096 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
12097 need_copy_p = true;
12101 ce->value = RECUR (ce->value);
12106 VEC(constructor_elt,gc) *old_n = n;
12108 n = VEC_alloc (constructor_elt, gc, newlen);
12109 for (idx = 0; VEC_iterate (constructor_elt, old_n, idx, ce);
12112 if (TREE_CODE (ce->value) == TREE_VEC)
12114 int i, len = TREE_VEC_LENGTH (ce->value);
12115 for (i = 0; i < len; ++i)
12116 CONSTRUCTOR_APPEND_ELT (n, 0,
12117 TREE_VEC_ELT (ce->value, i));
12120 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
12124 r = build_constructor (init_list_type_node, n);
12125 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
12127 if (TREE_HAS_CONSTRUCTOR (t))
12128 return finish_compound_literal (type, r);
12135 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
12136 if (TYPE_P (operand_0))
12137 return get_typeid (operand_0);
12138 return build_typeid (operand_0);
12148 tree r = tsubst_copy (t, args, complain, in_decl);
12150 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
12151 /* If the original type was a reference, we'll be wrapped in
12152 the appropriate INDIRECT_REF. */
12153 r = convert_from_reference (r);
12158 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
12159 tsubst_copy (TREE_TYPE (t), args, complain,
12162 case OFFSETOF_EXPR:
12163 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
12167 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
12168 complain, in_decl);
12170 tree type2 = TRAIT_EXPR_TYPE2 (t);
12172 type2 = tsubst_copy (type2, args, complain, in_decl);
12174 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
12179 tree old_stmt_expr = cur_stmt_expr;
12180 tree stmt_expr = begin_stmt_expr ();
12182 cur_stmt_expr = stmt_expr;
12183 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
12184 integral_constant_expression_p);
12185 stmt_expr = finish_stmt_expr (stmt_expr, false);
12186 cur_stmt_expr = old_stmt_expr;
12192 t = tsubst_copy (t, args, complain, in_decl);
12193 /* As in finish_id_expression, we resolve enumeration constants
12194 to their underlying values. */
12195 if (TREE_CODE (t) == CONST_DECL)
12197 used_types_insert (TREE_TYPE (t));
12198 return DECL_INITIAL (t);
12203 /* Handle Objective-C++ constructs, if appropriate. */
12206 = objcp_tsubst_copy_and_build (t, args, complain,
12207 in_decl, /*function_p=*/false);
12211 return tsubst_copy (t, args, complain, in_decl);
12217 /* Verify that the instantiated ARGS are valid. For type arguments,
12218 make sure that the type is not variably modified. For non-type arguments,
12219 make sure they are constants if they are integral or enumerations.
12220 Emit an error under control of COMPLAIN, and return TRUE on error. */
12223 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
12225 if (ARGUMENT_PACK_P (t))
12227 tree vec = ARGUMENT_PACK_ARGS (t);
12228 int len = TREE_VEC_LENGTH (vec);
12229 bool result = false;
12232 for (i = 0; i < len; ++i)
12233 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
12237 else if (TYPE_P (t))
12239 if (variably_modified_type_p (t, NULL_TREE))
12241 if (complain & tf_error)
12242 error ("%qT is a variably modified type", t);
12246 /* A non-type argument of integral or enumerated type must be a
12248 else if (TREE_TYPE (t)
12249 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
12250 && !TREE_CONSTANT (t))
12252 if (complain & tf_error)
12253 error ("integral expression %qE is not constant", t);
12260 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
12262 int ix, len = DECL_NTPARMS (tmpl);
12263 bool result = false;
12265 for (ix = 0; ix != len; ix++)
12267 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
12270 if (result && (complain & tf_error))
12271 error (" trying to instantiate %qD", tmpl);
12275 /* Instantiate the indicated variable or function template TMPL with
12276 the template arguments in TARG_PTR. */
12279 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
12281 tree targ_ptr = orig_args;
12285 HOST_WIDE_INT saved_processing_template_decl;
12287 if (tmpl == error_mark_node)
12288 return error_mark_node;
12290 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
12292 /* If this function is a clone, handle it specially. */
12293 if (DECL_CLONED_FUNCTION_P (tmpl))
12298 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
12299 DECL_CLONED_FUNCTION. */
12300 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
12301 targ_ptr, complain);
12302 if (spec == error_mark_node)
12303 return error_mark_node;
12305 /* Look for the clone. */
12306 FOR_EACH_CLONE (clone, spec)
12307 if (DECL_NAME (clone) == DECL_NAME (tmpl))
12309 /* We should always have found the clone by now. */
12310 gcc_unreachable ();
12314 /* Check to see if we already have this specialization. */
12315 gen_tmpl = most_general_template (tmpl);
12316 if (tmpl != gen_tmpl)
12317 /* The TMPL is a partial instantiation. To get a full set of
12318 arguments we must add the arguments used to perform the
12319 partial instantiation. */
12320 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
12323 /* It would be nice to avoid hashing here and then again in tsubst_decl,
12324 but it doesn't seem to be on the hot path. */
12325 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
12327 gcc_assert (tmpl == gen_tmpl
12328 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
12330 || fndecl == NULL_TREE);
12332 if (spec != NULL_TREE)
12335 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
12337 return error_mark_node;
12339 /* We are building a FUNCTION_DECL, during which the access of its
12340 parameters and return types have to be checked. However this
12341 FUNCTION_DECL which is the desired context for access checking
12342 is not built yet. We solve this chicken-and-egg problem by
12343 deferring all checks until we have the FUNCTION_DECL. */
12344 push_deferring_access_checks (dk_deferred);
12346 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
12347 (because, for example, we have encountered a non-dependent
12348 function call in the body of a template function and must now
12349 determine which of several overloaded functions will be called),
12350 within the instantiation itself we are not processing a
12352 saved_processing_template_decl = processing_template_decl;
12353 processing_template_decl = 0;
12354 /* Substitute template parameters to obtain the specialization. */
12355 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
12356 targ_ptr, complain, gen_tmpl);
12357 processing_template_decl = saved_processing_template_decl;
12358 if (fndecl == error_mark_node)
12359 return error_mark_node;
12361 /* Now we know the specialization, compute access previously
12363 push_access_scope (fndecl);
12365 /* Some typedefs referenced from within the template code need to be access
12366 checked at template instantiation time, i.e now. These types were
12367 added to the template at parsing time. Let's get those and perfom
12368 the acces checks then. */
12369 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
12370 perform_deferred_access_checks ();
12371 pop_access_scope (fndecl);
12372 pop_deferring_access_checks ();
12374 /* The DECL_TI_TEMPLATE should always be the immediate parent
12375 template, not the most general template. */
12376 DECL_TI_TEMPLATE (fndecl) = tmpl;
12378 /* If we've just instantiated the main entry point for a function,
12379 instantiate all the alternate entry points as well. We do this
12380 by cloning the instantiation of the main entry point, not by
12381 instantiating the template clones. */
12382 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
12383 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
12388 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
12389 NARGS elements of the arguments that are being used when calling
12390 it. TARGS is a vector into which the deduced template arguments
12393 Return zero for success, 2 for an incomplete match that doesn't resolve
12394 all the types, and 1 for complete failure. An error message will be
12395 printed only for an incomplete match.
12397 If FN is a conversion operator, or we are trying to produce a specific
12398 specialization, RETURN_TYPE is the return type desired.
12400 The EXPLICIT_TARGS are explicit template arguments provided via a
12403 The parameter STRICT is one of:
12406 We are deducing arguments for a function call, as in
12407 [temp.deduct.call].
12410 We are deducing arguments for a conversion function, as in
12411 [temp.deduct.conv].
12414 We are deducing arguments when doing an explicit instantiation
12415 as in [temp.explicit], when determining an explicit specialization
12416 as in [temp.expl.spec], or when taking the address of a function
12417 template, as in [temp.deduct.funcaddr]. */
12420 fn_type_unification (tree fn,
12421 tree explicit_targs,
12424 unsigned int nargs,
12426 unification_kind_t strict,
12432 bool incomplete_argument_packs_p = false;
12434 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
12436 fntype = TREE_TYPE (fn);
12437 if (explicit_targs)
12441 The specified template arguments must match the template
12442 parameters in kind (i.e., type, nontype, template), and there
12443 must not be more arguments than there are parameters;
12444 otherwise type deduction fails.
12446 Nontype arguments must match the types of the corresponding
12447 nontype template parameters, or must be convertible to the
12448 types of the corresponding nontype parameters as specified in
12449 _temp.arg.nontype_, otherwise type deduction fails.
12451 All references in the function type of the function template
12452 to the corresponding template parameters are replaced by the
12453 specified template argument values. If a substitution in a
12454 template parameter or in the function type of the function
12455 template results in an invalid type, type deduction fails. */
12456 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
12457 int i, len = TREE_VEC_LENGTH (tparms);
12458 tree converted_args;
12459 bool incomplete = false;
12461 if (explicit_targs == error_mark_node)
12465 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
12466 /*require_all_args=*/false,
12467 /*use_default_args=*/false));
12468 if (converted_args == error_mark_node)
12471 /* Substitute the explicit args into the function type. This is
12472 necessary so that, for instance, explicitly declared function
12473 arguments can match null pointed constants. If we were given
12474 an incomplete set of explicit args, we must not do semantic
12475 processing during substitution as we could create partial
12477 for (i = 0; i < len; i++)
12479 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
12480 bool parameter_pack = false;
12482 /* Dig out the actual parm. */
12483 if (TREE_CODE (parm) == TYPE_DECL
12484 || TREE_CODE (parm) == TEMPLATE_DECL)
12486 parm = TREE_TYPE (parm);
12487 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
12489 else if (TREE_CODE (parm) == PARM_DECL)
12491 parm = DECL_INITIAL (parm);
12492 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
12495 if (parameter_pack)
12499 template_parm_level_and_index (parm, &level, &idx);
12501 /* Mark the argument pack as "incomplete". We could
12502 still deduce more arguments during unification. */
12503 targ = TMPL_ARG (converted_args, level, idx);
12506 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
12507 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
12508 = ARGUMENT_PACK_ARGS (targ);
12511 /* We have some incomplete argument packs. */
12512 incomplete_argument_packs_p = true;
12516 if (incomplete_argument_packs_p)
12517 /* Any substitution is guaranteed to be incomplete if there
12518 are incomplete argument packs, because we can still deduce
12522 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
12524 processing_template_decl += incomplete;
12525 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
12526 processing_template_decl -= incomplete;
12528 if (fntype == error_mark_node)
12531 /* Place the explicitly specified arguments in TARGS. */
12532 for (i = NUM_TMPL_ARGS (converted_args); i--;)
12533 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
12536 /* Never do unification on the 'this' parameter. */
12537 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
12543 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
12544 new_args = XALLOCAVEC (tree, nargs + 1);
12545 new_args[0] = return_type;
12546 memcpy (new_args + 1, args, nargs * sizeof (tree));
12551 /* We allow incomplete unification without an error message here
12552 because the standard doesn't seem to explicitly prohibit it. Our
12553 callers must be ready to deal with unification failures in any
12555 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
12556 targs, parms, args, nargs, /*subr=*/0,
12559 if (result == 0 && incomplete_argument_packs_p)
12561 int i, len = NUM_TMPL_ARGS (targs);
12563 /* Clear the "incomplete" flags on all argument packs. */
12564 for (i = 0; i < len; i++)
12566 tree arg = TREE_VEC_ELT (targs, i);
12567 if (ARGUMENT_PACK_P (arg))
12569 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
12570 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
12575 /* Now that we have bindings for all of the template arguments,
12576 ensure that the arguments deduced for the template template
12577 parameters have compatible template parameter lists. We cannot
12578 check this property before we have deduced all template
12579 arguments, because the template parameter types of a template
12580 template parameter might depend on prior template parameters
12581 deduced after the template template parameter. The following
12582 ill-formed example illustrates this issue:
12584 template<typename T, template<T> class C> void f(C<5>, T);
12586 template<int N> struct X {};
12589 f(X<5>(), 5l); // error: template argument deduction fails
12592 The template parameter list of 'C' depends on the template type
12593 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
12594 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
12595 time that we deduce 'C'. */
12597 && !template_template_parm_bindings_ok_p
12598 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
12602 /* All is well so far. Now, check:
12606 When all template arguments have been deduced, all uses of
12607 template parameters in nondeduced contexts are replaced with
12608 the corresponding deduced argument values. If the
12609 substitution results in an invalid type, as described above,
12610 type deduction fails. */
12612 tree substed = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE);
12613 if (substed == error_mark_node)
12616 /* If we're looking for an exact match, check that what we got
12617 is indeed an exact match. It might not be if some template
12618 parameters are used in non-deduced contexts. */
12619 if (strict == DEDUCE_EXACT)
12624 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
12626 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
12627 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
12628 if (!same_type_p (args[i], TREE_VALUE (sarg)))
12636 /* Adjust types before performing type deduction, as described in
12637 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
12638 sections are symmetric. PARM is the type of a function parameter
12639 or the return type of the conversion function. ARG is the type of
12640 the argument passed to the call, or the type of the value
12641 initialized with the result of the conversion function.
12642 ARG_EXPR is the original argument expression, which may be null. */
12645 maybe_adjust_types_for_deduction (unification_kind_t strict,
12659 /* Swap PARM and ARG throughout the remainder of this
12660 function; the handling is precisely symmetric since PARM
12661 will initialize ARG rather than vice versa. */
12669 /* There is nothing to do in this case. */
12673 gcc_unreachable ();
12676 if (TREE_CODE (*parm) != REFERENCE_TYPE)
12678 /* [temp.deduct.call]
12680 If P is not a reference type:
12682 --If A is an array type, the pointer type produced by the
12683 array-to-pointer standard conversion (_conv.array_) is
12684 used in place of A for type deduction; otherwise,
12686 --If A is a function type, the pointer type produced by
12687 the function-to-pointer standard conversion
12688 (_conv.func_) is used in place of A for type deduction;
12691 --If A is a cv-qualified type, the top level
12692 cv-qualifiers of A's type are ignored for type
12694 if (TREE_CODE (*arg) == ARRAY_TYPE)
12695 *arg = build_pointer_type (TREE_TYPE (*arg));
12696 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
12697 *arg = build_pointer_type (*arg);
12699 *arg = TYPE_MAIN_VARIANT (*arg);
12702 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
12703 of the form T&&, where T is a template parameter, and the argument
12704 is an lvalue, T is deduced as A& */
12705 if (TREE_CODE (*parm) == REFERENCE_TYPE
12706 && TYPE_REF_IS_RVALUE (*parm)
12707 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
12708 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
12709 && arg_expr && real_lvalue_p (arg_expr))
12710 *arg = build_reference_type (*arg);
12712 /* [temp.deduct.call]
12714 If P is a cv-qualified type, the top level cv-qualifiers
12715 of P's type are ignored for type deduction. If P is a
12716 reference type, the type referred to by P is used for
12718 *parm = TYPE_MAIN_VARIANT (*parm);
12719 if (TREE_CODE (*parm) == REFERENCE_TYPE)
12721 *parm = TREE_TYPE (*parm);
12722 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
12725 /* DR 322. For conversion deduction, remove a reference type on parm
12726 too (which has been swapped into ARG). */
12727 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
12728 *arg = TREE_TYPE (*arg);
12733 /* Most parms like fn_type_unification.
12735 If SUBR is 1, we're being called recursively (to unify the
12736 arguments of a function or method parameter of a function
12740 type_unification_real (tree tparms,
12744 unsigned int xnargs,
12746 unification_kind_t strict,
12749 tree parm, arg, arg_expr;
12751 int ntparms = TREE_VEC_LENGTH (tparms);
12753 int saw_undeduced = 0;
12756 unsigned int nargs;
12759 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
12760 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
12761 gcc_assert (ntparms > 0);
12766 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
12767 | UNIFY_ALLOW_DERIVED);
12771 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
12775 sub_strict = UNIFY_ALLOW_NONE;
12779 gcc_unreachable ();
12788 while (parms && parms != void_list_node
12791 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
12794 parm = TREE_VALUE (parms);
12795 parms = TREE_CHAIN (parms);
12800 if (arg == error_mark_node)
12802 if (arg == unknown_type_node)
12803 /* We can't deduce anything from this, but we might get all the
12804 template args from other function args. */
12807 /* Conversions will be performed on a function argument that
12808 corresponds with a function parameter that contains only
12809 non-deducible template parameters and explicitly specified
12810 template parameters. */
12811 if (!uses_template_parms (parm))
12816 type = TREE_TYPE (arg);
12820 if (same_type_p (parm, type))
12822 if (strict != DEDUCE_EXACT
12823 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
12832 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
12833 if (type_unknown_p (arg))
12835 /* [temp.deduct.type]
12837 A template-argument can be deduced from a pointer to
12838 function or pointer to member function argument if
12839 the set of overloaded functions does not contain
12840 function templates and at most one of a set of
12841 overloaded functions provides a unique match. */
12842 if (resolve_overloaded_unification
12843 (tparms, targs, parm, arg, strict, sub_strict))
12849 arg = unlowered_expr_type (arg);
12850 if (arg == error_mark_node)
12855 int arg_strict = sub_strict;
12858 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
12861 if (arg == init_list_type_node && arg_expr)
12863 if (unify (tparms, targs, parm, arg, arg_strict))
12870 && parms != void_list_node
12871 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
12873 /* Unify the remaining arguments with the pack expansion type. */
12875 tree parmvec = make_tree_vec (1);
12877 /* Allocate a TREE_VEC and copy in all of the arguments */
12878 argvec = make_tree_vec (nargs - ia);
12879 for (i = 0; ia < nargs; ++ia, ++i)
12880 TREE_VEC_ELT (argvec, i) = args[ia];
12882 /* Copy the parameter into parmvec. */
12883 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
12884 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
12885 /*call_args_p=*/true, /*subr=*/subr))
12888 /* Advance to the end of the list of parameters. */
12889 parms = TREE_CHAIN (parms);
12892 /* Fail if we've reached the end of the parm list, and more args
12893 are present, and the parm list isn't variadic. */
12894 if (ia < nargs && parms == void_list_node)
12896 /* Fail if parms are left and they don't have default values. */
12897 if (parms && parms != void_list_node
12898 && TREE_PURPOSE (parms) == NULL_TREE)
12902 for (i = 0; i < ntparms; i++)
12903 if (!TREE_VEC_ELT (targs, i))
12907 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
12910 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
12912 /* If this is an undeduced nontype parameter that depends on
12913 a type parameter, try another pass; its type may have been
12914 deduced from a later argument than the one from which
12915 this parameter can be deduced. */
12916 if (TREE_CODE (tparm) == PARM_DECL
12917 && uses_template_parms (TREE_TYPE (tparm))
12918 && !saw_undeduced++)
12921 /* Core issue #226 (C++0x) [temp.deduct]:
12923 If a template argument has not been deduced, its
12924 default template argument, if any, is used.
12926 When we are in C++98 mode, TREE_PURPOSE will either
12927 be NULL_TREE or ERROR_MARK_NODE, so we do not need
12928 to explicitly check cxx_dialect here. */
12929 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
12931 tree arg = tsubst_template_arg
12932 (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)),
12933 targs, tf_none, NULL_TREE);
12934 if (arg == error_mark_node)
12938 TREE_VEC_ELT (targs, i) = arg;
12943 /* If the type parameter is a parameter pack, then it will
12944 be deduced to an empty parameter pack. */
12945 if (template_parameter_pack_p (tparm))
12949 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
12951 arg = make_node (NONTYPE_ARGUMENT_PACK);
12952 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
12953 TREE_CONSTANT (arg) = 1;
12956 arg = make_node (TYPE_ARGUMENT_PACK);
12958 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
12960 TREE_VEC_ELT (targs, i) = arg;
12970 /* Subroutine of type_unification_real. Args are like the variables
12971 at the call site. ARG is an overloaded function (or template-id);
12972 we try deducing template args from each of the overloads, and if
12973 only one succeeds, we go with that. Modifies TARGS and returns
12974 true on success. */
12977 resolve_overloaded_unification (tree tparms,
12981 unification_kind_t strict,
12984 tree tempargs = copy_node (targs);
12986 tree goodfn = NULL_TREE;
12989 if (TREE_CODE (arg) == ADDR_EXPR)
12991 arg = TREE_OPERAND (arg, 0);
12997 if (TREE_CODE (arg) == COMPONENT_REF)
12998 /* Handle `&x' where `x' is some static or non-static member
13000 arg = TREE_OPERAND (arg, 1);
13002 if (TREE_CODE (arg) == OFFSET_REF)
13003 arg = TREE_OPERAND (arg, 1);
13005 /* Strip baselink information. */
13006 if (BASELINK_P (arg))
13007 arg = BASELINK_FUNCTIONS (arg);
13009 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
13011 /* If we got some explicit template args, we need to plug them into
13012 the affected templates before we try to unify, in case the
13013 explicit args will completely resolve the templates in question. */
13015 tree expl_subargs = TREE_OPERAND (arg, 1);
13016 arg = TREE_OPERAND (arg, 0);
13018 for (; arg; arg = OVL_NEXT (arg))
13020 tree fn = OVL_CURRENT (arg);
13021 tree subargs, elem;
13023 if (TREE_CODE (fn) != TEMPLATE_DECL)
13026 ++processing_template_decl;
13027 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13028 expl_subargs, /*check_ret=*/false);
13031 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
13032 if (try_one_overload (tparms, targs, tempargs, parm,
13033 elem, strict, sub_strict, addr_p)
13034 && (!goodfn || !decls_match (goodfn, elem)))
13040 --processing_template_decl;
13043 else if (TREE_CODE (arg) != OVERLOAD
13044 && TREE_CODE (arg) != FUNCTION_DECL)
13045 /* If ARG is, for example, "(0, &f)" then its type will be unknown
13046 -- but the deduction does not succeed because the expression is
13047 not just the function on its own. */
13050 for (; arg; arg = OVL_NEXT (arg))
13051 if (try_one_overload (tparms, targs, tempargs, parm,
13052 TREE_TYPE (OVL_CURRENT (arg)),
13053 strict, sub_strict, addr_p)
13054 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
13056 goodfn = OVL_CURRENT (arg);
13060 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13061 to function or pointer to member function argument if the set of
13062 overloaded functions does not contain function templates and at most
13063 one of a set of overloaded functions provides a unique match.
13065 So if we found multiple possibilities, we return success but don't
13066 deduce anything. */
13070 int i = TREE_VEC_LENGTH (targs);
13072 if (TREE_VEC_ELT (tempargs, i))
13073 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
13081 /* Subroutine of resolve_overloaded_unification; does deduction for a single
13082 overload. Fills TARGS with any deduced arguments, or error_mark_node if
13083 different overloads deduce different arguments for a given parm.
13084 ADDR_P is true if the expression for which deduction is being
13085 performed was of the form "& fn" rather than simply "fn".
13087 Returns 1 on success. */
13090 try_one_overload (tree tparms,
13095 unification_kind_t strict,
13103 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13104 to function or pointer to member function argument if the set of
13105 overloaded functions does not contain function templates and at most
13106 one of a set of overloaded functions provides a unique match.
13108 So if this is a template, just return success. */
13110 if (uses_template_parms (arg))
13113 if (TREE_CODE (arg) == METHOD_TYPE)
13114 arg = build_ptrmemfunc_type (build_pointer_type (arg));
13116 arg = build_pointer_type (arg);
13118 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
13120 /* We don't copy orig_targs for this because if we have already deduced
13121 some template args from previous args, unify would complain when we
13122 try to deduce a template parameter for the same argument, even though
13123 there isn't really a conflict. */
13124 nargs = TREE_VEC_LENGTH (targs);
13125 tempargs = make_tree_vec (nargs);
13127 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
13130 /* First make sure we didn't deduce anything that conflicts with
13131 explicitly specified args. */
13132 for (i = nargs; i--; )
13134 tree elt = TREE_VEC_ELT (tempargs, i);
13135 tree oldelt = TREE_VEC_ELT (orig_targs, i);
13139 else if (uses_template_parms (elt))
13140 /* Since we're unifying against ourselves, we will fill in
13141 template args used in the function parm list with our own
13142 template parms. Discard them. */
13143 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
13144 else if (oldelt && !template_args_equal (oldelt, elt))
13148 for (i = nargs; i--; )
13150 tree elt = TREE_VEC_ELT (tempargs, i);
13153 TREE_VEC_ELT (targs, i) = elt;
13159 /* PARM is a template class (perhaps with unbound template
13160 parameters). ARG is a fully instantiated type. If ARG can be
13161 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
13162 TARGS are as for unify. */
13165 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
13167 tree copy_of_targs;
13169 if (!CLASSTYPE_TEMPLATE_INFO (arg)
13170 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
13171 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
13174 /* We need to make a new template argument vector for the call to
13175 unify. If we used TARGS, we'd clutter it up with the result of
13176 the attempted unification, even if this class didn't work out.
13177 We also don't want to commit ourselves to all the unifications
13178 we've already done, since unification is supposed to be done on
13179 an argument-by-argument basis. In other words, consider the
13180 following pathological case:
13182 template <int I, int J, int K>
13185 template <int I, int J>
13186 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
13188 template <int I, int J, int K>
13189 void f(S<I, J, K>, S<I, I, I>);
13198 Now, by the time we consider the unification involving `s2', we
13199 already know that we must have `f<0, 0, 0>'. But, even though
13200 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
13201 because there are two ways to unify base classes of S<0, 1, 2>
13202 with S<I, I, I>. If we kept the already deduced knowledge, we
13203 would reject the possibility I=1. */
13204 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
13206 /* If unification failed, we're done. */
13207 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
13208 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
13214 /* Given a template type PARM and a class type ARG, find the unique
13215 base type in ARG that is an instance of PARM. We do not examine
13216 ARG itself; only its base-classes. If there is not exactly one
13217 appropriate base class, return NULL_TREE. PARM may be the type of
13218 a partial specialization, as well as a plain template type. Used
13222 get_template_base (tree tparms, tree targs, tree parm, tree arg)
13224 tree rval = NULL_TREE;
13227 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
13229 binfo = TYPE_BINFO (complete_type (arg));
13231 /* The type could not be completed. */
13234 /* Walk in inheritance graph order. The search order is not
13235 important, and this avoids multiple walks of virtual bases. */
13236 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
13238 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
13242 /* If there is more than one satisfactory baseclass, then:
13246 If they yield more than one possible deduced A, the type
13250 if (rval && !same_type_p (r, rval))
13260 /* Returns the level of DECL, which declares a template parameter. */
13263 template_decl_level (tree decl)
13265 switch (TREE_CODE (decl))
13268 case TEMPLATE_DECL:
13269 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
13272 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
13275 gcc_unreachable ();
13280 /* Decide whether ARG can be unified with PARM, considering only the
13281 cv-qualifiers of each type, given STRICT as documented for unify.
13282 Returns nonzero iff the unification is OK on that basis. */
13285 check_cv_quals_for_unify (int strict, tree arg, tree parm)
13287 int arg_quals = cp_type_quals (arg);
13288 int parm_quals = cp_type_quals (parm);
13290 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13291 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
13293 /* Although a CVR qualifier is ignored when being applied to a
13294 substituted template parameter ([8.3.2]/1 for example), that
13295 does not apply during deduction [14.8.2.4]/1, (even though
13296 that is not explicitly mentioned, [14.8.2.4]/9 indicates
13297 this). Except when we're allowing additional CV qualifiers
13298 at the outer level [14.8.2.1]/3,1st bullet. */
13299 if ((TREE_CODE (arg) == REFERENCE_TYPE
13300 || TREE_CODE (arg) == FUNCTION_TYPE
13301 || TREE_CODE (arg) == METHOD_TYPE)
13302 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
13305 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
13306 && (parm_quals & TYPE_QUAL_RESTRICT))
13310 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
13311 && (arg_quals & parm_quals) != parm_quals)
13314 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
13315 && (parm_quals & arg_quals) != arg_quals)
13321 /* Determines the LEVEL and INDEX for the template parameter PARM. */
13323 template_parm_level_and_index (tree parm, int* level, int* index)
13325 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13326 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13327 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13329 *index = TEMPLATE_TYPE_IDX (parm);
13330 *level = TEMPLATE_TYPE_LEVEL (parm);
13334 *index = TEMPLATE_PARM_IDX (parm);
13335 *level = TEMPLATE_PARM_LEVEL (parm);
13339 /* Unifies the remaining arguments in PACKED_ARGS with the pack
13340 expansion at the end of PACKED_PARMS. Returns 0 if the type
13341 deduction succeeds, 1 otherwise. STRICT is the same as in
13342 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
13343 call argument list. We'll need to adjust the arguments to make them
13344 types. SUBR tells us if this is from a recursive call to
13345 type_unification_real. */
13347 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
13348 tree packed_args, int strict, bool call_args_p,
13352 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
13353 tree pattern = PACK_EXPANSION_PATTERN (parm);
13354 tree pack, packs = NULL_TREE;
13355 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
13356 int len = TREE_VEC_LENGTH (packed_args);
13358 /* Determine the parameter packs we will be deducing from the
13359 pattern, and record their current deductions. */
13360 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
13361 pack; pack = TREE_CHAIN (pack))
13363 tree parm_pack = TREE_VALUE (pack);
13366 /* Determine the index and level of this parameter pack. */
13367 template_parm_level_and_index (parm_pack, &level, &idx);
13369 /* Keep track of the parameter packs and their corresponding
13371 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
13372 TREE_TYPE (packs) = make_tree_vec (len - start);
13375 /* Loop through all of the arguments that have not yet been
13376 unified and unify each with the pattern. */
13377 for (i = start; i < len; i++)
13379 tree parm = pattern;
13381 /* For each parameter pack, clear out the deduced value so that
13382 we can deduce it again. */
13383 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13386 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13388 TMPL_ARG (targs, level, idx) = NULL_TREE;
13391 /* Unify the pattern with the current argument. */
13393 tree arg = TREE_VEC_ELT (packed_args, i);
13394 tree arg_expr = NULL_TREE;
13395 int arg_strict = strict;
13396 bool skip_arg_p = false;
13402 /* This mirrors what we do in type_unification_real. */
13406 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
13407 | UNIFY_ALLOW_MORE_CV_QUAL
13408 | UNIFY_ALLOW_DERIVED);
13412 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
13416 sub_strict = UNIFY_ALLOW_NONE;
13420 gcc_unreachable ();
13425 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
13426 if (type_unknown_p (arg))
13428 /* [temp.deduct.type] A template-argument can be
13429 deduced from a pointer to function or pointer
13430 to member function argument if the set of
13431 overloaded functions does not contain function
13432 templates and at most one of a set of
13433 overloaded functions provides a unique
13436 if (resolve_overloaded_unification
13437 (tparms, targs, parm, arg,
13438 (unification_kind_t) strict,
13448 arg = unlowered_expr_type (arg);
13449 if (arg == error_mark_node)
13454 arg_strict = sub_strict;
13458 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
13459 &parm, &arg, arg_expr);
13464 if (unify (tparms, targs, parm, arg, arg_strict))
13469 /* For each parameter pack, collect the deduced value. */
13470 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13473 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13475 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
13476 TMPL_ARG (targs, level, idx);
13480 /* Verify that the results of unification with the parameter packs
13481 produce results consistent with what we've seen before, and make
13482 the deduced argument packs available. */
13483 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13485 tree old_pack = TREE_VALUE (pack);
13486 tree new_args = TREE_TYPE (pack);
13487 int i, len = TREE_VEC_LENGTH (new_args);
13488 bool nondeduced_p = false;
13490 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
13491 actually deduce anything. */
13492 for (i = 0; i < len && !nondeduced_p; ++i)
13493 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
13494 nondeduced_p = true;
13498 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
13500 /* Prepend the explicit arguments onto NEW_ARGS. */
13501 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
13502 tree old_args = new_args;
13503 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
13504 int len = explicit_len + TREE_VEC_LENGTH (old_args);
13506 /* Copy the explicit arguments. */
13507 new_args = make_tree_vec (len);
13508 for (i = 0; i < explicit_len; i++)
13509 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
13511 /* Copy the deduced arguments. */
13512 for (; i < len; i++)
13513 TREE_VEC_ELT (new_args, i) =
13514 TREE_VEC_ELT (old_args, i - explicit_len);
13522 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13524 /* Build the deduced *_ARGUMENT_PACK. */
13525 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
13527 result = make_node (NONTYPE_ARGUMENT_PACK);
13528 TREE_TYPE (result) =
13529 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
13530 TREE_CONSTANT (result) = 1;
13533 result = make_node (TYPE_ARGUMENT_PACK);
13535 SET_ARGUMENT_PACK_ARGS (result, new_args);
13537 /* Note the deduced argument packs for this parameter
13539 TMPL_ARG (targs, level, idx) = result;
13541 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
13542 && (ARGUMENT_PACK_ARGS (old_pack)
13543 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
13545 /* We only had the explicitly-provided arguments before, but
13546 now we have a complete set of arguments. */
13548 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
13549 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13551 /* Keep the original deduced argument pack. */
13552 TMPL_ARG (targs, level, idx) = old_pack;
13554 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
13555 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
13556 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
13558 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
13560 /* Inconsistent unification of this parameter pack. */
13566 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13568 /* Keep the original deduced argument pack. */
13569 TMPL_ARG (targs, level, idx) = old_pack;
13576 /* Deduce the value of template parameters. TPARMS is the (innermost)
13577 set of template parameters to a template. TARGS is the bindings
13578 for those template parameters, as determined thus far; TARGS may
13579 include template arguments for outer levels of template parameters
13580 as well. PARM is a parameter to a template function, or a
13581 subcomponent of that parameter; ARG is the corresponding argument.
13582 This function attempts to match PARM with ARG in a manner
13583 consistent with the existing assignments in TARGS. If more values
13584 are deduced, then TARGS is updated.
13586 Returns 0 if the type deduction succeeds, 1 otherwise. The
13587 parameter STRICT is a bitwise or of the following flags:
13590 Require an exact match between PARM and ARG.
13591 UNIFY_ALLOW_MORE_CV_QUAL:
13592 Allow the deduced ARG to be more cv-qualified (by qualification
13593 conversion) than ARG.
13594 UNIFY_ALLOW_LESS_CV_QUAL:
13595 Allow the deduced ARG to be less cv-qualified than ARG.
13596 UNIFY_ALLOW_DERIVED:
13597 Allow the deduced ARG to be a template base class of ARG,
13598 or a pointer to a template base class of the type pointed to by
13600 UNIFY_ALLOW_INTEGER:
13601 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
13602 case for more information.
13603 UNIFY_ALLOW_OUTER_LEVEL:
13604 This is the outermost level of a deduction. Used to determine validity
13605 of qualification conversions. A valid qualification conversion must
13606 have const qualified pointers leading up to the inner type which
13607 requires additional CV quals, except at the outer level, where const
13608 is not required [conv.qual]. It would be normal to set this flag in
13609 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
13610 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
13611 This is the outermost level of a deduction, and PARM can be more CV
13612 qualified at this point.
13613 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
13614 This is the outermost level of a deduction, and PARM can be less CV
13615 qualified at this point. */
13618 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
13623 int strict_in = strict;
13625 /* I don't think this will do the right thing with respect to types.
13626 But the only case I've seen it in so far has been array bounds, where
13627 signedness is the only information lost, and I think that will be
13629 while (TREE_CODE (parm) == NOP_EXPR)
13630 parm = TREE_OPERAND (parm, 0);
13632 if (arg == error_mark_node)
13634 if (arg == unknown_type_node
13635 || arg == init_list_type_node)
13636 /* We can't deduce anything from this, but we might get all the
13637 template args from other function args. */
13640 /* If PARM uses template parameters, then we can't bail out here,
13641 even if ARG == PARM, since we won't record unifications for the
13642 template parameters. We might need them if we're trying to
13643 figure out which of two things is more specialized. */
13644 if (arg == parm && !uses_template_parms (parm))
13647 /* Handle init lists early, so the rest of the function can assume
13648 we're dealing with a type. */
13649 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
13654 if (!is_std_init_list (parm))
13655 /* We can only deduce from an initializer list argument if the
13656 parameter is std::initializer_list; otherwise this is a
13657 non-deduced context. */
13660 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
13662 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
13664 int elt_strict = strict;
13665 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
13667 tree type = TREE_TYPE (elt);
13668 /* It should only be possible to get here for a call. */
13669 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
13670 elt_strict |= maybe_adjust_types_for_deduction
13671 (DEDUCE_CALL, &elttype, &type, elt);
13675 if (unify (tparms, targs, elttype, elt, elt_strict))
13681 /* Immediately reject some pairs that won't unify because of
13682 cv-qualification mismatches. */
13683 if (TREE_CODE (arg) == TREE_CODE (parm)
13685 /* It is the elements of the array which hold the cv quals of an array
13686 type, and the elements might be template type parms. We'll check
13687 when we recurse. */
13688 && TREE_CODE (arg) != ARRAY_TYPE
13689 /* We check the cv-qualifiers when unifying with template type
13690 parameters below. We want to allow ARG `const T' to unify with
13691 PARM `T' for example, when computing which of two templates
13692 is more specialized, for example. */
13693 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
13694 && !check_cv_quals_for_unify (strict_in, arg, parm))
13697 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
13698 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
13699 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
13700 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
13701 strict &= ~UNIFY_ALLOW_DERIVED;
13702 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
13703 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
13705 switch (TREE_CODE (parm))
13707 case TYPENAME_TYPE:
13709 case UNBOUND_CLASS_TEMPLATE:
13710 /* In a type which contains a nested-name-specifier, template
13711 argument values cannot be deduced for template parameters used
13712 within the nested-name-specifier. */
13715 case TEMPLATE_TYPE_PARM:
13716 case TEMPLATE_TEMPLATE_PARM:
13717 case BOUND_TEMPLATE_TEMPLATE_PARM:
13718 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
13719 if (tparm == error_mark_node)
13722 if (TEMPLATE_TYPE_LEVEL (parm)
13723 != template_decl_level (tparm))
13724 /* The PARM is not one we're trying to unify. Just check
13725 to see if it matches ARG. */
13726 return (TREE_CODE (arg) == TREE_CODE (parm)
13727 && same_type_p (parm, arg)) ? 0 : 1;
13728 idx = TEMPLATE_TYPE_IDX (parm);
13729 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
13730 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
13732 /* Check for mixed types and values. */
13733 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13734 && TREE_CODE (tparm) != TYPE_DECL)
13735 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13736 && TREE_CODE (tparm) != TEMPLATE_DECL))
13739 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13741 /* ARG must be constructed from a template class or a template
13742 template parameter. */
13743 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
13744 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
13748 tree parmvec = TYPE_TI_ARGS (parm);
13749 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
13751 = DECL_INNERMOST_TEMPLATE_PARMS
13752 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
13754 int parm_variadic_p = 0;
13756 /* The resolution to DR150 makes clear that default
13757 arguments for an N-argument may not be used to bind T
13758 to a template template parameter with fewer than N
13759 parameters. It is not safe to permit the binding of
13760 default arguments as an extension, as that may change
13761 the meaning of a conforming program. Consider:
13763 struct Dense { static const unsigned int dim = 1; };
13765 template <template <typename> class View,
13767 void operator+(float, View<Block> const&);
13769 template <typename Block,
13770 unsigned int Dim = Block::dim>
13771 struct Lvalue_proxy { operator float() const; };
13775 Lvalue_proxy<Dense> p;
13780 Here, if Lvalue_proxy is permitted to bind to View, then
13781 the global operator+ will be used; if they are not, the
13782 Lvalue_proxy will be converted to float. */
13783 if (coerce_template_parms (parm_parms,
13785 TYPE_TI_TEMPLATE (parm),
13787 /*require_all_args=*/true,
13788 /*use_default_args=*/false)
13789 == error_mark_node)
13792 /* Deduce arguments T, i from TT<T> or TT<i>.
13793 We check each element of PARMVEC and ARGVEC individually
13794 rather than the whole TREE_VEC since they can have
13795 different number of elements. */
13797 parmvec = expand_template_argument_pack (parmvec);
13798 argvec = expand_template_argument_pack (argvec);
13800 len = TREE_VEC_LENGTH (parmvec);
13802 /* Check if the parameters end in a pack, making them
13805 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
13806 parm_variadic_p = 1;
13808 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
13811 for (i = 0; i < len - parm_variadic_p; ++i)
13813 if (unify (tparms, targs,
13814 TREE_VEC_ELT (parmvec, i),
13815 TREE_VEC_ELT (argvec, i),
13820 if (parm_variadic_p
13821 && unify_pack_expansion (tparms, targs,
13824 /*call_args_p=*/false,
13828 arg = TYPE_TI_TEMPLATE (arg);
13830 /* Fall through to deduce template name. */
13833 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13834 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13836 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
13838 /* Simple cases: Value already set, does match or doesn't. */
13839 if (targ != NULL_TREE && template_args_equal (targ, arg))
13846 /* If PARM is `const T' and ARG is only `int', we don't have
13847 a match unless we are allowing additional qualification.
13848 If ARG is `const int' and PARM is just `T' that's OK;
13849 that binds `const int' to `T'. */
13850 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
13854 /* Consider the case where ARG is `const volatile int' and
13855 PARM is `const T'. Then, T should be `volatile int'. */
13856 arg = cp_build_qualified_type_real
13857 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
13858 if (arg == error_mark_node)
13861 /* Simple cases: Value already set, does match or doesn't. */
13862 if (targ != NULL_TREE && same_type_p (targ, arg))
13867 /* Make sure that ARG is not a variable-sized array. (Note
13868 that were talking about variable-sized arrays (like
13869 `int[n]'), rather than arrays of unknown size (like
13870 `int[]').) We'll get very confused by such a type since
13871 the bound of the array will not be computable in an
13872 instantiation. Besides, such types are not allowed in
13873 ISO C++, so we can do as we please here. */
13874 if (variably_modified_type_p (arg, NULL_TREE))
13877 /* Strip typedefs as in convert_template_argument. */
13878 arg = strip_typedefs (arg);
13881 /* If ARG is a parameter pack or an expansion, we cannot unify
13882 against it unless PARM is also a parameter pack. */
13883 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
13884 && !template_parameter_pack_p (parm))
13887 /* If the argument deduction results is a METHOD_TYPE,
13888 then there is a problem.
13889 METHOD_TYPE doesn't map to any real C++ type the result of
13890 the deduction can not be of that type. */
13891 if (TREE_CODE (arg) == METHOD_TYPE)
13894 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
13897 case TEMPLATE_PARM_INDEX:
13898 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
13899 if (tparm == error_mark_node)
13902 if (TEMPLATE_PARM_LEVEL (parm)
13903 != template_decl_level (tparm))
13904 /* The PARM is not one we're trying to unify. Just check
13905 to see if it matches ARG. */
13906 return !(TREE_CODE (arg) == TREE_CODE (parm)
13907 && cp_tree_equal (parm, arg));
13909 idx = TEMPLATE_PARM_IDX (parm);
13910 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
13913 return !cp_tree_equal (targ, arg);
13915 /* [temp.deduct.type] If, in the declaration of a function template
13916 with a non-type template-parameter, the non-type
13917 template-parameter is used in an expression in the function
13918 parameter-list and, if the corresponding template-argument is
13919 deduced, the template-argument type shall match the type of the
13920 template-parameter exactly, except that a template-argument
13921 deduced from an array bound may be of any integral type.
13922 The non-type parameter might use already deduced type parameters. */
13923 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
13924 if (!TREE_TYPE (arg))
13925 /* Template-parameter dependent expression. Just accept it for now.
13926 It will later be processed in convert_template_argument. */
13928 else if (same_type_p (TREE_TYPE (arg), tparm))
13930 else if ((strict & UNIFY_ALLOW_INTEGER)
13931 && (TREE_CODE (tparm) == INTEGER_TYPE
13932 || TREE_CODE (tparm) == BOOLEAN_TYPE))
13933 /* Convert the ARG to the type of PARM; the deduced non-type
13934 template argument must exactly match the types of the
13935 corresponding parameter. */
13936 arg = fold (build_nop (tparm, arg));
13937 else if (uses_template_parms (tparm))
13938 /* We haven't deduced the type of this parameter yet. Try again
13944 /* If ARG is a parameter pack or an expansion, we cannot unify
13945 against it unless PARM is also a parameter pack. */
13946 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
13947 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
13950 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
13955 /* A pointer-to-member constant can be unified only with
13956 another constant. */
13957 if (TREE_CODE (arg) != PTRMEM_CST)
13960 /* Just unify the class member. It would be useless (and possibly
13961 wrong, depending on the strict flags) to unify also
13962 PTRMEM_CST_CLASS, because we want to be sure that both parm and
13963 arg refer to the same variable, even if through different
13964 classes. For instance:
13966 struct A { int x; };
13969 Unification of &A::x and &B::x must succeed. */
13970 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
13971 PTRMEM_CST_MEMBER (arg), strict);
13976 if (TREE_CODE (arg) != POINTER_TYPE)
13979 /* [temp.deduct.call]
13981 A can be another pointer or pointer to member type that can
13982 be converted to the deduced A via a qualification
13983 conversion (_conv.qual_).
13985 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
13986 This will allow for additional cv-qualification of the
13987 pointed-to types if appropriate. */
13989 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
13990 /* The derived-to-base conversion only persists through one
13991 level of pointers. */
13992 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
13994 return unify (tparms, targs, TREE_TYPE (parm),
13995 TREE_TYPE (arg), strict);
13998 case REFERENCE_TYPE:
13999 if (TREE_CODE (arg) != REFERENCE_TYPE)
14001 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14002 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14005 if (TREE_CODE (arg) != ARRAY_TYPE)
14007 if ((TYPE_DOMAIN (parm) == NULL_TREE)
14008 != (TYPE_DOMAIN (arg) == NULL_TREE))
14010 if (TYPE_DOMAIN (parm) != NULL_TREE)
14017 /* Our representation of array types uses "N - 1" as the
14018 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
14019 not an integer constant. We cannot unify arbitrarily
14020 complex expressions, so we eliminate the MINUS_EXPRs
14022 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
14023 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
14026 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
14027 parm_max = TREE_OPERAND (parm_max, 0);
14029 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
14030 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
14033 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
14034 trying to unify the type of a variable with the type
14035 of a template parameter. For example:
14037 template <unsigned int N>
14038 void f (char (&) [N]);
14045 Here, the type of the ARG will be "int [g(i)]", and
14046 may be a SAVE_EXPR, etc. */
14047 if (TREE_CODE (arg_max) != MINUS_EXPR)
14049 arg_max = TREE_OPERAND (arg_max, 0);
14052 /* If only one of the bounds used a MINUS_EXPR, compensate
14053 by adding one to the other bound. */
14054 if (parm_cst && !arg_cst)
14055 parm_max = fold_build2_loc (input_location, PLUS_EXPR,
14059 else if (arg_cst && !parm_cst)
14060 arg_max = fold_build2_loc (input_location, PLUS_EXPR,
14065 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
14068 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14069 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14076 case ENUMERAL_TYPE:
14078 if (TREE_CODE (arg) != TREE_CODE (parm))
14081 /* We have already checked cv-qualification at the top of the
14083 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
14086 /* As far as unification is concerned, this wins. Later checks
14087 will invalidate it if necessary. */
14090 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
14091 /* Type INTEGER_CST can come from ordinary constant template args. */
14093 while (TREE_CODE (arg) == NOP_EXPR)
14094 arg = TREE_OPERAND (arg, 0);
14096 if (TREE_CODE (arg) != INTEGER_CST)
14098 return !tree_int_cst_equal (parm, arg);
14103 if (TREE_CODE (arg) != TREE_VEC)
14105 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
14107 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
14108 if (unify (tparms, targs,
14109 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
14117 if (TREE_CODE (arg) != TREE_CODE (parm))
14120 if (TYPE_PTRMEMFUNC_P (parm))
14122 if (!TYPE_PTRMEMFUNC_P (arg))
14125 return unify (tparms, targs,
14126 TYPE_PTRMEMFUNC_FN_TYPE (parm),
14127 TYPE_PTRMEMFUNC_FN_TYPE (arg),
14131 if (CLASSTYPE_TEMPLATE_INFO (parm))
14133 tree t = NULL_TREE;
14135 if (strict_in & UNIFY_ALLOW_DERIVED)
14137 /* First, we try to unify the PARM and ARG directly. */
14138 t = try_class_unification (tparms, targs,
14143 /* Fallback to the special case allowed in
14144 [temp.deduct.call]:
14146 If P is a class, and P has the form
14147 template-id, then A can be a derived class of
14148 the deduced A. Likewise, if P is a pointer to
14149 a class of the form template-id, A can be a
14150 pointer to a derived class pointed to by the
14152 t = get_template_base (tparms, targs, parm, arg);
14158 else if (CLASSTYPE_TEMPLATE_INFO (arg)
14159 && (CLASSTYPE_TI_TEMPLATE (parm)
14160 == CLASSTYPE_TI_TEMPLATE (arg)))
14161 /* Perhaps PARM is something like S<U> and ARG is S<int>.
14162 Then, we should unify `int' and `U'. */
14165 /* There's no chance of unification succeeding. */
14168 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
14169 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
14171 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
14176 case FUNCTION_TYPE:
14178 unsigned int nargs;
14183 if (TREE_CODE (arg) != TREE_CODE (parm))
14186 /* CV qualifications for methods can never be deduced, they must
14187 match exactly. We need to check them explicitly here,
14188 because type_unification_real treats them as any other
14189 cv-qualified parameter. */
14190 if (TREE_CODE (parm) == METHOD_TYPE
14191 && (!check_cv_quals_for_unify
14193 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
14194 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
14197 if (unify (tparms, targs, TREE_TYPE (parm),
14198 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
14201 nargs = list_length (TYPE_ARG_TYPES (arg));
14202 args = XALLOCAVEC (tree, nargs);
14203 for (a = TYPE_ARG_TYPES (arg), i = 0;
14204 a != NULL_TREE && a != void_list_node;
14205 a = TREE_CHAIN (a), ++i)
14206 args[i] = TREE_VALUE (a);
14209 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
14210 args, nargs, 1, DEDUCE_EXACT,
14215 /* Unify a pointer to member with a pointer to member function, which
14216 deduces the type of the member as a function type. */
14217 if (TYPE_PTRMEMFUNC_P (arg))
14221 cp_cv_quals cv_quals;
14223 /* Check top-level cv qualifiers */
14224 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
14227 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14228 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
14231 /* Determine the type of the function we are unifying against. */
14232 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
14234 build_function_type (TREE_TYPE (method_type),
14235 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
14237 /* Extract the cv-qualifiers of the member function from the
14238 implicit object parameter and place them on the function
14239 type to be restored later. */
14241 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
14242 fntype = build_qualified_type (fntype, cv_quals);
14243 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
14246 if (TREE_CODE (arg) != OFFSET_TYPE)
14248 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14249 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
14251 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14255 if (DECL_TEMPLATE_PARM_P (parm))
14256 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
14257 if (arg != integral_constant_value (parm))
14262 case TEMPLATE_DECL:
14263 /* Matched cases are handled by the ARG == PARM test above. */
14266 case TYPE_ARGUMENT_PACK:
14267 case NONTYPE_ARGUMENT_PACK:
14269 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
14270 tree packed_args = ARGUMENT_PACK_ARGS (arg);
14271 int i, len = TREE_VEC_LENGTH (packed_parms);
14272 int argslen = TREE_VEC_LENGTH (packed_args);
14273 int parm_variadic_p = 0;
14275 for (i = 0; i < len; ++i)
14277 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
14280 /* We can unify against something with a trailing
14282 parm_variadic_p = 1;
14284 /* Since there is something following the pack
14285 expansion, we cannot unify this template argument
14292 /* If we don't have enough arguments to satisfy the parameters
14293 (not counting the pack expression at the end), or we have
14294 too many arguments for a parameter list that doesn't end in
14295 a pack expression, we can't unify. */
14296 if (argslen < (len - parm_variadic_p)
14297 || (argslen > len && !parm_variadic_p))
14300 /* Unify all of the parameters that precede the (optional)
14301 pack expression. */
14302 for (i = 0; i < len - parm_variadic_p; ++i)
14304 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
14305 TREE_VEC_ELT (packed_args, i), strict))
14309 if (parm_variadic_p)
14310 return unify_pack_expansion (tparms, targs,
14311 packed_parms, packed_args,
14312 strict, /*call_args_p=*/false,
14320 case DECLTYPE_TYPE:
14321 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
14326 /* Unification fails if we hit an error node. */
14330 gcc_assert (EXPR_P (parm));
14332 /* We must be looking at an expression. This can happen with
14336 void foo(S<I>, S<I + 2>);
14338 This is a "nondeduced context":
14342 The nondeduced contexts are:
14344 --A type that is a template-id in which one or more of
14345 the template-arguments is an expression that references
14346 a template-parameter.
14348 In these cases, we assume deduction succeeded, but don't
14349 actually infer any unifications. */
14351 if (!uses_template_parms (parm)
14352 && !template_args_equal (parm, arg))
14359 /* Note that DECL can be defined in this translation unit, if
14363 mark_definable (tree decl)
14366 DECL_NOT_REALLY_EXTERN (decl) = 1;
14367 FOR_EACH_CLONE (clone, decl)
14368 DECL_NOT_REALLY_EXTERN (clone) = 1;
14371 /* Called if RESULT is explicitly instantiated, or is a member of an
14372 explicitly instantiated class. */
14375 mark_decl_instantiated (tree result, int extern_p)
14377 SET_DECL_EXPLICIT_INSTANTIATION (result);
14379 /* If this entity has already been written out, it's too late to
14380 make any modifications. */
14381 if (TREE_ASM_WRITTEN (result))
14384 if (TREE_CODE (result) != FUNCTION_DECL)
14385 /* The TREE_PUBLIC flag for function declarations will have been
14386 set correctly by tsubst. */
14387 TREE_PUBLIC (result) = 1;
14389 /* This might have been set by an earlier implicit instantiation. */
14390 DECL_COMDAT (result) = 0;
14393 DECL_NOT_REALLY_EXTERN (result) = 0;
14396 mark_definable (result);
14397 /* Always make artificials weak. */
14398 if (DECL_ARTIFICIAL (result) && flag_weak)
14399 comdat_linkage (result);
14400 /* For WIN32 we also want to put explicit instantiations in
14401 linkonce sections. */
14402 else if (TREE_PUBLIC (result))
14403 maybe_make_one_only (result);
14406 /* If EXTERN_P, then this function will not be emitted -- unless
14407 followed by an explicit instantiation, at which point its linkage
14408 will be adjusted. If !EXTERN_P, then this function will be
14409 emitted here. In neither circumstance do we want
14410 import_export_decl to adjust the linkage. */
14411 DECL_INTERFACE_KNOWN (result) = 1;
14414 /* Given two function templates PAT1 and PAT2, return:
14416 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
14417 -1 if PAT2 is more specialized than PAT1.
14418 0 if neither is more specialized.
14420 LEN indicates the number of parameters we should consider
14421 (defaulted parameters should not be considered).
14423 The 1998 std underspecified function template partial ordering, and
14424 DR214 addresses the issue. We take pairs of arguments, one from
14425 each of the templates, and deduce them against each other. One of
14426 the templates will be more specialized if all the *other*
14427 template's arguments deduce against its arguments and at least one
14428 of its arguments *does* *not* deduce against the other template's
14429 corresponding argument. Deduction is done as for class templates.
14430 The arguments used in deduction have reference and top level cv
14431 qualifiers removed. Iff both arguments were originally reference
14432 types *and* deduction succeeds in both directions, the template
14433 with the more cv-qualified argument wins for that pairing (if
14434 neither is more cv-qualified, they both are equal). Unlike regular
14435 deduction, after all the arguments have been deduced in this way,
14436 we do *not* verify the deduced template argument values can be
14437 substituted into non-deduced contexts, nor do we have to verify
14438 that all template arguments have been deduced. */
14441 more_specialized_fn (tree pat1, tree pat2, int len)
14443 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
14444 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
14445 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
14446 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
14447 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
14448 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
14449 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
14450 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
14454 /* Remove the this parameter from non-static member functions. If
14455 one is a non-static member function and the other is not a static
14456 member function, remove the first parameter from that function
14457 also. This situation occurs for operator functions where we
14458 locate both a member function (with this pointer) and non-member
14459 operator (with explicit first operand). */
14460 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
14462 len--; /* LEN is the number of significant arguments for DECL1 */
14463 args1 = TREE_CHAIN (args1);
14464 if (!DECL_STATIC_FUNCTION_P (decl2))
14465 args2 = TREE_CHAIN (args2);
14467 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
14469 args2 = TREE_CHAIN (args2);
14470 if (!DECL_STATIC_FUNCTION_P (decl1))
14473 args1 = TREE_CHAIN (args1);
14477 /* If only one is a conversion operator, they are unordered. */
14478 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
14481 /* Consider the return type for a conversion function */
14482 if (DECL_CONV_FN_P (decl1))
14484 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
14485 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
14489 processing_template_decl++;
14492 /* Stop when an ellipsis is seen. */
14493 && args1 != NULL_TREE && args2 != NULL_TREE)
14495 tree arg1 = TREE_VALUE (args1);
14496 tree arg2 = TREE_VALUE (args2);
14497 int deduce1, deduce2;
14501 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
14502 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
14504 /* When both arguments are pack expansions, we need only
14505 unify the patterns themselves. */
14506 arg1 = PACK_EXPANSION_PATTERN (arg1);
14507 arg2 = PACK_EXPANSION_PATTERN (arg2);
14509 /* This is the last comparison we need to do. */
14513 if (TREE_CODE (arg1) == REFERENCE_TYPE)
14515 arg1 = TREE_TYPE (arg1);
14516 quals1 = cp_type_quals (arg1);
14519 if (TREE_CODE (arg2) == REFERENCE_TYPE)
14521 arg2 = TREE_TYPE (arg2);
14522 quals2 = cp_type_quals (arg2);
14525 if ((quals1 < 0) != (quals2 < 0))
14527 /* Only of the args is a reference, see if we should apply
14528 array/function pointer decay to it. This is not part of
14529 DR214, but is, IMHO, consistent with the deduction rules
14530 for the function call itself, and with our earlier
14531 implementation of the underspecified partial ordering
14532 rules. (nathan). */
14535 switch (TREE_CODE (arg1))
14538 arg1 = TREE_TYPE (arg1);
14540 case FUNCTION_TYPE:
14541 arg1 = build_pointer_type (arg1);
14550 switch (TREE_CODE (arg2))
14553 arg2 = TREE_TYPE (arg2);
14555 case FUNCTION_TYPE:
14556 arg2 = build_pointer_type (arg2);
14565 arg1 = TYPE_MAIN_VARIANT (arg1);
14566 arg2 = TYPE_MAIN_VARIANT (arg2);
14568 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
14570 int i, len2 = list_length (args2);
14571 tree parmvec = make_tree_vec (1);
14572 tree argvec = make_tree_vec (len2);
14575 /* Setup the parameter vector, which contains only ARG1. */
14576 TREE_VEC_ELT (parmvec, 0) = arg1;
14578 /* Setup the argument vector, which contains the remaining
14580 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
14581 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
14583 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
14584 argvec, UNIFY_ALLOW_NONE,
14585 /*call_args_p=*/false,
14588 /* We cannot deduce in the other direction, because ARG1 is
14589 a pack expansion but ARG2 is not. */
14592 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
14594 int i, len1 = list_length (args1);
14595 tree parmvec = make_tree_vec (1);
14596 tree argvec = make_tree_vec (len1);
14599 /* Setup the parameter vector, which contains only ARG1. */
14600 TREE_VEC_ELT (parmvec, 0) = arg2;
14602 /* Setup the argument vector, which contains the remaining
14604 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
14605 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
14607 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
14608 argvec, UNIFY_ALLOW_NONE,
14609 /*call_args_p=*/false,
14612 /* We cannot deduce in the other direction, because ARG2 is
14613 a pack expansion but ARG1 is not.*/
14619 /* The normal case, where neither argument is a pack
14621 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
14622 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
14629 if (better1 < 0 && better2 < 0)
14630 /* We've failed to deduce something in either direction.
14631 These must be unordered. */
14634 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
14636 /* Deduces in both directions, see if quals can
14637 disambiguate. Pretend the worse one failed to deduce. */
14638 if ((quals1 & quals2) == quals2)
14640 if ((quals1 & quals2) == quals1)
14643 if (deduce1 && !deduce2 && !better2)
14645 if (deduce2 && !deduce1 && !better1)
14648 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
14649 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
14650 /* We have already processed all of the arguments in our
14651 handing of the pack expansion type. */
14654 args1 = TREE_CHAIN (args1);
14655 args2 = TREE_CHAIN (args2);
14658 processing_template_decl--;
14660 /* All things being equal, if the next argument is a pack expansion
14661 for one function but not for the other, prefer the
14662 non-variadic function. */
14663 if ((better1 > 0) - (better2 > 0) == 0
14664 && args1 && TREE_VALUE (args1)
14665 && args2 && TREE_VALUE (args2))
14667 if (TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION)
14668 return TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION ? 0 : -1;
14669 else if (TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION)
14673 return (better1 > 0) - (better2 > 0);
14676 /* Determine which of two partial specializations is more specialized.
14678 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
14679 to the first partial specialization. The TREE_VALUE is the
14680 innermost set of template parameters for the partial
14681 specialization. PAT2 is similar, but for the second template.
14683 Return 1 if the first partial specialization is more specialized;
14684 -1 if the second is more specialized; 0 if neither is more
14687 See [temp.class.order] for information about determining which of
14688 two templates is more specialized. */
14691 more_specialized_class (tree pat1, tree pat2)
14696 bool any_deductions = false;
14698 tmpl1 = TREE_TYPE (pat1);
14699 tmpl2 = TREE_TYPE (pat2);
14701 /* Just like what happens for functions, if we are ordering between
14702 different class template specializations, we may encounter dependent
14703 types in the arguments, and we need our dependency check functions
14704 to behave correctly. */
14705 ++processing_template_decl;
14706 targs = get_class_bindings (TREE_VALUE (pat1),
14707 CLASSTYPE_TI_ARGS (tmpl1),
14708 CLASSTYPE_TI_ARGS (tmpl2));
14712 any_deductions = true;
14715 targs = get_class_bindings (TREE_VALUE (pat2),
14716 CLASSTYPE_TI_ARGS (tmpl2),
14717 CLASSTYPE_TI_ARGS (tmpl1));
14721 any_deductions = true;
14723 --processing_template_decl;
14725 /* In the case of a tie where at least one of the class templates
14726 has a parameter pack at the end, the template with the most
14727 non-packed parameters wins. */
14730 && (template_args_variadic_p (TREE_PURPOSE (pat1))
14731 || template_args_variadic_p (TREE_PURPOSE (pat2))))
14733 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
14734 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
14735 int len1 = TREE_VEC_LENGTH (args1);
14736 int len2 = TREE_VEC_LENGTH (args2);
14738 /* We don't count the pack expansion at the end. */
14739 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
14741 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
14746 else if (len1 < len2)
14753 /* Return the template arguments that will produce the function signature
14754 DECL from the function template FN, with the explicit template
14755 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
14756 also match. Return NULL_TREE if no satisfactory arguments could be
14760 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
14762 int ntparms = DECL_NTPARMS (fn);
14763 tree targs = make_tree_vec (ntparms);
14765 tree decl_arg_types;
14767 unsigned int nargs, ix;
14770 /* Substitute the explicit template arguments into the type of DECL.
14771 The call to fn_type_unification will handle substitution into the
14773 decl_type = TREE_TYPE (decl);
14774 if (explicit_args && uses_template_parms (decl_type))
14777 tree converted_args;
14779 if (DECL_TEMPLATE_INFO (decl))
14780 tmpl = DECL_TI_TEMPLATE (decl);
14782 /* We can get here for some invalid specializations. */
14786 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
14787 explicit_args, NULL_TREE,
14789 /*require_all_args=*/false,
14790 /*use_default_args=*/false);
14791 if (converted_args == error_mark_node)
14794 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
14795 if (decl_type == error_mark_node)
14799 /* Never do unification on the 'this' parameter. */
14800 decl_arg_types = skip_artificial_parms_for (decl,
14801 TYPE_ARG_TYPES (decl_type));
14803 nargs = list_length (decl_arg_types);
14804 args = XALLOCAVEC (tree, nargs);
14805 for (arg = decl_arg_types, ix = 0;
14806 arg != NULL_TREE && arg != void_list_node;
14807 arg = TREE_CHAIN (arg), ++ix)
14808 args[ix] = TREE_VALUE (arg);
14810 if (fn_type_unification (fn, explicit_args, targs,
14812 (check_rettype || DECL_CONV_FN_P (fn)
14813 ? TREE_TYPE (decl_type) : NULL_TREE),
14814 DEDUCE_EXACT, LOOKUP_NORMAL))
14820 /* Return the innermost template arguments that, when applied to a
14821 template specialization whose innermost template parameters are
14822 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
14825 For example, suppose we have:
14827 template <class T, class U> struct S {};
14828 template <class T> struct S<T*, int> {};
14830 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
14831 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
14832 int}. The resulting vector will be {double}, indicating that `T'
14833 is bound to `double'. */
14836 get_class_bindings (tree tparms, tree spec_args, tree args)
14838 int i, ntparms = TREE_VEC_LENGTH (tparms);
14840 tree innermost_deduced_args;
14842 innermost_deduced_args = make_tree_vec (ntparms);
14843 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
14845 deduced_args = copy_node (args);
14846 SET_TMPL_ARGS_LEVEL (deduced_args,
14847 TMPL_ARGS_DEPTH (deduced_args),
14848 innermost_deduced_args);
14851 deduced_args = innermost_deduced_args;
14853 if (unify (tparms, deduced_args,
14854 INNERMOST_TEMPLATE_ARGS (spec_args),
14855 INNERMOST_TEMPLATE_ARGS (args),
14859 for (i = 0; i < ntparms; ++i)
14860 if (! TREE_VEC_ELT (innermost_deduced_args, i))
14863 /* Verify that nondeduced template arguments agree with the type
14864 obtained from argument deduction.
14868 struct A { typedef int X; };
14869 template <class T, class U> struct C {};
14870 template <class T> struct C<T, typename T::X> {};
14872 Then with the instantiation `C<A, int>', we can deduce that
14873 `T' is `A' but unify () does not check whether `typename T::X'
14875 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
14876 if (spec_args == error_mark_node
14877 /* We only need to check the innermost arguments; the other
14878 arguments will always agree. */
14879 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
14880 INNERMOST_TEMPLATE_ARGS (args)))
14883 /* Now that we have bindings for all of the template arguments,
14884 ensure that the arguments deduced for the template template
14885 parameters have compatible template parameter lists. See the use
14886 of template_template_parm_bindings_ok_p in fn_type_unification
14887 for more information. */
14888 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
14891 return deduced_args;
14894 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
14895 Return the TREE_LIST node with the most specialized template, if
14896 any. If there is no most specialized template, the error_mark_node
14899 Note that this function does not look at, or modify, the
14900 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
14901 returned is one of the elements of INSTANTIATIONS, callers may
14902 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
14903 and retrieve it from the value returned. */
14906 most_specialized_instantiation (tree templates)
14910 ++processing_template_decl;
14913 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
14917 if (get_bindings (TREE_VALUE (champ),
14918 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
14919 NULL_TREE, /*check_ret=*/false))
14922 if (get_bindings (TREE_VALUE (fn),
14923 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
14924 NULL_TREE, /*check_ret=*/false))
14931 /* Equally specialized, move to next function. If there
14932 is no next function, nothing's most specialized. */
14933 fn = TREE_CHAIN (fn);
14941 /* Now verify that champ is better than everything earlier in the
14942 instantiation list. */
14943 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
14944 if (get_bindings (TREE_VALUE (champ),
14945 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
14946 NULL_TREE, /*check_ret=*/false)
14947 || !get_bindings (TREE_VALUE (fn),
14948 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
14949 NULL_TREE, /*check_ret=*/false))
14955 processing_template_decl--;
14958 return error_mark_node;
14963 /* If DECL is a specialization of some template, return the most
14964 general such template. Otherwise, returns NULL_TREE.
14966 For example, given:
14968 template <class T> struct S { template <class U> void f(U); };
14970 if TMPL is `template <class U> void S<int>::f(U)' this will return
14971 the full template. This function will not trace past partial
14972 specializations, however. For example, given in addition:
14974 template <class T> struct S<T*> { template <class U> void f(U); };
14976 if TMPL is `template <class U> void S<int*>::f(U)' this will return
14977 `template <class T> template <class U> S<T*>::f(U)'. */
14980 most_general_template (tree decl)
14982 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
14983 an immediate specialization. */
14984 if (TREE_CODE (decl) == FUNCTION_DECL)
14986 if (DECL_TEMPLATE_INFO (decl)) {
14987 decl = DECL_TI_TEMPLATE (decl);
14989 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
14990 template friend. */
14991 if (TREE_CODE (decl) != TEMPLATE_DECL)
14997 /* Look for more and more general templates. */
14998 while (DECL_TEMPLATE_INFO (decl))
15000 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
15001 (See cp-tree.h for details.) */
15002 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
15005 if (CLASS_TYPE_P (TREE_TYPE (decl))
15006 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
15009 /* Stop if we run into an explicitly specialized class template. */
15010 if (!DECL_NAMESPACE_SCOPE_P (decl)
15011 && DECL_CONTEXT (decl)
15012 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
15015 decl = DECL_TI_TEMPLATE (decl);
15021 /* Return the most specialized of the class template partial
15022 specializations of TMPL which can produce TYPE, a specialization of
15023 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
15024 a _TYPE node corresponding to the partial specialization, while the
15025 TREE_PURPOSE is the set of template arguments that must be
15026 substituted into the TREE_TYPE in order to generate TYPE.
15028 If the choice of partial specialization is ambiguous, a diagnostic
15029 is issued, and the error_mark_node is returned. If there are no
15030 partial specializations of TMPL matching TYPE, then NULL_TREE is
15034 most_specialized_class (tree type, tree tmpl)
15036 tree list = NULL_TREE;
15042 tree outer_args = NULL_TREE;
15044 tmpl = most_general_template (tmpl);
15045 args = CLASSTYPE_TI_ARGS (type);
15047 /* For determining which partial specialization to use, only the
15048 innermost args are interesting. */
15049 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15051 outer_args = strip_innermost_template_args (args, 1);
15052 args = INNERMOST_TEMPLATE_ARGS (args);
15055 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
15057 tree partial_spec_args;
15059 tree parms = TREE_VALUE (t);
15061 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
15066 ++processing_template_decl;
15068 /* Discard the outer levels of args, and then substitute in the
15069 template args from the enclosing class. */
15070 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
15071 partial_spec_args = tsubst_template_args
15072 (partial_spec_args, outer_args, tf_none, NULL_TREE);
15074 /* PARMS already refers to just the innermost parms, but the
15075 template parms in partial_spec_args had their levels lowered
15076 by tsubst, so we need to do the same for the parm list. We
15077 can't just tsubst the TREE_VEC itself, as tsubst wants to
15078 treat a TREE_VEC as an argument vector. */
15079 parms = copy_node (parms);
15080 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
15081 TREE_VEC_ELT (parms, i) =
15082 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
15084 --processing_template_decl;
15086 spec_args = get_class_bindings (parms,
15092 spec_args = add_to_template_args (outer_args, spec_args);
15093 list = tree_cons (spec_args, TREE_VALUE (t), list);
15094 TREE_TYPE (list) = TREE_TYPE (t);
15101 ambiguous_p = false;
15104 t = TREE_CHAIN (t);
15105 for (; t; t = TREE_CHAIN (t))
15107 fate = more_specialized_class (champ, t);
15114 t = TREE_CHAIN (t);
15117 ambiguous_p = true;
15126 for (t = list; t && t != champ; t = TREE_CHAIN (t))
15128 fate = more_specialized_class (champ, t);
15131 ambiguous_p = true;
15138 const char *str = "candidates are:";
15139 error ("ambiguous class template instantiation for %q#T", type);
15140 for (t = list; t; t = TREE_CHAIN (t))
15142 error ("%s %+#T", str, TREE_TYPE (t));
15145 return error_mark_node;
15151 /* Explicitly instantiate DECL. */
15154 do_decl_instantiation (tree decl, tree storage)
15156 tree result = NULL_TREE;
15159 if (!decl || decl == error_mark_node)
15160 /* An error occurred, for which grokdeclarator has already issued
15161 an appropriate message. */
15163 else if (! DECL_LANG_SPECIFIC (decl))
15165 error ("explicit instantiation of non-template %q#D", decl);
15168 else if (TREE_CODE (decl) == VAR_DECL)
15170 /* There is an asymmetry here in the way VAR_DECLs and
15171 FUNCTION_DECLs are handled by grokdeclarator. In the case of
15172 the latter, the DECL we get back will be marked as a
15173 template instantiation, and the appropriate
15174 DECL_TEMPLATE_INFO will be set up. This does not happen for
15175 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
15176 should handle VAR_DECLs as it currently handles
15178 if (!DECL_CLASS_SCOPE_P (decl))
15180 error ("%qD is not a static data member of a class template", decl);
15183 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
15184 if (!result || TREE_CODE (result) != VAR_DECL)
15186 error ("no matching template for %qD found", decl);
15189 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
15191 error ("type %qT for explicit instantiation %qD does not match "
15192 "declared type %qT", TREE_TYPE (result), decl,
15197 else if (TREE_CODE (decl) != FUNCTION_DECL)
15199 error ("explicit instantiation of %q#D", decl);
15205 /* Check for various error cases. Note that if the explicit
15206 instantiation is valid the RESULT will currently be marked as an
15207 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
15208 until we get here. */
15210 if (DECL_TEMPLATE_SPECIALIZATION (result))
15212 /* DR 259 [temp.spec].
15214 Both an explicit instantiation and a declaration of an explicit
15215 specialization shall not appear in a program unless the explicit
15216 instantiation follows a declaration of the explicit specialization.
15218 For a given set of template parameters, if an explicit
15219 instantiation of a template appears after a declaration of an
15220 explicit specialization for that template, the explicit
15221 instantiation has no effect. */
15224 else if (DECL_EXPLICIT_INSTANTIATION (result))
15228 No program shall explicitly instantiate any template more
15231 We check DECL_NOT_REALLY_EXTERN so as not to complain when
15232 the first instantiation was `extern' and the second is not,
15233 and EXTERN_P for the opposite case. */
15234 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
15235 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
15236 /* If an "extern" explicit instantiation follows an ordinary
15237 explicit instantiation, the template is instantiated. */
15241 else if (!DECL_IMPLICIT_INSTANTIATION (result))
15243 error ("no matching template for %qD found", result);
15246 else if (!DECL_TEMPLATE_INFO (result))
15248 permerror (input_location, "explicit instantiation of non-template %q#D", result);
15252 if (storage == NULL_TREE)
15254 else if (storage == ridpointers[(int) RID_EXTERN])
15256 if (!in_system_header && (cxx_dialect == cxx98))
15257 pedwarn (input_location, OPT_pedantic,
15258 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
15263 error ("storage class %qD applied to template instantiation", storage);
15265 check_explicit_instantiation_namespace (result);
15266 mark_decl_instantiated (result, extern_p);
15268 instantiate_decl (result, /*defer_ok=*/1,
15269 /*expl_inst_class_mem_p=*/false);
15273 mark_class_instantiated (tree t, int extern_p)
15275 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
15276 SET_CLASSTYPE_INTERFACE_KNOWN (t);
15277 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
15278 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
15281 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
15282 rest_of_type_compilation (t, 1);
15286 /* Called from do_type_instantiation through binding_table_foreach to
15287 do recursive instantiation for the type bound in ENTRY. */
15289 bt_instantiate_type_proc (binding_entry entry, void *data)
15291 tree storage = *(tree *) data;
15293 if (MAYBE_CLASS_TYPE_P (entry->type)
15294 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
15295 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
15298 /* Called from do_type_instantiation to instantiate a member
15299 (a member function or a static member variable) of an
15300 explicitly instantiated class template. */
15302 instantiate_class_member (tree decl, int extern_p)
15304 mark_decl_instantiated (decl, extern_p);
15306 instantiate_decl (decl, /*defer_ok=*/1,
15307 /*expl_inst_class_mem_p=*/true);
15310 /* Perform an explicit instantiation of template class T. STORAGE, if
15311 non-null, is the RID for extern, inline or static. COMPLAIN is
15312 nonzero if this is called from the parser, zero if called recursively,
15313 since the standard is unclear (as detailed below). */
15316 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
15321 int previous_instantiation_extern_p = 0;
15323 if (TREE_CODE (t) == TYPE_DECL)
15326 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
15328 error ("explicit instantiation of non-template type %qT", t);
15334 if (!COMPLETE_TYPE_P (t))
15336 if (complain & tf_error)
15337 error ("explicit instantiation of %q#T before definition of template",
15342 if (storage != NULL_TREE)
15344 if (!in_system_header)
15346 if (storage == ridpointers[(int) RID_EXTERN])
15348 if (cxx_dialect == cxx98)
15349 pedwarn (input_location, OPT_pedantic,
15350 "ISO C++ 1998 forbids the use of %<extern%> on "
15351 "explicit instantiations");
15354 pedwarn (input_location, OPT_pedantic,
15355 "ISO C++ forbids the use of %qE"
15356 " on explicit instantiations", storage);
15359 if (storage == ridpointers[(int) RID_INLINE])
15361 else if (storage == ridpointers[(int) RID_EXTERN])
15363 else if (storage == ridpointers[(int) RID_STATIC])
15367 error ("storage class %qD applied to template instantiation",
15373 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
15375 /* DR 259 [temp.spec].
15377 Both an explicit instantiation and a declaration of an explicit
15378 specialization shall not appear in a program unless the explicit
15379 instantiation follows a declaration of the explicit specialization.
15381 For a given set of template parameters, if an explicit
15382 instantiation of a template appears after a declaration of an
15383 explicit specialization for that template, the explicit
15384 instantiation has no effect. */
15387 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
15391 No program shall explicitly instantiate any template more
15394 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
15395 instantiation was `extern'. If EXTERN_P then the second is.
15396 These cases are OK. */
15397 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
15399 if (!previous_instantiation_extern_p && !extern_p
15400 && (complain & tf_error))
15401 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
15403 /* If we've already instantiated the template, just return now. */
15404 if (!CLASSTYPE_INTERFACE_ONLY (t))
15408 check_explicit_instantiation_namespace (TYPE_NAME (t));
15409 mark_class_instantiated (t, extern_p);
15417 /* In contrast to implicit instantiation, where only the
15418 declarations, and not the definitions, of members are
15419 instantiated, we have here:
15423 The explicit instantiation of a class template specialization
15424 implies the instantiation of all of its members not
15425 previously explicitly specialized in the translation unit
15426 containing the explicit instantiation.
15428 Of course, we can't instantiate member template classes, since
15429 we don't have any arguments for them. Note that the standard
15430 is unclear on whether the instantiation of the members are
15431 *explicit* instantiations or not. However, the most natural
15432 interpretation is that it should be an explicit instantiation. */
15435 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
15436 if (TREE_CODE (tmp) == FUNCTION_DECL
15437 && DECL_TEMPLATE_INSTANTIATION (tmp))
15438 instantiate_class_member (tmp, extern_p);
15440 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
15441 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
15442 instantiate_class_member (tmp, extern_p);
15444 if (CLASSTYPE_NESTED_UTDS (t))
15445 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
15446 bt_instantiate_type_proc, &storage);
15450 /* Given a function DECL, which is a specialization of TMPL, modify
15451 DECL to be a re-instantiation of TMPL with the same template
15452 arguments. TMPL should be the template into which tsubst'ing
15453 should occur for DECL, not the most general template.
15455 One reason for doing this is a scenario like this:
15458 void f(const T&, int i);
15460 void g() { f(3, 7); }
15463 void f(const T& t, const int i) { }
15465 Note that when the template is first instantiated, with
15466 instantiate_template, the resulting DECL will have no name for the
15467 first parameter, and the wrong type for the second. So, when we go
15468 to instantiate the DECL, we regenerate it. */
15471 regenerate_decl_from_template (tree decl, tree tmpl)
15473 /* The arguments used to instantiate DECL, from the most general
15478 args = DECL_TI_ARGS (decl);
15479 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
15481 /* Make sure that we can see identifiers, and compute access
15483 push_access_scope (decl);
15485 if (TREE_CODE (decl) == FUNCTION_DECL)
15493 args_depth = TMPL_ARGS_DEPTH (args);
15494 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
15495 if (args_depth > parms_depth)
15496 args = get_innermost_template_args (args, parms_depth);
15498 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
15499 args, tf_error, NULL_TREE);
15501 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
15504 /* Merge parameter declarations. */
15505 decl_parm = skip_artificial_parms_for (decl,
15506 DECL_ARGUMENTS (decl));
15508 = skip_artificial_parms_for (code_pattern,
15509 DECL_ARGUMENTS (code_pattern));
15510 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
15515 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
15516 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
15517 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
15519 parm_type = type_decays_to (parm_type);
15520 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
15521 TREE_TYPE (decl_parm) = parm_type;
15522 attributes = DECL_ATTRIBUTES (pattern_parm);
15523 if (DECL_ATTRIBUTES (decl_parm) != attributes)
15525 DECL_ATTRIBUTES (decl_parm) = attributes;
15526 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
15528 decl_parm = TREE_CHAIN (decl_parm);
15529 pattern_parm = TREE_CHAIN (pattern_parm);
15531 /* Merge any parameters that match with the function parameter
15533 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
15536 tree expanded_types;
15537 /* Expand the TYPE_PACK_EXPANSION that provides the types for
15538 the parameters in this function parameter pack. */
15539 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
15540 args, tf_error, NULL_TREE);
15541 len = TREE_VEC_LENGTH (expanded_types);
15542 for (i = 0; i < len; i++)
15547 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
15548 /* Rename the parameter to include the index. */
15549 DECL_NAME (decl_parm) =
15550 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
15551 parm_type = TREE_VEC_ELT (expanded_types, i);
15552 parm_type = type_decays_to (parm_type);
15553 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
15554 TREE_TYPE (decl_parm) = parm_type;
15555 attributes = DECL_ATTRIBUTES (pattern_parm);
15556 if (DECL_ATTRIBUTES (decl_parm) != attributes)
15558 DECL_ATTRIBUTES (decl_parm) = attributes;
15559 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
15561 decl_parm = TREE_CHAIN (decl_parm);
15564 /* Merge additional specifiers from the CODE_PATTERN. */
15565 if (DECL_DECLARED_INLINE_P (code_pattern)
15566 && !DECL_DECLARED_INLINE_P (decl))
15567 DECL_DECLARED_INLINE_P (decl) = 1;
15569 else if (TREE_CODE (decl) == VAR_DECL)
15570 DECL_INITIAL (decl) =
15571 tsubst_expr (DECL_INITIAL (code_pattern), args,
15572 tf_error, DECL_TI_TEMPLATE (decl),
15573 /*integral_constant_expression_p=*/false);
15575 gcc_unreachable ();
15577 pop_access_scope (decl);
15580 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
15581 substituted to get DECL. */
15584 template_for_substitution (tree decl)
15586 tree tmpl = DECL_TI_TEMPLATE (decl);
15588 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
15589 for the instantiation. This is not always the most general
15590 template. Consider, for example:
15593 struct S { template <class U> void f();
15594 template <> void f<int>(); };
15596 and an instantiation of S<double>::f<int>. We want TD to be the
15597 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
15598 while (/* An instantiation cannot have a definition, so we need a
15599 more general template. */
15600 DECL_TEMPLATE_INSTANTIATION (tmpl)
15601 /* We must also deal with friend templates. Given:
15603 template <class T> struct S {
15604 template <class U> friend void f() {};
15607 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
15608 so far as the language is concerned, but that's still
15609 where we get the pattern for the instantiation from. On
15610 other hand, if the definition comes outside the class, say:
15612 template <class T> struct S {
15613 template <class U> friend void f();
15615 template <class U> friend void f() {}
15617 we don't need to look any further. That's what the check for
15618 DECL_INITIAL is for. */
15619 || (TREE_CODE (decl) == FUNCTION_DECL
15620 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
15621 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
15623 /* The present template, TD, should not be a definition. If it
15624 were a definition, we should be using it! Note that we
15625 cannot restructure the loop to just keep going until we find
15626 a template with a definition, since that might go too far if
15627 a specialization was declared, but not defined. */
15628 gcc_assert (TREE_CODE (decl) != VAR_DECL
15629 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
15631 /* Fetch the more general template. */
15632 tmpl = DECL_TI_TEMPLATE (tmpl);
15638 /* Returns true if we need to instantiate this template instance even if we
15639 know we aren't going to emit it.. */
15642 always_instantiate_p (tree decl)
15644 /* We always instantiate inline functions so that we can inline them. An
15645 explicit instantiation declaration prohibits implicit instantiation of
15646 non-inline functions. With high levels of optimization, we would
15647 normally inline non-inline functions -- but we're not allowed to do
15648 that for "extern template" functions. Therefore, we check
15649 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */
15650 return ((TREE_CODE (decl) == FUNCTION_DECL
15651 && DECL_DECLARED_INLINE_P (decl))
15652 /* And we need to instantiate static data members so that
15653 their initializers are available in integral constant
15655 || (TREE_CODE (decl) == VAR_DECL
15656 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)));
15659 /* Produce the definition of D, a _DECL generated from a template. If
15660 DEFER_OK is nonzero, then we don't have to actually do the
15661 instantiation now; we just have to do it sometime. Normally it is
15662 an error if this is an explicit instantiation but D is undefined.
15663 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
15664 explicitly instantiated class template. */
15667 instantiate_decl (tree d, int defer_ok,
15668 bool expl_inst_class_mem_p)
15670 tree tmpl = DECL_TI_TEMPLATE (d);
15677 bool pattern_defined;
15679 location_t saved_loc = input_location;
15682 /* This function should only be used to instantiate templates for
15683 functions and static member variables. */
15684 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
15685 || TREE_CODE (d) == VAR_DECL);
15687 /* Variables are never deferred; if instantiation is required, they
15688 are instantiated right away. That allows for better code in the
15689 case that an expression refers to the value of the variable --
15690 if the variable has a constant value the referring expression can
15691 take advantage of that fact. */
15692 if (TREE_CODE (d) == VAR_DECL)
15695 /* Don't instantiate cloned functions. Instead, instantiate the
15696 functions they cloned. */
15697 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
15698 d = DECL_CLONED_FUNCTION (d);
15700 if (DECL_TEMPLATE_INSTANTIATED (d)
15701 || DECL_TEMPLATE_SPECIALIZATION (d))
15702 /* D has already been instantiated or explicitly specialized, so
15703 there's nothing for us to do here.
15705 It might seem reasonable to check whether or not D is an explicit
15706 instantiation, and, if so, stop here. But when an explicit
15707 instantiation is deferred until the end of the compilation,
15708 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
15709 the instantiation. */
15712 /* Check to see whether we know that this template will be
15713 instantiated in some other file, as with "extern template"
15715 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
15717 /* In general, we do not instantiate such templates. */
15718 if (external_p && !always_instantiate_p (d))
15721 gen_tmpl = most_general_template (tmpl);
15722 gen_args = DECL_TI_ARGS (d);
15724 if (tmpl != gen_tmpl)
15725 /* We should already have the extra args. */
15726 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
15727 == TMPL_ARGS_DEPTH (gen_args));
15728 /* And what's in the hash table should match D. */
15729 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
15730 || spec == NULL_TREE);
15732 /* This needs to happen before any tsubsting. */
15733 if (! push_tinst_level (d))
15736 timevar_push (TV_PARSE);
15738 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
15739 for the instantiation. */
15740 td = template_for_substitution (d);
15741 code_pattern = DECL_TEMPLATE_RESULT (td);
15743 /* We should never be trying to instantiate a member of a class
15744 template or partial specialization. */
15745 gcc_assert (d != code_pattern);
15747 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
15748 || DECL_TEMPLATE_SPECIALIZATION (td))
15749 /* In the case of a friend template whose definition is provided
15750 outside the class, we may have too many arguments. Drop the
15751 ones we don't need. The same is true for specializations. */
15752 args = get_innermost_template_args
15753 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
15757 if (TREE_CODE (d) == FUNCTION_DECL)
15758 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
15760 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
15762 /* We may be in the middle of deferred access check. Disable it now. */
15763 push_deferring_access_checks (dk_no_deferred);
15765 /* Unless an explicit instantiation directive has already determined
15766 the linkage of D, remember that a definition is available for
15768 if (pattern_defined
15769 && !DECL_INTERFACE_KNOWN (d)
15770 && !DECL_NOT_REALLY_EXTERN (d))
15771 mark_definable (d);
15773 input_location = DECL_SOURCE_LOCATION (d);
15775 /* If D is a member of an explicitly instantiated class template,
15776 and no definition is available, treat it like an implicit
15778 if (!pattern_defined && expl_inst_class_mem_p
15779 && DECL_EXPLICIT_INSTANTIATION (d))
15781 DECL_NOT_REALLY_EXTERN (d) = 0;
15782 DECL_INTERFACE_KNOWN (d) = 0;
15783 SET_DECL_IMPLICIT_INSTANTIATION (d);
15788 /* Recheck the substitutions to obtain any warning messages
15789 about ignoring cv qualifiers. */
15790 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
15791 tree type = TREE_TYPE (gen);
15793 /* Make sure that we can see identifiers, and compute access
15794 correctly. D is already the target FUNCTION_DECL with the
15796 push_access_scope (d);
15798 if (TREE_CODE (gen) == FUNCTION_DECL)
15800 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
15801 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
15803 /* Don't simply tsubst the function type, as that will give
15804 duplicate warnings about poor parameter qualifications.
15805 The function arguments are the same as the decl_arguments
15806 without the top level cv qualifiers. */
15807 type = TREE_TYPE (type);
15809 tsubst (type, gen_args, tf_warning_or_error, d);
15811 pop_access_scope (d);
15814 /* Defer all other templates, unless we have been explicitly
15815 forbidden from doing so. */
15816 if (/* If there is no definition, we cannot instantiate the
15819 /* If it's OK to postpone instantiation, do so. */
15821 /* If this is a static data member that will be defined
15822 elsewhere, we don't want to instantiate the entire data
15823 member, but we do want to instantiate the initializer so that
15824 we can substitute that elsewhere. */
15825 || (external_p && TREE_CODE (d) == VAR_DECL))
15827 /* The definition of the static data member is now required so
15828 we must substitute the initializer. */
15829 if (TREE_CODE (d) == VAR_DECL
15830 && !DECL_INITIAL (d)
15831 && DECL_INITIAL (code_pattern))
15836 ns = decl_namespace_context (d);
15837 push_nested_namespace (ns);
15838 push_nested_class (DECL_CONTEXT (d));
15839 init = tsubst_expr (DECL_INITIAL (code_pattern),
15841 tf_warning_or_error, NULL_TREE,
15842 /*integral_constant_expression_p=*/false);
15843 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
15844 /*asmspec_tree=*/NULL_TREE,
15845 LOOKUP_ONLYCONVERTING);
15846 pop_nested_class ();
15847 pop_nested_namespace (ns);
15850 /* We restore the source position here because it's used by
15851 add_pending_template. */
15852 input_location = saved_loc;
15854 if (at_eof && !pattern_defined
15855 && DECL_EXPLICIT_INSTANTIATION (d)
15856 && DECL_NOT_REALLY_EXTERN (d))
15859 The definition of a non-exported function template, a
15860 non-exported member function template, or a non-exported
15861 member function or static data member of a class template
15862 shall be present in every translation unit in which it is
15863 explicitly instantiated. */
15864 permerror (input_location, "explicit instantiation of %qD "
15865 "but no definition available", d);
15867 /* ??? Historically, we have instantiated inline functions, even
15868 when marked as "extern template". */
15869 if (!(external_p && TREE_CODE (d) == VAR_DECL))
15870 add_pending_template (d);
15873 /* Tell the repository that D is available in this translation unit
15874 -- and see if it is supposed to be instantiated here. */
15875 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
15877 /* In a PCH file, despite the fact that the repository hasn't
15878 requested instantiation in the PCH it is still possible that
15879 an instantiation will be required in a file that includes the
15882 add_pending_template (d);
15883 /* Instantiate inline functions so that the inliner can do its
15884 job, even though we'll not be emitting a copy of this
15886 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
15890 need_push = !cfun || !global_bindings_p ();
15892 push_to_top_level ();
15894 /* Mark D as instantiated so that recursive calls to
15895 instantiate_decl do not try to instantiate it again. */
15896 DECL_TEMPLATE_INSTANTIATED (d) = 1;
15898 /* Regenerate the declaration in case the template has been modified
15899 by a subsequent redeclaration. */
15900 regenerate_decl_from_template (d, td);
15902 /* We already set the file and line above. Reset them now in case
15903 they changed as a result of calling regenerate_decl_from_template. */
15904 input_location = DECL_SOURCE_LOCATION (d);
15906 if (TREE_CODE (d) == VAR_DECL)
15910 /* Clear out DECL_RTL; whatever was there before may not be right
15911 since we've reset the type of the declaration. */
15912 SET_DECL_RTL (d, NULL_RTX);
15913 DECL_IN_AGGR_P (d) = 0;
15915 /* The initializer is placed in DECL_INITIAL by
15916 regenerate_decl_from_template. Pull it out so that
15917 cp_finish_decl can process it. */
15918 init = DECL_INITIAL (d);
15919 DECL_INITIAL (d) = NULL_TREE;
15920 DECL_INITIALIZED_P (d) = 0;
15922 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
15923 initializer. That function will defer actual emission until
15924 we have a chance to determine linkage. */
15925 DECL_EXTERNAL (d) = 0;
15927 /* Enter the scope of D so that access-checking works correctly. */
15928 push_nested_class (DECL_CONTEXT (d));
15929 cp_finish_decl (d, init, false, NULL_TREE, 0);
15930 pop_nested_class ();
15932 else if (TREE_CODE (d) == FUNCTION_DECL)
15934 htab_t saved_local_specializations;
15939 /* Save away the current list, in case we are instantiating one
15940 template from within the body of another. */
15941 saved_local_specializations = local_specializations;
15943 /* Set up the list of local specializations. */
15944 local_specializations = htab_create (37,
15945 hash_local_specialization,
15946 eq_local_specializations,
15949 /* Set up context. */
15950 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
15952 /* Create substitution entries for the parameters. */
15953 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
15954 tmpl_parm = DECL_ARGUMENTS (subst_decl);
15955 spec_parm = DECL_ARGUMENTS (d);
15956 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
15958 register_local_specialization (spec_parm, tmpl_parm);
15959 spec_parm = skip_artificial_parms_for (d, spec_parm);
15960 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
15962 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
15964 register_local_specialization (spec_parm, tmpl_parm);
15965 tmpl_parm = TREE_CHAIN (tmpl_parm);
15966 spec_parm = TREE_CHAIN (spec_parm);
15968 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
15970 /* Register the (value) argument pack as a specialization of
15971 TMPL_PARM, then move on. */
15972 tree argpack = make_fnparm_pack (spec_parm);
15973 register_local_specialization (argpack, tmpl_parm);
15974 tmpl_parm = TREE_CHAIN (tmpl_parm);
15975 spec_parm = NULL_TREE;
15977 gcc_assert (!spec_parm);
15979 /* Substitute into the body of the function. */
15980 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
15981 tf_warning_or_error, tmpl,
15982 /*integral_constant_expression_p=*/false);
15984 /* Set the current input_location to the end of the function
15985 so that finish_function knows where we are. */
15986 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
15988 /* We don't need the local specializations any more. */
15989 htab_delete (local_specializations);
15990 local_specializations = saved_local_specializations;
15992 /* Finish the function. */
15993 d = finish_function (0);
15994 expand_or_defer_fn (d);
15997 /* We're not deferring instantiation any more. */
15998 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
16001 pop_from_top_level ();
16004 input_location = saved_loc;
16005 pop_deferring_access_checks ();
16006 pop_tinst_level ();
16008 timevar_pop (TV_PARSE);
16013 /* Run through the list of templates that we wish we could
16014 instantiate, and instantiate any we can. RETRIES is the
16015 number of times we retry pending template instantiation. */
16018 instantiate_pending_templates (int retries)
16021 location_t saved_loc = input_location;
16023 /* Instantiating templates may trigger vtable generation. This in turn
16024 may require further template instantiations. We place a limit here
16025 to avoid infinite loop. */
16026 if (pending_templates && retries >= max_tinst_depth)
16028 tree decl = pending_templates->tinst->decl;
16030 error ("template instantiation depth exceeds maximum of %d"
16031 " instantiating %q+D, possibly from virtual table generation"
16032 " (use -ftemplate-depth-NN to increase the maximum)",
16033 max_tinst_depth, decl);
16034 if (TREE_CODE (decl) == FUNCTION_DECL)
16035 /* Pretend that we defined it. */
16036 DECL_INITIAL (decl) = error_mark_node;
16042 struct pending_template **t = &pending_templates;
16043 struct pending_template *last = NULL;
16047 tree instantiation = reopen_tinst_level ((*t)->tinst);
16048 bool complete = false;
16050 if (TYPE_P (instantiation))
16054 if (!COMPLETE_TYPE_P (instantiation))
16056 instantiate_class_template (instantiation);
16057 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
16058 for (fn = TYPE_METHODS (instantiation);
16060 fn = TREE_CHAIN (fn))
16061 if (! DECL_ARTIFICIAL (fn))
16062 instantiate_decl (fn,
16064 /*expl_inst_class_mem_p=*/false);
16065 if (COMPLETE_TYPE_P (instantiation))
16069 complete = COMPLETE_TYPE_P (instantiation);
16073 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
16074 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
16077 = instantiate_decl (instantiation,
16079 /*expl_inst_class_mem_p=*/false);
16080 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
16084 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
16085 || DECL_TEMPLATE_INSTANTIATED (instantiation));
16089 /* If INSTANTIATION has been instantiated, then we don't
16090 need to consider it again in the future. */
16098 current_tinst_level = NULL;
16100 last_pending_template = last;
16102 while (reconsider);
16104 input_location = saved_loc;
16107 /* Substitute ARGVEC into T, which is a list of initializers for
16108 either base class or a non-static data member. The TREE_PURPOSEs
16109 are DECLs, and the TREE_VALUEs are the initializer values. Used by
16110 instantiate_decl. */
16113 tsubst_initializer_list (tree t, tree argvec)
16115 tree inits = NULL_TREE;
16117 for (; t; t = TREE_CHAIN (t))
16121 tree expanded_bases = NULL_TREE;
16122 tree expanded_arguments = NULL_TREE;
16125 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
16130 /* Expand the base class expansion type into separate base
16132 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
16133 tf_warning_or_error,
16135 if (expanded_bases == error_mark_node)
16138 /* We'll be building separate TREE_LISTs of arguments for
16140 len = TREE_VEC_LENGTH (expanded_bases);
16141 expanded_arguments = make_tree_vec (len);
16142 for (i = 0; i < len; i++)
16143 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
16145 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
16146 expand each argument in the TREE_VALUE of t. */
16147 expr = make_node (EXPR_PACK_EXPANSION);
16148 PACK_EXPANSION_PARAMETER_PACKS (expr) =
16149 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
16151 if (TREE_VALUE (t) == void_type_node)
16152 /* VOID_TYPE_NODE is used to indicate
16153 value-initialization. */
16155 for (i = 0; i < len; i++)
16156 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
16160 /* Substitute parameter packs into each argument in the
16162 in_base_initializer = 1;
16163 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
16165 tree expanded_exprs;
16167 /* Expand the argument. */
16168 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
16170 = tsubst_pack_expansion (expr, argvec,
16171 tf_warning_or_error,
16173 if (expanded_exprs == error_mark_node)
16176 /* Prepend each of the expanded expressions to the
16177 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
16178 for (i = 0; i < len; i++)
16180 TREE_VEC_ELT (expanded_arguments, i) =
16181 tree_cons (NULL_TREE,
16182 TREE_VEC_ELT (expanded_exprs, i),
16183 TREE_VEC_ELT (expanded_arguments, i));
16186 in_base_initializer = 0;
16188 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
16189 since we built them backwards. */
16190 for (i = 0; i < len; i++)
16192 TREE_VEC_ELT (expanded_arguments, i) =
16193 nreverse (TREE_VEC_ELT (expanded_arguments, i));
16198 for (i = 0; i < len; ++i)
16200 if (expanded_bases)
16202 decl = TREE_VEC_ELT (expanded_bases, i);
16203 decl = expand_member_init (decl);
16204 init = TREE_VEC_ELT (expanded_arguments, i);
16208 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
16209 tf_warning_or_error, NULL_TREE);
16211 decl = expand_member_init (decl);
16212 if (decl && !DECL_P (decl))
16213 in_base_initializer = 1;
16215 init = tsubst_expr (TREE_VALUE (t), argvec,
16216 tf_warning_or_error, NULL_TREE,
16217 /*integral_constant_expression_p=*/false);
16218 in_base_initializer = 0;
16223 init = build_tree_list (decl, init);
16224 TREE_CHAIN (init) = inits;
16232 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
16235 set_current_access_from_decl (tree decl)
16237 if (TREE_PRIVATE (decl))
16238 current_access_specifier = access_private_node;
16239 else if (TREE_PROTECTED (decl))
16240 current_access_specifier = access_protected_node;
16242 current_access_specifier = access_public_node;
16245 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
16246 is the instantiation (which should have been created with
16247 start_enum) and ARGS are the template arguments to use. */
16250 tsubst_enum (tree tag, tree newtag, tree args)
16254 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
16259 decl = TREE_VALUE (e);
16260 /* Note that in a template enum, the TREE_VALUE is the
16261 CONST_DECL, not the corresponding INTEGER_CST. */
16262 value = tsubst_expr (DECL_INITIAL (decl),
16263 args, tf_warning_or_error, NULL_TREE,
16264 /*integral_constant_expression_p=*/true);
16266 /* Give this enumeration constant the correct access. */
16267 set_current_access_from_decl (decl);
16269 /* Actually build the enumerator itself. */
16270 build_enumerator (DECL_NAME (decl), value, newtag);
16273 finish_enum (newtag);
16274 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
16275 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
16278 /* DECL is a FUNCTION_DECL that is a template specialization. Return
16279 its type -- but without substituting the innermost set of template
16280 arguments. So, innermost set of template parameters will appear in
16284 get_mostly_instantiated_function_type (tree decl)
16292 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
16293 targs = DECL_TI_ARGS (decl);
16294 tparms = DECL_TEMPLATE_PARMS (tmpl);
16295 parm_depth = TMPL_PARMS_DEPTH (tparms);
16297 /* There should be as many levels of arguments as there are levels
16299 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
16301 fn_type = TREE_TYPE (tmpl);
16303 if (parm_depth == 1)
16304 /* No substitution is necessary. */
16308 int i, save_access_control;
16311 /* Replace the innermost level of the TARGS with NULL_TREEs to
16312 let tsubst know not to substitute for those parameters. */
16313 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
16314 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
16315 SET_TMPL_ARGS_LEVEL (partial_args, i,
16316 TMPL_ARGS_LEVEL (targs, i));
16317 SET_TMPL_ARGS_LEVEL (partial_args,
16318 TMPL_ARGS_DEPTH (targs),
16319 make_tree_vec (DECL_NTPARMS (tmpl)));
16321 /* Disable access control as this function is used only during
16323 save_access_control = flag_access_control;
16324 flag_access_control = 0;
16326 ++processing_template_decl;
16327 /* Now, do the (partial) substitution to figure out the
16328 appropriate function type. */
16329 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
16330 --processing_template_decl;
16332 /* Substitute into the template parameters to obtain the real
16333 innermost set of parameters. This step is important if the
16334 innermost set of template parameters contains value
16335 parameters whose types depend on outer template parameters. */
16336 TREE_VEC_LENGTH (partial_args)--;
16337 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
16339 flag_access_control = save_access_control;
16345 /* Return truthvalue if we're processing a template different from
16346 the last one involved in diagnostics. */
16348 problematic_instantiation_changed (void)
16350 return last_template_error_tick != tinst_level_tick;
16353 /* Remember current template involved in diagnostics. */
16355 record_last_problematic_instantiation (void)
16357 last_template_error_tick = tinst_level_tick;
16360 struct tinst_level *
16361 current_instantiation (void)
16363 return current_tinst_level;
16366 /* [temp.param] Check that template non-type parm TYPE is of an allowable
16367 type. Return zero for ok, nonzero for disallowed. Issue error and
16368 warning messages under control of COMPLAIN. */
16371 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
16373 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
16375 else if (POINTER_TYPE_P (type))
16377 else if (TYPE_PTR_TO_MEMBER_P (type))
16379 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
16381 else if (TREE_CODE (type) == TYPENAME_TYPE)
16384 if (complain & tf_error)
16385 error ("%q#T is not a valid type for a template constant parameter", type);
16389 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
16390 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
16393 dependent_type_p_r (tree type)
16399 A type is dependent if it is:
16401 -- a template parameter. Template template parameters are types
16402 for us (since TYPE_P holds true for them) so we handle
16404 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
16405 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
16407 /* -- a qualified-id with a nested-name-specifier which contains a
16408 class-name that names a dependent type or whose unqualified-id
16409 names a dependent type. */
16410 if (TREE_CODE (type) == TYPENAME_TYPE)
16412 /* -- a cv-qualified type where the cv-unqualified type is
16414 type = TYPE_MAIN_VARIANT (type);
16415 /* -- a compound type constructed from any dependent type. */
16416 if (TYPE_PTR_TO_MEMBER_P (type))
16417 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
16418 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
16420 else if (TREE_CODE (type) == POINTER_TYPE
16421 || TREE_CODE (type) == REFERENCE_TYPE)
16422 return dependent_type_p (TREE_TYPE (type));
16423 else if (TREE_CODE (type) == FUNCTION_TYPE
16424 || TREE_CODE (type) == METHOD_TYPE)
16428 if (dependent_type_p (TREE_TYPE (type)))
16430 for (arg_type = TYPE_ARG_TYPES (type);
16432 arg_type = TREE_CHAIN (arg_type))
16433 if (dependent_type_p (TREE_VALUE (arg_type)))
16437 /* -- an array type constructed from any dependent type or whose
16438 size is specified by a constant expression that is
16439 value-dependent. */
16440 if (TREE_CODE (type) == ARRAY_TYPE)
16442 if (TYPE_DOMAIN (type)
16443 && dependent_type_p (TYPE_DOMAIN (type)))
16445 return dependent_type_p (TREE_TYPE (type));
16447 else if (TREE_CODE (type) == INTEGER_TYPE
16448 && !TREE_CONSTANT (TYPE_MAX_VALUE (type)))
16450 /* If this is the TYPE_DOMAIN of an array type, consider it
16451 dependent. We already checked for value-dependence in
16452 compute_array_index_type. */
16453 return type_dependent_expression_p (TYPE_MAX_VALUE (type));
16456 /* -- a template-id in which either the template name is a template
16458 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
16460 /* ... or any of the template arguments is a dependent type or
16461 an expression that is type-dependent or value-dependent. */
16462 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
16463 && (any_dependent_template_arguments_p
16464 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
16467 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
16468 argument of the `typeof' expression is not type-dependent, then
16469 it should already been have resolved. */
16470 if (TREE_CODE (type) == TYPEOF_TYPE
16471 || TREE_CODE (type) == DECLTYPE_TYPE)
16474 /* A template argument pack is dependent if any of its packed
16476 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
16478 tree args = ARGUMENT_PACK_ARGS (type);
16479 int i, len = TREE_VEC_LENGTH (args);
16480 for (i = 0; i < len; ++i)
16481 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
16485 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
16486 be template parameters. */
16487 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
16490 /* The standard does not specifically mention types that are local
16491 to template functions or local classes, but they should be
16492 considered dependent too. For example:
16494 template <int I> void f() {
16499 The size of `E' cannot be known until the value of `I' has been
16500 determined. Therefore, `E' must be considered dependent. */
16501 scope = TYPE_CONTEXT (type);
16502 if (scope && TYPE_P (scope))
16503 return dependent_type_p (scope);
16504 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
16505 return type_dependent_expression_p (scope);
16507 /* Other types are non-dependent. */
16511 /* Returns TRUE if TYPE is dependent, in the sense of
16512 [temp.dep.type]. */
16515 dependent_type_p (tree type)
16517 /* If there are no template parameters in scope, then there can't be
16518 any dependent types. */
16519 if (!processing_template_decl)
16521 /* If we are not processing a template, then nobody should be
16522 providing us with a dependent type. */
16524 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
16528 /* If the type is NULL, we have not computed a type for the entity
16529 in question; in that case, the type is dependent. */
16533 /* Erroneous types can be considered non-dependent. */
16534 if (type == error_mark_node)
16537 /* If we have not already computed the appropriate value for TYPE,
16539 if (!TYPE_DEPENDENT_P_VALID (type))
16541 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
16542 TYPE_DEPENDENT_P_VALID (type) = 1;
16545 return TYPE_DEPENDENT_P (type);
16548 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
16549 lookup. In other words, a dependent type that is not the current
16553 dependent_scope_p (tree scope)
16555 return (scope && TYPE_P (scope) && dependent_type_p (scope)
16556 && !currently_open_class (scope));
16559 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
16562 dependent_scope_ref_p (tree expression, bool criterion (tree))
16567 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
16569 if (!TYPE_P (TREE_OPERAND (expression, 0)))
16572 scope = TREE_OPERAND (expression, 0);
16573 name = TREE_OPERAND (expression, 1);
16577 An id-expression is type-dependent if it contains a
16578 nested-name-specifier that contains a class-name that names a
16580 /* The suggested resolution to Core Issue 224 implies that if the
16581 qualifying type is the current class, then we must peek
16584 && currently_open_class (scope)
16585 && !criterion (name))
16587 if (dependent_type_p (scope))
16593 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
16594 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
16598 value_dependent_expression_p (tree expression)
16600 if (!processing_template_decl)
16603 /* A name declared with a dependent type. */
16604 if (DECL_P (expression) && type_dependent_expression_p (expression))
16607 switch (TREE_CODE (expression))
16609 case IDENTIFIER_NODE:
16610 /* A name that has not been looked up -- must be dependent. */
16613 case TEMPLATE_PARM_INDEX:
16614 /* A non-type template parm. */
16618 /* A non-type template parm. */
16619 if (DECL_TEMPLATE_PARM_P (expression))
16621 return value_dependent_expression_p (DECL_INITIAL (expression));
16624 /* A constant with integral or enumeration type and is initialized
16625 with an expression that is value-dependent. */
16626 if (DECL_INITIAL (expression)
16627 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
16628 && value_dependent_expression_p (DECL_INITIAL (expression)))
16632 case DYNAMIC_CAST_EXPR:
16633 case STATIC_CAST_EXPR:
16634 case CONST_CAST_EXPR:
16635 case REINTERPRET_CAST_EXPR:
16637 /* These expressions are value-dependent if the type to which
16638 the cast occurs is dependent or the expression being casted
16639 is value-dependent. */
16641 tree type = TREE_TYPE (expression);
16643 if (dependent_type_p (type))
16646 /* A functional cast has a list of operands. */
16647 expression = TREE_OPERAND (expression, 0);
16650 /* If there are no operands, it must be an expression such
16651 as "int()". This should not happen for aggregate types
16652 because it would form non-constant expressions. */
16653 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
16658 if (TREE_CODE (expression) == TREE_LIST)
16659 return any_value_dependent_elements_p (expression);
16661 return value_dependent_expression_p (expression);
16666 /* A `sizeof' expression is value-dependent if the operand is
16667 type-dependent or is a pack expansion. */
16668 expression = TREE_OPERAND (expression, 0);
16669 if (PACK_EXPANSION_P (expression))
16671 else if (TYPE_P (expression))
16672 return dependent_type_p (expression);
16673 return type_dependent_expression_p (expression);
16676 return dependent_scope_ref_p (expression, value_dependent_expression_p);
16678 case COMPONENT_REF:
16679 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
16680 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
16683 /* A CALL_EXPR may appear in a constant expression if it is a
16684 call to a builtin function, e.g., __builtin_constant_p. All
16685 such calls are value-dependent. */
16688 case NONTYPE_ARGUMENT_PACK:
16689 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
16690 is value-dependent. */
16692 tree values = ARGUMENT_PACK_ARGS (expression);
16693 int i, len = TREE_VEC_LENGTH (values);
16695 for (i = 0; i < len; ++i)
16696 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
16704 tree type2 = TRAIT_EXPR_TYPE2 (expression);
16705 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
16706 || (type2 ? dependent_type_p (type2) : false));
16710 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
16711 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
16714 /* A constant expression is value-dependent if any subexpression is
16715 value-dependent. */
16716 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
16718 case tcc_reference:
16720 return (value_dependent_expression_p
16721 (TREE_OPERAND (expression, 0)));
16723 case tcc_comparison:
16725 return ((value_dependent_expression_p
16726 (TREE_OPERAND (expression, 0)))
16727 || (value_dependent_expression_p
16728 (TREE_OPERAND (expression, 1))));
16730 case tcc_expression:
16734 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
16735 /* In some cases, some of the operands may be missing.
16736 (For example, in the case of PREDECREMENT_EXPR, the
16737 amount to increment by may be missing.) That doesn't
16738 make the expression dependent. */
16739 if (TREE_OPERAND (expression, i)
16740 && (value_dependent_expression_p
16741 (TREE_OPERAND (expression, i))))
16751 /* The expression is not value-dependent. */
16755 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
16756 [temp.dep.expr]. */
16759 type_dependent_expression_p (tree expression)
16761 if (!processing_template_decl)
16764 if (expression == error_mark_node)
16767 /* An unresolved name is always dependent. */
16768 if (TREE_CODE (expression) == IDENTIFIER_NODE
16769 || TREE_CODE (expression) == USING_DECL)
16772 /* Some expression forms are never type-dependent. */
16773 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
16774 || TREE_CODE (expression) == SIZEOF_EXPR
16775 || TREE_CODE (expression) == ALIGNOF_EXPR
16776 || TREE_CODE (expression) == TRAIT_EXPR
16777 || TREE_CODE (expression) == TYPEID_EXPR
16778 || TREE_CODE (expression) == DELETE_EXPR
16779 || TREE_CODE (expression) == VEC_DELETE_EXPR
16780 || TREE_CODE (expression) == THROW_EXPR)
16783 /* The types of these expressions depends only on the type to which
16784 the cast occurs. */
16785 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
16786 || TREE_CODE (expression) == STATIC_CAST_EXPR
16787 || TREE_CODE (expression) == CONST_CAST_EXPR
16788 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
16789 || TREE_CODE (expression) == CAST_EXPR)
16790 return dependent_type_p (TREE_TYPE (expression));
16792 /* The types of these expressions depends only on the type created
16793 by the expression. */
16794 if (TREE_CODE (expression) == NEW_EXPR
16795 || TREE_CODE (expression) == VEC_NEW_EXPR)
16797 /* For NEW_EXPR tree nodes created inside a template, either
16798 the object type itself or a TREE_LIST may appear as the
16800 tree type = TREE_OPERAND (expression, 1);
16801 if (TREE_CODE (type) == TREE_LIST)
16802 /* This is an array type. We need to check array dimensions
16804 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
16805 || value_dependent_expression_p
16806 (TREE_OPERAND (TREE_VALUE (type), 1));
16808 return dependent_type_p (type);
16811 if (TREE_CODE (expression) == SCOPE_REF
16812 && dependent_scope_ref_p (expression,
16813 type_dependent_expression_p))
16816 if (TREE_CODE (expression) == FUNCTION_DECL
16817 && DECL_LANG_SPECIFIC (expression)
16818 && DECL_TEMPLATE_INFO (expression)
16819 && (any_dependent_template_arguments_p
16820 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
16823 if (TREE_CODE (expression) == TEMPLATE_DECL
16824 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
16827 if (TREE_CODE (expression) == STMT_EXPR)
16828 expression = stmt_expr_value_expr (expression);
16830 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
16835 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
16837 if (type_dependent_expression_p (elt))
16843 if (TREE_TYPE (expression) == unknown_type_node)
16845 if (TREE_CODE (expression) == ADDR_EXPR)
16846 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
16847 if (TREE_CODE (expression) == COMPONENT_REF
16848 || TREE_CODE (expression) == OFFSET_REF)
16850 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
16852 expression = TREE_OPERAND (expression, 1);
16853 if (TREE_CODE (expression) == IDENTIFIER_NODE)
16856 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
16857 if (TREE_CODE (expression) == SCOPE_REF)
16860 if (TREE_CODE (expression) == BASELINK)
16861 expression = BASELINK_FUNCTIONS (expression);
16863 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
16865 if (any_dependent_template_arguments_p
16866 (TREE_OPERAND (expression, 1)))
16868 expression = TREE_OPERAND (expression, 0);
16870 gcc_assert (TREE_CODE (expression) == OVERLOAD
16871 || TREE_CODE (expression) == FUNCTION_DECL);
16875 if (type_dependent_expression_p (OVL_CURRENT (expression)))
16877 expression = OVL_NEXT (expression);
16882 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
16884 return (dependent_type_p (TREE_TYPE (expression)));
16887 /* Like type_dependent_expression_p, but it also works while not processing
16888 a template definition, i.e. during substitution or mangling. */
16891 type_dependent_expression_p_push (tree expr)
16894 ++processing_template_decl;
16895 b = type_dependent_expression_p (expr);
16896 --processing_template_decl;
16900 /* Returns TRUE if ARGS contains a type-dependent expression. */
16903 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
16908 for (i = 0; VEC_iterate (tree, args, i, arg); ++i)
16910 if (type_dependent_expression_p (arg))
16916 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
16917 expressions) contains any value-dependent expressions. */
16920 any_value_dependent_elements_p (const_tree list)
16922 for (; list; list = TREE_CHAIN (list))
16923 if (value_dependent_expression_p (TREE_VALUE (list)))
16929 /* Returns TRUE if the ARG (a template argument) is dependent. */
16932 dependent_template_arg_p (tree arg)
16934 if (!processing_template_decl)
16937 if (TREE_CODE (arg) == TEMPLATE_DECL
16938 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
16939 return dependent_template_p (arg);
16940 else if (ARGUMENT_PACK_P (arg))
16942 tree args = ARGUMENT_PACK_ARGS (arg);
16943 int i, len = TREE_VEC_LENGTH (args);
16944 for (i = 0; i < len; ++i)
16946 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
16952 else if (TYPE_P (arg))
16953 return dependent_type_p (arg);
16955 return (type_dependent_expression_p (arg)
16956 || value_dependent_expression_p (arg));
16959 /* Returns true if ARGS (a collection of template arguments) contains
16960 any types that require structural equality testing. */
16963 any_template_arguments_need_structural_equality_p (tree args)
16970 if (args == error_mark_node)
16973 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
16975 tree level = TMPL_ARGS_LEVEL (args, i + 1);
16976 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
16978 tree arg = TREE_VEC_ELT (level, j);
16979 tree packed_args = NULL_TREE;
16982 if (ARGUMENT_PACK_P (arg))
16984 /* Look inside the argument pack. */
16985 packed_args = ARGUMENT_PACK_ARGS (arg);
16986 len = TREE_VEC_LENGTH (packed_args);
16989 for (k = 0; k < len; ++k)
16992 arg = TREE_VEC_ELT (packed_args, k);
16994 if (error_operand_p (arg))
16996 else if (TREE_CODE (arg) == TEMPLATE_DECL
16997 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
16999 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
17001 else if (!TYPE_P (arg) && TREE_TYPE (arg)
17002 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
17011 /* Returns true if ARGS (a collection of template arguments) contains
17012 any dependent arguments. */
17015 any_dependent_template_arguments_p (const_tree args)
17022 if (args == error_mark_node)
17025 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17027 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
17028 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17029 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
17036 /* Returns TRUE if the template TMPL is dependent. */
17039 dependent_template_p (tree tmpl)
17041 if (TREE_CODE (tmpl) == OVERLOAD)
17045 if (dependent_template_p (OVL_FUNCTION (tmpl)))
17047 tmpl = OVL_CHAIN (tmpl);
17052 /* Template template parameters are dependent. */
17053 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
17054 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
17056 /* So are names that have not been looked up. */
17057 if (TREE_CODE (tmpl) == SCOPE_REF
17058 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
17060 /* So are member templates of dependent classes. */
17061 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
17062 return dependent_type_p (DECL_CONTEXT (tmpl));
17066 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
17069 dependent_template_id_p (tree tmpl, tree args)
17071 return (dependent_template_p (tmpl)
17072 || any_dependent_template_arguments_p (args));
17075 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
17079 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
17083 if (!processing_template_decl)
17086 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
17088 tree decl = TREE_VEC_ELT (declv, i);
17089 tree init = TREE_VEC_ELT (initv, i);
17090 tree cond = TREE_VEC_ELT (condv, i);
17091 tree incr = TREE_VEC_ELT (incrv, i);
17093 if (type_dependent_expression_p (decl))
17096 if (init && type_dependent_expression_p (init))
17099 if (type_dependent_expression_p (cond))
17102 if (COMPARISON_CLASS_P (cond)
17103 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
17104 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
17107 if (TREE_CODE (incr) == MODOP_EXPR)
17109 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
17110 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
17113 else if (type_dependent_expression_p (incr))
17115 else if (TREE_CODE (incr) == MODIFY_EXPR)
17117 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
17119 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
17121 tree t = TREE_OPERAND (incr, 1);
17122 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
17123 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
17132 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
17133 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
17134 no such TYPE can be found. Note that this function peers inside
17135 uninstantiated templates and therefore should be used only in
17136 extremely limited situations. ONLY_CURRENT_P restricts this
17137 peering to the currently open classes hierarchy (which is required
17138 when comparing types). */
17141 resolve_typename_type (tree type, bool only_current_p)
17150 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
17152 scope = TYPE_CONTEXT (type);
17153 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
17154 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
17155 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
17156 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
17157 identifier of the TYPENAME_TYPE anymore.
17158 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
17159 TYPENAME_TYPE instead, we avoid messing up with a possible
17160 typedef variant case. */
17161 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
17163 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
17164 it first before we can figure out what NAME refers to. */
17165 if (TREE_CODE (scope) == TYPENAME_TYPE)
17166 scope = resolve_typename_type (scope, only_current_p);
17167 /* If we don't know what SCOPE refers to, then we cannot resolve the
17169 if (TREE_CODE (scope) == TYPENAME_TYPE)
17171 /* If the SCOPE is a template type parameter, we have no way of
17172 resolving the name. */
17173 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
17175 /* If the SCOPE is not the current instantiation, there's no reason
17176 to look inside it. */
17177 if (only_current_p && !currently_open_class (scope))
17179 /* If SCOPE isn't the template itself, it will not have a valid
17180 TYPE_FIELDS list. */
17181 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
17182 /* scope is either the template itself or a compatible instantiation
17183 like X<T>, so look up the name in the original template. */
17184 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
17186 /* scope is a partial instantiation, so we can't do the lookup or we
17187 will lose the template arguments. */
17189 /* Enter the SCOPE so that name lookup will be resolved as if we
17190 were in the class definition. In particular, SCOPE will no
17191 longer be considered a dependent type. */
17192 pushed_scope = push_scope (scope);
17193 /* Look up the declaration. */
17194 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
17196 result = NULL_TREE;
17198 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
17199 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
17202 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
17203 && TREE_CODE (decl) == TYPE_DECL)
17205 result = TREE_TYPE (decl);
17206 if (result == error_mark_node)
17207 result = NULL_TREE;
17209 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
17210 && DECL_CLASS_TEMPLATE_P (decl))
17214 /* Obtain the template and the arguments. */
17215 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
17216 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
17217 /* Instantiate the template. */
17218 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
17219 /*entering_scope=*/0,
17220 tf_error | tf_user);
17221 if (result == error_mark_node)
17222 result = NULL_TREE;
17225 /* Leave the SCOPE. */
17227 pop_scope (pushed_scope);
17229 /* If we failed to resolve it, return the original typename. */
17233 /* If lookup found a typename type, resolve that too. */
17234 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
17236 /* Ill-formed programs can cause infinite recursion here, so we
17237 must catch that. */
17238 TYPENAME_IS_RESOLVING_P (type) = 1;
17239 result = resolve_typename_type (result, only_current_p);
17240 TYPENAME_IS_RESOLVING_P (type) = 0;
17243 /* Qualify the resulting type. */
17244 quals = cp_type_quals (type);
17246 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
17251 /* EXPR is an expression which is not type-dependent. Return a proxy
17252 for EXPR that can be used to compute the types of larger
17253 expressions containing EXPR. */
17256 build_non_dependent_expr (tree expr)
17260 /* Preserve null pointer constants so that the type of things like
17261 "p == 0" where "p" is a pointer can be determined. */
17262 if (null_ptr_cst_p (expr))
17264 /* Preserve OVERLOADs; the functions must be available to resolve
17267 if (TREE_CODE (inner_expr) == STMT_EXPR)
17268 inner_expr = stmt_expr_value_expr (inner_expr);
17269 if (TREE_CODE (inner_expr) == ADDR_EXPR)
17270 inner_expr = TREE_OPERAND (inner_expr, 0);
17271 if (TREE_CODE (inner_expr) == COMPONENT_REF)
17272 inner_expr = TREE_OPERAND (inner_expr, 1);
17273 if (is_overloaded_fn (inner_expr)
17274 || TREE_CODE (inner_expr) == OFFSET_REF)
17276 /* There is no need to return a proxy for a variable. */
17277 if (TREE_CODE (expr) == VAR_DECL)
17279 /* Preserve string constants; conversions from string constants to
17280 "char *" are allowed, even though normally a "const char *"
17281 cannot be used to initialize a "char *". */
17282 if (TREE_CODE (expr) == STRING_CST)
17284 /* Preserve arithmetic constants, as an optimization -- there is no
17285 reason to create a new node. */
17286 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
17288 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
17289 There is at least one place where we want to know that a
17290 particular expression is a throw-expression: when checking a ?:
17291 expression, there are special rules if the second or third
17292 argument is a throw-expression. */
17293 if (TREE_CODE (expr) == THROW_EXPR)
17296 if (TREE_CODE (expr) == COND_EXPR)
17297 return build3 (COND_EXPR,
17299 TREE_OPERAND (expr, 0),
17300 (TREE_OPERAND (expr, 1)
17301 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
17302 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
17303 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
17304 if (TREE_CODE (expr) == COMPOUND_EXPR
17305 && !COMPOUND_EXPR_OVERLOADED (expr))
17306 return build2 (COMPOUND_EXPR,
17308 TREE_OPERAND (expr, 0),
17309 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
17311 /* If the type is unknown, it can't really be non-dependent */
17312 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
17314 /* Otherwise, build a NON_DEPENDENT_EXPR.
17316 REFERENCE_TYPEs are not stripped for expressions in templates
17317 because doing so would play havoc with mangling. Consider, for
17320 template <typename T> void f<T& g>() { g(); }
17322 In the body of "f", the expression for "g" will have
17323 REFERENCE_TYPE, even though the standard says that it should
17324 not. The reason is that we must preserve the syntactic form of
17325 the expression so that mangling (say) "f<g>" inside the body of
17326 "f" works out correctly. Therefore, the REFERENCE_TYPE is
17328 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
17331 /* ARGS is a vector of expressions as arguments to a function call.
17332 Replace the arguments with equivalent non-dependent expressions.
17333 This modifies ARGS in place. */
17336 make_args_non_dependent (VEC(tree,gc) *args)
17341 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
17343 tree newarg = build_non_dependent_expr (arg);
17345 VEC_replace (tree, args, ix, newarg);
17349 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
17350 with a level one deeper than the actual template parms. */
17357 /* ??? Is it worth caching this for multiple autos at the same level? */
17358 au = cxx_make_type (TEMPLATE_TYPE_PARM);
17359 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
17360 TYPE_DECL, get_identifier ("auto"), au);
17361 TYPE_STUB_DECL (au) = TYPE_NAME (au);
17362 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
17363 (0, processing_template_decl + 1, processing_template_decl + 1,
17364 TYPE_NAME (au), NULL_TREE);
17365 TYPE_CANONICAL (au) = canonical_type_parameter (au);
17366 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
17367 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
17372 /* Replace auto in TYPE with std::initializer_list<auto>. */
17375 listify_autos (tree type, tree auto_node)
17377 tree std_init_list = namespace_binding
17378 (get_identifier ("initializer_list"), std_node);
17381 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
17383 error ("deducing auto from brace-enclosed initializer list requires "
17384 "#include <initializer_list>");
17385 return error_mark_node;
17387 argvec = make_tree_vec (1);
17388 TREE_VEC_ELT (argvec, 0) = auto_node;
17389 init_auto = lookup_template_class (std_init_list, argvec, NULL_TREE,
17390 NULL_TREE, 0, tf_warning_or_error);
17392 TREE_VEC_ELT (argvec, 0) = init_auto;
17393 if (processing_template_decl)
17394 argvec = add_to_template_args (current_template_args (), argvec);
17395 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
17398 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
17399 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
17402 do_auto_deduction (tree type, tree init, tree auto_node)
17404 tree parms, tparms, targs;
17408 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
17409 with either a new invented type template parameter U or, if the
17410 initializer is a braced-init-list (8.5.4), with
17411 std::initializer_list<U>. */
17412 if (BRACE_ENCLOSED_INITIALIZER_P (init))
17413 type = listify_autos (type, auto_node);
17415 parms = build_tree_list (NULL_TREE, type);
17417 tparms = make_tree_vec (1);
17418 targs = make_tree_vec (1);
17419 TREE_VEC_ELT (tparms, 0)
17420 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
17421 val = type_unification_real (tparms, targs, parms, args, 1, 0,
17422 DEDUCE_CALL, LOOKUP_NORMAL);
17425 error ("unable to deduce %qT from %qE", type, init);
17426 return error_mark_node;
17429 if (processing_template_decl)
17430 targs = add_to_template_args (current_template_args (), targs);
17431 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
17434 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
17438 splice_late_return_type (tree type, tree late_return_type)
17442 if (late_return_type == NULL_TREE)
17444 argvec = make_tree_vec (1);
17445 TREE_VEC_ELT (argvec, 0) = late_return_type;
17446 if (processing_template_decl)
17447 argvec = add_to_template_args (current_template_args (), argvec);
17448 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
17451 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
17454 is_auto (const_tree type)
17456 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
17457 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
17463 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
17464 appear as a type-specifier for the declaration in question, we don't
17465 have to look through the whole type. */
17468 type_uses_auto (tree type)
17470 enum tree_code code;
17471 if (is_auto (type))
17474 code = TREE_CODE (type);
17476 if (code == POINTER_TYPE || code == REFERENCE_TYPE
17477 || code == OFFSET_TYPE || code == FUNCTION_TYPE
17478 || code == METHOD_TYPE || code == ARRAY_TYPE)
17479 return type_uses_auto (TREE_TYPE (type));
17481 if (TYPE_PTRMEMFUNC_P (type))
17482 return type_uses_auto (TREE_TYPE (TREE_TYPE
17483 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
17488 /* For a given template T, return the list of typedefs referenced
17489 in T for which access check is needed at T instantiation time.
17490 T is either a FUNCTION_DECL or a RECORD_TYPE.
17491 Those typedefs were added to T by the function
17492 append_type_to_template_for_access_check. */
17495 get_types_needing_access_check (tree t)
17497 tree ti, result = NULL_TREE;
17499 if (!t || t == error_mark_node)
17502 if (!(ti = get_template_info (t)))
17505 if (CLASS_TYPE_P (t)
17506 || TREE_CODE (t) == FUNCTION_DECL)
17508 if (!TI_TEMPLATE (ti))
17511 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
17517 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
17518 tied to T. That list of typedefs will be access checked at
17519 T instantiation time.
17520 T is either a FUNCTION_DECL or a RECORD_TYPE.
17521 TYPE_DECL is a TYPE_DECL node representing a typedef.
17522 SCOPE is the scope through which TYPE_DECL is accessed.
17524 This function is a subroutine of
17525 append_type_to_template_for_access_check. */
17528 append_type_to_template_for_access_check_1 (tree t,
17534 if (!t || t == error_mark_node)
17537 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
17538 || CLASS_TYPE_P (t))
17540 && TREE_CODE (type_decl) == TYPE_DECL
17543 if (!(ti = get_template_info (t)))
17546 gcc_assert (TI_TEMPLATE (ti));
17548 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti) =
17549 tree_cons (type_decl, scope, TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti));
17552 /* Append TYPE_DECL to the template TEMPL.
17553 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
17554 At TEMPL instanciation time, TYPE_DECL will be checked to see
17555 if it can be accessed through SCOPE.
17557 e.g. consider the following code snippet:
17564 template<class U> struct S
17571 At S<char> instantiation time, we need to check the access of C::myint
17572 In other words, we need to check the access of the myint typedef through
17573 the C scope. For that purpose, this function will add the myint typedef
17574 and the scope C through which its being accessed to a list of typedefs
17575 tied to the template S. That list will be walked at template instantiation
17576 time and access check performed on each typedefs it contains.
17577 Note that this particular code snippet should yield an error because
17578 myint is private to C. */
17581 append_type_to_template_for_access_check (tree templ,
17587 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
17589 /* Make sure we don't append the type to the template twice. */
17590 for (node = get_types_needing_access_check (templ);
17592 node = TREE_CHAIN (node))
17594 tree decl = TREE_PURPOSE (node);
17595 tree type_scope = TREE_VALUE (node);
17597 if (decl == type_decl && type_scope == scope)
17601 append_type_to_template_for_access_check_1 (templ, type_decl, scope);
17604 /* Set up the hash tables for template instantiations. */
17607 init_template_processing (void)
17609 decl_specializations = htab_create_ggc (37,
17610 hash_specialization,
17611 eq_specializations,
17613 type_specializations = htab_create_ggc (37,
17614 hash_specialization,
17615 eq_specializations,
17619 #include "gt-cp-pt.h"