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)
986 htab_t specializations;
990 elt.spec = NULL_TREE;
992 if (DECL_CLASS_TEMPLATE_P (tmpl))
993 specializations = type_specializations;
995 specializations = decl_specializations;
998 hash = hash_specialization (&elt);
999 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash);
1007 /* Like retrieve_specialization, but for local declarations. */
1010 retrieve_local_specialization (tree tmpl)
1014 if (local_specializations == NULL)
1017 spec = (tree) htab_find_with_hash (local_specializations, tmpl,
1018 htab_hash_pointer (tmpl));
1019 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
1022 /* Returns nonzero iff DECL is a specialization of TMPL. */
1025 is_specialization_of (tree decl, tree tmpl)
1029 if (TREE_CODE (decl) == FUNCTION_DECL)
1033 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
1039 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
1041 for (t = TREE_TYPE (decl);
1043 t = CLASSTYPE_USE_TEMPLATE (t)
1044 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
1045 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
1052 /* Returns nonzero iff DECL is a specialization of friend declaration
1053 FRIEND_DECL according to [temp.friend]. */
1056 is_specialization_of_friend (tree decl, tree friend_decl)
1058 bool need_template = true;
1061 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
1062 || TREE_CODE (decl) == TYPE_DECL);
1064 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function
1065 of a template class, we want to check if DECL is a specialization
1067 if (TREE_CODE (friend_decl) == FUNCTION_DECL
1068 && DECL_TEMPLATE_INFO (friend_decl)
1069 && !DECL_USE_TEMPLATE (friend_decl))
1071 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
1072 friend_decl = DECL_TI_TEMPLATE (friend_decl);
1073 need_template = false;
1075 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL
1076 && !PRIMARY_TEMPLATE_P (friend_decl))
1077 need_template = false;
1079 /* There is nothing to do if this is not a template friend. */
1080 if (TREE_CODE (friend_decl) != TEMPLATE_DECL)
1083 if (is_specialization_of (decl, friend_decl))
1087 A member of a class template may be declared to be a friend of a
1088 non-template class. In this case, the corresponding member of
1089 every specialization of the class template is a friend of the
1090 class granting friendship.
1092 For example, given a template friend declaration
1094 template <class T> friend void A<T>::f();
1096 the member function below is considered a friend
1098 template <> struct A<int> {
1102 For this type of template friend, TEMPLATE_DEPTH below will be
1103 nonzero. To determine if DECL is a friend of FRIEND, we first
1104 check if the enclosing class is a specialization of another. */
1106 template_depth = template_class_depth (DECL_CONTEXT (friend_decl));
1108 && DECL_CLASS_SCOPE_P (decl)
1109 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1110 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl))))
1112 /* Next, we check the members themselves. In order to handle
1113 a few tricky cases, such as when FRIEND_DECL's are
1115 template <class T> friend void A<T>::g(T t);
1116 template <class T> template <T t> friend void A<T>::h();
1120 void A<int>::g(int);
1121 template <int> void A<int>::h();
1123 we need to figure out ARGS, the template arguments from
1124 the context of DECL. This is required for template substitution
1125 of `T' in the function parameter of `g' and template parameter
1126 of `h' in the above examples. Here ARGS corresponds to `int'. */
1128 tree context = DECL_CONTEXT (decl);
1129 tree args = NULL_TREE;
1130 int current_depth = 0;
1132 while (current_depth < template_depth)
1134 if (CLASSTYPE_TEMPLATE_INFO (context))
1136 if (current_depth == 0)
1137 args = TYPE_TI_ARGS (context);
1139 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1142 context = TYPE_CONTEXT (context);
1145 if (TREE_CODE (decl) == FUNCTION_DECL)
1150 tree friend_args_type;
1151 tree decl_args_type;
1153 /* Make sure that both DECL and FRIEND_DECL are templates or
1155 is_template = DECL_TEMPLATE_INFO (decl)
1156 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1157 if (need_template ^ is_template)
1159 else if (is_template)
1161 /* If both are templates, check template parameter list. */
1163 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1165 if (!comp_template_parms
1166 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1170 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1173 decl_type = TREE_TYPE (decl);
1175 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args,
1176 tf_none, NULL_TREE);
1177 if (friend_type == error_mark_node)
1180 /* Check if return types match. */
1181 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1184 /* Check if function parameter types match, ignoring the
1185 `this' parameter. */
1186 friend_args_type = TYPE_ARG_TYPES (friend_type);
1187 decl_args_type = TYPE_ARG_TYPES (decl_type);
1188 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl))
1189 friend_args_type = TREE_CHAIN (friend_args_type);
1190 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1191 decl_args_type = TREE_CHAIN (decl_args_type);
1193 return compparms (decl_args_type, friend_args_type);
1197 /* DECL is a TYPE_DECL */
1199 tree decl_type = TREE_TYPE (decl);
1201 /* Make sure that both DECL and FRIEND_DECL are templates or
1204 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1205 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1207 if (need_template ^ is_template)
1209 else if (is_template)
1212 /* If both are templates, check the name of the two
1213 TEMPLATE_DECL's first because is_friend didn't. */
1214 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1215 != DECL_NAME (friend_decl))
1218 /* Now check template parameter list. */
1220 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl),
1222 return comp_template_parms
1223 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1227 return (DECL_NAME (decl)
1228 == DECL_NAME (friend_decl));
1234 /* Register the specialization SPEC as a specialization of TMPL with
1235 the indicated ARGS. IS_FRIEND indicates whether the specialization
1236 is actually just a friend declaration. Returns SPEC, or an
1237 equivalent prior declaration, if available. */
1240 register_specialization (tree spec, tree tmpl, tree args, bool is_friend,
1244 spec_entry **slot = NULL;
1247 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec));
1249 if (TREE_CODE (spec) == FUNCTION_DECL
1250 && uses_template_parms (DECL_TI_ARGS (spec)))
1251 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1252 register it; we want the corresponding TEMPLATE_DECL instead.
1253 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1254 the more obvious `uses_template_parms (spec)' to avoid problems
1255 with default function arguments. In particular, given
1256 something like this:
1258 template <class T> void f(T t1, T t = T())
1260 the default argument expression is not substituted for in an
1261 instantiation unless and until it is actually needed. */
1264 if (optimize_specialization_lookup_p (tmpl))
1265 /* We don't put these specializations in the hash table, but we might
1266 want to give an error about a mismatch. */
1267 fn = retrieve_specialization (tmpl, args, 0);
1275 hash = hash_specialization (&elt);
1277 slot = (spec_entry **)
1278 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT);
1285 /* We can sometimes try to re-register a specialization that we've
1286 already got. In particular, regenerate_decl_from_template calls
1287 duplicate_decls which will update the specialization list. But,
1288 we'll still get called again here anyhow. It's more convenient
1289 to simply allow this than to try to prevent it. */
1292 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1294 if (DECL_TEMPLATE_INSTANTIATION (fn))
1297 || DECL_EXPLICIT_INSTANTIATION (fn))
1299 error ("specialization of %qD after instantiation",
1301 return error_mark_node;
1306 /* This situation should occur only if the first
1307 specialization is an implicit instantiation, the
1308 second is an explicit specialization, and the
1309 implicit instantiation has not yet been used. That
1310 situation can occur if we have implicitly
1311 instantiated a member function and then specialized
1314 We can also wind up here if a friend declaration that
1315 looked like an instantiation turns out to be a
1318 template <class T> void foo(T);
1319 class S { friend void foo<>(int) };
1320 template <> void foo(int);
1322 We transform the existing DECL in place so that any
1323 pointers to it become pointers to the updated
1326 If there was a definition for the template, but not
1327 for the specialization, we want this to look as if
1328 there were no definition, and vice versa. */
1329 DECL_INITIAL (fn) = NULL_TREE;
1330 duplicate_decls (spec, fn, is_friend);
1331 /* The call to duplicate_decls will have applied
1334 An explicit specialization of a function template
1335 is inline only if it is explicitly declared to be,
1336 and independently of whether its function template
1339 to the primary function; now copy the inline bits to
1340 the various clones. */
1341 FOR_EACH_CLONE (clone, fn)
1342 DECL_DECLARED_INLINE_P (clone)
1343 = DECL_DECLARED_INLINE_P (fn);
1344 check_specialization_namespace (fn);
1349 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1351 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1352 /* Dup decl failed, but this is a new definition. Set the
1353 line number so any errors match this new
1355 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1361 return duplicate_decls (spec, fn, is_friend);
1363 /* A specialization must be declared in the same namespace as the
1364 template it is specializing. */
1365 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1366 && !check_specialization_namespace (tmpl))
1367 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl);
1369 if (!optimize_specialization_lookup_p (tmpl))
1371 gcc_assert (tmpl && args && spec);
1372 *slot = GGC_NEW (spec_entry);
1374 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec)
1375 && PRIMARY_TEMPLATE_P (tmpl)
1376 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE)
1377 /* TMPL is a forward declaration of a template function; keep a list
1378 of all specializations in case we need to reassign them to a friend
1379 template later in tsubst_friend_function. */
1380 DECL_TEMPLATE_INSTANTIATIONS (tmpl)
1381 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl));
1387 /* Returns true iff two spec_entry nodes are equivalent. Only compares the
1388 TMPL and ARGS members, ignores SPEC. */
1391 eq_specializations (const void *p1, const void *p2)
1393 const spec_entry *e1 = (const spec_entry *)p1;
1394 const spec_entry *e2 = (const spec_entry *)p2;
1396 return (e1->tmpl == e2->tmpl
1397 && comp_template_args (e1->args, e2->args));
1400 /* Returns a hash for a template TMPL and template arguments ARGS. */
1403 hash_tmpl_and_args (tree tmpl, tree args)
1405 hashval_t val = DECL_UID (tmpl);
1406 return iterative_hash_template_arg (args, val);
1409 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members,
1413 hash_specialization (const void *p)
1415 const spec_entry *e = (const spec_entry *)p;
1416 return hash_tmpl_and_args (e->tmpl, e->args);
1419 /* Recursively calculate a hash value for a template argument ARG, for use
1420 in the hash tables of template specializations. */
1423 iterative_hash_template_arg (tree arg, hashval_t val)
1425 unsigned HOST_WIDE_INT i;
1426 enum tree_code code;
1429 if (arg == NULL_TREE)
1430 return iterative_hash_object (arg, val);
1435 code = TREE_CODE (arg);
1436 tclass = TREE_CODE_CLASS (code);
1438 val = iterative_hash_object (code, val);
1445 case IDENTIFIER_NODE:
1446 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val);
1450 int i, len = TREE_VEC_LENGTH (arg);
1451 for (i = 0; i < len; ++i)
1452 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val);
1456 case TYPE_PACK_EXPANSION:
1457 case EXPR_PACK_EXPANSION:
1458 return iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val);
1460 case ARGUMENT_PACK_SELECT:
1461 /* We can get one of these when re-hashing a previous entry in the middle
1462 of substituting into a pack expansion. Just look through it... */
1463 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg);
1464 /* ...and fall through. */
1465 case TYPE_ARGUMENT_PACK:
1466 case NONTYPE_ARGUMENT_PACK:
1467 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val);
1470 for (; arg; arg = TREE_CHAIN (arg))
1471 val = iterative_hash_template_arg (TREE_VALUE (arg), val);
1475 for (; arg; arg = OVL_CHAIN (arg))
1476 val = iterative_hash_template_arg (OVL_FUNCTION (arg), val);
1482 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value)
1484 val = iterative_hash_template_arg (field, val);
1485 val = iterative_hash_template_arg (value, val);
1491 val = iterative_hash_object (DECL_PARM_INDEX (arg), val);
1492 return iterative_hash_template_arg (TREE_TYPE (arg), val);
1495 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val);
1498 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val);
1499 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val);
1501 case TEMPLATE_PARM_INDEX:
1502 val = iterative_hash_template_arg
1503 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val);
1504 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val);
1505 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val);
1508 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val);
1509 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val);
1510 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val);
1513 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)),
1515 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)),
1519 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val);
1520 code = TREE_CODE (TREE_OPERAND (arg, 1));
1521 val = iterative_hash_object (code, val);
1522 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val);
1528 if (TYPE_CANONICAL (arg))
1529 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)),
1531 else if (TREE_CODE (arg) == DECLTYPE_TYPE)
1532 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val);
1533 /* Otherwise just compare the types during lookup. */
1536 case tcc_declaration:
1538 return iterative_hash_expr (arg, val);
1541 gcc_assert (IS_EXPR_CODE_CLASS (tclass));
1543 unsigned n = TREE_OPERAND_LENGTH (arg);
1544 for (i = 0; i < n; ++i)
1545 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val);
1554 /* Unregister the specialization SPEC as a specialization of TMPL.
1555 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1556 if the SPEC was listed as a specialization of TMPL.
1558 Note that SPEC has been ggc_freed, so we can't look inside it. */
1561 reregister_specialization (tree spec, tree tinfo, tree new_spec)
1566 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo));
1567 elt.args = TI_ARGS (tinfo);
1568 elt.spec = NULL_TREE;
1570 slot = (spec_entry **) htab_find_slot (decl_specializations, &elt, INSERT);
1573 gcc_assert ((*slot)->spec == spec || (*slot)->spec == new_spec);
1574 gcc_assert (new_spec != NULL_TREE);
1575 (*slot)->spec = new_spec;
1582 /* Compare an entry in the local specializations hash table P1 (which
1583 is really a pointer to a TREE_LIST) with P2 (which is really a
1587 eq_local_specializations (const void *p1, const void *p2)
1589 return TREE_VALUE ((const_tree) p1) == (const_tree) p2;
1592 /* Hash P1, an entry in the local specializations table. */
1595 hash_local_specialization (const void* p1)
1597 return htab_hash_pointer (TREE_VALUE ((const_tree) p1));
1600 /* Like register_specialization, but for local declarations. We are
1601 registering SPEC, an instantiation of TMPL. */
1604 register_local_specialization (tree spec, tree tmpl)
1608 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1609 htab_hash_pointer (tmpl), INSERT);
1610 *slot = build_tree_list (spec, tmpl);
1613 /* TYPE is a class type. Returns true if TYPE is an explicitly
1614 specialized class. */
1617 explicit_class_specialization_p (tree type)
1619 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
1621 return !uses_template_parms (CLASSTYPE_TI_ARGS (type));
1624 /* Print the list of candidate FNS in an error message. */
1627 print_candidates (tree fns)
1631 const char *str = "candidates are:";
1633 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1637 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1638 error ("%s %+#D", str, OVL_CURRENT (f));
1643 /* Returns the template (one of the functions given by TEMPLATE_ID)
1644 which can be specialized to match the indicated DECL with the
1645 explicit template args given in TEMPLATE_ID. The DECL may be
1646 NULL_TREE if none is available. In that case, the functions in
1647 TEMPLATE_ID are non-members.
1649 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1650 specialization of a member template.
1652 The TEMPLATE_COUNT is the number of references to qualifying
1653 template classes that appeared in the name of the function. See
1654 check_explicit_specialization for a more accurate description.
1656 TSK indicates what kind of template declaration (if any) is being
1657 declared. TSK_TEMPLATE indicates that the declaration given by
1658 DECL, though a FUNCTION_DECL, has template parameters, and is
1659 therefore a template function.
1661 The template args (those explicitly specified and those deduced)
1662 are output in a newly created vector *TARGS_OUT.
1664 If it is impossible to determine the result, an error message is
1665 issued. The error_mark_node is returned to indicate failure. */
1668 determine_specialization (tree template_id,
1671 int need_member_template,
1677 tree explicit_targs;
1678 tree candidates = NULL_TREE;
1679 /* A TREE_LIST of templates of which DECL may be a specialization.
1680 The TREE_VALUE of each node is a TEMPLATE_DECL. The
1681 corresponding TREE_PURPOSE is the set of template arguments that,
1682 when used to instantiate the template, would produce a function
1683 with the signature of DECL. */
1684 tree templates = NULL_TREE;
1686 struct cp_binding_level *b;
1688 *targs_out = NULL_TREE;
1690 if (template_id == error_mark_node || decl == error_mark_node)
1691 return error_mark_node;
1693 fns = TREE_OPERAND (template_id, 0);
1694 explicit_targs = TREE_OPERAND (template_id, 1);
1696 if (fns == error_mark_node)
1697 return error_mark_node;
1699 /* Check for baselinks. */
1700 if (BASELINK_P (fns))
1701 fns = BASELINK_FUNCTIONS (fns);
1703 if (!is_overloaded_fn (fns))
1705 error ("%qD is not a function template", fns);
1706 return error_mark_node;
1709 /* Count the number of template headers specified for this
1712 for (b = current_binding_level;
1713 b->kind == sk_template_parms;
1717 for (; fns; fns = OVL_NEXT (fns))
1719 tree fn = OVL_CURRENT (fns);
1721 if (TREE_CODE (fn) == TEMPLATE_DECL)
1723 tree decl_arg_types;
1726 /* In case of explicit specialization, we need to check if
1727 the number of template headers appearing in the specialization
1728 is correct. This is usually done in check_explicit_specialization,
1729 but the check done there cannot be exhaustive when specializing
1730 member functions. Consider the following code:
1732 template <> void A<int>::f(int);
1733 template <> template <> void A<int>::f(int);
1735 Assuming that A<int> is not itself an explicit specialization
1736 already, the first line specializes "f" which is a non-template
1737 member function, whilst the second line specializes "f" which
1738 is a template member function. So both lines are syntactically
1739 correct, and check_explicit_specialization does not reject
1742 Here, we can do better, as we are matching the specialization
1743 against the declarations. We count the number of template
1744 headers, and we check if they match TEMPLATE_COUNT + 1
1745 (TEMPLATE_COUNT is the number of qualifying template classes,
1746 plus there must be another header for the member template
1749 Notice that if header_count is zero, this is not a
1750 specialization but rather a template instantiation, so there
1751 is no check we can perform here. */
1752 if (header_count && header_count != template_count + 1)
1755 /* Check that the number of template arguments at the
1756 innermost level for DECL is the same as for FN. */
1757 if (current_binding_level->kind == sk_template_parms
1758 && !current_binding_level->explicit_spec_p
1759 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1760 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS
1761 (current_template_parms))))
1764 /* DECL might be a specialization of FN. */
1765 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1766 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1768 /* For a non-static member function, we need to make sure
1769 that the const qualification is the same. Since
1770 get_bindings does not try to merge the "this" parameter,
1771 we must do the comparison explicitly. */
1772 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1773 && !same_type_p (TREE_VALUE (fn_arg_types),
1774 TREE_VALUE (decl_arg_types)))
1777 /* Skip the "this" parameter and, for constructors of
1778 classes with virtual bases, the VTT parameter. A
1779 full specialization of a constructor will have a VTT
1780 parameter, but a template never will. */
1782 = skip_artificial_parms_for (decl, decl_arg_types);
1784 = skip_artificial_parms_for (fn, fn_arg_types);
1786 /* Check that the number of function parameters matches.
1788 template <class T> void f(int i = 0);
1789 template <> void f<int>();
1790 The specialization f<int> is invalid but is not caught
1791 by get_bindings below. */
1792 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1795 /* Function templates cannot be specializations; there are
1796 no partial specializations of functions. Therefore, if
1797 the type of DECL does not match FN, there is no
1799 if (tsk == tsk_template)
1801 if (compparms (fn_arg_types, decl_arg_types))
1802 candidates = tree_cons (NULL_TREE, fn, candidates);
1806 /* See whether this function might be a specialization of this
1808 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1811 /* We cannot deduce template arguments that when used to
1812 specialize TMPL will produce DECL. */
1815 /* Save this template, and the arguments deduced. */
1816 templates = tree_cons (targs, fn, templates);
1818 else if (need_member_template)
1819 /* FN is an ordinary member function, and we need a
1820 specialization of a member template. */
1822 else if (TREE_CODE (fn) != FUNCTION_DECL)
1823 /* We can get IDENTIFIER_NODEs here in certain erroneous
1826 else if (!DECL_FUNCTION_MEMBER_P (fn))
1827 /* This is just an ordinary non-member function. Nothing can
1828 be a specialization of that. */
1830 else if (DECL_ARTIFICIAL (fn))
1831 /* Cannot specialize functions that are created implicitly. */
1835 tree decl_arg_types;
1837 /* This is an ordinary member function. However, since
1838 we're here, we can assume it's enclosing class is a
1839 template class. For example,
1841 template <typename T> struct S { void f(); };
1842 template <> void S<int>::f() {}
1844 Here, S<int>::f is a non-template, but S<int> is a
1845 template class. If FN has the same type as DECL, we
1846 might be in business. */
1848 if (!DECL_TEMPLATE_INFO (fn))
1849 /* Its enclosing class is an explicit specialization
1850 of a template class. This is not a candidate. */
1853 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1854 TREE_TYPE (TREE_TYPE (fn))))
1855 /* The return types differ. */
1858 /* Adjust the type of DECL in case FN is a static member. */
1859 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1860 if (DECL_STATIC_FUNCTION_P (fn)
1861 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1862 decl_arg_types = TREE_CHAIN (decl_arg_types);
1864 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1867 candidates = tree_cons (NULL_TREE, fn, candidates);
1871 if (templates && TREE_CHAIN (templates))
1877 It is possible for a specialization with a given function
1878 signature to be instantiated from more than one function
1879 template. In such cases, explicit specification of the
1880 template arguments must be used to uniquely identify the
1881 function template specialization being specialized.
1883 Note that here, there's no suggestion that we're supposed to
1884 determine which of the candidate templates is most
1885 specialized. However, we, also have:
1889 Partial ordering of overloaded function template
1890 declarations is used in the following contexts to select
1891 the function template to which a function template
1892 specialization refers:
1894 -- when an explicit specialization refers to a function
1897 So, we do use the partial ordering rules, at least for now.
1898 This extension can only serve to make invalid programs valid,
1899 so it's safe. And, there is strong anecdotal evidence that
1900 the committee intended the partial ordering rules to apply;
1901 the EDG front end has that behavior, and John Spicer claims
1902 that the committee simply forgot to delete the wording in
1903 [temp.expl.spec]. */
1904 tree tmpl = most_specialized_instantiation (templates);
1905 if (tmpl != error_mark_node)
1908 TREE_CHAIN (templates) = NULL_TREE;
1912 if (templates == NULL_TREE && candidates == NULL_TREE)
1914 error ("template-id %qD for %q+D does not match any template "
1915 "declaration", template_id, decl);
1916 return error_mark_node;
1918 else if ((templates && TREE_CHAIN (templates))
1919 || (candidates && TREE_CHAIN (candidates))
1920 || (templates && candidates))
1922 error ("ambiguous template specialization %qD for %q+D",
1924 chainon (candidates, templates);
1925 print_candidates (candidates);
1926 return error_mark_node;
1929 /* We have one, and exactly one, match. */
1932 tree fn = TREE_VALUE (candidates);
1933 *targs_out = copy_node (DECL_TI_ARGS (fn));
1934 /* DECL is a re-declaration or partial instantiation of a template
1936 if (TREE_CODE (fn) == TEMPLATE_DECL)
1938 /* It was a specialization of an ordinary member function in a
1940 return DECL_TI_TEMPLATE (fn);
1943 /* It was a specialization of a template. */
1944 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1945 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1947 *targs_out = copy_node (targs);
1948 SET_TMPL_ARGS_LEVEL (*targs_out,
1949 TMPL_ARGS_DEPTH (*targs_out),
1950 TREE_PURPOSE (templates));
1953 *targs_out = TREE_PURPOSE (templates);
1954 return TREE_VALUE (templates);
1957 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1958 but with the default argument values filled in from those in the
1962 copy_default_args_to_explicit_spec_1 (tree spec_types,
1965 tree new_spec_types;
1970 if (spec_types == void_list_node)
1971 return void_list_node;
1973 /* Substitute into the rest of the list. */
1975 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1976 TREE_CHAIN (tmpl_types));
1978 /* Add the default argument for this parameter. */
1979 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1980 TREE_VALUE (spec_types),
1984 /* DECL is an explicit specialization. Replicate default arguments
1985 from the template it specializes. (That way, code like:
1987 template <class T> void f(T = 3);
1988 template <> void f(double);
1991 works, as required.) An alternative approach would be to look up
1992 the correct default arguments at the call-site, but this approach
1993 is consistent with how implicit instantiations are handled. */
1996 copy_default_args_to_explicit_spec (tree decl)
2001 tree new_spec_types;
2005 tree object_type = NULL_TREE;
2006 tree in_charge = NULL_TREE;
2007 tree vtt = NULL_TREE;
2009 /* See if there's anything we need to do. */
2010 tmpl = DECL_TI_TEMPLATE (decl);
2011 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
2012 for (t = tmpl_types; t; t = TREE_CHAIN (t))
2013 if (TREE_PURPOSE (t))
2018 old_type = TREE_TYPE (decl);
2019 spec_types = TYPE_ARG_TYPES (old_type);
2021 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2023 /* Remove the this pointer, but remember the object's type for
2025 object_type = TREE_TYPE (TREE_VALUE (spec_types));
2026 spec_types = TREE_CHAIN (spec_types);
2027 tmpl_types = TREE_CHAIN (tmpl_types);
2029 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
2031 /* DECL may contain more parameters than TMPL due to the extra
2032 in-charge parameter in constructors and destructors. */
2033 in_charge = spec_types;
2034 spec_types = TREE_CHAIN (spec_types);
2036 if (DECL_HAS_VTT_PARM_P (decl))
2039 spec_types = TREE_CHAIN (spec_types);
2043 /* Compute the merged default arguments. */
2045 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
2047 /* Compute the new FUNCTION_TYPE. */
2051 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
2056 /* Put the in-charge parameter back. */
2057 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
2058 TREE_VALUE (in_charge),
2061 new_type = build_method_type_directly (object_type,
2062 TREE_TYPE (old_type),
2066 new_type = build_function_type (TREE_TYPE (old_type),
2068 new_type = cp_build_type_attribute_variant (new_type,
2069 TYPE_ATTRIBUTES (old_type));
2070 new_type = build_exception_variant (new_type,
2071 TYPE_RAISES_EXCEPTIONS (old_type));
2072 TREE_TYPE (decl) = new_type;
2075 /* Check to see if the function just declared, as indicated in
2076 DECLARATOR, and in DECL, is a specialization of a function
2077 template. We may also discover that the declaration is an explicit
2078 instantiation at this point.
2080 Returns DECL, or an equivalent declaration that should be used
2081 instead if all goes well. Issues an error message if something is
2082 amiss. Returns error_mark_node if the error is not easily
2085 FLAGS is a bitmask consisting of the following flags:
2087 2: The function has a definition.
2088 4: The function is a friend.
2090 The TEMPLATE_COUNT is the number of references to qualifying
2091 template classes that appeared in the name of the function. For
2094 template <class T> struct S { void f(); };
2097 the TEMPLATE_COUNT would be 1. However, explicitly specialized
2098 classes are not counted in the TEMPLATE_COUNT, so that in
2100 template <class T> struct S {};
2101 template <> struct S<int> { void f(); }
2102 template <> void S<int>::f();
2104 the TEMPLATE_COUNT would be 0. (Note that this declaration is
2105 invalid; there should be no template <>.)
2107 If the function is a specialization, it is marked as such via
2108 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
2109 is set up correctly, and it is added to the list of specializations
2110 for that template. */
2113 check_explicit_specialization (tree declarator,
2118 int have_def = flags & 2;
2119 int is_friend = flags & 4;
2120 int specialization = 0;
2121 int explicit_instantiation = 0;
2122 int member_specialization = 0;
2123 tree ctype = DECL_CLASS_CONTEXT (decl);
2124 tree dname = DECL_NAME (decl);
2129 if (!processing_specialization)
2132 tsk = tsk_excessive_parms;
2135 tsk = current_tmpl_spec_kind (template_count);
2140 if (processing_specialization)
2143 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2145 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2148 /* This could be something like:
2150 template <class T> void f(T);
2151 class S { friend void f<>(int); } */
2155 /* This case handles bogus declarations like template <>
2156 template <class T> void f<int>(); */
2158 error ("template-id %qD in declaration of primary template",
2165 case tsk_invalid_member_spec:
2166 /* The error has already been reported in
2167 check_specialization_scope. */
2168 return error_mark_node;
2170 case tsk_invalid_expl_inst:
2171 error ("template parameter list used in explicit instantiation");
2177 error ("definition provided for explicit instantiation");
2179 explicit_instantiation = 1;
2182 case tsk_excessive_parms:
2183 case tsk_insufficient_parms:
2184 if (tsk == tsk_excessive_parms)
2185 error ("too many template parameter lists in declaration of %qD",
2187 else if (template_header_count)
2188 error("too few template parameter lists in declaration of %qD", decl);
2190 error("explicit specialization of %qD must be introduced by "
2191 "%<template <>%>", decl);
2195 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
2197 member_specialization = 1;
2203 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
2205 /* This case handles bogus declarations like template <>
2206 template <class T> void f<int>(); */
2208 if (uses_template_parms (declarator))
2209 error ("function template partial specialization %qD "
2210 "is not allowed", declarator);
2212 error ("template-id %qD in declaration of primary template",
2217 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
2218 /* This is a specialization of a member template, without
2219 specialization the containing class. Something like:
2221 template <class T> struct S {
2222 template <class U> void f (U);
2224 template <> template <class U> void S<int>::f(U) {}
2226 That's a specialization -- but of the entire template. */
2234 if (specialization || member_specialization)
2236 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
2237 for (; t; t = TREE_CHAIN (t))
2238 if (TREE_PURPOSE (t))
2240 permerror (input_location,
2241 "default argument specified in explicit specialization");
2246 if (specialization || member_specialization || explicit_instantiation)
2248 tree tmpl = NULL_TREE;
2249 tree targs = NULL_TREE;
2251 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
2252 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
2256 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
2261 /* If there is no class context, the explicit instantiation
2262 must be at namespace scope. */
2263 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
2265 /* Find the namespace binding, using the declaration
2267 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname,
2269 if (fns == error_mark_node || !is_overloaded_fn (fns))
2271 error ("%qD is not a template function", dname);
2272 fns = error_mark_node;
2276 tree fn = OVL_CURRENT (fns);
2277 if (!is_associated_namespace (CP_DECL_CONTEXT (decl),
2278 CP_DECL_CONTEXT (fn)))
2279 error ("%qD is not declared in %qD",
2280 decl, current_namespace);
2284 declarator = lookup_template_function (fns, NULL_TREE);
2287 if (declarator == error_mark_node)
2288 return error_mark_node;
2290 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
2292 if (!explicit_instantiation)
2293 /* A specialization in class scope. This is invalid,
2294 but the error will already have been flagged by
2295 check_specialization_scope. */
2296 return error_mark_node;
2299 /* It's not valid to write an explicit instantiation in
2302 class C { template void f(); }
2304 This case is caught by the parser. However, on
2307 template class C { void f(); };
2309 (which is invalid) we can get here. The error will be
2316 else if (ctype != NULL_TREE
2317 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
2320 /* Find the list of functions in ctype that have the same
2321 name as the declared function. */
2322 tree name = TREE_OPERAND (declarator, 0);
2323 tree fns = NULL_TREE;
2326 if (constructor_name_p (name, ctype))
2328 int is_constructor = DECL_CONSTRUCTOR_P (decl);
2330 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype)
2331 : !CLASSTYPE_DESTRUCTORS (ctype))
2333 /* From [temp.expl.spec]:
2335 If such an explicit specialization for the member
2336 of a class template names an implicitly-declared
2337 special member function (clause _special_), the
2338 program is ill-formed.
2340 Similar language is found in [temp.explicit]. */
2341 error ("specialization of implicitly-declared special member function");
2342 return error_mark_node;
2345 name = is_constructor ? ctor_identifier : dtor_identifier;
2348 if (!DECL_CONV_FN_P (decl))
2350 idx = lookup_fnfields_1 (ctype, name);
2352 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
2356 VEC(tree,gc) *methods;
2359 /* For a type-conversion operator, we cannot do a
2360 name-based lookup. We might be looking for `operator
2361 int' which will be a specialization of `operator T'.
2362 So, we find *all* the conversion operators, and then
2363 select from them. */
2366 methods = CLASSTYPE_METHOD_VEC (ctype);
2368 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
2369 VEC_iterate (tree, methods, idx, ovl);
2372 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2373 /* There are no more conversion functions. */
2376 /* Glue all these conversion functions together
2377 with those we already have. */
2378 for (; ovl; ovl = OVL_NEXT (ovl))
2379 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2383 if (fns == NULL_TREE)
2385 error ("no member function %qD declared in %qT", name, ctype);
2386 return error_mark_node;
2389 TREE_OPERAND (declarator, 0) = fns;
2392 /* Figure out what exactly is being specialized at this point.
2393 Note that for an explicit instantiation, even one for a
2394 member function, we cannot tell apriori whether the
2395 instantiation is for a member template, or just a member
2396 function of a template class. Even if a member template is
2397 being instantiated, the member template arguments may be
2398 elided if they can be deduced from the rest of the
2400 tmpl = determine_specialization (declarator, decl,
2402 member_specialization,
2406 if (!tmpl || tmpl == error_mark_node)
2407 /* We couldn't figure out what this declaration was
2409 return error_mark_node;
2412 tree gen_tmpl = most_general_template (tmpl);
2414 if (explicit_instantiation)
2416 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2417 is done by do_decl_instantiation later. */
2419 int arg_depth = TMPL_ARGS_DEPTH (targs);
2420 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2422 if (arg_depth > parm_depth)
2424 /* If TMPL is not the most general template (for
2425 example, if TMPL is a friend template that is
2426 injected into namespace scope), then there will
2427 be too many levels of TARGS. Remove some of them
2432 new_targs = make_tree_vec (parm_depth);
2433 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2434 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2435 = TREE_VEC_ELT (targs, i);
2439 return instantiate_template (tmpl, targs, tf_error);
2442 /* If we thought that the DECL was a member function, but it
2443 turns out to be specializing a static member function,
2444 make DECL a static member function as well. */
2445 if (DECL_STATIC_FUNCTION_P (tmpl)
2446 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2447 revert_static_member_fn (decl);
2449 /* If this is a specialization of a member template of a
2450 template class, we want to return the TEMPLATE_DECL, not
2451 the specialization of it. */
2452 if (tsk == tsk_template)
2454 tree result = DECL_TEMPLATE_RESULT (tmpl);
2455 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2456 DECL_INITIAL (result) = NULL_TREE;
2460 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2461 DECL_SOURCE_LOCATION (result)
2462 = DECL_SOURCE_LOCATION (decl);
2463 /* We want to use the argument list specified in the
2464 definition, not in the original declaration. */
2465 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl);
2466 for (parm = DECL_ARGUMENTS (result); parm;
2467 parm = TREE_CHAIN (parm))
2468 DECL_CONTEXT (parm) = result;
2470 return register_specialization (tmpl, gen_tmpl, targs,
2474 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2475 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2477 /* Inherit default function arguments from the template
2478 DECL is specializing. */
2479 copy_default_args_to_explicit_spec (decl);
2481 /* This specialization has the same protection as the
2482 template it specializes. */
2483 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2484 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2486 /* 7.1.1-1 [dcl.stc]
2488 A storage-class-specifier shall not be specified in an
2489 explicit specialization...
2491 The parser rejects these, so unless action is taken here,
2492 explicit function specializations will always appear with
2495 The action recommended by the C++ CWG in response to C++
2496 defect report 605 is to make the storage class and linkage
2497 of the explicit specialization match the templated function:
2499 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605
2501 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl))
2503 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl);
2504 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL);
2506 /* This specialization has the same linkage and visibility as
2507 the function template it specializes. */
2508 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func);
2509 if (! TREE_PUBLIC (decl))
2511 DECL_INTERFACE_KNOWN (decl) = 1;
2512 DECL_NOT_REALLY_EXTERN (decl) = 1;
2514 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func);
2515 if (DECL_VISIBILITY_SPECIFIED (tmpl_func))
2517 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2518 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func);
2522 /* If DECL is a friend declaration, declared using an
2523 unqualified name, the namespace associated with DECL may
2524 have been set incorrectly. For example, in:
2526 template <typename T> void f(T);
2528 struct S { friend void f<int>(int); }
2531 we will have set the DECL_CONTEXT for the friend
2532 declaration to N, rather than to the global namespace. */
2533 if (DECL_NAMESPACE_SCOPE_P (decl))
2534 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2536 if (is_friend && !have_def)
2537 /* This is not really a declaration of a specialization.
2538 It's just the name of an instantiation. But, it's not
2539 a request for an instantiation, either. */
2540 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2541 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2542 /* This is indeed a specialization. In case of constructors
2543 and destructors, we need in-charge and not-in-charge
2544 versions in V3 ABI. */
2545 clone_function_decl (decl, /*update_method_vec_p=*/0);
2547 /* Register this specialization so that we can find it
2549 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0);
2556 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2557 parameters. These are represented in the same format used for
2558 DECL_TEMPLATE_PARMS. */
2561 comp_template_parms (const_tree parms1, const_tree parms2)
2566 if (parms1 == parms2)
2569 for (p1 = parms1, p2 = parms2;
2570 p1 != NULL_TREE && p2 != NULL_TREE;
2571 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2573 tree t1 = TREE_VALUE (p1);
2574 tree t2 = TREE_VALUE (p2);
2577 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2578 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2580 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2583 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2585 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2586 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2588 /* If either of the template parameters are invalid, assume
2589 they match for the sake of error recovery. */
2590 if (parm1 == error_mark_node || parm2 == error_mark_node)
2593 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2596 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM
2597 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1)
2598 == TEMPLATE_TYPE_PARAMETER_PACK (parm2)))
2600 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2605 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2606 /* One set of parameters has more parameters lists than the
2613 /* Determine whether PARM is a parameter pack. */
2615 template_parameter_pack_p (const_tree parm)
2617 /* Determine if we have a non-type template parameter pack. */
2618 if (TREE_CODE (parm) == PARM_DECL)
2619 return (DECL_TEMPLATE_PARM_P (parm)
2620 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)));
2622 /* If this is a list of template parameters, we could get a
2623 TYPE_DECL or a TEMPLATE_DECL. */
2624 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL)
2625 parm = TREE_TYPE (parm);
2627 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
2628 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM)
2629 && TEMPLATE_TYPE_PARAMETER_PACK (parm));
2632 /* Determine whether ARGS describes a variadic template args list,
2633 i.e., one that is terminated by a template argument pack. */
2635 template_args_variadic_p (tree args)
2640 if (args == NULL_TREE)
2643 args = INNERMOST_TEMPLATE_ARGS (args);
2644 nargs = TREE_VEC_LENGTH (args);
2649 last_parm = TREE_VEC_ELT (args, nargs - 1);
2651 return ARGUMENT_PACK_P (last_parm);
2654 /* Generate a new name for the parameter pack name NAME (an
2655 IDENTIFIER_NODE) that incorporates its */
2657 make_ith_pack_parameter_name (tree name, int i)
2659 /* Munge the name to include the parameter index. */
2663 sprintf(numbuf, "%i", i);
2664 newname = (char*)alloca (IDENTIFIER_LENGTH (name) + strlen(numbuf) + 2);
2665 sprintf(newname, "%s#%i", IDENTIFIER_POINTER (name), i);
2666 return get_identifier (newname);
2669 /* Structure used to track the progress of find_parameter_packs_r. */
2670 struct find_parameter_pack_data
2672 /* TREE_LIST that will contain all of the parameter packs found by
2674 tree* parameter_packs;
2676 /* Set of AST nodes that have been visited by the traversal. */
2677 struct pointer_set_t *visited;
2680 /* Identifies all of the argument packs that occur in a template
2681 argument and appends them to the TREE_LIST inside DATA, which is a
2682 find_parameter_pack_data structure. This is a subroutine of
2683 make_pack_expansion and uses_parameter_packs. */
2685 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data)
2688 struct find_parameter_pack_data* ppd =
2689 (struct find_parameter_pack_data*)data;
2690 bool parameter_pack_p = false;
2692 /* Identify whether this is a parameter pack or not. */
2693 switch (TREE_CODE (t))
2695 case TEMPLATE_PARM_INDEX:
2696 if (TEMPLATE_PARM_PARAMETER_PACK (t))
2697 parameter_pack_p = true;
2700 case TEMPLATE_TYPE_PARM:
2701 case TEMPLATE_TEMPLATE_PARM:
2702 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
2703 parameter_pack_p = true;
2707 if (FUNCTION_PARAMETER_PACK_P (t))
2709 /* We don't want to walk into the type of a PARM_DECL,
2710 because we don't want to see the type parameter pack. */
2712 parameter_pack_p = true;
2717 /* Not a parameter pack. */
2721 if (parameter_pack_p)
2723 /* Add this parameter pack to the list. */
2724 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs);
2728 cp_walk_tree (&TYPE_CONTEXT (t),
2729 &find_parameter_packs_r, ppd, ppd->visited);
2731 /* This switch statement will return immediately if we don't find a
2733 switch (TREE_CODE (t))
2735 case TEMPLATE_PARM_INDEX:
2738 case BOUND_TEMPLATE_TEMPLATE_PARM:
2739 /* Check the template itself. */
2740 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)),
2741 &find_parameter_packs_r, ppd, ppd->visited);
2742 /* Check the template arguments. */
2743 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd,
2748 case TEMPLATE_TYPE_PARM:
2749 case TEMPLATE_TEMPLATE_PARM:
2756 if (TYPE_PTRMEMFUNC_P (t))
2762 if (TYPE_TEMPLATE_INFO (t))
2763 cp_walk_tree (&TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
2764 &find_parameter_packs_r, ppd, ppd->visited);
2770 cp_walk_tree (&TREE_TYPE (t),
2771 &find_parameter_packs_r, ppd, ppd->visited);
2775 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r,
2780 case TYPE_PACK_EXPANSION:
2781 case EXPR_PACK_EXPANSION:
2786 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r,
2791 case IDENTIFIER_NODE:
2792 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd,
2804 /* Determines if the expression or type T uses any parameter packs. */
2806 uses_parameter_packs (tree t)
2808 tree parameter_packs = NULL_TREE;
2809 struct find_parameter_pack_data ppd;
2810 ppd.parameter_packs = ¶meter_packs;
2811 ppd.visited = pointer_set_create ();
2812 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2813 pointer_set_destroy (ppd.visited);
2814 return parameter_packs != NULL_TREE;
2817 /* Turn ARG, which may be an expression, type, or a TREE_LIST
2818 representation a base-class initializer into a parameter pack
2819 expansion. If all goes well, the resulting node will be an
2820 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST,
2823 make_pack_expansion (tree arg)
2826 tree parameter_packs = NULL_TREE;
2827 bool for_types = false;
2828 struct find_parameter_pack_data ppd;
2830 if (!arg || arg == error_mark_node)
2833 if (TREE_CODE (arg) == TREE_LIST)
2835 /* The only time we will see a TREE_LIST here is for a base
2836 class initializer. In this case, the TREE_PURPOSE will be a
2837 _TYPE node (representing the base class expansion we're
2838 initializing) and the TREE_VALUE will be a TREE_LIST
2839 containing the initialization arguments.
2841 The resulting expansion looks somewhat different from most
2842 expansions. Rather than returning just one _EXPANSION, we
2843 return a TREE_LIST whose TREE_PURPOSE is a
2844 TYPE_PACK_EXPANSION containing the bases that will be
2845 initialized. The TREE_VALUE will be identical to the
2846 original TREE_VALUE, which is a list of arguments that will
2847 be passed to each base. We do not introduce any new pack
2848 expansion nodes into the TREE_VALUE (although it is possible
2849 that some already exist), because the TREE_PURPOSE and
2850 TREE_VALUE all need to be expanded together with the same
2851 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the
2852 resulting TREE_PURPOSE will mention the parameter packs in
2853 both the bases and the arguments to the bases. */
2856 tree parameter_packs = NULL_TREE;
2858 /* Determine which parameter packs will be used by the base
2860 ppd.visited = pointer_set_create ();
2861 ppd.parameter_packs = ¶meter_packs;
2862 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r,
2865 if (parameter_packs == NULL_TREE)
2867 error ("base initializer expansion %<%T%> contains no parameter packs", arg);
2868 pointer_set_destroy (ppd.visited);
2869 return error_mark_node;
2872 if (TREE_VALUE (arg) != void_type_node)
2874 /* Collect the sets of parameter packs used in each of the
2875 initialization arguments. */
2876 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value))
2878 /* Determine which parameter packs will be expanded in this
2880 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r,
2885 pointer_set_destroy (ppd.visited);
2887 /* Create the pack expansion type for the base type. */
2888 purpose = make_node (TYPE_PACK_EXPANSION);
2889 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg));
2890 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs;
2892 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2893 they will rarely be compared to anything. */
2894 SET_TYPE_STRUCTURAL_EQUALITY (purpose);
2896 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE);
2899 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)
2902 /* Build the PACK_EXPANSION_* node. */
2903 result = make_node (for_types ? TYPE_PACK_EXPANSION : EXPR_PACK_EXPANSION);
2904 SET_PACK_EXPANSION_PATTERN (result, arg);
2905 if (TREE_CODE (result) == EXPR_PACK_EXPANSION)
2907 /* Propagate type and const-expression information. */
2908 TREE_TYPE (result) = TREE_TYPE (arg);
2909 TREE_CONSTANT (result) = TREE_CONSTANT (arg);
2912 /* Just use structural equality for these TYPE_PACK_EXPANSIONS;
2913 they will rarely be compared to anything. */
2914 SET_TYPE_STRUCTURAL_EQUALITY (result);
2916 /* Determine which parameter packs will be expanded. */
2917 ppd.parameter_packs = ¶meter_packs;
2918 ppd.visited = pointer_set_create ();
2919 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited);
2920 pointer_set_destroy (ppd.visited);
2922 /* Make sure we found some parameter packs. */
2923 if (parameter_packs == NULL_TREE)
2926 error ("expansion pattern %<%T%> contains no argument packs", arg);
2928 error ("expansion pattern %<%E%> contains no argument packs", arg);
2929 return error_mark_node;
2931 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs;
2936 /* Checks T for any "bare" parameter packs, which have not yet been
2937 expanded, and issues an error if any are found. This operation can
2938 only be done on full expressions or types (e.g., an expression
2939 statement, "if" condition, etc.), because we could have expressions like:
2941 foo(f(g(h(args)))...)
2943 where "args" is a parameter pack. check_for_bare_parameter_packs
2944 should not be called for the subexpressions args, h(args),
2945 g(h(args)), or f(g(h(args))), because we would produce erroneous
2948 Returns TRUE and emits an error if there were bare parameter packs,
2949 returns FALSE otherwise. */
2951 check_for_bare_parameter_packs (tree t)
2953 tree parameter_packs = NULL_TREE;
2954 struct find_parameter_pack_data ppd;
2956 if (!processing_template_decl || !t || t == error_mark_node)
2959 if (TREE_CODE (t) == TYPE_DECL)
2962 ppd.parameter_packs = ¶meter_packs;
2963 ppd.visited = pointer_set_create ();
2964 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited);
2965 pointer_set_destroy (ppd.visited);
2967 if (parameter_packs)
2969 error ("parameter packs not expanded with %<...%>:");
2970 while (parameter_packs)
2972 tree pack = TREE_VALUE (parameter_packs);
2973 tree name = NULL_TREE;
2975 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM
2976 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM)
2977 name = TYPE_NAME (pack);
2978 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX)
2979 name = DECL_NAME (TEMPLATE_PARM_DECL (pack));
2981 name = DECL_NAME (pack);
2984 inform (input_location, " %qD", name);
2986 inform (input_location, " <anonymous>");
2988 parameter_packs = TREE_CHAIN (parameter_packs);
2997 /* Expand any parameter packs that occur in the template arguments in
3000 expand_template_argument_pack (tree args)
3002 tree result_args = NULL_TREE;
3003 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0;
3004 int num_result_args = -1;
3006 /* First, determine if we need to expand anything, and the number of
3007 slots we'll need. */
3008 for (in_arg = 0; in_arg < nargs; ++in_arg)
3010 tree arg = TREE_VEC_ELT (args, in_arg);
3011 if (ARGUMENT_PACK_P (arg))
3013 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg));
3014 if (num_result_args < 0)
3015 num_result_args = in_arg + num_packed;
3017 num_result_args += num_packed;
3021 if (num_result_args >= 0)
3026 /* If no expansion is necessary, we're done. */
3027 if (num_result_args < 0)
3030 /* Expand arguments. */
3031 result_args = make_tree_vec (num_result_args);
3032 for (in_arg = 0; in_arg < nargs; ++in_arg)
3034 tree arg = TREE_VEC_ELT (args, in_arg);
3035 if (ARGUMENT_PACK_P (arg))
3037 tree packed = ARGUMENT_PACK_ARGS (arg);
3038 int i, num_packed = TREE_VEC_LENGTH (packed);
3039 for (i = 0; i < num_packed; ++i, ++out_arg)
3040 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i);
3044 TREE_VEC_ELT (result_args, out_arg) = arg;
3052 /* Checks if DECL shadows a template parameter.
3054 [temp.local]: A template-parameter shall not be redeclared within its
3055 scope (including nested scopes).
3057 Emits an error and returns TRUE if the DECL shadows a parameter,
3058 returns FALSE otherwise. */
3061 check_template_shadow (tree decl)
3065 /* If we're not in a template, we can't possibly shadow a template
3067 if (!current_template_parms)
3070 /* Figure out what we're shadowing. */
3071 if (TREE_CODE (decl) == OVERLOAD)
3072 decl = OVL_CURRENT (decl);
3073 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
3075 /* If there's no previous binding for this name, we're not shadowing
3076 anything, let alone a template parameter. */
3080 /* If we're not shadowing a template parameter, we're done. Note
3081 that OLDDECL might be an OVERLOAD (or perhaps even an
3082 ERROR_MARK), so we can't just blithely assume it to be a _DECL
3084 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
3087 /* We check for decl != olddecl to avoid bogus errors for using a
3088 name inside a class. We check TPFI to avoid duplicate errors for
3089 inline member templates. */
3091 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
3094 error ("declaration of %q+#D", decl);
3095 error (" shadows template parm %q+#D", olddecl);
3099 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
3100 ORIG_LEVEL, DECL, and TYPE. */
3103 build_template_parm_index (int index,
3109 tree t = make_node (TEMPLATE_PARM_INDEX);
3110 TEMPLATE_PARM_IDX (t) = index;
3111 TEMPLATE_PARM_LEVEL (t) = level;
3112 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
3113 TEMPLATE_PARM_DECL (t) = decl;
3114 TREE_TYPE (t) = type;
3115 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
3116 TREE_READONLY (t) = TREE_READONLY (decl);
3121 /* Find the canonical type parameter for the given template type
3122 parameter. Returns the canonical type parameter, which may be TYPE
3123 if no such parameter existed. */
3125 canonical_type_parameter (tree type)
3128 int idx = TEMPLATE_TYPE_IDX (type);
3129 if (!canonical_template_parms)
3130 canonical_template_parms = VEC_alloc (tree, gc, idx+1);
3132 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx)
3133 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE);
3135 list = VEC_index (tree, canonical_template_parms, idx);
3136 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL))
3137 list = TREE_CHAIN (list);
3140 return TREE_VALUE (list);
3143 VEC_replace(tree, canonical_template_parms, idx,
3144 tree_cons (NULL_TREE, type,
3145 VEC_index (tree, canonical_template_parms, idx)));
3150 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
3151 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
3152 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
3153 new one is created. */
3156 reduce_template_parm_level (tree index, tree type, int levels, tree args,
3157 tsubst_flags_t complain)
3159 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
3160 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
3161 != TEMPLATE_PARM_LEVEL (index) - levels))
3163 tree orig_decl = TEMPLATE_PARM_DECL (index);
3166 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl),
3167 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
3168 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
3169 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
3170 DECL_ARTIFICIAL (decl) = 1;
3171 SET_DECL_TEMPLATE_PARM_P (decl);
3173 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
3174 TEMPLATE_PARM_LEVEL (index) - levels,
3175 TEMPLATE_PARM_ORIG_LEVEL (index),
3177 TEMPLATE_PARM_DESCENDANTS (index) = t;
3178 TEMPLATE_PARM_PARAMETER_PACK (t)
3179 = TEMPLATE_PARM_PARAMETER_PACK (index);
3181 /* Template template parameters need this. */
3182 if (TREE_CODE (decl) == TEMPLATE_DECL)
3183 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms
3184 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)),
3188 return TEMPLATE_PARM_DESCENDANTS (index);
3191 /* Process information from new template parameter PARM and append it to the
3192 LIST being built. This new parameter is a non-type parameter iff
3193 IS_NON_TYPE is true. This new parameter is a parameter
3194 pack iff IS_PARAMETER_PACK is true. The location of PARM is in
3198 process_template_parm (tree list, location_t parm_loc, tree parm, bool is_non_type,
3199 bool is_parameter_pack)
3206 gcc_assert (TREE_CODE (parm) == TREE_LIST);
3207 defval = TREE_PURPOSE (parm);
3211 tree p = tree_last (list);
3213 if (p && TREE_VALUE (p) != error_mark_node)
3216 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
3217 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
3219 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
3229 parm = TREE_VALUE (parm);
3231 SET_DECL_TEMPLATE_PARM_P (parm);
3233 if (TREE_TYPE (parm) == error_mark_node)
3235 err_parm_list = build_tree_list (defval, parm);
3236 TREE_VALUE (err_parm_list) = error_mark_node;
3237 return chainon (list, err_parm_list);
3243 The top-level cv-qualifiers on the template-parameter are
3244 ignored when determining its type. */
3245 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
3246 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
3248 err_parm_list = build_tree_list (defval, parm);
3249 TREE_VALUE (err_parm_list) = error_mark_node;
3250 return chainon (list, err_parm_list);
3253 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack)
3255 /* This template parameter is not a parameter pack, but it
3256 should be. Complain about "bare" parameter packs. */
3257 check_for_bare_parameter_packs (TREE_TYPE (parm));
3259 /* Recover by calling this a parameter pack. */
3260 is_parameter_pack = true;
3264 /* A template parameter is not modifiable. */
3265 TREE_CONSTANT (parm) = 1;
3266 TREE_READONLY (parm) = 1;
3267 decl = build_decl (parm_loc,
3268 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
3269 TREE_CONSTANT (decl) = 1;
3270 TREE_READONLY (decl) = 1;
3271 DECL_INITIAL (parm) = DECL_INITIAL (decl)
3272 = build_template_parm_index (idx, processing_template_decl,
3273 processing_template_decl,
3274 decl, TREE_TYPE (parm));
3276 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))
3277 = is_parameter_pack;
3282 parm = TREE_VALUE (TREE_VALUE (parm));
3284 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
3286 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM);
3287 /* This is for distinguishing between real templates and template
3288 template parameters */
3289 TREE_TYPE (parm) = t;
3290 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
3295 t = cxx_make_type (TEMPLATE_TYPE_PARM);
3296 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
3297 decl = build_decl (parm_loc,
3298 TYPE_DECL, parm, t);
3301 TYPE_NAME (t) = decl;
3302 TYPE_STUB_DECL (t) = decl;
3304 TEMPLATE_TYPE_PARM_INDEX (t)
3305 = build_template_parm_index (idx, processing_template_decl,
3306 processing_template_decl,
3307 decl, TREE_TYPE (parm));
3308 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack;
3309 TYPE_CANONICAL (t) = canonical_type_parameter (t);
3311 DECL_ARTIFICIAL (decl) = 1;
3312 SET_DECL_TEMPLATE_PARM_P (decl);
3314 parm = build_tree_list (defval, parm);
3315 return chainon (list, parm);
3318 /* The end of a template parameter list has been reached. Process the
3319 tree list into a parameter vector, converting each parameter into a more
3320 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
3324 end_template_parm_list (tree parms)
3328 tree saved_parmlist = make_tree_vec (list_length (parms));
3330 current_template_parms
3331 = tree_cons (size_int (processing_template_decl),
3332 saved_parmlist, current_template_parms);
3334 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
3336 next = TREE_CHAIN (parm);
3337 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
3338 TREE_CHAIN (parm) = NULL_TREE;
3341 --processing_template_parmlist;
3343 return saved_parmlist;
3346 /* end_template_decl is called after a template declaration is seen. */
3349 end_template_decl (void)
3351 reset_specialization ();
3353 if (! processing_template_decl)
3356 /* This matches the pushlevel in begin_template_parm_list. */
3359 --processing_template_decl;
3360 current_template_parms = TREE_CHAIN (current_template_parms);
3363 /* Within the declaration of a template, return all levels of template
3364 parameters that apply. The template parameters are represented as
3365 a TREE_VEC, in the form documented in cp-tree.h for template
3369 current_template_args (void)
3372 tree args = NULL_TREE;
3373 int length = TMPL_PARMS_DEPTH (current_template_parms);
3376 /* If there is only one level of template parameters, we do not
3377 create a TREE_VEC of TREE_VECs. Instead, we return a single
3378 TREE_VEC containing the arguments. */
3380 args = make_tree_vec (length);
3382 for (header = current_template_parms; header; header = TREE_CHAIN (header))
3384 tree a = copy_node (TREE_VALUE (header));
3387 TREE_TYPE (a) = NULL_TREE;
3388 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
3390 tree t = TREE_VEC_ELT (a, i);
3392 /* T will be a list if we are called from within a
3393 begin/end_template_parm_list pair, but a vector directly
3394 if within a begin/end_member_template_processing pair. */
3395 if (TREE_CODE (t) == TREE_LIST)
3399 if (!error_operand_p (t))
3401 if (TREE_CODE (t) == TYPE_DECL
3402 || TREE_CODE (t) == TEMPLATE_DECL)
3406 if (TEMPLATE_TYPE_PARAMETER_PACK (t))
3408 /* Turn this argument into a TYPE_ARGUMENT_PACK
3409 with a single element, which expands T. */
3410 tree vec = make_tree_vec (1);
3411 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3413 t = make_node (TYPE_ARGUMENT_PACK);
3414 SET_ARGUMENT_PACK_ARGS (t, vec);
3419 t = DECL_INITIAL (t);
3421 if (TEMPLATE_PARM_PARAMETER_PACK (t))
3423 /* Turn this argument into a NONTYPE_ARGUMENT_PACK
3424 with a single element, which expands T. */
3425 tree vec = make_tree_vec (1);
3426 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t));
3427 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t);
3429 t = make_node (NONTYPE_ARGUMENT_PACK);
3430 SET_ARGUMENT_PACK_ARGS (t, vec);
3431 TREE_TYPE (t) = type;
3434 TREE_VEC_ELT (a, i) = t;
3440 TREE_VEC_ELT (args, --l) = a;
3448 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
3449 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
3450 a member template. Used by push_template_decl below. */
3453 build_template_decl (tree decl, tree parms, bool member_template_p)
3455 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
3456 DECL_TEMPLATE_PARMS (tmpl) = parms;
3457 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
3458 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
3463 struct template_parm_data
3465 /* The level of the template parameters we are currently
3469 /* The index of the specialization argument we are currently
3473 /* An array whose size is the number of template parameters. The
3474 elements are nonzero if the parameter has been used in any one
3475 of the arguments processed so far. */
3478 /* An array whose size is the number of template arguments. The
3479 elements are nonzero if the argument makes use of template
3480 parameters of this level. */
3481 int* arg_uses_template_parms;
3484 /* Subroutine of push_template_decl used to see if each template
3485 parameter in a partial specialization is used in the explicit
3486 argument list. If T is of the LEVEL given in DATA (which is
3487 treated as a template_parm_data*), then DATA->PARMS is marked
3491 mark_template_parm (tree t, void* data)
3495 struct template_parm_data* tpd = (struct template_parm_data*) data;
3497 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3499 level = TEMPLATE_PARM_LEVEL (t);
3500 idx = TEMPLATE_PARM_IDX (t);
3504 level = TEMPLATE_TYPE_LEVEL (t);
3505 idx = TEMPLATE_TYPE_IDX (t);
3508 if (level == tpd->level)
3510 tpd->parms[idx] = 1;
3511 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
3514 /* Return zero so that for_each_template_parm will continue the
3515 traversal of the tree; we want to mark *every* template parm. */
3519 /* Process the partial specialization DECL. */
3522 process_partial_specialization (tree decl)
3524 tree type = TREE_TYPE (decl);
3525 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
3526 tree specargs = CLASSTYPE_TI_ARGS (type);
3527 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
3528 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
3530 int nargs = TREE_VEC_LENGTH (inner_args);
3533 int did_error_intro = 0;
3534 struct template_parm_data tpd;
3535 struct template_parm_data tpd2;
3537 gcc_assert (current_template_parms);
3539 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
3540 ntparms = TREE_VEC_LENGTH (inner_parms);
3542 /* We check that each of the template parameters given in the
3543 partial specialization is used in the argument list to the
3544 specialization. For example:
3546 template <class T> struct S;
3547 template <class T> struct S<T*>;
3549 The second declaration is OK because `T*' uses the template
3550 parameter T, whereas
3552 template <class T> struct S<int>;
3554 is no good. Even trickier is:
3565 The S2<T> declaration is actually invalid; it is a
3566 full-specialization. Of course,
3569 struct S2<T (*)(U)>;
3571 or some such would have been OK. */
3572 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
3573 tpd.parms = (int *) alloca (sizeof (int) * ntparms);
3574 memset (tpd.parms, 0, sizeof (int) * ntparms);
3576 tpd.arg_uses_template_parms = (int *) alloca (sizeof (int) * nargs);
3577 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
3578 for (i = 0; i < nargs; ++i)
3580 tpd.current_arg = i;
3581 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
3582 &mark_template_parm,
3585 /*include_nondeduced_p=*/false);
3587 for (i = 0; i < ntparms; ++i)
3588 if (tpd.parms[i] == 0)
3590 /* One of the template parms was not used in the
3592 if (!did_error_intro)
3594 error ("template parameters not used in partial specialization:");
3595 did_error_intro = 1;
3598 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
3601 /* [temp.class.spec]
3603 The argument list of the specialization shall not be identical to
3604 the implicit argument list of the primary template. */
3605 if (comp_template_args
3607 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
3609 error ("partial specialization %qT does not specialize any template arguments", type);
3611 /* [temp.class.spec]
3613 A partially specialized non-type argument expression shall not
3614 involve template parameters of the partial specialization except
3615 when the argument expression is a simple identifier.
3617 The type of a template parameter corresponding to a specialized
3618 non-type argument shall not be dependent on a parameter of the
3621 Also, we verify that pack expansions only occur at the
3622 end of the argument list. */
3623 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
3625 for (i = 0; i < nargs; ++i)
3627 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i));
3628 tree arg = TREE_VEC_ELT (inner_args, i);
3629 tree packed_args = NULL_TREE;
3632 if (ARGUMENT_PACK_P (arg))
3634 /* Extract the arguments from the argument pack. We'll be
3635 iterating over these in the following loop. */
3636 packed_args = ARGUMENT_PACK_ARGS (arg);
3637 len = TREE_VEC_LENGTH (packed_args);
3640 for (j = 0; j < len; j++)
3643 /* Get the Jth argument in the parameter pack. */
3644 arg = TREE_VEC_ELT (packed_args, j);
3646 if (PACK_EXPANSION_P (arg))
3648 /* Pack expansions must come at the end of the
3650 if ((packed_args && j < len - 1)
3651 || (!packed_args && i < nargs - 1))
3653 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3654 error ("parameter pack argument %qE must be at the end of the template argument list", arg);
3656 error ("parameter pack argument %qT must be at the end of the template argument list", arg);
3659 TREE_VEC_ELT (packed_args, j) = error_mark_node;
3663 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
3664 /* We only care about the pattern. */
3665 arg = PACK_EXPANSION_PATTERN (arg);
3667 if (/* These first two lines are the `non-type' bit. */
3669 && TREE_CODE (arg) != TEMPLATE_DECL
3670 /* This next line is the `argument expression is not just a
3671 simple identifier' condition and also the `specialized
3672 non-type argument' bit. */
3673 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
3675 if ((!packed_args && tpd.arg_uses_template_parms[i])
3676 || (packed_args && uses_template_parms (arg)))
3677 error ("template argument %qE involves template parameter(s)",
3681 /* Look at the corresponding template parameter,
3682 marking which template parameters its type depends
3684 tree type = TREE_TYPE (parm);
3688 /* We haven't yet initialized TPD2. Do so now. */
3689 tpd2.arg_uses_template_parms
3690 = (int *) alloca (sizeof (int) * nargs);
3691 /* The number of parameters here is the number in the
3692 main template, which, as checked in the assertion
3694 tpd2.parms = (int *) alloca (sizeof (int) * nargs);
3696 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
3699 /* Mark the template parameters. But this time, we're
3700 looking for the template parameters of the main
3701 template, not in the specialization. */
3702 tpd2.current_arg = i;
3703 tpd2.arg_uses_template_parms[i] = 0;
3704 memset (tpd2.parms, 0, sizeof (int) * nargs);
3705 for_each_template_parm (type,
3706 &mark_template_parm,
3709 /*include_nondeduced_p=*/false);
3711 if (tpd2.arg_uses_template_parms [i])
3713 /* The type depended on some template parameters.
3714 If they are fully specialized in the
3715 specialization, that's OK. */
3717 for (j = 0; j < nargs; ++j)
3718 if (tpd2.parms[j] != 0
3719 && tpd.arg_uses_template_parms [j])
3721 error ("type %qT of template argument %qE depends "
3722 "on template parameter(s)",
3733 /* We should only get here once. */
3734 gcc_assert (!COMPLETE_TYPE_P (type));
3736 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
3737 = tree_cons (specargs, inner_parms,
3738 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
3739 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
3743 /* Check that a template declaration's use of default arguments and
3744 parameter packs is not invalid. Here, PARMS are the template
3745 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by
3746 a primary template. IS_PARTIAL is nonzero if DECL is a partial
3750 IS_FRIEND_DECL is nonzero if DECL is a friend function template
3751 declaration (but not a definition); 1 indicates a declaration, 2
3752 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are
3753 emitted for extraneous default arguments.
3755 Returns TRUE if there were no errors found, FALSE otherwise. */
3758 check_default_tmpl_args (tree decl, tree parms, int is_primary,
3759 int is_partial, int is_friend_decl)
3762 int last_level_to_check;
3764 bool no_errors = true;
3768 A default template-argument shall not be specified in a
3769 function template declaration or a function template definition, nor
3770 in the template-parameter-list of the definition of a member of a
3773 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
3774 /* You can't have a function template declaration in a local
3775 scope, nor you can you define a member of a class template in a
3779 if (current_class_type
3780 && !TYPE_BEING_DEFINED (current_class_type)
3781 && DECL_LANG_SPECIFIC (decl)
3782 && DECL_DECLARES_FUNCTION_P (decl)
3783 /* If this is either a friend defined in the scope of the class
3784 or a member function. */
3785 && (DECL_FUNCTION_MEMBER_P (decl)
3786 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
3787 : DECL_FRIEND_CONTEXT (decl)
3788 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
3790 /* And, if it was a member function, it really was defined in
3791 the scope of the class. */
3792 && (!DECL_FUNCTION_MEMBER_P (decl)
3793 || DECL_INITIALIZED_IN_CLASS_P (decl)))
3794 /* We already checked these parameters when the template was
3795 declared, so there's no need to do it again now. This function
3796 was defined in class scope, but we're processing it's body now
3797 that the class is complete. */
3800 /* Core issue 226 (C++0x only): the following only applies to class
3802 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL)
3806 If a template-parameter has a default template-argument, all
3807 subsequent template-parameters shall have a default
3808 template-argument supplied. */
3809 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
3811 tree inner_parms = TREE_VALUE (parm_level);
3812 int ntparms = TREE_VEC_LENGTH (inner_parms);
3813 int seen_def_arg_p = 0;
3816 for (i = 0; i < ntparms; ++i)
3818 tree parm = TREE_VEC_ELT (inner_parms, i);
3820 if (parm == error_mark_node)
3823 if (TREE_PURPOSE (parm))
3825 else if (seen_def_arg_p
3826 && !template_parameter_pack_p (TREE_VALUE (parm)))
3828 error ("no default argument for %qD", TREE_VALUE (parm));
3829 /* For better subsequent error-recovery, we indicate that
3830 there should have been a default argument. */
3831 TREE_PURPOSE (parm) = error_mark_node;
3837 /* Don't complain about an enclosing partial
3839 && parm_level == parms
3840 && TREE_CODE (decl) == TYPE_DECL
3842 && template_parameter_pack_p (TREE_VALUE (parm)))
3844 /* A primary class template can only have one
3845 parameter pack, at the end of the template
3848 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
3849 error ("parameter pack %qE must be at the end of the"
3850 " template parameter list", TREE_VALUE (parm));
3852 error ("parameter pack %qT must be at the end of the"
3853 " template parameter list",
3854 TREE_TYPE (TREE_VALUE (parm)));
3856 TREE_VALUE (TREE_VEC_ELT (inner_parms, i))
3864 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL)
3868 /* For an ordinary class template, default template arguments are
3869 allowed at the innermost level, e.g.:
3870 template <class T = int>
3872 but, in a partial specialization, they're not allowed even
3873 there, as we have in [temp.class.spec]:
3875 The template parameter list of a specialization shall not
3876 contain default template argument values.
3878 So, for a partial specialization, or for a function template
3879 (in C++98/C++03), we look at all of them. */
3882 /* But, for a primary class template that is not a partial
3883 specialization we look at all template parameters except the
3885 parms = TREE_CHAIN (parms);
3887 /* Figure out what error message to issue. */
3888 if (is_friend_decl == 2)
3889 msg = "default template arguments may not be used in function template friend re-declaration";
3890 else if (is_friend_decl)
3891 msg = "default template arguments may not be used in function template friend declarations";
3892 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98))
3893 msg = "default template arguments may not be used in function templates";
3894 else if (is_partial)
3895 msg = "default template arguments may not be used in partial specializations";
3897 msg = "default argument for template parameter for class enclosing %qD";
3899 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
3900 /* If we're inside a class definition, there's no need to
3901 examine the parameters to the class itself. On the one
3902 hand, they will be checked when the class is defined, and,
3903 on the other, default arguments are valid in things like:
3904 template <class T = double>
3905 struct S { template <class U> void f(U); };
3906 Here the default argument for `S' has no bearing on the
3907 declaration of `f'. */
3908 last_level_to_check = template_class_depth (current_class_type) + 1;
3910 /* Check everything. */
3911 last_level_to_check = 0;
3913 for (parm_level = parms;
3914 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
3915 parm_level = TREE_CHAIN (parm_level))
3917 tree inner_parms = TREE_VALUE (parm_level);
3921 ntparms = TREE_VEC_LENGTH (inner_parms);
3922 for (i = 0; i < ntparms; ++i)
3924 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node)
3927 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
3932 if (is_friend_decl == 2)
3939 /* Clear out the default argument so that we are not
3941 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
3945 /* At this point, if we're still interested in issuing messages,
3946 they must apply to classes surrounding the object declared. */
3948 msg = "default argument for template parameter for class enclosing %qD";
3954 /* Worker for push_template_decl_real, called via
3955 for_each_template_parm. DATA is really an int, indicating the
3956 level of the parameters we are interested in. If T is a template
3957 parameter of that level, return nonzero. */
3960 template_parm_this_level_p (tree t, void* data)
3962 int this_level = *(int *)data;
3965 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
3966 level = TEMPLATE_PARM_LEVEL (t);
3968 level = TEMPLATE_TYPE_LEVEL (t);
3969 return level == this_level;
3972 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
3973 parameters given by current_template_args, or reuses a
3974 previously existing one, if appropriate. Returns the DECL, or an
3975 equivalent one, if it is replaced via a call to duplicate_decls.
3977 If IS_FRIEND is true, DECL is a friend declaration. */
3980 push_template_decl_real (tree decl, bool is_friend)
3988 int new_template_p = 0;
3989 /* True if the template is a member template, in the sense of
3991 bool member_template_p = false;
3993 if (decl == error_mark_node || !current_template_parms)
3994 return error_mark_node;
3996 /* See if this is a partial specialization. */
3997 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
3998 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3999 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
4001 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
4005 /* For a friend, we want the context of the friend function, not
4006 the type of which it is a friend. */
4007 ctx = DECL_CONTEXT (decl);
4008 else if (CP_DECL_CONTEXT (decl)
4009 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
4010 /* In the case of a virtual function, we want the class in which
4012 ctx = CP_DECL_CONTEXT (decl);
4014 /* Otherwise, if we're currently defining some class, the DECL
4015 is assumed to be a member of the class. */
4016 ctx = current_scope ();
4018 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
4021 if (!DECL_CONTEXT (decl))
4022 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4024 /* See if this is a primary template. */
4025 if (is_friend && ctx)
4026 /* A friend template that specifies a class context, i.e.
4027 template <typename T> friend void A<T>::f();
4031 primary = template_parm_scope_p ();
4035 if (DECL_CLASS_SCOPE_P (decl))
4036 member_template_p = true;
4037 if (TREE_CODE (decl) == TYPE_DECL
4038 && ANON_AGGRNAME_P (DECL_NAME (decl)))
4040 error ("template class without a name");
4041 return error_mark_node;
4043 else if (TREE_CODE (decl) == FUNCTION_DECL)
4045 if (DECL_DESTRUCTOR_P (decl))
4049 A destructor shall not be a member template. */
4050 error ("destructor %qD declared as member template", decl);
4051 return error_mark_node;
4053 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
4054 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
4055 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
4056 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
4057 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
4058 == void_list_node)))
4060 /* [basic.stc.dynamic.allocation]
4062 An allocation function can be a function
4063 template. ... Template allocation functions shall
4064 have two or more parameters. */
4065 error ("invalid template declaration of %qD", decl);
4066 return error_mark_node;
4069 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4070 && CLASS_TYPE_P (TREE_TYPE (decl)))
4074 error ("template declaration of %q#D", decl);
4075 return error_mark_node;
4079 /* Check to see that the rules regarding the use of default
4080 arguments are not being violated. */
4081 check_default_tmpl_args (decl, current_template_parms,
4082 primary, is_partial, /*is_friend_decl=*/0);
4084 /* Ensure that there are no parameter packs in the type of this
4085 declaration that have not been expanded. */
4086 if (TREE_CODE (decl) == FUNCTION_DECL)
4088 /* Check each of the arguments individually to see if there are
4089 any bare parameter packs. */
4090 tree type = TREE_TYPE (decl);
4091 tree arg = DECL_ARGUMENTS (decl);
4092 tree argtype = TYPE_ARG_TYPES (type);
4094 while (arg && argtype)
4096 if (!FUNCTION_PARAMETER_PACK_P (arg)
4097 && check_for_bare_parameter_packs (TREE_TYPE (arg)))
4099 /* This is a PARM_DECL that contains unexpanded parameter
4100 packs. We have already complained about this in the
4101 check_for_bare_parameter_packs call, so just replace
4102 these types with ERROR_MARK_NODE. */
4103 TREE_TYPE (arg) = error_mark_node;
4104 TREE_VALUE (argtype) = error_mark_node;
4107 arg = TREE_CHAIN (arg);
4108 argtype = TREE_CHAIN (argtype);
4111 /* Check for bare parameter packs in the return type and the
4112 exception specifiers. */
4113 if (check_for_bare_parameter_packs (TREE_TYPE (type)))
4114 /* Errors were already issued, set return type to int
4115 as the frontend doesn't expect error_mark_node as
4117 TREE_TYPE (type) = integer_type_node;
4118 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type)))
4119 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE;
4121 else if (check_for_bare_parameter_packs (TREE_TYPE (decl)))
4123 TREE_TYPE (decl) = error_mark_node;
4124 return error_mark_node;
4128 return process_partial_specialization (decl);
4130 args = current_template_args ();
4133 || TREE_CODE (ctx) == FUNCTION_DECL
4134 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
4135 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
4137 if (DECL_LANG_SPECIFIC (decl)
4138 && DECL_TEMPLATE_INFO (decl)
4139 && DECL_TI_TEMPLATE (decl))
4140 tmpl = DECL_TI_TEMPLATE (decl);
4141 /* If DECL is a TYPE_DECL for a class-template, then there won't
4142 be DECL_LANG_SPECIFIC. The information equivalent to
4143 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
4144 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
4145 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
4146 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
4148 /* Since a template declaration already existed for this
4149 class-type, we must be redeclaring it here. Make sure
4150 that the redeclaration is valid. */
4151 redeclare_class_template (TREE_TYPE (decl),
4152 current_template_parms);
4153 /* We don't need to create a new TEMPLATE_DECL; just use the
4154 one we already had. */
4155 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
4159 tmpl = build_template_decl (decl, current_template_parms,
4163 if (DECL_LANG_SPECIFIC (decl)
4164 && DECL_TEMPLATE_SPECIALIZATION (decl))
4166 /* A specialization of a member template of a template
4168 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
4169 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
4170 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
4176 tree a, t, current, parms;
4178 tree tinfo = get_template_info (decl);
4182 error ("template definition of non-template %q#D", decl);
4183 return error_mark_node;
4186 tmpl = TI_TEMPLATE (tinfo);
4188 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
4189 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
4190 && DECL_TEMPLATE_SPECIALIZATION (decl)
4191 && DECL_MEMBER_TEMPLATE_P (tmpl))
4195 /* The declaration is a specialization of a member
4196 template, declared outside the class. Therefore, the
4197 innermost template arguments will be NULL, so we
4198 replace them with the arguments determined by the
4199 earlier call to check_explicit_specialization. */
4200 args = DECL_TI_ARGS (decl);
4203 = build_template_decl (decl, current_template_parms,
4205 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
4206 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
4207 DECL_TI_TEMPLATE (decl) = new_tmpl;
4208 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
4209 DECL_TEMPLATE_INFO (new_tmpl)
4210 = tree_cons (tmpl, args, NULL_TREE);
4212 register_specialization (new_tmpl,
4213 most_general_template (tmpl),
4219 /* Make sure the template headers we got make sense. */
4221 parms = DECL_TEMPLATE_PARMS (tmpl);
4222 i = TMPL_PARMS_DEPTH (parms);
4223 if (TMPL_ARGS_DEPTH (args) != i)
4225 error ("expected %d levels of template parms for %q#D, got %d",
4226 i, decl, TMPL_ARGS_DEPTH (args));
4229 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
4231 a = TMPL_ARGS_LEVEL (args, i);
4232 t = INNERMOST_TEMPLATE_PARMS (parms);
4234 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
4236 if (current == decl)
4237 error ("got %d template parameters for %q#D",
4238 TREE_VEC_LENGTH (a), decl);
4240 error ("got %d template parameters for %q#T",
4241 TREE_VEC_LENGTH (a), current);
4242 error (" but %d required", TREE_VEC_LENGTH (t));
4243 return error_mark_node;
4246 if (current == decl)
4249 current = (TYPE_P (current)
4250 ? TYPE_CONTEXT (current)
4251 : DECL_CONTEXT (current));
4254 /* Check that the parms are used in the appropriate qualifying scopes
4255 in the declarator. */
4256 if (!comp_template_args
4258 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl)))))
4261 template arguments to %qD do not match original template %qD",
4262 decl, DECL_TEMPLATE_RESULT (tmpl));
4263 if (!uses_template_parms (TI_ARGS (tinfo)))
4264 inform (input_location, "use template<> for an explicit specialization");
4265 /* Avoid crash in import_export_decl. */
4266 DECL_INTERFACE_KNOWN (decl) = 1;
4267 return error_mark_node;
4271 DECL_TEMPLATE_RESULT (tmpl) = decl;
4272 TREE_TYPE (tmpl) = TREE_TYPE (decl);
4274 /* Push template declarations for global functions and types. Note
4275 that we do not try to push a global template friend declared in a
4276 template class; such a thing may well depend on the template
4277 parameters of the class. */
4278 if (new_template_p && !ctx
4279 && !(is_friend && template_class_depth (current_class_type) > 0))
4281 tmpl = pushdecl_namespace_level (tmpl, is_friend);
4282 if (tmpl == error_mark_node)
4283 return error_mark_node;
4285 /* Hide template friend classes that haven't been declared yet. */
4286 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
4288 DECL_ANTICIPATED (tmpl) = 1;
4289 DECL_FRIEND_P (tmpl) = 1;
4295 tree parms = DECL_TEMPLATE_PARMS (tmpl);
4298 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
4299 if (DECL_CONV_FN_P (tmpl))
4301 int depth = TMPL_PARMS_DEPTH (parms);
4303 /* It is a conversion operator. See if the type converted to
4304 depends on innermost template operands. */
4306 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
4308 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
4311 /* Give template template parms a DECL_CONTEXT of the template
4312 for which they are a parameter. */
4313 parms = INNERMOST_TEMPLATE_PARMS (parms);
4314 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
4316 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4317 if (TREE_CODE (parm) == TEMPLATE_DECL)
4318 DECL_CONTEXT (parm) = tmpl;
4322 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
4323 back to its most general template. If TMPL is a specialization,
4324 ARGS may only have the innermost set of arguments. Add the missing
4325 argument levels if necessary. */
4326 if (DECL_TEMPLATE_INFO (tmpl))
4327 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
4329 info = tree_cons (tmpl, args, NULL_TREE);
4331 if (DECL_IMPLICIT_TYPEDEF_P (decl))
4332 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
4333 else if (DECL_LANG_SPECIFIC (decl))
4334 DECL_TEMPLATE_INFO (decl) = info;
4336 return DECL_TEMPLATE_RESULT (tmpl);
4340 push_template_decl (tree decl)
4342 return push_template_decl_real (decl, false);
4345 /* Called when a class template TYPE is redeclared with the indicated
4346 template PARMS, e.g.:
4348 template <class T> struct S;
4349 template <class T> struct S {}; */
4352 redeclare_class_template (tree type, tree parms)
4358 if (!TYPE_TEMPLATE_INFO (type))
4360 error ("%qT is not a template type", type);
4364 tmpl = TYPE_TI_TEMPLATE (type);
4365 if (!PRIMARY_TEMPLATE_P (tmpl))
4366 /* The type is nested in some template class. Nothing to worry
4367 about here; there are no new template parameters for the nested
4373 error ("template specifiers not specified in declaration of %qD",
4378 parms = INNERMOST_TEMPLATE_PARMS (parms);
4379 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
4381 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
4383 error ("redeclared with %d template parameter(s)",
4384 TREE_VEC_LENGTH (parms));
4385 inform (input_location, "previous declaration %q+D used %d template parameter(s)",
4386 tmpl, TREE_VEC_LENGTH (tmpl_parms));
4390 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
4397 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node
4398 || TREE_VEC_ELT (parms, i) == error_mark_node)
4401 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
4402 parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4403 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
4404 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
4406 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
4408 if (tmpl_parm != error_mark_node
4409 && (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
4410 || (TREE_CODE (tmpl_parm) != TYPE_DECL
4411 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm)))
4412 || (TREE_CODE (tmpl_parm) != PARM_DECL
4413 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm))
4414 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))))
4415 || (TREE_CODE (tmpl_parm) == PARM_DECL
4416 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm))
4417 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))))))
4419 error ("template parameter %q+#D", tmpl_parm);
4420 error ("redeclared here as %q#D", parm);
4424 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
4426 /* We have in [temp.param]:
4428 A template-parameter may not be given default arguments
4429 by two different declarations in the same scope. */
4430 error ("redefinition of default argument for %q#D", parm);
4431 inform (input_location, "%Joriginal definition appeared here", tmpl_parm);
4435 if (parm_default != NULL_TREE)
4436 /* Update the previous template parameters (which are the ones
4437 that will really count) with the new default value. */
4438 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
4439 else if (tmpl_default != NULL_TREE)
4440 /* Update the new parameters, too; they'll be used as the
4441 parameters for any members. */
4442 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
4448 /* Simplify EXPR if it is a non-dependent expression. Returns the
4449 (possibly simplified) expression. */
4452 fold_non_dependent_expr (tree expr)
4454 if (expr == NULL_TREE)
4457 /* If we're in a template, but EXPR isn't value dependent, simplify
4458 it. We're supposed to treat:
4460 template <typename T> void f(T[1 + 1]);
4461 template <typename T> void f(T[2]);
4463 as two declarations of the same function, for example. */
4464 if (processing_template_decl
4465 && !type_dependent_expression_p (expr)
4466 && !value_dependent_expression_p (expr))
4468 HOST_WIDE_INT saved_processing_template_decl;
4470 saved_processing_template_decl = processing_template_decl;
4471 processing_template_decl = 0;
4472 expr = tsubst_copy_and_build (expr,
4475 /*in_decl=*/NULL_TREE,
4476 /*function_p=*/false,
4477 /*integral_constant_expression_p=*/true);
4478 processing_template_decl = saved_processing_template_decl;
4483 /* EXPR is an expression which is used in a constant-expression context.
4484 For instance, it could be a VAR_DECL with a constant initializer.
4485 Extract the innermost constant expression.
4487 This is basically a more powerful version of
4488 integral_constant_value, which can be used also in templates where
4489 initializers can maintain a syntactic rather than semantic form
4490 (even if they are non-dependent, for access-checking purposes). */
4493 fold_decl_constant_value (tree expr)
4495 tree const_expr = expr;
4498 expr = fold_non_dependent_expr (const_expr);
4499 const_expr = integral_constant_value (expr);
4501 while (expr != const_expr);
4506 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
4507 must be a function or a pointer-to-function type, as specified
4508 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
4509 and check that the resulting function has external linkage. */
4512 convert_nontype_argument_function (tree type, tree expr)
4517 fn = instantiate_type (type, fns, tf_none);
4518 if (fn == error_mark_node)
4519 return error_mark_node;
4522 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
4523 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
4524 if (TREE_CODE (fn_no_ptr) == BASELINK)
4525 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr);
4527 /* [temp.arg.nontype]/1
4529 A template-argument for a non-type, non-template template-parameter
4532 -- the address of an object or function with external linkage. */
4533 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
4535 error ("%qE is not a valid template argument for type %qT "
4536 "because function %qD has not external linkage",
4537 expr, type, fn_no_ptr);
4544 /* Attempt to convert the non-type template parameter EXPR to the
4545 indicated TYPE. If the conversion is successful, return the
4546 converted value. If the conversion is unsuccessful, return
4547 NULL_TREE if we issued an error message, or error_mark_node if we
4548 did not. We issue error messages for out-and-out bad template
4549 parameters, but not simply because the conversion failed, since we
4550 might be just trying to do argument deduction. Both TYPE and EXPR
4551 must be non-dependent.
4553 The conversion follows the special rules described in
4554 [temp.arg.nontype], and it is much more strict than an implicit
4557 This function is called twice for each template argument (see
4558 lookup_template_class for a more accurate description of this
4559 problem). This means that we need to handle expressions which
4560 are not valid in a C++ source, but can be created from the
4561 first call (for instance, casts to perform conversions). These
4562 hacks can go away after we fix the double coercion problem. */
4565 convert_nontype_argument (tree type, tree expr)
4569 /* Detect immediately string literals as invalid non-type argument.
4570 This special-case is not needed for correctness (we would easily
4571 catch this later), but only to provide better diagnostic for this
4572 common user mistake. As suggested by DR 100, we do not mention
4573 linkage issues in the diagnostic as this is not the point. */
4574 if (TREE_CODE (expr) == STRING_CST)
4576 error ("%qE is not a valid template argument for type %qT "
4577 "because string literals can never be used in this context",
4582 /* If we are in a template, EXPR may be non-dependent, but still
4583 have a syntactic, rather than semantic, form. For example, EXPR
4584 might be a SCOPE_REF, rather than the VAR_DECL to which the
4585 SCOPE_REF refers. Preserving the qualifying scope is necessary
4586 so that access checking can be performed when the template is
4587 instantiated -- but here we need the resolved form so that we can
4588 convert the argument. */
4589 expr = fold_non_dependent_expr (expr);
4590 if (error_operand_p (expr))
4591 return error_mark_node;
4592 expr_type = TREE_TYPE (expr);
4594 /* HACK: Due to double coercion, we can get a
4595 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
4596 which is the tree that we built on the first call (see
4597 below when coercing to reference to object or to reference to
4598 function). We just strip everything and get to the arg.
4599 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
4601 if (TREE_CODE (expr) == NOP_EXPR)
4603 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
4605 /* ??? Maybe we could use convert_from_reference here, but we
4606 would need to relax its constraints because the NOP_EXPR
4607 could actually change the type to something more cv-qualified,
4608 and this is not folded by convert_from_reference. */
4609 tree addr = TREE_OPERAND (expr, 0);
4610 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
4611 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
4612 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
4613 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4614 (TREE_TYPE (expr_type),
4615 TREE_TYPE (TREE_TYPE (addr))));
4617 expr = TREE_OPERAND (addr, 0);
4618 expr_type = TREE_TYPE (expr);
4621 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
4622 parameter is a pointer to object, through decay and
4623 qualification conversion. Let's strip everything. */
4624 else if (TYPE_PTROBV_P (type))
4627 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
4628 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
4629 /* Skip the ADDR_EXPR only if it is part of the decay for
4630 an array. Otherwise, it is part of the original argument
4631 in the source code. */
4632 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
4633 expr = TREE_OPERAND (expr, 0);
4634 expr_type = TREE_TYPE (expr);
4638 /* [temp.arg.nontype]/5, bullet 1
4640 For a non-type template-parameter of integral or enumeration type,
4641 integral promotions (_conv.prom_) and integral conversions
4642 (_conv.integral_) are applied. */
4643 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
4645 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (expr_type))
4646 return error_mark_node;
4648 expr = fold_decl_constant_value (expr);
4649 /* Notice that there are constant expressions like '4 % 0' which
4650 do not fold into integer constants. */
4651 if (TREE_CODE (expr) != INTEGER_CST)
4653 error ("%qE is not a valid template argument for type %qT "
4654 "because it is a non-constant expression", expr, type);
4658 /* At this point, an implicit conversion does what we want,
4659 because we already know that the expression is of integral
4661 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
4662 if (expr == error_mark_node)
4663 return error_mark_node;
4665 /* Conversion was allowed: fold it to a bare integer constant. */
4668 /* [temp.arg.nontype]/5, bullet 2
4670 For a non-type template-parameter of type pointer to object,
4671 qualification conversions (_conv.qual_) and the array-to-pointer
4672 conversion (_conv.array_) are applied. */
4673 else if (TYPE_PTROBV_P (type))
4675 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
4677 A template-argument for a non-type, non-template template-parameter
4678 shall be one of: [...]
4680 -- the name of a non-type template-parameter;
4681 -- the address of an object or function with external linkage, [...]
4682 expressed as "& id-expression" where the & is optional if the name
4683 refers to a function or array, or if the corresponding
4684 template-parameter is a reference.
4686 Here, we do not care about functions, as they are invalid anyway
4687 for a parameter of type pointer-to-object. */
4689 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr))
4690 /* Non-type template parameters are OK. */
4692 else if (TREE_CODE (expr) != ADDR_EXPR
4693 && TREE_CODE (expr_type) != ARRAY_TYPE)
4695 if (TREE_CODE (expr) == VAR_DECL)
4697 error ("%qD is not a valid template argument "
4698 "because %qD is a variable, not the address of "
4703 /* Other values, like integer constants, might be valid
4704 non-type arguments of some other type. */
4705 return error_mark_node;
4711 decl = ((TREE_CODE (expr) == ADDR_EXPR)
4712 ? TREE_OPERAND (expr, 0) : expr);
4713 if (TREE_CODE (decl) != VAR_DECL)
4715 error ("%qE is not a valid template argument of type %qT "
4716 "because %qE is not a variable",
4720 else if (!DECL_EXTERNAL_LINKAGE_P (decl))
4722 error ("%qE is not a valid template argument of type %qT "
4723 "because %qD does not have external linkage",
4729 expr = decay_conversion (expr);
4730 if (expr == error_mark_node)
4731 return error_mark_node;
4733 expr = perform_qualification_conversions (type, expr);
4734 if (expr == error_mark_node)
4735 return error_mark_node;
4737 /* [temp.arg.nontype]/5, bullet 3
4739 For a non-type template-parameter of type reference to object, no
4740 conversions apply. The type referred to by the reference may be more
4741 cv-qualified than the (otherwise identical) type of the
4742 template-argument. The template-parameter is bound directly to the
4743 template-argument, which must be an lvalue. */
4744 else if (TYPE_REF_OBJ_P (type))
4746 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
4748 return error_mark_node;
4750 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
4752 error ("%qE is not a valid template argument for type %qT "
4753 "because of conflicts in cv-qualification", expr, type);
4757 if (!real_lvalue_p (expr))
4759 error ("%qE is not a valid template argument for type %qT "
4760 "because it is not an lvalue", expr, type);
4764 /* [temp.arg.nontype]/1
4766 A template-argument for a non-type, non-template template-parameter
4767 shall be one of: [...]
4769 -- the address of an object or function with external linkage. */
4770 if (!DECL_EXTERNAL_LINKAGE_P (expr))
4772 error ("%qE is not a valid template argument for type %qT "
4773 "because object %qD has not external linkage",
4778 expr = build_nop (type, build_address (expr));
4780 /* [temp.arg.nontype]/5, bullet 4
4782 For a non-type template-parameter of type pointer to function, only
4783 the function-to-pointer conversion (_conv.func_) is applied. If the
4784 template-argument represents a set of overloaded functions (or a
4785 pointer to such), the matching function is selected from the set
4787 else if (TYPE_PTRFN_P (type))
4789 /* If the argument is a template-id, we might not have enough
4790 context information to decay the pointer. */
4791 if (!type_unknown_p (expr_type))
4793 expr = decay_conversion (expr);
4794 if (expr == error_mark_node)
4795 return error_mark_node;
4798 expr = convert_nontype_argument_function (type, expr);
4799 if (!expr || expr == error_mark_node)
4802 if (TREE_CODE (expr) != ADDR_EXPR)
4804 error ("%qE is not a valid template argument for type %qT", expr, type);
4805 error ("it must be the address of a function with external linkage");
4809 /* [temp.arg.nontype]/5, bullet 5
4811 For a non-type template-parameter of type reference to function, no
4812 conversions apply. If the template-argument represents a set of
4813 overloaded functions, the matching function is selected from the set
4815 else if (TYPE_REFFN_P (type))
4817 if (TREE_CODE (expr) == ADDR_EXPR)
4819 error ("%qE is not a valid template argument for type %qT "
4820 "because it is a pointer", expr, type);
4821 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0));
4825 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
4826 if (!expr || expr == error_mark_node)
4829 expr = build_nop (type, build_address (expr));
4831 /* [temp.arg.nontype]/5, bullet 6
4833 For a non-type template-parameter of type pointer to member function,
4834 no conversions apply. If the template-argument represents a set of
4835 overloaded member functions, the matching member function is selected
4836 from the set (_over.over_). */
4837 else if (TYPE_PTRMEMFUNC_P (type))
4839 expr = instantiate_type (type, expr, tf_none);
4840 if (expr == error_mark_node)
4841 return error_mark_node;
4843 /* There is no way to disable standard conversions in
4844 resolve_address_of_overloaded_function (called by
4845 instantiate_type). It is possible that the call succeeded by
4846 converting &B::I to &D::I (where B is a base of D), so we need
4847 to reject this conversion here.
4849 Actually, even if there was a way to disable standard conversions,
4850 it would still be better to reject them here so that we can
4851 provide a superior diagnostic. */
4852 if (!same_type_p (TREE_TYPE (expr), type))
4854 /* Make sure we are just one standard conversion off. */
4855 gcc_assert (can_convert (type, TREE_TYPE (expr)));
4856 error ("%qE is not a valid template argument for type %qT "
4857 "because it is of type %qT", expr, type,
4859 inform (input_location, "standard conversions are not allowed in this context");
4863 /* [temp.arg.nontype]/5, bullet 7
4865 For a non-type template-parameter of type pointer to data member,
4866 qualification conversions (_conv.qual_) are applied. */
4867 else if (TYPE_PTRMEM_P (type))
4869 expr = perform_qualification_conversions (type, expr);
4870 if (expr == error_mark_node)
4873 /* A template non-type parameter must be one of the above. */
4877 /* Sanity check: did we actually convert the argument to the
4879 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
4883 /* Subroutine of coerce_template_template_parms, which returns 1 if
4884 PARM_PARM and ARG_PARM match using the rule for the template
4885 parameters of template template parameters. Both PARM and ARG are
4886 template parameters; the rest of the arguments are the same as for
4887 coerce_template_template_parms.
4890 coerce_template_template_parm (tree parm,
4892 tsubst_flags_t complain,
4896 if (arg == NULL_TREE || arg == error_mark_node
4897 || parm == NULL_TREE || parm == error_mark_node)
4900 if (TREE_CODE (arg) != TREE_CODE (parm))
4903 switch (TREE_CODE (parm))
4906 /* We encounter instantiations of templates like
4907 template <template <template <class> class> class TT>
4910 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
4911 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
4913 if (!coerce_template_template_parms
4914 (parmparm, argparm, complain, in_decl, outer_args))
4920 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg))
4921 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
4922 /* Argument is a parameter pack but parameter is not. */
4927 /* The tsubst call is used to handle cases such as
4929 template <int> class C {};
4930 template <class T, template <T> class TT> class D {};
4933 i.e. the parameter list of TT depends on earlier parameters. */
4934 if (!uses_template_parms (TREE_TYPE (arg))
4936 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
4940 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg))
4941 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
4942 /* Argument is a parameter pack but parameter is not. */
4955 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
4956 template template parameters. Both PARM_PARMS and ARG_PARMS are
4957 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
4960 Consider the example:
4961 template <class T> class A;
4962 template<template <class U> class TT> class B;
4964 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are
4965 the parameters to A, and OUTER_ARGS contains A. */
4968 coerce_template_template_parms (tree parm_parms,
4970 tsubst_flags_t complain,
4974 int nparms, nargs, i;
4978 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
4979 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
4981 nparms = TREE_VEC_LENGTH (parm_parms);
4982 nargs = TREE_VEC_LENGTH (arg_parms);
4984 /* Determine whether we have a parameter pack at the end of the
4985 template template parameter's template parameter list. */
4986 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node)
4988 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1));
4990 if (parm == error_mark_node)
4993 switch (TREE_CODE (parm))
4997 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))
5002 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)))
5012 && !(variadic_p && nargs >= nparms - 1))
5015 /* Check all of the template parameters except the parameter pack at
5016 the end (if any). */
5017 for (i = 0; i < nparms - variadic_p; ++i)
5019 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node
5020 || TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5023 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5024 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5026 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5034 /* Check each of the template parameters in the template
5035 argument against the template parameter pack at the end of
5036 the template template parameter. */
5037 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node)
5040 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
5042 for (; i < nargs; ++i)
5044 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node)
5047 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
5049 if (!coerce_template_template_parm (parm, arg, complain, in_decl,
5058 /* Verifies that the deduced template arguments (in TARGS) for the
5059 template template parameters (in TPARMS) represent valid bindings,
5060 by comparing the template parameter list of each template argument
5061 to the template parameter list of its corresponding template
5062 template parameter, in accordance with DR150. This
5063 routine can only be called after all template arguments have been
5064 deduced. It will return TRUE if all of the template template
5065 parameter bindings are okay, FALSE otherwise. */
5067 template_template_parm_bindings_ok_p (tree tparms, tree targs)
5069 int i, ntparms = TREE_VEC_LENGTH (tparms);
5072 /* We're dealing with template parms in this process. */
5073 ++processing_template_decl;
5075 targs = INNERMOST_TEMPLATE_ARGS (targs);
5077 for (i = 0; i < ntparms; ++i)
5079 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
5080 tree targ = TREE_VEC_ELT (targs, i);
5082 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ)
5084 tree packed_args = NULL_TREE;
5087 if (ARGUMENT_PACK_P (targ))
5089 /* Look inside the argument pack. */
5090 packed_args = ARGUMENT_PACK_ARGS (targ);
5091 len = TREE_VEC_LENGTH (packed_args);
5094 for (idx = 0; idx < len; ++idx)
5096 tree targ_parms = NULL_TREE;
5099 /* Extract the next argument from the argument
5101 targ = TREE_VEC_ELT (packed_args, idx);
5103 if (PACK_EXPANSION_P (targ))
5104 /* Look at the pattern of the pack expansion. */
5105 targ = PACK_EXPANSION_PATTERN (targ);
5107 /* Extract the template parameters from the template
5109 if (TREE_CODE (targ) == TEMPLATE_DECL)
5110 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ);
5111 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM)
5112 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ));
5114 /* Verify that we can coerce the template template
5115 parameters from the template argument to the template
5116 parameter. This requires an exact match. */
5118 && !coerce_template_template_parms
5119 (DECL_INNERMOST_TEMPLATE_PARMS (tparm),
5134 --processing_template_decl;
5138 /* Convert the indicated template ARG as necessary to match the
5139 indicated template PARM. Returns the converted ARG, or
5140 error_mark_node if the conversion was unsuccessful. Error and
5141 warning messages are issued under control of COMPLAIN. This
5142 conversion is for the Ith parameter in the parameter list. ARGS is
5143 the full set of template arguments deduced so far. */
5146 convert_template_argument (tree parm,
5149 tsubst_flags_t complain,
5155 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
5157 if (TREE_CODE (arg) == TREE_LIST
5158 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
5160 /* The template argument was the name of some
5161 member function. That's usually
5162 invalid, but static members are OK. In any
5163 case, grab the underlying fields/functions
5164 and issue an error later if required. */
5165 orig_arg = TREE_VALUE (arg);
5166 TREE_TYPE (arg) = unknown_type_node;
5171 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
5172 requires_type = (TREE_CODE (parm) == TYPE_DECL
5173 || requires_tmpl_type);
5175 /* When determining whether an argument pack expansion is a template,
5176 look at the pattern. */
5177 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION)
5178 arg = PACK_EXPANSION_PATTERN (arg);
5181 ((TREE_CODE (arg) == TEMPLATE_DECL
5182 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
5183 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5184 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
5187 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
5188 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
5189 arg = TYPE_STUB_DECL (arg);
5191 is_type = TYPE_P (arg) || is_tmpl_type;
5193 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
5194 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
5196 permerror (input_location, "to refer to a type member of a template parameter, "
5197 "use %<typename %E%>", orig_arg);
5199 orig_arg = make_typename_type (TREE_OPERAND (arg, 0),
5200 TREE_OPERAND (arg, 1),
5202 complain & tf_error);
5206 if (is_type != requires_type)
5210 if (complain & tf_error)
5212 error ("type/value mismatch at argument %d in template "
5213 "parameter list for %qD",
5216 error (" expected a constant of type %qT, got %qT",
5218 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg));
5219 else if (requires_tmpl_type)
5220 error (" expected a class template, got %qE", orig_arg);
5222 error (" expected a type, got %qE", orig_arg);
5225 return error_mark_node;
5227 if (is_tmpl_type ^ requires_tmpl_type)
5229 if (in_decl && (complain & tf_error))
5231 error ("type/value mismatch at argument %d in template "
5232 "parameter list for %qD",
5235 error (" expected a type, got %qT", DECL_NAME (arg));
5237 error (" expected a class template, got %qT", orig_arg);
5239 return error_mark_node;
5244 if (requires_tmpl_type)
5246 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
5247 /* The number of argument required is not known yet.
5248 Just accept it for now. */
5249 val = TREE_TYPE (arg);
5252 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
5255 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
5257 if (coerce_template_template_parms (parmparm, argparm,
5263 /* TEMPLATE_TEMPLATE_PARM node is preferred over
5265 if (val != error_mark_node)
5267 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val))
5268 val = TREE_TYPE (val);
5269 else if (TREE_CODE (val) == TYPE_PACK_EXPANSION
5270 && DECL_TEMPLATE_TEMPLATE_PARM_P (arg))
5272 val = TREE_TYPE (arg);
5273 val = make_pack_expansion (val);
5279 if (in_decl && (complain & tf_error))
5281 error ("type/value mismatch at argument %d in "
5282 "template parameter list for %qD",
5284 error (" expected a template of type %qD, got %qD",
5288 val = error_mark_node;
5294 /* We only form one instance of each template specialization.
5295 Therefore, if we use a non-canonical variant (i.e., a
5296 typedef), any future messages referring to the type will use
5297 the typedef, which is confusing if those future uses do not
5298 themselves also use the typedef. */
5300 val = strip_typedefs (val);
5304 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
5306 if (invalid_nontype_parm_type_p (t, complain))
5307 return error_mark_node;
5309 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg))
5311 if (same_type_p (t, TREE_TYPE (orig_arg)))
5315 /* Not sure if this is reachable, but it doesn't hurt
5317 error ("type mismatch in nontype parameter pack");
5318 val = error_mark_node;
5321 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t))
5322 /* We used to call digest_init here. However, digest_init
5323 will report errors, which we don't want when complain
5324 is zero. More importantly, digest_init will try too
5325 hard to convert things: for example, `0' should not be
5326 converted to pointer type at this point according to
5327 the standard. Accepting this is not merely an
5328 extension, since deciding whether or not these
5329 conversions can occur is part of determining which
5330 function template to call, or whether a given explicit
5331 argument specification is valid. */
5332 val = convert_nontype_argument (t, orig_arg);
5336 if (val == NULL_TREE)
5337 val = error_mark_node;
5338 else if (val == error_mark_node && (complain & tf_error))
5339 error ("could not convert template argument %qE to %qT", orig_arg, t);
5345 /* Coerces the remaining template arguments in INNER_ARGS (from
5346 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS.
5347 Returns the coerced argument pack. PARM_IDX is the position of this
5348 parameter in the template parameter list. ARGS is the original
5349 template argument list. */
5351 coerce_template_parameter_pack (tree parms,
5359 tsubst_flags_t complain)
5361 tree parm = TREE_VEC_ELT (parms, parm_idx);
5362 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5365 tree packed_types = NULL_TREE;
5367 if (arg_idx > nargs)
5370 packed_args = make_tree_vec (nargs - arg_idx);
5372 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL
5373 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm))))
5375 /* When the template parameter is a non-type template
5376 parameter pack whose type uses parameter packs, we need
5377 to look at each of the template arguments
5378 separately. Build a vector of the types for these
5379 non-type template parameters in PACKED_TYPES. */
5381 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm)));
5382 packed_types = tsubst_pack_expansion (expansion, args,
5385 if (packed_types == error_mark_node)
5386 return error_mark_node;
5388 /* Check that we have the right number of arguments. */
5390 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))
5391 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types))
5394 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types);
5395 error ("wrong number of template arguments (%d, should be %d)",
5396 nargs, needed_parms);
5397 return error_mark_node;
5400 /* If we aren't able to check the actual arguments now
5401 (because they haven't been expanded yet), we can at least
5402 verify that all of the types used for the non-type
5403 template parameter pack are, in fact, valid for non-type
5404 template parameters. */
5406 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)))
5408 int j, len = TREE_VEC_LENGTH (packed_types);
5409 for (j = 0; j < len; ++j)
5411 tree t = TREE_VEC_ELT (packed_types, j);
5412 if (invalid_nontype_parm_type_p (t, complain))
5413 return error_mark_node;
5418 /* Convert the remaining arguments, which will be a part of the
5419 parameter pack "parm". */
5420 for (; arg_idx < nargs; ++arg_idx)
5422 tree arg = TREE_VEC_ELT (inner_args, arg_idx);
5423 tree actual_parm = TREE_VALUE (parm);
5425 if (packed_types && !PACK_EXPANSION_P (arg))
5427 /* When we have a vector of types (corresponding to the
5428 non-type template parameter pack that uses parameter
5429 packs in its type, as mention above), and the
5430 argument is not an expansion (which expands to a
5431 currently unknown number of arguments), clone the
5432 parm and give it the next type in PACKED_TYPES. */
5433 actual_parm = copy_node (actual_parm);
5434 TREE_TYPE (actual_parm) =
5435 TREE_VEC_ELT (packed_types, arg_idx - parm_idx);
5438 if (arg != error_mark_node)
5439 arg = convert_template_argument (actual_parm,
5440 arg, new_args, complain, parm_idx,
5442 if (arg == error_mark_node)
5444 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg;
5447 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL
5448 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL)
5449 argument_pack = make_node (TYPE_ARGUMENT_PACK);
5452 argument_pack = make_node (NONTYPE_ARGUMENT_PACK);
5453 TREE_TYPE (argument_pack)
5454 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl);
5455 TREE_CONSTANT (argument_pack) = 1;
5458 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args);
5459 return argument_pack;
5462 /* Convert all template arguments to their appropriate types, and
5463 return a vector containing the innermost resulting template
5464 arguments. If any error occurs, return error_mark_node. Error and
5465 warning messages are issued under control of COMPLAIN.
5467 If REQUIRE_ALL_ARGS is false, argument deduction will be performed
5468 for arguments not specified in ARGS. Otherwise, if
5469 USE_DEFAULT_ARGS is true, default arguments will be used to fill in
5470 unspecified arguments. If REQUIRE_ALL_ARGS is true, but
5471 USE_DEFAULT_ARGS is false, then all arguments must be specified in
5475 coerce_template_parms (tree parms,
5478 tsubst_flags_t complain,
5479 bool require_all_args,
5480 bool use_default_args)
5482 int nparms, nargs, parm_idx, arg_idx, lost = 0;
5485 tree new_inner_args;
5486 int saved_unevaluated_operand;
5487 int saved_inhibit_evaluation_warnings;
5489 /* When used as a boolean value, indicates whether this is a
5490 variadic template parameter list. Since it's an int, we can also
5491 subtract it from nparms to get the number of non-variadic
5495 nparms = TREE_VEC_LENGTH (parms);
5497 /* Determine if there are any parameter packs. */
5498 for (parm_idx = 0; parm_idx < nparms; ++parm_idx)
5500 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx));
5501 if (template_parameter_pack_p (tparm))
5505 inner_args = INNERMOST_TEMPLATE_ARGS (args);
5506 /* If there are 0 or 1 parameter packs, we need to expand any argument
5507 packs so that we can deduce a parameter pack from some non-packed args
5508 followed by an argument pack, as in variadic85.C. If there are more
5509 than that, we need to leave argument packs intact so the arguments are
5510 assigned to the right parameter packs. This should only happen when
5511 dealing with a nested class inside a partial specialization of a class
5512 template, as in variadic92.C. */
5513 if (variadic_p <= 1)
5514 inner_args = expand_template_argument_pack (inner_args);
5516 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
5517 if ((nargs > nparms && !variadic_p)
5518 || (nargs < nparms - variadic_p
5520 && (!use_default_args
5521 || (TREE_VEC_ELT (parms, nargs) != error_mark_node
5522 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs))))))
5524 if (complain & tf_error)
5526 const char *or_more = "";
5529 or_more = " or more";
5533 error ("wrong number of template arguments (%d, should be %d%s)",
5534 nargs, nparms, or_more);
5537 error ("provided for %q+D", in_decl);
5540 return error_mark_node;
5543 /* We need to evaluate the template arguments, even though this
5544 template-id may be nested within a "sizeof". */
5545 saved_unevaluated_operand = cp_unevaluated_operand;
5546 cp_unevaluated_operand = 0;
5547 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
5548 c_inhibit_evaluation_warnings = 0;
5549 new_inner_args = make_tree_vec (nparms);
5550 new_args = add_outermost_template_args (args, new_inner_args);
5551 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++)
5556 /* Get the Ith template parameter. */
5557 parm = TREE_VEC_ELT (parms, parm_idx);
5559 if (parm == error_mark_node)
5561 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node;
5565 /* Calculate the next argument. */
5566 if (arg_idx < nargs)
5567 arg = TREE_VEC_ELT (inner_args, arg_idx);
5571 if (template_parameter_pack_p (TREE_VALUE (parm))
5572 && !(arg && ARGUMENT_PACK_P (arg)))
5574 /* All remaining arguments will be placed in the
5575 template parameter pack PARM. */
5576 arg = coerce_template_parameter_pack (parms, parm_idx, args,
5577 inner_args, arg_idx,
5581 /* Store this argument. */
5582 if (arg == error_mark_node)
5584 TREE_VEC_ELT (new_inner_args, parm_idx) = arg;
5586 /* We are done with all of the arguments. */
5593 if (PACK_EXPANSION_P (arg))
5595 if (complain & tf_error)
5597 /* FIXME this restriction was removed by N2555; see
5599 /* If ARG is a pack expansion, but PARM is not a
5600 template parameter pack (if it were, we would have
5601 handled it above), we're trying to expand into a
5602 fixed-length argument list. */
5603 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION)
5604 sorry ("cannot expand %<%E%> into a fixed-length "
5605 "argument list", arg);
5607 sorry ("cannot expand %<%T%> into a fixed-length "
5608 "argument list", arg);
5610 return error_mark_node;
5613 else if (require_all_args)
5614 /* There must be a default arg in this case. */
5615 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
5620 if (arg == error_mark_node)
5622 if (complain & tf_error)
5623 error ("template argument %d is invalid", arg_idx + 1);
5626 /* This only occurs if there was an error in the template
5627 parameter list itself (which we would already have
5628 reported) that we are trying to recover from, e.g., a class
5629 template with a parameter list such as
5630 template<typename..., typename>. */
5631 return error_mark_node;
5633 arg = convert_template_argument (TREE_VALUE (parm),
5634 arg, new_args, complain,
5637 if (arg == error_mark_node)
5639 TREE_VEC_ELT (new_inner_args, arg_idx) = arg;
5641 cp_unevaluated_operand = saved_unevaluated_operand;
5642 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
5645 return error_mark_node;
5647 return new_inner_args;
5650 /* Returns 1 if template args OT and NT are equivalent. */
5653 template_args_equal (tree ot, tree nt)
5658 if (TREE_CODE (nt) == TREE_VEC)
5659 /* For member templates */
5660 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
5661 else if (PACK_EXPANSION_P (ot))
5662 return PACK_EXPANSION_P (nt)
5663 && template_args_equal (PACK_EXPANSION_PATTERN (ot),
5664 PACK_EXPANSION_PATTERN (nt));
5665 else if (ARGUMENT_PACK_P (ot))
5670 if (!ARGUMENT_PACK_P (nt))
5673 opack = ARGUMENT_PACK_ARGS (ot);
5674 npack = ARGUMENT_PACK_ARGS (nt);
5675 len = TREE_VEC_LENGTH (opack);
5676 if (TREE_VEC_LENGTH (npack) != len)
5678 for (i = 0; i < len; ++i)
5679 if (!template_args_equal (TREE_VEC_ELT (opack, i),
5680 TREE_VEC_ELT (npack, i)))
5684 else if (TYPE_P (nt))
5685 return TYPE_P (ot) && same_type_p (ot, nt);
5686 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
5689 return cp_tree_equal (ot, nt);
5692 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
5693 of template arguments. Returns 0 otherwise. */
5696 comp_template_args (tree oldargs, tree newargs)
5700 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
5703 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
5705 tree nt = TREE_VEC_ELT (newargs, i);
5706 tree ot = TREE_VEC_ELT (oldargs, i);
5708 if (! template_args_equal (ot, nt))
5715 add_pending_template (tree d)
5717 tree ti = (TYPE_P (d)
5718 ? CLASSTYPE_TEMPLATE_INFO (d)
5719 : DECL_TEMPLATE_INFO (d));
5720 struct pending_template *pt;
5723 if (TI_PENDING_TEMPLATE_FLAG (ti))
5726 /* We are called both from instantiate_decl, where we've already had a
5727 tinst_level pushed, and instantiate_template, where we haven't.
5729 level = !current_tinst_level || current_tinst_level->decl != d;
5732 push_tinst_level (d);
5734 pt = GGC_NEW (struct pending_template);
5736 pt->tinst = current_tinst_level;
5737 if (last_pending_template)
5738 last_pending_template->next = pt;
5740 pending_templates = pt;
5742 last_pending_template = pt;
5744 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
5751 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
5752 ARGLIST. Valid choices for FNS are given in the cp-tree.def
5753 documentation for TEMPLATE_ID_EXPR. */
5756 lookup_template_function (tree fns, tree arglist)
5760 if (fns == error_mark_node || arglist == error_mark_node)
5761 return error_mark_node;
5763 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
5764 gcc_assert (fns && (is_overloaded_fn (fns)
5765 || TREE_CODE (fns) == IDENTIFIER_NODE));
5767 if (BASELINK_P (fns))
5769 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
5771 BASELINK_FUNCTIONS (fns),
5776 type = TREE_TYPE (fns);
5777 if (TREE_CODE (fns) == OVERLOAD || !type)
5778 type = unknown_type_node;
5780 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
5783 /* Within the scope of a template class S<T>, the name S gets bound
5784 (in build_self_reference) to a TYPE_DECL for the class, not a
5785 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
5786 or one of its enclosing classes, and that type is a template,
5787 return the associated TEMPLATE_DECL. Otherwise, the original
5788 DECL is returned. */
5791 maybe_get_template_decl_from_type_decl (tree decl)
5793 return (decl != NULL_TREE
5794 && TREE_CODE (decl) == TYPE_DECL
5795 && DECL_ARTIFICIAL (decl)
5796 && CLASS_TYPE_P (TREE_TYPE (decl))
5797 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
5798 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
5801 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
5802 parameters, find the desired type.
5804 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
5806 IN_DECL, if non-NULL, is the template declaration we are trying to
5809 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
5810 the class we are looking up.
5812 Issue error and warning messages under control of COMPLAIN.
5814 If the template class is really a local class in a template
5815 function, then the FUNCTION_CONTEXT is the function in which it is
5818 ??? Note that this function is currently called *twice* for each
5819 template-id: the first time from the parser, while creating the
5820 incomplete type (finish_template_type), and the second type during the
5821 real instantiation (instantiate_template_class). This is surely something
5822 that we want to avoid. It also causes some problems with argument
5823 coercion (see convert_nontype_argument for more information on this). */
5826 lookup_template_class (tree d1,
5831 tsubst_flags_t complain)
5833 tree templ = NULL_TREE, parmlist;
5840 timevar_push (TV_NAME_LOOKUP);
5842 if (TREE_CODE (d1) == IDENTIFIER_NODE)
5844 tree value = innermost_non_namespace_value (d1);
5845 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
5850 push_decl_namespace (context);
5851 templ = lookup_name (d1);
5852 templ = maybe_get_template_decl_from_type_decl (templ);
5854 pop_decl_namespace ();
5857 context = DECL_CONTEXT (templ);
5859 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1)))
5861 tree type = TREE_TYPE (d1);
5863 /* If we are declaring a constructor, say A<T>::A<T>, we will get
5864 an implicit typename for the second A. Deal with it. */
5865 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
5866 type = TREE_TYPE (type);
5868 if (CLASSTYPE_TEMPLATE_INFO (type))
5870 templ = CLASSTYPE_TI_TEMPLATE (type);
5871 d1 = DECL_NAME (templ);
5874 else if (TREE_CODE (d1) == ENUMERAL_TYPE
5875 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1)))
5877 templ = TYPE_TI_TEMPLATE (d1);
5878 d1 = DECL_NAME (templ);
5880 else if (TREE_CODE (d1) == TEMPLATE_DECL
5881 && DECL_TEMPLATE_RESULT (d1)
5882 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
5885 d1 = DECL_NAME (templ);
5886 context = DECL_CONTEXT (templ);
5889 /* Issue an error message if we didn't find a template. */
5892 if (complain & tf_error)
5893 error ("%qT is not a template", d1);
5894 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5897 if (TREE_CODE (templ) != TEMPLATE_DECL
5898 /* Make sure it's a user visible template, if it was named by
5900 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ)
5901 && !PRIMARY_TEMPLATE_P (templ)))
5903 if (complain & tf_error)
5905 error ("non-template type %qT used as a template", d1);
5907 error ("for template declaration %q+D", in_decl);
5909 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5912 complain &= ~tf_user;
5914 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ))
5916 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
5917 template arguments */
5923 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ);
5925 /* Consider an example where a template template parameter declared as
5927 template <class T, class U = std::allocator<T> > class TT
5929 The template parameter level of T and U are one level larger than
5930 of TT. To proper process the default argument of U, say when an
5931 instantiation `TT<int>' is seen, we need to build the full
5932 arguments containing {int} as the innermost level. Outer levels,
5933 available when not appearing as default template argument, can be
5934 obtained from the arguments of the enclosing template.
5936 Suppose that TT is later substituted with std::vector. The above
5937 instantiation is `TT<int, std::allocator<T> >' with TT at
5938 level 1, and T at level 2, while the template arguments at level 1
5939 becomes {std::vector} and the inner level 2 is {int}. */
5941 outer = DECL_CONTEXT (templ);
5943 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer)));
5944 else if (current_template_parms)
5945 /* This is an argument of the current template, so we haven't set
5946 DECL_CONTEXT yet. */
5947 outer = current_template_args ();
5950 arglist = add_to_template_args (outer, arglist);
5952 arglist2 = coerce_template_parms (parmlist, arglist, templ,
5954 /*require_all_args=*/true,
5955 /*use_default_args=*/true);
5956 if (arglist2 == error_mark_node
5957 || (!uses_template_parms (arglist2)
5958 && check_instantiated_args (templ, arglist2, complain)))
5959 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
5961 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2);
5962 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
5966 tree template_type = TREE_TYPE (templ);
5969 tree found = NULL_TREE;
5972 int is_partial_instantiation;
5974 gen_tmpl = most_general_template (templ);
5975 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
5976 parm_depth = TMPL_PARMS_DEPTH (parmlist);
5977 arg_depth = TMPL_ARGS_DEPTH (arglist);
5979 if (arg_depth == 1 && parm_depth > 1)
5981 /* We've been given an incomplete set of template arguments.
5984 template <class T> struct S1 {
5985 template <class U> struct S2 {};
5986 template <class U> struct S2<U*> {};
5989 we will be called with an ARGLIST of `U*', but the
5990 TEMPLATE will be `template <class T> template
5991 <class U> struct S1<T>::S2'. We must fill in the missing
5994 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)),
5996 arg_depth = TMPL_ARGS_DEPTH (arglist);
5999 /* Now we should have enough arguments. */
6000 gcc_assert (parm_depth == arg_depth);
6002 /* From here on, we're only interested in the most general
6005 /* Calculate the BOUND_ARGS. These will be the args that are
6006 actually tsubst'd into the definition to create the
6010 /* We have multiple levels of arguments to coerce, at once. */
6012 int saved_depth = TMPL_ARGS_DEPTH (arglist);
6014 tree bound_args = make_tree_vec (parm_depth);
6016 for (i = saved_depth,
6017 t = DECL_TEMPLATE_PARMS (gen_tmpl);
6018 i > 0 && t != NULL_TREE;
6019 --i, t = TREE_CHAIN (t))
6021 tree a = coerce_template_parms (TREE_VALUE (t),
6024 /*require_all_args=*/true,
6025 /*use_default_args=*/true);
6027 /* Don't process further if one of the levels fails. */
6028 if (a == error_mark_node)
6030 /* Restore the ARGLIST to its full size. */
6031 TREE_VEC_LENGTH (arglist) = saved_depth;
6032 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6035 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
6037 /* We temporarily reduce the length of the ARGLIST so
6038 that coerce_template_parms will see only the arguments
6039 corresponding to the template parameters it is
6041 TREE_VEC_LENGTH (arglist)--;
6044 /* Restore the ARGLIST to its full size. */
6045 TREE_VEC_LENGTH (arglist) = saved_depth;
6047 arglist = bound_args;
6051 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
6052 INNERMOST_TEMPLATE_ARGS (arglist),
6055 /*require_all_args=*/true,
6056 /*use_default_args=*/true);
6058 if (arglist == error_mark_node)
6059 /* We were unable to bind the arguments. */
6060 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6062 /* In the scope of a template class, explicit references to the
6063 template class refer to the type of the template, not any
6064 instantiation of it. For example, in:
6066 template <class T> class C { void f(C<T>); }
6068 the `C<T>' is just the same as `C'. Outside of the
6069 class, however, such a reference is an instantiation. */
6071 || !PRIMARY_TEMPLATE_P (gen_tmpl)
6072 || currently_open_class (template_type))
6073 /* comp_template_args is expensive, check it last. */
6074 && comp_template_args (TYPE_TI_ARGS (template_type),
6076 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, template_type);
6078 /* If we already have this specialization, return it. */
6079 elt.tmpl = gen_tmpl;
6081 hash = hash_specialization (&elt);
6082 entry = (spec_entry *) htab_find_with_hash (type_specializations,
6086 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, entry->spec);
6088 /* This type is a "partial instantiation" if any of the template
6089 arguments still involve template parameters. Note that we set
6090 IS_PARTIAL_INSTANTIATION for partial specializations as
6092 is_partial_instantiation = uses_template_parms (arglist);
6094 /* If the deduced arguments are invalid, then the binding
6096 if (!is_partial_instantiation
6097 && check_instantiated_args (gen_tmpl,
6098 INNERMOST_TEMPLATE_ARGS (arglist),
6100 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
6102 if (!is_partial_instantiation
6103 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6104 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL)
6106 found = xref_tag_from_type (TREE_TYPE (gen_tmpl),
6107 DECL_NAME (gen_tmpl),
6108 /*tag_scope=*/ts_global);
6109 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
6112 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist,
6115 context = global_namespace;
6117 /* Create the type. */
6118 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
6120 if (!is_partial_instantiation)
6122 set_current_access_from_decl (TYPE_NAME (template_type));
6123 t = start_enum (TYPE_IDENTIFIER (template_type),
6124 tsubst (ENUM_UNDERLYING_TYPE (template_type),
6125 arglist, complain, in_decl),
6126 SCOPED_ENUM_P (template_type));
6130 /* We don't want to call start_enum for this type, since
6131 the values for the enumeration constants may involve
6132 template parameters. And, no one should be interested
6133 in the enumeration constants for such a type. */
6134 t = make_node (ENUMERAL_TYPE);
6135 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type));
6140 t = make_class_type (TREE_CODE (template_type));
6141 CLASSTYPE_DECLARED_CLASS (t)
6142 = CLASSTYPE_DECLARED_CLASS (template_type);
6143 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
6144 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
6146 /* A local class. Make sure the decl gets registered properly. */
6147 if (context == current_function_decl)
6148 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_current);
6150 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist))
6151 /* This instantiation is another name for the primary
6152 template type. Set the TYPE_CANONICAL field
6154 TYPE_CANONICAL (t) = template_type;
6155 else if (any_template_arguments_need_structural_equality_p (arglist))
6156 /* Some of the template arguments require structural
6157 equality testing, so this template class requires
6158 structural equality testing. */
6159 SET_TYPE_STRUCTURAL_EQUALITY (t);
6162 /* If we called start_enum or pushtag above, this information
6163 will already be set up. */
6166 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
6168 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t);
6169 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
6170 TYPE_STUB_DECL (t) = type_decl;
6171 DECL_SOURCE_LOCATION (type_decl)
6172 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
6175 type_decl = TYPE_NAME (t);
6177 TREE_PRIVATE (type_decl)
6178 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
6179 TREE_PROTECTED (type_decl)
6180 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
6181 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
6183 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
6184 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
6187 /* Set up the template information. We have to figure out which
6188 template is the immediate parent if this is a full
6190 if (parm_depth == 1 || is_partial_instantiation
6191 || !PRIMARY_TEMPLATE_P (gen_tmpl))
6192 /* This case is easy; there are no member templates involved. */
6196 /* This is a full instantiation of a member template. Find
6197 the partial instantiation of which this is an instance. */
6199 /* Temporarily reduce by one the number of levels in the ARGLIST
6200 so as to avoid comparing the last set of arguments. */
6201 TREE_VEC_LENGTH (arglist)--;
6202 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE);
6203 TREE_VEC_LENGTH (arglist)++;
6204 found = CLASSTYPE_TI_TEMPLATE (found);
6207 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
6210 slot = (spec_entry **) htab_find_slot_with_hash (type_specializations,
6211 &elt, hash, INSERT);
6212 *slot = GGC_NEW (spec_entry);
6215 /* Note this use of the partial instantiation so we can check it
6216 later in maybe_process_partial_specialization. */
6217 DECL_TEMPLATE_INSTANTIATIONS (templ)
6218 = tree_cons (arglist, t,
6219 DECL_TEMPLATE_INSTANTIATIONS (templ));
6221 if (TREE_CODE (t) == ENUMERAL_TYPE
6222 && !is_partial_instantiation)
6223 /* Now that the type has been registered on the instantiations
6224 list, we set up the enumerators. Because the enumeration
6225 constants may involve the enumeration type itself, we make
6226 sure to register the type first, and then create the
6227 constants. That way, doing tsubst_expr for the enumeration
6228 constants won't result in recursive calls here; we'll find
6229 the instantiation and exit above. */
6230 tsubst_enum (template_type, t, arglist);
6232 if (is_partial_instantiation)
6233 /* If the type makes use of template parameters, the
6234 code that generates debugging information will crash. */
6235 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
6237 /* Possibly limit visibility based on template args. */
6238 TREE_PUBLIC (type_decl) = 1;
6239 determine_visibility (type_decl);
6241 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
6243 timevar_pop (TV_NAME_LOOKUP);
6250 /* True when we should also visit template parameters that occur in
6251 non-deduced contexts. */
6252 bool include_nondeduced_p;
6253 struct pointer_set_t *visited;
6256 /* Called from for_each_template_parm via walk_tree. */
6259 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
6262 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
6263 tree_fn_t fn = pfd->fn;
6264 void *data = pfd->data;
6267 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE)
6268 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited,
6269 pfd->include_nondeduced_p))
6270 return error_mark_node;
6272 switch (TREE_CODE (t))
6275 if (TYPE_PTRMEMFUNC_P (t))
6281 if (!TYPE_TEMPLATE_INFO (t))
6283 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
6284 fn, data, pfd->visited,
6285 pfd->include_nondeduced_p))
6286 return error_mark_node;
6290 if (for_each_template_parm (TYPE_MIN_VALUE (t),
6291 fn, data, pfd->visited,
6292 pfd->include_nondeduced_p)
6293 || for_each_template_parm (TYPE_MAX_VALUE (t),
6294 fn, data, pfd->visited,
6295 pfd->include_nondeduced_p))
6296 return error_mark_node;
6300 /* Since we're not going to walk subtrees, we have to do this
6302 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
6303 pfd->visited, pfd->include_nondeduced_p))
6304 return error_mark_node;
6308 /* Check the return type. */
6309 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6310 pfd->include_nondeduced_p))
6311 return error_mark_node;
6313 /* Check the parameter types. Since default arguments are not
6314 instantiated until they are needed, the TYPE_ARG_TYPES may
6315 contain expressions that involve template parameters. But,
6316 no-one should be looking at them yet. And, once they're
6317 instantiated, they don't contain template parameters, so
6318 there's no point in looking at them then, either. */
6322 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
6323 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
6324 pfd->visited, pfd->include_nondeduced_p))
6325 return error_mark_node;
6327 /* Since we've already handled the TYPE_ARG_TYPES, we don't
6328 want walk_tree walking into them itself. */
6334 if (pfd->include_nondeduced_p
6335 && for_each_template_parm (TYPE_FIELDS (t), fn, data,
6337 pfd->include_nondeduced_p))
6338 return error_mark_node;
6343 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
6344 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
6345 pfd->visited, pfd->include_nondeduced_p))
6346 return error_mark_node;
6351 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
6352 && for_each_template_parm (DECL_INITIAL (t), fn, data,
6353 pfd->visited, pfd->include_nondeduced_p))
6354 return error_mark_node;
6355 if (DECL_CONTEXT (t)
6356 && pfd->include_nondeduced_p
6357 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
6358 pfd->visited, pfd->include_nondeduced_p))
6359 return error_mark_node;
6362 case BOUND_TEMPLATE_TEMPLATE_PARM:
6363 /* Record template parameters such as `T' inside `TT<T>'. */
6364 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited,
6365 pfd->include_nondeduced_p))
6366 return error_mark_node;
6369 case TEMPLATE_TEMPLATE_PARM:
6370 case TEMPLATE_TYPE_PARM:
6371 case TEMPLATE_PARM_INDEX:
6372 if (fn && (*fn)(t, data))
6373 return error_mark_node;
6375 return error_mark_node;
6379 /* A template template parameter is encountered. */
6380 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
6381 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited,
6382 pfd->include_nondeduced_p))
6383 return error_mark_node;
6385 /* Already substituted template template parameter */
6391 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
6393 pfd->include_nondeduced_p))
6394 return error_mark_node;
6398 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
6399 && pfd->include_nondeduced_p
6400 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
6401 (TREE_TYPE (t)), fn, data,
6402 pfd->visited, pfd->include_nondeduced_p))
6403 return error_mark_node;
6408 /* If there's no type, then this thing must be some expression
6409 involving template parameters. */
6410 if (!fn && !TREE_TYPE (t))
6411 return error_mark_node;
6416 case REINTERPRET_CAST_EXPR:
6417 case CONST_CAST_EXPR:
6418 case STATIC_CAST_EXPR:
6419 case DYNAMIC_CAST_EXPR:
6423 case PSEUDO_DTOR_EXPR:
6425 return error_mark_node;
6432 /* We didn't find any template parameters we liked. */
6436 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
6437 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
6438 call FN with the parameter and the DATA.
6439 If FN returns nonzero, the iteration is terminated, and
6440 for_each_template_parm returns 1. Otherwise, the iteration
6441 continues. If FN never returns a nonzero value, the value
6442 returned by for_each_template_parm is 0. If FN is NULL, it is
6443 considered to be the function which always returns 1.
6445 If INCLUDE_NONDEDUCED_P, then this routine will also visit template
6446 parameters that occur in non-deduced contexts. When false, only
6447 visits those template parameters that can be deduced. */
6450 for_each_template_parm (tree t, tree_fn_t fn, void* data,
6451 struct pointer_set_t *visited,
6452 bool include_nondeduced_p)
6454 struct pair_fn_data pfd;
6460 pfd.include_nondeduced_p = include_nondeduced_p;
6462 /* Walk the tree. (Conceptually, we would like to walk without
6463 duplicates, but for_each_template_parm_r recursively calls
6464 for_each_template_parm, so we would need to reorganize a fair
6465 bit to use walk_tree_without_duplicates, so we keep our own
6468 pfd.visited = visited;
6470 pfd.visited = pointer_set_create ();
6471 result = cp_walk_tree (&t,
6472 for_each_template_parm_r,
6474 pfd.visited) != NULL_TREE;
6479 pointer_set_destroy (pfd.visited);
6486 /* Returns true if T depends on any template parameter. */
6489 uses_template_parms (tree t)
6492 int saved_processing_template_decl;
6494 saved_processing_template_decl = processing_template_decl;
6495 if (!saved_processing_template_decl)
6496 processing_template_decl = 1;
6498 dependent_p = dependent_type_p (t);
6499 else if (TREE_CODE (t) == TREE_VEC)
6500 dependent_p = any_dependent_template_arguments_p (t);
6501 else if (TREE_CODE (t) == TREE_LIST)
6502 dependent_p = (uses_template_parms (TREE_VALUE (t))
6503 || uses_template_parms (TREE_CHAIN (t)));
6504 else if (TREE_CODE (t) == TYPE_DECL)
6505 dependent_p = dependent_type_p (TREE_TYPE (t));
6508 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
6509 || TREE_CODE (t) == OVERLOAD
6510 || TREE_CODE (t) == BASELINK
6511 || TREE_CODE (t) == IDENTIFIER_NODE
6512 || TREE_CODE (t) == TRAIT_EXPR
6513 || TREE_CODE (t) == CONSTRUCTOR
6514 || CONSTANT_CLASS_P (t))
6515 dependent_p = (type_dependent_expression_p (t)
6516 || value_dependent_expression_p (t));
6519 gcc_assert (t == error_mark_node);
6520 dependent_p = false;
6523 processing_template_decl = saved_processing_template_decl;
6528 /* Returns true if T depends on any template parameter with level LEVEL. */
6531 uses_template_parms_level (tree t, int level)
6533 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL,
6534 /*include_nondeduced_p=*/true);
6537 static int tinst_depth;
6538 extern int max_tinst_depth;
6539 #ifdef GATHER_STATISTICS
6542 static int tinst_level_tick;
6543 static int last_template_error_tick;
6545 /* We're starting to instantiate D; record the template instantiation context
6546 for diagnostics and to restore it later. */
6549 push_tinst_level (tree d)
6551 struct tinst_level *new_level;
6553 if (tinst_depth >= max_tinst_depth)
6555 /* If the instantiation in question still has unbound template parms,
6556 we don't really care if we can't instantiate it, so just return.
6557 This happens with base instantiation for implicit `typename'. */
6558 if (uses_template_parms (d))
6561 last_template_error_tick = tinst_level_tick;
6562 error ("template instantiation depth exceeds maximum of %d (use "
6563 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
6564 max_tinst_depth, d);
6566 print_instantiation_context ();
6571 new_level = GGC_NEW (struct tinst_level);
6572 new_level->decl = d;
6573 new_level->locus = input_location;
6574 new_level->in_system_header_p = in_system_header;
6575 new_level->next = current_tinst_level;
6576 current_tinst_level = new_level;
6579 #ifdef GATHER_STATISTICS
6580 if (tinst_depth > depth_reached)
6581 depth_reached = tinst_depth;
6588 /* We're done instantiating this template; return to the instantiation
6592 pop_tinst_level (void)
6594 /* Restore the filename and line number stashed away when we started
6595 this instantiation. */
6596 input_location = current_tinst_level->locus;
6597 current_tinst_level = current_tinst_level->next;
6602 /* We're instantiating a deferred template; restore the template
6603 instantiation context in which the instantiation was requested, which
6604 is one step out from LEVEL. Return the corresponding DECL or TYPE. */
6607 reopen_tinst_level (struct tinst_level *level)
6609 struct tinst_level *t;
6612 for (t = level; t; t = t->next)
6615 current_tinst_level = level;
6620 /* Returns the TINST_LEVEL which gives the original instantiation
6623 struct tinst_level *
6624 outermost_tinst_level (void)
6626 struct tinst_level *level = current_tinst_level;
6629 level = level->next;
6633 /* Returns TRUE if PARM is a parameter of the template TEMPL. */
6636 parameter_of_template_p (tree parm, tree templ)
6641 if (!parm || !templ)
6644 gcc_assert (DECL_TEMPLATE_PARM_P (parm));
6645 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
6647 parms = DECL_TEMPLATE_PARMS (templ);
6648 parms = INNERMOST_TEMPLATE_PARMS (parms);
6650 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
6651 if (parm == TREE_VALUE (TREE_VEC_ELT (parms, i)))
6657 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
6658 vector of template arguments, as for tsubst.
6660 Returns an appropriate tsubst'd friend declaration. */
6663 tsubst_friend_function (tree decl, tree args)
6667 if (TREE_CODE (decl) == FUNCTION_DECL
6668 && DECL_TEMPLATE_INSTANTIATION (decl)
6669 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
6670 /* This was a friend declared with an explicit template
6671 argument list, e.g.:
6675 to indicate that f was a template instantiation, not a new
6676 function declaration. Now, we have to figure out what
6677 instantiation of what template. */
6679 tree template_id, arglist, fns;
6682 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
6684 /* Friend functions are looked up in the containing namespace scope.
6685 We must enter that scope, to avoid finding member functions of the
6686 current class with same name. */
6687 push_nested_namespace (ns);
6688 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
6689 tf_warning_or_error, NULL_TREE,
6690 /*integral_constant_expression_p=*/false);
6691 pop_nested_namespace (ns);
6692 arglist = tsubst (DECL_TI_ARGS (decl), args,
6693 tf_warning_or_error, NULL_TREE);
6694 template_id = lookup_template_function (fns, arglist);
6696 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6697 tmpl = determine_specialization (template_id, new_friend,
6699 /*need_member_template=*/0,
6700 TREE_VEC_LENGTH (args),
6702 return instantiate_template (tmpl, new_args, tf_error);
6705 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE);
6707 /* The NEW_FRIEND will look like an instantiation, to the
6708 compiler, but is not an instantiation from the point of view of
6709 the language. For example, we might have had:
6711 template <class T> struct S {
6712 template <class U> friend void f(T, U);
6715 Then, in S<int>, template <class U> void f(int, U) is not an
6716 instantiation of anything. */
6717 if (new_friend == error_mark_node)
6718 return error_mark_node;
6720 DECL_USE_TEMPLATE (new_friend) = 0;
6721 if (TREE_CODE (decl) == TEMPLATE_DECL)
6723 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
6724 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
6725 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
6728 /* The mangled name for the NEW_FRIEND is incorrect. The function
6729 is not a template instantiation and should not be mangled like
6730 one. Therefore, we forget the mangling here; we'll recompute it
6731 later if we need it. */
6732 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
6734 SET_DECL_RTL (new_friend, NULL_RTX);
6735 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
6738 if (DECL_NAMESPACE_SCOPE_P (new_friend))
6741 tree new_friend_template_info;
6742 tree new_friend_result_template_info;
6744 int new_friend_is_defn;
6746 /* We must save some information from NEW_FRIEND before calling
6747 duplicate decls since that function will free NEW_FRIEND if
6749 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
6750 new_friend_is_defn =
6751 (DECL_INITIAL (DECL_TEMPLATE_RESULT
6752 (template_for_substitution (new_friend)))
6754 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
6756 /* This declaration is a `primary' template. */
6757 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
6759 new_friend_result_template_info
6760 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
6763 new_friend_result_template_info = NULL_TREE;
6765 /* Make the init_value nonzero so pushdecl knows this is a defn. */
6766 if (new_friend_is_defn)
6767 DECL_INITIAL (new_friend) = error_mark_node;
6769 /* Inside pushdecl_namespace_level, we will push into the
6770 current namespace. However, the friend function should go
6771 into the namespace of the template. */
6772 ns = decl_namespace_context (new_friend);
6773 push_nested_namespace (ns);
6774 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
6775 pop_nested_namespace (ns);
6777 if (old_decl == error_mark_node)
6778 return error_mark_node;
6780 if (old_decl != new_friend)
6782 /* This new friend declaration matched an existing
6783 declaration. For example, given:
6785 template <class T> void f(T);
6786 template <class U> class C {
6787 template <class T> friend void f(T) {}
6790 the friend declaration actually provides the definition
6791 of `f', once C has been instantiated for some type. So,
6792 old_decl will be the out-of-class template declaration,
6793 while new_friend is the in-class definition.
6795 But, if `f' was called before this point, the
6796 instantiation of `f' will have DECL_TI_ARGS corresponding
6797 to `T' but not to `U', references to which might appear
6798 in the definition of `f'. Previously, the most general
6799 template for an instantiation of `f' was the out-of-class
6800 version; now it is the in-class version. Therefore, we
6801 run through all specialization of `f', adding to their
6802 DECL_TI_ARGS appropriately. In particular, they need a
6803 new set of outer arguments, corresponding to the
6804 arguments for this class instantiation.
6806 The same situation can arise with something like this:
6809 template <class T> class C {
6813 when `C<int>' is instantiated. Now, `f(int)' is defined
6816 if (!new_friend_is_defn)
6817 /* On the other hand, if the in-class declaration does
6818 *not* provide a definition, then we don't want to alter
6819 existing definitions. We can just leave everything
6824 tree new_template = TI_TEMPLATE (new_friend_template_info);
6825 tree new_args = TI_ARGS (new_friend_template_info);
6827 /* Overwrite whatever template info was there before, if
6828 any, with the new template information pertaining to
6830 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
6832 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
6833 /* We should have called reregister_specialization in
6835 gcc_assert (retrieve_specialization (new_template,
6842 /* Indicate that the old function template is a partial
6844 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
6845 = new_friend_result_template_info;
6847 gcc_assert (new_template
6848 == most_general_template (new_template));
6849 gcc_assert (new_template != old_decl);
6851 /* Reassign any specializations already in the hash table
6852 to the new more general template, and add the
6853 additional template args. */
6854 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl);
6858 tree spec = TREE_VALUE (t);
6861 elt.tmpl = old_decl;
6862 elt.args = DECL_TI_ARGS (spec);
6863 elt.spec = NULL_TREE;
6865 htab_remove_elt (decl_specializations, &elt);
6868 = add_outermost_template_args (new_args,
6869 DECL_TI_ARGS (spec));
6871 register_specialization
6872 (spec, new_template, DECL_TI_ARGS (spec), true, 0);
6875 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE;
6879 /* The information from NEW_FRIEND has been merged into OLD_DECL
6880 by duplicate_decls. */
6881 new_friend = old_decl;
6886 tree context = DECL_CONTEXT (new_friend);
6890 template <class T> class C {
6891 template <class U> friend void C1<U>::f (); // case 1
6892 friend void C2<T>::f (); // case 2
6894 we only need to make sure CONTEXT is a complete type for
6895 case 2. To distinguish between the two cases, we note that
6896 CONTEXT of case 1 remains dependent type after tsubst while
6897 this isn't true for case 2. */
6898 ++processing_template_decl;
6899 dependent_p = dependent_type_p (context);
6900 --processing_template_decl;
6903 && !complete_type_or_else (context, NULL_TREE))
6904 return error_mark_node;
6906 if (COMPLETE_TYPE_P (context))
6908 /* Check to see that the declaration is really present, and,
6909 possibly obtain an improved declaration. */
6910 tree fn = check_classfn (context,
6911 new_friend, NULL_TREE);
6921 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
6922 template arguments, as for tsubst.
6924 Returns an appropriate tsubst'd friend type or error_mark_node on
6928 tsubst_friend_class (tree friend_tmpl, tree args)
6934 context = DECL_CONTEXT (friend_tmpl);
6938 if (TREE_CODE (context) == NAMESPACE_DECL)
6939 push_nested_namespace (context);
6941 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
6944 /* Look for a class template declaration. We look for hidden names
6945 because two friend declarations of the same template are the
6946 same. For example, in:
6949 template <typename> friend class F;
6951 template <typename> struct B {
6952 template <typename> friend class F;
6955 both F templates are the same. */
6956 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0,
6957 /*block_p=*/true, 0,
6958 LOOKUP_COMPLAIN | LOOKUP_HIDDEN);
6960 /* But, if we don't find one, it might be because we're in a
6961 situation like this:
6969 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
6970 for `S<int>', not the TEMPLATE_DECL. */
6971 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
6973 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1);
6974 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
6977 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
6979 /* The friend template has already been declared. Just
6980 check to see that the declarations match, and install any new
6981 default parameters. We must tsubst the default parameters,
6982 of course. We only need the innermost template parameters
6983 because that is all that redeclare_class_template will look
6985 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
6986 > TMPL_ARGS_DEPTH (args))
6989 location_t saved_input_location;
6990 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
6991 args, tf_warning_or_error);
6993 saved_input_location = input_location;
6994 input_location = DECL_SOURCE_LOCATION (friend_tmpl);
6995 redeclare_class_template (TREE_TYPE (tmpl), parms);
6996 input_location = saved_input_location;
7000 friend_type = TREE_TYPE (tmpl);
7004 /* The friend template has not already been declared. In this
7005 case, the instantiation of the template class will cause the
7006 injection of this template into the global scope. */
7007 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE);
7008 if (tmpl == error_mark_node)
7009 return error_mark_node;
7011 /* The new TMPL is not an instantiation of anything, so we
7012 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
7013 the new type because that is supposed to be the corresponding
7014 template decl, i.e., TMPL. */
7015 DECL_USE_TEMPLATE (tmpl) = 0;
7016 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
7017 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
7018 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
7019 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
7021 /* Inject this template into the global scope. */
7022 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
7027 if (TREE_CODE (context) == NAMESPACE_DECL)
7028 pop_nested_namespace (context);
7030 pop_nested_class ();
7036 /* Returns zero if TYPE cannot be completed later due to circularity.
7037 Otherwise returns one. */
7040 can_complete_type_without_circularity (tree type)
7042 if (type == NULL_TREE || type == error_mark_node)
7044 else if (COMPLETE_TYPE_P (type))
7046 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
7047 return can_complete_type_without_circularity (TREE_TYPE (type));
7048 else if (CLASS_TYPE_P (type)
7049 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
7055 /* Apply any attributes which had to be deferred until instantiation
7056 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes;
7057 ARGS, COMPLAIN, IN_DECL are as tsubst. */
7060 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags,
7061 tree args, tsubst_flags_t complain, tree in_decl)
7063 tree last_dep = NULL_TREE;
7067 for (t = attributes; t; t = TREE_CHAIN (t))
7068 if (ATTR_IS_DEPENDENT (t))
7071 attributes = copy_list (attributes);
7075 if (DECL_P (*decl_p))
7077 if (TREE_TYPE (*decl_p) == error_mark_node)
7079 p = &DECL_ATTRIBUTES (*decl_p);
7082 p = &TYPE_ATTRIBUTES (*decl_p);
7086 tree late_attrs = NULL_TREE;
7087 tree *q = &late_attrs;
7089 for (*p = attributes; *p; )
7092 if (ATTR_IS_DEPENDENT (t))
7094 *p = TREE_CHAIN (t);
7095 TREE_CHAIN (t) = NULL_TREE;
7096 /* If the first attribute argument is an identifier, don't
7097 pass it through tsubst. Attributes like mode, format,
7098 cleanup and several target specific attributes expect it
7101 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST
7102 && TREE_VALUE (TREE_VALUE (t))
7103 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t)))
7104 == IDENTIFIER_NODE))
7107 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain,
7109 /*integral_constant_expression_p=*/false);
7110 if (chain != TREE_CHAIN (TREE_VALUE (t)))
7112 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)),
7117 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl,
7118 /*integral_constant_expression_p=*/false);
7120 q = &TREE_CHAIN (t);
7123 p = &TREE_CHAIN (t);
7126 cplus_decl_attributes (decl_p, late_attrs, attr_flags);
7130 /* Perform (or defer) access check for typedefs that were referenced
7131 from within the template TMPL code.
7132 This is a subroutine of instantiate_template and instantiate_class_template.
7133 TMPL is the template to consider and TARGS is the list of arguments of
7137 perform_typedefs_access_check (tree tmpl, tree targs)
7142 || (TREE_CODE (tmpl) != RECORD_TYPE
7143 && TREE_CODE (tmpl) != FUNCTION_DECL))
7146 for (t = get_types_needing_access_check (tmpl); t; t = TREE_CHAIN (t))
7148 tree type_decl = TREE_PURPOSE (t);
7149 tree type_scope = TREE_VALUE (t);
7151 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope))
7154 if (uses_template_parms (type_decl))
7155 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE);
7156 if (uses_template_parms (type_scope))
7157 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE);
7159 perform_or_defer_access_check (TYPE_BINFO (type_scope),
7160 type_decl, type_decl);
7165 instantiate_class_template (tree type)
7167 tree templ, args, pattern, t, member;
7172 if (type == error_mark_node)
7173 return error_mark_node;
7175 if (TYPE_BEING_DEFINED (type)
7176 || COMPLETE_TYPE_P (type)
7177 || dependent_type_p (type))
7180 /* Figure out which template is being instantiated. */
7181 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
7182 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL);
7184 /* Determine what specialization of the original template to
7186 t = most_specialized_class (type, templ);
7187 if (t == error_mark_node)
7189 TYPE_BEING_DEFINED (type) = 1;
7190 return error_mark_node;
7194 /* This TYPE is actually an instantiation of a partial
7195 specialization. We replace the innermost set of ARGS with
7196 the arguments appropriate for substitution. For example,
7199 template <class T> struct S {};
7200 template <class T> struct S<T*> {};
7202 and supposing that we are instantiating S<int*>, ARGS will
7203 presently be {int*} -- but we need {int}. */
7204 pattern = TREE_TYPE (t);
7205 args = TREE_PURPOSE (t);
7209 pattern = TREE_TYPE (templ);
7210 args = CLASSTYPE_TI_ARGS (type);
7213 /* If the template we're instantiating is incomplete, then clearly
7214 there's nothing we can do. */
7215 if (!COMPLETE_TYPE_P (pattern))
7218 /* If we've recursively instantiated too many templates, stop. */
7219 if (! push_tinst_level (type))
7222 /* Now we're really doing the instantiation. Mark the type as in
7223 the process of being defined. */
7224 TYPE_BEING_DEFINED (type) = 1;
7226 /* We may be in the middle of deferred access check. Disable
7228 push_deferring_access_checks (dk_no_deferred);
7230 push_to_top_level ();
7232 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
7234 /* Set the input location to the most specialized template definition.
7235 This is needed if tsubsting causes an error. */
7236 typedecl = TYPE_MAIN_DECL (pattern);
7237 input_location = DECL_SOURCE_LOCATION (typedecl);
7239 TYPE_HAS_USER_CONSTRUCTOR (type) = TYPE_HAS_USER_CONSTRUCTOR (pattern);
7240 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
7241 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
7242 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
7243 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
7244 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
7245 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
7246 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
7247 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
7248 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
7249 TYPE_PACKED (type) = TYPE_PACKED (pattern);
7250 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
7251 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
7252 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
7253 if (ANON_AGGR_TYPE_P (pattern))
7254 SET_ANON_AGGR_TYPE_P (type);
7255 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
7257 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
7258 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
7261 pbinfo = TYPE_BINFO (pattern);
7263 /* We should never instantiate a nested class before its enclosing
7264 class; we need to look up the nested class by name before we can
7265 instantiate it, and that lookup should instantiate the enclosing
7267 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
7268 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
7269 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
7271 base_list = NULL_TREE;
7272 if (BINFO_N_BASE_BINFOS (pbinfo))
7275 tree context = TYPE_CONTEXT (type);
7279 /* We must enter the scope containing the type, as that is where
7280 the accessibility of types named in dependent bases are
7282 pushed_scope = push_scope (context ? context : global_namespace);
7284 /* Substitute into each of the bases to determine the actual
7286 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
7289 tree access = BINFO_BASE_ACCESS (pbinfo, i);
7290 tree expanded_bases = NULL_TREE;
7293 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo)))
7296 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo),
7297 args, tf_error, NULL_TREE);
7298 if (expanded_bases == error_mark_node)
7301 len = TREE_VEC_LENGTH (expanded_bases);
7304 for (idx = 0; idx < len; idx++)
7307 /* Extract the already-expanded base class. */
7308 base = TREE_VEC_ELT (expanded_bases, idx);
7310 /* Substitute to figure out the base class. */
7311 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error,
7314 if (base == error_mark_node)
7317 base_list = tree_cons (access, base, base_list);
7318 if (BINFO_VIRTUAL_P (pbase_binfo))
7319 TREE_TYPE (base_list) = integer_type_node;
7323 /* The list is now in reverse order; correct that. */
7324 base_list = nreverse (base_list);
7327 pop_scope (pushed_scope);
7329 /* Now call xref_basetypes to set up all the base-class
7331 xref_basetypes (type, base_list);
7333 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern),
7334 (int) ATTR_FLAG_TYPE_IN_PLACE,
7335 args, tf_error, NULL_TREE);
7337 /* Now that our base classes are set up, enter the scope of the
7338 class, so that name lookups into base classes, etc. will work
7339 correctly. This is precisely analogous to what we do in
7340 begin_class_definition when defining an ordinary non-template
7341 class, except we also need to push the enclosing classes. */
7342 push_nested_class (type);
7344 /* Now members are processed in the order of declaration. */
7345 for (member = CLASSTYPE_DECL_LIST (pattern);
7346 member; member = TREE_CHAIN (member))
7348 tree t = TREE_VALUE (member);
7350 if (TREE_PURPOSE (member))
7354 /* Build new CLASSTYPE_NESTED_UTDS. */
7357 bool class_template_p;
7359 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE
7360 && TYPE_LANG_SPECIFIC (t)
7361 && CLASSTYPE_IS_TEMPLATE (t));
7362 /* If the member is a class template, then -- even after
7363 substitution -- there may be dependent types in the
7364 template argument list for the class. We increment
7365 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
7366 that function will assume that no types are dependent
7367 when outside of a template. */
7368 if (class_template_p)
7369 ++processing_template_decl;
7370 newtag = tsubst (t, args, tf_error, NULL_TREE);
7371 if (class_template_p)
7372 --processing_template_decl;
7373 if (newtag == error_mark_node)
7376 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
7378 tree name = TYPE_IDENTIFIER (t);
7380 if (class_template_p)
7381 /* Unfortunately, lookup_template_class sets
7382 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
7383 instantiation (i.e., for the type of a member
7384 template class nested within a template class.)
7385 This behavior is required for
7386 maybe_process_partial_specialization to work
7387 correctly, but is not accurate in this case;
7388 the TAG is not an instantiation of anything.
7389 (The corresponding TEMPLATE_DECL is an
7390 instantiation, but the TYPE is not.) */
7391 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
7393 /* Now, we call pushtag to put this NEWTAG into the scope of
7394 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
7395 pushtag calling push_template_decl. We don't have to do
7396 this for enums because it will already have been done in
7399 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
7400 pushtag (name, newtag, /*tag_scope=*/ts_current);
7403 else if (TREE_CODE (t) == FUNCTION_DECL
7404 || DECL_FUNCTION_TEMPLATE_P (t))
7406 /* Build new TYPE_METHODS. */
7409 if (TREE_CODE (t) == TEMPLATE_DECL)
7410 ++processing_template_decl;
7411 r = tsubst (t, args, tf_error, NULL_TREE);
7412 if (TREE_CODE (t) == TEMPLATE_DECL)
7413 --processing_template_decl;
7414 set_current_access_from_decl (r);
7415 finish_member_declaration (r);
7419 /* Build new TYPE_FIELDS. */
7420 if (TREE_CODE (t) == STATIC_ASSERT)
7423 tsubst_expr (STATIC_ASSERT_CONDITION (t), args,
7424 tf_warning_or_error, NULL_TREE,
7425 /*integral_constant_expression_p=*/true);
7426 finish_static_assert (condition,
7427 STATIC_ASSERT_MESSAGE (t),
7428 STATIC_ASSERT_SOURCE_LOCATION (t),
7431 else if (TREE_CODE (t) != CONST_DECL)
7435 /* The file and line for this declaration, to
7436 assist in error message reporting. Since we
7437 called push_tinst_level above, we don't need to
7439 input_location = DECL_SOURCE_LOCATION (t);
7441 if (TREE_CODE (t) == TEMPLATE_DECL)
7442 ++processing_template_decl;
7443 r = tsubst (t, args, tf_warning_or_error, NULL_TREE);
7444 if (TREE_CODE (t) == TEMPLATE_DECL)
7445 --processing_template_decl;
7446 if (TREE_CODE (r) == VAR_DECL)
7450 [t]he initialization (and any associated
7451 side-effects) of a static data member does
7452 not occur unless the static data member is
7453 itself used in a way that requires the
7454 definition of the static data member to
7457 Therefore, we do not substitute into the
7458 initialized for the static data member here. */
7459 finish_static_data_member_decl
7462 /*init_const_expr_p=*/false,
7463 /*asmspec_tree=*/NULL_TREE,
7465 if (DECL_INITIALIZED_IN_CLASS_P (r))
7466 check_static_variable_definition (r, TREE_TYPE (r));
7468 else if (TREE_CODE (r) == FIELD_DECL)
7470 /* Determine whether R has a valid type and can be
7471 completed later. If R is invalid, then it is
7472 replaced by error_mark_node so that it will not be
7473 added to TYPE_FIELDS. */
7474 tree rtype = TREE_TYPE (r);
7475 if (can_complete_type_without_circularity (rtype))
7476 complete_type (rtype);
7478 if (!COMPLETE_TYPE_P (rtype))
7480 cxx_incomplete_type_error (r, rtype);
7481 r = error_mark_node;
7485 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
7486 such a thing will already have been added to the field
7487 list by tsubst_enum in finish_member_declaration in the
7488 CLASSTYPE_NESTED_UTDS case above. */
7489 if (!(TREE_CODE (r) == TYPE_DECL
7490 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
7491 && DECL_ARTIFICIAL (r)))
7493 set_current_access_from_decl (r);
7494 finish_member_declaration (r);
7501 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
7503 /* Build new CLASSTYPE_FRIEND_CLASSES. */
7505 tree friend_type = t;
7506 bool adjust_processing_template_decl = false;
7508 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7510 /* template <class T> friend class C; */
7511 friend_type = tsubst_friend_class (friend_type, args);
7512 adjust_processing_template_decl = true;
7514 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
7516 /* template <class T> friend class C::D; */
7517 friend_type = tsubst (friend_type, args,
7518 tf_warning_or_error, NULL_TREE);
7519 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
7520 friend_type = TREE_TYPE (friend_type);
7521 adjust_processing_template_decl = true;
7523 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
7525 /* This could be either
7529 when dependent_type_p is false or
7531 template <class U> friend class T::C;
7534 friend_type = tsubst (friend_type, args,
7535 tf_warning_or_error, NULL_TREE);
7536 /* Bump processing_template_decl for correct
7537 dependent_type_p calculation. */
7538 ++processing_template_decl;
7539 if (dependent_type_p (friend_type))
7540 adjust_processing_template_decl = true;
7541 --processing_template_decl;
7543 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
7544 && hidden_name_p (TYPE_NAME (friend_type)))
7548 where C hasn't been declared yet. Let's lookup name
7549 from namespace scope directly, bypassing any name that
7550 come from dependent base class. */
7551 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
7553 /* The call to xref_tag_from_type does injection for friend
7555 push_nested_namespace (ns);
7557 xref_tag_from_type (friend_type, NULL_TREE,
7558 /*tag_scope=*/ts_current);
7559 pop_nested_namespace (ns);
7561 else if (uses_template_parms (friend_type))
7562 /* friend class C<T>; */
7563 friend_type = tsubst (friend_type, args,
7564 tf_warning_or_error, NULL_TREE);
7569 where C is already declared or
7571 friend class C<int>;
7573 We don't have to do anything in these cases. */
7575 if (adjust_processing_template_decl)
7576 /* Trick make_friend_class into realizing that the friend
7577 we're adding is a template, not an ordinary class. It's
7578 important that we use make_friend_class since it will
7579 perform some error-checking and output cross-reference
7581 ++processing_template_decl;
7583 if (friend_type != error_mark_node)
7584 make_friend_class (type, friend_type, /*complain=*/false);
7586 if (adjust_processing_template_decl)
7587 --processing_template_decl;
7591 /* Build new DECL_FRIENDLIST. */
7594 /* The file and line for this declaration, to
7595 assist in error message reporting. Since we
7596 called push_tinst_level above, we don't need to
7598 input_location = DECL_SOURCE_LOCATION (t);
7600 if (TREE_CODE (t) == TEMPLATE_DECL)
7602 ++processing_template_decl;
7603 push_deferring_access_checks (dk_no_check);
7606 r = tsubst_friend_function (t, args);
7607 add_friend (type, r, /*complain=*/false);
7608 if (TREE_CODE (t) == TEMPLATE_DECL)
7610 pop_deferring_access_checks ();
7611 --processing_template_decl;
7617 /* Set the file and line number information to whatever is given for
7618 the class itself. This puts error messages involving generated
7619 implicit functions at a predictable point, and the same point
7620 that would be used for non-template classes. */
7621 input_location = DECL_SOURCE_LOCATION (typedecl);
7623 unreverse_member_declarations (type);
7624 finish_struct_1 (type);
7625 TYPE_BEING_DEFINED (type) = 0;
7627 /* Now that the class is complete, instantiate default arguments for
7628 any member functions. We don't do this earlier because the
7629 default arguments may reference members of the class. */
7630 if (!PRIMARY_TEMPLATE_P (templ))
7631 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
7632 if (TREE_CODE (t) == FUNCTION_DECL
7633 /* Implicitly generated member functions will not have template
7634 information; they are not instantiations, but instead are
7635 created "fresh" for each instantiation. */
7636 && DECL_TEMPLATE_INFO (t))
7637 tsubst_default_arguments (t);
7639 /* Some typedefs referenced from within the template code need to be access
7640 checked at template instantiation time, i.e now. These types were
7641 added to the template at parsing time. Let's get those and perform
7642 the access checks then. */
7643 perform_typedefs_access_check (pattern, args);
7644 perform_deferred_access_checks ();
7645 pop_nested_class ();
7646 pop_from_top_level ();
7647 pop_deferring_access_checks ();
7650 /* The vtable for a template class can be emitted in any translation
7651 unit in which the class is instantiated. When there is no key
7652 method, however, finish_struct_1 will already have added TYPE to
7653 the keyed_classes list. */
7654 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
7655 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
7661 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7667 else if (TYPE_P (t))
7668 r = tsubst (t, args, complain, in_decl);
7671 r = tsubst_expr (t, args, complain, in_decl,
7672 /*integral_constant_expression_p=*/true);
7673 r = fold_non_dependent_expr (r);
7678 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a
7679 NONTYPE_ARGUMENT_PACK. */
7682 make_fnparm_pack (tree spec_parm)
7684 /* Collect all of the extra "packed" parameters into an
7688 tree argpack = make_node (NONTYPE_ARGUMENT_PACK);
7689 tree argtypepack = make_node (TYPE_ARGUMENT_PACK);
7690 int i, len = list_length (spec_parm);
7692 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */
7693 parmvec = make_tree_vec (len);
7694 parmtypevec = make_tree_vec (len);
7695 for (i = 0; i < len; i++, spec_parm = TREE_CHAIN (spec_parm))
7697 TREE_VEC_ELT (parmvec, i) = spec_parm;
7698 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm);
7701 /* Build the argument packs. */
7702 SET_ARGUMENT_PACK_ARGS (argpack, parmvec);
7703 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec);
7704 TREE_TYPE (argpack) = argtypepack;
7709 /* Substitute ARGS into T, which is an pack expansion
7710 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a
7711 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node
7712 (if only a partial substitution could be performed) or
7713 ERROR_MARK_NODE if there was an error. */
7715 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain,
7719 tree pack, packs = NULL_TREE, unsubstituted_packs = NULL_TREE;
7720 tree first_arg_pack; int i, len = -1;
7723 bool very_local_specializations = false;
7725 gcc_assert (PACK_EXPANSION_P (t));
7726 pattern = PACK_EXPANSION_PATTERN (t);
7728 /* Determine the argument packs that will instantiate the parameter
7729 packs used in the expansion expression. While we're at it,
7730 compute the number of arguments to be expanded and make sure it
7732 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack;
7733 pack = TREE_CHAIN (pack))
7735 tree parm_pack = TREE_VALUE (pack);
7736 tree arg_pack = NULL_TREE;
7737 tree orig_arg = NULL_TREE;
7739 if (TREE_CODE (parm_pack) == PARM_DECL)
7741 arg_pack = retrieve_local_specialization (parm_pack);
7742 if (arg_pack == NULL_TREE)
7744 /* This can happen for a parameter name used later in a function
7745 declaration (such as in a late-specified return type). Just
7746 make a dummy decl, since it's only used for its type. */
7747 gcc_assert (cp_unevaluated_operand != 0);
7748 arg_pack = tsubst_decl (parm_pack, args, complain);
7749 arg_pack = make_fnparm_pack (arg_pack);
7754 int level, idx, levels;
7755 template_parm_level_and_index (parm_pack, &level, &idx);
7757 levels = TMPL_ARGS_DEPTH (args);
7758 if (level <= levels)
7759 arg_pack = TMPL_ARG (args, level, idx);
7762 orig_arg = arg_pack;
7763 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT)
7764 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack);
7766 if (arg_pack && !ARGUMENT_PACK_P (arg_pack))
7767 /* This can only happen if we forget to expand an argument
7768 pack somewhere else. Just return an error, silently. */
7770 result = make_tree_vec (1);
7771 TREE_VEC_ELT (result, 0) = error_mark_node;
7776 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1
7777 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0)))
7779 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0);
7780 tree pattern = PACK_EXPANSION_PATTERN (expansion);
7781 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack))
7782 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern)))
7783 /* The argument pack that the parameter maps to is just an
7784 expansion of the parameter itself, such as one would
7785 find in the implicit typedef of a class inside the
7786 class itself. Consider this parameter "unsubstituted",
7787 so that we will maintain the outer pack expansion. */
7788 arg_pack = NULL_TREE;
7794 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack));
7796 /* It's all-or-nothing with incomplete argument packs. */
7797 if (incomplete && !ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7798 return error_mark_node;
7800 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack))
7806 first_arg_pack = arg_pack;
7808 else if (len != my_len)
7810 if (TREE_CODE (t) == TYPE_PACK_EXPANSION)
7811 error ("mismatched argument pack lengths while expanding "
7815 error ("mismatched argument pack lengths while expanding "
7818 return error_mark_node;
7821 /* Keep track of the parameter packs and their corresponding
7823 packs = tree_cons (parm_pack, arg_pack, packs);
7824 TREE_TYPE (packs) = orig_arg;
7827 /* We can't substitute for this parameter pack. */
7828 unsubstituted_packs = tree_cons (TREE_PURPOSE (pack),
7830 unsubstituted_packs);
7833 /* We cannot expand this expansion expression, because we don't have
7834 all of the argument packs we need. Substitute into the pattern
7835 and return a PACK_EXPANSION_*. The caller will need to deal with
7837 if (unsubstituted_packs)
7840 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
7841 new_pat = tsubst_expr (pattern, args, complain, in_decl,
7842 /*integral_constant_expression_p=*/false);
7844 new_pat = tsubst (pattern, args, complain, in_decl);
7845 return make_pack_expansion (new_pat);
7848 /* We could not find any argument packs that work. */
7850 return error_mark_node;
7852 if (!local_specializations)
7854 /* We're in a late-specified return type, so we don't have a local
7855 specializations table. Create one for doing this expansion. */
7856 very_local_specializations = true;
7857 local_specializations = htab_create (37,
7858 hash_local_specialization,
7859 eq_local_specializations,
7863 /* For each argument in each argument pack, substitute into the
7865 result = make_tree_vec (len + incomplete);
7866 for (i = 0; i < len + incomplete; ++i)
7868 /* For parameter pack, change the substitution of the parameter
7869 pack to the ith argument in its argument pack, then expand
7871 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7873 tree parm = TREE_PURPOSE (pack);
7875 if (TREE_CODE (parm) == PARM_DECL)
7877 /* Select the Ith argument from the pack. */
7878 tree arg = make_node (ARGUMENT_PACK_SELECT);
7879 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack);
7880 ARGUMENT_PACK_SELECT_INDEX (arg) = i;
7882 register_local_specialization (arg, parm);
7888 template_parm_level_and_index (parm, &level, &idx);
7892 /* Select the Ith argument from the pack. */
7893 value = make_node (ARGUMENT_PACK_SELECT);
7894 ARGUMENT_PACK_SELECT_FROM_PACK (value) = TREE_VALUE (pack);
7895 ARGUMENT_PACK_SELECT_INDEX (value) = i;
7898 /* Update the corresponding argument. */
7899 TMPL_ARG (args, level, idx) = value;
7903 /* Substitute into the PATTERN with the altered arguments. */
7904 if (TREE_CODE (t) == EXPR_PACK_EXPANSION)
7905 TREE_VEC_ELT (result, i) =
7906 tsubst_expr (pattern, args, complain, in_decl,
7907 /*integral_constant_expression_p=*/false);
7909 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl);
7912 /* When we have incomplete argument packs, the last "expanded"
7913 result is itself a pack expansion, which allows us
7914 to deduce more arguments. */
7915 TREE_VEC_ELT (result, i) =
7916 make_pack_expansion (TREE_VEC_ELT (result, i));
7918 if (TREE_VEC_ELT (result, i) == error_mark_node)
7920 result = error_mark_node;
7925 /* Update ARGS to restore the substitution from parameter packs to
7926 their argument packs. */
7927 for (pack = packs; pack; pack = TREE_CHAIN (pack))
7929 tree parm = TREE_PURPOSE (pack);
7931 if (TREE_CODE (parm) == PARM_DECL)
7932 register_local_specialization (TREE_TYPE (pack), parm);
7936 template_parm_level_and_index (parm, &level, &idx);
7938 /* Update the corresponding argument. */
7939 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
7940 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) =
7943 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack);
7947 if (very_local_specializations)
7949 htab_delete (local_specializations);
7950 local_specializations = NULL;
7956 /* Substitute ARGS into the vector or list of template arguments T. */
7959 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7962 int len = TREE_VEC_LENGTH (t);
7963 int need_new = 0, i, expanded_len_adjust = 0, out;
7964 tree *elts = (tree *) alloca (len * sizeof (tree));
7966 for (i = 0; i < len; i++)
7968 tree orig_arg = TREE_VEC_ELT (t, i);
7971 if (TREE_CODE (orig_arg) == TREE_VEC)
7972 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
7973 else if (PACK_EXPANSION_P (orig_arg))
7975 /* Substitute into an expansion expression. */
7976 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl);
7978 if (TREE_CODE (new_arg) == TREE_VEC)
7979 /* Add to the expanded length adjustment the number of
7980 expanded arguments. We subtract one from this
7981 measurement, because the argument pack expression
7982 itself is already counted as 1 in
7983 LEN. EXPANDED_LEN_ADJUST can actually be negative, if
7984 the argument pack is empty. */
7985 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1;
7987 else if (ARGUMENT_PACK_P (orig_arg))
7989 /* Substitute into each of the arguments. */
7990 new_arg = make_node (TREE_CODE (orig_arg));
7992 SET_ARGUMENT_PACK_ARGS (
7994 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg),
7995 args, complain, in_decl));
7997 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node)
7998 new_arg = error_mark_node;
8000 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) {
8001 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args,
8003 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg);
8005 if (TREE_TYPE (new_arg) == error_mark_node)
8006 new_arg = error_mark_node;
8010 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
8012 if (new_arg == error_mark_node)
8013 return error_mark_node;
8016 if (new_arg != orig_arg)
8023 /* Make space for the expanded arguments coming from template
8025 t = make_tree_vec (len + expanded_len_adjust);
8026 for (i = 0, out = 0; i < len; i++)
8028 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i))
8029 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i)))
8030 && TREE_CODE (elts[i]) == TREE_VEC)
8034 /* Now expand the template argument pack "in place". */
8035 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++)
8036 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx);
8040 TREE_VEC_ELT (t, out) = elts[i];
8048 /* Return the result of substituting ARGS into the template parameters
8049 given by PARMS. If there are m levels of ARGS and m + n levels of
8050 PARMS, then the result will contain n levels of PARMS. For
8051 example, if PARMS is `template <class T> template <class U>
8052 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
8053 result will be `template <int*, double, class V>'. */
8056 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
8061 /* When substituting into a template, we must set
8062 PROCESSING_TEMPLATE_DECL as the template parameters may be
8063 dependent if they are based on one-another, and the dependency
8064 predicates are short-circuit outside of templates. */
8065 ++processing_template_decl;
8067 for (new_parms = &r;
8068 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
8069 new_parms = &(TREE_CHAIN (*new_parms)),
8070 parms = TREE_CHAIN (parms))
8073 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
8076 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
8082 if (parms == error_mark_node)
8085 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
8087 if (tuple == error_mark_node)
8090 default_value = TREE_PURPOSE (tuple);
8091 parm_decl = TREE_VALUE (tuple);
8093 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
8094 if (TREE_CODE (parm_decl) == PARM_DECL
8095 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
8096 parm_decl = error_mark_node;
8097 default_value = tsubst_template_arg (default_value, args,
8098 complain, NULL_TREE);
8100 tuple = build_tree_list (default_value, parm_decl);
8101 TREE_VEC_ELT (new_vec, i) = tuple;
8105 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
8106 - TMPL_ARGS_DEPTH (args)),
8107 new_vec, NULL_TREE);
8110 --processing_template_decl;
8115 /* Substitute the ARGS into the indicated aggregate (or enumeration)
8116 type T. If T is not an aggregate or enumeration type, it is
8117 handled as if by tsubst. IN_DECL is as for tsubst. If
8118 ENTERING_SCOPE is nonzero, T is the context for a template which
8119 we are presently tsubst'ing. Return the substituted value. */
8122 tsubst_aggr_type (tree t,
8124 tsubst_flags_t complain,
8131 switch (TREE_CODE (t))
8134 if (TYPE_PTRMEMFUNC_P (t))
8135 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
8137 /* Else fall through. */
8140 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t))
8145 int saved_unevaluated_operand;
8146 int saved_inhibit_evaluation_warnings;
8148 /* In "sizeof(X<I>)" we need to evaluate "I". */
8149 saved_unevaluated_operand = cp_unevaluated_operand;
8150 cp_unevaluated_operand = 0;
8151 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings;
8152 c_inhibit_evaluation_warnings = 0;
8154 /* First, determine the context for the type we are looking
8156 context = TYPE_CONTEXT (t);
8159 context = tsubst_aggr_type (context, args, complain,
8160 in_decl, /*entering_scope=*/1);
8161 /* If context is a nested class inside a class template,
8162 it may still need to be instantiated (c++/33959). */
8163 if (TYPE_P (context))
8164 context = complete_type (context);
8167 /* Then, figure out what arguments are appropriate for the
8168 type we are trying to find. For example, given:
8170 template <class T> struct S;
8171 template <class T, class U> void f(T, U) { S<U> su; }
8173 and supposing that we are instantiating f<int, double>,
8174 then our ARGS will be {int, double}, but, when looking up
8175 S we only want {double}. */
8176 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
8178 if (argvec == error_mark_node)
8179 r = error_mark_node;
8182 r = lookup_template_class (t, argvec, in_decl, context,
8183 entering_scope, complain);
8184 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
8187 cp_unevaluated_operand = saved_unevaluated_operand;
8188 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings;
8193 /* This is not a template type, so there's nothing to do. */
8197 return tsubst (t, args, complain, in_decl);
8201 /* Substitute into the default argument ARG (a default argument for
8202 FN), which has the indicated TYPE. */
8205 tsubst_default_argument (tree fn, tree type, tree arg)
8207 tree saved_class_ptr = NULL_TREE;
8208 tree saved_class_ref = NULL_TREE;
8210 /* This default argument came from a template. Instantiate the
8211 default argument here, not in tsubst. In the case of
8220 we must be careful to do name lookup in the scope of S<T>,
8221 rather than in the current class. */
8222 push_access_scope (fn);
8223 /* The "this" pointer is not valid in a default argument. */
8226 saved_class_ptr = current_class_ptr;
8227 cp_function_chain->x_current_class_ptr = NULL_TREE;
8228 saved_class_ref = current_class_ref;
8229 cp_function_chain->x_current_class_ref = NULL_TREE;
8232 push_deferring_access_checks(dk_no_deferred);
8233 /* The default argument expression may cause implicitly defined
8234 member functions to be synthesized, which will result in garbage
8235 collection. We must treat this situation as if we were within
8236 the body of function so as to avoid collecting live data on the
8239 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
8240 tf_warning_or_error, NULL_TREE,
8241 /*integral_constant_expression_p=*/false);
8243 pop_deferring_access_checks();
8245 /* Restore the "this" pointer. */
8248 cp_function_chain->x_current_class_ptr = saved_class_ptr;
8249 cp_function_chain->x_current_class_ref = saved_class_ref;
8252 pop_access_scope (fn);
8254 /* Make sure the default argument is reasonable. */
8255 arg = check_default_argument (type, arg);
8260 /* Substitute into all the default arguments for FN. */
8263 tsubst_default_arguments (tree fn)
8268 tmpl_args = DECL_TI_ARGS (fn);
8270 /* If this function is not yet instantiated, we certainly don't need
8271 its default arguments. */
8272 if (uses_template_parms (tmpl_args))
8275 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
8277 arg = TREE_CHAIN (arg))
8278 if (TREE_PURPOSE (arg))
8279 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
8281 TREE_PURPOSE (arg));
8284 /* Substitute the ARGS into the T, which is a _DECL. Return the
8285 result of the substitution. Issue error and warning messages under
8286 control of COMPLAIN. */
8289 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
8291 location_t saved_loc;
8296 /* Set the filename and linenumber to improve error-reporting. */
8297 saved_loc = input_location;
8298 input_location = DECL_SOURCE_LOCATION (t);
8300 switch (TREE_CODE (t))
8304 /* We can get here when processing a member function template,
8305 member class template, and template template parameter of
8306 a template class. */
8307 tree decl = DECL_TEMPLATE_RESULT (t);
8312 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
8314 /* Template template parameter is treated here. */
8315 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8316 if (new_type == error_mark_node)
8317 return error_mark_node;
8320 TREE_CHAIN (r) = NULL_TREE;
8321 TREE_TYPE (r) = new_type;
8322 DECL_TEMPLATE_RESULT (r)
8323 = build_decl (DECL_SOURCE_LOCATION (decl),
8324 TYPE_DECL, DECL_NAME (decl), new_type);
8325 DECL_TEMPLATE_PARMS (r)
8326 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8328 TYPE_NAME (new_type) = r;
8332 /* We might already have an instance of this template.
8333 The ARGS are for the surrounding class type, so the
8334 full args contain the tsubst'd args for the context,
8335 plus the innermost args from the template decl. */
8336 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
8337 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
8338 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
8339 /* Because this is a template, the arguments will still be
8340 dependent, even after substitution. If
8341 PROCESSING_TEMPLATE_DECL is not set, the dependency
8342 predicates will short-circuit. */
8343 ++processing_template_decl;
8344 full_args = tsubst_template_args (tmpl_args, args,
8346 --processing_template_decl;
8347 if (full_args == error_mark_node)
8348 return error_mark_node;
8350 /* tsubst_template_args doesn't copy the vector if
8351 nothing changed. But, *something* should have
8353 gcc_assert (full_args != tmpl_args);
8355 hash = hash_tmpl_and_args (t, full_args);
8356 spec = retrieve_specialization (t, full_args, hash);
8357 if (spec != NULL_TREE)
8363 /* Make a new template decl. It will be similar to the
8364 original, but will record the current template arguments.
8365 We also create a new function declaration, which is just
8366 like the old one, but points to this new template, rather
8367 than the old one. */
8369 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
8370 TREE_CHAIN (r) = NULL_TREE;
8372 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
8374 if (TREE_CODE (decl) == TYPE_DECL)
8377 ++processing_template_decl;
8378 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8379 --processing_template_decl;
8380 if (new_type == error_mark_node)
8381 return error_mark_node;
8383 TREE_TYPE (r) = new_type;
8384 CLASSTYPE_TI_TEMPLATE (new_type) = r;
8385 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
8386 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
8387 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
8392 ++processing_template_decl;
8393 new_decl = tsubst (decl, args, complain, in_decl);
8394 --processing_template_decl;
8395 if (new_decl == error_mark_node)
8396 return error_mark_node;
8398 DECL_TEMPLATE_RESULT (r) = new_decl;
8399 DECL_TI_TEMPLATE (new_decl) = r;
8400 TREE_TYPE (r) = TREE_TYPE (new_decl);
8401 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
8402 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
8405 SET_DECL_IMPLICIT_INSTANTIATION (r);
8406 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
8407 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
8409 /* The template parameters for this new template are all the
8410 template parameters for the old template, except the
8411 outermost level of parameters. */
8412 DECL_TEMPLATE_PARMS (r)
8413 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
8416 if (PRIMARY_TEMPLATE_P (t))
8417 DECL_PRIMARY_TEMPLATE (r) = r;
8419 if (TREE_CODE (decl) != TYPE_DECL)
8420 /* Record this non-type partial instantiation. */
8421 register_specialization (r, t,
8422 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
8430 tree argvec = NULL_TREE;
8438 /* Nobody should be tsubst'ing into non-template functions. */
8439 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
8441 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
8446 /* If T is not dependent, just return it. We have to
8447 increment PROCESSING_TEMPLATE_DECL because
8448 value_dependent_expression_p assumes that nothing is
8449 dependent when PROCESSING_TEMPLATE_DECL is zero. */
8450 ++processing_template_decl;
8451 dependent_p = value_dependent_expression_p (t);
8452 --processing_template_decl;
8456 /* Calculate the most general template of which R is a
8457 specialization, and the complete set of arguments used to
8459 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
8460 argvec = tsubst_template_args (DECL_TI_ARGS
8461 (DECL_TEMPLATE_RESULT (gen_tmpl)),
8462 args, complain, in_decl);
8464 /* Check to see if we already have this specialization. */
8465 hash = hash_tmpl_and_args (gen_tmpl, argvec);
8466 spec = retrieve_specialization (gen_tmpl, argvec, hash);
8474 /* We can see more levels of arguments than parameters if
8475 there was a specialization of a member template, like
8478 template <class T> struct S { template <class U> void f(); }
8479 template <> template <class U> void S<int>::f(U);
8481 Here, we'll be substituting into the specialization,
8482 because that's where we can find the code we actually
8483 want to generate, but we'll have enough arguments for
8484 the most general template.
8486 We also deal with the peculiar case:
8488 template <class T> struct S {
8489 template <class U> friend void f();
8491 template <class U> void f() {}
8493 template void f<double>();
8495 Here, the ARGS for the instantiation of will be {int,
8496 double}. But, we only need as many ARGS as there are
8497 levels of template parameters in CODE_PATTERN. We are
8498 careful not to get fooled into reducing the ARGS in
8501 template <class T> struct S { template <class U> void f(U); }
8502 template <class T> template <> void S<T>::f(int) {}
8504 which we can spot because the pattern will be a
8505 specialization in this case. */
8506 args_depth = TMPL_ARGS_DEPTH (args);
8508 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
8509 if (args_depth > parms_depth
8510 && !DECL_TEMPLATE_SPECIALIZATION (t))
8511 args = get_innermost_template_args (args, parms_depth);
8515 /* This special case arises when we have something like this:
8517 template <class T> struct S {
8518 friend void f<int>(int, double);
8521 Here, the DECL_TI_TEMPLATE for the friend declaration
8522 will be an IDENTIFIER_NODE. We are being called from
8523 tsubst_friend_function, and we want only to create a
8524 new decl (R) with appropriate types so that we can call
8525 determine_specialization. */
8526 gen_tmpl = NULL_TREE;
8529 if (DECL_CLASS_SCOPE_P (t))
8531 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
8535 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
8536 complain, t, /*entering_scope=*/1);
8541 ctx = DECL_CONTEXT (t);
8543 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8544 if (type == error_mark_node)
8545 return error_mark_node;
8547 /* We do NOT check for matching decls pushed separately at this
8548 point, as they may not represent instantiations of this
8549 template, and in any case are considered separate under the
8552 DECL_USE_TEMPLATE (r) = 0;
8553 TREE_TYPE (r) = type;
8554 /* Clear out the mangled name and RTL for the instantiation. */
8555 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8556 SET_DECL_RTL (r, NULL_RTX);
8557 /* Leave DECL_INITIAL set on deleted instantiations. */
8558 if (!DECL_DELETED_FN (r))
8559 DECL_INITIAL (r) = NULL_TREE;
8560 DECL_CONTEXT (r) = ctx;
8562 if (member && DECL_CONV_FN_P (r))
8563 /* Type-conversion operator. Reconstruct the name, in
8564 case it's the name of one of the template's parameters. */
8565 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
8567 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
8569 DECL_RESULT (r) = NULL_TREE;
8571 TREE_STATIC (r) = 0;
8572 TREE_PUBLIC (r) = TREE_PUBLIC (t);
8573 DECL_EXTERNAL (r) = 1;
8574 /* If this is an instantiation of a function with internal
8575 linkage, we already know what object file linkage will be
8576 assigned to the instantiation. */
8577 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
8578 DECL_DEFER_OUTPUT (r) = 0;
8579 TREE_CHAIN (r) = NULL_TREE;
8580 DECL_PENDING_INLINE_INFO (r) = 0;
8581 DECL_PENDING_INLINE_P (r) = 0;
8582 DECL_SAVED_TREE (r) = NULL_TREE;
8583 DECL_STRUCT_FUNCTION (r) = NULL;
8585 /* We'll re-clone as appropriate in instantiate_template. */
8586 DECL_CLONED_FUNCTION (r) = NULL_TREE;
8588 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
8589 this in the special friend case mentioned above where
8590 GEN_TMPL is NULL. */
8593 DECL_TEMPLATE_INFO (r)
8594 = tree_cons (gen_tmpl, argvec, NULL_TREE);
8595 SET_DECL_IMPLICIT_INSTANTIATION (r);
8596 register_specialization (r, gen_tmpl, argvec, false, hash);
8598 /* We're not supposed to instantiate default arguments
8599 until they are called, for a template. But, for a
8602 template <class T> void f ()
8603 { extern void g(int i = T()); }
8605 we should do the substitution when the template is
8606 instantiated. We handle the member function case in
8607 instantiate_class_template since the default arguments
8608 might refer to other members of the class. */
8610 && !PRIMARY_TEMPLATE_P (gen_tmpl)
8611 && !uses_template_parms (argvec))
8612 tsubst_default_arguments (r);
8615 DECL_TEMPLATE_INFO (r) = NULL_TREE;
8617 /* Copy the list of befriending classes. */
8618 for (friends = &DECL_BEFRIENDING_CLASSES (r);
8620 friends = &TREE_CHAIN (*friends))
8622 *friends = copy_node (*friends);
8623 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
8628 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
8630 maybe_retrofit_in_chrg (r);
8631 if (DECL_CONSTRUCTOR_P (r))
8632 grok_ctor_properties (ctx, r);
8633 /* If this is an instantiation of a member template, clone it.
8634 If it isn't, that'll be handled by
8635 clone_constructors_and_destructors. */
8636 if (PRIMARY_TEMPLATE_P (gen_tmpl))
8637 clone_function_decl (r, /*update_method_vec_p=*/0);
8639 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r))
8640 && !grok_op_properties (r, (complain & tf_error) != 0))
8641 return error_mark_node;
8643 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
8644 SET_DECL_FRIEND_CONTEXT (r,
8645 tsubst (DECL_FRIEND_CONTEXT (t),
8646 args, complain, in_decl));
8648 /* Possibly limit visibility based on template args. */
8649 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8650 if (DECL_VISIBILITY_SPECIFIED (t))
8652 DECL_VISIBILITY_SPECIFIED (r) = 0;
8654 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8656 determine_visibility (r);
8658 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8659 args, complain, in_decl);
8665 tree type = NULL_TREE;
8667 tree expanded_types = NULL_TREE;
8668 tree prev_r = NULL_TREE;
8669 tree first_r = NULL_TREE;
8671 if (FUNCTION_PARAMETER_PACK_P (t))
8673 /* If there is a local specialization that isn't a
8674 parameter pack, it means that we're doing a "simple"
8675 substitution from inside tsubst_pack_expansion. Just
8676 return the local specialization (which will be a single
8678 tree spec = retrieve_local_specialization (t);
8680 && TREE_CODE (spec) == PARM_DECL
8681 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION)
8684 /* Expand the TYPE_PACK_EXPANSION that provides the types for
8685 the parameters in this function parameter pack. */
8686 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args,
8688 if (TREE_CODE (expanded_types) == TREE_VEC)
8690 len = TREE_VEC_LENGTH (expanded_types);
8692 /* Zero-length parameter packs are boring. Just substitute
8695 return tsubst (TREE_CHAIN (t), args, complain,
8700 /* All we did was update the type. Make a note of that. */
8701 type = expanded_types;
8702 expanded_types = NULL_TREE;
8706 /* Loop through all of the parameter's we'll build. When T is
8707 a function parameter pack, LEN is the number of expanded
8708 types in EXPANDED_TYPES; otherwise, LEN is 1. */
8710 for (i = 0; i < len; ++i)
8714 if (DECL_TEMPLATE_PARM_P (t))
8715 SET_DECL_TEMPLATE_PARM_P (r);
8718 /* We're on the Ith parameter of the function parameter
8721 /* Get the Ith type. */
8722 type = TREE_VEC_ELT (expanded_types, i);
8725 /* Rename the parameter to include the index. */
8727 make_ith_pack_parameter_name (DECL_NAME (r), i);
8730 /* We're dealing with a normal parameter. */
8731 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8733 type = type_decays_to (type);
8734 TREE_TYPE (r) = type;
8735 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8737 if (DECL_INITIAL (r))
8739 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
8740 DECL_INITIAL (r) = TREE_TYPE (r);
8742 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
8746 DECL_CONTEXT (r) = NULL_TREE;
8748 if (!DECL_TEMPLATE_PARM_P (r))
8749 DECL_ARG_TYPE (r) = type_passed_as (type);
8751 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8752 args, complain, in_decl);
8754 /* Keep track of the first new parameter we
8755 generate. That's what will be returned to the
8760 /* Build a proper chain of parameters when substituting
8761 into a function parameter pack. */
8763 TREE_CHAIN (prev_r) = r;
8767 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
8768 complain, TREE_CHAIN (t));
8770 /* FIRST_R contains the start of the chain we've built. */
8780 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8781 if (type == error_mark_node)
8782 return error_mark_node;
8783 TREE_TYPE (r) = type;
8784 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8786 /* DECL_INITIAL gives the number of bits in a bit-field. */
8788 = tsubst_expr (DECL_INITIAL (t), args,
8790 /*integral_constant_expression_p=*/true);
8791 /* We don't have to set DECL_CONTEXT here; it is set by
8792 finish_member_declaration. */
8793 TREE_CHAIN (r) = NULL_TREE;
8794 if (VOID_TYPE_P (type))
8795 error ("instantiation of %q+D as type %qT", r, type);
8797 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0,
8798 args, complain, in_decl);
8803 /* We reach here only for member using decls. */
8804 if (DECL_DEPENDENT_P (t))
8806 r = do_class_using_decl
8807 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
8808 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
8810 r = error_mark_node;
8813 TREE_PROTECTED (r) = TREE_PROTECTED (t);
8814 TREE_PRIVATE (r) = TREE_PRIVATE (t);
8820 TREE_CHAIN (r) = NULL_TREE;
8827 tree argvec = NULL_TREE;
8828 tree gen_tmpl = NULL_TREE;
8830 tree tmpl = NULL_TREE;
8832 tree type = NULL_TREE;
8835 if (TREE_CODE (t) == TYPE_DECL
8836 && t == TYPE_MAIN_DECL (TREE_TYPE (t)))
8838 /* If this is the canonical decl, we don't have to
8839 mess with instantiations, and often we can't (for
8840 typename, template type parms and such). Note that
8841 TYPE_NAME is not correct for the above test if
8842 we've copied the type for a typedef. */
8843 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8844 if (type == error_mark_node)
8845 return error_mark_node;
8846 r = TYPE_NAME (type);
8850 /* Check to see if we already have the specialization we
8853 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t))
8855 /* T is a static data member or namespace-scope entity.
8856 We have to substitute into namespace-scope variables
8857 (even though such entities are never templates) because
8860 template <class T> void f() { extern T t; }
8862 where the entity referenced is not known until
8863 instantiation time. */
8865 ctx = DECL_CONTEXT (t);
8866 if (DECL_CLASS_SCOPE_P (t))
8868 ctx = tsubst_aggr_type (ctx, args,
8870 in_decl, /*entering_scope=*/1);
8871 /* If CTX is unchanged, then T is in fact the
8872 specialization we want. That situation occurs when
8873 referencing a static data member within in its own
8874 class. We can use pointer equality, rather than
8875 same_type_p, because DECL_CONTEXT is always
8877 if (ctx == DECL_CONTEXT (t))
8883 tmpl = DECL_TI_TEMPLATE (t);
8884 gen_tmpl = most_general_template (tmpl);
8885 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
8886 hash = hash_tmpl_and_args (gen_tmpl, argvec);
8887 spec = retrieve_specialization (gen_tmpl, argvec, hash);
8892 /* A local variable. */
8894 /* Subsequent calls to pushdecl will fill this in. */
8896 spec = retrieve_local_specialization (t);
8898 /* If we already have the specialization we need, there is
8899 nothing more to do. */
8906 /* Create a new node for the specialization we need. */
8908 if (type == NULL_TREE)
8909 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8910 if (TREE_CODE (r) == VAR_DECL)
8912 /* Even if the original location is out of scope, the
8913 newly substituted one is not. */
8914 DECL_DEAD_FOR_LOCAL (r) = 0;
8915 DECL_INITIALIZED_P (r) = 0;
8916 DECL_TEMPLATE_INSTANTIATED (r) = 0;
8917 if (type == error_mark_node)
8918 return error_mark_node;
8919 if (TREE_CODE (type) == FUNCTION_TYPE)
8921 /* It may seem that this case cannot occur, since:
8926 declares a function, not a variable. However:
8929 template <typename T> void g() { T t; }
8930 template void g<f>();
8932 is an attempt to declare a variable with function
8934 error ("variable %qD has function type",
8935 /* R is not yet sufficiently initialized, so we
8936 just use its name. */
8938 return error_mark_node;
8940 type = complete_type (type);
8941 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
8942 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
8943 type = check_var_type (DECL_NAME (r), type);
8945 if (DECL_HAS_VALUE_EXPR_P (t))
8947 tree ve = DECL_VALUE_EXPR (t);
8948 ve = tsubst_expr (ve, args, complain, in_decl,
8949 /*constant_expression_p=*/false);
8950 SET_DECL_VALUE_EXPR (r, ve);
8953 else if (DECL_SELF_REFERENCE_P (t))
8954 SET_DECL_SELF_REFERENCE_P (r);
8955 TREE_TYPE (r) = type;
8956 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
8957 DECL_CONTEXT (r) = ctx;
8958 /* Clear out the mangled name and RTL for the instantiation. */
8959 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
8960 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8961 SET_DECL_RTL (r, NULL_RTX);
8962 /* The initializer must not be expanded until it is required;
8964 DECL_INITIAL (r) = NULL_TREE;
8965 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
8966 SET_DECL_RTL (r, NULL_RTX);
8967 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
8968 if (TREE_CODE (r) == VAR_DECL)
8970 /* Possibly limit visibility based on template args. */
8971 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT;
8972 if (DECL_VISIBILITY_SPECIFIED (t))
8974 DECL_VISIBILITY_SPECIFIED (r) = 0;
8976 = remove_attribute ("visibility", DECL_ATTRIBUTES (r));
8978 determine_visibility (r);
8980 /* Preserve a typedef that names a type. */
8981 else if (TREE_CODE (r) == TYPE_DECL
8982 && DECL_ORIGINAL_TYPE (t)
8983 && type != error_mark_node)
8985 DECL_ORIGINAL_TYPE (r) = tsubst (DECL_ORIGINAL_TYPE (t),
8986 args, complain, in_decl);
8987 TREE_TYPE (r) = type = build_variant_type_copy (type);
8988 TYPE_NAME (type) = r;
8993 /* A static data member declaration is always marked
8994 external when it is declared in-class, even if an
8995 initializer is present. We mimic the non-template
8997 DECL_EXTERNAL (r) = 1;
8999 register_specialization (r, gen_tmpl, argvec, false, hash);
9000 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
9001 SET_DECL_IMPLICIT_INSTANTIATION (r);
9004 register_local_specialization (r, t);
9006 TREE_CHAIN (r) = NULL_TREE;
9008 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r),
9009 (int) ATTR_FLAG_TYPE_IN_PLACE,
9010 args, complain, in_decl);
9019 /* Restore the file and line information. */
9020 input_location = saved_loc;
9025 /* Substitute into the ARG_TYPES of a function type. */
9028 tsubst_arg_types (tree arg_types,
9030 tsubst_flags_t complain,
9033 tree remaining_arg_types;
9034 tree type = NULL_TREE;
9036 tree expanded_args = NULL_TREE;
9039 if (!arg_types || arg_types == void_list_node)
9042 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
9043 args, complain, in_decl);
9044 if (remaining_arg_types == error_mark_node)
9045 return error_mark_node;
9047 if (PACK_EXPANSION_P (TREE_VALUE (arg_types)))
9049 /* For a pack expansion, perform substitution on the
9050 entire expression. Later on, we'll handle the arguments
9052 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types),
9053 args, complain, in_decl);
9055 if (TREE_CODE (expanded_args) == TREE_VEC)
9056 /* So that we'll spin through the parameters, one by one. */
9057 i = TREE_VEC_LENGTH (expanded_args);
9060 /* We only partially substituted into the parameter
9061 pack. Our type is TYPE_PACK_EXPANSION. */
9062 type = expanded_args;
9063 expanded_args = NULL_TREE;
9071 type = TREE_VEC_ELT (expanded_args, i);
9073 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
9075 if (type == error_mark_node)
9076 return error_mark_node;
9077 if (VOID_TYPE_P (type))
9079 if (complain & tf_error)
9081 error ("invalid parameter type %qT", type);
9083 error ("in declaration %q+D", in_decl);
9085 return error_mark_node;
9088 /* Do array-to-pointer, function-to-pointer conversion, and ignore
9089 top-level qualifiers as required. */
9090 type = TYPE_MAIN_VARIANT (type_decays_to (type));
9092 /* We do not substitute into default arguments here. The standard
9093 mandates that they be instantiated only when needed, which is
9094 done in build_over_call. */
9095 default_arg = TREE_PURPOSE (arg_types);
9097 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
9099 /* We've instantiated a template before its default arguments
9100 have been parsed. This can happen for a nested template
9101 class, and is not an error unless we require the default
9102 argument in a call of this function. */
9103 remaining_arg_types =
9104 tree_cons (default_arg, type, remaining_arg_types);
9105 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg),
9106 remaining_arg_types);
9109 remaining_arg_types =
9110 hash_tree_cons (default_arg, type, remaining_arg_types);
9113 return remaining_arg_types;
9116 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
9117 *not* handle the exception-specification for FNTYPE, because the
9118 initial substitution of explicitly provided template parameters
9119 during argument deduction forbids substitution into the
9120 exception-specification:
9124 All references in the function type of the function template to the
9125 corresponding template parameters are replaced by the specified tem-
9126 plate argument values. If a substitution in a template parameter or
9127 in the function type of the function template results in an invalid
9128 type, type deduction fails. [Note: The equivalent substitution in
9129 exception specifications is done only when the function is instanti-
9130 ated, at which point a program is ill-formed if the substitution
9131 results in an invalid type.] */
9134 tsubst_function_type (tree t,
9136 tsubst_flags_t complain,
9143 /* The TYPE_CONTEXT is not used for function/method types. */
9144 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
9146 /* Substitute the return type. */
9147 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
9148 if (return_type == error_mark_node)
9149 return error_mark_node;
9150 /* The standard does not presently indicate that creation of a
9151 function type with an invalid return type is a deduction failure.
9152 However, that is clearly analogous to creating an array of "void"
9153 or a reference to a reference. This is core issue #486. */
9154 if (TREE_CODE (return_type) == ARRAY_TYPE
9155 || TREE_CODE (return_type) == FUNCTION_TYPE)
9157 if (complain & tf_error)
9159 if (TREE_CODE (return_type) == ARRAY_TYPE)
9160 error ("function returning an array");
9162 error ("function returning a function");
9164 return error_mark_node;
9167 /* Substitute the argument types. */
9168 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
9170 if (arg_types == error_mark_node)
9171 return error_mark_node;
9173 /* Construct a new type node and return it. */
9174 if (TREE_CODE (t) == FUNCTION_TYPE)
9175 fntype = build_function_type (return_type, arg_types);
9178 tree r = TREE_TYPE (TREE_VALUE (arg_types));
9179 if (! MAYBE_CLASS_TYPE_P (r))
9183 Type deduction may fail for any of the following
9186 -- Attempting to create "pointer to member of T" when T
9187 is not a class type. */
9188 if (complain & tf_error)
9189 error ("creating pointer to member function of non-class type %qT",
9191 return error_mark_node;
9194 fntype = build_method_type_directly (r, return_type,
9195 TREE_CHAIN (arg_types));
9197 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
9198 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
9203 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
9204 ARGS into that specification, and return the substituted
9205 specification. If there is no specification, return NULL_TREE. */
9208 tsubst_exception_specification (tree fntype,
9210 tsubst_flags_t complain,
9216 specs = TYPE_RAISES_EXCEPTIONS (fntype);
9217 new_specs = NULL_TREE;
9220 if (! TREE_VALUE (specs))
9227 tree expanded_specs = NULL_TREE;
9229 if (PACK_EXPANSION_P (TREE_VALUE (specs)))
9231 /* Expand the pack expansion type. */
9232 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs),
9236 if (expanded_specs == error_mark_node)
9237 return error_mark_node;
9238 else if (TREE_CODE (expanded_specs) == TREE_VEC)
9239 len = TREE_VEC_LENGTH (expanded_specs);
9242 /* We're substituting into a member template, so
9243 we got a TYPE_PACK_EXPANSION back. Add that
9244 expansion and move on. */
9245 gcc_assert (TREE_CODE (expanded_specs)
9246 == TYPE_PACK_EXPANSION);
9247 new_specs = add_exception_specifier (new_specs,
9250 specs = TREE_CHAIN (specs);
9255 for (i = 0; i < len; ++i)
9258 spec = TREE_VEC_ELT (expanded_specs, i);
9260 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
9261 if (spec == error_mark_node)
9263 new_specs = add_exception_specifier (new_specs, spec,
9267 specs = TREE_CHAIN (specs);
9273 /* Take the tree structure T and replace template parameters used
9274 therein with the argument vector ARGS. IN_DECL is an associated
9275 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
9276 Issue error and warning messages under control of COMPLAIN. Note
9277 that we must be relatively non-tolerant of extensions here, in
9278 order to preserve conformance; if we allow substitutions that
9279 should not be allowed, we may allow argument deductions that should
9280 not succeed, and therefore report ambiguous overload situations
9281 where there are none. In theory, we could allow the substitution,
9282 but indicate that it should have failed, and allow our caller to
9283 make sure that the right thing happens, but we don't try to do this
9286 This function is used for dealing with types, decls and the like;
9287 for expressions, use tsubst_expr or tsubst_copy. */
9290 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
9294 if (t == NULL_TREE || t == error_mark_node
9295 || t == integer_type_node
9296 || t == void_type_node
9297 || t == char_type_node
9298 || t == unknown_type_node
9299 || TREE_CODE (t) == NAMESPACE_DECL)
9303 return tsubst_decl (t, args, complain);
9305 if (args == NULL_TREE)
9308 if (TREE_CODE (t) == IDENTIFIER_NODE)
9309 type = IDENTIFIER_TYPE_VALUE (t);
9311 type = TREE_TYPE (t);
9313 gcc_assert (type != unknown_type_node);
9315 /* Reuse typedefs. We need to do this to handle dependent attributes,
9316 such as attribute aligned. */
9319 && TYPE_NAME (t) != TYPE_MAIN_DECL (t))
9321 tree decl = TYPE_NAME (t);
9323 if (DECL_CLASS_SCOPE_P (decl)
9324 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
9325 && uses_template_parms (DECL_CONTEXT (decl)))
9327 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
9328 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl);
9329 r = retrieve_specialization (tmpl, gen_args, 0);
9331 else if (DECL_FUNCTION_SCOPE_P (decl)
9332 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl))
9333 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl))))
9334 r = retrieve_local_specialization (decl);
9336 /* The typedef is from a non-template context. */
9342 r = cp_build_qualified_type_real
9343 (r, cp_type_quals (t) | cp_type_quals (r),
9344 complain | tf_ignore_bad_quals);
9347 /* Else we must be instantiating the typedef, so fall through. */
9351 && TREE_CODE (t) != TYPENAME_TYPE
9352 && TREE_CODE (t) != IDENTIFIER_NODE
9353 && TREE_CODE (t) != FUNCTION_TYPE
9354 && TREE_CODE (t) != METHOD_TYPE)
9355 type = tsubst (type, args, complain, in_decl);
9356 if (type == error_mark_node)
9357 return error_mark_node;
9359 switch (TREE_CODE (t))
9364 return tsubst_aggr_type (t, args, complain, in_decl,
9365 /*entering_scope=*/0);
9368 case IDENTIFIER_NODE:
9380 if (t == integer_type_node)
9383 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
9384 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
9388 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
9390 max = tsubst_expr (omax, args, complain, in_decl,
9391 /*integral_constant_expression_p=*/false);
9393 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if
9395 if (TREE_CODE (max) == NOP_EXPR
9396 && TREE_SIDE_EFFECTS (omax)
9397 && !TREE_TYPE (max))
9398 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0));
9400 max = fold_decl_constant_value (max);
9402 /* If we're in a partial instantiation, preserve the magic NOP_EXPR
9403 with TREE_SIDE_EFFECTS that indicates this is not an integral
9404 constant expression. */
9405 if (processing_template_decl
9406 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR)
9408 gcc_assert (TREE_CODE (max) == NOP_EXPR);
9409 TREE_SIDE_EFFECTS (max) = 1;
9412 if (TREE_CODE (max) != INTEGER_CST
9413 && !at_function_scope_p ()
9414 && !TREE_SIDE_EFFECTS (max)
9415 && !value_dependent_expression_p (max))
9417 if (complain & tf_error)
9418 error ("array bound is not an integer constant");
9419 return error_mark_node;
9424 Type deduction may fail for any of the following
9427 Attempting to create an array with a size that is
9428 zero or negative. */
9429 if (integer_zerop (max) && !(complain & tf_error))
9430 /* We must fail if performing argument deduction (as
9431 indicated by the state of complain), so that
9432 another substitution can be found. */
9433 return error_mark_node;
9434 else if (TREE_CODE (max) == INTEGER_CST
9435 && INT_CST_LT (max, integer_zero_node))
9437 if (complain & tf_error)
9438 error ("creating array with negative size (%qE)", max);
9440 return error_mark_node;
9443 return compute_array_index_type (NULL_TREE, max);
9446 case TEMPLATE_TYPE_PARM:
9447 case TEMPLATE_TEMPLATE_PARM:
9448 case BOUND_TEMPLATE_TEMPLATE_PARM:
9449 case TEMPLATE_PARM_INDEX:
9454 tree arg = NULL_TREE;
9458 gcc_assert (TREE_VEC_LENGTH (args) > 0);
9459 template_parm_level_and_index (t, &level, &idx);
9461 levels = TMPL_ARGS_DEPTH (args);
9462 if (level <= levels)
9464 arg = TMPL_ARG (args, level, idx);
9466 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT)
9467 /* See through ARGUMENT_PACK_SELECT arguments. */
9468 arg = ARGUMENT_PACK_SELECT_ARG (arg);
9471 if (arg == error_mark_node)
9472 return error_mark_node;
9473 else if (arg != NULL_TREE)
9475 if (ARGUMENT_PACK_P (arg))
9476 /* If ARG is an argument pack, we don't actually want to
9477 perform a substitution here, because substitutions
9478 for argument packs are only done
9479 element-by-element. We can get to this point when
9480 substituting the type of a non-type template
9481 parameter pack, when that type actually contains
9482 template parameter packs from an outer template, e.g.,
9484 template<typename... Types> struct A {
9485 template<Types... Values> struct B { };
9489 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
9492 gcc_assert (TYPE_P (arg));
9494 /* cv-quals from the template are discarded when
9495 substituting in a function or reference type. */
9496 if (TREE_CODE (arg) == FUNCTION_TYPE
9497 || TREE_CODE (arg) == METHOD_TYPE
9498 || TREE_CODE (arg) == REFERENCE_TYPE)
9499 quals = cp_type_quals (arg);
9501 quals = cp_type_quals (arg) | cp_type_quals (t);
9503 return cp_build_qualified_type_real
9504 (arg, quals, complain | tf_ignore_bad_quals);
9506 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9508 /* We are processing a type constructed from a
9509 template template parameter. */
9510 tree argvec = tsubst (TYPE_TI_ARGS (t),
9511 args, complain, in_decl);
9512 if (argvec == error_mark_node)
9513 return error_mark_node;
9515 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
9516 are resolving nested-types in the signature of a
9517 member function templates. Otherwise ARG is a
9518 TEMPLATE_DECL and is the real template to be
9520 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
9521 arg = TYPE_NAME (arg);
9523 r = lookup_template_class (arg,
9526 /*entering_scope=*/0,
9528 return cp_build_qualified_type_real
9529 (r, TYPE_QUALS (t), complain);
9532 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
9537 /* This can happen during the attempted tsubst'ing in
9538 unify. This means that we don't yet have any information
9539 about the template parameter in question. */
9542 /* If we get here, we must have been looking at a parm for a
9543 more deeply nested template. Make a new version of this
9544 template parameter, but with a lower level. */
9545 switch (TREE_CODE (t))
9547 case TEMPLATE_TYPE_PARM:
9548 case TEMPLATE_TEMPLATE_PARM:
9549 case BOUND_TEMPLATE_TEMPLATE_PARM:
9550 if (cp_type_quals (t))
9552 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
9553 r = cp_build_qualified_type_real
9554 (r, cp_type_quals (t),
9555 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
9556 ? tf_ignore_bad_quals : 0));
9561 TEMPLATE_TYPE_PARM_INDEX (r)
9562 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
9563 r, levels, args, complain);
9564 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
9565 TYPE_MAIN_VARIANT (r) = r;
9566 TYPE_POINTER_TO (r) = NULL_TREE;
9567 TYPE_REFERENCE_TO (r) = NULL_TREE;
9569 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM)
9570 /* We have reduced the level of the template
9571 template parameter, but not the levels of its
9572 template parameters, so canonical_type_parameter
9573 will not be able to find the canonical template
9574 template parameter for this level. Thus, we
9575 require structural equality checking to compare
9576 TEMPLATE_TEMPLATE_PARMs. */
9577 SET_TYPE_STRUCTURAL_EQUALITY (r);
9578 else if (TYPE_STRUCTURAL_EQUALITY_P (t))
9579 SET_TYPE_STRUCTURAL_EQUALITY (r);
9581 TYPE_CANONICAL (r) = canonical_type_parameter (r);
9583 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
9585 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
9587 if (argvec == error_mark_node)
9588 return error_mark_node;
9590 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
9591 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
9596 case TEMPLATE_PARM_INDEX:
9597 r = reduce_template_parm_level (t, type, levels, args, complain);
9609 tree purpose, value, chain;
9611 if (t == void_list_node)
9614 purpose = TREE_PURPOSE (t);
9617 purpose = tsubst (purpose, args, complain, in_decl);
9618 if (purpose == error_mark_node)
9619 return error_mark_node;
9621 value = TREE_VALUE (t);
9624 value = tsubst (value, args, complain, in_decl);
9625 if (value == error_mark_node)
9626 return error_mark_node;
9628 chain = TREE_CHAIN (t);
9629 if (chain && chain != void_type_node)
9631 chain = tsubst (chain, args, complain, in_decl);
9632 if (chain == error_mark_node)
9633 return error_mark_node;
9635 if (purpose == TREE_PURPOSE (t)
9636 && value == TREE_VALUE (t)
9637 && chain == TREE_CHAIN (t))
9639 return hash_tree_cons (purpose, value, chain);
9643 /* We should never be tsubsting a binfo. */
9647 /* A vector of template arguments. */
9649 return tsubst_template_args (t, args, complain, in_decl);
9652 case REFERENCE_TYPE:
9654 enum tree_code code;
9656 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
9659 code = TREE_CODE (t);
9664 Type deduction may fail for any of the following
9667 -- Attempting to create a pointer to reference type.
9668 -- Attempting to create a reference to a reference type or
9669 a reference to void.
9671 Core issue 106 says that creating a reference to a reference
9672 during instantiation is no longer a cause for failure. We
9673 only enforce this check in strict C++98 mode. */
9674 if ((TREE_CODE (type) == REFERENCE_TYPE
9675 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE))
9676 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
9678 static location_t last_loc;
9680 /* We keep track of the last time we issued this error
9681 message to avoid spewing a ton of messages during a
9682 single bad template instantiation. */
9683 if (complain & tf_error
9684 && last_loc != input_location)
9686 if (TREE_CODE (type) == VOID_TYPE)
9687 error ("forming reference to void");
9689 error ("forming %s to reference type %qT",
9690 (code == POINTER_TYPE) ? "pointer" : "reference",
9692 last_loc = input_location;
9695 return error_mark_node;
9697 else if (code == POINTER_TYPE)
9699 r = build_pointer_type (type);
9700 if (TREE_CODE (type) == METHOD_TYPE)
9701 r = build_ptrmemfunc_type (r);
9703 else if (TREE_CODE (type) == REFERENCE_TYPE)
9704 /* In C++0x, during template argument substitution, when there is an
9705 attempt to create a reference to a reference type, reference
9706 collapsing is applied as described in [14.3.1/4 temp.arg.type]:
9708 "If a template-argument for a template-parameter T names a type
9709 that is a reference to a type A, an attempt to create the type
9710 'lvalue reference to cv T' creates the type 'lvalue reference to
9711 A,' while an attempt to create the type type rvalue reference to
9712 cv T' creates the type T"
9714 r = cp_build_reference_type
9716 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type));
9718 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t));
9719 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
9721 if (r != error_mark_node)
9722 /* Will this ever be needed for TYPE_..._TO values? */
9729 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
9730 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r))
9734 Type deduction may fail for any of the following
9737 -- Attempting to create "pointer to member of T" when T
9738 is not a class type. */
9739 if (complain & tf_error)
9740 error ("creating pointer to member of non-class type %qT", r);
9741 return error_mark_node;
9743 if (TREE_CODE (type) == REFERENCE_TYPE)
9745 if (complain & tf_error)
9746 error ("creating pointer to member reference type %qT", type);
9747 return error_mark_node;
9749 if (TREE_CODE (type) == VOID_TYPE)
9751 if (complain & tf_error)
9752 error ("creating pointer to member of type void");
9753 return error_mark_node;
9755 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
9756 if (TREE_CODE (type) == FUNCTION_TYPE)
9758 /* The type of the implicit object parameter gets its
9759 cv-qualifiers from the FUNCTION_TYPE. */
9761 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
9762 cp_type_quals (type));
9764 method_type = build_method_type_directly (this_type,
9766 TYPE_ARG_TYPES (type));
9767 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
9768 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
9772 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
9781 fntype = tsubst_function_type (t, args, complain, in_decl);
9782 if (fntype == error_mark_node)
9783 return error_mark_node;
9785 /* Substitute the exception specification. */
9786 specs = tsubst_exception_specification (t, args, complain,
9788 if (specs == error_mark_node)
9789 return error_mark_node;
9791 fntype = build_exception_variant (fntype, specs);
9796 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
9797 if (domain == error_mark_node)
9798 return error_mark_node;
9800 /* As an optimization, we avoid regenerating the array type if
9801 it will obviously be the same as T. */
9802 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
9805 /* These checks should match the ones in grokdeclarator.
9809 The deduction may fail for any of the following reasons:
9811 -- Attempting to create an array with an element type that
9812 is void, a function type, or a reference type, or [DR337]
9813 an abstract class type. */
9814 if (TREE_CODE (type) == VOID_TYPE
9815 || TREE_CODE (type) == FUNCTION_TYPE
9816 || TREE_CODE (type) == REFERENCE_TYPE)
9818 if (complain & tf_error)
9819 error ("creating array of %qT", type);
9820 return error_mark_node;
9822 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
9824 if (complain & tf_error)
9825 error ("creating array of %qT, which is an abstract class type",
9827 return error_mark_node;
9830 r = build_cplus_array_type (type, domain);
9832 if (TYPE_USER_ALIGN (t))
9834 TYPE_ALIGN (r) = TYPE_ALIGN (t);
9835 TYPE_USER_ALIGN (r) = 1;
9844 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9845 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9847 if (e1 == error_mark_node || e2 == error_mark_node)
9848 return error_mark_node;
9850 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
9856 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9857 if (e == error_mark_node)
9858 return error_mark_node;
9860 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
9865 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9866 in_decl, /*entering_scope=*/1);
9867 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
9870 if (ctx == error_mark_node || f == error_mark_node)
9871 return error_mark_node;
9873 if (!MAYBE_CLASS_TYPE_P (ctx))
9875 if (complain & tf_error)
9876 error ("%qT is not a class, struct, or union type", ctx);
9877 return error_mark_node;
9879 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
9881 /* Normally, make_typename_type does not require that the CTX
9882 have complete type in order to allow things like:
9884 template <class T> struct S { typename S<T>::X Y; };
9886 But, such constructs have already been resolved by this
9887 point, so here CTX really should have complete type, unless
9888 it's a partial instantiation. */
9889 ctx = complete_type (ctx);
9890 if (!COMPLETE_TYPE_P (ctx))
9892 if (complain & tf_error)
9893 cxx_incomplete_type_error (NULL_TREE, ctx);
9894 return error_mark_node;
9898 f = make_typename_type (ctx, f, typename_type,
9899 (complain & tf_error) | tf_keep_type_decl);
9900 if (f == error_mark_node)
9902 if (TREE_CODE (f) == TYPE_DECL)
9904 complain |= tf_ignore_bad_quals;
9908 if (TREE_CODE (f) != TYPENAME_TYPE)
9910 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
9911 error ("%qT resolves to %qT, which is not an enumeration type",
9913 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
9914 error ("%qT resolves to %qT, which is is not a class type",
9918 return cp_build_qualified_type_real
9919 (f, cp_type_quals (f) | cp_type_quals (t), complain);
9922 case UNBOUND_CLASS_TEMPLATE:
9924 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
9925 in_decl, /*entering_scope=*/1);
9926 tree name = TYPE_IDENTIFIER (t);
9927 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
9929 if (ctx == error_mark_node || name == error_mark_node)
9930 return error_mark_node;
9933 parm_list = tsubst_template_parms (parm_list, args, complain);
9934 return make_unbound_class_template (ctx, name, parm_list, complain);
9944 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9945 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl,
9946 /*integral_constant_expression_p=*/false);
9947 if (e1 == error_mark_node || e2 == error_mark_node)
9948 return error_mark_node;
9950 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
9955 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
9956 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
9957 if (e1 == error_mark_node || e2 == error_mark_node)
9958 return error_mark_node;
9960 return build_qualified_name (/*type=*/NULL_TREE,
9961 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
9968 type = finish_typeof (tsubst_expr
9969 (TYPEOF_TYPE_EXPR (t), args,
9971 /*integral_constant_expression_p=*/false));
9972 return cp_build_qualified_type_real (type,
9974 | cp_type_quals (type),
9982 ++cp_unevaluated_operand;
9983 ++c_inhibit_evaluation_warnings;
9985 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args,
9987 /*integral_constant_expression_p=*/false);
9989 --cp_unevaluated_operand;
9990 --c_inhibit_evaluation_warnings;
9993 finish_decltype_type (type,
9994 DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t));
9995 return cp_build_qualified_type_real (type,
9997 | cp_type_quals (type),
10001 case TYPE_ARGUMENT_PACK:
10002 case NONTYPE_ARGUMENT_PACK:
10004 tree r = make_node (TREE_CODE (t));
10006 tsubst_template_args (ARGUMENT_PACK_ARGS (t),
10010 SET_ARGUMENT_PACK_ARGS (r, packed_out);
10012 /* For template nontype argument packs, also substitute into
10014 if (TREE_CODE (t) == NONTYPE_ARGUMENT_PACK)
10015 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl);
10022 sorry ("use of %qs in template",
10023 tree_code_name [(int) TREE_CODE (t)]);
10024 return error_mark_node;
10028 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
10029 type of the expression on the left-hand side of the "." or "->"
10033 tsubst_baselink (tree baselink, tree object_type,
10034 tree args, tsubst_flags_t complain, tree in_decl)
10037 tree qualifying_scope;
10040 tree template_args = 0;
10041 bool template_id_p = false;
10043 /* A baselink indicates a function from a base class. Both the
10044 BASELINK_ACCESS_BINFO and the base class referenced may
10045 indicate bases of the template class, rather than the
10046 instantiated class. In addition, lookups that were not
10047 ambiguous before may be ambiguous now. Therefore, we perform
10048 the lookup again. */
10049 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
10050 qualifying_scope = tsubst (qualifying_scope, args,
10051 complain, in_decl);
10052 fns = BASELINK_FUNCTIONS (baselink);
10053 optype = BASELINK_OPTYPE (baselink);
10054 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
10056 template_id_p = true;
10057 template_args = TREE_OPERAND (fns, 1);
10058 fns = TREE_OPERAND (fns, 0);
10060 template_args = tsubst_template_args (template_args, args,
10061 complain, in_decl);
10063 name = DECL_NAME (get_first_fn (fns));
10064 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
10066 /* If lookup found a single function, mark it as used at this
10067 point. (If it lookup found multiple functions the one selected
10068 later by overload resolution will be marked as used at that
10070 if (BASELINK_P (baselink))
10071 fns = BASELINK_FUNCTIONS (baselink);
10072 if (!template_id_p && !really_overloaded_fn (fns))
10073 mark_used (OVL_CURRENT (fns));
10075 /* Add back the template arguments, if present. */
10076 if (BASELINK_P (baselink) && template_id_p)
10077 BASELINK_FUNCTIONS (baselink)
10078 = build_nt (TEMPLATE_ID_EXPR,
10079 BASELINK_FUNCTIONS (baselink),
10081 /* Update the conversion operator type. */
10082 BASELINK_OPTYPE (baselink)
10083 = tsubst (optype, args, complain, in_decl);
10086 object_type = current_class_type;
10087 return adjust_result_of_qualified_name_lookup (baselink,
10092 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
10093 true if the qualified-id will be a postfix-expression in-and-of
10094 itself; false if more of the postfix-expression follows the
10095 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
10099 tsubst_qualified_id (tree qualified_id, tree args,
10100 tsubst_flags_t complain, tree in_decl,
10101 bool done, bool address_p)
10107 tree template_args;
10109 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
10111 /* Figure out what name to look up. */
10112 name = TREE_OPERAND (qualified_id, 1);
10113 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
10115 is_template = true;
10116 template_args = TREE_OPERAND (name, 1);
10118 template_args = tsubst_template_args (template_args, args,
10119 complain, in_decl);
10120 name = TREE_OPERAND (name, 0);
10124 is_template = false;
10125 template_args = NULL_TREE;
10128 /* Substitute into the qualifying scope. When there are no ARGS, we
10129 are just trying to simplify a non-dependent expression. In that
10130 case the qualifying scope may be dependent, and, in any case,
10131 substituting will not help. */
10132 scope = TREE_OPERAND (qualified_id, 0);
10135 scope = tsubst (scope, args, complain, in_decl);
10136 expr = tsubst_copy (name, args, complain, in_decl);
10141 if (dependent_type_p (scope))
10143 tree type = NULL_TREE;
10144 if (DECL_P (expr) && !dependent_scope_p (scope))
10145 type = TREE_TYPE (expr);
10146 return build_qualified_name (type, scope, expr,
10147 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
10150 if (!BASELINK_P (name) && !DECL_P (expr))
10152 if (TREE_CODE (expr) == BIT_NOT_EXPR)
10154 /* A BIT_NOT_EXPR is used to represent a destructor. */
10155 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0)))
10157 error ("qualifying type %qT does not match destructor name ~%qT",
10158 scope, TREE_OPERAND (expr, 0));
10159 expr = error_mark_node;
10162 expr = lookup_qualified_name (scope, complete_dtor_identifier,
10163 /*is_type_p=*/0, false);
10166 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
10167 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
10168 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
10170 if (complain & tf_error)
10172 error ("dependent-name %qE is parsed as a non-type, but "
10173 "instantiation yields a type", qualified_id);
10174 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id);
10176 return error_mark_node;
10182 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
10184 /* Remember that there was a reference to this entity. */
10188 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
10190 if (complain & tf_error)
10191 qualified_name_lookup_error (scope,
10192 TREE_OPERAND (qualified_id, 1),
10193 expr, input_location);
10194 return error_mark_node;
10198 expr = lookup_template_function (expr, template_args);
10200 if (expr == error_mark_node && complain & tf_error)
10201 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
10202 expr, input_location);
10203 else if (TYPE_P (scope))
10205 expr = (adjust_result_of_qualified_name_lookup
10206 (expr, scope, current_class_type));
10207 expr = (finish_qualified_id_expr
10208 (scope, expr, done, address_p,
10209 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
10210 /*template_arg_p=*/false));
10213 /* Expressions do not generally have reference type. */
10214 if (TREE_CODE (expr) != SCOPE_REF
10215 /* However, if we're about to form a pointer-to-member, we just
10216 want the referenced member referenced. */
10217 && TREE_CODE (expr) != OFFSET_REF)
10218 expr = convert_from_reference (expr);
10223 /* Like tsubst, but deals with expressions. This function just replaces
10224 template parms; to finish processing the resultant expression, use
10228 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
10230 enum tree_code code;
10233 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE)
10236 code = TREE_CODE (t);
10241 r = retrieve_local_specialization (t);
10246 /* This can happen for a parameter name used later in a function
10247 declaration (such as in a late-specified return type). Just
10248 make a dummy decl, since it's only used for its type. */
10249 gcc_assert (cp_unevaluated_operand != 0);
10250 /* We copy T because want to tsubst the PARM_DECL only,
10251 not the following PARM_DECLs that are chained to T. */
10253 r = tsubst_decl (c, args, complain);
10254 /* Give it the template pattern as its context; its true context
10255 hasn't been instantiated yet and this is good enough for
10257 DECL_CONTEXT (r) = DECL_CONTEXT (t);
10260 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT)
10261 r = ARGUMENT_PACK_SELECT_ARG (r);
10270 if (DECL_TEMPLATE_PARM_P (t))
10271 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
10272 /* There is no need to substitute into namespace-scope
10274 if (DECL_NAMESPACE_SCOPE_P (t))
10276 /* If ARGS is NULL, then T is known to be non-dependent. */
10277 if (args == NULL_TREE)
10278 return integral_constant_value (t);
10280 /* Unfortunately, we cannot just call lookup_name here.
10283 template <int I> int f() {
10285 struct S { void g() { E e = a; } };
10288 When we instantiate f<7>::S::g(), say, lookup_name is not
10289 clever enough to find f<7>::a. */
10291 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
10292 /*entering_scope=*/0);
10294 for (v = TYPE_VALUES (enum_type);
10296 v = TREE_CHAIN (v))
10297 if (TREE_PURPOSE (v) == DECL_NAME (t))
10298 return TREE_VALUE (v);
10300 /* We didn't find the name. That should never happen; if
10301 name-lookup found it during preliminary parsing, we
10302 should find it again here during instantiation. */
10303 gcc_unreachable ();
10308 if (DECL_CONTEXT (t))
10312 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
10313 /*entering_scope=*/1);
10314 if (ctx != DECL_CONTEXT (t))
10316 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
10319 if (complain & tf_error)
10320 error ("using invalid field %qD", t);
10321 return error_mark_node;
10330 case FUNCTION_DECL:
10331 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
10332 || local_variable_p (t))
10333 t = tsubst (t, args, complain, in_decl);
10338 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
10340 case TEMPLATE_DECL:
10341 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
10342 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
10343 args, complain, in_decl);
10344 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
10345 return tsubst (t, args, complain, in_decl);
10346 else if (DECL_CLASS_SCOPE_P (t)
10347 && uses_template_parms (DECL_CONTEXT (t)))
10349 /* Template template argument like the following example need
10352 template <template <class> class TT> struct C {};
10353 template <class T> struct D {
10354 template <class U> struct E {};
10359 We are processing the template argument `E' in #1 for
10360 the template instantiation #2. Originally, `E' is a
10361 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
10362 have to substitute this with one having context `D<int>'. */
10364 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
10365 return lookup_field (context, DECL_NAME(t), 0, false);
10368 /* Ordinary template template argument. */
10372 case REINTERPRET_CAST_EXPR:
10373 case CONST_CAST_EXPR:
10374 case STATIC_CAST_EXPR:
10375 case DYNAMIC_CAST_EXPR:
10378 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10379 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10382 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
10384 /* We only want to compute the number of arguments. */
10385 tree expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args,
10386 complain, in_decl);
10389 if (TREE_CODE (expanded) == TREE_VEC)
10390 len = TREE_VEC_LENGTH (expanded);
10392 if (expanded == error_mark_node)
10393 return error_mark_node;
10394 else if (PACK_EXPANSION_P (expanded)
10395 || (TREE_CODE (expanded) == TREE_VEC
10397 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1))))
10399 if (TREE_CODE (expanded) == TREE_VEC)
10400 expanded = TREE_VEC_ELT (expanded, len - 1);
10402 if (TYPE_P (expanded))
10403 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR,
10404 complain & tf_error);
10406 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR,
10407 complain & tf_error);
10410 return build_int_cst (size_type_node, len);
10416 case TRUTH_NOT_EXPR:
10419 case UNARY_PLUS_EXPR: /* Unary + */
10424 case REALPART_EXPR:
10425 case IMAGPART_EXPR:
10427 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
10428 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
10430 case COMPONENT_REF:
10435 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
10436 name = TREE_OPERAND (t, 1);
10437 if (TREE_CODE (name) == BIT_NOT_EXPR)
10439 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10440 complain, in_decl);
10441 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10443 else if (TREE_CODE (name) == SCOPE_REF
10444 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
10446 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
10447 complain, in_decl);
10448 name = TREE_OPERAND (name, 1);
10449 name = tsubst_copy (TREE_OPERAND (name, 0), args,
10450 complain, in_decl);
10451 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
10452 name = build_qualified_name (/*type=*/NULL_TREE,
10454 /*template_p=*/false);
10456 else if (TREE_CODE (name) == BASELINK)
10457 name = tsubst_baselink (name,
10458 non_reference (TREE_TYPE (object)),
10462 name = tsubst_copy (name, args, complain, in_decl);
10463 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
10469 case TRUNC_DIV_EXPR:
10470 case CEIL_DIV_EXPR:
10471 case FLOOR_DIV_EXPR:
10472 case ROUND_DIV_EXPR:
10473 case EXACT_DIV_EXPR:
10477 case TRUNC_MOD_EXPR:
10478 case FLOOR_MOD_EXPR:
10479 case TRUTH_ANDIF_EXPR:
10480 case TRUTH_ORIF_EXPR:
10481 case TRUTH_AND_EXPR:
10482 case TRUTH_OR_EXPR:
10495 case COMPOUND_EXPR:
10498 case PREDECREMENT_EXPR:
10499 case PREINCREMENT_EXPR:
10500 case POSTDECREMENT_EXPR:
10501 case POSTINCREMENT_EXPR:
10503 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10504 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10507 return build_qualified_name (/*type=*/NULL_TREE,
10508 tsubst_copy (TREE_OPERAND (t, 0),
10509 args, complain, in_decl),
10510 tsubst_copy (TREE_OPERAND (t, 1),
10511 args, complain, in_decl),
10512 QUALIFIED_NAME_IS_TEMPLATE (t));
10517 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10518 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10519 NULL_TREE, NULL_TREE);
10523 int n = VL_EXP_OPERAND_LENGTH (t);
10524 tree result = build_vl_exp (CALL_EXPR, n);
10526 for (i = 0; i < n; i++)
10527 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args,
10528 complain, in_decl);
10534 case PSEUDO_DTOR_EXPR:
10537 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10538 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10539 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10540 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
10547 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10548 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
10549 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
10550 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
10557 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
10558 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
10559 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
10560 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
10564 case TEMPLATE_ID_EXPR:
10566 /* Substituted template arguments */
10567 tree fn = TREE_OPERAND (t, 0);
10568 tree targs = TREE_OPERAND (t, 1);
10570 fn = tsubst_copy (fn, args, complain, in_decl);
10572 targs = tsubst_template_args (targs, args, complain, in_decl);
10574 return lookup_template_function (fn, targs);
10579 tree purpose, value, chain;
10581 if (t == void_list_node)
10584 purpose = TREE_PURPOSE (t);
10586 purpose = tsubst_copy (purpose, args, complain, in_decl);
10587 value = TREE_VALUE (t);
10589 value = tsubst_copy (value, args, complain, in_decl);
10590 chain = TREE_CHAIN (t);
10591 if (chain && chain != void_type_node)
10592 chain = tsubst_copy (chain, args, complain, in_decl);
10593 if (purpose == TREE_PURPOSE (t)
10594 && value == TREE_VALUE (t)
10595 && chain == TREE_CHAIN (t))
10597 return tree_cons (purpose, value, chain);
10602 case ENUMERAL_TYPE:
10604 case TEMPLATE_TYPE_PARM:
10605 case TEMPLATE_TEMPLATE_PARM:
10606 case BOUND_TEMPLATE_TEMPLATE_PARM:
10607 case TEMPLATE_PARM_INDEX:
10609 case REFERENCE_TYPE:
10611 case FUNCTION_TYPE:
10614 case TYPENAME_TYPE:
10615 case UNBOUND_CLASS_TEMPLATE:
10617 case DECLTYPE_TYPE:
10619 return tsubst (t, args, complain, in_decl);
10621 case IDENTIFIER_NODE:
10622 if (IDENTIFIER_TYPENAME_P (t))
10624 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
10625 return mangle_conv_op_name_for_type (new_type);
10631 /* This is handled by tsubst_copy_and_build. */
10632 gcc_unreachable ();
10635 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
10637 tsubst (TREE_TYPE (t), args, complain, in_decl));
10639 case CLEANUP_POINT_EXPR:
10640 /* We shouldn't have built any of these during initial template
10641 generation. Instead, they should be built during instantiation
10642 in response to the saved STMT_IS_FULL_EXPR_P setting. */
10643 gcc_unreachable ();
10646 mark_used (TREE_OPERAND (t, 1));
10649 case EXPR_PACK_EXPANSION:
10650 error ("invalid use of pack expansion expression");
10651 return error_mark_node;
10653 case NONTYPE_ARGUMENT_PACK:
10654 error ("use %<...%> to expand argument pack");
10655 return error_mark_node;
10662 /* Like tsubst_copy, but specifically for OpenMP clauses. */
10665 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain,
10668 tree new_clauses = NULL, nc, oc;
10670 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc))
10672 nc = copy_node (oc);
10673 OMP_CLAUSE_CHAIN (nc) = new_clauses;
10676 switch (OMP_CLAUSE_CODE (nc))
10678 case OMP_CLAUSE_LASTPRIVATE:
10679 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc))
10681 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list ();
10682 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain,
10683 in_decl, /*integral_constant_expression_p=*/false);
10684 OMP_CLAUSE_LASTPRIVATE_STMT (nc)
10685 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc));
10688 case OMP_CLAUSE_PRIVATE:
10689 case OMP_CLAUSE_SHARED:
10690 case OMP_CLAUSE_FIRSTPRIVATE:
10691 case OMP_CLAUSE_REDUCTION:
10692 case OMP_CLAUSE_COPYIN:
10693 case OMP_CLAUSE_COPYPRIVATE:
10694 case OMP_CLAUSE_IF:
10695 case OMP_CLAUSE_NUM_THREADS:
10696 case OMP_CLAUSE_SCHEDULE:
10697 case OMP_CLAUSE_COLLAPSE:
10698 OMP_CLAUSE_OPERAND (nc, 0)
10699 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain,
10700 in_decl, /*integral_constant_expression_p=*/false);
10702 case OMP_CLAUSE_NOWAIT:
10703 case OMP_CLAUSE_ORDERED:
10704 case OMP_CLAUSE_DEFAULT:
10705 case OMP_CLAUSE_UNTIED:
10708 gcc_unreachable ();
10712 return finish_omp_clauses (nreverse (new_clauses));
10715 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */
10718 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain,
10721 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl)
10723 tree purpose, value, chain;
10728 if (TREE_CODE (t) != TREE_LIST)
10729 return tsubst_copy_and_build (t, args, complain, in_decl,
10730 /*function_p=*/false,
10731 /*integral_constant_expression_p=*/false);
10733 if (t == void_list_node)
10736 purpose = TREE_PURPOSE (t);
10738 purpose = RECUR (purpose);
10739 value = TREE_VALUE (t);
10741 value = RECUR (value);
10742 chain = TREE_CHAIN (t);
10743 if (chain && chain != void_type_node)
10744 chain = RECUR (chain);
10745 return tree_cons (purpose, value, chain);
10749 /* Substitute one OMP_FOR iterator. */
10752 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv,
10753 tree condv, tree incrv, tree *clauses,
10754 tree args, tsubst_flags_t complain, tree in_decl,
10755 bool integral_constant_expression_p)
10757 #define RECUR(NODE) \
10758 tsubst_expr ((NODE), args, complain, in_decl, \
10759 integral_constant_expression_p)
10760 tree decl, init, cond, incr, auto_node;
10762 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i);
10763 gcc_assert (TREE_CODE (init) == MODIFY_EXPR);
10764 decl = RECUR (TREE_OPERAND (init, 0));
10765 init = TREE_OPERAND (init, 1);
10766 auto_node = type_uses_auto (TREE_TYPE (decl));
10767 if (auto_node && init)
10769 tree init_expr = init;
10770 if (TREE_CODE (init_expr) == DECL_EXPR)
10771 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr));
10772 init_expr = RECUR (init_expr);
10774 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node);
10776 gcc_assert (!type_dependent_expression_p (decl));
10778 if (!CLASS_TYPE_P (TREE_TYPE (decl)))
10780 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i));
10781 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
10782 if (TREE_CODE (incr) == MODIFY_EXPR)
10783 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR,
10784 RECUR (TREE_OPERAND (incr, 1)),
10787 incr = RECUR (incr);
10788 TREE_VEC_ELT (declv, i) = decl;
10789 TREE_VEC_ELT (initv, i) = init;
10790 TREE_VEC_ELT (condv, i) = cond;
10791 TREE_VEC_ELT (incrv, i) = incr;
10795 if (init && TREE_CODE (init) != DECL_EXPR)
10798 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c))
10800 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE
10801 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE)
10802 && OMP_CLAUSE_DECL (c) == decl)
10804 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE
10805 && OMP_CLAUSE_DECL (c) == decl)
10806 error ("iteration variable %qD should not be firstprivate", decl);
10807 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION
10808 && OMP_CLAUSE_DECL (c) == decl)
10809 error ("iteration variable %qD should not be reduction", decl);
10813 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE);
10814 OMP_CLAUSE_DECL (c) = decl;
10815 c = finish_omp_clauses (c);
10818 OMP_CLAUSE_CHAIN (c) = *clauses;
10823 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i);
10824 if (COMPARISON_CLASS_P (cond))
10825 cond = build2 (TREE_CODE (cond), boolean_type_node,
10826 RECUR (TREE_OPERAND (cond, 0)),
10827 RECUR (TREE_OPERAND (cond, 1)));
10829 cond = RECUR (cond);
10830 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i);
10831 switch (TREE_CODE (incr))
10833 case PREINCREMENT_EXPR:
10834 case PREDECREMENT_EXPR:
10835 case POSTINCREMENT_EXPR:
10836 case POSTDECREMENT_EXPR:
10837 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl),
10838 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE);
10841 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
10842 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
10844 tree rhs = TREE_OPERAND (incr, 1);
10845 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
10846 RECUR (TREE_OPERAND (incr, 0)),
10847 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
10848 RECUR (TREE_OPERAND (rhs, 0)),
10849 RECUR (TREE_OPERAND (rhs, 1))));
10852 incr = RECUR (incr);
10855 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR
10856 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR)
10858 tree lhs = RECUR (TREE_OPERAND (incr, 0));
10859 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs,
10860 build2 (TREE_CODE (TREE_OPERAND (incr, 1)),
10861 TREE_TYPE (decl), lhs,
10862 RECUR (TREE_OPERAND (incr, 2))));
10864 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR
10865 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR
10866 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR)))
10868 tree rhs = TREE_OPERAND (incr, 2);
10869 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl),
10870 RECUR (TREE_OPERAND (incr, 0)),
10871 build2 (TREE_CODE (rhs), TREE_TYPE (decl),
10872 RECUR (TREE_OPERAND (rhs, 0)),
10873 RECUR (TREE_OPERAND (rhs, 1))));
10876 incr = RECUR (incr);
10879 incr = RECUR (incr);
10883 TREE_VEC_ELT (declv, i) = decl;
10884 TREE_VEC_ELT (initv, i) = init;
10885 TREE_VEC_ELT (condv, i) = cond;
10886 TREE_VEC_ELT (incrv, i) = incr;
10890 /* Like tsubst_copy for expressions, etc. but also does semantic
10894 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl,
10895 bool integral_constant_expression_p)
10897 #define RECUR(NODE) \
10898 tsubst_expr ((NODE), args, complain, in_decl, \
10899 integral_constant_expression_p)
10903 if (t == NULL_TREE || t == error_mark_node)
10906 if (EXPR_HAS_LOCATION (t))
10907 input_location = EXPR_LOCATION (t);
10908 if (STATEMENT_CODE_P (TREE_CODE (t)))
10909 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
10911 switch (TREE_CODE (t))
10913 case STATEMENT_LIST:
10915 tree_stmt_iterator i;
10916 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
10917 RECUR (tsi_stmt (i));
10921 case CTOR_INITIALIZER:
10922 finish_mem_initializers (tsubst_initializer_list
10923 (TREE_OPERAND (t, 0), args));
10927 finish_return_stmt (RECUR (TREE_OPERAND (t, 0)));
10931 tmp = RECUR (EXPR_STMT_EXPR (t));
10932 if (EXPR_STMT_STMT_EXPR_RESULT (t))
10933 finish_stmt_expr_expr (tmp, cur_stmt_expr);
10935 finish_expr_stmt (tmp);
10939 do_using_directive (RECUR (USING_STMT_NAMESPACE (t)));
10947 decl = DECL_EXPR_DECL (t);
10948 if (TREE_CODE (decl) == LABEL_DECL)
10949 finish_label_decl (DECL_NAME (decl));
10950 else if (TREE_CODE (decl) == USING_DECL)
10952 tree scope = USING_DECL_SCOPE (decl);
10953 tree name = DECL_NAME (decl);
10956 scope = RECUR (scope);
10957 decl = lookup_qualified_name (scope, name,
10958 /*is_type_p=*/false,
10959 /*complain=*/false);
10960 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
10961 qualified_name_lookup_error (scope, name, decl, input_location);
10963 do_local_using_decl (decl, scope, name);
10967 init = DECL_INITIAL (decl);
10968 decl = tsubst (decl, args, complain, in_decl);
10969 if (decl != error_mark_node)
10971 /* By marking the declaration as instantiated, we avoid
10972 trying to instantiate it. Since instantiate_decl can't
10973 handle local variables, and since we've already done
10974 all that needs to be done, that's the right thing to
10976 if (TREE_CODE (decl) == VAR_DECL)
10977 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
10978 if (TREE_CODE (decl) == VAR_DECL
10979 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
10980 /* Anonymous aggregates are a special case. */
10981 finish_anon_union (decl);
10984 maybe_push_decl (decl);
10985 if (TREE_CODE (decl) == VAR_DECL
10986 && DECL_PRETTY_FUNCTION_P (decl))
10988 /* For __PRETTY_FUNCTION__ we have to adjust the
10990 const char *const name
10991 = cxx_printable_name (current_function_decl, 2);
10992 init = cp_fname_init (name, &TREE_TYPE (decl));
10996 tree t = RECUR (init);
10999 /* If we had an initializer but it
11000 instantiated to nothing,
11001 value-initialize the object. This will
11002 only occur when the initializer was a
11003 pack expansion where the parameter packs
11004 used in that expansion were of length
11006 init = build_value_init (TREE_TYPE (decl));
11011 cp_finish_decl (decl, init, false, NULL_TREE, 0);
11016 /* A DECL_EXPR can also be used as an expression, in the condition
11017 clause of an if/for/while construct. */
11022 stmt = begin_for_stmt ();
11023 RECUR (FOR_INIT_STMT (t));
11024 finish_for_init_stmt (stmt);
11025 tmp = RECUR (FOR_COND (t));
11026 finish_for_cond (tmp, stmt);
11027 tmp = RECUR (FOR_EXPR (t));
11028 finish_for_expr (tmp, stmt);
11029 RECUR (FOR_BODY (t));
11030 finish_for_stmt (stmt);
11034 stmt = begin_while_stmt ();
11035 tmp = RECUR (WHILE_COND (t));
11036 finish_while_stmt_cond (tmp, stmt);
11037 RECUR (WHILE_BODY (t));
11038 finish_while_stmt (stmt);
11042 stmt = begin_do_stmt ();
11043 RECUR (DO_BODY (t));
11044 finish_do_body (stmt);
11045 tmp = RECUR (DO_COND (t));
11046 finish_do_stmt (tmp, stmt);
11050 stmt = begin_if_stmt ();
11051 tmp = RECUR (IF_COND (t));
11052 finish_if_stmt_cond (tmp, stmt);
11053 RECUR (THEN_CLAUSE (t));
11054 finish_then_clause (stmt);
11056 if (ELSE_CLAUSE (t))
11058 begin_else_clause (stmt);
11059 RECUR (ELSE_CLAUSE (t));
11060 finish_else_clause (stmt);
11063 finish_if_stmt (stmt);
11067 if (BIND_EXPR_BODY_BLOCK (t))
11068 stmt = begin_function_body ();
11070 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
11071 ? BCS_TRY_BLOCK : 0);
11073 RECUR (BIND_EXPR_BODY (t));
11075 if (BIND_EXPR_BODY_BLOCK (t))
11076 finish_function_body (stmt);
11078 finish_compound_stmt (stmt);
11082 finish_break_stmt ();
11085 case CONTINUE_STMT:
11086 finish_continue_stmt ();
11090 stmt = begin_switch_stmt ();
11091 tmp = RECUR (SWITCH_STMT_COND (t));
11092 finish_switch_cond (tmp, stmt);
11093 RECUR (SWITCH_STMT_BODY (t));
11094 finish_switch_stmt (stmt);
11097 case CASE_LABEL_EXPR:
11098 finish_case_label (EXPR_LOCATION (t),
11099 RECUR (CASE_LOW (t)),
11100 RECUR (CASE_HIGH (t)));
11105 tree decl = LABEL_EXPR_LABEL (t);
11108 label = finish_label_stmt (DECL_NAME (decl));
11109 if (DECL_ATTRIBUTES (decl) != NULL_TREE)
11110 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0);
11115 tmp = GOTO_DESTINATION (t);
11116 if (TREE_CODE (tmp) != LABEL_DECL)
11117 /* Computed goto's must be tsubst'd into. On the other hand,
11118 non-computed gotos must not be; the identifier in question
11119 will have no binding. */
11122 tmp = DECL_NAME (tmp);
11123 finish_goto_stmt (tmp);
11127 tmp = finish_asm_stmt
11128 (ASM_VOLATILE_P (t),
11129 RECUR (ASM_STRING (t)),
11130 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl),
11131 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl),
11132 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl));
11134 tree asm_expr = tmp;
11135 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
11136 asm_expr = TREE_OPERAND (asm_expr, 0);
11137 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
11144 stmt = begin_try_block ();
11145 RECUR (TRY_STMTS (t));
11146 finish_cleanup_try_block (stmt);
11147 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt);
11151 tree compound_stmt = NULL_TREE;
11153 if (FN_TRY_BLOCK_P (t))
11154 stmt = begin_function_try_block (&compound_stmt);
11156 stmt = begin_try_block ();
11158 RECUR (TRY_STMTS (t));
11160 if (FN_TRY_BLOCK_P (t))
11161 finish_function_try_block (stmt);
11163 finish_try_block (stmt);
11165 RECUR (TRY_HANDLERS (t));
11166 if (FN_TRY_BLOCK_P (t))
11167 finish_function_handler_sequence (stmt, compound_stmt);
11169 finish_handler_sequence (stmt);
11175 tree decl = HANDLER_PARMS (t);
11179 decl = tsubst (decl, args, complain, in_decl);
11180 /* Prevent instantiate_decl from trying to instantiate
11181 this variable. We've already done all that needs to be
11183 if (decl != error_mark_node)
11184 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
11186 stmt = begin_handler ();
11187 finish_handler_parms (decl, stmt);
11188 RECUR (HANDLER_BODY (t));
11189 finish_handler (stmt);
11194 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
11197 case STATIC_ASSERT:
11200 tsubst_expr (STATIC_ASSERT_CONDITION (t),
11203 /*integral_constant_expression_p=*/true);
11204 finish_static_assert (condition,
11205 STATIC_ASSERT_MESSAGE (t),
11206 STATIC_ASSERT_SOURCE_LOCATION (t),
11207 /*member_p=*/false);
11212 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t),
11213 args, complain, in_decl);
11214 stmt = begin_omp_parallel ();
11215 RECUR (OMP_PARALLEL_BODY (t));
11216 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt))
11217 = OMP_PARALLEL_COMBINED (t);
11221 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t),
11222 args, complain, in_decl);
11223 stmt = begin_omp_task ();
11224 RECUR (OMP_TASK_BODY (t));
11225 finish_omp_task (tmp, stmt);
11230 tree clauses, body, pre_body;
11231 tree declv, initv, condv, incrv;
11234 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t),
11235 args, complain, in_decl);
11236 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11237 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11238 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11239 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t)));
11241 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++)
11242 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv,
11243 &clauses, args, complain, in_decl,
11244 integral_constant_expression_p);
11246 stmt = begin_omp_structured_block ();
11248 for (i = 0; i < TREE_VEC_LENGTH (initv); i++)
11249 if (TREE_VEC_ELT (initv, i) == NULL
11250 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR)
11251 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i));
11252 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i))))
11254 tree init = RECUR (TREE_VEC_ELT (initv, i));
11255 gcc_assert (init == TREE_VEC_ELT (declv, i));
11256 TREE_VEC_ELT (initv, i) = NULL_TREE;
11260 tree decl_expr = TREE_VEC_ELT (initv, i);
11261 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr));
11262 gcc_assert (init != NULL);
11263 TREE_VEC_ELT (initv, i) = RECUR (init);
11264 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL;
11266 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init;
11269 pre_body = push_stmt_list ();
11270 RECUR (OMP_FOR_PRE_BODY (t));
11271 pre_body = pop_stmt_list (pre_body);
11273 body = push_stmt_list ();
11274 RECUR (OMP_FOR_BODY (t));
11275 body = pop_stmt_list (body);
11277 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv,
11278 body, pre_body, clauses);
11280 add_stmt (finish_omp_structured_block (stmt));
11286 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl);
11287 stmt = push_stmt_list ();
11288 RECUR (OMP_BODY (t));
11289 stmt = pop_stmt_list (stmt);
11292 OMP_BODY (t) = stmt;
11293 OMP_CLAUSES (t) = tmp;
11301 stmt = push_stmt_list ();
11302 RECUR (OMP_BODY (t));
11303 stmt = pop_stmt_list (stmt);
11306 OMP_BODY (t) = stmt;
11311 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t));
11313 tree op1 = TREE_OPERAND (t, 1);
11314 tree lhs = RECUR (TREE_OPERAND (op1, 0));
11315 tree rhs = RECUR (TREE_OPERAND (op1, 1));
11316 finish_omp_atomic (TREE_CODE (op1), lhs, rhs);
11320 case EXPR_PACK_EXPANSION:
11321 error ("invalid use of pack expansion expression");
11322 return error_mark_node;
11324 case NONTYPE_ARGUMENT_PACK:
11325 error ("use %<...%> to expand argument pack");
11326 return error_mark_node;
11329 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
11331 return tsubst_copy_and_build (t, args, complain, in_decl,
11332 /*function_p=*/false,
11333 integral_constant_expression_p);
11340 /* T is a postfix-expression that is not being used in a function
11341 call. Return the substituted version of T. */
11344 tsubst_non_call_postfix_expression (tree t, tree args,
11345 tsubst_flags_t complain,
11348 if (TREE_CODE (t) == SCOPE_REF)
11349 t = tsubst_qualified_id (t, args, complain, in_decl,
11350 /*done=*/false, /*address_p=*/false);
11352 t = tsubst_copy_and_build (t, args, complain, in_decl,
11353 /*function_p=*/false,
11354 /*integral_constant_expression_p=*/false);
11359 /* Like tsubst but deals with expressions and performs semantic
11360 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
11363 tsubst_copy_and_build (tree t,
11365 tsubst_flags_t complain,
11368 bool integral_constant_expression_p)
11370 #define RECUR(NODE) \
11371 tsubst_copy_and_build (NODE, args, complain, in_decl, \
11372 /*function_p=*/false, \
11373 integral_constant_expression_p)
11377 if (t == NULL_TREE || t == error_mark_node)
11380 switch (TREE_CODE (t))
11384 /* Fall through. */
11385 case IDENTIFIER_NODE:
11389 bool non_integral_constant_expression_p;
11390 const char *error_msg;
11392 if (IDENTIFIER_TYPENAME_P (t))
11394 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11395 t = mangle_conv_op_name_for_type (new_type);
11398 /* Look up the name. */
11399 decl = lookup_name (t);
11401 /* By convention, expressions use ERROR_MARK_NODE to indicate
11402 failure, not NULL_TREE. */
11403 if (decl == NULL_TREE)
11404 decl = error_mark_node;
11406 decl = finish_id_expression (t, decl, NULL_TREE,
11408 integral_constant_expression_p,
11409 /*allow_non_integral_constant_expression_p=*/false,
11410 &non_integral_constant_expression_p,
11411 /*template_p=*/false,
11413 /*address_p=*/false,
11414 /*template_arg_p=*/false,
11419 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
11420 decl = unqualified_name_lookup_error (decl);
11424 case TEMPLATE_ID_EXPR:
11427 tree templ = RECUR (TREE_OPERAND (t, 0));
11428 tree targs = TREE_OPERAND (t, 1);
11431 targs = tsubst_template_args (targs, args, complain, in_decl);
11433 if (TREE_CODE (templ) == COMPONENT_REF)
11435 object = TREE_OPERAND (templ, 0);
11436 templ = TREE_OPERAND (templ, 1);
11439 object = NULL_TREE;
11440 templ = lookup_template_function (templ, targs);
11443 return build3 (COMPONENT_REF, TREE_TYPE (templ),
11444 object, templ, NULL_TREE);
11446 return baselink_for_fns (templ);
11451 tree r = RECUR (TREE_OPERAND (t, 0));
11453 if (REFERENCE_REF_P (t))
11455 /* A type conversion to reference type will be enclosed in
11456 such an indirect ref, but the substitution of the cast
11457 will have also added such an indirect ref. */
11458 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
11459 r = convert_from_reference (r);
11462 r = build_x_indirect_ref (r, "unary *", complain);
11468 (tsubst (TREE_TYPE (t), args, complain, in_decl),
11469 RECUR (TREE_OPERAND (t, 0)));
11472 case REINTERPRET_CAST_EXPR:
11473 case CONST_CAST_EXPR:
11474 case DYNAMIC_CAST_EXPR:
11475 case STATIC_CAST_EXPR:
11480 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
11481 if (integral_constant_expression_p
11482 && !cast_valid_in_integral_constant_expression_p (type))
11484 if (complain & tf_error)
11485 error ("a cast to a type other than an integral or "
11486 "enumeration type cannot appear in a constant-expression");
11487 return error_mark_node;
11490 op = RECUR (TREE_OPERAND (t, 0));
11492 switch (TREE_CODE (t))
11495 return build_functional_cast (type, op, complain);
11496 case REINTERPRET_CAST_EXPR:
11497 return build_reinterpret_cast (type, op, complain);
11498 case CONST_CAST_EXPR:
11499 return build_const_cast (type, op, complain);
11500 case DYNAMIC_CAST_EXPR:
11501 return build_dynamic_cast (type, op, complain);
11502 case STATIC_CAST_EXPR:
11503 return build_static_cast (type, op, complain);
11505 gcc_unreachable ();
11509 case POSTDECREMENT_EXPR:
11510 case POSTINCREMENT_EXPR:
11511 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11512 args, complain, in_decl);
11513 return build_x_unary_op (TREE_CODE (t), op1, complain);
11515 case PREDECREMENT_EXPR:
11516 case PREINCREMENT_EXPR:
11520 case TRUTH_NOT_EXPR:
11521 case UNARY_PLUS_EXPR: /* Unary + */
11522 case REALPART_EXPR:
11523 case IMAGPART_EXPR:
11524 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)),
11528 op1 = TREE_OPERAND (t, 0);
11529 if (TREE_CODE (op1) == SCOPE_REF)
11530 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
11531 /*done=*/true, /*address_p=*/true);
11533 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
11535 if (TREE_CODE (op1) == LABEL_DECL)
11536 return finish_label_address_expr (DECL_NAME (op1),
11537 EXPR_LOCATION (op1));
11538 return build_x_unary_op (ADDR_EXPR, op1, complain);
11543 case TRUNC_DIV_EXPR:
11544 case CEIL_DIV_EXPR:
11545 case FLOOR_DIV_EXPR:
11546 case ROUND_DIV_EXPR:
11547 case EXACT_DIV_EXPR:
11551 case TRUNC_MOD_EXPR:
11552 case FLOOR_MOD_EXPR:
11553 case TRUTH_ANDIF_EXPR:
11554 case TRUTH_ORIF_EXPR:
11555 case TRUTH_AND_EXPR:
11556 case TRUTH_OR_EXPR:
11571 return build_x_binary_op
11573 RECUR (TREE_OPERAND (t, 0)),
11574 (TREE_NO_WARNING (TREE_OPERAND (t, 0))
11576 : TREE_CODE (TREE_OPERAND (t, 0))),
11577 RECUR (TREE_OPERAND (t, 1)),
11578 (TREE_NO_WARNING (TREE_OPERAND (t, 1))
11580 : TREE_CODE (TREE_OPERAND (t, 1))),
11581 /*overloaded_p=*/NULL,
11585 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
11586 /*address_p=*/false);
11588 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11589 args, complain, in_decl);
11590 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain);
11593 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0)))
11594 return tsubst_copy (t, args, complain, in_decl);
11598 op1 = TREE_OPERAND (t, 0);
11601 /* When there are no ARGS, we are trying to evaluate a
11602 non-dependent expression from the parser. Trying to do
11603 the substitutions may not work. */
11605 op1 = TREE_TYPE (op1);
11609 ++cp_unevaluated_operand;
11610 ++c_inhibit_evaluation_warnings;
11611 op1 = tsubst_copy_and_build (op1, args, complain, in_decl,
11612 /*function_p=*/false,
11613 /*integral_constant_expression_p=*/false);
11614 --cp_unevaluated_operand;
11615 --c_inhibit_evaluation_warnings;
11618 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t),
11619 complain & tf_error);
11621 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t),
11622 complain & tf_error);
11626 tree r = build_x_modify_expr
11627 (RECUR (TREE_OPERAND (t, 0)),
11628 TREE_CODE (TREE_OPERAND (t, 1)),
11629 RECUR (TREE_OPERAND (t, 2)),
11631 /* TREE_NO_WARNING must be set if either the expression was
11632 parenthesized or it uses an operator such as >>= rather
11633 than plain assignment. In the former case, it was already
11634 set and must be copied. In the latter case,
11635 build_x_modify_expr sets it and it must not be reset
11637 if (TREE_NO_WARNING (t))
11638 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
11643 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11644 args, complain, in_decl);
11645 /* Remember that there was a reference to this entity. */
11648 return build_x_arrow (op1);
11652 tree placement = RECUR (TREE_OPERAND (t, 0));
11653 tree init = RECUR (TREE_OPERAND (t, 3));
11654 VEC(tree,gc) *placement_vec;
11655 VEC(tree,gc) *init_vec;
11658 if (placement == NULL_TREE)
11659 placement_vec = NULL;
11662 placement_vec = make_tree_vector ();
11663 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement))
11664 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement));
11667 /* If there was an initializer in the original tree, but it
11668 instantiated to an empty list, then we should pass a
11669 non-NULL empty vector to tell build_new that it was an
11670 empty initializer() rather than no initializer. This can
11671 only happen when the initializer is a pack expansion whose
11672 parameter packs are of length zero. */
11673 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE)
11677 init_vec = make_tree_vector ();
11678 if (init == void_zero_node)
11679 gcc_assert (init_vec != NULL);
11682 for (; init != NULL_TREE; init = TREE_CHAIN (init))
11683 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init));
11687 ret = build_new (&placement_vec,
11688 RECUR (TREE_OPERAND (t, 1)),
11689 RECUR (TREE_OPERAND (t, 2)),
11691 NEW_EXPR_USE_GLOBAL (t),
11694 if (placement_vec != NULL)
11695 release_tree_vector (placement_vec);
11696 if (init_vec != NULL)
11697 release_tree_vector (init_vec);
11703 return delete_sanity
11704 (RECUR (TREE_OPERAND (t, 0)),
11705 RECUR (TREE_OPERAND (t, 1)),
11706 DELETE_EXPR_USE_VEC (t),
11707 DELETE_EXPR_USE_GLOBAL (t));
11709 case COMPOUND_EXPR:
11710 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
11711 RECUR (TREE_OPERAND (t, 1)),
11717 VEC(tree,gc) *call_args;
11718 unsigned int nargs, i;
11723 function = CALL_EXPR_FN (t);
11724 /* When we parsed the expression, we determined whether or
11725 not Koenig lookup should be performed. */
11726 koenig_p = KOENIG_LOOKUP_P (t);
11727 if (TREE_CODE (function) == SCOPE_REF)
11729 qualified_p = true;
11730 function = tsubst_qualified_id (function, args, complain, in_decl,
11732 /*address_p=*/false);
11736 if (TREE_CODE (function) == COMPONENT_REF)
11738 tree op = TREE_OPERAND (function, 1);
11740 qualified_p = (TREE_CODE (op) == SCOPE_REF
11741 || (BASELINK_P (op)
11742 && BASELINK_QUALIFIED_P (op)));
11745 qualified_p = false;
11747 function = tsubst_copy_and_build (function, args, complain,
11750 integral_constant_expression_p);
11752 if (BASELINK_P (function))
11753 qualified_p = true;
11756 nargs = call_expr_nargs (t);
11757 call_args = make_tree_vector ();
11758 for (i = 0; i < nargs; ++i)
11760 tree arg = CALL_EXPR_ARG (t, i);
11762 if (!PACK_EXPANSION_P (arg))
11763 VEC_safe_push (tree, gc, call_args,
11764 RECUR (CALL_EXPR_ARG (t, i)));
11767 /* Expand the pack expansion and push each entry onto
11769 arg = tsubst_pack_expansion (arg, args, complain, in_decl);
11770 if (TREE_CODE (arg) == TREE_VEC)
11772 unsigned int len, j;
11774 len = TREE_VEC_LENGTH (arg);
11775 for (j = 0; j < len; ++j)
11777 tree value = TREE_VEC_ELT (arg, j);
11778 if (value != NULL_TREE)
11779 value = convert_from_reference (value);
11780 VEC_safe_push (tree, gc, call_args, value);
11785 /* A partial substitution. Add one entry. */
11786 VEC_safe_push (tree, gc, call_args, arg);
11791 /* We do not perform argument-dependent lookup if normal
11792 lookup finds a non-function, in accordance with the
11793 expected resolution of DR 218. */
11795 && ((is_overloaded_fn (function)
11796 /* If lookup found a member function, the Koenig lookup is
11797 not appropriate, even if an unqualified-name was used
11798 to denote the function. */
11799 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
11800 || TREE_CODE (function) == IDENTIFIER_NODE)
11801 /* Only do this when substitution turns a dependent call
11802 into a non-dependent call. */
11803 && type_dependent_expression_p_push (t)
11804 && !any_type_dependent_arguments_p (call_args))
11805 function = perform_koenig_lookup (function, call_args);
11807 if (TREE_CODE (function) == IDENTIFIER_NODE)
11809 unqualified_name_lookup_error (function);
11810 release_tree_vector (call_args);
11811 return error_mark_node;
11814 /* Remember that there was a reference to this entity. */
11815 if (DECL_P (function))
11816 mark_used (function);
11818 if (TREE_CODE (function) == OFFSET_REF)
11819 ret = build_offset_ref_call_from_tree (function, &call_args);
11820 else if (TREE_CODE (function) == COMPONENT_REF)
11822 if (!BASELINK_P (TREE_OPERAND (function, 1)))
11823 ret = finish_call_expr (function, &call_args,
11824 /*disallow_virtual=*/false,
11825 /*koenig_p=*/false,
11828 ret = (build_new_method_call
11829 (TREE_OPERAND (function, 0),
11830 TREE_OPERAND (function, 1),
11831 &call_args, NULL_TREE,
11832 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL,
11837 ret = finish_call_expr (function, &call_args,
11838 /*disallow_virtual=*/qualified_p,
11842 release_tree_vector (call_args);
11848 return build_x_conditional_expr
11849 (RECUR (TREE_OPERAND (t, 0)),
11850 RECUR (TREE_OPERAND (t, 1)),
11851 RECUR (TREE_OPERAND (t, 2)),
11854 case PSEUDO_DTOR_EXPR:
11855 return finish_pseudo_destructor_expr
11856 (RECUR (TREE_OPERAND (t, 0)),
11857 RECUR (TREE_OPERAND (t, 1)),
11858 RECUR (TREE_OPERAND (t, 2)));
11862 tree purpose, value, chain;
11864 if (t == void_list_node)
11867 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t)))
11868 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t))))
11870 /* We have pack expansions, so expand those and
11871 create a new list out of it. */
11872 tree purposevec = NULL_TREE;
11873 tree valuevec = NULL_TREE;
11877 /* Expand the argument expressions. */
11878 if (TREE_PURPOSE (t))
11879 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args,
11880 complain, in_decl);
11881 if (TREE_VALUE (t))
11882 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args,
11883 complain, in_decl);
11885 /* Build the rest of the list. */
11886 chain = TREE_CHAIN (t);
11887 if (chain && chain != void_type_node)
11888 chain = RECUR (chain);
11890 /* Determine the number of arguments. */
11891 if (purposevec && TREE_CODE (purposevec) == TREE_VEC)
11893 len = TREE_VEC_LENGTH (purposevec);
11894 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec));
11896 else if (TREE_CODE (valuevec) == TREE_VEC)
11897 len = TREE_VEC_LENGTH (valuevec);
11900 /* Since we only performed a partial substitution into
11901 the argument pack, we only return a single list
11903 if (purposevec == TREE_PURPOSE (t)
11904 && valuevec == TREE_VALUE (t)
11905 && chain == TREE_CHAIN (t))
11908 return tree_cons (purposevec, valuevec, chain);
11911 /* Convert the argument vectors into a TREE_LIST */
11915 /* Grab the Ith values. */
11917 purpose = purposevec ? TREE_VEC_ELT (purposevec, i)
11920 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i))
11923 /* Build the list (backwards). */
11924 chain = tree_cons (purpose, value, chain);
11930 purpose = TREE_PURPOSE (t);
11932 purpose = RECUR (purpose);
11933 value = TREE_VALUE (t);
11935 value = RECUR (value);
11936 chain = TREE_CHAIN (t);
11937 if (chain && chain != void_type_node)
11938 chain = RECUR (chain);
11939 if (purpose == TREE_PURPOSE (t)
11940 && value == TREE_VALUE (t)
11941 && chain == TREE_CHAIN (t))
11943 return tree_cons (purpose, value, chain);
11946 case COMPONENT_REF:
11952 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
11953 args, complain, in_decl);
11954 /* Remember that there was a reference to this entity. */
11955 if (DECL_P (object))
11956 mark_used (object);
11957 object_type = TREE_TYPE (object);
11959 member = TREE_OPERAND (t, 1);
11960 if (BASELINK_P (member))
11961 member = tsubst_baselink (member,
11962 non_reference (TREE_TYPE (object)),
11963 args, complain, in_decl);
11965 member = tsubst_copy (member, args, complain, in_decl);
11966 if (member == error_mark_node)
11967 return error_mark_node;
11969 if (object_type && !CLASS_TYPE_P (object_type))
11971 if (SCALAR_TYPE_P (object_type))
11973 tree s = NULL_TREE;
11974 tree dtor = member;
11976 if (TREE_CODE (dtor) == SCOPE_REF)
11978 s = TREE_OPERAND (dtor, 0);
11979 dtor = TREE_OPERAND (dtor, 1);
11981 if (TREE_CODE (dtor) == BIT_NOT_EXPR)
11983 dtor = TREE_OPERAND (dtor, 0);
11985 return finish_pseudo_destructor_expr (object, s, dtor);
11989 else if (TREE_CODE (member) == SCOPE_REF
11990 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
11995 /* Lookup the template functions now that we know what the
11997 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
11998 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
11999 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
12000 /*is_type_p=*/false,
12001 /*complain=*/false);
12002 if (BASELINK_P (member))
12004 BASELINK_FUNCTIONS (member)
12005 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
12007 member = (adjust_result_of_qualified_name_lookup
12008 (member, BINFO_TYPE (BASELINK_BINFO (member)),
12013 qualified_name_lookup_error (object_type, tmpl, member,
12015 return error_mark_node;
12018 else if (TREE_CODE (member) == SCOPE_REF
12019 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
12020 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
12022 if (complain & tf_error)
12024 if (TYPE_P (TREE_OPERAND (member, 0)))
12025 error ("%qT is not a class or namespace",
12026 TREE_OPERAND (member, 0));
12028 error ("%qD is not a class or namespace",
12029 TREE_OPERAND (member, 0));
12031 return error_mark_node;
12033 else if (TREE_CODE (member) == FIELD_DECL)
12034 return finish_non_static_data_member (member, object, NULL_TREE);
12036 return finish_class_member_access_expr (object, member,
12037 /*template_p=*/false,
12043 (RECUR (TREE_OPERAND (t, 0)));
12047 VEC(constructor_elt,gc) *n;
12048 constructor_elt *ce;
12049 unsigned HOST_WIDE_INT idx;
12050 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
12051 bool process_index_p;
12053 bool need_copy_p = false;
12056 if (type == error_mark_node)
12057 return error_mark_node;
12059 /* digest_init will do the wrong thing if we let it. */
12060 if (type && TYPE_PTRMEMFUNC_P (type))
12063 /* We do not want to process the index of aggregate
12064 initializers as they are identifier nodes which will be
12065 looked up by digest_init. */
12066 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type));
12068 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
12069 newlen = VEC_length (constructor_elt, n);
12070 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
12072 if (ce->index && process_index_p)
12073 ce->index = RECUR (ce->index);
12075 if (PACK_EXPANSION_P (ce->value))
12077 /* Substitute into the pack expansion. */
12078 ce->value = tsubst_pack_expansion (ce->value, args, complain,
12081 if (ce->value == error_mark_node)
12083 else if (TREE_VEC_LENGTH (ce->value) == 1)
12084 /* Just move the argument into place. */
12085 ce->value = TREE_VEC_ELT (ce->value, 0);
12088 /* Update the length of the final CONSTRUCTOR
12089 arguments vector, and note that we will need to
12091 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1;
12092 need_copy_p = true;
12096 ce->value = RECUR (ce->value);
12101 VEC(constructor_elt,gc) *old_n = n;
12103 n = VEC_alloc (constructor_elt, gc, newlen);
12104 for (idx = 0; VEC_iterate (constructor_elt, old_n, idx, ce);
12107 if (TREE_CODE (ce->value) == TREE_VEC)
12109 int i, len = TREE_VEC_LENGTH (ce->value);
12110 for (i = 0; i < len; ++i)
12111 CONSTRUCTOR_APPEND_ELT (n, 0,
12112 TREE_VEC_ELT (ce->value, i));
12115 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value);
12119 r = build_constructor (init_list_type_node, n);
12120 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t);
12122 if (TREE_HAS_CONSTRUCTOR (t))
12123 return finish_compound_literal (type, r);
12130 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
12131 if (TYPE_P (operand_0))
12132 return get_typeid (operand_0);
12133 return build_typeid (operand_0);
12143 tree r = tsubst_copy (t, args, complain, in_decl);
12145 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
12146 /* If the original type was a reference, we'll be wrapped in
12147 the appropriate INDIRECT_REF. */
12148 r = convert_from_reference (r);
12153 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
12154 tsubst_copy (TREE_TYPE (t), args, complain,
12157 case OFFSETOF_EXPR:
12158 return finish_offsetof (RECUR (TREE_OPERAND (t, 0)));
12162 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args,
12163 complain, in_decl);
12165 tree type2 = TRAIT_EXPR_TYPE2 (t);
12167 type2 = tsubst_copy (type2, args, complain, in_decl);
12169 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2);
12174 tree old_stmt_expr = cur_stmt_expr;
12175 tree stmt_expr = begin_stmt_expr ();
12177 cur_stmt_expr = stmt_expr;
12178 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl,
12179 integral_constant_expression_p);
12180 stmt_expr = finish_stmt_expr (stmt_expr, false);
12181 cur_stmt_expr = old_stmt_expr;
12187 t = tsubst_copy (t, args, complain, in_decl);
12188 /* As in finish_id_expression, we resolve enumeration constants
12189 to their underlying values. */
12190 if (TREE_CODE (t) == CONST_DECL)
12192 used_types_insert (TREE_TYPE (t));
12193 return DECL_INITIAL (t);
12198 /* Handle Objective-C++ constructs, if appropriate. */
12201 = objcp_tsubst_copy_and_build (t, args, complain,
12202 in_decl, /*function_p=*/false);
12206 return tsubst_copy (t, args, complain, in_decl);
12212 /* Verify that the instantiated ARGS are valid. For type arguments,
12213 make sure that the type's linkage is ok. For non-type arguments,
12214 make sure they are constants if they are integral or enumerations.
12215 Emit an error under control of COMPLAIN, and return TRUE on error. */
12218 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain)
12220 if (ARGUMENT_PACK_P (t))
12222 tree vec = ARGUMENT_PACK_ARGS (t);
12223 int len = TREE_VEC_LENGTH (vec);
12224 bool result = false;
12227 for (i = 0; i < len; ++i)
12228 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain))
12232 else if (TYPE_P (t))
12234 /* [basic.link]: A name with no linkage (notably, the name
12235 of a class or enumeration declared in a local scope)
12236 shall not be used to declare an entity with linkage.
12237 This implies that names with no linkage cannot be used as
12238 template arguments. */
12239 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
12243 /* DR 488 makes use of a type with no linkage cause
12244 type deduction to fail. */
12245 if (complain & tf_error)
12247 if (TYPE_ANONYMOUS_P (nt))
12248 error ("%qT is/uses anonymous type", t);
12250 error ("template argument for %qD uses local type %qT",
12255 /* In order to avoid all sorts of complications, we do not
12256 allow variably-modified types as template arguments. */
12257 else if (variably_modified_type_p (t, NULL_TREE))
12259 if (complain & tf_error)
12260 error ("%qT is a variably modified type", t);
12264 /* A non-type argument of integral or enumerated type must be a
12266 else if (TREE_TYPE (t)
12267 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
12268 && !TREE_CONSTANT (t))
12270 if (complain & tf_error)
12271 error ("integral expression %qE is not constant", t);
12278 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
12280 int ix, len = DECL_NTPARMS (tmpl);
12281 bool result = false;
12283 for (ix = 0; ix != len; ix++)
12285 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain))
12288 if (result && (complain & tf_error))
12289 error (" trying to instantiate %qD", tmpl);
12293 /* Instantiate the indicated variable or function template TMPL with
12294 the template arguments in TARG_PTR. */
12297 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain)
12299 tree targ_ptr = orig_args;
12303 HOST_WIDE_INT saved_processing_template_decl;
12305 if (tmpl == error_mark_node)
12306 return error_mark_node;
12308 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
12310 /* If this function is a clone, handle it specially. */
12311 if (DECL_CLONED_FUNCTION_P (tmpl))
12316 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have
12317 DECL_CLONED_FUNCTION. */
12318 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl),
12319 targ_ptr, complain);
12320 if (spec == error_mark_node)
12321 return error_mark_node;
12323 /* Look for the clone. */
12324 FOR_EACH_CLONE (clone, spec)
12325 if (DECL_NAME (clone) == DECL_NAME (tmpl))
12327 /* We should always have found the clone by now. */
12328 gcc_unreachable ();
12332 /* Check to see if we already have this specialization. */
12333 gen_tmpl = most_general_template (tmpl);
12334 if (tmpl != gen_tmpl)
12335 /* The TMPL is a partial instantiation. To get a full set of
12336 arguments we must add the arguments used to perform the
12337 partial instantiation. */
12338 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
12341 /* It would be nice to avoid hashing here and then again in tsubst_decl,
12342 but it doesn't seem to be on the hot path. */
12343 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0);
12345 gcc_assert (tmpl == gen_tmpl
12346 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0))
12348 || fndecl == NULL_TREE);
12350 if (spec != NULL_TREE)
12353 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
12355 return error_mark_node;
12357 /* We are building a FUNCTION_DECL, during which the access of its
12358 parameters and return types have to be checked. However this
12359 FUNCTION_DECL which is the desired context for access checking
12360 is not built yet. We solve this chicken-and-egg problem by
12361 deferring all checks until we have the FUNCTION_DECL. */
12362 push_deferring_access_checks (dk_deferred);
12364 /* Although PROCESSING_TEMPLATE_DECL may be true at this point
12365 (because, for example, we have encountered a non-dependent
12366 function call in the body of a template function and must now
12367 determine which of several overloaded functions will be called),
12368 within the instantiation itself we are not processing a
12370 saved_processing_template_decl = processing_template_decl;
12371 processing_template_decl = 0;
12372 /* Substitute template parameters to obtain the specialization. */
12373 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
12374 targ_ptr, complain, gen_tmpl);
12375 processing_template_decl = saved_processing_template_decl;
12376 if (fndecl == error_mark_node)
12377 return error_mark_node;
12379 /* Now we know the specialization, compute access previously
12381 push_access_scope (fndecl);
12383 /* Some typedefs referenced from within the template code need to be access
12384 checked at template instantiation time, i.e now. These types were
12385 added to the template at parsing time. Let's get those and perfom
12386 the acces checks then. */
12387 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr);
12388 perform_deferred_access_checks ();
12389 pop_access_scope (fndecl);
12390 pop_deferring_access_checks ();
12392 /* The DECL_TI_TEMPLATE should always be the immediate parent
12393 template, not the most general template. */
12394 DECL_TI_TEMPLATE (fndecl) = tmpl;
12396 /* If we've just instantiated the main entry point for a function,
12397 instantiate all the alternate entry points as well. We do this
12398 by cloning the instantiation of the main entry point, not by
12399 instantiating the template clones. */
12400 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
12401 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
12406 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with
12407 NARGS elements of the arguments that are being used when calling
12408 it. TARGS is a vector into which the deduced template arguments
12411 Return zero for success, 2 for an incomplete match that doesn't resolve
12412 all the types, and 1 for complete failure. An error message will be
12413 printed only for an incomplete match.
12415 If FN is a conversion operator, or we are trying to produce a specific
12416 specialization, RETURN_TYPE is the return type desired.
12418 The EXPLICIT_TARGS are explicit template arguments provided via a
12421 The parameter STRICT is one of:
12424 We are deducing arguments for a function call, as in
12425 [temp.deduct.call].
12428 We are deducing arguments for a conversion function, as in
12429 [temp.deduct.conv].
12432 We are deducing arguments when doing an explicit instantiation
12433 as in [temp.explicit], when determining an explicit specialization
12434 as in [temp.expl.spec], or when taking the address of a function
12435 template, as in [temp.deduct.funcaddr]. */
12438 fn_type_unification (tree fn,
12439 tree explicit_targs,
12442 unsigned int nargs,
12444 unification_kind_t strict,
12450 bool incomplete_argument_packs_p = false;
12452 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
12454 fntype = TREE_TYPE (fn);
12455 if (explicit_targs)
12459 The specified template arguments must match the template
12460 parameters in kind (i.e., type, nontype, template), and there
12461 must not be more arguments than there are parameters;
12462 otherwise type deduction fails.
12464 Nontype arguments must match the types of the corresponding
12465 nontype template parameters, or must be convertible to the
12466 types of the corresponding nontype parameters as specified in
12467 _temp.arg.nontype_, otherwise type deduction fails.
12469 All references in the function type of the function template
12470 to the corresponding template parameters are replaced by the
12471 specified template argument values. If a substitution in a
12472 template parameter or in the function type of the function
12473 template results in an invalid type, type deduction fails. */
12474 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn);
12475 int i, len = TREE_VEC_LENGTH (tparms);
12476 tree converted_args;
12477 bool incomplete = false;
12479 if (explicit_targs == error_mark_node)
12483 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, tf_none,
12484 /*require_all_args=*/false,
12485 /*use_default_args=*/false));
12486 if (converted_args == error_mark_node)
12489 /* Substitute the explicit args into the function type. This is
12490 necessary so that, for instance, explicitly declared function
12491 arguments can match null pointed constants. If we were given
12492 an incomplete set of explicit args, we must not do semantic
12493 processing during substitution as we could create partial
12495 for (i = 0; i < len; i++)
12497 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
12498 bool parameter_pack = false;
12500 /* Dig out the actual parm. */
12501 if (TREE_CODE (parm) == TYPE_DECL
12502 || TREE_CODE (parm) == TEMPLATE_DECL)
12504 parm = TREE_TYPE (parm);
12505 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm);
12507 else if (TREE_CODE (parm) == PARM_DECL)
12509 parm = DECL_INITIAL (parm);
12510 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm);
12513 if (parameter_pack)
12517 template_parm_level_and_index (parm, &level, &idx);
12519 /* Mark the argument pack as "incomplete". We could
12520 still deduce more arguments during unification. */
12521 targ = TMPL_ARG (converted_args, level, idx);
12524 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1;
12525 ARGUMENT_PACK_EXPLICIT_ARGS (targ)
12526 = ARGUMENT_PACK_ARGS (targ);
12529 /* We have some incomplete argument packs. */
12530 incomplete_argument_packs_p = true;
12534 if (incomplete_argument_packs_p)
12535 /* Any substitution is guaranteed to be incomplete if there
12536 are incomplete argument packs, because we can still deduce
12540 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
12542 processing_template_decl += incomplete;
12543 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
12544 processing_template_decl -= incomplete;
12546 if (fntype == error_mark_node)
12549 /* Place the explicitly specified arguments in TARGS. */
12550 for (i = NUM_TMPL_ARGS (converted_args); i--;)
12551 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
12554 /* Never do unification on the 'this' parameter. */
12555 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype));
12561 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
12562 new_args = XALLOCAVEC (tree, nargs + 1);
12563 new_args[0] = return_type;
12564 memcpy (new_args + 1, args, nargs * sizeof (tree));
12569 /* We allow incomplete unification without an error message here
12570 because the standard doesn't seem to explicitly prohibit it. Our
12571 callers must be ready to deal with unification failures in any
12573 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
12574 targs, parms, args, nargs, /*subr=*/0,
12577 if (result == 0 && incomplete_argument_packs_p)
12579 int i, len = NUM_TMPL_ARGS (targs);
12581 /* Clear the "incomplete" flags on all argument packs. */
12582 for (i = 0; i < len; i++)
12584 tree arg = TREE_VEC_ELT (targs, i);
12585 if (ARGUMENT_PACK_P (arg))
12587 ARGUMENT_PACK_INCOMPLETE_P (arg) = 0;
12588 ARGUMENT_PACK_EXPLICIT_ARGS (arg) = NULL_TREE;
12593 /* Now that we have bindings for all of the template arguments,
12594 ensure that the arguments deduced for the template template
12595 parameters have compatible template parameter lists. We cannot
12596 check this property before we have deduced all template
12597 arguments, because the template parameter types of a template
12598 template parameter might depend on prior template parameters
12599 deduced after the template template parameter. The following
12600 ill-formed example illustrates this issue:
12602 template<typename T, template<T> class C> void f(C<5>, T);
12604 template<int N> struct X {};
12607 f(X<5>(), 5l); // error: template argument deduction fails
12610 The template parameter list of 'C' depends on the template type
12611 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to
12612 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the
12613 time that we deduce 'C'. */
12615 && !template_template_parm_bindings_ok_p
12616 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs))
12620 /* All is well so far. Now, check:
12624 When all template arguments have been deduced, all uses of
12625 template parameters in nondeduced contexts are replaced with
12626 the corresponding deduced argument values. If the
12627 substitution results in an invalid type, as described above,
12628 type deduction fails. */
12630 tree substed = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE);
12631 if (substed == error_mark_node)
12634 /* If we're looking for an exact match, check that what we got
12635 is indeed an exact match. It might not be if some template
12636 parameters are used in non-deduced contexts. */
12637 if (strict == DEDUCE_EXACT)
12642 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed));
12644 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg);
12645 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg))
12646 if (!same_type_p (args[i], TREE_VALUE (sarg)))
12654 /* Adjust types before performing type deduction, as described in
12655 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
12656 sections are symmetric. PARM is the type of a function parameter
12657 or the return type of the conversion function. ARG is the type of
12658 the argument passed to the call, or the type of the value
12659 initialized with the result of the conversion function.
12660 ARG_EXPR is the original argument expression, which may be null. */
12663 maybe_adjust_types_for_deduction (unification_kind_t strict,
12677 /* Swap PARM and ARG throughout the remainder of this
12678 function; the handling is precisely symmetric since PARM
12679 will initialize ARG rather than vice versa. */
12687 /* There is nothing to do in this case. */
12691 gcc_unreachable ();
12694 if (TREE_CODE (*parm) != REFERENCE_TYPE)
12696 /* [temp.deduct.call]
12698 If P is not a reference type:
12700 --If A is an array type, the pointer type produced by the
12701 array-to-pointer standard conversion (_conv.array_) is
12702 used in place of A for type deduction; otherwise,
12704 --If A is a function type, the pointer type produced by
12705 the function-to-pointer standard conversion
12706 (_conv.func_) is used in place of A for type deduction;
12709 --If A is a cv-qualified type, the top level
12710 cv-qualifiers of A's type are ignored for type
12712 if (TREE_CODE (*arg) == ARRAY_TYPE)
12713 *arg = build_pointer_type (TREE_TYPE (*arg));
12714 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
12715 *arg = build_pointer_type (*arg);
12717 *arg = TYPE_MAIN_VARIANT (*arg);
12720 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is
12721 of the form T&&, where T is a template parameter, and the argument
12722 is an lvalue, T is deduced as A& */
12723 if (TREE_CODE (*parm) == REFERENCE_TYPE
12724 && TYPE_REF_IS_RVALUE (*parm)
12725 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM
12726 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED
12727 && arg_expr && real_lvalue_p (arg_expr))
12728 *arg = build_reference_type (*arg);
12730 /* [temp.deduct.call]
12732 If P is a cv-qualified type, the top level cv-qualifiers
12733 of P's type are ignored for type deduction. If P is a
12734 reference type, the type referred to by P is used for
12736 *parm = TYPE_MAIN_VARIANT (*parm);
12737 if (TREE_CODE (*parm) == REFERENCE_TYPE)
12739 *parm = TREE_TYPE (*parm);
12740 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
12743 /* DR 322. For conversion deduction, remove a reference type on parm
12744 too (which has been swapped into ARG). */
12745 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
12746 *arg = TREE_TYPE (*arg);
12751 /* Most parms like fn_type_unification.
12753 If SUBR is 1, we're being called recursively (to unify the
12754 arguments of a function or method parameter of a function
12758 type_unification_real (tree tparms,
12762 unsigned int xnargs,
12764 unification_kind_t strict,
12767 tree parm, arg, arg_expr;
12769 int ntparms = TREE_VEC_LENGTH (tparms);
12771 int saw_undeduced = 0;
12774 unsigned int nargs;
12777 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
12778 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
12779 gcc_assert (ntparms > 0);
12784 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
12785 | UNIFY_ALLOW_DERIVED);
12789 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
12793 sub_strict = UNIFY_ALLOW_NONE;
12797 gcc_unreachable ();
12806 while (parms && parms != void_list_node
12809 if (TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
12812 parm = TREE_VALUE (parms);
12813 parms = TREE_CHAIN (parms);
12818 if (arg == error_mark_node)
12820 if (arg == unknown_type_node)
12821 /* We can't deduce anything from this, but we might get all the
12822 template args from other function args. */
12825 /* Conversions will be performed on a function argument that
12826 corresponds with a function parameter that contains only
12827 non-deducible template parameters and explicitly specified
12828 template parameters. */
12829 if (!uses_template_parms (parm))
12834 type = TREE_TYPE (arg);
12838 if (same_type_p (parm, type))
12840 if (strict != DEDUCE_EXACT
12841 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
12850 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
12851 if (type_unknown_p (arg))
12853 /* [temp.deduct.type]
12855 A template-argument can be deduced from a pointer to
12856 function or pointer to member function argument if
12857 the set of overloaded functions does not contain
12858 function templates and at most one of a set of
12859 overloaded functions provides a unique match. */
12860 if (resolve_overloaded_unification
12861 (tparms, targs, parm, arg, strict, sub_strict))
12867 arg = unlowered_expr_type (arg);
12868 if (arg == error_mark_node)
12873 int arg_strict = sub_strict;
12876 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg,
12879 if (arg == init_list_type_node && arg_expr)
12881 if (unify (tparms, targs, parm, arg, arg_strict))
12888 && parms != void_list_node
12889 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION)
12891 /* Unify the remaining arguments with the pack expansion type. */
12893 tree parmvec = make_tree_vec (1);
12895 /* Allocate a TREE_VEC and copy in all of the arguments */
12896 argvec = make_tree_vec (nargs - ia);
12897 for (i = 0; ia < nargs; ++ia, ++i)
12898 TREE_VEC_ELT (argvec, i) = args[ia];
12900 /* Copy the parameter into parmvec. */
12901 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms);
12902 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict,
12903 /*call_args_p=*/true, /*subr=*/subr))
12906 /* Advance to the end of the list of parameters. */
12907 parms = TREE_CHAIN (parms);
12910 /* Fail if we've reached the end of the parm list, and more args
12911 are present, and the parm list isn't variadic. */
12912 if (ia < nargs && parms == void_list_node)
12914 /* Fail if parms are left and they don't have default values. */
12915 if (parms && parms != void_list_node
12916 && TREE_PURPOSE (parms) == NULL_TREE)
12920 for (i = 0; i < ntparms; i++)
12921 if (!TREE_VEC_ELT (targs, i))
12925 if (TREE_VEC_ELT (tparms, i) == error_mark_node)
12928 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
12930 /* If this is an undeduced nontype parameter that depends on
12931 a type parameter, try another pass; its type may have been
12932 deduced from a later argument than the one from which
12933 this parameter can be deduced. */
12934 if (TREE_CODE (tparm) == PARM_DECL
12935 && uses_template_parms (TREE_TYPE (tparm))
12936 && !saw_undeduced++)
12939 /* Core issue #226 (C++0x) [temp.deduct]:
12941 If a template argument has not been deduced, its
12942 default template argument, if any, is used.
12944 When we are in C++98 mode, TREE_PURPOSE will either
12945 be NULL_TREE or ERROR_MARK_NODE, so we do not need
12946 to explicitly check cxx_dialect here. */
12947 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)))
12949 tree arg = tsubst (TREE_PURPOSE (TREE_VEC_ELT (tparms, i)),
12950 targs, tf_none, NULL_TREE);
12951 if (arg == error_mark_node)
12955 TREE_VEC_ELT (targs, i) = arg;
12960 /* If the type parameter is a parameter pack, then it will
12961 be deduced to an empty parameter pack. */
12962 if (template_parameter_pack_p (tparm))
12966 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX)
12968 arg = make_node (NONTYPE_ARGUMENT_PACK);
12969 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm));
12970 TREE_CONSTANT (arg) = 1;
12973 arg = make_node (TYPE_ARGUMENT_PACK);
12975 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0));
12977 TREE_VEC_ELT (targs, i) = arg;
12987 /* Subroutine of type_unification_real. Args are like the variables
12988 at the call site. ARG is an overloaded function (or template-id);
12989 we try deducing template args from each of the overloads, and if
12990 only one succeeds, we go with that. Modifies TARGS and returns
12991 true on success. */
12994 resolve_overloaded_unification (tree tparms,
12998 unification_kind_t strict,
13001 tree tempargs = copy_node (targs);
13003 tree goodfn = NULL_TREE;
13006 if (TREE_CODE (arg) == ADDR_EXPR)
13008 arg = TREE_OPERAND (arg, 0);
13014 if (TREE_CODE (arg) == COMPONENT_REF)
13015 /* Handle `&x' where `x' is some static or non-static member
13017 arg = TREE_OPERAND (arg, 1);
13019 if (TREE_CODE (arg) == OFFSET_REF)
13020 arg = TREE_OPERAND (arg, 1);
13022 /* Strip baselink information. */
13023 if (BASELINK_P (arg))
13024 arg = BASELINK_FUNCTIONS (arg);
13026 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
13028 /* If we got some explicit template args, we need to plug them into
13029 the affected templates before we try to unify, in case the
13030 explicit args will completely resolve the templates in question. */
13032 tree expl_subargs = TREE_OPERAND (arg, 1);
13033 arg = TREE_OPERAND (arg, 0);
13035 for (; arg; arg = OVL_NEXT (arg))
13037 tree fn = OVL_CURRENT (arg);
13038 tree subargs, elem;
13040 if (TREE_CODE (fn) != TEMPLATE_DECL)
13043 ++processing_template_decl;
13044 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
13045 expl_subargs, /*check_ret=*/false);
13048 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
13049 if (try_one_overload (tparms, targs, tempargs, parm,
13050 elem, strict, sub_strict, addr_p)
13051 && (!goodfn || !decls_match (goodfn, elem)))
13057 --processing_template_decl;
13060 else if (TREE_CODE (arg) != OVERLOAD
13061 && TREE_CODE (arg) != FUNCTION_DECL)
13062 /* If ARG is, for example, "(0, &f)" then its type will be unknown
13063 -- but the deduction does not succeed because the expression is
13064 not just the function on its own. */
13067 for (; arg; arg = OVL_NEXT (arg))
13068 if (try_one_overload (tparms, targs, tempargs, parm,
13069 TREE_TYPE (OVL_CURRENT (arg)),
13070 strict, sub_strict, addr_p)
13071 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg))))
13073 goodfn = OVL_CURRENT (arg);
13077 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13078 to function or pointer to member function argument if the set of
13079 overloaded functions does not contain function templates and at most
13080 one of a set of overloaded functions provides a unique match.
13082 So if we found multiple possibilities, we return success but don't
13083 deduce anything. */
13087 int i = TREE_VEC_LENGTH (targs);
13089 if (TREE_VEC_ELT (tempargs, i))
13090 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
13098 /* Subroutine of resolve_overloaded_unification; does deduction for a single
13099 overload. Fills TARGS with any deduced arguments, or error_mark_node if
13100 different overloads deduce different arguments for a given parm.
13101 ADDR_P is true if the expression for which deduction is being
13102 performed was of the form "& fn" rather than simply "fn".
13104 Returns 1 on success. */
13107 try_one_overload (tree tparms,
13112 unification_kind_t strict,
13120 /* [temp.deduct.type] A template-argument can be deduced from a pointer
13121 to function or pointer to member function argument if the set of
13122 overloaded functions does not contain function templates and at most
13123 one of a set of overloaded functions provides a unique match.
13125 So if this is a template, just return success. */
13127 if (uses_template_parms (arg))
13130 if (TREE_CODE (arg) == METHOD_TYPE)
13131 arg = build_ptrmemfunc_type (build_pointer_type (arg));
13133 arg = build_pointer_type (arg);
13135 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL);
13137 /* We don't copy orig_targs for this because if we have already deduced
13138 some template args from previous args, unify would complain when we
13139 try to deduce a template parameter for the same argument, even though
13140 there isn't really a conflict. */
13141 nargs = TREE_VEC_LENGTH (targs);
13142 tempargs = make_tree_vec (nargs);
13144 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
13147 /* First make sure we didn't deduce anything that conflicts with
13148 explicitly specified args. */
13149 for (i = nargs; i--; )
13151 tree elt = TREE_VEC_ELT (tempargs, i);
13152 tree oldelt = TREE_VEC_ELT (orig_targs, i);
13156 else if (uses_template_parms (elt))
13157 /* Since we're unifying against ourselves, we will fill in
13158 template args used in the function parm list with our own
13159 template parms. Discard them. */
13160 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
13161 else if (oldelt && !template_args_equal (oldelt, elt))
13165 for (i = nargs; i--; )
13167 tree elt = TREE_VEC_ELT (tempargs, i);
13170 TREE_VEC_ELT (targs, i) = elt;
13176 /* PARM is a template class (perhaps with unbound template
13177 parameters). ARG is a fully instantiated type. If ARG can be
13178 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
13179 TARGS are as for unify. */
13182 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
13184 tree copy_of_targs;
13186 if (!CLASSTYPE_TEMPLATE_INFO (arg)
13187 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
13188 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
13191 /* We need to make a new template argument vector for the call to
13192 unify. If we used TARGS, we'd clutter it up with the result of
13193 the attempted unification, even if this class didn't work out.
13194 We also don't want to commit ourselves to all the unifications
13195 we've already done, since unification is supposed to be done on
13196 an argument-by-argument basis. In other words, consider the
13197 following pathological case:
13199 template <int I, int J, int K>
13202 template <int I, int J>
13203 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
13205 template <int I, int J, int K>
13206 void f(S<I, J, K>, S<I, I, I>);
13215 Now, by the time we consider the unification involving `s2', we
13216 already know that we must have `f<0, 0, 0>'. But, even though
13217 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
13218 because there are two ways to unify base classes of S<0, 1, 2>
13219 with S<I, I, I>. If we kept the already deduced knowledge, we
13220 would reject the possibility I=1. */
13221 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
13223 /* If unification failed, we're done. */
13224 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
13225 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
13231 /* Given a template type PARM and a class type ARG, find the unique
13232 base type in ARG that is an instance of PARM. We do not examine
13233 ARG itself; only its base-classes. If there is not exactly one
13234 appropriate base class, return NULL_TREE. PARM may be the type of
13235 a partial specialization, as well as a plain template type. Used
13239 get_template_base (tree tparms, tree targs, tree parm, tree arg)
13241 tree rval = NULL_TREE;
13244 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg)));
13246 binfo = TYPE_BINFO (complete_type (arg));
13248 /* The type could not be completed. */
13251 /* Walk in inheritance graph order. The search order is not
13252 important, and this avoids multiple walks of virtual bases. */
13253 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
13255 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
13259 /* If there is more than one satisfactory baseclass, then:
13263 If they yield more than one possible deduced A, the type
13267 if (rval && !same_type_p (r, rval))
13277 /* Returns the level of DECL, which declares a template parameter. */
13280 template_decl_level (tree decl)
13282 switch (TREE_CODE (decl))
13285 case TEMPLATE_DECL:
13286 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
13289 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
13292 gcc_unreachable ();
13297 /* Decide whether ARG can be unified with PARM, considering only the
13298 cv-qualifiers of each type, given STRICT as documented for unify.
13299 Returns nonzero iff the unification is OK on that basis. */
13302 check_cv_quals_for_unify (int strict, tree arg, tree parm)
13304 int arg_quals = cp_type_quals (arg);
13305 int parm_quals = cp_type_quals (parm);
13307 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13308 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
13310 /* Although a CVR qualifier is ignored when being applied to a
13311 substituted template parameter ([8.3.2]/1 for example), that
13312 does not apply during deduction [14.8.2.4]/1, (even though
13313 that is not explicitly mentioned, [14.8.2.4]/9 indicates
13314 this). Except when we're allowing additional CV qualifiers
13315 at the outer level [14.8.2.1]/3,1st bullet. */
13316 if ((TREE_CODE (arg) == REFERENCE_TYPE
13317 || TREE_CODE (arg) == FUNCTION_TYPE
13318 || TREE_CODE (arg) == METHOD_TYPE)
13319 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
13322 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
13323 && (parm_quals & TYPE_QUAL_RESTRICT))
13327 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
13328 && (arg_quals & parm_quals) != parm_quals)
13331 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
13332 && (parm_quals & arg_quals) != arg_quals)
13338 /* Determines the LEVEL and INDEX for the template parameter PARM. */
13340 template_parm_level_and_index (tree parm, int* level, int* index)
13342 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13343 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13344 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13346 *index = TEMPLATE_TYPE_IDX (parm);
13347 *level = TEMPLATE_TYPE_LEVEL (parm);
13351 *index = TEMPLATE_PARM_IDX (parm);
13352 *level = TEMPLATE_PARM_LEVEL (parm);
13356 /* Unifies the remaining arguments in PACKED_ARGS with the pack
13357 expansion at the end of PACKED_PARMS. Returns 0 if the type
13358 deduction succeeds, 1 otherwise. STRICT is the same as in
13359 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function
13360 call argument list. We'll need to adjust the arguments to make them
13361 types. SUBR tells us if this is from a recursive call to
13362 type_unification_real. */
13364 unify_pack_expansion (tree tparms, tree targs, tree packed_parms,
13365 tree packed_args, int strict, bool call_args_p,
13369 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1);
13370 tree pattern = PACK_EXPANSION_PATTERN (parm);
13371 tree pack, packs = NULL_TREE;
13372 int i, start = TREE_VEC_LENGTH (packed_parms) - 1;
13373 int len = TREE_VEC_LENGTH (packed_args);
13375 /* Determine the parameter packs we will be deducing from the
13376 pattern, and record their current deductions. */
13377 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm);
13378 pack; pack = TREE_CHAIN (pack))
13380 tree parm_pack = TREE_VALUE (pack);
13383 /* Determine the index and level of this parameter pack. */
13384 template_parm_level_and_index (parm_pack, &level, &idx);
13386 /* Keep track of the parameter packs and their corresponding
13388 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs);
13389 TREE_TYPE (packs) = make_tree_vec (len - start);
13392 /* Loop through all of the arguments that have not yet been
13393 unified and unify each with the pattern. */
13394 for (i = start; i < len; i++)
13396 tree parm = pattern;
13398 /* For each parameter pack, clear out the deduced value so that
13399 we can deduce it again. */
13400 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13403 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13405 TMPL_ARG (targs, level, idx) = NULL_TREE;
13408 /* Unify the pattern with the current argument. */
13410 tree arg = TREE_VEC_ELT (packed_args, i);
13411 tree arg_expr = NULL_TREE;
13412 int arg_strict = strict;
13413 bool skip_arg_p = false;
13419 /* This mirrors what we do in type_unification_real. */
13423 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL
13424 | UNIFY_ALLOW_MORE_CV_QUAL
13425 | UNIFY_ALLOW_DERIVED);
13429 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
13433 sub_strict = UNIFY_ALLOW_NONE;
13437 gcc_unreachable ();
13442 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
13443 if (type_unknown_p (arg))
13445 /* [temp.deduct.type] A template-argument can be
13446 deduced from a pointer to function or pointer
13447 to member function argument if the set of
13448 overloaded functions does not contain function
13449 templates and at most one of a set of
13450 overloaded functions provides a unique
13453 if (resolve_overloaded_unification
13454 (tparms, targs, parm, arg,
13455 (unification_kind_t) strict,
13465 arg = unlowered_expr_type (arg);
13466 if (arg == error_mark_node)
13471 arg_strict = sub_strict;
13475 maybe_adjust_types_for_deduction ((unification_kind_t) strict,
13476 &parm, &arg, arg_expr);
13481 if (unify (tparms, targs, parm, arg, arg_strict))
13486 /* For each parameter pack, collect the deduced value. */
13487 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13490 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13492 TREE_VEC_ELT (TREE_TYPE (pack), i - start) =
13493 TMPL_ARG (targs, level, idx);
13497 /* Verify that the results of unification with the parameter packs
13498 produce results consistent with what we've seen before, and make
13499 the deduced argument packs available. */
13500 for (pack = packs; pack; pack = TREE_CHAIN (pack))
13502 tree old_pack = TREE_VALUE (pack);
13503 tree new_args = TREE_TYPE (pack);
13504 int i, len = TREE_VEC_LENGTH (new_args);
13505 bool nondeduced_p = false;
13507 /* If NEW_ARGS contains any NULL_TREE entries, we didn't
13508 actually deduce anything. */
13509 for (i = 0; i < len && !nondeduced_p; ++i)
13510 if (TREE_VEC_ELT (new_args, i) == NULL_TREE)
13511 nondeduced_p = true;
13515 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack))
13517 /* Prepend the explicit arguments onto NEW_ARGS. */
13518 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack);
13519 tree old_args = new_args;
13520 int i, explicit_len = TREE_VEC_LENGTH (explicit_args);
13521 int len = explicit_len + TREE_VEC_LENGTH (old_args);
13523 /* Copy the explicit arguments. */
13524 new_args = make_tree_vec (len);
13525 for (i = 0; i < explicit_len; i++)
13526 TREE_VEC_ELT (new_args, i) = TREE_VEC_ELT (explicit_args, i);
13528 /* Copy the deduced arguments. */
13529 for (; i < len; i++)
13530 TREE_VEC_ELT (new_args, i) =
13531 TREE_VEC_ELT (old_args, i - explicit_len);
13539 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13541 /* Build the deduced *_ARGUMENT_PACK. */
13542 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX)
13544 result = make_node (NONTYPE_ARGUMENT_PACK);
13545 TREE_TYPE (result) =
13546 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack)));
13547 TREE_CONSTANT (result) = 1;
13550 result = make_node (TYPE_ARGUMENT_PACK);
13552 SET_ARGUMENT_PACK_ARGS (result, new_args);
13554 /* Note the deduced argument packs for this parameter
13556 TMPL_ARG (targs, level, idx) = result;
13558 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack)
13559 && (ARGUMENT_PACK_ARGS (old_pack)
13560 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack)))
13562 /* We only had the explicitly-provided arguments before, but
13563 now we have a complete set of arguments. */
13565 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_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;
13571 SET_ARGUMENT_PACK_ARGS (old_pack, new_args);
13572 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1;
13573 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args;
13575 else if (!comp_template_args (ARGUMENT_PACK_ARGS (old_pack),
13577 /* Inconsistent unification of this parameter pack. */
13583 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx);
13585 /* Keep the original deduced argument pack. */
13586 TMPL_ARG (targs, level, idx) = old_pack;
13593 /* Deduce the value of template parameters. TPARMS is the (innermost)
13594 set of template parameters to a template. TARGS is the bindings
13595 for those template parameters, as determined thus far; TARGS may
13596 include template arguments for outer levels of template parameters
13597 as well. PARM is a parameter to a template function, or a
13598 subcomponent of that parameter; ARG is the corresponding argument.
13599 This function attempts to match PARM with ARG in a manner
13600 consistent with the existing assignments in TARGS. If more values
13601 are deduced, then TARGS is updated.
13603 Returns 0 if the type deduction succeeds, 1 otherwise. The
13604 parameter STRICT is a bitwise or of the following flags:
13607 Require an exact match between PARM and ARG.
13608 UNIFY_ALLOW_MORE_CV_QUAL:
13609 Allow the deduced ARG to be more cv-qualified (by qualification
13610 conversion) than ARG.
13611 UNIFY_ALLOW_LESS_CV_QUAL:
13612 Allow the deduced ARG to be less cv-qualified than ARG.
13613 UNIFY_ALLOW_DERIVED:
13614 Allow the deduced ARG to be a template base class of ARG,
13615 or a pointer to a template base class of the type pointed to by
13617 UNIFY_ALLOW_INTEGER:
13618 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
13619 case for more information.
13620 UNIFY_ALLOW_OUTER_LEVEL:
13621 This is the outermost level of a deduction. Used to determine validity
13622 of qualification conversions. A valid qualification conversion must
13623 have const qualified pointers leading up to the inner type which
13624 requires additional CV quals, except at the outer level, where const
13625 is not required [conv.qual]. It would be normal to set this flag in
13626 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
13627 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
13628 This is the outermost level of a deduction, and PARM can be more CV
13629 qualified at this point.
13630 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
13631 This is the outermost level of a deduction, and PARM can be less CV
13632 qualified at this point. */
13635 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
13640 int strict_in = strict;
13642 /* I don't think this will do the right thing with respect to types.
13643 But the only case I've seen it in so far has been array bounds, where
13644 signedness is the only information lost, and I think that will be
13646 while (TREE_CODE (parm) == NOP_EXPR)
13647 parm = TREE_OPERAND (parm, 0);
13649 if (arg == error_mark_node)
13651 if (arg == unknown_type_node
13652 || arg == init_list_type_node)
13653 /* We can't deduce anything from this, but we might get all the
13654 template args from other function args. */
13657 /* If PARM uses template parameters, then we can't bail out here,
13658 even if ARG == PARM, since we won't record unifications for the
13659 template parameters. We might need them if we're trying to
13660 figure out which of two things is more specialized. */
13661 if (arg == parm && !uses_template_parms (parm))
13664 /* Handle init lists early, so the rest of the function can assume
13665 we're dealing with a type. */
13666 if (BRACE_ENCLOSED_INITIALIZER_P (arg))
13671 if (!is_std_init_list (parm))
13672 /* We can only deduce from an initializer list argument if the
13673 parameter is std::initializer_list; otherwise this is a
13674 non-deduced context. */
13677 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0);
13679 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt)
13681 int elt_strict = strict;
13682 if (!BRACE_ENCLOSED_INITIALIZER_P (elt))
13684 tree type = TREE_TYPE (elt);
13685 /* It should only be possible to get here for a call. */
13686 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL);
13687 elt_strict |= maybe_adjust_types_for_deduction
13688 (DEDUCE_CALL, &elttype, &type, elt);
13692 if (unify (tparms, targs, elttype, elt, elt_strict))
13698 /* Immediately reject some pairs that won't unify because of
13699 cv-qualification mismatches. */
13700 if (TREE_CODE (arg) == TREE_CODE (parm)
13702 /* It is the elements of the array which hold the cv quals of an array
13703 type, and the elements might be template type parms. We'll check
13704 when we recurse. */
13705 && TREE_CODE (arg) != ARRAY_TYPE
13706 /* We check the cv-qualifiers when unifying with template type
13707 parameters below. We want to allow ARG `const T' to unify with
13708 PARM `T' for example, when computing which of two templates
13709 is more specialized, for example. */
13710 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
13711 && !check_cv_quals_for_unify (strict_in, arg, parm))
13714 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
13715 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
13716 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
13717 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
13718 strict &= ~UNIFY_ALLOW_DERIVED;
13719 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
13720 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
13722 switch (TREE_CODE (parm))
13724 case TYPENAME_TYPE:
13726 case UNBOUND_CLASS_TEMPLATE:
13727 /* In a type which contains a nested-name-specifier, template
13728 argument values cannot be deduced for template parameters used
13729 within the nested-name-specifier. */
13732 case TEMPLATE_TYPE_PARM:
13733 case TEMPLATE_TEMPLATE_PARM:
13734 case BOUND_TEMPLATE_TEMPLATE_PARM:
13735 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
13736 if (tparm == error_mark_node)
13739 if (TEMPLATE_TYPE_LEVEL (parm)
13740 != template_decl_level (tparm))
13741 /* The PARM is not one we're trying to unify. Just check
13742 to see if it matches ARG. */
13743 return (TREE_CODE (arg) == TREE_CODE (parm)
13744 && same_type_p (parm, arg)) ? 0 : 1;
13745 idx = TEMPLATE_TYPE_IDX (parm);
13746 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
13747 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
13749 /* Check for mixed types and values. */
13750 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
13751 && TREE_CODE (tparm) != TYPE_DECL)
13752 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13753 && TREE_CODE (tparm) != TEMPLATE_DECL))
13756 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13758 /* ARG must be constructed from a template class or a template
13759 template parameter. */
13760 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
13761 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg))
13765 tree parmvec = TYPE_TI_ARGS (parm);
13766 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
13768 = DECL_INNERMOST_TEMPLATE_PARMS
13769 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm));
13771 int parm_variadic_p = 0;
13773 /* The resolution to DR150 makes clear that default
13774 arguments for an N-argument may not be used to bind T
13775 to a template template parameter with fewer than N
13776 parameters. It is not safe to permit the binding of
13777 default arguments as an extension, as that may change
13778 the meaning of a conforming program. Consider:
13780 struct Dense { static const unsigned int dim = 1; };
13782 template <template <typename> class View,
13784 void operator+(float, View<Block> const&);
13786 template <typename Block,
13787 unsigned int Dim = Block::dim>
13788 struct Lvalue_proxy { operator float() const; };
13792 Lvalue_proxy<Dense> p;
13797 Here, if Lvalue_proxy is permitted to bind to View, then
13798 the global operator+ will be used; if they are not, the
13799 Lvalue_proxy will be converted to float. */
13800 if (coerce_template_parms (parm_parms,
13802 TYPE_TI_TEMPLATE (parm),
13804 /*require_all_args=*/true,
13805 /*use_default_args=*/false)
13806 == error_mark_node)
13809 /* Deduce arguments T, i from TT<T> or TT<i>.
13810 We check each element of PARMVEC and ARGVEC individually
13811 rather than the whole TREE_VEC since they can have
13812 different number of elements. */
13814 parmvec = expand_template_argument_pack (parmvec);
13815 argvec = expand_template_argument_pack (argvec);
13817 len = TREE_VEC_LENGTH (parmvec);
13819 /* Check if the parameters end in a pack, making them
13822 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1)))
13823 parm_variadic_p = 1;
13825 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p)
13828 for (i = 0; i < len - parm_variadic_p; ++i)
13830 if (unify (tparms, targs,
13831 TREE_VEC_ELT (parmvec, i),
13832 TREE_VEC_ELT (argvec, i),
13837 if (parm_variadic_p
13838 && unify_pack_expansion (tparms, targs,
13841 /*call_args_p=*/false,
13845 arg = TYPE_TI_TEMPLATE (arg);
13847 /* Fall through to deduce template name. */
13850 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
13851 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
13853 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
13855 /* Simple cases: Value already set, does match or doesn't. */
13856 if (targ != NULL_TREE && template_args_equal (targ, arg))
13863 /* If PARM is `const T' and ARG is only `int', we don't have
13864 a match unless we are allowing additional qualification.
13865 If ARG is `const int' and PARM is just `T' that's OK;
13866 that binds `const int' to `T'. */
13867 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
13871 /* Consider the case where ARG is `const volatile int' and
13872 PARM is `const T'. Then, T should be `volatile int'. */
13873 arg = cp_build_qualified_type_real
13874 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
13875 if (arg == error_mark_node)
13878 /* Simple cases: Value already set, does match or doesn't. */
13879 if (targ != NULL_TREE && same_type_p (targ, arg))
13884 /* Make sure that ARG is not a variable-sized array. (Note
13885 that were talking about variable-sized arrays (like
13886 `int[n]'), rather than arrays of unknown size (like
13887 `int[]').) We'll get very confused by such a type since
13888 the bound of the array will not be computable in an
13889 instantiation. Besides, such types are not allowed in
13890 ISO C++, so we can do as we please here. */
13891 if (variably_modified_type_p (arg, NULL_TREE))
13894 /* Strip typedefs as in convert_template_argument. */
13895 arg = strip_typedefs (arg);
13898 /* If ARG is a parameter pack or an expansion, we cannot unify
13899 against it unless PARM is also a parameter pack. */
13900 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
13901 && !template_parameter_pack_p (parm))
13904 /* If the argument deduction results is a METHOD_TYPE,
13905 then there is a problem.
13906 METHOD_TYPE doesn't map to any real C++ type the result of
13907 the deduction can not be of that type. */
13908 if (TREE_CODE (arg) == METHOD_TYPE)
13911 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
13914 case TEMPLATE_PARM_INDEX:
13915 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
13916 if (tparm == error_mark_node)
13919 if (TEMPLATE_PARM_LEVEL (parm)
13920 != template_decl_level (tparm))
13921 /* The PARM is not one we're trying to unify. Just check
13922 to see if it matches ARG. */
13923 return !(TREE_CODE (arg) == TREE_CODE (parm)
13924 && cp_tree_equal (parm, arg));
13926 idx = TEMPLATE_PARM_IDX (parm);
13927 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx);
13930 return !cp_tree_equal (targ, arg);
13932 /* [temp.deduct.type] If, in the declaration of a function template
13933 with a non-type template-parameter, the non-type
13934 template-parameter is used in an expression in the function
13935 parameter-list and, if the corresponding template-argument is
13936 deduced, the template-argument type shall match the type of the
13937 template-parameter exactly, except that a template-argument
13938 deduced from an array bound may be of any integral type.
13939 The non-type parameter might use already deduced type parameters. */
13940 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
13941 if (!TREE_TYPE (arg))
13942 /* Template-parameter dependent expression. Just accept it for now.
13943 It will later be processed in convert_template_argument. */
13945 else if (same_type_p (TREE_TYPE (arg), tparm))
13947 else if ((strict & UNIFY_ALLOW_INTEGER)
13948 && (TREE_CODE (tparm) == INTEGER_TYPE
13949 || TREE_CODE (tparm) == BOOLEAN_TYPE))
13950 /* Convert the ARG to the type of PARM; the deduced non-type
13951 template argument must exactly match the types of the
13952 corresponding parameter. */
13953 arg = fold (build_nop (tparm, arg));
13954 else if (uses_template_parms (tparm))
13955 /* We haven't deduced the type of this parameter yet. Try again
13961 /* If ARG is a parameter pack or an expansion, we cannot unify
13962 against it unless PARM is also a parameter pack. */
13963 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg))
13964 && !TEMPLATE_PARM_PARAMETER_PACK (parm))
13967 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg;
13972 /* A pointer-to-member constant can be unified only with
13973 another constant. */
13974 if (TREE_CODE (arg) != PTRMEM_CST)
13977 /* Just unify the class member. It would be useless (and possibly
13978 wrong, depending on the strict flags) to unify also
13979 PTRMEM_CST_CLASS, because we want to be sure that both parm and
13980 arg refer to the same variable, even if through different
13981 classes. For instance:
13983 struct A { int x; };
13986 Unification of &A::x and &B::x must succeed. */
13987 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
13988 PTRMEM_CST_MEMBER (arg), strict);
13993 if (TREE_CODE (arg) != POINTER_TYPE)
13996 /* [temp.deduct.call]
13998 A can be another pointer or pointer to member type that can
13999 be converted to the deduced A via a qualification
14000 conversion (_conv.qual_).
14002 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
14003 This will allow for additional cv-qualification of the
14004 pointed-to types if appropriate. */
14006 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
14007 /* The derived-to-base conversion only persists through one
14008 level of pointers. */
14009 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
14011 return unify (tparms, targs, TREE_TYPE (parm),
14012 TREE_TYPE (arg), strict);
14015 case REFERENCE_TYPE:
14016 if (TREE_CODE (arg) != REFERENCE_TYPE)
14018 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14019 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14022 if (TREE_CODE (arg) != ARRAY_TYPE)
14024 if ((TYPE_DOMAIN (parm) == NULL_TREE)
14025 != (TYPE_DOMAIN (arg) == NULL_TREE))
14027 if (TYPE_DOMAIN (parm) != NULL_TREE)
14034 /* Our representation of array types uses "N - 1" as the
14035 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
14036 not an integer constant. We cannot unify arbitrarily
14037 complex expressions, so we eliminate the MINUS_EXPRs
14039 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
14040 parm_cst = TREE_CODE (parm_max) == INTEGER_CST;
14043 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR);
14044 parm_max = TREE_OPERAND (parm_max, 0);
14046 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
14047 arg_cst = TREE_CODE (arg_max) == INTEGER_CST;
14050 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are
14051 trying to unify the type of a variable with the type
14052 of a template parameter. For example:
14054 template <unsigned int N>
14055 void f (char (&) [N]);
14062 Here, the type of the ARG will be "int [g(i)]", and
14063 may be a SAVE_EXPR, etc. */
14064 if (TREE_CODE (arg_max) != MINUS_EXPR)
14066 arg_max = TREE_OPERAND (arg_max, 0);
14069 /* If only one of the bounds used a MINUS_EXPR, compensate
14070 by adding one to the other bound. */
14071 if (parm_cst && !arg_cst)
14072 parm_max = fold_build2 (PLUS_EXPR,
14076 else if (arg_cst && !parm_cst)
14077 arg_max = fold_build2 (PLUS_EXPR,
14082 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
14085 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14086 strict & UNIFY_ALLOW_MORE_CV_QUAL);
14093 case ENUMERAL_TYPE:
14095 if (TREE_CODE (arg) != TREE_CODE (parm))
14098 /* We have already checked cv-qualification at the top of the
14100 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
14103 /* As far as unification is concerned, this wins. Later checks
14104 will invalidate it if necessary. */
14107 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
14108 /* Type INTEGER_CST can come from ordinary constant template args. */
14110 while (TREE_CODE (arg) == NOP_EXPR)
14111 arg = TREE_OPERAND (arg, 0);
14113 if (TREE_CODE (arg) != INTEGER_CST)
14115 return !tree_int_cst_equal (parm, arg);
14120 if (TREE_CODE (arg) != TREE_VEC)
14122 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
14124 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
14125 if (unify (tparms, targs,
14126 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
14134 if (TREE_CODE (arg) != TREE_CODE (parm))
14137 if (TYPE_PTRMEMFUNC_P (parm))
14139 if (!TYPE_PTRMEMFUNC_P (arg))
14142 return unify (tparms, targs,
14143 TYPE_PTRMEMFUNC_FN_TYPE (parm),
14144 TYPE_PTRMEMFUNC_FN_TYPE (arg),
14148 if (CLASSTYPE_TEMPLATE_INFO (parm))
14150 tree t = NULL_TREE;
14152 if (strict_in & UNIFY_ALLOW_DERIVED)
14154 /* First, we try to unify the PARM and ARG directly. */
14155 t = try_class_unification (tparms, targs,
14160 /* Fallback to the special case allowed in
14161 [temp.deduct.call]:
14163 If P is a class, and P has the form
14164 template-id, then A can be a derived class of
14165 the deduced A. Likewise, if P is a pointer to
14166 a class of the form template-id, A can be a
14167 pointer to a derived class pointed to by the
14169 t = get_template_base (tparms, targs, parm, arg);
14175 else if (CLASSTYPE_TEMPLATE_INFO (arg)
14176 && (CLASSTYPE_TI_TEMPLATE (parm)
14177 == CLASSTYPE_TI_TEMPLATE (arg)))
14178 /* Perhaps PARM is something like S<U> and ARG is S<int>.
14179 Then, we should unify `int' and `U'. */
14182 /* There's no chance of unification succeeding. */
14185 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
14186 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
14188 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
14193 case FUNCTION_TYPE:
14195 unsigned int nargs;
14200 if (TREE_CODE (arg) != TREE_CODE (parm))
14203 /* CV qualifications for methods can never be deduced, they must
14204 match exactly. We need to check them explicitly here,
14205 because type_unification_real treats them as any other
14206 cv-qualified parameter. */
14207 if (TREE_CODE (parm) == METHOD_TYPE
14208 && (!check_cv_quals_for_unify
14210 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
14211 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
14214 if (unify (tparms, targs, TREE_TYPE (parm),
14215 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
14218 nargs = list_length (TYPE_ARG_TYPES (arg));
14219 args = XALLOCAVEC (tree, nargs);
14220 for (a = TYPE_ARG_TYPES (arg), i = 0;
14221 a != NULL_TREE && a != void_list_node;
14222 a = TREE_CHAIN (a), ++i)
14223 args[i] = TREE_VALUE (a);
14226 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
14227 args, nargs, 1, DEDUCE_EXACT,
14232 /* Unify a pointer to member with a pointer to member function, which
14233 deduces the type of the member as a function type. */
14234 if (TYPE_PTRMEMFUNC_P (arg))
14238 cp_cv_quals cv_quals;
14240 /* Check top-level cv qualifiers */
14241 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
14244 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14245 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
14248 /* Determine the type of the function we are unifying against. */
14249 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
14251 build_function_type (TREE_TYPE (method_type),
14252 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
14254 /* Extract the cv-qualifiers of the member function from the
14255 implicit object parameter and place them on the function
14256 type to be restored later. */
14258 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
14259 fntype = build_qualified_type (fntype, cv_quals);
14260 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
14263 if (TREE_CODE (arg) != OFFSET_TYPE)
14265 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
14266 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
14268 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
14272 if (DECL_TEMPLATE_PARM_P (parm))
14273 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
14274 if (arg != integral_constant_value (parm))
14279 case TEMPLATE_DECL:
14280 /* Matched cases are handled by the ARG == PARM test above. */
14283 case TYPE_ARGUMENT_PACK:
14284 case NONTYPE_ARGUMENT_PACK:
14286 tree packed_parms = ARGUMENT_PACK_ARGS (parm);
14287 tree packed_args = ARGUMENT_PACK_ARGS (arg);
14288 int i, len = TREE_VEC_LENGTH (packed_parms);
14289 int argslen = TREE_VEC_LENGTH (packed_args);
14290 int parm_variadic_p = 0;
14292 for (i = 0; i < len; ++i)
14294 if (PACK_EXPANSION_P (TREE_VEC_ELT (packed_parms, i)))
14297 /* We can unify against something with a trailing
14299 parm_variadic_p = 1;
14301 /* Since there is something following the pack
14302 expansion, we cannot unify this template argument
14309 /* If we don't have enough arguments to satisfy the parameters
14310 (not counting the pack expression at the end), or we have
14311 too many arguments for a parameter list that doesn't end in
14312 a pack expression, we can't unify. */
14313 if (argslen < (len - parm_variadic_p)
14314 || (argslen > len && !parm_variadic_p))
14317 /* Unify all of the parameters that precede the (optional)
14318 pack expression. */
14319 for (i = 0; i < len - parm_variadic_p; ++i)
14321 if (unify (tparms, targs, TREE_VEC_ELT (packed_parms, i),
14322 TREE_VEC_ELT (packed_args, i), strict))
14326 if (parm_variadic_p)
14327 return unify_pack_expansion (tparms, targs,
14328 packed_parms, packed_args,
14329 strict, /*call_args_p=*/false,
14337 case DECLTYPE_TYPE:
14338 /* Cannot deduce anything from TYPEOF_TYPE or DECLTYPE_TYPE
14343 /* Unification fails if we hit an error node. */
14347 gcc_assert (EXPR_P (parm));
14349 /* We must be looking at an expression. This can happen with
14353 void foo(S<I>, S<I + 2>);
14355 This is a "nondeduced context":
14359 The nondeduced contexts are:
14361 --A type that is a template-id in which one or more of
14362 the template-arguments is an expression that references
14363 a template-parameter.
14365 In these cases, we assume deduction succeeded, but don't
14366 actually infer any unifications. */
14368 if (!uses_template_parms (parm)
14369 && !template_args_equal (parm, arg))
14376 /* Note that DECL can be defined in this translation unit, if
14380 mark_definable (tree decl)
14383 DECL_NOT_REALLY_EXTERN (decl) = 1;
14384 FOR_EACH_CLONE (clone, decl)
14385 DECL_NOT_REALLY_EXTERN (clone) = 1;
14388 /* Called if RESULT is explicitly instantiated, or is a member of an
14389 explicitly instantiated class. */
14392 mark_decl_instantiated (tree result, int extern_p)
14394 SET_DECL_EXPLICIT_INSTANTIATION (result);
14396 /* If this entity has already been written out, it's too late to
14397 make any modifications. */
14398 if (TREE_ASM_WRITTEN (result))
14401 if (TREE_CODE (result) != FUNCTION_DECL)
14402 /* The TREE_PUBLIC flag for function declarations will have been
14403 set correctly by tsubst. */
14404 TREE_PUBLIC (result) = 1;
14406 /* This might have been set by an earlier implicit instantiation. */
14407 DECL_COMDAT (result) = 0;
14410 DECL_NOT_REALLY_EXTERN (result) = 0;
14413 mark_definable (result);
14414 /* Always make artificials weak. */
14415 if (DECL_ARTIFICIAL (result) && flag_weak)
14416 comdat_linkage (result);
14417 /* For WIN32 we also want to put explicit instantiations in
14418 linkonce sections. */
14419 else if (TREE_PUBLIC (result))
14420 maybe_make_one_only (result);
14423 /* If EXTERN_P, then this function will not be emitted -- unless
14424 followed by an explicit instantiation, at which point its linkage
14425 will be adjusted. If !EXTERN_P, then this function will be
14426 emitted here. In neither circumstance do we want
14427 import_export_decl to adjust the linkage. */
14428 DECL_INTERFACE_KNOWN (result) = 1;
14431 /* Given two function templates PAT1 and PAT2, return:
14433 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
14434 -1 if PAT2 is more specialized than PAT1.
14435 0 if neither is more specialized.
14437 LEN indicates the number of parameters we should consider
14438 (defaulted parameters should not be considered).
14440 The 1998 std underspecified function template partial ordering, and
14441 DR214 addresses the issue. We take pairs of arguments, one from
14442 each of the templates, and deduce them against each other. One of
14443 the templates will be more specialized if all the *other*
14444 template's arguments deduce against its arguments and at least one
14445 of its arguments *does* *not* deduce against the other template's
14446 corresponding argument. Deduction is done as for class templates.
14447 The arguments used in deduction have reference and top level cv
14448 qualifiers removed. Iff both arguments were originally reference
14449 types *and* deduction succeeds in both directions, the template
14450 with the more cv-qualified argument wins for that pairing (if
14451 neither is more cv-qualified, they both are equal). Unlike regular
14452 deduction, after all the arguments have been deduced in this way,
14453 we do *not* verify the deduced template argument values can be
14454 substituted into non-deduced contexts, nor do we have to verify
14455 that all template arguments have been deduced. */
14458 more_specialized_fn (tree pat1, tree pat2, int len)
14460 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
14461 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
14462 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
14463 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
14464 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
14465 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
14466 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
14467 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
14471 /* Remove the this parameter from non-static member functions. If
14472 one is a non-static member function and the other is not a static
14473 member function, remove the first parameter from that function
14474 also. This situation occurs for operator functions where we
14475 locate both a member function (with this pointer) and non-member
14476 operator (with explicit first operand). */
14477 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
14479 len--; /* LEN is the number of significant arguments for DECL1 */
14480 args1 = TREE_CHAIN (args1);
14481 if (!DECL_STATIC_FUNCTION_P (decl2))
14482 args2 = TREE_CHAIN (args2);
14484 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
14486 args2 = TREE_CHAIN (args2);
14487 if (!DECL_STATIC_FUNCTION_P (decl1))
14490 args1 = TREE_CHAIN (args1);
14494 /* If only one is a conversion operator, they are unordered. */
14495 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
14498 /* Consider the return type for a conversion function */
14499 if (DECL_CONV_FN_P (decl1))
14501 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
14502 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
14506 processing_template_decl++;
14509 /* Stop when an ellipsis is seen. */
14510 && args1 != NULL_TREE && args2 != NULL_TREE)
14512 tree arg1 = TREE_VALUE (args1);
14513 tree arg2 = TREE_VALUE (args2);
14514 int deduce1, deduce2;
14518 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
14519 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
14521 /* When both arguments are pack expansions, we need only
14522 unify the patterns themselves. */
14523 arg1 = PACK_EXPANSION_PATTERN (arg1);
14524 arg2 = PACK_EXPANSION_PATTERN (arg2);
14526 /* This is the last comparison we need to do. */
14530 if (TREE_CODE (arg1) == REFERENCE_TYPE)
14532 arg1 = TREE_TYPE (arg1);
14533 quals1 = cp_type_quals (arg1);
14536 if (TREE_CODE (arg2) == REFERENCE_TYPE)
14538 arg2 = TREE_TYPE (arg2);
14539 quals2 = cp_type_quals (arg2);
14542 if ((quals1 < 0) != (quals2 < 0))
14544 /* Only of the args is a reference, see if we should apply
14545 array/function pointer decay to it. This is not part of
14546 DR214, but is, IMHO, consistent with the deduction rules
14547 for the function call itself, and with our earlier
14548 implementation of the underspecified partial ordering
14549 rules. (nathan). */
14552 switch (TREE_CODE (arg1))
14555 arg1 = TREE_TYPE (arg1);
14557 case FUNCTION_TYPE:
14558 arg1 = build_pointer_type (arg1);
14567 switch (TREE_CODE (arg2))
14570 arg2 = TREE_TYPE (arg2);
14572 case FUNCTION_TYPE:
14573 arg2 = build_pointer_type (arg2);
14582 arg1 = TYPE_MAIN_VARIANT (arg1);
14583 arg2 = TYPE_MAIN_VARIANT (arg2);
14585 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION)
14587 int i, len2 = list_length (args2);
14588 tree parmvec = make_tree_vec (1);
14589 tree argvec = make_tree_vec (len2);
14592 /* Setup the parameter vector, which contains only ARG1. */
14593 TREE_VEC_ELT (parmvec, 0) = arg1;
14595 /* Setup the argument vector, which contains the remaining
14597 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta))
14598 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
14600 deduce1 = !unify_pack_expansion (tparms1, targs1, parmvec,
14601 argvec, UNIFY_ALLOW_NONE,
14602 /*call_args_p=*/false,
14605 /* We cannot deduce in the other direction, because ARG1 is
14606 a pack expansion but ARG2 is not. */
14609 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
14611 int i, len1 = list_length (args1);
14612 tree parmvec = make_tree_vec (1);
14613 tree argvec = make_tree_vec (len1);
14616 /* Setup the parameter vector, which contains only ARG1. */
14617 TREE_VEC_ELT (parmvec, 0) = arg2;
14619 /* Setup the argument vector, which contains the remaining
14621 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta))
14622 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta);
14624 deduce2 = !unify_pack_expansion (tparms2, targs2, parmvec,
14625 argvec, UNIFY_ALLOW_NONE,
14626 /*call_args_p=*/false,
14629 /* We cannot deduce in the other direction, because ARG2 is
14630 a pack expansion but ARG1 is not.*/
14636 /* The normal case, where neither argument is a pack
14638 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
14639 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
14646 if (better1 < 0 && better2 < 0)
14647 /* We've failed to deduce something in either direction.
14648 These must be unordered. */
14651 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
14653 /* Deduces in both directions, see if quals can
14654 disambiguate. Pretend the worse one failed to deduce. */
14655 if ((quals1 & quals2) == quals2)
14657 if ((quals1 & quals2) == quals1)
14660 if (deduce1 && !deduce2 && !better2)
14662 if (deduce2 && !deduce1 && !better1)
14665 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION
14666 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION)
14667 /* We have already processed all of the arguments in our
14668 handing of the pack expansion type. */
14671 args1 = TREE_CHAIN (args1);
14672 args2 = TREE_CHAIN (args2);
14675 processing_template_decl--;
14677 /* All things being equal, if the next argument is a pack expansion
14678 for one function but not for the other, prefer the
14679 non-variadic function. */
14680 if ((better1 > 0) - (better2 > 0) == 0
14681 && args1 && TREE_VALUE (args1)
14682 && args2 && TREE_VALUE (args2))
14684 if (TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION)
14685 return TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION ? 0 : -1;
14686 else if (TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION)
14690 return (better1 > 0) - (better2 > 0);
14693 /* Determine which of two partial specializations is more specialized.
14695 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding
14696 to the first partial specialization. The TREE_VALUE is the
14697 innermost set of template parameters for the partial
14698 specialization. PAT2 is similar, but for the second template.
14700 Return 1 if the first partial specialization is more specialized;
14701 -1 if the second is more specialized; 0 if neither is more
14704 See [temp.class.order] for information about determining which of
14705 two templates is more specialized. */
14708 more_specialized_class (tree pat1, tree pat2)
14713 bool any_deductions = false;
14715 tmpl1 = TREE_TYPE (pat1);
14716 tmpl2 = TREE_TYPE (pat2);
14718 /* Just like what happens for functions, if we are ordering between
14719 different class template specializations, we may encounter dependent
14720 types in the arguments, and we need our dependency check functions
14721 to behave correctly. */
14722 ++processing_template_decl;
14723 targs = get_class_bindings (TREE_VALUE (pat1),
14724 CLASSTYPE_TI_ARGS (tmpl1),
14725 CLASSTYPE_TI_ARGS (tmpl2));
14729 any_deductions = true;
14732 targs = get_class_bindings (TREE_VALUE (pat2),
14733 CLASSTYPE_TI_ARGS (tmpl2),
14734 CLASSTYPE_TI_ARGS (tmpl1));
14738 any_deductions = true;
14740 --processing_template_decl;
14742 /* In the case of a tie where at least one of the class templates
14743 has a parameter pack at the end, the template with the most
14744 non-packed parameters wins. */
14747 && (template_args_variadic_p (TREE_PURPOSE (pat1))
14748 || template_args_variadic_p (TREE_PURPOSE (pat2))))
14750 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1));
14751 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2));
14752 int len1 = TREE_VEC_LENGTH (args1);
14753 int len2 = TREE_VEC_LENGTH (args2);
14755 /* We don't count the pack expansion at the end. */
14756 if (template_args_variadic_p (TREE_PURPOSE (pat1)))
14758 if (template_args_variadic_p (TREE_PURPOSE (pat2)))
14763 else if (len1 < len2)
14770 /* Return the template arguments that will produce the function signature
14771 DECL from the function template FN, with the explicit template
14772 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
14773 also match. Return NULL_TREE if no satisfactory arguments could be
14777 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
14779 int ntparms = DECL_NTPARMS (fn);
14780 tree targs = make_tree_vec (ntparms);
14782 tree decl_arg_types;
14784 unsigned int nargs, ix;
14787 /* Substitute the explicit template arguments into the type of DECL.
14788 The call to fn_type_unification will handle substitution into the
14790 decl_type = TREE_TYPE (decl);
14791 if (explicit_args && uses_template_parms (decl_type))
14794 tree converted_args;
14796 if (DECL_TEMPLATE_INFO (decl))
14797 tmpl = DECL_TI_TEMPLATE (decl);
14799 /* We can get here for some invalid specializations. */
14803 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
14804 explicit_args, NULL_TREE,
14806 /*require_all_args=*/false,
14807 /*use_default_args=*/false);
14808 if (converted_args == error_mark_node)
14811 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
14812 if (decl_type == error_mark_node)
14816 /* Never do unification on the 'this' parameter. */
14817 decl_arg_types = skip_artificial_parms_for (decl,
14818 TYPE_ARG_TYPES (decl_type));
14820 nargs = list_length (decl_arg_types);
14821 args = XALLOCAVEC (tree, nargs);
14822 for (arg = decl_arg_types, ix = 0;
14823 arg != NULL_TREE && arg != void_list_node;
14824 arg = TREE_CHAIN (arg), ++ix)
14825 args[ix] = TREE_VALUE (arg);
14827 if (fn_type_unification (fn, explicit_args, targs,
14829 (check_rettype || DECL_CONV_FN_P (fn)
14830 ? TREE_TYPE (decl_type) : NULL_TREE),
14831 DEDUCE_EXACT, LOOKUP_NORMAL))
14837 /* Return the innermost template arguments that, when applied to a
14838 template specialization whose innermost template parameters are
14839 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the
14842 For example, suppose we have:
14844 template <class T, class U> struct S {};
14845 template <class T> struct S<T*, int> {};
14847 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
14848 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*,
14849 int}. The resulting vector will be {double}, indicating that `T'
14850 is bound to `double'. */
14853 get_class_bindings (tree tparms, tree spec_args, tree args)
14855 int i, ntparms = TREE_VEC_LENGTH (tparms);
14857 tree innermost_deduced_args;
14859 innermost_deduced_args = make_tree_vec (ntparms);
14860 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
14862 deduced_args = copy_node (args);
14863 SET_TMPL_ARGS_LEVEL (deduced_args,
14864 TMPL_ARGS_DEPTH (deduced_args),
14865 innermost_deduced_args);
14868 deduced_args = innermost_deduced_args;
14870 if (unify (tparms, deduced_args,
14871 INNERMOST_TEMPLATE_ARGS (spec_args),
14872 INNERMOST_TEMPLATE_ARGS (args),
14876 for (i = 0; i < ntparms; ++i)
14877 if (! TREE_VEC_ELT (innermost_deduced_args, i))
14880 /* Verify that nondeduced template arguments agree with the type
14881 obtained from argument deduction.
14885 struct A { typedef int X; };
14886 template <class T, class U> struct C {};
14887 template <class T> struct C<T, typename T::X> {};
14889 Then with the instantiation `C<A, int>', we can deduce that
14890 `T' is `A' but unify () does not check whether `typename T::X'
14892 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE);
14893 if (spec_args == error_mark_node
14894 /* We only need to check the innermost arguments; the other
14895 arguments will always agree. */
14896 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args),
14897 INNERMOST_TEMPLATE_ARGS (args)))
14900 /* Now that we have bindings for all of the template arguments,
14901 ensure that the arguments deduced for the template template
14902 parameters have compatible template parameter lists. See the use
14903 of template_template_parm_bindings_ok_p in fn_type_unification
14904 for more information. */
14905 if (!template_template_parm_bindings_ok_p (tparms, deduced_args))
14908 return deduced_args;
14911 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL.
14912 Return the TREE_LIST node with the most specialized template, if
14913 any. If there is no most specialized template, the error_mark_node
14916 Note that this function does not look at, or modify, the
14917 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node
14918 returned is one of the elements of INSTANTIATIONS, callers may
14919 store information in the TREE_PURPOSE or TREE_TYPE of the nodes,
14920 and retrieve it from the value returned. */
14923 most_specialized_instantiation (tree templates)
14927 ++processing_template_decl;
14930 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn))
14934 if (get_bindings (TREE_VALUE (champ),
14935 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
14936 NULL_TREE, /*check_ret=*/false))
14939 if (get_bindings (TREE_VALUE (fn),
14940 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
14941 NULL_TREE, /*check_ret=*/false))
14948 /* Equally specialized, move to next function. If there
14949 is no next function, nothing's most specialized. */
14950 fn = TREE_CHAIN (fn);
14958 /* Now verify that champ is better than everything earlier in the
14959 instantiation list. */
14960 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn))
14961 if (get_bindings (TREE_VALUE (champ),
14962 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
14963 NULL_TREE, /*check_ret=*/false)
14964 || !get_bindings (TREE_VALUE (fn),
14965 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
14966 NULL_TREE, /*check_ret=*/false))
14972 processing_template_decl--;
14975 return error_mark_node;
14980 /* If DECL is a specialization of some template, return the most
14981 general such template. Otherwise, returns NULL_TREE.
14983 For example, given:
14985 template <class T> struct S { template <class U> void f(U); };
14987 if TMPL is `template <class U> void S<int>::f(U)' this will return
14988 the full template. This function will not trace past partial
14989 specializations, however. For example, given in addition:
14991 template <class T> struct S<T*> { template <class U> void f(U); };
14993 if TMPL is `template <class U> void S<int*>::f(U)' this will return
14994 `template <class T> template <class U> S<T*>::f(U)'. */
14997 most_general_template (tree decl)
14999 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
15000 an immediate specialization. */
15001 if (TREE_CODE (decl) == FUNCTION_DECL)
15003 if (DECL_TEMPLATE_INFO (decl)) {
15004 decl = DECL_TI_TEMPLATE (decl);
15006 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
15007 template friend. */
15008 if (TREE_CODE (decl) != TEMPLATE_DECL)
15014 /* Look for more and more general templates. */
15015 while (DECL_TEMPLATE_INFO (decl))
15017 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
15018 (See cp-tree.h for details.) */
15019 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
15022 if (CLASS_TYPE_P (TREE_TYPE (decl))
15023 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
15026 /* Stop if we run into an explicitly specialized class template. */
15027 if (!DECL_NAMESPACE_SCOPE_P (decl)
15028 && DECL_CONTEXT (decl)
15029 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
15032 decl = DECL_TI_TEMPLATE (decl);
15038 /* Return the most specialized of the class template partial
15039 specializations of TMPL which can produce TYPE, a specialization of
15040 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is
15041 a _TYPE node corresponding to the partial specialization, while the
15042 TREE_PURPOSE is the set of template arguments that must be
15043 substituted into the TREE_TYPE in order to generate TYPE.
15045 If the choice of partial specialization is ambiguous, a diagnostic
15046 is issued, and the error_mark_node is returned. If there are no
15047 partial specializations of TMPL matching TYPE, then NULL_TREE is
15051 most_specialized_class (tree type, tree tmpl)
15053 tree list = NULL_TREE;
15059 tree outer_args = NULL_TREE;
15061 tmpl = most_general_template (tmpl);
15062 args = CLASSTYPE_TI_ARGS (type);
15064 /* For determining which partial specialization to use, only the
15065 innermost args are interesting. */
15066 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
15068 outer_args = strip_innermost_template_args (args, 1);
15069 args = INNERMOST_TEMPLATE_ARGS (args);
15072 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
15074 tree partial_spec_args;
15076 tree parms = TREE_VALUE (t);
15078 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t));
15083 ++processing_template_decl;
15085 /* Discard the outer levels of args, and then substitute in the
15086 template args from the enclosing class. */
15087 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args);
15088 partial_spec_args = tsubst_template_args
15089 (partial_spec_args, outer_args, tf_none, NULL_TREE);
15091 /* PARMS already refers to just the innermost parms, but the
15092 template parms in partial_spec_args had their levels lowered
15093 by tsubst, so we need to do the same for the parm list. We
15094 can't just tsubst the TREE_VEC itself, as tsubst wants to
15095 treat a TREE_VEC as an argument vector. */
15096 parms = copy_node (parms);
15097 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i)
15098 TREE_VEC_ELT (parms, i) =
15099 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE);
15101 --processing_template_decl;
15103 spec_args = get_class_bindings (parms,
15109 spec_args = add_to_template_args (outer_args, spec_args);
15110 list = tree_cons (spec_args, TREE_VALUE (t), list);
15111 TREE_TYPE (list) = TREE_TYPE (t);
15118 ambiguous_p = false;
15121 t = TREE_CHAIN (t);
15122 for (; t; t = TREE_CHAIN (t))
15124 fate = more_specialized_class (champ, t);
15131 t = TREE_CHAIN (t);
15134 ambiguous_p = true;
15143 for (t = list; t && t != champ; t = TREE_CHAIN (t))
15145 fate = more_specialized_class (champ, t);
15148 ambiguous_p = true;
15155 const char *str = "candidates are:";
15156 error ("ambiguous class template instantiation for %q#T", type);
15157 for (t = list; t; t = TREE_CHAIN (t))
15159 error ("%s %+#T", str, TREE_TYPE (t));
15162 return error_mark_node;
15168 /* Explicitly instantiate DECL. */
15171 do_decl_instantiation (tree decl, tree storage)
15173 tree result = NULL_TREE;
15176 if (!decl || decl == error_mark_node)
15177 /* An error occurred, for which grokdeclarator has already issued
15178 an appropriate message. */
15180 else if (! DECL_LANG_SPECIFIC (decl))
15182 error ("explicit instantiation of non-template %q#D", decl);
15185 else if (TREE_CODE (decl) == VAR_DECL)
15187 /* There is an asymmetry here in the way VAR_DECLs and
15188 FUNCTION_DECLs are handled by grokdeclarator. In the case of
15189 the latter, the DECL we get back will be marked as a
15190 template instantiation, and the appropriate
15191 DECL_TEMPLATE_INFO will be set up. This does not happen for
15192 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
15193 should handle VAR_DECLs as it currently handles
15195 if (!DECL_CLASS_SCOPE_P (decl))
15197 error ("%qD is not a static data member of a class template", decl);
15200 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
15201 if (!result || TREE_CODE (result) != VAR_DECL)
15203 error ("no matching template for %qD found", decl);
15206 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl)))
15208 error ("type %qT for explicit instantiation %qD does not match "
15209 "declared type %qT", TREE_TYPE (result), decl,
15214 else if (TREE_CODE (decl) != FUNCTION_DECL)
15216 error ("explicit instantiation of %q#D", decl);
15222 /* Check for various error cases. Note that if the explicit
15223 instantiation is valid the RESULT will currently be marked as an
15224 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
15225 until we get here. */
15227 if (DECL_TEMPLATE_SPECIALIZATION (result))
15229 /* DR 259 [temp.spec].
15231 Both an explicit instantiation and a declaration of an explicit
15232 specialization shall not appear in a program unless the explicit
15233 instantiation follows a declaration of the explicit specialization.
15235 For a given set of template parameters, if an explicit
15236 instantiation of a template appears after a declaration of an
15237 explicit specialization for that template, the explicit
15238 instantiation has no effect. */
15241 else if (DECL_EXPLICIT_INSTANTIATION (result))
15245 No program shall explicitly instantiate any template more
15248 We check DECL_NOT_REALLY_EXTERN so as not to complain when
15249 the first instantiation was `extern' and the second is not,
15250 and EXTERN_P for the opposite case. */
15251 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
15252 permerror (input_location, "duplicate explicit instantiation of %q#D", result);
15253 /* If an "extern" explicit instantiation follows an ordinary
15254 explicit instantiation, the template is instantiated. */
15258 else if (!DECL_IMPLICIT_INSTANTIATION (result))
15260 error ("no matching template for %qD found", result);
15263 else if (!DECL_TEMPLATE_INFO (result))
15265 permerror (input_location, "explicit instantiation of non-template %q#D", result);
15269 if (storage == NULL_TREE)
15271 else if (storage == ridpointers[(int) RID_EXTERN])
15273 if (!in_system_header && (cxx_dialect == cxx98))
15274 pedwarn (input_location, OPT_pedantic,
15275 "ISO C++ 1998 forbids the use of %<extern%> on explicit "
15280 error ("storage class %qD applied to template instantiation", storage);
15282 check_explicit_instantiation_namespace (result);
15283 mark_decl_instantiated (result, extern_p);
15285 instantiate_decl (result, /*defer_ok=*/1,
15286 /*expl_inst_class_mem_p=*/false);
15290 mark_class_instantiated (tree t, int extern_p)
15292 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
15293 SET_CLASSTYPE_INTERFACE_KNOWN (t);
15294 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
15295 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
15298 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
15299 rest_of_type_compilation (t, 1);
15303 /* Called from do_type_instantiation through binding_table_foreach to
15304 do recursive instantiation for the type bound in ENTRY. */
15306 bt_instantiate_type_proc (binding_entry entry, void *data)
15308 tree storage = *(tree *) data;
15310 if (MAYBE_CLASS_TYPE_P (entry->type)
15311 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
15312 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
15315 /* Called from do_type_instantiation to instantiate a member
15316 (a member function or a static member variable) of an
15317 explicitly instantiated class template. */
15319 instantiate_class_member (tree decl, int extern_p)
15321 mark_decl_instantiated (decl, extern_p);
15323 instantiate_decl (decl, /*defer_ok=*/1,
15324 /*expl_inst_class_mem_p=*/true);
15327 /* Perform an explicit instantiation of template class T. STORAGE, if
15328 non-null, is the RID for extern, inline or static. COMPLAIN is
15329 nonzero if this is called from the parser, zero if called recursively,
15330 since the standard is unclear (as detailed below). */
15333 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
15338 int previous_instantiation_extern_p = 0;
15340 if (TREE_CODE (t) == TYPE_DECL)
15343 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
15345 error ("explicit instantiation of non-template type %qT", t);
15351 if (!COMPLETE_TYPE_P (t))
15353 if (complain & tf_error)
15354 error ("explicit instantiation of %q#T before definition of template",
15359 if (storage != NULL_TREE)
15361 if (!in_system_header)
15363 if (storage == ridpointers[(int) RID_EXTERN])
15365 if (cxx_dialect == cxx98)
15366 pedwarn (input_location, OPT_pedantic,
15367 "ISO C++ 1998 forbids the use of %<extern%> on "
15368 "explicit instantiations");
15371 pedwarn (input_location, OPT_pedantic,
15372 "ISO C++ forbids the use of %qE"
15373 " on explicit instantiations", storage);
15376 if (storage == ridpointers[(int) RID_INLINE])
15378 else if (storage == ridpointers[(int) RID_EXTERN])
15380 else if (storage == ridpointers[(int) RID_STATIC])
15384 error ("storage class %qD applied to template instantiation",
15390 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
15392 /* DR 259 [temp.spec].
15394 Both an explicit instantiation and a declaration of an explicit
15395 specialization shall not appear in a program unless the explicit
15396 instantiation follows a declaration of the explicit specialization.
15398 For a given set of template parameters, if an explicit
15399 instantiation of a template appears after a declaration of an
15400 explicit specialization for that template, the explicit
15401 instantiation has no effect. */
15404 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
15408 No program shall explicitly instantiate any template more
15411 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
15412 instantiation was `extern'. If EXTERN_P then the second is.
15413 These cases are OK. */
15414 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
15416 if (!previous_instantiation_extern_p && !extern_p
15417 && (complain & tf_error))
15418 permerror (input_location, "duplicate explicit instantiation of %q#T", t);
15420 /* If we've already instantiated the template, just return now. */
15421 if (!CLASSTYPE_INTERFACE_ONLY (t))
15425 check_explicit_instantiation_namespace (TYPE_NAME (t));
15426 mark_class_instantiated (t, extern_p);
15434 /* In contrast to implicit instantiation, where only the
15435 declarations, and not the definitions, of members are
15436 instantiated, we have here:
15440 The explicit instantiation of a class template specialization
15441 implies the instantiation of all of its members not
15442 previously explicitly specialized in the translation unit
15443 containing the explicit instantiation.
15445 Of course, we can't instantiate member template classes, since
15446 we don't have any arguments for them. Note that the standard
15447 is unclear on whether the instantiation of the members are
15448 *explicit* instantiations or not. However, the most natural
15449 interpretation is that it should be an explicit instantiation. */
15452 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
15453 if (TREE_CODE (tmp) == FUNCTION_DECL
15454 && DECL_TEMPLATE_INSTANTIATION (tmp))
15455 instantiate_class_member (tmp, extern_p);
15457 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
15458 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
15459 instantiate_class_member (tmp, extern_p);
15461 if (CLASSTYPE_NESTED_UTDS (t))
15462 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
15463 bt_instantiate_type_proc, &storage);
15467 /* Given a function DECL, which is a specialization of TMPL, modify
15468 DECL to be a re-instantiation of TMPL with the same template
15469 arguments. TMPL should be the template into which tsubst'ing
15470 should occur for DECL, not the most general template.
15472 One reason for doing this is a scenario like this:
15475 void f(const T&, int i);
15477 void g() { f(3, 7); }
15480 void f(const T& t, const int i) { }
15482 Note that when the template is first instantiated, with
15483 instantiate_template, the resulting DECL will have no name for the
15484 first parameter, and the wrong type for the second. So, when we go
15485 to instantiate the DECL, we regenerate it. */
15488 regenerate_decl_from_template (tree decl, tree tmpl)
15490 /* The arguments used to instantiate DECL, from the most general
15495 args = DECL_TI_ARGS (decl);
15496 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
15498 /* Make sure that we can see identifiers, and compute access
15500 push_access_scope (decl);
15502 if (TREE_CODE (decl) == FUNCTION_DECL)
15510 args_depth = TMPL_ARGS_DEPTH (args);
15511 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
15512 if (args_depth > parms_depth)
15513 args = get_innermost_template_args (args, parms_depth);
15515 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
15516 args, tf_error, NULL_TREE);
15518 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
15521 /* Merge parameter declarations. */
15522 decl_parm = skip_artificial_parms_for (decl,
15523 DECL_ARGUMENTS (decl));
15525 = skip_artificial_parms_for (code_pattern,
15526 DECL_ARGUMENTS (code_pattern));
15527 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm))
15532 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
15533 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
15534 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
15536 parm_type = type_decays_to (parm_type);
15537 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
15538 TREE_TYPE (decl_parm) = parm_type;
15539 attributes = DECL_ATTRIBUTES (pattern_parm);
15540 if (DECL_ATTRIBUTES (decl_parm) != attributes)
15542 DECL_ATTRIBUTES (decl_parm) = attributes;
15543 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
15545 decl_parm = TREE_CHAIN (decl_parm);
15546 pattern_parm = TREE_CHAIN (pattern_parm);
15548 /* Merge any parameters that match with the function parameter
15550 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm))
15553 tree expanded_types;
15554 /* Expand the TYPE_PACK_EXPANSION that provides the types for
15555 the parameters in this function parameter pack. */
15556 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm),
15557 args, tf_error, NULL_TREE);
15558 len = TREE_VEC_LENGTH (expanded_types);
15559 for (i = 0; i < len; i++)
15564 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
15565 /* Rename the parameter to include the index. */
15566 DECL_NAME (decl_parm) =
15567 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i);
15568 parm_type = TREE_VEC_ELT (expanded_types, i);
15569 parm_type = type_decays_to (parm_type);
15570 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
15571 TREE_TYPE (decl_parm) = parm_type;
15572 attributes = DECL_ATTRIBUTES (pattern_parm);
15573 if (DECL_ATTRIBUTES (decl_parm) != attributes)
15575 DECL_ATTRIBUTES (decl_parm) = attributes;
15576 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
15578 decl_parm = TREE_CHAIN (decl_parm);
15581 /* Merge additional specifiers from the CODE_PATTERN. */
15582 if (DECL_DECLARED_INLINE_P (code_pattern)
15583 && !DECL_DECLARED_INLINE_P (decl))
15584 DECL_DECLARED_INLINE_P (decl) = 1;
15586 else if (TREE_CODE (decl) == VAR_DECL)
15587 DECL_INITIAL (decl) =
15588 tsubst_expr (DECL_INITIAL (code_pattern), args,
15589 tf_error, DECL_TI_TEMPLATE (decl),
15590 /*integral_constant_expression_p=*/false);
15592 gcc_unreachable ();
15594 pop_access_scope (decl);
15597 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
15598 substituted to get DECL. */
15601 template_for_substitution (tree decl)
15603 tree tmpl = DECL_TI_TEMPLATE (decl);
15605 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
15606 for the instantiation. This is not always the most general
15607 template. Consider, for example:
15610 struct S { template <class U> void f();
15611 template <> void f<int>(); };
15613 and an instantiation of S<double>::f<int>. We want TD to be the
15614 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
15615 while (/* An instantiation cannot have a definition, so we need a
15616 more general template. */
15617 DECL_TEMPLATE_INSTANTIATION (tmpl)
15618 /* We must also deal with friend templates. Given:
15620 template <class T> struct S {
15621 template <class U> friend void f() {};
15624 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
15625 so far as the language is concerned, but that's still
15626 where we get the pattern for the instantiation from. On
15627 other hand, if the definition comes outside the class, say:
15629 template <class T> struct S {
15630 template <class U> friend void f();
15632 template <class U> friend void f() {}
15634 we don't need to look any further. That's what the check for
15635 DECL_INITIAL is for. */
15636 || (TREE_CODE (decl) == FUNCTION_DECL
15637 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
15638 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
15640 /* The present template, TD, should not be a definition. If it
15641 were a definition, we should be using it! Note that we
15642 cannot restructure the loop to just keep going until we find
15643 a template with a definition, since that might go too far if
15644 a specialization was declared, but not defined. */
15645 gcc_assert (TREE_CODE (decl) != VAR_DECL
15646 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
15648 /* Fetch the more general template. */
15649 tmpl = DECL_TI_TEMPLATE (tmpl);
15655 /* Produce the definition of D, a _DECL generated from a template. If
15656 DEFER_OK is nonzero, then we don't have to actually do the
15657 instantiation now; we just have to do it sometime. Normally it is
15658 an error if this is an explicit instantiation but D is undefined.
15659 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
15660 explicitly instantiated class template. */
15663 instantiate_decl (tree d, int defer_ok,
15664 bool expl_inst_class_mem_p)
15666 tree tmpl = DECL_TI_TEMPLATE (d);
15673 bool pattern_defined;
15675 location_t saved_loc = input_location;
15678 /* This function should only be used to instantiate templates for
15679 functions and static member variables. */
15680 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
15681 || TREE_CODE (d) == VAR_DECL);
15683 /* Variables are never deferred; if instantiation is required, they
15684 are instantiated right away. That allows for better code in the
15685 case that an expression refers to the value of the variable --
15686 if the variable has a constant value the referring expression can
15687 take advantage of that fact. */
15688 if (TREE_CODE (d) == VAR_DECL)
15691 /* Don't instantiate cloned functions. Instead, instantiate the
15692 functions they cloned. */
15693 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
15694 d = DECL_CLONED_FUNCTION (d);
15696 if (DECL_TEMPLATE_INSTANTIATED (d)
15697 || DECL_TEMPLATE_SPECIALIZATION (d))
15698 /* D has already been instantiated or explicitly specialized, so
15699 there's nothing for us to do here.
15701 It might seem reasonable to check whether or not D is an explicit
15702 instantiation, and, if so, stop here. But when an explicit
15703 instantiation is deferred until the end of the compilation,
15704 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do
15705 the instantiation. */
15708 gen_tmpl = most_general_template (tmpl);
15709 gen_args = DECL_TI_ARGS (d);
15711 if (tmpl != gen_tmpl)
15712 /* We should already have the extra args. */
15713 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl))
15714 == TMPL_ARGS_DEPTH (gen_args));
15715 /* And what's in the hash table should match D. */
15716 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d
15717 || spec == NULL_TREE);
15719 /* This needs to happen before any tsubsting. */
15720 if (! push_tinst_level (d))
15723 timevar_push (TV_PARSE);
15725 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
15726 for the instantiation. */
15727 td = template_for_substitution (d);
15728 code_pattern = DECL_TEMPLATE_RESULT (td);
15730 /* We should never be trying to instantiate a member of a class
15731 template or partial specialization. */
15732 gcc_assert (d != code_pattern);
15734 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
15735 || DECL_TEMPLATE_SPECIALIZATION (td))
15736 /* In the case of a friend template whose definition is provided
15737 outside the class, we may have too many arguments. Drop the
15738 ones we don't need. The same is true for specializations. */
15739 args = get_innermost_template_args
15740 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
15744 if (TREE_CODE (d) == FUNCTION_DECL)
15745 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
15747 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
15749 /* We may be in the middle of deferred access check. Disable it now. */
15750 push_deferring_access_checks (dk_no_deferred);
15752 /* Unless an explicit instantiation directive has already determined
15753 the linkage of D, remember that a definition is available for
15755 if (pattern_defined
15756 && !DECL_INTERFACE_KNOWN (d)
15757 && !DECL_NOT_REALLY_EXTERN (d))
15758 mark_definable (d);
15760 input_location = DECL_SOURCE_LOCATION (d);
15762 /* If D is a member of an explicitly instantiated class template,
15763 and no definition is available, treat it like an implicit
15765 if (!pattern_defined && expl_inst_class_mem_p
15766 && DECL_EXPLICIT_INSTANTIATION (d))
15768 DECL_NOT_REALLY_EXTERN (d) = 0;
15769 DECL_INTERFACE_KNOWN (d) = 0;
15770 SET_DECL_IMPLICIT_INSTANTIATION (d);
15775 /* Recheck the substitutions to obtain any warning messages
15776 about ignoring cv qualifiers. */
15777 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
15778 tree type = TREE_TYPE (gen);
15780 /* Make sure that we can see identifiers, and compute access
15781 correctly. D is already the target FUNCTION_DECL with the
15783 push_access_scope (d);
15785 if (TREE_CODE (gen) == FUNCTION_DECL)
15787 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d);
15788 tsubst_exception_specification (type, gen_args, tf_warning_or_error,
15790 /* Don't simply tsubst the function type, as that will give
15791 duplicate warnings about poor parameter qualifications.
15792 The function arguments are the same as the decl_arguments
15793 without the top level cv qualifiers. */
15794 type = TREE_TYPE (type);
15796 tsubst (type, gen_args, tf_warning_or_error, d);
15798 pop_access_scope (d);
15801 /* Check to see whether we know that this template will be
15802 instantiated in some other file, as with "extern template"
15804 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
15805 /* In general, we do not instantiate such templates... */
15807 /* ... but we instantiate inline functions so that we can inline
15808 them. An explicit instantiation declaration prohibits implicit
15809 instantiation of non-inline functions. With high levels of
15810 optimization, we would normally inline non-inline functions
15811 -- but we're not allowed to do that for "extern template" functions.
15812 Therefore, we check DECL_DECLARED_INLINE_P, rather than
15813 possibly_inlined_p. And ... */
15814 && ! (TREE_CODE (d) == FUNCTION_DECL
15815 && DECL_DECLARED_INLINE_P (d))
15816 /* ... we instantiate static data members whose values are
15817 needed in integral constant expressions. */
15818 && ! (TREE_CODE (d) == VAR_DECL
15819 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
15821 /* Defer all other templates, unless we have been explicitly
15822 forbidden from doing so. */
15823 if (/* If there is no definition, we cannot instantiate the
15826 /* If it's OK to postpone instantiation, do so. */
15828 /* If this is a static data member that will be defined
15829 elsewhere, we don't want to instantiate the entire data
15830 member, but we do want to instantiate the initializer so that
15831 we can substitute that elsewhere. */
15832 || (external_p && TREE_CODE (d) == VAR_DECL))
15834 /* The definition of the static data member is now required so
15835 we must substitute the initializer. */
15836 if (TREE_CODE (d) == VAR_DECL
15837 && !DECL_INITIAL (d)
15838 && DECL_INITIAL (code_pattern))
15843 ns = decl_namespace_context (d);
15844 push_nested_namespace (ns);
15845 push_nested_class (DECL_CONTEXT (d));
15846 init = tsubst_expr (DECL_INITIAL (code_pattern),
15848 tf_warning_or_error, NULL_TREE,
15849 /*integral_constant_expression_p=*/false);
15850 cp_finish_decl (d, init, /*init_const_expr_p=*/false,
15851 /*asmspec_tree=*/NULL_TREE,
15852 LOOKUP_ONLYCONVERTING);
15853 pop_nested_class ();
15854 pop_nested_namespace (ns);
15857 /* We restore the source position here because it's used by
15858 add_pending_template. */
15859 input_location = saved_loc;
15861 if (at_eof && !pattern_defined
15862 && DECL_EXPLICIT_INSTANTIATION (d)
15863 && DECL_NOT_REALLY_EXTERN (d))
15866 The definition of a non-exported function template, a
15867 non-exported member function template, or a non-exported
15868 member function or static data member of a class template
15869 shall be present in every translation unit in which it is
15870 explicitly instantiated. */
15871 permerror (input_location, "explicit instantiation of %qD "
15872 "but no definition available", d);
15874 /* ??? Historically, we have instantiated inline functions, even
15875 when marked as "extern template". */
15876 if (!(external_p && TREE_CODE (d) == VAR_DECL))
15877 add_pending_template (d);
15880 /* Tell the repository that D is available in this translation unit
15881 -- and see if it is supposed to be instantiated here. */
15882 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
15884 /* In a PCH file, despite the fact that the repository hasn't
15885 requested instantiation in the PCH it is still possible that
15886 an instantiation will be required in a file that includes the
15889 add_pending_template (d);
15890 /* Instantiate inline functions so that the inliner can do its
15891 job, even though we'll not be emitting a copy of this
15893 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d)))
15897 need_push = !cfun || !global_bindings_p ();
15899 push_to_top_level ();
15901 /* Mark D as instantiated so that recursive calls to
15902 instantiate_decl do not try to instantiate it again. */
15903 DECL_TEMPLATE_INSTANTIATED (d) = 1;
15905 /* Regenerate the declaration in case the template has been modified
15906 by a subsequent redeclaration. */
15907 regenerate_decl_from_template (d, td);
15909 /* We already set the file and line above. Reset them now in case
15910 they changed as a result of calling regenerate_decl_from_template. */
15911 input_location = DECL_SOURCE_LOCATION (d);
15913 if (TREE_CODE (d) == VAR_DECL)
15917 /* Clear out DECL_RTL; whatever was there before may not be right
15918 since we've reset the type of the declaration. */
15919 SET_DECL_RTL (d, NULL_RTX);
15920 DECL_IN_AGGR_P (d) = 0;
15922 /* The initializer is placed in DECL_INITIAL by
15923 regenerate_decl_from_template. Pull it out so that
15924 cp_finish_decl can process it. */
15925 init = DECL_INITIAL (d);
15926 DECL_INITIAL (d) = NULL_TREE;
15927 DECL_INITIALIZED_P (d) = 0;
15929 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
15930 initializer. That function will defer actual emission until
15931 we have a chance to determine linkage. */
15932 DECL_EXTERNAL (d) = 0;
15934 /* Enter the scope of D so that access-checking works correctly. */
15935 push_nested_class (DECL_CONTEXT (d));
15936 cp_finish_decl (d, init, false, NULL_TREE, 0);
15937 pop_nested_class ();
15939 else if (TREE_CODE (d) == FUNCTION_DECL)
15941 htab_t saved_local_specializations;
15946 /* Save away the current list, in case we are instantiating one
15947 template from within the body of another. */
15948 saved_local_specializations = local_specializations;
15950 /* Set up the list of local specializations. */
15951 local_specializations = htab_create (37,
15952 hash_local_specialization,
15953 eq_local_specializations,
15956 /* Set up context. */
15957 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
15959 /* Create substitution entries for the parameters. */
15960 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
15961 tmpl_parm = DECL_ARGUMENTS (subst_decl);
15962 spec_parm = DECL_ARGUMENTS (d);
15963 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
15965 register_local_specialization (spec_parm, tmpl_parm);
15966 spec_parm = skip_artificial_parms_for (d, spec_parm);
15967 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
15969 while (tmpl_parm && !FUNCTION_PARAMETER_PACK_P (tmpl_parm))
15971 register_local_specialization (spec_parm, tmpl_parm);
15972 tmpl_parm = TREE_CHAIN (tmpl_parm);
15973 spec_parm = TREE_CHAIN (spec_parm);
15975 if (tmpl_parm && FUNCTION_PARAMETER_PACK_P (tmpl_parm))
15977 /* Register the (value) argument pack as a specialization of
15978 TMPL_PARM, then move on. */
15979 tree argpack = make_fnparm_pack (spec_parm);
15980 register_local_specialization (argpack, tmpl_parm);
15981 tmpl_parm = TREE_CHAIN (tmpl_parm);
15982 spec_parm = NULL_TREE;
15984 gcc_assert (!spec_parm);
15986 /* Substitute into the body of the function. */
15987 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
15988 tf_warning_or_error, tmpl,
15989 /*integral_constant_expression_p=*/false);
15991 /* Set the current input_location to the end of the function
15992 so that finish_function knows where we are. */
15993 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus;
15995 /* We don't need the local specializations any more. */
15996 htab_delete (local_specializations);
15997 local_specializations = saved_local_specializations;
15999 /* Finish the function. */
16000 d = finish_function (0);
16001 expand_or_defer_fn (d);
16004 /* We're not deferring instantiation any more. */
16005 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
16008 pop_from_top_level ();
16011 input_location = saved_loc;
16012 pop_deferring_access_checks ();
16013 pop_tinst_level ();
16015 timevar_pop (TV_PARSE);
16020 /* Run through the list of templates that we wish we could
16021 instantiate, and instantiate any we can. RETRIES is the
16022 number of times we retry pending template instantiation. */
16025 instantiate_pending_templates (int retries)
16028 location_t saved_loc = input_location;
16030 /* Instantiating templates may trigger vtable generation. This in turn
16031 may require further template instantiations. We place a limit here
16032 to avoid infinite loop. */
16033 if (pending_templates && retries >= max_tinst_depth)
16035 tree decl = pending_templates->tinst->decl;
16037 error ("template instantiation depth exceeds maximum of %d"
16038 " instantiating %q+D, possibly from virtual table generation"
16039 " (use -ftemplate-depth-NN to increase the maximum)",
16040 max_tinst_depth, decl);
16041 if (TREE_CODE (decl) == FUNCTION_DECL)
16042 /* Pretend that we defined it. */
16043 DECL_INITIAL (decl) = error_mark_node;
16049 struct pending_template **t = &pending_templates;
16050 struct pending_template *last = NULL;
16054 tree instantiation = reopen_tinst_level ((*t)->tinst);
16055 bool complete = false;
16057 if (TYPE_P (instantiation))
16061 if (!COMPLETE_TYPE_P (instantiation))
16063 instantiate_class_template (instantiation);
16064 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
16065 for (fn = TYPE_METHODS (instantiation);
16067 fn = TREE_CHAIN (fn))
16068 if (! DECL_ARTIFICIAL (fn))
16069 instantiate_decl (fn,
16071 /*expl_inst_class_mem_p=*/false);
16072 if (COMPLETE_TYPE_P (instantiation))
16076 complete = COMPLETE_TYPE_P (instantiation);
16080 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
16081 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
16084 = instantiate_decl (instantiation,
16086 /*expl_inst_class_mem_p=*/false);
16087 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
16091 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation)
16092 || DECL_TEMPLATE_INSTANTIATED (instantiation));
16096 /* If INSTANTIATION has been instantiated, then we don't
16097 need to consider it again in the future. */
16105 current_tinst_level = NULL;
16107 last_pending_template = last;
16109 while (reconsider);
16111 input_location = saved_loc;
16114 /* Substitute ARGVEC into T, which is a list of initializers for
16115 either base class or a non-static data member. The TREE_PURPOSEs
16116 are DECLs, and the TREE_VALUEs are the initializer values. Used by
16117 instantiate_decl. */
16120 tsubst_initializer_list (tree t, tree argvec)
16122 tree inits = NULL_TREE;
16124 for (; t; t = TREE_CHAIN (t))
16128 tree expanded_bases = NULL_TREE;
16129 tree expanded_arguments = NULL_TREE;
16132 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION)
16137 /* Expand the base class expansion type into separate base
16139 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec,
16140 tf_warning_or_error,
16142 if (expanded_bases == error_mark_node)
16145 /* We'll be building separate TREE_LISTs of arguments for
16147 len = TREE_VEC_LENGTH (expanded_bases);
16148 expanded_arguments = make_tree_vec (len);
16149 for (i = 0; i < len; i++)
16150 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE;
16152 /* Build a dummy EXPR_PACK_EXPANSION that will be used to
16153 expand each argument in the TREE_VALUE of t. */
16154 expr = make_node (EXPR_PACK_EXPANSION);
16155 PACK_EXPANSION_PARAMETER_PACKS (expr) =
16156 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t));
16158 if (TREE_VALUE (t) == void_type_node)
16159 /* VOID_TYPE_NODE is used to indicate
16160 value-initialization. */
16162 for (i = 0; i < len; i++)
16163 TREE_VEC_ELT (expanded_arguments, i) = void_type_node;
16167 /* Substitute parameter packs into each argument in the
16169 in_base_initializer = 1;
16170 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg))
16172 tree expanded_exprs;
16174 /* Expand the argument. */
16175 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg));
16177 = tsubst_pack_expansion (expr, argvec,
16178 tf_warning_or_error,
16180 if (expanded_exprs == error_mark_node)
16183 /* Prepend each of the expanded expressions to the
16184 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */
16185 for (i = 0; i < len; i++)
16187 TREE_VEC_ELT (expanded_arguments, i) =
16188 tree_cons (NULL_TREE,
16189 TREE_VEC_ELT (expanded_exprs, i),
16190 TREE_VEC_ELT (expanded_arguments, i));
16193 in_base_initializer = 0;
16195 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS,
16196 since we built them backwards. */
16197 for (i = 0; i < len; i++)
16199 TREE_VEC_ELT (expanded_arguments, i) =
16200 nreverse (TREE_VEC_ELT (expanded_arguments, i));
16205 for (i = 0; i < len; ++i)
16207 if (expanded_bases)
16209 decl = TREE_VEC_ELT (expanded_bases, i);
16210 decl = expand_member_init (decl);
16211 init = TREE_VEC_ELT (expanded_arguments, i);
16215 decl = tsubst_copy (TREE_PURPOSE (t), argvec,
16216 tf_warning_or_error, NULL_TREE);
16218 decl = expand_member_init (decl);
16219 if (decl && !DECL_P (decl))
16220 in_base_initializer = 1;
16222 init = tsubst_expr (TREE_VALUE (t), argvec,
16223 tf_warning_or_error, NULL_TREE,
16224 /*integral_constant_expression_p=*/false);
16225 in_base_initializer = 0;
16230 init = build_tree_list (decl, init);
16231 TREE_CHAIN (init) = inits;
16239 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
16242 set_current_access_from_decl (tree decl)
16244 if (TREE_PRIVATE (decl))
16245 current_access_specifier = access_private_node;
16246 else if (TREE_PROTECTED (decl))
16247 current_access_specifier = access_protected_node;
16249 current_access_specifier = access_public_node;
16252 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
16253 is the instantiation (which should have been created with
16254 start_enum) and ARGS are the template arguments to use. */
16257 tsubst_enum (tree tag, tree newtag, tree args)
16261 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
16266 decl = TREE_VALUE (e);
16267 /* Note that in a template enum, the TREE_VALUE is the
16268 CONST_DECL, not the corresponding INTEGER_CST. */
16269 value = tsubst_expr (DECL_INITIAL (decl),
16270 args, tf_warning_or_error, NULL_TREE,
16271 /*integral_constant_expression_p=*/true);
16273 /* Give this enumeration constant the correct access. */
16274 set_current_access_from_decl (decl);
16276 /* Actually build the enumerator itself. */
16277 build_enumerator (DECL_NAME (decl), value, newtag);
16280 finish_enum (newtag);
16281 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
16282 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
16285 /* DECL is a FUNCTION_DECL that is a template specialization. Return
16286 its type -- but without substituting the innermost set of template
16287 arguments. So, innermost set of template parameters will appear in
16291 get_mostly_instantiated_function_type (tree decl)
16299 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
16300 targs = DECL_TI_ARGS (decl);
16301 tparms = DECL_TEMPLATE_PARMS (tmpl);
16302 parm_depth = TMPL_PARMS_DEPTH (tparms);
16304 /* There should be as many levels of arguments as there are levels
16306 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
16308 fn_type = TREE_TYPE (tmpl);
16310 if (parm_depth == 1)
16311 /* No substitution is necessary. */
16315 int i, save_access_control;
16318 /* Replace the innermost level of the TARGS with NULL_TREEs to
16319 let tsubst know not to substitute for those parameters. */
16320 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
16321 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
16322 SET_TMPL_ARGS_LEVEL (partial_args, i,
16323 TMPL_ARGS_LEVEL (targs, i));
16324 SET_TMPL_ARGS_LEVEL (partial_args,
16325 TMPL_ARGS_DEPTH (targs),
16326 make_tree_vec (DECL_NTPARMS (tmpl)));
16328 /* Disable access control as this function is used only during
16330 save_access_control = flag_access_control;
16331 flag_access_control = 0;
16333 ++processing_template_decl;
16334 /* Now, do the (partial) substitution to figure out the
16335 appropriate function type. */
16336 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
16337 --processing_template_decl;
16339 /* Substitute into the template parameters to obtain the real
16340 innermost set of parameters. This step is important if the
16341 innermost set of template parameters contains value
16342 parameters whose types depend on outer template parameters. */
16343 TREE_VEC_LENGTH (partial_args)--;
16344 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
16346 flag_access_control = save_access_control;
16352 /* Return truthvalue if we're processing a template different from
16353 the last one involved in diagnostics. */
16355 problematic_instantiation_changed (void)
16357 return last_template_error_tick != tinst_level_tick;
16360 /* Remember current template involved in diagnostics. */
16362 record_last_problematic_instantiation (void)
16364 last_template_error_tick = tinst_level_tick;
16367 struct tinst_level *
16368 current_instantiation (void)
16370 return current_tinst_level;
16373 /* [temp.param] Check that template non-type parm TYPE is of an allowable
16374 type. Return zero for ok, nonzero for disallowed. Issue error and
16375 warning messages under control of COMPLAIN. */
16378 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
16380 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type))
16382 else if (POINTER_TYPE_P (type))
16384 else if (TYPE_PTR_TO_MEMBER_P (type))
16386 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
16388 else if (TREE_CODE (type) == TYPENAME_TYPE)
16391 if (complain & tf_error)
16392 error ("%q#T is not a valid type for a template constant parameter", type);
16396 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
16397 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
16400 dependent_type_p_r (tree type)
16406 A type is dependent if it is:
16408 -- a template parameter. Template template parameters are types
16409 for us (since TYPE_P holds true for them) so we handle
16411 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
16412 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
16414 /* -- a qualified-id with a nested-name-specifier which contains a
16415 class-name that names a dependent type or whose unqualified-id
16416 names a dependent type. */
16417 if (TREE_CODE (type) == TYPENAME_TYPE)
16419 /* -- a cv-qualified type where the cv-unqualified type is
16421 type = TYPE_MAIN_VARIANT (type);
16422 /* -- a compound type constructed from any dependent type. */
16423 if (TYPE_PTR_TO_MEMBER_P (type))
16424 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
16425 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
16427 else if (TREE_CODE (type) == POINTER_TYPE
16428 || TREE_CODE (type) == REFERENCE_TYPE)
16429 return dependent_type_p (TREE_TYPE (type));
16430 else if (TREE_CODE (type) == FUNCTION_TYPE
16431 || TREE_CODE (type) == METHOD_TYPE)
16435 if (dependent_type_p (TREE_TYPE (type)))
16437 for (arg_type = TYPE_ARG_TYPES (type);
16439 arg_type = TREE_CHAIN (arg_type))
16440 if (dependent_type_p (TREE_VALUE (arg_type)))
16444 /* -- an array type constructed from any dependent type or whose
16445 size is specified by a constant expression that is
16446 value-dependent. */
16447 if (TREE_CODE (type) == ARRAY_TYPE)
16449 if (TYPE_DOMAIN (type)
16450 && dependent_type_p (TYPE_DOMAIN (type)))
16452 return dependent_type_p (TREE_TYPE (type));
16454 else if (TREE_CODE (type) == INTEGER_TYPE
16455 && !TREE_CONSTANT (TYPE_MAX_VALUE (type)))
16457 /* If this is the TYPE_DOMAIN of an array type, consider it
16458 dependent. We already checked for value-dependence in
16459 compute_array_index_type. */
16460 return type_dependent_expression_p (TYPE_MAX_VALUE (type));
16463 /* -- a template-id in which either the template name is a template
16465 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
16467 /* ... or any of the template arguments is a dependent type or
16468 an expression that is type-dependent or value-dependent. */
16469 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
16470 && (any_dependent_template_arguments_p
16471 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
16474 /* All TYPEOF_TYPEs and DECLTYPE_TYPEs are dependent; if the
16475 argument of the `typeof' expression is not type-dependent, then
16476 it should already been have resolved. */
16477 if (TREE_CODE (type) == TYPEOF_TYPE
16478 || TREE_CODE (type) == DECLTYPE_TYPE)
16481 /* A template argument pack is dependent if any of its packed
16483 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK)
16485 tree args = ARGUMENT_PACK_ARGS (type);
16486 int i, len = TREE_VEC_LENGTH (args);
16487 for (i = 0; i < len; ++i)
16488 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
16492 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must
16493 be template parameters. */
16494 if (TREE_CODE (type) == TYPE_PACK_EXPANSION)
16497 /* The standard does not specifically mention types that are local
16498 to template functions or local classes, but they should be
16499 considered dependent too. For example:
16501 template <int I> void f() {
16506 The size of `E' cannot be known until the value of `I' has been
16507 determined. Therefore, `E' must be considered dependent. */
16508 scope = TYPE_CONTEXT (type);
16509 if (scope && TYPE_P (scope))
16510 return dependent_type_p (scope);
16511 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
16512 return type_dependent_expression_p (scope);
16514 /* Other types are non-dependent. */
16518 /* Returns TRUE if TYPE is dependent, in the sense of
16519 [temp.dep.type]. */
16522 dependent_type_p (tree type)
16524 /* If there are no template parameters in scope, then there can't be
16525 any dependent types. */
16526 if (!processing_template_decl)
16528 /* If we are not processing a template, then nobody should be
16529 providing us with a dependent type. */
16531 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type));
16535 /* If the type is NULL, we have not computed a type for the entity
16536 in question; in that case, the type is dependent. */
16540 /* Erroneous types can be considered non-dependent. */
16541 if (type == error_mark_node)
16544 /* If we have not already computed the appropriate value for TYPE,
16546 if (!TYPE_DEPENDENT_P_VALID (type))
16548 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
16549 TYPE_DEPENDENT_P_VALID (type) = 1;
16552 return TYPE_DEPENDENT_P (type);
16555 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any
16556 lookup. In other words, a dependent type that is not the current
16560 dependent_scope_p (tree scope)
16562 return (scope && TYPE_P (scope) && dependent_type_p (scope)
16563 && !currently_open_class (scope));
16566 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
16569 dependent_scope_ref_p (tree expression, bool criterion (tree))
16574 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
16576 if (!TYPE_P (TREE_OPERAND (expression, 0)))
16579 scope = TREE_OPERAND (expression, 0);
16580 name = TREE_OPERAND (expression, 1);
16584 An id-expression is type-dependent if it contains a
16585 nested-name-specifier that contains a class-name that names a
16587 /* The suggested resolution to Core Issue 224 implies that if the
16588 qualifying type is the current class, then we must peek
16591 && currently_open_class (scope)
16592 && !criterion (name))
16594 if (dependent_type_p (scope))
16600 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
16601 [temp.dep.constexpr]. EXPRESSION is already known to be a constant
16605 value_dependent_expression_p (tree expression)
16607 if (!processing_template_decl)
16610 /* A name declared with a dependent type. */
16611 if (DECL_P (expression) && type_dependent_expression_p (expression))
16614 switch (TREE_CODE (expression))
16616 case IDENTIFIER_NODE:
16617 /* A name that has not been looked up -- must be dependent. */
16620 case TEMPLATE_PARM_INDEX:
16621 /* A non-type template parm. */
16625 /* A non-type template parm. */
16626 if (DECL_TEMPLATE_PARM_P (expression))
16628 return value_dependent_expression_p (DECL_INITIAL (expression));
16631 /* A constant with integral or enumeration type and is initialized
16632 with an expression that is value-dependent. */
16633 if (DECL_INITIAL (expression)
16634 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
16635 && value_dependent_expression_p (DECL_INITIAL (expression)))
16639 case DYNAMIC_CAST_EXPR:
16640 case STATIC_CAST_EXPR:
16641 case CONST_CAST_EXPR:
16642 case REINTERPRET_CAST_EXPR:
16644 /* These expressions are value-dependent if the type to which
16645 the cast occurs is dependent or the expression being casted
16646 is value-dependent. */
16648 tree type = TREE_TYPE (expression);
16650 if (dependent_type_p (type))
16653 /* A functional cast has a list of operands. */
16654 expression = TREE_OPERAND (expression, 0);
16657 /* If there are no operands, it must be an expression such
16658 as "int()". This should not happen for aggregate types
16659 because it would form non-constant expressions. */
16660 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
16665 if (TREE_CODE (expression) == TREE_LIST)
16666 return any_value_dependent_elements_p (expression);
16668 return value_dependent_expression_p (expression);
16673 /* A `sizeof' expression is value-dependent if the operand is
16674 type-dependent or is a pack expansion. */
16675 expression = TREE_OPERAND (expression, 0);
16676 if (PACK_EXPANSION_P (expression))
16678 else if (TYPE_P (expression))
16679 return dependent_type_p (expression);
16680 return type_dependent_expression_p (expression);
16683 return dependent_scope_ref_p (expression, value_dependent_expression_p);
16685 case COMPONENT_REF:
16686 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
16687 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
16690 /* A CALL_EXPR may appear in a constant expression if it is a
16691 call to a builtin function, e.g., __builtin_constant_p. All
16692 such calls are value-dependent. */
16695 case NONTYPE_ARGUMENT_PACK:
16696 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument
16697 is value-dependent. */
16699 tree values = ARGUMENT_PACK_ARGS (expression);
16700 int i, len = TREE_VEC_LENGTH (values);
16702 for (i = 0; i < len; ++i)
16703 if (value_dependent_expression_p (TREE_VEC_ELT (values, i)))
16711 tree type2 = TRAIT_EXPR_TYPE2 (expression);
16712 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression))
16713 || (type2 ? dependent_type_p (type2) : false));
16717 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0)))
16718 || (value_dependent_expression_p (TREE_OPERAND (expression, 2))));
16721 /* A constant expression is value-dependent if any subexpression is
16722 value-dependent. */
16723 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
16725 case tcc_reference:
16727 return (value_dependent_expression_p
16728 (TREE_OPERAND (expression, 0)));
16730 case tcc_comparison:
16732 return ((value_dependent_expression_p
16733 (TREE_OPERAND (expression, 0)))
16734 || (value_dependent_expression_p
16735 (TREE_OPERAND (expression, 1))));
16737 case tcc_expression:
16741 for (i = 0; i < TREE_OPERAND_LENGTH (expression); ++i)
16742 /* In some cases, some of the operands may be missing.
16743 (For example, in the case of PREDECREMENT_EXPR, the
16744 amount to increment by may be missing.) That doesn't
16745 make the expression dependent. */
16746 if (TREE_OPERAND (expression, i)
16747 && (value_dependent_expression_p
16748 (TREE_OPERAND (expression, i))))
16758 /* The expression is not value-dependent. */
16762 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
16763 [temp.dep.expr]. */
16766 type_dependent_expression_p (tree expression)
16768 if (!processing_template_decl)
16771 if (expression == error_mark_node)
16774 /* An unresolved name is always dependent. */
16775 if (TREE_CODE (expression) == IDENTIFIER_NODE
16776 || TREE_CODE (expression) == USING_DECL)
16779 /* Some expression forms are never type-dependent. */
16780 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
16781 || TREE_CODE (expression) == SIZEOF_EXPR
16782 || TREE_CODE (expression) == ALIGNOF_EXPR
16783 || TREE_CODE (expression) == TRAIT_EXPR
16784 || TREE_CODE (expression) == TYPEID_EXPR
16785 || TREE_CODE (expression) == DELETE_EXPR
16786 || TREE_CODE (expression) == VEC_DELETE_EXPR
16787 || TREE_CODE (expression) == THROW_EXPR)
16790 /* The types of these expressions depends only on the type to which
16791 the cast occurs. */
16792 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
16793 || TREE_CODE (expression) == STATIC_CAST_EXPR
16794 || TREE_CODE (expression) == CONST_CAST_EXPR
16795 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
16796 || TREE_CODE (expression) == CAST_EXPR)
16797 return dependent_type_p (TREE_TYPE (expression));
16799 /* The types of these expressions depends only on the type created
16800 by the expression. */
16801 if (TREE_CODE (expression) == NEW_EXPR
16802 || TREE_CODE (expression) == VEC_NEW_EXPR)
16804 /* For NEW_EXPR tree nodes created inside a template, either
16805 the object type itself or a TREE_LIST may appear as the
16807 tree type = TREE_OPERAND (expression, 1);
16808 if (TREE_CODE (type) == TREE_LIST)
16809 /* This is an array type. We need to check array dimensions
16811 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
16812 || value_dependent_expression_p
16813 (TREE_OPERAND (TREE_VALUE (type), 1));
16815 return dependent_type_p (type);
16818 if (TREE_CODE (expression) == SCOPE_REF
16819 && dependent_scope_ref_p (expression,
16820 type_dependent_expression_p))
16823 if (TREE_CODE (expression) == FUNCTION_DECL
16824 && DECL_LANG_SPECIFIC (expression)
16825 && DECL_TEMPLATE_INFO (expression)
16826 && (any_dependent_template_arguments_p
16827 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
16830 if (TREE_CODE (expression) == TEMPLATE_DECL
16831 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
16834 if (TREE_CODE (expression) == STMT_EXPR)
16835 expression = stmt_expr_value_expr (expression);
16837 if (BRACE_ENCLOSED_INITIALIZER_P (expression))
16842 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt)
16844 if (type_dependent_expression_p (elt))
16850 if (TREE_TYPE (expression) == unknown_type_node)
16852 if (TREE_CODE (expression) == ADDR_EXPR)
16853 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
16854 if (TREE_CODE (expression) == COMPONENT_REF
16855 || TREE_CODE (expression) == OFFSET_REF)
16857 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
16859 expression = TREE_OPERAND (expression, 1);
16860 if (TREE_CODE (expression) == IDENTIFIER_NODE)
16863 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
16864 if (TREE_CODE (expression) == SCOPE_REF)
16867 if (TREE_CODE (expression) == BASELINK)
16868 expression = BASELINK_FUNCTIONS (expression);
16870 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
16872 if (any_dependent_template_arguments_p
16873 (TREE_OPERAND (expression, 1)))
16875 expression = TREE_OPERAND (expression, 0);
16877 gcc_assert (TREE_CODE (expression) == OVERLOAD
16878 || TREE_CODE (expression) == FUNCTION_DECL);
16882 if (type_dependent_expression_p (OVL_CURRENT (expression)))
16884 expression = OVL_NEXT (expression);
16889 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
16891 return (dependent_type_p (TREE_TYPE (expression)));
16894 /* Like type_dependent_expression_p, but it also works while not processing
16895 a template definition, i.e. during substitution or mangling. */
16898 type_dependent_expression_p_push (tree expr)
16901 ++processing_template_decl;
16902 b = type_dependent_expression_p (expr);
16903 --processing_template_decl;
16907 /* Returns TRUE if ARGS contains a type-dependent expression. */
16910 any_type_dependent_arguments_p (const VEC(tree,gc) *args)
16915 for (i = 0; VEC_iterate (tree, args, i, arg); ++i)
16917 if (type_dependent_expression_p (arg))
16923 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are
16924 expressions) contains any value-dependent expressions. */
16927 any_value_dependent_elements_p (const_tree list)
16929 for (; list; list = TREE_CHAIN (list))
16930 if (value_dependent_expression_p (TREE_VALUE (list)))
16936 /* Returns TRUE if the ARG (a template argument) is dependent. */
16939 dependent_template_arg_p (tree arg)
16941 if (!processing_template_decl)
16944 if (TREE_CODE (arg) == TEMPLATE_DECL
16945 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
16946 return dependent_template_p (arg);
16947 else if (ARGUMENT_PACK_P (arg))
16949 tree args = ARGUMENT_PACK_ARGS (arg);
16950 int i, len = TREE_VEC_LENGTH (args);
16951 for (i = 0; i < len; ++i)
16953 if (dependent_template_arg_p (TREE_VEC_ELT (args, i)))
16959 else if (TYPE_P (arg))
16960 return dependent_type_p (arg);
16962 return (type_dependent_expression_p (arg)
16963 || value_dependent_expression_p (arg));
16966 /* Returns true if ARGS (a collection of template arguments) contains
16967 any types that require structural equality testing. */
16970 any_template_arguments_need_structural_equality_p (tree args)
16977 if (args == error_mark_node)
16980 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
16982 tree level = TMPL_ARGS_LEVEL (args, i + 1);
16983 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
16985 tree arg = TREE_VEC_ELT (level, j);
16986 tree packed_args = NULL_TREE;
16989 if (ARGUMENT_PACK_P (arg))
16991 /* Look inside the argument pack. */
16992 packed_args = ARGUMENT_PACK_ARGS (arg);
16993 len = TREE_VEC_LENGTH (packed_args);
16996 for (k = 0; k < len; ++k)
16999 arg = TREE_VEC_ELT (packed_args, k);
17001 if (error_operand_p (arg))
17003 else if (TREE_CODE (arg) == TEMPLATE_DECL
17004 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
17006 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg))
17008 else if (!TYPE_P (arg) && TREE_TYPE (arg)
17009 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg)))
17018 /* Returns true if ARGS (a collection of template arguments) contains
17019 any dependent arguments. */
17022 any_dependent_template_arguments_p (const_tree args)
17029 if (args == error_mark_node)
17032 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
17034 const_tree level = TMPL_ARGS_LEVEL (args, i + 1);
17035 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
17036 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
17043 /* Returns TRUE if the template TMPL is dependent. */
17046 dependent_template_p (tree tmpl)
17048 if (TREE_CODE (tmpl) == OVERLOAD)
17052 if (dependent_template_p (OVL_FUNCTION (tmpl)))
17054 tmpl = OVL_CHAIN (tmpl);
17059 /* Template template parameters are dependent. */
17060 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
17061 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
17063 /* So are names that have not been looked up. */
17064 if (TREE_CODE (tmpl) == SCOPE_REF
17065 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
17067 /* So are member templates of dependent classes. */
17068 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
17069 return dependent_type_p (DECL_CONTEXT (tmpl));
17073 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
17076 dependent_template_id_p (tree tmpl, tree args)
17078 return (dependent_template_p (tmpl)
17079 || any_dependent_template_arguments_p (args));
17082 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors
17086 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv)
17090 if (!processing_template_decl)
17093 for (i = 0; i < TREE_VEC_LENGTH (declv); i++)
17095 tree decl = TREE_VEC_ELT (declv, i);
17096 tree init = TREE_VEC_ELT (initv, i);
17097 tree cond = TREE_VEC_ELT (condv, i);
17098 tree incr = TREE_VEC_ELT (incrv, i);
17100 if (type_dependent_expression_p (decl))
17103 if (init && type_dependent_expression_p (init))
17106 if (type_dependent_expression_p (cond))
17109 if (COMPARISON_CLASS_P (cond)
17110 && (type_dependent_expression_p (TREE_OPERAND (cond, 0))
17111 || type_dependent_expression_p (TREE_OPERAND (cond, 1))))
17114 if (TREE_CODE (incr) == MODOP_EXPR)
17116 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))
17117 || type_dependent_expression_p (TREE_OPERAND (incr, 2)))
17120 else if (type_dependent_expression_p (incr))
17122 else if (TREE_CODE (incr) == MODIFY_EXPR)
17124 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)))
17126 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1)))
17128 tree t = TREE_OPERAND (incr, 1);
17129 if (type_dependent_expression_p (TREE_OPERAND (t, 0))
17130 || type_dependent_expression_p (TREE_OPERAND (t, 1)))
17139 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
17140 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if
17141 no such TYPE can be found. Note that this function peers inside
17142 uninstantiated templates and therefore should be used only in
17143 extremely limited situations. ONLY_CURRENT_P restricts this
17144 peering to the currently open classes hierarchy (which is required
17145 when comparing types). */
17148 resolve_typename_type (tree type, bool only_current_p)
17157 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
17159 scope = TYPE_CONTEXT (type);
17160 /* Usually the non-qualified identifier of a TYPENAME_TYPE is
17161 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of
17162 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing
17163 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified
17164 identifier of the TYPENAME_TYPE anymore.
17165 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the
17166 TYPENAME_TYPE instead, we avoid messing up with a possible
17167 typedef variant case. */
17168 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type));
17170 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
17171 it first before we can figure out what NAME refers to. */
17172 if (TREE_CODE (scope) == TYPENAME_TYPE)
17173 scope = resolve_typename_type (scope, only_current_p);
17174 /* If we don't know what SCOPE refers to, then we cannot resolve the
17176 if (TREE_CODE (scope) == TYPENAME_TYPE)
17178 /* If the SCOPE is a template type parameter, we have no way of
17179 resolving the name. */
17180 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
17182 /* If the SCOPE is not the current instantiation, there's no reason
17183 to look inside it. */
17184 if (only_current_p && !currently_open_class (scope))
17186 /* If SCOPE isn't the template itself, it will not have a valid
17187 TYPE_FIELDS list. */
17188 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope)))
17189 /* scope is either the template itself or a compatible instantiation
17190 like X<T>, so look up the name in the original template. */
17191 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
17193 /* scope is a partial instantiation, so we can't do the lookup or we
17194 will lose the template arguments. */
17196 /* Enter the SCOPE so that name lookup will be resolved as if we
17197 were in the class definition. In particular, SCOPE will no
17198 longer be considered a dependent type. */
17199 pushed_scope = push_scope (scope);
17200 /* Look up the declaration. */
17201 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
17203 result = NULL_TREE;
17205 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
17206 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
17209 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
17210 && TREE_CODE (decl) == TYPE_DECL)
17212 result = TREE_TYPE (decl);
17213 if (result == error_mark_node)
17214 result = NULL_TREE;
17216 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
17217 && DECL_CLASS_TEMPLATE_P (decl))
17221 /* Obtain the template and the arguments. */
17222 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
17223 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
17224 /* Instantiate the template. */
17225 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
17226 /*entering_scope=*/0,
17227 tf_error | tf_user);
17228 if (result == error_mark_node)
17229 result = NULL_TREE;
17232 /* Leave the SCOPE. */
17234 pop_scope (pushed_scope);
17236 /* If we failed to resolve it, return the original typename. */
17240 /* If lookup found a typename type, resolve that too. */
17241 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result))
17243 /* Ill-formed programs can cause infinite recursion here, so we
17244 must catch that. */
17245 TYPENAME_IS_RESOLVING_P (type) = 1;
17246 result = resolve_typename_type (result, only_current_p);
17247 TYPENAME_IS_RESOLVING_P (type) = 0;
17250 /* Qualify the resulting type. */
17251 quals = cp_type_quals (type);
17253 result = cp_build_qualified_type (result, cp_type_quals (result) | quals);
17258 /* EXPR is an expression which is not type-dependent. Return a proxy
17259 for EXPR that can be used to compute the types of larger
17260 expressions containing EXPR. */
17263 build_non_dependent_expr (tree expr)
17267 /* Preserve null pointer constants so that the type of things like
17268 "p == 0" where "p" is a pointer can be determined. */
17269 if (null_ptr_cst_p (expr))
17271 /* Preserve OVERLOADs; the functions must be available to resolve
17274 if (TREE_CODE (inner_expr) == STMT_EXPR)
17275 inner_expr = stmt_expr_value_expr (inner_expr);
17276 if (TREE_CODE (inner_expr) == ADDR_EXPR)
17277 inner_expr = TREE_OPERAND (inner_expr, 0);
17278 if (TREE_CODE (inner_expr) == COMPONENT_REF)
17279 inner_expr = TREE_OPERAND (inner_expr, 1);
17280 if (is_overloaded_fn (inner_expr)
17281 || TREE_CODE (inner_expr) == OFFSET_REF)
17283 /* There is no need to return a proxy for a variable. */
17284 if (TREE_CODE (expr) == VAR_DECL)
17286 /* Preserve string constants; conversions from string constants to
17287 "char *" are allowed, even though normally a "const char *"
17288 cannot be used to initialize a "char *". */
17289 if (TREE_CODE (expr) == STRING_CST)
17291 /* Preserve arithmetic constants, as an optimization -- there is no
17292 reason to create a new node. */
17293 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
17295 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
17296 There is at least one place where we want to know that a
17297 particular expression is a throw-expression: when checking a ?:
17298 expression, there are special rules if the second or third
17299 argument is a throw-expression. */
17300 if (TREE_CODE (expr) == THROW_EXPR)
17303 if (TREE_CODE (expr) == COND_EXPR)
17304 return build3 (COND_EXPR,
17306 TREE_OPERAND (expr, 0),
17307 (TREE_OPERAND (expr, 1)
17308 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
17309 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
17310 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
17311 if (TREE_CODE (expr) == COMPOUND_EXPR
17312 && !COMPOUND_EXPR_OVERLOADED (expr))
17313 return build2 (COMPOUND_EXPR,
17315 TREE_OPERAND (expr, 0),
17316 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
17318 /* If the type is unknown, it can't really be non-dependent */
17319 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
17321 /* Otherwise, build a NON_DEPENDENT_EXPR.
17323 REFERENCE_TYPEs are not stripped for expressions in templates
17324 because doing so would play havoc with mangling. Consider, for
17327 template <typename T> void f<T& g>() { g(); }
17329 In the body of "f", the expression for "g" will have
17330 REFERENCE_TYPE, even though the standard says that it should
17331 not. The reason is that we must preserve the syntactic form of
17332 the expression so that mangling (say) "f<g>" inside the body of
17333 "f" works out correctly. Therefore, the REFERENCE_TYPE is
17335 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
17338 /* ARGS is a vector of expressions as arguments to a function call.
17339 Replace the arguments with equivalent non-dependent expressions.
17340 This modifies ARGS in place. */
17343 make_args_non_dependent (VEC(tree,gc) *args)
17348 for (ix = 0; VEC_iterate (tree, args, ix, arg); ++ix)
17350 tree newarg = build_non_dependent_expr (arg);
17352 VEC_replace (tree, args, ix, newarg);
17356 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM
17357 with a level one deeper than the actual template parms. */
17364 /* ??? Is it worth caching this for multiple autos at the same level? */
17365 au = cxx_make_type (TEMPLATE_TYPE_PARM);
17366 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION,
17367 TYPE_DECL, get_identifier ("auto"), au);
17368 TYPE_STUB_DECL (au) = TYPE_NAME (au);
17369 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index
17370 (0, processing_template_decl + 1, processing_template_decl + 1,
17371 TYPE_NAME (au), NULL_TREE);
17372 TYPE_CANONICAL (au) = canonical_type_parameter (au);
17373 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1;
17374 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au));
17379 /* Replace auto in TYPE with std::initializer_list<auto>. */
17382 listify_autos (tree type, tree auto_node)
17384 tree std_init_list = namespace_binding
17385 (get_identifier ("initializer_list"), std_node);
17388 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list))
17390 error ("deducing auto from brace-enclosed initializer list requires "
17391 "#include <initializer_list>");
17392 return error_mark_node;
17394 argvec = make_tree_vec (1);
17395 TREE_VEC_ELT (argvec, 0) = auto_node;
17396 init_auto = lookup_template_class (std_init_list, argvec, NULL_TREE,
17397 NULL_TREE, 0, tf_warning_or_error);
17399 TREE_VEC_ELT (argvec, 0) = init_auto;
17400 if (processing_template_decl)
17401 argvec = add_to_template_args (current_template_args (), argvec);
17402 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
17405 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced
17406 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */
17409 do_auto_deduction (tree type, tree init, tree auto_node)
17411 tree parms, tparms, targs;
17415 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto
17416 with either a new invented type template parameter U or, if the
17417 initializer is a braced-init-list (8.5.4), with
17418 std::initializer_list<U>. */
17419 if (BRACE_ENCLOSED_INITIALIZER_P (init))
17420 type = listify_autos (type, auto_node);
17422 parms = build_tree_list (NULL_TREE, type);
17424 tparms = make_tree_vec (1);
17425 targs = make_tree_vec (1);
17426 TREE_VEC_ELT (tparms, 0)
17427 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node));
17428 val = type_unification_real (tparms, targs, parms, args, 1, 0,
17429 DEDUCE_CALL, LOOKUP_NORMAL);
17432 error ("unable to deduce %qT from %qE", type, init);
17433 return error_mark_node;
17436 if (processing_template_decl)
17437 targs = add_to_template_args (current_template_args (), targs);
17438 return tsubst (type, targs, tf_warning_or_error, NULL_TREE);
17441 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the
17445 splice_late_return_type (tree type, tree late_return_type)
17449 if (late_return_type == NULL_TREE)
17451 argvec = make_tree_vec (1);
17452 TREE_VEC_ELT (argvec, 0) = late_return_type;
17453 if (processing_template_decl)
17454 argvec = add_to_template_args (current_template_args (), argvec);
17455 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE);
17458 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */
17461 is_auto (const_tree type)
17463 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
17464 && TYPE_IDENTIFIER (type) == get_identifier ("auto"))
17470 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only
17471 appear as a type-specifier for the declaration in question, we don't
17472 have to look through the whole type. */
17475 type_uses_auto (tree type)
17477 enum tree_code code;
17478 if (is_auto (type))
17481 code = TREE_CODE (type);
17483 if (code == POINTER_TYPE || code == REFERENCE_TYPE
17484 || code == OFFSET_TYPE || code == FUNCTION_TYPE
17485 || code == METHOD_TYPE || code == ARRAY_TYPE)
17486 return type_uses_auto (TREE_TYPE (type));
17488 if (TYPE_PTRMEMFUNC_P (type))
17489 return type_uses_auto (TREE_TYPE (TREE_TYPE
17490 (TYPE_PTRMEMFUNC_FN_TYPE (type))));
17495 /* For a given template T, return the list of typedefs referenced
17496 in T for which access check is needed at T instantiation time.
17497 T is either a FUNCTION_DECL or a RECORD_TYPE.
17498 Those typedefs were added to T by the function
17499 append_type_to_template_for_access_check. */
17502 get_types_needing_access_check (tree t)
17504 tree ti, result = NULL_TREE;
17506 if (!t || t == error_mark_node)
17509 if (!(ti = get_template_info (t)))
17512 if (TREE_CODE (t) == RECORD_TYPE || TREE_CODE (t) == FUNCTION_DECL)
17514 if (!TI_TEMPLATE (ti))
17517 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti);
17523 /* Append the typedef TYPE_DECL used in template T to a list of typedefs
17524 tied to T. That list of typedefs will be access checked at
17525 T instantiation time.
17526 T is either a FUNCTION_DECL or a RECORD_TYPE.
17527 TYPE_DECL is a TYPE_DECL node representing a typedef.
17528 SCOPE is the scope through which TYPE_DECL is accessed.
17530 This function is a subroutine of
17531 append_type_to_template_for_access_check. */
17534 append_type_to_template_for_access_check_1 (tree t,
17540 if (!t || t == error_mark_node)
17543 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL
17544 || TREE_CODE (t) == RECORD_TYPE)
17546 && TREE_CODE (type_decl) == TYPE_DECL
17549 if (!(ti = get_template_info (t)))
17552 gcc_assert (TI_TEMPLATE (ti));
17554 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti) =
17555 tree_cons (type_decl, scope, TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti));
17558 /* Append TYPE_DECL to the template TEMPL.
17559 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL.
17560 At TEMPL instanciation time, TYPE_DECL will be checked to see
17561 if it can be accessed through SCOPE.
17563 e.g. consider the following code snippet:
17570 template<class U> struct S
17577 At S<char> instantiation time, we need to check the access of C::myint
17578 In other words, we need to check the access of the myint typedef through
17579 the C scope. For that purpose, this function will add the myint typedef
17580 and the scope C through which its being accessed to a list of typedefs
17581 tied to the template S. That list will be walked at template instantiation
17582 time and access check performed on each typedefs it contains.
17583 Note that this particular code snippet should yield an error because
17584 myint is private to C. */
17587 append_type_to_template_for_access_check (tree templ,
17593 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL));
17595 /* Make sure we don't append the type to the template twice. */
17596 for (node = get_types_needing_access_check (templ);
17598 node = TREE_CHAIN (node))
17600 tree decl = TREE_PURPOSE (node);
17601 tree type_scope = TREE_VALUE (node);
17603 if (decl == type_decl && type_scope == scope)
17607 append_type_to_template_for_access_check_1 (templ, type_decl, scope);
17610 /* Set up the hash tables for template instantiations. */
17613 init_template_processing (void)
17615 decl_specializations = htab_create_ggc (37,
17616 hash_specialization,
17617 eq_specializations,
17619 type_specializations = htab_create_ggc (37,
17620 hash_specialization,
17621 eq_specializations,
17625 #include "gt-cp-pt.h"