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 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, USA. */
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"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work.
56 The TREE_PURPOSE of each entry is either a DECL (for a function or
57 static data member), or a TYPE (for a class) indicating what we are
58 hoping to instantiate. The TREE_VALUE is not used. */
59 static GTY(()) tree pending_templates;
60 static GTY(()) tree last_pending_template;
62 int processing_template_parmlist;
63 static int template_header_count;
65 static GTY(()) tree saved_trees;
66 static GTY(()) varray_type inline_parm_levels;
67 static size_t inline_parm_levels_used;
69 static GTY(()) tree current_tinst_level;
71 static GTY(()) tree saved_access_scope;
73 /* Live only within one (recursive) call to tsubst_expr. We use
74 this to pass the statement expression node from the STMT_EXPR
75 to the EXPR_STMT that is its result. */
76 static tree cur_stmt_expr;
78 /* A map from local variable declarations in the body of the template
79 presently being instantiated to the corresponding instantiated
81 static htab_t local_specializations;
83 #define UNIFY_ALLOW_NONE 0
84 #define UNIFY_ALLOW_MORE_CV_QUAL 1
85 #define UNIFY_ALLOW_LESS_CV_QUAL 2
86 #define UNIFY_ALLOW_DERIVED 4
87 #define UNIFY_ALLOW_INTEGER 8
88 #define UNIFY_ALLOW_OUTER_LEVEL 16
89 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
90 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
92 static void push_access_scope (tree);
93 static void pop_access_scope (tree);
94 static int resolve_overloaded_unification (tree, tree, tree, tree,
95 unification_kind_t, int);
96 static int try_one_overload (tree, tree, tree, tree, tree,
97 unification_kind_t, int, bool);
98 static int unify (tree, tree, tree, tree, int);
99 static void add_pending_template (tree);
100 static void reopen_tinst_level (tree);
101 static tree classtype_mangled_name (tree);
102 static char* mangle_class_name_for_template (const char *, tree, tree);
103 static tree tsubst_initializer_list (tree, tree);
104 static tree get_class_bindings (tree, tree, tree);
105 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
106 static void tsubst_enum (tree, tree, tree);
107 static tree add_to_template_args (tree, tree);
108 static tree add_outermost_template_args (tree, tree);
109 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
110 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
111 static int type_unification_real (tree, tree, tree, tree,
112 int, unification_kind_t, int);
113 static void note_template_header (int);
114 static tree convert_nontype_argument_function (tree, tree);
115 static tree convert_nontype_argument (tree, tree);
116 static tree convert_template_argument (tree, tree, tree,
117 tsubst_flags_t, int, tree);
118 static int for_each_template_parm (tree, tree_fn_t, void*,
119 struct pointer_set_t*);
120 static tree build_template_parm_index (int, int, int, tree, tree);
121 static int inline_needs_template_parms (tree);
122 static void push_inline_template_parms_recursive (tree, int);
123 static tree retrieve_local_specialization (tree);
124 static void register_local_specialization (tree, tree);
125 static tree reduce_template_parm_level (tree, tree, int);
126 static int mark_template_parm (tree, void *);
127 static int template_parm_this_level_p (tree, void *);
128 static tree tsubst_friend_function (tree, tree);
129 static tree tsubst_friend_class (tree, tree);
130 static int can_complete_type_without_circularity (tree);
131 static tree get_bindings (tree, tree, tree, bool);
132 static int template_decl_level (tree);
133 static int check_cv_quals_for_unify (int, tree, tree);
134 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
135 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
136 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
137 static void regenerate_decl_from_template (tree, tree);
138 static tree most_specialized (tree, tree, tree);
139 static tree most_specialized_class (tree, tree);
140 static int template_class_depth_real (tree, int);
141 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
142 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
143 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
144 static void check_specialization_scope (void);
145 static tree process_partial_specialization (tree);
146 static void set_current_access_from_decl (tree);
147 static void check_default_tmpl_args (tree, tree, int, int);
148 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
149 static tree get_template_base (tree, tree, tree, tree);
150 static int verify_class_unification (tree, tree, tree);
151 static tree try_class_unification (tree, tree, tree, tree);
152 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
154 static tree determine_specialization (tree, tree, tree *, int, int);
155 static int template_args_equal (tree, tree);
156 static void tsubst_default_arguments (tree);
157 static tree for_each_template_parm_r (tree *, int *, void *);
158 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
159 static void copy_default_args_to_explicit_spec (tree);
160 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
161 static int eq_local_specializations (const void *, const void *);
162 static bool dependent_type_p_r (tree);
163 static tree tsubst (tree, tree, tsubst_flags_t, tree);
164 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
165 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
167 /* Make the current scope suitable for access checking when we are
168 processing T. T can be FUNCTION_DECL for instantiated function
169 template, or VAR_DECL for static member variable (need by
170 instantiate_decl). */
173 push_access_scope (tree t)
175 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
176 || TREE_CODE (t) == VAR_DECL);
178 if (DECL_FRIEND_CONTEXT (t))
179 push_nested_class (DECL_FRIEND_CONTEXT (t));
180 else if (DECL_CLASS_SCOPE_P (t))
181 push_nested_class (DECL_CONTEXT (t));
183 push_to_top_level ();
185 if (TREE_CODE (t) == FUNCTION_DECL)
187 saved_access_scope = tree_cons
188 (NULL_TREE, current_function_decl, saved_access_scope);
189 current_function_decl = t;
193 /* Restore the scope set up by push_access_scope. T is the node we
197 pop_access_scope (tree t)
199 if (TREE_CODE (t) == FUNCTION_DECL)
201 current_function_decl = TREE_VALUE (saved_access_scope);
202 saved_access_scope = TREE_CHAIN (saved_access_scope);
205 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
208 pop_from_top_level ();
211 /* Do any processing required when DECL (a member template
212 declaration) is finished. Returns the TEMPLATE_DECL corresponding
213 to DECL, unless it is a specialization, in which case the DECL
214 itself is returned. */
217 finish_member_template_decl (tree decl)
219 if (decl == error_mark_node)
220 return error_mark_node;
222 gcc_assert (DECL_P (decl));
224 if (TREE_CODE (decl) == TYPE_DECL)
228 type = TREE_TYPE (decl);
229 if (IS_AGGR_TYPE (type)
230 && CLASSTYPE_TEMPLATE_INFO (type)
231 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
233 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
234 check_member_template (tmpl);
239 else if (TREE_CODE (decl) == FIELD_DECL)
240 error ("data member %qD cannot be a member template", decl);
241 else if (DECL_TEMPLATE_INFO (decl))
243 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
245 check_member_template (DECL_TI_TEMPLATE (decl));
246 return DECL_TI_TEMPLATE (decl);
252 error ("invalid member template declaration %qD", decl);
254 return error_mark_node;
257 /* Returns the template nesting level of the indicated class TYPE.
267 A<T>::B<U> has depth two, while A<T> has depth one.
268 Both A<T>::B<int> and A<int>::B<U> have depth one, if
269 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
272 This function is guaranteed to return 0 if passed NULL_TREE so
273 that, for example, `template_class_depth (current_class_type)' is
277 template_class_depth_real (tree type, int count_specializations)
282 type && TREE_CODE (type) != NAMESPACE_DECL;
283 type = (TREE_CODE (type) == FUNCTION_DECL)
284 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
286 if (TREE_CODE (type) != FUNCTION_DECL)
288 if (CLASSTYPE_TEMPLATE_INFO (type)
289 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
290 && ((count_specializations
291 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
292 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
297 if (DECL_TEMPLATE_INFO (type)
298 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
299 && ((count_specializations
300 && DECL_TEMPLATE_SPECIALIZATION (type))
301 || uses_template_parms (DECL_TI_ARGS (type))))
309 /* Returns the template nesting level of the indicated class TYPE.
310 Like template_class_depth_real, but instantiations do not count in
314 template_class_depth (tree type)
316 return template_class_depth_real (type, /*count_specializations=*/0);
319 /* Returns 1 if processing DECL as part of do_pending_inlines
320 needs us to push template parms. */
323 inline_needs_template_parms (tree decl)
325 if (! DECL_TEMPLATE_INFO (decl))
328 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
329 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
332 /* Subroutine of maybe_begin_member_template_processing.
333 Push the template parms in PARMS, starting from LEVELS steps into the
334 chain, and ending at the beginning, since template parms are listed
338 push_inline_template_parms_recursive (tree parmlist, int levels)
340 tree parms = TREE_VALUE (parmlist);
344 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
346 ++processing_template_decl;
347 current_template_parms
348 = tree_cons (size_int (processing_template_decl),
349 parms, current_template_parms);
350 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
352 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
354 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
356 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
357 gcc_assert (DECL_P (parm));
359 switch (TREE_CODE (parm))
368 /* Make a CONST_DECL as is done in process_template_parm.
369 It is ugly that we recreate this here; the original
370 version built in process_template_parm is no longer
372 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
374 DECL_ARTIFICIAL (decl) = 1;
375 TREE_CONSTANT (decl) = 1;
376 TREE_INVARIANT (decl) = 1;
377 TREE_READONLY (decl) = 1;
378 DECL_INITIAL (decl) = DECL_INITIAL (parm);
379 SET_DECL_TEMPLATE_PARM_P (decl);
390 /* Restore the template parameter context for a member template or
391 a friend template defined in a class definition. */
394 maybe_begin_member_template_processing (tree decl)
399 if (inline_needs_template_parms (decl))
401 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
402 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
404 if (DECL_TEMPLATE_SPECIALIZATION (decl))
407 parms = TREE_CHAIN (parms);
410 push_inline_template_parms_recursive (parms, levels);
413 /* Remember how many levels of template parameters we pushed so that
414 we can pop them later. */
415 if (!inline_parm_levels)
416 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
417 if (inline_parm_levels_used == inline_parm_levels->num_elements)
418 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
419 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
420 ++inline_parm_levels_used;
423 /* Undo the effects of maybe_begin_member_template_processing. */
426 maybe_end_member_template_processing (void)
430 if (!inline_parm_levels_used)
433 --inline_parm_levels_used;
435 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
438 --processing_template_decl;
439 current_template_parms = TREE_CHAIN (current_template_parms);
444 /* Return a new template argument vector which contains all of ARGS,
445 but has as its innermost set of arguments the EXTRA_ARGS. */
448 add_to_template_args (tree args, tree extra_args)
455 extra_depth = TMPL_ARGS_DEPTH (extra_args);
456 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
458 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
459 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
461 for (j = 1; j <= extra_depth; ++j, ++i)
462 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
467 /* Like add_to_template_args, but only the outermost ARGS are added to
468 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
469 (EXTRA_ARGS) levels are added. This function is used to combine
470 the template arguments from a partial instantiation with the
471 template arguments used to attain the full instantiation from the
472 partial instantiation. */
475 add_outermost_template_args (tree args, tree extra_args)
479 /* If there are more levels of EXTRA_ARGS than there are ARGS,
480 something very fishy is going on. */
481 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
483 /* If *all* the new arguments will be the EXTRA_ARGS, just return
485 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
488 /* For the moment, we make ARGS look like it contains fewer levels. */
489 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
491 new_args = add_to_template_args (args, extra_args);
493 /* Now, we restore ARGS to its full dimensions. */
494 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
499 /* Return the N levels of innermost template arguments from the ARGS. */
502 get_innermost_template_args (tree args, int n)
510 /* If N is 1, just return the innermost set of template arguments. */
512 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
514 /* If we're not removing anything, just return the arguments we were
516 extra_levels = TMPL_ARGS_DEPTH (args) - n;
517 gcc_assert (extra_levels >= 0);
518 if (extra_levels == 0)
521 /* Make a new set of arguments, not containing the outer arguments. */
522 new_args = make_tree_vec (n);
523 for (i = 1; i <= n; ++i)
524 SET_TMPL_ARGS_LEVEL (new_args, i,
525 TMPL_ARGS_LEVEL (args, i + extra_levels));
530 /* We've got a template header coming up; push to a new level for storing
534 begin_template_parm_list (void)
536 /* We use a non-tag-transparent scope here, which causes pushtag to
537 put tags in this scope, rather than in the enclosing class or
538 namespace scope. This is the right thing, since we want
539 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
540 global template class, push_template_decl handles putting the
541 TEMPLATE_DECL into top-level scope. For a nested template class,
544 template <class T> struct S1 {
545 template <class T> struct S2 {};
548 pushtag contains special code to call pushdecl_with_scope on the
549 TEMPLATE_DECL for S2. */
550 begin_scope (sk_template_parms, NULL);
551 ++processing_template_decl;
552 ++processing_template_parmlist;
553 note_template_header (0);
556 /* This routine is called when a specialization is declared. If it is
557 invalid to declare a specialization here, an error is reported. */
560 check_specialization_scope (void)
562 tree scope = current_scope ();
566 An explicit specialization shall be declared in the namespace of
567 which the template is a member, or, for member templates, in the
568 namespace of which the enclosing class or enclosing class
569 template is a member. An explicit specialization of a member
570 function, member class or static data member of a class template
571 shall be declared in the namespace of which the class template
573 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
574 error ("explicit specialization in non-namespace scope %qD", scope);
578 In an explicit specialization declaration for a member of a class
579 template or a member template that appears in namespace scope,
580 the member template and some of its enclosing class templates may
581 remain unspecialized, except that the declaration shall not
582 explicitly specialize a class member template if its enclosing
583 class templates are not explicitly specialized as well. */
584 if (current_template_parms)
585 error ("enclosing class templates are not explicitly specialized");
588 /* We've just seen template <>. */
591 begin_specialization (void)
593 begin_scope (sk_template_spec, NULL);
594 note_template_header (1);
595 check_specialization_scope ();
598 /* Called at then end of processing a declaration preceded by
602 end_specialization (void)
605 reset_specialization ();
608 /* Any template <>'s that we have seen thus far are not referring to a
609 function specialization. */
612 reset_specialization (void)
614 processing_specialization = 0;
615 template_header_count = 0;
618 /* We've just seen a template header. If SPECIALIZATION is nonzero,
619 it was of the form template <>. */
622 note_template_header (int specialization)
624 processing_specialization = specialization;
625 template_header_count++;
628 /* We're beginning an explicit instantiation. */
631 begin_explicit_instantiation (void)
633 gcc_assert (!processing_explicit_instantiation);
634 processing_explicit_instantiation = true;
639 end_explicit_instantiation (void)
641 gcc_assert (processing_explicit_instantiation);
642 processing_explicit_instantiation = false;
645 /* An explicit specialization or partial specialization TMPL is being
646 declared. Check that the namespace in which the specialization is
647 occurring is permissible. Returns false iff it is invalid to
648 specialize TMPL in the current namespace. */
651 check_specialization_namespace (tree tmpl)
653 tree tpl_ns = decl_namespace_context (tmpl);
657 An explicit specialization shall be declared in the namespace of
658 which the template is a member, or, for member templates, in the
659 namespace of which the enclosing class or enclosing class
660 template is a member. An explicit specialization of a member
661 function, member class or static data member of a class template
662 shall be declared in the namespace of which the class template is
664 if (is_associated_namespace (current_namespace, tpl_ns))
665 /* Same or super-using namespace. */
669 pedwarn ("specialization of %qD in different namespace", tmpl);
670 pedwarn (" from definition of %q+#D", tmpl);
675 /* SPEC is an explicit instantiation. Check that it is valid to
676 perform this explicit instantiation in the current namespace. */
679 check_explicit_instantiation_namespace (tree spec)
683 /* DR 275: An explicit instantiation shall appear in an enclosing
684 namespace of its template. */
685 ns = decl_namespace_context (spec);
686 if (!is_ancestor (current_namespace, ns))
687 pedwarn ("explicit instantiation of %qD in namespace %qD "
688 "(which does not enclose namespace %qD)",
689 spec, current_namespace, ns);
692 /* The TYPE is being declared. If it is a template type, that means it
693 is a partial specialization. Do appropriate error-checking. */
696 maybe_process_partial_specialization (tree type)
698 /* TYPE maybe an ERROR_MARK_NODE. */
699 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
701 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
703 /* This is for ordinary explicit specialization and partial
704 specialization of a template class such as:
706 template <> class C<int>;
710 template <class T> class C<T*>;
712 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
714 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
715 && !COMPLETE_TYPE_P (type))
717 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
718 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
719 if (processing_template_decl)
720 push_template_decl (TYPE_MAIN_DECL (type));
722 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
723 error ("specialization of %qT after instantiation", type);
725 else if (CLASS_TYPE_P (type)
726 && !CLASSTYPE_USE_TEMPLATE (type)
727 && CLASSTYPE_TEMPLATE_INFO (type)
728 && context && CLASS_TYPE_P (context)
729 && CLASSTYPE_TEMPLATE_INFO (context))
731 /* This is for an explicit specialization of member class
732 template according to [temp.expl.spec/18]:
734 template <> template <class U> class C<int>::D;
736 The context `C<int>' must be an implicit instantiation.
737 Otherwise this is just a member class template declared
740 template <> class C<int> { template <class U> class D; };
741 template <> template <class U> class C<int>::D;
743 In the first case, `C<int>::D' is a specialization of `C<T>::D'
744 while in the second case, `C<int>::D' is a primary template
745 and `C<T>::D' may not exist. */
747 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
748 && !COMPLETE_TYPE_P (type))
752 if (current_namespace
753 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
755 pedwarn ("specializing %q#T in different namespace", type);
756 pedwarn (" from definition of %q+#D",
757 CLASSTYPE_TI_TEMPLATE (type));
760 /* Check for invalid specialization after instantiation:
762 template <> template <> class C<int>::D<int>;
763 template <> template <class U> class C<int>::D; */
765 for (t = DECL_TEMPLATE_INSTANTIATIONS
766 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
767 t; t = TREE_CHAIN (t))
768 if (TREE_VALUE (t) != type
769 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
770 error ("specialization %qT after instantiation %qT",
771 type, TREE_VALUE (t));
773 /* Mark TYPE as a specialization. And as a result, we only
774 have one level of template argument for the innermost
776 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
777 CLASSTYPE_TI_ARGS (type)
778 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
781 else if (processing_specialization)
782 error ("explicit specialization of non-template %qT", type);
785 /* Returns nonzero if we can optimize the retrieval of specializations
786 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
787 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
790 optimize_specialization_lookup_p (tree tmpl)
792 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
793 && DECL_CLASS_SCOPE_P (tmpl)
794 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
796 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
797 /* The optimized lookup depends on the fact that the
798 template arguments for the member function template apply
799 purely to the containing class, which is not true if the
800 containing class is an explicit or partial
802 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
803 && !DECL_MEMBER_TEMPLATE_P (tmpl)
804 && !DECL_CONV_FN_P (tmpl)
805 /* It is possible to have a template that is not a member
806 template and is not a member of a template class:
808 template <typename T>
809 struct S { friend A::f(); };
811 Here, the friend function is a template, but the context does
812 not have template information. The optimized lookup relies
813 on having ARGS be the template arguments for both the class
814 and the function template. */
815 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
818 /* Retrieve the specialization (in the sense of [temp.spec] - a
819 specialization is either an instantiation or an explicit
820 specialization) of TMPL for the given template ARGS. If there is
821 no such specialization, return NULL_TREE. The ARGS are a vector of
822 arguments, or a vector of vectors of arguments, in the case of
823 templates with more than one level of parameters.
825 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
826 then we search for a partial specialization matching ARGS. This
827 parameter is ignored if TMPL is not a class template. */
830 retrieve_specialization (tree tmpl, tree args,
831 bool class_specializations_p)
833 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
835 /* There should be as many levels of arguments as there are
836 levels of parameters. */
837 gcc_assert (TMPL_ARGS_DEPTH (args)
838 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
840 if (optimize_specialization_lookup_p (tmpl))
843 tree class_specialization;
844 VEC(tree,gc) *methods;
848 /* The template arguments actually apply to the containing
849 class. Find the class specialization with those
851 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
853 = retrieve_specialization (class_template, args,
854 /*class_specializations_p=*/false);
855 if (!class_specialization)
857 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
858 for the specialization. */
859 idx = class_method_index_for_fn (class_specialization, tmpl);
862 /* Iterate through the methods with the indicated name, looking
863 for the one that has an instance of TMPL. */
864 methods = CLASSTYPE_METHOD_VEC (class_specialization);
865 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
867 tree fn = OVL_CURRENT (fns);
868 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
878 /* Class templates store their instantiations on the
879 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
880 DECL_TEMPLATE_SPECIALIZATIONS list. */
881 if (!class_specializations_p
882 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
883 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
885 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
887 /* Iterate through the list until we find a matching template. */
888 while (*sp != NULL_TREE)
892 if (comp_template_args (TREE_PURPOSE (spec), args))
894 /* Use the move-to-front heuristic to speed up future
898 *sp = TREE_CHAIN (*sp);
899 TREE_CHAIN (spec) = *head;
902 return TREE_VALUE (spec);
904 sp = &TREE_CHAIN (spec);
911 /* Like retrieve_specialization, but for local declarations. */
914 retrieve_local_specialization (tree tmpl)
916 tree spec = htab_find_with_hash (local_specializations, tmpl,
917 htab_hash_pointer (tmpl));
918 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
921 /* Returns nonzero iff DECL is a specialization of TMPL. */
924 is_specialization_of (tree decl, tree tmpl)
928 if (TREE_CODE (decl) == FUNCTION_DECL)
932 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
938 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
940 for (t = TREE_TYPE (decl);
942 t = CLASSTYPE_USE_TEMPLATE (t)
943 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
944 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
951 /* Returns nonzero iff DECL is a specialization of friend declaration
952 FRIEND according to [temp.friend]. */
955 is_specialization_of_friend (tree decl, tree friend)
957 bool need_template = true;
960 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
961 || TREE_CODE (decl) == TYPE_DECL);
963 /* For [temp.friend/6] when FRIEND is an ordinary member function
964 of a template class, we want to check if DECL is a specialization
966 if (TREE_CODE (friend) == FUNCTION_DECL
967 && DECL_TEMPLATE_INFO (friend)
968 && !DECL_USE_TEMPLATE (friend))
970 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
971 friend = DECL_TI_TEMPLATE (friend);
972 need_template = false;
974 else if (TREE_CODE (friend) == TEMPLATE_DECL
975 && !PRIMARY_TEMPLATE_P (friend))
976 need_template = false;
978 /* There is nothing to do if this is not a template friend. */
979 if (TREE_CODE (friend) != TEMPLATE_DECL)
982 if (is_specialization_of (decl, friend))
986 A member of a class template may be declared to be a friend of a
987 non-template class. In this case, the corresponding member of
988 every specialization of the class template is a friend of the
989 class granting friendship.
991 For example, given a template friend declaration
993 template <class T> friend void A<T>::f();
995 the member function below is considered a friend
997 template <> struct A<int> {
1001 For this type of template friend, TEMPLATE_DEPTH below will be
1002 nonzero. To determine if DECL is a friend of FRIEND, we first
1003 check if the enclosing class is a specialization of another. */
1005 template_depth = template_class_depth (DECL_CONTEXT (friend));
1007 && DECL_CLASS_SCOPE_P (decl)
1008 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1009 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
1011 /* Next, we check the members themselves. In order to handle
1012 a few tricky cases, such as when FRIEND's are
1014 template <class T> friend void A<T>::g(T t);
1015 template <class T> template <T t> friend void A<T>::h();
1019 void A<int>::g(int);
1020 template <int> void A<int>::h();
1022 we need to figure out ARGS, the template arguments from
1023 the context of DECL. This is required for template substitution
1024 of `T' in the function parameter of `g' and template parameter
1025 of `h' in the above examples. Here ARGS corresponds to `int'. */
1027 tree context = DECL_CONTEXT (decl);
1028 tree args = NULL_TREE;
1029 int current_depth = 0;
1031 while (current_depth < template_depth)
1033 if (CLASSTYPE_TEMPLATE_INFO (context))
1035 if (current_depth == 0)
1036 args = TYPE_TI_ARGS (context);
1038 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1041 context = TYPE_CONTEXT (context);
1044 if (TREE_CODE (decl) == FUNCTION_DECL)
1049 tree friend_args_type;
1050 tree decl_args_type;
1052 /* Make sure that both DECL and FRIEND are templates or
1054 is_template = DECL_TEMPLATE_INFO (decl)
1055 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1056 if (need_template ^ is_template)
1058 else if (is_template)
1060 /* If both are templates, check template parameter list. */
1062 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1064 if (!comp_template_parms
1065 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1069 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1072 decl_type = TREE_TYPE (decl);
1074 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1075 tf_none, NULL_TREE);
1076 if (friend_type == error_mark_node)
1079 /* Check if return types match. */
1080 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1083 /* Check if function parameter types match, ignoring the
1084 `this' parameter. */
1085 friend_args_type = TYPE_ARG_TYPES (friend_type);
1086 decl_args_type = TYPE_ARG_TYPES (decl_type);
1087 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1088 friend_args_type = TREE_CHAIN (friend_args_type);
1089 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1090 decl_args_type = TREE_CHAIN (decl_args_type);
1092 return compparms (decl_args_type, friend_args_type);
1096 /* DECL is a TYPE_DECL */
1098 tree decl_type = TREE_TYPE (decl);
1100 /* Make sure that both DECL and FRIEND are templates or
1103 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1104 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1106 if (need_template ^ is_template)
1108 else if (is_template)
1111 /* If both are templates, check the name of the two
1112 TEMPLATE_DECL's first because is_friend didn't. */
1113 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1114 != DECL_NAME (friend))
1117 /* Now check template parameter list. */
1119 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1121 return comp_template_parms
1122 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1126 return (DECL_NAME (decl)
1127 == DECL_NAME (friend));
1133 /* Register the specialization SPEC as a specialization of TMPL with
1134 the indicated ARGS. IS_FRIEND indicates whether the specialization
1135 is actually just a friend declaration. Returns SPEC, or an
1136 equivalent prior declaration, if available. */
1139 register_specialization (tree spec, tree tmpl, tree args, bool is_friend)
1143 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1145 if (TREE_CODE (spec) == FUNCTION_DECL
1146 && uses_template_parms (DECL_TI_ARGS (spec)))
1147 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1148 register it; we want the corresponding TEMPLATE_DECL instead.
1149 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1150 the more obvious `uses_template_parms (spec)' to avoid problems
1151 with default function arguments. In particular, given
1152 something like this:
1154 template <class T> void f(T t1, T t = T())
1156 the default argument expression is not substituted for in an
1157 instantiation unless and until it is actually needed. */
1160 fn = retrieve_specialization (tmpl, args,
1161 /*class_specializations_p=*/false);
1162 /* We can sometimes try to re-register a specialization that we've
1163 already got. In particular, regenerate_decl_from_template calls
1164 duplicate_decls which will update the specialization list. But,
1165 we'll still get called again here anyhow. It's more convenient
1166 to simply allow this than to try to prevent it. */
1169 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1171 if (DECL_TEMPLATE_INSTANTIATION (fn))
1174 || DECL_EXPLICIT_INSTANTIATION (fn))
1176 error ("specialization of %qD after instantiation",
1182 /* This situation should occur only if the first
1183 specialization is an implicit instantiation, the
1184 second is an explicit specialization, and the
1185 implicit instantiation has not yet been used. That
1186 situation can occur if we have implicitly
1187 instantiated a member function and then specialized
1190 We can also wind up here if a friend declaration that
1191 looked like an instantiation turns out to be a
1194 template <class T> void foo(T);
1195 class S { friend void foo<>(int) };
1196 template <> void foo(int);
1198 We transform the existing DECL in place so that any
1199 pointers to it become pointers to the updated
1202 If there was a definition for the template, but not
1203 for the specialization, we want this to look as if
1204 there were no definition, and vice versa. */
1205 DECL_INITIAL (fn) = NULL_TREE;
1206 duplicate_decls (spec, fn, is_friend);
1207 check_specialization_namespace (fn);
1212 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1214 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1215 /* Dup decl failed, but this is a new definition. Set the
1216 line number so any errors match this new
1218 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1224 /* A specialization must be declared in the same namespace as the
1225 template it is specializing. */
1226 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1227 && !check_specialization_namespace (tmpl))
1228 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1230 if (!optimize_specialization_lookup_p (tmpl))
1231 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1232 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1237 /* Unregister the specialization SPEC as a specialization of TMPL.
1238 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1239 if the SPEC was listed as a specialization of TMPL. */
1242 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1246 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1248 s = &TREE_CHAIN (*s))
1249 if (TREE_VALUE (*s) == spec)
1252 *s = TREE_CHAIN (*s);
1254 TREE_VALUE (*s) = new_spec;
1261 /* Compare an entry in the local specializations hash table P1 (which
1262 is really a pointer to a TREE_LIST) with P2 (which is really a
1266 eq_local_specializations (const void *p1, const void *p2)
1268 return TREE_VALUE ((tree) p1) == (tree) p2;
1271 /* Hash P1, an entry in the local specializations table. */
1274 hash_local_specialization (const void* p1)
1276 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1279 /* Like register_specialization, but for local declarations. We are
1280 registering SPEC, an instantiation of TMPL. */
1283 register_local_specialization (tree spec, tree tmpl)
1287 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1288 htab_hash_pointer (tmpl), INSERT);
1289 *slot = build_tree_list (spec, tmpl);
1292 /* Print the list of candidate FNS in an error message. */
1295 print_candidates (tree fns)
1299 const char *str = "candidates are:";
1301 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1305 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1306 error ("%s %+#D", str, OVL_CURRENT (f));
1311 /* Returns the template (one of the functions given by TEMPLATE_ID)
1312 which can be specialized to match the indicated DECL with the
1313 explicit template args given in TEMPLATE_ID. The DECL may be
1314 NULL_TREE if none is available. In that case, the functions in
1315 TEMPLATE_ID are non-members.
1317 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1318 specialization of a member template.
1320 The TEMPLATE_COUNT is the number of references to qualifying
1321 template classes that appeared in the name of the function. See
1322 check_explicit_specialization for a more accurate description.
1324 The template args (those explicitly specified and those deduced)
1325 are output in a newly created vector *TARGS_OUT.
1327 If it is impossible to determine the result, an error message is
1328 issued. The error_mark_node is returned to indicate failure. */
1331 determine_specialization (tree template_id,
1334 int need_member_template,
1339 tree explicit_targs;
1340 tree candidates = NULL_TREE;
1341 tree templates = NULL_TREE;
1343 struct cp_binding_level *b;
1345 *targs_out = NULL_TREE;
1347 if (template_id == error_mark_node)
1348 return error_mark_node;
1350 fns = TREE_OPERAND (template_id, 0);
1351 explicit_targs = TREE_OPERAND (template_id, 1);
1353 if (fns == error_mark_node)
1354 return error_mark_node;
1356 /* Check for baselinks. */
1357 if (BASELINK_P (fns))
1358 fns = BASELINK_FUNCTIONS (fns);
1360 if (!is_overloaded_fn (fns))
1362 error ("%qD is not a function template", fns);
1363 return error_mark_node;
1366 /* Count the number of template headers specified for this
1369 for (b = current_binding_level;
1370 b->kind == sk_template_parms;
1374 for (; fns; fns = OVL_NEXT (fns))
1376 tree fn = OVL_CURRENT (fns);
1378 if (TREE_CODE (fn) == TEMPLATE_DECL)
1380 tree decl_arg_types;
1383 /* DECL might be a specialization of FN. */
1385 /* Adjust the type of DECL in case FN is a static member. */
1386 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1387 if (DECL_STATIC_FUNCTION_P (fn)
1388 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1389 decl_arg_types = TREE_CHAIN (decl_arg_types);
1391 /* Check that the number of function parameters matches.
1393 template <class T> void f(int i = 0);
1394 template <> void f<int>();
1395 The specialization f<int> is invalid but is not caught
1396 by get_bindings below. */
1398 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1399 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1402 /* For a non-static member function, we need to make sure that
1403 the const qualification is the same. This can be done by
1404 checking the 'this' in the argument list. */
1405 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1406 && !same_type_p (TREE_VALUE (fn_arg_types),
1407 TREE_VALUE (decl_arg_types)))
1410 /* In case of explicit specialization, we need to check if
1411 the number of template headers appearing in the specialization
1412 is correct. This is usually done in check_explicit_specialization,
1413 but the check done there cannot be exhaustive when specializing
1414 member functions. Consider the following code:
1416 template <> void A<int>::f(int);
1417 template <> template <> void A<int>::f(int);
1419 Assuming that A<int> is not itself an explicit specialization
1420 already, the first line specializes "f" which is a non-template
1421 member function, whilst the second line specializes "f" which
1422 is a template member function. So both lines are syntactically
1423 correct, and check_explicit_specialization does not reject
1426 Here, we can do better, as we are matching the specialization
1427 against the declarations. We count the number of template
1428 headers, and we check if they match TEMPLATE_COUNT + 1
1429 (TEMPLATE_COUNT is the number of qualifying template classes,
1430 plus there must be another header for the member template
1433 Notice that if header_count is zero, this is not a
1434 specialization but rather a template instantiation, so there
1435 is no check we can perform here. */
1436 if (header_count && header_count != template_count + 1)
1439 /* Check that the number of template arguments at the
1440 innermost level for DECL is the same as for FN. */
1441 if (current_binding_level->kind == sk_template_parms
1442 && !current_binding_level->explicit_spec_p
1443 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1444 != TREE_VEC_LENGTH (TREE_VALUE (current_template_parms))))
1447 /* See whether this function might be a specialization of this
1449 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1452 /* We cannot deduce template arguments that when used to
1453 specialize TMPL will produce DECL. */
1456 /* Save this template, and the arguments deduced. */
1457 templates = tree_cons (targs, fn, templates);
1459 else if (need_member_template)
1460 /* FN is an ordinary member function, and we need a
1461 specialization of a member template. */
1463 else if (TREE_CODE (fn) != FUNCTION_DECL)
1464 /* We can get IDENTIFIER_NODEs here in certain erroneous
1467 else if (!DECL_FUNCTION_MEMBER_P (fn))
1468 /* This is just an ordinary non-member function. Nothing can
1469 be a specialization of that. */
1471 else if (DECL_ARTIFICIAL (fn))
1472 /* Cannot specialize functions that are created implicitly. */
1476 tree decl_arg_types;
1478 /* This is an ordinary member function. However, since
1479 we're here, we can assume it's enclosing class is a
1480 template class. For example,
1482 template <typename T> struct S { void f(); };
1483 template <> void S<int>::f() {}
1485 Here, S<int>::f is a non-template, but S<int> is a
1486 template class. If FN has the same type as DECL, we
1487 might be in business. */
1489 if (!DECL_TEMPLATE_INFO (fn))
1490 /* Its enclosing class is an explicit specialization
1491 of a template class. This is not a candidate. */
1494 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1495 TREE_TYPE (TREE_TYPE (fn))))
1496 /* The return types differ. */
1499 /* Adjust the type of DECL in case FN is a static member. */
1500 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1501 if (DECL_STATIC_FUNCTION_P (fn)
1502 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1503 decl_arg_types = TREE_CHAIN (decl_arg_types);
1505 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1508 candidates = tree_cons (NULL_TREE, fn, candidates);
1512 if (templates && TREE_CHAIN (templates))
1518 It is possible for a specialization with a given function
1519 signature to be instantiated from more than one function
1520 template. In such cases, explicit specification of the
1521 template arguments must be used to uniquely identify the
1522 function template specialization being specialized.
1524 Note that here, there's no suggestion that we're supposed to
1525 determine which of the candidate templates is most
1526 specialized. However, we, also have:
1530 Partial ordering of overloaded function template
1531 declarations is used in the following contexts to select
1532 the function template to which a function template
1533 specialization refers:
1535 -- when an explicit specialization refers to a function
1538 So, we do use the partial ordering rules, at least for now.
1539 This extension can only serve to make invalid programs valid,
1540 so it's safe. And, there is strong anecdotal evidence that
1541 the committee intended the partial ordering rules to apply;
1542 the EDG front-end has that behavior, and John Spicer claims
1543 that the committee simply forgot to delete the wording in
1544 [temp.expl.spec]. */
1545 tree tmpl = most_specialized (templates, decl, explicit_targs);
1546 if (tmpl && tmpl != error_mark_node)
1548 targs = get_bindings (tmpl, decl, explicit_targs, /*check_ret=*/true);
1549 templates = tree_cons (targs, tmpl, NULL_TREE);
1553 if (templates == NULL_TREE && candidates == NULL_TREE)
1555 error ("template-id %qD for %q+D does not match any template "
1556 "declaration", template_id, decl);
1557 return error_mark_node;
1559 else if ((templates && TREE_CHAIN (templates))
1560 || (candidates && TREE_CHAIN (candidates))
1561 || (templates && candidates))
1563 error ("ambiguous template specialization %qD for %q+D",
1565 chainon (candidates, templates);
1566 print_candidates (candidates);
1567 return error_mark_node;
1570 /* We have one, and exactly one, match. */
1573 /* It was a specialization of an ordinary member function in a
1575 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1576 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1579 /* It was a specialization of a template. */
1580 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1581 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1583 *targs_out = copy_node (targs);
1584 SET_TMPL_ARGS_LEVEL (*targs_out,
1585 TMPL_ARGS_DEPTH (*targs_out),
1586 TREE_PURPOSE (templates));
1589 *targs_out = TREE_PURPOSE (templates);
1590 return TREE_VALUE (templates);
1593 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1594 but with the default argument values filled in from those in the
1598 copy_default_args_to_explicit_spec_1 (tree spec_types,
1601 tree new_spec_types;
1606 if (spec_types == void_list_node)
1607 return void_list_node;
1609 /* Substitute into the rest of the list. */
1611 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1612 TREE_CHAIN (tmpl_types));
1614 /* Add the default argument for this parameter. */
1615 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1616 TREE_VALUE (spec_types),
1620 /* DECL is an explicit specialization. Replicate default arguments
1621 from the template it specializes. (That way, code like:
1623 template <class T> void f(T = 3);
1624 template <> void f(double);
1627 works, as required.) An alternative approach would be to look up
1628 the correct default arguments at the call-site, but this approach
1629 is consistent with how implicit instantiations are handled. */
1632 copy_default_args_to_explicit_spec (tree decl)
1637 tree new_spec_types;
1641 tree object_type = NULL_TREE;
1642 tree in_charge = NULL_TREE;
1643 tree vtt = NULL_TREE;
1645 /* See if there's anything we need to do. */
1646 tmpl = DECL_TI_TEMPLATE (decl);
1647 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1648 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1649 if (TREE_PURPOSE (t))
1654 old_type = TREE_TYPE (decl);
1655 spec_types = TYPE_ARG_TYPES (old_type);
1657 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1659 /* Remove the this pointer, but remember the object's type for
1661 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1662 spec_types = TREE_CHAIN (spec_types);
1663 tmpl_types = TREE_CHAIN (tmpl_types);
1665 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1667 /* DECL may contain more parameters than TMPL due to the extra
1668 in-charge parameter in constructors and destructors. */
1669 in_charge = spec_types;
1670 spec_types = TREE_CHAIN (spec_types);
1672 if (DECL_HAS_VTT_PARM_P (decl))
1675 spec_types = TREE_CHAIN (spec_types);
1679 /* Compute the merged default arguments. */
1681 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1683 /* Compute the new FUNCTION_TYPE. */
1687 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1692 /* Put the in-charge parameter back. */
1693 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1694 TREE_VALUE (in_charge),
1697 new_type = build_method_type_directly (object_type,
1698 TREE_TYPE (old_type),
1702 new_type = build_function_type (TREE_TYPE (old_type),
1704 new_type = cp_build_type_attribute_variant (new_type,
1705 TYPE_ATTRIBUTES (old_type));
1706 new_type = build_exception_variant (new_type,
1707 TYPE_RAISES_EXCEPTIONS (old_type));
1708 TREE_TYPE (decl) = new_type;
1711 /* Check to see if the function just declared, as indicated in
1712 DECLARATOR, and in DECL, is a specialization of a function
1713 template. We may also discover that the declaration is an explicit
1714 instantiation at this point.
1716 Returns DECL, or an equivalent declaration that should be used
1717 instead if all goes well. Issues an error message if something is
1718 amiss. Returns error_mark_node if the error is not easily
1721 FLAGS is a bitmask consisting of the following flags:
1723 2: The function has a definition.
1724 4: The function is a friend.
1726 The TEMPLATE_COUNT is the number of references to qualifying
1727 template classes that appeared in the name of the function. For
1730 template <class T> struct S { void f(); };
1733 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1734 classes are not counted in the TEMPLATE_COUNT, so that in
1736 template <class T> struct S {};
1737 template <> struct S<int> { void f(); }
1738 template <> void S<int>::f();
1740 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1741 invalid; there should be no template <>.)
1743 If the function is a specialization, it is marked as such via
1744 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1745 is set up correctly, and it is added to the list of specializations
1746 for that template. */
1749 check_explicit_specialization (tree declarator,
1754 int have_def = flags & 2;
1755 int is_friend = flags & 4;
1756 int specialization = 0;
1757 int explicit_instantiation = 0;
1758 int member_specialization = 0;
1759 tree ctype = DECL_CLASS_CONTEXT (decl);
1760 tree dname = DECL_NAME (decl);
1765 if (!processing_specialization)
1768 tsk = tsk_excessive_parms;
1771 tsk = current_tmpl_spec_kind (template_count);
1776 if (processing_specialization)
1779 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1781 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1784 /* This could be something like:
1786 template <class T> void f(T);
1787 class S { friend void f<>(int); } */
1791 /* This case handles bogus declarations like template <>
1792 template <class T> void f<int>(); */
1794 error ("template-id %qD in declaration of primary template",
1801 case tsk_invalid_member_spec:
1802 /* The error has already been reported in
1803 check_specialization_scope. */
1804 return error_mark_node;
1806 case tsk_invalid_expl_inst:
1807 error ("template parameter list used in explicit instantiation");
1813 error ("definition provided for explicit instantiation");
1815 explicit_instantiation = 1;
1818 case tsk_excessive_parms:
1819 case tsk_insufficient_parms:
1820 if (tsk == tsk_excessive_parms)
1821 error ("too many template parameter lists in declaration of %qD",
1823 else if (template_header_count)
1824 error("too few template parameter lists in declaration of %qD", decl);
1826 error("explicit specialization of %qD must be introduced by "
1827 "%<template <>%>", decl);
1831 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1833 member_specialization = 1;
1839 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1841 /* This case handles bogus declarations like template <>
1842 template <class T> void f<int>(); */
1844 if (uses_template_parms (declarator))
1845 error ("function template partial specialization %qD "
1846 "is not allowed", declarator);
1848 error ("template-id %qD in declaration of primary template",
1853 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1854 /* This is a specialization of a member template, without
1855 specialization the containing class. Something like:
1857 template <class T> struct S {
1858 template <class U> void f (U);
1860 template <> template <class U> void S<int>::f(U) {}
1862 That's a specialization -- but of the entire template. */
1870 if (specialization || member_specialization)
1872 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1873 for (; t; t = TREE_CHAIN (t))
1874 if (TREE_PURPOSE (t))
1877 ("default argument specified in explicit specialization");
1880 if (current_lang_name == lang_name_c)
1881 error ("template specialization with C linkage");
1884 if (specialization || member_specialization || explicit_instantiation)
1886 tree tmpl = NULL_TREE;
1887 tree targs = NULL_TREE;
1889 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1890 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1894 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1899 /* If there is no class context, the explicit instantiation
1900 must be at namespace scope. */
1901 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1903 /* Find the namespace binding, using the declaration
1905 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1906 if (!fns || !is_overloaded_fn (fns))
1908 error ("%qD is not a template function", dname);
1909 fns = error_mark_node;
1913 declarator = lookup_template_function (fns, NULL_TREE);
1916 if (declarator == error_mark_node)
1917 return error_mark_node;
1919 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1921 if (!explicit_instantiation)
1922 /* A specialization in class scope. This is invalid,
1923 but the error will already have been flagged by
1924 check_specialization_scope. */
1925 return error_mark_node;
1928 /* It's not valid to write an explicit instantiation in
1931 class C { template void f(); }
1933 This case is caught by the parser. However, on
1936 template class C { void f(); };
1938 (which is invalid) we can get here. The error will be
1945 else if (ctype != NULL_TREE
1946 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1949 /* Find the list of functions in ctype that have the same
1950 name as the declared function. */
1951 tree name = TREE_OPERAND (declarator, 0);
1952 tree fns = NULL_TREE;
1955 if (constructor_name_p (name, ctype))
1957 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1959 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1960 : !CLASSTYPE_DESTRUCTORS (ctype))
1962 /* From [temp.expl.spec]:
1964 If such an explicit specialization for the member
1965 of a class template names an implicitly-declared
1966 special member function (clause _special_), the
1967 program is ill-formed.
1969 Similar language is found in [temp.explicit]. */
1970 error ("specialization of implicitly-declared special member function");
1971 return error_mark_node;
1974 name = is_constructor ? ctor_identifier : dtor_identifier;
1977 if (!DECL_CONV_FN_P (decl))
1979 idx = lookup_fnfields_1 (ctype, name);
1981 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1985 VEC(tree,gc) *methods;
1988 /* For a type-conversion operator, we cannot do a
1989 name-based lookup. We might be looking for `operator
1990 int' which will be a specialization of `operator T'.
1991 So, we find *all* the conversion operators, and then
1992 select from them. */
1995 methods = CLASSTYPE_METHOD_VEC (ctype);
1997 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1998 VEC_iterate (tree, methods, idx, ovl);
2001 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2002 /* There are no more conversion functions. */
2005 /* Glue all these conversion functions together
2006 with those we already have. */
2007 for (; ovl; ovl = OVL_NEXT (ovl))
2008 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2012 if (fns == NULL_TREE)
2014 error ("no member function %qD declared in %qT", name, ctype);
2015 return error_mark_node;
2018 TREE_OPERAND (declarator, 0) = fns;
2021 /* Figure out what exactly is being specialized at this point.
2022 Note that for an explicit instantiation, even one for a
2023 member function, we cannot tell apriori whether the
2024 instantiation is for a member template, or just a member
2025 function of a template class. Even if a member template is
2026 being instantiated, the member template arguments may be
2027 elided if they can be deduced from the rest of the
2029 tmpl = determine_specialization (declarator, decl,
2031 member_specialization,
2034 if (!tmpl || tmpl == error_mark_node)
2035 /* We couldn't figure out what this declaration was
2037 return error_mark_node;
2040 tree gen_tmpl = most_general_template (tmpl);
2042 if (explicit_instantiation)
2044 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2045 is done by do_decl_instantiation later. */
2047 int arg_depth = TMPL_ARGS_DEPTH (targs);
2048 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2050 if (arg_depth > parm_depth)
2052 /* If TMPL is not the most general template (for
2053 example, if TMPL is a friend template that is
2054 injected into namespace scope), then there will
2055 be too many levels of TARGS. Remove some of them
2060 new_targs = make_tree_vec (parm_depth);
2061 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2062 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2063 = TREE_VEC_ELT (targs, i);
2067 return instantiate_template (tmpl, targs, tf_error);
2070 /* If we thought that the DECL was a member function, but it
2071 turns out to be specializing a static member function,
2072 make DECL a static member function as well. */
2073 if (DECL_STATIC_FUNCTION_P (tmpl)
2074 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2075 revert_static_member_fn (decl);
2077 /* If this is a specialization of a member template of a
2078 template class. In we want to return the TEMPLATE_DECL,
2079 not the specialization of it. */
2080 if (tsk == tsk_template)
2082 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2083 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2086 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2087 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2088 = DECL_SOURCE_LOCATION (decl);
2089 /* We want to use the argument list specified in the
2090 definition, not in the original declaration. */
2091 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2092 = DECL_ARGUMENTS (decl);
2097 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2098 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2100 /* Inherit default function arguments from the template
2101 DECL is specializing. */
2102 copy_default_args_to_explicit_spec (decl);
2104 /* This specialization has the same protection as the
2105 template it specializes. */
2106 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2107 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2108 /* The specialization has the same visibility as the
2109 template it specializes. */
2110 if (DECL_VISIBILITY_SPECIFIED (gen_tmpl))
2112 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2113 DECL_VISIBILITY (decl) = DECL_VISIBILITY (gen_tmpl);
2115 /* If DECL is a friend declaration, declared using an
2116 unqualified name, the namespace associated with DECL may
2117 have been set incorrectly. For example, in:
2119 template <typename T> void f(T);
2121 struct S { friend void f<int>(int); }
2124 we will have set the DECL_CONTEXT for the friend
2125 declaration to N, rather than to the global namespace. */
2126 if (DECL_NAMESPACE_SCOPE_P (decl))
2127 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2129 if (is_friend && !have_def)
2130 /* This is not really a declaration of a specialization.
2131 It's just the name of an instantiation. But, it's not
2132 a request for an instantiation, either. */
2133 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2134 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2135 /* This is indeed a specialization. In case of constructors
2136 and destructors, we need in-charge and not-in-charge
2137 versions in V3 ABI. */
2138 clone_function_decl (decl, /*update_method_vec_p=*/0);
2140 /* Register this specialization so that we can find it
2142 decl = register_specialization (decl, gen_tmpl, targs, is_friend);
2149 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2150 parameters. These are represented in the same format used for
2151 DECL_TEMPLATE_PARMS. */
2154 comp_template_parms (tree parms1, tree parms2)
2159 if (parms1 == parms2)
2162 for (p1 = parms1, p2 = parms2;
2163 p1 != NULL_TREE && p2 != NULL_TREE;
2164 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2166 tree t1 = TREE_VALUE (p1);
2167 tree t2 = TREE_VALUE (p2);
2170 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2171 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2173 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2176 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2178 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2179 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2181 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2184 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2186 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2191 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2192 /* One set of parameters has more parameters lists than the
2199 /* Complain if DECL shadows a template parameter.
2201 [temp.local]: A template-parameter shall not be redeclared within its
2202 scope (including nested scopes). */
2205 check_template_shadow (tree decl)
2209 /* If we're not in a template, we can't possibly shadow a template
2211 if (!current_template_parms)
2214 /* Figure out what we're shadowing. */
2215 if (TREE_CODE (decl) == OVERLOAD)
2216 decl = OVL_CURRENT (decl);
2217 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2219 /* If there's no previous binding for this name, we're not shadowing
2220 anything, let alone a template parameter. */
2224 /* If we're not shadowing a template parameter, we're done. Note
2225 that OLDDECL might be an OVERLOAD (or perhaps even an
2226 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2228 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2231 /* We check for decl != olddecl to avoid bogus errors for using a
2232 name inside a class. We check TPFI to avoid duplicate errors for
2233 inline member templates. */
2235 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2238 error ("declaration of %q+#D", decl);
2239 error (" shadows template parm %q+#D", olddecl);
2242 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2243 ORIG_LEVEL, DECL, and TYPE. */
2246 build_template_parm_index (int index,
2252 tree t = make_node (TEMPLATE_PARM_INDEX);
2253 TEMPLATE_PARM_IDX (t) = index;
2254 TEMPLATE_PARM_LEVEL (t) = level;
2255 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2256 TEMPLATE_PARM_DECL (t) = decl;
2257 TREE_TYPE (t) = type;
2258 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2259 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2260 TREE_READONLY (t) = TREE_READONLY (decl);
2265 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2266 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2267 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2268 new one is created. */
2271 reduce_template_parm_level (tree index, tree type, int levels)
2273 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2274 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2275 != TEMPLATE_PARM_LEVEL (index) - levels))
2277 tree orig_decl = TEMPLATE_PARM_DECL (index);
2280 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2281 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2282 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2283 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2284 DECL_ARTIFICIAL (decl) = 1;
2285 SET_DECL_TEMPLATE_PARM_P (decl);
2287 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2288 TEMPLATE_PARM_LEVEL (index) - levels,
2289 TEMPLATE_PARM_ORIG_LEVEL (index),
2291 TEMPLATE_PARM_DESCENDANTS (index) = t;
2293 /* Template template parameters need this. */
2294 if (TREE_CODE (decl) != CONST_DECL)
2295 DECL_TEMPLATE_PARMS (decl)
2296 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2299 return TEMPLATE_PARM_DESCENDANTS (index);
2302 /* Process information from new template parameter NEXT and append it to the
2303 LIST being built. This new parameter is a non-type parameter iff
2304 IS_NON_TYPE is true. */
2307 process_template_parm (tree list, tree next, bool is_non_type)
2315 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2316 defval = TREE_PURPOSE (parm);
2320 tree p = TREE_VALUE (tree_last (list));
2322 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2323 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2325 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2333 parm = TREE_VALUE (parm);
2335 SET_DECL_TEMPLATE_PARM_P (parm);
2339 The top-level cv-qualifiers on the template-parameter are
2340 ignored when determining its type. */
2341 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2343 /* A template parameter is not modifiable. */
2344 TREE_CONSTANT (parm) = 1;
2345 TREE_INVARIANT (parm) = 1;
2346 TREE_READONLY (parm) = 1;
2347 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2348 TREE_TYPE (parm) = void_type_node;
2349 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2350 TREE_CONSTANT (decl) = 1;
2351 TREE_INVARIANT (decl) = 1;
2352 TREE_READONLY (decl) = 1;
2353 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2354 = build_template_parm_index (idx, processing_template_decl,
2355 processing_template_decl,
2356 decl, TREE_TYPE (parm));
2361 parm = TREE_VALUE (TREE_VALUE (parm));
2363 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2365 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2366 /* This is for distinguishing between real templates and template
2367 template parameters */
2368 TREE_TYPE (parm) = t;
2369 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2374 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2375 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2376 decl = build_decl (TYPE_DECL, parm, t);
2379 TYPE_NAME (t) = decl;
2380 TYPE_STUB_DECL (t) = decl;
2382 TEMPLATE_TYPE_PARM_INDEX (t)
2383 = build_template_parm_index (idx, processing_template_decl,
2384 processing_template_decl,
2385 decl, TREE_TYPE (parm));
2387 DECL_ARTIFICIAL (decl) = 1;
2388 SET_DECL_TEMPLATE_PARM_P (decl);
2390 parm = build_tree_list (defval, parm);
2391 return chainon (list, parm);
2394 /* The end of a template parameter list has been reached. Process the
2395 tree list into a parameter vector, converting each parameter into a more
2396 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2400 end_template_parm_list (tree parms)
2404 tree saved_parmlist = make_tree_vec (list_length (parms));
2406 current_template_parms
2407 = tree_cons (size_int (processing_template_decl),
2408 saved_parmlist, current_template_parms);
2410 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2412 next = TREE_CHAIN (parm);
2413 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2414 TREE_CHAIN (parm) = NULL_TREE;
2417 --processing_template_parmlist;
2419 return saved_parmlist;
2422 /* end_template_decl is called after a template declaration is seen. */
2425 end_template_decl (void)
2427 reset_specialization ();
2429 if (! processing_template_decl)
2432 /* This matches the pushlevel in begin_template_parm_list. */
2435 --processing_template_decl;
2436 current_template_parms = TREE_CHAIN (current_template_parms);
2439 /* Given a template argument vector containing the template PARMS.
2440 The innermost PARMS are given first. */
2443 current_template_args (void)
2446 tree args = NULL_TREE;
2447 int length = TMPL_PARMS_DEPTH (current_template_parms);
2450 /* If there is only one level of template parameters, we do not
2451 create a TREE_VEC of TREE_VECs. Instead, we return a single
2452 TREE_VEC containing the arguments. */
2454 args = make_tree_vec (length);
2456 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2458 tree a = copy_node (TREE_VALUE (header));
2461 TREE_TYPE (a) = NULL_TREE;
2462 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2464 tree t = TREE_VEC_ELT (a, i);
2466 /* T will be a list if we are called from within a
2467 begin/end_template_parm_list pair, but a vector directly
2468 if within a begin/end_member_template_processing pair. */
2469 if (TREE_CODE (t) == TREE_LIST)
2473 if (TREE_CODE (t) == TYPE_DECL
2474 || TREE_CODE (t) == TEMPLATE_DECL)
2477 t = DECL_INITIAL (t);
2478 TREE_VEC_ELT (a, i) = t;
2483 TREE_VEC_ELT (args, --l) = a;
2491 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2492 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2493 a member template. Used by push_template_decl below. */
2496 build_template_decl (tree decl, tree parms, bool member_template_p)
2498 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2499 DECL_TEMPLATE_PARMS (tmpl) = parms;
2500 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2501 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2502 if (DECL_LANG_SPECIFIC (decl))
2504 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2505 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2506 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2507 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2508 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2509 if (DECL_OVERLOADED_OPERATOR_P (decl))
2510 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2511 DECL_OVERLOADED_OPERATOR_P (decl));
2517 struct template_parm_data
2519 /* The level of the template parameters we are currently
2523 /* The index of the specialization argument we are currently
2527 /* An array whose size is the number of template parameters. The
2528 elements are nonzero if the parameter has been used in any one
2529 of the arguments processed so far. */
2532 /* An array whose size is the number of template arguments. The
2533 elements are nonzero if the argument makes use of template
2534 parameters of this level. */
2535 int* arg_uses_template_parms;
2538 /* Subroutine of push_template_decl used to see if each template
2539 parameter in a partial specialization is used in the explicit
2540 argument list. If T is of the LEVEL given in DATA (which is
2541 treated as a template_parm_data*), then DATA->PARMS is marked
2545 mark_template_parm (tree t, void* data)
2549 struct template_parm_data* tpd = (struct template_parm_data*) data;
2551 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2553 level = TEMPLATE_PARM_LEVEL (t);
2554 idx = TEMPLATE_PARM_IDX (t);
2558 level = TEMPLATE_TYPE_LEVEL (t);
2559 idx = TEMPLATE_TYPE_IDX (t);
2562 if (level == tpd->level)
2564 tpd->parms[idx] = 1;
2565 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2568 /* Return zero so that for_each_template_parm will continue the
2569 traversal of the tree; we want to mark *every* template parm. */
2573 /* Process the partial specialization DECL. */
2576 process_partial_specialization (tree decl)
2578 tree type = TREE_TYPE (decl);
2579 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2580 tree specargs = CLASSTYPE_TI_ARGS (type);
2581 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2582 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2583 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2584 int nargs = TREE_VEC_LENGTH (inner_args);
2585 int ntparms = TREE_VEC_LENGTH (inner_parms);
2587 int did_error_intro = 0;
2588 struct template_parm_data tpd;
2589 struct template_parm_data tpd2;
2591 /* We check that each of the template parameters given in the
2592 partial specialization is used in the argument list to the
2593 specialization. For example:
2595 template <class T> struct S;
2596 template <class T> struct S<T*>;
2598 The second declaration is OK because `T*' uses the template
2599 parameter T, whereas
2601 template <class T> struct S<int>;
2603 is no good. Even trickier is:
2614 The S2<T> declaration is actually invalid; it is a
2615 full-specialization. Of course,
2618 struct S2<T (*)(U)>;
2620 or some such would have been OK. */
2621 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2622 tpd.parms = alloca (sizeof (int) * ntparms);
2623 memset (tpd.parms, 0, sizeof (int) * ntparms);
2625 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2626 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2627 for (i = 0; i < nargs; ++i)
2629 tpd.current_arg = i;
2630 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2631 &mark_template_parm,
2635 for (i = 0; i < ntparms; ++i)
2636 if (tpd.parms[i] == 0)
2638 /* One of the template parms was not used in the
2640 if (!did_error_intro)
2642 error ("template parameters not used in partial specialization:");
2643 did_error_intro = 1;
2646 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2649 /* [temp.class.spec]
2651 The argument list of the specialization shall not be identical to
2652 the implicit argument list of the primary template. */
2653 if (comp_template_args
2655 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2657 error ("partial specialization %qT does not specialize any template arguments", type);
2659 /* [temp.class.spec]
2661 A partially specialized non-type argument expression shall not
2662 involve template parameters of the partial specialization except
2663 when the argument expression is a simple identifier.
2665 The type of a template parameter corresponding to a specialized
2666 non-type argument shall not be dependent on a parameter of the
2668 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2670 for (i = 0; i < nargs; ++i)
2672 tree arg = TREE_VEC_ELT (inner_args, i);
2673 if (/* These first two lines are the `non-type' bit. */
2675 && TREE_CODE (arg) != TEMPLATE_DECL
2676 /* This next line is the `argument expression is not just a
2677 simple identifier' condition and also the `specialized
2678 non-type argument' bit. */
2679 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2681 if (tpd.arg_uses_template_parms[i])
2682 error ("template argument %qE involves template parameter(s)", arg);
2685 /* Look at the corresponding template parameter,
2686 marking which template parameters its type depends
2689 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2694 /* We haven't yet initialized TPD2. Do so now. */
2695 tpd2.arg_uses_template_parms
2696 = alloca (sizeof (int) * nargs);
2697 /* The number of parameters here is the number in the
2698 main template, which, as checked in the assertion
2700 tpd2.parms = alloca (sizeof (int) * nargs);
2702 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2705 /* Mark the template parameters. But this time, we're
2706 looking for the template parameters of the main
2707 template, not in the specialization. */
2708 tpd2.current_arg = i;
2709 tpd2.arg_uses_template_parms[i] = 0;
2710 memset (tpd2.parms, 0, sizeof (int) * nargs);
2711 for_each_template_parm (type,
2712 &mark_template_parm,
2716 if (tpd2.arg_uses_template_parms [i])
2718 /* The type depended on some template parameters.
2719 If they are fully specialized in the
2720 specialization, that's OK. */
2722 for (j = 0; j < nargs; ++j)
2723 if (tpd2.parms[j] != 0
2724 && tpd.arg_uses_template_parms [j])
2726 error ("type %qT of template argument %qE depends "
2727 "on template parameter(s)",
2737 if (retrieve_specialization (maintmpl, specargs,
2738 /*class_specializations_p=*/true))
2739 /* We've already got this specialization. */
2742 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2743 = tree_cons (inner_args, inner_parms,
2744 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2745 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2749 /* Check that a template declaration's use of default arguments is not
2750 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2751 nonzero if DECL is the thing declared by a primary template.
2752 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2755 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2758 int last_level_to_check;
2763 A default template-argument shall not be specified in a
2764 function template declaration or a function template definition, nor
2765 in the template-parameter-list of the definition of a member of a
2768 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2769 /* You can't have a function template declaration in a local
2770 scope, nor you can you define a member of a class template in a
2774 if (current_class_type
2775 && !TYPE_BEING_DEFINED (current_class_type)
2776 && DECL_LANG_SPECIFIC (decl)
2777 /* If this is either a friend defined in the scope of the class
2778 or a member function. */
2779 && (DECL_FUNCTION_MEMBER_P (decl)
2780 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2781 : DECL_FRIEND_CONTEXT (decl)
2782 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2784 /* And, if it was a member function, it really was defined in
2785 the scope of the class. */
2786 && (!DECL_FUNCTION_MEMBER_P (decl)
2787 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2788 /* We already checked these parameters when the template was
2789 declared, so there's no need to do it again now. This function
2790 was defined in class scope, but we're processing it's body now
2791 that the class is complete. */
2796 If a template-parameter has a default template-argument, all
2797 subsequent template-parameters shall have a default
2798 template-argument supplied. */
2799 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2801 tree inner_parms = TREE_VALUE (parm_level);
2802 int ntparms = TREE_VEC_LENGTH (inner_parms);
2803 int seen_def_arg_p = 0;
2806 for (i = 0; i < ntparms; ++i)
2808 tree parm = TREE_VEC_ELT (inner_parms, i);
2809 if (TREE_PURPOSE (parm))
2811 else if (seen_def_arg_p)
2813 error ("no default argument for %qD", TREE_VALUE (parm));
2814 /* For better subsequent error-recovery, we indicate that
2815 there should have been a default argument. */
2816 TREE_PURPOSE (parm) = error_mark_node;
2821 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2822 /* For an ordinary class template, default template arguments are
2823 allowed at the innermost level, e.g.:
2824 template <class T = int>
2826 but, in a partial specialization, they're not allowed even
2827 there, as we have in [temp.class.spec]:
2829 The template parameter list of a specialization shall not
2830 contain default template argument values.
2832 So, for a partial specialization, or for a function template,
2833 we look at all of them. */
2836 /* But, for a primary class template that is not a partial
2837 specialization we look at all template parameters except the
2839 parms = TREE_CHAIN (parms);
2841 /* Figure out what error message to issue. */
2842 if (TREE_CODE (decl) == FUNCTION_DECL)
2843 msg = "default template arguments may not be used in function templates";
2844 else if (is_partial)
2845 msg = "default template arguments may not be used in partial specializations";
2847 msg = "default argument for template parameter for class enclosing %qD";
2849 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2850 /* If we're inside a class definition, there's no need to
2851 examine the parameters to the class itself. On the one
2852 hand, they will be checked when the class is defined, and,
2853 on the other, default arguments are valid in things like:
2854 template <class T = double>
2855 struct S { template <class U> void f(U); };
2856 Here the default argument for `S' has no bearing on the
2857 declaration of `f'. */
2858 last_level_to_check = template_class_depth (current_class_type) + 1;
2860 /* Check everything. */
2861 last_level_to_check = 0;
2863 for (parm_level = parms;
2864 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2865 parm_level = TREE_CHAIN (parm_level))
2867 tree inner_parms = TREE_VALUE (parm_level);
2871 ntparms = TREE_VEC_LENGTH (inner_parms);
2872 for (i = 0; i < ntparms; ++i)
2873 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2881 /* Clear out the default argument so that we are not
2883 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2886 /* At this point, if we're still interested in issuing messages,
2887 they must apply to classes surrounding the object declared. */
2889 msg = "default argument for template parameter for class enclosing %qD";
2893 /* Worker for push_template_decl_real, called via
2894 for_each_template_parm. DATA is really an int, indicating the
2895 level of the parameters we are interested in. If T is a template
2896 parameter of that level, return nonzero. */
2899 template_parm_this_level_p (tree t, void* data)
2901 int this_level = *(int *)data;
2904 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2905 level = TEMPLATE_PARM_LEVEL (t);
2907 level = TEMPLATE_TYPE_LEVEL (t);
2908 return level == this_level;
2911 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2912 parameters given by current_template_args, or reuses a
2913 previously existing one, if appropriate. Returns the DECL, or an
2914 equivalent one, if it is replaced via a call to duplicate_decls.
2916 If IS_FRIEND is true, DECL is a friend declaration. */
2919 push_template_decl_real (tree decl, bool is_friend)
2927 int new_template_p = 0;
2928 /* True if the template is a member template, in the sense of
2930 bool member_template_p = false;
2932 if (decl == error_mark_node)
2935 /* See if this is a partial specialization. */
2936 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2937 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2938 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2940 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
2944 /* For a friend, we want the context of the friend function, not
2945 the type of which it is a friend. */
2946 ctx = DECL_CONTEXT (decl);
2947 else if (CP_DECL_CONTEXT (decl)
2948 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2949 /* In the case of a virtual function, we want the class in which
2951 ctx = CP_DECL_CONTEXT (decl);
2953 /* Otherwise, if we're currently defining some class, the DECL
2954 is assumed to be a member of the class. */
2955 ctx = current_scope ();
2957 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2960 if (!DECL_CONTEXT (decl))
2961 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2963 /* See if this is a primary template. */
2964 primary = template_parm_scope_p ();
2968 if (DECL_CLASS_SCOPE_P (decl))
2969 member_template_p = true;
2970 if (current_lang_name == lang_name_c)
2971 error ("template with C linkage");
2972 else if (TREE_CODE (decl) == TYPE_DECL
2973 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2974 error ("template class without a name");
2975 else if (TREE_CODE (decl) == FUNCTION_DECL)
2977 if (DECL_DESTRUCTOR_P (decl))
2981 A destructor shall not be a member template. */
2982 error ("destructor %qD declared as member template", decl);
2983 return error_mark_node;
2985 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
2986 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
2987 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
2988 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
2989 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
2990 == void_list_node)))
2992 /* [basic.stc.dynamic.allocation]
2994 An allocation function can be a function
2995 template. ... Template allocation functions shall
2996 have two or more parameters. */
2997 error ("invalid template declaration of %qD", decl);
3001 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
3002 && CLASS_TYPE_P (TREE_TYPE (decl)))
3003 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx)))
3007 error ("template declaration of %q#D", decl);
3008 return error_mark_node;
3012 /* Check to see that the rules regarding the use of default
3013 arguments are not being violated. */
3014 check_default_tmpl_args (decl, current_template_parms,
3015 primary, is_partial);
3018 return process_partial_specialization (decl);
3020 args = current_template_args ();
3023 || TREE_CODE (ctx) == FUNCTION_DECL
3024 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3025 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3027 if (DECL_LANG_SPECIFIC (decl)
3028 && DECL_TEMPLATE_INFO (decl)
3029 && DECL_TI_TEMPLATE (decl))
3030 tmpl = DECL_TI_TEMPLATE (decl);
3031 /* If DECL is a TYPE_DECL for a class-template, then there won't
3032 be DECL_LANG_SPECIFIC. The information equivalent to
3033 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3034 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3035 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3036 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3038 /* Since a template declaration already existed for this
3039 class-type, we must be redeclaring it here. Make sure
3040 that the redeclaration is valid. */
3041 redeclare_class_template (TREE_TYPE (decl),
3042 current_template_parms);
3043 /* We don't need to create a new TEMPLATE_DECL; just use the
3044 one we already had. */
3045 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3049 tmpl = build_template_decl (decl, current_template_parms,
3053 if (DECL_LANG_SPECIFIC (decl)
3054 && DECL_TEMPLATE_SPECIALIZATION (decl))
3056 /* A specialization of a member template of a template
3058 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3059 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3060 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3066 tree a, t, current, parms;
3069 if (TREE_CODE (decl) == TYPE_DECL)
3071 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3072 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3073 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3074 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3075 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3078 error ("%qD does not declare a template type", decl);
3082 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3084 error ("template definition of non-template %q#D", decl);
3088 tmpl = DECL_TI_TEMPLATE (decl);
3090 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3091 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3092 && DECL_TEMPLATE_SPECIALIZATION (decl)
3093 && DECL_MEMBER_TEMPLATE_P (tmpl))
3097 /* The declaration is a specialization of a member
3098 template, declared outside the class. Therefore, the
3099 innermost template arguments will be NULL, so we
3100 replace them with the arguments determined by the
3101 earlier call to check_explicit_specialization. */
3102 args = DECL_TI_ARGS (decl);
3105 = build_template_decl (decl, current_template_parms,
3107 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3108 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3109 DECL_TI_TEMPLATE (decl) = new_tmpl;
3110 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3111 DECL_TEMPLATE_INFO (new_tmpl)
3112 = tree_cons (tmpl, args, NULL_TREE);
3114 register_specialization (new_tmpl,
3115 most_general_template (tmpl),
3121 /* Make sure the template headers we got make sense. */
3123 parms = DECL_TEMPLATE_PARMS (tmpl);
3124 i = TMPL_PARMS_DEPTH (parms);
3125 if (TMPL_ARGS_DEPTH (args) != i)
3127 error ("expected %d levels of template parms for %q#D, got %d",
3128 i, decl, TMPL_ARGS_DEPTH (args));
3131 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3133 a = TMPL_ARGS_LEVEL (args, i);
3134 t = INNERMOST_TEMPLATE_PARMS (parms);
3136 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3138 if (current == decl)
3139 error ("got %d template parameters for %q#D",
3140 TREE_VEC_LENGTH (a), decl);
3142 error ("got %d template parameters for %q#T",
3143 TREE_VEC_LENGTH (a), current);
3144 error (" but %d required", TREE_VEC_LENGTH (t));
3145 return error_mark_node;
3148 /* Perhaps we should also check that the parms are used in the
3149 appropriate qualifying scopes in the declarator? */
3151 if (current == decl)
3154 current = TYPE_CONTEXT (current);
3158 DECL_TEMPLATE_RESULT (tmpl) = decl;
3159 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3161 /* Push template declarations for global functions and types. Note
3162 that we do not try to push a global template friend declared in a
3163 template class; such a thing may well depend on the template
3164 parameters of the class. */
3165 if (new_template_p && !ctx
3166 && !(is_friend && template_class_depth (current_class_type) > 0))
3168 tmpl = pushdecl_namespace_level (tmpl, is_friend);
3169 if (tmpl == error_mark_node)
3170 return error_mark_node;
3172 /* Hide template friend classes that haven't been declared yet. */
3173 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
3175 DECL_ANTICIPATED (tmpl) = 1;
3176 DECL_FRIEND_P (tmpl) = 1;
3182 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3183 if (DECL_CONV_FN_P (tmpl))
3185 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3187 /* It is a conversion operator. See if the type converted to
3188 depends on innermost template operands. */
3190 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3192 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3196 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3197 back to its most general template. If TMPL is a specialization,
3198 ARGS may only have the innermost set of arguments. Add the missing
3199 argument levels if necessary. */
3200 if (DECL_TEMPLATE_INFO (tmpl))
3201 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3203 info = tree_cons (tmpl, args, NULL_TREE);
3205 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3207 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3208 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3209 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3210 /* Don't change the name if we've already set it up. */
3211 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3212 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3214 else if (DECL_LANG_SPECIFIC (decl))
3215 DECL_TEMPLATE_INFO (decl) = info;
3217 return DECL_TEMPLATE_RESULT (tmpl);
3221 push_template_decl (tree decl)
3223 return push_template_decl_real (decl, false);
3226 /* Called when a class template TYPE is redeclared with the indicated
3227 template PARMS, e.g.:
3229 template <class T> struct S;
3230 template <class T> struct S {}; */
3233 redeclare_class_template (tree type, tree parms)
3239 if (!TYPE_TEMPLATE_INFO (type))
3241 error ("%qT is not a template type", type);
3245 tmpl = TYPE_TI_TEMPLATE (type);
3246 if (!PRIMARY_TEMPLATE_P (tmpl))
3247 /* The type is nested in some template class. Nothing to worry
3248 about here; there are no new template parameters for the nested
3254 error ("template specifiers not specified in declaration of %qD",
3259 parms = INNERMOST_TEMPLATE_PARMS (parms);
3260 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3262 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3264 error ("previous declaration %q+D", tmpl);
3265 error ("used %d template parameter(s) instead of %d",
3266 TREE_VEC_LENGTH (tmpl_parms),
3267 TREE_VEC_LENGTH (parms));
3271 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3273 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3274 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3275 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3276 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3278 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3280 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3281 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3282 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3284 error ("template parameter %q+#D", tmpl_parm);
3285 error ("redeclared here as %q#D", parm);
3289 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3291 /* We have in [temp.param]:
3293 A template-parameter may not be given default arguments
3294 by two different declarations in the same scope. */
3295 error ("redefinition of default argument for %q#D", parm);
3296 error ("%J original definition appeared here", tmpl_parm);
3300 if (parm_default != NULL_TREE)
3301 /* Update the previous template parameters (which are the ones
3302 that will really count) with the new default value. */
3303 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3304 else if (tmpl_default != NULL_TREE)
3305 /* Update the new parameters, too; they'll be used as the
3306 parameters for any members. */
3307 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3311 /* Simplify EXPR if it is a non-dependent expression. Returns the
3312 (possibly simplified) expression. */
3315 fold_non_dependent_expr (tree expr)
3317 /* If we're in a template, but EXPR isn't value dependent, simplify
3318 it. We're supposed to treat:
3320 template <typename T> void f(T[1 + 1]);
3321 template <typename T> void f(T[2]);
3323 as two declarations of the same function, for example. */
3324 if (processing_template_decl
3325 && !type_dependent_expression_p (expr)
3326 && !value_dependent_expression_p (expr))
3328 HOST_WIDE_INT saved_processing_template_decl;
3330 saved_processing_template_decl = processing_template_decl;
3331 processing_template_decl = 0;
3332 expr = tsubst_copy_and_build (expr,
3335 /*in_decl=*/NULL_TREE,
3336 /*function_p=*/false);
3337 processing_template_decl = saved_processing_template_decl;
3342 /* EXPR is an expression which is used in a constant-expression context.
3343 For instance, it could be a VAR_DECL with a constant initializer.
3344 Extract the innest constant expression.
3346 This is basically a more powerful version of
3347 integral_constant_value, which can be used also in templates where
3348 initializers can maintain a syntactic rather than semantic form
3349 (even if they are non-dependent, for access-checking purposes). */
3352 fold_decl_constant_value (tree expr)
3354 tree const_expr = expr;
3357 expr = fold_non_dependent_expr (const_expr);
3358 const_expr = integral_constant_value (expr);
3360 while (expr != const_expr);
3365 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3366 must be a function or a pointer-to-function type, as specified
3367 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3368 and check that the resulting function has external linkage. */
3371 convert_nontype_argument_function (tree type, tree expr)
3376 fn = instantiate_type (type, fns, tf_none);
3377 if (fn == error_mark_node)
3378 return error_mark_node;
3381 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3382 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3384 /* [temp.arg.nontype]/1
3386 A template-argument for a non-type, non-template template-parameter
3389 -- the address of an object or function with external linkage. */
3390 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3392 error ("%qE is not a valid template argument for type %qT "
3393 "because function %qD has not external linkage",
3394 expr, type, fn_no_ptr);
3401 /* Attempt to convert the non-type template parameter EXPR to the
3402 indicated TYPE. If the conversion is successful, return the
3403 converted value. If the conversion is unsuccessful, return
3404 NULL_TREE if we issued an error message, or error_mark_node if we
3405 did not. We issue error messages for out-and-out bad template
3406 parameters, but not simply because the conversion failed, since we
3407 might be just trying to do argument deduction. Both TYPE and EXPR
3408 must be non-dependent.
3410 The conversion follows the special rules described in
3411 [temp.arg.nontype], and it is much more strict than an implicit
3414 This function is called twice for each template argument (see
3415 lookup_template_class for a more accurate description of this
3416 problem). This means that we need to handle expressions which
3417 are not valid in a C++ source, but can be created from the
3418 first call (for instance, casts to perform conversions). These
3419 hacks can go away after we fix the double coercion problem. */
3422 convert_nontype_argument (tree type, tree expr)
3426 /* Detect immediately string literals as invalid non-type argument.
3427 This special-case is not needed for correctness (we would easily
3428 catch this later), but only to provide better diagnostic for this
3429 common user mistake. As suggested by DR 100, we do not mention
3430 linkage issues in the diagnostic as this is not the point. */
3431 if (TREE_CODE (expr) == STRING_CST)
3433 error ("%qE is not a valid template argument for type %qT "
3434 "because string literals can never be used in this context",
3439 /* If we are in a template, EXPR may be non-dependent, but still
3440 have a syntactic, rather than semantic, form. For example, EXPR
3441 might be a SCOPE_REF, rather than the VAR_DECL to which the
3442 SCOPE_REF refers. Preserving the qualifying scope is necessary
3443 so that access checking can be performed when the template is
3444 instantiated -- but here we need the resolved form so that we can
3445 convert the argument. */
3446 expr = fold_non_dependent_expr (expr);
3447 expr_type = TREE_TYPE (expr);
3449 /* HACK: Due to double coercion, we can get a
3450 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3451 which is the tree that we built on the first call (see
3452 below when coercing to reference to object or to reference to
3453 function). We just strip everything and get to the arg.
3454 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3456 if (TREE_CODE (expr) == NOP_EXPR)
3458 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3460 /* ??? Maybe we could use convert_from_reference here, but we
3461 would need to relax its constraints because the NOP_EXPR
3462 could actually change the type to something more cv-qualified,
3463 and this is not folded by convert_from_reference. */
3464 tree addr = TREE_OPERAND (expr, 0);
3465 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3466 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3467 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3468 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3469 (TREE_TYPE (expr_type),
3470 TREE_TYPE (TREE_TYPE (addr))));
3472 expr = TREE_OPERAND (addr, 0);
3473 expr_type = TREE_TYPE (expr);
3476 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3477 parameter is a pointer to object, through decay and
3478 qualification conversion. Let's strip everything. */
3479 else if (TYPE_PTROBV_P (type))
3482 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3483 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3484 /* Skip the ADDR_EXPR only if it is part of the decay for
3485 an array. Otherwise, it is part of the original argument
3486 in the source code. */
3487 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3488 expr = TREE_OPERAND (expr, 0);
3489 expr_type = TREE_TYPE (expr);
3493 /* [temp.arg.nontype]/5, bullet 1
3495 For a non-type template-parameter of integral or enumeration type,
3496 integral promotions (_conv.prom_) and integral conversions
3497 (_conv.integral_) are applied. */
3498 if (INTEGRAL_TYPE_P (type))
3500 if (!INTEGRAL_TYPE_P (expr_type))
3501 return error_mark_node;
3503 expr = fold_decl_constant_value (expr);
3504 /* Notice that there are constant expressions like '4 % 0' which
3505 do not fold into integer constants. */
3506 if (TREE_CODE (expr) != INTEGER_CST)
3508 error ("%qE is not a valid template argument for type %qT "
3509 "because it is a non-constant expression", expr, type);
3513 /* At this point, an implicit conversion does what we want,
3514 because we already know that the expression is of integral
3516 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3517 if (expr == error_mark_node)
3518 return error_mark_node;
3520 /* Conversion was allowed: fold it to a bare integer constant. */
3523 /* [temp.arg.nontype]/5, bullet 2
3525 For a non-type template-parameter of type pointer to object,
3526 qualification conversions (_conv.qual_) and the array-to-pointer
3527 conversion (_conv.array_) are applied. */
3528 else if (TYPE_PTROBV_P (type))
3530 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3532 A template-argument for a non-type, non-template template-parameter
3533 shall be one of: [...]
3535 -- the name of a non-type template-parameter;
3536 -- the address of an object or function with external linkage, [...]
3537 expressed as "& id-expression" where the & is optional if the name
3538 refers to a function or array, or if the corresponding
3539 template-parameter is a reference.
3541 Here, we do not care about functions, as they are invalid anyway
3542 for a parameter of type pointer-to-object. */
3543 bool constant_address_p =
3544 (TREE_CODE (expr) == ADDR_EXPR
3545 || TREE_CODE (expr_type) == ARRAY_TYPE
3546 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3548 expr = decay_conversion (expr);
3549 if (expr == error_mark_node)
3550 return error_mark_node;
3552 expr = perform_qualification_conversions (type, expr);
3553 if (expr == error_mark_node)
3554 return error_mark_node;
3556 if (!constant_address_p)
3558 error ("%qE is not a valid template argument for type %qT "
3559 "because it is not a constant pointer", expr, type);
3563 /* [temp.arg.nontype]/5, bullet 3
3565 For a non-type template-parameter of type reference to object, no
3566 conversions apply. The type referred to by the reference may be more
3567 cv-qualified than the (otherwise identical) type of the
3568 template-argument. The template-parameter is bound directly to the
3569 template-argument, which must be an lvalue. */
3570 else if (TYPE_REF_OBJ_P (type))
3572 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3574 return error_mark_node;
3576 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3578 error ("%qE is not a valid template argument for type %qT "
3579 "because of conflicts in cv-qualification", expr, type);
3583 if (!real_lvalue_p (expr))
3585 error ("%qE is not a valid template argument for type %qT "
3586 "because it is not a lvalue", expr, type);
3590 /* [temp.arg.nontype]/1
3592 A template-argument for a non-type, non-template template-parameter
3593 shall be one of: [...]
3595 -- the address of an object or function with external linkage. */
3596 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3598 error ("%qE is not a valid template argument for type %qT "
3599 "because object %qD has not external linkage",
3604 expr = build_nop (type, build_address (expr));
3606 /* [temp.arg.nontype]/5, bullet 4
3608 For a non-type template-parameter of type pointer to function, only
3609 the function-to-pointer conversion (_conv.func_) is applied. If the
3610 template-argument represents a set of overloaded functions (or a
3611 pointer to such), the matching function is selected from the set
3613 else if (TYPE_PTRFN_P (type))
3615 /* If the argument is a template-id, we might not have enough
3616 context information to decay the pointer.
3617 ??? Why static5.C requires decay and subst1.C works fine
3619 if (!type_unknown_p (expr_type))
3621 expr = decay_conversion (expr);
3622 if (expr == error_mark_node)
3623 return error_mark_node;
3626 expr = convert_nontype_argument_function (type, expr);
3627 if (!expr || expr == error_mark_node)
3630 /* [temp.arg.nontype]/5, bullet 5
3632 For a non-type template-parameter of type reference to function, no
3633 conversions apply. If the template-argument represents a set of
3634 overloaded functions, the matching function is selected from the set
3636 else if (TYPE_REFFN_P (type))
3638 if (TREE_CODE (expr) == ADDR_EXPR)
3640 error ("%qE is not a valid template argument for type %qT "
3641 "because it is a pointer", expr, type);
3642 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3646 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3647 if (!expr || expr == error_mark_node)
3650 expr = build_nop (type, build_address (expr));
3652 /* [temp.arg.nontype]/5, bullet 6
3654 For a non-type template-parameter of type pointer to member function,
3655 no conversions apply. If the template-argument represents a set of
3656 overloaded member functions, the matching member function is selected
3657 from the set (_over.over_). */
3658 else if (TYPE_PTRMEMFUNC_P (type))
3660 expr = instantiate_type (type, expr, tf_none);
3661 if (expr == error_mark_node)
3662 return error_mark_node;
3664 /* There is no way to disable standard conversions in
3665 resolve_address_of_overloaded_function (called by
3666 instantiate_type). It is possible that the call succeeded by
3667 converting &B::I to &D::I (where B is a base of D), so we need
3668 to reject this conversion here.
3670 Actually, even if there was a way to disable standard conversions,
3671 it would still be better to reject them here so that we can
3672 provide a superior diagnostic. */
3673 if (!same_type_p (TREE_TYPE (expr), type))
3675 /* Make sure we are just one standard conversion off. */
3676 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3677 error ("%qE is not a valid template argument for type %qT "
3678 "because it is of type %qT", expr, type,
3680 inform ("standard conversions are not allowed in this context");
3684 /* [temp.arg.nontype]/5, bullet 7
3686 For a non-type template-parameter of type pointer to data member,
3687 qualification conversions (_conv.qual_) are applied. */
3688 else if (TYPE_PTRMEM_P (type))
3690 expr = perform_qualification_conversions (type, expr);
3691 if (expr == error_mark_node)
3694 /* A template non-type parameter must be one of the above. */
3698 /* Sanity check: did we actually convert the argument to the
3700 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3705 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3706 template template parameters. Both PARM_PARMS and ARG_PARMS are
3707 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3710 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3711 the case, then extra parameters must have default arguments.
3713 Consider the example:
3714 template <class T, class Allocator = allocator> class vector;
3715 template<template <class U> class TT> class C;
3717 C<vector> is a valid instantiation. PARM_PARMS for the above code
3718 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3719 T and Allocator) and OUTER_ARGS contains the argument that is used to
3720 substitute the TT parameter. */
3723 coerce_template_template_parms (tree parm_parms,
3725 tsubst_flags_t complain,
3729 int nparms, nargs, i;
3732 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3733 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3735 nparms = TREE_VEC_LENGTH (parm_parms);
3736 nargs = TREE_VEC_LENGTH (arg_parms);
3738 /* The rule here is opposite of coerce_template_parms. */
3741 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3744 for (i = 0; i < nparms; ++i)
3746 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3747 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3749 if (arg == NULL_TREE || arg == error_mark_node
3750 || parm == NULL_TREE || parm == error_mark_node)
3753 if (TREE_CODE (arg) != TREE_CODE (parm))
3756 switch (TREE_CODE (parm))
3762 /* We encounter instantiations of templates like
3763 template <template <template <class> class> class TT>
3766 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3767 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3769 if (!coerce_template_template_parms
3770 (parmparm, argparm, complain, in_decl, outer_args))
3776 /* The tsubst call is used to handle cases such as
3778 template <int> class C {};
3779 template <class T, template <T> class TT> class D {};
3782 i.e. the parameter list of TT depends on earlier parameters. */
3783 if (!dependent_type_p (TREE_TYPE (arg))
3785 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3797 /* Convert the indicated template ARG as necessary to match the
3798 indicated template PARM. Returns the converted ARG, or
3799 error_mark_node if the conversion was unsuccessful. Error and
3800 warning messages are issued under control of COMPLAIN. This
3801 conversion is for the Ith parameter in the parameter list. ARGS is
3802 the full set of template arguments deduced so far. */
3805 convert_template_argument (tree parm,
3808 tsubst_flags_t complain,
3814 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3816 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3818 if (TREE_CODE (arg) == TREE_LIST
3819 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3821 /* The template argument was the name of some
3822 member function. That's usually
3823 invalid, but static members are OK. In any
3824 case, grab the underlying fields/functions
3825 and issue an error later if required. */
3826 arg = TREE_VALUE (arg);
3827 TREE_TYPE (arg) = unknown_type_node;
3830 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3831 requires_type = (TREE_CODE (parm) == TYPE_DECL
3832 || requires_tmpl_type);
3834 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3835 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3836 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3837 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3840 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3841 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3842 arg = TYPE_STUB_DECL (arg);
3844 is_type = TYPE_P (arg) || is_tmpl_type;
3846 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3847 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3849 pedwarn ("to refer to a type member of a template parameter, "
3850 "use %<typename %E%>", arg);
3852 arg = make_typename_type (TREE_OPERAND (arg, 0),
3853 TREE_OPERAND (arg, 1),
3855 complain & tf_error);
3858 if (is_type != requires_type)
3862 if (complain & tf_error)
3864 error ("type/value mismatch at argument %d in template "
3865 "parameter list for %qD",
3868 error (" expected a constant of type %qT, got %qT",
3870 (is_tmpl_type ? DECL_NAME (arg) : arg));
3871 else if (requires_tmpl_type)
3872 error (" expected a class template, got %qE", arg);
3874 error (" expected a type, got %qE", arg);
3877 return error_mark_node;
3879 if (is_tmpl_type ^ requires_tmpl_type)
3881 if (in_decl && (complain & tf_error))
3883 error ("type/value mismatch at argument %d in template "
3884 "parameter list for %qD",
3887 error (" expected a type, got %qT", DECL_NAME (arg));
3889 error (" expected a class template, got %qT", arg);
3891 return error_mark_node;
3896 if (requires_tmpl_type)
3898 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3899 /* The number of argument required is not known yet.
3900 Just accept it for now. */
3901 val = TREE_TYPE (arg);
3904 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3905 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3907 if (coerce_template_template_parms (parmparm, argparm,
3913 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3915 if (val != error_mark_node
3916 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3917 val = TREE_TYPE (val);
3921 if (in_decl && (complain & tf_error))
3923 error ("type/value mismatch at argument %d in "
3924 "template parameter list for %qD",
3926 error (" expected a template of type %qD, got %qD",
3930 val = error_mark_node;
3939 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3941 if (invalid_nontype_parm_type_p (t, complain))
3942 return error_mark_node;
3944 if (!uses_template_parms (arg) && !uses_template_parms (t))
3945 /* We used to call digest_init here. However, digest_init
3946 will report errors, which we don't want when complain
3947 is zero. More importantly, digest_init will try too
3948 hard to convert things: for example, `0' should not be
3949 converted to pointer type at this point according to
3950 the standard. Accepting this is not merely an
3951 extension, since deciding whether or not these
3952 conversions can occur is part of determining which
3953 function template to call, or whether a given explicit
3954 argument specification is valid. */
3955 val = convert_nontype_argument (t, arg);
3959 if (val == NULL_TREE)
3960 val = error_mark_node;
3961 else if (val == error_mark_node && (complain & tf_error))
3962 error ("could not convert template argument %qE to %qT", arg, t);
3968 /* Convert all template arguments to their appropriate types, and
3969 return a vector containing the innermost resulting template
3970 arguments. If any error occurs, return error_mark_node. Error and
3971 warning messages are issued under control of COMPLAIN.
3973 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3974 provided in ARGLIST, or else trailing parameters must have default
3975 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3976 deduction for any unspecified trailing arguments. */
3979 coerce_template_parms (tree parms,
3982 tsubst_flags_t complain,
3983 int require_all_arguments)
3985 int nparms, nargs, i, lost = 0;
3988 tree new_inner_args;
3990 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3991 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3992 nparms = TREE_VEC_LENGTH (parms);
3996 && require_all_arguments
3997 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3999 if (complain & tf_error)
4001 error ("wrong number of template arguments (%d, should be %d)",
4005 error ("provided for %q+D", in_decl);
4008 return error_mark_node;
4011 new_inner_args = make_tree_vec (nparms);
4012 new_args = add_outermost_template_args (args, new_inner_args);
4013 for (i = 0; i < nparms; i++)
4018 /* Get the Ith template parameter. */
4019 parm = TREE_VEC_ELT (parms, i);
4021 /* Calculate the Ith argument. */
4023 arg = TREE_VEC_ELT (inner_args, i);
4024 else if (require_all_arguments)
4025 /* There must be a default arg in this case. */
4026 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4032 if (arg == error_mark_node)
4034 if (complain & tf_error)
4035 error ("template argument %d is invalid", i + 1);
4038 arg = convert_template_argument (TREE_VALUE (parm),
4039 arg, new_args, complain, i,
4042 if (arg == error_mark_node)
4044 TREE_VEC_ELT (new_inner_args, i) = arg;
4048 return error_mark_node;
4050 return new_inner_args;
4053 /* Returns 1 if template args OT and NT are equivalent. */
4056 template_args_equal (tree ot, tree nt)
4061 if (TREE_CODE (nt) == TREE_VEC)
4062 /* For member templates */
4063 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4064 else if (TYPE_P (nt))
4065 return TYPE_P (ot) && same_type_p (ot, nt);
4066 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4069 return cp_tree_equal (ot, nt);
4072 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4073 of template arguments. Returns 0 otherwise. */
4076 comp_template_args (tree oldargs, tree newargs)
4080 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4083 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4085 tree nt = TREE_VEC_ELT (newargs, i);
4086 tree ot = TREE_VEC_ELT (oldargs, i);
4088 if (! template_args_equal (ot, nt))
4094 /* Given class template name and parameter list, produce a user-friendly name
4095 for the instantiation. */
4098 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4100 static struct obstack scratch_obstack;
4101 static char *scratch_firstobj;
4104 if (!scratch_firstobj)
4105 gcc_obstack_init (&scratch_obstack);
4107 obstack_free (&scratch_obstack, scratch_firstobj);
4108 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4110 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4111 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4115 nparms = TREE_VEC_LENGTH (parms);
4116 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4117 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4118 for (i = 0; i < nparms; i++)
4120 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4121 tree arg = TREE_VEC_ELT (arglist, i);
4126 if (TREE_CODE (parm) == TYPE_DECL)
4128 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4131 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4133 if (TREE_CODE (arg) == TEMPLATE_DECL)
4135 /* Already substituted with real template. Just output
4136 the template name here */
4137 tree context = DECL_CONTEXT (arg);
4140 /* The template may be defined in a namespace, or
4141 may be a member template. */
4142 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4143 || CLASS_TYPE_P (context));
4144 cat (decl_as_string (DECL_CONTEXT (arg),
4145 TFF_PLAIN_IDENTIFIER));
4148 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4151 /* Output the parameter declaration. */
4152 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4156 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4158 /* No need to check arglist against parmlist here; we did that
4159 in coerce_template_parms, called from lookup_template_class. */
4160 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4163 char *bufp = obstack_next_free (&scratch_obstack);
4165 while (bufp[offset - 1] == ' ')
4167 obstack_blank_fast (&scratch_obstack, offset);
4169 /* B<C<char> >, not B<C<char>> */
4170 if (bufp[offset - 1] == '>')
4175 return (char *) obstack_base (&scratch_obstack);
4179 classtype_mangled_name (tree t)
4181 if (CLASSTYPE_TEMPLATE_INFO (t)
4182 /* Specializations have already had their names set up in
4183 lookup_template_class. */
4184 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4186 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4188 /* For non-primary templates, the template parameters are
4189 implicit from their surrounding context. */
4190 if (PRIMARY_TEMPLATE_P (tmpl))
4192 tree name = DECL_NAME (tmpl);
4193 char *mangled_name = mangle_class_name_for_template
4194 (IDENTIFIER_POINTER (name),
4195 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4196 CLASSTYPE_TI_ARGS (t));
4197 tree id = get_identifier (mangled_name);
4198 IDENTIFIER_TEMPLATE (id) = name;
4203 return TYPE_IDENTIFIER (t);
4207 add_pending_template (tree d)
4209 tree ti = (TYPE_P (d)
4210 ? CLASSTYPE_TEMPLATE_INFO (d)
4211 : DECL_TEMPLATE_INFO (d));
4215 if (TI_PENDING_TEMPLATE_FLAG (ti))
4218 /* We are called both from instantiate_decl, where we've already had a
4219 tinst_level pushed, and instantiate_template, where we haven't.
4221 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4224 push_tinst_level (d);
4226 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4227 if (last_pending_template)
4228 TREE_CHAIN (last_pending_template) = pt;
4230 pending_templates = pt;
4232 last_pending_template = pt;
4234 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4241 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4242 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4243 documentation for TEMPLATE_ID_EXPR. */
4246 lookup_template_function (tree fns, tree arglist)
4250 if (fns == error_mark_node || arglist == error_mark_node)
4251 return error_mark_node;
4253 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4254 gcc_assert (fns && (is_overloaded_fn (fns)
4255 || TREE_CODE (fns) == IDENTIFIER_NODE));
4257 if (BASELINK_P (fns))
4259 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4261 BASELINK_FUNCTIONS (fns),
4266 type = TREE_TYPE (fns);
4267 if (TREE_CODE (fns) == OVERLOAD || !type)
4268 type = unknown_type_node;
4270 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4273 /* Within the scope of a template class S<T>, the name S gets bound
4274 (in build_self_reference) to a TYPE_DECL for the class, not a
4275 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4276 or one of its enclosing classes, and that type is a template,
4277 return the associated TEMPLATE_DECL. Otherwise, the original
4278 DECL is returned. */
4281 maybe_get_template_decl_from_type_decl (tree decl)
4283 return (decl != NULL_TREE
4284 && TREE_CODE (decl) == TYPE_DECL
4285 && DECL_ARTIFICIAL (decl)
4286 && CLASS_TYPE_P (TREE_TYPE (decl))
4287 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4288 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4291 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4292 parameters, find the desired type.
4294 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4296 IN_DECL, if non-NULL, is the template declaration we are trying to
4299 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4300 the class we are looking up.
4302 Issue error and warning messages under control of COMPLAIN.
4304 If the template class is really a local class in a template
4305 function, then the FUNCTION_CONTEXT is the function in which it is
4308 ??? Note that this function is currently called *twice* for each
4309 template-id: the first time from the parser, while creating the
4310 incomplete type (finish_template_type), and the second type during the
4311 real instantiation (instantiate_template_class). This is surely something
4312 that we want to avoid. It also causes some problems with argument
4313 coercion (see convert_nontype_argument for more information on this). */
4316 lookup_template_class (tree d1,
4321 tsubst_flags_t complain)
4323 tree template = NULL_TREE, parmlist;
4326 timevar_push (TV_NAME_LOOKUP);
4328 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4330 tree value = innermost_non_namespace_value (d1);
4331 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4336 push_decl_namespace (context);
4337 template = lookup_name (d1, /*prefer_type=*/0);
4338 template = maybe_get_template_decl_from_type_decl (template);
4340 pop_decl_namespace ();
4343 context = DECL_CONTEXT (template);
4345 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4347 tree type = TREE_TYPE (d1);
4349 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4350 an implicit typename for the second A. Deal with it. */
4351 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4352 type = TREE_TYPE (type);
4354 if (CLASSTYPE_TEMPLATE_INFO (type))
4356 template = CLASSTYPE_TI_TEMPLATE (type);
4357 d1 = DECL_NAME (template);
4360 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4361 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4363 template = TYPE_TI_TEMPLATE (d1);
4364 d1 = DECL_NAME (template);
4366 else if (TREE_CODE (d1) == TEMPLATE_DECL
4367 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4370 d1 = DECL_NAME (template);
4371 context = DECL_CONTEXT (template);
4374 /* Issue an error message if we didn't find a template. */
4377 if (complain & tf_error)
4378 error ("%qT is not a template", d1);
4379 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4382 if (TREE_CODE (template) != TEMPLATE_DECL
4383 /* Make sure it's a user visible template, if it was named by
4385 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4386 && !PRIMARY_TEMPLATE_P (template)))
4388 if (complain & tf_error)
4390 error ("non-template type %qT used as a template", d1);
4392 error ("for template declaration %q+D", in_decl);
4394 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4397 complain &= ~tf_user;
4399 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4401 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4402 template arguments */
4407 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4409 /* Consider an example where a template template parameter declared as
4411 template <class T, class U = std::allocator<T> > class TT
4413 The template parameter level of T and U are one level larger than
4414 of TT. To proper process the default argument of U, say when an
4415 instantiation `TT<int>' is seen, we need to build the full
4416 arguments containing {int} as the innermost level. Outer levels,
4417 available when not appearing as default template argument, can be
4418 obtained from `current_template_args ()'.
4420 Suppose that TT is later substituted with std::vector. The above
4421 instantiation is `TT<int, std::allocator<T> >' with TT at
4422 level 1, and T at level 2, while the template arguments at level 1
4423 becomes {std::vector} and the inner level 2 is {int}. */
4425 if (current_template_parms)
4426 arglist = add_to_template_args (current_template_args (), arglist);
4428 arglist2 = coerce_template_parms (parmlist, arglist, template,
4429 complain, /*require_all_args=*/1);
4430 if (arglist2 == error_mark_node
4431 || (!uses_template_parms (arglist2)
4432 && check_instantiated_args (template, arglist2, complain)))
4433 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4435 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4436 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4440 tree template_type = TREE_TYPE (template);
4443 tree found = NULL_TREE;
4446 int is_partial_instantiation;
4448 gen_tmpl = most_general_template (template);
4449 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4450 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4451 arg_depth = TMPL_ARGS_DEPTH (arglist);
4453 if (arg_depth == 1 && parm_depth > 1)
4455 /* We've been given an incomplete set of template arguments.
4458 template <class T> struct S1 {
4459 template <class U> struct S2 {};
4460 template <class U> struct S2<U*> {};
4463 we will be called with an ARGLIST of `U*', but the
4464 TEMPLATE will be `template <class T> template
4465 <class U> struct S1<T>::S2'. We must fill in the missing
4468 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4470 arg_depth = TMPL_ARGS_DEPTH (arglist);
4473 /* Now we should have enough arguments. */
4474 gcc_assert (parm_depth == arg_depth);
4476 /* From here on, we're only interested in the most general
4478 template = gen_tmpl;
4480 /* Calculate the BOUND_ARGS. These will be the args that are
4481 actually tsubst'd into the definition to create the
4485 /* We have multiple levels of arguments to coerce, at once. */
4487 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4489 tree bound_args = make_tree_vec (parm_depth);
4491 for (i = saved_depth,
4492 t = DECL_TEMPLATE_PARMS (template);
4493 i > 0 && t != NULL_TREE;
4494 --i, t = TREE_CHAIN (t))
4496 tree a = coerce_template_parms (TREE_VALUE (t),
4498 complain, /*require_all_args=*/1);
4500 /* Don't process further if one of the levels fails. */
4501 if (a == error_mark_node)
4503 /* Restore the ARGLIST to its full size. */
4504 TREE_VEC_LENGTH (arglist) = saved_depth;
4505 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4508 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4510 /* We temporarily reduce the length of the ARGLIST so
4511 that coerce_template_parms will see only the arguments
4512 corresponding to the template parameters it is
4514 TREE_VEC_LENGTH (arglist)--;
4517 /* Restore the ARGLIST to its full size. */
4518 TREE_VEC_LENGTH (arglist) = saved_depth;
4520 arglist = bound_args;
4524 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4525 INNERMOST_TEMPLATE_ARGS (arglist),
4527 complain, /*require_all_args=*/1);
4529 if (arglist == error_mark_node)
4530 /* We were unable to bind the arguments. */
4531 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4533 /* In the scope of a template class, explicit references to the
4534 template class refer to the type of the template, not any
4535 instantiation of it. For example, in:
4537 template <class T> class C { void f(C<T>); }
4539 the `C<T>' is just the same as `C'. Outside of the
4540 class, however, such a reference is an instantiation. */
4541 if (comp_template_args (TYPE_TI_ARGS (template_type),
4544 found = template_type;
4546 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4550 for (ctx = current_class_type;
4551 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4553 ? TYPE_CONTEXT (ctx)
4554 : DECL_CONTEXT (ctx)))
4555 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4558 /* We're not in the scope of the class, so the
4559 TEMPLATE_TYPE is not the type we want after all. */
4565 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4567 /* If we already have this specialization, return it. */
4568 found = retrieve_specialization (template, arglist,
4569 /*class_specializations_p=*/false);
4571 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4573 /* This type is a "partial instantiation" if any of the template
4574 arguments still involve template parameters. Note that we set
4575 IS_PARTIAL_INSTANTIATION for partial specializations as
4577 is_partial_instantiation = uses_template_parms (arglist);
4579 /* If the deduced arguments are invalid, then the binding
4581 if (!is_partial_instantiation
4582 && check_instantiated_args (template,
4583 INNERMOST_TEMPLATE_ARGS (arglist),
4585 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4587 if (!is_partial_instantiation
4588 && !PRIMARY_TEMPLATE_P (template)
4589 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4591 found = xref_tag_from_type (TREE_TYPE (template),
4592 DECL_NAME (template),
4593 /*tag_scope=*/ts_global);
4594 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4597 context = tsubst (DECL_CONTEXT (template), arglist,
4600 context = global_namespace;
4602 /* Create the type. */
4603 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4605 if (!is_partial_instantiation)
4607 set_current_access_from_decl (TYPE_NAME (template_type));
4608 t = start_enum (TYPE_IDENTIFIER (template_type));
4611 /* We don't want to call start_enum for this type, since
4612 the values for the enumeration constants may involve
4613 template parameters. And, no one should be interested
4614 in the enumeration constants for such a type. */
4615 t = make_node (ENUMERAL_TYPE);
4619 t = make_aggr_type (TREE_CODE (template_type));
4620 CLASSTYPE_DECLARED_CLASS (t)
4621 = CLASSTYPE_DECLARED_CLASS (template_type);
4622 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4623 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4625 /* A local class. Make sure the decl gets registered properly. */
4626 if (context == current_function_decl)
4627 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
4630 /* If we called start_enum or pushtag above, this information
4631 will already be set up. */
4634 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4636 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4637 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4638 TYPE_STUB_DECL (t) = type_decl;
4639 DECL_SOURCE_LOCATION (type_decl)
4640 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4643 type_decl = TYPE_NAME (t);
4645 TREE_PRIVATE (type_decl)
4646 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4647 TREE_PROTECTED (type_decl)
4648 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4649 DECL_IN_SYSTEM_HEADER (type_decl)
4650 = DECL_IN_SYSTEM_HEADER (template);
4651 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
4653 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
4654 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
4657 /* Set up the template information. We have to figure out which
4658 template is the immediate parent if this is a full
4660 if (parm_depth == 1 || is_partial_instantiation
4661 || !PRIMARY_TEMPLATE_P (template))
4662 /* This case is easy; there are no member templates involved. */
4666 /* This is a full instantiation of a member template. Look
4667 for a partial instantiation of which this is an instance. */
4669 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4670 found; found = TREE_CHAIN (found))
4673 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4675 /* We only want partial instantiations, here, not
4676 specializations or full instantiations. */
4677 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4678 || !uses_template_parms (TREE_VALUE (found)))
4681 /* Temporarily reduce by one the number of levels in the
4682 ARGLIST and in FOUND so as to avoid comparing the
4683 last set of arguments. */
4684 TREE_VEC_LENGTH (arglist)--;
4685 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4687 /* See if the arguments match. If they do, then TMPL is
4688 the partial instantiation we want. */
4689 success = comp_template_args (TREE_PURPOSE (found), arglist);
4691 /* Restore the argument vectors to their full size. */
4692 TREE_VEC_LENGTH (arglist)++;
4693 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4704 /* There was no partial instantiation. This happens
4705 where C<T> is a member template of A<T> and it's used
4708 template <typename T> struct B { A<T>::C<int> m; };
4711 Create the partial instantiation.
4713 TREE_VEC_LENGTH (arglist)--;
4714 found = tsubst (template, arglist, complain, NULL_TREE);
4715 TREE_VEC_LENGTH (arglist)++;
4719 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4720 DECL_TEMPLATE_INSTANTIATIONS (template)
4721 = tree_cons (arglist, t,
4722 DECL_TEMPLATE_INSTANTIATIONS (template));
4724 if (TREE_CODE (t) == ENUMERAL_TYPE
4725 && !is_partial_instantiation)
4726 /* Now that the type has been registered on the instantiations
4727 list, we set up the enumerators. Because the enumeration
4728 constants may involve the enumeration type itself, we make
4729 sure to register the type first, and then create the
4730 constants. That way, doing tsubst_expr for the enumeration
4731 constants won't result in recursive calls here; we'll find
4732 the instantiation and exit above. */
4733 tsubst_enum (template_type, t, arglist);
4735 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4737 if (TREE_CODE (t) != ENUMERAL_TYPE)
4738 DECL_NAME (type_decl) = classtype_mangled_name (t);
4739 if (is_partial_instantiation)
4740 /* If the type makes use of template parameters, the
4741 code that generates debugging information will crash. */
4742 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4744 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4746 timevar_pop (TV_NAME_LOOKUP);
4753 struct pointer_set_t *visited;
4756 /* Called from for_each_template_parm via walk_tree. */
4759 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4762 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4763 tree_fn_t fn = pfd->fn;
4764 void *data = pfd->data;
4767 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4768 return error_mark_node;
4770 switch (TREE_CODE (t))
4773 if (TYPE_PTRMEMFUNC_P (t))
4779 if (!TYPE_TEMPLATE_INFO (t))
4781 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4782 fn, data, pfd->visited))
4783 return error_mark_node;
4787 /* Since we're not going to walk subtrees, we have to do this
4789 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4791 return error_mark_node;
4795 /* Check the return type. */
4796 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4797 return error_mark_node;
4799 /* Check the parameter types. Since default arguments are not
4800 instantiated until they are needed, the TYPE_ARG_TYPES may
4801 contain expressions that involve template parameters. But,
4802 no-one should be looking at them yet. And, once they're
4803 instantiated, they don't contain template parameters, so
4804 there's no point in looking at them then, either. */
4808 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4809 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4811 return error_mark_node;
4813 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4814 want walk_tree walking into them itself. */
4820 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4822 return error_mark_node;
4827 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4828 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4830 return error_mark_node;
4835 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4836 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4838 return error_mark_node;
4839 if (DECL_CONTEXT (t)
4840 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4842 return error_mark_node;
4845 case BOUND_TEMPLATE_TEMPLATE_PARM:
4846 /* Record template parameters such as `T' inside `TT<T>'. */
4847 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4848 return error_mark_node;
4851 case TEMPLATE_TEMPLATE_PARM:
4852 case TEMPLATE_TYPE_PARM:
4853 case TEMPLATE_PARM_INDEX:
4854 if (fn && (*fn)(t, data))
4855 return error_mark_node;
4857 return error_mark_node;
4861 /* A template template parameter is encountered. */
4862 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4863 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4864 return error_mark_node;
4866 /* Already substituted template template parameter */
4872 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4873 data, pfd->visited))
4874 return error_mark_node;
4878 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4879 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4880 (TREE_TYPE (t)), fn, data,
4882 return error_mark_node;
4887 /* If there's no type, then this thing must be some expression
4888 involving template parameters. */
4889 if (!fn && !TREE_TYPE (t))
4890 return error_mark_node;
4895 case REINTERPRET_CAST_EXPR:
4896 case CONST_CAST_EXPR:
4897 case STATIC_CAST_EXPR:
4898 case DYNAMIC_CAST_EXPR:
4902 case PSEUDO_DTOR_EXPR:
4904 return error_mark_node;
4908 /* If we do not handle this case specially, we end up walking
4909 the BINFO hierarchy, which is circular, and therefore
4910 confuses walk_tree. */
4912 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4914 return error_mark_node;
4921 /* We didn't find any template parameters we liked. */
4925 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4926 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4927 call FN with the parameter and the DATA.
4928 If FN returns nonzero, the iteration is terminated, and
4929 for_each_template_parm returns 1. Otherwise, the iteration
4930 continues. If FN never returns a nonzero value, the value
4931 returned by for_each_template_parm is 0. If FN is NULL, it is
4932 considered to be the function which always returns 1. */
4935 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4936 struct pointer_set_t *visited)
4938 struct pair_fn_data pfd;
4945 /* Walk the tree. (Conceptually, we would like to walk without
4946 duplicates, but for_each_template_parm_r recursively calls
4947 for_each_template_parm, so we would need to reorganize a fair
4948 bit to use walk_tree_without_duplicates, so we keep our own
4951 pfd.visited = visited;
4953 pfd.visited = pointer_set_create ();
4954 result = walk_tree (&t,
4955 for_each_template_parm_r,
4957 pfd.visited) != NULL_TREE;
4962 pointer_set_destroy (pfd.visited);
4969 /* Returns true if T depends on any template parameter. */
4972 uses_template_parms (tree t)
4975 int saved_processing_template_decl;
4977 saved_processing_template_decl = processing_template_decl;
4978 if (!saved_processing_template_decl)
4979 processing_template_decl = 1;
4981 dependent_p = dependent_type_p (t);
4982 else if (TREE_CODE (t) == TREE_VEC)
4983 dependent_p = any_dependent_template_arguments_p (t);
4984 else if (TREE_CODE (t) == TREE_LIST)
4985 dependent_p = (uses_template_parms (TREE_VALUE (t))
4986 || uses_template_parms (TREE_CHAIN (t)));
4989 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4990 || TREE_CODE (t) == OVERLOAD
4991 || TREE_CODE (t) == BASELINK
4992 || TREE_CODE (t) == IDENTIFIER_NODE
4993 || CONSTANT_CLASS_P (t))
4994 dependent_p = (type_dependent_expression_p (t)
4995 || value_dependent_expression_p (t));
4998 gcc_assert (t == error_mark_node);
4999 dependent_p = false;
5002 processing_template_decl = saved_processing_template_decl;
5007 /* Returns true if T depends on any template parameter with level LEVEL. */
5010 uses_template_parms_level (tree t, int level)
5012 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
5015 static int tinst_depth;
5016 extern int max_tinst_depth;
5017 #ifdef GATHER_STATISTICS
5020 static int tinst_level_tick;
5021 static int last_template_error_tick;
5023 /* We're starting to instantiate D; record the template instantiation context
5024 for diagnostics and to restore it later. */
5027 push_tinst_level (tree d)
5031 if (tinst_depth >= max_tinst_depth)
5033 /* If the instantiation in question still has unbound template parms,
5034 we don't really care if we can't instantiate it, so just return.
5035 This happens with base instantiation for implicit `typename'. */
5036 if (uses_template_parms (d))
5039 last_template_error_tick = tinst_level_tick;
5040 error ("template instantiation depth exceeds maximum of %d (use "
5041 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5042 max_tinst_depth, d);
5044 print_instantiation_context ();
5049 new = make_node (TINST_LEVEL);
5050 TINST_DECL (new) = d;
5051 TINST_LOCATION (new) = input_location;
5052 TINST_IN_SYSTEM_HEADER_P (new) = in_system_header;
5053 TREE_CHAIN (new) = current_tinst_level;
5054 current_tinst_level = new;
5057 #ifdef GATHER_STATISTICS
5058 if (tinst_depth > depth_reached)
5059 depth_reached = tinst_depth;
5066 /* We're done instantiating this template; return to the instantiation
5070 pop_tinst_level (void)
5072 tree old = current_tinst_level;
5074 /* Restore the filename and line number stashed away when we started
5075 this instantiation. */
5076 input_location = TINST_LOCATION (old);
5077 in_system_header = TINST_IN_SYSTEM_HEADER_P (old);
5078 current_tinst_level = TREE_CHAIN (old);
5083 /* We're instantiating a deferred template; restore the template
5084 instantiation context in which the instantiation was requested, which
5085 is one step out from LEVEL. */
5088 reopen_tinst_level (tree level)
5093 for (t = level; t; t = TREE_CHAIN (t))
5096 current_tinst_level = level;
5100 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5101 vector of template arguments, as for tsubst.
5103 Returns an appropriate tsubst'd friend declaration. */
5106 tsubst_friend_function (tree decl, tree args)
5110 if (TREE_CODE (decl) == FUNCTION_DECL
5111 && DECL_TEMPLATE_INSTANTIATION (decl)
5112 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5113 /* This was a friend declared with an explicit template
5114 argument list, e.g.:
5118 to indicate that f was a template instantiation, not a new
5119 function declaration. Now, we have to figure out what
5120 instantiation of what template. */
5122 tree template_id, arglist, fns;
5125 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5127 /* Friend functions are looked up in the containing namespace scope.
5128 We must enter that scope, to avoid finding member functions of the
5129 current cless with same name. */
5130 push_nested_namespace (ns);
5131 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5132 tf_error | tf_warning, NULL_TREE);
5133 pop_nested_namespace (ns);
5134 arglist = tsubst (DECL_TI_ARGS (decl), args,
5135 tf_error | tf_warning, NULL_TREE);
5136 template_id = lookup_template_function (fns, arglist);
5138 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5139 tmpl = determine_specialization (template_id, new_friend,
5141 /*need_member_template=*/0,
5142 TREE_VEC_LENGTH (args));
5143 return instantiate_template (tmpl, new_args, tf_error);
5146 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5148 /* The NEW_FRIEND will look like an instantiation, to the
5149 compiler, but is not an instantiation from the point of view of
5150 the language. For example, we might have had:
5152 template <class T> struct S {
5153 template <class U> friend void f(T, U);
5156 Then, in S<int>, template <class U> void f(int, U) is not an
5157 instantiation of anything. */
5158 if (new_friend == error_mark_node)
5159 return error_mark_node;
5161 DECL_USE_TEMPLATE (new_friend) = 0;
5162 if (TREE_CODE (decl) == TEMPLATE_DECL)
5164 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5165 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5166 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5169 /* The mangled name for the NEW_FRIEND is incorrect. The function
5170 is not a template instantiation and should not be mangled like
5171 one. Therefore, we forget the mangling here; we'll recompute it
5172 later if we need it. */
5173 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5175 SET_DECL_RTL (new_friend, NULL_RTX);
5176 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5179 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5182 tree new_friend_template_info;
5183 tree new_friend_result_template_info;
5185 int new_friend_is_defn;
5187 /* We must save some information from NEW_FRIEND before calling
5188 duplicate decls since that function will free NEW_FRIEND if
5190 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5191 new_friend_is_defn =
5192 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5193 (template_for_substitution (new_friend)))
5195 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5197 /* This declaration is a `primary' template. */
5198 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5200 new_friend_result_template_info
5201 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5204 new_friend_result_template_info = NULL_TREE;
5206 /* Inside pushdecl_namespace_level, we will push into the
5207 current namespace. However, the friend function should go
5208 into the namespace of the template. */
5209 ns = decl_namespace_context (new_friend);
5210 push_nested_namespace (ns);
5211 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
5212 pop_nested_namespace (ns);
5214 if (old_decl != new_friend)
5216 /* This new friend declaration matched an existing
5217 declaration. For example, given:
5219 template <class T> void f(T);
5220 template <class U> class C {
5221 template <class T> friend void f(T) {}
5224 the friend declaration actually provides the definition
5225 of `f', once C has been instantiated for some type. So,
5226 old_decl will be the out-of-class template declaration,
5227 while new_friend is the in-class definition.
5229 But, if `f' was called before this point, the
5230 instantiation of `f' will have DECL_TI_ARGS corresponding
5231 to `T' but not to `U', references to which might appear
5232 in the definition of `f'. Previously, the most general
5233 template for an instantiation of `f' was the out-of-class
5234 version; now it is the in-class version. Therefore, we
5235 run through all specialization of `f', adding to their
5236 DECL_TI_ARGS appropriately. In particular, they need a
5237 new set of outer arguments, corresponding to the
5238 arguments for this class instantiation.
5240 The same situation can arise with something like this:
5243 template <class T> class C {
5247 when `C<int>' is instantiated. Now, `f(int)' is defined
5250 if (!new_friend_is_defn)
5251 /* On the other hand, if the in-class declaration does
5252 *not* provide a definition, then we don't want to alter
5253 existing definitions. We can just leave everything
5258 /* Overwrite whatever template info was there before, if
5259 any, with the new template information pertaining to
5261 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5263 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5264 reregister_specialization (new_friend,
5265 most_general_template (old_decl),
5270 tree new_friend_args;
5272 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5273 = new_friend_result_template_info;
5275 new_friend_args = TI_ARGS (new_friend_template_info);
5276 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5280 tree spec = TREE_VALUE (t);
5283 = add_outermost_template_args (new_friend_args,
5284 DECL_TI_ARGS (spec));
5287 /* Now, since specializations are always supposed to
5288 hang off of the most general template, we must move
5290 t = most_general_template (old_decl);
5293 DECL_TEMPLATE_SPECIALIZATIONS (t)
5294 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5295 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5296 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5301 /* The information from NEW_FRIEND has been merged into OLD_DECL
5302 by duplicate_decls. */
5303 new_friend = old_decl;
5308 tree context = DECL_CONTEXT (new_friend);
5312 template <class T> class C {
5313 template <class U> friend void C1<U>::f (); // case 1
5314 friend void C2<T>::f (); // case 2
5316 we only need to make sure CONTEXT is a complete type for
5317 case 2. To distinguish between the two cases, we note that
5318 CONTEXT of case 1 remains dependent type after tsubst while
5319 this isn't true for case 2. */
5320 ++processing_template_decl;
5321 dependent_p = dependent_type_p (context);
5322 --processing_template_decl;
5325 && !complete_type_or_else (context, NULL_TREE))
5326 return error_mark_node;
5328 if (COMPLETE_TYPE_P (context))
5330 /* Check to see that the declaration is really present, and,
5331 possibly obtain an improved declaration. */
5332 tree fn = check_classfn (context,
5333 new_friend, NULL_TREE);
5343 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5344 template arguments, as for tsubst.
5346 Returns an appropriate tsubst'd friend type or error_mark_node on
5350 tsubst_friend_class (tree friend_tmpl, tree args)
5356 context = DECL_CONTEXT (friend_tmpl);
5360 if (TREE_CODE (context) == NAMESPACE_DECL)
5361 push_nested_namespace (context);
5363 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5366 /* First, we look for a class template. */
5367 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5369 /* But, if we don't find one, it might be because we're in a
5370 situation like this:
5378 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5379 for `S<int>', not the TEMPLATE_DECL. */
5380 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5382 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5383 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5386 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5388 /* The friend template has already been declared. Just
5389 check to see that the declarations match, and install any new
5390 default parameters. We must tsubst the default parameters,
5391 of course. We only need the innermost template parameters
5392 because that is all that redeclare_class_template will look
5394 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5395 > TMPL_ARGS_DEPTH (args))
5398 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5399 args, tf_error | tf_warning);
5400 redeclare_class_template (TREE_TYPE (tmpl), parms);
5403 friend_type = TREE_TYPE (tmpl);
5407 /* The friend template has not already been declared. In this
5408 case, the instantiation of the template class will cause the
5409 injection of this template into the global scope. */
5410 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5412 /* The new TMPL is not an instantiation of anything, so we
5413 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5414 the new type because that is supposed to be the corresponding
5415 template decl, i.e., TMPL. */
5416 DECL_USE_TEMPLATE (tmpl) = 0;
5417 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5418 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5419 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5420 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5422 /* Inject this template into the global scope. */
5423 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
5428 if (TREE_CODE (context) == NAMESPACE_DECL)
5429 pop_nested_namespace (context);
5431 pop_nested_class ();
5437 /* Returns zero if TYPE cannot be completed later due to circularity.
5438 Otherwise returns one. */
5441 can_complete_type_without_circularity (tree type)
5443 if (type == NULL_TREE || type == error_mark_node)
5445 else if (COMPLETE_TYPE_P (type))
5447 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5448 return can_complete_type_without_circularity (TREE_TYPE (type));
5449 else if (CLASS_TYPE_P (type)
5450 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5457 instantiate_class_template (tree type)
5459 tree template, args, pattern, t, member;
5464 if (type == error_mark_node)
5465 return error_mark_node;
5467 if (TYPE_BEING_DEFINED (type)
5468 || COMPLETE_TYPE_P (type)
5469 || dependent_type_p (type))
5472 /* Figure out which template is being instantiated. */
5473 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5474 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5476 /* Figure out which arguments are being used to do the
5478 args = CLASSTYPE_TI_ARGS (type);
5480 /* Determine what specialization of the original template to
5482 t = most_specialized_class (template, args);
5483 if (t == error_mark_node)
5485 const char *str = "candidates are:";
5486 error ("ambiguous class template instantiation for %q#T", type);
5487 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5490 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5492 error ("%s %+#T", str, TREE_TYPE (t));
5496 TYPE_BEING_DEFINED (type) = 1;
5497 return error_mark_node;
5501 pattern = TREE_TYPE (t);
5503 pattern = TREE_TYPE (template);
5505 /* If the template we're instantiating is incomplete, then clearly
5506 there's nothing we can do. */
5507 if (!COMPLETE_TYPE_P (pattern))
5510 /* If we've recursively instantiated too many templates, stop. */
5511 if (! push_tinst_level (type))
5514 /* Now we're really doing the instantiation. Mark the type as in
5515 the process of being defined. */
5516 TYPE_BEING_DEFINED (type) = 1;
5518 /* We may be in the middle of deferred access check. Disable
5520 push_deferring_access_checks (dk_no_deferred);
5522 push_to_top_level ();
5526 /* This TYPE is actually an instantiation of a partial
5527 specialization. We replace the innermost set of ARGS with
5528 the arguments appropriate for substitution. For example,
5531 template <class T> struct S {};
5532 template <class T> struct S<T*> {};
5534 and supposing that we are instantiating S<int*>, ARGS will
5535 present be {int*} but we need {int}. */
5537 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5540 /* If there were multiple levels in ARGS, replacing the
5541 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5542 want, so we make a copy first. */
5543 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5545 args = copy_node (args);
5546 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5552 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5554 /* Set the input location to the template definition. This is needed
5555 if tsubsting causes an error. */
5556 typedecl = TYPE_MAIN_DECL (type);
5557 input_location = DECL_SOURCE_LOCATION (typedecl);
5558 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
5560 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5561 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5562 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5563 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5564 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5565 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5566 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5567 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5568 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5569 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5570 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5571 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5572 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5573 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5574 if (ANON_AGGR_TYPE_P (pattern))
5575 SET_ANON_AGGR_TYPE_P (type);
5576 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
5578 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
5579 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
5582 pbinfo = TYPE_BINFO (pattern);
5584 /* We should never instantiate a nested class before its enclosing
5585 class; we need to look up the nested class by name before we can
5586 instantiate it, and that lookup should instantiate the enclosing
5588 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5589 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5590 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5592 base_list = NULL_TREE;
5593 if (BINFO_N_BASE_BINFOS (pbinfo))
5596 tree context = TYPE_CONTEXT (type);
5600 /* We must enter the scope containing the type, as that is where
5601 the accessibility of types named in dependent bases are
5603 pushed_scope = push_scope (context ? context : global_namespace);
5605 /* Substitute into each of the bases to determine the actual
5607 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5610 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5612 /* Substitute to figure out the base class. */
5613 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5614 if (base == error_mark_node)
5617 base_list = tree_cons (access, base, base_list);
5618 if (BINFO_VIRTUAL_P (pbase_binfo))
5619 TREE_TYPE (base_list) = integer_type_node;
5622 /* The list is now in reverse order; correct that. */
5623 base_list = nreverse (base_list);
5626 pop_scope (pushed_scope);
5628 /* Now call xref_basetypes to set up all the base-class
5630 xref_basetypes (type, base_list);
5633 /* Now that our base classes are set up, enter the scope of the
5634 class, so that name lookups into base classes, etc. will work
5635 correctly. This is precisely analogous to what we do in
5636 begin_class_definition when defining an ordinary non-template
5640 /* Now members are processed in the order of declaration. */
5641 for (member = CLASSTYPE_DECL_LIST (pattern);
5642 member; member = TREE_CHAIN (member))
5644 tree t = TREE_VALUE (member);
5646 if (TREE_PURPOSE (member))
5650 /* Build new CLASSTYPE_NESTED_UTDS. */
5653 tree name = TYPE_IDENTIFIER (tag);
5655 bool class_template_p;
5657 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5658 && TYPE_LANG_SPECIFIC (tag)
5659 && CLASSTYPE_IS_TEMPLATE (tag));
5660 /* If the member is a class template, then -- even after
5661 substitution -- there may be dependent types in the
5662 template argument list for the class. We increment
5663 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5664 that function will assume that no types are dependent
5665 when outside of a template. */
5666 if (class_template_p)
5667 ++processing_template_decl;
5668 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5669 if (class_template_p)
5670 --processing_template_decl;
5671 if (newtag == error_mark_node)
5674 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5676 if (class_template_p)
5677 /* Unfortunately, lookup_template_class sets
5678 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5679 instantiation (i.e., for the type of a member
5680 template class nested within a template class.)
5681 This behavior is required for
5682 maybe_process_partial_specialization to work
5683 correctly, but is not accurate in this case;
5684 the TAG is not an instantiation of anything.
5685 (The corresponding TEMPLATE_DECL is an
5686 instantiation, but the TYPE is not.) */
5687 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5689 /* Now, we call pushtag to put this NEWTAG into the scope of
5690 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5691 pushtag calling push_template_decl. We don't have to do
5692 this for enums because it will already have been done in
5695 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5696 pushtag (name, newtag, /*tag_scope=*/ts_current);
5699 else if (TREE_CODE (t) == FUNCTION_DECL
5700 || DECL_FUNCTION_TEMPLATE_P (t))
5702 /* Build new TYPE_METHODS. */
5705 if (TREE_CODE (t) == TEMPLATE_DECL)
5706 ++processing_template_decl;
5707 r = tsubst (t, args, tf_error, NULL_TREE);
5708 if (TREE_CODE (t) == TEMPLATE_DECL)
5709 --processing_template_decl;
5710 set_current_access_from_decl (r);
5711 grok_special_member_properties (r);
5712 finish_member_declaration (r);
5716 /* Build new TYPE_FIELDS. */
5718 if (TREE_CODE (t) != CONST_DECL)
5722 /* The the file and line for this declaration, to
5723 assist in error message reporting. Since we
5724 called push_tinst_level above, we don't need to
5726 input_location = DECL_SOURCE_LOCATION (t);
5728 if (TREE_CODE (t) == TEMPLATE_DECL)
5729 ++processing_template_decl;
5730 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5731 if (TREE_CODE (t) == TEMPLATE_DECL)
5732 --processing_template_decl;
5733 if (TREE_CODE (r) == VAR_DECL)
5737 [t]he initialization (and any associated
5738 side-effects) of a static data member does
5739 not occur unless the static data member is
5740 itself used in a way that requires the
5741 definition of the static data member to
5744 Therefore, we do not substitute into the
5745 initialized for the static data member here. */
5746 finish_static_data_member_decl
5749 /*asmspec_tree=*/NULL_TREE,
5751 if (DECL_INITIALIZED_IN_CLASS_P (r))
5752 check_static_variable_definition (r, TREE_TYPE (r));
5754 else if (TREE_CODE (r) == FIELD_DECL)
5756 /* Determine whether R has a valid type and can be
5757 completed later. If R is invalid, then it is
5758 replaced by error_mark_node so that it will not be
5759 added to TYPE_FIELDS. */
5760 tree rtype = TREE_TYPE (r);
5761 if (can_complete_type_without_circularity (rtype))
5762 complete_type (rtype);
5764 if (!COMPLETE_TYPE_P (rtype))
5766 cxx_incomplete_type_error (r, rtype);
5767 r = error_mark_node;
5771 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5772 such a thing will already have been added to the field
5773 list by tsubst_enum in finish_member_declaration in the
5774 CLASSTYPE_NESTED_UTDS case above. */
5775 if (!(TREE_CODE (r) == TYPE_DECL
5776 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5777 && DECL_ARTIFICIAL (r)))
5779 set_current_access_from_decl (r);
5780 finish_member_declaration (r);
5787 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5789 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5791 tree friend_type = t;
5792 bool adjust_processing_template_decl = false;
5794 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5796 /* template <class T> friend class C; */
5797 friend_type = tsubst_friend_class (friend_type, args);
5798 adjust_processing_template_decl = true;
5800 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5802 /* template <class T> friend class C::D; */
5803 friend_type = tsubst (friend_type, args,
5804 tf_error | tf_warning, NULL_TREE);
5805 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5806 friend_type = TREE_TYPE (friend_type);
5807 adjust_processing_template_decl = true;
5809 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5811 /* This could be either
5815 when dependent_type_p is false or
5817 template <class U> friend class T::C;
5820 friend_type = tsubst (friend_type, args,
5821 tf_error | tf_warning, NULL_TREE);
5822 /* Bump processing_template_decl for correct
5823 dependent_type_p calculation. */
5824 ++processing_template_decl;
5825 if (dependent_type_p (friend_type))
5826 adjust_processing_template_decl = true;
5827 --processing_template_decl;
5829 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
5830 && hidden_name_p (TYPE_NAME (friend_type)))
5834 where C hasn't been declared yet. Let's lookup name
5835 from namespace scope directly, bypassing any name that
5836 come from dependent base class. */
5837 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5839 /* The call to xref_tag_from_type does injection for friend
5841 push_nested_namespace (ns);
5843 xref_tag_from_type (friend_type, NULL_TREE,
5844 /*tag_scope=*/ts_current);
5845 pop_nested_namespace (ns);
5847 else if (uses_template_parms (friend_type))
5848 /* friend class C<T>; */
5849 friend_type = tsubst (friend_type, args,
5850 tf_error | tf_warning, NULL_TREE);
5855 where C is already declared or
5857 friend class C<int>;
5859 We don't have to do anything in these cases. */
5861 if (adjust_processing_template_decl)
5862 /* Trick make_friend_class into realizing that the friend
5863 we're adding is a template, not an ordinary class. It's
5864 important that we use make_friend_class since it will
5865 perform some error-checking and output cross-reference
5867 ++processing_template_decl;
5869 if (friend_type != error_mark_node)
5870 make_friend_class (type, friend_type, /*complain=*/false);
5872 if (adjust_processing_template_decl)
5873 --processing_template_decl;
5877 /* Build new DECL_FRIENDLIST. */
5880 /* The the file and line for this declaration, to
5881 assist in error message reporting. Since we
5882 called push_tinst_level above, we don't need to
5884 input_location = DECL_SOURCE_LOCATION (t);
5886 if (TREE_CODE (t) == TEMPLATE_DECL)
5888 ++processing_template_decl;
5889 push_deferring_access_checks (dk_no_check);
5892 r = tsubst_friend_function (t, args);
5893 add_friend (type, r, /*complain=*/false);
5894 if (TREE_CODE (t) == TEMPLATE_DECL)
5896 pop_deferring_access_checks ();
5897 --processing_template_decl;
5903 /* Set the file and line number information to whatever is given for
5904 the class itself. This puts error messages involving generated
5905 implicit functions at a predictable point, and the same point
5906 that would be used for non-template classes. */
5907 input_location = DECL_SOURCE_LOCATION (typedecl);
5909 unreverse_member_declarations (type);
5910 finish_struct_1 (type);
5911 TYPE_BEING_DEFINED (type) = 0;
5913 /* Now that the class is complete, instantiate default arguments for
5914 any member functions. We don't do this earlier because the
5915 default arguments may reference members of the class. */
5916 if (!PRIMARY_TEMPLATE_P (template))
5917 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5918 if (TREE_CODE (t) == FUNCTION_DECL
5919 /* Implicitly generated member functions will not have template
5920 information; they are not instantiations, but instead are
5921 created "fresh" for each instantiation. */
5922 && DECL_TEMPLATE_INFO (t))
5923 tsubst_default_arguments (t);
5926 pop_from_top_level ();
5927 pop_deferring_access_checks ();
5930 /* The vtable for a template class can be emitted in any translation
5931 unit in which the class is instantiated. When there is no key
5932 method, however, finish_struct_1 will already have added TYPE to
5933 the keyed_classes list. */
5934 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5935 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5941 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5947 else if (TYPE_P (t))
5948 r = tsubst (t, args, complain, in_decl);
5951 r = tsubst_expr (t, args, complain, in_decl);
5952 r = fold_non_dependent_expr (r);
5957 /* Substitute ARGS into the vector or list of template arguments T. */
5960 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5962 int len = TREE_VEC_LENGTH (t);
5963 int need_new = 0, i;
5964 tree *elts = alloca (len * sizeof (tree));
5966 for (i = 0; i < len; i++)
5968 tree orig_arg = TREE_VEC_ELT (t, i);
5971 if (TREE_CODE (orig_arg) == TREE_VEC)
5972 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5974 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5976 if (new_arg == error_mark_node)
5977 return error_mark_node;
5980 if (new_arg != orig_arg)
5987 t = make_tree_vec (len);
5988 for (i = 0; i < len; i++)
5989 TREE_VEC_ELT (t, i) = elts[i];
5994 /* Return the result of substituting ARGS into the template parameters
5995 given by PARMS. If there are m levels of ARGS and m + n levels of
5996 PARMS, then the result will contain n levels of PARMS. For
5997 example, if PARMS is `template <class T> template <class U>
5998 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5999 result will be `template <int*, double, class V>'. */
6002 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
6007 for (new_parms = &r;
6008 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
6009 new_parms = &(TREE_CHAIN (*new_parms)),
6010 parms = TREE_CHAIN (parms))
6013 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
6016 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
6018 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
6019 tree default_value = TREE_PURPOSE (tuple);
6020 tree parm_decl = TREE_VALUE (tuple);
6022 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
6023 if (TREE_CODE (parm_decl) == PARM_DECL
6024 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
6025 parm_decl = error_mark_node;
6026 default_value = tsubst_template_arg (default_value, args,
6027 complain, NULL_TREE);
6029 tuple = build_tree_list (default_value, parm_decl);
6030 TREE_VEC_ELT (new_vec, i) = tuple;
6034 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6035 - TMPL_ARGS_DEPTH (args)),
6036 new_vec, NULL_TREE);
6042 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6043 type T. If T is not an aggregate or enumeration type, it is
6044 handled as if by tsubst. IN_DECL is as for tsubst. If
6045 ENTERING_SCOPE is nonzero, T is the context for a template which
6046 we are presently tsubst'ing. Return the substituted value. */
6049 tsubst_aggr_type (tree t,
6051 tsubst_flags_t complain,
6058 switch (TREE_CODE (t))
6061 if (TYPE_PTRMEMFUNC_P (t))
6062 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6064 /* Else fall through. */
6067 if (TYPE_TEMPLATE_INFO (t))
6072 bool saved_skip_evaluation;
6074 /* In "sizeof(X<I>)" we need to evaluate "I". */
6075 saved_skip_evaluation = skip_evaluation;
6076 skip_evaluation = false;
6078 /* First, determine the context for the type we are looking
6080 context = TYPE_CONTEXT (t);
6082 context = tsubst_aggr_type (context, args, complain,
6083 in_decl, /*entering_scope=*/1);
6085 /* Then, figure out what arguments are appropriate for the
6086 type we are trying to find. For example, given:
6088 template <class T> struct S;
6089 template <class T, class U> void f(T, U) { S<U> su; }
6091 and supposing that we are instantiating f<int, double>,
6092 then our ARGS will be {int, double}, but, when looking up
6093 S we only want {double}. */
6094 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6096 if (argvec == error_mark_node)
6097 r = error_mark_node;
6100 r = lookup_template_class (t, argvec, in_decl, context,
6101 entering_scope, complain);
6102 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6105 skip_evaluation = saved_skip_evaluation;
6110 /* This is not a template type, so there's nothing to do. */
6114 return tsubst (t, args, complain, in_decl);
6118 /* Substitute into the default argument ARG (a default argument for
6119 FN), which has the indicated TYPE. */
6122 tsubst_default_argument (tree fn, tree type, tree arg)
6124 tree saved_class_ptr = NULL_TREE;
6125 tree saved_class_ref = NULL_TREE;
6127 /* This default argument came from a template. Instantiate the
6128 default argument here, not in tsubst. In the case of
6137 we must be careful to do name lookup in the scope of S<T>,
6138 rather than in the current class. */
6139 push_access_scope (fn);
6140 /* The "this" pointer is not valid in a default argument. */
6143 saved_class_ptr = current_class_ptr;
6144 cp_function_chain->x_current_class_ptr = NULL_TREE;
6145 saved_class_ref = current_class_ref;
6146 cp_function_chain->x_current_class_ref = NULL_TREE;
6149 push_deferring_access_checks(dk_no_deferred);
6150 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6151 tf_error | tf_warning, NULL_TREE);
6152 pop_deferring_access_checks();
6154 /* Restore the "this" pointer. */
6157 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6158 cp_function_chain->x_current_class_ref = saved_class_ref;
6161 pop_access_scope (fn);
6163 /* Make sure the default argument is reasonable. */
6164 arg = check_default_argument (type, arg);
6169 /* Substitute into all the default arguments for FN. */
6172 tsubst_default_arguments (tree fn)
6177 tmpl_args = DECL_TI_ARGS (fn);
6179 /* If this function is not yet instantiated, we certainly don't need
6180 its default arguments. */
6181 if (uses_template_parms (tmpl_args))
6184 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6186 arg = TREE_CHAIN (arg))
6187 if (TREE_PURPOSE (arg))
6188 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6190 TREE_PURPOSE (arg));
6193 /* Substitute the ARGS into the T, which is a _DECL. Return the
6194 result of the substitution. Issue error and warning messages under
6195 control of COMPLAIN. */
6198 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6200 location_t saved_loc;
6204 /* Set the filename and linenumber to improve error-reporting. */
6205 saved_loc = input_location;
6206 input_location = DECL_SOURCE_LOCATION (t);
6208 switch (TREE_CODE (t))
6212 /* We can get here when processing a member function template,
6213 member class template, and template template parameter of
6214 a template class. */
6215 tree decl = DECL_TEMPLATE_RESULT (t);
6220 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6222 /* Template template parameter is treated here. */
6223 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6224 if (new_type == error_mark_node)
6225 return error_mark_node;
6228 TREE_CHAIN (r) = NULL_TREE;
6229 TREE_TYPE (r) = new_type;
6230 DECL_TEMPLATE_RESULT (r)
6231 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6232 DECL_TEMPLATE_PARMS (r)
6233 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6235 TYPE_NAME (new_type) = r;
6239 /* We might already have an instance of this template.
6240 The ARGS are for the surrounding class type, so the
6241 full args contain the tsubst'd args for the context,
6242 plus the innermost args from the template decl. */
6243 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6244 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6245 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6246 full_args = tsubst_template_args (tmpl_args, args,
6248 if (full_args == error_mark_node)
6249 return error_mark_node;
6251 /* tsubst_template_args doesn't copy the vector if
6252 nothing changed. But, *something* should have
6254 gcc_assert (full_args != tmpl_args);
6256 spec = retrieve_specialization (t, full_args,
6257 /*class_specializations_p=*/true);
6258 if (spec != NULL_TREE)
6264 /* Make a new template decl. It will be similar to the
6265 original, but will record the current template arguments.
6266 We also create a new function declaration, which is just
6267 like the old one, but points to this new template, rather
6268 than the old one. */
6270 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6271 TREE_CHAIN (r) = NULL_TREE;
6274 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6276 /*entering_scope=*/1);
6277 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6279 if (TREE_CODE (decl) == TYPE_DECL)
6281 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6282 if (new_type == error_mark_node)
6283 return error_mark_node;
6285 TREE_TYPE (r) = new_type;
6286 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6287 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6288 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6292 tree new_decl = tsubst (decl, args, complain, in_decl);
6293 if (new_decl == error_mark_node)
6294 return error_mark_node;
6296 DECL_TEMPLATE_RESULT (r) = new_decl;
6297 DECL_TI_TEMPLATE (new_decl) = r;
6298 TREE_TYPE (r) = TREE_TYPE (new_decl);
6299 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6302 SET_DECL_IMPLICIT_INSTANTIATION (r);
6303 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6304 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6306 /* The template parameters for this new template are all the
6307 template parameters for the old template, except the
6308 outermost level of parameters. */
6309 DECL_TEMPLATE_PARMS (r)
6310 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6313 if (PRIMARY_TEMPLATE_P (t))
6314 DECL_PRIMARY_TEMPLATE (r) = r;
6316 if (TREE_CODE (decl) != TYPE_DECL)
6317 /* Record this non-type partial instantiation. */
6318 register_specialization (r, t,
6319 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
6327 tree argvec = NULL_TREE;
6335 /* Nobody should be tsubst'ing into non-template functions. */
6336 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6338 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6343 /* If T is not dependent, just return it. We have to
6344 increment PROCESSING_TEMPLATE_DECL because
6345 value_dependent_expression_p assumes that nothing is
6346 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6347 ++processing_template_decl;
6348 dependent_p = value_dependent_expression_p (t);
6349 --processing_template_decl;
6353 /* Calculate the most general template of which R is a
6354 specialization, and the complete set of arguments used to
6356 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6357 argvec = tsubst_template_args (DECL_TI_ARGS
6358 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6359 args, complain, in_decl);
6361 /* Check to see if we already have this specialization. */
6362 spec = retrieve_specialization (gen_tmpl, argvec,
6363 /*class_specializations_p=*/false);
6371 /* We can see more levels of arguments than parameters if
6372 there was a specialization of a member template, like
6375 template <class T> struct S { template <class U> void f(); }
6376 template <> template <class U> void S<int>::f(U);
6378 Here, we'll be substituting into the specialization,
6379 because that's where we can find the code we actually
6380 want to generate, but we'll have enough arguments for
6381 the most general template.
6383 We also deal with the peculiar case:
6385 template <class T> struct S {
6386 template <class U> friend void f();
6388 template <class U> void f() {}
6390 template void f<double>();
6392 Here, the ARGS for the instantiation of will be {int,
6393 double}. But, we only need as many ARGS as there are
6394 levels of template parameters in CODE_PATTERN. We are
6395 careful not to get fooled into reducing the ARGS in
6398 template <class T> struct S { template <class U> void f(U); }
6399 template <class T> template <> void S<T>::f(int) {}
6401 which we can spot because the pattern will be a
6402 specialization in this case. */
6403 args_depth = TMPL_ARGS_DEPTH (args);
6405 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6406 if (args_depth > parms_depth
6407 && !DECL_TEMPLATE_SPECIALIZATION (t))
6408 args = get_innermost_template_args (args, parms_depth);
6412 /* This special case arises when we have something like this:
6414 template <class T> struct S {
6415 friend void f<int>(int, double);
6418 Here, the DECL_TI_TEMPLATE for the friend declaration
6419 will be an IDENTIFIER_NODE. We are being called from
6420 tsubst_friend_function, and we want only to create a
6421 new decl (R) with appropriate types so that we can call
6422 determine_specialization. */
6423 gen_tmpl = NULL_TREE;
6426 if (DECL_CLASS_SCOPE_P (t))
6428 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6432 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6433 complain, t, /*entering_scope=*/1);
6438 ctx = DECL_CONTEXT (t);
6440 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6441 if (type == error_mark_node)
6442 return error_mark_node;
6444 /* We do NOT check for matching decls pushed separately at this
6445 point, as they may not represent instantiations of this
6446 template, and in any case are considered separate under the
6449 DECL_USE_TEMPLATE (r) = 0;
6450 TREE_TYPE (r) = type;
6451 /* Clear out the mangled name and RTL for the instantiation. */
6452 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6453 SET_DECL_RTL (r, NULL_RTX);
6454 DECL_INITIAL (r) = NULL_TREE;
6455 DECL_CONTEXT (r) = ctx;
6457 if (member && DECL_CONV_FN_P (r))
6458 /* Type-conversion operator. Reconstruct the name, in
6459 case it's the name of one of the template's parameters. */
6460 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6462 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6464 DECL_RESULT (r) = NULL_TREE;
6466 TREE_STATIC (r) = 0;
6467 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6468 DECL_EXTERNAL (r) = 1;
6469 /* If this is an instantiation of a function with internal
6470 linkage, we already know what object file linkage will be
6471 assigned to the instantiation. */
6472 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6473 DECL_DEFER_OUTPUT (r) = 0;
6474 TREE_CHAIN (r) = NULL_TREE;
6475 DECL_PENDING_INLINE_INFO (r) = 0;
6476 DECL_PENDING_INLINE_P (r) = 0;
6477 DECL_SAVED_TREE (r) = NULL_TREE;
6479 if (DECL_CLONED_FUNCTION (r))
6481 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6483 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6484 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6487 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6488 this in the special friend case mentioned above where
6489 GEN_TMPL is NULL. */
6492 DECL_TEMPLATE_INFO (r)
6493 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6494 SET_DECL_IMPLICIT_INSTANTIATION (r);
6495 register_specialization (r, gen_tmpl, argvec, false);
6497 /* We're not supposed to instantiate default arguments
6498 until they are called, for a template. But, for a
6501 template <class T> void f ()
6502 { extern void g(int i = T()); }
6504 we should do the substitution when the template is
6505 instantiated. We handle the member function case in
6506 instantiate_class_template since the default arguments
6507 might refer to other members of the class. */
6509 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6510 && !uses_template_parms (argvec))
6511 tsubst_default_arguments (r);
6514 /* Copy the list of befriending classes. */
6515 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6517 friends = &TREE_CHAIN (*friends))
6519 *friends = copy_node (*friends);
6520 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6525 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6527 maybe_retrofit_in_chrg (r);
6528 if (DECL_CONSTRUCTOR_P (r))
6529 grok_ctor_properties (ctx, r);
6530 /* If this is an instantiation of a member template, clone it.
6531 If it isn't, that'll be handled by
6532 clone_constructors_and_destructors. */
6533 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6534 clone_function_decl (r, /*update_method_vec_p=*/0);
6536 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6537 grok_op_properties (r, (complain & tf_error) != 0);
6539 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6540 SET_DECL_FRIEND_CONTEXT (r,
6541 tsubst (DECL_FRIEND_CONTEXT (t),
6542 args, complain, in_decl));
6551 if (DECL_TEMPLATE_PARM_P (t))
6552 SET_DECL_TEMPLATE_PARM_P (r);
6554 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6555 type = type_decays_to (type);
6556 TREE_TYPE (r) = type;
6557 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6559 if (DECL_INITIAL (r))
6561 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6562 DECL_INITIAL (r) = TREE_TYPE (r);
6564 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6568 DECL_CONTEXT (r) = NULL_TREE;
6570 if (!DECL_TEMPLATE_PARM_P (r))
6571 DECL_ARG_TYPE (r) = type_passed_as (type);
6573 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6574 complain, TREE_CHAIN (t));
6583 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6584 if (type == error_mark_node)
6585 return error_mark_node;
6586 TREE_TYPE (r) = type;
6587 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6589 /* We don't have to set DECL_CONTEXT here; it is set by
6590 finish_member_declaration. */
6591 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6593 TREE_CHAIN (r) = NULL_TREE;
6594 if (VOID_TYPE_P (type))
6595 error ("instantiation of %q+D as type %qT", r, type);
6600 /* We reach here only for member using decls. */
6601 if (DECL_DEPENDENT_P (t))
6603 r = do_class_using_decl
6604 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
6605 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
6607 r = error_mark_node;
6612 TREE_CHAIN (r) = NULL_TREE;
6619 tree argvec = NULL_TREE;
6620 tree gen_tmpl = NULL_TREE;
6622 tree tmpl = NULL_TREE;
6624 tree type = NULL_TREE;
6627 if (TREE_CODE (t) == TYPE_DECL)
6629 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6630 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6631 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6633 /* If this is the canonical decl, we don't have to
6634 mess with instantiations, and often we can't (for
6635 typename, template type parms and such). Note that
6636 TYPE_NAME is not correct for the above test if
6637 we've copied the type for a typedef. */
6638 r = TYPE_NAME (type);
6643 /* Assume this is a non-local variable. */
6646 if (TYPE_P (CP_DECL_CONTEXT (t)))
6647 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6649 in_decl, /*entering_scope=*/1);
6650 else if (DECL_NAMESPACE_SCOPE_P (t))
6651 ctx = DECL_CONTEXT (t);
6654 /* Subsequent calls to pushdecl will fill this in. */
6659 /* Check to see if we already have this specialization. */
6662 tmpl = DECL_TI_TEMPLATE (t);
6663 gen_tmpl = most_general_template (tmpl);
6664 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6665 spec = retrieve_specialization (gen_tmpl, argvec,
6666 /*class_specializations_p=*/false);
6669 spec = retrieve_local_specialization (t);
6678 if (TREE_CODE (r) == VAR_DECL)
6680 /* Even if the original location is out of scope, the
6681 newly substituted one is not. */
6682 DECL_DEAD_FOR_LOCAL (r) = 0;
6683 DECL_INITIALIZED_P (r) = 0;
6684 DECL_TEMPLATE_INSTANTIATED (r) = 0;
6685 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6686 if (type == error_mark_node)
6687 return error_mark_node;
6688 type = complete_type (type);
6689 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6690 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6691 type = check_var_type (DECL_NAME (r), type);
6693 if (DECL_HAS_VALUE_EXPR_P (t))
6695 tree ve = DECL_VALUE_EXPR (t);
6696 ve = tsubst_expr (ve, args, complain, in_decl);
6697 SET_DECL_VALUE_EXPR (r, ve);
6700 else if (DECL_SELF_REFERENCE_P (t))
6701 SET_DECL_SELF_REFERENCE_P (r);
6702 TREE_TYPE (r) = type;
6703 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6704 DECL_CONTEXT (r) = ctx;
6705 /* Clear out the mangled name and RTL for the instantiation. */
6706 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6707 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6708 SET_DECL_RTL (r, NULL_RTX);
6709 /* The initializer must not be expanded until it is required;
6711 DECL_INITIAL (r) = NULL_TREE;
6712 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6713 SET_DECL_RTL (r, NULL_RTX);
6714 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6718 /* A static data member declaration is always marked
6719 external when it is declared in-class, even if an
6720 initializer is present. We mimic the non-template
6722 DECL_EXTERNAL (r) = 1;
6724 register_specialization (r, gen_tmpl, argvec, false);
6725 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6726 SET_DECL_IMPLICIT_INSTANTIATION (r);
6729 register_local_specialization (r, t);
6731 TREE_CHAIN (r) = NULL_TREE;
6740 /* Restore the file and line information. */
6741 input_location = saved_loc;
6746 /* Substitute into the ARG_TYPES of a function type. */
6749 tsubst_arg_types (tree arg_types,
6751 tsubst_flags_t complain,
6754 tree remaining_arg_types;
6757 tree result = NULL_TREE;
6759 if (!arg_types || arg_types == void_list_node)
6762 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6763 args, complain, in_decl);
6764 if (remaining_arg_types == error_mark_node)
6765 return error_mark_node;
6767 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6768 if (type == error_mark_node)
6769 return error_mark_node;
6770 if (VOID_TYPE_P (type))
6772 if (complain & tf_error)
6774 error ("invalid parameter type %qT", type);
6776 error ("in declaration %q+D", in_decl);
6778 return error_mark_node;
6781 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6782 top-level qualifiers as required. */
6783 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6785 /* We do not substitute into default arguments here. The standard
6786 mandates that they be instantiated only when needed, which is
6787 done in build_over_call. */
6788 default_arg = TREE_PURPOSE (arg_types);
6790 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
6792 /* We've instantiated a template before its default arguments
6793 have been parsed. This can happen for a nested template
6794 class, and is not an error unless we require the default
6795 argument in a call of this function. */
6796 result = tree_cons (default_arg, type, remaining_arg_types);
6797 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), result);
6800 result = hash_tree_cons (default_arg, type, remaining_arg_types);
6805 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6806 *not* handle the exception-specification for FNTYPE, because the
6807 initial substitution of explicitly provided template parameters
6808 during argument deduction forbids substitution into the
6809 exception-specification:
6813 All references in the function type of the function template to the
6814 corresponding template parameters are replaced by the specified tem-
6815 plate argument values. If a substitution in a template parameter or
6816 in the function type of the function template results in an invalid
6817 type, type deduction fails. [Note: The equivalent substitution in
6818 exception specifications is done only when the function is instanti-
6819 ated, at which point a program is ill-formed if the substitution
6820 results in an invalid type.] */
6823 tsubst_function_type (tree t,
6825 tsubst_flags_t complain,
6832 /* The TYPE_CONTEXT is not used for function/method types. */
6833 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6835 /* Substitute the return type. */
6836 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6837 if (return_type == error_mark_node)
6838 return error_mark_node;
6839 /* The standard does not presently indicate that creation of a
6840 function type with an invalid return type is a deduction failure.
6841 However, that is clearly analogous to creating an array of "void"
6842 or a reference to a reference. This is core issue #486. */
6843 if (TREE_CODE (return_type) == ARRAY_TYPE
6844 || TREE_CODE (return_type) == FUNCTION_TYPE)
6846 if (complain & tf_error)
6848 if (TREE_CODE (return_type) == ARRAY_TYPE)
6849 error ("function returning an array");
6851 error ("function returning a function");
6853 return error_mark_node;
6856 /* Substitute the argument types. */
6857 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6859 if (arg_types == error_mark_node)
6860 return error_mark_node;
6862 /* Construct a new type node and return it. */
6863 if (TREE_CODE (t) == FUNCTION_TYPE)
6864 fntype = build_function_type (return_type, arg_types);
6867 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6868 if (! IS_AGGR_TYPE (r))
6872 Type deduction may fail for any of the following
6875 -- Attempting to create "pointer to member of T" when T
6876 is not a class type. */
6877 if (complain & tf_error)
6878 error ("creating pointer to member function of non-class type %qT",
6880 return error_mark_node;
6883 fntype = build_method_type_directly (r, return_type,
6884 TREE_CHAIN (arg_types));
6886 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6887 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6892 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6893 ARGS into that specification, and return the substituted
6894 specification. If there is no specification, return NULL_TREE. */
6897 tsubst_exception_specification (tree fntype,
6899 tsubst_flags_t complain,
6905 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6906 new_specs = NULL_TREE;
6909 if (! TREE_VALUE (specs))
6915 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6916 if (spec == error_mark_node)
6918 new_specs = add_exception_specifier (new_specs, spec, complain);
6919 specs = TREE_CHAIN (specs);
6925 /* Substitute into the PARMS of a call-declarator. */
6928 tsubst_call_declarator_parms (tree parms,
6930 tsubst_flags_t complain,
6937 if (!parms || parms == void_list_node)
6940 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6941 args, complain, in_decl);
6943 /* Figure out the type of this parameter. */
6944 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6946 /* Figure out the default argument as well. Note that we use
6947 tsubst_expr since the default argument is really an expression. */
6948 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6950 /* Chain this parameter on to the front of those we have already
6951 processed. We don't use hash_tree_cons because that function
6952 doesn't check TREE_PARMLIST. */
6953 new_parms = tree_cons (defarg, type, new_parms);
6958 /* Take the tree structure T and replace template parameters used
6959 therein with the argument vector ARGS. IN_DECL is an associated
6960 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6961 Issue error and warning messages under control of COMPLAIN. Note
6962 that we must be relatively non-tolerant of extensions here, in
6963 order to preserve conformance; if we allow substitutions that
6964 should not be allowed, we may allow argument deductions that should
6965 not succeed, and therefore report ambiguous overload situations
6966 where there are none. In theory, we could allow the substitution,
6967 but indicate that it should have failed, and allow our caller to
6968 make sure that the right thing happens, but we don't try to do this
6971 This function is used for dealing with types, decls and the like;
6972 for expressions, use tsubst_expr or tsubst_copy. */
6975 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6979 if (t == NULL_TREE || t == error_mark_node
6980 || t == integer_type_node
6981 || t == void_type_node
6982 || t == char_type_node
6983 || t == unknown_type_node
6984 || TREE_CODE (t) == NAMESPACE_DECL)
6988 return tsubst_decl (t, args, complain);
6990 if (TREE_CODE (t) == IDENTIFIER_NODE)
6991 type = IDENTIFIER_TYPE_VALUE (t);
6993 type = TREE_TYPE (t);
6995 gcc_assert (type != unknown_type_node);
6998 && TREE_CODE (t) != TYPENAME_TYPE
6999 && TREE_CODE (t) != IDENTIFIER_NODE
7000 && TREE_CODE (t) != FUNCTION_TYPE
7001 && TREE_CODE (t) != METHOD_TYPE)
7002 type = tsubst (type, args, complain, in_decl);
7003 if (type == error_mark_node)
7004 return error_mark_node;
7006 switch (TREE_CODE (t))
7011 return tsubst_aggr_type (t, args, complain, in_decl,
7012 /*entering_scope=*/0);
7015 case IDENTIFIER_NODE:
7027 if (t == integer_type_node)
7030 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
7031 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
7035 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
7037 /* The array dimension behaves like a non-type template arg,
7038 in that we want to fold it as much as possible. */
7039 max = tsubst_template_arg (omax, args, complain, in_decl);
7040 max = fold_decl_constant_value (max);
7042 if (integer_zerop (omax))
7044 /* Still allow an explicit array of size zero. */
7046 pedwarn ("creating array with size zero");
7048 else if (integer_zerop (max)
7049 || (TREE_CODE (max) == INTEGER_CST
7050 && INT_CST_LT (max, integer_zero_node)))
7054 Type deduction may fail for any of the following
7057 Attempting to create an array with a size that is
7058 zero or negative. */
7059 if (complain & tf_error)
7060 error ("creating array with size zero (%qE)", max);
7062 return error_mark_node;
7065 return compute_array_index_type (NULL_TREE, max);
7068 case TEMPLATE_TYPE_PARM:
7069 case TEMPLATE_TEMPLATE_PARM:
7070 case BOUND_TEMPLATE_TEMPLATE_PARM:
7071 case TEMPLATE_PARM_INDEX:
7076 tree arg = NULL_TREE;
7080 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7081 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7082 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7083 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7085 idx = TEMPLATE_TYPE_IDX (t);
7086 level = TEMPLATE_TYPE_LEVEL (t);
7090 idx = TEMPLATE_PARM_IDX (t);
7091 level = TEMPLATE_PARM_LEVEL (t);
7094 levels = TMPL_ARGS_DEPTH (args);
7095 if (level <= levels)
7096 arg = TMPL_ARG (args, level, idx);
7098 if (arg == error_mark_node)
7099 return error_mark_node;
7100 else if (arg != NULL_TREE)
7102 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7104 gcc_assert (TYPE_P (arg));
7105 return cp_build_qualified_type_real
7106 (arg, cp_type_quals (arg) | cp_type_quals (t),
7107 complain | tf_ignore_bad_quals);
7109 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7111 /* We are processing a type constructed from a
7112 template template parameter. */
7113 tree argvec = tsubst (TYPE_TI_ARGS (t),
7114 args, complain, in_decl);
7115 if (argvec == error_mark_node)
7116 return error_mark_node;
7118 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7119 are resolving nested-types in the signature of a
7120 member function templates. Otherwise ARG is a
7121 TEMPLATE_DECL and is the real template to be
7123 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7124 arg = TYPE_NAME (arg);
7126 r = lookup_template_class (arg,
7129 /*entering_scope=*/0,
7131 return cp_build_qualified_type_real
7132 (r, TYPE_QUALS (t), complain);
7135 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7140 /* This can happen during the attempted tsubst'ing in
7141 unify. This means that we don't yet have any information
7142 about the template parameter in question. */
7145 /* If we get here, we must have been looking at a parm for a
7146 more deeply nested template. Make a new version of this
7147 template parameter, but with a lower level. */
7148 switch (TREE_CODE (t))
7150 case TEMPLATE_TYPE_PARM:
7151 case TEMPLATE_TEMPLATE_PARM:
7152 case BOUND_TEMPLATE_TEMPLATE_PARM:
7153 if (cp_type_quals (t))
7155 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7156 r = cp_build_qualified_type_real
7157 (r, cp_type_quals (t),
7158 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7159 ? tf_ignore_bad_quals : 0));
7164 TEMPLATE_TYPE_PARM_INDEX (r)
7165 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7167 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7168 TYPE_MAIN_VARIANT (r) = r;
7169 TYPE_POINTER_TO (r) = NULL_TREE;
7170 TYPE_REFERENCE_TO (r) = NULL_TREE;
7172 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7174 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7176 if (argvec == error_mark_node)
7177 return error_mark_node;
7179 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7180 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7185 case TEMPLATE_PARM_INDEX:
7186 r = reduce_template_parm_level (t, type, levels);
7198 tree purpose, value, chain;
7200 if (t == void_list_node)
7203 purpose = TREE_PURPOSE (t);
7206 purpose = tsubst (purpose, args, complain, in_decl);
7207 if (purpose == error_mark_node)
7208 return error_mark_node;
7210 value = TREE_VALUE (t);
7213 value = tsubst (value, args, complain, in_decl);
7214 if (value == error_mark_node)
7215 return error_mark_node;
7217 chain = TREE_CHAIN (t);
7218 if (chain && chain != void_type_node)
7220 chain = tsubst (chain, args, complain, in_decl);
7221 if (chain == error_mark_node)
7222 return error_mark_node;
7224 if (purpose == TREE_PURPOSE (t)
7225 && value == TREE_VALUE (t)
7226 && chain == TREE_CHAIN (t))
7228 return hash_tree_cons (purpose, value, chain);
7232 /* We should never be tsubsting a binfo. */
7236 /* A vector of template arguments. */
7238 return tsubst_template_args (t, args, complain, in_decl);
7241 case REFERENCE_TYPE:
7243 enum tree_code code;
7245 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7248 code = TREE_CODE (t);
7253 Type deduction may fail for any of the following
7256 -- Attempting to create a pointer to reference type.
7257 -- Attempting to create a reference to a reference type or
7258 a reference to void. */
7259 if (TREE_CODE (type) == REFERENCE_TYPE
7260 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7262 static location_t last_loc;
7264 /* We keep track of the last time we issued this error
7265 message to avoid spewing a ton of messages during a
7266 single bad template instantiation. */
7267 if (complain & tf_error
7268 #ifdef USE_MAPPED_LOCATION
7269 && last_loc != input_location
7271 && (last_loc.line != input_line
7272 || last_loc.file != input_filename)
7276 if (TREE_CODE (type) == VOID_TYPE)
7277 error ("forming reference to void");
7279 error ("forming %s to reference type %qT",
7280 (code == POINTER_TYPE) ? "pointer" : "reference",
7282 last_loc = input_location;
7285 return error_mark_node;
7287 else if (code == POINTER_TYPE)
7289 r = build_pointer_type (type);
7290 if (TREE_CODE (type) == METHOD_TYPE)
7291 r = build_ptrmemfunc_type (r);
7294 r = build_reference_type (type);
7295 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7297 if (r != error_mark_node)
7298 /* Will this ever be needed for TYPE_..._TO values? */
7305 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7306 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7310 Type deduction may fail for any of the following
7313 -- Attempting to create "pointer to member of T" when T
7314 is not a class type. */
7315 if (complain & tf_error)
7316 error ("creating pointer to member of non-class type %qT", r);
7317 return error_mark_node;
7319 if (TREE_CODE (type) == REFERENCE_TYPE)
7321 if (complain & tf_error)
7322 error ("creating pointer to member reference type %qT", type);
7323 return error_mark_node;
7325 if (TREE_CODE (type) == VOID_TYPE)
7327 if (complain & tf_error)
7328 error ("creating pointer to member of type void");
7329 return error_mark_node;
7331 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7332 if (TREE_CODE (type) == FUNCTION_TYPE)
7334 /* The type of the implicit object parameter gets its
7335 cv-qualifiers from the FUNCTION_TYPE. */
7337 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
7338 cp_type_quals (type));
7340 method_type = build_method_type_directly (this_type,
7342 TYPE_ARG_TYPES (type));
7343 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
7344 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
7348 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7357 fntype = tsubst_function_type (t, args, complain, in_decl);
7358 if (fntype == error_mark_node)
7359 return error_mark_node;
7361 /* Substitute the exception specification. */
7362 specs = tsubst_exception_specification (t, args, complain,
7364 if (specs == error_mark_node)
7365 return error_mark_node;
7367 fntype = build_exception_variant (fntype, specs);
7372 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7373 if (domain == error_mark_node)
7374 return error_mark_node;
7376 /* As an optimization, we avoid regenerating the array type if
7377 it will obviously be the same as T. */
7378 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7381 /* These checks should match the ones in grokdeclarator.
7385 The deduction may fail for any of the following reasons:
7387 -- Attempting to create an array with an element type that
7388 is void, a function type, or a reference type, or [DR337]
7389 an abstract class type. */
7390 if (TREE_CODE (type) == VOID_TYPE
7391 || TREE_CODE (type) == FUNCTION_TYPE
7392 || TREE_CODE (type) == REFERENCE_TYPE)
7394 if (complain & tf_error)
7395 error ("creating array of %qT", type);
7396 return error_mark_node;
7398 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7400 if (complain & tf_error)
7401 error ("creating array of %qT, which is an abstract class type",
7403 return error_mark_node;
7406 r = build_cplus_array_type (type, domain);
7413 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7414 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7416 if (e1 == error_mark_node || e2 == error_mark_node)
7417 return error_mark_node;
7419 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
7425 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7426 if (e == error_mark_node)
7427 return error_mark_node;
7429 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
7434 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7435 in_decl, /*entering_scope=*/1);
7436 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7439 if (ctx == error_mark_node || f == error_mark_node)
7440 return error_mark_node;
7442 if (!IS_AGGR_TYPE (ctx))
7444 if (complain & tf_error)
7445 error ("%qT is not a class, struct, or union type", ctx);
7446 return error_mark_node;
7448 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7450 /* Normally, make_typename_type does not require that the CTX
7451 have complete type in order to allow things like:
7453 template <class T> struct S { typename S<T>::X Y; };
7455 But, such constructs have already been resolved by this
7456 point, so here CTX really should have complete type, unless
7457 it's a partial instantiation. */
7458 ctx = complete_type (ctx);
7459 if (!COMPLETE_TYPE_P (ctx))
7461 if (complain & tf_error)
7462 cxx_incomplete_type_error (NULL_TREE, ctx);
7463 return error_mark_node;
7467 f = make_typename_type (ctx, f, typename_type,
7468 (complain & tf_error) | tf_keep_type_decl);
7469 if (f == error_mark_node)
7471 if (TREE_CODE (f) == TYPE_DECL)
7473 complain |= tf_ignore_bad_quals;
7477 if (TREE_CODE (f) != TYPENAME_TYPE)
7479 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7480 error ("%qT resolves to %qT, which is not an enumeration type",
7482 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7483 error ("%qT resolves to %qT, which is is not a class type",
7487 return cp_build_qualified_type_real
7488 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7491 case UNBOUND_CLASS_TEMPLATE:
7493 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7494 in_decl, /*entering_scope=*/1);
7495 tree name = TYPE_IDENTIFIER (t);
7496 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7498 if (ctx == error_mark_node || name == error_mark_node)
7499 return error_mark_node;
7502 parm_list = tsubst_template_parms (parm_list, args, complain);
7503 return make_unbound_class_template (ctx, name, parm_list, complain);
7513 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7514 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7515 if (e1 == error_mark_node || e2 == error_mark_node)
7516 return error_mark_node;
7518 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7523 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7524 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7525 if (e1 == error_mark_node || e2 == error_mark_node)
7526 return error_mark_node;
7528 return build_nt (TREE_CODE (t), e1, e2);
7535 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7536 complain, in_decl));
7537 return cp_build_qualified_type_real (type,
7539 | cp_type_quals (type),
7544 sorry ("use of %qs in template",
7545 tree_code_name [(int) TREE_CODE (t)]);
7546 return error_mark_node;
7550 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7551 type of the expression on the left-hand side of the "." or "->"
7555 tsubst_baselink (tree baselink, tree object_type,
7556 tree args, tsubst_flags_t complain, tree in_decl)
7559 tree qualifying_scope;
7561 tree template_args = 0;
7562 bool template_id_p = false;
7564 /* A baselink indicates a function from a base class. The
7565 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7566 non-dependent types; otherwise, the lookup could not have
7567 succeeded. However, they may indicate bases of the template
7568 class, rather than the instantiated class.
7570 In addition, lookups that were not ambiguous before may be
7571 ambiguous now. Therefore, we perform the lookup again. */
7572 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7573 fns = BASELINK_FUNCTIONS (baselink);
7574 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7576 template_id_p = true;
7577 template_args = TREE_OPERAND (fns, 1);
7578 fns = TREE_OPERAND (fns, 0);
7580 template_args = tsubst_template_args (template_args, args,
7583 name = DECL_NAME (get_first_fn (fns));
7584 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7586 /* If lookup found a single function, mark it as used at this
7587 point. (If it lookup found multiple functions the one selected
7588 later by overload resolution will be marked as used at that
7590 if (BASELINK_P (baselink))
7591 fns = BASELINK_FUNCTIONS (baselink);
7592 if (!template_id_p && !really_overloaded_fn (fns))
7593 mark_used (OVL_CURRENT (fns));
7595 /* Add back the template arguments, if present. */
7596 if (BASELINK_P (baselink) && template_id_p)
7597 BASELINK_FUNCTIONS (baselink)
7598 = build_nt (TEMPLATE_ID_EXPR,
7599 BASELINK_FUNCTIONS (baselink),
7603 object_type = current_class_type;
7604 return adjust_result_of_qualified_name_lookup (baselink,
7609 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7610 true if the qualified-id will be a postfix-expression in-and-of
7611 itself; false if more of the postfix-expression follows the
7612 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7616 tsubst_qualified_id (tree qualified_id, tree args,
7617 tsubst_flags_t complain, tree in_decl,
7618 bool done, bool address_p)
7626 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7628 /* Figure out what name to look up. */
7629 name = TREE_OPERAND (qualified_id, 1);
7630 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7633 template_args = TREE_OPERAND (name, 1);
7635 template_args = tsubst_template_args (template_args, args,
7637 name = TREE_OPERAND (name, 0);
7641 is_template = false;
7642 template_args = NULL_TREE;
7645 /* Substitute into the qualifying scope. When there are no ARGS, we
7646 are just trying to simplify a non-dependent expression. In that
7647 case the qualifying scope may be dependent, and, in any case,
7648 substituting will not help. */
7649 scope = TREE_OPERAND (qualified_id, 0);
7652 scope = tsubst (scope, args, complain, in_decl);
7653 expr = tsubst_copy (name, args, complain, in_decl);
7658 if (dependent_type_p (scope))
7659 return build_nt (SCOPE_REF, scope, expr);
7661 if (!BASELINK_P (name) && !DECL_P (expr))
7663 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7664 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7665 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7667 if (complain & tf_error)
7669 error ("dependent-name %qE is parsed as a non-type, but "
7670 "instantiation yields a type", qualified_id);
7671 inform ("say %<typename %E%> if a type is meant", qualified_id);
7673 return error_mark_node;
7679 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7681 /* Remember that there was a reference to this entity. */
7685 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7687 if (complain & tf_error)
7688 qualified_name_lookup_error (scope,
7689 TREE_OPERAND (qualified_id, 1),
7691 return error_mark_node;
7695 expr = lookup_template_function (expr, template_args);
7697 if (expr == error_mark_node && complain & tf_error)
7698 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7700 else if (TYPE_P (scope))
7702 expr = (adjust_result_of_qualified_name_lookup
7703 (expr, scope, current_class_type));
7704 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7707 if (TREE_CODE (expr) != SCOPE_REF)
7708 expr = convert_from_reference (expr);
7713 /* Like tsubst, but deals with expressions. This function just replaces
7714 template parms; to finish processing the resultant expression, use
7718 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7720 enum tree_code code;
7723 if (t == NULL_TREE || t == error_mark_node)
7726 code = TREE_CODE (t);
7731 r = retrieve_local_specialization (t);
7732 gcc_assert (r != NULL);
7741 if (DECL_TEMPLATE_PARM_P (t))
7742 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7743 /* There is no need to substitute into namespace-scope
7745 if (DECL_NAMESPACE_SCOPE_P (t))
7747 /* If ARGS is NULL, then T is known to be non-dependent. */
7748 if (args == NULL_TREE)
7749 return integral_constant_value (t);
7751 /* Unfortunately, we cannot just call lookup_name here.
7754 template <int I> int f() {
7756 struct S { void g() { E e = a; } };
7759 When we instantiate f<7>::S::g(), say, lookup_name is not
7760 clever enough to find f<7>::a. */
7762 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7763 /*entering_scope=*/0);
7765 for (v = TYPE_VALUES (enum_type);
7768 if (TREE_PURPOSE (v) == DECL_NAME (t))
7769 return TREE_VALUE (v);
7771 /* We didn't find the name. That should never happen; if
7772 name-lookup found it during preliminary parsing, we
7773 should find it again here during instantiation. */
7779 if (DECL_CONTEXT (t))
7783 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7784 /*entering_scope=*/1);
7785 if (ctx != DECL_CONTEXT (t))
7787 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7790 if (complain & tf_error)
7791 error ("using invalid field %qD", t);
7792 return error_mark_node;
7802 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7803 || local_variable_p (t))
7804 t = tsubst (t, args, complain, in_decl);
7809 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7812 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7813 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7814 args, complain, in_decl);
7815 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7816 return tsubst (t, args, complain, in_decl);
7817 else if (DECL_CLASS_SCOPE_P (t)
7818 && uses_template_parms (DECL_CONTEXT (t)))
7820 /* Template template argument like the following example need
7823 template <template <class> class TT> struct C {};
7824 template <class T> struct D {
7825 template <class U> struct E {};
7830 We are processing the template argument `E' in #1 for
7831 the template instantiation #2. Originally, `E' is a
7832 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7833 have to substitute this with one having context `D<int>'. */
7835 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7836 return lookup_field (context, DECL_NAME(t), 0, false);
7839 /* Ordinary template template argument. */
7843 case REINTERPRET_CAST_EXPR:
7844 case CONST_CAST_EXPR:
7845 case STATIC_CAST_EXPR:
7846 case DYNAMIC_CAST_EXPR:
7849 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7850 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7854 case TRUTH_NOT_EXPR:
7857 case UNARY_PLUS_EXPR: /* Unary + */
7866 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7867 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7874 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7875 name = TREE_OPERAND (t, 1);
7876 if (TREE_CODE (name) == BIT_NOT_EXPR)
7878 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7880 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7882 else if (TREE_CODE (name) == SCOPE_REF
7883 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7885 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7887 name = TREE_OPERAND (name, 1);
7888 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7890 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7891 name = build_nt (SCOPE_REF, base, name);
7893 else if (TREE_CODE (name) == BASELINK)
7894 name = tsubst_baselink (name,
7895 non_reference (TREE_TYPE (object)),
7899 name = tsubst_copy (name, args, complain, in_decl);
7900 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7906 case TRUNC_DIV_EXPR:
7908 case FLOOR_DIV_EXPR:
7909 case ROUND_DIV_EXPR:
7910 case EXACT_DIV_EXPR:
7914 case TRUNC_MOD_EXPR:
7915 case FLOOR_MOD_EXPR:
7916 case TRUTH_ANDIF_EXPR:
7917 case TRUTH_ORIF_EXPR:
7918 case TRUTH_AND_EXPR:
7936 case PREDECREMENT_EXPR:
7937 case PREINCREMENT_EXPR:
7938 case POSTDECREMENT_EXPR:
7939 case POSTINCREMENT_EXPR:
7941 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7942 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7947 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7948 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7949 NULL_TREE, NULL_TREE);
7952 return build_nt (code,
7953 tsubst_copy (TREE_OPERAND (t, 0), args,
7955 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7961 case PSEUDO_DTOR_EXPR:
7964 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7965 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7966 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7967 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7974 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7975 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7976 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7977 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7984 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7985 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7986 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7987 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7991 case TEMPLATE_ID_EXPR:
7993 /* Substituted template arguments */
7994 tree fn = TREE_OPERAND (t, 0);
7995 tree targs = TREE_OPERAND (t, 1);
7997 fn = tsubst_copy (fn, args, complain, in_decl);
7999 targs = tsubst_template_args (targs, args, complain, in_decl);
8001 return lookup_template_function (fn, targs);
8006 tree purpose, value, chain;
8008 if (t == void_list_node)
8011 purpose = TREE_PURPOSE (t);
8013 purpose = tsubst_copy (purpose, args, complain, in_decl);
8014 value = TREE_VALUE (t);
8016 value = tsubst_copy (value, args, complain, in_decl);
8017 chain = TREE_CHAIN (t);
8018 if (chain && chain != void_type_node)
8019 chain = tsubst_copy (chain, args, complain, in_decl);
8020 if (purpose == TREE_PURPOSE (t)
8021 && value == TREE_VALUE (t)
8022 && chain == TREE_CHAIN (t))
8024 return tree_cons (purpose, value, chain);
8031 case TEMPLATE_TYPE_PARM:
8032 case TEMPLATE_TEMPLATE_PARM:
8033 case BOUND_TEMPLATE_TEMPLATE_PARM:
8034 case TEMPLATE_PARM_INDEX:
8036 case REFERENCE_TYPE:
8042 case UNBOUND_CLASS_TEMPLATE:
8045 return tsubst (t, args, complain, in_decl);
8047 case IDENTIFIER_NODE:
8048 if (IDENTIFIER_TYPENAME_P (t))
8050 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8051 return mangle_conv_op_name_for_type (new_type);
8057 /* This is handled by tsubst_copy_and_build. */
8061 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8063 tsubst (TREE_TYPE (t), args, complain, in_decl));
8065 case CLEANUP_POINT_EXPR:
8066 /* We shouldn't have built any of these during initial template
8067 generation. Instead, they should be built during instantiation
8068 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8076 /* Like tsubst_copy for expressions, etc. but also does semantic
8080 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8084 if (t == NULL_TREE || t == error_mark_node)
8087 if (EXPR_HAS_LOCATION (t))
8088 input_location = EXPR_LOCATION (t);
8089 if (STATEMENT_CODE_P (TREE_CODE (t)))
8090 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8092 switch (TREE_CODE (t))
8094 case STATEMENT_LIST:
8096 tree_stmt_iterator i;
8097 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8098 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8102 case CTOR_INITIALIZER:
8103 finish_mem_initializers (tsubst_initializer_list
8104 (TREE_OPERAND (t, 0), args));
8108 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8109 args, complain, in_decl));
8113 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8114 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8115 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8117 finish_expr_stmt (tmp);
8121 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8122 args, complain, in_decl));
8130 decl = DECL_EXPR_DECL (t);
8131 if (TREE_CODE (decl) == LABEL_DECL)
8132 finish_label_decl (DECL_NAME (decl));
8133 else if (TREE_CODE (decl) == USING_DECL)
8135 tree scope = USING_DECL_SCOPE (decl);
8136 tree name = DECL_NAME (decl);
8139 scope = tsubst_expr (scope, args, complain, in_decl);
8140 decl = lookup_qualified_name (scope, name,
8141 /*is_type_p=*/false,
8142 /*complain=*/false);
8143 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8144 qualified_name_lookup_error (scope, name, decl);
8146 do_local_using_decl (decl, scope, name);
8150 init = DECL_INITIAL (decl);
8151 decl = tsubst (decl, args, complain, in_decl);
8152 if (decl != error_mark_node)
8155 DECL_INITIAL (decl) = error_mark_node;
8156 /* By marking the declaration as instantiated, we avoid
8157 trying to instantiate it. Since instantiate_decl can't
8158 handle local variables, and since we've already done
8159 all that needs to be done, that's the right thing to
8161 if (TREE_CODE (decl) == VAR_DECL)
8162 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8163 if (TREE_CODE (decl) == VAR_DECL
8164 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8165 /* Anonymous aggregates are a special case. */
8166 finish_anon_union (decl);
8169 maybe_push_decl (decl);
8170 if (TREE_CODE (decl) == VAR_DECL
8171 && DECL_PRETTY_FUNCTION_P (decl))
8173 /* For __PRETTY_FUNCTION__ we have to adjust the
8175 const char *const name
8176 = cxx_printable_name (current_function_decl, 2);
8177 init = cp_fname_init (name, &TREE_TYPE (decl));
8180 init = tsubst_expr (init, args, complain, in_decl);
8181 cp_finish_decl (decl, init, NULL_TREE, 0);
8186 /* A DECL_EXPR can also be used as an expression, in the condition
8187 clause of an if/for/while construct. */
8192 stmt = begin_for_stmt ();
8193 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8194 finish_for_init_stmt (stmt);
8195 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8196 finish_for_cond (tmp, stmt);
8197 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8198 finish_for_expr (tmp, stmt);
8199 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8200 finish_for_stmt (stmt);
8204 stmt = begin_while_stmt ();
8205 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8206 finish_while_stmt_cond (tmp, stmt);
8207 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8208 finish_while_stmt (stmt);
8212 stmt = begin_do_stmt ();
8213 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8214 finish_do_body (stmt);
8215 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8216 finish_do_stmt (tmp, stmt);
8220 stmt = begin_if_stmt ();
8221 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8222 finish_if_stmt_cond (tmp, stmt);
8223 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8224 finish_then_clause (stmt);
8226 if (ELSE_CLAUSE (t))
8228 begin_else_clause (stmt);
8229 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8230 finish_else_clause (stmt);
8233 finish_if_stmt (stmt);
8237 if (BIND_EXPR_BODY_BLOCK (t))
8238 stmt = begin_function_body ();
8240 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8241 ? BCS_TRY_BLOCK : 0);
8243 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8245 if (BIND_EXPR_BODY_BLOCK (t))
8246 finish_function_body (stmt);
8248 finish_compound_stmt (stmt);
8252 finish_break_stmt ();
8256 finish_continue_stmt ();
8260 stmt = begin_switch_stmt ();
8261 tmp = tsubst_expr (SWITCH_STMT_COND (t), args, complain, in_decl);
8262 finish_switch_cond (tmp, stmt);
8263 tsubst_expr (SWITCH_STMT_BODY (t), args, complain, in_decl);
8264 finish_switch_stmt (stmt);
8267 case CASE_LABEL_EXPR:
8268 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8269 tsubst_expr (CASE_HIGH (t), args, complain,
8274 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8278 tmp = GOTO_DESTINATION (t);
8279 if (TREE_CODE (tmp) != LABEL_DECL)
8280 /* Computed goto's must be tsubst'd into. On the other hand,
8281 non-computed gotos must not be; the identifier in question
8282 will have no binding. */
8283 tmp = tsubst_expr (tmp, args, complain, in_decl);
8285 tmp = DECL_NAME (tmp);
8286 finish_goto_stmt (tmp);
8290 tmp = finish_asm_stmt
8291 (ASM_VOLATILE_P (t),
8292 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8293 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8294 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8295 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8297 tree asm_expr = tmp;
8298 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8299 asm_expr = TREE_OPERAND (asm_expr, 0);
8300 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8307 stmt = begin_try_block ();
8308 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8309 finish_cleanup_try_block (stmt);
8310 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8316 if (FN_TRY_BLOCK_P (t))
8317 stmt = begin_function_try_block ();
8319 stmt = begin_try_block ();
8321 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8323 if (FN_TRY_BLOCK_P (t))
8324 finish_function_try_block (stmt);
8326 finish_try_block (stmt);
8328 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8329 if (FN_TRY_BLOCK_P (t))
8330 finish_function_handler_sequence (stmt);
8332 finish_handler_sequence (stmt);
8340 stmt = begin_handler ();
8341 if (HANDLER_PARMS (t))
8343 decl = HANDLER_PARMS (t);
8344 decl = tsubst (decl, args, complain, in_decl);
8345 /* Prevent instantiate_decl from trying to instantiate
8346 this variable. We've already done all that needs to be
8348 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8352 finish_handler_parms (decl, stmt);
8353 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8354 finish_handler (stmt);
8359 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8363 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8365 return tsubst_copy_and_build (t, args, complain, in_decl,
8366 /*function_p=*/false);
8372 /* T is a postfix-expression that is not being used in a function
8373 call. Return the substituted version of T. */
8376 tsubst_non_call_postfix_expression (tree t, tree args,
8377 tsubst_flags_t complain,
8380 if (TREE_CODE (t) == SCOPE_REF)
8381 t = tsubst_qualified_id (t, args, complain, in_decl,
8382 /*done=*/false, /*address_p=*/false);
8384 t = tsubst_copy_and_build (t, args, complain, in_decl,
8385 /*function_p=*/false);
8390 /* Like tsubst but deals with expressions and performs semantic
8391 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8394 tsubst_copy_and_build (tree t,
8396 tsubst_flags_t complain,
8400 #define RECUR(NODE) \
8401 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8405 if (t == NULL_TREE || t == error_mark_node)
8408 switch (TREE_CODE (t))
8413 case IDENTIFIER_NODE:
8417 tree qualifying_class;
8418 bool non_integral_constant_expression_p;
8419 const char *error_msg;
8421 if (IDENTIFIER_TYPENAME_P (t))
8423 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8424 t = mangle_conv_op_name_for_type (new_type);
8427 /* Look up the name. */
8428 decl = lookup_name (t, 0);
8430 /* By convention, expressions use ERROR_MARK_NODE to indicate
8431 failure, not NULL_TREE. */
8432 if (decl == NULL_TREE)
8433 decl = error_mark_node;
8435 decl = finish_id_expression (t, decl, NULL_TREE,
8438 /*integral_constant_expression_p=*/false,
8439 /*allow_non_integral_constant_expression_p=*/false,
8440 &non_integral_constant_expression_p,
8444 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8445 decl = unqualified_name_lookup_error (decl);
8449 case TEMPLATE_ID_EXPR:
8452 tree template = RECUR (TREE_OPERAND (t, 0));
8453 tree targs = TREE_OPERAND (t, 1);
8456 targs = tsubst_template_args (targs, args, complain, in_decl);
8458 if (TREE_CODE (template) == COMPONENT_REF)
8460 object = TREE_OPERAND (template, 0);
8461 template = TREE_OPERAND (template, 1);
8465 template = lookup_template_function (template, targs);
8468 return build3 (COMPONENT_REF, TREE_TYPE (template),
8469 object, template, NULL_TREE);
8476 tree r = RECUR (TREE_OPERAND (t, 0));
8478 if (REFERENCE_REF_P (t))
8480 /* A type conversion to reference type will be enclosed in
8481 such an indirect ref, but the substitution of the cast
8482 will have also added such an indirect ref. */
8483 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8484 r = convert_from_reference (r);
8487 r = build_x_indirect_ref (r, "unary *");
8493 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8494 RECUR (TREE_OPERAND (t, 0)));
8497 return build_functional_cast
8498 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8499 RECUR (TREE_OPERAND (t, 0)));
8501 case REINTERPRET_CAST_EXPR:
8502 return build_reinterpret_cast
8503 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8504 RECUR (TREE_OPERAND (t, 0)));
8506 case CONST_CAST_EXPR:
8507 return build_const_cast
8508 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8509 RECUR (TREE_OPERAND (t, 0)));
8511 case DYNAMIC_CAST_EXPR:
8512 return build_dynamic_cast
8513 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8514 RECUR (TREE_OPERAND (t, 0)));
8516 case STATIC_CAST_EXPR:
8517 return build_static_cast
8518 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8519 RECUR (TREE_OPERAND (t, 0)));
8521 case POSTDECREMENT_EXPR:
8522 case POSTINCREMENT_EXPR:
8523 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8524 args, complain, in_decl);
8525 return build_x_unary_op (TREE_CODE (t), op1);
8527 case PREDECREMENT_EXPR:
8528 case PREINCREMENT_EXPR:
8532 case TRUTH_NOT_EXPR:
8533 case UNARY_PLUS_EXPR: /* Unary + */
8536 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8539 op1 = TREE_OPERAND (t, 0);
8540 if (TREE_CODE (op1) == SCOPE_REF)
8541 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8542 /*done=*/true, /*address_p=*/true);
8544 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8546 if (TREE_CODE (op1) == LABEL_DECL)
8547 return finish_label_address_expr (DECL_NAME (op1));
8548 return build_x_unary_op (ADDR_EXPR, op1);
8553 case TRUNC_DIV_EXPR:
8555 case FLOOR_DIV_EXPR:
8556 case ROUND_DIV_EXPR:
8557 case EXACT_DIV_EXPR:
8561 case TRUNC_MOD_EXPR:
8562 case FLOOR_MOD_EXPR:
8563 case TRUTH_ANDIF_EXPR:
8564 case TRUTH_ORIF_EXPR:
8565 case TRUTH_AND_EXPR:
8581 return build_x_binary_op
8583 RECUR (TREE_OPERAND (t, 0)),
8584 RECUR (TREE_OPERAND (t, 1)),
8585 /*overloaded_p=*/NULL);
8588 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8589 /*address_p=*/false);
8591 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8592 args, complain, in_decl);
8593 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8594 /*overloaded_p=*/NULL);
8598 op1 = TREE_OPERAND (t, 0);
8601 /* When there are no ARGS, we are trying to evaluate a
8602 non-dependent expression from the parser. Trying to do
8603 the substitutions may not work. */
8605 op1 = TREE_TYPE (op1);
8614 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8616 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8620 tree r = build_x_modify_expr
8621 (RECUR (TREE_OPERAND (t, 0)),
8622 TREE_CODE (TREE_OPERAND (t, 1)),
8623 RECUR (TREE_OPERAND (t, 2)));
8624 /* TREE_NO_WARNING must be set if either the expression was
8625 parenthesized or it uses an operator such as >>= rather
8626 than plain assignment. In the former case, it was already
8627 set and must be copied. In the latter case,
8628 build_x_modify_expr sets it and it must not be reset
8630 if (TREE_NO_WARNING (t))
8631 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8636 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8637 args, complain, in_decl);
8638 /* Remember that there was a reference to this entity. */
8641 return build_x_arrow (op1);
8645 (RECUR (TREE_OPERAND (t, 0)),
8646 RECUR (TREE_OPERAND (t, 1)),
8647 RECUR (TREE_OPERAND (t, 2)),
8648 RECUR (TREE_OPERAND (t, 3)),
8649 NEW_EXPR_USE_GLOBAL (t));
8652 return delete_sanity
8653 (RECUR (TREE_OPERAND (t, 0)),
8654 RECUR (TREE_OPERAND (t, 1)),
8655 DELETE_EXPR_USE_VEC (t),
8656 DELETE_EXPR_USE_GLOBAL (t));
8659 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8660 RECUR (TREE_OPERAND (t, 1)));
8669 function = TREE_OPERAND (t, 0);
8670 /* When we parsed the expression, we determined whether or
8671 not Koenig lookup should be performed. */
8672 koenig_p = KOENIG_LOOKUP_P (t);
8673 if (TREE_CODE (function) == SCOPE_REF)
8676 function = tsubst_qualified_id (function, args, complain, in_decl,
8678 /*address_p=*/false);
8682 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8683 && (TREE_CODE (TREE_OPERAND (function, 1))
8685 function = tsubst_copy_and_build (function, args, complain,
8688 if (BASELINK_P (function))
8692 call_args = RECUR (TREE_OPERAND (t, 1));
8694 /* We do not perform argument-dependent lookup if normal
8695 lookup finds a non-function, in accordance with the
8696 expected resolution of DR 218. */
8698 && ((is_overloaded_fn (function)
8699 /* If lookup found a member function, the Koenig lookup is
8700 not appropriate, even if an unqualified-name was used
8701 to denote the function. */
8702 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8703 || TREE_CODE (function) == IDENTIFIER_NODE))
8704 function = perform_koenig_lookup (function, call_args);
8706 if (TREE_CODE (function) == IDENTIFIER_NODE)
8708 unqualified_name_lookup_error (function);
8709 return error_mark_node;
8712 /* Remember that there was a reference to this entity. */
8713 if (DECL_P (function))
8714 mark_used (function);
8716 if (TREE_CODE (function) == OFFSET_REF)
8717 return build_offset_ref_call_from_tree (function, call_args);
8718 if (TREE_CODE (function) == COMPONENT_REF)
8720 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8721 return finish_call_expr (function, call_args,
8722 /*disallow_virtual=*/false,
8723 /*koenig_p=*/false);
8725 return (build_new_method_call
8726 (TREE_OPERAND (function, 0),
8727 TREE_OPERAND (function, 1),
8728 call_args, NULL_TREE,
8729 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8731 return finish_call_expr (function, call_args,
8732 /*disallow_virtual=*/qualified_p,
8737 return build_x_conditional_expr
8738 (RECUR (TREE_OPERAND (t, 0)),
8739 RECUR (TREE_OPERAND (t, 1)),
8740 RECUR (TREE_OPERAND (t, 2)));
8742 case PSEUDO_DTOR_EXPR:
8743 return finish_pseudo_destructor_expr
8744 (RECUR (TREE_OPERAND (t, 0)),
8745 RECUR (TREE_OPERAND (t, 1)),
8746 RECUR (TREE_OPERAND (t, 2)));
8750 tree purpose, value, chain;
8752 if (t == void_list_node)
8755 purpose = TREE_PURPOSE (t);
8757 purpose = RECUR (purpose);
8758 value = TREE_VALUE (t);
8760 value = RECUR (value);
8761 chain = TREE_CHAIN (t);
8762 if (chain && chain != void_type_node)
8763 chain = RECUR (chain);
8764 if (purpose == TREE_PURPOSE (t)
8765 && value == TREE_VALUE (t)
8766 && chain == TREE_CHAIN (t))
8768 return tree_cons (purpose, value, chain);
8776 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8777 args, complain, in_decl);
8778 /* Remember that there was a reference to this entity. */
8779 if (DECL_P (object))
8782 member = TREE_OPERAND (t, 1);
8783 if (BASELINK_P (member))
8784 member = tsubst_baselink (member,
8785 non_reference (TREE_TYPE (object)),
8786 args, complain, in_decl);
8788 member = tsubst_copy (member, args, complain, in_decl);
8790 if (member == error_mark_node)
8791 return error_mark_node;
8792 else if (!CLASS_TYPE_P (TREE_TYPE (object)))
8794 if (TREE_CODE (member) == BIT_NOT_EXPR)
8795 return finish_pseudo_destructor_expr (object,
8797 TREE_TYPE (object));
8798 else if (TREE_CODE (member) == SCOPE_REF
8799 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8800 return finish_pseudo_destructor_expr (object,
8802 TREE_TYPE (object));
8804 else if (TREE_CODE (member) == SCOPE_REF
8805 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8810 /* Lookup the template functions now that we know what the
8812 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8813 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8814 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8815 /*is_type_p=*/false,
8816 /*complain=*/false);
8817 if (BASELINK_P (member))
8819 BASELINK_FUNCTIONS (member)
8820 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8822 member = (adjust_result_of_qualified_name_lookup
8823 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8824 TREE_TYPE (object)));
8828 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8830 return error_mark_node;
8833 else if (TREE_CODE (member) == SCOPE_REF
8834 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8835 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8837 if (complain & tf_error)
8839 if (TYPE_P (TREE_OPERAND (member, 0)))
8840 error ("%qT is not a class or namespace",
8841 TREE_OPERAND (member, 0));
8843 error ("%qD is not a class or namespace",
8844 TREE_OPERAND (member, 0));
8846 return error_mark_node;
8848 else if (TREE_CODE (member) == FIELD_DECL)
8849 return finish_non_static_data_member (member, object, NULL_TREE);
8851 return finish_class_member_access_expr (object, member);
8856 (RECUR (TREE_OPERAND (t, 0)));
8860 VEC(constructor_elt,gc) *n;
8861 constructor_elt *ce;
8862 unsigned HOST_WIDE_INT idx;
8864 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8865 bool process_index_p;
8867 /* digest_init will do the wrong thing if we let it. */
8868 if (type && TYPE_PTRMEMFUNC_P (type))
8871 /* We do not want to process the index of aggregate
8872 initializers as they are identifier nodes which will be
8873 looked up by digest_init. */
8874 process_index_p = !(type && IS_AGGR_TYPE (type));
8876 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
8877 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
8879 if (ce->index && process_index_p)
8880 ce->index = RECUR (ce->index);
8881 ce->value = RECUR (ce->value);
8884 r = build_constructor (NULL_TREE, n);
8885 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8888 return digest_init (type, r);
8894 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8895 if (TYPE_P (operand_0))
8896 return get_typeid (operand_0);
8897 return build_typeid (operand_0);
8907 tree r = tsubst_copy (t, args, complain, in_decl);
8909 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
8910 /* If the original type was a reference, we'll be wrapped in
8911 the appropriate INDIRECT_REF. */
8912 r = convert_from_reference (r);
8917 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8918 tsubst_copy (TREE_TYPE (t), args, complain,
8922 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8926 tree old_stmt_expr = cur_stmt_expr;
8927 tree stmt_expr = begin_stmt_expr ();
8929 cur_stmt_expr = stmt_expr;
8930 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8931 stmt_expr = finish_stmt_expr (stmt_expr, false);
8932 cur_stmt_expr = old_stmt_expr;
8938 t = tsubst_copy (t, args, complain, in_decl);
8939 /* As in finish_id_expression, we resolve enumeration constants
8940 to their underlying values. */
8941 if (TREE_CODE (t) == CONST_DECL)
8942 return DECL_INITIAL (t);
8946 /* Handle Objective-C++ constructs, if appropriate. */
8949 = objcp_tsubst_copy_and_build (t, args, complain,
8950 in_decl, /*function_p=*/false);
8954 return tsubst_copy (t, args, complain, in_decl);
8960 /* Verify that the instantiated ARGS are valid. For type arguments,
8961 make sure that the type's linkage is ok. For non-type arguments,
8962 make sure they are constants if they are integral or enumerations.
8963 Emit an error under control of COMPLAIN, and return TRUE on error. */
8966 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8968 int ix, len = DECL_NTPARMS (tmpl);
8969 bool result = false;
8971 for (ix = 0; ix != len; ix++)
8973 tree t = TREE_VEC_ELT (args, ix);
8977 /* [basic.link]: A name with no linkage (notably, the name
8978 of a class or enumeration declared in a local scope)
8979 shall not be used to declare an entity with linkage.
8980 This implies that names with no linkage cannot be used as
8981 template arguments. */
8982 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8986 /* DR 488 makes use of a type with no linkage causes
8987 type deduction to fail. */
8988 if (complain & tf_error)
8990 if (TYPE_ANONYMOUS_P (nt))
8991 error ("%qT is/uses anonymous type", t);
8993 error ("%qT uses local type %qT", t, nt);
8997 /* In order to avoid all sorts of complications, we do not
8998 allow variably-modified types as template arguments. */
8999 else if (variably_modified_type_p (t, NULL_TREE))
9001 if (complain & tf_error)
9002 error ("%qT is a variably modified type", t);
9006 /* A non-type argument of integral or enumerated type must be a
9008 else if (TREE_TYPE (t)
9009 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
9010 && !TREE_CONSTANT (t))
9012 if (complain & tf_error)
9013 error ("integral expression %qE is not constant", t);
9017 if (result && (complain & tf_error))
9018 error (" trying to instantiate %qD", tmpl);
9022 /* Instantiate the indicated variable or function template TMPL with
9023 the template arguments in TARG_PTR. */
9026 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
9032 if (tmpl == error_mark_node)
9033 return error_mark_node;
9035 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
9037 /* If this function is a clone, handle it specially. */
9038 if (DECL_CLONED_FUNCTION_P (tmpl))
9043 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
9045 if (spec == error_mark_node)
9046 return error_mark_node;
9048 /* Look for the clone. */
9049 FOR_EACH_CLONE (clone, spec)
9050 if (DECL_NAME (clone) == DECL_NAME (tmpl))
9052 /* We should always have found the clone by now. */
9057 /* Check to see if we already have this specialization. */
9058 spec = retrieve_specialization (tmpl, targ_ptr,
9059 /*class_specializations_p=*/false);
9060 if (spec != NULL_TREE)
9063 gen_tmpl = most_general_template (tmpl);
9064 if (tmpl != gen_tmpl)
9066 /* The TMPL is a partial instantiation. To get a full set of
9067 arguments we must add the arguments used to perform the
9068 partial instantiation. */
9069 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9072 /* Check to see if we already have this specialization. */
9073 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9074 /*class_specializations_p=*/false);
9075 if (spec != NULL_TREE)
9079 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9081 return error_mark_node;
9083 /* We are building a FUNCTION_DECL, during which the access of its
9084 parameters and return types have to be checked. However this
9085 FUNCTION_DECL which is the desired context for access checking
9086 is not built yet. We solve this chicken-and-egg problem by
9087 deferring all checks until we have the FUNCTION_DECL. */
9088 push_deferring_access_checks (dk_deferred);
9090 /* Substitute template parameters. */
9091 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9092 targ_ptr, complain, gen_tmpl);
9094 /* Now we know the specialization, compute access previously
9096 push_access_scope (fndecl);
9097 perform_deferred_access_checks ();
9098 pop_access_scope (fndecl);
9099 pop_deferring_access_checks ();
9101 /* The DECL_TI_TEMPLATE should always be the immediate parent
9102 template, not the most general template. */
9103 DECL_TI_TEMPLATE (fndecl) = tmpl;
9105 /* If we've just instantiated the main entry point for a function,
9106 instantiate all the alternate entry points as well. We do this
9107 by cloning the instantiation of the main entry point, not by
9108 instantiating the template clones. */
9109 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9110 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9115 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9116 arguments that are being used when calling it. TARGS is a vector
9117 into which the deduced template arguments are placed.
9119 Return zero for success, 2 for an incomplete match that doesn't resolve
9120 all the types, and 1 for complete failure. An error message will be
9121 printed only for an incomplete match.
9123 If FN is a conversion operator, or we are trying to produce a specific
9124 specialization, RETURN_TYPE is the return type desired.
9126 The EXPLICIT_TARGS are explicit template arguments provided via a
9129 The parameter STRICT is one of:
9132 We are deducing arguments for a function call, as in
9136 We are deducing arguments for a conversion function, as in
9140 We are deducing arguments when doing an explicit instantiation
9141 as in [temp.explicit], when determining an explicit specialization
9142 as in [temp.expl.spec], or when taking the address of a function
9143 template, as in [temp.deduct.funcaddr]. */
9146 fn_type_unification (tree fn,
9147 tree explicit_targs,
9151 unification_kind_t strict,
9158 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9160 fntype = TREE_TYPE (fn);
9165 The specified template arguments must match the template
9166 parameters in kind (i.e., type, nontype, template), and there
9167 must not be more arguments than there are parameters;
9168 otherwise type deduction fails.
9170 Nontype arguments must match the types of the corresponding
9171 nontype template parameters, or must be convertible to the
9172 types of the corresponding nontype parameters as specified in
9173 _temp.arg.nontype_, otherwise type deduction fails.
9175 All references in the function type of the function template
9176 to the corresponding template parameters are replaced by the
9177 specified template argument values. If a substitution in a
9178 template parameter or in the function type of the function
9179 template results in an invalid type, type deduction fails. */
9181 tree converted_args;
9184 if (explicit_targs == error_mark_node)
9188 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9189 explicit_targs, NULL_TREE, tf_none,
9190 /*require_all_arguments=*/0));
9191 if (converted_args == error_mark_node)
9194 /* Substitute the explicit args into the function type. This is
9195 necessary so that, for instance, explicitly declared function
9196 arguments can match null pointed constants. If we were given
9197 an incomplete set of explicit args, we must not do semantic
9198 processing during substitution as we could create partial
9200 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9201 processing_template_decl += incomplete;
9202 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9203 processing_template_decl -= incomplete;
9205 if (fntype == error_mark_node)
9208 /* Place the explicitly specified arguments in TARGS. */
9209 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9210 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9213 parms = TYPE_ARG_TYPES (fntype);
9214 /* Never do unification on the 'this' parameter. */
9215 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9216 parms = TREE_CHAIN (parms);
9220 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9221 args = tree_cons (NULL_TREE, return_type, args);
9224 /* We allow incomplete unification without an error message here
9225 because the standard doesn't seem to explicitly prohibit it. Our
9226 callers must be ready to deal with unification failures in any
9228 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9229 targs, parms, args, /*subr=*/0,
9233 /* All is well so far. Now, check:
9237 When all template arguments have been deduced, all uses of
9238 template parameters in nondeduced contexts are replaced with
9239 the corresponding deduced argument values. If the
9240 substitution results in an invalid type, as described above,
9241 type deduction fails. */
9242 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9249 /* Adjust types before performing type deduction, as described in
9250 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9251 sections are symmetric. PARM is the type of a function parameter
9252 or the return type of the conversion function. ARG is the type of
9253 the argument passed to the call, or the type of the value
9254 initialized with the result of the conversion function. */
9257 maybe_adjust_types_for_deduction (unification_kind_t strict,
9270 /* Swap PARM and ARG throughout the remainder of this
9271 function; the handling is precisely symmetric since PARM
9272 will initialize ARG rather than vice versa. */
9280 /* There is nothing to do in this case. */
9287 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9289 /* [temp.deduct.call]
9291 If P is not a reference type:
9293 --If A is an array type, the pointer type produced by the
9294 array-to-pointer standard conversion (_conv.array_) is
9295 used in place of A for type deduction; otherwise,
9297 --If A is a function type, the pointer type produced by
9298 the function-to-pointer standard conversion
9299 (_conv.func_) is used in place of A for type deduction;
9302 --If A is a cv-qualified type, the top level
9303 cv-qualifiers of A's type are ignored for type
9305 if (TREE_CODE (*arg) == ARRAY_TYPE)
9306 *arg = build_pointer_type (TREE_TYPE (*arg));
9307 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9308 *arg = build_pointer_type (*arg);
9310 *arg = TYPE_MAIN_VARIANT (*arg);
9313 /* [temp.deduct.call]
9315 If P is a cv-qualified type, the top level cv-qualifiers
9316 of P's type are ignored for type deduction. If P is a
9317 reference type, the type referred to by P is used for
9319 *parm = TYPE_MAIN_VARIANT (*parm);
9320 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9322 *parm = TREE_TYPE (*parm);
9323 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9326 /* DR 322. For conversion deduction, remove a reference type on parm
9327 too (which has been swapped into ARG). */
9328 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9329 *arg = TREE_TYPE (*arg);
9334 /* Most parms like fn_type_unification.
9336 If SUBR is 1, we're being called recursively (to unify the
9337 arguments of a function or method parameter of a function
9341 type_unification_real (tree tparms,
9346 unification_kind_t strict,
9351 int ntparms = TREE_VEC_LENGTH (tparms);
9353 int saw_undeduced = 0;
9356 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9357 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9358 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9359 gcc_assert (ntparms > 0);
9364 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9365 | UNIFY_ALLOW_DERIVED);
9369 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9373 sub_strict = UNIFY_ALLOW_NONE;
9384 while (parms && parms != void_list_node
9385 && args && args != void_list_node)
9387 parm = TREE_VALUE (parms);
9388 parms = TREE_CHAIN (parms);
9389 arg = TREE_VALUE (args);
9390 args = TREE_CHAIN (args);
9392 if (arg == error_mark_node)
9394 if (arg == unknown_type_node)
9395 /* We can't deduce anything from this, but we might get all the
9396 template args from other function args. */
9399 /* Conversions will be performed on a function argument that
9400 corresponds with a function parameter that contains only
9401 non-deducible template parameters and explicitly specified
9402 template parameters. */
9403 if (!uses_template_parms (parm))
9408 type = TREE_TYPE (arg);
9412 if (same_type_p (parm, type))
9414 if (strict != DEDUCE_EXACT
9415 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
9424 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9425 if (type_unknown_p (arg))
9427 /* [temp.deduct.type] A template-argument can be deduced from
9428 a pointer to function or pointer to member function
9429 argument if the set of overloaded functions does not
9430 contain function templates and at most one of a set of
9431 overloaded functions provides a unique match. */
9433 if (resolve_overloaded_unification
9434 (tparms, targs, parm, arg, strict, sub_strict)
9439 arg = TREE_TYPE (arg);
9440 if (arg == error_mark_node)
9445 int arg_strict = sub_strict;
9448 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9450 if (unify (tparms, targs, parm, arg, arg_strict))
9455 /* Fail if we've reached the end of the parm list, and more args
9456 are present, and the parm list isn't variadic. */
9457 if (args && args != void_list_node && parms == void_list_node)
9459 /* Fail if parms are left and they don't have default values. */
9460 if (parms && parms != void_list_node
9461 && TREE_PURPOSE (parms) == NULL_TREE)
9465 for (i = 0; i < ntparms; i++)
9466 if (!TREE_VEC_ELT (targs, i))
9468 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9470 /* If this is an undeduced nontype parameter that depends on
9471 a type parameter, try another pass; its type may have been
9472 deduced from a later argument than the one from which
9473 this parameter can be deduced. */
9474 if (TREE_CODE (tparm) == PARM_DECL
9475 && uses_template_parms (TREE_TYPE (tparm))
9476 && !saw_undeduced++)
9485 /* Subroutine of type_unification_real. Args are like the variables at the
9486 call site. ARG is an overloaded function (or template-id); we try
9487 deducing template args from each of the overloads, and if only one
9488 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9491 resolve_overloaded_unification (tree tparms,
9495 unification_kind_t strict,
9498 tree tempargs = copy_node (targs);
9502 if (TREE_CODE (arg) == ADDR_EXPR)
9504 arg = TREE_OPERAND (arg, 0);
9510 if (TREE_CODE (arg) == COMPONENT_REF)
9511 /* Handle `&x' where `x' is some static or non-static member
9513 arg = TREE_OPERAND (arg, 1);
9515 if (TREE_CODE (arg) == OFFSET_REF)
9516 arg = TREE_OPERAND (arg, 1);
9518 /* Strip baselink information. */
9519 if (BASELINK_P (arg))
9520 arg = BASELINK_FUNCTIONS (arg);
9522 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9524 /* If we got some explicit template args, we need to plug them into
9525 the affected templates before we try to unify, in case the
9526 explicit args will completely resolve the templates in question. */
9528 tree expl_subargs = TREE_OPERAND (arg, 1);
9529 arg = TREE_OPERAND (arg, 0);
9531 for (; arg; arg = OVL_NEXT (arg))
9533 tree fn = OVL_CURRENT (arg);
9536 if (TREE_CODE (fn) != TEMPLATE_DECL)
9539 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
9540 expl_subargs, /*check_ret=*/false);
9543 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9544 good += try_one_overload (tparms, targs, tempargs, parm,
9545 elem, strict, sub_strict, addr_p);
9551 gcc_assert (TREE_CODE (arg) == OVERLOAD
9552 || TREE_CODE (arg) == FUNCTION_DECL);
9554 for (; arg; arg = OVL_NEXT (arg))
9555 good += try_one_overload (tparms, targs, tempargs, parm,
9556 TREE_TYPE (OVL_CURRENT (arg)),
9557 strict, sub_strict, addr_p);
9560 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9561 to function or pointer to member function argument if the set of
9562 overloaded functions does not contain function templates and at most
9563 one of a set of overloaded functions provides a unique match.
9565 So if we found multiple possibilities, we return success but don't
9570 int i = TREE_VEC_LENGTH (targs);
9572 if (TREE_VEC_ELT (tempargs, i))
9573 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9581 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9582 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9583 different overloads deduce different arguments for a given parm.
9584 ADDR_P is true if the expression for which deduction is being
9585 performed was of the form "& fn" rather than simply "fn".
9587 Returns 1 on success. */
9590 try_one_overload (tree tparms,
9595 unification_kind_t strict,
9603 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9604 to function or pointer to member function argument if the set of
9605 overloaded functions does not contain function templates and at most
9606 one of a set of overloaded functions provides a unique match.
9608 So if this is a template, just return success. */
9610 if (uses_template_parms (arg))
9613 if (TREE_CODE (arg) == METHOD_TYPE)
9614 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9616 arg = build_pointer_type (arg);
9618 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9620 /* We don't copy orig_targs for this because if we have already deduced
9621 some template args from previous args, unify would complain when we
9622 try to deduce a template parameter for the same argument, even though
9623 there isn't really a conflict. */
9624 nargs = TREE_VEC_LENGTH (targs);
9625 tempargs = make_tree_vec (nargs);
9627 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9630 /* First make sure we didn't deduce anything that conflicts with
9631 explicitly specified args. */
9632 for (i = nargs; i--; )
9634 tree elt = TREE_VEC_ELT (tempargs, i);
9635 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9639 else if (uses_template_parms (elt))
9640 /* Since we're unifying against ourselves, we will fill in
9641 template args used in the function parm list with our own
9642 template parms. Discard them. */
9643 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9644 else if (oldelt && !template_args_equal (oldelt, elt))
9648 for (i = nargs; i--; )
9650 tree elt = TREE_VEC_ELT (tempargs, i);
9653 TREE_VEC_ELT (targs, i) = elt;
9659 /* Verify that nondeduce template argument agrees with the type
9660 obtained from argument deduction. Return nonzero if the
9665 struct A { typedef int X; };
9666 template <class T, class U> struct C {};
9667 template <class T> struct C<T, typename T::X> {};
9669 Then with the instantiation `C<A, int>', we can deduce that
9670 `T' is `A' but unify () does not check whether `typename T::X'
9671 is `int'. This function ensure that they agree.
9673 TARGS, PARMS are the same as the arguments of unify.
9674 ARGS contains template arguments from all levels. */
9677 verify_class_unification (tree targs, tree parms, tree args)
9679 parms = tsubst (parms, add_outermost_template_args (args, targs),
9680 tf_none, NULL_TREE);
9681 if (parms == error_mark_node)
9684 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9687 /* PARM is a template class (perhaps with unbound template
9688 parameters). ARG is a fully instantiated type. If ARG can be
9689 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9690 TARGS are as for unify. */
9693 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9697 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9698 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9699 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9702 /* We need to make a new template argument vector for the call to
9703 unify. If we used TARGS, we'd clutter it up with the result of
9704 the attempted unification, even if this class didn't work out.
9705 We also don't want to commit ourselves to all the unifications
9706 we've already done, since unification is supposed to be done on
9707 an argument-by-argument basis. In other words, consider the
9708 following pathological case:
9710 template <int I, int J, int K>
9713 template <int I, int J>
9714 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9716 template <int I, int J, int K>
9717 void f(S<I, J, K>, S<I, I, I>);
9726 Now, by the time we consider the unification involving `s2', we
9727 already know that we must have `f<0, 0, 0>'. But, even though
9728 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9729 because there are two ways to unify base classes of S<0, 1, 2>
9730 with S<I, I, I>. If we kept the already deduced knowledge, we
9731 would reject the possibility I=1. */
9732 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9734 /* If unification failed, we're done. */
9735 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9736 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9742 /* Given a template type PARM and a class type ARG, find the unique
9743 base type in ARG that is an instance of PARM. We do not examine
9744 ARG itself; only its base-classes. If there is not exactly one
9745 appropriate base class, return NULL_TREE. PARM may be the type of
9746 a partial specialization, as well as a plain template type. Used
9750 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9752 tree rval = NULL_TREE;
9755 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9757 binfo = TYPE_BINFO (complete_type (arg));
9759 /* The type could not be completed. */
9762 /* Walk in inheritance graph order. The search order is not
9763 important, and this avoids multiple walks of virtual bases. */
9764 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9766 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9770 /* If there is more than one satisfactory baseclass, then:
9774 If they yield more than one possible deduced A, the type
9778 if (rval && !same_type_p (r, rval))
9788 /* Returns the level of DECL, which declares a template parameter. */
9791 template_decl_level (tree decl)
9793 switch (TREE_CODE (decl))
9797 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9800 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9808 /* Decide whether ARG can be unified with PARM, considering only the
9809 cv-qualifiers of each type, given STRICT as documented for unify.
9810 Returns nonzero iff the unification is OK on that basis. */
9813 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9815 int arg_quals = cp_type_quals (arg);
9816 int parm_quals = cp_type_quals (parm);
9818 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9819 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9821 /* Although a CVR qualifier is ignored when being applied to a
9822 substituted template parameter ([8.3.2]/1 for example), that
9823 does not apply during deduction [14.8.2.4]/1, (even though
9824 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9825 this). Except when we're allowing additional CV qualifiers
9826 at the outer level [14.8.2.1]/3,1st bullet. */
9827 if ((TREE_CODE (arg) == REFERENCE_TYPE
9828 || TREE_CODE (arg) == FUNCTION_TYPE
9829 || TREE_CODE (arg) == METHOD_TYPE)
9830 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9833 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9834 && (parm_quals & TYPE_QUAL_RESTRICT))
9838 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9839 && (arg_quals & parm_quals) != parm_quals)
9842 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9843 && (parm_quals & arg_quals) != arg_quals)
9849 /* Takes parameters as for type_unification. Returns 0 if the
9850 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9851 bitwise or of the following flags:
9854 Require an exact match between PARM and ARG.
9855 UNIFY_ALLOW_MORE_CV_QUAL:
9856 Allow the deduced ARG to be more cv-qualified (by qualification
9857 conversion) than ARG.
9858 UNIFY_ALLOW_LESS_CV_QUAL:
9859 Allow the deduced ARG to be less cv-qualified than ARG.
9860 UNIFY_ALLOW_DERIVED:
9861 Allow the deduced ARG to be a template base class of ARG,
9862 or a pointer to a template base class of the type pointed to by
9864 UNIFY_ALLOW_INTEGER:
9865 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9866 case for more information.
9867 UNIFY_ALLOW_OUTER_LEVEL:
9868 This is the outermost level of a deduction. Used to determine validity
9869 of qualification conversions. A valid qualification conversion must
9870 have const qualified pointers leading up to the inner type which
9871 requires additional CV quals, except at the outer level, where const
9872 is not required [conv.qual]. It would be normal to set this flag in
9873 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9874 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9875 This is the outermost level of a deduction, and PARM can be more CV
9876 qualified at this point.
9877 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9878 This is the outermost level of a deduction, and PARM can be less CV
9879 qualified at this point. */
9882 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9887 int strict_in = strict;
9889 /* I don't think this will do the right thing with respect to types.
9890 But the only case I've seen it in so far has been array bounds, where
9891 signedness is the only information lost, and I think that will be
9893 while (TREE_CODE (parm) == NOP_EXPR)
9894 parm = TREE_OPERAND (parm, 0);
9896 if (arg == error_mark_node)
9898 if (arg == unknown_type_node)
9899 /* We can't deduce anything from this, but we might get all the
9900 template args from other function args. */
9903 /* If PARM uses template parameters, then we can't bail out here,
9904 even if ARG == PARM, since we won't record unifications for the
9905 template parameters. We might need them if we're trying to
9906 figure out which of two things is more specialized. */
9907 if (arg == parm && !uses_template_parms (parm))
9910 /* Immediately reject some pairs that won't unify because of
9911 cv-qualification mismatches. */
9912 if (TREE_CODE (arg) == TREE_CODE (parm)
9914 /* It is the elements of the array which hold the cv quals of an array
9915 type, and the elements might be template type parms. We'll check
9917 && TREE_CODE (arg) != ARRAY_TYPE
9918 /* We check the cv-qualifiers when unifying with template type
9919 parameters below. We want to allow ARG `const T' to unify with
9920 PARM `T' for example, when computing which of two templates
9921 is more specialized, for example. */
9922 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9923 && !check_cv_quals_for_unify (strict_in, arg, parm))
9926 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9927 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9928 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9929 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9930 strict &= ~UNIFY_ALLOW_DERIVED;
9931 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9932 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9934 switch (TREE_CODE (parm))
9938 case UNBOUND_CLASS_TEMPLATE:
9939 /* In a type which contains a nested-name-specifier, template
9940 argument values cannot be deduced for template parameters used
9941 within the nested-name-specifier. */
9944 case TEMPLATE_TYPE_PARM:
9945 case TEMPLATE_TEMPLATE_PARM:
9946 case BOUND_TEMPLATE_TEMPLATE_PARM:
9947 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9949 if (TEMPLATE_TYPE_LEVEL (parm)
9950 != template_decl_level (tparm))
9951 /* The PARM is not one we're trying to unify. Just check
9952 to see if it matches ARG. */
9953 return (TREE_CODE (arg) == TREE_CODE (parm)
9954 && same_type_p (parm, arg)) ? 0 : 1;
9955 idx = TEMPLATE_TYPE_IDX (parm);
9956 targ = TREE_VEC_ELT (targs, idx);
9957 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9959 /* Check for mixed types and values. */
9960 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9961 && TREE_CODE (tparm) != TYPE_DECL)
9962 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9963 && TREE_CODE (tparm) != TEMPLATE_DECL))
9966 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9968 /* ARG must be constructed from a template class or a template
9969 template parameter. */
9970 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9971 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9975 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9976 tree parmvec = TYPE_TI_ARGS (parm);
9977 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9979 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9982 /* The parameter and argument roles have to be switched here
9983 in order to handle default arguments properly. For example,
9984 template<template <class> class TT> void f(TT<int>)
9985 should be able to accept vector<int> which comes from
9986 template <class T, class Allocator = allocator>
9989 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9993 /* Deduce arguments T, i from TT<T> or TT<i>.
9994 We check each element of PARMVEC and ARGVEC individually
9995 rather than the whole TREE_VEC since they can have
9996 different number of elements. */
9998 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
10000 if (unify (tparms, targs,
10001 TREE_VEC_ELT (parmvec, i),
10002 TREE_VEC_ELT (argvec, i),
10007 arg = TYPE_TI_TEMPLATE (arg);
10009 /* Fall through to deduce template name. */
10012 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10013 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10015 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
10017 /* Simple cases: Value already set, does match or doesn't. */
10018 if (targ != NULL_TREE && template_args_equal (targ, arg))
10025 /* If PARM is `const T' and ARG is only `int', we don't have
10026 a match unless we are allowing additional qualification.
10027 If ARG is `const int' and PARM is just `T' that's OK;
10028 that binds `const int' to `T'. */
10029 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10033 /* Consider the case where ARG is `const volatile int' and
10034 PARM is `const T'. Then, T should be `volatile int'. */
10035 arg = cp_build_qualified_type_real
10036 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10037 if (arg == error_mark_node)
10040 /* Simple cases: Value already set, does match or doesn't. */
10041 if (targ != NULL_TREE && same_type_p (targ, arg))
10046 /* Make sure that ARG is not a variable-sized array. (Note
10047 that were talking about variable-sized arrays (like
10048 `int[n]'), rather than arrays of unknown size (like
10049 `int[]').) We'll get very confused by such a type since
10050 the bound of the array will not be computable in an
10051 instantiation. Besides, such types are not allowed in
10052 ISO C++, so we can do as we please here. */
10053 if (variably_modified_type_p (arg, NULL_TREE))
10057 TREE_VEC_ELT (targs, idx) = arg;
10060 case TEMPLATE_PARM_INDEX:
10061 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10063 if (TEMPLATE_PARM_LEVEL (parm)
10064 != template_decl_level (tparm))
10065 /* The PARM is not one we're trying to unify. Just check
10066 to see if it matches ARG. */
10067 return !(TREE_CODE (arg) == TREE_CODE (parm)
10068 && cp_tree_equal (parm, arg));
10070 idx = TEMPLATE_PARM_IDX (parm);
10071 targ = TREE_VEC_ELT (targs, idx);
10074 return !cp_tree_equal (targ, arg);
10076 /* [temp.deduct.type] If, in the declaration of a function template
10077 with a non-type template-parameter, the non-type
10078 template-parameter is used in an expression in the function
10079 parameter-list and, if the corresponding template-argument is
10080 deduced, the template-argument type shall match the type of the
10081 template-parameter exactly, except that a template-argument
10082 deduced from an array bound may be of any integral type.
10083 The non-type parameter might use already deduced type parameters. */
10084 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10085 if (!TREE_TYPE (arg))
10086 /* Template-parameter dependent expression. Just accept it for now.
10087 It will later be processed in convert_template_argument. */
10089 else if (same_type_p (TREE_TYPE (arg), tparm))
10091 else if ((strict & UNIFY_ALLOW_INTEGER)
10092 && (TREE_CODE (tparm) == INTEGER_TYPE
10093 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10094 /* Convert the ARG to the type of PARM; the deduced non-type
10095 template argument must exactly match the types of the
10096 corresponding parameter. */
10097 arg = fold (build_nop (TREE_TYPE (parm), arg));
10098 else if (uses_template_parms (tparm))
10099 /* We haven't deduced the type of this parameter yet. Try again
10105 TREE_VEC_ELT (targs, idx) = arg;
10110 /* A pointer-to-member constant can be unified only with
10111 another constant. */
10112 if (TREE_CODE (arg) != PTRMEM_CST)
10115 /* Just unify the class member. It would be useless (and possibly
10116 wrong, depending on the strict flags) to unify also
10117 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10118 arg refer to the same variable, even if through different
10119 classes. For instance:
10121 struct A { int x; };
10124 Unification of &A::x and &B::x must succeed. */
10125 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10126 PTRMEM_CST_MEMBER (arg), strict);
10131 if (TREE_CODE (arg) != POINTER_TYPE)
10134 /* [temp.deduct.call]
10136 A can be another pointer or pointer to member type that can
10137 be converted to the deduced A via a qualification
10138 conversion (_conv.qual_).
10140 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10141 This will allow for additional cv-qualification of the
10142 pointed-to types if appropriate. */
10144 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10145 /* The derived-to-base conversion only persists through one
10146 level of pointers. */
10147 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10149 return unify (tparms, targs, TREE_TYPE (parm),
10150 TREE_TYPE (arg), strict);
10153 case REFERENCE_TYPE:
10154 if (TREE_CODE (arg) != REFERENCE_TYPE)
10156 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10157 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10160 if (TREE_CODE (arg) != ARRAY_TYPE)
10162 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10163 != (TYPE_DOMAIN (arg) == NULL_TREE))
10165 if (TYPE_DOMAIN (parm) != NULL_TREE)
10170 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10171 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10173 /* Our representation of array types uses "N - 1" as the
10174 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10175 not an integer constant. */
10176 if (TREE_CODE (parm_max) == MINUS_EXPR)
10178 arg_max = fold_build2 (PLUS_EXPR,
10181 TREE_OPERAND (parm_max, 1));
10182 parm_max = TREE_OPERAND (parm_max, 0);
10185 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10188 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10189 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10196 case ENUMERAL_TYPE:
10198 if (TREE_CODE (arg) != TREE_CODE (parm))
10201 /* We have already checked cv-qualification at the top of the
10203 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10206 /* As far as unification is concerned, this wins. Later checks
10207 will invalidate it if necessary. */
10210 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10211 /* Type INTEGER_CST can come from ordinary constant template args. */
10213 while (TREE_CODE (arg) == NOP_EXPR)
10214 arg = TREE_OPERAND (arg, 0);
10216 if (TREE_CODE (arg) != INTEGER_CST)
10218 return !tree_int_cst_equal (parm, arg);
10223 if (TREE_CODE (arg) != TREE_VEC)
10225 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10227 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10228 if (unify (tparms, targs,
10229 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10237 if (TREE_CODE (arg) != TREE_CODE (parm))
10240 if (TYPE_PTRMEMFUNC_P (parm))
10242 if (!TYPE_PTRMEMFUNC_P (arg))
10245 return unify (tparms, targs,
10246 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10247 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10251 if (CLASSTYPE_TEMPLATE_INFO (parm))
10253 tree t = NULL_TREE;
10255 if (strict_in & UNIFY_ALLOW_DERIVED)
10257 /* First, we try to unify the PARM and ARG directly. */
10258 t = try_class_unification (tparms, targs,
10263 /* Fallback to the special case allowed in
10264 [temp.deduct.call]:
10266 If P is a class, and P has the form
10267 template-id, then A can be a derived class of
10268 the deduced A. Likewise, if P is a pointer to
10269 a class of the form template-id, A can be a
10270 pointer to a derived class pointed to by the
10272 t = get_template_base (tparms, targs, parm, arg);
10278 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10279 && (CLASSTYPE_TI_TEMPLATE (parm)
10280 == CLASSTYPE_TI_TEMPLATE (arg)))
10281 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10282 Then, we should unify `int' and `U'. */
10285 /* There's no chance of unification succeeding. */
10288 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10289 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10291 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10296 case FUNCTION_TYPE:
10297 if (TREE_CODE (arg) != TREE_CODE (parm))
10300 /* CV qualifications for methods can never be deduced, they must
10301 match exactly. We need to check them explicitly here,
10302 because type_unification_real treats them as any other
10303 cvqualified parameter. */
10304 if (TREE_CODE (parm) == METHOD_TYPE
10305 && (!check_cv_quals_for_unify
10307 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
10308 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
10311 if (unify (tparms, targs, TREE_TYPE (parm),
10312 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10314 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10315 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
10319 /* Unify a pointer to member with a pointer to member function, which
10320 deduces the type of the member as a function type. */
10321 if (TYPE_PTRMEMFUNC_P (arg))
10325 cp_cv_quals cv_quals;
10327 /* Check top-level cv qualifiers */
10328 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
10331 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10332 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
10335 /* Determine the type of the function we are unifying against. */
10336 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
10338 build_function_type (TREE_TYPE (method_type),
10339 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
10341 /* Extract the cv-qualifiers of the member function from the
10342 implicit object parameter and place them on the function
10343 type to be restored later. */
10345 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
10346 fntype = build_qualified_type (fntype, cv_quals);
10347 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
10350 if (TREE_CODE (arg) != OFFSET_TYPE)
10352 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10353 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10355 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10359 if (DECL_TEMPLATE_PARM_P (parm))
10360 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10361 if (arg != integral_constant_value (parm))
10366 case TEMPLATE_DECL:
10367 /* Matched cases are handled by the ARG == PARM test above. */
10371 gcc_assert (EXPR_P (parm));
10373 /* We must be looking at an expression. This can happen with
10377 void foo(S<I>, S<I + 2>);
10379 This is a "nondeduced context":
10383 The nondeduced contexts are:
10385 --A type that is a template-id in which one or more of
10386 the template-arguments is an expression that references
10387 a template-parameter.
10389 In these cases, we assume deduction succeeded, but don't
10390 actually infer any unifications. */
10392 if (!uses_template_parms (parm)
10393 && !template_args_equal (parm, arg))
10400 /* Note that DECL can be defined in this translation unit, if
10404 mark_definable (tree decl)
10407 DECL_NOT_REALLY_EXTERN (decl) = 1;
10408 FOR_EACH_CLONE (clone, decl)
10409 DECL_NOT_REALLY_EXTERN (clone) = 1;
10412 /* Called if RESULT is explicitly instantiated, or is a member of an
10413 explicitly instantiated class. */
10416 mark_decl_instantiated (tree result, int extern_p)
10418 SET_DECL_EXPLICIT_INSTANTIATION (result);
10420 /* If this entity has already been written out, it's too late to
10421 make any modifications. */
10422 if (TREE_ASM_WRITTEN (result))
10425 if (TREE_CODE (result) != FUNCTION_DECL)
10426 /* The TREE_PUBLIC flag for function declarations will have been
10427 set correctly by tsubst. */
10428 TREE_PUBLIC (result) = 1;
10430 /* This might have been set by an earlier implicit instantiation. */
10431 DECL_COMDAT (result) = 0;
10434 DECL_NOT_REALLY_EXTERN (result) = 0;
10437 mark_definable (result);
10438 /* Always make artificials weak. */
10439 if (DECL_ARTIFICIAL (result) && flag_weak)
10440 comdat_linkage (result);
10441 /* For WIN32 we also want to put explicit instantiations in
10442 linkonce sections. */
10443 else if (TREE_PUBLIC (result))
10444 maybe_make_one_only (result);
10447 /* If EXTERN_P, then this function will not be emitted -- unless
10448 followed by an explicit instantiation, at which point its linkage
10449 will be adjusted. If !EXTERN_P, then this function will be
10450 emitted here. In neither circumstance do we want
10451 import_export_decl to adjust the linkage. */
10452 DECL_INTERFACE_KNOWN (result) = 1;
10455 /* Given two function templates PAT1 and PAT2, return:
10457 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10458 -1 if PAT2 is more specialized than PAT1.
10459 0 if neither is more specialized.
10461 LEN indicates the number of parameters we should consider
10462 (defaulted parameters should not be considered).
10464 The 1998 std underspecified function template partial ordering, and
10465 DR214 addresses the issue. We take pairs of arguments, one from
10466 each of the templates, and deduce them against each other. One of
10467 the templates will be more specialized if all the *other*
10468 template's arguments deduce against its arguments and at least one
10469 of its arguments *does* *not* deduce against the other template's
10470 corresponding argument. Deduction is done as for class templates.
10471 The arguments used in deduction have reference and top level cv
10472 qualifiers removed. Iff both arguments were originally reference
10473 types *and* deduction succeeds in both directions, the template
10474 with the more cv-qualified argument wins for that pairing (if
10475 neither is more cv-qualified, they both are equal). Unlike regular
10476 deduction, after all the arguments have been deduced in this way,
10477 we do *not* verify the deduced template argument values can be
10478 substituted into non-deduced contexts, nor do we have to verify
10479 that all template arguments have been deduced. */
10482 more_specialized_fn (tree pat1, tree pat2, int len)
10484 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
10485 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
10486 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
10487 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
10488 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
10489 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
10490 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
10491 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
10495 /* If only one is a member function, they are unordered. */
10496 if (DECL_FUNCTION_MEMBER_P (decl1) != DECL_FUNCTION_MEMBER_P (decl2))
10499 /* Don't consider 'this' parameter. */
10500 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
10501 args1 = TREE_CHAIN (args1);
10502 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
10503 args2 = TREE_CHAIN (args2);
10505 /* If only one is a conversion operator, they are unordered. */
10506 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
10509 /* Consider the return type for a conversion function */
10510 if (DECL_CONV_FN_P (decl1))
10512 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
10513 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
10517 processing_template_decl++;
10521 tree arg1 = TREE_VALUE (args1);
10522 tree arg2 = TREE_VALUE (args2);
10523 int deduce1, deduce2;
10527 if (TREE_CODE (arg1) == REFERENCE_TYPE)
10529 arg1 = TREE_TYPE (arg1);
10530 quals1 = cp_type_quals (arg1);
10533 if (TREE_CODE (arg2) == REFERENCE_TYPE)
10535 arg2 = TREE_TYPE (arg2);
10536 quals2 = cp_type_quals (arg2);
10539 if ((quals1 < 0) != (quals2 < 0))
10541 /* Only of the args is a reference, see if we should apply
10542 array/function pointer decay to it. This is not part of
10543 DR214, but is, IMHO, consistent with the deduction rules
10544 for the function call itself, and with our earlier
10545 implementation of the underspecified partial ordering
10546 rules. (nathan). */
10549 switch (TREE_CODE (arg1))
10552 arg1 = TREE_TYPE (arg1);
10554 case FUNCTION_TYPE:
10555 arg1 = build_pointer_type (arg1);
10564 switch (TREE_CODE (arg2))
10567 arg2 = TREE_TYPE (arg2);
10569 case FUNCTION_TYPE:
10570 arg2 = build_pointer_type (arg2);
10579 arg1 = TYPE_MAIN_VARIANT (arg1);
10580 arg2 = TYPE_MAIN_VARIANT (arg2);
10582 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
10583 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
10589 if (better1 < 0 && better2 < 0)
10590 /* We've failed to deduce something in either direction.
10591 These must be unordered. */
10594 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
10596 /* Deduces in both directions, see if quals can
10597 disambiguate. Pretend the worse one failed to deduce. */
10598 if ((quals1 & quals2) == quals2)
10600 if ((quals1 & quals2) == quals1)
10603 if (deduce1 && !deduce2 && !better2)
10605 if (deduce2 && !deduce1 && !better1)
10608 args1 = TREE_CHAIN (args1);
10609 args2 = TREE_CHAIN (args2);
10612 processing_template_decl--;
10614 return (better1 > 0) - (better2 > 0);
10617 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10619 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10620 -1 if PAT2 is more specialized than PAT1.
10621 0 if neither is more specialized.
10623 FULL_ARGS is the full set of template arguments that triggers this
10624 partial ordering. */
10627 more_specialized_class (tree pat1, tree pat2, tree full_args)
10632 /* Just like what happens for functions, if we are ordering between
10633 different class template specializations, we may encounter dependent
10634 types in the arguments, and we need our dependency check functions
10635 to behave correctly. */
10636 ++processing_template_decl;
10637 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10638 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10642 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10643 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10646 --processing_template_decl;
10651 /* Return the template arguments that will produce the function signature
10652 DECL from the function template FN, with the explicit template
10653 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
10654 also match. Return NULL_TREE if no satisfactory arguments could be
10658 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
10660 int ntparms = DECL_NTPARMS (fn);
10661 tree targs = make_tree_vec (ntparms);
10663 tree decl_arg_types;
10665 /* Substitute the explicit template arguments into the type of DECL.
10666 The call to fn_type_unification will handle substitution into the
10668 decl_type = TREE_TYPE (decl);
10669 if (explicit_args && uses_template_parms (decl_type))
10672 tree converted_args;
10674 if (DECL_TEMPLATE_INFO (decl))
10675 tmpl = DECL_TI_TEMPLATE (decl);
10677 /* We can get here for some invalid specializations. */
10681 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10682 explicit_args, NULL_TREE,
10683 tf_none, /*require_all_arguments=*/0));
10684 if (converted_args == error_mark_node)
10687 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10688 if (decl_type == error_mark_node)
10692 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10693 /* Never do unification on the 'this' parameter. */
10694 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10695 decl_arg_types = TREE_CHAIN (decl_arg_types);
10697 if (fn_type_unification (fn, explicit_args, targs,
10699 (check_rettype || DECL_CONV_FN_P (fn)
10700 ? TREE_TYPE (decl_type) : NULL_TREE),
10701 DEDUCE_EXACT, LOOKUP_NORMAL))
10707 /* Return the innermost template arguments that, when applied to a
10708 template specialization whose innermost template parameters are
10709 TPARMS, and whose specialization arguments are PARMS, yield the
10712 For example, suppose we have:
10714 template <class T, class U> struct S {};
10715 template <class T> struct S<T*, int> {};
10717 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10718 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10719 int}. The resulting vector will be {double}, indicating that `T'
10720 is bound to `double'. */
10723 get_class_bindings (tree tparms, tree parms, tree args)
10725 int i, ntparms = TREE_VEC_LENGTH (tparms);
10726 tree vec = make_tree_vec (ntparms);
10728 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10732 for (i = 0; i < ntparms; ++i)
10733 if (! TREE_VEC_ELT (vec, i))
10736 if (verify_class_unification (vec, parms, args))
10742 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10743 Pick the most specialized template, and return the corresponding
10744 instantiation, or if there is no corresponding instantiation, the
10745 template itself. If there is no most specialized template,
10746 error_mark_node is returned. If there are no templates at all,
10747 NULL_TREE is returned. */
10750 most_specialized_instantiation (tree instantiations)
10754 if (!instantiations)
10757 ++processing_template_decl;
10759 champ = instantiations;
10760 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10764 if (get_bindings (TREE_VALUE (champ),
10765 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10766 NULL_TREE, /*check_ret=*/false))
10769 if (get_bindings (TREE_VALUE (fn),
10770 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10771 NULL_TREE, /*check_ret=*/false))
10777 /* Equally specialized, move to next function. If there
10778 is no next function, nothing's most specialized. */
10779 fn = TREE_CHAIN (fn);
10785 /* Now verify that champ is better than everything earlier in the
10786 instantiation list. */
10787 for (fn = instantiations; fn != champ; fn = TREE_CHAIN (fn))
10788 if (get_bindings (TREE_VALUE (champ),
10789 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10790 NULL_TREE, /*check_ret=*/false)
10791 || !get_bindings (TREE_VALUE (fn),
10792 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10793 NULL_TREE, /*check_ret=*/false))
10799 processing_template_decl--;
10802 return error_mark_node;
10804 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10807 /* Return the most specialized of the list of templates in FNS that can
10808 produce an instantiation matching DECL, given the explicit template
10809 arguments EXPLICIT_ARGS. */
10812 most_specialized (tree fns, tree decl, tree explicit_args)
10814 tree candidates = NULL_TREE;
10817 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10819 tree candidate = TREE_VALUE (fn);
10821 args = get_bindings (candidate, decl, explicit_args, /*check_ret=*/true);
10823 candidates = tree_cons (NULL_TREE, candidate, candidates);
10826 return most_specialized_instantiation (candidates);
10829 /* If DECL is a specialization of some template, return the most
10830 general such template. Otherwise, returns NULL_TREE.
10832 For example, given:
10834 template <class T> struct S { template <class U> void f(U); };
10836 if TMPL is `template <class U> void S<int>::f(U)' this will return
10837 the full template. This function will not trace past partial
10838 specializations, however. For example, given in addition:
10840 template <class T> struct S<T*> { template <class U> void f(U); };
10842 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10843 `template <class T> template <class U> S<T*>::f(U)'. */
10846 most_general_template (tree decl)
10848 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10849 an immediate specialization. */
10850 if (TREE_CODE (decl) == FUNCTION_DECL)
10852 if (DECL_TEMPLATE_INFO (decl)) {
10853 decl = DECL_TI_TEMPLATE (decl);
10855 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10856 template friend. */
10857 if (TREE_CODE (decl) != TEMPLATE_DECL)
10863 /* Look for more and more general templates. */
10864 while (DECL_TEMPLATE_INFO (decl))
10866 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10867 (See cp-tree.h for details.) */
10868 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10871 if (CLASS_TYPE_P (TREE_TYPE (decl))
10872 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10875 /* Stop if we run into an explicitly specialized class template. */
10876 if (!DECL_NAMESPACE_SCOPE_P (decl)
10877 && DECL_CONTEXT (decl)
10878 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10881 decl = DECL_TI_TEMPLATE (decl);
10887 /* Return the most specialized of the class template specializations
10888 of TMPL which can produce an instantiation matching ARGS, or
10889 error_mark_node if the choice is ambiguous. */
10892 most_specialized_class (tree tmpl, tree args)
10894 tree list = NULL_TREE;
10899 tmpl = most_general_template (tmpl);
10900 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10903 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10906 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10907 TREE_TYPE (list) = TREE_TYPE (t);
10916 t = TREE_CHAIN (t);
10917 for (; t; t = TREE_CHAIN (t))
10919 fate = more_specialized_class (champ, t, args);
10926 t = TREE_CHAIN (t);
10928 return error_mark_node;
10934 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10936 fate = more_specialized_class (champ, t, args);
10938 return error_mark_node;
10944 /* Explicitly instantiate DECL. */
10947 do_decl_instantiation (tree decl, tree storage)
10949 tree result = NULL_TREE;
10953 /* An error occurred, for which grokdeclarator has already issued
10954 an appropriate message. */
10956 else if (! DECL_LANG_SPECIFIC (decl))
10958 error ("explicit instantiation of non-template %q#D", decl);
10961 else if (TREE_CODE (decl) == VAR_DECL)
10963 /* There is an asymmetry here in the way VAR_DECLs and
10964 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10965 the latter, the DECL we get back will be marked as a
10966 template instantiation, and the appropriate
10967 DECL_TEMPLATE_INFO will be set up. This does not happen for
10968 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10969 should handle VAR_DECLs as it currently handles
10971 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10972 if (!result || TREE_CODE (result) != VAR_DECL)
10974 error ("no matching template for %qD found", decl);
10978 else if (TREE_CODE (decl) != FUNCTION_DECL)
10980 error ("explicit instantiation of %q#D", decl);
10986 /* Check for various error cases. Note that if the explicit
10987 instantiation is valid the RESULT will currently be marked as an
10988 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10989 until we get here. */
10991 if (DECL_TEMPLATE_SPECIALIZATION (result))
10993 /* DR 259 [temp.spec].
10995 Both an explicit instantiation and a declaration of an explicit
10996 specialization shall not appear in a program unless the explicit
10997 instantiation follows a declaration of the explicit specialization.
10999 For a given set of template parameters, if an explicit
11000 instantiation of a template appears after a declaration of an
11001 explicit specialization for that template, the explicit
11002 instantiation has no effect. */
11005 else if (DECL_EXPLICIT_INSTANTIATION (result))
11009 No program shall explicitly instantiate any template more
11012 We check DECL_NOT_REALLY_EXTERN so as not to complain when
11013 the first instantiation was `extern' and the second is not,
11014 and EXTERN_P for the opposite case. */
11015 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
11016 pedwarn ("duplicate explicit instantiation of %q#D", result);
11017 /* If an "extern" explicit instantiation follows an ordinary
11018 explicit instantiation, the template is instantiated. */
11022 else if (!DECL_IMPLICIT_INSTANTIATION (result))
11024 error ("no matching template for %qD found", result);
11027 else if (!DECL_TEMPLATE_INFO (result))
11029 pedwarn ("explicit instantiation of non-template %q#D", result);
11033 if (storage == NULL_TREE)
11035 else if (storage == ridpointers[(int) RID_EXTERN])
11037 if (pedantic && !in_system_header)
11038 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
11043 error ("storage class %qD applied to template instantiation", storage);
11045 check_explicit_instantiation_namespace (result);
11046 mark_decl_instantiated (result, extern_p);
11048 instantiate_decl (result, /*defer_ok=*/1,
11049 /*expl_inst_class_mem_p=*/false);
11053 mark_class_instantiated (tree t, int extern_p)
11055 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
11056 SET_CLASSTYPE_INTERFACE_KNOWN (t);
11057 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
11058 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
11061 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
11062 rest_of_type_compilation (t, 1);
11066 /* Called from do_type_instantiation through binding_table_foreach to
11067 do recursive instantiation for the type bound in ENTRY. */
11069 bt_instantiate_type_proc (binding_entry entry, void *data)
11071 tree storage = *(tree *) data;
11073 if (IS_AGGR_TYPE (entry->type)
11074 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
11075 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
11078 /* Called from do_type_instantiation to instantiate a member
11079 (a member function or a static member variable) of an
11080 explicitly instantiated class template. */
11082 instantiate_class_member (tree decl, int extern_p)
11084 mark_decl_instantiated (decl, extern_p);
11086 instantiate_decl (decl, /*defer_ok=*/1,
11087 /*expl_inst_class_mem_p=*/true);
11090 /* Perform an explicit instantiation of template class T. STORAGE, if
11091 non-null, is the RID for extern, inline or static. COMPLAIN is
11092 nonzero if this is called from the parser, zero if called recursively,
11093 since the standard is unclear (as detailed below). */
11096 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
11101 int previous_instantiation_extern_p = 0;
11103 if (TREE_CODE (t) == TYPE_DECL)
11106 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
11108 error ("explicit instantiation of non-template type %qT", t);
11114 if (!COMPLETE_TYPE_P (t))
11116 if (complain & tf_error)
11117 error ("explicit instantiation of %q#T before definition of template",
11122 if (storage != NULL_TREE)
11124 if (pedantic && !in_system_header)
11125 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
11128 if (storage == ridpointers[(int) RID_INLINE])
11130 else if (storage == ridpointers[(int) RID_EXTERN])
11132 else if (storage == ridpointers[(int) RID_STATIC])
11136 error ("storage class %qD applied to template instantiation",
11142 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
11144 /* DR 259 [temp.spec].
11146 Both an explicit instantiation and a declaration of an explicit
11147 specialization shall not appear in a program unless the explicit
11148 instantiation follows a declaration of the explicit specialization.
11150 For a given set of template parameters, if an explicit
11151 instantiation of a template appears after a declaration of an
11152 explicit specialization for that template, the explicit
11153 instantiation has no effect. */
11156 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
11160 No program shall explicitly instantiate any template more
11163 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
11164 instantiation was `extern'. If EXTERN_P then the second is.
11165 These cases are OK. */
11166 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11168 if (!previous_instantiation_extern_p && !extern_p
11169 && (complain & tf_error))
11170 pedwarn ("duplicate explicit instantiation of %q#T", t);
11172 /* If we've already instantiated the template, just return now. */
11173 if (!CLASSTYPE_INTERFACE_ONLY (t))
11177 check_explicit_instantiation_namespace (TYPE_NAME (t));
11178 mark_class_instantiated (t, extern_p);
11186 /* In contrast to implicit instantiation, where only the
11187 declarations, and not the definitions, of members are
11188 instantiated, we have here:
11192 The explicit instantiation of a class template specialization
11193 implies the instantiation of all of its members not
11194 previously explicitly specialized in the translation unit
11195 containing the explicit instantiation.
11197 Of course, we can't instantiate member template classes, since
11198 we don't have any arguments for them. Note that the standard
11199 is unclear on whether the instantiation of the members are
11200 *explicit* instantiations or not. However, the most natural
11201 interpretation is that it should be an explicit instantiation. */
11204 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11205 if (TREE_CODE (tmp) == FUNCTION_DECL
11206 && DECL_TEMPLATE_INSTANTIATION (tmp))
11207 instantiate_class_member (tmp, extern_p);
11209 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11210 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11211 instantiate_class_member (tmp, extern_p);
11213 if (CLASSTYPE_NESTED_UTDS (t))
11214 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11215 bt_instantiate_type_proc, &storage);
11219 /* Given a function DECL, which is a specialization of TMPL, modify
11220 DECL to be a re-instantiation of TMPL with the same template
11221 arguments. TMPL should be the template into which tsubst'ing
11222 should occur for DECL, not the most general template.
11224 One reason for doing this is a scenario like this:
11227 void f(const T&, int i);
11229 void g() { f(3, 7); }
11232 void f(const T& t, const int i) { }
11234 Note that when the template is first instantiated, with
11235 instantiate_template, the resulting DECL will have no name for the
11236 first parameter, and the wrong type for the second. So, when we go
11237 to instantiate the DECL, we regenerate it. */
11240 regenerate_decl_from_template (tree decl, tree tmpl)
11242 /* The arguments used to instantiate DECL, from the most general
11247 args = DECL_TI_ARGS (decl);
11248 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11250 /* Make sure that we can see identifiers, and compute access
11252 push_access_scope (decl);
11254 if (TREE_CODE (decl) == FUNCTION_DECL)
11262 args_depth = TMPL_ARGS_DEPTH (args);
11263 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11264 if (args_depth > parms_depth)
11265 args = get_innermost_template_args (args, parms_depth);
11267 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11268 args, tf_error, NULL_TREE);
11270 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11273 /* Merge parameter declarations. */
11274 decl_parm = skip_artificial_parms_for (decl,
11275 DECL_ARGUMENTS (decl));
11277 = skip_artificial_parms_for (code_pattern,
11278 DECL_ARGUMENTS (code_pattern));
11284 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11285 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11286 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11288 parm_type = type_decays_to (parm_type);
11289 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11290 TREE_TYPE (decl_parm) = parm_type;
11291 attributes = DECL_ATTRIBUTES (pattern_parm);
11292 if (DECL_ATTRIBUTES (decl_parm) != attributes)
11294 DECL_ATTRIBUTES (decl_parm) = attributes;
11295 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
11297 decl_parm = TREE_CHAIN (decl_parm);
11298 pattern_parm = TREE_CHAIN (pattern_parm);
11301 /* Merge additional specifiers from the CODE_PATTERN. */
11302 if (DECL_DECLARED_INLINE_P (code_pattern)
11303 && !DECL_DECLARED_INLINE_P (decl))
11304 DECL_DECLARED_INLINE_P (decl) = 1;
11305 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11306 DECL_INLINE (decl) = 1;
11308 else if (TREE_CODE (decl) == VAR_DECL)
11309 DECL_INITIAL (decl) =
11310 tsubst_expr (DECL_INITIAL (code_pattern), args,
11311 tf_error, DECL_TI_TEMPLATE (decl));
11313 gcc_unreachable ();
11315 pop_access_scope (decl);
11318 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11319 substituted to get DECL. */
11322 template_for_substitution (tree decl)
11324 tree tmpl = DECL_TI_TEMPLATE (decl);
11326 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11327 for the instantiation. This is not always the most general
11328 template. Consider, for example:
11331 struct S { template <class U> void f();
11332 template <> void f<int>(); };
11334 and an instantiation of S<double>::f<int>. We want TD to be the
11335 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11336 while (/* An instantiation cannot have a definition, so we need a
11337 more general template. */
11338 DECL_TEMPLATE_INSTANTIATION (tmpl)
11339 /* We must also deal with friend templates. Given:
11341 template <class T> struct S {
11342 template <class U> friend void f() {};
11345 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11346 so far as the language is concerned, but that's still
11347 where we get the pattern for the instantiation from. On
11348 other hand, if the definition comes outside the class, say:
11350 template <class T> struct S {
11351 template <class U> friend void f();
11353 template <class U> friend void f() {}
11355 we don't need to look any further. That's what the check for
11356 DECL_INITIAL is for. */
11357 || (TREE_CODE (decl) == FUNCTION_DECL
11358 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11359 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11361 /* The present template, TD, should not be a definition. If it
11362 were a definition, we should be using it! Note that we
11363 cannot restructure the loop to just keep going until we find
11364 a template with a definition, since that might go too far if
11365 a specialization was declared, but not defined. */
11366 gcc_assert (TREE_CODE (decl) != VAR_DECL
11367 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11369 /* Fetch the more general template. */
11370 tmpl = DECL_TI_TEMPLATE (tmpl);
11376 /* Produce the definition of D, a _DECL generated from a template. If
11377 DEFER_OK is nonzero, then we don't have to actually do the
11378 instantiation now; we just have to do it sometime. Normally it is
11379 an error if this is an explicit instantiation but D is undefined.
11380 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
11381 explicitly instantiated class template. */
11384 instantiate_decl (tree d, int defer_ok,
11385 bool expl_inst_class_mem_p)
11387 tree tmpl = DECL_TI_TEMPLATE (d);
11394 bool pattern_defined;
11396 location_t saved_loc = input_location;
11399 /* This function should only be used to instantiate templates for
11400 functions and static member variables. */
11401 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11402 || TREE_CODE (d) == VAR_DECL);
11404 /* Variables are never deferred; if instantiation is required, they
11405 are instantiated right away. That allows for better code in the
11406 case that an expression refers to the value of the variable --
11407 if the variable has a constant value the referring expression can
11408 take advantage of that fact. */
11409 if (TREE_CODE (d) == VAR_DECL)
11412 /* Don't instantiate cloned functions. Instead, instantiate the
11413 functions they cloned. */
11414 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11415 d = DECL_CLONED_FUNCTION (d);
11417 if (DECL_TEMPLATE_INSTANTIATED (d))
11418 /* D has already been instantiated. It might seem reasonable to
11419 check whether or not D is an explicit instantiation, and, if so,
11420 stop here. But when an explicit instantiation is deferred
11421 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11422 is set, even though we still need to do the instantiation. */
11425 /* If we already have a specialization of this declaration, then
11426 there's no reason to instantiate it. Note that
11427 retrieve_specialization gives us both instantiations and
11428 specializations, so we must explicitly check
11429 DECL_TEMPLATE_SPECIALIZATION. */
11430 gen_tmpl = most_general_template (tmpl);
11431 gen_args = DECL_TI_ARGS (d);
11432 spec = retrieve_specialization (gen_tmpl, gen_args,
11433 /*class_specializations_p=*/false);
11434 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11437 /* This needs to happen before any tsubsting. */
11438 if (! push_tinst_level (d))
11441 timevar_push (TV_PARSE);
11443 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11444 for the instantiation. */
11445 td = template_for_substitution (d);
11446 code_pattern = DECL_TEMPLATE_RESULT (td);
11448 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11449 || DECL_TEMPLATE_SPECIALIZATION (td))
11450 /* In the case of a friend template whose definition is provided
11451 outside the class, we may have too many arguments. Drop the
11452 ones we don't need. The same is true for specializations. */
11453 args = get_innermost_template_args
11454 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11458 if (TREE_CODE (d) == FUNCTION_DECL)
11459 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11461 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11463 /* We may be in the middle of deferred access check. Disable it now. */
11464 push_deferring_access_checks (dk_no_deferred);
11466 /* Unless an explicit instantiation directive has already determined
11467 the linkage of D, remember that a definition is available for
11469 if (pattern_defined
11470 && !DECL_INTERFACE_KNOWN (d)
11471 && !DECL_NOT_REALLY_EXTERN (d))
11472 mark_definable (d);
11474 input_location = DECL_SOURCE_LOCATION (d);
11476 /* If D is a member of an explicitly instantiated class template,
11477 and no definition is available, treat it like an implicit
11479 if (!pattern_defined && expl_inst_class_mem_p
11480 && DECL_EXPLICIT_INSTANTIATION (d))
11482 DECL_NOT_REALLY_EXTERN (d) = 0;
11483 DECL_INTERFACE_KNOWN (d) = 0;
11484 SET_DECL_IMPLICIT_INSTANTIATION (d);
11489 /* Recheck the substitutions to obtain any warning messages
11490 about ignoring cv qualifiers. */
11491 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11492 tree type = TREE_TYPE (gen);
11494 /* Make sure that we can see identifiers, and compute access
11495 correctly. D is already the target FUNCTION_DECL with the
11497 push_access_scope (d);
11499 if (TREE_CODE (gen) == FUNCTION_DECL)
11501 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11502 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11503 tf_error | tf_warning, d);
11504 /* Don't simply tsubst the function type, as that will give
11505 duplicate warnings about poor parameter qualifications.
11506 The function arguments are the same as the decl_arguments
11507 without the top level cv qualifiers. */
11508 type = TREE_TYPE (type);
11510 tsubst (type, gen_args, tf_error | tf_warning, d);
11512 pop_access_scope (d);
11515 /* Check to see whether we know that this template will be
11516 instantiated in some other file, as with "extern template"
11518 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
11519 /* In general, we do not instantiate such templates... */
11521 /* ... but we instantiate inline functions so that we can inline
11523 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
11524 /* ... we instantiate static data members whose values are
11525 needed in integral constant expressions. */
11526 && ! (TREE_CODE (d) == VAR_DECL
11527 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
11529 /* Defer all other templates, unless we have been explicitly
11530 forbidden from doing so. */
11531 if (/* If there is no definition, we cannot instantiate the
11534 /* If it's OK to postpone instantiation, do so. */
11536 /* If this is a static data member that will be defined
11537 elsewhere, we don't want to instantiate the entire data
11538 member, but we do want to instantiate the initializer so that
11539 we can substitute that elsewhere. */
11540 || (external_p && TREE_CODE (d) == VAR_DECL))
11542 /* The definition of the static data member is now required so
11543 we must substitute the initializer. */
11544 if (TREE_CODE (d) == VAR_DECL
11545 && !DECL_INITIAL (d)
11546 && DECL_INITIAL (code_pattern))
11548 push_nested_class (DECL_CONTEXT (d));
11550 = tsubst_expr (DECL_INITIAL (code_pattern),
11552 tf_error | tf_warning, NULL_TREE);
11553 pop_nested_class ();
11556 /* We restore the source position here because it's used by
11557 add_pending_template. */
11558 input_location = saved_loc;
11560 if (at_eof && !pattern_defined
11561 && DECL_EXPLICIT_INSTANTIATION (d))
11564 The definition of a non-exported function template, a
11565 non-exported member function template, or a non-exported
11566 member function or static data member of a class template
11567 shall be present in every translation unit in which it is
11568 explicitly instantiated. */
11570 ("explicit instantiation of %qD but no definition available", d);
11572 /* ??? Historically, we have instantiated inline functions, even
11573 when marked as "extern template". */
11574 if (!(external_p && TREE_CODE (d) == VAR_DECL))
11575 add_pending_template (d);
11578 /* Tell the repository that D is available in this translation unit
11579 -- and see if it is supposed to be instantiated here. */
11580 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11582 /* In a PCH file, despite the fact that the repository hasn't
11583 requested instantiation in the PCH it is still possible that
11584 an instantiation will be required in a file that includes the
11587 add_pending_template (d);
11588 /* Instantiate inline functions so that the inliner can do its
11589 job, even though we'll not be emitting a copy of this
11591 if (!(TREE_CODE (d) == FUNCTION_DECL
11592 && flag_inline_trees
11593 && DECL_DECLARED_INLINE_P (d)))
11597 need_push = !cfun || !global_bindings_p ();
11599 push_to_top_level ();
11601 /* Mark D as instantiated so that recursive calls to
11602 instantiate_decl do not try to instantiate it again. */
11603 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11605 /* Regenerate the declaration in case the template has been modified
11606 by a subsequent redeclaration. */
11607 regenerate_decl_from_template (d, td);
11609 /* We already set the file and line above. Reset them now in case
11610 they changed as a result of calling regenerate_decl_from_template. */
11611 input_location = DECL_SOURCE_LOCATION (d);
11613 if (TREE_CODE (d) == VAR_DECL)
11615 /* Clear out DECL_RTL; whatever was there before may not be right
11616 since we've reset the type of the declaration. */
11617 SET_DECL_RTL (d, NULL_RTX);
11618 DECL_IN_AGGR_P (d) = 0;
11620 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11621 initializer. That function will defer actual emission until
11622 we have a chance to determine linkage. */
11623 DECL_EXTERNAL (d) = 0;
11625 /* Enter the scope of D so that access-checking works correctly. */
11626 push_nested_class (DECL_CONTEXT (d));
11627 cp_finish_decl (d, DECL_INITIAL (d), NULL_TREE, 0);
11628 pop_nested_class ();
11630 else if (TREE_CODE (d) == FUNCTION_DECL)
11632 htab_t saved_local_specializations;
11637 /* Save away the current list, in case we are instantiating one
11638 template from within the body of another. */
11639 saved_local_specializations = local_specializations;
11641 /* Set up the list of local specializations. */
11642 local_specializations = htab_create (37,
11643 hash_local_specialization,
11644 eq_local_specializations,
11647 /* Set up context. */
11648 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11650 /* Create substitution entries for the parameters. */
11651 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11652 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11653 spec_parm = DECL_ARGUMENTS (d);
11654 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11656 register_local_specialization (spec_parm, tmpl_parm);
11657 spec_parm = skip_artificial_parms_for (d, spec_parm);
11658 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11662 register_local_specialization (spec_parm, tmpl_parm);
11663 tmpl_parm = TREE_CHAIN (tmpl_parm);
11664 spec_parm = TREE_CHAIN (spec_parm);
11666 gcc_assert (!spec_parm);
11668 /* Substitute into the body of the function. */
11669 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11670 tf_error | tf_warning, tmpl);
11672 /* We don't need the local specializations any more. */
11673 htab_delete (local_specializations);
11674 local_specializations = saved_local_specializations;
11676 /* Finish the function. */
11677 d = finish_function (0);
11678 expand_or_defer_fn (d);
11681 /* We're not deferring instantiation any more. */
11682 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11685 pop_from_top_level ();
11688 input_location = saved_loc;
11689 pop_deferring_access_checks ();
11690 pop_tinst_level ();
11692 timevar_pop (TV_PARSE);
11697 /* Run through the list of templates that we wish we could
11698 instantiate, and instantiate any we can. RETRIES is the
11699 number of times we retry pending template instantiation. */
11702 instantiate_pending_templates (int retries)
11705 tree last = NULL_TREE;
11707 location_t saved_loc = input_location;
11708 int saved_in_system_header = in_system_header;
11710 /* Instantiating templates may trigger vtable generation. This in turn
11711 may require further template instantiations. We place a limit here
11712 to avoid infinite loop. */
11713 if (pending_templates && retries >= max_tinst_depth)
11715 error ("template instantiation depth exceeds maximum of %d"
11716 " instantiating %q+D, possibly from virtual table generation"
11717 " (use -ftemplate-depth-NN to increase the maximum)",
11718 max_tinst_depth, TREE_VALUE (pending_templates));
11726 t = &pending_templates;
11729 tree instantiation = TREE_VALUE (*t);
11731 reopen_tinst_level (TREE_PURPOSE (*t));
11733 if (TYPE_P (instantiation))
11737 if (!COMPLETE_TYPE_P (instantiation))
11739 instantiate_class_template (instantiation);
11740 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11741 for (fn = TYPE_METHODS (instantiation);
11743 fn = TREE_CHAIN (fn))
11744 if (! DECL_ARTIFICIAL (fn))
11745 instantiate_decl (fn,
11747 /*expl_inst_class_mem_p=*/false);
11748 if (COMPLETE_TYPE_P (instantiation))
11752 if (COMPLETE_TYPE_P (instantiation))
11753 /* If INSTANTIATION has been instantiated, then we don't
11754 need to consider it again in the future. */
11755 *t = TREE_CHAIN (*t);
11759 t = &TREE_CHAIN (*t);
11764 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11765 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11768 = instantiate_decl (instantiation,
11770 /*expl_inst_class_mem_p=*/false);
11771 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11775 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11776 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11777 /* If INSTANTIATION has been instantiated, then we don't
11778 need to consider it again in the future. */
11779 *t = TREE_CHAIN (*t);
11783 t = &TREE_CHAIN (*t);
11787 current_tinst_level = NULL_TREE;
11789 last_pending_template = last;
11791 while (reconsider);
11793 input_location = saved_loc;
11794 in_system_header = saved_in_system_header;
11797 /* Substitute ARGVEC into T, which is a list of initializers for
11798 either base class or a non-static data member. The TREE_PURPOSEs
11799 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11800 instantiate_decl. */
11803 tsubst_initializer_list (tree t, tree argvec)
11805 tree inits = NULL_TREE;
11807 for (; t; t = TREE_CHAIN (t))
11812 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11814 decl = expand_member_init (decl);
11815 if (decl && !DECL_P (decl))
11816 in_base_initializer = 1;
11818 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11820 in_base_initializer = 0;
11824 init = build_tree_list (decl, init);
11825 TREE_CHAIN (init) = inits;
11832 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11835 set_current_access_from_decl (tree decl)
11837 if (TREE_PRIVATE (decl))
11838 current_access_specifier = access_private_node;
11839 else if (TREE_PROTECTED (decl))
11840 current_access_specifier = access_protected_node;
11842 current_access_specifier = access_public_node;
11845 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11846 is the instantiation (which should have been created with
11847 start_enum) and ARGS are the template arguments to use. */
11850 tsubst_enum (tree tag, tree newtag, tree args)
11854 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11859 decl = TREE_VALUE (e);
11860 /* Note that in a template enum, the TREE_VALUE is the
11861 CONST_DECL, not the corresponding INTEGER_CST. */
11862 value = tsubst_expr (DECL_INITIAL (decl),
11863 args, tf_error | tf_warning,
11866 /* Give this enumeration constant the correct access. */
11867 set_current_access_from_decl (decl);
11869 /* Actually build the enumerator itself. */
11870 build_enumerator (DECL_NAME (decl), value, newtag);
11873 finish_enum (newtag);
11874 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11875 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11878 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11879 its type -- but without substituting the innermost set of template
11880 arguments. So, innermost set of template parameters will appear in
11884 get_mostly_instantiated_function_type (tree decl)
11892 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11893 targs = DECL_TI_ARGS (decl);
11894 tparms = DECL_TEMPLATE_PARMS (tmpl);
11895 parm_depth = TMPL_PARMS_DEPTH (tparms);
11897 /* There should be as many levels of arguments as there are levels
11899 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11901 fn_type = TREE_TYPE (tmpl);
11903 if (parm_depth == 1)
11904 /* No substitution is necessary. */
11908 int i, save_access_control;
11911 /* Replace the innermost level of the TARGS with NULL_TREEs to
11912 let tsubst know not to substitute for those parameters. */
11913 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11914 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11915 SET_TMPL_ARGS_LEVEL (partial_args, i,
11916 TMPL_ARGS_LEVEL (targs, i));
11917 SET_TMPL_ARGS_LEVEL (partial_args,
11918 TMPL_ARGS_DEPTH (targs),
11919 make_tree_vec (DECL_NTPARMS (tmpl)));
11921 /* Disable access control as this function is used only during
11923 save_access_control = flag_access_control;
11924 flag_access_control = 0;
11926 ++processing_template_decl;
11927 /* Now, do the (partial) substitution to figure out the
11928 appropriate function type. */
11929 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11930 --processing_template_decl;
11932 /* Substitute into the template parameters to obtain the real
11933 innermost set of parameters. This step is important if the
11934 innermost set of template parameters contains value
11935 parameters whose types depend on outer template parameters. */
11936 TREE_VEC_LENGTH (partial_args)--;
11937 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11939 flag_access_control = save_access_control;
11945 /* Return truthvalue if we're processing a template different from
11946 the last one involved in diagnostics. */
11948 problematic_instantiation_changed (void)
11950 return last_template_error_tick != tinst_level_tick;
11953 /* Remember current template involved in diagnostics. */
11955 record_last_problematic_instantiation (void)
11957 last_template_error_tick = tinst_level_tick;
11961 current_instantiation (void)
11963 return current_tinst_level;
11966 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11967 type. Return zero for ok, nonzero for disallowed. Issue error and
11968 warning messages under control of COMPLAIN. */
11971 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11973 if (INTEGRAL_TYPE_P (type))
11975 else if (POINTER_TYPE_P (type))
11977 else if (TYPE_PTR_TO_MEMBER_P (type))
11979 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11981 else if (TREE_CODE (type) == TYPENAME_TYPE)
11984 if (complain & tf_error)
11985 error ("%q#T is not a valid type for a template constant parameter", type);
11989 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11990 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11993 dependent_type_p_r (tree type)
11999 A type is dependent if it is:
12001 -- a template parameter. Template template parameters are types
12002 for us (since TYPE_P holds true for them) so we handle
12004 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
12005 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
12007 /* -- a qualified-id with a nested-name-specifier which contains a
12008 class-name that names a dependent type or whose unqualified-id
12009 names a dependent type. */
12010 if (TREE_CODE (type) == TYPENAME_TYPE)
12012 /* -- a cv-qualified type where the cv-unqualified type is
12014 type = TYPE_MAIN_VARIANT (type);
12015 /* -- a compound type constructed from any dependent type. */
12016 if (TYPE_PTR_TO_MEMBER_P (type))
12017 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
12018 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
12020 else if (TREE_CODE (type) == POINTER_TYPE
12021 || TREE_CODE (type) == REFERENCE_TYPE)
12022 return dependent_type_p (TREE_TYPE (type));
12023 else if (TREE_CODE (type) == FUNCTION_TYPE
12024 || TREE_CODE (type) == METHOD_TYPE)
12028 if (dependent_type_p (TREE_TYPE (type)))
12030 for (arg_type = TYPE_ARG_TYPES (type);
12032 arg_type = TREE_CHAIN (arg_type))
12033 if (dependent_type_p (TREE_VALUE (arg_type)))
12037 /* -- an array type constructed from any dependent type or whose
12038 size is specified by a constant expression that is
12039 value-dependent. */
12040 if (TREE_CODE (type) == ARRAY_TYPE)
12042 if (TYPE_DOMAIN (type)
12043 && ((value_dependent_expression_p
12044 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
12045 || (type_dependent_expression_p
12046 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
12048 return dependent_type_p (TREE_TYPE (type));
12051 /* -- a template-id in which either the template name is a template
12053 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
12055 /* ... or any of the template arguments is a dependent type or
12056 an expression that is type-dependent or value-dependent. */
12057 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
12058 && (any_dependent_template_arguments_p
12059 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
12062 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
12063 expression is not type-dependent, then it should already been
12065 if (TREE_CODE (type) == TYPEOF_TYPE)
12068 /* The standard does not specifically mention types that are local
12069 to template functions or local classes, but they should be
12070 considered dependent too. For example:
12072 template <int I> void f() {
12077 The size of `E' cannot be known until the value of `I' has been
12078 determined. Therefore, `E' must be considered dependent. */
12079 scope = TYPE_CONTEXT (type);
12080 if (scope && TYPE_P (scope))
12081 return dependent_type_p (scope);
12082 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
12083 return type_dependent_expression_p (scope);
12085 /* Other types are non-dependent. */
12089 /* Returns TRUE if TYPE is dependent, in the sense of
12090 [temp.dep.type]. */
12093 dependent_type_p (tree type)
12095 /* If there are no template parameters in scope, then there can't be
12096 any dependent types. */
12097 if (!processing_template_decl)
12100 /* If the type is NULL, we have not computed a type for the entity
12101 in question; in that case, the type is dependent. */
12105 /* Erroneous types can be considered non-dependent. */
12106 if (type == error_mark_node)
12109 /* If we have not already computed the appropriate value for TYPE,
12111 if (!TYPE_DEPENDENT_P_VALID (type))
12113 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
12114 TYPE_DEPENDENT_P_VALID (type) = 1;
12117 return TYPE_DEPENDENT_P (type);
12120 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
12123 dependent_scope_ref_p (tree expression, bool criterion (tree))
12128 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
12130 if (!TYPE_P (TREE_OPERAND (expression, 0)))
12133 scope = TREE_OPERAND (expression, 0);
12134 name = TREE_OPERAND (expression, 1);
12138 An id-expression is type-dependent if it contains a
12139 nested-name-specifier that contains a class-name that names a
12141 /* The suggested resolution to Core Issue 2 implies that if the
12142 qualifying type is the current class, then we must peek
12145 && currently_open_class (scope)
12146 && !criterion (name))
12148 if (dependent_type_p (scope))
12154 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
12155 [temp.dep.constexpr] */
12158 value_dependent_expression_p (tree expression)
12160 if (!processing_template_decl)
12163 /* A name declared with a dependent type. */
12164 if (DECL_P (expression) && type_dependent_expression_p (expression))
12167 switch (TREE_CODE (expression))
12169 case IDENTIFIER_NODE:
12170 /* A name that has not been looked up -- must be dependent. */
12173 case TEMPLATE_PARM_INDEX:
12174 /* A non-type template parm. */
12178 /* A non-type template parm. */
12179 if (DECL_TEMPLATE_PARM_P (expression))
12184 /* A constant with integral or enumeration type and is initialized
12185 with an expression that is value-dependent. */
12186 if (DECL_INITIAL (expression)
12187 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
12188 && value_dependent_expression_p (DECL_INITIAL (expression)))
12192 case DYNAMIC_CAST_EXPR:
12193 case STATIC_CAST_EXPR:
12194 case CONST_CAST_EXPR:
12195 case REINTERPRET_CAST_EXPR:
12197 /* These expressions are value-dependent if the type to which
12198 the cast occurs is dependent or the expression being casted
12199 is value-dependent. */
12201 tree type = TREE_TYPE (expression);
12203 if (dependent_type_p (type))
12206 /* A functional cast has a list of operands. */
12207 expression = TREE_OPERAND (expression, 0);
12210 /* If there are no operands, it must be an expression such
12211 as "int()". This should not happen for aggregate types
12212 because it would form non-constant expressions. */
12213 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12218 if (TREE_CODE (expression) == TREE_LIST)
12220 for (; expression; expression = TREE_CHAIN (expression))
12221 if (value_dependent_expression_p (TREE_VALUE (expression)))
12226 return value_dependent_expression_p (expression);
12231 /* A `sizeof' expression is value-dependent if the operand is
12233 expression = TREE_OPERAND (expression, 0);
12234 if (TYPE_P (expression))
12235 return dependent_type_p (expression);
12236 return type_dependent_expression_p (expression);
12239 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12241 case COMPONENT_REF:
12242 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12243 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12246 /* A CALL_EXPR is value-dependent if any argument is
12247 value-dependent. Why do we have to handle CALL_EXPRs in this
12248 function at all? First, some function calls, those for which
12249 value_dependent_expression_p is true, man appear in constant
12250 expressions. Second, there appear to be bugs which result in
12251 other CALL_EXPRs reaching this point. */
12253 tree function = TREE_OPERAND (expression, 0);
12254 tree args = TREE_OPERAND (expression, 1);
12256 if (value_dependent_expression_p (function))
12262 if (TREE_CODE (args) == TREE_LIST)
12264 for (; args; args = TREE_CHAIN (args))
12265 if (value_dependent_expression_p (TREE_VALUE (args)))
12270 return value_dependent_expression_p (args);
12274 /* A constant expression is value-dependent if any subexpression is
12275 value-dependent. */
12276 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12278 case tcc_reference:
12280 return (value_dependent_expression_p
12281 (TREE_OPERAND (expression, 0)));
12283 case tcc_comparison:
12285 return ((value_dependent_expression_p
12286 (TREE_OPERAND (expression, 0)))
12287 || (value_dependent_expression_p
12288 (TREE_OPERAND (expression, 1))));
12290 case tcc_expression:
12293 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12294 /* In some cases, some of the operands may be missing.
12295 (For example, in the case of PREDECREMENT_EXPR, the
12296 amount to increment by may be missing.) That doesn't
12297 make the expression dependent. */
12298 if (TREE_OPERAND (expression, i)
12299 && (value_dependent_expression_p
12300 (TREE_OPERAND (expression, i))))
12310 /* The expression is not value-dependent. */
12314 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12315 [temp.dep.expr]. */
12318 type_dependent_expression_p (tree expression)
12320 if (!processing_template_decl)
12323 if (expression == error_mark_node)
12326 /* An unresolved name is always dependent. */
12327 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12330 /* Some expression forms are never type-dependent. */
12331 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12332 || TREE_CODE (expression) == SIZEOF_EXPR
12333 || TREE_CODE (expression) == ALIGNOF_EXPR
12334 || TREE_CODE (expression) == TYPEID_EXPR
12335 || TREE_CODE (expression) == DELETE_EXPR
12336 || TREE_CODE (expression) == VEC_DELETE_EXPR
12337 || TREE_CODE (expression) == THROW_EXPR)
12340 /* The types of these expressions depends only on the type to which
12341 the cast occurs. */
12342 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12343 || TREE_CODE (expression) == STATIC_CAST_EXPR
12344 || TREE_CODE (expression) == CONST_CAST_EXPR
12345 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12346 || TREE_CODE (expression) == CAST_EXPR)
12347 return dependent_type_p (TREE_TYPE (expression));
12349 /* The types of these expressions depends only on the type created
12350 by the expression. */
12351 if (TREE_CODE (expression) == NEW_EXPR
12352 || TREE_CODE (expression) == VEC_NEW_EXPR)
12354 /* For NEW_EXPR tree nodes created inside a template, either
12355 the object type itself or a TREE_LIST may appear as the
12357 tree type = TREE_OPERAND (expression, 1);
12358 if (TREE_CODE (type) == TREE_LIST)
12359 /* This is an array type. We need to check array dimensions
12361 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12362 || value_dependent_expression_p
12363 (TREE_OPERAND (TREE_VALUE (type), 1));
12365 return dependent_type_p (type);
12368 if (TREE_CODE (expression) == SCOPE_REF
12369 && dependent_scope_ref_p (expression,
12370 type_dependent_expression_p))
12373 if (TREE_CODE (expression) == FUNCTION_DECL
12374 && DECL_LANG_SPECIFIC (expression)
12375 && DECL_TEMPLATE_INFO (expression)
12376 && (any_dependent_template_arguments_p
12377 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12380 if (TREE_CODE (expression) == TEMPLATE_DECL
12381 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12384 if (TREE_TYPE (expression) == unknown_type_node)
12386 if (TREE_CODE (expression) == ADDR_EXPR)
12387 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12388 if (TREE_CODE (expression) == COMPONENT_REF
12389 || TREE_CODE (expression) == OFFSET_REF)
12391 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12393 expression = TREE_OPERAND (expression, 1);
12394 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12397 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12398 if (TREE_CODE (expression) == SCOPE_REF)
12401 if (TREE_CODE (expression) == BASELINK)
12402 expression = BASELINK_FUNCTIONS (expression);
12404 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12406 if (any_dependent_template_arguments_p
12407 (TREE_OPERAND (expression, 1)))
12409 expression = TREE_OPERAND (expression, 0);
12411 gcc_assert (TREE_CODE (expression) == OVERLOAD
12412 || TREE_CODE (expression) == FUNCTION_DECL);
12416 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12418 expression = OVL_NEXT (expression);
12423 return (dependent_type_p (TREE_TYPE (expression)));
12426 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12427 contains a type-dependent expression. */
12430 any_type_dependent_arguments_p (tree args)
12434 tree arg = TREE_VALUE (args);
12436 if (type_dependent_expression_p (arg))
12438 args = TREE_CHAIN (args);
12443 /* Returns TRUE if the ARG (a template argument) is dependent. */
12446 dependent_template_arg_p (tree arg)
12448 if (!processing_template_decl)
12451 if (TREE_CODE (arg) == TEMPLATE_DECL
12452 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12453 return dependent_template_p (arg);
12454 else if (TYPE_P (arg))
12455 return dependent_type_p (arg);
12457 return (type_dependent_expression_p (arg)
12458 || value_dependent_expression_p (arg));
12461 /* Returns true if ARGS (a collection of template arguments) contains
12462 any dependent arguments. */
12465 any_dependent_template_arguments_p (tree args)
12473 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12475 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12476 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12477 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12484 /* Returns TRUE if the template TMPL is dependent. */
12487 dependent_template_p (tree tmpl)
12489 if (TREE_CODE (tmpl) == OVERLOAD)
12493 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12495 tmpl = OVL_CHAIN (tmpl);
12500 /* Template template parameters are dependent. */
12501 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12502 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12504 /* So are names that have not been looked up. */
12505 if (TREE_CODE (tmpl) == SCOPE_REF
12506 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12508 /* So are member templates of dependent classes. */
12509 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12510 return dependent_type_p (DECL_CONTEXT (tmpl));
12514 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12517 dependent_template_id_p (tree tmpl, tree args)
12519 return (dependent_template_p (tmpl)
12520 || any_dependent_template_arguments_p (args));
12523 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12524 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12525 can be found. Note that this function peers inside uninstantiated
12526 templates and therefore should be used only in extremely limited
12527 situations. ONLY_CURRENT_P restricts this peering to the currently
12528 open classes hierarchy (which is required when comparing types). */
12531 resolve_typename_type (tree type, bool only_current_p)
12539 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12541 scope = TYPE_CONTEXT (type);
12542 name = TYPE_IDENTIFIER (type);
12544 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12545 it first before we can figure out what NAME refers to. */
12546 if (TREE_CODE (scope) == TYPENAME_TYPE)
12547 scope = resolve_typename_type (scope, only_current_p);
12548 /* If we don't know what SCOPE refers to, then we cannot resolve the
12550 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12551 return error_mark_node;
12552 /* If the SCOPE is a template type parameter, we have no way of
12553 resolving the name. */
12554 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12556 /* If the SCOPE is not the current instantiation, there's no reason
12557 to look inside it. */
12558 if (only_current_p && !currently_open_class (scope))
12559 return error_mark_node;
12560 /* If SCOPE is a partial instantiation, it will not have a valid
12561 TYPE_FIELDS list, so use the original template. */
12562 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12563 /* Enter the SCOPE so that name lookup will be resolved as if we
12564 were in the class definition. In particular, SCOPE will no
12565 longer be considered a dependent type. */
12566 pushed_scope = push_scope (scope);
12567 /* Look up the declaration. */
12568 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12569 /* Obtain the set of qualifiers applied to the TYPE. */
12570 quals = cp_type_quals (type);
12571 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12572 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12574 type = error_mark_node;
12575 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12576 && TREE_CODE (decl) == TYPE_DECL)
12577 type = TREE_TYPE (decl);
12578 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12579 && DECL_CLASS_TEMPLATE_P (decl))
12583 /* Obtain the template and the arguments. */
12584 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12585 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12586 /* Instantiate the template. */
12587 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12588 /*entering_scope=*/0, tf_error | tf_user);
12591 type = error_mark_node;
12592 /* Qualify the resulting type. */
12593 if (type != error_mark_node && quals)
12594 type = cp_build_qualified_type (type, quals);
12595 /* Leave the SCOPE. */
12597 pop_scope (pushed_scope);
12602 /* EXPR is an expression which is not type-dependent. Return a proxy
12603 for EXPR that can be used to compute the types of larger
12604 expressions containing EXPR. */
12607 build_non_dependent_expr (tree expr)
12611 /* Preserve null pointer constants so that the type of things like
12612 "p == 0" where "p" is a pointer can be determined. */
12613 if (null_ptr_cst_p (expr))
12615 /* Preserve OVERLOADs; the functions must be available to resolve
12617 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12618 TREE_OPERAND (expr, 0) : expr);
12619 if (is_overloaded_fn (inner_expr)
12620 || TREE_CODE (inner_expr) == OFFSET_REF)
12622 /* There is no need to return a proxy for a variable. */
12623 if (TREE_CODE (expr) == VAR_DECL)
12625 /* Preserve string constants; conversions from string constants to
12626 "char *" are allowed, even though normally a "const char *"
12627 cannot be used to initialize a "char *". */
12628 if (TREE_CODE (expr) == STRING_CST)
12630 /* Preserve arithmetic constants, as an optimization -- there is no
12631 reason to create a new node. */
12632 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12634 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12635 There is at least one place where we want to know that a
12636 particular expression is a throw-expression: when checking a ?:
12637 expression, there are special rules if the second or third
12638 argument is a throw-expression. */
12639 if (TREE_CODE (expr) == THROW_EXPR)
12642 if (TREE_CODE (expr) == COND_EXPR)
12643 return build3 (COND_EXPR,
12645 TREE_OPERAND (expr, 0),
12646 (TREE_OPERAND (expr, 1)
12647 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12648 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12649 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12650 if (TREE_CODE (expr) == COMPOUND_EXPR
12651 && !COMPOUND_EXPR_OVERLOADED (expr))
12652 return build2 (COMPOUND_EXPR,
12654 TREE_OPERAND (expr, 0),
12655 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12657 /* Otherwise, build a NON_DEPENDENT_EXPR.
12659 REFERENCE_TYPEs are not stripped for expressions in templates
12660 because doing so would play havoc with mangling. Consider, for
12663 template <typename T> void f<T& g>() { g(); }
12665 In the body of "f", the expression for "g" will have
12666 REFERENCE_TYPE, even though the standard says that it should
12667 not. The reason is that we must preserve the syntactic form of
12668 the expression so that mangling (say) "f<g>" inside the body of
12669 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12671 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12674 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12675 Return a new TREE_LIST with the various arguments replaced with
12676 equivalent non-dependent expressions. */
12679 build_non_dependent_args (tree args)
12684 new_args = NULL_TREE;
12685 for (a = args; a; a = TREE_CHAIN (a))
12686 new_args = tree_cons (NULL_TREE,
12687 build_non_dependent_expr (TREE_VALUE (a)),
12689 return nreverse (new_args);
12692 #include "gt-cp-pt.h"