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 /* The TYPE is being declared. If it is a template type, that means it
676 is a partial specialization. Do appropriate error-checking. */
679 maybe_process_partial_specialization (tree type)
681 /* TYPE maybe an ERROR_MARK_NODE. */
682 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
684 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
686 /* This is for ordinary explicit specialization and partial
687 specialization of a template class such as:
689 template <> class C<int>;
693 template <class T> class C<T*>;
695 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
697 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
698 && !COMPLETE_TYPE_P (type))
700 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
701 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
702 if (processing_template_decl)
703 push_template_decl (TYPE_MAIN_DECL (type));
705 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
706 error ("specialization of %qT after instantiation", type);
708 else if (CLASS_TYPE_P (type)
709 && !CLASSTYPE_USE_TEMPLATE (type)
710 && CLASSTYPE_TEMPLATE_INFO (type)
711 && context && CLASS_TYPE_P (context)
712 && CLASSTYPE_TEMPLATE_INFO (context))
714 /* This is for an explicit specialization of member class
715 template according to [temp.expl.spec/18]:
717 template <> template <class U> class C<int>::D;
719 The context `C<int>' must be an implicit instantiation.
720 Otherwise this is just a member class template declared
723 template <> class C<int> { template <class U> class D; };
724 template <> template <class U> class C<int>::D;
726 In the first case, `C<int>::D' is a specialization of `C<T>::D'
727 while in the second case, `C<int>::D' is a primary template
728 and `C<T>::D' may not exist. */
730 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
731 && !COMPLETE_TYPE_P (type))
735 if (current_namespace
736 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
738 pedwarn ("specializing %q#T in different namespace", type);
739 pedwarn (" from definition of %q+#D",
740 CLASSTYPE_TI_TEMPLATE (type));
743 /* Check for invalid specialization after instantiation:
745 template <> template <> class C<int>::D<int>;
746 template <> template <class U> class C<int>::D; */
748 for (t = DECL_TEMPLATE_INSTANTIATIONS
749 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
750 t; t = TREE_CHAIN (t))
751 if (TREE_VALUE (t) != type
752 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
753 error ("specialization %qT after instantiation %qT",
754 type, TREE_VALUE (t));
756 /* Mark TYPE as a specialization. And as a result, we only
757 have one level of template argument for the innermost
759 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
760 CLASSTYPE_TI_ARGS (type)
761 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
764 else if (processing_specialization)
765 error ("explicit specialization of non-template %qT", type);
768 /* Returns nonzero if we can optimize the retrieval of specializations
769 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
770 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
773 optimize_specialization_lookup_p (tree tmpl)
775 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
776 && DECL_CLASS_SCOPE_P (tmpl)
777 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
779 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
780 /* The optimized lookup depends on the fact that the
781 template arguments for the member function template apply
782 purely to the containing class, which is not true if the
783 containing class is an explicit or partial
785 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
786 && !DECL_MEMBER_TEMPLATE_P (tmpl)
787 && !DECL_CONV_FN_P (tmpl)
788 /* It is possible to have a template that is not a member
789 template and is not a member of a template class:
791 template <typename T>
792 struct S { friend A::f(); };
794 Here, the friend function is a template, but the context does
795 not have template information. The optimized lookup relies
796 on having ARGS be the template arguments for both the class
797 and the function template. */
798 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
801 /* Retrieve the specialization (in the sense of [temp.spec] - a
802 specialization is either an instantiation or an explicit
803 specialization) of TMPL for the given template ARGS. If there is
804 no such specialization, return NULL_TREE. The ARGS are a vector of
805 arguments, or a vector of vectors of arguments, in the case of
806 templates with more than one level of parameters.
808 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
809 then we search for a partial specialization matching ARGS. This
810 parameter is ignored if TMPL is not a class template. */
813 retrieve_specialization (tree tmpl, tree args,
814 bool class_specializations_p)
816 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
818 /* There should be as many levels of arguments as there are
819 levels of parameters. */
820 gcc_assert (TMPL_ARGS_DEPTH (args)
821 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
823 if (optimize_specialization_lookup_p (tmpl))
826 tree class_specialization;
827 VEC(tree,gc) *methods;
831 /* The template arguments actually apply to the containing
832 class. Find the class specialization with those
834 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
836 = retrieve_specialization (class_template, args,
837 /*class_specializations_p=*/false);
838 if (!class_specialization)
840 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
841 for the specialization. */
842 idx = class_method_index_for_fn (class_specialization, tmpl);
845 /* Iterate through the methods with the indicated name, looking
846 for the one that has an instance of TMPL. */
847 methods = CLASSTYPE_METHOD_VEC (class_specialization);
848 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
850 tree fn = OVL_CURRENT (fns);
851 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
861 /* Class templates store their instantiations on the
862 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
863 DECL_TEMPLATE_SPECIALIZATIONS list. */
864 if (!class_specializations_p
865 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
866 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
868 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
870 /* Iterate through the list until we find a matching template. */
871 while (*sp != NULL_TREE)
875 if (comp_template_args (TREE_PURPOSE (spec), args))
877 /* Use the move-to-front heuristic to speed up future
881 *sp = TREE_CHAIN (*sp);
882 TREE_CHAIN (spec) = *head;
885 return TREE_VALUE (spec);
887 sp = &TREE_CHAIN (spec);
894 /* Like retrieve_specialization, but for local declarations. */
897 retrieve_local_specialization (tree tmpl)
899 tree spec = htab_find_with_hash (local_specializations, tmpl,
900 htab_hash_pointer (tmpl));
901 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
904 /* Returns nonzero iff DECL is a specialization of TMPL. */
907 is_specialization_of (tree decl, tree tmpl)
911 if (TREE_CODE (decl) == FUNCTION_DECL)
915 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
921 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
923 for (t = TREE_TYPE (decl);
925 t = CLASSTYPE_USE_TEMPLATE (t)
926 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
927 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
934 /* Returns nonzero iff DECL is a specialization of friend declaration
935 FRIEND according to [temp.friend]. */
938 is_specialization_of_friend (tree decl, tree friend)
940 bool need_template = true;
943 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
944 || TREE_CODE (decl) == TYPE_DECL);
946 /* For [temp.friend/6] when FRIEND is an ordinary member function
947 of a template class, we want to check if DECL is a specialization
949 if (TREE_CODE (friend) == FUNCTION_DECL
950 && DECL_TEMPLATE_INFO (friend)
951 && !DECL_USE_TEMPLATE (friend))
953 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
954 friend = DECL_TI_TEMPLATE (friend);
955 need_template = false;
957 else if (TREE_CODE (friend) == TEMPLATE_DECL
958 && !PRIMARY_TEMPLATE_P (friend))
959 need_template = false;
961 /* There is nothing to do if this is not a template friend. */
962 if (TREE_CODE (friend) != TEMPLATE_DECL)
965 if (is_specialization_of (decl, friend))
969 A member of a class template may be declared to be a friend of a
970 non-template class. In this case, the corresponding member of
971 every specialization of the class template is a friend of the
972 class granting friendship.
974 For example, given a template friend declaration
976 template <class T> friend void A<T>::f();
978 the member function below is considered a friend
980 template <> struct A<int> {
984 For this type of template friend, TEMPLATE_DEPTH below will be
985 nonzero. To determine if DECL is a friend of FRIEND, we first
986 check if the enclosing class is a specialization of another. */
988 template_depth = template_class_depth (DECL_CONTEXT (friend));
990 && DECL_CLASS_SCOPE_P (decl)
991 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
992 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
994 /* Next, we check the members themselves. In order to handle
995 a few tricky cases, such as when FRIEND's are
997 template <class T> friend void A<T>::g(T t);
998 template <class T> template <T t> friend void A<T>::h();
1002 void A<int>::g(int);
1003 template <int> void A<int>::h();
1005 we need to figure out ARGS, the template arguments from
1006 the context of DECL. This is required for template substitution
1007 of `T' in the function parameter of `g' and template parameter
1008 of `h' in the above examples. Here ARGS corresponds to `int'. */
1010 tree context = DECL_CONTEXT (decl);
1011 tree args = NULL_TREE;
1012 int current_depth = 0;
1014 while (current_depth < template_depth)
1016 if (CLASSTYPE_TEMPLATE_INFO (context))
1018 if (current_depth == 0)
1019 args = TYPE_TI_ARGS (context);
1021 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1024 context = TYPE_CONTEXT (context);
1027 if (TREE_CODE (decl) == FUNCTION_DECL)
1032 tree friend_args_type;
1033 tree decl_args_type;
1035 /* Make sure that both DECL and FRIEND are templates or
1037 is_template = DECL_TEMPLATE_INFO (decl)
1038 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1039 if (need_template ^ is_template)
1041 else if (is_template)
1043 /* If both are templates, check template parameter list. */
1045 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1047 if (!comp_template_parms
1048 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1052 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1055 decl_type = TREE_TYPE (decl);
1057 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1058 tf_none, NULL_TREE);
1059 if (friend_type == error_mark_node)
1062 /* Check if return types match. */
1063 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1066 /* Check if function parameter types match, ignoring the
1067 `this' parameter. */
1068 friend_args_type = TYPE_ARG_TYPES (friend_type);
1069 decl_args_type = TYPE_ARG_TYPES (decl_type);
1070 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1071 friend_args_type = TREE_CHAIN (friend_args_type);
1072 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1073 decl_args_type = TREE_CHAIN (decl_args_type);
1075 return compparms (decl_args_type, friend_args_type);
1079 /* DECL is a TYPE_DECL */
1081 tree decl_type = TREE_TYPE (decl);
1083 /* Make sure that both DECL and FRIEND are templates or
1086 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1087 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1089 if (need_template ^ is_template)
1091 else if (is_template)
1094 /* If both are templates, check the name of the two
1095 TEMPLATE_DECL's first because is_friend didn't. */
1096 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1097 != DECL_NAME (friend))
1100 /* Now check template parameter list. */
1102 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1104 return comp_template_parms
1105 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1109 return (DECL_NAME (decl)
1110 == DECL_NAME (friend));
1116 /* Register the specialization SPEC as a specialization of TMPL with
1117 the indicated ARGS. Returns SPEC, or an equivalent prior
1118 declaration, if available. */
1121 register_specialization (tree spec, tree tmpl, tree args)
1125 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1127 if (TREE_CODE (spec) == FUNCTION_DECL
1128 && uses_template_parms (DECL_TI_ARGS (spec)))
1129 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1130 register it; we want the corresponding TEMPLATE_DECL instead.
1131 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1132 the more obvious `uses_template_parms (spec)' to avoid problems
1133 with default function arguments. In particular, given
1134 something like this:
1136 template <class T> void f(T t1, T t = T())
1138 the default argument expression is not substituted for in an
1139 instantiation unless and until it is actually needed. */
1142 fn = retrieve_specialization (tmpl, args,
1143 /*class_specializations_p=*/false);
1144 /* We can sometimes try to re-register a specialization that we've
1145 already got. In particular, regenerate_decl_from_template calls
1146 duplicate_decls which will update the specialization list. But,
1147 we'll still get called again here anyhow. It's more convenient
1148 to simply allow this than to try to prevent it. */
1151 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1153 if (DECL_TEMPLATE_INSTANTIATION (fn))
1156 || DECL_EXPLICIT_INSTANTIATION (fn))
1158 error ("specialization of %qD after instantiation",
1164 /* This situation should occur only if the first
1165 specialization is an implicit instantiation, the
1166 second is an explicit specialization, and the
1167 implicit instantiation has not yet been used. That
1168 situation can occur if we have implicitly
1169 instantiated a member function and then specialized
1172 We can also wind up here if a friend declaration that
1173 looked like an instantiation turns out to be a
1176 template <class T> void foo(T);
1177 class S { friend void foo<>(int) };
1178 template <> void foo(int);
1180 We transform the existing DECL in place so that any
1181 pointers to it become pointers to the updated
1184 If there was a definition for the template, but not
1185 for the specialization, we want this to look as if
1186 there were no definition, and vice versa. */
1187 DECL_INITIAL (fn) = NULL_TREE;
1188 duplicate_decls (spec, fn);
1193 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1195 if (!duplicate_decls (spec, fn) && DECL_INITIAL (spec))
1196 /* Dup decl failed, but this is a new definition. Set the
1197 line number so any errors match this new
1199 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1205 /* A specialization must be declared in the same namespace as the
1206 template it is specializing. */
1207 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1208 && !check_specialization_namespace (tmpl))
1209 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1211 if (!optimize_specialization_lookup_p (tmpl))
1212 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1213 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1218 /* Unregister the specialization SPEC as a specialization of TMPL.
1219 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1220 if the SPEC was listed as a specialization of TMPL. */
1223 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1227 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1229 s = &TREE_CHAIN (*s))
1230 if (TREE_VALUE (*s) == spec)
1233 *s = TREE_CHAIN (*s);
1235 TREE_VALUE (*s) = new_spec;
1242 /* Compare an entry in the local specializations hash table P1 (which
1243 is really a pointer to a TREE_LIST) with P2 (which is really a
1247 eq_local_specializations (const void *p1, const void *p2)
1249 return TREE_VALUE ((tree) p1) == (tree) p2;
1252 /* Hash P1, an entry in the local specializations table. */
1255 hash_local_specialization (const void* p1)
1257 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1260 /* Like register_specialization, but for local declarations. We are
1261 registering SPEC, an instantiation of TMPL. */
1264 register_local_specialization (tree spec, tree tmpl)
1268 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1269 htab_hash_pointer (tmpl), INSERT);
1270 *slot = build_tree_list (spec, tmpl);
1273 /* Print the list of candidate FNS in an error message. */
1276 print_candidates (tree fns)
1280 const char *str = "candidates are:";
1282 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1286 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1287 error ("%s %+#D", str, OVL_CURRENT (f));
1292 /* Returns the template (one of the functions given by TEMPLATE_ID)
1293 which can be specialized to match the indicated DECL with the
1294 explicit template args given in TEMPLATE_ID. The DECL may be
1295 NULL_TREE if none is available. In that case, the functions in
1296 TEMPLATE_ID are non-members.
1298 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1299 specialization of a member template.
1301 The TEMPLATE_COUNT is the number of references to qualifying
1302 template classes that appeared in the name of the function. See
1303 check_explicit_specialization for a more accurate description.
1305 The template args (those explicitly specified and those deduced)
1306 are output in a newly created vector *TARGS_OUT.
1308 If it is impossible to determine the result, an error message is
1309 issued. The error_mark_node is returned to indicate failure. */
1312 determine_specialization (tree template_id,
1315 int need_member_template,
1320 tree explicit_targs;
1321 tree candidates = NULL_TREE;
1322 tree templates = NULL_TREE;
1324 struct cp_binding_level *b;
1326 *targs_out = NULL_TREE;
1328 if (template_id == error_mark_node)
1329 return error_mark_node;
1331 fns = TREE_OPERAND (template_id, 0);
1332 explicit_targs = TREE_OPERAND (template_id, 1);
1334 if (fns == error_mark_node)
1335 return error_mark_node;
1337 /* Check for baselinks. */
1338 if (BASELINK_P (fns))
1339 fns = BASELINK_FUNCTIONS (fns);
1341 if (!is_overloaded_fn (fns))
1343 error ("%qD is not a function template", fns);
1344 return error_mark_node;
1347 /* Count the number of template headers specified for this
1350 for (b = current_binding_level;
1351 b->kind == sk_template_parms;
1355 for (; fns; fns = OVL_NEXT (fns))
1357 tree fn = OVL_CURRENT (fns);
1359 if (TREE_CODE (fn) == TEMPLATE_DECL)
1361 tree decl_arg_types;
1364 /* DECL might be a specialization of FN. */
1366 /* Adjust the type of DECL in case FN is a static member. */
1367 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1368 if (DECL_STATIC_FUNCTION_P (fn)
1369 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1370 decl_arg_types = TREE_CHAIN (decl_arg_types);
1372 /* Check that the number of function parameters matches.
1374 template <class T> void f(int i = 0);
1375 template <> void f<int>();
1376 The specialization f<int> is invalid but is not caught
1377 by get_bindings below. */
1379 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1380 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1383 /* For a non-static member function, we need to make sure that
1384 the const qualification is the same. This can be done by
1385 checking the 'this' in the argument list. */
1386 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1387 && !same_type_p (TREE_VALUE (fn_arg_types),
1388 TREE_VALUE (decl_arg_types)))
1391 /* In case of explicit specialization, we need to check if
1392 the number of template headers appearing in the specialization
1393 is correct. This is usually done in check_explicit_specialization,
1394 but the check done there cannot be exhaustive when specializing
1395 member functions. Consider the following code:
1397 template <> void A<int>::f(int);
1398 template <> template <> void A<int>::f(int);
1400 Assuming that A<int> is not itself an explicit specialization
1401 already, the first line specializes "f" which is a non-template
1402 member function, whilst the second line specializes "f" which
1403 is a template member function. So both lines are syntactically
1404 correct, and check_explicit_specialization does not reject
1407 Here, we can do better, as we are matching the specialization
1408 against the declarations. We count the number of template
1409 headers, and we check if they match TEMPLATE_COUNT + 1
1410 (TEMPLATE_COUNT is the number of qualifying template classes,
1411 plus there must be another header for the member template
1414 Notice that if header_count is zero, this is not a
1415 specialization but rather a template instantiation, so there
1416 is no check we can perform here. */
1417 if (header_count && header_count != template_count + 1)
1420 /* Check that the number of template arguments at the
1421 innermost level for DECL is the same as for FN. */
1422 if (current_binding_level->kind == sk_template_parms
1423 && !current_binding_level->explicit_spec_p
1424 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1425 != TREE_VEC_LENGTH (TREE_VALUE (current_template_parms))))
1428 /* See whether this function might be a specialization of this
1430 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1433 /* We cannot deduce template arguments that when used to
1434 specialize TMPL will produce DECL. */
1437 /* Save this template, and the arguments deduced. */
1438 templates = tree_cons (targs, fn, templates);
1440 else if (need_member_template)
1441 /* FN is an ordinary member function, and we need a
1442 specialization of a member template. */
1444 else if (TREE_CODE (fn) != FUNCTION_DECL)
1445 /* We can get IDENTIFIER_NODEs here in certain erroneous
1448 else if (!DECL_FUNCTION_MEMBER_P (fn))
1449 /* This is just an ordinary non-member function. Nothing can
1450 be a specialization of that. */
1452 else if (DECL_ARTIFICIAL (fn))
1453 /* Cannot specialize functions that are created implicitly. */
1457 tree decl_arg_types;
1459 /* This is an ordinary member function. However, since
1460 we're here, we can assume it's enclosing class is a
1461 template class. For example,
1463 template <typename T> struct S { void f(); };
1464 template <> void S<int>::f() {}
1466 Here, S<int>::f is a non-template, but S<int> is a
1467 template class. If FN has the same type as DECL, we
1468 might be in business. */
1470 if (!DECL_TEMPLATE_INFO (fn))
1471 /* Its enclosing class is an explicit specialization
1472 of a template class. This is not a candidate. */
1475 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1476 TREE_TYPE (TREE_TYPE (fn))))
1477 /* The return types differ. */
1480 /* Adjust the type of DECL in case FN is a static member. */
1481 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1482 if (DECL_STATIC_FUNCTION_P (fn)
1483 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1484 decl_arg_types = TREE_CHAIN (decl_arg_types);
1486 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1489 candidates = tree_cons (NULL_TREE, fn, candidates);
1493 if (templates && TREE_CHAIN (templates))
1499 It is possible for a specialization with a given function
1500 signature to be instantiated from more than one function
1501 template. In such cases, explicit specification of the
1502 template arguments must be used to uniquely identify the
1503 function template specialization being specialized.
1505 Note that here, there's no suggestion that we're supposed to
1506 determine which of the candidate templates is most
1507 specialized. However, we, also have:
1511 Partial ordering of overloaded function template
1512 declarations is used in the following contexts to select
1513 the function template to which a function template
1514 specialization refers:
1516 -- when an explicit specialization refers to a function
1519 So, we do use the partial ordering rules, at least for now.
1520 This extension can only serve to make invalid programs valid,
1521 so it's safe. And, there is strong anecdotal evidence that
1522 the committee intended the partial ordering rules to apply;
1523 the EDG front-end has that behavior, and John Spicer claims
1524 that the committee simply forgot to delete the wording in
1525 [temp.expl.spec]. */
1526 tree tmpl = most_specialized (templates, decl, explicit_targs);
1527 if (tmpl && tmpl != error_mark_node)
1529 targs = get_bindings (tmpl, decl, explicit_targs, /*check_ret=*/true);
1530 templates = tree_cons (targs, tmpl, NULL_TREE);
1534 if (templates == NULL_TREE && candidates == NULL_TREE)
1536 error ("template-id %qD for %q+D does not match any template "
1537 "declaration", template_id, decl);
1538 return error_mark_node;
1540 else if ((templates && TREE_CHAIN (templates))
1541 || (candidates && TREE_CHAIN (candidates))
1542 || (templates && candidates))
1544 error ("ambiguous template specialization %qD for %q+D",
1546 chainon (candidates, templates);
1547 print_candidates (candidates);
1548 return error_mark_node;
1551 /* We have one, and exactly one, match. */
1554 /* It was a specialization of an ordinary member function in a
1556 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1557 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1560 /* It was a specialization of a template. */
1561 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1562 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1564 *targs_out = copy_node (targs);
1565 SET_TMPL_ARGS_LEVEL (*targs_out,
1566 TMPL_ARGS_DEPTH (*targs_out),
1567 TREE_PURPOSE (templates));
1570 *targs_out = TREE_PURPOSE (templates);
1571 return TREE_VALUE (templates);
1574 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1575 but with the default argument values filled in from those in the
1579 copy_default_args_to_explicit_spec_1 (tree spec_types,
1582 tree new_spec_types;
1587 if (spec_types == void_list_node)
1588 return void_list_node;
1590 /* Substitute into the rest of the list. */
1592 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1593 TREE_CHAIN (tmpl_types));
1595 /* Add the default argument for this parameter. */
1596 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1597 TREE_VALUE (spec_types),
1601 /* DECL is an explicit specialization. Replicate default arguments
1602 from the template it specializes. (That way, code like:
1604 template <class T> void f(T = 3);
1605 template <> void f(double);
1608 works, as required.) An alternative approach would be to look up
1609 the correct default arguments at the call-site, but this approach
1610 is consistent with how implicit instantiations are handled. */
1613 copy_default_args_to_explicit_spec (tree decl)
1618 tree new_spec_types;
1622 tree object_type = NULL_TREE;
1623 tree in_charge = NULL_TREE;
1624 tree vtt = NULL_TREE;
1626 /* See if there's anything we need to do. */
1627 tmpl = DECL_TI_TEMPLATE (decl);
1628 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1629 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1630 if (TREE_PURPOSE (t))
1635 old_type = TREE_TYPE (decl);
1636 spec_types = TYPE_ARG_TYPES (old_type);
1638 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1640 /* Remove the this pointer, but remember the object's type for
1642 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1643 spec_types = TREE_CHAIN (spec_types);
1644 tmpl_types = TREE_CHAIN (tmpl_types);
1646 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1648 /* DECL may contain more parameters than TMPL due to the extra
1649 in-charge parameter in constructors and destructors. */
1650 in_charge = spec_types;
1651 spec_types = TREE_CHAIN (spec_types);
1653 if (DECL_HAS_VTT_PARM_P (decl))
1656 spec_types = TREE_CHAIN (spec_types);
1660 /* Compute the merged default arguments. */
1662 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1664 /* Compute the new FUNCTION_TYPE. */
1668 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1673 /* Put the in-charge parameter back. */
1674 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1675 TREE_VALUE (in_charge),
1678 new_type = build_method_type_directly (object_type,
1679 TREE_TYPE (old_type),
1683 new_type = build_function_type (TREE_TYPE (old_type),
1685 new_type = cp_build_type_attribute_variant (new_type,
1686 TYPE_ATTRIBUTES (old_type));
1687 new_type = build_exception_variant (new_type,
1688 TYPE_RAISES_EXCEPTIONS (old_type));
1689 TREE_TYPE (decl) = new_type;
1692 /* Check to see if the function just declared, as indicated in
1693 DECLARATOR, and in DECL, is a specialization of a function
1694 template. We may also discover that the declaration is an explicit
1695 instantiation at this point.
1697 Returns DECL, or an equivalent declaration that should be used
1698 instead if all goes well. Issues an error message if something is
1699 amiss. Returns error_mark_node if the error is not easily
1702 FLAGS is a bitmask consisting of the following flags:
1704 2: The function has a definition.
1705 4: The function is a friend.
1707 The TEMPLATE_COUNT is the number of references to qualifying
1708 template classes that appeared in the name of the function. For
1711 template <class T> struct S { void f(); };
1714 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1715 classes are not counted in the TEMPLATE_COUNT, so that in
1717 template <class T> struct S {};
1718 template <> struct S<int> { void f(); }
1719 template <> void S<int>::f();
1721 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1722 invalid; there should be no template <>.)
1724 If the function is a specialization, it is marked as such via
1725 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1726 is set up correctly, and it is added to the list of specializations
1727 for that template. */
1730 check_explicit_specialization (tree declarator,
1735 int have_def = flags & 2;
1736 int is_friend = flags & 4;
1737 int specialization = 0;
1738 int explicit_instantiation = 0;
1739 int member_specialization = 0;
1740 tree ctype = DECL_CLASS_CONTEXT (decl);
1741 tree dname = DECL_NAME (decl);
1746 if (!processing_specialization)
1749 tsk = tsk_excessive_parms;
1752 tsk = current_tmpl_spec_kind (template_count);
1757 if (processing_specialization)
1760 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1762 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1765 /* This could be something like:
1767 template <class T> void f(T);
1768 class S { friend void f<>(int); } */
1772 /* This case handles bogus declarations like template <>
1773 template <class T> void f<int>(); */
1775 error ("template-id %qD in declaration of primary template",
1782 case tsk_invalid_member_spec:
1783 /* The error has already been reported in
1784 check_specialization_scope. */
1785 return error_mark_node;
1787 case tsk_invalid_expl_inst:
1788 error ("template parameter list used in explicit instantiation");
1794 error ("definition provided for explicit instantiation");
1796 explicit_instantiation = 1;
1799 case tsk_excessive_parms:
1800 case tsk_insufficient_parms:
1801 if (tsk == tsk_excessive_parms)
1802 error ("too many template parameter lists in declaration of %qD",
1804 else if (template_header_count)
1805 error("too few template parameter lists in declaration of %qD", decl);
1807 error("explicit specialization of %qD must be introduced by "
1808 "%<template <>%>", decl);
1812 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1814 member_specialization = 1;
1820 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1822 /* This case handles bogus declarations like template <>
1823 template <class T> void f<int>(); */
1825 if (uses_template_parms (declarator))
1826 error ("function template partial specialization %qD "
1827 "is not allowed", declarator);
1829 error ("template-id %qD in declaration of primary template",
1834 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1835 /* This is a specialization of a member template, without
1836 specialization the containing class. Something like:
1838 template <class T> struct S {
1839 template <class U> void f (U);
1841 template <> template <class U> void S<int>::f(U) {}
1843 That's a specialization -- but of the entire template. */
1851 if (specialization || member_specialization)
1853 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1854 for (; t; t = TREE_CHAIN (t))
1855 if (TREE_PURPOSE (t))
1858 ("default argument specified in explicit specialization");
1861 if (current_lang_name == lang_name_c)
1862 error ("template specialization with C linkage");
1865 if (specialization || member_specialization || explicit_instantiation)
1867 tree tmpl = NULL_TREE;
1868 tree targs = NULL_TREE;
1870 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1871 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1875 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1880 /* If there is no class context, the explicit instantiation
1881 must be at namespace scope. */
1882 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1884 /* Find the namespace binding, using the declaration
1886 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1887 if (!fns || !is_overloaded_fn (fns))
1889 error ("%qD is not a template function", dname);
1890 fns = error_mark_node;
1894 declarator = lookup_template_function (fns, NULL_TREE);
1897 if (declarator == error_mark_node)
1898 return error_mark_node;
1900 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1902 if (!explicit_instantiation)
1903 /* A specialization in class scope. This is invalid,
1904 but the error will already have been flagged by
1905 check_specialization_scope. */
1906 return error_mark_node;
1909 /* It's not valid to write an explicit instantiation in
1912 class C { template void f(); }
1914 This case is caught by the parser. However, on
1917 template class C { void f(); };
1919 (which is invalid) we can get here. The error will be
1926 else if (ctype != NULL_TREE
1927 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1930 /* Find the list of functions in ctype that have the same
1931 name as the declared function. */
1932 tree name = TREE_OPERAND (declarator, 0);
1933 tree fns = NULL_TREE;
1936 if (constructor_name_p (name, ctype))
1938 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1940 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1941 : !CLASSTYPE_DESTRUCTORS (ctype))
1943 /* From [temp.expl.spec]:
1945 If such an explicit specialization for the member
1946 of a class template names an implicitly-declared
1947 special member function (clause _special_), the
1948 program is ill-formed.
1950 Similar language is found in [temp.explicit]. */
1951 error ("specialization of implicitly-declared special member function");
1952 return error_mark_node;
1955 name = is_constructor ? ctor_identifier : dtor_identifier;
1958 if (!DECL_CONV_FN_P (decl))
1960 idx = lookup_fnfields_1 (ctype, name);
1962 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1966 VEC(tree,gc) *methods;
1969 /* For a type-conversion operator, we cannot do a
1970 name-based lookup. We might be looking for `operator
1971 int' which will be a specialization of `operator T'.
1972 So, we find *all* the conversion operators, and then
1973 select from them. */
1976 methods = CLASSTYPE_METHOD_VEC (ctype);
1978 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1979 VEC_iterate (tree, methods, idx, ovl);
1982 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
1983 /* There are no more conversion functions. */
1986 /* Glue all these conversion functions together
1987 with those we already have. */
1988 for (; ovl; ovl = OVL_NEXT (ovl))
1989 fns = ovl_cons (OVL_CURRENT (ovl), fns);
1993 if (fns == NULL_TREE)
1995 error ("no member function %qD declared in %qT", name, ctype);
1996 return error_mark_node;
1999 TREE_OPERAND (declarator, 0) = fns;
2002 /* Figure out what exactly is being specialized at this point.
2003 Note that for an explicit instantiation, even one for a
2004 member function, we cannot tell apriori whether the
2005 instantiation is for a member template, or just a member
2006 function of a template class. Even if a member template is
2007 being instantiated, the member template arguments may be
2008 elided if they can be deduced from the rest of the
2010 tmpl = determine_specialization (declarator, decl,
2012 member_specialization,
2015 if (!tmpl || tmpl == error_mark_node)
2016 /* We couldn't figure out what this declaration was
2018 return error_mark_node;
2021 tree gen_tmpl = most_general_template (tmpl);
2023 if (explicit_instantiation)
2025 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2026 is done by do_decl_instantiation later. */
2028 int arg_depth = TMPL_ARGS_DEPTH (targs);
2029 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2031 if (arg_depth > parm_depth)
2033 /* If TMPL is not the most general template (for
2034 example, if TMPL is a friend template that is
2035 injected into namespace scope), then there will
2036 be too many levels of TARGS. Remove some of them
2041 new_targs = make_tree_vec (parm_depth);
2042 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2043 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2044 = TREE_VEC_ELT (targs, i);
2048 return instantiate_template (tmpl, targs, tf_error);
2051 /* If we thought that the DECL was a member function, but it
2052 turns out to be specializing a static member function,
2053 make DECL a static member function as well. */
2054 if (DECL_STATIC_FUNCTION_P (tmpl)
2055 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2056 revert_static_member_fn (decl);
2058 /* If this is a specialization of a member template of a
2059 template class. In we want to return the TEMPLATE_DECL,
2060 not the specialization of it. */
2061 if (tsk == tsk_template)
2063 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2064 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2067 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2068 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2069 = DECL_SOURCE_LOCATION (decl);
2070 /* We want to use the argument list specified in the
2071 definition, not in the original declaration. */
2072 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2073 = DECL_ARGUMENTS (decl);
2078 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2079 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2081 /* Inherit default function arguments from the template
2082 DECL is specializing. */
2083 copy_default_args_to_explicit_spec (decl);
2085 /* This specialization has the same protection as the
2086 template it specializes. */
2087 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2088 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2090 /* The specialization has the same visibility as the
2091 template it specializes. */
2092 if (DECL_VISIBILITY_SPECIFIED (gen_tmpl))
2094 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2095 DECL_VISIBILITY (decl) = DECL_VISIBILITY (gen_tmpl);
2098 if (is_friend && !have_def)
2099 /* This is not really a declaration of a specialization.
2100 It's just the name of an instantiation. But, it's not
2101 a request for an instantiation, either. */
2102 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2103 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2104 /* This is indeed a specialization. In case of constructors
2105 and destructors, we need in-charge and not-in-charge
2106 versions in V3 ABI. */
2107 clone_function_decl (decl, /*update_method_vec_p=*/0);
2109 /* Register this specialization so that we can find it
2111 decl = register_specialization (decl, gen_tmpl, targs);
2118 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2119 parameters. These are represented in the same format used for
2120 DECL_TEMPLATE_PARMS. */
2123 comp_template_parms (tree parms1, tree parms2)
2128 if (parms1 == parms2)
2131 for (p1 = parms1, p2 = parms2;
2132 p1 != NULL_TREE && p2 != NULL_TREE;
2133 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2135 tree t1 = TREE_VALUE (p1);
2136 tree t2 = TREE_VALUE (p2);
2139 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2140 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2142 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2145 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2147 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2148 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2150 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2153 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2155 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2160 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2161 /* One set of parameters has more parameters lists than the
2168 /* Complain if DECL shadows a template parameter.
2170 [temp.local]: A template-parameter shall not be redeclared within its
2171 scope (including nested scopes). */
2174 check_template_shadow (tree decl)
2178 /* If we're not in a template, we can't possibly shadow a template
2180 if (!current_template_parms)
2183 /* Figure out what we're shadowing. */
2184 if (TREE_CODE (decl) == OVERLOAD)
2185 decl = OVL_CURRENT (decl);
2186 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2188 /* If there's no previous binding for this name, we're not shadowing
2189 anything, let alone a template parameter. */
2193 /* If we're not shadowing a template parameter, we're done. Note
2194 that OLDDECL might be an OVERLOAD (or perhaps even an
2195 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2197 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2200 /* We check for decl != olddecl to avoid bogus errors for using a
2201 name inside a class. We check TPFI to avoid duplicate errors for
2202 inline member templates. */
2204 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2207 error ("declaration of %q+#D", decl);
2208 error (" shadows template parm %q+#D", olddecl);
2211 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2212 ORIG_LEVEL, DECL, and TYPE. */
2215 build_template_parm_index (int index,
2221 tree t = make_node (TEMPLATE_PARM_INDEX);
2222 TEMPLATE_PARM_IDX (t) = index;
2223 TEMPLATE_PARM_LEVEL (t) = level;
2224 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2225 TEMPLATE_PARM_DECL (t) = decl;
2226 TREE_TYPE (t) = type;
2227 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2228 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2229 TREE_READONLY (t) = TREE_READONLY (decl);
2234 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2235 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2236 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2237 new one is created. */
2240 reduce_template_parm_level (tree index, tree type, int levels)
2242 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2243 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2244 != TEMPLATE_PARM_LEVEL (index) - levels))
2246 tree orig_decl = TEMPLATE_PARM_DECL (index);
2249 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2250 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2251 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2252 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2253 DECL_ARTIFICIAL (decl) = 1;
2254 SET_DECL_TEMPLATE_PARM_P (decl);
2256 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2257 TEMPLATE_PARM_LEVEL (index) - levels,
2258 TEMPLATE_PARM_ORIG_LEVEL (index),
2260 TEMPLATE_PARM_DESCENDANTS (index) = t;
2262 /* Template template parameters need this. */
2263 if (TREE_CODE (decl) != CONST_DECL)
2264 DECL_TEMPLATE_PARMS (decl)
2265 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2268 return TEMPLATE_PARM_DESCENDANTS (index);
2271 /* Process information from new template parameter NEXT and append it to the
2272 LIST being built. This new parameter is a non-type parameter iff
2273 IS_NON_TYPE is true. */
2276 process_template_parm (tree list, tree next, bool is_non_type)
2284 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2285 defval = TREE_PURPOSE (parm);
2289 tree p = TREE_VALUE (tree_last (list));
2291 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2292 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2294 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2302 parm = TREE_VALUE (parm);
2304 SET_DECL_TEMPLATE_PARM_P (parm);
2308 The top-level cv-qualifiers on the template-parameter are
2309 ignored when determining its type. */
2310 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2312 /* A template parameter is not modifiable. */
2313 TREE_CONSTANT (parm) = 1;
2314 TREE_INVARIANT (parm) = 1;
2315 TREE_READONLY (parm) = 1;
2316 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2317 TREE_TYPE (parm) = void_type_node;
2318 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2319 TREE_CONSTANT (decl) = 1;
2320 TREE_INVARIANT (decl) = 1;
2321 TREE_READONLY (decl) = 1;
2322 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2323 = build_template_parm_index (idx, processing_template_decl,
2324 processing_template_decl,
2325 decl, TREE_TYPE (parm));
2330 parm = TREE_VALUE (TREE_VALUE (parm));
2332 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2334 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2335 /* This is for distinguishing between real templates and template
2336 template parameters */
2337 TREE_TYPE (parm) = t;
2338 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2343 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2344 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2345 decl = build_decl (TYPE_DECL, parm, t);
2348 TYPE_NAME (t) = decl;
2349 TYPE_STUB_DECL (t) = decl;
2351 TEMPLATE_TYPE_PARM_INDEX (t)
2352 = build_template_parm_index (idx, processing_template_decl,
2353 processing_template_decl,
2354 decl, TREE_TYPE (parm));
2356 DECL_ARTIFICIAL (decl) = 1;
2357 SET_DECL_TEMPLATE_PARM_P (decl);
2359 parm = build_tree_list (defval, parm);
2360 return chainon (list, parm);
2363 /* The end of a template parameter list has been reached. Process the
2364 tree list into a parameter vector, converting each parameter into a more
2365 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2369 end_template_parm_list (tree parms)
2373 tree saved_parmlist = make_tree_vec (list_length (parms));
2375 current_template_parms
2376 = tree_cons (size_int (processing_template_decl),
2377 saved_parmlist, current_template_parms);
2379 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2381 next = TREE_CHAIN (parm);
2382 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2383 TREE_CHAIN (parm) = NULL_TREE;
2386 --processing_template_parmlist;
2388 return saved_parmlist;
2391 /* end_template_decl is called after a template declaration is seen. */
2394 end_template_decl (void)
2396 reset_specialization ();
2398 if (! processing_template_decl)
2401 /* This matches the pushlevel in begin_template_parm_list. */
2404 --processing_template_decl;
2405 current_template_parms = TREE_CHAIN (current_template_parms);
2408 /* Given a template argument vector containing the template PARMS.
2409 The innermost PARMS are given first. */
2412 current_template_args (void)
2415 tree args = NULL_TREE;
2416 int length = TMPL_PARMS_DEPTH (current_template_parms);
2419 /* If there is only one level of template parameters, we do not
2420 create a TREE_VEC of TREE_VECs. Instead, we return a single
2421 TREE_VEC containing the arguments. */
2423 args = make_tree_vec (length);
2425 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2427 tree a = copy_node (TREE_VALUE (header));
2430 TREE_TYPE (a) = NULL_TREE;
2431 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2433 tree t = TREE_VEC_ELT (a, i);
2435 /* T will be a list if we are called from within a
2436 begin/end_template_parm_list pair, but a vector directly
2437 if within a begin/end_member_template_processing pair. */
2438 if (TREE_CODE (t) == TREE_LIST)
2442 if (TREE_CODE (t) == TYPE_DECL
2443 || TREE_CODE (t) == TEMPLATE_DECL)
2446 t = DECL_INITIAL (t);
2447 TREE_VEC_ELT (a, i) = t;
2452 TREE_VEC_ELT (args, --l) = a;
2460 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2461 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2462 a member template. Used by push_template_decl below. */
2465 build_template_decl (tree decl, tree parms, bool member_template_p)
2467 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2468 DECL_TEMPLATE_PARMS (tmpl) = parms;
2469 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2470 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2471 if (DECL_LANG_SPECIFIC (decl))
2473 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2474 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2475 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2476 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2477 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2478 if (DECL_OVERLOADED_OPERATOR_P (decl))
2479 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2480 DECL_OVERLOADED_OPERATOR_P (decl));
2486 struct template_parm_data
2488 /* The level of the template parameters we are currently
2492 /* The index of the specialization argument we are currently
2496 /* An array whose size is the number of template parameters. The
2497 elements are nonzero if the parameter has been used in any one
2498 of the arguments processed so far. */
2501 /* An array whose size is the number of template arguments. The
2502 elements are nonzero if the argument makes use of template
2503 parameters of this level. */
2504 int* arg_uses_template_parms;
2507 /* Subroutine of push_template_decl used to see if each template
2508 parameter in a partial specialization is used in the explicit
2509 argument list. If T is of the LEVEL given in DATA (which is
2510 treated as a template_parm_data*), then DATA->PARMS is marked
2514 mark_template_parm (tree t, void* data)
2518 struct template_parm_data* tpd = (struct template_parm_data*) data;
2520 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2522 level = TEMPLATE_PARM_LEVEL (t);
2523 idx = TEMPLATE_PARM_IDX (t);
2527 level = TEMPLATE_TYPE_LEVEL (t);
2528 idx = TEMPLATE_TYPE_IDX (t);
2531 if (level == tpd->level)
2533 tpd->parms[idx] = 1;
2534 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2537 /* Return zero so that for_each_template_parm will continue the
2538 traversal of the tree; we want to mark *every* template parm. */
2542 /* Process the partial specialization DECL. */
2545 process_partial_specialization (tree decl)
2547 tree type = TREE_TYPE (decl);
2548 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2549 tree specargs = CLASSTYPE_TI_ARGS (type);
2550 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2551 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2552 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2553 int nargs = TREE_VEC_LENGTH (inner_args);
2554 int ntparms = TREE_VEC_LENGTH (inner_parms);
2556 int did_error_intro = 0;
2557 struct template_parm_data tpd;
2558 struct template_parm_data tpd2;
2560 /* We check that each of the template parameters given in the
2561 partial specialization is used in the argument list to the
2562 specialization. For example:
2564 template <class T> struct S;
2565 template <class T> struct S<T*>;
2567 The second declaration is OK because `T*' uses the template
2568 parameter T, whereas
2570 template <class T> struct S<int>;
2572 is no good. Even trickier is:
2583 The S2<T> declaration is actually invalid; it is a
2584 full-specialization. Of course,
2587 struct S2<T (*)(U)>;
2589 or some such would have been OK. */
2590 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2591 tpd.parms = alloca (sizeof (int) * ntparms);
2592 memset (tpd.parms, 0, sizeof (int) * ntparms);
2594 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2595 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2596 for (i = 0; i < nargs; ++i)
2598 tpd.current_arg = i;
2599 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2600 &mark_template_parm,
2604 for (i = 0; i < ntparms; ++i)
2605 if (tpd.parms[i] == 0)
2607 /* One of the template parms was not used in the
2609 if (!did_error_intro)
2611 error ("template parameters not used in partial specialization:");
2612 did_error_intro = 1;
2615 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2618 /* [temp.class.spec]
2620 The argument list of the specialization shall not be identical to
2621 the implicit argument list of the primary template. */
2622 if (comp_template_args
2624 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2626 error ("partial specialization %qT does not specialize any template arguments", type);
2628 /* [temp.class.spec]
2630 A partially specialized non-type argument expression shall not
2631 involve template parameters of the partial specialization except
2632 when the argument expression is a simple identifier.
2634 The type of a template parameter corresponding to a specialized
2635 non-type argument shall not be dependent on a parameter of the
2637 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2639 for (i = 0; i < nargs; ++i)
2641 tree arg = TREE_VEC_ELT (inner_args, i);
2642 if (/* These first two lines are the `non-type' bit. */
2644 && TREE_CODE (arg) != TEMPLATE_DECL
2645 /* This next line is the `argument expression is not just a
2646 simple identifier' condition and also the `specialized
2647 non-type argument' bit. */
2648 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2650 if (tpd.arg_uses_template_parms[i])
2651 error ("template argument %qE involves template parameter(s)", arg);
2654 /* Look at the corresponding template parameter,
2655 marking which template parameters its type depends
2658 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2663 /* We haven't yet initialized TPD2. Do so now. */
2664 tpd2.arg_uses_template_parms
2665 = alloca (sizeof (int) * nargs);
2666 /* The number of parameters here is the number in the
2667 main template, which, as checked in the assertion
2669 tpd2.parms = alloca (sizeof (int) * nargs);
2671 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2674 /* Mark the template parameters. But this time, we're
2675 looking for the template parameters of the main
2676 template, not in the specialization. */
2677 tpd2.current_arg = i;
2678 tpd2.arg_uses_template_parms[i] = 0;
2679 memset (tpd2.parms, 0, sizeof (int) * nargs);
2680 for_each_template_parm (type,
2681 &mark_template_parm,
2685 if (tpd2.arg_uses_template_parms [i])
2687 /* The type depended on some template parameters.
2688 If they are fully specialized in the
2689 specialization, that's OK. */
2691 for (j = 0; j < nargs; ++j)
2692 if (tpd2.parms[j] != 0
2693 && tpd.arg_uses_template_parms [j])
2695 error ("type %qT of template argument %qE depends "
2696 "on template parameter(s)",
2706 if (retrieve_specialization (maintmpl, specargs,
2707 /*class_specializations_p=*/true))
2708 /* We've already got this specialization. */
2711 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2712 = tree_cons (inner_args, inner_parms,
2713 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2714 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2718 /* Check that a template declaration's use of default arguments is not
2719 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2720 nonzero if DECL is the thing declared by a primary template.
2721 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2724 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2727 int last_level_to_check;
2732 A default template-argument shall not be specified in a
2733 function template declaration or a function template definition, nor
2734 in the template-parameter-list of the definition of a member of a
2737 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2738 /* You can't have a function template declaration in a local
2739 scope, nor you can you define a member of a class template in a
2743 if (current_class_type
2744 && !TYPE_BEING_DEFINED (current_class_type)
2745 && DECL_LANG_SPECIFIC (decl)
2746 /* If this is either a friend defined in the scope of the class
2747 or a member function. */
2748 && (DECL_FUNCTION_MEMBER_P (decl)
2749 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2750 : DECL_FRIEND_CONTEXT (decl)
2751 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2753 /* And, if it was a member function, it really was defined in
2754 the scope of the class. */
2755 && (!DECL_FUNCTION_MEMBER_P (decl)
2756 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2757 /* We already checked these parameters when the template was
2758 declared, so there's no need to do it again now. This function
2759 was defined in class scope, but we're processing it's body now
2760 that the class is complete. */
2765 If a template-parameter has a default template-argument, all
2766 subsequent template-parameters shall have a default
2767 template-argument supplied. */
2768 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2770 tree inner_parms = TREE_VALUE (parm_level);
2771 int ntparms = TREE_VEC_LENGTH (inner_parms);
2772 int seen_def_arg_p = 0;
2775 for (i = 0; i < ntparms; ++i)
2777 tree parm = TREE_VEC_ELT (inner_parms, i);
2778 if (TREE_PURPOSE (parm))
2780 else if (seen_def_arg_p)
2782 error ("no default argument for %qD", TREE_VALUE (parm));
2783 /* For better subsequent error-recovery, we indicate that
2784 there should have been a default argument. */
2785 TREE_PURPOSE (parm) = error_mark_node;
2790 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2791 /* For an ordinary class template, default template arguments are
2792 allowed at the innermost level, e.g.:
2793 template <class T = int>
2795 but, in a partial specialization, they're not allowed even
2796 there, as we have in [temp.class.spec]:
2798 The template parameter list of a specialization shall not
2799 contain default template argument values.
2801 So, for a partial specialization, or for a function template,
2802 we look at all of them. */
2805 /* But, for a primary class template that is not a partial
2806 specialization we look at all template parameters except the
2808 parms = TREE_CHAIN (parms);
2810 /* Figure out what error message to issue. */
2811 if (TREE_CODE (decl) == FUNCTION_DECL)
2812 msg = "default template arguments may not be used in function templates";
2813 else if (is_partial)
2814 msg = "default template arguments may not be used in partial specializations";
2816 msg = "default argument for template parameter for class enclosing %qD";
2818 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2819 /* If we're inside a class definition, there's no need to
2820 examine the parameters to the class itself. On the one
2821 hand, they will be checked when the class is defined, and,
2822 on the other, default arguments are valid in things like:
2823 template <class T = double>
2824 struct S { template <class U> void f(U); };
2825 Here the default argument for `S' has no bearing on the
2826 declaration of `f'. */
2827 last_level_to_check = template_class_depth (current_class_type) + 1;
2829 /* Check everything. */
2830 last_level_to_check = 0;
2832 for (parm_level = parms;
2833 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2834 parm_level = TREE_CHAIN (parm_level))
2836 tree inner_parms = TREE_VALUE (parm_level);
2840 ntparms = TREE_VEC_LENGTH (inner_parms);
2841 for (i = 0; i < ntparms; ++i)
2842 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2850 /* Clear out the default argument so that we are not
2852 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2855 /* At this point, if we're still interested in issuing messages,
2856 they must apply to classes surrounding the object declared. */
2858 msg = "default argument for template parameter for class enclosing %qD";
2862 /* Worker for push_template_decl_real, called via
2863 for_each_template_parm. DATA is really an int, indicating the
2864 level of the parameters we are interested in. If T is a template
2865 parameter of that level, return nonzero. */
2868 template_parm_this_level_p (tree t, void* data)
2870 int this_level = *(int *)data;
2873 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2874 level = TEMPLATE_PARM_LEVEL (t);
2876 level = TEMPLATE_TYPE_LEVEL (t);
2877 return level == this_level;
2880 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2881 parameters given by current_template_args, or reuses a
2882 previously existing one, if appropriate. Returns the DECL, or an
2883 equivalent one, if it is replaced via a call to duplicate_decls.
2885 If IS_FRIEND is nonzero, DECL is a friend declaration. */
2888 push_template_decl_real (tree decl, int is_friend)
2896 int new_template_p = 0;
2897 /* True if the template is a member template, in the sense of
2899 bool member_template_p = false;
2901 if (decl == error_mark_node)
2904 /* See if this is a partial specialization. */
2905 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2906 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2907 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2909 is_friend |= (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl));
2912 /* For a friend, we want the context of the friend function, not
2913 the type of which it is a friend. */
2914 ctx = DECL_CONTEXT (decl);
2915 else if (CP_DECL_CONTEXT (decl)
2916 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2917 /* In the case of a virtual function, we want the class in which
2919 ctx = CP_DECL_CONTEXT (decl);
2921 /* Otherwise, if we're currently defining some class, the DECL
2922 is assumed to be a member of the class. */
2923 ctx = current_scope ();
2925 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2928 if (!DECL_CONTEXT (decl))
2929 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2931 /* See if this is a primary template. */
2932 primary = template_parm_scope_p ();
2936 if (DECL_CLASS_SCOPE_P (decl))
2937 member_template_p = true;
2938 if (current_lang_name == lang_name_c)
2939 error ("template with C linkage");
2940 else if (TREE_CODE (decl) == TYPE_DECL
2941 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2942 error ("template class without a name");
2943 else if (TREE_CODE (decl) == FUNCTION_DECL)
2945 if (DECL_DESTRUCTOR_P (decl))
2949 A destructor shall not be a member template. */
2950 error ("destructor %qD declared as member template", decl);
2951 return error_mark_node;
2953 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
2954 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
2955 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
2956 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
2957 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
2958 == void_list_node)))
2960 /* [basic.stc.dynamic.allocation]
2962 An allocation function can be a function
2963 template. ... Template allocation functions shall
2964 have two or more parameters. */
2965 error ("invalid template declaration of %qD", decl);
2969 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
2970 && CLASS_TYPE_P (TREE_TYPE (decl)))
2971 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx)))
2975 error ("template declaration of %q#D", decl);
2976 return error_mark_node;
2980 /* Check to see that the rules regarding the use of default
2981 arguments are not being violated. */
2982 check_default_tmpl_args (decl, current_template_parms,
2983 primary, is_partial);
2986 return process_partial_specialization (decl);
2988 args = current_template_args ();
2991 || TREE_CODE (ctx) == FUNCTION_DECL
2992 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
2993 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
2995 if (DECL_LANG_SPECIFIC (decl)
2996 && DECL_TEMPLATE_INFO (decl)
2997 && DECL_TI_TEMPLATE (decl))
2998 tmpl = DECL_TI_TEMPLATE (decl);
2999 /* If DECL is a TYPE_DECL for a class-template, then there won't
3000 be DECL_LANG_SPECIFIC. The information equivalent to
3001 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3002 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3003 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3004 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3006 /* Since a template declaration already existed for this
3007 class-type, we must be redeclaring it here. Make sure
3008 that the redeclaration is valid. */
3009 redeclare_class_template (TREE_TYPE (decl),
3010 current_template_parms);
3011 /* We don't need to create a new TEMPLATE_DECL; just use the
3012 one we already had. */
3013 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3017 tmpl = build_template_decl (decl, current_template_parms,
3021 if (DECL_LANG_SPECIFIC (decl)
3022 && DECL_TEMPLATE_SPECIALIZATION (decl))
3024 /* A specialization of a member template of a template
3026 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3027 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3028 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3034 tree a, t, current, parms;
3037 if (TREE_CODE (decl) == TYPE_DECL)
3039 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3040 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3041 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3042 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3043 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3046 error ("%qD does not declare a template type", decl);
3050 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3052 error ("template definition of non-template %q#D", decl);
3056 tmpl = DECL_TI_TEMPLATE (decl);
3058 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3059 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3060 && DECL_TEMPLATE_SPECIALIZATION (decl)
3061 && DECL_MEMBER_TEMPLATE_P (tmpl))
3065 /* The declaration is a specialization of a member
3066 template, declared outside the class. Therefore, the
3067 innermost template arguments will be NULL, so we
3068 replace them with the arguments determined by the
3069 earlier call to check_explicit_specialization. */
3070 args = DECL_TI_ARGS (decl);
3073 = build_template_decl (decl, current_template_parms,
3075 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3076 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3077 DECL_TI_TEMPLATE (decl) = new_tmpl;
3078 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3079 DECL_TEMPLATE_INFO (new_tmpl)
3080 = tree_cons (tmpl, args, NULL_TREE);
3082 register_specialization (new_tmpl,
3083 most_general_template (tmpl),
3088 /* Make sure the template headers we got make sense. */
3090 parms = DECL_TEMPLATE_PARMS (tmpl);
3091 i = TMPL_PARMS_DEPTH (parms);
3092 if (TMPL_ARGS_DEPTH (args) != i)
3094 error ("expected %d levels of template parms for %q#D, got %d",
3095 i, decl, TMPL_ARGS_DEPTH (args));
3098 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3100 a = TMPL_ARGS_LEVEL (args, i);
3101 t = INNERMOST_TEMPLATE_PARMS (parms);
3103 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3105 if (current == decl)
3106 error ("got %d template parameters for %q#D",
3107 TREE_VEC_LENGTH (a), decl);
3109 error ("got %d template parameters for %q#T",
3110 TREE_VEC_LENGTH (a), current);
3111 error (" but %d required", TREE_VEC_LENGTH (t));
3112 return error_mark_node;
3115 /* Perhaps we should also check that the parms are used in the
3116 appropriate qualifying scopes in the declarator? */
3118 if (current == decl)
3121 current = TYPE_CONTEXT (current);
3125 DECL_TEMPLATE_RESULT (tmpl) = decl;
3126 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3128 /* Push template declarations for global functions and types. Note
3129 that we do not try to push a global template friend declared in a
3130 template class; such a thing may well depend on the template
3131 parameters of the class. */
3132 if (new_template_p && !ctx
3133 && !(is_friend && template_class_depth (current_class_type) > 0))
3135 tmpl = pushdecl_namespace_level (tmpl);
3136 if (tmpl == error_mark_node)
3137 return error_mark_node;
3139 /* Hide template friend classes that haven't been declared yet. */
3140 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
3142 DECL_ANTICIPATED (tmpl) = 1;
3143 DECL_FRIEND_P (tmpl) = 1;
3149 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3150 if (DECL_CONV_FN_P (tmpl))
3152 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3154 /* It is a conversion operator. See if the type converted to
3155 depends on innermost template operands. */
3157 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3159 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3163 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3164 back to its most general template. If TMPL is a specialization,
3165 ARGS may only have the innermost set of arguments. Add the missing
3166 argument levels if necessary. */
3167 if (DECL_TEMPLATE_INFO (tmpl))
3168 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3170 info = tree_cons (tmpl, args, NULL_TREE);
3172 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3174 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3175 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3176 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3177 /* Don't change the name if we've already set it up. */
3178 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3179 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3181 else if (DECL_LANG_SPECIFIC (decl))
3182 DECL_TEMPLATE_INFO (decl) = info;
3184 return DECL_TEMPLATE_RESULT (tmpl);
3188 push_template_decl (tree decl)
3190 return push_template_decl_real (decl, 0);
3193 /* Called when a class template TYPE is redeclared with the indicated
3194 template PARMS, e.g.:
3196 template <class T> struct S;
3197 template <class T> struct S {}; */
3200 redeclare_class_template (tree type, tree parms)
3206 if (!TYPE_TEMPLATE_INFO (type))
3208 error ("%qT is not a template type", type);
3212 tmpl = TYPE_TI_TEMPLATE (type);
3213 if (!PRIMARY_TEMPLATE_P (tmpl))
3214 /* The type is nested in some template class. Nothing to worry
3215 about here; there are no new template parameters for the nested
3221 error ("template specifiers not specified in declaration of %qD",
3226 parms = INNERMOST_TEMPLATE_PARMS (parms);
3227 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3229 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3231 error ("previous declaration %q+D", tmpl);
3232 error ("used %d template parameter(s) instead of %d",
3233 TREE_VEC_LENGTH (tmpl_parms),
3234 TREE_VEC_LENGTH (parms));
3238 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3240 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3241 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3242 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3243 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3245 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3247 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3248 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3249 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3251 error ("template parameter %q+#D", tmpl_parm);
3252 error ("redeclared here as %q#D", parm);
3256 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3258 /* We have in [temp.param]:
3260 A template-parameter may not be given default arguments
3261 by two different declarations in the same scope. */
3262 error ("redefinition of default argument for %q#D", parm);
3263 error ("%J original definition appeared here", tmpl_parm);
3267 if (parm_default != NULL_TREE)
3268 /* Update the previous template parameters (which are the ones
3269 that will really count) with the new default value. */
3270 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3271 else if (tmpl_default != NULL_TREE)
3272 /* Update the new parameters, too; they'll be used as the
3273 parameters for any members. */
3274 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3278 /* Simplify EXPR if it is a non-dependent expression. Returns the
3279 (possibly simplified) expression. */
3282 fold_non_dependent_expr (tree expr)
3284 /* If we're in a template, but EXPR isn't value dependent, simplify
3285 it. We're supposed to treat:
3287 template <typename T> void f(T[1 + 1]);
3288 template <typename T> void f(T[2]);
3290 as two declarations of the same function, for example. */
3291 if (processing_template_decl
3292 && !type_dependent_expression_p (expr)
3293 && !value_dependent_expression_p (expr))
3295 HOST_WIDE_INT saved_processing_template_decl;
3297 saved_processing_template_decl = processing_template_decl;
3298 processing_template_decl = 0;
3299 expr = tsubst_copy_and_build (expr,
3302 /*in_decl=*/NULL_TREE,
3303 /*function_p=*/false);
3304 processing_template_decl = saved_processing_template_decl;
3309 /* EXPR is an expression which is used in a constant-expression context.
3310 For instance, it could be a VAR_DECL with a constant initializer.
3311 Extract the innest constant expression.
3313 This is basically a more powerful version of
3314 integral_constant_value, which can be used also in templates where
3315 initializers can maintain a syntactic rather than semantic form
3316 (even if they are non-dependent, for access-checking purposes). */
3319 fold_decl_constant_value (tree expr)
3321 tree const_expr = expr;
3324 expr = fold_non_dependent_expr (const_expr);
3325 const_expr = integral_constant_value (expr);
3327 while (expr != const_expr);
3332 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3333 must be a function or a pointer-to-function type, as specified
3334 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3335 and check that the resulting function has external linkage. */
3338 convert_nontype_argument_function (tree type, tree expr)
3343 fn = instantiate_type (type, fns, tf_none);
3344 if (fn == error_mark_node)
3345 return error_mark_node;
3348 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3349 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3351 /* [temp.arg.nontype]/1
3353 A template-argument for a non-type, non-template template-parameter
3356 -- the address of an object or function with external linkage. */
3357 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3359 error ("%qE is not a valid template argument for type %qT "
3360 "because function %qD has not external linkage",
3361 expr, type, fn_no_ptr);
3368 /* Attempt to convert the non-type template parameter EXPR to the
3369 indicated TYPE. If the conversion is successful, return the
3370 converted value. If the conversion is unsuccessful, return
3371 NULL_TREE if we issued an error message, or error_mark_node if we
3372 did not. We issue error messages for out-and-out bad template
3373 parameters, but not simply because the conversion failed, since we
3374 might be just trying to do argument deduction. Both TYPE and EXPR
3375 must be non-dependent.
3377 The conversion follows the special rules described in
3378 [temp.arg.nontype], and it is much more strict than an implicit
3381 This function is called twice for each template argument (see
3382 lookup_template_class for a more accurate description of this
3383 problem). This means that we need to handle expressions which
3384 are not valid in a C++ source, but can be created from the
3385 first call (for instance, casts to perform conversions). These
3386 hacks can go away after we fix the double coercion problem. */
3389 convert_nontype_argument (tree type, tree expr)
3393 /* Detect immediately string literals as invalid non-type argument.
3394 This special-case is not needed for correctness (we would easily
3395 catch this later), but only to provide better diagnostic for this
3396 common user mistake. As suggested by DR 100, we do not mention
3397 linkage issues in the diagnostic as this is not the point. */
3398 if (TREE_CODE (expr) == STRING_CST)
3400 error ("%qE is not a valid template argument for type %qT "
3401 "because string literals can never be used in this context",
3406 /* If we are in a template, EXPR may be non-dependent, but still
3407 have a syntactic, rather than semantic, form. For example, EXPR
3408 might be a SCOPE_REF, rather than the VAR_DECL to which the
3409 SCOPE_REF refers. Preserving the qualifying scope is necessary
3410 so that access checking can be performed when the template is
3411 instantiated -- but here we need the resolved form so that we can
3412 convert the argument. */
3413 expr = fold_non_dependent_expr (expr);
3414 expr_type = TREE_TYPE (expr);
3416 /* HACK: Due to double coercion, we can get a
3417 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3418 which is the tree that we built on the first call (see
3419 below when coercing to reference to object or to reference to
3420 function). We just strip everything and get to the arg.
3421 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3423 if (TREE_CODE (expr) == NOP_EXPR)
3425 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3427 /* ??? Maybe we could use convert_from_reference here, but we
3428 would need to relax its constraints because the NOP_EXPR
3429 could actually change the type to something more cv-qualified,
3430 and this is not folded by convert_from_reference. */
3431 tree addr = TREE_OPERAND (expr, 0);
3432 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3433 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3434 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3435 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3436 (TREE_TYPE (expr_type),
3437 TREE_TYPE (TREE_TYPE (addr))));
3439 expr = TREE_OPERAND (addr, 0);
3440 expr_type = TREE_TYPE (expr);
3443 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3444 parameter is a pointer to object, through decay and
3445 qualification conversion. Let's strip everything. */
3446 else if (TYPE_PTROBV_P (type))
3449 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3450 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3451 /* Skip the ADDR_EXPR only if it is part of the decay for
3452 an array. Otherwise, it is part of the original argument
3453 in the source code. */
3454 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3455 expr = TREE_OPERAND (expr, 0);
3456 expr_type = TREE_TYPE (expr);
3460 /* [temp.arg.nontype]/5, bullet 1
3462 For a non-type template-parameter of integral or enumeration type,
3463 integral promotions (_conv.prom_) and integral conversions
3464 (_conv.integral_) are applied. */
3465 if (INTEGRAL_TYPE_P (type))
3467 if (!INTEGRAL_TYPE_P (expr_type))
3468 return error_mark_node;
3470 expr = fold_decl_constant_value (expr);
3471 /* Notice that there are constant expressions like '4 % 0' which
3472 do not fold into integer constants. */
3473 if (TREE_CODE (expr) != INTEGER_CST)
3475 error ("%qE is not a valid template argument for type %qT "
3476 "because it is a non-constant expression", expr, type);
3480 /* At this point, an implicit conversion does what we want,
3481 because we already know that the expression is of integral
3483 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3484 if (expr == error_mark_node)
3485 return error_mark_node;
3487 /* Conversion was allowed: fold it to a bare integer constant. */
3490 /* [temp.arg.nontype]/5, bullet 2
3492 For a non-type template-parameter of type pointer to object,
3493 qualification conversions (_conv.qual_) and the array-to-pointer
3494 conversion (_conv.array_) are applied. */
3495 else if (TYPE_PTROBV_P (type))
3497 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3499 A template-argument for a non-type, non-template template-parameter
3500 shall be one of: [...]
3502 -- the name of a non-type template-parameter;
3503 -- the address of an object or function with external linkage, [...]
3504 expressed as "& id-expression" where the & is optional if the name
3505 refers to a function or array, or if the corresponding
3506 template-parameter is a reference.
3508 Here, we do not care about functions, as they are invalid anyway
3509 for a parameter of type pointer-to-object. */
3510 bool constant_address_p =
3511 (TREE_CODE (expr) == ADDR_EXPR
3512 || TREE_CODE (expr_type) == ARRAY_TYPE
3513 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3515 expr = decay_conversion (expr);
3516 if (expr == error_mark_node)
3517 return error_mark_node;
3519 expr = perform_qualification_conversions (type, expr);
3520 if (expr == error_mark_node)
3521 return error_mark_node;
3523 if (!constant_address_p)
3525 error ("%qE is not a valid template argument for type %qT "
3526 "because it is not a constant pointer", expr, type);
3530 /* [temp.arg.nontype]/5, bullet 3
3532 For a non-type template-parameter of type reference to object, no
3533 conversions apply. The type referred to by the reference may be more
3534 cv-qualified than the (otherwise identical) type of the
3535 template-argument. The template-parameter is bound directly to the
3536 template-argument, which must be an lvalue. */
3537 else if (TYPE_REF_OBJ_P (type))
3539 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3541 return error_mark_node;
3543 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3545 error ("%qE is not a valid template argument for type %qT "
3546 "because of conflicts in cv-qualification", expr, type);
3550 if (!real_lvalue_p (expr))
3552 error ("%qE is not a valid template argument for type %qT "
3553 "because it is not a lvalue", expr, type);
3557 /* [temp.arg.nontype]/1
3559 A template-argument for a non-type, non-template template-parameter
3560 shall be one of: [...]
3562 -- the address of an object or function with external linkage. */
3563 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3565 error ("%qE is not a valid template argument for type %qT "
3566 "because object %qD has not external linkage",
3571 expr = build_nop (type, build_address (expr));
3573 /* [temp.arg.nontype]/5, bullet 4
3575 For a non-type template-parameter of type pointer to function, only
3576 the function-to-pointer conversion (_conv.func_) is applied. If the
3577 template-argument represents a set of overloaded functions (or a
3578 pointer to such), the matching function is selected from the set
3580 else if (TYPE_PTRFN_P (type))
3582 /* If the argument is a template-id, we might not have enough
3583 context information to decay the pointer.
3584 ??? Why static5.C requires decay and subst1.C works fine
3586 if (!type_unknown_p (expr_type))
3588 expr = decay_conversion (expr);
3589 if (expr == error_mark_node)
3590 return error_mark_node;
3593 expr = convert_nontype_argument_function (type, expr);
3594 if (!expr || expr == error_mark_node)
3597 /* [temp.arg.nontype]/5, bullet 5
3599 For a non-type template-parameter of type reference to function, no
3600 conversions apply. If the template-argument represents a set of
3601 overloaded functions, the matching function is selected from the set
3603 else if (TYPE_REFFN_P (type))
3605 if (TREE_CODE (expr) == ADDR_EXPR)
3607 error ("%qE is not a valid template argument for type %qT "
3608 "because it is a pointer", expr, type);
3609 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3613 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3614 if (!expr || expr == error_mark_node)
3617 expr = build_nop (type, build_address (expr));
3619 /* [temp.arg.nontype]/5, bullet 6
3621 For a non-type template-parameter of type pointer to member function,
3622 no conversions apply. If the template-argument represents a set of
3623 overloaded member functions, the matching member function is selected
3624 from the set (_over.over_). */
3625 else if (TYPE_PTRMEMFUNC_P (type))
3627 expr = instantiate_type (type, expr, tf_none);
3628 if (expr == error_mark_node)
3629 return error_mark_node;
3631 /* There is no way to disable standard conversions in
3632 resolve_address_of_overloaded_function (called by
3633 instantiate_type). It is possible that the call succeeded by
3634 converting &B::I to &D::I (where B is a base of D), so we need
3635 to reject this conversion here.
3637 Actually, even if there was a way to disable standard conversions,
3638 it would still be better to reject them here so that we can
3639 provide a superior diagnostic. */
3640 if (!same_type_p (TREE_TYPE (expr), type))
3642 /* Make sure we are just one standard conversion off. */
3643 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3644 error ("%qE is not a valid template argument for type %qT "
3645 "because it is of type %qT", expr, type,
3647 inform ("standard conversions are not allowed in this context");
3651 /* [temp.arg.nontype]/5, bullet 7
3653 For a non-type template-parameter of type pointer to data member,
3654 qualification conversions (_conv.qual_) are applied. */
3655 else if (TYPE_PTRMEM_P (type))
3657 expr = perform_qualification_conversions (type, expr);
3658 if (expr == error_mark_node)
3661 /* A template non-type parameter must be one of the above. */
3665 /* Sanity check: did we actually convert the argument to the
3667 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3672 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3673 template template parameters. Both PARM_PARMS and ARG_PARMS are
3674 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3677 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3678 the case, then extra parameters must have default arguments.
3680 Consider the example:
3681 template <class T, class Allocator = allocator> class vector;
3682 template<template <class U> class TT> class C;
3684 C<vector> is a valid instantiation. PARM_PARMS for the above code
3685 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3686 T and Allocator) and OUTER_ARGS contains the argument that is used to
3687 substitute the TT parameter. */
3690 coerce_template_template_parms (tree parm_parms,
3692 tsubst_flags_t complain,
3696 int nparms, nargs, i;
3699 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3700 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3702 nparms = TREE_VEC_LENGTH (parm_parms);
3703 nargs = TREE_VEC_LENGTH (arg_parms);
3705 /* The rule here is opposite of coerce_template_parms. */
3708 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3711 for (i = 0; i < nparms; ++i)
3713 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3714 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3716 if (arg == NULL_TREE || arg == error_mark_node
3717 || parm == NULL_TREE || parm == error_mark_node)
3720 if (TREE_CODE (arg) != TREE_CODE (parm))
3723 switch (TREE_CODE (parm))
3729 /* We encounter instantiations of templates like
3730 template <template <template <class> class> class TT>
3733 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3734 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3736 if (!coerce_template_template_parms
3737 (parmparm, argparm, complain, in_decl, outer_args))
3743 /* The tsubst call is used to handle cases such as
3745 template <int> class C {};
3746 template <class T, template <T> class TT> class D {};
3749 i.e. the parameter list of TT depends on earlier parameters. */
3750 if (!dependent_type_p (TREE_TYPE (arg))
3752 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3764 /* Convert the indicated template ARG as necessary to match the
3765 indicated template PARM. Returns the converted ARG, or
3766 error_mark_node if the conversion was unsuccessful. Error and
3767 warning messages are issued under control of COMPLAIN. This
3768 conversion is for the Ith parameter in the parameter list. ARGS is
3769 the full set of template arguments deduced so far. */
3772 convert_template_argument (tree parm,
3775 tsubst_flags_t complain,
3781 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3783 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3785 if (TREE_CODE (arg) == TREE_LIST
3786 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3788 /* The template argument was the name of some
3789 member function. That's usually
3790 invalid, but static members are OK. In any
3791 case, grab the underlying fields/functions
3792 and issue an error later if required. */
3793 arg = TREE_VALUE (arg);
3794 TREE_TYPE (arg) = unknown_type_node;
3797 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3798 requires_type = (TREE_CODE (parm) == TYPE_DECL
3799 || requires_tmpl_type);
3801 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3802 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3803 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3804 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3807 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3808 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3809 arg = TYPE_STUB_DECL (arg);
3811 is_type = TYPE_P (arg) || is_tmpl_type;
3813 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3814 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3816 pedwarn ("to refer to a type member of a template parameter, "
3817 "use %<typename %E%>", arg);
3819 arg = make_typename_type (TREE_OPERAND (arg, 0),
3820 TREE_OPERAND (arg, 1),
3822 complain & tf_error);
3825 if (is_type != requires_type)
3829 if (complain & tf_error)
3831 error ("type/value mismatch at argument %d in template "
3832 "parameter list for %qD",
3835 error (" expected a constant of type %qT, got %qT",
3837 (is_tmpl_type ? DECL_NAME (arg) : arg));
3838 else if (requires_tmpl_type)
3839 error (" expected a class template, got %qE", arg);
3841 error (" expected a type, got %qE", arg);
3844 return error_mark_node;
3846 if (is_tmpl_type ^ requires_tmpl_type)
3848 if (in_decl && (complain & tf_error))
3850 error ("type/value mismatch at argument %d in template "
3851 "parameter list for %qD",
3854 error (" expected a type, got %qT", DECL_NAME (arg));
3856 error (" expected a class template, got %qT", arg);
3858 return error_mark_node;
3863 if (requires_tmpl_type)
3865 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3866 /* The number of argument required is not known yet.
3867 Just accept it for now. */
3868 val = TREE_TYPE (arg);
3871 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3872 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3874 if (coerce_template_template_parms (parmparm, argparm,
3880 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3882 if (val != error_mark_node
3883 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3884 val = TREE_TYPE (val);
3888 if (in_decl && (complain & tf_error))
3890 error ("type/value mismatch at argument %d in "
3891 "template parameter list for %qD",
3893 error (" expected a template of type %qD, got %qD",
3897 val = error_mark_node;
3906 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3908 if (invalid_nontype_parm_type_p (t, complain))
3909 return error_mark_node;
3911 if (!uses_template_parms (arg) && !uses_template_parms (t))
3912 /* We used to call digest_init here. However, digest_init
3913 will report errors, which we don't want when complain
3914 is zero. More importantly, digest_init will try too
3915 hard to convert things: for example, `0' should not be
3916 converted to pointer type at this point according to
3917 the standard. Accepting this is not merely an
3918 extension, since deciding whether or not these
3919 conversions can occur is part of determining which
3920 function template to call, or whether a given explicit
3921 argument specification is valid. */
3922 val = convert_nontype_argument (t, arg);
3926 if (val == NULL_TREE)
3927 val = error_mark_node;
3928 else if (val == error_mark_node && (complain & tf_error))
3929 error ("could not convert template argument %qE to %qT", arg, t);
3935 /* Convert all template arguments to their appropriate types, and
3936 return a vector containing the innermost resulting template
3937 arguments. If any error occurs, return error_mark_node. Error and
3938 warning messages are issued under control of COMPLAIN.
3940 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3941 provided in ARGLIST, or else trailing parameters must have default
3942 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3943 deduction for any unspecified trailing arguments. */
3946 coerce_template_parms (tree parms,
3949 tsubst_flags_t complain,
3950 int require_all_arguments)
3952 int nparms, nargs, i, lost = 0;
3955 tree new_inner_args;
3957 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3958 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3959 nparms = TREE_VEC_LENGTH (parms);
3963 && require_all_arguments
3964 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3966 if (complain & tf_error)
3968 error ("wrong number of template arguments (%d, should be %d)",
3972 error ("provided for %q+D", in_decl);
3975 return error_mark_node;
3978 new_inner_args = make_tree_vec (nparms);
3979 new_args = add_outermost_template_args (args, new_inner_args);
3980 for (i = 0; i < nparms; i++)
3985 /* Get the Ith template parameter. */
3986 parm = TREE_VEC_ELT (parms, i);
3988 /* Calculate the Ith argument. */
3990 arg = TREE_VEC_ELT (inner_args, i);
3991 else if (require_all_arguments)
3992 /* There must be a default arg in this case. */
3993 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
3999 if (arg == error_mark_node)
4001 if (complain & tf_error)
4002 error ("template argument %d is invalid", i + 1);
4005 arg = convert_template_argument (TREE_VALUE (parm),
4006 arg, new_args, complain, i,
4009 if (arg == error_mark_node)
4011 TREE_VEC_ELT (new_inner_args, i) = arg;
4015 return error_mark_node;
4017 return new_inner_args;
4020 /* Returns 1 if template args OT and NT are equivalent. */
4023 template_args_equal (tree ot, tree nt)
4028 if (TREE_CODE (nt) == TREE_VEC)
4029 /* For member templates */
4030 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4031 else if (TYPE_P (nt))
4032 return TYPE_P (ot) && same_type_p (ot, nt);
4033 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4036 return cp_tree_equal (ot, nt);
4039 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4040 of template arguments. Returns 0 otherwise. */
4043 comp_template_args (tree oldargs, tree newargs)
4047 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4050 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4052 tree nt = TREE_VEC_ELT (newargs, i);
4053 tree ot = TREE_VEC_ELT (oldargs, i);
4055 if (! template_args_equal (ot, nt))
4061 /* Given class template name and parameter list, produce a user-friendly name
4062 for the instantiation. */
4065 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4067 static struct obstack scratch_obstack;
4068 static char *scratch_firstobj;
4071 if (!scratch_firstobj)
4072 gcc_obstack_init (&scratch_obstack);
4074 obstack_free (&scratch_obstack, scratch_firstobj);
4075 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4077 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4078 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4082 nparms = TREE_VEC_LENGTH (parms);
4083 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4084 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4085 for (i = 0; i < nparms; i++)
4087 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4088 tree arg = TREE_VEC_ELT (arglist, i);
4093 if (TREE_CODE (parm) == TYPE_DECL)
4095 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4098 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4100 if (TREE_CODE (arg) == TEMPLATE_DECL)
4102 /* Already substituted with real template. Just output
4103 the template name here */
4104 tree context = DECL_CONTEXT (arg);
4107 /* The template may be defined in a namespace, or
4108 may be a member template. */
4109 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4110 || CLASS_TYPE_P (context));
4111 cat (decl_as_string (DECL_CONTEXT (arg),
4112 TFF_PLAIN_IDENTIFIER));
4115 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4118 /* Output the parameter declaration. */
4119 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4123 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4125 /* No need to check arglist against parmlist here; we did that
4126 in coerce_template_parms, called from lookup_template_class. */
4127 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4130 char *bufp = obstack_next_free (&scratch_obstack);
4132 while (bufp[offset - 1] == ' ')
4134 obstack_blank_fast (&scratch_obstack, offset);
4136 /* B<C<char> >, not B<C<char>> */
4137 if (bufp[offset - 1] == '>')
4142 return (char *) obstack_base (&scratch_obstack);
4146 classtype_mangled_name (tree t)
4148 if (CLASSTYPE_TEMPLATE_INFO (t)
4149 /* Specializations have already had their names set up in
4150 lookup_template_class. */
4151 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4153 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4155 /* For non-primary templates, the template parameters are
4156 implicit from their surrounding context. */
4157 if (PRIMARY_TEMPLATE_P (tmpl))
4159 tree name = DECL_NAME (tmpl);
4160 char *mangled_name = mangle_class_name_for_template
4161 (IDENTIFIER_POINTER (name),
4162 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4163 CLASSTYPE_TI_ARGS (t));
4164 tree id = get_identifier (mangled_name);
4165 IDENTIFIER_TEMPLATE (id) = name;
4170 return TYPE_IDENTIFIER (t);
4174 add_pending_template (tree d)
4176 tree ti = (TYPE_P (d)
4177 ? CLASSTYPE_TEMPLATE_INFO (d)
4178 : DECL_TEMPLATE_INFO (d));
4182 if (TI_PENDING_TEMPLATE_FLAG (ti))
4185 /* We are called both from instantiate_decl, where we've already had a
4186 tinst_level pushed, and instantiate_template, where we haven't.
4188 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4191 push_tinst_level (d);
4193 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4194 if (last_pending_template)
4195 TREE_CHAIN (last_pending_template) = pt;
4197 pending_templates = pt;
4199 last_pending_template = pt;
4201 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4208 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4209 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4210 documentation for TEMPLATE_ID_EXPR. */
4213 lookup_template_function (tree fns, tree arglist)
4217 if (fns == error_mark_node || arglist == error_mark_node)
4218 return error_mark_node;
4220 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4221 gcc_assert (fns && (is_overloaded_fn (fns)
4222 || TREE_CODE (fns) == IDENTIFIER_NODE));
4224 if (BASELINK_P (fns))
4226 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4228 BASELINK_FUNCTIONS (fns),
4233 type = TREE_TYPE (fns);
4234 if (TREE_CODE (fns) == OVERLOAD || !type)
4235 type = unknown_type_node;
4237 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4240 /* Within the scope of a template class S<T>, the name S gets bound
4241 (in build_self_reference) to a TYPE_DECL for the class, not a
4242 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4243 or one of its enclosing classes, and that type is a template,
4244 return the associated TEMPLATE_DECL. Otherwise, the original
4245 DECL is returned. */
4248 maybe_get_template_decl_from_type_decl (tree decl)
4250 return (decl != NULL_TREE
4251 && TREE_CODE (decl) == TYPE_DECL
4252 && DECL_ARTIFICIAL (decl)
4253 && CLASS_TYPE_P (TREE_TYPE (decl))
4254 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4255 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4258 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4259 parameters, find the desired type.
4261 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4263 IN_DECL, if non-NULL, is the template declaration we are trying to
4266 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4267 the class we are looking up.
4269 Issue error and warning messages under control of COMPLAIN.
4271 If the template class is really a local class in a template
4272 function, then the FUNCTION_CONTEXT is the function in which it is
4275 ??? Note that this function is currently called *twice* for each
4276 template-id: the first time from the parser, while creating the
4277 incomplete type (finish_template_type), and the second type during the
4278 real instantiation (instantiate_template_class). This is surely something
4279 that we want to avoid. It also causes some problems with argument
4280 coercion (see convert_nontype_argument for more information on this). */
4283 lookup_template_class (tree d1,
4288 tsubst_flags_t complain)
4290 tree template = NULL_TREE, parmlist;
4293 timevar_push (TV_NAME_LOOKUP);
4295 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4297 tree value = innermost_non_namespace_value (d1);
4298 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4303 push_decl_namespace (context);
4304 template = lookup_name (d1, /*prefer_type=*/0);
4305 template = maybe_get_template_decl_from_type_decl (template);
4307 pop_decl_namespace ();
4310 context = DECL_CONTEXT (template);
4312 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4314 tree type = TREE_TYPE (d1);
4316 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4317 an implicit typename for the second A. Deal with it. */
4318 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4319 type = TREE_TYPE (type);
4321 if (CLASSTYPE_TEMPLATE_INFO (type))
4323 template = CLASSTYPE_TI_TEMPLATE (type);
4324 d1 = DECL_NAME (template);
4327 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4328 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4330 template = TYPE_TI_TEMPLATE (d1);
4331 d1 = DECL_NAME (template);
4333 else if (TREE_CODE (d1) == TEMPLATE_DECL
4334 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4337 d1 = DECL_NAME (template);
4338 context = DECL_CONTEXT (template);
4341 /* Issue an error message if we didn't find a template. */
4344 if (complain & tf_error)
4345 error ("%qT is not a template", d1);
4346 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4349 if (TREE_CODE (template) != TEMPLATE_DECL
4350 /* Make sure it's a user visible template, if it was named by
4352 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4353 && !PRIMARY_TEMPLATE_P (template)))
4355 if (complain & tf_error)
4357 error ("non-template type %qT used as a template", d1);
4359 error ("for template declaration %q+D", in_decl);
4361 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4364 complain &= ~tf_user;
4366 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4368 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4369 template arguments */
4374 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4376 /* Consider an example where a template template parameter declared as
4378 template <class T, class U = std::allocator<T> > class TT
4380 The template parameter level of T and U are one level larger than
4381 of TT. To proper process the default argument of U, say when an
4382 instantiation `TT<int>' is seen, we need to build the full
4383 arguments containing {int} as the innermost level. Outer levels,
4384 available when not appearing as default template argument, can be
4385 obtained from `current_template_args ()'.
4387 Suppose that TT is later substituted with std::vector. The above
4388 instantiation is `TT<int, std::allocator<T> >' with TT at
4389 level 1, and T at level 2, while the template arguments at level 1
4390 becomes {std::vector} and the inner level 2 is {int}. */
4392 if (current_template_parms)
4393 arglist = add_to_template_args (current_template_args (), arglist);
4395 arglist2 = coerce_template_parms (parmlist, arglist, template,
4396 complain, /*require_all_args=*/1);
4397 if (arglist2 == error_mark_node
4398 || (!uses_template_parms (arglist2)
4399 && check_instantiated_args (template, arglist2, complain)))
4400 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4402 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4403 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4407 tree template_type = TREE_TYPE (template);
4410 tree found = NULL_TREE;
4413 int is_partial_instantiation;
4415 gen_tmpl = most_general_template (template);
4416 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4417 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4418 arg_depth = TMPL_ARGS_DEPTH (arglist);
4420 if (arg_depth == 1 && parm_depth > 1)
4422 /* We've been given an incomplete set of template arguments.
4425 template <class T> struct S1 {
4426 template <class U> struct S2 {};
4427 template <class U> struct S2<U*> {};
4430 we will be called with an ARGLIST of `U*', but the
4431 TEMPLATE will be `template <class T> template
4432 <class U> struct S1<T>::S2'. We must fill in the missing
4435 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4437 arg_depth = TMPL_ARGS_DEPTH (arglist);
4440 /* Now we should have enough arguments. */
4441 gcc_assert (parm_depth == arg_depth);
4443 /* From here on, we're only interested in the most general
4445 template = gen_tmpl;
4447 /* Calculate the BOUND_ARGS. These will be the args that are
4448 actually tsubst'd into the definition to create the
4452 /* We have multiple levels of arguments to coerce, at once. */
4454 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4456 tree bound_args = make_tree_vec (parm_depth);
4458 for (i = saved_depth,
4459 t = DECL_TEMPLATE_PARMS (template);
4460 i > 0 && t != NULL_TREE;
4461 --i, t = TREE_CHAIN (t))
4463 tree a = coerce_template_parms (TREE_VALUE (t),
4465 complain, /*require_all_args=*/1);
4467 /* Don't process further if one of the levels fails. */
4468 if (a == error_mark_node)
4470 /* Restore the ARGLIST to its full size. */
4471 TREE_VEC_LENGTH (arglist) = saved_depth;
4472 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4475 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4477 /* We temporarily reduce the length of the ARGLIST so
4478 that coerce_template_parms will see only the arguments
4479 corresponding to the template parameters it is
4481 TREE_VEC_LENGTH (arglist)--;
4484 /* Restore the ARGLIST to its full size. */
4485 TREE_VEC_LENGTH (arglist) = saved_depth;
4487 arglist = bound_args;
4491 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4492 INNERMOST_TEMPLATE_ARGS (arglist),
4494 complain, /*require_all_args=*/1);
4496 if (arglist == error_mark_node)
4497 /* We were unable to bind the arguments. */
4498 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4500 /* In the scope of a template class, explicit references to the
4501 template class refer to the type of the template, not any
4502 instantiation of it. For example, in:
4504 template <class T> class C { void f(C<T>); }
4506 the `C<T>' is just the same as `C'. Outside of the
4507 class, however, such a reference is an instantiation. */
4508 if (comp_template_args (TYPE_TI_ARGS (template_type),
4511 found = template_type;
4513 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4517 for (ctx = current_class_type;
4518 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4520 ? TYPE_CONTEXT (ctx)
4521 : DECL_CONTEXT (ctx)))
4522 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4525 /* We're not in the scope of the class, so the
4526 TEMPLATE_TYPE is not the type we want after all. */
4532 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4534 /* If we already have this specialization, return it. */
4535 found = retrieve_specialization (template, arglist,
4536 /*class_specializations_p=*/false);
4538 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4540 /* This type is a "partial instantiation" if any of the template
4541 arguments still involve template parameters. Note that we set
4542 IS_PARTIAL_INSTANTIATION for partial specializations as
4544 is_partial_instantiation = uses_template_parms (arglist);
4546 /* If the deduced arguments are invalid, then the binding
4548 if (!is_partial_instantiation
4549 && check_instantiated_args (template,
4550 INNERMOST_TEMPLATE_ARGS (arglist),
4552 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4554 if (!is_partial_instantiation
4555 && !PRIMARY_TEMPLATE_P (template)
4556 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4558 found = xref_tag_from_type (TREE_TYPE (template),
4559 DECL_NAME (template),
4560 /*tag_scope=*/ts_global);
4561 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4564 context = tsubst (DECL_CONTEXT (template), arglist,
4567 context = global_namespace;
4569 /* Create the type. */
4570 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4572 if (!is_partial_instantiation)
4574 set_current_access_from_decl (TYPE_NAME (template_type));
4575 t = start_enum (TYPE_IDENTIFIER (template_type));
4578 /* We don't want to call start_enum for this type, since
4579 the values for the enumeration constants may involve
4580 template parameters. And, no one should be interested
4581 in the enumeration constants for such a type. */
4582 t = make_node (ENUMERAL_TYPE);
4586 t = make_aggr_type (TREE_CODE (template_type));
4587 CLASSTYPE_DECLARED_CLASS (t)
4588 = CLASSTYPE_DECLARED_CLASS (template_type);
4589 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4590 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4592 /* A local class. Make sure the decl gets registered properly. */
4593 if (context == current_function_decl)
4594 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
4597 /* If we called start_enum or pushtag above, this information
4598 will already be set up. */
4601 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4603 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4604 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4605 TYPE_STUB_DECL (t) = type_decl;
4606 DECL_SOURCE_LOCATION (type_decl)
4607 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4610 type_decl = TYPE_NAME (t);
4612 TREE_PRIVATE (type_decl)
4613 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4614 TREE_PROTECTED (type_decl)
4615 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4616 DECL_IN_SYSTEM_HEADER (type_decl)
4617 = DECL_IN_SYSTEM_HEADER (template);
4618 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
4620 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
4621 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
4624 /* Set up the template information. We have to figure out which
4625 template is the immediate parent if this is a full
4627 if (parm_depth == 1 || is_partial_instantiation
4628 || !PRIMARY_TEMPLATE_P (template))
4629 /* This case is easy; there are no member templates involved. */
4633 /* This is a full instantiation of a member template. Look
4634 for a partial instantiation of which this is an instance. */
4636 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4637 found; found = TREE_CHAIN (found))
4640 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4642 /* We only want partial instantiations, here, not
4643 specializations or full instantiations. */
4644 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4645 || !uses_template_parms (TREE_VALUE (found)))
4648 /* Temporarily reduce by one the number of levels in the
4649 ARGLIST and in FOUND so as to avoid comparing the
4650 last set of arguments. */
4651 TREE_VEC_LENGTH (arglist)--;
4652 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4654 /* See if the arguments match. If they do, then TMPL is
4655 the partial instantiation we want. */
4656 success = comp_template_args (TREE_PURPOSE (found), arglist);
4658 /* Restore the argument vectors to their full size. */
4659 TREE_VEC_LENGTH (arglist)++;
4660 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4671 /* There was no partial instantiation. This happens
4672 where C<T> is a member template of A<T> and it's used
4675 template <typename T> struct B { A<T>::C<int> m; };
4678 Create the partial instantiation.
4680 TREE_VEC_LENGTH (arglist)--;
4681 found = tsubst (template, arglist, complain, NULL_TREE);
4682 TREE_VEC_LENGTH (arglist)++;
4686 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4687 DECL_TEMPLATE_INSTANTIATIONS (template)
4688 = tree_cons (arglist, t,
4689 DECL_TEMPLATE_INSTANTIATIONS (template));
4691 if (TREE_CODE (t) == ENUMERAL_TYPE
4692 && !is_partial_instantiation)
4693 /* Now that the type has been registered on the instantiations
4694 list, we set up the enumerators. Because the enumeration
4695 constants may involve the enumeration type itself, we make
4696 sure to register the type first, and then create the
4697 constants. That way, doing tsubst_expr for the enumeration
4698 constants won't result in recursive calls here; we'll find
4699 the instantiation and exit above. */
4700 tsubst_enum (template_type, t, arglist);
4702 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4704 if (TREE_CODE (t) != ENUMERAL_TYPE)
4705 DECL_NAME (type_decl) = classtype_mangled_name (t);
4706 if (is_partial_instantiation)
4707 /* If the type makes use of template parameters, the
4708 code that generates debugging information will crash. */
4709 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4711 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4713 timevar_pop (TV_NAME_LOOKUP);
4720 struct pointer_set_t *visited;
4723 /* Called from for_each_template_parm via walk_tree. */
4726 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4729 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4730 tree_fn_t fn = pfd->fn;
4731 void *data = pfd->data;
4734 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4735 return error_mark_node;
4737 switch (TREE_CODE (t))
4740 if (TYPE_PTRMEMFUNC_P (t))
4746 if (!TYPE_TEMPLATE_INFO (t))
4748 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4749 fn, data, pfd->visited))
4750 return error_mark_node;
4754 /* Since we're not going to walk subtrees, we have to do this
4756 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4758 return error_mark_node;
4762 /* Check the return type. */
4763 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4764 return error_mark_node;
4766 /* Check the parameter types. Since default arguments are not
4767 instantiated until they are needed, the TYPE_ARG_TYPES may
4768 contain expressions that involve template parameters. But,
4769 no-one should be looking at them yet. And, once they're
4770 instantiated, they don't contain template parameters, so
4771 there's no point in looking at them then, either. */
4775 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4776 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4778 return error_mark_node;
4780 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4781 want walk_tree walking into them itself. */
4787 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4789 return error_mark_node;
4794 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4795 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4797 return error_mark_node;
4802 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4803 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4805 return error_mark_node;
4806 if (DECL_CONTEXT (t)
4807 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4809 return error_mark_node;
4812 case BOUND_TEMPLATE_TEMPLATE_PARM:
4813 /* Record template parameters such as `T' inside `TT<T>'. */
4814 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4815 return error_mark_node;
4818 case TEMPLATE_TEMPLATE_PARM:
4819 case TEMPLATE_TYPE_PARM:
4820 case TEMPLATE_PARM_INDEX:
4821 if (fn && (*fn)(t, data))
4822 return error_mark_node;
4824 return error_mark_node;
4828 /* A template template parameter is encountered. */
4829 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4830 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4831 return error_mark_node;
4833 /* Already substituted template template parameter */
4839 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4840 data, pfd->visited))
4841 return error_mark_node;
4845 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4846 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4847 (TREE_TYPE (t)), fn, data,
4849 return error_mark_node;
4854 /* If there's no type, then this thing must be some expression
4855 involving template parameters. */
4856 if (!fn && !TREE_TYPE (t))
4857 return error_mark_node;
4862 case REINTERPRET_CAST_EXPR:
4863 case CONST_CAST_EXPR:
4864 case STATIC_CAST_EXPR:
4865 case DYNAMIC_CAST_EXPR:
4869 case PSEUDO_DTOR_EXPR:
4871 return error_mark_node;
4875 /* If we do not handle this case specially, we end up walking
4876 the BINFO hierarchy, which is circular, and therefore
4877 confuses walk_tree. */
4879 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4881 return error_mark_node;
4888 /* We didn't find any template parameters we liked. */
4892 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4893 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4894 call FN with the parameter and the DATA.
4895 If FN returns nonzero, the iteration is terminated, and
4896 for_each_template_parm returns 1. Otherwise, the iteration
4897 continues. If FN never returns a nonzero value, the value
4898 returned by for_each_template_parm is 0. If FN is NULL, it is
4899 considered to be the function which always returns 1. */
4902 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4903 struct pointer_set_t *visited)
4905 struct pair_fn_data pfd;
4912 /* Walk the tree. (Conceptually, we would like to walk without
4913 duplicates, but for_each_template_parm_r recursively calls
4914 for_each_template_parm, so we would need to reorganize a fair
4915 bit to use walk_tree_without_duplicates, so we keep our own
4918 pfd.visited = visited;
4920 pfd.visited = pointer_set_create ();
4921 result = walk_tree (&t,
4922 for_each_template_parm_r,
4924 pfd.visited) != NULL_TREE;
4929 pointer_set_destroy (pfd.visited);
4936 /* Returns true if T depends on any template parameter. */
4939 uses_template_parms (tree t)
4942 int saved_processing_template_decl;
4944 saved_processing_template_decl = processing_template_decl;
4945 if (!saved_processing_template_decl)
4946 processing_template_decl = 1;
4948 dependent_p = dependent_type_p (t);
4949 else if (TREE_CODE (t) == TREE_VEC)
4950 dependent_p = any_dependent_template_arguments_p (t);
4951 else if (TREE_CODE (t) == TREE_LIST)
4952 dependent_p = (uses_template_parms (TREE_VALUE (t))
4953 || uses_template_parms (TREE_CHAIN (t)));
4956 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4957 || TREE_CODE (t) == OVERLOAD
4958 || TREE_CODE (t) == BASELINK
4959 || TREE_CODE (t) == IDENTIFIER_NODE
4960 || CONSTANT_CLASS_P (t))
4961 dependent_p = (type_dependent_expression_p (t)
4962 || value_dependent_expression_p (t));
4965 gcc_assert (t == error_mark_node);
4966 dependent_p = false;
4969 processing_template_decl = saved_processing_template_decl;
4974 /* Returns true if T depends on any template parameter with level LEVEL. */
4977 uses_template_parms_level (tree t, int level)
4979 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
4982 static int tinst_depth;
4983 extern int max_tinst_depth;
4984 #ifdef GATHER_STATISTICS
4987 static int tinst_level_tick;
4988 static int last_template_error_tick;
4990 /* We're starting to instantiate D; record the template instantiation context
4991 for diagnostics and to restore it later. */
4994 push_tinst_level (tree d)
4998 if (tinst_depth >= max_tinst_depth)
5000 /* If the instantiation in question still has unbound template parms,
5001 we don't really care if we can't instantiate it, so just return.
5002 This happens with base instantiation for implicit `typename'. */
5003 if (uses_template_parms (d))
5006 last_template_error_tick = tinst_level_tick;
5007 error ("template instantiation depth exceeds maximum of %d (use "
5008 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5009 max_tinst_depth, d);
5011 print_instantiation_context ();
5016 new = make_node (TINST_LEVEL);
5017 TINST_DECL (new) = d;
5018 TINST_LOCATION (new) = input_location;
5019 TINST_IN_SYSTEM_HEADER_P (new) = in_system_header;
5020 TREE_CHAIN (new) = current_tinst_level;
5021 current_tinst_level = new;
5024 #ifdef GATHER_STATISTICS
5025 if (tinst_depth > depth_reached)
5026 depth_reached = tinst_depth;
5033 /* We're done instantiating this template; return to the instantiation
5037 pop_tinst_level (void)
5039 tree old = current_tinst_level;
5041 /* Restore the filename and line number stashed away when we started
5042 this instantiation. */
5043 input_location = TINST_LOCATION (old);
5044 in_system_header = TINST_IN_SYSTEM_HEADER_P (old);
5045 current_tinst_level = TREE_CHAIN (old);
5050 /* We're instantiating a deferred template; restore the template
5051 instantiation context in which the instantiation was requested, which
5052 is one step out from LEVEL. */
5055 reopen_tinst_level (tree level)
5060 for (t = level; t; t = TREE_CHAIN (t))
5063 current_tinst_level = level;
5067 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5068 vector of template arguments, as for tsubst.
5070 Returns an appropriate tsubst'd friend declaration. */
5073 tsubst_friend_function (tree decl, tree args)
5077 if (TREE_CODE (decl) == FUNCTION_DECL
5078 && DECL_TEMPLATE_INSTANTIATION (decl)
5079 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5080 /* This was a friend declared with an explicit template
5081 argument list, e.g.:
5085 to indicate that f was a template instantiation, not a new
5086 function declaration. Now, we have to figure out what
5087 instantiation of what template. */
5089 tree template_id, arglist, fns;
5092 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5094 /* Friend functions are looked up in the containing namespace scope.
5095 We must enter that scope, to avoid finding member functions of the
5096 current cless with same name. */
5097 push_nested_namespace (ns);
5098 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5099 tf_error | tf_warning, NULL_TREE);
5100 pop_nested_namespace (ns);
5101 arglist = tsubst (DECL_TI_ARGS (decl), args,
5102 tf_error | tf_warning, NULL_TREE);
5103 template_id = lookup_template_function (fns, arglist);
5105 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5106 tmpl = determine_specialization (template_id, new_friend,
5108 /*need_member_template=*/0,
5109 TREE_VEC_LENGTH (args));
5110 return instantiate_template (tmpl, new_args, tf_error);
5113 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5115 /* The NEW_FRIEND will look like an instantiation, to the
5116 compiler, but is not an instantiation from the point of view of
5117 the language. For example, we might have had:
5119 template <class T> struct S {
5120 template <class U> friend void f(T, U);
5123 Then, in S<int>, template <class U> void f(int, U) is not an
5124 instantiation of anything. */
5125 if (new_friend == error_mark_node)
5126 return error_mark_node;
5128 DECL_USE_TEMPLATE (new_friend) = 0;
5129 if (TREE_CODE (decl) == TEMPLATE_DECL)
5131 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5132 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5133 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5136 /* The mangled name for the NEW_FRIEND is incorrect. The function
5137 is not a template instantiation and should not be mangled like
5138 one. Therefore, we forget the mangling here; we'll recompute it
5139 later if we need it. */
5140 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5142 SET_DECL_RTL (new_friend, NULL_RTX);
5143 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5146 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5149 tree new_friend_template_info;
5150 tree new_friend_result_template_info;
5152 int new_friend_is_defn;
5154 /* We must save some information from NEW_FRIEND before calling
5155 duplicate decls since that function will free NEW_FRIEND if
5157 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5158 new_friend_is_defn =
5159 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5160 (template_for_substitution (new_friend)))
5162 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5164 /* This declaration is a `primary' template. */
5165 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5167 new_friend_result_template_info
5168 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5171 new_friend_result_template_info = NULL_TREE;
5173 /* Inside pushdecl_namespace_level, we will push into the
5174 current namespace. However, the friend function should go
5175 into the namespace of the template. */
5176 ns = decl_namespace_context (new_friend);
5177 push_nested_namespace (ns);
5178 old_decl = pushdecl_namespace_level (new_friend);
5179 pop_nested_namespace (ns);
5181 if (old_decl != new_friend)
5183 /* This new friend declaration matched an existing
5184 declaration. For example, given:
5186 template <class T> void f(T);
5187 template <class U> class C {
5188 template <class T> friend void f(T) {}
5191 the friend declaration actually provides the definition
5192 of `f', once C has been instantiated for some type. So,
5193 old_decl will be the out-of-class template declaration,
5194 while new_friend is the in-class definition.
5196 But, if `f' was called before this point, the
5197 instantiation of `f' will have DECL_TI_ARGS corresponding
5198 to `T' but not to `U', references to which might appear
5199 in the definition of `f'. Previously, the most general
5200 template for an instantiation of `f' was the out-of-class
5201 version; now it is the in-class version. Therefore, we
5202 run through all specialization of `f', adding to their
5203 DECL_TI_ARGS appropriately. In particular, they need a
5204 new set of outer arguments, corresponding to the
5205 arguments for this class instantiation.
5207 The same situation can arise with something like this:
5210 template <class T> class C {
5214 when `C<int>' is instantiated. Now, `f(int)' is defined
5217 if (!new_friend_is_defn)
5218 /* On the other hand, if the in-class declaration does
5219 *not* provide a definition, then we don't want to alter
5220 existing definitions. We can just leave everything
5225 /* Overwrite whatever template info was there before, if
5226 any, with the new template information pertaining to
5228 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5230 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5231 reregister_specialization (new_friend,
5232 most_general_template (old_decl),
5237 tree new_friend_args;
5239 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5240 = new_friend_result_template_info;
5242 new_friend_args = TI_ARGS (new_friend_template_info);
5243 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5247 tree spec = TREE_VALUE (t);
5250 = add_outermost_template_args (new_friend_args,
5251 DECL_TI_ARGS (spec));
5254 /* Now, since specializations are always supposed to
5255 hang off of the most general template, we must move
5257 t = most_general_template (old_decl);
5260 DECL_TEMPLATE_SPECIALIZATIONS (t)
5261 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5262 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5263 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5268 /* The information from NEW_FRIEND has been merged into OLD_DECL
5269 by duplicate_decls. */
5270 new_friend = old_decl;
5275 tree context = DECL_CONTEXT (new_friend);
5279 template <class T> class C {
5280 template <class U> friend void C1<U>::f (); // case 1
5281 friend void C2<T>::f (); // case 2
5283 we only need to make sure CONTEXT is a complete type for
5284 case 2. To distinguish between the two cases, we note that
5285 CONTEXT of case 1 remains dependent type after tsubst while
5286 this isn't true for case 2. */
5287 ++processing_template_decl;
5288 dependent_p = dependent_type_p (context);
5289 --processing_template_decl;
5292 && !complete_type_or_else (context, NULL_TREE))
5293 return error_mark_node;
5295 if (COMPLETE_TYPE_P (context))
5297 /* Check to see that the declaration is really present, and,
5298 possibly obtain an improved declaration. */
5299 tree fn = check_classfn (context,
5300 new_friend, NULL_TREE);
5310 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5311 template arguments, as for tsubst.
5313 Returns an appropriate tsubst'd friend type or error_mark_node on
5317 tsubst_friend_class (tree friend_tmpl, tree args)
5323 context = DECL_CONTEXT (friend_tmpl);
5327 if (TREE_CODE (context) == NAMESPACE_DECL)
5328 push_nested_namespace (context);
5330 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5333 /* First, we look for a class template. */
5334 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5336 /* But, if we don't find one, it might be because we're in a
5337 situation like this:
5345 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5346 for `S<int>', not the TEMPLATE_DECL. */
5347 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5349 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5350 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5353 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5355 /* The friend template has already been declared. Just
5356 check to see that the declarations match, and install any new
5357 default parameters. We must tsubst the default parameters,
5358 of course. We only need the innermost template parameters
5359 because that is all that redeclare_class_template will look
5361 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5362 > TMPL_ARGS_DEPTH (args))
5365 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5366 args, tf_error | tf_warning);
5367 redeclare_class_template (TREE_TYPE (tmpl), parms);
5370 friend_type = TREE_TYPE (tmpl);
5374 /* The friend template has not already been declared. In this
5375 case, the instantiation of the template class will cause the
5376 injection of this template into the global scope. */
5377 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5379 /* The new TMPL is not an instantiation of anything, so we
5380 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5381 the new type because that is supposed to be the corresponding
5382 template decl, i.e., TMPL. */
5383 DECL_USE_TEMPLATE (tmpl) = 0;
5384 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5385 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5386 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5387 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5389 /* Inject this template into the global scope. */
5390 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5395 if (TREE_CODE (context) == NAMESPACE_DECL)
5396 pop_nested_namespace (context);
5398 pop_nested_class ();
5404 /* Returns zero if TYPE cannot be completed later due to circularity.
5405 Otherwise returns one. */
5408 can_complete_type_without_circularity (tree type)
5410 if (type == NULL_TREE || type == error_mark_node)
5412 else if (COMPLETE_TYPE_P (type))
5414 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5415 return can_complete_type_without_circularity (TREE_TYPE (type));
5416 else if (CLASS_TYPE_P (type)
5417 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5424 instantiate_class_template (tree type)
5426 tree template, args, pattern, t, member;
5431 if (type == error_mark_node)
5432 return error_mark_node;
5434 if (TYPE_BEING_DEFINED (type)
5435 || COMPLETE_TYPE_P (type)
5436 || dependent_type_p (type))
5439 /* Figure out which template is being instantiated. */
5440 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5441 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5443 /* Figure out which arguments are being used to do the
5445 args = CLASSTYPE_TI_ARGS (type);
5447 /* Determine what specialization of the original template to
5449 t = most_specialized_class (template, args);
5450 if (t == error_mark_node)
5452 const char *str = "candidates are:";
5453 error ("ambiguous class template instantiation for %q#T", type);
5454 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5457 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5459 error ("%s %+#T", str, TREE_TYPE (t));
5463 TYPE_BEING_DEFINED (type) = 1;
5464 return error_mark_node;
5468 pattern = TREE_TYPE (t);
5470 pattern = TREE_TYPE (template);
5472 /* If the template we're instantiating is incomplete, then clearly
5473 there's nothing we can do. */
5474 if (!COMPLETE_TYPE_P (pattern))
5477 /* If we've recursively instantiated too many templates, stop. */
5478 if (! push_tinst_level (type))
5481 /* Now we're really doing the instantiation. Mark the type as in
5482 the process of being defined. */
5483 TYPE_BEING_DEFINED (type) = 1;
5485 /* We may be in the middle of deferred access check. Disable
5487 push_deferring_access_checks (dk_no_deferred);
5489 push_to_top_level ();
5493 /* This TYPE is actually an instantiation of a partial
5494 specialization. We replace the innermost set of ARGS with
5495 the arguments appropriate for substitution. For example,
5498 template <class T> struct S {};
5499 template <class T> struct S<T*> {};
5501 and supposing that we are instantiating S<int*>, ARGS will
5502 present be {int*} but we need {int}. */
5504 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5507 /* If there were multiple levels in ARGS, replacing the
5508 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5509 want, so we make a copy first. */
5510 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5512 args = copy_node (args);
5513 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5519 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5521 /* Set the input location to the template definition. This is needed
5522 if tsubsting causes an error. */
5523 typedecl = TYPE_MAIN_DECL (type);
5524 input_location = DECL_SOURCE_LOCATION (typedecl);
5525 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
5527 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5528 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5529 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5530 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5531 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5532 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5533 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5534 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5535 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5536 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5537 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5538 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5539 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5540 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5541 if (ANON_AGGR_TYPE_P (pattern))
5542 SET_ANON_AGGR_TYPE_P (type);
5543 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
5545 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
5546 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
5549 pbinfo = TYPE_BINFO (pattern);
5551 /* We should never instantiate a nested class before its enclosing
5552 class; we need to look up the nested class by name before we can
5553 instantiate it, and that lookup should instantiate the enclosing
5555 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5556 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5557 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5559 base_list = NULL_TREE;
5560 if (BINFO_N_BASE_BINFOS (pbinfo))
5563 tree context = TYPE_CONTEXT (type);
5567 /* We must enter the scope containing the type, as that is where
5568 the accessibility of types named in dependent bases are
5570 pushed_scope = push_scope (context ? context : global_namespace);
5572 /* Substitute into each of the bases to determine the actual
5574 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5577 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5579 /* Substitute to figure out the base class. */
5580 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5581 if (base == error_mark_node)
5584 base_list = tree_cons (access, base, base_list);
5585 if (BINFO_VIRTUAL_P (pbase_binfo))
5586 TREE_TYPE (base_list) = integer_type_node;
5589 /* The list is now in reverse order; correct that. */
5590 base_list = nreverse (base_list);
5593 pop_scope (pushed_scope);
5595 /* Now call xref_basetypes to set up all the base-class
5597 xref_basetypes (type, base_list);
5600 /* Now that our base classes are set up, enter the scope of the
5601 class, so that name lookups into base classes, etc. will work
5602 correctly. This is precisely analogous to what we do in
5603 begin_class_definition when defining an ordinary non-template
5607 /* Now members are processed in the order of declaration. */
5608 for (member = CLASSTYPE_DECL_LIST (pattern);
5609 member; member = TREE_CHAIN (member))
5611 tree t = TREE_VALUE (member);
5613 if (TREE_PURPOSE (member))
5617 /* Build new CLASSTYPE_NESTED_UTDS. */
5620 tree name = TYPE_IDENTIFIER (tag);
5622 bool class_template_p;
5624 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5625 && TYPE_LANG_SPECIFIC (tag)
5626 && CLASSTYPE_IS_TEMPLATE (tag));
5627 /* If the member is a class template, then -- even after
5628 substitution -- there may be dependent types in the
5629 template argument list for the class. We increment
5630 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5631 that function will assume that no types are dependent
5632 when outside of a template. */
5633 if (class_template_p)
5634 ++processing_template_decl;
5635 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5636 if (class_template_p)
5637 --processing_template_decl;
5638 if (newtag == error_mark_node)
5641 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5643 if (class_template_p)
5644 /* Unfortunately, lookup_template_class sets
5645 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5646 instantiation (i.e., for the type of a member
5647 template class nested within a template class.)
5648 This behavior is required for
5649 maybe_process_partial_specialization to work
5650 correctly, but is not accurate in this case;
5651 the TAG is not an instantiation of anything.
5652 (The corresponding TEMPLATE_DECL is an
5653 instantiation, but the TYPE is not.) */
5654 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5656 /* Now, we call pushtag to put this NEWTAG into the scope of
5657 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5658 pushtag calling push_template_decl. We don't have to do
5659 this for enums because it will already have been done in
5662 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5663 pushtag (name, newtag, /*tag_scope=*/ts_current);
5666 else if (TREE_CODE (t) == FUNCTION_DECL
5667 || DECL_FUNCTION_TEMPLATE_P (t))
5669 /* Build new TYPE_METHODS. */
5672 if (TREE_CODE (t) == TEMPLATE_DECL)
5673 ++processing_template_decl;
5674 r = tsubst (t, args, tf_error, NULL_TREE);
5675 if (TREE_CODE (t) == TEMPLATE_DECL)
5676 --processing_template_decl;
5677 set_current_access_from_decl (r);
5678 grok_special_member_properties (r);
5679 finish_member_declaration (r);
5683 /* Build new TYPE_FIELDS. */
5685 if (TREE_CODE (t) != CONST_DECL)
5689 /* The the file and line for this declaration, to
5690 assist in error message reporting. Since we
5691 called push_tinst_level above, we don't need to
5693 input_location = DECL_SOURCE_LOCATION (t);
5695 if (TREE_CODE (t) == TEMPLATE_DECL)
5696 ++processing_template_decl;
5697 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5698 if (TREE_CODE (t) == TEMPLATE_DECL)
5699 --processing_template_decl;
5700 if (TREE_CODE (r) == VAR_DECL)
5704 [t]he initialization (and any associated
5705 side-effects) of a static data member does
5706 not occur unless the static data member is
5707 itself used in a way that requires the
5708 definition of the static data member to
5711 Therefore, we do not substitute into the
5712 initialized for the static data member here. */
5713 finish_static_data_member_decl
5716 /*asmspec_tree=*/NULL_TREE,
5718 if (DECL_INITIALIZED_IN_CLASS_P (r))
5719 check_static_variable_definition (r, TREE_TYPE (r));
5721 else if (TREE_CODE (r) == FIELD_DECL)
5723 /* Determine whether R has a valid type and can be
5724 completed later. If R is invalid, then it is
5725 replaced by error_mark_node so that it will not be
5726 added to TYPE_FIELDS. */
5727 tree rtype = TREE_TYPE (r);
5728 if (can_complete_type_without_circularity (rtype))
5729 complete_type (rtype);
5731 if (!COMPLETE_TYPE_P (rtype))
5733 cxx_incomplete_type_error (r, rtype);
5734 r = error_mark_node;
5738 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5739 such a thing will already have been added to the field
5740 list by tsubst_enum in finish_member_declaration in the
5741 CLASSTYPE_NESTED_UTDS case above. */
5742 if (!(TREE_CODE (r) == TYPE_DECL
5743 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5744 && DECL_ARTIFICIAL (r)))
5746 set_current_access_from_decl (r);
5747 finish_member_declaration (r);
5754 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5756 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5758 tree friend_type = t;
5759 bool adjust_processing_template_decl = false;
5761 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5763 /* template <class T> friend class C; */
5764 friend_type = tsubst_friend_class (friend_type, args);
5765 adjust_processing_template_decl = true;
5767 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5769 /* template <class T> friend class C::D; */
5770 friend_type = tsubst (friend_type, args,
5771 tf_error | tf_warning, NULL_TREE);
5772 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5773 friend_type = TREE_TYPE (friend_type);
5774 adjust_processing_template_decl = true;
5776 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5778 /* This could be either
5782 when dependent_type_p is false or
5784 template <class U> friend class T::C;
5787 friend_type = tsubst (friend_type, args,
5788 tf_error | tf_warning, NULL_TREE);
5789 /* Bump processing_template_decl for correct
5790 dependent_type_p calculation. */
5791 ++processing_template_decl;
5792 if (dependent_type_p (friend_type))
5793 adjust_processing_template_decl = true;
5794 --processing_template_decl;
5796 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
5797 && hidden_name_p (TYPE_NAME (friend_type)))
5801 where C hasn't been declared yet. Let's lookup name
5802 from namespace scope directly, bypassing any name that
5803 come from dependent base class. */
5804 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5806 /* The call to xref_tag_from_type does injection for friend
5808 push_nested_namespace (ns);
5810 xref_tag_from_type (friend_type, NULL_TREE,
5811 /*tag_scope=*/ts_current);
5812 pop_nested_namespace (ns);
5814 else if (uses_template_parms (friend_type))
5815 /* friend class C<T>; */
5816 friend_type = tsubst (friend_type, args,
5817 tf_error | tf_warning, NULL_TREE);
5822 where C is already declared or
5824 friend class C<int>;
5826 We don't have to do anything in these cases. */
5828 if (adjust_processing_template_decl)
5829 /* Trick make_friend_class into realizing that the friend
5830 we're adding is a template, not an ordinary class. It's
5831 important that we use make_friend_class since it will
5832 perform some error-checking and output cross-reference
5834 ++processing_template_decl;
5836 if (friend_type != error_mark_node)
5837 make_friend_class (type, friend_type, /*complain=*/false);
5839 if (adjust_processing_template_decl)
5840 --processing_template_decl;
5844 /* Build new DECL_FRIENDLIST. */
5847 /* The the file and line for this declaration, to
5848 assist in error message reporting. Since we
5849 called push_tinst_level above, we don't need to
5851 input_location = DECL_SOURCE_LOCATION (t);
5853 if (TREE_CODE (t) == TEMPLATE_DECL)
5855 ++processing_template_decl;
5856 push_deferring_access_checks (dk_no_check);
5859 r = tsubst_friend_function (t, args);
5860 add_friend (type, r, /*complain=*/false);
5861 if (TREE_CODE (t) == TEMPLATE_DECL)
5863 pop_deferring_access_checks ();
5864 --processing_template_decl;
5870 /* Set the file and line number information to whatever is given for
5871 the class itself. This puts error messages involving generated
5872 implicit functions at a predictable point, and the same point
5873 that would be used for non-template classes. */
5874 input_location = DECL_SOURCE_LOCATION (typedecl);
5876 unreverse_member_declarations (type);
5877 finish_struct_1 (type);
5878 TYPE_BEING_DEFINED (type) = 0;
5880 /* Now that the class is complete, instantiate default arguments for
5881 any member functions. We don't do this earlier because the
5882 default arguments may reference members of the class. */
5883 if (!PRIMARY_TEMPLATE_P (template))
5884 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5885 if (TREE_CODE (t) == FUNCTION_DECL
5886 /* Implicitly generated member functions will not have template
5887 information; they are not instantiations, but instead are
5888 created "fresh" for each instantiation. */
5889 && DECL_TEMPLATE_INFO (t))
5890 tsubst_default_arguments (t);
5893 pop_from_top_level ();
5894 pop_deferring_access_checks ();
5897 /* The vtable for a template class can be emitted in any translation
5898 unit in which the class is instantiated. When there is no key
5899 method, however, finish_struct_1 will already have added TYPE to
5900 the keyed_classes list. */
5901 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5902 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5908 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5914 else if (TYPE_P (t))
5915 r = tsubst (t, args, complain, in_decl);
5918 r = tsubst_expr (t, args, complain, in_decl);
5920 if (!uses_template_parms (r))
5922 /* Sometimes, one of the args was an expression involving a
5923 template constant parameter, like N - 1. Now that we've
5924 tsubst'd, we might have something like 2 - 1. This will
5925 confuse lookup_template_class, so we do constant folding
5926 here. We have to unset processing_template_decl, to fool
5927 tsubst_copy_and_build() into building an actual tree. */
5929 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5930 as simple as it's going to get, and trying to reprocess
5931 the trees will break. Once tsubst_expr et al DTRT for
5932 non-dependent exprs, this code can go away, as the type
5933 will always be set. */
5936 int saved_processing_template_decl = processing_template_decl;
5937 processing_template_decl = 0;
5938 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5939 tf_error, /*in_decl=*/NULL_TREE,
5940 /*function_p=*/false);
5941 processing_template_decl = saved_processing_template_decl;
5949 /* Substitute ARGS into the vector or list of template arguments T. */
5952 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5954 int len = TREE_VEC_LENGTH (t);
5955 int need_new = 0, i;
5956 tree *elts = alloca (len * sizeof (tree));
5958 for (i = 0; i < len; i++)
5960 tree orig_arg = TREE_VEC_ELT (t, i);
5963 if (TREE_CODE (orig_arg) == TREE_VEC)
5964 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5966 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5968 if (new_arg == error_mark_node)
5969 return error_mark_node;
5972 if (new_arg != orig_arg)
5979 t = make_tree_vec (len);
5980 for (i = 0; i < len; i++)
5981 TREE_VEC_ELT (t, i) = elts[i];
5986 /* Return the result of substituting ARGS into the template parameters
5987 given by PARMS. If there are m levels of ARGS and m + n levels of
5988 PARMS, then the result will contain n levels of PARMS. For
5989 example, if PARMS is `template <class T> template <class U>
5990 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5991 result will be `template <int*, double, class V>'. */
5994 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5999 for (new_parms = &r;
6000 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
6001 new_parms = &(TREE_CHAIN (*new_parms)),
6002 parms = TREE_CHAIN (parms))
6005 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
6008 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
6010 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
6011 tree default_value = TREE_PURPOSE (tuple);
6012 tree parm_decl = TREE_VALUE (tuple);
6014 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
6015 if (TREE_CODE (parm_decl) == PARM_DECL
6016 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
6017 parm_decl = error_mark_node;
6018 default_value = tsubst_template_arg (default_value, args,
6019 complain, NULL_TREE);
6021 tuple = build_tree_list (default_value, parm_decl);
6022 TREE_VEC_ELT (new_vec, i) = tuple;
6026 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6027 - TMPL_ARGS_DEPTH (args)),
6028 new_vec, NULL_TREE);
6034 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6035 type T. If T is not an aggregate or enumeration type, it is
6036 handled as if by tsubst. IN_DECL is as for tsubst. If
6037 ENTERING_SCOPE is nonzero, T is the context for a template which
6038 we are presently tsubst'ing. Return the substituted value. */
6041 tsubst_aggr_type (tree t,
6043 tsubst_flags_t complain,
6050 switch (TREE_CODE (t))
6053 if (TYPE_PTRMEMFUNC_P (t))
6054 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6056 /* Else fall through. */
6059 if (TYPE_TEMPLATE_INFO (t))
6065 /* First, determine the context for the type we are looking
6067 context = TYPE_CONTEXT (t);
6069 context = tsubst_aggr_type (context, args, complain,
6070 in_decl, /*entering_scope=*/1);
6072 /* Then, figure out what arguments are appropriate for the
6073 type we are trying to find. For example, given:
6075 template <class T> struct S;
6076 template <class T, class U> void f(T, U) { S<U> su; }
6078 and supposing that we are instantiating f<int, double>,
6079 then our ARGS will be {int, double}, but, when looking up
6080 S we only want {double}. */
6081 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6083 if (argvec == error_mark_node)
6084 return error_mark_node;
6086 r = lookup_template_class (t, argvec, in_decl, context,
6087 entering_scope, complain);
6089 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6092 /* This is not a template type, so there's nothing to do. */
6096 return tsubst (t, args, complain, in_decl);
6100 /* Substitute into the default argument ARG (a default argument for
6101 FN), which has the indicated TYPE. */
6104 tsubst_default_argument (tree fn, tree type, tree arg)
6106 tree saved_class_ptr = NULL_TREE;
6107 tree saved_class_ref = NULL_TREE;
6109 /* This default argument came from a template. Instantiate the
6110 default argument here, not in tsubst. In the case of
6119 we must be careful to do name lookup in the scope of S<T>,
6120 rather than in the current class. */
6121 push_access_scope (fn);
6122 /* The default argument expression should not be considered to be
6123 within the scope of FN. Since push_access_scope sets
6124 current_function_decl, we must explicitly clear it here. */
6125 current_function_decl = NULL_TREE;
6126 /* The "this" pointer is not valid in a default argument. */
6129 saved_class_ptr = current_class_ptr;
6130 cp_function_chain->x_current_class_ptr = NULL_TREE;
6131 saved_class_ref = current_class_ref;
6132 cp_function_chain->x_current_class_ref = NULL_TREE;
6135 push_deferring_access_checks(dk_no_deferred);
6136 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6137 tf_error | tf_warning, NULL_TREE);
6138 pop_deferring_access_checks();
6140 /* Restore the "this" pointer. */
6143 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6144 cp_function_chain->x_current_class_ref = saved_class_ref;
6147 pop_access_scope (fn);
6149 /* Make sure the default argument is reasonable. */
6150 arg = check_default_argument (type, arg);
6155 /* Substitute into all the default arguments for FN. */
6158 tsubst_default_arguments (tree fn)
6163 tmpl_args = DECL_TI_ARGS (fn);
6165 /* If this function is not yet instantiated, we certainly don't need
6166 its default arguments. */
6167 if (uses_template_parms (tmpl_args))
6170 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6172 arg = TREE_CHAIN (arg))
6173 if (TREE_PURPOSE (arg))
6174 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6176 TREE_PURPOSE (arg));
6179 /* Substitute the ARGS into the T, which is a _DECL. Return the
6180 result of the substitution. Issue error and warning messages under
6181 control of COMPLAIN. */
6184 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6186 location_t saved_loc;
6190 /* Set the filename and linenumber to improve error-reporting. */
6191 saved_loc = input_location;
6192 input_location = DECL_SOURCE_LOCATION (t);
6194 switch (TREE_CODE (t))
6198 /* We can get here when processing a member function template,
6199 member class template, and template template parameter of
6200 a template class. */
6201 tree decl = DECL_TEMPLATE_RESULT (t);
6206 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6208 /* Template template parameter is treated here. */
6209 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6210 if (new_type == error_mark_node)
6211 return error_mark_node;
6214 TREE_CHAIN (r) = NULL_TREE;
6215 TREE_TYPE (r) = new_type;
6216 DECL_TEMPLATE_RESULT (r)
6217 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6218 DECL_TEMPLATE_PARMS (r)
6219 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6221 TYPE_NAME (new_type) = r;
6225 /* We might already have an instance of this template.
6226 The ARGS are for the surrounding class type, so the
6227 full args contain the tsubst'd args for the context,
6228 plus the innermost args from the template decl. */
6229 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6230 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6231 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6232 full_args = tsubst_template_args (tmpl_args, args,
6234 if (full_args == error_mark_node)
6235 return error_mark_node;
6237 /* tsubst_template_args doesn't copy the vector if
6238 nothing changed. But, *something* should have
6240 gcc_assert (full_args != tmpl_args);
6242 spec = retrieve_specialization (t, full_args,
6243 /*class_specializations_p=*/true);
6244 if (spec != NULL_TREE)
6250 /* Make a new template decl. It will be similar to the
6251 original, but will record the current template arguments.
6252 We also create a new function declaration, which is just
6253 like the old one, but points to this new template, rather
6254 than the old one. */
6256 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6257 TREE_CHAIN (r) = NULL_TREE;
6260 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6262 /*entering_scope=*/1);
6263 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6265 if (TREE_CODE (decl) == TYPE_DECL)
6267 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6268 if (new_type == error_mark_node)
6269 return error_mark_node;
6271 TREE_TYPE (r) = new_type;
6272 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6273 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6274 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6278 tree new_decl = tsubst (decl, args, complain, in_decl);
6279 if (new_decl == error_mark_node)
6280 return error_mark_node;
6282 DECL_TEMPLATE_RESULT (r) = new_decl;
6283 DECL_TI_TEMPLATE (new_decl) = r;
6284 TREE_TYPE (r) = TREE_TYPE (new_decl);
6285 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6288 SET_DECL_IMPLICIT_INSTANTIATION (r);
6289 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6290 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6292 /* The template parameters for this new template are all the
6293 template parameters for the old template, except the
6294 outermost level of parameters. */
6295 DECL_TEMPLATE_PARMS (r)
6296 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6299 if (PRIMARY_TEMPLATE_P (t))
6300 DECL_PRIMARY_TEMPLATE (r) = r;
6302 if (TREE_CODE (decl) != TYPE_DECL)
6303 /* Record this non-type partial instantiation. */
6304 register_specialization (r, t,
6305 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
6312 tree argvec = NULL_TREE;
6320 /* Nobody should be tsubst'ing into non-template functions. */
6321 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6323 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6328 /* If T is not dependent, just return it. We have to
6329 increment PROCESSING_TEMPLATE_DECL because
6330 value_dependent_expression_p assumes that nothing is
6331 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6332 ++processing_template_decl;
6333 dependent_p = value_dependent_expression_p (t);
6334 --processing_template_decl;
6338 /* Calculate the most general template of which R is a
6339 specialization, and the complete set of arguments used to
6341 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6342 argvec = tsubst_template_args (DECL_TI_ARGS
6343 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6344 args, complain, in_decl);
6346 /* Check to see if we already have this specialization. */
6347 spec = retrieve_specialization (gen_tmpl, argvec,
6348 /*class_specializations_p=*/false);
6356 /* We can see more levels of arguments than parameters if
6357 there was a specialization of a member template, like
6360 template <class T> struct S { template <class U> void f(); }
6361 template <> template <class U> void S<int>::f(U);
6363 Here, we'll be substituting into the specialization,
6364 because that's where we can find the code we actually
6365 want to generate, but we'll have enough arguments for
6366 the most general template.
6368 We also deal with the peculiar case:
6370 template <class T> struct S {
6371 template <class U> friend void f();
6373 template <class U> void f() {}
6375 template void f<double>();
6377 Here, the ARGS for the instantiation of will be {int,
6378 double}. But, we only need as many ARGS as there are
6379 levels of template parameters in CODE_PATTERN. We are
6380 careful not to get fooled into reducing the ARGS in
6383 template <class T> struct S { template <class U> void f(U); }
6384 template <class T> template <> void S<T>::f(int) {}
6386 which we can spot because the pattern will be a
6387 specialization in this case. */
6388 args_depth = TMPL_ARGS_DEPTH (args);
6390 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6391 if (args_depth > parms_depth
6392 && !DECL_TEMPLATE_SPECIALIZATION (t))
6393 args = get_innermost_template_args (args, parms_depth);
6397 /* This special case arises when we have something like this:
6399 template <class T> struct S {
6400 friend void f<int>(int, double);
6403 Here, the DECL_TI_TEMPLATE for the friend declaration
6404 will be an IDENTIFIER_NODE. We are being called from
6405 tsubst_friend_function, and we want only to create a
6406 new decl (R) with appropriate types so that we can call
6407 determine_specialization. */
6408 gen_tmpl = NULL_TREE;
6411 if (DECL_CLASS_SCOPE_P (t))
6413 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6417 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6418 complain, t, /*entering_scope=*/1);
6423 ctx = DECL_CONTEXT (t);
6425 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6426 if (type == error_mark_node)
6427 return error_mark_node;
6429 /* We do NOT check for matching decls pushed separately at this
6430 point, as they may not represent instantiations of this
6431 template, and in any case are considered separate under the
6434 DECL_USE_TEMPLATE (r) = 0;
6435 TREE_TYPE (r) = type;
6436 /* Clear out the mangled name and RTL for the instantiation. */
6437 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6438 SET_DECL_RTL (r, NULL_RTX);
6439 DECL_INITIAL (r) = NULL_TREE;
6440 DECL_CONTEXT (r) = ctx;
6442 if (member && DECL_CONV_FN_P (r))
6443 /* Type-conversion operator. Reconstruct the name, in
6444 case it's the name of one of the template's parameters. */
6445 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6447 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6449 DECL_RESULT (r) = NULL_TREE;
6451 TREE_STATIC (r) = 0;
6452 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6453 DECL_EXTERNAL (r) = 1;
6454 /* If this is an instantiation of a function with internal
6455 linkage, we already know what object file linkage will be
6456 assigned to the instantiation. */
6457 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6458 DECL_DEFER_OUTPUT (r) = 0;
6459 TREE_CHAIN (r) = NULL_TREE;
6460 DECL_PENDING_INLINE_INFO (r) = 0;
6461 DECL_PENDING_INLINE_P (r) = 0;
6462 DECL_SAVED_TREE (r) = NULL_TREE;
6464 if (DECL_CLONED_FUNCTION (r))
6466 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6468 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6469 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6472 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6473 this in the special friend case mentioned above where
6474 GEN_TMPL is NULL. */
6477 DECL_TEMPLATE_INFO (r)
6478 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6479 SET_DECL_IMPLICIT_INSTANTIATION (r);
6480 register_specialization (r, gen_tmpl, argvec);
6482 /* We're not supposed to instantiate default arguments
6483 until they are called, for a template. But, for a
6486 template <class T> void f ()
6487 { extern void g(int i = T()); }
6489 we should do the substitution when the template is
6490 instantiated. We handle the member function case in
6491 instantiate_class_template since the default arguments
6492 might refer to other members of the class. */
6494 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6495 && !uses_template_parms (argvec))
6496 tsubst_default_arguments (r);
6499 /* Copy the list of befriending classes. */
6500 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6502 friends = &TREE_CHAIN (*friends))
6504 *friends = copy_node (*friends);
6505 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6510 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6512 maybe_retrofit_in_chrg (r);
6513 if (DECL_CONSTRUCTOR_P (r))
6514 grok_ctor_properties (ctx, r);
6515 /* If this is an instantiation of a member template, clone it.
6516 If it isn't, that'll be handled by
6517 clone_constructors_and_destructors. */
6518 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6519 clone_function_decl (r, /*update_method_vec_p=*/0);
6521 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6522 grok_op_properties (r, (complain & tf_error) != 0);
6524 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6525 SET_DECL_FRIEND_CONTEXT (r,
6526 tsubst (DECL_FRIEND_CONTEXT (t),
6527 args, complain, in_decl));
6536 if (DECL_TEMPLATE_PARM_P (t))
6537 SET_DECL_TEMPLATE_PARM_P (r);
6539 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6540 type = type_decays_to (type);
6541 TREE_TYPE (r) = type;
6542 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6544 if (DECL_INITIAL (r))
6546 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6547 DECL_INITIAL (r) = TREE_TYPE (r);
6549 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6553 DECL_CONTEXT (r) = NULL_TREE;
6555 if (!DECL_TEMPLATE_PARM_P (r))
6556 DECL_ARG_TYPE (r) = type_passed_as (type);
6558 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6559 complain, TREE_CHAIN (t));
6568 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6569 if (type == error_mark_node)
6570 return error_mark_node;
6571 TREE_TYPE (r) = type;
6572 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6574 /* We don't have to set DECL_CONTEXT here; it is set by
6575 finish_member_declaration. */
6576 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6578 TREE_CHAIN (r) = NULL_TREE;
6579 if (VOID_TYPE_P (type))
6580 error ("instantiation of %q+D as type %qT", r, type);
6585 /* We reach here only for member using decls. */
6586 if (DECL_DEPENDENT_P (t))
6588 r = do_class_using_decl
6589 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
6590 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
6592 r = error_mark_node;
6597 TREE_CHAIN (r) = NULL_TREE;
6604 tree argvec = NULL_TREE;
6605 tree gen_tmpl = NULL_TREE;
6607 tree tmpl = NULL_TREE;
6609 tree type = NULL_TREE;
6612 if (TREE_CODE (t) == TYPE_DECL)
6614 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6615 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6616 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6618 /* If this is the canonical decl, we don't have to
6619 mess with instantiations, and often we can't (for
6620 typename, template type parms and such). Note that
6621 TYPE_NAME is not correct for the above test if
6622 we've copied the type for a typedef. */
6623 r = TYPE_NAME (type);
6628 /* Assume this is a non-local variable. */
6631 if (TYPE_P (CP_DECL_CONTEXT (t)))
6632 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6634 in_decl, /*entering_scope=*/1);
6635 else if (DECL_NAMESPACE_SCOPE_P (t))
6636 ctx = DECL_CONTEXT (t);
6639 /* Subsequent calls to pushdecl will fill this in. */
6644 /* Check to see if we already have this specialization. */
6647 tmpl = DECL_TI_TEMPLATE (t);
6648 gen_tmpl = most_general_template (tmpl);
6649 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6650 spec = retrieve_specialization (gen_tmpl, argvec,
6651 /*class_specializations_p=*/false);
6654 spec = retrieve_local_specialization (t);
6663 if (TREE_CODE (r) == VAR_DECL)
6665 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6666 if (type == error_mark_node)
6667 return error_mark_node;
6668 type = complete_type (type);
6669 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6670 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6671 type = check_var_type (DECL_NAME (r), type);
6673 else if (DECL_SELF_REFERENCE_P (t))
6674 SET_DECL_SELF_REFERENCE_P (r);
6675 TREE_TYPE (r) = type;
6676 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6677 DECL_CONTEXT (r) = ctx;
6678 /* Clear out the mangled name and RTL for the instantiation. */
6679 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6680 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6681 SET_DECL_RTL (r, NULL_RTX);
6683 /* Don't try to expand the initializer until someone tries to use
6684 this variable; otherwise we run into circular dependencies. */
6685 DECL_INITIAL (r) = NULL_TREE;
6686 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6687 SET_DECL_RTL (r, NULL_RTX);
6688 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6690 /* Even if the original location is out of scope, the newly
6691 substituted one is not. */
6692 if (TREE_CODE (r) == VAR_DECL)
6694 DECL_DEAD_FOR_LOCAL (r) = 0;
6695 DECL_INITIALIZED_P (r) = 0;
6700 /* A static data member declaration is always marked
6701 external when it is declared in-class, even if an
6702 initializer is present. We mimic the non-template
6704 DECL_EXTERNAL (r) = 1;
6706 register_specialization (r, gen_tmpl, argvec);
6707 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6708 SET_DECL_IMPLICIT_INSTANTIATION (r);
6711 register_local_specialization (r, t);
6713 TREE_CHAIN (r) = NULL_TREE;
6722 /* Restore the file and line information. */
6723 input_location = saved_loc;
6728 /* Substitute into the ARG_TYPES of a function type. */
6731 tsubst_arg_types (tree arg_types,
6733 tsubst_flags_t complain,
6736 tree remaining_arg_types;
6739 tree result = NULL_TREE;
6741 if (!arg_types || arg_types == void_list_node)
6744 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6745 args, complain, in_decl);
6746 if (remaining_arg_types == error_mark_node)
6747 return error_mark_node;
6749 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6750 if (type == error_mark_node)
6751 return error_mark_node;
6752 if (VOID_TYPE_P (type))
6754 if (complain & tf_error)
6756 error ("invalid parameter type %qT", type);
6758 error ("in declaration %q+D", in_decl);
6760 return error_mark_node;
6763 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6764 top-level qualifiers as required. */
6765 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6767 /* We do not substitute into default arguments here. The standard
6768 mandates that they be instantiated only when needed, which is
6769 done in build_over_call. */
6770 default_arg = TREE_PURPOSE (arg_types);
6772 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
6774 /* We've instantiated a template before its default arguments
6775 have been parsed. This can happen for a nested template
6776 class, and is not an error unless we require the default
6777 argument in a call of this function. */
6778 result = tree_cons (default_arg, type, remaining_arg_types);
6779 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), result);
6782 result = hash_tree_cons (default_arg, type, remaining_arg_types);
6787 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6788 *not* handle the exception-specification for FNTYPE, because the
6789 initial substitution of explicitly provided template parameters
6790 during argument deduction forbids substitution into the
6791 exception-specification:
6795 All references in the function type of the function template to the
6796 corresponding template parameters are replaced by the specified tem-
6797 plate argument values. If a substitution in a template parameter or
6798 in the function type of the function template results in an invalid
6799 type, type deduction fails. [Note: The equivalent substitution in
6800 exception specifications is done only when the function is instanti-
6801 ated, at which point a program is ill-formed if the substitution
6802 results in an invalid type.] */
6805 tsubst_function_type (tree t,
6807 tsubst_flags_t complain,
6814 /* The TYPE_CONTEXT is not used for function/method types. */
6815 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6817 /* Substitute the return type. */
6818 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6819 if (return_type == error_mark_node)
6820 return error_mark_node;
6821 /* The standard does not presently indicate that creation of a
6822 function type with an invalid return type is a deduction failure.
6823 However, that is clearly analogous to creating an array of "void"
6824 or a reference to a reference. This is core issue #486. */
6825 if (TREE_CODE (return_type) == ARRAY_TYPE
6826 || TREE_CODE (return_type) == FUNCTION_TYPE)
6828 if (complain & tf_error)
6830 if (TREE_CODE (return_type) == ARRAY_TYPE)
6831 error ("function returning an array");
6833 error ("function returning a function");
6835 return error_mark_node;
6838 /* Substitute the argument types. */
6839 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6841 if (arg_types == error_mark_node)
6842 return error_mark_node;
6844 /* Construct a new type node and return it. */
6845 if (TREE_CODE (t) == FUNCTION_TYPE)
6846 fntype = build_function_type (return_type, arg_types);
6849 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6850 if (! IS_AGGR_TYPE (r))
6854 Type deduction may fail for any of the following
6857 -- Attempting to create "pointer to member of T" when T
6858 is not a class type. */
6859 if (complain & tf_error)
6860 error ("creating pointer to member function of non-class type %qT",
6862 return error_mark_node;
6865 fntype = build_method_type_directly (r, return_type,
6866 TREE_CHAIN (arg_types));
6868 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6869 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6874 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6875 ARGS into that specification, and return the substituted
6876 specification. If there is no specification, return NULL_TREE. */
6879 tsubst_exception_specification (tree fntype,
6881 tsubst_flags_t complain,
6887 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6888 new_specs = NULL_TREE;
6891 if (! TREE_VALUE (specs))
6897 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6898 if (spec == error_mark_node)
6900 new_specs = add_exception_specifier (new_specs, spec, complain);
6901 specs = TREE_CHAIN (specs);
6907 /* Substitute into the PARMS of a call-declarator. */
6910 tsubst_call_declarator_parms (tree parms,
6912 tsubst_flags_t complain,
6919 if (!parms || parms == void_list_node)
6922 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6923 args, complain, in_decl);
6925 /* Figure out the type of this parameter. */
6926 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6928 /* Figure out the default argument as well. Note that we use
6929 tsubst_expr since the default argument is really an expression. */
6930 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6932 /* Chain this parameter on to the front of those we have already
6933 processed. We don't use hash_tree_cons because that function
6934 doesn't check TREE_PARMLIST. */
6935 new_parms = tree_cons (defarg, type, new_parms);
6940 /* Take the tree structure T and replace template parameters used
6941 therein with the argument vector ARGS. IN_DECL is an associated
6942 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6943 Issue error and warning messages under control of COMPLAIN. Note
6944 that we must be relatively non-tolerant of extensions here, in
6945 order to preserve conformance; if we allow substitutions that
6946 should not be allowed, we may allow argument deductions that should
6947 not succeed, and therefore report ambiguous overload situations
6948 where there are none. In theory, we could allow the substitution,
6949 but indicate that it should have failed, and allow our caller to
6950 make sure that the right thing happens, but we don't try to do this
6953 This function is used for dealing with types, decls and the like;
6954 for expressions, use tsubst_expr or tsubst_copy. */
6957 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6961 if (t == NULL_TREE || t == error_mark_node
6962 || t == integer_type_node
6963 || t == void_type_node
6964 || t == char_type_node
6965 || t == unknown_type_node
6966 || TREE_CODE (t) == NAMESPACE_DECL)
6970 return tsubst_decl (t, args, complain);
6972 if (TREE_CODE (t) == IDENTIFIER_NODE)
6973 type = IDENTIFIER_TYPE_VALUE (t);
6975 type = TREE_TYPE (t);
6977 gcc_assert (type != unknown_type_node);
6980 && TREE_CODE (t) != TYPENAME_TYPE
6981 && TREE_CODE (t) != IDENTIFIER_NODE
6982 && TREE_CODE (t) != FUNCTION_TYPE
6983 && TREE_CODE (t) != METHOD_TYPE)
6984 type = tsubst (type, args, complain, in_decl);
6985 if (type == error_mark_node)
6986 return error_mark_node;
6988 switch (TREE_CODE (t))
6993 return tsubst_aggr_type (t, args, complain, in_decl,
6994 /*entering_scope=*/0);
6997 case IDENTIFIER_NODE:
7009 if (t == integer_type_node)
7012 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
7013 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
7017 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
7019 /* The array dimension behaves like a non-type template arg,
7020 in that we want to fold it as much as possible. */
7021 max = tsubst_template_arg (omax, args, complain, in_decl);
7022 max = fold_decl_constant_value (max);
7024 if (integer_zerop (omax))
7026 /* Still allow an explicit array of size zero. */
7028 pedwarn ("creating array with size zero");
7030 else if (integer_zerop (max)
7031 || (TREE_CODE (max) == INTEGER_CST
7032 && INT_CST_LT (max, integer_zero_node)))
7036 Type deduction may fail for any of the following
7039 Attempting to create an array with a size that is
7040 zero or negative. */
7041 if (complain & tf_error)
7042 error ("creating array with size zero (%qE)", max);
7044 return error_mark_node;
7047 return compute_array_index_type (NULL_TREE, max);
7050 case TEMPLATE_TYPE_PARM:
7051 case TEMPLATE_TEMPLATE_PARM:
7052 case BOUND_TEMPLATE_TEMPLATE_PARM:
7053 case TEMPLATE_PARM_INDEX:
7058 tree arg = NULL_TREE;
7062 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7063 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7064 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7065 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7067 idx = TEMPLATE_TYPE_IDX (t);
7068 level = TEMPLATE_TYPE_LEVEL (t);
7072 idx = TEMPLATE_PARM_IDX (t);
7073 level = TEMPLATE_PARM_LEVEL (t);
7076 levels = TMPL_ARGS_DEPTH (args);
7077 if (level <= levels)
7078 arg = TMPL_ARG (args, level, idx);
7080 if (arg == error_mark_node)
7081 return error_mark_node;
7082 else if (arg != NULL_TREE)
7084 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7086 gcc_assert (TYPE_P (arg));
7087 return cp_build_qualified_type_real
7088 (arg, cp_type_quals (arg) | cp_type_quals (t),
7089 complain | tf_ignore_bad_quals);
7091 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7093 /* We are processing a type constructed from a
7094 template template parameter. */
7095 tree argvec = tsubst (TYPE_TI_ARGS (t),
7096 args, complain, in_decl);
7097 if (argvec == error_mark_node)
7098 return error_mark_node;
7100 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7101 are resolving nested-types in the signature of a
7102 member function templates. Otherwise ARG is a
7103 TEMPLATE_DECL and is the real template to be
7105 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7106 arg = TYPE_NAME (arg);
7108 r = lookup_template_class (arg,
7111 /*entering_scope=*/0,
7113 return cp_build_qualified_type_real
7114 (r, TYPE_QUALS (t), complain);
7117 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7122 /* This can happen during the attempted tsubst'ing in
7123 unify. This means that we don't yet have any information
7124 about the template parameter in question. */
7127 /* If we get here, we must have been looking at a parm for a
7128 more deeply nested template. Make a new version of this
7129 template parameter, but with a lower level. */
7130 switch (TREE_CODE (t))
7132 case TEMPLATE_TYPE_PARM:
7133 case TEMPLATE_TEMPLATE_PARM:
7134 case BOUND_TEMPLATE_TEMPLATE_PARM:
7135 if (cp_type_quals (t))
7137 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7138 r = cp_build_qualified_type_real
7139 (r, cp_type_quals (t),
7140 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7141 ? tf_ignore_bad_quals : 0));
7146 TEMPLATE_TYPE_PARM_INDEX (r)
7147 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7149 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7150 TYPE_MAIN_VARIANT (r) = r;
7151 TYPE_POINTER_TO (r) = NULL_TREE;
7152 TYPE_REFERENCE_TO (r) = NULL_TREE;
7154 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7156 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7158 if (argvec == error_mark_node)
7159 return error_mark_node;
7161 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7162 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7167 case TEMPLATE_PARM_INDEX:
7168 r = reduce_template_parm_level (t, type, levels);
7180 tree purpose, value, chain;
7182 if (t == void_list_node)
7185 purpose = TREE_PURPOSE (t);
7188 purpose = tsubst (purpose, args, complain, in_decl);
7189 if (purpose == error_mark_node)
7190 return error_mark_node;
7192 value = TREE_VALUE (t);
7195 value = tsubst (value, args, complain, in_decl);
7196 if (value == error_mark_node)
7197 return error_mark_node;
7199 chain = TREE_CHAIN (t);
7200 if (chain && chain != void_type_node)
7202 chain = tsubst (chain, args, complain, in_decl);
7203 if (chain == error_mark_node)
7204 return error_mark_node;
7206 if (purpose == TREE_PURPOSE (t)
7207 && value == TREE_VALUE (t)
7208 && chain == TREE_CHAIN (t))
7210 return hash_tree_cons (purpose, value, chain);
7214 /* We should never be tsubsting a binfo. */
7218 /* A vector of template arguments. */
7220 return tsubst_template_args (t, args, complain, in_decl);
7223 case REFERENCE_TYPE:
7225 enum tree_code code;
7227 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7230 code = TREE_CODE (t);
7235 Type deduction may fail for any of the following
7238 -- Attempting to create a pointer to reference type.
7239 -- Attempting to create a reference to a reference type or
7240 a reference to void. */
7241 if (TREE_CODE (type) == REFERENCE_TYPE
7242 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7244 static location_t last_loc;
7246 /* We keep track of the last time we issued this error
7247 message to avoid spewing a ton of messages during a
7248 single bad template instantiation. */
7249 if (complain & tf_error
7250 #ifdef USE_MAPPED_LOCATION
7251 && last_loc != input_location
7253 && (last_loc.line != input_line
7254 || last_loc.file != input_filename)
7258 if (TREE_CODE (type) == VOID_TYPE)
7259 error ("forming reference to void");
7261 error ("forming %s to reference type %qT",
7262 (code == POINTER_TYPE) ? "pointer" : "reference",
7264 last_loc = input_location;
7267 return error_mark_node;
7269 else if (code == POINTER_TYPE)
7271 r = build_pointer_type (type);
7272 if (TREE_CODE (type) == METHOD_TYPE)
7273 r = build_ptrmemfunc_type (r);
7276 r = build_reference_type (type);
7277 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7279 if (r != error_mark_node)
7280 /* Will this ever be needed for TYPE_..._TO values? */
7287 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7288 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7292 Type deduction may fail for any of the following
7295 -- Attempting to create "pointer to member of T" when T
7296 is not a class type. */
7297 if (complain & tf_error)
7298 error ("creating pointer to member of non-class type %qT", r);
7299 return error_mark_node;
7301 if (TREE_CODE (type) == REFERENCE_TYPE)
7303 if (complain & tf_error)
7304 error ("creating pointer to member reference type %qT", type);
7305 return error_mark_node;
7307 if (TREE_CODE (type) == VOID_TYPE)
7309 if (complain & tf_error)
7310 error ("creating pointer to member of type void");
7311 return error_mark_node;
7313 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7314 if (TREE_CODE (type) == FUNCTION_TYPE)
7316 /* The type of the implicit object parameter gets its
7317 cv-qualifiers from the FUNCTION_TYPE. */
7319 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
7320 cp_type_quals (type));
7322 method_type = build_method_type_directly (this_type,
7324 TYPE_ARG_TYPES (type));
7325 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
7326 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
7330 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7339 fntype = tsubst_function_type (t, args, complain, in_decl);
7340 if (fntype == error_mark_node)
7341 return error_mark_node;
7343 /* Substitute the exception specification. */
7344 specs = tsubst_exception_specification (t, args, complain,
7346 if (specs == error_mark_node)
7347 return error_mark_node;
7349 fntype = build_exception_variant (fntype, specs);
7354 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7355 if (domain == error_mark_node)
7356 return error_mark_node;
7358 /* As an optimization, we avoid regenerating the array type if
7359 it will obviously be the same as T. */
7360 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7363 /* These checks should match the ones in grokdeclarator.
7367 The deduction may fail for any of the following reasons:
7369 -- Attempting to create an array with an element type that
7370 is void, a function type, or a reference type, or [DR337]
7371 an abstract class type. */
7372 if (TREE_CODE (type) == VOID_TYPE
7373 || TREE_CODE (type) == FUNCTION_TYPE
7374 || TREE_CODE (type) == REFERENCE_TYPE)
7376 if (complain & tf_error)
7377 error ("creating array of %qT", type);
7378 return error_mark_node;
7380 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7382 if (complain & tf_error)
7383 error ("creating array of %qT, which is an abstract class type",
7385 return error_mark_node;
7388 r = build_cplus_array_type (type, domain);
7395 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7396 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7398 if (e1 == error_mark_node || e2 == error_mark_node)
7399 return error_mark_node;
7401 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
7407 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7408 if (e == error_mark_node)
7409 return error_mark_node;
7411 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
7416 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7417 in_decl, /*entering_scope=*/1);
7418 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7421 if (ctx == error_mark_node || f == error_mark_node)
7422 return error_mark_node;
7424 if (!IS_AGGR_TYPE (ctx))
7426 if (complain & tf_error)
7427 error ("%qT is not a class, struct, or union type", ctx);
7428 return error_mark_node;
7430 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7432 /* Normally, make_typename_type does not require that the CTX
7433 have complete type in order to allow things like:
7435 template <class T> struct S { typename S<T>::X Y; };
7437 But, such constructs have already been resolved by this
7438 point, so here CTX really should have complete type, unless
7439 it's a partial instantiation. */
7440 ctx = complete_type (ctx);
7441 if (!COMPLETE_TYPE_P (ctx))
7443 if (complain & tf_error)
7444 cxx_incomplete_type_error (NULL_TREE, ctx);
7445 return error_mark_node;
7449 f = make_typename_type (ctx, f, typename_type,
7450 (complain & tf_error) | tf_keep_type_decl);
7451 if (f == error_mark_node)
7453 if (TREE_CODE (f) == TYPE_DECL)
7455 complain |= tf_ignore_bad_quals;
7459 if (TREE_CODE (f) != TYPENAME_TYPE)
7461 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7462 error ("%qT resolves to %qT, which is not an enumeration type",
7464 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7465 error ("%qT resolves to %qT, which is is not a class type",
7469 return cp_build_qualified_type_real
7470 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7473 case UNBOUND_CLASS_TEMPLATE:
7475 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7476 in_decl, /*entering_scope=*/1);
7477 tree name = TYPE_IDENTIFIER (t);
7478 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7480 if (ctx == error_mark_node || name == error_mark_node)
7481 return error_mark_node;
7484 parm_list = tsubst_template_parms (parm_list, args, complain);
7485 return make_unbound_class_template (ctx, name, parm_list, complain);
7495 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7496 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7497 if (e1 == error_mark_node || e2 == error_mark_node)
7498 return error_mark_node;
7500 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7505 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7506 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7507 if (e1 == error_mark_node || e2 == error_mark_node)
7508 return error_mark_node;
7510 return build_nt (TREE_CODE (t), e1, e2);
7517 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7518 complain, in_decl));
7519 return cp_build_qualified_type_real (type,
7521 | cp_type_quals (type),
7526 sorry ("use of %qs in template",
7527 tree_code_name [(int) TREE_CODE (t)]);
7528 return error_mark_node;
7532 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7533 type of the expression on the left-hand side of the "." or "->"
7537 tsubst_baselink (tree baselink, tree object_type,
7538 tree args, tsubst_flags_t complain, tree in_decl)
7541 tree qualifying_scope;
7543 tree template_args = 0;
7544 bool template_id_p = false;
7546 /* A baselink indicates a function from a base class. The
7547 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7548 non-dependent types; otherwise, the lookup could not have
7549 succeeded. However, they may indicate bases of the template
7550 class, rather than the instantiated class.
7552 In addition, lookups that were not ambiguous before may be
7553 ambiguous now. Therefore, we perform the lookup again. */
7554 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7555 fns = BASELINK_FUNCTIONS (baselink);
7556 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7558 template_id_p = true;
7559 template_args = TREE_OPERAND (fns, 1);
7560 fns = TREE_OPERAND (fns, 0);
7562 template_args = tsubst_template_args (template_args, args,
7565 name = DECL_NAME (get_first_fn (fns));
7566 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7568 /* If lookup found a single function, mark it as used at this
7569 point. (If it lookup found multiple functions the one selected
7570 later by overload resolution will be marked as used at that
7572 if (BASELINK_P (baselink))
7573 fns = BASELINK_FUNCTIONS (baselink);
7574 if (!template_id_p && !really_overloaded_fn (fns))
7575 mark_used (OVL_CURRENT (fns));
7577 /* Add back the template arguments, if present. */
7578 if (BASELINK_P (baselink) && template_id_p)
7579 BASELINK_FUNCTIONS (baselink)
7580 = build_nt (TEMPLATE_ID_EXPR,
7581 BASELINK_FUNCTIONS (baselink),
7585 object_type = current_class_type;
7586 return adjust_result_of_qualified_name_lookup (baselink,
7591 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7592 true if the qualified-id will be a postfix-expression in-and-of
7593 itself; false if more of the postfix-expression follows the
7594 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7598 tsubst_qualified_id (tree qualified_id, tree args,
7599 tsubst_flags_t complain, tree in_decl,
7600 bool done, bool address_p)
7608 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7610 /* Figure out what name to look up. */
7611 name = TREE_OPERAND (qualified_id, 1);
7612 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7615 template_args = TREE_OPERAND (name, 1);
7617 template_args = tsubst_template_args (template_args, args,
7619 name = TREE_OPERAND (name, 0);
7623 is_template = false;
7624 template_args = NULL_TREE;
7627 /* Substitute into the qualifying scope. When there are no ARGS, we
7628 are just trying to simplify a non-dependent expression. In that
7629 case the qualifying scope may be dependent, and, in any case,
7630 substituting will not help. */
7631 scope = TREE_OPERAND (qualified_id, 0);
7634 scope = tsubst (scope, args, complain, in_decl);
7635 expr = tsubst_copy (name, args, complain, in_decl);
7640 if (dependent_type_p (scope))
7641 return build_nt (SCOPE_REF, scope, expr);
7643 if (!BASELINK_P (name) && !DECL_P (expr))
7645 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7646 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7647 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7649 if (complain & tf_error)
7651 error ("dependent-name %qE is parsed as a non-type, but "
7652 "instantiation yields a type", qualified_id);
7653 inform ("say %<typename %E%> if a type is meant", qualified_id);
7655 return error_mark_node;
7661 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7663 /* Remember that there was a reference to this entity. */
7667 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7669 if (complain & tf_error)
7670 qualified_name_lookup_error (scope,
7671 TREE_OPERAND (qualified_id, 1),
7673 return error_mark_node;
7677 expr = lookup_template_function (expr, template_args);
7679 if (expr == error_mark_node && complain & tf_error)
7680 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7682 else if (TYPE_P (scope))
7684 expr = (adjust_result_of_qualified_name_lookup
7685 (expr, scope, current_class_type));
7686 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7689 if (TREE_CODE (expr) != SCOPE_REF)
7690 expr = convert_from_reference (expr);
7695 /* Like tsubst, but deals with expressions. This function just replaces
7696 template parms; to finish processing the resultant expression, use
7700 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7702 enum tree_code code;
7705 if (t == NULL_TREE || t == error_mark_node)
7708 code = TREE_CODE (t);
7713 r = retrieve_local_specialization (t);
7714 gcc_assert (r != NULL);
7723 if (DECL_TEMPLATE_PARM_P (t))
7724 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7725 /* There is no need to substitute into namespace-scope
7727 if (DECL_NAMESPACE_SCOPE_P (t))
7729 /* If ARGS is NULL, then T is known to be non-dependent. */
7730 if (args == NULL_TREE)
7731 return integral_constant_value (t);
7733 /* Unfortunately, we cannot just call lookup_name here.
7736 template <int I> int f() {
7738 struct S { void g() { E e = a; } };
7741 When we instantiate f<7>::S::g(), say, lookup_name is not
7742 clever enough to find f<7>::a. */
7744 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7745 /*entering_scope=*/0);
7747 for (v = TYPE_VALUES (enum_type);
7750 if (TREE_PURPOSE (v) == DECL_NAME (t))
7751 return TREE_VALUE (v);
7753 /* We didn't find the name. That should never happen; if
7754 name-lookup found it during preliminary parsing, we
7755 should find it again here during instantiation. */
7761 if (DECL_CONTEXT (t))
7765 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7766 /*entering_scope=*/1);
7767 if (ctx != DECL_CONTEXT (t))
7769 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7772 if (complain & tf_error)
7773 error ("using invalid field %qD", t);
7774 return error_mark_node;
7784 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7785 || local_variable_p (t))
7786 t = tsubst (t, args, complain, in_decl);
7791 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7794 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7795 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7796 args, complain, in_decl);
7797 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7798 return tsubst (t, args, complain, in_decl);
7799 else if (DECL_CLASS_SCOPE_P (t)
7800 && uses_template_parms (DECL_CONTEXT (t)))
7802 /* Template template argument like the following example need
7805 template <template <class> class TT> struct C {};
7806 template <class T> struct D {
7807 template <class U> struct E {};
7812 We are processing the template argument `E' in #1 for
7813 the template instantiation #2. Originally, `E' is a
7814 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7815 have to substitute this with one having context `D<int>'. */
7817 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7818 return lookup_field (context, DECL_NAME(t), 0, false);
7821 /* Ordinary template template argument. */
7825 case REINTERPRET_CAST_EXPR:
7826 case CONST_CAST_EXPR:
7827 case STATIC_CAST_EXPR:
7828 case DYNAMIC_CAST_EXPR:
7831 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7832 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7836 case TRUTH_NOT_EXPR:
7839 case UNARY_PLUS_EXPR: /* Unary + */
7848 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7849 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7856 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7857 name = TREE_OPERAND (t, 1);
7858 if (TREE_CODE (name) == BIT_NOT_EXPR)
7860 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7862 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7864 else if (TREE_CODE (name) == SCOPE_REF
7865 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7867 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7869 name = TREE_OPERAND (name, 1);
7870 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7872 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7873 name = build_nt (SCOPE_REF, base, name);
7875 else if (TREE_CODE (name) == BASELINK)
7876 name = tsubst_baselink (name,
7877 non_reference (TREE_TYPE (object)),
7881 name = tsubst_copy (name, args, complain, in_decl);
7882 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7888 case TRUNC_DIV_EXPR:
7890 case FLOOR_DIV_EXPR:
7891 case ROUND_DIV_EXPR:
7892 case EXACT_DIV_EXPR:
7896 case TRUNC_MOD_EXPR:
7897 case FLOOR_MOD_EXPR:
7898 case TRUTH_ANDIF_EXPR:
7899 case TRUTH_ORIF_EXPR:
7900 case TRUTH_AND_EXPR:
7918 case PREDECREMENT_EXPR:
7919 case PREINCREMENT_EXPR:
7920 case POSTDECREMENT_EXPR:
7921 case POSTINCREMENT_EXPR:
7923 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7924 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7929 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7930 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7931 NULL_TREE, NULL_TREE);
7934 return build_nt (code,
7935 tsubst_copy (TREE_OPERAND (t, 0), args,
7937 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7943 case PSEUDO_DTOR_EXPR:
7946 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7947 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7948 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7949 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7956 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7957 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7958 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7959 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7966 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7967 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7968 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7969 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7973 case TEMPLATE_ID_EXPR:
7975 /* Substituted template arguments */
7976 tree fn = TREE_OPERAND (t, 0);
7977 tree targs = TREE_OPERAND (t, 1);
7979 fn = tsubst_copy (fn, args, complain, in_decl);
7981 targs = tsubst_template_args (targs, args, complain, in_decl);
7983 return lookup_template_function (fn, targs);
7988 tree purpose, value, chain;
7990 if (t == void_list_node)
7993 purpose = TREE_PURPOSE (t);
7995 purpose = tsubst_copy (purpose, args, complain, in_decl);
7996 value = TREE_VALUE (t);
7998 value = tsubst_copy (value, args, complain, in_decl);
7999 chain = TREE_CHAIN (t);
8000 if (chain && chain != void_type_node)
8001 chain = tsubst_copy (chain, args, complain, in_decl);
8002 if (purpose == TREE_PURPOSE (t)
8003 && value == TREE_VALUE (t)
8004 && chain == TREE_CHAIN (t))
8006 return tree_cons (purpose, value, chain);
8013 case TEMPLATE_TYPE_PARM:
8014 case TEMPLATE_TEMPLATE_PARM:
8015 case BOUND_TEMPLATE_TEMPLATE_PARM:
8016 case TEMPLATE_PARM_INDEX:
8018 case REFERENCE_TYPE:
8024 case UNBOUND_CLASS_TEMPLATE:
8027 return tsubst (t, args, complain, in_decl);
8029 case IDENTIFIER_NODE:
8030 if (IDENTIFIER_TYPENAME_P (t))
8032 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8033 return mangle_conv_op_name_for_type (new_type);
8039 /* This is handled by tsubst_copy_and_build. */
8043 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8045 tsubst (TREE_TYPE (t), args, complain, in_decl));
8047 case CLEANUP_POINT_EXPR:
8048 /* We shouldn't have built any of these during initial template
8049 generation. Instead, they should be built during instantiation
8050 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8058 /* Like tsubst_copy for expressions, etc. but also does semantic
8062 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8066 if (t == NULL_TREE || t == error_mark_node)
8069 if (EXPR_HAS_LOCATION (t))
8070 input_location = EXPR_LOCATION (t);
8071 if (STATEMENT_CODE_P (TREE_CODE (t)))
8072 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8074 switch (TREE_CODE (t))
8076 case STATEMENT_LIST:
8078 tree_stmt_iterator i;
8079 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8080 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8084 case CTOR_INITIALIZER:
8085 finish_mem_initializers (tsubst_initializer_list
8086 (TREE_OPERAND (t, 0), args));
8090 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8091 args, complain, in_decl));
8095 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8096 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8097 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8099 finish_expr_stmt (tmp);
8103 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8104 args, complain, in_decl));
8112 decl = DECL_EXPR_DECL (t);
8113 if (TREE_CODE (decl) == LABEL_DECL)
8114 finish_label_decl (DECL_NAME (decl));
8115 else if (TREE_CODE (decl) == USING_DECL)
8117 tree scope = USING_DECL_SCOPE (decl);
8118 tree name = DECL_NAME (decl);
8121 scope = tsubst_expr (scope, args, complain, in_decl);
8122 decl = lookup_qualified_name (scope, name,
8123 /*is_type_p=*/false,
8124 /*complain=*/false);
8125 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8126 qualified_name_lookup_error (scope, name, decl);
8128 do_local_using_decl (decl, scope, name);
8132 init = DECL_INITIAL (decl);
8133 decl = tsubst (decl, args, complain, in_decl);
8134 if (decl != error_mark_node)
8137 DECL_INITIAL (decl) = error_mark_node;
8138 /* By marking the declaration as instantiated, we avoid
8139 trying to instantiate it. Since instantiate_decl can't
8140 handle local variables, and since we've already done
8141 all that needs to be done, that's the right thing to
8143 if (TREE_CODE (decl) == VAR_DECL)
8144 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8145 if (TREE_CODE (decl) == VAR_DECL
8146 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8147 /* Anonymous aggregates are a special case. */
8148 finish_anon_union (decl);
8151 maybe_push_decl (decl);
8152 if (TREE_CODE (decl) == VAR_DECL
8153 && DECL_PRETTY_FUNCTION_P (decl))
8155 /* For __PRETTY_FUNCTION__ we have to adjust the
8157 const char *const name
8158 = cxx_printable_name (current_function_decl, 2);
8159 init = cp_fname_init (name, &TREE_TYPE (decl));
8162 init = tsubst_expr (init, args, complain, in_decl);
8163 cp_finish_decl (decl, init, NULL_TREE, 0);
8168 /* A DECL_EXPR can also be used as an expression, in the condition
8169 clause of an if/for/while construct. */
8174 stmt = begin_for_stmt ();
8175 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8176 finish_for_init_stmt (stmt);
8177 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8178 finish_for_cond (tmp, stmt);
8179 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8180 finish_for_expr (tmp, stmt);
8181 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8182 finish_for_stmt (stmt);
8186 stmt = begin_while_stmt ();
8187 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8188 finish_while_stmt_cond (tmp, stmt);
8189 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8190 finish_while_stmt (stmt);
8194 stmt = begin_do_stmt ();
8195 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8196 finish_do_body (stmt);
8197 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8198 finish_do_stmt (tmp, stmt);
8202 stmt = begin_if_stmt ();
8203 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8204 finish_if_stmt_cond (tmp, stmt);
8205 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8206 finish_then_clause (stmt);
8208 if (ELSE_CLAUSE (t))
8210 begin_else_clause (stmt);
8211 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8212 finish_else_clause (stmt);
8215 finish_if_stmt (stmt);
8219 if (BIND_EXPR_BODY_BLOCK (t))
8220 stmt = begin_function_body ();
8222 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8223 ? BCS_TRY_BLOCK : 0);
8225 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8227 if (BIND_EXPR_BODY_BLOCK (t))
8228 finish_function_body (stmt);
8230 finish_compound_stmt (stmt);
8234 finish_break_stmt ();
8238 finish_continue_stmt ();
8242 stmt = begin_switch_stmt ();
8243 tmp = tsubst_expr (SWITCH_STMT_COND (t), args, complain, in_decl);
8244 finish_switch_cond (tmp, stmt);
8245 tsubst_expr (SWITCH_STMT_BODY (t), args, complain, in_decl);
8246 finish_switch_stmt (stmt);
8249 case CASE_LABEL_EXPR:
8250 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8251 tsubst_expr (CASE_HIGH (t), args, complain,
8256 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8260 tmp = GOTO_DESTINATION (t);
8261 if (TREE_CODE (tmp) != LABEL_DECL)
8262 /* Computed goto's must be tsubst'd into. On the other hand,
8263 non-computed gotos must not be; the identifier in question
8264 will have no binding. */
8265 tmp = tsubst_expr (tmp, args, complain, in_decl);
8267 tmp = DECL_NAME (tmp);
8268 finish_goto_stmt (tmp);
8272 tmp = finish_asm_stmt
8273 (ASM_VOLATILE_P (t),
8274 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8275 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8276 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8277 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8279 tree asm_expr = tmp;
8280 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8281 asm_expr = TREE_OPERAND (asm_expr, 0);
8282 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8289 stmt = begin_try_block ();
8290 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8291 finish_cleanup_try_block (stmt);
8292 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8298 if (FN_TRY_BLOCK_P (t))
8299 stmt = begin_function_try_block ();
8301 stmt = begin_try_block ();
8303 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8305 if (FN_TRY_BLOCK_P (t))
8306 finish_function_try_block (stmt);
8308 finish_try_block (stmt);
8310 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8311 if (FN_TRY_BLOCK_P (t))
8312 finish_function_handler_sequence (stmt);
8314 finish_handler_sequence (stmt);
8322 stmt = begin_handler ();
8323 if (HANDLER_PARMS (t))
8325 decl = HANDLER_PARMS (t);
8326 decl = tsubst (decl, args, complain, in_decl);
8327 /* Prevent instantiate_decl from trying to instantiate
8328 this variable. We've already done all that needs to be
8330 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8334 finish_handler_parms (decl, stmt);
8335 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8336 finish_handler (stmt);
8341 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8345 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8347 return tsubst_copy_and_build (t, args, complain, in_decl,
8348 /*function_p=*/false);
8354 /* T is a postfix-expression that is not being used in a function
8355 call. Return the substituted version of T. */
8358 tsubst_non_call_postfix_expression (tree t, tree args,
8359 tsubst_flags_t complain,
8362 if (TREE_CODE (t) == SCOPE_REF)
8363 t = tsubst_qualified_id (t, args, complain, in_decl,
8364 /*done=*/false, /*address_p=*/false);
8366 t = tsubst_copy_and_build (t, args, complain, in_decl,
8367 /*function_p=*/false);
8372 /* Like tsubst but deals with expressions and performs semantic
8373 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8376 tsubst_copy_and_build (tree t,
8378 tsubst_flags_t complain,
8382 #define RECUR(NODE) \
8383 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8387 if (t == NULL_TREE || t == error_mark_node)
8390 switch (TREE_CODE (t))
8395 case IDENTIFIER_NODE:
8399 tree qualifying_class;
8400 bool non_integral_constant_expression_p;
8401 const char *error_msg;
8403 if (IDENTIFIER_TYPENAME_P (t))
8405 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8406 t = mangle_conv_op_name_for_type (new_type);
8409 /* Look up the name. */
8410 decl = lookup_name (t, 0);
8412 /* By convention, expressions use ERROR_MARK_NODE to indicate
8413 failure, not NULL_TREE. */
8414 if (decl == NULL_TREE)
8415 decl = error_mark_node;
8417 decl = finish_id_expression (t, decl, NULL_TREE,
8420 /*integral_constant_expression_p=*/false,
8421 /*allow_non_integral_constant_expression_p=*/false,
8422 &non_integral_constant_expression_p,
8426 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8427 decl = unqualified_name_lookup_error (decl);
8431 case TEMPLATE_ID_EXPR:
8434 tree template = RECUR (TREE_OPERAND (t, 0));
8435 tree targs = TREE_OPERAND (t, 1);
8438 targs = tsubst_template_args (targs, args, complain, in_decl);
8440 if (TREE_CODE (template) == COMPONENT_REF)
8442 object = TREE_OPERAND (template, 0);
8443 template = TREE_OPERAND (template, 1);
8447 template = lookup_template_function (template, targs);
8450 return build3 (COMPONENT_REF, TREE_TYPE (template),
8451 object, template, NULL_TREE);
8458 tree r = RECUR (TREE_OPERAND (t, 0));
8460 if (REFERENCE_REF_P (t))
8462 /* A type conversion to reference type will be enclosed in
8463 such an indirect ref, but the substitution of the cast
8464 will have also added such an indirect ref. */
8465 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8466 r = convert_from_reference (r);
8469 r = build_x_indirect_ref (r, "unary *");
8475 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8476 RECUR (TREE_OPERAND (t, 0)));
8479 return build_functional_cast
8480 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8481 RECUR (TREE_OPERAND (t, 0)));
8483 case REINTERPRET_CAST_EXPR:
8484 return build_reinterpret_cast
8485 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8486 RECUR (TREE_OPERAND (t, 0)));
8488 case CONST_CAST_EXPR:
8489 return build_const_cast
8490 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8491 RECUR (TREE_OPERAND (t, 0)));
8493 case DYNAMIC_CAST_EXPR:
8494 return build_dynamic_cast
8495 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8496 RECUR (TREE_OPERAND (t, 0)));
8498 case STATIC_CAST_EXPR:
8499 return build_static_cast
8500 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8501 RECUR (TREE_OPERAND (t, 0)));
8503 case POSTDECREMENT_EXPR:
8504 case POSTINCREMENT_EXPR:
8505 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8506 args, complain, in_decl);
8507 return build_x_unary_op (TREE_CODE (t), op1);
8509 case PREDECREMENT_EXPR:
8510 case PREINCREMENT_EXPR:
8514 case TRUTH_NOT_EXPR:
8515 case UNARY_PLUS_EXPR: /* Unary + */
8518 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8521 op1 = TREE_OPERAND (t, 0);
8522 if (TREE_CODE (op1) == SCOPE_REF)
8523 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8524 /*done=*/true, /*address_p=*/true);
8526 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8528 if (TREE_CODE (op1) == LABEL_DECL)
8529 return finish_label_address_expr (DECL_NAME (op1));
8530 return build_x_unary_op (ADDR_EXPR, op1);
8535 case TRUNC_DIV_EXPR:
8537 case FLOOR_DIV_EXPR:
8538 case ROUND_DIV_EXPR:
8539 case EXACT_DIV_EXPR:
8543 case TRUNC_MOD_EXPR:
8544 case FLOOR_MOD_EXPR:
8545 case TRUTH_ANDIF_EXPR:
8546 case TRUTH_ORIF_EXPR:
8547 case TRUTH_AND_EXPR:
8563 return build_x_binary_op
8565 RECUR (TREE_OPERAND (t, 0)),
8566 RECUR (TREE_OPERAND (t, 1)),
8567 /*overloaded_p=*/NULL);
8570 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8571 /*address_p=*/false);
8573 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8574 args, complain, in_decl);
8575 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8576 /*overloaded_p=*/NULL);
8580 op1 = TREE_OPERAND (t, 0);
8583 /* When there are no ARGS, we are trying to evaluate a
8584 non-dependent expression from the parser. Trying to do
8585 the substitutions may not work. */
8587 op1 = TREE_TYPE (op1);
8596 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8598 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8602 tree r = build_x_modify_expr
8603 (RECUR (TREE_OPERAND (t, 0)),
8604 TREE_CODE (TREE_OPERAND (t, 1)),
8605 RECUR (TREE_OPERAND (t, 2)));
8606 /* TREE_NO_WARNING must be set if either the expression was
8607 parenthesized or it uses an operator such as >>= rather
8608 than plain assignment. In the former case, it was already
8609 set and must be copied. In the latter case,
8610 build_x_modify_expr sets it and it must not be reset
8612 if (TREE_NO_WARNING (t))
8613 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8618 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8619 args, complain, in_decl);
8620 /* Remember that there was a reference to this entity. */
8623 return build_x_arrow (op1);
8627 (RECUR (TREE_OPERAND (t, 0)),
8628 RECUR (TREE_OPERAND (t, 1)),
8629 RECUR (TREE_OPERAND (t, 2)),
8630 RECUR (TREE_OPERAND (t, 3)),
8631 NEW_EXPR_USE_GLOBAL (t));
8634 return delete_sanity
8635 (RECUR (TREE_OPERAND (t, 0)),
8636 RECUR (TREE_OPERAND (t, 1)),
8637 DELETE_EXPR_USE_VEC (t),
8638 DELETE_EXPR_USE_GLOBAL (t));
8641 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8642 RECUR (TREE_OPERAND (t, 1)));
8651 function = TREE_OPERAND (t, 0);
8652 /* When we parsed the expression, we determined whether or
8653 not Koenig lookup should be performed. */
8654 koenig_p = KOENIG_LOOKUP_P (t);
8655 if (TREE_CODE (function) == SCOPE_REF)
8658 function = tsubst_qualified_id (function, args, complain, in_decl,
8660 /*address_p=*/false);
8664 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8665 && (TREE_CODE (TREE_OPERAND (function, 1))
8667 function = tsubst_copy_and_build (function, args, complain,
8670 if (BASELINK_P (function))
8674 call_args = RECUR (TREE_OPERAND (t, 1));
8676 /* We do not perform argument-dependent lookup if normal
8677 lookup finds a non-function, in accordance with the
8678 expected resolution of DR 218. */
8680 && ((is_overloaded_fn (function)
8681 /* If lookup found a member function, the Koenig lookup is
8682 not appropriate, even if an unqualified-name was used
8683 to denote the function. */
8684 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8685 || TREE_CODE (function) == IDENTIFIER_NODE))
8686 function = perform_koenig_lookup (function, call_args);
8688 if (TREE_CODE (function) == IDENTIFIER_NODE)
8690 unqualified_name_lookup_error (function);
8691 return error_mark_node;
8694 /* Remember that there was a reference to this entity. */
8695 if (DECL_P (function))
8696 mark_used (function);
8698 if (TREE_CODE (function) == OFFSET_REF)
8699 return build_offset_ref_call_from_tree (function, call_args);
8700 if (TREE_CODE (function) == COMPONENT_REF)
8702 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8703 return finish_call_expr (function, call_args,
8704 /*disallow_virtual=*/false,
8705 /*koenig_p=*/false);
8707 return (build_new_method_call
8708 (TREE_OPERAND (function, 0),
8709 TREE_OPERAND (function, 1),
8710 call_args, NULL_TREE,
8711 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8713 return finish_call_expr (function, call_args,
8714 /*disallow_virtual=*/qualified_p,
8719 return build_x_conditional_expr
8720 (RECUR (TREE_OPERAND (t, 0)),
8721 RECUR (TREE_OPERAND (t, 1)),
8722 RECUR (TREE_OPERAND (t, 2)));
8724 case PSEUDO_DTOR_EXPR:
8725 return finish_pseudo_destructor_expr
8726 (RECUR (TREE_OPERAND (t, 0)),
8727 RECUR (TREE_OPERAND (t, 1)),
8728 RECUR (TREE_OPERAND (t, 2)));
8732 tree purpose, value, chain;
8734 if (t == void_list_node)
8737 purpose = TREE_PURPOSE (t);
8739 purpose = RECUR (purpose);
8740 value = TREE_VALUE (t);
8742 value = RECUR (value);
8743 chain = TREE_CHAIN (t);
8744 if (chain && chain != void_type_node)
8745 chain = RECUR (chain);
8746 if (purpose == TREE_PURPOSE (t)
8747 && value == TREE_VALUE (t)
8748 && chain == TREE_CHAIN (t))
8750 return tree_cons (purpose, value, chain);
8758 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8759 args, complain, in_decl);
8760 /* Remember that there was a reference to this entity. */
8761 if (DECL_P (object))
8764 member = TREE_OPERAND (t, 1);
8765 if (BASELINK_P (member))
8766 member = tsubst_baselink (member,
8767 non_reference (TREE_TYPE (object)),
8768 args, complain, in_decl);
8770 member = tsubst_copy (member, args, complain, in_decl);
8772 if (member == error_mark_node)
8773 return error_mark_node;
8774 else if (!CLASS_TYPE_P (TREE_TYPE (object)))
8776 if (TREE_CODE (member) == BIT_NOT_EXPR)
8777 return finish_pseudo_destructor_expr (object,
8779 TREE_TYPE (object));
8780 else if (TREE_CODE (member) == SCOPE_REF
8781 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8782 return finish_pseudo_destructor_expr (object,
8784 TREE_TYPE (object));
8786 else if (TREE_CODE (member) == SCOPE_REF
8787 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8792 /* Lookup the template functions now that we know what the
8794 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8795 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8796 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8797 /*is_type_p=*/false,
8798 /*complain=*/false);
8799 if (BASELINK_P (member))
8801 BASELINK_FUNCTIONS (member)
8802 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8804 member = (adjust_result_of_qualified_name_lookup
8805 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8806 TREE_TYPE (object)));
8810 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8812 return error_mark_node;
8815 else if (TREE_CODE (member) == SCOPE_REF
8816 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8817 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8819 if (complain & tf_error)
8821 if (TYPE_P (TREE_OPERAND (member, 0)))
8822 error ("%qT is not a class or namespace",
8823 TREE_OPERAND (member, 0));
8825 error ("%qD is not a class or namespace",
8826 TREE_OPERAND (member, 0));
8828 return error_mark_node;
8830 else if (TREE_CODE (member) == FIELD_DECL)
8831 return finish_non_static_data_member (member, object, NULL_TREE);
8833 return finish_class_member_access_expr (object, member);
8838 (RECUR (TREE_OPERAND (t, 0)));
8842 VEC(constructor_elt,gc) *n;
8843 constructor_elt *ce;
8844 unsigned HOST_WIDE_INT idx;
8846 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8847 bool process_index_p;
8849 /* digest_init will do the wrong thing if we let it. */
8850 if (type && TYPE_PTRMEMFUNC_P (type))
8853 /* We do not want to process the index of aggregate
8854 initializers as they are identifier nodes which will be
8855 looked up by digest_init. */
8856 process_index_p = !(type && IS_AGGR_TYPE (type));
8858 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
8859 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
8861 if (ce->index && process_index_p)
8862 ce->index = RECUR (ce->index);
8863 ce->value = RECUR (ce->value);
8866 r = build_constructor (NULL_TREE, n);
8867 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8870 return digest_init (type, r);
8876 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8877 if (TYPE_P (operand_0))
8878 return get_typeid (operand_0);
8879 return build_typeid (operand_0);
8889 tree r = tsubst_copy (t, args, complain, in_decl);
8891 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
8892 /* If the original type was a reference, we'll be wrapped in
8893 the appropriate INDIRECT_REF. */
8894 r = convert_from_reference (r);
8899 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8900 tsubst_copy (TREE_TYPE (t), args, complain,
8904 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8908 tree old_stmt_expr = cur_stmt_expr;
8909 tree stmt_expr = begin_stmt_expr ();
8911 cur_stmt_expr = stmt_expr;
8912 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8913 stmt_expr = finish_stmt_expr (stmt_expr, false);
8914 cur_stmt_expr = old_stmt_expr;
8920 t = tsubst_copy (t, args, complain, in_decl);
8921 /* As in finish_id_expression, we resolve enumeration constants
8922 to their underlying values. */
8923 if (TREE_CODE (t) == CONST_DECL)
8924 return DECL_INITIAL (t);
8928 /* Handle Objective-C++ constructs, if appropriate. */
8931 = objcp_tsubst_copy_and_build (t, args, complain,
8932 in_decl, /*function_p=*/false);
8936 return tsubst_copy (t, args, complain, in_decl);
8942 /* Verify that the instantiated ARGS are valid. For type arguments,
8943 make sure that the type's linkage is ok. For non-type arguments,
8944 make sure they are constants if they are integral or enumerations.
8945 Emit an error under control of COMPLAIN, and return TRUE on error. */
8948 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8950 int ix, len = DECL_NTPARMS (tmpl);
8951 bool result = false;
8952 bool error_p = complain & tf_error;
8954 for (ix = 0; ix != len; ix++)
8956 tree t = TREE_VEC_ELT (args, ix);
8960 /* [basic.link]: A name with no linkage (notably, the name
8961 of a class or enumeration declared in a local scope)
8962 shall not be used to declare an entity with linkage.
8963 This implies that names with no linkage cannot be used as
8964 template arguments. */
8965 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8969 if (TYPE_ANONYMOUS_P (nt))
8970 error ("%qT is/uses anonymous type", t);
8972 error ("%qT uses local type %qT", t, nt);
8976 /* In order to avoid all sorts of complications, we do not
8977 allow variably-modified types as template arguments. */
8978 else if (variably_modified_type_p (t, NULL_TREE))
8980 if (complain & tf_error)
8981 error ("%qT is a variably modified type", t);
8985 /* A non-type argument of integral or enumerated type must be a
8987 else if (TREE_TYPE (t)
8988 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8989 && !TREE_CONSTANT (t))
8991 if (complain & tf_error)
8992 error ("integral expression %qE is not constant", t);
8996 if (result && error_p)
8997 error (" trying to instantiate %qD", tmpl);
9001 /* Instantiate the indicated variable or function template TMPL with
9002 the template arguments in TARG_PTR. */
9005 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
9011 if (tmpl == error_mark_node)
9012 return error_mark_node;
9014 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
9016 /* If this function is a clone, handle it specially. */
9017 if (DECL_CLONED_FUNCTION_P (tmpl))
9022 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
9024 if (spec == error_mark_node)
9025 return error_mark_node;
9027 /* Look for the clone. */
9028 FOR_EACH_CLONE (clone, spec)
9029 if (DECL_NAME (clone) == DECL_NAME (tmpl))
9031 /* We should always have found the clone by now. */
9036 /* Check to see if we already have this specialization. */
9037 spec = retrieve_specialization (tmpl, targ_ptr,
9038 /*class_specializations_p=*/false);
9039 if (spec != NULL_TREE)
9042 gen_tmpl = most_general_template (tmpl);
9043 if (tmpl != gen_tmpl)
9045 /* The TMPL is a partial instantiation. To get a full set of
9046 arguments we must add the arguments used to perform the
9047 partial instantiation. */
9048 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9051 /* Check to see if we already have this specialization. */
9052 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9053 /*class_specializations_p=*/false);
9054 if (spec != NULL_TREE)
9058 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9060 return error_mark_node;
9062 /* We are building a FUNCTION_DECL, during which the access of its
9063 parameters and return types have to be checked. However this
9064 FUNCTION_DECL which is the desired context for access checking
9065 is not built yet. We solve this chicken-and-egg problem by
9066 deferring all checks until we have the FUNCTION_DECL. */
9067 push_deferring_access_checks (dk_deferred);
9069 /* Substitute template parameters. */
9070 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9071 targ_ptr, complain, gen_tmpl);
9073 /* Now we know the specialization, compute access previously
9075 push_access_scope (fndecl);
9076 perform_deferred_access_checks ();
9077 pop_access_scope (fndecl);
9078 pop_deferring_access_checks ();
9080 /* The DECL_TI_TEMPLATE should always be the immediate parent
9081 template, not the most general template. */
9082 DECL_TI_TEMPLATE (fndecl) = tmpl;
9084 /* If we've just instantiated the main entry point for a function,
9085 instantiate all the alternate entry points as well. We do this
9086 by cloning the instantiation of the main entry point, not by
9087 instantiating the template clones. */
9088 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9089 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9094 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9095 arguments that are being used when calling it. TARGS is a vector
9096 into which the deduced template arguments are placed.
9098 Return zero for success, 2 for an incomplete match that doesn't resolve
9099 all the types, and 1 for complete failure. An error message will be
9100 printed only for an incomplete match.
9102 If FN is a conversion operator, or we are trying to produce a specific
9103 specialization, RETURN_TYPE is the return type desired.
9105 The EXPLICIT_TARGS are explicit template arguments provided via a
9108 The parameter STRICT is one of:
9111 We are deducing arguments for a function call, as in
9115 We are deducing arguments for a conversion function, as in
9119 We are deducing arguments when doing an explicit instantiation
9120 as in [temp.explicit], when determining an explicit specialization
9121 as in [temp.expl.spec], or when taking the address of a function
9122 template, as in [temp.deduct.funcaddr]. */
9125 fn_type_unification (tree fn,
9126 tree explicit_targs,
9130 unification_kind_t strict,
9137 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9139 fntype = TREE_TYPE (fn);
9144 The specified template arguments must match the template
9145 parameters in kind (i.e., type, nontype, template), and there
9146 must not be more arguments than there are parameters;
9147 otherwise type deduction fails.
9149 Nontype arguments must match the types of the corresponding
9150 nontype template parameters, or must be convertible to the
9151 types of the corresponding nontype parameters as specified in
9152 _temp.arg.nontype_, otherwise type deduction fails.
9154 All references in the function type of the function template
9155 to the corresponding template parameters are replaced by the
9156 specified template argument values. If a substitution in a
9157 template parameter or in the function type of the function
9158 template results in an invalid type, type deduction fails. */
9160 tree converted_args;
9163 if (explicit_targs == error_mark_node)
9167 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9168 explicit_targs, NULL_TREE, tf_none,
9169 /*require_all_arguments=*/0));
9170 if (converted_args == error_mark_node)
9173 /* Substitute the explicit args into the function type. This is
9174 necessary so that, for instance, explicitly declared function
9175 arguments can match null pointed constants. If we were given
9176 an incomplete set of explicit args, we must not do semantic
9177 processing during substitution as we could create partial
9179 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9180 processing_template_decl += incomplete;
9181 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9182 processing_template_decl -= incomplete;
9184 if (fntype == error_mark_node)
9187 /* Place the explicitly specified arguments in TARGS. */
9188 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9189 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9192 parms = TYPE_ARG_TYPES (fntype);
9193 /* Never do unification on the 'this' parameter. */
9194 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9195 parms = TREE_CHAIN (parms);
9199 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9200 args = tree_cons (NULL_TREE, return_type, args);
9203 /* We allow incomplete unification without an error message here
9204 because the standard doesn't seem to explicitly prohibit it. Our
9205 callers must be ready to deal with unification failures in any
9207 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9208 targs, parms, args, /*subr=*/0,
9212 /* All is well so far. Now, check:
9216 When all template arguments have been deduced, all uses of
9217 template parameters in nondeduced contexts are replaced with
9218 the corresponding deduced argument values. If the
9219 substitution results in an invalid type, as described above,
9220 type deduction fails. */
9221 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9228 /* Adjust types before performing type deduction, as described in
9229 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9230 sections are symmetric. PARM is the type of a function parameter
9231 or the return type of the conversion function. ARG is the type of
9232 the argument passed to the call, or the type of the value
9233 initialized with the result of the conversion function. */
9236 maybe_adjust_types_for_deduction (unification_kind_t strict,
9249 /* Swap PARM and ARG throughout the remainder of this
9250 function; the handling is precisely symmetric since PARM
9251 will initialize ARG rather than vice versa. */
9259 /* There is nothing to do in this case. */
9266 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9268 /* [temp.deduct.call]
9270 If P is not a reference type:
9272 --If A is an array type, the pointer type produced by the
9273 array-to-pointer standard conversion (_conv.array_) is
9274 used in place of A for type deduction; otherwise,
9276 --If A is a function type, the pointer type produced by
9277 the function-to-pointer standard conversion
9278 (_conv.func_) is used in place of A for type deduction;
9281 --If A is a cv-qualified type, the top level
9282 cv-qualifiers of A's type are ignored for type
9284 if (TREE_CODE (*arg) == ARRAY_TYPE)
9285 *arg = build_pointer_type (TREE_TYPE (*arg));
9286 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9287 *arg = build_pointer_type (*arg);
9289 *arg = TYPE_MAIN_VARIANT (*arg);
9292 /* [temp.deduct.call]
9294 If P is a cv-qualified type, the top level cv-qualifiers
9295 of P's type are ignored for type deduction. If P is a
9296 reference type, the type referred to by P is used for
9298 *parm = TYPE_MAIN_VARIANT (*parm);
9299 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9301 *parm = TREE_TYPE (*parm);
9302 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9305 /* DR 322. For conversion deduction, remove a reference type on parm
9306 too (which has been swapped into ARG). */
9307 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9308 *arg = TREE_TYPE (*arg);
9313 /* Most parms like fn_type_unification.
9315 If SUBR is 1, we're being called recursively (to unify the
9316 arguments of a function or method parameter of a function
9320 type_unification_real (tree tparms,
9325 unification_kind_t strict,
9330 int ntparms = TREE_VEC_LENGTH (tparms);
9332 int saw_undeduced = 0;
9335 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9336 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9337 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9338 gcc_assert (ntparms > 0);
9343 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9344 | UNIFY_ALLOW_DERIVED);
9348 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9352 sub_strict = UNIFY_ALLOW_NONE;
9363 while (parms && parms != void_list_node
9364 && args && args != void_list_node)
9366 parm = TREE_VALUE (parms);
9367 parms = TREE_CHAIN (parms);
9368 arg = TREE_VALUE (args);
9369 args = TREE_CHAIN (args);
9371 if (arg == error_mark_node)
9373 if (arg == unknown_type_node)
9374 /* We can't deduce anything from this, but we might get all the
9375 template args from other function args. */
9378 /* Conversions will be performed on a function argument that
9379 corresponds with a function parameter that contains only
9380 non-deducible template parameters and explicitly specified
9381 template parameters. */
9382 if (!uses_template_parms (parm))
9387 type = TREE_TYPE (arg);
9391 if (same_type_p (parm, type))
9393 if (strict != DEDUCE_EXACT
9394 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
9403 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9404 if (type_unknown_p (arg))
9406 /* [temp.deduct.type] A template-argument can be deduced from
9407 a pointer to function or pointer to member function
9408 argument if the set of overloaded functions does not
9409 contain function templates and at most one of a set of
9410 overloaded functions provides a unique match. */
9412 if (resolve_overloaded_unification
9413 (tparms, targs, parm, arg, strict, sub_strict)
9418 arg = TREE_TYPE (arg);
9419 if (arg == error_mark_node)
9424 int arg_strict = sub_strict;
9427 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9429 if (unify (tparms, targs, parm, arg, arg_strict))
9434 /* Fail if we've reached the end of the parm list, and more args
9435 are present, and the parm list isn't variadic. */
9436 if (args && args != void_list_node && parms == void_list_node)
9438 /* Fail if parms are left and they don't have default values. */
9439 if (parms && parms != void_list_node
9440 && TREE_PURPOSE (parms) == NULL_TREE)
9444 for (i = 0; i < ntparms; i++)
9445 if (!TREE_VEC_ELT (targs, i))
9447 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9449 /* If this is an undeduced nontype parameter that depends on
9450 a type parameter, try another pass; its type may have been
9451 deduced from a later argument than the one from which
9452 this parameter can be deduced. */
9453 if (TREE_CODE (tparm) == PARM_DECL
9454 && uses_template_parms (TREE_TYPE (tparm))
9455 && !saw_undeduced++)
9464 /* Subroutine of type_unification_real. Args are like the variables at the
9465 call site. ARG is an overloaded function (or template-id); we try
9466 deducing template args from each of the overloads, and if only one
9467 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9470 resolve_overloaded_unification (tree tparms,
9474 unification_kind_t strict,
9477 tree tempargs = copy_node (targs);
9481 if (TREE_CODE (arg) == ADDR_EXPR)
9483 arg = TREE_OPERAND (arg, 0);
9489 if (TREE_CODE (arg) == COMPONENT_REF)
9490 /* Handle `&x' where `x' is some static or non-static member
9492 arg = TREE_OPERAND (arg, 1);
9494 if (TREE_CODE (arg) == OFFSET_REF)
9495 arg = TREE_OPERAND (arg, 1);
9497 /* Strip baselink information. */
9498 if (BASELINK_P (arg))
9499 arg = BASELINK_FUNCTIONS (arg);
9501 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9503 /* If we got some explicit template args, we need to plug them into
9504 the affected templates before we try to unify, in case the
9505 explicit args will completely resolve the templates in question. */
9507 tree expl_subargs = TREE_OPERAND (arg, 1);
9508 arg = TREE_OPERAND (arg, 0);
9510 for (; arg; arg = OVL_NEXT (arg))
9512 tree fn = OVL_CURRENT (arg);
9515 if (TREE_CODE (fn) != TEMPLATE_DECL)
9518 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
9519 expl_subargs, /*check_ret=*/false);
9522 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9523 good += try_one_overload (tparms, targs, tempargs, parm,
9524 elem, strict, sub_strict, addr_p);
9530 gcc_assert (TREE_CODE (arg) == OVERLOAD
9531 || TREE_CODE (arg) == FUNCTION_DECL);
9533 for (; arg; arg = OVL_NEXT (arg))
9534 good += try_one_overload (tparms, targs, tempargs, parm,
9535 TREE_TYPE (OVL_CURRENT (arg)),
9536 strict, sub_strict, addr_p);
9539 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9540 to function or pointer to member function argument if the set of
9541 overloaded functions does not contain function templates and at most
9542 one of a set of overloaded functions provides a unique match.
9544 So if we found multiple possibilities, we return success but don't
9549 int i = TREE_VEC_LENGTH (targs);
9551 if (TREE_VEC_ELT (tempargs, i))
9552 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9560 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9561 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9562 different overloads deduce different arguments for a given parm.
9563 ADDR_P is true if the expression for which deduction is being
9564 performed was of the form "& fn" rather than simply "fn".
9566 Returns 1 on success. */
9569 try_one_overload (tree tparms,
9574 unification_kind_t strict,
9582 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9583 to function or pointer to member function argument if the set of
9584 overloaded functions does not contain function templates and at most
9585 one of a set of overloaded functions provides a unique match.
9587 So if this is a template, just return success. */
9589 if (uses_template_parms (arg))
9592 if (TREE_CODE (arg) == METHOD_TYPE)
9593 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9595 arg = build_pointer_type (arg);
9597 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9599 /* We don't copy orig_targs for this because if we have already deduced
9600 some template args from previous args, unify would complain when we
9601 try to deduce a template parameter for the same argument, even though
9602 there isn't really a conflict. */
9603 nargs = TREE_VEC_LENGTH (targs);
9604 tempargs = make_tree_vec (nargs);
9606 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9609 /* First make sure we didn't deduce anything that conflicts with
9610 explicitly specified args. */
9611 for (i = nargs; i--; )
9613 tree elt = TREE_VEC_ELT (tempargs, i);
9614 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9618 else if (uses_template_parms (elt))
9619 /* Since we're unifying against ourselves, we will fill in
9620 template args used in the function parm list with our own
9621 template parms. Discard them. */
9622 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9623 else if (oldelt && !template_args_equal (oldelt, elt))
9627 for (i = nargs; i--; )
9629 tree elt = TREE_VEC_ELT (tempargs, i);
9632 TREE_VEC_ELT (targs, i) = elt;
9638 /* Verify that nondeduce template argument agrees with the type
9639 obtained from argument deduction. Return nonzero if the
9644 struct A { typedef int X; };
9645 template <class T, class U> struct C {};
9646 template <class T> struct C<T, typename T::X> {};
9648 Then with the instantiation `C<A, int>', we can deduce that
9649 `T' is `A' but unify () does not check whether `typename T::X'
9650 is `int'. This function ensure that they agree.
9652 TARGS, PARMS are the same as the arguments of unify.
9653 ARGS contains template arguments from all levels. */
9656 verify_class_unification (tree targs, tree parms, tree args)
9658 parms = tsubst (parms, add_outermost_template_args (args, targs),
9659 tf_none, NULL_TREE);
9660 if (parms == error_mark_node)
9663 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9666 /* PARM is a template class (perhaps with unbound template
9667 parameters). ARG is a fully instantiated type. If ARG can be
9668 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9669 TARGS are as for unify. */
9672 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9676 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9677 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9678 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9681 /* We need to make a new template argument vector for the call to
9682 unify. If we used TARGS, we'd clutter it up with the result of
9683 the attempted unification, even if this class didn't work out.
9684 We also don't want to commit ourselves to all the unifications
9685 we've already done, since unification is supposed to be done on
9686 an argument-by-argument basis. In other words, consider the
9687 following pathological case:
9689 template <int I, int J, int K>
9692 template <int I, int J>
9693 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9695 template <int I, int J, int K>
9696 void f(S<I, J, K>, S<I, I, I>);
9705 Now, by the time we consider the unification involving `s2', we
9706 already know that we must have `f<0, 0, 0>'. But, even though
9707 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9708 because there are two ways to unify base classes of S<0, 1, 2>
9709 with S<I, I, I>. If we kept the already deduced knowledge, we
9710 would reject the possibility I=1. */
9711 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9713 /* If unification failed, we're done. */
9714 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9715 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9721 /* Given a template type PARM and a class type ARG, find the unique
9722 base type in ARG that is an instance of PARM. We do not examine
9723 ARG itself; only its base-classes. If there is not exactly one
9724 appropriate base class, return NULL_TREE. PARM may be the type of
9725 a partial specialization, as well as a plain template type. Used
9729 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9731 tree rval = NULL_TREE;
9734 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9736 binfo = TYPE_BINFO (complete_type (arg));
9738 /* The type could not be completed. */
9741 /* Walk in inheritance graph order. The search order is not
9742 important, and this avoids multiple walks of virtual bases. */
9743 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9745 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9749 /* If there is more than one satisfactory baseclass, then:
9753 If they yield more than one possible deduced A, the type
9757 if (rval && !same_type_p (r, rval))
9767 /* Returns the level of DECL, which declares a template parameter. */
9770 template_decl_level (tree decl)
9772 switch (TREE_CODE (decl))
9776 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9779 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9787 /* Decide whether ARG can be unified with PARM, considering only the
9788 cv-qualifiers of each type, given STRICT as documented for unify.
9789 Returns nonzero iff the unification is OK on that basis. */
9792 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9794 int arg_quals = cp_type_quals (arg);
9795 int parm_quals = cp_type_quals (parm);
9797 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9798 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9800 /* Although a CVR qualifier is ignored when being applied to a
9801 substituted template parameter ([8.3.2]/1 for example), that
9802 does not apply during deduction [14.8.2.4]/1, (even though
9803 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9804 this). Except when we're allowing additional CV qualifiers
9805 at the outer level [14.8.2.1]/3,1st bullet. */
9806 if ((TREE_CODE (arg) == REFERENCE_TYPE
9807 || TREE_CODE (arg) == FUNCTION_TYPE
9808 || TREE_CODE (arg) == METHOD_TYPE)
9809 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9812 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9813 && (parm_quals & TYPE_QUAL_RESTRICT))
9817 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9818 && (arg_quals & parm_quals) != parm_quals)
9821 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9822 && (parm_quals & arg_quals) != arg_quals)
9828 /* Takes parameters as for type_unification. Returns 0 if the
9829 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9830 bitwise or of the following flags:
9833 Require an exact match between PARM and ARG.
9834 UNIFY_ALLOW_MORE_CV_QUAL:
9835 Allow the deduced ARG to be more cv-qualified (by qualification
9836 conversion) than ARG.
9837 UNIFY_ALLOW_LESS_CV_QUAL:
9838 Allow the deduced ARG to be less cv-qualified than ARG.
9839 UNIFY_ALLOW_DERIVED:
9840 Allow the deduced ARG to be a template base class of ARG,
9841 or a pointer to a template base class of the type pointed to by
9843 UNIFY_ALLOW_INTEGER:
9844 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9845 case for more information.
9846 UNIFY_ALLOW_OUTER_LEVEL:
9847 This is the outermost level of a deduction. Used to determine validity
9848 of qualification conversions. A valid qualification conversion must
9849 have const qualified pointers leading up to the inner type which
9850 requires additional CV quals, except at the outer level, where const
9851 is not required [conv.qual]. It would be normal to set this flag in
9852 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9853 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9854 This is the outermost level of a deduction, and PARM can be more CV
9855 qualified at this point.
9856 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9857 This is the outermost level of a deduction, and PARM can be less CV
9858 qualified at this point. */
9861 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9866 int strict_in = strict;
9868 /* I don't think this will do the right thing with respect to types.
9869 But the only case I've seen it in so far has been array bounds, where
9870 signedness is the only information lost, and I think that will be
9872 while (TREE_CODE (parm) == NOP_EXPR)
9873 parm = TREE_OPERAND (parm, 0);
9875 if (arg == error_mark_node)
9877 if (arg == unknown_type_node)
9878 /* We can't deduce anything from this, but we might get all the
9879 template args from other function args. */
9882 /* If PARM uses template parameters, then we can't bail out here,
9883 even if ARG == PARM, since we won't record unifications for the
9884 template parameters. We might need them if we're trying to
9885 figure out which of two things is more specialized. */
9886 if (arg == parm && !uses_template_parms (parm))
9889 /* Immediately reject some pairs that won't unify because of
9890 cv-qualification mismatches. */
9891 if (TREE_CODE (arg) == TREE_CODE (parm)
9893 /* It is the elements of the array which hold the cv quals of an array
9894 type, and the elements might be template type parms. We'll check
9896 && TREE_CODE (arg) != ARRAY_TYPE
9897 /* We check the cv-qualifiers when unifying with template type
9898 parameters below. We want to allow ARG `const T' to unify with
9899 PARM `T' for example, when computing which of two templates
9900 is more specialized, for example. */
9901 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9902 && !check_cv_quals_for_unify (strict_in, arg, parm))
9905 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9906 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9907 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9908 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9909 strict &= ~UNIFY_ALLOW_DERIVED;
9910 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9911 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9913 switch (TREE_CODE (parm))
9917 case UNBOUND_CLASS_TEMPLATE:
9918 /* In a type which contains a nested-name-specifier, template
9919 argument values cannot be deduced for template parameters used
9920 within the nested-name-specifier. */
9923 case TEMPLATE_TYPE_PARM:
9924 case TEMPLATE_TEMPLATE_PARM:
9925 case BOUND_TEMPLATE_TEMPLATE_PARM:
9926 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9928 if (TEMPLATE_TYPE_LEVEL (parm)
9929 != template_decl_level (tparm))
9930 /* The PARM is not one we're trying to unify. Just check
9931 to see if it matches ARG. */
9932 return (TREE_CODE (arg) == TREE_CODE (parm)
9933 && same_type_p (parm, arg)) ? 0 : 1;
9934 idx = TEMPLATE_TYPE_IDX (parm);
9935 targ = TREE_VEC_ELT (targs, idx);
9936 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9938 /* Check for mixed types and values. */
9939 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9940 && TREE_CODE (tparm) != TYPE_DECL)
9941 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9942 && TREE_CODE (tparm) != TEMPLATE_DECL))
9945 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9947 /* ARG must be constructed from a template class or a template
9948 template parameter. */
9949 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9950 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9954 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9955 tree parmvec = TYPE_TI_ARGS (parm);
9956 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9958 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9961 /* The parameter and argument roles have to be switched here
9962 in order to handle default arguments properly. For example,
9963 template<template <class> class TT> void f(TT<int>)
9964 should be able to accept vector<int> which comes from
9965 template <class T, class Allocator = allocator>
9968 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9972 /* Deduce arguments T, i from TT<T> or TT<i>.
9973 We check each element of PARMVEC and ARGVEC individually
9974 rather than the whole TREE_VEC since they can have
9975 different number of elements. */
9977 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9979 if (unify (tparms, targs,
9980 TREE_VEC_ELT (parmvec, i),
9981 TREE_VEC_ELT (argvec, i),
9986 arg = TYPE_TI_TEMPLATE (arg);
9988 /* Fall through to deduce template name. */
9991 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9992 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9994 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9996 /* Simple cases: Value already set, does match or doesn't. */
9997 if (targ != NULL_TREE && template_args_equal (targ, arg))
10004 /* If PARM is `const T' and ARG is only `int', we don't have
10005 a match unless we are allowing additional qualification.
10006 If ARG is `const int' and PARM is just `T' that's OK;
10007 that binds `const int' to `T'. */
10008 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10012 /* Consider the case where ARG is `const volatile int' and
10013 PARM is `const T'. Then, T should be `volatile int'. */
10014 arg = cp_build_qualified_type_real
10015 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10016 if (arg == error_mark_node)
10019 /* Simple cases: Value already set, does match or doesn't. */
10020 if (targ != NULL_TREE && same_type_p (targ, arg))
10025 /* Make sure that ARG is not a variable-sized array. (Note
10026 that were talking about variable-sized arrays (like
10027 `int[n]'), rather than arrays of unknown size (like
10028 `int[]').) We'll get very confused by such a type since
10029 the bound of the array will not be computable in an
10030 instantiation. Besides, such types are not allowed in
10031 ISO C++, so we can do as we please here. */
10032 if (variably_modified_type_p (arg, NULL_TREE))
10036 TREE_VEC_ELT (targs, idx) = arg;
10039 case TEMPLATE_PARM_INDEX:
10040 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10042 if (TEMPLATE_PARM_LEVEL (parm)
10043 != template_decl_level (tparm))
10044 /* The PARM is not one we're trying to unify. Just check
10045 to see if it matches ARG. */
10046 return !(TREE_CODE (arg) == TREE_CODE (parm)
10047 && cp_tree_equal (parm, arg));
10049 idx = TEMPLATE_PARM_IDX (parm);
10050 targ = TREE_VEC_ELT (targs, idx);
10053 return !cp_tree_equal (targ, arg);
10055 /* [temp.deduct.type] If, in the declaration of a function template
10056 with a non-type template-parameter, the non-type
10057 template-parameter is used in an expression in the function
10058 parameter-list and, if the corresponding template-argument is
10059 deduced, the template-argument type shall match the type of the
10060 template-parameter exactly, except that a template-argument
10061 deduced from an array bound may be of any integral type.
10062 The non-type parameter might use already deduced type parameters. */
10063 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10064 if (!TREE_TYPE (arg))
10065 /* Template-parameter dependent expression. Just accept it for now.
10066 It will later be processed in convert_template_argument. */
10068 else if (same_type_p (TREE_TYPE (arg), tparm))
10070 else if ((strict & UNIFY_ALLOW_INTEGER)
10071 && (TREE_CODE (tparm) == INTEGER_TYPE
10072 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10073 /* Convert the ARG to the type of PARM; the deduced non-type
10074 template argument must exactly match the types of the
10075 corresponding parameter. */
10076 arg = fold (build_nop (TREE_TYPE (parm), arg));
10077 else if (uses_template_parms (tparm))
10078 /* We haven't deduced the type of this parameter yet. Try again
10084 TREE_VEC_ELT (targs, idx) = arg;
10089 /* A pointer-to-member constant can be unified only with
10090 another constant. */
10091 if (TREE_CODE (arg) != PTRMEM_CST)
10094 /* Just unify the class member. It would be useless (and possibly
10095 wrong, depending on the strict flags) to unify also
10096 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10097 arg refer to the same variable, even if through different
10098 classes. For instance:
10100 struct A { int x; };
10103 Unification of &A::x and &B::x must succeed. */
10104 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10105 PTRMEM_CST_MEMBER (arg), strict);
10110 if (TREE_CODE (arg) != POINTER_TYPE)
10113 /* [temp.deduct.call]
10115 A can be another pointer or pointer to member type that can
10116 be converted to the deduced A via a qualification
10117 conversion (_conv.qual_).
10119 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10120 This will allow for additional cv-qualification of the
10121 pointed-to types if appropriate. */
10123 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10124 /* The derived-to-base conversion only persists through one
10125 level of pointers. */
10126 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10128 return unify (tparms, targs, TREE_TYPE (parm),
10129 TREE_TYPE (arg), strict);
10132 case REFERENCE_TYPE:
10133 if (TREE_CODE (arg) != REFERENCE_TYPE)
10135 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10136 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10139 if (TREE_CODE (arg) != ARRAY_TYPE)
10141 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10142 != (TYPE_DOMAIN (arg) == NULL_TREE))
10144 if (TYPE_DOMAIN (parm) != NULL_TREE)
10149 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10150 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10152 /* Our representation of array types uses "N - 1" as the
10153 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10154 not an integer constant. */
10155 if (TREE_CODE (parm_max) == MINUS_EXPR)
10157 arg_max = fold_build2 (PLUS_EXPR,
10160 TREE_OPERAND (parm_max, 1));
10161 parm_max = TREE_OPERAND (parm_max, 0);
10164 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10167 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10168 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10175 case ENUMERAL_TYPE:
10177 if (TREE_CODE (arg) != TREE_CODE (parm))
10180 /* We have already checked cv-qualification at the top of the
10182 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10185 /* As far as unification is concerned, this wins. Later checks
10186 will invalidate it if necessary. */
10189 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10190 /* Type INTEGER_CST can come from ordinary constant template args. */
10192 while (TREE_CODE (arg) == NOP_EXPR)
10193 arg = TREE_OPERAND (arg, 0);
10195 if (TREE_CODE (arg) != INTEGER_CST)
10197 return !tree_int_cst_equal (parm, arg);
10202 if (TREE_CODE (arg) != TREE_VEC)
10204 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10206 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10207 if (unify (tparms, targs,
10208 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10216 if (TREE_CODE (arg) != TREE_CODE (parm))
10219 if (TYPE_PTRMEMFUNC_P (parm))
10221 if (!TYPE_PTRMEMFUNC_P (arg))
10224 return unify (tparms, targs,
10225 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10226 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10230 if (CLASSTYPE_TEMPLATE_INFO (parm))
10232 tree t = NULL_TREE;
10234 if (strict_in & UNIFY_ALLOW_DERIVED)
10236 /* First, we try to unify the PARM and ARG directly. */
10237 t = try_class_unification (tparms, targs,
10242 /* Fallback to the special case allowed in
10243 [temp.deduct.call]:
10245 If P is a class, and P has the form
10246 template-id, then A can be a derived class of
10247 the deduced A. Likewise, if P is a pointer to
10248 a class of the form template-id, A can be a
10249 pointer to a derived class pointed to by the
10251 t = get_template_base (tparms, targs, parm, arg);
10257 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10258 && (CLASSTYPE_TI_TEMPLATE (parm)
10259 == CLASSTYPE_TI_TEMPLATE (arg)))
10260 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10261 Then, we should unify `int' and `U'. */
10264 /* There's no chance of unification succeeding. */
10267 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10268 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10270 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10275 case FUNCTION_TYPE:
10276 if (TREE_CODE (arg) != TREE_CODE (parm))
10279 /* CV qualifications for methods can never be deduced, they must
10280 match exactly. We need to check them explicitly here,
10281 because type_unification_real treats them as any other
10282 cvqualified parameter. */
10283 if (TREE_CODE (parm) == METHOD_TYPE
10284 && (!check_cv_quals_for_unify
10286 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
10287 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
10290 if (unify (tparms, targs, TREE_TYPE (parm),
10291 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10293 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10294 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
10298 /* Unify a pointer to member with a pointer to member function, which
10299 deduces the type of the member as a function type. */
10300 if (TYPE_PTRMEMFUNC_P (arg))
10304 cp_cv_quals cv_quals;
10306 /* Check top-level cv qualifiers */
10307 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
10310 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10311 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
10314 /* Determine the type of the function we are unifying against. */
10315 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
10317 build_function_type (TREE_TYPE (method_type),
10318 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
10320 /* Extract the cv-qualifiers of the member function from the
10321 implicit object parameter and place them on the function
10322 type to be restored later. */
10324 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
10325 fntype = build_qualified_type (fntype, cv_quals);
10326 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
10329 if (TREE_CODE (arg) != OFFSET_TYPE)
10331 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10332 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10334 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10338 if (DECL_TEMPLATE_PARM_P (parm))
10339 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10340 if (arg != integral_constant_value (parm))
10345 case TEMPLATE_DECL:
10346 /* Matched cases are handled by the ARG == PARM test above. */
10350 gcc_assert (EXPR_P (parm));
10352 /* We must be looking at an expression. This can happen with
10356 void foo(S<I>, S<I + 2>);
10358 This is a "nondeduced context":
10362 The nondeduced contexts are:
10364 --A type that is a template-id in which one or more of
10365 the template-arguments is an expression that references
10366 a template-parameter.
10368 In these cases, we assume deduction succeeded, but don't
10369 actually infer any unifications. */
10371 if (!uses_template_parms (parm)
10372 && !template_args_equal (parm, arg))
10379 /* Note that DECL can be defined in this translation unit, if
10383 mark_definable (tree decl)
10386 DECL_NOT_REALLY_EXTERN (decl) = 1;
10387 FOR_EACH_CLONE (clone, decl)
10388 DECL_NOT_REALLY_EXTERN (clone) = 1;
10391 /* Called if RESULT is explicitly instantiated, or is a member of an
10392 explicitly instantiated class. */
10395 mark_decl_instantiated (tree result, int extern_p)
10397 SET_DECL_EXPLICIT_INSTANTIATION (result);
10399 /* If this entity has already been written out, it's too late to
10400 make any modifications. */
10401 if (TREE_ASM_WRITTEN (result))
10404 if (TREE_CODE (result) != FUNCTION_DECL)
10405 /* The TREE_PUBLIC flag for function declarations will have been
10406 set correctly by tsubst. */
10407 TREE_PUBLIC (result) = 1;
10409 /* This might have been set by an earlier implicit instantiation. */
10410 DECL_COMDAT (result) = 0;
10413 DECL_NOT_REALLY_EXTERN (result) = 0;
10416 mark_definable (result);
10417 /* Always make artificials weak. */
10418 if (DECL_ARTIFICIAL (result) && flag_weak)
10419 comdat_linkage (result);
10420 /* For WIN32 we also want to put explicit instantiations in
10421 linkonce sections. */
10422 else if (TREE_PUBLIC (result))
10423 maybe_make_one_only (result);
10426 /* If EXTERN_P, then this function will not be emitted -- unless
10427 followed by an explicit instantiation, at which point its linkage
10428 will be adjusted. If !EXTERN_P, then this function will be
10429 emitted here. In neither circumstance do we want
10430 import_export_decl to adjust the linkage. */
10431 DECL_INTERFACE_KNOWN (result) = 1;
10434 /* Given two function templates PAT1 and PAT2, return:
10436 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10437 -1 if PAT2 is more specialized than PAT1.
10438 0 if neither is more specialized.
10440 LEN indicates the number of parameters we should consider
10441 (defaulted parameters should not be considered).
10443 The 1998 std underspecified function template partial ordering, and
10444 DR214 addresses the issue. We take pairs of arguments, one from
10445 each of the templates, and deduce them against each other. One of
10446 the templates will be more specialized if all the *other*
10447 template's arguments deduce against its arguments and at least one
10448 of its arguments *does* *not* deduce against the other template's
10449 corresponding argument. Deduction is done as for class templates.
10450 The arguments used in deduction have reference and top level cv
10451 qualifiers removed. Iff both arguments were originally reference
10452 types *and* deduction succeeds in both directions, the template
10453 with the more cv-qualified argument wins for that pairing (if
10454 neither is more cv-qualified, they both are equal). Unlike regular
10455 deduction, after all the arguments have been deduced in this way,
10456 we do *not* verify the deduced template argument values can be
10457 substituted into non-deduced contexts, nor do we have to verify
10458 that all template arguments have been deduced. */
10461 more_specialized_fn (tree pat1, tree pat2, int len)
10463 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
10464 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
10465 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
10466 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
10467 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
10468 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
10469 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
10470 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
10474 /* If only one is a member function, they are unordered. */
10475 if (DECL_FUNCTION_MEMBER_P (decl1) != DECL_FUNCTION_MEMBER_P (decl2))
10478 /* Don't consider 'this' parameter. */
10479 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
10480 args1 = TREE_CHAIN (args1);
10481 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
10482 args2 = TREE_CHAIN (args2);
10484 /* If only one is a conversion operator, they are unordered. */
10485 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
10488 /* Consider the return type for a conversion function */
10489 if (DECL_CONV_FN_P (decl1))
10491 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
10492 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
10496 processing_template_decl++;
10500 tree arg1 = TREE_VALUE (args1);
10501 tree arg2 = TREE_VALUE (args2);
10502 int deduce1, deduce2;
10506 if (TREE_CODE (arg1) == REFERENCE_TYPE)
10508 arg1 = TREE_TYPE (arg1);
10509 quals1 = cp_type_quals (arg1);
10512 if (TREE_CODE (arg2) == REFERENCE_TYPE)
10514 arg2 = TREE_TYPE (arg2);
10515 quals2 = cp_type_quals (arg2);
10518 if ((quals1 < 0) != (quals2 < 0))
10520 /* Only of the args is a reference, see if we should apply
10521 array/function pointer decay to it. This is not part of
10522 DR214, but is, IMHO, consistent with the deduction rules
10523 for the function call itself, and with our earlier
10524 implementation of the underspecified partial ordering
10525 rules. (nathan). */
10528 switch (TREE_CODE (arg1))
10531 arg1 = TREE_TYPE (arg1);
10533 case FUNCTION_TYPE:
10534 arg1 = build_pointer_type (arg1);
10543 switch (TREE_CODE (arg2))
10546 arg2 = TREE_TYPE (arg2);
10548 case FUNCTION_TYPE:
10549 arg2 = build_pointer_type (arg2);
10558 arg1 = TYPE_MAIN_VARIANT (arg1);
10559 arg2 = TYPE_MAIN_VARIANT (arg2);
10561 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
10562 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
10568 if (better1 < 0 && better2 < 0)
10569 /* We've failed to deduce something in either direction.
10570 These must be unordered. */
10573 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
10575 /* Deduces in both directions, see if quals can
10576 disambiguate. Pretend the worse one failed to deduce. */
10577 if ((quals1 & quals2) == quals2)
10579 if ((quals1 & quals2) == quals1)
10582 if (deduce1 && !deduce2 && !better2)
10584 if (deduce2 && !deduce1 && !better1)
10587 args1 = TREE_CHAIN (args1);
10588 args2 = TREE_CHAIN (args2);
10591 processing_template_decl--;
10593 return (better1 > 0) - (better2 > 0);
10596 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10598 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10599 -1 if PAT2 is more specialized than PAT1.
10600 0 if neither is more specialized.
10602 FULL_ARGS is the full set of template arguments that triggers this
10603 partial ordering. */
10606 more_specialized_class (tree pat1, tree pat2, tree full_args)
10611 /* Just like what happens for functions, if we are ordering between
10612 different class template specializations, we may encounter dependent
10613 types in the arguments, and we need our dependency check functions
10614 to behave correctly. */
10615 ++processing_template_decl;
10616 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10617 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10621 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10622 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10625 --processing_template_decl;
10630 /* Return the template arguments that will produce the function signature
10631 DECL from the function template FN, with the explicit template
10632 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
10633 also match. Return NULL_TREE if no satisfactory arguments could be
10637 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
10639 int ntparms = DECL_NTPARMS (fn);
10640 tree targs = make_tree_vec (ntparms);
10642 tree decl_arg_types;
10644 /* Substitute the explicit template arguments into the type of DECL.
10645 The call to fn_type_unification will handle substitution into the
10647 decl_type = TREE_TYPE (decl);
10648 if (explicit_args && uses_template_parms (decl_type))
10651 tree converted_args;
10653 if (DECL_TEMPLATE_INFO (decl))
10654 tmpl = DECL_TI_TEMPLATE (decl);
10656 /* We can get here for some invalid specializations. */
10660 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10661 explicit_args, NULL_TREE,
10662 tf_none, /*require_all_arguments=*/0));
10663 if (converted_args == error_mark_node)
10666 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10667 if (decl_type == error_mark_node)
10671 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10672 /* Never do unification on the 'this' parameter. */
10673 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10674 decl_arg_types = TREE_CHAIN (decl_arg_types);
10676 if (fn_type_unification (fn, explicit_args, targs,
10678 (check_rettype || DECL_CONV_FN_P (fn)
10679 ? TREE_TYPE (decl_type) : NULL_TREE),
10680 DEDUCE_EXACT, LOOKUP_NORMAL))
10686 /* Return the innermost template arguments that, when applied to a
10687 template specialization whose innermost template parameters are
10688 TPARMS, and whose specialization arguments are PARMS, yield the
10691 For example, suppose we have:
10693 template <class T, class U> struct S {};
10694 template <class T> struct S<T*, int> {};
10696 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10697 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10698 int}. The resulting vector will be {double}, indicating that `T'
10699 is bound to `double'. */
10702 get_class_bindings (tree tparms, tree parms, tree args)
10704 int i, ntparms = TREE_VEC_LENGTH (tparms);
10705 tree vec = make_tree_vec (ntparms);
10707 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10711 for (i = 0; i < ntparms; ++i)
10712 if (! TREE_VEC_ELT (vec, i))
10715 if (verify_class_unification (vec, parms, args))
10721 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10722 Pick the most specialized template, and return the corresponding
10723 instantiation, or if there is no corresponding instantiation, the
10724 template itself. If there is no most specialized template,
10725 error_mark_node is returned. If there are no templates at all,
10726 NULL_TREE is returned. */
10729 most_specialized_instantiation (tree instantiations)
10733 if (!instantiations)
10736 ++processing_template_decl;
10738 champ = instantiations;
10739 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10743 if (get_bindings (TREE_VALUE (champ),
10744 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10745 NULL_TREE, /*check_ret=*/false))
10748 if (get_bindings (TREE_VALUE (fn),
10749 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10750 NULL_TREE, /*check_ret=*/false))
10756 /* Equally specialized, move to next function. If there
10757 is no next function, nothing's most specialized. */
10758 fn = TREE_CHAIN (fn);
10764 /* Now verify that champ is better than everything earlier in the
10765 instantiation list. */
10766 for (fn = instantiations; fn != champ; fn = TREE_CHAIN (fn))
10767 if (get_bindings (TREE_VALUE (champ),
10768 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10769 NULL_TREE, /*check_ret=*/false)
10770 || !get_bindings (TREE_VALUE (fn),
10771 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10772 NULL_TREE, /*check_ret=*/false))
10778 processing_template_decl--;
10781 return error_mark_node;
10783 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10786 /* Return the most specialized of the list of templates in FNS that can
10787 produce an instantiation matching DECL, given the explicit template
10788 arguments EXPLICIT_ARGS. */
10791 most_specialized (tree fns, tree decl, tree explicit_args)
10793 tree candidates = NULL_TREE;
10796 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10798 tree candidate = TREE_VALUE (fn);
10800 args = get_bindings (candidate, decl, explicit_args, /*check_ret=*/true);
10802 candidates = tree_cons (NULL_TREE, candidate, candidates);
10805 return most_specialized_instantiation (candidates);
10808 /* If DECL is a specialization of some template, return the most
10809 general such template. Otherwise, returns NULL_TREE.
10811 For example, given:
10813 template <class T> struct S { template <class U> void f(U); };
10815 if TMPL is `template <class U> void S<int>::f(U)' this will return
10816 the full template. This function will not trace past partial
10817 specializations, however. For example, given in addition:
10819 template <class T> struct S<T*> { template <class U> void f(U); };
10821 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10822 `template <class T> template <class U> S<T*>::f(U)'. */
10825 most_general_template (tree decl)
10827 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10828 an immediate specialization. */
10829 if (TREE_CODE (decl) == FUNCTION_DECL)
10831 if (DECL_TEMPLATE_INFO (decl)) {
10832 decl = DECL_TI_TEMPLATE (decl);
10834 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10835 template friend. */
10836 if (TREE_CODE (decl) != TEMPLATE_DECL)
10842 /* Look for more and more general templates. */
10843 while (DECL_TEMPLATE_INFO (decl))
10845 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10846 (See cp-tree.h for details.) */
10847 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10850 if (CLASS_TYPE_P (TREE_TYPE (decl))
10851 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10854 /* Stop if we run into an explicitly specialized class template. */
10855 if (!DECL_NAMESPACE_SCOPE_P (decl)
10856 && DECL_CONTEXT (decl)
10857 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10860 decl = DECL_TI_TEMPLATE (decl);
10866 /* Return the most specialized of the class template specializations
10867 of TMPL which can produce an instantiation matching ARGS, or
10868 error_mark_node if the choice is ambiguous. */
10871 most_specialized_class (tree tmpl, tree args)
10873 tree list = NULL_TREE;
10878 tmpl = most_general_template (tmpl);
10879 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10882 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10885 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10886 TREE_TYPE (list) = TREE_TYPE (t);
10895 t = TREE_CHAIN (t);
10896 for (; t; t = TREE_CHAIN (t))
10898 fate = more_specialized_class (champ, t, args);
10905 t = TREE_CHAIN (t);
10907 return error_mark_node;
10913 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10915 fate = more_specialized_class (champ, t, args);
10917 return error_mark_node;
10923 /* Explicitly instantiate DECL. */
10926 do_decl_instantiation (tree decl, tree storage)
10928 tree result = NULL_TREE;
10932 /* An error occurred, for which grokdeclarator has already issued
10933 an appropriate message. */
10935 else if (! DECL_LANG_SPECIFIC (decl))
10937 error ("explicit instantiation of non-template %q#D", decl);
10940 else if (TREE_CODE (decl) == VAR_DECL)
10942 /* There is an asymmetry here in the way VAR_DECLs and
10943 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10944 the latter, the DECL we get back will be marked as a
10945 template instantiation, and the appropriate
10946 DECL_TEMPLATE_INFO will be set up. This does not happen for
10947 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10948 should handle VAR_DECLs as it currently handles
10950 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10951 if (!result || TREE_CODE (result) != VAR_DECL)
10953 error ("no matching template for %qD found", decl);
10957 else if (TREE_CODE (decl) != FUNCTION_DECL)
10959 error ("explicit instantiation of %q#D", decl);
10965 /* Check for various error cases. Note that if the explicit
10966 instantiation is valid the RESULT will currently be marked as an
10967 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10968 until we get here. */
10970 if (DECL_TEMPLATE_SPECIALIZATION (result))
10972 /* DR 259 [temp.spec].
10974 Both an explicit instantiation and a declaration of an explicit
10975 specialization shall not appear in a program unless the explicit
10976 instantiation follows a declaration of the explicit specialization.
10978 For a given set of template parameters, if an explicit
10979 instantiation of a template appears after a declaration of an
10980 explicit specialization for that template, the explicit
10981 instantiation has no effect. */
10984 else if (DECL_EXPLICIT_INSTANTIATION (result))
10988 No program shall explicitly instantiate any template more
10991 We check DECL_NOT_REALLY_EXTERN so as not to complain when
10992 the first instantiation was `extern' and the second is not,
10993 and EXTERN_P for the opposite case. */
10994 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
10995 pedwarn ("duplicate explicit instantiation of %q#D", result);
10996 /* If an "extern" explicit instantiation follows an ordinary
10997 explicit instantiation, the template is instantiated. */
11001 else if (!DECL_IMPLICIT_INSTANTIATION (result))
11003 error ("no matching template for %qD found", result);
11006 else if (!DECL_TEMPLATE_INFO (result))
11008 pedwarn ("explicit instantiation of non-template %q#D", result);
11012 if (storage == NULL_TREE)
11014 else if (storage == ridpointers[(int) RID_EXTERN])
11016 if (pedantic && !in_system_header)
11017 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
11022 error ("storage class %qD applied to template instantiation", storage);
11024 mark_decl_instantiated (result, extern_p);
11026 instantiate_decl (result, /*defer_ok=*/1,
11027 /*expl_inst_class_mem_p=*/false);
11031 mark_class_instantiated (tree t, int extern_p)
11033 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
11034 SET_CLASSTYPE_INTERFACE_KNOWN (t);
11035 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
11036 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
11039 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
11040 rest_of_type_compilation (t, 1);
11044 /* Called from do_type_instantiation through binding_table_foreach to
11045 do recursive instantiation for the type bound in ENTRY. */
11047 bt_instantiate_type_proc (binding_entry entry, void *data)
11049 tree storage = *(tree *) data;
11051 if (IS_AGGR_TYPE (entry->type)
11052 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
11053 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
11056 /* Called from do_type_instantiation to instantiate a member
11057 (a member function or a static member variable) of an
11058 explicitly instantiated class template. */
11060 instantiate_class_member (tree decl, int extern_p)
11062 mark_decl_instantiated (decl, extern_p);
11064 instantiate_decl (decl, /*defer_ok=*/1,
11065 /*expl_inst_class_mem_p=*/true);
11068 /* Perform an explicit instantiation of template class T. STORAGE, if
11069 non-null, is the RID for extern, inline or static. COMPLAIN is
11070 nonzero if this is called from the parser, zero if called recursively,
11071 since the standard is unclear (as detailed below). */
11074 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
11079 int previous_instantiation_extern_p = 0;
11081 if (TREE_CODE (t) == TYPE_DECL)
11084 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
11086 error ("explicit instantiation of non-template type %qT", t);
11092 if (!COMPLETE_TYPE_P (t))
11094 if (complain & tf_error)
11095 error ("explicit instantiation of %q#T before definition of template",
11100 if (storage != NULL_TREE)
11102 if (pedantic && !in_system_header)
11103 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
11106 if (storage == ridpointers[(int) RID_INLINE])
11108 else if (storage == ridpointers[(int) RID_EXTERN])
11110 else if (storage == ridpointers[(int) RID_STATIC])
11114 error ("storage class %qD applied to template instantiation",
11120 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
11122 /* DR 259 [temp.spec].
11124 Both an explicit instantiation and a declaration of an explicit
11125 specialization shall not appear in a program unless the explicit
11126 instantiation follows a declaration of the explicit specialization.
11128 For a given set of template parameters, if an explicit
11129 instantiation of a template appears after a declaration of an
11130 explicit specialization for that template, the explicit
11131 instantiation has no effect. */
11134 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
11138 No program shall explicitly instantiate any template more
11141 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
11142 instantiation was `extern'. If EXTERN_P then the second is.
11143 These cases are OK. */
11144 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11146 if (!previous_instantiation_extern_p && !extern_p
11147 && (complain & tf_error))
11148 pedwarn ("duplicate explicit instantiation of %q#T", t);
11150 /* If we've already instantiated the template, just return now. */
11151 if (!CLASSTYPE_INTERFACE_ONLY (t))
11155 mark_class_instantiated (t, extern_p);
11163 /* In contrast to implicit instantiation, where only the
11164 declarations, and not the definitions, of members are
11165 instantiated, we have here:
11169 The explicit instantiation of a class template specialization
11170 implies the instantiation of all of its members not
11171 previously explicitly specialized in the translation unit
11172 containing the explicit instantiation.
11174 Of course, we can't instantiate member template classes, since
11175 we don't have any arguments for them. Note that the standard
11176 is unclear on whether the instantiation of the members are
11177 *explicit* instantiations or not. However, the most natural
11178 interpretation is that it should be an explicit instantiation. */
11181 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11182 if (TREE_CODE (tmp) == FUNCTION_DECL
11183 && DECL_TEMPLATE_INSTANTIATION (tmp))
11184 instantiate_class_member (tmp, extern_p);
11186 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11187 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11188 instantiate_class_member (tmp, extern_p);
11190 if (CLASSTYPE_NESTED_UTDS (t))
11191 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11192 bt_instantiate_type_proc, &storage);
11196 /* Given a function DECL, which is a specialization of TMPL, modify
11197 DECL to be a re-instantiation of TMPL with the same template
11198 arguments. TMPL should be the template into which tsubst'ing
11199 should occur for DECL, not the most general template.
11201 One reason for doing this is a scenario like this:
11204 void f(const T&, int i);
11206 void g() { f(3, 7); }
11209 void f(const T& t, const int i) { }
11211 Note that when the template is first instantiated, with
11212 instantiate_template, the resulting DECL will have no name for the
11213 first parameter, and the wrong type for the second. So, when we go
11214 to instantiate the DECL, we regenerate it. */
11217 regenerate_decl_from_template (tree decl, tree tmpl)
11219 /* The arguments used to instantiate DECL, from the most general
11224 args = DECL_TI_ARGS (decl);
11225 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11227 /* Make sure that we can see identifiers, and compute access
11229 push_access_scope (decl);
11231 if (TREE_CODE (decl) == FUNCTION_DECL)
11239 args_depth = TMPL_ARGS_DEPTH (args);
11240 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11241 if (args_depth > parms_depth)
11242 args = get_innermost_template_args (args, parms_depth);
11244 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11245 args, tf_error, NULL_TREE);
11247 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11250 /* Merge parameter declarations. */
11251 decl_parm = skip_artificial_parms_for (decl,
11252 DECL_ARGUMENTS (decl));
11254 = skip_artificial_parms_for (code_pattern,
11255 DECL_ARGUMENTS (code_pattern));
11261 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11262 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11263 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11265 parm_type = type_decays_to (parm_type);
11266 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11267 TREE_TYPE (decl_parm) = parm_type;
11268 attributes = DECL_ATTRIBUTES (pattern_parm);
11269 if (DECL_ATTRIBUTES (decl_parm) != attributes)
11271 DECL_ATTRIBUTES (decl_parm) = attributes;
11272 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
11274 decl_parm = TREE_CHAIN (decl_parm);
11275 pattern_parm = TREE_CHAIN (pattern_parm);
11278 /* Merge additional specifiers from the CODE_PATTERN. */
11279 if (DECL_DECLARED_INLINE_P (code_pattern)
11280 && !DECL_DECLARED_INLINE_P (decl))
11281 DECL_DECLARED_INLINE_P (decl) = 1;
11282 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11283 DECL_INLINE (decl) = 1;
11285 else if (TREE_CODE (decl) == VAR_DECL)
11286 DECL_INITIAL (decl) =
11287 tsubst_expr (DECL_INITIAL (code_pattern), args,
11288 tf_error, DECL_TI_TEMPLATE (decl));
11290 gcc_unreachable ();
11292 pop_access_scope (decl);
11295 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11296 substituted to get DECL. */
11299 template_for_substitution (tree decl)
11301 tree tmpl = DECL_TI_TEMPLATE (decl);
11303 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11304 for the instantiation. This is not always the most general
11305 template. Consider, for example:
11308 struct S { template <class U> void f();
11309 template <> void f<int>(); };
11311 and an instantiation of S<double>::f<int>. We want TD to be the
11312 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11313 while (/* An instantiation cannot have a definition, so we need a
11314 more general template. */
11315 DECL_TEMPLATE_INSTANTIATION (tmpl)
11316 /* We must also deal with friend templates. Given:
11318 template <class T> struct S {
11319 template <class U> friend void f() {};
11322 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11323 so far as the language is concerned, but that's still
11324 where we get the pattern for the instantiation from. On
11325 other hand, if the definition comes outside the class, say:
11327 template <class T> struct S {
11328 template <class U> friend void f();
11330 template <class U> friend void f() {}
11332 we don't need to look any further. That's what the check for
11333 DECL_INITIAL is for. */
11334 || (TREE_CODE (decl) == FUNCTION_DECL
11335 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11336 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11338 /* The present template, TD, should not be a definition. If it
11339 were a definition, we should be using it! Note that we
11340 cannot restructure the loop to just keep going until we find
11341 a template with a definition, since that might go too far if
11342 a specialization was declared, but not defined. */
11343 gcc_assert (TREE_CODE (decl) != VAR_DECL
11344 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11346 /* Fetch the more general template. */
11347 tmpl = DECL_TI_TEMPLATE (tmpl);
11353 /* Produce the definition of D, a _DECL generated from a template. If
11354 DEFER_OK is nonzero, then we don't have to actually do the
11355 instantiation now; we just have to do it sometime. Normally it is
11356 an error if this is an explicit instantiation but D is undefined.
11357 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
11358 explicitly instantiated class template. */
11361 instantiate_decl (tree d, int defer_ok,
11362 bool expl_inst_class_mem_p)
11364 tree tmpl = DECL_TI_TEMPLATE (d);
11371 bool pattern_defined;
11373 location_t saved_loc = input_location;
11375 /* This function should only be used to instantiate templates for
11376 functions and static member variables. */
11377 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11378 || TREE_CODE (d) == VAR_DECL);
11380 /* Variables are never deferred; if instantiation is required, they
11381 are instantiated right away. That allows for better code in the
11382 case that an expression refers to the value of the variable --
11383 if the variable has a constant value the referring expression can
11384 take advantage of that fact. */
11385 if (TREE_CODE (d) == VAR_DECL)
11388 /* Don't instantiate cloned functions. Instead, instantiate the
11389 functions they cloned. */
11390 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11391 d = DECL_CLONED_FUNCTION (d);
11393 if (DECL_TEMPLATE_INSTANTIATED (d))
11394 /* D has already been instantiated. It might seem reasonable to
11395 check whether or not D is an explicit instantiation, and, if so,
11396 stop here. But when an explicit instantiation is deferred
11397 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11398 is set, even though we still need to do the instantiation. */
11401 /* If we already have a specialization of this declaration, then
11402 there's no reason to instantiate it. Note that
11403 retrieve_specialization gives us both instantiations and
11404 specializations, so we must explicitly check
11405 DECL_TEMPLATE_SPECIALIZATION. */
11406 gen_tmpl = most_general_template (tmpl);
11407 gen_args = DECL_TI_ARGS (d);
11408 spec = retrieve_specialization (gen_tmpl, gen_args,
11409 /*class_specializations_p=*/false);
11410 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11413 /* This needs to happen before any tsubsting. */
11414 if (! push_tinst_level (d))
11417 timevar_push (TV_PARSE);
11419 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11420 for the instantiation. */
11421 td = template_for_substitution (d);
11422 code_pattern = DECL_TEMPLATE_RESULT (td);
11424 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11425 || DECL_TEMPLATE_SPECIALIZATION (td))
11426 /* In the case of a friend template whose definition is provided
11427 outside the class, we may have too many arguments. Drop the
11428 ones we don't need. The same is true for specializations. */
11429 args = get_innermost_template_args
11430 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11434 if (TREE_CODE (d) == FUNCTION_DECL)
11435 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11437 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11439 /* We may be in the middle of deferred access check. Disable it now. */
11440 push_deferring_access_checks (dk_no_deferred);
11442 /* Unless an explicit instantiation directive has already determined
11443 the linkage of D, remember that a definition is available for
11445 if (pattern_defined
11446 && !DECL_INTERFACE_KNOWN (d)
11447 && !DECL_NOT_REALLY_EXTERN (d))
11448 mark_definable (d);
11450 input_location = DECL_SOURCE_LOCATION (d);
11452 /* If D is a member of an explicitly instantiated class template,
11453 and no definition is available, treat it like an implicit
11455 if (!pattern_defined && expl_inst_class_mem_p
11456 && DECL_EXPLICIT_INSTANTIATION (d))
11458 DECL_NOT_REALLY_EXTERN (d) = 0;
11459 DECL_INTERFACE_KNOWN (d) = 0;
11460 SET_DECL_IMPLICIT_INSTANTIATION (d);
11465 /* Recheck the substitutions to obtain any warning messages
11466 about ignoring cv qualifiers. */
11467 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11468 tree type = TREE_TYPE (gen);
11470 /* Make sure that we can see identifiers, and compute access
11471 correctly. D is already the target FUNCTION_DECL with the
11473 push_access_scope (d);
11475 if (TREE_CODE (gen) == FUNCTION_DECL)
11477 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11478 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11479 tf_error | tf_warning, d);
11480 /* Don't simply tsubst the function type, as that will give
11481 duplicate warnings about poor parameter qualifications.
11482 The function arguments are the same as the decl_arguments
11483 without the top level cv qualifiers. */
11484 type = TREE_TYPE (type);
11486 tsubst (type, gen_args, tf_error | tf_warning, d);
11488 pop_access_scope (d);
11491 /* Do not instantiate templates that we know will be defined
11493 if (DECL_INTERFACE_KNOWN (d)
11494 && DECL_REALLY_EXTERN (d)
11495 && ! (TREE_CODE (d) == FUNCTION_DECL
11496 && DECL_INLINE (d)))
11498 /* Defer all other templates, unless we have been explicitly
11499 forbidden from doing so. We restore the source position here
11500 because it's used by add_pending_template. */
11501 else if (! pattern_defined || defer_ok)
11503 /* The definition of the static data member is now required so
11504 we must substitute the initializer. */
11505 if (TREE_CODE (d) == VAR_DECL
11506 && !DECL_INITIAL (d)
11507 && DECL_INITIAL (code_pattern))
11509 push_nested_class (DECL_CONTEXT (d));
11511 = tsubst_expr (DECL_INITIAL (code_pattern),
11513 tf_error | tf_warning, NULL_TREE);
11514 pop_nested_class ();
11517 input_location = saved_loc;
11519 if (at_eof && !pattern_defined
11520 && DECL_EXPLICIT_INSTANTIATION (d))
11523 The definition of a non-exported function template, a
11524 non-exported member function template, or a non-exported
11525 member function or static data member of a class template
11526 shall be present in every translation unit in which it is
11527 explicitly instantiated. */
11529 ("explicit instantiation of %qD but no definition available", d);
11531 add_pending_template (d);
11534 /* Tell the repository that D is available in this translation unit
11535 -- and see if it is supposed to be instantiated here. */
11536 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11538 /* In a PCH file, despite the fact that the repository hasn't
11539 requested instantiation in the PCH it is still possible that
11540 an instantiation will be required in a file that includes the
11543 add_pending_template (d);
11544 /* Instantiate inline functions so that the inliner can do its
11545 job, even though we'll not be emitting a copy of this
11547 if (!(TREE_CODE (d) == FUNCTION_DECL
11548 && flag_inline_trees
11549 && DECL_DECLARED_INLINE_P (d)))
11553 need_push = !cfun || !global_bindings_p ();
11555 push_to_top_level ();
11557 /* Mark D as instantiated so that recursive calls to
11558 instantiate_decl do not try to instantiate it again. */
11559 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11561 /* Regenerate the declaration in case the template has been modified
11562 by a subsequent redeclaration. */
11563 regenerate_decl_from_template (d, td);
11565 /* We already set the file and line above. Reset them now in case
11566 they changed as a result of calling regenerate_decl_from_template. */
11567 input_location = DECL_SOURCE_LOCATION (d);
11569 if (TREE_CODE (d) == VAR_DECL)
11571 /* Clear out DECL_RTL; whatever was there before may not be right
11572 since we've reset the type of the declaration. */
11573 SET_DECL_RTL (d, NULL_RTX);
11574 DECL_IN_AGGR_P (d) = 0;
11576 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11577 initializer. That function will defer actual emission until
11578 we have a chance to determine linkage. */
11579 DECL_EXTERNAL (d) = 0;
11581 /* Enter the scope of D so that access-checking works correctly. */
11582 push_nested_class (DECL_CONTEXT (d));
11583 cp_finish_decl (d, DECL_INITIAL (d), NULL_TREE, 0);
11584 pop_nested_class ();
11586 else if (TREE_CODE (d) == FUNCTION_DECL)
11588 htab_t saved_local_specializations;
11593 /* Save away the current list, in case we are instantiating one
11594 template from within the body of another. */
11595 saved_local_specializations = local_specializations;
11597 /* Set up the list of local specializations. */
11598 local_specializations = htab_create (37,
11599 hash_local_specialization,
11600 eq_local_specializations,
11603 /* Set up context. */
11604 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11606 /* Create substitution entries for the parameters. */
11607 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11608 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11609 spec_parm = DECL_ARGUMENTS (d);
11610 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11612 register_local_specialization (spec_parm, tmpl_parm);
11613 spec_parm = skip_artificial_parms_for (d, spec_parm);
11614 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11618 register_local_specialization (spec_parm, tmpl_parm);
11619 tmpl_parm = TREE_CHAIN (tmpl_parm);
11620 spec_parm = TREE_CHAIN (spec_parm);
11622 gcc_assert (!spec_parm);
11624 /* Substitute into the body of the function. */
11625 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11626 tf_error | tf_warning, tmpl);
11628 /* We don't need the local specializations any more. */
11629 htab_delete (local_specializations);
11630 local_specializations = saved_local_specializations;
11632 /* Finish the function. */
11633 d = finish_function (0);
11634 expand_or_defer_fn (d);
11637 /* We're not deferring instantiation any more. */
11638 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11641 pop_from_top_level ();
11644 input_location = saved_loc;
11645 pop_deferring_access_checks ();
11646 pop_tinst_level ();
11648 timevar_pop (TV_PARSE);
11653 /* Run through the list of templates that we wish we could
11654 instantiate, and instantiate any we can. RETRIES is the
11655 number of times we retry pending template instantiation. */
11658 instantiate_pending_templates (int retries)
11661 tree last = NULL_TREE;
11663 location_t saved_loc = input_location;
11664 int saved_in_system_header = in_system_header;
11666 /* Instantiating templates may trigger vtable generation. This in turn
11667 may require further template instantiations. We place a limit here
11668 to avoid infinite loop. */
11669 if (pending_templates && retries >= max_tinst_depth)
11671 error ("template instantiation depth exceeds maximum of %d"
11672 " instantiating %q+D, possibly from virtual table generation"
11673 " (use -ftemplate-depth-NN to increase the maximum)",
11674 max_tinst_depth, TREE_VALUE (pending_templates));
11682 t = &pending_templates;
11685 tree instantiation = TREE_VALUE (*t);
11687 reopen_tinst_level (TREE_PURPOSE (*t));
11689 if (TYPE_P (instantiation))
11693 if (!COMPLETE_TYPE_P (instantiation))
11695 instantiate_class_template (instantiation);
11696 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11697 for (fn = TYPE_METHODS (instantiation);
11699 fn = TREE_CHAIN (fn))
11700 if (! DECL_ARTIFICIAL (fn))
11701 instantiate_decl (fn,
11703 /*expl_inst_class_mem_p=*/false);
11704 if (COMPLETE_TYPE_P (instantiation))
11708 if (COMPLETE_TYPE_P (instantiation))
11709 /* If INSTANTIATION has been instantiated, then we don't
11710 need to consider it again in the future. */
11711 *t = TREE_CHAIN (*t);
11715 t = &TREE_CHAIN (*t);
11720 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11721 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11724 = instantiate_decl (instantiation,
11726 /*expl_inst_class_mem_p=*/false);
11727 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11731 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11732 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11733 /* If INSTANTIATION has been instantiated, then we don't
11734 need to consider it again in the future. */
11735 *t = TREE_CHAIN (*t);
11739 t = &TREE_CHAIN (*t);
11743 current_tinst_level = NULL_TREE;
11745 last_pending_template = last;
11747 while (reconsider);
11749 input_location = saved_loc;
11750 in_system_header = saved_in_system_header;
11753 /* Substitute ARGVEC into T, which is a list of initializers for
11754 either base class or a non-static data member. The TREE_PURPOSEs
11755 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11756 instantiate_decl. */
11759 tsubst_initializer_list (tree t, tree argvec)
11761 tree inits = NULL_TREE;
11763 for (; t; t = TREE_CHAIN (t))
11768 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11770 decl = expand_member_init (decl);
11771 if (decl && !DECL_P (decl))
11772 in_base_initializer = 1;
11774 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11776 in_base_initializer = 0;
11780 init = build_tree_list (decl, init);
11781 TREE_CHAIN (init) = inits;
11788 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11791 set_current_access_from_decl (tree decl)
11793 if (TREE_PRIVATE (decl))
11794 current_access_specifier = access_private_node;
11795 else if (TREE_PROTECTED (decl))
11796 current_access_specifier = access_protected_node;
11798 current_access_specifier = access_public_node;
11801 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11802 is the instantiation (which should have been created with
11803 start_enum) and ARGS are the template arguments to use. */
11806 tsubst_enum (tree tag, tree newtag, tree args)
11810 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11815 decl = TREE_VALUE (e);
11816 /* Note that in a template enum, the TREE_VALUE is the
11817 CONST_DECL, not the corresponding INTEGER_CST. */
11818 value = tsubst_expr (DECL_INITIAL (decl),
11819 args, tf_error | tf_warning,
11822 /* Give this enumeration constant the correct access. */
11823 set_current_access_from_decl (decl);
11825 /* Actually build the enumerator itself. */
11826 build_enumerator (DECL_NAME (decl), value, newtag);
11829 finish_enum (newtag);
11830 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11831 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11834 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11835 its type -- but without substituting the innermost set of template
11836 arguments. So, innermost set of template parameters will appear in
11840 get_mostly_instantiated_function_type (tree decl)
11848 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11849 targs = DECL_TI_ARGS (decl);
11850 tparms = DECL_TEMPLATE_PARMS (tmpl);
11851 parm_depth = TMPL_PARMS_DEPTH (tparms);
11853 /* There should be as many levels of arguments as there are levels
11855 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11857 fn_type = TREE_TYPE (tmpl);
11859 if (parm_depth == 1)
11860 /* No substitution is necessary. */
11864 int i, save_access_control;
11867 /* Replace the innermost level of the TARGS with NULL_TREEs to
11868 let tsubst know not to substitute for those parameters. */
11869 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11870 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11871 SET_TMPL_ARGS_LEVEL (partial_args, i,
11872 TMPL_ARGS_LEVEL (targs, i));
11873 SET_TMPL_ARGS_LEVEL (partial_args,
11874 TMPL_ARGS_DEPTH (targs),
11875 make_tree_vec (DECL_NTPARMS (tmpl)));
11877 /* Disable access control as this function is used only during
11879 save_access_control = flag_access_control;
11880 flag_access_control = 0;
11882 ++processing_template_decl;
11883 /* Now, do the (partial) substitution to figure out the
11884 appropriate function type. */
11885 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11886 --processing_template_decl;
11888 /* Substitute into the template parameters to obtain the real
11889 innermost set of parameters. This step is important if the
11890 innermost set of template parameters contains value
11891 parameters whose types depend on outer template parameters. */
11892 TREE_VEC_LENGTH (partial_args)--;
11893 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11895 flag_access_control = save_access_control;
11901 /* Return truthvalue if we're processing a template different from
11902 the last one involved in diagnostics. */
11904 problematic_instantiation_changed (void)
11906 return last_template_error_tick != tinst_level_tick;
11909 /* Remember current template involved in diagnostics. */
11911 record_last_problematic_instantiation (void)
11913 last_template_error_tick = tinst_level_tick;
11917 current_instantiation (void)
11919 return current_tinst_level;
11922 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11923 type. Return zero for ok, nonzero for disallowed. Issue error and
11924 warning messages under control of COMPLAIN. */
11927 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11929 if (INTEGRAL_TYPE_P (type))
11931 else if (POINTER_TYPE_P (type))
11933 else if (TYPE_PTR_TO_MEMBER_P (type))
11935 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11937 else if (TREE_CODE (type) == TYPENAME_TYPE)
11940 if (complain & tf_error)
11941 error ("%q#T is not a valid type for a template constant parameter", type);
11945 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11946 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11949 dependent_type_p_r (tree type)
11955 A type is dependent if it is:
11957 -- a template parameter. Template template parameters are types
11958 for us (since TYPE_P holds true for them) so we handle
11960 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11961 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11963 /* -- a qualified-id with a nested-name-specifier which contains a
11964 class-name that names a dependent type or whose unqualified-id
11965 names a dependent type. */
11966 if (TREE_CODE (type) == TYPENAME_TYPE)
11968 /* -- a cv-qualified type where the cv-unqualified type is
11970 type = TYPE_MAIN_VARIANT (type);
11971 /* -- a compound type constructed from any dependent type. */
11972 if (TYPE_PTR_TO_MEMBER_P (type))
11973 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11974 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11976 else if (TREE_CODE (type) == POINTER_TYPE
11977 || TREE_CODE (type) == REFERENCE_TYPE)
11978 return dependent_type_p (TREE_TYPE (type));
11979 else if (TREE_CODE (type) == FUNCTION_TYPE
11980 || TREE_CODE (type) == METHOD_TYPE)
11984 if (dependent_type_p (TREE_TYPE (type)))
11986 for (arg_type = TYPE_ARG_TYPES (type);
11988 arg_type = TREE_CHAIN (arg_type))
11989 if (dependent_type_p (TREE_VALUE (arg_type)))
11993 /* -- an array type constructed from any dependent type or whose
11994 size is specified by a constant expression that is
11995 value-dependent. */
11996 if (TREE_CODE (type) == ARRAY_TYPE)
11998 if (TYPE_DOMAIN (type)
11999 && ((value_dependent_expression_p
12000 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
12001 || (type_dependent_expression_p
12002 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
12004 return dependent_type_p (TREE_TYPE (type));
12007 /* -- a template-id in which either the template name is a template
12009 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
12011 /* ... or any of the template arguments is a dependent type or
12012 an expression that is type-dependent or value-dependent. */
12013 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
12014 && (any_dependent_template_arguments_p
12015 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
12018 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
12019 expression is not type-dependent, then it should already been
12021 if (TREE_CODE (type) == TYPEOF_TYPE)
12024 /* The standard does not specifically mention types that are local
12025 to template functions or local classes, but they should be
12026 considered dependent too. For example:
12028 template <int I> void f() {
12033 The size of `E' cannot be known until the value of `I' has been
12034 determined. Therefore, `E' must be considered dependent. */
12035 scope = TYPE_CONTEXT (type);
12036 if (scope && TYPE_P (scope))
12037 return dependent_type_p (scope);
12038 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
12039 return type_dependent_expression_p (scope);
12041 /* Other types are non-dependent. */
12045 /* Returns TRUE if TYPE is dependent, in the sense of
12046 [temp.dep.type]. */
12049 dependent_type_p (tree type)
12051 /* If there are no template parameters in scope, then there can't be
12052 any dependent types. */
12053 if (!processing_template_decl)
12056 /* If the type is NULL, we have not computed a type for the entity
12057 in question; in that case, the type is dependent. */
12061 /* Erroneous types can be considered non-dependent. */
12062 if (type == error_mark_node)
12065 /* If we have not already computed the appropriate value for TYPE,
12067 if (!TYPE_DEPENDENT_P_VALID (type))
12069 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
12070 TYPE_DEPENDENT_P_VALID (type) = 1;
12073 return TYPE_DEPENDENT_P (type);
12076 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
12079 dependent_scope_ref_p (tree expression, bool criterion (tree))
12084 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
12086 if (!TYPE_P (TREE_OPERAND (expression, 0)))
12089 scope = TREE_OPERAND (expression, 0);
12090 name = TREE_OPERAND (expression, 1);
12094 An id-expression is type-dependent if it contains a
12095 nested-name-specifier that contains a class-name that names a
12097 /* The suggested resolution to Core Issue 2 implies that if the
12098 qualifying type is the current class, then we must peek
12101 && currently_open_class (scope)
12102 && !criterion (name))
12104 if (dependent_type_p (scope))
12110 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
12111 [temp.dep.constexpr] */
12114 value_dependent_expression_p (tree expression)
12116 if (!processing_template_decl)
12119 /* A name declared with a dependent type. */
12120 if (DECL_P (expression) && type_dependent_expression_p (expression))
12123 switch (TREE_CODE (expression))
12125 case IDENTIFIER_NODE:
12126 /* A name that has not been looked up -- must be dependent. */
12129 case TEMPLATE_PARM_INDEX:
12130 /* A non-type template parm. */
12134 /* A non-type template parm. */
12135 if (DECL_TEMPLATE_PARM_P (expression))
12140 /* A constant with integral or enumeration type and is initialized
12141 with an expression that is value-dependent. */
12142 if (DECL_INITIAL (expression)
12143 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
12144 && value_dependent_expression_p (DECL_INITIAL (expression)))
12148 case DYNAMIC_CAST_EXPR:
12149 case STATIC_CAST_EXPR:
12150 case CONST_CAST_EXPR:
12151 case REINTERPRET_CAST_EXPR:
12153 /* These expressions are value-dependent if the type to which
12154 the cast occurs is dependent or the expression being casted
12155 is value-dependent. */
12157 tree type = TREE_TYPE (expression);
12159 if (dependent_type_p (type))
12162 /* A functional cast has a list of operands. */
12163 expression = TREE_OPERAND (expression, 0);
12166 /* If there are no operands, it must be an expression such
12167 as "int()". This should not happen for aggregate types
12168 because it would form non-constant expressions. */
12169 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12174 if (TREE_CODE (expression) == TREE_LIST)
12176 for (; expression; expression = TREE_CHAIN (expression))
12177 if (value_dependent_expression_p (TREE_VALUE (expression)))
12182 return value_dependent_expression_p (expression);
12187 /* A `sizeof' expression is value-dependent if the operand is
12189 expression = TREE_OPERAND (expression, 0);
12190 if (TYPE_P (expression))
12191 return dependent_type_p (expression);
12192 return type_dependent_expression_p (expression);
12195 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12197 case COMPONENT_REF:
12198 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12199 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12202 /* A CALL_EXPR is value-dependent if any argument is
12203 value-dependent. Why do we have to handle CALL_EXPRs in this
12204 function at all? First, some function calls, those for which
12205 value_dependent_expression_p is true, man appear in constant
12206 expressions. Second, there appear to be bugs which result in
12207 other CALL_EXPRs reaching this point. */
12209 tree function = TREE_OPERAND (expression, 0);
12210 tree args = TREE_OPERAND (expression, 1);
12212 if (value_dependent_expression_p (function))
12218 if (TREE_CODE (args) == TREE_LIST)
12220 for (; args; args = TREE_CHAIN (args))
12221 if (value_dependent_expression_p (TREE_VALUE (args)))
12226 return value_dependent_expression_p (args);
12230 /* A constant expression is value-dependent if any subexpression is
12231 value-dependent. */
12232 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12234 case tcc_reference:
12236 return (value_dependent_expression_p
12237 (TREE_OPERAND (expression, 0)));
12239 case tcc_comparison:
12241 return ((value_dependent_expression_p
12242 (TREE_OPERAND (expression, 0)))
12243 || (value_dependent_expression_p
12244 (TREE_OPERAND (expression, 1))));
12246 case tcc_expression:
12249 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12250 /* In some cases, some of the operands may be missing.
12251 (For example, in the case of PREDECREMENT_EXPR, the
12252 amount to increment by may be missing.) That doesn't
12253 make the expression dependent. */
12254 if (TREE_OPERAND (expression, i)
12255 && (value_dependent_expression_p
12256 (TREE_OPERAND (expression, i))))
12266 /* The expression is not value-dependent. */
12270 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12271 [temp.dep.expr]. */
12274 type_dependent_expression_p (tree expression)
12276 if (!processing_template_decl)
12279 if (expression == error_mark_node)
12282 /* An unresolved name is always dependent. */
12283 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12286 /* Some expression forms are never type-dependent. */
12287 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12288 || TREE_CODE (expression) == SIZEOF_EXPR
12289 || TREE_CODE (expression) == ALIGNOF_EXPR
12290 || TREE_CODE (expression) == TYPEID_EXPR
12291 || TREE_CODE (expression) == DELETE_EXPR
12292 || TREE_CODE (expression) == VEC_DELETE_EXPR
12293 || TREE_CODE (expression) == THROW_EXPR)
12296 /* The types of these expressions depends only on the type to which
12297 the cast occurs. */
12298 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12299 || TREE_CODE (expression) == STATIC_CAST_EXPR
12300 || TREE_CODE (expression) == CONST_CAST_EXPR
12301 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12302 || TREE_CODE (expression) == CAST_EXPR)
12303 return dependent_type_p (TREE_TYPE (expression));
12305 /* The types of these expressions depends only on the type created
12306 by the expression. */
12307 if (TREE_CODE (expression) == NEW_EXPR
12308 || TREE_CODE (expression) == VEC_NEW_EXPR)
12310 /* For NEW_EXPR tree nodes created inside a template, either
12311 the object type itself or a TREE_LIST may appear as the
12313 tree type = TREE_OPERAND (expression, 1);
12314 if (TREE_CODE (type) == TREE_LIST)
12315 /* This is an array type. We need to check array dimensions
12317 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12318 || value_dependent_expression_p
12319 (TREE_OPERAND (TREE_VALUE (type), 1));
12321 return dependent_type_p (type);
12324 if (TREE_CODE (expression) == SCOPE_REF
12325 && dependent_scope_ref_p (expression,
12326 type_dependent_expression_p))
12329 if (TREE_CODE (expression) == FUNCTION_DECL
12330 && DECL_LANG_SPECIFIC (expression)
12331 && DECL_TEMPLATE_INFO (expression)
12332 && (any_dependent_template_arguments_p
12333 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12336 if (TREE_CODE (expression) == TEMPLATE_DECL
12337 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12340 if (TREE_TYPE (expression) == unknown_type_node)
12342 if (TREE_CODE (expression) == ADDR_EXPR)
12343 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12344 if (TREE_CODE (expression) == COMPONENT_REF
12345 || TREE_CODE (expression) == OFFSET_REF)
12347 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12349 expression = TREE_OPERAND (expression, 1);
12350 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12353 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12354 if (TREE_CODE (expression) == SCOPE_REF)
12357 if (TREE_CODE (expression) == BASELINK)
12358 expression = BASELINK_FUNCTIONS (expression);
12360 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12362 if (any_dependent_template_arguments_p
12363 (TREE_OPERAND (expression, 1)))
12365 expression = TREE_OPERAND (expression, 0);
12367 gcc_assert (TREE_CODE (expression) == OVERLOAD
12368 || TREE_CODE (expression) == FUNCTION_DECL);
12372 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12374 expression = OVL_NEXT (expression);
12379 return (dependent_type_p (TREE_TYPE (expression)));
12382 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12383 contains a type-dependent expression. */
12386 any_type_dependent_arguments_p (tree args)
12390 tree arg = TREE_VALUE (args);
12392 if (type_dependent_expression_p (arg))
12394 args = TREE_CHAIN (args);
12399 /* Returns TRUE if the ARG (a template argument) is dependent. */
12402 dependent_template_arg_p (tree arg)
12404 if (!processing_template_decl)
12407 if (TREE_CODE (arg) == TEMPLATE_DECL
12408 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12409 return dependent_template_p (arg);
12410 else if (TYPE_P (arg))
12411 return dependent_type_p (arg);
12413 return (type_dependent_expression_p (arg)
12414 || value_dependent_expression_p (arg));
12417 /* Returns true if ARGS (a collection of template arguments) contains
12418 any dependent arguments. */
12421 any_dependent_template_arguments_p (tree args)
12429 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12431 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12432 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12433 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12440 /* Returns TRUE if the template TMPL is dependent. */
12443 dependent_template_p (tree tmpl)
12445 if (TREE_CODE (tmpl) == OVERLOAD)
12449 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12451 tmpl = OVL_CHAIN (tmpl);
12456 /* Template template parameters are dependent. */
12457 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12458 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12460 /* So are names that have not been looked up. */
12461 if (TREE_CODE (tmpl) == SCOPE_REF
12462 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12464 /* So are member templates of dependent classes. */
12465 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12466 return dependent_type_p (DECL_CONTEXT (tmpl));
12470 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12473 dependent_template_id_p (tree tmpl, tree args)
12475 return (dependent_template_p (tmpl)
12476 || any_dependent_template_arguments_p (args));
12479 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12480 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12481 can be found. Note that this function peers inside uninstantiated
12482 templates and therefore should be used only in extremely limited
12483 situations. ONLY_CURRENT_P restricts this peering to the currently
12484 open classes hierarchy (which is required when comparing types). */
12487 resolve_typename_type (tree type, bool only_current_p)
12495 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12497 scope = TYPE_CONTEXT (type);
12498 name = TYPE_IDENTIFIER (type);
12500 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12501 it first before we can figure out what NAME refers to. */
12502 if (TREE_CODE (scope) == TYPENAME_TYPE)
12503 scope = resolve_typename_type (scope, only_current_p);
12504 /* If we don't know what SCOPE refers to, then we cannot resolve the
12506 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12507 return error_mark_node;
12508 /* If the SCOPE is a template type parameter, we have no way of
12509 resolving the name. */
12510 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12512 /* If the SCOPE is not the current instantiation, there's no reason
12513 to look inside it. */
12514 if (only_current_p && !currently_open_class (scope))
12515 return error_mark_node;
12516 /* If SCOPE is a partial instantiation, it will not have a valid
12517 TYPE_FIELDS list, so use the original template. */
12518 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12519 /* Enter the SCOPE so that name lookup will be resolved as if we
12520 were in the class definition. In particular, SCOPE will no
12521 longer be considered a dependent type. */
12522 pushed_scope = push_scope (scope);
12523 /* Look up the declaration. */
12524 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12525 /* Obtain the set of qualifiers applied to the TYPE. */
12526 quals = cp_type_quals (type);
12527 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12528 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12530 type = error_mark_node;
12531 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12532 && TREE_CODE (decl) == TYPE_DECL)
12533 type = TREE_TYPE (decl);
12534 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12535 && DECL_CLASS_TEMPLATE_P (decl))
12539 /* Obtain the template and the arguments. */
12540 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12541 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12542 /* Instantiate the template. */
12543 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12544 /*entering_scope=*/0, tf_error | tf_user);
12547 type = error_mark_node;
12548 /* Qualify the resulting type. */
12549 if (type != error_mark_node && quals)
12550 type = cp_build_qualified_type (type, quals);
12551 /* Leave the SCOPE. */
12553 pop_scope (pushed_scope);
12558 /* EXPR is an expression which is not type-dependent. Return a proxy
12559 for EXPR that can be used to compute the types of larger
12560 expressions containing EXPR. */
12563 build_non_dependent_expr (tree expr)
12567 /* Preserve null pointer constants so that the type of things like
12568 "p == 0" where "p" is a pointer can be determined. */
12569 if (null_ptr_cst_p (expr))
12571 /* Preserve OVERLOADs; the functions must be available to resolve
12573 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12574 TREE_OPERAND (expr, 0) : expr);
12575 if (is_overloaded_fn (inner_expr)
12576 || TREE_CODE (inner_expr) == OFFSET_REF)
12578 /* There is no need to return a proxy for a variable. */
12579 if (TREE_CODE (expr) == VAR_DECL)
12581 /* Preserve string constants; conversions from string constants to
12582 "char *" are allowed, even though normally a "const char *"
12583 cannot be used to initialize a "char *". */
12584 if (TREE_CODE (expr) == STRING_CST)
12586 /* Preserve arithmetic constants, as an optimization -- there is no
12587 reason to create a new node. */
12588 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12590 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12591 There is at least one place where we want to know that a
12592 particular expression is a throw-expression: when checking a ?:
12593 expression, there are special rules if the second or third
12594 argument is a throw-expression. */
12595 if (TREE_CODE (expr) == THROW_EXPR)
12598 if (TREE_CODE (expr) == COND_EXPR)
12599 return build3 (COND_EXPR,
12601 TREE_OPERAND (expr, 0),
12602 (TREE_OPERAND (expr, 1)
12603 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12604 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12605 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12606 if (TREE_CODE (expr) == COMPOUND_EXPR
12607 && !COMPOUND_EXPR_OVERLOADED (expr))
12608 return build2 (COMPOUND_EXPR,
12610 TREE_OPERAND (expr, 0),
12611 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12613 /* Otherwise, build a NON_DEPENDENT_EXPR.
12615 REFERENCE_TYPEs are not stripped for expressions in templates
12616 because doing so would play havoc with mangling. Consider, for
12619 template <typename T> void f<T& g>() { g(); }
12621 In the body of "f", the expression for "g" will have
12622 REFERENCE_TYPE, even though the standard says that it should
12623 not. The reason is that we must preserve the syntactic form of
12624 the expression so that mangling (say) "f<g>" inside the body of
12625 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12627 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12630 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12631 Return a new TREE_LIST with the various arguments replaced with
12632 equivalent non-dependent expressions. */
12635 build_non_dependent_args (tree args)
12640 new_args = NULL_TREE;
12641 for (a = args; a; a = TREE_CHAIN (a))
12642 new_args = tree_cons (NULL_TREE,
12643 build_non_dependent_expr (TREE_VALUE (a)),
12645 return nreverse (new_args);
12648 #include "gt-cp-pt.h"