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 /* Even if the original location is out of scope, the
6666 newly substituted one is not. */
6667 DECL_DEAD_FOR_LOCAL (r) = 0;
6668 DECL_INITIALIZED_P (r) = 0;
6669 DECL_TEMPLATE_INSTANTIATED (r) = 0;
6670 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6671 if (type == error_mark_node)
6672 return error_mark_node;
6673 type = complete_type (type);
6674 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6675 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6676 type = check_var_type (DECL_NAME (r), type);
6678 else if (DECL_SELF_REFERENCE_P (t))
6679 SET_DECL_SELF_REFERENCE_P (r);
6680 TREE_TYPE (r) = type;
6681 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6682 DECL_CONTEXT (r) = ctx;
6683 /* Clear out the mangled name and RTL for the instantiation. */
6684 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6685 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6686 SET_DECL_RTL (r, NULL_RTX);
6687 /* The initializer must not be expanded until it is required;
6689 DECL_INITIAL (r) = NULL_TREE;
6690 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6691 SET_DECL_RTL (r, NULL_RTX);
6692 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6696 /* A static data member declaration is always marked
6697 external when it is declared in-class, even if an
6698 initializer is present. We mimic the non-template
6700 DECL_EXTERNAL (r) = 1;
6702 register_specialization (r, gen_tmpl, argvec);
6703 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6704 SET_DECL_IMPLICIT_INSTANTIATION (r);
6707 register_local_specialization (r, t);
6709 TREE_CHAIN (r) = NULL_TREE;
6718 /* Restore the file and line information. */
6719 input_location = saved_loc;
6724 /* Substitute into the ARG_TYPES of a function type. */
6727 tsubst_arg_types (tree arg_types,
6729 tsubst_flags_t complain,
6732 tree remaining_arg_types;
6735 tree result = NULL_TREE;
6737 if (!arg_types || arg_types == void_list_node)
6740 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6741 args, complain, in_decl);
6742 if (remaining_arg_types == error_mark_node)
6743 return error_mark_node;
6745 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6746 if (type == error_mark_node)
6747 return error_mark_node;
6748 if (VOID_TYPE_P (type))
6750 if (complain & tf_error)
6752 error ("invalid parameter type %qT", type);
6754 error ("in declaration %q+D", in_decl);
6756 return error_mark_node;
6759 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6760 top-level qualifiers as required. */
6761 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6763 /* We do not substitute into default arguments here. The standard
6764 mandates that they be instantiated only when needed, which is
6765 done in build_over_call. */
6766 default_arg = TREE_PURPOSE (arg_types);
6768 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
6770 /* We've instantiated a template before its default arguments
6771 have been parsed. This can happen for a nested template
6772 class, and is not an error unless we require the default
6773 argument in a call of this function. */
6774 result = tree_cons (default_arg, type, remaining_arg_types);
6775 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), result);
6778 result = hash_tree_cons (default_arg, type, remaining_arg_types);
6783 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6784 *not* handle the exception-specification for FNTYPE, because the
6785 initial substitution of explicitly provided template parameters
6786 during argument deduction forbids substitution into the
6787 exception-specification:
6791 All references in the function type of the function template to the
6792 corresponding template parameters are replaced by the specified tem-
6793 plate argument values. If a substitution in a template parameter or
6794 in the function type of the function template results in an invalid
6795 type, type deduction fails. [Note: The equivalent substitution in
6796 exception specifications is done only when the function is instanti-
6797 ated, at which point a program is ill-formed if the substitution
6798 results in an invalid type.] */
6801 tsubst_function_type (tree t,
6803 tsubst_flags_t complain,
6810 /* The TYPE_CONTEXT is not used for function/method types. */
6811 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6813 /* Substitute the return type. */
6814 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6815 if (return_type == error_mark_node)
6816 return error_mark_node;
6817 /* The standard does not presently indicate that creation of a
6818 function type with an invalid return type is a deduction failure.
6819 However, that is clearly analogous to creating an array of "void"
6820 or a reference to a reference. This is core issue #486. */
6821 if (TREE_CODE (return_type) == ARRAY_TYPE
6822 || TREE_CODE (return_type) == FUNCTION_TYPE)
6824 if (complain & tf_error)
6826 if (TREE_CODE (return_type) == ARRAY_TYPE)
6827 error ("function returning an array");
6829 error ("function returning a function");
6831 return error_mark_node;
6834 /* Substitute the argument types. */
6835 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6837 if (arg_types == error_mark_node)
6838 return error_mark_node;
6840 /* Construct a new type node and return it. */
6841 if (TREE_CODE (t) == FUNCTION_TYPE)
6842 fntype = build_function_type (return_type, arg_types);
6845 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6846 if (! IS_AGGR_TYPE (r))
6850 Type deduction may fail for any of the following
6853 -- Attempting to create "pointer to member of T" when T
6854 is not a class type. */
6855 if (complain & tf_error)
6856 error ("creating pointer to member function of non-class type %qT",
6858 return error_mark_node;
6861 fntype = build_method_type_directly (r, return_type,
6862 TREE_CHAIN (arg_types));
6864 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6865 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6870 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6871 ARGS into that specification, and return the substituted
6872 specification. If there is no specification, return NULL_TREE. */
6875 tsubst_exception_specification (tree fntype,
6877 tsubst_flags_t complain,
6883 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6884 new_specs = NULL_TREE;
6887 if (! TREE_VALUE (specs))
6893 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6894 if (spec == error_mark_node)
6896 new_specs = add_exception_specifier (new_specs, spec, complain);
6897 specs = TREE_CHAIN (specs);
6903 /* Substitute into the PARMS of a call-declarator. */
6906 tsubst_call_declarator_parms (tree parms,
6908 tsubst_flags_t complain,
6915 if (!parms || parms == void_list_node)
6918 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6919 args, complain, in_decl);
6921 /* Figure out the type of this parameter. */
6922 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6924 /* Figure out the default argument as well. Note that we use
6925 tsubst_expr since the default argument is really an expression. */
6926 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6928 /* Chain this parameter on to the front of those we have already
6929 processed. We don't use hash_tree_cons because that function
6930 doesn't check TREE_PARMLIST. */
6931 new_parms = tree_cons (defarg, type, new_parms);
6936 /* Take the tree structure T and replace template parameters used
6937 therein with the argument vector ARGS. IN_DECL is an associated
6938 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6939 Issue error and warning messages under control of COMPLAIN. Note
6940 that we must be relatively non-tolerant of extensions here, in
6941 order to preserve conformance; if we allow substitutions that
6942 should not be allowed, we may allow argument deductions that should
6943 not succeed, and therefore report ambiguous overload situations
6944 where there are none. In theory, we could allow the substitution,
6945 but indicate that it should have failed, and allow our caller to
6946 make sure that the right thing happens, but we don't try to do this
6949 This function is used for dealing with types, decls and the like;
6950 for expressions, use tsubst_expr or tsubst_copy. */
6953 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6957 if (t == NULL_TREE || t == error_mark_node
6958 || t == integer_type_node
6959 || t == void_type_node
6960 || t == char_type_node
6961 || t == unknown_type_node
6962 || TREE_CODE (t) == NAMESPACE_DECL)
6966 return tsubst_decl (t, args, complain);
6968 if (TREE_CODE (t) == IDENTIFIER_NODE)
6969 type = IDENTIFIER_TYPE_VALUE (t);
6971 type = TREE_TYPE (t);
6973 gcc_assert (type != unknown_type_node);
6976 && TREE_CODE (t) != TYPENAME_TYPE
6977 && TREE_CODE (t) != IDENTIFIER_NODE
6978 && TREE_CODE (t) != FUNCTION_TYPE
6979 && TREE_CODE (t) != METHOD_TYPE)
6980 type = tsubst (type, args, complain, in_decl);
6981 if (type == error_mark_node)
6982 return error_mark_node;
6984 switch (TREE_CODE (t))
6989 return tsubst_aggr_type (t, args, complain, in_decl,
6990 /*entering_scope=*/0);
6993 case IDENTIFIER_NODE:
7005 if (t == integer_type_node)
7008 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
7009 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
7013 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
7015 /* The array dimension behaves like a non-type template arg,
7016 in that we want to fold it as much as possible. */
7017 max = tsubst_template_arg (omax, args, complain, in_decl);
7018 max = fold_decl_constant_value (max);
7020 if (integer_zerop (omax))
7022 /* Still allow an explicit array of size zero. */
7024 pedwarn ("creating array with size zero");
7026 else if (integer_zerop (max)
7027 || (TREE_CODE (max) == INTEGER_CST
7028 && INT_CST_LT (max, integer_zero_node)))
7032 Type deduction may fail for any of the following
7035 Attempting to create an array with a size that is
7036 zero or negative. */
7037 if (complain & tf_error)
7038 error ("creating array with size zero (%qE)", max);
7040 return error_mark_node;
7043 return compute_array_index_type (NULL_TREE, max);
7046 case TEMPLATE_TYPE_PARM:
7047 case TEMPLATE_TEMPLATE_PARM:
7048 case BOUND_TEMPLATE_TEMPLATE_PARM:
7049 case TEMPLATE_PARM_INDEX:
7054 tree arg = NULL_TREE;
7058 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7059 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7060 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7061 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7063 idx = TEMPLATE_TYPE_IDX (t);
7064 level = TEMPLATE_TYPE_LEVEL (t);
7068 idx = TEMPLATE_PARM_IDX (t);
7069 level = TEMPLATE_PARM_LEVEL (t);
7072 levels = TMPL_ARGS_DEPTH (args);
7073 if (level <= levels)
7074 arg = TMPL_ARG (args, level, idx);
7076 if (arg == error_mark_node)
7077 return error_mark_node;
7078 else if (arg != NULL_TREE)
7080 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7082 gcc_assert (TYPE_P (arg));
7083 return cp_build_qualified_type_real
7084 (arg, cp_type_quals (arg) | cp_type_quals (t),
7085 complain | tf_ignore_bad_quals);
7087 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7089 /* We are processing a type constructed from a
7090 template template parameter. */
7091 tree argvec = tsubst (TYPE_TI_ARGS (t),
7092 args, complain, in_decl);
7093 if (argvec == error_mark_node)
7094 return error_mark_node;
7096 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7097 are resolving nested-types in the signature of a
7098 member function templates. Otherwise ARG is a
7099 TEMPLATE_DECL and is the real template to be
7101 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7102 arg = TYPE_NAME (arg);
7104 r = lookup_template_class (arg,
7107 /*entering_scope=*/0,
7109 return cp_build_qualified_type_real
7110 (r, TYPE_QUALS (t), complain);
7113 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7118 /* This can happen during the attempted tsubst'ing in
7119 unify. This means that we don't yet have any information
7120 about the template parameter in question. */
7123 /* If we get here, we must have been looking at a parm for a
7124 more deeply nested template. Make a new version of this
7125 template parameter, but with a lower level. */
7126 switch (TREE_CODE (t))
7128 case TEMPLATE_TYPE_PARM:
7129 case TEMPLATE_TEMPLATE_PARM:
7130 case BOUND_TEMPLATE_TEMPLATE_PARM:
7131 if (cp_type_quals (t))
7133 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7134 r = cp_build_qualified_type_real
7135 (r, cp_type_quals (t),
7136 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7137 ? tf_ignore_bad_quals : 0));
7142 TEMPLATE_TYPE_PARM_INDEX (r)
7143 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7145 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7146 TYPE_MAIN_VARIANT (r) = r;
7147 TYPE_POINTER_TO (r) = NULL_TREE;
7148 TYPE_REFERENCE_TO (r) = NULL_TREE;
7150 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7152 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7154 if (argvec == error_mark_node)
7155 return error_mark_node;
7157 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7158 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7163 case TEMPLATE_PARM_INDEX:
7164 r = reduce_template_parm_level (t, type, levels);
7176 tree purpose, value, chain;
7178 if (t == void_list_node)
7181 purpose = TREE_PURPOSE (t);
7184 purpose = tsubst (purpose, args, complain, in_decl);
7185 if (purpose == error_mark_node)
7186 return error_mark_node;
7188 value = TREE_VALUE (t);
7191 value = tsubst (value, args, complain, in_decl);
7192 if (value == error_mark_node)
7193 return error_mark_node;
7195 chain = TREE_CHAIN (t);
7196 if (chain && chain != void_type_node)
7198 chain = tsubst (chain, args, complain, in_decl);
7199 if (chain == error_mark_node)
7200 return error_mark_node;
7202 if (purpose == TREE_PURPOSE (t)
7203 && value == TREE_VALUE (t)
7204 && chain == TREE_CHAIN (t))
7206 return hash_tree_cons (purpose, value, chain);
7210 /* We should never be tsubsting a binfo. */
7214 /* A vector of template arguments. */
7216 return tsubst_template_args (t, args, complain, in_decl);
7219 case REFERENCE_TYPE:
7221 enum tree_code code;
7223 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7226 code = TREE_CODE (t);
7231 Type deduction may fail for any of the following
7234 -- Attempting to create a pointer to reference type.
7235 -- Attempting to create a reference to a reference type or
7236 a reference to void. */
7237 if (TREE_CODE (type) == REFERENCE_TYPE
7238 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7240 static location_t last_loc;
7242 /* We keep track of the last time we issued this error
7243 message to avoid spewing a ton of messages during a
7244 single bad template instantiation. */
7245 if (complain & tf_error
7246 #ifdef USE_MAPPED_LOCATION
7247 && last_loc != input_location
7249 && (last_loc.line != input_line
7250 || last_loc.file != input_filename)
7254 if (TREE_CODE (type) == VOID_TYPE)
7255 error ("forming reference to void");
7257 error ("forming %s to reference type %qT",
7258 (code == POINTER_TYPE) ? "pointer" : "reference",
7260 last_loc = input_location;
7263 return error_mark_node;
7265 else if (code == POINTER_TYPE)
7267 r = build_pointer_type (type);
7268 if (TREE_CODE (type) == METHOD_TYPE)
7269 r = build_ptrmemfunc_type (r);
7272 r = build_reference_type (type);
7273 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7275 if (r != error_mark_node)
7276 /* Will this ever be needed for TYPE_..._TO values? */
7283 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7284 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7288 Type deduction may fail for any of the following
7291 -- Attempting to create "pointer to member of T" when T
7292 is not a class type. */
7293 if (complain & tf_error)
7294 error ("creating pointer to member of non-class type %qT", r);
7295 return error_mark_node;
7297 if (TREE_CODE (type) == REFERENCE_TYPE)
7299 if (complain & tf_error)
7300 error ("creating pointer to member reference type %qT", type);
7301 return error_mark_node;
7303 if (TREE_CODE (type) == VOID_TYPE)
7305 if (complain & tf_error)
7306 error ("creating pointer to member of type void");
7307 return error_mark_node;
7309 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7310 if (TREE_CODE (type) == FUNCTION_TYPE)
7312 /* The type of the implicit object parameter gets its
7313 cv-qualifiers from the FUNCTION_TYPE. */
7315 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
7316 cp_type_quals (type));
7318 method_type = build_method_type_directly (this_type,
7320 TYPE_ARG_TYPES (type));
7321 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
7322 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
7326 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7335 fntype = tsubst_function_type (t, args, complain, in_decl);
7336 if (fntype == error_mark_node)
7337 return error_mark_node;
7339 /* Substitute the exception specification. */
7340 specs = tsubst_exception_specification (t, args, complain,
7342 if (specs == error_mark_node)
7343 return error_mark_node;
7345 fntype = build_exception_variant (fntype, specs);
7350 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7351 if (domain == error_mark_node)
7352 return error_mark_node;
7354 /* As an optimization, we avoid regenerating the array type if
7355 it will obviously be the same as T. */
7356 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7359 /* These checks should match the ones in grokdeclarator.
7363 The deduction may fail for any of the following reasons:
7365 -- Attempting to create an array with an element type that
7366 is void, a function type, or a reference type, or [DR337]
7367 an abstract class type. */
7368 if (TREE_CODE (type) == VOID_TYPE
7369 || TREE_CODE (type) == FUNCTION_TYPE
7370 || TREE_CODE (type) == REFERENCE_TYPE)
7372 if (complain & tf_error)
7373 error ("creating array of %qT", type);
7374 return error_mark_node;
7376 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7378 if (complain & tf_error)
7379 error ("creating array of %qT, which is an abstract class type",
7381 return error_mark_node;
7384 r = build_cplus_array_type (type, domain);
7391 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7392 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7394 if (e1 == error_mark_node || e2 == error_mark_node)
7395 return error_mark_node;
7397 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
7403 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7404 if (e == error_mark_node)
7405 return error_mark_node;
7407 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
7412 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7413 in_decl, /*entering_scope=*/1);
7414 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7417 if (ctx == error_mark_node || f == error_mark_node)
7418 return error_mark_node;
7420 if (!IS_AGGR_TYPE (ctx))
7422 if (complain & tf_error)
7423 error ("%qT is not a class, struct, or union type", ctx);
7424 return error_mark_node;
7426 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7428 /* Normally, make_typename_type does not require that the CTX
7429 have complete type in order to allow things like:
7431 template <class T> struct S { typename S<T>::X Y; };
7433 But, such constructs have already been resolved by this
7434 point, so here CTX really should have complete type, unless
7435 it's a partial instantiation. */
7436 ctx = complete_type (ctx);
7437 if (!COMPLETE_TYPE_P (ctx))
7439 if (complain & tf_error)
7440 cxx_incomplete_type_error (NULL_TREE, ctx);
7441 return error_mark_node;
7445 f = make_typename_type (ctx, f, typename_type,
7446 (complain & tf_error) | tf_keep_type_decl);
7447 if (f == error_mark_node)
7449 if (TREE_CODE (f) == TYPE_DECL)
7451 complain |= tf_ignore_bad_quals;
7455 if (TREE_CODE (f) != TYPENAME_TYPE)
7457 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7458 error ("%qT resolves to %qT, which is not an enumeration type",
7460 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7461 error ("%qT resolves to %qT, which is is not a class type",
7465 return cp_build_qualified_type_real
7466 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7469 case UNBOUND_CLASS_TEMPLATE:
7471 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7472 in_decl, /*entering_scope=*/1);
7473 tree name = TYPE_IDENTIFIER (t);
7474 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7476 if (ctx == error_mark_node || name == error_mark_node)
7477 return error_mark_node;
7480 parm_list = tsubst_template_parms (parm_list, args, complain);
7481 return make_unbound_class_template (ctx, name, parm_list, complain);
7491 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7492 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7493 if (e1 == error_mark_node || e2 == error_mark_node)
7494 return error_mark_node;
7496 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7501 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7502 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7503 if (e1 == error_mark_node || e2 == error_mark_node)
7504 return error_mark_node;
7506 return build_nt (TREE_CODE (t), e1, e2);
7513 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7514 complain, in_decl));
7515 return cp_build_qualified_type_real (type,
7517 | cp_type_quals (type),
7522 sorry ("use of %qs in template",
7523 tree_code_name [(int) TREE_CODE (t)]);
7524 return error_mark_node;
7528 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7529 type of the expression on the left-hand side of the "." or "->"
7533 tsubst_baselink (tree baselink, tree object_type,
7534 tree args, tsubst_flags_t complain, tree in_decl)
7537 tree qualifying_scope;
7539 tree template_args = 0;
7540 bool template_id_p = false;
7542 /* A baselink indicates a function from a base class. The
7543 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7544 non-dependent types; otherwise, the lookup could not have
7545 succeeded. However, they may indicate bases of the template
7546 class, rather than the instantiated class.
7548 In addition, lookups that were not ambiguous before may be
7549 ambiguous now. Therefore, we perform the lookup again. */
7550 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7551 fns = BASELINK_FUNCTIONS (baselink);
7552 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7554 template_id_p = true;
7555 template_args = TREE_OPERAND (fns, 1);
7556 fns = TREE_OPERAND (fns, 0);
7558 template_args = tsubst_template_args (template_args, args,
7561 name = DECL_NAME (get_first_fn (fns));
7562 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7564 /* If lookup found a single function, mark it as used at this
7565 point. (If it lookup found multiple functions the one selected
7566 later by overload resolution will be marked as used at that
7568 if (BASELINK_P (baselink))
7569 fns = BASELINK_FUNCTIONS (baselink);
7570 if (!template_id_p && !really_overloaded_fn (fns))
7571 mark_used (OVL_CURRENT (fns));
7573 /* Add back the template arguments, if present. */
7574 if (BASELINK_P (baselink) && template_id_p)
7575 BASELINK_FUNCTIONS (baselink)
7576 = build_nt (TEMPLATE_ID_EXPR,
7577 BASELINK_FUNCTIONS (baselink),
7581 object_type = current_class_type;
7582 return adjust_result_of_qualified_name_lookup (baselink,
7587 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7588 true if the qualified-id will be a postfix-expression in-and-of
7589 itself; false if more of the postfix-expression follows the
7590 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7594 tsubst_qualified_id (tree qualified_id, tree args,
7595 tsubst_flags_t complain, tree in_decl,
7596 bool done, bool address_p)
7604 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7606 /* Figure out what name to look up. */
7607 name = TREE_OPERAND (qualified_id, 1);
7608 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7611 template_args = TREE_OPERAND (name, 1);
7613 template_args = tsubst_template_args (template_args, args,
7615 name = TREE_OPERAND (name, 0);
7619 is_template = false;
7620 template_args = NULL_TREE;
7623 /* Substitute into the qualifying scope. When there are no ARGS, we
7624 are just trying to simplify a non-dependent expression. In that
7625 case the qualifying scope may be dependent, and, in any case,
7626 substituting will not help. */
7627 scope = TREE_OPERAND (qualified_id, 0);
7630 scope = tsubst (scope, args, complain, in_decl);
7631 expr = tsubst_copy (name, args, complain, in_decl);
7636 if (dependent_type_p (scope))
7637 return build_nt (SCOPE_REF, scope, expr);
7639 if (!BASELINK_P (name) && !DECL_P (expr))
7641 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7642 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7643 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7645 if (complain & tf_error)
7647 error ("dependent-name %qE is parsed as a non-type, but "
7648 "instantiation yields a type", qualified_id);
7649 inform ("say %<typename %E%> if a type is meant", qualified_id);
7651 return error_mark_node;
7657 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7659 /* Remember that there was a reference to this entity. */
7663 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7665 if (complain & tf_error)
7666 qualified_name_lookup_error (scope,
7667 TREE_OPERAND (qualified_id, 1),
7669 return error_mark_node;
7673 expr = lookup_template_function (expr, template_args);
7675 if (expr == error_mark_node && complain & tf_error)
7676 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7678 else if (TYPE_P (scope))
7680 expr = (adjust_result_of_qualified_name_lookup
7681 (expr, scope, current_class_type));
7682 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7685 if (TREE_CODE (expr) != SCOPE_REF)
7686 expr = convert_from_reference (expr);
7691 /* Like tsubst, but deals with expressions. This function just replaces
7692 template parms; to finish processing the resultant expression, use
7696 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7698 enum tree_code code;
7701 if (t == NULL_TREE || t == error_mark_node)
7704 code = TREE_CODE (t);
7709 r = retrieve_local_specialization (t);
7710 gcc_assert (r != NULL);
7719 if (DECL_TEMPLATE_PARM_P (t))
7720 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7721 /* There is no need to substitute into namespace-scope
7723 if (DECL_NAMESPACE_SCOPE_P (t))
7725 /* If ARGS is NULL, then T is known to be non-dependent. */
7726 if (args == NULL_TREE)
7727 return integral_constant_value (t);
7729 /* Unfortunately, we cannot just call lookup_name here.
7732 template <int I> int f() {
7734 struct S { void g() { E e = a; } };
7737 When we instantiate f<7>::S::g(), say, lookup_name is not
7738 clever enough to find f<7>::a. */
7740 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7741 /*entering_scope=*/0);
7743 for (v = TYPE_VALUES (enum_type);
7746 if (TREE_PURPOSE (v) == DECL_NAME (t))
7747 return TREE_VALUE (v);
7749 /* We didn't find the name. That should never happen; if
7750 name-lookup found it during preliminary parsing, we
7751 should find it again here during instantiation. */
7757 if (DECL_CONTEXT (t))
7761 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7762 /*entering_scope=*/1);
7763 if (ctx != DECL_CONTEXT (t))
7765 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7768 if (complain & tf_error)
7769 error ("using invalid field %qD", t);
7770 return error_mark_node;
7780 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7781 || local_variable_p (t))
7782 t = tsubst (t, args, complain, in_decl);
7787 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7790 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7791 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7792 args, complain, in_decl);
7793 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7794 return tsubst (t, args, complain, in_decl);
7795 else if (DECL_CLASS_SCOPE_P (t)
7796 && uses_template_parms (DECL_CONTEXT (t)))
7798 /* Template template argument like the following example need
7801 template <template <class> class TT> struct C {};
7802 template <class T> struct D {
7803 template <class U> struct E {};
7808 We are processing the template argument `E' in #1 for
7809 the template instantiation #2. Originally, `E' is a
7810 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7811 have to substitute this with one having context `D<int>'. */
7813 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7814 return lookup_field (context, DECL_NAME(t), 0, false);
7817 /* Ordinary template template argument. */
7821 case REINTERPRET_CAST_EXPR:
7822 case CONST_CAST_EXPR:
7823 case STATIC_CAST_EXPR:
7824 case DYNAMIC_CAST_EXPR:
7827 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7828 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7832 case TRUTH_NOT_EXPR:
7835 case UNARY_PLUS_EXPR: /* Unary + */
7844 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7845 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7852 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7853 name = TREE_OPERAND (t, 1);
7854 if (TREE_CODE (name) == BIT_NOT_EXPR)
7856 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7858 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7860 else if (TREE_CODE (name) == SCOPE_REF
7861 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7863 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7865 name = TREE_OPERAND (name, 1);
7866 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7868 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7869 name = build_nt (SCOPE_REF, base, name);
7871 else if (TREE_CODE (name) == BASELINK)
7872 name = tsubst_baselink (name,
7873 non_reference (TREE_TYPE (object)),
7877 name = tsubst_copy (name, args, complain, in_decl);
7878 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7884 case TRUNC_DIV_EXPR:
7886 case FLOOR_DIV_EXPR:
7887 case ROUND_DIV_EXPR:
7888 case EXACT_DIV_EXPR:
7892 case TRUNC_MOD_EXPR:
7893 case FLOOR_MOD_EXPR:
7894 case TRUTH_ANDIF_EXPR:
7895 case TRUTH_ORIF_EXPR:
7896 case TRUTH_AND_EXPR:
7914 case PREDECREMENT_EXPR:
7915 case PREINCREMENT_EXPR:
7916 case POSTDECREMENT_EXPR:
7917 case POSTINCREMENT_EXPR:
7919 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7920 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7925 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7926 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7927 NULL_TREE, NULL_TREE);
7930 return build_nt (code,
7931 tsubst_copy (TREE_OPERAND (t, 0), args,
7933 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7939 case PSEUDO_DTOR_EXPR:
7942 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7943 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7944 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7945 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7952 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7953 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7954 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7955 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7962 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7963 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7964 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7965 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7969 case TEMPLATE_ID_EXPR:
7971 /* Substituted template arguments */
7972 tree fn = TREE_OPERAND (t, 0);
7973 tree targs = TREE_OPERAND (t, 1);
7975 fn = tsubst_copy (fn, args, complain, in_decl);
7977 targs = tsubst_template_args (targs, args, complain, in_decl);
7979 return lookup_template_function (fn, targs);
7984 tree purpose, value, chain;
7986 if (t == void_list_node)
7989 purpose = TREE_PURPOSE (t);
7991 purpose = tsubst_copy (purpose, args, complain, in_decl);
7992 value = TREE_VALUE (t);
7994 value = tsubst_copy (value, args, complain, in_decl);
7995 chain = TREE_CHAIN (t);
7996 if (chain && chain != void_type_node)
7997 chain = tsubst_copy (chain, args, complain, in_decl);
7998 if (purpose == TREE_PURPOSE (t)
7999 && value == TREE_VALUE (t)
8000 && chain == TREE_CHAIN (t))
8002 return tree_cons (purpose, value, chain);
8009 case TEMPLATE_TYPE_PARM:
8010 case TEMPLATE_TEMPLATE_PARM:
8011 case BOUND_TEMPLATE_TEMPLATE_PARM:
8012 case TEMPLATE_PARM_INDEX:
8014 case REFERENCE_TYPE:
8020 case UNBOUND_CLASS_TEMPLATE:
8023 return tsubst (t, args, complain, in_decl);
8025 case IDENTIFIER_NODE:
8026 if (IDENTIFIER_TYPENAME_P (t))
8028 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8029 return mangle_conv_op_name_for_type (new_type);
8035 /* This is handled by tsubst_copy_and_build. */
8039 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8041 tsubst (TREE_TYPE (t), args, complain, in_decl));
8043 case CLEANUP_POINT_EXPR:
8044 /* We shouldn't have built any of these during initial template
8045 generation. Instead, they should be built during instantiation
8046 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8054 /* Like tsubst_copy for expressions, etc. but also does semantic
8058 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8062 if (t == NULL_TREE || t == error_mark_node)
8065 if (EXPR_HAS_LOCATION (t))
8066 input_location = EXPR_LOCATION (t);
8067 if (STATEMENT_CODE_P (TREE_CODE (t)))
8068 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8070 switch (TREE_CODE (t))
8072 case STATEMENT_LIST:
8074 tree_stmt_iterator i;
8075 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8076 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8080 case CTOR_INITIALIZER:
8081 finish_mem_initializers (tsubst_initializer_list
8082 (TREE_OPERAND (t, 0), args));
8086 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8087 args, complain, in_decl));
8091 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8092 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8093 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8095 finish_expr_stmt (tmp);
8099 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8100 args, complain, in_decl));
8108 decl = DECL_EXPR_DECL (t);
8109 if (TREE_CODE (decl) == LABEL_DECL)
8110 finish_label_decl (DECL_NAME (decl));
8111 else if (TREE_CODE (decl) == USING_DECL)
8113 tree scope = USING_DECL_SCOPE (decl);
8114 tree name = DECL_NAME (decl);
8117 scope = tsubst_expr (scope, args, complain, in_decl);
8118 decl = lookup_qualified_name (scope, name,
8119 /*is_type_p=*/false,
8120 /*complain=*/false);
8121 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8122 qualified_name_lookup_error (scope, name, decl);
8124 do_local_using_decl (decl, scope, name);
8128 init = DECL_INITIAL (decl);
8129 decl = tsubst (decl, args, complain, in_decl);
8130 if (decl != error_mark_node)
8133 DECL_INITIAL (decl) = error_mark_node;
8134 /* By marking the declaration as instantiated, we avoid
8135 trying to instantiate it. Since instantiate_decl can't
8136 handle local variables, and since we've already done
8137 all that needs to be done, that's the right thing to
8139 if (TREE_CODE (decl) == VAR_DECL)
8140 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8141 if (TREE_CODE (decl) == VAR_DECL
8142 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8143 /* Anonymous aggregates are a special case. */
8144 finish_anon_union (decl);
8147 maybe_push_decl (decl);
8148 if (TREE_CODE (decl) == VAR_DECL
8149 && DECL_PRETTY_FUNCTION_P (decl))
8151 /* For __PRETTY_FUNCTION__ we have to adjust the
8153 const char *const name
8154 = cxx_printable_name (current_function_decl, 2);
8155 init = cp_fname_init (name, &TREE_TYPE (decl));
8158 init = tsubst_expr (init, args, complain, in_decl);
8159 cp_finish_decl (decl, init, NULL_TREE, 0);
8164 /* A DECL_EXPR can also be used as an expression, in the condition
8165 clause of an if/for/while construct. */
8170 stmt = begin_for_stmt ();
8171 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8172 finish_for_init_stmt (stmt);
8173 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8174 finish_for_cond (tmp, stmt);
8175 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8176 finish_for_expr (tmp, stmt);
8177 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8178 finish_for_stmt (stmt);
8182 stmt = begin_while_stmt ();
8183 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8184 finish_while_stmt_cond (tmp, stmt);
8185 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8186 finish_while_stmt (stmt);
8190 stmt = begin_do_stmt ();
8191 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8192 finish_do_body (stmt);
8193 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8194 finish_do_stmt (tmp, stmt);
8198 stmt = begin_if_stmt ();
8199 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8200 finish_if_stmt_cond (tmp, stmt);
8201 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8202 finish_then_clause (stmt);
8204 if (ELSE_CLAUSE (t))
8206 begin_else_clause (stmt);
8207 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8208 finish_else_clause (stmt);
8211 finish_if_stmt (stmt);
8215 if (BIND_EXPR_BODY_BLOCK (t))
8216 stmt = begin_function_body ();
8218 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8219 ? BCS_TRY_BLOCK : 0);
8221 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8223 if (BIND_EXPR_BODY_BLOCK (t))
8224 finish_function_body (stmt);
8226 finish_compound_stmt (stmt);
8230 finish_break_stmt ();
8234 finish_continue_stmt ();
8238 stmt = begin_switch_stmt ();
8239 tmp = tsubst_expr (SWITCH_STMT_COND (t), args, complain, in_decl);
8240 finish_switch_cond (tmp, stmt);
8241 tsubst_expr (SWITCH_STMT_BODY (t), args, complain, in_decl);
8242 finish_switch_stmt (stmt);
8245 case CASE_LABEL_EXPR:
8246 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8247 tsubst_expr (CASE_HIGH (t), args, complain,
8252 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8256 tmp = GOTO_DESTINATION (t);
8257 if (TREE_CODE (tmp) != LABEL_DECL)
8258 /* Computed goto's must be tsubst'd into. On the other hand,
8259 non-computed gotos must not be; the identifier in question
8260 will have no binding. */
8261 tmp = tsubst_expr (tmp, args, complain, in_decl);
8263 tmp = DECL_NAME (tmp);
8264 finish_goto_stmt (tmp);
8268 tmp = finish_asm_stmt
8269 (ASM_VOLATILE_P (t),
8270 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8271 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8272 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8273 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8275 tree asm_expr = tmp;
8276 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8277 asm_expr = TREE_OPERAND (asm_expr, 0);
8278 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8285 stmt = begin_try_block ();
8286 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8287 finish_cleanup_try_block (stmt);
8288 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8294 if (FN_TRY_BLOCK_P (t))
8295 stmt = begin_function_try_block ();
8297 stmt = begin_try_block ();
8299 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8301 if (FN_TRY_BLOCK_P (t))
8302 finish_function_try_block (stmt);
8304 finish_try_block (stmt);
8306 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8307 if (FN_TRY_BLOCK_P (t))
8308 finish_function_handler_sequence (stmt);
8310 finish_handler_sequence (stmt);
8318 stmt = begin_handler ();
8319 if (HANDLER_PARMS (t))
8321 decl = HANDLER_PARMS (t);
8322 decl = tsubst (decl, args, complain, in_decl);
8323 /* Prevent instantiate_decl from trying to instantiate
8324 this variable. We've already done all that needs to be
8326 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8330 finish_handler_parms (decl, stmt);
8331 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8332 finish_handler (stmt);
8337 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8341 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8343 return tsubst_copy_and_build (t, args, complain, in_decl,
8344 /*function_p=*/false);
8350 /* T is a postfix-expression that is not being used in a function
8351 call. Return the substituted version of T. */
8354 tsubst_non_call_postfix_expression (tree t, tree args,
8355 tsubst_flags_t complain,
8358 if (TREE_CODE (t) == SCOPE_REF)
8359 t = tsubst_qualified_id (t, args, complain, in_decl,
8360 /*done=*/false, /*address_p=*/false);
8362 t = tsubst_copy_and_build (t, args, complain, in_decl,
8363 /*function_p=*/false);
8368 /* Like tsubst but deals with expressions and performs semantic
8369 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8372 tsubst_copy_and_build (tree t,
8374 tsubst_flags_t complain,
8378 #define RECUR(NODE) \
8379 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8383 if (t == NULL_TREE || t == error_mark_node)
8386 switch (TREE_CODE (t))
8391 case IDENTIFIER_NODE:
8395 tree qualifying_class;
8396 bool non_integral_constant_expression_p;
8397 const char *error_msg;
8399 if (IDENTIFIER_TYPENAME_P (t))
8401 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8402 t = mangle_conv_op_name_for_type (new_type);
8405 /* Look up the name. */
8406 decl = lookup_name (t, 0);
8408 /* By convention, expressions use ERROR_MARK_NODE to indicate
8409 failure, not NULL_TREE. */
8410 if (decl == NULL_TREE)
8411 decl = error_mark_node;
8413 decl = finish_id_expression (t, decl, NULL_TREE,
8416 /*integral_constant_expression_p=*/false,
8417 /*allow_non_integral_constant_expression_p=*/false,
8418 &non_integral_constant_expression_p,
8422 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8423 decl = unqualified_name_lookup_error (decl);
8427 case TEMPLATE_ID_EXPR:
8430 tree template = RECUR (TREE_OPERAND (t, 0));
8431 tree targs = TREE_OPERAND (t, 1);
8434 targs = tsubst_template_args (targs, args, complain, in_decl);
8436 if (TREE_CODE (template) == COMPONENT_REF)
8438 object = TREE_OPERAND (template, 0);
8439 template = TREE_OPERAND (template, 1);
8443 template = lookup_template_function (template, targs);
8446 return build3 (COMPONENT_REF, TREE_TYPE (template),
8447 object, template, NULL_TREE);
8454 tree r = RECUR (TREE_OPERAND (t, 0));
8456 if (REFERENCE_REF_P (t))
8458 /* A type conversion to reference type will be enclosed in
8459 such an indirect ref, but the substitution of the cast
8460 will have also added such an indirect ref. */
8461 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8462 r = convert_from_reference (r);
8465 r = build_x_indirect_ref (r, "unary *");
8471 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8472 RECUR (TREE_OPERAND (t, 0)));
8475 return build_functional_cast
8476 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8477 RECUR (TREE_OPERAND (t, 0)));
8479 case REINTERPRET_CAST_EXPR:
8480 return build_reinterpret_cast
8481 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8482 RECUR (TREE_OPERAND (t, 0)));
8484 case CONST_CAST_EXPR:
8485 return build_const_cast
8486 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8487 RECUR (TREE_OPERAND (t, 0)));
8489 case DYNAMIC_CAST_EXPR:
8490 return build_dynamic_cast
8491 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8492 RECUR (TREE_OPERAND (t, 0)));
8494 case STATIC_CAST_EXPR:
8495 return build_static_cast
8496 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8497 RECUR (TREE_OPERAND (t, 0)));
8499 case POSTDECREMENT_EXPR:
8500 case POSTINCREMENT_EXPR:
8501 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8502 args, complain, in_decl);
8503 return build_x_unary_op (TREE_CODE (t), op1);
8505 case PREDECREMENT_EXPR:
8506 case PREINCREMENT_EXPR:
8510 case TRUTH_NOT_EXPR:
8511 case UNARY_PLUS_EXPR: /* Unary + */
8514 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8517 op1 = TREE_OPERAND (t, 0);
8518 if (TREE_CODE (op1) == SCOPE_REF)
8519 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8520 /*done=*/true, /*address_p=*/true);
8522 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8524 if (TREE_CODE (op1) == LABEL_DECL)
8525 return finish_label_address_expr (DECL_NAME (op1));
8526 return build_x_unary_op (ADDR_EXPR, op1);
8531 case TRUNC_DIV_EXPR:
8533 case FLOOR_DIV_EXPR:
8534 case ROUND_DIV_EXPR:
8535 case EXACT_DIV_EXPR:
8539 case TRUNC_MOD_EXPR:
8540 case FLOOR_MOD_EXPR:
8541 case TRUTH_ANDIF_EXPR:
8542 case TRUTH_ORIF_EXPR:
8543 case TRUTH_AND_EXPR:
8559 return build_x_binary_op
8561 RECUR (TREE_OPERAND (t, 0)),
8562 RECUR (TREE_OPERAND (t, 1)),
8563 /*overloaded_p=*/NULL);
8566 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8567 /*address_p=*/false);
8569 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8570 args, complain, in_decl);
8571 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8572 /*overloaded_p=*/NULL);
8576 op1 = TREE_OPERAND (t, 0);
8579 /* When there are no ARGS, we are trying to evaluate a
8580 non-dependent expression from the parser. Trying to do
8581 the substitutions may not work. */
8583 op1 = TREE_TYPE (op1);
8592 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8594 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8598 tree r = build_x_modify_expr
8599 (RECUR (TREE_OPERAND (t, 0)),
8600 TREE_CODE (TREE_OPERAND (t, 1)),
8601 RECUR (TREE_OPERAND (t, 2)));
8602 /* TREE_NO_WARNING must be set if either the expression was
8603 parenthesized or it uses an operator such as >>= rather
8604 than plain assignment. In the former case, it was already
8605 set and must be copied. In the latter case,
8606 build_x_modify_expr sets it and it must not be reset
8608 if (TREE_NO_WARNING (t))
8609 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8614 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8615 args, complain, in_decl);
8616 /* Remember that there was a reference to this entity. */
8619 return build_x_arrow (op1);
8623 (RECUR (TREE_OPERAND (t, 0)),
8624 RECUR (TREE_OPERAND (t, 1)),
8625 RECUR (TREE_OPERAND (t, 2)),
8626 RECUR (TREE_OPERAND (t, 3)),
8627 NEW_EXPR_USE_GLOBAL (t));
8630 return delete_sanity
8631 (RECUR (TREE_OPERAND (t, 0)),
8632 RECUR (TREE_OPERAND (t, 1)),
8633 DELETE_EXPR_USE_VEC (t),
8634 DELETE_EXPR_USE_GLOBAL (t));
8637 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8638 RECUR (TREE_OPERAND (t, 1)));
8647 function = TREE_OPERAND (t, 0);
8648 /* When we parsed the expression, we determined whether or
8649 not Koenig lookup should be performed. */
8650 koenig_p = KOENIG_LOOKUP_P (t);
8651 if (TREE_CODE (function) == SCOPE_REF)
8654 function = tsubst_qualified_id (function, args, complain, in_decl,
8656 /*address_p=*/false);
8660 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8661 && (TREE_CODE (TREE_OPERAND (function, 1))
8663 function = tsubst_copy_and_build (function, args, complain,
8666 if (BASELINK_P (function))
8670 call_args = RECUR (TREE_OPERAND (t, 1));
8672 /* We do not perform argument-dependent lookup if normal
8673 lookup finds a non-function, in accordance with the
8674 expected resolution of DR 218. */
8676 && ((is_overloaded_fn (function)
8677 /* If lookup found a member function, the Koenig lookup is
8678 not appropriate, even if an unqualified-name was used
8679 to denote the function. */
8680 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8681 || TREE_CODE (function) == IDENTIFIER_NODE))
8682 function = perform_koenig_lookup (function, call_args);
8684 if (TREE_CODE (function) == IDENTIFIER_NODE)
8686 unqualified_name_lookup_error (function);
8687 return error_mark_node;
8690 /* Remember that there was a reference to this entity. */
8691 if (DECL_P (function))
8692 mark_used (function);
8694 if (TREE_CODE (function) == OFFSET_REF)
8695 return build_offset_ref_call_from_tree (function, call_args);
8696 if (TREE_CODE (function) == COMPONENT_REF)
8698 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8699 return finish_call_expr (function, call_args,
8700 /*disallow_virtual=*/false,
8701 /*koenig_p=*/false);
8703 return (build_new_method_call
8704 (TREE_OPERAND (function, 0),
8705 TREE_OPERAND (function, 1),
8706 call_args, NULL_TREE,
8707 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8709 return finish_call_expr (function, call_args,
8710 /*disallow_virtual=*/qualified_p,
8715 return build_x_conditional_expr
8716 (RECUR (TREE_OPERAND (t, 0)),
8717 RECUR (TREE_OPERAND (t, 1)),
8718 RECUR (TREE_OPERAND (t, 2)));
8720 case PSEUDO_DTOR_EXPR:
8721 return finish_pseudo_destructor_expr
8722 (RECUR (TREE_OPERAND (t, 0)),
8723 RECUR (TREE_OPERAND (t, 1)),
8724 RECUR (TREE_OPERAND (t, 2)));
8728 tree purpose, value, chain;
8730 if (t == void_list_node)
8733 purpose = TREE_PURPOSE (t);
8735 purpose = RECUR (purpose);
8736 value = TREE_VALUE (t);
8738 value = RECUR (value);
8739 chain = TREE_CHAIN (t);
8740 if (chain && chain != void_type_node)
8741 chain = RECUR (chain);
8742 if (purpose == TREE_PURPOSE (t)
8743 && value == TREE_VALUE (t)
8744 && chain == TREE_CHAIN (t))
8746 return tree_cons (purpose, value, chain);
8754 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8755 args, complain, in_decl);
8756 /* Remember that there was a reference to this entity. */
8757 if (DECL_P (object))
8760 member = TREE_OPERAND (t, 1);
8761 if (BASELINK_P (member))
8762 member = tsubst_baselink (member,
8763 non_reference (TREE_TYPE (object)),
8764 args, complain, in_decl);
8766 member = tsubst_copy (member, args, complain, in_decl);
8768 if (member == error_mark_node)
8769 return error_mark_node;
8770 else if (!CLASS_TYPE_P (TREE_TYPE (object)))
8772 if (TREE_CODE (member) == BIT_NOT_EXPR)
8773 return finish_pseudo_destructor_expr (object,
8775 TREE_TYPE (object));
8776 else if (TREE_CODE (member) == SCOPE_REF
8777 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8778 return finish_pseudo_destructor_expr (object,
8780 TREE_TYPE (object));
8782 else if (TREE_CODE (member) == SCOPE_REF
8783 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8788 /* Lookup the template functions now that we know what the
8790 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8791 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8792 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8793 /*is_type_p=*/false,
8794 /*complain=*/false);
8795 if (BASELINK_P (member))
8797 BASELINK_FUNCTIONS (member)
8798 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8800 member = (adjust_result_of_qualified_name_lookup
8801 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8802 TREE_TYPE (object)));
8806 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8808 return error_mark_node;
8811 else if (TREE_CODE (member) == SCOPE_REF
8812 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8813 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8815 if (complain & tf_error)
8817 if (TYPE_P (TREE_OPERAND (member, 0)))
8818 error ("%qT is not a class or namespace",
8819 TREE_OPERAND (member, 0));
8821 error ("%qD is not a class or namespace",
8822 TREE_OPERAND (member, 0));
8824 return error_mark_node;
8826 else if (TREE_CODE (member) == FIELD_DECL)
8827 return finish_non_static_data_member (member, object, NULL_TREE);
8829 return finish_class_member_access_expr (object, member);
8834 (RECUR (TREE_OPERAND (t, 0)));
8838 VEC(constructor_elt,gc) *n;
8839 constructor_elt *ce;
8840 unsigned HOST_WIDE_INT idx;
8842 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8843 bool process_index_p;
8845 /* digest_init will do the wrong thing if we let it. */
8846 if (type && TYPE_PTRMEMFUNC_P (type))
8849 /* We do not want to process the index of aggregate
8850 initializers as they are identifier nodes which will be
8851 looked up by digest_init. */
8852 process_index_p = !(type && IS_AGGR_TYPE (type));
8854 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
8855 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
8857 if (ce->index && process_index_p)
8858 ce->index = RECUR (ce->index);
8859 ce->value = RECUR (ce->value);
8862 r = build_constructor (NULL_TREE, n);
8863 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8866 return digest_init (type, r);
8872 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8873 if (TYPE_P (operand_0))
8874 return get_typeid (operand_0);
8875 return build_typeid (operand_0);
8885 tree r = tsubst_copy (t, args, complain, in_decl);
8887 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
8888 /* If the original type was a reference, we'll be wrapped in
8889 the appropriate INDIRECT_REF. */
8890 r = convert_from_reference (r);
8895 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8896 tsubst_copy (TREE_TYPE (t), args, complain,
8900 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8904 tree old_stmt_expr = cur_stmt_expr;
8905 tree stmt_expr = begin_stmt_expr ();
8907 cur_stmt_expr = stmt_expr;
8908 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8909 stmt_expr = finish_stmt_expr (stmt_expr, false);
8910 cur_stmt_expr = old_stmt_expr;
8916 t = tsubst_copy (t, args, complain, in_decl);
8917 /* As in finish_id_expression, we resolve enumeration constants
8918 to their underlying values. */
8919 if (TREE_CODE (t) == CONST_DECL)
8920 return DECL_INITIAL (t);
8924 /* Handle Objective-C++ constructs, if appropriate. */
8927 = objcp_tsubst_copy_and_build (t, args, complain,
8928 in_decl, /*function_p=*/false);
8932 return tsubst_copy (t, args, complain, in_decl);
8938 /* Verify that the instantiated ARGS are valid. For type arguments,
8939 make sure that the type's linkage is ok. For non-type arguments,
8940 make sure they are constants if they are integral or enumerations.
8941 Emit an error under control of COMPLAIN, and return TRUE on error. */
8944 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8946 int ix, len = DECL_NTPARMS (tmpl);
8947 bool result = false;
8948 bool error_p = complain & tf_error;
8950 for (ix = 0; ix != len; ix++)
8952 tree t = TREE_VEC_ELT (args, ix);
8956 /* [basic.link]: A name with no linkage (notably, the name
8957 of a class or enumeration declared in a local scope)
8958 shall not be used to declare an entity with linkage.
8959 This implies that names with no linkage cannot be used as
8960 template arguments. */
8961 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8965 if (TYPE_ANONYMOUS_P (nt))
8966 error ("%qT is/uses anonymous type", t);
8968 error ("%qT uses local type %qT", t, nt);
8972 /* In order to avoid all sorts of complications, we do not
8973 allow variably-modified types as template arguments. */
8974 else if (variably_modified_type_p (t, NULL_TREE))
8976 if (complain & tf_error)
8977 error ("%qT is a variably modified type", t);
8981 /* A non-type argument of integral or enumerated type must be a
8983 else if (TREE_TYPE (t)
8984 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8985 && !TREE_CONSTANT (t))
8987 if (complain & tf_error)
8988 error ("integral expression %qE is not constant", t);
8992 if (result && error_p)
8993 error (" trying to instantiate %qD", tmpl);
8997 /* Instantiate the indicated variable or function template TMPL with
8998 the template arguments in TARG_PTR. */
9001 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
9007 if (tmpl == error_mark_node)
9008 return error_mark_node;
9010 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
9012 /* If this function is a clone, handle it specially. */
9013 if (DECL_CLONED_FUNCTION_P (tmpl))
9018 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
9020 if (spec == error_mark_node)
9021 return error_mark_node;
9023 /* Look for the clone. */
9024 FOR_EACH_CLONE (clone, spec)
9025 if (DECL_NAME (clone) == DECL_NAME (tmpl))
9027 /* We should always have found the clone by now. */
9032 /* Check to see if we already have this specialization. */
9033 spec = retrieve_specialization (tmpl, targ_ptr,
9034 /*class_specializations_p=*/false);
9035 if (spec != NULL_TREE)
9038 gen_tmpl = most_general_template (tmpl);
9039 if (tmpl != gen_tmpl)
9041 /* The TMPL is a partial instantiation. To get a full set of
9042 arguments we must add the arguments used to perform the
9043 partial instantiation. */
9044 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9047 /* Check to see if we already have this specialization. */
9048 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9049 /*class_specializations_p=*/false);
9050 if (spec != NULL_TREE)
9054 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9056 return error_mark_node;
9058 /* We are building a FUNCTION_DECL, during which the access of its
9059 parameters and return types have to be checked. However this
9060 FUNCTION_DECL which is the desired context for access checking
9061 is not built yet. We solve this chicken-and-egg problem by
9062 deferring all checks until we have the FUNCTION_DECL. */
9063 push_deferring_access_checks (dk_deferred);
9065 /* Substitute template parameters. */
9066 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9067 targ_ptr, complain, gen_tmpl);
9069 /* Now we know the specialization, compute access previously
9071 push_access_scope (fndecl);
9072 perform_deferred_access_checks ();
9073 pop_access_scope (fndecl);
9074 pop_deferring_access_checks ();
9076 /* The DECL_TI_TEMPLATE should always be the immediate parent
9077 template, not the most general template. */
9078 DECL_TI_TEMPLATE (fndecl) = tmpl;
9080 /* If we've just instantiated the main entry point for a function,
9081 instantiate all the alternate entry points as well. We do this
9082 by cloning the instantiation of the main entry point, not by
9083 instantiating the template clones. */
9084 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9085 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9090 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9091 arguments that are being used when calling it. TARGS is a vector
9092 into which the deduced template arguments are placed.
9094 Return zero for success, 2 for an incomplete match that doesn't resolve
9095 all the types, and 1 for complete failure. An error message will be
9096 printed only for an incomplete match.
9098 If FN is a conversion operator, or we are trying to produce a specific
9099 specialization, RETURN_TYPE is the return type desired.
9101 The EXPLICIT_TARGS are explicit template arguments provided via a
9104 The parameter STRICT is one of:
9107 We are deducing arguments for a function call, as in
9111 We are deducing arguments for a conversion function, as in
9115 We are deducing arguments when doing an explicit instantiation
9116 as in [temp.explicit], when determining an explicit specialization
9117 as in [temp.expl.spec], or when taking the address of a function
9118 template, as in [temp.deduct.funcaddr]. */
9121 fn_type_unification (tree fn,
9122 tree explicit_targs,
9126 unification_kind_t strict,
9133 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9135 fntype = TREE_TYPE (fn);
9140 The specified template arguments must match the template
9141 parameters in kind (i.e., type, nontype, template), and there
9142 must not be more arguments than there are parameters;
9143 otherwise type deduction fails.
9145 Nontype arguments must match the types of the corresponding
9146 nontype template parameters, or must be convertible to the
9147 types of the corresponding nontype parameters as specified in
9148 _temp.arg.nontype_, otherwise type deduction fails.
9150 All references in the function type of the function template
9151 to the corresponding template parameters are replaced by the
9152 specified template argument values. If a substitution in a
9153 template parameter or in the function type of the function
9154 template results in an invalid type, type deduction fails. */
9156 tree converted_args;
9159 if (explicit_targs == error_mark_node)
9163 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9164 explicit_targs, NULL_TREE, tf_none,
9165 /*require_all_arguments=*/0));
9166 if (converted_args == error_mark_node)
9169 /* Substitute the explicit args into the function type. This is
9170 necessary so that, for instance, explicitly declared function
9171 arguments can match null pointed constants. If we were given
9172 an incomplete set of explicit args, we must not do semantic
9173 processing during substitution as we could create partial
9175 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9176 processing_template_decl += incomplete;
9177 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9178 processing_template_decl -= incomplete;
9180 if (fntype == error_mark_node)
9183 /* Place the explicitly specified arguments in TARGS. */
9184 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9185 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9188 parms = TYPE_ARG_TYPES (fntype);
9189 /* Never do unification on the 'this' parameter. */
9190 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9191 parms = TREE_CHAIN (parms);
9195 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9196 args = tree_cons (NULL_TREE, return_type, args);
9199 /* We allow incomplete unification without an error message here
9200 because the standard doesn't seem to explicitly prohibit it. Our
9201 callers must be ready to deal with unification failures in any
9203 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9204 targs, parms, args, /*subr=*/0,
9208 /* All is well so far. Now, check:
9212 When all template arguments have been deduced, all uses of
9213 template parameters in nondeduced contexts are replaced with
9214 the corresponding deduced argument values. If the
9215 substitution results in an invalid type, as described above,
9216 type deduction fails. */
9217 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9224 /* Adjust types before performing type deduction, as described in
9225 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9226 sections are symmetric. PARM is the type of a function parameter
9227 or the return type of the conversion function. ARG is the type of
9228 the argument passed to the call, or the type of the value
9229 initialized with the result of the conversion function. */
9232 maybe_adjust_types_for_deduction (unification_kind_t strict,
9245 /* Swap PARM and ARG throughout the remainder of this
9246 function; the handling is precisely symmetric since PARM
9247 will initialize ARG rather than vice versa. */
9255 /* There is nothing to do in this case. */
9262 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9264 /* [temp.deduct.call]
9266 If P is not a reference type:
9268 --If A is an array type, the pointer type produced by the
9269 array-to-pointer standard conversion (_conv.array_) is
9270 used in place of A for type deduction; otherwise,
9272 --If A is a function type, the pointer type produced by
9273 the function-to-pointer standard conversion
9274 (_conv.func_) is used in place of A for type deduction;
9277 --If A is a cv-qualified type, the top level
9278 cv-qualifiers of A's type are ignored for type
9280 if (TREE_CODE (*arg) == ARRAY_TYPE)
9281 *arg = build_pointer_type (TREE_TYPE (*arg));
9282 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9283 *arg = build_pointer_type (*arg);
9285 *arg = TYPE_MAIN_VARIANT (*arg);
9288 /* [temp.deduct.call]
9290 If P is a cv-qualified type, the top level cv-qualifiers
9291 of P's type are ignored for type deduction. If P is a
9292 reference type, the type referred to by P is used for
9294 *parm = TYPE_MAIN_VARIANT (*parm);
9295 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9297 *parm = TREE_TYPE (*parm);
9298 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9301 /* DR 322. For conversion deduction, remove a reference type on parm
9302 too (which has been swapped into ARG). */
9303 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9304 *arg = TREE_TYPE (*arg);
9309 /* Most parms like fn_type_unification.
9311 If SUBR is 1, we're being called recursively (to unify the
9312 arguments of a function or method parameter of a function
9316 type_unification_real (tree tparms,
9321 unification_kind_t strict,
9326 int ntparms = TREE_VEC_LENGTH (tparms);
9328 int saw_undeduced = 0;
9331 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9332 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9333 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9334 gcc_assert (ntparms > 0);
9339 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9340 | UNIFY_ALLOW_DERIVED);
9344 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9348 sub_strict = UNIFY_ALLOW_NONE;
9359 while (parms && parms != void_list_node
9360 && args && args != void_list_node)
9362 parm = TREE_VALUE (parms);
9363 parms = TREE_CHAIN (parms);
9364 arg = TREE_VALUE (args);
9365 args = TREE_CHAIN (args);
9367 if (arg == error_mark_node)
9369 if (arg == unknown_type_node)
9370 /* We can't deduce anything from this, but we might get all the
9371 template args from other function args. */
9374 /* Conversions will be performed on a function argument that
9375 corresponds with a function parameter that contains only
9376 non-deducible template parameters and explicitly specified
9377 template parameters. */
9378 if (!uses_template_parms (parm))
9383 type = TREE_TYPE (arg);
9387 if (same_type_p (parm, type))
9389 if (strict != DEDUCE_EXACT
9390 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
9399 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9400 if (type_unknown_p (arg))
9402 /* [temp.deduct.type] A template-argument can be deduced from
9403 a pointer to function or pointer to member function
9404 argument if the set of overloaded functions does not
9405 contain function templates and at most one of a set of
9406 overloaded functions provides a unique match. */
9408 if (resolve_overloaded_unification
9409 (tparms, targs, parm, arg, strict, sub_strict)
9414 arg = TREE_TYPE (arg);
9415 if (arg == error_mark_node)
9420 int arg_strict = sub_strict;
9423 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9425 if (unify (tparms, targs, parm, arg, arg_strict))
9430 /* Fail if we've reached the end of the parm list, and more args
9431 are present, and the parm list isn't variadic. */
9432 if (args && args != void_list_node && parms == void_list_node)
9434 /* Fail if parms are left and they don't have default values. */
9435 if (parms && parms != void_list_node
9436 && TREE_PURPOSE (parms) == NULL_TREE)
9440 for (i = 0; i < ntparms; i++)
9441 if (!TREE_VEC_ELT (targs, i))
9443 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9445 /* If this is an undeduced nontype parameter that depends on
9446 a type parameter, try another pass; its type may have been
9447 deduced from a later argument than the one from which
9448 this parameter can be deduced. */
9449 if (TREE_CODE (tparm) == PARM_DECL
9450 && uses_template_parms (TREE_TYPE (tparm))
9451 && !saw_undeduced++)
9460 /* Subroutine of type_unification_real. Args are like the variables at the
9461 call site. ARG is an overloaded function (or template-id); we try
9462 deducing template args from each of the overloads, and if only one
9463 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9466 resolve_overloaded_unification (tree tparms,
9470 unification_kind_t strict,
9473 tree tempargs = copy_node (targs);
9477 if (TREE_CODE (arg) == ADDR_EXPR)
9479 arg = TREE_OPERAND (arg, 0);
9485 if (TREE_CODE (arg) == COMPONENT_REF)
9486 /* Handle `&x' where `x' is some static or non-static member
9488 arg = TREE_OPERAND (arg, 1);
9490 if (TREE_CODE (arg) == OFFSET_REF)
9491 arg = TREE_OPERAND (arg, 1);
9493 /* Strip baselink information. */
9494 if (BASELINK_P (arg))
9495 arg = BASELINK_FUNCTIONS (arg);
9497 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9499 /* If we got some explicit template args, we need to plug them into
9500 the affected templates before we try to unify, in case the
9501 explicit args will completely resolve the templates in question. */
9503 tree expl_subargs = TREE_OPERAND (arg, 1);
9504 arg = TREE_OPERAND (arg, 0);
9506 for (; arg; arg = OVL_NEXT (arg))
9508 tree fn = OVL_CURRENT (arg);
9511 if (TREE_CODE (fn) != TEMPLATE_DECL)
9514 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
9515 expl_subargs, /*check_ret=*/false);
9518 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9519 good += try_one_overload (tparms, targs, tempargs, parm,
9520 elem, strict, sub_strict, addr_p);
9526 gcc_assert (TREE_CODE (arg) == OVERLOAD
9527 || TREE_CODE (arg) == FUNCTION_DECL);
9529 for (; arg; arg = OVL_NEXT (arg))
9530 good += try_one_overload (tparms, targs, tempargs, parm,
9531 TREE_TYPE (OVL_CURRENT (arg)),
9532 strict, sub_strict, addr_p);
9535 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9536 to function or pointer to member function argument if the set of
9537 overloaded functions does not contain function templates and at most
9538 one of a set of overloaded functions provides a unique match.
9540 So if we found multiple possibilities, we return success but don't
9545 int i = TREE_VEC_LENGTH (targs);
9547 if (TREE_VEC_ELT (tempargs, i))
9548 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9556 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9557 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9558 different overloads deduce different arguments for a given parm.
9559 ADDR_P is true if the expression for which deduction is being
9560 performed was of the form "& fn" rather than simply "fn".
9562 Returns 1 on success. */
9565 try_one_overload (tree tparms,
9570 unification_kind_t strict,
9578 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9579 to function or pointer to member function argument if the set of
9580 overloaded functions does not contain function templates and at most
9581 one of a set of overloaded functions provides a unique match.
9583 So if this is a template, just return success. */
9585 if (uses_template_parms (arg))
9588 if (TREE_CODE (arg) == METHOD_TYPE)
9589 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9591 arg = build_pointer_type (arg);
9593 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9595 /* We don't copy orig_targs for this because if we have already deduced
9596 some template args from previous args, unify would complain when we
9597 try to deduce a template parameter for the same argument, even though
9598 there isn't really a conflict. */
9599 nargs = TREE_VEC_LENGTH (targs);
9600 tempargs = make_tree_vec (nargs);
9602 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9605 /* First make sure we didn't deduce anything that conflicts with
9606 explicitly specified args. */
9607 for (i = nargs; i--; )
9609 tree elt = TREE_VEC_ELT (tempargs, i);
9610 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9614 else if (uses_template_parms (elt))
9615 /* Since we're unifying against ourselves, we will fill in
9616 template args used in the function parm list with our own
9617 template parms. Discard them. */
9618 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9619 else if (oldelt && !template_args_equal (oldelt, elt))
9623 for (i = nargs; i--; )
9625 tree elt = TREE_VEC_ELT (tempargs, i);
9628 TREE_VEC_ELT (targs, i) = elt;
9634 /* Verify that nondeduce template argument agrees with the type
9635 obtained from argument deduction. Return nonzero if the
9640 struct A { typedef int X; };
9641 template <class T, class U> struct C {};
9642 template <class T> struct C<T, typename T::X> {};
9644 Then with the instantiation `C<A, int>', we can deduce that
9645 `T' is `A' but unify () does not check whether `typename T::X'
9646 is `int'. This function ensure that they agree.
9648 TARGS, PARMS are the same as the arguments of unify.
9649 ARGS contains template arguments from all levels. */
9652 verify_class_unification (tree targs, tree parms, tree args)
9654 parms = tsubst (parms, add_outermost_template_args (args, targs),
9655 tf_none, NULL_TREE);
9656 if (parms == error_mark_node)
9659 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9662 /* PARM is a template class (perhaps with unbound template
9663 parameters). ARG is a fully instantiated type. If ARG can be
9664 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9665 TARGS are as for unify. */
9668 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9672 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9673 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9674 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9677 /* We need to make a new template argument vector for the call to
9678 unify. If we used TARGS, we'd clutter it up with the result of
9679 the attempted unification, even if this class didn't work out.
9680 We also don't want to commit ourselves to all the unifications
9681 we've already done, since unification is supposed to be done on
9682 an argument-by-argument basis. In other words, consider the
9683 following pathological case:
9685 template <int I, int J, int K>
9688 template <int I, int J>
9689 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9691 template <int I, int J, int K>
9692 void f(S<I, J, K>, S<I, I, I>);
9701 Now, by the time we consider the unification involving `s2', we
9702 already know that we must have `f<0, 0, 0>'. But, even though
9703 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9704 because there are two ways to unify base classes of S<0, 1, 2>
9705 with S<I, I, I>. If we kept the already deduced knowledge, we
9706 would reject the possibility I=1. */
9707 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9709 /* If unification failed, we're done. */
9710 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9711 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9717 /* Given a template type PARM and a class type ARG, find the unique
9718 base type in ARG that is an instance of PARM. We do not examine
9719 ARG itself; only its base-classes. If there is not exactly one
9720 appropriate base class, return NULL_TREE. PARM may be the type of
9721 a partial specialization, as well as a plain template type. Used
9725 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9727 tree rval = NULL_TREE;
9730 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9732 binfo = TYPE_BINFO (complete_type (arg));
9734 /* The type could not be completed. */
9737 /* Walk in inheritance graph order. The search order is not
9738 important, and this avoids multiple walks of virtual bases. */
9739 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9741 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9745 /* If there is more than one satisfactory baseclass, then:
9749 If they yield more than one possible deduced A, the type
9753 if (rval && !same_type_p (r, rval))
9763 /* Returns the level of DECL, which declares a template parameter. */
9766 template_decl_level (tree decl)
9768 switch (TREE_CODE (decl))
9772 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9775 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9783 /* Decide whether ARG can be unified with PARM, considering only the
9784 cv-qualifiers of each type, given STRICT as documented for unify.
9785 Returns nonzero iff the unification is OK on that basis. */
9788 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9790 int arg_quals = cp_type_quals (arg);
9791 int parm_quals = cp_type_quals (parm);
9793 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9794 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9796 /* Although a CVR qualifier is ignored when being applied to a
9797 substituted template parameter ([8.3.2]/1 for example), that
9798 does not apply during deduction [14.8.2.4]/1, (even though
9799 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9800 this). Except when we're allowing additional CV qualifiers
9801 at the outer level [14.8.2.1]/3,1st bullet. */
9802 if ((TREE_CODE (arg) == REFERENCE_TYPE
9803 || TREE_CODE (arg) == FUNCTION_TYPE
9804 || TREE_CODE (arg) == METHOD_TYPE)
9805 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9808 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9809 && (parm_quals & TYPE_QUAL_RESTRICT))
9813 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9814 && (arg_quals & parm_quals) != parm_quals)
9817 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9818 && (parm_quals & arg_quals) != arg_quals)
9824 /* Takes parameters as for type_unification. Returns 0 if the
9825 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9826 bitwise or of the following flags:
9829 Require an exact match between PARM and ARG.
9830 UNIFY_ALLOW_MORE_CV_QUAL:
9831 Allow the deduced ARG to be more cv-qualified (by qualification
9832 conversion) than ARG.
9833 UNIFY_ALLOW_LESS_CV_QUAL:
9834 Allow the deduced ARG to be less cv-qualified than ARG.
9835 UNIFY_ALLOW_DERIVED:
9836 Allow the deduced ARG to be a template base class of ARG,
9837 or a pointer to a template base class of the type pointed to by
9839 UNIFY_ALLOW_INTEGER:
9840 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9841 case for more information.
9842 UNIFY_ALLOW_OUTER_LEVEL:
9843 This is the outermost level of a deduction. Used to determine validity
9844 of qualification conversions. A valid qualification conversion must
9845 have const qualified pointers leading up to the inner type which
9846 requires additional CV quals, except at the outer level, where const
9847 is not required [conv.qual]. It would be normal to set this flag in
9848 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9849 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9850 This is the outermost level of a deduction, and PARM can be more CV
9851 qualified at this point.
9852 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9853 This is the outermost level of a deduction, and PARM can be less CV
9854 qualified at this point. */
9857 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9862 int strict_in = strict;
9864 /* I don't think this will do the right thing with respect to types.
9865 But the only case I've seen it in so far has been array bounds, where
9866 signedness is the only information lost, and I think that will be
9868 while (TREE_CODE (parm) == NOP_EXPR)
9869 parm = TREE_OPERAND (parm, 0);
9871 if (arg == error_mark_node)
9873 if (arg == unknown_type_node)
9874 /* We can't deduce anything from this, but we might get all the
9875 template args from other function args. */
9878 /* If PARM uses template parameters, then we can't bail out here,
9879 even if ARG == PARM, since we won't record unifications for the
9880 template parameters. We might need them if we're trying to
9881 figure out which of two things is more specialized. */
9882 if (arg == parm && !uses_template_parms (parm))
9885 /* Immediately reject some pairs that won't unify because of
9886 cv-qualification mismatches. */
9887 if (TREE_CODE (arg) == TREE_CODE (parm)
9889 /* It is the elements of the array which hold the cv quals of an array
9890 type, and the elements might be template type parms. We'll check
9892 && TREE_CODE (arg) != ARRAY_TYPE
9893 /* We check the cv-qualifiers when unifying with template type
9894 parameters below. We want to allow ARG `const T' to unify with
9895 PARM `T' for example, when computing which of two templates
9896 is more specialized, for example. */
9897 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9898 && !check_cv_quals_for_unify (strict_in, arg, parm))
9901 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9902 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9903 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9904 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9905 strict &= ~UNIFY_ALLOW_DERIVED;
9906 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9907 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9909 switch (TREE_CODE (parm))
9913 case UNBOUND_CLASS_TEMPLATE:
9914 /* In a type which contains a nested-name-specifier, template
9915 argument values cannot be deduced for template parameters used
9916 within the nested-name-specifier. */
9919 case TEMPLATE_TYPE_PARM:
9920 case TEMPLATE_TEMPLATE_PARM:
9921 case BOUND_TEMPLATE_TEMPLATE_PARM:
9922 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9924 if (TEMPLATE_TYPE_LEVEL (parm)
9925 != template_decl_level (tparm))
9926 /* The PARM is not one we're trying to unify. Just check
9927 to see if it matches ARG. */
9928 return (TREE_CODE (arg) == TREE_CODE (parm)
9929 && same_type_p (parm, arg)) ? 0 : 1;
9930 idx = TEMPLATE_TYPE_IDX (parm);
9931 targ = TREE_VEC_ELT (targs, idx);
9932 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9934 /* Check for mixed types and values. */
9935 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9936 && TREE_CODE (tparm) != TYPE_DECL)
9937 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9938 && TREE_CODE (tparm) != TEMPLATE_DECL))
9941 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9943 /* ARG must be constructed from a template class or a template
9944 template parameter. */
9945 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9946 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9950 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9951 tree parmvec = TYPE_TI_ARGS (parm);
9952 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9954 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9957 /* The parameter and argument roles have to be switched here
9958 in order to handle default arguments properly. For example,
9959 template<template <class> class TT> void f(TT<int>)
9960 should be able to accept vector<int> which comes from
9961 template <class T, class Allocator = allocator>
9964 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9968 /* Deduce arguments T, i from TT<T> or TT<i>.
9969 We check each element of PARMVEC and ARGVEC individually
9970 rather than the whole TREE_VEC since they can have
9971 different number of elements. */
9973 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9975 if (unify (tparms, targs,
9976 TREE_VEC_ELT (parmvec, i),
9977 TREE_VEC_ELT (argvec, i),
9982 arg = TYPE_TI_TEMPLATE (arg);
9984 /* Fall through to deduce template name. */
9987 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9988 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9990 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
9992 /* Simple cases: Value already set, does match or doesn't. */
9993 if (targ != NULL_TREE && template_args_equal (targ, arg))
10000 /* If PARM is `const T' and ARG is only `int', we don't have
10001 a match unless we are allowing additional qualification.
10002 If ARG is `const int' and PARM is just `T' that's OK;
10003 that binds `const int' to `T'. */
10004 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10008 /* Consider the case where ARG is `const volatile int' and
10009 PARM is `const T'. Then, T should be `volatile int'. */
10010 arg = cp_build_qualified_type_real
10011 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10012 if (arg == error_mark_node)
10015 /* Simple cases: Value already set, does match or doesn't. */
10016 if (targ != NULL_TREE && same_type_p (targ, arg))
10021 /* Make sure that ARG is not a variable-sized array. (Note
10022 that were talking about variable-sized arrays (like
10023 `int[n]'), rather than arrays of unknown size (like
10024 `int[]').) We'll get very confused by such a type since
10025 the bound of the array will not be computable in an
10026 instantiation. Besides, such types are not allowed in
10027 ISO C++, so we can do as we please here. */
10028 if (variably_modified_type_p (arg, NULL_TREE))
10032 TREE_VEC_ELT (targs, idx) = arg;
10035 case TEMPLATE_PARM_INDEX:
10036 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10038 if (TEMPLATE_PARM_LEVEL (parm)
10039 != template_decl_level (tparm))
10040 /* The PARM is not one we're trying to unify. Just check
10041 to see if it matches ARG. */
10042 return !(TREE_CODE (arg) == TREE_CODE (parm)
10043 && cp_tree_equal (parm, arg));
10045 idx = TEMPLATE_PARM_IDX (parm);
10046 targ = TREE_VEC_ELT (targs, idx);
10049 return !cp_tree_equal (targ, arg);
10051 /* [temp.deduct.type] If, in the declaration of a function template
10052 with a non-type template-parameter, the non-type
10053 template-parameter is used in an expression in the function
10054 parameter-list and, if the corresponding template-argument is
10055 deduced, the template-argument type shall match the type of the
10056 template-parameter exactly, except that a template-argument
10057 deduced from an array bound may be of any integral type.
10058 The non-type parameter might use already deduced type parameters. */
10059 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10060 if (!TREE_TYPE (arg))
10061 /* Template-parameter dependent expression. Just accept it for now.
10062 It will later be processed in convert_template_argument. */
10064 else if (same_type_p (TREE_TYPE (arg), tparm))
10066 else if ((strict & UNIFY_ALLOW_INTEGER)
10067 && (TREE_CODE (tparm) == INTEGER_TYPE
10068 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10069 /* Convert the ARG to the type of PARM; the deduced non-type
10070 template argument must exactly match the types of the
10071 corresponding parameter. */
10072 arg = fold (build_nop (TREE_TYPE (parm), arg));
10073 else if (uses_template_parms (tparm))
10074 /* We haven't deduced the type of this parameter yet. Try again
10080 TREE_VEC_ELT (targs, idx) = arg;
10085 /* A pointer-to-member constant can be unified only with
10086 another constant. */
10087 if (TREE_CODE (arg) != PTRMEM_CST)
10090 /* Just unify the class member. It would be useless (and possibly
10091 wrong, depending on the strict flags) to unify also
10092 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10093 arg refer to the same variable, even if through different
10094 classes. For instance:
10096 struct A { int x; };
10099 Unification of &A::x and &B::x must succeed. */
10100 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10101 PTRMEM_CST_MEMBER (arg), strict);
10106 if (TREE_CODE (arg) != POINTER_TYPE)
10109 /* [temp.deduct.call]
10111 A can be another pointer or pointer to member type that can
10112 be converted to the deduced A via a qualification
10113 conversion (_conv.qual_).
10115 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10116 This will allow for additional cv-qualification of the
10117 pointed-to types if appropriate. */
10119 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10120 /* The derived-to-base conversion only persists through one
10121 level of pointers. */
10122 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10124 return unify (tparms, targs, TREE_TYPE (parm),
10125 TREE_TYPE (arg), strict);
10128 case REFERENCE_TYPE:
10129 if (TREE_CODE (arg) != REFERENCE_TYPE)
10131 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10132 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10135 if (TREE_CODE (arg) != ARRAY_TYPE)
10137 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10138 != (TYPE_DOMAIN (arg) == NULL_TREE))
10140 if (TYPE_DOMAIN (parm) != NULL_TREE)
10145 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10146 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10148 /* Our representation of array types uses "N - 1" as the
10149 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10150 not an integer constant. */
10151 if (TREE_CODE (parm_max) == MINUS_EXPR)
10153 arg_max = fold_build2 (PLUS_EXPR,
10156 TREE_OPERAND (parm_max, 1));
10157 parm_max = TREE_OPERAND (parm_max, 0);
10160 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10163 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10164 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10171 case ENUMERAL_TYPE:
10173 if (TREE_CODE (arg) != TREE_CODE (parm))
10176 /* We have already checked cv-qualification at the top of the
10178 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10181 /* As far as unification is concerned, this wins. Later checks
10182 will invalidate it if necessary. */
10185 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10186 /* Type INTEGER_CST can come from ordinary constant template args. */
10188 while (TREE_CODE (arg) == NOP_EXPR)
10189 arg = TREE_OPERAND (arg, 0);
10191 if (TREE_CODE (arg) != INTEGER_CST)
10193 return !tree_int_cst_equal (parm, arg);
10198 if (TREE_CODE (arg) != TREE_VEC)
10200 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10202 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10203 if (unify (tparms, targs,
10204 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10212 if (TREE_CODE (arg) != TREE_CODE (parm))
10215 if (TYPE_PTRMEMFUNC_P (parm))
10217 if (!TYPE_PTRMEMFUNC_P (arg))
10220 return unify (tparms, targs,
10221 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10222 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10226 if (CLASSTYPE_TEMPLATE_INFO (parm))
10228 tree t = NULL_TREE;
10230 if (strict_in & UNIFY_ALLOW_DERIVED)
10232 /* First, we try to unify the PARM and ARG directly. */
10233 t = try_class_unification (tparms, targs,
10238 /* Fallback to the special case allowed in
10239 [temp.deduct.call]:
10241 If P is a class, and P has the form
10242 template-id, then A can be a derived class of
10243 the deduced A. Likewise, if P is a pointer to
10244 a class of the form template-id, A can be a
10245 pointer to a derived class pointed to by the
10247 t = get_template_base (tparms, targs, parm, arg);
10253 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10254 && (CLASSTYPE_TI_TEMPLATE (parm)
10255 == CLASSTYPE_TI_TEMPLATE (arg)))
10256 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10257 Then, we should unify `int' and `U'. */
10260 /* There's no chance of unification succeeding. */
10263 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10264 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10266 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10271 case FUNCTION_TYPE:
10272 if (TREE_CODE (arg) != TREE_CODE (parm))
10275 /* CV qualifications for methods can never be deduced, they must
10276 match exactly. We need to check them explicitly here,
10277 because type_unification_real treats them as any other
10278 cvqualified parameter. */
10279 if (TREE_CODE (parm) == METHOD_TYPE
10280 && (!check_cv_quals_for_unify
10282 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
10283 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
10286 if (unify (tparms, targs, TREE_TYPE (parm),
10287 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10289 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10290 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
10294 /* Unify a pointer to member with a pointer to member function, which
10295 deduces the type of the member as a function type. */
10296 if (TYPE_PTRMEMFUNC_P (arg))
10300 cp_cv_quals cv_quals;
10302 /* Check top-level cv qualifiers */
10303 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
10306 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10307 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
10310 /* Determine the type of the function we are unifying against. */
10311 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
10313 build_function_type (TREE_TYPE (method_type),
10314 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
10316 /* Extract the cv-qualifiers of the member function from the
10317 implicit object parameter and place them on the function
10318 type to be restored later. */
10320 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
10321 fntype = build_qualified_type (fntype, cv_quals);
10322 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
10325 if (TREE_CODE (arg) != OFFSET_TYPE)
10327 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10328 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10330 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10334 if (DECL_TEMPLATE_PARM_P (parm))
10335 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10336 if (arg != integral_constant_value (parm))
10341 case TEMPLATE_DECL:
10342 /* Matched cases are handled by the ARG == PARM test above. */
10346 gcc_assert (EXPR_P (parm));
10348 /* We must be looking at an expression. This can happen with
10352 void foo(S<I>, S<I + 2>);
10354 This is a "nondeduced context":
10358 The nondeduced contexts are:
10360 --A type that is a template-id in which one or more of
10361 the template-arguments is an expression that references
10362 a template-parameter.
10364 In these cases, we assume deduction succeeded, but don't
10365 actually infer any unifications. */
10367 if (!uses_template_parms (parm)
10368 && !template_args_equal (parm, arg))
10375 /* Note that DECL can be defined in this translation unit, if
10379 mark_definable (tree decl)
10382 DECL_NOT_REALLY_EXTERN (decl) = 1;
10383 FOR_EACH_CLONE (clone, decl)
10384 DECL_NOT_REALLY_EXTERN (clone) = 1;
10387 /* Called if RESULT is explicitly instantiated, or is a member of an
10388 explicitly instantiated class. */
10391 mark_decl_instantiated (tree result, int extern_p)
10393 SET_DECL_EXPLICIT_INSTANTIATION (result);
10395 /* If this entity has already been written out, it's too late to
10396 make any modifications. */
10397 if (TREE_ASM_WRITTEN (result))
10400 if (TREE_CODE (result) != FUNCTION_DECL)
10401 /* The TREE_PUBLIC flag for function declarations will have been
10402 set correctly by tsubst. */
10403 TREE_PUBLIC (result) = 1;
10405 /* This might have been set by an earlier implicit instantiation. */
10406 DECL_COMDAT (result) = 0;
10409 DECL_NOT_REALLY_EXTERN (result) = 0;
10412 mark_definable (result);
10413 /* Always make artificials weak. */
10414 if (DECL_ARTIFICIAL (result) && flag_weak)
10415 comdat_linkage (result);
10416 /* For WIN32 we also want to put explicit instantiations in
10417 linkonce sections. */
10418 else if (TREE_PUBLIC (result))
10419 maybe_make_one_only (result);
10422 /* If EXTERN_P, then this function will not be emitted -- unless
10423 followed by an explicit instantiation, at which point its linkage
10424 will be adjusted. If !EXTERN_P, then this function will be
10425 emitted here. In neither circumstance do we want
10426 import_export_decl to adjust the linkage. */
10427 DECL_INTERFACE_KNOWN (result) = 1;
10430 /* Given two function templates PAT1 and PAT2, return:
10432 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10433 -1 if PAT2 is more specialized than PAT1.
10434 0 if neither is more specialized.
10436 LEN indicates the number of parameters we should consider
10437 (defaulted parameters should not be considered).
10439 The 1998 std underspecified function template partial ordering, and
10440 DR214 addresses the issue. We take pairs of arguments, one from
10441 each of the templates, and deduce them against each other. One of
10442 the templates will be more specialized if all the *other*
10443 template's arguments deduce against its arguments and at least one
10444 of its arguments *does* *not* deduce against the other template's
10445 corresponding argument. Deduction is done as for class templates.
10446 The arguments used in deduction have reference and top level cv
10447 qualifiers removed. Iff both arguments were originally reference
10448 types *and* deduction succeeds in both directions, the template
10449 with the more cv-qualified argument wins for that pairing (if
10450 neither is more cv-qualified, they both are equal). Unlike regular
10451 deduction, after all the arguments have been deduced in this way,
10452 we do *not* verify the deduced template argument values can be
10453 substituted into non-deduced contexts, nor do we have to verify
10454 that all template arguments have been deduced. */
10457 more_specialized_fn (tree pat1, tree pat2, int len)
10459 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
10460 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
10461 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
10462 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
10463 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
10464 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
10465 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
10466 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
10470 /* If only one is a member function, they are unordered. */
10471 if (DECL_FUNCTION_MEMBER_P (decl1) != DECL_FUNCTION_MEMBER_P (decl2))
10474 /* Don't consider 'this' parameter. */
10475 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
10476 args1 = TREE_CHAIN (args1);
10477 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
10478 args2 = TREE_CHAIN (args2);
10480 /* If only one is a conversion operator, they are unordered. */
10481 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
10484 /* Consider the return type for a conversion function */
10485 if (DECL_CONV_FN_P (decl1))
10487 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
10488 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
10492 processing_template_decl++;
10496 tree arg1 = TREE_VALUE (args1);
10497 tree arg2 = TREE_VALUE (args2);
10498 int deduce1, deduce2;
10502 if (TREE_CODE (arg1) == REFERENCE_TYPE)
10504 arg1 = TREE_TYPE (arg1);
10505 quals1 = cp_type_quals (arg1);
10508 if (TREE_CODE (arg2) == REFERENCE_TYPE)
10510 arg2 = TREE_TYPE (arg2);
10511 quals2 = cp_type_quals (arg2);
10514 if ((quals1 < 0) != (quals2 < 0))
10516 /* Only of the args is a reference, see if we should apply
10517 array/function pointer decay to it. This is not part of
10518 DR214, but is, IMHO, consistent with the deduction rules
10519 for the function call itself, and with our earlier
10520 implementation of the underspecified partial ordering
10521 rules. (nathan). */
10524 switch (TREE_CODE (arg1))
10527 arg1 = TREE_TYPE (arg1);
10529 case FUNCTION_TYPE:
10530 arg1 = build_pointer_type (arg1);
10539 switch (TREE_CODE (arg2))
10542 arg2 = TREE_TYPE (arg2);
10544 case FUNCTION_TYPE:
10545 arg2 = build_pointer_type (arg2);
10554 arg1 = TYPE_MAIN_VARIANT (arg1);
10555 arg2 = TYPE_MAIN_VARIANT (arg2);
10557 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
10558 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
10564 if (better1 < 0 && better2 < 0)
10565 /* We've failed to deduce something in either direction.
10566 These must be unordered. */
10569 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
10571 /* Deduces in both directions, see if quals can
10572 disambiguate. Pretend the worse one failed to deduce. */
10573 if ((quals1 & quals2) == quals2)
10575 if ((quals1 & quals2) == quals1)
10578 if (deduce1 && !deduce2 && !better2)
10580 if (deduce2 && !deduce1 && !better1)
10583 args1 = TREE_CHAIN (args1);
10584 args2 = TREE_CHAIN (args2);
10587 processing_template_decl--;
10589 return (better1 > 0) - (better2 > 0);
10592 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10594 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10595 -1 if PAT2 is more specialized than PAT1.
10596 0 if neither is more specialized.
10598 FULL_ARGS is the full set of template arguments that triggers this
10599 partial ordering. */
10602 more_specialized_class (tree pat1, tree pat2, tree full_args)
10607 /* Just like what happens for functions, if we are ordering between
10608 different class template specializations, we may encounter dependent
10609 types in the arguments, and we need our dependency check functions
10610 to behave correctly. */
10611 ++processing_template_decl;
10612 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10613 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10617 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10618 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10621 --processing_template_decl;
10626 /* Return the template arguments that will produce the function signature
10627 DECL from the function template FN, with the explicit template
10628 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
10629 also match. Return NULL_TREE if no satisfactory arguments could be
10633 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
10635 int ntparms = DECL_NTPARMS (fn);
10636 tree targs = make_tree_vec (ntparms);
10638 tree decl_arg_types;
10640 /* Substitute the explicit template arguments into the type of DECL.
10641 The call to fn_type_unification will handle substitution into the
10643 decl_type = TREE_TYPE (decl);
10644 if (explicit_args && uses_template_parms (decl_type))
10647 tree converted_args;
10649 if (DECL_TEMPLATE_INFO (decl))
10650 tmpl = DECL_TI_TEMPLATE (decl);
10652 /* We can get here for some invalid specializations. */
10656 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10657 explicit_args, NULL_TREE,
10658 tf_none, /*require_all_arguments=*/0));
10659 if (converted_args == error_mark_node)
10662 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10663 if (decl_type == error_mark_node)
10667 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10668 /* Never do unification on the 'this' parameter. */
10669 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10670 decl_arg_types = TREE_CHAIN (decl_arg_types);
10672 if (fn_type_unification (fn, explicit_args, targs,
10674 (check_rettype || DECL_CONV_FN_P (fn)
10675 ? TREE_TYPE (decl_type) : NULL_TREE),
10676 DEDUCE_EXACT, LOOKUP_NORMAL))
10682 /* Return the innermost template arguments that, when applied to a
10683 template specialization whose innermost template parameters are
10684 TPARMS, and whose specialization arguments are PARMS, yield the
10687 For example, suppose we have:
10689 template <class T, class U> struct S {};
10690 template <class T> struct S<T*, int> {};
10692 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10693 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10694 int}. The resulting vector will be {double}, indicating that `T'
10695 is bound to `double'. */
10698 get_class_bindings (tree tparms, tree parms, tree args)
10700 int i, ntparms = TREE_VEC_LENGTH (tparms);
10701 tree vec = make_tree_vec (ntparms);
10703 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10707 for (i = 0; i < ntparms; ++i)
10708 if (! TREE_VEC_ELT (vec, i))
10711 if (verify_class_unification (vec, parms, args))
10717 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10718 Pick the most specialized template, and return the corresponding
10719 instantiation, or if there is no corresponding instantiation, the
10720 template itself. If there is no most specialized template,
10721 error_mark_node is returned. If there are no templates at all,
10722 NULL_TREE is returned. */
10725 most_specialized_instantiation (tree instantiations)
10729 if (!instantiations)
10732 ++processing_template_decl;
10734 champ = instantiations;
10735 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10739 if (get_bindings (TREE_VALUE (champ),
10740 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10741 NULL_TREE, /*check_ret=*/false))
10744 if (get_bindings (TREE_VALUE (fn),
10745 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10746 NULL_TREE, /*check_ret=*/false))
10752 /* Equally specialized, move to next function. If there
10753 is no next function, nothing's most specialized. */
10754 fn = TREE_CHAIN (fn);
10760 /* Now verify that champ is better than everything earlier in the
10761 instantiation list. */
10762 for (fn = instantiations; fn != champ; fn = TREE_CHAIN (fn))
10763 if (get_bindings (TREE_VALUE (champ),
10764 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10765 NULL_TREE, /*check_ret=*/false)
10766 || !get_bindings (TREE_VALUE (fn),
10767 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10768 NULL_TREE, /*check_ret=*/false))
10774 processing_template_decl--;
10777 return error_mark_node;
10779 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10782 /* Return the most specialized of the list of templates in FNS that can
10783 produce an instantiation matching DECL, given the explicit template
10784 arguments EXPLICIT_ARGS. */
10787 most_specialized (tree fns, tree decl, tree explicit_args)
10789 tree candidates = NULL_TREE;
10792 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10794 tree candidate = TREE_VALUE (fn);
10796 args = get_bindings (candidate, decl, explicit_args, /*check_ret=*/true);
10798 candidates = tree_cons (NULL_TREE, candidate, candidates);
10801 return most_specialized_instantiation (candidates);
10804 /* If DECL is a specialization of some template, return the most
10805 general such template. Otherwise, returns NULL_TREE.
10807 For example, given:
10809 template <class T> struct S { template <class U> void f(U); };
10811 if TMPL is `template <class U> void S<int>::f(U)' this will return
10812 the full template. This function will not trace past partial
10813 specializations, however. For example, given in addition:
10815 template <class T> struct S<T*> { template <class U> void f(U); };
10817 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10818 `template <class T> template <class U> S<T*>::f(U)'. */
10821 most_general_template (tree decl)
10823 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10824 an immediate specialization. */
10825 if (TREE_CODE (decl) == FUNCTION_DECL)
10827 if (DECL_TEMPLATE_INFO (decl)) {
10828 decl = DECL_TI_TEMPLATE (decl);
10830 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10831 template friend. */
10832 if (TREE_CODE (decl) != TEMPLATE_DECL)
10838 /* Look for more and more general templates. */
10839 while (DECL_TEMPLATE_INFO (decl))
10841 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10842 (See cp-tree.h for details.) */
10843 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10846 if (CLASS_TYPE_P (TREE_TYPE (decl))
10847 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10850 /* Stop if we run into an explicitly specialized class template. */
10851 if (!DECL_NAMESPACE_SCOPE_P (decl)
10852 && DECL_CONTEXT (decl)
10853 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10856 decl = DECL_TI_TEMPLATE (decl);
10862 /* Return the most specialized of the class template specializations
10863 of TMPL which can produce an instantiation matching ARGS, or
10864 error_mark_node if the choice is ambiguous. */
10867 most_specialized_class (tree tmpl, tree args)
10869 tree list = NULL_TREE;
10874 tmpl = most_general_template (tmpl);
10875 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10878 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10881 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10882 TREE_TYPE (list) = TREE_TYPE (t);
10891 t = TREE_CHAIN (t);
10892 for (; t; t = TREE_CHAIN (t))
10894 fate = more_specialized_class (champ, t, args);
10901 t = TREE_CHAIN (t);
10903 return error_mark_node;
10909 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10911 fate = more_specialized_class (champ, t, args);
10913 return error_mark_node;
10919 /* Explicitly instantiate DECL. */
10922 do_decl_instantiation (tree decl, tree storage)
10924 tree result = NULL_TREE;
10928 /* An error occurred, for which grokdeclarator has already issued
10929 an appropriate message. */
10931 else if (! DECL_LANG_SPECIFIC (decl))
10933 error ("explicit instantiation of non-template %q#D", decl);
10936 else if (TREE_CODE (decl) == VAR_DECL)
10938 /* There is an asymmetry here in the way VAR_DECLs and
10939 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10940 the latter, the DECL we get back will be marked as a
10941 template instantiation, and the appropriate
10942 DECL_TEMPLATE_INFO will be set up. This does not happen for
10943 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10944 should handle VAR_DECLs as it currently handles
10946 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10947 if (!result || TREE_CODE (result) != VAR_DECL)
10949 error ("no matching template for %qD found", decl);
10953 else if (TREE_CODE (decl) != FUNCTION_DECL)
10955 error ("explicit instantiation of %q#D", decl);
10961 /* Check for various error cases. Note that if the explicit
10962 instantiation is valid the RESULT will currently be marked as an
10963 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10964 until we get here. */
10966 if (DECL_TEMPLATE_SPECIALIZATION (result))
10968 /* DR 259 [temp.spec].
10970 Both an explicit instantiation and a declaration of an explicit
10971 specialization shall not appear in a program unless the explicit
10972 instantiation follows a declaration of the explicit specialization.
10974 For a given set of template parameters, if an explicit
10975 instantiation of a template appears after a declaration of an
10976 explicit specialization for that template, the explicit
10977 instantiation has no effect. */
10980 else if (DECL_EXPLICIT_INSTANTIATION (result))
10984 No program shall explicitly instantiate any template more
10987 We check DECL_NOT_REALLY_EXTERN so as not to complain when
10988 the first instantiation was `extern' and the second is not,
10989 and EXTERN_P for the opposite case. */
10990 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
10991 pedwarn ("duplicate explicit instantiation of %q#D", result);
10992 /* If an "extern" explicit instantiation follows an ordinary
10993 explicit instantiation, the template is instantiated. */
10997 else if (!DECL_IMPLICIT_INSTANTIATION (result))
10999 error ("no matching template for %qD found", result);
11002 else if (!DECL_TEMPLATE_INFO (result))
11004 pedwarn ("explicit instantiation of non-template %q#D", result);
11008 if (storage == NULL_TREE)
11010 else if (storage == ridpointers[(int) RID_EXTERN])
11012 if (pedantic && !in_system_header)
11013 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
11018 error ("storage class %qD applied to template instantiation", storage);
11020 mark_decl_instantiated (result, extern_p);
11022 instantiate_decl (result, /*defer_ok=*/1,
11023 /*expl_inst_class_mem_p=*/false);
11027 mark_class_instantiated (tree t, int extern_p)
11029 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
11030 SET_CLASSTYPE_INTERFACE_KNOWN (t);
11031 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
11032 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
11035 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
11036 rest_of_type_compilation (t, 1);
11040 /* Called from do_type_instantiation through binding_table_foreach to
11041 do recursive instantiation for the type bound in ENTRY. */
11043 bt_instantiate_type_proc (binding_entry entry, void *data)
11045 tree storage = *(tree *) data;
11047 if (IS_AGGR_TYPE (entry->type)
11048 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
11049 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
11052 /* Called from do_type_instantiation to instantiate a member
11053 (a member function or a static member variable) of an
11054 explicitly instantiated class template. */
11056 instantiate_class_member (tree decl, int extern_p)
11058 mark_decl_instantiated (decl, extern_p);
11060 instantiate_decl (decl, /*defer_ok=*/1,
11061 /*expl_inst_class_mem_p=*/true);
11064 /* Perform an explicit instantiation of template class T. STORAGE, if
11065 non-null, is the RID for extern, inline or static. COMPLAIN is
11066 nonzero if this is called from the parser, zero if called recursively,
11067 since the standard is unclear (as detailed below). */
11070 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
11075 int previous_instantiation_extern_p = 0;
11077 if (TREE_CODE (t) == TYPE_DECL)
11080 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
11082 error ("explicit instantiation of non-template type %qT", t);
11088 if (!COMPLETE_TYPE_P (t))
11090 if (complain & tf_error)
11091 error ("explicit instantiation of %q#T before definition of template",
11096 if (storage != NULL_TREE)
11098 if (pedantic && !in_system_header)
11099 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
11102 if (storage == ridpointers[(int) RID_INLINE])
11104 else if (storage == ridpointers[(int) RID_EXTERN])
11106 else if (storage == ridpointers[(int) RID_STATIC])
11110 error ("storage class %qD applied to template instantiation",
11116 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
11118 /* DR 259 [temp.spec].
11120 Both an explicit instantiation and a declaration of an explicit
11121 specialization shall not appear in a program unless the explicit
11122 instantiation follows a declaration of the explicit specialization.
11124 For a given set of template parameters, if an explicit
11125 instantiation of a template appears after a declaration of an
11126 explicit specialization for that template, the explicit
11127 instantiation has no effect. */
11130 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
11134 No program shall explicitly instantiate any template more
11137 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
11138 instantiation was `extern'. If EXTERN_P then the second is.
11139 These cases are OK. */
11140 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11142 if (!previous_instantiation_extern_p && !extern_p
11143 && (complain & tf_error))
11144 pedwarn ("duplicate explicit instantiation of %q#T", t);
11146 /* If we've already instantiated the template, just return now. */
11147 if (!CLASSTYPE_INTERFACE_ONLY (t))
11151 mark_class_instantiated (t, extern_p);
11159 /* In contrast to implicit instantiation, where only the
11160 declarations, and not the definitions, of members are
11161 instantiated, we have here:
11165 The explicit instantiation of a class template specialization
11166 implies the instantiation of all of its members not
11167 previously explicitly specialized in the translation unit
11168 containing the explicit instantiation.
11170 Of course, we can't instantiate member template classes, since
11171 we don't have any arguments for them. Note that the standard
11172 is unclear on whether the instantiation of the members are
11173 *explicit* instantiations or not. However, the most natural
11174 interpretation is that it should be an explicit instantiation. */
11177 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11178 if (TREE_CODE (tmp) == FUNCTION_DECL
11179 && DECL_TEMPLATE_INSTANTIATION (tmp))
11180 instantiate_class_member (tmp, extern_p);
11182 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11183 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11184 instantiate_class_member (tmp, extern_p);
11186 if (CLASSTYPE_NESTED_UTDS (t))
11187 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11188 bt_instantiate_type_proc, &storage);
11192 /* Given a function DECL, which is a specialization of TMPL, modify
11193 DECL to be a re-instantiation of TMPL with the same template
11194 arguments. TMPL should be the template into which tsubst'ing
11195 should occur for DECL, not the most general template.
11197 One reason for doing this is a scenario like this:
11200 void f(const T&, int i);
11202 void g() { f(3, 7); }
11205 void f(const T& t, const int i) { }
11207 Note that when the template is first instantiated, with
11208 instantiate_template, the resulting DECL will have no name for the
11209 first parameter, and the wrong type for the second. So, when we go
11210 to instantiate the DECL, we regenerate it. */
11213 regenerate_decl_from_template (tree decl, tree tmpl)
11215 /* The arguments used to instantiate DECL, from the most general
11220 args = DECL_TI_ARGS (decl);
11221 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11223 /* Make sure that we can see identifiers, and compute access
11225 push_access_scope (decl);
11227 if (TREE_CODE (decl) == FUNCTION_DECL)
11235 args_depth = TMPL_ARGS_DEPTH (args);
11236 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11237 if (args_depth > parms_depth)
11238 args = get_innermost_template_args (args, parms_depth);
11240 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11241 args, tf_error, NULL_TREE);
11243 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11246 /* Merge parameter declarations. */
11247 decl_parm = skip_artificial_parms_for (decl,
11248 DECL_ARGUMENTS (decl));
11250 = skip_artificial_parms_for (code_pattern,
11251 DECL_ARGUMENTS (code_pattern));
11257 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11258 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11259 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11261 parm_type = type_decays_to (parm_type);
11262 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11263 TREE_TYPE (decl_parm) = parm_type;
11264 attributes = DECL_ATTRIBUTES (pattern_parm);
11265 if (DECL_ATTRIBUTES (decl_parm) != attributes)
11267 DECL_ATTRIBUTES (decl_parm) = attributes;
11268 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
11270 decl_parm = TREE_CHAIN (decl_parm);
11271 pattern_parm = TREE_CHAIN (pattern_parm);
11274 /* Merge additional specifiers from the CODE_PATTERN. */
11275 if (DECL_DECLARED_INLINE_P (code_pattern)
11276 && !DECL_DECLARED_INLINE_P (decl))
11277 DECL_DECLARED_INLINE_P (decl) = 1;
11278 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11279 DECL_INLINE (decl) = 1;
11281 else if (TREE_CODE (decl) == VAR_DECL)
11282 DECL_INITIAL (decl) =
11283 tsubst_expr (DECL_INITIAL (code_pattern), args,
11284 tf_error, DECL_TI_TEMPLATE (decl));
11286 gcc_unreachable ();
11288 pop_access_scope (decl);
11291 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11292 substituted to get DECL. */
11295 template_for_substitution (tree decl)
11297 tree tmpl = DECL_TI_TEMPLATE (decl);
11299 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11300 for the instantiation. This is not always the most general
11301 template. Consider, for example:
11304 struct S { template <class U> void f();
11305 template <> void f<int>(); };
11307 and an instantiation of S<double>::f<int>. We want TD to be the
11308 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11309 while (/* An instantiation cannot have a definition, so we need a
11310 more general template. */
11311 DECL_TEMPLATE_INSTANTIATION (tmpl)
11312 /* We must also deal with friend templates. Given:
11314 template <class T> struct S {
11315 template <class U> friend void f() {};
11318 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11319 so far as the language is concerned, but that's still
11320 where we get the pattern for the instantiation from. On
11321 other hand, if the definition comes outside the class, say:
11323 template <class T> struct S {
11324 template <class U> friend void f();
11326 template <class U> friend void f() {}
11328 we don't need to look any further. That's what the check for
11329 DECL_INITIAL is for. */
11330 || (TREE_CODE (decl) == FUNCTION_DECL
11331 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11332 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11334 /* The present template, TD, should not be a definition. If it
11335 were a definition, we should be using it! Note that we
11336 cannot restructure the loop to just keep going until we find
11337 a template with a definition, since that might go too far if
11338 a specialization was declared, but not defined. */
11339 gcc_assert (TREE_CODE (decl) != VAR_DECL
11340 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11342 /* Fetch the more general template. */
11343 tmpl = DECL_TI_TEMPLATE (tmpl);
11349 /* Produce the definition of D, a _DECL generated from a template. If
11350 DEFER_OK is nonzero, then we don't have to actually do the
11351 instantiation now; we just have to do it sometime. Normally it is
11352 an error if this is an explicit instantiation but D is undefined.
11353 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
11354 explicitly instantiated class template. */
11357 instantiate_decl (tree d, int defer_ok,
11358 bool expl_inst_class_mem_p)
11360 tree tmpl = DECL_TI_TEMPLATE (d);
11367 bool pattern_defined;
11369 location_t saved_loc = input_location;
11372 /* This function should only be used to instantiate templates for
11373 functions and static member variables. */
11374 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11375 || TREE_CODE (d) == VAR_DECL);
11377 /* Variables are never deferred; if instantiation is required, they
11378 are instantiated right away. That allows for better code in the
11379 case that an expression refers to the value of the variable --
11380 if the variable has a constant value the referring expression can
11381 take advantage of that fact. */
11382 if (TREE_CODE (d) == VAR_DECL)
11385 /* Don't instantiate cloned functions. Instead, instantiate the
11386 functions they cloned. */
11387 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11388 d = DECL_CLONED_FUNCTION (d);
11390 if (DECL_TEMPLATE_INSTANTIATED (d))
11391 /* D has already been instantiated. It might seem reasonable to
11392 check whether or not D is an explicit instantiation, and, if so,
11393 stop here. But when an explicit instantiation is deferred
11394 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11395 is set, even though we still need to do the instantiation. */
11398 /* If we already have a specialization of this declaration, then
11399 there's no reason to instantiate it. Note that
11400 retrieve_specialization gives us both instantiations and
11401 specializations, so we must explicitly check
11402 DECL_TEMPLATE_SPECIALIZATION. */
11403 gen_tmpl = most_general_template (tmpl);
11404 gen_args = DECL_TI_ARGS (d);
11405 spec = retrieve_specialization (gen_tmpl, gen_args,
11406 /*class_specializations_p=*/false);
11407 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11410 /* This needs to happen before any tsubsting. */
11411 if (! push_tinst_level (d))
11414 timevar_push (TV_PARSE);
11416 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11417 for the instantiation. */
11418 td = template_for_substitution (d);
11419 code_pattern = DECL_TEMPLATE_RESULT (td);
11421 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11422 || DECL_TEMPLATE_SPECIALIZATION (td))
11423 /* In the case of a friend template whose definition is provided
11424 outside the class, we may have too many arguments. Drop the
11425 ones we don't need. The same is true for specializations. */
11426 args = get_innermost_template_args
11427 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11431 if (TREE_CODE (d) == FUNCTION_DECL)
11432 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11434 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11436 /* We may be in the middle of deferred access check. Disable it now. */
11437 push_deferring_access_checks (dk_no_deferred);
11439 /* Unless an explicit instantiation directive has already determined
11440 the linkage of D, remember that a definition is available for
11442 if (pattern_defined
11443 && !DECL_INTERFACE_KNOWN (d)
11444 && !DECL_NOT_REALLY_EXTERN (d))
11445 mark_definable (d);
11447 input_location = DECL_SOURCE_LOCATION (d);
11449 /* If D is a member of an explicitly instantiated class template,
11450 and no definition is available, treat it like an implicit
11452 if (!pattern_defined && expl_inst_class_mem_p
11453 && DECL_EXPLICIT_INSTANTIATION (d))
11455 DECL_NOT_REALLY_EXTERN (d) = 0;
11456 DECL_INTERFACE_KNOWN (d) = 0;
11457 SET_DECL_IMPLICIT_INSTANTIATION (d);
11462 /* Recheck the substitutions to obtain any warning messages
11463 about ignoring cv qualifiers. */
11464 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11465 tree type = TREE_TYPE (gen);
11467 /* Make sure that we can see identifiers, and compute access
11468 correctly. D is already the target FUNCTION_DECL with the
11470 push_access_scope (d);
11472 if (TREE_CODE (gen) == FUNCTION_DECL)
11474 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11475 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11476 tf_error | tf_warning, d);
11477 /* Don't simply tsubst the function type, as that will give
11478 duplicate warnings about poor parameter qualifications.
11479 The function arguments are the same as the decl_arguments
11480 without the top level cv qualifiers. */
11481 type = TREE_TYPE (type);
11483 tsubst (type, gen_args, tf_error | tf_warning, d);
11485 pop_access_scope (d);
11488 /* Check to see whether we know that this template will be
11489 instantiated in some other file, as with "extern template"
11491 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
11492 /* In general, we do not instantiate such templates... */
11494 /* ... but we instantiate inline functions so that we can inline
11496 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
11497 /* ... we instantiate static data members whose values are
11498 needed in integral constant expressions. */
11499 && ! (TREE_CODE (d) == VAR_DECL
11500 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
11502 /* Defer all other templates, unless we have been explicitly
11503 forbidden from doing so. */
11504 if (/* If there is no definition, we cannot instantiate the
11507 /* If it's OK to postpone instantiation, do so. */
11509 /* If this is a static data member that will be defined
11510 elsewhere, we don't want to instantiate the entire data
11511 member, but we do want to instantiate the initializer so that
11512 we can substitute that elsewhere. */
11513 || (external_p && TREE_CODE (d) == VAR_DECL))
11515 /* The definition of the static data member is now required so
11516 we must substitute the initializer. */
11517 if (TREE_CODE (d) == VAR_DECL
11518 && !DECL_INITIAL (d)
11519 && DECL_INITIAL (code_pattern))
11521 push_nested_class (DECL_CONTEXT (d));
11523 = tsubst_expr (DECL_INITIAL (code_pattern),
11525 tf_error | tf_warning, NULL_TREE);
11526 pop_nested_class ();
11529 /* We restore the source position here because it's used by
11530 add_pending_template. */
11531 input_location = saved_loc;
11533 if (at_eof && !pattern_defined
11534 && DECL_EXPLICIT_INSTANTIATION (d))
11537 The definition of a non-exported function template, a
11538 non-exported member function template, or a non-exported
11539 member function or static data member of a class template
11540 shall be present in every translation unit in which it is
11541 explicitly instantiated. */
11543 ("explicit instantiation of %qD but no definition available", d);
11545 /* ??? Historically, we have instantiated inline functions, even
11546 when marked as "extern template". */
11547 if (!(external_p && TREE_CODE (d) == VAR_DECL))
11548 add_pending_template (d);
11551 /* Tell the repository that D is available in this translation unit
11552 -- and see if it is supposed to be instantiated here. */
11553 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11555 /* In a PCH file, despite the fact that the repository hasn't
11556 requested instantiation in the PCH it is still possible that
11557 an instantiation will be required in a file that includes the
11560 add_pending_template (d);
11561 /* Instantiate inline functions so that the inliner can do its
11562 job, even though we'll not be emitting a copy of this
11564 if (!(TREE_CODE (d) == FUNCTION_DECL
11565 && flag_inline_trees
11566 && DECL_DECLARED_INLINE_P (d)))
11570 need_push = !cfun || !global_bindings_p ();
11572 push_to_top_level ();
11574 /* Mark D as instantiated so that recursive calls to
11575 instantiate_decl do not try to instantiate it again. */
11576 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11578 /* Regenerate the declaration in case the template has been modified
11579 by a subsequent redeclaration. */
11580 regenerate_decl_from_template (d, td);
11582 /* We already set the file and line above. Reset them now in case
11583 they changed as a result of calling regenerate_decl_from_template. */
11584 input_location = DECL_SOURCE_LOCATION (d);
11586 if (TREE_CODE (d) == VAR_DECL)
11588 /* Clear out DECL_RTL; whatever was there before may not be right
11589 since we've reset the type of the declaration. */
11590 SET_DECL_RTL (d, NULL_RTX);
11591 DECL_IN_AGGR_P (d) = 0;
11593 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11594 initializer. That function will defer actual emission until
11595 we have a chance to determine linkage. */
11596 DECL_EXTERNAL (d) = 0;
11598 /* Enter the scope of D so that access-checking works correctly. */
11599 push_nested_class (DECL_CONTEXT (d));
11600 cp_finish_decl (d, DECL_INITIAL (d), NULL_TREE, 0);
11601 pop_nested_class ();
11603 else if (TREE_CODE (d) == FUNCTION_DECL)
11605 htab_t saved_local_specializations;
11610 /* Save away the current list, in case we are instantiating one
11611 template from within the body of another. */
11612 saved_local_specializations = local_specializations;
11614 /* Set up the list of local specializations. */
11615 local_specializations = htab_create (37,
11616 hash_local_specialization,
11617 eq_local_specializations,
11620 /* Set up context. */
11621 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11623 /* Create substitution entries for the parameters. */
11624 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11625 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11626 spec_parm = DECL_ARGUMENTS (d);
11627 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11629 register_local_specialization (spec_parm, tmpl_parm);
11630 spec_parm = skip_artificial_parms_for (d, spec_parm);
11631 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11635 register_local_specialization (spec_parm, tmpl_parm);
11636 tmpl_parm = TREE_CHAIN (tmpl_parm);
11637 spec_parm = TREE_CHAIN (spec_parm);
11639 gcc_assert (!spec_parm);
11641 /* Substitute into the body of the function. */
11642 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11643 tf_error | tf_warning, tmpl);
11645 /* We don't need the local specializations any more. */
11646 htab_delete (local_specializations);
11647 local_specializations = saved_local_specializations;
11649 /* Finish the function. */
11650 d = finish_function (0);
11651 expand_or_defer_fn (d);
11654 /* We're not deferring instantiation any more. */
11655 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11658 pop_from_top_level ();
11661 input_location = saved_loc;
11662 pop_deferring_access_checks ();
11663 pop_tinst_level ();
11665 timevar_pop (TV_PARSE);
11670 /* Run through the list of templates that we wish we could
11671 instantiate, and instantiate any we can. RETRIES is the
11672 number of times we retry pending template instantiation. */
11675 instantiate_pending_templates (int retries)
11678 tree last = NULL_TREE;
11680 location_t saved_loc = input_location;
11681 int saved_in_system_header = in_system_header;
11683 /* Instantiating templates may trigger vtable generation. This in turn
11684 may require further template instantiations. We place a limit here
11685 to avoid infinite loop. */
11686 if (pending_templates && retries >= max_tinst_depth)
11688 error ("template instantiation depth exceeds maximum of %d"
11689 " instantiating %q+D, possibly from virtual table generation"
11690 " (use -ftemplate-depth-NN to increase the maximum)",
11691 max_tinst_depth, TREE_VALUE (pending_templates));
11699 t = &pending_templates;
11702 tree instantiation = TREE_VALUE (*t);
11704 reopen_tinst_level (TREE_PURPOSE (*t));
11706 if (TYPE_P (instantiation))
11710 if (!COMPLETE_TYPE_P (instantiation))
11712 instantiate_class_template (instantiation);
11713 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11714 for (fn = TYPE_METHODS (instantiation);
11716 fn = TREE_CHAIN (fn))
11717 if (! DECL_ARTIFICIAL (fn))
11718 instantiate_decl (fn,
11720 /*expl_inst_class_mem_p=*/false);
11721 if (COMPLETE_TYPE_P (instantiation))
11725 if (COMPLETE_TYPE_P (instantiation))
11726 /* If INSTANTIATION has been instantiated, then we don't
11727 need to consider it again in the future. */
11728 *t = TREE_CHAIN (*t);
11732 t = &TREE_CHAIN (*t);
11737 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11738 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11741 = instantiate_decl (instantiation,
11743 /*expl_inst_class_mem_p=*/false);
11744 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11748 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11749 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11750 /* If INSTANTIATION has been instantiated, then we don't
11751 need to consider it again in the future. */
11752 *t = TREE_CHAIN (*t);
11756 t = &TREE_CHAIN (*t);
11760 current_tinst_level = NULL_TREE;
11762 last_pending_template = last;
11764 while (reconsider);
11766 input_location = saved_loc;
11767 in_system_header = saved_in_system_header;
11770 /* Substitute ARGVEC into T, which is a list of initializers for
11771 either base class or a non-static data member. The TREE_PURPOSEs
11772 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11773 instantiate_decl. */
11776 tsubst_initializer_list (tree t, tree argvec)
11778 tree inits = NULL_TREE;
11780 for (; t; t = TREE_CHAIN (t))
11785 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11787 decl = expand_member_init (decl);
11788 if (decl && !DECL_P (decl))
11789 in_base_initializer = 1;
11791 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11793 in_base_initializer = 0;
11797 init = build_tree_list (decl, init);
11798 TREE_CHAIN (init) = inits;
11805 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11808 set_current_access_from_decl (tree decl)
11810 if (TREE_PRIVATE (decl))
11811 current_access_specifier = access_private_node;
11812 else if (TREE_PROTECTED (decl))
11813 current_access_specifier = access_protected_node;
11815 current_access_specifier = access_public_node;
11818 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11819 is the instantiation (which should have been created with
11820 start_enum) and ARGS are the template arguments to use. */
11823 tsubst_enum (tree tag, tree newtag, tree args)
11827 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11832 decl = TREE_VALUE (e);
11833 /* Note that in a template enum, the TREE_VALUE is the
11834 CONST_DECL, not the corresponding INTEGER_CST. */
11835 value = tsubst_expr (DECL_INITIAL (decl),
11836 args, tf_error | tf_warning,
11839 /* Give this enumeration constant the correct access. */
11840 set_current_access_from_decl (decl);
11842 /* Actually build the enumerator itself. */
11843 build_enumerator (DECL_NAME (decl), value, newtag);
11846 finish_enum (newtag);
11847 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11848 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11851 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11852 its type -- but without substituting the innermost set of template
11853 arguments. So, innermost set of template parameters will appear in
11857 get_mostly_instantiated_function_type (tree decl)
11865 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11866 targs = DECL_TI_ARGS (decl);
11867 tparms = DECL_TEMPLATE_PARMS (tmpl);
11868 parm_depth = TMPL_PARMS_DEPTH (tparms);
11870 /* There should be as many levels of arguments as there are levels
11872 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11874 fn_type = TREE_TYPE (tmpl);
11876 if (parm_depth == 1)
11877 /* No substitution is necessary. */
11881 int i, save_access_control;
11884 /* Replace the innermost level of the TARGS with NULL_TREEs to
11885 let tsubst know not to substitute for those parameters. */
11886 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11887 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11888 SET_TMPL_ARGS_LEVEL (partial_args, i,
11889 TMPL_ARGS_LEVEL (targs, i));
11890 SET_TMPL_ARGS_LEVEL (partial_args,
11891 TMPL_ARGS_DEPTH (targs),
11892 make_tree_vec (DECL_NTPARMS (tmpl)));
11894 /* Disable access control as this function is used only during
11896 save_access_control = flag_access_control;
11897 flag_access_control = 0;
11899 ++processing_template_decl;
11900 /* Now, do the (partial) substitution to figure out the
11901 appropriate function type. */
11902 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11903 --processing_template_decl;
11905 /* Substitute into the template parameters to obtain the real
11906 innermost set of parameters. This step is important if the
11907 innermost set of template parameters contains value
11908 parameters whose types depend on outer template parameters. */
11909 TREE_VEC_LENGTH (partial_args)--;
11910 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11912 flag_access_control = save_access_control;
11918 /* Return truthvalue if we're processing a template different from
11919 the last one involved in diagnostics. */
11921 problematic_instantiation_changed (void)
11923 return last_template_error_tick != tinst_level_tick;
11926 /* Remember current template involved in diagnostics. */
11928 record_last_problematic_instantiation (void)
11930 last_template_error_tick = tinst_level_tick;
11934 current_instantiation (void)
11936 return current_tinst_level;
11939 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11940 type. Return zero for ok, nonzero for disallowed. Issue error and
11941 warning messages under control of COMPLAIN. */
11944 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11946 if (INTEGRAL_TYPE_P (type))
11948 else if (POINTER_TYPE_P (type))
11950 else if (TYPE_PTR_TO_MEMBER_P (type))
11952 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11954 else if (TREE_CODE (type) == TYPENAME_TYPE)
11957 if (complain & tf_error)
11958 error ("%q#T is not a valid type for a template constant parameter", type);
11962 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11963 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11966 dependent_type_p_r (tree type)
11972 A type is dependent if it is:
11974 -- a template parameter. Template template parameters are types
11975 for us (since TYPE_P holds true for them) so we handle
11977 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11978 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11980 /* -- a qualified-id with a nested-name-specifier which contains a
11981 class-name that names a dependent type or whose unqualified-id
11982 names a dependent type. */
11983 if (TREE_CODE (type) == TYPENAME_TYPE)
11985 /* -- a cv-qualified type where the cv-unqualified type is
11987 type = TYPE_MAIN_VARIANT (type);
11988 /* -- a compound type constructed from any dependent type. */
11989 if (TYPE_PTR_TO_MEMBER_P (type))
11990 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11991 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11993 else if (TREE_CODE (type) == POINTER_TYPE
11994 || TREE_CODE (type) == REFERENCE_TYPE)
11995 return dependent_type_p (TREE_TYPE (type));
11996 else if (TREE_CODE (type) == FUNCTION_TYPE
11997 || TREE_CODE (type) == METHOD_TYPE)
12001 if (dependent_type_p (TREE_TYPE (type)))
12003 for (arg_type = TYPE_ARG_TYPES (type);
12005 arg_type = TREE_CHAIN (arg_type))
12006 if (dependent_type_p (TREE_VALUE (arg_type)))
12010 /* -- an array type constructed from any dependent type or whose
12011 size is specified by a constant expression that is
12012 value-dependent. */
12013 if (TREE_CODE (type) == ARRAY_TYPE)
12015 if (TYPE_DOMAIN (type)
12016 && ((value_dependent_expression_p
12017 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
12018 || (type_dependent_expression_p
12019 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
12021 return dependent_type_p (TREE_TYPE (type));
12024 /* -- a template-id in which either the template name is a template
12026 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
12028 /* ... or any of the template arguments is a dependent type or
12029 an expression that is type-dependent or value-dependent. */
12030 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
12031 && (any_dependent_template_arguments_p
12032 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
12035 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
12036 expression is not type-dependent, then it should already been
12038 if (TREE_CODE (type) == TYPEOF_TYPE)
12041 /* The standard does not specifically mention types that are local
12042 to template functions or local classes, but they should be
12043 considered dependent too. For example:
12045 template <int I> void f() {
12050 The size of `E' cannot be known until the value of `I' has been
12051 determined. Therefore, `E' must be considered dependent. */
12052 scope = TYPE_CONTEXT (type);
12053 if (scope && TYPE_P (scope))
12054 return dependent_type_p (scope);
12055 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
12056 return type_dependent_expression_p (scope);
12058 /* Other types are non-dependent. */
12062 /* Returns TRUE if TYPE is dependent, in the sense of
12063 [temp.dep.type]. */
12066 dependent_type_p (tree type)
12068 /* If there are no template parameters in scope, then there can't be
12069 any dependent types. */
12070 if (!processing_template_decl)
12073 /* If the type is NULL, we have not computed a type for the entity
12074 in question; in that case, the type is dependent. */
12078 /* Erroneous types can be considered non-dependent. */
12079 if (type == error_mark_node)
12082 /* If we have not already computed the appropriate value for TYPE,
12084 if (!TYPE_DEPENDENT_P_VALID (type))
12086 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
12087 TYPE_DEPENDENT_P_VALID (type) = 1;
12090 return TYPE_DEPENDENT_P (type);
12093 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
12096 dependent_scope_ref_p (tree expression, bool criterion (tree))
12101 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
12103 if (!TYPE_P (TREE_OPERAND (expression, 0)))
12106 scope = TREE_OPERAND (expression, 0);
12107 name = TREE_OPERAND (expression, 1);
12111 An id-expression is type-dependent if it contains a
12112 nested-name-specifier that contains a class-name that names a
12114 /* The suggested resolution to Core Issue 2 implies that if the
12115 qualifying type is the current class, then we must peek
12118 && currently_open_class (scope)
12119 && !criterion (name))
12121 if (dependent_type_p (scope))
12127 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
12128 [temp.dep.constexpr] */
12131 value_dependent_expression_p (tree expression)
12133 if (!processing_template_decl)
12136 /* A name declared with a dependent type. */
12137 if (DECL_P (expression) && type_dependent_expression_p (expression))
12140 switch (TREE_CODE (expression))
12142 case IDENTIFIER_NODE:
12143 /* A name that has not been looked up -- must be dependent. */
12146 case TEMPLATE_PARM_INDEX:
12147 /* A non-type template parm. */
12151 /* A non-type template parm. */
12152 if (DECL_TEMPLATE_PARM_P (expression))
12157 /* A constant with integral or enumeration type and is initialized
12158 with an expression that is value-dependent. */
12159 if (DECL_INITIAL (expression)
12160 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
12161 && value_dependent_expression_p (DECL_INITIAL (expression)))
12165 case DYNAMIC_CAST_EXPR:
12166 case STATIC_CAST_EXPR:
12167 case CONST_CAST_EXPR:
12168 case REINTERPRET_CAST_EXPR:
12170 /* These expressions are value-dependent if the type to which
12171 the cast occurs is dependent or the expression being casted
12172 is value-dependent. */
12174 tree type = TREE_TYPE (expression);
12176 if (dependent_type_p (type))
12179 /* A functional cast has a list of operands. */
12180 expression = TREE_OPERAND (expression, 0);
12183 /* If there are no operands, it must be an expression such
12184 as "int()". This should not happen for aggregate types
12185 because it would form non-constant expressions. */
12186 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12191 if (TREE_CODE (expression) == TREE_LIST)
12193 for (; expression; expression = TREE_CHAIN (expression))
12194 if (value_dependent_expression_p (TREE_VALUE (expression)))
12199 return value_dependent_expression_p (expression);
12204 /* A `sizeof' expression is value-dependent if the operand is
12206 expression = TREE_OPERAND (expression, 0);
12207 if (TYPE_P (expression))
12208 return dependent_type_p (expression);
12209 return type_dependent_expression_p (expression);
12212 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12214 case COMPONENT_REF:
12215 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12216 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12219 /* A CALL_EXPR is value-dependent if any argument is
12220 value-dependent. Why do we have to handle CALL_EXPRs in this
12221 function at all? First, some function calls, those for which
12222 value_dependent_expression_p is true, man appear in constant
12223 expressions. Second, there appear to be bugs which result in
12224 other CALL_EXPRs reaching this point. */
12226 tree function = TREE_OPERAND (expression, 0);
12227 tree args = TREE_OPERAND (expression, 1);
12229 if (value_dependent_expression_p (function))
12235 if (TREE_CODE (args) == TREE_LIST)
12237 for (; args; args = TREE_CHAIN (args))
12238 if (value_dependent_expression_p (TREE_VALUE (args)))
12243 return value_dependent_expression_p (args);
12247 /* A constant expression is value-dependent if any subexpression is
12248 value-dependent. */
12249 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12251 case tcc_reference:
12253 return (value_dependent_expression_p
12254 (TREE_OPERAND (expression, 0)));
12256 case tcc_comparison:
12258 return ((value_dependent_expression_p
12259 (TREE_OPERAND (expression, 0)))
12260 || (value_dependent_expression_p
12261 (TREE_OPERAND (expression, 1))));
12263 case tcc_expression:
12266 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12267 /* In some cases, some of the operands may be missing.
12268 (For example, in the case of PREDECREMENT_EXPR, the
12269 amount to increment by may be missing.) That doesn't
12270 make the expression dependent. */
12271 if (TREE_OPERAND (expression, i)
12272 && (value_dependent_expression_p
12273 (TREE_OPERAND (expression, i))))
12283 /* The expression is not value-dependent. */
12287 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12288 [temp.dep.expr]. */
12291 type_dependent_expression_p (tree expression)
12293 if (!processing_template_decl)
12296 if (expression == error_mark_node)
12299 /* An unresolved name is always dependent. */
12300 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12303 /* Some expression forms are never type-dependent. */
12304 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12305 || TREE_CODE (expression) == SIZEOF_EXPR
12306 || TREE_CODE (expression) == ALIGNOF_EXPR
12307 || TREE_CODE (expression) == TYPEID_EXPR
12308 || TREE_CODE (expression) == DELETE_EXPR
12309 || TREE_CODE (expression) == VEC_DELETE_EXPR
12310 || TREE_CODE (expression) == THROW_EXPR)
12313 /* The types of these expressions depends only on the type to which
12314 the cast occurs. */
12315 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12316 || TREE_CODE (expression) == STATIC_CAST_EXPR
12317 || TREE_CODE (expression) == CONST_CAST_EXPR
12318 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12319 || TREE_CODE (expression) == CAST_EXPR)
12320 return dependent_type_p (TREE_TYPE (expression));
12322 /* The types of these expressions depends only on the type created
12323 by the expression. */
12324 if (TREE_CODE (expression) == NEW_EXPR
12325 || TREE_CODE (expression) == VEC_NEW_EXPR)
12327 /* For NEW_EXPR tree nodes created inside a template, either
12328 the object type itself or a TREE_LIST may appear as the
12330 tree type = TREE_OPERAND (expression, 1);
12331 if (TREE_CODE (type) == TREE_LIST)
12332 /* This is an array type. We need to check array dimensions
12334 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12335 || value_dependent_expression_p
12336 (TREE_OPERAND (TREE_VALUE (type), 1));
12338 return dependent_type_p (type);
12341 if (TREE_CODE (expression) == SCOPE_REF
12342 && dependent_scope_ref_p (expression,
12343 type_dependent_expression_p))
12346 if (TREE_CODE (expression) == FUNCTION_DECL
12347 && DECL_LANG_SPECIFIC (expression)
12348 && DECL_TEMPLATE_INFO (expression)
12349 && (any_dependent_template_arguments_p
12350 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12353 if (TREE_CODE (expression) == TEMPLATE_DECL
12354 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12357 if (TREE_TYPE (expression) == unknown_type_node)
12359 if (TREE_CODE (expression) == ADDR_EXPR)
12360 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12361 if (TREE_CODE (expression) == COMPONENT_REF
12362 || TREE_CODE (expression) == OFFSET_REF)
12364 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12366 expression = TREE_OPERAND (expression, 1);
12367 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12370 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12371 if (TREE_CODE (expression) == SCOPE_REF)
12374 if (TREE_CODE (expression) == BASELINK)
12375 expression = BASELINK_FUNCTIONS (expression);
12377 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12379 if (any_dependent_template_arguments_p
12380 (TREE_OPERAND (expression, 1)))
12382 expression = TREE_OPERAND (expression, 0);
12384 gcc_assert (TREE_CODE (expression) == OVERLOAD
12385 || TREE_CODE (expression) == FUNCTION_DECL);
12389 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12391 expression = OVL_NEXT (expression);
12396 return (dependent_type_p (TREE_TYPE (expression)));
12399 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12400 contains a type-dependent expression. */
12403 any_type_dependent_arguments_p (tree args)
12407 tree arg = TREE_VALUE (args);
12409 if (type_dependent_expression_p (arg))
12411 args = TREE_CHAIN (args);
12416 /* Returns TRUE if the ARG (a template argument) is dependent. */
12419 dependent_template_arg_p (tree arg)
12421 if (!processing_template_decl)
12424 if (TREE_CODE (arg) == TEMPLATE_DECL
12425 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12426 return dependent_template_p (arg);
12427 else if (TYPE_P (arg))
12428 return dependent_type_p (arg);
12430 return (type_dependent_expression_p (arg)
12431 || value_dependent_expression_p (arg));
12434 /* Returns true if ARGS (a collection of template arguments) contains
12435 any dependent arguments. */
12438 any_dependent_template_arguments_p (tree args)
12446 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12448 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12449 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12450 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12457 /* Returns TRUE if the template TMPL is dependent. */
12460 dependent_template_p (tree tmpl)
12462 if (TREE_CODE (tmpl) == OVERLOAD)
12466 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12468 tmpl = OVL_CHAIN (tmpl);
12473 /* Template template parameters are dependent. */
12474 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12475 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12477 /* So are names that have not been looked up. */
12478 if (TREE_CODE (tmpl) == SCOPE_REF
12479 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12481 /* So are member templates of dependent classes. */
12482 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12483 return dependent_type_p (DECL_CONTEXT (tmpl));
12487 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12490 dependent_template_id_p (tree tmpl, tree args)
12492 return (dependent_template_p (tmpl)
12493 || any_dependent_template_arguments_p (args));
12496 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12497 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12498 can be found. Note that this function peers inside uninstantiated
12499 templates and therefore should be used only in extremely limited
12500 situations. ONLY_CURRENT_P restricts this peering to the currently
12501 open classes hierarchy (which is required when comparing types). */
12504 resolve_typename_type (tree type, bool only_current_p)
12512 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12514 scope = TYPE_CONTEXT (type);
12515 name = TYPE_IDENTIFIER (type);
12517 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12518 it first before we can figure out what NAME refers to. */
12519 if (TREE_CODE (scope) == TYPENAME_TYPE)
12520 scope = resolve_typename_type (scope, only_current_p);
12521 /* If we don't know what SCOPE refers to, then we cannot resolve the
12523 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12524 return error_mark_node;
12525 /* If the SCOPE is a template type parameter, we have no way of
12526 resolving the name. */
12527 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12529 /* If the SCOPE is not the current instantiation, there's no reason
12530 to look inside it. */
12531 if (only_current_p && !currently_open_class (scope))
12532 return error_mark_node;
12533 /* If SCOPE is a partial instantiation, it will not have a valid
12534 TYPE_FIELDS list, so use the original template. */
12535 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12536 /* Enter the SCOPE so that name lookup will be resolved as if we
12537 were in the class definition. In particular, SCOPE will no
12538 longer be considered a dependent type. */
12539 pushed_scope = push_scope (scope);
12540 /* Look up the declaration. */
12541 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12542 /* Obtain the set of qualifiers applied to the TYPE. */
12543 quals = cp_type_quals (type);
12544 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12545 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12547 type = error_mark_node;
12548 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12549 && TREE_CODE (decl) == TYPE_DECL)
12550 type = TREE_TYPE (decl);
12551 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12552 && DECL_CLASS_TEMPLATE_P (decl))
12556 /* Obtain the template and the arguments. */
12557 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12558 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12559 /* Instantiate the template. */
12560 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12561 /*entering_scope=*/0, tf_error | tf_user);
12564 type = error_mark_node;
12565 /* Qualify the resulting type. */
12566 if (type != error_mark_node && quals)
12567 type = cp_build_qualified_type (type, quals);
12568 /* Leave the SCOPE. */
12570 pop_scope (pushed_scope);
12575 /* EXPR is an expression which is not type-dependent. Return a proxy
12576 for EXPR that can be used to compute the types of larger
12577 expressions containing EXPR. */
12580 build_non_dependent_expr (tree expr)
12584 /* Preserve null pointer constants so that the type of things like
12585 "p == 0" where "p" is a pointer can be determined. */
12586 if (null_ptr_cst_p (expr))
12588 /* Preserve OVERLOADs; the functions must be available to resolve
12590 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12591 TREE_OPERAND (expr, 0) : expr);
12592 if (is_overloaded_fn (inner_expr)
12593 || TREE_CODE (inner_expr) == OFFSET_REF)
12595 /* There is no need to return a proxy for a variable. */
12596 if (TREE_CODE (expr) == VAR_DECL)
12598 /* Preserve string constants; conversions from string constants to
12599 "char *" are allowed, even though normally a "const char *"
12600 cannot be used to initialize a "char *". */
12601 if (TREE_CODE (expr) == STRING_CST)
12603 /* Preserve arithmetic constants, as an optimization -- there is no
12604 reason to create a new node. */
12605 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12607 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12608 There is at least one place where we want to know that a
12609 particular expression is a throw-expression: when checking a ?:
12610 expression, there are special rules if the second or third
12611 argument is a throw-expression. */
12612 if (TREE_CODE (expr) == THROW_EXPR)
12615 if (TREE_CODE (expr) == COND_EXPR)
12616 return build3 (COND_EXPR,
12618 TREE_OPERAND (expr, 0),
12619 (TREE_OPERAND (expr, 1)
12620 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12621 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12622 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12623 if (TREE_CODE (expr) == COMPOUND_EXPR
12624 && !COMPOUND_EXPR_OVERLOADED (expr))
12625 return build2 (COMPOUND_EXPR,
12627 TREE_OPERAND (expr, 0),
12628 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12630 /* Otherwise, build a NON_DEPENDENT_EXPR.
12632 REFERENCE_TYPEs are not stripped for expressions in templates
12633 because doing so would play havoc with mangling. Consider, for
12636 template <typename T> void f<T& g>() { g(); }
12638 In the body of "f", the expression for "g" will have
12639 REFERENCE_TYPE, even though the standard says that it should
12640 not. The reason is that we must preserve the syntactic form of
12641 the expression so that mangling (say) "f<g>" inside the body of
12642 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12644 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12647 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12648 Return a new TREE_LIST with the various arguments replaced with
12649 equivalent non-dependent expressions. */
12652 build_non_dependent_args (tree args)
12657 new_args = NULL_TREE;
12658 for (a = args; a; a = TREE_CHAIN (a))
12659 new_args = tree_cons (NULL_TREE,
12660 build_non_dependent_expr (TREE_VALUE (a)),
12662 return nreverse (new_args);
12665 #include "gt-cp-pt.h"