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 /* A 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));
3114 /* Perhaps we should also check that the parms are used in the
3115 appropriate qualifying scopes in the declarator? */
3117 if (current == decl)
3120 current = TYPE_CONTEXT (current);
3124 DECL_TEMPLATE_RESULT (tmpl) = decl;
3125 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3127 /* Push template declarations for global functions and types. Note
3128 that we do not try to push a global template friend declared in a
3129 template class; such a thing may well depend on the template
3130 parameters of the class. */
3131 if (new_template_p && !ctx
3132 && !(is_friend && template_class_depth (current_class_type) > 0))
3134 tmpl = pushdecl_namespace_level (tmpl);
3135 if (tmpl == error_mark_node)
3136 return error_mark_node;
3138 /* Hide template friend classes that haven't been declared yet. */
3139 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
3141 DECL_ANTICIPATED (tmpl) = 1;
3142 DECL_FRIEND_P (tmpl) = 1;
3148 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3149 if (DECL_CONV_FN_P (tmpl))
3151 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3153 /* It is a conversion operator. See if the type converted to
3154 depends on innermost template operands. */
3156 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3158 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3162 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3163 back to its most general template. If TMPL is a specialization,
3164 ARGS may only have the innermost set of arguments. Add the missing
3165 argument levels if necessary. */
3166 if (DECL_TEMPLATE_INFO (tmpl))
3167 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3169 info = tree_cons (tmpl, args, NULL_TREE);
3171 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3173 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3174 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3175 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3176 /* Don't change the name if we've already set it up. */
3177 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3178 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3180 else if (DECL_LANG_SPECIFIC (decl))
3181 DECL_TEMPLATE_INFO (decl) = info;
3183 return DECL_TEMPLATE_RESULT (tmpl);
3187 push_template_decl (tree decl)
3189 return push_template_decl_real (decl, 0);
3192 /* Called when a class template TYPE is redeclared with the indicated
3193 template PARMS, e.g.:
3195 template <class T> struct S;
3196 template <class T> struct S {}; */
3199 redeclare_class_template (tree type, tree parms)
3205 if (!TYPE_TEMPLATE_INFO (type))
3207 error ("%qT is not a template type", type);
3211 tmpl = TYPE_TI_TEMPLATE (type);
3212 if (!PRIMARY_TEMPLATE_P (tmpl))
3213 /* The type is nested in some template class. Nothing to worry
3214 about here; there are no new template parameters for the nested
3220 error ("template specifiers not specified in declaration of %qD",
3225 parms = INNERMOST_TEMPLATE_PARMS (parms);
3226 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3228 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3230 error ("previous declaration %q+D", tmpl);
3231 error ("used %d template parameter(s) instead of %d",
3232 TREE_VEC_LENGTH (tmpl_parms),
3233 TREE_VEC_LENGTH (parms));
3237 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3239 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3240 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3241 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3242 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3244 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3246 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3247 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3248 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3250 error ("template parameter %q+#D", tmpl_parm);
3251 error ("redeclared here as %q#D", parm);
3255 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3257 /* We have in [temp.param]:
3259 A template-parameter may not be given default arguments
3260 by two different declarations in the same scope. */
3261 error ("redefinition of default argument for %q#D", parm);
3262 error ("%J original definition appeared here", tmpl_parm);
3266 if (parm_default != NULL_TREE)
3267 /* Update the previous template parameters (which are the ones
3268 that will really count) with the new default value. */
3269 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3270 else if (tmpl_default != NULL_TREE)
3271 /* Update the new parameters, too; they'll be used as the
3272 parameters for any members. */
3273 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3277 /* Simplify EXPR if it is a non-dependent expression. Returns the
3278 (possibly simplified) expression. */
3281 fold_non_dependent_expr (tree expr)
3283 /* If we're in a template, but EXPR isn't value dependent, simplify
3284 it. We're supposed to treat:
3286 template <typename T> void f(T[1 + 1]);
3287 template <typename T> void f(T[2]);
3289 as two declarations of the same function, for example. */
3290 if (processing_template_decl
3291 && !type_dependent_expression_p (expr)
3292 && !value_dependent_expression_p (expr))
3294 HOST_WIDE_INT saved_processing_template_decl;
3296 saved_processing_template_decl = processing_template_decl;
3297 processing_template_decl = 0;
3298 expr = tsubst_copy_and_build (expr,
3301 /*in_decl=*/NULL_TREE,
3302 /*function_p=*/false);
3303 processing_template_decl = saved_processing_template_decl;
3308 /* EXPR is an expression which is used in a constant-expression context.
3309 For instance, it could be a VAR_DECL with a constant initializer.
3310 Extract the innest constant expression.
3312 This is basically a more powerful version of
3313 integral_constant_value, which can be used also in templates where
3314 initializers can maintain a syntactic rather than semantic form
3315 (even if they are non-dependent, for access-checking purposes). */
3318 fold_decl_constant_value (tree expr)
3320 tree const_expr = expr;
3323 expr = fold_non_dependent_expr (const_expr);
3324 const_expr = integral_constant_value (expr);
3326 while (expr != const_expr);
3331 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3332 must be a function or a pointer-to-function type, as specified
3333 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3334 and check that the resulting function has external linkage. */
3337 convert_nontype_argument_function (tree type, tree expr)
3342 fn = instantiate_type (type, fns, tf_none);
3343 if (fn == error_mark_node)
3344 return error_mark_node;
3347 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3348 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3350 /* [temp.arg.nontype]/1
3352 A template-argument for a non-type, non-template template-parameter
3355 -- the address of an object or function with external linkage. */
3356 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3358 error ("%qE is not a valid template argument for type %qT "
3359 "because function %qD has not external linkage",
3360 expr, type, fn_no_ptr);
3367 /* Attempt to convert the non-type template parameter EXPR to the
3368 indicated TYPE. If the conversion is successful, return the
3369 converted value. If the conversion is unsuccessful, return
3370 NULL_TREE if we issued an error message, or error_mark_node if we
3371 did not. We issue error messages for out-and-out bad template
3372 parameters, but not simply because the conversion failed, since we
3373 might be just trying to do argument deduction. Both TYPE and EXPR
3374 must be non-dependent.
3376 The conversion follows the special rules described in
3377 [temp.arg.nontype], and it is much more strict than an implicit
3380 This function is called twice for each template argument (see
3381 lookup_template_class for a more accurate description of this
3382 problem). This means that we need to handle expressions which
3383 are not valid in a C++ source, but can be created from the
3384 first call (for instance, casts to perform conversions). These
3385 hacks can go away after we fix the double coercion problem. */
3388 convert_nontype_argument (tree type, tree expr)
3392 /* Detect immediately string literals as invalid non-type argument.
3393 This special-case is not needed for correctness (we would easily
3394 catch this later), but only to provide better diagnostic for this
3395 common user mistake. As suggested by DR 100, we do not mention
3396 linkage issues in the diagnostic as this is not the point. */
3397 if (TREE_CODE (expr) == STRING_CST)
3399 error ("%qE is not a valid template argument for type %qT "
3400 "because string literals can never be used in this context",
3405 /* If we are in a template, EXPR may be non-dependent, but still
3406 have a syntactic, rather than semantic, form. For example, EXPR
3407 might be a SCOPE_REF, rather than the VAR_DECL to which the
3408 SCOPE_REF refers. Preserving the qualifying scope is necessary
3409 so that access checking can be performed when the template is
3410 instantiated -- but here we need the resolved form so that we can
3411 convert the argument. */
3412 expr = fold_non_dependent_expr (expr);
3413 expr_type = TREE_TYPE (expr);
3415 /* HACK: Due to double coercion, we can get a
3416 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3417 which is the tree that we built on the first call (see
3418 below when coercing to reference to object or to reference to
3419 function). We just strip everything and get to the arg.
3420 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3422 if (TREE_CODE (expr) == NOP_EXPR)
3424 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3426 /* ??? Maybe we could use convert_from_reference here, but we
3427 would need to relax its constraints because the NOP_EXPR
3428 could actually change the type to something more cv-qualified,
3429 and this is not folded by convert_from_reference. */
3430 tree addr = TREE_OPERAND (expr, 0);
3431 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3432 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3433 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3434 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3435 (TREE_TYPE (expr_type),
3436 TREE_TYPE (TREE_TYPE (addr))));
3438 expr = TREE_OPERAND (addr, 0);
3439 expr_type = TREE_TYPE (expr);
3442 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3443 parameter is a pointer to object, through decay and
3444 qualification conversion. Let's strip everything. */
3445 else if (TYPE_PTROBV_P (type))
3448 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3449 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3450 /* Skip the ADDR_EXPR only if it is part of the decay for
3451 an array. Otherwise, it is part of the original argument
3452 in the source code. */
3453 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3454 expr = TREE_OPERAND (expr, 0);
3455 expr_type = TREE_TYPE (expr);
3459 /* [temp.arg.nontype]/5, bullet 1
3461 For a non-type template-parameter of integral or enumeration type,
3462 integral promotions (_conv.prom_) and integral conversions
3463 (_conv.integral_) are applied. */
3464 if (INTEGRAL_TYPE_P (type))
3466 if (!INTEGRAL_TYPE_P (expr_type))
3467 return error_mark_node;
3469 expr = fold_decl_constant_value (expr);
3470 /* Notice that there are constant expressions like '4 % 0' which
3471 do not fold into integer constants. */
3472 if (TREE_CODE (expr) != INTEGER_CST)
3474 error ("%qE is not a valid template argument for type %qT "
3475 "because it is a non-constant expression", expr, type);
3479 /* At this point, an implicit conversion does what we want,
3480 because we already know that the expression is of integral
3482 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3483 if (expr == error_mark_node)
3484 return error_mark_node;
3486 /* Conversion was allowed: fold it to a bare integer constant. */
3489 /* [temp.arg.nontype]/5, bullet 2
3491 For a non-type template-parameter of type pointer to object,
3492 qualification conversions (_conv.qual_) and the array-to-pointer
3493 conversion (_conv.array_) are applied. */
3494 else if (TYPE_PTROBV_P (type))
3496 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3498 A template-argument for a non-type, non-template template-parameter
3499 shall be one of: [...]
3501 -- the name of a non-type template-parameter;
3502 -- the address of an object or function with external linkage, [...]
3503 expressed as "& id-expression" where the & is optional if the name
3504 refers to a function or array, or if the corresponding
3505 template-parameter is a reference.
3507 Here, we do not care about functions, as they are invalid anyway
3508 for a parameter of type pointer-to-object. */
3509 bool constant_address_p =
3510 (TREE_CODE (expr) == ADDR_EXPR
3511 || TREE_CODE (expr_type) == ARRAY_TYPE
3512 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3514 expr = decay_conversion (expr);
3515 if (expr == error_mark_node)
3516 return error_mark_node;
3518 expr = perform_qualification_conversions (type, expr);
3519 if (expr == error_mark_node)
3520 return error_mark_node;
3522 if (!constant_address_p)
3524 error ("%qE is not a valid template argument for type %qT "
3525 "because it is not a constant pointer", expr, type);
3529 /* [temp.arg.nontype]/5, bullet 3
3531 For a non-type template-parameter of type reference to object, no
3532 conversions apply. The type referred to by the reference may be more
3533 cv-qualified than the (otherwise identical) type of the
3534 template-argument. The template-parameter is bound directly to the
3535 template-argument, which must be an lvalue. */
3536 else if (TYPE_REF_OBJ_P (type))
3538 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3540 return error_mark_node;
3542 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3544 error ("%qE is not a valid template argument for type %qT "
3545 "because of conflicts in cv-qualification", expr, type);
3549 if (!real_lvalue_p (expr))
3551 error ("%qE is not a valid template argument for type %qT "
3552 "because it is not a lvalue", expr, type);
3556 /* [temp.arg.nontype]/1
3558 A template-argument for a non-type, non-template template-parameter
3559 shall be one of: [...]
3561 -- the address of an object or function with external linkage. */
3562 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3564 error ("%qE is not a valid template argument for type %qT "
3565 "because object %qD has not external linkage",
3570 expr = build_nop (type, build_address (expr));
3572 /* [temp.arg.nontype]/5, bullet 4
3574 For a non-type template-parameter of type pointer to function, only
3575 the function-to-pointer conversion (_conv.func_) is applied. If the
3576 template-argument represents a set of overloaded functions (or a
3577 pointer to such), the matching function is selected from the set
3579 else if (TYPE_PTRFN_P (type))
3581 /* If the argument is a template-id, we might not have enough
3582 context information to decay the pointer.
3583 ??? Why static5.C requires decay and subst1.C works fine
3585 if (!type_unknown_p (expr_type))
3587 expr = decay_conversion (expr);
3588 if (expr == error_mark_node)
3589 return error_mark_node;
3592 expr = convert_nontype_argument_function (type, expr);
3593 if (!expr || expr == error_mark_node)
3596 /* [temp.arg.nontype]/5, bullet 5
3598 For a non-type template-parameter of type reference to function, no
3599 conversions apply. If the template-argument represents a set of
3600 overloaded functions, the matching function is selected from the set
3602 else if (TYPE_REFFN_P (type))
3604 if (TREE_CODE (expr) == ADDR_EXPR)
3606 error ("%qE is not a valid template argument for type %qT "
3607 "because it is a pointer", expr, type);
3608 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3612 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3613 if (!expr || expr == error_mark_node)
3616 expr = build_nop (type, build_address (expr));
3618 /* [temp.arg.nontype]/5, bullet 6
3620 For a non-type template-parameter of type pointer to member function,
3621 no conversions apply. If the template-argument represents a set of
3622 overloaded member functions, the matching member function is selected
3623 from the set (_over.over_). */
3624 else if (TYPE_PTRMEMFUNC_P (type))
3626 expr = instantiate_type (type, expr, tf_none);
3627 if (expr == error_mark_node)
3628 return error_mark_node;
3630 /* There is no way to disable standard conversions in
3631 resolve_address_of_overloaded_function (called by
3632 instantiate_type). It is possible that the call succeeded by
3633 converting &B::I to &D::I (where B is a base of D), so we need
3634 to reject this conversion here.
3636 Actually, even if there was a way to disable standard conversions,
3637 it would still be better to reject them here so that we can
3638 provide a superior diagnostic. */
3639 if (!same_type_p (TREE_TYPE (expr), type))
3641 /* Make sure we are just one standard conversion off. */
3642 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3643 error ("%qE is not a valid template argument for type %qT "
3644 "because it is of type %qT", expr, type,
3646 inform ("standard conversions are not allowed in this context");
3650 /* [temp.arg.nontype]/5, bullet 7
3652 For a non-type template-parameter of type pointer to data member,
3653 qualification conversions (_conv.qual_) are applied. */
3654 else if (TYPE_PTRMEM_P (type))
3656 expr = perform_qualification_conversions (type, expr);
3657 if (expr == error_mark_node)
3660 /* A template non-type parameter must be one of the above. */
3664 /* Sanity check: did we actually convert the argument to the
3666 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3671 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3672 template template parameters. Both PARM_PARMS and ARG_PARMS are
3673 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3676 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3677 the case, then extra parameters must have default arguments.
3679 Consider the example:
3680 template <class T, class Allocator = allocator> class vector;
3681 template<template <class U> class TT> class C;
3683 C<vector> is a valid instantiation. PARM_PARMS for the above code
3684 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3685 T and Allocator) and OUTER_ARGS contains the argument that is used to
3686 substitute the TT parameter. */
3689 coerce_template_template_parms (tree parm_parms,
3691 tsubst_flags_t complain,
3695 int nparms, nargs, i;
3698 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3699 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3701 nparms = TREE_VEC_LENGTH (parm_parms);
3702 nargs = TREE_VEC_LENGTH (arg_parms);
3704 /* The rule here is opposite of coerce_template_parms. */
3707 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3710 for (i = 0; i < nparms; ++i)
3712 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3713 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3715 if (arg == NULL_TREE || arg == error_mark_node
3716 || parm == NULL_TREE || parm == error_mark_node)
3719 if (TREE_CODE (arg) != TREE_CODE (parm))
3722 switch (TREE_CODE (parm))
3728 /* We encounter instantiations of templates like
3729 template <template <template <class> class> class TT>
3732 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3733 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3735 if (!coerce_template_template_parms
3736 (parmparm, argparm, complain, in_decl, outer_args))
3742 /* The tsubst call is used to handle cases such as
3744 template <int> class C {};
3745 template <class T, template <T> class TT> class D {};
3748 i.e. the parameter list of TT depends on earlier parameters. */
3749 if (!dependent_type_p (TREE_TYPE (arg))
3751 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3763 /* Convert the indicated template ARG as necessary to match the
3764 indicated template PARM. Returns the converted ARG, or
3765 error_mark_node if the conversion was unsuccessful. Error and
3766 warning messages are issued under control of COMPLAIN. This
3767 conversion is for the Ith parameter in the parameter list. ARGS is
3768 the full set of template arguments deduced so far. */
3771 convert_template_argument (tree parm,
3774 tsubst_flags_t complain,
3780 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3782 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3784 if (TREE_CODE (arg) == TREE_LIST
3785 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3787 /* The template argument was the name of some
3788 member function. That's usually
3789 invalid, but static members are OK. In any
3790 case, grab the underlying fields/functions
3791 and issue an error later if required. */
3792 arg = TREE_VALUE (arg);
3793 TREE_TYPE (arg) = unknown_type_node;
3796 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3797 requires_type = (TREE_CODE (parm) == TYPE_DECL
3798 || requires_tmpl_type);
3800 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3801 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3802 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3803 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3806 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3807 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3808 arg = TYPE_STUB_DECL (arg);
3810 is_type = TYPE_P (arg) || is_tmpl_type;
3812 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3813 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3815 pedwarn ("to refer to a type member of a template parameter, "
3816 "use %<typename %E%>", arg);
3818 arg = make_typename_type (TREE_OPERAND (arg, 0),
3819 TREE_OPERAND (arg, 1),
3821 complain & tf_error);
3824 if (is_type != requires_type)
3828 if (complain & tf_error)
3830 error ("type/value mismatch at argument %d in template "
3831 "parameter list for %qD",
3834 error (" expected a constant of type %qT, got %qT",
3836 (is_tmpl_type ? DECL_NAME (arg) : arg));
3837 else if (requires_tmpl_type)
3838 error (" expected a class template, got %qE", arg);
3840 error (" expected a type, got %qE", arg);
3843 return error_mark_node;
3845 if (is_tmpl_type ^ requires_tmpl_type)
3847 if (in_decl && (complain & tf_error))
3849 error ("type/value mismatch at argument %d in template "
3850 "parameter list for %qD",
3853 error (" expected a type, got %qT", DECL_NAME (arg));
3855 error (" expected a class template, got %qT", arg);
3857 return error_mark_node;
3862 if (requires_tmpl_type)
3864 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3865 /* The number of argument required is not known yet.
3866 Just accept it for now. */
3867 val = TREE_TYPE (arg);
3870 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3871 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3873 if (coerce_template_template_parms (parmparm, argparm,
3879 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3881 if (val != error_mark_node
3882 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3883 val = TREE_TYPE (val);
3887 if (in_decl && (complain & tf_error))
3889 error ("type/value mismatch at argument %d in "
3890 "template parameter list for %qD",
3892 error (" expected a template of type %qD, got %qD",
3896 val = error_mark_node;
3905 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3907 if (invalid_nontype_parm_type_p (t, complain))
3908 return error_mark_node;
3910 if (!uses_template_parms (arg) && !uses_template_parms (t))
3911 /* We used to call digest_init here. However, digest_init
3912 will report errors, which we don't want when complain
3913 is zero. More importantly, digest_init will try too
3914 hard to convert things: for example, `0' should not be
3915 converted to pointer type at this point according to
3916 the standard. Accepting this is not merely an
3917 extension, since deciding whether or not these
3918 conversions can occur is part of determining which
3919 function template to call, or whether a given explicit
3920 argument specification is valid. */
3921 val = convert_nontype_argument (t, arg);
3925 if (val == NULL_TREE)
3926 val = error_mark_node;
3927 else if (val == error_mark_node && (complain & tf_error))
3928 error ("could not convert template argument %qE to %qT", arg, t);
3934 /* Convert all template arguments to their appropriate types, and
3935 return a vector containing the innermost resulting template
3936 arguments. If any error occurs, return error_mark_node. Error and
3937 warning messages are issued under control of COMPLAIN.
3939 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3940 provided in ARGLIST, or else trailing parameters must have default
3941 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3942 deduction for any unspecified trailing arguments. */
3945 coerce_template_parms (tree parms,
3948 tsubst_flags_t complain,
3949 int require_all_arguments)
3951 int nparms, nargs, i, lost = 0;
3954 tree new_inner_args;
3956 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3957 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3958 nparms = TREE_VEC_LENGTH (parms);
3962 && require_all_arguments
3963 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3965 if (complain & tf_error)
3967 error ("wrong number of template arguments (%d, should be %d)",
3971 error ("provided for %q+D", in_decl);
3974 return error_mark_node;
3977 new_inner_args = make_tree_vec (nparms);
3978 new_args = add_outermost_template_args (args, new_inner_args);
3979 for (i = 0; i < nparms; i++)
3984 /* Get the Ith template parameter. */
3985 parm = TREE_VEC_ELT (parms, i);
3987 /* Calculate the Ith argument. */
3989 arg = TREE_VEC_ELT (inner_args, i);
3990 else if (require_all_arguments)
3991 /* There must be a default arg in this case. */
3992 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
3998 if (arg == error_mark_node)
4000 if (complain & tf_error)
4001 error ("template argument %d is invalid", i + 1);
4004 arg = convert_template_argument (TREE_VALUE (parm),
4005 arg, new_args, complain, i,
4008 if (arg == error_mark_node)
4010 TREE_VEC_ELT (new_inner_args, i) = arg;
4014 return error_mark_node;
4016 return new_inner_args;
4019 /* Returns 1 if template args OT and NT are equivalent. */
4022 template_args_equal (tree ot, tree nt)
4027 if (TREE_CODE (nt) == TREE_VEC)
4028 /* For member templates */
4029 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4030 else if (TYPE_P (nt))
4031 return TYPE_P (ot) && same_type_p (ot, nt);
4032 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4035 return cp_tree_equal (ot, nt);
4038 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4039 of template arguments. Returns 0 otherwise. */
4042 comp_template_args (tree oldargs, tree newargs)
4046 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4049 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4051 tree nt = TREE_VEC_ELT (newargs, i);
4052 tree ot = TREE_VEC_ELT (oldargs, i);
4054 if (! template_args_equal (ot, nt))
4060 /* Given class template name and parameter list, produce a user-friendly name
4061 for the instantiation. */
4064 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4066 static struct obstack scratch_obstack;
4067 static char *scratch_firstobj;
4070 if (!scratch_firstobj)
4071 gcc_obstack_init (&scratch_obstack);
4073 obstack_free (&scratch_obstack, scratch_firstobj);
4074 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4076 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4077 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4081 nparms = TREE_VEC_LENGTH (parms);
4082 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4083 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4084 for (i = 0; i < nparms; i++)
4086 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4087 tree arg = TREE_VEC_ELT (arglist, i);
4092 if (TREE_CODE (parm) == TYPE_DECL)
4094 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4097 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4099 if (TREE_CODE (arg) == TEMPLATE_DECL)
4101 /* Already substituted with real template. Just output
4102 the template name here */
4103 tree context = DECL_CONTEXT (arg);
4106 /* The template may be defined in a namespace, or
4107 may be a member template. */
4108 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4109 || CLASS_TYPE_P (context));
4110 cat (decl_as_string (DECL_CONTEXT (arg),
4111 TFF_PLAIN_IDENTIFIER));
4114 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4117 /* Output the parameter declaration. */
4118 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4122 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4124 /* No need to check arglist against parmlist here; we did that
4125 in coerce_template_parms, called from lookup_template_class. */
4126 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4129 char *bufp = obstack_next_free (&scratch_obstack);
4131 while (bufp[offset - 1] == ' ')
4133 obstack_blank_fast (&scratch_obstack, offset);
4135 /* B<C<char> >, not B<C<char>> */
4136 if (bufp[offset - 1] == '>')
4141 return (char *) obstack_base (&scratch_obstack);
4145 classtype_mangled_name (tree t)
4147 if (CLASSTYPE_TEMPLATE_INFO (t)
4148 /* Specializations have already had their names set up in
4149 lookup_template_class. */
4150 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4152 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4154 /* For non-primary templates, the template parameters are
4155 implicit from their surrounding context. */
4156 if (PRIMARY_TEMPLATE_P (tmpl))
4158 tree name = DECL_NAME (tmpl);
4159 char *mangled_name = mangle_class_name_for_template
4160 (IDENTIFIER_POINTER (name),
4161 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4162 CLASSTYPE_TI_ARGS (t));
4163 tree id = get_identifier (mangled_name);
4164 IDENTIFIER_TEMPLATE (id) = name;
4169 return TYPE_IDENTIFIER (t);
4173 add_pending_template (tree d)
4175 tree ti = (TYPE_P (d)
4176 ? CLASSTYPE_TEMPLATE_INFO (d)
4177 : DECL_TEMPLATE_INFO (d));
4181 if (TI_PENDING_TEMPLATE_FLAG (ti))
4184 /* We are called both from instantiate_decl, where we've already had a
4185 tinst_level pushed, and instantiate_template, where we haven't.
4187 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4190 push_tinst_level (d);
4192 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4193 if (last_pending_template)
4194 TREE_CHAIN (last_pending_template) = pt;
4196 pending_templates = pt;
4198 last_pending_template = pt;
4200 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4207 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4208 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4209 documentation for TEMPLATE_ID_EXPR. */
4212 lookup_template_function (tree fns, tree arglist)
4216 if (fns == error_mark_node || arglist == error_mark_node)
4217 return error_mark_node;
4219 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4220 gcc_assert (fns && (is_overloaded_fn (fns)
4221 || TREE_CODE (fns) == IDENTIFIER_NODE));
4223 if (BASELINK_P (fns))
4225 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4227 BASELINK_FUNCTIONS (fns),
4232 type = TREE_TYPE (fns);
4233 if (TREE_CODE (fns) == OVERLOAD || !type)
4234 type = unknown_type_node;
4236 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4239 /* Within the scope of a template class S<T>, the name S gets bound
4240 (in build_self_reference) to a TYPE_DECL for the class, not a
4241 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4242 or one of its enclosing classes, and that type is a template,
4243 return the associated TEMPLATE_DECL. Otherwise, the original
4244 DECL is returned. */
4247 maybe_get_template_decl_from_type_decl (tree decl)
4249 return (decl != NULL_TREE
4250 && TREE_CODE (decl) == TYPE_DECL
4251 && DECL_ARTIFICIAL (decl)
4252 && CLASS_TYPE_P (TREE_TYPE (decl))
4253 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4254 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4257 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4258 parameters, find the desired type.
4260 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4262 IN_DECL, if non-NULL, is the template declaration we are trying to
4265 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4266 the class we are looking up.
4268 Issue error and warning messages under control of COMPLAIN.
4270 If the template class is really a local class in a template
4271 function, then the FUNCTION_CONTEXT is the function in which it is
4274 ??? Note that this function is currently called *twice* for each
4275 template-id: the first time from the parser, while creating the
4276 incomplete type (finish_template_type), and the second type during the
4277 real instantiation (instantiate_template_class). This is surely something
4278 that we want to avoid. It also causes some problems with argument
4279 coercion (see convert_nontype_argument for more information on this). */
4282 lookup_template_class (tree d1,
4287 tsubst_flags_t complain)
4289 tree template = NULL_TREE, parmlist;
4292 timevar_push (TV_NAME_LOOKUP);
4294 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4296 tree value = innermost_non_namespace_value (d1);
4297 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4302 push_decl_namespace (context);
4303 template = lookup_name (d1, /*prefer_type=*/0);
4304 template = maybe_get_template_decl_from_type_decl (template);
4306 pop_decl_namespace ();
4309 context = DECL_CONTEXT (template);
4311 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4313 tree type = TREE_TYPE (d1);
4315 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4316 an implicit typename for the second A. Deal with it. */
4317 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4318 type = TREE_TYPE (type);
4320 if (CLASSTYPE_TEMPLATE_INFO (type))
4322 template = CLASSTYPE_TI_TEMPLATE (type);
4323 d1 = DECL_NAME (template);
4326 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4327 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4329 template = TYPE_TI_TEMPLATE (d1);
4330 d1 = DECL_NAME (template);
4332 else if (TREE_CODE (d1) == TEMPLATE_DECL
4333 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4336 d1 = DECL_NAME (template);
4337 context = DECL_CONTEXT (template);
4340 /* Issue an error message if we didn't find a template. */
4343 if (complain & tf_error)
4344 error ("%qT is not a template", d1);
4345 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4348 if (TREE_CODE (template) != TEMPLATE_DECL
4349 /* Make sure it's a user visible template, if it was named by
4351 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4352 && !PRIMARY_TEMPLATE_P (template)))
4354 if (complain & tf_error)
4356 error ("non-template type %qT used as a template", d1);
4358 error ("for template declaration %q+D", in_decl);
4360 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4363 complain &= ~tf_user;
4365 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4367 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4368 template arguments */
4373 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4375 /* Consider an example where a template template parameter declared as
4377 template <class T, class U = std::allocator<T> > class TT
4379 The template parameter level of T and U are one level larger than
4380 of TT. To proper process the default argument of U, say when an
4381 instantiation `TT<int>' is seen, we need to build the full
4382 arguments containing {int} as the innermost level. Outer levels,
4383 available when not appearing as default template argument, can be
4384 obtained from `current_template_args ()'.
4386 Suppose that TT is later substituted with std::vector. The above
4387 instantiation is `TT<int, std::allocator<T> >' with TT at
4388 level 1, and T at level 2, while the template arguments at level 1
4389 becomes {std::vector} and the inner level 2 is {int}. */
4391 if (current_template_parms)
4392 arglist = add_to_template_args (current_template_args (), arglist);
4394 arglist2 = coerce_template_parms (parmlist, arglist, template,
4395 complain, /*require_all_args=*/1);
4396 if (arglist2 == error_mark_node
4397 || (!uses_template_parms (arglist2)
4398 && check_instantiated_args (template, arglist2, complain)))
4399 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4401 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4402 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4406 tree template_type = TREE_TYPE (template);
4409 tree found = NULL_TREE;
4412 int is_partial_instantiation;
4414 gen_tmpl = most_general_template (template);
4415 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4416 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4417 arg_depth = TMPL_ARGS_DEPTH (arglist);
4419 if (arg_depth == 1 && parm_depth > 1)
4421 /* We've been given an incomplete set of template arguments.
4424 template <class T> struct S1 {
4425 template <class U> struct S2 {};
4426 template <class U> struct S2<U*> {};
4429 we will be called with an ARGLIST of `U*', but the
4430 TEMPLATE will be `template <class T> template
4431 <class U> struct S1<T>::S2'. We must fill in the missing
4434 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4436 arg_depth = TMPL_ARGS_DEPTH (arglist);
4439 /* Now we should have enough arguments. */
4440 gcc_assert (parm_depth == arg_depth);
4442 /* From here on, we're only interested in the most general
4444 template = gen_tmpl;
4446 /* Calculate the BOUND_ARGS. These will be the args that are
4447 actually tsubst'd into the definition to create the
4451 /* We have multiple levels of arguments to coerce, at once. */
4453 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4455 tree bound_args = make_tree_vec (parm_depth);
4457 for (i = saved_depth,
4458 t = DECL_TEMPLATE_PARMS (template);
4459 i > 0 && t != NULL_TREE;
4460 --i, t = TREE_CHAIN (t))
4462 tree a = coerce_template_parms (TREE_VALUE (t),
4464 complain, /*require_all_args=*/1);
4466 /* Don't process further if one of the levels fails. */
4467 if (a == error_mark_node)
4469 /* Restore the ARGLIST to its full size. */
4470 TREE_VEC_LENGTH (arglist) = saved_depth;
4471 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4474 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4476 /* We temporarily reduce the length of the ARGLIST so
4477 that coerce_template_parms will see only the arguments
4478 corresponding to the template parameters it is
4480 TREE_VEC_LENGTH (arglist)--;
4483 /* Restore the ARGLIST to its full size. */
4484 TREE_VEC_LENGTH (arglist) = saved_depth;
4486 arglist = bound_args;
4490 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4491 INNERMOST_TEMPLATE_ARGS (arglist),
4493 complain, /*require_all_args=*/1);
4495 if (arglist == error_mark_node)
4496 /* We were unable to bind the arguments. */
4497 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4499 /* In the scope of a template class, explicit references to the
4500 template class refer to the type of the template, not any
4501 instantiation of it. For example, in:
4503 template <class T> class C { void f(C<T>); }
4505 the `C<T>' is just the same as `C'. Outside of the
4506 class, however, such a reference is an instantiation. */
4507 if (comp_template_args (TYPE_TI_ARGS (template_type),
4510 found = template_type;
4512 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4516 for (ctx = current_class_type;
4517 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4519 ? TYPE_CONTEXT (ctx)
4520 : DECL_CONTEXT (ctx)))
4521 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4524 /* We're not in the scope of the class, so the
4525 TEMPLATE_TYPE is not the type we want after all. */
4531 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4533 /* If we already have this specialization, return it. */
4534 found = retrieve_specialization (template, arglist,
4535 /*class_specializations_p=*/false);
4537 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4539 /* This type is a "partial instantiation" if any of the template
4540 arguments still involve template parameters. Note that we set
4541 IS_PARTIAL_INSTANTIATION for partial specializations as
4543 is_partial_instantiation = uses_template_parms (arglist);
4545 /* If the deduced arguments are invalid, then the binding
4547 if (!is_partial_instantiation
4548 && check_instantiated_args (template,
4549 INNERMOST_TEMPLATE_ARGS (arglist),
4551 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4553 if (!is_partial_instantiation
4554 && !PRIMARY_TEMPLATE_P (template)
4555 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4557 found = xref_tag_from_type (TREE_TYPE (template),
4558 DECL_NAME (template),
4559 /*tag_scope=*/ts_global);
4560 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4563 context = tsubst (DECL_CONTEXT (template), arglist,
4566 context = global_namespace;
4568 /* Create the type. */
4569 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4571 if (!is_partial_instantiation)
4573 set_current_access_from_decl (TYPE_NAME (template_type));
4574 t = start_enum (TYPE_IDENTIFIER (template_type));
4577 /* We don't want to call start_enum for this type, since
4578 the values for the enumeration constants may involve
4579 template parameters. And, no one should be interested
4580 in the enumeration constants for such a type. */
4581 t = make_node (ENUMERAL_TYPE);
4585 t = make_aggr_type (TREE_CODE (template_type));
4586 CLASSTYPE_DECLARED_CLASS (t)
4587 = CLASSTYPE_DECLARED_CLASS (template_type);
4588 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4589 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4591 /* A local class. Make sure the decl gets registered properly. */
4592 if (context == current_function_decl)
4593 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
4596 /* If we called start_enum or pushtag above, this information
4597 will already be set up. */
4600 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4602 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4603 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4604 TYPE_STUB_DECL (t) = type_decl;
4605 DECL_SOURCE_LOCATION (type_decl)
4606 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4609 type_decl = TYPE_NAME (t);
4611 TREE_PRIVATE (type_decl)
4612 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4613 TREE_PROTECTED (type_decl)
4614 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4615 DECL_IN_SYSTEM_HEADER (type_decl)
4616 = DECL_IN_SYSTEM_HEADER (template);
4617 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
4619 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
4620 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
4623 /* Set up the template information. We have to figure out which
4624 template is the immediate parent if this is a full
4626 if (parm_depth == 1 || is_partial_instantiation
4627 || !PRIMARY_TEMPLATE_P (template))
4628 /* This case is easy; there are no member templates involved. */
4632 /* This is a full instantiation of a member template. Look
4633 for a partial instantiation of which this is an instance. */
4635 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4636 found; found = TREE_CHAIN (found))
4639 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4641 /* We only want partial instantiations, here, not
4642 specializations or full instantiations. */
4643 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4644 || !uses_template_parms (TREE_VALUE (found)))
4647 /* Temporarily reduce by one the number of levels in the
4648 ARGLIST and in FOUND so as to avoid comparing the
4649 last set of arguments. */
4650 TREE_VEC_LENGTH (arglist)--;
4651 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4653 /* See if the arguments match. If they do, then TMPL is
4654 the partial instantiation we want. */
4655 success = comp_template_args (TREE_PURPOSE (found), arglist);
4657 /* Restore the argument vectors to their full size. */
4658 TREE_VEC_LENGTH (arglist)++;
4659 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4670 /* There was no partial instantiation. This happens
4671 where C<T> is a member template of A<T> and it's used
4674 template <typename T> struct B { A<T>::C<int> m; };
4677 Create the partial instantiation.
4679 TREE_VEC_LENGTH (arglist)--;
4680 found = tsubst (template, arglist, complain, NULL_TREE);
4681 TREE_VEC_LENGTH (arglist)++;
4685 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4686 DECL_TEMPLATE_INSTANTIATIONS (template)
4687 = tree_cons (arglist, t,
4688 DECL_TEMPLATE_INSTANTIATIONS (template));
4690 if (TREE_CODE (t) == ENUMERAL_TYPE
4691 && !is_partial_instantiation)
4692 /* Now that the type has been registered on the instantiations
4693 list, we set up the enumerators. Because the enumeration
4694 constants may involve the enumeration type itself, we make
4695 sure to register the type first, and then create the
4696 constants. That way, doing tsubst_expr for the enumeration
4697 constants won't result in recursive calls here; we'll find
4698 the instantiation and exit above. */
4699 tsubst_enum (template_type, t, arglist);
4701 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4703 if (TREE_CODE (t) != ENUMERAL_TYPE)
4704 DECL_NAME (type_decl) = classtype_mangled_name (t);
4705 if (is_partial_instantiation)
4706 /* If the type makes use of template parameters, the
4707 code that generates debugging information will crash. */
4708 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4710 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4712 timevar_pop (TV_NAME_LOOKUP);
4719 struct pointer_set_t *visited;
4722 /* Called from for_each_template_parm via walk_tree. */
4725 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4728 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4729 tree_fn_t fn = pfd->fn;
4730 void *data = pfd->data;
4733 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4734 return error_mark_node;
4736 switch (TREE_CODE (t))
4739 if (TYPE_PTRMEMFUNC_P (t))
4745 if (!TYPE_TEMPLATE_INFO (t))
4747 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4748 fn, data, pfd->visited))
4749 return error_mark_node;
4753 /* Since we're not going to walk subtrees, we have to do this
4755 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4757 return error_mark_node;
4761 /* Check the return type. */
4762 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4763 return error_mark_node;
4765 /* Check the parameter types. Since default arguments are not
4766 instantiated until they are needed, the TYPE_ARG_TYPES may
4767 contain expressions that involve template parameters. But,
4768 no-one should be looking at them yet. And, once they're
4769 instantiated, they don't contain template parameters, so
4770 there's no point in looking at them then, either. */
4774 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4775 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4777 return error_mark_node;
4779 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4780 want walk_tree walking into them itself. */
4786 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4788 return error_mark_node;
4793 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4794 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4796 return error_mark_node;
4801 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4802 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4804 return error_mark_node;
4805 if (DECL_CONTEXT (t)
4806 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4808 return error_mark_node;
4811 case BOUND_TEMPLATE_TEMPLATE_PARM:
4812 /* Record template parameters such as `T' inside `TT<T>'. */
4813 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4814 return error_mark_node;
4817 case TEMPLATE_TEMPLATE_PARM:
4818 case TEMPLATE_TYPE_PARM:
4819 case TEMPLATE_PARM_INDEX:
4820 if (fn && (*fn)(t, data))
4821 return error_mark_node;
4823 return error_mark_node;
4827 /* A template template parameter is encountered. */
4828 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4829 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4830 return error_mark_node;
4832 /* Already substituted template template parameter */
4838 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4839 data, pfd->visited))
4840 return error_mark_node;
4844 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4845 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4846 (TREE_TYPE (t)), fn, data,
4848 return error_mark_node;
4853 /* If there's no type, then this thing must be some expression
4854 involving template parameters. */
4855 if (!fn && !TREE_TYPE (t))
4856 return error_mark_node;
4861 case REINTERPRET_CAST_EXPR:
4862 case CONST_CAST_EXPR:
4863 case STATIC_CAST_EXPR:
4864 case DYNAMIC_CAST_EXPR:
4868 case PSEUDO_DTOR_EXPR:
4870 return error_mark_node;
4874 /* If we do not handle this case specially, we end up walking
4875 the BINFO hierarchy, which is circular, and therefore
4876 confuses walk_tree. */
4878 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4880 return error_mark_node;
4887 /* We didn't find any template parameters we liked. */
4891 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4892 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4893 call FN with the parameter and the DATA.
4894 If FN returns nonzero, the iteration is terminated, and
4895 for_each_template_parm returns 1. Otherwise, the iteration
4896 continues. If FN never returns a nonzero value, the value
4897 returned by for_each_template_parm is 0. If FN is NULL, it is
4898 considered to be the function which always returns 1. */
4901 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4902 struct pointer_set_t *visited)
4904 struct pair_fn_data pfd;
4911 /* Walk the tree. (Conceptually, we would like to walk without
4912 duplicates, but for_each_template_parm_r recursively calls
4913 for_each_template_parm, so we would need to reorganize a fair
4914 bit to use walk_tree_without_duplicates, so we keep our own
4917 pfd.visited = visited;
4919 pfd.visited = pointer_set_create ();
4920 result = walk_tree (&t,
4921 for_each_template_parm_r,
4923 pfd.visited) != NULL_TREE;
4928 pointer_set_destroy (pfd.visited);
4935 /* Returns true if T depends on any template parameter. */
4938 uses_template_parms (tree t)
4941 int saved_processing_template_decl;
4943 saved_processing_template_decl = processing_template_decl;
4944 if (!saved_processing_template_decl)
4945 processing_template_decl = 1;
4947 dependent_p = dependent_type_p (t);
4948 else if (TREE_CODE (t) == TREE_VEC)
4949 dependent_p = any_dependent_template_arguments_p (t);
4950 else if (TREE_CODE (t) == TREE_LIST)
4951 dependent_p = (uses_template_parms (TREE_VALUE (t))
4952 || uses_template_parms (TREE_CHAIN (t)));
4955 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4956 || TREE_CODE (t) == OVERLOAD
4957 || TREE_CODE (t) == BASELINK
4958 || CONSTANT_CLASS_P (t))
4959 dependent_p = (type_dependent_expression_p (t)
4960 || value_dependent_expression_p (t));
4963 gcc_assert (t == error_mark_node);
4964 dependent_p = false;
4967 processing_template_decl = saved_processing_template_decl;
4972 /* Returns true if T depends on any template parameter with level LEVEL. */
4975 uses_template_parms_level (tree t, int level)
4977 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
4980 static int tinst_depth;
4981 extern int max_tinst_depth;
4982 #ifdef GATHER_STATISTICS
4985 static int tinst_level_tick;
4986 static int last_template_error_tick;
4988 /* We're starting to instantiate D; record the template instantiation context
4989 for diagnostics and to restore it later. */
4992 push_tinst_level (tree d)
4996 if (tinst_depth >= max_tinst_depth)
4998 /* If the instantiation in question still has unbound template parms,
4999 we don't really care if we can't instantiate it, so just return.
5000 This happens with base instantiation for implicit `typename'. */
5001 if (uses_template_parms (d))
5004 last_template_error_tick = tinst_level_tick;
5005 error ("template instantiation depth exceeds maximum of %d (use "
5006 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5007 max_tinst_depth, d);
5009 print_instantiation_context ();
5014 new = make_node (TINST_LEVEL);
5015 TINST_DECL (new) = d;
5016 TINST_LOCATION (new) = input_location;
5017 TINST_IN_SYSTEM_HEADER_P (new) = in_system_header;
5018 TREE_CHAIN (new) = current_tinst_level;
5019 current_tinst_level = new;
5022 #ifdef GATHER_STATISTICS
5023 if (tinst_depth > depth_reached)
5024 depth_reached = tinst_depth;
5031 /* We're done instantiating this template; return to the instantiation
5035 pop_tinst_level (void)
5037 tree old = current_tinst_level;
5039 /* Restore the filename and line number stashed away when we started
5040 this instantiation. */
5041 input_location = TINST_LOCATION (old);
5042 in_system_header = TINST_IN_SYSTEM_HEADER_P (old);
5043 current_tinst_level = TREE_CHAIN (old);
5048 /* We're instantiating a deferred template; restore the template
5049 instantiation context in which the instantiation was requested, which
5050 is one step out from LEVEL. */
5053 reopen_tinst_level (tree level)
5058 for (t = level; t; t = TREE_CHAIN (t))
5061 current_tinst_level = level;
5065 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5066 vector of template arguments, as for tsubst.
5068 Returns an appropriate tsubst'd friend declaration. */
5071 tsubst_friend_function (tree decl, tree args)
5075 if (TREE_CODE (decl) == FUNCTION_DECL
5076 && DECL_TEMPLATE_INSTANTIATION (decl)
5077 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5078 /* This was a friend declared with an explicit template
5079 argument list, e.g.:
5083 to indicate that f was a template instantiation, not a new
5084 function declaration. Now, we have to figure out what
5085 instantiation of what template. */
5087 tree template_id, arglist, fns;
5090 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5092 /* Friend functions are looked up in the containing namespace scope.
5093 We must enter that scope, to avoid finding member functions of the
5094 current cless with same name. */
5095 push_nested_namespace (ns);
5096 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5097 tf_error | tf_warning, NULL_TREE);
5098 pop_nested_namespace (ns);
5099 arglist = tsubst (DECL_TI_ARGS (decl), args,
5100 tf_error | tf_warning, NULL_TREE);
5101 template_id = lookup_template_function (fns, arglist);
5103 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5104 tmpl = determine_specialization (template_id, new_friend,
5106 /*need_member_template=*/0,
5107 TREE_VEC_LENGTH (args));
5108 return instantiate_template (tmpl, new_args, tf_error);
5111 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5113 /* The NEW_FRIEND will look like an instantiation, to the
5114 compiler, but is not an instantiation from the point of view of
5115 the language. For example, we might have had:
5117 template <class T> struct S {
5118 template <class U> friend void f(T, U);
5121 Then, in S<int>, template <class U> void f(int, U) is not an
5122 instantiation of anything. */
5123 if (new_friend == error_mark_node)
5124 return error_mark_node;
5126 DECL_USE_TEMPLATE (new_friend) = 0;
5127 if (TREE_CODE (decl) == TEMPLATE_DECL)
5129 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5130 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5131 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5134 /* The mangled name for the NEW_FRIEND is incorrect. The function
5135 is not a template instantiation and should not be mangled like
5136 one. Therefore, we forget the mangling here; we'll recompute it
5137 later if we need it. */
5138 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5140 SET_DECL_RTL (new_friend, NULL_RTX);
5141 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5144 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5147 tree new_friend_template_info;
5148 tree new_friend_result_template_info;
5150 int new_friend_is_defn;
5152 /* We must save some information from NEW_FRIEND before calling
5153 duplicate decls since that function will free NEW_FRIEND if
5155 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5156 new_friend_is_defn =
5157 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5158 (template_for_substitution (new_friend)))
5160 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5162 /* This declaration is a `primary' template. */
5163 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5165 new_friend_result_template_info
5166 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5169 new_friend_result_template_info = NULL_TREE;
5171 /* Inside pushdecl_namespace_level, we will push into the
5172 current namespace. However, the friend function should go
5173 into the namespace of the template. */
5174 ns = decl_namespace_context (new_friend);
5175 push_nested_namespace (ns);
5176 old_decl = pushdecl_namespace_level (new_friend);
5177 pop_nested_namespace (ns);
5179 if (old_decl != new_friend)
5181 /* This new friend declaration matched an existing
5182 declaration. For example, given:
5184 template <class T> void f(T);
5185 template <class U> class C {
5186 template <class T> friend void f(T) {}
5189 the friend declaration actually provides the definition
5190 of `f', once C has been instantiated for some type. So,
5191 old_decl will be the out-of-class template declaration,
5192 while new_friend is the in-class definition.
5194 But, if `f' was called before this point, the
5195 instantiation of `f' will have DECL_TI_ARGS corresponding
5196 to `T' but not to `U', references to which might appear
5197 in the definition of `f'. Previously, the most general
5198 template for an instantiation of `f' was the out-of-class
5199 version; now it is the in-class version. Therefore, we
5200 run through all specialization of `f', adding to their
5201 DECL_TI_ARGS appropriately. In particular, they need a
5202 new set of outer arguments, corresponding to the
5203 arguments for this class instantiation.
5205 The same situation can arise with something like this:
5208 template <class T> class C {
5212 when `C<int>' is instantiated. Now, `f(int)' is defined
5215 if (!new_friend_is_defn)
5216 /* On the other hand, if the in-class declaration does
5217 *not* provide a definition, then we don't want to alter
5218 existing definitions. We can just leave everything
5223 /* Overwrite whatever template info was there before, if
5224 any, with the new template information pertaining to
5226 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5228 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5229 reregister_specialization (new_friend,
5230 most_general_template (old_decl),
5235 tree new_friend_args;
5237 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5238 = new_friend_result_template_info;
5240 new_friend_args = TI_ARGS (new_friend_template_info);
5241 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5245 tree spec = TREE_VALUE (t);
5248 = add_outermost_template_args (new_friend_args,
5249 DECL_TI_ARGS (spec));
5252 /* Now, since specializations are always supposed to
5253 hang off of the most general template, we must move
5255 t = most_general_template (old_decl);
5258 DECL_TEMPLATE_SPECIALIZATIONS (t)
5259 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5260 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5261 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5266 /* The information from NEW_FRIEND has been merged into OLD_DECL
5267 by duplicate_decls. */
5268 new_friend = old_decl;
5273 tree context = DECL_CONTEXT (new_friend);
5277 template <class T> class C {
5278 template <class U> friend void C1<U>::f (); // case 1
5279 friend void C2<T>::f (); // case 2
5281 we only need to make sure CONTEXT is a complete type for
5282 case 2. To distinguish between the two cases, we note that
5283 CONTEXT of case 1 remains dependent type after tsubst while
5284 this isn't true for case 2. */
5285 ++processing_template_decl;
5286 dependent_p = dependent_type_p (context);
5287 --processing_template_decl;
5290 && !complete_type_or_else (context, NULL_TREE))
5291 return error_mark_node;
5293 if (COMPLETE_TYPE_P (context))
5295 /* Check to see that the declaration is really present, and,
5296 possibly obtain an improved declaration. */
5297 tree fn = check_classfn (context,
5298 new_friend, NULL_TREE);
5308 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5309 template arguments, as for tsubst.
5311 Returns an appropriate tsubst'd friend type or error_mark_node on
5315 tsubst_friend_class (tree friend_tmpl, tree args)
5321 context = DECL_CONTEXT (friend_tmpl);
5325 if (TREE_CODE (context) == NAMESPACE_DECL)
5326 push_nested_namespace (context);
5328 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5331 /* First, we look for a class template. */
5332 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5334 /* But, if we don't find one, it might be because we're in a
5335 situation like this:
5343 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5344 for `S<int>', not the TEMPLATE_DECL. */
5345 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5347 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5348 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5351 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5353 /* The friend template has already been declared. Just
5354 check to see that the declarations match, and install any new
5355 default parameters. We must tsubst the default parameters,
5356 of course. We only need the innermost template parameters
5357 because that is all that redeclare_class_template will look
5359 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5360 > TMPL_ARGS_DEPTH (args))
5363 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5364 args, tf_error | tf_warning);
5365 redeclare_class_template (TREE_TYPE (tmpl), parms);
5368 friend_type = TREE_TYPE (tmpl);
5372 /* The friend template has not already been declared. In this
5373 case, the instantiation of the template class will cause the
5374 injection of this template into the global scope. */
5375 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5377 /* The new TMPL is not an instantiation of anything, so we
5378 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5379 the new type because that is supposed to be the corresponding
5380 template decl, i.e., TMPL. */
5381 DECL_USE_TEMPLATE (tmpl) = 0;
5382 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5383 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5384 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5385 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5387 /* Inject this template into the global scope. */
5388 friend_type = TREE_TYPE (pushdecl_top_level (tmpl));
5393 if (TREE_CODE (context) == NAMESPACE_DECL)
5394 pop_nested_namespace (context);
5396 pop_nested_class ();
5402 /* Returns zero if TYPE cannot be completed later due to circularity.
5403 Otherwise returns one. */
5406 can_complete_type_without_circularity (tree type)
5408 if (type == NULL_TREE || type == error_mark_node)
5410 else if (COMPLETE_TYPE_P (type))
5412 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5413 return can_complete_type_without_circularity (TREE_TYPE (type));
5414 else if (CLASS_TYPE_P (type)
5415 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5422 instantiate_class_template (tree type)
5424 tree template, args, pattern, t, member;
5429 if (type == error_mark_node)
5430 return error_mark_node;
5432 if (TYPE_BEING_DEFINED (type)
5433 || COMPLETE_TYPE_P (type)
5434 || dependent_type_p (type))
5437 /* Figure out which template is being instantiated. */
5438 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5439 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5441 /* Figure out which arguments are being used to do the
5443 args = CLASSTYPE_TI_ARGS (type);
5445 /* Determine what specialization of the original template to
5447 t = most_specialized_class (template, args);
5448 if (t == error_mark_node)
5450 const char *str = "candidates are:";
5451 error ("ambiguous class template instantiation for %q#T", type);
5452 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5455 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5457 error ("%s %+#T", str, TREE_TYPE (t));
5461 TYPE_BEING_DEFINED (type) = 1;
5462 return error_mark_node;
5466 pattern = TREE_TYPE (t);
5468 pattern = TREE_TYPE (template);
5470 /* If the template we're instantiating is incomplete, then clearly
5471 there's nothing we can do. */
5472 if (!COMPLETE_TYPE_P (pattern))
5475 /* If we've recursively instantiated too many templates, stop. */
5476 if (! push_tinst_level (type))
5479 /* Now we're really doing the instantiation. Mark the type as in
5480 the process of being defined. */
5481 TYPE_BEING_DEFINED (type) = 1;
5483 /* We may be in the middle of deferred access check. Disable
5485 push_deferring_access_checks (dk_no_deferred);
5487 push_to_top_level ();
5491 /* This TYPE is actually an instantiation of a partial
5492 specialization. We replace the innermost set of ARGS with
5493 the arguments appropriate for substitution. For example,
5496 template <class T> struct S {};
5497 template <class T> struct S<T*> {};
5499 and supposing that we are instantiating S<int*>, ARGS will
5500 present be {int*} but we need {int}. */
5502 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5505 /* If there were multiple levels in ARGS, replacing the
5506 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5507 want, so we make a copy first. */
5508 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5510 args = copy_node (args);
5511 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5517 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5519 /* Set the input location to the template definition. This is needed
5520 if tsubsting causes an error. */
5521 typedecl = TYPE_MAIN_DECL (type);
5522 input_location = DECL_SOURCE_LOCATION (typedecl);
5523 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
5525 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5526 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5527 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5528 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5529 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5530 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5531 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5532 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5533 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5534 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5535 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5536 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5537 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5538 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5539 if (ANON_AGGR_TYPE_P (pattern))
5540 SET_ANON_AGGR_TYPE_P (type);
5541 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
5543 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
5544 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
5547 pbinfo = TYPE_BINFO (pattern);
5549 /* We should never instantiate a nested class before its enclosing
5550 class; we need to look up the nested class by name before we can
5551 instantiate it, and that lookup should instantiate the enclosing
5553 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5554 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5555 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5557 base_list = NULL_TREE;
5558 if (BINFO_N_BASE_BINFOS (pbinfo))
5561 tree context = TYPE_CONTEXT (type);
5565 /* We must enter the scope containing the type, as that is where
5566 the accessibility of types named in dependent bases are
5568 pushed_scope = push_scope (context ? context : global_namespace);
5570 /* Substitute into each of the bases to determine the actual
5572 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5575 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5577 /* Substitute to figure out the base class. */
5578 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5579 if (base == error_mark_node)
5582 base_list = tree_cons (access, base, base_list);
5583 if (BINFO_VIRTUAL_P (pbase_binfo))
5584 TREE_TYPE (base_list) = integer_type_node;
5587 /* The list is now in reverse order; correct that. */
5588 base_list = nreverse (base_list);
5591 pop_scope (pushed_scope);
5593 /* Now call xref_basetypes to set up all the base-class
5595 xref_basetypes (type, base_list);
5598 /* Now that our base classes are set up, enter the scope of the
5599 class, so that name lookups into base classes, etc. will work
5600 correctly. This is precisely analogous to what we do in
5601 begin_class_definition when defining an ordinary non-template
5605 /* Now members are processed in the order of declaration. */
5606 for (member = CLASSTYPE_DECL_LIST (pattern);
5607 member; member = TREE_CHAIN (member))
5609 tree t = TREE_VALUE (member);
5611 if (TREE_PURPOSE (member))
5615 /* Build new CLASSTYPE_NESTED_UTDS. */
5618 tree name = TYPE_IDENTIFIER (tag);
5620 bool class_template_p;
5622 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5623 && TYPE_LANG_SPECIFIC (tag)
5624 && CLASSTYPE_IS_TEMPLATE (tag));
5625 /* If the member is a class template, then -- even after
5626 substitution -- there may be dependent types in the
5627 template argument list for the class. We increment
5628 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5629 that function will assume that no types are dependent
5630 when outside of a template. */
5631 if (class_template_p)
5632 ++processing_template_decl;
5633 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5634 if (class_template_p)
5635 --processing_template_decl;
5636 if (newtag == error_mark_node)
5639 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5641 if (class_template_p)
5642 /* Unfortunately, lookup_template_class sets
5643 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5644 instantiation (i.e., for the type of a member
5645 template class nested within a template class.)
5646 This behavior is required for
5647 maybe_process_partial_specialization to work
5648 correctly, but is not accurate in this case;
5649 the TAG is not an instantiation of anything.
5650 (The corresponding TEMPLATE_DECL is an
5651 instantiation, but the TYPE is not.) */
5652 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5654 /* Now, we call pushtag to put this NEWTAG into the scope of
5655 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5656 pushtag calling push_template_decl. We don't have to do
5657 this for enums because it will already have been done in
5660 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5661 pushtag (name, newtag, /*tag_scope=*/ts_current);
5664 else if (TREE_CODE (t) == FUNCTION_DECL
5665 || DECL_FUNCTION_TEMPLATE_P (t))
5667 /* Build new TYPE_METHODS. */
5670 if (TREE_CODE (t) == TEMPLATE_DECL)
5671 ++processing_template_decl;
5672 r = tsubst (t, args, tf_error, NULL_TREE);
5673 if (TREE_CODE (t) == TEMPLATE_DECL)
5674 --processing_template_decl;
5675 set_current_access_from_decl (r);
5676 grok_special_member_properties (r);
5677 finish_member_declaration (r);
5681 /* Build new TYPE_FIELDS. */
5683 if (TREE_CODE (t) != CONST_DECL)
5687 /* The the file and line for this declaration, to
5688 assist in error message reporting. Since we
5689 called push_tinst_level above, we don't need to
5691 input_location = DECL_SOURCE_LOCATION (t);
5693 if (TREE_CODE (t) == TEMPLATE_DECL)
5694 ++processing_template_decl;
5695 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5696 if (TREE_CODE (t) == TEMPLATE_DECL)
5697 --processing_template_decl;
5698 if (TREE_CODE (r) == VAR_DECL)
5702 if (DECL_INITIALIZED_IN_CLASS_P (r))
5703 init = tsubst_expr (DECL_INITIAL (t), args,
5704 tf_error | tf_warning, NULL_TREE);
5708 finish_static_data_member_decl
5709 (r, init, /*asmspec_tree=*/NULL_TREE, /*flags=*/0);
5711 if (DECL_INITIALIZED_IN_CLASS_P (r))
5712 check_static_variable_definition (r, TREE_TYPE (r));
5714 else if (TREE_CODE (r) == FIELD_DECL)
5716 /* Determine whether R has a valid type and can be
5717 completed later. If R is invalid, then it is
5718 replaced by error_mark_node so that it will not be
5719 added to TYPE_FIELDS. */
5720 tree rtype = TREE_TYPE (r);
5721 if (can_complete_type_without_circularity (rtype))
5722 complete_type (rtype);
5724 if (!COMPLETE_TYPE_P (rtype))
5726 cxx_incomplete_type_error (r, rtype);
5727 r = error_mark_node;
5731 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5732 such a thing will already have been added to the field
5733 list by tsubst_enum in finish_member_declaration in the
5734 CLASSTYPE_NESTED_UTDS case above. */
5735 if (!(TREE_CODE (r) == TYPE_DECL
5736 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5737 && DECL_ARTIFICIAL (r)))
5739 set_current_access_from_decl (r);
5740 finish_member_declaration (r);
5747 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5749 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5751 tree friend_type = t;
5752 bool adjust_processing_template_decl = false;
5754 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5756 /* template <class T> friend class C; */
5757 friend_type = tsubst_friend_class (friend_type, args);
5758 adjust_processing_template_decl = true;
5760 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5762 /* template <class T> friend class C::D; */
5763 friend_type = tsubst (friend_type, args,
5764 tf_error | tf_warning, NULL_TREE);
5765 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5766 friend_type = TREE_TYPE (friend_type);
5767 adjust_processing_template_decl = true;
5769 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5771 /* This could be either
5775 when dependent_type_p is false or
5777 template <class U> friend class T::C;
5780 friend_type = tsubst (friend_type, args,
5781 tf_error | tf_warning, NULL_TREE);
5782 /* Bump processing_template_decl for correct
5783 dependent_type_p calculation. */
5784 ++processing_template_decl;
5785 if (dependent_type_p (friend_type))
5786 adjust_processing_template_decl = true;
5787 --processing_template_decl;
5789 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
5790 && hidden_name_p (TYPE_NAME (friend_type)))
5794 where C hasn't been declared yet. Let's lookup name
5795 from namespace scope directly, bypassing any name that
5796 come from dependent base class. */
5797 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5799 /* The call to xref_tag_from_type does injection for friend
5801 push_nested_namespace (ns);
5803 xref_tag_from_type (friend_type, NULL_TREE,
5804 /*tag_scope=*/ts_current);
5805 pop_nested_namespace (ns);
5807 else if (uses_template_parms (friend_type))
5808 /* friend class C<T>; */
5809 friend_type = tsubst (friend_type, args,
5810 tf_error | tf_warning, NULL_TREE);
5815 where C is already declared or
5817 friend class C<int>;
5819 We don't have to do anything in these cases. */
5821 if (adjust_processing_template_decl)
5822 /* Trick make_friend_class into realizing that the friend
5823 we're adding is a template, not an ordinary class. It's
5824 important that we use make_friend_class since it will
5825 perform some error-checking and output cross-reference
5827 ++processing_template_decl;
5829 if (friend_type != error_mark_node)
5830 make_friend_class (type, friend_type, /*complain=*/false);
5832 if (adjust_processing_template_decl)
5833 --processing_template_decl;
5837 /* Build new DECL_FRIENDLIST. */
5840 /* The the file and line for this declaration, to
5841 assist in error message reporting. Since we
5842 called push_tinst_level above, we don't need to
5844 input_location = DECL_SOURCE_LOCATION (t);
5846 if (TREE_CODE (t) == TEMPLATE_DECL)
5848 ++processing_template_decl;
5849 push_deferring_access_checks (dk_no_check);
5852 r = tsubst_friend_function (t, args);
5853 add_friend (type, r, /*complain=*/false);
5854 if (TREE_CODE (t) == TEMPLATE_DECL)
5856 pop_deferring_access_checks ();
5857 --processing_template_decl;
5863 /* Set the file and line number information to whatever is given for
5864 the class itself. This puts error messages involving generated
5865 implicit functions at a predictable point, and the same point
5866 that would be used for non-template classes. */
5867 input_location = DECL_SOURCE_LOCATION (typedecl);
5869 unreverse_member_declarations (type);
5870 finish_struct_1 (type);
5871 TYPE_BEING_DEFINED (type) = 0;
5873 /* Now that the class is complete, instantiate default arguments for
5874 any member functions. We don't do this earlier because the
5875 default arguments may reference members of the class. */
5876 if (!PRIMARY_TEMPLATE_P (template))
5877 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5878 if (TREE_CODE (t) == FUNCTION_DECL
5879 /* Implicitly generated member functions will not have template
5880 information; they are not instantiations, but instead are
5881 created "fresh" for each instantiation. */
5882 && DECL_TEMPLATE_INFO (t))
5883 tsubst_default_arguments (t);
5886 pop_from_top_level ();
5887 pop_deferring_access_checks ();
5890 /* The vtable for a template class can be emitted in any translation
5891 unit in which the class is instantiated. When there is no key
5892 method, however, finish_struct_1 will already have added TYPE to
5893 the keyed_classes list. */
5894 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5895 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5901 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5907 else if (TYPE_P (t))
5908 r = tsubst (t, args, complain, in_decl);
5911 r = tsubst_expr (t, args, complain, in_decl);
5913 if (!uses_template_parms (r))
5915 /* Sometimes, one of the args was an expression involving a
5916 template constant parameter, like N - 1. Now that we've
5917 tsubst'd, we might have something like 2 - 1. This will
5918 confuse lookup_template_class, so we do constant folding
5919 here. We have to unset processing_template_decl, to fool
5920 tsubst_copy_and_build() into building an actual tree. */
5922 /* If the TREE_TYPE of ARG is not NULL_TREE, ARG is already
5923 as simple as it's going to get, and trying to reprocess
5924 the trees will break. Once tsubst_expr et al DTRT for
5925 non-dependent exprs, this code can go away, as the type
5926 will always be set. */
5929 int saved_processing_template_decl = processing_template_decl;
5930 processing_template_decl = 0;
5931 r = tsubst_copy_and_build (r, /*args=*/NULL_TREE,
5932 tf_error, /*in_decl=*/NULL_TREE,
5933 /*function_p=*/false);
5934 processing_template_decl = saved_processing_template_decl;
5942 /* Substitute ARGS into the vector or list of template arguments T. */
5945 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5947 int len = TREE_VEC_LENGTH (t);
5948 int need_new = 0, i;
5949 tree *elts = alloca (len * sizeof (tree));
5951 for (i = 0; i < len; i++)
5953 tree orig_arg = TREE_VEC_ELT (t, i);
5956 if (TREE_CODE (orig_arg) == TREE_VEC)
5957 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5959 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5961 if (new_arg == error_mark_node)
5962 return error_mark_node;
5965 if (new_arg != orig_arg)
5972 t = make_tree_vec (len);
5973 for (i = 0; i < len; i++)
5974 TREE_VEC_ELT (t, i) = elts[i];
5979 /* Return the result of substituting ARGS into the template parameters
5980 given by PARMS. If there are m levels of ARGS and m + n levels of
5981 PARMS, then the result will contain n levels of PARMS. For
5982 example, if PARMS is `template <class T> template <class U>
5983 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5984 result will be `template <int*, double, class V>'. */
5987 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
5992 for (new_parms = &r;
5993 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
5994 new_parms = &(TREE_CHAIN (*new_parms)),
5995 parms = TREE_CHAIN (parms))
5998 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
6001 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
6003 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
6004 tree default_value = TREE_PURPOSE (tuple);
6005 tree parm_decl = TREE_VALUE (tuple);
6007 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
6008 if (TREE_CODE (parm_decl) == PARM_DECL
6009 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
6010 parm_decl = error_mark_node;
6011 default_value = tsubst_template_arg (default_value, args,
6012 complain, NULL_TREE);
6014 tuple = build_tree_list (default_value, parm_decl);
6015 TREE_VEC_ELT (new_vec, i) = tuple;
6019 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6020 - TMPL_ARGS_DEPTH (args)),
6021 new_vec, NULL_TREE);
6027 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6028 type T. If T is not an aggregate or enumeration type, it is
6029 handled as if by tsubst. IN_DECL is as for tsubst. If
6030 ENTERING_SCOPE is nonzero, T is the context for a template which
6031 we are presently tsubst'ing. Return the substituted value. */
6034 tsubst_aggr_type (tree t,
6036 tsubst_flags_t complain,
6043 switch (TREE_CODE (t))
6046 if (TYPE_PTRMEMFUNC_P (t))
6047 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6049 /* Else fall through. */
6052 if (TYPE_TEMPLATE_INFO (t))
6058 /* First, determine the context for the type we are looking
6060 context = TYPE_CONTEXT (t);
6062 context = tsubst_aggr_type (context, args, complain,
6063 in_decl, /*entering_scope=*/1);
6065 /* Then, figure out what arguments are appropriate for the
6066 type we are trying to find. For example, given:
6068 template <class T> struct S;
6069 template <class T, class U> void f(T, U) { S<U> su; }
6071 and supposing that we are instantiating f<int, double>,
6072 then our ARGS will be {int, double}, but, when looking up
6073 S we only want {double}. */
6074 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6076 if (argvec == error_mark_node)
6077 return error_mark_node;
6079 r = lookup_template_class (t, argvec, in_decl, context,
6080 entering_scope, complain);
6082 return cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6085 /* This is not a template type, so there's nothing to do. */
6089 return tsubst (t, args, complain, in_decl);
6093 /* Substitute into the default argument ARG (a default argument for
6094 FN), which has the indicated TYPE. */
6097 tsubst_default_argument (tree fn, tree type, tree arg)
6099 tree saved_class_ptr = NULL_TREE;
6100 tree saved_class_ref = NULL_TREE;
6102 /* This default argument came from a template. Instantiate the
6103 default argument here, not in tsubst. In the case of
6112 we must be careful to do name lookup in the scope of S<T>,
6113 rather than in the current class. */
6114 push_access_scope (fn);
6115 /* The default argument expression should not be considered to be
6116 within the scope of FN. Since push_access_scope sets
6117 current_function_decl, we must explicitly clear it here. */
6118 current_function_decl = NULL_TREE;
6119 /* The "this" pointer is not valid in a default argument. */
6122 saved_class_ptr = current_class_ptr;
6123 cp_function_chain->x_current_class_ptr = NULL_TREE;
6124 saved_class_ref = current_class_ref;
6125 cp_function_chain->x_current_class_ref = NULL_TREE;
6128 push_deferring_access_checks(dk_no_deferred);
6129 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6130 tf_error | tf_warning, NULL_TREE);
6131 pop_deferring_access_checks();
6133 /* Restore the "this" pointer. */
6136 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6137 cp_function_chain->x_current_class_ref = saved_class_ref;
6140 pop_access_scope (fn);
6142 /* Make sure the default argument is reasonable. */
6143 arg = check_default_argument (type, arg);
6148 /* Substitute into all the default arguments for FN. */
6151 tsubst_default_arguments (tree fn)
6156 tmpl_args = DECL_TI_ARGS (fn);
6158 /* If this function is not yet instantiated, we certainly don't need
6159 its default arguments. */
6160 if (uses_template_parms (tmpl_args))
6163 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6165 arg = TREE_CHAIN (arg))
6166 if (TREE_PURPOSE (arg))
6167 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6169 TREE_PURPOSE (arg));
6172 /* Substitute the ARGS into the T, which is a _DECL. Return the
6173 result of the substitution. Issue error and warning messages under
6174 control of COMPLAIN. */
6177 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6179 location_t saved_loc;
6183 /* Set the filename and linenumber to improve error-reporting. */
6184 saved_loc = input_location;
6185 input_location = DECL_SOURCE_LOCATION (t);
6187 switch (TREE_CODE (t))
6191 /* We can get here when processing a member function template,
6192 member class template, and template template parameter of
6193 a template class. */
6194 tree decl = DECL_TEMPLATE_RESULT (t);
6199 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6201 /* Template template parameter is treated here. */
6202 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6203 if (new_type == error_mark_node)
6204 return error_mark_node;
6207 TREE_CHAIN (r) = NULL_TREE;
6208 TREE_TYPE (r) = new_type;
6209 DECL_TEMPLATE_RESULT (r)
6210 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6211 DECL_TEMPLATE_PARMS (r)
6212 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6214 TYPE_NAME (new_type) = r;
6218 /* We might already have an instance of this template.
6219 The ARGS are for the surrounding class type, so the
6220 full args contain the tsubst'd args for the context,
6221 plus the innermost args from the template decl. */
6222 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6223 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6224 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6225 full_args = tsubst_template_args (tmpl_args, args,
6228 /* tsubst_template_args doesn't copy the vector if
6229 nothing changed. But, *something* should have
6231 gcc_assert (full_args != tmpl_args);
6233 spec = retrieve_specialization (t, full_args,
6234 /*class_specializations_p=*/true);
6235 if (spec != NULL_TREE)
6241 /* Make a new template decl. It will be similar to the
6242 original, but will record the current template arguments.
6243 We also create a new function declaration, which is just
6244 like the old one, but points to this new template, rather
6245 than the old one. */
6247 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6248 TREE_CHAIN (r) = NULL_TREE;
6251 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6253 /*entering_scope=*/1);
6254 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6256 if (TREE_CODE (decl) == TYPE_DECL)
6258 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6259 if (new_type == error_mark_node)
6260 return error_mark_node;
6262 TREE_TYPE (r) = new_type;
6263 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6264 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6265 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6269 tree new_decl = tsubst (decl, args, complain, in_decl);
6270 if (new_decl == error_mark_node)
6271 return error_mark_node;
6273 DECL_TEMPLATE_RESULT (r) = new_decl;
6274 DECL_TI_TEMPLATE (new_decl) = r;
6275 TREE_TYPE (r) = TREE_TYPE (new_decl);
6276 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6279 SET_DECL_IMPLICIT_INSTANTIATION (r);
6280 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6281 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6283 /* The template parameters for this new template are all the
6284 template parameters for the old template, except the
6285 outermost level of parameters. */
6286 DECL_TEMPLATE_PARMS (r)
6287 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6290 if (PRIMARY_TEMPLATE_P (t))
6291 DECL_PRIMARY_TEMPLATE (r) = r;
6293 if (TREE_CODE (decl) != TYPE_DECL)
6294 /* Record this non-type partial instantiation. */
6295 register_specialization (r, t,
6296 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)));
6303 tree argvec = NULL_TREE;
6311 /* Nobody should be tsubst'ing into non-template functions. */
6312 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6314 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6319 /* If T is not dependent, just return it. We have to
6320 increment PROCESSING_TEMPLATE_DECL because
6321 value_dependent_expression_p assumes that nothing is
6322 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6323 ++processing_template_decl;
6324 dependent_p = value_dependent_expression_p (t);
6325 --processing_template_decl;
6329 /* Calculate the most general template of which R is a
6330 specialization, and the complete set of arguments used to
6332 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6333 argvec = tsubst_template_args (DECL_TI_ARGS
6334 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6335 args, complain, in_decl);
6337 /* Check to see if we already have this specialization. */
6338 spec = retrieve_specialization (gen_tmpl, argvec,
6339 /*class_specializations_p=*/false);
6347 /* We can see more levels of arguments than parameters if
6348 there was a specialization of a member template, like
6351 template <class T> struct S { template <class U> void f(); }
6352 template <> template <class U> void S<int>::f(U);
6354 Here, we'll be substituting into the specialization,
6355 because that's where we can find the code we actually
6356 want to generate, but we'll have enough arguments for
6357 the most general template.
6359 We also deal with the peculiar case:
6361 template <class T> struct S {
6362 template <class U> friend void f();
6364 template <class U> void f() {}
6366 template void f<double>();
6368 Here, the ARGS for the instantiation of will be {int,
6369 double}. But, we only need as many ARGS as there are
6370 levels of template parameters in CODE_PATTERN. We are
6371 careful not to get fooled into reducing the ARGS in
6374 template <class T> struct S { template <class U> void f(U); }
6375 template <class T> template <> void S<T>::f(int) {}
6377 which we can spot because the pattern will be a
6378 specialization in this case. */
6379 args_depth = TMPL_ARGS_DEPTH (args);
6381 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6382 if (args_depth > parms_depth
6383 && !DECL_TEMPLATE_SPECIALIZATION (t))
6384 args = get_innermost_template_args (args, parms_depth);
6388 /* This special case arises when we have something like this:
6390 template <class T> struct S {
6391 friend void f<int>(int, double);
6394 Here, the DECL_TI_TEMPLATE for the friend declaration
6395 will be an IDENTIFIER_NODE. We are being called from
6396 tsubst_friend_function, and we want only to create a
6397 new decl (R) with appropriate types so that we can call
6398 determine_specialization. */
6399 gen_tmpl = NULL_TREE;
6402 if (DECL_CLASS_SCOPE_P (t))
6404 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6408 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6409 complain, t, /*entering_scope=*/1);
6414 ctx = DECL_CONTEXT (t);
6416 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6417 if (type == error_mark_node)
6418 return error_mark_node;
6420 /* We do NOT check for matching decls pushed separately at this
6421 point, as they may not represent instantiations of this
6422 template, and in any case are considered separate under the
6425 DECL_USE_TEMPLATE (r) = 0;
6426 TREE_TYPE (r) = type;
6427 /* Clear out the mangled name and RTL for the instantiation. */
6428 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6429 SET_DECL_RTL (r, NULL_RTX);
6430 DECL_INITIAL (r) = NULL_TREE;
6431 DECL_CONTEXT (r) = ctx;
6433 if (member && DECL_CONV_FN_P (r))
6434 /* Type-conversion operator. Reconstruct the name, in
6435 case it's the name of one of the template's parameters. */
6436 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6438 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6440 DECL_RESULT (r) = NULL_TREE;
6442 TREE_STATIC (r) = 0;
6443 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6444 DECL_EXTERNAL (r) = 1;
6445 /* If this is an instantiation of a function with internal
6446 linkage, we already know what object file linkage will be
6447 assigned to the instantiation. */
6448 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6449 DECL_DEFER_OUTPUT (r) = 0;
6450 TREE_CHAIN (r) = NULL_TREE;
6451 DECL_PENDING_INLINE_INFO (r) = 0;
6452 DECL_PENDING_INLINE_P (r) = 0;
6453 DECL_SAVED_TREE (r) = NULL_TREE;
6455 if (DECL_CLONED_FUNCTION (r))
6457 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6459 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6460 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6463 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6464 this in the special friend case mentioned above where
6465 GEN_TMPL is NULL. */
6468 DECL_TEMPLATE_INFO (r)
6469 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6470 SET_DECL_IMPLICIT_INSTANTIATION (r);
6471 register_specialization (r, gen_tmpl, argvec);
6473 /* We're not supposed to instantiate default arguments
6474 until they are called, for a template. But, for a
6477 template <class T> void f ()
6478 { extern void g(int i = T()); }
6480 we should do the substitution when the template is
6481 instantiated. We handle the member function case in
6482 instantiate_class_template since the default arguments
6483 might refer to other members of the class. */
6485 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6486 && !uses_template_parms (argvec))
6487 tsubst_default_arguments (r);
6490 /* Copy the list of befriending classes. */
6491 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6493 friends = &TREE_CHAIN (*friends))
6495 *friends = copy_node (*friends);
6496 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6501 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6503 maybe_retrofit_in_chrg (r);
6504 if (DECL_CONSTRUCTOR_P (r))
6505 grok_ctor_properties (ctx, r);
6506 /* If this is an instantiation of a member template, clone it.
6507 If it isn't, that'll be handled by
6508 clone_constructors_and_destructors. */
6509 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6510 clone_function_decl (r, /*update_method_vec_p=*/0);
6512 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6513 grok_op_properties (r, (complain & tf_error) != 0);
6515 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6516 SET_DECL_FRIEND_CONTEXT (r,
6517 tsubst (DECL_FRIEND_CONTEXT (t),
6518 args, complain, in_decl));
6527 if (DECL_TEMPLATE_PARM_P (t))
6528 SET_DECL_TEMPLATE_PARM_P (r);
6530 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6531 type = type_decays_to (type);
6532 TREE_TYPE (r) = type;
6533 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6535 if (DECL_INITIAL (r))
6537 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6538 DECL_INITIAL (r) = TREE_TYPE (r);
6540 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6544 DECL_CONTEXT (r) = NULL_TREE;
6546 if (!DECL_TEMPLATE_PARM_P (r))
6547 DECL_ARG_TYPE (r) = type_passed_as (type);
6549 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6550 complain, TREE_CHAIN (t));
6559 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6560 if (type == error_mark_node)
6561 return error_mark_node;
6562 TREE_TYPE (r) = type;
6563 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6565 /* We don't have to set DECL_CONTEXT here; it is set by
6566 finish_member_declaration. */
6567 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6569 TREE_CHAIN (r) = NULL_TREE;
6570 if (VOID_TYPE_P (type))
6571 error ("instantiation of %q+D as type %qT", r, type);
6576 /* We reach here only for member using decls. */
6577 if (DECL_DEPENDENT_P (t))
6579 r = do_class_using_decl
6580 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
6581 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
6583 r = error_mark_node;
6588 TREE_CHAIN (r) = NULL_TREE;
6595 tree argvec = NULL_TREE;
6596 tree gen_tmpl = NULL_TREE;
6598 tree tmpl = NULL_TREE;
6600 tree type = NULL_TREE;
6603 if (TREE_CODE (t) == TYPE_DECL)
6605 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6606 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6607 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6609 /* If this is the canonical decl, we don't have to
6610 mess with instantiations, and often we can't (for
6611 typename, template type parms and such). Note that
6612 TYPE_NAME is not correct for the above test if
6613 we've copied the type for a typedef. */
6614 r = TYPE_NAME (type);
6619 /* Assume this is a non-local variable. */
6622 if (TYPE_P (CP_DECL_CONTEXT (t)))
6623 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6625 in_decl, /*entering_scope=*/1);
6626 else if (DECL_NAMESPACE_SCOPE_P (t))
6627 ctx = DECL_CONTEXT (t);
6630 /* Subsequent calls to pushdecl will fill this in. */
6635 /* Check to see if we already have this specialization. */
6638 tmpl = DECL_TI_TEMPLATE (t);
6639 gen_tmpl = most_general_template (tmpl);
6640 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6641 spec = retrieve_specialization (gen_tmpl, argvec,
6642 /*class_specializations_p=*/false);
6645 spec = retrieve_local_specialization (t);
6654 if (TREE_CODE (r) == VAR_DECL)
6656 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6657 if (type == error_mark_node)
6658 return error_mark_node;
6659 type = complete_type (type);
6660 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6661 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6662 type = check_var_type (DECL_NAME (r), type);
6664 else if (DECL_SELF_REFERENCE_P (t))
6665 SET_DECL_SELF_REFERENCE_P (r);
6666 TREE_TYPE (r) = type;
6667 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6668 DECL_CONTEXT (r) = ctx;
6669 /* Clear out the mangled name and RTL for the instantiation. */
6670 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6671 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6672 SET_DECL_RTL (r, NULL_RTX);
6674 /* Don't try to expand the initializer until someone tries to use
6675 this variable; otherwise we run into circular dependencies. */
6676 DECL_INITIAL (r) = NULL_TREE;
6677 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6678 SET_DECL_RTL (r, NULL_RTX);
6679 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6681 /* Even if the original location is out of scope, the newly
6682 substituted one is not. */
6683 if (TREE_CODE (r) == VAR_DECL)
6685 DECL_DEAD_FOR_LOCAL (r) = 0;
6686 DECL_INITIALIZED_P (r) = 0;
6691 /* A static data member declaration is always marked
6692 external when it is declared in-class, even if an
6693 initializer is present. We mimic the non-template
6695 DECL_EXTERNAL (r) = 1;
6697 register_specialization (r, gen_tmpl, argvec);
6698 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6699 SET_DECL_IMPLICIT_INSTANTIATION (r);
6702 register_local_specialization (r, t);
6704 TREE_CHAIN (r) = NULL_TREE;
6713 /* Restore the file and line information. */
6714 input_location = saved_loc;
6719 /* Substitute into the ARG_TYPES of a function type. */
6722 tsubst_arg_types (tree arg_types,
6724 tsubst_flags_t complain,
6727 tree remaining_arg_types;
6730 tree result = NULL_TREE;
6732 if (!arg_types || arg_types == void_list_node)
6735 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6736 args, complain, in_decl);
6737 if (remaining_arg_types == error_mark_node)
6738 return error_mark_node;
6740 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6741 if (type == error_mark_node)
6742 return error_mark_node;
6743 if (VOID_TYPE_P (type))
6745 if (complain & tf_error)
6747 error ("invalid parameter type %qT", type);
6749 error ("in declaration %q+D", in_decl);
6751 return error_mark_node;
6754 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6755 top-level qualifiers as required. */
6756 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6758 /* We do not substitute into default arguments here. The standard
6759 mandates that they be instantiated only when needed, which is
6760 done in build_over_call. */
6761 default_arg = TREE_PURPOSE (arg_types);
6763 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
6765 /* We've instantiated a template before its default arguments
6766 have been parsed. This can happen for a nested template
6767 class, and is not an error unless we require the default
6768 argument in a call of this function. */
6769 result = tree_cons (default_arg, type, remaining_arg_types);
6770 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), result);
6773 result = hash_tree_cons (default_arg, type, remaining_arg_types);
6778 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6779 *not* handle the exception-specification for FNTYPE, because the
6780 initial substitution of explicitly provided template parameters
6781 during argument deduction forbids substitution into the
6782 exception-specification:
6786 All references in the function type of the function template to the
6787 corresponding template parameters are replaced by the specified tem-
6788 plate argument values. If a substitution in a template parameter or
6789 in the function type of the function template results in an invalid
6790 type, type deduction fails. [Note: The equivalent substitution in
6791 exception specifications is done only when the function is instanti-
6792 ated, at which point a program is ill-formed if the substitution
6793 results in an invalid type.] */
6796 tsubst_function_type (tree t,
6798 tsubst_flags_t complain,
6805 /* The TYPE_CONTEXT is not used for function/method types. */
6806 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6808 /* Substitute the return type. */
6809 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6810 if (return_type == error_mark_node)
6811 return error_mark_node;
6812 /* The standard does not presently indicate that creation of a
6813 function type with an invalid return type is a deduction failure.
6814 However, that is clearly analogous to creating an array of "void"
6815 or a reference to a reference. This is core issue #486. */
6816 if (TREE_CODE (return_type) == ARRAY_TYPE
6817 || TREE_CODE (return_type) == FUNCTION_TYPE)
6819 if (complain & tf_error)
6821 if (TREE_CODE (return_type) == ARRAY_TYPE)
6822 error ("function returning an array");
6824 error ("function returning a function");
6826 return error_mark_node;
6829 /* Substitute the argument types. */
6830 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6832 if (arg_types == error_mark_node)
6833 return error_mark_node;
6835 /* Construct a new type node and return it. */
6836 if (TREE_CODE (t) == FUNCTION_TYPE)
6837 fntype = build_function_type (return_type, arg_types);
6840 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6841 if (! IS_AGGR_TYPE (r))
6845 Type deduction may fail for any of the following
6848 -- Attempting to create "pointer to member of T" when T
6849 is not a class type. */
6850 if (complain & tf_error)
6851 error ("creating pointer to member function of non-class type %qT",
6853 return error_mark_node;
6856 fntype = build_method_type_directly (r, return_type,
6857 TREE_CHAIN (arg_types));
6859 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6860 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6865 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6866 ARGS into that specification, and return the substituted
6867 specification. If there is no specification, return NULL_TREE. */
6870 tsubst_exception_specification (tree fntype,
6872 tsubst_flags_t complain,
6878 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6879 new_specs = NULL_TREE;
6882 if (! TREE_VALUE (specs))
6888 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6889 if (spec == error_mark_node)
6891 new_specs = add_exception_specifier (new_specs, spec, complain);
6892 specs = TREE_CHAIN (specs);
6898 /* Substitute into the PARMS of a call-declarator. */
6901 tsubst_call_declarator_parms (tree parms,
6903 tsubst_flags_t complain,
6910 if (!parms || parms == void_list_node)
6913 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6914 args, complain, in_decl);
6916 /* Figure out the type of this parameter. */
6917 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6919 /* Figure out the default argument as well. Note that we use
6920 tsubst_expr since the default argument is really an expression. */
6921 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6923 /* Chain this parameter on to the front of those we have already
6924 processed. We don't use hash_tree_cons because that function
6925 doesn't check TREE_PARMLIST. */
6926 new_parms = tree_cons (defarg, type, new_parms);
6931 /* Take the tree structure T and replace template parameters used
6932 therein with the argument vector ARGS. IN_DECL is an associated
6933 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6934 Issue error and warning messages under control of COMPLAIN. Note
6935 that we must be relatively non-tolerant of extensions here, in
6936 order to preserve conformance; if we allow substitutions that
6937 should not be allowed, we may allow argument deductions that should
6938 not succeed, and therefore report ambiguous overload situations
6939 where there are none. In theory, we could allow the substitution,
6940 but indicate that it should have failed, and allow our caller to
6941 make sure that the right thing happens, but we don't try to do this
6944 This function is used for dealing with types, decls and the like;
6945 for expressions, use tsubst_expr or tsubst_copy. */
6948 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6952 if (t == NULL_TREE || t == error_mark_node
6953 || t == integer_type_node
6954 || t == void_type_node
6955 || t == char_type_node
6956 || t == unknown_type_node
6957 || TREE_CODE (t) == NAMESPACE_DECL)
6961 return tsubst_decl (t, args, complain);
6963 if (TREE_CODE (t) == IDENTIFIER_NODE)
6964 type = IDENTIFIER_TYPE_VALUE (t);
6966 type = TREE_TYPE (t);
6968 gcc_assert (type != unknown_type_node);
6971 && TREE_CODE (t) != TYPENAME_TYPE
6972 && TREE_CODE (t) != IDENTIFIER_NODE
6973 && TREE_CODE (t) != FUNCTION_TYPE
6974 && TREE_CODE (t) != METHOD_TYPE)
6975 type = tsubst (type, args, complain, in_decl);
6976 if (type == error_mark_node)
6977 return error_mark_node;
6979 switch (TREE_CODE (t))
6984 return tsubst_aggr_type (t, args, complain, in_decl,
6985 /*entering_scope=*/0);
6988 case IDENTIFIER_NODE:
7000 if (t == integer_type_node)
7003 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
7004 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
7008 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
7010 /* The array dimension behaves like a non-type template arg,
7011 in that we want to fold it as much as possible. */
7012 max = tsubst_template_arg (omax, args, complain, in_decl);
7013 max = fold_decl_constant_value (max);
7015 if (integer_zerop (omax))
7017 /* Still allow an explicit array of size zero. */
7019 pedwarn ("creating array with size zero");
7021 else if (integer_zerop (max)
7022 || (TREE_CODE (max) == INTEGER_CST
7023 && INT_CST_LT (max, integer_zero_node)))
7027 Type deduction may fail for any of the following
7030 Attempting to create an array with a size that is
7031 zero or negative. */
7032 if (complain & tf_error)
7033 error ("creating array with size zero (%qE)", max);
7035 return error_mark_node;
7038 return compute_array_index_type (NULL_TREE, max);
7041 case TEMPLATE_TYPE_PARM:
7042 case TEMPLATE_TEMPLATE_PARM:
7043 case BOUND_TEMPLATE_TEMPLATE_PARM:
7044 case TEMPLATE_PARM_INDEX:
7049 tree arg = NULL_TREE;
7053 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7054 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7055 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7056 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7058 idx = TEMPLATE_TYPE_IDX (t);
7059 level = TEMPLATE_TYPE_LEVEL (t);
7063 idx = TEMPLATE_PARM_IDX (t);
7064 level = TEMPLATE_PARM_LEVEL (t);
7067 levels = TMPL_ARGS_DEPTH (args);
7068 if (level <= levels)
7069 arg = TMPL_ARG (args, level, idx);
7071 if (arg == error_mark_node)
7072 return error_mark_node;
7073 else if (arg != NULL_TREE)
7075 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7077 gcc_assert (TYPE_P (arg));
7078 return cp_build_qualified_type_real
7079 (arg, cp_type_quals (arg) | cp_type_quals (t),
7080 complain | tf_ignore_bad_quals);
7082 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7084 /* We are processing a type constructed from a
7085 template template parameter. */
7086 tree argvec = tsubst (TYPE_TI_ARGS (t),
7087 args, complain, in_decl);
7088 if (argvec == error_mark_node)
7089 return error_mark_node;
7091 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7092 are resolving nested-types in the signature of a
7093 member function templates. Otherwise ARG is a
7094 TEMPLATE_DECL and is the real template to be
7096 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7097 arg = TYPE_NAME (arg);
7099 r = lookup_template_class (arg,
7102 /*entering_scope=*/0,
7104 return cp_build_qualified_type_real
7105 (r, TYPE_QUALS (t), complain);
7108 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7113 /* This can happen during the attempted tsubst'ing in
7114 unify. This means that we don't yet have any information
7115 about the template parameter in question. */
7118 /* If we get here, we must have been looking at a parm for a
7119 more deeply nested template. Make a new version of this
7120 template parameter, but with a lower level. */
7121 switch (TREE_CODE (t))
7123 case TEMPLATE_TYPE_PARM:
7124 case TEMPLATE_TEMPLATE_PARM:
7125 case BOUND_TEMPLATE_TEMPLATE_PARM:
7126 if (cp_type_quals (t))
7128 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7129 r = cp_build_qualified_type_real
7130 (r, cp_type_quals (t),
7131 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7132 ? tf_ignore_bad_quals : 0));
7137 TEMPLATE_TYPE_PARM_INDEX (r)
7138 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7140 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7141 TYPE_MAIN_VARIANT (r) = r;
7142 TYPE_POINTER_TO (r) = NULL_TREE;
7143 TYPE_REFERENCE_TO (r) = NULL_TREE;
7145 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7147 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7149 if (argvec == error_mark_node)
7150 return error_mark_node;
7152 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7153 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7158 case TEMPLATE_PARM_INDEX:
7159 r = reduce_template_parm_level (t, type, levels);
7171 tree purpose, value, chain;
7173 if (t == void_list_node)
7176 purpose = TREE_PURPOSE (t);
7179 purpose = tsubst (purpose, args, complain, in_decl);
7180 if (purpose == error_mark_node)
7181 return error_mark_node;
7183 value = TREE_VALUE (t);
7186 value = tsubst (value, args, complain, in_decl);
7187 if (value == error_mark_node)
7188 return error_mark_node;
7190 chain = TREE_CHAIN (t);
7191 if (chain && chain != void_type_node)
7193 chain = tsubst (chain, args, complain, in_decl);
7194 if (chain == error_mark_node)
7195 return error_mark_node;
7197 if (purpose == TREE_PURPOSE (t)
7198 && value == TREE_VALUE (t)
7199 && chain == TREE_CHAIN (t))
7201 return hash_tree_cons (purpose, value, chain);
7205 /* We should never be tsubsting a binfo. */
7209 /* A vector of template arguments. */
7211 return tsubst_template_args (t, args, complain, in_decl);
7214 case REFERENCE_TYPE:
7216 enum tree_code code;
7218 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7221 code = TREE_CODE (t);
7226 Type deduction may fail for any of the following
7229 -- Attempting to create a pointer to reference type.
7230 -- Attempting to create a reference to a reference type or
7231 a reference to void. */
7232 if (TREE_CODE (type) == REFERENCE_TYPE
7233 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7235 static location_t last_loc;
7237 /* We keep track of the last time we issued this error
7238 message to avoid spewing a ton of messages during a
7239 single bad template instantiation. */
7240 if (complain & tf_error
7241 #ifdef USE_MAPPED_LOCATION
7242 && last_loc != input_location
7244 && (last_loc.line != input_line
7245 || last_loc.file != input_filename)
7249 if (TREE_CODE (type) == VOID_TYPE)
7250 error ("forming reference to void");
7252 error ("forming %s to reference type %qT",
7253 (code == POINTER_TYPE) ? "pointer" : "reference",
7255 last_loc = input_location;
7258 return error_mark_node;
7260 else if (code == POINTER_TYPE)
7262 r = build_pointer_type (type);
7263 if (TREE_CODE (type) == METHOD_TYPE)
7264 r = build_ptrmemfunc_type (r);
7267 r = build_reference_type (type);
7268 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7270 if (r != error_mark_node)
7271 /* Will this ever be needed for TYPE_..._TO values? */
7278 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7279 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7283 Type deduction may fail for any of the following
7286 -- Attempting to create "pointer to member of T" when T
7287 is not a class type. */
7288 if (complain & tf_error)
7289 error ("creating pointer to member of non-class type %qT", r);
7290 return error_mark_node;
7292 if (TREE_CODE (type) == REFERENCE_TYPE)
7294 if (complain & tf_error)
7295 error ("creating pointer to member reference type %qT", type);
7296 return error_mark_node;
7298 if (TREE_CODE (type) == VOID_TYPE)
7300 if (complain & tf_error)
7301 error ("creating pointer to member of type void");
7302 return error_mark_node;
7304 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7305 if (TREE_CODE (type) == FUNCTION_TYPE)
7307 /* The type of the implicit object parameter gets its
7308 cv-qualifiers from the FUNCTION_TYPE. */
7310 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
7311 cp_type_quals (type));
7313 method_type = build_method_type_directly (this_type,
7315 TYPE_ARG_TYPES (type));
7316 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
7317 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
7321 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7330 fntype = tsubst_function_type (t, args, complain, in_decl);
7331 if (fntype == error_mark_node)
7332 return error_mark_node;
7334 /* Substitute the exception specification. */
7335 specs = tsubst_exception_specification (t, args, complain,
7338 fntype = build_exception_variant (fntype, specs);
7343 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7344 if (domain == error_mark_node)
7345 return error_mark_node;
7347 /* As an optimization, we avoid regenerating the array type if
7348 it will obviously be the same as T. */
7349 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7352 /* These checks should match the ones in grokdeclarator.
7356 The deduction may fail for any of the following reasons:
7358 -- Attempting to create an array with an element type that
7359 is void, a function type, or a reference type, or [DR337]
7360 an abstract class type. */
7361 if (TREE_CODE (type) == VOID_TYPE
7362 || TREE_CODE (type) == FUNCTION_TYPE
7363 || TREE_CODE (type) == REFERENCE_TYPE)
7365 if (complain & tf_error)
7366 error ("creating array of %qT", type);
7367 return error_mark_node;
7369 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7371 if (complain & tf_error)
7372 error ("creating array of %qT, which is an abstract class type",
7374 return error_mark_node;
7377 r = build_cplus_array_type (type, domain);
7384 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7385 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7387 if (e1 == error_mark_node || e2 == error_mark_node)
7388 return error_mark_node;
7390 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
7396 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7397 if (e == error_mark_node)
7398 return error_mark_node;
7400 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
7405 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7406 in_decl, /*entering_scope=*/1);
7407 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7410 if (ctx == error_mark_node || f == error_mark_node)
7411 return error_mark_node;
7413 if (!IS_AGGR_TYPE (ctx))
7415 if (complain & tf_error)
7416 error ("%qT is not a class, struct, or union type", ctx);
7417 return error_mark_node;
7419 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7421 /* Normally, make_typename_type does not require that the CTX
7422 have complete type in order to allow things like:
7424 template <class T> struct S { typename S<T>::X Y; };
7426 But, such constructs have already been resolved by this
7427 point, so here CTX really should have complete type, unless
7428 it's a partial instantiation. */
7429 ctx = complete_type (ctx);
7430 if (!COMPLETE_TYPE_P (ctx))
7432 if (complain & tf_error)
7433 cxx_incomplete_type_error (NULL_TREE, ctx);
7434 return error_mark_node;
7438 f = make_typename_type (ctx, f, typename_type,
7439 (complain & tf_error) | tf_keep_type_decl);
7440 if (f == error_mark_node)
7442 if (TREE_CODE (f) == TYPE_DECL)
7444 complain |= tf_ignore_bad_quals;
7448 if (TREE_CODE (f) != TYPENAME_TYPE)
7450 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7451 error ("%qT resolves to %qT, which is not an enumeration type",
7453 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7454 error ("%qT resolves to %qT, which is is not a class type",
7458 return cp_build_qualified_type_real
7459 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7462 case UNBOUND_CLASS_TEMPLATE:
7464 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7465 in_decl, /*entering_scope=*/1);
7466 tree name = TYPE_IDENTIFIER (t);
7467 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7469 if (ctx == error_mark_node || name == error_mark_node)
7470 return error_mark_node;
7473 parm_list = tsubst_template_parms (parm_list, args, complain);
7474 return make_unbound_class_template (ctx, name, parm_list, complain);
7484 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7485 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7486 if (e1 == error_mark_node || e2 == error_mark_node)
7487 return error_mark_node;
7489 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7494 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7495 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7496 if (e1 == error_mark_node || e2 == error_mark_node)
7497 return error_mark_node;
7499 return build_nt (TREE_CODE (t), e1, e2);
7506 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7507 complain, in_decl));
7508 return cp_build_qualified_type_real (type,
7510 | cp_type_quals (type),
7515 sorry ("use of %qs in template",
7516 tree_code_name [(int) TREE_CODE (t)]);
7517 return error_mark_node;
7521 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7522 type of the expression on the left-hand side of the "." or "->"
7526 tsubst_baselink (tree baselink, tree object_type,
7527 tree args, tsubst_flags_t complain, tree in_decl)
7530 tree qualifying_scope;
7532 tree template_args = 0;
7533 bool template_id_p = false;
7535 /* A baselink indicates a function from a base class. The
7536 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7537 non-dependent types; otherwise, the lookup could not have
7538 succeeded. However, they may indicate bases of the template
7539 class, rather than the instantiated class.
7541 In addition, lookups that were not ambiguous before may be
7542 ambiguous now. Therefore, we perform the lookup again. */
7543 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7544 fns = BASELINK_FUNCTIONS (baselink);
7545 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7547 template_id_p = true;
7548 template_args = TREE_OPERAND (fns, 1);
7549 fns = TREE_OPERAND (fns, 0);
7551 template_args = tsubst_template_args (template_args, args,
7554 name = DECL_NAME (get_first_fn (fns));
7555 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7557 /* If lookup found a single function, mark it as used at this
7558 point. (If it lookup found multiple functions the one selected
7559 later by overload resolution will be marked as used at that
7561 if (BASELINK_P (baselink))
7562 fns = BASELINK_FUNCTIONS (baselink);
7563 if (!template_id_p && !really_overloaded_fn (fns))
7564 mark_used (OVL_CURRENT (fns));
7566 /* Add back the template arguments, if present. */
7567 if (BASELINK_P (baselink) && template_id_p)
7568 BASELINK_FUNCTIONS (baselink)
7569 = build_nt (TEMPLATE_ID_EXPR,
7570 BASELINK_FUNCTIONS (baselink),
7574 object_type = current_class_type;
7575 return adjust_result_of_qualified_name_lookup (baselink,
7580 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7581 true if the qualified-id will be a postfix-expression in-and-of
7582 itself; false if more of the postfix-expression follows the
7583 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7587 tsubst_qualified_id (tree qualified_id, tree args,
7588 tsubst_flags_t complain, tree in_decl,
7589 bool done, bool address_p)
7597 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7599 /* Figure out what name to look up. */
7600 name = TREE_OPERAND (qualified_id, 1);
7601 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7604 template_args = TREE_OPERAND (name, 1);
7606 template_args = tsubst_template_args (template_args, args,
7608 name = TREE_OPERAND (name, 0);
7612 is_template = false;
7613 template_args = NULL_TREE;
7616 /* Substitute into the qualifying scope. When there are no ARGS, we
7617 are just trying to simplify a non-dependent expression. In that
7618 case the qualifying scope may be dependent, and, in any case,
7619 substituting will not help. */
7620 scope = TREE_OPERAND (qualified_id, 0);
7623 scope = tsubst (scope, args, complain, in_decl);
7624 expr = tsubst_copy (name, args, complain, in_decl);
7629 if (dependent_type_p (scope))
7630 return build_nt (SCOPE_REF, scope, expr);
7632 if (!BASELINK_P (name) && !DECL_P (expr))
7634 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7635 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7636 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7638 if (complain & tf_error)
7640 error ("dependent-name %qE is parsed as a non-type, but "
7641 "instantiation yields a type", qualified_id);
7642 inform ("say %<typename %E%> if a type is meant", qualified_id);
7644 return error_mark_node;
7650 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7652 /* Remember that there was a reference to this entity. */
7656 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7658 if (complain & tf_error)
7659 qualified_name_lookup_error (scope,
7660 TREE_OPERAND (qualified_id, 1),
7662 return error_mark_node;
7666 expr = lookup_template_function (expr, template_args);
7668 if (expr == error_mark_node && complain & tf_error)
7669 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7671 else if (TYPE_P (scope))
7673 expr = (adjust_result_of_qualified_name_lookup
7674 (expr, scope, current_class_type));
7675 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7678 expr = convert_from_reference (expr);
7683 /* Like tsubst, but deals with expressions. This function just replaces
7684 template parms; to finish processing the resultant expression, use
7688 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7690 enum tree_code code;
7693 if (t == NULL_TREE || t == error_mark_node)
7696 code = TREE_CODE (t);
7701 r = retrieve_local_specialization (t);
7702 gcc_assert (r != NULL);
7711 if (DECL_TEMPLATE_PARM_P (t))
7712 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7713 /* There is no need to substitute into namespace-scope
7715 if (DECL_NAMESPACE_SCOPE_P (t))
7717 /* If ARGS is NULL, then T is known to be non-dependent. */
7718 if (args == NULL_TREE)
7719 return integral_constant_value (t);
7721 /* Unfortunately, we cannot just call lookup_name here.
7724 template <int I> int f() {
7726 struct S { void g() { E e = a; } };
7729 When we instantiate f<7>::S::g(), say, lookup_name is not
7730 clever enough to find f<7>::a. */
7732 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7733 /*entering_scope=*/0);
7735 for (v = TYPE_VALUES (enum_type);
7738 if (TREE_PURPOSE (v) == DECL_NAME (t))
7739 return TREE_VALUE (v);
7741 /* We didn't find the name. That should never happen; if
7742 name-lookup found it during preliminary parsing, we
7743 should find it again here during instantiation. */
7749 if (DECL_CONTEXT (t))
7753 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7754 /*entering_scope=*/1);
7755 if (ctx != DECL_CONTEXT (t))
7757 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7760 if (complain & tf_error)
7761 error ("using invalid field %qD", t);
7762 return error_mark_node;
7772 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7773 || local_variable_p (t))
7774 t = tsubst (t, args, complain, in_decl);
7779 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7782 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7783 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7784 args, complain, in_decl);
7785 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7786 return tsubst (t, args, complain, in_decl);
7787 else if (DECL_CLASS_SCOPE_P (t)
7788 && uses_template_parms (DECL_CONTEXT (t)))
7790 /* Template template argument like the following example need
7793 template <template <class> class TT> struct C {};
7794 template <class T> struct D {
7795 template <class U> struct E {};
7800 We are processing the template argument `E' in #1 for
7801 the template instantiation #2. Originally, `E' is a
7802 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7803 have to substitute this with one having context `D<int>'. */
7805 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7806 return lookup_field (context, DECL_NAME(t), 0, false);
7809 /* Ordinary template template argument. */
7813 case REINTERPRET_CAST_EXPR:
7814 case CONST_CAST_EXPR:
7815 case STATIC_CAST_EXPR:
7816 case DYNAMIC_CAST_EXPR:
7819 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7820 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7824 case TRUTH_NOT_EXPR:
7827 case UNARY_PLUS_EXPR: /* Unary + */
7836 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7837 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7844 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7845 name = TREE_OPERAND (t, 1);
7846 if (TREE_CODE (name) == BIT_NOT_EXPR)
7848 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7850 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7852 else if (TREE_CODE (name) == SCOPE_REF
7853 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7855 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7857 name = TREE_OPERAND (name, 1);
7858 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7860 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7861 name = build_nt (SCOPE_REF, base, name);
7863 else if (TREE_CODE (name) == BASELINK)
7864 name = tsubst_baselink (name,
7865 non_reference (TREE_TYPE (object)),
7869 name = tsubst_copy (name, args, complain, in_decl);
7870 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7876 case TRUNC_DIV_EXPR:
7878 case FLOOR_DIV_EXPR:
7879 case ROUND_DIV_EXPR:
7880 case EXACT_DIV_EXPR:
7884 case TRUNC_MOD_EXPR:
7885 case FLOOR_MOD_EXPR:
7886 case TRUTH_ANDIF_EXPR:
7887 case TRUTH_ORIF_EXPR:
7888 case TRUTH_AND_EXPR:
7906 case PREDECREMENT_EXPR:
7907 case PREINCREMENT_EXPR:
7908 case POSTDECREMENT_EXPR:
7909 case POSTINCREMENT_EXPR:
7911 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7912 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7917 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7918 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7919 NULL_TREE, NULL_TREE);
7922 return build_nt (code,
7923 tsubst_copy (TREE_OPERAND (t, 0), args,
7925 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7931 case PSEUDO_DTOR_EXPR:
7934 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7935 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7936 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7937 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7944 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7945 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7946 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7947 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7954 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7955 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7956 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7957 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7961 case TEMPLATE_ID_EXPR:
7963 /* Substituted template arguments */
7964 tree fn = TREE_OPERAND (t, 0);
7965 tree targs = TREE_OPERAND (t, 1);
7967 fn = tsubst_copy (fn, args, complain, in_decl);
7969 targs = tsubst_template_args (targs, args, complain, in_decl);
7971 return lookup_template_function (fn, targs);
7976 tree purpose, value, chain;
7978 if (t == void_list_node)
7981 purpose = TREE_PURPOSE (t);
7983 purpose = tsubst_copy (purpose, args, complain, in_decl);
7984 value = TREE_VALUE (t);
7986 value = tsubst_copy (value, args, complain, in_decl);
7987 chain = TREE_CHAIN (t);
7988 if (chain && chain != void_type_node)
7989 chain = tsubst_copy (chain, args, complain, in_decl);
7990 if (purpose == TREE_PURPOSE (t)
7991 && value == TREE_VALUE (t)
7992 && chain == TREE_CHAIN (t))
7994 return tree_cons (purpose, value, chain);
8001 case TEMPLATE_TYPE_PARM:
8002 case TEMPLATE_TEMPLATE_PARM:
8003 case BOUND_TEMPLATE_TEMPLATE_PARM:
8004 case TEMPLATE_PARM_INDEX:
8006 case REFERENCE_TYPE:
8012 case UNBOUND_CLASS_TEMPLATE:
8015 return tsubst (t, args, complain, in_decl);
8017 case IDENTIFIER_NODE:
8018 if (IDENTIFIER_TYPENAME_P (t))
8020 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8021 return mangle_conv_op_name_for_type (new_type);
8027 /* This is handled by tsubst_copy_and_build. */
8031 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8033 tsubst (TREE_TYPE (t), args, complain, in_decl));
8035 case CLEANUP_POINT_EXPR:
8036 /* We shouldn't have built any of these during initial template
8037 generation. Instead, they should be built during instantiation
8038 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8046 /* Like tsubst_copy for expressions, etc. but also does semantic
8050 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8054 if (t == NULL_TREE || t == error_mark_node)
8057 if (EXPR_HAS_LOCATION (t))
8058 input_location = EXPR_LOCATION (t);
8059 if (STATEMENT_CODE_P (TREE_CODE (t)))
8060 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8062 switch (TREE_CODE (t))
8064 case STATEMENT_LIST:
8066 tree_stmt_iterator i;
8067 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8068 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8072 case CTOR_INITIALIZER:
8073 finish_mem_initializers (tsubst_initializer_list
8074 (TREE_OPERAND (t, 0), args));
8078 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8079 args, complain, in_decl));
8083 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8084 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8085 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8087 finish_expr_stmt (tmp);
8091 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8092 args, complain, in_decl));
8100 decl = DECL_EXPR_DECL (t);
8101 if (TREE_CODE (decl) == LABEL_DECL)
8102 finish_label_decl (DECL_NAME (decl));
8103 else if (TREE_CODE (decl) == USING_DECL)
8105 tree scope = USING_DECL_SCOPE (decl);
8106 tree name = DECL_NAME (decl);
8109 scope = tsubst_expr (scope, args, complain, in_decl);
8110 decl = lookup_qualified_name (scope, name,
8111 /*is_type_p=*/false,
8112 /*complain=*/false);
8113 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8114 qualified_name_lookup_error (scope, name, decl);
8116 do_local_using_decl (decl, scope, name);
8120 init = DECL_INITIAL (decl);
8121 decl = tsubst (decl, args, complain, in_decl);
8122 if (decl != error_mark_node)
8125 DECL_INITIAL (decl) = error_mark_node;
8126 /* By marking the declaration as instantiated, we avoid
8127 trying to instantiate it. Since instantiate_decl can't
8128 handle local variables, and since we've already done
8129 all that needs to be done, that's the right thing to
8131 if (TREE_CODE (decl) == VAR_DECL)
8132 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8133 if (TREE_CODE (decl) == VAR_DECL
8134 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8135 /* Anonymous aggregates are a special case. */
8136 finish_anon_union (decl);
8139 maybe_push_decl (decl);
8140 if (TREE_CODE (decl) == VAR_DECL
8141 && DECL_PRETTY_FUNCTION_P (decl))
8143 /* For __PRETTY_FUNCTION__ we have to adjust the
8145 const char *const name
8146 = cxx_printable_name (current_function_decl, 2);
8147 init = cp_fname_init (name, &TREE_TYPE (decl));
8150 init = tsubst_expr (init, args, complain, in_decl);
8151 cp_finish_decl (decl, init, NULL_TREE, 0);
8156 /* A DECL_EXPR can also be used as an expression, in the condition
8157 clause of an if/for/while construct. */
8162 stmt = begin_for_stmt ();
8163 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8164 finish_for_init_stmt (stmt);
8165 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8166 finish_for_cond (tmp, stmt);
8167 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8168 finish_for_expr (tmp, stmt);
8169 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8170 finish_for_stmt (stmt);
8174 stmt = begin_while_stmt ();
8175 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8176 finish_while_stmt_cond (tmp, stmt);
8177 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8178 finish_while_stmt (stmt);
8182 stmt = begin_do_stmt ();
8183 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8184 finish_do_body (stmt);
8185 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8186 finish_do_stmt (tmp, stmt);
8190 stmt = begin_if_stmt ();
8191 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8192 finish_if_stmt_cond (tmp, stmt);
8193 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8194 finish_then_clause (stmt);
8196 if (ELSE_CLAUSE (t))
8198 begin_else_clause (stmt);
8199 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8200 finish_else_clause (stmt);
8203 finish_if_stmt (stmt);
8207 if (BIND_EXPR_BODY_BLOCK (t))
8208 stmt = begin_function_body ();
8210 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8211 ? BCS_TRY_BLOCK : 0);
8213 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8215 if (BIND_EXPR_BODY_BLOCK (t))
8216 finish_function_body (stmt);
8218 finish_compound_stmt (stmt);
8222 finish_break_stmt ();
8226 finish_continue_stmt ();
8230 stmt = begin_switch_stmt ();
8231 tmp = tsubst_expr (SWITCH_STMT_COND (t), args, complain, in_decl);
8232 finish_switch_cond (tmp, stmt);
8233 tsubst_expr (SWITCH_STMT_BODY (t), args, complain, in_decl);
8234 finish_switch_stmt (stmt);
8237 case CASE_LABEL_EXPR:
8238 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8239 tsubst_expr (CASE_HIGH (t), args, complain,
8244 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8248 tmp = GOTO_DESTINATION (t);
8249 if (TREE_CODE (tmp) != LABEL_DECL)
8250 /* Computed goto's must be tsubst'd into. On the other hand,
8251 non-computed gotos must not be; the identifier in question
8252 will have no binding. */
8253 tmp = tsubst_expr (tmp, args, complain, in_decl);
8255 tmp = DECL_NAME (tmp);
8256 finish_goto_stmt (tmp);
8260 tmp = finish_asm_stmt
8261 (ASM_VOLATILE_P (t),
8262 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8263 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8264 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8265 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8267 tree asm_expr = tmp;
8268 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8269 asm_expr = TREE_OPERAND (asm_expr, 0);
8270 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8277 stmt = begin_try_block ();
8278 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8279 finish_cleanup_try_block (stmt);
8280 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8286 if (FN_TRY_BLOCK_P (t))
8287 stmt = begin_function_try_block ();
8289 stmt = begin_try_block ();
8291 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8293 if (FN_TRY_BLOCK_P (t))
8294 finish_function_try_block (stmt);
8296 finish_try_block (stmt);
8298 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8299 if (FN_TRY_BLOCK_P (t))
8300 finish_function_handler_sequence (stmt);
8302 finish_handler_sequence (stmt);
8310 stmt = begin_handler ();
8311 if (HANDLER_PARMS (t))
8313 decl = HANDLER_PARMS (t);
8314 decl = tsubst (decl, args, complain, in_decl);
8315 /* Prevent instantiate_decl from trying to instantiate
8316 this variable. We've already done all that needs to be
8318 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8322 finish_handler_parms (decl, stmt);
8323 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8324 finish_handler (stmt);
8329 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8333 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8335 return tsubst_copy_and_build (t, args, complain, in_decl,
8336 /*function_p=*/false);
8342 /* T is a postfix-expression that is not being used in a function
8343 call. Return the substituted version of T. */
8346 tsubst_non_call_postfix_expression (tree t, tree args,
8347 tsubst_flags_t complain,
8350 if (TREE_CODE (t) == SCOPE_REF)
8351 t = tsubst_qualified_id (t, args, complain, in_decl,
8352 /*done=*/false, /*address_p=*/false);
8354 t = tsubst_copy_and_build (t, args, complain, in_decl,
8355 /*function_p=*/false);
8360 /* Like tsubst but deals with expressions and performs semantic
8361 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8364 tsubst_copy_and_build (tree t,
8366 tsubst_flags_t complain,
8370 #define RECUR(NODE) \
8371 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8375 if (t == NULL_TREE || t == error_mark_node)
8378 switch (TREE_CODE (t))
8383 case IDENTIFIER_NODE:
8387 tree qualifying_class;
8388 bool non_integral_constant_expression_p;
8389 const char *error_msg;
8391 if (IDENTIFIER_TYPENAME_P (t))
8393 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8394 t = mangle_conv_op_name_for_type (new_type);
8397 /* Look up the name. */
8398 decl = lookup_name (t, 0);
8400 /* By convention, expressions use ERROR_MARK_NODE to indicate
8401 failure, not NULL_TREE. */
8402 if (decl == NULL_TREE)
8403 decl = error_mark_node;
8405 decl = finish_id_expression (t, decl, NULL_TREE,
8408 /*integral_constant_expression_p=*/false,
8409 /*allow_non_integral_constant_expression_p=*/false,
8410 &non_integral_constant_expression_p,
8414 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8415 decl = unqualified_name_lookup_error (decl);
8419 case TEMPLATE_ID_EXPR:
8422 tree template = RECUR (TREE_OPERAND (t, 0));
8423 tree targs = TREE_OPERAND (t, 1);
8426 targs = tsubst_template_args (targs, args, complain, in_decl);
8428 if (TREE_CODE (template) == COMPONENT_REF)
8430 object = TREE_OPERAND (template, 0);
8431 template = TREE_OPERAND (template, 1);
8435 template = lookup_template_function (template, targs);
8438 return build3 (COMPONENT_REF, TREE_TYPE (template),
8439 object, template, NULL_TREE);
8446 tree r = RECUR (TREE_OPERAND (t, 0));
8448 if (REFERENCE_REF_P (t))
8450 /* A type conversion to reference type will be enclosed in
8451 such an indirect ref, but the substitution of the cast
8452 will have also added such an indirect ref. */
8453 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8454 r = convert_from_reference (r);
8457 r = build_x_indirect_ref (r, "unary *");
8463 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8464 RECUR (TREE_OPERAND (t, 0)));
8467 return build_functional_cast
8468 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8469 RECUR (TREE_OPERAND (t, 0)));
8471 case REINTERPRET_CAST_EXPR:
8472 return build_reinterpret_cast
8473 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8474 RECUR (TREE_OPERAND (t, 0)));
8476 case CONST_CAST_EXPR:
8477 return build_const_cast
8478 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8479 RECUR (TREE_OPERAND (t, 0)));
8481 case DYNAMIC_CAST_EXPR:
8482 return build_dynamic_cast
8483 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8484 RECUR (TREE_OPERAND (t, 0)));
8486 case STATIC_CAST_EXPR:
8487 return build_static_cast
8488 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8489 RECUR (TREE_OPERAND (t, 0)));
8491 case POSTDECREMENT_EXPR:
8492 case POSTINCREMENT_EXPR:
8493 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8494 args, complain, in_decl);
8495 return build_x_unary_op (TREE_CODE (t), op1);
8497 case PREDECREMENT_EXPR:
8498 case PREINCREMENT_EXPR:
8502 case TRUTH_NOT_EXPR:
8503 case UNARY_PLUS_EXPR: /* Unary + */
8506 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8509 op1 = TREE_OPERAND (t, 0);
8510 if (TREE_CODE (op1) == SCOPE_REF)
8511 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8512 /*done=*/true, /*address_p=*/true);
8514 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8516 if (TREE_CODE (op1) == LABEL_DECL)
8517 return finish_label_address_expr (DECL_NAME (op1));
8518 return build_x_unary_op (ADDR_EXPR, op1);
8523 case TRUNC_DIV_EXPR:
8525 case FLOOR_DIV_EXPR:
8526 case ROUND_DIV_EXPR:
8527 case EXACT_DIV_EXPR:
8531 case TRUNC_MOD_EXPR:
8532 case FLOOR_MOD_EXPR:
8533 case TRUTH_ANDIF_EXPR:
8534 case TRUTH_ORIF_EXPR:
8535 case TRUTH_AND_EXPR:
8551 return build_x_binary_op
8553 RECUR (TREE_OPERAND (t, 0)),
8554 RECUR (TREE_OPERAND (t, 1)),
8555 /*overloaded_p=*/NULL);
8558 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8559 /*address_p=*/false);
8561 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8562 args, complain, in_decl);
8563 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8564 /*overloaded_p=*/NULL);
8568 op1 = TREE_OPERAND (t, 0);
8571 /* When there are no ARGS, we are trying to evaluate a
8572 non-dependent expression from the parser. Trying to do
8573 the substitutions may not work. */
8575 op1 = TREE_TYPE (op1);
8584 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8586 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8590 tree r = build_x_modify_expr
8591 (RECUR (TREE_OPERAND (t, 0)),
8592 TREE_CODE (TREE_OPERAND (t, 1)),
8593 RECUR (TREE_OPERAND (t, 2)));
8594 /* TREE_NO_WARNING must be set if either the expression was
8595 parenthesized or it uses an operator such as >>= rather
8596 than plain assignment. In the former case, it was already
8597 set and must be copied. In the latter case,
8598 build_x_modify_expr sets it and it must not be reset
8600 if (TREE_NO_WARNING (t))
8601 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8606 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8607 args, complain, in_decl);
8608 /* Remember that there was a reference to this entity. */
8611 return build_x_arrow (op1);
8615 (RECUR (TREE_OPERAND (t, 0)),
8616 RECUR (TREE_OPERAND (t, 1)),
8617 RECUR (TREE_OPERAND (t, 2)),
8618 RECUR (TREE_OPERAND (t, 3)),
8619 NEW_EXPR_USE_GLOBAL (t));
8622 return delete_sanity
8623 (RECUR (TREE_OPERAND (t, 0)),
8624 RECUR (TREE_OPERAND (t, 1)),
8625 DELETE_EXPR_USE_VEC (t),
8626 DELETE_EXPR_USE_GLOBAL (t));
8629 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8630 RECUR (TREE_OPERAND (t, 1)));
8639 function = TREE_OPERAND (t, 0);
8640 /* When we parsed the expression, we determined whether or
8641 not Koenig lookup should be performed. */
8642 koenig_p = KOENIG_LOOKUP_P (t);
8643 if (TREE_CODE (function) == SCOPE_REF)
8646 function = tsubst_qualified_id (function, args, complain, in_decl,
8648 /*address_p=*/false);
8652 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8653 && (TREE_CODE (TREE_OPERAND (function, 1))
8655 function = tsubst_copy_and_build (function, args, complain,
8658 if (BASELINK_P (function))
8662 call_args = RECUR (TREE_OPERAND (t, 1));
8664 /* We do not perform argument-dependent lookup if normal
8665 lookup finds a non-function, in accordance with the
8666 expected resolution of DR 218. */
8668 && ((is_overloaded_fn (function)
8669 /* If lookup found a member function, the Koenig lookup is
8670 not appropriate, even if an unqualified-name was used
8671 to denote the function. */
8672 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8673 || TREE_CODE (function) == IDENTIFIER_NODE))
8674 function = perform_koenig_lookup (function, call_args);
8676 if (TREE_CODE (function) == IDENTIFIER_NODE)
8678 unqualified_name_lookup_error (function);
8679 return error_mark_node;
8682 /* Remember that there was a reference to this entity. */
8683 if (DECL_P (function))
8684 mark_used (function);
8686 if (TREE_CODE (function) == OFFSET_REF)
8687 return build_offset_ref_call_from_tree (function, call_args);
8688 if (TREE_CODE (function) == COMPONENT_REF)
8690 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8691 return finish_call_expr (function, call_args,
8692 /*disallow_virtual=*/false,
8693 /*koenig_p=*/false);
8695 return (build_new_method_call
8696 (TREE_OPERAND (function, 0),
8697 TREE_OPERAND (function, 1),
8698 call_args, NULL_TREE,
8699 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8701 return finish_call_expr (function, call_args,
8702 /*disallow_virtual=*/qualified_p,
8707 return build_x_conditional_expr
8708 (RECUR (TREE_OPERAND (t, 0)),
8709 RECUR (TREE_OPERAND (t, 1)),
8710 RECUR (TREE_OPERAND (t, 2)));
8712 case PSEUDO_DTOR_EXPR:
8713 return finish_pseudo_destructor_expr
8714 (RECUR (TREE_OPERAND (t, 0)),
8715 RECUR (TREE_OPERAND (t, 1)),
8716 RECUR (TREE_OPERAND (t, 2)));
8720 tree purpose, value, chain;
8722 if (t == void_list_node)
8725 purpose = TREE_PURPOSE (t);
8727 purpose = RECUR (purpose);
8728 value = TREE_VALUE (t);
8730 value = RECUR (value);
8731 chain = TREE_CHAIN (t);
8732 if (chain && chain != void_type_node)
8733 chain = RECUR (chain);
8734 if (purpose == TREE_PURPOSE (t)
8735 && value == TREE_VALUE (t)
8736 && chain == TREE_CHAIN (t))
8738 return tree_cons (purpose, value, chain);
8746 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8747 args, complain, in_decl);
8748 /* Remember that there was a reference to this entity. */
8749 if (DECL_P (object))
8752 member = TREE_OPERAND (t, 1);
8753 if (BASELINK_P (member))
8754 member = tsubst_baselink (member,
8755 non_reference (TREE_TYPE (object)),
8756 args, complain, in_decl);
8758 member = tsubst_copy (member, args, complain, in_decl);
8760 if (member == error_mark_node)
8761 return error_mark_node;
8762 else if (!CLASS_TYPE_P (TREE_TYPE (object)))
8764 if (TREE_CODE (member) == BIT_NOT_EXPR)
8765 return finish_pseudo_destructor_expr (object,
8767 TREE_TYPE (object));
8768 else if (TREE_CODE (member) == SCOPE_REF
8769 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8770 return finish_pseudo_destructor_expr (object,
8772 TREE_TYPE (object));
8774 else if (TREE_CODE (member) == SCOPE_REF
8775 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8780 /* Lookup the template functions now that we know what the
8782 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8783 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8784 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8785 /*is_type_p=*/false,
8786 /*complain=*/false);
8787 if (BASELINK_P (member))
8789 BASELINK_FUNCTIONS (member)
8790 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8792 member = (adjust_result_of_qualified_name_lookup
8793 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8794 TREE_TYPE (object)));
8798 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8800 return error_mark_node;
8803 else if (TREE_CODE (member) == SCOPE_REF
8804 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8805 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8807 if (complain & tf_error)
8809 if (TYPE_P (TREE_OPERAND (member, 0)))
8810 error ("%qT is not a class or namespace",
8811 TREE_OPERAND (member, 0));
8813 error ("%qD is not a class or namespace",
8814 TREE_OPERAND (member, 0));
8816 return error_mark_node;
8818 else if (TREE_CODE (member) == FIELD_DECL)
8819 return finish_non_static_data_member (member, object, NULL_TREE);
8821 return finish_class_member_access_expr (object, member);
8826 (RECUR (TREE_OPERAND (t, 0)));
8830 VEC(constructor_elt,gc) *n;
8831 constructor_elt *ce;
8832 unsigned HOST_WIDE_INT idx;
8834 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8835 bool process_index_p;
8837 /* digest_init will do the wrong thing if we let it. */
8838 if (type && TYPE_PTRMEMFUNC_P (type))
8841 /* We do not want to process the index of aggregate
8842 initializers as they are identifier nodes which will be
8843 looked up by digest_init. */
8844 process_index_p = !(type && IS_AGGR_TYPE (type));
8846 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
8847 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
8849 if (ce->index && process_index_p)
8850 ce->index = RECUR (ce->index);
8851 ce->value = RECUR (ce->value);
8854 r = build_constructor (NULL_TREE, n);
8855 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8858 return digest_init (type, r);
8864 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8865 if (TYPE_P (operand_0))
8866 return get_typeid (operand_0);
8867 return build_typeid (operand_0);
8877 tree r = tsubst_copy (t, args, complain, in_decl);
8879 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
8880 /* If the original type was a reference, we'll be wrapped in
8881 the appropriate INDIRECT_REF. */
8882 r = convert_from_reference (r);
8887 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8888 tsubst_copy (TREE_TYPE (t), args, complain,
8892 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8896 tree old_stmt_expr = cur_stmt_expr;
8897 tree stmt_expr = begin_stmt_expr ();
8899 cur_stmt_expr = stmt_expr;
8900 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8901 stmt_expr = finish_stmt_expr (stmt_expr, false);
8902 cur_stmt_expr = old_stmt_expr;
8908 t = tsubst_copy (t, args, complain, in_decl);
8909 /* As in finish_id_expression, we resolve enumeration constants
8910 to their underlying values. */
8911 if (TREE_CODE (t) == CONST_DECL)
8912 return DECL_INITIAL (t);
8916 /* Handle Objective-C++ constructs, if appropriate. */
8919 = objcp_tsubst_copy_and_build (t, args, complain,
8920 in_decl, /*function_p=*/false);
8924 return tsubst_copy (t, args, complain, in_decl);
8930 /* Verify that the instantiated ARGS are valid. For type arguments,
8931 make sure that the type's linkage is ok. For non-type arguments,
8932 make sure they are constants if they are integral or enumerations.
8933 Emit an error under control of COMPLAIN, and return TRUE on error. */
8936 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8938 int ix, len = DECL_NTPARMS (tmpl);
8939 bool result = false;
8940 bool error_p = complain & tf_error;
8942 for (ix = 0; ix != len; ix++)
8944 tree t = TREE_VEC_ELT (args, ix);
8948 /* [basic.link]: A name with no linkage (notably, the name
8949 of a class or enumeration declared in a local scope)
8950 shall not be used to declare an entity with linkage.
8951 This implies that names with no linkage cannot be used as
8952 template arguments. */
8953 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8957 if (TYPE_ANONYMOUS_P (nt))
8958 error ("%qT is/uses anonymous type", t);
8960 error ("%qT uses local type %qT", t, nt);
8964 /* In order to avoid all sorts of complications, we do not
8965 allow variably-modified types as template arguments. */
8966 else if (variably_modified_type_p (t, NULL_TREE))
8968 if (complain & tf_error)
8969 error ("%qT is a variably modified type", t);
8973 /* A non-type argument of integral or enumerated type must be a
8975 else if (TREE_TYPE (t)
8976 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
8977 && !TREE_CONSTANT (t))
8979 if (complain & tf_error)
8980 error ("integral expression %qE is not constant", t);
8984 if (result && error_p)
8985 error (" trying to instantiate %qD", tmpl);
8989 /* Instantiate the indicated variable or function template TMPL with
8990 the template arguments in TARG_PTR. */
8993 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
8999 if (tmpl == error_mark_node)
9000 return error_mark_node;
9002 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
9004 /* If this function is a clone, handle it specially. */
9005 if (DECL_CLONED_FUNCTION_P (tmpl))
9010 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
9012 if (spec == error_mark_node)
9013 return error_mark_node;
9015 /* Look for the clone. */
9016 FOR_EACH_CLONE (clone, spec)
9017 if (DECL_NAME (clone) == DECL_NAME (tmpl))
9019 /* We should always have found the clone by now. */
9024 /* Check to see if we already have this specialization. */
9025 spec = retrieve_specialization (tmpl, targ_ptr,
9026 /*class_specializations_p=*/false);
9027 if (spec != NULL_TREE)
9030 gen_tmpl = most_general_template (tmpl);
9031 if (tmpl != gen_tmpl)
9033 /* The TMPL is a partial instantiation. To get a full set of
9034 arguments we must add the arguments used to perform the
9035 partial instantiation. */
9036 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9039 /* Check to see if we already have this specialization. */
9040 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9041 /*class_specializations_p=*/false);
9042 if (spec != NULL_TREE)
9046 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9048 return error_mark_node;
9050 /* We are building a FUNCTION_DECL, during which the access of its
9051 parameters and return types have to be checked. However this
9052 FUNCTION_DECL which is the desired context for access checking
9053 is not built yet. We solve this chicken-and-egg problem by
9054 deferring all checks until we have the FUNCTION_DECL. */
9055 push_deferring_access_checks (dk_deferred);
9057 /* Substitute template parameters. */
9058 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9059 targ_ptr, complain, gen_tmpl);
9061 /* Now we know the specialization, compute access previously
9063 push_access_scope (fndecl);
9064 perform_deferred_access_checks ();
9065 pop_access_scope (fndecl);
9066 pop_deferring_access_checks ();
9068 /* The DECL_TI_TEMPLATE should always be the immediate parent
9069 template, not the most general template. */
9070 DECL_TI_TEMPLATE (fndecl) = tmpl;
9072 /* If we've just instantiated the main entry point for a function,
9073 instantiate all the alternate entry points as well. We do this
9074 by cloning the instantiation of the main entry point, not by
9075 instantiating the template clones. */
9076 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9077 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9082 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9083 arguments that are being used when calling it. TARGS is a vector
9084 into which the deduced template arguments are placed.
9086 Return zero for success, 2 for an incomplete match that doesn't resolve
9087 all the types, and 1 for complete failure. An error message will be
9088 printed only for an incomplete match.
9090 If FN is a conversion operator, or we are trying to produce a specific
9091 specialization, RETURN_TYPE is the return type desired.
9093 The EXPLICIT_TARGS are explicit template arguments provided via a
9096 The parameter STRICT is one of:
9099 We are deducing arguments for a function call, as in
9103 We are deducing arguments for a conversion function, as in
9107 We are deducing arguments when doing an explicit instantiation
9108 as in [temp.explicit], when determining an explicit specialization
9109 as in [temp.expl.spec], or when taking the address of a function
9110 template, as in [temp.deduct.funcaddr]. */
9113 fn_type_unification (tree fn,
9114 tree explicit_targs,
9118 unification_kind_t strict)
9124 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9126 fntype = TREE_TYPE (fn);
9131 The specified template arguments must match the template
9132 parameters in kind (i.e., type, nontype, template), and there
9133 must not be more arguments than there are parameters;
9134 otherwise type deduction fails.
9136 Nontype arguments must match the types of the corresponding
9137 nontype template parameters, or must be convertible to the
9138 types of the corresponding nontype parameters as specified in
9139 _temp.arg.nontype_, otherwise type deduction fails.
9141 All references in the function type of the function template
9142 to the corresponding template parameters are replaced by the
9143 specified template argument values. If a substitution in a
9144 template parameter or in the function type of the function
9145 template results in an invalid type, type deduction fails. */
9147 tree converted_args;
9150 if (explicit_targs == error_mark_node)
9154 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9155 explicit_targs, NULL_TREE, tf_none,
9156 /*require_all_arguments=*/0));
9157 if (converted_args == error_mark_node)
9160 /* Substitute the explicit args into the function type. This is
9161 necessary so that, for instance, explicitly declared function
9162 arguments can match null pointed constants. If we were given
9163 an incomplete set of explicit args, we must not do semantic
9164 processing during substitution as we could create partial
9166 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9167 processing_template_decl += incomplete;
9168 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9169 processing_template_decl -= incomplete;
9171 if (fntype == error_mark_node)
9174 /* Place the explicitly specified arguments in TARGS. */
9175 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9176 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9179 parms = TYPE_ARG_TYPES (fntype);
9180 /* Never do unification on the 'this' parameter. */
9181 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9182 parms = TREE_CHAIN (parms);
9186 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9187 args = tree_cons (NULL_TREE, return_type, args);
9190 /* We allow incomplete unification without an error message here
9191 because the standard doesn't seem to explicitly prohibit it. Our
9192 callers must be ready to deal with unification failures in any
9194 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9195 targs, parms, args, /*subr=*/0,
9199 /* All is well so far. Now, check:
9203 When all template arguments have been deduced, all uses of
9204 template parameters in nondeduced contexts are replaced with
9205 the corresponding deduced argument values. If the
9206 substitution results in an invalid type, as described above,
9207 type deduction fails. */
9208 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9215 /* Adjust types before performing type deduction, as described in
9216 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9217 sections are symmetric. PARM is the type of a function parameter
9218 or the return type of the conversion function. ARG is the type of
9219 the argument passed to the call, or the type of the value
9220 initialized with the result of the conversion function. */
9223 maybe_adjust_types_for_deduction (unification_kind_t strict,
9236 /* Swap PARM and ARG throughout the remainder of this
9237 function; the handling is precisely symmetric since PARM
9238 will initialize ARG rather than vice versa. */
9246 /* There is nothing to do in this case. */
9253 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9255 /* [temp.deduct.call]
9257 If P is not a reference type:
9259 --If A is an array type, the pointer type produced by the
9260 array-to-pointer standard conversion (_conv.array_) is
9261 used in place of A for type deduction; otherwise,
9263 --If A is a function type, the pointer type produced by
9264 the function-to-pointer standard conversion
9265 (_conv.func_) is used in place of A for type deduction;
9268 --If A is a cv-qualified type, the top level
9269 cv-qualifiers of A's type are ignored for type
9271 if (TREE_CODE (*arg) == ARRAY_TYPE)
9272 *arg = build_pointer_type (TREE_TYPE (*arg));
9273 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9274 *arg = build_pointer_type (*arg);
9276 *arg = TYPE_MAIN_VARIANT (*arg);
9279 /* [temp.deduct.call]
9281 If P is a cv-qualified type, the top level cv-qualifiers
9282 of P's type are ignored for type deduction. If P is a
9283 reference type, the type referred to by P is used for
9285 *parm = TYPE_MAIN_VARIANT (*parm);
9286 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9288 *parm = TREE_TYPE (*parm);
9289 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9292 /* DR 322. For conversion deduction, remove a reference type on parm
9293 too (which has been swapped into ARG). */
9294 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9295 *arg = TREE_TYPE (*arg);
9300 /* Most parms like fn_type_unification.
9302 If SUBR is 1, we're being called recursively (to unify the
9303 arguments of a function or method parameter of a function
9304 template). If IS_METHOD is true, XPARMS are the parms of a
9305 member function, and special rules apply to cv qualification
9306 deduction on the this parameter. */
9309 type_unification_real (tree tparms,
9314 unification_kind_t strict,
9319 int ntparms = TREE_VEC_LENGTH (tparms);
9321 int saw_undeduced = 0;
9324 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9325 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9326 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9327 gcc_assert (ntparms > 0);
9332 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9333 | UNIFY_ALLOW_DERIVED);
9337 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9341 sub_strict = UNIFY_ALLOW_NONE;
9352 while (parms && parms != void_list_node
9353 && args && args != void_list_node)
9355 parm = TREE_VALUE (parms);
9356 parms = TREE_CHAIN (parms);
9357 arg = TREE_VALUE (args);
9358 args = TREE_CHAIN (args);
9360 if (arg == error_mark_node)
9362 if (arg == unknown_type_node)
9363 /* We can't deduce anything from this, but we might get all the
9364 template args from other function args. */
9369 /* The cv qualifiers on the this pointer argument must match
9370 exactly. We cannot deduce a T as const X against a const
9371 member function for instance. */
9372 gcc_assert (TREE_CODE (parm) == POINTER_TYPE);
9373 gcc_assert (TREE_CODE (arg) == POINTER_TYPE);
9374 /* The restrict qualifier will be on the pointer. */
9375 if (cp_type_quals (parm) != cp_type_quals (arg))
9377 parm = TREE_TYPE (parm);
9378 arg = TREE_TYPE (arg);
9379 if (cp_type_quals (parm) != cp_type_quals (arg))
9382 parm = TYPE_MAIN_VARIANT (parm);
9383 arg = TYPE_MAIN_VARIANT (arg);
9387 /* Conversions will be performed on a function argument that
9388 corresponds with a function parameter that contains only
9389 non-deducible template parameters and explicitly specified
9390 template parameters. */
9391 if (!uses_template_parms (parm))
9396 type = TREE_TYPE (arg);
9400 if (same_type_p (parm, type))
9402 if (strict != DEDUCE_EXACT
9403 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg))
9411 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9412 if (type_unknown_p (arg))
9414 /* [temp.deduct.type] A template-argument can be deduced from
9415 a pointer to function or pointer to member function
9416 argument if the set of overloaded functions does not
9417 contain function templates and at most one of a set of
9418 overloaded functions provides a unique match. */
9420 if (resolve_overloaded_unification
9421 (tparms, targs, parm, arg, strict, sub_strict)
9426 arg = TREE_TYPE (arg);
9427 if (arg == error_mark_node)
9432 int arg_strict = sub_strict;
9435 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9437 if (unify (tparms, targs, parm, arg, arg_strict))
9442 /* Fail if we've reached the end of the parm list, and more args
9443 are present, and the parm list isn't variadic. */
9444 if (args && args != void_list_node && parms == void_list_node)
9446 /* Fail if parms are left and they don't have default values. */
9447 if (parms && parms != void_list_node
9448 && TREE_PURPOSE (parms) == NULL_TREE)
9452 for (i = 0; i < ntparms; i++)
9453 if (!TREE_VEC_ELT (targs, i))
9455 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9457 /* If this is an undeduced nontype parameter that depends on
9458 a type parameter, try another pass; its type may have been
9459 deduced from a later argument than the one from which
9460 this parameter can be deduced. */
9461 if (TREE_CODE (tparm) == PARM_DECL
9462 && uses_template_parms (TREE_TYPE (tparm))
9463 && !saw_undeduced++)
9472 /* Subroutine of type_unification_real. Args are like the variables at the
9473 call site. ARG is an overloaded function (or template-id); we try
9474 deducing template args from each of the overloads, and if only one
9475 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9478 resolve_overloaded_unification (tree tparms,
9482 unification_kind_t strict,
9485 tree tempargs = copy_node (targs);
9489 if (TREE_CODE (arg) == ADDR_EXPR)
9491 arg = TREE_OPERAND (arg, 0);
9497 if (TREE_CODE (arg) == COMPONENT_REF)
9498 /* Handle `&x' where `x' is some static or non-static member
9500 arg = TREE_OPERAND (arg, 1);
9502 if (TREE_CODE (arg) == OFFSET_REF)
9503 arg = TREE_OPERAND (arg, 1);
9505 /* Strip baselink information. */
9506 if (BASELINK_P (arg))
9507 arg = BASELINK_FUNCTIONS (arg);
9509 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9511 /* If we got some explicit template args, we need to plug them into
9512 the affected templates before we try to unify, in case the
9513 explicit args will completely resolve the templates in question. */
9515 tree expl_subargs = TREE_OPERAND (arg, 1);
9516 arg = TREE_OPERAND (arg, 0);
9518 for (; arg; arg = OVL_NEXT (arg))
9520 tree fn = OVL_CURRENT (arg);
9523 if (TREE_CODE (fn) != TEMPLATE_DECL)
9526 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
9527 expl_subargs, /*check_ret=*/false);
9530 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9531 good += try_one_overload (tparms, targs, tempargs, parm,
9532 elem, strict, sub_strict, addr_p);
9538 gcc_assert (TREE_CODE (arg) == OVERLOAD
9539 || TREE_CODE (arg) == FUNCTION_DECL);
9541 for (; arg; arg = OVL_NEXT (arg))
9542 good += try_one_overload (tparms, targs, tempargs, parm,
9543 TREE_TYPE (OVL_CURRENT (arg)),
9544 strict, sub_strict, addr_p);
9547 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9548 to function or pointer to member function argument if the set of
9549 overloaded functions does not contain function templates and at most
9550 one of a set of overloaded functions provides a unique match.
9552 So if we found multiple possibilities, we return success but don't
9557 int i = TREE_VEC_LENGTH (targs);
9559 if (TREE_VEC_ELT (tempargs, i))
9560 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9568 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9569 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9570 different overloads deduce different arguments for a given parm.
9571 ADDR_P is true if the expression for which deduction is being
9572 performed was of the form "& fn" rather than simply "fn".
9574 Returns 1 on success. */
9577 try_one_overload (tree tparms,
9582 unification_kind_t strict,
9590 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9591 to function or pointer to member function argument if the set of
9592 overloaded functions does not contain function templates and at most
9593 one of a set of overloaded functions provides a unique match.
9595 So if this is a template, just return success. */
9597 if (uses_template_parms (arg))
9600 if (TREE_CODE (arg) == METHOD_TYPE)
9601 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9603 arg = build_pointer_type (arg);
9605 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9607 /* We don't copy orig_targs for this because if we have already deduced
9608 some template args from previous args, unify would complain when we
9609 try to deduce a template parameter for the same argument, even though
9610 there isn't really a conflict. */
9611 nargs = TREE_VEC_LENGTH (targs);
9612 tempargs = make_tree_vec (nargs);
9614 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9617 /* First make sure we didn't deduce anything that conflicts with
9618 explicitly specified args. */
9619 for (i = nargs; i--; )
9621 tree elt = TREE_VEC_ELT (tempargs, i);
9622 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9626 else if (uses_template_parms (elt))
9627 /* Since we're unifying against ourselves, we will fill in
9628 template args used in the function parm list with our own
9629 template parms. Discard them. */
9630 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9631 else if (oldelt && !template_args_equal (oldelt, elt))
9635 for (i = nargs; i--; )
9637 tree elt = TREE_VEC_ELT (tempargs, i);
9640 TREE_VEC_ELT (targs, i) = elt;
9646 /* Verify that nondeduce template argument agrees with the type
9647 obtained from argument deduction. Return nonzero if the
9652 struct A { typedef int X; };
9653 template <class T, class U> struct C {};
9654 template <class T> struct C<T, typename T::X> {};
9656 Then with the instantiation `C<A, int>', we can deduce that
9657 `T' is `A' but unify () does not check whether `typename T::X'
9658 is `int'. This function ensure that they agree.
9660 TARGS, PARMS are the same as the arguments of unify.
9661 ARGS contains template arguments from all levels. */
9664 verify_class_unification (tree targs, tree parms, tree args)
9666 parms = tsubst (parms, add_outermost_template_args (args, targs),
9667 tf_none, NULL_TREE);
9668 if (parms == error_mark_node)
9671 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9674 /* PARM is a template class (perhaps with unbound template
9675 parameters). ARG is a fully instantiated type. If ARG can be
9676 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9677 TARGS are as for unify. */
9680 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9684 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9685 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9686 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9689 /* We need to make a new template argument vector for the call to
9690 unify. If we used TARGS, we'd clutter it up with the result of
9691 the attempted unification, even if this class didn't work out.
9692 We also don't want to commit ourselves to all the unifications
9693 we've already done, since unification is supposed to be done on
9694 an argument-by-argument basis. In other words, consider the
9695 following pathological case:
9697 template <int I, int J, int K>
9700 template <int I, int J>
9701 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9703 template <int I, int J, int K>
9704 void f(S<I, J, K>, S<I, I, I>);
9713 Now, by the time we consider the unification involving `s2', we
9714 already know that we must have `f<0, 0, 0>'. But, even though
9715 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9716 because there are two ways to unify base classes of S<0, 1, 2>
9717 with S<I, I, I>. If we kept the already deduced knowledge, we
9718 would reject the possibility I=1. */
9719 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9721 /* If unification failed, we're done. */
9722 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9723 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9729 /* Given a template type PARM and a class type ARG, find the unique
9730 base type in ARG that is an instance of PARM. We do not examine
9731 ARG itself; only its base-classes. If there is not exactly one
9732 appropriate base class, return NULL_TREE. PARM may be the type of
9733 a partial specialization, as well as a plain template type. Used
9737 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9739 tree rval = NULL_TREE;
9742 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9744 binfo = TYPE_BINFO (complete_type (arg));
9746 /* The type could not be completed. */
9749 /* Walk in inheritance graph order. The search order is not
9750 important, and this avoids multiple walks of virtual bases. */
9751 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9753 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9757 /* If there is more than one satisfactory baseclass, then:
9761 If they yield more than one possible deduced A, the type
9765 if (rval && !same_type_p (r, rval))
9775 /* Returns the level of DECL, which declares a template parameter. */
9778 template_decl_level (tree decl)
9780 switch (TREE_CODE (decl))
9784 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9787 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9795 /* Decide whether ARG can be unified with PARM, considering only the
9796 cv-qualifiers of each type, given STRICT as documented for unify.
9797 Returns nonzero iff the unification is OK on that basis. */
9800 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9802 int arg_quals = cp_type_quals (arg);
9803 int parm_quals = cp_type_quals (parm);
9805 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9806 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9808 /* Although a CVR qualifier is ignored when being applied to a
9809 substituted template parameter ([8.3.2]/1 for example), that
9810 does not apply during deduction [14.8.2.4]/1, (even though
9811 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9812 this). Except when we're allowing additional CV qualifiers
9813 at the outer level [14.8.2.1]/3,1st bullet. */
9814 if ((TREE_CODE (arg) == REFERENCE_TYPE
9815 || TREE_CODE (arg) == FUNCTION_TYPE
9816 || TREE_CODE (arg) == METHOD_TYPE)
9817 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9820 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9821 && (parm_quals & TYPE_QUAL_RESTRICT))
9825 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9826 && (arg_quals & parm_quals) != parm_quals)
9829 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9830 && (parm_quals & arg_quals) != arg_quals)
9836 /* Takes parameters as for type_unification. Returns 0 if the
9837 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9838 bitwise or of the following flags:
9841 Require an exact match between PARM and ARG.
9842 UNIFY_ALLOW_MORE_CV_QUAL:
9843 Allow the deduced ARG to be more cv-qualified (by qualification
9844 conversion) than ARG.
9845 UNIFY_ALLOW_LESS_CV_QUAL:
9846 Allow the deduced ARG to be less cv-qualified than ARG.
9847 UNIFY_ALLOW_DERIVED:
9848 Allow the deduced ARG to be a template base class of ARG,
9849 or a pointer to a template base class of the type pointed to by
9851 UNIFY_ALLOW_INTEGER:
9852 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9853 case for more information.
9854 UNIFY_ALLOW_OUTER_LEVEL:
9855 This is the outermost level of a deduction. Used to determine validity
9856 of qualification conversions. A valid qualification conversion must
9857 have const qualified pointers leading up to the inner type which
9858 requires additional CV quals, except at the outer level, where const
9859 is not required [conv.qual]. It would be normal to set this flag in
9860 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9861 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9862 This is the outermost level of a deduction, and PARM can be more CV
9863 qualified at this point.
9864 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9865 This is the outermost level of a deduction, and PARM can be less CV
9866 qualified at this point. */
9869 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9874 int strict_in = strict;
9876 /* I don't think this will do the right thing with respect to types.
9877 But the only case I've seen it in so far has been array bounds, where
9878 signedness is the only information lost, and I think that will be
9880 while (TREE_CODE (parm) == NOP_EXPR)
9881 parm = TREE_OPERAND (parm, 0);
9883 if (arg == error_mark_node)
9885 if (arg == unknown_type_node)
9886 /* We can't deduce anything from this, but we might get all the
9887 template args from other function args. */
9890 /* If PARM uses template parameters, then we can't bail out here,
9891 even if ARG == PARM, since we won't record unifications for the
9892 template parameters. We might need them if we're trying to
9893 figure out which of two things is more specialized. */
9894 if (arg == parm && !uses_template_parms (parm))
9897 /* Immediately reject some pairs that won't unify because of
9898 cv-qualification mismatches. */
9899 if (TREE_CODE (arg) == TREE_CODE (parm)
9901 /* It is the elements of the array which hold the cv quals of an array
9902 type, and the elements might be template type parms. We'll check
9904 && TREE_CODE (arg) != ARRAY_TYPE
9905 /* We check the cv-qualifiers when unifying with template type
9906 parameters below. We want to allow ARG `const T' to unify with
9907 PARM `T' for example, when computing which of two templates
9908 is more specialized, for example. */
9909 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9910 && !check_cv_quals_for_unify (strict_in, arg, parm))
9913 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9914 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9915 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9916 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9917 strict &= ~UNIFY_ALLOW_DERIVED;
9918 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9919 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9921 switch (TREE_CODE (parm))
9925 case UNBOUND_CLASS_TEMPLATE:
9926 /* In a type which contains a nested-name-specifier, template
9927 argument values cannot be deduced for template parameters used
9928 within the nested-name-specifier. */
9931 case TEMPLATE_TYPE_PARM:
9932 case TEMPLATE_TEMPLATE_PARM:
9933 case BOUND_TEMPLATE_TEMPLATE_PARM:
9934 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9936 if (TEMPLATE_TYPE_LEVEL (parm)
9937 != template_decl_level (tparm))
9938 /* The PARM is not one we're trying to unify. Just check
9939 to see if it matches ARG. */
9940 return (TREE_CODE (arg) == TREE_CODE (parm)
9941 && same_type_p (parm, arg)) ? 0 : 1;
9942 idx = TEMPLATE_TYPE_IDX (parm);
9943 targ = TREE_VEC_ELT (targs, idx);
9944 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9946 /* Check for mixed types and values. */
9947 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9948 && TREE_CODE (tparm) != TYPE_DECL)
9949 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9950 && TREE_CODE (tparm) != TEMPLATE_DECL))
9953 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9955 /* ARG must be constructed from a template class or a template
9956 template parameter. */
9957 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9958 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9962 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9963 tree parmvec = TYPE_TI_ARGS (parm);
9964 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9966 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9969 /* The parameter and argument roles have to be switched here
9970 in order to handle default arguments properly. For example,
9971 template<template <class> class TT> void f(TT<int>)
9972 should be able to accept vector<int> which comes from
9973 template <class T, class Allocator = allocator>
9976 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9980 /* Deduce arguments T, i from TT<T> or TT<i>.
9981 We check each element of PARMVEC and ARGVEC individually
9982 rather than the whole TREE_VEC since they can have
9983 different number of elements. */
9985 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
9987 if (unify (tparms, targs,
9988 TREE_VEC_ELT (parmvec, i),
9989 TREE_VEC_ELT (argvec, i),
9994 arg = TYPE_TI_TEMPLATE (arg);
9996 /* Fall through to deduce template name. */
9999 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10000 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10002 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
10004 /* Simple cases: Value already set, does match or doesn't. */
10005 if (targ != NULL_TREE && template_args_equal (targ, arg))
10012 /* If PARM is `const T' and ARG is only `int', we don't have
10013 a match unless we are allowing additional qualification.
10014 If ARG is `const int' and PARM is just `T' that's OK;
10015 that binds `const int' to `T'. */
10016 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10020 /* Consider the case where ARG is `const volatile int' and
10021 PARM is `const T'. Then, T should be `volatile int'. */
10022 arg = cp_build_qualified_type_real
10023 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10024 if (arg == error_mark_node)
10027 /* Simple cases: Value already set, does match or doesn't. */
10028 if (targ != NULL_TREE && same_type_p (targ, arg))
10033 /* Make sure that ARG is not a variable-sized array. (Note
10034 that were talking about variable-sized arrays (like
10035 `int[n]'), rather than arrays of unknown size (like
10036 `int[]').) We'll get very confused by such a type since
10037 the bound of the array will not be computable in an
10038 instantiation. Besides, such types are not allowed in
10039 ISO C++, so we can do as we please here. */
10040 if (variably_modified_type_p (arg, NULL_TREE))
10044 TREE_VEC_ELT (targs, idx) = arg;
10047 case TEMPLATE_PARM_INDEX:
10048 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10050 if (TEMPLATE_PARM_LEVEL (parm)
10051 != template_decl_level (tparm))
10052 /* The PARM is not one we're trying to unify. Just check
10053 to see if it matches ARG. */
10054 return !(TREE_CODE (arg) == TREE_CODE (parm)
10055 && cp_tree_equal (parm, arg));
10057 idx = TEMPLATE_PARM_IDX (parm);
10058 targ = TREE_VEC_ELT (targs, idx);
10061 return !cp_tree_equal (targ, arg);
10063 /* [temp.deduct.type] If, in the declaration of a function template
10064 with a non-type template-parameter, the non-type
10065 template-parameter is used in an expression in the function
10066 parameter-list and, if the corresponding template-argument is
10067 deduced, the template-argument type shall match the type of the
10068 template-parameter exactly, except that a template-argument
10069 deduced from an array bound may be of any integral type.
10070 The non-type parameter might use already deduced type parameters. */
10071 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10072 if (!TREE_TYPE (arg))
10073 /* Template-parameter dependent expression. Just accept it for now.
10074 It will later be processed in convert_template_argument. */
10076 else if (same_type_p (TREE_TYPE (arg), tparm))
10078 else if ((strict & UNIFY_ALLOW_INTEGER)
10079 && (TREE_CODE (tparm) == INTEGER_TYPE
10080 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10081 /* Convert the ARG to the type of PARM; the deduced non-type
10082 template argument must exactly match the types of the
10083 corresponding parameter. */
10084 arg = fold (build_nop (TREE_TYPE (parm), arg));
10085 else if (uses_template_parms (tparm))
10086 /* We haven't deduced the type of this parameter yet. Try again
10092 TREE_VEC_ELT (targs, idx) = arg;
10097 /* A pointer-to-member constant can be unified only with
10098 another constant. */
10099 if (TREE_CODE (arg) != PTRMEM_CST)
10102 /* Just unify the class member. It would be useless (and possibly
10103 wrong, depending on the strict flags) to unify also
10104 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10105 arg refer to the same variable, even if through different
10106 classes. For instance:
10108 struct A { int x; };
10111 Unification of &A::x and &B::x must succeed. */
10112 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10113 PTRMEM_CST_MEMBER (arg), strict);
10118 if (TREE_CODE (arg) != POINTER_TYPE)
10121 /* [temp.deduct.call]
10123 A can be another pointer or pointer to member type that can
10124 be converted to the deduced A via a qualification
10125 conversion (_conv.qual_).
10127 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10128 This will allow for additional cv-qualification of the
10129 pointed-to types if appropriate. */
10131 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10132 /* The derived-to-base conversion only persists through one
10133 level of pointers. */
10134 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10136 return unify (tparms, targs, TREE_TYPE (parm),
10137 TREE_TYPE (arg), strict);
10140 case REFERENCE_TYPE:
10141 if (TREE_CODE (arg) != REFERENCE_TYPE)
10143 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10144 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10147 if (TREE_CODE (arg) != ARRAY_TYPE)
10149 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10150 != (TYPE_DOMAIN (arg) == NULL_TREE))
10152 if (TYPE_DOMAIN (parm) != NULL_TREE)
10157 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10158 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10160 /* Our representation of array types uses "N - 1" as the
10161 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10162 not an integer constant. */
10163 if (TREE_CODE (parm_max) == MINUS_EXPR)
10165 arg_max = fold_build2 (PLUS_EXPR,
10168 TREE_OPERAND (parm_max, 1));
10169 parm_max = TREE_OPERAND (parm_max, 0);
10172 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10175 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10176 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10183 case ENUMERAL_TYPE:
10185 if (TREE_CODE (arg) != TREE_CODE (parm))
10188 /* We have already checked cv-qualification at the top of the
10190 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10193 /* As far as unification is concerned, this wins. Later checks
10194 will invalidate it if necessary. */
10197 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10198 /* Type INTEGER_CST can come from ordinary constant template args. */
10200 while (TREE_CODE (arg) == NOP_EXPR)
10201 arg = TREE_OPERAND (arg, 0);
10203 if (TREE_CODE (arg) != INTEGER_CST)
10205 return !tree_int_cst_equal (parm, arg);
10210 if (TREE_CODE (arg) != TREE_VEC)
10212 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10214 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10215 if (unify (tparms, targs,
10216 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10224 if (TREE_CODE (arg) != TREE_CODE (parm))
10227 if (TYPE_PTRMEMFUNC_P (parm))
10229 if (!TYPE_PTRMEMFUNC_P (arg))
10232 return unify (tparms, targs,
10233 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10234 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10238 if (CLASSTYPE_TEMPLATE_INFO (parm))
10240 tree t = NULL_TREE;
10242 if (strict_in & UNIFY_ALLOW_DERIVED)
10244 /* First, we try to unify the PARM and ARG directly. */
10245 t = try_class_unification (tparms, targs,
10250 /* Fallback to the special case allowed in
10251 [temp.deduct.call]:
10253 If P is a class, and P has the form
10254 template-id, then A can be a derived class of
10255 the deduced A. Likewise, if P is a pointer to
10256 a class of the form template-id, A can be a
10257 pointer to a derived class pointed to by the
10259 t = get_template_base (tparms, targs, parm, arg);
10265 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10266 && (CLASSTYPE_TI_TEMPLATE (parm)
10267 == CLASSTYPE_TI_TEMPLATE (arg)))
10268 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10269 Then, we should unify `int' and `U'. */
10272 /* There's no chance of unification succeeding. */
10275 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10276 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10278 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10283 case FUNCTION_TYPE:
10284 if (TREE_CODE (arg) != TREE_CODE (parm))
10287 if (unify (tparms, targs, TREE_TYPE (parm),
10288 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10290 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10291 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
10292 TREE_CODE (parm) == METHOD_TYPE);
10295 /* Unify a pointer to member with a pointer to member function, which
10296 deduces the type of the member as a function type. */
10297 if (TYPE_PTRMEMFUNC_P (arg))
10301 cp_cv_quals cv_quals;
10303 /* Check top-level cv qualifiers */
10304 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
10307 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10308 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
10311 /* Determine the type of the function we are unifying against. */
10312 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
10314 build_function_type (TREE_TYPE (method_type),
10315 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
10317 /* Extract the cv-qualifiers of the member function from the
10318 implicit object parameter and place them on the function
10319 type to be restored later. */
10321 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
10322 fntype = build_qualified_type (fntype, cv_quals);
10323 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
10326 if (TREE_CODE (arg) != OFFSET_TYPE)
10328 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10329 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10331 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10335 if (DECL_TEMPLATE_PARM_P (parm))
10336 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10337 if (arg != integral_constant_value (parm))
10342 case TEMPLATE_DECL:
10343 /* Matched cases are handled by the ARG == PARM test above. */
10347 gcc_assert (EXPR_P (parm));
10349 /* We must be looking at an expression. This can happen with
10353 void foo(S<I>, S<I + 2>);
10355 This is a "nondeduced context":
10359 The nondeduced contexts are:
10361 --A type that is a template-id in which one or more of
10362 the template-arguments is an expression that references
10363 a template-parameter.
10365 In these cases, we assume deduction succeeded, but don't
10366 actually infer any unifications. */
10368 if (!uses_template_parms (parm)
10369 && !template_args_equal (parm, arg))
10376 /* Note that DECL can be defined in this translation unit, if
10380 mark_definable (tree decl)
10383 DECL_NOT_REALLY_EXTERN (decl) = 1;
10384 FOR_EACH_CLONE (clone, decl)
10385 DECL_NOT_REALLY_EXTERN (clone) = 1;
10388 /* Called if RESULT is explicitly instantiated, or is a member of an
10389 explicitly instantiated class. */
10392 mark_decl_instantiated (tree result, int extern_p)
10394 SET_DECL_EXPLICIT_INSTANTIATION (result);
10396 /* If this entity has already been written out, it's too late to
10397 make any modifications. */
10398 if (TREE_ASM_WRITTEN (result))
10401 if (TREE_CODE (result) != FUNCTION_DECL)
10402 /* The TREE_PUBLIC flag for function declarations will have been
10403 set correctly by tsubst. */
10404 TREE_PUBLIC (result) = 1;
10406 /* This might have been set by an earlier implicit instantiation. */
10407 DECL_COMDAT (result) = 0;
10410 DECL_NOT_REALLY_EXTERN (result) = 0;
10413 mark_definable (result);
10414 /* Always make artificials weak. */
10415 if (DECL_ARTIFICIAL (result) && flag_weak)
10416 comdat_linkage (result);
10417 /* For WIN32 we also want to put explicit instantiations in
10418 linkonce sections. */
10419 else if (TREE_PUBLIC (result))
10420 maybe_make_one_only (result);
10423 /* If EXTERN_P, then this function will not be emitted -- unless
10424 followed by an explicit instantiation, at which point its linkage
10425 will be adjusted. If !EXTERN_P, then this function will be
10426 emitted here. In neither circumstance do we want
10427 import_export_decl to adjust the linkage. */
10428 DECL_INTERFACE_KNOWN (result) = 1;
10431 /* Given two function templates PAT1 and PAT2, return:
10433 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10434 -1 if PAT2 is more specialized than PAT1.
10435 0 if neither is more specialized.
10437 LEN indicates the number of parameters we should consider
10438 (defaulted parameters should not be considered).
10440 The 1998 std underspecified function template partial ordering, and
10441 DR214 addresses the issue. We take pairs of arguments, one from
10442 each of the templates, and deduce them against each other. One of
10443 the templates will be more specialized if all the *other*
10444 template's arguments deduce against its arguments and at least one
10445 of its arguments *does* *not* deduce against the other template's
10446 corresponding argument. Deduction is done as for class templates.
10447 The arguments used in deduction have reference and top level cv
10448 qualifiers removed. Iff both arguments were originally reference
10449 types *and* deduction succeeds in both directions, the template
10450 with the more cv-qualified argument wins for that pairing (if
10451 neither is more cv-qualified, they both are equal). Unlike regular
10452 deduction, after all the arguments have been deduced in this way,
10453 we do *not* verify the deduced template argument values can be
10454 substituted into non-deduced contexts, nor do we have to verify
10455 that all template arguments have been deduced. */
10458 more_specialized_fn (tree pat1, tree pat2, int len)
10460 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
10461 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
10462 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
10463 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
10464 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
10465 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
10466 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
10467 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
10471 /* If only one is a member function, they are unordered. */
10472 if (DECL_FUNCTION_MEMBER_P (decl1) != DECL_FUNCTION_MEMBER_P (decl2))
10475 /* Don't consider 'this' parameter. */
10476 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
10477 args1 = TREE_CHAIN (args1);
10478 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
10479 args2 = TREE_CHAIN (args2);
10481 /* If only one is a conversion operator, they are unordered. */
10482 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
10485 /* Consider the return type for a conversion function */
10486 if (DECL_CONV_FN_P (decl1))
10488 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
10489 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
10493 processing_template_decl++;
10497 tree arg1 = TREE_VALUE (args1);
10498 tree arg2 = TREE_VALUE (args2);
10499 int deduce1, deduce2;
10503 if (TREE_CODE (arg1) == REFERENCE_TYPE)
10505 arg1 = TREE_TYPE (arg1);
10506 quals1 = cp_type_quals (arg1);
10509 if (TREE_CODE (arg2) == REFERENCE_TYPE)
10511 arg2 = TREE_TYPE (arg2);
10512 quals2 = cp_type_quals (arg2);
10515 if ((quals1 < 0) != (quals2 < 0))
10517 /* Only of the args is a reference, see if we should apply
10518 array/function pointer decay to it. This is not part of
10519 DR214, but is, IMHO, consistent with the deduction rules
10520 for the function call itself, and with our earlier
10521 implementation of the underspecified partial ordering
10522 rules. (nathan). */
10525 switch (TREE_CODE (arg1))
10528 arg1 = TREE_TYPE (arg1);
10530 case FUNCTION_TYPE:
10531 arg1 = build_pointer_type (arg1);
10540 switch (TREE_CODE (arg2))
10543 arg2 = TREE_TYPE (arg2);
10545 case FUNCTION_TYPE:
10546 arg2 = build_pointer_type (arg2);
10555 arg1 = TYPE_MAIN_VARIANT (arg1);
10556 arg2 = TYPE_MAIN_VARIANT (arg2);
10558 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
10559 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
10565 if (better1 < 0 && better2 < 0)
10566 /* We've failed to deduce something in either direction.
10567 These must be unordered. */
10570 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
10572 /* Deduces in both directions, see if quals can
10573 disambiguate. Pretend the worse one failed to deduce. */
10574 if ((quals1 & quals2) == quals2)
10576 if ((quals1 & quals2) == quals1)
10579 if (deduce1 && !deduce2 && !better2)
10581 if (deduce2 && !deduce1 && !better1)
10584 args1 = TREE_CHAIN (args1);
10585 args2 = TREE_CHAIN (args2);
10588 processing_template_decl--;
10590 return (better1 > 0) - (better2 > 0);
10593 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10595 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10596 -1 if PAT2 is more specialized than PAT1.
10597 0 if neither is more specialized.
10599 FULL_ARGS is the full set of template arguments that triggers this
10600 partial ordering. */
10603 more_specialized_class (tree pat1, tree pat2, tree full_args)
10608 /* Just like what happens for functions, if we are ordering between
10609 different class template specializations, we may encounter dependent
10610 types in the arguments, and we need our dependency check functions
10611 to behave correctly. */
10612 ++processing_template_decl;
10613 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10614 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10618 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10619 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10622 --processing_template_decl;
10627 /* Return the template arguments that will produce the function signature
10628 DECL from the function template FN, with the explicit template
10629 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
10630 also match. Return NULL_TREE if no satisfactory arguments could be
10634 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
10636 int ntparms = DECL_NTPARMS (fn);
10637 tree targs = make_tree_vec (ntparms);
10639 tree decl_arg_types;
10641 /* Substitute the explicit template arguments into the type of DECL.
10642 The call to fn_type_unification will handle substitution into the
10644 decl_type = TREE_TYPE (decl);
10645 if (explicit_args && uses_template_parms (decl_type))
10648 tree converted_args;
10650 if (DECL_TEMPLATE_INFO (decl))
10651 tmpl = DECL_TI_TEMPLATE (decl);
10653 /* We can get here for some invalid specializations. */
10657 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10658 explicit_args, NULL_TREE,
10659 tf_none, /*require_all_arguments=*/0));
10660 if (converted_args == error_mark_node)
10663 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10664 if (decl_type == error_mark_node)
10668 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10669 /* Never do unification on the 'this' parameter. */
10670 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10671 decl_arg_types = TREE_CHAIN (decl_arg_types);
10673 if (fn_type_unification (fn, explicit_args, targs,
10675 (check_rettype || DECL_CONV_FN_P (fn)
10676 ? TREE_TYPE (decl_type) : NULL_TREE),
10683 /* Return the innermost template arguments that, when applied to a
10684 template specialization whose innermost template parameters are
10685 TPARMS, and whose specialization arguments are PARMS, yield the
10688 For example, suppose we have:
10690 template <class T, class U> struct S {};
10691 template <class T> struct S<T*, int> {};
10693 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10694 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10695 int}. The resulting vector will be {double}, indicating that `T'
10696 is bound to `double'. */
10699 get_class_bindings (tree tparms, tree parms, tree args)
10701 int i, ntparms = TREE_VEC_LENGTH (tparms);
10702 tree vec = make_tree_vec (ntparms);
10704 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10708 for (i = 0; i < ntparms; ++i)
10709 if (! TREE_VEC_ELT (vec, i))
10712 if (verify_class_unification (vec, parms, args))
10718 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10719 Pick the most specialized template, and return the corresponding
10720 instantiation, or if there is no corresponding instantiation, the
10721 template itself. If there is no most specialized template,
10722 error_mark_node is returned. If there are no templates at all,
10723 NULL_TREE is returned. */
10726 most_specialized_instantiation (tree instantiations)
10730 if (!instantiations)
10733 ++processing_template_decl;
10735 champ = instantiations;
10736 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10740 if (get_bindings (TREE_VALUE (champ),
10741 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10742 NULL_TREE, /*check_ret=*/false))
10745 if (get_bindings (TREE_VALUE (fn),
10746 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10747 NULL_TREE, /*check_ret=*/false))
10753 /* Equally specialized, move to next function. If there
10754 is no next function, nothing's most specialized. */
10755 fn = TREE_CHAIN (fn);
10761 /* Now verify that champ is better than everything earlier in the
10762 instantiation list. */
10763 for (fn = instantiations; fn != champ; fn = TREE_CHAIN (fn))
10764 if (get_bindings (TREE_VALUE (champ),
10765 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10766 NULL_TREE, /*check_ret=*/false)
10767 || !get_bindings (TREE_VALUE (fn),
10768 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10769 NULL_TREE, /*check_ret=*/false))
10775 processing_template_decl--;
10778 return error_mark_node;
10780 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10783 /* Return the most specialized of the list of templates in FNS that can
10784 produce an instantiation matching DECL, given the explicit template
10785 arguments EXPLICIT_ARGS. */
10788 most_specialized (tree fns, tree decl, tree explicit_args)
10790 tree candidates = NULL_TREE;
10793 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10795 tree candidate = TREE_VALUE (fn);
10797 args = get_bindings (candidate, decl, explicit_args, /*check_ret=*/true);
10799 candidates = tree_cons (NULL_TREE, candidate, candidates);
10802 return most_specialized_instantiation (candidates);
10805 /* If DECL is a specialization of some template, return the most
10806 general such template. Otherwise, returns NULL_TREE.
10808 For example, given:
10810 template <class T> struct S { template <class U> void f(U); };
10812 if TMPL is `template <class U> void S<int>::f(U)' this will return
10813 the full template. This function will not trace past partial
10814 specializations, however. For example, given in addition:
10816 template <class T> struct S<T*> { template <class U> void f(U); };
10818 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10819 `template <class T> template <class U> S<T*>::f(U)'. */
10822 most_general_template (tree decl)
10824 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10825 an immediate specialization. */
10826 if (TREE_CODE (decl) == FUNCTION_DECL)
10828 if (DECL_TEMPLATE_INFO (decl)) {
10829 decl = DECL_TI_TEMPLATE (decl);
10831 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10832 template friend. */
10833 if (TREE_CODE (decl) != TEMPLATE_DECL)
10839 /* Look for more and more general templates. */
10840 while (DECL_TEMPLATE_INFO (decl))
10842 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10843 (See cp-tree.h for details.) */
10844 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10847 if (CLASS_TYPE_P (TREE_TYPE (decl))
10848 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10851 /* Stop if we run into an explicitly specialized class template. */
10852 if (!DECL_NAMESPACE_SCOPE_P (decl)
10853 && DECL_CONTEXT (decl)
10854 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10857 decl = DECL_TI_TEMPLATE (decl);
10863 /* Return the most specialized of the class template specializations
10864 of TMPL which can produce an instantiation matching ARGS, or
10865 error_mark_node if the choice is ambiguous. */
10868 most_specialized_class (tree tmpl, tree args)
10870 tree list = NULL_TREE;
10875 tmpl = most_general_template (tmpl);
10876 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10879 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10882 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10883 TREE_TYPE (list) = TREE_TYPE (t);
10892 t = TREE_CHAIN (t);
10893 for (; t; t = TREE_CHAIN (t))
10895 fate = more_specialized_class (champ, t, args);
10902 t = TREE_CHAIN (t);
10904 return error_mark_node;
10910 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10912 fate = more_specialized_class (champ, t, args);
10914 return error_mark_node;
10920 /* Explicitly instantiate DECL. */
10923 do_decl_instantiation (tree decl, tree storage)
10925 tree result = NULL_TREE;
10929 /* An error occurred, for which grokdeclarator has already issued
10930 an appropriate message. */
10932 else if (! DECL_LANG_SPECIFIC (decl))
10934 error ("explicit instantiation of non-template %q#D", decl);
10937 else if (TREE_CODE (decl) == VAR_DECL)
10939 /* There is an asymmetry here in the way VAR_DECLs and
10940 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10941 the latter, the DECL we get back will be marked as a
10942 template instantiation, and the appropriate
10943 DECL_TEMPLATE_INFO will be set up. This does not happen for
10944 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10945 should handle VAR_DECLs as it currently handles
10947 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10948 if (!result || TREE_CODE (result) != VAR_DECL)
10950 error ("no matching template for %qD found", decl);
10954 else if (TREE_CODE (decl) != FUNCTION_DECL)
10956 error ("explicit instantiation of %q#D", decl);
10962 /* Check for various error cases. Note that if the explicit
10963 instantiation is valid the RESULT will currently be marked as an
10964 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
10965 until we get here. */
10967 if (DECL_TEMPLATE_SPECIALIZATION (result))
10969 /* DR 259 [temp.spec].
10971 Both an explicit instantiation and a declaration of an explicit
10972 specialization shall not appear in a program unless the explicit
10973 instantiation follows a declaration of the explicit specialization.
10975 For a given set of template parameters, if an explicit
10976 instantiation of a template appears after a declaration of an
10977 explicit specialization for that template, the explicit
10978 instantiation has no effect. */
10981 else if (DECL_EXPLICIT_INSTANTIATION (result))
10985 No program shall explicitly instantiate any template more
10988 We check DECL_NOT_REALLY_EXTERN so as not to complain when
10989 the first instantiation was `extern' and the second is not,
10990 and EXTERN_P for the opposite case. */
10991 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
10992 pedwarn ("duplicate explicit instantiation of %q#D", result);
10993 /* If an "extern" explicit instantiation follows an ordinary
10994 explicit instantiation, the template is instantiated. */
10998 else if (!DECL_IMPLICIT_INSTANTIATION (result))
11000 error ("no matching template for %qD found", result);
11003 else if (!DECL_TEMPLATE_INFO (result))
11005 pedwarn ("explicit instantiation of non-template %q#D", result);
11009 if (storage == NULL_TREE)
11011 else if (storage == ridpointers[(int) RID_EXTERN])
11013 if (pedantic && !in_system_header)
11014 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
11019 error ("storage class %qD applied to template instantiation", storage);
11021 mark_decl_instantiated (result, extern_p);
11023 instantiate_decl (result, /*defer_ok=*/1,
11024 /*expl_inst_class_mem_p=*/false);
11028 mark_class_instantiated (tree t, int extern_p)
11030 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
11031 SET_CLASSTYPE_INTERFACE_KNOWN (t);
11032 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
11033 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
11036 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
11037 rest_of_type_compilation (t, 1);
11041 /* Called from do_type_instantiation through binding_table_foreach to
11042 do recursive instantiation for the type bound in ENTRY. */
11044 bt_instantiate_type_proc (binding_entry entry, void *data)
11046 tree storage = *(tree *) data;
11048 if (IS_AGGR_TYPE (entry->type)
11049 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
11050 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
11053 /* Called from do_type_instantiation to instantiate a member
11054 (a member function or a static member variable) of an
11055 explicitly instantiated class template. */
11057 instantiate_class_member (tree decl, int extern_p)
11059 mark_decl_instantiated (decl, extern_p);
11061 instantiate_decl (decl, /*defer_ok=*/1,
11062 /*expl_inst_class_mem_p=*/true);
11065 /* Perform an explicit instantiation of template class T. STORAGE, if
11066 non-null, is the RID for extern, inline or static. COMPLAIN is
11067 nonzero if this is called from the parser, zero if called recursively,
11068 since the standard is unclear (as detailed below). */
11071 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
11076 int previous_instantiation_extern_p = 0;
11078 if (TREE_CODE (t) == TYPE_DECL)
11081 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
11083 error ("explicit instantiation of non-template type %qT", t);
11089 if (!COMPLETE_TYPE_P (t))
11091 if (complain & tf_error)
11092 error ("explicit instantiation of %q#T before definition of template",
11097 if (storage != NULL_TREE)
11099 if (pedantic && !in_system_header)
11100 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
11103 if (storage == ridpointers[(int) RID_INLINE])
11105 else if (storage == ridpointers[(int) RID_EXTERN])
11107 else if (storage == ridpointers[(int) RID_STATIC])
11111 error ("storage class %qD applied to template instantiation",
11117 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
11119 /* DR 259 [temp.spec].
11121 Both an explicit instantiation and a declaration of an explicit
11122 specialization shall not appear in a program unless the explicit
11123 instantiation follows a declaration of the explicit specialization.
11125 For a given set of template parameters, if an explicit
11126 instantiation of a template appears after a declaration of an
11127 explicit specialization for that template, the explicit
11128 instantiation has no effect. */
11131 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
11135 No program shall explicitly instantiate any template more
11138 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
11139 instantiation was `extern'. If EXTERN_P then the second is.
11140 These cases are OK. */
11141 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11143 if (!previous_instantiation_extern_p && !extern_p
11144 && (complain & tf_error))
11145 pedwarn ("duplicate explicit instantiation of %q#T", t);
11147 /* If we've already instantiated the template, just return now. */
11148 if (!CLASSTYPE_INTERFACE_ONLY (t))
11152 mark_class_instantiated (t, extern_p);
11160 /* In contrast to implicit instantiation, where only the
11161 declarations, and not the definitions, of members are
11162 instantiated, we have here:
11166 The explicit instantiation of a class template specialization
11167 implies the instantiation of all of its members not
11168 previously explicitly specialized in the translation unit
11169 containing the explicit instantiation.
11171 Of course, we can't instantiate member template classes, since
11172 we don't have any arguments for them. Note that the standard
11173 is unclear on whether the instantiation of the members are
11174 *explicit* instantiations or not. However, the most natural
11175 interpretation is that it should be an explicit instantiation. */
11178 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11179 if (TREE_CODE (tmp) == FUNCTION_DECL
11180 && DECL_TEMPLATE_INSTANTIATION (tmp))
11181 instantiate_class_member (tmp, extern_p);
11183 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11184 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11185 instantiate_class_member (tmp, extern_p);
11187 if (CLASSTYPE_NESTED_UTDS (t))
11188 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11189 bt_instantiate_type_proc, &storage);
11193 /* Given a function DECL, which is a specialization of TMPL, modify
11194 DECL to be a re-instantiation of TMPL with the same template
11195 arguments. TMPL should be the template into which tsubst'ing
11196 should occur for DECL, not the most general template.
11198 One reason for doing this is a scenario like this:
11201 void f(const T&, int i);
11203 void g() { f(3, 7); }
11206 void f(const T& t, const int i) { }
11208 Note that when the template is first instantiated, with
11209 instantiate_template, the resulting DECL will have no name for the
11210 first parameter, and the wrong type for the second. So, when we go
11211 to instantiate the DECL, we regenerate it. */
11214 regenerate_decl_from_template (tree decl, tree tmpl)
11216 /* The arguments used to instantiate DECL, from the most general
11221 args = DECL_TI_ARGS (decl);
11222 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11224 /* Make sure that we can see identifiers, and compute access
11226 push_access_scope (decl);
11228 if (TREE_CODE (decl) == FUNCTION_DECL)
11236 args_depth = TMPL_ARGS_DEPTH (args);
11237 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11238 if (args_depth > parms_depth)
11239 args = get_innermost_template_args (args, parms_depth);
11241 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11242 args, tf_error, NULL_TREE);
11244 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11247 /* Merge parameter declarations. */
11248 decl_parm = skip_artificial_parms_for (decl,
11249 DECL_ARGUMENTS (decl));
11251 = skip_artificial_parms_for (code_pattern,
11252 DECL_ARGUMENTS (code_pattern));
11258 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11259 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11260 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11262 parm_type = type_decays_to (parm_type);
11263 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11264 TREE_TYPE (decl_parm) = parm_type;
11265 attributes = DECL_ATTRIBUTES (pattern_parm);
11266 if (DECL_ATTRIBUTES (decl_parm) != attributes)
11268 DECL_ATTRIBUTES (decl_parm) = attributes;
11269 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
11271 decl_parm = TREE_CHAIN (decl_parm);
11272 pattern_parm = TREE_CHAIN (pattern_parm);
11275 /* Merge additional specifiers from the CODE_PATTERN. */
11276 if (DECL_DECLARED_INLINE_P (code_pattern)
11277 && !DECL_DECLARED_INLINE_P (decl))
11278 DECL_DECLARED_INLINE_P (decl) = 1;
11279 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11280 DECL_INLINE (decl) = 1;
11282 else if (TREE_CODE (decl) == VAR_DECL)
11284 if (!DECL_INITIALIZED_IN_CLASS_P (decl)
11285 && DECL_INITIAL (code_pattern))
11286 DECL_INITIAL (decl) =
11287 tsubst_expr (DECL_INITIAL (code_pattern), args,
11288 tf_error, DECL_TI_TEMPLATE (decl));
11291 gcc_unreachable ();
11293 pop_access_scope (decl);
11296 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11297 substituted to get DECL. */
11300 template_for_substitution (tree decl)
11302 tree tmpl = DECL_TI_TEMPLATE (decl);
11304 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11305 for the instantiation. This is not always the most general
11306 template. Consider, for example:
11309 struct S { template <class U> void f();
11310 template <> void f<int>(); };
11312 and an instantiation of S<double>::f<int>. We want TD to be the
11313 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11314 while (/* An instantiation cannot have a definition, so we need a
11315 more general template. */
11316 DECL_TEMPLATE_INSTANTIATION (tmpl)
11317 /* We must also deal with friend templates. Given:
11319 template <class T> struct S {
11320 template <class U> friend void f() {};
11323 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11324 so far as the language is concerned, but that's still
11325 where we get the pattern for the instantiation from. On
11326 other hand, if the definition comes outside the class, say:
11328 template <class T> struct S {
11329 template <class U> friend void f();
11331 template <class U> friend void f() {}
11333 we don't need to look any further. That's what the check for
11334 DECL_INITIAL is for. */
11335 || (TREE_CODE (decl) == FUNCTION_DECL
11336 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11337 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11339 /* The present template, TD, should not be a definition. If it
11340 were a definition, we should be using it! Note that we
11341 cannot restructure the loop to just keep going until we find
11342 a template with a definition, since that might go too far if
11343 a specialization was declared, but not defined. */
11344 gcc_assert (TREE_CODE (decl) != VAR_DECL
11345 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11347 /* Fetch the more general template. */
11348 tmpl = DECL_TI_TEMPLATE (tmpl);
11354 /* Produce the definition of D, a _DECL generated from a template. If
11355 DEFER_OK is nonzero, then we don't have to actually do the
11356 instantiation now; we just have to do it sometime. Normally it is
11357 an error if this is an explicit instantiation but D is undefined.
11358 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
11359 explicitly instantiated class template. */
11362 instantiate_decl (tree d, int defer_ok,
11363 bool expl_inst_class_mem_p)
11365 tree tmpl = DECL_TI_TEMPLATE (d);
11372 int pattern_defined;
11374 location_t saved_loc = input_location;
11376 /* This function should only be used to instantiate templates for
11377 functions and static member variables. */
11378 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11379 || TREE_CODE (d) == VAR_DECL);
11381 /* Variables are never deferred; if instantiation is required, they
11382 are instantiated right away. That allows for better code in the
11383 case that an expression refers to the value of the variable --
11384 if the variable has a constant value the referring expression can
11385 take advantage of that fact. */
11386 if (TREE_CODE (d) == VAR_DECL)
11389 /* Don't instantiate cloned functions. Instead, instantiate the
11390 functions they cloned. */
11391 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11392 d = DECL_CLONED_FUNCTION (d);
11394 if (DECL_TEMPLATE_INSTANTIATED (d))
11395 /* D has already been instantiated. It might seem reasonable to
11396 check whether or not D is an explicit instantiation, and, if so,
11397 stop here. But when an explicit instantiation is deferred
11398 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11399 is set, even though we still need to do the instantiation. */
11402 /* If we already have a specialization of this declaration, then
11403 there's no reason to instantiate it. Note that
11404 retrieve_specialization gives us both instantiations and
11405 specializations, so we must explicitly check
11406 DECL_TEMPLATE_SPECIALIZATION. */
11407 gen_tmpl = most_general_template (tmpl);
11408 gen_args = DECL_TI_ARGS (d);
11409 spec = retrieve_specialization (gen_tmpl, gen_args,
11410 /*class_specializations_p=*/false);
11411 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11414 /* This needs to happen before any tsubsting. */
11415 if (! push_tinst_level (d))
11418 timevar_push (TV_PARSE);
11420 /* We may be in the middle of deferred access check. Disable it now. */
11421 push_deferring_access_checks (dk_no_deferred);
11423 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11424 for the instantiation. */
11425 td = template_for_substitution (d);
11426 code_pattern = DECL_TEMPLATE_RESULT (td);
11428 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11429 || DECL_TEMPLATE_SPECIALIZATION (td))
11430 /* In the case of a friend template whose definition is provided
11431 outside the class, we may have too many arguments. Drop the
11432 ones we don't need. The same is true for specializations. */
11433 args = get_innermost_template_args
11434 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11438 if (TREE_CODE (d) == FUNCTION_DECL)
11439 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11441 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11442 /* Unless an explicit instantiation directive has already determined
11443 the linkage of D, remember that a definition is available for
11445 if (pattern_defined
11446 && !DECL_INTERFACE_KNOWN (d)
11447 && !DECL_NOT_REALLY_EXTERN (d))
11448 mark_definable (d);
11450 input_location = DECL_SOURCE_LOCATION (d);
11452 /* If D is a member of an explicitly instantiated class template,
11453 and no definition is available, treat it like an implicit
11455 if (!pattern_defined && expl_inst_class_mem_p
11456 && DECL_EXPLICIT_INSTANTIATION (d))
11458 DECL_NOT_REALLY_EXTERN (d) = 0;
11459 DECL_INTERFACE_KNOWN (d) = 0;
11460 SET_DECL_IMPLICIT_INSTANTIATION (d);
11465 /* Recheck the substitutions to obtain any warning messages
11466 about ignoring cv qualifiers. */
11467 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11468 tree type = TREE_TYPE (gen);
11470 /* Make sure that we can see identifiers, and compute access
11471 correctly. D is already the target FUNCTION_DECL with the
11473 push_access_scope (d);
11475 if (TREE_CODE (gen) == FUNCTION_DECL)
11477 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11478 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11479 tf_error | tf_warning, d);
11480 /* Don't simply tsubst the function type, as that will give
11481 duplicate warnings about poor parameter qualifications.
11482 The function arguments are the same as the decl_arguments
11483 without the top level cv qualifiers. */
11484 type = TREE_TYPE (type);
11486 tsubst (type, gen_args, tf_error | tf_warning, d);
11488 pop_access_scope (d);
11491 /* We should have set up DECL_INITIAL in instantiate_class_template
11492 for in-class definitions of static data members. */
11493 gcc_assert (!(TREE_CODE (d) == VAR_DECL
11494 && DECL_INITIALIZED_IN_CLASS_P (d)
11495 && DECL_INITIAL (d) == NULL_TREE));
11497 /* Do not instantiate templates that we know will be defined
11499 if (DECL_INTERFACE_KNOWN (d)
11500 && DECL_REALLY_EXTERN (d)
11501 && ! (TREE_CODE (d) == FUNCTION_DECL
11502 && DECL_INLINE (d)))
11504 /* Defer all other templates, unless we have been explicitly
11505 forbidden from doing so. We restore the source position here
11506 because it's used by add_pending_template. */
11507 else if (! pattern_defined || defer_ok)
11509 input_location = saved_loc;
11511 if (at_eof && !pattern_defined
11512 && DECL_EXPLICIT_INSTANTIATION (d))
11515 The definition of a non-exported function template, a
11516 non-exported member function template, or a non-exported
11517 member function or static data member of a class template
11518 shall be present in every translation unit in which it is
11519 explicitly instantiated. */
11521 ("explicit instantiation of %qD but no definition available", d);
11523 add_pending_template (d);
11526 /* Tell the repository that D is available in this translation unit
11527 -- and see if it is supposed to be instantiated here. */
11528 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11530 /* In a PCH file, despite the fact that the repository hasn't
11531 requested instantiation in the PCH it is still possible that
11532 an instantiation will be required in a file that includes the
11535 add_pending_template (d);
11536 /* Instantiate inline functions so that the inliner can do its
11537 job, even though we'll not be emitting a copy of this
11539 if (!(TREE_CODE (d) == FUNCTION_DECL
11540 && flag_inline_trees
11541 && DECL_DECLARED_INLINE_P (d)))
11545 need_push = !cfun || !global_bindings_p ();
11547 push_to_top_level ();
11549 /* Mark D as instantiated so that recursive calls to
11550 instantiate_decl do not try to instantiate it again. */
11551 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11553 /* Regenerate the declaration in case the template has been modified
11554 by a subsequent redeclaration. */
11555 regenerate_decl_from_template (d, td);
11557 /* We already set the file and line above. Reset them now in case
11558 they changed as a result of calling regenerate_decl_from_template. */
11559 input_location = DECL_SOURCE_LOCATION (d);
11561 if (TREE_CODE (d) == VAR_DECL)
11563 /* Clear out DECL_RTL; whatever was there before may not be right
11564 since we've reset the type of the declaration. */
11565 SET_DECL_RTL (d, NULL_RTX);
11566 DECL_IN_AGGR_P (d) = 0;
11568 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11569 initializer. That function will defer actual emission until
11570 we have a chance to determine linkage. */
11571 DECL_EXTERNAL (d) = 0;
11573 /* Enter the scope of D so that access-checking works correctly. */
11574 push_nested_class (DECL_CONTEXT (d));
11576 (!DECL_INITIALIZED_IN_CLASS_P (d)
11577 ? DECL_INITIAL (d) : NULL_TREE),
11579 pop_nested_class ();
11581 else if (TREE_CODE (d) == FUNCTION_DECL)
11583 htab_t saved_local_specializations;
11588 /* Save away the current list, in case we are instantiating one
11589 template from within the body of another. */
11590 saved_local_specializations = local_specializations;
11592 /* Set up the list of local specializations. */
11593 local_specializations = htab_create (37,
11594 hash_local_specialization,
11595 eq_local_specializations,
11598 /* Set up context. */
11599 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11601 /* Create substitution entries for the parameters. */
11602 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11603 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11604 spec_parm = DECL_ARGUMENTS (d);
11605 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11607 register_local_specialization (spec_parm, tmpl_parm);
11608 spec_parm = skip_artificial_parms_for (d, spec_parm);
11609 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11613 register_local_specialization (spec_parm, tmpl_parm);
11614 tmpl_parm = TREE_CHAIN (tmpl_parm);
11615 spec_parm = TREE_CHAIN (spec_parm);
11617 gcc_assert (!spec_parm);
11619 /* Substitute into the body of the function. */
11620 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11621 tf_error | tf_warning, tmpl);
11623 /* We don't need the local specializations any more. */
11624 htab_delete (local_specializations);
11625 local_specializations = saved_local_specializations;
11627 /* Finish the function. */
11628 d = finish_function (0);
11629 expand_or_defer_fn (d);
11632 /* We're not deferring instantiation any more. */
11633 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11636 pop_from_top_level ();
11639 input_location = saved_loc;
11640 pop_deferring_access_checks ();
11641 pop_tinst_level ();
11643 timevar_pop (TV_PARSE);
11648 /* Run through the list of templates that we wish we could
11649 instantiate, and instantiate any we can. RETRIES is the
11650 number of times we retry pending template instantiation. */
11653 instantiate_pending_templates (int retries)
11656 tree last = NULL_TREE;
11658 location_t saved_loc = input_location;
11659 int saved_in_system_header = in_system_header;
11661 /* Instantiating templates may trigger vtable generation. This in turn
11662 may require further template instantiations. We place a limit here
11663 to avoid infinite loop. */
11664 if (pending_templates && retries >= max_tinst_depth)
11666 error ("template instantiation depth exceeds maximum of %d"
11667 " instantiating %q+D, possibly from virtual table generation"
11668 " (use -ftemplate-depth-NN to increase the maximum)",
11669 max_tinst_depth, TREE_VALUE (pending_templates));
11677 t = &pending_templates;
11680 tree instantiation = TREE_VALUE (*t);
11682 reopen_tinst_level (TREE_PURPOSE (*t));
11684 if (TYPE_P (instantiation))
11688 if (!COMPLETE_TYPE_P (instantiation))
11690 instantiate_class_template (instantiation);
11691 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11692 for (fn = TYPE_METHODS (instantiation);
11694 fn = TREE_CHAIN (fn))
11695 if (! DECL_ARTIFICIAL (fn))
11696 instantiate_decl (fn,
11698 /*expl_inst_class_mem_p=*/false);
11699 if (COMPLETE_TYPE_P (instantiation))
11703 if (COMPLETE_TYPE_P (instantiation))
11704 /* If INSTANTIATION has been instantiated, then we don't
11705 need to consider it again in the future. */
11706 *t = TREE_CHAIN (*t);
11710 t = &TREE_CHAIN (*t);
11715 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11716 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11719 = instantiate_decl (instantiation,
11721 /*expl_inst_class_mem_p=*/false);
11722 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11726 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11727 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11728 /* If INSTANTIATION has been instantiated, then we don't
11729 need to consider it again in the future. */
11730 *t = TREE_CHAIN (*t);
11734 t = &TREE_CHAIN (*t);
11738 current_tinst_level = NULL_TREE;
11740 last_pending_template = last;
11742 while (reconsider);
11744 input_location = saved_loc;
11745 in_system_header = saved_in_system_header;
11748 /* Substitute ARGVEC into T, which is a list of initializers for
11749 either base class or a non-static data member. The TREE_PURPOSEs
11750 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11751 instantiate_decl. */
11754 tsubst_initializer_list (tree t, tree argvec)
11756 tree inits = NULL_TREE;
11758 for (; t; t = TREE_CHAIN (t))
11763 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11765 decl = expand_member_init (decl);
11766 if (decl && !DECL_P (decl))
11767 in_base_initializer = 1;
11769 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11771 in_base_initializer = 0;
11775 init = build_tree_list (decl, init);
11776 TREE_CHAIN (init) = inits;
11783 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11786 set_current_access_from_decl (tree decl)
11788 if (TREE_PRIVATE (decl))
11789 current_access_specifier = access_private_node;
11790 else if (TREE_PROTECTED (decl))
11791 current_access_specifier = access_protected_node;
11793 current_access_specifier = access_public_node;
11796 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11797 is the instantiation (which should have been created with
11798 start_enum) and ARGS are the template arguments to use. */
11801 tsubst_enum (tree tag, tree newtag, tree args)
11805 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11810 decl = TREE_VALUE (e);
11811 /* Note that in a template enum, the TREE_VALUE is the
11812 CONST_DECL, not the corresponding INTEGER_CST. */
11813 value = tsubst_expr (DECL_INITIAL (decl),
11814 args, tf_error | tf_warning,
11817 /* Give this enumeration constant the correct access. */
11818 set_current_access_from_decl (decl);
11820 /* Actually build the enumerator itself. */
11821 build_enumerator (DECL_NAME (decl), value, newtag);
11824 finish_enum (newtag);
11825 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11826 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11829 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11830 its type -- but without substituting the innermost set of template
11831 arguments. So, innermost set of template parameters will appear in
11835 get_mostly_instantiated_function_type (tree decl)
11843 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11844 targs = DECL_TI_ARGS (decl);
11845 tparms = DECL_TEMPLATE_PARMS (tmpl);
11846 parm_depth = TMPL_PARMS_DEPTH (tparms);
11848 /* There should be as many levels of arguments as there are levels
11850 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11852 fn_type = TREE_TYPE (tmpl);
11854 if (parm_depth == 1)
11855 /* No substitution is necessary. */
11859 int i, save_access_control;
11862 /* Replace the innermost level of the TARGS with NULL_TREEs to
11863 let tsubst know not to substitute for those parameters. */
11864 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11865 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11866 SET_TMPL_ARGS_LEVEL (partial_args, i,
11867 TMPL_ARGS_LEVEL (targs, i));
11868 SET_TMPL_ARGS_LEVEL (partial_args,
11869 TMPL_ARGS_DEPTH (targs),
11870 make_tree_vec (DECL_NTPARMS (tmpl)));
11872 /* Disable access control as this function is used only during
11874 save_access_control = flag_access_control;
11875 flag_access_control = 0;
11877 ++processing_template_decl;
11878 /* Now, do the (partial) substitution to figure out the
11879 appropriate function type. */
11880 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11881 --processing_template_decl;
11883 /* Substitute into the template parameters to obtain the real
11884 innermost set of parameters. This step is important if the
11885 innermost set of template parameters contains value
11886 parameters whose types depend on outer template parameters. */
11887 TREE_VEC_LENGTH (partial_args)--;
11888 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11890 flag_access_control = save_access_control;
11896 /* Return truthvalue if we're processing a template different from
11897 the last one involved in diagnostics. */
11899 problematic_instantiation_changed (void)
11901 return last_template_error_tick != tinst_level_tick;
11904 /* Remember current template involved in diagnostics. */
11906 record_last_problematic_instantiation (void)
11908 last_template_error_tick = tinst_level_tick;
11912 current_instantiation (void)
11914 return current_tinst_level;
11917 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11918 type. Return zero for ok, nonzero for disallowed. Issue error and
11919 warning messages under control of COMPLAIN. */
11922 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11924 if (INTEGRAL_TYPE_P (type))
11926 else if (POINTER_TYPE_P (type))
11928 else if (TYPE_PTR_TO_MEMBER_P (type))
11930 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11932 else if (TREE_CODE (type) == TYPENAME_TYPE)
11935 if (complain & tf_error)
11936 error ("%q#T is not a valid type for a template constant parameter", type);
11940 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
11941 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
11944 dependent_type_p_r (tree type)
11950 A type is dependent if it is:
11952 -- a template parameter. Template template parameters are types
11953 for us (since TYPE_P holds true for them) so we handle
11955 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
11956 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
11958 /* -- a qualified-id with a nested-name-specifier which contains a
11959 class-name that names a dependent type or whose unqualified-id
11960 names a dependent type. */
11961 if (TREE_CODE (type) == TYPENAME_TYPE)
11963 /* -- a cv-qualified type where the cv-unqualified type is
11965 type = TYPE_MAIN_VARIANT (type);
11966 /* -- a compound type constructed from any dependent type. */
11967 if (TYPE_PTR_TO_MEMBER_P (type))
11968 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
11969 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
11971 else if (TREE_CODE (type) == POINTER_TYPE
11972 || TREE_CODE (type) == REFERENCE_TYPE)
11973 return dependent_type_p (TREE_TYPE (type));
11974 else if (TREE_CODE (type) == FUNCTION_TYPE
11975 || TREE_CODE (type) == METHOD_TYPE)
11979 if (dependent_type_p (TREE_TYPE (type)))
11981 for (arg_type = TYPE_ARG_TYPES (type);
11983 arg_type = TREE_CHAIN (arg_type))
11984 if (dependent_type_p (TREE_VALUE (arg_type)))
11988 /* -- an array type constructed from any dependent type or whose
11989 size is specified by a constant expression that is
11990 value-dependent. */
11991 if (TREE_CODE (type) == ARRAY_TYPE)
11993 if (TYPE_DOMAIN (type)
11994 && ((value_dependent_expression_p
11995 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
11996 || (type_dependent_expression_p
11997 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
11999 return dependent_type_p (TREE_TYPE (type));
12002 /* -- a template-id in which either the template name is a template
12004 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
12006 /* ... or any of the template arguments is a dependent type or
12007 an expression that is type-dependent or value-dependent. */
12008 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
12009 && (any_dependent_template_arguments_p
12010 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
12013 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
12014 expression is not type-dependent, then it should already been
12016 if (TREE_CODE (type) == TYPEOF_TYPE)
12019 /* The standard does not specifically mention types that are local
12020 to template functions or local classes, but they should be
12021 considered dependent too. For example:
12023 template <int I> void f() {
12028 The size of `E' cannot be known until the value of `I' has been
12029 determined. Therefore, `E' must be considered dependent. */
12030 scope = TYPE_CONTEXT (type);
12031 if (scope && TYPE_P (scope))
12032 return dependent_type_p (scope);
12033 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
12034 return type_dependent_expression_p (scope);
12036 /* Other types are non-dependent. */
12040 /* Returns TRUE if TYPE is dependent, in the sense of
12041 [temp.dep.type]. */
12044 dependent_type_p (tree type)
12046 /* If there are no template parameters in scope, then there can't be
12047 any dependent types. */
12048 if (!processing_template_decl)
12051 /* If the type is NULL, we have not computed a type for the entity
12052 in question; in that case, the type is dependent. */
12056 /* Erroneous types can be considered non-dependent. */
12057 if (type == error_mark_node)
12060 /* If we have not already computed the appropriate value for TYPE,
12062 if (!TYPE_DEPENDENT_P_VALID (type))
12064 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
12065 TYPE_DEPENDENT_P_VALID (type) = 1;
12068 return TYPE_DEPENDENT_P (type);
12071 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
12074 dependent_scope_ref_p (tree expression, bool criterion (tree))
12079 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
12081 if (!TYPE_P (TREE_OPERAND (expression, 0)))
12084 scope = TREE_OPERAND (expression, 0);
12085 name = TREE_OPERAND (expression, 1);
12089 An id-expression is type-dependent if it contains a
12090 nested-name-specifier that contains a class-name that names a
12092 /* The suggested resolution to Core Issue 2 implies that if the
12093 qualifying type is the current class, then we must peek
12096 && currently_open_class (scope)
12097 && !criterion (name))
12099 if (dependent_type_p (scope))
12105 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
12106 [temp.dep.constexpr] */
12109 value_dependent_expression_p (tree expression)
12111 if (!processing_template_decl)
12114 /* A name declared with a dependent type. */
12115 if (DECL_P (expression) && type_dependent_expression_p (expression))
12118 switch (TREE_CODE (expression))
12120 case IDENTIFIER_NODE:
12121 /* A name that has not been looked up -- must be dependent. */
12124 case TEMPLATE_PARM_INDEX:
12125 /* A non-type template parm. */
12129 /* A non-type template parm. */
12130 if (DECL_TEMPLATE_PARM_P (expression))
12135 /* A constant with integral or enumeration type and is initialized
12136 with an expression that is value-dependent. */
12137 if (DECL_INITIAL (expression)
12138 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
12139 && value_dependent_expression_p (DECL_INITIAL (expression)))
12143 case DYNAMIC_CAST_EXPR:
12144 case STATIC_CAST_EXPR:
12145 case CONST_CAST_EXPR:
12146 case REINTERPRET_CAST_EXPR:
12148 /* These expressions are value-dependent if the type to which
12149 the cast occurs is dependent or the expression being casted
12150 is value-dependent. */
12152 tree type = TREE_TYPE (expression);
12154 if (dependent_type_p (type))
12157 /* A functional cast has a list of operands. */
12158 expression = TREE_OPERAND (expression, 0);
12161 /* If there are no operands, it must be an expression such
12162 as "int()". This should not happen for aggregate types
12163 because it would form non-constant expressions. */
12164 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12169 if (TREE_CODE (expression) == TREE_LIST)
12171 for (; expression; expression = TREE_CHAIN (expression))
12172 if (value_dependent_expression_p (TREE_VALUE (expression)))
12177 return value_dependent_expression_p (expression);
12182 /* A `sizeof' expression is value-dependent if the operand is
12184 expression = TREE_OPERAND (expression, 0);
12185 if (TYPE_P (expression))
12186 return dependent_type_p (expression);
12187 return type_dependent_expression_p (expression);
12190 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12192 case COMPONENT_REF:
12193 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12194 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12197 /* A CALL_EXPR is value-dependent if any argument is
12198 value-dependent. Why do we have to handle CALL_EXPRs in this
12199 function at all? First, some function calls, those for which
12200 value_dependent_expression_p is true, man appear in constant
12201 expressions. Second, there appear to be bugs which result in
12202 other CALL_EXPRs reaching this point. */
12204 tree function = TREE_OPERAND (expression, 0);
12205 tree args = TREE_OPERAND (expression, 1);
12207 if (value_dependent_expression_p (function))
12213 if (TREE_CODE (args) == TREE_LIST)
12215 for (; args; args = TREE_CHAIN (args))
12216 if (value_dependent_expression_p (TREE_VALUE (args)))
12221 return value_dependent_expression_p (args);
12225 /* A constant expression is value-dependent if any subexpression is
12226 value-dependent. */
12227 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12229 case tcc_reference:
12231 return (value_dependent_expression_p
12232 (TREE_OPERAND (expression, 0)));
12234 case tcc_comparison:
12236 return ((value_dependent_expression_p
12237 (TREE_OPERAND (expression, 0)))
12238 || (value_dependent_expression_p
12239 (TREE_OPERAND (expression, 1))));
12241 case tcc_expression:
12244 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12245 /* In some cases, some of the operands may be missing.
12246 (For example, in the case of PREDECREMENT_EXPR, the
12247 amount to increment by may be missing.) That doesn't
12248 make the expression dependent. */
12249 if (TREE_OPERAND (expression, i)
12250 && (value_dependent_expression_p
12251 (TREE_OPERAND (expression, i))))
12261 /* The expression is not value-dependent. */
12265 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12266 [temp.dep.expr]. */
12269 type_dependent_expression_p (tree expression)
12271 if (!processing_template_decl)
12274 if (expression == error_mark_node)
12277 /* An unresolved name is always dependent. */
12278 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12281 /* Some expression forms are never type-dependent. */
12282 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12283 || TREE_CODE (expression) == SIZEOF_EXPR
12284 || TREE_CODE (expression) == ALIGNOF_EXPR
12285 || TREE_CODE (expression) == TYPEID_EXPR
12286 || TREE_CODE (expression) == DELETE_EXPR
12287 || TREE_CODE (expression) == VEC_DELETE_EXPR
12288 || TREE_CODE (expression) == THROW_EXPR)
12291 /* The types of these expressions depends only on the type to which
12292 the cast occurs. */
12293 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12294 || TREE_CODE (expression) == STATIC_CAST_EXPR
12295 || TREE_CODE (expression) == CONST_CAST_EXPR
12296 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12297 || TREE_CODE (expression) == CAST_EXPR)
12298 return dependent_type_p (TREE_TYPE (expression));
12300 /* The types of these expressions depends only on the type created
12301 by the expression. */
12302 if (TREE_CODE (expression) == NEW_EXPR
12303 || TREE_CODE (expression) == VEC_NEW_EXPR)
12305 /* For NEW_EXPR tree nodes created inside a template, either
12306 the object type itself or a TREE_LIST may appear as the
12308 tree type = TREE_OPERAND (expression, 1);
12309 if (TREE_CODE (type) == TREE_LIST)
12310 /* This is an array type. We need to check array dimensions
12312 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12313 || value_dependent_expression_p
12314 (TREE_OPERAND (TREE_VALUE (type), 1));
12316 return dependent_type_p (type);
12319 if (TREE_CODE (expression) == SCOPE_REF
12320 && dependent_scope_ref_p (expression,
12321 type_dependent_expression_p))
12324 if (TREE_CODE (expression) == FUNCTION_DECL
12325 && DECL_LANG_SPECIFIC (expression)
12326 && DECL_TEMPLATE_INFO (expression)
12327 && (any_dependent_template_arguments_p
12328 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12331 if (TREE_CODE (expression) == TEMPLATE_DECL
12332 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12335 if (TREE_TYPE (expression) == unknown_type_node)
12337 if (TREE_CODE (expression) == ADDR_EXPR)
12338 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12339 if (TREE_CODE (expression) == COMPONENT_REF
12340 || TREE_CODE (expression) == OFFSET_REF)
12342 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12344 expression = TREE_OPERAND (expression, 1);
12345 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12348 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12349 if (TREE_CODE (expression) == SCOPE_REF)
12352 if (TREE_CODE (expression) == BASELINK)
12353 expression = BASELINK_FUNCTIONS (expression);
12355 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12357 if (any_dependent_template_arguments_p
12358 (TREE_OPERAND (expression, 1)))
12360 expression = TREE_OPERAND (expression, 0);
12362 gcc_assert (TREE_CODE (expression) == OVERLOAD);
12366 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12368 expression = OVL_NEXT (expression);
12373 return (dependent_type_p (TREE_TYPE (expression)));
12376 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12377 contains a type-dependent expression. */
12380 any_type_dependent_arguments_p (tree args)
12384 tree arg = TREE_VALUE (args);
12386 if (type_dependent_expression_p (arg))
12388 args = TREE_CHAIN (args);
12393 /* Returns TRUE if the ARG (a template argument) is dependent. */
12396 dependent_template_arg_p (tree arg)
12398 if (!processing_template_decl)
12401 if (TREE_CODE (arg) == TEMPLATE_DECL
12402 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12403 return dependent_template_p (arg);
12404 else if (TYPE_P (arg))
12405 return dependent_type_p (arg);
12407 return (type_dependent_expression_p (arg)
12408 || value_dependent_expression_p (arg));
12411 /* Returns true if ARGS (a collection of template arguments) contains
12412 any dependent arguments. */
12415 any_dependent_template_arguments_p (tree args)
12423 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12425 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12426 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12427 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12434 /* Returns TRUE if the template TMPL is dependent. */
12437 dependent_template_p (tree tmpl)
12439 if (TREE_CODE (tmpl) == OVERLOAD)
12443 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12445 tmpl = OVL_CHAIN (tmpl);
12450 /* Template template parameters are dependent. */
12451 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12452 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12454 /* So are names that have not been looked up. */
12455 if (TREE_CODE (tmpl) == SCOPE_REF
12456 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12458 /* So are member templates of dependent classes. */
12459 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12460 return dependent_type_p (DECL_CONTEXT (tmpl));
12464 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12467 dependent_template_id_p (tree tmpl, tree args)
12469 return (dependent_template_p (tmpl)
12470 || any_dependent_template_arguments_p (args));
12473 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12474 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12475 can be found. Note that this function peers inside uninstantiated
12476 templates and therefore should be used only in extremely limited
12477 situations. ONLY_CURRENT_P restricts this peering to the currently
12478 open classes hierarchy (which is required when comparing types). */
12481 resolve_typename_type (tree type, bool only_current_p)
12489 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12491 scope = TYPE_CONTEXT (type);
12492 name = TYPE_IDENTIFIER (type);
12494 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12495 it first before we can figure out what NAME refers to. */
12496 if (TREE_CODE (scope) == TYPENAME_TYPE)
12497 scope = resolve_typename_type (scope, only_current_p);
12498 /* If we don't know what SCOPE refers to, then we cannot resolve the
12500 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12501 return error_mark_node;
12502 /* If the SCOPE is a template type parameter, we have no way of
12503 resolving the name. */
12504 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12506 /* If the SCOPE is not the current instantiation, there's no reason
12507 to look inside it. */
12508 if (only_current_p && !currently_open_class (scope))
12509 return error_mark_node;
12510 /* If SCOPE is a partial instantiation, it will not have a valid
12511 TYPE_FIELDS list, so use the original template. */
12512 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12513 /* Enter the SCOPE so that name lookup will be resolved as if we
12514 were in the class definition. In particular, SCOPE will no
12515 longer be considered a dependent type. */
12516 pushed_scope = push_scope (scope);
12517 /* Look up the declaration. */
12518 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12519 /* Obtain the set of qualifiers applied to the TYPE. */
12520 quals = cp_type_quals (type);
12521 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12522 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12524 type = error_mark_node;
12525 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12526 && TREE_CODE (decl) == TYPE_DECL)
12527 type = TREE_TYPE (decl);
12528 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12529 && DECL_CLASS_TEMPLATE_P (decl))
12533 /* Obtain the template and the arguments. */
12534 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12535 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12536 /* Instantiate the template. */
12537 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12538 /*entering_scope=*/0, tf_error | tf_user);
12541 type = error_mark_node;
12542 /* Qualify the resulting type. */
12543 if (type != error_mark_node && quals)
12544 type = cp_build_qualified_type (type, quals);
12545 /* Leave the SCOPE. */
12547 pop_scope (pushed_scope);
12552 /* EXPR is an expression which is not type-dependent. Return a proxy
12553 for EXPR that can be used to compute the types of larger
12554 expressions containing EXPR. */
12557 build_non_dependent_expr (tree expr)
12561 /* Preserve null pointer constants so that the type of things like
12562 "p == 0" where "p" is a pointer can be determined. */
12563 if (null_ptr_cst_p (expr))
12565 /* Preserve OVERLOADs; the functions must be available to resolve
12567 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12568 TREE_OPERAND (expr, 0) : expr);
12569 if (is_overloaded_fn (inner_expr)
12570 || TREE_CODE (inner_expr) == OFFSET_REF)
12572 /* There is no need to return a proxy for a variable. */
12573 if (TREE_CODE (expr) == VAR_DECL)
12575 /* Preserve string constants; conversions from string constants to
12576 "char *" are allowed, even though normally a "const char *"
12577 cannot be used to initialize a "char *". */
12578 if (TREE_CODE (expr) == STRING_CST)
12580 /* Preserve arithmetic constants, as an optimization -- there is no
12581 reason to create a new node. */
12582 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12584 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12585 There is at least one place where we want to know that a
12586 particular expression is a throw-expression: when checking a ?:
12587 expression, there are special rules if the second or third
12588 argument is a throw-expression. */
12589 if (TREE_CODE (expr) == THROW_EXPR)
12592 if (TREE_CODE (expr) == COND_EXPR)
12593 return build3 (COND_EXPR,
12595 TREE_OPERAND (expr, 0),
12596 (TREE_OPERAND (expr, 1)
12597 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12598 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12599 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12600 if (TREE_CODE (expr) == COMPOUND_EXPR
12601 && !COMPOUND_EXPR_OVERLOADED (expr))
12602 return build2 (COMPOUND_EXPR,
12604 TREE_OPERAND (expr, 0),
12605 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12607 /* Otherwise, build a NON_DEPENDENT_EXPR.
12609 REFERENCE_TYPEs are not stripped for expressions in templates
12610 because doing so would play havoc with mangling. Consider, for
12613 template <typename T> void f<T& g>() { g(); }
12615 In the body of "f", the expression for "g" will have
12616 REFERENCE_TYPE, even though the standard says that it should
12617 not. The reason is that we must preserve the syntactic form of
12618 the expression so that mangling (say) "f<g>" inside the body of
12619 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12621 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12624 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12625 Return a new TREE_LIST with the various arguments replaced with
12626 equivalent non-dependent expressions. */
12629 build_non_dependent_args (tree args)
12634 new_args = NULL_TREE;
12635 for (a = args; a; a = TREE_CHAIN (a))
12636 new_args = tree_cons (NULL_TREE,
12637 build_non_dependent_expr (TREE_VALUE (a)),
12639 return nreverse (new_args);
12642 #include "gt-cp-pt.h"