1 /* Handle parameterized types (templates) for GNU C++.
2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing.
5 Rewritten by Jason Merrill (jason@cygnus.com).
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, USA. */
24 /* Known bugs or deficiencies include:
26 all methods must be provided in header files; can't use a source
27 file that contains only the method templates and "just win". */
31 #include "coretypes.h"
35 #include "pointer-set.h"
39 #include "cp-objcp-common.h"
40 #include "tree-inline.h"
47 #include "tree-iterator.h"
49 /* The type of functions taking a tree, and some additional data, and
51 typedef int (*tree_fn_t) (tree, void*);
53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose
54 instantiations have been deferred, either because their definitions
55 were not yet available, or because we were putting off doing the work.
56 The TREE_PURPOSE of each entry is either a DECL (for a function or
57 static data member), or a TYPE (for a class) indicating what we are
58 hoping to instantiate. The TREE_VALUE is not used. */
59 static GTY(()) tree pending_templates;
60 static GTY(()) tree last_pending_template;
62 int processing_template_parmlist;
63 static int template_header_count;
65 static GTY(()) tree saved_trees;
66 static GTY(()) varray_type inline_parm_levels;
67 static size_t inline_parm_levels_used;
69 static GTY(()) tree current_tinst_level;
71 static GTY(()) tree saved_access_scope;
73 /* Live only within one (recursive) call to tsubst_expr. We use
74 this to pass the statement expression node from the STMT_EXPR
75 to the EXPR_STMT that is its result. */
76 static tree cur_stmt_expr;
78 /* A map from local variable declarations in the body of the template
79 presently being instantiated to the corresponding instantiated
81 static htab_t local_specializations;
83 #define UNIFY_ALLOW_NONE 0
84 #define UNIFY_ALLOW_MORE_CV_QUAL 1
85 #define UNIFY_ALLOW_LESS_CV_QUAL 2
86 #define UNIFY_ALLOW_DERIVED 4
87 #define UNIFY_ALLOW_INTEGER 8
88 #define UNIFY_ALLOW_OUTER_LEVEL 16
89 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32
90 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64
92 static void push_access_scope (tree);
93 static void pop_access_scope (tree);
94 static int resolve_overloaded_unification (tree, tree, tree, tree,
95 unification_kind_t, int);
96 static int try_one_overload (tree, tree, tree, tree, tree,
97 unification_kind_t, int, bool);
98 static int unify (tree, tree, tree, tree, int);
99 static void add_pending_template (tree);
100 static void reopen_tinst_level (tree);
101 static tree classtype_mangled_name (tree);
102 static char* mangle_class_name_for_template (const char *, tree, tree);
103 static tree tsubst_initializer_list (tree, tree);
104 static tree get_class_bindings (tree, tree, tree);
105 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, int);
106 static void tsubst_enum (tree, tree, tree);
107 static tree add_to_template_args (tree, tree);
108 static tree add_outermost_template_args (tree, tree);
109 static bool check_instantiated_args (tree, tree, tsubst_flags_t);
110 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*);
111 static int type_unification_real (tree, tree, tree, tree,
112 int, unification_kind_t, int);
113 static void note_template_header (int);
114 static tree convert_nontype_argument_function (tree, tree);
115 static tree convert_nontype_argument (tree, tree);
116 static tree convert_template_argument (tree, tree, tree,
117 tsubst_flags_t, int, tree);
118 static int for_each_template_parm (tree, tree_fn_t, void*,
119 struct pointer_set_t*);
120 static tree build_template_parm_index (int, int, int, tree, tree);
121 static int inline_needs_template_parms (tree);
122 static void push_inline_template_parms_recursive (tree, int);
123 static tree retrieve_local_specialization (tree);
124 static void register_local_specialization (tree, tree);
125 static tree reduce_template_parm_level (tree, tree, int);
126 static int mark_template_parm (tree, void *);
127 static int template_parm_this_level_p (tree, void *);
128 static tree tsubst_friend_function (tree, tree);
129 static tree tsubst_friend_class (tree, tree);
130 static int can_complete_type_without_circularity (tree);
131 static tree get_bindings (tree, tree, tree, bool);
132 static int template_decl_level (tree);
133 static int check_cv_quals_for_unify (int, tree, tree);
134 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree);
135 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree);
136 static tree tsubst_template_parms (tree, tree, tsubst_flags_t);
137 static void regenerate_decl_from_template (tree, tree);
138 static tree most_specialized (tree, tree, tree);
139 static tree most_specialized_class (tree, tree);
140 static int template_class_depth_real (tree, int);
141 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int);
142 static tree tsubst_arg_types (tree, tree, tsubst_flags_t, tree);
143 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree);
144 static void check_specialization_scope (void);
145 static tree process_partial_specialization (tree);
146 static void set_current_access_from_decl (tree);
147 static void check_default_tmpl_args (tree, tree, int, int);
148 static tree tsubst_call_declarator_parms (tree, tree, tsubst_flags_t, tree);
149 static tree get_template_base (tree, tree, tree, tree);
150 static int verify_class_unification (tree, tree, tree);
151 static tree try_class_unification (tree, tree, tree, tree);
152 static int coerce_template_template_parms (tree, tree, tsubst_flags_t,
154 static tree determine_specialization (tree, tree, tree *, int, int);
155 static int template_args_equal (tree, tree);
156 static void tsubst_default_arguments (tree);
157 static tree for_each_template_parm_r (tree *, int *, void *);
158 static tree copy_default_args_to_explicit_spec_1 (tree, tree);
159 static void copy_default_args_to_explicit_spec (tree);
160 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t);
161 static int eq_local_specializations (const void *, const void *);
162 static bool dependent_type_p_r (tree);
163 static tree tsubst (tree, tree, tsubst_flags_t, tree);
164 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree);
165 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree);
167 /* Make the current scope suitable for access checking when we are
168 processing T. T can be FUNCTION_DECL for instantiated function
169 template, or VAR_DECL for static member variable (need by
170 instantiate_decl). */
173 push_access_scope (tree t)
175 gcc_assert (TREE_CODE (t) == FUNCTION_DECL
176 || TREE_CODE (t) == VAR_DECL);
178 if (DECL_FRIEND_CONTEXT (t))
179 push_nested_class (DECL_FRIEND_CONTEXT (t));
180 else if (DECL_CLASS_SCOPE_P (t))
181 push_nested_class (DECL_CONTEXT (t));
183 push_to_top_level ();
185 if (TREE_CODE (t) == FUNCTION_DECL)
187 saved_access_scope = tree_cons
188 (NULL_TREE, current_function_decl, saved_access_scope);
189 current_function_decl = t;
193 /* Restore the scope set up by push_access_scope. T is the node we
197 pop_access_scope (tree t)
199 if (TREE_CODE (t) == FUNCTION_DECL)
201 current_function_decl = TREE_VALUE (saved_access_scope);
202 saved_access_scope = TREE_CHAIN (saved_access_scope);
205 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t))
208 pop_from_top_level ();
211 /* Do any processing required when DECL (a member template
212 declaration) is finished. Returns the TEMPLATE_DECL corresponding
213 to DECL, unless it is a specialization, in which case the DECL
214 itself is returned. */
217 finish_member_template_decl (tree decl)
219 if (decl == error_mark_node)
220 return error_mark_node;
222 gcc_assert (DECL_P (decl));
224 if (TREE_CODE (decl) == TYPE_DECL)
228 type = TREE_TYPE (decl);
229 if (IS_AGGR_TYPE (type)
230 && CLASSTYPE_TEMPLATE_INFO (type)
231 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
233 tree tmpl = CLASSTYPE_TI_TEMPLATE (type);
234 check_member_template (tmpl);
239 else if (TREE_CODE (decl) == FIELD_DECL)
240 error ("data member %qD cannot be a member template", decl);
241 else if (DECL_TEMPLATE_INFO (decl))
243 if (!DECL_TEMPLATE_SPECIALIZATION (decl))
245 check_member_template (DECL_TI_TEMPLATE (decl));
246 return DECL_TI_TEMPLATE (decl);
252 error ("invalid member template declaration %qD", decl);
254 return error_mark_node;
257 /* Returns the template nesting level of the indicated class TYPE.
267 A<T>::B<U> has depth two, while A<T> has depth one.
268 Both A<T>::B<int> and A<int>::B<U> have depth one, if
269 COUNT_SPECIALIZATIONS is 0 or if they are instantiations, not
272 This function is guaranteed to return 0 if passed NULL_TREE so
273 that, for example, `template_class_depth (current_class_type)' is
277 template_class_depth_real (tree type, int count_specializations)
282 type && TREE_CODE (type) != NAMESPACE_DECL;
283 type = (TREE_CODE (type) == FUNCTION_DECL)
284 ? CP_DECL_CONTEXT (type) : TYPE_CONTEXT (type))
286 if (TREE_CODE (type) != FUNCTION_DECL)
288 if (CLASSTYPE_TEMPLATE_INFO (type)
289 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
290 && ((count_specializations
291 && CLASSTYPE_TEMPLATE_SPECIALIZATION (type))
292 || uses_template_parms (CLASSTYPE_TI_ARGS (type))))
297 if (DECL_TEMPLATE_INFO (type)
298 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (type))
299 && ((count_specializations
300 && DECL_TEMPLATE_SPECIALIZATION (type))
301 || uses_template_parms (DECL_TI_ARGS (type))))
309 /* Returns the template nesting level of the indicated class TYPE.
310 Like template_class_depth_real, but instantiations do not count in
314 template_class_depth (tree type)
316 return template_class_depth_real (type, /*count_specializations=*/0);
319 /* Returns 1 if processing DECL as part of do_pending_inlines
320 needs us to push template parms. */
323 inline_needs_template_parms (tree decl)
325 if (! DECL_TEMPLATE_INFO (decl))
328 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl)))
329 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl)));
332 /* Subroutine of maybe_begin_member_template_processing.
333 Push the template parms in PARMS, starting from LEVELS steps into the
334 chain, and ending at the beginning, since template parms are listed
338 push_inline_template_parms_recursive (tree parmlist, int levels)
340 tree parms = TREE_VALUE (parmlist);
344 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1);
346 ++processing_template_decl;
347 current_template_parms
348 = tree_cons (size_int (processing_template_decl),
349 parms, current_template_parms);
350 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1;
352 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec,
354 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i)
356 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
357 gcc_assert (DECL_P (parm));
359 switch (TREE_CODE (parm))
368 /* Make a CONST_DECL as is done in process_template_parm.
369 It is ugly that we recreate this here; the original
370 version built in process_template_parm is no longer
372 tree decl = build_decl (CONST_DECL, DECL_NAME (parm),
374 DECL_ARTIFICIAL (decl) = 1;
375 TREE_CONSTANT (decl) = 1;
376 TREE_INVARIANT (decl) = 1;
377 TREE_READONLY (decl) = 1;
378 DECL_INITIAL (decl) = DECL_INITIAL (parm);
379 SET_DECL_TEMPLATE_PARM_P (decl);
390 /* Restore the template parameter context for a member template or
391 a friend template defined in a class definition. */
394 maybe_begin_member_template_processing (tree decl)
399 if (inline_needs_template_parms (decl))
401 parms = DECL_TEMPLATE_PARMS (most_general_template (decl));
402 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl;
404 if (DECL_TEMPLATE_SPECIALIZATION (decl))
407 parms = TREE_CHAIN (parms);
410 push_inline_template_parms_recursive (parms, levels);
413 /* Remember how many levels of template parameters we pushed so that
414 we can pop them later. */
415 if (!inline_parm_levels)
416 VARRAY_INT_INIT (inline_parm_levels, 4, "inline_parm_levels");
417 if (inline_parm_levels_used == inline_parm_levels->num_elements)
418 VARRAY_GROW (inline_parm_levels, 2 * inline_parm_levels_used);
419 VARRAY_INT (inline_parm_levels, inline_parm_levels_used) = levels;
420 ++inline_parm_levels_used;
423 /* Undo the effects of maybe_begin_member_template_processing. */
426 maybe_end_member_template_processing (void)
430 if (!inline_parm_levels_used)
433 --inline_parm_levels_used;
435 i < VARRAY_INT (inline_parm_levels, inline_parm_levels_used);
438 --processing_template_decl;
439 current_template_parms = TREE_CHAIN (current_template_parms);
444 /* Return a new template argument vector which contains all of ARGS,
445 but has as its innermost set of arguments the EXTRA_ARGS. */
448 add_to_template_args (tree args, tree extra_args)
455 extra_depth = TMPL_ARGS_DEPTH (extra_args);
456 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth);
458 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i)
459 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i));
461 for (j = 1; j <= extra_depth; ++j, ++i)
462 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j));
467 /* Like add_to_template_args, but only the outermost ARGS are added to
468 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH
469 (EXTRA_ARGS) levels are added. This function is used to combine
470 the template arguments from a partial instantiation with the
471 template arguments used to attain the full instantiation from the
472 partial instantiation. */
475 add_outermost_template_args (tree args, tree extra_args)
479 /* If there are more levels of EXTRA_ARGS than there are ARGS,
480 something very fishy is going on. */
481 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args));
483 /* If *all* the new arguments will be the EXTRA_ARGS, just return
485 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args))
488 /* For the moment, we make ARGS look like it contains fewer levels. */
489 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args);
491 new_args = add_to_template_args (args, extra_args);
493 /* Now, we restore ARGS to its full dimensions. */
494 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args);
499 /* Return the N levels of innermost template arguments from the ARGS. */
502 get_innermost_template_args (tree args, int n)
510 /* If N is 1, just return the innermost set of template arguments. */
512 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args));
514 /* If we're not removing anything, just return the arguments we were
516 extra_levels = TMPL_ARGS_DEPTH (args) - n;
517 gcc_assert (extra_levels >= 0);
518 if (extra_levels == 0)
521 /* Make a new set of arguments, not containing the outer arguments. */
522 new_args = make_tree_vec (n);
523 for (i = 1; i <= n; ++i)
524 SET_TMPL_ARGS_LEVEL (new_args, i,
525 TMPL_ARGS_LEVEL (args, i + extra_levels));
530 /* We've got a template header coming up; push to a new level for storing
534 begin_template_parm_list (void)
536 /* We use a non-tag-transparent scope here, which causes pushtag to
537 put tags in this scope, rather than in the enclosing class or
538 namespace scope. This is the right thing, since we want
539 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a
540 global template class, push_template_decl handles putting the
541 TEMPLATE_DECL into top-level scope. For a nested template class,
544 template <class T> struct S1 {
545 template <class T> struct S2 {};
548 pushtag contains special code to call pushdecl_with_scope on the
549 TEMPLATE_DECL for S2. */
550 begin_scope (sk_template_parms, NULL);
551 ++processing_template_decl;
552 ++processing_template_parmlist;
553 note_template_header (0);
556 /* This routine is called when a specialization is declared. If it is
557 invalid to declare a specialization here, an error is reported. */
560 check_specialization_scope (void)
562 tree scope = current_scope ();
566 An explicit specialization shall be declared in the namespace of
567 which the template is a member, or, for member templates, in the
568 namespace of which the enclosing class or enclosing class
569 template is a member. An explicit specialization of a member
570 function, member class or static data member of a class template
571 shall be declared in the namespace of which the class template
573 if (scope && TREE_CODE (scope) != NAMESPACE_DECL)
574 error ("explicit specialization in non-namespace scope %qD", scope);
578 In an explicit specialization declaration for a member of a class
579 template or a member template that appears in namespace scope,
580 the member template and some of its enclosing class templates may
581 remain unspecialized, except that the declaration shall not
582 explicitly specialize a class member template if its enclosing
583 class templates are not explicitly specialized as well. */
584 if (current_template_parms)
585 error ("enclosing class templates are not explicitly specialized");
588 /* We've just seen template <>. */
591 begin_specialization (void)
593 begin_scope (sk_template_spec, NULL);
594 note_template_header (1);
595 check_specialization_scope ();
598 /* Called at then end of processing a declaration preceded by
602 end_specialization (void)
605 reset_specialization ();
608 /* Any template <>'s that we have seen thus far are not referring to a
609 function specialization. */
612 reset_specialization (void)
614 processing_specialization = 0;
615 template_header_count = 0;
618 /* We've just seen a template header. If SPECIALIZATION is nonzero,
619 it was of the form template <>. */
622 note_template_header (int specialization)
624 processing_specialization = specialization;
625 template_header_count++;
628 /* We're beginning an explicit instantiation. */
631 begin_explicit_instantiation (void)
633 gcc_assert (!processing_explicit_instantiation);
634 processing_explicit_instantiation = true;
639 end_explicit_instantiation (void)
641 gcc_assert (processing_explicit_instantiation);
642 processing_explicit_instantiation = false;
645 /* An explicit specialization or partial specialization TMPL is being
646 declared. Check that the namespace in which the specialization is
647 occurring is permissible. Returns false iff it is invalid to
648 specialize TMPL in the current namespace. */
651 check_specialization_namespace (tree tmpl)
653 tree tpl_ns = decl_namespace_context (tmpl);
657 An explicit specialization shall be declared in the namespace of
658 which the template is a member, or, for member templates, in the
659 namespace of which the enclosing class or enclosing class
660 template is a member. An explicit specialization of a member
661 function, member class or static data member of a class template
662 shall be declared in the namespace of which the class template is
664 if (is_associated_namespace (current_namespace, tpl_ns))
665 /* Same or super-using namespace. */
669 pedwarn ("specialization of %qD in different namespace", tmpl);
670 pedwarn (" from definition of %q+#D", tmpl);
675 /* SPEC is an explicit instantiation. Check that it is valid to
676 perform this explicit instantiation in the current namespace. */
679 check_explicit_instantiation_namespace (tree spec)
683 /* DR 275: An explicit instantiation shall appear in an enclosing
684 namespace of its template. */
685 ns = decl_namespace_context (spec);
686 if (!is_ancestor (current_namespace, ns))
687 pedwarn ("explicit instantiation of %qD in namespace %qD "
688 "(which does not enclose namespace %qD)",
689 spec, current_namespace, ns);
692 /* The TYPE is being declared. If it is a template type, that means it
693 is a partial specialization. Do appropriate error-checking. */
696 maybe_process_partial_specialization (tree type)
698 /* TYPE maybe an ERROR_MARK_NODE. */
699 tree context = TYPE_P (type) ? TYPE_CONTEXT (type) : NULL_TREE;
701 if (CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type))
703 /* This is for ordinary explicit specialization and partial
704 specialization of a template class such as:
706 template <> class C<int>;
710 template <class T> class C<T*>;
712 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */
714 if (CLASSTYPE_IMPLICIT_INSTANTIATION (type)
715 && !COMPLETE_TYPE_P (type))
717 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type));
718 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
719 if (processing_template_decl)
720 push_template_decl (TYPE_MAIN_DECL (type));
722 else if (CLASSTYPE_TEMPLATE_INSTANTIATION (type))
723 error ("specialization of %qT after instantiation", type);
725 else if (CLASS_TYPE_P (type)
726 && !CLASSTYPE_USE_TEMPLATE (type)
727 && CLASSTYPE_TEMPLATE_INFO (type)
728 && context && CLASS_TYPE_P (context)
729 && CLASSTYPE_TEMPLATE_INFO (context))
731 /* This is for an explicit specialization of member class
732 template according to [temp.expl.spec/18]:
734 template <> template <class U> class C<int>::D;
736 The context `C<int>' must be an implicit instantiation.
737 Otherwise this is just a member class template declared
740 template <> class C<int> { template <class U> class D; };
741 template <> template <class U> class C<int>::D;
743 In the first case, `C<int>::D' is a specialization of `C<T>::D'
744 while in the second case, `C<int>::D' is a primary template
745 and `C<T>::D' may not exist. */
747 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context)
748 && !COMPLETE_TYPE_P (type))
752 if (current_namespace
753 != decl_namespace_context (CLASSTYPE_TI_TEMPLATE (type)))
755 pedwarn ("specializing %q#T in different namespace", type);
756 pedwarn (" from definition of %q+#D",
757 CLASSTYPE_TI_TEMPLATE (type));
760 /* Check for invalid specialization after instantiation:
762 template <> template <> class C<int>::D<int>;
763 template <> template <class U> class C<int>::D; */
765 for (t = DECL_TEMPLATE_INSTANTIATIONS
766 (most_general_template (CLASSTYPE_TI_TEMPLATE (type)));
767 t; t = TREE_CHAIN (t))
768 if (TREE_VALUE (t) != type
769 && TYPE_CONTEXT (TREE_VALUE (t)) == context)
770 error ("specialization %qT after instantiation %qT",
771 type, TREE_VALUE (t));
773 /* Mark TYPE as a specialization. And as a result, we only
774 have one level of template argument for the innermost
776 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type);
777 CLASSTYPE_TI_ARGS (type)
778 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type));
781 else if (processing_specialization)
782 error ("explicit specialization of non-template %qT", type);
785 /* Returns nonzero if we can optimize the retrieval of specializations
786 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we
787 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */
790 optimize_specialization_lookup_p (tree tmpl)
792 return (DECL_FUNCTION_TEMPLATE_P (tmpl)
793 && DECL_CLASS_SCOPE_P (tmpl)
794 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template
796 && CLASS_TYPE_P (DECL_CONTEXT (tmpl))
797 /* The optimized lookup depends on the fact that the
798 template arguments for the member function template apply
799 purely to the containing class, which is not true if the
800 containing class is an explicit or partial
802 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl))
803 && !DECL_MEMBER_TEMPLATE_P (tmpl)
804 && !DECL_CONV_FN_P (tmpl)
805 /* It is possible to have a template that is not a member
806 template and is not a member of a template class:
808 template <typename T>
809 struct S { friend A::f(); };
811 Here, the friend function is a template, but the context does
812 not have template information. The optimized lookup relies
813 on having ARGS be the template arguments for both the class
814 and the function template. */
815 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl)));
818 /* Retrieve the specialization (in the sense of [temp.spec] - a
819 specialization is either an instantiation or an explicit
820 specialization) of TMPL for the given template ARGS. If there is
821 no such specialization, return NULL_TREE. The ARGS are a vector of
822 arguments, or a vector of vectors of arguments, in the case of
823 templates with more than one level of parameters.
825 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true,
826 then we search for a partial specialization matching ARGS. This
827 parameter is ignored if TMPL is not a class template. */
830 retrieve_specialization (tree tmpl, tree args,
831 bool class_specializations_p)
833 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
835 /* There should be as many levels of arguments as there are
836 levels of parameters. */
837 gcc_assert (TMPL_ARGS_DEPTH (args)
838 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)));
840 if (optimize_specialization_lookup_p (tmpl))
843 tree class_specialization;
844 VEC(tree,gc) *methods;
848 /* The template arguments actually apply to the containing
849 class. Find the class specialization with those
851 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl));
853 = retrieve_specialization (class_template, args,
854 /*class_specializations_p=*/false);
855 if (!class_specialization)
857 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC
858 for the specialization. */
859 idx = class_method_index_for_fn (class_specialization, tmpl);
862 /* Iterate through the methods with the indicated name, looking
863 for the one that has an instance of TMPL. */
864 methods = CLASSTYPE_METHOD_VEC (class_specialization);
865 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns))
867 tree fn = OVL_CURRENT (fns);
868 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl)
878 /* Class templates store their instantiations on the
879 DECL_TEMPLATE_INSTANTIATIONS list; other templates use the
880 DECL_TEMPLATE_SPECIALIZATIONS list. */
881 if (!class_specializations_p
882 && TREE_CODE (DECL_TEMPLATE_RESULT (tmpl)) == TYPE_DECL)
883 sp = &DECL_TEMPLATE_INSTANTIATIONS (tmpl);
885 sp = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
887 /* Iterate through the list until we find a matching template. */
888 while (*sp != NULL_TREE)
892 if (comp_template_args (TREE_PURPOSE (spec), args))
894 /* Use the move-to-front heuristic to speed up future
898 *sp = TREE_CHAIN (*sp);
899 TREE_CHAIN (spec) = *head;
902 return TREE_VALUE (spec);
904 sp = &TREE_CHAIN (spec);
911 /* Like retrieve_specialization, but for local declarations. */
914 retrieve_local_specialization (tree tmpl)
916 tree spec = htab_find_with_hash (local_specializations, tmpl,
917 htab_hash_pointer (tmpl));
918 return spec ? TREE_PURPOSE (spec) : NULL_TREE;
921 /* Returns nonzero iff DECL is a specialization of TMPL. */
924 is_specialization_of (tree decl, tree tmpl)
928 if (TREE_CODE (decl) == FUNCTION_DECL)
932 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE)
938 gcc_assert (TREE_CODE (decl) == TYPE_DECL);
940 for (t = TREE_TYPE (decl);
942 t = CLASSTYPE_USE_TEMPLATE (t)
943 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE)
944 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl)))
951 /* Returns nonzero iff DECL is a specialization of friend declaration
952 FRIEND according to [temp.friend]. */
955 is_specialization_of_friend (tree decl, tree friend)
957 bool need_template = true;
960 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL
961 || TREE_CODE (decl) == TYPE_DECL);
963 /* For [temp.friend/6] when FRIEND is an ordinary member function
964 of a template class, we want to check if DECL is a specialization
966 if (TREE_CODE (friend) == FUNCTION_DECL
967 && DECL_TEMPLATE_INFO (friend)
968 && !DECL_USE_TEMPLATE (friend))
970 /* We want a TEMPLATE_DECL for `is_specialization_of'. */
971 friend = DECL_TI_TEMPLATE (friend);
972 need_template = false;
974 else if (TREE_CODE (friend) == TEMPLATE_DECL
975 && !PRIMARY_TEMPLATE_P (friend))
976 need_template = false;
978 /* There is nothing to do if this is not a template friend. */
979 if (TREE_CODE (friend) != TEMPLATE_DECL)
982 if (is_specialization_of (decl, friend))
986 A member of a class template may be declared to be a friend of a
987 non-template class. In this case, the corresponding member of
988 every specialization of the class template is a friend of the
989 class granting friendship.
991 For example, given a template friend declaration
993 template <class T> friend void A<T>::f();
995 the member function below is considered a friend
997 template <> struct A<int> {
1001 For this type of template friend, TEMPLATE_DEPTH below will be
1002 nonzero. To determine if DECL is a friend of FRIEND, we first
1003 check if the enclosing class is a specialization of another. */
1005 template_depth = template_class_depth (DECL_CONTEXT (friend));
1007 && DECL_CLASS_SCOPE_P (decl)
1008 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)),
1009 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend))))
1011 /* Next, we check the members themselves. In order to handle
1012 a few tricky cases, such as when FRIEND's are
1014 template <class T> friend void A<T>::g(T t);
1015 template <class T> template <T t> friend void A<T>::h();
1019 void A<int>::g(int);
1020 template <int> void A<int>::h();
1022 we need to figure out ARGS, the template arguments from
1023 the context of DECL. This is required for template substitution
1024 of `T' in the function parameter of `g' and template parameter
1025 of `h' in the above examples. Here ARGS corresponds to `int'. */
1027 tree context = DECL_CONTEXT (decl);
1028 tree args = NULL_TREE;
1029 int current_depth = 0;
1031 while (current_depth < template_depth)
1033 if (CLASSTYPE_TEMPLATE_INFO (context))
1035 if (current_depth == 0)
1036 args = TYPE_TI_ARGS (context);
1038 args = add_to_template_args (TYPE_TI_ARGS (context), args);
1041 context = TYPE_CONTEXT (context);
1044 if (TREE_CODE (decl) == FUNCTION_DECL)
1049 tree friend_args_type;
1050 tree decl_args_type;
1052 /* Make sure that both DECL and FRIEND are templates or
1054 is_template = DECL_TEMPLATE_INFO (decl)
1055 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl));
1056 if (need_template ^ is_template)
1058 else if (is_template)
1060 /* If both are templates, check template parameter list. */
1062 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1064 if (!comp_template_parms
1065 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)),
1069 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl));
1072 decl_type = TREE_TYPE (decl);
1074 friend_type = tsubst_function_type (TREE_TYPE (friend), args,
1075 tf_none, NULL_TREE);
1076 if (friend_type == error_mark_node)
1079 /* Check if return types match. */
1080 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type)))
1083 /* Check if function parameter types match, ignoring the
1084 `this' parameter. */
1085 friend_args_type = TYPE_ARG_TYPES (friend_type);
1086 decl_args_type = TYPE_ARG_TYPES (decl_type);
1087 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend))
1088 friend_args_type = TREE_CHAIN (friend_args_type);
1089 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1090 decl_args_type = TREE_CHAIN (decl_args_type);
1092 return compparms (decl_args_type, friend_args_type);
1096 /* DECL is a TYPE_DECL */
1098 tree decl_type = TREE_TYPE (decl);
1100 /* Make sure that both DECL and FRIEND are templates or
1103 = CLASSTYPE_TEMPLATE_INFO (decl_type)
1104 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type));
1106 if (need_template ^ is_template)
1108 else if (is_template)
1111 /* If both are templates, check the name of the two
1112 TEMPLATE_DECL's first because is_friend didn't. */
1113 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type))
1114 != DECL_NAME (friend))
1117 /* Now check template parameter list. */
1119 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend),
1121 return comp_template_parms
1122 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)),
1126 return (DECL_NAME (decl)
1127 == DECL_NAME (friend));
1133 /* Register the specialization SPEC as a specialization of TMPL with
1134 the indicated ARGS. IS_FRIEND indicates whether the specialization
1135 is actually just a friend declaration. Returns SPEC, or an
1136 equivalent prior declaration, if available. */
1139 register_specialization (tree spec, tree tmpl, tree args, bool is_friend)
1143 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
1145 if (TREE_CODE (spec) == FUNCTION_DECL
1146 && uses_template_parms (DECL_TI_ARGS (spec)))
1147 /* This is the FUNCTION_DECL for a partial instantiation. Don't
1148 register it; we want the corresponding TEMPLATE_DECL instead.
1149 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than
1150 the more obvious `uses_template_parms (spec)' to avoid problems
1151 with default function arguments. In particular, given
1152 something like this:
1154 template <class T> void f(T t1, T t = T())
1156 the default argument expression is not substituted for in an
1157 instantiation unless and until it is actually needed. */
1160 fn = retrieve_specialization (tmpl, args,
1161 /*class_specializations_p=*/false);
1162 /* We can sometimes try to re-register a specialization that we've
1163 already got. In particular, regenerate_decl_from_template calls
1164 duplicate_decls which will update the specialization list. But,
1165 we'll still get called again here anyhow. It's more convenient
1166 to simply allow this than to try to prevent it. */
1169 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec))
1171 if (DECL_TEMPLATE_INSTANTIATION (fn))
1174 || DECL_EXPLICIT_INSTANTIATION (fn))
1176 error ("specialization of %qD after instantiation",
1182 /* This situation should occur only if the first
1183 specialization is an implicit instantiation, the
1184 second is an explicit specialization, and the
1185 implicit instantiation has not yet been used. That
1186 situation can occur if we have implicitly
1187 instantiated a member function and then specialized
1190 We can also wind up here if a friend declaration that
1191 looked like an instantiation turns out to be a
1194 template <class T> void foo(T);
1195 class S { friend void foo<>(int) };
1196 template <> void foo(int);
1198 We transform the existing DECL in place so that any
1199 pointers to it become pointers to the updated
1202 If there was a definition for the template, but not
1203 for the specialization, we want this to look as if
1204 there were no definition, and vice versa. */
1205 DECL_INITIAL (fn) = NULL_TREE;
1206 duplicate_decls (spec, fn, is_friend);
1207 check_specialization_namespace (fn);
1212 else if (DECL_TEMPLATE_SPECIALIZATION (fn))
1214 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec))
1215 /* Dup decl failed, but this is a new definition. Set the
1216 line number so any errors match this new
1218 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec);
1224 /* A specialization must be declared in the same namespace as the
1225 template it is specializing. */
1226 if (DECL_TEMPLATE_SPECIALIZATION (spec)
1227 && !check_specialization_namespace (tmpl))
1228 DECL_CONTEXT (spec) = decl_namespace_context (tmpl);
1230 if (!optimize_specialization_lookup_p (tmpl))
1231 DECL_TEMPLATE_SPECIALIZATIONS (tmpl)
1232 = tree_cons (args, spec, DECL_TEMPLATE_SPECIALIZATIONS (tmpl));
1237 /* Unregister the specialization SPEC as a specialization of TMPL.
1238 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true
1239 if the SPEC was listed as a specialization of TMPL. */
1242 reregister_specialization (tree spec, tree tmpl, tree new_spec)
1246 for (s = &DECL_TEMPLATE_SPECIALIZATIONS (tmpl);
1248 s = &TREE_CHAIN (*s))
1249 if (TREE_VALUE (*s) == spec)
1252 *s = TREE_CHAIN (*s);
1254 TREE_VALUE (*s) = new_spec;
1261 /* Compare an entry in the local specializations hash table P1 (which
1262 is really a pointer to a TREE_LIST) with P2 (which is really a
1266 eq_local_specializations (const void *p1, const void *p2)
1268 return TREE_VALUE ((tree) p1) == (tree) p2;
1271 /* Hash P1, an entry in the local specializations table. */
1274 hash_local_specialization (const void* p1)
1276 return htab_hash_pointer (TREE_VALUE ((tree) p1));
1279 /* Like register_specialization, but for local declarations. We are
1280 registering SPEC, an instantiation of TMPL. */
1283 register_local_specialization (tree spec, tree tmpl)
1287 slot = htab_find_slot_with_hash (local_specializations, tmpl,
1288 htab_hash_pointer (tmpl), INSERT);
1289 *slot = build_tree_list (spec, tmpl);
1292 /* Print the list of candidate FNS in an error message. */
1295 print_candidates (tree fns)
1299 const char *str = "candidates are:";
1301 for (fn = fns; fn != NULL_TREE; fn = TREE_CHAIN (fn))
1305 for (f = TREE_VALUE (fn); f; f = OVL_NEXT (f))
1306 error ("%s %+#D", str, OVL_CURRENT (f));
1311 /* Returns the template (one of the functions given by TEMPLATE_ID)
1312 which can be specialized to match the indicated DECL with the
1313 explicit template args given in TEMPLATE_ID. The DECL may be
1314 NULL_TREE if none is available. In that case, the functions in
1315 TEMPLATE_ID are non-members.
1317 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a
1318 specialization of a member template.
1320 The TEMPLATE_COUNT is the number of references to qualifying
1321 template classes that appeared in the name of the function. See
1322 check_explicit_specialization for a more accurate description.
1324 The template args (those explicitly specified and those deduced)
1325 are output in a newly created vector *TARGS_OUT.
1327 If it is impossible to determine the result, an error message is
1328 issued. The error_mark_node is returned to indicate failure. */
1331 determine_specialization (tree template_id,
1334 int need_member_template,
1339 tree explicit_targs;
1340 tree candidates = NULL_TREE;
1341 tree templates = NULL_TREE;
1343 struct cp_binding_level *b;
1345 *targs_out = NULL_TREE;
1347 if (template_id == error_mark_node)
1348 return error_mark_node;
1350 fns = TREE_OPERAND (template_id, 0);
1351 explicit_targs = TREE_OPERAND (template_id, 1);
1353 if (fns == error_mark_node)
1354 return error_mark_node;
1356 /* Check for baselinks. */
1357 if (BASELINK_P (fns))
1358 fns = BASELINK_FUNCTIONS (fns);
1360 if (!is_overloaded_fn (fns))
1362 error ("%qD is not a function template", fns);
1363 return error_mark_node;
1366 /* Count the number of template headers specified for this
1369 for (b = current_binding_level;
1370 b->kind == sk_template_parms;
1374 for (; fns; fns = OVL_NEXT (fns))
1376 tree fn = OVL_CURRENT (fns);
1378 if (TREE_CODE (fn) == TEMPLATE_DECL)
1380 tree decl_arg_types;
1383 /* DECL might be a specialization of FN. */
1385 /* Adjust the type of DECL in case FN is a static member. */
1386 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1387 if (DECL_STATIC_FUNCTION_P (fn)
1388 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1389 decl_arg_types = TREE_CHAIN (decl_arg_types);
1391 /* Check that the number of function parameters matches.
1393 template <class T> void f(int i = 0);
1394 template <> void f<int>();
1395 The specialization f<int> is invalid but is not caught
1396 by get_bindings below. */
1398 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn));
1399 if (list_length (fn_arg_types) != list_length (decl_arg_types))
1402 /* For a non-static member function, we need to make sure that
1403 the const qualification is the same. This can be done by
1404 checking the 'this' in the argument list. */
1405 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)
1406 && !same_type_p (TREE_VALUE (fn_arg_types),
1407 TREE_VALUE (decl_arg_types)))
1410 /* In case of explicit specialization, we need to check if
1411 the number of template headers appearing in the specialization
1412 is correct. This is usually done in check_explicit_specialization,
1413 but the check done there cannot be exhaustive when specializing
1414 member functions. Consider the following code:
1416 template <> void A<int>::f(int);
1417 template <> template <> void A<int>::f(int);
1419 Assuming that A<int> is not itself an explicit specialization
1420 already, the first line specializes "f" which is a non-template
1421 member function, whilst the second line specializes "f" which
1422 is a template member function. So both lines are syntactically
1423 correct, and check_explicit_specialization does not reject
1426 Here, we can do better, as we are matching the specialization
1427 against the declarations. We count the number of template
1428 headers, and we check if they match TEMPLATE_COUNT + 1
1429 (TEMPLATE_COUNT is the number of qualifying template classes,
1430 plus there must be another header for the member template
1433 Notice that if header_count is zero, this is not a
1434 specialization but rather a template instantiation, so there
1435 is no check we can perform here. */
1436 if (header_count && header_count != template_count + 1)
1439 /* Check that the number of template arguments at the
1440 innermost level for DECL is the same as for FN. */
1441 if (current_binding_level->kind == sk_template_parms
1442 && !current_binding_level->explicit_spec_p
1443 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn))
1444 != TREE_VEC_LENGTH (TREE_VALUE (current_template_parms))))
1447 /* See whether this function might be a specialization of this
1449 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true);
1452 /* We cannot deduce template arguments that when used to
1453 specialize TMPL will produce DECL. */
1456 /* Save this template, and the arguments deduced. */
1457 templates = tree_cons (targs, fn, templates);
1459 else if (need_member_template)
1460 /* FN is an ordinary member function, and we need a
1461 specialization of a member template. */
1463 else if (TREE_CODE (fn) != FUNCTION_DECL)
1464 /* We can get IDENTIFIER_NODEs here in certain erroneous
1467 else if (!DECL_FUNCTION_MEMBER_P (fn))
1468 /* This is just an ordinary non-member function. Nothing can
1469 be a specialization of that. */
1471 else if (DECL_ARTIFICIAL (fn))
1472 /* Cannot specialize functions that are created implicitly. */
1476 tree decl_arg_types;
1478 /* This is an ordinary member function. However, since
1479 we're here, we can assume it's enclosing class is a
1480 template class. For example,
1482 template <typename T> struct S { void f(); };
1483 template <> void S<int>::f() {}
1485 Here, S<int>::f is a non-template, but S<int> is a
1486 template class. If FN has the same type as DECL, we
1487 might be in business. */
1489 if (!DECL_TEMPLATE_INFO (fn))
1490 /* Its enclosing class is an explicit specialization
1491 of a template class. This is not a candidate. */
1494 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
1495 TREE_TYPE (TREE_TYPE (fn))))
1496 /* The return types differ. */
1499 /* Adjust the type of DECL in case FN is a static member. */
1500 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl));
1501 if (DECL_STATIC_FUNCTION_P (fn)
1502 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1503 decl_arg_types = TREE_CHAIN (decl_arg_types);
1505 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)),
1508 candidates = tree_cons (NULL_TREE, fn, candidates);
1512 if (templates && TREE_CHAIN (templates))
1518 It is possible for a specialization with a given function
1519 signature to be instantiated from more than one function
1520 template. In such cases, explicit specification of the
1521 template arguments must be used to uniquely identify the
1522 function template specialization being specialized.
1524 Note that here, there's no suggestion that we're supposed to
1525 determine which of the candidate templates is most
1526 specialized. However, we, also have:
1530 Partial ordering of overloaded function template
1531 declarations is used in the following contexts to select
1532 the function template to which a function template
1533 specialization refers:
1535 -- when an explicit specialization refers to a function
1538 So, we do use the partial ordering rules, at least for now.
1539 This extension can only serve to make invalid programs valid,
1540 so it's safe. And, there is strong anecdotal evidence that
1541 the committee intended the partial ordering rules to apply;
1542 the EDG front-end has that behavior, and John Spicer claims
1543 that the committee simply forgot to delete the wording in
1544 [temp.expl.spec]. */
1545 tree tmpl = most_specialized (templates, decl, explicit_targs);
1546 if (tmpl && tmpl != error_mark_node)
1548 targs = get_bindings (tmpl, decl, explicit_targs, /*check_ret=*/true);
1549 templates = tree_cons (targs, tmpl, NULL_TREE);
1553 if (templates == NULL_TREE && candidates == NULL_TREE)
1555 error ("template-id %qD for %q+D does not match any template "
1556 "declaration", template_id, decl);
1557 return error_mark_node;
1559 else if ((templates && TREE_CHAIN (templates))
1560 || (candidates && TREE_CHAIN (candidates))
1561 || (templates && candidates))
1563 error ("ambiguous template specialization %qD for %q+D",
1565 chainon (candidates, templates);
1566 print_candidates (candidates);
1567 return error_mark_node;
1570 /* We have one, and exactly one, match. */
1573 /* It was a specialization of an ordinary member function in a
1575 *targs_out = copy_node (DECL_TI_ARGS (TREE_VALUE (candidates)));
1576 return DECL_TI_TEMPLATE (TREE_VALUE (candidates));
1579 /* It was a specialization of a template. */
1580 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates)));
1581 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs))
1583 *targs_out = copy_node (targs);
1584 SET_TMPL_ARGS_LEVEL (*targs_out,
1585 TMPL_ARGS_DEPTH (*targs_out),
1586 TREE_PURPOSE (templates));
1589 *targs_out = TREE_PURPOSE (templates);
1590 return TREE_VALUE (templates);
1593 /* Returns a chain of parameter types, exactly like the SPEC_TYPES,
1594 but with the default argument values filled in from those in the
1598 copy_default_args_to_explicit_spec_1 (tree spec_types,
1601 tree new_spec_types;
1606 if (spec_types == void_list_node)
1607 return void_list_node;
1609 /* Substitute into the rest of the list. */
1611 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types),
1612 TREE_CHAIN (tmpl_types));
1614 /* Add the default argument for this parameter. */
1615 return hash_tree_cons (TREE_PURPOSE (tmpl_types),
1616 TREE_VALUE (spec_types),
1620 /* DECL is an explicit specialization. Replicate default arguments
1621 from the template it specializes. (That way, code like:
1623 template <class T> void f(T = 3);
1624 template <> void f(double);
1627 works, as required.) An alternative approach would be to look up
1628 the correct default arguments at the call-site, but this approach
1629 is consistent with how implicit instantiations are handled. */
1632 copy_default_args_to_explicit_spec (tree decl)
1637 tree new_spec_types;
1641 tree object_type = NULL_TREE;
1642 tree in_charge = NULL_TREE;
1643 tree vtt = NULL_TREE;
1645 /* See if there's anything we need to do. */
1646 tmpl = DECL_TI_TEMPLATE (decl);
1647 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl)));
1648 for (t = tmpl_types; t; t = TREE_CHAIN (t))
1649 if (TREE_PURPOSE (t))
1654 old_type = TREE_TYPE (decl);
1655 spec_types = TYPE_ARG_TYPES (old_type);
1657 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
1659 /* Remove the this pointer, but remember the object's type for
1661 object_type = TREE_TYPE (TREE_VALUE (spec_types));
1662 spec_types = TREE_CHAIN (spec_types);
1663 tmpl_types = TREE_CHAIN (tmpl_types);
1665 if (DECL_HAS_IN_CHARGE_PARM_P (decl))
1667 /* DECL may contain more parameters than TMPL due to the extra
1668 in-charge parameter in constructors and destructors. */
1669 in_charge = spec_types;
1670 spec_types = TREE_CHAIN (spec_types);
1672 if (DECL_HAS_VTT_PARM_P (decl))
1675 spec_types = TREE_CHAIN (spec_types);
1679 /* Compute the merged default arguments. */
1681 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types);
1683 /* Compute the new FUNCTION_TYPE. */
1687 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt),
1692 /* Put the in-charge parameter back. */
1693 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge),
1694 TREE_VALUE (in_charge),
1697 new_type = build_method_type_directly (object_type,
1698 TREE_TYPE (old_type),
1702 new_type = build_function_type (TREE_TYPE (old_type),
1704 new_type = cp_build_type_attribute_variant (new_type,
1705 TYPE_ATTRIBUTES (old_type));
1706 new_type = build_exception_variant (new_type,
1707 TYPE_RAISES_EXCEPTIONS (old_type));
1708 TREE_TYPE (decl) = new_type;
1711 /* Check to see if the function just declared, as indicated in
1712 DECLARATOR, and in DECL, is a specialization of a function
1713 template. We may also discover that the declaration is an explicit
1714 instantiation at this point.
1716 Returns DECL, or an equivalent declaration that should be used
1717 instead if all goes well. Issues an error message if something is
1718 amiss. Returns error_mark_node if the error is not easily
1721 FLAGS is a bitmask consisting of the following flags:
1723 2: The function has a definition.
1724 4: The function is a friend.
1726 The TEMPLATE_COUNT is the number of references to qualifying
1727 template classes that appeared in the name of the function. For
1730 template <class T> struct S { void f(); };
1733 the TEMPLATE_COUNT would be 1. However, explicitly specialized
1734 classes are not counted in the TEMPLATE_COUNT, so that in
1736 template <class T> struct S {};
1737 template <> struct S<int> { void f(); }
1738 template <> void S<int>::f();
1740 the TEMPLATE_COUNT would be 0. (Note that this declaration is
1741 invalid; there should be no template <>.)
1743 If the function is a specialization, it is marked as such via
1744 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO
1745 is set up correctly, and it is added to the list of specializations
1746 for that template. */
1749 check_explicit_specialization (tree declarator,
1754 int have_def = flags & 2;
1755 int is_friend = flags & 4;
1756 int specialization = 0;
1757 int explicit_instantiation = 0;
1758 int member_specialization = 0;
1759 tree ctype = DECL_CLASS_CONTEXT (decl);
1760 tree dname = DECL_NAME (decl);
1765 if (!processing_specialization)
1768 tsk = tsk_excessive_parms;
1771 tsk = current_tmpl_spec_kind (template_count);
1776 if (processing_specialization)
1779 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1781 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1784 /* This could be something like:
1786 template <class T> void f(T);
1787 class S { friend void f<>(int); } */
1791 /* This case handles bogus declarations like template <>
1792 template <class T> void f<int>(); */
1794 error ("template-id %qD in declaration of primary template",
1801 case tsk_invalid_member_spec:
1802 /* The error has already been reported in
1803 check_specialization_scope. */
1804 return error_mark_node;
1806 case tsk_invalid_expl_inst:
1807 error ("template parameter list used in explicit instantiation");
1813 error ("definition provided for explicit instantiation");
1815 explicit_instantiation = 1;
1818 case tsk_excessive_parms:
1819 case tsk_insufficient_parms:
1820 if (tsk == tsk_excessive_parms)
1821 error ("too many template parameter lists in declaration of %qD",
1823 else if (template_header_count)
1824 error("too few template parameter lists in declaration of %qD", decl);
1826 error("explicit specialization of %qD must be introduced by "
1827 "%<template <>%>", decl);
1831 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
1833 member_specialization = 1;
1839 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR)
1841 /* This case handles bogus declarations like template <>
1842 template <class T> void f<int>(); */
1844 if (uses_template_parms (declarator))
1845 error ("function template partial specialization %qD "
1846 "is not allowed", declarator);
1848 error ("template-id %qD in declaration of primary template",
1853 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype))
1854 /* This is a specialization of a member template, without
1855 specialization the containing class. Something like:
1857 template <class T> struct S {
1858 template <class U> void f (U);
1860 template <> template <class U> void S<int>::f(U) {}
1862 That's a specialization -- but of the entire template. */
1870 if (specialization || member_specialization)
1872 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl));
1873 for (; t; t = TREE_CHAIN (t))
1874 if (TREE_PURPOSE (t))
1877 ("default argument specified in explicit specialization");
1880 if (current_lang_name == lang_name_c)
1881 error ("template specialization with C linkage");
1884 if (specialization || member_specialization || explicit_instantiation)
1886 tree tmpl = NULL_TREE;
1887 tree targs = NULL_TREE;
1889 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */
1890 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR)
1894 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE);
1899 /* If there is no class context, the explicit instantiation
1900 must be at namespace scope. */
1901 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl));
1903 /* Find the namespace binding, using the declaration
1905 fns = namespace_binding (dname, CP_DECL_CONTEXT (decl));
1906 if (!fns || !is_overloaded_fn (fns))
1908 error ("%qD is not a template function", dname);
1909 fns = error_mark_node;
1913 declarator = lookup_template_function (fns, NULL_TREE);
1916 if (declarator == error_mark_node)
1917 return error_mark_node;
1919 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype))
1921 if (!explicit_instantiation)
1922 /* A specialization in class scope. This is invalid,
1923 but the error will already have been flagged by
1924 check_specialization_scope. */
1925 return error_mark_node;
1928 /* It's not valid to write an explicit instantiation in
1931 class C { template void f(); }
1933 This case is caught by the parser. However, on
1936 template class C { void f(); };
1938 (which is invalid) we can get here. The error will be
1945 else if (ctype != NULL_TREE
1946 && (TREE_CODE (TREE_OPERAND (declarator, 0)) ==
1949 /* Find the list of functions in ctype that have the same
1950 name as the declared function. */
1951 tree name = TREE_OPERAND (declarator, 0);
1952 tree fns = NULL_TREE;
1955 if (constructor_name_p (name, ctype))
1957 int is_constructor = DECL_CONSTRUCTOR_P (decl);
1959 if (is_constructor ? !TYPE_HAS_CONSTRUCTOR (ctype)
1960 : !CLASSTYPE_DESTRUCTORS (ctype))
1962 /* From [temp.expl.spec]:
1964 If such an explicit specialization for the member
1965 of a class template names an implicitly-declared
1966 special member function (clause _special_), the
1967 program is ill-formed.
1969 Similar language is found in [temp.explicit]. */
1970 error ("specialization of implicitly-declared special member function");
1971 return error_mark_node;
1974 name = is_constructor ? ctor_identifier : dtor_identifier;
1977 if (!DECL_CONV_FN_P (decl))
1979 idx = lookup_fnfields_1 (ctype, name);
1981 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx);
1985 VEC(tree,gc) *methods;
1988 /* For a type-conversion operator, we cannot do a
1989 name-based lookup. We might be looking for `operator
1990 int' which will be a specialization of `operator T'.
1991 So, we find *all* the conversion operators, and then
1992 select from them. */
1995 methods = CLASSTYPE_METHOD_VEC (ctype);
1997 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT;
1998 VEC_iterate (tree, methods, idx, ovl);
2001 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl)))
2002 /* There are no more conversion functions. */
2005 /* Glue all these conversion functions together
2006 with those we already have. */
2007 for (; ovl; ovl = OVL_NEXT (ovl))
2008 fns = ovl_cons (OVL_CURRENT (ovl), fns);
2012 if (fns == NULL_TREE)
2014 error ("no member function %qD declared in %qT", name, ctype);
2015 return error_mark_node;
2018 TREE_OPERAND (declarator, 0) = fns;
2021 /* Figure out what exactly is being specialized at this point.
2022 Note that for an explicit instantiation, even one for a
2023 member function, we cannot tell apriori whether the
2024 instantiation is for a member template, or just a member
2025 function of a template class. Even if a member template is
2026 being instantiated, the member template arguments may be
2027 elided if they can be deduced from the rest of the
2029 tmpl = determine_specialization (declarator, decl,
2031 member_specialization,
2034 if (!tmpl || tmpl == error_mark_node)
2035 /* We couldn't figure out what this declaration was
2037 return error_mark_node;
2040 tree gen_tmpl = most_general_template (tmpl);
2042 if (explicit_instantiation)
2044 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that
2045 is done by do_decl_instantiation later. */
2047 int arg_depth = TMPL_ARGS_DEPTH (targs);
2048 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
2050 if (arg_depth > parm_depth)
2052 /* If TMPL is not the most general template (for
2053 example, if TMPL is a friend template that is
2054 injected into namespace scope), then there will
2055 be too many levels of TARGS. Remove some of them
2060 new_targs = make_tree_vec (parm_depth);
2061 for (i = arg_depth - parm_depth; i < arg_depth; ++i)
2062 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth))
2063 = TREE_VEC_ELT (targs, i);
2067 return instantiate_template (tmpl, targs, tf_error);
2070 /* If we thought that the DECL was a member function, but it
2071 turns out to be specializing a static member function,
2072 make DECL a static member function as well. */
2073 if (DECL_STATIC_FUNCTION_P (tmpl)
2074 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
2075 revert_static_member_fn (decl);
2077 /* If this is a specialization of a member template of a
2078 template class. In we want to return the TEMPLATE_DECL,
2079 not the specialization of it. */
2080 if (tsk == tsk_template)
2082 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
2083 DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)) = NULL_TREE;
2086 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl);
2087 DECL_SOURCE_LOCATION (DECL_TEMPLATE_RESULT (tmpl))
2088 = DECL_SOURCE_LOCATION (decl);
2089 /* We want to use the argument list specified in the
2090 definition, not in the original declaration. */
2091 DECL_ARGUMENTS (DECL_TEMPLATE_RESULT (tmpl))
2092 = DECL_ARGUMENTS (decl);
2097 /* Set up the DECL_TEMPLATE_INFO for DECL. */
2098 DECL_TEMPLATE_INFO (decl) = tree_cons (tmpl, targs, NULL_TREE);
2100 /* Inherit default function arguments from the template
2101 DECL is specializing. */
2102 copy_default_args_to_explicit_spec (decl);
2104 /* This specialization has the same protection as the
2105 template it specializes. */
2106 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl);
2107 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl);
2108 /* The specialization has the same visibility as the
2109 template it specializes. */
2110 if (DECL_VISIBILITY_SPECIFIED (gen_tmpl))
2112 DECL_VISIBILITY_SPECIFIED (decl) = 1;
2113 DECL_VISIBILITY (decl) = DECL_VISIBILITY (gen_tmpl);
2115 /* If DECL is a friend declaration, declared using an
2116 unqualified name, the namespace associated with DECL may
2117 have been set incorrectly. For example, in:
2119 template <typename T> void f(T);
2121 struct S { friend void f<int>(int); }
2124 we will have set the DECL_CONTEXT for the friend
2125 declaration to N, rather than to the global namespace. */
2126 if (DECL_NAMESPACE_SCOPE_P (decl))
2127 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl);
2129 if (is_friend && !have_def)
2130 /* This is not really a declaration of a specialization.
2131 It's just the name of an instantiation. But, it's not
2132 a request for an instantiation, either. */
2133 SET_DECL_IMPLICIT_INSTANTIATION (decl);
2134 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl))
2135 /* This is indeed a specialization. In case of constructors
2136 and destructors, we need in-charge and not-in-charge
2137 versions in V3 ABI. */
2138 clone_function_decl (decl, /*update_method_vec_p=*/0);
2140 /* Register this specialization so that we can find it
2142 decl = register_specialization (decl, gen_tmpl, targs, is_friend);
2149 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template
2150 parameters. These are represented in the same format used for
2151 DECL_TEMPLATE_PARMS. */
2154 comp_template_parms (tree parms1, tree parms2)
2159 if (parms1 == parms2)
2162 for (p1 = parms1, p2 = parms2;
2163 p1 != NULL_TREE && p2 != NULL_TREE;
2164 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2))
2166 tree t1 = TREE_VALUE (p1);
2167 tree t2 = TREE_VALUE (p2);
2170 gcc_assert (TREE_CODE (t1) == TREE_VEC);
2171 gcc_assert (TREE_CODE (t2) == TREE_VEC);
2173 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2))
2176 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i)
2178 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i));
2179 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i));
2181 if (TREE_CODE (parm1) != TREE_CODE (parm2))
2184 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM)
2186 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2)))
2191 if ((p1 != NULL_TREE) != (p2 != NULL_TREE))
2192 /* One set of parameters has more parameters lists than the
2199 /* Complain if DECL shadows a template parameter.
2201 [temp.local]: A template-parameter shall not be redeclared within its
2202 scope (including nested scopes). */
2205 check_template_shadow (tree decl)
2209 /* If we're not in a template, we can't possibly shadow a template
2211 if (!current_template_parms)
2214 /* Figure out what we're shadowing. */
2215 if (TREE_CODE (decl) == OVERLOAD)
2216 decl = OVL_CURRENT (decl);
2217 olddecl = innermost_non_namespace_value (DECL_NAME (decl));
2219 /* If there's no previous binding for this name, we're not shadowing
2220 anything, let alone a template parameter. */
2224 /* If we're not shadowing a template parameter, we're done. Note
2225 that OLDDECL might be an OVERLOAD (or perhaps even an
2226 ERROR_MARK), so we can't just blithely assume it to be a _DECL
2228 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl))
2231 /* We check for decl != olddecl to avoid bogus errors for using a
2232 name inside a class. We check TPFI to avoid duplicate errors for
2233 inline member templates. */
2235 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms))
2238 error ("declaration of %q+#D", decl);
2239 error (" shadows template parm %q+#D", olddecl);
2242 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL,
2243 ORIG_LEVEL, DECL, and TYPE. */
2246 build_template_parm_index (int index,
2252 tree t = make_node (TEMPLATE_PARM_INDEX);
2253 TEMPLATE_PARM_IDX (t) = index;
2254 TEMPLATE_PARM_LEVEL (t) = level;
2255 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level;
2256 TEMPLATE_PARM_DECL (t) = decl;
2257 TREE_TYPE (t) = type;
2258 TREE_CONSTANT (t) = TREE_CONSTANT (decl);
2259 TREE_INVARIANT (t) = TREE_INVARIANT (decl);
2260 TREE_READONLY (t) = TREE_READONLY (decl);
2265 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose
2266 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a
2267 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a
2268 new one is created. */
2271 reduce_template_parm_level (tree index, tree type, int levels)
2273 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE
2274 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index))
2275 != TEMPLATE_PARM_LEVEL (index) - levels))
2277 tree orig_decl = TEMPLATE_PARM_DECL (index);
2280 decl = build_decl (TREE_CODE (orig_decl), DECL_NAME (orig_decl), type);
2281 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl);
2282 TREE_INVARIANT (decl) = TREE_INVARIANT (orig_decl);
2283 TREE_READONLY (decl) = TREE_READONLY (orig_decl);
2284 DECL_ARTIFICIAL (decl) = 1;
2285 SET_DECL_TEMPLATE_PARM_P (decl);
2287 t = build_template_parm_index (TEMPLATE_PARM_IDX (index),
2288 TEMPLATE_PARM_LEVEL (index) - levels,
2289 TEMPLATE_PARM_ORIG_LEVEL (index),
2291 TEMPLATE_PARM_DESCENDANTS (index) = t;
2293 /* Template template parameters need this. */
2294 if (TREE_CODE (decl) != CONST_DECL)
2295 DECL_TEMPLATE_PARMS (decl)
2296 = DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index));
2299 return TEMPLATE_PARM_DESCENDANTS (index);
2302 /* Process information from new template parameter NEXT and append it to the
2303 LIST being built. This new parameter is a non-type parameter iff
2304 IS_NON_TYPE is true. */
2307 process_template_parm (tree list, tree next, bool is_non_type)
2315 gcc_assert (TREE_CODE (parm) == TREE_LIST);
2316 defval = TREE_PURPOSE (parm);
2320 tree p = TREE_VALUE (tree_last (list));
2322 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL)
2323 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p));
2325 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p));
2333 parm = TREE_VALUE (parm);
2335 SET_DECL_TEMPLATE_PARM_P (parm);
2339 The top-level cv-qualifiers on the template-parameter are
2340 ignored when determining its type. */
2341 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm));
2343 /* A template parameter is not modifiable. */
2344 TREE_CONSTANT (parm) = 1;
2345 TREE_INVARIANT (parm) = 1;
2346 TREE_READONLY (parm) = 1;
2347 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1))
2348 TREE_TYPE (parm) = void_type_node;
2349 decl = build_decl (CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm));
2350 TREE_CONSTANT (decl) = 1;
2351 TREE_INVARIANT (decl) = 1;
2352 TREE_READONLY (decl) = 1;
2353 DECL_INITIAL (parm) = DECL_INITIAL (decl)
2354 = build_template_parm_index (idx, processing_template_decl,
2355 processing_template_decl,
2356 decl, TREE_TYPE (parm));
2361 parm = TREE_VALUE (TREE_VALUE (parm));
2363 if (parm && TREE_CODE (parm) == TEMPLATE_DECL)
2365 t = make_aggr_type (TEMPLATE_TEMPLATE_PARM);
2366 /* This is for distinguishing between real templates and template
2367 template parameters */
2368 TREE_TYPE (parm) = t;
2369 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t;
2374 t = make_aggr_type (TEMPLATE_TYPE_PARM);
2375 /* parm is either IDENTIFIER_NODE or NULL_TREE. */
2376 decl = build_decl (TYPE_DECL, parm, t);
2379 TYPE_NAME (t) = decl;
2380 TYPE_STUB_DECL (t) = decl;
2382 TEMPLATE_TYPE_PARM_INDEX (t)
2383 = build_template_parm_index (idx, processing_template_decl,
2384 processing_template_decl,
2385 decl, TREE_TYPE (parm));
2387 DECL_ARTIFICIAL (decl) = 1;
2388 SET_DECL_TEMPLATE_PARM_P (decl);
2390 parm = build_tree_list (defval, parm);
2391 return chainon (list, parm);
2394 /* The end of a template parameter list has been reached. Process the
2395 tree list into a parameter vector, converting each parameter into a more
2396 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others
2400 end_template_parm_list (tree parms)
2404 tree saved_parmlist = make_tree_vec (list_length (parms));
2406 current_template_parms
2407 = tree_cons (size_int (processing_template_decl),
2408 saved_parmlist, current_template_parms);
2410 for (parm = parms, nparms = 0; parm; parm = next, nparms++)
2412 next = TREE_CHAIN (parm);
2413 TREE_VEC_ELT (saved_parmlist, nparms) = parm;
2414 TREE_CHAIN (parm) = NULL_TREE;
2417 --processing_template_parmlist;
2419 return saved_parmlist;
2422 /* end_template_decl is called after a template declaration is seen. */
2425 end_template_decl (void)
2427 reset_specialization ();
2429 if (! processing_template_decl)
2432 /* This matches the pushlevel in begin_template_parm_list. */
2435 --processing_template_decl;
2436 current_template_parms = TREE_CHAIN (current_template_parms);
2439 /* Given a template argument vector containing the template PARMS.
2440 The innermost PARMS are given first. */
2443 current_template_args (void)
2446 tree args = NULL_TREE;
2447 int length = TMPL_PARMS_DEPTH (current_template_parms);
2450 /* If there is only one level of template parameters, we do not
2451 create a TREE_VEC of TREE_VECs. Instead, we return a single
2452 TREE_VEC containing the arguments. */
2454 args = make_tree_vec (length);
2456 for (header = current_template_parms; header; header = TREE_CHAIN (header))
2458 tree a = copy_node (TREE_VALUE (header));
2461 TREE_TYPE (a) = NULL_TREE;
2462 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i)
2464 tree t = TREE_VEC_ELT (a, i);
2466 /* T will be a list if we are called from within a
2467 begin/end_template_parm_list pair, but a vector directly
2468 if within a begin/end_member_template_processing pair. */
2469 if (TREE_CODE (t) == TREE_LIST)
2473 if (TREE_CODE (t) == TYPE_DECL
2474 || TREE_CODE (t) == TEMPLATE_DECL)
2477 t = DECL_INITIAL (t);
2478 TREE_VEC_ELT (a, i) = t;
2483 TREE_VEC_ELT (args, --l) = a;
2491 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated
2492 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is
2493 a member template. Used by push_template_decl below. */
2496 build_template_decl (tree decl, tree parms, bool member_template_p)
2498 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE);
2499 DECL_TEMPLATE_PARMS (tmpl) = parms;
2500 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl);
2501 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p;
2502 if (DECL_LANG_SPECIFIC (decl))
2504 DECL_STATIC_FUNCTION_P (tmpl) = DECL_STATIC_FUNCTION_P (decl);
2505 DECL_CONSTRUCTOR_P (tmpl) = DECL_CONSTRUCTOR_P (decl);
2506 DECL_DESTRUCTOR_P (tmpl) = DECL_DESTRUCTOR_P (decl);
2507 DECL_NONCONVERTING_P (tmpl) = DECL_NONCONVERTING_P (decl);
2508 DECL_ASSIGNMENT_OPERATOR_P (tmpl) = DECL_ASSIGNMENT_OPERATOR_P (decl);
2509 if (DECL_OVERLOADED_OPERATOR_P (decl))
2510 SET_OVERLOADED_OPERATOR_CODE (tmpl,
2511 DECL_OVERLOADED_OPERATOR_P (decl));
2517 struct template_parm_data
2519 /* The level of the template parameters we are currently
2523 /* The index of the specialization argument we are currently
2527 /* An array whose size is the number of template parameters. The
2528 elements are nonzero if the parameter has been used in any one
2529 of the arguments processed so far. */
2532 /* An array whose size is the number of template arguments. The
2533 elements are nonzero if the argument makes use of template
2534 parameters of this level. */
2535 int* arg_uses_template_parms;
2538 /* Subroutine of push_template_decl used to see if each template
2539 parameter in a partial specialization is used in the explicit
2540 argument list. If T is of the LEVEL given in DATA (which is
2541 treated as a template_parm_data*), then DATA->PARMS is marked
2545 mark_template_parm (tree t, void* data)
2549 struct template_parm_data* tpd = (struct template_parm_data*) data;
2551 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2553 level = TEMPLATE_PARM_LEVEL (t);
2554 idx = TEMPLATE_PARM_IDX (t);
2558 level = TEMPLATE_TYPE_LEVEL (t);
2559 idx = TEMPLATE_TYPE_IDX (t);
2562 if (level == tpd->level)
2564 tpd->parms[idx] = 1;
2565 tpd->arg_uses_template_parms[tpd->current_arg] = 1;
2568 /* Return zero so that for_each_template_parm will continue the
2569 traversal of the tree; we want to mark *every* template parm. */
2573 /* Process the partial specialization DECL. */
2576 process_partial_specialization (tree decl)
2578 tree type = TREE_TYPE (decl);
2579 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type);
2580 tree specargs = CLASSTYPE_TI_ARGS (type);
2581 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs);
2582 tree inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms);
2583 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl);
2584 int nargs = TREE_VEC_LENGTH (inner_args);
2585 int ntparms = TREE_VEC_LENGTH (inner_parms);
2587 int did_error_intro = 0;
2588 struct template_parm_data tpd;
2589 struct template_parm_data tpd2;
2591 /* We check that each of the template parameters given in the
2592 partial specialization is used in the argument list to the
2593 specialization. For example:
2595 template <class T> struct S;
2596 template <class T> struct S<T*>;
2598 The second declaration is OK because `T*' uses the template
2599 parameter T, whereas
2601 template <class T> struct S<int>;
2603 is no good. Even trickier is:
2614 The S2<T> declaration is actually invalid; it is a
2615 full-specialization. Of course,
2618 struct S2<T (*)(U)>;
2620 or some such would have been OK. */
2621 tpd.level = TMPL_PARMS_DEPTH (current_template_parms);
2622 tpd.parms = alloca (sizeof (int) * ntparms);
2623 memset (tpd.parms, 0, sizeof (int) * ntparms);
2625 tpd.arg_uses_template_parms = alloca (sizeof (int) * nargs);
2626 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs);
2627 for (i = 0; i < nargs; ++i)
2629 tpd.current_arg = i;
2630 for_each_template_parm (TREE_VEC_ELT (inner_args, i),
2631 &mark_template_parm,
2635 for (i = 0; i < ntparms; ++i)
2636 if (tpd.parms[i] == 0)
2638 /* One of the template parms was not used in the
2640 if (!did_error_intro)
2642 error ("template parameters not used in partial specialization:");
2643 did_error_intro = 1;
2646 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i)));
2649 /* [temp.class.spec]
2651 The argument list of the specialization shall not be identical to
2652 the implicit argument list of the primary template. */
2653 if (comp_template_args
2655 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE
2657 error ("partial specialization %qT does not specialize any template arguments", type);
2659 /* [temp.class.spec]
2661 A partially specialized non-type argument expression shall not
2662 involve template parameters of the partial specialization except
2663 when the argument expression is a simple identifier.
2665 The type of a template parameter corresponding to a specialized
2666 non-type argument shall not be dependent on a parameter of the
2668 gcc_assert (nargs == DECL_NTPARMS (maintmpl));
2670 for (i = 0; i < nargs; ++i)
2672 tree arg = TREE_VEC_ELT (inner_args, i);
2673 if (/* These first two lines are the `non-type' bit. */
2675 && TREE_CODE (arg) != TEMPLATE_DECL
2676 /* This next line is the `argument expression is not just a
2677 simple identifier' condition and also the `specialized
2678 non-type argument' bit. */
2679 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX)
2681 if (tpd.arg_uses_template_parms[i])
2682 error ("template argument %qE involves template parameter(s)", arg);
2685 /* Look at the corresponding template parameter,
2686 marking which template parameters its type depends
2689 TREE_TYPE (TREE_VALUE (TREE_VEC_ELT (main_inner_parms,
2694 /* We haven't yet initialized TPD2. Do so now. */
2695 tpd2.arg_uses_template_parms
2696 = alloca (sizeof (int) * nargs);
2697 /* The number of parameters here is the number in the
2698 main template, which, as checked in the assertion
2700 tpd2.parms = alloca (sizeof (int) * nargs);
2702 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl));
2705 /* Mark the template parameters. But this time, we're
2706 looking for the template parameters of the main
2707 template, not in the specialization. */
2708 tpd2.current_arg = i;
2709 tpd2.arg_uses_template_parms[i] = 0;
2710 memset (tpd2.parms, 0, sizeof (int) * nargs);
2711 for_each_template_parm (type,
2712 &mark_template_parm,
2716 if (tpd2.arg_uses_template_parms [i])
2718 /* The type depended on some template parameters.
2719 If they are fully specialized in the
2720 specialization, that's OK. */
2722 for (j = 0; j < nargs; ++j)
2723 if (tpd2.parms[j] != 0
2724 && tpd.arg_uses_template_parms [j])
2726 error ("type %qT of template argument %qE depends "
2727 "on template parameter(s)",
2737 if (retrieve_specialization (maintmpl, specargs,
2738 /*class_specializations_p=*/true))
2739 /* We've already got this specialization. */
2742 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)
2743 = tree_cons (inner_args, inner_parms,
2744 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl));
2745 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type;
2749 /* Check that a template declaration's use of default arguments is not
2750 invalid. Here, PARMS are the template parameters. IS_PRIMARY is
2751 nonzero if DECL is the thing declared by a primary template.
2752 IS_PARTIAL is nonzero if DECL is a partial specialization. */
2755 check_default_tmpl_args (tree decl, tree parms, int is_primary, int is_partial)
2758 int last_level_to_check;
2763 A default template-argument shall not be specified in a
2764 function template declaration or a function template definition, nor
2765 in the template-parameter-list of the definition of a member of a
2768 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL)
2769 /* You can't have a function template declaration in a local
2770 scope, nor you can you define a member of a class template in a
2774 if (current_class_type
2775 && !TYPE_BEING_DEFINED (current_class_type)
2776 && DECL_LANG_SPECIFIC (decl)
2777 /* If this is either a friend defined in the scope of the class
2778 or a member function. */
2779 && (DECL_FUNCTION_MEMBER_P (decl)
2780 ? same_type_p (DECL_CONTEXT (decl), current_class_type)
2781 : DECL_FRIEND_CONTEXT (decl)
2782 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type)
2784 /* And, if it was a member function, it really was defined in
2785 the scope of the class. */
2786 && (!DECL_FUNCTION_MEMBER_P (decl)
2787 || DECL_INITIALIZED_IN_CLASS_P (decl)))
2788 /* We already checked these parameters when the template was
2789 declared, so there's no need to do it again now. This function
2790 was defined in class scope, but we're processing it's body now
2791 that the class is complete. */
2796 If a template-parameter has a default template-argument, all
2797 subsequent template-parameters shall have a default
2798 template-argument supplied. */
2799 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level))
2801 tree inner_parms = TREE_VALUE (parm_level);
2802 int ntparms = TREE_VEC_LENGTH (inner_parms);
2803 int seen_def_arg_p = 0;
2806 for (i = 0; i < ntparms; ++i)
2808 tree parm = TREE_VEC_ELT (inner_parms, i);
2809 if (TREE_PURPOSE (parm))
2811 else if (seen_def_arg_p)
2813 error ("no default argument for %qD", TREE_VALUE (parm));
2814 /* For better subsequent error-recovery, we indicate that
2815 there should have been a default argument. */
2816 TREE_PURPOSE (parm) = error_mark_node;
2821 if (TREE_CODE (decl) != TYPE_DECL || is_partial || !is_primary)
2822 /* For an ordinary class template, default template arguments are
2823 allowed at the innermost level, e.g.:
2824 template <class T = int>
2826 but, in a partial specialization, they're not allowed even
2827 there, as we have in [temp.class.spec]:
2829 The template parameter list of a specialization shall not
2830 contain default template argument values.
2832 So, for a partial specialization, or for a function template,
2833 we look at all of them. */
2836 /* But, for a primary class template that is not a partial
2837 specialization we look at all template parameters except the
2839 parms = TREE_CHAIN (parms);
2841 /* Figure out what error message to issue. */
2842 if (TREE_CODE (decl) == FUNCTION_DECL)
2843 msg = "default template arguments may not be used in function templates";
2844 else if (is_partial)
2845 msg = "default template arguments may not be used in partial specializations";
2847 msg = "default argument for template parameter for class enclosing %qD";
2849 if (current_class_type && TYPE_BEING_DEFINED (current_class_type))
2850 /* If we're inside a class definition, there's no need to
2851 examine the parameters to the class itself. On the one
2852 hand, they will be checked when the class is defined, and,
2853 on the other, default arguments are valid in things like:
2854 template <class T = double>
2855 struct S { template <class U> void f(U); };
2856 Here the default argument for `S' has no bearing on the
2857 declaration of `f'. */
2858 last_level_to_check = template_class_depth (current_class_type) + 1;
2860 /* Check everything. */
2861 last_level_to_check = 0;
2863 for (parm_level = parms;
2864 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check;
2865 parm_level = TREE_CHAIN (parm_level))
2867 tree inner_parms = TREE_VALUE (parm_level);
2871 ntparms = TREE_VEC_LENGTH (inner_parms);
2872 for (i = 0; i < ntparms; ++i)
2873 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)))
2881 /* Clear out the default argument so that we are not
2883 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE;
2886 /* At this point, if we're still interested in issuing messages,
2887 they must apply to classes surrounding the object declared. */
2889 msg = "default argument for template parameter for class enclosing %qD";
2893 /* Worker for push_template_decl_real, called via
2894 for_each_template_parm. DATA is really an int, indicating the
2895 level of the parameters we are interested in. If T is a template
2896 parameter of that level, return nonzero. */
2899 template_parm_this_level_p (tree t, void* data)
2901 int this_level = *(int *)data;
2904 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX)
2905 level = TEMPLATE_PARM_LEVEL (t);
2907 level = TEMPLATE_TYPE_LEVEL (t);
2908 return level == this_level;
2911 /* Creates a TEMPLATE_DECL for the indicated DECL using the template
2912 parameters given by current_template_args, or reuses a
2913 previously existing one, if appropriate. Returns the DECL, or an
2914 equivalent one, if it is replaced via a call to duplicate_decls.
2916 If IS_FRIEND is true, DECL is a friend declaration. */
2919 push_template_decl_real (tree decl, bool is_friend)
2927 int new_template_p = 0;
2928 /* True if the template is a member template, in the sense of
2930 bool member_template_p = false;
2932 if (decl == error_mark_node)
2935 /* See if this is a partial specialization. */
2936 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl)
2937 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
2938 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)));
2940 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl))
2944 /* For a friend, we want the context of the friend function, not
2945 the type of which it is a friend. */
2946 ctx = DECL_CONTEXT (decl);
2947 else if (CP_DECL_CONTEXT (decl)
2948 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL)
2949 /* In the case of a virtual function, we want the class in which
2951 ctx = CP_DECL_CONTEXT (decl);
2953 /* Otherwise, if we're currently defining some class, the DECL
2954 is assumed to be a member of the class. */
2955 ctx = current_scope ();
2957 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL)
2960 if (!DECL_CONTEXT (decl))
2961 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
2963 /* See if this is a primary template. */
2964 primary = template_parm_scope_p ();
2968 if (DECL_CLASS_SCOPE_P (decl))
2969 member_template_p = true;
2970 if (current_lang_name == lang_name_c)
2971 error ("template with C linkage");
2972 else if (TREE_CODE (decl) == TYPE_DECL
2973 && ANON_AGGRNAME_P (DECL_NAME (decl)))
2974 error ("template class without a name");
2975 else if (TREE_CODE (decl) == FUNCTION_DECL)
2977 if (DECL_DESTRUCTOR_P (decl))
2981 A destructor shall not be a member template. */
2982 error ("destructor %qD declared as member template", decl);
2983 return error_mark_node;
2985 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl))
2986 && (!TYPE_ARG_TYPES (TREE_TYPE (decl))
2987 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node
2988 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl)))
2989 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl))))
2990 == void_list_node)))
2992 /* [basic.stc.dynamic.allocation]
2994 An allocation function can be a function
2995 template. ... Template allocation functions shall
2996 have two or more parameters. */
2997 error ("invalid template declaration of %qD", decl);
3001 else if ((DECL_IMPLICIT_TYPEDEF_P (decl)
3002 && CLASS_TYPE_P (TREE_TYPE (decl)))
3003 || (TREE_CODE (decl) == VAR_DECL && ctx && CLASS_TYPE_P (ctx)))
3007 error ("template declaration of %q#D", decl);
3008 return error_mark_node;
3012 /* Check to see that the rules regarding the use of default
3013 arguments are not being violated. */
3014 check_default_tmpl_args (decl, current_template_parms,
3015 primary, is_partial);
3018 return process_partial_specialization (decl);
3020 args = current_template_args ();
3023 || TREE_CODE (ctx) == FUNCTION_DECL
3024 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3025 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3027 if (DECL_LANG_SPECIFIC (decl)
3028 && DECL_TEMPLATE_INFO (decl)
3029 && DECL_TI_TEMPLATE (decl))
3030 tmpl = DECL_TI_TEMPLATE (decl);
3031 /* If DECL is a TYPE_DECL for a class-template, then there won't
3032 be DECL_LANG_SPECIFIC. The information equivalent to
3033 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3034 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3035 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3036 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3038 /* Since a template declaration already existed for this
3039 class-type, we must be redeclaring it here. Make sure
3040 that the redeclaration is valid. */
3041 redeclare_class_template (TREE_TYPE (decl),
3042 current_template_parms);
3043 /* We don't need to create a new TEMPLATE_DECL; just use the
3044 one we already had. */
3045 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3049 tmpl = build_template_decl (decl, current_template_parms,
3053 if (DECL_LANG_SPECIFIC (decl)
3054 && DECL_TEMPLATE_SPECIALIZATION (decl))
3056 /* A specialization of a member template of a template
3058 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3059 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3060 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3066 tree a, t, current, parms;
3069 if (TREE_CODE (decl) == TYPE_DECL)
3071 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3072 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3073 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3074 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3075 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3078 error ("%qD does not declare a template type", decl);
3082 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3084 error ("template definition of non-template %q#D", decl);
3088 tmpl = DECL_TI_TEMPLATE (decl);
3090 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3091 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3092 && DECL_TEMPLATE_SPECIALIZATION (decl)
3093 && DECL_MEMBER_TEMPLATE_P (tmpl))
3097 /* The declaration is a specialization of a member
3098 template, declared outside the class. Therefore, the
3099 innermost template arguments will be NULL, so we
3100 replace them with the arguments determined by the
3101 earlier call to check_explicit_specialization. */
3102 args = DECL_TI_ARGS (decl);
3105 = build_template_decl (decl, current_template_parms,
3107 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3108 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3109 DECL_TI_TEMPLATE (decl) = new_tmpl;
3110 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3111 DECL_TEMPLATE_INFO (new_tmpl)
3112 = tree_cons (tmpl, args, NULL_TREE);
3114 register_specialization (new_tmpl,
3115 most_general_template (tmpl),
3121 /* Make sure the template headers we got make sense. */
3123 parms = DECL_TEMPLATE_PARMS (tmpl);
3124 i = TMPL_PARMS_DEPTH (parms);
3125 if (TMPL_ARGS_DEPTH (args) != i)
3127 error ("expected %d levels of template parms for %q#D, got %d",
3128 i, decl, TMPL_ARGS_DEPTH (args));
3131 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3133 a = TMPL_ARGS_LEVEL (args, i);
3134 t = INNERMOST_TEMPLATE_PARMS (parms);
3136 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3138 if (current == decl)
3139 error ("got %d template parameters for %q#D",
3140 TREE_VEC_LENGTH (a), decl);
3142 error ("got %d template parameters for %q#T",
3143 TREE_VEC_LENGTH (a), current);
3144 error (" but %d required", TREE_VEC_LENGTH (t));
3145 return error_mark_node;
3148 /* Perhaps we should also check that the parms are used in the
3149 appropriate qualifying scopes in the declarator? */
3151 if (current == decl)
3154 current = TYPE_CONTEXT (current);
3158 DECL_TEMPLATE_RESULT (tmpl) = decl;
3159 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3161 /* Push template declarations for global functions and types. Note
3162 that we do not try to push a global template friend declared in a
3163 template class; such a thing may well depend on the template
3164 parameters of the class. */
3165 if (new_template_p && !ctx
3166 && !(is_friend && template_class_depth (current_class_type) > 0))
3168 tmpl = pushdecl_namespace_level (tmpl, is_friend);
3169 if (tmpl == error_mark_node)
3170 return error_mark_node;
3172 /* Hide template friend classes that haven't been declared yet. */
3173 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
3175 DECL_ANTICIPATED (tmpl) = 1;
3176 DECL_FRIEND_P (tmpl) = 1;
3182 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3183 if (DECL_CONV_FN_P (tmpl))
3185 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3187 /* It is a conversion operator. See if the type converted to
3188 depends on innermost template operands. */
3190 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3192 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3196 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3197 back to its most general template. If TMPL is a specialization,
3198 ARGS may only have the innermost set of arguments. Add the missing
3199 argument levels if necessary. */
3200 if (DECL_TEMPLATE_INFO (tmpl))
3201 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3203 info = tree_cons (tmpl, args, NULL_TREE);
3205 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3207 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3208 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3209 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3210 /* Don't change the name if we've already set it up. */
3211 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3212 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3214 else if (DECL_LANG_SPECIFIC (decl))
3215 DECL_TEMPLATE_INFO (decl) = info;
3217 return DECL_TEMPLATE_RESULT (tmpl);
3221 push_template_decl (tree decl)
3223 return push_template_decl_real (decl, false);
3226 /* Called when a class template TYPE is redeclared with the indicated
3227 template PARMS, e.g.:
3229 template <class T> struct S;
3230 template <class T> struct S {}; */
3233 redeclare_class_template (tree type, tree parms)
3239 if (!TYPE_TEMPLATE_INFO (type))
3241 error ("%qT is not a template type", type);
3245 tmpl = TYPE_TI_TEMPLATE (type);
3246 if (!PRIMARY_TEMPLATE_P (tmpl))
3247 /* The type is nested in some template class. Nothing to worry
3248 about here; there are no new template parameters for the nested
3254 error ("template specifiers not specified in declaration of %qD",
3259 parms = INNERMOST_TEMPLATE_PARMS (parms);
3260 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3262 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3264 error ("previous declaration %q+D", tmpl);
3265 error ("used %d template parameter(s) instead of %d",
3266 TREE_VEC_LENGTH (tmpl_parms),
3267 TREE_VEC_LENGTH (parms));
3271 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3273 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3274 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3275 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3276 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3278 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3280 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3281 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3282 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3284 error ("template parameter %q+#D", tmpl_parm);
3285 error ("redeclared here as %q#D", parm);
3289 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3291 /* We have in [temp.param]:
3293 A template-parameter may not be given default arguments
3294 by two different declarations in the same scope. */
3295 error ("redefinition of default argument for %q#D", parm);
3296 error ("%J original definition appeared here", tmpl_parm);
3300 if (parm_default != NULL_TREE)
3301 /* Update the previous template parameters (which are the ones
3302 that will really count) with the new default value. */
3303 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3304 else if (tmpl_default != NULL_TREE)
3305 /* Update the new parameters, too; they'll be used as the
3306 parameters for any members. */
3307 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3311 /* Simplify EXPR if it is a non-dependent expression. Returns the
3312 (possibly simplified) expression. */
3315 fold_non_dependent_expr (tree expr)
3317 /* If we're in a template, but EXPR isn't value dependent, simplify
3318 it. We're supposed to treat:
3320 template <typename T> void f(T[1 + 1]);
3321 template <typename T> void f(T[2]);
3323 as two declarations of the same function, for example. */
3324 if (processing_template_decl
3325 && !type_dependent_expression_p (expr)
3326 && !value_dependent_expression_p (expr))
3328 HOST_WIDE_INT saved_processing_template_decl;
3330 saved_processing_template_decl = processing_template_decl;
3331 processing_template_decl = 0;
3332 expr = tsubst_copy_and_build (expr,
3335 /*in_decl=*/NULL_TREE,
3336 /*function_p=*/false);
3337 processing_template_decl = saved_processing_template_decl;
3342 /* EXPR is an expression which is used in a constant-expression context.
3343 For instance, it could be a VAR_DECL with a constant initializer.
3344 Extract the innest constant expression.
3346 This is basically a more powerful version of
3347 integral_constant_value, which can be used also in templates where
3348 initializers can maintain a syntactic rather than semantic form
3349 (even if they are non-dependent, for access-checking purposes). */
3352 fold_decl_constant_value (tree expr)
3354 tree const_expr = expr;
3357 expr = fold_non_dependent_expr (const_expr);
3358 const_expr = integral_constant_value (expr);
3360 while (expr != const_expr);
3365 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3366 must be a function or a pointer-to-function type, as specified
3367 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3368 and check that the resulting function has external linkage. */
3371 convert_nontype_argument_function (tree type, tree expr)
3376 fn = instantiate_type (type, fns, tf_none);
3377 if (fn == error_mark_node)
3378 return error_mark_node;
3381 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3382 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3384 /* [temp.arg.nontype]/1
3386 A template-argument for a non-type, non-template template-parameter
3389 -- the address of an object or function with external linkage. */
3390 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3392 error ("%qE is not a valid template argument for type %qT "
3393 "because function %qD has not external linkage",
3394 expr, type, fn_no_ptr);
3401 /* Attempt to convert the non-type template parameter EXPR to the
3402 indicated TYPE. If the conversion is successful, return the
3403 converted value. If the conversion is unsuccessful, return
3404 NULL_TREE if we issued an error message, or error_mark_node if we
3405 did not. We issue error messages for out-and-out bad template
3406 parameters, but not simply because the conversion failed, since we
3407 might be just trying to do argument deduction. Both TYPE and EXPR
3408 must be non-dependent.
3410 The conversion follows the special rules described in
3411 [temp.arg.nontype], and it is much more strict than an implicit
3414 This function is called twice for each template argument (see
3415 lookup_template_class for a more accurate description of this
3416 problem). This means that we need to handle expressions which
3417 are not valid in a C++ source, but can be created from the
3418 first call (for instance, casts to perform conversions). These
3419 hacks can go away after we fix the double coercion problem. */
3422 convert_nontype_argument (tree type, tree expr)
3426 /* Detect immediately string literals as invalid non-type argument.
3427 This special-case is not needed for correctness (we would easily
3428 catch this later), but only to provide better diagnostic for this
3429 common user mistake. As suggested by DR 100, we do not mention
3430 linkage issues in the diagnostic as this is not the point. */
3431 if (TREE_CODE (expr) == STRING_CST)
3433 error ("%qE is not a valid template argument for type %qT "
3434 "because string literals can never be used in this context",
3439 /* If we are in a template, EXPR may be non-dependent, but still
3440 have a syntactic, rather than semantic, form. For example, EXPR
3441 might be a SCOPE_REF, rather than the VAR_DECL to which the
3442 SCOPE_REF refers. Preserving the qualifying scope is necessary
3443 so that access checking can be performed when the template is
3444 instantiated -- but here we need the resolved form so that we can
3445 convert the argument. */
3446 expr = fold_non_dependent_expr (expr);
3447 expr_type = TREE_TYPE (expr);
3449 /* HACK: Due to double coercion, we can get a
3450 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3451 which is the tree that we built on the first call (see
3452 below when coercing to reference to object or to reference to
3453 function). We just strip everything and get to the arg.
3454 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3456 if (TREE_CODE (expr) == NOP_EXPR)
3458 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3460 /* ??? Maybe we could use convert_from_reference here, but we
3461 would need to relax its constraints because the NOP_EXPR
3462 could actually change the type to something more cv-qualified,
3463 and this is not folded by convert_from_reference. */
3464 tree addr = TREE_OPERAND (expr, 0);
3465 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3466 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3467 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3468 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3469 (TREE_TYPE (expr_type),
3470 TREE_TYPE (TREE_TYPE (addr))));
3472 expr = TREE_OPERAND (addr, 0);
3473 expr_type = TREE_TYPE (expr);
3476 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3477 parameter is a pointer to object, through decay and
3478 qualification conversion. Let's strip everything. */
3479 else if (TYPE_PTROBV_P (type))
3482 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3483 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3484 /* Skip the ADDR_EXPR only if it is part of the decay for
3485 an array. Otherwise, it is part of the original argument
3486 in the source code. */
3487 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3488 expr = TREE_OPERAND (expr, 0);
3489 expr_type = TREE_TYPE (expr);
3493 /* [temp.arg.nontype]/5, bullet 1
3495 For a non-type template-parameter of integral or enumeration type,
3496 integral promotions (_conv.prom_) and integral conversions
3497 (_conv.integral_) are applied. */
3498 if (INTEGRAL_TYPE_P (type))
3500 if (!INTEGRAL_TYPE_P (expr_type))
3501 return error_mark_node;
3503 expr = fold_decl_constant_value (expr);
3504 /* Notice that there are constant expressions like '4 % 0' which
3505 do not fold into integer constants. */
3506 if (TREE_CODE (expr) != INTEGER_CST)
3508 error ("%qE is not a valid template argument for type %qT "
3509 "because it is a non-constant expression", expr, type);
3513 /* At this point, an implicit conversion does what we want,
3514 because we already know that the expression is of integral
3516 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3517 if (expr == error_mark_node)
3518 return error_mark_node;
3520 /* Conversion was allowed: fold it to a bare integer constant. */
3523 /* [temp.arg.nontype]/5, bullet 2
3525 For a non-type template-parameter of type pointer to object,
3526 qualification conversions (_conv.qual_) and the array-to-pointer
3527 conversion (_conv.array_) are applied. */
3528 else if (TYPE_PTROBV_P (type))
3530 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3532 A template-argument for a non-type, non-template template-parameter
3533 shall be one of: [...]
3535 -- the name of a non-type template-parameter;
3536 -- the address of an object or function with external linkage, [...]
3537 expressed as "& id-expression" where the & is optional if the name
3538 refers to a function or array, or if the corresponding
3539 template-parameter is a reference.
3541 Here, we do not care about functions, as they are invalid anyway
3542 for a parameter of type pointer-to-object. */
3543 bool constant_address_p =
3544 (TREE_CODE (expr) == ADDR_EXPR
3545 || TREE_CODE (expr_type) == ARRAY_TYPE
3546 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3548 expr = decay_conversion (expr);
3549 if (expr == error_mark_node)
3550 return error_mark_node;
3552 expr = perform_qualification_conversions (type, expr);
3553 if (expr == error_mark_node)
3554 return error_mark_node;
3556 if (!constant_address_p)
3558 error ("%qE is not a valid template argument for type %qT "
3559 "because it is not a constant pointer", expr, type);
3563 /* [temp.arg.nontype]/5, bullet 3
3565 For a non-type template-parameter of type reference to object, no
3566 conversions apply. The type referred to by the reference may be more
3567 cv-qualified than the (otherwise identical) type of the
3568 template-argument. The template-parameter is bound directly to the
3569 template-argument, which must be an lvalue. */
3570 else if (TYPE_REF_OBJ_P (type))
3572 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3574 return error_mark_node;
3576 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3578 error ("%qE is not a valid template argument for type %qT "
3579 "because of conflicts in cv-qualification", expr, type);
3583 if (!real_lvalue_p (expr))
3585 error ("%qE is not a valid template argument for type %qT "
3586 "because it is not a lvalue", expr, type);
3590 /* [temp.arg.nontype]/1
3592 A template-argument for a non-type, non-template template-parameter
3593 shall be one of: [...]
3595 -- the address of an object or function with external linkage. */
3596 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3598 error ("%qE is not a valid template argument for type %qT "
3599 "because object %qD has not external linkage",
3604 expr = build_nop (type, build_address (expr));
3606 /* [temp.arg.nontype]/5, bullet 4
3608 For a non-type template-parameter of type pointer to function, only
3609 the function-to-pointer conversion (_conv.func_) is applied. If the
3610 template-argument represents a set of overloaded functions (or a
3611 pointer to such), the matching function is selected from the set
3613 else if (TYPE_PTRFN_P (type))
3615 /* If the argument is a template-id, we might not have enough
3616 context information to decay the pointer. */
3617 if (!type_unknown_p (expr_type))
3619 expr = decay_conversion (expr);
3620 if (expr == error_mark_node)
3621 return error_mark_node;
3624 expr = convert_nontype_argument_function (type, expr);
3625 if (!expr || expr == error_mark_node)
3628 /* [temp.arg.nontype]/5, bullet 5
3630 For a non-type template-parameter of type reference to function, no
3631 conversions apply. If the template-argument represents a set of
3632 overloaded functions, the matching function is selected from the set
3634 else if (TYPE_REFFN_P (type))
3636 if (TREE_CODE (expr) == ADDR_EXPR)
3638 error ("%qE is not a valid template argument for type %qT "
3639 "because it is a pointer", expr, type);
3640 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3644 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3645 if (!expr || expr == error_mark_node)
3648 expr = build_nop (type, build_address (expr));
3650 /* [temp.arg.nontype]/5, bullet 6
3652 For a non-type template-parameter of type pointer to member function,
3653 no conversions apply. If the template-argument represents a set of
3654 overloaded member functions, the matching member function is selected
3655 from the set (_over.over_). */
3656 else if (TYPE_PTRMEMFUNC_P (type))
3658 expr = instantiate_type (type, expr, tf_none);
3659 if (expr == error_mark_node)
3660 return error_mark_node;
3662 /* There is no way to disable standard conversions in
3663 resolve_address_of_overloaded_function (called by
3664 instantiate_type). It is possible that the call succeeded by
3665 converting &B::I to &D::I (where B is a base of D), so we need
3666 to reject this conversion here.
3668 Actually, even if there was a way to disable standard conversions,
3669 it would still be better to reject them here so that we can
3670 provide a superior diagnostic. */
3671 if (!same_type_p (TREE_TYPE (expr), type))
3673 /* Make sure we are just one standard conversion off. */
3674 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3675 error ("%qE is not a valid template argument for type %qT "
3676 "because it is of type %qT", expr, type,
3678 inform ("standard conversions are not allowed in this context");
3682 /* [temp.arg.nontype]/5, bullet 7
3684 For a non-type template-parameter of type pointer to data member,
3685 qualification conversions (_conv.qual_) are applied. */
3686 else if (TYPE_PTRMEM_P (type))
3688 expr = perform_qualification_conversions (type, expr);
3689 if (expr == error_mark_node)
3692 /* A template non-type parameter must be one of the above. */
3696 /* Sanity check: did we actually convert the argument to the
3698 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3703 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3704 template template parameters. Both PARM_PARMS and ARG_PARMS are
3705 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3708 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3709 the case, then extra parameters must have default arguments.
3711 Consider the example:
3712 template <class T, class Allocator = allocator> class vector;
3713 template<template <class U> class TT> class C;
3715 C<vector> is a valid instantiation. PARM_PARMS for the above code
3716 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3717 T and Allocator) and OUTER_ARGS contains the argument that is used to
3718 substitute the TT parameter. */
3721 coerce_template_template_parms (tree parm_parms,
3723 tsubst_flags_t complain,
3727 int nparms, nargs, i;
3730 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3731 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3733 nparms = TREE_VEC_LENGTH (parm_parms);
3734 nargs = TREE_VEC_LENGTH (arg_parms);
3736 /* The rule here is opposite of coerce_template_parms. */
3739 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3742 for (i = 0; i < nparms; ++i)
3744 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3745 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3747 if (arg == NULL_TREE || arg == error_mark_node
3748 || parm == NULL_TREE || parm == error_mark_node)
3751 if (TREE_CODE (arg) != TREE_CODE (parm))
3754 switch (TREE_CODE (parm))
3760 /* We encounter instantiations of templates like
3761 template <template <template <class> class> class TT>
3764 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3765 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3767 if (!coerce_template_template_parms
3768 (parmparm, argparm, complain, in_decl, outer_args))
3774 /* The tsubst call is used to handle cases such as
3776 template <int> class C {};
3777 template <class T, template <T> class TT> class D {};
3780 i.e. the parameter list of TT depends on earlier parameters. */
3781 if (!dependent_type_p (TREE_TYPE (arg))
3783 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3795 /* Convert the indicated template ARG as necessary to match the
3796 indicated template PARM. Returns the converted ARG, or
3797 error_mark_node if the conversion was unsuccessful. Error and
3798 warning messages are issued under control of COMPLAIN. This
3799 conversion is for the Ith parameter in the parameter list. ARGS is
3800 the full set of template arguments deduced so far. */
3803 convert_template_argument (tree parm,
3806 tsubst_flags_t complain,
3812 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3814 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3816 if (TREE_CODE (arg) == TREE_LIST
3817 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3819 /* The template argument was the name of some
3820 member function. That's usually
3821 invalid, but static members are OK. In any
3822 case, grab the underlying fields/functions
3823 and issue an error later if required. */
3824 arg = TREE_VALUE (arg);
3825 TREE_TYPE (arg) = unknown_type_node;
3828 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3829 requires_type = (TREE_CODE (parm) == TYPE_DECL
3830 || requires_tmpl_type);
3832 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3833 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3834 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3835 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3838 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3839 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3840 arg = TYPE_STUB_DECL (arg);
3842 is_type = TYPE_P (arg) || is_tmpl_type;
3844 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3845 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3847 pedwarn ("to refer to a type member of a template parameter, "
3848 "use %<typename %E%>", arg);
3850 arg = make_typename_type (TREE_OPERAND (arg, 0),
3851 TREE_OPERAND (arg, 1),
3853 complain & tf_error);
3856 if (is_type != requires_type)
3860 if (complain & tf_error)
3862 error ("type/value mismatch at argument %d in template "
3863 "parameter list for %qD",
3866 error (" expected a constant of type %qT, got %qT",
3868 (is_tmpl_type ? DECL_NAME (arg) : arg));
3869 else if (requires_tmpl_type)
3870 error (" expected a class template, got %qE", arg);
3872 error (" expected a type, got %qE", arg);
3875 return error_mark_node;
3877 if (is_tmpl_type ^ requires_tmpl_type)
3879 if (in_decl && (complain & tf_error))
3881 error ("type/value mismatch at argument %d in template "
3882 "parameter list for %qD",
3885 error (" expected a type, got %qT", DECL_NAME (arg));
3887 error (" expected a class template, got %qT", arg);
3889 return error_mark_node;
3894 if (requires_tmpl_type)
3896 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3897 /* The number of argument required is not known yet.
3898 Just accept it for now. */
3899 val = TREE_TYPE (arg);
3902 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3903 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3905 if (coerce_template_template_parms (parmparm, argparm,
3911 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3913 if (val != error_mark_node
3914 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3915 val = TREE_TYPE (val);
3919 if (in_decl && (complain & tf_error))
3921 error ("type/value mismatch at argument %d in "
3922 "template parameter list for %qD",
3924 error (" expected a template of type %qD, got %qD",
3928 val = error_mark_node;
3937 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3939 if (invalid_nontype_parm_type_p (t, complain))
3940 return error_mark_node;
3942 if (!uses_template_parms (arg) && !uses_template_parms (t))
3943 /* We used to call digest_init here. However, digest_init
3944 will report errors, which we don't want when complain
3945 is zero. More importantly, digest_init will try too
3946 hard to convert things: for example, `0' should not be
3947 converted to pointer type at this point according to
3948 the standard. Accepting this is not merely an
3949 extension, since deciding whether or not these
3950 conversions can occur is part of determining which
3951 function template to call, or whether a given explicit
3952 argument specification is valid. */
3953 val = convert_nontype_argument (t, arg);
3957 if (val == NULL_TREE)
3958 val = error_mark_node;
3959 else if (val == error_mark_node && (complain & tf_error))
3960 error ("could not convert template argument %qE to %qT", arg, t);
3966 /* Convert all template arguments to their appropriate types, and
3967 return a vector containing the innermost resulting template
3968 arguments. If any error occurs, return error_mark_node. Error and
3969 warning messages are issued under control of COMPLAIN.
3971 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3972 provided in ARGLIST, or else trailing parameters must have default
3973 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3974 deduction for any unspecified trailing arguments. */
3977 coerce_template_parms (tree parms,
3980 tsubst_flags_t complain,
3981 int require_all_arguments)
3983 int nparms, nargs, i, lost = 0;
3986 tree new_inner_args;
3988 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3989 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3990 nparms = TREE_VEC_LENGTH (parms);
3994 && require_all_arguments
3995 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
3997 if (complain & tf_error)
3999 error ("wrong number of template arguments (%d, should be %d)",
4003 error ("provided for %q+D", in_decl);
4006 return error_mark_node;
4009 new_inner_args = make_tree_vec (nparms);
4010 new_args = add_outermost_template_args (args, new_inner_args);
4011 for (i = 0; i < nparms; i++)
4016 /* Get the Ith template parameter. */
4017 parm = TREE_VEC_ELT (parms, i);
4019 /* Calculate the Ith argument. */
4021 arg = TREE_VEC_ELT (inner_args, i);
4022 else if (require_all_arguments)
4023 /* There must be a default arg in this case. */
4024 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4030 if (arg == error_mark_node)
4032 if (complain & tf_error)
4033 error ("template argument %d is invalid", i + 1);
4036 arg = convert_template_argument (TREE_VALUE (parm),
4037 arg, new_args, complain, i,
4040 if (arg == error_mark_node)
4042 TREE_VEC_ELT (new_inner_args, i) = arg;
4046 return error_mark_node;
4048 return new_inner_args;
4051 /* Returns 1 if template args OT and NT are equivalent. */
4054 template_args_equal (tree ot, tree nt)
4059 if (TREE_CODE (nt) == TREE_VEC)
4060 /* For member templates */
4061 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4062 else if (TYPE_P (nt))
4063 return TYPE_P (ot) && same_type_p (ot, nt);
4064 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4067 return cp_tree_equal (ot, nt);
4070 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4071 of template arguments. Returns 0 otherwise. */
4074 comp_template_args (tree oldargs, tree newargs)
4078 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4081 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4083 tree nt = TREE_VEC_ELT (newargs, i);
4084 tree ot = TREE_VEC_ELT (oldargs, i);
4086 if (! template_args_equal (ot, nt))
4092 /* Given class template name and parameter list, produce a user-friendly name
4093 for the instantiation. */
4096 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4098 static struct obstack scratch_obstack;
4099 static char *scratch_firstobj;
4102 if (!scratch_firstobj)
4103 gcc_obstack_init (&scratch_obstack);
4105 obstack_free (&scratch_obstack, scratch_firstobj);
4106 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4108 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4109 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4113 nparms = TREE_VEC_LENGTH (parms);
4114 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4115 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4116 for (i = 0; i < nparms; i++)
4118 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4119 tree arg = TREE_VEC_ELT (arglist, i);
4124 if (TREE_CODE (parm) == TYPE_DECL)
4126 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4129 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4131 if (TREE_CODE (arg) == TEMPLATE_DECL)
4133 /* Already substituted with real template. Just output
4134 the template name here */
4135 tree context = DECL_CONTEXT (arg);
4138 /* The template may be defined in a namespace, or
4139 may be a member template. */
4140 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4141 || CLASS_TYPE_P (context));
4142 cat (decl_as_string (DECL_CONTEXT (arg),
4143 TFF_PLAIN_IDENTIFIER));
4146 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4149 /* Output the parameter declaration. */
4150 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4154 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4156 /* No need to check arglist against parmlist here; we did that
4157 in coerce_template_parms, called from lookup_template_class. */
4158 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4161 char *bufp = obstack_next_free (&scratch_obstack);
4163 while (bufp[offset - 1] == ' ')
4165 obstack_blank_fast (&scratch_obstack, offset);
4167 /* B<C<char> >, not B<C<char>> */
4168 if (bufp[offset - 1] == '>')
4173 return (char *) obstack_base (&scratch_obstack);
4177 classtype_mangled_name (tree t)
4179 if (CLASSTYPE_TEMPLATE_INFO (t)
4180 /* Specializations have already had their names set up in
4181 lookup_template_class. */
4182 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4184 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4186 /* For non-primary templates, the template parameters are
4187 implicit from their surrounding context. */
4188 if (PRIMARY_TEMPLATE_P (tmpl))
4190 tree name = DECL_NAME (tmpl);
4191 char *mangled_name = mangle_class_name_for_template
4192 (IDENTIFIER_POINTER (name),
4193 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4194 CLASSTYPE_TI_ARGS (t));
4195 tree id = get_identifier (mangled_name);
4196 IDENTIFIER_TEMPLATE (id) = name;
4201 return TYPE_IDENTIFIER (t);
4205 add_pending_template (tree d)
4207 tree ti = (TYPE_P (d)
4208 ? CLASSTYPE_TEMPLATE_INFO (d)
4209 : DECL_TEMPLATE_INFO (d));
4213 if (TI_PENDING_TEMPLATE_FLAG (ti))
4216 /* We are called both from instantiate_decl, where we've already had a
4217 tinst_level pushed, and instantiate_template, where we haven't.
4219 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4222 push_tinst_level (d);
4224 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4225 if (last_pending_template)
4226 TREE_CHAIN (last_pending_template) = pt;
4228 pending_templates = pt;
4230 last_pending_template = pt;
4232 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4239 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4240 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4241 documentation for TEMPLATE_ID_EXPR. */
4244 lookup_template_function (tree fns, tree arglist)
4248 if (fns == error_mark_node || arglist == error_mark_node)
4249 return error_mark_node;
4251 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4252 gcc_assert (fns && (is_overloaded_fn (fns)
4253 || TREE_CODE (fns) == IDENTIFIER_NODE));
4255 if (BASELINK_P (fns))
4257 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4259 BASELINK_FUNCTIONS (fns),
4264 type = TREE_TYPE (fns);
4265 if (TREE_CODE (fns) == OVERLOAD || !type)
4266 type = unknown_type_node;
4268 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4271 /* Within the scope of a template class S<T>, the name S gets bound
4272 (in build_self_reference) to a TYPE_DECL for the class, not a
4273 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4274 or one of its enclosing classes, and that type is a template,
4275 return the associated TEMPLATE_DECL. Otherwise, the original
4276 DECL is returned. */
4279 maybe_get_template_decl_from_type_decl (tree decl)
4281 return (decl != NULL_TREE
4282 && TREE_CODE (decl) == TYPE_DECL
4283 && DECL_ARTIFICIAL (decl)
4284 && CLASS_TYPE_P (TREE_TYPE (decl))
4285 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4286 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4289 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4290 parameters, find the desired type.
4292 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4294 IN_DECL, if non-NULL, is the template declaration we are trying to
4297 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4298 the class we are looking up.
4300 Issue error and warning messages under control of COMPLAIN.
4302 If the template class is really a local class in a template
4303 function, then the FUNCTION_CONTEXT is the function in which it is
4306 ??? Note that this function is currently called *twice* for each
4307 template-id: the first time from the parser, while creating the
4308 incomplete type (finish_template_type), and the second type during the
4309 real instantiation (instantiate_template_class). This is surely something
4310 that we want to avoid. It also causes some problems with argument
4311 coercion (see convert_nontype_argument for more information on this). */
4314 lookup_template_class (tree d1,
4319 tsubst_flags_t complain)
4321 tree template = NULL_TREE, parmlist;
4324 timevar_push (TV_NAME_LOOKUP);
4326 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4328 tree value = innermost_non_namespace_value (d1);
4329 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4334 push_decl_namespace (context);
4335 template = lookup_name (d1, /*prefer_type=*/0);
4336 template = maybe_get_template_decl_from_type_decl (template);
4338 pop_decl_namespace ();
4341 context = DECL_CONTEXT (template);
4343 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4345 tree type = TREE_TYPE (d1);
4347 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4348 an implicit typename for the second A. Deal with it. */
4349 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4350 type = TREE_TYPE (type);
4352 if (CLASSTYPE_TEMPLATE_INFO (type))
4354 template = CLASSTYPE_TI_TEMPLATE (type);
4355 d1 = DECL_NAME (template);
4358 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4359 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4361 template = TYPE_TI_TEMPLATE (d1);
4362 d1 = DECL_NAME (template);
4364 else if (TREE_CODE (d1) == TEMPLATE_DECL
4365 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4368 d1 = DECL_NAME (template);
4369 context = DECL_CONTEXT (template);
4372 /* Issue an error message if we didn't find a template. */
4375 if (complain & tf_error)
4376 error ("%qT is not a template", d1);
4377 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4380 if (TREE_CODE (template) != TEMPLATE_DECL
4381 /* Make sure it's a user visible template, if it was named by
4383 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4384 && !PRIMARY_TEMPLATE_P (template)))
4386 if (complain & tf_error)
4388 error ("non-template type %qT used as a template", d1);
4390 error ("for template declaration %q+D", in_decl);
4392 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4395 complain &= ~tf_user;
4397 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4399 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4400 template arguments */
4405 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4407 /* Consider an example where a template template parameter declared as
4409 template <class T, class U = std::allocator<T> > class TT
4411 The template parameter level of T and U are one level larger than
4412 of TT. To proper process the default argument of U, say when an
4413 instantiation `TT<int>' is seen, we need to build the full
4414 arguments containing {int} as the innermost level. Outer levels,
4415 available when not appearing as default template argument, can be
4416 obtained from `current_template_args ()'.
4418 Suppose that TT is later substituted with std::vector. The above
4419 instantiation is `TT<int, std::allocator<T> >' with TT at
4420 level 1, and T at level 2, while the template arguments at level 1
4421 becomes {std::vector} and the inner level 2 is {int}. */
4423 if (current_template_parms)
4424 arglist = add_to_template_args (current_template_args (), arglist);
4426 arglist2 = coerce_template_parms (parmlist, arglist, template,
4427 complain, /*require_all_args=*/1);
4428 if (arglist2 == error_mark_node
4429 || (!uses_template_parms (arglist2)
4430 && check_instantiated_args (template, arglist2, complain)))
4431 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4433 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4434 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4438 tree template_type = TREE_TYPE (template);
4441 tree found = NULL_TREE;
4444 int is_partial_instantiation;
4446 gen_tmpl = most_general_template (template);
4447 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4448 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4449 arg_depth = TMPL_ARGS_DEPTH (arglist);
4451 if (arg_depth == 1 && parm_depth > 1)
4453 /* We've been given an incomplete set of template arguments.
4456 template <class T> struct S1 {
4457 template <class U> struct S2 {};
4458 template <class U> struct S2<U*> {};
4461 we will be called with an ARGLIST of `U*', but the
4462 TEMPLATE will be `template <class T> template
4463 <class U> struct S1<T>::S2'. We must fill in the missing
4466 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4468 arg_depth = TMPL_ARGS_DEPTH (arglist);
4471 /* Now we should have enough arguments. */
4472 gcc_assert (parm_depth == arg_depth);
4474 /* From here on, we're only interested in the most general
4476 template = gen_tmpl;
4478 /* Calculate the BOUND_ARGS. These will be the args that are
4479 actually tsubst'd into the definition to create the
4483 /* We have multiple levels of arguments to coerce, at once. */
4485 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4487 tree bound_args = make_tree_vec (parm_depth);
4489 for (i = saved_depth,
4490 t = DECL_TEMPLATE_PARMS (template);
4491 i > 0 && t != NULL_TREE;
4492 --i, t = TREE_CHAIN (t))
4494 tree a = coerce_template_parms (TREE_VALUE (t),
4496 complain, /*require_all_args=*/1);
4498 /* Don't process further if one of the levels fails. */
4499 if (a == error_mark_node)
4501 /* Restore the ARGLIST to its full size. */
4502 TREE_VEC_LENGTH (arglist) = saved_depth;
4503 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4506 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4508 /* We temporarily reduce the length of the ARGLIST so
4509 that coerce_template_parms will see only the arguments
4510 corresponding to the template parameters it is
4512 TREE_VEC_LENGTH (arglist)--;
4515 /* Restore the ARGLIST to its full size. */
4516 TREE_VEC_LENGTH (arglist) = saved_depth;
4518 arglist = bound_args;
4522 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4523 INNERMOST_TEMPLATE_ARGS (arglist),
4525 complain, /*require_all_args=*/1);
4527 if (arglist == error_mark_node)
4528 /* We were unable to bind the arguments. */
4529 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4531 /* In the scope of a template class, explicit references to the
4532 template class refer to the type of the template, not any
4533 instantiation of it. For example, in:
4535 template <class T> class C { void f(C<T>); }
4537 the `C<T>' is just the same as `C'. Outside of the
4538 class, however, such a reference is an instantiation. */
4539 if (comp_template_args (TYPE_TI_ARGS (template_type),
4542 found = template_type;
4544 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4548 for (ctx = current_class_type;
4549 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4551 ? TYPE_CONTEXT (ctx)
4552 : DECL_CONTEXT (ctx)))
4553 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4556 /* We're not in the scope of the class, so the
4557 TEMPLATE_TYPE is not the type we want after all. */
4563 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4565 /* If we already have this specialization, return it. */
4566 found = retrieve_specialization (template, arglist,
4567 /*class_specializations_p=*/false);
4569 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4571 /* This type is a "partial instantiation" if any of the template
4572 arguments still involve template parameters. Note that we set
4573 IS_PARTIAL_INSTANTIATION for partial specializations as
4575 is_partial_instantiation = uses_template_parms (arglist);
4577 /* If the deduced arguments are invalid, then the binding
4579 if (!is_partial_instantiation
4580 && check_instantiated_args (template,
4581 INNERMOST_TEMPLATE_ARGS (arglist),
4583 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4585 if (!is_partial_instantiation
4586 && !PRIMARY_TEMPLATE_P (template)
4587 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4589 found = xref_tag_from_type (TREE_TYPE (template),
4590 DECL_NAME (template),
4591 /*tag_scope=*/ts_global);
4592 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4595 context = tsubst (DECL_CONTEXT (template), arglist,
4598 context = global_namespace;
4600 /* Create the type. */
4601 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4603 if (!is_partial_instantiation)
4605 set_current_access_from_decl (TYPE_NAME (template_type));
4606 t = start_enum (TYPE_IDENTIFIER (template_type));
4609 /* We don't want to call start_enum for this type, since
4610 the values for the enumeration constants may involve
4611 template parameters. And, no one should be interested
4612 in the enumeration constants for such a type. */
4613 t = make_node (ENUMERAL_TYPE);
4617 t = make_aggr_type (TREE_CODE (template_type));
4618 CLASSTYPE_DECLARED_CLASS (t)
4619 = CLASSTYPE_DECLARED_CLASS (template_type);
4620 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4621 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4623 /* A local class. Make sure the decl gets registered properly. */
4624 if (context == current_function_decl)
4625 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
4628 /* If we called start_enum or pushtag above, this information
4629 will already be set up. */
4632 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4634 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4635 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4636 TYPE_STUB_DECL (t) = type_decl;
4637 DECL_SOURCE_LOCATION (type_decl)
4638 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4641 type_decl = TYPE_NAME (t);
4643 TREE_PRIVATE (type_decl)
4644 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4645 TREE_PROTECTED (type_decl)
4646 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4647 DECL_IN_SYSTEM_HEADER (type_decl)
4648 = DECL_IN_SYSTEM_HEADER (template);
4649 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
4651 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
4652 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
4655 /* Set up the template information. We have to figure out which
4656 template is the immediate parent if this is a full
4658 if (parm_depth == 1 || is_partial_instantiation
4659 || !PRIMARY_TEMPLATE_P (template))
4660 /* This case is easy; there are no member templates involved. */
4664 /* This is a full instantiation of a member template. Look
4665 for a partial instantiation of which this is an instance. */
4667 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4668 found; found = TREE_CHAIN (found))
4671 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4673 /* We only want partial instantiations, here, not
4674 specializations or full instantiations. */
4675 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4676 || !uses_template_parms (TREE_VALUE (found)))
4679 /* Temporarily reduce by one the number of levels in the
4680 ARGLIST and in FOUND so as to avoid comparing the
4681 last set of arguments. */
4682 TREE_VEC_LENGTH (arglist)--;
4683 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4685 /* See if the arguments match. If they do, then TMPL is
4686 the partial instantiation we want. */
4687 success = comp_template_args (TREE_PURPOSE (found), arglist);
4689 /* Restore the argument vectors to their full size. */
4690 TREE_VEC_LENGTH (arglist)++;
4691 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4702 /* There was no partial instantiation. This happens
4703 where C<T> is a member template of A<T> and it's used
4706 template <typename T> struct B { A<T>::C<int> m; };
4709 Create the partial instantiation.
4711 TREE_VEC_LENGTH (arglist)--;
4712 found = tsubst (template, arglist, complain, NULL_TREE);
4713 TREE_VEC_LENGTH (arglist)++;
4717 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4718 DECL_TEMPLATE_INSTANTIATIONS (template)
4719 = tree_cons (arglist, t,
4720 DECL_TEMPLATE_INSTANTIATIONS (template));
4722 if (TREE_CODE (t) == ENUMERAL_TYPE
4723 && !is_partial_instantiation)
4724 /* Now that the type has been registered on the instantiations
4725 list, we set up the enumerators. Because the enumeration
4726 constants may involve the enumeration type itself, we make
4727 sure to register the type first, and then create the
4728 constants. That way, doing tsubst_expr for the enumeration
4729 constants won't result in recursive calls here; we'll find
4730 the instantiation and exit above. */
4731 tsubst_enum (template_type, t, arglist);
4733 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4735 if (TREE_CODE (t) != ENUMERAL_TYPE)
4736 DECL_NAME (type_decl) = classtype_mangled_name (t);
4737 if (is_partial_instantiation)
4738 /* If the type makes use of template parameters, the
4739 code that generates debugging information will crash. */
4740 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4742 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4744 timevar_pop (TV_NAME_LOOKUP);
4751 struct pointer_set_t *visited;
4754 /* Called from for_each_template_parm via walk_tree. */
4757 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4760 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4761 tree_fn_t fn = pfd->fn;
4762 void *data = pfd->data;
4765 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4766 return error_mark_node;
4768 switch (TREE_CODE (t))
4771 if (TYPE_PTRMEMFUNC_P (t))
4777 if (!TYPE_TEMPLATE_INFO (t))
4779 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4780 fn, data, pfd->visited))
4781 return error_mark_node;
4785 /* Since we're not going to walk subtrees, we have to do this
4787 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4789 return error_mark_node;
4793 /* Check the return type. */
4794 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4795 return error_mark_node;
4797 /* Check the parameter types. Since default arguments are not
4798 instantiated until they are needed, the TYPE_ARG_TYPES may
4799 contain expressions that involve template parameters. But,
4800 no-one should be looking at them yet. And, once they're
4801 instantiated, they don't contain template parameters, so
4802 there's no point in looking at them then, either. */
4806 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4807 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4809 return error_mark_node;
4811 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4812 want walk_tree walking into them itself. */
4818 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4820 return error_mark_node;
4825 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4826 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4828 return error_mark_node;
4833 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4834 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4836 return error_mark_node;
4837 if (DECL_CONTEXT (t)
4838 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4840 return error_mark_node;
4843 case BOUND_TEMPLATE_TEMPLATE_PARM:
4844 /* Record template parameters such as `T' inside `TT<T>'. */
4845 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4846 return error_mark_node;
4849 case TEMPLATE_TEMPLATE_PARM:
4850 case TEMPLATE_TYPE_PARM:
4851 case TEMPLATE_PARM_INDEX:
4852 if (fn && (*fn)(t, data))
4853 return error_mark_node;
4855 return error_mark_node;
4859 /* A template template parameter is encountered. */
4860 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4861 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4862 return error_mark_node;
4864 /* Already substituted template template parameter */
4870 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4871 data, pfd->visited))
4872 return error_mark_node;
4876 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4877 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4878 (TREE_TYPE (t)), fn, data,
4880 return error_mark_node;
4885 /* If there's no type, then this thing must be some expression
4886 involving template parameters. */
4887 if (!fn && !TREE_TYPE (t))
4888 return error_mark_node;
4893 case REINTERPRET_CAST_EXPR:
4894 case CONST_CAST_EXPR:
4895 case STATIC_CAST_EXPR:
4896 case DYNAMIC_CAST_EXPR:
4900 case PSEUDO_DTOR_EXPR:
4902 return error_mark_node;
4906 /* If we do not handle this case specially, we end up walking
4907 the BINFO hierarchy, which is circular, and therefore
4908 confuses walk_tree. */
4910 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4912 return error_mark_node;
4919 /* We didn't find any template parameters we liked. */
4923 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4924 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4925 call FN with the parameter and the DATA.
4926 If FN returns nonzero, the iteration is terminated, and
4927 for_each_template_parm returns 1. Otherwise, the iteration
4928 continues. If FN never returns a nonzero value, the value
4929 returned by for_each_template_parm is 0. If FN is NULL, it is
4930 considered to be the function which always returns 1. */
4933 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4934 struct pointer_set_t *visited)
4936 struct pair_fn_data pfd;
4943 /* Walk the tree. (Conceptually, we would like to walk without
4944 duplicates, but for_each_template_parm_r recursively calls
4945 for_each_template_parm, so we would need to reorganize a fair
4946 bit to use walk_tree_without_duplicates, so we keep our own
4949 pfd.visited = visited;
4951 pfd.visited = pointer_set_create ();
4952 result = walk_tree (&t,
4953 for_each_template_parm_r,
4955 pfd.visited) != NULL_TREE;
4960 pointer_set_destroy (pfd.visited);
4967 /* Returns true if T depends on any template parameter. */
4970 uses_template_parms (tree t)
4973 int saved_processing_template_decl;
4975 saved_processing_template_decl = processing_template_decl;
4976 if (!saved_processing_template_decl)
4977 processing_template_decl = 1;
4979 dependent_p = dependent_type_p (t);
4980 else if (TREE_CODE (t) == TREE_VEC)
4981 dependent_p = any_dependent_template_arguments_p (t);
4982 else if (TREE_CODE (t) == TREE_LIST)
4983 dependent_p = (uses_template_parms (TREE_VALUE (t))
4984 || uses_template_parms (TREE_CHAIN (t)));
4987 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4988 || TREE_CODE (t) == OVERLOAD
4989 || TREE_CODE (t) == BASELINK
4990 || TREE_CODE (t) == IDENTIFIER_NODE
4991 || CONSTANT_CLASS_P (t))
4992 dependent_p = (type_dependent_expression_p (t)
4993 || value_dependent_expression_p (t));
4996 gcc_assert (t == error_mark_node);
4997 dependent_p = false;
5000 processing_template_decl = saved_processing_template_decl;
5005 /* Returns true if T depends on any template parameter with level LEVEL. */
5008 uses_template_parms_level (tree t, int level)
5010 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
5013 static int tinst_depth;
5014 extern int max_tinst_depth;
5015 #ifdef GATHER_STATISTICS
5018 static int tinst_level_tick;
5019 static int last_template_error_tick;
5021 /* We're starting to instantiate D; record the template instantiation context
5022 for diagnostics and to restore it later. */
5025 push_tinst_level (tree d)
5029 if (tinst_depth >= max_tinst_depth)
5031 /* If the instantiation in question still has unbound template parms,
5032 we don't really care if we can't instantiate it, so just return.
5033 This happens with base instantiation for implicit `typename'. */
5034 if (uses_template_parms (d))
5037 last_template_error_tick = tinst_level_tick;
5038 error ("template instantiation depth exceeds maximum of %d (use "
5039 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5040 max_tinst_depth, d);
5042 print_instantiation_context ();
5047 new = make_node (TINST_LEVEL);
5048 TINST_DECL (new) = d;
5049 TINST_LOCATION (new) = input_location;
5050 TINST_IN_SYSTEM_HEADER_P (new) = in_system_header;
5051 TREE_CHAIN (new) = current_tinst_level;
5052 current_tinst_level = new;
5055 #ifdef GATHER_STATISTICS
5056 if (tinst_depth > depth_reached)
5057 depth_reached = tinst_depth;
5064 /* We're done instantiating this template; return to the instantiation
5068 pop_tinst_level (void)
5070 tree old = current_tinst_level;
5072 /* Restore the filename and line number stashed away when we started
5073 this instantiation. */
5074 input_location = TINST_LOCATION (old);
5075 in_system_header = TINST_IN_SYSTEM_HEADER_P (old);
5076 current_tinst_level = TREE_CHAIN (old);
5081 /* We're instantiating a deferred template; restore the template
5082 instantiation context in which the instantiation was requested, which
5083 is one step out from LEVEL. */
5086 reopen_tinst_level (tree level)
5091 for (t = level; t; t = TREE_CHAIN (t))
5094 current_tinst_level = level;
5098 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5099 vector of template arguments, as for tsubst.
5101 Returns an appropriate tsubst'd friend declaration. */
5104 tsubst_friend_function (tree decl, tree args)
5108 if (TREE_CODE (decl) == FUNCTION_DECL
5109 && DECL_TEMPLATE_INSTANTIATION (decl)
5110 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5111 /* This was a friend declared with an explicit template
5112 argument list, e.g.:
5116 to indicate that f was a template instantiation, not a new
5117 function declaration. Now, we have to figure out what
5118 instantiation of what template. */
5120 tree template_id, arglist, fns;
5123 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5125 /* Friend functions are looked up in the containing namespace scope.
5126 We must enter that scope, to avoid finding member functions of the
5127 current cless with same name. */
5128 push_nested_namespace (ns);
5129 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5130 tf_error | tf_warning, NULL_TREE);
5131 pop_nested_namespace (ns);
5132 arglist = tsubst (DECL_TI_ARGS (decl), args,
5133 tf_error | tf_warning, NULL_TREE);
5134 template_id = lookup_template_function (fns, arglist);
5136 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5137 tmpl = determine_specialization (template_id, new_friend,
5139 /*need_member_template=*/0,
5140 TREE_VEC_LENGTH (args));
5141 return instantiate_template (tmpl, new_args, tf_error);
5144 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5146 /* The NEW_FRIEND will look like an instantiation, to the
5147 compiler, but is not an instantiation from the point of view of
5148 the language. For example, we might have had:
5150 template <class T> struct S {
5151 template <class U> friend void f(T, U);
5154 Then, in S<int>, template <class U> void f(int, U) is not an
5155 instantiation of anything. */
5156 if (new_friend == error_mark_node)
5157 return error_mark_node;
5159 DECL_USE_TEMPLATE (new_friend) = 0;
5160 if (TREE_CODE (decl) == TEMPLATE_DECL)
5162 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5163 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5164 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5167 /* The mangled name for the NEW_FRIEND is incorrect. The function
5168 is not a template instantiation and should not be mangled like
5169 one. Therefore, we forget the mangling here; we'll recompute it
5170 later if we need it. */
5171 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5173 SET_DECL_RTL (new_friend, NULL_RTX);
5174 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5177 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5180 tree new_friend_template_info;
5181 tree new_friend_result_template_info;
5183 int new_friend_is_defn;
5185 /* We must save some information from NEW_FRIEND before calling
5186 duplicate decls since that function will free NEW_FRIEND if
5188 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5189 new_friend_is_defn =
5190 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5191 (template_for_substitution (new_friend)))
5193 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5195 /* This declaration is a `primary' template. */
5196 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5198 new_friend_result_template_info
5199 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5202 new_friend_result_template_info = NULL_TREE;
5204 /* Inside pushdecl_namespace_level, we will push into the
5205 current namespace. However, the friend function should go
5206 into the namespace of the template. */
5207 ns = decl_namespace_context (new_friend);
5208 push_nested_namespace (ns);
5209 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
5210 pop_nested_namespace (ns);
5212 if (old_decl != new_friend)
5214 /* This new friend declaration matched an existing
5215 declaration. For example, given:
5217 template <class T> void f(T);
5218 template <class U> class C {
5219 template <class T> friend void f(T) {}
5222 the friend declaration actually provides the definition
5223 of `f', once C has been instantiated for some type. So,
5224 old_decl will be the out-of-class template declaration,
5225 while new_friend is the in-class definition.
5227 But, if `f' was called before this point, the
5228 instantiation of `f' will have DECL_TI_ARGS corresponding
5229 to `T' but not to `U', references to which might appear
5230 in the definition of `f'. Previously, the most general
5231 template for an instantiation of `f' was the out-of-class
5232 version; now it is the in-class version. Therefore, we
5233 run through all specialization of `f', adding to their
5234 DECL_TI_ARGS appropriately. In particular, they need a
5235 new set of outer arguments, corresponding to the
5236 arguments for this class instantiation.
5238 The same situation can arise with something like this:
5241 template <class T> class C {
5245 when `C<int>' is instantiated. Now, `f(int)' is defined
5248 if (!new_friend_is_defn)
5249 /* On the other hand, if the in-class declaration does
5250 *not* provide a definition, then we don't want to alter
5251 existing definitions. We can just leave everything
5256 /* Overwrite whatever template info was there before, if
5257 any, with the new template information pertaining to
5259 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5261 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5262 reregister_specialization (new_friend,
5263 most_general_template (old_decl),
5268 tree new_friend_args;
5270 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5271 = new_friend_result_template_info;
5273 new_friend_args = TI_ARGS (new_friend_template_info);
5274 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5278 tree spec = TREE_VALUE (t);
5281 = add_outermost_template_args (new_friend_args,
5282 DECL_TI_ARGS (spec));
5285 /* Now, since specializations are always supposed to
5286 hang off of the most general template, we must move
5288 t = most_general_template (old_decl);
5291 DECL_TEMPLATE_SPECIALIZATIONS (t)
5292 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5293 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5294 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5299 /* The information from NEW_FRIEND has been merged into OLD_DECL
5300 by duplicate_decls. */
5301 new_friend = old_decl;
5306 tree context = DECL_CONTEXT (new_friend);
5310 template <class T> class C {
5311 template <class U> friend void C1<U>::f (); // case 1
5312 friend void C2<T>::f (); // case 2
5314 we only need to make sure CONTEXT is a complete type for
5315 case 2. To distinguish between the two cases, we note that
5316 CONTEXT of case 1 remains dependent type after tsubst while
5317 this isn't true for case 2. */
5318 ++processing_template_decl;
5319 dependent_p = dependent_type_p (context);
5320 --processing_template_decl;
5323 && !complete_type_or_else (context, NULL_TREE))
5324 return error_mark_node;
5326 if (COMPLETE_TYPE_P (context))
5328 /* Check to see that the declaration is really present, and,
5329 possibly obtain an improved declaration. */
5330 tree fn = check_classfn (context,
5331 new_friend, NULL_TREE);
5341 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5342 template arguments, as for tsubst.
5344 Returns an appropriate tsubst'd friend type or error_mark_node on
5348 tsubst_friend_class (tree friend_tmpl, tree args)
5354 context = DECL_CONTEXT (friend_tmpl);
5358 if (TREE_CODE (context) == NAMESPACE_DECL)
5359 push_nested_namespace (context);
5361 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5364 /* First, we look for a class template. */
5365 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5367 /* But, if we don't find one, it might be because we're in a
5368 situation like this:
5376 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5377 for `S<int>', not the TEMPLATE_DECL. */
5378 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5380 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5381 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5384 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5386 /* The friend template has already been declared. Just
5387 check to see that the declarations match, and install any new
5388 default parameters. We must tsubst the default parameters,
5389 of course. We only need the innermost template parameters
5390 because that is all that redeclare_class_template will look
5392 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5393 > TMPL_ARGS_DEPTH (args))
5396 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5397 args, tf_error | tf_warning);
5398 redeclare_class_template (TREE_TYPE (tmpl), parms);
5401 friend_type = TREE_TYPE (tmpl);
5405 /* The friend template has not already been declared. In this
5406 case, the instantiation of the template class will cause the
5407 injection of this template into the global scope. */
5408 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5410 /* The new TMPL is not an instantiation of anything, so we
5411 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5412 the new type because that is supposed to be the corresponding
5413 template decl, i.e., TMPL. */
5414 DECL_USE_TEMPLATE (tmpl) = 0;
5415 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5416 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5417 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5418 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5420 /* Inject this template into the global scope. */
5421 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
5426 if (TREE_CODE (context) == NAMESPACE_DECL)
5427 pop_nested_namespace (context);
5429 pop_nested_class ();
5435 /* Returns zero if TYPE cannot be completed later due to circularity.
5436 Otherwise returns one. */
5439 can_complete_type_without_circularity (tree type)
5441 if (type == NULL_TREE || type == error_mark_node)
5443 else if (COMPLETE_TYPE_P (type))
5445 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5446 return can_complete_type_without_circularity (TREE_TYPE (type));
5447 else if (CLASS_TYPE_P (type)
5448 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5455 instantiate_class_template (tree type)
5457 tree template, args, pattern, t, member;
5462 if (type == error_mark_node)
5463 return error_mark_node;
5465 if (TYPE_BEING_DEFINED (type)
5466 || COMPLETE_TYPE_P (type)
5467 || dependent_type_p (type))
5470 /* Figure out which template is being instantiated. */
5471 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5472 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5474 /* Figure out which arguments are being used to do the
5476 args = CLASSTYPE_TI_ARGS (type);
5478 /* Determine what specialization of the original template to
5480 t = most_specialized_class (template, args);
5481 if (t == error_mark_node)
5483 const char *str = "candidates are:";
5484 error ("ambiguous class template instantiation for %q#T", type);
5485 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5488 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5490 error ("%s %+#T", str, TREE_TYPE (t));
5494 TYPE_BEING_DEFINED (type) = 1;
5495 return error_mark_node;
5499 pattern = TREE_TYPE (t);
5501 pattern = TREE_TYPE (template);
5503 /* If the template we're instantiating is incomplete, then clearly
5504 there's nothing we can do. */
5505 if (!COMPLETE_TYPE_P (pattern))
5508 /* If we've recursively instantiated too many templates, stop. */
5509 if (! push_tinst_level (type))
5512 /* Now we're really doing the instantiation. Mark the type as in
5513 the process of being defined. */
5514 TYPE_BEING_DEFINED (type) = 1;
5516 /* We may be in the middle of deferred access check. Disable
5518 push_deferring_access_checks (dk_no_deferred);
5520 push_to_top_level ();
5524 /* This TYPE is actually an instantiation of a partial
5525 specialization. We replace the innermost set of ARGS with
5526 the arguments appropriate for substitution. For example,
5529 template <class T> struct S {};
5530 template <class T> struct S<T*> {};
5532 and supposing that we are instantiating S<int*>, ARGS will
5533 present be {int*} but we need {int}. */
5535 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5538 /* If there were multiple levels in ARGS, replacing the
5539 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5540 want, so we make a copy first. */
5541 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5543 args = copy_node (args);
5544 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5550 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5552 /* Set the input location to the template definition. This is needed
5553 if tsubsting causes an error. */
5554 typedecl = TYPE_MAIN_DECL (type);
5555 input_location = DECL_SOURCE_LOCATION (typedecl);
5556 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
5558 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5559 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5560 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5561 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5562 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5563 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5564 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5565 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5566 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5567 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5568 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5569 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5570 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5571 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5572 if (ANON_AGGR_TYPE_P (pattern))
5573 SET_ANON_AGGR_TYPE_P (type);
5574 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
5576 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
5577 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
5580 pbinfo = TYPE_BINFO (pattern);
5582 /* We should never instantiate a nested class before its enclosing
5583 class; we need to look up the nested class by name before we can
5584 instantiate it, and that lookup should instantiate the enclosing
5586 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5587 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5588 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5590 base_list = NULL_TREE;
5591 if (BINFO_N_BASE_BINFOS (pbinfo))
5594 tree context = TYPE_CONTEXT (type);
5598 /* We must enter the scope containing the type, as that is where
5599 the accessibility of types named in dependent bases are
5601 pushed_scope = push_scope (context ? context : global_namespace);
5603 /* Substitute into each of the bases to determine the actual
5605 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5608 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5610 /* Substitute to figure out the base class. */
5611 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5612 if (base == error_mark_node)
5615 base_list = tree_cons (access, base, base_list);
5616 if (BINFO_VIRTUAL_P (pbase_binfo))
5617 TREE_TYPE (base_list) = integer_type_node;
5620 /* The list is now in reverse order; correct that. */
5621 base_list = nreverse (base_list);
5624 pop_scope (pushed_scope);
5626 /* Now call xref_basetypes to set up all the base-class
5628 xref_basetypes (type, base_list);
5631 /* Now that our base classes are set up, enter the scope of the
5632 class, so that name lookups into base classes, etc. will work
5633 correctly. This is precisely analogous to what we do in
5634 begin_class_definition when defining an ordinary non-template
5638 /* Now members are processed in the order of declaration. */
5639 for (member = CLASSTYPE_DECL_LIST (pattern);
5640 member; member = TREE_CHAIN (member))
5642 tree t = TREE_VALUE (member);
5644 if (TREE_PURPOSE (member))
5648 /* Build new CLASSTYPE_NESTED_UTDS. */
5651 tree name = TYPE_IDENTIFIER (tag);
5653 bool class_template_p;
5655 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5656 && TYPE_LANG_SPECIFIC (tag)
5657 && CLASSTYPE_IS_TEMPLATE (tag));
5658 /* If the member is a class template, then -- even after
5659 substitution -- there may be dependent types in the
5660 template argument list for the class. We increment
5661 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5662 that function will assume that no types are dependent
5663 when outside of a template. */
5664 if (class_template_p)
5665 ++processing_template_decl;
5666 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5667 if (class_template_p)
5668 --processing_template_decl;
5669 if (newtag == error_mark_node)
5672 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5674 if (class_template_p)
5675 /* Unfortunately, lookup_template_class sets
5676 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5677 instantiation (i.e., for the type of a member
5678 template class nested within a template class.)
5679 This behavior is required for
5680 maybe_process_partial_specialization to work
5681 correctly, but is not accurate in this case;
5682 the TAG is not an instantiation of anything.
5683 (The corresponding TEMPLATE_DECL is an
5684 instantiation, but the TYPE is not.) */
5685 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5687 /* Now, we call pushtag to put this NEWTAG into the scope of
5688 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5689 pushtag calling push_template_decl. We don't have to do
5690 this for enums because it will already have been done in
5693 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5694 pushtag (name, newtag, /*tag_scope=*/ts_current);
5697 else if (TREE_CODE (t) == FUNCTION_DECL
5698 || DECL_FUNCTION_TEMPLATE_P (t))
5700 /* Build new TYPE_METHODS. */
5703 if (TREE_CODE (t) == TEMPLATE_DECL)
5704 ++processing_template_decl;
5705 r = tsubst (t, args, tf_error, NULL_TREE);
5706 if (TREE_CODE (t) == TEMPLATE_DECL)
5707 --processing_template_decl;
5708 set_current_access_from_decl (r);
5709 grok_special_member_properties (r);
5710 finish_member_declaration (r);
5714 /* Build new TYPE_FIELDS. */
5716 if (TREE_CODE (t) != CONST_DECL)
5720 /* The the file and line for this declaration, to
5721 assist in error message reporting. Since we
5722 called push_tinst_level above, we don't need to
5724 input_location = DECL_SOURCE_LOCATION (t);
5726 if (TREE_CODE (t) == TEMPLATE_DECL)
5727 ++processing_template_decl;
5728 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5729 if (TREE_CODE (t) == TEMPLATE_DECL)
5730 --processing_template_decl;
5731 if (TREE_CODE (r) == VAR_DECL)
5735 [t]he initialization (and any associated
5736 side-effects) of a static data member does
5737 not occur unless the static data member is
5738 itself used in a way that requires the
5739 definition of the static data member to
5742 Therefore, we do not substitute into the
5743 initialized for the static data member here. */
5744 finish_static_data_member_decl
5747 /*asmspec_tree=*/NULL_TREE,
5749 if (DECL_INITIALIZED_IN_CLASS_P (r))
5750 check_static_variable_definition (r, TREE_TYPE (r));
5752 else if (TREE_CODE (r) == FIELD_DECL)
5754 /* Determine whether R has a valid type and can be
5755 completed later. If R is invalid, then it is
5756 replaced by error_mark_node so that it will not be
5757 added to TYPE_FIELDS. */
5758 tree rtype = TREE_TYPE (r);
5759 if (can_complete_type_without_circularity (rtype))
5760 complete_type (rtype);
5762 if (!COMPLETE_TYPE_P (rtype))
5764 cxx_incomplete_type_error (r, rtype);
5765 r = error_mark_node;
5769 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5770 such a thing will already have been added to the field
5771 list by tsubst_enum in finish_member_declaration in the
5772 CLASSTYPE_NESTED_UTDS case above. */
5773 if (!(TREE_CODE (r) == TYPE_DECL
5774 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5775 && DECL_ARTIFICIAL (r)))
5777 set_current_access_from_decl (r);
5778 finish_member_declaration (r);
5785 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5787 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5789 tree friend_type = t;
5790 bool adjust_processing_template_decl = false;
5792 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5794 /* template <class T> friend class C; */
5795 friend_type = tsubst_friend_class (friend_type, args);
5796 adjust_processing_template_decl = true;
5798 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5800 /* template <class T> friend class C::D; */
5801 friend_type = tsubst (friend_type, args,
5802 tf_error | tf_warning, NULL_TREE);
5803 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5804 friend_type = TREE_TYPE (friend_type);
5805 adjust_processing_template_decl = true;
5807 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5809 /* This could be either
5813 when dependent_type_p is false or
5815 template <class U> friend class T::C;
5818 friend_type = tsubst (friend_type, args,
5819 tf_error | tf_warning, NULL_TREE);
5820 /* Bump processing_template_decl for correct
5821 dependent_type_p calculation. */
5822 ++processing_template_decl;
5823 if (dependent_type_p (friend_type))
5824 adjust_processing_template_decl = true;
5825 --processing_template_decl;
5827 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
5828 && hidden_name_p (TYPE_NAME (friend_type)))
5832 where C hasn't been declared yet. Let's lookup name
5833 from namespace scope directly, bypassing any name that
5834 come from dependent base class. */
5835 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5837 /* The call to xref_tag_from_type does injection for friend
5839 push_nested_namespace (ns);
5841 xref_tag_from_type (friend_type, NULL_TREE,
5842 /*tag_scope=*/ts_current);
5843 pop_nested_namespace (ns);
5845 else if (uses_template_parms (friend_type))
5846 /* friend class C<T>; */
5847 friend_type = tsubst (friend_type, args,
5848 tf_error | tf_warning, NULL_TREE);
5853 where C is already declared or
5855 friend class C<int>;
5857 We don't have to do anything in these cases. */
5859 if (adjust_processing_template_decl)
5860 /* Trick make_friend_class into realizing that the friend
5861 we're adding is a template, not an ordinary class. It's
5862 important that we use make_friend_class since it will
5863 perform some error-checking and output cross-reference
5865 ++processing_template_decl;
5867 if (friend_type != error_mark_node)
5868 make_friend_class (type, friend_type, /*complain=*/false);
5870 if (adjust_processing_template_decl)
5871 --processing_template_decl;
5875 /* Build new DECL_FRIENDLIST. */
5878 /* The the file and line for this declaration, to
5879 assist in error message reporting. Since we
5880 called push_tinst_level above, we don't need to
5882 input_location = DECL_SOURCE_LOCATION (t);
5884 if (TREE_CODE (t) == TEMPLATE_DECL)
5886 ++processing_template_decl;
5887 push_deferring_access_checks (dk_no_check);
5890 r = tsubst_friend_function (t, args);
5891 add_friend (type, r, /*complain=*/false);
5892 if (TREE_CODE (t) == TEMPLATE_DECL)
5894 pop_deferring_access_checks ();
5895 --processing_template_decl;
5901 /* Set the file and line number information to whatever is given for
5902 the class itself. This puts error messages involving generated
5903 implicit functions at a predictable point, and the same point
5904 that would be used for non-template classes. */
5905 input_location = DECL_SOURCE_LOCATION (typedecl);
5907 unreverse_member_declarations (type);
5908 finish_struct_1 (type);
5909 TYPE_BEING_DEFINED (type) = 0;
5911 /* Now that the class is complete, instantiate default arguments for
5912 any member functions. We don't do this earlier because the
5913 default arguments may reference members of the class. */
5914 if (!PRIMARY_TEMPLATE_P (template))
5915 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5916 if (TREE_CODE (t) == FUNCTION_DECL
5917 /* Implicitly generated member functions will not have template
5918 information; they are not instantiations, but instead are
5919 created "fresh" for each instantiation. */
5920 && DECL_TEMPLATE_INFO (t))
5921 tsubst_default_arguments (t);
5924 pop_from_top_level ();
5925 pop_deferring_access_checks ();
5928 /* The vtable for a template class can be emitted in any translation
5929 unit in which the class is instantiated. When there is no key
5930 method, however, finish_struct_1 will already have added TYPE to
5931 the keyed_classes list. */
5932 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5933 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5939 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5945 else if (TYPE_P (t))
5946 r = tsubst (t, args, complain, in_decl);
5949 r = tsubst_expr (t, args, complain, in_decl);
5950 r = fold_non_dependent_expr (r);
5955 /* Substitute ARGS into the vector or list of template arguments T. */
5958 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5960 int len = TREE_VEC_LENGTH (t);
5961 int need_new = 0, i;
5962 tree *elts = alloca (len * sizeof (tree));
5964 for (i = 0; i < len; i++)
5966 tree orig_arg = TREE_VEC_ELT (t, i);
5969 if (TREE_CODE (orig_arg) == TREE_VEC)
5970 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5972 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5974 if (new_arg == error_mark_node)
5975 return error_mark_node;
5978 if (new_arg != orig_arg)
5985 t = make_tree_vec (len);
5986 for (i = 0; i < len; i++)
5987 TREE_VEC_ELT (t, i) = elts[i];
5992 /* Return the result of substituting ARGS into the template parameters
5993 given by PARMS. If there are m levels of ARGS and m + n levels of
5994 PARMS, then the result will contain n levels of PARMS. For
5995 example, if PARMS is `template <class T> template <class U>
5996 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
5997 result will be `template <int*, double, class V>'. */
6000 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
6005 for (new_parms = &r;
6006 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
6007 new_parms = &(TREE_CHAIN (*new_parms)),
6008 parms = TREE_CHAIN (parms))
6011 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
6014 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
6016 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
6017 tree default_value = TREE_PURPOSE (tuple);
6018 tree parm_decl = TREE_VALUE (tuple);
6020 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
6021 if (TREE_CODE (parm_decl) == PARM_DECL
6022 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
6023 parm_decl = error_mark_node;
6024 default_value = tsubst_template_arg (default_value, args,
6025 complain, NULL_TREE);
6027 tuple = build_tree_list (default_value, parm_decl);
6028 TREE_VEC_ELT (new_vec, i) = tuple;
6032 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6033 - TMPL_ARGS_DEPTH (args)),
6034 new_vec, NULL_TREE);
6040 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6041 type T. If T is not an aggregate or enumeration type, it is
6042 handled as if by tsubst. IN_DECL is as for tsubst. If
6043 ENTERING_SCOPE is nonzero, T is the context for a template which
6044 we are presently tsubst'ing. Return the substituted value. */
6047 tsubst_aggr_type (tree t,
6049 tsubst_flags_t complain,
6056 switch (TREE_CODE (t))
6059 if (TYPE_PTRMEMFUNC_P (t))
6060 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6062 /* Else fall through. */
6065 if (TYPE_TEMPLATE_INFO (t))
6070 bool saved_skip_evaluation;
6072 /* In "sizeof(X<I>)" we need to evaluate "I". */
6073 saved_skip_evaluation = skip_evaluation;
6074 skip_evaluation = false;
6076 /* First, determine the context for the type we are looking
6078 context = TYPE_CONTEXT (t);
6080 context = tsubst_aggr_type (context, args, complain,
6081 in_decl, /*entering_scope=*/1);
6083 /* Then, figure out what arguments are appropriate for the
6084 type we are trying to find. For example, given:
6086 template <class T> struct S;
6087 template <class T, class U> void f(T, U) { S<U> su; }
6089 and supposing that we are instantiating f<int, double>,
6090 then our ARGS will be {int, double}, but, when looking up
6091 S we only want {double}. */
6092 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6094 if (argvec == error_mark_node)
6095 r = error_mark_node;
6098 r = lookup_template_class (t, argvec, in_decl, context,
6099 entering_scope, complain);
6100 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6103 skip_evaluation = saved_skip_evaluation;
6108 /* This is not a template type, so there's nothing to do. */
6112 return tsubst (t, args, complain, in_decl);
6116 /* Substitute into the default argument ARG (a default argument for
6117 FN), which has the indicated TYPE. */
6120 tsubst_default_argument (tree fn, tree type, tree arg)
6122 tree saved_class_ptr = NULL_TREE;
6123 tree saved_class_ref = NULL_TREE;
6125 /* This default argument came from a template. Instantiate the
6126 default argument here, not in tsubst. In the case of
6135 we must be careful to do name lookup in the scope of S<T>,
6136 rather than in the current class. */
6137 push_access_scope (fn);
6138 /* The "this" pointer is not valid in a default argument. */
6141 saved_class_ptr = current_class_ptr;
6142 cp_function_chain->x_current_class_ptr = NULL_TREE;
6143 saved_class_ref = current_class_ref;
6144 cp_function_chain->x_current_class_ref = NULL_TREE;
6147 push_deferring_access_checks(dk_no_deferred);
6148 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6149 tf_error | tf_warning, NULL_TREE);
6150 pop_deferring_access_checks();
6152 /* Restore the "this" pointer. */
6155 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6156 cp_function_chain->x_current_class_ref = saved_class_ref;
6159 pop_access_scope (fn);
6161 /* Make sure the default argument is reasonable. */
6162 arg = check_default_argument (type, arg);
6167 /* Substitute into all the default arguments for FN. */
6170 tsubst_default_arguments (tree fn)
6175 tmpl_args = DECL_TI_ARGS (fn);
6177 /* If this function is not yet instantiated, we certainly don't need
6178 its default arguments. */
6179 if (uses_template_parms (tmpl_args))
6182 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6184 arg = TREE_CHAIN (arg))
6185 if (TREE_PURPOSE (arg))
6186 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6188 TREE_PURPOSE (arg));
6191 /* Substitute the ARGS into the T, which is a _DECL. Return the
6192 result of the substitution. Issue error and warning messages under
6193 control of COMPLAIN. */
6196 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6198 location_t saved_loc;
6202 /* Set the filename and linenumber to improve error-reporting. */
6203 saved_loc = input_location;
6204 input_location = DECL_SOURCE_LOCATION (t);
6206 switch (TREE_CODE (t))
6210 /* We can get here when processing a member function template,
6211 member class template, and template template parameter of
6212 a template class. */
6213 tree decl = DECL_TEMPLATE_RESULT (t);
6218 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6220 /* Template template parameter is treated here. */
6221 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6222 if (new_type == error_mark_node)
6223 return error_mark_node;
6226 TREE_CHAIN (r) = NULL_TREE;
6227 TREE_TYPE (r) = new_type;
6228 DECL_TEMPLATE_RESULT (r)
6229 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6230 DECL_TEMPLATE_PARMS (r)
6231 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6233 TYPE_NAME (new_type) = r;
6237 /* We might already have an instance of this template.
6238 The ARGS are for the surrounding class type, so the
6239 full args contain the tsubst'd args for the context,
6240 plus the innermost args from the template decl. */
6241 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6242 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6243 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6244 full_args = tsubst_template_args (tmpl_args, args,
6246 if (full_args == error_mark_node)
6247 return error_mark_node;
6249 /* tsubst_template_args doesn't copy the vector if
6250 nothing changed. But, *something* should have
6252 gcc_assert (full_args != tmpl_args);
6254 spec = retrieve_specialization (t, full_args,
6255 /*class_specializations_p=*/true);
6256 if (spec != NULL_TREE)
6262 /* Make a new template decl. It will be similar to the
6263 original, but will record the current template arguments.
6264 We also create a new function declaration, which is just
6265 like the old one, but points to this new template, rather
6266 than the old one. */
6268 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6269 TREE_CHAIN (r) = NULL_TREE;
6272 = tsubst_aggr_type (DECL_CONTEXT (t), args,
6274 /*entering_scope=*/1);
6275 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6277 if (TREE_CODE (decl) == TYPE_DECL)
6279 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6280 if (new_type == error_mark_node)
6281 return error_mark_node;
6283 TREE_TYPE (r) = new_type;
6284 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6285 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6286 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6290 tree new_decl = tsubst (decl, args, complain, in_decl);
6291 if (new_decl == error_mark_node)
6292 return error_mark_node;
6294 DECL_TEMPLATE_RESULT (r) = new_decl;
6295 DECL_TI_TEMPLATE (new_decl) = r;
6296 TREE_TYPE (r) = TREE_TYPE (new_decl);
6297 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6300 SET_DECL_IMPLICIT_INSTANTIATION (r);
6301 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6302 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6304 /* The template parameters for this new template are all the
6305 template parameters for the old template, except the
6306 outermost level of parameters. */
6307 DECL_TEMPLATE_PARMS (r)
6308 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6311 if (PRIMARY_TEMPLATE_P (t))
6312 DECL_PRIMARY_TEMPLATE (r) = r;
6314 if (TREE_CODE (decl) != TYPE_DECL)
6315 /* Record this non-type partial instantiation. */
6316 register_specialization (r, t,
6317 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
6325 tree argvec = NULL_TREE;
6333 /* Nobody should be tsubst'ing into non-template functions. */
6334 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6336 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6341 /* If T is not dependent, just return it. We have to
6342 increment PROCESSING_TEMPLATE_DECL because
6343 value_dependent_expression_p assumes that nothing is
6344 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6345 ++processing_template_decl;
6346 dependent_p = value_dependent_expression_p (t);
6347 --processing_template_decl;
6351 /* Calculate the most general template of which R is a
6352 specialization, and the complete set of arguments used to
6354 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6355 argvec = tsubst_template_args (DECL_TI_ARGS
6356 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6357 args, complain, in_decl);
6359 /* Check to see if we already have this specialization. */
6360 spec = retrieve_specialization (gen_tmpl, argvec,
6361 /*class_specializations_p=*/false);
6369 /* We can see more levels of arguments than parameters if
6370 there was a specialization of a member template, like
6373 template <class T> struct S { template <class U> void f(); }
6374 template <> template <class U> void S<int>::f(U);
6376 Here, we'll be substituting into the specialization,
6377 because that's where we can find the code we actually
6378 want to generate, but we'll have enough arguments for
6379 the most general template.
6381 We also deal with the peculiar case:
6383 template <class T> struct S {
6384 template <class U> friend void f();
6386 template <class U> void f() {}
6388 template void f<double>();
6390 Here, the ARGS for the instantiation of will be {int,
6391 double}. But, we only need as many ARGS as there are
6392 levels of template parameters in CODE_PATTERN. We are
6393 careful not to get fooled into reducing the ARGS in
6396 template <class T> struct S { template <class U> void f(U); }
6397 template <class T> template <> void S<T>::f(int) {}
6399 which we can spot because the pattern will be a
6400 specialization in this case. */
6401 args_depth = TMPL_ARGS_DEPTH (args);
6403 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6404 if (args_depth > parms_depth
6405 && !DECL_TEMPLATE_SPECIALIZATION (t))
6406 args = get_innermost_template_args (args, parms_depth);
6410 /* This special case arises when we have something like this:
6412 template <class T> struct S {
6413 friend void f<int>(int, double);
6416 Here, the DECL_TI_TEMPLATE for the friend declaration
6417 will be an IDENTIFIER_NODE. We are being called from
6418 tsubst_friend_function, and we want only to create a
6419 new decl (R) with appropriate types so that we can call
6420 determine_specialization. */
6421 gen_tmpl = NULL_TREE;
6424 if (DECL_CLASS_SCOPE_P (t))
6426 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6430 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6431 complain, t, /*entering_scope=*/1);
6436 ctx = DECL_CONTEXT (t);
6438 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6439 if (type == error_mark_node)
6440 return error_mark_node;
6442 /* We do NOT check for matching decls pushed separately at this
6443 point, as they may not represent instantiations of this
6444 template, and in any case are considered separate under the
6447 DECL_USE_TEMPLATE (r) = 0;
6448 TREE_TYPE (r) = type;
6449 /* Clear out the mangled name and RTL for the instantiation. */
6450 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6451 SET_DECL_RTL (r, NULL_RTX);
6452 DECL_INITIAL (r) = NULL_TREE;
6453 DECL_CONTEXT (r) = ctx;
6455 if (member && DECL_CONV_FN_P (r))
6456 /* Type-conversion operator. Reconstruct the name, in
6457 case it's the name of one of the template's parameters. */
6458 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6460 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6462 DECL_RESULT (r) = NULL_TREE;
6464 TREE_STATIC (r) = 0;
6465 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6466 DECL_EXTERNAL (r) = 1;
6467 /* If this is an instantiation of a function with internal
6468 linkage, we already know what object file linkage will be
6469 assigned to the instantiation. */
6470 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6471 DECL_DEFER_OUTPUT (r) = 0;
6472 TREE_CHAIN (r) = NULL_TREE;
6473 DECL_PENDING_INLINE_INFO (r) = 0;
6474 DECL_PENDING_INLINE_P (r) = 0;
6475 DECL_SAVED_TREE (r) = NULL_TREE;
6477 if (DECL_CLONED_FUNCTION (r))
6479 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6481 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6482 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6485 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6486 this in the special friend case mentioned above where
6487 GEN_TMPL is NULL. */
6490 DECL_TEMPLATE_INFO (r)
6491 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6492 SET_DECL_IMPLICIT_INSTANTIATION (r);
6493 register_specialization (r, gen_tmpl, argvec, false);
6495 /* We're not supposed to instantiate default arguments
6496 until they are called, for a template. But, for a
6499 template <class T> void f ()
6500 { extern void g(int i = T()); }
6502 we should do the substitution when the template is
6503 instantiated. We handle the member function case in
6504 instantiate_class_template since the default arguments
6505 might refer to other members of the class. */
6507 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6508 && !uses_template_parms (argvec))
6509 tsubst_default_arguments (r);
6512 DECL_TEMPLATE_INFO (r) = NULL_TREE;
6514 /* Copy the list of befriending classes. */
6515 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6517 friends = &TREE_CHAIN (*friends))
6519 *friends = copy_node (*friends);
6520 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6525 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6527 maybe_retrofit_in_chrg (r);
6528 if (DECL_CONSTRUCTOR_P (r))
6529 grok_ctor_properties (ctx, r);
6530 /* If this is an instantiation of a member template, clone it.
6531 If it isn't, that'll be handled by
6532 clone_constructors_and_destructors. */
6533 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6534 clone_function_decl (r, /*update_method_vec_p=*/0);
6536 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6537 grok_op_properties (r, (complain & tf_error) != 0);
6539 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6540 SET_DECL_FRIEND_CONTEXT (r,
6541 tsubst (DECL_FRIEND_CONTEXT (t),
6542 args, complain, in_decl));
6551 if (DECL_TEMPLATE_PARM_P (t))
6552 SET_DECL_TEMPLATE_PARM_P (r);
6554 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6555 type = type_decays_to (type);
6556 TREE_TYPE (r) = type;
6557 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6559 if (DECL_INITIAL (r))
6561 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6562 DECL_INITIAL (r) = TREE_TYPE (r);
6564 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6568 DECL_CONTEXT (r) = NULL_TREE;
6570 if (!DECL_TEMPLATE_PARM_P (r))
6571 DECL_ARG_TYPE (r) = type_passed_as (type);
6573 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6574 complain, TREE_CHAIN (t));
6583 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6584 if (type == error_mark_node)
6585 return error_mark_node;
6586 TREE_TYPE (r) = type;
6587 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6589 /* We don't have to set DECL_CONTEXT here; it is set by
6590 finish_member_declaration. */
6591 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6593 TREE_CHAIN (r) = NULL_TREE;
6594 if (VOID_TYPE_P (type))
6595 error ("instantiation of %q+D as type %qT", r, type);
6600 /* We reach here only for member using decls. */
6601 if (DECL_DEPENDENT_P (t))
6603 r = do_class_using_decl
6604 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
6605 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
6607 r = error_mark_node;
6612 TREE_CHAIN (r) = NULL_TREE;
6619 tree argvec = NULL_TREE;
6620 tree gen_tmpl = NULL_TREE;
6622 tree tmpl = NULL_TREE;
6624 tree type = NULL_TREE;
6627 if (TREE_CODE (t) == TYPE_DECL)
6629 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6630 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6631 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6633 /* If this is the canonical decl, we don't have to
6634 mess with instantiations, and often we can't (for
6635 typename, template type parms and such). Note that
6636 TYPE_NAME is not correct for the above test if
6637 we've copied the type for a typedef. */
6638 r = TYPE_NAME (type);
6643 /* Assume this is a non-local variable. */
6646 if (TYPE_P (CP_DECL_CONTEXT (t)))
6647 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6649 in_decl, /*entering_scope=*/1);
6650 else if (DECL_NAMESPACE_SCOPE_P (t))
6651 ctx = DECL_CONTEXT (t);
6654 /* Subsequent calls to pushdecl will fill this in. */
6659 /* Check to see if we already have this specialization. */
6662 tmpl = DECL_TI_TEMPLATE (t);
6663 gen_tmpl = most_general_template (tmpl);
6664 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6665 spec = retrieve_specialization (gen_tmpl, argvec,
6666 /*class_specializations_p=*/false);
6669 spec = retrieve_local_specialization (t);
6678 if (TREE_CODE (r) == VAR_DECL)
6680 /* Even if the original location is out of scope, the
6681 newly substituted one is not. */
6682 DECL_DEAD_FOR_LOCAL (r) = 0;
6683 DECL_INITIALIZED_P (r) = 0;
6684 DECL_TEMPLATE_INSTANTIATED (r) = 0;
6685 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6686 if (type == error_mark_node)
6687 return error_mark_node;
6688 type = complete_type (type);
6689 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6690 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6691 type = check_var_type (DECL_NAME (r), type);
6693 if (DECL_HAS_VALUE_EXPR_P (t))
6695 tree ve = DECL_VALUE_EXPR (t);
6696 ve = tsubst_expr (ve, args, complain, in_decl);
6697 SET_DECL_VALUE_EXPR (r, ve);
6700 else if (DECL_SELF_REFERENCE_P (t))
6701 SET_DECL_SELF_REFERENCE_P (r);
6702 TREE_TYPE (r) = type;
6703 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6704 DECL_CONTEXT (r) = ctx;
6705 /* Clear out the mangled name and RTL for the instantiation. */
6706 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6707 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6708 SET_DECL_RTL (r, NULL_RTX);
6709 /* The initializer must not be expanded until it is required;
6711 DECL_INITIAL (r) = NULL_TREE;
6712 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6713 SET_DECL_RTL (r, NULL_RTX);
6714 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6718 /* A static data member declaration is always marked
6719 external when it is declared in-class, even if an
6720 initializer is present. We mimic the non-template
6722 DECL_EXTERNAL (r) = 1;
6724 register_specialization (r, gen_tmpl, argvec, false);
6725 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6726 SET_DECL_IMPLICIT_INSTANTIATION (r);
6729 register_local_specialization (r, t);
6731 TREE_CHAIN (r) = NULL_TREE;
6740 /* Restore the file and line information. */
6741 input_location = saved_loc;
6746 /* Substitute into the ARG_TYPES of a function type. */
6749 tsubst_arg_types (tree arg_types,
6751 tsubst_flags_t complain,
6754 tree remaining_arg_types;
6757 tree result = NULL_TREE;
6759 if (!arg_types || arg_types == void_list_node)
6762 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6763 args, complain, in_decl);
6764 if (remaining_arg_types == error_mark_node)
6765 return error_mark_node;
6767 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6768 if (type == error_mark_node)
6769 return error_mark_node;
6770 if (VOID_TYPE_P (type))
6772 if (complain & tf_error)
6774 error ("invalid parameter type %qT", type);
6776 error ("in declaration %q+D", in_decl);
6778 return error_mark_node;
6781 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6782 top-level qualifiers as required. */
6783 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6785 /* We do not substitute into default arguments here. The standard
6786 mandates that they be instantiated only when needed, which is
6787 done in build_over_call. */
6788 default_arg = TREE_PURPOSE (arg_types);
6790 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
6792 /* We've instantiated a template before its default arguments
6793 have been parsed. This can happen for a nested template
6794 class, and is not an error unless we require the default
6795 argument in a call of this function. */
6796 result = tree_cons (default_arg, type, remaining_arg_types);
6797 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), result);
6800 result = hash_tree_cons (default_arg, type, remaining_arg_types);
6805 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6806 *not* handle the exception-specification for FNTYPE, because the
6807 initial substitution of explicitly provided template parameters
6808 during argument deduction forbids substitution into the
6809 exception-specification:
6813 All references in the function type of the function template to the
6814 corresponding template parameters are replaced by the specified tem-
6815 plate argument values. If a substitution in a template parameter or
6816 in the function type of the function template results in an invalid
6817 type, type deduction fails. [Note: The equivalent substitution in
6818 exception specifications is done only when the function is instanti-
6819 ated, at which point a program is ill-formed if the substitution
6820 results in an invalid type.] */
6823 tsubst_function_type (tree t,
6825 tsubst_flags_t complain,
6832 /* The TYPE_CONTEXT is not used for function/method types. */
6833 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6835 /* Substitute the return type. */
6836 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6837 if (return_type == error_mark_node)
6838 return error_mark_node;
6839 /* The standard does not presently indicate that creation of a
6840 function type with an invalid return type is a deduction failure.
6841 However, that is clearly analogous to creating an array of "void"
6842 or a reference to a reference. This is core issue #486. */
6843 if (TREE_CODE (return_type) == ARRAY_TYPE
6844 || TREE_CODE (return_type) == FUNCTION_TYPE)
6846 if (complain & tf_error)
6848 if (TREE_CODE (return_type) == ARRAY_TYPE)
6849 error ("function returning an array");
6851 error ("function returning a function");
6853 return error_mark_node;
6856 /* Substitute the argument types. */
6857 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6859 if (arg_types == error_mark_node)
6860 return error_mark_node;
6862 /* Construct a new type node and return it. */
6863 if (TREE_CODE (t) == FUNCTION_TYPE)
6864 fntype = build_function_type (return_type, arg_types);
6867 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6868 if (! IS_AGGR_TYPE (r))
6872 Type deduction may fail for any of the following
6875 -- Attempting to create "pointer to member of T" when T
6876 is not a class type. */
6877 if (complain & tf_error)
6878 error ("creating pointer to member function of non-class type %qT",
6880 return error_mark_node;
6883 fntype = build_method_type_directly (r, return_type,
6884 TREE_CHAIN (arg_types));
6886 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6887 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6892 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6893 ARGS into that specification, and return the substituted
6894 specification. If there is no specification, return NULL_TREE. */
6897 tsubst_exception_specification (tree fntype,
6899 tsubst_flags_t complain,
6905 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6906 new_specs = NULL_TREE;
6909 if (! TREE_VALUE (specs))
6915 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6916 if (spec == error_mark_node)
6918 new_specs = add_exception_specifier (new_specs, spec, complain);
6919 specs = TREE_CHAIN (specs);
6925 /* Substitute into the PARMS of a call-declarator. */
6928 tsubst_call_declarator_parms (tree parms,
6930 tsubst_flags_t complain,
6937 if (!parms || parms == void_list_node)
6940 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6941 args, complain, in_decl);
6943 /* Figure out the type of this parameter. */
6944 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6946 /* Figure out the default argument as well. Note that we use
6947 tsubst_expr since the default argument is really an expression. */
6948 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6950 /* Chain this parameter on to the front of those we have already
6951 processed. We don't use hash_tree_cons because that function
6952 doesn't check TREE_PARMLIST. */
6953 new_parms = tree_cons (defarg, type, new_parms);
6958 /* Take the tree structure T and replace template parameters used
6959 therein with the argument vector ARGS. IN_DECL is an associated
6960 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6961 Issue error and warning messages under control of COMPLAIN. Note
6962 that we must be relatively non-tolerant of extensions here, in
6963 order to preserve conformance; if we allow substitutions that
6964 should not be allowed, we may allow argument deductions that should
6965 not succeed, and therefore report ambiguous overload situations
6966 where there are none. In theory, we could allow the substitution,
6967 but indicate that it should have failed, and allow our caller to
6968 make sure that the right thing happens, but we don't try to do this
6971 This function is used for dealing with types, decls and the like;
6972 for expressions, use tsubst_expr or tsubst_copy. */
6975 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
6979 if (t == NULL_TREE || t == error_mark_node
6980 || t == integer_type_node
6981 || t == void_type_node
6982 || t == char_type_node
6983 || t == unknown_type_node
6984 || TREE_CODE (t) == NAMESPACE_DECL)
6988 return tsubst_decl (t, args, complain);
6990 if (TREE_CODE (t) == IDENTIFIER_NODE)
6991 type = IDENTIFIER_TYPE_VALUE (t);
6993 type = TREE_TYPE (t);
6995 gcc_assert (type != unknown_type_node);
6998 && TREE_CODE (t) != TYPENAME_TYPE
6999 && TREE_CODE (t) != IDENTIFIER_NODE
7000 && TREE_CODE (t) != FUNCTION_TYPE
7001 && TREE_CODE (t) != METHOD_TYPE)
7002 type = tsubst (type, args, complain, in_decl);
7003 if (type == error_mark_node)
7004 return error_mark_node;
7006 switch (TREE_CODE (t))
7011 return tsubst_aggr_type (t, args, complain, in_decl,
7012 /*entering_scope=*/0);
7015 case IDENTIFIER_NODE:
7027 if (t == integer_type_node)
7030 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
7031 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
7035 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
7037 /* The array dimension behaves like a non-type template arg,
7038 in that we want to fold it as much as possible. */
7039 max = tsubst_template_arg (omax, args, complain, in_decl);
7040 max = fold_decl_constant_value (max);
7042 if (integer_zerop (omax))
7044 /* Still allow an explicit array of size zero. */
7046 pedwarn ("creating array with size zero");
7048 else if (integer_zerop (max)
7049 || (TREE_CODE (max) == INTEGER_CST
7050 && INT_CST_LT (max, integer_zero_node)))
7054 Type deduction may fail for any of the following
7057 Attempting to create an array with a size that is
7058 zero or negative. */
7059 if (complain & tf_error)
7060 error ("creating array with size zero (%qE)", max);
7062 return error_mark_node;
7065 return compute_array_index_type (NULL_TREE, max);
7068 case TEMPLATE_TYPE_PARM:
7069 case TEMPLATE_TEMPLATE_PARM:
7070 case BOUND_TEMPLATE_TEMPLATE_PARM:
7071 case TEMPLATE_PARM_INDEX:
7076 tree arg = NULL_TREE;
7080 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7081 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7082 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7083 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7085 idx = TEMPLATE_TYPE_IDX (t);
7086 level = TEMPLATE_TYPE_LEVEL (t);
7090 idx = TEMPLATE_PARM_IDX (t);
7091 level = TEMPLATE_PARM_LEVEL (t);
7094 levels = TMPL_ARGS_DEPTH (args);
7095 if (level <= levels)
7096 arg = TMPL_ARG (args, level, idx);
7098 if (arg == error_mark_node)
7099 return error_mark_node;
7100 else if (arg != NULL_TREE)
7102 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7104 gcc_assert (TYPE_P (arg));
7105 return cp_build_qualified_type_real
7106 (arg, cp_type_quals (arg) | cp_type_quals (t),
7107 complain | tf_ignore_bad_quals);
7109 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7111 /* We are processing a type constructed from a
7112 template template parameter. */
7113 tree argvec = tsubst (TYPE_TI_ARGS (t),
7114 args, complain, in_decl);
7115 if (argvec == error_mark_node)
7116 return error_mark_node;
7118 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7119 are resolving nested-types in the signature of a
7120 member function templates. Otherwise ARG is a
7121 TEMPLATE_DECL and is the real template to be
7123 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7124 arg = TYPE_NAME (arg);
7126 r = lookup_template_class (arg,
7129 /*entering_scope=*/0,
7131 return cp_build_qualified_type_real
7132 (r, TYPE_QUALS (t), complain);
7135 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7140 /* This can happen during the attempted tsubst'ing in
7141 unify. This means that we don't yet have any information
7142 about the template parameter in question. */
7145 /* If we get here, we must have been looking at a parm for a
7146 more deeply nested template. Make a new version of this
7147 template parameter, but with a lower level. */
7148 switch (TREE_CODE (t))
7150 case TEMPLATE_TYPE_PARM:
7151 case TEMPLATE_TEMPLATE_PARM:
7152 case BOUND_TEMPLATE_TEMPLATE_PARM:
7153 if (cp_type_quals (t))
7155 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7156 r = cp_build_qualified_type_real
7157 (r, cp_type_quals (t),
7158 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7159 ? tf_ignore_bad_quals : 0));
7164 TEMPLATE_TYPE_PARM_INDEX (r)
7165 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7167 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7168 TYPE_MAIN_VARIANT (r) = r;
7169 TYPE_POINTER_TO (r) = NULL_TREE;
7170 TYPE_REFERENCE_TO (r) = NULL_TREE;
7172 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7174 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7176 if (argvec == error_mark_node)
7177 return error_mark_node;
7179 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7180 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7185 case TEMPLATE_PARM_INDEX:
7186 r = reduce_template_parm_level (t, type, levels);
7198 tree purpose, value, chain;
7200 if (t == void_list_node)
7203 purpose = TREE_PURPOSE (t);
7206 purpose = tsubst (purpose, args, complain, in_decl);
7207 if (purpose == error_mark_node)
7208 return error_mark_node;
7210 value = TREE_VALUE (t);
7213 value = tsubst (value, args, complain, in_decl);
7214 if (value == error_mark_node)
7215 return error_mark_node;
7217 chain = TREE_CHAIN (t);
7218 if (chain && chain != void_type_node)
7220 chain = tsubst (chain, args, complain, in_decl);
7221 if (chain == error_mark_node)
7222 return error_mark_node;
7224 if (purpose == TREE_PURPOSE (t)
7225 && value == TREE_VALUE (t)
7226 && chain == TREE_CHAIN (t))
7228 return hash_tree_cons (purpose, value, chain);
7232 /* We should never be tsubsting a binfo. */
7236 /* A vector of template arguments. */
7238 return tsubst_template_args (t, args, complain, in_decl);
7241 case REFERENCE_TYPE:
7243 enum tree_code code;
7245 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7248 code = TREE_CODE (t);
7253 Type deduction may fail for any of the following
7256 -- Attempting to create a pointer to reference type.
7257 -- Attempting to create a reference to a reference type or
7258 a reference to void. */
7259 if (TREE_CODE (type) == REFERENCE_TYPE
7260 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7262 static location_t last_loc;
7264 /* We keep track of the last time we issued this error
7265 message to avoid spewing a ton of messages during a
7266 single bad template instantiation. */
7267 if (complain & tf_error
7268 #ifdef USE_MAPPED_LOCATION
7269 && last_loc != input_location
7271 && (last_loc.line != input_line
7272 || last_loc.file != input_filename)
7276 if (TREE_CODE (type) == VOID_TYPE)
7277 error ("forming reference to void");
7279 error ("forming %s to reference type %qT",
7280 (code == POINTER_TYPE) ? "pointer" : "reference",
7282 last_loc = input_location;
7285 return error_mark_node;
7287 else if (code == POINTER_TYPE)
7289 r = build_pointer_type (type);
7290 if (TREE_CODE (type) == METHOD_TYPE)
7291 r = build_ptrmemfunc_type (r);
7294 r = build_reference_type (type);
7295 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7297 if (r != error_mark_node)
7298 /* Will this ever be needed for TYPE_..._TO values? */
7305 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7306 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7310 Type deduction may fail for any of the following
7313 -- Attempting to create "pointer to member of T" when T
7314 is not a class type. */
7315 if (complain & tf_error)
7316 error ("creating pointer to member of non-class type %qT", r);
7317 return error_mark_node;
7319 if (TREE_CODE (type) == REFERENCE_TYPE)
7321 if (complain & tf_error)
7322 error ("creating pointer to member reference type %qT", type);
7323 return error_mark_node;
7325 if (TREE_CODE (type) == VOID_TYPE)
7327 if (complain & tf_error)
7328 error ("creating pointer to member of type void");
7329 return error_mark_node;
7331 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7332 if (TREE_CODE (type) == FUNCTION_TYPE)
7334 /* The type of the implicit object parameter gets its
7335 cv-qualifiers from the FUNCTION_TYPE. */
7337 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
7338 cp_type_quals (type));
7340 method_type = build_method_type_directly (this_type,
7342 TYPE_ARG_TYPES (type));
7343 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
7344 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
7348 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7357 fntype = tsubst_function_type (t, args, complain, in_decl);
7358 if (fntype == error_mark_node)
7359 return error_mark_node;
7361 /* Substitute the exception specification. */
7362 specs = tsubst_exception_specification (t, args, complain,
7364 if (specs == error_mark_node)
7365 return error_mark_node;
7367 fntype = build_exception_variant (fntype, specs);
7372 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7373 if (domain == error_mark_node)
7374 return error_mark_node;
7376 /* As an optimization, we avoid regenerating the array type if
7377 it will obviously be the same as T. */
7378 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7381 /* These checks should match the ones in grokdeclarator.
7385 The deduction may fail for any of the following reasons:
7387 -- Attempting to create an array with an element type that
7388 is void, a function type, or a reference type, or [DR337]
7389 an abstract class type. */
7390 if (TREE_CODE (type) == VOID_TYPE
7391 || TREE_CODE (type) == FUNCTION_TYPE
7392 || TREE_CODE (type) == REFERENCE_TYPE)
7394 if (complain & tf_error)
7395 error ("creating array of %qT", type);
7396 return error_mark_node;
7398 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7400 if (complain & tf_error)
7401 error ("creating array of %qT, which is an abstract class type",
7403 return error_mark_node;
7406 r = build_cplus_array_type (type, domain);
7413 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7414 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7416 if (e1 == error_mark_node || e2 == error_mark_node)
7417 return error_mark_node;
7419 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
7425 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7426 if (e == error_mark_node)
7427 return error_mark_node;
7429 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
7434 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7435 in_decl, /*entering_scope=*/1);
7436 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7439 if (ctx == error_mark_node || f == error_mark_node)
7440 return error_mark_node;
7442 if (!IS_AGGR_TYPE (ctx))
7444 if (complain & tf_error)
7445 error ("%qT is not a class, struct, or union type", ctx);
7446 return error_mark_node;
7448 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7450 /* Normally, make_typename_type does not require that the CTX
7451 have complete type in order to allow things like:
7453 template <class T> struct S { typename S<T>::X Y; };
7455 But, such constructs have already been resolved by this
7456 point, so here CTX really should have complete type, unless
7457 it's a partial instantiation. */
7458 ctx = complete_type (ctx);
7459 if (!COMPLETE_TYPE_P (ctx))
7461 if (complain & tf_error)
7462 cxx_incomplete_type_error (NULL_TREE, ctx);
7463 return error_mark_node;
7467 f = make_typename_type (ctx, f, typename_type,
7468 (complain & tf_error) | tf_keep_type_decl);
7469 if (f == error_mark_node)
7471 if (TREE_CODE (f) == TYPE_DECL)
7473 complain |= tf_ignore_bad_quals;
7477 if (TREE_CODE (f) != TYPENAME_TYPE)
7479 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7480 error ("%qT resolves to %qT, which is not an enumeration type",
7482 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7483 error ("%qT resolves to %qT, which is is not a class type",
7487 return cp_build_qualified_type_real
7488 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7491 case UNBOUND_CLASS_TEMPLATE:
7493 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7494 in_decl, /*entering_scope=*/1);
7495 tree name = TYPE_IDENTIFIER (t);
7496 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7498 if (ctx == error_mark_node || name == error_mark_node)
7499 return error_mark_node;
7502 parm_list = tsubst_template_parms (parm_list, args, complain);
7503 return make_unbound_class_template (ctx, name, parm_list, complain);
7513 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7514 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7515 if (e1 == error_mark_node || e2 == error_mark_node)
7516 return error_mark_node;
7518 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7523 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7524 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7525 if (e1 == error_mark_node || e2 == error_mark_node)
7526 return error_mark_node;
7528 return build_nt (TREE_CODE (t), e1, e2);
7535 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7536 complain, in_decl));
7537 return cp_build_qualified_type_real (type,
7539 | cp_type_quals (type),
7544 sorry ("use of %qs in template",
7545 tree_code_name [(int) TREE_CODE (t)]);
7546 return error_mark_node;
7550 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7551 type of the expression on the left-hand side of the "." or "->"
7555 tsubst_baselink (tree baselink, tree object_type,
7556 tree args, tsubst_flags_t complain, tree in_decl)
7559 tree qualifying_scope;
7561 tree template_args = 0;
7562 bool template_id_p = false;
7564 /* A baselink indicates a function from a base class. The
7565 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7566 non-dependent types; otherwise, the lookup could not have
7567 succeeded. However, they may indicate bases of the template
7568 class, rather than the instantiated class.
7570 In addition, lookups that were not ambiguous before may be
7571 ambiguous now. Therefore, we perform the lookup again. */
7572 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7573 fns = BASELINK_FUNCTIONS (baselink);
7574 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7576 template_id_p = true;
7577 template_args = TREE_OPERAND (fns, 1);
7578 fns = TREE_OPERAND (fns, 0);
7580 template_args = tsubst_template_args (template_args, args,
7583 name = DECL_NAME (get_first_fn (fns));
7584 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7586 /* If lookup found a single function, mark it as used at this
7587 point. (If it lookup found multiple functions the one selected
7588 later by overload resolution will be marked as used at that
7590 if (BASELINK_P (baselink))
7591 fns = BASELINK_FUNCTIONS (baselink);
7592 if (!template_id_p && !really_overloaded_fn (fns))
7593 mark_used (OVL_CURRENT (fns));
7595 /* Add back the template arguments, if present. */
7596 if (BASELINK_P (baselink) && template_id_p)
7597 BASELINK_FUNCTIONS (baselink)
7598 = build_nt (TEMPLATE_ID_EXPR,
7599 BASELINK_FUNCTIONS (baselink),
7603 object_type = current_class_type;
7604 return adjust_result_of_qualified_name_lookup (baselink,
7609 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7610 true if the qualified-id will be a postfix-expression in-and-of
7611 itself; false if more of the postfix-expression follows the
7612 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7616 tsubst_qualified_id (tree qualified_id, tree args,
7617 tsubst_flags_t complain, tree in_decl,
7618 bool done, bool address_p)
7626 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7628 /* Figure out what name to look up. */
7629 name = TREE_OPERAND (qualified_id, 1);
7630 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7633 template_args = TREE_OPERAND (name, 1);
7635 template_args = tsubst_template_args (template_args, args,
7637 name = TREE_OPERAND (name, 0);
7641 is_template = false;
7642 template_args = NULL_TREE;
7645 /* Substitute into the qualifying scope. When there are no ARGS, we
7646 are just trying to simplify a non-dependent expression. In that
7647 case the qualifying scope may be dependent, and, in any case,
7648 substituting will not help. */
7649 scope = TREE_OPERAND (qualified_id, 0);
7652 scope = tsubst (scope, args, complain, in_decl);
7653 expr = tsubst_copy (name, args, complain, in_decl);
7658 if (dependent_type_p (scope))
7659 return build_nt (SCOPE_REF, scope, expr);
7661 if (!BASELINK_P (name) && !DECL_P (expr))
7663 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7664 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7665 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7667 if (complain & tf_error)
7669 error ("dependent-name %qE is parsed as a non-type, but "
7670 "instantiation yields a type", qualified_id);
7671 inform ("say %<typename %E%> if a type is meant", qualified_id);
7673 return error_mark_node;
7679 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7681 /* Remember that there was a reference to this entity. */
7685 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7687 if (complain & tf_error)
7688 qualified_name_lookup_error (scope,
7689 TREE_OPERAND (qualified_id, 1),
7691 return error_mark_node;
7695 expr = lookup_template_function (expr, template_args);
7697 if (expr == error_mark_node && complain & tf_error)
7698 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7700 else if (TYPE_P (scope))
7702 expr = (adjust_result_of_qualified_name_lookup
7703 (expr, scope, current_class_type));
7704 expr = finish_qualified_id_expr (scope, expr, done, address_p);
7707 if (TREE_CODE (expr) != SCOPE_REF)
7708 expr = convert_from_reference (expr);
7713 /* Like tsubst, but deals with expressions. This function just replaces
7714 template parms; to finish processing the resultant expression, use
7718 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7720 enum tree_code code;
7723 if (t == NULL_TREE || t == error_mark_node)
7726 code = TREE_CODE (t);
7731 r = retrieve_local_specialization (t);
7732 gcc_assert (r != NULL);
7741 if (DECL_TEMPLATE_PARM_P (t))
7742 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7743 /* There is no need to substitute into namespace-scope
7745 if (DECL_NAMESPACE_SCOPE_P (t))
7747 /* If ARGS is NULL, then T is known to be non-dependent. */
7748 if (args == NULL_TREE)
7749 return integral_constant_value (t);
7751 /* Unfortunately, we cannot just call lookup_name here.
7754 template <int I> int f() {
7756 struct S { void g() { E e = a; } };
7759 When we instantiate f<7>::S::g(), say, lookup_name is not
7760 clever enough to find f<7>::a. */
7762 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7763 /*entering_scope=*/0);
7765 for (v = TYPE_VALUES (enum_type);
7768 if (TREE_PURPOSE (v) == DECL_NAME (t))
7769 return TREE_VALUE (v);
7771 /* We didn't find the name. That should never happen; if
7772 name-lookup found it during preliminary parsing, we
7773 should find it again here during instantiation. */
7779 if (DECL_CONTEXT (t))
7783 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7784 /*entering_scope=*/1);
7785 if (ctx != DECL_CONTEXT (t))
7787 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7790 if (complain & tf_error)
7791 error ("using invalid field %qD", t);
7792 return error_mark_node;
7802 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7803 || local_variable_p (t))
7804 t = tsubst (t, args, complain, in_decl);
7809 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7812 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7813 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7814 args, complain, in_decl);
7815 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7816 return tsubst (t, args, complain, in_decl);
7817 else if (DECL_CLASS_SCOPE_P (t)
7818 && uses_template_parms (DECL_CONTEXT (t)))
7820 /* Template template argument like the following example need
7823 template <template <class> class TT> struct C {};
7824 template <class T> struct D {
7825 template <class U> struct E {};
7830 We are processing the template argument `E' in #1 for
7831 the template instantiation #2. Originally, `E' is a
7832 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7833 have to substitute this with one having context `D<int>'. */
7835 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7836 return lookup_field (context, DECL_NAME(t), 0, false);
7839 /* Ordinary template template argument. */
7843 case REINTERPRET_CAST_EXPR:
7844 case CONST_CAST_EXPR:
7845 case STATIC_CAST_EXPR:
7846 case DYNAMIC_CAST_EXPR:
7849 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7850 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7854 case TRUTH_NOT_EXPR:
7857 case UNARY_PLUS_EXPR: /* Unary + */
7866 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7867 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7874 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7875 name = TREE_OPERAND (t, 1);
7876 if (TREE_CODE (name) == BIT_NOT_EXPR)
7878 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7880 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7882 else if (TREE_CODE (name) == SCOPE_REF
7883 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7885 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7887 name = TREE_OPERAND (name, 1);
7888 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7890 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7891 name = build_nt (SCOPE_REF, base, name);
7893 else if (TREE_CODE (name) == BASELINK)
7894 name = tsubst_baselink (name,
7895 non_reference (TREE_TYPE (object)),
7899 name = tsubst_copy (name, args, complain, in_decl);
7900 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7906 case TRUNC_DIV_EXPR:
7908 case FLOOR_DIV_EXPR:
7909 case ROUND_DIV_EXPR:
7910 case EXACT_DIV_EXPR:
7914 case TRUNC_MOD_EXPR:
7915 case FLOOR_MOD_EXPR:
7916 case TRUTH_ANDIF_EXPR:
7917 case TRUTH_ORIF_EXPR:
7918 case TRUTH_AND_EXPR:
7936 case PREDECREMENT_EXPR:
7937 case PREINCREMENT_EXPR:
7938 case POSTDECREMENT_EXPR:
7939 case POSTINCREMENT_EXPR:
7941 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7942 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7947 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7948 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7949 NULL_TREE, NULL_TREE);
7952 return build_nt (code,
7953 tsubst_copy (TREE_OPERAND (t, 0), args,
7955 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
7961 case PSEUDO_DTOR_EXPR:
7964 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7965 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7966 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7967 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
7974 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7975 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7976 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
7977 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
7984 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7985 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7986 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
7987 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
7991 case TEMPLATE_ID_EXPR:
7993 /* Substituted template arguments */
7994 tree fn = TREE_OPERAND (t, 0);
7995 tree targs = TREE_OPERAND (t, 1);
7997 fn = tsubst_copy (fn, args, complain, in_decl);
7999 targs = tsubst_template_args (targs, args, complain, in_decl);
8001 return lookup_template_function (fn, targs);
8006 tree purpose, value, chain;
8008 if (t == void_list_node)
8011 purpose = TREE_PURPOSE (t);
8013 purpose = tsubst_copy (purpose, args, complain, in_decl);
8014 value = TREE_VALUE (t);
8016 value = tsubst_copy (value, args, complain, in_decl);
8017 chain = TREE_CHAIN (t);
8018 if (chain && chain != void_type_node)
8019 chain = tsubst_copy (chain, args, complain, in_decl);
8020 if (purpose == TREE_PURPOSE (t)
8021 && value == TREE_VALUE (t)
8022 && chain == TREE_CHAIN (t))
8024 return tree_cons (purpose, value, chain);
8031 case TEMPLATE_TYPE_PARM:
8032 case TEMPLATE_TEMPLATE_PARM:
8033 case BOUND_TEMPLATE_TEMPLATE_PARM:
8034 case TEMPLATE_PARM_INDEX:
8036 case REFERENCE_TYPE:
8042 case UNBOUND_CLASS_TEMPLATE:
8045 return tsubst (t, args, complain, in_decl);
8047 case IDENTIFIER_NODE:
8048 if (IDENTIFIER_TYPENAME_P (t))
8050 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8051 return mangle_conv_op_name_for_type (new_type);
8057 /* This is handled by tsubst_copy_and_build. */
8061 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8063 tsubst (TREE_TYPE (t), args, complain, in_decl));
8065 case CLEANUP_POINT_EXPR:
8066 /* We shouldn't have built any of these during initial template
8067 generation. Instead, they should be built during instantiation
8068 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8076 /* Like tsubst_copy for expressions, etc. but also does semantic
8080 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8084 if (t == NULL_TREE || t == error_mark_node)
8087 if (EXPR_HAS_LOCATION (t))
8088 input_location = EXPR_LOCATION (t);
8089 if (STATEMENT_CODE_P (TREE_CODE (t)))
8090 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8092 switch (TREE_CODE (t))
8094 case STATEMENT_LIST:
8096 tree_stmt_iterator i;
8097 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8098 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8102 case CTOR_INITIALIZER:
8103 finish_mem_initializers (tsubst_initializer_list
8104 (TREE_OPERAND (t, 0), args));
8108 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8109 args, complain, in_decl));
8113 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8114 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8115 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8117 finish_expr_stmt (tmp);
8121 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8122 args, complain, in_decl));
8130 decl = DECL_EXPR_DECL (t);
8131 if (TREE_CODE (decl) == LABEL_DECL)
8132 finish_label_decl (DECL_NAME (decl));
8133 else if (TREE_CODE (decl) == USING_DECL)
8135 tree scope = USING_DECL_SCOPE (decl);
8136 tree name = DECL_NAME (decl);
8139 scope = tsubst_expr (scope, args, complain, in_decl);
8140 decl = lookup_qualified_name (scope, name,
8141 /*is_type_p=*/false,
8142 /*complain=*/false);
8143 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8144 qualified_name_lookup_error (scope, name, decl);
8146 do_local_using_decl (decl, scope, name);
8150 init = DECL_INITIAL (decl);
8151 decl = tsubst (decl, args, complain, in_decl);
8152 if (decl != error_mark_node)
8155 DECL_INITIAL (decl) = error_mark_node;
8156 /* By marking the declaration as instantiated, we avoid
8157 trying to instantiate it. Since instantiate_decl can't
8158 handle local variables, and since we've already done
8159 all that needs to be done, that's the right thing to
8161 if (TREE_CODE (decl) == VAR_DECL)
8162 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8163 if (TREE_CODE (decl) == VAR_DECL
8164 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8165 /* Anonymous aggregates are a special case. */
8166 finish_anon_union (decl);
8169 maybe_push_decl (decl);
8170 if (TREE_CODE (decl) == VAR_DECL
8171 && DECL_PRETTY_FUNCTION_P (decl))
8173 /* For __PRETTY_FUNCTION__ we have to adjust the
8175 const char *const name
8176 = cxx_printable_name (current_function_decl, 2);
8177 init = cp_fname_init (name, &TREE_TYPE (decl));
8180 init = tsubst_expr (init, args, complain, in_decl);
8181 cp_finish_decl (decl, init, NULL_TREE, 0);
8186 /* A DECL_EXPR can also be used as an expression, in the condition
8187 clause of an if/for/while construct. */
8192 stmt = begin_for_stmt ();
8193 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8194 finish_for_init_stmt (stmt);
8195 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8196 finish_for_cond (tmp, stmt);
8197 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8198 finish_for_expr (tmp, stmt);
8199 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8200 finish_for_stmt (stmt);
8204 stmt = begin_while_stmt ();
8205 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8206 finish_while_stmt_cond (tmp, stmt);
8207 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8208 finish_while_stmt (stmt);
8212 stmt = begin_do_stmt ();
8213 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8214 finish_do_body (stmt);
8215 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8216 finish_do_stmt (tmp, stmt);
8220 stmt = begin_if_stmt ();
8221 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8222 finish_if_stmt_cond (tmp, stmt);
8223 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8224 finish_then_clause (stmt);
8226 if (ELSE_CLAUSE (t))
8228 begin_else_clause (stmt);
8229 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8230 finish_else_clause (stmt);
8233 finish_if_stmt (stmt);
8237 if (BIND_EXPR_BODY_BLOCK (t))
8238 stmt = begin_function_body ();
8240 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8241 ? BCS_TRY_BLOCK : 0);
8243 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8245 if (BIND_EXPR_BODY_BLOCK (t))
8246 finish_function_body (stmt);
8248 finish_compound_stmt (stmt);
8252 finish_break_stmt ();
8256 finish_continue_stmt ();
8260 stmt = begin_switch_stmt ();
8261 tmp = tsubst_expr (SWITCH_STMT_COND (t), args, complain, in_decl);
8262 finish_switch_cond (tmp, stmt);
8263 tsubst_expr (SWITCH_STMT_BODY (t), args, complain, in_decl);
8264 finish_switch_stmt (stmt);
8267 case CASE_LABEL_EXPR:
8268 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8269 tsubst_expr (CASE_HIGH (t), args, complain,
8274 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8278 tmp = GOTO_DESTINATION (t);
8279 if (TREE_CODE (tmp) != LABEL_DECL)
8280 /* Computed goto's must be tsubst'd into. On the other hand,
8281 non-computed gotos must not be; the identifier in question
8282 will have no binding. */
8283 tmp = tsubst_expr (tmp, args, complain, in_decl);
8285 tmp = DECL_NAME (tmp);
8286 finish_goto_stmt (tmp);
8290 tmp = finish_asm_stmt
8291 (ASM_VOLATILE_P (t),
8292 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8293 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8294 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8295 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8297 tree asm_expr = tmp;
8298 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8299 asm_expr = TREE_OPERAND (asm_expr, 0);
8300 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8307 stmt = begin_try_block ();
8308 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8309 finish_cleanup_try_block (stmt);
8310 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8316 if (FN_TRY_BLOCK_P (t))
8317 stmt = begin_function_try_block ();
8319 stmt = begin_try_block ();
8321 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8323 if (FN_TRY_BLOCK_P (t))
8324 finish_function_try_block (stmt);
8326 finish_try_block (stmt);
8328 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8329 if (FN_TRY_BLOCK_P (t))
8330 finish_function_handler_sequence (stmt);
8332 finish_handler_sequence (stmt);
8340 stmt = begin_handler ();
8341 if (HANDLER_PARMS (t))
8343 decl = HANDLER_PARMS (t);
8344 decl = tsubst (decl, args, complain, in_decl);
8345 /* Prevent instantiate_decl from trying to instantiate
8346 this variable. We've already done all that needs to be
8348 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8352 finish_handler_parms (decl, stmt);
8353 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8354 finish_handler (stmt);
8359 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8363 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8365 return tsubst_copy_and_build (t, args, complain, in_decl,
8366 /*function_p=*/false);
8372 /* T is a postfix-expression that is not being used in a function
8373 call. Return the substituted version of T. */
8376 tsubst_non_call_postfix_expression (tree t, tree args,
8377 tsubst_flags_t complain,
8380 if (TREE_CODE (t) == SCOPE_REF)
8381 t = tsubst_qualified_id (t, args, complain, in_decl,
8382 /*done=*/false, /*address_p=*/false);
8384 t = tsubst_copy_and_build (t, args, complain, in_decl,
8385 /*function_p=*/false);
8390 /* Like tsubst but deals with expressions and performs semantic
8391 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8394 tsubst_copy_and_build (tree t,
8396 tsubst_flags_t complain,
8400 #define RECUR(NODE) \
8401 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8405 if (t == NULL_TREE || t == error_mark_node)
8408 switch (TREE_CODE (t))
8413 case IDENTIFIER_NODE:
8417 tree qualifying_class;
8418 bool non_integral_constant_expression_p;
8419 const char *error_msg;
8421 if (IDENTIFIER_TYPENAME_P (t))
8423 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8424 t = mangle_conv_op_name_for_type (new_type);
8427 /* Look up the name. */
8428 decl = lookup_name (t, 0);
8430 /* By convention, expressions use ERROR_MARK_NODE to indicate
8431 failure, not NULL_TREE. */
8432 if (decl == NULL_TREE)
8433 decl = error_mark_node;
8435 decl = finish_id_expression (t, decl, NULL_TREE,
8438 /*integral_constant_expression_p=*/false,
8439 /*allow_non_integral_constant_expression_p=*/false,
8440 &non_integral_constant_expression_p,
8444 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8445 decl = unqualified_name_lookup_error (decl);
8449 case TEMPLATE_ID_EXPR:
8452 tree template = RECUR (TREE_OPERAND (t, 0));
8453 tree targs = TREE_OPERAND (t, 1);
8456 targs = tsubst_template_args (targs, args, complain, in_decl);
8458 if (TREE_CODE (template) == COMPONENT_REF)
8460 object = TREE_OPERAND (template, 0);
8461 template = TREE_OPERAND (template, 1);
8465 template = lookup_template_function (template, targs);
8468 return build3 (COMPONENT_REF, TREE_TYPE (template),
8469 object, template, NULL_TREE);
8476 tree r = RECUR (TREE_OPERAND (t, 0));
8478 if (REFERENCE_REF_P (t))
8480 /* A type conversion to reference type will be enclosed in
8481 such an indirect ref, but the substitution of the cast
8482 will have also added such an indirect ref. */
8483 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8484 r = convert_from_reference (r);
8487 r = build_x_indirect_ref (r, "unary *");
8493 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8494 RECUR (TREE_OPERAND (t, 0)));
8497 return build_functional_cast
8498 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8499 RECUR (TREE_OPERAND (t, 0)));
8501 case REINTERPRET_CAST_EXPR:
8502 return build_reinterpret_cast
8503 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8504 RECUR (TREE_OPERAND (t, 0)));
8506 case CONST_CAST_EXPR:
8507 return build_const_cast
8508 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8509 RECUR (TREE_OPERAND (t, 0)));
8511 case DYNAMIC_CAST_EXPR:
8512 return build_dynamic_cast
8513 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8514 RECUR (TREE_OPERAND (t, 0)));
8516 case STATIC_CAST_EXPR:
8517 return build_static_cast
8518 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8519 RECUR (TREE_OPERAND (t, 0)));
8521 case POSTDECREMENT_EXPR:
8522 case POSTINCREMENT_EXPR:
8523 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8524 args, complain, in_decl);
8525 return build_x_unary_op (TREE_CODE (t), op1);
8527 case PREDECREMENT_EXPR:
8528 case PREINCREMENT_EXPR:
8532 case TRUTH_NOT_EXPR:
8533 case UNARY_PLUS_EXPR: /* Unary + */
8536 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8539 op1 = TREE_OPERAND (t, 0);
8540 if (TREE_CODE (op1) == SCOPE_REF)
8541 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8542 /*done=*/true, /*address_p=*/true);
8544 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8546 if (TREE_CODE (op1) == LABEL_DECL)
8547 return finish_label_address_expr (DECL_NAME (op1));
8548 return build_x_unary_op (ADDR_EXPR, op1);
8553 case TRUNC_DIV_EXPR:
8555 case FLOOR_DIV_EXPR:
8556 case ROUND_DIV_EXPR:
8557 case EXACT_DIV_EXPR:
8561 case TRUNC_MOD_EXPR:
8562 case FLOOR_MOD_EXPR:
8563 case TRUTH_ANDIF_EXPR:
8564 case TRUTH_ORIF_EXPR:
8565 case TRUTH_AND_EXPR:
8581 return build_x_binary_op
8583 RECUR (TREE_OPERAND (t, 0)),
8584 RECUR (TREE_OPERAND (t, 1)),
8585 /*overloaded_p=*/NULL);
8588 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8589 /*address_p=*/false);
8591 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8592 args, complain, in_decl);
8593 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8594 /*overloaded_p=*/NULL);
8598 op1 = TREE_OPERAND (t, 0);
8601 /* When there are no ARGS, we are trying to evaluate a
8602 non-dependent expression from the parser. Trying to do
8603 the substitutions may not work. */
8605 op1 = TREE_TYPE (op1);
8614 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8616 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8620 tree r = build_x_modify_expr
8621 (RECUR (TREE_OPERAND (t, 0)),
8622 TREE_CODE (TREE_OPERAND (t, 1)),
8623 RECUR (TREE_OPERAND (t, 2)));
8624 /* TREE_NO_WARNING must be set if either the expression was
8625 parenthesized or it uses an operator such as >>= rather
8626 than plain assignment. In the former case, it was already
8627 set and must be copied. In the latter case,
8628 build_x_modify_expr sets it and it must not be reset
8630 if (TREE_NO_WARNING (t))
8631 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8636 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8637 args, complain, in_decl);
8638 /* Remember that there was a reference to this entity. */
8641 return build_x_arrow (op1);
8645 (RECUR (TREE_OPERAND (t, 0)),
8646 RECUR (TREE_OPERAND (t, 1)),
8647 RECUR (TREE_OPERAND (t, 2)),
8648 RECUR (TREE_OPERAND (t, 3)),
8649 NEW_EXPR_USE_GLOBAL (t));
8652 return delete_sanity
8653 (RECUR (TREE_OPERAND (t, 0)),
8654 RECUR (TREE_OPERAND (t, 1)),
8655 DELETE_EXPR_USE_VEC (t),
8656 DELETE_EXPR_USE_GLOBAL (t));
8659 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8660 RECUR (TREE_OPERAND (t, 1)));
8669 function = TREE_OPERAND (t, 0);
8670 /* When we parsed the expression, we determined whether or
8671 not Koenig lookup should be performed. */
8672 koenig_p = KOENIG_LOOKUP_P (t);
8673 if (TREE_CODE (function) == SCOPE_REF)
8676 function = tsubst_qualified_id (function, args, complain, in_decl,
8678 /*address_p=*/false);
8682 qualified_p = (TREE_CODE (function) == COMPONENT_REF
8683 && (TREE_CODE (TREE_OPERAND (function, 1))
8685 function = tsubst_copy_and_build (function, args, complain,
8688 if (BASELINK_P (function))
8692 call_args = RECUR (TREE_OPERAND (t, 1));
8694 /* We do not perform argument-dependent lookup if normal
8695 lookup finds a non-function, in accordance with the
8696 expected resolution of DR 218. */
8698 && ((is_overloaded_fn (function)
8699 /* If lookup found a member function, the Koenig lookup is
8700 not appropriate, even if an unqualified-name was used
8701 to denote the function. */
8702 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8703 || TREE_CODE (function) == IDENTIFIER_NODE))
8704 function = perform_koenig_lookup (function, call_args);
8706 if (TREE_CODE (function) == IDENTIFIER_NODE)
8708 unqualified_name_lookup_error (function);
8709 return error_mark_node;
8712 /* Remember that there was a reference to this entity. */
8713 if (DECL_P (function))
8714 mark_used (function);
8716 if (TREE_CODE (function) == OFFSET_REF)
8717 return build_offset_ref_call_from_tree (function, call_args);
8718 if (TREE_CODE (function) == COMPONENT_REF)
8720 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8721 return finish_call_expr (function, call_args,
8722 /*disallow_virtual=*/false,
8723 /*koenig_p=*/false);
8725 return (build_new_method_call
8726 (TREE_OPERAND (function, 0),
8727 TREE_OPERAND (function, 1),
8728 call_args, NULL_TREE,
8729 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8731 return finish_call_expr (function, call_args,
8732 /*disallow_virtual=*/qualified_p,
8737 return build_x_conditional_expr
8738 (RECUR (TREE_OPERAND (t, 0)),
8739 RECUR (TREE_OPERAND (t, 1)),
8740 RECUR (TREE_OPERAND (t, 2)));
8742 case PSEUDO_DTOR_EXPR:
8743 return finish_pseudo_destructor_expr
8744 (RECUR (TREE_OPERAND (t, 0)),
8745 RECUR (TREE_OPERAND (t, 1)),
8746 RECUR (TREE_OPERAND (t, 2)));
8750 tree purpose, value, chain;
8752 if (t == void_list_node)
8755 purpose = TREE_PURPOSE (t);
8757 purpose = RECUR (purpose);
8758 value = TREE_VALUE (t);
8760 value = RECUR (value);
8761 chain = TREE_CHAIN (t);
8762 if (chain && chain != void_type_node)
8763 chain = RECUR (chain);
8764 if (purpose == TREE_PURPOSE (t)
8765 && value == TREE_VALUE (t)
8766 && chain == TREE_CHAIN (t))
8768 return tree_cons (purpose, value, chain);
8776 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8777 args, complain, in_decl);
8778 /* Remember that there was a reference to this entity. */
8779 if (DECL_P (object))
8782 member = TREE_OPERAND (t, 1);
8783 if (BASELINK_P (member))
8784 member = tsubst_baselink (member,
8785 non_reference (TREE_TYPE (object)),
8786 args, complain, in_decl);
8788 member = tsubst_copy (member, args, complain, in_decl);
8790 if (member == error_mark_node)
8791 return error_mark_node;
8792 else if (!CLASS_TYPE_P (TREE_TYPE (object)))
8794 if (TREE_CODE (member) == BIT_NOT_EXPR)
8795 return finish_pseudo_destructor_expr (object,
8797 TREE_TYPE (object));
8798 else if (TREE_CODE (member) == SCOPE_REF
8799 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8800 return finish_pseudo_destructor_expr (object,
8802 TREE_TYPE (object));
8804 else if (TREE_CODE (member) == SCOPE_REF
8805 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8810 /* Lookup the template functions now that we know what the
8812 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8813 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8814 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8815 /*is_type_p=*/false,
8816 /*complain=*/false);
8817 if (BASELINK_P (member))
8819 BASELINK_FUNCTIONS (member)
8820 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8822 member = (adjust_result_of_qualified_name_lookup
8823 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8824 TREE_TYPE (object)));
8828 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8830 return error_mark_node;
8833 else if (TREE_CODE (member) == SCOPE_REF
8834 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8835 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8837 if (complain & tf_error)
8839 if (TYPE_P (TREE_OPERAND (member, 0)))
8840 error ("%qT is not a class or namespace",
8841 TREE_OPERAND (member, 0));
8843 error ("%qD is not a class or namespace",
8844 TREE_OPERAND (member, 0));
8846 return error_mark_node;
8848 else if (TREE_CODE (member) == FIELD_DECL)
8849 return finish_non_static_data_member (member, object, NULL_TREE);
8851 return finish_class_member_access_expr (object, member);
8856 (RECUR (TREE_OPERAND (t, 0)));
8860 VEC(constructor_elt,gc) *n;
8861 constructor_elt *ce;
8862 unsigned HOST_WIDE_INT idx;
8864 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8865 bool process_index_p;
8867 /* digest_init will do the wrong thing if we let it. */
8868 if (type && TYPE_PTRMEMFUNC_P (type))
8871 /* We do not want to process the index of aggregate
8872 initializers as they are identifier nodes which will be
8873 looked up by digest_init. */
8874 process_index_p = !(type && IS_AGGR_TYPE (type));
8876 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
8877 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
8879 if (ce->index && process_index_p)
8880 ce->index = RECUR (ce->index);
8881 ce->value = RECUR (ce->value);
8884 r = build_constructor (NULL_TREE, n);
8885 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8888 return digest_init (type, r);
8894 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8895 if (TYPE_P (operand_0))
8896 return get_typeid (operand_0);
8897 return build_typeid (operand_0);
8907 tree r = tsubst_copy (t, args, complain, in_decl);
8909 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
8910 /* If the original type was a reference, we'll be wrapped in
8911 the appropriate INDIRECT_REF. */
8912 r = convert_from_reference (r);
8917 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8918 tsubst_copy (TREE_TYPE (t), args, complain,
8922 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8926 tree old_stmt_expr = cur_stmt_expr;
8927 tree stmt_expr = begin_stmt_expr ();
8929 cur_stmt_expr = stmt_expr;
8930 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8931 stmt_expr = finish_stmt_expr (stmt_expr, false);
8932 cur_stmt_expr = old_stmt_expr;
8938 t = tsubst_copy (t, args, complain, in_decl);
8939 /* As in finish_id_expression, we resolve enumeration constants
8940 to their underlying values. */
8941 if (TREE_CODE (t) == CONST_DECL)
8942 return DECL_INITIAL (t);
8946 /* Handle Objective-C++ constructs, if appropriate. */
8949 = objcp_tsubst_copy_and_build (t, args, complain,
8950 in_decl, /*function_p=*/false);
8954 return tsubst_copy (t, args, complain, in_decl);
8960 /* Verify that the instantiated ARGS are valid. For type arguments,
8961 make sure that the type's linkage is ok. For non-type arguments,
8962 make sure they are constants if they are integral or enumerations.
8963 Emit an error under control of COMPLAIN, and return TRUE on error. */
8966 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
8968 int ix, len = DECL_NTPARMS (tmpl);
8969 bool result = false;
8971 for (ix = 0; ix != len; ix++)
8973 tree t = TREE_VEC_ELT (args, ix);
8977 /* [basic.link]: A name with no linkage (notably, the name
8978 of a class or enumeration declared in a local scope)
8979 shall not be used to declare an entity with linkage.
8980 This implies that names with no linkage cannot be used as
8981 template arguments. */
8982 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
8986 /* DR 488 makes use of a type with no linkage causes
8987 type deduction to fail. */
8988 if (complain & tf_error)
8990 if (TYPE_ANONYMOUS_P (nt))
8991 error ("%qT is/uses anonymous type", t);
8993 error ("%qT uses local type %qT", t, nt);
8997 /* In order to avoid all sorts of complications, we do not
8998 allow variably-modified types as template arguments. */
8999 else if (variably_modified_type_p (t, NULL_TREE))
9001 if (complain & tf_error)
9002 error ("%qT is a variably modified type", t);
9006 /* A non-type argument of integral or enumerated type must be a
9008 else if (TREE_TYPE (t)
9009 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
9010 && !TREE_CONSTANT (t))
9012 if (complain & tf_error)
9013 error ("integral expression %qE is not constant", t);
9017 if (result && (complain & tf_error))
9018 error (" trying to instantiate %qD", tmpl);
9022 /* Instantiate the indicated variable or function template TMPL with
9023 the template arguments in TARG_PTR. */
9026 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
9032 if (tmpl == error_mark_node)
9033 return error_mark_node;
9035 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
9037 /* If this function is a clone, handle it specially. */
9038 if (DECL_CLONED_FUNCTION_P (tmpl))
9043 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
9045 if (spec == error_mark_node)
9046 return error_mark_node;
9048 /* Look for the clone. */
9049 FOR_EACH_CLONE (clone, spec)
9050 if (DECL_NAME (clone) == DECL_NAME (tmpl))
9052 /* We should always have found the clone by now. */
9057 /* Check to see if we already have this specialization. */
9058 spec = retrieve_specialization (tmpl, targ_ptr,
9059 /*class_specializations_p=*/false);
9060 if (spec != NULL_TREE)
9063 gen_tmpl = most_general_template (tmpl);
9064 if (tmpl != gen_tmpl)
9066 /* The TMPL is a partial instantiation. To get a full set of
9067 arguments we must add the arguments used to perform the
9068 partial instantiation. */
9069 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9072 /* Check to see if we already have this specialization. */
9073 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9074 /*class_specializations_p=*/false);
9075 if (spec != NULL_TREE)
9079 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9081 return error_mark_node;
9083 /* We are building a FUNCTION_DECL, during which the access of its
9084 parameters and return types have to be checked. However this
9085 FUNCTION_DECL which is the desired context for access checking
9086 is not built yet. We solve this chicken-and-egg problem by
9087 deferring all checks until we have the FUNCTION_DECL. */
9088 push_deferring_access_checks (dk_deferred);
9090 /* Substitute template parameters. */
9091 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9092 targ_ptr, complain, gen_tmpl);
9094 /* Now we know the specialization, compute access previously
9096 push_access_scope (fndecl);
9097 perform_deferred_access_checks ();
9098 pop_access_scope (fndecl);
9099 pop_deferring_access_checks ();
9101 /* The DECL_TI_TEMPLATE should always be the immediate parent
9102 template, not the most general template. */
9103 DECL_TI_TEMPLATE (fndecl) = tmpl;
9105 /* If we've just instantiated the main entry point for a function,
9106 instantiate all the alternate entry points as well. We do this
9107 by cloning the instantiation of the main entry point, not by
9108 instantiating the template clones. */
9109 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9110 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9115 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9116 arguments that are being used when calling it. TARGS is a vector
9117 into which the deduced template arguments are placed.
9119 Return zero for success, 2 for an incomplete match that doesn't resolve
9120 all the types, and 1 for complete failure. An error message will be
9121 printed only for an incomplete match.
9123 If FN is a conversion operator, or we are trying to produce a specific
9124 specialization, RETURN_TYPE is the return type desired.
9126 The EXPLICIT_TARGS are explicit template arguments provided via a
9129 The parameter STRICT is one of:
9132 We are deducing arguments for a function call, as in
9136 We are deducing arguments for a conversion function, as in
9140 We are deducing arguments when doing an explicit instantiation
9141 as in [temp.explicit], when determining an explicit specialization
9142 as in [temp.expl.spec], or when taking the address of a function
9143 template, as in [temp.deduct.funcaddr]. */
9146 fn_type_unification (tree fn,
9147 tree explicit_targs,
9151 unification_kind_t strict,
9158 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9160 fntype = TREE_TYPE (fn);
9165 The specified template arguments must match the template
9166 parameters in kind (i.e., type, nontype, template), and there
9167 must not be more arguments than there are parameters;
9168 otherwise type deduction fails.
9170 Nontype arguments must match the types of the corresponding
9171 nontype template parameters, or must be convertible to the
9172 types of the corresponding nontype parameters as specified in
9173 _temp.arg.nontype_, otherwise type deduction fails.
9175 All references in the function type of the function template
9176 to the corresponding template parameters are replaced by the
9177 specified template argument values. If a substitution in a
9178 template parameter or in the function type of the function
9179 template results in an invalid type, type deduction fails. */
9181 tree converted_args;
9184 if (explicit_targs == error_mark_node)
9188 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9189 explicit_targs, NULL_TREE, tf_none,
9190 /*require_all_arguments=*/0));
9191 if (converted_args == error_mark_node)
9194 /* Substitute the explicit args into the function type. This is
9195 necessary so that, for instance, explicitly declared function
9196 arguments can match null pointed constants. If we were given
9197 an incomplete set of explicit args, we must not do semantic
9198 processing during substitution as we could create partial
9200 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9201 processing_template_decl += incomplete;
9202 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9203 processing_template_decl -= incomplete;
9205 if (fntype == error_mark_node)
9208 /* Place the explicitly specified arguments in TARGS. */
9209 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9210 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9213 parms = TYPE_ARG_TYPES (fntype);
9214 /* Never do unification on the 'this' parameter. */
9215 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9216 parms = TREE_CHAIN (parms);
9220 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9221 args = tree_cons (NULL_TREE, return_type, args);
9224 /* We allow incomplete unification without an error message here
9225 because the standard doesn't seem to explicitly prohibit it. Our
9226 callers must be ready to deal with unification failures in any
9228 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9229 targs, parms, args, /*subr=*/0,
9233 /* All is well so far. Now, check:
9237 When all template arguments have been deduced, all uses of
9238 template parameters in nondeduced contexts are replaced with
9239 the corresponding deduced argument values. If the
9240 substitution results in an invalid type, as described above,
9241 type deduction fails. */
9242 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9249 /* Adjust types before performing type deduction, as described in
9250 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9251 sections are symmetric. PARM is the type of a function parameter
9252 or the return type of the conversion function. ARG is the type of
9253 the argument passed to the call, or the type of the value
9254 initialized with the result of the conversion function. */
9257 maybe_adjust_types_for_deduction (unification_kind_t strict,
9270 /* Swap PARM and ARG throughout the remainder of this
9271 function; the handling is precisely symmetric since PARM
9272 will initialize ARG rather than vice versa. */
9280 /* There is nothing to do in this case. */
9287 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9289 /* [temp.deduct.call]
9291 If P is not a reference type:
9293 --If A is an array type, the pointer type produced by the
9294 array-to-pointer standard conversion (_conv.array_) is
9295 used in place of A for type deduction; otherwise,
9297 --If A is a function type, the pointer type produced by
9298 the function-to-pointer standard conversion
9299 (_conv.func_) is used in place of A for type deduction;
9302 --If A is a cv-qualified type, the top level
9303 cv-qualifiers of A's type are ignored for type
9305 if (TREE_CODE (*arg) == ARRAY_TYPE)
9306 *arg = build_pointer_type (TREE_TYPE (*arg));
9307 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9308 *arg = build_pointer_type (*arg);
9310 *arg = TYPE_MAIN_VARIANT (*arg);
9313 /* [temp.deduct.call]
9315 If P is a cv-qualified type, the top level cv-qualifiers
9316 of P's type are ignored for type deduction. If P is a
9317 reference type, the type referred to by P is used for
9319 *parm = TYPE_MAIN_VARIANT (*parm);
9320 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9322 *parm = TREE_TYPE (*parm);
9323 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9326 /* DR 322. For conversion deduction, remove a reference type on parm
9327 too (which has been swapped into ARG). */
9328 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9329 *arg = TREE_TYPE (*arg);
9334 /* Most parms like fn_type_unification.
9336 If SUBR is 1, we're being called recursively (to unify the
9337 arguments of a function or method parameter of a function
9341 type_unification_real (tree tparms,
9346 unification_kind_t strict,
9351 int ntparms = TREE_VEC_LENGTH (tparms);
9353 int saw_undeduced = 0;
9356 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9357 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9358 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9359 gcc_assert (ntparms > 0);
9364 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9365 | UNIFY_ALLOW_DERIVED);
9369 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9373 sub_strict = UNIFY_ALLOW_NONE;
9384 while (parms && parms != void_list_node
9385 && args && args != void_list_node)
9387 parm = TREE_VALUE (parms);
9388 parms = TREE_CHAIN (parms);
9389 arg = TREE_VALUE (args);
9390 args = TREE_CHAIN (args);
9392 if (arg == error_mark_node)
9394 if (arg == unknown_type_node)
9395 /* We can't deduce anything from this, but we might get all the
9396 template args from other function args. */
9399 /* Conversions will be performed on a function argument that
9400 corresponds with a function parameter that contains only
9401 non-deducible template parameters and explicitly specified
9402 template parameters. */
9403 if (!uses_template_parms (parm))
9408 type = TREE_TYPE (arg);
9412 if (same_type_p (parm, type))
9414 if (strict != DEDUCE_EXACT
9415 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
9424 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9425 if (type_unknown_p (arg))
9427 /* [temp.deduct.type] A template-argument can be deduced from
9428 a pointer to function or pointer to member function
9429 argument if the set of overloaded functions does not
9430 contain function templates and at most one of a set of
9431 overloaded functions provides a unique match. */
9433 if (resolve_overloaded_unification
9434 (tparms, targs, parm, arg, strict, sub_strict)
9439 arg = TREE_TYPE (arg);
9440 if (arg == error_mark_node)
9445 int arg_strict = sub_strict;
9448 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9450 if (unify (tparms, targs, parm, arg, arg_strict))
9455 /* Fail if we've reached the end of the parm list, and more args
9456 are present, and the parm list isn't variadic. */
9457 if (args && args != void_list_node && parms == void_list_node)
9459 /* Fail if parms are left and they don't have default values. */
9460 if (parms && parms != void_list_node
9461 && TREE_PURPOSE (parms) == NULL_TREE)
9465 for (i = 0; i < ntparms; i++)
9466 if (!TREE_VEC_ELT (targs, i))
9468 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9470 /* If this is an undeduced nontype parameter that depends on
9471 a type parameter, try another pass; its type may have been
9472 deduced from a later argument than the one from which
9473 this parameter can be deduced. */
9474 if (TREE_CODE (tparm) == PARM_DECL
9475 && uses_template_parms (TREE_TYPE (tparm))
9476 && !saw_undeduced++)
9485 /* Subroutine of type_unification_real. Args are like the variables at the
9486 call site. ARG is an overloaded function (or template-id); we try
9487 deducing template args from each of the overloads, and if only one
9488 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9491 resolve_overloaded_unification (tree tparms,
9495 unification_kind_t strict,
9498 tree tempargs = copy_node (targs);
9502 if (TREE_CODE (arg) == ADDR_EXPR)
9504 arg = TREE_OPERAND (arg, 0);
9510 if (TREE_CODE (arg) == COMPONENT_REF)
9511 /* Handle `&x' where `x' is some static or non-static member
9513 arg = TREE_OPERAND (arg, 1);
9515 if (TREE_CODE (arg) == OFFSET_REF)
9516 arg = TREE_OPERAND (arg, 1);
9518 /* Strip baselink information. */
9519 if (BASELINK_P (arg))
9520 arg = BASELINK_FUNCTIONS (arg);
9522 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9524 /* If we got some explicit template args, we need to plug them into
9525 the affected templates before we try to unify, in case the
9526 explicit args will completely resolve the templates in question. */
9528 tree expl_subargs = TREE_OPERAND (arg, 1);
9529 arg = TREE_OPERAND (arg, 0);
9531 for (; arg; arg = OVL_NEXT (arg))
9533 tree fn = OVL_CURRENT (arg);
9536 if (TREE_CODE (fn) != TEMPLATE_DECL)
9539 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
9540 expl_subargs, /*check_ret=*/false);
9543 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9544 good += try_one_overload (tparms, targs, tempargs, parm,
9545 elem, strict, sub_strict, addr_p);
9551 gcc_assert (TREE_CODE (arg) == OVERLOAD
9552 || TREE_CODE (arg) == FUNCTION_DECL);
9554 for (; arg; arg = OVL_NEXT (arg))
9555 good += try_one_overload (tparms, targs, tempargs, parm,
9556 TREE_TYPE (OVL_CURRENT (arg)),
9557 strict, sub_strict, addr_p);
9560 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9561 to function or pointer to member function argument if the set of
9562 overloaded functions does not contain function templates and at most
9563 one of a set of overloaded functions provides a unique match.
9565 So if we found multiple possibilities, we return success but don't
9570 int i = TREE_VEC_LENGTH (targs);
9572 if (TREE_VEC_ELT (tempargs, i))
9573 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9581 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9582 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9583 different overloads deduce different arguments for a given parm.
9584 ADDR_P is true if the expression for which deduction is being
9585 performed was of the form "& fn" rather than simply "fn".
9587 Returns 1 on success. */
9590 try_one_overload (tree tparms,
9595 unification_kind_t strict,
9603 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9604 to function or pointer to member function argument if the set of
9605 overloaded functions does not contain function templates and at most
9606 one of a set of overloaded functions provides a unique match.
9608 So if this is a template, just return success. */
9610 if (uses_template_parms (arg))
9613 if (TREE_CODE (arg) == METHOD_TYPE)
9614 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9616 arg = build_pointer_type (arg);
9618 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9620 /* We don't copy orig_targs for this because if we have already deduced
9621 some template args from previous args, unify would complain when we
9622 try to deduce a template parameter for the same argument, even though
9623 there isn't really a conflict. */
9624 nargs = TREE_VEC_LENGTH (targs);
9625 tempargs = make_tree_vec (nargs);
9627 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9630 /* First make sure we didn't deduce anything that conflicts with
9631 explicitly specified args. */
9632 for (i = nargs; i--; )
9634 tree elt = TREE_VEC_ELT (tempargs, i);
9635 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9639 else if (uses_template_parms (elt))
9640 /* Since we're unifying against ourselves, we will fill in
9641 template args used in the function parm list with our own
9642 template parms. Discard them. */
9643 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9644 else if (oldelt && !template_args_equal (oldelt, elt))
9648 for (i = nargs; i--; )
9650 tree elt = TREE_VEC_ELT (tempargs, i);
9653 TREE_VEC_ELT (targs, i) = elt;
9659 /* Verify that nondeduce template argument agrees with the type
9660 obtained from argument deduction. Return nonzero if the
9665 struct A { typedef int X; };
9666 template <class T, class U> struct C {};
9667 template <class T> struct C<T, typename T::X> {};
9669 Then with the instantiation `C<A, int>', we can deduce that
9670 `T' is `A' but unify () does not check whether `typename T::X'
9671 is `int'. This function ensure that they agree.
9673 TARGS, PARMS are the same as the arguments of unify.
9674 ARGS contains template arguments from all levels. */
9677 verify_class_unification (tree targs, tree parms, tree args)
9679 parms = tsubst (parms, add_outermost_template_args (args, targs),
9680 tf_none, NULL_TREE);
9681 if (parms == error_mark_node)
9684 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9687 /* PARM is a template class (perhaps with unbound template
9688 parameters). ARG is a fully instantiated type. If ARG can be
9689 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9690 TARGS are as for unify. */
9693 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9697 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9698 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9699 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9702 /* We need to make a new template argument vector for the call to
9703 unify. If we used TARGS, we'd clutter it up with the result of
9704 the attempted unification, even if this class didn't work out.
9705 We also don't want to commit ourselves to all the unifications
9706 we've already done, since unification is supposed to be done on
9707 an argument-by-argument basis. In other words, consider the
9708 following pathological case:
9710 template <int I, int J, int K>
9713 template <int I, int J>
9714 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9716 template <int I, int J, int K>
9717 void f(S<I, J, K>, S<I, I, I>);
9726 Now, by the time we consider the unification involving `s2', we
9727 already know that we must have `f<0, 0, 0>'. But, even though
9728 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9729 because there are two ways to unify base classes of S<0, 1, 2>
9730 with S<I, I, I>. If we kept the already deduced knowledge, we
9731 would reject the possibility I=1. */
9732 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9734 /* If unification failed, we're done. */
9735 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9736 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9742 /* Given a template type PARM and a class type ARG, find the unique
9743 base type in ARG that is an instance of PARM. We do not examine
9744 ARG itself; only its base-classes. If there is not exactly one
9745 appropriate base class, return NULL_TREE. PARM may be the type of
9746 a partial specialization, as well as a plain template type. Used
9750 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9752 tree rval = NULL_TREE;
9755 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9757 binfo = TYPE_BINFO (complete_type (arg));
9759 /* The type could not be completed. */
9762 /* Walk in inheritance graph order. The search order is not
9763 important, and this avoids multiple walks of virtual bases. */
9764 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9766 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9770 /* If there is more than one satisfactory baseclass, then:
9774 If they yield more than one possible deduced A, the type
9778 if (rval && !same_type_p (r, rval))
9788 /* Returns the level of DECL, which declares a template parameter. */
9791 template_decl_level (tree decl)
9793 switch (TREE_CODE (decl))
9797 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9800 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9808 /* Decide whether ARG can be unified with PARM, considering only the
9809 cv-qualifiers of each type, given STRICT as documented for unify.
9810 Returns nonzero iff the unification is OK on that basis. */
9813 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9815 int arg_quals = cp_type_quals (arg);
9816 int parm_quals = cp_type_quals (parm);
9818 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9819 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9821 /* Although a CVR qualifier is ignored when being applied to a
9822 substituted template parameter ([8.3.2]/1 for example), that
9823 does not apply during deduction [14.8.2.4]/1, (even though
9824 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9825 this). Except when we're allowing additional CV qualifiers
9826 at the outer level [14.8.2.1]/3,1st bullet. */
9827 if ((TREE_CODE (arg) == REFERENCE_TYPE
9828 || TREE_CODE (arg) == FUNCTION_TYPE
9829 || TREE_CODE (arg) == METHOD_TYPE)
9830 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9833 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9834 && (parm_quals & TYPE_QUAL_RESTRICT))
9838 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9839 && (arg_quals & parm_quals) != parm_quals)
9842 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9843 && (parm_quals & arg_quals) != arg_quals)
9849 /* Takes parameters as for type_unification. Returns 0 if the
9850 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9851 bitwise or of the following flags:
9854 Require an exact match between PARM and ARG.
9855 UNIFY_ALLOW_MORE_CV_QUAL:
9856 Allow the deduced ARG to be more cv-qualified (by qualification
9857 conversion) than ARG.
9858 UNIFY_ALLOW_LESS_CV_QUAL:
9859 Allow the deduced ARG to be less cv-qualified than ARG.
9860 UNIFY_ALLOW_DERIVED:
9861 Allow the deduced ARG to be a template base class of ARG,
9862 or a pointer to a template base class of the type pointed to by
9864 UNIFY_ALLOW_INTEGER:
9865 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9866 case for more information.
9867 UNIFY_ALLOW_OUTER_LEVEL:
9868 This is the outermost level of a deduction. Used to determine validity
9869 of qualification conversions. A valid qualification conversion must
9870 have const qualified pointers leading up to the inner type which
9871 requires additional CV quals, except at the outer level, where const
9872 is not required [conv.qual]. It would be normal to set this flag in
9873 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9874 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9875 This is the outermost level of a deduction, and PARM can be more CV
9876 qualified at this point.
9877 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9878 This is the outermost level of a deduction, and PARM can be less CV
9879 qualified at this point. */
9882 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9887 int strict_in = strict;
9889 /* I don't think this will do the right thing with respect to types.
9890 But the only case I've seen it in so far has been array bounds, where
9891 signedness is the only information lost, and I think that will be
9893 while (TREE_CODE (parm) == NOP_EXPR)
9894 parm = TREE_OPERAND (parm, 0);
9896 if (arg == error_mark_node)
9898 if (arg == unknown_type_node)
9899 /* We can't deduce anything from this, but we might get all the
9900 template args from other function args. */
9903 /* If PARM uses template parameters, then we can't bail out here,
9904 even if ARG == PARM, since we won't record unifications for the
9905 template parameters. We might need them if we're trying to
9906 figure out which of two things is more specialized. */
9907 if (arg == parm && !uses_template_parms (parm))
9910 /* Immediately reject some pairs that won't unify because of
9911 cv-qualification mismatches. */
9912 if (TREE_CODE (arg) == TREE_CODE (parm)
9914 /* It is the elements of the array which hold the cv quals of an array
9915 type, and the elements might be template type parms. We'll check
9917 && TREE_CODE (arg) != ARRAY_TYPE
9918 /* We check the cv-qualifiers when unifying with template type
9919 parameters below. We want to allow ARG `const T' to unify with
9920 PARM `T' for example, when computing which of two templates
9921 is more specialized, for example. */
9922 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9923 && !check_cv_quals_for_unify (strict_in, arg, parm))
9926 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9927 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9928 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9929 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9930 strict &= ~UNIFY_ALLOW_DERIVED;
9931 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9932 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9934 switch (TREE_CODE (parm))
9938 case UNBOUND_CLASS_TEMPLATE:
9939 /* In a type which contains a nested-name-specifier, template
9940 argument values cannot be deduced for template parameters used
9941 within the nested-name-specifier. */
9944 case TEMPLATE_TYPE_PARM:
9945 case TEMPLATE_TEMPLATE_PARM:
9946 case BOUND_TEMPLATE_TEMPLATE_PARM:
9947 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
9949 if (TEMPLATE_TYPE_LEVEL (parm)
9950 != template_decl_level (tparm))
9951 /* The PARM is not one we're trying to unify. Just check
9952 to see if it matches ARG. */
9953 return (TREE_CODE (arg) == TREE_CODE (parm)
9954 && same_type_p (parm, arg)) ? 0 : 1;
9955 idx = TEMPLATE_TYPE_IDX (parm);
9956 targ = TREE_VEC_ELT (targs, idx);
9957 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
9959 /* Check for mixed types and values. */
9960 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9961 && TREE_CODE (tparm) != TYPE_DECL)
9962 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
9963 && TREE_CODE (tparm) != TEMPLATE_DECL))
9966 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
9968 /* ARG must be constructed from a template class or a template
9969 template parameter. */
9970 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
9971 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
9975 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
9976 tree parmvec = TYPE_TI_ARGS (parm);
9977 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
9979 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
9982 /* The parameter and argument roles have to be switched here
9983 in order to handle default arguments properly. For example,
9984 template<template <class> class TT> void f(TT<int>)
9985 should be able to accept vector<int> which comes from
9986 template <class T, class Allocator = allocator>
9989 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
9993 /* Deduce arguments T, i from TT<T> or TT<i>.
9994 We check each element of PARMVEC and ARGVEC individually
9995 rather than the whole TREE_VEC since they can have
9996 different number of elements. */
9998 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
10000 if (unify (tparms, targs,
10001 TREE_VEC_ELT (parmvec, i),
10002 TREE_VEC_ELT (argvec, i),
10007 arg = TYPE_TI_TEMPLATE (arg);
10009 /* Fall through to deduce template name. */
10012 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10013 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10015 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
10017 /* Simple cases: Value already set, does match or doesn't. */
10018 if (targ != NULL_TREE && template_args_equal (targ, arg))
10025 /* If PARM is `const T' and ARG is only `int', we don't have
10026 a match unless we are allowing additional qualification.
10027 If ARG is `const int' and PARM is just `T' that's OK;
10028 that binds `const int' to `T'. */
10029 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10033 /* Consider the case where ARG is `const volatile int' and
10034 PARM is `const T'. Then, T should be `volatile int'. */
10035 arg = cp_build_qualified_type_real
10036 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10037 if (arg == error_mark_node)
10040 /* Simple cases: Value already set, does match or doesn't. */
10041 if (targ != NULL_TREE && same_type_p (targ, arg))
10046 /* Make sure that ARG is not a variable-sized array. (Note
10047 that were talking about variable-sized arrays (like
10048 `int[n]'), rather than arrays of unknown size (like
10049 `int[]').) We'll get very confused by such a type since
10050 the bound of the array will not be computable in an
10051 instantiation. Besides, such types are not allowed in
10052 ISO C++, so we can do as we please here. */
10053 if (variably_modified_type_p (arg, NULL_TREE))
10057 TREE_VEC_ELT (targs, idx) = arg;
10060 case TEMPLATE_PARM_INDEX:
10061 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10063 if (TEMPLATE_PARM_LEVEL (parm)
10064 != template_decl_level (tparm))
10065 /* The PARM is not one we're trying to unify. Just check
10066 to see if it matches ARG. */
10067 return !(TREE_CODE (arg) == TREE_CODE (parm)
10068 && cp_tree_equal (parm, arg));
10070 idx = TEMPLATE_PARM_IDX (parm);
10071 targ = TREE_VEC_ELT (targs, idx);
10074 return !cp_tree_equal (targ, arg);
10076 /* [temp.deduct.type] If, in the declaration of a function template
10077 with a non-type template-parameter, the non-type
10078 template-parameter is used in an expression in the function
10079 parameter-list and, if the corresponding template-argument is
10080 deduced, the template-argument type shall match the type of the
10081 template-parameter exactly, except that a template-argument
10082 deduced from an array bound may be of any integral type.
10083 The non-type parameter might use already deduced type parameters. */
10084 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10085 if (!TREE_TYPE (arg))
10086 /* Template-parameter dependent expression. Just accept it for now.
10087 It will later be processed in convert_template_argument. */
10089 else if (same_type_p (TREE_TYPE (arg), tparm))
10091 else if ((strict & UNIFY_ALLOW_INTEGER)
10092 && (TREE_CODE (tparm) == INTEGER_TYPE
10093 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10094 /* Convert the ARG to the type of PARM; the deduced non-type
10095 template argument must exactly match the types of the
10096 corresponding parameter. */
10097 arg = fold (build_nop (TREE_TYPE (parm), arg));
10098 else if (uses_template_parms (tparm))
10099 /* We haven't deduced the type of this parameter yet. Try again
10105 TREE_VEC_ELT (targs, idx) = arg;
10110 /* A pointer-to-member constant can be unified only with
10111 another constant. */
10112 if (TREE_CODE (arg) != PTRMEM_CST)
10115 /* Just unify the class member. It would be useless (and possibly
10116 wrong, depending on the strict flags) to unify also
10117 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10118 arg refer to the same variable, even if through different
10119 classes. For instance:
10121 struct A { int x; };
10124 Unification of &A::x and &B::x must succeed. */
10125 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10126 PTRMEM_CST_MEMBER (arg), strict);
10131 if (TREE_CODE (arg) != POINTER_TYPE)
10134 /* [temp.deduct.call]
10136 A can be another pointer or pointer to member type that can
10137 be converted to the deduced A via a qualification
10138 conversion (_conv.qual_).
10140 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10141 This will allow for additional cv-qualification of the
10142 pointed-to types if appropriate. */
10144 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10145 /* The derived-to-base conversion only persists through one
10146 level of pointers. */
10147 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10149 return unify (tparms, targs, TREE_TYPE (parm),
10150 TREE_TYPE (arg), strict);
10153 case REFERENCE_TYPE:
10154 if (TREE_CODE (arg) != REFERENCE_TYPE)
10156 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10157 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10160 if (TREE_CODE (arg) != ARRAY_TYPE)
10162 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10163 != (TYPE_DOMAIN (arg) == NULL_TREE))
10165 if (TYPE_DOMAIN (parm) != NULL_TREE)
10170 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10171 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10173 /* Our representation of array types uses "N - 1" as the
10174 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10175 not an integer constant. */
10176 if (TREE_CODE (parm_max) == MINUS_EXPR)
10178 arg_max = fold_build2 (PLUS_EXPR,
10181 TREE_OPERAND (parm_max, 1));
10182 parm_max = TREE_OPERAND (parm_max, 0);
10185 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10188 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10189 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10196 case ENUMERAL_TYPE:
10198 if (TREE_CODE (arg) != TREE_CODE (parm))
10201 /* We have already checked cv-qualification at the top of the
10203 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10206 /* As far as unification is concerned, this wins. Later checks
10207 will invalidate it if necessary. */
10210 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10211 /* Type INTEGER_CST can come from ordinary constant template args. */
10213 while (TREE_CODE (arg) == NOP_EXPR)
10214 arg = TREE_OPERAND (arg, 0);
10216 if (TREE_CODE (arg) != INTEGER_CST)
10218 return !tree_int_cst_equal (parm, arg);
10223 if (TREE_CODE (arg) != TREE_VEC)
10225 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10227 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10228 if (unify (tparms, targs,
10229 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10237 if (TREE_CODE (arg) != TREE_CODE (parm))
10240 if (TYPE_PTRMEMFUNC_P (parm))
10242 if (!TYPE_PTRMEMFUNC_P (arg))
10245 return unify (tparms, targs,
10246 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10247 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10251 if (CLASSTYPE_TEMPLATE_INFO (parm))
10253 tree t = NULL_TREE;
10255 if (strict_in & UNIFY_ALLOW_DERIVED)
10257 /* First, we try to unify the PARM and ARG directly. */
10258 t = try_class_unification (tparms, targs,
10263 /* Fallback to the special case allowed in
10264 [temp.deduct.call]:
10266 If P is a class, and P has the form
10267 template-id, then A can be a derived class of
10268 the deduced A. Likewise, if P is a pointer to
10269 a class of the form template-id, A can be a
10270 pointer to a derived class pointed to by the
10272 t = get_template_base (tparms, targs, parm, arg);
10278 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10279 && (CLASSTYPE_TI_TEMPLATE (parm)
10280 == CLASSTYPE_TI_TEMPLATE (arg)))
10281 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10282 Then, we should unify `int' and `U'. */
10285 /* There's no chance of unification succeeding. */
10288 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10289 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10291 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10296 case FUNCTION_TYPE:
10297 if (TREE_CODE (arg) != TREE_CODE (parm))
10300 /* CV qualifications for methods can never be deduced, they must
10301 match exactly. We need to check them explicitly here,
10302 because type_unification_real treats them as any other
10303 cvqualified parameter. */
10304 if (TREE_CODE (parm) == METHOD_TYPE
10305 && (!check_cv_quals_for_unify
10307 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
10308 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
10311 if (unify (tparms, targs, TREE_TYPE (parm),
10312 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10314 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10315 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
10319 /* Unify a pointer to member with a pointer to member function, which
10320 deduces the type of the member as a function type. */
10321 if (TYPE_PTRMEMFUNC_P (arg))
10325 cp_cv_quals cv_quals;
10327 /* Check top-level cv qualifiers */
10328 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
10331 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10332 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
10335 /* Determine the type of the function we are unifying against. */
10336 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
10338 build_function_type (TREE_TYPE (method_type),
10339 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
10341 /* Extract the cv-qualifiers of the member function from the
10342 implicit object parameter and place them on the function
10343 type to be restored later. */
10345 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
10346 fntype = build_qualified_type (fntype, cv_quals);
10347 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
10350 if (TREE_CODE (arg) != OFFSET_TYPE)
10352 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10353 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10355 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10359 if (DECL_TEMPLATE_PARM_P (parm))
10360 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10361 if (arg != integral_constant_value (parm))
10366 case TEMPLATE_DECL:
10367 /* Matched cases are handled by the ARG == PARM test above. */
10371 gcc_assert (EXPR_P (parm));
10373 /* We must be looking at an expression. This can happen with
10377 void foo(S<I>, S<I + 2>);
10379 This is a "nondeduced context":
10383 The nondeduced contexts are:
10385 --A type that is a template-id in which one or more of
10386 the template-arguments is an expression that references
10387 a template-parameter.
10389 In these cases, we assume deduction succeeded, but don't
10390 actually infer any unifications. */
10392 if (!uses_template_parms (parm)
10393 && !template_args_equal (parm, arg))
10400 /* Note that DECL can be defined in this translation unit, if
10404 mark_definable (tree decl)
10407 DECL_NOT_REALLY_EXTERN (decl) = 1;
10408 FOR_EACH_CLONE (clone, decl)
10409 DECL_NOT_REALLY_EXTERN (clone) = 1;
10412 /* Called if RESULT is explicitly instantiated, or is a member of an
10413 explicitly instantiated class. */
10416 mark_decl_instantiated (tree result, int extern_p)
10418 SET_DECL_EXPLICIT_INSTANTIATION (result);
10420 /* If this entity has already been written out, it's too late to
10421 make any modifications. */
10422 if (TREE_ASM_WRITTEN (result))
10425 if (TREE_CODE (result) != FUNCTION_DECL)
10426 /* The TREE_PUBLIC flag for function declarations will have been
10427 set correctly by tsubst. */
10428 TREE_PUBLIC (result) = 1;
10430 /* This might have been set by an earlier implicit instantiation. */
10431 DECL_COMDAT (result) = 0;
10434 DECL_NOT_REALLY_EXTERN (result) = 0;
10437 mark_definable (result);
10438 /* Always make artificials weak. */
10439 if (DECL_ARTIFICIAL (result) && flag_weak)
10440 comdat_linkage (result);
10441 /* For WIN32 we also want to put explicit instantiations in
10442 linkonce sections. */
10443 else if (TREE_PUBLIC (result))
10444 maybe_make_one_only (result);
10447 /* If EXTERN_P, then this function will not be emitted -- unless
10448 followed by an explicit instantiation, at which point its linkage
10449 will be adjusted. If !EXTERN_P, then this function will be
10450 emitted here. In neither circumstance do we want
10451 import_export_decl to adjust the linkage. */
10452 DECL_INTERFACE_KNOWN (result) = 1;
10455 /* Given two function templates PAT1 and PAT2, return:
10457 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10458 -1 if PAT2 is more specialized than PAT1.
10459 0 if neither is more specialized.
10461 LEN indicates the number of parameters we should consider
10462 (defaulted parameters should not be considered).
10464 The 1998 std underspecified function template partial ordering, and
10465 DR214 addresses the issue. We take pairs of arguments, one from
10466 each of the templates, and deduce them against each other. One of
10467 the templates will be more specialized if all the *other*
10468 template's arguments deduce against its arguments and at least one
10469 of its arguments *does* *not* deduce against the other template's
10470 corresponding argument. Deduction is done as for class templates.
10471 The arguments used in deduction have reference and top level cv
10472 qualifiers removed. Iff both arguments were originally reference
10473 types *and* deduction succeeds in both directions, the template
10474 with the more cv-qualified argument wins for that pairing (if
10475 neither is more cv-qualified, they both are equal). Unlike regular
10476 deduction, after all the arguments have been deduced in this way,
10477 we do *not* verify the deduced template argument values can be
10478 substituted into non-deduced contexts, nor do we have to verify
10479 that all template arguments have been deduced. */
10482 more_specialized_fn (tree pat1, tree pat2, int len)
10484 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
10485 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
10486 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
10487 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
10488 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
10489 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
10490 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
10491 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
10495 /* Remove the this parameter from non-static member functions. If
10496 one is a non-static member function and the other is not a static
10497 member function, remove the first parameter from that function
10498 also. This situation occurs for operator functions where we
10499 locate both a member function (with this pointer) and non-member
10500 operator (with explicit first operand). */
10501 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
10503 len--; /* LEN is the number of significant arguments for DECL1 */
10504 args1 = TREE_CHAIN (args1);
10505 if (!DECL_STATIC_FUNCTION_P (decl2))
10506 args2 = TREE_CHAIN (args2);
10508 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
10510 args2 = TREE_CHAIN (args2);
10511 if (!DECL_STATIC_FUNCTION_P (decl1))
10514 args1 = TREE_CHAIN (args1);
10518 /* If only one is a conversion operator, they are unordered. */
10519 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
10522 /* Consider the return type for a conversion function */
10523 if (DECL_CONV_FN_P (decl1))
10525 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
10526 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
10530 processing_template_decl++;
10534 tree arg1 = TREE_VALUE (args1);
10535 tree arg2 = TREE_VALUE (args2);
10536 int deduce1, deduce2;
10540 if (TREE_CODE (arg1) == REFERENCE_TYPE)
10542 arg1 = TREE_TYPE (arg1);
10543 quals1 = cp_type_quals (arg1);
10546 if (TREE_CODE (arg2) == REFERENCE_TYPE)
10548 arg2 = TREE_TYPE (arg2);
10549 quals2 = cp_type_quals (arg2);
10552 if ((quals1 < 0) != (quals2 < 0))
10554 /* Only of the args is a reference, see if we should apply
10555 array/function pointer decay to it. This is not part of
10556 DR214, but is, IMHO, consistent with the deduction rules
10557 for the function call itself, and with our earlier
10558 implementation of the underspecified partial ordering
10559 rules. (nathan). */
10562 switch (TREE_CODE (arg1))
10565 arg1 = TREE_TYPE (arg1);
10567 case FUNCTION_TYPE:
10568 arg1 = build_pointer_type (arg1);
10577 switch (TREE_CODE (arg2))
10580 arg2 = TREE_TYPE (arg2);
10582 case FUNCTION_TYPE:
10583 arg2 = build_pointer_type (arg2);
10592 arg1 = TYPE_MAIN_VARIANT (arg1);
10593 arg2 = TYPE_MAIN_VARIANT (arg2);
10595 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
10596 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
10602 if (better1 < 0 && better2 < 0)
10603 /* We've failed to deduce something in either direction.
10604 These must be unordered. */
10607 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
10609 /* Deduces in both directions, see if quals can
10610 disambiguate. Pretend the worse one failed to deduce. */
10611 if ((quals1 & quals2) == quals2)
10613 if ((quals1 & quals2) == quals1)
10616 if (deduce1 && !deduce2 && !better2)
10618 if (deduce2 && !deduce1 && !better1)
10621 args1 = TREE_CHAIN (args1);
10622 args2 = TREE_CHAIN (args2);
10625 processing_template_decl--;
10627 return (better1 > 0) - (better2 > 0);
10630 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10632 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10633 -1 if PAT2 is more specialized than PAT1.
10634 0 if neither is more specialized.
10636 FULL_ARGS is the full set of template arguments that triggers this
10637 partial ordering. */
10640 more_specialized_class (tree pat1, tree pat2, tree full_args)
10645 /* Just like what happens for functions, if we are ordering between
10646 different class template specializations, we may encounter dependent
10647 types in the arguments, and we need our dependency check functions
10648 to behave correctly. */
10649 ++processing_template_decl;
10650 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10651 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10655 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10656 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10659 --processing_template_decl;
10664 /* Return the template arguments that will produce the function signature
10665 DECL from the function template FN, with the explicit template
10666 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
10667 also match. Return NULL_TREE if no satisfactory arguments could be
10671 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
10673 int ntparms = DECL_NTPARMS (fn);
10674 tree targs = make_tree_vec (ntparms);
10676 tree decl_arg_types;
10678 /* Substitute the explicit template arguments into the type of DECL.
10679 The call to fn_type_unification will handle substitution into the
10681 decl_type = TREE_TYPE (decl);
10682 if (explicit_args && uses_template_parms (decl_type))
10685 tree converted_args;
10687 if (DECL_TEMPLATE_INFO (decl))
10688 tmpl = DECL_TI_TEMPLATE (decl);
10690 /* We can get here for some invalid specializations. */
10694 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10695 explicit_args, NULL_TREE,
10696 tf_none, /*require_all_arguments=*/0));
10697 if (converted_args == error_mark_node)
10700 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10701 if (decl_type == error_mark_node)
10705 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10706 /* Never do unification on the 'this' parameter. */
10707 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10708 decl_arg_types = TREE_CHAIN (decl_arg_types);
10710 if (fn_type_unification (fn, explicit_args, targs,
10712 (check_rettype || DECL_CONV_FN_P (fn)
10713 ? TREE_TYPE (decl_type) : NULL_TREE),
10714 DEDUCE_EXACT, LOOKUP_NORMAL))
10720 /* Return the innermost template arguments that, when applied to a
10721 template specialization whose innermost template parameters are
10722 TPARMS, and whose specialization arguments are PARMS, yield the
10725 For example, suppose we have:
10727 template <class T, class U> struct S {};
10728 template <class T> struct S<T*, int> {};
10730 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10731 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10732 int}. The resulting vector will be {double}, indicating that `T'
10733 is bound to `double'. */
10736 get_class_bindings (tree tparms, tree parms, tree args)
10738 int i, ntparms = TREE_VEC_LENGTH (tparms);
10739 tree vec = make_tree_vec (ntparms);
10741 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10745 for (i = 0; i < ntparms; ++i)
10746 if (! TREE_VEC_ELT (vec, i))
10749 if (verify_class_unification (vec, parms, args))
10755 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10756 Pick the most specialized template, and return the corresponding
10757 instantiation, or if there is no corresponding instantiation, the
10758 template itself. If there is no most specialized template,
10759 error_mark_node is returned. If there are no templates at all,
10760 NULL_TREE is returned. */
10763 most_specialized_instantiation (tree instantiations)
10767 if (!instantiations)
10770 ++processing_template_decl;
10772 champ = instantiations;
10773 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10777 if (get_bindings (TREE_VALUE (champ),
10778 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10779 NULL_TREE, /*check_ret=*/false))
10782 if (get_bindings (TREE_VALUE (fn),
10783 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10784 NULL_TREE, /*check_ret=*/false))
10790 /* Equally specialized, move to next function. If there
10791 is no next function, nothing's most specialized. */
10792 fn = TREE_CHAIN (fn);
10798 /* Now verify that champ is better than everything earlier in the
10799 instantiation list. */
10800 for (fn = instantiations; fn != champ; fn = TREE_CHAIN (fn))
10801 if (get_bindings (TREE_VALUE (champ),
10802 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10803 NULL_TREE, /*check_ret=*/false)
10804 || !get_bindings (TREE_VALUE (fn),
10805 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10806 NULL_TREE, /*check_ret=*/false))
10812 processing_template_decl--;
10815 return error_mark_node;
10817 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10820 /* Return the most specialized of the list of templates in FNS that can
10821 produce an instantiation matching DECL, given the explicit template
10822 arguments EXPLICIT_ARGS. */
10825 most_specialized (tree fns, tree decl, tree explicit_args)
10827 tree candidates = NULL_TREE;
10830 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10832 tree candidate = TREE_VALUE (fn);
10834 args = get_bindings (candidate, decl, explicit_args, /*check_ret=*/true);
10836 candidates = tree_cons (NULL_TREE, candidate, candidates);
10839 return most_specialized_instantiation (candidates);
10842 /* If DECL is a specialization of some template, return the most
10843 general such template. Otherwise, returns NULL_TREE.
10845 For example, given:
10847 template <class T> struct S { template <class U> void f(U); };
10849 if TMPL is `template <class U> void S<int>::f(U)' this will return
10850 the full template. This function will not trace past partial
10851 specializations, however. For example, given in addition:
10853 template <class T> struct S<T*> { template <class U> void f(U); };
10855 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10856 `template <class T> template <class U> S<T*>::f(U)'. */
10859 most_general_template (tree decl)
10861 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10862 an immediate specialization. */
10863 if (TREE_CODE (decl) == FUNCTION_DECL)
10865 if (DECL_TEMPLATE_INFO (decl)) {
10866 decl = DECL_TI_TEMPLATE (decl);
10868 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10869 template friend. */
10870 if (TREE_CODE (decl) != TEMPLATE_DECL)
10876 /* Look for more and more general templates. */
10877 while (DECL_TEMPLATE_INFO (decl))
10879 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10880 (See cp-tree.h for details.) */
10881 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10884 if (CLASS_TYPE_P (TREE_TYPE (decl))
10885 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10888 /* Stop if we run into an explicitly specialized class template. */
10889 if (!DECL_NAMESPACE_SCOPE_P (decl)
10890 && DECL_CONTEXT (decl)
10891 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10894 decl = DECL_TI_TEMPLATE (decl);
10900 /* Return the most specialized of the class template specializations
10901 of TMPL which can produce an instantiation matching ARGS, or
10902 error_mark_node if the choice is ambiguous. */
10905 most_specialized_class (tree tmpl, tree args)
10907 tree list = NULL_TREE;
10912 tmpl = most_general_template (tmpl);
10913 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10916 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10919 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10920 TREE_TYPE (list) = TREE_TYPE (t);
10929 t = TREE_CHAIN (t);
10930 for (; t; t = TREE_CHAIN (t))
10932 fate = more_specialized_class (champ, t, args);
10939 t = TREE_CHAIN (t);
10941 return error_mark_node;
10947 for (t = list; t && t != champ; t = TREE_CHAIN (t))
10949 fate = more_specialized_class (champ, t, args);
10951 return error_mark_node;
10957 /* Explicitly instantiate DECL. */
10960 do_decl_instantiation (tree decl, tree storage)
10962 tree result = NULL_TREE;
10966 /* An error occurred, for which grokdeclarator has already issued
10967 an appropriate message. */
10969 else if (! DECL_LANG_SPECIFIC (decl))
10971 error ("explicit instantiation of non-template %q#D", decl);
10974 else if (TREE_CODE (decl) == VAR_DECL)
10976 /* There is an asymmetry here in the way VAR_DECLs and
10977 FUNCTION_DECLs are handled by grokdeclarator. In the case of
10978 the latter, the DECL we get back will be marked as a
10979 template instantiation, and the appropriate
10980 DECL_TEMPLATE_INFO will be set up. This does not happen for
10981 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
10982 should handle VAR_DECLs as it currently handles
10984 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
10985 if (!result || TREE_CODE (result) != VAR_DECL)
10987 error ("no matching template for %qD found", decl);
10991 else if (TREE_CODE (decl) != FUNCTION_DECL)
10993 error ("explicit instantiation of %q#D", decl);
10999 /* Check for various error cases. Note that if the explicit
11000 instantiation is valid the RESULT will currently be marked as an
11001 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
11002 until we get here. */
11004 if (DECL_TEMPLATE_SPECIALIZATION (result))
11006 /* DR 259 [temp.spec].
11008 Both an explicit instantiation and a declaration of an explicit
11009 specialization shall not appear in a program unless the explicit
11010 instantiation follows a declaration of the explicit specialization.
11012 For a given set of template parameters, if an explicit
11013 instantiation of a template appears after a declaration of an
11014 explicit specialization for that template, the explicit
11015 instantiation has no effect. */
11018 else if (DECL_EXPLICIT_INSTANTIATION (result))
11022 No program shall explicitly instantiate any template more
11025 We check DECL_NOT_REALLY_EXTERN so as not to complain when
11026 the first instantiation was `extern' and the second is not,
11027 and EXTERN_P for the opposite case. */
11028 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
11029 pedwarn ("duplicate explicit instantiation of %q#D", result);
11030 /* If an "extern" explicit instantiation follows an ordinary
11031 explicit instantiation, the template is instantiated. */
11035 else if (!DECL_IMPLICIT_INSTANTIATION (result))
11037 error ("no matching template for %qD found", result);
11040 else if (!DECL_TEMPLATE_INFO (result))
11042 pedwarn ("explicit instantiation of non-template %q#D", result);
11046 if (storage == NULL_TREE)
11048 else if (storage == ridpointers[(int) RID_EXTERN])
11050 if (pedantic && !in_system_header)
11051 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
11056 error ("storage class %qD applied to template instantiation", storage);
11058 check_explicit_instantiation_namespace (result);
11059 mark_decl_instantiated (result, extern_p);
11061 instantiate_decl (result, /*defer_ok=*/1,
11062 /*expl_inst_class_mem_p=*/false);
11066 mark_class_instantiated (tree t, int extern_p)
11068 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
11069 SET_CLASSTYPE_INTERFACE_KNOWN (t);
11070 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
11071 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
11074 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
11075 rest_of_type_compilation (t, 1);
11079 /* Called from do_type_instantiation through binding_table_foreach to
11080 do recursive instantiation for the type bound in ENTRY. */
11082 bt_instantiate_type_proc (binding_entry entry, void *data)
11084 tree storage = *(tree *) data;
11086 if (IS_AGGR_TYPE (entry->type)
11087 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
11088 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
11091 /* Called from do_type_instantiation to instantiate a member
11092 (a member function or a static member variable) of an
11093 explicitly instantiated class template. */
11095 instantiate_class_member (tree decl, int extern_p)
11097 mark_decl_instantiated (decl, extern_p);
11099 instantiate_decl (decl, /*defer_ok=*/1,
11100 /*expl_inst_class_mem_p=*/true);
11103 /* Perform an explicit instantiation of template class T. STORAGE, if
11104 non-null, is the RID for extern, inline or static. COMPLAIN is
11105 nonzero if this is called from the parser, zero if called recursively,
11106 since the standard is unclear (as detailed below). */
11109 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
11114 int previous_instantiation_extern_p = 0;
11116 if (TREE_CODE (t) == TYPE_DECL)
11119 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
11121 error ("explicit instantiation of non-template type %qT", t);
11127 if (!COMPLETE_TYPE_P (t))
11129 if (complain & tf_error)
11130 error ("explicit instantiation of %q#T before definition of template",
11135 if (storage != NULL_TREE)
11137 if (pedantic && !in_system_header)
11138 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
11141 if (storage == ridpointers[(int) RID_INLINE])
11143 else if (storage == ridpointers[(int) RID_EXTERN])
11145 else if (storage == ridpointers[(int) RID_STATIC])
11149 error ("storage class %qD applied to template instantiation",
11155 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
11157 /* DR 259 [temp.spec].
11159 Both an explicit instantiation and a declaration of an explicit
11160 specialization shall not appear in a program unless the explicit
11161 instantiation follows a declaration of the explicit specialization.
11163 For a given set of template parameters, if an explicit
11164 instantiation of a template appears after a declaration of an
11165 explicit specialization for that template, the explicit
11166 instantiation has no effect. */
11169 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
11173 No program shall explicitly instantiate any template more
11176 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
11177 instantiation was `extern'. If EXTERN_P then the second is.
11178 These cases are OK. */
11179 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11181 if (!previous_instantiation_extern_p && !extern_p
11182 && (complain & tf_error))
11183 pedwarn ("duplicate explicit instantiation of %q#T", t);
11185 /* If we've already instantiated the template, just return now. */
11186 if (!CLASSTYPE_INTERFACE_ONLY (t))
11190 check_explicit_instantiation_namespace (TYPE_NAME (t));
11191 mark_class_instantiated (t, extern_p);
11199 /* In contrast to implicit instantiation, where only the
11200 declarations, and not the definitions, of members are
11201 instantiated, we have here:
11205 The explicit instantiation of a class template specialization
11206 implies the instantiation of all of its members not
11207 previously explicitly specialized in the translation unit
11208 containing the explicit instantiation.
11210 Of course, we can't instantiate member template classes, since
11211 we don't have any arguments for them. Note that the standard
11212 is unclear on whether the instantiation of the members are
11213 *explicit* instantiations or not. However, the most natural
11214 interpretation is that it should be an explicit instantiation. */
11217 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11218 if (TREE_CODE (tmp) == FUNCTION_DECL
11219 && DECL_TEMPLATE_INSTANTIATION (tmp))
11220 instantiate_class_member (tmp, extern_p);
11222 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11223 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11224 instantiate_class_member (tmp, extern_p);
11226 if (CLASSTYPE_NESTED_UTDS (t))
11227 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11228 bt_instantiate_type_proc, &storage);
11232 /* Given a function DECL, which is a specialization of TMPL, modify
11233 DECL to be a re-instantiation of TMPL with the same template
11234 arguments. TMPL should be the template into which tsubst'ing
11235 should occur for DECL, not the most general template.
11237 One reason for doing this is a scenario like this:
11240 void f(const T&, int i);
11242 void g() { f(3, 7); }
11245 void f(const T& t, const int i) { }
11247 Note that when the template is first instantiated, with
11248 instantiate_template, the resulting DECL will have no name for the
11249 first parameter, and the wrong type for the second. So, when we go
11250 to instantiate the DECL, we regenerate it. */
11253 regenerate_decl_from_template (tree decl, tree tmpl)
11255 /* The arguments used to instantiate DECL, from the most general
11260 args = DECL_TI_ARGS (decl);
11261 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11263 /* Make sure that we can see identifiers, and compute access
11265 push_access_scope (decl);
11267 if (TREE_CODE (decl) == FUNCTION_DECL)
11275 args_depth = TMPL_ARGS_DEPTH (args);
11276 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11277 if (args_depth > parms_depth)
11278 args = get_innermost_template_args (args, parms_depth);
11280 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11281 args, tf_error, NULL_TREE);
11283 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11286 /* Merge parameter declarations. */
11287 decl_parm = skip_artificial_parms_for (decl,
11288 DECL_ARGUMENTS (decl));
11290 = skip_artificial_parms_for (code_pattern,
11291 DECL_ARGUMENTS (code_pattern));
11297 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11298 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11299 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11301 parm_type = type_decays_to (parm_type);
11302 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11303 TREE_TYPE (decl_parm) = parm_type;
11304 attributes = DECL_ATTRIBUTES (pattern_parm);
11305 if (DECL_ATTRIBUTES (decl_parm) != attributes)
11307 DECL_ATTRIBUTES (decl_parm) = attributes;
11308 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
11310 decl_parm = TREE_CHAIN (decl_parm);
11311 pattern_parm = TREE_CHAIN (pattern_parm);
11314 /* Merge additional specifiers from the CODE_PATTERN. */
11315 if (DECL_DECLARED_INLINE_P (code_pattern)
11316 && !DECL_DECLARED_INLINE_P (decl))
11317 DECL_DECLARED_INLINE_P (decl) = 1;
11318 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11319 DECL_INLINE (decl) = 1;
11321 else if (TREE_CODE (decl) == VAR_DECL)
11322 DECL_INITIAL (decl) =
11323 tsubst_expr (DECL_INITIAL (code_pattern), args,
11324 tf_error, DECL_TI_TEMPLATE (decl));
11326 gcc_unreachable ();
11328 pop_access_scope (decl);
11331 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11332 substituted to get DECL. */
11335 template_for_substitution (tree decl)
11337 tree tmpl = DECL_TI_TEMPLATE (decl);
11339 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11340 for the instantiation. This is not always the most general
11341 template. Consider, for example:
11344 struct S { template <class U> void f();
11345 template <> void f<int>(); };
11347 and an instantiation of S<double>::f<int>. We want TD to be the
11348 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11349 while (/* An instantiation cannot have a definition, so we need a
11350 more general template. */
11351 DECL_TEMPLATE_INSTANTIATION (tmpl)
11352 /* We must also deal with friend templates. Given:
11354 template <class T> struct S {
11355 template <class U> friend void f() {};
11358 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11359 so far as the language is concerned, but that's still
11360 where we get the pattern for the instantiation from. On
11361 other hand, if the definition comes outside the class, say:
11363 template <class T> struct S {
11364 template <class U> friend void f();
11366 template <class U> friend void f() {}
11368 we don't need to look any further. That's what the check for
11369 DECL_INITIAL is for. */
11370 || (TREE_CODE (decl) == FUNCTION_DECL
11371 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11372 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11374 /* The present template, TD, should not be a definition. If it
11375 were a definition, we should be using it! Note that we
11376 cannot restructure the loop to just keep going until we find
11377 a template with a definition, since that might go too far if
11378 a specialization was declared, but not defined. */
11379 gcc_assert (TREE_CODE (decl) != VAR_DECL
11380 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11382 /* Fetch the more general template. */
11383 tmpl = DECL_TI_TEMPLATE (tmpl);
11389 /* Produce the definition of D, a _DECL generated from a template. If
11390 DEFER_OK is nonzero, then we don't have to actually do the
11391 instantiation now; we just have to do it sometime. Normally it is
11392 an error if this is an explicit instantiation but D is undefined.
11393 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
11394 explicitly instantiated class template. */
11397 instantiate_decl (tree d, int defer_ok,
11398 bool expl_inst_class_mem_p)
11400 tree tmpl = DECL_TI_TEMPLATE (d);
11407 bool pattern_defined;
11409 location_t saved_loc = input_location;
11412 /* This function should only be used to instantiate templates for
11413 functions and static member variables. */
11414 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11415 || TREE_CODE (d) == VAR_DECL);
11417 /* Variables are never deferred; if instantiation is required, they
11418 are instantiated right away. That allows for better code in the
11419 case that an expression refers to the value of the variable --
11420 if the variable has a constant value the referring expression can
11421 take advantage of that fact. */
11422 if (TREE_CODE (d) == VAR_DECL)
11425 /* Don't instantiate cloned functions. Instead, instantiate the
11426 functions they cloned. */
11427 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11428 d = DECL_CLONED_FUNCTION (d);
11430 if (DECL_TEMPLATE_INSTANTIATED (d))
11431 /* D has already been instantiated. It might seem reasonable to
11432 check whether or not D is an explicit instantiation, and, if so,
11433 stop here. But when an explicit instantiation is deferred
11434 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11435 is set, even though we still need to do the instantiation. */
11438 /* If we already have a specialization of this declaration, then
11439 there's no reason to instantiate it. Note that
11440 retrieve_specialization gives us both instantiations and
11441 specializations, so we must explicitly check
11442 DECL_TEMPLATE_SPECIALIZATION. */
11443 gen_tmpl = most_general_template (tmpl);
11444 gen_args = DECL_TI_ARGS (d);
11445 spec = retrieve_specialization (gen_tmpl, gen_args,
11446 /*class_specializations_p=*/false);
11447 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11450 /* This needs to happen before any tsubsting. */
11451 if (! push_tinst_level (d))
11454 timevar_push (TV_PARSE);
11456 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11457 for the instantiation. */
11458 td = template_for_substitution (d);
11459 code_pattern = DECL_TEMPLATE_RESULT (td);
11461 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11462 || DECL_TEMPLATE_SPECIALIZATION (td))
11463 /* In the case of a friend template whose definition is provided
11464 outside the class, we may have too many arguments. Drop the
11465 ones we don't need. The same is true for specializations. */
11466 args = get_innermost_template_args
11467 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11471 if (TREE_CODE (d) == FUNCTION_DECL)
11472 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11474 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11476 /* We may be in the middle of deferred access check. Disable it now. */
11477 push_deferring_access_checks (dk_no_deferred);
11479 /* Unless an explicit instantiation directive has already determined
11480 the linkage of D, remember that a definition is available for
11482 if (pattern_defined
11483 && !DECL_INTERFACE_KNOWN (d)
11484 && !DECL_NOT_REALLY_EXTERN (d))
11485 mark_definable (d);
11487 input_location = DECL_SOURCE_LOCATION (d);
11489 /* If D is a member of an explicitly instantiated class template,
11490 and no definition is available, treat it like an implicit
11492 if (!pattern_defined && expl_inst_class_mem_p
11493 && DECL_EXPLICIT_INSTANTIATION (d))
11495 DECL_NOT_REALLY_EXTERN (d) = 0;
11496 DECL_INTERFACE_KNOWN (d) = 0;
11497 SET_DECL_IMPLICIT_INSTANTIATION (d);
11502 /* Recheck the substitutions to obtain any warning messages
11503 about ignoring cv qualifiers. */
11504 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11505 tree type = TREE_TYPE (gen);
11507 /* Make sure that we can see identifiers, and compute access
11508 correctly. D is already the target FUNCTION_DECL with the
11510 push_access_scope (d);
11512 if (TREE_CODE (gen) == FUNCTION_DECL)
11514 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11515 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11516 tf_error | tf_warning, d);
11517 /* Don't simply tsubst the function type, as that will give
11518 duplicate warnings about poor parameter qualifications.
11519 The function arguments are the same as the decl_arguments
11520 without the top level cv qualifiers. */
11521 type = TREE_TYPE (type);
11523 tsubst (type, gen_args, tf_error | tf_warning, d);
11525 pop_access_scope (d);
11528 /* Check to see whether we know that this template will be
11529 instantiated in some other file, as with "extern template"
11531 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
11532 /* In general, we do not instantiate such templates... */
11534 /* ... but we instantiate inline functions so that we can inline
11536 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
11537 /* ... we instantiate static data members whose values are
11538 needed in integral constant expressions. */
11539 && ! (TREE_CODE (d) == VAR_DECL
11540 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
11542 /* Defer all other templates, unless we have been explicitly
11543 forbidden from doing so. */
11544 if (/* If there is no definition, we cannot instantiate the
11547 /* If it's OK to postpone instantiation, do so. */
11549 /* If this is a static data member that will be defined
11550 elsewhere, we don't want to instantiate the entire data
11551 member, but we do want to instantiate the initializer so that
11552 we can substitute that elsewhere. */
11553 || (external_p && TREE_CODE (d) == VAR_DECL))
11555 /* The definition of the static data member is now required so
11556 we must substitute the initializer. */
11557 if (TREE_CODE (d) == VAR_DECL
11558 && !DECL_INITIAL (d)
11559 && DECL_INITIAL (code_pattern))
11564 ns = decl_namespace_context (d);
11565 push_nested_namespace (ns);
11566 push_nested_class (DECL_CONTEXT (d));
11567 init = tsubst_expr (DECL_INITIAL (code_pattern),
11569 tf_error | tf_warning, NULL_TREE);
11570 DECL_INITIAL (d) = NULL_TREE;
11571 finish_static_data_member_decl (d, init,
11572 /*asmspec_tree=*/NULL_TREE,
11573 LOOKUP_ONLYCONVERTING);
11574 pop_nested_class ();
11575 pop_nested_namespace (ns);
11578 /* We restore the source position here because it's used by
11579 add_pending_template. */
11580 input_location = saved_loc;
11582 if (at_eof && !pattern_defined
11583 && DECL_EXPLICIT_INSTANTIATION (d))
11586 The definition of a non-exported function template, a
11587 non-exported member function template, or a non-exported
11588 member function or static data member of a class template
11589 shall be present in every translation unit in which it is
11590 explicitly instantiated. */
11592 ("explicit instantiation of %qD but no definition available", d);
11594 /* ??? Historically, we have instantiated inline functions, even
11595 when marked as "extern template". */
11596 if (!(external_p && TREE_CODE (d) == VAR_DECL))
11597 add_pending_template (d);
11600 /* Tell the repository that D is available in this translation unit
11601 -- and see if it is supposed to be instantiated here. */
11602 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11604 /* In a PCH file, despite the fact that the repository hasn't
11605 requested instantiation in the PCH it is still possible that
11606 an instantiation will be required in a file that includes the
11609 add_pending_template (d);
11610 /* Instantiate inline functions so that the inliner can do its
11611 job, even though we'll not be emitting a copy of this
11613 if (!(TREE_CODE (d) == FUNCTION_DECL
11614 && flag_inline_trees
11615 && DECL_DECLARED_INLINE_P (d)))
11619 need_push = !cfun || !global_bindings_p ();
11621 push_to_top_level ();
11623 /* Mark D as instantiated so that recursive calls to
11624 instantiate_decl do not try to instantiate it again. */
11625 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11627 /* Regenerate the declaration in case the template has been modified
11628 by a subsequent redeclaration. */
11629 regenerate_decl_from_template (d, td);
11631 /* We already set the file and line above. Reset them now in case
11632 they changed as a result of calling regenerate_decl_from_template. */
11633 input_location = DECL_SOURCE_LOCATION (d);
11635 if (TREE_CODE (d) == VAR_DECL)
11637 /* Clear out DECL_RTL; whatever was there before may not be right
11638 since we've reset the type of the declaration. */
11639 SET_DECL_RTL (d, NULL_RTX);
11640 DECL_IN_AGGR_P (d) = 0;
11642 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11643 initializer. That function will defer actual emission until
11644 we have a chance to determine linkage. */
11645 DECL_EXTERNAL (d) = 0;
11647 /* Enter the scope of D so that access-checking works correctly. */
11648 push_nested_class (DECL_CONTEXT (d));
11649 cp_finish_decl (d, DECL_INITIAL (d), NULL_TREE, 0);
11650 pop_nested_class ();
11652 else if (TREE_CODE (d) == FUNCTION_DECL)
11654 htab_t saved_local_specializations;
11659 /* Save away the current list, in case we are instantiating one
11660 template from within the body of another. */
11661 saved_local_specializations = local_specializations;
11663 /* Set up the list of local specializations. */
11664 local_specializations = htab_create (37,
11665 hash_local_specialization,
11666 eq_local_specializations,
11669 /* Set up context. */
11670 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11672 /* Create substitution entries for the parameters. */
11673 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11674 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11675 spec_parm = DECL_ARGUMENTS (d);
11676 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11678 register_local_specialization (spec_parm, tmpl_parm);
11679 spec_parm = skip_artificial_parms_for (d, spec_parm);
11680 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11684 register_local_specialization (spec_parm, tmpl_parm);
11685 tmpl_parm = TREE_CHAIN (tmpl_parm);
11686 spec_parm = TREE_CHAIN (spec_parm);
11688 gcc_assert (!spec_parm);
11690 /* Substitute into the body of the function. */
11691 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11692 tf_error | tf_warning, tmpl);
11694 /* We don't need the local specializations any more. */
11695 htab_delete (local_specializations);
11696 local_specializations = saved_local_specializations;
11698 /* Finish the function. */
11699 d = finish_function (0);
11700 expand_or_defer_fn (d);
11703 /* We're not deferring instantiation any more. */
11704 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11707 pop_from_top_level ();
11710 input_location = saved_loc;
11711 pop_deferring_access_checks ();
11712 pop_tinst_level ();
11714 timevar_pop (TV_PARSE);
11719 /* Run through the list of templates that we wish we could
11720 instantiate, and instantiate any we can. RETRIES is the
11721 number of times we retry pending template instantiation. */
11724 instantiate_pending_templates (int retries)
11727 tree last = NULL_TREE;
11729 location_t saved_loc = input_location;
11730 int saved_in_system_header = in_system_header;
11732 /* Instantiating templates may trigger vtable generation. This in turn
11733 may require further template instantiations. We place a limit here
11734 to avoid infinite loop. */
11735 if (pending_templates && retries >= max_tinst_depth)
11737 error ("template instantiation depth exceeds maximum of %d"
11738 " instantiating %q+D, possibly from virtual table generation"
11739 " (use -ftemplate-depth-NN to increase the maximum)",
11740 max_tinst_depth, TREE_VALUE (pending_templates));
11748 t = &pending_templates;
11751 tree instantiation = TREE_VALUE (*t);
11753 reopen_tinst_level (TREE_PURPOSE (*t));
11755 if (TYPE_P (instantiation))
11759 if (!COMPLETE_TYPE_P (instantiation))
11761 instantiate_class_template (instantiation);
11762 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11763 for (fn = TYPE_METHODS (instantiation);
11765 fn = TREE_CHAIN (fn))
11766 if (! DECL_ARTIFICIAL (fn))
11767 instantiate_decl (fn,
11769 /*expl_inst_class_mem_p=*/false);
11770 if (COMPLETE_TYPE_P (instantiation))
11774 if (COMPLETE_TYPE_P (instantiation))
11775 /* If INSTANTIATION has been instantiated, then we don't
11776 need to consider it again in the future. */
11777 *t = TREE_CHAIN (*t);
11781 t = &TREE_CHAIN (*t);
11786 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11787 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11790 = instantiate_decl (instantiation,
11792 /*expl_inst_class_mem_p=*/false);
11793 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11797 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11798 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11799 /* If INSTANTIATION has been instantiated, then we don't
11800 need to consider it again in the future. */
11801 *t = TREE_CHAIN (*t);
11805 t = &TREE_CHAIN (*t);
11809 current_tinst_level = NULL_TREE;
11811 last_pending_template = last;
11813 while (reconsider);
11815 input_location = saved_loc;
11816 in_system_header = saved_in_system_header;
11819 /* Substitute ARGVEC into T, which is a list of initializers for
11820 either base class or a non-static data member. The TREE_PURPOSEs
11821 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11822 instantiate_decl. */
11825 tsubst_initializer_list (tree t, tree argvec)
11827 tree inits = NULL_TREE;
11829 for (; t; t = TREE_CHAIN (t))
11834 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11836 decl = expand_member_init (decl);
11837 if (decl && !DECL_P (decl))
11838 in_base_initializer = 1;
11840 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11842 in_base_initializer = 0;
11846 init = build_tree_list (decl, init);
11847 TREE_CHAIN (init) = inits;
11854 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11857 set_current_access_from_decl (tree decl)
11859 if (TREE_PRIVATE (decl))
11860 current_access_specifier = access_private_node;
11861 else if (TREE_PROTECTED (decl))
11862 current_access_specifier = access_protected_node;
11864 current_access_specifier = access_public_node;
11867 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11868 is the instantiation (which should have been created with
11869 start_enum) and ARGS are the template arguments to use. */
11872 tsubst_enum (tree tag, tree newtag, tree args)
11876 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11881 decl = TREE_VALUE (e);
11882 /* Note that in a template enum, the TREE_VALUE is the
11883 CONST_DECL, not the corresponding INTEGER_CST. */
11884 value = tsubst_expr (DECL_INITIAL (decl),
11885 args, tf_error | tf_warning,
11888 /* Give this enumeration constant the correct access. */
11889 set_current_access_from_decl (decl);
11891 /* Actually build the enumerator itself. */
11892 build_enumerator (DECL_NAME (decl), value, newtag);
11895 finish_enum (newtag);
11896 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11897 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11900 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11901 its type -- but without substituting the innermost set of template
11902 arguments. So, innermost set of template parameters will appear in
11906 get_mostly_instantiated_function_type (tree decl)
11914 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11915 targs = DECL_TI_ARGS (decl);
11916 tparms = DECL_TEMPLATE_PARMS (tmpl);
11917 parm_depth = TMPL_PARMS_DEPTH (tparms);
11919 /* There should be as many levels of arguments as there are levels
11921 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11923 fn_type = TREE_TYPE (tmpl);
11925 if (parm_depth == 1)
11926 /* No substitution is necessary. */
11930 int i, save_access_control;
11933 /* Replace the innermost level of the TARGS with NULL_TREEs to
11934 let tsubst know not to substitute for those parameters. */
11935 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11936 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11937 SET_TMPL_ARGS_LEVEL (partial_args, i,
11938 TMPL_ARGS_LEVEL (targs, i));
11939 SET_TMPL_ARGS_LEVEL (partial_args,
11940 TMPL_ARGS_DEPTH (targs),
11941 make_tree_vec (DECL_NTPARMS (tmpl)));
11943 /* Disable access control as this function is used only during
11945 save_access_control = flag_access_control;
11946 flag_access_control = 0;
11948 ++processing_template_decl;
11949 /* Now, do the (partial) substitution to figure out the
11950 appropriate function type. */
11951 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
11952 --processing_template_decl;
11954 /* Substitute into the template parameters to obtain the real
11955 innermost set of parameters. This step is important if the
11956 innermost set of template parameters contains value
11957 parameters whose types depend on outer template parameters. */
11958 TREE_VEC_LENGTH (partial_args)--;
11959 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
11961 flag_access_control = save_access_control;
11967 /* Return truthvalue if we're processing a template different from
11968 the last one involved in diagnostics. */
11970 problematic_instantiation_changed (void)
11972 return last_template_error_tick != tinst_level_tick;
11975 /* Remember current template involved in diagnostics. */
11977 record_last_problematic_instantiation (void)
11979 last_template_error_tick = tinst_level_tick;
11983 current_instantiation (void)
11985 return current_tinst_level;
11988 /* [temp.param] Check that template non-type parm TYPE is of an allowable
11989 type. Return zero for ok, nonzero for disallowed. Issue error and
11990 warning messages under control of COMPLAIN. */
11993 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
11995 if (INTEGRAL_TYPE_P (type))
11997 else if (POINTER_TYPE_P (type))
11999 else if (TYPE_PTR_TO_MEMBER_P (type))
12001 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
12003 else if (TREE_CODE (type) == TYPENAME_TYPE)
12006 if (complain & tf_error)
12007 error ("%q#T is not a valid type for a template constant parameter", type);
12011 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
12012 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
12015 dependent_type_p_r (tree type)
12021 A type is dependent if it is:
12023 -- a template parameter. Template template parameters are types
12024 for us (since TYPE_P holds true for them) so we handle
12026 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
12027 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
12029 /* -- a qualified-id with a nested-name-specifier which contains a
12030 class-name that names a dependent type or whose unqualified-id
12031 names a dependent type. */
12032 if (TREE_CODE (type) == TYPENAME_TYPE)
12034 /* -- a cv-qualified type where the cv-unqualified type is
12036 type = TYPE_MAIN_VARIANT (type);
12037 /* -- a compound type constructed from any dependent type. */
12038 if (TYPE_PTR_TO_MEMBER_P (type))
12039 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
12040 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
12042 else if (TREE_CODE (type) == POINTER_TYPE
12043 || TREE_CODE (type) == REFERENCE_TYPE)
12044 return dependent_type_p (TREE_TYPE (type));
12045 else if (TREE_CODE (type) == FUNCTION_TYPE
12046 || TREE_CODE (type) == METHOD_TYPE)
12050 if (dependent_type_p (TREE_TYPE (type)))
12052 for (arg_type = TYPE_ARG_TYPES (type);
12054 arg_type = TREE_CHAIN (arg_type))
12055 if (dependent_type_p (TREE_VALUE (arg_type)))
12059 /* -- an array type constructed from any dependent type or whose
12060 size is specified by a constant expression that is
12061 value-dependent. */
12062 if (TREE_CODE (type) == ARRAY_TYPE)
12064 if (TYPE_DOMAIN (type)
12065 && ((value_dependent_expression_p
12066 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
12067 || (type_dependent_expression_p
12068 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
12070 return dependent_type_p (TREE_TYPE (type));
12073 /* -- a template-id in which either the template name is a template
12075 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
12077 /* ... or any of the template arguments is a dependent type or
12078 an expression that is type-dependent or value-dependent. */
12079 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
12080 && (any_dependent_template_arguments_p
12081 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
12084 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
12085 expression is not type-dependent, then it should already been
12087 if (TREE_CODE (type) == TYPEOF_TYPE)
12090 /* The standard does not specifically mention types that are local
12091 to template functions or local classes, but they should be
12092 considered dependent too. For example:
12094 template <int I> void f() {
12099 The size of `E' cannot be known until the value of `I' has been
12100 determined. Therefore, `E' must be considered dependent. */
12101 scope = TYPE_CONTEXT (type);
12102 if (scope && TYPE_P (scope))
12103 return dependent_type_p (scope);
12104 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
12105 return type_dependent_expression_p (scope);
12107 /* Other types are non-dependent. */
12111 /* Returns TRUE if TYPE is dependent, in the sense of
12112 [temp.dep.type]. */
12115 dependent_type_p (tree type)
12117 /* If there are no template parameters in scope, then there can't be
12118 any dependent types. */
12119 if (!processing_template_decl)
12122 /* If the type is NULL, we have not computed a type for the entity
12123 in question; in that case, the type is dependent. */
12127 /* Erroneous types can be considered non-dependent. */
12128 if (type == error_mark_node)
12131 /* If we have not already computed the appropriate value for TYPE,
12133 if (!TYPE_DEPENDENT_P_VALID (type))
12135 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
12136 TYPE_DEPENDENT_P_VALID (type) = 1;
12139 return TYPE_DEPENDENT_P (type);
12142 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
12145 dependent_scope_ref_p (tree expression, bool criterion (tree))
12150 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
12152 if (!TYPE_P (TREE_OPERAND (expression, 0)))
12155 scope = TREE_OPERAND (expression, 0);
12156 name = TREE_OPERAND (expression, 1);
12160 An id-expression is type-dependent if it contains a
12161 nested-name-specifier that contains a class-name that names a
12163 /* The suggested resolution to Core Issue 2 implies that if the
12164 qualifying type is the current class, then we must peek
12167 && currently_open_class (scope)
12168 && !criterion (name))
12170 if (dependent_type_p (scope))
12176 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
12177 [temp.dep.constexpr] */
12180 value_dependent_expression_p (tree expression)
12182 if (!processing_template_decl)
12185 /* A name declared with a dependent type. */
12186 if (DECL_P (expression) && type_dependent_expression_p (expression))
12189 switch (TREE_CODE (expression))
12191 case IDENTIFIER_NODE:
12192 /* A name that has not been looked up -- must be dependent. */
12195 case TEMPLATE_PARM_INDEX:
12196 /* A non-type template parm. */
12200 /* A non-type template parm. */
12201 if (DECL_TEMPLATE_PARM_P (expression))
12206 /* A constant with integral or enumeration type and is initialized
12207 with an expression that is value-dependent. */
12208 if (DECL_INITIAL (expression)
12209 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
12210 && value_dependent_expression_p (DECL_INITIAL (expression)))
12214 case DYNAMIC_CAST_EXPR:
12215 case STATIC_CAST_EXPR:
12216 case CONST_CAST_EXPR:
12217 case REINTERPRET_CAST_EXPR:
12219 /* These expressions are value-dependent if the type to which
12220 the cast occurs is dependent or the expression being casted
12221 is value-dependent. */
12223 tree type = TREE_TYPE (expression);
12225 if (dependent_type_p (type))
12228 /* A functional cast has a list of operands. */
12229 expression = TREE_OPERAND (expression, 0);
12232 /* If there are no operands, it must be an expression such
12233 as "int()". This should not happen for aggregate types
12234 because it would form non-constant expressions. */
12235 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12240 if (TREE_CODE (expression) == TREE_LIST)
12242 for (; expression; expression = TREE_CHAIN (expression))
12243 if (value_dependent_expression_p (TREE_VALUE (expression)))
12248 return value_dependent_expression_p (expression);
12253 /* A `sizeof' expression is value-dependent if the operand is
12255 expression = TREE_OPERAND (expression, 0);
12256 if (TYPE_P (expression))
12257 return dependent_type_p (expression);
12258 return type_dependent_expression_p (expression);
12261 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12263 case COMPONENT_REF:
12264 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12265 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12268 /* A CALL_EXPR is value-dependent if any argument is
12269 value-dependent. Why do we have to handle CALL_EXPRs in this
12270 function at all? First, some function calls, those for which
12271 value_dependent_expression_p is true, man appear in constant
12272 expressions. Second, there appear to be bugs which result in
12273 other CALL_EXPRs reaching this point. */
12275 tree function = TREE_OPERAND (expression, 0);
12276 tree args = TREE_OPERAND (expression, 1);
12278 if (value_dependent_expression_p (function))
12284 if (TREE_CODE (args) == TREE_LIST)
12286 for (; args; args = TREE_CHAIN (args))
12287 if (value_dependent_expression_p (TREE_VALUE (args)))
12292 return value_dependent_expression_p (args);
12296 /* A constant expression is value-dependent if any subexpression is
12297 value-dependent. */
12298 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12300 case tcc_reference:
12302 return (value_dependent_expression_p
12303 (TREE_OPERAND (expression, 0)));
12305 case tcc_comparison:
12307 return ((value_dependent_expression_p
12308 (TREE_OPERAND (expression, 0)))
12309 || (value_dependent_expression_p
12310 (TREE_OPERAND (expression, 1))));
12312 case tcc_expression:
12315 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12316 /* In some cases, some of the operands may be missing.
12317 (For example, in the case of PREDECREMENT_EXPR, the
12318 amount to increment by may be missing.) That doesn't
12319 make the expression dependent. */
12320 if (TREE_OPERAND (expression, i)
12321 && (value_dependent_expression_p
12322 (TREE_OPERAND (expression, i))))
12332 /* The expression is not value-dependent. */
12336 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12337 [temp.dep.expr]. */
12340 type_dependent_expression_p (tree expression)
12342 if (!processing_template_decl)
12345 if (expression == error_mark_node)
12348 /* An unresolved name is always dependent. */
12349 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12352 /* Some expression forms are never type-dependent. */
12353 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12354 || TREE_CODE (expression) == SIZEOF_EXPR
12355 || TREE_CODE (expression) == ALIGNOF_EXPR
12356 || TREE_CODE (expression) == TYPEID_EXPR
12357 || TREE_CODE (expression) == DELETE_EXPR
12358 || TREE_CODE (expression) == VEC_DELETE_EXPR
12359 || TREE_CODE (expression) == THROW_EXPR)
12362 /* The types of these expressions depends only on the type to which
12363 the cast occurs. */
12364 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12365 || TREE_CODE (expression) == STATIC_CAST_EXPR
12366 || TREE_CODE (expression) == CONST_CAST_EXPR
12367 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12368 || TREE_CODE (expression) == CAST_EXPR)
12369 return dependent_type_p (TREE_TYPE (expression));
12371 /* The types of these expressions depends only on the type created
12372 by the expression. */
12373 if (TREE_CODE (expression) == NEW_EXPR
12374 || TREE_CODE (expression) == VEC_NEW_EXPR)
12376 /* For NEW_EXPR tree nodes created inside a template, either
12377 the object type itself or a TREE_LIST may appear as the
12379 tree type = TREE_OPERAND (expression, 1);
12380 if (TREE_CODE (type) == TREE_LIST)
12381 /* This is an array type. We need to check array dimensions
12383 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12384 || value_dependent_expression_p
12385 (TREE_OPERAND (TREE_VALUE (type), 1));
12387 return dependent_type_p (type);
12390 if (TREE_CODE (expression) == SCOPE_REF
12391 && dependent_scope_ref_p (expression,
12392 type_dependent_expression_p))
12395 if (TREE_CODE (expression) == FUNCTION_DECL
12396 && DECL_LANG_SPECIFIC (expression)
12397 && DECL_TEMPLATE_INFO (expression)
12398 && (any_dependent_template_arguments_p
12399 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12402 if (TREE_CODE (expression) == TEMPLATE_DECL
12403 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12406 if (TREE_TYPE (expression) == unknown_type_node)
12408 if (TREE_CODE (expression) == ADDR_EXPR)
12409 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12410 if (TREE_CODE (expression) == COMPONENT_REF
12411 || TREE_CODE (expression) == OFFSET_REF)
12413 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12415 expression = TREE_OPERAND (expression, 1);
12416 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12419 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12420 if (TREE_CODE (expression) == SCOPE_REF)
12423 if (TREE_CODE (expression) == BASELINK)
12424 expression = BASELINK_FUNCTIONS (expression);
12426 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12428 if (any_dependent_template_arguments_p
12429 (TREE_OPERAND (expression, 1)))
12431 expression = TREE_OPERAND (expression, 0);
12433 gcc_assert (TREE_CODE (expression) == OVERLOAD
12434 || TREE_CODE (expression) == FUNCTION_DECL);
12438 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12440 expression = OVL_NEXT (expression);
12445 return (dependent_type_p (TREE_TYPE (expression)));
12448 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12449 contains a type-dependent expression. */
12452 any_type_dependent_arguments_p (tree args)
12456 tree arg = TREE_VALUE (args);
12458 if (type_dependent_expression_p (arg))
12460 args = TREE_CHAIN (args);
12465 /* Returns TRUE if the ARG (a template argument) is dependent. */
12468 dependent_template_arg_p (tree arg)
12470 if (!processing_template_decl)
12473 if (TREE_CODE (arg) == TEMPLATE_DECL
12474 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12475 return dependent_template_p (arg);
12476 else if (TYPE_P (arg))
12477 return dependent_type_p (arg);
12479 return (type_dependent_expression_p (arg)
12480 || value_dependent_expression_p (arg));
12483 /* Returns true if ARGS (a collection of template arguments) contains
12484 any dependent arguments. */
12487 any_dependent_template_arguments_p (tree args)
12495 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12497 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12498 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12499 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12506 /* Returns TRUE if the template TMPL is dependent. */
12509 dependent_template_p (tree tmpl)
12511 if (TREE_CODE (tmpl) == OVERLOAD)
12515 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12517 tmpl = OVL_CHAIN (tmpl);
12522 /* Template template parameters are dependent. */
12523 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12524 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12526 /* So are names that have not been looked up. */
12527 if (TREE_CODE (tmpl) == SCOPE_REF
12528 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12530 /* So are member templates of dependent classes. */
12531 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12532 return dependent_type_p (DECL_CONTEXT (tmpl));
12536 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12539 dependent_template_id_p (tree tmpl, tree args)
12541 return (dependent_template_p (tmpl)
12542 || any_dependent_template_arguments_p (args));
12545 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12546 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12547 can be found. Note that this function peers inside uninstantiated
12548 templates and therefore should be used only in extremely limited
12549 situations. ONLY_CURRENT_P restricts this peering to the currently
12550 open classes hierarchy (which is required when comparing types). */
12553 resolve_typename_type (tree type, bool only_current_p)
12561 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12563 scope = TYPE_CONTEXT (type);
12564 name = TYPE_IDENTIFIER (type);
12566 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12567 it first before we can figure out what NAME refers to. */
12568 if (TREE_CODE (scope) == TYPENAME_TYPE)
12569 scope = resolve_typename_type (scope, only_current_p);
12570 /* If we don't know what SCOPE refers to, then we cannot resolve the
12572 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12573 return error_mark_node;
12574 /* If the SCOPE is a template type parameter, we have no way of
12575 resolving the name. */
12576 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12578 /* If the SCOPE is not the current instantiation, there's no reason
12579 to look inside it. */
12580 if (only_current_p && !currently_open_class (scope))
12581 return error_mark_node;
12582 /* If SCOPE is a partial instantiation, it will not have a valid
12583 TYPE_FIELDS list, so use the original template. */
12584 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12585 /* Enter the SCOPE so that name lookup will be resolved as if we
12586 were in the class definition. In particular, SCOPE will no
12587 longer be considered a dependent type. */
12588 pushed_scope = push_scope (scope);
12589 /* Look up the declaration. */
12590 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12591 /* Obtain the set of qualifiers applied to the TYPE. */
12592 quals = cp_type_quals (type);
12593 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12594 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12596 type = error_mark_node;
12597 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12598 && TREE_CODE (decl) == TYPE_DECL)
12599 type = TREE_TYPE (decl);
12600 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12601 && DECL_CLASS_TEMPLATE_P (decl))
12605 /* Obtain the template and the arguments. */
12606 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12607 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12608 /* Instantiate the template. */
12609 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12610 /*entering_scope=*/0, tf_error | tf_user);
12613 type = error_mark_node;
12614 /* Qualify the resulting type. */
12615 if (type != error_mark_node && quals)
12616 type = cp_build_qualified_type (type, quals);
12617 /* Leave the SCOPE. */
12619 pop_scope (pushed_scope);
12624 /* EXPR is an expression which is not type-dependent. Return a proxy
12625 for EXPR that can be used to compute the types of larger
12626 expressions containing EXPR. */
12629 build_non_dependent_expr (tree expr)
12633 /* Preserve null pointer constants so that the type of things like
12634 "p == 0" where "p" is a pointer can be determined. */
12635 if (null_ptr_cst_p (expr))
12637 /* Preserve OVERLOADs; the functions must be available to resolve
12639 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12640 TREE_OPERAND (expr, 0) : expr);
12641 if (is_overloaded_fn (inner_expr)
12642 || TREE_CODE (inner_expr) == OFFSET_REF)
12644 /* There is no need to return a proxy for a variable. */
12645 if (TREE_CODE (expr) == VAR_DECL)
12647 /* Preserve string constants; conversions from string constants to
12648 "char *" are allowed, even though normally a "const char *"
12649 cannot be used to initialize a "char *". */
12650 if (TREE_CODE (expr) == STRING_CST)
12652 /* Preserve arithmetic constants, as an optimization -- there is no
12653 reason to create a new node. */
12654 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12656 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12657 There is at least one place where we want to know that a
12658 particular expression is a throw-expression: when checking a ?:
12659 expression, there are special rules if the second or third
12660 argument is a throw-expression. */
12661 if (TREE_CODE (expr) == THROW_EXPR)
12664 if (TREE_CODE (expr) == COND_EXPR)
12665 return build3 (COND_EXPR,
12667 TREE_OPERAND (expr, 0),
12668 (TREE_OPERAND (expr, 1)
12669 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12670 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12671 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12672 if (TREE_CODE (expr) == COMPOUND_EXPR
12673 && !COMPOUND_EXPR_OVERLOADED (expr))
12674 return build2 (COMPOUND_EXPR,
12676 TREE_OPERAND (expr, 0),
12677 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12679 /* Otherwise, build a NON_DEPENDENT_EXPR.
12681 REFERENCE_TYPEs are not stripped for expressions in templates
12682 because doing so would play havoc with mangling. Consider, for
12685 template <typename T> void f<T& g>() { g(); }
12687 In the body of "f", the expression for "g" will have
12688 REFERENCE_TYPE, even though the standard says that it should
12689 not. The reason is that we must preserve the syntactic form of
12690 the expression so that mangling (say) "f<g>" inside the body of
12691 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12693 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12696 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12697 Return a new TREE_LIST with the various arguments replaced with
12698 equivalent non-dependent expressions. */
12701 build_non_dependent_args (tree args)
12706 new_args = NULL_TREE;
12707 for (a = args; a; a = TREE_CHAIN (a))
12708 new_args = tree_cons (NULL_TREE,
12709 build_non_dependent_expr (TREE_VALUE (a)),
12711 return nreverse (new_args);
12714 #include "gt-cp-pt.h"