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)))
3006 error ("template declaration of %q#D", decl);
3007 return error_mark_node;
3011 /* Check to see that the rules regarding the use of default
3012 arguments are not being violated. */
3013 check_default_tmpl_args (decl, current_template_parms,
3014 primary, is_partial);
3017 return process_partial_specialization (decl);
3019 args = current_template_args ();
3022 || TREE_CODE (ctx) == FUNCTION_DECL
3023 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx))
3024 || (is_friend && !DECL_TEMPLATE_INFO (decl)))
3026 if (DECL_LANG_SPECIFIC (decl)
3027 && DECL_TEMPLATE_INFO (decl)
3028 && DECL_TI_TEMPLATE (decl))
3029 tmpl = DECL_TI_TEMPLATE (decl);
3030 /* If DECL is a TYPE_DECL for a class-template, then there won't
3031 be DECL_LANG_SPECIFIC. The information equivalent to
3032 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */
3033 else if (DECL_IMPLICIT_TYPEDEF_P (decl)
3034 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3035 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3037 /* Since a template declaration already existed for this
3038 class-type, we must be redeclaring it here. Make sure
3039 that the redeclaration is valid. */
3040 redeclare_class_template (TREE_TYPE (decl),
3041 current_template_parms);
3042 /* We don't need to create a new TEMPLATE_DECL; just use the
3043 one we already had. */
3044 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3048 tmpl = build_template_decl (decl, current_template_parms,
3052 if (DECL_LANG_SPECIFIC (decl)
3053 && DECL_TEMPLATE_SPECIALIZATION (decl))
3055 /* A specialization of a member template of a template
3057 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl);
3058 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl);
3059 DECL_TEMPLATE_INFO (decl) = NULL_TREE;
3065 tree a, t, current, parms;
3068 if (TREE_CODE (decl) == TYPE_DECL)
3070 if ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (decl)))
3071 || TREE_CODE (TREE_TYPE (decl)) == ENUMERAL_TYPE)
3072 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl))
3073 && TYPE_TI_TEMPLATE (TREE_TYPE (decl)))
3074 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl));
3077 error ("%qD does not declare a template type", decl);
3081 else if (!DECL_LANG_SPECIFIC (decl) || !DECL_TEMPLATE_INFO (decl))
3083 error ("template definition of non-template %q#D", decl);
3087 tmpl = DECL_TI_TEMPLATE (decl);
3089 if (DECL_FUNCTION_TEMPLATE_P (tmpl)
3090 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl)
3091 && DECL_TEMPLATE_SPECIALIZATION (decl)
3092 && DECL_MEMBER_TEMPLATE_P (tmpl))
3096 /* The declaration is a specialization of a member
3097 template, declared outside the class. Therefore, the
3098 innermost template arguments will be NULL, so we
3099 replace them with the arguments determined by the
3100 earlier call to check_explicit_specialization. */
3101 args = DECL_TI_ARGS (decl);
3104 = build_template_decl (decl, current_template_parms,
3106 DECL_TEMPLATE_RESULT (new_tmpl) = decl;
3107 TREE_TYPE (new_tmpl) = TREE_TYPE (decl);
3108 DECL_TI_TEMPLATE (decl) = new_tmpl;
3109 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl);
3110 DECL_TEMPLATE_INFO (new_tmpl)
3111 = tree_cons (tmpl, args, NULL_TREE);
3113 register_specialization (new_tmpl,
3114 most_general_template (tmpl),
3120 /* Make sure the template headers we got make sense. */
3122 parms = DECL_TEMPLATE_PARMS (tmpl);
3123 i = TMPL_PARMS_DEPTH (parms);
3124 if (TMPL_ARGS_DEPTH (args) != i)
3126 error ("expected %d levels of template parms for %q#D, got %d",
3127 i, decl, TMPL_ARGS_DEPTH (args));
3130 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms))
3132 a = TMPL_ARGS_LEVEL (args, i);
3133 t = INNERMOST_TEMPLATE_PARMS (parms);
3135 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a))
3137 if (current == decl)
3138 error ("got %d template parameters for %q#D",
3139 TREE_VEC_LENGTH (a), decl);
3141 error ("got %d template parameters for %q#T",
3142 TREE_VEC_LENGTH (a), current);
3143 error (" but %d required", TREE_VEC_LENGTH (t));
3144 return error_mark_node;
3147 /* Perhaps we should also check that the parms are used in the
3148 appropriate qualifying scopes in the declarator? */
3150 if (current == decl)
3153 current = TYPE_CONTEXT (current);
3157 DECL_TEMPLATE_RESULT (tmpl) = decl;
3158 TREE_TYPE (tmpl) = TREE_TYPE (decl);
3160 /* Push template declarations for global functions and types. Note
3161 that we do not try to push a global template friend declared in a
3162 template class; such a thing may well depend on the template
3163 parameters of the class. */
3164 if (new_template_p && !ctx
3165 && !(is_friend && template_class_depth (current_class_type) > 0))
3167 tmpl = pushdecl_namespace_level (tmpl, is_friend);
3168 if (tmpl == error_mark_node)
3169 return error_mark_node;
3171 /* Hide template friend classes that haven't been declared yet. */
3172 if (is_friend && TREE_CODE (decl) == TYPE_DECL)
3174 DECL_ANTICIPATED (tmpl) = 1;
3175 DECL_FRIEND_P (tmpl) = 1;
3181 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl;
3182 if (DECL_CONV_FN_P (tmpl))
3184 int depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
3186 /* It is a conversion operator. See if the type converted to
3187 depends on innermost template operands. */
3189 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)),
3191 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1;
3195 /* The DECL_TI_ARGS of DECL contains full set of arguments referring
3196 back to its most general template. If TMPL is a specialization,
3197 ARGS may only have the innermost set of arguments. Add the missing
3198 argument levels if necessary. */
3199 if (DECL_TEMPLATE_INFO (tmpl))
3200 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args);
3202 info = tree_cons (tmpl, args, NULL_TREE);
3204 if (DECL_IMPLICIT_TYPEDEF_P (decl))
3206 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info);
3207 if ((!ctx || TREE_CODE (ctx) != FUNCTION_DECL)
3208 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE
3209 /* Don't change the name if we've already set it up. */
3210 && !IDENTIFIER_TEMPLATE (DECL_NAME (decl)))
3211 DECL_NAME (decl) = classtype_mangled_name (TREE_TYPE (decl));
3213 else if (DECL_LANG_SPECIFIC (decl))
3214 DECL_TEMPLATE_INFO (decl) = info;
3216 return DECL_TEMPLATE_RESULT (tmpl);
3220 push_template_decl (tree decl)
3222 return push_template_decl_real (decl, false);
3225 /* Called when a class template TYPE is redeclared with the indicated
3226 template PARMS, e.g.:
3228 template <class T> struct S;
3229 template <class T> struct S {}; */
3232 redeclare_class_template (tree type, tree parms)
3238 if (!TYPE_TEMPLATE_INFO (type))
3240 error ("%qT is not a template type", type);
3244 tmpl = TYPE_TI_TEMPLATE (type);
3245 if (!PRIMARY_TEMPLATE_P (tmpl))
3246 /* The type is nested in some template class. Nothing to worry
3247 about here; there are no new template parameters for the nested
3253 error ("template specifiers not specified in declaration of %qD",
3258 parms = INNERMOST_TEMPLATE_PARMS (parms);
3259 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl);
3261 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms))
3263 error ("previous declaration %q+D", tmpl);
3264 error ("used %d template parameter(s) instead of %d",
3265 TREE_VEC_LENGTH (tmpl_parms),
3266 TREE_VEC_LENGTH (parms));
3270 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i)
3272 tree tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i));
3273 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
3274 tree tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i));
3275 tree parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i));
3277 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or
3279 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm)
3280 || (TREE_CODE (tmpl_parm) != TYPE_DECL
3281 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))))
3283 error ("template parameter %q+#D", tmpl_parm);
3284 error ("redeclared here as %q#D", parm);
3288 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE)
3290 /* We have in [temp.param]:
3292 A template-parameter may not be given default arguments
3293 by two different declarations in the same scope. */
3294 error ("redefinition of default argument for %q#D", parm);
3295 error ("%J original definition appeared here", tmpl_parm);
3299 if (parm_default != NULL_TREE)
3300 /* Update the previous template parameters (which are the ones
3301 that will really count) with the new default value. */
3302 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default;
3303 else if (tmpl_default != NULL_TREE)
3304 /* Update the new parameters, too; they'll be used as the
3305 parameters for any members. */
3306 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default;
3310 /* Simplify EXPR if it is a non-dependent expression. Returns the
3311 (possibly simplified) expression. */
3314 fold_non_dependent_expr (tree expr)
3316 /* If we're in a template, but EXPR isn't value dependent, simplify
3317 it. We're supposed to treat:
3319 template <typename T> void f(T[1 + 1]);
3320 template <typename T> void f(T[2]);
3322 as two declarations of the same function, for example. */
3323 if (processing_template_decl
3324 && !type_dependent_expression_p (expr)
3325 && !value_dependent_expression_p (expr))
3327 HOST_WIDE_INT saved_processing_template_decl;
3329 saved_processing_template_decl = processing_template_decl;
3330 processing_template_decl = 0;
3331 expr = tsubst_copy_and_build (expr,
3334 /*in_decl=*/NULL_TREE,
3335 /*function_p=*/false);
3336 processing_template_decl = saved_processing_template_decl;
3341 /* EXPR is an expression which is used in a constant-expression context.
3342 For instance, it could be a VAR_DECL with a constant initializer.
3343 Extract the innest constant expression.
3345 This is basically a more powerful version of
3346 integral_constant_value, which can be used also in templates where
3347 initializers can maintain a syntactic rather than semantic form
3348 (even if they are non-dependent, for access-checking purposes). */
3351 fold_decl_constant_value (tree expr)
3353 tree const_expr = expr;
3356 expr = fold_non_dependent_expr (const_expr);
3357 const_expr = integral_constant_value (expr);
3359 while (expr != const_expr);
3364 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which
3365 must be a function or a pointer-to-function type, as specified
3366 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set,
3367 and check that the resulting function has external linkage. */
3370 convert_nontype_argument_function (tree type, tree expr)
3375 fn = instantiate_type (type, fns, tf_none);
3376 if (fn == error_mark_node)
3377 return error_mark_node;
3380 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR)
3381 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0);
3383 /* [temp.arg.nontype]/1
3385 A template-argument for a non-type, non-template template-parameter
3388 -- the address of an object or function with external linkage. */
3389 if (!DECL_EXTERNAL_LINKAGE_P (fn_no_ptr))
3391 error ("%qE is not a valid template argument for type %qT "
3392 "because function %qD has not external linkage",
3393 expr, type, fn_no_ptr);
3400 /* Attempt to convert the non-type template parameter EXPR to the
3401 indicated TYPE. If the conversion is successful, return the
3402 converted value. If the conversion is unsuccessful, return
3403 NULL_TREE if we issued an error message, or error_mark_node if we
3404 did not. We issue error messages for out-and-out bad template
3405 parameters, but not simply because the conversion failed, since we
3406 might be just trying to do argument deduction. Both TYPE and EXPR
3407 must be non-dependent.
3409 The conversion follows the special rules described in
3410 [temp.arg.nontype], and it is much more strict than an implicit
3413 This function is called twice for each template argument (see
3414 lookup_template_class for a more accurate description of this
3415 problem). This means that we need to handle expressions which
3416 are not valid in a C++ source, but can be created from the
3417 first call (for instance, casts to perform conversions). These
3418 hacks can go away after we fix the double coercion problem. */
3421 convert_nontype_argument (tree type, tree expr)
3425 /* Detect immediately string literals as invalid non-type argument.
3426 This special-case is not needed for correctness (we would easily
3427 catch this later), but only to provide better diagnostic for this
3428 common user mistake. As suggested by DR 100, we do not mention
3429 linkage issues in the diagnostic as this is not the point. */
3430 if (TREE_CODE (expr) == STRING_CST)
3432 error ("%qE is not a valid template argument for type %qT "
3433 "because string literals can never be used in this context",
3438 /* If we are in a template, EXPR may be non-dependent, but still
3439 have a syntactic, rather than semantic, form. For example, EXPR
3440 might be a SCOPE_REF, rather than the VAR_DECL to which the
3441 SCOPE_REF refers. Preserving the qualifying scope is necessary
3442 so that access checking can be performed when the template is
3443 instantiated -- but here we need the resolved form so that we can
3444 convert the argument. */
3445 expr = fold_non_dependent_expr (expr);
3446 expr_type = TREE_TYPE (expr);
3448 /* HACK: Due to double coercion, we can get a
3449 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here,
3450 which is the tree that we built on the first call (see
3451 below when coercing to reference to object or to reference to
3452 function). We just strip everything and get to the arg.
3453 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C
3455 if (TREE_CODE (expr) == NOP_EXPR)
3457 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type))
3459 /* ??? Maybe we could use convert_from_reference here, but we
3460 would need to relax its constraints because the NOP_EXPR
3461 could actually change the type to something more cv-qualified,
3462 and this is not folded by convert_from_reference. */
3463 tree addr = TREE_OPERAND (expr, 0);
3464 gcc_assert (TREE_CODE (expr_type) == REFERENCE_TYPE);
3465 gcc_assert (TREE_CODE (addr) == ADDR_EXPR);
3466 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE);
3467 gcc_assert (same_type_ignoring_top_level_qualifiers_p
3468 (TREE_TYPE (expr_type),
3469 TREE_TYPE (TREE_TYPE (addr))));
3471 expr = TREE_OPERAND (addr, 0);
3472 expr_type = TREE_TYPE (expr);
3475 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the
3476 parameter is a pointer to object, through decay and
3477 qualification conversion. Let's strip everything. */
3478 else if (TYPE_PTROBV_P (type))
3481 gcc_assert (TREE_CODE (expr) == ADDR_EXPR);
3482 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE);
3483 /* Skip the ADDR_EXPR only if it is part of the decay for
3484 an array. Otherwise, it is part of the original argument
3485 in the source code. */
3486 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE)
3487 expr = TREE_OPERAND (expr, 0);
3488 expr_type = TREE_TYPE (expr);
3492 /* [temp.arg.nontype]/5, bullet 1
3494 For a non-type template-parameter of integral or enumeration type,
3495 integral promotions (_conv.prom_) and integral conversions
3496 (_conv.integral_) are applied. */
3497 if (INTEGRAL_TYPE_P (type))
3499 if (!INTEGRAL_TYPE_P (expr_type))
3500 return error_mark_node;
3502 expr = fold_decl_constant_value (expr);
3503 /* Notice that there are constant expressions like '4 % 0' which
3504 do not fold into integer constants. */
3505 if (TREE_CODE (expr) != INTEGER_CST)
3507 error ("%qE is not a valid template argument for type %qT "
3508 "because it is a non-constant expression", expr, type);
3512 /* At this point, an implicit conversion does what we want,
3513 because we already know that the expression is of integral
3515 expr = ocp_convert (type, expr, CONV_IMPLICIT, LOOKUP_PROTECT);
3516 if (expr == error_mark_node)
3517 return error_mark_node;
3519 /* Conversion was allowed: fold it to a bare integer constant. */
3522 /* [temp.arg.nontype]/5, bullet 2
3524 For a non-type template-parameter of type pointer to object,
3525 qualification conversions (_conv.qual_) and the array-to-pointer
3526 conversion (_conv.array_) are applied. */
3527 else if (TYPE_PTROBV_P (type))
3529 /* [temp.arg.nontype]/1 (TC1 version, DR 49):
3531 A template-argument for a non-type, non-template template-parameter
3532 shall be one of: [...]
3534 -- the name of a non-type template-parameter;
3535 -- the address of an object or function with external linkage, [...]
3536 expressed as "& id-expression" where the & is optional if the name
3537 refers to a function or array, or if the corresponding
3538 template-parameter is a reference.
3540 Here, we do not care about functions, as they are invalid anyway
3541 for a parameter of type pointer-to-object. */
3542 bool constant_address_p =
3543 (TREE_CODE (expr) == ADDR_EXPR
3544 || TREE_CODE (expr_type) == ARRAY_TYPE
3545 || (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)));
3547 expr = decay_conversion (expr);
3548 if (expr == error_mark_node)
3549 return error_mark_node;
3551 expr = perform_qualification_conversions (type, expr);
3552 if (expr == error_mark_node)
3553 return error_mark_node;
3555 if (!constant_address_p)
3557 error ("%qE is not a valid template argument for type %qT "
3558 "because it is not a constant pointer", expr, type);
3562 /* [temp.arg.nontype]/5, bullet 3
3564 For a non-type template-parameter of type reference to object, no
3565 conversions apply. The type referred to by the reference may be more
3566 cv-qualified than the (otherwise identical) type of the
3567 template-argument. The template-parameter is bound directly to the
3568 template-argument, which must be an lvalue. */
3569 else if (TYPE_REF_OBJ_P (type))
3571 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type),
3573 return error_mark_node;
3575 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
3577 error ("%qE is not a valid template argument for type %qT "
3578 "because of conflicts in cv-qualification", expr, type);
3582 if (!real_lvalue_p (expr))
3584 error ("%qE is not a valid template argument for type %qT "
3585 "because it is not a lvalue", expr, type);
3589 /* [temp.arg.nontype]/1
3591 A template-argument for a non-type, non-template template-parameter
3592 shall be one of: [...]
3594 -- the address of an object or function with external linkage. */
3595 if (!DECL_EXTERNAL_LINKAGE_P (expr))
3597 error ("%qE is not a valid template argument for type %qT "
3598 "because object %qD has not external linkage",
3603 expr = build_nop (type, build_address (expr));
3605 /* [temp.arg.nontype]/5, bullet 4
3607 For a non-type template-parameter of type pointer to function, only
3608 the function-to-pointer conversion (_conv.func_) is applied. If the
3609 template-argument represents a set of overloaded functions (or a
3610 pointer to such), the matching function is selected from the set
3612 else if (TYPE_PTRFN_P (type))
3614 /* If the argument is a template-id, we might not have enough
3615 context information to decay the pointer. */
3616 if (!type_unknown_p (expr_type))
3618 expr = decay_conversion (expr);
3619 if (expr == error_mark_node)
3620 return error_mark_node;
3623 expr = convert_nontype_argument_function (type, expr);
3624 if (!expr || expr == error_mark_node)
3627 /* [temp.arg.nontype]/5, bullet 5
3629 For a non-type template-parameter of type reference to function, no
3630 conversions apply. If the template-argument represents a set of
3631 overloaded functions, the matching function is selected from the set
3633 else if (TYPE_REFFN_P (type))
3635 if (TREE_CODE (expr) == ADDR_EXPR)
3637 error ("%qE is not a valid template argument for type %qT "
3638 "because it is a pointer", expr, type);
3639 inform ("try using %qE instead", TREE_OPERAND (expr, 0));
3643 expr = convert_nontype_argument_function (TREE_TYPE (type), expr);
3644 if (!expr || expr == error_mark_node)
3647 expr = build_nop (type, build_address (expr));
3649 /* [temp.arg.nontype]/5, bullet 6
3651 For a non-type template-parameter of type pointer to member function,
3652 no conversions apply. If the template-argument represents a set of
3653 overloaded member functions, the matching member function is selected
3654 from the set (_over.over_). */
3655 else if (TYPE_PTRMEMFUNC_P (type))
3657 expr = instantiate_type (type, expr, tf_none);
3658 if (expr == error_mark_node)
3659 return error_mark_node;
3661 /* There is no way to disable standard conversions in
3662 resolve_address_of_overloaded_function (called by
3663 instantiate_type). It is possible that the call succeeded by
3664 converting &B::I to &D::I (where B is a base of D), so we need
3665 to reject this conversion here.
3667 Actually, even if there was a way to disable standard conversions,
3668 it would still be better to reject them here so that we can
3669 provide a superior diagnostic. */
3670 if (!same_type_p (TREE_TYPE (expr), type))
3672 /* Make sure we are just one standard conversion off. */
3673 gcc_assert (can_convert (type, TREE_TYPE (expr)));
3674 error ("%qE is not a valid template argument for type %qT "
3675 "because it is of type %qT", expr, type,
3677 inform ("standard conversions are not allowed in this context");
3681 /* [temp.arg.nontype]/5, bullet 7
3683 For a non-type template-parameter of type pointer to data member,
3684 qualification conversions (_conv.qual_) are applied. */
3685 else if (TYPE_PTRMEM_P (type))
3687 expr = perform_qualification_conversions (type, expr);
3688 if (expr == error_mark_node)
3691 /* A template non-type parameter must be one of the above. */
3695 /* Sanity check: did we actually convert the argument to the
3697 gcc_assert (same_type_p (type, TREE_TYPE (expr)));
3702 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for
3703 template template parameters. Both PARM_PARMS and ARG_PARMS are
3704 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL
3707 ARG_PARMS may contain more parameters than PARM_PARMS. If this is
3708 the case, then extra parameters must have default arguments.
3710 Consider the example:
3711 template <class T, class Allocator = allocator> class vector;
3712 template<template <class U> class TT> class C;
3714 C<vector> is a valid instantiation. PARM_PARMS for the above code
3715 contains a TYPE_DECL (for U), ARG_PARMS contains two TYPE_DECLs (for
3716 T and Allocator) and OUTER_ARGS contains the argument that is used to
3717 substitute the TT parameter. */
3720 coerce_template_template_parms (tree parm_parms,
3722 tsubst_flags_t complain,
3726 int nparms, nargs, i;
3729 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC);
3730 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC);
3732 nparms = TREE_VEC_LENGTH (parm_parms);
3733 nargs = TREE_VEC_LENGTH (arg_parms);
3735 /* The rule here is opposite of coerce_template_parms. */
3738 && TREE_PURPOSE (TREE_VEC_ELT (arg_parms, nparms)) == NULL_TREE))
3741 for (i = 0; i < nparms; ++i)
3743 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i));
3744 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i));
3746 if (arg == NULL_TREE || arg == error_mark_node
3747 || parm == NULL_TREE || parm == error_mark_node)
3750 if (TREE_CODE (arg) != TREE_CODE (parm))
3753 switch (TREE_CODE (parm))
3759 /* We encounter instantiations of templates like
3760 template <template <template <class> class> class TT>
3763 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3764 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3766 if (!coerce_template_template_parms
3767 (parmparm, argparm, complain, in_decl, outer_args))
3773 /* The tsubst call is used to handle cases such as
3775 template <int> class C {};
3776 template <class T, template <T> class TT> class D {};
3779 i.e. the parameter list of TT depends on earlier parameters. */
3780 if (!dependent_type_p (TREE_TYPE (arg))
3782 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl),
3794 /* Convert the indicated template ARG as necessary to match the
3795 indicated template PARM. Returns the converted ARG, or
3796 error_mark_node if the conversion was unsuccessful. Error and
3797 warning messages are issued under control of COMPLAIN. This
3798 conversion is for the Ith parameter in the parameter list. ARGS is
3799 the full set of template arguments deduced so far. */
3802 convert_template_argument (tree parm,
3805 tsubst_flags_t complain,
3811 int is_type, requires_type, is_tmpl_type, requires_tmpl_type;
3813 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3815 if (TREE_CODE (arg) == TREE_LIST
3816 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF)
3818 /* The template argument was the name of some
3819 member function. That's usually
3820 invalid, but static members are OK. In any
3821 case, grab the underlying fields/functions
3822 and issue an error later if required. */
3823 arg = TREE_VALUE (arg);
3824 TREE_TYPE (arg) = unknown_type_node;
3827 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL;
3828 requires_type = (TREE_CODE (parm) == TYPE_DECL
3829 || requires_tmpl_type);
3831 is_tmpl_type = ((TREE_CODE (arg) == TEMPLATE_DECL
3832 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL)
3833 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3834 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE);
3837 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM
3838 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE))
3839 arg = TYPE_STUB_DECL (arg);
3841 is_type = TYPE_P (arg) || is_tmpl_type;
3843 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF
3844 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM)
3846 pedwarn ("to refer to a type member of a template parameter, "
3847 "use %<typename %E%>", arg);
3849 arg = make_typename_type (TREE_OPERAND (arg, 0),
3850 TREE_OPERAND (arg, 1),
3852 complain & tf_error);
3855 if (is_type != requires_type)
3859 if (complain & tf_error)
3861 error ("type/value mismatch at argument %d in template "
3862 "parameter list for %qD",
3865 error (" expected a constant of type %qT, got %qT",
3867 (is_tmpl_type ? DECL_NAME (arg) : arg));
3868 else if (requires_tmpl_type)
3869 error (" expected a class template, got %qE", arg);
3871 error (" expected a type, got %qE", arg);
3874 return error_mark_node;
3876 if (is_tmpl_type ^ requires_tmpl_type)
3878 if (in_decl && (complain & tf_error))
3880 error ("type/value mismatch at argument %d in template "
3881 "parameter list for %qD",
3884 error (" expected a type, got %qT", DECL_NAME (arg));
3886 error (" expected a class template, got %qT", arg);
3888 return error_mark_node;
3893 if (requires_tmpl_type)
3895 if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE)
3896 /* The number of argument required is not known yet.
3897 Just accept it for now. */
3898 val = TREE_TYPE (arg);
3901 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm);
3902 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg);
3904 if (coerce_template_template_parms (parmparm, argparm,
3910 /* TEMPLATE_TEMPLATE_PARM node is preferred over
3912 if (val != error_mark_node
3913 && DECL_TEMPLATE_TEMPLATE_PARM_P (val))
3914 val = TREE_TYPE (val);
3918 if (in_decl && (complain & tf_error))
3920 error ("type/value mismatch at argument %d in "
3921 "template parameter list for %qD",
3923 error (" expected a template of type %qD, got %qD",
3927 val = error_mark_node;
3933 /* We only form one instance of each template specialization.
3934 Therefore, if we use a non-canonical variant (i.e., a
3935 typedef), any future messages referring to the type will use
3936 the typedef, which is confusing if those future uses do not
3937 themselves also use the typedef. */
3939 val = canonical_type_variant (val);
3943 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl);
3945 if (invalid_nontype_parm_type_p (t, complain))
3946 return error_mark_node;
3948 if (!uses_template_parms (arg) && !uses_template_parms (t))
3949 /* We used to call digest_init here. However, digest_init
3950 will report errors, which we don't want when complain
3951 is zero. More importantly, digest_init will try too
3952 hard to convert things: for example, `0' should not be
3953 converted to pointer type at this point according to
3954 the standard. Accepting this is not merely an
3955 extension, since deciding whether or not these
3956 conversions can occur is part of determining which
3957 function template to call, or whether a given explicit
3958 argument specification is valid. */
3959 val = convert_nontype_argument (t, arg);
3963 if (val == NULL_TREE)
3964 val = error_mark_node;
3965 else if (val == error_mark_node && (complain & tf_error))
3966 error ("could not convert template argument %qE to %qT", arg, t);
3972 /* Convert all template arguments to their appropriate types, and
3973 return a vector containing the innermost resulting template
3974 arguments. If any error occurs, return error_mark_node. Error and
3975 warning messages are issued under control of COMPLAIN.
3977 If REQUIRE_ALL_ARGUMENTS is nonzero, all arguments must be
3978 provided in ARGLIST, or else trailing parameters must have default
3979 values. If REQUIRE_ALL_ARGUMENTS is zero, we will attempt argument
3980 deduction for any unspecified trailing arguments. */
3983 coerce_template_parms (tree parms,
3986 tsubst_flags_t complain,
3987 int require_all_arguments)
3989 int nparms, nargs, i, lost = 0;
3992 tree new_inner_args;
3994 inner_args = INNERMOST_TEMPLATE_ARGS (args);
3995 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0;
3996 nparms = TREE_VEC_LENGTH (parms);
4000 && require_all_arguments
4001 && TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)) == NULL_TREE))
4003 if (complain & tf_error)
4005 error ("wrong number of template arguments (%d, should be %d)",
4009 error ("provided for %q+D", in_decl);
4012 return error_mark_node;
4015 new_inner_args = make_tree_vec (nparms);
4016 new_args = add_outermost_template_args (args, new_inner_args);
4017 for (i = 0; i < nparms; i++)
4022 /* Get the Ith template parameter. */
4023 parm = TREE_VEC_ELT (parms, i);
4025 /* Calculate the Ith argument. */
4027 arg = TREE_VEC_ELT (inner_args, i);
4028 else if (require_all_arguments)
4029 /* There must be a default arg in this case. */
4030 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args,
4036 if (arg == error_mark_node)
4038 if (complain & tf_error)
4039 error ("template argument %d is invalid", i + 1);
4042 arg = convert_template_argument (TREE_VALUE (parm),
4043 arg, new_args, complain, i,
4046 if (arg == error_mark_node)
4048 TREE_VEC_ELT (new_inner_args, i) = arg;
4052 return error_mark_node;
4054 return new_inner_args;
4057 /* Returns 1 if template args OT and NT are equivalent. */
4060 template_args_equal (tree ot, tree nt)
4065 if (TREE_CODE (nt) == TREE_VEC)
4066 /* For member templates */
4067 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt);
4068 else if (TYPE_P (nt))
4069 return TYPE_P (ot) && same_type_p (ot, nt);
4070 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot))
4073 return cp_tree_equal (ot, nt);
4076 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets
4077 of template arguments. Returns 0 otherwise. */
4080 comp_template_args (tree oldargs, tree newargs)
4084 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs))
4087 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i)
4089 tree nt = TREE_VEC_ELT (newargs, i);
4090 tree ot = TREE_VEC_ELT (oldargs, i);
4092 if (! template_args_equal (ot, nt))
4098 /* Given class template name and parameter list, produce a user-friendly name
4099 for the instantiation. */
4102 mangle_class_name_for_template (const char* name, tree parms, tree arglist)
4104 static struct obstack scratch_obstack;
4105 static char *scratch_firstobj;
4108 if (!scratch_firstobj)
4109 gcc_obstack_init (&scratch_obstack);
4111 obstack_free (&scratch_obstack, scratch_firstobj);
4112 scratch_firstobj = obstack_alloc (&scratch_obstack, 1);
4114 #define ccat(C) obstack_1grow (&scratch_obstack, (C));
4115 #define cat(S) obstack_grow (&scratch_obstack, (S), strlen (S))
4119 nparms = TREE_VEC_LENGTH (parms);
4120 arglist = INNERMOST_TEMPLATE_ARGS (arglist);
4121 gcc_assert (nparms == TREE_VEC_LENGTH (arglist));
4122 for (i = 0; i < nparms; i++)
4124 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i));
4125 tree arg = TREE_VEC_ELT (arglist, i);
4130 if (TREE_CODE (parm) == TYPE_DECL)
4132 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4135 else if (TREE_CODE (parm) == TEMPLATE_DECL)
4137 if (TREE_CODE (arg) == TEMPLATE_DECL)
4139 /* Already substituted with real template. Just output
4140 the template name here */
4141 tree context = DECL_CONTEXT (arg);
4144 /* The template may be defined in a namespace, or
4145 may be a member template. */
4146 gcc_assert (TREE_CODE (context) == NAMESPACE_DECL
4147 || CLASS_TYPE_P (context));
4148 cat (decl_as_string (DECL_CONTEXT (arg),
4149 TFF_PLAIN_IDENTIFIER));
4152 cat (IDENTIFIER_POINTER (DECL_NAME (arg)));
4155 /* Output the parameter declaration. */
4156 cat (type_as_string (arg, TFF_CHASE_TYPEDEF));
4160 gcc_assert (TREE_CODE (parm) == PARM_DECL);
4162 /* No need to check arglist against parmlist here; we did that
4163 in coerce_template_parms, called from lookup_template_class. */
4164 cat (expr_as_string (arg, TFF_PLAIN_IDENTIFIER));
4167 char *bufp = obstack_next_free (&scratch_obstack);
4169 while (bufp[offset - 1] == ' ')
4171 obstack_blank_fast (&scratch_obstack, offset);
4173 /* B<C<char> >, not B<C<char>> */
4174 if (bufp[offset - 1] == '>')
4179 return (char *) obstack_base (&scratch_obstack);
4183 classtype_mangled_name (tree t)
4185 if (CLASSTYPE_TEMPLATE_INFO (t)
4186 /* Specializations have already had their names set up in
4187 lookup_template_class. */
4188 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
4190 tree tmpl = most_general_template (CLASSTYPE_TI_TEMPLATE (t));
4192 /* For non-primary templates, the template parameters are
4193 implicit from their surrounding context. */
4194 if (PRIMARY_TEMPLATE_P (tmpl))
4196 tree name = DECL_NAME (tmpl);
4197 char *mangled_name = mangle_class_name_for_template
4198 (IDENTIFIER_POINTER (name),
4199 DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
4200 CLASSTYPE_TI_ARGS (t));
4201 tree id = get_identifier (mangled_name);
4202 IDENTIFIER_TEMPLATE (id) = name;
4207 return TYPE_IDENTIFIER (t);
4211 add_pending_template (tree d)
4213 tree ti = (TYPE_P (d)
4214 ? CLASSTYPE_TEMPLATE_INFO (d)
4215 : DECL_TEMPLATE_INFO (d));
4219 if (TI_PENDING_TEMPLATE_FLAG (ti))
4222 /* We are called both from instantiate_decl, where we've already had a
4223 tinst_level pushed, and instantiate_template, where we haven't.
4225 level = !(current_tinst_level && TINST_DECL (current_tinst_level) == d);
4228 push_tinst_level (d);
4230 pt = tree_cons (current_tinst_level, d, NULL_TREE);
4231 if (last_pending_template)
4232 TREE_CHAIN (last_pending_template) = pt;
4234 pending_templates = pt;
4236 last_pending_template = pt;
4238 TI_PENDING_TEMPLATE_FLAG (ti) = 1;
4245 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and
4246 ARGLIST. Valid choices for FNS are given in the cp-tree.def
4247 documentation for TEMPLATE_ID_EXPR. */
4250 lookup_template_function (tree fns, tree arglist)
4254 if (fns == error_mark_node || arglist == error_mark_node)
4255 return error_mark_node;
4257 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC);
4258 gcc_assert (fns && (is_overloaded_fn (fns)
4259 || TREE_CODE (fns) == IDENTIFIER_NODE));
4261 if (BASELINK_P (fns))
4263 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR,
4265 BASELINK_FUNCTIONS (fns),
4270 type = TREE_TYPE (fns);
4271 if (TREE_CODE (fns) == OVERLOAD || !type)
4272 type = unknown_type_node;
4274 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist);
4277 /* Within the scope of a template class S<T>, the name S gets bound
4278 (in build_self_reference) to a TYPE_DECL for the class, not a
4279 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type,
4280 or one of its enclosing classes, and that type is a template,
4281 return the associated TEMPLATE_DECL. Otherwise, the original
4282 DECL is returned. */
4285 maybe_get_template_decl_from_type_decl (tree decl)
4287 return (decl != NULL_TREE
4288 && TREE_CODE (decl) == TYPE_DECL
4289 && DECL_ARTIFICIAL (decl)
4290 && CLASS_TYPE_P (TREE_TYPE (decl))
4291 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl)))
4292 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl;
4295 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of
4296 parameters, find the desired type.
4298 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments.
4300 IN_DECL, if non-NULL, is the template declaration we are trying to
4303 If ENTERING_SCOPE is nonzero, we are about to enter the scope of
4304 the class we are looking up.
4306 Issue error and warning messages under control of COMPLAIN.
4308 If the template class is really a local class in a template
4309 function, then the FUNCTION_CONTEXT is the function in which it is
4312 ??? Note that this function is currently called *twice* for each
4313 template-id: the first time from the parser, while creating the
4314 incomplete type (finish_template_type), and the second type during the
4315 real instantiation (instantiate_template_class). This is surely something
4316 that we want to avoid. It also causes some problems with argument
4317 coercion (see convert_nontype_argument for more information on this). */
4320 lookup_template_class (tree d1,
4325 tsubst_flags_t complain)
4327 tree template = NULL_TREE, parmlist;
4330 timevar_push (TV_NAME_LOOKUP);
4332 if (TREE_CODE (d1) == IDENTIFIER_NODE)
4334 tree value = innermost_non_namespace_value (d1);
4335 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value))
4340 push_decl_namespace (context);
4341 template = lookup_name (d1, /*prefer_type=*/0);
4342 template = maybe_get_template_decl_from_type_decl (template);
4344 pop_decl_namespace ();
4347 context = DECL_CONTEXT (template);
4349 else if (TREE_CODE (d1) == TYPE_DECL && IS_AGGR_TYPE (TREE_TYPE (d1)))
4351 tree type = TREE_TYPE (d1);
4353 /* If we are declaring a constructor, say A<T>::A<T>, we will get
4354 an implicit typename for the second A. Deal with it. */
4355 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type))
4356 type = TREE_TYPE (type);
4358 if (CLASSTYPE_TEMPLATE_INFO (type))
4360 template = CLASSTYPE_TI_TEMPLATE (type);
4361 d1 = DECL_NAME (template);
4364 else if (TREE_CODE (d1) == ENUMERAL_TYPE
4365 || (TYPE_P (d1) && IS_AGGR_TYPE (d1)))
4367 template = TYPE_TI_TEMPLATE (d1);
4368 d1 = DECL_NAME (template);
4370 else if (TREE_CODE (d1) == TEMPLATE_DECL
4371 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL)
4374 d1 = DECL_NAME (template);
4375 context = DECL_CONTEXT (template);
4378 /* Issue an error message if we didn't find a template. */
4381 if (complain & tf_error)
4382 error ("%qT is not a template", d1);
4383 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4386 if (TREE_CODE (template) != TEMPLATE_DECL
4387 /* Make sure it's a user visible template, if it was named by
4389 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (template)
4390 && !PRIMARY_TEMPLATE_P (template)))
4392 if (complain & tf_error)
4394 error ("non-template type %qT used as a template", d1);
4396 error ("for template declaration %q+D", in_decl);
4398 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4401 complain &= ~tf_user;
4403 if (DECL_TEMPLATE_TEMPLATE_PARM_P (template))
4405 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store
4406 template arguments */
4411 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (template);
4413 /* Consider an example where a template template parameter declared as
4415 template <class T, class U = std::allocator<T> > class TT
4417 The template parameter level of T and U are one level larger than
4418 of TT. To proper process the default argument of U, say when an
4419 instantiation `TT<int>' is seen, we need to build the full
4420 arguments containing {int} as the innermost level. Outer levels,
4421 available when not appearing as default template argument, can be
4422 obtained from `current_template_args ()'.
4424 Suppose that TT is later substituted with std::vector. The above
4425 instantiation is `TT<int, std::allocator<T> >' with TT at
4426 level 1, and T at level 2, while the template arguments at level 1
4427 becomes {std::vector} and the inner level 2 is {int}. */
4429 if (current_template_parms)
4430 arglist = add_to_template_args (current_template_args (), arglist);
4432 arglist2 = coerce_template_parms (parmlist, arglist, template,
4433 complain, /*require_all_args=*/1);
4434 if (arglist2 == error_mark_node
4435 || (!uses_template_parms (arglist2)
4436 && check_instantiated_args (template, arglist2, complain)))
4437 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4439 parm = bind_template_template_parm (TREE_TYPE (template), arglist2);
4440 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, parm);
4444 tree template_type = TREE_TYPE (template);
4447 tree found = NULL_TREE;
4450 int is_partial_instantiation;
4452 gen_tmpl = most_general_template (template);
4453 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl);
4454 parm_depth = TMPL_PARMS_DEPTH (parmlist);
4455 arg_depth = TMPL_ARGS_DEPTH (arglist);
4457 if (arg_depth == 1 && parm_depth > 1)
4459 /* We've been given an incomplete set of template arguments.
4462 template <class T> struct S1 {
4463 template <class U> struct S2 {};
4464 template <class U> struct S2<U*> {};
4467 we will be called with an ARGLIST of `U*', but the
4468 TEMPLATE will be `template <class T> template
4469 <class U> struct S1<T>::S2'. We must fill in the missing
4472 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (template)),
4474 arg_depth = TMPL_ARGS_DEPTH (arglist);
4477 /* Now we should have enough arguments. */
4478 gcc_assert (parm_depth == arg_depth);
4480 /* From here on, we're only interested in the most general
4482 template = gen_tmpl;
4484 /* Calculate the BOUND_ARGS. These will be the args that are
4485 actually tsubst'd into the definition to create the
4489 /* We have multiple levels of arguments to coerce, at once. */
4491 int saved_depth = TMPL_ARGS_DEPTH (arglist);
4493 tree bound_args = make_tree_vec (parm_depth);
4495 for (i = saved_depth,
4496 t = DECL_TEMPLATE_PARMS (template);
4497 i > 0 && t != NULL_TREE;
4498 --i, t = TREE_CHAIN (t))
4500 tree a = coerce_template_parms (TREE_VALUE (t),
4502 complain, /*require_all_args=*/1);
4504 /* Don't process further if one of the levels fails. */
4505 if (a == error_mark_node)
4507 /* Restore the ARGLIST to its full size. */
4508 TREE_VEC_LENGTH (arglist) = saved_depth;
4509 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4512 SET_TMPL_ARGS_LEVEL (bound_args, i, a);
4514 /* We temporarily reduce the length of the ARGLIST so
4515 that coerce_template_parms will see only the arguments
4516 corresponding to the template parameters it is
4518 TREE_VEC_LENGTH (arglist)--;
4521 /* Restore the ARGLIST to its full size. */
4522 TREE_VEC_LENGTH (arglist) = saved_depth;
4524 arglist = bound_args;
4528 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist),
4529 INNERMOST_TEMPLATE_ARGS (arglist),
4531 complain, /*require_all_args=*/1);
4533 if (arglist == error_mark_node)
4534 /* We were unable to bind the arguments. */
4535 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4537 /* In the scope of a template class, explicit references to the
4538 template class refer to the type of the template, not any
4539 instantiation of it. For example, in:
4541 template <class T> class C { void f(C<T>); }
4543 the `C<T>' is just the same as `C'. Outside of the
4544 class, however, such a reference is an instantiation. */
4545 if (comp_template_args (TYPE_TI_ARGS (template_type),
4548 found = template_type;
4550 if (!entering_scope && PRIMARY_TEMPLATE_P (template))
4554 for (ctx = current_class_type;
4555 ctx && TREE_CODE (ctx) != NAMESPACE_DECL;
4557 ? TYPE_CONTEXT (ctx)
4558 : DECL_CONTEXT (ctx)))
4559 if (TYPE_P (ctx) && same_type_p (ctx, template_type))
4562 /* We're not in the scope of the class, so the
4563 TEMPLATE_TYPE is not the type we want after all. */
4569 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4571 /* If we already have this specialization, return it. */
4572 found = retrieve_specialization (template, arglist,
4573 /*class_specializations_p=*/false);
4575 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4577 /* This type is a "partial instantiation" if any of the template
4578 arguments still involve template parameters. Note that we set
4579 IS_PARTIAL_INSTANTIATION for partial specializations as
4581 is_partial_instantiation = uses_template_parms (arglist);
4583 /* If the deduced arguments are invalid, then the binding
4585 if (!is_partial_instantiation
4586 && check_instantiated_args (template,
4587 INNERMOST_TEMPLATE_ARGS (arglist),
4589 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, error_mark_node);
4591 if (!is_partial_instantiation
4592 && !PRIMARY_TEMPLATE_P (template)
4593 && TREE_CODE (CP_DECL_CONTEXT (template)) == NAMESPACE_DECL)
4595 found = xref_tag_from_type (TREE_TYPE (template),
4596 DECL_NAME (template),
4597 /*tag_scope=*/ts_global);
4598 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, found);
4601 context = tsubst (DECL_CONTEXT (template), arglist,
4604 context = global_namespace;
4606 /* Create the type. */
4607 if (TREE_CODE (template_type) == ENUMERAL_TYPE)
4609 if (!is_partial_instantiation)
4611 set_current_access_from_decl (TYPE_NAME (template_type));
4612 t = start_enum (TYPE_IDENTIFIER (template_type));
4615 /* We don't want to call start_enum for this type, since
4616 the values for the enumeration constants may involve
4617 template parameters. And, no one should be interested
4618 in the enumeration constants for such a type. */
4619 t = make_node (ENUMERAL_TYPE);
4623 t = make_aggr_type (TREE_CODE (template_type));
4624 CLASSTYPE_DECLARED_CLASS (t)
4625 = CLASSTYPE_DECLARED_CLASS (template_type);
4626 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t);
4627 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type);
4629 /* A local class. Make sure the decl gets registered properly. */
4630 if (context == current_function_decl)
4631 pushtag (DECL_NAME (template), t, /*tag_scope=*/ts_current);
4634 /* If we called start_enum or pushtag above, this information
4635 will already be set up. */
4638 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4640 type_decl = create_implicit_typedef (DECL_NAME (template), t);
4641 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t);
4642 TYPE_STUB_DECL (t) = type_decl;
4643 DECL_SOURCE_LOCATION (type_decl)
4644 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type));
4647 type_decl = TYPE_NAME (t);
4649 TREE_PRIVATE (type_decl)
4650 = TREE_PRIVATE (TYPE_STUB_DECL (template_type));
4651 TREE_PROTECTED (type_decl)
4652 = TREE_PROTECTED (TYPE_STUB_DECL (template_type));
4653 DECL_IN_SYSTEM_HEADER (type_decl)
4654 = DECL_IN_SYSTEM_HEADER (template);
4655 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type))
4657 DECL_VISIBILITY_SPECIFIED (type_decl) = 1;
4658 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type);
4661 /* Set up the template information. We have to figure out which
4662 template is the immediate parent if this is a full
4664 if (parm_depth == 1 || is_partial_instantiation
4665 || !PRIMARY_TEMPLATE_P (template))
4666 /* This case is easy; there are no member templates involved. */
4670 /* This is a full instantiation of a member template. Look
4671 for a partial instantiation of which this is an instance. */
4673 for (found = DECL_TEMPLATE_INSTANTIATIONS (template);
4674 found; found = TREE_CHAIN (found))
4677 tree tmpl = CLASSTYPE_TI_TEMPLATE (TREE_VALUE (found));
4679 /* We only want partial instantiations, here, not
4680 specializations or full instantiations. */
4681 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_VALUE (found))
4682 || !uses_template_parms (TREE_VALUE (found)))
4685 /* Temporarily reduce by one the number of levels in the
4686 ARGLIST and in FOUND so as to avoid comparing the
4687 last set of arguments. */
4688 TREE_VEC_LENGTH (arglist)--;
4689 TREE_VEC_LENGTH (TREE_PURPOSE (found)) --;
4691 /* See if the arguments match. If they do, then TMPL is
4692 the partial instantiation we want. */
4693 success = comp_template_args (TREE_PURPOSE (found), arglist);
4695 /* Restore the argument vectors to their full size. */
4696 TREE_VEC_LENGTH (arglist)++;
4697 TREE_VEC_LENGTH (TREE_PURPOSE (found))++;
4708 /* There was no partial instantiation. This happens
4709 where C<T> is a member template of A<T> and it's used
4712 template <typename T> struct B { A<T>::C<int> m; };
4715 Create the partial instantiation.
4717 TREE_VEC_LENGTH (arglist)--;
4718 found = tsubst (template, arglist, complain, NULL_TREE);
4719 TREE_VEC_LENGTH (arglist)++;
4723 SET_TYPE_TEMPLATE_INFO (t, tree_cons (found, arglist, NULL_TREE));
4724 DECL_TEMPLATE_INSTANTIATIONS (template)
4725 = tree_cons (arglist, t,
4726 DECL_TEMPLATE_INSTANTIATIONS (template));
4728 if (TREE_CODE (t) == ENUMERAL_TYPE
4729 && !is_partial_instantiation)
4730 /* Now that the type has been registered on the instantiations
4731 list, we set up the enumerators. Because the enumeration
4732 constants may involve the enumeration type itself, we make
4733 sure to register the type first, and then create the
4734 constants. That way, doing tsubst_expr for the enumeration
4735 constants won't result in recursive calls here; we'll find
4736 the instantiation and exit above. */
4737 tsubst_enum (template_type, t, arglist);
4739 /* Reset the name of the type, now that CLASSTYPE_TEMPLATE_INFO
4741 if (TREE_CODE (t) != ENUMERAL_TYPE)
4742 DECL_NAME (type_decl) = classtype_mangled_name (t);
4743 if (is_partial_instantiation)
4744 /* If the type makes use of template parameters, the
4745 code that generates debugging information will crash. */
4746 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1;
4748 POP_TIMEVAR_AND_RETURN (TV_NAME_LOOKUP, t);
4750 timevar_pop (TV_NAME_LOOKUP);
4757 struct pointer_set_t *visited;
4760 /* Called from for_each_template_parm via walk_tree. */
4763 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d)
4766 struct pair_fn_data *pfd = (struct pair_fn_data *) d;
4767 tree_fn_t fn = pfd->fn;
4768 void *data = pfd->data;
4771 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited))
4772 return error_mark_node;
4774 switch (TREE_CODE (t))
4777 if (TYPE_PTRMEMFUNC_P (t))
4783 if (!TYPE_TEMPLATE_INFO (t))
4785 else if (for_each_template_parm (TREE_VALUE (TYPE_TEMPLATE_INFO (t)),
4786 fn, data, pfd->visited))
4787 return error_mark_node;
4791 /* Since we're not going to walk subtrees, we have to do this
4793 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data,
4795 return error_mark_node;
4799 /* Check the return type. */
4800 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4801 return error_mark_node;
4803 /* Check the parameter types. Since default arguments are not
4804 instantiated until they are needed, the TYPE_ARG_TYPES may
4805 contain expressions that involve template parameters. But,
4806 no-one should be looking at them yet. And, once they're
4807 instantiated, they don't contain template parameters, so
4808 there's no point in looking at them then, either. */
4812 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm))
4813 if (for_each_template_parm (TREE_VALUE (parm), fn, data,
4815 return error_mark_node;
4817 /* Since we've already handled the TYPE_ARG_TYPES, we don't
4818 want walk_tree walking into them itself. */
4824 if (for_each_template_parm (TYPE_FIELDS (t), fn, data,
4826 return error_mark_node;
4831 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)
4832 && for_each_template_parm (DECL_TI_ARGS (t), fn, data,
4834 return error_mark_node;
4839 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t)
4840 && for_each_template_parm (DECL_INITIAL (t), fn, data,
4842 return error_mark_node;
4843 if (DECL_CONTEXT (t)
4844 && for_each_template_parm (DECL_CONTEXT (t), fn, data,
4846 return error_mark_node;
4849 case BOUND_TEMPLATE_TEMPLATE_PARM:
4850 /* Record template parameters such as `T' inside `TT<T>'. */
4851 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited))
4852 return error_mark_node;
4855 case TEMPLATE_TEMPLATE_PARM:
4856 case TEMPLATE_TYPE_PARM:
4857 case TEMPLATE_PARM_INDEX:
4858 if (fn && (*fn)(t, data))
4859 return error_mark_node;
4861 return error_mark_node;
4865 /* A template template parameter is encountered. */
4866 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)
4867 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited))
4868 return error_mark_node;
4870 /* Already substituted template template parameter */
4876 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn,
4877 data, pfd->visited))
4878 return error_mark_node;
4882 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t))
4883 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE
4884 (TREE_TYPE (t)), fn, data,
4886 return error_mark_node;
4891 /* If there's no type, then this thing must be some expression
4892 involving template parameters. */
4893 if (!fn && !TREE_TYPE (t))
4894 return error_mark_node;
4899 case REINTERPRET_CAST_EXPR:
4900 case CONST_CAST_EXPR:
4901 case STATIC_CAST_EXPR:
4902 case DYNAMIC_CAST_EXPR:
4906 case PSEUDO_DTOR_EXPR:
4908 return error_mark_node;
4912 /* If we do not handle this case specially, we end up walking
4913 the BINFO hierarchy, which is circular, and therefore
4914 confuses walk_tree. */
4916 if (for_each_template_parm (BASELINK_FUNCTIONS (*tp), fn, data,
4918 return error_mark_node;
4925 /* We didn't find any template parameters we liked. */
4929 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM,
4930 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T,
4931 call FN with the parameter and the DATA.
4932 If FN returns nonzero, the iteration is terminated, and
4933 for_each_template_parm returns 1. Otherwise, the iteration
4934 continues. If FN never returns a nonzero value, the value
4935 returned by for_each_template_parm is 0. If FN is NULL, it is
4936 considered to be the function which always returns 1. */
4939 for_each_template_parm (tree t, tree_fn_t fn, void* data,
4940 struct pointer_set_t *visited)
4942 struct pair_fn_data pfd;
4949 /* Walk the tree. (Conceptually, we would like to walk without
4950 duplicates, but for_each_template_parm_r recursively calls
4951 for_each_template_parm, so we would need to reorganize a fair
4952 bit to use walk_tree_without_duplicates, so we keep our own
4955 pfd.visited = visited;
4957 pfd.visited = pointer_set_create ();
4958 result = walk_tree (&t,
4959 for_each_template_parm_r,
4961 pfd.visited) != NULL_TREE;
4966 pointer_set_destroy (pfd.visited);
4973 /* Returns true if T depends on any template parameter. */
4976 uses_template_parms (tree t)
4979 int saved_processing_template_decl;
4981 saved_processing_template_decl = processing_template_decl;
4982 if (!saved_processing_template_decl)
4983 processing_template_decl = 1;
4985 dependent_p = dependent_type_p (t);
4986 else if (TREE_CODE (t) == TREE_VEC)
4987 dependent_p = any_dependent_template_arguments_p (t);
4988 else if (TREE_CODE (t) == TREE_LIST)
4989 dependent_p = (uses_template_parms (TREE_VALUE (t))
4990 || uses_template_parms (TREE_CHAIN (t)));
4991 else if (TREE_CODE (t) == TYPE_DECL)
4992 dependent_p = dependent_type_p (TREE_TYPE (t));
4995 || TREE_CODE (t) == TEMPLATE_PARM_INDEX
4996 || TREE_CODE (t) == OVERLOAD
4997 || TREE_CODE (t) == BASELINK
4998 || TREE_CODE (t) == IDENTIFIER_NODE
4999 || CONSTANT_CLASS_P (t))
5000 dependent_p = (type_dependent_expression_p (t)
5001 || value_dependent_expression_p (t));
5004 gcc_assert (t == error_mark_node);
5005 dependent_p = false;
5008 processing_template_decl = saved_processing_template_decl;
5013 /* Returns true if T depends on any template parameter with level LEVEL. */
5016 uses_template_parms_level (tree t, int level)
5018 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL);
5021 static int tinst_depth;
5022 extern int max_tinst_depth;
5023 #ifdef GATHER_STATISTICS
5026 static int tinst_level_tick;
5027 static int last_template_error_tick;
5029 /* We're starting to instantiate D; record the template instantiation context
5030 for diagnostics and to restore it later. */
5033 push_tinst_level (tree d)
5037 if (tinst_depth >= max_tinst_depth)
5039 /* If the instantiation in question still has unbound template parms,
5040 we don't really care if we can't instantiate it, so just return.
5041 This happens with base instantiation for implicit `typename'. */
5042 if (uses_template_parms (d))
5045 last_template_error_tick = tinst_level_tick;
5046 error ("template instantiation depth exceeds maximum of %d (use "
5047 "-ftemplate-depth-NN to increase the maximum) instantiating %qD",
5048 max_tinst_depth, d);
5050 print_instantiation_context ();
5055 new = make_node (TINST_LEVEL);
5056 TINST_DECL (new) = d;
5057 TINST_LOCATION (new) = input_location;
5058 TINST_IN_SYSTEM_HEADER_P (new) = in_system_header;
5059 TREE_CHAIN (new) = current_tinst_level;
5060 current_tinst_level = new;
5063 #ifdef GATHER_STATISTICS
5064 if (tinst_depth > depth_reached)
5065 depth_reached = tinst_depth;
5072 /* We're done instantiating this template; return to the instantiation
5076 pop_tinst_level (void)
5078 tree old = current_tinst_level;
5080 /* Restore the filename and line number stashed away when we started
5081 this instantiation. */
5082 input_location = TINST_LOCATION (old);
5083 in_system_header = TINST_IN_SYSTEM_HEADER_P (old);
5084 current_tinst_level = TREE_CHAIN (old);
5089 /* We're instantiating a deferred template; restore the template
5090 instantiation context in which the instantiation was requested, which
5091 is one step out from LEVEL. */
5094 reopen_tinst_level (tree level)
5099 for (t = level; t; t = TREE_CHAIN (t))
5102 current_tinst_level = level;
5106 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the
5107 vector of template arguments, as for tsubst.
5109 Returns an appropriate tsubst'd friend declaration. */
5112 tsubst_friend_function (tree decl, tree args)
5116 if (TREE_CODE (decl) == FUNCTION_DECL
5117 && DECL_TEMPLATE_INSTANTIATION (decl)
5118 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
5119 /* This was a friend declared with an explicit template
5120 argument list, e.g.:
5124 to indicate that f was a template instantiation, not a new
5125 function declaration. Now, we have to figure out what
5126 instantiation of what template. */
5128 tree template_id, arglist, fns;
5131 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type));
5133 /* Friend functions are looked up in the containing namespace scope.
5134 We must enter that scope, to avoid finding member functions of the
5135 current cless with same name. */
5136 push_nested_namespace (ns);
5137 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args,
5138 tf_error | tf_warning, NULL_TREE);
5139 pop_nested_namespace (ns);
5140 arglist = tsubst (DECL_TI_ARGS (decl), args,
5141 tf_error | tf_warning, NULL_TREE);
5142 template_id = lookup_template_function (fns, arglist);
5144 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5145 tmpl = determine_specialization (template_id, new_friend,
5147 /*need_member_template=*/0,
5148 TREE_VEC_LENGTH (args));
5149 return instantiate_template (tmpl, new_args, tf_error);
5152 new_friend = tsubst (decl, args, tf_error | tf_warning, NULL_TREE);
5154 /* The NEW_FRIEND will look like an instantiation, to the
5155 compiler, but is not an instantiation from the point of view of
5156 the language. For example, we might have had:
5158 template <class T> struct S {
5159 template <class U> friend void f(T, U);
5162 Then, in S<int>, template <class U> void f(int, U) is not an
5163 instantiation of anything. */
5164 if (new_friend == error_mark_node)
5165 return error_mark_node;
5167 DECL_USE_TEMPLATE (new_friend) = 0;
5168 if (TREE_CODE (decl) == TEMPLATE_DECL)
5170 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0;
5171 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend))
5172 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl));
5175 /* The mangled name for the NEW_FRIEND is incorrect. The function
5176 is not a template instantiation and should not be mangled like
5177 one. Therefore, we forget the mangling here; we'll recompute it
5178 later if we need it. */
5179 if (TREE_CODE (new_friend) != TEMPLATE_DECL)
5181 SET_DECL_RTL (new_friend, NULL_RTX);
5182 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE);
5185 if (DECL_NAMESPACE_SCOPE_P (new_friend))
5188 tree new_friend_template_info;
5189 tree new_friend_result_template_info;
5191 int new_friend_is_defn;
5193 /* We must save some information from NEW_FRIEND before calling
5194 duplicate decls since that function will free NEW_FRIEND if
5196 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend);
5197 new_friend_is_defn =
5198 (DECL_INITIAL (DECL_TEMPLATE_RESULT
5199 (template_for_substitution (new_friend)))
5201 if (TREE_CODE (new_friend) == TEMPLATE_DECL)
5203 /* This declaration is a `primary' template. */
5204 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend;
5206 new_friend_result_template_info
5207 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend));
5210 new_friend_result_template_info = NULL_TREE;
5212 /* Inside pushdecl_namespace_level, we will push into the
5213 current namespace. However, the friend function should go
5214 into the namespace of the template. */
5215 ns = decl_namespace_context (new_friend);
5216 push_nested_namespace (ns);
5217 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true);
5218 pop_nested_namespace (ns);
5220 if (old_decl != new_friend)
5222 /* This new friend declaration matched an existing
5223 declaration. For example, given:
5225 template <class T> void f(T);
5226 template <class U> class C {
5227 template <class T> friend void f(T) {}
5230 the friend declaration actually provides the definition
5231 of `f', once C has been instantiated for some type. So,
5232 old_decl will be the out-of-class template declaration,
5233 while new_friend is the in-class definition.
5235 But, if `f' was called before this point, the
5236 instantiation of `f' will have DECL_TI_ARGS corresponding
5237 to `T' but not to `U', references to which might appear
5238 in the definition of `f'. Previously, the most general
5239 template for an instantiation of `f' was the out-of-class
5240 version; now it is the in-class version. Therefore, we
5241 run through all specialization of `f', adding to their
5242 DECL_TI_ARGS appropriately. In particular, they need a
5243 new set of outer arguments, corresponding to the
5244 arguments for this class instantiation.
5246 The same situation can arise with something like this:
5249 template <class T> class C {
5253 when `C<int>' is instantiated. Now, `f(int)' is defined
5256 if (!new_friend_is_defn)
5257 /* On the other hand, if the in-class declaration does
5258 *not* provide a definition, then we don't want to alter
5259 existing definitions. We can just leave everything
5264 /* Overwrite whatever template info was there before, if
5265 any, with the new template information pertaining to
5267 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info;
5269 if (TREE_CODE (old_decl) != TEMPLATE_DECL)
5270 reregister_specialization (new_friend,
5271 most_general_template (old_decl),
5276 tree new_friend_args;
5278 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl))
5279 = new_friend_result_template_info;
5281 new_friend_args = TI_ARGS (new_friend_template_info);
5282 for (t = DECL_TEMPLATE_SPECIALIZATIONS (old_decl);
5286 tree spec = TREE_VALUE (t);
5289 = add_outermost_template_args (new_friend_args,
5290 DECL_TI_ARGS (spec));
5293 /* Now, since specializations are always supposed to
5294 hang off of the most general template, we must move
5296 t = most_general_template (old_decl);
5299 DECL_TEMPLATE_SPECIALIZATIONS (t)
5300 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (t),
5301 DECL_TEMPLATE_SPECIALIZATIONS (old_decl));
5302 DECL_TEMPLATE_SPECIALIZATIONS (old_decl) = NULL_TREE;
5307 /* The information from NEW_FRIEND has been merged into OLD_DECL
5308 by duplicate_decls. */
5309 new_friend = old_decl;
5314 tree context = DECL_CONTEXT (new_friend);
5318 template <class T> class C {
5319 template <class U> friend void C1<U>::f (); // case 1
5320 friend void C2<T>::f (); // case 2
5322 we only need to make sure CONTEXT is a complete type for
5323 case 2. To distinguish between the two cases, we note that
5324 CONTEXT of case 1 remains dependent type after tsubst while
5325 this isn't true for case 2. */
5326 ++processing_template_decl;
5327 dependent_p = dependent_type_p (context);
5328 --processing_template_decl;
5331 && !complete_type_or_else (context, NULL_TREE))
5332 return error_mark_node;
5334 if (COMPLETE_TYPE_P (context))
5336 /* Check to see that the declaration is really present, and,
5337 possibly obtain an improved declaration. */
5338 tree fn = check_classfn (context,
5339 new_friend, NULL_TREE);
5349 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of
5350 template arguments, as for tsubst.
5352 Returns an appropriate tsubst'd friend type or error_mark_node on
5356 tsubst_friend_class (tree friend_tmpl, tree args)
5362 context = DECL_CONTEXT (friend_tmpl);
5366 if (TREE_CODE (context) == NAMESPACE_DECL)
5367 push_nested_namespace (context);
5369 push_nested_class (tsubst (context, args, tf_none, NULL_TREE));
5372 /* First, we look for a class template. */
5373 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/0);
5375 /* But, if we don't find one, it might be because we're in a
5376 situation like this:
5384 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL
5385 for `S<int>', not the TEMPLATE_DECL. */
5386 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl))
5388 tmpl = lookup_name (DECL_NAME (friend_tmpl), /*prefer_type=*/1);
5389 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
5392 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl))
5394 /* The friend template has already been declared. Just
5395 check to see that the declarations match, and install any new
5396 default parameters. We must tsubst the default parameters,
5397 of course. We only need the innermost template parameters
5398 because that is all that redeclare_class_template will look
5400 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl))
5401 > TMPL_ARGS_DEPTH (args))
5404 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl),
5405 args, tf_error | tf_warning);
5406 redeclare_class_template (TREE_TYPE (tmpl), parms);
5409 friend_type = TREE_TYPE (tmpl);
5413 /* The friend template has not already been declared. In this
5414 case, the instantiation of the template class will cause the
5415 injection of this template into the global scope. */
5416 tmpl = tsubst (friend_tmpl, args, tf_error | tf_warning, NULL_TREE);
5418 /* The new TMPL is not an instantiation of anything, so we
5419 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for
5420 the new type because that is supposed to be the corresponding
5421 template decl, i.e., TMPL. */
5422 DECL_USE_TEMPLATE (tmpl) = 0;
5423 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE;
5424 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0;
5425 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))
5426 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)));
5428 /* Inject this template into the global scope. */
5429 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true));
5434 if (TREE_CODE (context) == NAMESPACE_DECL)
5435 pop_nested_namespace (context);
5437 pop_nested_class ();
5443 /* Returns zero if TYPE cannot be completed later due to circularity.
5444 Otherwise returns one. */
5447 can_complete_type_without_circularity (tree type)
5449 if (type == NULL_TREE || type == error_mark_node)
5451 else if (COMPLETE_TYPE_P (type))
5453 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
5454 return can_complete_type_without_circularity (TREE_TYPE (type));
5455 else if (CLASS_TYPE_P (type)
5456 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type)))
5463 instantiate_class_template (tree type)
5465 tree template, args, pattern, t, member;
5470 if (type == error_mark_node)
5471 return error_mark_node;
5473 if (TYPE_BEING_DEFINED (type)
5474 || COMPLETE_TYPE_P (type)
5475 || dependent_type_p (type))
5478 /* Figure out which template is being instantiated. */
5479 template = most_general_template (CLASSTYPE_TI_TEMPLATE (type));
5480 gcc_assert (TREE_CODE (template) == TEMPLATE_DECL);
5482 /* Figure out which arguments are being used to do the
5484 args = CLASSTYPE_TI_ARGS (type);
5486 /* Determine what specialization of the original template to
5488 t = most_specialized_class (template, args);
5489 if (t == error_mark_node)
5491 const char *str = "candidates are:";
5492 error ("ambiguous class template instantiation for %q#T", type);
5493 for (t = DECL_TEMPLATE_SPECIALIZATIONS (template); t;
5496 if (get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args))
5498 error ("%s %+#T", str, TREE_TYPE (t));
5502 TYPE_BEING_DEFINED (type) = 1;
5503 return error_mark_node;
5507 pattern = TREE_TYPE (t);
5509 pattern = TREE_TYPE (template);
5511 /* If the template we're instantiating is incomplete, then clearly
5512 there's nothing we can do. */
5513 if (!COMPLETE_TYPE_P (pattern))
5516 /* If we've recursively instantiated too many templates, stop. */
5517 if (! push_tinst_level (type))
5520 /* Now we're really doing the instantiation. Mark the type as in
5521 the process of being defined. */
5522 TYPE_BEING_DEFINED (type) = 1;
5524 /* We may be in the middle of deferred access check. Disable
5526 push_deferring_access_checks (dk_no_deferred);
5528 push_to_top_level ();
5532 /* This TYPE is actually an instantiation of a partial
5533 specialization. We replace the innermost set of ARGS with
5534 the arguments appropriate for substitution. For example,
5537 template <class T> struct S {};
5538 template <class T> struct S<T*> {};
5540 and supposing that we are instantiating S<int*>, ARGS will
5541 present be {int*} but we need {int}. */
5543 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t),
5546 /* If there were multiple levels in ARGS, replacing the
5547 innermost level would alter CLASSTYPE_TI_ARGS, which we don't
5548 want, so we make a copy first. */
5549 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args))
5551 args = copy_node (args);
5552 SET_TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args), inner_args);
5558 SET_CLASSTYPE_INTERFACE_UNKNOWN (type);
5560 /* Set the input location to the template definition. This is needed
5561 if tsubsting causes an error. */
5562 typedecl = TYPE_MAIN_DECL (type);
5563 input_location = DECL_SOURCE_LOCATION (typedecl);
5564 in_system_header = DECL_IN_SYSTEM_HEADER (typedecl);
5566 TYPE_HAS_CONSTRUCTOR (type) = TYPE_HAS_CONSTRUCTOR (pattern);
5567 TYPE_HAS_NEW_OPERATOR (type) = TYPE_HAS_NEW_OPERATOR (pattern);
5568 TYPE_HAS_ARRAY_NEW_OPERATOR (type) = TYPE_HAS_ARRAY_NEW_OPERATOR (pattern);
5569 TYPE_GETS_DELETE (type) = TYPE_GETS_DELETE (pattern);
5570 TYPE_HAS_ASSIGN_REF (type) = TYPE_HAS_ASSIGN_REF (pattern);
5571 TYPE_HAS_CONST_ASSIGN_REF (type) = TYPE_HAS_CONST_ASSIGN_REF (pattern);
5572 TYPE_HAS_INIT_REF (type) = TYPE_HAS_INIT_REF (pattern);
5573 TYPE_HAS_CONST_INIT_REF (type) = TYPE_HAS_CONST_INIT_REF (pattern);
5574 TYPE_HAS_DEFAULT_CONSTRUCTOR (type) = TYPE_HAS_DEFAULT_CONSTRUCTOR (pattern);
5575 TYPE_HAS_CONVERSION (type) = TYPE_HAS_CONVERSION (pattern);
5576 TYPE_PACKED (type) = TYPE_PACKED (pattern);
5577 TYPE_ALIGN (type) = TYPE_ALIGN (pattern);
5578 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern);
5579 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */
5580 if (ANON_AGGR_TYPE_P (pattern))
5581 SET_ANON_AGGR_TYPE_P (type);
5582 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern))
5584 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1;
5585 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern);
5588 pbinfo = TYPE_BINFO (pattern);
5590 /* We should never instantiate a nested class before its enclosing
5591 class; we need to look up the nested class by name before we can
5592 instantiate it, and that lookup should instantiate the enclosing
5594 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern))
5595 || COMPLETE_TYPE_P (TYPE_CONTEXT (type))
5596 || TYPE_BEING_DEFINED (TYPE_CONTEXT (type)));
5598 base_list = NULL_TREE;
5599 if (BINFO_N_BASE_BINFOS (pbinfo))
5602 tree context = TYPE_CONTEXT (type);
5606 /* We must enter the scope containing the type, as that is where
5607 the accessibility of types named in dependent bases are
5609 pushed_scope = push_scope (context ? context : global_namespace);
5611 /* Substitute into each of the bases to determine the actual
5613 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++)
5616 tree access = BINFO_BASE_ACCESS (pbinfo, i);
5618 /* Substitute to figure out the base class. */
5619 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, NULL_TREE);
5620 if (base == error_mark_node)
5623 base_list = tree_cons (access, base, base_list);
5624 if (BINFO_VIRTUAL_P (pbase_binfo))
5625 TREE_TYPE (base_list) = integer_type_node;
5628 /* The list is now in reverse order; correct that. */
5629 base_list = nreverse (base_list);
5632 pop_scope (pushed_scope);
5634 /* Now call xref_basetypes to set up all the base-class
5636 xref_basetypes (type, base_list);
5639 /* Now that our base classes are set up, enter the scope of the
5640 class, so that name lookups into base classes, etc. will work
5641 correctly. This is precisely analogous to what we do in
5642 begin_class_definition when defining an ordinary non-template
5646 /* Now members are processed in the order of declaration. */
5647 for (member = CLASSTYPE_DECL_LIST (pattern);
5648 member; member = TREE_CHAIN (member))
5650 tree t = TREE_VALUE (member);
5652 if (TREE_PURPOSE (member))
5656 /* Build new CLASSTYPE_NESTED_UTDS. */
5659 tree name = TYPE_IDENTIFIER (tag);
5661 bool class_template_p;
5663 class_template_p = (TREE_CODE (tag) != ENUMERAL_TYPE
5664 && TYPE_LANG_SPECIFIC (tag)
5665 && CLASSTYPE_IS_TEMPLATE (tag));
5666 /* If the member is a class template, then -- even after
5667 substitution -- there may be dependent types in the
5668 template argument list for the class. We increment
5669 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as
5670 that function will assume that no types are dependent
5671 when outside of a template. */
5672 if (class_template_p)
5673 ++processing_template_decl;
5674 newtag = tsubst (tag, args, tf_error, NULL_TREE);
5675 if (class_template_p)
5676 --processing_template_decl;
5677 if (newtag == error_mark_node)
5680 if (TREE_CODE (newtag) != ENUMERAL_TYPE)
5682 if (class_template_p)
5683 /* Unfortunately, lookup_template_class sets
5684 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial
5685 instantiation (i.e., for the type of a member
5686 template class nested within a template class.)
5687 This behavior is required for
5688 maybe_process_partial_specialization to work
5689 correctly, but is not accurate in this case;
5690 the TAG is not an instantiation of anything.
5691 (The corresponding TEMPLATE_DECL is an
5692 instantiation, but the TYPE is not.) */
5693 CLASSTYPE_USE_TEMPLATE (newtag) = 0;
5695 /* Now, we call pushtag to put this NEWTAG into the scope of
5696 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid
5697 pushtag calling push_template_decl. We don't have to do
5698 this for enums because it will already have been done in
5701 SET_IDENTIFIER_TYPE_VALUE (name, newtag);
5702 pushtag (name, newtag, /*tag_scope=*/ts_current);
5705 else if (TREE_CODE (t) == FUNCTION_DECL
5706 || DECL_FUNCTION_TEMPLATE_P (t))
5708 /* Build new TYPE_METHODS. */
5711 if (TREE_CODE (t) == TEMPLATE_DECL)
5712 ++processing_template_decl;
5713 r = tsubst (t, args, tf_error, NULL_TREE);
5714 if (TREE_CODE (t) == TEMPLATE_DECL)
5715 --processing_template_decl;
5716 set_current_access_from_decl (r);
5717 grok_special_member_properties (r);
5718 finish_member_declaration (r);
5722 /* Build new TYPE_FIELDS. */
5724 if (TREE_CODE (t) != CONST_DECL)
5728 /* The the file and line for this declaration, to
5729 assist in error message reporting. Since we
5730 called push_tinst_level above, we don't need to
5732 input_location = DECL_SOURCE_LOCATION (t);
5734 if (TREE_CODE (t) == TEMPLATE_DECL)
5735 ++processing_template_decl;
5736 r = tsubst (t, args, tf_error | tf_warning, NULL_TREE);
5737 if (TREE_CODE (t) == TEMPLATE_DECL)
5738 --processing_template_decl;
5739 if (TREE_CODE (r) == VAR_DECL)
5743 [t]he initialization (and any associated
5744 side-effects) of a static data member does
5745 not occur unless the static data member is
5746 itself used in a way that requires the
5747 definition of the static data member to
5750 Therefore, we do not substitute into the
5751 initialized for the static data member here. */
5752 finish_static_data_member_decl
5755 /*asmspec_tree=*/NULL_TREE,
5757 if (DECL_INITIALIZED_IN_CLASS_P (r))
5758 check_static_variable_definition (r, TREE_TYPE (r));
5760 else if (TREE_CODE (r) == FIELD_DECL)
5762 /* Determine whether R has a valid type and can be
5763 completed later. If R is invalid, then it is
5764 replaced by error_mark_node so that it will not be
5765 added to TYPE_FIELDS. */
5766 tree rtype = TREE_TYPE (r);
5767 if (can_complete_type_without_circularity (rtype))
5768 complete_type (rtype);
5770 if (!COMPLETE_TYPE_P (rtype))
5772 cxx_incomplete_type_error (r, rtype);
5773 r = error_mark_node;
5777 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE,
5778 such a thing will already have been added to the field
5779 list by tsubst_enum in finish_member_declaration in the
5780 CLASSTYPE_NESTED_UTDS case above. */
5781 if (!(TREE_CODE (r) == TYPE_DECL
5782 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE
5783 && DECL_ARTIFICIAL (r)))
5785 set_current_access_from_decl (r);
5786 finish_member_declaration (r);
5793 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t))
5795 /* Build new CLASSTYPE_FRIEND_CLASSES. */
5797 tree friend_type = t;
5798 bool adjust_processing_template_decl = false;
5800 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5802 /* template <class T> friend class C; */
5803 friend_type = tsubst_friend_class (friend_type, args);
5804 adjust_processing_template_decl = true;
5806 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE)
5808 /* template <class T> friend class C::D; */
5809 friend_type = tsubst (friend_type, args,
5810 tf_error | tf_warning, NULL_TREE);
5811 if (TREE_CODE (friend_type) == TEMPLATE_DECL)
5812 friend_type = TREE_TYPE (friend_type);
5813 adjust_processing_template_decl = true;
5815 else if (TREE_CODE (friend_type) == TYPENAME_TYPE)
5817 /* This could be either
5821 when dependent_type_p is false or
5823 template <class U> friend class T::C;
5826 friend_type = tsubst (friend_type, args,
5827 tf_error | tf_warning, NULL_TREE);
5828 /* Bump processing_template_decl for correct
5829 dependent_type_p calculation. */
5830 ++processing_template_decl;
5831 if (dependent_type_p (friend_type))
5832 adjust_processing_template_decl = true;
5833 --processing_template_decl;
5835 else if (!CLASSTYPE_USE_TEMPLATE (friend_type)
5836 && hidden_name_p (TYPE_NAME (friend_type)))
5840 where C hasn't been declared yet. Let's lookup name
5841 from namespace scope directly, bypassing any name that
5842 come from dependent base class. */
5843 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type));
5845 /* The call to xref_tag_from_type does injection for friend
5847 push_nested_namespace (ns);
5849 xref_tag_from_type (friend_type, NULL_TREE,
5850 /*tag_scope=*/ts_current);
5851 pop_nested_namespace (ns);
5853 else if (uses_template_parms (friend_type))
5854 /* friend class C<T>; */
5855 friend_type = tsubst (friend_type, args,
5856 tf_error | tf_warning, NULL_TREE);
5861 where C is already declared or
5863 friend class C<int>;
5865 We don't have to do anything in these cases. */
5867 if (adjust_processing_template_decl)
5868 /* Trick make_friend_class into realizing that the friend
5869 we're adding is a template, not an ordinary class. It's
5870 important that we use make_friend_class since it will
5871 perform some error-checking and output cross-reference
5873 ++processing_template_decl;
5875 if (friend_type != error_mark_node)
5876 make_friend_class (type, friend_type, /*complain=*/false);
5878 if (adjust_processing_template_decl)
5879 --processing_template_decl;
5883 /* Build new DECL_FRIENDLIST. */
5886 /* The the file and line for this declaration, to
5887 assist in error message reporting. Since we
5888 called push_tinst_level above, we don't need to
5890 input_location = DECL_SOURCE_LOCATION (t);
5892 if (TREE_CODE (t) == TEMPLATE_DECL)
5894 ++processing_template_decl;
5895 push_deferring_access_checks (dk_no_check);
5898 r = tsubst_friend_function (t, args);
5899 add_friend (type, r, /*complain=*/false);
5900 if (TREE_CODE (t) == TEMPLATE_DECL)
5902 pop_deferring_access_checks ();
5903 --processing_template_decl;
5909 /* Set the file and line number information to whatever is given for
5910 the class itself. This puts error messages involving generated
5911 implicit functions at a predictable point, and the same point
5912 that would be used for non-template classes. */
5913 input_location = DECL_SOURCE_LOCATION (typedecl);
5915 unreverse_member_declarations (type);
5916 finish_struct_1 (type);
5917 TYPE_BEING_DEFINED (type) = 0;
5919 /* Now that the class is complete, instantiate default arguments for
5920 any member functions. We don't do this earlier because the
5921 default arguments may reference members of the class. */
5922 if (!PRIMARY_TEMPLATE_P (template))
5923 for (t = TYPE_METHODS (type); t; t = TREE_CHAIN (t))
5924 if (TREE_CODE (t) == FUNCTION_DECL
5925 /* Implicitly generated member functions will not have template
5926 information; they are not instantiations, but instead are
5927 created "fresh" for each instantiation. */
5928 && DECL_TEMPLATE_INFO (t))
5929 tsubst_default_arguments (t);
5932 pop_from_top_level ();
5933 pop_deferring_access_checks ();
5936 /* The vtable for a template class can be emitted in any translation
5937 unit in which the class is instantiated. When there is no key
5938 method, however, finish_struct_1 will already have added TYPE to
5939 the keyed_classes list. */
5940 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type))
5941 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes);
5947 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5953 else if (TYPE_P (t))
5954 r = tsubst (t, args, complain, in_decl);
5957 r = tsubst_expr (t, args, complain, in_decl);
5958 r = fold_non_dependent_expr (r);
5963 /* Substitute ARGS into the vector or list of template arguments T. */
5966 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl)
5968 int len = TREE_VEC_LENGTH (t);
5969 int need_new = 0, i;
5970 tree *elts = alloca (len * sizeof (tree));
5972 for (i = 0; i < len; i++)
5974 tree orig_arg = TREE_VEC_ELT (t, i);
5977 if (TREE_CODE (orig_arg) == TREE_VEC)
5978 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl);
5980 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl);
5982 if (new_arg == error_mark_node)
5983 return error_mark_node;
5986 if (new_arg != orig_arg)
5993 t = make_tree_vec (len);
5994 for (i = 0; i < len; i++)
5995 TREE_VEC_ELT (t, i) = elts[i];
6000 /* Return the result of substituting ARGS into the template parameters
6001 given by PARMS. If there are m levels of ARGS and m + n levels of
6002 PARMS, then the result will contain n levels of PARMS. For
6003 example, if PARMS is `template <class T> template <class U>
6004 template <T*, U, class V>' and ARGS is {{int}, {double}} then the
6005 result will be `template <int*, double, class V>'. */
6008 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain)
6013 /* When substituting into a template, we must set
6014 PROCESSING_TEMPLATE_DECL as the template parameters may be
6015 dependent if they are based on one-another, and the dependency
6016 predicates are short-circuit outside of templates. */
6017 ++processing_template_decl;
6019 for (new_parms = &r;
6020 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args);
6021 new_parms = &(TREE_CHAIN (*new_parms)),
6022 parms = TREE_CHAIN (parms))
6025 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms)));
6028 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i)
6030 tree tuple = TREE_VEC_ELT (TREE_VALUE (parms), i);
6031 tree default_value = TREE_PURPOSE (tuple);
6032 tree parm_decl = TREE_VALUE (tuple);
6034 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE);
6035 if (TREE_CODE (parm_decl) == PARM_DECL
6036 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain))
6037 parm_decl = error_mark_node;
6038 default_value = tsubst_template_arg (default_value, args,
6039 complain, NULL_TREE);
6041 tuple = build_tree_list (default_value, parm_decl);
6042 TREE_VEC_ELT (new_vec, i) = tuple;
6046 tree_cons (size_int (TMPL_PARMS_DEPTH (parms)
6047 - TMPL_ARGS_DEPTH (args)),
6048 new_vec, NULL_TREE);
6051 --processing_template_decl;
6056 /* Substitute the ARGS into the indicated aggregate (or enumeration)
6057 type T. If T is not an aggregate or enumeration type, it is
6058 handled as if by tsubst. IN_DECL is as for tsubst. If
6059 ENTERING_SCOPE is nonzero, T is the context for a template which
6060 we are presently tsubst'ing. Return the substituted value. */
6063 tsubst_aggr_type (tree t,
6065 tsubst_flags_t complain,
6072 switch (TREE_CODE (t))
6075 if (TYPE_PTRMEMFUNC_P (t))
6076 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl);
6078 /* Else fall through. */
6081 if (TYPE_TEMPLATE_INFO (t))
6086 bool saved_skip_evaluation;
6088 /* In "sizeof(X<I>)" we need to evaluate "I". */
6089 saved_skip_evaluation = skip_evaluation;
6090 skip_evaluation = false;
6092 /* First, determine the context for the type we are looking
6094 context = TYPE_CONTEXT (t);
6096 context = tsubst_aggr_type (context, args, complain,
6097 in_decl, /*entering_scope=*/1);
6099 /* Then, figure out what arguments are appropriate for the
6100 type we are trying to find. For example, given:
6102 template <class T> struct S;
6103 template <class T, class U> void f(T, U) { S<U> su; }
6105 and supposing that we are instantiating f<int, double>,
6106 then our ARGS will be {int, double}, but, when looking up
6107 S we only want {double}. */
6108 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args,
6110 if (argvec == error_mark_node)
6111 r = error_mark_node;
6114 r = lookup_template_class (t, argvec, in_decl, context,
6115 entering_scope, complain);
6116 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
6119 skip_evaluation = saved_skip_evaluation;
6124 /* This is not a template type, so there's nothing to do. */
6128 return tsubst (t, args, complain, in_decl);
6132 /* Substitute into the default argument ARG (a default argument for
6133 FN), which has the indicated TYPE. */
6136 tsubst_default_argument (tree fn, tree type, tree arg)
6138 tree saved_class_ptr = NULL_TREE;
6139 tree saved_class_ref = NULL_TREE;
6141 /* This default argument came from a template. Instantiate the
6142 default argument here, not in tsubst. In the case of
6151 we must be careful to do name lookup in the scope of S<T>,
6152 rather than in the current class. */
6153 push_access_scope (fn);
6154 /* The "this" pointer is not valid in a default argument. */
6157 saved_class_ptr = current_class_ptr;
6158 cp_function_chain->x_current_class_ptr = NULL_TREE;
6159 saved_class_ref = current_class_ref;
6160 cp_function_chain->x_current_class_ref = NULL_TREE;
6163 push_deferring_access_checks(dk_no_deferred);
6164 arg = tsubst_expr (arg, DECL_TI_ARGS (fn),
6165 tf_error | tf_warning, NULL_TREE);
6166 pop_deferring_access_checks();
6168 /* Restore the "this" pointer. */
6171 cp_function_chain->x_current_class_ptr = saved_class_ptr;
6172 cp_function_chain->x_current_class_ref = saved_class_ref;
6175 pop_access_scope (fn);
6177 /* Make sure the default argument is reasonable. */
6178 arg = check_default_argument (type, arg);
6183 /* Substitute into all the default arguments for FN. */
6186 tsubst_default_arguments (tree fn)
6191 tmpl_args = DECL_TI_ARGS (fn);
6193 /* If this function is not yet instantiated, we certainly don't need
6194 its default arguments. */
6195 if (uses_template_parms (tmpl_args))
6198 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn));
6200 arg = TREE_CHAIN (arg))
6201 if (TREE_PURPOSE (arg))
6202 TREE_PURPOSE (arg) = tsubst_default_argument (fn,
6204 TREE_PURPOSE (arg));
6207 /* Substitute the ARGS into the T, which is a _DECL. Return the
6208 result of the substitution. Issue error and warning messages under
6209 control of COMPLAIN. */
6212 tsubst_decl (tree t, tree args, tsubst_flags_t complain)
6214 location_t saved_loc;
6218 /* Set the filename and linenumber to improve error-reporting. */
6219 saved_loc = input_location;
6220 input_location = DECL_SOURCE_LOCATION (t);
6222 switch (TREE_CODE (t))
6226 /* We can get here when processing a member function template,
6227 member class template, and template template parameter of
6228 a template class. */
6229 tree decl = DECL_TEMPLATE_RESULT (t);
6234 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
6236 /* Template template parameter is treated here. */
6237 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6238 if (new_type == error_mark_node)
6239 return error_mark_node;
6242 TREE_CHAIN (r) = NULL_TREE;
6243 TREE_TYPE (r) = new_type;
6244 DECL_TEMPLATE_RESULT (r)
6245 = build_decl (TYPE_DECL, DECL_NAME (decl), new_type);
6246 DECL_TEMPLATE_PARMS (r)
6247 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6249 TYPE_NAME (new_type) = r;
6253 /* We might already have an instance of this template.
6254 The ARGS are for the surrounding class type, so the
6255 full args contain the tsubst'd args for the context,
6256 plus the innermost args from the template decl. */
6257 tmpl_args = DECL_CLASS_TEMPLATE_P (t)
6258 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t))
6259 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t));
6260 /* Because this is a template, the arguments will still be
6261 dependent, even after substitution. If
6262 PROCESSING_TEMPLATE_DECL is not set, the dependency
6263 predicates will short-circuit. */
6264 ++processing_template_decl;
6265 full_args = tsubst_template_args (tmpl_args, args,
6267 --processing_template_decl;
6268 if (full_args == error_mark_node)
6269 return error_mark_node;
6271 /* tsubst_template_args doesn't copy the vector if
6272 nothing changed. But, *something* should have
6274 gcc_assert (full_args != tmpl_args);
6276 spec = retrieve_specialization (t, full_args,
6277 /*class_specializations_p=*/true);
6278 if (spec != NULL_TREE)
6284 /* Make a new template decl. It will be similar to the
6285 original, but will record the current template arguments.
6286 We also create a new function declaration, which is just
6287 like the old one, but points to this new template, rather
6288 than the old one. */
6290 gcc_assert (DECL_LANG_SPECIFIC (r) != 0);
6291 TREE_CHAIN (r) = NULL_TREE;
6293 DECL_TEMPLATE_INFO (r) = build_tree_list (t, args);
6295 if (TREE_CODE (decl) == TYPE_DECL)
6298 ++processing_template_decl;
6299 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6300 --processing_template_decl;
6301 if (new_type == error_mark_node)
6302 return error_mark_node;
6304 TREE_TYPE (r) = new_type;
6305 CLASSTYPE_TI_TEMPLATE (new_type) = r;
6306 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type);
6307 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type);
6308 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type);
6313 ++processing_template_decl;
6314 new_decl = tsubst (decl, args, complain, in_decl);
6315 --processing_template_decl;
6316 if (new_decl == error_mark_node)
6317 return error_mark_node;
6319 DECL_TEMPLATE_RESULT (r) = new_decl;
6320 DECL_TI_TEMPLATE (new_decl) = r;
6321 TREE_TYPE (r) = TREE_TYPE (new_decl);
6322 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl);
6323 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl);
6326 SET_DECL_IMPLICIT_INSTANTIATION (r);
6327 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE;
6328 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE;
6330 /* The template parameters for this new template are all the
6331 template parameters for the old template, except the
6332 outermost level of parameters. */
6333 DECL_TEMPLATE_PARMS (r)
6334 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args,
6337 if (PRIMARY_TEMPLATE_P (t))
6338 DECL_PRIMARY_TEMPLATE (r) = r;
6340 if (TREE_CODE (decl) != TYPE_DECL)
6341 /* Record this non-type partial instantiation. */
6342 register_specialization (r, t,
6343 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)),
6351 tree argvec = NULL_TREE;
6359 /* Nobody should be tsubst'ing into non-template functions. */
6360 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE);
6362 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL)
6367 /* If T is not dependent, just return it. We have to
6368 increment PROCESSING_TEMPLATE_DECL because
6369 value_dependent_expression_p assumes that nothing is
6370 dependent when PROCESSING_TEMPLATE_DECL is zero. */
6371 ++processing_template_decl;
6372 dependent_p = value_dependent_expression_p (t);
6373 --processing_template_decl;
6377 /* Calculate the most general template of which R is a
6378 specialization, and the complete set of arguments used to
6380 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t));
6381 argvec = tsubst_template_args (DECL_TI_ARGS
6382 (DECL_TEMPLATE_RESULT (gen_tmpl)),
6383 args, complain, in_decl);
6385 /* Check to see if we already have this specialization. */
6386 spec = retrieve_specialization (gen_tmpl, argvec,
6387 /*class_specializations_p=*/false);
6395 /* We can see more levels of arguments than parameters if
6396 there was a specialization of a member template, like
6399 template <class T> struct S { template <class U> void f(); }
6400 template <> template <class U> void S<int>::f(U);
6402 Here, we'll be substituting into the specialization,
6403 because that's where we can find the code we actually
6404 want to generate, but we'll have enough arguments for
6405 the most general template.
6407 We also deal with the peculiar case:
6409 template <class T> struct S {
6410 template <class U> friend void f();
6412 template <class U> void f() {}
6414 template void f<double>();
6416 Here, the ARGS for the instantiation of will be {int,
6417 double}. But, we only need as many ARGS as there are
6418 levels of template parameters in CODE_PATTERN. We are
6419 careful not to get fooled into reducing the ARGS in
6422 template <class T> struct S { template <class U> void f(U); }
6423 template <class T> template <> void S<T>::f(int) {}
6425 which we can spot because the pattern will be a
6426 specialization in this case. */
6427 args_depth = TMPL_ARGS_DEPTH (args);
6429 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t)));
6430 if (args_depth > parms_depth
6431 && !DECL_TEMPLATE_SPECIALIZATION (t))
6432 args = get_innermost_template_args (args, parms_depth);
6436 /* This special case arises when we have something like this:
6438 template <class T> struct S {
6439 friend void f<int>(int, double);
6442 Here, the DECL_TI_TEMPLATE for the friend declaration
6443 will be an IDENTIFIER_NODE. We are being called from
6444 tsubst_friend_function, and we want only to create a
6445 new decl (R) with appropriate types so that we can call
6446 determine_specialization. */
6447 gen_tmpl = NULL_TREE;
6450 if (DECL_CLASS_SCOPE_P (t))
6452 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t)))
6456 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6457 complain, t, /*entering_scope=*/1);
6462 ctx = DECL_CONTEXT (t);
6464 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6465 if (type == error_mark_node)
6466 return error_mark_node;
6468 /* We do NOT check for matching decls pushed separately at this
6469 point, as they may not represent instantiations of this
6470 template, and in any case are considered separate under the
6473 DECL_USE_TEMPLATE (r) = 0;
6474 TREE_TYPE (r) = type;
6475 /* Clear out the mangled name and RTL for the instantiation. */
6476 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6477 SET_DECL_RTL (r, NULL_RTX);
6478 DECL_INITIAL (r) = NULL_TREE;
6479 DECL_CONTEXT (r) = ctx;
6481 if (member && DECL_CONV_FN_P (r))
6482 /* Type-conversion operator. Reconstruct the name, in
6483 case it's the name of one of the template's parameters. */
6484 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type));
6486 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args,
6488 DECL_RESULT (r) = NULL_TREE;
6490 TREE_STATIC (r) = 0;
6491 TREE_PUBLIC (r) = TREE_PUBLIC (t);
6492 DECL_EXTERNAL (r) = 1;
6493 /* If this is an instantiation of a function with internal
6494 linkage, we already know what object file linkage will be
6495 assigned to the instantiation. */
6496 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r);
6497 DECL_DEFER_OUTPUT (r) = 0;
6498 TREE_CHAIN (r) = NULL_TREE;
6499 DECL_PENDING_INLINE_INFO (r) = 0;
6500 DECL_PENDING_INLINE_P (r) = 0;
6501 DECL_SAVED_TREE (r) = NULL_TREE;
6503 if (DECL_CLONED_FUNCTION (r))
6505 DECL_CLONED_FUNCTION (r) = tsubst (DECL_CLONED_FUNCTION (t),
6507 TREE_CHAIN (r) = TREE_CHAIN (DECL_CLONED_FUNCTION (r));
6508 TREE_CHAIN (DECL_CLONED_FUNCTION (r)) = r;
6511 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do
6512 this in the special friend case mentioned above where
6513 GEN_TMPL is NULL. */
6516 DECL_TEMPLATE_INFO (r)
6517 = tree_cons (gen_tmpl, argvec, NULL_TREE);
6518 SET_DECL_IMPLICIT_INSTANTIATION (r);
6519 register_specialization (r, gen_tmpl, argvec, false);
6521 /* We're not supposed to instantiate default arguments
6522 until they are called, for a template. But, for a
6525 template <class T> void f ()
6526 { extern void g(int i = T()); }
6528 we should do the substitution when the template is
6529 instantiated. We handle the member function case in
6530 instantiate_class_template since the default arguments
6531 might refer to other members of the class. */
6533 && !PRIMARY_TEMPLATE_P (gen_tmpl)
6534 && !uses_template_parms (argvec))
6535 tsubst_default_arguments (r);
6538 DECL_TEMPLATE_INFO (r) = NULL_TREE;
6540 /* Copy the list of befriending classes. */
6541 for (friends = &DECL_BEFRIENDING_CLASSES (r);
6543 friends = &TREE_CHAIN (*friends))
6545 *friends = copy_node (*friends);
6546 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends),
6551 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r))
6553 maybe_retrofit_in_chrg (r);
6554 if (DECL_CONSTRUCTOR_P (r))
6555 grok_ctor_properties (ctx, r);
6556 /* If this is an instantiation of a member template, clone it.
6557 If it isn't, that'll be handled by
6558 clone_constructors_and_destructors. */
6559 if (PRIMARY_TEMPLATE_P (gen_tmpl))
6560 clone_function_decl (r, /*update_method_vec_p=*/0);
6562 else if (IDENTIFIER_OPNAME_P (DECL_NAME (r)))
6563 grok_op_properties (r, (complain & tf_error) != 0);
6565 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t))
6566 SET_DECL_FRIEND_CONTEXT (r,
6567 tsubst (DECL_FRIEND_CONTEXT (t),
6568 args, complain, in_decl));
6577 if (DECL_TEMPLATE_PARM_P (t))
6578 SET_DECL_TEMPLATE_PARM_P (r);
6580 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6581 type = type_decays_to (type);
6582 TREE_TYPE (r) = type;
6583 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6585 if (DECL_INITIAL (r))
6587 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX)
6588 DECL_INITIAL (r) = TREE_TYPE (r);
6590 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args,
6594 DECL_CONTEXT (r) = NULL_TREE;
6596 if (!DECL_TEMPLATE_PARM_P (r))
6597 DECL_ARG_TYPE (r) = type_passed_as (type);
6599 TREE_CHAIN (r) = tsubst (TREE_CHAIN (t), args,
6600 complain, TREE_CHAIN (t));
6609 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6610 if (type == error_mark_node)
6611 return error_mark_node;
6612 TREE_TYPE (r) = type;
6613 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6615 /* We don't have to set DECL_CONTEXT here; it is set by
6616 finish_member_declaration. */
6617 DECL_INITIAL (r) = tsubst_expr (DECL_INITIAL (t), args,
6619 TREE_CHAIN (r) = NULL_TREE;
6620 if (VOID_TYPE_P (type))
6621 error ("instantiation of %q+D as type %qT", r, type);
6626 /* We reach here only for member using decls. */
6627 if (DECL_DEPENDENT_P (t))
6629 r = do_class_using_decl
6630 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl),
6631 tsubst_copy (DECL_NAME (t), args, complain, in_decl));
6633 r = error_mark_node;
6638 TREE_CHAIN (r) = NULL_TREE;
6645 tree argvec = NULL_TREE;
6646 tree gen_tmpl = NULL_TREE;
6648 tree tmpl = NULL_TREE;
6650 tree type = NULL_TREE;
6653 if (TREE_CODE (t) == TYPE_DECL)
6655 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6656 if (TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM
6657 || t == TYPE_MAIN_DECL (TREE_TYPE (t)))
6659 /* If this is the canonical decl, we don't have to
6660 mess with instantiations, and often we can't (for
6661 typename, template type parms and such). Note that
6662 TYPE_NAME is not correct for the above test if
6663 we've copied the type for a typedef. */
6664 r = TYPE_NAME (type);
6669 /* Assume this is a non-local variable. */
6672 if (TYPE_P (CP_DECL_CONTEXT (t)))
6673 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args,
6675 in_decl, /*entering_scope=*/1);
6676 else if (DECL_NAMESPACE_SCOPE_P (t))
6677 ctx = DECL_CONTEXT (t);
6680 /* Subsequent calls to pushdecl will fill this in. */
6685 /* Check to see if we already have this specialization. */
6688 tmpl = DECL_TI_TEMPLATE (t);
6689 gen_tmpl = most_general_template (tmpl);
6690 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl);
6691 spec = retrieve_specialization (gen_tmpl, argvec,
6692 /*class_specializations_p=*/false);
6695 spec = retrieve_local_specialization (t);
6704 if (TREE_CODE (r) == VAR_DECL)
6706 /* Even if the original location is out of scope, the
6707 newly substituted one is not. */
6708 DECL_DEAD_FOR_LOCAL (r) = 0;
6709 DECL_INITIALIZED_P (r) = 0;
6710 DECL_TEMPLATE_INSTANTIATED (r) = 0;
6711 type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6712 if (type == error_mark_node)
6713 return error_mark_node;
6714 type = complete_type (type);
6715 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r)
6716 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (t);
6717 type = check_var_type (DECL_NAME (r), type);
6719 if (DECL_HAS_VALUE_EXPR_P (t))
6721 tree ve = DECL_VALUE_EXPR (t);
6722 ve = tsubst_expr (ve, args, complain, in_decl);
6723 SET_DECL_VALUE_EXPR (r, ve);
6726 else if (DECL_SELF_REFERENCE_P (t))
6727 SET_DECL_SELF_REFERENCE_P (r);
6728 TREE_TYPE (r) = type;
6729 cp_apply_type_quals_to_decl (cp_type_quals (type), r);
6730 DECL_CONTEXT (r) = ctx;
6731 /* Clear out the mangled name and RTL for the instantiation. */
6732 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE);
6733 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6734 SET_DECL_RTL (r, NULL_RTX);
6735 /* The initializer must not be expanded until it is required;
6737 DECL_INITIAL (r) = NULL_TREE;
6738 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
6739 SET_DECL_RTL (r, NULL_RTX);
6740 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;
6744 /* A static data member declaration is always marked
6745 external when it is declared in-class, even if an
6746 initializer is present. We mimic the non-template
6748 DECL_EXTERNAL (r) = 1;
6750 register_specialization (r, gen_tmpl, argvec, false);
6751 DECL_TEMPLATE_INFO (r) = tree_cons (tmpl, argvec, NULL_TREE);
6752 SET_DECL_IMPLICIT_INSTANTIATION (r);
6755 register_local_specialization (r, t);
6757 TREE_CHAIN (r) = NULL_TREE;
6766 /* Restore the file and line information. */
6767 input_location = saved_loc;
6772 /* Substitute into the ARG_TYPES of a function type. */
6775 tsubst_arg_types (tree arg_types,
6777 tsubst_flags_t complain,
6780 tree remaining_arg_types;
6783 tree result = NULL_TREE;
6785 if (!arg_types || arg_types == void_list_node)
6788 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types),
6789 args, complain, in_decl);
6790 if (remaining_arg_types == error_mark_node)
6791 return error_mark_node;
6793 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl);
6794 if (type == error_mark_node)
6795 return error_mark_node;
6796 if (VOID_TYPE_P (type))
6798 if (complain & tf_error)
6800 error ("invalid parameter type %qT", type);
6802 error ("in declaration %q+D", in_decl);
6804 return error_mark_node;
6807 /* Do array-to-pointer, function-to-pointer conversion, and ignore
6808 top-level qualifiers as required. */
6809 type = TYPE_MAIN_VARIANT (type_decays_to (type));
6811 /* We do not substitute into default arguments here. The standard
6812 mandates that they be instantiated only when needed, which is
6813 done in build_over_call. */
6814 default_arg = TREE_PURPOSE (arg_types);
6816 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG)
6818 /* We've instantiated a template before its default arguments
6819 have been parsed. This can happen for a nested template
6820 class, and is not an error unless we require the default
6821 argument in a call of this function. */
6822 result = tree_cons (default_arg, type, remaining_arg_types);
6823 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), result);
6826 result = hash_tree_cons (default_arg, type, remaining_arg_types);
6831 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does
6832 *not* handle the exception-specification for FNTYPE, because the
6833 initial substitution of explicitly provided template parameters
6834 during argument deduction forbids substitution into the
6835 exception-specification:
6839 All references in the function type of the function template to the
6840 corresponding template parameters are replaced by the specified tem-
6841 plate argument values. If a substitution in a template parameter or
6842 in the function type of the function template results in an invalid
6843 type, type deduction fails. [Note: The equivalent substitution in
6844 exception specifications is done only when the function is instanti-
6845 ated, at which point a program is ill-formed if the substitution
6846 results in an invalid type.] */
6849 tsubst_function_type (tree t,
6851 tsubst_flags_t complain,
6858 /* The TYPE_CONTEXT is not used for function/method types. */
6859 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE);
6861 /* Substitute the return type. */
6862 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
6863 if (return_type == error_mark_node)
6864 return error_mark_node;
6865 /* The standard does not presently indicate that creation of a
6866 function type with an invalid return type is a deduction failure.
6867 However, that is clearly analogous to creating an array of "void"
6868 or a reference to a reference. This is core issue #486. */
6869 if (TREE_CODE (return_type) == ARRAY_TYPE
6870 || TREE_CODE (return_type) == FUNCTION_TYPE)
6872 if (complain & tf_error)
6874 if (TREE_CODE (return_type) == ARRAY_TYPE)
6875 error ("function returning an array");
6877 error ("function returning a function");
6879 return error_mark_node;
6882 /* Substitute the argument types. */
6883 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args,
6885 if (arg_types == error_mark_node)
6886 return error_mark_node;
6888 /* Construct a new type node and return it. */
6889 if (TREE_CODE (t) == FUNCTION_TYPE)
6890 fntype = build_function_type (return_type, arg_types);
6893 tree r = TREE_TYPE (TREE_VALUE (arg_types));
6894 if (! IS_AGGR_TYPE (r))
6898 Type deduction may fail for any of the following
6901 -- Attempting to create "pointer to member of T" when T
6902 is not a class type. */
6903 if (complain & tf_error)
6904 error ("creating pointer to member function of non-class type %qT",
6906 return error_mark_node;
6909 fntype = build_method_type_directly (r, return_type,
6910 TREE_CHAIN (arg_types));
6912 fntype = cp_build_qualified_type_real (fntype, TYPE_QUALS (t), complain);
6913 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t));
6918 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template
6919 ARGS into that specification, and return the substituted
6920 specification. If there is no specification, return NULL_TREE. */
6923 tsubst_exception_specification (tree fntype,
6925 tsubst_flags_t complain,
6931 specs = TYPE_RAISES_EXCEPTIONS (fntype);
6932 new_specs = NULL_TREE;
6935 if (! TREE_VALUE (specs))
6941 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl);
6942 if (spec == error_mark_node)
6944 new_specs = add_exception_specifier (new_specs, spec, complain);
6945 specs = TREE_CHAIN (specs);
6951 /* Substitute into the PARMS of a call-declarator. */
6954 tsubst_call_declarator_parms (tree parms,
6956 tsubst_flags_t complain,
6963 if (!parms || parms == void_list_node)
6966 new_parms = tsubst_call_declarator_parms (TREE_CHAIN (parms),
6967 args, complain, in_decl);
6969 /* Figure out the type of this parameter. */
6970 type = tsubst (TREE_VALUE (parms), args, complain, in_decl);
6972 /* Figure out the default argument as well. Note that we use
6973 tsubst_expr since the default argument is really an expression. */
6974 defarg = tsubst_expr (TREE_PURPOSE (parms), args, complain, in_decl);
6976 /* Chain this parameter on to the front of those we have already
6977 processed. We don't use hash_tree_cons because that function
6978 doesn't check TREE_PARMLIST. */
6979 new_parms = tree_cons (defarg, type, new_parms);
6984 /* Take the tree structure T and replace template parameters used
6985 therein with the argument vector ARGS. IN_DECL is an associated
6986 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE.
6987 Issue error and warning messages under control of COMPLAIN. Note
6988 that we must be relatively non-tolerant of extensions here, in
6989 order to preserve conformance; if we allow substitutions that
6990 should not be allowed, we may allow argument deductions that should
6991 not succeed, and therefore report ambiguous overload situations
6992 where there are none. In theory, we could allow the substitution,
6993 but indicate that it should have failed, and allow our caller to
6994 make sure that the right thing happens, but we don't try to do this
6997 This function is used for dealing with types, decls and the like;
6998 for expressions, use tsubst_expr or tsubst_copy. */
7001 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7005 if (t == NULL_TREE || t == error_mark_node
7006 || t == integer_type_node
7007 || t == void_type_node
7008 || t == char_type_node
7009 || t == unknown_type_node
7010 || TREE_CODE (t) == NAMESPACE_DECL)
7014 return tsubst_decl (t, args, complain);
7016 if (TREE_CODE (t) == IDENTIFIER_NODE)
7017 type = IDENTIFIER_TYPE_VALUE (t);
7019 type = TREE_TYPE (t);
7021 gcc_assert (type != unknown_type_node);
7024 && TREE_CODE (t) != TYPENAME_TYPE
7025 && TREE_CODE (t) != IDENTIFIER_NODE
7026 && TREE_CODE (t) != FUNCTION_TYPE
7027 && TREE_CODE (t) != METHOD_TYPE)
7028 type = tsubst (type, args, complain, in_decl);
7029 if (type == error_mark_node)
7030 return error_mark_node;
7032 switch (TREE_CODE (t))
7037 return tsubst_aggr_type (t, args, complain, in_decl,
7038 /*entering_scope=*/0);
7041 case IDENTIFIER_NODE:
7053 if (t == integer_type_node)
7056 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST
7057 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST)
7061 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0);
7063 /* The array dimension behaves like a non-type template arg,
7064 in that we want to fold it as much as possible. */
7065 max = tsubst_template_arg (omax, args, complain, in_decl);
7066 max = fold_decl_constant_value (max);
7068 if (integer_zerop (omax))
7070 /* Still allow an explicit array of size zero. */
7072 pedwarn ("creating array with size zero");
7074 else if (integer_zerop (max)
7075 || (TREE_CODE (max) == INTEGER_CST
7076 && INT_CST_LT (max, integer_zero_node)))
7080 Type deduction may fail for any of the following
7083 Attempting to create an array with a size that is
7084 zero or negative. */
7085 if (complain & tf_error)
7086 error ("creating array with size zero (%qE)", max);
7088 return error_mark_node;
7091 return compute_array_index_type (NULL_TREE, max);
7094 case TEMPLATE_TYPE_PARM:
7095 case TEMPLATE_TEMPLATE_PARM:
7096 case BOUND_TEMPLATE_TEMPLATE_PARM:
7097 case TEMPLATE_PARM_INDEX:
7102 tree arg = NULL_TREE;
7106 gcc_assert (TREE_VEC_LENGTH (args) > 0);
7107 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7108 || TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM
7109 || TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7111 idx = TEMPLATE_TYPE_IDX (t);
7112 level = TEMPLATE_TYPE_LEVEL (t);
7116 idx = TEMPLATE_PARM_IDX (t);
7117 level = TEMPLATE_PARM_LEVEL (t);
7120 levels = TMPL_ARGS_DEPTH (args);
7121 if (level <= levels)
7122 arg = TMPL_ARG (args, level, idx);
7124 if (arg == error_mark_node)
7125 return error_mark_node;
7126 else if (arg != NULL_TREE)
7128 if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
7130 gcc_assert (TYPE_P (arg));
7131 return cp_build_qualified_type_real
7132 (arg, cp_type_quals (arg) | cp_type_quals (t),
7133 complain | tf_ignore_bad_quals);
7135 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7137 /* We are processing a type constructed from a
7138 template template parameter. */
7139 tree argvec = tsubst (TYPE_TI_ARGS (t),
7140 args, complain, in_decl);
7141 if (argvec == error_mark_node)
7142 return error_mark_node;
7144 /* We can get a TEMPLATE_TEMPLATE_PARM here when we
7145 are resolving nested-types in the signature of a
7146 member function templates. Otherwise ARG is a
7147 TEMPLATE_DECL and is the real template to be
7149 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
7150 arg = TYPE_NAME (arg);
7152 r = lookup_template_class (arg,
7155 /*entering_scope=*/0,
7157 return cp_build_qualified_type_real
7158 (r, TYPE_QUALS (t), complain);
7161 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */
7166 /* This can happen during the attempted tsubst'ing in
7167 unify. This means that we don't yet have any information
7168 about the template parameter in question. */
7171 /* If we get here, we must have been looking at a parm for a
7172 more deeply nested template. Make a new version of this
7173 template parameter, but with a lower level. */
7174 switch (TREE_CODE (t))
7176 case TEMPLATE_TYPE_PARM:
7177 case TEMPLATE_TEMPLATE_PARM:
7178 case BOUND_TEMPLATE_TEMPLATE_PARM:
7179 if (cp_type_quals (t))
7181 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl);
7182 r = cp_build_qualified_type_real
7183 (r, cp_type_quals (t),
7184 complain | (TREE_CODE (t) == TEMPLATE_TYPE_PARM
7185 ? tf_ignore_bad_quals : 0));
7190 TEMPLATE_TYPE_PARM_INDEX (r)
7191 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t),
7193 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r);
7194 TYPE_MAIN_VARIANT (r) = r;
7195 TYPE_POINTER_TO (r) = NULL_TREE;
7196 TYPE_REFERENCE_TO (r) = NULL_TREE;
7198 if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM)
7200 tree argvec = tsubst (TYPE_TI_ARGS (t), args,
7202 if (argvec == error_mark_node)
7203 return error_mark_node;
7205 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r)
7206 = tree_cons (TYPE_TI_TEMPLATE (t), argvec, NULL_TREE);
7211 case TEMPLATE_PARM_INDEX:
7212 r = reduce_template_parm_level (t, type, levels);
7224 tree purpose, value, chain;
7226 if (t == void_list_node)
7229 purpose = TREE_PURPOSE (t);
7232 purpose = tsubst (purpose, args, complain, in_decl);
7233 if (purpose == error_mark_node)
7234 return error_mark_node;
7236 value = TREE_VALUE (t);
7239 value = tsubst (value, args, complain, in_decl);
7240 if (value == error_mark_node)
7241 return error_mark_node;
7243 chain = TREE_CHAIN (t);
7244 if (chain && chain != void_type_node)
7246 chain = tsubst (chain, args, complain, in_decl);
7247 if (chain == error_mark_node)
7248 return error_mark_node;
7250 if (purpose == TREE_PURPOSE (t)
7251 && value == TREE_VALUE (t)
7252 && chain == TREE_CHAIN (t))
7254 return hash_tree_cons (purpose, value, chain);
7258 /* We should never be tsubsting a binfo. */
7262 /* A vector of template arguments. */
7264 return tsubst_template_args (t, args, complain, in_decl);
7267 case REFERENCE_TYPE:
7269 enum tree_code code;
7271 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE)
7274 code = TREE_CODE (t);
7279 Type deduction may fail for any of the following
7282 -- Attempting to create a pointer to reference type.
7283 -- Attempting to create a reference to a reference type or
7284 a reference to void. */
7285 if (TREE_CODE (type) == REFERENCE_TYPE
7286 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE))
7288 static location_t last_loc;
7290 /* We keep track of the last time we issued this error
7291 message to avoid spewing a ton of messages during a
7292 single bad template instantiation. */
7293 if (complain & tf_error
7294 #ifdef USE_MAPPED_LOCATION
7295 && last_loc != input_location
7297 && (last_loc.line != input_line
7298 || last_loc.file != input_filename)
7302 if (TREE_CODE (type) == VOID_TYPE)
7303 error ("forming reference to void");
7305 error ("forming %s to reference type %qT",
7306 (code == POINTER_TYPE) ? "pointer" : "reference",
7308 last_loc = input_location;
7311 return error_mark_node;
7313 else if (code == POINTER_TYPE)
7315 r = build_pointer_type (type);
7316 if (TREE_CODE (type) == METHOD_TYPE)
7317 r = build_ptrmemfunc_type (r);
7320 r = build_reference_type (type);
7321 r = cp_build_qualified_type_real (r, TYPE_QUALS (t), complain);
7323 if (r != error_mark_node)
7324 /* Will this ever be needed for TYPE_..._TO values? */
7331 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl);
7332 if (r == error_mark_node || !IS_AGGR_TYPE (r))
7336 Type deduction may fail for any of the following
7339 -- Attempting to create "pointer to member of T" when T
7340 is not a class type. */
7341 if (complain & tf_error)
7342 error ("creating pointer to member of non-class type %qT", r);
7343 return error_mark_node;
7345 if (TREE_CODE (type) == REFERENCE_TYPE)
7347 if (complain & tf_error)
7348 error ("creating pointer to member reference type %qT", type);
7349 return error_mark_node;
7351 if (TREE_CODE (type) == VOID_TYPE)
7353 if (complain & tf_error)
7354 error ("creating pointer to member of type void");
7355 return error_mark_node;
7357 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
7358 if (TREE_CODE (type) == FUNCTION_TYPE)
7360 /* The type of the implicit object parameter gets its
7361 cv-qualifiers from the FUNCTION_TYPE. */
7363 tree this_type = cp_build_qualified_type (TYPE_MAIN_VARIANT (r),
7364 cp_type_quals (type));
7366 method_type = build_method_type_directly (this_type,
7368 TYPE_ARG_TYPES (type));
7369 memptr = build_ptrmemfunc_type (build_pointer_type (method_type));
7370 return cp_build_qualified_type_real (memptr, cp_type_quals (t),
7374 return cp_build_qualified_type_real (build_ptrmem_type (r, type),
7383 fntype = tsubst_function_type (t, args, complain, in_decl);
7384 if (fntype == error_mark_node)
7385 return error_mark_node;
7387 /* Substitute the exception specification. */
7388 specs = tsubst_exception_specification (t, args, complain,
7390 if (specs == error_mark_node)
7391 return error_mark_node;
7393 fntype = build_exception_variant (fntype, specs);
7398 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl);
7399 if (domain == error_mark_node)
7400 return error_mark_node;
7402 /* As an optimization, we avoid regenerating the array type if
7403 it will obviously be the same as T. */
7404 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t))
7407 /* These checks should match the ones in grokdeclarator.
7411 The deduction may fail for any of the following reasons:
7413 -- Attempting to create an array with an element type that
7414 is void, a function type, or a reference type, or [DR337]
7415 an abstract class type. */
7416 if (TREE_CODE (type) == VOID_TYPE
7417 || TREE_CODE (type) == FUNCTION_TYPE
7418 || TREE_CODE (type) == REFERENCE_TYPE)
7420 if (complain & tf_error)
7421 error ("creating array of %qT", type);
7422 return error_mark_node;
7424 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type))
7426 if (complain & tf_error)
7427 error ("creating array of %qT, which is an abstract class type",
7429 return error_mark_node;
7432 r = build_cplus_array_type (type, domain);
7439 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7440 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7442 if (e1 == error_mark_node || e2 == error_mark_node)
7443 return error_mark_node;
7445 return fold_build2 (TREE_CODE (t), TREE_TYPE (t), e1, e2);
7451 tree e = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7452 if (e == error_mark_node)
7453 return error_mark_node;
7455 return fold_build1 (TREE_CODE (t), TREE_TYPE (t), e);
7460 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7461 in_decl, /*entering_scope=*/1);
7462 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args,
7465 if (ctx == error_mark_node || f == error_mark_node)
7466 return error_mark_node;
7468 if (!IS_AGGR_TYPE (ctx))
7470 if (complain & tf_error)
7471 error ("%qT is not a class, struct, or union type", ctx);
7472 return error_mark_node;
7474 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx))
7476 /* Normally, make_typename_type does not require that the CTX
7477 have complete type in order to allow things like:
7479 template <class T> struct S { typename S<T>::X Y; };
7481 But, such constructs have already been resolved by this
7482 point, so here CTX really should have complete type, unless
7483 it's a partial instantiation. */
7484 ctx = complete_type (ctx);
7485 if (!COMPLETE_TYPE_P (ctx))
7487 if (complain & tf_error)
7488 cxx_incomplete_type_error (NULL_TREE, ctx);
7489 return error_mark_node;
7493 f = make_typename_type (ctx, f, typename_type,
7494 (complain & tf_error) | tf_keep_type_decl);
7495 if (f == error_mark_node)
7497 if (TREE_CODE (f) == TYPE_DECL)
7499 complain |= tf_ignore_bad_quals;
7503 if (TREE_CODE (f) != TYPENAME_TYPE)
7505 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE)
7506 error ("%qT resolves to %qT, which is not an enumeration type",
7508 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f))
7509 error ("%qT resolves to %qT, which is is not a class type",
7513 return cp_build_qualified_type_real
7514 (f, cp_type_quals (f) | cp_type_quals (t), complain);
7517 case UNBOUND_CLASS_TEMPLATE:
7519 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain,
7520 in_decl, /*entering_scope=*/1);
7521 tree name = TYPE_IDENTIFIER (t);
7522 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t));
7524 if (ctx == error_mark_node || name == error_mark_node)
7525 return error_mark_node;
7528 parm_list = tsubst_template_parms (parm_list, args, complain);
7529 return make_unbound_class_template (ctx, name, parm_list, complain);
7539 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7540 tree e2 = tsubst_expr (TREE_OPERAND (t, 1), args, complain, in_decl);
7541 if (e1 == error_mark_node || e2 == error_mark_node)
7542 return error_mark_node;
7544 return build_nt (ARRAY_REF, e1, e2, NULL_TREE, NULL_TREE);
7549 tree e1 = tsubst (TREE_OPERAND (t, 0), args, complain, in_decl);
7550 tree e2 = tsubst (TREE_OPERAND (t, 1), args, complain, in_decl);
7551 if (e1 == error_mark_node || e2 == error_mark_node)
7552 return error_mark_node;
7554 return build_qualified_name (/*type=*/NULL_TREE,
7555 e1, e2, QUALIFIED_NAME_IS_TEMPLATE (t));
7562 type = finish_typeof (tsubst_expr (TYPEOF_TYPE_EXPR (t), args,
7563 complain, in_decl));
7564 return cp_build_qualified_type_real (type,
7566 | cp_type_quals (type),
7571 sorry ("use of %qs in template",
7572 tree_code_name [(int) TREE_CODE (t)]);
7573 return error_mark_node;
7577 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the
7578 type of the expression on the left-hand side of the "." or "->"
7582 tsubst_baselink (tree baselink, tree object_type,
7583 tree args, tsubst_flags_t complain, tree in_decl)
7586 tree qualifying_scope;
7588 tree template_args = 0;
7589 bool template_id_p = false;
7591 /* A baselink indicates a function from a base class. The
7592 BASELINK_ACCESS_BINFO and BASELINK_BINFO are going to have
7593 non-dependent types; otherwise, the lookup could not have
7594 succeeded. However, they may indicate bases of the template
7595 class, rather than the instantiated class.
7597 In addition, lookups that were not ambiguous before may be
7598 ambiguous now. Therefore, we perform the lookup again. */
7599 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink));
7600 fns = BASELINK_FUNCTIONS (baselink);
7601 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR)
7603 template_id_p = true;
7604 template_args = TREE_OPERAND (fns, 1);
7605 fns = TREE_OPERAND (fns, 0);
7607 template_args = tsubst_template_args (template_args, args,
7610 name = DECL_NAME (get_first_fn (fns));
7611 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1);
7613 /* If lookup found a single function, mark it as used at this
7614 point. (If it lookup found multiple functions the one selected
7615 later by overload resolution will be marked as used at that
7617 if (BASELINK_P (baselink))
7618 fns = BASELINK_FUNCTIONS (baselink);
7619 if (!template_id_p && !really_overloaded_fn (fns))
7620 mark_used (OVL_CURRENT (fns));
7622 /* Add back the template arguments, if present. */
7623 if (BASELINK_P (baselink) && template_id_p)
7624 BASELINK_FUNCTIONS (baselink)
7625 = build_nt (TEMPLATE_ID_EXPR,
7626 BASELINK_FUNCTIONS (baselink),
7630 object_type = current_class_type;
7631 return adjust_result_of_qualified_name_lookup (baselink,
7636 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is
7637 true if the qualified-id will be a postfix-expression in-and-of
7638 itself; false if more of the postfix-expression follows the
7639 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand
7643 tsubst_qualified_id (tree qualified_id, tree args,
7644 tsubst_flags_t complain, tree in_decl,
7645 bool done, bool address_p)
7653 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF);
7655 /* Figure out what name to look up. */
7656 name = TREE_OPERAND (qualified_id, 1);
7657 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
7660 template_args = TREE_OPERAND (name, 1);
7662 template_args = tsubst_template_args (template_args, args,
7664 name = TREE_OPERAND (name, 0);
7668 is_template = false;
7669 template_args = NULL_TREE;
7672 /* Substitute into the qualifying scope. When there are no ARGS, we
7673 are just trying to simplify a non-dependent expression. In that
7674 case the qualifying scope may be dependent, and, in any case,
7675 substituting will not help. */
7676 scope = TREE_OPERAND (qualified_id, 0);
7679 scope = tsubst (scope, args, complain, in_decl);
7680 expr = tsubst_copy (name, args, complain, in_decl);
7685 if (dependent_type_p (scope))
7686 return build_qualified_name (/*type=*/NULL_TREE,
7688 QUALIFIED_NAME_IS_TEMPLATE (qualified_id));
7690 if (!BASELINK_P (name) && !DECL_P (expr))
7692 if (TREE_CODE (expr) == BIT_NOT_EXPR)
7693 /* If this were actually a destructor call, it would have been
7694 parsed as such by the parser. */
7695 expr = error_mark_node;
7697 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false);
7698 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL
7699 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL)
7701 if (complain & tf_error)
7703 error ("dependent-name %qE is parsed as a non-type, but "
7704 "instantiation yields a type", qualified_id);
7705 inform ("say %<typename %E%> if a type is meant", qualified_id);
7707 return error_mark_node;
7713 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE,
7715 /* Remember that there was a reference to this entity. */
7719 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST)
7721 if (complain & tf_error)
7722 qualified_name_lookup_error (scope,
7723 TREE_OPERAND (qualified_id, 1),
7725 return error_mark_node;
7729 expr = lookup_template_function (expr, template_args);
7731 if (expr == error_mark_node && complain & tf_error)
7732 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1),
7734 else if (TYPE_P (scope))
7736 expr = (adjust_result_of_qualified_name_lookup
7737 (expr, scope, current_class_type));
7738 expr = (finish_qualified_id_expr
7739 (scope, expr, done, address_p,
7740 QUALIFIED_NAME_IS_TEMPLATE (qualified_id),
7741 /*template_arg_p=*/false));
7744 if (TREE_CODE (expr) != SCOPE_REF)
7745 expr = convert_from_reference (expr);
7750 /* Like tsubst, but deals with expressions. This function just replaces
7751 template parms; to finish processing the resultant expression, use
7755 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl)
7757 enum tree_code code;
7760 if (t == NULL_TREE || t == error_mark_node)
7763 code = TREE_CODE (t);
7768 r = retrieve_local_specialization (t);
7769 gcc_assert (r != NULL);
7778 if (DECL_TEMPLATE_PARM_P (t))
7779 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl);
7780 /* There is no need to substitute into namespace-scope
7782 if (DECL_NAMESPACE_SCOPE_P (t))
7784 /* If ARGS is NULL, then T is known to be non-dependent. */
7785 if (args == NULL_TREE)
7786 return integral_constant_value (t);
7788 /* Unfortunately, we cannot just call lookup_name here.
7791 template <int I> int f() {
7793 struct S { void g() { E e = a; } };
7796 When we instantiate f<7>::S::g(), say, lookup_name is not
7797 clever enough to find f<7>::a. */
7799 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl,
7800 /*entering_scope=*/0);
7802 for (v = TYPE_VALUES (enum_type);
7805 if (TREE_PURPOSE (v) == DECL_NAME (t))
7806 return TREE_VALUE (v);
7808 /* We didn't find the name. That should never happen; if
7809 name-lookup found it during preliminary parsing, we
7810 should find it again here during instantiation. */
7816 if (DECL_CONTEXT (t))
7820 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl,
7821 /*entering_scope=*/1);
7822 if (ctx != DECL_CONTEXT (t))
7824 tree r = lookup_field (ctx, DECL_NAME (t), 0, false);
7827 if (complain & tf_error)
7828 error ("using invalid field %qD", t);
7829 return error_mark_node;
7839 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t))
7840 || local_variable_p (t))
7841 t = tsubst (t, args, complain, in_decl);
7846 return tsubst_baselink (t, current_class_type, args, complain, in_decl);
7849 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t))
7850 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)),
7851 args, complain, in_decl);
7852 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t))
7853 return tsubst (t, args, complain, in_decl);
7854 else if (DECL_CLASS_SCOPE_P (t)
7855 && uses_template_parms (DECL_CONTEXT (t)))
7857 /* Template template argument like the following example need
7860 template <template <class> class TT> struct C {};
7861 template <class T> struct D {
7862 template <class U> struct E {};
7867 We are processing the template argument `E' in #1 for
7868 the template instantiation #2. Originally, `E' is a
7869 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we
7870 have to substitute this with one having context `D<int>'. */
7872 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl);
7873 return lookup_field (context, DECL_NAME(t), 0, false);
7876 /* Ordinary template template argument. */
7880 case REINTERPRET_CAST_EXPR:
7881 case CONST_CAST_EXPR:
7882 case STATIC_CAST_EXPR:
7883 case DYNAMIC_CAST_EXPR:
7886 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7887 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7891 case TRUTH_NOT_EXPR:
7894 case UNARY_PLUS_EXPR: /* Unary + */
7903 (code, tsubst (TREE_TYPE (t), args, complain, in_decl),
7904 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl));
7911 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl);
7912 name = TREE_OPERAND (t, 1);
7913 if (TREE_CODE (name) == BIT_NOT_EXPR)
7915 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7917 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7919 else if (TREE_CODE (name) == SCOPE_REF
7920 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR)
7922 tree base = tsubst_copy (TREE_OPERAND (name, 0), args,
7924 name = TREE_OPERAND (name, 1);
7925 name = tsubst_copy (TREE_OPERAND (name, 0), args,
7927 name = build1 (BIT_NOT_EXPR, NULL_TREE, name);
7928 name = build_qualified_name (/*type=*/NULL_TREE,
7930 /*template_p=*/false);
7932 else if (TREE_CODE (name) == BASELINK)
7933 name = tsubst_baselink (name,
7934 non_reference (TREE_TYPE (object)),
7938 name = tsubst_copy (name, args, complain, in_decl);
7939 return build_nt (COMPONENT_REF, object, name, NULL_TREE);
7945 case TRUNC_DIV_EXPR:
7947 case FLOOR_DIV_EXPR:
7948 case ROUND_DIV_EXPR:
7949 case EXACT_DIV_EXPR:
7953 case TRUNC_MOD_EXPR:
7954 case FLOOR_MOD_EXPR:
7955 case TRUTH_ANDIF_EXPR:
7956 case TRUTH_ORIF_EXPR:
7957 case TRUTH_AND_EXPR:
7974 case PREDECREMENT_EXPR:
7975 case PREINCREMENT_EXPR:
7976 case POSTDECREMENT_EXPR:
7977 case POSTINCREMENT_EXPR:
7979 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7980 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
7983 return build_qualified_name (/*type=*/NULL_TREE,
7984 tsubst_copy (TREE_OPERAND (t, 0),
7985 args, complain, in_decl),
7986 tsubst_copy (TREE_OPERAND (t, 1),
7987 args, complain, in_decl),
7988 QUALIFIED_NAME_IS_TEMPLATE (t));
7993 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
7994 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
7995 NULL_TREE, NULL_TREE);
7998 return build_nt (code,
7999 tsubst_copy (TREE_OPERAND (t, 0), args,
8001 tsubst_copy (TREE_OPERAND (t, 1), args, complain,
8007 case PSEUDO_DTOR_EXPR:
8010 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8011 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
8012 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
8013 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8020 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8021 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl),
8022 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl));
8023 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t);
8030 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl),
8031 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl));
8032 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t);
8033 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t);
8037 case TEMPLATE_ID_EXPR:
8039 /* Substituted template arguments */
8040 tree fn = TREE_OPERAND (t, 0);
8041 tree targs = TREE_OPERAND (t, 1);
8043 fn = tsubst_copy (fn, args, complain, in_decl);
8045 targs = tsubst_template_args (targs, args, complain, in_decl);
8047 return lookup_template_function (fn, targs);
8052 tree purpose, value, chain;
8054 if (t == void_list_node)
8057 purpose = TREE_PURPOSE (t);
8059 purpose = tsubst_copy (purpose, args, complain, in_decl);
8060 value = TREE_VALUE (t);
8062 value = tsubst_copy (value, args, complain, in_decl);
8063 chain = TREE_CHAIN (t);
8064 if (chain && chain != void_type_node)
8065 chain = tsubst_copy (chain, args, complain, in_decl);
8066 if (purpose == TREE_PURPOSE (t)
8067 && value == TREE_VALUE (t)
8068 && chain == TREE_CHAIN (t))
8070 return tree_cons (purpose, value, chain);
8077 case TEMPLATE_TYPE_PARM:
8078 case TEMPLATE_TEMPLATE_PARM:
8079 case BOUND_TEMPLATE_TEMPLATE_PARM:
8080 case TEMPLATE_PARM_INDEX:
8082 case REFERENCE_TYPE:
8088 case UNBOUND_CLASS_TEMPLATE:
8091 return tsubst (t, args, complain, in_decl);
8093 case IDENTIFIER_NODE:
8094 if (IDENTIFIER_TYPENAME_P (t))
8096 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8097 return mangle_conv_op_name_for_type (new_type);
8103 /* This is handled by tsubst_copy_and_build. */
8107 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain,
8109 tsubst (TREE_TYPE (t), args, complain, in_decl));
8111 case CLEANUP_POINT_EXPR:
8112 /* We shouldn't have built any of these during initial template
8113 generation. Instead, they should be built during instantiation
8114 in response to the saved STMT_IS_FULL_EXPR_P setting. */
8122 /* Like tsubst_copy for expressions, etc. but also does semantic
8126 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl)
8130 if (t == NULL_TREE || t == error_mark_node)
8133 if (EXPR_HAS_LOCATION (t))
8134 input_location = EXPR_LOCATION (t);
8135 if (STATEMENT_CODE_P (TREE_CODE (t)))
8136 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t);
8138 switch (TREE_CODE (t))
8140 case STATEMENT_LIST:
8142 tree_stmt_iterator i;
8143 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i))
8144 tsubst_expr (tsi_stmt (i), args, complain, in_decl);
8148 case CTOR_INITIALIZER:
8149 finish_mem_initializers (tsubst_initializer_list
8150 (TREE_OPERAND (t, 0), args));
8154 finish_return_stmt (tsubst_expr (TREE_OPERAND (t, 0),
8155 args, complain, in_decl));
8159 tmp = tsubst_expr (EXPR_STMT_EXPR (t), args, complain, in_decl);
8160 if (EXPR_STMT_STMT_EXPR_RESULT (t))
8161 finish_stmt_expr_expr (tmp, cur_stmt_expr);
8163 finish_expr_stmt (tmp);
8167 do_using_directive (tsubst_expr (USING_STMT_NAMESPACE (t),
8168 args, complain, in_decl));
8176 decl = DECL_EXPR_DECL (t);
8177 if (TREE_CODE (decl) == LABEL_DECL)
8178 finish_label_decl (DECL_NAME (decl));
8179 else if (TREE_CODE (decl) == USING_DECL)
8181 tree scope = USING_DECL_SCOPE (decl);
8182 tree name = DECL_NAME (decl);
8185 scope = tsubst_expr (scope, args, complain, in_decl);
8186 decl = lookup_qualified_name (scope, name,
8187 /*is_type_p=*/false,
8188 /*complain=*/false);
8189 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST)
8190 qualified_name_lookup_error (scope, name, decl);
8192 do_local_using_decl (decl, scope, name);
8196 init = DECL_INITIAL (decl);
8197 decl = tsubst (decl, args, complain, in_decl);
8198 if (decl != error_mark_node)
8201 DECL_INITIAL (decl) = error_mark_node;
8202 /* By marking the declaration as instantiated, we avoid
8203 trying to instantiate it. Since instantiate_decl can't
8204 handle local variables, and since we've already done
8205 all that needs to be done, that's the right thing to
8207 if (TREE_CODE (decl) == VAR_DECL)
8208 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8209 if (TREE_CODE (decl) == VAR_DECL
8210 && ANON_AGGR_TYPE_P (TREE_TYPE (decl)))
8211 /* Anonymous aggregates are a special case. */
8212 finish_anon_union (decl);
8215 maybe_push_decl (decl);
8216 if (TREE_CODE (decl) == VAR_DECL
8217 && DECL_PRETTY_FUNCTION_P (decl))
8219 /* For __PRETTY_FUNCTION__ we have to adjust the
8221 const char *const name
8222 = cxx_printable_name (current_function_decl, 2);
8223 init = cp_fname_init (name, &TREE_TYPE (decl));
8226 init = tsubst_expr (init, args, complain, in_decl);
8227 cp_finish_decl (decl, init, NULL_TREE, 0);
8232 /* A DECL_EXPR can also be used as an expression, in the condition
8233 clause of an if/for/while construct. */
8238 stmt = begin_for_stmt ();
8239 tsubst_expr (FOR_INIT_STMT (t), args, complain, in_decl);
8240 finish_for_init_stmt (stmt);
8241 tmp = tsubst_expr (FOR_COND (t), args, complain, in_decl);
8242 finish_for_cond (tmp, stmt);
8243 tmp = tsubst_expr (FOR_EXPR (t), args, complain, in_decl);
8244 finish_for_expr (tmp, stmt);
8245 tsubst_expr (FOR_BODY (t), args, complain, in_decl);
8246 finish_for_stmt (stmt);
8250 stmt = begin_while_stmt ();
8251 tmp = tsubst_expr (WHILE_COND (t), args, complain, in_decl);
8252 finish_while_stmt_cond (tmp, stmt);
8253 tsubst_expr (WHILE_BODY (t), args, complain, in_decl);
8254 finish_while_stmt (stmt);
8258 stmt = begin_do_stmt ();
8259 tsubst_expr (DO_BODY (t), args, complain, in_decl);
8260 finish_do_body (stmt);
8261 tmp = tsubst_expr (DO_COND (t), args, complain, in_decl);
8262 finish_do_stmt (tmp, stmt);
8266 stmt = begin_if_stmt ();
8267 tmp = tsubst_expr (IF_COND (t), args, complain, in_decl);
8268 finish_if_stmt_cond (tmp, stmt);
8269 tsubst_expr (THEN_CLAUSE (t), args, complain, in_decl);
8270 finish_then_clause (stmt);
8272 if (ELSE_CLAUSE (t))
8274 begin_else_clause (stmt);
8275 tsubst_expr (ELSE_CLAUSE (t), args, complain, in_decl);
8276 finish_else_clause (stmt);
8279 finish_if_stmt (stmt);
8283 if (BIND_EXPR_BODY_BLOCK (t))
8284 stmt = begin_function_body ();
8286 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t)
8287 ? BCS_TRY_BLOCK : 0);
8289 tsubst_expr (BIND_EXPR_BODY (t), args, complain, in_decl);
8291 if (BIND_EXPR_BODY_BLOCK (t))
8292 finish_function_body (stmt);
8294 finish_compound_stmt (stmt);
8298 finish_break_stmt ();
8302 finish_continue_stmt ();
8306 stmt = begin_switch_stmt ();
8307 tmp = tsubst_expr (SWITCH_STMT_COND (t), args, complain, in_decl);
8308 finish_switch_cond (tmp, stmt);
8309 tsubst_expr (SWITCH_STMT_BODY (t), args, complain, in_decl);
8310 finish_switch_stmt (stmt);
8313 case CASE_LABEL_EXPR:
8314 finish_case_label (tsubst_expr (CASE_LOW (t), args, complain, in_decl),
8315 tsubst_expr (CASE_HIGH (t), args, complain,
8320 finish_label_stmt (DECL_NAME (LABEL_EXPR_LABEL (t)));
8324 tmp = GOTO_DESTINATION (t);
8325 if (TREE_CODE (tmp) != LABEL_DECL)
8326 /* Computed goto's must be tsubst'd into. On the other hand,
8327 non-computed gotos must not be; the identifier in question
8328 will have no binding. */
8329 tmp = tsubst_expr (tmp, args, complain, in_decl);
8331 tmp = DECL_NAME (tmp);
8332 finish_goto_stmt (tmp);
8336 tmp = finish_asm_stmt
8337 (ASM_VOLATILE_P (t),
8338 tsubst_expr (ASM_STRING (t), args, complain, in_decl),
8339 tsubst_expr (ASM_OUTPUTS (t), args, complain, in_decl),
8340 tsubst_expr (ASM_INPUTS (t), args, complain, in_decl),
8341 tsubst_expr (ASM_CLOBBERS (t), args, complain, in_decl));
8343 tree asm_expr = tmp;
8344 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR)
8345 asm_expr = TREE_OPERAND (asm_expr, 0);
8346 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t);
8353 stmt = begin_try_block ();
8354 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8355 finish_cleanup_try_block (stmt);
8356 finish_cleanup (tsubst_expr (TRY_HANDLERS (t), args,
8362 if (FN_TRY_BLOCK_P (t))
8363 stmt = begin_function_try_block ();
8365 stmt = begin_try_block ();
8367 tsubst_expr (TRY_STMTS (t), args, complain, in_decl);
8369 if (FN_TRY_BLOCK_P (t))
8370 finish_function_try_block (stmt);
8372 finish_try_block (stmt);
8374 tsubst_expr (TRY_HANDLERS (t), args, complain, in_decl);
8375 if (FN_TRY_BLOCK_P (t))
8376 finish_function_handler_sequence (stmt);
8378 finish_handler_sequence (stmt);
8386 stmt = begin_handler ();
8387 if (HANDLER_PARMS (t))
8389 decl = HANDLER_PARMS (t);
8390 decl = tsubst (decl, args, complain, in_decl);
8391 /* Prevent instantiate_decl from trying to instantiate
8392 this variable. We've already done all that needs to be
8394 DECL_TEMPLATE_INSTANTIATED (decl) = 1;
8398 finish_handler_parms (decl, stmt);
8399 tsubst_expr (HANDLER_BODY (t), args, complain, in_decl);
8400 finish_handler (stmt);
8405 tsubst (TREE_TYPE (t), args, complain, NULL_TREE);
8409 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t)));
8411 return tsubst_copy_and_build (t, args, complain, in_decl,
8412 /*function_p=*/false);
8418 /* T is a postfix-expression that is not being used in a function
8419 call. Return the substituted version of T. */
8422 tsubst_non_call_postfix_expression (tree t, tree args,
8423 tsubst_flags_t complain,
8426 if (TREE_CODE (t) == SCOPE_REF)
8427 t = tsubst_qualified_id (t, args, complain, in_decl,
8428 /*done=*/false, /*address_p=*/false);
8430 t = tsubst_copy_and_build (t, args, complain, in_decl,
8431 /*function_p=*/false);
8436 /* Like tsubst but deals with expressions and performs semantic
8437 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */
8440 tsubst_copy_and_build (tree t,
8442 tsubst_flags_t complain,
8446 #define RECUR(NODE) \
8447 tsubst_copy_and_build (NODE, args, complain, in_decl, /*function_p=*/false)
8451 if (t == NULL_TREE || t == error_mark_node)
8454 switch (TREE_CODE (t))
8459 case IDENTIFIER_NODE:
8463 bool non_integral_constant_expression_p;
8464 const char *error_msg;
8466 if (IDENTIFIER_TYPENAME_P (t))
8468 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8469 t = mangle_conv_op_name_for_type (new_type);
8472 /* Look up the name. */
8473 decl = lookup_name (t, 0);
8475 /* By convention, expressions use ERROR_MARK_NODE to indicate
8476 failure, not NULL_TREE. */
8477 if (decl == NULL_TREE)
8478 decl = error_mark_node;
8480 decl = finish_id_expression (t, decl, NULL_TREE,
8482 /*integral_constant_expression_p=*/false,
8483 /*allow_non_integral_constant_expression_p=*/false,
8484 &non_integral_constant_expression_p,
8485 /*template_p=*/false,
8487 /*address_p=*/false,
8488 /*template_arg_p=*/false,
8492 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE)
8493 decl = unqualified_name_lookup_error (decl);
8497 case TEMPLATE_ID_EXPR:
8500 tree template = RECUR (TREE_OPERAND (t, 0));
8501 tree targs = TREE_OPERAND (t, 1);
8504 targs = tsubst_template_args (targs, args, complain, in_decl);
8506 if (TREE_CODE (template) == COMPONENT_REF)
8508 object = TREE_OPERAND (template, 0);
8509 template = TREE_OPERAND (template, 1);
8513 template = lookup_template_function (template, targs);
8516 return build3 (COMPONENT_REF, TREE_TYPE (template),
8517 object, template, NULL_TREE);
8524 tree r = RECUR (TREE_OPERAND (t, 0));
8526 if (REFERENCE_REF_P (t))
8528 /* A type conversion to reference type will be enclosed in
8529 such an indirect ref, but the substitution of the cast
8530 will have also added such an indirect ref. */
8531 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE)
8532 r = convert_from_reference (r);
8535 r = build_x_indirect_ref (r, "unary *");
8541 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8542 RECUR (TREE_OPERAND (t, 0)));
8545 return build_functional_cast
8546 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8547 RECUR (TREE_OPERAND (t, 0)));
8549 case REINTERPRET_CAST_EXPR:
8550 return build_reinterpret_cast
8551 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8552 RECUR (TREE_OPERAND (t, 0)));
8554 case CONST_CAST_EXPR:
8555 return build_const_cast
8556 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8557 RECUR (TREE_OPERAND (t, 0)));
8559 case DYNAMIC_CAST_EXPR:
8560 return build_dynamic_cast
8561 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8562 RECUR (TREE_OPERAND (t, 0)));
8564 case STATIC_CAST_EXPR:
8565 return build_static_cast
8566 (tsubst (TREE_TYPE (t), args, complain, in_decl),
8567 RECUR (TREE_OPERAND (t, 0)));
8569 case POSTDECREMENT_EXPR:
8570 case POSTINCREMENT_EXPR:
8571 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8572 args, complain, in_decl);
8573 return build_x_unary_op (TREE_CODE (t), op1);
8575 case PREDECREMENT_EXPR:
8576 case PREINCREMENT_EXPR:
8580 case TRUTH_NOT_EXPR:
8581 case UNARY_PLUS_EXPR: /* Unary + */
8584 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)));
8587 op1 = TREE_OPERAND (t, 0);
8588 if (TREE_CODE (op1) == SCOPE_REF)
8589 op1 = tsubst_qualified_id (op1, args, complain, in_decl,
8590 /*done=*/true, /*address_p=*/true);
8592 op1 = tsubst_non_call_postfix_expression (op1, args, complain,
8594 if (TREE_CODE (op1) == LABEL_DECL)
8595 return finish_label_address_expr (DECL_NAME (op1));
8596 return build_x_unary_op (ADDR_EXPR, op1);
8601 case TRUNC_DIV_EXPR:
8603 case FLOOR_DIV_EXPR:
8604 case ROUND_DIV_EXPR:
8605 case EXACT_DIV_EXPR:
8609 case TRUNC_MOD_EXPR:
8610 case FLOOR_MOD_EXPR:
8611 case TRUTH_ANDIF_EXPR:
8612 case TRUTH_ORIF_EXPR:
8613 case TRUTH_AND_EXPR:
8629 return build_x_binary_op
8631 RECUR (TREE_OPERAND (t, 0)),
8632 RECUR (TREE_OPERAND (t, 1)),
8633 /*overloaded_p=*/NULL);
8636 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true,
8637 /*address_p=*/false);
8639 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8640 args, complain, in_decl);
8641 return build_x_binary_op (ARRAY_REF, op1, RECUR (TREE_OPERAND (t, 1)),
8642 /*overloaded_p=*/NULL);
8646 op1 = TREE_OPERAND (t, 0);
8649 /* When there are no ARGS, we are trying to evaluate a
8650 non-dependent expression from the parser. Trying to do
8651 the substitutions may not work. */
8653 op1 = TREE_TYPE (op1);
8662 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), true);
8664 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t));
8668 tree r = build_x_modify_expr
8669 (RECUR (TREE_OPERAND (t, 0)),
8670 TREE_CODE (TREE_OPERAND (t, 1)),
8671 RECUR (TREE_OPERAND (t, 2)));
8672 /* TREE_NO_WARNING must be set if either the expression was
8673 parenthesized or it uses an operator such as >>= rather
8674 than plain assignment. In the former case, it was already
8675 set and must be copied. In the latter case,
8676 build_x_modify_expr sets it and it must not be reset
8678 if (TREE_NO_WARNING (t))
8679 TREE_NO_WARNING (r) = TREE_NO_WARNING (t);
8684 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8685 args, complain, in_decl);
8686 /* Remember that there was a reference to this entity. */
8689 return build_x_arrow (op1);
8693 (RECUR (TREE_OPERAND (t, 0)),
8694 RECUR (TREE_OPERAND (t, 1)),
8695 RECUR (TREE_OPERAND (t, 2)),
8696 RECUR (TREE_OPERAND (t, 3)),
8697 NEW_EXPR_USE_GLOBAL (t));
8700 return delete_sanity
8701 (RECUR (TREE_OPERAND (t, 0)),
8702 RECUR (TREE_OPERAND (t, 1)),
8703 DELETE_EXPR_USE_VEC (t),
8704 DELETE_EXPR_USE_GLOBAL (t));
8707 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)),
8708 RECUR (TREE_OPERAND (t, 1)));
8717 function = TREE_OPERAND (t, 0);
8718 /* When we parsed the expression, we determined whether or
8719 not Koenig lookup should be performed. */
8720 koenig_p = KOENIG_LOOKUP_P (t);
8721 if (TREE_CODE (function) == SCOPE_REF)
8724 function = tsubst_qualified_id (function, args, complain, in_decl,
8726 /*address_p=*/false);
8730 if (TREE_CODE (function) == COMPONENT_REF)
8732 tree op = TREE_OPERAND (function, 1);
8734 qualified_p = (TREE_CODE (op) == SCOPE_REF
8736 && BASELINK_QUALIFIED_P (op)));
8739 qualified_p = false;
8741 function = tsubst_copy_and_build (function, args, complain,
8744 if (BASELINK_P (function))
8748 call_args = RECUR (TREE_OPERAND (t, 1));
8750 /* We do not perform argument-dependent lookup if normal
8751 lookup finds a non-function, in accordance with the
8752 expected resolution of DR 218. */
8754 && ((is_overloaded_fn (function)
8755 /* If lookup found a member function, the Koenig lookup is
8756 not appropriate, even if an unqualified-name was used
8757 to denote the function. */
8758 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function)))
8759 || TREE_CODE (function) == IDENTIFIER_NODE))
8760 function = perform_koenig_lookup (function, call_args);
8762 if (TREE_CODE (function) == IDENTIFIER_NODE)
8764 unqualified_name_lookup_error (function);
8765 return error_mark_node;
8768 /* Remember that there was a reference to this entity. */
8769 if (DECL_P (function))
8770 mark_used (function);
8772 if (TREE_CODE (function) == OFFSET_REF)
8773 return build_offset_ref_call_from_tree (function, call_args);
8774 if (TREE_CODE (function) == COMPONENT_REF)
8776 if (!BASELINK_P (TREE_OPERAND (function, 1)))
8777 return finish_call_expr (function, call_args,
8778 /*disallow_virtual=*/false,
8779 /*koenig_p=*/false);
8781 return (build_new_method_call
8782 (TREE_OPERAND (function, 0),
8783 TREE_OPERAND (function, 1),
8784 call_args, NULL_TREE,
8785 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL));
8787 return finish_call_expr (function, call_args,
8788 /*disallow_virtual=*/qualified_p,
8793 return build_x_conditional_expr
8794 (RECUR (TREE_OPERAND (t, 0)),
8795 RECUR (TREE_OPERAND (t, 1)),
8796 RECUR (TREE_OPERAND (t, 2)));
8798 case PSEUDO_DTOR_EXPR:
8799 return finish_pseudo_destructor_expr
8800 (RECUR (TREE_OPERAND (t, 0)),
8801 RECUR (TREE_OPERAND (t, 1)),
8802 RECUR (TREE_OPERAND (t, 2)));
8806 tree purpose, value, chain;
8808 if (t == void_list_node)
8811 purpose = TREE_PURPOSE (t);
8813 purpose = RECUR (purpose);
8814 value = TREE_VALUE (t);
8816 value = RECUR (value);
8817 chain = TREE_CHAIN (t);
8818 if (chain && chain != void_type_node)
8819 chain = RECUR (chain);
8820 if (purpose == TREE_PURPOSE (t)
8821 && value == TREE_VALUE (t)
8822 && chain == TREE_CHAIN (t))
8824 return tree_cons (purpose, value, chain);
8832 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0),
8833 args, complain, in_decl);
8834 /* Remember that there was a reference to this entity. */
8835 if (DECL_P (object))
8838 member = TREE_OPERAND (t, 1);
8839 if (BASELINK_P (member))
8840 member = tsubst_baselink (member,
8841 non_reference (TREE_TYPE (object)),
8842 args, complain, in_decl);
8844 member = tsubst_copy (member, args, complain, in_decl);
8846 if (member == error_mark_node)
8847 return error_mark_node;
8848 else if (!CLASS_TYPE_P (TREE_TYPE (object)))
8850 if (TREE_CODE (member) == BIT_NOT_EXPR)
8851 return finish_pseudo_destructor_expr (object,
8853 TREE_TYPE (object));
8854 else if (TREE_CODE (member) == SCOPE_REF
8855 && (TREE_CODE (TREE_OPERAND (member, 1)) == BIT_NOT_EXPR))
8856 return finish_pseudo_destructor_expr (object,
8858 TREE_TYPE (object));
8860 else if (TREE_CODE (member) == SCOPE_REF
8861 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR)
8866 /* Lookup the template functions now that we know what the
8868 tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0);
8869 args = TREE_OPERAND (TREE_OPERAND (member, 1), 1);
8870 member = lookup_qualified_name (TREE_OPERAND (member, 0), tmpl,
8871 /*is_type_p=*/false,
8872 /*complain=*/false);
8873 if (BASELINK_P (member))
8875 BASELINK_FUNCTIONS (member)
8876 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member),
8878 member = (adjust_result_of_qualified_name_lookup
8879 (member, BINFO_TYPE (BASELINK_BINFO (member)),
8880 TREE_TYPE (object)));
8884 qualified_name_lookup_error (TREE_TYPE (object), tmpl,
8886 return error_mark_node;
8889 else if (TREE_CODE (member) == SCOPE_REF
8890 && !CLASS_TYPE_P (TREE_OPERAND (member, 0))
8891 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL)
8893 if (complain & tf_error)
8895 if (TYPE_P (TREE_OPERAND (member, 0)))
8896 error ("%qT is not a class or namespace",
8897 TREE_OPERAND (member, 0));
8899 error ("%qD is not a class or namespace",
8900 TREE_OPERAND (member, 0));
8902 return error_mark_node;
8904 else if (TREE_CODE (member) == FIELD_DECL)
8905 return finish_non_static_data_member (member, object, NULL_TREE);
8907 return finish_class_member_access_expr (object, member,
8908 /*template_p=*/false);
8913 (RECUR (TREE_OPERAND (t, 0)));
8917 VEC(constructor_elt,gc) *n;
8918 constructor_elt *ce;
8919 unsigned HOST_WIDE_INT idx;
8921 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl);
8922 bool process_index_p;
8924 /* digest_init will do the wrong thing if we let it. */
8925 if (type && TYPE_PTRMEMFUNC_P (type))
8928 /* We do not want to process the index of aggregate
8929 initializers as they are identifier nodes which will be
8930 looked up by digest_init. */
8931 process_index_p = !(type && IS_AGGR_TYPE (type));
8933 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t));
8934 for (idx = 0; VEC_iterate (constructor_elt, n, idx, ce); idx++)
8936 if (ce->index && process_index_p)
8937 ce->index = RECUR (ce->index);
8938 ce->value = RECUR (ce->value);
8941 r = build_constructor (NULL_TREE, n);
8942 TREE_HAS_CONSTRUCTOR (r) = TREE_HAS_CONSTRUCTOR (t);
8945 return digest_init (type, r);
8951 tree operand_0 = RECUR (TREE_OPERAND (t, 0));
8952 if (TYPE_P (operand_0))
8953 return get_typeid (operand_0);
8954 return build_typeid (operand_0);
8964 tree r = tsubst_copy (t, args, complain, in_decl);
8966 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE)
8967 /* If the original type was a reference, we'll be wrapped in
8968 the appropriate INDIRECT_REF. */
8969 r = convert_from_reference (r);
8974 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)),
8975 tsubst_copy (TREE_TYPE (t), args, complain,
8979 return fold_offsetof (RECUR (TREE_OPERAND (t, 0)));
8983 tree old_stmt_expr = cur_stmt_expr;
8984 tree stmt_expr = begin_stmt_expr ();
8986 cur_stmt_expr = stmt_expr;
8987 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl);
8988 stmt_expr = finish_stmt_expr (stmt_expr, false);
8989 cur_stmt_expr = old_stmt_expr;
8995 t = tsubst_copy (t, args, complain, in_decl);
8996 /* As in finish_id_expression, we resolve enumeration constants
8997 to their underlying values. */
8998 if (TREE_CODE (t) == CONST_DECL)
8999 return DECL_INITIAL (t);
9003 /* Handle Objective-C++ constructs, if appropriate. */
9006 = objcp_tsubst_copy_and_build (t, args, complain,
9007 in_decl, /*function_p=*/false);
9011 return tsubst_copy (t, args, complain, in_decl);
9017 /* Verify that the instantiated ARGS are valid. For type arguments,
9018 make sure that the type's linkage is ok. For non-type arguments,
9019 make sure they are constants if they are integral or enumerations.
9020 Emit an error under control of COMPLAIN, and return TRUE on error. */
9023 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain)
9025 int ix, len = DECL_NTPARMS (tmpl);
9026 bool result = false;
9028 for (ix = 0; ix != len; ix++)
9030 tree t = TREE_VEC_ELT (args, ix);
9034 /* [basic.link]: A name with no linkage (notably, the name
9035 of a class or enumeration declared in a local scope)
9036 shall not be used to declare an entity with linkage.
9037 This implies that names with no linkage cannot be used as
9038 template arguments. */
9039 tree nt = no_linkage_check (t, /*relaxed_p=*/false);
9043 /* DR 488 makes use of a type with no linkage cause
9044 type deduction to fail. */
9045 if (complain & tf_error)
9047 if (TYPE_ANONYMOUS_P (nt))
9048 error ("%qT is/uses anonymous type", t);
9050 error ("%qT uses local type %qT", t, nt);
9054 /* In order to avoid all sorts of complications, we do not
9055 allow variably-modified types as template arguments. */
9056 else if (variably_modified_type_p (t, NULL_TREE))
9058 if (complain & tf_error)
9059 error ("%qT is a variably modified type", t);
9063 /* A non-type argument of integral or enumerated type must be a
9065 else if (TREE_TYPE (t)
9066 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t))
9067 && !TREE_CONSTANT (t))
9069 if (complain & tf_error)
9070 error ("integral expression %qE is not constant", t);
9074 if (result && (complain & tf_error))
9075 error (" trying to instantiate %qD", tmpl);
9079 /* Instantiate the indicated variable or function template TMPL with
9080 the template arguments in TARG_PTR. */
9083 instantiate_template (tree tmpl, tree targ_ptr, tsubst_flags_t complain)
9089 if (tmpl == error_mark_node)
9090 return error_mark_node;
9092 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL);
9094 /* If this function is a clone, handle it specially. */
9095 if (DECL_CLONED_FUNCTION_P (tmpl))
9100 spec = instantiate_template (DECL_CLONED_FUNCTION (tmpl), targ_ptr,
9102 if (spec == error_mark_node)
9103 return error_mark_node;
9105 /* Look for the clone. */
9106 FOR_EACH_CLONE (clone, spec)
9107 if (DECL_NAME (clone) == DECL_NAME (tmpl))
9109 /* We should always have found the clone by now. */
9114 /* Check to see if we already have this specialization. */
9115 spec = retrieve_specialization (tmpl, targ_ptr,
9116 /*class_specializations_p=*/false);
9117 if (spec != NULL_TREE)
9120 gen_tmpl = most_general_template (tmpl);
9121 if (tmpl != gen_tmpl)
9123 /* The TMPL is a partial instantiation. To get a full set of
9124 arguments we must add the arguments used to perform the
9125 partial instantiation. */
9126 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl),
9129 /* Check to see if we already have this specialization. */
9130 spec = retrieve_specialization (gen_tmpl, targ_ptr,
9131 /*class_specializations_p=*/false);
9132 if (spec != NULL_TREE)
9136 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr),
9138 return error_mark_node;
9140 /* We are building a FUNCTION_DECL, during which the access of its
9141 parameters and return types have to be checked. However this
9142 FUNCTION_DECL which is the desired context for access checking
9143 is not built yet. We solve this chicken-and-egg problem by
9144 deferring all checks until we have the FUNCTION_DECL. */
9145 push_deferring_access_checks (dk_deferred);
9147 /* Substitute template parameters. */
9148 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl),
9149 targ_ptr, complain, gen_tmpl);
9151 /* Now we know the specialization, compute access previously
9153 push_access_scope (fndecl);
9154 perform_deferred_access_checks ();
9155 pop_access_scope (fndecl);
9156 pop_deferring_access_checks ();
9158 /* The DECL_TI_TEMPLATE should always be the immediate parent
9159 template, not the most general template. */
9160 DECL_TI_TEMPLATE (fndecl) = tmpl;
9162 /* If we've just instantiated the main entry point for a function,
9163 instantiate all the alternate entry points as well. We do this
9164 by cloning the instantiation of the main entry point, not by
9165 instantiating the template clones. */
9166 if (TREE_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (TREE_CHAIN (gen_tmpl)))
9167 clone_function_decl (fndecl, /*update_method_vec_p=*/0);
9172 /* The FN is a TEMPLATE_DECL for a function. The ARGS are the
9173 arguments that are being used when calling it. TARGS is a vector
9174 into which the deduced template arguments are placed.
9176 Return zero for success, 2 for an incomplete match that doesn't resolve
9177 all the types, and 1 for complete failure. An error message will be
9178 printed only for an incomplete match.
9180 If FN is a conversion operator, or we are trying to produce a specific
9181 specialization, RETURN_TYPE is the return type desired.
9183 The EXPLICIT_TARGS are explicit template arguments provided via a
9186 The parameter STRICT is one of:
9189 We are deducing arguments for a function call, as in
9193 We are deducing arguments for a conversion function, as in
9197 We are deducing arguments when doing an explicit instantiation
9198 as in [temp.explicit], when determining an explicit specialization
9199 as in [temp.expl.spec], or when taking the address of a function
9200 template, as in [temp.deduct.funcaddr]. */
9203 fn_type_unification (tree fn,
9204 tree explicit_targs,
9208 unification_kind_t strict,
9215 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL);
9217 fntype = TREE_TYPE (fn);
9222 The specified template arguments must match the template
9223 parameters in kind (i.e., type, nontype, template), and there
9224 must not be more arguments than there are parameters;
9225 otherwise type deduction fails.
9227 Nontype arguments must match the types of the corresponding
9228 nontype template parameters, or must be convertible to the
9229 types of the corresponding nontype parameters as specified in
9230 _temp.arg.nontype_, otherwise type deduction fails.
9232 All references in the function type of the function template
9233 to the corresponding template parameters are replaced by the
9234 specified template argument values. If a substitution in a
9235 template parameter or in the function type of the function
9236 template results in an invalid type, type deduction fails. */
9238 tree converted_args;
9241 if (explicit_targs == error_mark_node)
9245 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9246 explicit_targs, NULL_TREE, tf_none,
9247 /*require_all_arguments=*/0));
9248 if (converted_args == error_mark_node)
9251 /* Substitute the explicit args into the function type. This is
9252 necessary so that, for instance, explicitly declared function
9253 arguments can match null pointed constants. If we were given
9254 an incomplete set of explicit args, we must not do semantic
9255 processing during substitution as we could create partial
9257 incomplete = NUM_TMPL_ARGS (explicit_targs) != NUM_TMPL_ARGS (targs);
9258 processing_template_decl += incomplete;
9259 fntype = tsubst (fntype, converted_args, tf_none, NULL_TREE);
9260 processing_template_decl -= incomplete;
9262 if (fntype == error_mark_node)
9265 /* Place the explicitly specified arguments in TARGS. */
9266 for (i = NUM_TMPL_ARGS (converted_args); i--;)
9267 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i);
9270 parms = TYPE_ARG_TYPES (fntype);
9271 /* Never do unification on the 'this' parameter. */
9272 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
9273 parms = TREE_CHAIN (parms);
9277 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms);
9278 args = tree_cons (NULL_TREE, return_type, args);
9281 /* We allow incomplete unification without an error message here
9282 because the standard doesn't seem to explicitly prohibit it. Our
9283 callers must be ready to deal with unification failures in any
9285 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn),
9286 targs, parms, args, /*subr=*/0,
9290 /* All is well so far. Now, check:
9294 When all template arguments have been deduced, all uses of
9295 template parameters in nondeduced contexts are replaced with
9296 the corresponding deduced argument values. If the
9297 substitution results in an invalid type, as described above,
9298 type deduction fails. */
9299 if (tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE)
9306 /* Adjust types before performing type deduction, as described in
9307 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two
9308 sections are symmetric. PARM is the type of a function parameter
9309 or the return type of the conversion function. ARG is the type of
9310 the argument passed to the call, or the type of the value
9311 initialized with the result of the conversion function. */
9314 maybe_adjust_types_for_deduction (unification_kind_t strict,
9327 /* Swap PARM and ARG throughout the remainder of this
9328 function; the handling is precisely symmetric since PARM
9329 will initialize ARG rather than vice versa. */
9337 /* There is nothing to do in this case. */
9344 if (TREE_CODE (*parm) != REFERENCE_TYPE)
9346 /* [temp.deduct.call]
9348 If P is not a reference type:
9350 --If A is an array type, the pointer type produced by the
9351 array-to-pointer standard conversion (_conv.array_) is
9352 used in place of A for type deduction; otherwise,
9354 --If A is a function type, the pointer type produced by
9355 the function-to-pointer standard conversion
9356 (_conv.func_) is used in place of A for type deduction;
9359 --If A is a cv-qualified type, the top level
9360 cv-qualifiers of A's type are ignored for type
9362 if (TREE_CODE (*arg) == ARRAY_TYPE)
9363 *arg = build_pointer_type (TREE_TYPE (*arg));
9364 else if (TREE_CODE (*arg) == FUNCTION_TYPE)
9365 *arg = build_pointer_type (*arg);
9367 *arg = TYPE_MAIN_VARIANT (*arg);
9370 /* [temp.deduct.call]
9372 If P is a cv-qualified type, the top level cv-qualifiers
9373 of P's type are ignored for type deduction. If P is a
9374 reference type, the type referred to by P is used for
9376 *parm = TYPE_MAIN_VARIANT (*parm);
9377 if (TREE_CODE (*parm) == REFERENCE_TYPE)
9379 *parm = TREE_TYPE (*parm);
9380 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9383 /* DR 322. For conversion deduction, remove a reference type on parm
9384 too (which has been swapped into ARG). */
9385 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE)
9386 *arg = TREE_TYPE (*arg);
9391 /* Most parms like fn_type_unification.
9393 If SUBR is 1, we're being called recursively (to unify the
9394 arguments of a function or method parameter of a function
9398 type_unification_real (tree tparms,
9403 unification_kind_t strict,
9408 int ntparms = TREE_VEC_LENGTH (tparms);
9410 int saw_undeduced = 0;
9413 gcc_assert (TREE_CODE (tparms) == TREE_VEC);
9414 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST);
9415 gcc_assert (!xargs || TREE_CODE (xargs) == TREE_LIST);
9416 gcc_assert (ntparms > 0);
9421 sub_strict = (UNIFY_ALLOW_OUTER_LEVEL | UNIFY_ALLOW_MORE_CV_QUAL
9422 | UNIFY_ALLOW_DERIVED);
9426 sub_strict = UNIFY_ALLOW_LESS_CV_QUAL;
9430 sub_strict = UNIFY_ALLOW_NONE;
9441 while (parms && parms != void_list_node
9442 && args && args != void_list_node)
9444 parm = TREE_VALUE (parms);
9445 parms = TREE_CHAIN (parms);
9446 arg = TREE_VALUE (args);
9447 args = TREE_CHAIN (args);
9449 if (arg == error_mark_node)
9451 if (arg == unknown_type_node)
9452 /* We can't deduce anything from this, but we might get all the
9453 template args from other function args. */
9456 /* Conversions will be performed on a function argument that
9457 corresponds with a function parameter that contains only
9458 non-deducible template parameters and explicitly specified
9459 template parameters. */
9460 if (!uses_template_parms (parm))
9465 type = TREE_TYPE (arg);
9469 if (same_type_p (parm, type))
9471 if (strict != DEDUCE_EXACT
9472 && can_convert_arg (parm, type, TYPE_P (arg) ? NULL_TREE : arg,
9481 gcc_assert (TREE_TYPE (arg) != NULL_TREE);
9482 if (type_unknown_p (arg))
9484 /* [temp.deduct.type] A template-argument can be deduced from
9485 a pointer to function or pointer to member function
9486 argument if the set of overloaded functions does not
9487 contain function templates and at most one of a set of
9488 overloaded functions provides a unique match. */
9490 if (resolve_overloaded_unification
9491 (tparms, targs, parm, arg, strict, sub_strict)
9496 arg = TREE_TYPE (arg);
9497 if (arg == error_mark_node)
9502 int arg_strict = sub_strict;
9505 arg_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9507 if (unify (tparms, targs, parm, arg, arg_strict))
9512 /* Fail if we've reached the end of the parm list, and more args
9513 are present, and the parm list isn't variadic. */
9514 if (args && args != void_list_node && parms == void_list_node)
9516 /* Fail if parms are left and they don't have default values. */
9517 if (parms && parms != void_list_node
9518 && TREE_PURPOSE (parms) == NULL_TREE)
9522 for (i = 0; i < ntparms; i++)
9523 if (!TREE_VEC_ELT (targs, i))
9525 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i));
9527 /* If this is an undeduced nontype parameter that depends on
9528 a type parameter, try another pass; its type may have been
9529 deduced from a later argument than the one from which
9530 this parameter can be deduced. */
9531 if (TREE_CODE (tparm) == PARM_DECL
9532 && uses_template_parms (TREE_TYPE (tparm))
9533 && !saw_undeduced++)
9542 /* Subroutine of type_unification_real. Args are like the variables at the
9543 call site. ARG is an overloaded function (or template-id); we try
9544 deducing template args from each of the overloads, and if only one
9545 succeeds, we go with that. Modifies TARGS and returns 0 on success. */
9548 resolve_overloaded_unification (tree tparms,
9552 unification_kind_t strict,
9555 tree tempargs = copy_node (targs);
9559 if (TREE_CODE (arg) == ADDR_EXPR)
9561 arg = TREE_OPERAND (arg, 0);
9567 if (TREE_CODE (arg) == COMPONENT_REF)
9568 /* Handle `&x' where `x' is some static or non-static member
9570 arg = TREE_OPERAND (arg, 1);
9572 if (TREE_CODE (arg) == OFFSET_REF)
9573 arg = TREE_OPERAND (arg, 1);
9575 /* Strip baselink information. */
9576 if (BASELINK_P (arg))
9577 arg = BASELINK_FUNCTIONS (arg);
9579 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR)
9581 /* If we got some explicit template args, we need to plug them into
9582 the affected templates before we try to unify, in case the
9583 explicit args will completely resolve the templates in question. */
9585 tree expl_subargs = TREE_OPERAND (arg, 1);
9586 arg = TREE_OPERAND (arg, 0);
9588 for (; arg; arg = OVL_NEXT (arg))
9590 tree fn = OVL_CURRENT (arg);
9593 if (TREE_CODE (fn) != TEMPLATE_DECL)
9596 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn),
9597 expl_subargs, /*check_ret=*/false);
9600 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE);
9601 good += try_one_overload (tparms, targs, tempargs, parm,
9602 elem, strict, sub_strict, addr_p);
9608 gcc_assert (TREE_CODE (arg) == OVERLOAD
9609 || TREE_CODE (arg) == FUNCTION_DECL);
9611 for (; arg; arg = OVL_NEXT (arg))
9612 good += try_one_overload (tparms, targs, tempargs, parm,
9613 TREE_TYPE (OVL_CURRENT (arg)),
9614 strict, sub_strict, addr_p);
9617 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9618 to function or pointer to member function argument if the set of
9619 overloaded functions does not contain function templates and at most
9620 one of a set of overloaded functions provides a unique match.
9622 So if we found multiple possibilities, we return success but don't
9627 int i = TREE_VEC_LENGTH (targs);
9629 if (TREE_VEC_ELT (tempargs, i))
9630 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i);
9638 /* Subroutine of resolve_overloaded_unification; does deduction for a single
9639 overload. Fills TARGS with any deduced arguments, or error_mark_node if
9640 different overloads deduce different arguments for a given parm.
9641 ADDR_P is true if the expression for which deduction is being
9642 performed was of the form "& fn" rather than simply "fn".
9644 Returns 1 on success. */
9647 try_one_overload (tree tparms,
9652 unification_kind_t strict,
9660 /* [temp.deduct.type] A template-argument can be deduced from a pointer
9661 to function or pointer to member function argument if the set of
9662 overloaded functions does not contain function templates and at most
9663 one of a set of overloaded functions provides a unique match.
9665 So if this is a template, just return success. */
9667 if (uses_template_parms (arg))
9670 if (TREE_CODE (arg) == METHOD_TYPE)
9671 arg = build_ptrmemfunc_type (build_pointer_type (arg));
9673 arg = build_pointer_type (arg);
9675 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg);
9677 /* We don't copy orig_targs for this because if we have already deduced
9678 some template args from previous args, unify would complain when we
9679 try to deduce a template parameter for the same argument, even though
9680 there isn't really a conflict. */
9681 nargs = TREE_VEC_LENGTH (targs);
9682 tempargs = make_tree_vec (nargs);
9684 if (unify (tparms, tempargs, parm, arg, sub_strict) != 0)
9687 /* First make sure we didn't deduce anything that conflicts with
9688 explicitly specified args. */
9689 for (i = nargs; i--; )
9691 tree elt = TREE_VEC_ELT (tempargs, i);
9692 tree oldelt = TREE_VEC_ELT (orig_targs, i);
9696 else if (uses_template_parms (elt))
9697 /* Since we're unifying against ourselves, we will fill in
9698 template args used in the function parm list with our own
9699 template parms. Discard them. */
9700 TREE_VEC_ELT (tempargs, i) = NULL_TREE;
9701 else if (oldelt && !template_args_equal (oldelt, elt))
9705 for (i = nargs; i--; )
9707 tree elt = TREE_VEC_ELT (tempargs, i);
9710 TREE_VEC_ELT (targs, i) = elt;
9716 /* Verify that nondeduce template argument agrees with the type
9717 obtained from argument deduction. Return nonzero if the
9722 struct A { typedef int X; };
9723 template <class T, class U> struct C {};
9724 template <class T> struct C<T, typename T::X> {};
9726 Then with the instantiation `C<A, int>', we can deduce that
9727 `T' is `A' but unify () does not check whether `typename T::X'
9728 is `int'. This function ensure that they agree.
9730 TARGS, PARMS are the same as the arguments of unify.
9731 ARGS contains template arguments from all levels. */
9734 verify_class_unification (tree targs, tree parms, tree args)
9736 parms = tsubst (parms, add_outermost_template_args (args, targs),
9737 tf_none, NULL_TREE);
9738 if (parms == error_mark_node)
9741 return !comp_template_args (parms, INNERMOST_TEMPLATE_ARGS (args));
9744 /* PARM is a template class (perhaps with unbound template
9745 parameters). ARG is a fully instantiated type. If ARG can be
9746 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and
9747 TARGS are as for unify. */
9750 try_class_unification (tree tparms, tree targs, tree parm, tree arg)
9754 if (!CLASSTYPE_TEMPLATE_INFO (arg)
9755 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg))
9756 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm))))
9759 /* We need to make a new template argument vector for the call to
9760 unify. If we used TARGS, we'd clutter it up with the result of
9761 the attempted unification, even if this class didn't work out.
9762 We also don't want to commit ourselves to all the unifications
9763 we've already done, since unification is supposed to be done on
9764 an argument-by-argument basis. In other words, consider the
9765 following pathological case:
9767 template <int I, int J, int K>
9770 template <int I, int J>
9771 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {};
9773 template <int I, int J, int K>
9774 void f(S<I, J, K>, S<I, I, I>);
9783 Now, by the time we consider the unification involving `s2', we
9784 already know that we must have `f<0, 0, 0>'. But, even though
9785 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid
9786 because there are two ways to unify base classes of S<0, 1, 2>
9787 with S<I, I, I>. If we kept the already deduced knowledge, we
9788 would reject the possibility I=1. */
9789 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs));
9791 /* If unification failed, we're done. */
9792 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm),
9793 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE))
9799 /* Given a template type PARM and a class type ARG, find the unique
9800 base type in ARG that is an instance of PARM. We do not examine
9801 ARG itself; only its base-classes. If there is not exactly one
9802 appropriate base class, return NULL_TREE. PARM may be the type of
9803 a partial specialization, as well as a plain template type. Used
9807 get_template_base (tree tparms, tree targs, tree parm, tree arg)
9809 tree rval = NULL_TREE;
9812 gcc_assert (IS_AGGR_TYPE_CODE (TREE_CODE (arg)));
9814 binfo = TYPE_BINFO (complete_type (arg));
9816 /* The type could not be completed. */
9819 /* Walk in inheritance graph order. The search order is not
9820 important, and this avoids multiple walks of virtual bases. */
9821 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo))
9823 tree r = try_class_unification (tparms, targs, parm, BINFO_TYPE (binfo));
9827 /* If there is more than one satisfactory baseclass, then:
9831 If they yield more than one possible deduced A, the type
9835 if (rval && !same_type_p (r, rval))
9845 /* Returns the level of DECL, which declares a template parameter. */
9848 template_decl_level (tree decl)
9850 switch (TREE_CODE (decl))
9854 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl));
9857 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl));
9865 /* Decide whether ARG can be unified with PARM, considering only the
9866 cv-qualifiers of each type, given STRICT as documented for unify.
9867 Returns nonzero iff the unification is OK on that basis. */
9870 check_cv_quals_for_unify (int strict, tree arg, tree parm)
9872 int arg_quals = cp_type_quals (arg);
9873 int parm_quals = cp_type_quals (parm);
9875 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM
9876 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9878 /* Although a CVR qualifier is ignored when being applied to a
9879 substituted template parameter ([8.3.2]/1 for example), that
9880 does not apply during deduction [14.8.2.4]/1, (even though
9881 that is not explicitly mentioned, [14.8.2.4]/9 indicates
9882 this). Except when we're allowing additional CV qualifiers
9883 at the outer level [14.8.2.1]/3,1st bullet. */
9884 if ((TREE_CODE (arg) == REFERENCE_TYPE
9885 || TREE_CODE (arg) == FUNCTION_TYPE
9886 || TREE_CODE (arg) == METHOD_TYPE)
9887 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE)))
9890 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM)
9891 && (parm_quals & TYPE_QUAL_RESTRICT))
9895 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL))
9896 && (arg_quals & parm_quals) != parm_quals)
9899 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL))
9900 && (parm_quals & arg_quals) != arg_quals)
9906 /* Takes parameters as for type_unification. Returns 0 if the
9907 type deduction succeeds, 1 otherwise. The parameter STRICT is a
9908 bitwise or of the following flags:
9911 Require an exact match between PARM and ARG.
9912 UNIFY_ALLOW_MORE_CV_QUAL:
9913 Allow the deduced ARG to be more cv-qualified (by qualification
9914 conversion) than ARG.
9915 UNIFY_ALLOW_LESS_CV_QUAL:
9916 Allow the deduced ARG to be less cv-qualified than ARG.
9917 UNIFY_ALLOW_DERIVED:
9918 Allow the deduced ARG to be a template base class of ARG,
9919 or a pointer to a template base class of the type pointed to by
9921 UNIFY_ALLOW_INTEGER:
9922 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX
9923 case for more information.
9924 UNIFY_ALLOW_OUTER_LEVEL:
9925 This is the outermost level of a deduction. Used to determine validity
9926 of qualification conversions. A valid qualification conversion must
9927 have const qualified pointers leading up to the inner type which
9928 requires additional CV quals, except at the outer level, where const
9929 is not required [conv.qual]. It would be normal to set this flag in
9930 addition to setting UNIFY_ALLOW_MORE_CV_QUAL.
9931 UNIFY_ALLOW_OUTER_MORE_CV_QUAL:
9932 This is the outermost level of a deduction, and PARM can be more CV
9933 qualified at this point.
9934 UNIFY_ALLOW_OUTER_LESS_CV_QUAL:
9935 This is the outermost level of a deduction, and PARM can be less CV
9936 qualified at this point. */
9939 unify (tree tparms, tree targs, tree parm, tree arg, int strict)
9944 int strict_in = strict;
9946 /* I don't think this will do the right thing with respect to types.
9947 But the only case I've seen it in so far has been array bounds, where
9948 signedness is the only information lost, and I think that will be
9950 while (TREE_CODE (parm) == NOP_EXPR)
9951 parm = TREE_OPERAND (parm, 0);
9953 if (arg == error_mark_node)
9955 if (arg == unknown_type_node)
9956 /* We can't deduce anything from this, but we might get all the
9957 template args from other function args. */
9960 /* If PARM uses template parameters, then we can't bail out here,
9961 even if ARG == PARM, since we won't record unifications for the
9962 template parameters. We might need them if we're trying to
9963 figure out which of two things is more specialized. */
9964 if (arg == parm && !uses_template_parms (parm))
9967 /* Immediately reject some pairs that won't unify because of
9968 cv-qualification mismatches. */
9969 if (TREE_CODE (arg) == TREE_CODE (parm)
9971 /* It is the elements of the array which hold the cv quals of an array
9972 type, and the elements might be template type parms. We'll check
9974 && TREE_CODE (arg) != ARRAY_TYPE
9975 /* We check the cv-qualifiers when unifying with template type
9976 parameters below. We want to allow ARG `const T' to unify with
9977 PARM `T' for example, when computing which of two templates
9978 is more specialized, for example. */
9979 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM
9980 && !check_cv_quals_for_unify (strict_in, arg, parm))
9983 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL)
9984 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm))
9985 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL;
9986 strict &= ~UNIFY_ALLOW_OUTER_LEVEL;
9987 strict &= ~UNIFY_ALLOW_DERIVED;
9988 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL;
9989 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL;
9991 switch (TREE_CODE (parm))
9995 case UNBOUND_CLASS_TEMPLATE:
9996 /* In a type which contains a nested-name-specifier, template
9997 argument values cannot be deduced for template parameters used
9998 within the nested-name-specifier. */
10001 case TEMPLATE_TYPE_PARM:
10002 case TEMPLATE_TEMPLATE_PARM:
10003 case BOUND_TEMPLATE_TEMPLATE_PARM:
10004 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10006 if (TEMPLATE_TYPE_LEVEL (parm)
10007 != template_decl_level (tparm))
10008 /* The PARM is not one we're trying to unify. Just check
10009 to see if it matches ARG. */
10010 return (TREE_CODE (arg) == TREE_CODE (parm)
10011 && same_type_p (parm, arg)) ? 0 : 1;
10012 idx = TEMPLATE_TYPE_IDX (parm);
10013 targ = TREE_VEC_ELT (targs, idx);
10014 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx));
10016 /* Check for mixed types and values. */
10017 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM
10018 && TREE_CODE (tparm) != TYPE_DECL)
10019 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10020 && TREE_CODE (tparm) != TEMPLATE_DECL))
10023 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10025 /* ARG must be constructed from a template class or a template
10026 template parameter. */
10027 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM
10028 && (TREE_CODE (arg) != RECORD_TYPE || !CLASSTYPE_TEMPLATE_INFO (arg)))
10032 tree parmtmpl = TYPE_TI_TEMPLATE (parm);
10033 tree parmvec = TYPE_TI_ARGS (parm);
10034 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg));
10036 = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_TI_TEMPLATE (arg));
10039 /* The parameter and argument roles have to be switched here
10040 in order to handle default arguments properly. For example,
10041 template<template <class> class TT> void f(TT<int>)
10042 should be able to accept vector<int> which comes from
10043 template <class T, class Allocator = allocator>
10046 if (coerce_template_parms (argtmplvec, parmvec, parmtmpl, 0, 1)
10047 == error_mark_node)
10050 /* Deduce arguments T, i from TT<T> or TT<i>.
10051 We check each element of PARMVEC and ARGVEC individually
10052 rather than the whole TREE_VEC since they can have
10053 different number of elements. */
10055 for (i = 0; i < TREE_VEC_LENGTH (parmvec); ++i)
10057 if (unify (tparms, targs,
10058 TREE_VEC_ELT (parmvec, i),
10059 TREE_VEC_ELT (argvec, i),
10064 arg = TYPE_TI_TEMPLATE (arg);
10066 /* Fall through to deduce template name. */
10069 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM
10070 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM)
10072 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */
10074 /* Simple cases: Value already set, does match or doesn't. */
10075 if (targ != NULL_TREE && template_args_equal (targ, arg))
10082 /* If PARM is `const T' and ARG is only `int', we don't have
10083 a match unless we are allowing additional qualification.
10084 If ARG is `const int' and PARM is just `T' that's OK;
10085 that binds `const int' to `T'. */
10086 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL,
10090 /* Consider the case where ARG is `const volatile int' and
10091 PARM is `const T'. Then, T should be `volatile int'. */
10092 arg = cp_build_qualified_type_real
10093 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none);
10094 if (arg == error_mark_node)
10097 /* Simple cases: Value already set, does match or doesn't. */
10098 if (targ != NULL_TREE && same_type_p (targ, arg))
10103 /* Make sure that ARG is not a variable-sized array. (Note
10104 that were talking about variable-sized arrays (like
10105 `int[n]'), rather than arrays of unknown size (like
10106 `int[]').) We'll get very confused by such a type since
10107 the bound of the array will not be computable in an
10108 instantiation. Besides, such types are not allowed in
10109 ISO C++, so we can do as we please here. */
10110 if (variably_modified_type_p (arg, NULL_TREE))
10114 TREE_VEC_ELT (targs, idx) = arg;
10117 case TEMPLATE_PARM_INDEX:
10118 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0));
10120 if (TEMPLATE_PARM_LEVEL (parm)
10121 != template_decl_level (tparm))
10122 /* The PARM is not one we're trying to unify. Just check
10123 to see if it matches ARG. */
10124 return !(TREE_CODE (arg) == TREE_CODE (parm)
10125 && cp_tree_equal (parm, arg));
10127 idx = TEMPLATE_PARM_IDX (parm);
10128 targ = TREE_VEC_ELT (targs, idx);
10131 return !cp_tree_equal (targ, arg);
10133 /* [temp.deduct.type] If, in the declaration of a function template
10134 with a non-type template-parameter, the non-type
10135 template-parameter is used in an expression in the function
10136 parameter-list and, if the corresponding template-argument is
10137 deduced, the template-argument type shall match the type of the
10138 template-parameter exactly, except that a template-argument
10139 deduced from an array bound may be of any integral type.
10140 The non-type parameter might use already deduced type parameters. */
10141 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE);
10142 if (!TREE_TYPE (arg))
10143 /* Template-parameter dependent expression. Just accept it for now.
10144 It will later be processed in convert_template_argument. */
10146 else if (same_type_p (TREE_TYPE (arg), tparm))
10148 else if ((strict & UNIFY_ALLOW_INTEGER)
10149 && (TREE_CODE (tparm) == INTEGER_TYPE
10150 || TREE_CODE (tparm) == BOOLEAN_TYPE))
10151 /* Convert the ARG to the type of PARM; the deduced non-type
10152 template argument must exactly match the types of the
10153 corresponding parameter. */
10154 arg = fold (build_nop (TREE_TYPE (parm), arg));
10155 else if (uses_template_parms (tparm))
10156 /* We haven't deduced the type of this parameter yet. Try again
10162 TREE_VEC_ELT (targs, idx) = arg;
10167 /* A pointer-to-member constant can be unified only with
10168 another constant. */
10169 if (TREE_CODE (arg) != PTRMEM_CST)
10172 /* Just unify the class member. It would be useless (and possibly
10173 wrong, depending on the strict flags) to unify also
10174 PTRMEM_CST_CLASS, because we want to be sure that both parm and
10175 arg refer to the same variable, even if through different
10176 classes. For instance:
10178 struct A { int x; };
10181 Unification of &A::x and &B::x must succeed. */
10182 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm),
10183 PTRMEM_CST_MEMBER (arg), strict);
10188 if (TREE_CODE (arg) != POINTER_TYPE)
10191 /* [temp.deduct.call]
10193 A can be another pointer or pointer to member type that can
10194 be converted to the deduced A via a qualification
10195 conversion (_conv.qual_).
10197 We pass down STRICT here rather than UNIFY_ALLOW_NONE.
10198 This will allow for additional cv-qualification of the
10199 pointed-to types if appropriate. */
10201 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE)
10202 /* The derived-to-base conversion only persists through one
10203 level of pointers. */
10204 strict |= (strict_in & UNIFY_ALLOW_DERIVED);
10206 return unify (tparms, targs, TREE_TYPE (parm),
10207 TREE_TYPE (arg), strict);
10210 case REFERENCE_TYPE:
10211 if (TREE_CODE (arg) != REFERENCE_TYPE)
10213 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10214 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10217 if (TREE_CODE (arg) != ARRAY_TYPE)
10219 if ((TYPE_DOMAIN (parm) == NULL_TREE)
10220 != (TYPE_DOMAIN (arg) == NULL_TREE))
10222 if (TYPE_DOMAIN (parm) != NULL_TREE)
10227 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm));
10228 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg));
10230 /* Our representation of array types uses "N - 1" as the
10231 TYPE_MAX_VALUE for an array with "N" elements, if "N" is
10232 not an integer constant. */
10233 if (TREE_CODE (parm_max) == MINUS_EXPR)
10235 arg_max = fold_build2 (PLUS_EXPR,
10238 TREE_OPERAND (parm_max, 1));
10239 parm_max = TREE_OPERAND (parm_max, 0);
10242 if (unify (tparms, targs, parm_max, arg_max, UNIFY_ALLOW_INTEGER))
10245 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10246 strict & UNIFY_ALLOW_MORE_CV_QUAL);
10253 case ENUMERAL_TYPE:
10255 if (TREE_CODE (arg) != TREE_CODE (parm))
10258 /* We have already checked cv-qualification at the top of the
10260 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm))
10263 /* As far as unification is concerned, this wins. Later checks
10264 will invalidate it if necessary. */
10267 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */
10268 /* Type INTEGER_CST can come from ordinary constant template args. */
10270 while (TREE_CODE (arg) == NOP_EXPR)
10271 arg = TREE_OPERAND (arg, 0);
10273 if (TREE_CODE (arg) != INTEGER_CST)
10275 return !tree_int_cst_equal (parm, arg);
10280 if (TREE_CODE (arg) != TREE_VEC)
10282 if (TREE_VEC_LENGTH (parm) != TREE_VEC_LENGTH (arg))
10284 for (i = 0; i < TREE_VEC_LENGTH (parm); ++i)
10285 if (unify (tparms, targs,
10286 TREE_VEC_ELT (parm, i), TREE_VEC_ELT (arg, i),
10294 if (TREE_CODE (arg) != TREE_CODE (parm))
10297 if (TYPE_PTRMEMFUNC_P (parm))
10299 if (!TYPE_PTRMEMFUNC_P (arg))
10302 return unify (tparms, targs,
10303 TYPE_PTRMEMFUNC_FN_TYPE (parm),
10304 TYPE_PTRMEMFUNC_FN_TYPE (arg),
10308 if (CLASSTYPE_TEMPLATE_INFO (parm))
10310 tree t = NULL_TREE;
10312 if (strict_in & UNIFY_ALLOW_DERIVED)
10314 /* First, we try to unify the PARM and ARG directly. */
10315 t = try_class_unification (tparms, targs,
10320 /* Fallback to the special case allowed in
10321 [temp.deduct.call]:
10323 If P is a class, and P has the form
10324 template-id, then A can be a derived class of
10325 the deduced A. Likewise, if P is a pointer to
10326 a class of the form template-id, A can be a
10327 pointer to a derived class pointed to by the
10329 t = get_template_base (tparms, targs, parm, arg);
10335 else if (CLASSTYPE_TEMPLATE_INFO (arg)
10336 && (CLASSTYPE_TI_TEMPLATE (parm)
10337 == CLASSTYPE_TI_TEMPLATE (arg)))
10338 /* Perhaps PARM is something like S<U> and ARG is S<int>.
10339 Then, we should unify `int' and `U'. */
10342 /* There's no chance of unification succeeding. */
10345 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm),
10346 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE);
10348 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg))
10353 case FUNCTION_TYPE:
10354 if (TREE_CODE (arg) != TREE_CODE (parm))
10357 /* CV qualifications for methods can never be deduced, they must
10358 match exactly. We need to check them explicitly here,
10359 because type_unification_real treats them as any other
10360 cvqualified parameter. */
10361 if (TREE_CODE (parm) == METHOD_TYPE
10362 && (!check_cv_quals_for_unify
10364 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (arg))),
10365 TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (parm))))))
10368 if (unify (tparms, targs, TREE_TYPE (parm),
10369 TREE_TYPE (arg), UNIFY_ALLOW_NONE))
10371 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm),
10372 TYPE_ARG_TYPES (arg), 1, DEDUCE_EXACT,
10376 /* Unify a pointer to member with a pointer to member function, which
10377 deduces the type of the member as a function type. */
10378 if (TYPE_PTRMEMFUNC_P (arg))
10382 cp_cv_quals cv_quals;
10384 /* Check top-level cv qualifiers */
10385 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm))
10388 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10389 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), UNIFY_ALLOW_NONE))
10392 /* Determine the type of the function we are unifying against. */
10393 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg));
10395 build_function_type (TREE_TYPE (method_type),
10396 TREE_CHAIN (TYPE_ARG_TYPES (method_type)));
10398 /* Extract the cv-qualifiers of the member function from the
10399 implicit object parameter and place them on the function
10400 type to be restored later. */
10402 cp_type_quals(TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (method_type))));
10403 fntype = build_qualified_type (fntype, cv_quals);
10404 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict);
10407 if (TREE_CODE (arg) != OFFSET_TYPE)
10409 if (unify (tparms, targs, TYPE_OFFSET_BASETYPE (parm),
10410 TYPE_OFFSET_BASETYPE (arg), UNIFY_ALLOW_NONE))
10412 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg),
10416 if (DECL_TEMPLATE_PARM_P (parm))
10417 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict);
10418 if (arg != integral_constant_value (parm))
10423 case TEMPLATE_DECL:
10424 /* Matched cases are handled by the ARG == PARM test above. */
10428 gcc_assert (EXPR_P (parm));
10430 /* We must be looking at an expression. This can happen with
10434 void foo(S<I>, S<I + 2>);
10436 This is a "nondeduced context":
10440 The nondeduced contexts are:
10442 --A type that is a template-id in which one or more of
10443 the template-arguments is an expression that references
10444 a template-parameter.
10446 In these cases, we assume deduction succeeded, but don't
10447 actually infer any unifications. */
10449 if (!uses_template_parms (parm)
10450 && !template_args_equal (parm, arg))
10457 /* Note that DECL can be defined in this translation unit, if
10461 mark_definable (tree decl)
10464 DECL_NOT_REALLY_EXTERN (decl) = 1;
10465 FOR_EACH_CLONE (clone, decl)
10466 DECL_NOT_REALLY_EXTERN (clone) = 1;
10469 /* Called if RESULT is explicitly instantiated, or is a member of an
10470 explicitly instantiated class. */
10473 mark_decl_instantiated (tree result, int extern_p)
10475 SET_DECL_EXPLICIT_INSTANTIATION (result);
10477 /* If this entity has already been written out, it's too late to
10478 make any modifications. */
10479 if (TREE_ASM_WRITTEN (result))
10482 if (TREE_CODE (result) != FUNCTION_DECL)
10483 /* The TREE_PUBLIC flag for function declarations will have been
10484 set correctly by tsubst. */
10485 TREE_PUBLIC (result) = 1;
10487 /* This might have been set by an earlier implicit instantiation. */
10488 DECL_COMDAT (result) = 0;
10491 DECL_NOT_REALLY_EXTERN (result) = 0;
10494 mark_definable (result);
10495 /* Always make artificials weak. */
10496 if (DECL_ARTIFICIAL (result) && flag_weak)
10497 comdat_linkage (result);
10498 /* For WIN32 we also want to put explicit instantiations in
10499 linkonce sections. */
10500 else if (TREE_PUBLIC (result))
10501 maybe_make_one_only (result);
10504 /* If EXTERN_P, then this function will not be emitted -- unless
10505 followed by an explicit instantiation, at which point its linkage
10506 will be adjusted. If !EXTERN_P, then this function will be
10507 emitted here. In neither circumstance do we want
10508 import_export_decl to adjust the linkage. */
10509 DECL_INTERFACE_KNOWN (result) = 1;
10512 /* Given two function templates PAT1 and PAT2, return:
10514 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order].
10515 -1 if PAT2 is more specialized than PAT1.
10516 0 if neither is more specialized.
10518 LEN indicates the number of parameters we should consider
10519 (defaulted parameters should not be considered).
10521 The 1998 std underspecified function template partial ordering, and
10522 DR214 addresses the issue. We take pairs of arguments, one from
10523 each of the templates, and deduce them against each other. One of
10524 the templates will be more specialized if all the *other*
10525 template's arguments deduce against its arguments and at least one
10526 of its arguments *does* *not* deduce against the other template's
10527 corresponding argument. Deduction is done as for class templates.
10528 The arguments used in deduction have reference and top level cv
10529 qualifiers removed. Iff both arguments were originally reference
10530 types *and* deduction succeeds in both directions, the template
10531 with the more cv-qualified argument wins for that pairing (if
10532 neither is more cv-qualified, they both are equal). Unlike regular
10533 deduction, after all the arguments have been deduced in this way,
10534 we do *not* verify the deduced template argument values can be
10535 substituted into non-deduced contexts, nor do we have to verify
10536 that all template arguments have been deduced. */
10539 more_specialized_fn (tree pat1, tree pat2, int len)
10541 tree decl1 = DECL_TEMPLATE_RESULT (pat1);
10542 tree decl2 = DECL_TEMPLATE_RESULT (pat2);
10543 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1));
10544 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2));
10545 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1);
10546 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2);
10547 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1));
10548 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2));
10552 /* Remove the this parameter from non-static member functions. If
10553 one is a non-static member function and the other is not a static
10554 member function, remove the first parameter from that function
10555 also. This situation occurs for operator functions where we
10556 locate both a member function (with this pointer) and non-member
10557 operator (with explicit first operand). */
10558 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1))
10560 len--; /* LEN is the number of significant arguments for DECL1 */
10561 args1 = TREE_CHAIN (args1);
10562 if (!DECL_STATIC_FUNCTION_P (decl2))
10563 args2 = TREE_CHAIN (args2);
10565 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2))
10567 args2 = TREE_CHAIN (args2);
10568 if (!DECL_STATIC_FUNCTION_P (decl1))
10571 args1 = TREE_CHAIN (args1);
10575 /* If only one is a conversion operator, they are unordered. */
10576 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2))
10579 /* Consider the return type for a conversion function */
10580 if (DECL_CONV_FN_P (decl1))
10582 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1);
10583 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2);
10587 processing_template_decl++;
10591 tree arg1 = TREE_VALUE (args1);
10592 tree arg2 = TREE_VALUE (args2);
10593 int deduce1, deduce2;
10597 if (TREE_CODE (arg1) == REFERENCE_TYPE)
10599 arg1 = TREE_TYPE (arg1);
10600 quals1 = cp_type_quals (arg1);
10603 if (TREE_CODE (arg2) == REFERENCE_TYPE)
10605 arg2 = TREE_TYPE (arg2);
10606 quals2 = cp_type_quals (arg2);
10609 if ((quals1 < 0) != (quals2 < 0))
10611 /* Only of the args is a reference, see if we should apply
10612 array/function pointer decay to it. This is not part of
10613 DR214, but is, IMHO, consistent with the deduction rules
10614 for the function call itself, and with our earlier
10615 implementation of the underspecified partial ordering
10616 rules. (nathan). */
10619 switch (TREE_CODE (arg1))
10622 arg1 = TREE_TYPE (arg1);
10624 case FUNCTION_TYPE:
10625 arg1 = build_pointer_type (arg1);
10634 switch (TREE_CODE (arg2))
10637 arg2 = TREE_TYPE (arg2);
10639 case FUNCTION_TYPE:
10640 arg2 = build_pointer_type (arg2);
10649 arg1 = TYPE_MAIN_VARIANT (arg1);
10650 arg2 = TYPE_MAIN_VARIANT (arg2);
10652 deduce1 = !unify (tparms1, targs1, arg1, arg2, UNIFY_ALLOW_NONE);
10653 deduce2 = !unify (tparms2, targs2, arg2, arg1, UNIFY_ALLOW_NONE);
10659 if (better1 < 0 && better2 < 0)
10660 /* We've failed to deduce something in either direction.
10661 These must be unordered. */
10664 if (deduce1 && deduce2 && quals1 >= 0 && quals2 >= 0)
10666 /* Deduces in both directions, see if quals can
10667 disambiguate. Pretend the worse one failed to deduce. */
10668 if ((quals1 & quals2) == quals2)
10670 if ((quals1 & quals2) == quals1)
10673 if (deduce1 && !deduce2 && !better2)
10675 if (deduce2 && !deduce1 && !better1)
10678 args1 = TREE_CHAIN (args1);
10679 args2 = TREE_CHAIN (args2);
10682 processing_template_decl--;
10684 return (better1 > 0) - (better2 > 0);
10687 /* Given two class template specialization list nodes PAT1 and PAT2, return:
10689 1 if PAT1 is more specialized than PAT2 as described in [temp.class.order].
10690 -1 if PAT2 is more specialized than PAT1.
10691 0 if neither is more specialized.
10693 FULL_ARGS is the full set of template arguments that triggers this
10694 partial ordering. */
10697 more_specialized_class (tree pat1, tree pat2, tree full_args)
10702 /* Just like what happens for functions, if we are ordering between
10703 different class template specializations, we may encounter dependent
10704 types in the arguments, and we need our dependency check functions
10705 to behave correctly. */
10706 ++processing_template_decl;
10707 targs = get_class_bindings (TREE_VALUE (pat1), TREE_PURPOSE (pat1),
10708 add_outermost_template_args (full_args, TREE_PURPOSE (pat2)));
10712 targs = get_class_bindings (TREE_VALUE (pat2), TREE_PURPOSE (pat2),
10713 add_outermost_template_args (full_args, TREE_PURPOSE (pat1)));
10716 --processing_template_decl;
10721 /* Return the template arguments that will produce the function signature
10722 DECL from the function template FN, with the explicit template
10723 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must
10724 also match. Return NULL_TREE if no satisfactory arguments could be
10728 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype)
10730 int ntparms = DECL_NTPARMS (fn);
10731 tree targs = make_tree_vec (ntparms);
10733 tree decl_arg_types;
10735 /* Substitute the explicit template arguments into the type of DECL.
10736 The call to fn_type_unification will handle substitution into the
10738 decl_type = TREE_TYPE (decl);
10739 if (explicit_args && uses_template_parms (decl_type))
10742 tree converted_args;
10744 if (DECL_TEMPLATE_INFO (decl))
10745 tmpl = DECL_TI_TEMPLATE (decl);
10747 /* We can get here for some invalid specializations. */
10751 = (coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl),
10752 explicit_args, NULL_TREE,
10753 tf_none, /*require_all_arguments=*/0));
10754 if (converted_args == error_mark_node)
10757 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE);
10758 if (decl_type == error_mark_node)
10762 decl_arg_types = TYPE_ARG_TYPES (decl_type);
10763 /* Never do unification on the 'this' parameter. */
10764 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
10765 decl_arg_types = TREE_CHAIN (decl_arg_types);
10767 if (fn_type_unification (fn, explicit_args, targs,
10769 (check_rettype || DECL_CONV_FN_P (fn)
10770 ? TREE_TYPE (decl_type) : NULL_TREE),
10771 DEDUCE_EXACT, LOOKUP_NORMAL))
10777 /* Return the innermost template arguments that, when applied to a
10778 template specialization whose innermost template parameters are
10779 TPARMS, and whose specialization arguments are PARMS, yield the
10782 For example, suppose we have:
10784 template <class T, class U> struct S {};
10785 template <class T> struct S<T*, int> {};
10787 Then, suppose we want to get `S<double*, int>'. The TPARMS will be
10788 {T}, the PARMS will be {T*, int} and the ARGS will be {double*,
10789 int}. The resulting vector will be {double}, indicating that `T'
10790 is bound to `double'. */
10793 get_class_bindings (tree tparms, tree parms, tree args)
10795 int i, ntparms = TREE_VEC_LENGTH (tparms);
10796 tree vec = make_tree_vec (ntparms);
10798 if (unify (tparms, vec, parms, INNERMOST_TEMPLATE_ARGS (args),
10802 for (i = 0; i < ntparms; ++i)
10803 if (! TREE_VEC_ELT (vec, i))
10806 if (verify_class_unification (vec, parms, args))
10812 /* In INSTANTIATIONS is a list of <INSTANTIATION, TEMPLATE> pairs.
10813 Pick the most specialized template, and return the corresponding
10814 instantiation, or if there is no corresponding instantiation, the
10815 template itself. If there is no most specialized template,
10816 error_mark_node is returned. If there are no templates at all,
10817 NULL_TREE is returned. */
10820 most_specialized_instantiation (tree instantiations)
10824 if (!instantiations)
10827 ++processing_template_decl;
10829 champ = instantiations;
10830 for (fn = TREE_CHAIN (instantiations); fn; fn = TREE_CHAIN (fn))
10834 if (get_bindings (TREE_VALUE (champ),
10835 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10836 NULL_TREE, /*check_ret=*/false))
10839 if (get_bindings (TREE_VALUE (fn),
10840 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10841 NULL_TREE, /*check_ret=*/false))
10848 /* Equally specialized, move to next function. If there
10849 is no next function, nothing's most specialized. */
10850 fn = TREE_CHAIN (fn);
10857 /* Now verify that champ is better than everything earlier in the
10858 instantiation list. */
10859 for (fn = instantiations; fn != champ; fn = TREE_CHAIN (fn))
10860 if (get_bindings (TREE_VALUE (champ),
10861 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)),
10862 NULL_TREE, /*check_ret=*/false)
10863 || !get_bindings (TREE_VALUE (fn),
10864 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)),
10865 NULL_TREE, /*check_ret=*/false))
10871 processing_template_decl--;
10874 return error_mark_node;
10876 return TREE_PURPOSE (champ) ? TREE_PURPOSE (champ) : TREE_VALUE (champ);
10879 /* Return the most specialized of the list of templates in FNS that can
10880 produce an instantiation matching DECL, given the explicit template
10881 arguments EXPLICIT_ARGS. */
10884 most_specialized (tree fns, tree decl, tree explicit_args)
10886 tree candidates = NULL_TREE;
10889 for (fn = fns; fn; fn = TREE_CHAIN (fn))
10891 tree candidate = TREE_VALUE (fn);
10893 args = get_bindings (candidate, decl, explicit_args, /*check_ret=*/true);
10895 candidates = tree_cons (NULL_TREE, candidate, candidates);
10898 return most_specialized_instantiation (candidates);
10901 /* If DECL is a specialization of some template, return the most
10902 general such template. Otherwise, returns NULL_TREE.
10904 For example, given:
10906 template <class T> struct S { template <class U> void f(U); };
10908 if TMPL is `template <class U> void S<int>::f(U)' this will return
10909 the full template. This function will not trace past partial
10910 specializations, however. For example, given in addition:
10912 template <class T> struct S<T*> { template <class U> void f(U); };
10914 if TMPL is `template <class U> void S<int*>::f(U)' this will return
10915 `template <class T> template <class U> S<T*>::f(U)'. */
10918 most_general_template (tree decl)
10920 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is
10921 an immediate specialization. */
10922 if (TREE_CODE (decl) == FUNCTION_DECL)
10924 if (DECL_TEMPLATE_INFO (decl)) {
10925 decl = DECL_TI_TEMPLATE (decl);
10927 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a
10928 template friend. */
10929 if (TREE_CODE (decl) != TEMPLATE_DECL)
10935 /* Look for more and more general templates. */
10936 while (DECL_TEMPLATE_INFO (decl))
10938 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases.
10939 (See cp-tree.h for details.) */
10940 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL)
10943 if (CLASS_TYPE_P (TREE_TYPE (decl))
10944 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl)))
10947 /* Stop if we run into an explicitly specialized class template. */
10948 if (!DECL_NAMESPACE_SCOPE_P (decl)
10949 && DECL_CONTEXT (decl)
10950 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl)))
10953 decl = DECL_TI_TEMPLATE (decl);
10959 /* Return the most specialized of the class template specializations
10960 of TMPL which can produce an instantiation matching ARGS, or
10961 error_mark_node if the choice is ambiguous. */
10964 most_specialized_class (tree tmpl, tree args)
10966 tree list = NULL_TREE;
10971 tmpl = most_general_template (tmpl);
10972 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t))
10975 = get_class_bindings (TREE_VALUE (t), TREE_PURPOSE (t), args);
10978 list = tree_cons (TREE_PURPOSE (t), TREE_VALUE (t), list);
10979 TREE_TYPE (list) = TREE_TYPE (t);
10988 t = TREE_CHAIN (t);
10989 for (; t; t = TREE_CHAIN (t))
10991 fate = more_specialized_class (champ, t, args);
10998 t = TREE_CHAIN (t);
11000 return error_mark_node;
11006 for (t = list; t && t != champ; t = TREE_CHAIN (t))
11008 fate = more_specialized_class (champ, t, args);
11010 return error_mark_node;
11016 /* Explicitly instantiate DECL. */
11019 do_decl_instantiation (tree decl, tree storage)
11021 tree result = NULL_TREE;
11025 /* An error occurred, for which grokdeclarator has already issued
11026 an appropriate message. */
11028 else if (! DECL_LANG_SPECIFIC (decl))
11030 error ("explicit instantiation of non-template %q#D", decl);
11033 else if (TREE_CODE (decl) == VAR_DECL)
11035 /* There is an asymmetry here in the way VAR_DECLs and
11036 FUNCTION_DECLs are handled by grokdeclarator. In the case of
11037 the latter, the DECL we get back will be marked as a
11038 template instantiation, and the appropriate
11039 DECL_TEMPLATE_INFO will be set up. This does not happen for
11040 VAR_DECLs so we do the lookup here. Probably, grokdeclarator
11041 should handle VAR_DECLs as it currently handles
11043 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false);
11044 if (!result || TREE_CODE (result) != VAR_DECL)
11046 error ("no matching template for %qD found", decl);
11050 else if (TREE_CODE (decl) != FUNCTION_DECL)
11052 error ("explicit instantiation of %q#D", decl);
11058 /* Check for various error cases. Note that if the explicit
11059 instantiation is valid the RESULT will currently be marked as an
11060 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set
11061 until we get here. */
11063 if (DECL_TEMPLATE_SPECIALIZATION (result))
11065 /* DR 259 [temp.spec].
11067 Both an explicit instantiation and a declaration of an explicit
11068 specialization shall not appear in a program unless the explicit
11069 instantiation follows a declaration of the explicit specialization.
11071 For a given set of template parameters, if an explicit
11072 instantiation of a template appears after a declaration of an
11073 explicit specialization for that template, the explicit
11074 instantiation has no effect. */
11077 else if (DECL_EXPLICIT_INSTANTIATION (result))
11081 No program shall explicitly instantiate any template more
11084 We check DECL_NOT_REALLY_EXTERN so as not to complain when
11085 the first instantiation was `extern' and the second is not,
11086 and EXTERN_P for the opposite case. */
11087 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p)
11088 pedwarn ("duplicate explicit instantiation of %q#D", result);
11089 /* If an "extern" explicit instantiation follows an ordinary
11090 explicit instantiation, the template is instantiated. */
11094 else if (!DECL_IMPLICIT_INSTANTIATION (result))
11096 error ("no matching template for %qD found", result);
11099 else if (!DECL_TEMPLATE_INFO (result))
11101 pedwarn ("explicit instantiation of non-template %q#D", result);
11105 if (storage == NULL_TREE)
11107 else if (storage == ridpointers[(int) RID_EXTERN])
11109 if (pedantic && !in_system_header)
11110 pedwarn ("ISO C++ forbids the use of %<extern%> on explicit "
11115 error ("storage class %qD applied to template instantiation", storage);
11117 check_explicit_instantiation_namespace (result);
11118 mark_decl_instantiated (result, extern_p);
11120 instantiate_decl (result, /*defer_ok=*/1,
11121 /*expl_inst_class_mem_p=*/false);
11125 mark_class_instantiated (tree t, int extern_p)
11127 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t);
11128 SET_CLASSTYPE_INTERFACE_KNOWN (t);
11129 CLASSTYPE_INTERFACE_ONLY (t) = extern_p;
11130 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p;
11133 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
11134 rest_of_type_compilation (t, 1);
11138 /* Called from do_type_instantiation through binding_table_foreach to
11139 do recursive instantiation for the type bound in ENTRY. */
11141 bt_instantiate_type_proc (binding_entry entry, void *data)
11143 tree storage = *(tree *) data;
11145 if (IS_AGGR_TYPE (entry->type)
11146 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type)))
11147 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0);
11150 /* Called from do_type_instantiation to instantiate a member
11151 (a member function or a static member variable) of an
11152 explicitly instantiated class template. */
11154 instantiate_class_member (tree decl, int extern_p)
11156 mark_decl_instantiated (decl, extern_p);
11158 instantiate_decl (decl, /*defer_ok=*/1,
11159 /*expl_inst_class_mem_p=*/true);
11162 /* Perform an explicit instantiation of template class T. STORAGE, if
11163 non-null, is the RID for extern, inline or static. COMPLAIN is
11164 nonzero if this is called from the parser, zero if called recursively,
11165 since the standard is unclear (as detailed below). */
11168 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain)
11173 int previous_instantiation_extern_p = 0;
11175 if (TREE_CODE (t) == TYPE_DECL)
11178 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t))
11180 error ("explicit instantiation of non-template type %qT", t);
11186 if (!COMPLETE_TYPE_P (t))
11188 if (complain & tf_error)
11189 error ("explicit instantiation of %q#T before definition of template",
11194 if (storage != NULL_TREE)
11196 if (pedantic && !in_system_header)
11197 pedwarn("ISO C++ forbids the use of %qE on explicit instantiations",
11200 if (storage == ridpointers[(int) RID_INLINE])
11202 else if (storage == ridpointers[(int) RID_EXTERN])
11204 else if (storage == ridpointers[(int) RID_STATIC])
11208 error ("storage class %qD applied to template instantiation",
11214 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t))
11216 /* DR 259 [temp.spec].
11218 Both an explicit instantiation and a declaration of an explicit
11219 specialization shall not appear in a program unless the explicit
11220 instantiation follows a declaration of the explicit specialization.
11222 For a given set of template parameters, if an explicit
11223 instantiation of a template appears after a declaration of an
11224 explicit specialization for that template, the explicit
11225 instantiation has no effect. */
11228 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t))
11232 No program shall explicitly instantiate any template more
11235 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit
11236 instantiation was `extern'. If EXTERN_P then the second is.
11237 These cases are OK. */
11238 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t);
11240 if (!previous_instantiation_extern_p && !extern_p
11241 && (complain & tf_error))
11242 pedwarn ("duplicate explicit instantiation of %q#T", t);
11244 /* If we've already instantiated the template, just return now. */
11245 if (!CLASSTYPE_INTERFACE_ONLY (t))
11249 check_explicit_instantiation_namespace (TYPE_NAME (t));
11250 mark_class_instantiated (t, extern_p);
11258 /* In contrast to implicit instantiation, where only the
11259 declarations, and not the definitions, of members are
11260 instantiated, we have here:
11264 The explicit instantiation of a class template specialization
11265 implies the instantiation of all of its members not
11266 previously explicitly specialized in the translation unit
11267 containing the explicit instantiation.
11269 Of course, we can't instantiate member template classes, since
11270 we don't have any arguments for them. Note that the standard
11271 is unclear on whether the instantiation of the members are
11272 *explicit* instantiations or not. However, the most natural
11273 interpretation is that it should be an explicit instantiation. */
11276 for (tmp = TYPE_METHODS (t); tmp; tmp = TREE_CHAIN (tmp))
11277 if (TREE_CODE (tmp) == FUNCTION_DECL
11278 && DECL_TEMPLATE_INSTANTIATION (tmp))
11279 instantiate_class_member (tmp, extern_p);
11281 for (tmp = TYPE_FIELDS (t); tmp; tmp = TREE_CHAIN (tmp))
11282 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp))
11283 instantiate_class_member (tmp, extern_p);
11285 if (CLASSTYPE_NESTED_UTDS (t))
11286 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t),
11287 bt_instantiate_type_proc, &storage);
11291 /* Given a function DECL, which is a specialization of TMPL, modify
11292 DECL to be a re-instantiation of TMPL with the same template
11293 arguments. TMPL should be the template into which tsubst'ing
11294 should occur for DECL, not the most general template.
11296 One reason for doing this is a scenario like this:
11299 void f(const T&, int i);
11301 void g() { f(3, 7); }
11304 void f(const T& t, const int i) { }
11306 Note that when the template is first instantiated, with
11307 instantiate_template, the resulting DECL will have no name for the
11308 first parameter, and the wrong type for the second. So, when we go
11309 to instantiate the DECL, we regenerate it. */
11312 regenerate_decl_from_template (tree decl, tree tmpl)
11314 /* The arguments used to instantiate DECL, from the most general
11319 args = DECL_TI_ARGS (decl);
11320 code_pattern = DECL_TEMPLATE_RESULT (tmpl);
11322 /* Make sure that we can see identifiers, and compute access
11324 push_access_scope (decl);
11326 if (TREE_CODE (decl) == FUNCTION_DECL)
11334 args_depth = TMPL_ARGS_DEPTH (args);
11335 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl));
11336 if (args_depth > parms_depth)
11337 args = get_innermost_template_args (args, parms_depth);
11339 specs = tsubst_exception_specification (TREE_TYPE (code_pattern),
11340 args, tf_error, NULL_TREE);
11342 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl),
11345 /* Merge parameter declarations. */
11346 decl_parm = skip_artificial_parms_for (decl,
11347 DECL_ARGUMENTS (decl));
11349 = skip_artificial_parms_for (code_pattern,
11350 DECL_ARGUMENTS (code_pattern));
11356 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm))
11357 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm);
11358 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error,
11360 parm_type = type_decays_to (parm_type);
11361 if (!same_type_p (TREE_TYPE (decl_parm), parm_type))
11362 TREE_TYPE (decl_parm) = parm_type;
11363 attributes = DECL_ATTRIBUTES (pattern_parm);
11364 if (DECL_ATTRIBUTES (decl_parm) != attributes)
11366 DECL_ATTRIBUTES (decl_parm) = attributes;
11367 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0);
11369 decl_parm = TREE_CHAIN (decl_parm);
11370 pattern_parm = TREE_CHAIN (pattern_parm);
11373 /* Merge additional specifiers from the CODE_PATTERN. */
11374 if (DECL_DECLARED_INLINE_P (code_pattern)
11375 && !DECL_DECLARED_INLINE_P (decl))
11376 DECL_DECLARED_INLINE_P (decl) = 1;
11377 if (DECL_INLINE (code_pattern) && !DECL_INLINE (decl))
11378 DECL_INLINE (decl) = 1;
11380 else if (TREE_CODE (decl) == VAR_DECL)
11381 DECL_INITIAL (decl) =
11382 tsubst_expr (DECL_INITIAL (code_pattern), args,
11383 tf_error, DECL_TI_TEMPLATE (decl));
11385 gcc_unreachable ();
11387 pop_access_scope (decl);
11390 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be
11391 substituted to get DECL. */
11394 template_for_substitution (tree decl)
11396 tree tmpl = DECL_TI_TEMPLATE (decl);
11398 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern
11399 for the instantiation. This is not always the most general
11400 template. Consider, for example:
11403 struct S { template <class U> void f();
11404 template <> void f<int>(); };
11406 and an instantiation of S<double>::f<int>. We want TD to be the
11407 specialization S<T>::f<int>, not the more general S<T>::f<U>. */
11408 while (/* An instantiation cannot have a definition, so we need a
11409 more general template. */
11410 DECL_TEMPLATE_INSTANTIATION (tmpl)
11411 /* We must also deal with friend templates. Given:
11413 template <class T> struct S {
11414 template <class U> friend void f() {};
11417 S<int>::f<U> say, is not an instantiation of S<T>::f<U>,
11418 so far as the language is concerned, but that's still
11419 where we get the pattern for the instantiation from. On
11420 other hand, if the definition comes outside the class, say:
11422 template <class T> struct S {
11423 template <class U> friend void f();
11425 template <class U> friend void f() {}
11427 we don't need to look any further. That's what the check for
11428 DECL_INITIAL is for. */
11429 || (TREE_CODE (decl) == FUNCTION_DECL
11430 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl)
11431 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl))))
11433 /* The present template, TD, should not be a definition. If it
11434 were a definition, we should be using it! Note that we
11435 cannot restructure the loop to just keep going until we find
11436 a template with a definition, since that might go too far if
11437 a specialization was declared, but not defined. */
11438 gcc_assert (TREE_CODE (decl) != VAR_DECL
11439 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl)));
11441 /* Fetch the more general template. */
11442 tmpl = DECL_TI_TEMPLATE (tmpl);
11448 /* Produce the definition of D, a _DECL generated from a template. If
11449 DEFER_OK is nonzero, then we don't have to actually do the
11450 instantiation now; we just have to do it sometime. Normally it is
11451 an error if this is an explicit instantiation but D is undefined.
11452 EXPL_INST_CLASS_MEM_P is true iff D is a member of an
11453 explicitly instantiated class template. */
11456 instantiate_decl (tree d, int defer_ok,
11457 bool expl_inst_class_mem_p)
11459 tree tmpl = DECL_TI_TEMPLATE (d);
11466 bool pattern_defined;
11468 location_t saved_loc = input_location;
11471 /* This function should only be used to instantiate templates for
11472 functions and static member variables. */
11473 gcc_assert (TREE_CODE (d) == FUNCTION_DECL
11474 || TREE_CODE (d) == VAR_DECL);
11476 /* Variables are never deferred; if instantiation is required, they
11477 are instantiated right away. That allows for better code in the
11478 case that an expression refers to the value of the variable --
11479 if the variable has a constant value the referring expression can
11480 take advantage of that fact. */
11481 if (TREE_CODE (d) == VAR_DECL)
11484 /* Don't instantiate cloned functions. Instead, instantiate the
11485 functions they cloned. */
11486 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d))
11487 d = DECL_CLONED_FUNCTION (d);
11489 if (DECL_TEMPLATE_INSTANTIATED (d))
11490 /* D has already been instantiated. It might seem reasonable to
11491 check whether or not D is an explicit instantiation, and, if so,
11492 stop here. But when an explicit instantiation is deferred
11493 until the end of the compilation, DECL_EXPLICIT_INSTANTIATION
11494 is set, even though we still need to do the instantiation. */
11497 /* If we already have a specialization of this declaration, then
11498 there's no reason to instantiate it. Note that
11499 retrieve_specialization gives us both instantiations and
11500 specializations, so we must explicitly check
11501 DECL_TEMPLATE_SPECIALIZATION. */
11502 gen_tmpl = most_general_template (tmpl);
11503 gen_args = DECL_TI_ARGS (d);
11504 spec = retrieve_specialization (gen_tmpl, gen_args,
11505 /*class_specializations_p=*/false);
11506 if (spec != NULL_TREE && DECL_TEMPLATE_SPECIALIZATION (spec))
11509 /* This needs to happen before any tsubsting. */
11510 if (! push_tinst_level (d))
11513 timevar_push (TV_PARSE);
11515 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern
11516 for the instantiation. */
11517 td = template_for_substitution (d);
11518 code_pattern = DECL_TEMPLATE_RESULT (td);
11520 /* We should never be trying to instantiate a member of a class
11521 template or partial specialization. */
11522 gcc_assert (d != code_pattern);
11524 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d))
11525 || DECL_TEMPLATE_SPECIALIZATION (td))
11526 /* In the case of a friend template whose definition is provided
11527 outside the class, we may have too many arguments. Drop the
11528 ones we don't need. The same is true for specializations. */
11529 args = get_innermost_template_args
11530 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td)));
11534 if (TREE_CODE (d) == FUNCTION_DECL)
11535 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE);
11537 pattern_defined = ! DECL_IN_AGGR_P (code_pattern);
11539 /* We may be in the middle of deferred access check. Disable it now. */
11540 push_deferring_access_checks (dk_no_deferred);
11542 /* Unless an explicit instantiation directive has already determined
11543 the linkage of D, remember that a definition is available for
11545 if (pattern_defined
11546 && !DECL_INTERFACE_KNOWN (d)
11547 && !DECL_NOT_REALLY_EXTERN (d))
11548 mark_definable (d);
11550 input_location = DECL_SOURCE_LOCATION (d);
11552 /* If D is a member of an explicitly instantiated class template,
11553 and no definition is available, treat it like an implicit
11555 if (!pattern_defined && expl_inst_class_mem_p
11556 && DECL_EXPLICIT_INSTANTIATION (d))
11558 DECL_NOT_REALLY_EXTERN (d) = 0;
11559 DECL_INTERFACE_KNOWN (d) = 0;
11560 SET_DECL_IMPLICIT_INSTANTIATION (d);
11565 /* Recheck the substitutions to obtain any warning messages
11566 about ignoring cv qualifiers. */
11567 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl);
11568 tree type = TREE_TYPE (gen);
11570 /* Make sure that we can see identifiers, and compute access
11571 correctly. D is already the target FUNCTION_DECL with the
11573 push_access_scope (d);
11575 if (TREE_CODE (gen) == FUNCTION_DECL)
11577 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_error | tf_warning, d);
11578 tsubst (TYPE_RAISES_EXCEPTIONS (type), gen_args,
11579 tf_error | tf_warning, d);
11580 /* Don't simply tsubst the function type, as that will give
11581 duplicate warnings about poor parameter qualifications.
11582 The function arguments are the same as the decl_arguments
11583 without the top level cv qualifiers. */
11584 type = TREE_TYPE (type);
11586 tsubst (type, gen_args, tf_error | tf_warning, d);
11588 pop_access_scope (d);
11591 /* Check to see whether we know that this template will be
11592 instantiated in some other file, as with "extern template"
11594 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d));
11595 /* In general, we do not instantiate such templates... */
11597 /* ... but we instantiate inline functions so that we can inline
11599 && ! (TREE_CODE (d) == FUNCTION_DECL && DECL_INLINE (d))
11600 /* ... we instantiate static data members whose values are
11601 needed in integral constant expressions. */
11602 && ! (TREE_CODE (d) == VAR_DECL
11603 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (d)))
11605 /* Defer all other templates, unless we have been explicitly
11606 forbidden from doing so. */
11607 if (/* If there is no definition, we cannot instantiate the
11610 /* If it's OK to postpone instantiation, do so. */
11612 /* If this is a static data member that will be defined
11613 elsewhere, we don't want to instantiate the entire data
11614 member, but we do want to instantiate the initializer so that
11615 we can substitute that elsewhere. */
11616 || (external_p && TREE_CODE (d) == VAR_DECL))
11618 /* The definition of the static data member is now required so
11619 we must substitute the initializer. */
11620 if (TREE_CODE (d) == VAR_DECL
11621 && !DECL_INITIAL (d)
11622 && DECL_INITIAL (code_pattern))
11627 ns = decl_namespace_context (d);
11628 push_nested_namespace (ns);
11629 push_nested_class (DECL_CONTEXT (d));
11630 init = tsubst_expr (DECL_INITIAL (code_pattern),
11632 tf_error | tf_warning, NULL_TREE);
11633 DECL_INITIAL (d) = init;
11634 cp_finish_decl (d, init, /*asmspec_tree=*/NULL_TREE,
11635 LOOKUP_ONLYCONVERTING);
11636 pop_nested_class ();
11637 pop_nested_namespace (ns);
11640 /* We restore the source position here because it's used by
11641 add_pending_template. */
11642 input_location = saved_loc;
11644 if (at_eof && !pattern_defined
11645 && DECL_EXPLICIT_INSTANTIATION (d))
11648 The definition of a non-exported function template, a
11649 non-exported member function template, or a non-exported
11650 member function or static data member of a class template
11651 shall be present in every translation unit in which it is
11652 explicitly instantiated. */
11654 ("explicit instantiation of %qD but no definition available", d);
11656 /* ??? Historically, we have instantiated inline functions, even
11657 when marked as "extern template". */
11658 if (!(external_p && TREE_CODE (d) == VAR_DECL))
11659 add_pending_template (d);
11662 /* Tell the repository that D is available in this translation unit
11663 -- and see if it is supposed to be instantiated here. */
11664 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d))
11666 /* In a PCH file, despite the fact that the repository hasn't
11667 requested instantiation in the PCH it is still possible that
11668 an instantiation will be required in a file that includes the
11671 add_pending_template (d);
11672 /* Instantiate inline functions so that the inliner can do its
11673 job, even though we'll not be emitting a copy of this
11675 if (!(TREE_CODE (d) == FUNCTION_DECL
11676 && flag_inline_trees
11677 && DECL_DECLARED_INLINE_P (d)))
11681 need_push = !cfun || !global_bindings_p ();
11683 push_to_top_level ();
11685 /* Mark D as instantiated so that recursive calls to
11686 instantiate_decl do not try to instantiate it again. */
11687 DECL_TEMPLATE_INSTANTIATED (d) = 1;
11689 /* Regenerate the declaration in case the template has been modified
11690 by a subsequent redeclaration. */
11691 regenerate_decl_from_template (d, td);
11693 /* We already set the file and line above. Reset them now in case
11694 they changed as a result of calling regenerate_decl_from_template. */
11695 input_location = DECL_SOURCE_LOCATION (d);
11697 if (TREE_CODE (d) == VAR_DECL)
11699 /* Clear out DECL_RTL; whatever was there before may not be right
11700 since we've reset the type of the declaration. */
11701 SET_DECL_RTL (d, NULL_RTX);
11702 DECL_IN_AGGR_P (d) = 0;
11704 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the
11705 initializer. That function will defer actual emission until
11706 we have a chance to determine linkage. */
11707 DECL_EXTERNAL (d) = 0;
11709 /* Enter the scope of D so that access-checking works correctly. */
11710 push_nested_class (DECL_CONTEXT (d));
11711 cp_finish_decl (d, DECL_INITIAL (d), NULL_TREE, 0);
11712 pop_nested_class ();
11714 else if (TREE_CODE (d) == FUNCTION_DECL)
11716 htab_t saved_local_specializations;
11721 /* Save away the current list, in case we are instantiating one
11722 template from within the body of another. */
11723 saved_local_specializations = local_specializations;
11725 /* Set up the list of local specializations. */
11726 local_specializations = htab_create (37,
11727 hash_local_specialization,
11728 eq_local_specializations,
11731 /* Set up context. */
11732 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED);
11734 /* Create substitution entries for the parameters. */
11735 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d));
11736 tmpl_parm = DECL_ARGUMENTS (subst_decl);
11737 spec_parm = DECL_ARGUMENTS (d);
11738 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d))
11740 register_local_specialization (spec_parm, tmpl_parm);
11741 spec_parm = skip_artificial_parms_for (d, spec_parm);
11742 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm);
11746 register_local_specialization (spec_parm, tmpl_parm);
11747 tmpl_parm = TREE_CHAIN (tmpl_parm);
11748 spec_parm = TREE_CHAIN (spec_parm);
11750 gcc_assert (!spec_parm);
11752 /* Substitute into the body of the function. */
11753 tsubst_expr (DECL_SAVED_TREE (code_pattern), args,
11754 tf_error | tf_warning, tmpl);
11756 /* We don't need the local specializations any more. */
11757 htab_delete (local_specializations);
11758 local_specializations = saved_local_specializations;
11760 /* Finish the function. */
11761 d = finish_function (0);
11762 expand_or_defer_fn (d);
11765 /* We're not deferring instantiation any more. */
11766 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0;
11769 pop_from_top_level ();
11772 input_location = saved_loc;
11773 pop_deferring_access_checks ();
11774 pop_tinst_level ();
11776 timevar_pop (TV_PARSE);
11781 /* Run through the list of templates that we wish we could
11782 instantiate, and instantiate any we can. RETRIES is the
11783 number of times we retry pending template instantiation. */
11786 instantiate_pending_templates (int retries)
11789 tree last = NULL_TREE;
11791 location_t saved_loc = input_location;
11792 int saved_in_system_header = in_system_header;
11794 /* Instantiating templates may trigger vtable generation. This in turn
11795 may require further template instantiations. We place a limit here
11796 to avoid infinite loop. */
11797 if (pending_templates && retries >= max_tinst_depth)
11799 error ("template instantiation depth exceeds maximum of %d"
11800 " instantiating %q+D, possibly from virtual table generation"
11801 " (use -ftemplate-depth-NN to increase the maximum)",
11802 max_tinst_depth, TREE_VALUE (pending_templates));
11810 t = &pending_templates;
11813 tree instantiation = TREE_VALUE (*t);
11815 reopen_tinst_level (TREE_PURPOSE (*t));
11817 if (TYPE_P (instantiation))
11821 if (!COMPLETE_TYPE_P (instantiation))
11823 instantiate_class_template (instantiation);
11824 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation))
11825 for (fn = TYPE_METHODS (instantiation);
11827 fn = TREE_CHAIN (fn))
11828 if (! DECL_ARTIFICIAL (fn))
11829 instantiate_decl (fn,
11831 /*expl_inst_class_mem_p=*/false);
11832 if (COMPLETE_TYPE_P (instantiation))
11836 if (COMPLETE_TYPE_P (instantiation))
11837 /* If INSTANTIATION has been instantiated, then we don't
11838 need to consider it again in the future. */
11839 *t = TREE_CHAIN (*t);
11843 t = &TREE_CHAIN (*t);
11848 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation)
11849 && !DECL_TEMPLATE_INSTANTIATED (instantiation))
11852 = instantiate_decl (instantiation,
11854 /*expl_inst_class_mem_p=*/false);
11855 if (DECL_TEMPLATE_INSTANTIATED (instantiation))
11859 if (DECL_TEMPLATE_SPECIALIZATION (instantiation)
11860 || DECL_TEMPLATE_INSTANTIATED (instantiation))
11861 /* If INSTANTIATION has been instantiated, then we don't
11862 need to consider it again in the future. */
11863 *t = TREE_CHAIN (*t);
11867 t = &TREE_CHAIN (*t);
11871 current_tinst_level = NULL_TREE;
11873 last_pending_template = last;
11875 while (reconsider);
11877 input_location = saved_loc;
11878 in_system_header = saved_in_system_header;
11881 /* Substitute ARGVEC into T, which is a list of initializers for
11882 either base class or a non-static data member. The TREE_PURPOSEs
11883 are DECLs, and the TREE_VALUEs are the initializer values. Used by
11884 instantiate_decl. */
11887 tsubst_initializer_list (tree t, tree argvec)
11889 tree inits = NULL_TREE;
11891 for (; t; t = TREE_CHAIN (t))
11896 decl = tsubst_copy (TREE_PURPOSE (t), argvec, tf_error | tf_warning,
11898 decl = expand_member_init (decl);
11899 if (decl && !DECL_P (decl))
11900 in_base_initializer = 1;
11902 init = tsubst_expr (TREE_VALUE (t), argvec, tf_error | tf_warning,
11904 in_base_initializer = 0;
11908 init = build_tree_list (decl, init);
11909 TREE_CHAIN (init) = inits;
11916 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */
11919 set_current_access_from_decl (tree decl)
11921 if (TREE_PRIVATE (decl))
11922 current_access_specifier = access_private_node;
11923 else if (TREE_PROTECTED (decl))
11924 current_access_specifier = access_protected_node;
11926 current_access_specifier = access_public_node;
11929 /* Instantiate an enumerated type. TAG is the template type, NEWTAG
11930 is the instantiation (which should have been created with
11931 start_enum) and ARGS are the template arguments to use. */
11934 tsubst_enum (tree tag, tree newtag, tree args)
11938 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e))
11943 decl = TREE_VALUE (e);
11944 /* Note that in a template enum, the TREE_VALUE is the
11945 CONST_DECL, not the corresponding INTEGER_CST. */
11946 value = tsubst_expr (DECL_INITIAL (decl),
11947 args, tf_error | tf_warning,
11950 /* Give this enumeration constant the correct access. */
11951 set_current_access_from_decl (decl);
11953 /* Actually build the enumerator itself. */
11954 build_enumerator (DECL_NAME (decl), value, newtag);
11957 finish_enum (newtag);
11958 DECL_SOURCE_LOCATION (TYPE_NAME (newtag))
11959 = DECL_SOURCE_LOCATION (TYPE_NAME (tag));
11962 /* DECL is a FUNCTION_DECL that is a template specialization. Return
11963 its type -- but without substituting the innermost set of template
11964 arguments. So, innermost set of template parameters will appear in
11968 get_mostly_instantiated_function_type (tree decl)
11976 tmpl = most_general_template (DECL_TI_TEMPLATE (decl));
11977 targs = DECL_TI_ARGS (decl);
11978 tparms = DECL_TEMPLATE_PARMS (tmpl);
11979 parm_depth = TMPL_PARMS_DEPTH (tparms);
11981 /* There should be as many levels of arguments as there are levels
11983 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs));
11985 fn_type = TREE_TYPE (tmpl);
11987 if (parm_depth == 1)
11988 /* No substitution is necessary. */
11992 int i, save_access_control;
11995 /* Replace the innermost level of the TARGS with NULL_TREEs to
11996 let tsubst know not to substitute for those parameters. */
11997 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs));
11998 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i)
11999 SET_TMPL_ARGS_LEVEL (partial_args, i,
12000 TMPL_ARGS_LEVEL (targs, i));
12001 SET_TMPL_ARGS_LEVEL (partial_args,
12002 TMPL_ARGS_DEPTH (targs),
12003 make_tree_vec (DECL_NTPARMS (tmpl)));
12005 /* Disable access control as this function is used only during
12007 save_access_control = flag_access_control;
12008 flag_access_control = 0;
12010 ++processing_template_decl;
12011 /* Now, do the (partial) substitution to figure out the
12012 appropriate function type. */
12013 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE);
12014 --processing_template_decl;
12016 /* Substitute into the template parameters to obtain the real
12017 innermost set of parameters. This step is important if the
12018 innermost set of template parameters contains value
12019 parameters whose types depend on outer template parameters. */
12020 TREE_VEC_LENGTH (partial_args)--;
12021 tparms = tsubst_template_parms (tparms, partial_args, tf_error);
12023 flag_access_control = save_access_control;
12029 /* Return truthvalue if we're processing a template different from
12030 the last one involved in diagnostics. */
12032 problematic_instantiation_changed (void)
12034 return last_template_error_tick != tinst_level_tick;
12037 /* Remember current template involved in diagnostics. */
12039 record_last_problematic_instantiation (void)
12041 last_template_error_tick = tinst_level_tick;
12045 current_instantiation (void)
12047 return current_tinst_level;
12050 /* [temp.param] Check that template non-type parm TYPE is of an allowable
12051 type. Return zero for ok, nonzero for disallowed. Issue error and
12052 warning messages under control of COMPLAIN. */
12055 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain)
12057 if (INTEGRAL_TYPE_P (type))
12059 else if (POINTER_TYPE_P (type))
12061 else if (TYPE_PTR_TO_MEMBER_P (type))
12063 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
12065 else if (TREE_CODE (type) == TYPENAME_TYPE)
12068 if (complain & tf_error)
12069 error ("%q#T is not a valid type for a template constant parameter", type);
12073 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type].
12074 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/
12077 dependent_type_p_r (tree type)
12083 A type is dependent if it is:
12085 -- a template parameter. Template template parameters are types
12086 for us (since TYPE_P holds true for them) so we handle
12088 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
12089 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM)
12091 /* -- a qualified-id with a nested-name-specifier which contains a
12092 class-name that names a dependent type or whose unqualified-id
12093 names a dependent type. */
12094 if (TREE_CODE (type) == TYPENAME_TYPE)
12096 /* -- a cv-qualified type where the cv-unqualified type is
12098 type = TYPE_MAIN_VARIANT (type);
12099 /* -- a compound type constructed from any dependent type. */
12100 if (TYPE_PTR_TO_MEMBER_P (type))
12101 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type))
12102 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE
12104 else if (TREE_CODE (type) == POINTER_TYPE
12105 || TREE_CODE (type) == REFERENCE_TYPE)
12106 return dependent_type_p (TREE_TYPE (type));
12107 else if (TREE_CODE (type) == FUNCTION_TYPE
12108 || TREE_CODE (type) == METHOD_TYPE)
12112 if (dependent_type_p (TREE_TYPE (type)))
12114 for (arg_type = TYPE_ARG_TYPES (type);
12116 arg_type = TREE_CHAIN (arg_type))
12117 if (dependent_type_p (TREE_VALUE (arg_type)))
12121 /* -- an array type constructed from any dependent type or whose
12122 size is specified by a constant expression that is
12123 value-dependent. */
12124 if (TREE_CODE (type) == ARRAY_TYPE)
12126 if (TYPE_DOMAIN (type)
12127 && ((value_dependent_expression_p
12128 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
12129 || (type_dependent_expression_p
12130 (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))))
12132 return dependent_type_p (TREE_TYPE (type));
12135 /* -- a template-id in which either the template name is a template
12137 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM)
12139 /* ... or any of the template arguments is a dependent type or
12140 an expression that is type-dependent or value-dependent. */
12141 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type)
12142 && (any_dependent_template_arguments_p
12143 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)))))
12146 /* All TYPEOF_TYPEs are dependent; if the argument of the `typeof'
12147 expression is not type-dependent, then it should already been
12149 if (TREE_CODE (type) == TYPEOF_TYPE)
12152 /* The standard does not specifically mention types that are local
12153 to template functions or local classes, but they should be
12154 considered dependent too. For example:
12156 template <int I> void f() {
12161 The size of `E' cannot be known until the value of `I' has been
12162 determined. Therefore, `E' must be considered dependent. */
12163 scope = TYPE_CONTEXT (type);
12164 if (scope && TYPE_P (scope))
12165 return dependent_type_p (scope);
12166 else if (scope && TREE_CODE (scope) == FUNCTION_DECL)
12167 return type_dependent_expression_p (scope);
12169 /* Other types are non-dependent. */
12173 /* Returns TRUE if TYPE is dependent, in the sense of
12174 [temp.dep.type]. */
12177 dependent_type_p (tree type)
12179 /* If there are no template parameters in scope, then there can't be
12180 any dependent types. */
12181 if (!processing_template_decl)
12184 /* If the type is NULL, we have not computed a type for the entity
12185 in question; in that case, the type is dependent. */
12189 /* Erroneous types can be considered non-dependent. */
12190 if (type == error_mark_node)
12193 /* If we have not already computed the appropriate value for TYPE,
12195 if (!TYPE_DEPENDENT_P_VALID (type))
12197 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type);
12198 TYPE_DEPENDENT_P_VALID (type) = 1;
12201 return TYPE_DEPENDENT_P (type);
12204 /* Returns TRUE if EXPRESSION is dependent, according to CRITERION. */
12207 dependent_scope_ref_p (tree expression, bool criterion (tree))
12212 gcc_assert (TREE_CODE (expression) == SCOPE_REF);
12214 if (!TYPE_P (TREE_OPERAND (expression, 0)))
12217 scope = TREE_OPERAND (expression, 0);
12218 name = TREE_OPERAND (expression, 1);
12222 An id-expression is type-dependent if it contains a
12223 nested-name-specifier that contains a class-name that names a
12225 /* The suggested resolution to Core Issue 2 implies that if the
12226 qualifying type is the current class, then we must peek
12229 && currently_open_class (scope)
12230 && !criterion (name))
12232 if (dependent_type_p (scope))
12238 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of
12239 [temp.dep.constexpr] */
12242 value_dependent_expression_p (tree expression)
12244 if (!processing_template_decl)
12247 /* A name declared with a dependent type. */
12248 if (DECL_P (expression) && type_dependent_expression_p (expression))
12251 switch (TREE_CODE (expression))
12253 case IDENTIFIER_NODE:
12254 /* A name that has not been looked up -- must be dependent. */
12257 case TEMPLATE_PARM_INDEX:
12258 /* A non-type template parm. */
12262 /* A non-type template parm. */
12263 if (DECL_TEMPLATE_PARM_P (expression))
12268 /* A constant with integral or enumeration type and is initialized
12269 with an expression that is value-dependent. */
12270 if (DECL_INITIAL (expression)
12271 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (expression))
12272 && value_dependent_expression_p (DECL_INITIAL (expression)))
12276 case DYNAMIC_CAST_EXPR:
12277 case STATIC_CAST_EXPR:
12278 case CONST_CAST_EXPR:
12279 case REINTERPRET_CAST_EXPR:
12281 /* These expressions are value-dependent if the type to which
12282 the cast occurs is dependent or the expression being casted
12283 is value-dependent. */
12285 tree type = TREE_TYPE (expression);
12287 if (dependent_type_p (type))
12290 /* A functional cast has a list of operands. */
12291 expression = TREE_OPERAND (expression, 0);
12294 /* If there are no operands, it must be an expression such
12295 as "int()". This should not happen for aggregate types
12296 because it would form non-constant expressions. */
12297 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
12302 if (TREE_CODE (expression) == TREE_LIST)
12304 for (; expression; expression = TREE_CHAIN (expression))
12305 if (value_dependent_expression_p (TREE_VALUE (expression)))
12310 return value_dependent_expression_p (expression);
12315 /* A `sizeof' expression is value-dependent if the operand is
12317 expression = TREE_OPERAND (expression, 0);
12318 if (TYPE_P (expression))
12319 return dependent_type_p (expression);
12320 return type_dependent_expression_p (expression);
12323 return dependent_scope_ref_p (expression, value_dependent_expression_p);
12325 case COMPONENT_REF:
12326 return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
12327 || value_dependent_expression_p (TREE_OPERAND (expression, 1)));
12330 /* A CALL_EXPR is value-dependent if any argument is
12331 value-dependent. Why do we have to handle CALL_EXPRs in this
12332 function at all? First, some function calls, those for which
12333 value_dependent_expression_p is true, man appear in constant
12334 expressions. Second, there appear to be bugs which result in
12335 other CALL_EXPRs reaching this point. */
12337 tree function = TREE_OPERAND (expression, 0);
12338 tree args = TREE_OPERAND (expression, 1);
12340 if (value_dependent_expression_p (function))
12346 if (TREE_CODE (args) == TREE_LIST)
12348 for (; args; args = TREE_CHAIN (args))
12349 if (value_dependent_expression_p (TREE_VALUE (args)))
12354 return value_dependent_expression_p (args);
12358 /* A constant expression is value-dependent if any subexpression is
12359 value-dependent. */
12360 switch (TREE_CODE_CLASS (TREE_CODE (expression)))
12362 case tcc_reference:
12364 return (value_dependent_expression_p
12365 (TREE_OPERAND (expression, 0)));
12367 case tcc_comparison:
12369 return ((value_dependent_expression_p
12370 (TREE_OPERAND (expression, 0)))
12371 || (value_dependent_expression_p
12372 (TREE_OPERAND (expression, 1))));
12374 case tcc_expression:
12377 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (expression)); ++i)
12378 /* In some cases, some of the operands may be missing.
12379 (For example, in the case of PREDECREMENT_EXPR, the
12380 amount to increment by may be missing.) That doesn't
12381 make the expression dependent. */
12382 if (TREE_OPERAND (expression, i)
12383 && (value_dependent_expression_p
12384 (TREE_OPERAND (expression, i))))
12394 /* The expression is not value-dependent. */
12398 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of
12399 [temp.dep.expr]. */
12402 type_dependent_expression_p (tree expression)
12404 if (!processing_template_decl)
12407 if (expression == error_mark_node)
12410 /* An unresolved name is always dependent. */
12411 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12414 /* Some expression forms are never type-dependent. */
12415 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR
12416 || TREE_CODE (expression) == SIZEOF_EXPR
12417 || TREE_CODE (expression) == ALIGNOF_EXPR
12418 || TREE_CODE (expression) == TYPEID_EXPR
12419 || TREE_CODE (expression) == DELETE_EXPR
12420 || TREE_CODE (expression) == VEC_DELETE_EXPR
12421 || TREE_CODE (expression) == THROW_EXPR)
12424 /* The types of these expressions depends only on the type to which
12425 the cast occurs. */
12426 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR
12427 || TREE_CODE (expression) == STATIC_CAST_EXPR
12428 || TREE_CODE (expression) == CONST_CAST_EXPR
12429 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR
12430 || TREE_CODE (expression) == CAST_EXPR)
12431 return dependent_type_p (TREE_TYPE (expression));
12433 /* The types of these expressions depends only on the type created
12434 by the expression. */
12435 if (TREE_CODE (expression) == NEW_EXPR
12436 || TREE_CODE (expression) == VEC_NEW_EXPR)
12438 /* For NEW_EXPR tree nodes created inside a template, either
12439 the object type itself or a TREE_LIST may appear as the
12441 tree type = TREE_OPERAND (expression, 1);
12442 if (TREE_CODE (type) == TREE_LIST)
12443 /* This is an array type. We need to check array dimensions
12445 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type)))
12446 || value_dependent_expression_p
12447 (TREE_OPERAND (TREE_VALUE (type), 1));
12449 return dependent_type_p (type);
12452 if (TREE_CODE (expression) == SCOPE_REF
12453 && dependent_scope_ref_p (expression,
12454 type_dependent_expression_p))
12457 if (TREE_CODE (expression) == FUNCTION_DECL
12458 && DECL_LANG_SPECIFIC (expression)
12459 && DECL_TEMPLATE_INFO (expression)
12460 && (any_dependent_template_arguments_p
12461 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression)))))
12464 if (TREE_CODE (expression) == TEMPLATE_DECL
12465 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression))
12468 if (TREE_TYPE (expression) == unknown_type_node)
12470 if (TREE_CODE (expression) == ADDR_EXPR)
12471 return type_dependent_expression_p (TREE_OPERAND (expression, 0));
12472 if (TREE_CODE (expression) == COMPONENT_REF
12473 || TREE_CODE (expression) == OFFSET_REF)
12475 if (type_dependent_expression_p (TREE_OPERAND (expression, 0)))
12477 expression = TREE_OPERAND (expression, 1);
12478 if (TREE_CODE (expression) == IDENTIFIER_NODE)
12481 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */
12482 if (TREE_CODE (expression) == SCOPE_REF)
12485 if (TREE_CODE (expression) == BASELINK)
12486 expression = BASELINK_FUNCTIONS (expression);
12488 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR)
12490 if (any_dependent_template_arguments_p
12491 (TREE_OPERAND (expression, 1)))
12493 expression = TREE_OPERAND (expression, 0);
12495 gcc_assert (TREE_CODE (expression) == OVERLOAD
12496 || TREE_CODE (expression) == FUNCTION_DECL);
12500 if (type_dependent_expression_p (OVL_CURRENT (expression)))
12502 expression = OVL_NEXT (expression);
12507 gcc_assert (TREE_CODE (expression) != TYPE_DECL);
12509 return (dependent_type_p (TREE_TYPE (expression)));
12512 /* Returns TRUE if ARGS (a TREE_LIST of arguments to a function call)
12513 contains a type-dependent expression. */
12516 any_type_dependent_arguments_p (tree args)
12520 tree arg = TREE_VALUE (args);
12522 if (type_dependent_expression_p (arg))
12524 args = TREE_CHAIN (args);
12529 /* Returns TRUE if the ARG (a template argument) is dependent. */
12532 dependent_template_arg_p (tree arg)
12534 if (!processing_template_decl)
12537 if (TREE_CODE (arg) == TEMPLATE_DECL
12538 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM)
12539 return dependent_template_p (arg);
12540 else if (TYPE_P (arg))
12541 return dependent_type_p (arg);
12543 return (type_dependent_expression_p (arg)
12544 || value_dependent_expression_p (arg));
12547 /* Returns true if ARGS (a collection of template arguments) contains
12548 any dependent arguments. */
12551 any_dependent_template_arguments_p (tree args)
12559 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i)
12561 tree level = TMPL_ARGS_LEVEL (args, i + 1);
12562 for (j = 0; j < TREE_VEC_LENGTH (level); ++j)
12563 if (dependent_template_arg_p (TREE_VEC_ELT (level, j)))
12570 /* Returns TRUE if the template TMPL is dependent. */
12573 dependent_template_p (tree tmpl)
12575 if (TREE_CODE (tmpl) == OVERLOAD)
12579 if (dependent_template_p (OVL_FUNCTION (tmpl)))
12581 tmpl = OVL_CHAIN (tmpl);
12586 /* Template template parameters are dependent. */
12587 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl)
12588 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM)
12590 /* So are names that have not been looked up. */
12591 if (TREE_CODE (tmpl) == SCOPE_REF
12592 || TREE_CODE (tmpl) == IDENTIFIER_NODE)
12594 /* So are member templates of dependent classes. */
12595 if (TYPE_P (CP_DECL_CONTEXT (tmpl)))
12596 return dependent_type_p (DECL_CONTEXT (tmpl));
12600 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */
12603 dependent_template_id_p (tree tmpl, tree args)
12605 return (dependent_template_p (tmpl)
12606 || any_dependent_template_arguments_p (args));
12609 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the
12610 TYPENAME_TYPE corresponds. Returns ERROR_MARK_NODE if no such TYPE
12611 can be found. Note that this function peers inside uninstantiated
12612 templates and therefore should be used only in extremely limited
12613 situations. ONLY_CURRENT_P restricts this peering to the currently
12614 open classes hierarchy (which is required when comparing types). */
12617 resolve_typename_type (tree type, bool only_current_p)
12625 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE);
12627 scope = TYPE_CONTEXT (type);
12628 name = TYPE_IDENTIFIER (type);
12630 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve
12631 it first before we can figure out what NAME refers to. */
12632 if (TREE_CODE (scope) == TYPENAME_TYPE)
12633 scope = resolve_typename_type (scope, only_current_p);
12634 /* If we don't know what SCOPE refers to, then we cannot resolve the
12636 if (scope == error_mark_node || TREE_CODE (scope) == TYPENAME_TYPE)
12637 return error_mark_node;
12638 /* If the SCOPE is a template type parameter, we have no way of
12639 resolving the name. */
12640 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM)
12642 /* If the SCOPE is not the current instantiation, there's no reason
12643 to look inside it. */
12644 if (only_current_p && !currently_open_class (scope))
12645 return error_mark_node;
12646 /* If SCOPE is a partial instantiation, it will not have a valid
12647 TYPE_FIELDS list, so use the original template. */
12648 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope);
12649 /* Enter the SCOPE so that name lookup will be resolved as if we
12650 were in the class definition. In particular, SCOPE will no
12651 longer be considered a dependent type. */
12652 pushed_scope = push_scope (scope);
12653 /* Look up the declaration. */
12654 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true);
12655 /* Obtain the set of qualifiers applied to the TYPE. */
12656 quals = cp_type_quals (type);
12657 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to
12658 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */
12660 type = error_mark_node;
12661 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE
12662 && TREE_CODE (decl) == TYPE_DECL)
12663 type = TREE_TYPE (decl);
12664 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR
12665 && DECL_CLASS_TEMPLATE_P (decl))
12669 /* Obtain the template and the arguments. */
12670 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0);
12671 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1);
12672 /* Instantiate the template. */
12673 type = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE,
12674 /*entering_scope=*/0, tf_error | tf_user);
12677 type = error_mark_node;
12678 /* Qualify the resulting type. */
12679 if (type != error_mark_node && quals)
12680 type = cp_build_qualified_type (type, quals);
12681 /* Leave the SCOPE. */
12683 pop_scope (pushed_scope);
12688 /* EXPR is an expression which is not type-dependent. Return a proxy
12689 for EXPR that can be used to compute the types of larger
12690 expressions containing EXPR. */
12693 build_non_dependent_expr (tree expr)
12697 /* Preserve null pointer constants so that the type of things like
12698 "p == 0" where "p" is a pointer can be determined. */
12699 if (null_ptr_cst_p (expr))
12701 /* Preserve OVERLOADs; the functions must be available to resolve
12703 inner_expr = (TREE_CODE (expr) == ADDR_EXPR ?
12704 TREE_OPERAND (expr, 0) :
12705 TREE_CODE (expr) == COMPONENT_REF ?
12706 TREE_OPERAND (expr, 1) : expr);
12707 if (is_overloaded_fn (inner_expr)
12708 || TREE_CODE (inner_expr) == OFFSET_REF)
12710 /* There is no need to return a proxy for a variable. */
12711 if (TREE_CODE (expr) == VAR_DECL)
12713 /* Preserve string constants; conversions from string constants to
12714 "char *" are allowed, even though normally a "const char *"
12715 cannot be used to initialize a "char *". */
12716 if (TREE_CODE (expr) == STRING_CST)
12718 /* Preserve arithmetic constants, as an optimization -- there is no
12719 reason to create a new node. */
12720 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST)
12722 /* Preserve THROW_EXPRs -- all throw-expressions have type "void".
12723 There is at least one place where we want to know that a
12724 particular expression is a throw-expression: when checking a ?:
12725 expression, there are special rules if the second or third
12726 argument is a throw-expression. */
12727 if (TREE_CODE (expr) == THROW_EXPR)
12730 if (TREE_CODE (expr) == COND_EXPR)
12731 return build3 (COND_EXPR,
12733 TREE_OPERAND (expr, 0),
12734 (TREE_OPERAND (expr, 1)
12735 ? build_non_dependent_expr (TREE_OPERAND (expr, 1))
12736 : build_non_dependent_expr (TREE_OPERAND (expr, 0))),
12737 build_non_dependent_expr (TREE_OPERAND (expr, 2)));
12738 if (TREE_CODE (expr) == COMPOUND_EXPR
12739 && !COMPOUND_EXPR_OVERLOADED (expr))
12740 return build2 (COMPOUND_EXPR,
12742 TREE_OPERAND (expr, 0),
12743 build_non_dependent_expr (TREE_OPERAND (expr, 1)));
12745 /* If the type is unknown, it can't really be non-dependent */
12746 gcc_assert (TREE_TYPE (expr) != unknown_type_node);
12748 /* Otherwise, build a NON_DEPENDENT_EXPR.
12750 REFERENCE_TYPEs are not stripped for expressions in templates
12751 because doing so would play havoc with mangling. Consider, for
12754 template <typename T> void f<T& g>() { g(); }
12756 In the body of "f", the expression for "g" will have
12757 REFERENCE_TYPE, even though the standard says that it should
12758 not. The reason is that we must preserve the syntactic form of
12759 the expression so that mangling (say) "f<g>" inside the body of
12760 "f" works out correctly. Therefore, the REFERENCE_TYPE is
12762 return build1 (NON_DEPENDENT_EXPR, non_reference (TREE_TYPE (expr)), expr);
12765 /* ARGS is a TREE_LIST of expressions as arguments to a function call.
12766 Return a new TREE_LIST with the various arguments replaced with
12767 equivalent non-dependent expressions. */
12770 build_non_dependent_args (tree args)
12775 new_args = NULL_TREE;
12776 for (a = args; a; a = TREE_CHAIN (a))
12777 new_args = tree_cons (NULL_TREE,
12778 build_non_dependent_expr (TREE_VALUE (a)),
12780 return nreverse (new_args);
12783 #include "gt-cp-pt.h"