From a3dc8f3b8bf0a6f1220f673f9f162bf09a743cbc Mon Sep 17 00:00:00 2001
From: Peter Collingbourne <peter@pcc.me.uk>
Date: Wed, 5 Feb 2014 01:44:17 +0000
Subject: [PATCH] Support forward_list<Incomplete Type>. Patch by Zhihao Yuan!

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@200814 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/forward_list                          | 27 +++++++++++--------
 .../default_recursive.pass.cpp                | 25 +++++++++++++++++
 2 files changed, 41 insertions(+), 11 deletions(-)
 create mode 100644 test/containers/sequences/forwardlist/forwardlist.cons/default_recursive.pass.cpp

diff --git a/include/forward_list b/include/forward_list
index 398226b8..72d31dc7 100644
--- a/include/forward_list
+++ b/include/forward_list
@@ -188,7 +188,6 @@ template <class _Tp, class _VoidPtr> struct __forward_list_node;
 template <class _NodePtr>
 struct __forward_begin_node
 {
-    typedef __forward_begin_node __self;
     typedef _NodePtr pointer;
 
     pointer __next_;
@@ -197,16 +196,22 @@ struct __forward_begin_node
 };
 
 template <class _Tp, class _VoidPtr>
-struct __forward_list_node
-    : public __forward_begin_node
-             <
-                 typename pointer_traits<_VoidPtr>::template
+struct _LIBCPP_HIDDEN __begin_node_of
+{
+    typedef __forward_begin_node
+        <
+             typename pointer_traits<_VoidPtr>::template
 #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
-                     rebind<__forward_list_node<_Tp, _VoidPtr> >
+                 rebind<__forward_list_node<_Tp, _VoidPtr> >
 #else
-                     rebind<__forward_list_node<_Tp, _VoidPtr> >::other
+                 rebind<__forward_list_node<_Tp, _VoidPtr> >::other
 #endif
-             >
+         > type;
+};
+
+template <class _Tp, class _VoidPtr>
+struct __forward_list_node
+    : public __begin_node_of<_Tp, _VoidPtr>::type
 {
     typedef _Tp value_type;
 
@@ -357,9 +362,9 @@ protected:
     typedef _Tp    value_type;
     typedef _Alloc allocator_type;
 
-    typedef typename allocator_traits<allocator_type>::void_pointer void_pointer;
-    typedef __forward_list_node<value_type, void_pointer>           __node;
-    typedef typename __node::__self                                 __begin_node;
+    typedef typename allocator_traits<allocator_type>::void_pointer  void_pointer;
+    typedef __forward_list_node<value_type, void_pointer>            __node;
+    typedef typename __begin_node_of<value_type, void_pointer>::type __begin_node;
     typedef typename allocator_traits<allocator_type>::template
 #ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
                 rebind_alloc<__node>
diff --git a/test/containers/sequences/forwardlist/forwardlist.cons/default_recursive.pass.cpp b/test/containers/sequences/forwardlist/forwardlist.cons/default_recursive.pass.cpp
new file mode 100644
index 00000000..5ff00e6f
--- /dev/null
+++ b/test/containers/sequences/forwardlist/forwardlist.cons/default_recursive.pass.cpp
@@ -0,0 +1,25 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <forward_list>
+
+// class forward_list
+
+// forward_list();
+
+#include <forward_list>
+
+struct X
+{
+    std::forward_list<X> q;
+};
+
+int main()
+{
+}