From 24e817d22383879994baa0a8ac61624f282f8f75 Mon Sep 17 00:00:00 2001
From: Eric Fiselier <eric@efcs.ca>
Date: Sun, 23 Aug 2015 02:34:18 +0000
Subject: [PATCH] Cleanup fancy pointer rebinding in list using
 __rebind_pointer.

Currently we need an #ifdef branch every time we use pointer traits to rebind a pointer because
it is done differently in C++11 and C++03. This patch introduces the __rebind_pointer utility to
clean this up.

llvm-svn: 245802
---
 libcxx/include/list   | 47 ++++++++-----------------------------------
 libcxx/include/memory |  9 +++++++++
 2 files changed, 17 insertions(+), 39 deletions(-)

diff --git a/libcxx/include/list b/libcxx/include/list
index 14201a80e348..0af65ab343c8 100644
--- a/libcxx/include/list
+++ b/libcxx/include/list
@@ -191,19 +191,10 @@ template <class _Tp, class _VoidPtr> struct __list_node;
 template <class _Tp, class _VoidPtr>
 struct __list_node_base
 {
-    typedef typename pointer_traits<_VoidPtr>::template
-#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
-        rebind<__list_node<_Tp, _VoidPtr> > pointer;
-#else
-        rebind<__list_node<_Tp, _VoidPtr> >::other pointer;
-#endif
-
-    typedef typename pointer_traits<_VoidPtr>::template
-#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
-        rebind<__list_node_base> __base_pointer;
-#else
-        rebind<__list_node_base>::other __base_pointer;
-#endif
+    typedef typename __rebind_pointer<_VoidPtr, __list_node<_Tp, _VoidPtr> >::type
+        pointer;
+    typedef typename __rebind_pointer<_VoidPtr, __list_node_base>::type
+        __base_pointer;
 
     pointer __prev_;
     pointer __next_;
@@ -232,12 +223,7 @@ template <class _Tp, class _VoidPtr> class _LIBCPP_TYPE_VIS_ONLY __list_const_it
 template <class _Tp, class _VoidPtr>
 class _LIBCPP_TYPE_VIS_ONLY __list_iterator
 {
-    typedef typename pointer_traits<_VoidPtr>::template
-#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
-        rebind<__list_node<_Tp, _VoidPtr> > __node_pointer;
-#else
-        rebind<__list_node<_Tp, _VoidPtr> >::other __node_pointer;
-#endif
+    typedef typename __list_node<_Tp, _VoidPtr>::pointer __node_pointer;
 
     __node_pointer __ptr_;
 
@@ -262,13 +248,7 @@ public:
     typedef bidirectional_iterator_tag       iterator_category;
     typedef _Tp                              value_type;
     typedef value_type&                      reference;
-    typedef typename pointer_traits<_VoidPtr>::template
-#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
-            rebind<value_type>
-#else
-            rebind<value_type>::other
-#endif
-                                             pointer;
+    typedef typename __rebind_pointer<_VoidPtr, value_type>::type pointer;
     typedef typename pointer_traits<pointer>::difference_type difference_type;
 
     _LIBCPP_INLINE_VISIBILITY
@@ -365,12 +345,7 @@ public:
 template <class _Tp, class _VoidPtr>
 class _LIBCPP_TYPE_VIS_ONLY __list_const_iterator
 {
-    typedef typename pointer_traits<_VoidPtr>::template
-#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
-        rebind<__list_node<_Tp, _VoidPtr> > __node_pointer;
-#else
-        rebind<__list_node<_Tp, _VoidPtr> >::other __node_pointer;
-#endif
+    typedef typename __list_node<_Tp, _VoidPtr>::pointer __node_pointer;
 
     __node_pointer __ptr_;
 
@@ -392,13 +367,7 @@ public:
     typedef bidirectional_iterator_tag       iterator_category;
     typedef _Tp                              value_type;
     typedef const value_type&                reference;
-    typedef typename pointer_traits<_VoidPtr>::template
-#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
-            rebind<const value_type>
-#else
-            rebind<const value_type>::other
-#endif
-                                             pointer;
+    typedef typename __rebind_pointer<_VoidPtr, const value_type>::type pointer;
     typedef typename pointer_traits<pointer>::difference_type difference_type;
 
     _LIBCPP_INLINE_VISIBILITY
diff --git a/libcxx/include/memory b/libcxx/include/memory
index 38ce433b2f2a..9d214beb68f6 100644
--- a/libcxx/include/memory
+++ b/libcxx/include/memory
@@ -932,6 +932,15 @@ public:
         {return _VSTD::addressof(__r);}
 };
 
+template <class _From, class _To>
+struct __rebind_pointer {
+#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
+    typedef typename pointer_traits<_From>::template rebind<_To>        type;
+#else
+    typedef typename pointer_traits<_From>::template rebind<_To>::other type;
+#endif
+};
+
 // allocator_traits
 
 namespace __has_pointer_type_imp