From bff1bfc6be0615ba3036a861fd27b75c96e3297c Mon Sep 17 00:00:00 2001
From: Howard Hinnant <hhinnant@apple.com>
Date: Tue, 1 May 2012 15:37:54 +0000
Subject: [PATCH] Greatly scale back ambitions of emulating move semantics in
 C++03 mode.  It was causing more problems than it solved.  This fixes
 http://llvm.org/bugs/show_bug.cgi?id=12704.

llvm-svn: 155918
---
 libcxx/include/memory      |  60 ++++++--------------
 libcxx/include/type_traits | 109 +++++++++----------------------------
 2 files changed, 43 insertions(+), 126 deletions(-)

diff --git a/libcxx/include/memory b/libcxx/include/memory
index aa24f960aecf..e30a6fd7c5b4 100644
--- a/libcxx/include/memory
+++ b/libcxx/include/memory
@@ -1685,39 +1685,21 @@ public:
             ::new((void*)__p) _Tp();
         }
 # if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
+
     template <class _A0>
         _LIBCPP_INLINE_VISIBILITY
-        typename enable_if
-        <
-            !is_convertible<_A0, __rv<_A0> >::value,
-            void
-        >::type
+        void
         construct(pointer __p, _A0& __a0)
         {
             ::new((void*)__p) _Tp(__a0);
         }
     template <class _A0>
         _LIBCPP_INLINE_VISIBILITY
-        typename enable_if
-        <
-            !is_convertible<_A0, __rv<_A0> >::value,
-            void
-        >::type
+        void
         construct(pointer __p, const _A0& __a0)
         {
             ::new((void*)__p) _Tp(__a0);
         }
-    template <class _A0>
-        _LIBCPP_INLINE_VISIBILITY
-        typename enable_if
-        <
-            is_convertible<_A0, __rv<_A0> >::value,
-            void
-        >::type
-        construct(pointer __p, _A0 __a0)
-        {
-            ::new((void*)__p) _Tp(_VSTD::move(__a0));
-        }
 # endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
     template <class _A0, class _A1>
         _LIBCPP_INLINE_VISIBILITY
@@ -1793,39 +1775,21 @@ public:
             ::new((void*)__p) _Tp();
         }
 # if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
+
     template <class _A0>
         _LIBCPP_INLINE_VISIBILITY
-        typename enable_if
-        <
-            !is_convertible<_A0, __rv<_A0> >::value,
-            void
-        >::type
+        void
         construct(pointer __p, _A0& __a0)
         {
             ::new((void*)__p) _Tp(__a0);
         }
     template <class _A0>
         _LIBCPP_INLINE_VISIBILITY
-        typename enable_if
-        <
-            !is_convertible<_A0, __rv<_A0> >::value,
-            void
-        >::type
+        void
         construct(pointer __p, const _A0& __a0)
         {
             ::new((void*)__p) _Tp(__a0);
         }
-    template <class _A0>
-        _LIBCPP_INLINE_VISIBILITY
-        typename enable_if
-        <
-            is_convertible<_A0, __rv<_A0> >::value,
-            void
-        >::type
-        construct(pointer __p, _A0 __a0)
-        {
-            ::new((void*)__p) _Tp(_VSTD::move(__a0));
-        }
 # endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
     template <class _A0, class _A1>
         _LIBCPP_INLINE_VISIBILITY
@@ -3086,6 +3050,18 @@ operator>=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
     return !(nullptr < __x);
 }
 
+#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
+
+template <class _Tp, class _Dp>
+inline _LIBCPP_INLINE_VISIBILITY
+unique_ptr<_Tp, _Dp>
+move(unique_ptr<_Tp, _Dp>& __t)
+{
+    return unique_ptr<_Tp, _Dp>(__rv<unique_ptr<_Tp, _Dp> >(__t));
+}
+
+#endif
+
 template <class _Tp> struct hash;
 
 // We use murmur2 when size_t is 32 bits, and cityhash64 when size_t
diff --git a/libcxx/include/type_traits b/libcxx/include/type_traits
index f68ed6dd29a1..a54e25204eeb 100644
--- a/libcxx/include/type_traits
+++ b/libcxx/include/type_traits
@@ -1297,6 +1297,31 @@ forward(typename std::remove_reference<_Tp>::type&& __t) _NOEXCEPT
 
 #else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+_Tp&
+move(_Tp& __t)
+{
+    return __t;
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+const _Tp&
+move(const _Tp& __t)
+{
+    return __t;
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+_Tp&
+forward(typename std::remove_reference<_Tp>::type& __t) _NOEXCEPT
+{
+    return __t;
+}
+
+
 template <class _Tp>
 class __rv
 {
@@ -1309,90 +1334,6 @@ public:
     explicit __rv(_Trr& __t) : t_(__t) {}
 };
 
-template <class _Tp>
-inline _LIBCPP_INLINE_VISIBILITY
-typename enable_if
-<
-    !is_convertible<_Tp, __rv<_Tp> >::value,
-    _Tp&
->::type
-move(_Tp& __t)
-{
-    return __t;
-}
-
-template <class _Tp>
-inline _LIBCPP_INLINE_VISIBILITY
-typename enable_if
-<
-    !is_convertible<_Tp, __rv<_Tp> >::value,
-    const _Tp&
->::type
-move(const _Tp& __t)
-{
-    return __t;
-}
-
-template <class _Tp>
-inline _LIBCPP_INLINE_VISIBILITY
-typename enable_if
-<
-    is_convertible<_Tp, __rv<_Tp> >::value,
-    _Tp
->::type
-move(_Tp& __t)
-{
-    return _Tp(__rv<_Tp>(__t));
-}
-
-template <class _Tp, class _Up>
-inline _LIBCPP_INLINE_VISIBILITY
-typename enable_if
-<
-    !is_convertible<_Tp, __rv<_Tp> >::value,
-    typename add_lvalue_reference<_Tp>::type
->::type
-forward(_Up& __t)
-{
-    return __t;
-}
-
-template <class _Tp, class _Up>
-inline _LIBCPP_INLINE_VISIBILITY
-typename enable_if
-<
-    !is_convertible<_Tp, __rv<_Tp> >::value,
-    typename add_lvalue_reference<_Tp>::type
->::type
-forward(const _Up& __t)
-{
-    return __t;
-}
-
-template <class _Tp, class _Up>
-inline _LIBCPP_INLINE_VISIBILITY
-typename enable_if
-<
-    is_convertible<_Tp, __rv<_Tp> >::value,
-    _Tp
->::type
-forward(_Up& __t)
-{
-    return _Tp(__rv<_Tp>(__t));
-}
-
-template <class _Tp, class _Up>
-inline _LIBCPP_INLINE_VISIBILITY
-typename enable_if
-<
-    is_convertible<_Tp, __rv<_Tp> >::value,
-    _Tp
->::type
-forward(const _Up& __t)
-{
-    return _Tp(__rv<_Tp>(__t));
-}
-
 #endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
 
 template <class _Tp>