[libcxx] r255518 - Missed this on the previous (255517) commit

[Marshall Clow via cfe-commits]

Author: marshall
Date: Mon Dec 14 12:02:23 2015
New Revision: 255518

URL: http://llvm.org/viewvc/llvm-project?rev=255518&view=rev
Log:
Missed this on the previous (255517) commit

Modified:
    libcxx/trunk/include/type_traits

Modified: libcxx/trunk/include/type_traits
URL: http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/type_traits?rev=255518&r1=255517&r2=255518&view=diff
==============================================================================
--- libcxx/trunk/include/type_traits (original)
+++ libcxx/trunk/include/type_traits Mon Dec 14 12:02:23 2015
@@ -396,6 +396,55 @@ template <class _Tp> struct _LIBCPP_TYPE
 template <bool _Bp, class _Tp = void> using enable_if_t = typename enable_if<_Bp, _Tp>::type;
 #endif
 
+// addressof
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+_Tp*
+addressof(_Tp& __x) _NOEXCEPT
+{
+    return (_Tp*)&reinterpret_cast<const volatile char&>(__x);
+}
+
+#if defined(_LIBCPP_HAS_OBJC_ARC) && !defined(_LIBCPP_PREDEFINED_OBJC_ARC_ADDRESSOF)
+// Objective-C++ Automatic Reference Counting uses qualified pointers
+// that require special addressof() signatures. When
+// _LIBCPP_PREDEFINED_OBJC_ARC_ADDRESSOF is defined, the compiler
+// itself is providing these definitions. Otherwise, we provide them.
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+__strong _Tp*
+addressof(__strong _Tp& __x) _NOEXCEPT
+{
+  return &__x;
+}
+
+#ifdef _LIBCPP_HAS_OBJC_ARC_WEAK
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+__weak _Tp*
+addressof(__weak _Tp& __x) _NOEXCEPT
+{
+  return &__x;
+}
+#endif
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+__autoreleasing _Tp*
+addressof(__autoreleasing _Tp& __x) _NOEXCEPT
+{
+  return &__x;
+}
+
+template <class _Tp>
+inline _LIBCPP_INLINE_VISIBILITY
+__unsafe_unretained _Tp*
+addressof(__unsafe_unretained _Tp& __x) _NOEXCEPT
+{
+  return &__x;
+}
+#endif
 
 struct __two {char __lx[2];};