Index: docs/DesignDocs/VisibilityMacros.rst
===================================================================
--- docs/DesignDocs/VisibilityMacros.rst
+++ docs/DesignDocs/VisibilityMacros.rst
@@ -22,6 +22,18 @@
   Mark a symbol as being exported by the libc++ library. This attribute must
   be applied to the declaration of all functions exported by the libc++ dylib.
 
+**_LIBCPP_OVERRIDABLE_FUNC_VIS**
+  Mark a symbol as being exported by the libc++ library, but allow it to be
+  overridden locally. On non-Windows, this is equivalent to `_LIBCPP_FUNC_VIS`.
+  This macro is applied to all `operator new` and `operator delete` overloads.
+
+  **Windows Behavior**: Any symbol marked `dllimport` cannot be overridden
+  locally, since `dllimport` indicates the symbol should be bound to a separate
+  DLL. All `operator new` and `operator delete` overloads are required to be
+  locally overridable, and therefore must not be marked `dllimport`. On Windows,
+  this macro therefore expands to `__declspec(dllexport)` when building the
+  library and has an empty definition otherwise.
+
 **_LIBCPP_INLINE_VISIBILITY**
   Mark a function as hidden and force inlining whenever possible.
 
@@ -107,20 +119,6 @@
   versioning namespace. This allows throwing and catching some exception types
   between libc++ and libstdc++.
 
-**_LIBCPP_NEW_DELETE_VIS**
-  Mark a symbol as being exported by the libc++ library. This macro must be
-  applied to all `operator new` and `operator delete` overloads.
-
-  **Windows Behavior**: The `operator new` and `operator delete` overloads
-  should not be marked as `dllimport`; if they were, source files including the
-  `<new>` header (either directly or transitively) would lose the ability to use
-  local overloads of `operator new` and `operator delete`. On Windows, this
-  macro therefore expands to `__declspec(dllexport)` when building the library
-  and has an empty definition otherwise. A related caveat is that libc++ must be
-  included on the link line before `msvcrt.lib`, otherwise Microsoft's
-  definitions of `operator new` and `operator delete` inside `msvcrt.lib` will
-  end up being used instead of libc++'s.
-
 Links
 =====
 
Index: include/__config
===================================================================
--- include/__config
+++ include/__config
@@ -524,14 +524,17 @@
 # define _LIBCPP_DLL_VIS
 # define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
 # define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
+# define _LIBCPP_OVERRIDABLE_FUNC_VIS
 #elif defined(_LIBCPP_BUILDING_LIBRARY)
 # define _LIBCPP_DLL_VIS __declspec(dllexport)
 # define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
 # define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS _LIBCPP_DLL_VIS
+# define _LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_DLL_VIS
 #else
 # define _LIBCPP_DLL_VIS __declspec(dllimport)
 # define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS _LIBCPP_DLL_VIS
 # define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
+# define _LIBCPP_OVERRIDABLE_FUNC_VIS
 #endif
 
 #define _LIBCPP_TYPE_VIS            _LIBCPP_DLL_VIS
@@ -576,6 +579,10 @@
 # define _LIBCPP_FUNC_VIS_ONLY _LIBCPP_FUNC_VIS
 #endif
 
+#ifndef _LIBCPP_OVERRIDABLE_FUNC_VIS
+# define _LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_FUNC_VIS
+#endif
+
 #ifndef _LIBCPP_EXCEPTION_ABI
 #define _LIBCPP_EXCEPTION_ABI __attribute__ ((__visibility__("default")))
 #endif
Index: include/new
===================================================================
--- include/new
+++ include/new
@@ -162,49 +162,43 @@
 
 }  // std
 
-#if defined(_WIN32) && !defined(_LIBCPP_BUILDING_LIBRARY)
-# define _LIBCPP_NEW_DELETE_VIS
-#else
-# define _LIBCPP_NEW_DELETE_VIS _LIBCPP_FUNC_VIS
-#endif
-
 #if !__has_feature(cxx_noexcept)
 #define _THROW_BAD_ALLOC throw(std::bad_alloc)
 #else
 #define _THROW_BAD_ALLOC
 #endif
 
-_LIBCPP_NEW_DELETE_VIS void* operator new(std::size_t __sz) _THROW_BAD_ALLOC;
-_LIBCPP_NEW_DELETE_VIS void* operator new(std::size_t __sz, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
-_LIBCPP_NEW_DELETE_VIS void  operator delete(void* __p) _NOEXCEPT;
-_LIBCPP_NEW_DELETE_VIS void  operator delete(void* __p, const std::nothrow_t&) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz) _THROW_BAD_ALLOC;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete(void* __p) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete(void* __p, const std::nothrow_t&) _NOEXCEPT;
 #ifndef _LIBCPP_HAS_NO_SIZED_DEALLOCATION
-_LIBCPP_NEW_DELETE_VIS void  operator delete(void* __p, std::size_t __sz) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete(void* __p, std::size_t __sz) _NOEXCEPT;
 #endif
 
-_LIBCPP_NEW_DELETE_VIS void* operator new[](std::size_t __sz) _THROW_BAD_ALLOC;
-_LIBCPP_NEW_DELETE_VIS void* operator new[](std::size_t __sz, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
-_LIBCPP_NEW_DELETE_VIS void  operator delete[](void* __p) _NOEXCEPT;
-_LIBCPP_NEW_DELETE_VIS void  operator delete[](void* __p, const std::nothrow_t&) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new[](std::size_t __sz) _THROW_BAD_ALLOC;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new[](std::size_t __sz, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete[](void* __p) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete[](void* __p, const std::nothrow_t&) _NOEXCEPT;
 #ifdef _LIBCPP_HAS_NO_SIZED_DEALLOCATION
-_LIBCPP_NEW_DELETE_VIS void  operator delete[](void* __p, std::size_t __sz) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete[](void* __p, std::size_t __sz) _NOEXCEPT;
 #endif
 
 #ifndef _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
-_LIBCPP_NEW_DELETE_VIS void* operator new(std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
-_LIBCPP_NEW_DELETE_VIS void* operator new(std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
-_LIBCPP_NEW_DELETE_VIS void  operator delete(void* __p, std::align_val_t) _NOEXCEPT;
-_LIBCPP_NEW_DELETE_VIS void  operator delete(void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new(std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete(void* __p, std::align_val_t) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete(void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
 #ifndef _LIBCPP_HAS_NO_SIZED_DEALLOCATION
-_LIBCPP_NEW_DELETE_VIS void  operator delete(void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete(void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
 #endif
 
-_LIBCPP_NEW_DELETE_VIS void* operator new[](std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
-_LIBCPP_NEW_DELETE_VIS void* operator new[](std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
-_LIBCPP_NEW_DELETE_VIS void  operator delete[](void* __p, std::align_val_t) _NOEXCEPT;
-_LIBCPP_NEW_DELETE_VIS void  operator delete[](void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new[](std::size_t __sz, std::align_val_t) _THROW_BAD_ALLOC;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void* operator new[](std::size_t __sz, std::align_val_t, const std::nothrow_t&) _NOEXCEPT _NOALIAS;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete[](void* __p, std::align_val_t) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete[](void* __p, std::align_val_t, const std::nothrow_t&) _NOEXCEPT;
 #ifndef _LIBCPP_HAS_NO_SIZED_DEALLOCATION
-_LIBCPP_NEW_DELETE_VIS void  operator delete[](void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
+_LIBCPP_OVERRIDABLE_FUNC_VIS void  operator delete[](void* __p, std::size_t __sz, std::align_val_t) _NOEXCEPT;
 #endif
 #endif
 
Index: src/new.cpp
===================================================================
--- src/new.cpp
+++ src/new.cpp
@@ -37,7 +37,7 @@
 // in this shared library, so that they can be overridden by programs
 // that define non-weak copies of the functions.
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void *
 operator new(std::size_t size) _THROW_BAD_ALLOC
 {
@@ -61,7 +61,7 @@
     return p;
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void *
 operator new(std::size_t size, std::align_val_t alignment) _THROW_BAD_ALLOC
 {
@@ -89,7 +89,7 @@
     return p;
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void*
 operator new(size_t size, const std::nothrow_t&) _NOEXCEPT
 {
@@ -108,7 +108,7 @@
     return p;
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void*
 operator new(size_t size, std::align_val_t alignment, const std::nothrow_t&) _NOEXCEPT
 {
@@ -127,21 +127,21 @@
     return p;
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void*
 operator new[](size_t size) _THROW_BAD_ALLOC
 {
     return ::operator new(size);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void*
 operator new[](size_t size, std::align_val_t alignment) _THROW_BAD_ALLOC
 {
     return ::operator new(size, alignment);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void*
 operator new[](size_t size, const std::nothrow_t&) _NOEXCEPT
 {
@@ -160,7 +160,7 @@
     return p;
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void*
 operator new[](size_t size, std::align_val_t alignment, const std::nothrow_t&) _NOEXCEPT
 {
@@ -179,7 +179,7 @@
     return p;
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void
 operator delete(void* ptr) _NOEXCEPT
 {
@@ -187,7 +187,7 @@
         ::free(ptr);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void
 operator delete(void* ptr, std::align_val_t) _NOEXCEPT
 {
@@ -195,70 +195,70 @@
         ::free(ptr);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void
 operator delete(void* ptr, const std::nothrow_t&) _NOEXCEPT
 {
     ::operator delete(ptr);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void
 operator delete(void* ptr, std::align_val_t alignment, const std::nothrow_t&) _NOEXCEPT
 {
     ::operator delete(ptr, alignment);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void
 operator delete(void* ptr, size_t) _NOEXCEPT
 {
     ::operator delete(ptr);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void
 operator delete(void* ptr, size_t, std::align_val_t alignment) _NOEXCEPT
 {
     ::operator delete(ptr, alignment);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void
 operator delete[] (void* ptr) _NOEXCEPT
 {
     ::operator delete(ptr);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void
 operator delete[] (void* ptr, std::align_val_t alignment) _NOEXCEPT
 {
     ::operator delete(ptr, alignment);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void
 operator delete[] (void* ptr, const std::nothrow_t&) _NOEXCEPT
 {
     ::operator delete[](ptr);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void
 operator delete[] (void* ptr, std::align_val_t alignment, const std::nothrow_t&) _NOEXCEPT
 {
     ::operator delete[](ptr, alignment);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void
 operator delete[] (void* ptr, size_t) _NOEXCEPT
 {
     ::operator delete[](ptr);
 }
 
-_LIBCPP_WEAK _LIBCPP_NEW_DELETE_VIS
+_LIBCPP_WEAK _LIBCPP_OVERRIDABLE_FUNC_VIS
 void
 operator delete[] (void* ptr, size_t, std::align_val_t alignment) _NOEXCEPT
 {