3 files changed, 14 insertions, 61 deletions
diff --git a/libcxx/include/__fwd/map.h b/libcxx/include/__fwd/map.h
deleted file mode 100644
index 940298d..0000000
--- a/libcxx/include/__fwd/map.h
+++ /dev/null
@@ -1,31 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef _LIBCPP___FWD_MAP_H
-#define _LIBCPP___FWD_MAP_H
-
-#include <__config>
-#include <__fwd/functional.h>
-#include <__fwd/memory.h>
-#include <__fwd/pair.h>
-
-#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
-#  pragma GCC system_header
-#endif
-
-_LIBCPP_BEGIN_NAMESPACE_STD
-
-template <class _Key, class _Tp, class _Compare = less<_Key>, class _Allocator = allocator<pair<const _Key, _Tp> > >
-class map;
-
-template <class _Key, class _Tp, class _Compare = less<_Key>, class _Allocator = allocator<pair<const _Key, _Tp> > >
-class multimap;
-
-_LIBCPP_END_NAMESPACE_STD
-
-#endif // _LIBCPP___FWD_MAP_H
diff --git a/libcxx/include/__fwd/set.h b/libcxx/include/__fwd/set.h
deleted file mode 100644
index d5ef8d5..0000000
--- a/libcxx/include/__fwd/set.h
+++ /dev/null
@@ -1,30 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef _LIBCPP___FWD_SET_H
-#define _LIBCPP___FWD_SET_H
-
-#include <__config>
-#include <__fwd/functional.h>
-#include <__fwd/memory.h>
-
-#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
-#  pragma GCC system_header
-#endif
-
-_LIBCPP_BEGIN_NAMESPACE_STD
-
-template <class _Key, class _Compare = less<_Key>, class _Allocator = allocator<_Key> >
-class set;
-
-template <class _Key, class _Compare = less<_Key>, class _Allocator = allocator<_Key> >
-class multiset;
-
-_LIBCPP_END_NAMESPACE_STD
-
-#endif // _LIBCPP___FWD_SET_H
diff --git a/libcxx/include/__fwd/tuple.h b/libcxx/include/__fwd/tuple.h
index fb922b2..dc96c03 100644
--- a/libcxx/include/__fwd/tuple.h
+++ b/libcxx/include/__fwd/tuple.h
@@ -21,12 +21,26 @@ _LIBCPP_BEGIN_NAMESPACE_STD
 template <size_t, class>
 struct tuple_element;
 
+template <size_t _Np, class _Tp>
+using __tuple_element_t _LIBCPP_NODEBUG = typename tuple_element<_Np, _Tp>::type;
+
 #ifndef _LIBCPP_CXX03_LANG
 
 template <class...>
 class tuple;
 
 template <class>
+inline const bool __is_tuple_v = false;
+
+template <class... _Tp>
+inline const bool __is_tuple_v<tuple<_Tp...>> = true;
+
+template <size_t _Ip, class... _Tp>
+struct tuple_element<_Ip, tuple<_Tp...> > {
+  using type _LIBCPP_NODEBUG = __type_pack_element<_Ip, _Tp...>;
+};
+
+template <class>
 struct tuple_size;
 
 template <size_t _Ip, class... _Tp>