Implement <filesystem>

This patch implements the <filesystem> header and uses that
to provide <experimental/filesystem>.

Unlike other standard headers, the symbols needed for <filesystem>
have not yet been placed in libc++.so. Instead they live in the
new libc++fs.a library. Users of filesystem are required to link this
library. (Also note that libc++experimental no longer contains the
definition of <experimental/filesystem>, which now requires linking libc++fs).

The reason for keeping <filesystem> out of the dylib for now is that
it's still somewhat experimental, and the possibility of requiring an
ABI breaking change is very real. In the future the symbols will likely
be moved into the dylib, or the dylib will be made to link libc++fs automagically).

Note that moving the symbols out of libc++experimental may break user builds
until they update to -lc++fs. This should be OK, because the experimental
library provides no stability guarantees. However, I plan on looking into
ways we can force libc++experimental to automagically link libc++fs.

In order to use a single implementation and set of tests for <filesystem>, it
has been placed in a special `__fs` namespace. This namespace is inline in
C++17 onward, but not before that. As such implementation is available
in C++11 onward, but no filesystem namespace is present "directly", and
as such name conflicts shouldn't occur in C++11 or C++14.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@338093 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0a692ac..cd4786e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -107,6 +107,10 @@
 cmake_dependent_option(LIBCXX_INSTALL_EXPERIMENTAL_LIBRARY
         "Install libc++experimental.a" ON
         "LIBCXX_ENABLE_EXPERIMENTAL_LIBRARY;LIBCXX_INSTALL_LIBRARY" OFF)
+cmake_dependent_option(LIBCXX_INSTALL_FILESYSTEM_LIBRARY
+        "Install libc++fs.a" ON
+        "LIBCXX_ENABLE_FILESYSTEM_LIBRARY;LIBCXX_INSTALL_LIBRARY" OFF)
+
 if (FUCHSIA)
   set(DEFAULT_ABI_VERSION 2)
 else()
diff --git a/docs/BuildingLibcxx.rst b/docs/BuildingLibcxx.rst
index 3dae2f4..d0b03c6 100644
--- a/docs/BuildingLibcxx.rst
+++ b/docs/BuildingLibcxx.rst
@@ -242,11 +242,15 @@
 
 .. option:: LIBCXX_ENABLE_FILESYSTEM:BOOL
 
-  **Default**: ``LIBCXX_ENABLE_EXPERIMENTAL_LIBRARY``
+  **Default**: ``ON``
 
-  Build filesystem as part of libc++experimental.a. This allows filesystem
-  to be disabled without turning off the entire experimental library.
+  Build filesystem as a standalone library libc++fs.a.
 
+.. option:: LIBCXX_INSTALL_FILESYSTEM_LIBRARY:BOOL
+
+  **Default**: ``LIBCXX_ENABLE_FILESYSTEM AND LIBCXX_INSTALL_LIBRARY``
+
+  Install libc++fs.a alongside libc++.
 
 .. _ABI Library Specific Options:
 
diff --git a/docs/UsingLibcxx.rst b/docs/UsingLibcxx.rst
index f54234d..e10a27c 100644
--- a/docs/UsingLibcxx.rst
+++ b/docs/UsingLibcxx.rst
@@ -49,6 +49,24 @@
   $ export LD_LIBRARY_PATH=<libcxx-install-prefix>/lib
   $ ./a.out # Searches for libc++ along LD_LIBRARY_PATH
 
+
+Using ``<filesystem>`` and libc++fs
+====================================
+
+Libc++ provides the implementation of the filesystem library in a separate
+library. Users of ``<filesystem>`` and ``<experimental/filesystem>`` are
+required to link ``-lc++fs``.
+
+.. note::
+  Prior to libc++ 7.0, users of ``<experimental/filesystem>`` were required
+  to link libc++experimental.
+
+.. warning::
+  The Filesystem library is still experimental in nature. As such normal
+  guarantees about ABI stability and backwards compatibility do not yet apply
+  to it. In the future, this restriction will be removed.
+
+
 Using libc++experimental and ``<experimental/...>``
 =====================================================
 
@@ -65,6 +83,9 @@
 :ref:`Building Libc++ <build instructions>` and
 :ref:`libc++experimental CMake Options <libc++experimental options>`.
 
+Note that as of libc++ 7.0 using the ``<experimental/filesystem>`` requires linking
+libc++fs instead of libc++experimental.
+
 Also see the `Experimental Library Implementation Status <http://libcxx.llvm.org/ts1z_status.html>`__
 page.
 
diff --git a/include/__config b/include/__config
index f659ba9..4b17fb5 100644
--- a/include/__config
+++ b/include/__config
@@ -43,6 +43,18 @@
 #  endif
 #endif
 
+#ifndef _LIBCPP_STD_VER
+#  if  __cplusplus <= 201103L
+#    define _LIBCPP_STD_VER 11
+#  elif __cplusplus <= 201402L
+#    define _LIBCPP_STD_VER 14
+#  elif __cplusplus <= 201703L
+#    define _LIBCPP_STD_VER 17
+#  else
+#    define _LIBCPP_STD_VER 18  // current year, or date of c++2a ratification
+#  endif
+#endif  // _LIBCPP_STD_VER
+
 #if defined(__ELF__)
 #  define _LIBCPP_OBJECT_FORMAT_ELF   1
 #elif defined(__MACH__)
@@ -462,6 +474,19 @@
   }
 }
 
+#if _LIBCPP_STD_VER >= 17
+#define _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM \
+  _LIBCPP_BEGIN_NAMESPACE_STD inline namespace __fs { namespace filesystem {
+#else
+#define _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM \
+  _LIBCPP_BEGIN_NAMESPACE_STD namespace __fs { namespace filesystem {
+#endif
+
+#define _LIBCPP_END_NAMESPACE_FILESYSTEM \
+  _LIBCPP_END_NAMESPACE_STD } }
+
+#define _VSTD_FS _VSTD::__fs::filesystem
+
 #if !defined(_LIBCPP_HAS_NO_ASAN) && !__has_feature(address_sanitizer)
 #define _LIBCPP_HAS_NO_ASAN
 #endif
@@ -959,18 +984,6 @@
 #define _LIBCPP_WCTYPE_IS_MASK
 #endif
 
-#ifndef _LIBCPP_STD_VER
-#  if  __cplusplus <= 201103L
-#    define _LIBCPP_STD_VER 11
-#  elif __cplusplus <= 201402L
-#    define _LIBCPP_STD_VER 14
-#  elif __cplusplus <= 201703L
-#    define _LIBCPP_STD_VER 17
-#  else
-#    define _LIBCPP_STD_VER 18  // current year, or date of c++2a ratification
-#  endif
-#endif  // _LIBCPP_STD_VER
-
 #if _LIBCPP_STD_VER > 11
 #  define _LIBCPP_DEPRECATED [[deprecated]]
 #else
diff --git a/include/experimental/__config b/include/experimental/__config
index 97c2543..55ae31b 100644
--- a/include/experimental/__config
+++ b/include/experimental/__config
@@ -52,8 +52,6 @@
 
 #define _VSTD_CORO _VSTD_EXPERIMENTAL::coroutines_v1
 
-#define _VSTD_FS ::std::experimental::filesystem::v1
-
 #define _LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL_SIMD \
     _LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL inline namespace parallelism_v2 {
 
diff --git a/include/experimental/filesystem b/include/experimental/filesystem
index dbc0359..28d8dcf 100644
--- a/include/experimental/filesystem
+++ b/include/experimental/filesystem
@@ -231,21 +231,7 @@
 */
 
 #include <experimental/__config>
-#include <cstddef>
-#include <cstdlib>
-#include <chrono>
-#include <iterator>
-#include <iosfwd>
-#include <locale>
-#include <memory>
-#include <stack>
-#include <string>
-#include <system_error>
-#include <utility>
-#include <iomanip> // for quoted
-#include <string_view>
-
-#include <__debug>
+#include <filesystem>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
@@ -260,2453 +246,7 @@
 
 _LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL_FILESYSTEM
 
-struct _FilesystemClock {
-#if !defined(_LIBCPP_HAS_NO_INT128)
-  typedef __int128_t rep;
-  typedef nano period;
-#else
-  typedef long long rep;
-  typedef nano period;
-#endif
-
-  typedef chrono::duration<rep, period> duration;
-  typedef chrono::time_point<_FilesystemClock> time_point;
-
-  static _LIBCPP_CONSTEXPR_AFTER_CXX11 const bool is_steady = false;
-
-  _LIBCPP_FUNC_VIS static time_point now() noexcept;
-
-  _LIBCPP_INLINE_VISIBILITY
-  static time_t to_time_t(const time_point& __t) noexcept {
-    typedef chrono::duration<rep> __secs;
-    return time_t(
-        chrono::duration_cast<__secs>(__t.time_since_epoch()).count());
-  }
-
-  _LIBCPP_INLINE_VISIBILITY
-  static time_point from_time_t(time_t __t) noexcept {
-    typedef chrono::duration<rep> __secs;
-    return time_point(__secs(__t));
-  }
-};
-
-typedef chrono::time_point<_FilesystemClock> file_time_type;
-
-struct _LIBCPP_TYPE_VIS space_info
-{
-  uintmax_t capacity;
-  uintmax_t free;
-  uintmax_t available;
-};
-
-enum class _LIBCPP_ENUM_VIS file_type : signed char
-{
-    none       = 0,
-    not_found  = -1,
-    regular    = 1,
-    directory  = 2,
-    symlink    = 3,
-    block      = 4,
-    character  = 5,
-    fifo       = 6,
-    socket     = 7,
-    unknown    = 8
-};
-
-enum class _LIBCPP_ENUM_VIS perms : unsigned
-{
-    none         = 0,
-
-    owner_read   = 0400,
-    owner_write  = 0200,
-    owner_exec   = 0100,
-    owner_all    = 0700,
-
-    group_read   = 040,
-    group_write  = 020,
-    group_exec   = 010,
-    group_all    = 070,
-
-    others_read  = 04,
-    others_write = 02,
-    others_exec  = 01,
-    others_all   = 07,
-
-    all          = 0777,
-
-    set_uid      = 04000,
-    set_gid      = 02000,
-    sticky_bit   = 01000,
-    mask         = 07777,
-    unknown      = 0xFFFF,
-};
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr perms operator&(perms _LHS, perms _RHS)
-{ return static_cast<perms>(static_cast<unsigned>(_LHS) & static_cast<unsigned>(_RHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr perms operator|(perms _LHS, perms _RHS)
-{ return static_cast<perms>(static_cast<unsigned>(_LHS) | static_cast<unsigned>(_RHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr perms operator^(perms _LHS, perms _RHS)
-{ return static_cast<perms>(static_cast<unsigned>(_LHS) ^ static_cast<unsigned>(_RHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr perms operator~(perms _LHS)
-{ return static_cast<perms>(~static_cast<unsigned>(_LHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline perms& operator&=(perms& _LHS, perms _RHS)
-{ return _LHS = _LHS & _RHS; }
-
-_LIBCPP_INLINE_VISIBILITY
-inline perms& operator|=(perms& _LHS, perms _RHS)
-{ return _LHS = _LHS | _RHS; }
-
-_LIBCPP_INLINE_VISIBILITY
-inline perms& operator^=(perms& _LHS, perms _RHS)
-{ return _LHS = _LHS ^ _RHS; }
-
-enum class _LIBCPP_ENUM_VIS perm_options : unsigned char {
-  replace  = 1,
-  add      = 2,
-  remove   = 4,
-  nofollow = 8
-};
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr perm_options operator&(perm_options _LHS, perm_options _RHS)
-{ return static_cast<perm_options>(static_cast<unsigned>(_LHS) & static_cast<unsigned>(_RHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr perm_options operator|(perm_options _LHS, perm_options _RHS)
-{ return static_cast<perm_options>(static_cast<unsigned>(_LHS) | static_cast<unsigned>(_RHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr perm_options operator^(perm_options _LHS, perm_options _RHS)
-{ return static_cast<perm_options>(static_cast<unsigned>(_LHS) ^ static_cast<unsigned>(_RHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr perm_options operator~(perm_options _LHS)
-{ return static_cast<perm_options>(~static_cast<unsigned>(_LHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline perm_options& operator&=(perm_options& _LHS, perm_options _RHS)
-{ return _LHS = _LHS & _RHS; }
-
-_LIBCPP_INLINE_VISIBILITY
-inline perm_options& operator|=(perm_options& _LHS, perm_options _RHS)
-{ return _LHS = _LHS | _RHS; }
-
-_LIBCPP_INLINE_VISIBILITY
-inline perm_options& operator^=(perm_options& _LHS, perm_options _RHS)
-{ return _LHS = _LHS ^ _RHS; }
-
-enum class _LIBCPP_ENUM_VIS copy_options : unsigned short
-{
-    none               = 0,
-    skip_existing      = 1,
-    overwrite_existing = 2,
-    update_existing    = 4,
-    recursive          = 8,
-    copy_symlinks      = 16,
-    skip_symlinks      = 32,
-    directories_only   = 64,
-    create_symlinks    = 128,
-    create_hard_links  = 256,
-    __in_recursive_copy = 512,
-};
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr copy_options operator&(copy_options _LHS, copy_options _RHS)
-{ return static_cast<copy_options>(static_cast<unsigned short>(_LHS) & static_cast<unsigned short>(_RHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr copy_options operator|(copy_options _LHS, copy_options _RHS)
-{ return static_cast<copy_options>(static_cast<unsigned short>(_LHS) | static_cast<unsigned short>(_RHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr copy_options operator^(copy_options _LHS, copy_options _RHS)
-{ return static_cast<copy_options>(static_cast<unsigned short>(_LHS) ^ static_cast<unsigned short>(_RHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr copy_options operator~(copy_options _LHS)
-{ return static_cast<copy_options>(~static_cast<unsigned short>(_LHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline copy_options& operator&=(copy_options& _LHS, copy_options _RHS)
-{ return _LHS = _LHS & _RHS; }
-
-_LIBCPP_INLINE_VISIBILITY
-inline copy_options& operator|=(copy_options& _LHS, copy_options _RHS)
-{ return _LHS = _LHS | _RHS; }
-
-_LIBCPP_INLINE_VISIBILITY
-inline copy_options& operator^=(copy_options& _LHS, copy_options _RHS)
-{ return _LHS = _LHS ^ _RHS; }
-
-
-enum class _LIBCPP_ENUM_VIS directory_options : unsigned char
-{
-    none                     = 0,
-    follow_directory_symlink = 1,
-    skip_permission_denied   = 2
-};
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr directory_options operator&(directory_options _LHS, directory_options _RHS)
-{ return static_cast<directory_options>(static_cast<unsigned char>(_LHS) & static_cast<unsigned char>(_RHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr directory_options operator|(directory_options _LHS, directory_options _RHS)
-{ return static_cast<directory_options>(static_cast<unsigned char>(_LHS) | static_cast<unsigned char>(_RHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr directory_options operator^(directory_options _LHS, directory_options _RHS)
-{ return static_cast<directory_options>(static_cast<unsigned char>(_LHS) ^ static_cast<unsigned char>(_RHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline constexpr directory_options operator~(directory_options _LHS)
-{ return static_cast<directory_options>(~static_cast<unsigned char>(_LHS)); }
-
-_LIBCPP_INLINE_VISIBILITY
-inline directory_options& operator&=(directory_options& _LHS, directory_options _RHS)
-{ return _LHS = _LHS & _RHS; }
-
-_LIBCPP_INLINE_VISIBILITY
-inline directory_options& operator|=(directory_options& _LHS, directory_options _RHS)
-{ return _LHS = _LHS | _RHS; }
-
-_LIBCPP_INLINE_VISIBILITY
-inline directory_options& operator^=(directory_options& _LHS, directory_options _RHS)
-{ return _LHS = _LHS ^ _RHS; }
-
-
-class _LIBCPP_TYPE_VIS file_status
-{
-public:
-    // constructors
-    _LIBCPP_INLINE_VISIBILITY
-    file_status() noexcept : file_status(file_type::none) {}
-    _LIBCPP_INLINE_VISIBILITY
-    explicit file_status(file_type __ft,
-                         perms __prms = perms::unknown) noexcept
-      : __ft_(__ft), __prms_(__prms)
-    {}
-
-    file_status(const file_status&) noexcept = default;
-    file_status(file_status&&) noexcept = default;
-
-    _LIBCPP_INLINE_VISIBILITY
-    ~file_status() {}
-
-    file_status& operator=(const file_status&) noexcept = default;
-    file_status& operator=(file_status&&) noexcept = default;
-
-    // observers
-    _LIBCPP_INLINE_VISIBILITY
-    file_type type() const noexcept {
-        return __ft_;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    perms permissions() const noexcept {
-        return __prms_;
-    }
-
-    // modifiers
-    _LIBCPP_INLINE_VISIBILITY
-    void type(file_type __ft) noexcept {
-        __ft_ = __ft;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    void permissions(perms __p) noexcept {
-        __prms_ = __p;
-    }
-private:
-    file_type __ft_;
-    perms __prms_;
-};
-
-class _LIBCPP_TYPE_VIS directory_entry;
-
-template <class _Tp> struct __can_convert_char {
-  static const bool value = false;
-};
-template <class _Tp> struct __can_convert_char<const _Tp>
-    : public __can_convert_char<_Tp> {
-};
-template <> struct __can_convert_char<char> {
-    static const bool value = true;
-    using __char_type = char;
-};
-template <> struct __can_convert_char<wchar_t>  {
-    static const bool value = true;
-    using __char_type = wchar_t;
-};
-template <> struct __can_convert_char<char16_t> {
-    static const bool value = true;
-    using __char_type = char16_t;
-};
-template <> struct __can_convert_char<char32_t> {
-    static const bool value = true;
-    using __char_type = char32_t;
-};
-
-template <class _ECharT>
-typename enable_if<__can_convert_char<_ECharT>::value, bool>::type
-__is_separator(_ECharT __e) {
-    return __e == _ECharT('/');
-};
-
-struct _NullSentinal {};
-
-template <class _Tp>
-using _Void = void;
-
-template <class _Tp, class = void>
-struct __is_pathable_string : public false_type {};
-
-template <class _ECharT, class _Traits, class _Alloc>
-struct __is_pathable_string<basic_string<_ECharT, _Traits, _Alloc>,
-                            _Void<typename __can_convert_char<_ECharT>::__char_type>>
-: public __can_convert_char<_ECharT>
-{
-    using _Str = basic_string<_ECharT, _Traits, _Alloc>;
-    using _Base = __can_convert_char<_ECharT>;
-    static _ECharT const* __range_begin(_Str const& __s) { return __s.data(); }
-    static _ECharT const* __range_end(_Str const& __s) { return __s.data() + __s.length(); }
-    static _ECharT __first_or_null(_Str const& __s) {
-        return __s.empty() ? _ECharT{} : __s[0];
-    }
-};
-
-
-template <class _ECharT, class _Traits>
-struct __is_pathable_string<basic_string_view<_ECharT, _Traits>,
-                            _Void<typename __can_convert_char<_ECharT>::__char_type>>
-: public __can_convert_char<_ECharT>
-{
-    using _Str = basic_string_view<_ECharT, _Traits>;
-    using _Base = __can_convert_char<_ECharT>;
-    static _ECharT const* __range_begin(_Str const& __s) { return __s.data(); }
-    static _ECharT const* __range_end(_Str const& __s) { return __s.data() + __s.length(); }
-    static _ECharT __first_or_null(_Str const& __s) {
-        return __s.empty() ? _ECharT{} : __s[0];
-    }
-};
-
-template <class _Source,
-          class _DS = typename decay<_Source>::type,
-          class _UnqualPtrType = typename remove_const<
-              typename remove_pointer<_DS>::type>::type,
-          bool _IsCharPtr = is_pointer<_DS>::value &&
-                            __can_convert_char<_UnqualPtrType>::value
-        >
-struct __is_pathable_char_array : false_type {};
-
-template <class _Source, class _ECharT, class _UPtr>
-struct __is_pathable_char_array<_Source, _ECharT*, _UPtr, true>
-        : __can_convert_char<typename remove_const<_ECharT>::type>
-{
-  using _Base = __can_convert_char<typename remove_const<_ECharT>::type>;
-
-  static _ECharT const* __range_begin(const _ECharT* __b) { return __b; }
-  static _ECharT const* __range_end(const _ECharT* __b)
-  {
-      using _Iter = const _ECharT*;
-      const _ECharT __sentinal = _ECharT{};
-      _Iter __e = __b;
-      for (; *__e != __sentinal; ++__e)
-          ;
-      return __e;
-  }
-
-  static _ECharT __first_or_null(const _ECharT* __b) { return *__b; }
-};
-
-template <class _Iter, bool _IsIt = __is_input_iterator<_Iter>::value, class = void>
-struct __is_pathable_iter : false_type {};
-
-template <class _Iter>
-struct __is_pathable_iter<_Iter, true,
-        _Void<typename __can_convert_char<typename iterator_traits<_Iter>::value_type>::__char_type>>
-        : __can_convert_char<typename iterator_traits<_Iter>::value_type>
-{
-  using _ECharT = typename iterator_traits<_Iter>::value_type;
-  using _Base = __can_convert_char<_ECharT>;
-
-  static _Iter         __range_begin(_Iter __b) { return __b; }
-  static _NullSentinal __range_end(_Iter)       { return _NullSentinal{}; }
-
-  static _ECharT __first_or_null(_Iter __b) { return *__b; }
-};
-
-template <class _Tp, bool _IsStringT =  __is_pathable_string<_Tp>::value,
-                     bool _IsCharIterT = __is_pathable_char_array<_Tp>::value,
-                     bool _IsIterT = !_IsCharIterT && __is_pathable_iter<_Tp>::value
-         >
-struct __is_pathable : false_type {
-  static_assert(!_IsStringT && !_IsCharIterT && !_IsIterT, "Must all be false");
-};
-
-template <class _Tp>
-struct __is_pathable<_Tp, true, false, false> : __is_pathable_string<_Tp> {};
-
-
-template <class _Tp>
-struct __is_pathable<_Tp, false, true, false> : __is_pathable_char_array<_Tp> {};
-
-
-template <class _Tp>
-struct __is_pathable<_Tp, false, false, true> : __is_pathable_iter<_Tp> {};
-
-
-template <class _ECharT>
-struct _PathCVT {
-    static_assert(__can_convert_char<_ECharT>::value, "Char type not convertible");
-
-    typedef __narrow_to_utf8<sizeof(_ECharT)*__CHAR_BIT__> _Narrower;
-
-    static void __append_range(string& __dest, _ECharT const* __b, _ECharT const* __e)  {
-        _Narrower()(back_inserter(__dest), __b, __e);
-    }
-
-    template <class _Iter>
-    static void __append_range(string& __dest, _Iter __b, _Iter __e) {
-        static_assert(!is_same<_Iter, _ECharT*>::value, "Call const overload");
-        if (__b == __e) return;
-        basic_string<_ECharT> __tmp(__b, __e);
-        _Narrower()(back_inserter(__dest), __tmp.data(),
-                    __tmp.data() + __tmp.length());
-    }
-
-    template <class _Iter>
-    static void __append_range(string& __dest, _Iter __b, _NullSentinal) {
-        static_assert(!is_same<_Iter, _ECharT*>::value, "Call const overload");
-        const _ECharT __sentinal = _ECharT{};
-        if (*__b == __sentinal) return;
-        basic_string<_ECharT> __tmp;
-        for (; *__b != __sentinal; ++__b)
-            __tmp.push_back(*__b);
-        _Narrower()(back_inserter(__dest), __tmp.data(),
-                    __tmp.data() + __tmp.length());
-    }
-
-    template <class _Source>
-    static void __append_source(string& __dest, _Source const& __s)
-    {
-        using _Traits = __is_pathable<_Source>;
-        __append_range(__dest, _Traits::__range_begin(__s), _Traits::__range_end(__s));
-    }
-};
-
-template <>
-struct _PathCVT<char> {
-
-    template <class _Iter>
-    static typename enable_if<
-        __is_exactly_input_iterator<_Iter>::value
-    >::type __append_range(string& __dest, _Iter __b, _Iter __e) {
-        for (; __b != __e; ++__b)
-            __dest.push_back(*__b);
-    }
-
-    template <class _Iter>
-    static typename enable_if<
-        __is_forward_iterator<_Iter>::value
-    >::type __append_range(string& __dest, _Iter __b, _Iter __e) {
-        __dest.__append_forward_unsafe(__b, __e);
-    }
-
-    template <class _Iter>
-    static void __append_range(string& __dest, _Iter __b, _NullSentinal) {
-        const char __sentinal = char{};
-        for (; *__b != __sentinal; ++__b)
-            __dest.push_back(*__b);
-    }
-
-    template <class _Source>
-    static void __append_source(string& __dest, _Source const& __s)
-    {
-        using _Traits = __is_pathable<_Source>;
-        __append_range(__dest, _Traits::__range_begin(__s),
-                               _Traits::__range_end(__s));
-    }
-};
-
-
-class _LIBCPP_TYPE_VIS path
-{
-    template <class _SourceOrIter, class _Tp = path&>
-    using _EnableIfPathable = typename
-        enable_if<__is_pathable<_SourceOrIter>::value, _Tp>::type;
-
-    template <class _Tp>
-    using _SourceChar = typename __is_pathable<_Tp>::__char_type;
-
-    template <class _Tp>
-    using _SourceCVT = _PathCVT<_SourceChar<_Tp>>;
-
-public:
-    typedef char value_type;
-    typedef basic_string<value_type> string_type;
-    typedef _VSTD::string_view __string_view;
-    static constexpr value_type preferred_separator = '/';
-
-    enum class _LIBCPP_ENUM_VIS format : unsigned char {
-      auto_format,
-      native_format,
-      generic_format
-    };
-
-    // constructors and destructor
-    _LIBCPP_INLINE_VISIBILITY path() noexcept {}
-    _LIBCPP_INLINE_VISIBILITY path(const path& __p)      : __pn_(__p.__pn_) {}
-    _LIBCPP_INLINE_VISIBILITY path(path&& __p) noexcept : __pn_(_VSTD::move(__p.__pn_)) {}
-
-    _LIBCPP_INLINE_VISIBILITY
-    path(string_type&& __s, format = format::auto_format) noexcept
-        : __pn_(_VSTD::move(__s)) {}
-
-    template <
-        class _Source,
-        class = _EnableIfPathable<_Source, void>
-        >
-    path(const _Source& __src, format = format::auto_format) {
-        _SourceCVT<_Source>::__append_source(__pn_, __src);
-    }
-
-    template <class _InputIt>
-    path(_InputIt __first, _InputIt __last, format = format::auto_format) {
-        typedef typename iterator_traits<_InputIt>::value_type _ItVal;
-        _PathCVT<_ItVal>::__append_range(__pn_, __first, __last);
-    }
-
-    // TODO Implement locale conversions.
-    template <class _Source,
-              class = _EnableIfPathable<_Source, void>
-             >
-        path(const _Source& __src, const locale& __loc,
-             format = format::auto_format);
-    template <class _InputIt>
-        path(_InputIt __first, _InputIt _last, const locale& __loc,
-             format = format::auto_format);
-
-    _LIBCPP_INLINE_VISIBILITY
-    ~path() = default;
-
-    // assignments
-    _LIBCPP_INLINE_VISIBILITY
-    path& operator=(const path& __p) {
-        __pn_ = __p.__pn_;
-        return *this;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    path& operator=(path&& __p) noexcept {
-        __pn_ = _VSTD::move(__p.__pn_);
-        return *this;
-    }
-
-    template <class = void>
-    _LIBCPP_INLINE_VISIBILITY
-    path& operator=(string_type&& __s) noexcept {
-        __pn_ = _VSTD::move(__s);
-        return *this;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    path& assign(string_type&& __s) noexcept {
-        __pn_ = _VSTD::move(__s);
-        return *this;
-    }
-
-    template <class _Source>
-    _LIBCPP_INLINE_VISIBILITY
-    _EnableIfPathable<_Source>
-    operator=(const _Source& __src)
-    { return this->assign(__src); }
-
-
-    template <class _Source>
-    _EnableIfPathable<_Source>
-    assign(const _Source& __src) {
-        __pn_.clear();
-        _SourceCVT<_Source>::__append_source(__pn_, __src);
-        return *this;
-    }
-
-    template <class _InputIt>
-    path& assign(_InputIt __first, _InputIt __last) {
-        typedef typename iterator_traits<_InputIt>::value_type _ItVal;
-        __pn_.clear();
-        _PathCVT<_ItVal>::__append_range(__pn_, __first, __last);
-        return *this;
-    }
-
-private:
-    template <class _ECharT>
-    static bool __source_is_absolute(_ECharT __first_or_null) {
-        return __is_separator(__first_or_null);
-    }
-
-public:
-    // appends
-    path& operator/=(const path& __p) {
-        if (__p.is_absolute()) {
-          __pn_ = __p.__pn_;
-          return *this;
-        }
-        if (has_filename())
-          __pn_ += preferred_separator;
-        __pn_ += __p.native();
-        return *this;
-    }
-
-    // FIXME: Use _LIBCPP_DIAGNOSE_WARNING to produce a diagnostic when __src
-    // is known at compile time to be "/' since the user almost certainly intended
-    // to append a separator instead of overwriting the path with "/"
-    template <class _Source>
-    _LIBCPP_INLINE_VISIBILITY
-    _EnableIfPathable<_Source>
-    operator/=(const _Source& __src) {
-        return this->append(__src);
-    }
-
-    template <class _Source>
-    _EnableIfPathable<_Source>
-    append(const _Source& __src) {
-        using _Traits = __is_pathable<_Source>;
-        using _CVT = _PathCVT<_SourceChar<_Source>>;
-        if (__source_is_absolute(_Traits::__first_or_null(__src)))
-          __pn_.clear();
-        else if (has_filename())
-          __pn_ += preferred_separator;
-        _CVT::__append_source(__pn_, __src);
-        return *this;
-    }
-
-    template <class _InputIt>
-    path& append(_InputIt __first, _InputIt __last) {
-        typedef typename iterator_traits<_InputIt>::value_type _ItVal;
-        static_assert(__can_convert_char<_ItVal>::value, "Must convertible");
-        using _CVT = _PathCVT<_ItVal>;
-        if (__first != __last && __source_is_absolute(*__first))
-          __pn_.clear();
-        else if (has_filename())
-          __pn_ += preferred_separator;
-        _CVT::__append_range(__pn_, __first, __last);
-        return *this;
-    }
-
-    // concatenation
-    _LIBCPP_INLINE_VISIBILITY
-    path& operator+=(const path& __x) {
-        __pn_ += __x.__pn_;
-        return *this;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    path& operator+=(const string_type& __x) {
-        __pn_ += __x;
-        return *this;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    path& operator+=(__string_view __x) {
-        __pn_ += __x;
-        return *this;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    path& operator+=(const value_type* __x) {
-        __pn_ += __x;
-        return *this;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    path& operator+=(value_type __x) {
-        __pn_ += __x;
-        return *this;
-    }
-
-    template <class _ECharT>
-    typename enable_if<__can_convert_char<_ECharT>::value, path&>::type
-    operator+=(_ECharT __x)
-    {
-        basic_string<_ECharT> __tmp;
-        __tmp += __x;
-        _PathCVT<_ECharT>::__append_source(__pn_, __tmp);
-        return *this;
-    }
-
-    template <class _Source>
-    _EnableIfPathable<_Source>
-    operator+=(const _Source& __x) {
-       return this->concat(__x);
-    }
-
-    template <class _Source>
-    _EnableIfPathable<_Source>
-    concat(const _Source& __x) {
-         _SourceCVT<_Source>::__append_source(__pn_, __x);
-        return *this;
-    }
-
-    template <class _InputIt>
-    path& concat(_InputIt __first, _InputIt __last) {
-        typedef typename iterator_traits<_InputIt>::value_type _ItVal;
-        _PathCVT<_ItVal>::__append_range(__pn_, __first, __last);
-        return *this;
-    }
-
-    // modifiers
-    _LIBCPP_INLINE_VISIBILITY
-    void clear() noexcept {
-        __pn_.clear();
-    }
-
-    path& make_preferred() { return *this; }
-
-    _LIBCPP_INLINE_VISIBILITY
-    path& remove_filename() {
-      auto __fname = __filename();
-      if (!__fname.empty())
-        __pn_.erase(__fname.data() - __pn_.data());
-      return *this;
-    }
-
-    path& replace_filename(const path& __replacement) {
-        remove_filename();
-        return (*this /= __replacement);
-    }
-
-    path& replace_extension(const path& __replacement = path());
-
-    _LIBCPP_INLINE_VISIBILITY
-    void  swap(path& __rhs) noexcept {
-        __pn_.swap(__rhs.__pn_);
-    }
-
-    // private helper to allow reserving memory in the path
-    _LIBCPP_INLINE_VISIBILITY
-    void __reserve(size_t __s) { __pn_.reserve(__s); }
-
-    // native format observers
-    _LIBCPP_INLINE_VISIBILITY
-    const string_type& native() const noexcept {
-        return __pn_;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    const value_type* c_str() const noexcept { return __pn_.c_str(); }
-
-    _LIBCPP_INLINE_VISIBILITY operator string_type() const { return __pn_;  }
-
-    template <class _ECharT, class _Traits = char_traits<_ECharT>,
-              class _Allocator = allocator<_ECharT> >
-    basic_string<_ECharT, _Traits, _Allocator>
-    string(const _Allocator& __a = _Allocator()) const {
-        using _CVT = __widen_from_utf8<sizeof(_ECharT)*__CHAR_BIT__>;
-        using _Str = basic_string<_ECharT, _Traits, _Allocator>;
-        _Str __s(__a);
-        __s.reserve(__pn_.size());
-        _CVT()(back_inserter(__s), __pn_.data(), __pn_.data() + __pn_.size());
-        return __s;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY std::string    string()    const { return __pn_; }
-    _LIBCPP_INLINE_VISIBILITY std::wstring   wstring()   const { return string<wchar_t>(); }
-    _LIBCPP_INLINE_VISIBILITY std::string    u8string()  const { return __pn_; }
-    _LIBCPP_INLINE_VISIBILITY std::u16string u16string() const { return string<char16_t>(); }
-    _LIBCPP_INLINE_VISIBILITY std::u32string u32string() const { return string<char32_t>(); }
-
-    // generic format observers
-    template <class _ECharT, class _Traits = char_traits<_ECharT>,
-              class _Allocator = allocator<_ECharT>
-    >
-    basic_string<_ECharT, _Traits, _Allocator>
-    generic_string(const _Allocator& __a = _Allocator()) const {
-        return string<_ECharT, _Traits, _Allocator>(__a);
-    }
-
-    std::string    generic_string()    const { return __pn_; }
-    std::wstring   generic_wstring()   const { return string<wchar_t>(); }
-    std::string    generic_u8string()  const { return __pn_; }
-    std::u16string generic_u16string() const { return string<char16_t>(); }
-    std::u32string generic_u32string() const { return string<char32_t>(); }
-
-private:
-    int __compare(__string_view) const;
-    __string_view __root_name() const;
-    __string_view __root_directory() const;
-    __string_view __root_path_raw() const;
-    __string_view __relative_path() const;
-    __string_view __parent_path() const;
-    __string_view __filename() const;
-    __string_view __stem() const;
-    __string_view __extension() const;
-
-public:
-    // compare
-    _LIBCPP_INLINE_VISIBILITY int compare(const path& __p) const noexcept { return __compare(__p.__pn_);}
-    _LIBCPP_INLINE_VISIBILITY int compare(const string_type& __s) const { return __compare(__s); }
-    _LIBCPP_INLINE_VISIBILITY int compare(__string_view __s) const { return __compare(__s); }
-    _LIBCPP_INLINE_VISIBILITY int compare(const value_type* __s) const  { return __compare(__s); }
-
-    // decomposition
-    _LIBCPP_INLINE_VISIBILITY path root_name()      const { return  string_type(__root_name()); }
-    _LIBCPP_INLINE_VISIBILITY path root_directory() const { return  string_type(__root_directory()); }
-    _LIBCPP_INLINE_VISIBILITY path root_path()      const { return root_name().append(string_type(__root_directory())); }
-    _LIBCPP_INLINE_VISIBILITY path relative_path()  const { return string_type(__relative_path()); }
-    _LIBCPP_INLINE_VISIBILITY path parent_path()    const { return string_type(__parent_path()); }
-    _LIBCPP_INLINE_VISIBILITY path filename()       const { return string_type(__filename()); }
-    _LIBCPP_INLINE_VISIBILITY path stem()           const { return string_type(__stem());}
-    _LIBCPP_INLINE_VISIBILITY path extension()      const { return string_type(__extension()); }
-
-    // query
-    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
-    bool empty() const noexcept { return __pn_.empty(); }
-
-    _LIBCPP_INLINE_VISIBILITY bool has_root_name()      const { return !__root_name().empty(); }
-    _LIBCPP_INLINE_VISIBILITY bool has_root_directory() const { return !__root_directory().empty(); }
-    _LIBCPP_INLINE_VISIBILITY bool has_root_path()      const { return !__root_path_raw().empty(); }
-    _LIBCPP_INLINE_VISIBILITY bool has_relative_path()  const { return !__relative_path().empty(); }
-    _LIBCPP_INLINE_VISIBILITY bool has_parent_path()    const { return !__parent_path().empty(); }
-    _LIBCPP_INLINE_VISIBILITY bool has_filename()       const { return !__filename().empty(); }
-    _LIBCPP_INLINE_VISIBILITY bool has_stem()           const { return !__stem().empty(); }
-    _LIBCPP_INLINE_VISIBILITY bool has_extension()      const { return !__extension().empty(); }
-
-    _LIBCPP_INLINE_VISIBILITY bool is_absolute()        const { return has_root_directory(); }
-    _LIBCPP_INLINE_VISIBILITY bool is_relative()        const { return !is_absolute(); }
-
-    // relative paths
-    path lexically_normal() const;
-    path lexically_relative(const path& __base) const;
-
-    _LIBCPP_INLINE_VISIBILITY path lexically_proximate(const path& __base) const {
-      path __result = this->lexically_relative(__base);
-      if (__result.native().empty())
-        return *this;
-      return __result;
-    }
-
-    // iterators
-    class _LIBCPP_TYPE_VIS iterator;
-    typedef iterator const_iterator;
-
-    iterator begin() const;
-    iterator end() const;
-
-
-    template <class _CharT, class _Traits>
-    _LIBCPP_INLINE_VISIBILITY
-    friend typename enable_if<is_same<_CharT, char>::value &&
-                       is_same<_Traits, char_traits<char>>::value,
-                       basic_ostream<_CharT, _Traits>&
-    >::type
-    operator<<(basic_ostream<_CharT, _Traits>& __os, const path& __p) {
-        __os << std::__quoted(__p.native());
-        return __os;
-    }
-
-    template <class _CharT, class _Traits>
-    _LIBCPP_INLINE_VISIBILITY
-    friend typename enable_if<!is_same<_CharT, char>::value ||
-                       !is_same<_Traits, char_traits<char>>::value,
-                       basic_ostream<_CharT, _Traits>&
-    >::type
-    operator<<(basic_ostream<_CharT, _Traits>& __os, const path& __p) {
-        __os << std::__quoted(__p.string<_CharT, _Traits>());
-        return __os;
-    }
-
-    template <class _CharT, class _Traits>
-    _LIBCPP_INLINE_VISIBILITY
-    friend basic_istream<_CharT, _Traits>&
-    operator>>(basic_istream<_CharT, _Traits>& __is, path& __p)
-    {
-        basic_string<_CharT, _Traits> __tmp;
-        __is >> __quoted(__tmp);
-        __p = __tmp;
-        return __is;
-    }
-
-private:
-    inline _LIBCPP_INLINE_VISIBILITY
-    path& __assign_view(__string_view const& __s) noexcept { __pn_ = string_type(__s); return *this; }
-    string_type __pn_;
-};
-
-inline _LIBCPP_INLINE_VISIBILITY
-void swap(path& __lhs, path& __rhs) noexcept {
-    __lhs.swap(__rhs);
-}
-
-_LIBCPP_FUNC_VIS
-size_t hash_value(const path& __p) noexcept;
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool operator==(const path& __lhs, const path& __rhs) noexcept
-{ return __lhs.compare(__rhs) == 0; }
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool operator!=(const path& __lhs, const path& __rhs) noexcept
-{ return __lhs.compare(__rhs) != 0; }
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool operator<(const path& __lhs, const path& __rhs) noexcept
-{ return __lhs.compare(__rhs) < 0; }
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool operator<=(const path& __lhs, const path& __rhs) noexcept
-{ return __lhs.compare(__rhs) <= 0; }
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool operator>(const path& __lhs, const path& __rhs) noexcept
-{ return __lhs.compare(__rhs) > 0; }
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool operator>=(const path& __lhs, const path& __rhs) noexcept
-{ return __lhs.compare(__rhs) >= 0; }
-
-inline _LIBCPP_INLINE_VISIBILITY
-path operator/(const path& __lhs, const path& __rhs) {
-    path __result(__lhs);
-    __result /= __rhs;
-    return __result;
-}
-
-template <class _Source>
-_LIBCPP_INLINE_VISIBILITY
-typename enable_if<__is_pathable<_Source>::value, path>::type
-u8path(const _Source& __s){
-    static_assert(is_same<typename __is_pathable<_Source>::__char_type, char>::value,
-        "u8path(Source const&) requires Source have a character type of type 'char'");
-    return path(__s);
-}
-
-template <class _InputIt>
-_LIBCPP_INLINE_VISIBILITY
-typename enable_if<__is_pathable<_InputIt>::value, path>::type
-u8path(_InputIt __f, _InputIt __l) {
-    static_assert(is_same<typename __is_pathable<_InputIt>::__char_type, char>::value,
-        "u8path(Iter, Iter) requires Iter have a value_type of type 'char'");
-    return path(__f, __l);
-}
-
-class _LIBCPP_TYPE_VIS path::iterator
-{
-public:
-    enum _ParserState : unsigned char {
-      _Singular,
-      _BeforeBegin,
-      _InRootName,
-      _InRootDir,
-      _InFilenames,
-      _InTrailingSep,
-      _AtEnd
-    };
-
-public:
-    typedef bidirectional_iterator_tag iterator_category;
-
-    typedef path                       value_type;
-    typedef std::ptrdiff_t             difference_type;
-    typedef const path*                pointer;
-    typedef const path&                reference;
-
-    typedef void __stashing_iterator_tag; // See reverse_iterator and __is_stashing_iterator
-
-public:
-    _LIBCPP_INLINE_VISIBILITY
-    iterator() : __stashed_elem_(), __path_ptr_(nullptr),
-                 __entry_(), __state_(_Singular) {}
-
-    iterator(const iterator&) = default;
-    ~iterator() = default;
-
-    iterator& operator=(const iterator&) = default;
-
-    _LIBCPP_INLINE_VISIBILITY
-    reference operator*() const {
-        return __stashed_elem_;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    pointer operator->() const {
-        return &__stashed_elem_;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator& operator++() {
-        _LIBCPP_ASSERT(__state_ != _Singular,
-                       "attempting to increment a singular iterator");
-        _LIBCPP_ASSERT(__state_ != _AtEnd,
-                      "attempting to increment the end iterator");
-        return __increment();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator operator++(int) {
-        iterator __it(*this);
-        this->operator++();
-        return __it;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator& operator--() {
-        _LIBCPP_ASSERT(__state_ != _Singular,
-                       "attempting to decrement a singular iterator");
-        _LIBCPP_ASSERT(__entry_.data() != __path_ptr_->native().data(),
-                       "attempting to decrement the begin iterator");
-        return __decrement();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator operator--(int) {
-        iterator __it(*this);
-        this->operator--();
-        return __it;
-    }
-
-private:
-    friend class path;
-
-    inline _LIBCPP_INLINE_VISIBILITY
-    friend bool operator==(const iterator&, const iterator&);
-
-    iterator& __increment();
-    iterator& __decrement();
-
-    path __stashed_elem_;
-    const path* __path_ptr_;
-    path::__string_view __entry_;
-    _ParserState __state_;
-};
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool operator==(const path::iterator& __lhs, const path::iterator& __rhs) {
-    return __lhs.__path_ptr_ == __rhs.__path_ptr_ &&
-           __lhs.__entry_.data() == __rhs.__entry_.data();
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool operator!=(const path::iterator& __lhs, const path::iterator& __rhs) {
-    return !(__lhs == __rhs);
-}
-
-class _LIBCPP_EXCEPTION_ABI filesystem_error : public system_error
-{
-public:
-    _LIBCPP_INLINE_VISIBILITY
-    filesystem_error(const string& __what, error_code __ec)
-        : system_error(__ec, __what),
-          __storage_(make_shared<_Storage>(path(), path())) {
-      __create_what(0);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    filesystem_error(const string& __what, const path& __p1, error_code __ec)
-        : system_error(__ec, __what),
-          __storage_(make_shared<_Storage>(__p1, path())) {
-      __create_what(1);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    filesystem_error(const string& __what, const path& __p1, const path& __p2,
-                     error_code __ec)
-        : system_error(__ec, __what),
-          __storage_(make_shared<_Storage>(__p1, __p2)) {
-      __create_what(2);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    const path& path1() const noexcept { return __storage_->__p1_; }
-
-    _LIBCPP_INLINE_VISIBILITY
-    const path& path2() const noexcept { return __storage_->__p2_; }
-
-    ~filesystem_error() override; // key function
-
-    _LIBCPP_INLINE_VISIBILITY
-    const char* what() const noexcept override {
-      return __storage_->__what_.c_str();
-    }
-
-    _LIBCPP_FUNC_VIS
-    void __create_what(int __num_paths);
-
-  private:
-    struct _Storage {
-      _LIBCPP_INLINE_VISIBILITY
-      _Storage(const path& __p1, const path& __p2) : __p1_(__p1), __p2_(__p2) {}
-
-      path __p1_;
-      path __p2_;
-      string __what_;
-    };
-    shared_ptr<_Storage> __storage_;
-};
-
-template <class... _Args>
-_LIBCPP_NORETURN inline _LIBCPP_INLINE_VISIBILITY
-#ifndef _LIBCPP_NO_EXCEPTIONS
-void __throw_filesystem_error(_Args && ...__args)
-{
-    throw filesystem_error(std::forward<_Args>(__args)...);
-}
-#else
-void __throw_filesystem_error(_Args&&...)
-{
-    _VSTD::abort();
-}
-#endif
-
-// operational functions
-
-_LIBCPP_FUNC_VIS
-path __absolute(const path&, error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-path __canonical(const path&, error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-void __copy(const path& __from, const path& __to, copy_options __opt,
-        error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-bool __copy_file(const path& __from, const path& __to, copy_options __opt,
-        error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-void __copy_symlink(const path& __existing_symlink, const path& __new_symlink,
-        error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-bool __create_directories(const path& p, error_code *ec=nullptr);
-_LIBCPP_FUNC_VIS
-bool __create_directory(const path& p, error_code *ec=nullptr);
-_LIBCPP_FUNC_VIS
-bool __create_directory(const path& p, const path & attributes,
-        error_code *ec=nullptr);
-_LIBCPP_FUNC_VIS
-void __create_directory_symlink(const path& __to, const path& __new_symlink,
-        error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-void __create_hard_link(const path& __to, const path& __new_hard_link,
-        error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-void __create_symlink(const path& __to, const path& __new_symlink,
-        error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-path __current_path(error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-void __current_path(const path&, error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-bool __equivalent(const path&, const path&, error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-uintmax_t __file_size(const path&, error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-uintmax_t __hard_link_count(const path&, error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-bool __fs_is_empty(const path& p, error_code *ec=nullptr);
-_LIBCPP_FUNC_VIS
-file_time_type __last_write_time(const path& p, error_code *ec=nullptr);
-_LIBCPP_FUNC_VIS
-void __last_write_time(const path& p, file_time_type new_time,
-        error_code *ec=nullptr);
-_LIBCPP_FUNC_VIS
-void __permissions(const path&, perms, perm_options, error_code* = nullptr);
-_LIBCPP_FUNC_VIS
-path __read_symlink(const path& p, error_code *ec=nullptr);
-_LIBCPP_FUNC_VIS
-bool __remove(const path& p, error_code *ec=nullptr);
-_LIBCPP_FUNC_VIS
-uintmax_t __remove_all(const path& p, error_code *ec=nullptr);
-_LIBCPP_FUNC_VIS
-void __rename(const path& from, const path& to, error_code *ec=nullptr);
-_LIBCPP_FUNC_VIS
-void __resize_file(const path& p, uintmax_t size, error_code *ec=nullptr);
-_LIBCPP_FUNC_VIS
-space_info __space(const path&, error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-file_status __status(const path&, error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-file_status __symlink_status(const path&, error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-path __system_complete(const path&, error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-path __temp_directory_path(error_code *__ec=nullptr);
-_LIBCPP_FUNC_VIS
-path __weakly_canonical(path const& __p, error_code *__ec=nullptr);
-
-inline _LIBCPP_INLINE_VISIBILITY
-path current_path() {
-    return __current_path();
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path current_path(error_code& __ec) {
-    return __current_path(&__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void current_path(const path& __p) {
-    __current_path(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void current_path(const path& __p, error_code& __ec) noexcept {
-    __current_path(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path absolute(const path& __p) {
-  return __absolute(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path absolute(const path& __p, error_code &__ec) {
-  return __absolute(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path canonical(const path& __p) {
-    return __canonical(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path canonical(const path& __p, error_code& __ec) {
-    return __canonical(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void copy(const path& __from, const path& __to) {
-    __copy(__from, __to, copy_options::none);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void copy(const path& __from, const path& __to, error_code& __ec) {
-    __copy(__from, __to, copy_options::none, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void copy(const path& __from, const path& __to, copy_options __opt) {
-    __copy(__from, __to, __opt);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void copy(const path& __from, const path& __to,
-          copy_options __opt, error_code& __ec) {
-    __copy(__from, __to, __opt, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool copy_file(const path& __from, const path& __to) {
-    return __copy_file(__from, __to, copy_options::none);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool copy_file(const path& __from, const path& __to, error_code& __ec) {
-    return __copy_file(__from, __to, copy_options::none, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool copy_file(const path& __from, const path& __to, copy_options __opt) {
-    return __copy_file(__from, __to, __opt);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool copy_file(const path& __from, const path& __to,
-               copy_options __opt, error_code& __ec){
-    return __copy_file(__from, __to, __opt, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void copy_symlink(const path& __existing, const path& __new) {
-    __copy_symlink(__existing, __new);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void copy_symlink(const path& __ext, const path& __new, error_code& __ec) noexcept {
-    __copy_symlink(__ext, __new, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool create_directories(const path& __p) {
-    return __create_directories(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool create_directories(const path& __p, error_code& __ec) {
-    return __create_directories(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool create_directory(const path& __p) {
-    return __create_directory(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool create_directory(const path& __p, error_code& __ec) noexcept {
-    return __create_directory(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool create_directory(const path& __p, const path& __attrs) {
-    return __create_directory(__p, __attrs);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool create_directory(const path& __p, const path& __attrs, error_code& __ec) noexcept {
-    return __create_directory(__p, __attrs, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void create_directory_symlink(const path& __to, const path& __new) {
-    __create_directory_symlink(__to, __new);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void create_directory_symlink(const path& __to, const path& __new,
-                              error_code& __ec) noexcept {
-    __create_directory_symlink(__to, __new, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void create_hard_link(const path& __to, const path& __new) {
-    __create_hard_link(__to, __new);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void create_hard_link(const path& __to, const path& __new, error_code& __ec) noexcept {
-    __create_hard_link(__to, __new, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void create_symlink(const path& __to, const path& __new) {
-    __create_symlink(__to, __new);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void create_symlink(const path& __to, const path& __new,
-                    error_code& __ec) noexcept {
-    return __create_symlink(__to, __new, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool status_known(file_status __s) noexcept {
-    return __s.type() != file_type::none;
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool exists(file_status __s) noexcept {
-    return status_known(__s) && __s.type() != file_type::not_found;
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool exists(const path& __p) {
-    return exists(__status(__p));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool exists(const path& __p, error_code& __ec) noexcept {
-    auto __s = __status(__p, &__ec);
-    if (status_known(__s)) __ec.clear();
-    return exists(__s);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool equivalent(const path& __p1, const path& __p2) {
-    return __equivalent(__p1, __p2);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool equivalent(const path& __p1, const path& __p2, error_code& __ec) noexcept {
-    return __equivalent(__p1, __p2, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-uintmax_t file_size(const path& __p) {
-    return __file_size(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-uintmax_t file_size(const path& __p, error_code& __ec) noexcept {
-    return __file_size(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-uintmax_t hard_link_count(const path& __p) {
-    return __hard_link_count(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-uintmax_t hard_link_count(const path& __p, error_code& __ec) noexcept {
-    return __hard_link_count(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_block_file(file_status __s) noexcept {
-    return __s.type() == file_type::block;
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_block_file(const path& __p) {
-    return is_block_file(__status(__p));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_block_file(const path& __p, error_code& __ec) noexcept {
-    return is_block_file(__status(__p, &__ec));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_character_file(file_status __s) noexcept {
-    return __s.type() == file_type::character;
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_character_file(const path& __p) {
-    return is_character_file(__status(__p));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_character_file(const path& __p, error_code& __ec) noexcept {
-    return is_character_file(__status(__p, &__ec));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_directory(file_status __s) noexcept {
-    return __s.type() == file_type::directory;
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_directory(const path& __p) {
-    return is_directory(__status(__p));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_directory(const path& __p, error_code& __ec) noexcept {
-    return is_directory(__status(__p, &__ec));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_empty(const path& __p) {
-    return __fs_is_empty(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_empty(const path& __p, error_code& __ec) {
-    return __fs_is_empty(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_fifo(file_status __s) noexcept {
-    return __s.type() == file_type::fifo;
-}
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_fifo(const path& __p) {
-    return is_fifo(__status(__p));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_fifo(const path& __p, error_code& __ec) noexcept {
-    return is_fifo(__status(__p, &__ec));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_regular_file(file_status __s) noexcept {
-    return __s.type() == file_type::regular;
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_regular_file(const path& __p) {
-    return is_regular_file(__status(__p));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_regular_file(const path& __p, error_code& __ec) noexcept {
-    return is_regular_file(__status(__p, &__ec));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_socket(file_status __s) noexcept {
-    return __s.type() == file_type::socket;
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_socket(const path& __p) {
-    return is_socket(__status(__p));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_socket(const path& __p, error_code& __ec) noexcept {
-    return is_socket(__status(__p, &__ec));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_symlink(file_status __s) noexcept {
-    return __s.type() == file_type::symlink;
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_symlink(const path& __p) {
-    return is_symlink(__symlink_status(__p));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_symlink(const path& __p, error_code& __ec) noexcept {
-    return is_symlink(__symlink_status(__p, &__ec));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_other(file_status __s) noexcept {
-    return exists(__s)
-        && !is_regular_file(__s) && !is_directory(__s) && !is_symlink(__s);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_other(const path& __p) {
-    return is_other(__status(__p));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool is_other(const path& __p, error_code& __ec) noexcept {
-    return is_other(__status(__p, &__ec));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-file_time_type last_write_time(const path& __p) {
-    return __last_write_time(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-file_time_type last_write_time(const path& __p, error_code& __ec) noexcept {
-    return __last_write_time(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void last_write_time(const path& __p, file_time_type __t) {
-    __last_write_time(__p, __t);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void last_write_time(const path& __p, file_time_type __t, error_code& __ec) noexcept {
-    __last_write_time(__p, __t, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void permissions(const path& __p, perms __prms,
-                 perm_options __opts = perm_options::replace) {
-    __permissions(__p, __prms, __opts);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void permissions(const path& __p, perms __prms, error_code& __ec) noexcept {
-    __permissions(__p, __prms, perm_options::replace, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void permissions(const path& __p, perms __prms, perm_options __opts,
-                 error_code& __ec)  {
-    __permissions(__p, __prms, __opts, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path proximate(const path& __p, const path& __base, error_code& __ec) {
-   path __tmp = __weakly_canonical(__p, &__ec);
-  if (__ec)
-    return {};
-  path __tmp_base = __weakly_canonical(__base, &__ec);
-  if (__ec)
-    return {};
-  return __tmp.lexically_proximate(__tmp_base);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path proximate(const path& __p, error_code& __ec) {
-  return proximate(__p, current_path(), __ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path proximate(const path& __p, const path& __base = current_path()) {
-  return __weakly_canonical(__p).lexically_proximate(__weakly_canonical(__base));
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path read_symlink(const path& __p) {
-    return __read_symlink(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path read_symlink(const path& __p, error_code& __ec) {
-    return __read_symlink(__p, &__ec);
-}
-
-
-inline _LIBCPP_INLINE_VISIBILITY
-path relative(const path& __p, const path& __base, error_code& __ec) {
-  path __tmp = __weakly_canonical(__p, &__ec);
-  if (__ec)
-    return path();
-  path __tmpbase = __weakly_canonical(__base, &__ec);
-  if (__ec)
-    return path();
-  return __tmp.lexically_relative(__tmpbase);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path relative(const path& __p, error_code& __ec) {
-  return relative(__p, current_path(), __ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path relative(const path& __p, const path& __base=current_path()) {
-  return __weakly_canonical(__p).lexically_relative(__weakly_canonical(__base));
-}
-
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool remove(const path& __p) {
-    return __remove(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool remove(const path& __p, error_code& __ec) noexcept {
-    return __remove(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-uintmax_t remove_all(const path& __p) {
-    return __remove_all(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-uintmax_t remove_all(const path& __p, error_code& __ec) {
-    return __remove_all(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void rename(const path& __from, const path& __to) {
-    return __rename(__from, __to);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void rename(const path& __from, const path& __to, error_code& __ec) noexcept {
-    return __rename(__from, __to, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void resize_file(const path& __p, uintmax_t __ns) {
-    return __resize_file(__p, __ns);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-void resize_file(const path& __p, uintmax_t __ns, error_code& __ec) noexcept {
-    return __resize_file(__p, __ns, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-space_info space(const path& __p) {
-    return __space(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-space_info space(const path& __p, error_code& __ec) noexcept {
-    return __space(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-file_status status(const path& __p) {
-    return __status(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-file_status status(const path& __p, error_code& __ec) noexcept {
-    return __status(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-file_status symlink_status(const path& __p) {
-    return __symlink_status(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-file_status symlink_status(const path& __p, error_code& __ec) noexcept {
-    return __symlink_status(__p, &__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path temp_directory_path() {
-    return __temp_directory_path();
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path temp_directory_path(error_code& __ec) {
-    return __temp_directory_path(&__ec);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path weakly_canonical(path const& __p) {
-  return __weakly_canonical(__p);
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-path weakly_canonical(path const& __p, error_code& __ec) {
-  return __weakly_canonical(__p, &__ec);
-}
-
-
-class directory_iterator;
-class recursive_directory_iterator;
-class __dir_stream;
-
-class directory_entry
-{
-    typedef _VSTD_FS::path _Path;
-
-public:
-    // constructors and destructors
-    directory_entry() noexcept = default;
-    directory_entry(directory_entry const&) = default;
-    directory_entry(directory_entry&&) noexcept = default;
-
-    _LIBCPP_INLINE_VISIBILITY
-    explicit directory_entry(_Path const& __p) : __p_(__p) {
-      error_code __ec;
-      __refresh(&__ec);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    directory_entry(_Path const& __p, error_code &__ec) : __p_(__p) {
-      __refresh(&__ec);
-    }
-
-    ~directory_entry() {}
-
-    directory_entry& operator=(directory_entry const&) = default;
-    directory_entry& operator=(directory_entry&&) noexcept = default;
-
-    _LIBCPP_INLINE_VISIBILITY
-    void assign(_Path const& __p) {
-        __p_ = __p;
-        error_code __ec;
-        __refresh(&__ec);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    void assign(_Path const& __p, error_code& __ec) {
-        __p_ = __p;
-        __refresh(&__ec);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    void replace_filename(_Path const& __p) {
-      __p_.replace_filename(__p);
-      error_code __ec;
-      __refresh(&__ec);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    void replace_filename(_Path const& __p, error_code &__ec) {
-      __p_ = __p_.parent_path() / __p;
-      __refresh(&__ec);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    void refresh() {
-      __refresh();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    void refresh(error_code& __ec) noexcept { __refresh(&__ec); }
-
-    _LIBCPP_INLINE_VISIBILITY
-    _Path const& path() const noexcept {
-        return __p_;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    operator const _Path&() const noexcept {
-        return __p_;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool exists() const {
-      return _VSTD_FS::exists(file_status{__get_ft()});
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool exists(error_code& __ec) const noexcept {
-      return _VSTD_FS::exists(file_status{__get_ft(&__ec)});
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_block_file() const {
-      return __get_ft() == file_type::block;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_block_file(error_code& __ec) const noexcept {
-      return __get_ft(&__ec) == file_type::block;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_character_file() const {
-      return __get_ft() == file_type::character;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_character_file(error_code& __ec) const noexcept {
-      return __get_ft(&__ec) == file_type::character;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_directory() const {
-      return __get_ft() == file_type::directory;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_directory(error_code& __ec) const noexcept {
-      return __get_ft(&__ec) == file_type::directory;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_fifo() const {
-      return __get_ft() == file_type::fifo;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_fifo(error_code& __ec) const noexcept {
-      return __get_ft(&__ec) == file_type::fifo;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_other() const {
-      return _VSTD_FS::is_other(file_status{__get_ft()});
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_other(error_code& __ec) const noexcept {
-      return _VSTD_FS::is_other(file_status{__get_ft(&__ec)});
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_regular_file() const {
-      return __get_ft() == file_type::regular;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_regular_file(error_code& __ec) const noexcept {
-      return __get_ft(&__ec) == file_type::regular;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_socket() const {
-      return __get_ft() == file_type::socket;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_socket(error_code& __ec) const noexcept {
-      return __get_ft(&__ec) == file_type::socket;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_symlink() const {
-      return __get_sym_ft() == file_type::symlink;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool is_symlink(error_code& __ec) const noexcept {
-      return __get_sym_ft(&__ec) == file_type::symlink;
-    }
-    _LIBCPP_INLINE_VISIBILITY
-    uintmax_t file_size() const {
-      return __get_size();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    uintmax_t file_size(error_code& __ec) const noexcept {
-      return __get_size(&__ec);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    uintmax_t hard_link_count() const {
-      return __get_nlink();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    uintmax_t hard_link_count(error_code& __ec) const noexcept {
-      return __get_nlink(&__ec);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    file_time_type last_write_time() const {
-      return __get_write_time();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    file_time_type last_write_time(error_code& __ec) const noexcept {
-      return __get_write_time(&__ec);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    file_status status() const {
-        return __get_status();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    file_status status(error_code& __ec) const noexcept {
-        return __get_status(&__ec);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    file_status symlink_status() const {
-        return __get_symlink_status();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    file_status symlink_status(error_code& __ec) const noexcept {
-        return __get_symlink_status(&__ec);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator< (directory_entry const& __rhs) const noexcept {
-        return __p_ < __rhs.__p_;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator==(directory_entry const& __rhs) const noexcept {
-        return __p_ == __rhs.__p_;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator!=(directory_entry const& __rhs) const noexcept {
-        return __p_ != __rhs.__p_;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator<=(directory_entry const& __rhs) const noexcept {
-        return __p_ <= __rhs.__p_;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator> (directory_entry const& __rhs) const noexcept {
-        return __p_ > __rhs.__p_;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator>=(directory_entry const& __rhs) const noexcept {
-        return __p_ >= __rhs.__p_;
-    }
-
-private:
-    friend class directory_iterator;
-    friend class recursive_directory_iterator;
-    friend class __dir_stream;
-
-    enum _CacheType : unsigned char {
-      _Empty,
-      _IterSymlink,
-      _IterNonSymlink,
-      _RefreshSymlink,
-      _RefreshSymlinkUnresolved,
-      _RefreshNonSymlink
-    };
-
-    struct __cached_data {
-      uintmax_t __size_;
-      uintmax_t __nlink_;
-      file_time_type __write_time_;
-      perms __sym_perms_;
-      perms __non_sym_perms_;
-      file_type __type_;
-      _CacheType __cache_type_;
-
-      _LIBCPP_INLINE_VISIBILITY
-      __cached_data() noexcept { __reset(); }
-
-      _LIBCPP_INLINE_VISIBILITY
-      void __reset() {
-        __cache_type_ = _Empty;
-        __type_ = file_type::none;
-        __sym_perms_ = __non_sym_perms_ = perms::unknown;
-        __size_ = __nlink_ = uintmax_t(-1);
-        __write_time_ = file_time_type::min();
-      }
-    };
-
-    _LIBCPP_INLINE_VISIBILITY
-    static __cached_data __create_iter_result(file_type __ft) {
-      __cached_data __data;
-      __data.__type_ = __ft;
-      __data.__cache_type_ = [&]() {
-          switch (__ft) {
-          case file_type::none:
-            return _Empty;
-          case file_type::symlink:
-            return _IterSymlink;
-          default:
-            return _IterNonSymlink;
-          }
-      }();
-      return __data;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    void __assign_iter_entry(_Path&& __p, __cached_data __dt) {
-      __p_ = std::move(__p);
-      __data_ = __dt;
-    }
-
-    _LIBCPP_FUNC_VIS
-    error_code __do_refresh() noexcept;
-
-    _LIBCPP_INLINE_VISIBILITY
-    static bool __is_dne_error(error_code const& __ec) {
-      if (!__ec)
-        return true;
-      switch (static_cast<errc>(__ec.value())) {
-      case errc::no_such_file_or_directory:
-      case errc::not_a_directory:
-        return true;
-      default:
-        return false;
-      }
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    void __handle_error(const char* __msg, error_code* __dest_ec,
-                        error_code const& __ec,
-                        bool __allow_dne = false) const {
-      if (__dest_ec) {
-        *__dest_ec = __ec;
-        return;
-      }
-      if (__ec && (!__allow_dne || !__is_dne_error(__ec)))
-        __throw_filesystem_error(__msg, __p_, __ec);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    void __refresh(error_code* __ec = nullptr) {
-      __handle_error("in directory_entry::refresh", __ec, __do_refresh(),
-                     /*allow_dne*/ true);
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    file_type __get_sym_ft(error_code *__ec = nullptr) const {
-      switch (__data_.__cache_type_) {
-      case _Empty:
-        return __symlink_status(__p_, __ec).type();
-      case _IterSymlink:
-      case _RefreshSymlink:
-      case _RefreshSymlinkUnresolved:
-        if (__ec)
-          __ec->clear();
-        return file_type::symlink;
-      case _IterNonSymlink:
-      case _RefreshNonSymlink:
-        file_status __st(__data_.__type_);
-        if (__ec && !_VSTD_FS::exists(__st))
-          *__ec = make_error_code(errc::no_such_file_or_directory);
-        else if (__ec)
-          __ec->clear();
-        return __data_.__type_;
-      }
-      _LIBCPP_UNREACHABLE();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    file_type __get_ft(error_code *__ec = nullptr) const {
-      switch (__data_.__cache_type_) {
-      case _Empty:
-      case _IterSymlink:
-      case _RefreshSymlinkUnresolved:
-        return __status(__p_, __ec).type();
-      case _IterNonSymlink:
-      case _RefreshNonSymlink:
-      case _RefreshSymlink: {
-        file_status __st(__data_.__type_);
-        if (__ec && !_VSTD_FS::exists(__st))
-          *__ec = make_error_code(errc::no_such_file_or_directory);
-        else if (__ec)
-          __ec->clear();
-        return __data_.__type_;
-      }
-      }
-      _LIBCPP_UNREACHABLE();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    file_status __get_status(error_code *__ec = nullptr) const {
-      switch (__data_.__cache_type_) {
-      case _Empty:
-      case _IterNonSymlink:
-      case _IterSymlink:
-      case _RefreshSymlinkUnresolved:
-        return __status(__p_, __ec);
-      case _RefreshNonSymlink:
-      case _RefreshSymlink:
-        return file_status(__get_ft(__ec), __data_.__non_sym_perms_);
-      }
-      _LIBCPP_UNREACHABLE();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    file_status __get_symlink_status(error_code *__ec = nullptr) const {
-      switch (__data_.__cache_type_) {
-      case _Empty:
-      case _IterNonSymlink:
-      case _IterSymlink:
-        return __symlink_status(__p_, __ec);
-      case _RefreshNonSymlink:
-        return file_status(__get_sym_ft(__ec), __data_.__non_sym_perms_);
-      case _RefreshSymlink:
-      case _RefreshSymlinkUnresolved:
-        return file_status(__get_sym_ft(__ec), __data_.__sym_perms_);
-      }
-      _LIBCPP_UNREACHABLE();
-    }
-
-
-    _LIBCPP_INLINE_VISIBILITY
-    uintmax_t __get_size(error_code *__ec = nullptr) const {
-      switch (__data_.__cache_type_) {
-      case _Empty:
-      case _IterNonSymlink:
-      case _IterSymlink:
-      case _RefreshSymlinkUnresolved:
-        return _VSTD_FS::__file_size(__p_, __ec);
-      case _RefreshSymlink:
-      case _RefreshNonSymlink: {
-        error_code __m_ec;
-        file_status __st(__get_ft(&__m_ec));
-        __handle_error("in directory_entry::file_size", __ec, __m_ec);
-        if (_VSTD_FS::exists(__st) && !_VSTD_FS::is_regular_file(__st)) {
-          errc __err_kind = _VSTD_FS::is_directory(__st) ? errc::is_a_directory
-                                                         : errc::not_supported;
-          __handle_error("in directory_entry::file_size", __ec,
-                         make_error_code(__err_kind));
-        }
-        return __data_.__size_;
-      }
-      }
-      _LIBCPP_UNREACHABLE();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    uintmax_t __get_nlink(error_code *__ec = nullptr) const {
-      switch (__data_.__cache_type_) {
-      case _Empty:
-      case _IterNonSymlink:
-      case _IterSymlink:
-      case _RefreshSymlinkUnresolved:
-        return _VSTD_FS::__hard_link_count(__p_, __ec);
-      case _RefreshSymlink:
-      case _RefreshNonSymlink: {
-        error_code __m_ec;
-        (void)__get_ft(&__m_ec);
-        __handle_error("in directory_entry::hard_link_count", __ec, __m_ec);
-        return __data_.__nlink_;
-      }
-      }
-      _LIBCPP_UNREACHABLE();
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    file_time_type __get_write_time(error_code *__ec = nullptr) const {
-      switch (__data_.__cache_type_) {
-      case _Empty:
-      case _IterNonSymlink:
-      case _IterSymlink:
-      case _RefreshSymlinkUnresolved:
-        return _VSTD_FS::__last_write_time(__p_, __ec);
-      case _RefreshSymlink:
-      case _RefreshNonSymlink: {
-        error_code __m_ec;
-        file_status __st(__get_ft(&__m_ec));
-        __handle_error("in directory_entry::last_write_time", __ec, __m_ec);
-        if (_VSTD_FS::exists(__st) &&
-            __data_.__write_time_ == file_time_type::min())
-          __handle_error("in directory_entry::last_write_time", __ec,
-                         make_error_code(errc::value_too_large));
-        return __data_.__write_time_;
-      }
-      }
-      _LIBCPP_UNREACHABLE();
-    }
-private:
-    _Path __p_;
-    __cached_data __data_;
-};
-
-class __dir_element_proxy {
-public:
-
-    inline _LIBCPP_INLINE_VISIBILITY
-    directory_entry operator*() { return _VSTD::move(__elem_); }
-
-private:
-    friend class directory_iterator;
-    friend class recursive_directory_iterator;
-    explicit __dir_element_proxy(directory_entry const& __e) : __elem_(__e) {}
-    __dir_element_proxy(__dir_element_proxy&& __o) : __elem_(_VSTD::move(__o.__elem_)) {}
-    directory_entry __elem_;
-};
-
-class directory_iterator
-{
-public:
-    typedef directory_entry value_type;
-    typedef ptrdiff_t difference_type;
-    typedef value_type const* pointer;
-    typedef value_type const& reference;
-    typedef input_iterator_tag iterator_category;
-
-public:
-    //ctor & dtor
-    directory_iterator() noexcept
-    { }
-
-    explicit directory_iterator(const path& __p)
-        : directory_iterator(__p, nullptr)
-    { }
-
-    directory_iterator(const path& __p, directory_options __opts)
-        : directory_iterator(__p, nullptr, __opts)
-    { }
-
-    directory_iterator(const path& __p, error_code& __ec)
-        : directory_iterator(__p, &__ec)
-    { }
-
-    directory_iterator(const path& __p, directory_options __opts,
-                       error_code& __ec)
-        : directory_iterator(__p, &__ec, __opts)
-    { }
-
-    directory_iterator(const directory_iterator&) = default;
-    directory_iterator(directory_iterator&&) = default;
-    directory_iterator& operator=(const directory_iterator&) = default;
-
-    directory_iterator& operator=(directory_iterator&& __o) noexcept {
-        // non-default implementation provided to support self-move assign.
-        if (this != &__o) {
-            __imp_ = _VSTD::move(__o.__imp_);
-        }
-        return *this;
-    }
-
-    ~directory_iterator() = default;
-
-    const directory_entry& operator*() const {
-        _LIBCPP_ASSERT(__imp_, "The end iterator cannot be dereferenced");
-        return __dereference();
-    }
-
-    const directory_entry* operator->() const
-    { return &**this; }
-
-    directory_iterator& operator++()
-    { return __increment(); }
-
-    __dir_element_proxy operator++(int) {
-        __dir_element_proxy __p(**this);
-        __increment();
-        return __p;
-    }
-
-    directory_iterator& increment(error_code& __ec)
-    { return __increment(&__ec); }
-
-private:
-    inline _LIBCPP_INLINE_VISIBILITY
-    friend bool operator==(const directory_iterator& __lhs,
-                           const directory_iterator& __rhs) noexcept;
-
-    // construct the dir_stream
-    _LIBCPP_FUNC_VIS
-    directory_iterator(const path&, error_code *,
-                       directory_options = directory_options::none);
-
-    _LIBCPP_FUNC_VIS
-    directory_iterator& __increment(error_code * __ec = nullptr);
-
-    _LIBCPP_FUNC_VIS
-    const directory_entry& __dereference() const;
-
-private:
-    shared_ptr<__dir_stream> __imp_;
-};
-
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool operator==(const directory_iterator& __lhs,
-                const directory_iterator& __rhs) noexcept {
-    return __lhs.__imp_ == __rhs.__imp_;
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool operator!=(const directory_iterator& __lhs,
-                const directory_iterator& __rhs) noexcept {
-    return !(__lhs == __rhs);
-}
-
-// enable directory_iterator range-based for statements
-inline _LIBCPP_INLINE_VISIBILITY
-directory_iterator begin(directory_iterator __iter) noexcept {
-    return __iter;
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-directory_iterator end(const directory_iterator&) noexcept {
-    return directory_iterator();
-}
-
-class recursive_directory_iterator {
-public:
-    using value_type = directory_entry;
-    using difference_type = std::ptrdiff_t;
-    using pointer = directory_entry const *;
-    using reference = directory_entry const &;
-    using iterator_category = std::input_iterator_tag;
-
-public:
-    // constructors and destructor
-    _LIBCPP_INLINE_VISIBILITY
-    recursive_directory_iterator()  noexcept
-        : __rec_(false)
-    {}
-
-    _LIBCPP_INLINE_VISIBILITY
-    explicit recursive_directory_iterator(const path& __p,
-                directory_options __xoptions = directory_options::none)
-        : recursive_directory_iterator(__p, __xoptions,  nullptr)
-    { }
-
-    _LIBCPP_INLINE_VISIBILITY
-    recursive_directory_iterator(const path& __p,
-        directory_options __xoptions, error_code& __ec)
-        : recursive_directory_iterator(__p, __xoptions, &__ec)
-    { }
-
-    _LIBCPP_INLINE_VISIBILITY
-    recursive_directory_iterator(const path& __p, error_code& __ec)
-        : recursive_directory_iterator(__p, directory_options::none,  &__ec)
-    { }
-
-    recursive_directory_iterator(const recursive_directory_iterator&) = default;
-    recursive_directory_iterator(recursive_directory_iterator&&) = default;
-
-    recursive_directory_iterator &
-    operator=(const recursive_directory_iterator&) = default;
-
-    _LIBCPP_INLINE_VISIBILITY
-    recursive_directory_iterator &
-    operator=(recursive_directory_iterator&& __o) noexcept {
-        // non-default implementation provided to support self-move assign.
-        if (this != &__o) {
-            __imp_ = _VSTD::move(__o.__imp_);
-            __rec_ = __o.__rec_;
-        }
-        return *this;
-    }
-
-    ~recursive_directory_iterator() = default;
-
-    _LIBCPP_INLINE_VISIBILITY
-    const directory_entry& operator*() const
-    { return __dereference(); }
-
-    _LIBCPP_INLINE_VISIBILITY
-    const directory_entry* operator->() const
-    { return &__dereference(); }
-
-    recursive_directory_iterator& operator++()
-    { return __increment(); }
-
-    _LIBCPP_INLINE_VISIBILITY
-    __dir_element_proxy operator++(int) {
-        __dir_element_proxy __p(**this);
-        __increment();
-        return __p;
-    }
-
-    _LIBCPP_INLINE_VISIBILITY
-    recursive_directory_iterator& increment(error_code& __ec)
-    { return __increment(&__ec); }
-
-    _LIBCPP_FUNC_VIS directory_options options() const;
-    _LIBCPP_FUNC_VIS int  depth() const;
-
-    _LIBCPP_INLINE_VISIBILITY
-    void pop() { __pop(); }
-
-    _LIBCPP_INLINE_VISIBILITY
-    void pop(error_code& __ec)
-    { __pop(&__ec); }
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool recursion_pending() const
-    { return __rec_; }
-
-    _LIBCPP_INLINE_VISIBILITY
-    void disable_recursion_pending()
-    { __rec_ = false; }
-
-private:
-    recursive_directory_iterator(const path& __p, directory_options __opt,
-                                 error_code *__ec);
-
-    _LIBCPP_FUNC_VIS
-    const directory_entry& __dereference() const;
-
-    _LIBCPP_FUNC_VIS
-    bool __try_recursion(error_code* __ec);
-
-    _LIBCPP_FUNC_VIS
-    void __advance(error_code* __ec=nullptr);
-
-    _LIBCPP_FUNC_VIS
-    recursive_directory_iterator& __increment(error_code *__ec=nullptr);
-
-    _LIBCPP_FUNC_VIS
-    void __pop(error_code* __ec=nullptr);
-
-    inline _LIBCPP_INLINE_VISIBILITY
-    friend bool operator==(const recursive_directory_iterator&,
-                           const recursive_directory_iterator&) noexcept;
-
-    struct __shared_imp;
-    shared_ptr<__shared_imp> __imp_;
-    bool __rec_;
-};                                     // class recursive_directory_iterator
-
-
-inline _LIBCPP_INLINE_VISIBILITY
-bool operator==(const recursive_directory_iterator& __lhs,
-                const recursive_directory_iterator& __rhs) noexcept
-{
-    return __lhs.__imp_ == __rhs.__imp_;
-}
-
-_LIBCPP_INLINE_VISIBILITY
-inline bool operator!=(const recursive_directory_iterator& __lhs,
-                        const recursive_directory_iterator& __rhs) noexcept
-{
-    return !(__lhs == __rhs);
-}
-// enable recursive_directory_iterator range-based for statements
-inline _LIBCPP_INLINE_VISIBILITY
-recursive_directory_iterator begin(recursive_directory_iterator __iter) noexcept {
-    return __iter;
-}
-
-inline _LIBCPP_INLINE_VISIBILITY
-recursive_directory_iterator end(const recursive_directory_iterator&) noexcept {
-    return recursive_directory_iterator();
-}
+using namespace _VSTD_FS;
 
 _LIBCPP_END_NAMESPACE_EXPERIMENTAL_FILESYSTEM
 
diff --git a/include/filesystem b/include/filesystem
new file mode 100644
index 0000000..aa1d718
--- /dev/null
+++ b/include/filesystem
@@ -0,0 +1,2682 @@
+// -*- C++ -*-
+//===--------------------------- filesystem -------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+#ifndef _LIBCPP_FILESYSTEM
+#define _LIBCPP_FILESYSTEM
+/*
+    filesystem synopsis
+
+    namespace std { namespace filesystem {
+
+    class path;
+
+    void swap(path& lhs, path& rhs) noexcept;
+    size_t hash_value(const path& p) noexcept;
+
+    bool operator==(const path& lhs, const path& rhs) noexcept;
+    bool operator!=(const path& lhs, const path& rhs) noexcept;
+    bool operator< (const path& lhs, const path& rhs) noexcept;
+    bool operator<=(const path& lhs, const path& rhs) noexcept;
+    bool operator> (const path& lhs, const path& rhs) noexcept;
+    bool operator>=(const path& lhs, const path& rhs) noexcept;
+
+    path operator/ (const path& lhs, const path& rhs);
+
+    // fs.path.io operators are friends of path.
+    template <class charT, class traits>
+    friend basic_ostream<charT, traits>&
+    operator<<(basic_ostream<charT, traits>& os, const path& p);
+
+    template <class charT, class traits>
+    friend basic_istream<charT, traits>&
+    operator>>(basic_istream<charT, traits>& is, path& p);
+
+    template <class Source>
+      path u8path(const Source& source);
+    template <class InputIterator>
+      path u8path(InputIterator first, InputIterator last);
+
+    class filesystem_error;
+    class directory_entry;
+
+    class directory_iterator;
+
+    // enable directory_iterator range-based for statements
+    directory_iterator begin(directory_iterator iter) noexcept;
+    directory_iterator end(const directory_iterator&) noexcept;
+
+    class recursive_directory_iterator;
+
+    // enable recursive_directory_iterator range-based for statements
+    recursive_directory_iterator begin(recursive_directory_iterator iter) noexcept;
+    recursive_directory_iterator end(const recursive_directory_iterator&) noexcept;
+
+    class file_status;
+
+    struct space_info
+    {
+      uintmax_t capacity;
+      uintmax_t free;
+      uintmax_t available;
+    };
+
+    enum class file_type;
+    enum class perms;
+    enum class perm_options;
+    enum class copy_options;
+    enum class directory_options;
+
+    typedef chrono::time_point<trivial-clock>  file_time_type;
+
+    // operational functions
+
+    path absolute(const path& p);
+    path absolute(const path& p, error_code &ec);
+
+    path canonical(const path& p);
+    path canonical(const path& p, error_code& ec);
+
+    void copy(const path& from, const path& to);
+    void copy(const path& from, const path& to, error_code& ec);
+    void copy(const path& from, const path& to, copy_options options);
+    void copy(const path& from, const path& to, copy_options options,
+                   error_code& ec);
+
+    bool copy_file(const path& from, const path& to);
+    bool copy_file(const path& from, const path& to, error_code& ec);
+    bool copy_file(const path& from, const path& to, copy_options option);
+    bool copy_file(const path& from, const path& to, copy_options option,
+                           error_code& ec);
+
+    void copy_symlink(const path& existing_symlink, const path& new_symlink);
+    void copy_symlink(const path& existing_symlink, const path& new_symlink,
+                              error_code& ec) noexcept;
+
+    bool create_directories(const path& p);
+    bool create_directories(const path& p, error_code& ec);
+
+    bool create_directory(const path& p);
+    bool create_directory(const path& p, error_code& ec) noexcept;
+
+    bool create_directory(const path& p, const path& attributes);
+    bool create_directory(const path& p, const path& attributes,
+                                  error_code& ec) noexcept;
+
+    void create_directory_symlink(const path& to, const path& new_symlink);
+    void create_directory_symlink(const path& to, const path& new_symlink,
+                                          error_code& ec) noexcept;
+
+    void create_hard_link(const path& to, const path& new_hard_link);
+    void create_hard_link(const path& to, const path& new_hard_link,
+                                  error_code& ec) noexcept;
+
+    void create_symlink(const path& to, const path& new_symlink);
+    void create_symlink(const path& to, const path& new_symlink,
+                                error_code& ec) noexcept;
+
+    path current_path();
+    path current_path(error_code& ec);
+    void current_path(const path& p);
+    void current_path(const path& p, error_code& ec) noexcept;
+
+    bool exists(file_status s) noexcept;
+    bool exists(const path& p);
+    bool exists(const path& p, error_code& ec) noexcept;
+
+    bool equivalent(const path& p1, const path& p2);
+    bool equivalent(const path& p1, const path& p2, error_code& ec) noexcept;
+
+    uintmax_t    file_size(const path& p);
+    uintmax_t    file_size(const path& p, error_code& ec) noexcept;
+
+    uintmax_t    hard_link_count(const path& p);
+    uintmax_t    hard_link_count(const path& p, error_code& ec) noexcept;
+
+    bool is_block_file(file_status s) noexcept;
+    bool is_block_file(const path& p);
+    bool is_block_file(const path& p, error_code& ec) noexcept;
+
+    bool is_character_file(file_status s) noexcept;
+    bool is_character_file(const path& p);
+    bool is_character_file(const path& p, error_code& ec) noexcept;
+
+    bool is_directory(file_status s) noexcept;
+    bool is_directory(const path& p);
+    bool is_directory(const path& p, error_code& ec) noexcept;
+
+    bool is_empty(const path& p);
+    bool is_empty(const path& p, error_code& ec) noexcept;
+
+    bool is_fifo(file_status s) noexcept;
+    bool is_fifo(const path& p);
+    bool is_fifo(const path& p, error_code& ec) noexcept;
+
+    bool is_other(file_status s) noexcept;
+    bool is_other(const path& p);
+    bool is_other(const path& p, error_code& ec) noexcept;
+
+    bool is_regular_file(file_status s) noexcept;
+    bool is_regular_file(const path& p);
+    bool is_regular_file(const path& p, error_code& ec) noexcept;
+
+    bool is_socket(file_status s) noexcept;
+    bool is_socket(const path& p);
+    bool is_socket(const path& p, error_code& ec) noexcept;
+
+    bool is_symlink(file_status s) noexcept;
+    bool is_symlink(const path& p);
+    bool is_symlink(const path& p, error_code& ec) noexcept;
+
+    file_time_type  last_write_time(const path& p);
+    file_time_type  last_write_time(const path& p, error_code& ec) noexcept;
+    void last_write_time(const path& p, file_time_type new_time);
+    void last_write_time(const path& p, file_time_type new_time,
+                                 error_code& ec) noexcept;
+
+    void permissions(const path& p, perms prms,
+                     perm_options opts=perm_options::replace);
+    void permissions(const path& p, perms prms, error_code& ec) noexcept;
+    void permissions(const path& p, perms prms, perm_options opts,
+                     error_code& ec);
+
+    path proximate(const path& p, error_code& ec);
+    path proximate(const path& p, const path& base = current_path());
+    path proximate(const path& p, const path& base, error_code &ec);
+
+    path read_symlink(const path& p);
+    path read_symlink(const path& p, error_code& ec);
+
+    path relative(const path& p, error_code& ec);
+    path relative(const path& p, const path& base=current_path());
+    path relative(const path& p, const path& base, error_code& ec);
+
+    bool remove(const path& p);
+    bool remove(const path& p, error_code& ec) noexcept;
+
+    uintmax_t    remove_all(const path& p);
+    uintmax_t    remove_all(const path& p, error_code& ec);
+
+    void rename(const path& from, const path& to);
+    void rename(const path& from, const path& to, error_code& ec) noexcept;
+
+    void resize_file(const path& p, uintmax_t size);
+    void resize_file(const path& p, uintmax_t size, error_code& ec) noexcept;
+
+    space_info   space(const path& p);
+    space_info   space(const path& p, error_code& ec) noexcept;
+
+    file_status  status(const path& p);
+    file_status  status(const path& p, error_code& ec) noexcept;
+
+    bool status_known(file_status s) noexcept;
+
+    file_status  symlink_status(const path& p);
+    file_status  symlink_status(const path& p, error_code& ec) noexcept;
+
+    path temp_directory_path();
+    path temp_directory_path(error_code& ec);
+
+    path weakly_canonical(path const& p);
+    path weakly_canonical(path const& p, error_code& ec);
+
+
+} }  // namespaces std::filesystem
+
+*/
+
+#include <__config>
+#include <cstddef>
+#include <cstdlib>
+#include <chrono>
+#include <iterator>
+#include <iosfwd>
+#include <locale>
+#include <memory>
+#include <stack>
+#include <string>
+#include <system_error>
+#include <utility>
+#include <iomanip> // for quoted
+#include <string_view>
+
+#include <__debug>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#ifndef _LIBCPP_CXX03_LANG
+
+#if _LIBCPP_STD_VER >= 17
+#define __cpp_lib_filesystem 201703
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+struct _FilesystemClock {
+#if !defined(_LIBCPP_HAS_NO_INT128)
+  typedef __int128_t rep;
+  typedef nano period;
+#else
+  typedef long long rep;
+  typedef nano period;
+#endif
+
+  typedef chrono::duration<rep, period> duration;
+  typedef chrono::time_point<_FilesystemClock> time_point;
+
+  static _LIBCPP_CONSTEXPR_AFTER_CXX11 const bool is_steady = false;
+
+  _LIBCPP_FUNC_VIS static time_point now() noexcept;
+
+  _LIBCPP_INLINE_VISIBILITY
+  static time_t to_time_t(const time_point& __t) noexcept {
+    typedef chrono::duration<rep> __secs;
+    return time_t(
+        chrono::duration_cast<__secs>(__t.time_since_epoch()).count());
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  static time_point from_time_t(time_t __t) noexcept {
+    typedef chrono::duration<rep> __secs;
+    return time_point(__secs(__t));
+  }
+};
+
+typedef chrono::time_point<_FilesystemClock> file_time_type;
+
+struct _LIBCPP_TYPE_VIS space_info {
+  uintmax_t capacity;
+  uintmax_t free;
+  uintmax_t available;
+};
+
+enum class _LIBCPP_ENUM_VIS file_type : signed char {
+  none = 0,
+  not_found = -1,
+  regular = 1,
+  directory = 2,
+  symlink = 3,
+  block = 4,
+  character = 5,
+  fifo = 6,
+  socket = 7,
+  unknown = 8
+};
+
+enum class _LIBCPP_ENUM_VIS perms : unsigned {
+  none = 0,
+
+  owner_read = 0400,
+  owner_write = 0200,
+  owner_exec = 0100,
+  owner_all = 0700,
+
+  group_read = 040,
+  group_write = 020,
+  group_exec = 010,
+  group_all = 070,
+
+  others_read = 04,
+  others_write = 02,
+  others_exec = 01,
+  others_all = 07,
+
+  all = 0777,
+
+  set_uid = 04000,
+  set_gid = 02000,
+  sticky_bit = 01000,
+  mask = 07777,
+  unknown = 0xFFFF,
+};
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr perms operator&(perms _LHS, perms _RHS) {
+  return static_cast<perms>(static_cast<unsigned>(_LHS) &
+                            static_cast<unsigned>(_RHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr perms operator|(perms _LHS, perms _RHS) {
+  return static_cast<perms>(static_cast<unsigned>(_LHS) |
+                            static_cast<unsigned>(_RHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr perms operator^(perms _LHS, perms _RHS) {
+  return static_cast<perms>(static_cast<unsigned>(_LHS) ^
+                            static_cast<unsigned>(_RHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr perms operator~(perms _LHS) {
+  return static_cast<perms>(~static_cast<unsigned>(_LHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline perms& operator&=(perms& _LHS, perms _RHS) { return _LHS = _LHS & _RHS; }
+
+_LIBCPP_INLINE_VISIBILITY
+inline perms& operator|=(perms& _LHS, perms _RHS) { return _LHS = _LHS | _RHS; }
+
+_LIBCPP_INLINE_VISIBILITY
+inline perms& operator^=(perms& _LHS, perms _RHS) { return _LHS = _LHS ^ _RHS; }
+
+enum class _LIBCPP_ENUM_VIS perm_options : unsigned char {
+  replace = 1,
+  add = 2,
+  remove = 4,
+  nofollow = 8
+};
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr perm_options operator&(perm_options _LHS, perm_options _RHS) {
+  return static_cast<perm_options>(static_cast<unsigned>(_LHS) &
+                                   static_cast<unsigned>(_RHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr perm_options operator|(perm_options _LHS, perm_options _RHS) {
+  return static_cast<perm_options>(static_cast<unsigned>(_LHS) |
+                                   static_cast<unsigned>(_RHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr perm_options operator^(perm_options _LHS, perm_options _RHS) {
+  return static_cast<perm_options>(static_cast<unsigned>(_LHS) ^
+                                   static_cast<unsigned>(_RHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr perm_options operator~(perm_options _LHS) {
+  return static_cast<perm_options>(~static_cast<unsigned>(_LHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline perm_options& operator&=(perm_options& _LHS, perm_options _RHS) {
+  return _LHS = _LHS & _RHS;
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline perm_options& operator|=(perm_options& _LHS, perm_options _RHS) {
+  return _LHS = _LHS | _RHS;
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline perm_options& operator^=(perm_options& _LHS, perm_options _RHS) {
+  return _LHS = _LHS ^ _RHS;
+}
+
+enum class _LIBCPP_ENUM_VIS copy_options : unsigned short {
+  none = 0,
+  skip_existing = 1,
+  overwrite_existing = 2,
+  update_existing = 4,
+  recursive = 8,
+  copy_symlinks = 16,
+  skip_symlinks = 32,
+  directories_only = 64,
+  create_symlinks = 128,
+  create_hard_links = 256,
+  __in_recursive_copy = 512,
+};
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr copy_options operator&(copy_options _LHS, copy_options _RHS) {
+  return static_cast<copy_options>(static_cast<unsigned short>(_LHS) &
+                                   static_cast<unsigned short>(_RHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr copy_options operator|(copy_options _LHS, copy_options _RHS) {
+  return static_cast<copy_options>(static_cast<unsigned short>(_LHS) |
+                                   static_cast<unsigned short>(_RHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr copy_options operator^(copy_options _LHS, copy_options _RHS) {
+  return static_cast<copy_options>(static_cast<unsigned short>(_LHS) ^
+                                   static_cast<unsigned short>(_RHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr copy_options operator~(copy_options _LHS) {
+  return static_cast<copy_options>(~static_cast<unsigned short>(_LHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline copy_options& operator&=(copy_options& _LHS, copy_options _RHS) {
+  return _LHS = _LHS & _RHS;
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline copy_options& operator|=(copy_options& _LHS, copy_options _RHS) {
+  return _LHS = _LHS | _RHS;
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline copy_options& operator^=(copy_options& _LHS, copy_options _RHS) {
+  return _LHS = _LHS ^ _RHS;
+}
+
+enum class _LIBCPP_ENUM_VIS directory_options : unsigned char {
+  none = 0,
+  follow_directory_symlink = 1,
+  skip_permission_denied = 2
+};
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr directory_options operator&(directory_options _LHS,
+                                             directory_options _RHS) {
+  return static_cast<directory_options>(static_cast<unsigned char>(_LHS) &
+                                        static_cast<unsigned char>(_RHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr directory_options operator|(directory_options _LHS,
+                                             directory_options _RHS) {
+  return static_cast<directory_options>(static_cast<unsigned char>(_LHS) |
+                                        static_cast<unsigned char>(_RHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr directory_options operator^(directory_options _LHS,
+                                             directory_options _RHS) {
+  return static_cast<directory_options>(static_cast<unsigned char>(_LHS) ^
+                                        static_cast<unsigned char>(_RHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline constexpr directory_options operator~(directory_options _LHS) {
+  return static_cast<directory_options>(~static_cast<unsigned char>(_LHS));
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline directory_options& operator&=(directory_options& _LHS,
+                                     directory_options _RHS) {
+  return _LHS = _LHS & _RHS;
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline directory_options& operator|=(directory_options& _LHS,
+                                     directory_options _RHS) {
+  return _LHS = _LHS | _RHS;
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline directory_options& operator^=(directory_options& _LHS,
+                                     directory_options _RHS) {
+  return _LHS = _LHS ^ _RHS;
+}
+
+class _LIBCPP_TYPE_VIS file_status {
+public:
+  // constructors
+  _LIBCPP_INLINE_VISIBILITY
+  file_status() noexcept : file_status(file_type::none) {}
+  _LIBCPP_INLINE_VISIBILITY
+  explicit file_status(file_type __ft, perms __prms = perms::unknown) noexcept
+      : __ft_(__ft),
+        __prms_(__prms) {}
+
+  file_status(const file_status&) noexcept = default;
+  file_status(file_status&&) noexcept = default;
+
+  _LIBCPP_INLINE_VISIBILITY
+  ~file_status() {}
+
+  file_status& operator=(const file_status&) noexcept = default;
+  file_status& operator=(file_status&&) noexcept = default;
+
+  // observers
+  _LIBCPP_INLINE_VISIBILITY
+  file_type type() const noexcept { return __ft_; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  perms permissions() const noexcept { return __prms_; }
+
+  // modifiers
+  _LIBCPP_INLINE_VISIBILITY
+  void type(file_type __ft) noexcept { __ft_ = __ft; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  void permissions(perms __p) noexcept { __prms_ = __p; }
+
+private:
+  file_type __ft_;
+  perms __prms_;
+};
+
+class _LIBCPP_TYPE_VIS directory_entry;
+
+template <class _Tp>
+struct __can_convert_char {
+  static const bool value = false;
+};
+template <class _Tp>
+struct __can_convert_char<const _Tp> : public __can_convert_char<_Tp> {};
+template <>
+struct __can_convert_char<char> {
+  static const bool value = true;
+  using __char_type = char;
+};
+template <>
+struct __can_convert_char<wchar_t> {
+  static const bool value = true;
+  using __char_type = wchar_t;
+};
+template <>
+struct __can_convert_char<char16_t> {
+  static const bool value = true;
+  using __char_type = char16_t;
+};
+template <>
+struct __can_convert_char<char32_t> {
+  static const bool value = true;
+  using __char_type = char32_t;
+};
+
+template <class _ECharT>
+typename enable_if<__can_convert_char<_ECharT>::value, bool>::type
+__is_separator(_ECharT __e) {
+  return __e == _ECharT('/');
+};
+
+struct _NullSentinal {};
+
+template <class _Tp>
+using _Void = void;
+
+template <class _Tp, class = void>
+struct __is_pathable_string : public false_type {};
+
+template <class _ECharT, class _Traits, class _Alloc>
+struct __is_pathable_string<
+    basic_string<_ECharT, _Traits, _Alloc>,
+    _Void<typename __can_convert_char<_ECharT>::__char_type> >
+    : public __can_convert_char<_ECharT> {
+  using _Str = basic_string<_ECharT, _Traits, _Alloc>;
+  using _Base = __can_convert_char<_ECharT>;
+  static _ECharT const* __range_begin(_Str const& __s) { return __s.data(); }
+  static _ECharT const* __range_end(_Str const& __s) {
+    return __s.data() + __s.length();
+  }
+  static _ECharT __first_or_null(_Str const& __s) {
+    return __s.empty() ? _ECharT{} : __s[0];
+  }
+};
+
+template <class _ECharT, class _Traits>
+struct __is_pathable_string<
+    basic_string_view<_ECharT, _Traits>,
+    _Void<typename __can_convert_char<_ECharT>::__char_type> >
+    : public __can_convert_char<_ECharT> {
+  using _Str = basic_string_view<_ECharT, _Traits>;
+  using _Base = __can_convert_char<_ECharT>;
+  static _ECharT const* __range_begin(_Str const& __s) { return __s.data(); }
+  static _ECharT const* __range_end(_Str const& __s) {
+    return __s.data() + __s.length();
+  }
+  static _ECharT __first_or_null(_Str const& __s) {
+    return __s.empty() ? _ECharT{} : __s[0];
+  }
+};
+
+template <class _Source, class _DS = typename decay<_Source>::type,
+          class _UnqualPtrType =
+              typename remove_const<typename remove_pointer<_DS>::type>::type,
+          bool _IsCharPtr = is_pointer<_DS>::value&&
+              __can_convert_char<_UnqualPtrType>::value>
+struct __is_pathable_char_array : false_type {};
+
+template <class _Source, class _ECharT, class _UPtr>
+struct __is_pathable_char_array<_Source, _ECharT*, _UPtr, true>
+    : __can_convert_char<typename remove_const<_ECharT>::type> {
+  using _Base = __can_convert_char<typename remove_const<_ECharT>::type>;
+
+  static _ECharT const* __range_begin(const _ECharT* __b) { return __b; }
+  static _ECharT const* __range_end(const _ECharT* __b) {
+    using _Iter = const _ECharT*;
+    const _ECharT __sentinal = _ECharT{};
+    _Iter __e = __b;
+    for (; *__e != __sentinal; ++__e)
+      ;
+    return __e;
+  }
+
+  static _ECharT __first_or_null(const _ECharT* __b) { return *__b; }
+};
+
+template <class _Iter, bool _IsIt = __is_input_iterator<_Iter>::value,
+          class = void>
+struct __is_pathable_iter : false_type {};
+
+template <class _Iter>
+struct __is_pathable_iter<
+    _Iter, true,
+    _Void<typename __can_convert_char<
+        typename iterator_traits<_Iter>::value_type>::__char_type> >
+    : __can_convert_char<typename iterator_traits<_Iter>::value_type> {
+  using _ECharT = typename iterator_traits<_Iter>::value_type;
+  using _Base = __can_convert_char<_ECharT>;
+
+  static _Iter __range_begin(_Iter __b) { return __b; }
+  static _NullSentinal __range_end(_Iter) { return _NullSentinal{}; }
+
+  static _ECharT __first_or_null(_Iter __b) { return *__b; }
+};
+
+template <class _Tp, bool _IsStringT = __is_pathable_string<_Tp>::value,
+          bool _IsCharIterT = __is_pathable_char_array<_Tp>::value,
+          bool _IsIterT = !_IsCharIterT && __is_pathable_iter<_Tp>::value>
+struct __is_pathable : false_type {
+  static_assert(!_IsStringT && !_IsCharIterT && !_IsIterT, "Must all be false");
+};
+
+template <class _Tp>
+struct __is_pathable<_Tp, true, false, false> : __is_pathable_string<_Tp> {};
+
+template <class _Tp>
+struct __is_pathable<_Tp, false, true, false> : __is_pathable_char_array<_Tp> {
+};
+
+template <class _Tp>
+struct __is_pathable<_Tp, false, false, true> : __is_pathable_iter<_Tp> {};
+
+template <class _ECharT>
+struct _PathCVT {
+  static_assert(__can_convert_char<_ECharT>::value,
+                "Char type not convertible");
+
+  typedef __narrow_to_utf8<sizeof(_ECharT) * __CHAR_BIT__> _Narrower;
+
+  static void __append_range(string& __dest, _ECharT const* __b,
+                             _ECharT const* __e) {
+    _Narrower()(back_inserter(__dest), __b, __e);
+  }
+
+  template <class _Iter>
+  static void __append_range(string& __dest, _Iter __b, _Iter __e) {
+    static_assert(!is_same<_Iter, _ECharT*>::value, "Call const overload");
+    if (__b == __e)
+      return;
+    basic_string<_ECharT> __tmp(__b, __e);
+    _Narrower()(back_inserter(__dest), __tmp.data(),
+                __tmp.data() + __tmp.length());
+  }
+
+  template <class _Iter>
+  static void __append_range(string& __dest, _Iter __b, _NullSentinal) {
+    static_assert(!is_same<_Iter, _ECharT*>::value, "Call const overload");
+    const _ECharT __sentinal = _ECharT{};
+    if (*__b == __sentinal)
+      return;
+    basic_string<_ECharT> __tmp;
+    for (; *__b != __sentinal; ++__b)
+      __tmp.push_back(*__b);
+    _Narrower()(back_inserter(__dest), __tmp.data(),
+                __tmp.data() + __tmp.length());
+  }
+
+  template <class _Source>
+  static void __append_source(string& __dest, _Source const& __s) {
+    using _Traits = __is_pathable<_Source>;
+    __append_range(__dest, _Traits::__range_begin(__s),
+                   _Traits::__range_end(__s));
+  }
+};
+
+template <>
+struct _PathCVT<char> {
+
+  template <class _Iter>
+  static typename enable_if<__is_exactly_input_iterator<_Iter>::value>::type
+  __append_range(string& __dest, _Iter __b, _Iter __e) {
+    for (; __b != __e; ++__b)
+      __dest.push_back(*__b);
+  }
+
+  template <class _Iter>
+  static typename enable_if<__is_forward_iterator<_Iter>::value>::type
+  __append_range(string& __dest, _Iter __b, _Iter __e) {
+    __dest.__append_forward_unsafe(__b, __e);
+  }
+
+  template <class _Iter>
+  static void __append_range(string& __dest, _Iter __b, _NullSentinal) {
+    const char __sentinal = char{};
+    for (; *__b != __sentinal; ++__b)
+      __dest.push_back(*__b);
+  }
+
+  template <class _Source>
+  static void __append_source(string& __dest, _Source const& __s) {
+    using _Traits = __is_pathable<_Source>;
+    __append_range(__dest, _Traits::__range_begin(__s),
+                   _Traits::__range_end(__s));
+  }
+};
+
+class _LIBCPP_TYPE_VIS path {
+  template <class _SourceOrIter, class _Tp = path&>
+  using _EnableIfPathable =
+      typename enable_if<__is_pathable<_SourceOrIter>::value, _Tp>::type;
+
+  template <class _Tp>
+  using _SourceChar = typename __is_pathable<_Tp>::__char_type;
+
+  template <class _Tp>
+  using _SourceCVT = _PathCVT<_SourceChar<_Tp> >;
+
+public:
+  typedef char value_type;
+  typedef basic_string<value_type> string_type;
+  typedef _VSTD::string_view __string_view;
+  static constexpr value_type preferred_separator = '/';
+
+  enum class _LIBCPP_ENUM_VIS format : unsigned char {
+    auto_format,
+    native_format,
+    generic_format
+  };
+
+  // constructors and destructor
+  _LIBCPP_INLINE_VISIBILITY path() noexcept {}
+  _LIBCPP_INLINE_VISIBILITY path(const path& __p) : __pn_(__p.__pn_) {}
+  _LIBCPP_INLINE_VISIBILITY path(path&& __p) noexcept
+      : __pn_(_VSTD::move(__p.__pn_)) {}
+
+  _LIBCPP_INLINE_VISIBILITY
+  path(string_type&& __s, format = format::auto_format) noexcept
+      : __pn_(_VSTD::move(__s)) {}
+
+  template <class _Source, class = _EnableIfPathable<_Source, void> >
+  path(const _Source& __src, format = format::auto_format) {
+    _SourceCVT<_Source>::__append_source(__pn_, __src);
+  }
+
+  template <class _InputIt>
+  path(_InputIt __first, _InputIt __last, format = format::auto_format) {
+    typedef typename iterator_traits<_InputIt>::value_type _ItVal;
+    _PathCVT<_ItVal>::__append_range(__pn_, __first, __last);
+  }
+
+  // TODO Implement locale conversions.
+  template <class _Source, class = _EnableIfPathable<_Source, void> >
+  path(const _Source& __src, const locale& __loc, format = format::auto_format);
+  template <class _InputIt>
+  path(_InputIt __first, _InputIt _last, const locale& __loc,
+       format = format::auto_format);
+
+  _LIBCPP_INLINE_VISIBILITY
+  ~path() = default;
+
+  // assignments
+  _LIBCPP_INLINE_VISIBILITY
+  path& operator=(const path& __p) {
+    __pn_ = __p.__pn_;
+    return *this;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  path& operator=(path&& __p) noexcept {
+    __pn_ = _VSTD::move(__p.__pn_);
+    return *this;
+  }
+
+  template <class = void>
+  _LIBCPP_INLINE_VISIBILITY path& operator=(string_type&& __s) noexcept {
+    __pn_ = _VSTD::move(__s);
+    return *this;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  path& assign(string_type&& __s) noexcept {
+    __pn_ = _VSTD::move(__s);
+    return *this;
+  }
+
+  template <class _Source>
+  _LIBCPP_INLINE_VISIBILITY _EnableIfPathable<_Source>
+  operator=(const _Source& __src) {
+    return this->assign(__src);
+  }
+
+  template <class _Source>
+  _EnableIfPathable<_Source> assign(const _Source& __src) {
+    __pn_.clear();
+    _SourceCVT<_Source>::__append_source(__pn_, __src);
+    return *this;
+  }
+
+  template <class _InputIt>
+  path& assign(_InputIt __first, _InputIt __last) {
+    typedef typename iterator_traits<_InputIt>::value_type _ItVal;
+    __pn_.clear();
+    _PathCVT<_ItVal>::__append_range(__pn_, __first, __last);
+    return *this;
+  }
+
+private:
+  template <class _ECharT>
+  static bool __source_is_absolute(_ECharT __first_or_null) {
+    return __is_separator(__first_or_null);
+  }
+
+public:
+  // appends
+  path& operator/=(const path& __p) {
+    if (__p.is_absolute()) {
+      __pn_ = __p.__pn_;
+      return *this;
+    }
+    if (has_filename())
+      __pn_ += preferred_separator;
+    __pn_ += __p.native();
+    return *this;
+  }
+
+  // FIXME: Use _LIBCPP_DIAGNOSE_WARNING to produce a diagnostic when __src
+  // is known at compile time to be "/' since the user almost certainly intended
+  // to append a separator instead of overwriting the path with "/"
+  template <class _Source>
+  _LIBCPP_INLINE_VISIBILITY _EnableIfPathable<_Source>
+  operator/=(const _Source& __src) {
+    return this->append(__src);
+  }
+
+  template <class _Source>
+  _EnableIfPathable<_Source> append(const _Source& __src) {
+    using _Traits = __is_pathable<_Source>;
+    using _CVT = _PathCVT<_SourceChar<_Source> >;
+    if (__source_is_absolute(_Traits::__first_or_null(__src)))
+      __pn_.clear();
+    else if (has_filename())
+      __pn_ += preferred_separator;
+    _CVT::__append_source(__pn_, __src);
+    return *this;
+  }
+
+  template <class _InputIt>
+  path& append(_InputIt __first, _InputIt __last) {
+    typedef typename iterator_traits<_InputIt>::value_type _ItVal;
+    static_assert(__can_convert_char<_ItVal>::value, "Must convertible");
+    using _CVT = _PathCVT<_ItVal>;
+    if (__first != __last && __source_is_absolute(*__first))
+      __pn_.clear();
+    else if (has_filename())
+      __pn_ += preferred_separator;
+    _CVT::__append_range(__pn_, __first, __last);
+    return *this;
+  }
+
+  // concatenation
+  _LIBCPP_INLINE_VISIBILITY
+  path& operator+=(const path& __x) {
+    __pn_ += __x.__pn_;
+    return *this;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  path& operator+=(const string_type& __x) {
+    __pn_ += __x;
+    return *this;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  path& operator+=(__string_view __x) {
+    __pn_ += __x;
+    return *this;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  path& operator+=(const value_type* __x) {
+    __pn_ += __x;
+    return *this;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  path& operator+=(value_type __x) {
+    __pn_ += __x;
+    return *this;
+  }
+
+  template <class _ECharT>
+  typename enable_if<__can_convert_char<_ECharT>::value, path&>::type
+  operator+=(_ECharT __x) {
+    basic_string<_ECharT> __tmp;
+    __tmp += __x;
+    _PathCVT<_ECharT>::__append_source(__pn_, __tmp);
+    return *this;
+  }
+
+  template <class _Source>
+  _EnableIfPathable<_Source> operator+=(const _Source& __x) {
+    return this->concat(__x);
+  }
+
+  template <class _Source>
+  _EnableIfPathable<_Source> concat(const _Source& __x) {
+    _SourceCVT<_Source>::__append_source(__pn_, __x);
+    return *this;
+  }
+
+  template <class _InputIt>
+  path& concat(_InputIt __first, _InputIt __last) {
+    typedef typename iterator_traits<_InputIt>::value_type _ItVal;
+    _PathCVT<_ItVal>::__append_range(__pn_, __first, __last);
+    return *this;
+  }
+
+  // modifiers
+  _LIBCPP_INLINE_VISIBILITY
+  void clear() noexcept { __pn_.clear(); }
+
+  path& make_preferred() { return *this; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  path& remove_filename() {
+    auto __fname = __filename();
+    if (!__fname.empty())
+      __pn_.erase(__fname.data() - __pn_.data());
+    return *this;
+  }
+
+  path& replace_filename(const path& __replacement) {
+    remove_filename();
+    return (*this /= __replacement);
+  }
+
+  path& replace_extension(const path& __replacement = path());
+
+  _LIBCPP_INLINE_VISIBILITY
+  void swap(path& __rhs) noexcept { __pn_.swap(__rhs.__pn_); }
+
+  // private helper to allow reserving memory in the path
+  _LIBCPP_INLINE_VISIBILITY
+  void __reserve(size_t __s) { __pn_.reserve(__s); }
+
+  // native format observers
+  _LIBCPP_INLINE_VISIBILITY
+  const string_type& native() const noexcept { return __pn_; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  const value_type* c_str() const noexcept { return __pn_.c_str(); }
+
+  _LIBCPP_INLINE_VISIBILITY operator string_type() const { return __pn_; }
+
+  template <class _ECharT, class _Traits = char_traits<_ECharT>,
+            class _Allocator = allocator<_ECharT> >
+  basic_string<_ECharT, _Traits, _Allocator>
+  string(const _Allocator& __a = _Allocator()) const {
+    using _CVT = __widen_from_utf8<sizeof(_ECharT) * __CHAR_BIT__>;
+    using _Str = basic_string<_ECharT, _Traits, _Allocator>;
+    _Str __s(__a);
+    __s.reserve(__pn_.size());
+    _CVT()(back_inserter(__s), __pn_.data(), __pn_.data() + __pn_.size());
+    return __s;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY std::string string() const { return __pn_; }
+  _LIBCPP_INLINE_VISIBILITY std::wstring wstring() const {
+    return string<wchar_t>();
+  }
+  _LIBCPP_INLINE_VISIBILITY std::string u8string() const { return __pn_; }
+  _LIBCPP_INLINE_VISIBILITY std::u16string u16string() const {
+    return string<char16_t>();
+  }
+  _LIBCPP_INLINE_VISIBILITY std::u32string u32string() const {
+    return string<char32_t>();
+  }
+
+  // generic format observers
+  template <class _ECharT, class _Traits = char_traits<_ECharT>,
+            class _Allocator = allocator<_ECharT> >
+  basic_string<_ECharT, _Traits, _Allocator>
+  generic_string(const _Allocator& __a = _Allocator()) const {
+    return string<_ECharT, _Traits, _Allocator>(__a);
+  }
+
+  std::string generic_string() const { return __pn_; }
+  std::wstring generic_wstring() const { return string<wchar_t>(); }
+  std::string generic_u8string() const { return __pn_; }
+  std::u16string generic_u16string() const { return string<char16_t>(); }
+  std::u32string generic_u32string() const { return string<char32_t>(); }
+
+private:
+  int __compare(__string_view) const;
+  __string_view __root_name() const;
+  __string_view __root_directory() const;
+  __string_view __root_path_raw() const;
+  __string_view __relative_path() const;
+  __string_view __parent_path() const;
+  __string_view __filename() const;
+  __string_view __stem() const;
+  __string_view __extension() const;
+
+public:
+  // compare
+  _LIBCPP_INLINE_VISIBILITY int compare(const path& __p) const noexcept {
+    return __compare(__p.__pn_);
+  }
+  _LIBCPP_INLINE_VISIBILITY int compare(const string_type& __s) const {
+    return __compare(__s);
+  }
+  _LIBCPP_INLINE_VISIBILITY int compare(__string_view __s) const {
+    return __compare(__s);
+  }
+  _LIBCPP_INLINE_VISIBILITY int compare(const value_type* __s) const {
+    return __compare(__s);
+  }
+
+  // decomposition
+  _LIBCPP_INLINE_VISIBILITY path root_name() const {
+    return string_type(__root_name());
+  }
+  _LIBCPP_INLINE_VISIBILITY path root_directory() const {
+    return string_type(__root_directory());
+  }
+  _LIBCPP_INLINE_VISIBILITY path root_path() const {
+    return root_name().append(string_type(__root_directory()));
+  }
+  _LIBCPP_INLINE_VISIBILITY path relative_path() const {
+    return string_type(__relative_path());
+  }
+  _LIBCPP_INLINE_VISIBILITY path parent_path() const {
+    return string_type(__parent_path());
+  }
+  _LIBCPP_INLINE_VISIBILITY path filename() const {
+    return string_type(__filename());
+  }
+  _LIBCPP_INLINE_VISIBILITY path stem() const { return string_type(__stem()); }
+  _LIBCPP_INLINE_VISIBILITY path extension() const {
+    return string_type(__extension());
+  }
+
+  // query
+  _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY bool
+  empty() const noexcept {
+    return __pn_.empty();
+  }
+
+  _LIBCPP_INLINE_VISIBILITY bool has_root_name() const {
+    return !__root_name().empty();
+  }
+  _LIBCPP_INLINE_VISIBILITY bool has_root_directory() const {
+    return !__root_directory().empty();
+  }
+  _LIBCPP_INLINE_VISIBILITY bool has_root_path() const {
+    return !__root_path_raw().empty();
+  }
+  _LIBCPP_INLINE_VISIBILITY bool has_relative_path() const {
+    return !__relative_path().empty();
+  }
+  _LIBCPP_INLINE_VISIBILITY bool has_parent_path() const {
+    return !__parent_path().empty();
+  }
+  _LIBCPP_INLINE_VISIBILITY bool has_filename() const {
+    return !__filename().empty();
+  }
+  _LIBCPP_INLINE_VISIBILITY bool has_stem() const { return !__stem().empty(); }
+  _LIBCPP_INLINE_VISIBILITY bool has_extension() const {
+    return !__extension().empty();
+  }
+
+  _LIBCPP_INLINE_VISIBILITY bool is_absolute() const {
+    return has_root_directory();
+  }
+  _LIBCPP_INLINE_VISIBILITY bool is_relative() const { return !is_absolute(); }
+
+  // relative paths
+  path lexically_normal() const;
+  path lexically_relative(const path& __base) const;
+
+  _LIBCPP_INLINE_VISIBILITY path lexically_proximate(const path& __base) const {
+    path __result = this->lexically_relative(__base);
+    if (__result.native().empty())
+      return *this;
+    return __result;
+  }
+
+  // iterators
+  class _LIBCPP_TYPE_VIS iterator;
+  typedef iterator const_iterator;
+
+  iterator begin() const;
+  iterator end() const;
+
+  template <class _CharT, class _Traits>
+  _LIBCPP_INLINE_VISIBILITY friend
+      typename enable_if<is_same<_CharT, char>::value &&
+                             is_same<_Traits, char_traits<char> >::value,
+                         basic_ostream<_CharT, _Traits>&>::type
+      operator<<(basic_ostream<_CharT, _Traits>& __os, const path& __p) {
+    __os << std::__quoted(__p.native());
+    return __os;
+  }
+
+  template <class _CharT, class _Traits>
+  _LIBCPP_INLINE_VISIBILITY friend
+      typename enable_if<!is_same<_CharT, char>::value ||
+                             !is_same<_Traits, char_traits<char> >::value,
+                         basic_ostream<_CharT, _Traits>&>::type
+      operator<<(basic_ostream<_CharT, _Traits>& __os, const path& __p) {
+    __os << std::__quoted(__p.string<_CharT, _Traits>());
+    return __os;
+  }
+
+  template <class _CharT, class _Traits>
+  _LIBCPP_INLINE_VISIBILITY friend basic_istream<_CharT, _Traits>&
+  operator>>(basic_istream<_CharT, _Traits>& __is, path& __p) {
+    basic_string<_CharT, _Traits> __tmp;
+    __is >> __quoted(__tmp);
+    __p = __tmp;
+    return __is;
+  }
+
+private:
+  inline _LIBCPP_INLINE_VISIBILITY path&
+  __assign_view(__string_view const& __s) noexcept {
+    __pn_ = string_type(__s);
+    return *this;
+  }
+  string_type __pn_;
+};
+
+inline _LIBCPP_INLINE_VISIBILITY void swap(path& __lhs, path& __rhs) noexcept {
+  __lhs.swap(__rhs);
+}
+
+_LIBCPP_FUNC_VIS
+size_t hash_value(const path& __p) noexcept;
+
+inline _LIBCPP_INLINE_VISIBILITY bool operator==(const path& __lhs,
+                                                 const path& __rhs) noexcept {
+  return __lhs.compare(__rhs) == 0;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool operator!=(const path& __lhs,
+                                                 const path& __rhs) noexcept {
+  return __lhs.compare(__rhs) != 0;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool operator<(const path& __lhs,
+                                                const path& __rhs) noexcept {
+  return __lhs.compare(__rhs) < 0;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool operator<=(const path& __lhs,
+                                                 const path& __rhs) noexcept {
+  return __lhs.compare(__rhs) <= 0;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool operator>(const path& __lhs,
+                                                const path& __rhs) noexcept {
+  return __lhs.compare(__rhs) > 0;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool operator>=(const path& __lhs,
+                                                 const path& __rhs) noexcept {
+  return __lhs.compare(__rhs) >= 0;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path operator/(const path& __lhs,
+                                                const path& __rhs) {
+  path __result(__lhs);
+  __result /= __rhs;
+  return __result;
+}
+
+template <class _Source>
+_LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_pathable<_Source>::value, path>::type
+    u8path(const _Source& __s) {
+  static_assert(
+      is_same<typename __is_pathable<_Source>::__char_type, char>::value,
+      "u8path(Source const&) requires Source have a character type of type "
+      "'char'");
+  return path(__s);
+}
+
+template <class _InputIt>
+_LIBCPP_INLINE_VISIBILITY
+    typename enable_if<__is_pathable<_InputIt>::value, path>::type
+    u8path(_InputIt __f, _InputIt __l) {
+  static_assert(
+      is_same<typename __is_pathable<_InputIt>::__char_type, char>::value,
+      "u8path(Iter, Iter) requires Iter have a value_type of type 'char'");
+  return path(__f, __l);
+}
+
+class _LIBCPP_TYPE_VIS path::iterator {
+public:
+  enum _ParserState : unsigned char {
+    _Singular,
+    _BeforeBegin,
+    _InRootName,
+    _InRootDir,
+    _InFilenames,
+    _InTrailingSep,
+    _AtEnd
+  };
+
+public:
+  typedef bidirectional_iterator_tag iterator_category;
+
+  typedef path value_type;
+  typedef std::ptrdiff_t difference_type;
+  typedef const path* pointer;
+  typedef const path& reference;
+
+  typedef void
+      __stashing_iterator_tag; // See reverse_iterator and __is_stashing_iterator
+
+public:
+  _LIBCPP_INLINE_VISIBILITY
+  iterator()
+      : __stashed_elem_(), __path_ptr_(nullptr), __entry_(),
+        __state_(_Singular) {}
+
+  iterator(const iterator&) = default;
+  ~iterator() = default;
+
+  iterator& operator=(const iterator&) = default;
+
+  _LIBCPP_INLINE_VISIBILITY
+  reference operator*() const { return __stashed_elem_; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  pointer operator->() const { return &__stashed_elem_; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  iterator& operator++() {
+    _LIBCPP_ASSERT(__state_ != _Singular,
+                   "attempting to increment a singular iterator");
+    _LIBCPP_ASSERT(__state_ != _AtEnd,
+                   "attempting to increment the end iterator");
+    return __increment();
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  iterator operator++(int) {
+    iterator __it(*this);
+    this->operator++();
+    return __it;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  iterator& operator--() {
+    _LIBCPP_ASSERT(__state_ != _Singular,
+                   "attempting to decrement a singular iterator");
+    _LIBCPP_ASSERT(__entry_.data() != __path_ptr_->native().data(),
+                   "attempting to decrement the begin iterator");
+    return __decrement();
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  iterator operator--(int) {
+    iterator __it(*this);
+    this->operator--();
+    return __it;
+  }
+
+private:
+  friend class path;
+
+  inline _LIBCPP_INLINE_VISIBILITY friend bool operator==(const iterator&,
+                                                          const iterator&);
+
+  iterator& __increment();
+  iterator& __decrement();
+
+  path __stashed_elem_;
+  const path* __path_ptr_;
+  path::__string_view __entry_;
+  _ParserState __state_;
+};
+
+inline _LIBCPP_INLINE_VISIBILITY bool operator==(const path::iterator& __lhs,
+                                                 const path::iterator& __rhs) {
+  return __lhs.__path_ptr_ == __rhs.__path_ptr_ &&
+         __lhs.__entry_.data() == __rhs.__entry_.data();
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool operator!=(const path::iterator& __lhs,
+                                                 const path::iterator& __rhs) {
+  return !(__lhs == __rhs);
+}
+
+class _LIBCPP_EXCEPTION_ABI filesystem_error : public system_error {
+public:
+  _LIBCPP_INLINE_VISIBILITY
+  filesystem_error(const string& __what, error_code __ec)
+      : system_error(__ec, __what),
+        __storage_(make_shared<_Storage>(path(), path())) {
+    __create_what(0);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  filesystem_error(const string& __what, const path& __p1, error_code __ec)
+      : system_error(__ec, __what),
+        __storage_(make_shared<_Storage>(__p1, path())) {
+    __create_what(1);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  filesystem_error(const string& __what, const path& __p1, const path& __p2,
+                   error_code __ec)
+      : system_error(__ec, __what),
+        __storage_(make_shared<_Storage>(__p1, __p2)) {
+    __create_what(2);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  const path& path1() const noexcept { return __storage_->__p1_; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  const path& path2() const noexcept { return __storage_->__p2_; }
+
+  ~filesystem_error() override; // key function
+
+  _LIBCPP_INLINE_VISIBILITY
+  const char* what() const noexcept override {
+    return __storage_->__what_.c_str();
+  }
+
+  _LIBCPP_FUNC_VIS
+  void __create_what(int __num_paths);
+
+private:
+  struct _Storage {
+    _LIBCPP_INLINE_VISIBILITY
+    _Storage(const path& __p1, const path& __p2) : __p1_(__p1), __p2_(__p2) {}
+
+    path __p1_;
+    path __p2_;
+    string __what_;
+  };
+  shared_ptr<_Storage> __storage_;
+};
+
+template <class... _Args>
+_LIBCPP_NORETURN inline _LIBCPP_INLINE_VISIBILITY
+#ifndef _LIBCPP_NO_EXCEPTIONS
+    void
+    __throw_filesystem_error(_Args&&... __args) {
+  throw filesystem_error(std::forward<_Args>(__args)...);
+}
+#else
+    void
+    __throw_filesystem_error(_Args&&...) {
+  _VSTD::abort();
+}
+#endif
+
+// operational functions
+
+_LIBCPP_FUNC_VIS
+path __absolute(const path&, error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+path __canonical(const path&, error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+void __copy(const path& __from, const path& __to, copy_options __opt,
+            error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+bool __copy_file(const path& __from, const path& __to, copy_options __opt,
+                 error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+void __copy_symlink(const path& __existing_symlink, const path& __new_symlink,
+                    error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+bool __create_directories(const path& p, error_code* ec = nullptr);
+_LIBCPP_FUNC_VIS
+bool __create_directory(const path& p, error_code* ec = nullptr);
+_LIBCPP_FUNC_VIS
+bool __create_directory(const path& p, const path& attributes,
+                        error_code* ec = nullptr);
+_LIBCPP_FUNC_VIS
+void __create_directory_symlink(const path& __to, const path& __new_symlink,
+                                error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+void __create_hard_link(const path& __to, const path& __new_hard_link,
+                        error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+void __create_symlink(const path& __to, const path& __new_symlink,
+                      error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+path __current_path(error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+void __current_path(const path&, error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+bool __equivalent(const path&, const path&, error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+uintmax_t __file_size(const path&, error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+uintmax_t __hard_link_count(const path&, error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+bool __fs_is_empty(const path& p, error_code* ec = nullptr);
+_LIBCPP_FUNC_VIS
+file_time_type __last_write_time(const path& p, error_code* ec = nullptr);
+_LIBCPP_FUNC_VIS
+void __last_write_time(const path& p, file_time_type new_time,
+                       error_code* ec = nullptr);
+_LIBCPP_FUNC_VIS
+void __permissions(const path&, perms, perm_options, error_code* = nullptr);
+_LIBCPP_FUNC_VIS
+path __read_symlink(const path& p, error_code* ec = nullptr);
+_LIBCPP_FUNC_VIS
+bool __remove(const path& p, error_code* ec = nullptr);
+_LIBCPP_FUNC_VIS
+uintmax_t __remove_all(const path& p, error_code* ec = nullptr);
+_LIBCPP_FUNC_VIS
+void __rename(const path& from, const path& to, error_code* ec = nullptr);
+_LIBCPP_FUNC_VIS
+void __resize_file(const path& p, uintmax_t size, error_code* ec = nullptr);
+_LIBCPP_FUNC_VIS
+space_info __space(const path&, error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+file_status __status(const path&, error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+file_status __symlink_status(const path&, error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+path __system_complete(const path&, error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+path __temp_directory_path(error_code* __ec = nullptr);
+_LIBCPP_FUNC_VIS
+path __weakly_canonical(path const& __p, error_code* __ec = nullptr);
+
+inline _LIBCPP_INLINE_VISIBILITY path current_path() {
+  return __current_path();
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path current_path(error_code& __ec) {
+  return __current_path(&__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void current_path(const path& __p) {
+  __current_path(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void current_path(const path& __p,
+                                                   error_code& __ec) noexcept {
+  __current_path(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path absolute(const path& __p) {
+  return __absolute(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path absolute(const path& __p,
+                                               error_code& __ec) {
+  return __absolute(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path canonical(const path& __p) {
+  return __canonical(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path canonical(const path& __p,
+                                                error_code& __ec) {
+  return __canonical(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void copy(const path& __from,
+                                           const path& __to) {
+  __copy(__from, __to, copy_options::none);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void copy(const path& __from, const path& __to,
+                                           error_code& __ec) {
+  __copy(__from, __to, copy_options::none, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void copy(const path& __from, const path& __to,
+                                           copy_options __opt) {
+  __copy(__from, __to, __opt);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void copy(const path& __from, const path& __to,
+                                           copy_options __opt,
+                                           error_code& __ec) {
+  __copy(__from, __to, __opt, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool copy_file(const path& __from,
+                                                const path& __to) {
+  return __copy_file(__from, __to, copy_options::none);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool
+copy_file(const path& __from, const path& __to, error_code& __ec) {
+  return __copy_file(__from, __to, copy_options::none, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool
+copy_file(const path& __from, const path& __to, copy_options __opt) {
+  return __copy_file(__from, __to, __opt);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool copy_file(const path& __from,
+                                                const path& __to,
+                                                copy_options __opt,
+                                                error_code& __ec) {
+  return __copy_file(__from, __to, __opt, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void copy_symlink(const path& __existing,
+                                                   const path& __new) {
+  __copy_symlink(__existing, __new);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void
+copy_symlink(const path& __ext, const path& __new, error_code& __ec) noexcept {
+  __copy_symlink(__ext, __new, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool create_directories(const path& __p) {
+  return __create_directories(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool create_directories(const path& __p,
+                                                         error_code& __ec) {
+  return __create_directories(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool create_directory(const path& __p) {
+  return __create_directory(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool
+create_directory(const path& __p, error_code& __ec) noexcept {
+  return __create_directory(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool create_directory(const path& __p,
+                                                       const path& __attrs) {
+  return __create_directory(__p, __attrs);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool
+create_directory(const path& __p, const path& __attrs,
+                 error_code& __ec) noexcept {
+  return __create_directory(__p, __attrs, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void
+create_directory_symlink(const path& __to, const path& __new) {
+  __create_directory_symlink(__to, __new);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void
+create_directory_symlink(const path& __to, const path& __new,
+                         error_code& __ec) noexcept {
+  __create_directory_symlink(__to, __new, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void create_hard_link(const path& __to,
+                                                       const path& __new) {
+  __create_hard_link(__to, __new);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void
+create_hard_link(const path& __to, const path& __new,
+                 error_code& __ec) noexcept {
+  __create_hard_link(__to, __new, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void create_symlink(const path& __to,
+                                                     const path& __new) {
+  __create_symlink(__to, __new);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void
+create_symlink(const path& __to, const path& __new, error_code& __ec) noexcept {
+  return __create_symlink(__to, __new, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool status_known(file_status __s) noexcept {
+  return __s.type() != file_type::none;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool exists(file_status __s) noexcept {
+  return status_known(__s) && __s.type() != file_type::not_found;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool exists(const path& __p) {
+  return exists(__status(__p));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool exists(const path& __p,
+                                             error_code& __ec) noexcept {
+  auto __s = __status(__p, &__ec);
+  if (status_known(__s))
+    __ec.clear();
+  return exists(__s);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool equivalent(const path& __p1,
+                                                 const path& __p2) {
+  return __equivalent(__p1, __p2);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool
+equivalent(const path& __p1, const path& __p2, error_code& __ec) noexcept {
+  return __equivalent(__p1, __p2, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY uintmax_t file_size(const path& __p) {
+  return __file_size(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY uintmax_t
+file_size(const path& __p, error_code& __ec) noexcept {
+  return __file_size(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY uintmax_t hard_link_count(const path& __p) {
+  return __hard_link_count(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY uintmax_t
+hard_link_count(const path& __p, error_code& __ec) noexcept {
+  return __hard_link_count(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_block_file(file_status __s) noexcept {
+  return __s.type() == file_type::block;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_block_file(const path& __p) {
+  return is_block_file(__status(__p));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_block_file(const path& __p,
+                                                    error_code& __ec) noexcept {
+  return is_block_file(__status(__p, &__ec));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool
+is_character_file(file_status __s) noexcept {
+  return __s.type() == file_type::character;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_character_file(const path& __p) {
+  return is_character_file(__status(__p));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool
+is_character_file(const path& __p, error_code& __ec) noexcept {
+  return is_character_file(__status(__p, &__ec));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_directory(file_status __s) noexcept {
+  return __s.type() == file_type::directory;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_directory(const path& __p) {
+  return is_directory(__status(__p));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_directory(const path& __p,
+                                                   error_code& __ec) noexcept {
+  return is_directory(__status(__p, &__ec));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_empty(const path& __p) {
+  return __fs_is_empty(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_empty(const path& __p,
+                                               error_code& __ec) {
+  return __fs_is_empty(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_fifo(file_status __s) noexcept {
+  return __s.type() == file_type::fifo;
+}
+inline _LIBCPP_INLINE_VISIBILITY bool is_fifo(const path& __p) {
+  return is_fifo(__status(__p));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_fifo(const path& __p,
+                                              error_code& __ec) noexcept {
+  return is_fifo(__status(__p, &__ec));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool
+is_regular_file(file_status __s) noexcept {
+  return __s.type() == file_type::regular;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_regular_file(const path& __p) {
+  return is_regular_file(__status(__p));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool
+is_regular_file(const path& __p, error_code& __ec) noexcept {
+  return is_regular_file(__status(__p, &__ec));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_socket(file_status __s) noexcept {
+  return __s.type() == file_type::socket;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_socket(const path& __p) {
+  return is_socket(__status(__p));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_socket(const path& __p,
+                                                error_code& __ec) noexcept {
+  return is_socket(__status(__p, &__ec));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_symlink(file_status __s) noexcept {
+  return __s.type() == file_type::symlink;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_symlink(const path& __p) {
+  return is_symlink(__symlink_status(__p));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_symlink(const path& __p,
+                                                 error_code& __ec) noexcept {
+  return is_symlink(__symlink_status(__p, &__ec));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_other(file_status __s) noexcept {
+  return exists(__s) && !is_regular_file(__s) && !is_directory(__s) &&
+         !is_symlink(__s);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_other(const path& __p) {
+  return is_other(__status(__p));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool is_other(const path& __p,
+                                               error_code& __ec) noexcept {
+  return is_other(__status(__p, &__ec));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY file_time_type
+last_write_time(const path& __p) {
+  return __last_write_time(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY file_time_type
+last_write_time(const path& __p, error_code& __ec) noexcept {
+  return __last_write_time(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void last_write_time(const path& __p,
+                                                      file_time_type __t) {
+  __last_write_time(__p, __t);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void
+last_write_time(const path& __p, file_time_type __t,
+                error_code& __ec) noexcept {
+  __last_write_time(__p, __t, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void
+permissions(const path& __p, perms __prms,
+            perm_options __opts = perm_options::replace) {
+  __permissions(__p, __prms, __opts);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void permissions(const path& __p, perms __prms,
+                                                  error_code& __ec) noexcept {
+  __permissions(__p, __prms, perm_options::replace, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void permissions(const path& __p, perms __prms,
+                                                  perm_options __opts,
+                                                  error_code& __ec) {
+  __permissions(__p, __prms, __opts, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path proximate(const path& __p,
+                                                const path& __base,
+                                                error_code& __ec) {
+  path __tmp = __weakly_canonical(__p, &__ec);
+  if (__ec)
+    return {};
+  path __tmp_base = __weakly_canonical(__base, &__ec);
+  if (__ec)
+    return {};
+  return __tmp.lexically_proximate(__tmp_base);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path proximate(const path& __p,
+                                                error_code& __ec) {
+  return proximate(__p, current_path(), __ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path
+proximate(const path& __p, const path& __base = current_path()) {
+  return __weakly_canonical(__p).lexically_proximate(
+      __weakly_canonical(__base));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path read_symlink(const path& __p) {
+  return __read_symlink(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path read_symlink(const path& __p,
+                                                   error_code& __ec) {
+  return __read_symlink(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path relative(const path& __p,
+                                               const path& __base,
+                                               error_code& __ec) {
+  path __tmp = __weakly_canonical(__p, &__ec);
+  if (__ec)
+    return path();
+  path __tmpbase = __weakly_canonical(__base, &__ec);
+  if (__ec)
+    return path();
+  return __tmp.lexically_relative(__tmpbase);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path relative(const path& __p,
+                                               error_code& __ec) {
+  return relative(__p, current_path(), __ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path
+relative(const path& __p, const path& __base = current_path()) {
+  return __weakly_canonical(__p).lexically_relative(__weakly_canonical(__base));
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool remove(const path& __p) {
+  return __remove(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool remove(const path& __p,
+                                             error_code& __ec) noexcept {
+  return __remove(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY uintmax_t remove_all(const path& __p) {
+  return __remove_all(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY uintmax_t remove_all(const path& __p,
+                                                      error_code& __ec) {
+  return __remove_all(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void rename(const path& __from,
+                                             const path& __to) {
+  return __rename(__from, __to);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void
+rename(const path& __from, const path& __to, error_code& __ec) noexcept {
+  return __rename(__from, __to, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void resize_file(const path& __p,
+                                                  uintmax_t __ns) {
+  return __resize_file(__p, __ns);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY void
+resize_file(const path& __p, uintmax_t __ns, error_code& __ec) noexcept {
+  return __resize_file(__p, __ns, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY space_info space(const path& __p) {
+  return __space(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY space_info space(const path& __p,
+                                                  error_code& __ec) noexcept {
+  return __space(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY file_status status(const path& __p) {
+  return __status(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY file_status status(const path& __p,
+                                                    error_code& __ec) noexcept {
+  return __status(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY file_status symlink_status(const path& __p) {
+  return __symlink_status(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY file_status
+symlink_status(const path& __p, error_code& __ec) noexcept {
+  return __symlink_status(__p, &__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path temp_directory_path() {
+  return __temp_directory_path();
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path temp_directory_path(error_code& __ec) {
+  return __temp_directory_path(&__ec);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path weakly_canonical(path const& __p) {
+  return __weakly_canonical(__p);
+}
+
+inline _LIBCPP_INLINE_VISIBILITY path weakly_canonical(path const& __p,
+                                                       error_code& __ec) {
+  return __weakly_canonical(__p, &__ec);
+}
+
+class directory_iterator;
+class recursive_directory_iterator;
+class __dir_stream;
+
+class directory_entry {
+  typedef _VSTD_FS::path _Path;
+
+public:
+  // constructors and destructors
+  directory_entry() noexcept = default;
+  directory_entry(directory_entry const&) = default;
+  directory_entry(directory_entry&&) noexcept = default;
+
+  _LIBCPP_INLINE_VISIBILITY
+  explicit directory_entry(_Path const& __p) : __p_(__p) {
+    error_code __ec;
+    __refresh(&__ec);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  directory_entry(_Path const& __p, error_code& __ec) : __p_(__p) {
+    __refresh(&__ec);
+  }
+
+  ~directory_entry() {}
+
+  directory_entry& operator=(directory_entry const&) = default;
+  directory_entry& operator=(directory_entry&&) noexcept = default;
+
+  _LIBCPP_INLINE_VISIBILITY
+  void assign(_Path const& __p) {
+    __p_ = __p;
+    error_code __ec;
+    __refresh(&__ec);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  void assign(_Path const& __p, error_code& __ec) {
+    __p_ = __p;
+    __refresh(&__ec);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  void replace_filename(_Path const& __p) {
+    __p_.replace_filename(__p);
+    error_code __ec;
+    __refresh(&__ec);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  void replace_filename(_Path const& __p, error_code& __ec) {
+    __p_ = __p_.parent_path() / __p;
+    __refresh(&__ec);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  void refresh() { __refresh(); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  void refresh(error_code& __ec) noexcept { __refresh(&__ec); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  _Path const& path() const noexcept { return __p_; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  operator const _Path&() const noexcept { return __p_; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool exists() const { return _VSTD_FS::exists(file_status{__get_ft()}); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool exists(error_code& __ec) const noexcept {
+    return _VSTD_FS::exists(file_status{__get_ft(&__ec)});
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_block_file() const { return __get_ft() == file_type::block; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_block_file(error_code& __ec) const noexcept {
+    return __get_ft(&__ec) == file_type::block;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_character_file() const { return __get_ft() == file_type::character; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_character_file(error_code& __ec) const noexcept {
+    return __get_ft(&__ec) == file_type::character;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_directory() const { return __get_ft() == file_type::directory; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_directory(error_code& __ec) const noexcept {
+    return __get_ft(&__ec) == file_type::directory;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_fifo() const { return __get_ft() == file_type::fifo; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_fifo(error_code& __ec) const noexcept {
+    return __get_ft(&__ec) == file_type::fifo;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_other() const { return _VSTD_FS::is_other(file_status{__get_ft()}); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_other(error_code& __ec) const noexcept {
+    return _VSTD_FS::is_other(file_status{__get_ft(&__ec)});
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_regular_file() const { return __get_ft() == file_type::regular; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_regular_file(error_code& __ec) const noexcept {
+    return __get_ft(&__ec) == file_type::regular;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_socket() const { return __get_ft() == file_type::socket; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_socket(error_code& __ec) const noexcept {
+    return __get_ft(&__ec) == file_type::socket;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_symlink() const { return __get_sym_ft() == file_type::symlink; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool is_symlink(error_code& __ec) const noexcept {
+    return __get_sym_ft(&__ec) == file_type::symlink;
+  }
+  _LIBCPP_INLINE_VISIBILITY
+  uintmax_t file_size() const { return __get_size(); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  uintmax_t file_size(error_code& __ec) const noexcept {
+    return __get_size(&__ec);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  uintmax_t hard_link_count() const { return __get_nlink(); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  uintmax_t hard_link_count(error_code& __ec) const noexcept {
+    return __get_nlink(&__ec);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  file_time_type last_write_time() const { return __get_write_time(); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  file_time_type last_write_time(error_code& __ec) const noexcept {
+    return __get_write_time(&__ec);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  file_status status() const { return __get_status(); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  file_status status(error_code& __ec) const noexcept {
+    return __get_status(&__ec);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  file_status symlink_status() const { return __get_symlink_status(); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  file_status symlink_status(error_code& __ec) const noexcept {
+    return __get_symlink_status(&__ec);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool operator<(directory_entry const& __rhs) const noexcept {
+    return __p_ < __rhs.__p_;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool operator==(directory_entry const& __rhs) const noexcept {
+    return __p_ == __rhs.__p_;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool operator!=(directory_entry const& __rhs) const noexcept {
+    return __p_ != __rhs.__p_;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool operator<=(directory_entry const& __rhs) const noexcept {
+    return __p_ <= __rhs.__p_;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool operator>(directory_entry const& __rhs) const noexcept {
+    return __p_ > __rhs.__p_;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool operator>=(directory_entry const& __rhs) const noexcept {
+    return __p_ >= __rhs.__p_;
+  }
+
+private:
+  friend class directory_iterator;
+  friend class recursive_directory_iterator;
+  friend class __dir_stream;
+
+  enum _CacheType : unsigned char {
+    _Empty,
+    _IterSymlink,
+    _IterNonSymlink,
+    _RefreshSymlink,
+    _RefreshSymlinkUnresolved,
+    _RefreshNonSymlink
+  };
+
+  struct __cached_data {
+    uintmax_t __size_;
+    uintmax_t __nlink_;
+    file_time_type __write_time_;
+    perms __sym_perms_;
+    perms __non_sym_perms_;
+    file_type __type_;
+    _CacheType __cache_type_;
+
+    _LIBCPP_INLINE_VISIBILITY
+    __cached_data() noexcept { __reset(); }
+
+    _LIBCPP_INLINE_VISIBILITY
+    void __reset() {
+      __cache_type_ = _Empty;
+      __type_ = file_type::none;
+      __sym_perms_ = __non_sym_perms_ = perms::unknown;
+      __size_ = __nlink_ = uintmax_t(-1);
+      __write_time_ = file_time_type::min();
+    }
+  };
+
+  _LIBCPP_INLINE_VISIBILITY
+  static __cached_data __create_iter_result(file_type __ft) {
+    __cached_data __data;
+    __data.__type_ = __ft;
+    __data.__cache_type_ = [&]() {
+      switch (__ft) {
+      case file_type::none:
+        return _Empty;
+      case file_type::symlink:
+        return _IterSymlink;
+      default:
+        return _IterNonSymlink;
+      }
+    }();
+    return __data;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  void __assign_iter_entry(_Path&& __p, __cached_data __dt) {
+    __p_ = std::move(__p);
+    __data_ = __dt;
+  }
+
+  _LIBCPP_FUNC_VIS
+  error_code __do_refresh() noexcept;
+
+  _LIBCPP_INLINE_VISIBILITY
+  static bool __is_dne_error(error_code const& __ec) {
+    if (!__ec)
+      return true;
+    switch (static_cast<errc>(__ec.value())) {
+    case errc::no_such_file_or_directory:
+    case errc::not_a_directory:
+      return true;
+    default:
+      return false;
+    }
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  void __handle_error(const char* __msg, error_code* __dest_ec,
+                      error_code const& __ec, bool __allow_dne = false) const {
+    if (__dest_ec) {
+      *__dest_ec = __ec;
+      return;
+    }
+    if (__ec && (!__allow_dne || !__is_dne_error(__ec)))
+      __throw_filesystem_error(__msg, __p_, __ec);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  void __refresh(error_code* __ec = nullptr) {
+    __handle_error("in directory_entry::refresh", __ec, __do_refresh(),
+                   /*allow_dne*/ true);
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  file_type __get_sym_ft(error_code* __ec = nullptr) const {
+    switch (__data_.__cache_type_) {
+    case _Empty:
+      return __symlink_status(__p_, __ec).type();
+    case _IterSymlink:
+    case _RefreshSymlink:
+    case _RefreshSymlinkUnresolved:
+      if (__ec)
+        __ec->clear();
+      return file_type::symlink;
+    case _IterNonSymlink:
+    case _RefreshNonSymlink:
+      file_status __st(__data_.__type_);
+      if (__ec && !_VSTD_FS::exists(__st))
+        *__ec = make_error_code(errc::no_such_file_or_directory);
+      else if (__ec)
+        __ec->clear();
+      return __data_.__type_;
+    }
+    _LIBCPP_UNREACHABLE();
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  file_type __get_ft(error_code* __ec = nullptr) const {
+    switch (__data_.__cache_type_) {
+    case _Empty:
+    case _IterSymlink:
+    case _RefreshSymlinkUnresolved:
+      return __status(__p_, __ec).type();
+    case _IterNonSymlink:
+    case _RefreshNonSymlink:
+    case _RefreshSymlink: {
+      file_status __st(__data_.__type_);
+      if (__ec && !_VSTD_FS::exists(__st))
+        *__ec = make_error_code(errc::no_such_file_or_directory);
+      else if (__ec)
+        __ec->clear();
+      return __data_.__type_;
+    }
+    }
+    _LIBCPP_UNREACHABLE();
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  file_status __get_status(error_code* __ec = nullptr) const {
+    switch (__data_.__cache_type_) {
+    case _Empty:
+    case _IterNonSymlink:
+    case _IterSymlink:
+    case _RefreshSymlinkUnresolved:
+      return __status(__p_, __ec);
+    case _RefreshNonSymlink:
+    case _RefreshSymlink:
+      return file_status(__get_ft(__ec), __data_.__non_sym_perms_);
+    }
+    _LIBCPP_UNREACHABLE();
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  file_status __get_symlink_status(error_code* __ec = nullptr) const {
+    switch (__data_.__cache_type_) {
+    case _Empty:
+    case _IterNonSymlink:
+    case _IterSymlink:
+      return __symlink_status(__p_, __ec);
+    case _RefreshNonSymlink:
+      return file_status(__get_sym_ft(__ec), __data_.__non_sym_perms_);
+    case _RefreshSymlink:
+    case _RefreshSymlinkUnresolved:
+      return file_status(__get_sym_ft(__ec), __data_.__sym_perms_);
+    }
+    _LIBCPP_UNREACHABLE();
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  uintmax_t __get_size(error_code* __ec = nullptr) const {
+    switch (__data_.__cache_type_) {
+    case _Empty:
+    case _IterNonSymlink:
+    case _IterSymlink:
+    case _RefreshSymlinkUnresolved:
+      return _VSTD_FS::__file_size(__p_, __ec);
+    case _RefreshSymlink:
+    case _RefreshNonSymlink: {
+      error_code __m_ec;
+      file_status __st(__get_ft(&__m_ec));
+      __handle_error("in directory_entry::file_size", __ec, __m_ec);
+      if (_VSTD_FS::exists(__st) && !_VSTD_FS::is_regular_file(__st)) {
+        errc __err_kind = _VSTD_FS::is_directory(__st) ? errc::is_a_directory
+                                                       : errc::not_supported;
+        __handle_error("in directory_entry::file_size", __ec,
+                       make_error_code(__err_kind));
+      }
+      return __data_.__size_;
+    }
+    }
+    _LIBCPP_UNREACHABLE();
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  uintmax_t __get_nlink(error_code* __ec = nullptr) const {
+    switch (__data_.__cache_type_) {
+    case _Empty:
+    case _IterNonSymlink:
+    case _IterSymlink:
+    case _RefreshSymlinkUnresolved:
+      return _VSTD_FS::__hard_link_count(__p_, __ec);
+    case _RefreshSymlink:
+    case _RefreshNonSymlink: {
+      error_code __m_ec;
+      (void)__get_ft(&__m_ec);
+      __handle_error("in directory_entry::hard_link_count", __ec, __m_ec);
+      return __data_.__nlink_;
+    }
+    }
+    _LIBCPP_UNREACHABLE();
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  file_time_type __get_write_time(error_code* __ec = nullptr) const {
+    switch (__data_.__cache_type_) {
+    case _Empty:
+    case _IterNonSymlink:
+    case _IterSymlink:
+    case _RefreshSymlinkUnresolved:
+      return _VSTD_FS::__last_write_time(__p_, __ec);
+    case _RefreshSymlink:
+    case _RefreshNonSymlink: {
+      error_code __m_ec;
+      file_status __st(__get_ft(&__m_ec));
+      __handle_error("in directory_entry::last_write_time", __ec, __m_ec);
+      if (_VSTD_FS::exists(__st) &&
+          __data_.__write_time_ == file_time_type::min())
+        __handle_error("in directory_entry::last_write_time", __ec,
+                       make_error_code(errc::value_too_large));
+      return __data_.__write_time_;
+    }
+    }
+    _LIBCPP_UNREACHABLE();
+  }
+
+private:
+  _Path __p_;
+  __cached_data __data_;
+};
+
+class __dir_element_proxy {
+public:
+  inline _LIBCPP_INLINE_VISIBILITY directory_entry operator*() {
+    return _VSTD::move(__elem_);
+  }
+
+private:
+  friend class directory_iterator;
+  friend class recursive_directory_iterator;
+  explicit __dir_element_proxy(directory_entry const& __e) : __elem_(__e) {}
+  __dir_element_proxy(__dir_element_proxy&& __o)
+      : __elem_(_VSTD::move(__o.__elem_)) {}
+  directory_entry __elem_;
+};
+
+class directory_iterator {
+public:
+  typedef directory_entry value_type;
+  typedef ptrdiff_t difference_type;
+  typedef value_type const* pointer;
+  typedef value_type const& reference;
+  typedef input_iterator_tag iterator_category;
+
+public:
+  //ctor & dtor
+  directory_iterator() noexcept {}
+
+  explicit directory_iterator(const path& __p)
+      : directory_iterator(__p, nullptr) {}
+
+  directory_iterator(const path& __p, directory_options __opts)
+      : directory_iterator(__p, nullptr, __opts) {}
+
+  directory_iterator(const path& __p, error_code& __ec)
+      : directory_iterator(__p, &__ec) {}
+
+  directory_iterator(const path& __p, directory_options __opts,
+                     error_code& __ec)
+      : directory_iterator(__p, &__ec, __opts) {}
+
+  directory_iterator(const directory_iterator&) = default;
+  directory_iterator(directory_iterator&&) = default;
+  directory_iterator& operator=(const directory_iterator&) = default;
+
+  directory_iterator& operator=(directory_iterator&& __o) noexcept {
+    // non-default implementation provided to support self-move assign.
+    if (this != &__o) {
+      __imp_ = _VSTD::move(__o.__imp_);
+    }
+    return *this;
+  }
+
+  ~directory_iterator() = default;
+
+  const directory_entry& operator*() const {
+    _LIBCPP_ASSERT(__imp_, "The end iterator cannot be dereferenced");
+    return __dereference();
+  }
+
+  const directory_entry* operator->() const { return &**this; }
+
+  directory_iterator& operator++() { return __increment(); }
+
+  __dir_element_proxy operator++(int) {
+    __dir_element_proxy __p(**this);
+    __increment();
+    return __p;
+  }
+
+  directory_iterator& increment(error_code& __ec) { return __increment(&__ec); }
+
+private:
+  inline _LIBCPP_INLINE_VISIBILITY friend bool
+  operator==(const directory_iterator& __lhs,
+             const directory_iterator& __rhs) noexcept;
+
+  // construct the dir_stream
+  _LIBCPP_FUNC_VIS
+  directory_iterator(const path&, error_code*,
+                     directory_options = directory_options::none);
+
+  _LIBCPP_FUNC_VIS
+  directory_iterator& __increment(error_code* __ec = nullptr);
+
+  _LIBCPP_FUNC_VIS
+  const directory_entry& __dereference() const;
+
+private:
+  shared_ptr<__dir_stream> __imp_;
+};
+
+inline _LIBCPP_INLINE_VISIBILITY bool
+operator==(const directory_iterator& __lhs,
+           const directory_iterator& __rhs) noexcept {
+  return __lhs.__imp_ == __rhs.__imp_;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY bool
+operator!=(const directory_iterator& __lhs,
+           const directory_iterator& __rhs) noexcept {
+  return !(__lhs == __rhs);
+}
+
+// enable directory_iterator range-based for statements
+inline _LIBCPP_INLINE_VISIBILITY directory_iterator
+begin(directory_iterator __iter) noexcept {
+  return __iter;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY directory_iterator
+end(const directory_iterator&) noexcept {
+  return directory_iterator();
+}
+
+class recursive_directory_iterator {
+public:
+  using value_type = directory_entry;
+  using difference_type = std::ptrdiff_t;
+  using pointer = directory_entry const*;
+  using reference = directory_entry const&;
+  using iterator_category = std::input_iterator_tag;
+
+public:
+  // constructors and destructor
+  _LIBCPP_INLINE_VISIBILITY
+  recursive_directory_iterator() noexcept : __rec_(false) {}
+
+  _LIBCPP_INLINE_VISIBILITY
+  explicit recursive_directory_iterator(
+      const path& __p, directory_options __xoptions = directory_options::none)
+      : recursive_directory_iterator(__p, __xoptions, nullptr) {}
+
+  _LIBCPP_INLINE_VISIBILITY
+  recursive_directory_iterator(const path& __p, directory_options __xoptions,
+                               error_code& __ec)
+      : recursive_directory_iterator(__p, __xoptions, &__ec) {}
+
+  _LIBCPP_INLINE_VISIBILITY
+  recursive_directory_iterator(const path& __p, error_code& __ec)
+      : recursive_directory_iterator(__p, directory_options::none, &__ec) {}
+
+  recursive_directory_iterator(const recursive_directory_iterator&) = default;
+  recursive_directory_iterator(recursive_directory_iterator&&) = default;
+
+  recursive_directory_iterator&
+  operator=(const recursive_directory_iterator&) = default;
+
+  _LIBCPP_INLINE_VISIBILITY
+  recursive_directory_iterator&
+  operator=(recursive_directory_iterator&& __o) noexcept {
+    // non-default implementation provided to support self-move assign.
+    if (this != &__o) {
+      __imp_ = _VSTD::move(__o.__imp_);
+      __rec_ = __o.__rec_;
+    }
+    return *this;
+  }
+
+  ~recursive_directory_iterator() = default;
+
+  _LIBCPP_INLINE_VISIBILITY
+  const directory_entry& operator*() const { return __dereference(); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  const directory_entry* operator->() const { return &__dereference(); }
+
+  recursive_directory_iterator& operator++() { return __increment(); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  __dir_element_proxy operator++(int) {
+    __dir_element_proxy __p(**this);
+    __increment();
+    return __p;
+  }
+
+  _LIBCPP_INLINE_VISIBILITY
+  recursive_directory_iterator& increment(error_code& __ec) {
+    return __increment(&__ec);
+  }
+
+  _LIBCPP_FUNC_VIS directory_options options() const;
+  _LIBCPP_FUNC_VIS int depth() const;
+
+  _LIBCPP_INLINE_VISIBILITY
+  void pop() { __pop(); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  void pop(error_code& __ec) { __pop(&__ec); }
+
+  _LIBCPP_INLINE_VISIBILITY
+  bool recursion_pending() const { return __rec_; }
+
+  _LIBCPP_INLINE_VISIBILITY
+  void disable_recursion_pending() { __rec_ = false; }
+
+private:
+  recursive_directory_iterator(const path& __p, directory_options __opt,
+                               error_code* __ec);
+
+  _LIBCPP_FUNC_VIS
+  const directory_entry& __dereference() const;
+
+  _LIBCPP_FUNC_VIS
+  bool __try_recursion(error_code* __ec);
+
+  _LIBCPP_FUNC_VIS
+  void __advance(error_code* __ec = nullptr);
+
+  _LIBCPP_FUNC_VIS
+  recursive_directory_iterator& __increment(error_code* __ec = nullptr);
+
+  _LIBCPP_FUNC_VIS
+  void __pop(error_code* __ec = nullptr);
+
+  inline _LIBCPP_INLINE_VISIBILITY friend bool
+  operator==(const recursive_directory_iterator&,
+             const recursive_directory_iterator&) noexcept;
+
+  struct __shared_imp;
+  shared_ptr<__shared_imp> __imp_;
+  bool __rec_;
+}; // class recursive_directory_iterator
+
+inline _LIBCPP_INLINE_VISIBILITY bool
+operator==(const recursive_directory_iterator& __lhs,
+           const recursive_directory_iterator& __rhs) noexcept {
+  return __lhs.__imp_ == __rhs.__imp_;
+}
+
+_LIBCPP_INLINE_VISIBILITY
+inline bool operator!=(const recursive_directory_iterator& __lhs,
+                       const recursive_directory_iterator& __rhs) noexcept {
+  return !(__lhs == __rhs);
+}
+// enable recursive_directory_iterator range-based for statements
+inline _LIBCPP_INLINE_VISIBILITY recursive_directory_iterator
+begin(recursive_directory_iterator __iter) noexcept {
+  return __iter;
+}
+
+inline _LIBCPP_INLINE_VISIBILITY recursive_directory_iterator
+end(const recursive_directory_iterator&) noexcept {
+  return recursive_directory_iterator();
+}
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
+
+#endif // !_LIBCPP_CXX03_LANG
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP_FILESYSTEM
diff --git a/include/fstream b/include/fstream
index 8b9aefa..332b474 100644
--- a/include/fstream
+++ b/include/fstream
@@ -38,6 +38,7 @@
     bool is_open() const;
     basic_filebuf* open(const char* s, ios_base::openmode mode);
     basic_filebuf* open(const string& s, ios_base::openmode mode);
+    basic_filebuf* open(const filesystem::path& p, ios_base::openmode mode); // C++17
     basic_filebuf* close();
 
 protected:
@@ -77,6 +78,8 @@
     basic_ifstream();
     explicit basic_ifstream(const char* s, ios_base::openmode mode = ios_base::in);
     explicit basic_ifstream(const string& s, ios_base::openmode mode = ios_base::in);
+    explicit basic_ifstream(const filesystem::path& p,
+                            ios_base::openmode mode = ios_base::in); // C++17
     basic_ifstream(basic_ifstream&& rhs);
 
     basic_ifstream& operator=(basic_ifstream&& rhs);
@@ -86,6 +89,8 @@
     bool is_open() const;
     void open(const char* s, ios_base::openmode mode = ios_base::in);
     void open(const string& s, ios_base::openmode mode = ios_base::in);
+    void open(const filesystem::path& s, ios_base::openmode mode = ios_base::in); // C++17
+
     void close();
 };
 
@@ -110,6 +115,8 @@
     basic_ofstream();
     explicit basic_ofstream(const char* s, ios_base::openmode mode = ios_base::out);
     explicit basic_ofstream(const string& s, ios_base::openmode mode = ios_base::out);
+    explicit basic_ofstream(const filesystem::path& p,
+                            ios_base::openmode mode = ios_base::out); // C++17
     basic_ofstream(basic_ofstream&& rhs);
 
     basic_ofstream& operator=(basic_ofstream&& rhs);
@@ -119,6 +126,9 @@
     bool is_open() const;
     void open(const char* s, ios_base::openmode mode = ios_base::out);
     void open(const string& s, ios_base::openmode mode = ios_base::out);
+    void open(const filesystem::path& p,
+              ios_base::openmode mode = ios_base::out); // C++17
+
     void close();
 };
 
@@ -143,6 +153,8 @@
     basic_fstream();
     explicit basic_fstream(const char* s, ios_base::openmode mode = ios_base::in|ios_base::out);
     explicit basic_fstream(const string& s, ios_base::openmode mode = ios_base::in|ios_base::out);
+    explicit basic_fstream(const filesystem::path& p,
+                           ios_base::openmode mode = ios_base::in|ios_base::out); C++17
     basic_fstream(basic_fstream&& rhs);
 
     basic_fstream& operator=(basic_fstream&& rhs);
@@ -152,6 +164,9 @@
     bool is_open() const;
     void open(const char* s, ios_base::openmode mode = ios_base::in|ios_base::out);
     void open(const string& s, ios_base::openmode mode = ios_base::in|ios_base::out);
+    void open(const filesystem::path& s,
+              ios_base::openmode mode = ios_base::in|ios_base::out); // C++17
+
     void close();
 };
 
@@ -171,6 +186,7 @@
 #include <__locale>
 #include <cstdio>
 #include <cstdlib>
+#include <filesystem>
 
 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
 #pragma GCC system_header
@@ -219,6 +235,12 @@
     _LIBCPP_INLINE_VISIBILITY
     basic_filebuf* open(const string& __s, ios_base::openmode __mode);
 
+#if _LIBCPP_STD_VER >= 17
+    _LIBCPP_INLINE_VISIBILITY
+    basic_filebuf* open(const _VSTD_FS::path& __p, ios_base::openmode __mode) {
+      return open(__p.c_str(), __mode);
+    }
+#endif
     _LIBCPP_INLINE_VISIBILITY
     basic_filebuf* __open(int __fd, ios_base::openmode __mode);
 #endif
@@ -1128,6 +1150,11 @@
 #endif
     _LIBCPP_INLINE_VISIBILITY
     explicit basic_ifstream(const string& __s, ios_base::openmode __mode = ios_base::in);
+#if _LIBCPP_STD_VER >= 17
+    _LIBCPP_INLINE_VISIBILITY
+    explicit basic_ifstream(const filesystem::path& __p, ios_base::openmode __mode = ios_base::in)
+      : basic_ifstream(__p.c_str(), __mode) {}
+#endif // _LIBCPP_STD_VER >= 17
 #endif
 #ifndef _LIBCPP_CXX03_LANG
     _LIBCPP_INLINE_VISIBILITY
@@ -1149,6 +1176,13 @@
     void open(const wchar_t* __s, ios_base::openmode __mode = ios_base::in);
 #endif
     void open(const string& __s, ios_base::openmode __mode = ios_base::in);
+#if _LIBCPP_STD_VER >= 17
+    _LIBCPP_INLINE_VISIBILITY
+    void open(const filesystem::path& __p,
+              ios_base::openmode __mode = ios_base::in) {
+      return open(__p.c_str(), __mode);
+    }
+#endif // _LIBCPP_STD_VER >= 17
 
     _LIBCPP_INLINE_VISIBILITY
     void __open(int __fd, ios_base::openmode __mode);
@@ -1329,6 +1363,13 @@
 #endif
     _LIBCPP_INLINE_VISIBILITY
     explicit basic_ofstream(const string& __s, ios_base::openmode __mode = ios_base::out);
+
+#if _LIBCPP_STD_VER >= 17
+    _LIBCPP_INLINE_VISIBILITY
+    explicit basic_ofstream(const filesystem::path& __p, ios_base::openmode __mode = ios_base::out)
+      : basic_ofstream(__p.c_str(), __mode) {}
+#endif // _LIBCPP_STD_VER >= 17
+
 #ifndef _LIBCPP_CXX03_LANG
     _LIBCPP_INLINE_VISIBILITY
     basic_ofstream(basic_ofstream&& __rhs);
@@ -1350,6 +1391,12 @@
 #endif
     void open(const string& __s, ios_base::openmode __mode = ios_base::out);
 
+#if _LIBCPP_STD_VER >= 17
+    _LIBCPP_INLINE_VISIBILITY
+    void open(const filesystem::path& __p, ios_base::openmode __mode = ios_base::out)
+    { return open(__p.c_str(), __mode); }
+#endif // _LIBCPP_STD_VER >= 17
+
     _LIBCPP_INLINE_VISIBILITY
     void __open(int __fd, ios_base::openmode __mode);
 #endif
@@ -1530,6 +1577,13 @@
 #endif
     _LIBCPP_INLINE_VISIBILITY
     explicit basic_fstream(const string& __s, ios_base::openmode __mode = ios_base::in | ios_base::out);
+
+#if _LIBCPP_STD_VER >= 17
+    _LIBCPP_INLINE_VISIBILITY
+    explicit basic_fstream(const filesystem::path& __p, ios_base::openmode __mode = ios_base::in | ios_base::out)
+      : basic_fstream(__p.c_str(), __mode) {}
+#endif // _LIBCPP_STD_VER >= 17
+
 #endif
 #ifndef _LIBCPP_CXX03_LANG
     _LIBCPP_INLINE_VISIBILITY
@@ -1551,6 +1605,13 @@
     void open(const wchar_t* __s, ios_base::openmode __mode = ios_base::in | ios_base::out);
 #endif
     void open(const string& __s, ios_base::openmode __mode = ios_base::in | ios_base::out);
+
+#if _LIBCPP_STD_VER >= 17
+    _LIBCPP_INLINE_VISIBILITY
+    void open(const filesystem::path& __p, ios_base::openmode __mode = ios_base::in|ios_base::out)
+    { return open(__p.c_str(), __mode); }
+#endif // _LIBCPP_STD_VER >= 17
+
 #endif
     _LIBCPP_INLINE_VISIBILITY
     void close();
diff --git a/include/module.modulemap b/include/module.modulemap
index e17c3a2..127a42b 100644
--- a/include/module.modulemap
+++ b/include/module.modulemap
@@ -264,6 +264,10 @@
     header "exception"
     export *
   }
+  module filesystem {
+    header "filesystem"
+    export *
+  }
   module forward_list {
     header "forward_list"
     export initializer_list
diff --git a/lib/CMakeLists.txt b/lib/CMakeLists.txt
index 5cdf1b8..a40d217 100644
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@@ -291,12 +291,43 @@
 # Add a meta-target for both libraries.
 add_custom_target(cxx DEPENDS cxx-headers ${LIBCXX_BUILD_TARGETS})
 
+
+if (LIBCXX_ENABLE_FILESYSTEM)
+  set(LIBCXX_FILESYSTEM_SOURCES
+      ../src/filesystem/operations.cpp
+      ../src/filesystem/directory_iterator.cpp)
+
+  # Filesystem uses __int128_t, which requires a definition of __muloi4 when
+  # compiled with UBSAN. This definition is not provided by libgcc_s, but is
+  # provided by compiler-rt. So we need to disable it to avoid having multiple
+  # definitions. See filesystem/int128_builtins.cpp.
+  if (NOT LIBCXX_USE_COMPILER_RT)
+    list(APPEND LIBCXX_FILESYSTEM_SOURCES ../src/filesystem/int128_builtins.cpp)
+  endif()
+
+  add_library(cxx_filesystem STATIC ${LIBCXX_FILESYSTEM_SOURCES})
+  if (LIBCXX_ENABLE_SHARED)
+    target_link_libraries(cxx_filesystem cxx_shared)
+  else()
+    target_link_libraries(cxx_filesystem cxx_static)
+  endif()
+
+  set(filesystem_flags "${LIBCXX_COMPILE_FLAGS}")
+  check_flag_supported(-std=c++14)
+  if (NOT MSVC AND LIBCXX_SUPPORTS_STD_EQ_CXX14_FLAG)
+    string(REPLACE "-std=c++11" "-std=c++14" filesystem_flags "${LIBCXX_COMPILE_FLAGS}")
+  endif()
+  set_target_properties(cxx_filesystem
+    PROPERTIES
+      COMPILE_FLAGS "${filesystem_flags}"
+      OUTPUT_NAME   "c++fs"
+  )
+endif()
+
+
 if (LIBCXX_ENABLE_EXPERIMENTAL_LIBRARY)
   file(GLOB LIBCXX_EXPERIMENTAL_SOURCES ../src/experimental/*.cpp)
-  if (LIBCXX_ENABLE_FILESYSTEM)
-    file(GLOB LIBCXX_FILESYSTEM_SOURCES ../src/experimental/filesystem/*.cpp)
-  endif()
-  add_library(cxx_experimental STATIC ${LIBCXX_EXPERIMENTAL_SOURCES} ${LIBCXX_FILESYSTEM_SOURCES})
+  add_library(cxx_experimental STATIC ${LIBCXX_EXPERIMENTAL_SOURCES})
   if (LIBCXX_ENABLE_SHARED)
     target_link_libraries(cxx_experimental cxx_shared)
   else()
@@ -315,6 +346,7 @@
   )
 endif()
 
+
 if (LIBCXX_BUILD_EXTERNAL_THREAD_LIBRARY)
   file(GLOB LIBCXX_EXTERNAL_THREADING_SUPPORT_SOURCES ../test/support/external_threads.cpp)
 
@@ -362,10 +394,13 @@
 endif()
 
 if (LIBCXX_INSTALL_LIBRARY)
+  if (LIBCXX_INSTALL_FILESYSTEM_LIBRARY)
+    set(filesystem_lib cxx_filesystem)
+  endif()
   if (LIBCXX_INSTALL_EXPERIMENTAL_LIBRARY)
     set(experimental_lib cxx_experimental)
   endif()
-  install(TARGETS ${LIBCXX_INSTALL_TARGETS} ${experimental_lib}
+  install(TARGETS ${LIBCXX_INSTALL_TARGETS} ${filesystem_lib} ${experimental_lib}
     LIBRARY DESTINATION ${LIBCXX_INSTALL_PREFIX}lib${LIBCXX_LIBDIR_SUFFIX} COMPONENT cxx
     ARCHIVE DESTINATION ${LIBCXX_INSTALL_PREFIX}lib${LIBCXX_LIBDIR_SUFFIX} COMPONENT cxx
     )
@@ -385,6 +420,9 @@
     if(LIBCXX_INSTALL_LIBRARY)
       set(lib_install_target cxx)
     endif()
+    if (LIBCXX_INSTALL_FILESYSTEM_LIBRARY)
+      set(filesystem_lib_install_target cxx_filesystem)
+    endif()
     if (LIBCXX_INSTALL_EXPERIMENTAL_LIBRARY)
       set(experimental_lib_install_target cxx_experimental)
     endif()
@@ -394,6 +432,7 @@
     add_custom_target(install-cxx
                       DEPENDS ${lib_install_target}
                               ${experimental_lib_install_target}
+                              ${filesystem_lib_install_target}
                               ${header_install_target}
                       COMMAND "${CMAKE_COMMAND}"
                       -DCMAKE_INSTALL_COMPONENT=cxx
@@ -401,6 +440,7 @@
     add_custom_target(install-cxx-stripped
                       DEPENDS ${lib_install_target}
                               ${experimental_lib_install_target}
+                              ${filesystem_lib_install_target}
                               ${header_install_target}
                       COMMAND "${CMAKE_COMMAND}"
                       -DCMAKE_INSTALL_COMPONENT=cxx
diff --git a/src/experimental/filesystem/directory_iterator.cpp b/src/experimental/filesystem/directory_iterator.cpp
deleted file mode 100644
index 7a1ab25..0000000
--- a/src/experimental/filesystem/directory_iterator.cpp
+++ /dev/null
@@ -1,401 +0,0 @@
-//===------------------ directory_iterator.cpp ----------------------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is dual licensed under the MIT and the University of Illinois Open
-// Source Licenses. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-
-#include "experimental/filesystem"
-#include "__config"
-#if defined(_LIBCPP_WIN32API)
-#define WIN32_LEAN_AND_MEAN
-#include <Windows.h>
-#else
-#include <dirent.h>
-#endif
-#include <errno.h>
-
-#include "filesystem_common.h"
-
-_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL_FILESYSTEM
-
-namespace detail {
-namespace {
-
-#if !defined(_LIBCPP_WIN32API)
-template <class DirEntT, class = decltype(DirEntT::d_type)>
-static file_type get_file_type(DirEntT *ent, int) {
-  switch (ent->d_type) {
-  case DT_BLK:
-    return file_type::block;
-  case DT_CHR:
-    return file_type::character;
-  case DT_DIR:
-    return file_type::directory;
-  case DT_FIFO:
-    return file_type::fifo;
-  case DT_LNK:
-    return file_type::symlink;
-  case DT_REG:
-    return file_type::regular;
-  case DT_SOCK:
-    return file_type::socket;
-  // Unlike in lstat, hitting "unknown" here simply means that the underlying
-  // filesystem doesn't support d_type. Report is as 'none' so we correctly
-  // set the cache to empty.
-  case DT_UNKNOWN:
-    break;
-  }
-  return file_type::none;
-}
-
-template <class DirEntT>
-static file_type get_file_type(DirEntT *ent, long) {
-  return file_type::none;
-}
-
-static pair<string_view, file_type>
-posix_readdir(DIR *dir_stream,  error_code& ec) {
-    struct dirent* dir_entry_ptr = nullptr;
-    errno = 0; // zero errno in order to detect errors
-    ec.clear();
-    if ((dir_entry_ptr = ::readdir(dir_stream)) == nullptr) {
-        if (errno)
-          ec = capture_errno();
-        return {};
-    } else {
-        return {dir_entry_ptr->d_name, get_file_type(dir_entry_ptr, 0)};
-    }
-}
-#else
-
-static file_type get_file_type(const WIN32_FIND_DATA& data) {
-  //auto attrs = data.dwFileAttributes;
-  // FIXME(EricWF)
-  return file_type::unknown;
-}
-static uintmax_t get_file_size(const WIN32_FIND_DATA& data) {
-  return (data.nFileSizeHight * (MAXDWORD+1)) + data.nFileSizeLow;
-}
-static file_time_type get_write_time(const WIN32_FIND_DATA& data) {
-  ULARGE_INTEGER tmp;
-  FILETIME& time = data.ftLastWriteTime;
-  tmp.u.LowPart = time.dwLowDateTime;
-  tmp.u.HighPart = time.dwHighDateTime;
-  return file_time_type(file_time_type::duration(time.QuadPart));
-}
-
-#endif
-
-} // namespace
-} // namespace detail
-
-using detail::ErrorHandler;
-
-#if defined(_LIBCPP_WIN32API)
-class __dir_stream {
-public:
-
-  __dir_stream() = delete;
-  __dir_stream& operator=(const __dir_stream&) = delete;
-
-  __dir_stream(__dir_stream&& __ds) noexcept
-      : __stream_(__ds.__stream_), __root_(move(__ds.__root_)),
-        __entry_(move(__ds.__entry_)) {
-    __ds.__stream_ = INVALID_HANDLE_VALUE;
-  }
-
-  __dir_stream(const path& root, directory_options opts, error_code& ec)
-      : __stream_(INVALID_HANDLE_VALUE), __root_(root) {
-    __stream_ = ::FindFirstFileEx(root.c_str(),  &__data_);
-    if (__stream_ == INVALID_HANDLE_VALUE) {
-      ec = error_code(::GetLastError(), generic_category());
-      const bool ignore_permission_denied =
-          bool(opts & directory_options::skip_permission_denied);
-      if (ignore_permission_denied && ec.value() == ERROR_ACCESS_DENIED)
-        ec.clear();
-      return;
-    }
-  }
-
-  ~__dir_stream() noexcept {
-    if (__stream_ == INVALID_HANDLE_VALUE)
-      return;
-    close();
-  }
-
-  bool good() const noexcept { return __stream_ != INVALID_HANDLE_VALUE; }
-
-  bool advance(error_code& ec) {
-    while (::FindNextFile(__stream_, &__data_)) {
-      if (!strcmp(__data_.cFileName, ".") || strcmp(__data_.cFileName, ".."))
-        continue;
-      // FIXME: Cache more of this
-      //directory_entry::__cached_data cdata;
-      //cdata.__type_ = get_file_type(__data_);
-      //cdata.__size_ = get_file_size(__data_);
-      //cdata.__write_time_ = get_write_time(__data_);
-      __entry_.__assign_iter_entry(
-          __root_ / __data_.cFileName,
-          directory_entry::__create_iter_result(get_file_type(__data)));
-      return true;
-    }
-    ec = error_code(::GetLastError(), generic_category());
-    close();
-    return false;
-  }
-
-private:
-  error_code close() noexcept {
-    error_code ec;
-    if (!::FindClose(__stream_))
-      ec = error_code(::GetLastError(), generic_category());
-    __stream_ = INVALID_HANDLE_VALUE;
-    return ec;
-  }
-
-  HANDLE __stream_{INVALID_HANDLE_VALUE};
-  WIN32_FIND_DATA __data_;
-
-public:
-  path __root_;
-  directory_entry __entry_;
-};
-#else
-class __dir_stream {
-public:
-    __dir_stream() = delete;
-    __dir_stream& operator=(const __dir_stream&) = delete;
-
-    __dir_stream(__dir_stream&& other) noexcept
-        : __stream_(other.__stream_), __root_(move(other.__root_)),
-          __entry_(move(other.__entry_))
-    {
-        other.__stream_ = nullptr;
-    }
-
-
-    __dir_stream(const path& root, directory_options opts, error_code& ec)
-        : __stream_(nullptr),
-          __root_(root)
-    {
-        if ((__stream_ = ::opendir(root.c_str())) == nullptr) {
-            ec = detail::capture_errno();
-            const bool allow_eacess =
-                bool(opts & directory_options::skip_permission_denied);
-            if (allow_eacess && ec.value() == EACCES)
-                ec.clear();
-            return;
-        }
-        advance(ec);
-    }
-
-    ~__dir_stream() noexcept
-      { if (__stream_) close(); }
-
-    bool good() const noexcept { return __stream_ != nullptr; }
-
-    bool advance(error_code &ec) {
-        while (true) {
-            auto str_type_pair = detail::posix_readdir(__stream_,  ec);
-            auto& str = str_type_pair.first;
-            if (str == "." || str == "..") {
-                continue;
-            } else if (ec || str.empty()) {
-                close();
-                return false;
-            } else {
-              __entry_.__assign_iter_entry(
-                  __root_ / str,
-                  directory_entry::__create_iter_result(str_type_pair.second));
-              return true;
-            }
-        }
-    }
-private:
-    error_code close() noexcept {
-        error_code m_ec;
-        if (::closedir(__stream_) == -1)
-           m_ec = detail::capture_errno();
-        __stream_ = nullptr;
-        return m_ec;
-    }
-
-    DIR * __stream_{nullptr};
-public:
-    path __root_;
-    directory_entry __entry_;
-};
-#endif
-
-// directory_iterator
-
-directory_iterator::directory_iterator(const path& p, error_code *ec,
-                                       directory_options opts)
-{
-  ErrorHandler<void> err("directory_iterator::directory_iterator(...)", ec, &p);
-
-  error_code m_ec;
-  __imp_ = make_shared<__dir_stream>(p, opts, m_ec);
-  if (ec)
-    *ec = m_ec;
-  if (!__imp_->good()) {
-    __imp_.reset();
-    if (m_ec)
-      err.report(m_ec);
-  }
-}
-
-directory_iterator& directory_iterator::__increment(error_code *ec)
-{
-    _LIBCPP_ASSERT(__imp_, "Attempting to increment an invalid iterator");
-    ErrorHandler<void> err("directory_iterator::operator++()", ec);
-
-    error_code m_ec;
-    if (!__imp_->advance(m_ec)) {
-      path root = move(__imp_->__root_);
-      __imp_.reset();
-      if (m_ec)
-        err.report(m_ec, "at root \"%s\"", root);
-    }
-    return *this;
-
-}
-
-directory_entry const& directory_iterator::__dereference() const {
-    _LIBCPP_ASSERT(__imp_, "Attempting to dereference an invalid iterator");
-    return __imp_->__entry_;
-}
-
-// recursive_directory_iterator
-
-struct recursive_directory_iterator::__shared_imp {
-  stack<__dir_stream> __stack_;
-  directory_options   __options_;
-};
-
-recursive_directory_iterator::recursive_directory_iterator(const path& p,
-    directory_options opt, error_code *ec)
-    : __imp_(nullptr), __rec_(true)
-{
-  ErrorHandler<void> err("recursive_directory_iterator", ec, &p);
-
-  error_code m_ec;
-  __dir_stream new_s(p, opt, m_ec);
-  if (m_ec)
-    err.report(m_ec);
-  if (m_ec || !new_s.good())
-    return;
-
-  __imp_ = make_shared<__shared_imp>();
-  __imp_->__options_ = opt;
-  __imp_->__stack_.push(move(new_s));
-}
-
-void recursive_directory_iterator::__pop(error_code* ec)
-{
-    _LIBCPP_ASSERT(__imp_, "Popping the end iterator");
-    if (ec) ec->clear();
-    __imp_->__stack_.pop();
-    if (__imp_->__stack_.size() == 0)
-        __imp_.reset();
-    else
-        __advance(ec);
-}
-
-directory_options recursive_directory_iterator::options() const {
-    return __imp_->__options_;
-}
-
-int recursive_directory_iterator::depth() const {
-    return __imp_->__stack_.size() - 1;
-}
-
-const directory_entry& recursive_directory_iterator::__dereference() const {
-    return __imp_->__stack_.top().__entry_;
-}
-
-recursive_directory_iterator&
-recursive_directory_iterator::__increment(error_code *ec)
-{
-    if (ec) ec->clear();
-    if (recursion_pending()) {
-        if (__try_recursion(ec) || (ec && *ec))
-            return *this;
-    }
-    __rec_ = true;
-    __advance(ec);
-    return *this;
-}
-
-void recursive_directory_iterator::__advance(error_code* ec) {
-  ErrorHandler<void> err("recursive_directory_iterator::operator++()", ec);
-
-  const directory_iterator end_it;
-  auto& stack = __imp_->__stack_;
-  error_code m_ec;
-  while (stack.size() > 0) {
-    if (stack.top().advance(m_ec))
-      return;
-    if (m_ec)
-      break;
-    stack.pop();
-  }
-
-    if (m_ec) {
-      path root = move(stack.top().__root_);
-      __imp_.reset();
-      err.report(m_ec, "at root \"%s\"", root);
-    } else {
-      __imp_.reset();
-    }
-}
-
-bool recursive_directory_iterator::__try_recursion(error_code *ec) {
-  ErrorHandler<void> err("recursive_directory_iterator::operator++()", ec);
-
-  bool rec_sym = bool(options() & directory_options::follow_directory_symlink);
-
-  auto& curr_it = __imp_->__stack_.top();
-
-  bool skip_rec = false;
-  error_code m_ec;
-  if (!rec_sym) {
-    file_status st(curr_it.__entry_.__get_sym_ft(&m_ec));
-    if (m_ec && status_known(st))
-      m_ec.clear();
-    if (m_ec || is_symlink(st) || !is_directory(st))
-      skip_rec = true;
-  } else {
-    file_status st(curr_it.__entry_.__get_ft(&m_ec));
-    if (m_ec && status_known(st))
-      m_ec.clear();
-    if (m_ec || !is_directory(st))
-      skip_rec = true;
-  }
-
-    if (!skip_rec) {
-        __dir_stream new_it(curr_it.__entry_.path(), __imp_->__options_, m_ec);
-        if (new_it.good()) {
-            __imp_->__stack_.push(move(new_it));
-            return true;
-        }
-    }
-    if (m_ec) {
-        const bool allow_eacess = bool(__imp_->__options_
-            & directory_options::skip_permission_denied);
-        if (m_ec.value() == EACCES && allow_eacess) {
-          if (ec) ec->clear();
-        } else {
-          path at_ent = move(curr_it.__entry_.__p_);
-          __imp_.reset();
-          err.report(m_ec, "attempting recursion into \"%s\"", at_ent);
-        }
-    }
-    return false;
-}
-
-
-_LIBCPP_END_NAMESPACE_EXPERIMENTAL_FILESYSTEM
diff --git a/src/filesystem/directory_iterator.cpp b/src/filesystem/directory_iterator.cpp
new file mode 100644
index 0000000..f0d807a
--- /dev/null
+++ b/src/filesystem/directory_iterator.cpp
@@ -0,0 +1,396 @@
+//===------------------ directory_iterator.cpp ----------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "filesystem"
+#include "__config"
+#if defined(_LIBCPP_WIN32API)
+#define WIN32_LEAN_AND_MEAN
+#include <Windows.h>
+#else
+#include <dirent.h>
+#endif
+#include <errno.h>
+
+#include "filesystem_common.h"
+
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
+
+namespace detail {
+namespace {
+
+#if !defined(_LIBCPP_WIN32API)
+template <class DirEntT, class = decltype(DirEntT::d_type)>
+static file_type get_file_type(DirEntT* ent, int) {
+  switch (ent->d_type) {
+  case DT_BLK:
+    return file_type::block;
+  case DT_CHR:
+    return file_type::character;
+  case DT_DIR:
+    return file_type::directory;
+  case DT_FIFO:
+    return file_type::fifo;
+  case DT_LNK:
+    return file_type::symlink;
+  case DT_REG:
+    return file_type::regular;
+  case DT_SOCK:
+    return file_type::socket;
+  // Unlike in lstat, hitting "unknown" here simply means that the underlying
+  // filesystem doesn't support d_type. Report is as 'none' so we correctly
+  // set the cache to empty.
+  case DT_UNKNOWN:
+    break;
+  }
+  return file_type::none;
+}
+
+template <class DirEntT>
+static file_type get_file_type(DirEntT* ent, long) {
+  return file_type::none;
+}
+
+static pair<string_view, file_type> posix_readdir(DIR* dir_stream,
+                                                  error_code& ec) {
+  struct dirent* dir_entry_ptr = nullptr;
+  errno = 0; // zero errno in order to detect errors
+  ec.clear();
+  if ((dir_entry_ptr = ::readdir(dir_stream)) == nullptr) {
+    if (errno)
+      ec = capture_errno();
+    return {};
+  } else {
+    return {dir_entry_ptr->d_name, get_file_type(dir_entry_ptr, 0)};
+  }
+}
+#else
+
+static file_type get_file_type(const WIN32_FIND_DATA& data) {
+  //auto attrs = data.dwFileAttributes;
+  // FIXME(EricWF)
+  return file_type::unknown;
+}
+static uintmax_t get_file_size(const WIN32_FIND_DATA& data) {
+  return (data.nFileSizeHight * (MAXDWORD + 1)) + data.nFileSizeLow;
+}
+static file_time_type get_write_time(const WIN32_FIND_DATA& data) {
+  ULARGE_INTEGER tmp;
+  FILETIME& time = data.ftLastWriteTime;
+  tmp.u.LowPart = time.dwLowDateTime;
+  tmp.u.HighPart = time.dwHighDateTime;
+  return file_time_type(file_time_type::duration(time.QuadPart));
+}
+
+#endif
+
+} // namespace
+} // namespace detail
+
+using detail::ErrorHandler;
+
+#if defined(_LIBCPP_WIN32API)
+class __dir_stream {
+public:
+  __dir_stream() = delete;
+  __dir_stream& operator=(const __dir_stream&) = delete;
+
+  __dir_stream(__dir_stream&& __ds) noexcept : __stream_(__ds.__stream_),
+                                               __root_(move(__ds.__root_)),
+                                               __entry_(move(__ds.__entry_)) {
+    __ds.__stream_ = INVALID_HANDLE_VALUE;
+  }
+
+  __dir_stream(const path& root, directory_options opts, error_code& ec)
+      : __stream_(INVALID_HANDLE_VALUE), __root_(root) {
+    __stream_ = ::FindFirstFileEx(root.c_str(), &__data_);
+    if (__stream_ == INVALID_HANDLE_VALUE) {
+      ec = error_code(::GetLastError(), generic_category());
+      const bool ignore_permission_denied =
+          bool(opts & directory_options::skip_permission_denied);
+      if (ignore_permission_denied && ec.value() == ERROR_ACCESS_DENIED)
+        ec.clear();
+      return;
+    }
+  }
+
+  ~__dir_stream() noexcept {
+    if (__stream_ == INVALID_HANDLE_VALUE)
+      return;
+    close();
+  }
+
+  bool good() const noexcept { return __stream_ != INVALID_HANDLE_VALUE; }
+
+  bool advance(error_code& ec) {
+    while (::FindNextFile(__stream_, &__data_)) {
+      if (!strcmp(__data_.cFileName, ".") || strcmp(__data_.cFileName, ".."))
+        continue;
+      // FIXME: Cache more of this
+      //directory_entry::__cached_data cdata;
+      //cdata.__type_ = get_file_type(__data_);
+      //cdata.__size_ = get_file_size(__data_);
+      //cdata.__write_time_ = get_write_time(__data_);
+      __entry_.__assign_iter_entry(
+          __root_ / __data_.cFileName,
+          directory_entry::__create_iter_result(get_file_type(__data)));
+      return true;
+    }
+    ec = error_code(::GetLastError(), generic_category());
+    close();
+    return false;
+  }
+
+private:
+  error_code close() noexcept {
+    error_code ec;
+    if (!::FindClose(__stream_))
+      ec = error_code(::GetLastError(), generic_category());
+    __stream_ = INVALID_HANDLE_VALUE;
+    return ec;
+  }
+
+  HANDLE __stream_{INVALID_HANDLE_VALUE};
+  WIN32_FIND_DATA __data_;
+
+public:
+  path __root_;
+  directory_entry __entry_;
+};
+#else
+class __dir_stream {
+public:
+  __dir_stream() = delete;
+  __dir_stream& operator=(const __dir_stream&) = delete;
+
+  __dir_stream(__dir_stream&& other) noexcept : __stream_(other.__stream_),
+                                                __root_(move(other.__root_)),
+                                                __entry_(move(other.__entry_)) {
+    other.__stream_ = nullptr;
+  }
+
+  __dir_stream(const path& root, directory_options opts, error_code& ec)
+      : __stream_(nullptr), __root_(root) {
+    if ((__stream_ = ::opendir(root.c_str())) == nullptr) {
+      ec = detail::capture_errno();
+      const bool allow_eacess =
+          bool(opts & directory_options::skip_permission_denied);
+      if (allow_eacess && ec.value() == EACCES)
+        ec.clear();
+      return;
+    }
+    advance(ec);
+  }
+
+  ~__dir_stream() noexcept {
+    if (__stream_)
+      close();
+  }
+
+  bool good() const noexcept { return __stream_ != nullptr; }
+
+  bool advance(error_code& ec) {
+    while (true) {
+      auto str_type_pair = detail::posix_readdir(__stream_, ec);
+      auto& str = str_type_pair.first;
+      if (str == "." || str == "..") {
+        continue;
+      } else if (ec || str.empty()) {
+        close();
+        return false;
+      } else {
+        __entry_.__assign_iter_entry(
+            __root_ / str,
+            directory_entry::__create_iter_result(str_type_pair.second));
+        return true;
+      }
+    }
+  }
+
+private:
+  error_code close() noexcept {
+    error_code m_ec;
+    if (::closedir(__stream_) == -1)
+      m_ec = detail::capture_errno();
+    __stream_ = nullptr;
+    return m_ec;
+  }
+
+  DIR* __stream_{nullptr};
+
+public:
+  path __root_;
+  directory_entry __entry_;
+};
+#endif
+
+// directory_iterator
+
+directory_iterator::directory_iterator(const path& p, error_code* ec,
+                                       directory_options opts) {
+  ErrorHandler<void> err("directory_iterator::directory_iterator(...)", ec, &p);
+
+  error_code m_ec;
+  __imp_ = make_shared<__dir_stream>(p, opts, m_ec);
+  if (ec)
+    *ec = m_ec;
+  if (!__imp_->good()) {
+    __imp_.reset();
+    if (m_ec)
+      err.report(m_ec);
+  }
+}
+
+directory_iterator& directory_iterator::__increment(error_code* ec) {
+  _LIBCPP_ASSERT(__imp_, "Attempting to increment an invalid iterator");
+  ErrorHandler<void> err("directory_iterator::operator++()", ec);
+
+  error_code m_ec;
+  if (!__imp_->advance(m_ec)) {
+    path root = move(__imp_->__root_);
+    __imp_.reset();
+    if (m_ec)
+      err.report(m_ec, "at root \"%s\"", root);
+  }
+  return *this;
+}
+
+directory_entry const& directory_iterator::__dereference() const {
+  _LIBCPP_ASSERT(__imp_, "Attempting to dereference an invalid iterator");
+  return __imp_->__entry_;
+}
+
+// recursive_directory_iterator
+
+struct recursive_directory_iterator::__shared_imp {
+  stack<__dir_stream> __stack_;
+  directory_options __options_;
+};
+
+recursive_directory_iterator::recursive_directory_iterator(
+    const path& p, directory_options opt, error_code* ec)
+    : __imp_(nullptr), __rec_(true) {
+  ErrorHandler<void> err("recursive_directory_iterator", ec, &p);
+
+  error_code m_ec;
+  __dir_stream new_s(p, opt, m_ec);
+  if (m_ec)
+    err.report(m_ec);
+  if (m_ec || !new_s.good())
+    return;
+
+  __imp_ = make_shared<__shared_imp>();
+  __imp_->__options_ = opt;
+  __imp_->__stack_.push(move(new_s));
+}
+
+void recursive_directory_iterator::__pop(error_code* ec) {
+  _LIBCPP_ASSERT(__imp_, "Popping the end iterator");
+  if (ec)
+    ec->clear();
+  __imp_->__stack_.pop();
+  if (__imp_->__stack_.size() == 0)
+    __imp_.reset();
+  else
+    __advance(ec);
+}
+
+directory_options recursive_directory_iterator::options() const {
+  return __imp_->__options_;
+}
+
+int recursive_directory_iterator::depth() const {
+  return __imp_->__stack_.size() - 1;
+}
+
+const directory_entry& recursive_directory_iterator::__dereference() const {
+  return __imp_->__stack_.top().__entry_;
+}
+
+recursive_directory_iterator&
+recursive_directory_iterator::__increment(error_code* ec) {
+  if (ec)
+    ec->clear();
+  if (recursion_pending()) {
+    if (__try_recursion(ec) || (ec && *ec))
+      return *this;
+  }
+  __rec_ = true;
+  __advance(ec);
+  return *this;
+}
+
+void recursive_directory_iterator::__advance(error_code* ec) {
+  ErrorHandler<void> err("recursive_directory_iterator::operator++()", ec);
+
+  const directory_iterator end_it;
+  auto& stack = __imp_->__stack_;
+  error_code m_ec;
+  while (stack.size() > 0) {
+    if (stack.top().advance(m_ec))
+      return;
+    if (m_ec)
+      break;
+    stack.pop();
+  }
+
+  if (m_ec) {
+    path root = move(stack.top().__root_);
+    __imp_.reset();
+    err.report(m_ec, "at root \"%s\"", root);
+  } else {
+    __imp_.reset();
+  }
+}
+
+bool recursive_directory_iterator::__try_recursion(error_code* ec) {
+  ErrorHandler<void> err("recursive_directory_iterator::operator++()", ec);
+
+  bool rec_sym = bool(options() & directory_options::follow_directory_symlink);
+
+  auto& curr_it = __imp_->__stack_.top();
+
+  bool skip_rec = false;
+  error_code m_ec;
+  if (!rec_sym) {
+    file_status st(curr_it.__entry_.__get_sym_ft(&m_ec));
+    if (m_ec && status_known(st))
+      m_ec.clear();
+    if (m_ec || is_symlink(st) || !is_directory(st))
+      skip_rec = true;
+  } else {
+    file_status st(curr_it.__entry_.__get_ft(&m_ec));
+    if (m_ec && status_known(st))
+      m_ec.clear();
+    if (m_ec || !is_directory(st))
+      skip_rec = true;
+  }
+
+  if (!skip_rec) {
+    __dir_stream new_it(curr_it.__entry_.path(), __imp_->__options_, m_ec);
+    if (new_it.good()) {
+      __imp_->__stack_.push(move(new_it));
+      return true;
+    }
+  }
+  if (m_ec) {
+    const bool allow_eacess =
+        bool(__imp_->__options_ & directory_options::skip_permission_denied);
+    if (m_ec.value() == EACCES && allow_eacess) {
+      if (ec)
+        ec->clear();
+    } else {
+      path at_ent = move(curr_it.__entry_.__p_);
+      __imp_.reset();
+      err.report(m_ec, "attempting recursion into \"%s\"", at_ent);
+    }
+  }
+  return false;
+}
+
+_LIBCPP_END_NAMESPACE_FILESYSTEM
diff --git a/src/experimental/filesystem/filesystem_common.h b/src/filesystem/filesystem_common.h
similarity index 95%
rename from src/experimental/filesystem/filesystem_common.h
rename to src/filesystem/filesystem_common.h
index 94f4d41..ed92877 100644
--- a/src/experimental/filesystem/filesystem_common.h
+++ b/src/filesystem/filesystem_common.h
@@ -10,7 +10,8 @@
 #ifndef FILESYSTEM_COMMON_H
 #define FILESYSTEM_COMMON_H
 
-#include "experimental/__config"
+#include "__config"
+#include "filesystem"
 #include "array"
 #include "chrono"
 #include "cstdlib"
@@ -20,11 +21,9 @@
 #include <sys/stat.h>
 #include <sys/statvfs.h>
 #include <sys/time.h> // for ::utimes as used in __last_write_time
-#include <fcntl.h> /* values for fchmodat */
+#include <fcntl.h>    /* values for fchmodat */
 
-#include <experimental/filesystem>
-
-#include "../../include/apple_availability.h"
+#include "../include/apple_availability.h"
 
 #if !defined(__APPLE__)
 // We can use the presence of UTIME_OMIT to detect platforms that provide
@@ -39,7 +38,7 @@
 #pragma GCC diagnostic ignored "-Wunused-function"
 #endif
 
-_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL_FILESYSTEM
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
 
 namespace detail {
 namespace {
@@ -49,7 +48,7 @@
   struct GuardVAList {
     va_list& target;
     bool active = true;
-    GuardVAList(va_list &target) : target(target), active(true) {}
+    GuardVAList(va_list& target) : target(target), active(true) {}
     void clear() {
       if (active)
         va_end(target);
@@ -386,10 +385,10 @@
 // to use it.
 
 bool posix_utimes(const path& p, std::array<TimeSpec, 2> const& TS,
-                    error_code& ec) {
+                  error_code& ec) {
   using namespace chrono;
   auto Convert = [](long nsec) {
-    using int_type = decltype(std::declval<::timeval>().tv_usec);
+    using int_type = decltype(std::declval< ::timeval>().tv_usec);
     auto dur = duration_cast<microseconds>(nanoseconds(nsec)).count();
     return static_cast<int_type>(dur);
   };
@@ -404,9 +403,8 @@
 
 #if defined(_LIBCPP_USE_UTIMENSAT)
 bool posix_utimensat(const path& p, std::array<TimeSpec, 2> const& TS,
-                    error_code& ec) {
-  if (::utimensat(AT_FDCWD, p.c_str(), TS.data(), 0) == -1)
-  {
+                     error_code& ec) {
+  if (::utimensat(AT_FDCWD, p.c_str(), TS.data(), 0) == -1) {
     ec = capture_errno();
     return true;
   }
@@ -423,10 +421,9 @@
 #endif
 }
 
-
 } // namespace
 } // end namespace detail
 
-_LIBCPP_END_NAMESPACE_EXPERIMENTAL_FILESYSTEM
+_LIBCPP_END_NAMESPACE_FILESYSTEM
 
 #endif // FILESYSTEM_COMMON_H
diff --git a/src/experimental/filesystem/int128_builtins.cpp b/src/filesystem/int128_builtins.cpp
similarity index 97%
rename from src/experimental/filesystem/int128_builtins.cpp
rename to src/filesystem/int128_builtins.cpp
index d8f2abb..66adbdd 100644
--- a/src/experimental/filesystem/int128_builtins.cpp
+++ b/src/filesystem/int128_builtins.cpp
@@ -17,7 +17,7 @@
 #include "__config"
 #include "climits"
 
-#ifndef _LIBCPP_HAS_NO_INT128
+#if !defined(_LIBCPP_HAS_NO_INT128)
 
 extern "C" __attribute__((no_sanitize("undefined")))
 __int128_t __muloti4(__int128_t a, __int128_t b, int* overflow) {
diff --git a/src/experimental/filesystem/operations.cpp b/src/filesystem/operations.cpp
similarity index 76%
rename from src/experimental/filesystem/operations.cpp
rename to src/filesystem/operations.cpp
index 775c178..65a4b31 100644
--- a/src/experimental/filesystem/operations.cpp
+++ b/src/filesystem/operations.cpp
@@ -7,11 +7,11 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "experimental/filesystem"
+#include "filesystem"
 #include "array"
 #include "iterator"
 #include "fstream"
-#include "random"  /* for unique_path */
+#include "random" /* for unique_path */
 #include "string_view"
 #include "type_traits"
 #include "vector"
@@ -24,17 +24,17 @@
 #include <sys/stat.h>
 #include <sys/statvfs.h>
 #include <time.h>
-#include <fcntl.h>  /* values for fchmodat */
+#include <fcntl.h> /* values for fchmodat */
 
 #if defined(__linux__)
-# include <linux/version.h>
-# if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 33)
-#   include <sys/sendfile.h>
-#   define _LIBCPP_USE_SENDFILE
-# endif
+#include <linux/version.h>
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 33)
+#include <sys/sendfile.h>
+#define _LIBCPP_USE_SENDFILE
+#endif
 #elif defined(__APPLE__) || __has_include(<copyfile.h>)
 #include <copyfile.h>
-# define _LIBCPP_USE_COPYFILE
+#define _LIBCPP_USE_COPYFILE
 #endif
 
 #if !defined(__APPLE__)
@@ -51,10 +51,10 @@
 #endif
 #endif
 
-_LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL_FILESYSTEM
+_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
 
-namespace { namespace parser
-{
+namespace {
+namespace parser {
 
 using string_view_t = path::__string_view;
 using string_view_pair = pair<string_view_t, string_view_t>;
@@ -76,8 +76,8 @@
   ParserState State;
 
 private:
-  PathParser(string_view_t P, ParserState State) noexcept
-      : Path(P), State(State) {}
+  PathParser(string_view_t P, ParserState State) noexcept : Path(P),
+                                                            State(State) {}
 
 public:
   PathParser(string_view_t P, string_view_t E, unsigned char S)
@@ -157,7 +157,8 @@
       }
     }
     case PS_InTrailingSep:
-      return makeState(PS_InFilenames, consumeName(RStart, REnd) + 1, RStart + 1);
+      return makeState(PS_InFilenames, consumeName(RStart, REnd) + 1,
+                       RStart + 1);
     case PS_InFilenames: {
       PosPtr SepEnd = consumeSeparator(RStart, REnd);
       if (SepEnd == REnd)
@@ -219,13 +220,9 @@
     RawEntry = {};
   }
 
-  PosPtr getAfterBack() const noexcept {
-    return Path.data() + Path.size();
-  }
+  PosPtr getAfterBack() const noexcept { return Path.data() + Path.size(); }
 
-  PosPtr getBeforeFront() const noexcept {
-    return Path.data() - 1;
-  }
+  PosPtr getBeforeFront() const noexcept { return Path.data() - 1; }
 
   /// \brief Return a pointer to the first character after the currently
   ///   lexed element.
@@ -282,24 +279,26 @@
   }
 };
 
-string_view_pair separate_filename(string_view_t const & s) {
-    if (s == "." || s == ".." || s.empty()) return string_view_pair{s, ""};
-    auto pos = s.find_last_of('.');
-    if (pos == string_view_t::npos || pos == 0)
-        return string_view_pair{s, string_view_t{}};
-    return string_view_pair{s.substr(0, pos), s.substr(pos)};
+string_view_pair separate_filename(string_view_t const& s) {
+  if (s == "." || s == ".." || s.empty())
+    return string_view_pair{s, ""};
+  auto pos = s.find_last_of('.');
+  if (pos == string_view_t::npos || pos == 0)
+    return string_view_pair{s, string_view_t{}};
+  return string_view_pair{s.substr(0, pos), s.substr(pos)};
 }
 
 string_view_t createView(PosPtr S, PosPtr E) noexcept {
   return {S, static_cast<size_t>(E - S) + 1};
 }
 
-}} // namespace parser
-
+} // namespace parser
+} // namespace
 
 //                       POSIX HELPERS
 
-namespace detail { namespace  {
+namespace detail {
+namespace {
 
 using value_type = path::value_type;
 using string_type = path::string_type;
@@ -429,8 +428,7 @@
   return posix_lstat(p, path_stat, ec);
 }
 
-bool posix_ftruncate(const FileDescriptor& fd, size_t to_size,
-                     error_code& ec) {
+bool posix_ftruncate(const FileDescriptor& fd, size_t to_size, error_code& ec) {
   if (::ftruncate(fd.fd, to_size) == -1) {
     ec = capture_errno();
     return true;
@@ -462,7 +460,8 @@
   m_status = create_file_status(m_ec, name, m_stat, &ec);
   return m_status;
 }
-}} // end namespace detail
+} // namespace
+} // end namespace detail
 
 using detail::capture_errno;
 using detail::ErrorHandler;
@@ -511,37 +510,36 @@
   }();
 }
 
-static path __do_absolute(const path& p, path *cwd, error_code *ec) {
-  if (ec) ec->clear();
-    if (p.is_absolute())
-      return p;
-    *cwd = __current_path(ec);
-    if (ec && *ec)
-      return {};
-    return (*cwd) / p;
+static path __do_absolute(const path& p, path* cwd, error_code* ec) {
+  if (ec)
+    ec->clear();
+  if (p.is_absolute())
+    return p;
+  *cwd = __current_path(ec);
+  if (ec && *ec)
+    return {};
+  return (*cwd) / p;
 }
 
-path __absolute(const path& p, error_code *ec) {
-    path cwd;
-    return __do_absolute(p, &cwd, ec);
+path __absolute(const path& p, error_code* ec) {
+  path cwd;
+  return __do_absolute(p, &cwd, ec);
 }
 
-path __canonical(path const & orig_p, error_code *ec)
-{
-    path cwd;
-    ErrorHandler<path> err("canonical", ec, &orig_p, &cwd);
+path __canonical(path const& orig_p, error_code* ec) {
+  path cwd;
+  ErrorHandler<path> err("canonical", ec, &orig_p, &cwd);
 
-    path p = __do_absolute(orig_p, &cwd, ec);
-    char buff[PATH_MAX + 1];
-    char *ret;
-    if ((ret = ::realpath(p.c_str(), buff)) == nullptr)
-      return err.report(capture_errno());
-    return {ret};
+  path p = __do_absolute(orig_p, &cwd, ec);
+  char buff[PATH_MAX + 1];
+  char* ret;
+  if ((ret = ::realpath(p.c_str(), buff)) == nullptr)
+    return err.report(capture_errno());
+  return {ret};
 }
 
 void __copy(const path& from, const path& to, copy_options options,
-            error_code *ec)
-{
+            error_code* ec) {
   ErrorHandler<void> err("copy", ec, &from, &to);
 
   const bool sym_status = bool(
@@ -570,65 +568,65 @@
     return err.report(errc::function_not_supported);
   }
 
-    if (ec) ec->clear();
+  if (ec)
+    ec->clear();
 
-    if (is_symlink(f)) {
-        if (bool(copy_options::skip_symlinks & options)) {
-            // do nothing
-        } else if (not exists(t)) {
-            __copy_symlink(from, to, ec);
-        } else {
-          return err.report(errc::file_exists);
-        }
-        return;
+  if (is_symlink(f)) {
+    if (bool(copy_options::skip_symlinks & options)) {
+      // do nothing
+    } else if (not exists(t)) {
+      __copy_symlink(from, to, ec);
+    } else {
+      return err.report(errc::file_exists);
     }
-    else if (is_regular_file(f)) {
-        if (bool(copy_options::directories_only & options)) {
-            // do nothing
-        }
-        else if (bool(copy_options::create_symlinks & options)) {
-            __create_symlink(from, to, ec);
-        }
-        else if (bool(copy_options::create_hard_links & options)) {
-            __create_hard_link(from, to, ec);
-        }
-        else if (is_directory(t)) {
-            __copy_file(from, to / from.filename(), options, ec);
-        } else {
-            __copy_file(from, to, options, ec);
-        }
-        return;
+    return;
+  } else if (is_regular_file(f)) {
+    if (bool(copy_options::directories_only & options)) {
+      // do nothing
+    } else if (bool(copy_options::create_symlinks & options)) {
+      __create_symlink(from, to, ec);
+    } else if (bool(copy_options::create_hard_links & options)) {
+      __create_hard_link(from, to, ec);
+    } else if (is_directory(t)) {
+      __copy_file(from, to / from.filename(), options, ec);
+    } else {
+      __copy_file(from, to, options, ec);
     }
-    else if (is_directory(f) && bool(copy_options::create_symlinks & options)) {
-      return err.report(errc::is_a_directory);
-    }
-    else if (is_directory(f) && (bool(copy_options::recursive & options) ||
-             copy_options::none == options)) {
+    return;
+  } else if (is_directory(f) && bool(copy_options::create_symlinks & options)) {
+    return err.report(errc::is_a_directory);
+  } else if (is_directory(f) && (bool(copy_options::recursive & options) ||
+                                 copy_options::none == options)) {
 
-        if (!exists(t)) {
-            // create directory to with attributes from 'from'.
-            __create_directory(to, from, ec);
-            if (ec && *ec) { return; }
-        }
-        directory_iterator it = ec ? directory_iterator(from, *ec)
-                                   : directory_iterator(from);
-        if (ec && *ec) { return; }
-        error_code m_ec2;
-        for (; it != directory_iterator(); it.increment(m_ec2)) {
-          if (m_ec2) {
-            return err.report(m_ec2);
-          }
-            __copy(it->path(), to / it->path().filename(),
-                   options | copy_options::__in_recursive_copy, ec);
-            if (ec && *ec) { return; }
-        }
+    if (!exists(t)) {
+      // create directory to with attributes from 'from'.
+      __create_directory(to, from, ec);
+      if (ec && *ec) {
+        return;
+      }
     }
+    directory_iterator it =
+        ec ? directory_iterator(from, *ec) : directory_iterator(from);
+    if (ec && *ec) {
+      return;
+    }
+    error_code m_ec2;
+    for (; it != directory_iterator(); it.increment(m_ec2)) {
+      if (m_ec2) {
+        return err.report(m_ec2);
+      }
+      __copy(it->path(), to / it->path().filename(),
+             options | copy_options::__in_recursive_copy, ec);
+      if (ec && *ec) {
+        return;
+      }
+    }
+  }
 }
 
 namespace detail {
 namespace {
 
-
 #ifdef _LIBCPP_USE_SENDFILE
 bool copy_file_impl_sendfile(FileDescriptor& read_fd, FileDescriptor& write_fd,
                              error_code& ec) {
@@ -721,8 +719,7 @@
 } // namespace detail
 
 bool __copy_file(const path& from, const path& to, copy_options options,
-                 error_code *ec)
-{
+                 error_code* ec) {
   using detail::FileDescriptor;
   ErrorHandler<bool> err("copy_file", ec, &to, &from);
 
@@ -811,18 +808,18 @@
 }
 
 void __copy_symlink(const path& existing_symlink, const path& new_symlink,
-                    error_code *ec)
-{
-    const path real_path(__read_symlink(existing_symlink, ec));
-    if (ec && *ec) { return; }
-    // NOTE: proposal says you should detect if you should call
-    // create_symlink or create_directory_symlink. I don't think this
-    // is needed with POSIX
-    __create_symlink(real_path, new_symlink, ec);
+                    error_code* ec) {
+  const path real_path(__read_symlink(existing_symlink, ec));
+  if (ec && *ec) {
+    return;
+  }
+  // NOTE: proposal says you should detect if you should call
+  // create_symlink or create_directory_symlink. I don't think this
+  // is needed with POSIX
+  __create_symlink(real_path, new_symlink, ec);
 }
 
-bool __create_directories(const path& p, error_code *ec)
-{
+bool __create_directories(const path& p, error_code* ec) {
   ErrorHandler<bool> err("create_directories", ec, &p);
 
   error_code m_ec;
@@ -846,11 +843,10 @@
       }
     }
   }
-    return __create_directory(p, ec);
+  return __create_directory(p, ec);
 }
 
-bool __create_directory(const path& p, error_code *ec)
-{
+bool __create_directory(const path& p, error_code* ec) {
   ErrorHandler<bool> err("create_directory", ec, &p);
 
   if (::mkdir(p.c_str(), static_cast<int>(perms::all)) == 0)
@@ -860,9 +856,7 @@
   return false;
 }
 
-bool __create_directory(path const & p, path const & attributes,
-                        error_code *ec)
-{
+bool __create_directory(path const& p, path const& attributes, error_code* ec) {
   ErrorHandler<bool> err("create_directory", ec, &p, &attributes);
 
   StatT attr_stat;
@@ -871,7 +865,8 @@
   if (!status_known(st))
     return err.report(mec);
   if (!is_directory(st))
-    return err.report(errc::not_a_directory, "the specified attribute path is invalid");
+    return err.report(errc::not_a_directory,
+                      "the specified attribute path is invalid");
 
   if (::mkdir(p.c_str(), attr_stat.st_mode) == 0)
     return true;
@@ -887,19 +882,19 @@
     return err.report(capture_errno());
 }
 
-void __create_hard_link(const path& from, const path& to, error_code *ec){
+void __create_hard_link(const path& from, const path& to, error_code* ec) {
   ErrorHandler<void> err("create_hard_link", ec, &from, &to);
   if (::link(from.c_str(), to.c_str()) == -1)
     return err.report(capture_errno());
 }
 
-void __create_symlink(path const & from, path const & to, error_code *ec) {
+void __create_symlink(path const& from, path const& to, error_code* ec) {
   ErrorHandler<void> err("create_symlink", ec, &from, &to);
   if (::symlink(from.c_str(), to.c_str()) == -1)
     return err.report(capture_errno());
 }
 
-path __current_path(error_code *ec) {
+path __current_path(error_code* ec) {
   ErrorHandler<path> err("current_path", ec);
 
   auto size = ::pathconf(".", _PC_PATH_MAX);
@@ -913,14 +908,13 @@
   return {buff.get()};
 }
 
-void __current_path(const path& p, error_code *ec) {
+void __current_path(const path& p, error_code* ec) {
   ErrorHandler<void> err("current_path", ec, &p);
   if (::chdir(p.c_str()) == -1)
     err.report(capture_errno());
 }
 
-bool __equivalent(const path& p1, const path& p2, error_code *ec)
-{
+bool __equivalent(const path& p1, const path& p2, error_code* ec) {
   ErrorHandler<bool> err("equivalent", ec, &p1, &p2);
 
   error_code ec1, ec2;
@@ -935,9 +929,7 @@
   return detail::stat_equivalent(st1, st2);
 }
 
-
-uintmax_t __file_size(const path& p, error_code *ec)
-{
+uintmax_t __file_size(const path& p, error_code* ec) {
   ErrorHandler<uintmax_t> err("file_size", ec, &p);
 
   error_code m_ec;
@@ -950,12 +942,11 @@
       m_ec = make_error_code(error_kind);
     return err.report(m_ec);
   }
-    // is_regular_file(p) == true
-    return static_cast<uintmax_t>(st.st_size);
+  // is_regular_file(p) == true
+  return static_cast<uintmax_t>(st.st_size);
 }
 
-uintmax_t __hard_link_count(const path& p, error_code *ec)
-{
+uintmax_t __hard_link_count(const path& p, error_code* ec) {
   ErrorHandler<uintmax_t> err("hard_link_count", ec, &p);
 
   error_code m_ec;
@@ -966,9 +957,7 @@
   return static_cast<uintmax_t>(st.st_nlink);
 }
 
-
-bool __fs_is_empty(const path& p, error_code *ec)
-{
+bool __fs_is_empty(const path& p, error_code* ec) {
   ErrorHandler<bool> err("is_empty", ec, &p);
 
   error_code m_ec;
@@ -1001,52 +990,47 @@
   return fs_time::convert_from_timespec(ts);
 }
 
-file_time_type __last_write_time(const path& p, error_code *ec)
-{
-    using namespace chrono;
-    ErrorHandler<file_time_type> err("last_write_time", ec, &p);
+file_time_type __last_write_time(const path& p, error_code* ec) {
+  using namespace chrono;
+  ErrorHandler<file_time_type> err("last_write_time", ec, &p);
 
-    error_code m_ec;
-    StatT st;
-    detail::posix_stat(p, st, &m_ec);
-    if (m_ec)
-      return err.report(m_ec);
-    return __extract_last_write_time(p, st, ec);
+  error_code m_ec;
+  StatT st;
+  detail::posix_stat(p, st, &m_ec);
+  if (m_ec)
+    return err.report(m_ec);
+  return __extract_last_write_time(p, st, ec);
 }
 
-void __last_write_time(const path& p, file_time_type new_time,
-                       error_code *ec)
-{
-    using detail::fs_time;
-    ErrorHandler<void> err("last_write_time", ec, &p);
+void __last_write_time(const path& p, file_time_type new_time, error_code* ec) {
+  using detail::fs_time;
+  ErrorHandler<void> err("last_write_time", ec, &p);
 
-    error_code m_ec;
-    array<TimeSpec, 2> tbuf;
+  error_code m_ec;
+  array<TimeSpec, 2> tbuf;
 #if !defined(_LIBCPP_USE_UTIMENSAT)
-    // This implementation has a race condition between determining the
-    // last access time and attempting to set it to the same value using
-    // ::utimes
-    StatT st;
-    file_status fst = detail::posix_stat(p, st, &m_ec);
-    if (m_ec)
-      return err.report(m_ec);
-    tbuf[0] = detail::extract_atime(st);
+  // This implementation has a race condition between determining the
+  // last access time and attempting to set it to the same value using
+  // ::utimes
+  StatT st;
+  file_status fst = detail::posix_stat(p, st, &m_ec);
+  if (m_ec)
+    return err.report(m_ec);
+  tbuf[0] = detail::extract_atime(st);
 #else
-    tbuf[0].tv_sec = 0;
-    tbuf[0].tv_nsec = UTIME_OMIT;
+  tbuf[0].tv_sec = 0;
+  tbuf[0].tv_nsec = UTIME_OMIT;
 #endif
-    if (!fs_time::convert_to_timespec(tbuf[1], new_time))
-      return err.report(errc::value_too_large);
+  if (!fs_time::convert_to_timespec(tbuf[1], new_time))
+    return err.report(errc::value_too_large);
 
-    detail::set_file_times(p, tbuf, m_ec);
-    if (m_ec)
-      return err.report(m_ec);
+  detail::set_file_times(p, tbuf, m_ec);
+  if (m_ec)
+    return err.report(m_ec);
 }
 
-
 void __permissions(const path& p, perms prms, perm_options opts,
-                   error_code *ec)
-{
+                   error_code* ec) {
   ErrorHandler<void> err("permissions", ec, &p);
 
   auto has_opt = [&](perm_options o) { return bool(o & opts); };
@@ -1074,24 +1058,23 @@
     else if (remove_perms)
       prms = st.permissions() & ~prms;
   }
-    const auto real_perms = detail::posix_convert_perms(prms);
+  const auto real_perms = detail::posix_convert_perms(prms);
 
-# if defined(AT_SYMLINK_NOFOLLOW) && defined(AT_FDCWD)
-    const int flags = set_sym_perms ? AT_SYMLINK_NOFOLLOW : 0;
-    if (::fchmodat(AT_FDCWD, p.c_str(), real_perms, flags) == -1) {
-      return err.report(capture_errno());
-    }
-# else
-    if (set_sym_perms)
-      return err.report(errc::operation_not_supported);
-    if (::chmod(p.c_str(), real_perms) == -1) {
-      return err.report(capture_errno());
-    }
-# endif
+#if defined(AT_SYMLINK_NOFOLLOW) && defined(AT_FDCWD)
+  const int flags = set_sym_perms ? AT_SYMLINK_NOFOLLOW : 0;
+  if (::fchmodat(AT_FDCWD, p.c_str(), real_perms, flags) == -1) {
+    return err.report(capture_errno());
+  }
+#else
+  if (set_sym_perms)
+    return err.report(errc::operation_not_supported);
+  if (::chmod(p.c_str(), real_perms) == -1) {
+    return err.report(capture_errno());
+  }
+#endif
 }
 
-
-path __read_symlink(const path& p, error_code *ec) {
+path __read_symlink(const path& p, error_code* ec) {
   ErrorHandler<path> err("read_symlink", ec, &p);
 
   char buff[PATH_MAX + 1];
@@ -1100,47 +1083,49 @@
   if ((ret = ::readlink(p.c_str(), buff, PATH_MAX)) == -1) {
     return err.report(capture_errno());
   }
-    _LIBCPP_ASSERT(ret <= PATH_MAX, "TODO");
-    _LIBCPP_ASSERT(ret > 0, "TODO");
-    buff[ret] = 0;
-    return {buff};
+  _LIBCPP_ASSERT(ret <= PATH_MAX, "TODO");
+  _LIBCPP_ASSERT(ret > 0, "TODO");
+  buff[ret] = 0;
+  return {buff};
 }
 
-
-bool __remove(const path& p, error_code *ec) {
+bool __remove(const path& p, error_code* ec) {
   ErrorHandler<bool> err("remove", ec, &p);
   if (::remove(p.c_str()) == -1) {
     if (errno != ENOENT)
       err.report(capture_errno());
     return false;
   }
-    return true;
+  return true;
 }
 
 namespace {
 
-uintmax_t remove_all_impl(path const & p, error_code& ec)
-{
-    const auto npos = static_cast<uintmax_t>(-1);
-    const file_status st = __symlink_status(p, &ec);
-    if (ec) return npos;
-     uintmax_t count = 1;
-    if (is_directory(st)) {
-        for (directory_iterator it(p, ec); !ec && it != directory_iterator();
-             it.increment(ec)) {
-            auto other_count = remove_all_impl(it->path(), ec);
-            if (ec) return npos;
-            count += other_count;
-        }
-        if (ec) return npos;
+uintmax_t remove_all_impl(path const& p, error_code& ec) {
+  const auto npos = static_cast<uintmax_t>(-1);
+  const file_status st = __symlink_status(p, &ec);
+  if (ec)
+    return npos;
+  uintmax_t count = 1;
+  if (is_directory(st)) {
+    for (directory_iterator it(p, ec); !ec && it != directory_iterator();
+         it.increment(ec)) {
+      auto other_count = remove_all_impl(it->path(), ec);
+      if (ec)
+        return npos;
+      count += other_count;
     }
-    if (!__remove(p, &ec)) return npos;
-    return count;
+    if (ec)
+      return npos;
+  }
+  if (!__remove(p, &ec))
+    return npos;
+  return count;
 }
 
 } // end namespace
 
-uintmax_t __remove_all(const path& p, error_code *ec) {
+uintmax_t __remove_all(const path& p, error_code* ec) {
   ErrorHandler<uintmax_t> err("remove_all", ec, &p);
 
   error_code mec;
@@ -1150,22 +1135,22 @@
       return 0;
     return err.report(mec);
   }
-    return count;
+  return count;
 }
 
-void __rename(const path& from, const path& to, error_code *ec) {
+void __rename(const path& from, const path& to, error_code* ec) {
   ErrorHandler<void> err("rename", ec, &from, &to);
   if (::rename(from.c_str(), to.c_str()) == -1)
     err.report(capture_errno());
 }
 
-void __resize_file(const path& p, uintmax_t size, error_code *ec) {
+void __resize_file(const path& p, uintmax_t size, error_code* ec) {
   ErrorHandler<void> err("resize_file", ec, &p);
   if (::truncate(p.c_str(), static_cast< ::off_t>(size)) == -1)
     return err.report(capture_errno());
 }
 
-space_info __space(const path& p, error_code *ec) {
+space_info __space(const path& p, error_code* ec) {
   ErrorHandler<void> err("space", ec, &p);
   space_info si;
   struct statvfs m_svfs = {};
@@ -1174,24 +1159,24 @@
     si.capacity = si.free = si.available = static_cast<uintmax_t>(-1);
     return si;
   }
-    // Multiply with overflow checking.
-    auto do_mult = [&](uintmax_t& out, uintmax_t other) {
-      out = other * m_svfs.f_frsize;
-      if (other == 0 || out / other != m_svfs.f_frsize)
-          out = static_cast<uintmax_t>(-1);
-    };
-    do_mult(si.capacity, m_svfs.f_blocks);
-    do_mult(si.free, m_svfs.f_bfree);
-    do_mult(si.available, m_svfs.f_bavail);
-    return si;
+  // Multiply with overflow checking.
+  auto do_mult = [&](uintmax_t& out, uintmax_t other) {
+    out = other * m_svfs.f_frsize;
+    if (other == 0 || out / other != m_svfs.f_frsize)
+      out = static_cast<uintmax_t>(-1);
+  };
+  do_mult(si.capacity, m_svfs.f_blocks);
+  do_mult(si.free, m_svfs.f_bfree);
+  do_mult(si.available, m_svfs.f_bavail);
+  return si;
 }
 
-file_status __status(const path& p, error_code *ec) {
-    return detail::posix_stat(p, ec);
+file_status __status(const path& p, error_code* ec) {
+  return detail::posix_stat(p, ec);
 }
 
-file_status __symlink_status(const path& p, error_code *ec) {
-    return detail::posix_lstat(p, ec);
+file_status __symlink_status(const path& p, error_code* ec) {
+  return detail::posix_lstat(p, ec);
 }
 
 path __temp_directory_path(error_code* ec) {
@@ -1219,8 +1204,7 @@
   return p;
 }
 
-
-path __weakly_canonical(const path& p, error_code *ec) {
+path __weakly_canonical(const path& p, error_code* ec) {
   ErrorHandler<path> err("weakly_canonical", ec, &p);
 
   if (p.empty())
@@ -1248,10 +1232,11 @@
   }
   if (PP.State == PathParser::PS_BeforeBegin)
     result = __canonical("", ec);
-  if (ec) ec->clear();
+  if (ec)
+    ec->clear();
   if (DNEParts.empty())
     return result;
-  for (auto It=DNEParts.rbegin(); It != DNEParts.rend(); ++It)
+  for (auto It = DNEParts.rbegin(); It != DNEParts.rend(); ++It)
     result /= *It;
   return result.lexically_normal();
 }
@@ -1262,56 +1247,52 @@
 
 constexpr path::value_type path::preferred_separator;
 
-path & path::replace_extension(path const & replacement)
-{
-    path p = extension();
-    if (not p.empty()) {
-      __pn_.erase(__pn_.size() - p.native().size());
+path& path::replace_extension(path const& replacement) {
+  path p = extension();
+  if (not p.empty()) {
+    __pn_.erase(__pn_.size() - p.native().size());
+  }
+  if (!replacement.empty()) {
+    if (replacement.native()[0] != '.') {
+      __pn_ += ".";
     }
-    if (!replacement.empty()) {
-        if (replacement.native()[0] != '.') {
-            __pn_ += ".";
-        }
-        __pn_.append(replacement.__pn_);
-    }
-    return *this;
+    __pn_.append(replacement.__pn_);
+  }
+  return *this;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 // path.decompose
 
-string_view_t path::__root_name() const
-{
-    auto PP = PathParser::CreateBegin(__pn_);
-    if (PP.State == PathParser::PS_InRootName)
-      return *PP;
-    return {};
+string_view_t path::__root_name() const {
+  auto PP = PathParser::CreateBegin(__pn_);
+  if (PP.State == PathParser::PS_InRootName)
+    return *PP;
+  return {};
 }
 
-string_view_t path::__root_directory() const
-{
-    auto PP = PathParser::CreateBegin(__pn_);
-    if (PP.State == PathParser::PS_InRootName)
+string_view_t path::__root_directory() const {
+  auto PP = PathParser::CreateBegin(__pn_);
+  if (PP.State == PathParser::PS_InRootName)
+    ++PP;
+  if (PP.State == PathParser::PS_InRootDir)
+    return *PP;
+  return {};
+}
+
+string_view_t path::__root_path_raw() const {
+  auto PP = PathParser::CreateBegin(__pn_);
+  if (PP.State == PathParser::PS_InRootName) {
+    auto NextCh = PP.peek();
+    if (NextCh && *NextCh == '/') {
       ++PP;
-    if (PP.State == PathParser::PS_InRootDir)
-      return *PP;
-    return {};
-}
-
-string_view_t path::__root_path_raw() const
-{
-    auto PP = PathParser::CreateBegin(__pn_);
-    if (PP.State == PathParser::PS_InRootName) {
-      auto NextCh = PP.peek();
-      if (NextCh && *NextCh == '/') {
-        ++PP;
-        return createView(__pn_.data(), &PP.RawEntry.back());
-      }
-      return PP.RawEntry;
+      return createView(__pn_.data(), &PP.RawEntry.back());
     }
-    if (PP.State == PathParser::PS_InRootDir)
-      return *PP;
-    return {};
+    return PP.RawEntry;
+  }
+  if (PP.State == PathParser::PS_InRootDir)
+    return *PP;
+  return {};
 }
 
 static bool ConsumeRootDir(PathParser* PP) {
@@ -1320,62 +1301,57 @@
   return PP->State == PathParser::PS_AtEnd;
 }
 
-string_view_t path::__relative_path() const
-{
+string_view_t path::__relative_path() const {
+  auto PP = PathParser::CreateBegin(__pn_);
+  if (ConsumeRootDir(&PP))
+    return {};
+  return createView(PP.RawEntry.data(), &__pn_.back());
+}
+
+string_view_t path::__parent_path() const {
+  if (empty())
+    return {};
+  // Determine if we have a root path but not a relative path. In that case
+  // return *this.
+  {
     auto PP = PathParser::CreateBegin(__pn_);
     if (ConsumeRootDir(&PP))
+      return __pn_;
+  }
+  // Otherwise remove a single element from the end of the path, and return
+  // a string representing that path
+  {
+    auto PP = PathParser::CreateEnd(__pn_);
+    --PP;
+    if (PP.RawEntry.data() == __pn_.data())
       return {};
-    return createView(PP.RawEntry.data(), &__pn_.back());
+    --PP;
+    return createView(__pn_.data(), &PP.RawEntry.back());
+  }
 }
 
-string_view_t path::__parent_path() const
-{
-    if (empty())
+string_view_t path::__filename() const {
+  if (empty())
+    return {};
+  {
+    PathParser PP = PathParser::CreateBegin(__pn_);
+    if (ConsumeRootDir(&PP))
       return {};
-    // Determine if we have a root path but not a relative path. In that case
-    // return *this.
-    {
-      auto PP = PathParser::CreateBegin(__pn_);
-      if (ConsumeRootDir(&PP))
-        return __pn_;
-    }
-    // Otherwise remove a single element from the end of the path, and return
-    // a string representing that path
-    {
-      auto PP = PathParser::CreateEnd(__pn_);
-      --PP;
-      if (PP.RawEntry.data() == __pn_.data())
-        return {};
-      --PP;
-      return createView(__pn_.data(), &PP.RawEntry.back());
-    }
+  }
+  return *(--PathParser::CreateEnd(__pn_));
 }
 
-string_view_t path::__filename() const
-{
-    if (empty()) return {};
-    {
-      PathParser PP = PathParser::CreateBegin(__pn_);
-      if (ConsumeRootDir(&PP))
-        return {};
-    }
-    return *(--PathParser::CreateEnd(__pn_));
+string_view_t path::__stem() const {
+  return parser::separate_filename(__filename()).first;
 }
 
-string_view_t path::__stem() const
-{
-    return parser::separate_filename(__filename()).first;
-}
-
-string_view_t path::__extension() const
-{
-    return parser::separate_filename(__filename()).second;
+string_view_t path::__extension() const {
+  return parser::separate_filename(__filename()).second;
 }
 
 ////////////////////////////////////////////////////////////////////////////
 // path.gen
 
-
 enum PathPartKind : unsigned char {
   PK_None,
   PK_RootSep,
@@ -1456,7 +1432,7 @@
   }
   // [fs.path.generic]p6.8: If the path is empty, add a dot.
   if (Parts.empty())
-     return ".";
+    return ".";
 
   // [fs.path.generic]p6.7: If the last filename is dot-dot, remove any
   // trailing directory-separator.
@@ -1464,7 +1440,7 @@
 
   path Result;
   Result.__pn_.reserve(Parts.size() + NewPathSize + NeedTrailingSep);
-  for (auto &PK : Parts)
+  for (auto& PK : Parts)
     Result /= PK.first;
 
   if (NeedTrailingSep)
@@ -1490,8 +1466,8 @@
     auto PP = PathParser::CreateBegin(__pn_);
     auto PPBase = PathParser::CreateBegin(base.__pn_);
     auto CheckIterMismatchAtBase = [&]() {
-        return PP.State != PPBase.State && (
-            PP.inRootPath() || PPBase.inRootPath());
+      return PP.State != PPBase.State &&
+             (PP.inRootPath() || PPBase.inRootPath());
     };
     if (PP.State == PathParser::PS_InRootName &&
         PPBase.State == PathParser::PS_InRootName) {
@@ -1500,8 +1476,10 @@
     } else if (CheckIterMismatchAtBase())
       return {};
 
-    if (PP.inRootPath()) ++PP;
-    if (PPBase.inRootPath()) ++PPBase;
+    if (PP.inRootPath())
+      ++PP;
+    if (PPBase.inRootPath())
+      ++PPBase;
     if (CheckIterMismatchAtBase())
       return {};
   }
@@ -1509,8 +1487,7 @@
   // Find the first mismatching element
   auto PP = PathParser::CreateBegin(__pn_);
   auto PPBase = PathParser::CreateBegin(base.__pn_);
-  while (PP && PPBase && PP.State == PPBase.State &&
-         *PP == *PPBase) {
+  while (PP && PPBase && PP.State == PPBase.State && *PP == *PPBase) {
     ++PP;
     ++PPBase;
   }
@@ -1539,18 +1516,20 @@
 ////////////////////////////////////////////////////////////////////////////
 // path.comparisons
 int path::__compare(string_view_t __s) const {
-    auto PP = PathParser::CreateBegin(__pn_);
-    auto PP2 = PathParser::CreateBegin(__s);
-    while (PP && PP2) {
-        int res = (*PP).compare(*PP2);
-        if (res != 0) return res;
-        ++PP; ++PP2;
-    }
-    if (PP.State == PP2.State && !PP)
-        return 0;
-    if (!PP)
-        return -1;
-    return 1;
+  auto PP = PathParser::CreateBegin(__pn_);
+  auto PP2 = PathParser::CreateBegin(__s);
+  while (PP && PP2) {
+    int res = (*PP).compare(*PP2);
+    if (res != 0)
+      return res;
+    ++PP;
+    ++PP2;
+  }
+  if (PP.State == PP2.State && !PP)
+    return 0;
+  if (!PP)
+    return -1;
+  return 1;
 }
 
 ////////////////////////////////////////////////////////////////////////////
@@ -1568,23 +1547,21 @@
 
 ////////////////////////////////////////////////////////////////////////////
 // path.itr
-path::iterator path::begin() const
-{
-    auto PP = PathParser::CreateBegin(__pn_);
-    iterator it;
-    it.__path_ptr_ = this;
-    it.__state_ = static_cast<path::iterator::_ParserState>(PP.State);
-    it.__entry_ = PP.RawEntry;
-    it.__stashed_elem_.__assign_view(*PP);
-    return it;
+path::iterator path::begin() const {
+  auto PP = PathParser::CreateBegin(__pn_);
+  iterator it;
+  it.__path_ptr_ = this;
+  it.__state_ = static_cast<path::iterator::_ParserState>(PP.State);
+  it.__entry_ = PP.RawEntry;
+  it.__stashed_elem_.__assign_view(*PP);
+  return it;
 }
 
-path::iterator path::end() const
-{
-    iterator it{};
-    it.__state_ = path::iterator::_AtEnd;
-    it.__path_ptr_ = this;
-    return it;
+path::iterator path::end() const {
+  iterator it{};
+  it.__state_ = path::iterator::_AtEnd;
+  it.__path_ptr_ = this;
+  return it;
 }
 
 path::iterator& path::iterator::__increment() {
@@ -1706,4 +1683,4 @@
 }
 #endif
 
-_LIBCPP_END_NAMESPACE_EXPERIMENTAL_FILESYSTEM
+_LIBCPP_END_NAMESPACE_FILESYSTEM
diff --git a/test/libcxx/double_include.sh.cpp b/test/libcxx/double_include.sh.cpp
index dfc3d01..c98cc80 100644
--- a/test/libcxx/double_include.sh.cpp
+++ b/test/libcxx/double_include.sh.cpp
@@ -62,6 +62,7 @@
 #include <deque>
 #include <errno.h>
 #include <exception>
+#include <filesystem>
 #include <float.h>
 #include <forward_list>
 #include <fstream>
diff --git a/test/libcxx/experimental/filesystem/version.pass.cpp b/test/libcxx/experimental/filesystem/version.pass.cpp
index 723380a..d5f36a6 100644
--- a/test/libcxx/experimental/filesystem/version.pass.cpp
+++ b/test/libcxx/experimental/filesystem/version.pass.cpp
@@ -7,8 +7,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-// UNSUPPORTED: c++98, c++03
-
 // <experimental/filesystem>
 
 #include <experimental/filesystem>
diff --git a/test/libcxx/experimental/filesystem/class.directory_entry/directory_entry.mods/last_write_time.sh.cpp b/test/libcxx/input.output/filesystems/class.directory_entry/directory_entry.mods/last_write_time.sh.cpp
similarity index 96%
rename from test/libcxx/experimental/filesystem/class.directory_entry/directory_entry.mods/last_write_time.sh.cpp
rename to test/libcxx/input.output/filesystems/class.directory_entry/directory_entry.mods/last_write_time.sh.cpp
index 7f4ed67..6372755 100644
--- a/test/libcxx/experimental/filesystem/class.directory_entry/directory_entry.mods/last_write_time.sh.cpp
+++ b/test/libcxx/input.output/filesystems/class.directory_entry/directory_entry.mods/last_write_time.sh.cpp
@@ -9,11 +9,11 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
-// RUN: %build -I%libcxx_src_root/src/experimental/filesystem
+// RUN: %build -I%libcxx_src_root/src/filesystem
 // RUN: %run
 
 #include "filesystem_include.hpp"
diff --git a/test/libcxx/experimental/filesystem/class.path/path.itr/iterator_db.pass.cpp b/test/libcxx/input.output/filesystems/class.path/path.itr/iterator_db.pass.cpp
similarity index 93%
rename from test/libcxx/experimental/filesystem/class.path/path.itr/iterator_db.pass.cpp
rename to test/libcxx/input.output/filesystems/class.path/path.itr/iterator_db.pass.cpp
index b8b7124..405f9ab 100644
--- a/test/libcxx/experimental/filesystem/class.path/path.itr/iterator_db.pass.cpp
+++ b/test/libcxx/input.output/filesystems/class.path/path.itr/iterator_db.pass.cpp
@@ -13,13 +13,13 @@
 // MODULES_DEFINES: _LIBCPP_DEBUG_USE_EXCEPTIONS
 // MODULES_DEFINES: _LIBCPP_DEBUG=0
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
 #define _LIBCPP_DEBUG 0
 #define _LIBCPP_DEBUG_USE_EXCEPTIONS
-#include <experimental/filesystem>
+#include "filesystem_include.hpp"
 #include <iterator>
 #include <type_traits>
 #include <cassert>
@@ -27,8 +27,6 @@
 #include "test_macros.h"
 #include "filesystem_test_helper.hpp"
 
-namespace fs = std::experimental::filesystem;
-
 int main() {
   using namespace fs;
   using ExType = std::__libcpp_debug_exception;
diff --git a/test/libcxx/experimental/filesystem/class.path/path.itr/reverse_iterator_produces_diagnostic.fail.cpp b/test/libcxx/input.output/filesystems/class.path/path.itr/reverse_iterator_produces_diagnostic.fail.cpp
similarity index 86%
rename from test/libcxx/experimental/filesystem/class.path/path.itr/reverse_iterator_produces_diagnostic.fail.cpp
rename to test/libcxx/input.output/filesystems/class.path/path.itr/reverse_iterator_produces_diagnostic.fail.cpp
index 5a6f530..992cdeb 100644
--- a/test/libcxx/experimental/filesystem/class.path/path.itr/reverse_iterator_produces_diagnostic.fail.cpp
+++ b/test/libcxx/input.output/filesystems/class.path/path.itr/reverse_iterator_produces_diagnostic.fail.cpp
@@ -9,16 +9,14 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
-#include <experimental/filesystem>
+#include "filesystem_include.hpp"
 #include <iterator>
 
 
-namespace fs = std::experimental::filesystem;
-
 int main() {
   using namespace fs;
   using RIt = std::reverse_iterator<path::iterator>;
diff --git a/test/libcxx/experimental/filesystem/class.path/path.req/is_pathable.pass.cpp b/test/libcxx/input.output/filesystems/class.path/path.req/is_pathable.pass.cpp
similarity index 96%
rename from test/libcxx/experimental/filesystem/class.path/path.req/is_pathable.pass.cpp
rename to test/libcxx/input.output/filesystems/class.path/path.req/is_pathable.pass.cpp
index 61d3225..ff0cc59 100644
--- a/test/libcxx/experimental/filesystem/class.path/path.req/is_pathable.pass.cpp
+++ b/test/libcxx/input.output/filesystems/class.path/path.req/is_pathable.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // template <class Tp> struct __is_pathable
 
@@ -21,7 +21,7 @@
 // * A character array, which points to a NTCTS after array-to-pointer decay.
 
 
-#include <experimental/filesystem>
+#include "filesystem_include.hpp"
 #include <type_traits>
 #include <cassert>
 
@@ -30,8 +30,6 @@
 #include "min_allocator.h"
 #include "constexpr_char_traits.hpp"
 
-namespace fs = std::experimental::filesystem;
-
 using fs::__is_pathable;
 
 template <class Tp>
diff --git a/test/libcxx/experimental/filesystem/convert_file_time.sh.cpp b/test/libcxx/input.output/filesystems/convert_file_time.sh.cpp
similarity index 97%
rename from test/libcxx/experimental/filesystem/convert_file_time.sh.cpp
rename to test/libcxx/input.output/filesystems/convert_file_time.sh.cpp
index 9182366..21a1a49 100644
--- a/test/libcxx/experimental/filesystem/convert_file_time.sh.cpp
+++ b/test/libcxx/input.output/filesystems/convert_file_time.sh.cpp
@@ -9,14 +9,14 @@
 
 // UNSUPPORTED: c++98, c++03, c++11
 
-// <experimental/filesystem>
+// <filesystem>
 
 // typedef TrivialClock file_time_type;
 
-// RUN: %build -I%libcxx_src_root/src/experimental/filesystem
+// RUN: %build -I%libcxx_src_root/src/filesystem
 // RUN: %run
 
-#include <experimental/filesystem>
+#include <filesystem>
 #include <chrono>
 #include <type_traits>
 #include <limits>
@@ -30,7 +30,7 @@
 #endif
 
 using namespace std::chrono;
-namespace fs = std::experimental::filesystem;
+namespace fs = std::__fs::filesystem;
 using fs::file_time_type;
 using fs::detail::time_util;
 
diff --git a/test/libcxx/experimental/filesystem/lit.local.cfg b/test/libcxx/input.output/filesystems/lit.local.cfg
similarity index 100%
rename from test/libcxx/experimental/filesystem/lit.local.cfg
rename to test/libcxx/input.output/filesystems/lit.local.cfg
diff --git a/test/libcxx/input.output/filesystems/version.pass.cpp b/test/libcxx/input.output/filesystems/version.pass.cpp
new file mode 100644
index 0000000..f680217
--- /dev/null
+++ b/test/libcxx/input.output/filesystems/version.pass.cpp
@@ -0,0 +1,20 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <filesystem>
+
+#include <filesystem>
+
+#ifndef _LIBCPP_VERSION
+#error _LIBCPP_VERSION not defined
+#endif
+
+int main()
+{
+}
diff --git a/test/std/input.output/file.streams/fstreams/filebuf.members/open_path.pass.cpp b/test/std/input.output/file.streams/fstreams/filebuf.members/open_path.pass.cpp
new file mode 100644
index 0000000..02e2b60
--- /dev/null
+++ b/test/std/input.output/file.streams/fstreams/filebuf.members/open_path.pass.cpp
@@ -0,0 +1,56 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+
+// <fstream>
+
+// basic_filebuf<charT,traits>* open(const filesystem::path& p, ios_base::openmode mode);
+
+#include <fstream>
+#include <filesystem>
+#include <cassert>
+#include "platform_support.h"
+
+namespace fs = std::filesystem;
+
+int main() {
+
+  fs::path p = get_temp_file_name();
+  {
+    std::filebuf f;
+    assert(f.open(p, std::ios_base::out) != 0);
+    assert(f.is_open());
+    assert(f.sputn("123", 3) == 3);
+  }
+  {
+    std::filebuf f;
+    assert(f.open(p, std::ios_base::in) != 0);
+    assert(f.is_open());
+    assert(f.sbumpc() == '1');
+    assert(f.sbumpc() == '2');
+    assert(f.sbumpc() == '3');
+  }
+  std::remove(p.c_str());
+  {
+    std::wfilebuf f;
+    assert(f.open(p, std::ios_base::out) != 0);
+    assert(f.is_open());
+    assert(f.sputn(L"123", 3) == 3);
+  }
+  {
+    std::wfilebuf f;
+    assert(f.open(p, std::ios_base::in) != 0);
+    assert(f.is_open());
+    assert(f.sbumpc() == L'1');
+    assert(f.sbumpc() == L'2');
+    assert(f.sbumpc() == L'3');
+  }
+  remove(p.c_str());
+}
diff --git a/test/std/input.output/file.streams/fstreams/fstream.cons/path.pass.cpp b/test/std/input.output/file.streams/fstreams/fstream.cons/path.pass.cpp
new file mode 100644
index 0000000..d9b4a8c
--- /dev/null
+++ b/test/std/input.output/file.streams/fstreams/fstream.cons/path.pass.cpp
@@ -0,0 +1,49 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+
+// <fstream>
+
+// plate <class charT, class traits = char_traits<charT> >
+// class basic_fstream
+
+// explicit basic_fstream(const filesystem::path& s,
+//     ios_base::openmode mode = ios_base::in|ios_base::out);
+
+#include <fstream>
+#include <filesystem>
+#include <cassert>
+#include "platform_support.h"
+
+namespace fs = std::filesystem;
+
+int main() {
+  fs::path p = get_temp_file_name();
+  {
+    std::fstream fs(p, std::ios_base::in | std::ios_base::out |
+                           std::ios_base::trunc);
+    double x = 0;
+    fs << 3.25;
+    fs.seekg(0);
+    fs >> x;
+    assert(x == 3.25);
+  }
+  std::remove(p.c_str());
+  {
+    std::wfstream fs(p, std::ios_base::in | std::ios_base::out |
+                            std::ios_base::trunc);
+    double x = 0;
+    fs << 3.25;
+    fs.seekg(0);
+    fs >> x;
+    assert(x == 3.25);
+  }
+  std::remove(p.c_str());
+}
diff --git a/test/std/input.output/file.streams/fstreams/fstream.members/open_path.pass.cpp b/test/std/input.output/file.streams/fstreams/fstream.members/open_path.pass.cpp
new file mode 100644
index 0000000..69cbf3f
--- /dev/null
+++ b/test/std/input.output/file.streams/fstreams/fstream.members/open_path.pass.cpp
@@ -0,0 +1,52 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+
+// <fstream>
+
+// plate <class charT, class traits = char_traits<charT> >
+// class basic_fstream
+
+// void open(const filesystem::path& s, ios_base::openmode mode = ios_base::in|ios_base::out);
+
+#include <fstream>
+#include <filesystem>
+#include <cassert>
+#include "platform_support.h"
+
+int main() {
+  std::filesystem::path p = get_temp_file_name();
+  {
+    std::fstream stream;
+    assert(!stream.is_open());
+    stream.open(p,
+                std::ios_base::in | std::ios_base::out | std::ios_base::trunc);
+    assert(stream.is_open());
+    double x = 0;
+    stream << 3.25;
+    stream.seekg(0);
+    stream >> x;
+    assert(x == 3.25);
+  }
+  std::remove(p.c_str());
+  {
+    std::wfstream stream;
+    assert(!stream.is_open());
+    stream.open(p,
+                std::ios_base::in | std::ios_base::out | std::ios_base::trunc);
+    assert(stream.is_open());
+    double x = 0;
+    stream << 3.25;
+    stream.seekg(0);
+    stream >> x;
+    assert(x == 3.25);
+  }
+  std::remove(p.c_str());
+}
diff --git a/test/std/input.output/file.streams/fstreams/ifstream.cons/path.pass.cpp b/test/std/input.output/file.streams/fstreams/ifstream.cons/path.pass.cpp
new file mode 100644
index 0000000..99eae3a
--- /dev/null
+++ b/test/std/input.output/file.streams/fstreams/ifstream.cons/path.pass.cpp
@@ -0,0 +1,53 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+
+// <fstream>
+
+// template <class charT, class traits = char_traits<charT> >
+// class basic_ifstream
+
+// explicit basic_ifstream(const filesystem::path& s,
+//     ios_base::openmode mode = ios_base::in);
+
+#include <fstream>
+#include <filesystem>
+#include <cassert>
+
+namespace fs = std::filesystem;
+
+int main() {
+  {
+    fs::path p;
+    static_assert(!std::is_convertible<fs::path, std::ifstream>::value,
+                  "ctor should be explicit");
+    static_assert(std::is_constructible<std::ifstream, fs::path const&,
+                                        std::ios_base::openmode>::value,
+                  "");
+  }
+  {
+    std::ifstream fs(fs::path("test.dat"));
+    double x = 0;
+    fs >> x;
+    assert(x == 3.25);
+  }
+  // std::ifstream(const fs::path&, std::ios_base::openmode) is tested in
+  // test/std/input.output/file.streams/fstreams/ofstream.cons/string.pass.cpp
+  // which creates writable files.
+  {
+    std::wifstream fs(fs::path("test.dat"));
+    double x = 0;
+    fs >> x;
+    assert(x == 3.25);
+  }
+  // std::wifstream(const fs::path&, std::ios_base::openmode) is tested in
+  // test/std/input.output/file.streams/fstreams/ofstream.cons/string.pass.cpp
+  // which creates writable files.
+}
diff --git a/test/std/input.output/file.streams/fstreams/ifstream.members/open_path.pass.cpp b/test/std/input.output/file.streams/fstreams/ifstream.members/open_path.pass.cpp
new file mode 100644
index 0000000..82f7c64
--- /dev/null
+++ b/test/std/input.output/file.streams/fstreams/ifstream.members/open_path.pass.cpp
@@ -0,0 +1,48 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+
+// <fstream>
+
+// template <class charT, class traits = char_traits<charT> >
+// class basic_ifstream
+
+// void open(const filesystem::path& s, ios_base::openmode mode = ios_base::in);
+
+#include <fstream>
+#include <filesystem>
+#include <cassert>
+
+int main() {
+  {
+    std::ifstream fs;
+    assert(!fs.is_open());
+    char c = 'a';
+    fs >> c;
+    assert(fs.fail());
+    assert(c == 'a');
+    fs.open(std::filesystem::path("test.dat"));
+    assert(fs.is_open());
+    fs >> c;
+    assert(c == 'r');
+  }
+  {
+    std::wifstream fs;
+    assert(!fs.is_open());
+    wchar_t c = L'a';
+    fs >> c;
+    assert(fs.fail());
+    assert(c == L'a');
+    fs.open(std::filesystem::path("test.dat"));
+    assert(fs.is_open());
+    fs >> c;
+    assert(c == L'r');
+  }
+}
diff --git a/test/std/input.output/file.streams/fstreams/ofstream.cons/path.pass.cpp b/test/std/input.output/file.streams/fstreams/ofstream.cons/path.pass.cpp
new file mode 100644
index 0000000..9a23384
--- /dev/null
+++ b/test/std/input.output/file.streams/fstreams/ofstream.cons/path.pass.cpp
@@ -0,0 +1,69 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+
+// <fstream>
+
+// plate <class charT, class traits = char_traits<charT> >
+// class basic_ofstream
+
+// explicit basic_ofstream(const filesystem::path& s, ios_base::openmode mode = ios_base::out);
+
+#include <fstream>
+#include <filesystem>
+#include <cassert>
+#include "platform_support.h"
+
+namespace fs = std::filesystem;
+
+int main() {
+  fs::path p = get_temp_file_name();
+  {
+    static_assert(!std::is_convertible<fs::path, std::ofstream>::value,
+                  "ctor should be explicit");
+    static_assert(std::is_constructible<std::ofstream, fs::path const&,
+                                        std::ios_base::openmode>::value,
+                  "");
+  }
+  {
+    std::ofstream stream(p);
+    stream << 3.25;
+  }
+  {
+    std::ifstream stream(p);
+    double x = 0;
+    stream >> x;
+    assert(x == 3.25);
+  }
+  {
+    std::ifstream stream(p, std::ios_base::out);
+    double x = 0;
+    stream >> x;
+    assert(x == 3.25);
+  }
+  std::remove(p.c_str());
+  {
+    std::wofstream stream(p);
+    stream << 3.25;
+  }
+  {
+    std::wifstream stream(p);
+    double x = 0;
+    stream >> x;
+    assert(x == 3.25);
+  }
+  {
+    std::wifstream stream(p, std::ios_base::out);
+    double x = 0;
+    stream >> x;
+    assert(x == 3.25);
+  }
+  std::remove(p.c_str());
+}
diff --git a/test/std/input.output/file.streams/fstreams/ofstream.members/open_path.pass.cpp b/test/std/input.output/file.streams/fstreams/ofstream.members/open_path.pass.cpp
new file mode 100644
index 0000000..867998b
--- /dev/null
+++ b/test/std/input.output/file.streams/fstreams/ofstream.members/open_path.pass.cpp
@@ -0,0 +1,62 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+
+// <fstream>
+
+// plate <class charT, class traits = char_traits<charT> >
+// class basic_ofstream
+
+// void open(const filesystem::path& s, ios_base::openmode mode = ios_base::out);
+
+#include <fstream>
+#include <filesystem>
+#include <cassert>
+#include "platform_support.h"
+
+namespace fs = std::filesystem;
+
+int main() {
+  fs::path p = get_temp_file_name();
+  {
+    std::ofstream fs;
+    assert(!fs.is_open());
+    char c = 'a';
+    fs << c;
+    assert(fs.fail());
+    fs.open(p);
+    assert(fs.is_open());
+    fs << c;
+  }
+  {
+    std::ifstream fs(p.c_str());
+    char c = 0;
+    fs >> c;
+    assert(c == 'a');
+  }
+  std::remove(p.c_str());
+  {
+    std::wofstream fs;
+    assert(!fs.is_open());
+    wchar_t c = L'a';
+    fs << c;
+    assert(fs.fail());
+    fs.open(p);
+    assert(fs.is_open());
+    fs << c;
+  }
+  {
+    std::wifstream fs(p.c_str());
+    wchar_t c = 0;
+    fs >> c;
+    assert(c == L'a');
+  }
+  std::remove(p.c_str());
+}
diff --git a/test/std/experimental/filesystem/Inputs/static_test_env/bad_symlink b/test/std/input.output/filesystems/Inputs/static_test_env/bad_symlink
similarity index 100%
rename from test/std/experimental/filesystem/Inputs/static_test_env/bad_symlink
rename to test/std/input.output/filesystems/Inputs/static_test_env/bad_symlink
diff --git a/test/std/experimental/filesystem/Inputs/static_test_env/dir1/dir2/afile3 b/test/std/input.output/filesystems/Inputs/static_test_env/dir1/dir2/afile3
similarity index 100%
rename from test/std/experimental/filesystem/Inputs/static_test_env/dir1/dir2/afile3
rename to test/std/input.output/filesystems/Inputs/static_test_env/dir1/dir2/afile3
diff --git a/test/std/experimental/filesystem/Inputs/static_test_env/dir1/dir2/dir3/file5 b/test/std/input.output/filesystems/Inputs/static_test_env/dir1/dir2/dir3/file5
similarity index 100%
rename from test/std/experimental/filesystem/Inputs/static_test_env/dir1/dir2/dir3/file5
rename to test/std/input.output/filesystems/Inputs/static_test_env/dir1/dir2/dir3/file5
diff --git a/test/std/experimental/filesystem/Inputs/static_test_env/dir1/dir2/file4 b/test/std/input.output/filesystems/Inputs/static_test_env/dir1/dir2/file4
similarity index 100%
rename from test/std/experimental/filesystem/Inputs/static_test_env/dir1/dir2/file4
rename to test/std/input.output/filesystems/Inputs/static_test_env/dir1/dir2/file4
diff --git a/test/std/experimental/filesystem/Inputs/static_test_env/dir1/dir2/symlink_to_dir3 b/test/std/input.output/filesystems/Inputs/static_test_env/dir1/dir2/symlink_to_dir3
similarity index 100%
rename from test/std/experimental/filesystem/Inputs/static_test_env/dir1/dir2/symlink_to_dir3
rename to test/std/input.output/filesystems/Inputs/static_test_env/dir1/dir2/symlink_to_dir3
diff --git a/test/std/experimental/filesystem/Inputs/static_test_env/dir1/file1 b/test/std/input.output/filesystems/Inputs/static_test_env/dir1/file1
similarity index 100%
rename from test/std/experimental/filesystem/Inputs/static_test_env/dir1/file1
rename to test/std/input.output/filesystems/Inputs/static_test_env/dir1/file1
diff --git a/test/std/experimental/filesystem/Inputs/static_test_env/dir1/file2 b/test/std/input.output/filesystems/Inputs/static_test_env/dir1/file2
similarity index 100%
rename from test/std/experimental/filesystem/Inputs/static_test_env/dir1/file2
rename to test/std/input.output/filesystems/Inputs/static_test_env/dir1/file2
diff --git a/test/std/experimental/filesystem/Inputs/static_test_env/empty_file b/test/std/input.output/filesystems/Inputs/static_test_env/empty_file
similarity index 100%
rename from test/std/experimental/filesystem/Inputs/static_test_env/empty_file
rename to test/std/input.output/filesystems/Inputs/static_test_env/empty_file
diff --git a/test/std/experimental/filesystem/Inputs/static_test_env/non_empty_file b/test/std/input.output/filesystems/Inputs/static_test_env/non_empty_file
similarity index 100%
rename from test/std/experimental/filesystem/Inputs/static_test_env/non_empty_file
rename to test/std/input.output/filesystems/Inputs/static_test_env/non_empty_file
diff --git a/test/std/experimental/filesystem/Inputs/static_test_env/symlink_to_dir b/test/std/input.output/filesystems/Inputs/static_test_env/symlink_to_dir
similarity index 100%
rename from test/std/experimental/filesystem/Inputs/static_test_env/symlink_to_dir
rename to test/std/input.output/filesystems/Inputs/static_test_env/symlink_to_dir
diff --git a/test/std/experimental/filesystem/Inputs/static_test_env/symlink_to_empty_file b/test/std/input.output/filesystems/Inputs/static_test_env/symlink_to_empty_file
similarity index 100%
rename from test/std/experimental/filesystem/Inputs/static_test_env/symlink_to_empty_file
rename to test/std/input.output/filesystems/Inputs/static_test_env/symlink_to_empty_file
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/copy.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/copy.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/copy.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/copy.pass.cpp
index f463029..a81d5ea 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/copy.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/copy.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/copy_assign.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/copy_assign.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/copy_assign.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/copy_assign.pass.cpp
index 447d409..2042072 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/copy_assign.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/copy_assign.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/default.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default.pass.cpp
similarity index 96%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/default.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default.pass.cpp
index dd4543d..1d83cc6 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/default.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/default_const.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default_const.pass.cpp
similarity index 96%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/default_const.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default_const.pass.cpp
index a94134c..240541d 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/default_const.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/default_const.pass.cpp
@@ -10,7 +10,7 @@
 // UNSUPPORTED: c++98, c++03
 // XFAIL: apple-clang-7, clang-3.7, clang-3.8
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/move.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/move.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/move.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/move.pass.cpp
index f22bf1c..238a854 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/move.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/move.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/move_assign.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/move_assign.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/move_assign.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/move_assign.pass.cpp
index abd9bc8..f104980 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/move_assign.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/move_assign.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/path.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/path.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/path.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/path.pass.cpp
index b6ecd3f..b06bd12 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.cons/path.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.cons/path.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.mods/assign.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.mods/assign.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.mods/assign.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.mods/assign.pass.cpp
index 70f0de3..d19c8c2 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.mods/assign.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.mods/assign.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.mods/refresh.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.mods/refresh.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.mods/refresh.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.mods/refresh.pass.cpp
index 74c73f0..575f0d5 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.mods/refresh.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.mods/refresh.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.mods/replace_filename.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.mods/replace_filename.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.mods/replace_filename.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.mods/replace_filename.pass.cpp
index 24b5ebf..4a9b76d 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.mods/replace_filename.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.mods/replace_filename.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/comparisons.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/comparisons.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/comparisons.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/comparisons.pass.cpp
index 48997ca..7df36fe 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/comparisons.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/comparisons.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/file_size.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/file_size.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/file_size.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/file_size.pass.cpp
index a38b10c..04dec92 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/file_size.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/file_size.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/file_type_obs.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/file_type_obs.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/file_type_obs.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/file_type_obs.pass.cpp
index a028de4..2a0d80c 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/file_type_obs.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/file_type_obs.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/hard_link_count.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/hard_link_count.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/hard_link_count.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/hard_link_count.pass.cpp
index d11457d..17124c1 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/hard_link_count.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/hard_link_count.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/last_write_time.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/last_write_time.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/last_write_time.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/last_write_time.pass.cpp
index 3d51972..afdd47a 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/last_write_time.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/last_write_time.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/path.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/path.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/path.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/path.pass.cpp
index 80168ef..2abb13d 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/path.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/path.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/status.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/status.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/status.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/status.pass.cpp
index 1f15850..ec65446 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/status.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/status.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/symlink_status.pass.cpp b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/symlink_status.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/symlink_status.pass.cpp
rename to test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/symlink_status.pass.cpp
index ed6aca2..e8850c3 100644
--- a/test/std/experimental/filesystem/class.directory_entry/directory_entry.obs/symlink_status.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_entry/directory_entry.obs/symlink_status.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_entry
 
diff --git a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/copy.pass.cpp b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/copy.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/copy.pass.cpp
rename to test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/copy.pass.cpp
index 777e614..ac224ac 100644
--- a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/copy.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/copy.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/copy_assign.pass.cpp b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/copy_assign.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/copy_assign.pass.cpp
rename to test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/copy_assign.pass.cpp
index 067e6c6..3f08e40 100644
--- a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/copy_assign.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/copy_assign.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/ctor.pass.cpp b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/ctor.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/ctor.pass.cpp
rename to test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/ctor.pass.cpp
index 6a24a52..0a33544 100644
--- a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/ctor.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/ctor.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/default_ctor.pass.cpp b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/default_ctor.pass.cpp
similarity index 96%
rename from test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/default_ctor.pass.cpp
rename to test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/default_ctor.pass.cpp
index 787f397..21c4ed3 100644
--- a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/default_ctor.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/default_ctor.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/increment.pass.cpp b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/increment.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/increment.pass.cpp
rename to test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/increment.pass.cpp
index ad55e05..7ec814b 100644
--- a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/increment.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/increment.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/move.pass.cpp b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/move.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/move.pass.cpp
rename to test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/move.pass.cpp
index 97a34a9..a2bf2ac 100644
--- a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/move.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/move.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/move_assign.pass.cpp b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/move_assign.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/move_assign.pass.cpp
rename to test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/move_assign.pass.cpp
index 5382566..1c72243 100644
--- a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.members/move_assign.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.members/move_assign.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.nonmembers/begin_end.pass.cpp b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.nonmembers/begin_end.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.directory_iterator/directory_iterator.nonmembers/begin_end.pass.cpp
rename to test/std/input.output/filesystems/class.directory_iterator/directory_iterator.nonmembers/begin_end.pass.cpp
index 95bb78c..71e8e55 100644
--- a/test/std/experimental/filesystem/class.directory_iterator/directory_iterator.nonmembers/begin_end.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_iterator/directory_iterator.nonmembers/begin_end.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.directory_iterator/types.pass.cpp b/test/std/input.output/filesystems/class.directory_iterator/types.pass.cpp
similarity index 96%
rename from test/std/experimental/filesystem/class.directory_iterator/types.pass.cpp
rename to test/std/input.output/filesystems/class.directory_iterator/types.pass.cpp
index ca583be..4619083 100644
--- a/test/std/experimental/filesystem/class.directory_iterator/types.pass.cpp
+++ b/test/std/input.output/filesystems/class.directory_iterator/types.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.file_status/file_status.cons.pass.cpp b/test/std/input.output/filesystems/class.file_status/file_status.cons.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.file_status/file_status.cons.pass.cpp
rename to test/std/input.output/filesystems/class.file_status/file_status.cons.pass.cpp
index 4c7d5e3..6676c7b 100644
--- a/test/std/experimental/filesystem/class.file_status/file_status.cons.pass.cpp
+++ b/test/std/input.output/filesystems/class.file_status/file_status.cons.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class file_status
 
diff --git a/test/std/experimental/filesystem/class.file_status/file_status.mods.pass.cpp b/test/std/input.output/filesystems/class.file_status/file_status.mods.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.file_status/file_status.mods.pass.cpp
rename to test/std/input.output/filesystems/class.file_status/file_status.mods.pass.cpp
index 5492ccd..4cbf206 100644
--- a/test/std/experimental/filesystem/class.file_status/file_status.mods.pass.cpp
+++ b/test/std/input.output/filesystems/class.file_status/file_status.mods.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class file_status
 
diff --git a/test/std/experimental/filesystem/class.file_status/file_status.obs.pass.cpp b/test/std/input.output/filesystems/class.file_status/file_status.obs.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.file_status/file_status.obs.pass.cpp
rename to test/std/input.output/filesystems/class.file_status/file_status.obs.pass.cpp
index 462670f..89739b7 100644
--- a/test/std/experimental/filesystem/class.file_status/file_status.obs.pass.cpp
+++ b/test/std/input.output/filesystems/class.file_status/file_status.obs.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class file_status
 
diff --git a/test/std/experimental/filesystem/class.filesystem_error/filesystem_error.members.pass.cpp b/test/std/input.output/filesystems/class.filesystem_error/filesystem_error.members.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.filesystem_error/filesystem_error.members.pass.cpp
rename to test/std/input.output/filesystems/class.filesystem_error/filesystem_error.members.pass.cpp
index e9b117a..b7484df 100644
--- a/test/std/experimental/filesystem/class.filesystem_error/filesystem_error.members.pass.cpp
+++ b/test/std/input.output/filesystems/class.filesystem_error/filesystem_error.members.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class filesystem_error
 
diff --git a/test/std/experimental/filesystem/class.path/path.itr/iterator.pass.cpp b/test/std/input.output/filesystems/class.path/path.itr/iterator.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.path/path.itr/iterator.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.itr/iterator.pass.cpp
index 0ea672b..b7a0383 100644
--- a/test/std/experimental/filesystem/class.path/path.itr/iterator.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.itr/iterator.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.append.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.append.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.path/path.member/path.append.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.append.pass.cpp
index 11bc5dd..a02ef18 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.append.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.append.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.assign/braced_init.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.assign/braced_init.pass.cpp
similarity index 95%
rename from test/std/experimental/filesystem/class.path/path.member/path.assign/braced_init.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.assign/braced_init.pass.cpp
index bbf3313..fe677c3 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.assign/braced_init.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.assign/braced_init.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.assign/copy.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.assign/copy.pass.cpp
similarity index 96%
rename from test/std/experimental/filesystem/class.path/path.member/path.assign/copy.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.assign/copy.pass.cpp
index 8b54be6..a0575e6 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.assign/copy.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.assign/copy.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.assign/move.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.assign/move.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.path/path.member/path.assign/move.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.assign/move.pass.cpp
index c5cb37f..71fa47d 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.assign/move.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.assign/move.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.assign/source.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.assign/source.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.path/path.member/path.assign/source.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.assign/source.pass.cpp
index 2e064fa..92eff6e 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.assign/source.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.assign/source.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.compare.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.compare.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.path/path.member/path.compare.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.compare.pass.cpp
index a2af094..7791097 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.compare.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.compare.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.concat.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.concat.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.path/path.member/path.concat.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.concat.pass.cpp
index 13203d6..03d5134 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.concat.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.concat.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.construct/copy.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.construct/copy.pass.cpp
similarity index 96%
rename from test/std/experimental/filesystem/class.path/path.member/path.construct/copy.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.construct/copy.pass.cpp
index 14b4b38..69bdb74 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.construct/copy.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.construct/copy.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.construct/default.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.construct/default.pass.cpp
similarity index 95%
rename from test/std/experimental/filesystem/class.path/path.member/path.construct/default.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.construct/default.pass.cpp
index fddeff9..aa4b03e 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.construct/default.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.construct/default.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.construct/move.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.construct/move.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.path/path.member/path.construct/move.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.construct/move.pass.cpp
index 16f89d0..2e8cce2 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.construct/move.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.construct/move.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.construct/source.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.construct/source.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.path/path.member/path.construct/source.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.construct/source.pass.cpp
index a7c14f3..39d63f4 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.construct/source.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.construct/source.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.decompose/empty.fail.cpp b/test/std/input.output/filesystems/class.path/path.member/path.decompose/empty.fail.cpp
similarity index 95%
rename from test/std/experimental/filesystem/class.path/path.member/path.decompose/empty.fail.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.decompose/empty.fail.cpp
index ecc4c0c..1a722d7 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.decompose/empty.fail.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.decompose/empty.fail.cpp
@@ -8,7 +8,7 @@
 //
 //===----------------------------------------------------------------------===//
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.decompose/path.decompose.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.decompose/path.decompose.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.path/path.member/path.decompose/path.decompose.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.decompose/path.decompose.pass.cpp
index f959e43..4eb15cd 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.decompose/path.decompose.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.decompose/path.decompose.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.gen/lexically_normal.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_normal.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.path/path.member/path.gen/lexically_normal.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_normal.pass.cpp
index c897ab6..3e2fdd0 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.gen/lexically_normal.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_normal.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp
index 8b56a19..52c577b 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.gen/lexically_relative_and_proximate.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.generic.obs/generic_string_alloc.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/generic_string_alloc.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.path/path.member/path.generic.obs/generic_string_alloc.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.generic.obs/generic_string_alloc.pass.cpp
index a757cbb..93c49a6 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.generic.obs/generic_string_alloc.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/generic_string_alloc.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.generic.obs/named_overloads.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/named_overloads.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.path/path.member/path.generic.obs/named_overloads.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.generic.obs/named_overloads.pass.cpp
index 56b2787..d41ab61 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.generic.obs/named_overloads.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.generic.obs/named_overloads.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.modifiers/clear.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.modifiers/clear.pass.cpp
similarity index 96%
rename from test/std/experimental/filesystem/class.path/path.member/path.modifiers/clear.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.modifiers/clear.pass.cpp
index 1d69757..fca6426 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.modifiers/clear.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.modifiers/clear.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.modifiers/make_preferred.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.modifiers/make_preferred.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.path/path.member/path.modifiers/make_preferred.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.modifiers/make_preferred.pass.cpp
index b09806c..ec914b1 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.modifiers/make_preferred.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.modifiers/make_preferred.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.modifiers/remove_filename.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.modifiers/remove_filename.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.path/path.member/path.modifiers/remove_filename.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.modifiers/remove_filename.pass.cpp
index ec885f1..b4019e7 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.modifiers/remove_filename.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.modifiers/remove_filename.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.modifiers/replace_extension.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_extension.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.path/path.member/path.modifiers/replace_extension.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_extension.pass.cpp
index 2e7d925..c118b87 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.modifiers/replace_extension.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_extension.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.modifiers/replace_filename.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_filename.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.path/path.member/path.modifiers/replace_filename.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_filename.pass.cpp
index bfb3b6a..07cd327 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.modifiers/replace_filename.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.modifiers/replace_filename.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.modifiers/swap.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.modifiers/swap.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.path/path.member/path.modifiers/swap.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.modifiers/swap.pass.cpp
index 3aac1ed..eecfe42 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.modifiers/swap.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.modifiers/swap.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.native.obs/c_str.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.native.obs/c_str.pass.cpp
similarity index 96%
rename from test/std/experimental/filesystem/class.path/path.member/path.native.obs/c_str.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.native.obs/c_str.pass.cpp
index f907410..e035764 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.native.obs/c_str.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.native.obs/c_str.pass.cpp
@@ -10,7 +10,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.native.obs/named_overloads.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.native.obs/named_overloads.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.path/path.member/path.native.obs/named_overloads.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.native.obs/named_overloads.pass.cpp
index 9034ad4..bb0f58c 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.native.obs/named_overloads.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.native.obs/named_overloads.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.native.obs/native.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.native.obs/native.pass.cpp
similarity index 96%
rename from test/std/experimental/filesystem/class.path/path.member/path.native.obs/native.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.native.obs/native.pass.cpp
index 35ea493..ca02b86 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.native.obs/native.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.native.obs/native.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.native.obs/operator_string.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.native.obs/operator_string.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.path/path.member/path.native.obs/operator_string.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.native.obs/operator_string.pass.cpp
index 9aa1b14..4f5f77d 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.native.obs/operator_string.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.native.obs/operator_string.pass.cpp
@@ -10,7 +10,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.native.obs/string_alloc.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.native.obs/string_alloc.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.path/path.member/path.native.obs/string_alloc.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.native.obs/string_alloc.pass.cpp
index 503c29c..744ad4d 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.native.obs/string_alloc.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.native.obs/string_alloc.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.member/path.query/tested_in_path_decompose.pass.cpp b/test/std/input.output/filesystems/class.path/path.member/path.query/tested_in_path_decompose.pass.cpp
similarity index 96%
rename from test/std/experimental/filesystem/class.path/path.member/path.query/tested_in_path_decompose.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.member/path.query/tested_in_path_decompose.pass.cpp
index 9cf37d4..be662fc 100644
--- a/test/std/experimental/filesystem/class.path/path.member/path.query/tested_in_path_decompose.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.member/path.query/tested_in_path_decompose.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.nonmember/append_op.pass.cpp b/test/std/input.output/filesystems/class.path/path.nonmember/append_op.pass.cpp
similarity index 95%
rename from test/std/experimental/filesystem/class.path/path.nonmember/append_op.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.nonmember/append_op.pass.cpp
index 3648da5..09498bf 100644
--- a/test/std/experimental/filesystem/class.path/path.nonmember/append_op.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.nonmember/append_op.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // path operator/(path const&, path const&);
 
diff --git a/test/std/experimental/filesystem/class.path/path.nonmember/comparison_ops_tested_elsewhere.pass.cpp b/test/std/input.output/filesystems/class.path/path.nonmember/comparison_ops_tested_elsewhere.pass.cpp
similarity index 100%
rename from test/std/experimental/filesystem/class.path/path.nonmember/comparison_ops_tested_elsewhere.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.nonmember/comparison_ops_tested_elsewhere.pass.cpp
diff --git a/test/std/experimental/filesystem/class.path/path.nonmember/hash_value_tested_elswhere.pass.cpp b/test/std/input.output/filesystems/class.path/path.nonmember/hash_value_tested_elswhere.pass.cpp
similarity index 100%
rename from test/std/experimental/filesystem/class.path/path.nonmember/hash_value_tested_elswhere.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.nonmember/hash_value_tested_elswhere.pass.cpp
diff --git a/test/std/experimental/filesystem/class.path/path.nonmember/path.factory.pass.cpp b/test/std/input.output/filesystems/class.path/path.nonmember/path.factory.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.path/path.nonmember/path.factory.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.nonmember/path.factory.pass.cpp
index 5d9194b..96b8286 100644
--- a/test/std/experimental/filesystem/class.path/path.nonmember/path.factory.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.nonmember/path.factory.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // template <class Source>
 //    path u8path(Source const&);
diff --git a/test/std/experimental/filesystem/class.path/path.nonmember/path.io.pass.cpp b/test/std/input.output/filesystems/class.path/path.nonmember/path.io.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.path/path.nonmember/path.io.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.nonmember/path.io.pass.cpp
index 58e333a..7902289 100644
--- a/test/std/experimental/filesystem/class.path/path.nonmember/path.io.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.nonmember/path.io.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.nonmember/path.io.unicode_bug.pass.cpp b/test/std/input.output/filesystems/class.path/path.nonmember/path.io.unicode_bug.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.path/path.nonmember/path.io.unicode_bug.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.nonmember/path.io.unicode_bug.pass.cpp
index ff62253..65be19f 100644
--- a/test/std/experimental/filesystem/class.path/path.nonmember/path.io.unicode_bug.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.nonmember/path.io.unicode_bug.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.path/path.nonmember/swap.pass.cpp b/test/std/input.output/filesystems/class.path/path.nonmember/swap.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.path/path.nonmember/swap.pass.cpp
rename to test/std/input.output/filesystems/class.path/path.nonmember/swap.pass.cpp
index 4f7b93a..554b512 100644
--- a/test/std/experimental/filesystem/class.path/path.nonmember/swap.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/path.nonmember/swap.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // void swap(path& lhs, path& rhs) noexcept;
 
diff --git a/test/std/experimental/filesystem/class.path/synop.pass.cpp b/test/std/input.output/filesystems/class.path/synop.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.path/synop.pass.cpp
rename to test/std/input.output/filesystems/class.path/synop.pass.cpp
index 3ed0a8f..875f92f 100644
--- a/test/std/experimental/filesystem/class.path/synop.pass.cpp
+++ b/test/std/input.output/filesystems/class.path/synop.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path
 
diff --git a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/copy.pass.cpp b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/copy.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/copy.pass.cpp
rename to test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/copy.pass.cpp
index 15cf505..40ce491 100644
--- a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/copy.pass.cpp
+++ b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/copy.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class recursive_directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/copy_assign.pass.cpp b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/copy_assign.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/copy_assign.pass.cpp
rename to test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/copy_assign.pass.cpp
index ebe4c87..00c8c35 100644
--- a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/copy_assign.pass.cpp
+++ b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/copy_assign.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class recursive_directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/ctor.pass.cpp b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/ctor.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/ctor.pass.cpp
rename to test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/ctor.pass.cpp
index 29a8625..e02d667 100644
--- a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/ctor.pass.cpp
+++ b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/ctor.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/depth.pass.cpp b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/depth.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/depth.pass.cpp
rename to test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/depth.pass.cpp
index d27194a..9b239c6 100644
--- a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/depth.pass.cpp
+++ b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/depth.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class recursive_directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/disable_recursion_pending.pass.cpp b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/disable_recursion_pending.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/disable_recursion_pending.pass.cpp
rename to test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/disable_recursion_pending.pass.cpp
index e385624..799494f 100644
--- a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/disable_recursion_pending.pass.cpp
+++ b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/disable_recursion_pending.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class recursive_directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/increment.pass.cpp b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/increment.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/increment.pass.cpp
rename to test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/increment.pass.cpp
index ad61518..bfc8189 100644
--- a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/increment.pass.cpp
+++ b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/increment.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class recursive_directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/move.pass.cpp b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/move.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/move.pass.cpp
rename to test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/move.pass.cpp
index 6fe26d5..e258c45 100644
--- a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/move.pass.cpp
+++ b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/move.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class recursive_directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/move_assign.pass.cpp b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/move_assign.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/move_assign.pass.cpp
rename to test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/move_assign.pass.cpp
index fc6d05c..61bb872 100644
--- a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/move_assign.pass.cpp
+++ b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/move_assign.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class recursive_directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/pop.pass.cpp b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/pop.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/pop.pass.cpp
rename to test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/pop.pass.cpp
index 39e0f4f..fe6ce5f 100644
--- a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/pop.pass.cpp
+++ b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/pop.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class recursive_directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/recursion_pending.pass.cpp b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/recursion_pending.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/recursion_pending.pass.cpp
rename to test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/recursion_pending.pass.cpp
index 36453a2..662c114 100644
--- a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.members/recursion_pending.pass.cpp
+++ b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.members/recursion_pending.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class recursive_directory_iterator
 
diff --git a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.nonmembers/begin_end.pass.cpp b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.nonmembers/begin_end.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.nonmembers/begin_end.pass.cpp
rename to test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.nonmembers/begin_end.pass.cpp
index 8d9f14d..04bc2dd 100644
--- a/test/std/experimental/filesystem/class.rec.dir.itr/rec.dir.itr.nonmembers/begin_end.pass.cpp
+++ b/test/std/input.output/filesystems/class.rec.dir.itr/rec.dir.itr.nonmembers/begin_end.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class recursive_directory_iterator
 
diff --git a/test/std/experimental/filesystem/fs.enum/check_bitmask_types.hpp b/test/std/input.output/filesystems/fs.enum/check_bitmask_types.hpp
similarity index 100%
rename from test/std/experimental/filesystem/fs.enum/check_bitmask_types.hpp
rename to test/std/input.output/filesystems/fs.enum/check_bitmask_types.hpp
diff --git a/test/std/experimental/filesystem/fs.enum/enum.copy_options.pass.cpp b/test/std/input.output/filesystems/fs.enum/enum.copy_options.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.enum/enum.copy_options.pass.cpp
rename to test/std/input.output/filesystems/fs.enum/enum.copy_options.pass.cpp
index 4e3a33c..7547730 100644
--- a/test/std/experimental/filesystem/fs.enum/enum.copy_options.pass.cpp
+++ b/test/std/input.output/filesystems/fs.enum/enum.copy_options.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // enum class copy_options;
 
diff --git a/test/std/experimental/filesystem/fs.enum/enum.directory_options.pass.cpp b/test/std/input.output/filesystems/fs.enum/enum.directory_options.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/fs.enum/enum.directory_options.pass.cpp
rename to test/std/input.output/filesystems/fs.enum/enum.directory_options.pass.cpp
index d866c0b..db40f6d 100644
--- a/test/std/experimental/filesystem/fs.enum/enum.directory_options.pass.cpp
+++ b/test/std/input.output/filesystems/fs.enum/enum.directory_options.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // enum class directory_options;
 
diff --git a/test/std/experimental/filesystem/fs.enum/enum.file_type.pass.cpp b/test/std/input.output/filesystems/fs.enum/enum.file_type.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/fs.enum/enum.file_type.pass.cpp
rename to test/std/input.output/filesystems/fs.enum/enum.file_type.pass.cpp
index 6b6e069..899ab68 100644
--- a/test/std/experimental/filesystem/fs.enum/enum.file_type.pass.cpp
+++ b/test/std/input.output/filesystems/fs.enum/enum.file_type.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // enum class file_type;
 
diff --git a/test/std/experimental/filesystem/fs.enum/enum.path.format.pass.cpp b/test/std/input.output/filesystems/fs.enum/enum.path.format.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/fs.enum/enum.path.format.pass.cpp
rename to test/std/input.output/filesystems/fs.enum/enum.path.format.pass.cpp
index 51e3f86..d4ec48e 100644
--- a/test/std/experimental/filesystem/fs.enum/enum.path.format.pass.cpp
+++ b/test/std/input.output/filesystems/fs.enum/enum.path.format.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // class path;
 // enum class format;
diff --git a/test/std/experimental/filesystem/fs.enum/enum.perm_options.pass.cpp b/test/std/input.output/filesystems/fs.enum/enum.perm_options.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/fs.enum/enum.perm_options.pass.cpp
rename to test/std/input.output/filesystems/fs.enum/enum.perm_options.pass.cpp
index c1066b6..5af5045 100644
--- a/test/std/experimental/filesystem/fs.enum/enum.perm_options.pass.cpp
+++ b/test/std/input.output/filesystems/fs.enum/enum.perm_options.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // enum class perm_options;
 
diff --git a/test/std/experimental/filesystem/fs.enum/enum.perms.pass.cpp b/test/std/input.output/filesystems/fs.enum/enum.perms.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.enum/enum.perms.pass.cpp
rename to test/std/input.output/filesystems/fs.enum/enum.perms.pass.cpp
index 7cd8f67..9f2e4e2 100644
--- a/test/std/experimental/filesystem/fs.enum/enum.perms.pass.cpp
+++ b/test/std/input.output/filesystems/fs.enum/enum.perms.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // enum class perms;
 
diff --git a/test/std/experimental/filesystem/fs.error.report/tested_elsewhere.pass.cpp b/test/std/input.output/filesystems/fs.error.report/tested_elsewhere.pass.cpp
similarity index 100%
rename from test/std/experimental/filesystem/fs.error.report/tested_elsewhere.pass.cpp
rename to test/std/input.output/filesystems/fs.error.report/tested_elsewhere.pass.cpp
diff --git a/test/std/experimental/filesystem/fs.filesystem.synopsis/file_time_type.pass.cpp b/test/std/input.output/filesystems/fs.filesystem.synopsis/file_time_type.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/fs.filesystem.synopsis/file_time_type.pass.cpp
rename to test/std/input.output/filesystems/fs.filesystem.synopsis/file_time_type.pass.cpp
index 1c25450..157083a 100644
--- a/test/std/experimental/filesystem/fs.filesystem.synopsis/file_time_type.pass.cpp
+++ b/test/std/input.output/filesystems/fs.filesystem.synopsis/file_time_type.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // typedef TrivialClock file_time_type;
 
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.absolute/absolute.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.absolute/absolute.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.absolute/absolute.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.absolute/absolute.pass.cpp
index 9b73aed..b2a5794 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.absolute/absolute.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.absolute/absolute.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // path absolute(const path& p, const path& base=current_path());
 
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.canonical/canonical.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.canonical/canonical.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.canonical/canonical.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.canonical/canonical.pass.cpp
index c9c9128..eb10d98 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.canonical/canonical.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.canonical/canonical.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // path canonical(const path& p);
 // path canonical(const path& p, error_code& ec);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.copy/copy.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.copy/copy.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.copy/copy.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.copy/copy.pass.cpp
index ce853b6..ba579d0 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.copy/copy.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.copy/copy.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // void copy(const path& from, const path& to);
 // void copy(const path& from, const path& to, error_code& ec);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.copy_file/copy_file.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.copy_file/copy_file.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.copy_file/copy_file.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.copy_file/copy_file.pass.cpp
index 5f02374..a67b431 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.copy_file/copy_file.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.copy_file/copy_file.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool copy_file(const path& from, const path& to);
 // bool copy_file(const path& from, const path& to, error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.copy_file/copy_file_large.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.copy_file/copy_file_large.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.copy_file/copy_file_large.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.copy_file/copy_file_large.pass.cpp
index 46b5f2a..61733d5 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.copy_file/copy_file_large.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.copy_file/copy_file_large.pass.cpp
@@ -10,7 +10,7 @@
 // UNSUPPORTED: c++98, c++03
 // REQUIRES: long_tests
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool copy_file(const path& from, const path& to);
 // bool copy_file(const path& from, const path& to, error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.copy_symlink/copy_symlink.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.copy_symlink/copy_symlink.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.copy_symlink/copy_symlink.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.copy_symlink/copy_symlink.pass.cpp
index 2530bc9..ee4a9ed 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.copy_symlink/copy_symlink.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.copy_symlink/copy_symlink.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // void copy_symlink(const path& existing_symlink, const path& new_symlink);
 // void copy_symlink(const path& existing_symlink, const path& new_symlink,
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.create_directories/create_directories.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.create_directories/create_directories.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.create_directories/create_directories.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.create_directories/create_directories.pass.cpp
index 8afc610..6b651df 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.create_directories/create_directories.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.create_directories/create_directories.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool create_directories(const path& p);
 // bool create_directories(const path& p, error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.create_directory/create_directory.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.create_directory/create_directory.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.create_directory/create_directory.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.create_directory/create_directory.pass.cpp
index 7885c4a..e73e21f 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.create_directory/create_directory.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.create_directory/create_directory.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool create_directory(const path& p);
 // bool create_directory(const path& p, error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.create_directory/create_directory_with_attributes.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.create_directory/create_directory_with_attributes.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.create_directory/create_directory_with_attributes.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.create_directory/create_directory_with_attributes.pass.cpp
index 2ee55fc..f013bbb 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.create_directory/create_directory_with_attributes.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.create_directory/create_directory_with_attributes.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool create_directory(const path& p, const path& attr);
 // bool create_directory(const path& p, const path& attr, error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.create_directory_symlink/create_directory_symlink.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.create_directory_symlink/create_directory_symlink.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.create_directory_symlink/create_directory_symlink.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.create_directory_symlink/create_directory_symlink.pass.cpp
index e7cba97..f1d9ff0 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.create_directory_symlink/create_directory_symlink.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.create_directory_symlink/create_directory_symlink.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // void create_directory_symlink(const path& existing_symlink, const path& new_symlink);
 // void create_directory_symlink(const path& existing_symlink, const path& new_symlink,
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.create_hard_link/create_hard_link.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.create_hard_link/create_hard_link.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.create_hard_link/create_hard_link.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.create_hard_link/create_hard_link.pass.cpp
index 7dbc705..f1ffc74 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.create_hard_link/create_hard_link.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.create_hard_link/create_hard_link.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // void create_hard_link(const path& existing_symlink, const path& new_symlink);
 // void create_hard_link(const path& existing_symlink, const path& new_symlink,
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.create_symlink/create_symlink.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.create_symlink/create_symlink.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.create_symlink/create_symlink.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.create_symlink/create_symlink.pass.cpp
index 46519ad..e69aae1 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.create_symlink/create_symlink.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.create_symlink/create_symlink.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // void create_symlink(const path& existing_symlink, const path& new_symlink);
 // void create_symlink(const path& existing_symlink, const path& new_symlink,
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.current_path/current_path.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.current_path/current_path.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.current_path/current_path.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.current_path/current_path.pass.cpp
index 82ba91c..dd3736e 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.current_path/current_path.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.current_path/current_path.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // path current_path();
 // path current_path(error_code& ec);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.equivalent/equivalent.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.equivalent/equivalent.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.equivalent/equivalent.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.equivalent/equivalent.pass.cpp
index 3381f64..392f66c 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.equivalent/equivalent.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.equivalent/equivalent.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool equivalent(path const& lhs, path const& rhs);
 // bool equivalent(path const& lhs, path const& rhs, std::error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.exists/exists.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.exists/exists.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.exists/exists.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.exists/exists.pass.cpp
index 4b6ed96..916052b 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.exists/exists.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.exists/exists.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool exists(file_status s) noexcept
 // bool exists(path const& p);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.file_size/file_size.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.file_size/file_size.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.file_size/file_size.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.file_size/file_size.pass.cpp
index c79012d..60e0042 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.file_size/file_size.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.file_size/file_size.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // uintmax_t file_size(const path& p);
 // uintmax_t file_size(const path& p, std::error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.hard_lk_ct/hard_link_count.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.hard_lk_ct/hard_link_count.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.hard_lk_ct/hard_link_count.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.hard_lk_ct/hard_link_count.pass.cpp
index f90e3f7..2e9704a 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.hard_lk_ct/hard_link_count.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.hard_lk_ct/hard_link_count.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // uintmax_t hard_link_count(const path& p);
 // uintmax_t hard_link_count(const path& p, std::error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_block_file/is_block_file.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_block_file/is_block_file.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.is_block_file/is_block_file.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.is_block_file/is_block_file.pass.cpp
index c27565e..36f1d6b 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_block_file/is_block_file.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_block_file/is_block_file.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool is_block_file(file_status s) noexcept
 // bool is_block_file(path const& p);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_char_file/is_character_file.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_char_file/is_character_file.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.is_char_file/is_character_file.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.is_char_file/is_character_file.pass.cpp
index 5468819..b0c3fe5 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_char_file/is_character_file.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_char_file/is_character_file.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool is_character_file(file_status s) noexcept
 // bool is_character_file(path const& p);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_directory/is_directory.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_directory/is_directory.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.is_directory/is_directory.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.is_directory/is_directory.pass.cpp
index 3270fcc..bb578b9 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_directory/is_directory.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_directory/is_directory.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool is_directory(file_status s) noexcept
 // bool is_directory(path const& p);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_empty/is_empty.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_empty/is_empty.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.is_empty/is_empty.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.is_empty/is_empty.pass.cpp
index ffe60a8..cd4dd17 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_empty/is_empty.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_empty/is_empty.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool is_empty(path const& p);
 // bool is_empty(path const& p, std::error_code& ec);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_fifo/is_fifo.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_fifo/is_fifo.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.is_fifo/is_fifo.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.is_fifo/is_fifo.pass.cpp
index 9c56f73..3c86dc0 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_fifo/is_fifo.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_fifo/is_fifo.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool is_fifo(file_status s) noexcept
 // bool is_fifo(path const& p);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_other/is_other.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_other/is_other.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.is_other/is_other.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.is_other/is_other.pass.cpp
index d01268a..a2134c7 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_other/is_other.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_other/is_other.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool is_other(file_status s) noexcept
 // bool is_other(path const& p);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_regular_file/is_regular_file.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_regular_file/is_regular_file.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.is_regular_file/is_regular_file.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.is_regular_file/is_regular_file.pass.cpp
index 96e027d..0c34886 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_regular_file/is_regular_file.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_regular_file/is_regular_file.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool is_regular_file(file_status s) noexcept
 // bool is_regular_file(path const& p);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_socket/is_socket.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_socket/is_socket.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.is_socket/is_socket.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.is_socket/is_socket.pass.cpp
index 1593d6a..7273c6c 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_socket/is_socket.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_socket/is_socket.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool is_socket(file_status s) noexcept
 // bool is_socket(path const& p);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_symlink/is_symlink.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_symlink/is_symlink.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.is_symlink/is_symlink.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.is_symlink/is_symlink.pass.cpp
index 97cd0a3..e1ac98a 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.is_symlink/is_symlink.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.is_symlink/is_symlink.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool is_symlink(file_status s) noexcept
 // bool is_symlink(path const& p);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp
index 616264d..bc77f3f 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // file_time_type last_write_time(const path& p);
 // file_time_type last_write_time(const path& p, std::error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.permissions/permissions.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.permissions/permissions.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.permissions/permissions.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.permissions/permissions.pass.cpp
index 65d8d71..cbe2b2d 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.permissions/permissions.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.permissions/permissions.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // void permissions(const path& p, perms prms,
 //                  perm_options opts = perm_options::replace);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.proximate/proximate.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.proximate/proximate.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.proximate/proximate.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.proximate/proximate.pass.cpp
index dc89228..5f7b30d 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.proximate/proximate.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.proximate/proximate.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // path proximate(const path& p, error_code &ec)
 // path proximate(const path& p, const path& base = current_path())
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.read_symlink/read_symlink.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.read_symlink/read_symlink.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.read_symlink/read_symlink.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.read_symlink/read_symlink.pass.cpp
index 8011da3..43dfec8 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.read_symlink/read_symlink.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.read_symlink/read_symlink.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // path read_symlink(const path& p);
 // path read_symlink(const path& p, error_code& ec);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.relative/relative.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.relative/relative.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.relative/relative.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.relative/relative.pass.cpp
index 62bc32a..e240c64 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.relative/relative.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.relative/relative.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // path proximate(const path& p, error_code &ec)
 // path proximate(const path& p, const path& base = current_path())
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.remove/remove.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.remove/remove.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.remove/remove.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.remove/remove.pass.cpp
index 2b5f52c..37b47f1 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.remove/remove.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.remove/remove.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool remove(const path& p);
 // bool remove(const path& p, error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.remove_all/remove_all.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.remove_all/remove_all.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.remove_all/remove_all.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.remove_all/remove_all.pass.cpp
index 99935f4..0f015c3 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.remove_all/remove_all.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.remove_all/remove_all.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // uintmax_t remove_all(const path& p);
 // uintmax_t remove_all(const path& p, error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.rename/rename.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.rename/rename.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.rename/rename.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.rename/rename.pass.cpp
index f20d73f..e2ebdc6 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.rename/rename.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.rename/rename.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // void rename(const path& old_p, const path& new_p);
 // void rename(const path& old_p,  const path& new_p, error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.resize_file/resize_file.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.resize_file/resize_file.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.resize_file/resize_file.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.resize_file/resize_file.pass.cpp
index 38596cd..1a2df47 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.resize_file/resize_file.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.resize_file/resize_file.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // void resize_file(const path& p, uintmax_t new_size);
 // void resize_file(const path& p, uintmax_t new_size, error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.space/space.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.space/space.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.space/space.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.space/space.pass.cpp
index 4f617cd..2c2e75a 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.space/space.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.space/space.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // space_info space(const path& p);
 // space_info space(const path& p, error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.status/status.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.status/status.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.status/status.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.status/status.pass.cpp
index 997f318..ab72f2e 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.status/status.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.status/status.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // file_status status(const path& p);
 // file_status status(const path& p, error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.status_known/status_known.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.status_known/status_known.pass.cpp
similarity index 97%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.status_known/status_known.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.status_known/status_known.pass.cpp
index ed6733f..d74ced6 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.status_known/status_known.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.status_known/status_known.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // bool status_known(file_status s) noexcept;
 
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.symlink_status/symlink_status.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.symlink_status/symlink_status.pass.cpp
similarity index 99%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.symlink_status/symlink_status.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.symlink_status/symlink_status.pass.cpp
index 9db83fb..fac630d 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.symlink_status/symlink_status.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.symlink_status/symlink_status.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // file_status symlink_status(const path& p);
 // file_status symlink_status(const path& p, error_code& ec) noexcept;
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.temp_dir_path/temp_directory_path.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.temp_dir_path/temp_directory_path.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.temp_dir_path/temp_directory_path.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.temp_dir_path/temp_directory_path.pass.cpp
index 1942bd8..523e429 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.temp_dir_path/temp_directory_path.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.temp_dir_path/temp_directory_path.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // path temp_directory_path();
 // path temp_directory_path(error_code& ec);
diff --git a/test/std/experimental/filesystem/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp b/test/std/input.output/filesystems/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp
similarity index 98%
rename from test/std/experimental/filesystem/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp
rename to test/std/input.output/filesystems/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp
index b4cb81d..0fe058f 100644
--- a/test/std/experimental/filesystem/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp
+++ b/test/std/input.output/filesystems/fs.op.funcs/fs.op.weakly_canonical/weakly_canonical.pass.cpp
@@ -9,7 +9,7 @@
 
 // UNSUPPORTED: c++98, c++03
 
-// <experimental/filesystem>
+// <filesystem>
 
 // path weakly_canonical(const path& p);
 // path weakly_canonical(const path& p, error_code& ec);
diff --git a/test/std/input.output/filesystems/fs.req.macros/feature_macro.pass.cpp b/test/std/input.output/filesystems/fs.req.macros/feature_macro.pass.cpp
new file mode 100644
index 0000000..071fa80
--- /dev/null
+++ b/test/std/input.output/filesystems/fs.req.macros/feature_macro.pass.cpp
@@ -0,0 +1,29 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// <filesystem>
+
+// #define __cpp_lib_filesystem 201703L
+
+#include <filesystem>
+#include "test_macros.h"
+
+#if TEST_STD_VER >= 17
+#ifndef __cpp_lib_filesystem
+#error Filesystem feature test macro is not defined  (__cpp_lib_filesystem)
+#elif __cpp_lib_filesystem != 201703L
+#error Filesystem feature test macro has an incorrect value (__cpp_lib_filesystem)
+#endif
+#else // TEST_STD_VER < 17
+#ifdef __cpp_lib_filesystem
+#error Filesystem feature test macro should not be defined before C++17
+#endif
+#endif
+
+int main() { }
diff --git a/test/std/input.output/filesystems/fs.req.namespace/namespace.fail.cpp b/test/std/input.output/filesystems/fs.req.namespace/namespace.fail.cpp
new file mode 100644
index 0000000..c61bb2e
--- /dev/null
+++ b/test/std/input.output/filesystems/fs.req.namespace/namespace.fail.cpp
@@ -0,0 +1,29 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// REQUIRES: c++98 || c++03 || c++11 || c++14
+
+// <filesystem>
+
+// namespace std::filesystem
+
+#include <filesystem>
+#include "test_macros.h"
+
+using namespace std::filesystem;
+
+#if TEST_STD_VER >= 11
+// expected-error@-3 {{no namespace named 'filesystem' in namespace 'std';}}
+#else
+// expected-error@-5 {{expected namespace name}}
+#endif
+
+int main() {
+
+}
diff --git a/test/std/input.output/filesystems/fs.req.namespace/namespace.pass.cpp b/test/std/input.output/filesystems/fs.req.namespace/namespace.pass.cpp
new file mode 100644
index 0000000..557de34
--- /dev/null
+++ b/test/std/input.output/filesystems/fs.req.namespace/namespace.pass.cpp
@@ -0,0 +1,26 @@
+//===----------------------------------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+// UNSUPPORTED: c++98, c++03, c++11, c++14
+
+// <filesystem>
+
+// namespace std::filesystem
+
+#include <filesystem>
+#include <type_traits>
+
+using namespace std::filesystem;
+
+int main() {
+  static_assert(std::is_same<
+          path,
+          std::filesystem::path
+      >::value, "");
+}
diff --git a/test/std/experimental/filesystem/lit.local.cfg b/test/std/input.output/filesystems/lit.local.cfg
similarity index 100%
rename from test/std/experimental/filesystem/lit.local.cfg
rename to test/std/input.output/filesystems/lit.local.cfg
diff --git a/test/support/filesystem_include.hpp b/test/support/filesystem_include.hpp
index 228e710..731532a 100644
--- a/test/support/filesystem_include.hpp
+++ b/test/support/filesystem_include.hpp
@@ -1,18 +1,13 @@
 #ifndef TEST_SUPPORT_FILESYSTEM_INCLUDE_HPP
 #define TEST_SUPPORT_FILESYSTEM_INCLUDE_HPP
 
-#include <ciso646>
-// Test against std::filesystem for STL's other than libc++
-#ifndef _LIBCPP_VERSION
-#define TEST_INCLUDE_STD_FILESYSTEM
-#endif
-
-#ifdef TEST_INCLUDE_STD_FILESYSTEM
 #include <filesystem>
-namespace fs = std::filesystem;
+#include "test_macros.h"
+
+#if defined(_LIBCPP_VERSION) && TEST_STD_VER < 17
+namespace fs = std::__fs::filesystem;
 #else
-#include <experimental/filesystem>
-namespace fs = std::experimental::filesystem;
+namespace fs = std::filesystem;
 #endif
 
 #endif
diff --git a/utils/libcxx/test/config.py b/utils/libcxx/test/config.py
index 34753be..6542ceb 100644
--- a/utils/libcxx/test/config.py
+++ b/utils/libcxx/test/config.py
@@ -720,13 +720,9 @@
         enable_fs = self.get_lit_bool('enable_filesystem', default=False)
         if not enable_fs:
             return
-        enable_experimental = self.get_lit_bool('enable_experimental', default=False)
-        if not enable_experimental:
-            self.lit_config.fatal(
-                'filesystem is enabled but libc++experimental.a is not.')
         self.config.available_features.add('c++filesystem')
         static_env = os.path.join(self.libcxx_src_root, 'test', 'std',
-                                  'experimental', 'filesystem', 'Inputs', 'static_test_env')
+                                  'input.output', 'filesystems', 'Inputs', 'static_test_env')
         static_env = os.path.realpath(static_env)
         assert os.path.isdir(static_env)
         self.cxx.compile_flags += ['-DLIBCXX_FILESYSTEM_STATIC_TEST_ROOT="%s"' % static_env]
@@ -821,6 +817,10 @@
         if libcxx_experimental:
             self.config.available_features.add('c++experimental')
             self.cxx.link_flags += ['-lc++experimental']
+        libcxx_fs = self.get_lit_bool('enable_filesystem', default=False)
+        if libcxx_fs:
+            self.config.available_features.add('c++fs')
+            self.cxx.link_flags += ['-lc++fs']
         if self.link_shared:
             self.cxx.link_flags += ['-lc++']
         else:
diff --git a/www/cxx1z_status.html b/www/cxx1z_status.html
index 3d826ac..de8caa8 100644
--- a/www/cxx1z_status.html
+++ b/www/cxx1z_status.html
@@ -83,7 +83,7 @@
   	<tr><td></td><td></td><td></td><td></td><td></td><td></td></tr>
 	<tr><td><a href="https://wg21.link/P0024R2">P0024R2</a></td><td>LWG</td><td>The Parallelism TS Should be Standardized</td><td>Jacksonville</td><td></td><td></td></tr>
 	<tr><td><a href="https://wg21.link/P0226R1">P0226R1</a></td><td>LWG</td><td>Mathematical Special Functions for C++17</td><td>Jacksonville</td><td></td><td></td></tr>
-	<tr><td><a href="https://wg21.link/P0220R1">P0220R1</a></td><td>LWG</td><td>Adopt Library Fundamentals V1 TS Components for C++17</td><td>Jacksonville</td><td>In Progress</td><td></td></tr>
+	<tr><td><a href="https://wg21.link/P0220R1">P0220R1</a></td><td>LWG</td><td>Adopt Library Fundamentals V1 TS Components for C++17</td><td>Jacksonville</td><td>Complete</td><td>7.0</td></tr>
 	<tr><td><a href="https://wg21.link/P0218R1">P0218R1</a></td><td>LWG</td><td>Adopt the File System TS for C++17</td><td>Jacksonville</td><td>In Progress</td><td></td></tr>
 	<tr><td><a href="https://wg21.link/P0033R1">P0033R1</a></td><td>LWG</td><td>Re-enabling shared_from_this</td><td>Jacksonville</td><td>Complete</td><td>3.9</td></tr>
 	<tr><td><a href="https://wg21.link/P0005R4">P0005R4</a></td><td>LWG</td><td>Adopt not_fn from Library Fundamentals 2 for C++17</td><td>Jacksonville</td><td>Complete</td><td>3.9</td></tr>
@@ -443,7 +443,7 @@
 	<tr><td><a href="https://wg21.link/LWG2778">2778</a></td><td>basic_string_view is missing constexpr</td><td>Issaquah</td><td>Complete</td></tr>
  	<tr><td></td><td></td><td></td><td></td></tr>
 	<tr><td><a href="https://wg21.link/LWG2260">2260</a></td><td>Missing requirement for Allocator::pointer</td><td>Kona</td><td></td></tr>
-	<tr><td><a href="https://wg21.link/LWG2676">2676</a></td><td>Provide filesystem::path overloads for File-based streams</td><td>Kona</td><td></td></tr>
+	<tr><td><a href="https://wg21.link/LWG2676">2676</a></td><td>Provide filesystem::path overloads for File-based streams</td><td>Kona</td><td>Complete</td></tr>
 	<tr><td><a href="https://wg21.link/LWG2768">2768</a></td><td>any_cast and move semantics</td><td>Kona</td><td>Complete</td></tr>
 	<tr><td><a href="https://wg21.link/LWG2769">2769</a></td><td>Redundant const in the return type of any_cast(const any&amp;)</td><td>Kona</td><td>Complete</td></tr>
 	<tr><td><a href="https://wg21.link/LWG2781">2781</a></td><td>Contradictory requirements for std::function and std::reference_wrapper</td><td>Kona</td><td>Complete</td></tr>