Index: include/experimental/ratio
===================================================================
--- /dev/null
+++ include/experimental/ratio
@@ -0,0 +1,77 @@
+// -*- C++ -*-
+//===------------------------------ ratio ---------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_EXPERIMENTAL_RATIO
+#define _LIBCPP_EXPERIMENTAL_RATIO
+
+/**
+    experimental/ratio synopsis
+    C++1y
+#include <ratio>
+
+namespace std {
+namespace experimental {
+inline namespace fundamentals_v1 {
+
+  // See C++14 20.11.5, ratio comparison
+  template <class R1, class R2> constexpr bool ratio_equal_v
+    = ratio_equal<R1, R2>::value;
+  template <class R1, class R2> constexpr bool ratio_not_equal_v
+    = ratio_not_equal<R1, R2>::value;
+  template <class R1, class R2> constexpr bool ratio_less_v
+    = ratio_less<R1, R2>::value;
+  template <class R1, class R2> constexpr bool ratio_less_equal_v
+    = ratio_less_equal<R1, R2>::value;
+  template <class R1, class R2> constexpr bool ratio_greater_v
+    = ratio_greater<R1, R2>::value;
+  template <class R1, class R2> constexpr bool ratio_greater_equal_v
+    = ratio_greater_equal<R1, R2>::value;
+
+} // namespace fundamentals_v1
+} // namespace experimental
+} // namespace std
+
+*/
+
+#include <experimental/__config>
+
+#if _LIBCPP_STD_VER > 11
+
+#include <ratio>
+
+_LIBCPP_BEGIN_NAMESPACE_LFTS
+
+#if __has_feature(cxx_variable_templates)
+
+template <class _R1, class _R2> _LIBCPP_CONSTEXPR bool ratio_equal_v
+    = ratio_equal<_R1, _R2>::value;
+
+template <class _R1, class _R2> _LIBCPP_CONSTEXPR bool ratio_not_equal_v
+    = ratio_not_equal<_R1, _R2>::value;
+
+template <class _R1, class _R2> _LIBCPP_CONSTEXPR bool ratio_less_v
+    = ratio_less<_R1, _R2>::value;
+
+template <class _R1, class _R2> _LIBCPP_CONSTEXPR bool ratio_less_equal_v
+    = ratio_less_equal<_R1, _R2>::value;
+
+template <class _R1, class _R2> _LIBCPP_CONSTEXPR bool ratio_greater_v
+    = ratio_greater<_R1, _R2>::value;
+
+template <class _R1, class _R2> _LIBCPP_CONSTEXPR bool ratio_greater_equal_v
+    = ratio_greater_equal<_R1, _R2>::value;
+
+#endif /* __has_feature(cxx_variable_templates) */
+
+_LIBCPP_END_NAMESPACE_LFTS
+
+#endif /* _LIBCPP_STD_VER > 11 */
+
+#endif _LIBCPP_EXPERIMENTAL_RATIO
\ No newline at end of file
Index: test/libcxx/experimental/utilities/ratio/header.ratio.synop/includes.pass.cpp
===================================================================
--- /dev/null
+++ test/libcxx/experimental/utilities/ratio/header.ratio.synop/includes.pass.cpp
@@ -0,0 +1,24 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <experimental/ratio>
+
+// Test that <ratio> is included.
+
+#include <experimental/ratio>
+
+#ifndef _LIBCPP_STD_VER > 11
+# ifndef _LIBCPP_RATIO
+#   error " <experimental/ratio> must include <ratio>"
+# endif
+#endif
+
+int main()
+{
+}
Index: test/libcxx/experimental/utilities/ratio/version.pass.cpp
===================================================================
--- /dev/null
+++ test/libcxx/experimental/utilities/ratio/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.
+//
+//===----------------------------------------------------------------------===//
+
+// <experimental/ratio>
+
+#include <experimental/ratio>
+
+#ifndef _LIBCPP_VERSION
+#error _LIBCPP_VERSION not defined
+#endif
+
+int main()
+{
+}
Index: test/std/experimental/utilities/ratio/header.ratio.synop/includes.pass.cpp
===================================================================
--- /dev/null
+++ test/std/experimental/utilities/ratio/header.ratio.synop/includes.pass.cpp
@@ -0,0 +1,21 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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
+
+// <experimental/ratio>
+
+// Test that <ratio> is included.
+
+#include <experimental/ratio>
+
+int main()
+{
+  std::ratio<100> x;
+}
Index: test/std/experimental/utilities/ratio/header.ratio.synop/ratio_equal_v.pass.cpp
===================================================================
--- /dev/null
+++ test/std/experimental/utilities/ratio/header.ratio.synop/ratio_equal_v.pass.cpp
@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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
+
+// <experimental/ratio>
+
+// template <class R1, class R2> constexpr bool ratio_equal_v;
+
+#include <experimental/ratio>
+#include <type_traits>
+
+namespace ex = std::experimental;
+
+int main()
+{
+    {
+        typedef std::ratio<1, 1> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            ex::ratio_equal_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_equal_v<R1, R2> == std::ratio_equal<R1, R2>::value, ""
+          );
+        static_assert(
+            std::is_same<decltype(ex::ratio_equal_v<R1, R2>), const bool>::value
+          , ""
+          );
+    }
+    {
+        typedef std::ratio<1, 1> R1;
+        typedef std::ratio<1, -1> R2;
+        static_assert(
+            !ex::ratio_equal_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_equal_v<R1, R2> == std::ratio_equal<R1, R2>::value, ""
+          );
+    }
+}
Index: test/std/experimental/utilities/ratio/header.ratio.synop/ratio_greater_equal_v.pass.cpp
===================================================================
--- /dev/null
+++ test/std/experimental/utilities/ratio/header.ratio.synop/ratio_greater_equal_v.pass.cpp
@@ -0,0 +1,61 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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
+
+// <experimental/ratio>
+
+// template <class R1, class R2> constexpr bool ratio_greater_equal_v;
+
+#include <experimental/ratio>
+#include <type_traits>
+
+namespace ex = std::experimental;
+
+int main()
+{
+    {
+        typedef std::ratio<1, 2> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            !ex::ratio_greater_equal_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_greater_equal_v<R1, R2>
+            == std::ratio_greater_equal<R1, R2>::value, ""
+          );
+        static_assert(
+            std::is_same<
+              decltype(ex::ratio_greater_equal_v<R1, R2>), const bool>::value
+          , ""
+          );
+    }
+    {
+        typedef std::ratio<1, 1> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            ex::ratio_greater_equal_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_greater_equal_v<R1, R2>
+            == std::ratio_greater_equal<R1, R2>::value, ""
+          );
+    }
+    {
+        typedef std::ratio<2, 1> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            ex::ratio_greater_equal_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_greater_equal_v<R1, R2>
+            == std::ratio_greater_equal<R1, R2>::value, ""
+          );
+    }
+}
Index: test/std/experimental/utilities/ratio/header.ratio.synop/ratio_greater_v.pass.cpp
===================================================================
--- /dev/null
+++ test/std/experimental/utilities/ratio/header.ratio.synop/ratio_greater_v.pass.cpp
@@ -0,0 +1,57 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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
+
+// <experimental/ratio>
+
+// template <class R1, class R2> constexpr bool ratio_greater_v;
+
+#include <experimental/ratio>
+#include <type_traits>
+
+namespace ex = std::experimental;
+
+int main()
+{
+    {
+        typedef std::ratio<1, 2> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            !ex::ratio_greater_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_greater_v<R1, R2> == std::ratio_greater<R1, R2>::value, ""
+          );
+        static_assert(
+            std::is_same<decltype(ex::ratio_greater_v<R1, R2>), const bool>::value
+          , ""
+          );
+    }
+    {
+        typedef std::ratio<1, 1> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            !ex::ratio_greater_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_greater_v<R1, R2> == std::ratio_greater<R1, R2>::value, ""
+          );
+    }
+    {
+        typedef std::ratio<2, 1> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            ex::ratio_greater_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_greater_v<R1, R2> == std::ratio_greater<R1, R2>::value, ""
+          );
+    }
+}
Index: test/std/experimental/utilities/ratio/header.ratio.synop/ratio_less_equal_v.pass.cpp
===================================================================
--- /dev/null
+++ test/std/experimental/utilities/ratio/header.ratio.synop/ratio_less_equal_v.pass.cpp
@@ -0,0 +1,57 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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
+
+// <experimental/ratio>
+
+// template <class R1, class R2> constexpr bool ratio_less_equal_v;
+
+#include <experimental/ratio>
+#include <type_traits>
+
+namespace ex = std::experimental;
+
+int main()
+{
+    {
+        typedef std::ratio<1, 2> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            ex::ratio_less_equal_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_less_equal_v<R1, R2> == std::ratio_less_equal<R1, R2>::value, ""
+          );
+        static_assert(
+            std::is_same<decltype(ex::ratio_less_equal_v<R1, R2>), const bool>::value
+          , ""
+          );
+    }
+    {
+        typedef std::ratio<1, 1> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            ex::ratio_less_equal_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_less_equal_v<R1, R2> == std::ratio_less_equal<R1, R2>::value, ""
+          );
+    }
+    {
+        typedef std::ratio<2, 1> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            !ex::ratio_less_equal_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_less_equal_v<R1, R2> == std::ratio_less_equal<R1, R2>::value, ""
+          );
+    }
+}
Index: test/std/experimental/utilities/ratio/header.ratio.synop/ratio_less_v.pass.cpp
===================================================================
--- /dev/null
+++ test/std/experimental/utilities/ratio/header.ratio.synop/ratio_less_v.pass.cpp
@@ -0,0 +1,57 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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
+
+// <experimental/ratio>
+
+// template <class R1, class R2> constexpr bool ratio_less_v;
+
+#include <experimental/ratio>
+#include <type_traits>
+
+namespace ex = std::experimental;
+
+int main()
+{
+    {
+        typedef std::ratio<1, 2> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            ex::ratio_less_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_less_v<R1, R2> == std::ratio_less<R1, R2>::value, ""
+          );
+        static_assert(
+            std::is_same<decltype(ex::ratio_less_v<R1, R2>), const bool>::value
+          , ""
+          );
+    }
+    {
+        typedef std::ratio<1, 1> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            !ex::ratio_less_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_less_v<R1, R2> == std::ratio_less<R1, R2>::value, ""
+          );
+    }
+    {
+        typedef std::ratio<2, 1> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            !ex::ratio_less_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_less_v<R1, R2> == std::ratio_less<R1, R2>::value, ""
+          );
+    }
+}
Index: test/std/experimental/utilities/ratio/header.ratio.synop/ratio_not_equal_v.pass.cpp
===================================================================
--- /dev/null
+++ test/std/experimental/utilities/ratio/header.ratio.synop/ratio_not_equal_v.pass.cpp
@@ -0,0 +1,47 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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
+
+// <experimental/ratio>
+
+// template <class R1, class R2> constexpr bool ratio_not_equal_v;
+
+#include <experimental/ratio>
+#include <type_traits>
+
+namespace ex = std::experimental;
+
+int main()
+{
+    {
+        typedef std::ratio<1, 1> R1;
+        typedef std::ratio<1, -1> R2;
+        static_assert(
+            ex::ratio_not_equal_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_not_equal_v<R1, R2> == std::ratio_not_equal<R1, R2>::value, ""
+          );
+        static_assert(
+            std::is_same<decltype(ex::ratio_not_equal_v<R1, R2>), const bool>::value
+          , ""
+          );
+    }
+    {
+        typedef std::ratio<1, 1> R1;
+        typedef std::ratio<1, 1> R2;
+        static_assert(
+            !ex::ratio_not_equal_v<R1, R2>, ""
+          );
+        static_assert(
+            ex::ratio_not_equal_v<R1, R2> == std::ratio_not_equal<R1, R2>::value, ""
+          );
+    }
+}
Index: test/std/experimental/utilities/ratio/nothing_to_do.pass.cpp
===================================================================
--- /dev/null
+++ test/std/experimental/utilities/ratio/nothing_to_do.pass.cpp
@@ -0,0 +1,13 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+int main()
+{
+}