Implement P0754R2: The <version> header.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@329075 91177308-0d34-0410-b5e6-96231b3b80d8

include/version

@@ -0,0 +1,25 @@
+// -*- C++ -*-
+//===--------------------------- version ----------------------------------===//
+//
+//                     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_VERSIONH
+#define _LIBCPP_VERSIONH
+
+/*
+    version synopsis
+
+*/
+
+#include <__config>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+#endif  // _LIBCPP_VERSIONH

test/libcxx/language.support/support.limits/version.pass.cpp

@@ -0,0 +1,23 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <version>
+// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
+// UNSUPPORTED: clang-3.3, clang-3.4, clang-3.5, clang-3.6, clang-3.7
+// UNSUPPORTED: clang-3.8, clang-3.9, clang-4.0, clang-5.0, clang-6.0
+
+#include <version>
+
+#if !defined(_LIBCPP_VERSION)
+#error "_LIBCPP_VERSION must be defined after including <version>"
+#endif
+
+int main()
+{
+}

test/std/language.support/support.limits/version.pass.cpp

@@ -0,0 +1,17 @@
+//===----------------------------------------------------------------------===//
+//
+//                     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.
+//
+//===----------------------------------------------------------------------===//
+
+// <version>
+// UNSUPPORTED: c++98, c++03, c++11, c++14, c++17
+
+#include <version>
+
+int main()
+{
+}

www/cxx2a_status.html

@@ -76,7 +76,7 @@
 	<tr><td><a href="https://wg21.link/P0355R7">P0355R7</a></td><td>LWG</td><td>Extending chrono to Calendars and Time Zones</td><td>Jacksonville</td><td></td><td></td></tr>
 	<tr><td><a href="https://wg21.link/P0551R3">P0551R3</a></td><td>LWG</td><td>Thou Shalt Not Specialize <tt>std</tt> Function Templates!</td><td>Jacksonville</td><td></td><td></td></tr>
 	<tr><td><a href="https://wg21.link/P0753R2">P0753R2</a></td><td>LWG</td><td>Manipulators for C++ Synchronized Buffered Ostream</td><td>Jacksonville</td><td></td><td></td></tr>
-	<tr><td><a href="https://wg21.link/P0754R2">P0754R2</a></td><td>LWG</td><td>&lt;version&gt;</td><td>Jacksonville</td><td></td><td></td></tr>
+	<tr><td><a href="https://wg21.link/P0754R2">P0754R2</a></td><td>LWG</td><td>&lt;version&gt;</td><td>Jacksonville</td><td>Complete</td><td>7.0</td></tr>
 	<tr><td><a href="https://wg21.link/P0809R0">P0809R0</a></td><td>LWG</td><td>Comparing Unordered Containers</td><td>Jacksonville</td><td></td><td></td></tr>
 	<tr><td><a href="https://wg21.link/P0858R0">P0858R0</a></td><td>LWG</td><td>Constexpr iterator requirements</td><td>Jacksonville</td><td></td><td></td></tr>
 	<tr><td><a href="https://wg21.link/P0905R1">P0905R1</a></td><td>CWG</td><td>Symmetry for spaceship</td><td>Jacksonville</td><td></td><td></td></tr>
@@ -180,7 +180,7 @@
 <!-- 	<tr><td></td><td></td><td></td><td></td></tr> -->
   </table>
 
-  <p>Last Updated: 20-Mar-2018</p>
+  <p>Last Updated: 3-Apr-2018</p>
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