constexpr.cc: Add.

2011-08-29  Benjamin Kosnik  <bkoz@redhat.com>

	* testsuite/20_util/duration/arithmetic/constexpr.cc: Add.

From-SVN: r178265

libstdc++-v3/ChangeLog

+2011-08-29  Benjamin Kosnik  <bkoz@redhat.com>
+
+	* testsuite/20_util/duration/arithmetic/constexpr.cc: Add.
+
 2011-08-29  Kai Tietz  <ktietz@redhat.com>
 
 	* configure: Regenerated.

libstdc++-v3/testsuite/20_util/duration/arithmetic/constexpr.cc

+// { dg-do compile }
+// { dg-options "-std=gnu++0x" }
+
+// Copyright (C) 2011 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library.  This library is free
+// software; you can redistribute it and/or modify it under the
+// terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 3, or (at your option)
+// any later version.
+
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License along
+// with this library; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <chrono>
+#include <testsuite_common_types.h>
+
+int main()
+{
+  constexpr std::chrono::nanoseconds d1 { };
+  constexpr auto d2(+d1);
+  constexpr auto d3(-d2);
+  return 0;
+}