Add tests to ensure that string_view|ref from rvalue fails (whenever it can)

test/string_ref_from_rvalue.cpp

@@ -0,0 +1,28 @@
+/*
+   Copyright (c) Marshall Clow 2017.
+
+   Distributed under the Boost Software License, Version 1.0. (See accompanying
+   file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+    For more information, see http://www.boost.org
+*/
+
+#include <iostream>
+#include <algorithm>
+#include <string>
+
+#include <boost/utility/string_ref.hpp>
+
+#if defined(BOOST_NO_CXX11_RVALUE_REFERENCES) || defined(BOOST_NO_CXX11_DELETED_FUNCTIONS)
+#error "Unsupported test"
+#endif
+
+#include "boost/test/minimal.hpp"
+
+std::string makeatemp() { return "abc"; }
+
+int test_main(int, char **)
+{
+  boost::basic_string_ref<char> sv(makeatemp());
+  return 0;
+}