compile-file cases added to the test suite

[SVN r17029]

test/optional_test_fail4.cpp

@@ -0,0 +1,29 @@
+// (C) 2003, Fernando Luis Cacciola Carballal.
+//
+// This material is provided "as is", with absolutely no warranty expressed
+// or implied. Any use is at your own risk.
+//
+// Permission to use or copy this software for any purpose is hereby granted
+// without fee, provided the above notices are retained on all copies.
+// Permission to modify the code and to distribute modified code is granted,
+// provided the above notices are retained, and a notice that the code was
+// modified is included with the above copyright notice.
+//
+// You are welcome to contact the author at:
+//  fernando_cacciola@hotmail.com
+//
+#include "boost/optional.hpp"
+
+//
+// THIS TEST SHOULD FAIL TO COMPILE
+//
+void test_no_implicit_conversion()
+{
+  boost::optional<int> opt(1) ;
+
+  // You can compare against 0 or against another optional<>,
+  // but not against another value
+  if ( opt == 1 ) ;
+}
+
+