Imported Upstream version 3.8.0

Former-commit-id: 6a76a29bd07d86e57c6c8da45c65ed5447d38a61

mcs/errors/cs0591-4.cs

@@ -0,0 +1,15 @@
+// CS0591: Invalid value for argument to `System.Runtime.InteropServices.DllImportAttribute' attribute
+// Line: 8
+
+using System.Runtime.InteropServices;
+using System;
+
+class X {
+	[DllImport (null)]
+	extern static void Blah ();
+
+    static void Main (string [] args)
+    {
+    }
+
+}