// CS0452: The type `int' must be a reference type in order to use it as type parameter `T' in the generic type or method `A.Foo(T, string)' // Line: 18 class A { static int Foo (T a, string s) where T : class { return 1; } static int Foo (T a, object y) { return 2; } public static void Main () { A.Foo (99, null); } }