==== tests/cases/compiler/assignmentStricterConstraints.ts (2 errors) ====
    var f = function <T, S extends T>(x: T, y: S): void {
                         ~~~~~~~~~~~
!!! Constraint of a type parameter cannot reference any type parameter from the same type parameter list.
        x = y
        ~
!!! Type 'S' is not assignable to type 'T'.
    }
    
    var g = function <T, S>(x: T, y: S): void { }
    
    g = f
    g(1, "")