==== tests/cases/compiler/primitiveConstraints1.ts (2 errors) ====
    function foo1<T extends U, U>(t: T, u: U) { }
                  ~~~~~~~~~~~
!!! Constraint of a type parameter cannot reference any type parameter from the same type parameter list.
    foo1<string, number>('hm', 1); // no error
     
    function foo2<T, U extends T>(t: T, u: U) { }
                     ~~~~~~~~~~~
!!! Constraint of a type parameter cannot reference any type parameter from the same type parameter list.
    foo2<number, string>(1, 'hm'); // error