gistfile1.kt

interface A {
    fun f(x : Int) {}
}

interface B<T> : A {
    fun f(y: T)
}

interface C : B<Int>

fun foo(b : B<Int>, c : C)  {
    b.f(x = 1) // OK
    b.f(y = 1) // OK
    b.f(1) // Error: Overload resolution ambiguity


    c.f(x = 1) // Error: Cannot find a parameter with this name: x
    c.f(y = 1) // OK
    c.f(1) // OK
}