This code does not compile:

interface I {
    void m();
}
interface I1 extends I {}
interface I2 extends I {}

static void n(I1 i1, I2 i2, int s) {
    var i_ = switch (s) { //<- Object
        case 1 -> i1;
        case 2 -> null;
        default -> i2;
    };
    if (i_ != null) {
        i_.m(); //cannot find symbol m()
    }
}

Javac infers Object instead of I, suggesting some issues around handling of `null` in switch expression.