While attributing this test case:

class Test {

    interface Function<X, Y> {
        Y m(X x);
    }

    interface Box<T> {
        T get();
        <R> R map(Function<T,R> f);
    }

    static class Person {
        Person(String name) { }
    }

    void print(Object arg) { }
    void print(String arg) { }

    void test() {
        Box<String> b = null;
        print(b.map(s -> new Person(s)));
    }
}

javac "unsticks" the implicit lambda during overload resolution, thus selecting method print(Object) as applicable. This is incorrect, method print(String) should be the one selected.