Let's consider following example:

class Clazz2 {
    private static class A {};
    public A a;
}

public class Test2 {
    static class FooNest<Q> {
        FooNest(Q q, Foo<Q> foo) { }
    }

    static class Foo<T> { }

    static Clazz2 clazz = new Clazz2();

    public static void test() {
        FooNest fooNest = new FooNest<>(clazz.a, new Foo<>() {});
    }
}

When it's compiled by JDK9b66 following messages are produced:

Error:(16, 17) java: Clazz2.A has private access in Clazz2
Error:(16, 50) java: incompatible types: <anonymous Test2.Foo<Clazz2.A>> cannot be converted to Test2.FooNest

The second message seem not to correspond to the code.

The error doesn't occur, provided assignment is removed, that is resulting in following code:

        new FooNest<>(clazz.a, new Foo<>() {});