When the variable declaration does not have an initializer, and it is assigned, CC0009 is incorrectly triggered. This should not raise a diagnostic for CC0009:

class Foo
{
    public Foo F { get; set; }
    static void Baz()
    {
        Foo foo;
        foo = new Foo();
        foo.F = foo;
    }
}

We should check for that specific scenario.

This should still raise a diagnostic:

class Foo
{
    public Foo F { get; set; }
    static void Baz()
    {
        Foo foo;
        foo = Whatever();
        foo = new Foo();
        foo.F = foo;
    }
}

When there is a prior assignment between the variable declaration and it's assignment (or the variable being passed as ref or out to a method) CC0009 should still be raised.

This is a bug on the analyzer, not on the code fix provider.