Consider module-info like:

    module m {
        provides test.Service with test.Provider;
    }

And assume test.Provider does not exist in the sources, but is generated by an annotation processor. This works, unless the AP lists the directives from the module, in which case it fails:

testGenerateServiceImplementation/src/module-info.java:3: error: the service implementation does not have a default constructor: Provider
    provides test.Service with test.Provider;
                                   ^