Consider the following:

Outer.java

package pack;

class Outer {
  enum Inner {
    CONST
  }
  Outer(Inner inner) {
  }
}

Other.groovy

package pack

class Other extends Outer {
  Other() {
    super(Inner.CONST)
  }
}

Unqualified reference "Inner" in the Groovy source has marker "Apparent variable 'Inner' was found in a static scope but doesn't refer to a local variable, static field or class." This use case works under groovyc.