(Reporting this for reference, to have an issue number. I have a fix already.)

Reported on scala-internals by Georgi Jojgov.

class A[@specialized(Int) T](val value: T) {
  trait B
  def useValue(x:T): Unit = ()
  useValue(value)
}

produces a warning: Class A$B differs only in case from A$B.

The reason is that the trait B is moved into the primary constructor by Constructors, and then copied into the constructor of the specialized subclass. So the class is generated twice in the backend.