kotlin-fork/idea/testData/checker/regression/Jet183.kt

// FIR_COMPARISON

enum class ProtocolState {
  WAITING {
    override fun signal() = ProtocolState.TALKING
  },

  TALKING {
    override fun signal() = ProtocolState.WAITING
  };

  abstract fun signal() : ProtocolState
}

fun box() {
   val <warning>x</warning>: ProtocolState = ProtocolState.WAITING
}