t4137.scala:9: error: overriding type EPC in trait A, which equals [X1]C[X1];
 type EPC has incompatible type
  override type EPC = C[T]
                ^
t4137.scala:10: error: overriding type EPC2 in trait A, which equals [X1]C[X1];
 type EPC2 has incompatible type
  override type EPC2[X1 <: String] = C[X1]
                ^
two errors found