t6902.scala:4: warning: unreachable code
    case Some(b) => 3 // no warning was emitted
                    ^
t6902.scala:9: warning: unreachable code
    case Some(b) => 3 // no warning was emitted
                    ^
t6902.scala:21: warning: unreachable code
    case 1 => 3 // crash
              ^
error: No warnings can be incurred under -Xfatal-warnings.
three warnings found
one error found