t5426.scala:2: warning: comparing values of types Some[Int] and Int using `==' will always yield false
  def f1 = Some(5) == 5
                   ^
t5426.scala:3: warning: comparing values of types Int and Some[Int] using `==' will always yield false
  def f2 = 5 == Some(5)
             ^
t5426.scala:8: warning: comparing values of types Int and Some[Int] using `==' will always yield false
  (x1 == x2)
      ^
t5426.scala:9: warning: comparing values of types Some[Int] and Int using `==' will always yield false
  (x2 == x1)
      ^
error: No warnings can be incurred under -Xfatal-warnings.
four warnings found
one error found