'impossible' compile time error, when using `runStream'.

ghc: panic! (the 'impossible' happened)
  (GHC version 7.0.3 for i386-unknown-linux):
	addTickHsExpr
    (|/\(@ a{tv aZE} [sk]).
      (arrows-0.4.4.0:Control.Arrow.Transformer.Stream.runStream{v rfV} [gid])
      @ t{tv aZY} [sk]
      @ a{tv aZE} [sk]
      @ t{tv a102} [sk]
      @ t{tv aZZ} [sk]
        $dArrowLoop{v aZF} [lid]
        ((\ ((x{v aZc} [lid] :: t{tv a102} [sk]))
            -> {49:30-52}
               ((base:Control.Arrow.loop{v 020} [gid[ClassOp]])
                @ (arrows-0.4.4.0:Control.Arrow.Transformer.Stream.StreamArrow{tc rgp}
                     t{tv aZY} [sk])
                  $dArrowLoop{v aZG} [lid])
               @ (t{tv a101} [sk], t{tv a102} [sk])
               @ d{tv a100} [sk]
               @ t{tv aZZ} [sk]
                 (((base:Control.Arrow.arr{v 01V} [gid[ClassOp]])
                   @ (arrows-0.4.4.0:Control.Arrow.Transformer.Stream.StreamArrow{tc rgp}
                        t{tv aZY} [sk])
                     $dArrow{v aZI} [lid])
                  @ ((t{tv a101} [sk], t{tv a102} [sk]), d{tv a100} [sk])
                  @ (t{tv aZZ} [sk], d{tv a100} [sk])
                    k{v aZ9} [lid]) -< (s0{v aZa} [lid], x{v aZc} [lid])))|)

Please report this as a GHC bug:  http://www.haskell.org/ghc/reportabug