crash when interpreting

when I interpret my file Utilities/ChoiceMonad.hs from ghci-haskline I get the following message:

[2 of 2][Compiling Utilities.ChoiceMonad ( Utilities/ChoiceMonad.hs, interpreted )
ghci-haskeline: panic! (the 'impossible' happened)
  (GHC version 6.10.1 for i386-unknown-linux):
	ByteCodeGen.schemeE: unhandled case
    \ (@ a1{tv a1qQ} [sk] :: ghc-prim:GHC.Prim.*{(w) tc 34d})
      (@ b1{tv a1qR} [sk] :: ghc-prim:GHC.Prim.*{(w) tc 34d}) ->
      case {tick (main:Utilities.ChoiceMonad, 169)}{v d1z7} [gid]
             @ (ghc-prim:GHC.Prim.State#{(w) tc 32q}
                  ghc-prim:GHC.Prim.RealWorld{(w) tc 31E})
      {(a1{tv a1qQ} [sk] -> b1{tv a1qR} [sk])
       -> main:Utilities.ChoiceMonad.ChoiceT{tc rJw}
            m{tv aQH} [sk] a1{tv a1qQ} [sk]
       -> main:Utilities.ChoiceMonad.ChoiceT{tc rJw}
            m{tv aQH} [sk] b1{tv a1qR} [sk]}
      of (tick{v s29j} [lid] :: ghc-prim:GHC.Prim.State#{(w) tc 32q}
                                  ghc-prim:GHC.Prim.RealWorld{(w) tc 31E})
      { __DEFAULT ->
      let {
        sat_s20H{v} [lid] :: (a1{tv a1qQ} [sk] -> b1{tv a1qR} [sk])
                             -> main:Utilities.LeafyTree.LeafyTree{tc rfw} a1{tv a1qQ} [sk]
                             -> main:Utilities.LeafyTree.LeafyTree{tc rfw} b1{tv a1qR} [sk]
        []
        sat_s20H{v} [lid] =
          base:GHC.Base.fmap{v r5G} [gid]
            @ main:Utilities.LeafyTree.LeafyTree{tc rfw}
            main:Utilities.LeafyTree.$f4{v rfq} [gid]
            @ a1{tv a1qQ} [sk]
            @ b1{tv a1qR} [sk] } in
      let {
        sat_s20F{v} [lid] :: (main:Utilities.LeafyTree.LeafyTree{tc rfw}
                                a1{tv a1qQ} [sk]
                              -> main:Utilities.LeafyTree.LeafyTree{tc rfw} b1{tv a1qR} [sk])
                             -> main:Utilities.ChoiceMonad.ChoiceT{tc rJw}
                                  m{tv aQH} [sk] a1{tv a1qQ} [sk]
                             -> main:Utilities.ChoiceMonad.ChoiceT{tc rJw}
                                  m{tv aQH} [sk] b1{tv a1qR} [sk]
        []
        sat_s20F{v} [lid] =
          main:Utilities.ChoiceMonad.inChoiceT{v rLn} [gid]
            @ m{tv aQH} [sk]
            @ a1{tv a1qQ} [sk]
            @ b1{tv a1qR} [sk]
            $dMonad1{v s20D} [lid] } in
      base:GHC.Base..{v r4k} [gid]
        @ (main:Utilities.LeafyTree.LeafyTree{tc rfw} a1{tv a1qQ} [sk]
           -> main:Utilities.LeafyTree.LeafyTree{tc rfw} b1{tv a1qR} [sk])
        @ (main:Utilities.ChoiceMonad.ChoiceT{tc rJw}
             m{tv aQH} [sk] a1{tv a1qQ} [sk]
           -> main:Utilities.ChoiceMonad.ChoiceT{tc rJw}
                m{tv aQH} [sk] b1{tv a1qR} [sk])
        @ (a1{tv a1qQ} [sk] -> b1{tv a1qR} [sk])
        sat_s20F{v} [lid]
        sat_s20H{v} [lid]
      }

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

but if i do "ghc --make Utilities/ChoiceMonad.hs" that works and I can then load it with ghci-haskline, at least until I modify it and need to compile again.