utputFile, setDynOutputFile, setOutputHi, setDumpPrefixForce
   :: Maybe String -> DynFlags -> DynFlags

setObjectDir  f d = d{ objectDir  = Just f}
set
setOutputFile, setDynOutputFile, setOutputHi, setDumpPrefixForce
   :: Maybe String -> DynFlags -> DynFlags
setObjectDir  f d = d{ objectDir  = Just f}
setObjectDir  f d = d{ objectDir  = Just f}