primExit n
ioError (IOError Nothing OtherError "exitWith" "exit should not return")
--- SUP: Although shutdownHaskellAndExit must be called "safe", because it *can*
--- re-enter Haskell land through finalizers
+-- NOTE: shutdownHaskellAndExit must be called "safe", because it *can*
+-- re-enter Haskell land through finalizers.
foreign import ccall "shutdownHaskellAndExit" primExit :: Int -> IO ()
exitFailure :: IO a