-- raiseIO# needs to be a primop, because exceptions in the IO monad
-- must be *precise* - we don't want the strictness analyser turning
-- one kind of bottom into another, as it is allowed to do in pure code.
-- raiseIO# needs to be a primop, because exceptions in the IO monad
-- must be *precise* - we don't want the strictness analyser turning
-- one kind of bottom into another, as it is allowed to do in pure code.