When installing ghc-4.08.2 (onWinNT) as described in the installation instructions under c:, I couldn't get ghc to run. It invoked the C-preprozessor and stoped after cleaning.

I'm puzzled by this. Could you please send some sample output? Preferably running ghc -v.

When I unmount c:, it works fine. (If I install cygwin and dont mount c: to / it works fine too.) But now //c/ is the normal win-root. That's not a problem for me, but how about ghc?

Well, if it works, I suppose it's not a problem...

Does it depend in any way on c: mounted to /?

I'm not sure. I think it used to (because of using /tmp as the temporary directory). Now it's mostly for convenience.

If not why do you want this mount (in the installation instructions section 2.2.2.1)?

I think it used to be necessary, and I kept it in the instructions partly because I find it useful to be able to refer to the drive with Unix-style paths, with the root directory being /, and partly because it worked, and the less I change the instructions, the less likely I am to break something. -- http://sc3d.org/rrt/ | wit, n. educated insolence (Aristotle)