Use of cpp

[Adrian Hey]

Hello,

I've just modified some Haskell code from the AVL library to explicitly
use ghc unboxed Ints in some routines.

Unfortunately, I've broken portability by doing this and was considering some
cpp magic to restore portability. But IIRC, the use of cpp is discouraged for
Haskell library infrastructure.

Is that so? If so, what should I use instead?
Is cpphs the way to go?

Thanks
--
Adrian Hey