> #if sizeof(daddr_t) > sizeof(int) (or uint32_t, or whatever the "small"
> daddr_t version actually uses)?

Nope - you can't use sizeof() in a preprocessor expression.
(I did check because gcc could manage to do it, but it would tend
to break the parsing rules.  Traditional C (with a separate cpp)
can't possibly support it.)

	David

-- 
David Laight: david@l8s.co.uk