As explained in this thread:

http://www.haskell.org/pipermail/haskell-cafe/2008-February/039549.html

getSymbolicLinkStatus (and possibly other functions) return completely
bogus results. This is because hsc2hs returns the offsets for stat64,
but the library is built such that it calls the 32 bit lstat call.

I copied the AC_SYS_LARGEFILE from ghc's configure.ac. So, I believe
the library should now properly autodetect whether your system has
large file support and do the right thing more often. I suspect that
this would still be buggy if ghc was built without large file support,
but the library was built with it enabled. However, as long as
AC_SYS_LARGEFILE returns the same results for 'ghc' and 'unix', things
should be ok ?