Hi,
On the new Darwin 10.8 (aka mountain lion), I had to add
#ifdef __APPLE__
#if (__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 1080)
#define _XOPEN_SOURCE
#endif
#endif
to the very beginning of contrib/uuid-ossp/uuid-ossp.c to get the build
working with --with-ossp-uuid.
I suggested something similar to the macports guys, but I guess it would
be wise to get this upstream to the postgresql source?
Cheers,
Palle