can't validate on Mac

Hi devs, In a (almost) clean validate on my MacOS 10.8 machine, I see this: {{{ rts/posix/OSMem.c: In function 'my_mmap': rts/posix/OSMem.c:109:15: error: error: variable 'flags' set but not used [-Werror=unused-but-set-variable] int prot, flags; ^ rts/posix/OSMem.c:109:9: error: error: variable 'prot' set but not used [-Werror=unused-but-set-variable] int prot, flags; ^ cc1: all warnings being treated as errors }}} Help? Thanks, Richard