#if defined(__FreeBSD__) && defined(__FreeBSD_version) && __FreeBSD_version >= 1100110
# define MDB_USE_POSIX_MUTEX 1
# define MDB_USE_ROBUST 1
-#elif defined(__APPLE__) && !defined(MDB_USE_ROBUST)
-# define MDB_USE_POSIX_SEM 1
#elif defined(__APPLE__) || defined (BSD) || defined(__FreeBSD_kernel__)
+# if defined(__APPLE__) && !defined(MDB_USE_ROBUST)
+# define MSB_USE_POSIX_SEM 1
+# endif
# if !(defined(MDB_USE_POSIX_MUTEX) || defined(MDB_USE_POSIX_SEM))
# define MDB_USE_SYSV_SEM 1
# endif