small typo in src/backend/access/transam/xlog.c

BootStrapXLOG(void)

      * to seed it other than the system clock value...)  The upper half of the
         * uint64 value is just the tv_sec part, while the lower half is the XOR
         * of tv_sec and tv_usec.  This is to ensure that we don't lose uniqueness
         * unnecessarily if "uint64" is really only 32 bits wide.  A person
         * knowing this encoding can determine the initialization time of the
         * installation, which could perhaps be useful sometimes.
         */
        gettimeofday(&tv, NULL);
        sysidentifier = ((uint64) tv.tv_sec) << 32;
        sysidentifier |= (uint32) (tv.tv_sec | tv.tv_usec);

should be
        sysidentifier |= (uint32) (tv.tv_sec ^ tv.tv_usec);