Examples of errors detected by the V733 diagnostic

V733. It is possible that macro expansion resulted in incorrect evaluation order.

FreeBSD Kernel

V733 It is possible that macro expansion resulted in incorrect evaluation order. Check expression: chan - 1 * 20. isp.c 2301

#define ICB2400_VPOPT_WRITE_SIZE 20

#define  ICB2400_VPINFO_PORT_OFF(chan) \
  (ICB2400_VPINFO_OFF +                \
   sizeof (isp_icb_2400_vpinfo_t) +    \
  (chan * ICB2400_VPOPT_WRITE_SIZE))          // <=

static void
isp_fibre_init_2400(ispsoftc_t *isp)
{
  ....
  if (ISP_CAP_VP0(isp))
    off += ICB2400_VPINFO_PORT_OFF(chan);
  else
    off += ICB2400_VPINFO_PORT_OFF(chan - 1); // <=
  ....
}

Linux Kernel

V733 It is possible that macro expansion resulted in incorrect evaluation order. Check expression: request->rq_timeout + 5 * 1000. niobuf.c 637

#define CFS_FAIL_TIMEOUT(id, secs) \
cfs_fail_timeout_set(id, 0, secs * 1000, CFS_FAIL_LOC_NOSET)

#define OBD_FAIL_TIMEOUT(id, secs) \
CFS_FAIL_TIMEOUT(id, secs)

int ptl_send_rpc(struct ptlrpc_request *request, int noreply)
{
  ....
  OBD_FAIL_TIMEOUT(OBD_FAIL_PTLRPC_DELAY_SEND,
                   request->rq_timeout + 5);
  ....
}