On Sat, Apr 21, 2018 at 09:30:20AM +0200, Manuel Bouyer wrote: > > > > > >- axe_cmd(sc, AXE_CMD_WRITE_MCAST, 0, 0, (void *)&hashtbl); > > >+ axe_cmd(sc, AXE_CMD_WRITE_MCAST, 0, 0, hashtbl); > > > > > >missing & ? > > > > uint8_t hashtbl[8] = { 0, 0, 0, 0, 0, 0, 0, 0 }; > > So I guess the code was wrong before; not sure how multicast could have > worked. No, the address is only needed as rhs of the cast. If passed directly, the address will be used (due to arrays being passed as pointer to first element in C). Try it: #include <stdio.h> #include <inttypes.h> int main(void) { static uint8_t hashtbl[8] = { 0, 0, 0, 0, 0, 0, 0, 0 }; printf("%p vs %p\n", (void *)&hashtbl, hashtbl); return 0; } Martin