Compiler warnings lwip / xemacpsif.c

Start in embeddedsw/ThirdParty/sw_services/lwip211/src/contrib/ports/xilinx/netif/xemacpsif.c and compare xemacpsif_output and the MAC filter callbacks with the lwIP callback declarations shown in the warnings. Review the corresponding declarations in lwip/src/include/netif/etharp.h and the netif headers, then rebuild the affected lwIP target. Done means these incompatible-pointer-type warnings no longer occur.

There are a couple of warnings coming from xemacpsif.c

1. Cast from ip_addr_t * to ip4/6_addr_t* missing
2. Callback functions do not match the signatures defined by lwip

../../embeddedsw/ThirdParty/sw_services/lwip211/src/contrib/ports/xilinx/netif/xemacpsif.c: In function 'xemacpsif_output':
../../embeddedsw/ThirdParty/sw_services/lwip211/src/contrib/ports/xilinx/netif/xemacpsif.c:242:40: warning: passing argument 3 of 'etharp_output' from incompatible pointer type [-Wincompatible-pointer-types]
  242 |         return etharp_output(netif, p, ipaddr);
      |                                        ^~~~~~
      |                                        |
      |                                        const ip_addr_t * {aka const struct ip_addr *}
In file included from ../../lwip/src/include/netif/etharp.h:2,
                 from ../../embeddedsw/ThirdParty/sw_services/lwip211/src/contrib/ports/xilinx/netif/xemacpsif.c:45:
../../lwip/src/include/lwip/etharp.h:81:76: note: expected 'const ip4_addr_t *' {aka 'const struct ip4_addr *'} but argument is of type 'const ip_addr_t *' {aka 'const struct ip_addr *'}
   81 | err_t etharp_output(struct netif *netif, struct pbuf *q, const ip4_addr_t *ipaddr);
      |                                                          ~~~~~~~~~~~~~~~~~~^~~~~~
../../embeddedsw/ThirdParty/sw_services/lwip211/src/contrib/ports/xilinx/netif/xemacpsif.c: In function 'low_level_init':
../../embeddedsw/ThirdParty/sw_services/lwip211/src/contrib/ports/xilinx/netif/xemacpsif.c:377:24: warning: assignment to 'netif_mld_mac_filter_fn' {aka 'signed char (*)(struct netif *, const struct ip6_addr *, enum netif_mac_filter_action)'} from incompatible pointer type 'err_t (*)(struct netif *, ip_addr_t *, u8_t)' {aka 'signed char (*)(struct netif *, struct ip_addr *, unsigned char)'} [-Wincompatible-pointer-types]
  377 |  netif->mld_mac_filter = xemacpsif_mld6_mac_filter_update;
      |                        ^
../../embeddedsw/ThirdParty/sw_services/lwip211/src/contrib/ports/xilinx/netif/xemacpsif.c: In function 'xemacpsif_init':
../../embeddedsw/ThirdParty/sw_services/lwip211/src/contrib/ports/xilinx/netif/xemacpsif.c:768:23: warning: assignment to 'netif_output_fn' {aka 'signed char (*)(struct netif *, struct pbuf *, const struct ip4_addr *)'} from incompatible pointer type 'err_t (*)(struct netif *, struct pbuf *, const ip_addr_t *)' {aka 'signed char (*)(struct netif *, struct pbuf *, const struct ip_addr *)'} [-Wincompatible-pointer-types]
  768 |         netif->output = xemacpsif_output;
      |                 

Should become something like:

static err_t xemacpsif_mac_filter_update (struct netif *netif,
							const ip4_addr_t *group,
							enum netif_mac_filter_action action);

static err_t xemacpsif_mld6_mac_filter_update (struct netif *netif,
							const ip6_addr_t *group,
							enum netif_mac_filter_action action);

static err_t xemacpsif_output(struct netif *netif, struct pbuf *p,
		const ip4_addr_t *ipaddr)
{
	/* resolve hardware address, then send (or queue) packet */
	return etharp_output(netif, p, (const ip4_addr_t*) ipaddr);
}

static err_t xemacpsif_mld6_mac_filter_update (struct netif *netif,
							const ip6_addr_t *group,
							enum netif_mac_filter_action action)
{
	u8_t temp_mask;
	unsigned int i;
	u8_t * ip_addr = (u8_t *) group;

	if(!(xemacpsif_ip6_addr_ismulticast((ip6_addr_t*) group ))) {

static void xemacpsif_mac_hash_update (struct netif *netif, u8_t *ip4_addr_t,
		enum netif_mac_filter_action action)