+/** Evaluate to non-zero if \a ADDR is an unspecified (all zeros) address. */
+#define irc_in_addr_unspec(ADDR) (((ADDR)->in6_16[0] == 0) \
+ && ((ADDR)->in6_16[1] == 0) \
+ && ((ADDR)->in6_16[2] == 0) \
+ && ((ADDR)->in6_16[3] == 0) \
+ && ((ADDR)->in6_16[4] == 0) \
+ && ((ADDR)->in6_16[6] == 0) \
+ && ((ADDR)->in6_16[7] == 0) \
+ && ((ADDR)->in6_16[5] == 0 \
+ || (ADDR)->in6_16[5] == 65535))