Linux -next build failed on arm64 and arm. In file included from net/ipv6/af_inet6.c:41:0: include/linux/netfilter_ipv6.h: In function 'nf_ipv6_cookie_init_sequence': include/linux/netfilter_ipv6.h:174:9: error: implicit declaration of function '__cookie_v6_init_sequence'; did you mean 'cookie_init_sequence'? [-Werror=implicit-function-declaration] return __cookie_v6_init_sequence(iph, th, mssp); ^~~~~~~~~~~~~~~~~~~~~~~~~ cookie_init_sequence include/linux/netfilter_ipv6.h: In function 'nf_cookie_v6_check': include/linux/netfilter_ipv6.h:189:9: error: implicit declaration of function '__cookie_v6_check'; did you mean '__cookie_v4_check'? [-Werror=implicit-function-declaration] return __cookie_v6_check(iph, th, cookie); ^~~~~~~~~~~~~~~~~ __cookie_v4_check CC net/core/net-traces.o CC drivers/char/tpm/eventlog/acpi.o CC fs/proc/page.o cc1: some warnings being treated as errors scripts/Makefile.build:278: recipe for target 'net/ipv6/af_inet6.o' failed make[3]: *** [net/ipv6/af_inet6.o] Error 1 scripts/Makefile.build:489: recipe for target 'net/ipv6' failed make[2]: *** [net/ipv6] Error 2 Best regards Naresh Kamboju