Hi Lorenz, kernel test robot noticed the following build warnings: [auto build test WARNING on 25085b4e9251c77758964a8e8651338972353642] url: https://github.com/intel-lab-lkp/linux/commits/Lorenz-Bauer/net-export-inet_lookup_reuseport-and-inet6_lookup_reuseport/20230613-181619 base: 25085b4e9251c77758964a8e8651338972353642 patch link: https://lore.kernel.org/r/20230613-so-reuseport-v2-3-b7c69a342613%40isovalent.com patch subject: [PATCH bpf-next v2 3/6] net: remove duplicate reuseport_lookup functions config: i386-defconfig (https://download.01.org/0day-ci/archive/20230614/202306140138.DnwjedJ1-lkp@xxxxxxxxx/config) compiler: gcc-12 (Debian 12.2.0-14) 12.2.0 reproduce (this is a W=1 build): git checkout 25085b4e9251c77758964a8e8651338972353642 b4 shazam https://lore.kernel.org/r/20230613-so-reuseport-v2-3-b7c69a342613@xxxxxxxxxxxxx # save the config file mkdir build_dir && cp config build_dir/.config make W=1 O=build_dir ARCH=i386 olddefconfig make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash net/ipv4/ net/ipv6/ If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202306140138.DnwjedJ1-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): >> net/ipv4/udp.c:409:5: warning: no previous prototype for 'udp_ehashfn' [-Wmissing-prototypes] 409 | u32 udp_ehashfn(const struct net *net, const __be32 laddr, const __u16 lport, | ^~~~~~~~~~~ -- >> net/ipv6/udp.c:74:5: warning: no previous prototype for 'udp6_ehashfn' [-Wmissing-prototypes] 74 | u32 udp6_ehashfn(const struct net *net, | ^~~~~~~~~~~~ vim +/udp_ehashfn +409 net/ipv4/udp.c 407 408 INDIRECT_CALLABLE_SCOPE > 409 u32 udp_ehashfn(const struct net *net, const __be32 laddr, const __u16 lport, 410 const __be32 faddr, const __be16 fport) 411 { 412 static u32 udp_ehash_secret __read_mostly; 413 414 net_get_random_once(&udp_ehash_secret, sizeof(udp_ehash_secret)); 415 416 return __inet_ehashfn(laddr, lport, faddr, fport, 417 udp_ehash_secret + net_hash_mix(net)); 418 } 419 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki