Hi Jeff, [FYI, it's a private test report for your RFC patch.] [auto build test WARNING on ipvs/master] [also build test WARNING on linus/master v5.9 next-20201016] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Jeff-Dike/Exempt-multicast-addre... base: https://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs.git master config: nios2-randconfig-s031-20201016 (attached as .config) compiler: nios2-linux-gcc (GCC) 9.3.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # apt-get install sparse # sparse version: v0.6.3-rc1-2-g368fd9ce-dirty # https://github.com/0day-ci/linux/commit/3afd4b26a439959c7e9250ea6ede30645... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Jeff-Dike/Exempt-multicast-address-from-five-second-neighbor-lifetime/20201016-234627 git checkout 3afd4b26a439959c7e9250ea6ede30645bb4f2ff # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=nios2 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; "sparse warnings: (new ones prefixed by >>)" vim +936 net/ipv4/arp.c 933 934 static int arp_is_multicast(const void *pkey) 935 { 937 } 938 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org