tree: https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git to-build head: 5fd3eccb73a30251d944935959498ca308848a54 commit: cae2b1064d5a147bffbd0447f9cd264b140b7f72 [37/41] net: split out ndo_siowandev ioctl config: x86_64-randconfig-a003-20210517 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 0a34ff8bcb1df16fe7d643ccbe4567b2162c5024) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/commi... git remote add arnd-playground https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git git fetch --no-tags arnd-playground to-build git checkout cae2b1064d5a147bffbd0447f9cd264b140b7f72 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): int lmc_proto_ioctl(lmc_softc_t *sc, struct if_settings *ifs) ^ drivers/net/wan/lmc/lmc_proto.c:61:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int lmc_proto_ioctl(lmc_softc_t *sc, struct if_settings *ifs) ^ static 1 warning generated. vim +/lmc_proto_ioctl +61 drivers/net/wan/lmc/lmc_proto.c 60 62 { 63 if (sc->if_type == LMC_PPP) 64 return hdlc_ioctl(sc->lmc_device, ifs); 65 return -EOPNOTSUPP; 66 } 67 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org