tree: https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-nomadik.git ux500-href-charging-v5.16-rc1-prim head: 86b93a3192d2eb04134708293a8274948d210db4 commit: 86b93a3192d2eb04134708293a8274948d210db4 [35/35] samsung hack config: riscv-randconfig-r026-20211214 (https://download.01.org/0day-ci/archive/20211215/202112152004.1gns6xiD-lk...) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project b6a2ddb6c8ac29412b1361810972e15221fa021c) 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 riscv cross compiling tool for clang build # apt-get install binutils-riscv64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-nomadik.git/... git remote add linusw-nomadik https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-nomadik.git git fetch --no-tags linusw-nomadik ux500-href-charging-v5.16-rc1-prim git checkout 86b93a3192d2eb04134708293a8274948d210db4 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): drivers/power/supply/samsung-sdi-battery.c:55:5: warning: no previous prototype for function 'samsung_sdi_battery_get_info' [-Wmissing-prototypes] int samsung_sdi_battery_get_info(struct power_supply_battery_info **info, ^ drivers/power/supply/samsung-sdi-battery.c:55:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int samsung_sdi_battery_get_info(struct power_supply_battery_info **info, ^ static } ^ 1 warning and 1 error generated. vim +71 drivers/power/supply/samsung-sdi-battery.c 54 55 int samsung_sdi_battery_get_info(struct power_supply_battery_info **info, 56 struct device_node *np) 57 { 58 struct samsung_sdi_battery *batt; 59 int i; 60 61 for (i = 0; i < ARRAY_SIZE(samsung_sdi_batteries); i++) { 62 batt = &samsung_sdi_batteries[i]; 63 if (of_device_is_compatible(np, batt->compatible)) 64 break; 65 } 66 67 if (i == ARRAY_SIZE(samsung_sdi_batteries)) 68 return -ENODEV; 69 70 *info = &batt->info; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org