tree: https://github.com/krzk/linux n/power-max17042-maint head: 6571f83efc55435b05ab8080fd5d22ba46185a08 commit: 52a017530b60bb3f6202dd1ffac5e1098c70c876 [2549/3946] hwmon: (nct6775) Use superio_*() function pointers in sio_data. config: parisc-buildonly-randconfig-r006-20210928 (attached as .config) compiler: hppa-linux-gcc (GCC) 11.2.0 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 # https://github.com/krzk/linux/commit/52a017530b60bb3f6202dd1ffac5e1098c70... git remote add krzk-github https://github.com/krzk/linux git fetch --no-tags krzk-github n/power-max17042-maint git checkout 52a017530b60bb3f6202dd1ffac5e1098c70c876 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=parisc 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/hwmon/nct6775.c: In function 'superio_outb': 150 | int ioreg = sio_data->sioreg; | ^~~~~ drivers/hwmon/nct6775.c: In function 'superio_select': drivers/hwmon/nct6775.c:166:13: error: unused variable 'ioreg' [-Werror=unused-variable] 166 | int ioreg = sio_data->sioreg; | ^~~~~ cc1: all warnings being treated as errors vim +/ioreg +150 drivers/hwmon/nct6775.c 147 148 static void superio_outb(struct nct6775_sio_data *sio_data, int reg, int val) 149 { 151 152 outb(reg, ioreg); 153 outb(val, ioreg + 1); 154 } 155 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org