Hi Matti, [FYI, it's a private test report for your RFC patch.] [auto build test WARNING on 09162bc32c880a791c6c0668ce0745cf7958f576] url: https://github.com/0day-ci/linux/commits/Matti-Vaittinen/power-supply-Add... base: 09162bc32c880a791c6c0668ce0745cf7958f576 config: arm64-randconfig-r005-20201210 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 1968804ac726e7674d5de22bc2204b45857da344) 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 arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu # https://github.com/0day-ci/linux/commit/d7d68650b1fb6da80b5ba5953454bae6b... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Matti-Vaittinen/power-supply-Add-some-fuel-gauge-logic/20201204-205731 git checkout d7d68650b1fb6da80b5ba5953454bae6bbe420da # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 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 >>): if (sw->ops.set_cycle) ^~~~~~~~~~~~~~~~~~~~~~ include/linux/compiler.h:56:28: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/compiler.h:58:30: note: expanded from macro '__trace_if_var' #define __trace_if_var(cond) (__builtin_constant_p(cond) ? (cond) : __trace_if_value(cond)) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/power/supply/power_supply_swgauge.c:111:9: note: uninitialized use occurs here return ret; ^~~ drivers/power/supply/power_supply_swgauge.c:105:2: note: remove the 'if' if its condition is always true if (sw->ops.set_cycle) ^~~~~~~~~~~~~~~~~~~~~~ include/linux/compiler.h:56:23: note: expanded from macro 'if' #define if(cond, ...) if ( __trace_if_var( !!(cond , ## __VA_ARGS__) ) ) ^ drivers/power/supply/power_supply_swgauge.c:100:9: note: initialize the variable 'ret' to silence this warning int ret, old_cycle = sw->cycle; ^ = 0 drivers/power/supply/power_supply_swgauge.c:818:6: warning: no previous prototype for function 'stop_gauge_thread' [-Wmissing-prototypes] void stop_gauge_thread(struct task_struct *k) ^ drivers/power/supply/power_supply_swgauge.c:818:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void stop_gauge_thread(struct task_struct *k) ^ static 2 warnings generated. vim +105 drivers/power/supply/power_supply_swgauge.c 97 98 static int swgauge_set_cycle(struct sw_gauge *sw, int new_cycle) 99 { 100 int ret, old_cycle = sw->cycle; 101 102 if (!sw->desc->allow_set_cycle && !sw->ops.set_cycle) 103 return -EINVAL; 104 106 ret = sw->ops.set_cycle(sw, old_cycle, &new_cycle); 107 108 if (!ret) 109 sw->cycle = new_cycle; 110 111 return ret; 112 } 113 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org