tree: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched/core head: b2d5b9cec60fecc72a13191c2c6c05acf60975a5 commit: 57a5c2dafca8e3ce4f70e975a9c7727b66b5071f [17/47] sched/rt: Support schedstats for RT sched class config: hexagon-buildonly-randconfig-r002-20211012 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project c3dcf39554dbea780d6cb7e12239451ba47a2668) 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://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git/commit/?id=57... git remote add tip https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git git fetch --no-tags tip sched/core git checkout 57a5c2dafca8e3ce4f70e975a9c7727b66b5071f # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=hexagon 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 >>): kernel/sched/rt.c:669:6: error: no previous prototype for function 'sched_rt_bandwidth_account' [-Werror,-Wmissing-prototypes] bool sched_rt_bandwidth_account(struct rt_rq *rt_rq) ^ kernel/sched/rt.c:669:1: note: declare 'static' if the function is not intended to be used outside of this translation unit bool sched_rt_bandwidth_account(struct rt_rq *rt_rq) ^ static struct task_struct *p = NULL; ^ kernel/sched/rt.c:1311:22: error: variable 'p' set but not used [-Werror,-Wunused-but-set-variable] struct task_struct *p = NULL; ^ kernel/sched/rt.c:1341:22: error: variable 'p' set but not used [-Werror,-Wunused-but-set-variable] struct task_struct *p = NULL; ^ 4 errors generated. vim +/p +1292 kernel/sched/rt.c 1287 1288 static inline void 1289 update_stats_wait_start_rt(struct rt_rq *rt_rq, struct sched_rt_entity *rt_se) 1290 { 1291 struct sched_statistics *stats; 1293 1294 if (!schedstat_enabled()) 1295 return; 1296 1297 if (rt_entity_is_task(rt_se)) 1298 p = rt_task_of(rt_se); 1299 1300 stats = __schedstats_from_rt_se(rt_se); 1301 if (!stats) 1302 return; 1303 1304 __update_stats_wait_start(rq_of_rt_rq(rt_rq), p, stats); 1305 } 1306 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org