tree: https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git sched/core head: 2dfdb3d20ad50e2ae2cb84cbceb0f0fc75e79e5d commit: 0dc533504723599b41a4cefc6697379cddf55787 [14/19] sched: make schedstats helpers independent of fair sched class config: nds32-buildonly-randconfig-r005-20210910 (attached as .config) compiler: nds32le-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://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git/commit/?... git remote add peterz-queue https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git git fetch --no-tags peterz-queue sched/core git checkout 0dc533504723599b41a4cefc6697379cddf55787 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=nds32 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 >>): kernel/sched/fair.c: In function 'update_stats_wait_start_fair': kernel/sched/fair.c:893:29: warning: variable 'p' set but not used [-Wunused-but-set-variable] 893 | struct task_struct *p = NULL; | ^ kernel/sched/fair.c:892:34: warning: variable 'stats' set but not used [-Wunused-but-set-variable] 892 | struct sched_statistics *stats; | ^~~~~ kernel/sched/fair.c: In function 'update_stats_wait_end_fair': kernel/sched/fair.c:910:29: warning: variable 'p' set but not used [-Wunused-but-set-variable] 910 | struct task_struct *p = NULL; | ^ kernel/sched/fair.c:909:34: warning: variable 'stats' set but not used [-Wunused-but-set-variable] 909 | struct sched_statistics *stats; | ^~~~~ In file included from include/linux/sched.h:12, from kernel/sched/sched.h:5, from kernel/sched/fair.c:23: kernel/sched/fair.c: In function 'update_stats_enqueue_sleeper_fair': 10 | #define tsk $r25 | ^~~~ kernel/sched/fair.c:936:29: note: in expansion of macro 'tsk' 936 | struct task_struct *tsk = NULL; | ^~~ kernel/sched/fair.c:935:34: warning: variable 'stats' set but not used [-Wunused-but-set-variable] 935 | struct sched_statistics *stats; | ^~~~~ vim +10 arch/nds32/include/asm/current.h a15e9ffa877852 Greentime Hu 2017-10-24 6 a15e9ffa877852 Greentime Hu 2017-10-24 7 #ifndef __ASSEMBLY__ a15e9ffa877852 Greentime Hu 2017-10-24 8 register struct task_struct *current asm("$r25"); a15e9ffa877852 Greentime Hu 2017-10-24 9 #endif /* __ASSEMBLY__ */ a15e9ffa877852 Greentime Hu 2017-10-24 @10 #define tsk $r25 a15e9ffa877852 Greentime Hu 2017-10-24 11 :::::: The code at line 10 was first introduced by commit :::::: a15e9ffa877852e529db33cc615c132bad2fc60a nds32: Process management :::::: TO: Greentime Hu <greentime(a)andestech.com&gt; :::::: CC: Greentime Hu <greentime(a)andestech.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org