tree: https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git queue-4.14 head: 06183267f775415473f3288b24f8754974708b13 commit: dc49b711dd1e8bf56dc312b6e224ca9f71fb94a5 [85/88] perf/core: Flush PMU internal buffers for per-CPU events config: x86_64-randconfig-a016-20210315 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project a28facba1ccdc957f386b7753f4958307f1bfde8) 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 x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git/c... git remote add sashal-linux-stable https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git git fetch --no-tags sashal-linux-stable queue-4.14 git checkout dc49b711dd1e8bf56dc312b6e224ca9f71fb94a5 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 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 >>): static void perf_pmu_sched_task(struct task_struct *prev, ^ kernel/events/core.c:3071:13: note: previous definition is here static void perf_pmu_sched_task(struct task_struct *prev, ^ __perf_pmu_sched_task(cpuctx, sched_in); ^ kernel/events/core.c:3111:3: note: did you mean 'perf_pmu_sched_task'? kernel/events/core.c:3097:13: note: 'perf_pmu_sched_task' declared here static void perf_pmu_sched_task(struct task_struct *prev, ^ kernel/events/core.c:5009:13: warning: no previous prototype for function 'arch_perf_update_userpage' [-Wmissing-prototypes] void __weak arch_perf_update_userpage( ^ kernel/events/core.c:5009:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void __weak arch_perf_update_userpage( ^ static kernel/events/core.c:11201:6: warning: no previous prototype for function 'perf_swevent_init_cpu' [-Wmissing-prototypes] void perf_swevent_init_cpu(unsigned int cpu) ^ kernel/events/core.c:11201:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void perf_swevent_init_cpu(unsigned int cpu) ^ static 2 warnings and 2 errors generated. vim +/perf_pmu_sched_task +3097 kernel/events/core.c 3096 3098 struct task_struct *next, 3099 bool sched_in) 3100 { 3101 struct perf_cpu_context *cpuctx; 3102 3103 if (prev == next) 3104 return; 3105 3106 list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) { 3107 /* will be handled in perf_event_context_sched_in/out */ 3108 if (cpuctx->task_ctx) 3109 continue; 3110 3112 } 3113 } 3114 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org