Hi Tim, FYI, the error/warning still remains. tree: https://gitee.com/openeuler/kernel.git OLK-5.10 head: c9c7afae6802fd2282529d80c0f808360f7b654a commit: f4128ae8e6ff03b4c805707fe75d0345797f7f53 [23034/30000] sched: Add cluster scheduler level for x86 config: x86_64-buildonly-randconfig-002-20241010 (https://download.01.org/0day-ci/archive/20241010/202410100921.MexAROBI-lkp@i...) compiler: clang version 18.1.8 (https://github.com/llvm/llvm-project 3b5b5c1ec4a3095ab096dd780e84d7ab81f3d7ff) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241010/202410100921.MexAROBI-lkp@i...) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202410100921.MexAROBI-lkp@intel.com/ All errors (new ones prefixed by >>): In file included from kernel/sched/topology.c:5: kernel/sched/sched.h:1838:15: warning: cast from 'void (*)(struct rq *)' to 'void (*)(struct callback_head *)' converts to incompatible function type [-Wcast-function-type-strict] 1838 | head->func = (void (*)(struct callback_head *))func; | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/sched/topology.c:718:6: warning: variable 'numa_distance' set but not used [-Wunused-but-set-variable] 718 | int numa_distance = 0; | ^

...

kernel/sched/topology.c:1749:2: error: implicit declaration of function 'register_sysctl_init' [-Werror,-Wimplicit-function-declaration] 1749 | register_sysctl_init("kernel", sched_cluster_sysctls); | ^ 2 warnings and 1 error generated.

vim +/register_sysctl_init +1749 kernel/sched/topology.c 8ce3e706b314091 Tim Chen 2021-12-03 1746 8ce3e706b314091 Tim Chen 2021-12-03 1747 static int __init sched_cluster_sysctl_init(void) 8ce3e706b314091 Tim Chen 2021-12-03 1748 { 8ce3e706b314091 Tim Chen 2021-12-03 @1749 register_sysctl_init("kernel", sched_cluster_sysctls); 8ce3e706b314091 Tim Chen 2021-12-03 1750 return 0; 8ce3e706b314091 Tim Chen 2021-12-03 1751 } 8ce3e706b314091 Tim Chen 2021-12-03 1752 late_initcall(sched_cluster_sysctl_init); 9e68cc2bf535a2f Tim Chen 2021-12-03 1753 :::::: The code at line 1749 was first introduced by commit :::::: 8ce3e706b31409147f035c037055caa68e450ce5 scheduler: Add runtime knob sysctl_sched_cluster :::::: TO: Tim Chen <tim.c.chen@linux.intel.com> :::::: CC: Jie Liu <liujie375@h-partners.com> -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki