tree: https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git arm64/stacktrace/arch-stack-walk head: e982ef8a4c9b8bc2f92b7cdafbae70aa31b679d1 commit: 36fa81ac0d771ba0080197745a39dbe94562c615 [9/11] arm64: Make profile_pc() use arch_stack_walk() config: arm64-randconfig-r031-20211124 (https://download.01.org/0day-ci/archive/20211125/202111250118.AIirXhgK-lk...) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 67a1c45def8a75061203461ab0060c75c864df1c) 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://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git/commit/?id... git remote add mark https://git.kernel.org/pub/scm/linux/kernel/git/mark/linux.git git fetch --no-tags mark arm64/stacktrace/arch-stack-walk git checkout 36fa81ac0d771ba0080197745a39dbe94562c615 # save the config file to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=arm64 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 >>): arch_stack_walk(profile_pc_cb, &prof_pc, current, regs); ^ arch/arm64/kernel/time.c:55:13: warning: no previous prototype for function 'time_init' [-Wmissing-prototypes] void __init time_init(void) ^ arch/arm64/kernel/time.c:55:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void __init time_init(void) ^ static 1 warning and 1 error generated. vim +/arch_stack_walk +49 arch/arm64/kernel/time.c 44 45 unsigned long profile_pc(struct pt_regs *regs) 46 { 47 unsigned long prof_pc = 0; 48 50 51 return prof_pc; 52 } 53 EXPORT_SYMBOL(profile_pc); 54 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org