tree: https://git.kernel.org/pub/scm/linux/kernel/git/broonie/misc.git arm64-vdso head: 6b510319fdb2cc4136a47319f6c5e88195b4bcf0 commit: fdf2f42836c8f11889209ddd41450f6d7d0944e3 [4/5] arm64: vdso: Add getcpu() implementation config: arm64-randconfig-r005-20200820 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project b587ca93be114d07ec3bf654add97d7872325281) 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 git checkout fdf2f42836c8f11889209ddd41450f6d7d0944e3 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 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 >>): int __kernel_getcpu(unsigned int *cpu, unsigned int *node, ^ arch/arm64/kernel/vdso/vgetcpu.c:33:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int __kernel_getcpu(unsigned int *cpu, unsigned int *node, ^ static arch/arm64/kernel/vdso/vgettimeofday.c:9:5: warning: no previous prototype for function '__kernel_clock_gettime' [-Wmissing-prototypes] int __kernel_clock_gettime(clockid_t clock, ^ arch/arm64/kernel/vdso/vgettimeofday.c:9:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int __kernel_clock_gettime(clockid_t clock, ^ static arch/arm64/kernel/vdso/vgettimeofday.c:15:5: warning: no previous prototype for function '__kernel_gettimeofday' [-Wmissing-prototypes] int __kernel_gettimeofday(struct __kernel_old_timeval *tv, ^ arch/arm64/kernel/vdso/vgettimeofday.c:15:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int __kernel_gettimeofday(struct __kernel_old_timeval *tv, ^ static arch/arm64/kernel/vdso/vgettimeofday.c:21:5: warning: no previous prototype for function '__kernel_clock_getres' [-Wmissing-prototypes] int __kernel_clock_getres(clockid_t clock_id, ^ arch/arm64/kernel/vdso/vgettimeofday.c:21:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int __kernel_clock_getres(clockid_t clock_id, ^ static 1 warning generated. 3 warnings generated. arch/arm64/kernel/vdso/vdso.so.dbg: dynamic relocations are not supported make[2]: *** [arch/arm64/kernel/vdso/Makefile:65: arch/arm64/kernel/vdso/vdso.so.dbg] Error 1 make[2]: Target 'include/generated/vdso-offsets.h' not remade because of errors. make[1]: *** [arch/arm64/Makefile:182: vdso_prepare] Error 2 make[1]: Target 'prepare' not remade because of errors. make: *** [Makefile:185: __sub-make] Error 2 make: Target 'prepare' not remade because of errors. # https://git.kernel.org/pub/scm/linux/kernel/git/broonie/misc.git/commit/?... git remote add broonie-misc https://git.kernel.org/pub/scm/linux/kernel/git/broonie/misc.git git fetch --no-tags broonie-misc arm64-vdso git checkout fdf2f42836c8f11889209ddd41450f6d7d0944e3 vim +/__kernel_getcpu +33 arch/arm64/kernel/vdso/vgetcpu.c 32 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org