tree: https://git.kernel.org/pub/scm/linux/kernel/git/joro/linux.git sev-es-client-v5.8-rc4 head: 7ee5e0ddab7fa6efbf0937f175a5688a375d55b8 commit: 54f06047709499a1f9fe35cb59e4304089b72e22 [35/75] x86/head/64: Load IDT earlier config: x86_64-randconfig-r002-20200710 (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 02946de3802d3bc65bc9f2eb9b8d4969b5a7add8) 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 git checkout 54f06047709499a1f9fe35cb59e4304089b72e22 # 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 warnings (new ones prefixed by >>): void __head early_idt_setup_early_handler(struct desc_ptr *descr, unsigned long physaddr) ^ arch/x86/kernel/head64.c:512:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void __head early_idt_setup_early_handler(struct desc_ptr *descr, unsigned long physaddr) ^ static 1 warning generated. vim +/early_idt_setup_early_handler +512 arch/x86/kernel/head64.c 511 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org