tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git x86/fpu-3-kvm head: 567aa15fa5d336b777bd277f52412bd9f8be1585 commit: 22553a4cfe428edf5b399552abc2ffd22918c4a9 [26/65] x86/fpu: Remove internal.h dependency from fpu/signal.h config: x86_64-buildonly-randconfig-r003-20211015 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 6069a6a5049497a32a50a49661c2f4169078bdba) 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 # https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git/commit/?id... git remote add tglx-devel https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git git fetch --no-tags tglx-devel x86/fpu-3-kvm git checkout 22553a4cfe428edf5b399552abc2ffd22918c4a9 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 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 >>): void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask) ^ arch/x86/kernel/ptrace.c:1311:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask) ^ static 1 error generated. vim +/update_regset_xstate_info +1311 arch/x86/kernel/ptrace.c 5b3efd500854d4 Suresh Siddha 2010-02-11 1310 404f6aac9b3ef5 Kees Cook 2016-08-08 @1311 void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask) 5b3efd500854d4 Suresh Siddha 2010-02-11 1312 { 5b3efd500854d4 Suresh Siddha 2010-02-11 1313 #ifdef CONFIG_X86_64 5b3efd500854d4 Suresh Siddha 2010-02-11 1314 x86_64_regsets[REGSET_XSTATE].n = size / sizeof(u64); 5b3efd500854d4 Suresh Siddha 2010-02-11 1315 #endif 5b3efd500854d4 Suresh Siddha 2010-02-11 1316 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION 5b3efd500854d4 Suresh Siddha 2010-02-11 1317 x86_32_regsets[REGSET_XSTATE].n = size / sizeof(u64); 5b3efd500854d4 Suresh Siddha 2010-02-11 1318 #endif 5b3efd500854d4 Suresh Siddha 2010-02-11 1319 xstate_fx_sw_bytes[USER_XSTATE_XCR0_WORD] = xstate_mask; 5b3efd500854d4 Suresh Siddha 2010-02-11 1320 } 5b3efd500854d4 Suresh Siddha 2010-02-11 1321 :::::: The code at line 1311 was first introduced by commit :::::: 404f6aac9b3ef595735feca99979db084ea48315 x86: Apply more __ro_after_init and const :::::: TO: Kees Cook <keescook(a)chromium.org&gt; :::::: CC: Ingo Molnar <mingo(a)kernel.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org