tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: f01da525b3de8e59b2656b55d40c60462098651f commit: 6decd1aad15f56b169217789630a0098b496de0e MIPS: add support for buggy MT7621S core detection date: 5 weeks ago config: mips-randconfig-r016-20210521 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project bf9ef3efaa99c02e7bfc4c57207301b8de39a278) 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 mips cross compiling tool for clang build # apt-get install binutils-mips-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit... git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 6decd1aad15f56b169217789630a0098b496de0e # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=mips 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 >>): In file included from arch/mips/mti-malta/malta-amon.c:16: struct cpulaunch { ^ arch/mips/include/asm/mips-cps.h:13:10: note: 'arch/mips/include/asm/mips-boards/launch.h' included multiple times, additional include site here #include <asm/mips-boards/launch.h> ^ arch/mips/mti-malta/malta-amon.c:16:10: note: 'arch/mips/include/asm/mips-boards/launch.h' included multiple times, additional include site here #include <asm/mips-boards/launch.h> ^ arch/mips/include/asm/mips-boards/launch.h:8:8: note: unguarded header; consider using #ifdef guards or #pragma once struct cpulaunch { ^ arch/mips/mti-malta/malta-amon.c:19:5: warning: no previous prototype for function 'amon_cpu_avail' [-Wmissing-prototypes] int amon_cpu_avail(int cpu) ^ arch/mips/mti-malta/malta-amon.c:19:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int amon_cpu_avail(int cpu) ^ static arch/mips/mti-malta/malta-amon.c:41:5: warning: no previous prototype for function 'amon_cpu_start' [-Wmissing-prototypes] int amon_cpu_start(int cpu, ^ arch/mips/mti-malta/malta-amon.c:41:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int amon_cpu_start(int cpu, ^ static 2 warnings and 1 error generated. vim +/cpulaunch +8 arch/mips/include/asm/mips-boards/launch.h 39b8d5254246ac5 include/asm-mips/mips-boards/launch.h Ralf Baechle 2008-04-28 7 39b8d5254246ac5 include/asm-mips/mips-boards/launch.h Ralf Baechle 2008-04-28 @8 struct cpulaunch { 39b8d5254246ac5 include/asm-mips/mips-boards/launch.h Ralf Baechle 2008-04-28 9 unsigned long pc; 39b8d5254246ac5 include/asm-mips/mips-boards/launch.h Ralf Baechle 2008-04-28 10 unsigned long gp; 39b8d5254246ac5 include/asm-mips/mips-boards/launch.h Ralf Baechle 2008-04-28 11 unsigned long sp; 39b8d5254246ac5 include/asm-mips/mips-boards/launch.h Ralf Baechle 2008-04-28 12 unsigned long a0; 39b8d5254246ac5 include/asm-mips/mips-boards/launch.h Ralf Baechle 2008-04-28 13 unsigned long _pad[3]; /* pad to cache line size to avoid thrashing */ 39b8d5254246ac5 include/asm-mips/mips-boards/launch.h Ralf Baechle 2008-04-28 14 unsigned long flags; 39b8d5254246ac5 include/asm-mips/mips-boards/launch.h Ralf Baechle 2008-04-28 15 }; 39b8d5254246ac5 include/asm-mips/mips-boards/launch.h Ralf Baechle 2008-04-28 16 :::::: The code at line 8 was first introduced by commit :::::: 39b8d5254246ac56342b72f812255c8f7a74dca9 [MIPS] Add support for MIPS CMP platform. :::::: TO: Ralf Baechle <ralf(a)linux-mips.org&gt; :::::: CC: Ralf Baechle <ralf(a)linux-mips.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org