Hi Michael, First bad commit (maybe != root cause): tree: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-5.4.y head: f52a40401ee9825556cc803c110c67bfec5f6b94 commit: acac3f7d7d2283a1b8bc1e1c286dcd6c96e573e4 [3700/4278] powerpc: Drop -me200 addition to build flags config: powerpc64-randconfig-r035-20210813 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 62df4df41c939205b2dc0a2a3bfb75b8c1ed74fa) 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 powerpc64 cross compiling tool for clang build # apt-get install binutils-powerpc-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git/commit/?id=acac3f7d7d2283a1b8bc1e1c286dcd6c96e573e4 git remote add linux-stable-rc https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git git fetch --no-tags linux-stable-rc linux-5.4.y git checkout acac3f7d7d2283a1b8bc1e1c286dcd6c96e573e4 # save the attached .config to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross O=build_dir ARCH=powerpc SHELL=/bin/bash M=arch/powerpc If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All errors (new ones prefixed by >>): >> arch/powerpc/math-emu/math_efp.c:927:13: error: a parameter list without types is only allowed in a function definition module_init(spe_mathemu_init); ^ 1 error generated. Kconfig warnings: (for reference only) WARNING: unmet direct dependencies detected for FSL_EMB_PERFMON Depends on E500 || PPC_83xx Selected by - PPC_FSL_BOOK3E vim +927 arch/powerpc/math-emu/math_efp.c ac6f120369ffe6 Liu Yu 2011-01-25 926 ac6f120369ffe6 Liu Yu 2011-01-25 @927 module_init(spe_mathemu_init); :::::: The code at line 927 was first introduced by commit :::::: ac6f120369ffe66058518fabf90cdd53b2503a82 powerpc/85xx: Workaroudn e500 CPU erratum A005 :::::: TO: Liu Yu :::::: CC: Kumar Gala --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org