Hi Nick, First bad commit (maybe != root cause): tree: https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git for-next head: f12b034afeb3a977bbb1c6584dedc0f3dc666f14 commit: f12b034afeb3a977bbb1c6584dedc0f3dc666f14 [9/9] scripts/Makefile.clang: default to LLVM_IAS=1 config: arm-randconfig-r003-20210809 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 614c7d03877fd99c2de47429b15be3f00306a3bd) 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/masahiroy/linux-kbuild.git/commit/?id=f12b034afeb3a977bbb1c6584dedc0f3dc666f14 git remote add masahiroy https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git git fetch --no-tags masahiroy for-next git checkout f12b034afeb3a977bbb1c6584dedc0f3dc666f14 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All warnings (new ones prefixed by >>): >> arch/arm/mach-integrator/integrator_ap.c:150:13: warning: no previous prototype for function 'ap_init_early' [-Wmissing-prototypes] void __init ap_init_early(void) ^ arch/arm/mach-integrator/integrator_ap.c:150:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void __init ap_init_early(void) ^ static 1 warning generated. -- >> drivers/hsi/controllers/omap_ssi_core.c:147:6: warning: no previous prototype for function 'ssi_waketest' [-Wmissing-prototypes] void ssi_waketest(struct hsi_client *cl, unsigned int enable) ^ drivers/hsi/controllers/omap_ssi_core.c:147:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void ssi_waketest(struct hsi_client *cl, unsigned int enable) ^ static 1 warning generated. vim +/ap_init_early +150 arch/arm/mach-integrator/integrator_ap.c 379df2793efdca Linus Walleij 2012-11-17 149 a613163dff04cb Linus Walleij 2012-06-11 @150 void __init ap_init_early(void) a613163dff04cb Linus Walleij 2012-06-11 151 { a613163dff04cb Linus Walleij 2012-06-11 152 } a613163dff04cb Linus Walleij 2012-06-11 153 :::::: The code at line 150 was first introduced by commit :::::: a613163dff04cbfcb7d66b06ef4a5f65498ee59b ARM: integrator: convert to common clock :::::: TO: Linus Walleij :::::: CC: Mike Turquette --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org