tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: b3c0a155ef77550d48f6eb7c6fdd6075764a5622 commit: 672513bf583157cc088a32e75bd850dd9f81564c [122/4212] ARM: decompressor: disable stack protector config: arm-buildonly-randconfig-r004-20220207 (https://download.01.org/0day-ci/archive/20220208/202202080808.lrsdrLFj-lk...) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 0d8850ae2cae85d49bea6ae0799fa41c7202c05c) 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 arm cross compiling tool for clang build # apt-get install binutils-arm-linux-gnueabi # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commi... git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch --no-tags linux-next master git checkout 672513bf583157cc088a32e75bd850dd9f81564c # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash 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 >>): arch/arm/boot/compressed/atags_to_fdt.c:129:5: warning: no previous prototype for function 'atags_to_fdt' [-Wmissing-prototypes] int atags_to_fdt(void *atag_list, void *fdt, int total_space) ^ arch/arm/boot/compressed/atags_to_fdt.c:129:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int atags_to_fdt(void *atag_list, void *fdt, int total_space) ^ static int atags_to_fdt(void *atag_list, void *fdt, int total_space) ^ 2 warnings generated. vim +/atags_to_fdt +129 arch/arm/boot/compressed/atags_to_fdt.c 31d0b9f9982f8e Ben Dooks 2018-10-12 120 b90b9a38251e9c Nicolas Pitre 2011-09-13 121 /* b90b9a38251e9c Nicolas Pitre 2011-09-13 122 * Convert and fold provided ATAGs into the provided FDT. b90b9a38251e9c Nicolas Pitre 2011-09-13 123 * 4716e2e34a22a8 Geert Uytterhoeven 2021-05-19 124 * Return values: b90b9a38251e9c Nicolas Pitre 2011-09-13 125 * = 0 -> pretend success b90b9a38251e9c Nicolas Pitre 2011-09-13 126 * = 1 -> bad ATAG (may retry with another possible ATAG pointer) b90b9a38251e9c Nicolas Pitre 2011-09-13 127 * < 0 -> error from libfdt b90b9a38251e9c Nicolas Pitre 2011-09-13 128 */ b90b9a38251e9c Nicolas Pitre 2011-09-13 @129 int atags_to_fdt(void *atag_list, void *fdt, int total_space) :::::: The code at line 129 was first introduced by commit :::::: b90b9a38251e9c89c34179eccde57411ceb5f1aa ARM: zImage: allow supplementing appended DTB with traditional ATAG data :::::: TO: Nicolas Pitre <nicolas.pitre(a)linaro.org&gt; :::::: CC: Nicolas Pitre <nico(a)fluxnic.net&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org