tree: https://git.kernel.org/pub/scm/linux/kernel/git/ast/bpf.git relo_core head: 5e4dbbcc690eda4eadfb2e46900a55051c5a7f6b commit: 5b743311a94271672b8c3770aef0a6be426f8a0c [4/9] bpf: Prepare relo_core.c for kernel duty. config: arc-randconfig-r032-20210913 (attached as .config) compiler: arceb-elf-gcc (GCC) 11.2.0 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/ast/bpf.git/commit/?id=5b... git remote add ast https://git.kernel.org/pub/scm/linux/kernel/git/ast/bpf.git git fetch --no-tags ast relo_core git checkout 5b743311a94271672b8c3770aef0a6be426f8a0c # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=arc 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 >>): 75 | void libbpf_print(enum libbpf_print_level level, | ^~~~~~~~~~~~ tools/lib/bpf/relo_core.c: In function 'bpf_core_apply_relo_insn': 1388 | } | ^ vim +/libbpf_print +75 tools/lib/bpf/relo_core.c 68 69 enum libbpf_print_level { 70 LIBBPF_WARN, 71 LIBBPF_INFO, 72 LIBBPF_DEBUG, 73 }; 74 __attribute__((format(printf, 2, 3))) 76 const char *format, ...) 77 { 78 } 79 #define __pr(level, fmt, ...) \ 80 do { \ 81 libbpf_print(level, "libbpf: " fmt, ##__VA_ARGS__); \ 82 } while (0) 83 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org