Hi Masahiro, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: d72cd4ad4174cfd2257c426ad51e4f53bcfde9c9 commit: 4c8dd95a723d9cccf8810be54aa62be82885c9d8 kbuild: add some extra warning flags unconditionally date: 1 year, 11 months ago config: sh-hp6xx_defconfig (attached as .config) compiler: sh4-linux-gcc (GCC) 9.3.0 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/torvalds/linux.git/commit/?id=4c8dd95a723d9cccf8810be54aa62be82885c9d8 git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 4c8dd95a723d9cccf8810be54aa62be82885c9d8 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross W=1 ARCH=sh If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All errors (new ones prefixed by >>): >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] cc1: all warnings being treated as errors -- >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] arch/sh/kernel/idle.c:32:6: error: no previous prototype for 'arch_cpu_idle_dead' [-Werror=missing-prototypes] 32 | void arch_cpu_idle_dead(void) | ^~~~~~~~~~~~~~~~~~ arch/sh/kernel/idle.c:37:6: error: no previous prototype for 'arch_cpu_idle' [-Werror=missing-prototypes] 37 | void arch_cpu_idle(void) | ^~~~~~~~~~~~~ arch/sh/kernel/idle.c:42:13: error: no previous prototype for 'select_idle_routine' [-Werror=missing-prototypes] 42 | void __init select_idle_routine(void) | ^~~~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors -- >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] arch/sh/kernel/machvec.c: In function 'early_parse_mv': arch/sh/kernel/machvec.c:43:8: error: variable 'mv_comma' set but not used [-Werror=unused-but-set-variable] 43 | char *mv_comma; | ^~~~~~~~ cc1: all warnings being treated as errors -- >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] arch/sh/kernel/ptrace_32.c: In function 'arch_ptrace': arch/sh/kernel/ptrace_32.c:380:26: error: comparison of unsigned expression < 0 is always false [-Werror=type-limits] 380 | if ((addr & 3) || addr < 0 || | ^ arch/sh/kernel/ptrace_32.c:420:26: error: comparison of unsigned expression < 0 is always false [-Werror=type-limits] 420 | if ((addr & 3) || addr < 0 || | ^ cc1: all warnings being treated as errors -- >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] arch/sh/kernel/return_address.c:49:7: error: no previous prototype for 'return_address' [-Werror=missing-prototypes] 49 | void *return_address(unsigned int depth) | ^~~~~~~~~~~~~~ cc1: all warnings being treated as errors -- >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] arch/sh/kernel/sys_sh.c:58:16: error: no previous prototype for 'sys_cacheflush' [-Werror=missing-prototypes] 58 | asmlinkage int sys_cacheflush(unsigned long addr, unsigned long len, int op) | ^~~~~~~~~~~~~~ cc1: all warnings being treated as errors -- >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] arch/sh/kernel/traps_32.c:731:6: error: no previous prototype for 'per_cpu_trap_init' [-Werror=missing-prototypes] 731 | void per_cpu_trap_init(void) | ^~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors -- >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] arch/sh/kernel/hw_breakpoint.c:135:5: error: no previous prototype for 'arch_bp_generic_fields' [-Werror=missing-prototypes] 135 | int arch_bp_generic_fields(int sh_len, int sh_type, | ^~~~~~~~~~~~~~~~~~~~~~ arch/sh/kernel/hw_breakpoint.c: In function 'arch_bp_generic_fields': arch/sh/kernel/hw_breakpoint.c:159:13: error: this statement may fall through [-Werror=implicit-fallthrough=] 159 | *gen_type = HW_BREAKPOINT_R; | ~~~~~~~~~~^~~~~~~~~~~~~~~~~ arch/sh/kernel/hw_breakpoint.c:160:2: note: here 160 | case SH_BREAKPOINT_WRITE: | ^~~~ cc1: all warnings being treated as errors -- >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] arch/sh/mm/cache-sh3.c:93:13: error: no previous prototype for 'sh3_cache_init' [-Werror=missing-prototypes] 93 | void __init sh3_cache_init(void) | ^~~~~~~~~~~~~~ cc1: all warnings being treated as errors -- >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] arch/sh/mm/fault.c:391:27: error: no previous prototype for 'do_page_fault' [-Werror=missing-prototypes] 391 | asmlinkage void __kprobes do_page_fault(struct pt_regs *regs, | ^~~~~~~~~~~~~ cc1: all warnings being treated as errors -- >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] >> cc1: error: arch/sh/include/mach-hp6xx: No such file or directory [-Werror=missing-include-dirs] arch/sh/mm/pgtable.c:12:6: error: no previous prototype for 'pgd_ctor' [-Werror=missing-prototypes] 12 | void pgd_ctor(void *x) | ^~~~~~~~ arch/sh/mm/pgtable.c:33:8: error: no previous prototype for 'pgd_alloc' [-Werror=missing-prototypes] 33 | pgd_t *pgd_alloc(struct mm_struct *mm) | ^~~~~~~~~ arch/sh/mm/pgtable.c:38:6: error: no previous prototype for 'pgd_free' [-Werror=missing-prototypes] 38 | void pgd_free(struct mm_struct *mm, pgd_t *pgd) | ^~~~~~~~ cc1: all warnings being treated as errors .. --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org