[kbuild-all] [linux-rt-devel:linux-5.10.y-rt-rebase 80/248] kernel/printk/printk.c:2581:6: error: implicit declaration of function 'kernel_sync_mode'

tree: https://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-5.10.y-rt-rebase head: 13ce1b83bb2b44f074b4fda849bb8b200adca084 commit: c95870903b0a88c5661755d5ab1f5cba6efa3de9 [80/248] printk: introduce kernel sync mode config: sparc-allnoconfig (attached as .config) compiler: sparc-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/rt/linux-rt-devel.git/com... git remote add linux-rt-devel https://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git git fetch --no-tags linux-rt-devel linux-5.10.y-rt-rebase git checkout c95870903b0a88c5661755d5ab1f5cba6efa3de9 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=sparc If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): In file included from kernel/printk/printk.c:62: kernel/printk/internal.h:56:20: warning: no previous prototype for 'vprintk_func' [-Wmissing-prototypes] 56 | __printf(1, 0) int vprintk_func(const char *fmt, va_list args) { return 0; } | ^~~~~~~~~~~~ kernel/printk/printk.c:179:5: warning: no previous prototype for 'devkmsg_sysctl_set_loglvl' [-Wmissing-prototypes] 179 | int devkmsg_sysctl_set_loglvl(struct ctl_table *table, int write, | ^~~~~~~~~~~~~~~~~~~~~~~~~ kernel/printk/printk.c:2297:33: error: implicit declaration of function 'ATOMI64_INIT'; did you mean 'ATOMIC64_INIT'? [-Werror=implicit-function-declaration] 2297 | static atomic64_t console_seq = ATOMI64_INIT(0); | ^~~~~~~~~~~~ | ATOMIC64_INIT kernel/printk/printk.c:2297:33: error: invalid initializer kernel/printk/printk.c: In function 'can_use_console': 2581 | if (kernel_sync_mode()) | ^~~~~~~~~~~~~~~~ kernel/printk/printk.c: At top level: kernel/printk/printk.c:3693:6: warning: no previous prototype for 'prb_lock' [-Wmissing-prototypes] 3693 | void prb_lock(struct prb_cpulock *cpu_lock, unsigned int *cpu_store) | ^~~~~~~~ kernel/printk/printk.c:3711:6: warning: no previous prototype for 'prb_unlock' [-Wmissing-prototypes] 3711 | void prb_unlock(struct prb_cpulock *cpu_lock, unsigned int cpu_store) | ^~~~~~~~~~ kernel/printk/printk.c:83:13: warning: 'sync_mode' defined but not used [-Wunused-variable] 83 | static bool sync_mode; | ^~~~~~~~~ cc1: some warnings being treated as errors vim +/kernel_sync_mode +2581 kernel/printk/printk.c 2571 2572 /* 2573 * Can we actually use the console at this time on this cpu? 2574 * 2575 * Console drivers may assume that per-cpu resources have been allocated. So 2576 * unless they're explicitly marked as being able to cope (CON_ANYTIME) don't 2577 * call them until this CPU is officially up. 2578 */ 2579 static inline int can_use_console(void) 2580 { 2582 return false; 2583 return cpu_online(raw_smp_processor_id()) || have_callable_console(); 2584 } 2585 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org