Hi Yizhen, FYI, the error/warning still remains. tree: https://gitee.com/openeuler/kernel.git OLK-5.10 head: 929a9df37c1b7dec73fd417d79a116d02a8f9380 commit: 95c713224477ac3433652331dd715e9bbcbc793a [2417/2417] ub: init ubcore module config: x86_64-buildonly-randconfig-002-20241112 (https://download.01.org/0day-ci/archive/20241203/202412030157.Es0GoXeE-lkp@i...) compiler: gcc-11 (Debian 11.3.0-12) 11.3.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241203/202412030157.Es0GoXeE-lkp@i...) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202412030157.Es0GoXeE-lkp@intel.com/ All warnings (new ones prefixed by >>):

...

drivers/ub/urma/ubcore/ubcore_main.c:61:5: warning: no previous prototype for 'ubcore_open' [-Wmissing-prototypes] 61 | int ubcore_open(struct inode *i_node, struct file *filp) | ^~~~~~~~~~~

vim +/ubcore_open +61 drivers/ub/urma/ubcore/ubcore_main.c 60

61 int ubcore_open(struct inode *i_node, struct file *filp) 62 { 63 return 0; 64 } 65

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