tree: https://github.com/microchip-ung/linux-upstream.git v5.10-webstax head: 0c603c93d534e71ceee9485bfe1b0b75561efb0e commit: e4904df0bc6023a8a456bb9ca9b6aa7af74c9bc6 [66/88] spi: vcoreiii: Add MSCC vcoreiii bitbang driver config: mips-randconfig-r025-20201214 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project d38205144febf4dc42c9270c6aa3d978f1ef65e1) 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 mips cross compiling tool for clang build # apt-get install binutils-mips-linux-gnu # https://github.com/microchip-ung/linux-upstream/commit/e4904df0bc6023a8a4... git remote add microchip-ung-linux-upstream https://github.com/microchip-ung/linux-upstream.git git fetch --no-tags microchip-ung-linux-upstream v5.10-webstax git checkout e4904df0bc6023a8a456bb9ca9b6aa7af74c9bc6 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=mips 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 >>): int vcoreiii_bb_transfer_one_message(struct spi_master *master, ^ drivers/spi/spi-vcoreiii.c:240:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int vcoreiii_bb_transfer_one_message(struct spi_master *master, ^ static 1 warning generated. vim +/vcoreiii_bb_transfer_one_message +240 drivers/spi/spi-vcoreiii.c 239 241 struct spi_message *msg) 242 { 243 struct spi_vcoreiii *p = spi_master_get_devdata(master); 244 struct spi_device *spi = msg->spi; 245 unsigned int total_len = 0; 246 struct spi_transfer *xfer; 247 248 vcoreiii_bb_cs_activate(p, spi); 249 250 list_for_each_entry(xfer, &msg->transfers, transfer_list) { 251 bool last_xfer = list_is_last(&xfer->transfer_list, 252 &msg->transfers); 253 vcoreiii_bb_do_transfer(p, msg, xfer, last_xfer); 254 total_len += xfer->len; 255 } 256 257 vcoreiii_bb_cs_deactivate(p, spi); 258 259 msg->status = 0; 260 msg->actual_length = total_len; 261 spi_finalize_current_message(master); 262 return msg->status; 263 } 264 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org