tree: https://github.com/intel/linux-intel-lts.git 5.10/yocto head: 1941d4b82f36cc6ecc513f3e496ad62726d00514 commit: c9103da26a3efbbd443b37671f2e19a5e1ac9c14 [18517/20368] OSE TGPIO driver config: i386-allyesconfig (https://download.01.org/0day-ci/archive/20220117/202201170039.cqMfQeA6-lk...) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 650fc40b6d8d9a5869b4fca525d5f237b0ee2803) 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://github.com/intel/linux-intel-lts/commit/c9103da26a3efbbd443b37671... git remote add intel-lts https://github.com/intel/linux-intel-lts.git git fetch --no-tags intel-lts 5.10/yocto git checkout c9103da26a3efbbd443b37671f2e19a5e1ac9c14 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/gpio/ drivers/gpu/drm/i915/ drivers/ptp/ 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 >>): if (scaled_ppm < 0) { ^~~~~~~~~~~~~~ drivers/ptp/ptp-intel-tgpio.c:228:9: note: uninitialized use occurs here reg |= isgn << 31; ^~~~ drivers/ptp/ptp-intel-tgpio.c:215:2: note: remove the 'if' if its condition is always true if (scaled_ppm < 0) { ^~~~~~~~~~~~~~~~~~~~ drivers/ptp/ptp-intel-tgpio.c:212:13: note: initialize the variable 'isgn' to silence this warning bool isgn; ^ = 0 1 warning generated. vim +215 drivers/ptp/ptp-intel-tgpio.c 206 207 static int intel_tgpio_adjfine(struct ptp_clock_info *info, long scaled_ppm) 208 { 209 struct intel_tgpio *tgpio = to_intel_tgpio(info); 210 unsigned long flags; 211 u32 reg; 212 bool isgn; 213 214 spin_lock_irqsave(&tgpio->lock, flags); 216 isgn = true; 217 scaled_ppm = -scaled_ppm; 218 } 219 220 /* 221 * HW uses a 200MHz clock, meaning it has a 5ns period. Just 222 * multiply scaled_ppm by 5 to get our increment. 223 */ 224 reg = 5 * scaled_ppm; 225 226 /* bit 31 is sign bit */ 227 reg &= ~BIT(31); 228 reg |= isgn << 31; 229 230 intel_tgpio_writel(tgpio->base, TIMINCA_GLOBAL, reg); 231 spin_unlock_irqrestore(&tgpio->lock, flags); 232 233 return 0; 234 } 235 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org