tree: https://github.com/norov/linux find_bit_smallconst_v4 head: 747508d50b9b17dcf850b2a9c07156bf52e147df commit: 1c7083bf4aab3b8d9dedc5155a5a82741cc161bc [11/13] lib: add fast path for find_first_*_bit() and find_last_bit() config: sh-randconfig-m031-20210312 (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://github.com/norov/linux/commit/1c7083bf4aab3b8d9dedc5155a5a82741cc... git remote add norov https://github.com/norov/linux git fetch --no-tags norov find_bit_smallconst_v4 git checkout 1c7083bf4aab3b8d9dedc5155a5a82741cc161bc # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=sh 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 include/asm-generic/bitops/le.h:5, from arch/sh/include/asm/bitops.h:65, from include/linux/bitops.h:32, from include/linux/kernel.h:11, from include/asm-generic/bug.h:20, from arch/sh/include/asm/bug.h:112, from include/linux/bug.h:5, from include/linux/page-flags.h:10, from kernel/bounds.c:10: include/asm-generic/bitops/find.h: In function 'find_last_bit': 164 | return val ? __fls(val) : size; | ^~~~~ | __ffs In file included from arch/sh/include/asm/bitops.h:68, from include/linux/bitops.h:32, from include/linux/kernel.h:11, from include/asm-generic/bug.h:20, from arch/sh/include/asm/bug.h:112, from include/linux/bug.h:5, from include/linux/page-flags.h:10, from kernel/bounds.c:10: include/asm-generic/bitops/__fls.h: At top level: 13 | static __always_inline unsigned long __fls(unsigned long word) | ^~~~~ In file included from include/asm-generic/bitops/le.h:5, from arch/sh/include/asm/bitops.h:65, from include/linux/bitops.h:32, from include/linux/kernel.h:11, from include/asm-generic/bug.h:20, from arch/sh/include/asm/bug.h:112, from include/linux/bug.h:5, from include/linux/page-flags.h:10, from kernel/bounds.c:10: include/asm-generic/bitops/find.h:164:16: note: previous implicit declaration of '__fls' was here 164 | return val ? __fls(val) : size; | ^~~~~ cc1: some warnings being treated as errors -- In file included from include/asm-generic/bitops/le.h:5, from arch/sh/include/asm/bitops.h:65, from include/linux/bitops.h:32, from include/linux/kernel.h:11, from include/asm-generic/bug.h:20, from arch/sh/include/asm/bug.h:112, from include/linux/bug.h:5, from include/linux/page-flags.h:10, from kernel/bounds.c:10: include/asm-generic/bitops/find.h: In function 'find_last_bit': 164 | return val ? __fls(val) : size; | ^~~~~ | __ffs In file included from arch/sh/include/asm/bitops.h:68, from include/linux/bitops.h:32, from include/linux/kernel.h:11, from include/asm-generic/bug.h:20, from arch/sh/include/asm/bug.h:112, from include/linux/bug.h:5, from include/linux/page-flags.h:10, from kernel/bounds.c:10: include/asm-generic/bitops/__fls.h: At top level: 13 | static __always_inline unsigned long __fls(unsigned long word) | ^~~~~ In file included from include/asm-generic/bitops/le.h:5, from arch/sh/include/asm/bitops.h:65, from include/linux/bitops.h:32, from include/linux/kernel.h:11, from include/asm-generic/bug.h:20, from arch/sh/include/asm/bug.h:112, from include/linux/bug.h:5, from include/linux/page-flags.h:10, from kernel/bounds.c:10: include/asm-generic/bitops/find.h:164:16: note: previous implicit declaration of '__fls' was here 164 | return val ? __fls(val) : size; | ^~~~~ cc1: some warnings being treated as errors make[2]: *** [scripts/Makefile.build:116: kernel/bounds.s] Error 1 make[2]: Target '__build' not remade because of errors. make[1]: *** [Makefile:1233: prepare0] Error 2 make[1]: Target 'prepare' not remade because of errors. make: *** [Makefile:215: __sub-make] Error 2 make: Target 'prepare' not remade because of errors. vim +164 include/asm-generic/bitops/find.h 149 150 #ifndef find_last_bit 151 /** 152 * find_last_bit - find the last set bit in a memory region 153 * @addr: The address to start the search at 154 * @size: The number of bits to search 155 * 156 * Returns the bit number of the last set bit, or size. 157 */ 158 static inline 159 unsigned long find_last_bit(const unsigned long *addr, unsigned long size) 160 { 161 if (small_const_nbits(size)) { 162 unsigned long val = *addr & BITS_FIRST(size - 1); 163 165 } 166 167 return _find_last_bit(addr, size); 168 } 169 #endif 170 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org