Hi Gioh,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linux/master]
[also build test WARNING on linus/master next-20210401]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Gioh-Kim/lib-string-Introduce-sysfs_streqcase/20210402-174251
base:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 5e46d1b78a03d52306f21f77a4e4a144b6d31486
config: mips-randconfig-r006-20210402 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project b23a314146956dd29b719ab537608ced736fc036)
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/0day-ci/linux/commit/b18d0dc7264473a4023926c510a67adfd7eaf119
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Gioh-Kim/lib-string-Introduce-sysfs_streqcase/20210402-174251
        git checkout b18d0dc7264473a4023926c510a67adfd7eaf119
        # 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@intel.com>

All warnings (new ones prefixed by >>):

>> lib/string.c:723:6: warning: no previous prototype for function 'sysfs_streqcase' [-Wmissing-prototypes]
   bool sysfs_streqcase(const char *s1, const char *s2)
        ^
   lib/string.c:723:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
   bool sysfs_streqcase(const char *s1, const char *s2)
   ^
   static 
   1 warning generated.


vim +/sysfs_streqcase +723 lib/string.c

   716	
   717	/**
   718	 * sysfs_streqcase - same to sysfs_streq and case insensitive
   719	 * @s1: one string
   720	 * @s2: another string
   721	 *
   722	 */
 > 723	bool sysfs_streqcase(const char *s1, const char *s2)
   724	{
   725		while (*s1 && tolower(*s1) == tolower(*s2)) {
   726			s1++;
   727			s2++;
   728		}
   729	
   730		if (*s1 == *s2)
   731			return true;
   732		if (!*s1 && *s2 == '\n' && !s2[1])
   733			return true;
   734		if (*s1 == '\n' && !s1[1] && !*s2)
   735			return true;
   736		return false;
   737	}
   738	EXPORT_SYMBOL(sysfs_streqcase);
   739	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org