tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: 3e14f70c05cda4794901ed8f976de3a88deebcc0 commit: 622c9ff2b804a1de896e757f8fe3a71fcef2941b [5068/5074] kasan, mm: allow cache merging with no metadata config: x86_64-randconfig-a003-20201111 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 874b0a0b9db93f5d3350ffe6b5efda2d908415d0) 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 x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commi... git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch --no-tags linux-next master git checkout 622c9ff2b804a1de896e757f8fe3a71fcef2941b # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 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 >>): slab_flags_t __kasan_never_merge(slab_flags_t flags) ^ mm/kasan/common.c:89:1: note: declare 'static' if the function is not intended to be used outside of this translation unit slab_flags_t __kasan_never_merge(slab_flags_t flags) ^ static 1 warning generated. vim +/__kasan_never_merge +89 mm/kasan/common.c 84 85 /* 86 * Only allow cache merging when stack collection is disabled and no metadata 87 * is present. 88 */ 90 { 91 if (kasan_stack_collection_enabled()) 92 return flags; 93 return flags & ~SLAB_KASAN; 94 } 95 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org