[kbuild-all] [rcu:dev.2020.11.15a 38/47] ERROR: modpost: "poll_state_synchronize_srcu" undefined!

tree: https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git dev.2020.11.15a head: 0cbf40a040eee93f0060e7eebac98c91ef6af021 commit: 7d879f439ed440baf02e676a784e8fa68ca87109 [38/47] rcutorture: Add writer-side tests of polling grace-period API config: x86_64-randconfig-a013-20201116 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project c044709b8fbea2a9a375e4173a6bd735f6866c0c) 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/paulmck/linux-rcu.git/com... git remote add rcu https://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu.git git fetch --no-tags rcu dev.2020.11.15a git checkout 7d879f439ed440baf02e676a784e8fa68ca87109 # 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; Note: the rcu/dev.2020.11.15a HEAD 0cbf40a040eee93f0060e7eebac98c91ef6af021 builds fine. It only hurts bisectibility. All errors (new ones prefixed by >>, old ones prefixed by <<): --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org