reproduce (this is a W=1 build):
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # https://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux.git/commit/?id=ae99e2e456aca980ec40e20ac1ca7e079330f058
        git remote add jlayton https://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux.git
        git fetch --no-tags jlayton uek-localio
        git checkout ae99e2e456aca980ec40e20ac1ca7e079330f058
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=x86_64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash arch/x86/kernel/cpu/ block/