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/tip/tip.git/commit/?id=9262ee6499954dd387e4507e03b84512ab100706
        git remote add tip https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git
        git fetch --no-tags tip WIP.x86/core
        git checkout 9262ee6499954dd387e4507e03b84512ab100706
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-7.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=arm64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-7.5.0 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=arm64 prepare