reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/broonie/ci.git/commit/?id=8f991eeead81d9908ba751d48d90969541e60142
        git remote add broonie-ci https://git.kernel.org/pub/scm/linux/kernel/git/broonie/ci.git
        git fetch --no-tags broonie-ci fileVkFsjG
        git checkout 8f991eeead81d9908ba751d48d90969541e60142
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=i386 olddefconfig
        make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash