reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git/commit/?id=36e44186e0badfda499b65d4462c49783bf92314
        git remote add brgl https://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux.git
        git fetch --no-tags brgl gpio/for-next
        git checkout 36e44186e0badfda499b65d4462c49783bf92314
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=um olddefconfig
        make W=1 O=build_dir ARCH=um SHELL=/bin/bash