reproduce (this is a W=1 build):
        git checkout c1acb21b32a3bb601453764c9eac9fc8fbb3a81d
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=x86_64 olddefconfig
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/ sound/