reproduce:
        # apt-get install sparse
        # sparse version: v0.6.4-66-g0196afe1
        # https://github.com/rgushchin/linux/commit/bb7dddcd85b885a163916d548d1907c89771fd67
        git remote add rgushchin https://github.com/rgushchin/linux.git
        git fetch --no-tags rgushchin memcontrol_v1.rfc
        git checkout bb7dddcd85b885a163916d548d1907c89771fd67
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=i386 olddefconfig
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=i386 SHELL=/bin/bash mm/