reproduce:
        # apt-get install sparse
        # sparse version: v0.6.4-66-g0196afe1
        # https://github.com/smfrench/smb3-kernel/commit/6a4ca4deeba8a1080059a42b2f05df0fd1f53012
        git remote add smfrench-smb3 https://github.com/smfrench/smb3-kernel.git
        git fetch --no-tags smfrench-smb3 for-next
        git checkout 6a4ca4deeba8a1080059a42b2f05df0fd1f53012
        # 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=x86_64 olddefconfig
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=x86_64 SHELL=/bin/bash fs/smb/client/