reproduce:
        # apt-get install sparse
        # sparse version: v0.6.4-66-g0196afe1
        # https://github.com/jimc/linux/commit/dc75936e9a1db05417181e3707b9179624d2b689
        git remote add jimc https://github.com/jimc/linux.git
        git fetch --no-tags jimc dyndbg_trace_v4_5e
        git checkout dc75936e9a1db05417181e3707b9179624d2b689
        # 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 drivers/dma/ drivers/mtd/ fs/affs/ fs/ext4/