reproduce:
        # apt-get install sparse
        # sparse version: v0.6.4-66-g0196afe1
        # https://github.com/intel-lab-lkp/linux/commit/ebe0e86fd8eaab94db2720ad59c977e527026b77
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Harry-Wentland/drm-Add-helper-for-conversion-from-signed-magnitude/20240820-050138
        git checkout ebe0e86fd8eaab94db2720ad59c977e527026b77
        # 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=um olddefconfig
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=um SHELL=/bin/bash drivers/gpu/drm/tests/