reproduce:
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # apt-get install sparse
        # sparse version: v0.6.4-61-g09411a7a-dirty
        # https://github.com/jimc/linux/commit/f8d052f79bf3d7d6a368d0618852557817f74b4a
        git remote add jimc https://github.com/jimc/linux.git
        git fetch --no-tags jimc dyndbg_trace_v4_2
        git checkout f8d052f79bf3d7d6a368d0618852557817f74b4a
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        ~/lkp-tests/kbuild/make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=powerpc olddefconfig
        ~/lkp-tests/kbuild/make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=powerpc SHELL=/bin/bash