reproduce:
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # apt-get install sparse
        # sparse version: v0.6.4-66-g0196afe1
        # https://github.com/intel-lab-lkp/linux/commit/4f1a617439815db88b1366782a6575c9664e8a24
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review xur-google-com/kbuild-distributed-build-support-for-Clang-ThinLTO/20250522-053726
        git checkout 4f1a617439815db88b1366782a6575c9664e8a24
        # 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=arm64 olddefconfig
        ~/lkp-tests/kbuild/make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__ -fmax-errors=unlimited -fmax-warnings=unlimited' O=build_dir ARCH=arm64 SHELL=/bin/bash mm/