reproduce (this is a W=1 build):
        git remote add rppt-memblock https://git.kernel.org/pub/scm/linux/kernel/git/rppt/memblock.git
        git fetch rppt-memblock for-next
        git checkout rppt-memblock/for-next
        b4 shazam https://lore.kernel.org/r/20251001011941.1513050-3-jasonmiu@google.com
        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=x86_64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash lib/