reproduce (this is a W=1 build):
        git remote add ceph-client https://github.com/ceph/ceph-client.git
        git fetch ceph-client for-linus
        git checkout ceph-client/for-linus
        b4 shazam https://lore.kernel.org/r/20251203154625.2779153-5-amarkuze@redhat.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 arch/x86/ block/ drivers/ fs/ kernel/ lib/ mm/ net/ security/ sound/