reproduce (this is a W=1 build):
        # https://github.com/cilium/linux/commit/2735913301fe3285613f291f594b1749487137aa
        git remote add cilium https://github.com/cilium/linux.git
        git fetch --no-tags cilium pr/netkit-iouring15
        git checkout 2735913301fe3285613f291f594b1749487137aa

        git clone https://github.com/intel/lkp-tests.git ~/lkp-tests
        # apt-get install llvm-dev

        # save the config file
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 ARCH=i386 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 ARCH=i386 
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 headers
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-20 ~/lkp-tests/kbuild/make.cross W=1 -C tools/testing/selftests