reproduce (this is a W=1 build):
        git remote add rcu https://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux.git
        git fetch rcu rcu/dev
        git checkout rcu/rcu/dev
        b4 shazam https://lore.kernel.org/r/20260529134004.396743-5-work@onurozkan.dev

        # clang-22 might not be officially released. Try a lower version if installation fails.
        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=$HOME/0day COMPILER=clang-22 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=x86_64 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang-22 ~/lkp-tests/kbuild/make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash drivers/nvme/target/ kernel/rcu/