reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/boqun/linux.git/commit/?id=8ca1287ecd53e1124d394449c78cab9ad9d1fe93
        git remote add boqun https://git.kernel.org/pub/scm/linux/kernel/git/boqun/linux.git
        git fetch --no-tags boqun rust-atomic-v3
        git checkout 8ca1287ecd53e1124d394449c78cab9ad9d1fe93
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        make W=1 O=build_dir ARCH=x86_64 olddefconfig
        make W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash rustfmtcheck