reproduce (this is a W=1 build):
        git checkout e04c78d86a9699d136910cfc0bdcf01087e3267e
        b4 shazam https://lore.kernel.org/r/20250622125802.3224264-4-gary@kernel.org
        # 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 CLIPPY=1 rustdoc