reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git/commit/?id=1ee5d3698ee66fa1cf2ed0b874caa8dcd59c6c7f
        git remote add mszeredi-fuse https://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git
        git fetch --no-tags mszeredi-fuse for-next
        git checkout 1ee5d3698ee66fa1cf2ed0b874caa8dcd59c6c7f
        # apt-get install llvm-dev

        # save the config file
        make W=1 ARCH=i386 olddefconfig
        make W=1 ARCH=i386 
        make W=1 headers_install
        make W=1 -C tools/testing/selftests