reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git/commit/?id=a7631399e1db94d34d3cc5bae11e1bfcbb02db30
        git remote add frederic-dynticks https://git.kernel.org/pub/scm/linux/kernel/git/frederic/linux-dynticks.git
        git fetch --no-tags frederic-dynticks timers/anna
        git checkout a7631399e1db94d34d3cc5bae11e1bfcbb02db30
        # 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 kernel/time/