// file, then move it into place once we're done writing.  And we warn the
  // user if these moves are not known to be atomic.
  bool has_atomic_move = false;
  env->HasAtomicMove(persistent_cache_directory_, &has_atomic_move)
      .IgnoreError();
  if (!has_atomic_move) {
    LOG_EVERY_POW_2(WARNING)
        << "Filesystem for XLA persistent cache at "
        << persistent_cache_directory_