o Security fixes:

    - Try to leak less information about what relays a client is
      choosing to a side-channel attacker.  Previously, a Tor client
      would stop iterating through the list of available relays as
      soon as it had chosen one, thus leaking information about which
      relays it picked for a circuit to a timing attack.  (Tor is
      likely to still leak information about which relays it has
      chosen for a circuit to other processes on the same computer,
      through e.g. which cache lines it loads while building the
      circuit.)