possible values. Since fixing this is a breaking
          change and was only approached quite late in the release cycle with little
          discussion it's opt-in for now. This, or something like it, will become
          the default in a future version.
        </li></ul></div>
<h3>
<a name="hash.changes.h13"></a>
      <span class="phrase"><a name="hash.changes.boost_1_46_0"></a></span><a class="link" href="changes.html#hash.changes.boost_1_46_0">Boost
      1.46.0</a>
    </h3>
<div class="itemizedli