ace: normal">BOOST_CLASS_TRACKING</code> that 
  was inserted. Now the second trap is avoided, But damn - the first trap is 
  popping up again. Eventually, after some code restructuring, the differing
  requirements of serializating <code style="white-space: normal">construct_from</code>
  are reconciled.
</ol>
Note that in this second scenario
<ul>
  <li>all errors are trapped at compile time.
  <li>no invalid archives are created.
  <li>no data is lost.
  <li>no runtime errors occur.
</ul>

It's true tha