title: dlopen doesn't respect `RTLD_LOCAL`?
body: <p>I have <code>A.so</code>, which links to a particular versioned <code>libstdc++.so.6</code> at its own directory (via <code>rpath</code> set to <code>$ORIGIN</code>).</p>
  
  <p>If I <code>dlopen</code> <code>A.so</code> alone, it works fine.</p>
  
  <p>If I <code>dlopen</code> my system's <code>libstdc++.so.6</code> (which is of different version) in <code>RTLD_LOCAL</code> mode, and then <code>dlopen</code> <code>A.so</code></p>
  
  <pre><code>OSError: /usr/lib/x86_64-linux-gnu/libstdc++.so.6: version `GLIBCXX_3.4.20' not found (required by A.so)
  </code></pre>
  
  <p>Why doesn't dlopen respect <code>RTLD_LOCAL</code>?</p>