title: std::vector<T> with function-local type
body: <p>Why does this</p>
  
  <pre><code>#include &lt;vector&gt;
  
  void f()
  {
      struct S
      {
          int first, second, third;
      };
  
      std::vector&lt;S&gt; vs;
  }
  </code></pre>
  
  <p>work with Visual C++ 2015, but not with g++ 4.8.4?</p>