title: False warning for placement new?
body: <p>I have the following code:</p>
  
  <pre><code>#include "type_traits"
  #include &lt;new&gt;
  
  
  void foo()
  {
      std::aligned_storage&lt;10,alignof(long)&gt; storage;
      new (&amp;storage) int(12);
  }
  </code></pre>
  
  <p>I have some storage defined (with length 10 bytes), and I am placement <code>new</code>ing an <code>int</code> into that location</p>
  
  <p>gcc 7.3 gives the following warning:</p>
  
  <pre><code>&lt;source&gt;:10:10: warning: placement new constructing an object of type 'int' and size '4' in a region of type 'std::aligned_storage&lt;10, 8&gt;' and size '1' [-Wplacement-new=]
       new (&amp;storage) int(12);
  </code></pre>
  
  <p>If I am not incorrect this warning is incorrect.  Am I missing something here or is this warning spurious?</p>