title: GCC 4.4/4.5 unique_ptr not work for unordered_set/unordered_map
body: <p>Is there any place I can confirm this?  I am not sure if it is the problem of GCC or my code.  For example, the following code doesn't compile:</p>
  
  <pre><code>#include &lt;unordered_set&gt;
  #include &lt;memory&gt;
  using namespace std;
  
  int main() {
      unordered_set&lt;unique_ptr&lt;int&gt; &gt; s;
      unique_ptr&lt;int&gt; p(new int(0));
      s.insert(move(p));
      return 0;
  }
  </code></pre>
  
  <p>The error message is too big and I don't want to put here.  GCC version is 4.5.3, compiling flag is -std=gnu++0x.  Also tested on 4.4.5.</p>