title: Concurrency::critical_section build error: cannot access private member
body: <p>I can't build below code(vs2013) blocks and getting error <em>"error C2248: 'Concurrency::critical_section::critical_section' : cannot access private member declared in class 'Concurrency::critical_section'"</em> </p>
  
  <p>Anyone can help explain why this is happening? Thanks  </p>
  
  <pre><code>#include &lt;ppl.h&gt;
  
  class Class1{
  
  public: 
  
      concurrency::critical_section _cs;
      int f1;
      Class1(int f){ f1 = f; }
  };
  
  class Class2{
  
  public: 
      std::vector&lt;Class1&gt; v1;
      Class2(){ v1.push_back(Class1(1)); v1.push_back(Class1(2)); }
  };
  
  int _tmain(int argc, _TCHAR* argv[])
  {    
      Class2 c2();
  
      return 0;
  }
  </code></pre>