title: Pure virtual destructor in C++
body: <p>Is it wrong to write:</p>
  
  <pre><code>class A {
  public:
      virtual ~A() = 0;
  };
  </code></pre>
  
  <p>for an abstract base class?</p>
  
  <p>At least that compiles in MSVC... Will it crash at run time?</p>