title: c++11: Array bound is not an integer constant before a token
body: <p>I have seen this <a href="https://stackoverflow.com/questions/11269623/g-array-bound-is-not-an-integer-constant">question</a>, but the solution provided there doesn't solve the issue.</p>
  
  <pre><code>static int num_instances; 
  std::vector&lt;SomeClass::FunctionWithinTheClass&gt; *mem[num_instances];
  </code></pre>
  
  <p><code>SomeClass::FunctionWithinTheClass *mem[num_instances];</code> //Even this raises an error</p>
  
  <p>the value <code>num_instances</code> is obtained by reading a configuration file.</p>
  
  <p>The error I get is :
  <code>array bound is not an integer constant before ‘]’ token</code></p>
  
  <p>This is strange because the value <code>num_instances</code> is fixed at compile time.</p>