title: "Indirect modification of overloaded element of SplFixedArray has no effect"
body: <p>Why the following</p>
  
  <pre><code>$a = new SplFixedArray(5);
  $a[0] = array(1, 2, 3);
  $a[0][0] = 12345; // here
  var_dump($a);
  </code></pre>
  
  <p>produces</p>
  
  <pre><code>Notice: Indirect modification of overloaded element of SplFixedArray has no effect in &lt;file&gt; on line &lt;indicated&gt;
  </code></pre>
  
  <p>Is it a bug? How do you deal with multidimensional SplFixedArrays then? Any workarounds?</p>