title: not enough variables to fit a sentinel
body: <p>According to <a href="http://www.linuxonly.nl/docs/2/2_Sentinel_warning_missing_sentinel_in_function_call.html" rel="noreferrer">exec reference</a>, calls to exec (or stack checking vararg functions in general) requires a <code>(char*)NULL</code> aka 0 at the end of the parameter list. GCC, however, is complaining about the following code</p>
  
  <pre><code>char cmdFullPath[4096]; //yes this 4096 thing is bad coding practice 
  ...
  execl(cmdFullPath, (char*)NULL);
  
  //warning: not enough variable arguments to fit a sentinel
  </code></pre>
  
  <p>Anyone know what's wrong?</p>