title: What does //**/ mean?
body: <p>I have got snippet of old c-code with that lines (result is just slash sign):</p>
  
  <pre><code>putchar('/' //**/ 
      1 / 1 /'\1');
  </code></pre>
  
  <p>Can anyone explain this snippet? What does this symbols mean?</p>
  
  <p>P.S. By the way it compiles well with std=c89 flag in gcc, but not with std=c99. </p>