title: golang bug with sprintf when giving string as argument to %09d
body: <p>Why doesnt this give a compile error, is it a bug in golang or do I miss something?</p>
  
  <pre><code>intPadded := fmt.Sprintf("%09d", "i am a string" )
  fmt.Println("bah" + intPadded)
  </code></pre>
  
  <p>when executed it gives</p>
  
  <pre><code>bah%!d(string=i am a string)
  </code></pre>