title: mongodump error on Mac OS X Sierra
body: <p>I tried to dump a tiny database for testing purposes using the following command:</p>
  
  <pre><code>mongodump --db demo
  </code></pre>
  
  <p>There was no output, but after around half an hour I got multiple error messages in my console:</p>
  
  <pre><code>...
  fatal error: systemstack called from unexpected goroutine
  fatal error: systemstack called from unexpected goroutine
  fatal error: systemstack called from unexpected goroutine
  fatal error: systemstack called from unexpected goroutine
  fatal error: systemstack called from unexpected goroutine
  fatal error: systemstack called from unexpected goroutine
  fatal error: systemstack called from unexpected goroutine
  fatal error: systemstack called from unexpected goroutine
  fatal error: systemstack called from unexpected goroutine
  ...
  </code></pre>
  
  <p>Not sure what does it mean, any help is highly appreciated. Thanks.</p>