title: Symfony2: __toString() must not throw an exception
body: <p>I am deploying my Symfony2 application, but I am getting the following error:</p>
  
  <pre><code>FatalErrorException in classes.php line 0:
  Error: Method Symfony\Component\HttpFoundation\Request::__toString() must not throw an exception
  </code></pre>
  
  <p>Apache is slightly more descriptive, stating something about Monolog:</p>
  
  <pre><code> PHP Fatal error:  Method Symfony\\Component\\HttpFoundation\\Request::__toString() must not throw an exception in /my/path/vendor/monolog/monolog/src/Monolog/Formatter/NormalizerFormatter.php on line 0
  </code></pre>
  
  <p>It is also the only thing It is not clear to me how this is happening. Dev-environment on my local machine is running fine. </p>
  
  <p>I have tried to clear the prod cache, the composer cache and restarted apache service. I also did a fresh "composer install" after clearing its cache. </p>
  
  <p>Anyone has an idea how this can be solved? Am running Symfony v2.7.4.</p>