title: Deprecation warning not catchable in PHP 7.4
body: <p>In PHP 7.4.0 I see the following warning:<br>
  <code>Deprecated: Array and string offset access syntax with curly braces is deprecated in ...</code><br>
  My error / exception handlers are not able to catch and log them.</p>
  
  <p><strong>Example:</strong></p>
  
  <pre><code>&lt;?php
      set_error_handler(function ($errNo, $errStr) {
          echo "set_error_handler: " . $errStr;
      });
  
      set_exception_handler(function ($exception) {
          echo "set_exception_handler: " . $exception-&gt;getMessage();
      });
  
      $b = 'test';
      $a = $b{1};
  </code></pre>
  
  <p>The warning is still displayed in the normal output and none of the two handlers is called.</p>
  
  <p>I want to log all errors, exceptions and warnings in my own log but this warning is not being catched by the handlers. Is there a reason for this or a solution to catch and log everything PHP is complaining about (have no access to the servers Apache/PHP log)?</p>