src/ErrorHandler/ErrorHandler.php
public function onShutdown(Event $event)
    {
        if (!$this->registered) {
            return;
        }
        $error = $event['error'] ?: \error_get_last();
        if (!$error) {
            return;
        }
        if (\in_array($error['type'], $this->errCategories['fatal'])) {
            /*
                found in wild:
                @include(some_file_with_parse_error)
                which will trigger a fatal error (here we are),
                but error_reporting() will return 0 due to the @ operator
                unsupress fatal error here
            */
            \error_reporting(E_ALL | E_STRICT);
            $this->handleError($error['type'], $error['message'], $error['file'], $error['line']);
        }
        /*
            Find the fatal error/uncaught-exception and attach to shutdown event
        */
        foreach ($this->data['errors'] as $error) {
            if ($error['category'] === 'fatal') {
                $event['error'] = $error;
                break;
            }
        }
        return;
    }
public function onShutdown(Event $event)
    {
        if (!$this->registered) {
            return;
        }
        $error = $event['error'] ?: \error_get_last();
        if (!$error) {
            return;
        }
        if (\in_array($error['type'], $this->errCategories['fatal'])) {
            /*
                found in wild:
                @include(some_file_with_parse_error)
                which will trigger a fatal error (here we are),
                but error_reporting() will return 0 due to the @ operator
                unsupress fatal error here
            */
            \error_reporting(E_ALL | E_STRICT);
            $this->handleError($error['type'], $error['message'], $error['file'], $error['line']);
        }
        /*
            Find the fatal error/uncaught-exception and attach to shutdown event
        */
        foreach ($this->data['errors'] as $error) {
            if ($error['category'] === 'fatal') {
                $event['error'] = $error;
                break;
            }
        }
        return;
    }
php.shutdown event subscriber

Used to handle fatal errors

Test fatal error handling by publishing 'php.shutdown' event with error value

@param Event $event php.shutdown event

@return void