错误500和PHP崩溃

Question

我在页面上有这个

<section class="sidebar">                    
    <ul class="sidebar-menu">
        <?php require_once 'includes/left.php'; ?>
    </ul>
</section>

在此left.php我有：

<?php 

    if ($_SESSION['role'] == 1){
        echo'                       
             <li class="active">
                  <a href="index.php">
                       <i class="fa fa-dashboard"></i> <span>Home</span>
                  </a>
             </li>
             <li class="treeview">
                  <a href="#">
                      <i class="fa fa-user"></i>
                          <span>MainMenu</span>
                      <i class="fa fa-angle-left pull-right"></i>
                  </a>
                  <ul class="treeview-menu">
                       <li><a href=""><i class="fa fa-angle-double-right"></i> Role_1.1</a></li>  
                       <li><a href=""><i class="fa fa-angle-double-right"></i> Role_1.2</a></li> 
                       <li><a href=""><i class="fa fa-angle-double-right"></i> Role_1.3</a></li>  
                       <li><a href=""><i class="fa fa-angle-double-right"></i> Role_1.4</a></li> 
                       <li><a href=""><i class="fa fa-angle-double-right"></i> Role_1.5</a></li>  
                       <li><a href=""><i class="fa fa-angle-double-right"></i> Role_1.6</a></li> 
                   </ul>                            
              </li>                        
              <li class="treeview">
                   <a href="#">
                       <i class="fa fa-file"></i>
                       <span>MainMenu2</span>
                       <i class="fa fa-angle-left pull-right"></i>
                   </a>
                   <ul class="treeview-menu">';
                       $pdo = Database::connect();
                       $sql = $pdo->prepare("SELECT form.field_name, form.group_id, form.field_id, cat.form_field_cat_name, cat.group_id
                            FROM form_fields form JOIN form_fields_category cat
                            ON form.group_id = cat.group_id
                            WHERE form.group_id = cat.group_id
                            GROUP BY form.group_id "); 
                $sql->execute();
                $rows = $sql->fetchAll();

                $html = [];

                foreach ($rows as $row) {              
                     $html [] = '<li><a href=""><i class="fa fa-angle-double-right"></i> Role_1 "' . $row['form_field_cat_name'] . '"</a></li>';               
                }
                   echo join("", $html); 
                   Database::disconnect();                  
        }   
        elseif ($_SESSION['role'] == 2)
        {
            echo '  
                <li class="active">
                    <a href="index.php">
                        <i class="fa fa-dashboard"></i> <span>Home</span>
                    </a>
                </li> 
                <li class="treeview">
                    <a href="#">
                        <i class="fa fa-user"></i>
                        <span>MainMenu</span>
                        <i class="fa fa-angle-left pull-right"></i>
                    </a>
                    <ul class="treeview-menu">
                       <li><a href=""><i class="fa fa-angle-double-right"></i> Role_1.3</a></li>  
                       <li><a href=""><i class="fa fa-angle-double-right"></i> Role_1.4</a></li> 
                       <li><a href=""><i class="fa fa-angle-double-right"></i> Role_1.5</a></li>  
                       <li><a href=""><i class="fa fa-angle-double-right"></i> Role_1.6</a></li> 
                    </ul>
                </li>                      
                <li class="treeview">
                     <a href="#">
                           <i class="fa fa-file"></i>
                           <span>MainMenu2</span>
                           <i class="fa fa-angle-left pull-right"></i>
                      </a>
                      <ul class="treeview-menu">';
                          $pdo = Database::connect();
                          $sql = $pdo->prepare("SELECT form.field_name, form.group_id, form.field_id, cat.form_field_cat_name, cat.group_id
                            FROM form_fields form JOIN form_fields_category cat
                            ON form.group_id = cat.group_id
                            WHERE form.group_id = cat.group_id
                            GROUP BY form.group_id "); 

                          $sql->execute();
                          $rows = $sql->fetchAll();

                          $html = [];

                          foreach ($rows as $row) {            
                               $html [] = '<li><a href=""><i class="fa fa-angle-double-right"></i> Role_2 "' . $row['form_field_cat_name'] . '"</a></li>';             
                          }

                           echo join("", $html); 
                           Database::disconnect();                                                      
        }

在这个left.php我只有2个菜单，根据用户角色，我会显示哪个菜单适合他/她。问题是我的主机在运行页面时向我显示错误500。并且托管错误日志中的问题是

EACCELERATOR: PHP crashed 

当我删除此include 'includes/left.php'页面正常运行时。有人能解释一下导致这个错误的原因吗？ left.php中有什么问题？