diff --git a/libs/sysplugins/smarty_internal_templatecompilerbase.php b/libs/sysplugins/smarty_internal_templatecompilerbase.php
index 76c4e7e0..c461df53 100644
--- a/libs/sysplugins/smarty_internal_templatecompilerbase.php
+++ b/libs/sysplugins/smarty_internal_templatecompilerbase.php
@@ -30,7 +30,7 @@ abstract class Smarty_Internal_TemplateCompilerBase
      *
      * @var object
      */
-    public $parser;
+    public $parser = null;
 
     /**
      * hash for nocache sections
@@ -305,8 +305,20 @@ abstract class Smarty_Internal_TemplateCompilerBase
      */
     public $_capture_stack = array();
 
+    /**
+     * Saved source resource
+     *
+     * @var \Smarty_Template_Source
+     */
     private $savedSource = null;
 
+    /**
+     * Stack for {setfilter} {/setfilter}
+     *
+     * @var array
+     */
+    public $variable_filter_stack = array();
+
     /**
      * Strip preg pattern
      *