diff --git a/content/mathml/content/src/nsMathMLElement.h b/content/mathml/content/src/nsMathMLElement.h
index 4c7048aa079..07fc0232adf 100644
--- a/content/mathml/content/src/nsMathMLElement.h
+++ b/content/mathml/content/src/nsMathMLElement.h
@@ -106,6 +106,8 @@ public:
   virtual nsIDOMNode* AsDOMNode() MOZ_OVERRIDE { return this; }
 
 protected:
+  virtual ~nsMathMLElement() {}
+
   virtual JSObject* WrapNode(JSContext *aCx) MOZ_OVERRIDE;
 
 private: