diff --git a/osx/auto-update/auto-update.h b/osx/auto-update/auto-update.h
index 4313641..86068c8 100644
--- a/osx/auto-update/auto-update.h
+++ b/osx/auto-update/auto-update.h
@@ -24,6 +24,7 @@
 class AutoUpdate
 {
 public:
+  virtual ~AutoUpdate() {};
   virtual void checkForUpdates() = 0;
 };
 #endif
diff --git a/osx/auto-update/sparkle-auto-update.h b/osx/auto-update/sparkle-auto-update.h
index dc54bb1..1a19b9c 100644
--- a/osx/auto-update/sparkle-auto-update.h
+++ b/osx/auto-update/sparkle-auto-update.h
@@ -29,7 +29,7 @@
 {
 public:
   SparkleAutoUpdate (const QString &url);
-  ~SparkleAutoUpdate ();
+  virtual ~SparkleAutoUpdate ();
   virtual void checkForUpdates();
 private:
   class Private;