diff --git a/KeyUtil.h b/KeyUtil.h
index b4115f4..7ee6725 100644
--- a/KeyUtil.h
+++ b/KeyUtil.h
@@ -33,7 +33,7 @@
                            const std::string& key_path, const std::string& tmp_path,
                            std::string* key_ref);
 bool retrieveKey(bool create_if_absent, const std::string& key_path, const std::string& tmp_path,
-                 KeyBuffer* key);
+                 KeyBuffer* key, bool keepOld = true);
 
 }  // namespace vold
 }  // namespace android