diff --git a/ndn-cpp/security/identity/identity-manager.cpp b/ndn-cpp/security/identity/identity-manager.cpp
index c5a7793..3faf94b 100644
--- a/ndn-cpp/security/identity/identity-manager.cpp
+++ b/ndn-cpp/security/identity/identity-manager.cpp
@@ -6,7 +6,7 @@
  * See COPYING for copyright and distribution information.
  */
 
-#if 1
+#if 1 // TODO: Remove this when we don't throw "not implemented".
 #include <stdexcept>
 #endif
 #include <ctime>