diff --git a/ChangeLog b/ChangeLog
index 8eab14b..daac959 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -15,6 +15,8 @@
    * Add explicit integer to enumeration type casts to example program
      programs/pkey/gen_key which previously led to compilation failure
      on some toolchains. Reported by phoenixmcallister. Fixes #2170.
+   * Run the AD too long test only if MBEDTLS_CCM_ALT is not defined.
+     Raised as a comment in #1996.
 
 = mbed TLS 2.7.8 branch released 2018-11-30