diff --git a/ChangeLog b/ChangeLog
index 20436d7..f38c0cf 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -5,6 +5,10 @@
 Features
    * Add function pk_check_pair() to test if public and private keys match.
 
+Bugfix
+   * User set CFLAGS were ignore by Cmake with gcc (introduced in 1.3.9, found
+     by Julian Ospald).
+
 Changes
    * Use deterministic nonces for AEAD ciphers in TLS by default (possible to
      switch back to random with POLARSSL_SSL_AEAD_RANDOM_IV in config.h).