diff --git a/openbsc/tests/channel/channel_test.c b/openbsc/tests/channel/channel_test.c
index 759001c..32c7168 100644
--- a/openbsc/tests/channel/channel_test.c
+++ b/openbsc/tests/channel/channel_test.c
@@ -76,6 +76,7 @@
 void nm_state_event() {}
 void input_event() {}
 void sms_alloc() {}
+void gsm_net_update_ctype(struct gsm_network *network) {}
 
 struct tlv_definition nm_att_tlvdef;