diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map
index 96f615e..19ebb5b 100644
--- a/src/gsm/libosmogsm.map
+++ b/src/gsm/libosmogsm.map
@@ -25,6 +25,7 @@
 abis_nm_ipa_magic;
 
 osmo_sitype_strs;
+osmo_c4;
 bitvec_add_range1024;
 comp128;
 dbm2rxlev;