diff --git a/src/sgsn/gprs_gmm_fsm.c b/src/sgsn/gprs_gmm_fsm.c
index fac06f2..94ecb50 100644
--- a/src/sgsn/gprs_gmm_fsm.c
+++ b/src/sgsn/gprs_gmm_fsm.c
@@ -183,5 +183,5 @@
 
 static __attribute__((constructor)) void gmm_fsm_init(void)
 {
-	osmo_fsm_register(&gmm_fsm);
+	OSMO_ASSERT(osmo_fsm_register(&gmm_fsm) == 0);
 }