diff --git a/include/openbsc/gsm_data_shared.h b/include/openbsc/gsm_data_shared.h
index 0790807..60da2e5 100644
--- a/include/openbsc/gsm_data_shared.h
+++ b/include/openbsc/gsm_data_shared.h
@@ -899,7 +899,7 @@
 };
 
 
-struct gsm_bts *gsm_bts_alloc(void *talloc_ctx);
+struct gsm_bts *gsm_bts_alloc(void *talloc_ctx, uint8_t bts_num);
 struct gsm_bts *gsm_bts_num(struct gsm_network *net, int num);
 
 struct gsm_bts_trx *gsm_bts_trx_alloc(struct gsm_bts *bts);