diff --git a/src/gprs_ms.c b/src/gprs_ms.c
index 739bbcd..4cab8e4 100644
--- a/src/gprs_ms.c
+++ b/src/gprs_ms.c
@@ -396,7 +396,7 @@
 
 /* Cleans up old MS being merged into a new one. Should be called with a
 ms_ref() taken to avoid use-after-free. */
-void ms_reset(struct GprsMs *ms)
+static void ms_reset(struct GprsMs *ms)
 {
 	LOGPMS(ms, DMS, LOGL_INFO, "Clearing MS object\n");
 	struct llist_item *pos;