diff --git a/glib/gtimezone.c b/glib/gtimezone.c
index ce42f5099..07f50bfd8 100644
--- a/glib/gtimezone.c
+++ b/glib/gtimezone.c
@@ -205,7 +205,7 @@ g_time_zone_ref (GTimeZone *tz)
  *  - hh is 00 to 23
  *  - mm is 00 to 59
  */
-gboolean
+static gboolean
 parse_time (const gchar *time,
             gint32      *offset)
 {