diff --git a/glib/gdatetime.c b/glib/gdatetime.c
index 745a32a9d..bad4ded3f 100644
--- a/glib/gdatetime.c
+++ b/glib/gdatetime.c
@@ -2220,7 +2220,7 @@ format_ampm (GDateTime *datetime,
              gboolean   uppercase)
 {
   const gchar *ampm;
-  gchar       *tmp, *ampm_dup;
+  gchar       *tmp = NULL, *ampm_dup;
   gsize        len;
 
   ampm = GET_AMPM (datetime);