diff --git a/src/backend/statistics/mcv.c b/src/backend/statistics/mcv.c
index 136ebdd..75858e7 100644
--- a/src/backend/statistics/mcv.c
+++ b/src/backend/statistics/mcv.c
@@ -911,7 +911,7 @@ statext_mcv_serialize(MCVList *mcvlist, VacAttrStats **stats)
 	for (i = 0; i < mcvlist->nitems; i++)
 	{
 		MCVItem    *mcvitem = &mcvlist->items[i];
-		int			itemlen = ITEM_SIZE(dim);
+		int			itemlen PG_USED_FOR_ASSERTS_ONLY = ITEM_SIZE(dim);
 
 		/* don't write beyond the allocated space */
 		Assert(ptr <= (endptr - itemlen));