diff --git a/src/backend/utils/sort/logtape.c b/src/backend/utils/sort/logtape.c
index b97414c751..c361e47cee 100644
--- a/src/backend/utils/sort/logtape.c
+++ b/src/backend/utils/sort/logtape.c
@@ -391,7 +391,7 @@ ltsGetFreeBlock(LogicalTapeSet *lts)
 {
 	long	   *heap = lts->freeBlocks;
 	long		blocknum;
-	int			heapsize;
+	long		heapsize;
 	unsigned long pos;
 
 	/* freelist empty; allocate a new block */