diff --git a/fs/btrfs/ordered-data.h b/fs/btrfs/ordered-data.h
index 8e8e3c0..36e63f1 100644
--- a/fs/btrfs/ordered-data.h
+++ b/fs/btrfs/ordered-data.h
@@ -46,7 +46,7 @@
 	unsigned long len;
 	struct list_head list;
 	/* last field is a variable length array of btrfs_sector_sums */
-	struct btrfs_sector_sum sums;
+	struct btrfs_sector_sum sums[];
 };
 
 /*