diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index c2feb92576..3ebf8caee9 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -9601,7 +9601,7 @@ KeepLogSeg(XLogRecPtr recptr, XLogSegNo *logSegNo)
 		/* Cap by max_slot_wal_keep_size ... */
 		if (max_slot_wal_keep_size_mb >= 0)
 		{
-			XLogRecPtr	slot_keep_segs;
+			uint64	slot_keep_segs;
 
 			slot_keep_segs =
 				ConvertToXSegs(max_slot_wal_keep_size_mb, wal_segment_size);