diff --git a/src/backend/utils/init/miscinit.c b/src/backend/utils/init/miscinit.c
index f04ae80f10..d74b5ccb30 100644
--- a/src/backend/utils/init/miscinit.c
+++ b/src/backend/utils/init/miscinit.c
@@ -825,7 +825,7 @@ CreateLockFile(const char *filename, bool amPostmaster,
 		 */
 		if (isDDLock)
 		{
-			char	   *ptr = NULL;
+			char	   *ptr = buffer;
 			unsigned long id1,
 						id2;
 			int lineno;