diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c
index 8cd10ab204..6b50a22832 100644
--- a/src/backend/utils/adt/datetime.c
+++ b/src/backend/utils/adt/datetime.c
@@ -1382,7 +1382,6 @@ DecodeDateTime(char **field, int *ftype, int nf,
 				if (type == IGNORE_DTF)
 					continue;
 
-				tmask = DTK_M(type);
 				switch (type)
 				{
 					case RESERV: