diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/window/WindowExec.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/window/WindowExec.scala
index 626f39d9e9..fede0f3e92 100644
--- a/sql/core/src/main/scala/org/apache/spark/sql/execution/window/WindowExec.scala
+++ b/sql/core/src/main/scala/org/apache/spark/sql/execution/window/WindowExec.scala
@@ -323,8 +323,6 @@ case class WindowExec(
         fetchNextRow()
 
         // Manage the current partition.
-        val inputFields = child.output.length
-
         val buffer: ExternalAppendOnlyUnsafeRowArray =
           new ExternalAppendOnlyUnsafeRowArray(inMemoryThreshold, spillThreshold)