diff --git a/platform/util/src/com/intellij/util/containers/LongArrayList.java b/platform/util/src/com/intellij/util/containers/LongArrayList.java
index 9a6ae1a07541..c0c9bb42ff87 100644
--- a/platform/util/src/com/intellij/util/containers/LongArrayList.java
+++ b/platform/util/src/com/intellij/util/containers/LongArrayList.java
@@ -15,6 +15,7 @@
  */
 package com.intellij.util.containers;
 
+@Deprecated // use TLongArrayList instead
 public class LongArrayList implements Cloneable {
   private long[] myData;
   private int mySize;