1 files changed, 5 insertions, 0 deletions
diff --git a/platform/lang-impl/src/com/intellij/util/indexing/containers/IdSet.java b/platform/lang-impl/src/com/intellij/util/indexing/containers/IdSet.java
index f09dea88c747..aec57a934ad1 100644
--- a/platform/lang-impl/src/com/intellij/util/indexing/containers/IdSet.java
+++ b/platform/lang-impl/src/com/intellij/util/indexing/containers/IdSet.java
@@ -79,5 +79,10 @@ public class IdSet extends TIntHashSet implements RandomAccessIntContainer {
     public boolean hasAscendingOrder() {
       return false;
     }
+
+    @Override
+    public ValueContainer.IntIterator createCopyInInitialState() {
+      return new IntSetIterator();
+    }
   }
 }