diff --git a/src/Workspaces/Core/Portable/Workspace/Workspace.cs b/src/Workspaces/Core/Portable/Workspace/Workspace.cs
index 73a3c4e8a740..1fda815b1444 100644
--- a/src/Workspaces/Core/Portable/Workspace/Workspace.cs
+++ b/src/Workspaces/Core/Portable/Workspace/Workspace.cs
@@ -318,6 +318,7 @@ static Solution UnifyLinkedDocumentContents(Solution oldSolution, Solution newSo
             // now, for any changed document, ensure we go and make all links to it have the same text/tree.
             newSolution = UpdateExistingDocumentsToChangedDocumentContents(newSolution, changedDocumentIds, projectToSiblingFlavors);
 
+            // Free the ArrayBuilders in projectToSiblingFlavors.  The dictionary itself will be automatically freed at the end of this scope.
             projectToSiblingFlavors.FreeValues();
 
             return newSolution;