1 files changed, 4 insertions, 1 deletions
diff --git a/src/mongo/db/collection_index_builds_tracker.cpp b/src/mongo/db/collection_index_builds_tracker.cpp
index 58b3fef7b1b..9ef10722691 100644
--- a/src/mongo/db/collection_index_builds_tracker.cpp
+++ b/src/mongo/db/collection_index_builds_tracker.cpp
@@ -49,7 +49,10 @@ void CollectionIndexBuildsTracker::addIndexBuild(
     invariant(replIndexBuildState->indexNames.size());
     for (auto& indexName : replIndexBuildState->indexNames) {
         // Ensure that a new entry is added.
-        invariant(_buildStateByIndexName.emplace(indexName, replIndexBuildState).second);
+        invariant(_buildStateByIndexName.emplace(indexName, replIndexBuildState).second,
+                  str::stream() << "index build state for " << indexName
+                                << " already exists. Collection: "
+                                << replIndexBuildState->collectionUUID);
     }
 }