diff --git a/velox/dwio/common/MetadataFilter.h b/velox/dwio/common/MetadataFilter.h
index b44ae69cbd5..62b604b1440 100644
--- a/velox/dwio/common/MetadataFilter.h
+++ b/velox/dwio/common/MetadataFilter.h
@@ -49,9 +49,9 @@ class MetadataFilter {
   std::string toString() const;
 
  private:
-  class Node;
-  class AndNode;
-  class OrNode;
+  struct Node;
+  struct AndNode;
+  struct OrNode;
 
   std::shared_ptr<Node> root_;
 };
diff --git a/velox/exec/TaskStructs.h b/velox/exec/TaskStructs.h
index 4d046b118fc..5ceec37289b 100644
--- a/velox/exec/TaskStructs.h
+++ b/velox/exec/TaskStructs.h
@@ -27,7 +27,7 @@ class JoinBridge;
 class LocalExchangeMemoryManager;
 class MergeSource;
 class MergeJoinSource;
-class Split;
+struct Split;
 class SpillOperatorGroup;
 
 /// Corresponds to Presto TaskState, needed for reporting query completion.