diff --git a/mlir/include/mlir/Support/DebugAction.h b/mlir/include/mlir/Support/DebugAction.h
index 4dc04476b583e3..227d213b0ddac4 100644
--- a/mlir/include/mlir/Support/DebugAction.h
+++ b/mlir/include/mlir/Support/DebugAction.h
@@ -205,7 +205,8 @@ template <typename... ParameterTs> class DebugAction {
 
     /// Provide classof to allow casting between handler types.
     static bool classof(const DebugActionManager::HandlerBase *handler) {
-      return handler->getHandlerID() == TypeID::get<Handler>();
+      return handler->getHandlerID() ==
+             TypeID::get<DebugAction<ParameterTs...>::Handler>();
     }
   };
 
diff --git a/mlir/unittests/CMakeLists.txt b/mlir/unittests/CMakeLists.txt
index 2798c443cf98d7..21506862a302c7 100644
--- a/mlir/unittests/CMakeLists.txt
+++ b/mlir/unittests/CMakeLists.txt
@@ -11,7 +11,6 @@ add_subdirectory(ExecutionEngine)
 add_subdirectory(Interfaces)
 add_subdirectory(IR)
 add_subdirectory(Pass)
-add_subdirectory(Support)
 add_subdirectory(Rewrite)
 add_subdirectory(TableGen)
 add_subdirectory(Transforms)
diff --git a/mlir/unittests/Support/CMakeLists.txt b/mlir/unittests/Support/CMakeLists.txt
index fd1e66205c071f..6616a793ec12fb 100644
--- a/mlir/unittests/Support/CMakeLists.txt
+++ b/mlir/unittests/Support/CMakeLists.txt
@@ -7,4 +7,4 @@ add_mlir_unittest(MLIRSupportTests
 )
 
 target_link_libraries(MLIRSupportTests
-  PRIVATE MLIRSupport)
+  PRIVATE MLIRSupportIndentedOstream MLIRSupport)