diff --git a/cmake/modules/OptimizeHeaders.cmake b/cmake/modules/OptimizeHeaders.cmake
index 3651a6885..a9a79e92d 100644
--- a/cmake/modules/OptimizeHeaders.cmake
+++ b/cmake/modules/OptimizeHeaders.cmake
@@ -9,7 +9,6 @@ file(GLOB_RECURSE headers "${headers_directory}/*.h")
 set(unifdef_arguments
     # bootstrap
     -UQT_BOOTSTRAPPED
-    -UQT_MOC
     # not supported
     -UQT_NO_QOBJECT
     -UQT_NO_COMPRESS
diff --git a/src/tools/moc/CMakeLists.txt b/src/tools/moc/CMakeLists.txt
index 6e0b1589e..189f1baf8 100644
--- a/src/tools/moc/CMakeLists.txt
+++ b/src/tools/moc/CMakeLists.txt
@@ -1,4 +1,4 @@
-add_definitions(-DQT_MOC)
+# add_definitions()
 set(EXTRA_MOC_LIBS
     KtCore
     # possible pthread reference from the global static mutex used in qmetaobject_p.h