diff --git a/cmake/QtBuild.cmake b/cmake/QtBuild.cmake
index a1b044b97d4..6f325adfb48 100644
--- a/cmake/QtBuild.cmake
+++ b/cmake/QtBuild.cmake
@@ -1462,9 +1462,12 @@ function(qt_add_module target)
     # Handle cases like QmlDevTools which do not have their own headers, but rather borrow them
     # from another module.
     if(NOT arg_NO_SYNC_QT AND NOT arg_NO_MODULE_HEADERS)
-        list(APPEND private_includes
-                    "$<BUILD_INTERFACE:${module_include_dir}/${PROJECT_VERSION}>"
-                    "$<BUILD_INTERFACE:${module_include_dir}/${PROJECT_VERSION}/${module}>")
+        # Don't include private headers unless they exist, aka syncqt created them.
+        if(module_headers_private)
+            list(APPEND private_includes
+                        "$<BUILD_INTERFACE:${module_include_dir}/${PROJECT_VERSION}>"
+                        "$<BUILD_INTERFACE:${module_include_dir}/${PROJECT_VERSION}/${module}>")
+        endif()
 
         list(APPEND public_includes
                     # For the syncqt headers