diff --git a/cmake/QtBuild.cmake b/cmake/QtBuild.cmake
index 025000c9770..fecaf2e831f 100644
--- a/cmake/QtBuild.cmake
+++ b/cmake/QtBuild.cmake
@@ -3515,7 +3515,7 @@ endfunction()
 function(qt_add_3rdparty_library target)
     # Process arguments:
     qt_parse_all_arguments(arg "qt_add_3rdparty_library"
-        "SHARED;MODULE;STATIC;INTERFACE;EXCEPTIONS;INSTALL"
+        "SHARED;MODULE;STATIC;INTERFACE;EXCEPTIONS;INSTALL;SKIP_AUTOMOC"
         "OUTPUT_DIRECTORY"
         "${__default_private_args};${__default_public_args}"
         ${ARGN}
@@ -3574,7 +3574,9 @@ function(qt_add_3rdparty_library target)
         OUTPUT_NAME "${INSTALL_CMAKE_NAMESPACE}${target}"
     )
 
-    qt_autogen_tools_initial_setup(${target})
+    if(NOT arg_SKIP_AUTOMOC)
+        qt_autogen_tools_initial_setup(${target})
+    endif()
 
     if(NOT arg_INTERFACE)
         # This property is used for super builds with static libraries. We use
diff --git a/src/3rdparty/harfbuzz-ng/CMakeLists.txt b/src/3rdparty/harfbuzz-ng/CMakeLists.txt
index 38381f747d8..967aac353d3 100644
--- a/src/3rdparty/harfbuzz-ng/CMakeLists.txt
+++ b/src/3rdparty/harfbuzz-ng/CMakeLists.txt
@@ -6,6 +6,7 @@
 
 qt_add_3rdparty_library(BundledHarfbuzz
     STATIC
+    SKIP_AUTOMOC # special case
     SOURCES
         hb-dummy.cc
         src/hb.h