CMake: Fix qt6_generate_foreign_qml_types

We had the tst_qmlsplitlib test failing in in-source builds only,
because qt6_wrap_cpp is called on the generated sources and this sets
SKIP_AUTOMOC ON. Later in the build, the consumer of the
corresponding moc_XXX.cpp.json file errors out, because it cannot find
the file.

The test worked in out-of-source builds, because the paths of the
generated files were relative: add_custom_command generated the files in
the build dir. qt6_wrap_cpp got the relative paths and assumed them
relative to the source dir and did set SKIP_AUTOMOC on non-existent
source files. AUTOMOC took care of generating moc_XXX.cpp and
moc_XXX.cpp.json, and all was well.

Clearly, the consumer of the moc_XXX.cpp.json files expects them to be
generated by AUTOMOC.

Fix this by
- using absolute paths for the generated files to make sure
  target_sources gets the correct paths
- removing the qt6_wrap_cpp call

Pick-to: 6.5 6.4
Fixes: QTBUG-110117
Change-Id: I01bcd8e37f57cf30ea06a7dd1fd8844367b58a14
Reviewed-by: Alexey Edelev <alexey.edelev@qt.io>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

1 files changed, 10 insertions, 2 deletions

diff --git a/src/qml/Qt6QmlMacros.cmake b/src/qml/Qt6QmlMacros.cmake
index 90a53e77b1..fce7156a55 100644
--- a/src/qml/Qt6QmlMacros.cmake
+++ b/src/qml/Qt6QmlMacros.cmake
@@ -2302,8 +2302,17 @@ function(qt6_generate_foreign_qml_types source_target destination_qml_target)
         message(FATAL_ERROR "Need target metatypes.json file")
     endif()
 
+    get_target_property(automoc_enabled ${destination_qml_target} AUTOMOC)
+    if(NOT automoc_enabled)
+        message(FATAL_ERROR "qt6_generate_foreign_qml_types requires AUTOMOC to be enabled "
+            "on target '${destination_qml_target}'.")
+    endif()
+
     set(registration_files_base ${source_target}_${destination_qml_target})
-    set(additional_sources ${registration_files_base}.cpp ${registration_files_base}.h)
+    set(additional_sources
+        "${CMAKE_CURRENT_BINARY_DIR}/${registration_files_base}.cpp"
+        "${CMAKE_CURRENT_BINARY_DIR}/${registration_files_base}.h"
+    )
 
     _qt_internal_get_tool_wrapper_script_path(tool_wrapper)
     add_custom_command(
@@ -2324,7 +2333,6 @@ function(qt6_generate_foreign_qml_types source_target destination_qml_target)
     )
 
     target_sources(${destination_qml_target} PRIVATE ${additional_sources})
-    qt6_wrap_cpp(${additional_sources} TARGET ${destination_qml_target})
 endfunction()
 
 if(NOT QT_NO_CREATE_VERSIONLESS_FUNCTIONS)