From 57850f9d6d6cf2d745cdfcdecb4b55cd9088b898 Mon Sep 17 00:00:00 2001
From: Ulf Hermann <ulf.hermann@qt.io>
Date: Wed, 14 Apr 2021 14:00:20 +0200
Subject: [PATCH] Switch metatypes generation on by default for Qt modules

We need the metatypes for anything directly or indirectly exposed to
QML. Switching this on has no runtime overhead. For interface libraries
we cannot generate any metatypes, though.

Change-Id: I7b7f85bb4e16c28d00383c5c88b0f1c172c8d193
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
---
 cmake/QtModuleHelpers.cmake | 28 +++++++++++++++++++---------
 src/corelib/CMakeLists.txt  |  1 +
 2 files changed, 20 insertions(+), 9 deletions(-)

diff --git a/cmake/QtModuleHelpers.cmake b/cmake/QtModuleHelpers.cmake
index 95272d3932b..886e338b205 100644
--- a/cmake/QtModuleHelpers.cmake
+++ b/cmake/QtModuleHelpers.cmake
@@ -17,9 +17,10 @@
 function(qt_internal_add_module target)
     qt_internal_module_info(module "${target}")
 
+    # TODO: Remove GENERATE_METATYPES once it's not used anymore.
     # Process arguments:
     qt_parse_all_arguments(arg "qt_add_module"
-        "NO_MODULE_HEADERS;STATIC;DISABLE_TOOLS_EXPORT;EXCEPTIONS;INTERNAL_MODULE;NO_SYNC_QT;NO_PRIVATE_MODULE;HEADER_MODULE;GENERATE_METATYPES;NO_CONFIG_HEADER_FILE;SKIP_DEPENDS_INCLUDE;NO_ADDITIONAL_TARGET_INFO"
+        "NO_MODULE_HEADERS;STATIC;DISABLE_TOOLS_EXPORT;EXCEPTIONS;INTERNAL_MODULE;NO_SYNC_QT;NO_PRIVATE_MODULE;HEADER_MODULE;GENERATE_METATYPES;NO_GENERATE_METATYPES;NO_CONFIG_HEADER_FILE;SKIP_DEPENDS_INCLUDE;NO_ADDITIONAL_TARGET_INFO"
         "MODULE_INCLUDE_NAME;CONFIG_MODULE_NAME;PRECOMPILED_HEADER;CONFIGURE_FILE_PATH;${__default_target_info_args}"
         "${__default_private_args};${__default_public_args};${__default_private_module_args};QMAKE_MODULE_CONFIG;EXTRA_CMAKE_FILES;EXTRA_CMAKE_INCLUDES;NO_PCH_SOURCES" ${ARGN})
 
@@ -498,15 +499,24 @@ set(QT_CMAKE_EXPORT_NAMESPACE ${QT_CMAKE_EXPORT_NAMESPACE})")
     endif()
 
     # Generate metatypes
-    if (${arg_GENERATE_METATYPES})
-        set(metatypes_install_dir ${INSTALL_LIBDIR}/metatypes)
-        set(args)
-        if (NOT QT_WILL_INSTALL)
-            set(args COPY_OVER_INSTALL INSTALL_DIR "${QT_BUILD_DIR}/${metatypes_install_dir}")
-        else()
-            set(args INSTALL_DIR "${metatypes_install_dir}")
+    if(${arg_GENERATE_METATYPES})
+        # No mention of NO_GENERATE_METATYPES. You should not use it.
+        message(WARNING "GENERATE_METATYPES is on by default for Qt modules. Please remove the manual specification.")
+    endif()
+    if (NOT ${arg_NO_GENERATE_METATYPES})
+        get_target_property(target_type ${target} TYPE)
+        if (NOT target_type STREQUAL "INTERFACE_LIBRARY")
+            set(metatypes_install_dir ${INSTALL_LIBDIR}/metatypes)
+            set(args)
+            if (NOT QT_WILL_INSTALL)
+                set(args COPY_OVER_INSTALL INSTALL_DIR "${QT_BUILD_DIR}/${metatypes_install_dir}")
+            else()
+                set(args INSTALL_DIR "${metatypes_install_dir}")
+            endif()
+            qt6_extract_metatypes(${target} ${args})
+        elseif(${arg_GENERATE_METATYPES})
+            message(FATAL_ERROR "Meta types generation does not work on interface libraries")
         endif()
-        qt6_extract_metatypes(${target} ${args})
     endif()
     qt_internal_get_min_new_policy_cmake_version(min_new_policy_version)
     qt_internal_get_max_new_policy_cmake_version(max_new_policy_version)
diff --git a/src/corelib/CMakeLists.txt b/src/corelib/CMakeLists.txt
index 3b4fdd1b465..2af8854798c 100644
--- a/src/corelib/CMakeLists.txt
+++ b/src/corelib/CMakeLists.txt
@@ -32,6 +32,7 @@ endif()
 
 qt_internal_add_module(Core
     QMAKE_MODULE_CONFIG moc resources
+    NO_GENERATE_METATYPES # metatypes are extracted manually below
     EXCEPTIONS
     SOURCES
         global/archdetect.cpp