From 246b43d581a17dd9578553b0569b7fb2f2da8e85 Mon Sep 17 00:00:00 2001
From: Fabian Kosmale <fabian.kosmale@qt.io>
Date: Tue, 27 May 2025 11:30:37 +0200
Subject: [PATCH] cmake: Unify the set flags between AUTOMOC and qt_wrap_cpp

For AUTOMOC, we were missing the compiler flavor flag, as well as the
WIN32 define. While the latter has not caused any known issues yet, the
former is rather problematic for implementing __has_include in moc.

Note that this only applies in the case where the AUTOMOC flags are set
by us in a qt_ function like qt_add_excutable. Plain add_executable
won't benefit from it, but we already mention that Qt targets should not
use plain CMake functions.

This change is (indirectly) tested by the commit adding __has_include
support for moc.

Task-number: QTBUG-136097
Pick-to: 6.10 6.9 6.8
Change-Id: Ie2beb08a44a3a67e3bc363d9c1ba93b7d6a49133
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>
---
 cmake/QtAutogenHelpers.cmake     |  3 +++
 cmake/QtPublicCMakeHelpers.cmake | 12 ++++++++++++
 cmake/QtTargetHelpers.cmake      |  4 +++-
 src/corelib/Qt6CoreMacros.cmake  | 19 +++++++++++--------
 4 files changed, 29 insertions(+), 9 deletions(-)

diff --git a/cmake/QtAutogenHelpers.cmake b/cmake/QtAutogenHelpers.cmake
index 4bbc6266bf5..8aabb09e14a 100644
--- a/cmake/QtAutogenHelpers.cmake
+++ b/cmake/QtAutogenHelpers.cmake
@@ -166,6 +166,9 @@ function(qt_manual_moc result)
             set(metatypes_byproducts "${outfile}.json")
         endif()
 
+        _qt_internal_get_moc_compiler_flavor_flags(flavor_flags)
+        list(APPEND moc_parameters ${flavor_flags})
+
         if (TARGET Qt::Platform)
            get_target_property(_abi_tag Qt::Platform qt_libcpp_abi_tag)
            if (_abi_tag)
diff --git a/cmake/QtPublicCMakeHelpers.cmake b/cmake/QtPublicCMakeHelpers.cmake
index 2027a06174e..1cb6e5a2412 100644
--- a/cmake/QtPublicCMakeHelpers.cmake
+++ b/cmake/QtPublicCMakeHelpers.cmake
@@ -968,3 +968,15 @@ function(_qt_internal_append_cmake_configure_depends)
     endforeach()
     set_property(DIRECTORY PROPERTY CMAKE_CONFIGURE_DEPENDS "${configure_depends}")
 endfunction()
+
+function(_qt_internal_get_moc_compiler_flavor_flags out_var)
+    set(flags "")
+    if(WIN32)
+        list(APPEND flags -DWIN32)
+    endif()
+    if(MSVC)
+        list(APPEND flags --compiler-flavor=msvc)
+    endif()
+
+    set(${out_var} "${flags}" PARENT_SCOPE)
+endfunction()
diff --git a/cmake/QtTargetHelpers.cmake b/cmake/QtTargetHelpers.cmake
index 43c27f9f910..25f6ec07046 100644
--- a/cmake/QtTargetHelpers.cmake
+++ b/cmake/QtTargetHelpers.cmake
@@ -195,9 +195,11 @@ function(qt_internal_extend_target target)
                             ${private_visibility_option} ${arg_LINK_OPTIONS})
 
         if(NOT is_interface_lib)
+            _qt_internal_get_moc_compiler_flavor_flags(flavor_flags)
             set_property(TARGET "${target}" APPEND PROPERTY
-                AUTOMOC_MOC_OPTIONS "${arg_MOC_OPTIONS}"
+                AUTOMOC_MOC_OPTIONS "${arg_MOC_OPTIONS}" ${flavor_flags}
             )
+
             # Plugin types associated to a module
             if(NOT "x${arg_PLUGIN_TYPES}" STREQUAL "x")
                 qt_internal_add_plugin_types("${target}" "${arg_PLUGIN_TYPES}")
diff --git a/src/corelib/Qt6CoreMacros.cmake b/src/corelib/Qt6CoreMacros.cmake
index 11383661649..fd938f0b1c2 100644
--- a/src/corelib/Qt6CoreMacros.cmake
+++ b/src/corelib/Qt6CoreMacros.cmake
@@ -67,12 +67,8 @@ macro(_qt_internal_get_moc_flags _moc_flags)
         set(${_moc_flags} ${${_moc_flags}} "-D${_current}")
     endforeach()
 
-    if(WIN32)
-        set(${_moc_flags} ${${_moc_flags}} -DWIN32)
-    endif()
-    if (MSVC)
-        set(${_moc_flags} ${${_moc_flags}} --compiler-flavor=msvc)
-    endif()
+    _qt_internal_get_moc_compiler_flavor_flags(flavor_flags)
+    set(${_moc_flags} ${${_moc_flags}} ${flavor_flags})
 endmacro()
 
 # helper macro to set up a moc rule
@@ -96,6 +92,9 @@ function(_qt_internal_create_moc_command infile outfile moc_flags moc_options
         set(${out_json_file} "${extra_output_files}" PARENT_SCOPE)
     endif()
 
+    _qt_internal_get_moc_compiler_flavor_flags(flavor_flags)
+    list(APPEND _moc_parameters ${flavor_flags})
+
     if(moc_target)
         set(_moc_parameters_file ${_moc_parameters_file}$<$<BOOL:$<CONFIG>>:_$<CONFIG>>)
         set(targetincludes "$<TARGET_PROPERTY:${moc_target},INCLUDE_DIRECTORIES>")
@@ -832,12 +831,16 @@ function(qt6_finalize_target target)
         endif()
     endif()
 
+    get_target_property(is_immediately_finalized "${target}" _qt_is_immediately_finalized)
+    get_target_property(uses_automoc ${target} AUTOMOC)
+    if(uses_automoc)
+        _qt_internal_get_moc_compiler_flavor_flags(flavor_flags)
+        set_property(TARGET "${target}" APPEND PROPERTY AUTOMOC_MOC_OPTIONS ${flavor_flags})
+    endif()
     if(target_type STREQUAL "SHARED_LIBRARY" OR
         target_type STREQUAL "STATIC_LIBRARY" OR
         target_type STREQUAL "MODULE_LIBRARY" OR
         target_type STREQUAL "OBJECT_LIBRARY")
-        get_target_property(is_immediately_finalized "${target}" _qt_is_immediately_finalized)
-        get_target_property(uses_automoc ${target} AUTOMOC)
         if(uses_automoc AND NOT is_immediately_finalized)
             qt6_extract_metatypes(${target})
         endif()