CMake: Use correct MSVC runtime library for Qt object libraries

If Qt was configured with -static-runtime which implies MultiThreaded
-MT flag, the plugin initializer object libraries were still compiled
with the default -MD flag.

When an application linked to Qt, that caused linking to fail with
mismatched symbol errors between the application symbols and the
plugin initializer object library symbols.

Make sure to set the MSVC_RUNTIME_LIBRARY property on both plugin
initializer and resource object libraries, depending on the value of
QT_FEATURE_static_runtime.

We did set the property for resources added by
qt_internal_add_resource, but not for the resource created by
the public qt6_add_resources counterpart.

Pick-to: 6.2
Fixes: QTBUG-95043
Change-Id: Ia543cd0241db94a12080be2655ad420fe9ad3f24
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>

4 files changed, 14 insertions, 8 deletions

diff --git a/cmake/QtPublicPluginHelpers.cmake b/cmake/QtPublicPluginHelpers.cmake
index 919aee10c6..a765157f5f 100644
--- a/cmake/QtPublicPluginHelpers.cmake
+++ b/cmake/QtPublicPluginHelpers.cmake
@@ -243,6 +243,7 @@ function(__qt_internal_add_static_plugin_init_object_library
         # Core provides the symbols needed by Q_IMPORT_PLUGIN.
         ${QT_CMAKE_EXPORT_NAMESPACE}::Core
     )
+    _qt_internal_set_up_static_runtime_library("${plugin_init_target}")
 
     set_property(TARGET ${plugin_init_target} PROPERTY _is_qt_plugin_init_target TRUE)
     set_property(TARGET ${plugin_init_target} APPEND PROPERTY
diff --git a/cmake/QtPublicTargetHelpers.cmake b/cmake/QtPublicTargetHelpers.cmake
index d6465b4fb5..8471c45d05 100644
--- a/cmake/QtPublicTargetHelpers.cmake
+++ b/cmake/QtPublicTargetHelpers.cmake
@@ -299,3 +299,14 @@ function(__qt_internal_defer_promote_targets_in_dir_scope_to_global)
         endif()
     endif()
 endfunction()
+
+function(_qt_internal_set_up_static_runtime_library target)
+    if(QT_FEATURE_static_runtime)
+        if(MSVC)
+            set_property(TARGET ${target} PROPERTY
+                MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
+        elseif(MINGW)
+            target_link_options(${target} INTERFACE "LINKER:-static")
+        endif()
+    endif()
+endfunction()
diff --git a/cmake/QtTargetHelpers.cmake b/cmake/QtTargetHelpers.cmake
index 266bcac490..bc1d8f3620 100644
--- a/cmake/QtTargetHelpers.cmake
+++ b/cmake/QtTargetHelpers.cmake
@@ -188,14 +188,7 @@ function(qt_set_common_target_properties target)
             OBJCXX_VISIBILITY_PRESET hidden
             VISIBILITY_INLINES_HIDDEN 1)
     endif()
-    if(QT_FEATURE_static_runtime)
-        if(MSVC)
-            set_property(TARGET ${target} PROPERTY
-                MSVC_RUNTIME_LIBRARY "MultiThreaded$<$<CONFIG:Debug>:Debug>")
-        elseif(MINGW)
-            target_link_options(${target} INTERFACE "LINKER:-static")
-        endif()
-    endif()
+    _qt_internal_set_up_static_runtime_library("${target}")
     qt_internal_set_compile_pdb_names("${target}")
 endfunction()
 
diff --git a/src/corelib/Qt6CoreMacros.cmake b/src/corelib/Qt6CoreMacros.cmake
index 1dca7f887c..d812e21213 100644
--- a/src/corelib/Qt6CoreMacros.cmake
+++ b/src/corelib/Qt6CoreMacros.cmake
@@ -1587,6 +1587,7 @@ function(__qt_propagate_generated_resource target resource_name generated_source
         target_compile_definitions("${resource_target}" PRIVATE
             "$<TARGET_PROPERTY:${QT_CMAKE_EXPORT_NAMESPACE}::Core,INTERFACE_COMPILE_DEFINITIONS>"
         )
+        _qt_internal_set_up_static_runtime_library("${resource_target}")
 
         # Special handling is required for the Core library resources. The linking of the Core
         # library to the resources adds a circular dependency. This leads to the wrong