diff --git a/src/corelib/kernel/qcore_mac.mm b/src/corelib/kernel/qcore_mac.mm
index f0e4ecc6e2..a3d1669b81 100644
--- a/src/corelib/kernel/qcore_mac.mm
+++ b/src/corelib/kernel/qcore_mac.mm
@@ -526,7 +526,7 @@ void QMacKeyValueObserver::removeObserver() {
 KeyValueObserver *QMacKeyValueObserver::observer = [[KeyValueObserver alloc] init];
 
 QT_END_NAMESPACE
-@implementation KeyValueObserver
+@implementation QT_MANGLE_NAMESPACE(KeyValueObserver)
 - (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object
         change:(NSDictionary<NSKeyValueChangeKey, id> *)change context:(void *)context
 {
diff --git a/src/corelib/kernel/qeventdispatcher_cf.mm b/src/corelib/kernel/qeventdispatcher_cf.mm
index 0227778cee..2d2a7ee864 100644
--- a/src/corelib/kernel/qeventdispatcher_cf.mm
+++ b/src/corelib/kernel/qeventdispatcher_cf.mm
@@ -89,7 +89,7 @@ QT_USE_NAMESPACE
 
 QT_NAMESPACE_ALIAS_OBJC_CLASS(RunLoopModeTracker);
 
-@implementation RunLoopModeTracker {
+@implementation QT_MANGLE_NAMESPACE(RunLoopModeTracker) {
     QStack<CFStringRef> m_runLoopModes;
 }