diff --git a/vcl/osx/salinst.cxx b/vcl/osx/salinst.cxx
index 78755d1f1597..7936b4a99f00 100644
--- a/vcl/osx/salinst.cxx
+++ b/vcl/osx/salinst.cxx
@@ -445,7 +445,8 @@ bool AquaSalInstance::isNSAppThread() const
 
 void AquaSalInstance::handleAppDefinedEvent( NSEvent* pEvent )
 {
-    switch( [pEvent subtype] )
+    int nSubtype = [pEvent subtype];
+    switch( nSubtype )
     {
     case AppStartTimerEvent:
         AquaSalTimer::handleStartTimerEvent( pEvent );