diff --git a/src/plugins/platforms/cocoa/qcocoascreen.mm b/src/plugins/platforms/cocoa/qcocoascreen.mm
index 77de7511021..61f74761590 100644
--- a/src/plugins/platforms/cocoa/qcocoascreen.mm
+++ b/src/plugins/platforms/cocoa/qcocoascreen.mm
@@ -710,8 +710,8 @@ bool QCocoaScreen::isOnline() const
     // returning -1 to signal that the displayId is invalid. Some functions
     // will also assert or even crash in this case, so it's important that
     // we double check if a display is online before calling other functions.
-    auto isOnline = CGDisplayIsOnline(m_displayId);
-    static const uint32_t kCGDisplayIsDisconnected = int32_t(-1);
+    int isOnline = CGDisplayIsOnline(m_displayId);
+    static const int kCGDisplayIsDisconnected = 0xffffffff;
     return isOnline != kCGDisplayIsDisconnected && isOnline;
 }