QWindow: use std::exchange when ... exchanging values

Replaces a three-liner with a more elegant, idiomatic one-liner.

Pick-to: 6.3
Change-Id: I57fbe5d808dffa44f6fceffb97c47f0c84ccd3df
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

1 files changed, 1 insertions, 3 deletions

diff --git a/src/gui/kernel/qwindow.cpp b/src/gui/kernel/qwindow.cpp
index 589304ccfc..030628b5db 100644
--- a/src/gui/kernel/qwindow.cpp
+++ b/src/gui/kernel/qwindow.cpp
@@ -2002,9 +2002,7 @@ void QWindowPrivate::destroy()
     // Unset platformWindow before deleting, so that the destructor of the
     // platform window does not recurse back into the platform window via
     // this window during destruction (e.g. as a result of platform events).
-    QPlatformWindow *pw = platformWindow;
-    platformWindow = nullptr;
-    delete pw;
+    delete std::exchange(platformWindow, nullptr);
 
     if (QGuiApplicationPrivate::focus_window == q)
         QGuiApplicationPrivate::focus_window = q->parent();