From 51886d7c9729f38344ad33490cc22be28bd9696b Mon Sep 17 00:00:00 2001
From: Laszlo Agocs <laszlo.agocs@qt.io>
Date: Tue, 6 Feb 2024 10:16:27 +0100
Subject: [PATCH] rhi: d3d11: Flush() when destroying a swapchain
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Task-number: QTBUG-120276
Change-Id: Iaf79c4dcf60d9a52bd562fd94976402cf570147d
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
(cherry picked from commit cff5a49cc20c3c9d98a5f97cd702a378ae29611b)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
(cherry picked from commit eb3529ea3554642c65402b89e39416bf657170d8)
(cherry picked from commit 87d075f7be7abdf56e622f2b5b20cdb6f6e418de)
---
 src/gui/rhi/qrhid3d11.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/gui/rhi/qrhid3d11.cpp b/src/gui/rhi/qrhid3d11.cpp
index 20ceeaf254a..ddd843667a3 100644
--- a/src/gui/rhi/qrhid3d11.cpp
+++ b/src/gui/rhi/qrhid3d11.cpp
@@ -4736,8 +4736,12 @@ void QD3D11SwapChain::destroy()
     }
 
     QRHI_RES_RHI(QRhiD3D11);
-    if (rhiD)
+    if (rhiD) {
         rhiD->unregisterResource(this);
+        // See Deferred Destruction Issues with Flip Presentation Swap Chains in
+        // https://learn.microsoft.com/en-us/windows/win32/api/d3d11/nf-d3d11-id3d11devicecontext-flush
+        rhiD->context->Flush();
+    }
 }
 
 QRhiCommandBuffer *QD3D11SwapChain::currentFrameCommandBuffer()