From a69a0e8254b79c62fad7372e8c14f66d440ad744 Mon Sep 17 00:00:00 2001
From: Laszlo Agocs <laszlo.agocs@qt.io>
Date: Tue, 23 Jan 2018 10:21:49 +0100
Subject: [PATCH 50/74] glx: Avoid losing the stereo flag in QSurfaceFormat

Task-number: QTBUG-59636
Change-Id: I38394009993e92ab9db853a1450687fc48e471f5
Reviewed-by: Andy Nichols <andy.nichols@qt.io>
---
 src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.cpp b/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.cpp
index e2e573f0e1..fc1806f982 100644
--- a/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.cpp
+++ b/src/plugins/platforms/xcb/gl_integrations/xcb_glx/qglxintegration.cpp
@@ -134,7 +134,11 @@ static void updateFormatFromContext(QSurfaceFormat &format)
     }
 
     format.setProfile(QSurfaceFormat::NoProfile);
+    const bool isStereo = format.testOption(QSurfaceFormat::StereoBuffers);
     format.setOptions(QSurfaceFormat::FormatOptions());
+    // Restore flags that come from the VisualInfo/FBConfig.
+    if (isStereo)
+        format.setOption(QSurfaceFormat::StereoBuffers);
 
     if (format.renderableType() == QSurfaceFormat::OpenGL) {
         if (format.version() < qMakePair(3, 0)) {
-- 
2.14.3