Bug#841951: [PATCH]: bitcoin-qt segfaults on startup

[Erik de Castro Lopo <erikd@mega-nerd.com>]

Hi,

The attached patch applied to the qtbase-opensource-src-5.7.1+dfsg
source packages fixes the segfault for me.

The 5.8.0 package in experimental without this patch still segfaults.
I haven't tried applying this patch to that version.

Cheers,
Erik
-- 
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Erik de Castro Lopo
http://www.mega-nerd.com/

Description: qglxconvenience: Avoid NULL dereference

Index: qtbase-opensource-src-5.7.1+dfsg/src/platformsupport/glxconvenience/qglxconvenience.cpp
===================================================================
--- qtbase-opensource-src-5.7.1+dfsg.orig/src/platformsupport/glxconvenience/qglxconvenience.cpp
+++ qtbase-opensource-src-5.7.1+dfsg/src/platformsupport/glxconvenience/qglxconvenience.cpp
@@ -207,6 +207,9 @@ GLXFBConfig qglx_findConfig(Display *dis
 
             QXlibPointer<XVisualInfo> visual(glXGetVisualFromFBConfig(display, candidate);
 
+            if (! visual)
+                continue;
+
             const int actualRed = qPopulationCount(visual->red_mask);
             const int actualGreen = qPopulationCount(visual->green_mask);
             const int actualBlue = qPopulationCount(visual->blue_mask);