evince crashes the X server

[Dave Howorth]

On Thu, 10 Jul 2025 09:33:12 -0400 (EDT), Vladimir Dergachev wrote:

> On Thu, 10 Jul 2025, Eyal Lebedinsky wrote:
> 
> > On 10/7/25 14:57, Vladimir Dergachev wrote:  
> >> 
> >> Odd error. I don't see any hits on Google for 
> >> imprecise_trapezoid_span_converter
> >> 
> >> Can you try running
> >> 
> >> find /usr/ -type f -print0 | xargs -0 grep -H 
> >> imprecise_trapezoid_span_converter  
> >
> > grep: /usr/lib64/xorg/modules/drivers/intel_drv.so: binary file
> > matches
> >
> > $ ls -l /usr/lib64/xorg/modules/drivers/intel_drv.so
> > -rwxr-xr-x 1 root root 2157928 Jan 19 11:00 
> > /usr/lib64/xorg/modules/drivers/intel_drv.so
> >
> > $ dnf provides /usr/lib64/xorg/modules/drivers/intel_drv.so
> > xorg-x11-drv-intel-2.99.917^20240506gitce811e7-63.fc42.x86_64 :
> > Xorg X11 Intel video driver
> > Repo         : @System
> > Matched From :
> > Filename     : /usr/lib64/xorg/modules/drivers/intel_drv.so
> >
> > xorg-x11-drv-intel-2.99.917^20240506gitce811e7-63.fc42.x86_64 :
> > Xorg X11 Intel video driver
> > Repo         : fedora
> > Matched From :
> > Filename     : /usr/lib64/xorg/modules/drivers/intel_drv.so
> >  
> 
> Interesting!
> 
> This suggests your intel driver is rather new and has this bug, as on
> my systems (Kubuntu LTS) intel_drv.so does not have references to 
> imprecise_trapezoid_span_converter. In fact it is so bleeding edge
> that Google does not show hits to repository with
> "imprecise_trapezoid_span_converter".
> 
> Looks like intel driver contains two bugs: whatever triggers the 
> assertion, and assertion that when violated exits X-server. It is
> likely a drawing code, so it could just draw nothing.
> 
> I would suggest first to check RedHat changelogs to see where the
> code came from and whether they backported any patches. It could be
> the error occurred during porting. If this is not the case, then
> contact intel_drv developers, which I think is Intel - they should
> have forums to post a question to.
> 
> best
> 
> Vladimir Dergachev

See
https://gitlab.freedesktop.org/xorg/driver/xf86-video-intel/-/blob/master/src/sna/sna_trapezoids_imprecise.c

for a/the definition of the function. It hasn't been changed in ten
years though, so something else must be causing a problem, I think.