[cairo] Render EXTEND_REPEAT bug is back...

[Behdad Esfahbod]

On Sun, 2008-01-27 at 14:34 -0500, Owen Taylor wrote:
> > > Are you sure it's really *the* old buggy repeat bug and not another  
> > > bug
> > > that the same work-around code works around?
> > 
> > I'm not -- the symptoms look identical, but I don't know if the  
> > underlying cause is the same.  The mozilla bug report got updated; it  
> > doesn't seem to be limited to the radeon driver, people using sis and  
> > i810 at least are seeing it.  Do we have a testcase for this?  I can't  
> > remember if it's in the testsuite since it's platform-specific, but it  
> > would be good to be able to reproduce it without firefox.  If we  
> > don't, I can put one together tomorrow.
> 
> The original bug report on the X server:
> 
>  https://bugs.freedesktop.org/show_bug.cgi?id=3566
> 
> The patch attachment is no longer available (all
> bugzilla.freedesktop.org attachments got scrambled some years ago), but
> as you can see from the description, that bug had to do with a very
> specific logic error in the core RENDER framebuffer code. I haven't
> looked at the current version of that file, but it seems improbable to
> me that that particular logic error was reintroduced.

That patch is here:
http://gitweb.freedesktop.org/?p=xorg/xserver.git;a=commitdiff;h=7c84189ea1dc236bc979bb4bf158ecb1a6b45137;hp=2acd29c93fd3b3d438887f0ca9be6713db81c1e8

The bug doesn't exist in pixman these days as it's been switched over to
bit_image_t type that doesn't have x/y.  It's probably in the xserver
code calling pixman now.

> So, I think the first step here is to track down and figure out what the
> current X server bug you are seeing is, and what exactly is the scope of
> it. Before that, trying to figure out how to work around it seems like a
> risky and uncertain proposition.

Right.

> - Owen

-- 
behdad
http://behdad.org/

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