<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_NEW " title="NEW - record-paint-alpha-clip-mask.xcb.rgb24 random failure" href="https://bugs.freedesktop.org/show_bug.cgi?id=84330#c3">Comment # 3</a> on <a class="bz_bug_link bz_status_NEW " title="NEW - record-paint-alpha-clip-mask.xcb.rgb24 random failure" href="https://bugs.freedesktop.org/show_bug.cgi?id=84330">bug 84330</a> from <a class="email" href="mailto:psychon@znc.in" title="Uli Schlachter <psychon@znc.in>"> Uli Schlachter</a> <pre>Sorry that I missed this report for two years. No idea how that happened. Also: sorry, but I think that this might be a bug in the X11 server. _composite_traps() is a wrapper around _cairo_xcb_connection_render_trapezoids() that converts from "cairo" to "X11", so this doesn't do anything special here. So, we are sending a Trapezoids-request with an empty list of traps. Looking at the render spec, a Trapezoids-request with an empty list of traps should just copy the source to the target. I bet some code is incorrectly optimizing this away, assuming it is a no-op (which it would e.g. be for operator OVER or ADD). And indeed, the bug is easy to find: <a href="https://cgit.freedesktop.org/xorg/xserver/tree/render/render.c?id=e8e36755abb17872d669b88d33ca9adc511029a0#n745">https://cgit.freedesktop.org/xorg/xserver/tree/render/render.c?id=e8e36755abb17872d669b88d33ca9adc511029a0#n745</a> Does anyone have the time to test if this bug is fixed if the above "if (ntraps)" is just removed? (Afterwards, I guess we should still work around this in cairo, but at least we will also get the Xorg bug fixed and we can have a comment saying why this is needed.)</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> </ul> </body> </html>