ville@kepakko ~ $ blender
64 bits compiles will give incorrectly saved .blend files. Do not use it.
*** If you continue to run this executable, you really are quite stupid ***
guessing 'blender' == '/usr/bin/blender'
Compiled with Python version 2.4.
Checking for installed Python... got it!
blender: xcb_xlib.c:41: xcb_xlib_lock: Assertion `!c->xlib.lock' failed.
Steps to Reproduce:
1. emerge blender
3. witness the error
xcb is known to cause issues. Report upstream...
Keyworded media-gfx/blender-2.43 ~amd64.
Other versions of blender have also been keyworded due to security bugs.
Due to the fact that blender creates incorrect .blend files on amd64, we will not be marking it stable anytime soon. Removing firstname.lastname@example.org for that reason - feel free to readd us if you think you need to.
kepakko ~ # USE="-xcb" emerge -va libX11
"Fixes" it so blender at least runs. Good enough for the time being.
I've also run into this problem, while upgrading to libX11-1.1.1-r1 and enabling "xcb" USE flag. Just for curiosity. Before merging libX11-1.1.1-r1 xcb-proto-1.0 and libxcb-1.0 were installed.
In the mean time I noticed, that openoffice-2.1.0-r1 refuses to start, gives signal 6 and tries to coredump. The reason for this was turned out to share similarities with the above mentioned bug:
"soffice.bin: xcb_xlib.c:50: xcb_xlib_unlock: assertion `c->xlib.lock' failed."
It seems that other programs are also affected and other distributions also have problems related to this issue. Take a look at on this:
Removing "xcb" USE flag solves the problem. However it would be good to treat this bug in the correct way instead of this workaround before nastier symptoms could show up.
You're welcome to try the libxcb ebuild from:
Somewhat ugly, but best way I could see of solving the problem until clients are updated for the new xcb locking.
Please make sure you have all the latest (~arch) X libraries, particularly these:
Ensure that, then test again and report back with your results. Please reopen the bug when you reply.