Originally Posted by lemmens
FYI : I also installed Debian Wheezy on the same KVM/Qemu virtual machine. Debian Wheezy has the same QT and KDE major version numbers and there I don't see any problems with kwin. As this is the same hardware I don't expect it to be a a (virtual) hardware issue. Only possiblility could be that the compiler options used on Slack and Debian may have been slightly different ?
Tomac: In the thread you mention it seems that Qt was fixed : it may be a good idea to include this updated minor release of QT in Slackware 14.0 final ?
From the Debian thread, and from the changelog of qt4-x11 source package, it looks like they decided to remove Fix-JIT-crash-on-x86-64-avoid-32-bit-branch-offset-o patch from the Debian package:
So actually, it wasn't the matter of an update to QT library, but of removing a patch that was previously applied to it.
I think this could be the reason why it works on Debian Wheezy - however, I don't know if the QT4 packages with this patch ever reached Wheezy or if they stayed in Debian Sid only.
I compared patches used to fix JIT issue in Debian and Slackware. I found them under the following locations:
Slackware patch: ftp://ftp.slackware.pl/pub/slackware....crash.diff.gz
Debian patch: http://anonscm.debian.org/gitweb/?p=...1fef79566caf64
- can be found through the history of qt4-x11 package at: http://anonscm.debian.org/gitweb/?p=....git;a=summary
Both patches contain changes made to the same set of source files - however, the order of files is different in them, making it bit difficult to compare them. After sorting files in both patches (sorted versions in attachment) and comparing their contents, it looks like they are essentially the same - the Debian one seems to contain some hints at "@@" lines (not sure what they exactly are). So, in my opinion, the problems that Debian folks encountered were caused by essentially the same patch as the one used in Slackware. After removing the patch from Debian package, issues didn't occur anymore for them.
On the other hand, the patch itself fixes some other issues, so probably making decision whether this patch should stay or not won't be an easy one :|