This does not occur with mesa 18.2.0 and llvm 6.
There is no interesting output from wine nor any mention in dmesg.
This still occurs with mesa-git and llvm-svn.
Graphics card is vega 56
Seems to definitely be a mesa issue and not llvm, built mesa 18.2.0 with latest llvm and the issue does not occur. Will attempt to bisect
Did you bisect?
tried to and the discovered this was an issue with using the lutris runtime, without it everything is fine