Created attachment 103583 [details]
backtrace of unreal engine effects demo with debug

(In reply to comment #31)
> (In reply to comment #30)
> > But every demo segfaults. Mostly in LLVMBuildBitCast().
> [...]
> > This is still a problem with register spilling that just looks different,
> > right?
> 
> No, that sounds like bug 81834.

So I built mesa with debug symbols and I guess debugging enables some
assertions because now fails at some assertion about Register.Index stuff. Full
backtrace attached.

(bug 81834 doesn't say what versions he uses. I use upstream llvm 214022 and
mesa git with the small patch I mentioned)

Of course it could be both problems at the same time.