Comment # 6 on bug 94860 from lumks@ymail.com

(In reply to Michel Dänzer from comment #5)
> Setting the environment variable R600_DEBUG=nodcc for the kwin process works
> around this problem for me.

+1 
it also worksaround wayland session and maybe also this one:
https://bugs.kde.org/show_bug.cgi?id=361154 (i dont know right now for sure but
it looks like it does)