https://bugs.freedesktop.org/show_bug.cgi?id=78366
--- Comment #1 from Michel Dänzer michel@daenzer.net --- (In reply to comment #1)
Sorting processes by ram usage (on eg: top) would show no culprits; the memory was being leaked kernelside. Not even restarting X would fix the problem: A reboot was always necessary.
That would be a kernel bug then. But it's hard to imagine how that could only be triggered without LLVM...
BTW, you can still enable LLVM via the environment variable R600_LLVM=1 or R600_DEBUG=llvm.