Doesn't work for me either with llvm 216281 and mesa git

Oh and maybe it's not known, at least it wasn't so clear to me: I earlier wrote
how my GPU wouldn't get as warm as I expected nor did it display the expected
hashrate. This seems to be entirely controlled by the --intensity parameter. An
intensity of 10 or 11 seems to work okay to not get too many H/W errors and
higher results.

But I let it run for about an hour and bfgminer didn't seem to create a single
usable result again.
Runtime: 0 hrs : 52 mins : 51 secs
Average hashrate: 0.1 Megahash/s
Solved blocks: 0
Best share difficulty: 0
Share submissions: 0
Accepted shares: 0
Rejected shares: 0 + 0 stale (-nan%)
Accepted difficulty shares: 0
Rejected difficulty shares: 0
Hardware errors: 77

(The problem is pretty surely not bfgminer. I replaced CL_DEVICE_TYPE_GPU with
CL_DEVICE_TYPE_CPU and ran it via the intel opencl runtime on my CPU and there
I get accepted shares after very few minutes)