Commit efebee5ab854c78e39d17da2f7e5f521ec9c1fef
2011-07-06T16:47:29
Fix the case where there are no GPUs, and exit if they give errors. If there are no GPUs, set nDevs to 0 not -1 (status is set to an unhelpful -1001 here on my laptop, so we can't rely on a particular status value). Also, if nDevs is -1, exit rather than screwing up later.