[OpenCL] crash at import ...

[kif]

I stumbled on this bug when setting up an environment for debugging/profiling OpenCL code (Portable CL + Cuda JIT compilation to profile on nvidia GPU). The error message printed before the program abortion is:

Aborted

After inspection, it turns out it is the probing for atomic operation on devices in 'silx.opencl.atomic' which causes the crash.

Deeper inspection with gdb shows that PoCL explicitely asked for the termination of the program by calling pocl_cuda_abort_on_error. My problem is that we are compiling some code to actually validate if those atomic operation at available or not. Here, the PTX code is apparently not useable. silx expected an exception, not a brutal program termination !

What needs to be done:

• [x] Warn the developers of PyOpenCL (probably nothing they can do on their side) and PortableCL.
• [x] Deactivate the probing of devices when driver=="ProtableCL" and devicetype=="GPU" since it crashes the program without being able to recover it at the Python level.