Aha, so Intel is Windows-only, that's a pity... But the tip about libOpenCL.so was good, turns out that the Nvidia-version was being used, and only reported its own platform, while the AMD-version detects both.
It does crash when it is about to look for devices in the ATI-platform, but I guess that must be something else then. At least now I believe that it will work in the end...
Number of platforms: 2
Platform Profile: FULL_PROFILE
Platform Version: OpenCL 1.0 CUDA 3.2.1
Platform Name: NVIDIA CUDA
Platform Vendor: NVIDIA Corporation
Platform Extensions: cl_khr_byte_addressable_store cl_khr_icd cl_khr_gl_sharing cl_nv_compiler_options cl_nv_device_attribute_query cl_nv_pragma_unroll
Platform Profile: FULL_PROFILE
Platform Version: OpenCL 1.1 ATI-Stream-v2.3 (451)
Platform Name: ATI Stream
Platform Vendor: Advanced Micro Devices, Inc.
Platform Extensions: cl_khr_icd cl_amd_event_callback cl_amd_offline_devices
Platform Name: NVIDIA CUDA
Number of devices: 1
Device Type: CL_DEVICE_TYPE_GPU
Device ID: 4318
Max compute units: 12
Max work items dimensions: 3
Max work items[0]: 512
Max work items[1]: 512
Max work items[2]: 64
Max work group size: 512
Preferred vector width char: 1
Preferred vector width short: 1
Preferred vector width int: 1
Preferred vector width long: 1
Preferred vector width float: 1
Preferred vector width double: 0
ERROR: clgetDeviceInfo(-30)
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