RE: Exercise07, MacOSX and specifying work group size.

[cabreraam]

From a call to clGetDeviceInfo, I found that the max work-group size for my Intel Core i7 processor is 1024. This should definitely be able to complete the matrix multiply with the given parameters in the solution (64 work elements per work group). However, I get the following error:

Error code was "CL_INVALID_WORK_GROUP_SIZE" (-54)

Some quick googling led me to this link which states that the OpenCL implementation on Mac OS is "a little funky" and that "it is very hard to support CPUs on OSX".

I just changed the device index in the code to select something other than the CPU (on my machine, I have the integrated Intel Iris GPU as well as a dedicated GPU) and the example worked fine. Just a heads up for people who were banging their head against the keyboard like me!