documenting fix for clang error: reference to host function from device

[dokipen3d]

Here is what happens if you use clang 10 (see my other issues for how to get that working)....

coriander/soft/llvm-10.0.0/lib/clang/10.0.0/include/cuda_wrappers/new:57:7: error: reference to
      __host__ function 'free' in __device__ function
    ::free(ptr);
      ^

The fix seems to be to

1. update the __clang_cuda_runtime_wrapper.h file with the extern C definitions for new and delete which reference ::malloc and ::free. then...
2. include fake_funcs.h in cocl ABOVE the header which pulls in clangs new cuda wrapper prematurely.

Hopefully soon I'll get round to doing some PRs for these to get us all to be able to use clang 10. I'll make a separate issue for clang 11 as that requires some updates cocl as there are some clang API breakages.

[vidalperezbohoyo]

Sorry im noob. I dont know how to do that. Please can you explain step by step how to that? Thanks
I have clang 8 i think