Now in the code base for example instead of using std::pair you use boost::math::pair which aliases to either thrust::pair or std::pair depending on context.
What exactly do you mean by "depending on context"? I see a define based on which either one is chosen.
Since CUDA can use a range of host compilers the context is a CUDA environment for the determination of thrust vs std containers.
First thing that comes to my mind is: ODR violation. How do you avoid this when using such defines in headers? What is the benefit of implicitly using the CUDA types? Can you really use either in place of the other without being aware of that?
Not only can you use the CUDA types in place of the std types you have to since the std:: types simply do not exist in the libcu++ standard library. This avoids the ODR issue as well. They are all designed to be drop in replacements it seems because the NVIDIA docs direct you to cppreference: https://nvidia.github.io/cccl/libcudacxx/standard_api/utility_library/tuple....
1) Would these utilities be useful to you? 2) If yes, do you think that Boost.Config is the right home for them?
I would definitely make that a separate library with proper documentation, motivation and examples. Yes that might be small, but so are other base-libraries in Boost. That would also be the place to answer the why, where and how it is
That's fair, and seems to be the consensus so far. Matt