Add prefixes to macros in in config.hpp.in

[al42and]

Summary

To prevent potential macro naming conflicts between oneMKL and client applications, this RFC proposes adding a unique prefix (such as ONEMKL_ or ONEAPI_ONEMKL_) to all macros defined in oneMKL's public API.

Problem statement

oneMKL defines a bunch of configuration macros in config.hpp, which is transitively included in the <oneapi/mkl.hpp> file.

Those are ENABLE_<backend>_BACKEND for each enabled backend, BUILD_SHARED_LIBS and REF_(BLAS|CBLAS)_LIBNAME.

As a consequence, the client application that tries to use oneMKL will also have them all defined. This could be useful, but, since macros don't obey any scope rules, they can also easily cause confusion if the client application itself uses, e.g., ENABLE_CUFFT_BACKEND or BUILD_SHARED_LIBS.

ES.33 in C++ Core Guidelines recommends adding supposedly unique prefixes (e.g., your organization’s name) to the macro names.

As such, I suggest adding ONEMKL_ or ONEAPI_ONEMKL_ prefix to all the macros defined in the public API.

Details

• Those macros are not part of the specification as far as I can tell, but they can (intentionally or not) affect user applications.

[Rbiessy]

Thanks for the RFC, I agree this would be nicer. I would suggest using ONEAPI_ONEMKL_ for now. Is this blocking you? We may have the bandwidth to work on this but contributions are welcome if anyone needs this soon.

[al42and]

Is this blocking you?

Not blocking, just wanted to raise a concern since it's part of public API (I don't have a link at hand, but it was suggested in one of the examples to check these variables).

We may have the bandwidth to work on this but contributions are welcome if anyone needs this soon.

Ok! 😉