mdspan
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kokkos
Build failing on GCC arm due to _N defined as a macro
ctype.h on that platform defines
#define _U 01
#define _L 02
#define _N 04
#define _S 010
#define _P 020
#define _C 040
#define _X 0100
#define _B 0200
which breaks mdspan in many places since some of those names are used as template parameters.
Names starting with an underscore and upper case letter are reserved by the standard to be used by an implementation so I think the proper way to handle this is rename the template parameters. I didn't find a quick way to automate the renaming otherwise I would have made a pull request.
Yeah this implementation is meant to go into the standard implementation hence we also use underscores, obviously we need to make it compatible with the ones we want to intregrate with. But seriously who injects single letter macros into the global namespace lol, almost as bad as MSVC definine MIN and MAX as macros ....
On the other side I don't think there is a reason we should put _ in front of tempalte parameters in the first place.
On the other side I don't think there is a reason we should put _ in front of tempalte parameters in the first place.
Right, I don't think it's our job necessarily to pre-mangle symbols. If a standard library implementation wants to adopt our reference mdspan implementation, they will do that mangling on their own.
This is a bit relevant to #185, though. We've been wanting to use a prefix _ as a way to mark macros as implementation details. On the other hand, "namespaced" macros like _MDSPAN_INLINE_FUNCTION probably won't collide with an existing standard library implementation's symbols.
Correct me if I'm wrong but I don't think the name of template parameters have to be mangled at all because they are no symbols and they don't leave the scope of the template definition. But - as we can see in this particular issue - they are affected by global macros. So consequently I would say they actually may not be mangled at all.
@LnnrtS wrote:
Correct me if I'm wrong but I don't think the name of template parameters have to be mangled at all because they are no symbols and they don't leave the scope of the template definition.
Just to clarify: The library in this repository does not need to mangle template parameters. Standard Library implementations of mdspan (which are coming) generally mangle symbols to avoid collisions with users' macros.
Ok I see. I wasn't taking user defined macros into account (I mean, why would anybody.. ;-))
We may wanna mangle but just use some larger names for the template parameters. That said I still think its insane to have in any library single letter macros, mangled or not.