Re: feature for C++ standards compliance

From: Andrey Semashev (andrey.semashev_at_[hidden])
Date: 2021-02-25 22:04:33

On 2/26/21 12:15 AM, Robert Ramey via Boost wrote:
> On 2/25/21 12:48 PM, Gavin Lambert via Boost wrote:
> 
>> Conditioning a boost test on boost version < N is equivalent to just 
>> unconditionally suppressing it, no?
> 
> No - because boost version <= 1.75 math library supports C++03 while 
> other versions don't/wont.

I think the point was that with the Boost version check you won't be 
running these tests *at all* in the current and future Boost.

>> Isn't the goal to only suppress it when not compiling >= C++11?
> yep
> 
>> Shouldn't you just check __cplusplus >= 201103 for that?
> 
> Hmmm - is this portable on all compilers?  Is this part of config.hpp?

__cplusplus is a standard C++ macro, but not all compilers consistently 
define it to >= 201103 in C++11 mode. Most notably, MSVC doesn't.

If you want to check macros (which is what I'm doing in Boost.Integer to 
solve a similar problem with Boost.Multiprecision) then I'd suggest to 
check Boost.Config macros for the particular C++11 features that are 
required by Boost.Math. You may even peek in Boost.Math sources to see 
what these macros are, if they are checked there.