On May 5, 2018, at 19:36, Craig Treleaven wrote:
> A couple of times recently, I’ve noticed boilerplate in ports that require
> C++14. After including the compiler_blacklist_versions portgroup, they then
> do some gymnastics like:
>
> compiler.blacklist *gcc-3.* *gcc-4.* {*gcc-5.[0-3]} \
> {clang < 800} macports-clang-3.4
> macports-clang-3.5 macports-clang-3.6 macports-clang-3.7
>
> Would it not be easier to use and maintain if we had some shorthand
> definitions. Maybe something like:
>
> compiler.blacklist ${min_cxx14}
>
> “min_cxx14” would be defined in the portgroup and then expand to the
> above...assuming the above actually does a good job of blacklisting compilers
> that don’t support C++14!
>
> A major advantage is that if our list of non-C++14 compilers ever changes, it
> only needs to be updated in one spot.
>
> I suspect there would be a few other shorthand lists that could be
> pre-defined.
>
> Thoughts?
Yes, we should have support for specifying the required language standard(s) in
Portfile, so that MacPorts could then select a compatible compiler.
Until we have that, you need to blacklist incompatible compilers.
If you require C++11, include the cxx11 1.1 portgroup which will do what's
needed for you, including blacklisting incompatible compilers and ensuring the
right C++ standard library is used.
If you require C++14, include the cxx11 1.1 portgroup and additionally use
"compiler.blacklist-append {clang < 602}".
I'm not familiar with the capabilities or functionality of the languages 1.0
portgroup.
