Compiler variants in portfile

[Sébastien Maret]

Le 17 avr. 2014 à 19:16, Sean Farley <sean at macports.org> a écrit :

> Sébastien Maret <sebastien.maret at icloud.com> writes:
> 
>> Le 17 avr. 2014 à 18:13, Sean Farley <sean at macports.org> a écrit :
>> 
>>> Sébastien Maret <sebastien.maret at icloud.com> writes:
>>> 
>>>> Le 17 avr. 2014 à 01:19, Sean Farley <sean at macports.org> a écrit :
>>>> 
>>>>> Sébastien Maret <sebastien.maret at icloud.com> writes:
>>>>> 
>>>>>> Le 27 mars 2014 à 22:03, Ryan Schmidt <ryandesign at macports.org> a écrit :
>>>>>> 
>>>>>>> On Mar 27, 2014, at 09:14, Sébastien Maret wrote:
>>>>>>> 
>>>>>>>> I’m writing a portfile for a software written in C/C++ and Fortran77/90:
>>>>>>>> http://trac.macports.org/ticket/42886
>>>>>>>> 
>>>>>>>> Following a comment macsforever2000, I’ve modified my original port to provide several fortran compiler variants. However, my port requires that CC, CXX, CPP, and FC/F77 are all from a gcc variant. For example, it's not possible to compile it using CC=clang and FC=gfortran-mp-4.8. How can I modify it so that all compilers come from the same compiler suite?
>>>>>>>> 
>>>>>>>> Thanks in advance for your advices.
>>>>>>> 
>>>>>>> You do know that as of Mavericks, trying to compile C++ code with anything other than clang is a fool’s errand, right?
>>>>>>> 
>>>>>>> https://trac.macports.org/wiki/FAQ#libcpp
>>>>>> 
>>>>>> No, I didn’t know that.
>>>>>> 
>>>>>>> *Why* is it not possible to compile your software using CC=clang and FC=gfortran-mp-4.8?
>>>>>> 
>>>>>> I tried that but the compilation failed. I don’t exactly why but I’ll have a closer look. 
>>>>> 
>>>>> Sorry for the late reply, but it took me a while to catch up. Ryan is
>>>>> right, of course. You should really figure out why they aren't compiling
>>>>> and try to fix those errors.
>>>> 
>>>> Thanks for your answer.
>>>> 
>>>> I found the problem: the link was done against libstdc++ instead if libc++. I’ve fixed this and I’ve just posted a revised version of the port on the tracker.
>>> 
>>> Looking at the portfile, things seem mostly fine. A few comments (which
>>> will hopefully help start documenting the compilers portgroup :-)
>>> 
>>> - compilers.choose is really meant to serve as a way to isolate a c-only
>>> or fortran-only build; since you specify both, you don't need it
>> 
>> But isn’t this needed to set both CC, FC and CPP ? 
> 
> No, if you leave compilers.choose blank, then it will set all the compilers.
> 
>>> - removing the clang variants only stops macport's clang compilers from
>>> being used; this is fine but since you don't need c++ you could mix
>>> clang with gfortran
>> 
>> Indeed I do need C++. And since a Fortran compiler is also needed, I would prefer to compiling Fortran and C with compilers from the same compiler suite (GCC) to avoid link problems. In addition the package requires CPP from GCC to compile properly (it is used in a non-standard way to pre-process Fortran code, and this does not work with Apple’s CPP).
> 
> If you need C++, then you forgot to mention it in compilers.choose
> (missing 'cxx’).

If i put cxx in compilers.choose (or leave compilers.choose blank) and install the +gcc48 variant the package, it uses g++-mp-4.8 to compile the C++ part of the code. This is not what I want. I need the C++ code to be compiled with clang++ (as advised by Ryan), and the rest with GCC4.8. Setting compilers.choose to  "cc cpp fc » does this.

By the way: this compiling C++ with anything other than clang is not recommended, shouldn’t compilers 1.0 enforce that rule and set compiler.cxx to clang++ by default?

> Also, "non-standard way to pre-process Fortran code"
> ... I didn't realize Fortran had a standard ;-P
> 
>> In fact I removed the clang variants because clang does not compile Fortran (same for drgaonegg). Why are variants present when require_fortran is set ? 
> 
> But dragonegg does compiler Fortran? That's mostly why it existed.

I didn’t know that. Yet clang does not compile Fortran, and it shows up in the variants even when require_fortran is set. But I guess it is the port file developer responsibility to blacklist compiler than can’t compile his port.

>>> - what is it with IRAM, Labri, and Enseeiht not using autoconf? is
>>> everyone in France allergic to autotools?
>> 
>> I’m not...  In fact, I would love them to use autotools. It would make the packaging a lot easier. I’ll forward your comment to them :-)
> 
> MUMPS and SCOTCH code development can only be measured on geological
> timescales.