64bit variant naming scheme

[Ryan Schmidt]

On Dec 11, 2008, at 08:18, Takeshi Enomoto wrote:

> I think scientific users want not universal (i386 and ppc) but 64- 
> bit  (x86_64 and ppc64)
> if they have a 64-bit machine.

In MacPorts 1.6.0, "universal" means "i386 ppc" but in MacPorts 1.7.0  
and up, it only means "build for multiple architectures". That's what  
the description next to "universal" says when you type "port  
variants". Which architectures those are is up to the user; it can be  
configured in macports.conf by changing the universal_archs variable  
-- be that "i386 ppc" (the default) or "i386 ppc x86_64 ppc64" or  
"x86_64 ppc64" or "i386 x86_64" or whatever other combination.


> If a package is build for all the four (i386 x86_64 ppc ppc64),
> there will be not problem but it is not always easy to support this.
>
> For example source in fortran is problematic.
> gfortran in gcc43 -m64 option but not -arch x86_64 or ppc64.
> To build universal one needs to go through build process twice with  
> -m32 and -m64
> and use lipo later.
> I have not yet able to provide g95 64-bit.
>
> My point is building for two types of cpus and for 32/64 bit are  
> not always the same
> and an average scientific user wants 64 bit version for the host  
> (her/his local) machine.
>
> A universal Portfile has been posted for fftw-3, which is under  
> examination.
> <https://trac.macports.org/ticket/13814>
> It would be nice if port command itself have a similar function.
>
> Otherwise it would be nice to enable the user to choose 32/64 bit.

The user can choose -- by changing universal_archs in macports.conf.