MacPorts and 64-bit

[Rainer Müller]

Frederick Akalin wrote:
> I submitted a patch to provide a 64-bit variant of gmp a while ago: (
> http://trac.macosforge.org/projects/macports/ticket/15002 ) but it is
> kind of kludgy in that you have to specify the variant manually and
> that any program/package that uses the 64-bit version must also be
> compiled with -m64.

Please note it is +x86_64 and not +i386_64. As long as we can't check if 
a port was build with a specific set of variants, I don't think we can 
use this. Depending ports wouldn't know how to be built, or you also 
provide a patch for all them :-)

> This brings up the issue of how 64-bit issues should be handled in
> general, which has been brought up before, I believe.  Is there way to
> build 'universal' libraries?  Can someone give me some background on
> the 64-bit-related issues with MacPorts?  I can't promise a lot of
> time, but I'd be interested in helping.

With 1.6.0 you can already build universal binaries with i386 and ppc 
using the +universal variant.

In trunk you can also use +universal to build pure 64-bit binaries. It 
contains a new setting universal_archs in macports.conf where you can 
set which archs should be build by using +universal. If you set it to 
x86_64 (or ppc64) only, you get pure 64-bit binaries. Consider it some 
kind of hack, and please not that +universal does not work for all ports...

> Also, why is -m64 not the default on Apple's gcc?  Of course, I'm
> guessing it's for backwards-compatibility reasons, but will it
> eventually be the default?  I haven't had a (64-bit) mac until a few
> months ago so I haven't been keeping tabs on it.

I suppose the default of 32-bit will not change on Leopard anymore...

Rainer