clang 3.4 can't be configured (part of a selfupdate)

[Ryan Schmidt]

On Aug 1, 2016, at 3:07 AM, Jeremy Huddleston Sequoia wrote:
> 
> On Jul 31, 2016, at 23:49, Ryan Schmidt wrote:
>> 
>> ld: warning: ignoring file /usr/lib/libc++.dylib, file was built for unsupported file format ( 0xcf 0xfa 0xed 0xfe 0x 7 0x 0 0x 0 0x 1 0x 3 0x 0 0x 0 0x 0 0x 6 0x 0 0x 0 0x 0 ) which is not the architecture being linked (i386): /usr/lib/libc++.dylib
>> 
>> libcxx needs to be installed with the universal variant prior to this step. I still think it would be a good idea if we made the libcxx port install with the universal variant automatically since not having it installed universal will cause problems like these. 
> 
> Oh... because i386 is default on SL and cmake is likely not including -arch x86_64 ... ?
> 
> That sounds like a cmake bug, but we should figure out a good workaround.

No no, the cmake portgroup (which libomp uses) sets architectures correctly, and x86_64 is the default on Snow Leopard and later. But if you want to install a C++-using port universal, libcxx will need to be universal, and MacPorts won't ensure that because libcxx isn't listed as a dependency of every C++-using port. And libomp is being built universal because its universal variant defaults to on, which was done because of https://trac.macports.org/ticket/50511


> libcxx depends on libcxxabi which depends on libunwind and libmacho.  We'd need to force all four to build +universal for that.
> 
> r150880

Oh of course, I didn't see the dependencies because I was looking at the port on a newer OS. Thanks, this should help.