On Sep 17, 2010, at 3:22 PM, Ryan Schmidt wrote:
> AFAIK the differences do still exist and will always exist. The problem as I
> understand it is if you try to compile library A with compiler X and compile
> program B (which links with library A) with compiler Y, inexplicable problems
> can surface, which is why all the science ports are supposed to be
> standardized to use a single compiler. (All of MacPorts, really, uses a
> single compiler -- Apple's, but with the science ports, they often need to
> use fortran, which means non-Apple GCC, and if one port is doing that, then
> its dependencies should have the option to use that same compiler too.)
Ah; yes. What you're referring to is the case that:
+ library A required libgfortran (or libgcc)
+ library B required library A -and- libgfortran (or libgcc) as 1st order link
libraries (meaning that symbols would end up undefined without linking to both
of those libraries)
... we definitely want to make sure that the libgfortran (or libgcc) is the
same, otherwise the end results are undefined (competing libraries containing
roughly the same ABI).
I think the issues do not arise with numpy, since it does not -directly- rely
on libgfortran (or any of the other gcc4X series libraries). If I do:
% otool -L
/opt/local/Library/Frameworks/Python.framework/Versions/2.6/lib/python2.6/site-packages/numpy/linalg/lapack_lite.so
/opt/local/lib/liblapack.dylib (compatibility version 0.0.0, current
version 0.0.0)
/opt/local/lib/libptf77blas.dylib (compatibility version 0.0.0, current
version 0.0.0)
/opt/local/lib/libptcblas.dylib (compatibility version 0.0.0, current
version 0.0.0)
/opt/local/lib/libatlas.dylib (compatibility version 0.0.0, current
version 0.0.0)
/usr/lib/libSystem.B.dylib (compatibility version 1.0.0, current
version 125.2.0)
and, that's the only .so module that asks for fortran linking. So, while I
agree in general on the use of the same gcc4X options, I think in this case an
exception can be made. - MLD
_______________________________________________
macports-dev mailing list
[email protected]
http://lists.macosforge.org/mailman/listinfo.cgi/macports-dev
