On solaris, if you build a 64 bit python and use it to build an extension, it will not properly link the module.

Apparently solaris requires the -m64 flag in the linker as well as the compile steps.  Python distutils successfully compiles all the object files using -m64, but it fails to link with -m64 causing the entire build to fail if the extension needs a 64 bit library dependency ( will get 'incompatible library' errors from the linker ).

To reproduce:
build python with CFLAGS="-m64 -O3" LDFLAGS="-m64"
build a C extension that depends on a 64 bit library (python setup.py install)

I assume that it would work if the C extension does not need a specific 64 bit library as the linker will not go and look for the wrong version of file.  So its a very uncommon but annoying bug.

> ld --version
GNU ld (GNU Binutils) 2.20.1.20100303
Copyright 2009 Free Software Foundation, Inc.
This program is free software; you may redistribute it under the terms of
the GNU General Public License version 3 or (at your option) a later version.
This program has absolutely no warranty.