Thanks for the report.  Can you try to reproduce the bug with a distutils setup script to confirm the bug and get an error log?  You may have to apply the patch from #11599 to get a complete error message.  (Also, superuser rights are not required for build, so let’s remove that too.)

I only know the basics about C compilation, and I only know that Mac OS is a strange and peculiar system, but let’s try to work on this bug :)  The distutils.unixccompiler module already has code to work around things in various Mac OS versions, so if there is an easy way to detect “when it’s no longer possible to compile for PPC”, there is hope.