[Python-Dev] Drop OS/2 and VMS support?

["Martin v. Löwis"]

> Ok, I added OS/2 and VMS to the PEP 11. I also opened any issue to
> remember that I should do something to raise an error on build.

For OS/2, I propose to syntactically break the makefile; anybody trying
to build it should then run into that, and
a) can easily overcome the limitation (probably to then run into more
   severe problems), and
b) consider taking over maintenance if they are interested

For VMS, I *think* the build process is configure-based (but I may
misremember); if so, adding an exit into configure.in would be
appropriate. Else an #error in a central header file may do as well.

Or perhaps we could always use the #error if we can trust that compilers
will honor it.

Regards,
Martin