[vax] Convert the backend to MODE_CC so it can be kept in future releases
This is a tracker bug for the convert the vax backend from CC0 to MODE_CC so it can be kept in future releases as there has been interest raised on the NetBSD/VAX mailing list:
See: http://mail-index.netbsd.org/port-vax/2020/04/16/msg003460.html
For the background of the CC0 transition, see:
> https://gcc.gnu.org/wiki/CC0Transition
I will be using this bug report to create a bounty on BountySource.com.
We have already successfully funded such a conversion for the m68k backend, see #91851. Another campaign is ongoing for the avr backend, see #92729.
To test the backend, the emulator SimH can be used to install the VAX port of NetBSD.
For that matter, a test image has been provided by John Klos:
> http://mail-index.netbsd.org/port-vax/2020/04/18/msg003481.html
There is also a generic howto which explains how to set up and install NetBSD/VAX inside SimH:
> http://www.netbsd.org/ports/vax/emulator-howto.html
SimH is available for immediate installation in openSUSE, Ubuntu, Debian and Fedora.
Alternatively, SimH can be obtained from the upstream project:
> https://github.com/simh
> http://simh.trailing-edge.com/