Regressions getting more common

Hi,

I don't know about other non-x86 architectures, but over the past year 
I've been noticing more and more regressions being introduced, 
unnoticed, for ARM/AArch64. This is not good and causes a lot of pain if 
you have to keep tracking things manually, like we do now.

The buildbots worked great for this very purpose, but Sergio has moved 
on to other duties (thanks for all the work!) and can't maintain it 
anymore. The builders are still there though, sitting mostly idle.
We have a beefy ARM/AArch64 builder, which I can maintain for others to use.

We can do better than to declare things OK after a single round of tests 
under x86, which has been the trend unfortunately.

The subject of better CI has come up multiple times on IRC, with sad 
memories of the gerrit experiment's demise. Now we're left with review 
by e-mail and no broad testing.

I think we need to discuss better validation pre-commit and possible CI 
solutions for GDB. It is pretty easy to exercise x86, but it doesn't 
sound fair to other architectures to have to keep cleaning up after 
things that have only been validated on that architecture.

It would be great to establish a roadmap so we can get GDB's testing to 
today's standards, and maybe revisit the use of more modern patch review 
tools while at it.

What do you think?