Re: pkg/46308: pkg_add should not display warnings for known compatible platform mismatches

[Havard Eidnes <he%NetBSD.org@localhost>]

>  >  We have incomaptible minor versions?  That seems like a problem to me.
>  >
>  >  How about compatibility across tiny versions?
>
>  Well, 5.1 is the state of the netbsd-5 branch at some point between
>  5.0.0 and 5.1.0 release, right?

No.  There are no 5.0.0 or 5.1.0 releases.  Instead, we call these
releases along the netbsd-5 branch 5.0 and 5.1 respectively.  Kernels
built from the netbsd-5 branch between the releases of 5.0 and 5.1 is
designated 5.0_STABLE.

>  So it might have the new X libraries or might not have
>  them. Impossible to tell. x.y.z and x.y.z+1 are most likely
>  compatible, not sure if we ever pulled up a binary incompatible ABI
>  change. I'd still say it is backwards compatible only, e.g. new
>  functions may exist in z+1.

I vaguely remember us at one point bumping the major of a library
between minor releases.  So to use packages built on the older
version, you'd have to also have the library with the old major
present, e.g. via a compat package.

I don't think we've ever made a change which broke backward
compatibility in any more serious way(?)  At least that's clearly not
the intent.

So... Packages built for a lower-numbered release should at least be
usable on another release of the same major, and possibly also on
newer major releases.  So ... packages built on 5.0 should be usable
on both 5.0, 5.1 and 5.1.2 etc., and packages built on 5.0.2 should
also be usable on both 5.1 and 5.1.2, and chances are very good that
they'll be usable also on 5.0 as well, since we're only supposed to
fix serious security-related issues in tiny releases, something 5.0.2
is an instance of.

Of course, there will always be a few packages which are so tightly
coupled to the particular version of the OS it is built for, but those
are few and far between.

Regards,

- Håvard