Re: RFC: Changing GDB's version numbering scheme

[Andrew Burgess <andrew dot burgess at embecosm dot com>]

* Joel Brobecker <brobecker@adacore.com> [2018-10-31 10:25:13 -0700]:

> Hello again,
> 
> Quick summary of the discussion so far: The only feedback this
> discussion drew was negative feedback. If you would like to support
> this proposal, you should speak up; otherwise, I'm inclined to
> let the matter drop.

I would support changing the numbering scheme.

The problem I see with the current scheme is that I don't understand
what the criteria is for bumping the major version number.  Maybe it's
one of those things that you'll just know it when you see it.

For me the concern that the new scheme could cause confusion is not a
big one, under both the old and new scheme version 10.1 is "better"
than 9.1, and 9.2 is "better" than 9.1.  The only difference is that
under the new scheme 9.2 is more closely related to 9.1 than it used
to be.  Most users I suspect only care about finding the "best"
release currently available.

In the rare case that someone feels that they really can't move onto a
new GDB branch for *reasons*, then they might not move from 9.1 to 9.2
because that used to mean a new branch.  This is easy enough to solve
by just rewording the website to make it clear that 9.2 is the next
release for the v9 branch.

Thanks,
Andrew


> 
> > During this year's GNU Cauldron, we discussed the version numbering
> > scheme the GDB project has been following so far, because a number
> > of users were confused by it.
> > 
> > At the moment, as you know, GDB's version number is composed of at
> > least 2 numbers (MAJOR.MINOR) with an optional micro version suffix
> > (MAJOR.MINOR.MICRO). During each release cycle, we usually increase
> > the minor number. For instance, since the last release branch was
> > an 8.2 branch, the next GDB release branch is currently expected to
> > be 8.3.
> > 
> > The problem with that numbering is that a number of users got confused
> > by that numbering, thinking that all releases made with the same MAJOR
> > number were made from the same release branch. So, they thought for
> > instance that 8.0, 8.1 and 8.2 were made from the same branch.
> > 
> > The proposal, to avoid this issue, is to change the version numbering
> > scheme to increment the major version for each release branch. We did
> > not go into too much detail during the discussion, but generally
> > speaking, so part of the proposal below is me extrapolating in terms
> > of some of the details while thinking things through a little more --
> > please feel free to comment and provide other suggestions.
> > 
> > Let's assume that the last release we made had a major version number
> > of <N> (in our case, <N> is 8):
> > 
> >   (a) The next branch would be gdb-<N+1>-branch
> > 
> >   (b) Once the branch is cut, we increment the version number on
> >       master to be <N+1>.50.DATE
> > 
> >   (b) The first pre-release would be numbered "GDB <N+1>.0.90" [2].
> >       For instance, our next pre-release would be "GDB 9.0.90".
> > 
> >       If more pre-releases are needed, we would then increase
> >       the MICRO number, so "GDB 9.0.91", GDB "9.0.92", etc.
> >       Note that additional pre-release are fairly rarely needed
> >       (but have occasionally happened, so we need to be prepared
> >       to generate them).
> > 
> >       I'll explain the use of micro numbers after the procedure
> >       is laid out (to avoid clogging the general procedure with
> >       details) [1].
> > 
> >   (c) Once the pre-release is out, the version number gets updated
> >       to include the date again, so "<N+1>.0.90.DATE".
> > 
> >   (d) The first official release off a release branch would have
> >       the MINOR number set to "1". Thus: "GDB <N+1>.1".
> > 
> >       Following that principle, our next major GDB release will be
> >       GDB 9.1.
> > 
> >   (e) Once the GDB 9.1 release is made, we switch the branch's version
> >       to "<N+1>.1.90.DATE".
> > 
> >   (f) The next official release would be "<N+1>.2".
> > 
> >   (g) Once "<N+1>.2" is out, the version number would be set to
> >       "<N+1>.2.90.DATE" again.
> > 
> >   (h) Same principle if additional releases are needed ("<N+1>.3", etc).
> > 
> > [1] One property I wanted to have in the procedure above was to have
> >     a consistent minor number for the first official release, so as to
> >     know that GDB <X>.1 is always the first official release from branch
> >     <X>.  Combined with the potential need for multiple pre-releases,
> >     and the fact that we want to have increasing version numbers, and
> >     dated version numbers in between, the only way I found was to use
> >     the <X>.0.9X range.
> > 
> >     One alternative to using <N+1>.0.90 for pre-release would be to use
> >     <N>.90. It's a shorter version number, and I would be OK with that,
> >     but my sense is that it's kind of confusing that a pre-release
> >     would have a different major version.
> > 
> > [2] Minor note: In the majority of the release cycles, we create the first
> >     pre-release right after the branch is cut. However, there have been
> >     cycles in the past were we wanted to wait for specific fixes before
> >     creating the first pre-release. In those situations, the first
> >     pre-release will be "<N+1>.0.91" instead. I don't think it really
> >     is all that important.
> > 
> > Thoughts? If we agree, I will update gdb/version.in, and look at the
> > documentation update.
> > 
> > -- 
> > Joel
> 
> -- 
> Joel