Bug#914897: debating the wrong thing

[Ian Jackson <ijackson@chiark.greenend.org.uk>]

Ansgar Burchardt writes ("Bug#914897: debating the wrong thing"):
> Switching to (1) or (3a-with-no-support-in-buster) will mean merged-/usr
> systems would no longer be supported.  In this case someone would have
> to write a unusrmerge program to convert systems with merged-/usr to
> systems with unmerged-/usr.

Currently merged-usr is broken because it can build packages which do
not work on non-merged-usr systems.  It would be quite wrong (both
technically and socially) to react to this lack of foresight, lack of
consultation, and lack of testing, by pressing forward.

What I am suggesting in this bug report is that we revert to the
status quo before the default was changed to usrmerge, that is:

[Adam:]
>> 2. supporting both merged-usr and unmerged-usr

But actually of course "supporting" it in the way that it is currently
"supported" (according to usrmerge proponents) in stretch, sid, and
buster: if you enable it you may build packages which are not
generally useable (and perhaps you may experience other bugs).

This question is urgent for buster because the longer the current
situation continues the more systems there are that build broken
packages.

It is also urgent for stretch-backports.  The backports maintainers
have said that they want to keep stretch-backports in line with
buster.  Regardless of the wisdom of that policy, the current
situation in stretch-backports seems very bad to me.

The easiest way to fix stretch-backports (without also generating a
need to persuade the backports maintainers to waive their usual
policies) is to revert buster.


When we have stopped generating more lossage, we can start to think
about whether we want to transition to usrmerge as default, whether to
make it mandatory, and if so how the transition should be handled, and
on what timescale.

We have at least two sketches of transitions plans.  That longer-term
conversation is a much more complicated one with many more options and
many more factors.

We need the space to discuss those options properly without being
distracted by what is IMO currently a crisis in stretch-backports and
buster.


Ian.