Friday 8 November 2019

archive openings are not always fun (not forwarded issues, and ftbfs left over from the previous series)

Opening a new development series, syncing packages from Debian again, and having
multiple entangled transitions ongoing is not always fun, but we need to handle
that. While working on those I see two kind of issues which could be improved.

Seeing an Ubuntu delta which is not forwarded to Debian. When introducing an
Ubuntu delta (which itself isn't a bad idea), it is not necessary to immediately
forward an issue, and some of these fixes seem to be made during release times
when people are busy. It would be much simpler to sync an applied fix from
Debian, removing the delta.

When we introduce new upstream versions, either by syncing from experimental, or
by going ahead in Ubuntu, we don't fix, and we don't even check for regressions
introduced by these changes. It's easier to see and track when autopkg tests
fail, but not so much, when the package starts to ftbfs, and the first time you
discover and have to fix is, are unrelated transitions. We have the ftbfs
information in form of the test rebuilds, and this can be used to check for
common ftbfs. Examples are:

- recent glibc versions: removed header files, or newly implemented
syscall wrappers. These are one or two common error messages, which
can be grepped for.

- glib2.0/gtk syncs from experimental, deprecating functions. Again,
a common error, which can be grepped for.

- linux-libc-dev: A new upstream version usually introduces different
issues, some may be general, but maybe not enough to grep for them.

I am also aware that introducing new compiler versions creates new ftbfs issues.
These are usually known in advance by doing test rebuilds, explicit bug
reports in LP for main, and filing issues for Debian. Not perfect either.

Attaching a small shell script to download the logs for failed builds from a
ftbfs-report. Feel free to experiment what you can discover by just grepping
the build logs.

Matthias