Janneke Nieuwenhuizen <janneke@gnu.org> writes:

>> Also, from the diagrams in [1][2][3] it looks like the full-source bootstrap
>> uses tarballs frozen in time (make-3.80, gcc-2.95.3, gcc 4.7.3, etc.). So,
>> even if newer versions of 'make' or 'gcc' will use a Python-based gnulib-tool,
>> there won't be a problem, because the bootstrap of these old tarballs will
>> be unaffected.
>
> indeed.  For the current situtation (that's less than great and are
> working on to resolve), making essential GNU packages less
> bootstrappable is of no consequence.  Cleaning-up the full-source
> bootstrap and making it more or less future-proof, might be challenged
> by such a new dependency.

Rather than finding out what dependencies are problematic through
tedious manual work, is there a recommendation we can articulate that
would help the bootstrappable effort?

For example, in Libtasn1 (which I guess is fairly low in the
bootstrapping graph) I made the CI/CD pipeline [1] build the tarball on
Debian 4 etch (2010, first amd64 release), and using 'pcc' and 'tcc' as
alternative C compilers.  I'm hoping this has some value, but I have no
good way to tell.  What actual testable environments would it make sense
to test a project in, to help the bootstrappable effort?  Right now
these targets build fine, but if at some point 'pcc' stops building, I
may be inclinced to simply drop this target rather than to fix the bugs
since I have no idea if supporting building with 'pcc' helps anyone.

I'm thinking suggestions like 'Build and test project on i386 Debian 3',
or 'Cross-build project from amd64 to mipsel on Debian 4'.  I can't seem
to find docker images for CentOS 3-6, maybe old CentOS is a good
long-term target too.  If there were concrete fact-based suggestions
like that, I would make an effort to CI/CD build libidn, libidn2,
inetutils, and some other projects to make sure they continue to work on
old platforms.

/Simon

[1] https://gitlab.com/gnutls/libtasn1/-/pipelines/