[bug#51845] [CORE-UPDATES] librsvg and rust

[Ludovic Courtès]

Hello!

For the record, this is a followup to Efraim’s proposal in
<https://issues.guix.gnu.org/51845>.

Efraim Flashner <efraim@flashner.co.il> skribis:

> Option 1:
> Track down the ~220 crates which form the dependency graph (of crates)
> for librsvg and pin them until the next core-updates cycle. Continue
> like with other packages and add newer versions (like cmake or meson) as
> packages need them.¹

The advantage of this approach is that we could do it incrementally: we
could merge ‘core-updates-frozen’ today and just add pinned variants of
these 200+ crates as needed as time passes.  The downside is that it’s a
lot of crates to take care of, and we might still accidentally overlook
seemingly innocuous crate upgrades that end up causing major rebuilds.

> Option 2:
> Use the bundled crates and treat it as just part of the librsvg source
> code.²
>
> Option 2b:
> Use the bundled crates for now to finish with core-updates-frozen and
> revisit this immediately on core-updates (not frozen).

This option will involved a rebuild on x86_64, but the advantage is that
we’ll be safe going forward: we won’t accidentally cause world rebuilds
just because an obscure crate somewhere has been upgraded.

[...]

> I'm currently leaning option 2b, it'll get us past this hurdle for
> core-updates-frozen and let us make changes to the crates as we work to
> integrate them more fully into Guix.

Same here; it’s not ideal, but it seems like the most reasonable
short-term option.

If there are no objections, I’d suggest that you go ahead with this
plan.

Thanks for keeping the ball rolling!

Ludo’.