[bug#40091] [PATCH] gnu: dune: Update to 2.4.0.

[Vincent Legoll <vincent.legoll@gmail.com>]

Hello,

On Mon, Mar 16, 2020 at 8:46 PM Julien Lepiller <julien@lepiller.eu> wrote:
> Thanks for the patch! I tried using it, but even though dune builds
> fine, this new version removed support for jbuild, which creates
> build errors when building e.g. ocaml4.07-sexplib0.

Ah, that explains the build problem I met in my attempt to package
coccinelle... It surprised me since I read in the dune doc that jbuild
should be supported by dune. Maybe that doc is outdated...

> Note that according to "guix refresh -l dune" there are only 137
> dependents, so this change could go to master.

Yep, I saw that, but I also tried "guix refresh -lr" and that gave a
huge list. Maybe that's not relevant, I'm still low on the
guix / guile learning curve...

> However, we need to find a solution to the above issue.

Yes

> The guix refresh command should give you
> the list of packages that depend on dune.
> Make sure that those who
> build now still build after your patch, or fix them.

Yes

> We could also
> duplicate the dune package and uses the older dune for our
> packages that still use jbuild.

This may be the path of least resistance, and would let us
handle problems without a flag day...

> Alternatively, as suggested by dune, maybe we
> can try to run "dune upgrade" in these packages.
>
> What do you think would work best?

That is a question I cannot answer, I did not know about dune
before today ;-)

But I'll try to "dune upgrade" a few of them and we'll see where
this'll lead...

I was not expecting to fall in such a rabbit hole...
But this is fun, I'll keep at it.

-- 
Vincent Legoll