stdlib-shims: fails to build on 4.12.0+trunk

[avsm]

upstream fix proposed at ocaml/stdlib-shims#17

[dra27]

This was fixed in Dune in ocaml/dune#3576

[avsm]

Sounds like we need to conflict this with dune < 2.7 and ocaml <4.12 then

[avsm]

does 241ff77 look right @dra27?

[camelus]

Commit: e855240

A pull request by opam-seasoned @avsm.

☀️ All lint checks passed e855240

• These packages passed lint tests: stdlib-shims.0.1.0

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☀️ Installability check (+0)

[hannesm]

I'm curious whether dune < 2.7.0 should require ocaml < 4.12.0, and not bother with constraining stdlib-shims at all... since it looks to me that more packages (all with empty modules) will encounter this issue...

[dra27]

@hannesm is correct! Are you aware of any packages which would be affected by this change, though - it's not empty modules, but empty libraries (i.e. a library with no modules)

[avsm]

We'll find this out soon enough when we start doing bulk tests on 4.12. I suspect the current restriction is fine, and we can apply the big dune restriction if there turn out to be a non-trivial number of affected packages.

[mseri]

Should we merge this or you prefer to wait? In the end it is a small change to keep the issue under control, it seems a reasonable start

[avsm]

Agreed. I'll merge go ahead and merge this, and it can be tested with #17005