ocaml: 4.02 -> 4.03.0

[sjmackenzie]

Motivation for this change

Tezos requires ocaml-4-03 to run: https://github.com/tezos/tezos/blob/master/scripts/install_build_deps.sh#L3

Things done

• Tested using sandboxing
  (nix.useSandbox on NixOS,
  or option build-use-sandbox in nix.conf
  on non-NixOS)
• Built on platform(s)
  • NixOS
  • OS X
  • Linux
• Tested compilation of all pkgs that depend on this change using nix-shell -p nox --run "nox-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Fits CONTRIBUTING.md.

---

[the-kenny]

is there a good reason to keep four 4.x releases of ocaml?

[sjmackenzie]

This question is a separate issue.

[sjmackenzie]

probably better to solve the your problem by opening an issue similar to this: #18111

[the-kenny]

The issue you linked is irrelevant here. This isn't about Hydra at all.

I don't think it's a separate issue, as we would have to invest more time in cleaning up if we decide that it's unnecessary to keep multiple past minor releases of ocaml.

Other than this, your 4.03.nix looks like a copy of 4.02.nix. I suggest refactoring so both use the same base as the same base and just override version and src for the respective release.

[sjmackenzie]

Your problem of too many ocaml versions is subjective, refer to ghc and llvm please. Secondly, regarding the #18111 issue, the poll I suggested you make would effectively communicate your problem to the ocaml community so they can make such a decision! Till then if you find this PR unacceptable I'll just close it immediately. Wouldn't want to add noise to signal ;-)

[sjmackenzie]

My suggestion: @the-kenny please merge this separate issue #18765 so I can refactor my PR.

[thufschmitt]

There already is a waiting pr for this (#17147), which avoids copy-pasting and adds the ocamlbuild package (which was part of the ocaml distribution until 4.02, and needed by most ocaml packages).

EDIT: typo

[sjmackenzie]

That #17147 issue has been sitting around since July 2016, If a commiter could be so kind and efficiently swoop in and merge #17147 then please close this issue. cc @7c6f434c @peti @edolstra