I see little reason to support old OCaml releases and requiring OCaml 4.06 would be fine with me but I assume that the project might have its own ideas about this.
________________________________________ From: Edwin Torok Sent: 18 August 2020 08:28 To: Christian Lindig; xen-devel@lists.xenproject.org Cc: Ian Jackson; d...@recoil.org; w...@xen.org Subject: Re: [PATCH v1 0/6] tools/ocaml/xenstored: simplify code On Mon, 2020-08-17 at 14:56 +0200, Christian Lindig wrote: > This all looks good - I left a small comment on one of the patches > and I agree that this needs testing. I also wonder about > compatibility with earlier OCaml releases that we support but I see > no real obstacles. > I've developed the series using OCaml 4.08.1. I think the newest feature I used was Map.update (OCaml 4.06, nearly 3 years ago). Looking through https://repology.org/project/ocaml/versions I'm not sure if we can require more than 4.05 though. The README in Xen doesn't specify a minimum version, but configure checks for >=4.02. I can try to backport my series to OCaml 4.05 (to use Map.find_opt instead of Map.update) and update the configure check to require 4.05. It would be possible to backport even further to 4.02 by introducing additional inefficiencies (Map.mem + Map.find would traverse the map twice, and Map.find on its own would raise an exception on Not found, which is more costly than returning None in Map.find_opt), I'd avoid doing that. Xen's CI from automation might need some updates to use latest stable versions: * Fedora 29 is EOL, should use at least Fedora 31 * Debian Jessie is EOL. Stretch is present, but Buster is missing Best regards, --Edwin
