Re: [Caml-list] OPAM: retiring 3.12.1 testing?

[Anil Madhavapeddy <anil@recoil.org>]

On 16 Feb 2015, at 11:21, Török Edwin <edwin+ml-ocaml@etorok.net> wrote:
> 
> On 02/16/2015 01:04 PM, Anil Madhavapeddy wrote:
>> Dear OCaml list,
>> 
>> We are currently testing the following compiler versions on every pull request to OPAM;
>> 
>> - OCaml 3.12.1
>> - OCaml 4.00.1
>> - OCaml 4.01.0
>> - OCaml 4.02.0
>> 
>> We will shortly have to test 4.02.1, and would also like to test trunk snapshots of the
>> compiler as an "allowed failure".
>> 
>> Running 6 compiler revisions per package puts quite a bit of stress on our Travis CI
>> resources, and so it's probably time to retire OCaml 3.12.1 from the testing matrix.
>> 
>> Before we do this, I'd like to get a sense for how many people still care about ensuring
>> that their packages work well on the 3.12.1 series, or if there are still distributions
>> for which this support matters.  If there is still sufficient interest, we can continue
>> to support 3.12.1 for some time.
> 
> Debian's latest stable (Wheezy) has 3.12.1, and the next release Jessie has 4.01.0 and there is an RC1 installer for it, but AFAIK there is no fixed release date when Jessie becomes stable.
> Would be nice to have 3.12.1 tests until Jessie becomes stable, but OTOH there are quite a few packages already that only build with >=4.x
> and if one wants to build them on 3.12.1 they require some minor patches already.

That's a good point.  We'll just have to keep 3.12.1 in the matrix until Jessie rotates in and has a settling period.

> Does OPAM support conditionally applying patches? (i.e. only apply patch if compiler_ver <= 4.00.0)

It does; just add a constraint on `ocaml-version` to the `patches` field.  For example, see:

https://github.com/ocaml/opam-repository/blob/master/packages/bitstring/bitstring.2.0.4/opam#L14

Patches to backport 3.12.1 support to any 4.00+ package from users are welcome.  They are minimally intrusive to users of newer compilers since the patches aren't applied unless the older compiler is used, so it's easier to merge these into the OPAM-repository.

-anil