[GHC DevOps Group] Fwd: Release policies

[Boespflug, Mathieu]

On 15 December 2017 at 16:32, Ben Gamari <ben at well-typed.com> wrote:
> "Boespflug, Mathieu" <m at tweag.io> writes:
>
>> Thanks for the feedback, Michael.
>>
>> Manuel, I believe you are also a Cabal-the-library consumer in Haskell For Mac?
>>
>> Michael, you brought up another problem tangentially related to the
>> original integer-gmp issue but that was not in my original list
>> earlier in this thread:
>>
>> * Cabal-2.0.0 had breaking changes in the API.
>>
>> This means that by association GHC itself broke BC, because it shipped
>> with Cabal-2.0, without the usual grace period.
>>
> I'm a bit confused; by "the usual grace period" do you mean the Core
> Library Committee's three release policy?

I did mean that one, yes. That was my question earlier - is Cabal
along with *all* core libraries covered by the CLC's 3-release policy?

The *Core Libraries* Committee (CLC) defines a "core library" as

"Our definition of "core library" is a library that ships with GHC."
(See https://wiki.haskell.org/Library_submissions#The_Libraries)

But indeed, Cabal is not part of the CLC libraries list on that page.
So I'm confused too: a) is Cabal a "core library", b) does that mean
Cabal is bound by the 3-release policy?

> GHC has never, as far as I am aware, considered major version bumps of
> its dependencies to be part of its interface. We perform a major bump of
> most libraries with nearly every release [1].

Yes, and major version bumps are not necessarily BC.