On Thu, Dec 07, 2023 at 12:53:02PM +0000, Richard Eisenberg wrote:

I think this is an excellent idea! So excellent, that we've already done it. :)

When I try to compile with GHC 9.6.2 (what I have lying around), GHC2021 is in effect.

Is there something different you were thinking of?

I think Arnaud meant that compilations of GHC's codebase itself should use the GHC2021 setting.

On a whim tried enabling it by default but it failed first because GeneralizedNewtypeDeriving is incompatible with safe haskell and once I disabled GeneralizedNewtypeDeriving it failed with some error about missmatched kinds. I would welcome a patch doing this, but it's not a priority. Especially since it doesn't seem to be as simple as changing the base language and removing some pragmas. Am 07/12/2023 um 14:29 schrieb Arnaud Spiwack:

Indeed. I didn't realise the ambiguity in my wording.

I'd like for GHC to be built, with Hadrian, using GHC2021 as the base language.

On Thu, 7 Dec 2023 at 14:01, Tom Ellis wrote:

On Thu, Dec 07, 2023 at 12:53:02PM +0000, Richard Eisenberg wrote: > I think this is an excellent idea! So excellent, that we've already done it. :) > > When I try to compile with GHC 9.6.2 (what I have lying around), GHC2021 is in effect. > > Is there something different you were thinking of?

I think Arnaud meant that compilations of GHC's codebase itself should use the GHC2021 setting. _______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs

-- Arnaud Spiwack Director, Research at https://moduscreate.com and https://tweag.io.

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Thanks Oleg. I quite like what I'm seeing there! On Fri, 8 Dec 2023 at 18:36, Oleg Grenrus wrote:

I think Arnaud was talkin about ghc, i.e. compiler/, not about everything (incl libraries/base e.g.).

I tried, the PoC is at https://gitlab.haskell.org/ghc/ghc/-/merge_requests/11743

I needed to do `NoPolyKinds` in few modules (could give kind signature too, but NoPolyKinds were quicker). Especially that hits hs-boot files.

By doing `default-language: GHC2021`, and going through modules with BangPatterns (and removing that, and other GHC2021 extensions), the diff stats are nice: 91 files changed, 24 insertions(+), 272 deletions(-)

- Oleg On 8.12.2023 13.33, Andreas Klebinger via ghc-devs wrote:

On a whim tried enabling it by default but it failed first because GeneralizedNewtypeDeriving is incompatible with safe haskell and once I disabled GeneralizedNewtypeDeriving it failed with some error about missmatched kinds.

I would welcome a patch doing this, but it's not a priority. Especially since it doesn't seem to be as simple as changing the base language and removing some pragmas. Am 07/12/2023 um 14:29 schrieb Arnaud Spiwack:

Indeed. I didn't realise the ambiguity in my wording.

I'd like for GHC to be built, with Hadrian, using GHC2021 as the base language.

On Thu, 7 Dec 2023 at 14:01, Tom Ellis < tom-lists-haskell-cafe-2023@jaguarpaw.co.uk> wrote:

...

On Thu, Dec 07, 2023 at 12:53:02PM +0000, Richard Eisenberg wrote:

...

I think this is an excellent idea! So excellent, that we've already done it. :)

When I try to compile with GHC 9.6.2 (what I have lying around), GHC2021 is in effect.

Is there something different you were thinking of?

I think Arnaud meant that compilations of GHC's codebase itself should use the GHC2021 setting. _______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs

-- Arnaud Spiwack Director, Research at https://moduscreate.com and https://tweag.io.

_______________________________________________ ghc-devs mailing listghc-devs@haskell.orghttp://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs

_______________________________________________ ghc-devs mailing listghc-devs@haskell.orghttp://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs

_______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs

-- Arnaud Spiwack Director, Research at https://moduscreate.com and https://tweag.io.