support ghc-9.0: base-4.15 and template-haskell-2.17

[juhp]

Just a ticket to track support for ghc-9.0

base-4.15.0.0 (changelog) is out of bounds for:

• hackage-security-0.6.0.1 (>=4.5 && < 4.15). GHC 9 bounds issues, Grandfathered dependencies. @haskell. Used by: library

template-haskell-2.17.0.0 (changelog) is out of bounds for:

• hackage-security-0.6.0.1 (>=2.7 && < 2.17). GHC 9 bounds issues, Grandfathered dependencies. @haskell. Used by: library

[Mikolaj]

I think this fixed now on master branch and I'm going to release RSN. Could you check the current codebase works for you and nothing extremely urgent is missing? Thank you!

[juhp]

Thank you!

I mostly filed this on behalf of Stackage - probably should be fine to go ahead and release it.
I think if cabal-install and pantry can build with this version it should be good to go.

You could also add ghc-9.0 to the GH action:
eg ghc: ['9.0', '8.10', '8.8', '8.6']
(possibly dropping 8.6 is you don't want too many jobs there).

[juhp]

Ah so I tested trying my cabal-file project and hit:

ghc-prim-0.7.0 (changelog) is out of bounds for:

• ed25519-0.0.5.0 (>=0.1 && < 0.7). Grandfathered dependencies, Library and exe bounds failures. @thoughtpolice. Used by: library

[juhp]

So I opened thoughtpolice/hs-ed25519#30 ...

[juhp]

That one is already fixed now

[juhp]

And now I can build cabal-file with your repo

[Mikolaj]

\o/

[juhp]

Of course cabal-install can't build with ghc9 yet...

[Mikolaj]

Actually it should, soon, once this PR is merged: haskell/cabal#7907