Bug#1056033: ghc: Please include patch to fix cabal arch detection for sparc64

[Ilias Tsitsimpis]

Hi Adrian,

On Wed, Dec 13, 2023 at 04:14PM, John Paul Adrian Glaubitz wrote:
> On Thu, 2023-11-16 at 20:23 +0200, Ilias Tsitsimpis wrote:
> > Thanks for working on this. I fear that applying this patch will change
> > the ABI for Cabal, and hence we will have to rebuild every Haskell
> > package in Debian. Because of that, I plan on waiting for the current
> > transition to finish, and then include this patch in the next GHC
> > upload.
> 
> Are you sure that this actually the case [1]?
> 
> > [1] https://github.com/haskell/cabal/pull/9445#issuecomment-1811780089

In the issue they are discussing something different, whether they need
to bump the version of the API spec for Cabal.

What I meant is that modifying the code of any Haskell library (in our
case Cabal) changes the resulting ABI hash, and then we need to rebuild
any package that depends on it. In general this is not a big issue, we
would just rebuild everything, but I would like to avoid it now that we
are so close to finish this transition.

I have verified that applying your patch results in a different ABI hash
for libghc-cabal-dev. You can verify it yourself, apply the patch,
rebuild and compare the resulting binary packages.

Best,

-- 
Ilias