cabal freeze fails with some GHC versions due to missing Distribution.Compat.Typeable

[debug-ito]

I used cabal-install-3.12.1.0, and found a problem in cabal freeze.

To reproduce

• Install ghc-9.2.1 and cabal-install-3.12.1.0 by ghcup.
• Clone https://github.com/debug-ito/greskell.git and checkout cba2d6c9dddbf24adf9901dd9b6b0d48356df70c (EDITED: checking out this specific commit is necessary, because it contains cabal.project with allow-newer: all)
• Run cabal freeze.

Then I got the following error.

Error:
    Problem with module re-exports:
      - The module 'Distribution.Compat.Typeable'
        is not exported by any suitable package.
        It occurs in neither the 'exposed-modules' of this package,
        nor any of its 'build-depends' dependencies.
    In the stanza 'library'
    In the package 'Cabal-3.12.1.0'

It looked like cabal tried to evaluate metadata of Cabal-3.12.1.0 with Cabal-syntax-3.14.0.0 in mind, and complained that Distribution.Compat.Typeable was missing.

See also: One of my GitHub CI runs

System information

I used Xubuntu Linux 22.04 64-bit.

Affected GHC versions

According to my experiments, the following GHC versions had this bug.

• 9.2.1
• 9.6.1
• 9.8.1

The following GHC versions didn't have this bug.

• 9.4.1
• 9.10.1

Struggle

I tried running cabal freeze -c 'Cabal==3.12.0.0' -c 'Cabal-syntax==3.12.0.0' with ghc-9.2.1, but it had the same issue.
I also tried writing the equivalent constraints stanza in cabal.project.local or cabal.project.freeze, but it had the same issue.

Any ideas? Is there any way to run cabal freeze with ghc-9.2.1?

[effectfully]

I'm running into the same problem with the same cabal version (3.12.1.0) and GHC-9.6.6. Ubuntu 20.04.

[ulysses4ever]

Thanks for the report and independent reproduction!

Could you check if cabal-3.10 suffers the same?

[debug-ito]

I tried cabal-install-3.10.1.0 and cabal-install-3.10.3.0 with ghc-9.2.1, but had the same error.

[harryaskham]

I was seeing this same issue the last few weeks, but only on my aarch64-linux NixOS machines (a VPS and a nix-on-droid install). A number of similarly configured x86 machines are fine on the same versions of GHC / Cabal / surrounding machinery (the config is identical from machine to machine, only nixpkgs itself changes).

GHC 9.8.1
Cabal 3.12.1.0
nixpkgs following unstable

I figured it out in my case while typing this: I had the following in my cabal.project which was needed I believe in order to use Cabal 3.12 when it was in prerelease:

-- For Cabal 3.12 prerelease
allow-newer:
  *:Cabal,
  *:Cabal-syntax

I'd added this to most of my projects so I could use multi-repl as soon as it dropped. Removing this on cabal 3.12.1.0 fixed things for me.

[debug-ito]

Thanks for valuable input. I think allow-newer was part of the cause.

When I got the error, my cabal.project had allow-newer: all to try testing with some new packages. I updated the original description so that the "To reproduce" section referred to the right commit that had allow-newer: all.

When I removed the allow-newer: all from cabal.project, cabal freeze succeeded.