cabal-install-3.8.1.0 update and sdist require ghc in PATH

[phadej]

Otherwise

Project settings changed, reconfiguring...
creating /__w/splitmix/splitmix/dist-newstyle/cache
creating /__w/splitmix/splitmix/dist-newstyle
creating /__w/splitmix/splitmix/dist-newstyle/cache
Compiler settings changed, reconfiguring...
CallStack (from HasCallStack):
  withMetadata, called at src/Distribution/Simple/Utils.hs:370:14 in Cabal-3.8.1.0-inplace:Distribution.Simple.Utils
Error: cabal-3.8.1.0: The program 'ghc' version >=7.0.1 is required but it

I guess I'm required to pass --with-compiler now?

[phadej]

Error: cabal-3.8.1.0: The program 'ghc' version >=7.0.1 is required but it could not be found.

cabal sdist is not runnable without GHC in PATH, and cabal sdist doesn't have --with-compiler option.

This is major blocker for using cabal-install-3.8.1.0.

[Mikolaj]

I don't know when it changed, but my guess would be that cabal sdist now requires GHC for some of its checks. @ffaf1: do you have any inkling?

Would enabling --with-compiler be a sufficient fix?

[phadej]

Would enabling --with-compiler be a sufficient fix?

Sufficient but ugly. Even if cabal.project supported conditionals based on compiler version, sdist could still work without knowing anything about a compiler, taking union of all possibly available packages. sdist for single package doesn't need a compiler.

[RyanGlScott]

Indeed, this prevents cabal-install-3.8.1.0 from being usable from within haskell-ci, which avoids putting compilers on the PATH by design.

[Mikolaj]

Uh, oh, cabal update needing GHC sounds definitely like a bug.

[Mikolaj]

That's a probably a release blocker. Too bad, we've already released. Are there any workarounds for haskell-ci?

A pity nobody tried 3.8.1.0-rc1 with haskell-ci. Is that reasonably easy to do for a haskell-ci user, for next time (3.8.1.0-rc1 was installable with ghcup)?

[phadej]

A pity nobody tried 3.8.1.0-rc1 with haskell-ci. Is that reasonably easy to do for a haskell-ci user, for next time (3.8.1.0-rc1 was installable with ghcup)?

I wasn't aware it was available through ghcup. It shouldn't be hard to test release candidates in the future. Though there is little insensitive as older cabal-install seems to work well enough. And that is a workaround for now: stick to using older cabal-install.