Matthew Pickering

@BinderDavid Well, I discovered this by trying to use a .hp file, I don't see a particular reason to remove the functionality whilst GHC still produces them by default.

The error is introduced by this function ``` 257 -- See Note [Dependencies on sublibraries] in Distribution.PackageDescription.Parsec 258 -- 259 preProcessInternalDeps :: CabalSpecVersion -> GenericPackageDescription -> GenericPackageDescription 260 preProcessInternalDeps specVer...

Setting the `cabal-version` to 3.4 resolves the roundtripping error (see first clause in preProcessInternalDeps).

Linked to https://github.com/haskell/cabal/issues/6083

Minimised reproducer: ``` cabal-version: 3.0 name: io-classes version: 1.6.0.0 library library io-classes-mtl build-depends: io-classes:{io-classes,si-timers} ```

It seems a bit baffling to me that `preProcessInternalDeps` is called only before pretty printing. I think this code can probably be deleted. It seems that is used to be...

@coot At this point it doesn't matter what you do as the cabal file which exposes the bug is in the index tarball and will never be deleted. (Not a...

I have put up a MR #10816 Let me know if you think this is along the right lines. There are already quite comprehensive checks in place for most of...