Bootstrap of version 3.8.1.0 fails on macOS

[essandess]

Describe the bug

I'm the maintainer for the MacPorts cabal port and am trying to update to version 3.8.1.0.

I'm following the revised bootstrap instructions on https://github.com/haskell/cabal/blob/master/bootstrap/README.md#bootstrapping-cabal-install and am hitting this issue. The cabal binary is downloaded from https://downloads.haskell.org/~cabal/cabal-install-3.8.1.0/.

cabal new-update
cabal new-configure

cd ./bootstrap
cabal v2-run -v0 cabal-bootstrap-gen -- darwin-9.2.1.plan.json | tee darwin-9.2.1.json

The cabal error prior to the tee output is:

Error: cabal: Could not resolve dependencies:
[__0] trying: cabal-bootstrap-gen-0 (user goal)
[__1] next goal: base (dependency of cabal-bootstrap-gen)
[__1] rejecting: base-4.16.0.0/installed-4.16.0.0 (conflict:
cabal-bootstrap-gen => base^>=4.12.0.0 || ^>=4.13.0.0 || ^>=4.14.0.0)
[__1] skipping: base-4.15.0.0 (has the same characteristics that caused the
previous version to fail: excluded by constraint '^>=4.12.0.0 || ^>=4.13.0.0
|| ^>=4.14.0.0' from 'cabal-bootstrap-gen')
[__1] rejecting: base-4.14.1.0, base-4.14.0.0, base-4.13.0.0, base-4.12.0.0,
base-4.11.1.0, base-4.11.0.0, base-4.10.1.0, base-4.10.0.0, base-4.9.1.0,
base-4.9.0.0, base-4.8.2.0, base-4.8.1.0, base-4.8.0.0, base-4.7.0.2,
base-4.7.0.1, base-4.7.0.0, base-4.6.0.1, base-4.6.0.0, base-4.5.1.0,
base-4.5.0.0, base-4.4.1.0, base-4.4.0.0, base-4.3.1.0, base-4.3.0.0,
base-4.2.0.2, base-4.2.0.1, base-4.2.0.0, base-4.1.0.0, base-4.0.0.0,
base-3.0.3.2, base-3.0.3.1 (constraint from non-upgradeable package requires
installed instance)
[__1] fail (backjumping, conflict set: base, cabal-bootstrap-gen)
After searching the rest of the dependency tree exhaustively, these were the
goals I've had most trouble fulfilling: base, cabal-bootstrap-gen

Expected behavior

I expect the file darwin-9.2.1.json to be created to be able to bootstrap cabal on macOS.

System information
macOS 12.5 21G72 x86_64
Xcode 13.4.1 13F100

cabal-install version 3.8.1.0
compiled using version 3.8.1.0 of the Cabal library

The Glorious Glasgow Haskell Compilation System, version 9.2.1

[Mikolaj]

That you for the report. The bounds on cabal-bootstrap-gen seem to be outdated. A workaround is to compile cabal-bootstrap-gen with an older GHC and execute the compiled version (possible while GHC is set to a new one; I don't know it that matters). A proper fix would be to relax bounds in the .cabal file for `cabal-bootstrap-gen to include all new GHCs up to 9.4.

[robx]

You shouldn't need to regenerate the bootstrap files, I believe we check that the linux bootstrap files are good for bootstrapping macOS in CI. Instead, you should be able to bootstrap using the normal bootstrapping command,

./bootstrap/bootstrap.py -d ./bootstrap/linux-ghcver.json -w /path/to-ghc

[Mikolaj]

Oh, I didn't think about that. @essandess: please let us know if that works in your case.

@robx: I don't remember if I asked you and I can't find you on IRC/Matrix: would you like to drop in sometimes into the fortnightly cabal dev's chats (starts in 40min)?

[essandess]

please let us know if that works in your case.

Thanks for the suggestions. Unfortunately, swapping in linux-9.2.3.json doesn't work for ghc version 9.2.1:

ghc-pkg: cannot find package base-4.16.2.0

We have explicitly not updated ghc beyond version 9.2.1 yet because these versions require the Haskell build tool hadrian and we (I) just haven't gotten around to figuring out how to build and use hadrian to bootstrap ghc. When we do, ghc's latest version is 9.4.1, which isn't in the predefined linux-*.json files in the cabal bootstrap directory.

Is there an alternate approach by simply ripping out the version requirements in cabal-bootstrap-gen.cabal? Any suggestion on which requirements to relax, or simply remove all of them?

[essandess]

Is there an alternate approach by simply ripping out the version requirements in cabal-bootstrap-gen.cabal? Any suggestion on which requirements to relax, or simply remove all of them?

That apparently doesn't work either. Simply removing all the requirements from cabal-bootstrap-gen.cabal yields the error:

> :info:build src/Main.hs:39:11: error:
> :info:build     • Couldn't match expected type: Map.Map C.PackageName I.PackageI
nfo
> :info:build                   with actual type: (FilePath, Map.Map C.PackageName
 I.PackageInfo)
> :info:build     • In the first argument of ‘main2’, namely ‘meta’
> :info:build       In a stmt of a 'do' block: main2 meta plan
> :info:build       In the expression:
> :info:build         do meta <- I.cachedHackageMetadata
> :info:build            plan <- P.decodePlanJson planPath
> :info:build            main2 meta plan
> :info:build    |
> :info:build 39 |     main2 meta plan
> :info:build    |           ^^^^

[Mikolaj]

Any suggestion on which requirements to relax, or simply remove all of them?

I think just add base-4.16 and actually all other base version up to the one in GHC 9.4, in the same way older base version ranges are specified so far. If that works, we'd accept this as a PR.

[Mikolaj]

BTW, I think there is a linux-9.2.1.json somewhere in the repo history, half a year ago perhaps.

[essandess]

linux-9.2.1.json

BTW, I think there is a linux-9.2.1.json somewhere in the repo history, half a year ago perhaps.

Thanks, but no such luck:

git log --all --full-history -- "*linux-9.2.1.json*"

I'll try setting the version on base-4.16 and failing that, move over to work on bootstrapping the latest ghc with hadrian.

[essandess]

I've updated to ghc-9.4.1. All approaches discussed to bootstrap cabal appear to fail:

Using linux-9.2.3.json:

:debug:build system -W /opt/local/var/macports/build/_opt_local_ports_lang_cabal
/cabal/work/cabal-install-3.8.1.0: ./bootstrap/bootstrap.py -d ./bootstrap/darwi
n-9.4.1.json -w /opt/local/bin/ghc
:info:build ghc-pkg-9.4.1: cannot find package ghc-prim-0.8.0

Trying to build darwin-9.4.1 per the instructions:

:debug:build system -W /opt/local/var/macports/build/_opt_local_ports_lang_cabal/cabal/work/cabal-install-3.8.1.0: /opt/local/var/macports/build/_opt_local_ports_lang_cabal/cabal/work/bin/cabal v2-build --with-compiler=/opt/local/bin/ghc --dry-run cabal-install:exe:cabal
:info:build Resolving dependencies...
:info:build Error: cabal: Could not resolve dependencies:
:info:build [__0] trying: Cabal-3.8.1.0 (user goal)
:info:build [__1] trying: base-4.17.0.0/installed-4.17.0.0 (dependency of Cabal)
:info:build [__2] trying: Cabal-described-3.8.1.0 (user goal)
:info:build [__3] next goal: rere (dependency of Cabal-described)
:info:build [__3] rejecting: rere-0.2 (conflict: base==4.17.0.0/installed-4.17.0.0, rere
:info:build => base>=4.3.0.0 && <4.17)
:info:build [__3] skipping: rere-0.1 (has the same characteristics that caused the
:info:build previous version to fail: excludes 'base' version 4.17.0.0)

[Mikolaj]

Yes, linux-9.2.3.json has no chance to work with GHC 9.4. I wonder, perhaps spin a Linux VM, generate linux-9.2.1.json on that (make something-bootstrap) and copy over?