GHC 9.8 and Cabal 3.10.3 on Gentoo Linux

:: gentoo, haskell, programming language, system, tutorial

By: Maciej Barć

The official ::gentoo repository currently contains only GHC on version 9.2.8. To install newer GHC one has to either download/build themselves or use the ::haskell overlay (https://github.com/gentoo-haskell/gentoo-haskell).

Enable the ::haskell overlay

Enable:

eselect repository enable haskell

Sync:

emerge --sync haskell
egencache --update --repo haskell --jobs 12 --load 6
eix-update

Unmask needed packages

Add to /etc/portage/package.unmask/0000_hs.conf

<dev-lang/ghc-9.9

<dev-haskell/cabal-3.11
<dev-haskell/cabal-install-3.11
<dev-haskell/cabal-install-solver-3.11
<dev-haskell/cabal-syntax-3.11
<dev-haskell/text-2.2
<dev-haskell/parsec-3.1.18

Add to /etc/portage/package.accept_keywords/0000_hs.conf

app-admin/haskell-updater
dev-haskell/*
dev-lang/ghc

Install

emerge --ask --verbose ">=dev-lang/ghc-9.8" ">=dev-haskell/cabal-install-3.10"

Build of GHC 9.8 takes around ~2 hours on a 8-core laptop-grade CPU.

Bonus: masking packages from ::haskell

If you want to exclude a given version from the ::haskell overly from being installed/updated, then you can add a similar line(s) to /etc/portage/package.mask/0000_hs.conf:

app-emacs/haskell-mode::haskell