Thanks, Georgi and Sebastian.

The instructions at https://github.com/alpmestan/ghc.nix and https://ghc.dev/ seem a bit outdated, then. I’m not sure who maintains those.

In the README.md for ghc.nix, it says to run:

nix-shell https://github.com/alpmestan/ghc.nix/archive/master.tar.gz --attr devShells.<your-system>.default

That failed didn’t work for me and I was told I needed to use nix-develop, which worked.

Then later, it says to run:

$ ./boot && ./configure $CONFIGURE_ARGS # In zsh, use ${=CONFIGURE_ARGS}

…which as you pointed out should be updated to configure_ghc.

Anyway, that got me further, but I still get several fatal errors of this sort:

compiler/GHC/Tc/Zonk/Type.hs:1277:13: error:
    • Illegal equational constraint Anno
                                      (StmtLR GhcTc GhcTc (LocatedA (body GhcTc)))
                                    ~ SrcSpanAnnA
      (Use GADTs or TypeFamilies to permit this)
    • In the type signature:
        zonkStmt :: Anno (StmtLR GhcTc GhcTc (LocatedA (body GhcTc)))
                    ~ SrcSpanAnnA =>
                    (LocatedA (body GhcTc) -> ZonkTcM (LocatedA (body GhcTc)))
                    -> Stmt GhcTc (LocatedA (body GhcTc))
                       -> ZonkBndrTcM (Stmt GhcTc (LocatedA (body GhcTc)))
     |
1277 | zonkStmt :: Anno (StmtLR GhcTc GhcTc (LocatedA (body GhcTc))) ~ SrcSpanAnnA
     |             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^...
Command failed
Build failed.

Georgi, I might just ping you on Slack about it. (We’re coworkers.)

Thanks,

Lyle