Build errors using GHC 9.8 due to missing (GHC-internal) library system-cxx-std-lib

[raehik]

Upon trying to use basePackages = pkgs.haskell.packages.ghc98 (on haskell-updates, and the branch over here NixOS/nixpkgs#260138 ), I get the following error:

error:
       … while evaluating the attribute 'optionalValue.value'

(snip)

       error: function 'anonymous lambda' called without required argument 'system-cxx-std-lib'

       at /nix/store/q5p1xzzh61gb91k5y3zy3jj6w956frpc-source/pkgs/development/haskell-modules/hackage-packages.nix:1540:6:

         1539|   "BesselJ" = callPackage
         1540|     ({ mkDerivation, base, gamma, numerical-integration
             |      ^
         1541|      , system-cxx-std-lib, tasty, tasty-hunit

On a quick glance, this is a GHC thing, which may have existed since GHC 9.4. input-output-hk/haskell.nix#1939

The nixpkgs branch I linked above has a comment stating that building the compiler/pkgset worked. Is there something in haskell-flake that's breaking the build?

Testing here: raehik/generic-data-functions#3

[srid]

error: function 'anonymous lambda' called without required argument 'system-cxx-std-lib'

Errors like this typically mean that the specified package is not in the package set. That is to say, there is no pkgs.haskell.packages.ghc98.system-cxx-std-lib.

haskell-flake works with your basePackages as-is, except for merging your packages/settings as overlays; see

haskell-flake/nix/modules/project/outputs.nix

Lines 86 to 91 in 63a1608

	finalOverlay = lib.composeManyExtensions [
	config.packagesOverlay
	config.settingsOverlay
	];
	finalPackages = config.basePackages.extend finalOverlay;

[raehik]

I made this issue assuming the package set was configured properly, but I think I might have been wrong. I added system-cxx-std-lib = null; to configuration-ghc-9.8.x.nix, and it seems to be building fine. Thanks for the help. (Also sorry I tend to make issues over discussions, habit -- I'll remember for next time!)