ghcWithPackages is broken after #32112

[peti]

I can no longer create a non-trivial ghcWithPackages environment in e5e3282. For example:

$ nix-shell -p "haskellPackages.ghcWithPackages (ps: with ps; [conduit])"
these derivations will be built:
  /nix/store/cjii0g4dchv428b7hphywhiiic0330ls-ghc-8.0.2-with-packages.drv
building path(s) ‘/nix/store/7npnrjwfq2pqv4nrhx7wqx7wshzsbxp6-ghc-8.0.2-with-packages’
/nix/store/b7khbp6npknqdlfbazflqdq93fky7884-primitive-0.6.2.0/nix-support:
propagated-build-inputs: /nix/store/ncsa1515gj4mqpph7x5dni3x7sialzcw-resourcet-1.1.9/nix-support/propagated-build-inputs
/nix/store/ykrvhpmf86mf0iv9dkyinfmawj70rpki-mmorph-1.0.9/nix-support:
propagated-build-inputs: /nix/store/ncsa1515gj4mqpph7x5dni3x7sialzcw-resourcet-1.1.9/nix-support/propagated-build-inputs
/nix/store/zg4vysxznfwbzjig56b9zm41k79mv27y-transformers-base-0.4.4/nix-support:
propagated-build-inputs: /nix/store/ncsa1515gj4mqpph7x5dni3x7sialzcw-resourcet-1.1.9/nix-support/propagated-build-inputs
/nix/store/zlmn0ybpz335czi083g8v2ky7jw2y635-monad-control-1.0.2.2/nix-support:
propagated-build-inputs: /nix/store/ncsa1515gj4mqpph7x5dni3x7sialzcw-resourcet-1.1.9/nix-support/propagated-build-inputs
/nix/store/i25283yd7r99x652nkpgwnlw4w0hbkmh-lifted-base-0.2.3.11/nix-support:
propagated-build-inputs: /nix/store/ncsa1515gj4mqpph7x5dni3x7sialzcw-resourcet-1.1.9/nix-support/propagated-build-inputs
/nix/store/xbbc5dl4hi0iana1a96rwiv2rc013ack-transformers-compat-0.5.1.4/nix-support:
propagated-build-inputs: /nix/store/ncsa1515gj4mqpph7x5dni3x7sialzcw-resourcet-1.1.9/nix-support/propagated-build-inputs
/nix/store/bc5lsl0zj1kzacl6cfr05nn9pv7p4sak-stm-2.4.4.1/nix-support:
propagated-build-inputs: /nix/store/ncsa1515gj4mqpph7x5dni3x7sialzcw-resourcet-1.1.9/nix-support/propagated-build-inputs
/nix/store/1rk7rxadvbaj98rs6wlxmh20s9ac95rb-mtl-2.2.1/nix-support:
propagated-build-inputs: /nix/store/ncsa1515gj4mqpph7x5dni3x7sialzcw-resourcet-1.1.9/nix-support/propagated-build-inputs
/nix/store/x0kpi6705zfap9byp8jw5lfh5qrkibd3-exceptions-0.8.3/nix-support:
propagated-build-inputs: /nix/store/ncsa1515gj4mqpph7x5dni3x7sialzcw-resourcet-1.1.9/nix-support/propagated-build-inputs
There are problems in package conduit-1.2.12.1:
  dependency "exceptions-0.8.3-ADEDRATtUrMK1JW4zMQ9U" doesn't exist
  dependency "lifted-base-0.2.3.11-Ei0JSPdt7KOCD2HIA5jFqV" doesn't exist
  dependency "mmorph-1.0.9-5bASEvmIkr5CpdAYXwPsn0" doesn't exist
  #25537dependency "monad-control-1.0.2.2-1Ci8dYJ8Tb7E3HTcTqOb8l" doesn't exist
  dependency "mtl-2.2.1-BLKBelFsPB3BoFeSWSOYj6" doesn't exist
  dependency "primitive-0.6.2.0-4578caNkWQ54Gt1mxLF2Yh" doesn't exist
  dependency "resourcet-1.1.9-L2BUQrxWZMwDiwhcuyPuNi" doesn't exist
  dependency "transformers-base-0.4.4-GKSs0LKukAL8ymq2naFmrH" doesn't exist
  dependency "transformers-compat-0.5.1.4-IuFogs8HAVUJBWVNMhtssu" doesn't exist

The following packages are broken, either because they have a problem
listed above, or because they depend on a broken package.
conduit-1.2.12.1
builder for ‘/nix/store/cjii0g4dchv428b7hphywhiiic0330ls-ghc-8.0.2-with-packages.drv’ failed with exit code 1
error: build of ‘/nix/store/cjii0g4dchv428b7hphywhiiic0330ls-ghc-8.0.2-with-packages.drv’ failed
/run/current-system/sw/bin/nix-shell: failed to build all dependencies

This seems related to #32112?

Ping @nc6, @domenkozar.

[nc6]

@peti This works fine for me on that branch:

[nc@varda:~/nixpkgs.hask-split-out]$ nix-shell -p "haskellPackages.ghcWithPackages (ps: [ps.conduit])" -I .

[nix-shell:~/nixpkgs.hask-split-out]$ ghci
GHCi, version 8.0.2: http://www.haskell.org/ghc/  :? for help
Loaded GHCi configuration from /home/nc/.ghc/ghci.conf
λ> import Data.Conduit
(0.02 secs, 0 bytes)

If it's broken in master, I assume it's some other commit that's broken it.

[peti]

I responded in #32112 (comment).