ihaskell fails to build

[vaibhavsagar]

Issue description

IHaskell is not GHC 8 compatible, and so it doesn't build on 16.09 onwards. Instead I get this error:

Setup: Encountered missing dependencies:
base >=4.6 && <4.9, ghc >=7.6 && <7.11
builder for ‘/nix/store/9bbjk1lknn94y4b7wf9wd9pfgfcfms37-ghc-parser-0.1.8.0.drv’ failed with exit code 1
cannot build derivation ‘/nix/store/ybqc2p7qk1p2i8ka889xh5ksid1xv0kn-ghc-8.0.1-with-packages.drv’: 1 dependencies couldn't be built
cannot build derivation ‘/nix/store/6mg7sz0sl6ki7r877g3agc3slqwmnlsf-ihaskell-0.8.4.0.drv’: 1 dependencies couldn't be built
building path(s) ‘/nix/store/qjcg07sw2hammhy3jxkarif5i0jszpgk-ipykernel-4.3.1.tar.gz’
cannot build derivation ‘/nix/store/5z2rsbvisv77hqz7rmxlhg1m7kfj7c7y-ihaskell-with-packages.drv’: 1 dependencies couldn't be built
error: build of ‘/nix/store/5z2rsbvisv77hqz7rmxlhg1m7kfj7c7y-ihaskell-with-packages.drv’ failed

Steps to reproduce

nix-build '<nixpkgs>' -A ihaskell

Technical details

• System: 16.09.1512.6b28bd0 (Flounder)
• Nix version: nix-env (Nix) 1.11.6
• Nixpkgs version: 16.09.1512.6b28bd0

[teh]

Thanks for filing an issue! I see you already filed the GHC 8 incompatibility upstream.

You could try the following patch:

diff --git a/pkgs/top-level/all-packages.nix b/pkgs/top-level/all-packages.nix
index 0dc5b81..886a603 100644
--- a/pkgs/top-level/all-packages.nix
+++ b/pkgs/top-level/all-packages.nix
@@ -2253,7 +2253,7 @@ in
 
 
   ihaskell = callPackage ../development/tools/haskell/ihaskell/wrapper.nix {
-    inherit (haskellPackages) ihaskell ghcWithPackages;
+    inherit (haskell.packages.ghc7103) ihaskell ghcWithPackages;
 
     ipython = python3.buildEnv.override {
       extraLibs = with python3Packages; [ ipython ipykernel jupyter_client notebook ];

but it'll require re-building substantial amounts of old code that are no longer being build by hydra. If it works we can apply the patch, otherwise I think I'd vote for removing the package. What do you think?

[vaibhavsagar]

After applying your patch, I'm getting an error building gtk2hs-buildtools (#18586). Is there an easy workaround for this? I'm hopeful that IHaskell will gain GHC 8 compatibility in the near term, so I'd rather not remove the package 😄

[teh]

Reading #18586 I doubt there is.

In order to save other people time maybe we should at least add an assert with an informative message and a link to this bug so other people won't lose time trying to install ihaskell?

[vaibhavsagar]

Sure, that's a good idea.

[teh]

I can't see an easy way of disabling ihaskell, so I suggest removal, followed by re-introduction when fixed. @vaibhavsagar - would you be able to own this?

[vaibhavsagar]

I've created a pull request.

[baracoder]

I am experiencing a similar error on current nixos-unstable channel

nix-env -iA ihaskell -f https://github.com/NixOS/nixpkgs-channels/archive/nixos-unstable.tar.gz 

...

Configuring gtk2hs-buildtools-0.13.4.0...
CallStack (from HasCallStack):
  die', called at libraries/Cabal/Cabal/Distribution/Simple/Configure.hs:950:20 in Cabal-2.4.0.1:Distribution.Simple.Configure
  configureFinalizedPackage, called at libraries/Cabal/Cabal/Distribution/Simple/Configure.hs:460:12 in Cabal-2.4.0.1:Distribution.Simple.Configure
  configure, called at libraries/Cabal/Cabal/Distribution/Simple.hs:596:20 in Cabal-2.4.0.1:Distribution.Simple
  confHook, called at libraries/Cabal/Cabal/Distribution/Simple/UserHooks.hs:67:5 in Cabal-2.4.0.1:Distribution.Simple.UserHooks
  configureAction, called at libraries/Cabal/Cabal/Distribution/Simple.hs:178:19 in Cabal-2.4.0.1:Distribution.Simple
  defaultMainHelper, called at libraries/Cabal/Cabal/Distribution/Simple.hs:115:27 in Cabal-2.4.0.1:Distribution.Simple
  defaultMain, called at Setup.hs:6:8 in main:Main
Setup: Encountered missing dependencies:
base >=4 && <4.12

builder for '/nix/store/4776fq3wwchhb1bnpznxb5fqwbm1zp1g-gtk2hs-buildtools-0.13.4.0.drv' failed with exit code 1