nix-env -iA nixpkgs.haskellPackages.ghc-mod
installing 'ghc-mod-5.8.0.0'
these derivations will be built:
  /nix/store/2a2jj73557yn9wr4mfj2gjfdg4qsx96x-ghc-mod-5.8.0.0.drv
building '/nix/store/2a2jj73557yn9wr4mfj2gjfdg4qsx96x-ghc-mod-5.8.0.0.drv'...
setupCompilerEnvironmentPhase
Build with /nix/store/70bs1dmdv2m2vxbd38hd5d50lf6d4apm-ghc-8.2.2.
unpacking sources
unpacking source archive /nix/store/vq4zl3c2hhn78vqqpqsdp1466wl1iniq-ghc-mod-5.8.0.0.tar.gz
source root is ghc-mod-5.8.0.0
setting SOURCE_DATE_EPOCH to timestamp 1495938286 of file ghc-mod-5.8.0.0/test/TestUtils.hs
patching sources
Replace Cabal file with edited version from http://hackage.haskell.org/package/ghc-mod-5.8.0.0/revision/1.cabal.
compileBuildDriverPhase
setupCompileFlags: -package-db=/tmp/nix-build-ghc-mod-5.8.0.0.drv-0/package.conf.d -j1 -threaded
[1 of 1] Compiling Main             ( Setup.hs, /tmp/nix-build-ghc-mod-5.8.0.0.drv-0/Main.o )

Setup.hs:85:60: error:
    • Couldn't match expected type ‘UnitId’
                  with actual type ‘PathTemplate’
    • In the third argument of ‘substPathTemplate’, namely
        ‘(progPrefix lbi)’
      In the expression:
        substPathTemplate (packageId pd) lbi (progPrefix lbi)
      In an equation for ‘progprefix’:
          progprefix = substPathTemplate (packageId pd) lbi (progPrefix lbi)
   |
85 |         progprefix = substPathTemplate (packageId pd) lbi (progPrefix lbi)
   |                                                            ^^^^^^^^^^^^^^

Setup.hs:86:60: error:
    • Couldn't match expected type ‘UnitId’
                  with actual type ‘PathTemplate’
    • In the third argument of ‘substPathTemplate’, namely
        ‘(progSuffix lbi)’
      In the expression:
        substPathTemplate (packageId pd) lbi (progSuffix lbi)
      In an equation for ‘progsuffix’:
          progsuffix = substPathTemplate (packageId pd) lbi (progSuffix lbi)
   |
86 |         progsuffix = substPathTemplate (packageId pd) lbi (progSuffix lbi)
   |                                                            ^^^^^^^^^^^^^^

Setup.hs:87:28: error:
    • Couldn't match expected type ‘[a]’
                  with actual type ‘PathTemplate -> FilePath’
    • Probable cause: ‘progprefix’ is applied to too few arguments
      In the first argument of ‘(++)’, namely ‘progprefix’
      In the expression: progprefix ++ exeName exe ++ progsuffix
      In an equation for ‘fixedExeBaseName’:
          fixedExeBaseName = progprefix ++ exeName exe ++ progsuffix
    • Relevant bindings include
        fixedExeBaseName :: [a] (bound at Setup.hs:87:9)
   |
87 |         fixedExeBaseName = progprefix ++ exeName exe ++ progsuffix
   |                            ^^^^^^^^^^

Setup.hs:87:42: error:
    • Couldn't match expected type ‘[a]’
                  with actual type ‘Distribution.Types.UnqualComponentName.UnqualComponentName’
    • In the first argument of ‘(++)’, namely ‘exeName exe’
      In the second argument of ‘(++)’, namely
        ‘exeName exe ++ progsuffix’
      In the expression: progprefix ++ exeName exe ++ progsuffix
    • Relevant bindings include
        fixedExeBaseName :: [a] (bound at Setup.hs:87:9)
   |
87 |         fixedExeBaseName = progprefix ++ exeName exe ++ progsuffix
   |                                          ^^^^^^^^^^^

Setup.hs:87:57: error:
    • Couldn't match expected type ‘[a]’
                  with actual type ‘PathTemplate -> FilePath’
    • Probable cause: ‘progsuffix’ is applied to too few arguments
      In the second argument of ‘(++)’, namely ‘progsuffix’
      In the second argument of ‘(++)’, namely
        ‘exeName exe ++ progsuffix’
      In the expression: progprefix ++ exeName exe ++ progsuffix
    • Relevant bindings include
        fixedExeBaseName :: [a] (bound at Setup.hs:87:9)
   |
87 |         fixedExeBaseName = progprefix ++ exeName exe ++ progsuffix
   |                                                         ^^^^^^^^^^

Setup.hs:92:26: error:
    • Couldn't match expected type ‘Distribution.Types.UnqualComponentName.UnqualComponentName’
                  with actual type ‘[Char]’
    • In the second argument of ‘(==)’, namely ‘"ghc-mod-real"’
      In the first argument of ‘when’, namely
        ‘(exeName exe == "ghc-mod-real")’
      In the expression: when (exeName exe == "ghc-mod-real")
   |
92 |     when (exeName exe == "ghc-mod-real") $ do
   |                          ^^^^^^^^^^^^^^
builder for '/nix/store/2a2jj73557yn9wr4mfj2gjfdg4qsx96x-ghc-mod-5.8.0.0.drv' failed with exit code 1
error: build of '/nix/store/2a2jj73557yn9wr4mfj2gjfdg4qsx96x-ghc-mod-5.8.0.0.drv' failed