Resolving dependencies...
Configuring pcre-light-0.4.0.4...
Configuring mtl-2.2.1...
Building mtl-2.2.1...
Building pcre-light-0.4.0.4...
Installed pcre-light-0.4.0.4
Configuring text-1.2.2.1...
Building text-1.2.2.1...
Installed mtl-2.2.1
Installed text-1.2.2.1
Configuring parsec-3.1.11...
Building parsec-3.1.11...
Installed parsec-3.1.11
Configuring hmk-0.9.7.4...
Building hmk-0.9.7.4...
Failed to install hmk-0.9.7.4
Build log ( /home/builder/.cabal/logs/hmk-0.9.7.4.log ):
cabal: Entering directory '/tmp/cabal-tmp-25677/hmk-0.9.7.4'
Configuring hmk-0.9.7.4...
Building hmk-0.9.7.4...
Preprocessing library hmk-0.9.7.4...
[1 of 5] Compiling Control.Hmk[boot] ( Control/Hmk.lhs-boot, dist/build/Control/Hmk.o-boot )
[2 of 5] Compiling Control.Hmk.Analyze ( Control/Hmk/Analyze.lhs, dist/build/Control/Hmk/Analyze.o )
[3 of 5] Compiling Control.Hmk.Concurrent ( Control/Hmk/Concurrent.lhs, dist/build/Control/Hmk/Concurrent.o )
[4 of 5] Compiling Control.Hmk      ( Control/Hmk.lhs, dist/build/Control/Hmk.o )
[5 of 5] Compiling Control.Hmk.IO   ( Control/Hmk/IO.lhs, dist/build/Control/Hmk/IO.o )
Preprocessing executable 'hmk' for hmk-0.9.7.4...
[1 of 9] Compiling Parse            ( Parse.lhs, dist/build/hmk/hmk-tmp/Parse.o )

Parse.lhs:26:3: warning: [-Wunused-imports]
    The import of ‘Control.Applicative’ is redundant
      except perhaps to import instances from ‘Control.Applicative’
    To import instances alone, use: import Control.Applicative()
[2 of 9] Compiling Control.Hmk[boot] ( Control/Hmk.lhs-boot, dist/build/hmk/hmk-tmp/Control/Hmk.o-boot )
[3 of 9] Compiling Control.Hmk.Analyze ( Control/Hmk/Analyze.lhs, dist/build/hmk/hmk-tmp/Control/Hmk/Analyze.o )
[4 of 9] Compiling Control.Hmk.Concurrent ( Control/Hmk/Concurrent.lhs, dist/build/hmk/hmk-tmp/Control/Hmk/Concurrent.o )

Control/Hmk/Concurrent.lhs:20:3: warning: [-Wunused-imports]
    The import of ‘Control.Applicative’ is redundant
      except perhaps to import instances from ‘Control.Applicative’
    To import instances alone, use: import Control.Applicative()
[5 of 9] Compiling Control.Hmk      ( Control/Hmk.lhs, dist/build/hmk/hmk-tmp/Control/Hmk.o )
[6 of 9] Compiling Control.Hmk.IO   ( Control/Hmk/IO.lhs, dist/build/hmk/hmk-tmp/Control/Hmk/IO.o )
[7 of 9] Compiling Eval             ( Eval.lhs, dist/build/hmk/hmk-tmp/Eval.o )

Eval.lhs:146:65: error:
    • Ambiguous type variable ‘m0’ arising from a use of ‘eval'’
      prevents the constraint ‘(Foldable m0)’ from being solved.
      Relevant bindings include
        virtuals :: m0 [Char] (bound at Eval.lhs:146:40)
      Probable fix: use a type annotation to specify what ‘m0’ should be.
      These potential instances exist:
        instance Foldable ZipList -- Defined in ‘Control.Applicative’
        instance Foldable (Either a) -- Defined in ‘Data.Foldable’
        instance Foldable Dual -- Defined in ‘Data.Foldable’
        ...plus 13 others
        ...plus 29 instances involving out-of-scope types
        (use -fprint-potential-instances to see them all)
    • In the first argument of ‘runWriterT’, namely
        ‘(eval' virtuals mkfile)’
      In a stmt of an 'mdo' block:
        (rules, RevAppend virtuals) <- runWriterT (eval' virtuals mkfile)
      In a stmt of an 'mdo' block:
        rec { (rules, RevAppend virtuals) <- runWriterT
                                               (eval' virtuals mkfile) }
cabal: Leaving directory '/tmp/cabal-tmp-25677/hmk-0.9.7.4'
cabal: Error: some packages failed to install:
hmk-0.9.7.4 failed during the building phase. The exception was:
ExitFailure 1