Resolving dependencies...
Configuring monads-tf-0.1.0.3...
Configuring primitive-0.6.1.0...
Building monads-tf-0.1.0.3...
Building primitive-0.6.1.0...
Installed monads-tf-0.1.0.3
Configuring random-1.1...
Building random-1.1...
Installed primitive-0.6.1.0
Configuring vector-0.11.0.0...
Building vector-0.11.0.0...
Installed random-1.1
Configuring tf-random-0.5...
Building tf-random-0.5...
Installed tf-random-0.5
Configuring QuickCheck-2.9.2...
Building QuickCheck-2.9.2...
Installed QuickCheck-2.9.2
Installed vector-0.11.0.0
Configuring x86-64bit-0.1.2...
Building x86-64bit-0.1.2...
Failed to install x86-64bit-0.1.2
Build log ( /home/builder/.cabal/logs/x86-64bit-0.1.2.log ):
cabal: Entering directory '/tmp/cabal-tmp-32056/x86-64bit-0.1.2'
Configuring x86-64bit-0.1.2...
Building x86-64bit-0.1.2...
Preprocessing library x86-64bit-0.1.2...
[1 of 8] Compiling CodeGen.X86.Asm  ( CodeGen/X86/Asm.hs, dist/build/CodeGen/X86/Asm.o )

CodeGen/X86/Asm.hs:269:10: error:
    • Overlapping instances for Monoid (IndexReg s)
        arising from a use of ‘GHC.Base.$dmmconcat’
      Matching instances:
        instance Monoid a => Monoid (Maybe a) -- Defined in ‘GHC.Base’
        instance Monoid (IndexReg s)
          -- Defined at CodeGen/X86/Asm.hs:269:10
    • In the expression: GHC.Base.$dmmconcat @IndexReg s
      In an equation for ‘mconcat’:
          mconcat = GHC.Base.$dmmconcat @IndexReg s
      In the instance declaration for ‘Monoid (IndexReg s)’
cabal: Leaving directory '/tmp/cabal-tmp-32056/x86-64bit-0.1.2'
cabal: Error: some packages failed to install:
x86-64bit-0.1.2 failed during the building phase. The exception was:
ExitFailure 1