Resolving dependencies...
Configuring bmp-1.2.6.3...
Configuring call-stack-0.1.0...
Building bmp-1.2.6.3...
Building call-stack-0.1.0...
Installed call-stack-0.1.0
Configuring heap-1.0.3...
Building heap-1.0.3...
Configuring mtl-2.2.1...
Installed bmp-1.2.6.3
Building mtl-2.2.1...
Configuring parallel-3.2.1.0...
Installed heap-1.0.3
Building parallel-3.2.1.0...
Configuring random-1.1...
Installed parallel-3.2.1.0
Building random-1.1...
Configuring HUnit-1.5.0.0...
Installed mtl-2.2.1
Building HUnit-1.5.0.0...
Installed random-1.1
Configuring mersenne-random-pure64-0.2.2.0...
Building mersenne-random-pure64-0.2.2.0...
Installed HUnit-1.5.0.0
Installed mersenne-random-pure64-0.2.2.0
Downloading crocodile-0.1...
Configuring crocodile-0.1...
Building crocodile-0.1...
Failed to install crocodile-0.1
Build log ( /home/builder/.cabal/logs/crocodile-0.1.log ):
cabal: Entering directory '/tmp/cabal-tmp-32117/crocodile-0.1'
Configuring crocodile-0.1...
Building crocodile-0.1...
Preprocessing executable 'crocodile' for crocodile-0.1...
ghc: unrecognised flag: -fext-core

Usage: For basic information, try the `--help' option.
cabal: Leaving directory '/tmp/cabal-tmp-32117/crocodile-0.1'
cabal: Error: some packages failed to install:
crocodile-0.1 failed during the building phase. The exception was:
ExitFailure 1