Configuring nettle-0.1.0...
Flags chosen: usepkgconfig=True
Dependency base ==4.6.0.1: using base-4.6.0.1
Dependency byteable ==0.1.1: using byteable-0.1.1
Dependency bytestring ==0.10.0.2: using bytestring-0.10.0.2
Dependency crypto-cipher-types ==0.0.7: using crypto-cipher-types-0.0.7
Dependency securemem ==0.1.3: using securemem-0.1.3
Dependency tagged ==0.7: using tagged-0.7
setup-Cabal-1.16.0.3-ghc-7.6.3: The program pkg-config version >=0.9.0 is
required but it could not be found.