Resolving dependencies...
Configuring mtl-2.2.1...
Configuring extensible-exceptions-0.1.1.4...
Building mtl-2.2.1...
Building extensible-exceptions-0.1.1.4...
Installed extensible-exceptions-0.1.1.4
Installed mtl-2.2.1
Configuring regex-base-0.93.2...
Building regex-base-0.93.2...
Installed regex-base-0.93.2
Configuring regex-posix-0.95.2...
Building regex-posix-0.95.2...
Installed regex-posix-0.95.2
Configuring regex-compat-0.95.1...
Building regex-compat-0.95.1...
Installed regex-compat-0.95.1
Configuring encoding-0.6.0...
Failed to install encoding-0.6.0
Build log ( /home/builder/.cabal/logs/encoding-0.6.0.log ):
cabal: Entering directory '/tmp/cabal-tmp-15320/encoding-0.6.0'
cabal: Leaving directory '/tmp/cabal-tmp-15320/encoding-0.6.0'
cabal: Error: some packages failed to install:
encoding-0.6.0 failed during the configure step. The exception was:
user error ('/opt/ghc/8.0.2/bin/ghc' exited with an error:

/tmp/cabal-tmp-15320/encoding-0.6.0/Data/Encoding/Preprocessor/XMLMapping.hs:9:1:
error:
Failed to load interface for ‘Text.XML.HaXml.XmlContent’
Use -v to see a list of the files searched for.

/tmp/cabal-tmp-15320/encoding-0.6.0/Data/Encoding/Preprocessor/XMLMapping.hs:10:1:
error:
Failed to load interface for ‘Text.XML.HaXml.OneOfN’
Use -v to see a list of the files searched for.
)