Resolving dependencies...
Configuring html-1.0.1.2...
Configuring mtl-2.2.1...
Building html-1.0.1.2...
Building mtl-2.2.1...
Installed html-1.0.1.2
Configuring network-2.6.3.1...
Configuring tar-0.5.0.3...
Installed mtl-2.2.1
Building tar-0.5.0.3...
Building network-2.6.3.1...
Configuring text-1.2.2.1...
Installed tar-0.5.0.3
Building text-1.2.2.1...
Configuring zlib-0.6.1.2...
Installed network-2.6.3.1
Building zlib-0.6.1.2...
Configuring regex-base-0.93.2...
Installed zlib-0.6.1.2
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
Installed text-1.2.2.1
Configuring parsec-3.1.11...
Building parsec-3.1.11...
Installed parsec-3.1.11
Configuring network-uri-2.6.1.0...
Configuring csv-0.1.2...
Building network-uri-2.6.1.0...
Building csv-0.1.2...
Installed csv-0.1.2
Configuring tabular-0.2.2.7...
Building tabular-0.2.2.7...
Installed network-uri-2.6.1.0
Configuring HTTP-4000.3.4...
Building HTTP-4000.3.4...
Installed tabular-0.2.2.7
Installed HTTP-4000.3.4
Configuring darcs-benchmark-0.1.1...
Failed to install darcs-benchmark-0.1.1
Build log ( /home/builder/.cabal/logs/darcs-benchmark-0.1.1.log ):
cabal: Entering directory '/tmp/cabal-tmp-12517/darcs-benchmark-0.1.1'
cabal: Leaving directory '/tmp/cabal-tmp-12517/darcs-benchmark-0.1.1'
cabal: Error: some packages failed to install:
darcs-benchmark-0.1.1 failed during the configure step. The exception was:
user error ('/opt/ghc/8.0.2/bin/ghc' exited with an error:

/tmp/cabal-tmp-12517/darcs-benchmark-0.1.1/dist/setup/setup.hs:4:1: error:
Failed to load interface for ‘System’
Use -v to see a list of the files searched for.
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