Resolving dependencies...
Configuring darcs-2.3.1...
Failed to install darcs-2.3.1
Build log ( /home/builder/.cabal/logs/darcs-2.3.1.log ):
cabal: Entering directory '/tmp/cabal-tmp-17999/darcs-2.3.1'
cabal: Leaving directory '/tmp/cabal-tmp-17999/darcs-2.3.1'
cabal: Error: some packages failed to install:
darcs-2.3.1 failed during the configure step. The exception was:
user error ('/opt/ghc/8.0.2/bin/ghc' exited with an error:

/tmp/cabal-tmp-17999/darcs-2.3.1/Distribution/ShellHarness.hs:19:1: error:
Failed to load interface for ‘Control.OldException’
Perhaps you meant Control.Exception (from base-4.9.0.0)
Use -v to see a list of the files searched for.
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