Resolving dependencies...
Starting     yaya-unsafe-test-0.1.1.2
Building     yaya-unsafe-test-0.1.1.2
Failed to install yaya-unsafe-test-0.1.1.2
Build log ( /home/builder/.cabal/logs/ghc-8.6.3/yaya-unsafe-test-0.1.1.2-6ttiwDrbsqB9Df1KbVRxbE.log ):
cabal: Entering directory '/tmp/cabal-tmp-17564/yaya-unsafe-test-0.1.1.2'
Configuring yaya-unsafe-test-0.1.1.2...
Building yaya-unsafe-test-0.1.1.2...
Warning: No documentation was generated as this package does not contain a
library. Perhaps you want to use the --executables, --tests, --benchmarks or
--foreign-libraries flags.
cabal: No executables and no library found. Nothing to do.

cabal: Leaving directory '/tmp/cabal-tmp-17564/yaya-unsafe-test-0.1.1.2'
cabal: Error: some packages failed to install:
yaya-unsafe-test-0.1.1.2-6ttiwDrbsqB9Df1KbVRxbE failed during the final
install step. The exception was:
ExitFailure 1