Resolving dependencies... Starting validity-0.12.0.0 Starting splitmix-0.1.0.4 Building validity-0.12.0.0 Building splitmix-0.1.0.4 Completed validity-0.12.0.0 Starting validity-time-0.4.0.0 Completed splitmix-0.1.0.4 Starting random-1.2.1 Building validity-time-0.4.0.0 Building random-1.2.1 Completed validity-time-0.4.0.0 Completed random-1.2.1 Starting QuickCheck-2.14.2 Building QuickCheck-2.14.2 Completed QuickCheck-2.14.2 Starting genvalidity-1.0.0.0 Building genvalidity-1.0.0.0 Completed genvalidity-1.0.0.0 Starting genvalidity-time-1.0.0.0 Building genvalidity-time-1.0.0.0 Failed to install genvalidity-time-1.0.0.0 Build log ( /home/builder/.cabal/logs/ghc-8.10.2/genvalidity-time-1.0.0.0-2mv1SvRiA123tcScSVxEXQ.log ): cabal: Entering directory '/tmp/cabal-tmp-32713/genvalidity-time-1.0.0.0' Configuring genvalidity-time-1.0.0.0... Preprocessing library for genvalidity-time-1.0.0.0.. Building library for genvalidity-time-1.0.0.0.. [1 of 6] Compiling Data.GenValidity.Time.Calendar ( src/Data/GenValidity/Time/Calendar.hs, dist/build/Data/GenValidity/Time/Calendar.o, dist/build/Data/GenValidity/Time/Calendar.dyn_o ) src/Data/GenValidity/Time/Calendar.hs:38:10: error: " No instance for (Validity CalendarDiffDays) arising from the superclasses of an instance declaration " In the instance declaration for GenValid CalendarDiffDays | 38 | instance GenValid CalendarDiffDays where | ^^^^^^^^^^^^^^^^^^^^^^^^^ src/Data/GenValidity/Time/Calendar.hs:42:10: error: " No instance for (Validity DayOfWeek) arising from the superclasses of an instance declaration " In the instance declaration for GenValid DayOfWeek | 42 | instance GenValid DayOfWeek where | ^^^^^^^^^^^^^^^^^^ cabal: Leaving directory '/tmp/cabal-tmp-32713/genvalidity-time-1.0.0.0' cabal: Error: some packages failed to install: genvalidity-time-1.0.0.0-2mv1SvRiA123tcScSVxEXQ failed during the building phase. The exception was: ExitFailure 1