If GHC <= 7.2 isn't supported anymore, please constraint to base>=4.5 in future releases
The error is
Configuring lifted-async-0.6.0...
Building lifted-async-0.6.0...
Preprocessing library lifted-async-0.6.0...
src/Control/Concurrent/Async/Lifted/Safe.hs:1:14:
Unsupported extension: ConstraintKinds
Failed to install lifted-async-0.6.0
cabal: Error: some packages failed to install:
lifted-async-0.6.0 failed during the building phase. The exception was:
ExitFailure 1
If GHC <= 7.2 isn't supported anymore, please constraint to
base>=4.5
in future releasesThe error is