Hello, I want to build jhc 0.82 on debian/amd64. I downloaded the sources and successfully configured the build. The compilation fails with this error: [149 of 186] Compiling Ho.Binary ( src/Ho/Binary.hs, src/Ho/Binary.o ) src/Ho/Binary.hs:164:10: Duplicate instance declarations: instance [overlap ok] Binary Data.Version.Version -- Defined at src/Ho/Binary.hs:164:10 instance [safe] Binary Data.Version.Version -- Defined in `binary-0.8.0.0:Data.Binary.Class' Makefile:1441: recipe for target 'jhc' failed The corresponding source code in src/Ho/Binary.hs is: import Data.Binary import qualified Data.Version instance Binary Data.Version.Version where put (Data.Version.Version a b) = put a >> put b get = liftM2 Data.Version.Version get get In the package binary, is this error due to this line ? import Data.Version (Version(..)) Any hint to solve this ? -- Fabien