4 May
2010
4 May
'10
1:55 a.m.
compiling the following fragment in ghci {-# LANGUAGE StandaloneDeriving #-} import Data.Binary (Binary) newtype Pair a b = Pair (a,b) deriving instance (Binary a, Binary b) => Binary (Pair a b) results in the following message: Prelude> :load "/Users/catbee/Documents/dev/haskell/savestream/foo.hs" [1 of 1] Compiling Main ( /Users/catbee/Documents/dev/haskell/savestream/foo.hs, interpreted ) ghc: panic! (the 'impossible' happened) (GHC version 6.12.1 for i386-apple-darwin): genDerivBinds: bad derived class binary-0.5.0.2:Data.Binary.Binary{tc rkt} Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug should i file a bug report? b