Fails to build with ghc-7.8

[leonbaum]

src/Network/Remote/RPC/Internal/Runtime.hs:158:10:
    Illegal instance declaration for
      `Receivable m (a -> b) m' (a' -> WIO w' m' b')'
      The liberal coverage condition fails in class `Receivable'
        for functional dependency: m' a -> a'
      Reason: lhs types m', `a -> b'
        do not jointly determine rhs type a' -> WIO w' m' b'
    In the instance declaration for
      `Receivable m (a -> b) m' (a' -> WIO w' m' b')'

[donatello]

:+1: Happens to me too.

[mmirman]

Yeah, I was kinda relying on a bug in an older version of ghc that failed to do the coverage check for functional dependencies in the presence of overlapping instances. I'm actively searching for another work around.