Missing context in Generics example

The Haddocks for GHC.Generics give an example of a default implementation using Generics:

class Encode a where
  encode :: a -> [Bool]
  default encode :: (Generic a) => a -> [Bool]
  encode x = encode' (from x)

The default signature is missing some context. It should read

  default encode :: (Generic a, Encode' (Rep a)) => a -> [Bool]

Trac metadata

Trac field	Value
Version	7.10.3
Type	Bug
TypeOfFailure	OtherFailure
Priority	high
Resolution	Unresolved
Component	Core Libraries
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CC	ekmett
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