Haddock documentation for pattern synonyms printed with explicit forall quantifiers

Running haddock on:

{-# LANGUAGE PatternSynonyms #-}

module Foo ( A(..), pattern P ) where

data A a = A a

pattern P :: a -> A a
pattern P a <- A a

in GHC 7.10.3 gives haddock documentation for P in the form of:

pattern P :: a -> A a

while the haddock in GHC 8.0.1-rc3 gives haddock documentation for P in the form of:

pattern P :: forall a. a -> A a

I think GHC/Haddock should not be adding the forall quantifier, and hence think the behaviour in GHC 8.0.1-rc3 is wrong, and the behaviour of GHC 7.10.3 is preferred.

Trac metadata

Trac field	Value
Version	8.0.1-rc3
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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