putting left equation sides in parantheses causes GHC.Prim.Any specialization

I put this code into a file:

identity : a -> a
(identity) = id

I get this error message:

Inferred type is less polymorphic than expected
  Quantified type variable `a' escapes
In the expression: id
In a pattern binding: (identity) = id

This may be correct, I don’t know.

However, I can also do this:

(identity) = id

GHCi accepts this. If I enter :type identity into GHCi, I get this:

identity :: GHC.Prim.Any -> GHC.Prim.Any

This seems weird, in my opinion.

This is also accepted by GHCi:

(identity) = id
hello      = identity "hello"

Evaluating hello yields "hello", and :type identity yields this:

identity :: [Char] -> [Char]

Trac metadata

Trac field	Value
Version	6.12.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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