Strange requirement for re-exported duplicate record fields

In the following example,

module A(A(..)) where
data A = A {x::Int}

module B(B(..)) where
data B = B {x::Bool}

{-# LANGUAGE DuplicateRecordFields #-}
module C(A(..),B(..)) where
import A(A(..))
import B(B(..))

I get an error about conflicting exports for 'x'. This doesn't seem right to me: I've got -XDuplicateRecordFields exactly where the duplicate occurs.

However, I noticed that the if I move the pragma to A.hs, C.hs compiles without error:

{-# LANGUAGE DuplicateRecordFields #-}
module A(A(..)) where
data A = A {x::Int}

module B(B(..)) where
data B = B {x::Bool}

module C(A(..),B(..)) where
import A(A(..))
import B(B(..))

This is bizarre because it is asymmetric (I arbitrarily put the pragma in A.hs, but it need not occur in B.hs), and because no duplicate records exist in module A, but they do exist in module C, where the pragma isn't needed.

Trac metadata

Trac field	Value
Version	8.0.2
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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