Inline and Noinline pragmas ignored for instance functions

An example source file which triggers the incorrect behaviour follows. I am currently unclear whether the effected inline and noinline pragmas are actually ignored by the simplifier or whether the inline rule shadowing warning is fired incorrectly.

class A a where
  (>>#) :: a -> a -> a

instance A (Maybe a) where
  {-# NOINLINE (>>#) #-}
  a >># b = undefined

{-# RULES
"example" forall (a :: Maybe Int) (b :: Maybe Int) . a >># b = Just 4
 #-}

Trac metadata

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