Backticks in an an error message

{-# LANGUAGE TypeOperators #-}
data X a b

f :: (a `X` a, Maybe)
f = undefined

gives an error message:

X.hs:4:16:
    Expecting one more argument to `Maybe'
    In the type signature for `f': f :: (a X a, Maybe)
                                         ^^^^^

which should be a X a. The same thing happens in constraints, such as

f :: (a `X` a) => Maybe

Trac metadata

Trac field	Value
Version	7.6.1
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
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