Core Lint error with a data type

The following data declaration fails -dcore-lint

{-# LANGUAGE PolyKinds, ExplicitForAll, ExistentialQuantification #-}

module T16221 where
data T0 a = forall k (b :: k). MkT0 (T0 b) !Int

The test case was extracted from T14066a, the bang is to force the data type to have a wrapper. This has been present at least since GHC 8.0.

<no location info>: warning:
    In the type ‘T0 a_a1wY’
    Kind application error in type ‘T0 a_a1wY’
      Function kind = forall k. k -> *
      Arg kinds = [(k_X1x2, *), (a_a1wY, k_a1wZ)]
    Fun: k_X1x2
         (a_a1wY, k_a1wZ)
<no location info>: warning:
    In the expression: MkT0
                         @ k_X1x2 @ a_a1wY @ k_X1x2 @ b_a1x0 dt_a1xC dt_X1xK
    Kinds don't match in type application:
    Type variable: a_X1xw :: k_X1x2
    Arg type: a_a1wY :: k_a1wZ
    Linted Arg kind: k_a1wZ
<no location info>: warning:
    In the type ‘T0 a_a1wY’
    Kind application error in type ‘T0 a_a1wY’
      Function kind = forall k. k -> *
      Arg kinds = [(k_X1x2, *), (a_a1wY, k_a1wZ)]
    Fun: k_X1x2
         (a_a1wY, k_a1wZ)
<no location info>: warning:
    In the expression: MkT0
                         @ k_X1x2 @ a_a1wY @ k_X1x2 @ b_a1x0 dt_a1xC dt_X1xK
    Kinds don't match in type application:
    Type variable: a_X1xw :: k_X1x2
    Arg type: a_a1wY :: k_a1wZ
    Linted Arg kind: k_a1wZ

Trac metadata

Trac field	Value
Version	8.7
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler (Type checker)
Test case
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