T17817.hs:16:10: error: [GHC-55287]
    • Unsaturated use of a representation-polymorphic primitive function.
      The first argument of ‘mkWeak#’
      does not have a fixed runtime representation.
      Its type is:
        a :: TYPE ('BoxedRep l)
    • In the expression: mkWeak#
      In an equation for ‘primop’: primop = mkWeak#