Signature generation roundtrip issue: overloaded member with unit parameter

[T-Gro]

Implementation:

module Repro
type R1 = { f1 : int }
type R2 = { f2 : int }
type D() =
    member x.N = x.M { f1 = 3 }
    member x.M((y: R1)) = ()
    member x.M(()) = ()

Actual generated signature:

module Repro

type R1 = { f1: int }
type R2 = { f2: int }
type D =
    new: unit -> D
    member M: unit -> unit
    member M: y: R1 -> unit
    member N: unit

Error on roundtrip compile:

error FS0193: Module requires a value 'member D.M: unit -> unit'

The generated member M: unit -> unit cannot be matched with member x.M(()) = ().

Expected signature:

[<Class>]
type D =
    new: unit -> D
    member M: y: R1 -> unit
    member M: unit -> unit
    member N: unit

Verified: roundtrips successfully (same content, just added [<Class>]).