[1 of 4] Processing p
  [1 of 2] Compiling H[sig]           ( p/H.hsig, nothing )
  [2 of 2] Compiling M                ( p/M.hs, nothing )
[2 of 4] Processing q
  [1 of 2] Compiling H2[sig]          ( q/H2.hsig, nothing )
  [2 of 2] Compiling N                ( q/N.hs, nothing )
[3 of 4] Processing badimpl
  Instantiating badimpl
  [1 of 1] Compiling H2               ( badimpl/H2.hs, bkpfail22.out/badimpl/H2.o )
[4 of 4] Processing check
  Instantiating check
  [1 of 2] Including q[H2=badimpl:H2]
    Instantiating q[H2=badimpl:H2]
    [1 of 2] Compiling H2[sig]          ( q/H2.hsig, bkpfail22.out/q/q-FjwGsuDQ5qiKUCvnEATUA9/H2.o )

bkpfail22.bkp:16:9: error:
    • Type constructor ‘S’ has conflicting definitions in the module
      and its hsig file
      Main module: type S :: *
                   type S = ()
      Hsig file:  type S :: *
                  type S = GHC.Types.Bool
    • while checking that badimpl:H2 implements signature H2 in q[H2=badimpl:H2]