examples/factorial let/app issues in HERMIT

Fac.hs

{-# LANGUAGE MagicHash #-}
{-# LANGUAGE CPP #-}

module Main where

import Prelude hiding ((*),(-))
import GHC.Exts

------------------------------------

fac :: Int -> Int
fac 0 = 1
fac n = n * fac (n -1)

unwrap :: (Int -> Int) -> Int# -> Int#
unwrap h x = case h (I# x) of
               I# y -> y

wrap :: (Int# -> Int#) -> Int -> Int
wrap h (I# x) = I# (h x)

main :: IO ()
main = print (fac 10)


(*) :: Int -> Int -> Int
(I# x) * (I# y) = I# (x *# y)

(-) :: Int -> Int -> Int
(I# x) - (I# y) = I# (x -# y)

------------------------------------

Fac.hss

set-auto-corelint True
load-as-rewrite "WWA" "WW-Ass-A.hss"
flatten-module
binding-of 'fac
ww-split [| wrap |] [| unwrap |] (ww-AssA-to-AssC WWA)
bash-extended-with [ case-elim-inline-scrutinee , inline [ 'unwrap, 'wrap, '*, '- ] ]

{ [def-rhs, let-body] ; alpha-lam 'n } -- cosmetic

output-with-bad-code.txt

*** Core Lint errors : in result of Core plugin:  HERMIT0 ***
<no location info>: Warning:
    In the expression: *# x_a1J6 (work_s2zJ (-# x_a1J6 1))
    This argument does not satisfy the let/app invariant:
      work_s2zJ (-# x_a1J6 1)
*** Offending Program ***
Rec {
* :: Int -> Int -> Int
[LclIdX, Str=DmdType]
* =
  \ (ds_d2z5 [Occ=Once!] :: Int) (ds_d2z6 [Occ=Once!] :: Int) ->
    case ds_d2z5 of _ [Occ=Dead] { I# x_a1MI [Occ=Once] ->
    case ds_d2z6 of _ [Occ=Dead] { I# y_a1MJ [Occ=Once] ->
    I# (*# x_a1MI y_a1MJ)
    }
    }

- :: Int -> Int -> Int
[LclIdX, Str=DmdType]
- =
  \ (ds_d2z3 [Occ=Once!] :: Int) (ds_d2z4 [Occ=Once!] :: Int) ->
    case ds_d2z3 of _ [Occ=Dead] { I# x_a1MK [Occ=Once] ->
    case ds_d2z4 of _ [Occ=Dead] { I# y_a1ML [Occ=Once] ->
    I# (-# x_a1MK y_a1ML)
    }
    }

fac [Occ=LoopBreaker] :: Int -> Int
[LclIdX, Str=DmdType]
fac =
  letrec {
    work_s2zJ [Occ=LoopBreaker] :: Int# -> Int#
    [LclId, Str=DmdType]
    work_s2zJ =
      \ (x_a1J6 :: Int#) ->
        case x_a1J6 of _ [Occ=Dead] {
          __DEFAULT -> *# x_a1J6 (work_s2zJ (-# x_a1J6 1));   -- *** I think the error is here ***
          0 -> 1
        }; } in
  \ (ds_d2z7 [Occ=Once!] :: Int) ->
    case ds_d2z7 of _ [Occ=Dead] { I# x_a1J9 [Occ=Once] ->
    I# (work_s2zJ x_a1J9)
    }

unwrap :: (Int -> Int) -> Int# -> Int#
[LclIdX, Str=DmdType]
unwrap =
  \ (h_a1J5 [Occ=Once!] :: Int -> Int) (x_a1J6 [Occ=Once] :: Int#) ->
    case h_a1J5 (I# x_a1J6) of _ [Occ=Dead] { I# y_a1J7 [Occ=Once] ->
    y_a1J7
    }

wrap :: (Int# -> Int#) -> Int -> Int
[LclIdX, Str=DmdType]
wrap =
  \ (h_a1J8 [Occ=Once!] :: Int# -> Int#)
    (ds_d2z7 [Occ=Once!] :: Int) ->
    case ds_d2z7 of _ [Occ=Dead] { I# x_a1J9 [Occ=Once] ->
    case h_a1J8 x_a1J9 of wild_X9 { __DEFAULT -> I# wild_X9 }
    }

main :: IO ()
[LclIdX, Str=DmdType]
main = print @ Int $fShowInt (fac (I# 10))

main :: IO ()
[LclIdX, Str=DmdType]
main = runMainIO @ () main
end Rec }

*** End of Offense ***


<no location info>: 
Compilation had errors

output.txt

Error in expression: bash-extended-with [case-elim-inline-scrutinee,inline ['unwrap,'wrap,'*,'-]]
Core Lint Failed:
<no location info>: Warning:
    In the expression: *# x (work_s2zJ (-# x 1))
    This argument does not satisfy the let/app invariant:
      work_s2zJ (-# x 1)

fac = (let {
  f_s2zu :: (Int -> Int) -> Int -> Int
  [LclId, Str=DmdType]
  f_s2zu =
    \ (fac_s2zk :: Int -> Int) (ds_d2z9 :: Int) ->
      case ds_d2z9 of _ [Occ=Dead] { I# ds_d2za ->
      case ds_d2za of _ [Occ=Dead] {
        __DEFAULT ->
          (\ _ [Occ=Dead, OS=OneShot] ->
             * ds_d2z9 (fac_s2zk (- ds_d2z9 (I# 1))))
            void#;
        0 -> I# 1
      }
      } } in
letrec {
  work_s2zJ :: Int# -> Int#
  [LclId, Str=DmdType]
  work_s2zJ = unwrap (f_s2zu (wrap work_s2zJ)); } in
wrap work_s2zJ)