testsuite/tests/wasm/should_run/control-flow/src/FailingLint.hs


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{-# LANGUAGE BangPatterns #-}
{-# LANGUAGE MagicHash #-}

module Irr3  -- like Irr, but simplified
where

import GHC.Exts hiding (List)

data List = Nil | Cons !List

length'' :: Int# -> List -> Int#
length'' !trigger !xs =
    case trigger of 0# -> countA 0# xs
                    _  -> countB 0# xs
  where countA !n Nil = n
        countA !n (Cons as) = countB (n +# 1#) as
        countB !n Nil = n
        countB !n (Cons as) = countA (n +# 2#) as
        {-# NOINLINE countA #-}
        {-# NOINLINE countB #-}