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Segmentation fault with UnliftedDatatypes in GHCi

I got a segfault while loading a file with unlifted data types into GHCi. I created this file:

-- Unlifted.hs
{-# LANGUAGE UnliftedDatatypes #-}

import GHC.Exts

type Strict :: * -> TYPE ('BoxedRep 'Unlifted)
data Strict a = Force a

x :: Int
x = 10
  where
    test :: Strict Int
    test = Force undefined

Then I loaded it in GHCi and tried evaluating x:

$ ghci Unlifted.hs
... (some warnings about the * kind and the unused test variable)
> x
Segmentation fault

Environment

  • GHC version used: 9.2.0.20210331

Optional:

  • Operating System: Debian 10
  • System Architecture: Linux x86_64
Edited by Jaro Reinders
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