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panic! no skolem info when using typed template haskell

Summary

When using typed template haskell with equality constraints GHC panics.

Steps to reproduce

{-# LANGUAGE TemplateHaskell #-}
module A where
import Language.Haskell.TH
bomb :: Code Q Int
bomb = [||1||]
{-# LANGUAGE TemplateHaskell #-}
{-# LANGUAGE GADTs #-}
module B where
import A
boom :: (a ~ Int) => a
boom = $$(bomb)

Expected behavior

GHC should not panic.

Environment

  • GHC version used: 9.2.3

Optional:

  • Operating System: NixOS
  • System Architecture: x86_64
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