Fix a potential space leak related to HasCallStack quirks #279
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The following program: ```haskell import Control.Monad import Effectful import Effectful.Concurrent import Effectful.Concurrent.MVar import Effectful.Reader.Dynamic import Effectful.Provider import Effectful.Provider.List f :: Concurrent :> es => MVar () -> Int -> Eff es () f var = \case 0 -> putMVar var () n -> void $ forkIO $ f var (n - 1) main :: IO () main = runEff . runReader () . runProvider_ (\() -> runReader ()) . runProviderList_ @'[Reader ()] (\() -> runReader ()) . runConcurrent $ do var <- newEmptyMVar f var 10000000 takeMVar var ``` used to leak memory because GHC attaches a new stack frame to fields with HasCallStack constraints on every record reconstruction. Here it means every relinking, so if the relinks are nested, call stacks atached to these fields will keep growing. The workaround is to wrap these fields in newtypes, see https://gitlab.haskell.org/ghc/ghc/-/issues/25520 for more information.
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The following program:
used to leak memory because GHC attaches a new stack frame to fields with HasCallStack constraints on every record reconstruction. Here it means every relinking, so if the relinks are nested, call stacks atached to these fields will keep growing.
The workaround is to wrap these fields in newtypes, see https://gitlab.haskell.org/ghc/ghc/-/issues/25520 for more information.