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Compiling this code:

{-# LANGUAGE Strict #-}

data Lazy a = Lazy ~a

main :: IO ()
main = case Lazy undefined of
            Lazy _ -> putStrLn "Lazy"

fails with the following error:

$ .\inplace\bin\ghc-stage2.exe ../Lazy.hs
[1 of 1] Compiling Main             ( ..\Lazy.hs, ..\Lazy.o )

..\Lazy.hs:3:15: error:
    * Lazy annotation (~) without StrictData
        on the first argument of `Lazy'
    * In the definition of data constructor `Lazy'
      In the data type declaration for `Lazy'

I was under the impression that -XStrict implied -XStrictData. Is this not the case?

Trac metadata

Trac field	Value
Version	7.11
Type	Bug
TypeOfFailure	OtherFailure
Priority	normal
Resolution	Unresolved
Component	Compiler
Test case
Differential revisions
BlockedBy
Related
Blocking
CC	adamse, osa1, tibbe
Operating system
Architecture