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sjoerdvisscher/ghcloop.hs

Created October 14, 2010 11:29
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How to make ghc loop.
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ghcloop.hs
{-# LANGUAGE EmptyDataDecls #-}
data Empty
data Loop = CLoop (Loop -> Empty)
loop_step :: Loop -> Empty
loop_step b@(CLoop f) = f b
loop :: Empty
loop = loop_step (CLoop loop_step)
@sjoerdvisscher
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It works fine if you turn Loop into a newtype.

@hesselink
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You don't even need the EmptyDataDecls; changing Empty to () loops as well. Did you file a bug?

@sjoerdvisscher
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Apparently this is a known bug of the inliner. Adding NOINLINE fixes the problem.

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