Hi, I am preparing a talk about the details of how data and programs look in memory in Haskell (well, GHC). When explaining the memory consumption of a large String, I wanted to show the effect of short-int-replacement that happens in http://hackage.haskell.org/trac/ghc/browser/rts/sm/Evac.c#L550 I use my ghc-heap-view-package to observe the heap. This programs shows the effect: import GHC.HeapView import System.Mem main = do let hallo = "hallo" mapM_ (\x -> putStrLn $ show x ++ ": " ++ show (asBox x)) hallo performGC mapM_ (\x -> putStrLn $ show x ++ ": " ++ show (asBox x)) hallo gives, as expected: $ ./SmallChar 'h': 0x00007f2811e042a8/1 'a': 0x00007f2811e08128/1 'l': 0x00007f2811e09ef0/1 'l': 0x00007f2811e0bcd8/1 'o': 0x00007f2811e0db10/1 'h': 0x00000000006d9bd0/1 'a': 0x00000000006d9b60/1 'l': 0x00000000006d9c10/1 'l': 0x00000000006d9c10/1 'o': 0x00000000006d9c40/1 but in GHCi, it does not work: $ runhaskell SmallChar.hs 'h': 0x00007f5334623d58/1 'a': 0x00007f5334626208/1 'l': 0x00007f5334627fc0/1 'l': 0x00007f5334629dc0/1 'o': 0x00007f533462bba8/1 'h': 0x00007f533381a1c8/1 'a': 0x00007f5333672e30/1 'l': 0x00007f533381a408/1 'l': 0x00007f533381a6b8/1 'o': 0x00007f533389c5d0/1 Note that the GC does evacuate the closures, as the pointers change. Why are these not replaced by the static ones here? Thanks, Joachim -- Joachim "nomeata" Breitner mail@joachim-breitner.de | nomeata@debian.org | GPG: 0x4743206C xmpp: nomeata@joachim-breitner.de | http://www.joachim-breitner.de/