From: Bulat Ziganshin
try to add performGC at end - this should force collecting garbage and therefore printing of string. otherwise, it's ok - there is no guarantee that GC will be performed and therefore that you finalizer will be performed. it's rather stanard behavior for GC languages - finalizers are almosr useless there
So I changed the code like this but the result was exactly the same. The documentations of both Foreign.ForeignPtr (*1) and Foreign.Concurrent (*2) say "The only guarantee is that the finalizer runs before the program terminates." So I expected the finalizer to be called. import Foreign.Marshal.Alloc import Foreign.Ptr import Foreign.ForeignPtr import System.Mem import qualified Foreign.Concurrent as Conc main = work >> performGC where work = do mem <- mallocBytes 10 Conc.newForeignPtr mem $ print "called" *1: http://haskell.org/ghc/docs/latest/html/libraries/base/Foreign-ForeignPtr.ht... *2: http://haskell.org/ghc/docs/latest/html/libraries/base/Foreign-Concurrent.ht... _______________________________________________________ - PHO - http://ccm.sherry.jp/ OpenPGP public key: 1024D/1A86EF72 Fpr: 5F3E 5B5F 535C CE27 8254 4D1A 14E7 9CA7 1A86 EF72