Hi, you don't say how you processed that example .gc file with GreenCard, but I'm guessing you used the '--target ghc' option. If that's the case, have a look at
http://www.haskell.org/greencard/type-sig.html#SEC-BODY which discusses safe vs. unsafe calls -- i.e., in your case you need to change the %code below to %safecode. (Alternatively, use the -S option). hth --sigbjorn ----- Original Message ----- From: "Chen Yu" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, November 22, 2001 03:42 Subject: greencard bug > Hi, there > I am using Greencard with Hask's foreign function export. I found > the following program can cause seg-fault. Anyone has any idea? BTW, > if I replace greencard with Hask's foreign function import, there > is no such error. > > in ABC.gc: > > foreign export ccall "h_add" h_add :: Int -> IO Int > h_add a = do > putStrLn "in haskell callback" > return (a + 1) > > %fun add :: Int -> IO(Int) > %call (int a) > %code int r; > % r = c_add (a); > %result (int r) > > and the result is like: > > in c callback > in haskell callback > Segmentation Fault > > > > > in add.c: > > _RESULT c_add(int a) { > printf("in c callback\n"); > return h_add(a); > } > > > TIA! > > ------ > chenyu > in Main.hs: > > main = do > a <- add 127 > putStrLn (show a) > _______________________________________________ Glasgow-haskell-bugs mailing list [EMAIL PROTECTED] http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs
