System.Posix.Semaphore shouldn't create finalizers with Foreign.newForeignPtr

[kaol]

Running this program

import System.Posix.Semaphore

main = do
        s <- semOpen "c" (OpenSemFlags True False) 0666 1
        semThreadWait s
        v <- semGetValue s
        putStrLn "Type!"
        a <- getLine
        putStrLn $ "OK, " ++ a
        semPost s

fails like this:

Type!
abc
OK, abc
sem: error: a C finalizer called back into Haskell.
This was previously allowed, but is disallowed in GHC 6.10.2 and later.
To create finalizers that may call back into Haskll, use
Foreign.Concurrent.newForeignPtr instead of Foreign.newForeignPtr.

The attached patch for libraries/unix/System/Posix/Semaphore.hsc should fix this.

[simonmar]

I'll validate and push; thanks.

[simonmar]

Applied

Tue Sep  8 07:25:36 PDT 2009  Simon Marlow <marlowsd@gmail.com>
  * Use Foreign.Concurrent for Haskell finalizers (#3473)