FunPtr callbacks broken?

[Wolfgang Thaller]

> simplejack: schedule: re-entered unsafely.
>    Perhaps a 'foreign import unsafe' should be 'safe'?
>
> Am I misusing something? Or is this a compiler bug? Google indicated
> that the last time someone had this problem it was a compiler bug...
>
> Here is the test program. It requires jack to be running
> (http://jackit.sf.net) and I built it with:
>
> ghc --make -fglasgow-exts SimpleJack.hs -o simplejack  -ljack

Are jack callbacks invoked on a second thread? (looks like they are).  
If so, you need to use the threaded RTS, activated by passing - 
threaded to ghc.

ghc --make -fglasgow-exts SimpleJack.hs -o simplejack  -ljack -threaded

Cheers,

Wolfgang