Re: BlockedIndefinitelyOnMVar exception

2010-07-04 Thread Neil Mitchell
Hi Simon, My suspicion for the root cause of the problem is that Concurrent.Chan is incorrect. In the course of debugging this problem we found 2 bugs in Chan, and while I never tracked down any other bugs in Chan, I no longer trust it. By rewriting parts of the program, including avoiding

Re: BlockedIndefinitelyOnMVar exception

2010-07-04 Thread Simon Marlow
On 04/07/10 10:30, Neil Mitchell wrote: Hi Simon, My suspicion for the root cause of the problem is that Concurrent.Chan is incorrect. In the course of debugging this problem we found 2 bugs in Chan, and while I never tracked down any other bugs in Chan, I no longer trust it. By rewriting

Re: BlockedIndefinitelyOnMVar exception

2010-07-04 Thread Neil Mitchell
http://hackage.haskell.org/trac/ghc/ticket/4154 Yup, that's a bug.  Not clear if it's fixable. http://hackage.haskell.org/trac/ghc/ticket/3527 That too.  A very similar bug in fact, if there is a fix it will probably fix both of them.  The problem is that readChan holds a lock on the read