Re: [Haskell-cafe] Logging pure code

On Mon, Jul 30, 2012 at 1:54 AM, Thomas Schilling wrote:

On 27 July 2012 14:52, Marco Túlio Gontijo e Silva wrote:

...

thread blocked indefinitely in an MVar operation

IIRC, that means that a thread is blocked on an MVar and the MVar is only reachable by that thread.

This sounds right. STM has noticed that there's a thread waiting for something that will never be available. It seems it have found a deadlock. I once tried mixing IO and STM actions (IO inside STM) and ended up rewriting the code to seperate the two. Before the rewrite, I got some of the strangest and most unpredictable errors I've ever seen in a Haskell program. I reckon this could be related. Here's the thread from back then: http://www.haskell.org/pipermail/haskell-cafe/2012-January/098453.html -- Johan Brinch