Michael Jones
Sorry I am reviving an old problem, but it has resurfaced, such that one system behaves different than another.
[snip]
1) Does ghc 7.8.4 have any improvements that might pertain to these kinds of scheduling/thread problems? 2) Is there anything about the nature of a thread using USB, I2C, or wxHaskell IO that leads to problems that a pure calculation app would not have?
Do you know about [1]? This is a regression due to an interface change that arose from the new event manager. `usb` 1.3.0.0` has a workaround, GHC 7.10 will have a fixed event manager [2]. Given that it sounds like your program works some of the time this may not be relevant but I thought it would be negligent not to mention it. Cheers, - Ben [1] https://github.com/basvandijk/usb/issues/7 [2] https://phabricator.haskell.org/D347