#9030: An async exception handler that blocks throwTo until handler finishes running -------------------------------------+------------------------------------ Reporter: jberryman | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: Compiler | Version: 7.8.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: -------------------------------------+------------------------------------ Comment (by ezyang): OK, I looked at your example more carefully, I think this alternate design is more appropriate: you should just mask exceptions before reading from the channel. (Now readChan never services an exception once it has successfully read from the MVar, it will finish processing before admitting the exception.) Mask is exactly about setting up the linearizability properly. This won't help if a blocking call inside the mask requires an exception handler to run, but it feels like this should be rare (i.e. you shouldn't hold onto resources if you're going to block). -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/9030#comment:3 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler