#7787: modifyMVar does not restore value if callback returns error value ----------------------------------------+----------------------------------- Reporter: joeyadams | Owner: Type: bug | Status: new Priority: normal | Component: libraries/base Version: 7.7 | Keywords: Os: Unknown/Multiple | Architecture: Unknown/Multiple Failure: Incorrect result at runtime | Blockedby: Blocking: | Related: ----------------------------------------+----------------------------------- Comment(by ezyang): Another possibility is to replace the pattern match with an irrefutable pattern. I'm not sure which is better, though an irrefutable pattern could make laziness bugs worse. -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/7787#comment:1 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler