#13130: atomicModifyMutVar# has incorrect type -------------------------------------+------------------------------------- Reporter: carter | Owner: Type: bug | Status: new Priority: normal | Milestone: 8.2.1 Component: Compiler | Version: 8.0.1 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- this ticket specifically, currently we only expose in ghc-prim {{{ atomicModifyMutVar# :: MutVar# s a -> (a -> b) -> State# s -> (# State# s,c #) }}} is the type more like the following? {{{ atomicModifyMutVar# :: MutVar# s a -> (a -> (#a,b #)) -> State# s -> (# State# s,b #) }}} looking at GHC.IOREF {{{ atomicModifyIORef :: IORef a -> (a -> (a,b)) -> IO b atomicModifyIORef (IORef (STRef r#)) f = IO $ \s -> atomicModifyMutVar# r# f s }}} it seems that either way, something screwy is afoot i'm not sure where the spurious c type variable comes from -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/13130 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler