Re:GHC 7 is out: Haskell 2010 support; LLVM backend; new opt...
by pufuwozu on Tuesday November 16, 2010 @12:01AM
(#1909111)
The Windows operating system presents a difficulty to our current design. Its support for scalable event notification is based around I/O completion ports, which are integrated tightly with the Windows threading mechanism, and which would require a considerable amount of replumbing to support.
From http://www.serpentine.com/bos/files/ghc-event-manager.pdf