randomplay: internal error: scavenge_stack: weird activation record found on stack: 0 Please report this as a bug to glasgow-haskell-bugs@haskell.org, or http://www.sourceforge.net/projects/ghc/ I installed my own signal handlers with the intent of having my profile reports written out. The program runs forever and otherwise generates no profile reports when I interrupt it. I install the handlers like this: installHandler sigPIPE Ignore Nothing flip mapM_ [sigINT, sigHUP, sigABRT, sigTERM] $ \sig -> do installHandler sig handler Nothing where handler = Catch $ exitWith (ExitFailure 1) P.S. Is there a prize of some sorts for the highest number of wierd bug reports per time frame? :D -- http://wagerlabs.com/