./randomplay +RTS -hr ... <- some time passes and then randomplay: internal error: Invalid object in isRetainer(): 67 Please report this as a bug to glasgow-haskell-bugs@haskell.org, or http://www.sourceforge.net/projects/ghc/ The combination of this and the failure with -hc -hbdrag,void is preventing me from optimizing the program and it has a huge space leak somewhere. Thanks, Joel -- http://wagerlabs.com/