> ./randomplay +RTS -hr
> ... <- some time passes and then
> randomplay: internal error: Invalid object in isRetainer(): 67
> Please report this as a bug to [hidden email],
> 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.
Retainer profiling (-hr) doesn't currently work with STM. It is a bug,
but I briefly looked into it and it's not a trivial fix so I left it.
I'll file a ticket for it.