[racket] Some DrRacket instability--gc-related?

I don't think anything changed recently in the run-time system that
would be likely to create this kind of bug, but it's difficult to be
certain. (That's not much help, I know.)

At Tue, 8 Apr 2014 15:40:48 -0700, John Clements wrote:
> Since recompiling the HEAD earlier today, I’m getting some crashes in
> DrRacket. They appear to be occurring during GC. Stack trace
> attached. Now, it’s entirely possible that this could be related to
> bugs in my code, specifically my RSound package, which has the means
> (and the desire?) to break things. Nevertheless, I haven’t seen a
> crash in quite a number of weeks, and now two in an hour, so there
> could be something here that affects other users.
> 
> John