Strange looping

[Lennart Borgman]

I have experience some strange looping in Emacs recently. I have
difficulties catching them, but with a recent build I was able to use
Emacs to see what happened.

I found no reason. I killed all visible buffers, but Emacs still
loops. There are no processes that I can see. I did not see anything
really suspect - except for an arg out or range during fontification.

I think I have seen the same problem with builds from 2010-03-21 and
2010-04-27. (This are my patched builds, though.)

Anyone has any good idea of how to catch this?