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Subject: Re: Patches to build GDB 6.3
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> Can you post a short explaination what is special about C++ exceptions
> that reveals the problem only there?  Do C++ exceptions use some
> special registers that are unused anywhere else?

C++ uses the EH unwind information to rewrite the stack frames to
"undo" multiple levels of call frames in one shot.  It's not only one
of the strangest things to debug, but it's second on our bug list
after optimization failures.

Think of it as a longjmp() on hallucinogens.