Re: RFC: next/finish/etc -vs- exceptions

Daniel Jacobowitz
2009-06-10T17:13:40Z

On Wed, Jun 10, 2009 at 06:06:31PM +0100, Pedro Alves wrote:
> I assume that exceptions have a property that raw longjmp doesn't,
> which is what makes stepping over longjmp complicated --- they never
> switch to alternate stacks? That was one reason why comparing
> frame/stack pointers with inner_than kind of comparisions is
> verboten (to know when the longjmp/exception is all inner to the
> step/next and can be ignored, for example). That, and frames
> crossing architectures, like on Cell. I did spot one such comparision
> by a quick look at the patch, but I don't know if it OK to do so in
> your case or not. I assume other people who know more about
> frames and unwinders than me can provide better input there. :-)

Not sure what you mean exactly, but exceptions can be thrown through
signal handlers on many platforms; so yes, they might switch stack.
They could go to any stack higher on the call frame.

--
Daniel Jacobowitz
CodeSourcery