Re: [patch] Re: longjmp handling vs. glibc LD_POINTER_GUARD problems

Daniel Jacobowitz
2008-05-21T19:44:20Z

On Wed, May 21, 2008 at 09:20:19PM +0200, Ulrich Weigand wrote:
> Another issue with your patch is the use of frame_id_inner ... I'd rather
> get rid of this function instead of adding new uses, because this really
> requires that it is possible to compare two stack (frame) addresses
> along a linear order. This breaks for me in multi-architecture scenarios,
> but even on existing targets it may not always work OK (e.g. if signal
> handlers run on a different frame, or if the code uses some sort of
> user-level threading or coroutine library ...). Maybe instead of
> comparing frame_ids, it would be better to check whether or not a
> frame with the given ID still exists in the current backtrace?

Let's be careful, if doing that, that we don't search too far up the
stack chain. Infinite stacks are a not uncommon failure mode when
something's gone wrong in GDB...

--
Daniel Jacobowitz
CodeSourcery