Re: [libunwind] Unwinding using the context passed to a signal handler (doesn't work)

[Max Asbock]

On x86_64 we can't currently unwind across signal frames using dwarf2
info. The kernel doesn't export that information yet.
See http://www.x86-64.org/lists/discuss/msg04811.html
Therefore even if we call unw_getcontext() from the signal handler and
unwind back till we hit the signal frame, we still have to pick out the
values for the next SP and IP from the ucontext on the signal frame. I
am not sure if this is different from using the same ucontext passed in
by the signal handler directly.

max
 

On Fri, 2004-03-26 at 11:03, Young, Mark wrote:
> David,
> 
> Do all platforms make the same distinction between asynchronous
> (signal) and synchronous contexts?
> 
> I like Johan's suggestion of an alternate unw_init_local interface
> (unw_init_from_signal_context_local) that takes the signal context as
> the starting point. From what you are saying, an ia64 implementation
> of this would have to ignore the signal context, call getcontext, and
> unwind until it found the signal frame. But is that true for all
> platforms?
>