unwind question

[Martin v. Loewis]

Dietmar Maurer <dietmar@ximian.com> writes:

> Can someone explain the big difference between async an sync signals
> (concerning exception tables)?

I can't explain the precise details, but according to the
documentation, for asynchronous signals, the register tables are precise to
the instruction level. 

There is no such thing as synchronous signals - the opposite of
supporting async signals is to not support them (POSIX signals are
always asynchronous).

If the compiler does not support async signals, it can drop register
lifeness information for instructions that are not on a call boundary,
which significantly reduces the size of the unwind tables.

Regards,
Martin