[libunwind] libunwind bk repository updated

[David Mosberger]

Just pushed a fairly large change set into the bitkeeper repo (see
http://unwind.bkbits.net:8080/libunwind/address@hidden).  This one pretty
much completes implementation of the dynamic unwind support.  In
particular, the code for remote unwinding of dynamically generated
code is there now, though it's untested at the moment.  Perhaps almost
more important is that I'm finally happy with the way memory
management is done for the unwind-info.  Basically, when you do a
find_proc_info() callback, libunwind specifies whether or not it needs
the unwind-info.  If it's not needed, no memory has to be allocated by
the callback.  If it's needed, the underlying memory is freed later
via the put_unwind_info() callback.  The unwind info is retained just
long enough to parse it, so there is no callback-allocated memory
anymore that lives beyond a single invocation of an API routine.

I think I also took care of the various concerns that Mark had.  In
particular, the proc_info is now obtained lazily.  Might even help
performance for those cases that do not need to proc_info.

Enjoy,

        --david