using backtrace() in exception throwing?

Hi

Background: I'm looking at bug reports, and the messages are generally only
marginally useful, because I generally have no idea where the original
exception was actually thrown from.
Sometimes the message in the exception will narrow it down a little, but
that still often leaves a lot of likely places, and often the information
I'm really interested in, is a few frames worth of callng stack information.

What would be the costs of calling backtrace()
   http://www.gnu.org/software/libc/manual/html_node/Backtraces.html
in the exception base class, storing a few frames worth of data,
and then modifying the exception printing code to call
  backtrace_symbols()
when writing out the exception?

For me personally, this would really speed up tracking down the source of
bugs.

Regards, Noel Grandin