[Crash-utility] [RFC] display function param and local value for backtrace

[Dave Anderson]

----- Original Message -----
> > Hello Lei,
> > 
> > 
> > And it appears that target_read_stack() can be modified in the same
> > way
> > that target_read_memory() has been, since they are essentially the
> > same:
> > 
> >   int
> >   target_read_stack (CORE_ADDR memaddr, gdb_byte *myaddr, int len)
> >   {
> >   }
> > 
> > So just try cut-and-pasting the same #ifdef CRASH_MERGE section into
> > target_read_stack().
> 
> Yep, it did solve my issue, now the backtrace would unwind happily to
> the next frame.
> 
> While I am trying to apply the similar logic to another thread
> instead of current panic one, I find the gdb would directly complain
> for "<segmentation violation in gdb> ". Haven't figure out what
> happened there...

When gdb is invoked, it passes through this in gdb_interface():

        if (!(pc->flags & DROP_CORE))
                SIGACTION(SIGSEGV, restart, &pc->sigaction, NULL);
        else
                SIGACTION(SIGSEGV, SIG_DFL, &pc->sigaction, NULL);

which causes any segmentation violations in gdb code to restart back
to the command prompt.  To get an actual core dump (to set DROP_CORE),
try this:

  crash> set core on
  core: on (drop core on error message)
  crash>

If you do the above, however, any call to error(FATAL, ...),
error(INFO, ...), or error(WARNING, ...) will also generate
a core dump.  If that gets in the way of your gdb testing, you
should just comment out the "if-else" statement above.

Dave