step_range_(start|end)

[Pete Wyckoff <pw@osc.edu>]

I'm trying to shape up my remote backend to gdb so that it's happy with
things that 5.1 is sending it.  One of these is, for example, "e1,1".
Although gdb is content to accept an error from the remote and issue "s"
(step) instead, I thought it would be nice to make "e" work too.

My confusion, though, is about the two parameters.  There's no entry in
the documentation for 'e', and I find it passing two variables:

    step_range_start
    step_range_end

These are defined as CORE_ADDR, and filled with calls like

    find_pc_line_pc_range (stop_pc, &step_range_start, &step_range_end);

which makes sense to me, but then I see other places like:

      step_range_start = step_range_end = 1;

which sure don't sound like CORE_ADDRs.

What should I do with an 'e' command in the remote backend (other than
ignore it)?

		-- Pete