Yves Arrouye writes ("Re: Pb: gdb cannot read core from 2.0.8 (is it a gdb or kernel problem)?"):
...
> But the message is really misleading... It would ne nice if Gdb checked
> wether the prog arg was a core first, and in this case tell that's the
> case and remind usage. (Not that I ask that it does that: I should have
> read the manual page, of course.)
You might also see my bug report, #3515.
Ian.