> When I get back I'll build dump with -g and I can then attach to it
> with gdb next time it does this.  That will be in a few days.

I build -current's dump and it ran last night.  As far as I can tell
rcache.c:bread() is in an infinite loop.  This file is new since 1.3.x
which may explain the breakage.  Sorting out what's going on isn't
helped by gdb saying 'No symbol "toCopy" in current context.' etc.

I can modify the code so that interesting vars are not buried within
narrow contexts where they are hard to access, but is there a reliable
way to stop gcc optimizing them away?

--sjg