Josh Berkus <josh(at)agliodbs(dot)com> writes:
> Problem: the script which dumps globals such as users (pg_dumpall -g)
> involves deleting *all* users from the pg_shadow table via a direct update to
> that table.
AFAICS that happens only if you've specified the -c (--clean) option.
Hence, I don't think it's a bug.
regards, tom lane