Re: Compiler warning with 'fast' variable

Bruce Momjian <bruce@momjian.us> writes:
> Any idea why I am seeing this warning with the new pg_start_backup()
> 'fast' flag?

>     xlog.c:6917: warning: variable `fast' might be clobbered by
>     `longjmp' or `vfork'

> The line is in a PG_ENSURE_ERROR_CLEANUP() block.  This is with gcc
> version 2.95.3.

That's pretty bizarre --- I don't see it here with gcc 2.95.3,
and there is no reason for such a warning to appear on a variable
that isn't changed during the function.

We could stick a volatile on it but I'd like to find out why this
particular variable seems to need that.
        regards, tom lane