Re: question on bits32 wraparound check

Alvaro Herrera <alvherre@commandprompt.com> writes:
> So there's a minor issue on Takahiro-san fillfactor-on-toast patch,
> which is that it does not hand out the last possible "kind" value.  This
> is a bits32 field, so at least theoretically on some platforms it will
> be wider than 32 while on others it will be exactly 32.

So just disallow kind > 31 (hard wired, with a note cross-referencing
the datatype definition).  Even if that leaves some unused bits on some
particular platform, it's correct and ensures portable behavior.
        regards, tom lane