On Wed, Jun 22, 2022 at 4:24 PM Thomas Munro <thomas.munro@gmail.com> wrote:
> On Wed, Jun 22, 2022 at 2:54 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> > John Naylor <john.naylor@enterprisedb.com> writes:
> > > On Wed, Jun 1, 2022 at 2:57 AM Robert Haas <robertmhaas@gmail.com> wrote:
> > >> ... So we can fix this by:
> > >> 1. Using a relative pointer value other than 0 to represent a null
> > >> pointer. Andres suggested (Size) -1.
> > >> 2. Not storing the free page manager for the DSM in the main shared
> > >> memory segment at byte offset 0.
>
> For the record, the third idea proposed was to use 1 for the first
> byte, so that 0 is reserved for NULL and works with memset(0). Here's
> an attempt at that.
... erm, though, duh, I forgot to adjust Assert(val > base). One more time.