Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas - Mailing list pgsql-hackers

From Michael Paquier
Subject Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas
Date
Msg-id YkaP64JvZTMgcHtq@paquier.xyz
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In response to Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas  (Matthias van de Meent <boekewurm+postgres@gmail.com>)
Responses Re: Preventing indirection for IndexPageGetOpaque for known-size page special areas
List pgsql-hackers
On Thu, Mar 31, 2022 at 12:09:35PM +0200, Matthias van de Meent wrote:
> PageInit MAXALIGNs the size of the special area that it receives as an
> argument; so any changes to the page header that would misalign the
> value would be AM-specific; in which case it is quite unlikely that
> this is the right accessor for your page's special area.

Right.  I'd still be tempted to keep that per-AM rather than making
the checks deeper with one extra macro layer in the page header or
with a different macro that would depend on the opaque type, though.
Like in the attached, for example.
--
Michael

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