Horton

Re: Optimizing pg_trgm makesign() (was Re: WIP: Fast GiST index build)

Robert Haas <robertmhaas@gmail.com>

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From: Robert Haas <robertmhaas@gmail.com>
To: Heikki Linnakangas <heikki.linnakangas@enterprisedb.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>, Alexander Korotkov <aekorotkov@gmail.com>
Date: 2011-06-24T19:22:15Z
Lists: pgsql-hackers 
On Fri, Jun 24, 2011 at 3:01 PM, Heikki Linnakangas
<heikki.linnakangas@enterprisedb.com> wrote:
> On 24.06.2011 21:24, Robert Haas wrote:
>>
>> Out of curiosity (and because there is no comment or Assert here), how
>> can you be so sure of the input alignment?
>
> The input TRGM to makesign() is a varlena, so it must be at least 4-byte
> aligned. If it was not for some reason, the existing VARSIZE invocation
> (within GETARR()) would already fail on platforms that are strict about
> alignment.

Hmm, OK.  Might be worth adding a comment, anyway...

-- 
Robert Haas
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