Re: reducing the footprint of ScanKeyword (was Re: Large writable variables) - Mailing list pgsql-hackers

From John Naylor
Subject Re: reducing the footprint of ScanKeyword (was Re: Large writable variables)
Date
Msg-id CAJVSVGUCxUaDPPsz9X0dVvt416WUR=g7kLgCVd=_V-EKo9eNDg@mail.gmail.com
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In response to Re: reducing the footprint of ScanKeyword (was Re: Large writablevariables)  (Andres Freund <andres@anarazel.de>)
Responses Re: reducing the footprint of ScanKeyword (was Re: Large writable variables)  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-hackers
On 12/30/18, Andres Freund <andres@anarazel.de> wrote:
> I tried to take this for a spin, an for me the build fails because various
> frontend programs don't have KeywordOffsets/Strings defined, but reference
> it
> through various functions exposed to the frontend (like fmtId()).  That I
> see
> that error but you don't is probably related to me using -fuse-ld=gold in
> CFLAGS.
>
> I can "fix" this by including kwlist_d.h in common/keywords.c
> regardless of FRONTEND. That also lead me to discover that the build
> dependencies somewhere aren't correctly set-up, because I need to
> force a clean rebuild to trigger the problem again, just changing
> keywords.c back doesn't trigger the problem.

Hmm, that was a typo, and I didn't notice even when I found I had to
include kwlist_d.h in ecpg/keywords.c. :-(  I've fixed both of those
in the attached v6.

As far as dependencies, I'm far from sure I have it up to par. That
piece could use some discussion.

On 1/4/19, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Aside from the possible linkage problem, this will need a minor rebase
> over 4879a5172, which rearranged some of plpgsql's calls of
> ScanKeywordLookup.
>
> While I don't think it's going to be hard to resolve these issues,
> I'm wondering where we want to go with this.  Is anyone excited
> about pursuing the perfect-hash-function idea?  (Joerg's example
> function looked pretty neat to me.)  If we are going to do that,
> does it make sense to push this version beforehand?

If it does, for v6 I've also done the rebase, updated the copyright
year, and fixed an error in MSVC.

-John Naylor

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