Date: Tue, 18 Aug 2020 18:02:46 +0200
From: Jehan-Guillaume de Rorthais <jgdr@dalibo.com>
To: Peter Geoghegan <pg@bowt.ie>
Cc: Thomas Munro <thomas.munro@gmail.com>, =?UTF-8?B?0KDQvtC80LDQvSDQm9C4?=
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 PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>
Subject: Re: BUG #15285: Query used index over field with ICU collation in
 some cases wrongly return 0 rows
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Hi Peter,

On Tue, 11 Aug 2020 21:14:03 -0700
Peter Geoghegan <pg@bowt.ie> wrote:

> On Fri, Jun 12, 2020 at 3:43 PM Jehan-Guillaume de Rorthais
> <jgdr@dalibo.com> wrote:
> > Please, find in attachment the second version of the patch, with a
> > regression test.
> 
> Is it possible to fix this by making the existing
> HAVE_UCOL_STRCOLLUTF8 test more conservative about ICU version? IOW,
> by making it only use ucol_strcollUTF8() on versions that are known to
> not be affected by this bug?

I might be missing something, but according to my tests back in June, the bug
exists in both ucol_strcollUTF8()/ucol_strcoll() and is still affecting the very
last version of ICU (67.1).

That's why my patch replaces both functions altogether using ucol_strcollIter
as replacement.

> This related ICU bug describes an issue affecting only versions 53/54:
> 
> https://unicode-org.atlassian.net/browse/ICU-11388

This bug is related to ICU4J, not ICU4C. AS far as I understand, this was
related to a bad variable type when porting the code to java. Do I miss
something?

Regards,