Received: from malur.postgresql.org ([217.196.149.56])
	by arkaria.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256)
	(Exim 4.89)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1hoK9q-0007iP-FF
	for pgsql-hackers@arkaria.postgresql.org; Fri, 19 Jul 2019 04:06:10 +0000
Received: from localhost ([127.0.0.1] helo=malur.postgresql.org)
	by malur.postgresql.org with esmtp (Exim 4.89)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1hoK9o-0008PB-Sm
	for pgsql-hackers@arkaria.postgresql.org; Fri, 19 Jul 2019 04:06:08 +0000
Received: from makus.postgresql.org ([2001:4800:3e1:1::229])
	by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256)
	(Exim 4.89)
	(envelope-from <tgl@sss.pgh.pa.us>)
	id 1hoK9o-0008Fn-D3
	for pgsql-hackers@lists.postgresql.org; Fri, 19 Jul 2019 04:06:08 +0000
Received: from sss.pgh.pa.us ([66.207.139.130])
	by makus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256)
	(Exim 4.92)
	(envelope-from <tgl@sss.pgh.pa.us>)
	id 1hoK9k-0008Iy-GW
	for pgsql-hackers@lists.postgresql.org; Fri, 19 Jul 2019 04:06:07 +0000
Received: from sss1.sss.pgh.pa.us (localhost [127.0.0.1])
	by sss.pgh.pa.us (8.14.4/8.14.4) with ESMTP id x6J4617U031997;
	Fri, 19 Jul 2019 00:06:01 -0400
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Michael Paquier <michael@paquier.xyz>
cc: Postgres hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: pgsql: Sync our copy of the timezone library with IANA release
 tzcode20
In-reply-to: <20190719035347.GJ1859@paquier.xyz>
References: <E1hnsNp-0007u8-PD@gemulon.postgresql.org>
 <20190719035347.GJ1859@paquier.xyz>
Comments: In-reply-to Michael Paquier <michael@paquier.xyz>
	message dated "Fri, 19 Jul 2019 12:53:47 +0900"
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <31995.1563509161.1@sss.pgh.pa.us>
Date: Fri, 19 Jul 2019 00:06:01 -0400
Message-ID: <31996.1563509161@sss.pgh.pa.us>
List-Id: <pgsql-hackers.lists.postgresql.org>
List-Help: <https://lists.postgresql.org/manage/>
List-Subscribe: <https://lists.postgresql.org/manage/>
List-Post: <mailto:pgsql-hackers@lists.postgresql.org>
List-Owner: <mailto:pgsql-hackers-owner@lists.postgresql.org>
List-Archive: <https://www.postgresql.org/list/pgsql-hackers>
Precedence: bulk

Michael Paquier <michael@paquier.xyz> writes:
> This is causing a compilation warning on Windows:

>  src/timezone/zic.c(2401): warning C4804: '-' : unsafe use of type
>   'bool' in operation

Hmmm ... the code looks like

        bool        locut,
                    hicut;
        ...
        thistimecnt = -locut - hicut;

so I think your compiler has a point.  I shall complain to upstream.
At best, it's really unobvious what this code is meant to do, and
at worst (eg, depending on whether bool promotes to signed or unsigned
int) the results are unportable.

			regards, tom lane