Received: from malur.postgresql.org ([217.196.149.56])
	by arkaria.postgresql.org with esmtps
 (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256)
	(Exim 4.89)
	(envelope-from <pgsql-www-owner+archive@lists.postgresql.org>)
	id 1ew93m-0001HJ-Vo
	for pgsql-www@arkaria.postgresql.org; Wed, 14 Mar 2018 16:15:27 +0000
Received: from localhost ([127.0.0.1] helo=malur.postgresql.org)
	by malur.postgresql.org with esmtp (Exim 4.89)
	(envelope-from <pgsql-www-owner+archive@lists.postgresql.org>)
	id 1ew93l-0001Fg-RU
	for pgsql-www@arkaria.postgresql.org; Wed, 14 Mar 2018 16:15:25 +0000
Received: from makus.postgresql.org ([2001:4800:1501:1::229])
	by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256)
	(Exim 4.89)
	(envelope-from <tgl@sss.pgh.pa.us>)
	id 1ew93l-0001FV-Ja
	for pgsql-www@lists.postgresql.org; Wed, 14 Mar 2018 16:15:25 +0000
Received: from sss.pgh.pa.us ([66.207.139.130])
	by makus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256)
	(Exim 4.89)
	(envelope-from <tgl@sss.pgh.pa.us>)
	id 1ew93i-0002QV-7p
	for pgsql-www@lists.postgresql.org; Wed, 14 Mar 2018 16:15:24 +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 w2EGFH3r004711;
	Wed, 14 Mar 2018 12:15:17 -0400
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@alvh.no-ip.org>
cc: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>,
        Stephen Frost <sfrost@snowman.net>,
        Magnus Hagander <magnus@hagander.net>,
        PostgreSQL WWW <pgsql-www@lists.postgresql.org>
Subject: Re: Bogus reports from coverage.postgresql.org
In-reply-to: <20180314154352.ao4psdohgxd4pw65@alvherre.pgsql>
References: <20180314154352.ao4psdohgxd4pw65@alvherre.pgsql>
Comments: In-reply-to Alvaro Herrera <alvherre@alvh.no-ip.org>
	message dated "Wed, 14 Mar 2018 12:43:52 -0300"
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <4709.1521044117.1@sss.pgh.pa.us>
Content-Transfer-Encoding: quoted-printable
Date: Wed, 14 Mar 2018 12:15:17 -0400
Message-ID: <4710.1521044117@sss.pgh.pa.us>
List-Id: <pgsql-www.lists.postgresql.org>
List-Help: <https://lists.postgresql.org/manage/>
List-Subscribe: <https://lists.postgresql.org/manage/>
List-Post: <mailto:pgsql-www@lists.postgresql.org>
List-Owner: <mailto:pgsql-www-owner@lists.postgresql.org>
List-Archive: <https://www.postgresql.org/list/pgsql-www>
Precedence: bulk

Alvaro Herrera <alvherre@alvh.no-ip.org> writes:
> In the coverage.pg.org box, we have:
> $ cat .lcovrc =

> lcov_branch_coverage =3D 1

Oh, that's critical information not mentioned before :-(.

On my Fedora 26 box (gcc 7.3.1) I can reproduce the problem after
setting up ~/.lcovrc that way:

$ grep bogus  coverage/src/backend/optimizer/util/predtest.c.*
coverage/src/backend/optimizer/util/predtest.c.gcov.html:<span class=3D"li=
neNum">     492 </span>                :<span class=3D"lineCov">      1020=
8 :     elog(ERROR, &quot;predicate_classify returned a bogus value&quot;)=
;</span>
coverage/src/backend/optimizer/util/predtest.c.gcov.html:<span class=3D"li=
neNum">     803 </span>                :<span class=3D"lineCov">      5948=
2 :     elog(ERROR, &quot;predicate_classify returned a bogus value&quot;)=
;</span>

(note "lineCov" instead of expected "lineNoCov").  This happens
with either lcov 1.12 or 1.13.  I also notice an interesting
warning with either version:

$ make coverage-html
/usr/bin/lcov --gcov-tool /usr/bin/gcov -q --no-external -c -i -d . -d . -=
o lcov_base.info
geninfo: Note: --initial does not generate branch coverage data
/usr/bin/lcov --gcov-tool /usr/bin/gcov -q --no-external -c -d . -d . -o l=
cov_test.info
rm -rf coverage
/usr/bin/genhtml -q --legend -o coverage --title=3D'PostgreSQL 11devel' --=
num-spaces=3D4 --prefix=3D'/home/tgl/pgsql' lcov_base.info lcov_test.info
touch coverage-html-stamp

No idea what "--initial" refers to, but it suggests that we're
misusing the tool somehow with this configuration.

			regards, tom lane