GNU bug report logs - #35526
misleading documentation about flag variable ordering

Please note: This is a static page, with minimal formatting, updated once a day.
Click here to see this page with the latest information and nicer formatting.

Package: automake; Reported by: Daniel Kahn Gillmor <dkg@HIDDEN>; dated Wed, 1 May 2019 17:34:01 UTC; Maintainer for automake is bug-automake@HIDDEN.

Message received at 35526 <at> debbugs.gnu.org:


Received: (at 35526) by debbugs.gnu.org; 1 May 2019 18:41:42 +0000
From debbugs-submit-bounces <at> debbugs.gnu.org Wed May 01 14:41:42 2019
Received: from localhost ([127.0.0.1]:44900 helo=debbugs.gnu.org)
	by debbugs.gnu.org with esmtp (Exim 4.84_2)
	(envelope-from <debbugs-submit-bounces <at> debbugs.gnu.org>)
	id 1hLuAn-00047v-St
	for submit <at> debbugs.gnu.org; Wed, 01 May 2019 14:41:42 -0400
Received: from che.mayfirst.org ([162.247.75.118]:56479)
 by debbugs.gnu.org with esmtp (Exim 4.84_2)
 (envelope-from <dkg@HIDDEN>) id 1hLuAm-00047n-A6
 for 35526 <at> debbugs.gnu.org; Wed, 01 May 2019 14:41:40 -0400
DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/simple; 
 d=fifthhorseman.net; i=@fifthhorseman.net; q=dns/txt; 
 s=2019; t=1556736099; h=from : to : cc : subject : 
 in-reply-to : references : date : message-id : 
 mime-version : content-type : content-transfer-encoding : 
 from; bh=846HTacGmvQGEPlHWOTvSsd55s0+KWUYrntwuYQAmrA=; 
 b=0/eURIn1C5SYcYEZxCOZrUFMB9Y4sLTn7DbxiTzreVJQaTDqnchVhqpD
 QC2EKLFn9hPQb4ueVhzZxxOGNkFhCw==
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=fifthhorseman.net; 
 i=@fifthhorseman.net; q=dns/txt; s=2019rsa; t=1556736098; 
 h=from : to : cc : subject : in-reply-to : references : 
 date : message-id : mime-version : content-type : 
 content-transfer-encoding : from; 
 bh=846HTacGmvQGEPlHWOTvSsd55s0+KWUYrntwuYQAmrA=; 
 b=rwf1JHY930T6F3zxZuCp10xisU4FPm9ETOruG6IBfnJG8I2JGT5HNO6v
 d+GlVsMZFvgO/GJFm3F4IVKPRibHyZldghzvnNOQuwIxRs0Kgs269UEKDn
 /XFx7Qj+XNBsumeyr3FIhFZzIp34I/AfYLjL/vDfmPNGZQpdjl/VfFCJGO
 aSzZabDuUpTFfjlExxe2s1LUA4Ks9BK5uizN3+3o/4X2IwhMSTjcAVk9q1
 r/aa5KApO4TCkBloi6q50mefAbOWSTv/rSznqRJ0/x8jQ+YXkJG3icb5xr
 GxN/x8F1app1yQhc/RZcko0sew0EZCt9BPkogq2ZnOr9Sa/pYT1XWQ==
Received: from fifthhorseman.net (unknown [38.109.115.130])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (No client certificate requested)
 by che.mayfirst.org (Postfix) with ESMTPSA id D9D33F99E;
 Wed,  1 May 2019 14:41:38 -0400 (EDT)
Received: by fifthhorseman.net (Postfix, from userid 1000)
 id 21252202A1; Wed,  1 May 2019 14:40:45 -0400 (EDT)
From: Daniel Kahn Gillmor <dkg@HIDDEN>
To: Nick Bowler <nbowler@HIDDEN>
Subject: Re: bug#35526: misleading documentation about flag variable ordering
In-Reply-To: <CADyTPEzSTA=EmycitAXcsJrpj68L145+OkRZKsMBLrUKmqc2cA@HIDDEN>
References: <87zho6ozab.fsf@HIDDEN>
 <CADyTPEzSTA=EmycitAXcsJrpj68L145+OkRZKsMBLrUKmqc2cA@HIDDEN>
Autocrypt: addr=dkg@HIDDEN; prefer-encrypt=mutual; keydata=
 mDMEXEK/AhYJKwYBBAHaRw8BAQdAr/gSROcn+6m8ijTN0DV9AahoHGafy52RRkhCZVwxhEe0K0Rh
 bmllbCBLYWhuIEdpbGxtb3IgPGRrZ0BmaWZ0aGhvcnNlbWFuLm5ldD6ImQQTFggAQQIbAQUJA8Jn
 AAULCQgHAgYVCgkICwIEFgIDAQIeAQIXgBYhBMS8Lds4zOlkhevpwvIGkReQOOXGBQJcQsbzAhkB
 AAoJEPIGkReQOOXG4fkBAO1joRxqAZY57PjdzGieXLpluk9RkWa3ufkt3YUVEpH/AP9c+pgIxtyW
 +FwMQRjlqljuj8amdN4zuEqaCy4hhz/1DbgzBFxCv4sWCSsGAQQB2kcPAQEHQERSZxSPmgtdw6nN
 u7uxY7bzb9TnPrGAOp9kClBLRwGfiPUEGBYIACYWIQTEvC3bOMzpZIXr6cLyBpEXkDjlxgUCXEK/
 iwIbAgUJAeEzgACBCRDyBpEXkDjlxnYgBBkWCAAdFiEEyQ5tNiAKG5IqFQnndhgZZSmuX/gFAlxC
 v4sACgkQdhgZZSmuX/iVWgD/fCU4ONzgy8w8UCHGmrmIZfDvdhg512NIBfx+Mz9ls5kA/Rq97vz4
 z48MFuBdCuu0W/fVqVjnY7LN5n+CQJwGC0MIA7QA/RyY7Sz2gFIOcrns0RpoHr+3WI+won3xCD8+
 sVXSHZvCAP98HCjDnw/b0lGuCR7coTXKLIM44/LFWgXAdZjm1wjODbg4BFxCv50SCisGAQQBl1UB
 BQEBB0BG4iXnHX/fs35NWKMWQTQoRI7oiAUt0wJHFFJbomxXbAMBCAeIfgQYFggAJhYhBMS8Lds4
 zOlkhevpwvIGkReQOOXGBQJcQr+dAhsMBQkB4TOAAAoJEPIGkReQOOXGe/cBAPlek5d9xzcXUn/D
 kY6jKmxe26CTws3ZkbK6Aa5Ey/qKAP0VuPQSCRxA7RKfcB/XrEphfUFkraL06Xn/xGwJ+D0hCw==
Date: Wed, 01 May 2019 14:40:44 -0400
Message-ID: <87o94mow5v.fsf@HIDDEN>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 8bit
X-Spam-Score: 0.0 (/)
X-Debbugs-Envelope-To: 35526
Cc: 35526 <at> debbugs.gnu.org
X-BeenThere: debbugs-submit <at> debbugs.gnu.org
X-Mailman-Version: 2.1.18
Precedence: list
List-Id: <debbugs-submit.debbugs.gnu.org>
List-Unsubscribe: <https://debbugs.gnu.org/cgi-bin/mailman/options/debbugs-submit>, 
 <mailto:debbugs-submit-request <at> debbugs.gnu.org?subject=unsubscribe>
List-Archive: <https://debbugs.gnu.org/cgi-bin/mailman/private/debbugs-submit/>
List-Post: <mailto:debbugs-submit <at> debbugs.gnu.org>
List-Help: <mailto:debbugs-submit-request <at> debbugs.gnu.org?subject=help>
List-Subscribe: <https://debbugs.gnu.org/cgi-bin/mailman/listinfo/debbugs-submit>, 
 <mailto:debbugs-submit-request <at> debbugs.gnu.org?subject=subscribe>
Errors-To: debbugs-submit-bounces <at> debbugs.gnu.org
Sender: "Debbugs-submit" <debbugs-submit-bounces <at> debbugs.gnu.org>
X-Spam-Score: -1.0 (-)

On Wed 2019-05-01 14:28:01 -0400, Nick Bowler wrote:
> On 5/1/19, Daniel Kahn Gillmor <dkg@HIDDEN> wrote:
>> https://www.gnu.org/software/automake/manual/automake.html#Flag-Variables-Ordering
>> says:
>>
>>     The reason ‘$(CPPFLAGS)’ appears after ‘$(AM_CPPFLAGS)’ or
>>     ‘$(mumble_CPPFLAGS)’ in the compile command is that users should
>>     always have the last say.
 […]
> The manual can always be improved.  Do you have a suggestion for how to
> write this paragraph to make it better?

maybe replace "users should always have the last say." with:

    most configuration options for the standard toolchain can be
    overridden later on the command line, and in those circumstances the
    user should have the last say.

(including some of the nuance you've written upthread here or elsewhere
in the manual would be great too)

Thanks for the prompt and thoughtful rsponse!

       --dg




Information forwarded to bug-automake@HIDDEN:
bug#35526; Package automake. Full text available.

Message received at 35526 <at> debbugs.gnu.org:


Received: (at 35526) by debbugs.gnu.org; 1 May 2019 18:28:10 +0000
From debbugs-submit-bounces <at> debbugs.gnu.org Wed May 01 14:28:10 2019
Received: from localhost ([127.0.0.1]:44887 helo=debbugs.gnu.org)
	by debbugs.gnu.org with esmtp (Exim 4.84_2)
	(envelope-from <debbugs-submit-bounces <at> debbugs.gnu.org>)
	id 1hLtxi-0003oQ-G2
	for submit <at> debbugs.gnu.org; Wed, 01 May 2019 14:28:10 -0400
Received: from mail-lj1-f195.google.com ([209.85.208.195]:41833)
 by debbugs.gnu.org with esmtp (Exim 4.84_2)
 (envelope-from <nbowler@HIDDEN>) id 1hLtxg-0003oD-Dj
 for 35526 <at> debbugs.gnu.org; Wed, 01 May 2019 14:28:09 -0400
Received: by mail-lj1-f195.google.com with SMTP id k8so16165074lja.8
 for <35526 <at> debbugs.gnu.org>; Wed, 01 May 2019 11:28:08 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=draconx-ca.20150623.gappssmtp.com; s=20150623;
 h=mime-version:in-reply-to:references:from:date:message-id:subject:to
 :cc:content-transfer-encoding;
 bh=92W+/PRUThQ0FE9IuXO27FyW+1E30zxrzMFm6Tm03Zs=;
 b=jTRgu8nYa8fn/G/n6RUILDFWlUAcp1PRLSt6eAxrYlVydDEsAif6cDFJLY+CX9/5S0
 ewV2wW1zXGoyN+zO3lWqf07YIAMm9uZrtjWKZ9QMS/A2eY8gdaIuDxazFC9PzNJal2u/
 vJrJ8zzeOWsRHfbVmmfliRGK5YjiTD6R26iryiVoH7LGPMm5OyT3iKdoOeelPCfb4Obt
 m7qgXKfhhQ97feMvcgSZGbSVXnCzw05oqdeCdkhbtwzGirXCeOJUQdxC5HNvTQAuKFuo
 SiqN8Yuh2A9SGzT8gSmTeBYZyAJdsib5nlCC/WvJDuMq3jZT43X/QBceVvcBMBNwoQaF
 rAbg==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=1e100.net; s=20161025;
 h=x-gm-message-state:mime-version:in-reply-to:references:from:date
 :message-id:subject:to:cc:content-transfer-encoding;
 bh=92W+/PRUThQ0FE9IuXO27FyW+1E30zxrzMFm6Tm03Zs=;
 b=bj+MhVJU1lEp2WQx1cKQtO9/LeJZ8ey1lu7sw9RAHhhVsJLinhEYvvKavTwzsJ1m6g
 r6ie9Styl/JSRdPAZGrx2hmJsZpz9crI8EY/5e7OVNESl1pWnlymAgtySnEVfGnAMny0
 if3ycWYb0HUu/JKFWxc17jtlMEezqgHmV0Ej25YZF7ORe93gM0iHYwi3evdK00NuheLr
 2ImkYXKCK8vHo+z2iGsEjRGfPXNin0a3l6WxGk/Afr083Heclm9rpZGkMW1fGUirb8zx
 sC8uYqxzt8XIwZSK9lB1aoPu0Qu6we7ENje5YjaIe18a8xslfXxxeUHVjrOk24tHDYRg
 XxHg==
X-Gm-Message-State: APjAAAXduBblwkT7DjmQCpNSxbUkW7zZJtLlBrcg/DvPkBJsn/76e6Yj
 yDqKA6qep/JKVGMPyBug5CAsBcKpLFw9Lic6kBMtfxb/1A1QVw==
X-Google-Smtp-Source: APXvYqxbWBUwSlvMTTXoSN8Ektbgw356NjK/qIod4//EGjHFNDjJYZQMt+C/pDno5u0PI8p+tGfbBFmaE/13Cys3RFs=
X-Received: by 2002:a2e:7605:: with SMTP id r5mr1122595ljc.109.1556735282364; 
 Wed, 01 May 2019 11:28:02 -0700 (PDT)
MIME-Version: 1.0
Received: by 2002:a2e:455:0:0:0:0:0 with HTTP;
 Wed, 1 May 2019 11:28:01 -0700 (PDT)
X-Originating-IP: [162.243.96.244]
In-Reply-To: <87zho6ozab.fsf@HIDDEN>
References: <87zho6ozab.fsf@HIDDEN>
From: Nick Bowler <nbowler@HIDDEN>
Date: Wed, 1 May 2019 14:28:01 -0400
Message-ID: <CADyTPEzSTA=EmycitAXcsJrpj68L145+OkRZKsMBLrUKmqc2cA@HIDDEN>
Subject: Re: bug#35526: misleading documentation about flag variable ordering
To: Daniel Kahn Gillmor <dkg@HIDDEN>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Spam-Score: 0.0 (/)
X-Debbugs-Envelope-To: 35526
Cc: 35526 <at> debbugs.gnu.org
X-BeenThere: debbugs-submit <at> debbugs.gnu.org
X-Mailman-Version: 2.1.18
Precedence: list
List-Id: <debbugs-submit.debbugs.gnu.org>
List-Unsubscribe: <https://debbugs.gnu.org/cgi-bin/mailman/options/debbugs-submit>, 
 <mailto:debbugs-submit-request <at> debbugs.gnu.org?subject=unsubscribe>
List-Archive: <https://debbugs.gnu.org/cgi-bin/mailman/private/debbugs-submit/>
List-Post: <mailto:debbugs-submit <at> debbugs.gnu.org>
List-Help: <mailto:debbugs-submit-request <at> debbugs.gnu.org?subject=help>
List-Subscribe: <https://debbugs.gnu.org/cgi-bin/mailman/listinfo/debbugs-submit>, 
 <mailto:debbugs-submit-request <at> debbugs.gnu.org?subject=subscribe>
Errors-To: debbugs-submit-bounces <at> debbugs.gnu.org
Sender: "Debbugs-submit" <debbugs-submit-bounces <at> debbugs.gnu.org>
X-Spam-Score: -1.0 (-)

On 5/1/19, Daniel Kahn Gillmor <dkg@HIDDEN> wrote:
> https://www.gnu.org/software/automake/manual/automake.html#Flag-Variables=
-Ordering
> says:
>
>     The reason =E2=80=98$(CPPFLAGS)=E2=80=99 appears after =E2=80=98$(AM_=
CPPFLAGS)=E2=80=99 or
>     =E2=80=98$(mumble_CPPFLAGS)=E2=80=99 in the compile command is that u=
sers should
>     always have the last say.
>
> The implication here is that for any of the *FLAGS variables, later
> options are inherently more effective than earlier options.
>
> This is not the case universally.  For example -Wl,--as-needed is more
> effective if it shows up earlier in the command line.  (see
> https://bugs.debian.org/347650 for a libtool-related problem for that
> kind of ordering/re-ordering)

It's still mostly true, and it really is more about turning off options
that may be turned on by the package but the user does not want.  Even
in the case of --as-needed, if the package had AM_LDFLAGS =3D -Wl,--as-need=
ed
the user could (in principle) cancel it with LDFLAGS =3D -Wl,--no-as-needed=
,
since the user flags appear later.  If these were reversed then the
package option would override anything the user tried to do.

But it is true that this is not universal.  Not every compiler option
has a way to cancel its effect later on the command line.  In the case
of CPPFLAGS, -I options are an example where later options are in some
sense "less effective" than earlier options.

But on the other hand, -D options are commonly placed in CPPFLAGS and
in that case their effects can be canceled and/or changed by later
options.

Since all the user-provided flags are lumped together in a single
variable they have to go _somewhere_ as a unit, and convention puts them
after the corresponding package-set flags, so compilation commands look
something like:

  cc <package-cppflags> <user-cppflags> <package-cflags> <user-cflags> \
      <operational-switches> <files>

and linking (when the C compiler is used for linking) looks like:

  cc <package-cflags> <user-cflags> <package-ldflags> <user-ldflags> \
      <operational-switches> <objects-and-libraries>

(Note that the convention puts LDFLAGS before libraries so things
like LDFLAGS=3D-Wl,--as-needed _should_ work as expected, libtool
issues notwithstanding).

Obviously this scheme is not perfect in every possible scenario, but
the only way to handle every possible scenario is probably to have the
user to write all the compiler commands manually, in which case there
is no point in having a build system.

> It would be good if the documentation could avoid implying something
> that isn't the case, because that dubious suggestion casts doubt on the
> rest of the documentation (or on the user's understanding of the rest of
> the buildsystem)

The manual can always be improved.  Do you have a suggestion for how to
write this paragraph to make it better?

Cheers,
  Nick




Information forwarded to bug-automake@HIDDEN:
bug#35526; Package automake. Full text available.

Message received at submit <at> debbugs.gnu.org:


Received: (at submit) by debbugs.gnu.org; 1 May 2019 17:33:37 +0000
From debbugs-submit-bounces <at> debbugs.gnu.org Wed May 01 13:33:37 2019
Received: from localhost ([127.0.0.1]:44805 helo=debbugs.gnu.org)
	by debbugs.gnu.org with esmtp (Exim 4.84_2)
	(envelope-from <debbugs-submit-bounces <at> debbugs.gnu.org>)
	id 1hLt6v-0002Qu-52
	for submit <at> debbugs.gnu.org; Wed, 01 May 2019 13:33:37 -0400
Received: from eggs.gnu.org ([209.51.188.92]:51268)
 by debbugs.gnu.org with esmtp (Exim 4.84_2)
 (envelope-from <dkg@HIDDEN>) id 1hLt6s-0002Qg-I4
 for submit <at> debbugs.gnu.org; Wed, 01 May 2019 13:33:35 -0400
Received: from lists.gnu.org ([209.51.188.17]:51891)
 by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32)
 (Exim 4.71) (envelope-from <dkg@HIDDEN>)
 id 1hLt6m-0000TX-OB
 for submit <at> debbugs.gnu.org; Wed, 01 May 2019 13:33:29 -0400
Received: from eggs.gnu.org ([209.51.188.92]:37415)
 by lists.gnu.org with esmtp (Exim 4.71)
 (envelope-from <dkg@HIDDEN>) id 1hLt6l-0002Sx-Jm
 for bug-automake@HIDDEN; Wed, 01 May 2019 13:33:28 -0400
X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on eggs.gnu.org
X-Spam-Level: 
X-Spam-Status: No, score=0.0 required=5.0 tests=BAYES_40,URIBL_BLOCKED
 autolearn=disabled version=3.3.2
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
 (envelope-from <dkg@HIDDEN>) id 1hLt6j-0000OY-N7
 for bug-automake@HIDDEN; Wed, 01 May 2019 13:33:27 -0400
Received: from che.mayfirst.org ([2001:470:1:116::7]:32938)
 by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32)
 (Exim 4.71) (envelope-from <dkg@HIDDEN>)
 id 1hLt6h-0000Fh-49
 for bug-automake@HIDDEN; Wed, 01 May 2019 13:33:23 -0400
DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/simple; 
 d=fifthhorseman.net; i=@fifthhorseman.net; q=dns/txt; 
 s=2019; t=1556731999; h=from : to : subject : date : 
 message-id : mime-version : content-type : from; 
 bh=EEadGMITB4KRBvf/Gd9rrQyWznr2anJ6EExhKaJHys8=; 
 b=TEand1458fNMB522huPH+l6FLBBSHAAX/lnE4rSUKiHaQ5LqNVEKmKN/
 rkmsmKD9mKjANxl40lynY7V0OWwFCg==
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=fifthhorseman.net; 
 i=@fifthhorseman.net; q=dns/txt; s=2019rsa; t=1556731999; 
 h=from : to : subject : date : message-id : mime-version 
 : content-type : from; 
 bh=EEadGMITB4KRBvf/Gd9rrQyWznr2anJ6EExhKaJHys8=; 
 b=Fu67tQ6NtdIpORwzEABve1ce8K8SxRL91qmr1WvTSyO2kJWCd5DLgOP2
 TUX5fYb9FUS+71pi08SGA3KUaK0B1I+aklJzSwLGTJrBYrn75Q3LpxUvGj
 McWa9JP9hFBQyAu/+B7FiuRwfJgmXzw+GZaAHZIx50ySBa0z1UgGdm4SOU
 byECqRUISFv3H7xbA04XrsUkR84g9abxzlvkmLZEXcYX97K521I5kczMiK
 OE4QoXC4hBlEu7S2XXwFySbGY09RFy5crNfs7ekK4AqFg0oyt29IVRCZPW
 kykHRNnx9v/uvaYKliHRG5Xc71uTC3YuhWIEYLFAzVk3UkCop5KctA==
Received: from fifthhorseman.net (unknown [38.109.115.130])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (No client certificate requested)
 by che.mayfirst.org (Postfix) with ESMTPSA id 59B74F99E
 for <bug-automake@HIDDEN>; Wed,  1 May 2019 13:33:18 -0400 (EDT)
Received: by fifthhorseman.net (Postfix, from userid 1000)
 id 9FB7C2058F; Wed,  1 May 2019 13:33:16 -0400 (EDT)
From: Daniel Kahn Gillmor <dkg@HIDDEN>
To: bug-automake@HIDDEN
Subject: misleading documentation about flag variable ordering
Autocrypt: addr=dkg@HIDDEN; prefer-encrypt=mutual; keydata=
 mDMEXEK/AhYJKwYBBAHaRw8BAQdAr/gSROcn+6m8ijTN0DV9AahoHGafy52RRkhCZVwxhEe0K0Rh
 bmllbCBLYWhuIEdpbGxtb3IgPGRrZ0BmaWZ0aGhvcnNlbWFuLm5ldD6ImQQTFggAQQIbAQUJA8Jn
 AAULCQgHAgYVCgkICwIEFgIDAQIeAQIXgBYhBMS8Lds4zOlkhevpwvIGkReQOOXGBQJcQsbzAhkB
 AAoJEPIGkReQOOXG4fkBAO1joRxqAZY57PjdzGieXLpluk9RkWa3ufkt3YUVEpH/AP9c+pgIxtyW
 +FwMQRjlqljuj8amdN4zuEqaCy4hhz/1DbgzBFxCv4sWCSsGAQQB2kcPAQEHQERSZxSPmgtdw6nN
 u7uxY7bzb9TnPrGAOp9kClBLRwGfiPUEGBYIACYWIQTEvC3bOMzpZIXr6cLyBpEXkDjlxgUCXEK/
 iwIbAgUJAeEzgACBCRDyBpEXkDjlxnYgBBkWCAAdFiEEyQ5tNiAKG5IqFQnndhgZZSmuX/gFAlxC
 v4sACgkQdhgZZSmuX/iVWgD/fCU4ONzgy8w8UCHGmrmIZfDvdhg512NIBfx+Mz9ls5kA/Rq97vz4
 z48MFuBdCuu0W/fVqVjnY7LN5n+CQJwGC0MIA7QA/RyY7Sz2gFIOcrns0RpoHr+3WI+won3xCD8+
 sVXSHZvCAP98HCjDnw/b0lGuCR7coTXKLIM44/LFWgXAdZjm1wjODbg4BFxCv50SCisGAQQBl1UB
 BQEBB0BG4iXnHX/fs35NWKMWQTQoRI7oiAUt0wJHFFJbomxXbAMBCAeIfgQYFggAJhYhBMS8Lds4
 zOlkhevpwvIGkReQOOXGBQJcQr+dAhsMBQkB4TOAAAoJEPIGkReQOOXGe/cBAPlek5d9xzcXUn/D
 kY6jKmxe26CTws3ZkbK6Aa5Ey/qKAP0VuPQSCRxA7RKfcB/XrEphfUFkraL06Xn/xGwJ+D0hCw==
Date: Wed, 01 May 2019 13:33:16 -0400
Message-ID: <87zho6ozab.fsf@HIDDEN>
MIME-Version: 1.0
Content-Type: multipart/signed; boundary="=-=-=";
 micalg=pgp-sha512; protocol="application/pgp-signature"
X-detected-operating-system: by eggs.gnu.org: Genre and OS details not
 recognized.
X-Received-From: 2001:470:1:116::7
X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6.x
X-Spam-Score: -1.3 (-)
X-Debbugs-Envelope-To: submit
X-BeenThere: debbugs-submit <at> debbugs.gnu.org
X-Mailman-Version: 2.1.18
Precedence: list
List-Id: <debbugs-submit.debbugs.gnu.org>
List-Unsubscribe: <https://debbugs.gnu.org/cgi-bin/mailman/options/debbugs-submit>, 
 <mailto:debbugs-submit-request <at> debbugs.gnu.org?subject=unsubscribe>
List-Archive: <https://debbugs.gnu.org/cgi-bin/mailman/private/debbugs-submit/>
List-Post: <mailto:debbugs-submit <at> debbugs.gnu.org>
List-Help: <mailto:debbugs-submit-request <at> debbugs.gnu.org?subject=help>
List-Subscribe: <https://debbugs.gnu.org/cgi-bin/mailman/listinfo/debbugs-submit>, 
 <mailto:debbugs-submit-request <at> debbugs.gnu.org?subject=subscribe>
Errors-To: debbugs-submit-bounces <at> debbugs.gnu.org
Sender: "Debbugs-submit" <debbugs-submit-bounces <at> debbugs.gnu.org>
X-Spam-Score: -2.3 (--)

--=-=-=
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: quoted-printable

https://www.gnu.org/software/automake/manual/automake.html#Flag-Variables-O=
rdering

says:

    The reason =E2=80=98$(CPPFLAGS)=E2=80=99 appears after =E2=80=98$(AM_CP=
PFLAGS)=E2=80=99 or
    =E2=80=98$(mumble_CPPFLAGS)=E2=80=99 in the compile command is that use=
rs should
    always have the last say.

The implication here is that for any of the *FLAGS variables, later
options are inherently more effective than earlier options.

This is not the case universally.  For example -Wl,--as-needed is more
effective if it shows up earlier in the command line.  (see
https://bugs.debian.org/347650 for a libtool-related problem for that
kind of ordering/re-ordering)

It would be good if the documentation could avoid implying something
that isn't the case, because that dubious suggestion casts doubt on the
rest of the documentation (or on the user's understanding of the rest of
the buildsystem)

thanks for maintaining automake!

    --dkg

--=-=-=
Content-Type: application/pgp-signature; name="signature.asc"

-----BEGIN PGP SIGNATURE-----

iHUEARYKAB0WIQTJDm02IAobkioVCed2GBllKa5f+AUCXMnYXAAKCRB2GBllKa5f
+EN/AP9qJghwHrH97nFnNrn3aZkdzdgxmWQ/jwNa6ewpGLr8cwD9GypJ+1/Jyueb
nIlUkA2p/eDshKnpy9+LYj5PmdIOfQQ=
=8tda
-----END PGP SIGNATURE-----
--=-=-=--




Acknowledgement sent to Daniel Kahn Gillmor <dkg@HIDDEN>:
New bug report received and forwarded. Copy sent to bug-automake@HIDDEN. Full text available.
Report forwarded to bug-automake@HIDDEN:
bug#35526; Package automake. Full text available.
Please note: This is a static page, with minimal formatting, updated once a day.
Click here to see this page with the latest information and nicer formatting.
Last modified: Mon, 25 Nov 2019 12:00:02 UTC

GNU bug tracking system
Copyright (C) 1999 Darren O. Benham, 1997 nCipher Corporation Ltd, 1994-97 Ian Jackson.