From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by finch.gentoo.org (Postfix) with ESMTPS id 788C8138334 for ; Wed, 22 May 2019 19:37:32 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id A5AE0E089E; Wed, 22 May 2019 19:37:30 +0000 (UTC) Received: from smtp.gentoo.org (smtp.gentoo.org [IPv6:2001:470:ea4a:1:5054:ff:fec7:86e4]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id 818EFE089E for ; Wed, 22 May 2019 19:37:30 +0000 (UTC) Received: from oystercatcher.gentoo.org (unknown [IPv6:2a01:4f8:202:4333:225:90ff:fed9:fc84]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.gentoo.org (Postfix) with ESMTPS id CDFF2344E45 for ; Wed, 22 May 2019 19:37:28 +0000 (UTC) Received: from localhost.localdomain (localhost [IPv6:::1]) by oystercatcher.gentoo.org (Postfix) with ESMTP id 720AA5EF for ; Wed, 22 May 2019 19:37:26 +0000 (UTC) From: "Göktürk Yüksek" To: gentoo-commits@lists.gentoo.org Content-Transfer-Encoding: 8bit Content-type: text/plain; charset=UTF-8 Reply-To: gentoo-dev@lists.gentoo.org, "Göktürk Yüksek" Message-ID: <1558553651.add4db87d50f4633dac12a21f5c0f98bc86cc5d6.gokturk@gentoo> Subject: [gentoo-commits] proj/devmanual:master commit in: general-concepts/use-flags/ X-VCS-Repository: proj/devmanual X-VCS-Files: general-concepts/use-flags/text.xml X-VCS-Directories: general-concepts/use-flags/ X-VCS-Committer: gokturk X-VCS-Committer-Name: Göktürk Yüksek X-VCS-Revision: add4db87d50f4633dac12a21f5c0f98bc86cc5d6 X-VCS-Branch: master Date: Wed, 22 May 2019 19:37:26 +0000 (UTC) Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-commits@lists.gentoo.org X-Auto-Response-Suppress: DR, RN, NRN, OOF, AutoReply X-Archives-Salt: 958d68b8-3610-4e42-99a5-171f0c81e748 X-Archives-Hash: ca994577d378bb523307b497f671d47a commit: add4db87d50f4633dac12a21f5c0f98bc86cc5d6 Author: Michał Górny gentoo org> AuthorDate: Sun Apr 14 09:44:18 2019 +0000 Commit: Göktürk Yüksek gentoo org> CommitDate: Wed May 22 19:34:11 2019 +0000 URL: https://gitweb.gentoo.org/proj/devmanual.git/commit/?id=add4db87 general-concepts/use-flags: Also note about flags controlling CFLAGS Signed-off-by: Michał Górny gentoo.org> general-concepts/use-flags/text.xml | 36 ++++++++++++++++++++++++++++++++++++ 1 file changed, 36 insertions(+) diff --git a/general-concepts/use-flags/text.xml b/general-concepts/use-flags/text.xml index c20e8d0..4d56d97 100644 --- a/general-concepts/use-flags/text.xml +++ b/general-concepts/use-flags/text.xml @@ -70,6 +70,42 @@ of flags to those programs or modules that have external dependencies and/or long build times. The rest of them should be built unconditionally instead, or controlled by a flag such as minimal.

+ +

+You should not introduce USE flags that merely manipulate CFLAGS, +FEATURES or similar variables configured directly by the user. Instead, +packages should avoid manipulating them at all, and let users set them directly. +Common mistakes include: +

+ +
    +
  1. + Using debug USE flag to force -O0 -g and disable + stripping. The correct purpose of debug flag is to control additional + debug code paths. The use of correct flags and features to preserve + debugging information is user's responsibility. +
    2. + +
  2. + Introducing lto flag to force -flto. This is something user + should set directly in flag varibles. +
    3. + +
  3. + Using CPU_FLAGS_* to control -m* options. Those flags are + intended to control code paths explicitly requiring specific CPU extensions, + e.g. separate assembly. Compiler-generated assembly should respect user's + -march choice. +
    4. +
+ +

+There might be corner cases where these rules do not apply. For example, a few +upstreams require users to use specific CFLAGS and reject bug reports +against builds using other values. In this case, it is customary to strip flags +by default and provide custom-cflags flag to allow users to force their +preferred flags. +