Gentoo Archives: gentoo-dev

From: Vaeth <vaeth@××××××××××××××××××××××××.de>
To: gentoo-dev@l.g.o
Subject: [gentoo-dev] Re: [gentoo-dev-announce] debug USE flag misuse
Date: Thu, 01 Jul 2010 21:45:35
In Reply to: [gentoo-dev] Re: [gentoo-dev-announce] debug USE flag misuse by Vaeth
Ryan Hill <dirtyepic@g.o> wrote:
> Upstream is free to use whatever CFLAGS they see fit, as long as the > user has the option of disabling them. This is simply done by appending > the user's CFLAGS to those of the build system.
Since it is obvious that by _appending_ only the user's CFLAGS to your own, you do not give him the option of disabling your own, the more natural way to do this is to make it configurable in the build system, e.g. by a ./configure option.
> But this has nothing to do with USE flags.
The usual way in gentoo to pass upstream's ./configure options to the user is via USE flags.
> USE flags control package options
And in a case as the described, the CFLAGS become part of the package options (at least what upstream considers as package options).
> The way to control compiler flags in Gentoo is CFLAGS.
CFLAGS in Gentoo are the way to pass CFLAGS to the build system. Nothing more, nothing less. You want to make it the _only_ way to control compiler flags. Since Gentoo is lacking any other mechanism allowing an ebuild author or upstream to set default CFLAGS (binary distributions do not need such things, because the packager should compile the package with the appropriate flags anyway), this would mean _in practice_: Either upstreams forces its flags upon the user, or most users will *not* build the package according to the package authors' suggestions (and most will probably not even realize this). You cannot seriously believe that one of these possibilities is better than to make the things transparent to the user and to give him the choice _in practice_ by means of a USE flag.
> If --enable-debug does more than that then having a debug USE flag is > perfectly fine. I don't have a problem with --enable-debug adding -g > as well as (eg.) enabling assertions
This is one of the things which are happening. More precisely, not disabling assertions by *not* adding -DNDEBUG (and e.g. not breaking code by not adding -flto with the -g). Admittedly, it is not overly complex what USE=debug does, but - well, it enables the only debugging support which is available which in this case is all related with CFLAGS in some way or another. Best Regards Martin Väth


Subject Author
[gentoo-dev] Re: [gentoo-dev-announce] debug USE flag misuse Vaeth <vaeth@××××××××××××××××××××××××.de>
[gentoo-dev] Re: [gentoo-dev-announce] debug USE flag misuse Ryan Hill <dirtyepic@g.o>