Re: [gentoo-dev] net-misc/strongswan USE_EXPAND

[Michał Górny]

Dnia 2015-06-23, o godz. 10:33:58
Jason Zaman <perfinion@g.o> napisał(a):

> On Tue, Jun 23, 2015 at 08:05:35AM +0200, Michał Górny wrote:
> > Then perhaps you go and fix the rules instead of ignoring them?
> >
> > But please also remember to provide the ability to describe those flags
> > per-package rather than globally, like they are done now. Would be good
> > to also avoid declaring them globally, like having >50 groups listed in
> > USE_EXPAND.
> >
> > When you're done with that, and get all package managers to support it
> > in a reasonably long stable version, then we can discuss about changing
> > the rules.
>
> I dont quite follow, the useflags are described in the packages
> metadata.xml, are not conflicting and are supported by everything.
>
> Is there a rule that everything that is USE_EXPAND'd is a global
> useflag? I see no such rule and I dont understand why it would even make
> sense. USE_EXPAND arnt useflags, it is just a variable to make useflags
> look nicer, they shouldnt all have to be global. What if one and only
> one package supports a specific video_card? Should that use-flag be made
> global?
>
> Adding use_expand's for foo_plugins makes things a lot easier to manage
> and understand tho. The only possible downside I can see is that there
> are a lot of entries in it, but we have a lot of useflags so thats hardly
> an issue.

It's not a rule, policy or magic. It's simply how Portage and some
other tools were designed.

You declare USE_EXPAND globally. If you declared it globally but all
flags were local, how would the global declaration really fit?

You describe those flags globally. Sure, there's probably no rule
prohibiting you from describing them via metadata.xml. However, most of
the tools will not expect USE_EXPAND flags to be declared locally. For
a quick test, see 'quse -D radeon' (vs 'quse -D video_cards_radeon').

The recommended way of setting USE_EXPAND flags was via global
make.conf variables so far. Sure, you can override them via
package.use, and even it in a convenient way for a few Portage versions
already, but still the global nature is strongly highlighted. Not that
I like setting anything via make.conf but it's not my decision to make.

-- 
Best regards,
Michał Górny
<http://dev.gentoo.org/~mgorny/>