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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Fri, 10 Apr 2020 09:26:38 +0200
Message-ID: <CAMuHMdXnGdxqy6KUnJW69zwmNvHZhSpfXz0PancNrK91SMZp_g@mail.gmail.com>
Subject: Re: [RFC 0/6] Regressions for "imply" behavior change
To:     Saeed Mahameed <saeedm@mellanox.com>
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Hi Saeed,

On Fri, Apr 10, 2020 at 4:41 AM Saeed Mahameed <saeedm@mellanox.com> wrote:
> On Thu, 2020-04-09 at 11:41 +0300, Jani Nikula wrote:
> > For example, you have two graphics drivers, one builtin and another
> > module. Then you have backlight as a module. Using IS_REACHABLE(),
> > backlight would work in one driver, but not the other. I'm sure there
> > is
> > the oddball person who finds this desirable, but the overwhelming
> > majority would just make the deps such that either you make all of
> > them
> > modules, or also require backlight to be builtin.
>
> the previous imply semantics handled this by forcing backlight to be
> built-in, which worked nicely.

Which may have worked fine for backlight, but not for other symbols
with dependencies that are not always met.

=> Use "select" to enable something unconditionally, but this can only
    be used if the target's dependencies are met.
=> Use "imply" to enable an optional feature conditionally.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds