Re: kbuild: fixing the select problem

From: Geert Uytterhoeven
Date: Thu May 06 2010 - 02:47:49 EST


On Wed, May 5, 2010 at 23:49, James Bottomley
<James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> wrote:
> [Sam: I know you don't maintain kbuild anymore, but since you have the
> most experience, if you could find time to comment, I'd be grateful]
>
> The select problem is that the kbuild select directive will turn a
> symbol on without reference to its dependencies. ÂThis, in turn, means
> that either selected symbols must select their dependencies, or that
> people using select have to be aware of the selected symbol's dependency
> and build those dependencies into their symbol (leading to duplication
> and the possibility of getting the dependencies out of sync). ÂWe use
> select for the scsi transport classes, so we run into this problem in
> SCSI quite a lot.
>
> I think the correct fix is to make a symbol that selects another symbol
> automatically inherit all of the selected symbol's dependencies.

What if there's a good reason the selected symbol has this dependency?
E.g. it depends on a critical feature not available? Like CONFIG_HAS_IOMEM?

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/