Re: [PATCH] arch: configuration, deleting 'CONFIG_BUG' since always need it.

Geert Uytterhoeven
2013-05-23T09:12:56Z

On Thu, May 23, 2013 at 11:05 AM, Russell King - ARM Linux
<linux@arm.linux.org.uk> wrote:
> On Thu, May 23, 2013 at 10:40:29AM +0200, Geert Uytterhoeven wrote:
>> On Thu, May 23, 2013 at 9:57 AM, Chen Gang <gang.chen@asianux.com> wrote:
>> > -config BUG
>> > - bool "BUG() support" if EXPERT
>> > - default y
>> > - help
>> > - Disabling this option eliminates support for BUG and WARN, reducing
>> > - the size of your kernel image and potentially quietly ignoring
>> > - numerous fatal conditions. You should only consider disabling this
>> > - option for embedded systems with no facilities for reporting errors.
>> > - Just say Y.
>>
>> ... It's about reducing memory size on devices where you can't show bug or
>> warning messages.
>
> And turning off CONFIG_BUG causes lots of warning messages at compile time
> about functions which are returning nothing which shouldn't.
>
> The problem is: trying to fix that _will_ mean the result is a larger
> kernel than if you just do the usual arch-implemented thing of placing
> an defined faulting instruction at the BUG() site - which defeats the
> purpose of turning off CONFIG_BUG.

Is __builtin_unreachable() working well these days?

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