Re: Issue with BUG() in asm-gemeric/bug.h if CONFIG_BUG=n

From: Geert Uytterhoeven
Date: Mon Sep 30 2013 - 15:03:35 EST


On Mon, Sep 30, 2013 at 7:45 PM, David Daney <ddaney.cavm@xxxxxxxxx> wrote:
>> What about using __builtin_unreachable when we can but turn off warnings
>> and use do{}while(0) when __builtin_unreachable does not exist? This seems
>> the both worlds. Newer compilers produce better code with unreachable
>> anyways.
>>
>
> Simply not true.
>
> do{}while(0) is a NOP it is no more useful than an ';' statement. It
> doesn't serve as a magic uninitialized variable hiding mechanism.

You missed the "turn off warnings" part of the "and".

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
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