Re: [PATCH 01/10] Add support for GCC-4.5's __builtin_unreachable() to compiler.h

From: Geert Uytterhoeven
Date: Sat Sep 12 2009 - 03:22:48 EST


On Fri, Sep 11, 2009 at 17:58, David Daney<ddaney@xxxxxxxxxxxxxxxxxx> wrote:
> Michael Buesch wrote:
>>
>> On Friday 11 September 2009 01:56:42 David Daney wrote:
>>>
>>> +/* Unreachable code */
>>> +#ifndef unreachable
>>> +# define unreachable() do { for (;;) ; } while (0)
>>> +#endif
>>
>> # define unreachable() do { } while (1)
>>
>> ? :)
>
> Clearly I was not thinking clearly when I wrote that part. ÂRTH noted the
> same thing. ÂI will fix it.

However, people are so used to seeing the `do { } while (0)' idiom,
that they might miss
there's a `1' here, not a `0'.

So perhaps it's better to use plain `for (;;)' for infinite loops?

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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