Messages in this thread | | | Date | Wed, 5 Jul 2006 16:35:30 -0700 | From | Andrew Morton <> | Subject | Re: [PATCH] genirq: ARM dyntick cleanup |
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On Wed, 5 Jul 2006 16:24:25 -0700 "Randy.Dunlap" <rdunlap@xenotime.net> wrote:
> On Mon, 03 Jul 2006 19:27:07 +0200 Arjan van de Ven wrote: > > > On Mon, 2006-07-03 at 10:13 -0700, Linus Torvalds wrote: > > > #ifndef xyzzy > > > #define zyzzy() /* empty */ > > > #endif > > > > > > > now if you write it as > > > > #define zyzzy() do { ; } while (0) > > > > it even works in a > > > > if (foo()) > > zyzzy(); > > bar(); > > > > scenario > > > > (I know you know that, just pointing that out before people copy your > > example :-) > > OK, I'll bite. What part of Linus's macro doesn't work. > I compiled your foo/zyzzy/bar example with both his "empty" > macro and the do-while macro. Same code produced both ways, > no compile warnings/errors. >
if (foo()) ;
will generate `warning: empty body in an if-statement' when compiled with -W.
We go round this loop regularly. Maybe someone should write it up. Meanwhile, use do{}while(0) and be happy and secure. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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