ugly warnings with likely/unlikely

ugly warnings with likely/unlikely

[Oliver Neukum]

Hi,

if (likely(stru->pointer))

results in an ugly warning about using pointer as int.
Is there something that could be done against that ?

	Regards
		Oliver

Re: ugly warnings with likely/unlikely

[Oliver Neukum]

On Sunday 13 January 2002 16:07, Alan Cox wrote:
> > if (likely(stru->pointer))
> >
> > results in an ugly warning about using pointer as int.
> > Is there something that could be done against that ?
>
> 	if (likely(stru->pointer == NULL))
>
> Perhaps ?

That works. But it's so much work to type it.

	Regards
		Oliver

Re: ugly warnings with likely/unlikely

[Alan Cox]

> if (likely(stru->pointer))
> 
> results in an ugly warning about using pointer as int.
> Is there something that could be done against that ?

	if (likely(stru->pointer == NULL))

Perhaps ?

Re: ugly warnings with likely/unlikely

[Andi Kleen]

520047054719-0001@t-online.de (Oliver Neukum) writes:

> Hi,
> 
> if (likely(stru->pointer))
> 
> results in an ugly warning about using pointer as int.
> Is there something that could be done against that ?

Just use 

if (!stru->pointer) { 
	...
}

instead. gcc and a lot of other compilers predict all pointer tests
against NULL as unlikely, unless you override that.

-Andi (who is a bit worried about the unlikelies multiplicating like rabbits)
 

Re: ugly warnings with likely/unlikely

[Robert Love]

On Sun, 2002-01-13 at 12:27, Andi Kleen wrote:

> -Andi (who is a bit worried about the unlikelies multiplicating like rabbits)

Indeed.  People need to realize unlikely is not a free ride.

	Robert Love

Re: ugly warnings with likely/unlikely

[Andrew Morton]

Alan Cox wrote:
> 
> > if (likely(stru->pointer))
> >
> > results in an ugly warning about using pointer as int.
> > Is there something that could be done against that ?
> 
>         if (likely(stru->pointer == NULL))
> 

-#define likely(x)       __builtin_expect((x),1)
-#define unlikely(x)     __builtin_expect((x),0)
+#define likely(x)       __builtin_expect((x)!=0,1)
+#define unlikely(x)     __builtin_expect((x)!=0,0)

?