Re: [RFC][PATCH] introduce ptr_diff()

Bernd Petrovitsch
2010-08-19T16:05:05Z

On Fre, 2010-08-20 at 00:53 +0900, Namhyung Kim wrote:
> 2010-08-19 (목), 14:23 +0200, Andi Kleen:
> > IMHO it would be better to simply disable the warning in sparse instead
> > of uglying the code just to work around sparse bogosity. It doesnt' seem
> > to make much sense. A subtraction followed by a shift is not expensive.
[...]
> I'm curious who turns on that switch. -Wptr-subtraction-blows is turned
> off by default, I didn't use CF variable at build time and I could not
> find any reference of it in the source tree. Hmm..

sparse also gets gcc's parameters which include (usually) "-Wall". And
this activates it.
Adding -Wno-ptr-subtraction-blows to CHECKFLAGS should do the trick.

Bernd
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