On Tue, 2007-05-01 at 23:06 -0700, David Rientjes wrote: > On Wed, 2 May 2007, Rusty Russell wrote: > > > Adding this macro doesn't give us anything that simply saying > > "__attribute__((unused))" doesn't give. But it does add a layer of > > kernel-specific indirection. > > > > That's obviously true since we're defining __attribute_unused__ to be > __attribute__((unused)).
Hi David, I'm horribly familiar with this issue, BTW, so we don't need so many words 8) > The patched version makes this: > > int type __attribute_unused__ = 0; > > which definitely tells you that you're using a compiler attribute that > will be attached to that automatic. In your case: > > int type __unneeded = 0; > > doesn't say anything in this case. It doesn't resemble any attribute that > a programmer might be familiar with and begs the question of why we've > declared it if it's truly "unneeded"? Your version makes one wonder why they didn't use "__attribute__((unused))". Obviously the __attribute_unused__ macro exists for a reason, so they wonder what's the difference between that and the attribute? The answer: nothing. OTOH, your point about "__unneeded" is well taken. "__needed" and "__optional" perhaps? But their feature is *exactly* that the don't look like the gcc attributes, hence avoid their semantic screwage. > By the way, there are tons of these instances where __attribute__((used)) > needs to be added in driver code to suppress unreferenced warnings. Sure; historically we refactor around it. But warnings are now so commonplace few people care 8( Cheers, Rusty. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/