Re: Warnings on global symbols accessed only from assembly code

["Ahmed S. Darwish" <darwish.07@gmail.com>]

On Thu, Feb 11, 2010 at 05:06:56PM -0800, Christopher Li wrote:
> On Thu, Feb 11, 2010 at 4:00 PM, Ahmed S. Darwish <darwish.07@gmail.com> wrote:
> [..]
> > The reason is that a declaration for such methods - which are usually
> > bootstrap ones - can given the false impression of being used by some
> > C code 'somewhere'.
> 
> Sparse does not care about who call those function, C code or asm code.
> Sparse don't not actually link the program so it can't know this symbol is
> actually externally used or not.
> 
> Personally, I don't see why you can't declare those functions even
> if they are called from asm.
>

Yes, the declarations are doable of course, but they'll be for-the-sake-
-of-sparse thing.

The case I faced was kernel's main entrance C method which should only be
jumped to from bootstrap asm code. I think a declaration in such case will
only give bogus function usage impressions.

> > Unfortunately the current `-Wno-decl' solution is a bit extreme: it
> > turns off a very useful sparse feature (by design).
> 
> Right, the problem is that sparse can't tell which functions are used in
> asm files and only skip warning on those.
>

Would proposing an __attribute__ for such case be accepted in concept?

> Chris

Thanks a lot

-- 
Darwish
http://darwish.07.googlepages.com