Re: [PATCH] b43: Fix sparse warnings

[Pavel Roskin <proski@gnu.org>]

On Fri, 2009-08-14 at 22:15 +0200, Michael Buesch wrote:

> > -			b43_phy_mask(dev, 0x048A, (u16)~0x8000);
> > +			b43_phy_mask(dev, 0x048A, (u16)(~0x8000 & 0xFFFF));
> 
> Uh come on...
> The u16 cast already is stupid as hell, but this is becoming braindead.
> The code is perfectly fine. Sparse should instead provide an option to disable
> this fragile check.

There are cases where we want to know that a constant was truncated.  In
fact, in most cases it's a useful warning.

In this case, we intuitively expect that it's OK to cast a result of a
bitwise operation to its original type, as if it was never promoted.
But sparse will need to have a special exception for this case.

I would just use 0x7fff here.

-- 
Regards,
Pavel Roskin