comparisons..

[Andrew Morton]

"Martin v. Loewis" wrote:
> 
> > Drat.  I've wasted your time.  Sorry.
> >
> > pwold011:/home/morton> gcc -v
> > Reading specs from /usr/lib/gcc-lib/i686-unknown-linux/2.7.2.3/specs
> > gcc version 2.7.2.3
> >
> > Any chance of a backport? :)
> 
> mira% kgcc -v
> Reading specs from /usr/lib/gcc-lib/i386-redhat-linux/2.7.2.3/specs
> gcc version 2.7.2.3
> mira% kgcc -S -W a.c
> a.c: In function `y':
> a.c:5: warning: unsigned value < 0 is always 0
> 
> What do you get?

Enlightenment :)

The kernel uses -Wall, and this particular warning is not enabled with
-Wall.

Unfortunately using `-W' in the kernel makefiles generates a truckload
of warnings.  Is there a way of unbundling the `if (unsigned < 0)'
warning with a standalone flag?  Like -Wnegative-unsigned?   It appears
not.

The whole reason I brought this up is that someone found an `if
(unsigned < 0)' bug today.  Made my ears prick up.

A useful exercise would be to compile the kernel with `-W' and filter
out all the noise.   I'll do that tonight.

Thanks again.