Re: sfc: an enumeration is not a bitmask

Michał Mirosław
2011-05-17T19:09:55Z

2011/5/17 Jeff Garzik <jgarzik@pobox.com>:
> 2011/5/17 David Miller <davem@davemloft.net>:
>> An enumeration is not a bitmask, instead it means one out of the set
>> of enumerated values will be used.
>
> It's a decade-old kernel practice to use 'enum' to define typed
> constants, preferred over  macros that convey no type information and
> disappear after cpp phase.
>
> So your assertion about enumerations is demonstrably not true, as it
> is often used in the kernel.  Call it enum abuse if you want, but it
> is consistent with code all over the kernel.
>
> That said, I agree that warnings should of course be addressed in some manner.

Old age of the mistake doesn't make it correct.

Disappearance of the #defines can be resolved by using enum of bit
positions (and maybe field lengths) and #define of (1 << bit_position)
if it is useful for something to remain after preprocessing.

Best Regards,
Michał Mirosław