Rasmus Villemoes [off-list ref] writes:

On 14/08/2020 17.14, Christian Lamparter wrote:

quoted

On 2020-08-14 13:39, Lee Jones wrote:

quoted

'ar9170_qmap' is used in some source files which include carl9170.h,
but not all of them.  Mark it as __maybe_unused to show that this is
not only okay, it's expected.

Fixes the following W=1 kernel build warning(s)

Is this W=1 really a "must" requirement? I find it strange having
__maybe_unused in header files as this "suggests" that the
definition is redundant.

In this case it seems one could replace the table lookup with a

static inline u8 ar9170_qmap(u8 idx) { return 3 - idx; }

gcc doesn't warn about unused static inline functions (or one would have
a million warnings to deal with). Just my $0.02.

Yeah, this is much better.

And I think that static variables should not even be in the header
files. Doesn't it mean that there's a local copy of the variable
everytime the .h file is included? Sure, in this case the overhead is
small (4 bytes per include) but still it's wrong. Having a static inline
function would solve that problem as well the compiler warning.

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