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To:     Sathyanarayanan Kuppuswamy 
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From:   Dave Hansen <dave.hansen@intel.com>
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On 9/12/22 19:44, Sathyanarayanan Kuppuswamy wrote:
>> and include the header (<linux/string.h> ?) for memchr_inv()?
> One of the previous headers includes linux/string.h (I am not sure which one).
> So why include it explicitly?

Because it's a best practice.  What happens is that you ride along on
the coat tails of another #include, someone sees that include is no
longer used and removes it.  Then, your code is busted on some weird
.config.

*OR*, the header itself changes and doesn't #include the dependency you
need.

I guess you can go add this advice to Documentation/ if it's not there
already somewhere.