Re: [PATCH v2] x86/cpu: fix prototype warning

From: Borislav Petkov
Date: Thu Nov 08 2018 - 12:22:37 EST


On Thu, Nov 08, 2018 at 03:47:32PM +0000, Michael Matz wrote:
> What tglx said. If you don't intend such functions to be called
> from other units make them static, if you do intend them to be callable
> declare the properly.
>
> [There's also one subtle issue with argument promotions. prototypeless
> functions are called as if they are declared "int name()" that is
> default argument promotions take place (float->double, {char,short}->int),
> which won't happen with prototypes, and argument type conversions won't
> take place (as no parameter types are known). This might lead to
> different values between calling a prototyped and a prototype-less
> function arriving at the function even though the call expression looked
> the same]

Eww, that's yucky.

Ok, so we should enalbe this warning by default then. And doing that in
the main Makefile gives ~1400 warnings on an allmodconfig build.

Yi Wang, I guess you have a long road in front of you. :-)

Thx.

--
Regards/Gruss,
Boris.

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