Re: [PATCH] b43: shut up clang -Wuninitialized variable warning

From: Kalle Valo
Date: Thu Apr 04 2019 - 06:14:27 EST


Arnd Bergmann <arnd@xxxxxxxx> wrote:

> Clang warns about what is clearly a case of passing an uninitalized
> variable into a static function:
>
> drivers/net/wireless/broadcom/b43/phy_lp.c:1852:23: error: variable 'gains' is uninitialized when used here
> [-Werror,-Wuninitialized]
> lpphy_papd_cal(dev, gains, 0, 1, 30);
> ^~~~~
> drivers/net/wireless/broadcom/b43/phy_lp.c:1838:2: note: variable 'gains' is declared here
> struct lpphy_tx_gains gains, oldgains;
> ^
> 1 error generated.
>
> However, this function is empty, and its arguments are never evaluated,
> so gcc in contrast does not warn here. Both compilers behave in a
> reasonable way as far as I can tell, so we should change the code
> to avoid the warning everywhere.
>
> We could just eliminate the lpphy_papd_cal() function entirely,
> given that it has had the TODO comment in it for 10 years now
> and is rather unlikely to ever get done. I'm doing a simpler
> change here, and just pass the 'oldgains' variable in that has
> been initialized, based on the guess that this is what was
> originally meant.
>
> Fixes: 2c0d6100da3e ("b43: LP-PHY: Begin implementing calibration & software RFKILL support")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
> Acked-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx>
> Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx>

Patch applied to wireless-drivers-next.git, thanks.

d825db346270 b43: shut up clang -Wuninitialized variable warning

--
https://patchwork.kernel.org/patch/10865933/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches