Re: [PATCH] qed: Fix -Wmaybe-uninitialized false positive

[David Miller]

From: Arnd Bergmann <arnd@xxxxxxxx>
Date: Mon, 17 Jun 2019 15:04:49 +0200

> A previous attempt to shut up the uninitialized variable use
> warning was apparently insufficient. When CONFIG_PROFILE_ANNOTATED_BRANCHES
> is set, gcc-8 still warns, because the unlikely() check in DP_NOTICE()
> causes it to no longer track the state of all variables correctly:
> 
> drivers/net/ethernet/qlogic/qed/qed_dev.c: In function 'qed_llh_set_ppfid_affinity':
> drivers/net/ethernet/qlogic/qed/qed_dev.c:798:47: error: 'abs_ppfid' may be used uninitialized in this function [-Werror=maybe-uninitialized]
>   addr = NIG_REG_PPF_TO_ENGINE_SEL + abs_ppfid * 0x4;
>                                      ~~~~~~~~~~^~~~~
> 
> This is not a nice workaround, but always initializing the output from
> qed_llh_abs_ppfid() at least shuts up the false positive reliably.
> 
> Fixes: 79284adeb99e ("qed: Add llh ppfid interface and 100g support for offload protocols")
> Fixes: 8e2ea3ea9625 ("qed: Fix static checker warning")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Applied to net-next.