Re: [PATCH 06/12] s390: ctcm: fix ctcm_new_device error return code

Martin Schwidefsky
2019-04-10T16:00:07Z

On Mon, 8 Apr 2019 23:26:19 +0200
Arnd Bergmann <arnd@arndb.de> wrote:

> clang points out that the return code from this function is
> undefined for one of the error paths:
>
> ../drivers/s390/net/ctcm_main.c:1595:7: warning: variable 'result' is used uninitialized whenever 'if' condition is true
> [-Wsometimes-uninitialized]
> if (priv->channel[direction] == NULL) {
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ../drivers/s390/net/ctcm_main.c:1638:9: note: uninitialized use occurs here
> return result;
> ^~~~~~
> ../drivers/s390/net/ctcm_main.c:1595:3: note: remove the 'if' if its condition is always false
> if (priv->channel[direction] == NULL) {
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> ../drivers/s390/net/ctcm_main.c:1539:12: note: initialize the variable 'result' to silence this warning
> int result;
> ^
>
> Make it return -ENODEV here, as in the related failure cases.
> gcc has a known bug in underreporting some of these warnings
> when it has already eliminated the assignment of the return code
> based on some earlier optimization step.
>
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Added to our internal tree for Julian to pick up.

--
blue skies,
Martin.

"Reality continues to ruin my life." - Calvin.