Re: [PATCH] serial: sh-sci: fix uninitialized variable warning

[Geert Uytterhoeven]

Hi Charles,

On Thu, Jun 13, 2019 at 8:09 PM Charles <18oliveira.charles@xxxxxxxxx> wrote:
> Avoid following compiler warning on uninitialized variable
>
> In file included from ./include/linux/rwsem.h:16:0,
>                  from ./include/linux/notifier.h:15,
>                  from ./include/linux/clk.h:17,
>                  from drivers/tty/serial/sh-sci.c:24:
> drivers/tty/serial/sh-sci.c: In function âsci_dma_rx_submitâ:
> ./include/linux/spinlock.h:288:3: warning: âflagsâ may be used
> uninitialized in this function [-Wmaybe-uninitialized]
>    _raw_spin_unlock_irqrestore(lock, flags); \
>    ^~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/tty/serial/sh-sci.c:1353:16: note: âflagsâ was declared here
>   unsigned long flags;
>                 ^~~~~
>
> Signed-off-by: Charles Oliveira <18oliveira.charles@xxxxxxxxx>

Thanks for your patch, but this is a false positive: the compiler is not
smart enough to realize that both initialization and use depend on
the same condition.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds