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

Geert Uytterhoeven
2019-06-13T20:13:26Z

Hi Charles,

On Thu, Jun 13, 2019 at 8:09 PM Charles <18oliveira.charles@gmail.com> 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 ‘sci_dma_rx_submit’:
> ./include/linux/spinlock.h:288:3: warning: ‘flags’ may be used
> uninitialized in this function [-Wmaybe-uninitialized]
> _raw_spin_unlock_irqrestore(lock, flags); \
> ^~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/tty/serial/sh-sci.c:1353:16: note: ‘flags’ was declared here
> unsigned long flags;
> ^~~~~
>
> Signed-off-by: Charles Oliveira <18oliveira.charles@gmail.com>

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@linux-m68k.org

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