Re: [PATCH v2 00/11] getting back -Wmaybe-uninitialized

[Linus Torvalds <torvalds@linux-foundation.org>]

On Thu, Nov 10, 2016 at 8:44 AM, Arnd Bergmann <arnd@arndb.de> wrote:
>
> Please merge these directly if you are happy with the result.

I will take this.

I do see two warnings, but they both seem to be valid and recent,
though, so I have no issues with the spurious cases.

Warning #1:

  sound/soc/qcom/lpass-platform.c: In function =E2=80=98lpass_platform_pcmo=
ps_open=E2=80=99:
  sound/soc/qcom/lpass-platform.c:83:29: warning: =E2=80=98dma_ch=E2=80=99 =
may be used
uninitialized in this function [-Wmaybe-uninitialized]
    drvdata->substream[dma_ch] =3D substream;
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~

and 'dma_ch' usage there really is crazy and wrong. Broken by
022d00ee0b55 ("ASoC: lpass-platform: Fix broken pcm data usage")

Warning #2 is not a real bug, but it's reasonable that gcc doesn't
know that storage_bytes (chip->read_size) has to be 2/4. Again,
introduced recently by commit 231147ee77f3 ("iio: maxim_thermocouple:
Align 16 bit big endian value of raw reads"), so you didn't see it.

  drivers/iio/temperature/maxim_thermocouple.c: In function
=E2=80=98maxim_thermocouple_read_raw=E2=80=99:
  drivers/iio/temperature/maxim_thermocouple.c:141:5: warning: =E2=80=98ret=
=E2=80=99
may be used uninitialized in this function [-Wmaybe-uninitialized]
    if (ret)
       ^
  drivers/iio/temperature/maxim_thermocouple.c:128:6: note: =E2=80=98ret=E2=
=80=99 was
declared here
    int ret;
        ^~~

and I guess that code can just initialize 'ret' to '-EINVAL' or
something to just make the theoretical "somehow we had a wrong
chip->read_size" case error out cleanly.

                Linus