Re: [PATCH v3 RESEND 1/2] arm: lib: xor-neon: remove unnecessary GCC < 4.6 warning

[Arnd Bergmann]

On Mon, Jan 18, 2021 at 12:28 PM Adrian Ratiu
<adrian.ratiu@xxxxxxxxxxxxx> wrote:
> On Mon, 18 Jan 2021, Arnd Bergmann <arnd@xxxxxxxxxx> wrote:
> > On Mon, Jan 18, 2021 at 11:56 AM Adrian Ratiu <adrian.ratiu@xxxxxxxxxxxxx> wrote:
>
> No, clang does not produce vectorized code by default, not even
> with the -ftree-vectorize flag explicitely added like in the next
> patch in this series (that flag is enabled by default in clang
> anyway, so no effect).
>
> Clang needs more investigation and testing because with additional
> code changes it can be "forced" to output vectorized code, but
> that is outside the scope of this series.
>
> If you think it's a good idea I can add a warning only for Clang
> which makes more sense than telling clang users to upgrade their
> GCC, since now Clang is officially supported. What do you think?

Yes, either a warning or a Kconfig check seems better to me than
just trying to build code that ends up not doing what it is meant to.

       Arnd