[Buildroot] [PATCH 2/5] toolchain/external: fix wrapper by not passing conflicting flags

[Maxime Hadjinlian]

Hi all,

On Wed, Jan 8, 2014 at 7:01 PM, Yann E. MORIN <yann.morin.1998 at free.fr> wrote:
> Maxime, All,
>
> On 2014-01-08 16:57 +0100, Maxime Hadjinlian spake thusly:
>> On Wed, Jan 8, 2014 at 4:51 PM, Thomas Petazzoni
>> <thomas.petazzoni at free-electrons.com> wrote:
>> > Dear Maxime Hadjinlian,
>> Hi Thomas,
>> >
>> > On Wed, 8 Jan 2014 13:45:59 +0100, Maxime Hadjinlian wrote:
>> >
>> >> Shouldn't we change the different defconfig that exists ? At least the
>> >> RaspberryPi so it would sets an example (and maybe add something about
>> >> this in the manual ?)
>> >
>> > Why would the defconfig need some changes following this patch?
>> To set a visible example of settings the correct -march/mcpu/mtune options ?
>> Also, this would eliminate all the warnings that Yann saw while
>> building a kernel for the rpi, so it seems like a good candidate.
>
> There is nothing in that patch that impacts the configuration.
> There is no reason to change any defconfig to 'activate' this change.
>
> Rather, the config options BR2_GCC_TARGET_CPU, BR2_GCC_TARGET_ARCH, and
> BR2_GCC_TARGET_MTUNE, if any, are pased at the time we build the wrapper
> itself.
>
> Those options are set automatically when you choose, in the menuconfig,
> the type of CPU your target has. And since that will automatically set
> the BR2_GCC_TARGET_{ARCH,CPU,MTUNE} options, they are forcibly set.
>
> And since the raspberrypi_defconfig (as you use that as an example)
> already sets BR2_arm1176jzf_s=y, this will set BR2_GCC_TARGET_ARCH and
> BR2_GCC_TARGET_CPU.
>
> And this is exactly this situation this patch fixes: our options forcing
> the compiler flags, when some are already provided on the command line.
>
> So, there is no need (and no reason) to change any of our defconfigs to
> take advantage of this change.
>
> Regards,
> Yann E. MORIN.
My  bad,
I spoke too quickly and I misunderstood some information.

Thanks for your clarifications.
>
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