Re: "arm64: vdso: Substitute gettimeofday() with C implementation" breaks clang build

[Vincenzo Frascino]

Hi Qian,

On 25/06/2019 18:31, Qian Cai wrote:
> On Tue, 2019-06-25 at 18:00 +0100, Vincenzo Frascino wrote:
>> Hi Nick,
>>
>> On 25/06/2019 17:26, Nick Desaulniers wrote:
>>> On Tue, Jun 25, 2019 at 7:54 AM Vincenzo Frascino
>>> <vincenzo.frascino@xxxxxxx> wrote:
>>>>
>>>> Hi Qian,
>>>>
>>>> ...
>>>>
>>>>>
>>>>> but clang 7.0 is still use in many distros by default, so maybe this
>>>>> commit can
>>>>> be fixed by adding a conditional check to use "small" if clang version <
>>>>> 8.0.
>>>>>
>>>>
>>>> Could you please verify that the patch below works for you?
>>>
>>> Should it be checking against CONFIG_CLANG_VERSION, or better yet be
>>> using cc-option macro?
>>>
>>
>> This is what I did in my proposed patch, but I was surprised that clang-7
>> generates relocations that clang-8 does not.
>>
>> Â LDÂÂÂÂÂÂarch/arm64/kernel/vdso/vdso.so.dbg
>> Â VDSOCHK arch/arm64/kernel/vdso/vdso.so.dbg
>> 00000000000009d0 R_AARCH64_JUMP_SLOTÂÂ_mcount
>>
>> arch/arm64/kernel/vdso/vdso.so.dbg: dynamic relocations are not supported
>> make[1]: *** [arch/arm64/kernel/vdso/Makefile:59:
>> arch/arm64/kernel/vdso/vdso.so.dbg] Error 1
>> make: *** [arch/arm64/Makefile:180: vdso_prepare] Error 2
>>
>> This is the the result of the macro I introduced in lib/vdso/Makefile.
>>
>> And I just found out why. I forgot to add a "+" in the patch provided :)
>>
>> @Qian: Could you please retry with the one provided below?
>>
> 
> It works fine.
> 

Thanks for the confirmation, I will push the patch in a short while.

-- 
Regards,
Vincenzo