Re: [Xenomai-core] [PATCH 2/3] x86-64: Work around gcc issues with populating syscall registers

[Jan Kiszka <jan.kiszka@domain.hid>]

[-- Attachment #1: Type: text/plain, Size: 1421 bytes --]

Philippe Gerum wrote:
> On Sun, 2009-07-19 at 17:23 +0200, Jan Kiszka wrote:
>> Gilles Chanteperdrix wrote:
>>> Jan Kiszka wrote:
>>>> gcc-4.1.3 of kubuntu has problem with proper syscall register
>>>> initialization in rt_task_shadow if TLS is enabled. But it is likely
>>>> that more compiler versions below 4.3 and more configuration variants
>>>> are affected.
>>>>
>>>> This patch installs a workaround for these gcc versions which places an
>>>> optimization barrier before the register variable setup. This forces gcc
>>>> to actually load the registers.
>>> I have tried the barrier with arm gcc, it does not work. However,
>>> marking the registered clobbered instead of the memory fixes arm gcc 4.3
>>> bug. So, I wonder, would not it make more sense to mark the registers as
>>> clobbered by the barrier instead of memory on x86 too?
>>>
>> Sounds reasonable. Will give it a try later.

Sounded reasonable - but didn't work. So we have to stick with the
original version.

>>
>> I just noticed that my unification patch includes some unwanted merge
>> artifact, so it requires another round in any case.
> 
> So I'm discarding the pending pull request entirely. Please re-submit
> when ready.

I just pushed an updated for patch 3 (removing the original "+r"
workaround from the unified version). Please pull now from
git://git.xenomai.org/xenomai-jki.git for-upstream

Jan


[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 257 bytes --]