[PATCH v3 3/5] Use _dl_writev on __libc_message_impl

[Adhemerval Zanella Netto]

On 18/11/25 09:51, Florian Weimer wrote:
> * Adhemerval Zanella Netto:
> 
>> On 18/11/25 04:30, Florian Weimer wrote:
>>> * Adhemerval Zanella:
>>>
>>>> And change _dl_writev to return an negative errno in case of failure.
>>>> This keeps the required semantic on not setting errno in case of
>>>> failure and allow remove the Linux libc_fatal.c implementation.
>>>>
>>>> It also makes is simple to use writev syscall during process startup,
>>>> specially on i386 where it requires to disable the vDSO usage.
>>>
>>> The second part requires moving the implementation into a .c file,
>>> though, and including <startup.h> when that .c file is built?
>>
>> We already have a sysdeps/unix/sysv/linux/i386/dl-writev.h that handles
>> it from 434eca873f14f618d6c2279b54fb809fb56f2c50.
> 
> If <sysdep.h> is included before this (indirectly), it won't work.  I think?

I can double-check, but the elf/tst-assert-startup-static.c (on next patch) 
should stress if this really works. I recall that I change it exactly to
make it work on i686.