Re: [musl] C23 implications for C libraries

[Gabriel Ravier <gabravier@gmail.com>]

[-- Attachment #1: Type: text/plain, Size: 2485 bytes --]

On 5/4/23 18:03, enh wrote:
>
>
> On Wed, May 3, 2023 at 11:19 PM Jₑₙₛ Gustedt <jens.gustedt@inria.fr> 
> wrote:
>
>     Hi,
>
>     on Wed, 3 May 2023 15:58:26 -0700 you (enh <enh@google.com>) wrote:
>
>     > (i share others' skepticism that timespec_get() is very useful,
>
>     I don't think that these interfaces by themselves are the most
>     interesting. The original motivation to create these interfaces stem
>     from the creation the integration of threads in to the C standard. And
>     there the monotonic and thread-specific clocks make all their sense.
>
>     But also having process cpu usage in a well-defined interface (`clock`
>     usage is not portable for that) is a win.
>
>
> sure, but the more esoteric the clocks, the less likely _that_ part is 
> to be portable anyway.
>
>     > and especially that non-ISO bases will ever be useful to anyway, but
>     > i like the idea of allowing future additions to "just work" with an
>     > old libc enough that i've implemented bionic's
>     > timespec_get()/timespec_getres() in this style.)
>
>     Great!
>
>     Do you have a link to that? 
>
>
> https://android-review.googlesource.com/c/platform/bionic/+/2576754
>
>     The particular choices of values become
>     part of the ABI, sort-of. So it would be better to be consistent
>     between implementations.
>
>
> are there any two linux libcs that are abi compatible? i didn't think so.

musl aims to have binary compatibility with glibc, so it very much 
matters in this case

>     Would this motivate musl to accept patches for the optional bases that
>     come with C23? Or maybe the whole set?
>
>
> i think bionic and musl are philosophically quite different there --- 
> musl seems to try to stick to the exact letter of ISO/POSIX, whereas 
> with bionic i accept that for everything you can possibly imagine, 
> _someone_ will be trying to do it, and -- unless you're actually going 
> to prohibit it via selinux/seccomp for security or privacy reasons -- 
> i may as well make it as minimally painful as possible.
>
>     Thanks
>     Jₑₙₛ
>
>     -- 
>     :: ICube :::::::::::::::::::::::::::::: deputy director ::
>     :: Université de Strasbourg :::::::::::::::::::::: ICPS ::
>     :: INRIA Nancy Grand Est :::::::::::::::::::::::: Camus ::
>     :: :::::::::::::::::::::::::::::::::::: ☎ +33 368854536
>     <tel:+33%203%2068%2085%2045%2036> ::
>     :: https://icube-icps.unistra.fr/index.php/Jens_Gustedt ::
>

[-- Attachment #2: Type: text/html, Size: 5865 bytes --]