Fw: [PATCH 1/1] libc: Added implementations and prototypes for

[C Howland]

>
> ------------------------------
> *From:* Newlib <newlib-bounces+craig.howland=caci.com@sourceware.org> on
> behalf of Joel Sherrill <joel@rtems.org>
> *Sent:* Wednesday, July 28, 2021 3:42 PM
> *To:* Newlib <newlib@sourceware.org>; Brian Inglis <
> Brian.Inglis@systematicsw.ab.ca>
> *Subject:* Re: [PATCH 1/1] libc: Added implementations and prototypes for
>
>
> On Wed, Jul 28, 2021 at 1:46 PM Corinna Vinschen <vinschen@redhat.com>
> wrote:
> >
> > On Jul 28 09:25, Brian Inglis wrote:
> > > On 2021-07-28 03:11, Corinna Vinschen wrote:
> > > > Hi Matt,
> > > >
> > > > thanks for this v2.
> > > >
> > > > On Jul 24 10:37, Matt Joyce wrote:
> > > > > Added implementations for sig2str() and str2sig() in libc/signal
> in order
> > > > > to improve POSIX compliance. Added function prototypes to
> sys/signal.h.
> > > > > Added Makefile.am entries to build the new file.
> > > > > ---
> > > > > [...]
> > > > > +#if __GNU_VISIBLE
> > > >
> > > > I think this needs discussion.  The sig2str/str2sig API has not been
> > > > provided yet by GLibC.  Using __GNU_VISIBLE in this context looks
> wrong.
> > > > What we need, in fact, is a __POSIX_VISIBLE guard, but here's the
> > > > problem: As far as I can see, the Issue 8 draft does not yet define a
> > > > version number.
> > > >
> > > > If anybody has better information or a good idea how to guard this
> new
> > > > API in the meantime, I'm all ears.
> > >
> > > Current values are:
> > >
> > > __POSIX_VISIBLE 199009
> > > __POSIX_VISIBLE 199209
> > > __POSIX_VISIBLE 199309
> > > __POSIX_VISIBLE 199506
> > > __POSIX_VISIBLE 200112
> > > __POSIX_VISIBLE 200809
> > > __POSIX_VISIBLE 201402
> > >
> > > and anticipated release date is 2022 from FAQ
> > >
> > >       https://www.opengroup.org/austin/faq.html
> > >
> > >       Q8. Where is the schedule for draft development?
> > >
> > > so could use:
> > >
> > > __POSIX_VISIBLE >= 202202 /* FIXME when POSIX Issue 8 released */
> >
> > Did you mean 202201?  Sounds like a good idea in theory.  But consider a
> > project actually using this value and then the POSIX release defines the
> > value 202207 or so.  The project might stop to compile correctly.  Along
> > these lines, using 202212 for the interim might be the better approach.
> > Then again, what if the release occurs in 2023 only?
> >
> > Still pretty unsure,
>
> Me too.  I told Matthew early on that the header guard for this was going
> to require discussion because I had no idea what was right.
>
> It would be nice to have this available on multiple platforms. Would it be
> acceptable to make the header conditional on Cygwin and RTEMS for now?
> Can we conditionalize the C file for just those two?
>
It really does not matter a whole lot.  The gates are only on the function
prototypes in the header file.  It could just use the date of when the file
is added for the time being, really.
To be more gung-ho, something like
#define POSIX8_RELDATE 202202 // FIXME WHEN REAL RELEASE DATE KNOWN
could be added to sys/features.h, and then this file could use that.
features.h will have to be edited when the new POSIX comes out, so just
place it appropriately to make the need to change it obvious.
Craig

>
> Does newlib have a ticketing/PR system? If so, we could revisit this when
> Issue 8 is released. Alternatively, we can file a ticket in Cygwin and
> RTEMS
> and see which one of us remembers it first after Issue 8 is out. I know if
> we
> tag a ticket with the next release, it should get reviewed as we start
> cleaning
> up as the code gets slushier.
>
> --joel
>
> > Corinna
> >
>
>