[PATCH v2] Implement C23 memalignment

[Joseph Myers]

On Mon, 13 Oct 2025, Florian Weimer wrote:

> * Joseph Myers:
> 
> > On Fri, 10 Oct 2025, Florian Weimer wrote:
> >
> >> * Joseph Myers:
> >> 
> >> > Add the C23 memalignment function (query the alignment of a pointer)
> >> > to glibc.
> >> >
> >> > Given how simple this operation is, it would make sense for compilers
> >> > to inline calls to this function, but I'm treating that as a compiler
> >> > matter (compilers should add it as a built-in function) rather than
> >> > adding an inline version to glibc headers (although such an inline
> >> > version would be reasonable as well).  I've filed
> >> > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122117 for this feature
> >> > in GCC.
> >> 
> >> Should this function be added to libc_nonshared.a until the standard is
> >> released, in case its definition changes in subsequent drafts?
> >
> > This function is from C23, not C2y.
> 
> Oh okay, so that part of my response is clearly wrong.
> 
> What about my suggestion regarding the performance advice in the manual?

I put your wording for that into the v3 patch submission.

-- 
Joseph S. Myers
josmyers@redhat.com