Re: [musl] Revisiting LFS64 removal

[Rich Felker <dalias@libc.org>]

On Fri, Sep 30, 2022 at 10:35:32AM -0700, Colin Cross wrote:
> On Fri, Sep 30, 2022 at 5:58 AM Rich Felker <dalias@libc.org> wrote:
> >
> > On Fri, Sep 30, 2022 at 04:44:47AM +0200, Markus Wichmann wrote:
> > > On Thu, Sep 29, 2022 at 07:07:08PM -0400, Rich Felker wrote:
> > > > As an alternative, maybe we should consider leaving these but only
> > > > under explict _LARGEFILE64_SOURCE rather than implicitly via
> > > > _GNU_SOURCE for at least one release cycle. This would allow makeshift
> > > > fixing of any builds that break by just adding -D_LARGEFILE64_SOURCE
> > > > until a proper fix can be applied.
> > > >
> > > > Any preference here?
> > > >
> > > > Rich
> > >
> > > Given that nothing lasts as long as a temporary measure, I'd say it is
> >
> > That's not a given for musl, quite the opposite. I would expect it to
> > last at most a release cycle, possibly even to disappear before then
> > if distros backport the changes to their development branches early
> > and find and fix everything.
> >
> > > better to rip the band-aid off in one go rather than two. Besides, any
> > > breakage ought to be able to be dealt with by a simple replacement,
> > > right?
> >
> > It's a simple fix, but the question is how many such simple fixes a
> > distro might need to make in their packages, and that I don't know.
> >
> > If they have a trivial mechanical fix of "add something to CFLAGS"
> > they can do at first, that lets them build a list of affected packages
> > while quickly getting them all building again, then work out the right
> > fixes one at a time according to usual triage rather than being
> > swamped with these taking priority over issues with more depth.
> 
> I experimented with building all the host code in the Android tree
> with these two patches just to measure the damage.  The first patch is
> mostly fine, but causes link failures in rust modules.  I think that's
> due to the upstream rust libc assuming the presence of fstat64, etc.:
> https://cs.android.com/android/platform/superproject/+/master:external/rust/crates/libc/src/unix/linux_like/mod.rs;l=1665;drc=b38fde0ab980c7d79f0a55aec1b7121022a38257

Thanks for running these checks! Do you know where we go about
reporting this to the rust folks? I'd like to get the process started
on getting this fixed asap so hopefully the impact on users is low by
the time it gets to them.

Rich