Date: Thu, 11 Sep 2025 19:09:19 +0300 From: Konstantin Belousov <kostikbel@gmail.com> To: Alan Somers <asomers@freebsd.org> Cc: Dag-Erling =?utf-8?B?U23DuHJncmF2?= <des@freebsd.org>, Mark Millard <marklmi@yahoo.com>, FreeBSD Current <freebsd-current@freebsd.org>, Konstantin Belousov <kib@freebsd.org> Subject: Re: git: d549de769055 - main - libc: Remove readdir_r(3) [This broke building rust 1.88] Message-ID: <aML0L0TO_z1KMOML@kib.kiev.ua> In-Reply-To: <CAOtMX2gvug65VwPeObKb8Z1mC8H6J6zyHxg3BuzQ_rrp9TVWsQ@mail.gmail.com> References: <1F6A4621-1505-4F78-97C6-85EA556B2165@yahoo.com> <86bjnhi7s2.fsf@ltc.des.dev> <CAOtMX2gJJ-wGtK3%2BQwyz_eODYWK6pwaMA6gbnN74Pvqc1QW6Mw@mail.gmail.com> <86zfb1ghj7.fsf@ltc.des.dev> <CAOtMX2gvug65VwPeObKb8Z1mC8H6J6zyHxg3BuzQ_rrp9TVWsQ@mail.gmail.com>
index | next in thread | previous in thread | raw e-mail
On Thu, Sep 11, 2025 at 09:45:19AM -0600, Alan Somers wrote: > On Thu, Sep 11, 2025 at 9:01 AM Dag-Erling Smørgrav <des@freebsd.org> wrote: > > > Alan Somers <asomers@freebsd.org> writes: > > > Dag-Erling Smørgrav <des@freebsd.org> writes: > > > > Tell that to the Rust developers. They have been repeatedly warned > > > > against using readdir_r(3) for years, as far back as 2016. > > > Have they? Looking at rust's github page, I see discussions about > > > using readdir_r on Fuchsia and Linux, but nothing about BSD. > > > > If you look at these tickets, there are people pointing out that > > readdir_r() doesn't work correctly even on platforms where it isn't > > formally deprecated. The Rust developers chose to fix the Linux case > > because it produced a link-time warning and ignored the rest. That's on > > them. > > > > They also seem to be providing their own prototype for readdir_r(), > > which suppresses the deprecation warning they should be getting on > > FreeBSD 15, and turns the issue from a failure to compile into a failure > > to link. That's also on them. > > > > Where do you see that? I suppose you must be talking about this line in > libc. That's not due to anything special about readdir_r; it's just the > way that Rust links to _every_ libc function. There is a CI step that > ensures these FFI definitions are accurate. > https://github.com/rust-lang/libc/blob/61b722e2517775cea98428702710ee9ef00f02a0/src/unix/mod.rs#L1769C22-L1769C23 > > > > > > > possibly with the aid of installing misc/compat14x > > > > That won't make any difference since readdir_r() is still in our libc. > > > > DES > > -- > > Dag-Erling Smørgrav - des@FreeBSD.org > > > > There's another problem that we haven't discussed, which is the ability to > run older Rust toolchains. Even if we fix Rust 1.89.0 to no longer use > readdir_r, older versions will continue to do so. And Rust developers > frequently must test with older toolchains. For example, any change to > Rust's libc requires testing with version 1.63.0, released in August 2022. > We can't remove readdir_r without breaking all of those workflows. We > could probably remove the prototype, but not the function itself. Binaries that were succesfully linked, continue to work. If you take any binary that already used readdir_r@FBSD_1.5, it is unchanged. Symbol is there, but the default version of it not.home | help
Want to link to this message? Use this
URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?aML0L0TO_z1KMOML>