fs::metadata() crashes on FreeBSD 12 due to layout change in stat.h

[lukaslueg]

The layout of struct stat used to be this in FreeBSD 11, in FreeBSD 12 it's now this. This causes the FreeBSD-specific implementation of std::fs::metadata() to crash for 1.18 and nightly as of 17/06/15, as it's stack frame get's boiled up.

Can be reproduced via

use std::fs;
fn main() {
    println!("{:?}", fs::metadata("Cargo.toml"));
}

Downstream this appeared in alacritty/alacritty#618

[semarie]

I would like to point a pre-RFC discussion about introducing a way in Rust to permit libc to represent differents layouts per OS version. I think there is need to move forward.

[alexcrichton]

We discussed this at libs triage today and the conclusion was that this is indeed bad! We would be fine in the very near future adding dynamic detection to do the right thing at runtime. In the long term we decided to see how @semarie's rfc plays out.

[johalun]

Is there a quick fix for this? This stops me from building a few (probably many) crates..

[johalun]

Here's a temporary fix for those who can't wait
https://github.com/johalun/rust-ino64
Just re-apply each time you update nightly with rustup.