I'm aware of that, I guess my point was that Rust probably doesn't use a lot of glibc (like most C programs would) so the utility of LD_PRELOAD is quite minimal.
I don't know enough about .rlib to know whether you could overwrite Rust library functions, but that's a different topic.
Right, but does that mean it's only used as a way of getting syscall numbers (without embedding it like Go does) or is it the case that you could actually LD_PRELOAD random things like nftw(3) and it would actually affect Rust programs? I'll be honest, I haven't tried it, but it was my impression that Rust only used glibc for syscall wrappers?
I don't know enough about .rlib to know whether you could overwrite Rust library functions, but that's a different topic.