src/unix/hermit/ is dead code as hermit is no longer cfg(unix)

[egrimley-arm]

As verified with

rustc -Z unstable-options --target=aarch64-unknown-hermit --print target-spec-json | grep unix

hermit had "target-family": "unix" removed between versions 1.39.0 and 1.40.0 of rustc, or between nightly-2019-10-26 and nightly-2019-10-27.

This may well not be a bug in libc but I would like to know how to access the types defined in src/unix/hermit/ when using a recent version of rustc.

(@stlankes made relevant changes to libc and rustc and might be able to help.)

[stlankes]

@mkroening Please correct me, if I am wrong.

During the years it changed and hermit doesn't belong to the family unix. Consequently it is dead code. Should I remove it?

[egrimley-arm]

Are some of the types defined in src/unix/hermit/ needed for vsock (hermit-os/kernel#826)?

[mkroening]

Stefan changed this in rust-lang/rust@c1e440a#R22.

This was when we migrated away from newlib for Rust userspace and directly called into the kernel instead. So I'd say, anything #[cfg(all(target_os = "hermit", unix))] is safe to remove.

[stlankes]

I don't think that we these types to realize vsock.

[mkroening]

@rustbot claim