add missing error numbers for HermitOS

[stlankes]

HermitOS is a unikernel and its interface to the kernel is provided by https://crates.io/crates/hermit-abi. In the meantime parts of the interface is stabilized and we want to integrated it into libc. Unstable version will be still provided by hermit-abi.

Error numbers are missing in the main branch.

[rustbot]

r? @JohnTitor

rustbot has assigned @JohnTitor.
They will have a look at your PR within the next two weeks and either review your PR or reassign to another reviewer.

Use r? to explicitly pick a reviewer

[stlankes]

@rustbot label +stable-nominated

[stlankes]

See also #3766

[tgross35]

The numbers all looks correct to me. However, the linked source at https://github.com/hermit-os/hermit-rs/blob/5a4d7efe1ab5727cf4d5299943aa8deaa098a603/hermit-abi/src/errno.rs looks like it always uses i32, not c_int that is used in this PR. Probably better to just use i32 here as well?

Also, could you start a file libc-test/semver/hermit.txt and add these? This won't be checked in CI but just run the tests locally and make sure they pass.

@rustbot author

[stlankes]

c_int is defined as i32 (https://github.com/rust-lang/libc/blob/main/src/hermit.rs#L15). Hm, it irritates a little. We thought that this easier to understand because all other OS are using c_int. We can change it, I am open for it.

Also, could you start a file libc-test/semver/hermit.txt and add these? This won't be checked in CI but just run the tests locally and make sure they pass.

I will do it

[tgross35]

c_int is defined as i32 (https://github.com/rust-lang/libc/blob/main/src/hermit.rs#L15). Hm, it irritates a little. We thought that this easier to understand because all other OS are using c_int. We can change it, I am open for it.

Regardless of how the type aliases are defined, prefer being consistent with the relevant headers / source files over being consistent with other platforms. Doesn't really matter here since c_int is almost always i32, but it makes it easier to verify that we don't quietly introduce bugs.

Looks like this is already done elsewhere, e.g. SO_REUSEADDR is a c_int on most platforms but an i32 on Hermit.

[stlankes]

Ok, I thought about it. I will change it to i32.

[tgross35]

Thanks! Can you add libc-test/semver/hermit.txt?

[stlankes]

I just added libc-test/semver/hermit.txt.

[tgross35]

I only meant to include the API added here, the rest could come later. But even better that you did it all now I suppose :)

Thanks!