The implementation is similiar to macOS solution doesn't
depend on additional OS support

These labels were probably moved around when rustfmt was introduced.

move OS constants to platform crate

to reduce platform specific constants move O_RDONLY etc. and the definition of thread priorities to hermit-abi

Do not lose or reorder user-provided linker arguments

Linker arguments are potentially order-dependent, so the order in which `-C link-arg` and `-C link-args` options are passed to `rustc` should be preserved when they are passed further to the linker.

Also, multiple `-C link-args` options are now appended to each other rather than overwrite each other.

In other words, `-C link-arg=a -C link-args="b c" -C link-args="d e" -C link-arg=f` is now passed as `"a" "b" "c" "d" "e" "f"` and not as `"d" "e" "a" "f"`.

Addresses rust-lang#70505 (comment).

Match options directly in the Fuse implementation

Rather than using `as_ref()`, `as_mut()`, and `?`, we can use `match` directly to save a lot of generated code. This was mentioned as a possibility in rust-lang#70366 (comment), and I found that it had a very large impact on rust-lang#70332 using `Fuse` within `Chain`. Let's evaluate this change on its own first.

…lnay

Stop importing the float modules in documentation

Follow up to rust-lang#69860. I realized I had not searched for and fixed this for the float values. So with this PR they also use the associated constants instead of the module level constants.

For the documentation where it also was using the `consts` submodule I opted to change it to import that directly. This becomes more in line with how other docs that use the `consts` submodule looks. And it also makes it so there are not two `f32` or `f64` things in the current namespace (both the module and the primitive type) and then hopefully confusing documentation readers less.

r? @dtolnay

"cannot resolve" → "cannot satisfy"

CC rust-lang#66523

r? @Centril

Simplify dtor registration for HermitCore by using a list of destructors

The implementation is similar to the macOS version and doesn't depend on additional OS support

…-imports, r=Mark-Simulacrum

Remove marker comments in libstd/lib.rs macro imports

These comments were probably moved around when rustfmt was introduced. They don't correctly denote what they were intended for, so I propose we remove them instead. Thanks!