Migrate `issue-85401-static-mir`, `missing-crate-dependency` and `unstable-flag-required` `run-make` tests to rmake
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
try-job: armhf-gnu
try-job: test-various
try-job: x86_64-msvc
try-job: aarch64-apple
try-job: dist-x86_64-linux
Migrate 8 very similar FFI `run-make` tests to rmake
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
There are some more of these, but while the code is almost always the same, I want to keep the number reasonable so my doc comments can be inspected for potential inaccuracies. Tell me if 8 is too much, I can cut this down.
For the tracking issue:
- issue-25581
- extern-fn-with-extern-types
- extern-fn-struct-passing-abi
- longjmp-across-rust
- static-extern-type
- extern-fn-explicit-align
- extern-fn-with-packed-struct
- extern-fn-mangle
Rollup of 9 pull requests
Successful merges:
- #125206 (Simplify environment variable examples)
- #126271 (Skip fast path for dec2flt when optimize_for_size)
- #126776 (Clean up more comments near use declarations)
- #127444 (`impl Send + Sync` and override `count` for the `CStr::bytes` iterator)
- #127512 (Terminate `--print link-args` output with newline)
- #127792 (std: Use `read_unaligned` for reads from DWARF)
- #127807 (Use futex.rs for Windows thread parking)
- #127833 (zkvm: add `#[forbid(unsafe_op_in_unsafe_fn)]` in `stdlib`)
- #127836 (std: Forbid unwrapped unsafe ops in xous and uefi modules)
Failed merges:
- #127813 (Prevent double reference in generic futex)
r? `@ghost`
`@rustbot` modify labels: rollup
Migrate `compiler-lookup-paths`, `dump-mono-stats` and `prune-link-args` `run-make` tests to `rmake` or `ui` format
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
try-job: x86_64-msvc
try-job: aarch64-apple
try-job: dist-x86_64-linux
try-job: armhf-gnu
Migrate `std-core-cycle`, `obey-crate-type-flag`, `mixing-libs` and `issue-18943` `run-make` tests to `rmake.rs`
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
try-job: x86_64-apple-1
try-job: x86_64-msvc
try-job: aarch64-gnu
