CI: add a script for dynamically computing CI job matrix
It would be great if was easier to run specific CI workflows locally, and also to allow us to spawn a specific CI workflow by bors, to enable running arbitrary try builds. See discussion [here](https://rust-lang.zulipchat.com/#narrow/stream/242791-t-infra/topic/CI.20workflows.20refactoring).
This PR is a first step in that direction.
- Moves the definition of CI runners and (for now) PR jobs into a separate `jobs.yml` file.
- Adds a simple Python script that reads the file, decides which jobs should be active for the current CI workflow, and prints them as JSON to their output.
- The PR job then reads this output and generates its job matrix based on it.
By moving the job definitions from `ci.yml` into a separate file, we can handle it programmatically, which should make it easier to both do local execution of CI jobs and also to do arbitrary try builds.
This commit updates how the WASI targets are configured with their
toolchain. Long ago a `config.toml` option of `wasi-root` was added to
enable building with the WASI files produced by wasi-libc. Additionally
for CI testing and release building the Rust toolchain has been using a
hard-coded commit of wasi-libc which is bundled with the release of the
`wasm32-wasip1` target, for example.
Nowadays though the wasi-sdk project, the C/C++ toolchain for WASI, is
the go-to solution for compiling/linking WASI code and contains the
more-or-less official releases of wasi-libc. This commit migrates CI to
using wasi-sdk releases and additionally updates `bootstrap` to
recognize when this is configured. This means that with `$WASI_SDK_PATH`
configured there's no further configuration necessary to get a working
build. Notably this also works better for the new targets of WASI as
well, such as `wasm32-wasip2` and `wasm32-wasip1-threads` where the
wasi-sdk release now has libraries for all targets bundled within it.
Make `split_simd_to_128bit_chunks` take only one operand
It will allow more flexible uses in the future. This makes `split_simd_to_128bit_chunks` simpler, moving some of the complexity to its callers.
Rollup of 4 pull requests
Successful merges:
- #123900 (Stop using `PolyTraitRef` for closure/coroutine predicates already instantiated w placeholders)
- #123924 (Fix various bugs in `ty_kind_suggestion`)
- #123943 (Use the rustc_private libc less in tests)
- #123970 (zkvm: fix references to `os_str` module)
r? `@ghost`
`@rustbot` modify labels: rollup
zkvm: fix references to `os_str` module
The `os_str` module has been moved to `sys`. This change fixes build issues by changing `use` to point to `crate::sys::os_str`.
Use the rustc_private libc less in tests
I started looking into our use of `rustc_private` + `extern crate libc;` in tests because of https://github.com/rust-lang/rust/pull/123938 and it looks like some fraction of the users of libc simply don't need the libc crate anymore.
Fix various bugs in `ty_kind_suggestion`
Consolidates two implementations of `ty_kind_suggestion`
Fixes some misuse of the empty param-env
Fixes a problem where we suggested `(42)` instead of `(42,)` for tuple suggestions
Suggest a value when `return;`, making it consistent with `break;`
Fixes#123906
