Add support for downloading GCC from CI
This PR adds a new bootstrap config section called `gcc` and implements a single config `download-ci-gcc`. Its behavior is similar to `download-ci-llvm`. Since https://github.com/rust-lang/rust/pull/137667, we distribute a CI component that contains the prebuilt `libgccjit.so` library on x64 Linux. With `download-ci-gcc`, this component is downloaded from CI to avoid building GCC locally.
This is an MVP of this functionality, designed for local usage. This PR does not enable this functionality on the LLVM 18 PR CI job which builds `cg_gcc`, and does not implement more complex detection logic. It simply uses `false` (build locally) or `true` (download from CI if you're on the right target, if CI download fails, then bootstrap fails).
The original LLVM CI download functionality has a lot of features and complexity, which we don't need for GCC (yet). I don't like how the LLVM CI stuff is threaded through multiple parts of bootstrap, so with GCC I would like to take a more centralized approach, where the `build::Gcc` step handles download from CI internally. This means that:
- For the rest of bootstrap, it should be transparent whether GCC was built locally or downloaded from CI.
- GCC is not downloaded eagerly unless you actually requested GCC (either you requested `x build gcc` or you asked to build/test the GCC backend).
This approach will require some modifications once we extend this feature, but so far I like this approach much more than putting this stuff into `Config[::parse]`, which already does a ton of stuff that it arguably shouldn't (but it's super difficult to extract its logic out).
This PR is an alternative to https://github.com/rust-lang/rust/pull/130749, which did a more 1:1 copy of the `download-ci-llvm` logic.
r? ``@onur-ozkan``
Mention me (WaffleLapkin) when changes to `rustc_codegen_ssa` occur
My employer is writing a rustc backend and it's my job to resolve conflicts with upstream so I'd like to know when `rustc_codegen_ssa` is being changed =)
Retire the legacy `Makefile`-based `run-make` test infra
The final piece of [porting run-make tests to use Rust #121876](https://github.com/rust-lang/rust/issues/121876).
Closes#121876.
Closes#40713.
Closes#81791 (no longer using `wc`).
Closes#56475 (no longer a problem in current form of that test; we don't ignore the test on `aarch64-unknown-linux-gnu`).
### Summary
This PR removes the legacy `Makefile`-based `run-make` test infra which has served us well over the years. The legacy infra is no longer needed since we ported all of `Makefile`-based `run-make` tests to the new `rmake.rs` infra.
Additionally, this PR:
- Removes `tests/run-make/tools.mk` since no more `Makefile`-based tests remain.
- Updates `tests/run-make/README.md` and rustc-dev-guide docs to remove mention about `Makefile`-based `run-make` tests
- Update test suite requirements in rustc-dev-guide on Windows to no longer need MSYS2 (they should also now run successfully on native Windows MSVC).
- Update `triagebot.toml` to stop backlinking to #121876.
**Thanks to everyone who helped in this effort to modernize the `run-make` test infra and test suite!**
r? bootstrap
This happened because `test/rustdoc-js` is a prefix of `test/rustdoc-json`, and triagebot works on prefixes.
Maybe this should be fixed in triagebot, but this works now.
Adjust triagebot.toml entries for `rustc_mir_build/src/builder/`
I only just noticed that these paths were silently broken by the renaming of `build` to `builder` in #134365.
This is *possibly* OK to just self-approve, but I would prefer to get a second set of eyes on it just in case.
Rollup of 5 pull requests
Successful merges:
- #134679 (Windows: remove readonly files)
- #136213 (Allow Rust to use a number of libc filesystem calls)
- #136530 (Implement `x perf` directly in bootstrap)
- #136601 (Detect (non-raw) borrows of null ZST pointers in CheckNull)
- #136659 (Pick the max DWARF version when LTO'ing modules with different versions )
r? `@ghost`
`@rustbot` modify labels: rollup
dev guide ping group and set adhoc reviewers to compiler
r? ``@jieyouxu`` ``@Kobzol``
I added you both to the `cc` list since you're both also on the list of owners for `src/doc/rustc-dev-guide`
