Split `run-make` into two {`run-make`,`run-make-cargo`} test suites
## Summary
Split `tests/run-make` into two test suites, to make it faster and more convenient for contributors to run run-make tests that do not need in-tree `cargo`.
| New test suites | Explanation |
| ---------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `tests/run-make` | The "fast path" test suite intended for run-make tests that do not need in-tree `cargo`. These tests may not use `cargo`. |
| `tests/run-make-cargo` | The "slow path" test suite that requires checking out `cargo` submodule and building in-tree `cargo`, and thus will have access to in-tree `cargo`. In practice, these constitute a very small portion of the original `run-make` tests. |
This PR carries out [MCP 847: Split run-make test suite into slower-building test suite with suitably-staged cargo and faster-building test suite without cargo](https://github.com/rust-lang/compiler-team/issues/847).
Fixesrust-lang/rust#135573 (for the tests that do not need in-tree `cargo`).
Fixesrust-lang/rust#134109.
## Remarks
- I considered if we want to split by in-tree tools previously. However, as discussed rust-lang/rust#134109, in practice `rustdoc` is not very slow to build, but `cargo` takes a good few minutes. So, the partition boundary was determined to be along in-tree `cargo` availability.
- The `run-make` tests previously that wanted to use `cargo` cannot just use the bootstrap `cargo`, otherwise they would run into situations where bootstrap `cargo` can significantly diverge from in-tree `cargo` (see https://github.com/rust-lang/rust/pull/130642).
---
try-job: aarch64-msvc-1
try-job: test-various
try-job: x86_64-gnu-debug
try-job: aarch64-gnu-debug
try-job: aarch64-apple
try-job: dist-various-1
The run-make test suite contains tests which are the most flexible out of all the rust-lang/rust test suites. run-make tests can basically contain arbitrary code, and are supported by the run_make_support library.
Infrastructure
A run-make test is a test recipe source file rmake.rs accompanied by its parent directory (e.g. tests/run-make/foo/rmake.rs is the foorun-make test).
The setup for the rmake.rs can be summarized as a 3-stage process:
First, we build the run_make_support library in bootstrap as a tool lib.
Then, we compile the rmake.rs "recipe" linking the support library and its dependencies in, and provide a bunch of env vars. We setup a directory structure within build/<target>/test/run-make/
<test-name>/
rmake.exe # recipe binary
rmake_out/ # sources from test sources copied over
and copy non-rmake.rs input support files over to rmake_out/. The support library is made available as an extern prelude.
Finally, we run the recipe binary and set rmake_out/ as the working directory.