Use the same rust-toolchain for all Rust sub-projects

[breezewish]

What problem does this PR solve?

Issue Number: close #7198

Problem Summary:

What is changed and how it works?

Use a symbolic link, one for all!

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)

1. Cargo respects the rust-toolchain symbolic link override in the TiFlash root:

 ~/Work/tiflash-workspace2/libs/libsymbolization
❯ rustup toolchain list
stable-aarch64-apple-darwin
nightly-2021-04-15-aarch64-apple-darwin
nightly-2021-07-28-aarch64-apple-darwin
nightly-2022-02-14-aarch64-apple-darwin
nightly-2022-05-01-aarch64-apple-darwin
nightly-2022-06-20-aarch64-apple-darwin
nightly-2022-07-31-aarch64-apple-darwin
nightly-2022-11-15-aarch64-apple-darwin (override)
nightly-aarch64-apple-darwin (default)

 ~/Work/tiflash-workspace2/libs/libsymbolization
❯ cat ../../contrib/tiflash-proxy/rust-toolchain
───────┬──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
       │ File: ../../contrib/tiflash-proxy/rust-toolchain
───────┼──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
   1   │ nightly-2022-11-15
───────┴──────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────

2. cmake triggers a recompile when tiflash-proxy/rust-toolchain is changed:

 ~/Work/tiflash-workspace2/cmake-build-debug
❯ echo "nightly-2022-07-31" > ../contrib/tiflash-proxy/rust-toolchain

 ~/Work/tiflash-workspace2/cmake-build-debug
❯ ninja tiflash
[0/2] Re-checking globbed directories...
[0/3] Building symbolization using release profile
   Compiling cc v1.0.73
   Compiling memchr v2.4.1
   Compiling autocfg v1.1.0
   Compiling libc v0.2.120
   Compiling adler v1.0.2
   Compiling gimli v0.26.1
   Compiling cfg-if v1.0.0
   Compiling lazy_static v1.4.0
   Compiling rustc-demangle v0.1.21
   Compiling miniz_oxide v0.4.4
   Compiling backtrace v0.3.64
   Compiling findshlibs v0.10.2
   Compiling addr2line v0.17.0
   Compiling object v0.27.1
   Compiling symbolization v0.0.1 (/Users/breezewish/Work/tiflash-workspace2/libs/libsymbolization)
    Finished release [optimized + debuginfo] target(s) in 3.76s

• No code

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• CalvinNeo
• Lloyd-Pottiger

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[CalvinNeo]

lgtm

[breezewish]

/merge

[ti-chi-bot]

@breezewish: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

You only need to trigger /merge once, and if the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

If you have any questions about the PR merge process, please refer to pr process.

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[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 67f9456

[ti-chi-bot]

@breezewish: Your PR was out of date, I have automatically updated it for you.

At the same time I will also trigger all tests for you:

/run-all-tests

trigger some heavy tests which will not run always when PR updated.

If the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.