bootstrap: fully rely on RUSTC_WRAPPER

[RalfJung]

With rust-lang/cargo#13659, cargo now respects RUSTC_WRAPPER for all rustc invocations. That means we can finally remove the hack where we set our wrapper as both RUSTC and RUSTC_WRAPPER.

There could still be build scripts that fail to respect RUSTC_WRAPPER, but then we should fix those before they become a rustc dependency.

Fixes #128383

[rustbot]

r? @Kobzol

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[RalfJung]

Turns out even our own libc crate doesn't properly wrap its rustc invocations.^^ I guess I did not hit this locally as the build script was already cached.
Blocked on rust-lang/libc#3772.

[Kobzol]

@rustbot blocked

[RalfJung]

Locally a check-build passes now, let's see what CI says...

[RalfJung]

I guess I still had cached build script results somewhere.

The next offender is: field-offset. It uses rustc_version, so hopefully we just need to pull in the just-released version 0.4.1.

[rustbot]

These commits modify the Cargo.lock file. Unintentional changes to Cargo.lock can be introduced when switching branches and rebasing PRs.

If this was unintentional then you should revert the changes before this PR is merged.
Otherwise, you can ignore this comment.

[rustbot]

Some changes occurred in compiler/rustc_codegen_gcc

cc @antoyo, @GuillaumeGomez

Some changes occurred in compiler/rustc_codegen_cranelift

cc @bjorn3

[rustbot]

rust-analyzer is developed in its own repository. If possible, consider making this change to rust-lang/rust-analyzer instead.

cc @rust-lang/rust-analyzer

[rust-log-analyzer]

The job mingw-check failed! Check out the build log: (web) (plain)

Click to see the possible cause of the failure (guessed by this bot)

#16 2.731 Building wheels for collected packages: reuse
#16 2.732   Building wheel for reuse (pyproject.toml): started
#16 2.979   Building wheel for reuse (pyproject.toml): finished with status 'done'
#16 2.980   Created wheel for reuse: filename=reuse-4.0.3-cp310-cp310-manylinux_2_35_x86_64.whl size=132715 sha256=dfa09868353292d98f811d3efdb0d54d07389e808efc71d68e3b93c514bf8bec
#16 2.980   Stored in directory: /tmp/pip-ephem-wheel-cache-222mtqlt/wheels/3d/8d/0a/e0fc6aba4494b28a967ab5eaf951c121d9c677958714e34532
#16 2.983 Installing collected packages: boolean-py, binaryornot, tomlkit, reuse, python-debian, markupsafe, license-expression, jinja2, chardet, attrs
#16 3.375 Successfully installed attrs-23.2.0 binaryornot-0.4.4 boolean-py-4.0 chardet-5.2.0 jinja2-3.1.4 license-expression-30.3.0 markupsafe-2.1.5 python-debian-0.1.49 reuse-4.0.3 tomlkit-0.13.0
#16 3.375 WARNING: Running pip as the 'root' user can result in broken permissions and conflicting behaviour with the system package manager. It is recommended to use a virtual environment instead: https://pip.pypa.io/warnings/venv
#16 DONE 3.5s
---

Caused by:
  process didn't exit successfully: `/checkout/obj/build/x86_64-unknown-linux-gnu/stage0-tools/release/build/protobuf-36e7809420578a1e/build-script-build` (exit status: 101)
  --- stderr
  thread 'main' panicked at /cargo/registry/src/index.crates.io-6f17d22bba15001f/protobuf-3.2.0/build.rs:28:10:
  spawn rustc: Os { code: 2, kind: NotFound, message: "No such file or directory" }
warning: build failed, waiting for other jobs to finish...
Build completed unsuccessfully in 0:04:01
  local time: Wed Aug 28 12:02:42 UTC 2024
  network time: Wed, 28 Aug 2024 12:02:42 GMT

[RalfJung]

Blocked on stepancheg/rust-protobuf#735.