`cargo fmt` and other tools don't work for a linked toolchain.

[vext01]

This is derived from this issue, in which we concluded that the bug should be filed against rustc, as it's an x.py problem.

In rustc:

$ ./x.py build --stage 1 src/tools/rustfmt/
...
$ find 'build' -name rustfmt
build/x86_64-unknown-linux-gnu/stage1-tools/x86_64-unknown-linux-gnu/release/rustfmt
build/x86_64-unknown-linux-gnu/stage1-tools-bin/rustfmt
build/x86_64-unknown-linux-gnu/stage0/share/doc/rustfmt
build/x86_64-unknown-linux-gnu/stage0/bin/rustfmt
build/tmp-rustbuild-tests/main/tmp/tarball/rustfmt
build/tmp-rustbuild-tests/main/tmp/tarball/rustfmt/B/image/share/doc/rustfmt

Then in a project using this toolchain via a rustup link:

$ cargo fmt
error: 'cargo-fmt' is not installed for the toolchain 'yk-stage1'
note: this is a custom toolchain, which cannot use `rustup component add`
help: if you built this toolchain from source, and used `rustup toolchain link`, then you may be able to build the component with `x.py`                                                                           

But note that cp build/x86_64-unknown-linux-gnu/stage1-tools-bin/rustfmt build/x86_64-unknown-linux-gnu/stage1/bin/rustfmt does not make this work either, so there is probably more to it?

Thanks

[vext01]

[removed comment, wrong issue, sorry]

[camelid]

(I think you posted that comment in the wrong place.)

[vext01]

Oops, yes.

[vext01]

Can anyone comment on what the correct fix for this might be?

I notice that if I copy cargo-clippy and clippy-driver from stage1-tools-bin/ into stage1/bin then I'm able to run cargo clippy via the linked toolchain.

I initially considered changing rustup to add stage1-tools-bin to the PATH, but that seems incorrect as we would be adding something outside of the toolchain root to PATH.

So should x.py copy or move the binaries from stage1-tools-bin into stage1/bin?

I'm willing to (attempt to) do the work if we can agree on what the correct fix is.

[camelid]

Can anyone comment on what the correct fix for this might be?

I'm not really knowledgeable about x.py. You might want to ask in #t-compiler on Zulip.

[jyn514]

So should x.py copy or move the binaries from stage1-tools-bin into stage1/bin?

Yes, it should copy the binaries from stage1-tools-bin to stage1/bin.

[jyn514]

Mentoring instructions: Add a new argument to the bootstrap_tool macro that says whether the tool should be added to the sysroot, then copy it into the sysroot just after

rust/src/bootstrap/tool.rs

Lines 223 to 224 in 4a7e2fb

	let bin = builder.tools_dir(compiler).join(exe(tool, target));
	builder.copy(&cargo_out, &bin);

[WaffleLapkin]

I believe this will be fixed by #102010, once we figure out some problems with clippy/fmt builds.