Misleading deprecated component message for non-host toolchain

[sgentle]

Verification

• I searched for recent similar issues at https://github.com/rust-lang/rustup/issues?q=is%3Aissue and found no duplicates.
• I am on the latest version of Rustup according to https://github.com/rust-lang/rustup/tags and am still able to reproduce my issue.

Problem

I got the following error while running rustup update:

error: component 'rls-preview' for target 'x86_64-apple-darwin' is unavailable for download for channel 'stable'
One or many components listed above might have been permanently removed from newer versions
of the official Rust distribution due to deprecation.

You can find the list of removed components at
<https://rust-lang.github.io/rustup/devel/concepts/components.html#previous-components>.

If you are updating an existing toolchain, after determining the deprecated component(s)
and/or target(s) in question, please remove them with:

    rustup component remove --toolchain stable <COMPONENT>...
    rustup target remove --toolchain stable <TARGET>...

After that, you should be able to continue with the update as usual.

     stable-aarch64-apple-darwin unchanged - rustc 1.94.0 (4a4ef493e 2026-03-02)
  stable-x86_64-apple-darwin update failed - rustc 1.84.0 (9fc6b4312 2025-01-07)

I found the previous issue #4339, but in my case rustup component remove --toolchain stable rls failed with this message:

error: toolchain 'stable-aarch64-apple-darwin' does not contain component 'rls' for target 'aarch64-apple-darwin'

However, rustup component remove --toolchain stable-x86_64-apple-darwin rls-preview worked.

So really this is just a documentation issue – it should probably suggest the full toolchain including host.

Steps

1. rustup update

Possible Solution(s)

No response

Notes

No response

Rustup version

1.29.0

Installed toolchains

Default host: aarch64-apple-darwin
rustup home:  /Users/samg/.rustup

installed toolchains
--------------------
stable-aarch64-apple-darwin (active, default)
stable-x86_64-apple-darwin
nightly-aarch64-apple-darwin
nightly-x86_64-apple-darwin
nightly-2021-01-07-x86_64-apple-darwin
nightly-2022-07-13-x86_64-apple-darwin
1.81.0-aarch64-apple-darwin
esp

active toolchain
----------------
name: stable-aarch64-apple-darwin
active because: it's the default toolchain
installed targets:
  aarch64-apple-darwin
  aarch64-unknown-linux-gnu

OS version

Mac OS X 14