`x build src/tools/miri` doesn't install miri as part of the built toolchain

[Kixiron]

Running x build src/tools/miri doesn't include miri as part of the built rust toolchain, meaning that cargo +custom-toolchain miri doesn't work

cc @jyn514

[Kixiron]

@rustbot label +A-rustbuild

[WaffleLapkin]

It seems like the same thing happens to rustfmt: x b rustfmt doesn't include rustfmt as part of the built rust toolchain, meaning that rustfmt +custom-toolchain doesn't work.

[daxpedda]

The same thing applies to cargo and clippy.

[jyn514]

We need to call add_to_sysroot in all of these steps. I think that currently adds all libraries as well which isn't correct - someone should look into how this is done for rustdoc and do the same for the other tools. Take a look around src/bootstrap/compile.rs.

I agree it's a bug that we don't copy these today.

[WaffleLapkin]

@rustbot claim

[Emilgardis]

this seems related to #81431

[onur-ozkan]

@rustbot claim