rust-analyzer failed to load workspace

[Redoubts]

I installed rust with brew on MacOS, and I'm noticing this error on a hello world project with VS Code:

rust-analyzer failed to load workspace: 
    Failed to find sysroot for Cargo.toml file ./rust_new/Cargo.toml. 
    Is rust-src installed?: rustup component add rust-src failed

I didn't install with rustup, and I figured I wouldn't need to. This suggests I must, but why? Does this suggest I need the complier source to use your package in my editor?

[lnicola]

rust-src is the standard library, not compiler source code. rust-analyzer needs it to know what the standard library types are.

[Redoubts]

Isn't that rust-std? Rust's homepage describes rust-src as the Rust source code.

https://github.com/rust-lang/rustup#can-rustup-download-the-rust-source-code

[bjorn3]

rust-src is the source code of the standard library. rust-std is the compiled version of the standard library.

[zdcthomas]

Hey,
I just upgraded to the newest rust-analyzer version, and I've just started having the same issue.

• I'm using nvim with coc-rust-analyzer
• I've run rustup update
• Ive run rustup comonent add rust-src
  the only thing left that I can think of doing is setting RUST_SRC_PATH but I'm not sure what to set that to/why I only now have to set it.

[bjorn3]

What is the output of ls $(rustc --print sysroot)/lib/rustlib/src/rust/src? For me it is:

build_helper  libcore         libpanic_unwind  libprofiler_builtins  librustc_asan  librustc_msan  libstd     libterm  libunwind  tools
liballoc      libpanic_abort  libproc_macro    librustc              librustc_lsan  librustc_tsan  libsyntax  libtest  stdarch

[zdcthomas]

it seems like I only have the path up to lib/rustlib I don't have src/rust/src, should I reinstall stuff? What I have in rustlib is

components                              manifest-rustc
etc                                     rust-installer-version
manifest-rust-docs                      x86_64-apple-darwin
manifest-rust-std-x86_64-apple-darwin

[zdcthomas]

Quick update, I uninstalled all of the rust toolchain, and then reinstalled and the issue has gone away

[matklad]

Closing the issue, as it seems to be the problem with local toolchain installation. it would be awesome if we could diagnose and warn about this on our side, but I doubt we can provide info more useful then the existing error message.

[woelper]

I have the same issue with nightly-x86_64-unknown-linux-gnu (1.48.0-nightly) on ubintu linux and vs code. I have completely uninstalled rust and reinstalled, but I get

rust-analyzer failed to load workspace: Failed to find sysroot for Cargo.toml file /mnt/md2/woelper/dircpy/Cargo.toml.
Is rust-src installed?:
can't load standard library from sysroot /home/woelper/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/src (discovered via `rustc --print sysroot`)
try running `rustup component add rust-src` or set `RUST_SRC_PATH`

running rustup component add rust-src yields info: component 'rust-src' is up to date.

it looks like I am missing the src folder: ls /home/woelper/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu/lib/rustlib/src/rust shows just Cargo.lock library.

$(rustc --print sysroot) points to /home/woelper/.rustup/toolchains/nightly-x86_64-unknown-linux-gnu, which does exist.

I should add that this is a VS code remote session, maybe this complicates things?

[bjorn3]

Try rustup component add rust-src --toolchain nightly.

[woelper]

rustup component add rust-src --toolchain nightly

Thanks for your reply, this produces the following result:

rustup component add rust-src --toolchain nightly
info: component 'rust-src' is up to date

[woelper]

I am able to reproduce this with Mac OS 10.15.6 and 1.48.0-nightly as well:

rust-analyzer failed to load workspace:
Failed to find sysroot for Cargo.toml file /Users/woelper/catapult-imgui/Cargo.toml. Is rust-src installed?
Caused by: can't load standard library from sysroot /Users/woelper/.rustup/toolchains/nightly-x86_64-apple-darwin/lib/rustlib/src/rust/src (discovered via `rustc --print sysroot`) try running `rustup component add rust-src` or set `RUST_SRC_PATH`

I also ran rustup component add rust-src --toolchain nightly, which caused info: component 'rust-src' is up to date

[jondot]

rust-src changed the path layout, which is the source of the problem.

September:

August:

[jondot]

Lastly, this should be fixed if you take recent version from master:
6b8bc13#diff-30888fefce138d15c65ceb40b37b7ad2R146