Rust-analyzer failing to work.

[gleocadie]

I have a Dev Container config where I use rust:1 devcontainer feature .

I open my repo using VS Code inside WSL, I get the Open in container... and click on it. The container is successfully created and at some point rust-analyzer reports an issue

ERROR failed fetching data layout for ManifestPath { file: AbsPathBuf("/workspaces/libdatadog/Cargo.toml") } workspace e=unable to fetch target-data-layout via `cd "/workspaces/libdatadog" && RUSTC_BOOTSTRAP="1" RUSTUP_TOOLCHAIN="/usr/local" "/usr/local/cargo/bin/rustc" "-Z" "unstable-options" "--print" "target-spec-json"`
2025-08-01T10:38:30.932545354Z ERROR failed fetching data layout for ManifestPath { file: AbsPathBuf("/workspaces/libdatadog/Cargo.toml") } workspace e=unable to fetch target-data-layout via `cd "/workspaces/libdatadog" && RUSTC_BOOTSTRAP="1" RUSTUP_TOOLCHAIN="/usr/local" "/usr/local/cargo/bin/rustc" "-Z" "unstable-options" "--print" "target-spec-json"`
2025-08-01T10:38:31.529452361Z ERROR Flycheck failed to run the following command: CommandHandle { program: "/usr/local/cargo/bin/cargo", arguments: ["check", "--workspace", "--message-format=json-diagnostic-rendered-ansi", "--manifest-path", "/workspaces/libdatadog/Cargo.toml", "--keep-going", "--all-targets"], current_dir: Some("/workspaces/libdatadog") }, error=Cargo watcher failed, the command produced no valid metadata (exit code: ExitStatus(unix_wait_status(25856))):
warning: /workspaces/libdatadog/datadog-crashtracker-ffi/Cargo.toml: unused manifest key: target.cfg(windows).features
error: process didn't exit successfully: `rustc -vV` (exit status: 1)
--- stderr
error: 'rustc' is not installed for the custom toolchain '/usr/local'.
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`

Any idea how to make this work please ?

[Kaniska244]

Hello @gleocadie ,

Thank you for reporting this issue. Would you kindly check and let me know the toolchain/ default toolchain being used in this case?

[gleocadie]

👋 @Kaniska244
I ran rustc -vV and got this

vscode ➜ /workspaces/libdatadog $ rustc -vV
rustc 1.88.0 (6b00bc388 2025-06-23)
binary: rustc
commit-hash: 6b00bc3880198600130e1cf62b8f8a93494488cc
commit-date: 2025-06-23
host: x86_64-unknown-linux-gnu
release: 1.88.0
LLVM version: 20.1.5

vscode ➜ /workspaces/libdatadog $ cargo --version
cargo 1.88.0 (873a06493 2025-05-10)

Do not hesitate to ask me commands to run.
Thanks for your help.

[gleocadie]

👋 @Kaniska244 any news on that ?

[Kaniska244]

Hello @gleocadie ,

Apologies for the delay from my end, I will check and update you this week.