fly check panic

[qjerome]

rust-analyzer version: 0.3.2264

rustc version: rustc 1.81.0 (eeb90cda1 2024-09-04)

editor or extension: VSCode

I am getting this error:

2025-01-16T14:02:42.513421189+01:00 ERROR flycheck task panicked: Any { .. }
thread 'Worker' panicked at crates/rust-analyzer/src/handlers/notification.rs:333:25:
index out of bounds: the len is 1 but the index is 1
stack backtrace:
   0: rust_begin_unwind
   1: core::panicking::panic_fmt
   2: core::panicking::panic_bounds_check
   3: core::ops::function::FnOnce::call_once{{vtable.shim}}
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
2025-01-16T14:02:45.05267552+01:00 ERROR flycheck task panicked: Any { .. }

I checked the code at https://github.com/rust-lang/rust-analyzer/blob/1f717b0acdccf6969655a8a1ddf6b718dfba6ca6/crates/rust-analyzer/src/handlers/notification.rs#L333C1-L333C82 and it seems the accessed index is not checked against OOB access. As I am not very familiar with the r-a code base I am tempted to fix this just checking that idx is in bounds using get methods instead of [] access but maybe it is the symptom of an issue that needs to be corrected elsewhere in the code.

Cheers,

[Veykril]

There seems to be something else going on, the index there should always be in bounds, though we might be racing when the workspaces switch.

[qjerome]

Let me know if I can help diagnosing the issue

[ChayimFriedman2]

Do you have a reproduction?

[qjerome]

I just have my huge project requiring some setup ... I would need to figure out how to repro the issue on a small repository but I have not the time for this right now !

[qjerome]

I tried to build a minimal repro project for several hours but in vain ... Yet I do still have the error even with the latest version of r-a.
The link to my project, where I have the issue is: https://github.com/kunai-project/kunai

The particularities of that project that may trigger the error above are the following:

• a cargo workspace running on Rust stable toolchain
• a rust-analyzer.linkedProjects running on nightly Rust because it needs a custom target only available in nightly
• several cargo related tasks are actually handled by a custom xtask: such as clippy, build, run ... (see cargo xtask -h for details)

I hope this will help you ...