Getting proc macro not expanded: No proc-macros present for crate rust-analyzer (unresolved-proc-macro) on macos

[kt390256]

rust-analyzer version: rust-analyzer version: v0.3.1799 (https://github.com/rust-lang/rust-analyzer/commit/9db515503f11bda7812cdfb9c2839f70f4cb1fdd 2024-01-01)

OS: MacOS 14.2.1 (23C71)

rustc version: rustc 1.75.0 (82e1608df 2023-12-21)

relevant settings: none

Any effort will be appreciated!

[Veykril]

Have you tried clearing your target dir? I've seen this error happen when upgrading my toolchain from time to time (not quite sure why that error specifically happens then).

Also check the logs maybe some error is in there.

[Systemcluster]

I'm seeing the same error since ~2 weeks ago with Rust nightly (currently rustc 1.77.0-nightly (6ae4cfbbb 2024-01-17)). Deleting the target directory doesn't help. It occurs on two different systems (Windows and macOS).

In my case it errors on a #[cfg_attr(feature = "std", derive(thiserror::Error))] with proc macro 'feature' not expanded: No proc-macros present for crate at feature = "std", in this codebase.

There's no output in the "Rust Analyzer Language Server" logs.

[stjepangolemac]

Also happening to me when deriving clap::Parser in the Helix editor. There's nothing interesting in the logs.

[Veykril]

There has been a breaking change in cargo afaik that breaks package ids which cargo metadata does not handle correctly. This should be fixed by the next rustc nightly. see rust-lang/cargo#13311

[martinlindhe]

Thanks, @Veykril. I had this too for a little while, and updating nightly to rustc 1.77.0-nightly (88189a71e 2024-01-19) fixes it for me.

[installgentoo]

This now happens in 1.78