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This post is auto-generated from RSS feed The Rust Programming Language Forum - Latest topics. Source: Rust Analyzer in VSCode: "Cannot create expander" for macros error Unsupported metadata version 10

I'm using a couple of Rust macros in a relatively simple Rust CLI application. First, the tokio::main macro, and secondly, the strum::Display and strum::EnumIter macros. The former allows my main function to be async, and the latter two allow me to convert enum variants to/from string values, to provide user interaction.

• Windows 11
• Rust beta toolchain 1.88.0-beta.6 (873a06493 2025-05-10)
• VSCode 1.101.1
• Rust Analyzer extension for VSCode 0.3.2500

I'm getting an error on the code blocks that are utilizing macros, the main function definition, and the enum definition.

I can build and run the application perfectly fine, using cargo run.

I used the Rust-Analyzer: Restart Server option in VSCode, and that seems to have cleared up the issue for now. Is this a common issue that other people have come across, and shouldn't the extension be able to resolve this error without manually restarting it?

Does anyone know why I would get these errors in the first place?

NOTE: I am NOT doing any cross-compilation. I am either building natively on Windows 11 or using Docker Desktop to build a Linux (WSL2) container image, but that's it. There's no cross-compilation with the Rust toolchain.

tokio::main: Cannot create expander for ...\target\debug\deps\tokio_macros-cf9cdf6be2c8bed0.dll: unsupported metadata version 10
Cannot create expander for ...\target\debug\deps\strum_macros-509b7d3669cad3f0.dll: unsupported metadata version 10

#[tokio::main]
async fn main() {
    loop {
        let _ = select_function().await;
    }
} 

#[derive(strum::Display, EnumIter)]
enum UserOperation {
    #[strum(to_string = "Category 1: Operation 01")]
    Cat1Op1,
    #[strum(to_string = "Category 1: Operation 02")]
    Cat1Op2,
}

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