cargo classpath configuration doesn't work?

[nikomatsakis]

I've setup a .config/cargo.toml that sets the classpath, but when I run

cargo run --example logger

it doesn't seem to be set. I don't understand why and that's confusing. HELP!

[fpoli]

I think it's a cache invalidation issue with procedural macros that depend on environment variables: rust-lang/rust#74690.

I tried actually reading CLASSPATH instead of using the hardcoded java for javap. The result is that modifying the CLASSPATH in .cargo/config does not trigger a recompilation of the example, but after a cargo clean duchess uses the modified classpath.

[nikomatsakis]

Ah, @fpoli, that's perhaps right. Is there a "correct way" to fix this?

[fpoli]

The correct fix seems to be rust-lang/rust#99515, but in the meantime #35 should work fine.