Warning regarding private macro use on Rust 1.79

[gschulze]

I am getting the following warning on recent Rust versions. Although not an error, it would be nice to export the macro properly in a future release.

warning: macro Error is private
--> path/to/file.rs:40:10
|
| #[derive(Error, Debug)]
| ^^^^^
|
= warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
= note: for more information, see issue #120192 rust-lang/rust#120192
= note: #[warn(private_macro_use)] on by default

[dtolnay]

The macro is exported properly in thiserror. The warning you got is probably related to a use in some other crate in your dependency graph, but you haven't shared a way to reproduce it.