RUSTSEC-2026-0173: proc-macro-error2 is unmaintained

> proc-macro-error2 is unmaintained

| Details | |
| ------------------- | ---------------------------------------------- |
| Status | unmaintained |
| Package | `proc-macro-error2` |
| Version | `2.0.1` |
| URL | [https://github.com/GnomedDev/proc-macro-error-2/issues/17](https://github.com/GnomedDev/proc-macro-error-2/issues/17) |
| Date | 2026-06-07 |

The author of `proc-macro-error2` has [confirmed](https://github.com/GnomedDev/proc-macro-error-2/issues/17#issuecomment-4643215473) that the crate is no longer maintained and recommends that users migrate away from it.

`proc-macro-error2` was originally created as a maintained fork of [`proc-macro-error`](https://crates.io/crates/proc-macro-error) (see [RUSTSEC-2024-0370](https://rustsec.org/advisories/RUSTSEC-2024-0370)). Both the original crate and this fork are now unmaintained.

## Possible Alternative(s)

- [manyhow](https://crates.io/crates/manyhow)
- [proc-macro2-diagnostics](https://github.com/SergioBenitez/proc-macro2-diagnostics)

See [advisory page](https://rustsec.org/advisories/RUSTSEC-2026-0173.html) for additional details.

Search the repository manifests and source for uses of `proc-macro-error2`, then inspect the affected macro code and dependency configuration. Compare the migration options listed in the advisory and verify the project’s tests and checks after the unmaintained crate is no longer used.

Written by the indexing model from the issue text.