Tracking Issue for RFC 3325: unsafe attributes

[traviscross]

This is a tracking issue for RFC 3325: unsafe attributes

• unsafe attributes rfcs#3325

The feature gate for the issue is #![feature(unsafe_attributes)].

About tracking issues

Tracking issues are used to record the overall progress of implementation. They are also used as hubs connecting to other relevant issues, e.g., bugs or open design questions. A tracking issue is however not meant for large scale discussion, questions, or bug reports about a feature. Instead, open a dedicated issue for the specific matter and add the relevant feature gate label.

Steps

• Accept the RFC.
  • unsafe attributes rfcs#3325
• Implement in nightly Rust 2024.
  • Parse unsafe attributes #124214
  • TODO: PR to add this to Rust 2024 itself.
• Implement migration lints.
• N/A: Add documentation to the dev guide.
  • See the instructions.
• Add documentation to the reference.
  • See the instructions.
• Add documentation to the edition guide.
• Add formatting for new syntax to the style guide.
  • See the nightly style procedure.
• Ensure ready for Rust 2024 stabilization.

Unresolved Questions

• Different lint staging. The lint on using existing unsafe attributes like no_mangle outside unsafe(...) could be staged in various ways: it could be warn-by-default to start or we wait a while before to do that, it could be edition-dependent, it might eventually be deny-by-default or even a hard error on some editions -- there are lots of details here, which can be determined later during the process.

Implementation history

• Parse unsafe attributes #124214

cc @RalfJung @carbotaniuman @rust-lang/style

This issue has been assigned to @carbotaniuman via this comment.

[traviscross]

@rustbot assign @carbotaniuman

@carbotaniuman has volunteered to own this item to get it over the line for the edition. Huge thanks for that.

[traviscross]

@rustbot labels +I-style-nominated

There's probably not a lot for T-style to do here, but strictly speaking, this is a kind of new syntax, so it may be worth at least a short discussion for visibility.