Tracking issue for RFC 3458: Unsafe fields

[traviscross]

This is a tracking issue for:

• Unsafe fields rfcs#3458

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

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

• Approve as lang experiment.
• Accept an RFC.
  • Unsafe fields rfcs#3458
• Implement in nightly.
  • Implement the unsafe-fields RFC. #132915
  • Do not implement unsafe auto traits for types with unsafe fields #133934
  • Make Copy unsafe to implement for ADTs with unsafe fields #134008
  • Add rustfmt support
    • https://github.com/rust-lang/rust/pull/132915/changes#diff-0dcb8600bb02d5401c2bc27003c6f272b3376ef57154ebbe2f813955cf4fc904
  • Add clippy::missing_safety_doc support
    • Extend clippy::missing_safety_doc to unsafe fields rust-clippy#16767
  • Add rustdoc support
• Add documentation to the dev guide.
  • See the instructions.
• Add documentation to the reference.
  • See the instructions.
• Add formatting for new syntax to the style guide.
  • See the nightly style procedure.
• Stabilize.
  • See the instructions.

Unresolved Questions

• If the syntax for restrictions does not change, what is the ordering of keywords on a field that is both unsafe and mut-restricted?

Related

TODO.

cc @jswrenn @veluca93 @jhpratt @rust-lang/lang

[traviscross]

@rustbot labels +I-lang-nominated

Tracking issue created and nominated due to the request for a lang experiment here:

• Unsafe fields rfcs#3458 (comment)

[traviscross]

We talked about this in our lang triage call today and approved this as an experiment. @joshtriplett is particularly enthusiastic about this work and is willing to liaison.