Tracking issue for RFC 3722: Explicit ABIs in `extern`

[traviscross]

This is a tracking issue for:

• [RFC] Explicit ABI in extern rfcs#3722

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

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 an RFC.
  • [RFC] Explicit ABI in extern rfcs#3722
• Add migration lint.
  • Improve missing_abi lint #132357
• Make and FCP the change to warn-by-default in all editions.
  • Make missing_abi lint warn-by-default. #132397
• Make this a hard error in the next edition on nightly under a feature flag.
  • Blocked on finalizing the name and timing of the next edition.
  • Add explicit_extern_abis Feature and Enforce Explicit ABIs #135340
• 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 on nightly on the next edition.
  • See the instructions.

Unresolved Questions

None.

Related

TODO.

Implementation history

TODO.

[obeis]

I have started working on implementing the RFC, and I will probably address a PR in the next two weeks.

[compiler-errors]

Is this not already implemented as the MISSING_ABI lint? cc @m-ou-se

[m-ou-se]

Yes, it is already implemented as a lint.

I assume this tracking issue is for making it a hard error in the next edition?

[compiler-errors]

Yeah, I just wanted @obeis and @traviscross to be aware that this functionality is already implemented. It would be nice to have a PR to set it to deny in the new edition and implements a migration, though that is also dependent on a PR that adds the new edition (2027).

[m-ou-se]

I already added a machine applicable suggestion to the lint, so the migration part is already done. The lint just needs to be added to the edition migration lint group at some point

[traviscross]

The tracking issue steps above are now updated with the relevant work.