Rust Edition 2024

Milestones

September 2023:

• Formally petition the Leadership Council to form the Edition 2024 Working Group
  • https://github.com/rust-lang/leadership-council/issues/55
• Start Edition RFC
  • https://github.com/rust-lang/rfcs/pull/3501

October 2023:

• Preliminary roadmap with rough dates.
• Merge Edition RFC
• Draft a blog post to call the community to action in proposing features for the 2024 edition
• Start adding preliminary support for Edition 2024 in all tools provided by the Rust project
  • rustc: https://github.com/rust-lang/rust/pull/94461
  • cargo: https://github.com/rust-lang/cargo/pull/12771
  • rustfmt: https://github.com/rust-lang/rust/pull/94461
    • They are in the process of adding the 2024 "style edition". https://github.com/rust-lang/rustfmt/pull/5787 and related PRs.
  • clippy: https://github.com/rust-lang/rust/pull/94461
  • rust-analyzer: https://github.com/rust-lang/rust-analyzer/pull/16151

November 2023:

• Blog post letting people know about the edition and the schedule
• Ask teams to check this document and add things (or confirm that they will not be making any edition changes)
  • compiler
  • lang
  • libs
  • rustdoc
  • cargo
  • style

December 2023:

• Pre-RFCs should be posted.

January 2024:

• RFCs should be posted.

February 2024:

• Final list of changes. All proposed changes have:
  • An approved RFC
  • Migration+idiom lint plan
  • Partial implementation or plan for implementation

March 2024:

April 2024:

May 2024:

• All proposed changes implemented and available in nightly.

June 2024:

• All lints implemented on nightly and tested on crater.

July 2024:

• Announce start of public testing.

August 2024:

• Finish marketing materials, docs, etc.
  • Blog post(s)
  • Edition guide
• Stabilize --edition=2024 on nightly (1.82), any time between 2024-08-01 and 2024-08-31.

September 2024:

October 2024:

• --edition=2024 available on stable in Rust 1.82 on 2024-10-17.

Tentative features of the new edition

rustdoc

• Turn INVALID_DOC_ATTRIBUTES lint into a hard error
  • [ ] proposed Appears to no longer be an edition change.

Libs

• Include Future and IntoFuture in the 2024 prelude
  • Proposed https://github.com/rust-lang/rfcs/pull/3509
  • Approved https://github.com/rust-lang/rfcs/pull/3509#issuecomment-1906495817
  • implemented https://github.com/rust-lang/rust/pull/121041
  • autofixable ? https://github.com/rust-lang/rust/issues/121042#issuecomment-1942181209
    • Nilstrieb working on this
  • documented https://doc.rust-lang.org/nightly/edition-guide/rust-2024/prelude.html (partially complete)
• Remove RustcEncodable & RustcDecodable from prelude in next edition
  • proposed https://github.com/rust-lang/libs-team/issues/272
  • approved https://github.com/rust-lang/rust/pull/116016#issuecomment-1937145162
  • implemented https://github.com/rust-lang/rust/pull/116016
    • internal unstable bug: https://github.com/rust-lang/rust/issues/123156
  • autofixable https://github.com/rust-lang/rust/pull/116016#issuecomment-1937153238
  • documented https://github.com/rust-lang/edition-guide/pull/298

Lang

https://github.com/rust-lang/lang-team/blob/HEAD/src/roadmaps/roadmap-2024.md
https://github.com/rust-lang/lang-team/issues/209
https://github.com/rust-lang/rust/labels/lang-team-202x-edition
https://github.com/orgs/rust-lang/projects/43/views/2

• Change unsafe_op_in_unsafe_fn to be warn-by-default
  • proposed https://rust-lang.github.io/rfcs/2585-unsafe-block-in-unsafe-fn.html
  • approved https://github.com/rust-lang/rust/issues/71668#issuecomment-1189396860
  • implemented https://github.com/rust-lang/rust/pull/112038
  • autofixable https://github.com/rust-lang/rust/pull/119948
  • documented
    • edition guide https://doc.rust-lang.org/nightly/edition-guide/rust-2024/unsafe-op-in-unsafe-fn.html
    • reference
  • Overlapping suggestions https://github.com/rust-lang/rust/issues/123304
  • Crater run https://github.com/rust-lang/rust/pull/122960
• Reserve gen keyword.
  • proposed https://github.com/rust-lang/rfcs/pull/3513
  • approved https://github.com/rust-lang/rfcs/pull/3513#issuecomment-1957166202
    • Concerns over picking a different keyword instead of gen? https://github.com/rust-lang/rust/issues/117078
  • implemented https://github.com/rust-lang/rust/pull/116447
  • autofixable https://github.com/rust-lang/rust/pull/123680
  • documented
    • edition guide
    • reference
• RPIT Lifetime Capture
  • proposed https://github.com/rust-lang/rfcs/pull/3498
  • approved
  • implemented
    • https://github.com/rust-lang/rust/pull/116952
    • TAIT or precise capturing? https://github.com/rust-lang/rust/issues/117587
      • @TC indicated that stabilizing TAIT is a prerequisite for providing a way to express precise capturing. #63063
  • autofixable
  • documented
    • edition-guide
    • reference
• Macro matcher fragment specifier policy
  • approved https://rust-lang.github.io/rfcs/3531-macro-fragment-policy.html
  • implemented / autofixable N/A
  • docs (Add to edition-guide?)
• Disallow reference to static mut
  • approved https://github.com/rust-lang/rust/issues/114447#issuecomment-1707177536
  • implemented https://github.com/rust-lang/rust/pull/117556
    • Should this also include "hidden" references?
      • https://github.com/rust-lang/rust/issues/123060
      • https://github.com/rust-lang/rust/issues/114447#issuecomment-1837156804
      • https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/static_mut_refs/near/427198395
  • autofixable — current lint is maybe-incorrect, uncertain if there is a migration plan
    • https://github.com/rust-lang/rust/issues/123061
  • documented
    • edition guide https://doc.rust-lang.org/nightly/edition-guide/rust-2024/static-mut-reference.html (partially complete)
    • Get help: https://rust-lang.zulipchat.com/#narrow/stream/213817-t-lang/topic/static_mut_refs
      • https://github.com/rust-lang/rust/issues/123059
    • reference
• New range types
  • proposed https://github.com/rust-lang/rfcs/pull/3550
    • Crater data collected, waiting on lang?
  • approved https://github.com/rust-lang/rfcs/pull/3550#issuecomment-1908544755
• Temporary lifetimes in tail expressions
  • proposed
• Unprefixed string literals
  • proposed https://github.com/rust-lang/rfcs/pull/3593
  • approved https://github.com/rust-lang/rfcs/pull/3593#issuecomment-2017640953
  • implemented
  • autofixable
  • documented
    • edition guide
    • reference
• Unsafe attributes
  • proposed https://github.com/rust-lang/rfcs/pull/3325
  • approved https://github.com/rust-lang/rfcs/pull/3325#issuecomment-1396911253
  • implemented
  • documented
• Unsafe extern
  • proposed https://github.com/rust-lang/rfcs/pull/3484
  • approved https://github.com/rust-lang/rfcs/pull/3484#issuecomment-2023097397
  • implemented
  • documented

Cargo

https://github.com/orgs/rust-lang/projects/30/views/1

• Remove implicit features

  • proposed https://rust-lang.github.io/rfcs/3491-remove-implicit-features.html
  • approved https://github.com/rust-lang/rfcs/pull/3491#issuecomment-1739937122
  • implemented
    • https://github.com/rust-lang/cargo/pull/13621
  • autofixable
  • documented

• Public/private dependencies

  • proposed https://rust-lang.github.io/rfcs/3516-public-private-dependencies.html
  • approved https://github.com/rust-lang/rfcs/pull/3516#issuecomment-1777514797
  • implemented Partially implemented, see tracking issue https://github.com/rust-lang/rust/issues/44663
    • Waiting on rustc rework from davidtwco
  • autofixable
  • documented

• MSRV-dependent resolver

  • proposed https://rust-lang.github.io/rfcs/3537-msrv-resolver.html
  • approved https://github.com/rust-lang/rfcs/pull/3537#issuecomment-1899285746
  • implemented Under development, see tracking: https://github.com/rust-lang/cargo/issues/9930
  • autofixable
  • documented

Rustfmt

• implement style edition

  • https://github.com/rust-lang/rustfmt/pull/5787
  • https://github.com/rust-lang/rustfmt/pull/5854
  • https://github.com/rust-lang/rustfmt/pull/5937

• Enable overflow_delimited_expr by default

  • proposed
  • approved https://github.com/rust-lang/rust/pull/114764#issuecomment-1826417341
  • implemented

• Use version sort

  • proposed
  • approved https://github.com/rust-lang/rust/pull/115046
  • implemented

• Unicode-aware sort

  • proposed
  • approved https://github.com/rust-lang/rust/pull/115046

• Miscellaneous rustfmt bugfixes?

  • What is this?
  • proposed
  • approved https://github.com/rust-lang/rust/pull/113394