2016-01-22.md

Subteam report: lang 2016-01-22

Highlights

We've decided to accept two RFCs this week, RFC 1320 and RFC 1462. Both are small tweaks to existing RFCs. We decided to extend the FCP period for RFC 243 (try and ?) because there was still some ongoing discussion. That's it!

-- nmatsakis

Dashboard

RFC phase

• PR #197: ManuallyDrop type gives precise control of dtors of inline data.
• PR #1062: Constants that depend on type parameters in generic code
• PR #1148: Mutually exclusive traits
• PR #1177: Anonymous/placeholder lifetime "'_".
• PR #1180: Propose Interior<T> data-type, to allow moves out of the dropped value during the drop hook.
• PR #1201: Add support for naked functions.
• PR #1210: RFC: impl specialization
• PR #1248: Safe intrinsics RFC
• PR #1258: Add macros to get the values of configuration flags
• PR #1303: Add a let...else expression, similar to Swift's guard let...else
• PR #1305: Abstract output type parameters
• PR #1319: Amend RFC1228 with operator fixity and precedence
• PR #1321: Unstable visibility RFC
• PR #1327: Dropck Eyepatch RFC.
• PR #1346: Unsafe expressions
• PR #1358: RFC: Add #[repr(align = "N")]
• PR #1373: Remove some kinds of doc comments
• PR #1379: Change thread local variables to only accept async-signal-safe types.
• PR #1398: Allocators, take III
• PR #1399: RFC: Add #[repr(pack = "N")]
• PR #1406: Rfc: delegation of implementation
• PR #1408: Delayed resolution
• PR #1414: Add Rvalue-static-promotion RFC
• PR #1422: pub(restricted) item
• PR #1426: Placement in/box refinement
• PR #1429: Feature gate extern fn methods
• PR #1431: Statically dispatched methods for trait objects with associated data
• PR #1437: ESC byte escape
• PR #1440: RFC - Allow Drop types in statics/const functions
• PR #1444: RFC: native C-compatible unions via built-in syntax macro union!
• PR #1445: Restrict constants in patterns
• PR #1449: Add language support for bitfields
• PR #1450: Types for enum variants
• PR #1459: Add a used attribute
• FCP PR #243: Trait-based exception handling
• FCP PR #1129: IndexAssign: overloading the a[b] = c expression
• FCP PR #1196: RFC for allowing eliding more type parameters.
• FCP PR #1296: RFC: Add an alias attribute to #[link] and -l
• FCP PR #1320: Amend 1192 (RangeInclusive) to use an enum.
• FCP PR #1462: Add [ to the FOLLOW(ty) in macro future-proofing rules.

Implementation phase

• Issue #13231: opt-in built-in bounds traits RFC tracker
• Issue #15552: Implement lifetime elision
• Issue #16293: Implement UFCS (Tracking RFC 132)
• Issue #17307: Implement associated items
• Issue #18469: Implement revised coercion rules
• Issue #21939: Tracking issue for Finalize defaulted type parameters (RFC 213)
• Issue #22020: Tracking issue for Integer Overflow (RFC 560)
• Issue #22181: box and in expressions (tracking issue for RFC 809)
• Issue #23416: Type ascription (tracking issue for RFC 803)
• Issue #24263: discriminant_value intrinsic -- tracking issue for 639
• Issue #27060: repr(packed) allows invalid unaligned loads
• Issue #27336: Tracking Issue for RFC 213: Default Type Parameter Fallback

High priority issues

• Issue #22889: Duplicate inherent static methods can be defined in separate impl blocks
• Issue #25860: Implied bounds on nested references + variance = soundness hole
• Issue #26775: extern crate is always treated as pub within the crate, but is not visible outside it; pub extern crate makes no difference
• Issue #28514: Private trait's methods reachable through a public subtrait
• Issue #29149: Lifetime bounds in Copy impls are ignored
• Issue #29859: Cyclic traits allow arbitrary traits to be synthesized
• Issue #30127: Desugared x.index(y) is not equivalent to x[y]
• Issue #30346: Re-add raw_pointer_derive lint as a no-op

Needs decision

• Issue #21232: borrow-checker allows partial reinit of struct that has been moved away, but no use of it.
• Issue #23818: print! macro should flush stdout