Linker hardening, Git merge cleanup, and language pitches

Linker safety and version-control workflow drew the heaviest review, with a binutils series against heap corruption in ELF relaxation and two Git patches for branch cleanup and shallow fetches. Swift, Python, Haskell, and LLVM also moved proposals on function types, ABI back-deployment, async C APIs, and target-feature queries.

Binutils hardens ELF relaxation against size underflow

A v3 patch series hardens 18 BFD ELF backends against memmove underflow and heap corruption when the linker deletes bytes during in-place relaxation. The series is under discussion on the binutils list. It matters because the failure mode is memory corruption in a component used by essentially every ELF link.

Swift pitches called-once function types

A second pitch proposes @once and @atMostOnce function types so closures can carry noncopyable and non-Sendable values. The Swift forums thread has drawn a wide set of reviewers. The types would give the language a typed way to express single-use closures instead of relying on conventions.

Git patch would delete squash-merged branches

A patch series adds --delete-integrated, extending --delete-merged, so branch deletion can detect squash and rebase merges by file content rather than commit reachability. The series is under active review on the Git list. Teams that squash-merge would get a way to prune integrated branches that today's reachability check misses.

Swift considers back-deployment for fixed-layout types

The Swift core team pitches extending @backDeployed to fixed-layout value types, so types such as Span and Ref can run on older runtimes through metadata uniquing. The proposal is on the Swift forums. Library authors who need newer value types on older OS releases are the audience.

Git fetch option would limit shallow clones

A patch series under review adds a fetchRefmap config and --limited-fetch so a shallow repository need not fetch every branch. The thread is the largest of the day on the Git list. CI jobs and developer checkouts that use shallow clones would avoid ref traffic they do not use.

Haskell Foundation outlines an ecosystem vision

The Haskell Foundation TLC says it is operational and shares a technical vision plus a lightweight proposal process for funded initiatives. Discussion is on the Haskell discourse. The note is governance rather than a compiler change, but it sets how funded ecosystem work will be proposed.

PEP 852 would add async functions to Python's C API

The author presents PEP 852 for async and await support in the C API. A small thread covers callback signatures and error handling. Extension authors who need to drive coroutines from C are the ones who should follow it.

LLVM RFC proposes a post-inlining target-feature query

An RFC proposes an llvm.target.feature.enabled intrinsic so front ends can ask, at compile time after inlining, which target features are enabled. Rust and Julia are named as intended users. Compiler writers who specialize code after inlining would get a defined query instead of ad hoc checks.