December 14, 2024:

• Swift 6.0 and Language Mode: Swift language development is now focused on three major areas - making Swift Concurrency easier to approach and adopt, providing low-level language and library tools for high-performance and constrained environments, and improving language interoperability (especially with C++ and Java).
• Swift Concurrency Challenges: The Swift 6 language mode provides a base for Swift Concurrency, but many developers find it difficult to adopt. The Language Steering Group (LSG) is considering ideas to ease this burden and has written about it in the prospective vision for approachable concurrency.
• Avoiding Copies and Restricted Values: The LSG is interested in improving Swift's facilities for avoiding copies and working safely with restricted values. Implementors are working on Span types and features to allow borrowing values. This will improve performance and enable Swift in more constrained environments.
• Safe Interoperation with C++: Swift's support for non-copyable and non-escaping types will help reason about C++ functions and ensure correct usage, making it easier to use C++ from Swift with greater confidence and cleaner code.
• Direct Interoperation with Java: There is a new project to allow Swift to directly interoperate with Java using a more library-oriented solution based on reading and writing Swift interfaces.

December 14, 2024 (ibex10):

• Documentation and communicating sequential processes: The biggest difficulty is the lack of unified, coherent documentation with examples for real-world problems. There is also a lack of direct support for communicating sequential processes, but optimism remains for improvement in the near future.

December 14, 2024 (Karl):

• Ownership SSA: Since low-level performance is a focus, the question is whether full enabling of Ownership SSA is included. In code inspection, sometimes the optimiser doesn't eliminate certain copies. The @Michael\_Gottesman described Ownership SSA in his LLVM talk as a new lowering that preserves ownership information and is better at eliminating unnecessary copies. Currently, for non-stdlib libraries, it gets stripped partway through the optimiser. The expectation is to enable it by default in the coming year and raise the bar for optimiser-eliminated copies.

December 15, 2024 (Andrew\_Trick):

• -Xfrontend -enable-ossa-modules: This mode is a focus this year and enables optimization of copies across module boundaries, as seen in the Array example. There is more work to fully utilize OSSA, but it is an important step.