Fatbobman’s Swift Weekly #046 | Warning-Free Compilation is Not the Ultimate Goal of Swift 6

Weekly Comment

Warning-Free Compilation is Not the Ultimate Goal of Swift 6

Recently, I began refactoring one of my apps, with full Swift 6 support being a key consideration. During this process, I first attempted to achieve perfect compilation for my self-built third-party libraries in Swift 6 mode.

The code in these libraries isn’t complex, and after some adjustments, most could compile without warnings in Swift 6 mode. However, this result didn’t particularly please me. Reviewing the modified code, I realized that the changes were more about appeasing the compiler rather than approaching concurrency safety challenges from a holistic design perspective with a fresh viewpoint.

Swift 6 attempts to preemptively mitigate risks in complex multi-threaded environments through stricter compiler checks. While the compiler can provide considerable assistance to developers, we shouldn’t overly rely on these safety prompts. Instead, we should rethink how to construct code structures that not only meet compilation requirements but are truly safe and reliable, based on a deep understanding of Swift’s new concurrency tools.