main でも release/6.2 でも修正済みなのでチェックアウトされている swift-syntax のコミットが進めばそのうち消えると思います． https://github.com/swiftlang/swift-syntax/pull/3002

Fix build warnings by ahoppen · Pull Request #3002 · swiftlang/sw...

Mostly, ensure that we only use @_implementationOnly if we build with RESILIENT_LIBRARIES. Also, strerror is marked as unsafe and deprecated on Windows. It looks like this is because strerror is no...