Problem building with Swift 5.8 and higher

[amotl]

Hi there.

First things first: Thanks a stack for conceiving this excellent library. We are currently observing problems building it on Swift 5.8 and higher due to an obstacle with swift-async-algorithms.

• Swift 5.8 compilation failure /Package.swift:4:8: error: no such module 'CompilerPluginSupport' -> ⚠️ SemVer break apple/swift-async-algorithms#349

We've discovered it when whipping up documentation about how to connect from Swift to CrateDB, which is a distributed database providing a PostgreSQL-compatible interface.

• Patch: Driver: Add page about Swift crate/cratedb-guide#413
• Preview: https://cratedb-guide--413.org.readthedocs.build/connect/swift.html

With kind regards,
Andreas.

[amotl]

Like outlined over at apple/swift-async-algorithms#349 (comment), as a workaround, we are building the application using Swift 5.7 now.

docker run --rm -it --volume=$(pwd):/src --network=host swift:5.7 bash

Maybe you can spot where we are doing anything wrong that prevents building with Swift 5.8 and higher?

[gwynne]

Swift 5.8 and 5.9 are not supported by PostgresKit in the first place, and I've already worked up a PR to drop 5.10 support as well and require 6.0. Additionally, since you've identified your problem as an issue with a downstream dependency, swift-async-algorithms, which is not only not required by this package but not even required by any package this package directly requires, it is unclear what you expect PostgresKit to do about it.

Also, looking at the bug you filed on swift-async-algorithms, your problem appears not to be that your Swift is too new, but that it's too old. Swift 5.8 is quite outdated; the current release version of Swift is 6.2. Please consider trying to build with something a little newer.

[amotl]

Hi Gwynne. After switching to Swift >=6.0, everything works fluently. Thanks a stack for your swift reply, supporting us as absolute beginners with Swift.

// swift-tools-version:6.0

• https://cratedb-guide--413.org.readthedocs.build/connect/swift.html