Crash when trying to run with Hummingbird library install on iOS 15 and 16

[adamjansch]

Hi there,

We're looking to integrate Hummingbord into our iOS app which has a minimum iOS version of 15.0. After adding the Hummingbird package to the app via SPM we get a crash on launch when using either a physical device or simulator running iOS 15 or 16:

Console printout:

dyld[451]: Library not loaded: '/usr/lib/swift/libswift_StringProcessing.dylib'
Referenced from: '/private/var/containers/Bundle/Application/BB106B5F-470B-4B5F-846E-D2313B287437/App.app/App'
Reason: tried: '/usr/lib/system/introspection/libswift_StringProcessing.dylib' (no such file), '/usr/lib/swift/libswift_StringProcessing.dylib' (no such file), '/usr/local/lib/libswift_StringProcessing.dylib' (no such file), '/usr/lib/libswift_StringProcessing.dylib' (no such file)

This is before we've added any Hummingbird-specific code to the app.

I understand that Hummingbird is intended for iOS 17+, but our minimum iOS is non-negotiable and we were hoping to use @available/#available in our code to allow its use for devices that meet that requirement. Is there any chance of a fix?

[adam-fowler]

Unfortunately Hummingbird makes use of APIs unavailable prior to iOS 17.
I don't know why it is trying to drag in the StringProcessing library though we don't use Regex anywhere.

[adamjansch]

I understand that, but using Swift's @available and #available attributes allows an Xcode project with a lower minimum iOS version to still include a library that uses APIs available only in later iOS versions.

[adam-fowler]

I think this may be a limitation of Xcode and swift packages where the package regardless of whether sections of it are used or not will link all the standard library components. I'm not certain but perhaps the swift version, or minimum platform indicates what will be linked.

[adamjansch]

I'm going to fork and take a swing at it, will let know what I find.

[adam-fowler]

I'm going to fork and take a swing at it, will let know what I find.

What you could do is remove the platform requirement from Hummingbird Package.swift and add it inside the hummingbird code instead.

[adamjansch]

What you could do is remove the platform requirement from Hummingbird Package.swift and add it inside the hummingbird code instead.

That's actually what I ended up doing, and that has eliminated the crash on iOS 15/16.

Is that a change you'd be happy with if I cooked up a PR? I understand if not, as it does add a little bit of noise to the codebase; we can run from my fork and pull in updates when required.

[adam-fowler]

No I'd be happy with a PR. Checkout valkey-swift for a way to do availability aliases