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I have two frameworks in my project, each of which depend on the same Swift package (in this case RxSwift, but I don't think that's important).

To get the project to build I've had to include the same package in both targets (via the "Frameworks and Libraries" list in the target's General settings) - otherwise when I try to import the package it can't find it.

When I run my app I see warnings in the console like:

objc[79287]: Class _TtC9Alamofire18UploadTaskDelegate is implemented in both

/Users/deanWombourne/Desktop/PackageManagerTest/DerivedData/PackageManagerTest/
Build/Products/Debug-iphonesimulator/Framework1.framework/Framework1 (0x110877e00)

and

/Users/deanWombourne/Library/Developer/CoreSimulator/Devices/2319A320-1A01-4784-B85E-272FF0F999CB/
data/Containers/Bundle/Application/D40DE3EA-DD78-4241-B307-070CDAF8BFA1/PackageManagerTest.app/PackageManagerTest (0x10f9858c8).

One of the two will be used. Which one is undefined.

and, sometimes, the app crashes in the package which is duplicated.

I've tested the app by building a version without the duplicate package issue (copy/paste all code into the same target!) and it runs fine then, so this is something to do with the duplicate package issue.

So, what's my question?

Is there any way in Xcode to specify that a single package will be included in two targets, but not to just copy it twice into the executable?

I'd ideally like to specify it as a dynamic library of some sort so it's not baked into the executable at all but is loaded on demand - but any solution is welcome at this point!

EDIT

I also get this issue if I have only one framework but it shares the RxSwift package dependency with the main app target.

deanWombourne
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  • It would seem that you are explicitly linking the packages to the frameworks when building them. Are you by chance embedding the package in both? Typical method for cases like this is to not link up against them and then have the final target link against everything needed. There is some other trickery one can do if you have to include it such as hiding the package. I've done that in the C/C++ realm, so can't fully vouch that last one can be done with Swift. – Mobile Ben Sep 25 '19 at 20:51
  • Thats exactly what's happening - but I can't see any way of getting it to work without doing that in Xcode. Ideally I would want the build process to recognise I'm including this library in two targets and just include it once in the final executable - but it doesn't seem to understand how to do that! If I try your approach of manually linking it into the main binary once, I get linker errors when I try to build the two frameworks. – deanWombourne Sep 26 '19 at 08:39

1 Answers1

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How I resolved the issue in XCode 11 for RxSwift package:

  1. Add the RxSwift package as a dependency to your project (you probably already did it)

  2. Create a new framework target (I called it 'RxSwiftDependency'). You don't need to add any files or anything else to it. Leave it as it was created.

  3. On General tab for that additional target add the swift-package dependency in 'Frameworks and Libraries' section (see screenshot below)

  4. Add that additional target (RxSwiftDependency) to the 'Frameworks and Libraries' of the targets that need the dependency. And remove 'RxSwift' if you added it before.

  5. In .swift files of other targets that need RxSwift entities add 'import RxSwift'

  6. Embed all necessary frameworks in the final target

Screenshot1

Aleksei Kolchanov
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