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Fixed in 2020.1.X

Fixed in 2019.3.X



Found in


Issue ID




[iOS] `Swift Language Version` is not set in Xcode Build Settings when a .swift source plugin is added to an Unity Project



To Reproduce:

1. Add a valid .swift source file to your Unity project and mark it as an iOS plugin.
2. Export and Xcode project and build it.
3. Observe that Xcode fails with:

The target "Unity-iPhone" contains source code developed with Swift 3.x. This version of Xcode does not support building or migrating Swift 3.x targets.

(or something similar)

This happens because we don't set the "Swift Language Version" (SWIFT_VERSION)" field to any Swift version in our build post-processor.

Tested on:

Comments (4)

  1. tonythedad

    Jul 19, 2020 23:23

    Never been fixed for me it months.

    Build target UnityFramework of project Unity-iPhone with configuration ReleaseForRunning
    error: Invalid SWIFT_VERSION: Could not parse version component from: '0 5' (in target 'UnityFramework' from project 'Unity-iPhone')

    Xcode 11.6
    Unity 2019.4.2f1

  2. Lex3425

    Apr 25, 2020 19:14

    I've come to experience the problem in 2019.3.5.f1 also. However, it seems like it has been fixed now. Errors like these are not massive but can be frustrating and are what we look to avoid on any of our websites like Glad to see this has been addressed and fixed.

  3. rendermouse

    Mar 16, 2020 14:19

    I am experiencing this on 2019.3.5.f1 as well.

  4. excalith

    Feb 22, 2020 10:51

    Still broken on 2019.3.1f1 and 2019.3.2f2. Used to build with 2019.3.1f1 but started to fail. Seems like something is breaking this

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