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Fixed in 2020.2.X

Fixed in 2018.4.X, 2019.4.X, 2020.1.X



Found in




Issue ID




[iOS] using Xcode recommended settings throws "This function declaration is not a prototype" warnings when deploying the App



Reproduction steps:
1. Create an empty project
2. Switch the platform to iOS
3. Build the project and open it in Xcode
4. Go to warnings tab in Xcode
5. Press on "Update to recommended settings" warning
6. Press "Perform Changes" in the window that appeared
7. Try deploying the project to an iOS device and inspect the warnings tab

Unexpected behaviour: thousands of "This function declaration is not a prototype" warnings are thrown

Reproducible with: 2018.4.22f1, 2020.2.0a13

Tested with Xcode Versions 11.4.1 (11E503a), 11.3.1 (11C504)

Couldn't test with tvOS build because switching to recommended settings removes deployment targets

1. The deployed Application seems to work fine
2. The user suggested a workaround: Replacing () with (void) in the function prototypes resolves the warnings
3. A video is attached

  1. Resolution Note (fix version 2020.2):

    We have fixed the -Wstrict-prototypes warning, but there are other warnings in Xcode's "recommended settings" that will still be triggered by IL2CPP generated code so some errors are still expected when using recommended settings in Xcode.
    Fixed in: 2020.2.0a17

  2. Resolution Note (fix version 2020.1):

    Fixed in 2020.1.5f1.4487

  3. Resolution Note (fix version 2019.4):

    Fixed in 2019.4.10f1 (d9ef6fd7d683)

  4. Resolution Note (fix version 2018.4):

    Fixed in 2018.4.27f1 (4e283b7d3f88)

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