[Bug] Unity + Firebase Analytics iOS Deadlock+crash on start

[Inspyro]

[REQUIRED] Please fill in the following fields:

• Unity editor version: 2019.3.18f1
• Firebase Unity SDK version: 8.3.0
• Source you installed the SDK: .unitypackage (.unitypackage or Unity Package Manager)
• Problematic Firebase Component: Analytics(Auth, Database, etc.)
• Other Firebase Components in use: None (Auth, Database, etc.)
• Additional SDKs you are using: Facebook, Admob (Facebook, AdMob, etc.)
• Platform you are using the Unity editor on: Windows (Mac, Windows, or Linux)
• Platform you are targeting: iOS (iOS, Android, and/or desktop)
• Scripting Runtime: IL2CPP(Mono, and/or IL2CPP)

[REQUIRED] Please describe the issue here:

Add Firebase SDK to Unity, build and upload build to testflight
Download and install the build on iOS device
App immediately hangs (before unity splash screen is shown) on some devices (e.g. iPhone 7)
App crashes after around 10s of hangs

Steps to reproduce:

Repro rate: 100%

See attached crashlog from Testflight
testflight_feedback.zip

[paulinon]

Hi @Inspyro,

Thanks for reporting this issue. Upon checking your crash logs, it seems that there's nothing related to Firebase. Could you confirm if the app crashes without the use of TestFlight? Could you also confirm if the app crashes with just the Firebase SDK?

[Inspyro]

The app only crashes when including the Firebase SDK. It does also crash when starting it directly with xCode.
When removing the firebase unity sdk, the app does not crash.

The crash has GoogleUtilities in it - so i would assume it is either admob or firebase - and there definitely must be some interoperability issue

As a workaround we are including the Firebase iOS SDK ourselves (directly in xCode) - this works without a problem
Maybe the unity admob + unity firebase sdk are not compatible with each other?

[DellaBitta]

Hi @Inspyro,

When you don't include the Firebase SDK could you note with podfiles the Unity AdMob SDK installs for iOS? There could be a version mismatch with the Firebase SDK iOS dependencies.

Thanks!