Duplicate symbol errors with Firebase iOS SDK v5.5.0+

[andwun]

After upgrading Firebase iOS SDK from v5.4.1 to v5.5.0 or later, duplicate symbol errors make my builds fail:

duplicate symbol _pb_field_iter_next in:
    /Users/redacted/Library/Developer/Xcode/DerivedData/redacted-fajkgspepnsyukaipdzoafipxkmd/Build/Products/Debug-iphonesimulator/nanopb/libnanopb.a(pb_common.o)
    /Users/redacted/Documents/Code/redacted/iOS/Pods/GoogleAppMeasurement/Frameworks/GoogleAppMeasurement.framework/GoogleAppMeasurement(pb_common_072e976572d290cdb35c7ac508302b94.o)
[...]
ld: 30 duplicate symbols for architecture x86_64

I'm using Cocoapods to integrate Firebase. use_frameworks! is not used.

From analyzing Podfile.lock, the dependency tree looks like:

• Firebase/Core
  • FirebaseAnalytics
    • nanopb
    • GoogleAppMeasurement
      • nanopb

... so this seems much like a Firebase-internal problem.

Does this mean use_frameworks! is now required to use the SDK?
If so, it would be helpful to have this mentioned in the docs and release notes.

Environment

• Xcode version: 9.4.1 and 10.0 GM
• Firebase SDK version: Good: 5.4.1, Bad: 5.5.0
• Cocoapods version: 1.5.3

[paulb777]

CocoaPods should ensure there is only one version of pb_common.o. I suspect the problem is from cruft in DerivedData between Firebase version updates. Does rm -rf ~/Library/Developer/Xcode/DerivedData help? If you're still stuck, please share the Podfile and Podfile.lock.

[Piramanayagamm]

I am also facing the same problem. Removing DerivedData is not helping out. Here is my Pod file

target 'XXX' do
pod 'UIColor+Hex'
pod 'AFNetworking', '> 2.6.3'
pod 'AFNetworkActivityLogger', '> 2.0'
pod 'Lockbox', '> 2.1.0'
pod 'libextobjc', '> 0.4'
pod 'Mantle', '1.5.4'
pod 'ReactiveCocoa', '> 2.0'
pod 'RSSwizzle', '> 0.1.0'
pod 'GoogleTagManager', '3.15.0'
pod 'UrbanAirship-iOS-SDK', '8.6.0'
pod 'TOCropViewController', '2.2'
pod 'UICountingLabel', '~> 1.4.0'
pod 'Fabric', '1.7.2'
pod 'Crashlytics', '3.9.3'
pod 'OptimizelySDKiOS','2.1.0'
pod 'Firebase/Core'
end

[ryanwilson]

@Piramanayagamm can you please share your Podfile.lock as well so we can see what versions each pod resolved to? Thanks!

[paulb777]

We reproduced this yesterday and the fix will be in the upcoming Firebase 5.9.0 release. Internally tracked at b/116139404

Two possible workarounds:

• Use use_frameworks! in the Podfile
• Remove -all_load from the Other Linker Flags Build Setting