Firebase-ios-sdk: [RemoteConfig] Apple Mach-O Linker Error (using pods)

[augusto-carmo]

• Xcode version: 9.4.1 (9F2000)
• Firebase SDK version: 4.13.0
• Firebase Component: RemoteConfig
• Component version: 4.13.0

---

The problem

The project is not compiling after I have added the Firebase/RemoteConfig to my project (It worked when I tried to compile only the Firebase/Core).

Xcode throws 10 errors:

Full Log (click to expand)

Ld /Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Products/Debug-iphonesimulator/MyProject.app/MyProject normal x86_64
    cd /Users/my_user/Documents/SolProjects/iOSMyProject/MyProject
    export IPHONEOS_DEPLOYMENT_TARGET=9.0
    export PATH="/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin:/Applications/Xcode.app/Contents/Developer/usr/bin:/usr/local/bin:/usr/bin:/bin:/usr/sbin:/sbin"
    /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/clang -arch x86_64 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator11.4.sdk -L/Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Products/Debug-iphonesimulator -F/Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Products/Debug-iphonesimulator -F/Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Products/Debug-iphonesimulator/Alamofire -F/Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Products/Debug-iphonesimulator/AlamofireImage -F/Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Products/Debug-iphonesimulator/DZNEmptyDataSet -F/Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Products/Debug-iphonesimulator/ImageScrollView -F/Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Products/Debug-iphonesimulator/PocketSVG -F/Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Products/Debug-iphonesimulator/SQLite.swift -F/Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Products/Debug-iphonesimulator/SwiftProtobuf -F/Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Products/Debug-iphonesimulator/lottie-ios -F/Users/my_user/Documents/SolProjects/iOSMyProject/MyProject -filelist /Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Intermediates.noindex/MyProject.build/Debug-iphonesimulator/MyProject.build/Objects-normal/x86_64/MyProject.LinkFileList -Xlinker -rpath -Xlinker @executable_path/Frameworks -Xlinker -rpath -Xlinker @loader_path/Frameworks -Xlinker -rpath -Xlinker @executable_path/Frameworks -mios-simulator-version-min=9.0 -dead_strip -Xlinker -object_path_lto -Xlinker /Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Intermediates.noindex/MyProject.build/Debug-iphonesimulator/MyProject.build/Objects-normal/x86_64/MyProject_lto.o -Xlinker -export_dynamic -Xlinker -no_deduplicate -Xlinker -objc_abi_version -Xlinker 2 -fobjc-link-runtime -L/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/lib/swift/iphonesimulator -Xlinker -add_ast_path -Xlinker /Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Intermediates.noindex/MyProject.build/Debug-iphonesimulator/MyProject.build/Objects-normal/x86_64/MyProject.swiftmodule -framework Alamofire -framework AlamofireImage -framework DZNEmptyDataSet -framework ImageScrollView -framework Lottie -framework PocketSVG -framework SQLite -framework SwiftProtobuf -Xlinker -sectcreate -Xlinker __TEXT -Xlinker __entitlements -Xlinker /Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Intermediates.noindex/MyProject.build/Debug-iphonesimulator/MyProject.build/MyProject.app-Simulated.xcent -framework FirebaseCore -framework Pods_MyProject -framework Protobuf -framework Protobuf -framework YouTubePlayer -framework FirebaseRemoteConfig -framework FirebaseABTesting -Xlinker -dependency_info -Xlinker /Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Intermediates.noindex/MyProject.build/Debug-iphonesimulator/MyProject.build/Objects-normal/x86_64/MyProject_dependency_info.dat -o /Users/my_user/Library/Developer/Xcode/DerivedData/MyProject-fdkhsolhvqanmkgeavdyagnuwpow/Build/Products/Debug-iphonesimulator/MyProject.app/MyProject

Undefined symbols for architecture x86_64:
  "_OBJC_CLASS_$_GPBDescriptor", referenced from:
      objc-class-ref in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      objc-class-ref in FirebaseABTesting(ExperimentPayload.pbobjc_4e1beb4a76b519334457d2edc68ca6a8.o)
  "_OBJC_CLASS_$_GPBEnumDescriptor", referenced from:
      objc-class-ref in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      objc-class-ref in FirebaseABTesting(ExperimentPayload.pbobjc_4e1beb4a76b519334457d2edc68ca6a8.o)
  "_GPBGetMessageInt32Field", referenced from:
      _ABTExperimentPayload_OverflowPolicy_RawValue in FirebaseABTesting(ExperimentPayload.pbobjc_4e1beb4a76b519334457d2edc68ca6a8.o)
  "_OBJC_METACLASS_$_GPBMessage", referenced from:
      _OBJC_METACLASS_$_RCNPackageData in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_METACLASS_$_RCNKeyValue in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_METACLASS_$_RCNNamedValue in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_METACLASS_$_RCNConfigFetchRequest in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_METACLASS_$_RCNPackageTable in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_METACLASS_$_RCNAppNamespaceConfigTable in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_METACLASS_$_RCNAppConfigTable in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      ...
  "_GPBSetInt32IvarWithFieldInternal", referenced from:
      _SetABTExperimentPayload_OverflowPolicy_RawValue in FirebaseABTesting(ExperimentPayload.pbobjc_4e1beb4a76b519334457d2edc68ca6a8.o)
  "_OBJC_CLASS_$_GPBMessage", referenced from:
      _OBJC_CLASS_$_RCNPackageData in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_CLASS_$_RCNKeyValue in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_CLASS_$_RCNNamedValue in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_CLASS_$_RCNConfigFetchRequest in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_CLASS_$_RCNPackageTable in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_CLASS_$_RCNAppNamespaceConfigTable in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_CLASS_$_RCNAppConfigTable in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      ...
  "_OBJC_METACLASS_$_GPBRootObject", referenced from:
      _OBJC_METACLASS_$_RCNConfigRoot in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_METACLASS_$_ABTExperimentPayloadRoot in FirebaseABTesting(ExperimentPayload.pbobjc_4e1beb4a76b519334457d2edc68ca6a8.o)
  "_OBJC_CLASS_$_GULAppEnvironmentUtil", referenced from:
      objc-class-ref in FirebaseRemoteConfig(RCNConfigSettings_22e23cfa4b36fa0d65a3f7296e546bb7.o)
      objc-class-ref in FirebaseRemoteConfig(RCNDevice_b34010fb0ab3a3316b3c7f3a7a1f6525.o)
  "_GULLoggerRegisterVersion", referenced from:
      ___FIRLoggerInitializeASL_block_invoke in FirebaseCore(FIRLogger.o)
  "_OBJC_CLASS_$_FIRInstanceID", referenced from:
      objc-class-ref in FirebaseRemoteConfig(RCNConfigFetch_818a3e7a84a8883f210a714bb3ad1fe5.o)
  "_OBJC_CLASS_$_GPBFileDescriptor", referenced from:
      objc-class-ref in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      objc-class-ref in FirebaseABTesting(ExperimentPayload.pbobjc_4e1beb4a76b519334457d2edc68ca6a8.o)
  "_GULLoggerInitializeASL", referenced from:
      ___FIRLoggerInitializeASL_block_invoke in FirebaseCore(FIRLogger.o)
  "_GULLoggerForceDebug", referenced from:
      ___FIRLoggerInitializeASL_block_invoke in FirebaseCore(FIRLogger.o)
  "_OBJC_CLASS_$_GPBRootObject", referenced from:
      _OBJC_CLASS_$_RCNConfigRoot in FirebaseRemoteConfig(Config.pbobjc_3cb2eac75751d3cd2757df0f7544c9e9.o)
      _OBJC_CLASS_$_ABTExperimentPayloadRoot in FirebaseABTesting(ExperimentPayload.pbobjc_4e1beb4a76b519334457d2edc68ca6a8.o)
  "_GULLogBasic", referenced from:
      _FIRLogBasic in FirebaseCore(FIRLogger.o)
  "_GULLoggerEnableSTDERR", referenced from:
      ___FIRLoggerInitializeASL_block_invoke in FirebaseCore(FIRLogger.o)
  "_GULIsLoggableLevel", referenced from:
      _FIRIsLoggableLevel in FirebaseCore(FIRLogger.o)
  "_GULSetLoggerLevel", referenced from:
      _FIRSetLoggerLevel in FirebaseCore(FIRLogger.o)
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)

---

Podfile (click to expand)

platform :ios, '9.0'
use_frameworks!  

target 'MyProject' do
    pod 'ImageScrollView'
    pod 'DZNEmptyDataSet'
    pod 'Alamofire'
    pod 'AlamofireImage'
    pod 'SQLite.swift'
    pod 'SwiftProtobuf'
    pod 'lottie-ios'
    pod 'PocketSVG'
    pod 'Firebase', '4.13.0'
    pod 'Firebase/RemoteConfig', '4.13.0'
end

target 'Protobuf' do
    pod 'SwiftProtobuf'
end

---

Podfile.lock (click to expand)

PODS:
  - Alamofire (4.6.0)
  - AlamofireImage (3.3.0):
    - Alamofire (~> 4.5)
  - DZNEmptyDataSet (1.8.1)
  - Firebase (4.13.0):
    - Firebase/Core (= 4.13.0)
  - Firebase/Core (4.13.0):
    - FirebaseAnalytics (= 4.2.0)
    - FirebaseCore (= 4.0.20)
  - Firebase/RemoteConfig (4.13.0):
    - Firebase/Core
    - FirebaseRemoteConfig (= 2.1.3)
  - FirebaseABTesting (1.0.0):
    - FirebaseCore (~> 4.0)
    - Protobuf (~> 3.1)
  - FirebaseAnalytics (4.2.0):
    - FirebaseCore (~> 4.0)
    - FirebaseInstanceID (~> 2.0)
    - "GoogleToolboxForMac/NSData+zlib (~> 2.1)"
    - nanopb (~> 0.3)
  - FirebaseCore (4.0.20):
    - "GoogleToolboxForMac/NSData+zlib (~> 2.1)"
  - FirebaseInstanceID (2.0.10):
    - FirebaseCore (~> 4.0)
  - FirebaseRemoteConfig (2.1.3):
    - FirebaseABTesting (~> 1.0)
    - FirebaseAnalytics (~> 4.1)
    - FirebaseCore (~> 4.0)
    - FirebaseInstanceID (~> 2.0)
    - "GoogleToolboxForMac/NSData+zlib (~> 2.1)"
    - Protobuf (~> 3.5)
  - GoogleToolboxForMac/Defines (2.1.4)
  - "GoogleToolboxForMac/NSData+zlib (2.1.4)":
    - GoogleToolboxForMac/Defines (= 2.1.4)
  - ImageScrollView (1.4)
  - lottie-ios (2.1.5)
  - nanopb (0.3.8):
    - nanopb/decode (= 0.3.8)
    - nanopb/encode (= 0.3.8)
  - nanopb/decode (0.3.8)
  - nanopb/encode (0.3.8)
  - PocketSVG (2.4.0)
  - Protobuf (3.6.0)
  - SQLite.swift (0.11.5):
    - SQLite.swift/standard (= 0.11.5)
  - SQLite.swift/standard (0.11.5)
  - SwiftProtobuf (1.0.2)

DEPENDENCIES:
  - Alamofire
  - AlamofireImage
  - DZNEmptyDataSet
  - Firebase (= 4.13.0)
  - Firebase/RemoteConfig (= 4.13.0)
  - ImageScrollView
  - lottie-ios
  - PocketSVG
  - SQLite.swift
  - SwiftProtobuf

SPEC REPOS:
  https://github.com/cocoapods/specs.git:
    - Alamofire
    - AlamofireImage
    - DZNEmptyDataSet
    - Firebase
    - FirebaseABTesting
    - FirebaseAnalytics
    - FirebaseCore
    - FirebaseInstanceID
    - FirebaseRemoteConfig
    - GoogleToolboxForMac
    - ImageScrollView
    - lottie-ios
    - nanopb
    - PocketSVG
    - Protobuf
    - SQLite.swift
    - SwiftProtobuf

SPEC CHECKSUMS:
  Alamofire: f41a599bd63041760b26d393ec1069d9d7b917f4
  AlamofireImage: 2e784dc5d00f04903a52c1d169181469c805c3df
  DZNEmptyDataSet: 9525833b9e68ac21c30253e1d3d7076cc828eaa7
  Firebase: 5ec5e863d269d82d66b4bf56856726f8fb8f0fb3
  FirebaseABTesting: d07d0ee833b842d5153549e4c7e2e2cb1c23a3f9
  FirebaseAnalytics: 7ef69e76a5142f643aeb47c780e1cdce4e23632e
  FirebaseCore: 90cb1c53d69b556f112a1bf72b5fcfaad7650790
  FirebaseInstanceID: 8d20d890d65c917f9f7d9950b6e10a760ad34321
  FirebaseRemoteConfig: 3e95fb7c072308492e85fa41d59d38b3d6fd2372
  GoogleToolboxForMac: 91c824d21e85b31c2aae9bb011c5027c9b4e738f
  ImageScrollView: 887523542097173da75172774e9800ee473bdccd
  lottie-ios: 836cdbba92f62f3c6a00e37a4ce485321fe317cf
  nanopb: 5601e6bca2dbf1ed831b519092ec110f66982ca3
  PocketSVG: 8ac7b20a881ca1a3d46ba1e54ee2b0f2307c3d48
  Protobuf: 0fc0ad8bec688b2a3017a139953e01374fedbd5f
  SQLite.swift: 6e5356850bb1791459f8c16d6ee9195b28714a2e
  SwiftProtobuf: e41d205c91eac0fb46823f2561712407fefdaf4e

PODFILE CHECKSUM: c7284bed023fe73a94b4a6390eb29f15477a8101

COCOAPODS: 1.5.3

---

I have already tried a bunch of stuff to try to solve this problem, but nothing worked out 🙁.

Thanks in advance ;)

[paulb777]

It looks like you have a mix of Firebase 4.x and 5.x pods.

Did you run pod install instead of pod update?

Is there any reason for locking to version 4.13.0 versus using the latest Firebase?

[augusto-carmo]

@paulb777, I also tried to use the latest Firebase version. Setting it to an old one was an attempt to see if it was a latest release issue. There was no reason at all to lock at 4.13.0.

I tried running pod install several times, but with no success =/.

It looks like you have a mix of Firebase 4.x and 5.x pods.

I did not understand that very well. How can I assure that I will use only one version?

Thank you very much for your reply :D

---

🆕 _I have just added the Podfile.lock to my first post._

[augusto-carmo]

I have been doing new attempts since the last post and I could find the root cause of the problem: the Protobuf module that I use in my project (it uses SwiftProtubf pod). I could solve the problem by removing the module and moving all of its content to the main module.

What I would like to know is if is there any way to keep the Protobuf files in a separate module and still be able to compile and run the project?

I tried using abstract_target, but it did not work =/

Cheers o/

[paulb777]

Yeah, the pods in the 'MyProject' target work fine for me whether I pin Firebase to 4.13.0 or not.

It is likely to be related specifically to the implementation of the Protobuf target in the Xcode project. I'm not sure what you mean by "module". Do you mean Xcode target? How does Protobuf relate to MyProject?

We likely need a reproducible to example to help further. Also, since this seems to be more of an iOS app structure question than a Firebase issue, stackoverflow might be a better venue to expose the question to a broader set of potential answerers.

[augusto-carmo]

Hello, @paulb777!

One of my colleagues made an attempt where he renamed the _target_ Protobuf and the problems seems to have been solved. So, it looks like that all of those errors were being thrown due to target names conflict(?) - _this may explain why I could not find many people having the same problem while I was looking for a solution on the Internet, it is a very specific problem_.

Thank you very much for your attention and your time \o/.

I'll close the issue as long as everything is ok now 🎉

[ristinolla]

Hi,

Although this is closed issue, have anyone seen this when installing the SDK manually (not using Cocoapods)? Or how to actually achieve @augusto-carmo's idea of renaming the Protobuf to something else?

I just downloaded the newest SDK 5.6.0 and the problem still persists. Using the same Xcode version (9.4.1).

Thanks for any help on where to look next!

[ristinolla]

Never mind, it was propably something else in my Xcode setup... Did the following and builds now fine:

• Uninstalling the SDK and linking
• emptying Derived Data folder in ~/Library/Developer/Xcode/DerivedData
• restarting xcode
• installing the the SDK again

[augusto-carmo]

Hello, @ristinolla, every now and than, when I have to switch branches and they use different pods, I am required to empty the _Derived Data_ folder, so xCode does not warn me of any errors. For your next branch switches and pod install, only that step might do it :)

[ristinolla]

Thanks, @augusto-carmo for the tip, I'll keep in the mind that _Derived Data_ is something to remember to clean every now and then.

[stickfaith]

I also encountered this error, it can be solved by import GoogleUtilities.framework，

[ghost]

Thanks @stickfaith . Adding that framework solved the problem.