title: Flutter: Build ios error : ld: 13 duplicate symbols for architecture x86_64
body: <p>After some trouble to add Geolocator plugin and couldn't work. I removed Geolocator from pubspec.yaml but now the project couldnt build for ios.
  I have tried for 2 days without success including:</p>
  
  <ol>
  <li>Change Flutter channel</li>
  <li>Flutter upgrade</li>
  <li>Pod deintegrate</li>
  <li>Delete the xcode project files</li>
  <li>added 'config.build_settings['SWIFT_VERSION'] = '4.1'</li>
  <li><p>and many more I cant remember now.</p>
  
  <p>duplicate symbol _OBJC_IVAR_$_MDMPasscodeCache._localAuthenticationInfo in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeCache_f189776e75765630b82721fafea64052.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeCache_42de90102bb6814d03833694aafcc99d.o)
  duplicate symbol _OBJC_IVAR_$_MDMPasscodeCache._keychainInfo in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeCache_f189776e75765630b82721fafea64052.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeCache_42de90102bb6814d03833694aafcc99d.o)
  duplicate symbol _OBJC_IVAR_$_MDMPasscodeCache._hasLocalAuthentication in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeCache_f189776e75765630b82721fafea64052.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeCache_42de90102bb6814d03833694aafcc99d.o)
  duplicate symbol _OBJC_IVAR_$_MDMPasscodeCache._hasKeychain in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeCache_f189776e75765630b82721fafea64052.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeCache_42de90102bb6814d03833694aafcc99d.o)
  duplicate symbol _OBJC_IVAR_$_MDMPasscodeCache._cachedState in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeCache_f189776e75765630b82721fafea64052.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeCache_42de90102bb6814d03833694aafcc99d.o)
  duplicate symbol _OBJC_IVAR_$_MDMPasscodeCache._keychainExpireTime in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeCache_f189776e75765630b82721fafea64052.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeCache_42de90102bb6814d03833694aafcc99d.o)
  duplicate symbol _OBJC_CLASS_$_MDMPasscodeCache in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeCache_f189776e75765630b82721fafea64052.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeCache_42de90102bb6814d03833694aafcc99d.o)
  duplicate symbol _OBJC_METACLASS_$_MDMPasscodeCache in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeCache_f189776e75765630b82721fafea64052.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeCache_42de90102bb6814d03833694aafcc99d.o)
  duplicate symbol _OBJC_IVAR_$_MDMPasscodeCache._hasEnteredBackground in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeCache_f189776e75765630b82721fafea64052.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeCache_42de90102bb6814d03833694aafcc99d.o)
  duplicate symbol _OBJC_IVAR_$_MDMPasscodeState._status in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeState_d2697588db599ad1e82d46f342216cee.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeState_adbe96d99863168799049cc0f0164c6d.o)
  duplicate symbol _OBJC_IVAR_$_MDMPasscodeState._info in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeState_d2697588db599ad1e82d46f342216cee.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeState_adbe96d99863168799049cc0f0164c6d.o)
  duplicate symbol _OBJC_CLASS_$_MDMPasscodeState in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeState_d2697588db599ad1e82d46f342216cee.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeState_adbe96d99863168799049cc0f0164c6d.o)
  duplicate symbol _OBJC_METACLASS_$_MDMPasscodeState in:
  /Volumes/flutter/ios/Pods/GoogleMobileVision/Detector/Frameworks/GoogleMobileVision.framework/GoogleMobileVision(MDMPasscodeState_d2697588db599ad1e82d46f342216cee.o)
  /Volumes/flutter/ios/Pods/GoogleSignIn/Frameworks/GoogleSignIn.framework/GoogleSignIn(MDMPasscodeState_adbe96d99863168799049cc0f0164c6d.o)
  ld: 13 duplicate symbols for architecture x86_64
  clang: error: linker command failed with exit code 1 (use -v to see invocation)</p></li>
  </ol>
  
  <p>Now, I am at loss on how to resolve this.</p>
  
  <p>UPDATE:
  Now I have new errors after deleting and reinstalling CocoaPods:</p>
  
  <p>Analyzing dependencies
  Fetching podspec for <code>Flutter</code> from <code>.symlinks/flutter/ios</code>
  Fetching podspec for <code>cloud_firestore</code> from <code>.symlinks/plugins/cloud_firestore/ios</code>
  Fetching podspec for <code>connectivity</code> from <code>.symlinks/plugins/connectivity/ios</code>
  Fetching podspec for <code>firebase_admob</code> from <code>.symlinks/plugins/firebase_admob/ios</code>
  Fetching podspec for <code>firebase_analytics</code> from <code>.symlinks/plugins/firebase_analytics/ios</code>
  Fetching podspec for <code>firebase_auth</code> from <code>.symlinks/plugins/firebase_auth/ios</code>
  Fetching podspec for <code>firebase_core</code> from <code>.symlinks/plugins/firebase_core/ios</code>
  Fetching podspec for <code>firebase_messaging</code> from <code>.symlinks/plugins/firebase_messaging/ios</code>
  Fetching podspec for <code>firebase_storage</code> from <code>.symlinks/plugins/firebase_storage/ios</code>
  Fetching podspec for <code>flutter_native_image</code> from <code>.symlinks/plugins/flutter_native_image/ios</code>
  Fetching podspec for <code>google_sign_in</code> from <code>.symlinks/plugins/google_sign_in/ios</code>
  Fetching podspec for <code>image_picker</code> from <code>.symlinks/plugins/image_picker/ios</code>
  Fetching podspec for <code>native_device_orientation</code> from <code>.symlinks/plugins/native_device_orientation/ios</code>
  Fetching podspec for <code>package_info</code> from <code>.symlinks/plugins/package_info/ios</code>
  Fetching podspec for <code>path_provider</code> from <code>.symlinks/plugins/path_provider/ios</code>
  Fetching podspec for <code>qr_mobile_vision</code> from <code>.symlinks/plugins/qr_mobile_vision/ios</code>
  Fetching podspec for <code>share</code> from <code>.symlinks/plugins/share/ios</code>
  Fetching podspec for <code>url_launcher</code> from <code>.symlinks/plugins/url_launcher/ios</code>
  [!] CocoaPods could not find compatible versions for pod "Firebase/AdMob":
    In Podfile:
      firebase_admob (from <code>.symlinks/plugins/firebase_admob/ios</code>) was resolved to 0.0.1, which depends on
        Firebase/AdMob</p>
  
  <p>Specs satisfying the <code>Firebase/AdMob</code> dependency were found, but they required a higher minimum deployment target.
  CocoaPods could not find compatible versions for pod "GoogleUtilities/AppDelegateSwizzler":
    In Podfile:
      firebase_admob (from <code>.symlinks/plugins/firebase_admob/ios</code>) was resolved to 0.0.1, which depends on
        Firebase/AdMob was resolved to 5.8.0, which depends on
          Firebase/Core (= 5.8.0) was resolved to 5.8.0, which depends on
            FirebaseAnalytics (= 5.1.2) was resolved to 5.1.2, which depends on
              GoogleUtilities/AppDelegateSwizzler (~> 5.2.0)</p>
  
  <p>Specs satisfying the <code>GoogleUtilities/AppDelegateSwizzler (~&gt; 5.2.0)</code> dependency were found, but they required a higher minimum deployment target.
  CocoaPods could not find compatible versions for pod "gRPC-Core":
    In Podfile:
      cloud_firestore (from <code>.symlinks/plugins/cloud_firestore/ios</code>) was resolved to 0.0.1, which depends on
        Firebase/Firestore was resolved to 5.8.0, which depends on
          FirebaseFirestore (= 0.13.3) was resolved to 0.13.3, which depends on
            gRPC-C++ (~> 0.0.3) was resolved to 0.0.3, which depends on
              gRPC-C++/Implementation (= 0.0.3) was resolved to 0.0.3, which depends on
                gRPC-Core (= 1.14.0)</p>
  
  <pre><code>cloud_firestore (from `.symlinks/plugins/cloud_firestore/ios`) was resolved to 0.0.1, which depends on
    Firebase/Firestore was resolved to 5.8.0, which depends on
      FirebaseFirestore (= 0.13.3) was resolved to 0.13.3, which depends on
        gRPC-ProtoRPC (~&gt; 1.0) was resolved to 1.14.1, which depends on
          gRPC-ProtoRPC/Main (= 1.14.1) was resolved to 1.14.1, which depends on
            gRPC (= 1.14.1) was resolved to 1.14.1, which depends on
              gRPC/Main (= 1.14.1) was resolved to 1.14.1, which depends on
                gRPC-Core (= 1.14.1)
  </code></pre>