Accepted answer

only one way to solve this issue.

  1. Quit Xcode.
  2. Delete project's temp files located at ~/Library/Developer/Xcode/DerivedData
  3. Delete ProjectName.xcworkspace
  4. Delete Podfile.lock file and Pods folder
  5. Run pod install.
  6. Open the newly created ProjectName.xcworkspace file and build.

one way to solve this issue.

  1. Quit Xcode.
  2. Delete project's temp files located at ~/Library/Developer/Xcode/DerivedData
  3. Delete ProjectName.xcworkspace
  4. Delete Podfile.lock file and Pods folder
  5. Run pod install.
  6. Open the newly created ProjectName.xcworkspace file and build.

Check your podfile:

platform :ios, '11.0'

Then in XCode "Build Settings" , choose

iOs Deployment Target: 11.0

worked for me:

  • rm -rf project.xcworkspace
  • rm -rf ~/Library/Developer/Xcode/DerivedData
  • rm -rf Podfile.lock
  • pod install

/!\ Open project.xcworkspace instead of your old file

 issue was simple. I have a new m1 mac and it has trouble loading cocoa pods sometimes. Simply:

  • Click your pods project(blue pods)->
  • Click all & build settings ->
  • Excluded architectures ->
  • add "arm64" to both debug and release ->
  • set any SDK on left side ->
  • do this on your main project folder too ->
  • build it your good to go

follow below steps:

  1. Quite xcode
  2. Delete "ProjectName.xcworkspace", "Podfile.lock" and "Pods".
  3. Delete project's temp files located at ~/Library/Developer/Xcode/DerivedData (Command + Shift + G in finder)
  4. Run "pod install" from terminal.
  5. Open "ProjectName.xcworkspace".
  6. Add "$(inherited)" to "TARGET > Build Settings > Framework Search Paths".

using Swift 4 and Xcode 9. All I have to do is selecting FirebaseCore Scheme.

On Xcode:

Product->Scheme->FirebaseCore.

If you don't have FirebaseCore go to Manage Schemes and select it. Then try again.

Build ( + B) worked for me.