framework not found FirebaseAnalytics

I had the same error, my Framework Search Paths in Build Settings were already set to $(inherited) for both Debug and Release.

I managed to solve this with the solution here: https://stackoverflow.com/a/38246169/1092815

In other words, Podfile.lock had some bad versions in it, running this solved the my issue:

pod update
pod install

You are probably using cocoapods to add Firebase. Make sure that in the build settings for your target the 'Framework Search Paths' both for Debug and Release start with $(inherited).

The build settings for your pod dependencies are defined in a xcconfig file, if you don't have $(inherited) in your target's build settings, the settings from this file will be ignored.