Linker command failed with exit code 1 after installing CocoaPods and firebase pod

I got stuck for awhile trying to solve this, but the solution turned out to be very easy :)
If you are using Cocoapods in your project, one needs to use xcworkspace to build instead of xcproject. If you are using Cocoapods and build from  xcproject , it will ignore the Cocoapods libraries you need.

Sometimes its because of you might be declaring an object with same variable name.

Clear the repeating variable name change it. After that clean your project and build again. Its worked for me....! Thanks.

I faced the same problem for hours and solved it with a simple hack. Just do clean and then Build