Firebase Warnings

Versions

Firebase (5.5.0) and Google-Mobile-Ads (7.31.0)

Following discussion here: firebase/firebase-ios-sdk#196 (comment)

Reproduction steps:

1. Clone this repo
2. Open FirebaseWarnings.xcworkspace with Xcode 9.4.1 or 9.3.x
3. Choose Generic iOS Device next to the scheme dropdown
4. On the menu, run Product --> Archive
5. View the build logs and notice ~133 warnings that look like the below

Showing All Issues
ld: warning: Linker asked to preserve internal global: 'sharedInstance.sharedInstance'
ld: warning: Linker asked to preserve internal global: '__block_descriptor_tmp'
ld: warning: Linker asked to preserve internal global: '__block_literal_global'
``