Swift error while starting app, after update to Xcode 10.2 beta 3

Question

After updating Xcode to 10.2 beta 3, I receive this error while starting app, which will result in crash (app compiles successfully):

objc[2140]: Swift class extensions and categories on Swift classes are not allowed to have +load methods (lldb)

Do you know what this may be due to?

Answer 1

In my case, it is because I added a module which uses Swift to my ReactNative project. In this issue they discussed this bug and there were several solutions.

The official solution is to upgrade RN to 0.59.3+, but it may influence too much for me and I would not to do that for now, so I edited RCTBridgeModule.h according to this commit as a workaround and it works.

Answer 2

Some of your dependencies can have +load methods. In my case, there were Firebase and Swinject cocoapods.