When Duplicate Symbol _OBJC_CLASS_ Appears in Large Numbers During iOS App Build

When encountering a large number of duplicate symbol _OBJC_CLASS_ errors during an iOS app build

After updating CocoaPods and building the project, I encountered a linker error. Upon examining the message, I noticed a large number of duplicate symbol _OBJC_CLASS_$_ errors.

→ Check the project's Build Settings → Other Linker Flags.

-ObjC
-l"Pods-AFNetworking"
-l"Pods-MBProgressHUD"
-l"Pods-SDWebImage"
-all_load
...

Remove all instances of -l"Pods-library name".

-ObjC
-all_load
...

It should look like this.

Build the project. → OK