Command CompileAssetCatalog failed with a nonzero exit code

I managed to resolve this by doing a "build clean", removing "DerivedData" folder and re-starting my Mac.

It seems that this occurs if you change one of the images opened from the Assets. Here are some solutions that worked:

1. Run the app on a different simulator
2. Clean (both CMD+SHIFT+K and CMD+ALT+SHIFT+K)
3. Re-add the Assets into the project
4. Restart Mac
5. JOKE: Restart the electric power plant

Try removing and then re-adding some of the files you're using. That did it for me at least.

This seems to be a bug in the Xcode 10.1

Make sure that you have an AppIcon file in your assets. I had the same error because I did deleted that file.