Repro:
- Xcode 9.3 beta
- iOS 11.3 beta 2
- Add ARReferenceImages to Assets.xcassets following documentation here
- Compile
Results in: error: Exception while running actool: ...
Looks like a bug in Xcode where the deployment target also has to be 11.3 to use ARReferenceImages with asset catalogs.
Fix: Change deployment target to 11.3
Adding a Named color (New color set) to the asset catalog will workaround this error.