diff --git a/Diffusion/Pipeline/PipelineLoader.swift b/Diffusion/Pipeline/PipelineLoader.swift
index 8d1c190..34b51c2 100644
--- a/Diffusion/Pipeline/PipelineLoader.swift
+++ b/Diffusion/Pipeline/PipelineLoader.swift
@@ -104,6 +104,8 @@ extension PipelineLoader {
         case .cpuAndGPU         : return .original
         case .cpuAndNeuralEngine: return .splitEinsum
         case .all               : return .splitEinsum
+        @unknown default:
+            fatalError("Unknown MLComputeUnits")
         }
     }