conversion-gen: Better error on duplicate objects

staging/src/k8s.io/code-generator/cmd/conversion-gen/generators/conversion.go

@@ -175,7 +175,7 @@ func getManualConversionFunctions(context *generator.Context, pkg *types.Package
 			key := conversionPair{inType.Elem, outType.Elem}
 			// We might scan the same package twice, and that's OK.
 			if v, ok := manualMap[key]; ok && v != nil && v.Name.Package != pkg.Path {
-				panic(fmt.Sprintf("duplicate static conversion defined: %s -> %s", key.inType, key.outType))
+				panic(fmt.Sprintf("duplicate static conversion defined: %s -> %s from:\n%s.%s\n%s.%s", key.inType, key.outType, v.Name.Package, v.Name.Name, f.Name.Package, f.Name.Name))
 			}
 			manualMap[key] = f
 		} else {