Address issue with handle::cast<bool>(), quench warning in example 12 (fixes #110)
diff --git a/example/example12.cpp b/example/example12.cpp
index 7bba2c8..ab1b482 100644
--- a/example/example12.cpp
+++ b/example/example12.cpp
@@ -54,6 +54,7 @@
             Example12,
             run_bool
         );
+        throw std::runtime_error("this will never be reached");
     }
 
     virtual void pure_virtual() {