Applied Stefan's fix regarding missing 'break' statements in units.c

src/units.c

@@ -320,9 +320,15 @@ void units_get_base_unit_exponants_array(float baseUnitsExp[5],
 
     case UNIT_CONV_VOLUME:
       baseUnitsExp[UNIT_LENGTH] = 3.f;
+      break;
 
     case UNIT_CONV_INV_VOLUME:
       baseUnitsExp[UNIT_LENGTH] = -3.f;
+      break;
+
+    default:
+      error("Invalid choice of pre-defined units");
+      break;
   }
 }