PP0017

Unfrozen object leaked before end of global code

If an unfrozen, non intrinsic object is used as an argument to a call of an abstract function, the function will see the object in its final state, which might be different from the state it would have had at the time of the call in code that has not been pre-packed. To make sure that this cannot be the case, call Object.freeze on the object before using it as an argument.