There is no easy way to guarantee that the COM port object is still there when you destroy the Reader object if the destruction happens during global destruction (which it sounds like it may be in your case). The reason is that global destruction goes by force, and nobody is safe (necessary to be sure that circular references get cleaned up). I believe that 5.8 has a hack to make sure that things often get cleaned up in a convenient order, but there are cases where that fails.

Instead arrange to have the object cleaned up in an END block. END blocks are processed before global destruction, and so you can safely rely on things that you expect to still find alive, not being destroyed out of order.

In reply to Re: Destructor Order by tilly
in thread Destructor Order by sgifford

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