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I was thinking the opposite. Since RPG compiler usually do this type of things (you know auto initial alpha and numeric file, auto open file....) for RPG programmer, I kind of except the compiler to know to generate code to dealloc the memory automatically when the program set the based pointer to *null. Wishful think ... :)
Unfortunately, there's no way a compiler could do something like that. It'd have to be maintained by the operating system, which would have to monitor every use of every pointer.
For example, if you wanted the compiler to take care of it, then what about this?
midrange.com
pointer1 = %alloc(1234);
pointer2 = pointer1;
pointer1 = *null;
Should that deallocate the memory when pointer1 is set to null? If so,
what happens to pointer2? How could the compiler know that you're done
with the memory?
It's tempting to think that the compiler should know that you set the value to pointer2, and it should deallocate it and set pointer2 to null as well. But that wouldn't work in all cases. Consider this example:
pointer1 = %alloc(1234);
pointer2 = my_subprocedure(pointer1);
pointer1 = *null;
Now should the compiler know whether you're done with the memory and
auto-deallocate it? What if my_subprocedure() isn't written in RPG, but
is written in a completely different language that the compiler doesn't
understand. How can it know whether the code in my_subprocdure() is still
using the pointer? Plus, pointer2 may or may not be refering to the same
memory...
If you want a method of clearing all leftover allocations, one exists... activation groups.
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