[fpc-pascal] re-newing a pointer

[spir ☣]

Hello,

It seems that once a pointer has been assigned nil, it needs to be (re)allocated using new() before using it to (re)set its target:

...
p := nil;	// pointer to Integer
...
new(p) ; p^ := 1;

Is this hypothesis correct?

Use case: Linked List
nil is used in the "toNext" field of a list's last node, as a kind of end mark. When a new node is appended, I need to "renew" the toNext pointer to let the now forelast node hold a reference to the new one:

	// l is the list, n the new node
	// currently, l.toLast^.toNext = nil
	p := l.toLast;
	new(p^.toNext) ; p^.toNext^ := n;
	l.toLast^ := n;


Denis
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vit esse estrany ☣

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