🚀 go-pugleaf

In article <15976@goanna.cs.rmit.oz.au> ok@goanna.cs.rmit.oz.au (Richard A. O'Keefe) writes:
> The question can now be paraphrased:  is a pointer like a tensor, or like
> the components of a tensor?  I would regard a compacting garbage collector
> as simply changing the co\"ordinate system.  I have used hardware and
> software systems where stacks could be moved (in order to "stretch" them)
> while the owning thread was running.
 
An "object" is defined (ISO 3.14) as a "region of storage". I would read
this as meaning that, for the lifetime of that object, a given object
maps to a given region of storage. Therefore, since the address of an
object is a pointer to it, the address must also be a constant. I agree
that the ice is thin and an RFI would be a good idea. You might also ask
whether &external_object_or_function has to be the same in all the
translation units of a program.

This is all, of course, modulo the "as-if" rule. Mark Brader has shown a
way to have objects move in memory whilst keeping constant addresses;
this doesn't alter what I have said.

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