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Subject: Re: in defense of GC
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From: Ray Blaak <rAYblaaK@STRIPCAPStelus.net>
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Date: Tue, 06 Feb 2007 18:01:27 GMT
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Date: 2007-02-06T18:01:27+00:00
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Markus E Leypold <development-2006-8ecbb5cc8aREMOVETHIS@ANDTHATm-e-leypold.de> writes:
> I realize this might not be the beste example, since I just made it
> up. But the idea is, that (string ref) is (by the compiler) translated
> into a char* and that result := ... actually becomes a malloc() plus a
> copying of memory. some_var := None would compile to explicit
> deallocation (pointer is overwritten with null).

I am not convinced you can avoid GC. Can the compiler insert the appropriate
deallocation calls? How would it know the string is not in use somewhere else?

So I see only that some sort of reference counting scheme can be implemented
in the restricted case, but that is just GC all over again, and a poor one at
that.

> Similarily, I think, it might be possible to avoid malloc() if
> everything is done in static or local buffers.

I don't think so. Many algorithms have unbounded and unpredictable memory
usage patterns. These could only be handled by viewing the (large?) static
buffers as preallocated memory, and then one has the equivalent of malloc
and/or GC all over again.

-- 
Cheers,                                        The Rhythm is around me,
                                               The Rhythm has control.
Ray Blaak                                      The Rhythm is inside me,
rAYblaaK@STRIPCAPStelus.net                    The Rhythm has my soul.