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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 08:32:07 GMT
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Markus E Leypold <development-2006-8ecbb5cc8aREMOVETHIS@ANDTHATm-e-leypold.de> writes:
> BTW, you've been discussing (with ... I don't remember) the possibilty
> of switching GC off. My idea (even with ML-like languages) was always
> to define a subset of the language which the compiler can implement
> with a stack only. 

Does that automatically preclude any access types, unbounded strings, etc.,
then? That would be quite a limited language.

That would simplify GC right off the bat. Maybe it wouldn't be needed at all,
right there.

> One advantage of that would be that one could start out with code that
> requires GC, but is "obviously" correct and then transform in
> correctness preserving steps it into code that doesn't require
> GC. Both implementations could be tested against each other, at least
> as far as their computational function goes, not the real time
> capabilities that are perhaps only possessed by the 2nd variant.

My reaction is to not trust testing only to gain the measure of confidence
needed. You must be able to prove the the equivalence well enough.

Also, if the non-GC version was realtime, why wouldn't the first one be? Where
is the difference in behaviour? If you have no heap, then wouldn't execution
should be equivalently predictable in either case?

-- 
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.