Re: Garbage Collection in Ada

[dewar@merv.cs.nyu.edu (Robert Dewar)]

Lars said

"I'm genuinely puzzled and simply trying to figure out which of the
conflicting views is right: (1) my limited experience combined with
others claims that the set of falsely retained pointers is relatively
small. A small, perhaps negligible problem. or (2) Your claims that this
is a serious error that likely will make my program fail. The views
simply don't match. I need more information."

That is a complete misreading of what I said, please go to an archive and
reread the thread! I never said that it would "likely" make your program
fail. I simply said that

(a) there was a non-zero probability that a program relying on CGC could fail
(b) at least for my application areas, I am not interested in programs that
    may fail unpredictably, even if the probability is small.

Sure there are many things that may make a program fail, but these are bugs
that must be stamped out. I don't see that it is reasonable to build into
a program a technique that by its very nature introduces this kind of
unreliability.

Your experience says nothing to answer this concern. If you cut corners on
maintaining your personal airplane, and manage to fly around without crashing,
that does not constitute evidence that the recommended careful mainteance
is a bad idea.

There is a big difference between "my program seems to work", and "I have
designed my program to be reliable to the best of my ability".

Note again the important exception that if the only issue is performance,
then it seems quite reasonable to rely on CGC to generally improve 
performance in the average case.
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