Re: Better support for garbage collection

[Robert A Duff <bobduff@world.std.com>]

Brian Rogoff <bpr@shell5.ba.best.com> writes:

> The cynic may counter that one doesn't see a lot of demand for Ada either. 
> Of course that says nothing about GC. 

If my company had money to burn, I would implement GC, and see if it
attracts more people to Ada.  But I wouldn't bet my own money on that.  ;-)

> I think there will never be a single approach which will work well for all 
> cases.

I strongly agree.

In fact, I think part of the reason GC didn't catch on for many years
(Java is really the first popular GC'ed language) is the overblown
claims of some GC zealots.

>... Even amongst "GC-ed" language advocates, you can see that there is
> some realization that for embedded or hard real-time problems you may need 
> other approaches. I'm thinking of the ML-Kit and it's region based memory 
> manager, http://www.it-c.dk/research/mlkit/kit3/readme.html

I've read various papers that claim to describe "real time" garbage
collection, only to be disappointed to find that its not so "hard" real
time after all (and have intolerable overheads for some programs).

> Still, I program in a GCed language now and I have to admit that my 
> "programming velocity" is better than it was with Ada (yeah, I know, who 
> cares, readability, blah, blah, blah :) and even if GC isn't the main
> reason it certainly helps. 

Which language?

> > Memory leaks are indeed annoying.  GC can help a lot.  But it doesn't
> > completely cure the problem -- you still have to use your brain when
> > writing programs.  I've seen memory leaks in GC'ed programs.
> 
> Static typing doesn't cure bugs either. 

Right, but there are fewer zealots making *that* claim.

> My worry about GC in Ada would be that the bugs caused by the interaction 
> of GC and unsafe features would be difficult.

I think I've heard Robert Dewar express that attitude (ie, perhaps GC is
inappropriate in a language that also has unsafe features).

>... I guess if you use unsafe 
> features all bets are off in any case...

That's *my* attitude.

- Bob