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- Newsgroups: comp.lang.misc
- Path: sparky!uunet!munnari.oz.au!metro!usage!syacus!ian
- From: ian@syacus.acus.oz.au (Ian Joyner)
- Subject: Re: Pointers
- Message-ID: <1992Nov23.115230.10459@syacus.acus.oz.au>
- Organization: ACUS Australian Centre for Unisys Software, Sydney
- References: <1992Nov7.115620.29967@syacus.acus.oz.au> <TMB.92Nov19002135@arolla.idiap.ch> <nevin-191192004649@90.20.3.209>
- Date: Mon, 23 Nov 1992 11:52:30 GMT
- Lines: 52
-
- nevin@apple.com (Nevin ":-]" Liber) writes:
-
- >In article <TMB.92Nov19002135@arolla.idiap.ch>, tmb@arolla.idiap.ch (Thomas
- >M. Breuel) wrote:
-
- >> C's
- >> lack (in fact, intolerance) of runtime typing and array bounds
- >> checking, on the other hand, mean that hardware designers these days
- >> seem to make little effort to support such features,
-
- >I don't see anything wrong with getting rid of features that people aren't
- >using. If those features were popular, C probably wouldn't be as popular
- >as it is today. We have lots of CISC archetectures with cool features that
- >very few people ever find useful. Why waste the silicon?
-
- Firstly, I agree that we should have very regular instruction set computers
- (RISC). However, building bounds checking into silicon while being
- something that is not essential is highly desirable. I make this comment
- against the background that silicon (gallium arsenide) if you like is
- getting cheaper and more powerful, whereas software development is getting
- more complex, and very expensive.
-
- Unfortunately these days, not many people have had experience developing
- software for machines that have such inbuilt semantics checks. However, I
- can assure you that it makes tracking down errors much easier, as the
- program is terminated straight away, with a specific error in a specific
- line of the program. Thus most bugs are found during development before
- software is shipped to customers. So better quality software is produced.
-
- That is why you would waste silicon. To get a bit philosophical, why do
- we have computers anyway? The answer is because people are important.
- They are more important than computers. So it is better to waste a computers
- time than a persons time. The whole argument of processor efficiency comes
- from the misguided philosophy that computers are more important than people.
- It is true that in the past they were very expensive. But now they are cheap,
- so why do we persist with this old assumption.
-
- Having hardware that does not have bounds checking is rather like having
- a car that has no brakes.
-
- >It's simply a feedback loop. I much prefer it to having hardware and
- >software people totally oblivious to each other.
-
- Close. I would not say "totally oblivious", but "mutually independent". This
- does not happen by accident though, but by careful design. Unfortunately,
- this C/hardware combination is making hardware and software "mutually
- dependent", and we will pay the price for this mistake in the long term.
- --
- Ian Joyner ACUS (Australian Centre for Unisys Software) ian@syacus.acus.oz
- "Where is the man with all the great directions?...You can't imagine it,
- how hard it is to grow, Can you imagine the order of the universe?" ABWH
- Disclaimer:Opinions and comments are personal.
-