Re: Ada and Automotive Industry

[Ted Dennison <dennison@escmail.orl.lmco.com>]

Chris Hills wrote:
> 
> I could depend on the REAL (as in it had a customer and HAD TO WORK in
> a real environment)  program written in C but we could not depend on
> the same program in Mod2 because the develpoment system was bug
> ridden. In other words the Mod2 program would not perform as the
> language dictated and the program was unsafe.

I'm routinely suprised how bug-ridden REAL (commercial) C programs are.
Most products seem to be shipped with known bugs that apparently the
developers couldn't figure out how to fix. So the user is just expected
to *learn* where the bugs are and avoid those activities that seem to
cause them. What is even more startling is how users will rationalize
this away, yet jump all over Ada whenever it has even *touched* a piece
of equipment that failed.

Of course you are smarter than that, right?

> The Ariane 5 rocket had Ada Sw (a "Safe" language) and crashed after 
> 39 seconds (a bit of a red herring as Ada was not directly to blame 
> and the same could have been done in C or Mod2) SO what is the excuse 
> here? the Sw team did not understand the use of the language? If it is 
> that hard to use and that easy to miss use it is unsafe in practice.

(sigh) I guess not.

Actually, the cited reason was a decision made during
*requirements*analysis*, having nothing whatsover to do with ignorance
or knowledge of any particular language.

Of course even if the problem were what you said, it wouldn't mean much.
ALL software has bugs; C software and Ada software. The point is that if
your primary goal is low-error software, you should choose tools and
methodoligies that are the least error prone, and make it the easiest to
spot (and non-intrusively fix) errors. In this day and age, there is
little doubt as to the relative ranks of C and Ada in this regard. You
must then staff the project with people who know how to properly use the
tools, or it is all for naught. 

-- 
T.E.D.          
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