Re: Bye-bye Ada ? (Ada95 Wholesale Changes?)

[Ole-Hjalmar Kristensen <oleh@vlinux.voxelvision.no>]

"Warren W. Gay VE3WWG" <ve3wwg@cogeco.ca> writes:

> Hyman Rosen wrote:
> > Richard Riehle wrote:
> >
> >> In Ada, used well
> > I suspect that you are a Japanese Joiner as well :-)
> > I think that any of the regular posters here would be
> > able to program as well in C++ as in Ada. I'm pretty
> > sure that if I had to work in Ada it wouldn't take me
> > very long to get up to expert level.
> 
> Well, I can say that for small projects, your statement
> is probably true.
> 
> But I can speak for my own experience, that in
> largish C++ projects, I always spent an incredible amount of
> time looking in core files and working with a debugger to
> find out why some "strange behaviour" was happening in
> those C++ projects. Sometimes it was related to those
> automatic type promotions, and at other times, it was
> related to memory corruption problems of one sort or
> another (and it need not even be your own code! Sometimes
> C++ library code does this to you).
> 
> On top of all this, once you get your large C++ application
> to actually work, you then want to "port it" to another
> platform, with sometimes a different compiler (or even
> a different/updated gcc compiler). What do you find?
> 
>    - Changed behavior in automatic type promotion, leading
>      to changed application behavior
>    - #include file problems
>    - C++ library incompatibilities/limitations
> 
> Sure you can say that this occurs due to poor planning,
> or design. But the Ada point is that this is not checked,
> nor enforced up front by your tools.  My hobby time is
> time I hate wasting this way ;-)

I mostly agree with you, but Ada systems may bite you too. I have a
small program which essentially does a test of the speed of the file
system, while running multiple tasks. This program has been unchanged
for years, has run fine on Solaris, NT, Linux. I recently installed
SuSe 8.1, compiled the program and ran it. Result: Segmentation violation, no
other messages. Started gdb, which promptly crashed with an internal
error.  

Turned on stack checking, still same result.  

Decreased the size of the buffer, allocated on the stack, as I
suspected that I had exceeded max stack size for a task, and it
worked fine.

As a last test, increased the buffer size to twice of what it was
originally, and then got the expected exception.

-- 
Ole-Hj. Kristensen

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