Re: [Fwd: F22 completes 11% of its Flight tests]

[Keith Thompson <kst@cts.com>]

I should really just give up on this thread; it's showing no signs of
going anywhere.

"jtarver" <jtarver@tminet.com> writes:
> Keith Thompson <kst@cts.com> wrote in message
> news:yecaem64cny.fsf@king.cts.com...
> > "jtarver" <jtarver@tminet.com> writes:
> > > Nothing like having the rules change to deliver that Boston pork.
> > > DEC had extensions when their computer became the defacto standard
> > > for Ada.  At the time any extensions to Ada were forbidden.  Data
> > > General was rightiously upset when this was done.  I was working
> > > SDI in the 80s when Ada became the perfered controls language.
> >
> > Please be specific.  What extensions are you referring to?  (BTW, I
> > was working on Ada compilers in the 80s.)
> 
> I am refering to VAX Ada compilers with extended instruction sets.  Do you
> have a reading comprehension problem?

Not usually, but some writers do give me some trouble.  Let's try again.

I don't know what you mean by "extended instruction sets" in this
context.  The phrase "instruction set" usually refers to the set of
instructions that can be executed by a specific kind of CPU.  In this
sense, an extended instruction set would be relevant to users of an
Ada compiler only if they're using machine code insertions.  MCIs
aren't generally considered to be a language extension, though I
suppose you could look at them that way.  They're a facility for
writing deliberately non-portable code, and in my experience they're
rarely used.  (My experience may be atypical; the Ada code I wrote had
to run on multiple platforms, so of course it couldn't use MCIs.)

If you're referring to the instruction set the compiler uses for
generated code, of course that's going to be non-portable, but that
has nothing to do with extensions to Ada.

If you're referring to something else, you're not using the term
"instruction set" in the same sense most of us do.

You refer to extensions to Ada implemented in VAX Ada compilers.
Again, what extensions are you talking about?  A snippet of sample
code that depends on such an extension would be helpful.

(Note that implementation-defined pragmas and attributes have always
been specifically allowed by the language standard, and
implementation-defined library units are not extensions to the
language.)

-- 
Keith Thompson (The_Other_Keith) kst@cts.com  <http://www.ghoti.net/~kst>
San Diego Supercomputer Center           <*>  <http://www.sdsc.edu/~kst>
Welcome to the last year of the 20th century.