Ada Validation

[KMays@msn.com (Kenneth Mays)]

Subject: The Validation of Ada95

Greetings,

The Ada Joint Program Office (AJPO) runs the show in validating Ada95 
compilers. This issues
deal the Ada95 compiler (whether a true cross-compiler or basic 
compiler) being compliant
to the Ada95 RM. This means that the Ada95 compiler is not a subset 
or superset of the
Ada95 language - it is the standard version of the language.

Now, validation doesn't mean "bug-free". Validation only means it 
complies strictly to the rules
set forth by the AJPO's Ada Compiler Validation Capability (ACVC) 
model. For those of you who never read DoD Directive 3405.2, it 
states that only validated compilers may be used in mission critical 
systems.
Supposedly, you should see an emblem of a pentagon with the words 
"Validated Ada" within the pentagon. Now, who is to say that a vendor 
doesn't use the emblem to sell of a validated Ada83 compiler that can 
compile a subset or superset of Ada95 code?!? Since the DoD Directive 
was out in 1987, maybe we should change it to say "Validated Ada95" 
within the pentagon. Then, there is an issue of 100% compliant or  
98%. If you are going to use this spanking new Ada compiler for your 
mission critical system do you want a non-validated, bug-ridden, 
non-standard Ada something compiler in your embedded system. I think 
not.  You'd want your compiler to comply to some standard, and hope 
you didn't spend $500+ on some hack. Then again, validation doesn't 
mean bug-free - so understand that part as well. ALSO, if any 
compiler doesn't conform to the validation it must state in the 
documentation or program that it is a subset or superset of the 
language or just a hack). This protects (you hope) the user from a 
hardware dependent version (must use a certain library from a certain 
computer to work correctly (read JAVA)).

Basically, if you run code on your SGI platform with a validated 
Ada95 compiler - I can compile it ona Sun workstation with another 
Ada95 validated compiler. You shouldn't have to modify the program to 
et it to work - which makes it very portable across platforms (you 
would hope). If you use C++, you'd want to compile your nonhardware 
specific C++ programs using GCC V2.7.2 and have that same C++ program 
on AT&T C++ Release V3.x without a hickup. If you remember True 
BASIC/GWBASIC/BASICA/HP-BASIC then you might understand the 
difficulties of programming for different variants of a similar 
language.

For those of you who don't like standards (I'm not saying they are 
the answer to everything - but try SCSI on various platforms), then 
think of why ANSI/ISO, VESA, and other organizations got together. We 
can stick together an get GNAT-95 bug-ridden and Ada95 complaint for 
validation - since it is free and avalable on all systems. Then, we 
will have somewhere to start without breaking the bank.
-Ken