Re: GNAT & Windows NT

[dewar@cs.nyu.edu (Robert Dewar)]

"They rename the distribution to correctly identify the platform"

As you know, there are a zillion different PC platforms. All are user
level compatible (assuming we are talking 386 or above). Unless you
do something VERY weird (we have not), code running on the Pentium will
run on the 386 and 486 and vice versa (actually there are more differences
between the 386 and 486 at this level than between the 486 and Pentium).

Generally you want to distribute code that is optimized for the Pentium, 
since this can produce substantial advantages in execution efficiency. 
As Richard Kenner has noted, GCC does not yet do much in the way of
Pentium specific optimizations yet, but this may well change in the
future. Pentium optimized code runs fine on a 486, i.e. there is no
noticable penalty for such optimizations, which is why you always prefer
to ship Pentium optimized code.

The correct identification of the platform for our PC related releases
is indeed 586, since these releases were built on a Pentium. Renaming
them would be incorrect and misleading. Supplying additional ports that
are built on the 486 would be extra work and pointless, since the code
would not run faster on a 486.

Understanding this will be important to the entire PC world as we begin
to see Pentium-optimized code appear for general PC applications, and I
am sure the same confusion will arise. We will add notes to our readme
files to make sure that people (at least those who read the file!) do
not get confused on this point.

There are two ports of GNAT to NT, one built and distributed by NYU, which
is available from the NYU FTP area, and one from Labtek. The Labtek folks
specialize in NT support for GNAT, and are building some interesting NT
specific tools, so if you are interested in using GNAT on NT, you should
definitely contact them.