Re: What happens to DEC Ada?

[dewar@gnat.com (Robert Dewar)]

gab@rational.com (Greg Bek) wrote in message news:<afb6d339.0108081124.4071a24d@posting.google.com>...

> I'm suprised to find GNAT faster than Apex for a really
> large set of source files.  My own experience is that for
> a large program Apex is usually 20% - 50% faster to
> compile a system from scratch.  Now the definition of "large"
> for me is at least 20KSLOC.  Apex is not a very fast compiler
> of hello_world.

Well Greg no doubt knows how to use the Rational compiler to best
advantage :-) and not surprisingly our skill is in the opposite
direction. But we have many customers who have found GNAT to be
faster than APEX when things are done in the most efficient
manner. This is especially true on a large multi-processor. Even
on a single processor, if there are sufficient resources, then
it is often worth using a -j switch to run multiple compilation
processes at the time.

To get a feeling for the speed of GNAT, the GNAT sources, about
300,000 lines compile in under 3 mins on my note book (which is
only 850MHz with a fairly slow disk). In practice that's fast
enough for most purposes. Of course mileage can vary, and a very
large system with very extensive inlining compiled with -gnatN
can take a lot of resources.