Re: compiler benchmark comparisons (was: naval systems)

[dewar@gnat.com (Robert Dewar)]

Kilgallen@SpamCop.net (Larry Kilgallen) wrote in message news:<TgAW8WWqYgP5@eisner.encompasserve.org>...

> When the tool that generates the makefiles is the 
> previous run of the C compiler itself, the difference
> from Ada seems quite small.

Well it is in practice quite large in most environments. 
Very few C environments update the makefile on every
compilation (using tools like make depend), and one of
the most important differences is that it is perfectly
possible to link an inconsistent C program if your
hand crafted procedures to prevent this go astray.

So in practice, most Ada programmers find this a significant advantage
of Ada over C, but of course
your mileage may vary (after all there is nothing
that requires an Ada environment to have decent tools,
although there is still something that requires it to
check for inconsistencies, unlike the case with Ada).

Actually in most Ada compilers, it is hard to make the
automatic recompilation 100% accurate anyway, e.g. many
Ada systems end up with the amount of inlining depending
on the order of compilation. So there is no magical
guarantee here (one of the advantages of the source based
approach to compilation is that in fact it is feasible to
give a 100% guarantee on dependencies and recompilation,
since you can compile clients before you compile the packages they
need, so you do know what's needed before
compiling it.