Subject: Re: problems with arpa/inet.h
To: None <current-users@NetBSD.ORG>
From: Scott Reynolds <scottr@Plexus.COM>
List: current-users
Date: 06/09/1998 13:17:49
On Tue, 9 Jun 1998 wrote:

> In <> Alan Barrett 
> <> writes:
> >Mike Long <> said:
> >> Multiple inclusion protection does not keep cpp from reading the whole
> >> header each time it is #included.
> >
> >This is just a SMOP.  Nothing prevents the compiler from noticing when a
> >file consists entirely of comments, blank lines, and [...]
> And in fact, cccp (gnu's cpp) already does this.

The main problem with this reasoning is that cpp only knows this for a
single invocation. I don't know about you, but compiling one source file
and that may have one or two files included multiple times is simply _not_
a concern.  The real issue is having headers pull in other headers (which
may pull in other headers)... think `how much output from cpp is cc1 going
to have to chew on?'  Now, multiply this processing time by N source