Path: utzoo!mnetor!uunet!lll-winken!lll-tis!ames!umd5!brl-adm!brl-smoke!gwyn
From: gwyn@brl-smoke.ARPA (Doug Gwyn )
Newsgroups: comp.sys.m6809
Subject: Re: Intrinsics (was: E)Don't use Scanf()
Message-ID: <7593@brl-smoke.ARPA>
Date: 31 Mar 88 10:36:45 GMT
Reply-To: gwyn@brl.arpa (Doug Gwyn (VLD/VMB) <gwyn>)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 16
Keywords: C stdio library

In article <2108@svax.cs.cornell.edu> belmonte@sleepy.cs.cornell.edu (Matthew Belmonte) writes:
>As I said before, nothing practical prevents one from including the
>semantics of standard functions in compilers.

An implementation note:  ANSI C (as currently proposed) permits an
implementation to provide macro definitions for "functions" in the
standard headers.  However, the library must include actual functions
so that pointers to them can be used.  A programmer needing to access
an actual function would first have to #undef the possible macro.

Thus, although the compiler is not allowed to treat sqrt() (for
example) as an intrinsic, it IS allowed to treat __sqrt() as one,
with <math.h> defining sqrt to be __sqrt.  The programmer need not
be aware that an intrinsic is being used.

Now that there (almost) is a standard for the C library, it becomes
more rewarding to implement several common functions as intrinsics.