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Path: utzoo!henry
From: henry@utzoo.UUCP (Henry Spencer)
Newsgroups: comp.lang.c
Subject: Re: constant expression rules
Message-ID: <8673@utzoo.UUCP>
Date: Mon, 28-Sep-87 22:01:46 EDT
Article-I.D.: utzoo.8673
Posted: Mon Sep 28 22:01:46 1987
Date-Received: Mon, 28-Sep-87 22:01:46 EDT
References: <3018@ulysses.homer.nj.att.com>
Organization: U of Toronto Zoology
Lines: 16
Keywords: portability

> The question is - what is a reasonable level of constant folding that
> I can assume when trying to write portable code? ...

Well, read X3J11's latest draft for what you *ought* to be able to assume.
Now, in reality:

	1. Keep It Simple.  Keep It Simple.  Keep It Simple.

	2. Casts were a late addition to the language and to some compilers;
		expect trouble there.

	3. Compile-time floating-point evaluation is another dangerous area,
		especially in cross-compilers.
-- 
"There's a lot more to do in space   |  Henry Spencer @ U of Toronto Zoology
than sending people to Mars." --Bova | {allegra,ihnp4,decvax,utai}!utzoo!henry