Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Path: utzoo!mnetor!uunet!lll-winken!ubvax!mitsumi!jimm
From: jimm@mitsumi.UUCP (Jim Mackraz)
Newsgroups: comp.lang.c,comp.sys.atari.st,comp.sys.amiga
Subject: Re: 32bit = 16bit x 16bit
Message-ID: <563@mitsumi.UUCP>
Date: Tue, 20-Oct-87 15:22:47 EDT
Article-I.D.: mitsumi.563
Posted: Tue Oct 20 15:22:47 1987
Date-Received: Fri, 23-Oct-87 06:14:00 EDT
References: <1912@gryphon.CTS.COM> <3294@sol.ARPA> <2545@cbmvax.UUCP>
Reply-To: jimm@mitsumi.UUCP (James Mackraz)
Organization: Mitsumi Technology Inc
Lines: 37
Xref: mnetor comp.lang.c:5060 comp.sys.atari.st:5820 comp.sys.amiga:9704

In article <2545@cbmvax.UUCP> andy@cbmvax.UUCP (Andy Finkel) writes:
)In article <3294@sol.ARPA> crowl@cs.rochester.edu (Lawrence Crowl) writes:
)>In article <1912@gryphon.CTS.COM> mhatter@pnet02.CTS.COM
)>(Patrick E. Hughes) writes:
)>>I might suggest one thing if you plan on porting many C programs: Don't Use
)>NO!  Char, short, and long do change size.  The only thing you can rely on is
)>that sizeof char <= sizeof short <= sizeof int <= sizeof long.  If you want
)>portable programs, DO NOT USE BASIC TYPES.  At the top of the program, define a
)
)We at the Banzai Institute always use typedefs :-)
)Ours are stored in the include file exec/types.h
)To maintain readability, however, the names were a bit a bit boring, ie
)LONG, ULONG, WORD, UWORD, BYTE, UBYTE, and VOID.
)andy finkel		{ihnp4|seismo|allegra}!cbmvax!andy 

Well, one qualification on this business is that sometimes you want
Mr. Compiler to choose its most efficient type.  For example, in Intuition,
there was a large number of cases where SHORT was used in loop counters,
and other places where a small counting number was needed.

There appeared to be explicit sign extension operation frequently applied
to these SHORTs.  When many SHORTS were converted to 'ints', the resulting 
code was significantly smaller (note: significant to people who changed
the name "rawinput" to "ri" because we needed the 6 bytes.  Yea, significant
to people who waited from Jul 31 to Aug 1 for the big build because that
second digit in the date string, multiplied by the number of libraries, ...).

It also broke where a pointer to an 'int' was passed to a program expecting
a pointer to a SHORT.

But *sometimes*, there are *some* reasons for saying 'int' instead of either
LONG or SHORT.

	jimm
-- 
	Jim Mackraz
	Mitsumi Technology, Inc.		408/980-5422
	{amiga,pyramid}!mitsumi!jimm