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From: cadsi@ccad.uiowa.edu (CADSI)
Newsgroups: comp.lang.c++
Subject: Re: 64 bit architectures and C/C++
Message-ID: <1991May3.143944.1220@ccad.uiowa.edu>
Date: 3 May 91 14:39:44 GMT
References: <471@heurikon.heurikon.com>
Organization: CAD-Research, U. of Iowa, Iowa City, Iowa
Lines: 32

From article <471@heurikon.heurikon.com>, by daves@ex.heurikon.com (Dave Scidmore):
> warren@cbnewsh.att.com (warren.a.montgomery) writes:
>>There are probably a lot of hidden assumptions in programs that
>>sizeof(short)==2 and sizeof(long)==4 at this point, so any
>>assignment of meanings on a 64 bit machine (unless you invent type
>>"long long" for 64 bits and leave long and short at 32 and 16)
>>will cause some pain.
>>
>>All this raises questions about C/C++'s philosophy of integer type
>>specification, which no doubt dates from the days where all
>>machines had only 2 and 4 byte integers.
> 
> I doubt such a day ever existed. The early K&R book refered to machines
> with 9 bit chars and 36 bit integers when describing the number of bits
> in various quantities.
> 
>>...  How are things like this best
>>expressed in C or C++?
>>Do other languages provide better overall solutions?

I add another fly to the ointment.  What about bit sliced machines.
At the low level, they really are 2 and 4 bit processors.  At the
high level (most human interaction levels) they are more like
32 and/or 64 bit machines.  So, is this always a seperate issue from
the compiler?  I'm a little ignorant about the middle level of these
machines, this is why I ask.

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|Tom Hite					|  The views expressed by me |
|Manager, Product development			|  are mine, not necessarily |
|CADSI (Computer Aided Design Software Inc.	|  the views of CADSI.       |
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