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From: barmar@think.COM (Barry Margolin)
Newsgroups: comp.lang.c
Subject: Re: effect of free()
Message-ID: <29558@news.Think.COM>
Date: 15 Sep 89 19:48:34 GMT
References: <319@cubmol.BIO.COLUMBIA.EDU> <3756@buengc.BU.EDU> <1989Aug17.005548.745@twwells.com> <16022@vail.ICO.ISC.COM> <248@seti.inria.fr> <gZ3LTWu00Xc8M0Nm0l@andrew.cmu.edu> <11053@smoke.BRL.MIL> <YZ3p34a00XcA04hUZt@andrew.cmu.edu>
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Reply-To: barmar@kulla.UUCP (Barry Margolin)
Organization: Thinking Machines Corporation, Cambridge MA, USA
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In article <YZ3p34a00XcA04hUZt@andrew.cmu.edu> jdr+@andrew.cmu.edu (Jeff Rosenfeld) writes:
>any architecture capable of supporting an implementation of C must be able
>to perform a test on an arbitrary pointer. The test operation might be
>implemented through GP registers or with memory operands or whatever.
>But it HAS to be doable if the architecture can support C. 

Yes, it may be possible to compare pointers using data registers.
However, that may not be the best way to compare pointers on a
particular machine, so the compiler implementor should be permitted to
use the more optimal address registers when doing pointer operations.

Barry Margolin
Thinking Machines Corp.

barmar@think.com
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