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From: jimad@microsoft.com (Jim Adcock)
Subject: Re: Zero-length structures and pointer comparisons
Message-ID: <1992Oct20.205512.8261@microsoft.com>
Date: 20 Oct 92 20:55:12 GMT
Organization: Microsoft Corporation
References: <23915@alice.att.com> <1992Oct19.055511.18826@jyu.fi> <1992Oct19.152004.8350@lth.se>
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In article <1992Oct19.152004.8350@lth.se> dag@control.lth.se (Dag Bruck) writes:
|The ordering of pointers may be implementation defined, and I don't
|even think it would have to be equal between runs of the same program.

Under many if not most OS's the ordering of pointers resulting from heap
allocations would be implementation defined, and needn't be equal between
runs of the same program.  One can usually figure out some system dependent
hack to force an ordering on allocations, but program and/or system performance
will frequently suffer.  Thus I would suggest that strong ordering constraints
should remain implementation dependent, as in the C standard.  IE speed
should never be sacrificed up front in order to address secondary concerns.