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Subject:  Re: Why NULL is 0

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From:         "Louis A. Mamakos" <louie at trantor.umd.EDU>
Subject:      Re: Why NULL is 0
Comments: To: info-c at brl-smoke.arpa
To:           Vic Kapella <SXJVK at ALASKA>

In article <124 at polygen.UUCP> pablo at polygen.uucp (Pablo Halpern) writes:
>However, if I were writing a C compiler, I would choose a size for all
>pointers equal to the size of the largest possible pointer.

Please don't do this.  On, for example, our Unisys 1100 machine, a "regular"
pointer is 8 bytes long (2 words, 72 bits).  A pointer to a function is
64 bytes long (8 words, 288 bits).  Yes, this is a word-addressable machine
with 4 9-bit bytes per word. The existing semantics work just fine if
you don't assume programmer brain-damage.

Louis A. Mamakos  WA3YMH    Internet: louie at TRANTOR.UMD.EDU
University of Maryland, Computer Science Center - Systems Programming