Path: utzoo!utgpu!attcan!uunet!husc6!rutgers!rochester!pt.cs.cmu.edu!PLAY.MACH.CS.CMU.EDU!bsy
From: bsy@PLAY.MACH.CS.CMU.EDU (Bennet Yee)
Newsgroups: comp.arch
Subject: NULL pointers (was: Software Distribution)
Keywords: software distribution, null pointers
Message-ID: <3112@pt.cs.cmu.edu>
Date: 27 Sep 88 18:08:48 GMT
References: <978@esunix.UUCP>
Sender: netnews@pt.cs.cmu.edu
Organization: Cranberry Melon
Lines: 18

....
blithering about universal intermediate languages and cost for checking
every pointer reference to enforce *NULL == NULL
....

Of course, if your machine core dumps on dereferencing NULL, just trap the
fault (SIGSEGV), check the instruction that caused the trap, and patch up
and return if it was due to dereferencing NULL; otherwise dump core.  If we
presume that most pointers dereferenced are not NULL, then the run-time
costs are small.  It's a very machine dependent solution, but certainly can
be done on any Unix machine.

-bsy
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