null pointers of various types.

Article View: comp.std.c

Article #5824

#5824

From: David Keppel
Date: Sun, 26 Mar 1989 22:01

15 lines
1040 bytes

This is a request for information.

I recently made the following assertions about pANSI C.
Are they correct?

* The number zero (0) compares equal with any null pointer of any type.
* The bit storage of a null pointer is not necessarily all zeros.
* Null pointers of two types do not necessarily compare equal.
* A null pointer of one type, cast in to another pointer type, will
  always be cast to a null pointer in the destination type.

	;-D on  ( All this, for a bunch of zeros! )  Pardo
-- 
		    pardo@cs.washington.edu
    {rutgers,cornell,ucsd,ubc-cs,tektronix}!uw-beaver!june!pardo

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Path: arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!bloom-beacon!husc6!rice!uw-beaver!uw-june!pardo
From: pardo@june.cs.washington.edu (David Keppel)
Newsgroups: comp.std.c
Subject: null pointers of various types.
Message-ID: <7672@june.cs.washington.edu>
Date: 26 Mar 89 22:01:33 GMT
Reply-To: pardo@cs.washington.edu (David Keppel)
Organization: U of Washington, Computer Science, Seattle
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