Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!microsoft!jimad
From: jimad@microsoft.UUCP (Jim ADCOCK)
Newsgroups: comp.lang.c++
Subject: Re: Comparison functions for qsort() and bsearch()
Keywords: Sun, C++
Message-ID: <60328@microsoft.UUCP>
Date: 7 Jan 91 22:56:41 GMT
References: <3069@lupine.NCD.COM> <277640DD.4A70@tct.uucp> <1990Dec26.160636.15566@clear.com> <1991Jan2.191630.18581@Think.COM>
Reply-To: jimad@microsoft.UUCP (Jim ADCOCK)
Organization: Microsoft Corp., Redmond WA
Lines: 36

ARM  pg 36 states that a pointer to any non-const, non-volatile object type
can be converted to a void*

ARM pg 69 states that a void* is considered a pointer to object type.

ARM pg 69 states that a B* can be converted to a D* if an unambiguous 
conversion exists and B is not a virtual base.

ARM pg 67 states that any conversion not mentioned on pgs 67 to 71 is
an error.

ARM pg 68 states that if you haven't yet defined a class, you can use
it in a pointer cast, in which case "no assumptions are made about class
lattices."  I leave it to the reader how a compiler performs such a cast 
without making any assumptions -- perhaps a random number is to be generated 
for the results of such a cast?

ARM pgs 67-71 do not otherwise cover possible explicit conversions from
a void* to a pointer to an object of some class.  Therefor, I claim
either:

1) Casts from a void* to a pointer to an object of some class already 
defined are in error.

or

2) The definitions given by ARM pgs 67-71 are in error.

and either:

3) No assumptions may be made about casts from a void* to a pointer to an
object of a class not yet defined.

or

4) The definitions given by ARM in these regards are in error.