Re: Bounds checks. (was variable-length struct hack)

Article View: comp.std.c

Article #6113

#6113

From: Richard H. Gumpertz
Date: Wed, 13 Dec 1989 15:28

18 lines
1582 bytes

In article <1989Dec12.190347.13521@twwells.com> bill@twwells.com (T. William Wells) writes:
>The two are exactly the same:
>
>	&A[N] = &(*(A + N)) = A + N

No, the two are not exactly alike.  According to 3.3.6, *(A+N) is
undefined ("...the behavior is undefined if the result is used as an
operand of a unary * operator") and so &(*(A+N)) is undefined.  A+N, on
the other hand, is well defined.  I really believe that the wording in
3.3.6 is wrong; I cannot believe that the committee intended for A+N to
be legal but not &A[N].

Anyone on the committee care to respond?
-- 
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| Computer Problem Solving, 8905 Mohawk Lane, Leawood, Kansas 66206-1749      |
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<448@longway.TIC.COM> <450@longway.TIC.COM> <15364@haddock.ima.isc.com> <809@prles2.UUCP> <1989Dec8.161820.24804@jarvis.csri.toronto.edu> <1989Dec11.181631.3864@jarvis.csri.toronto.edu> <1989Dec12.190347.13521@twwells.com>

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Path: arc1-ca.pugleaf.net!utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!uunet!amgraf!cpsolv!rhg
From: rhg@cpsolv.UUCP (Richard H. Gumpertz)
Newsgroups: comp.std.c
Subject: Re: Bounds checks.  (was variable-length struct hack)
Message-ID: <466@cpsolv.UUCP>
Date: 13 Dec 89 15:28:22 GMT
References: <448@longway.TIC.COM> <450@longway.TIC.COM> <15364@haddock.ima.isc.com> <809@prles2.UUCP> <1989Dec8.161820.24804@jarvis.csri.toronto.edu> <1989Dec11.181631.3864@jarvis.csri.toronto.edu> <1989Dec12.190347.13521@twwells.com>
Reply-To: rhg@cpsolv.uucp (Richard H. Gumpertz)
Organization: Computer Problem Solving, Leawood, Kansas
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