Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!uakari.primate.wisc.edu!aplcen!haven!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.lang.c
Subject: Re: sizeof a struc field
Message-ID: <11316@smoke.BRL.MIL>
Date: 17 Oct 89 04:44:35 GMT
References: <7710@microsoft.UUCP> <11086@smoke.BRL.MIL> <131@dtoa3.dt.navy.mil> <11227@smoke.BRL.MIL> <7678@cdis-1.uucp> <11263@smoke.BRL.MIL> <10960@riks.csl.sony.co.jp> <11280@smoke.BRL.MIL> <277@dsi.COM>
Reply-To: gwyn@brl.arpa (Doug Gwyn)
Organization: Ballistic Research Lab (BRL), APG, MD.
Lines: 12

In article <277@dsi.COM> dave@dsi.UUCP (Dave Rifkind) writes:
>Doug Gwyn (I think) says that dereferencing a null pointer is
>"syntactically meaningless".  Nuts!  "Null pointer" is not a syntactic
>concept--it's meaningful only at runtime.  Any pointer is potentially a
>null pointer; you can't determine "nullness" syntactically.  To suggest
>that a compiler should police runtime errors at compile time is silly.

I said that dereferencing a null pointer CONSTANT was meaningless,
and it is EXACTLY the kind of thing I want compilers to check for
me at compile time.  There is no service being rendered by a compiler,
when it is in a position to detect a usage error at compile time,
silently proceeding to generate code that may blow up at run time.