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From: "David Schwartz" <davids@webmaster.com>
To: "Andrej Hosna" <hosna@ibl.sk>
Cc: <linux-kernel@vger.kernel.org>
Subject: RE: malloc(1/0) ??
Date: Tue, 7 Nov 2000 00:50:26 -0800	[thread overview]
Message-ID: <NCBBLIEPOCNJOAEKBEAKMEAPLMAA.davids@webmaster.com> (raw)
In-Reply-To: <00110709373507.05397@adino>


> > The program can't possibly work because it invokes undefined
> behavior. It
> > is impossible to determine what a program that invokes
> undefined behavior is
> > 'supposed to do'.
>
> I dont think it's undefined behaviour ...

	You are correct. This is bahavior that is undefined by the C language, but
defined by the implementation. So determining what the program was supposed
to do requires determining whether the person who wrote it was familiar with
the implementation on which it is being used. Amusingly, this means the
program is supposed to do different things depending upon what
implementation of malloc you have.

	IIRC, malloc(0) is defined to return a unique block of memory that it is
valid to pass to free. However, doing anything with this memory (read/write)
is undefined by the C standard.

	DS

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  reply	other threads:[~2000-11-07  8:50 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2000-11-07  3:59 malloc(1/0) ?? RAJESH BALAN
2000-11-07  7:54 ` David Schwartz
2000-11-07  7:59   ` Andrej Hosna
2000-11-07  8:50     ` David Schwartz [this message]
2000-11-07  8:09   ` Lyle Coder
2000-11-07  8:46     ` Matti Aarnio
2000-11-08  0:29       ` Rogier Wolff
2000-11-08  0:36         ` David Schwartz
2000-11-08  0:54     ` Igmar Palsenberg
2000-11-08  0:50   ` Igmar Palsenberg
2000-11-08 22:11     ` H. Peter Anvin
2000-11-08 22:11       ` Rasmus Andersen
2000-11-09 16:03       ` Igmar Palsenberg
2000-11-08  0:41 ` Igmar Palsenberg
2000-11-07 23:58   ` Tim Waugh
2000-11-08 12:38     ` Igmar Palsenberg
  -- strict thread matches above, loose matches on Subject: below --
2000-11-07  6:45 Dan Kegel
2000-11-07  7:13 ` J. Dow
2000-11-07  7:52   ` David Schwartz
2000-11-08  0:47   ` Igmar Palsenberg
2000-11-07  9:26 malloc (1/0) ?? David Feuer
2000-11-07 16:12 malloc(1/0) ?? Jesse Pollard
2000-11-07 16:38 ` lost

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