From: Marek Vasut <marek.vasut@gmail.com>
To: u-boot@lists.denx.de
Subject: [U-Boot] [PATCH] Prevent malloc with size 0
Date: Mon, 2 Apr 2012 06:23:50 +0200 [thread overview]
Message-ID: <201204020623.50669.marek.vasut@gmail.com> (raw)
In-Reply-To: <CALButCKJLDhkbiMgc1S22V-VtjMp_X5i8yv2jdyLqvAyO8V=3w@mail.gmail.com>
Dear Graeme Russ,
> Hi Marek,
>
> On Mon, Apr 2, 2012 at 1:36 PM, Marek Vasut <marek.vasut@gmail.com> wrote:
> > Dear Mike Frysinger,
> >
> >> On Sunday 01 April 2012 20:25:44 Graeme Russ wrote:
> >> > b) The code calling malloc(0) is making a perfectly legitimate
> >> > assumption
> >> >
> >> > based on how glibc handles malloc(0)
> >>
> >> not really. POSIX says malloc(0) is implementation defined (so it may
> >> return a unique address, or it may return NULL). no userspace code
> >> assuming malloc(0) will return non-NULL is correct.
> >
> > Which is your implementation-defined ;-) But I have to agree with this
> > one. So my vote is for returning NULL.
>
> Also, no userspace code assuming malloc(0) will return NULL is correct
>
> Point being, no matter which implementation is chosen, it is up to the
> caller to not assume that the choice that was made was, in fact, the
> choice that was made.
>
> I.e. the behaviour of malloc(0) should be able to be changed on a whim
> with no side-effects
>
> So I think I should change my vote to returning NULL for one reason and
> one reason only - It is faster during run-time
Well, this still might break some code which assumes otherwise ... like you
said. And like I said, let's break it because it worked only be a sheer
coincidence ;-)
> Regards,
>
> Graeme
Best regards,
Marek Vasut
next prev parent reply other threads:[~2012-04-02 4:23 UTC|newest]
Thread overview: 75+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-10-21 9:24 [U-Boot] [PATCH] Prevent malloc with size 0 Kostaras Nikolaos
2010-10-21 11:25 ` Joakim Tjernlund
2010-10-21 11:32 ` Wolfgang Denk
2010-10-21 11:45 ` Joakim Tjernlund
2010-10-21 11:51 ` Wolfgang Denk
2010-10-21 11:56 ` Joakim Tjernlund
2010-10-21 12:02 ` Wolfgang Denk
2010-10-21 12:54 ` Joakim Tjernlund
2010-10-21 19:51 ` Mike Frysinger
2010-10-21 21:10 ` Graeme Russ
2010-10-21 21:27 ` Mike Frysinger
2012-03-31 19:59 ` Marek Vasut
2012-04-01 12:25 ` Joakim Tjernlund
2012-04-01 14:01 ` Marek Vasut
2012-04-01 14:15 ` Joakim Tjernlund
2012-04-01 14:21 ` Marek Vasut
2012-04-01 22:40 ` Graeme Russ
2012-04-01 23:45 ` Marek Vasut
2012-04-01 23:52 ` Graeme Russ
2012-04-02 0:13 ` Marek Vasut
2012-04-02 0:25 ` Graeme Russ
2012-04-02 1:04 ` Marek Vasut
2012-04-02 1:40 ` Graeme Russ
2012-04-02 2:51 ` Marek Vasut
2012-04-02 3:05 ` Graeme Russ
2012-04-02 6:39 ` Joakim Tjernlund
2012-04-02 3:12 ` Mike Frysinger
2012-04-02 3:16 ` Graeme Russ
2012-04-02 3:36 ` Marek Vasut
2012-04-02 3:43 ` Graeme Russ
2012-04-02 4:23 ` Marek Vasut [this message]
2012-04-02 4:27 ` Graeme Russ
2012-04-02 6:55 ` Joakim Tjernlund
2012-04-02 7:17 ` Graeme Russ
2012-04-02 7:40 ` Joakim Tjernlund
2012-04-02 14:05 ` Marek Vasut
2012-04-02 14:26 ` Joakim Tjernlund
2012-04-02 14:42 ` Marek Vasut
2012-04-02 15:08 ` Joakim Tjernlund
2012-04-02 15:23 ` Marek Vasut
2012-04-02 16:00 ` Joakim Tjernlund
2012-04-02 16:39 ` Marek Vasut
2012-04-02 17:22 ` Joakim Tjernlund
2012-04-02 18:00 ` Marek Vasut
2012-04-02 18:40 ` Joakim Tjernlund
2012-04-02 19:14 ` Mike Frysinger
2012-04-02 21:02 ` Joakim Tjernlund
2012-04-02 19:23 ` Marek Vasut
2012-04-02 20:28 ` Graeme Russ
2012-04-02 20:56 ` Joakim Tjernlund
2012-04-02 20:59 ` Graeme Russ
2012-04-02 21:14 ` Joakim Tjernlund
2012-04-02 23:35 ` Graeme Russ
2012-04-03 10:35 ` Graeme Russ
2012-10-16 6:31 ` Marek Vasut
2012-10-16 9:22 ` Joakim Tjernlund
2012-10-16 10:43 ` Marek Vasut
2012-10-16 11:46 ` Joakim Tjernlund
2012-10-16 10:43 ` Wolfgang Denk
2012-10-16 22:41 ` Graeme Russ
2012-04-02 3:10 ` Mike Frysinger
2012-04-02 3:36 ` Marek Vasut
2010-10-22 6:10 ` Joakim Tjernlund
2010-10-22 7:18 ` Reinhard Meyer
2010-10-22 7:47 ` Joakim Tjernlund
2010-10-22 7:20 ` Mike Frysinger
2010-10-22 7:37 ` Joakim Tjernlund
2010-10-22 7:55 ` Mike Frysinger
2010-10-22 8:34 ` Joakim Tjernlund
2010-10-22 15:18 ` Mike Frysinger
2010-10-22 16:40 ` Joakim Tjernlund
2010-10-22 17:06 ` Mike Frysinger
2010-10-23 9:14 ` Joakim Tjernlund
2010-10-22 17:36 ` Scott Wood
2010-10-23 9:23 ` Joakim Tjernlund
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