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From: Sascha Hauer <s.hauer@pengutronix.de>
To: 张忠山 <zzs213@126.com>
Cc: barebox@lists.infradead.org
Subject: Re: Why sbrk clear the increased memory region
Date: Tue, 23 Apr 2019 11:49:43 +0200	[thread overview]
Message-ID: <20190423094943.iffbd35cpyi52llj@pengutronix.de> (raw)
In-Reply-To: <d2890d42-bc87-3c65-4be4-6a2c748b9ddb@126.com>

On Mon, Apr 22, 2019 at 11:13:30AM +0800, 张忠山 wrote:
> Recently, I'm using barebox in a deep embedded project, and need some funtctions
> in libc/libm, So I linked barebox with newlib
> 
> But whenever newlib call sbrk with negtive `increment`, barebox crash.
> 
> The reason is sbrk clean memory region using `increment`.
> 
> Why sbrk must clear the increased memory region?

sbrk is used only for dlmalloc in barebox. AFAIK the dlmalloc
implementation needs the memory cleared. Also dlmalloxc probably never
calls sbrk with a negative increment, so this was never an issue.

Sascha

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      reply	other threads:[~2019-04-23  9:49 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-04-22  3:13 张忠山
2019-04-23  9:49 ` Sascha Hauer [this message]

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