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From: "Giovanni Bajo" <giovannibajo@libero.it>
To: "Nick Ing-Simmons" <nick@ing-simmons.net>
Cc: <gcc@gcc.gnu.org>
References: <E7EB70E0-1AE7-11D9-A537-003065BDF310@apple.com><41698B8A.4050702@tat.physik.uni-tuebingen.de><416B47AA.3010106@codesourcery.com> <87sm8k1orb.fsf@deneb.enyo.de><416B8127.4050903@codesourcery.com> <20041013091948.4367.3@llama.elixent.com>
Subject: Re: Optimizing of explicit temporary storage
Date: Wed, 13 Oct 2004 13:02:00 -0000
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Nick Ing-Simmons wrote:

>> it would be surprising to most programmers to optimize away the call
>> because malloc *does* have side-effects on real systems.  For
>> example, on UNIX, it is likely to call sbrk, which result in
>> observable changes in the process state.
> 
> Indeed! - I have actually written
> 
> free(malloc(estimated_total_need));
> 
> To get expensive sbrk() call out of the way with one big one
> rather than many smaller ones.

So why not calling sbrk() directly?

Giovanni Bajo