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Date: Wed, 14 Sep 2011 09:33:44 -0700
From: David Rothenberger <daveroth AT acm DOT org>
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Subject: Re: plotting from octave: address space already occupied, fork aborts
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On 9/14/2011 5:22 AM, Ryan Johnson wrote:
> There is some evidence [1] that flagging cygwin .exe as large address
> aware and rebasing all libraries (excepting cygwin1.dll?) into high
> addresses makes it immune to ASLR problems (the latter apparently only
> mucks with low addresses), but I don't know if anybody has ever tested
> it on octave. Emacs broke in nasty ways when marked large address-aware
> [2], though the problem has since been fixed [3].
> 
> [1] http://cygwin.com/ml/cygwin-developers/2011-06/msg00002.html
> [2] http://cygwin.com/ml/cygwin/2011-08/msg00153.html
> [3] http://cygwin.com/ml/cygwin/2011-08/msg00312.html

While it was true that DLLs could be rebased above 0x80000000, this is
no longer true [1]. The Cygwin DLL uses the high addresses for the heap
now. Still, marking all .exe files as large-address aware does help,
since it allows the heap to go into high addresses, leaving more room
for the DLLs.

[1] http://cygwin.com/ml/cygwin/2011-08/msg00066.html

-- 
David Rothenberger  ----  daveroth AT acm DOT org

Creditor, n.:
        A man who has a better memory than a debtor.

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