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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Pascal Calling Convention
Date: Wed, 30 Mar 2011 18:34:41 -0400
Organization: The World Public Access UNIX, Brookline, MA
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Date: 2011-03-30T18:34:41-04:00
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tmoran@acm.org writes:

>    What does software/hardware Data Excecution Prevention do on Vista etc?

I believe DEP causes the operating system to set per-page protections so
data is not executable, by default.  The checks are done in hardware.
And of course code pages are not writeable by default.  A process can
request other page protections.  Requires newer versions of x86.

Linux can do the same thing.

This is pretty old technology.  x86 is just recently catching up.

> (Other than generate spurious errors.)

We eliminated almost all trampolines from GNAT, so newer versions
won't cause such spurious errors.

- Bob