Date: Tue, 31 Jul 2001 16:51:22 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: Christian Merz <cmerz AT bndlg DOT de>
cc: djgpp AT delorie DOT com
Subject: Re: ds==ss why?
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On Tue, 31 Jul 2001, Christian Merz wrote:

> can I change the behavior of gcc concerning that ds==ss?

Not easily.  GCC generates 32-bit code which assumes a flat address space 
with no segmentation, so it uses 32-bit addresses to reference 
variables on the stack and in the data section.  To make this work, the 
DJGPP startup code loads DS and SS with the same selector, and assumes 
that these selectors stick.  If you break this assumption, programs will 
start crashing high and low, unless you modify the GCC code-generating 
back-end to produce instructions with 48-bit addresses that include the 
selector as well as the offset.