From:	Matthew Mastracci <mmastrac AT acs DOT ucalgary DOT ca>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Djgpp and Asm
Date:	Sun, 6 Jul 1997 22:50:11 -0600
Organization:	The University of Calgary
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Message-ID:	<5ppsjt$gfs@ds2.acs.ucalgary.ca>
References:	<33BFE434 DOT 392 AT nowhere DOT com>
Reply-To:	Matthew Mastracci <mmastrac AT acs DOT ucalgary DOT ca>
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To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

On Sun, 6 Jul 1997, john Conner wrote:

> asm("leal _RAM,%ebp");    /* RAM is a c pointer */
> 
> It crashes every time. I get a gpf or stack fault. 
> It works fine if I use esi,edi,ect. Any help?

Forgive me if I'm wrong, but isn't the proper line:

asm("leal %ebp,_RAM");

Your line is moving the contents of _RAM (undefined at the time, I'm
assuming)  to ebp.  AT&T syntax is "backwards" (in relation to Intel). 
The opcodes act like:

grammer: [verb] FROM [src] TO [dest]   
opcode: [verb] [src], [dest]
ie: movb 5, %eax

instead of:

grammer: [verb] TO [dest] FROM [src]   
opcode: [verb] [dest], [src]
ie: mov ax, 3

AT&T syntax makes a little more sense gramatically (in terms of English),
but for people raised on Intel, it's dang confusing sometimes.  ;) 

/\/\att /\/\astracci                  mmastrac AT acs DOT ucalgary DOT ca

GCS/GE    d- s+:+ a--- C++++ UA P+ L E-- W+ N++ o K+ w+ O M- V 
          PS++ PE++ Y+ PGP t+++ 5+++ X++ R++ tv+ b+++ DI++++ I 
          G++ e h r* z?

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