From:	Mark Slagell <bald_soprano AT geocities DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: What registers do I have to save when using external assembler functions?
Date:	Mon, 09 Jun 1997 16:38:38 -0500
Organization:	dept. of redundancy dept.
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Message-ID:	<339C77DE.2E1@geocities.com>
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To:	djgpp AT delorie DOT com
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I can't remember the answer, but you can find out by writing a simple C
function that requests too many register variables, say six.  Compile it
(unoptimized) with the -S switch, then see which registers get saved in
the resulting assembly code.

William McGugan wrote:
> 
> What registers do I have to save when using external assembler
> functions? I'm asking because my assembly functions crash with -O, and
> I thought it might be due to DJGPP using a register variable that was
> corrupted my asm functions.
> 
> I have declared all my global variables and external functions as
> volatile, but that doesn't seem to help.
> 
> Thanks.
> 
> William McGugan
> http://www.netcomuk.co.uk/~wmcgugan

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