Date: Thu, 24 Apr 2003 16:57:01 -0500
From: Eric Rudd <rudd AT cyberoptics DOT com>
Organization: CyberOptics
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Subject: Re: Bug 00314 -- div() still broken
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To: djgpp AT delorie DOT com
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Ben Peddell wrote:

> Eric Rudd wrote:
>
>> I think I had some problem with -fomit-frame-pointer, but I'm still 
>> investigating.
>
> Things are being pushed wrong.
> edi is supposed to hold the address of the div_t structure, yet is has 
> 0x28 (40) in it. eax and ebx are supposed to have 40 in them, yet they 
> have -3 in them.
> div() wants the stack to look like:
>     16(%ebp): divisor
>     12(%ebp): numerator
>      8(%ebp): &return
> But it appears to look like:
>     16(%ebp): something between -2 and +2
>     12(%ebp): divisor
>      8(%ebp): numerator
>
> There in lies the problem.

This confirms my suspicion that there is a problem with 
-fomit-frame-pointer.  I thought that routines in libc.a could be called 
from a program compiled either with or without -fomit-frame-pointer, but 
I found that I could call the existing div.o in libc.a only if I didn't 
use -fomit-frame-pointer.  Hmm...

-Eric Rudd
rudd AT cyberoptics DOT com