From:	zacharyshort AT hotmail DOT com (ZMAN)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: DJGPP reserves wrong int size
Date:	24 Jun 2001 17:42:36 -0700
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References:	<9dde68b7 DOT 0106241053 DOT 2a385311 AT posting DOT google DOT com> <200106242138 DOT RAA18013 AT envy DOT delorie DOT com>
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To:	djgpp AT delorie DOT com
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DJ Delorie <dj AT delorie DOT com> wrote in message news:<200106242138 DOT RAA18013 AT envy DOT delorie DOT com>...
> > 00000000 55                          push ebp
> > 00000001 89E5                        mov ebp,esp
> > 00000003 83EC04                      sub esp,byte +0x18
> > 00000006 C745FC78563412              mov dword [ebp-0x4],0x12345678
> > 0000000D C9                          leave
> > 0000000E C3                          ret
> > 
> > The third line reserves 18 bytes.
> > And it should reserve 4 bytes because thats the size of an int right?
> > If you declare a char it still reserves 18 bytes.
> > Could someone tell me what's going on?  I am loosing my mind!
> > Line 4 is correct though.
> 
> The purpose of that is to keep the stack aligned to a 32 byte
> boundary, which improves performance on today's high-end processors.
> 
>   4 (the call) + 4 (the push) + 24 (the sub) = 32
> 
> You can change that with command line options (-mpreferred-stack-boundary=)

Thanks you for clearing that up.
I feel like an idiot.

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