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Date: Thu, 20 Nov 2003 01:57:14 +1300
From: Andrew Hill <dru AT treshna DOT com>
Subject: problem with sizeof struct alignment
To: cygwin AT cygwin DOT com
Message-id: <3FBB68AA.6030409@treshna.com>
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 Debian/1.3-5

I have this struct


typedef struct {
double arrival;
double departure;
char status;
int bookingid;
int userid;
} RoomStatus;


I'm using gcc with no compiler options or flags.  Under linux with gcc, 
sizeof(RoomStatus) returns me 28 - as i would expect. If I use a borland 
C++ compiler it also returns a sizeof 28. But with cygwin + gcc it 
returns a sizeof 32.  I'm a bit confused. Does cgwin + gcc align to 
nearest 8bytes for structs?  Is there a compiler option to tell it to 
use 4 byte alignment?  Is it just me whos having this problem?

I checked the sizeof for int, double and char and they all correct, 
changing the char to an int or specifically saying its a 4bit int 
doens't seem to make any difference.



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