From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <d6c1331c41a97e88c9db8a5d54d2a1d8@quanstro.net>
From: erik quanstrom <quanstro@quanstro.net>
Date: Fri, 21 Dec 2007 19:20:26 -0500
To: 9fans@cse.psu.edu
Subject: Re: [9fans] 8c padding problem
In-Reply-To: <8ea9211edc9a0cad52683bcd6ae3f64d@9netics.com>
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> but it doesn't have to be.  this is legit:
> 
> 	typedef struct{
> 		Ehdr;		// 1
> 		Ehdr;		// 2
> 		uchar	op[2];
> 	}Pkt;

my explinations stink.  perhaps this gets at what
i'm saying better.  the structure S0 won't have
any padding, yet the two calls to frobehdr are
just fine.  i'm not sure i see the alignment problem
that requires padding all unnamed structures.

	typedef struct{
		uchar	s[6];
		uchar	d[6];
		uchar	t[2]
	}Ehdr;

	frobehdr(Ehdr*)

	typedef struct{
		uchar	s0[6];
		uchar	d0[6];
		uchar	t0[2]
		uchar	s1[6];
		uchar	d1[6];
		uchar	t1[2]
	}S0;

	void
	thunk0(void)
	{
		S0 *s;
		frobehdr((Ehdr*)s->s0);
		frobehdr((Ehdr*)s->s1);
	}


- erik