Date: Thu, 2 Feb 2012 17:28:30 +0100 (CET)
From: Michael Matz <matz@suse.de>
To: Aldy Hernandez <aldyh@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
        Jakub Jelinek <jakub@redhat.com>, Torvald Riegel <triegel@redhat.com>,
        Jan Kara <jack@suse.cz>, LKML <linux-kernel@vger.kernel.org>,
        linux-ia64@vger.kernel.org, dsterba@suse.cz, ptesarik@suse.cz,
        rguenther@suse.de, gcc@gcc.gnu.org
Subject: Re: Memory corruption due to word sharing
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Hi,

On Thu, 2 Feb 2012, Aldy Hernandez wrote:

> > Seriously - is there any real argument *against* just using the base 
> > type as a hint for access size?
> 
> If I'm on the hook for attempting to fix this again, I'd also like to 
> know if there are any arguments against using the base type.

Sure.  Simplest example: struct s {int i:24;} __attribute__((packed)).

You must access only three bytes, no matter what.  The basetype (int) is 
four bytes.


Ciao,
Michael.
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