From: Ian Lance Taylor <iant@google.com>
To: Mohamed Shafi <shafitvm@gmail.com>
Cc: gcc-help@gcc.gnu.org, Rohit Arul Raj <rohitarulraj@gmail.com>
Subject: Re: structure packing
Date: Fri, 22 May 2009 13:51:00 -0000 [thread overview]
Message-ID: <m3hbzds22t.fsf@google.com> (raw)
In-Reply-To: <ba0bd44d0905212356j7064835dw4b215ef27d15b30d@mail.gmail.com> (Mohamed Shafi's message of "Fri\, 22 May 2009 12\:26\:00 +0530")
Mohamed Shafi <shafitvm@gmail.com> writes:
> I thought so. With STRICT_ALIGNMENT = 1 the compiler makes sure
> that all access are aligned. So irrespective of whether the structure
> is aligned or not to be safe it generates byte access. Am i right?
> If so in the given example the base address is 0 and the offset will
> be known to the compiler. If the compiler is aware of these two
> information can't it decide whether the structure is aligned or not?
I'm not sure. If the compiler knows the alignment of the specific
object, it may take that into account to override the packed attribute.
However, I would not be surprised if a specific case like casting 0 to
an address does not record the alignment even though it is known, since
that is such an odd case.
Ian
next prev parent reply other threads:[~2009-05-22 13:24 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <ba0bd44d0905210723n5e6e85f5rea8b2b52c381d5d9@mail.gmail.com>
2009-05-21 14:39 ` Mohamed Shafi
2009-05-22 6:39 ` Ian Lance Taylor
2009-05-22 8:01 ` Mohamed Shafi
2009-05-22 13:51 ` Ian Lance Taylor [this message]
2014-01-16 10:45 vijay nag
2014-01-16 11:34 ` David Brown
-- strict thread matches above, loose matches on Subject: below --
2008-10-20 7:52 Duft Markus
2008-10-20 7:33 Duft Markus
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