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From: erik quanstrom <quanstro@quanstro.net>
To: sstallion@gmail.com, 9fans@9fans.net
Subject: Re: [9fans] ureg alignment
Date: Fri,  9 May 2014 10:31:49 -0400	[thread overview]
Message-ID: <9bca01ca1ac85fadafe2959cf3f7af87@mikro.quanstro.net> (raw)
In-Reply-To: <CAGGHmKF-upNXMZjzhrmp4zGsFvS25hx2BJeZapndYB0QbusgJw@mail.gmail.com>

> Ugh, no! Is there a case where the padding is a problem? Normally
> registers belonging to the same union are uniform in size. Those
> defines will expand anywhere and not behave as expected:
>
> ulong sp = ureg->sp;
>
> This could lead to all sorts of entertaining problems.

any union on a 64-bit machine will get padded out to 0%8 bytes.

also your example

	ulong sp = ureg->sp

will get expanded to

	ulong r13 = ureg->r13

and this is just fine!

- erik



  reply	other threads:[~2014-05-09 14:31 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-05-09 14:21 erik quanstrom
2014-05-09 14:28 ` Steven Stallion
2014-05-09 14:31   ` erik quanstrom [this message]
2014-05-09 14:56 ` Charles Forsyth
2014-05-09 15:29   ` erik quanstrom
2014-05-09 15:45     ` Charles Forsyth
2014-05-09 15:52       ` erik quanstrom

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