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Date: Fri, 4 Jan 2008 14:15:29 +0100
From: Marco van de Voort <marcov@stack.nl>
To: Ivan Voras <ivoras@freebsd.org>
Message-ID: <20080104131529.GA31354@stack.nl>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Architectures with strict alignment?
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On Sat, Dec 08, 2007 at 03:43:30AM +0100, Ivan Voras wrote:

> Which of the architectures FreeBSD supports (if any) have strict memory
> alignment requirements? (in the sense that accessing a 32-bit integer
> not aligned on a 32-bit address results in a hardware trap/exception).

I do know that older PPCs (PowerPC603) have a requirement on aligning of
floats.

IIRC the e.g. Linux the kernel hooks an exception handler that makes it
transparent for apps (at the cost of some performance), and NetBSD does not
I never ran FreeBSD on PPC, so I wouldn't know that one.