From owner-freebsd-tinderbox@FreeBSD.ORG  Wed Feb 18 07:00:54 2009
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Date: Tue, 17 Feb 2009 23:58:26 -0700 (MST)
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From: "M. Warner Losh" <imp@bsdimp.com>
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Cc: mips@FreeBSD.org, tinderbox@FreeBSD.org, current@FreeBSD.org
Subject: Re: [head tinderbox] failure on mips/mips
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In message: <B23797BE-91FB-4AE1-8370-E77D66ED05B6@mac.com>
            Marcel Moolenaar <xcllnt@mac.com> writes:
: 
: On Feb 17, 2009, at 10:42 PM, M. Warner Losh wrote:
: 
: > : A safer approach is to mark ifi_epoch as packed or put differently,
: > : define time_t as a 64-bit integral with 32-bit alignment. This can
: > : avoid a lot of unexpected internal padding as well (e.g. struct
: > : timeval).
: >
: > Marking it as packed won't help.  If the elements aren't properly
: > aligned, gcc won't access multi-word entities properly.  It might
: > eliminate the warning, but it will break at runtime.
: 
: But GCC will use a pair of 32-bit loads and/or stores to
: access the 64-bit integral in that case. There should be
: no runtime breakage. You only do this for n32 of course.

Why only n32?  Registers are still 64-bit in n32.

Warner