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Re: gcc 3.2.3 config/os/bits/i386/atomicity.h broken
- From: Andreas Jaeger <aj at suse dot de>
- To: Loren James Rittle <rittle at latour dot rsch dot comm dot mot dot com>
- Cc: libstdc++ at gcc dot gnu dot org, joel dot sherrill at OARcorp dot com
- Date: Mon, 28 Apr 2003 10:21:39 +0200
- Subject: Re: gcc 3.2.3 config/os/bits/i386/atomicity.h broken
- References: <200304251532.h3PFWaUi011532@latour.rsch.comm.mot.com>
Loren James Rittle <rittle at latour dot rsch dot comm dot mot dot com> writes:
> [...]
> However, the patch within implies to me that plain xchgl will fail on
> x86-64 (would a compiler configured as i386-*-* be expected to support
> x86-64? was the patch pessimistic?):
>
> http://www.x86-64.org/lists/discuss/msg01969.html
>
> (The reason, I'm questioning above, is because I don't know. I recall
> that the 68K weakened the strength of TAS between 000 and 0[12]0 when
> they added support for MP and a new bus locking protocol. But that
> was a lifetime ago.)
xchgl will work correctly on x86-64. The only problem (and that's why
it was disabled temporarily in the patch you mentioned) is that
arguments to it might have a different size.
Andreas
--
Andreas Jaeger
SuSE Labs aj at suse dot de
private aj at arthur dot inka dot de
http://www.suse.de/~aj