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Date: Mon, 08 Oct 2012 12:25:04 +1030
From: Shane Ambler <FreeBSD@ShaneWare.Biz>
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To: Tijl Coosemans <tijl@coosemans.org>
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Cc: gerald@freebsd.org, FreeBSD-ports <freebsd-ports@freebsd.org>
Subject: Re: Possible regression in i386 build with gcc 4.6
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On 08/10/2012 08:40, Tijl Coosemans wrote:

>> inline long long
>> atomic_exchange_and_add (volatile long long *at, long long x)
>> {
>> #ifdef USE_GCC_ATOMICS
>>      return __sync_fetch_and_add (at, x);
>> #elif USE_TBB
>>      atomic<long long> *a = (atomic<long long> *)at;
>
> This cast is dangerous. It looks like atomic<long long> has 8 byte
> alignment, but long long on i386 only has 4 byte alignment.
>

Could that be the cause of the seg fault?

gcc42 just happens to generate it into a place that equals 8 byte align 
where gcc46 doesn't?